Temporal effects of ruminal propionic acid infusion on feeding behavior of Holstein cows in the postpartum period

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Gabriela Maldini, Michael S. Allen
ABSTRACTThe objective of this study was to determine the temporal effects of intraruminal infusion of propionic acid at the initiation of meals on feeding behavior of cows in the postpartum period. Propionic acid derived from ruminal fermentation can reduce energy intake of dairy cows. The suppression of appetite by propionic acid is likely caused by a signal related to the hepatic oxidation of fuels. Greater propionate flux to the liver is expected to result in faster oxidation of acetyl coenzyme A, which can stimulate satiety and reduce feed intake. Therefore, the rate of propionate supply to the liver, within the timeframe of meals, might be an important limitation to feed intake. Our hypothesis was that faster rate of propionate infusion during meals would decrease meal size and feed intake by decreasing the time required to stimulate satiety within a meal. Six ruminally cannulated, multiparous Holstein cows in the postpartum period were used in a duplicated 3 × 3 Latin square design experiment balanced for carryover effects. Treatments included control (no infusion) or 1.25 mol of propionic acid infused over 5 min (FST) or 15 min (SLW) at each meal. Infusions were initiated at the conditioned meal at feeding (1200 h) and were triggered at each spontaneous meal for 22 h. Contrary to our hypothesis, SLW decreased meal size 29% (0.87 vs. 1.23 kg of dry matter) compared with FST, and FST decreased meal frequency 27% (8.5 vs. 11.2 per d) compared with SLW. Dry matter intake was similar between FST and SLW, but propionic acid decreased dry matter intake 46% compared with control. A potential explanation is that FST resulted in greater liver bypass of propionate compared with SLW, extending anaplerosis of the tricarboxylic acid cycle, hepatic oxidation of acetyl coenzyme A, and satiety over a longer time after meals.



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Effect of milk cessation method at dry-off on behavioral activity of dairy cows

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): P.J. Rajala-Schultz, P.N. Gott, K.L. Proudfoot, G.M. Schuenemann
ABSTRACTDrying cows off at the end of lactation is a routine management practice in dairy operations. Most dairies in the United States and many other countries dry cows off abruptly (e.g., stop milking cows on a set day), which has been shown to affect cow comfort. Gradually reducing milk production is another approach to dry cows off, routinely used in some countries and herds. The objective of the study was to evaluate the effects of abrupt and gradual milk cessation and milk yield at the time on cow activity after dry-off. Daily lying time, number of lying bouts per day, average lying bout length, and steps taken per day by abruptly and gradually dried-off cows were monitored by data loggers for 2 wk before and after the final milking at the end of lactation. Gradual cows were milked once daily for the last week of lactation, and abrupt cows were milked as usual (3×/d) until the end of lactation. Gradual cessation of milking significantly reduced milk yield by the day of dry-off. After dry-off, gradual cows tended to have longer lying bouts than abrupt cows, but no other differences in cow activity between the 2 treatments were observed. Regardless of the dry-off method, the average length of a lying bout decreased by 4 min and total daily lying time decreased by 19 min after dry-off for each 5-kg increase in milk yield before dry-off. Lying behavior of primiparous cows was more affected by the level of milk yield at dry-off than that of older cows. A reduction in lying times with increasing milk yield may indicate discomfort due to the accumulating milk in the udder. Using a method that lowers milk production before dry-off and managing primiparous and multiparous cows separately around dry-off are beneficial for cow comfort after dry-off.



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News and Announcements

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4





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Phenotypic and genetic relationships between indicators of the mammary gland health status and milk composition, coagulation, and curd firming in dairy sheep

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Michele Pazzola, Claudio Cipolat-Gotet, Giovanni Bittante, Alessio Cecchinato, Maria L. Dettori, Giuseppe M. Vacca
ABSTRACTThe present study investigated the effect of somatic cell count, lactose, and pH on sheep milk composition, coagulation properties (MCP), and curd firming (CF) parameters. Individual milk samples were collected from 1,114 Sarda ewes reared in 23 farms. Milk composition, somatic cell count, single point MCP (rennet coagulation time, RCT; curd firming time, k20; and curd firmness, a30, a45, and a60), and CF model parameters were achieved. Phenotypic traits were statistically analyzed using a mixed model to estimate the effects of the different levels of milk somatic cell score (SCS), lactose, and pH, respectively. Additive genetic, herd, and residual correlations among these 3 traits, and with milk composition, MCP and CF parameters, were inferred using a Bayesian approach. From a phenotypic point of view, higher SCS levels caused a delayed gelification of milk. Lactose concentration and pH were significant for many milk quality traits, with a very intense effect on both coagulation times and curd firming. These traits (RCT, RCT estimated using the curd firming over time equation, and k20) showed an unfavorable increase of about 20% from the highest to the lowest level of lactose. Milk samples with pH values lower than 6.56 versus higher than 6.78 were characterized by an increase of RCT (from 6.00 to 14.3 min) and k20 (from 1.65 to 2.65 min) and a decrease of all the 3 curd firmness traits. From a genetic point of view, the marginal posterior distribution of heritability estimates evidenced a large and exploitable variability for all 3 phenotypes. The mean intra-farm heritability estimates were 0.173 for SCS, 0.418 for lactose content, and 0.206 for pH. Lactose (favorably), and SCS and pH (unfavorably), at phenotypic and genetic levels, were correlated mainly with RCT and RCT estimated using the curd firming over time equation and scarcely with the other curd firming traits. The SCS, lactose, and pH were significantly correlated with each other's. In conclusion, results reported in the present study suggest that SCS, pH, and lactose affect, contemporarily and independently, milk quality and MCP. These phenotypes, easily available during milk recording schemes measured by infrared spectra prediction, could be used as potential indicators traits for improving cheese-making ability of ovine milk.



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Effect of dietary fish oil supplements alone or in combination with sunflower and linseed oil on ruminal lipid metabolism and bacterial populations in lactating cows

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): P. Kairenius, H. Leskinen, V. Toivonen, S. Muetzel, S. Ahvenjärvi, A. Vanhatalo, P. Huhtanen, R.J. Wallace, K.J. Shingfield
ABSTRACTFish oil (FO) alters ruminal biohydrogenation causing trans fatty acid (FA) intermediates to accumulate, but the effects of 18-carbon polyunsaturated FA supply on ruminal long-chain FA metabolism and microbial communities in cattle fed FO are not well established. Four cows fitted with rumen cannula were used in a 4 × 4 Latin square with 21-d experimental periods to evaluate the effects of FO alone or in combination with plant oils high in 18:2n-6 or 18:3n-3 on rumen microbial ecology and flow of FA at the omasum. Treatments comprised a basal grass silage-based diet containing no additional oil (control) or supplements of FO (200 g/d) or FO (200 g/d) plus 500 g/d of sunflower oil (SFO) or linseed oil (LFO). Flow of FA was determined using the omasal sampling technique. The relative abundance of key biohydrogenating bacteria was assessed by quantitative PCR on 16S rRNA genes in omasal digesta. Fish oil-supplemented treatments increased the amounts of trans-18:1, trans-18:2, and 20- to 22-carbon polyunsaturated FA escaping the rumen. Relative to the control, oil supplements had no effect on the amount of 18:0 leaving the rumen, but LFO decreased the flow of 18:0 at the omasum compared with SFO. Both SFO and LFO increased trans-18:1 relative to FO, whereas LFO resulted in the highest trans-18:2 and 20- to 22-carbon FA flow. Supplements of FO plus plant oils shifted biohydrogenation toward trans-10 18:1 formation. Compared with FO alone, the ruminal metabolism of 22:6n-3 in the rumen of lactating cows is more extensive on diets containing higher amounts of 18-carbon polyunsaturated FA. However, the biohydrogenation of 22:5n-3 was less extensive in LFO than SFO, but showed no difference between FO and diets containing plant oils. Ruminal outflow of 20:5n-3 was not altered when plant oils were added to FO. Alterations in the amount of intermediates at the omasum or ruminal biohydrogenation pathways were not accompanied by major changes in analyzed bacterial populations. In conclusion, dietary supplements of FO alone or in combination with plant oils increase the amount of biohydrogenation intermediates containing 1 or more trans double bonds escaping the rumen, which may have implications for host metabolism and the nutritional quality of ruminant foods.



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Short communication: Field study to investigate the associations between herd-level risk factors for milk fat depression and bulk tank milk fat percent in dairy herds feeding monensin

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): M.M. McCarthy, T.R. Overton, G.D. Mechor, D.E. Bauman, T.C. Jenkins, D.V. Nydam
ABSTRACTFat is the most variable milk component, and maintaining milk fat continues to be a challenge on commercial dairy farms. Our objectives were to establish associations between herd-level risk factors for milk fat depression and bulk tank milk fat content in commercial dairy herds feeding monensin. Seventy-nine Holstein commercial dairy herds in the northeast and Upper Midwest United States were enrolled in an observational study. Data were collected on herd characteristics, total mixed ration (TMR) samples, all component silage samples, and bulk tank milk samples. The unconditional univariable association of each explanatory variable and bulk tank milk fat percentage was evaluated using simple linear regression and multivariable regression models. Milk fat content of trans-10 C18:1 had an exponentially negative relationship to herd milk fat percentage. In general, milk fat content of fatty acids synthesized de novo in the mammary gland were positively related to herd milk fat, and the content of several trans-C18:1 fatty acids, which would be products of alternate pathways of ruminal biohydrogenation, were negatively related to herd milk fat. Variables related to TMR composition did not have univariable relationships with herd milk fat percentage. Herds that had >49.8% of the TMR particles on the middle screen of the Penn State particle separator had higher milk fat percentage than those with ≤49.8%, and herds with >54.0% of TMR particles in the bottom pan had lower milk fat percentage than herds with ≤54.0%. Dietary content of monounsaturated fatty acids (C16:1 and C18:1) had negative relationships with herd milk fat percentage; however, no single diet component accounted for more than 11% of the variation in herd-level milk fat percentage. Univariable monensin dose was not associated with herd milk fat percentage. The relative lack of significant univariate relationships with herd-level milk fat suggests many factors contribute to milk fat content, and herds experiencing low milk fat will need to examine many potential risk factors when working to troubleshoot this challenge.



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Randomized double-blind controlled clinical trial of the blood pressure–lowering effect of fermented milk with Lactococcus lactis: A pilot study12

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Lilia M. Beltrán-Barrientos, Aarón F. González-Córdova, Adrián Hernández-Mendoza, Eduardo H. Torres-Inguanzo, Humberto Astiazarán-García, Julián Esparza-Romero, Belinda Vallejo-Cordoba
ABSTRACTThe blood pressure–lowering effect of fermented milk with Lactococcus lactis NRRL B-50571 was evaluated in a double-blind randomized controlled clinical trial with prehypertensive subjects. Participants were randomized into 2 groups (n = 18 each group): one group treated with fermented milk with Lactococcus lactis NRRL B-50571 and a control group treated with artificially acidified milk. Results revealed that during daily consumption of fermented milk for 5 wk, systolic [(116.55 ± 12.26 mmHg vs. 124.77 ± 11.04 mmHg) and diastolic blood pressure (80.7 ± 9 vs. 84.5 ± 8.5 mmHg)] from the fermented milk group was lower than the control group. Additionally, triglyceride, total cholesterol, and low-density lipoprotein in blood serum were lower in the fermented milk group than in the control group. Results demonstrated that daily consumption of fermented milk with Lactococcus lactis (NRRL B-50571) had a blood pressure–lowering effect on prehypertensive subjects. Regular consumption of this product may be used as a potential functional food.



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Peptidomic screening of bitter and nonbitter casein hydrolysate fractions for insulinogenic peptides

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Niamh M. Murray, Dolores O'Riordan, Jean-Christophe Jacquier, Michael O'Sullivan, Thérèse A. Holton, Kieran Wynne, Randall C. Robinson, Daniela Barile, Søren D. Nielsen, David C. Dallas
ABSTRACTSodium caseinate hydrolysates (NaCaH) contain biologically active peptides that can positively influence human health. However, their intense bitterness hinders their inclusion in food products. To our knowledge, no studies have investigated whether a correlation between bitterness and bioactivity exists in NaCaH, so it is not yet known what effect selective removal of bitterness has on NaCaH bioactivity. A deeper understanding of the physicochemical characteristics affecting both bitterness and bioactivity is therefore needed. The aim of this study was to use in silico analysis to elucidate the relationship between bitterness and bioactivity of the insulinogenic NaCaH. The NaCaH fractions were generated by membrane filtration and flash chromatography and were subsequently evaluated for bitterness by a sensory panel. In this present study, peptidomic and bioinformatic processing of these NaCaH fractions allowed for the identification of insulinogenic peptides as well as other literature-identified peptides in each of the fractions. The results showed that the most bitter fraction contained the highest abundance of insulinogenic peptides, whereas another bitter fraction contained the highest abundance of other literature-identified bioactive peptides exhibiting angiotensin-converting enzyme–inhibition activity. Although some bioactive peptides were identified in the least bitter fractions, the abundance of these peptides was very low. These observations show a correlation between bitter taste and bioactivity, highlighting potential complications in removing bitterness while maintaining bioactivity. However, as the most bitter fraction contained the highest abundance of insulinogenic peptides, there is potential for using a lower dose of this enriched bioactive fraction to exert health benefits. The second most bitter fraction contained a very low abundance of insulinogenic peptides and other bioactive peptides. Therefore, removal of this fraction could reduce the NaCaH product's bitterness without significantly altering overall bioactive potential.



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Interpretive Summaries, April 2018

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4





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Long-term palmitic acid supplementation interacts with parity in lactating dairy cows: Production responses, nutrient digestibility, and energy partitioning

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): J. de Souza, A.L. Lock
ABSTRACTThe objective of our study was to evaluate the effects of long-term palmitic acid (C16:0) supplementation and parity on production, nutrient digestibility, and energy partitioning of mid-lactation dairy cows. Forty mid-lactation Holstein cows (18 primiparous and 22 multiparous) were used in a block design. Cows were assigned to receive either a control diet containing no supplemental fat (CON) or a C16:0-enriched supplemented diet (PA; 1.5% diet dry matter) fed for 10 wk. Compared with CON, PA increased dry matter intake, milk yield, cumulative milk yield, milk fat content, milk fat yield, 16-carbon milk fatty acid (FA) yield, 3.5% fat-corrected milk yield, and energy-corrected milk yield. Additionally, PA increased body weight change, but did not affect body condition score change compared with CON. A tendency for a treatment by parity interaction was observed for milk yield due to PA increasing milk yield in multiparous but not in primiparous cows. In addition, we observed interactions between treatment and parity for fat-corrected milk, energy-corrected milk, and milk fat yield due to PA increasing these variables to a greater extent in multiparous compared with primiparous cows. Interestingly, we observed an interaction between treatment and parity for body weight change, due to PA increasing body weight change in primiparous but not in multiparous cows. The PA treatment increased dry matter and neutral detergent fiber digestibilities compared with CON. Although PA did not affect 18-carbon FA digestibility, compared with CON, PA decreased 16-carbon and total FA digestibilities and increased total FA intake by 470 g/d and absorbed total FA by 316 g/d. We also observed an interaction between treatment and parity for total absorbed FA due to PA increasing it to a greater extent in multiparous than in primiparous cows. Compared with CON, PA increased apparent energy intake and milk energy output. We observed an interaction between treatment and parity for milk energy output due to PA increasing milk energy output to a greater extent in multiparous than primiparous cows. Additionally, an interaction between treatment and parity was observed for energy output in body reserves due to PA increasing energy output in body reserves in primiparous but not in multiparous cows. In conclusion, production responses of dairy cows to PA were consistent throughout the 10-wk treatment period. In addition, PA supplementation interacted with parity, with production responses increased to a greater extent in multiparous than primiparous cows and energy partitioned to body reserves only increased in primiparous cows.



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Characterization and milk coagulating properties of Cynanchum otophyllum Schneid. proteases

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Jie Luo, Chen Xiao, Hao Zhang, Fazheng Ren, Xingen Lei, Zibiao Yang, Zhengquan Yu
ABSTRACTThe herbaceous plant Cynanchum otophyllum Schneid. is widely used as a milk coagulant to make a Chinese traditional milk product, milk cake. However, the milk-clotting compounds and their mechanism remain unclear. In this study, crude proteases were extracted from the dried leaves of Cynanchum otophyllum Schneid. using citric acid-phosphate buffer and then partially purified by weak anion exchange chromatography. Two proteases, QA and QC, with molecular weights of 14 and 27 kDa, respectively, were shown to exhibit milk-clotting activity. A study of the effects of pH and temperature on the milk-clotting activity and proteolytic activity of the proteases showed that they exhibited good pH stability from pH 5.5 to 7.5 and good thermal stability at temperatures from 50 to 70°C. The QA and QC were the cysteine proteases, able to hydrolyze β-casein and κ-casein completely, and α-casein partially. The cleavage site on κ-casein determined by Orbitrap (Thermo Fisher Scientific, San Jose, CA) analysis showed that QA and QC could cleave κ-casein at Ser132-Thr133. Overall, the results suggest that the Cynanchum otophyllum Schneid. proteases are a promising milk-clotting enzyme that could be used for manufacturing milk cake and cheese.



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Effect of milk protein composition of a model infant formula on the physicochemical properties of in vivo gastric digestates

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): N. Rafiee Tari, M.Z. Fan, T. Archbold, E. Kristo, A. Guri, E. Arranz, M. Corredig
ABSTRACTWe investigated the effect of protein composition and, in particular, the presence of whey proteins or β-casein on the digestion behavior of a model infant formula using an in vivo piglet model. Three isocaloric diets optimized for piglets were prepared with the same concentrations of protein. For protein source, 1 diet contained only whey proteins and 2 contained a casein:whey protein ratio of 40:60 but differed in the amount of β-casein. To obtain the desired protein compositions, skim milk was microfiltered at 7 or 22°C, and retentates and permeates were combined with whey protein isolate. The diets were optimized to the nutritional needs of the piglets and fed to 24 newborn piglets for 18 d. Eight piglets were also fed ad libitum with sow milk and considered only as reference (not included in the statistical analysis). The study was carried out in 2 blocks, killing the animals 60 and 120 min after the last meal. All gastric contents, regardless of diet, showed a wide range of pH. Postprandial time did not affect the pH or physical properties of the gastric digesta. The digesta from whey protein-casein formulas showed significantly higher viscosity, a higher storage modulus, and a denser microstructure than digesta obtained from piglets fed whey protein formula. The β-casein:total casein ratio at the level used in this study did not significantly affect the physical and chemical properties of the stomach digestate. Although caseins showed extensive gastric hydrolysis, whey proteins remained largely intact at both postprandial times. The results indicate that the presence of different concentrations of milk proteins can be critical to the digestion properties of the food matrix and may affect the nutritional properties of the components.



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Genome-wide association analyses based on a multiple-trait approach for modeling feed efficiency

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Y. Lu, M.J. Vandehaar, D.M. Spurlock, K.A. Weigel, L.E. Armentano, E.E. Connor, M. Coffey, R.F. Veerkamp, Y. de Haas, C.R. Staples, Z. Wang, M.D. Hanigan, R.J. Tempelman
ABSTRACTGenome-wide association (GWA) of feed efficiency (FE) could help target important genomic regions influencing FE. Data provided by an international dairy FE research consortium consisted of phenotypic records on dry matter intakes (DMI), milk energy (MILKE), and metabolic body weight (MBW) on 6,937 cows from 16 stations in 4 counties. Of these cows, 4,916 had genotypes on 57,347 single nucleotide polymorphism (SNP) markers. We compared a GWA analysis based on the more classical residual feed intake (RFI) model with one based on a previously proposed multiple trait (MT) approach for modeling FE using an alternative measure (DMI|MILKE,MBW). Both models were based on a single-step genomic BLUP procedure that allowed the use of phenotypes from both genotyped and nongenotyped cows. Estimated effects for single SNP markers were small and not statistically important but virtually identical for either FE measure (RFI vs. DMI|MILKE,MBW). However, upon further refining this analysis to develop joint tests within nonoverlapping 1-Mb windows, significant associations were detected between either measure of FE with a window on each of Bos taurus autosomes BTA12 and BTA26. There was, as expected, no overlap between detected genomic regions for DMI|MILKE,MBW and genomic regions influencing the energy sink traits (i.e., MILKE and MBW) because of orthogonal relationships clearly defined between the various traits. Conversely, GWA inferences on DMI can be demonstrated to be partly driven by genetic associations between DMI with these same energy sink traits, thereby having clear implications when comparing GWA studies on DMI to GWA studies on FE-like measures such as RFI.



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Short communication: Development of a rapid laboratory method to polymerize lactose to nondigestible carbohydrates

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): A.F. Kuechel, T.C. Schoenfuss
ABSTRACTNondigestible carbohydrates with a degree of polymerization between 3 and 10 (oligosaccharides) are commonly used as dietary fiber ingredients in the food industry, once they have been confirmed to have positive effects on human health by regulatory authorities. These carbohydrates are produced through chemical or enzymatic synthesis. Polylactose, a polymerization product of lactose and glucose, has been produced by reactive extrusion using a twin-screw extruder, with citric acid as the catalyst. Trials using powdered cheese whey permeate as the lactose source for this reaction were unsuccessful. The development of a laboratory method was necessary to investigate the effect of ingredients present in permeate powder that could be inhibiting polymerization. A Mars 6 Microwave Digestion System (CEM Corp., Matthews, NC) was used to heat and polymerize the sugars. The temperatures had to be lowered from extrusion conditions to produce a caramel-like product and not decompose the sugars. Small amounts of water had to be added to the reaction vessels to allow consistent heating of sugars between vessels. Elevated levels of water (22.86 and 28.57%, vol/wt) and calcium phosphate (0.928 and 1.856%, wt/wt) reduced the oligosaccharide yield in the laboratory method. Increasing the citric acid (catalyst) concentration increased the oligosaccharide yield for the pure sugar blend and when permeate powder was used. The utility of the laboratory method to predict oligosaccharide yields was confirmed during extrusion trials of permeate when this increased acid catalyst concentration resulted in similar oligosaccharide concentrations.



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Characterization of a cryptic plasmid isolated from Lactobacillus casei CP002616 and construction of shuttle vectors based on its replicon

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Xin Song, He Huang, Zhiqiang Xiong, Yongjun Xia, Guangqiang Wang, Boxing Yin, Lianzhong Ai
ABSTRACTThe cryptic plasmid pLC2W was isolated from Lactobacillus casei CP002616. Nucleotide sequence analysis revealed that 4 putative open reading frames (ORF) were responsible for DNA replication. Four Escherichia coli-Lactobacillus shuttle vectors were constructed using different lengths of the pLC2W replicon to identify the shortest functional replicon. The length of the pLC2W replicon did not affect the stability of the plasmids. Green fluorescent protein (GFP) as a reporter was expressed successfully in several lactobacilli using our constructed vectors. The results suggested that the expression vectors pUE-F0GFP and pUE-F1GFP are potential molecular tools for heterologous gene cloning and expression in lactobacilli. Moreover, 2 plasmid-curing methods were used to eliminate pLC2W from L. casei. We detected no difference between L. casei CP002616 and L. casei CP002616 pLC2WΔ-IC (mutant strain cured by plasmid incompatibility method) in production of exopolysaccharide (EPS) or acid. However, EPS and acid production were both reduced in L. casei CP002616 pLC2WΔ-HT (mutant strain cured by high-temperature heat treatment method), demonstrating a difference between these 2 curing methods. Sequence analysis of pLC2W and plasmid curing data suggest that plasmid pLC2W is not involved in EPS synthesis.



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Differential effects of a single dose of oral calcium based on postpartum plasma calcium concentration in Holstein cows

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): B.M. Leno, R.C. Neves, I.M. Louge, M.D. Curler, M.J. Thomas, T.R. Overton, J.A.A. McArt
ABSTRACTOur objectives were to determine (1) the effect of a single dose of an oral Ca bolus within 24 h after parturition on plasma Ca concentration, (2) the response of primiparous (PP) and multiparous (MP) cows to this supplementation strategy, and (3) differential responses based on plasma Ca at enrollment. For objective 1, cows from 1 commercial dairy in New York State were enrolled within 19 h after parturition (mean ± standard deviation = 8.3 ± 5.3 h) and randomized within parity group (first, second, and ≥third) to control [CON (n = 25); no placebo] or a single dose bolus treatment [BOL (n = 25); 3 oral Ca boluses supplying 54 to 64 g of Ca]. Plasma Ca was measured repeatedly between 1 and 24 h following treatment. For objectives 2 and 3, cows on 6 commercial farms in New York State were assigned to treatment as for objective 1 (CON, n = 1,973; BOL, n = 1,976). Herd records for health, reproduction, and Dairy Herd Improvement Association test day milk production were collected. Mixed effect multivariable models were developed using repeated measures ANOVA, Poisson regression, or proportional hazard models. Objective 2 analyses considered treatment with periparturient risk factors, whereas objective 3 analyses also considered Ca status. No difference was observed for plasma Ca between 1 and 24 h after treatment. Primiparous cows assigned to BOL calving at >712 d old had decreased risk of one or more health disorders [≤30 d in milk; risk ratio (RR) = 0.65, 95% confidence interval (CI) = 0.51 to 0.84] and those with body condition score >3.5 responded to BOL with increased milk production (CON = 31.7 ± 1.1, BOL = 35.1 ± 1.1 kg/d), as did those with days carried calf >277 (CON = 31.9 ± 1.0, BOL = 34.7 ± 1.0 kg/d). Reduced risk of one or more health disorders was observed in parity ≥3 (RR = 0.85, 95% CI = 0.81 to 0.89) and MP cows with body condition score >3.5 (retained placenta; RR = 0.70, 95% CI = 0.58 to 0.84) or that were lame (displaced abomasum; RR = 0.49, 95% CI = 0.32 to 0.75). Differential responses for PP cows by Ca status were minimal. For MP cows with low plasma Ca, BOL decreased risk of additional Ca treatment (≤1.8 mmol/L; RR = 0.57, 95% CI = 0.40 to 0.80) as well as risk of one or more health disorders (≤2.15 mmol/L; RR = 0.90, 95% CI = 0.85 to 0.95). Supplementation with a single oral dose of Ca could be targeted to periparturient risk groups for improved health. Calcium status did not differentiate responses of PP cows, but MP cows with low Ca at parturition had improved health status when supplemented.



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Technological characterization of Lactobacillus in semihard artisanal goat cheeses from different Mediterranean areas for potential use as nonstarter lactic acid bacteria

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Zhaoxu Meng, Lanwei Zhang, Liang Xin, Kai Lin, HuaXi Yi, Xue Han
ABSTRACTThe potential of 25 Lactobacillus isolates from 8 semihard artisanal goat cheeses manufactured in 4 different Mediterranean areas was examined for use as nonstarter lactic acid bacteria. The isolates were identified using 16S rDNA sequence analysis. Sixteen strains belonged to Lactobacillus paracasei and 9 to Lactobacillus rhamnosus. The isolates were first screened for salt tolerance, exopolysaccharide and diacetyl production, proteolytic and lipolytic activity, and acidification and autolyzing capacities. Most of the lactobacilli displayed strong salt tolerance [20 strains, including 13 of Lb. paracasei and 7 of Lb. rhamnosus, could grow at 6% (wt/vol) salt], low acidification activity (16 strains, including 9 of Lb. paracasei and 7 of Lb. rhamnosus, presented change in pH ≤0.4 U after 6 h of growth), and high autolytic activity (14 strains, including 9 of Lb. paracasei and 5 of Lb. rhamnosus, showed autolysis values ranging between 25 and 65%). Eleven Lb. paracasei and 6 Lb. rhamnosus produced exopolysaccharide, whereas 8 Lb. paracasei and 4 Lb. rhamnosus produced diacetyl. Moreover, 9 Lb. paracasei and 6 Lb. rhamnosus showed proteolytic activity; none of the isolates showed lipolytic activity. Based on the above characteristics, 8 strains were further evaluated for peptidase activity, including aminopeptidase, dipeptidyl aminopeptidase, and dipeptidase activities. The results indicated that all strains showed peptidase activity toward selected substrates. The substrate specificity and extent of peptidase activities were strain-dependent. Four strains (A-3, B-4, D-3, and D-8) presented the best characteristics and represented the most promising nonstarter lactic acid bacteria candidates for use in industrial manufacturing of goat cheese.



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Effect of adding clay with or without a Saccharomyces cerevisiae fermentation product on the health and performance of lactating dairy cows challenged with dietary aflatoxin B1

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Y. Jiang, I.M. Ogunade, D.H. Kim, X. Li, A.A. Pech-Cervantes, K.G. Arriola, A.S. Oliveira, J.P. Driver, L.F. Ferraretto, C.R. Staples, D. Vyas, A.T. Adesogan
ABSTRACTThe study was conducted to examine the effect of supplementing bentonite clay with or without a Saccharomyces cerevisiae fermentation product (SCFP; 19 g of NutriTek + 16 g of MetaShield, both from Diamond V, Cedar Rapids, IA) on the performance and health of dairy cows challenged with aflatoxin B1 (AFB1). Twenty-four lactating Holstein cows (64 ± 11 d in milk) were stratified by parity and milk production and randomly assigned to 1 of 4 treatment sequences. The experiment had a balanced 4 × 4 Latin square design with 6 replicate squares, four 33-d periods, and a 5-d washout interval between periods. Cows were fed a total mixed ration containing 36.1% corn silage, 8.3% alfalfa hay, and 55.6% concentrate (dry matter basis). Treatments were (1) control (no additives), (2) toxin (T; 1,725 µg of AFB1/head per day), (3) T + clay (CL; 200 g/head per day; top-dressed), and (4) CL+SCFP (CL+SCFP; 35 g/head per day; top-dressed). Cows were adapted to diets from d 1 to 25 (predosing period) and then orally dosed with AFB1 from d 26 to 30 (dosing period), and AFB1 was withdrawn from d 31 to 33 (withdrawal period). Milk samples were collected twice daily from d 21 to 33, and plasma was sampled on d 25 and 30 before the morning feeding. Transfer of ingested AFB1 into milk aflatoxin M1 (AFM1) was greater in T than in CL or CL+SCFP (1.65 vs. 1.01 and 0.94%, respectively) from d 26 to 30. The CL and CL+SCFP treatments reduced milk AFM1 concentration compared with T (0.45 and 0.40 vs. 0.75 µg/kg, respectively), and, unlike T, both CL and CL+SCFP lowered AFM1 concentrations below the US Food and Drug Administration action level (0.5 µg/kg). Milk yield tended to be greater during the dosing period in cows fed CL+SCFP compared with T (39.7 vs. 37.7 kg/d). Compared with that for T, plasma glutamic oxaloacetic transaminase concentration, indicative of aflatoxicosis and liver damage, was reduced by CL (85.9 vs. 95.2 U/L) and numerically reduced by CL+SCFP (87.9 vs. 95.2 U/L). Dietary CL and CL+SCFP reduced transfer of dietary AFB1 to milk and milk AFM1 concentration. Only CL prevented the increase in glutamic oxaloacetic transaminase concentration, and only CL+SCFP prevented the decrease in milk yield caused by AFB1 ingestion.



https://ift.tt/2GOwpa4

Effects of feeding hulled and hull-less barley with low- and high-forage diets on lactation performance, nutrient digestibility, and milk fatty acid composition of lactating dairy cows

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): Y. Yang, G. Ferreira, C.L. Teets, B.A. Corl, W.E. Thomason, C.A. Griffey
ABSTRACTThe objective of this study was to evaluate lactation performance, nutrient digestibility, and milk fatty acid composition of high-producing dairy cows consuming diets containing hulled or hull-less barley as the grain source when feeding low-forage (LF) or high-forage (HF) diets. Eight primiparous (610 ± 40 kg of body weight and 72 ± 14 d in milk) and 16 multiparous (650 ± 58 kg of body weight and 58 ± 16 d in milk) Holstein cows were randomly assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments and 21-d periods. Cows were assigned to squares based on parity (1, 2, and ≥3) and days in milk. Diets were formulated to contain on a dry matter basis (1) 45% forage and hulled barley as the sole grain source, (2) 65% forage and hulled barley as the sole grain source, (3) 45% forage and hull-less barley as the sole grain source, and (4) 65% forage and hull-less barley as the sole grain source. Dry matter intake tended to be lower for the diet with 65% forage and hulled barley than for the rest of the diets (24.4 vs. 26.6 kg/d). Neither the type of barley nor the forage-to-concentrate ratio affected milk yield (41.7 kg/d). Barley type did not affect milk fat or protein concentrations. Feeding LF diets decreased milk fat concentration from 3.91% to 3.50%. This decrease was less than anticipated and resulted in a 7% decrease in milk fat yield relative to cows consuming HF diets (1.60 and 1.49 kg/d for HF and LF diets, respectively). Feeding LF diets increased the concentration of C18:1 trans-10 in milk fat, suggesting that feeding LF diets may have marginally altered rumen function. In conclusion, LF diets containing barley grains can marginally decrease milk fat concentration. Overall, and based on the conditions of this study, there is limited evidence to anticipate a dramatic or acute milk fat depression when feeding hull-less barley as the grain source in diets for high-producing dairy cows.



https://ift.tt/2Ip7fvZ

Bacterial and fungal communities, fermentation, and aerobic stability of conventional hybrids and brown midrib hybrids ensiled at low moisture with or without a homo- and heterofermentative inoculant

Publication date: April 2018
Source:Journal of Dairy Science, Volume 101, Issue 4
Author(s): J.J. Romero, Y. Joo, J. Park, F. Tiezzi, E. Gutierrez-Rodriguez, M.S. Castillo
ABSTRACTWe evaluated the effects of adding a combination inoculant to 4 corn (Zea mays L.) hybrids harvested at low moisture on the nutritive value, fermentation profile, aerobic stability, bacterial and fungal populations, and community structure. The treatment design was the factorial combination of 4 corn hybrids ensiled with (INO) and without (CON) inoculant. The hybrids were TMF2R737 (MCN), F2F817 (MBR), P2089YHR (PCN), and PI144XR (PBR), ensiled at 44.0, 38.1, 42.0, and 41.3% of dry matter, respectively; MBR and PBR were brown midrib mutants. The inoculant contained Lactobacillus buchneri and Pediococcus pentosaceus (4 × 10⁵ and 1 × 10⁵ cfu/g of fresh corn). The experimental design was a complete randomized design with treatments replicated 6 times. Corn was chopped, treated or not with inoculant, packed into 7.6-L bucket silos, and stored for 100 d. At d 0, we found higher bacterial observed operational taxonomic units in the brown midrib mutants (MBR and PBR) relative to MCN and PCN (654 and 534 vs. 434 and 444 ± 15.5, respectively). The bacterial and fungal families with the highest relative abundance (RA) were Enterobacteriaceae (61.4%) and incertae sedis Tremellales (12.5%). At silo opening, we observed no effects of INO treatment on dry matter recovery (∼94.3 ± 1.07%), but aerobic stability was extended for all INO-treated hybrids (∼217 vs. ∼34.7 h), except for MBR (∼49 ± 38 h), due to a decreased yeast population (3.78 vs. 5.13 ± 0.440 log cfu/g of fresh corn) and increased acetic acid concentration (1.69 vs. 0.51 ± 0.132%) compared with the control. Furthermore, INO treatment reduced bacterial (61.2 vs. 276 ± 8.70) and increased fungal (59.8 vs. 43.6 ± 2.95) observed operational taxonomic units compared with CON. We observed that INO treatment increased the RA of Lactobacillaceae across all hybrids (∼99.1 vs. ∼58.9), and to larger extent MBR (98.3 vs. 34.3 ± 5.29), and decreased Enterobacteriaceae (0.614 vs. 23.5 ± 2.825%) among 4 other bacterial families relative to CON. For fungi, INO treatment increased the RA of Debaryomycetaceae (63.1 vs. 17.3 ± 8.55) and 5 other fungal families and decreased the RA of Pichiaceae (6.47 vs. 47.3 ± 10.95) and incertae sedis Saccharomycetales (8.47 vs. 25.9 ± 5.748) compared with CON. The bacterial and fungal community structures changed, due to ensiling, to a distinct and more stable community dominated by Lactobacillaceae and Debaryomycetaceae, respectively, when INO treatment was applied relative to CON. In conclusion, the INO treatment used in this study improved low-moisture whole-crop corn silage quality because of a shift in the bacterial and fungal community composition during ensiling.



https://ift.tt/2GOw9rC

Is There Really a Benefit to Net Clinical Benefit in Testing Antithrombotics?.

Author: Steg, Philippe Gabriel MD; Bhatt, Deepak L. MD, MPH

Page: 1429-1431

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Reduced Mortality With Sodium-Glucose Cotransporter-2 Inhibitors in Observational Studies: Avoiding Immortal Time Bias.

Author: Suissa, Samy PhD

Page: 1432-1434

https://ift.tt/2IqxIsX

Association of Statin Dose With Amputation and Survival in Patients With Peripheral Artery Disease.

Author: Arya, Shipra MD, SM; Khakharia, Anjali MD, MS; Binney, Zachary O. MPH; DeMartino, Randall R. MD, MS; Brewster, Luke P. MD, PhD; Goodney, Philip P. MD, MS; Wilson, Peter W.F. MD

Page: 1435-1446

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Statins in Peripheral Artery Disease: What Are We Waiting For?.

Author: Aday, Aaron W. MD; Everett, Brendan M. MD, MPH

Page: 1447-1449

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Cardiovascular Outcomes and Risks After Initiation of a Sodium Glucose Cotransporter 2 Inhibitor: Results From the EASEL Population-Based Cohort Study (Evidence for Cardiovascular Outcomes With Sodium Glucose Cotransporter 2 Inhibitors in the Real World).

Author: Udell, Jacob A. MD, MPH; Yuan, Zhong MD, PhD; Rush, Toni MPH; Sicignano, Nicholas M. MPH; Galitz, Michael MD; Rosenthal, Norman MD

Page: 1450-1459

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Sodium Glucose Cotransporter 2 Inhibitors and Amputation Risk: Achilles' Heel or Opportunity for Discovery?.

Author: Bonaca, Marc P. MD, MPH; Beckman, Joshua A. MD, MS

Page: 1460-1462

https://ift.tt/2EfG307

Effect of Losartan on Right Ventricular Dysfunction: Results From the Double-Blind, Randomized REDEFINE Trial (Right Ventricular Dysfunction in Tetralogy of Fallot: Inhibition of the Renin-Angiotensin-Aldosterone System) in Adults With Repaired Tetralogy of Fallot.

Author: Bokma, Jouke P. MD; Winter, Michiel M. MD, PhD; van Dijk, Arie P. MD, PhD; Vliegen, Hubert W. MD, PhD; van Melle, Joost P. MD, PhD; Meijboom, Folkert J. MD, PhD; Post, Martijn C. MD, PhD; Berbee, Jacqueline K. MSc; Boekholdt, S. Matthijs MD, PhD; Groenink, Maarten MD, PhD; Zwinderman, Aeilko H. PhD; Mulder, Barbara J.M. MD, PhD; Bouma, Berto J. MD, PhD

Page: 1463-1471

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Renin-Angiotensin-Aldosterone System Inhibitors for Right Ventricular Dysfunction in Tetralogy of Fallot: Quo Vadis?.

Author: Reddy, Sushma MD; Bernstein, Daniel MD; Newburger, Jane W. MD, MPH

Page: 1472-1474

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Angiography Versus Hemodynamics to Predict the Natural History of Coronary Stenoses: Fractional Flow Reserve Versus Angiography in Multivessel Evaluation 2 Substudy.

Author: Ciccarelli, Giovanni MD; Barbato, Emanuele MD, PhD; Toth, Gabor G. MD, PhD; Gahl, Brigitta MSc; Xaplanteris, Panagiotis MD, PhD; Fournier, Stephane MD; Milkas, Anastasios MD; Bartunek, Jozef MD, PhD; Vanderheyden, Marc MD, PhD; Pijls, Nico MD, PhD; Tonino, Pim MD, PhD; Fearon, William F. MD; Juni, Peter MD; De Bruyne, Bernard MD, PhD

Page: 1475-1485

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Targeting Transmembrane BAX Inhibitor Motif Containing 1 Alleviates Pathological Cardiac Hypertrophy.

Author: Deng, Ke-Qiong MD *,,,,; Zhao, Guang-Nian PhD *,,,,; Wang, Zhihua PhD *,,,,; Fang, Jing MD; Jiang, Zhou PhD; Gong, Jun PhD; Yan, Feng-Juan PhD; Zhu, Xue-Yong BS; Zhang, Peng PhD; She, Zhi-Gang MD, PhD; Li, Hongliang MD, PhD

Page: 1486-1504

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Ultrasound for Lower Extremity Deep Venous Thrombosis: Multidisciplinary Recommendations From the Society of Radiologists in Ultrasound Consensus Conference.

Author: Needleman, Laurence MD; Cronan, John J. MD; Lilly, Michael P. MD; Merli, Geno J. MD; Adhikari, Srikar MD; Hertzberg, Barbara S. MD; DeJong, M. Robert RDMS, RVT; Streiff, Michael B. MD; Meissner, Mark H. MD

Page: 1505-1515

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Pollution Exposure Counteracts Exercise Benefits: Exercise in Green Spaces, Pollution Reductions Recommended.

Author: Kuehn, Bridget M.

Page: 1516-1517

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Highlights From the Circulation Family of Journals.

Author:

Page: 1518-1523

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Mobile Phone Detection of Atrial Fibrillation With Mechanocardiography: The MODE-AF Study (Mobile Phone Detection of Atrial Fibrillation).

Author: Jaakkola, Jussi MD *,; Jaakkola, Samuli MD *,; Lahdenoja, Olli DSc; Hurnanen, Tero MSc; Koivisto, Tero MSc; Pankaala, Mikko DSc; Knuutila, Timo PhD; Kiviniemi, Tuomas O. MD, PhD; Vasankari, Tuija RN; Airaksinen, K.E. Juhani MD, PhD

Page: 1524-1527

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Letter by Spartalis et al Regarding Article, "Modifiable Risk Factors and Atrial Fibrillation".

Author: Spartalis, Michael MD, MSc, PhD; Tzatzaki, Eleni MD, PhD; Spartalis, Eleftherios MD, MSc, PhD

Page: 1528-1529

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Letter by Zei Regarding Article, "Modifiable Risk Factors and Atrial Fibrillation".

Author: Zei, Paul C. MD, PhD

Page: 1530-1531

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Letter by Borghi and Cicero Regarding Article, "Modifiable Risk Factors and Atrial Fibrillation".

Author: Borghi, Claudio MD; Cicero, Arrigo F.G. MD

Page: 1532-1533

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Response by Lau et al to Letters Regarding Article, "Modifiable Risk Factors and Atrial Fibrillation".

Author: Lau, Dennis H. MBBS, PhD; Nattel, Stanley MD, PhD; Kalman, Jonathan M. MBBS, PhD; Sanders, Prashanthan MBBS, PhD

Page: 1534-1535

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Letter by Graudal and Mente Regarding Article, "Use of a Single Baseline Versus Multiyear 24-Hour Urine Collection for Estimation of Long-Term Sodium Intake and Associated Cardiovascular and Renal Risk".

Author: Graudal, Niels MD, DMSc; Mente, Andrew PhD

Page: 1536-1537

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Response by Olde Engberink et al to Letter Regarding Article, "Use of a Single Baseline Versus Multiyear 24-Hour Urine Collection for Estimation of Long-Term Sodium Intake and Associated Cardiovascular and Renal Risk".

Author: Olde Engberink, Rik H.G. MD, PhD; van den Born, Bert-Jan H. MD, PhD; Peters-Sengers, Hessel MSc; Vogt, Liffert MD, PhD

Page: 1538-1539

https://ift.tt/2Ee2KSD

Long-term trends in Swiss rivers sampled continuously over 39 years reflect changes in geochemical processes and pollution

Abstract

Long-term changes of 14 water constituents measured in continuously and water discharge proportionally collected samples of four Swiss rivers over a period of 39 years are analyzed using several statistical techniques. Possible drivers and causes for the identified trends and shifts are explained by consideration of catchment characteristics and anthropogenic activities. Water temperatures increased by 0.8–1.3 °C, whereas water discharges remained largely unchanged. Concentrations of alkalinity, total hardness, Ca, and Mg regulated by dominant carbonate lithologies in catchments increased by up to 10%. We attribute this change to an increase in the partial pressure of CO₂ in the subsurface, provoked by increasing temperatures. Re-oligotrophication processes in lakes also influence the behavior of alkalinity and silicic acid. In contrast to concentrations, most loads did not change significantly, due to their large variances. Therefore, no changes in overall weathering rates of carbonate rocks can be detected. The outgassing of CO₂ in rivers from the place of carbonate dissolution to measurement stations amounts up to 6% (mean) of CO₂ sequestered (mean 1.1 mol m⁻² a⁻¹) by the weathering of rock minerals. Changes in alkalinity/Ca/Mg ratios indicate an increase in calcite precipitation over time. Total nitrogen concentrations and loads peaked at the end of the 1980s and then decreased up to 50%, while NO₃ concentrations showed almost no changes. This dynamic matches the changes in the agricultural N balance. Concentrations and loads of Na and Cl increased up to 60% due to an increase in the various uses of rock salt.

https://ift.tt/2EeXEW7

Application of wavelet analysis to detect dysfunction in cerebral blood flow autoregulation during experimental hyperhomocysteinaemia

Abstract

The purpose of the present study was to investigate the use of laser Doppler flowmetry (LDF) signals coupled with spectral wavelet analysis to detect endothelial link dysfunction in the autoregulation of cerebral blood flow in the setting of hyperhomocysteinaemia (HHcy). Fifty-one rats were assigned to three groups (intact, control, and HHcy) according to the results of biochemical assays of homocysteine level in blood plasma. LDF signals on the rat brain were recorded by LAKK-02 device to measure the microcirculatory blood flow. The laser operating wavelength and output power density were1064 nm and 0.051 W/mm², respectively. A Morlet mother wavelet transform was applied to the measured 8-min LDF signals, and periodic oscillations with five frequency intervals were identified (0.01–0.04 Hz, 0.04–0.15 Hz, 0.15–0.4 Hz, 0.4–2 Hz, and 2–5 Hz) corresponding to endothelial, neurogenic, myogenic, respiratory, and cardiac origins, respectively. In initial state, the amplitude of the oscillations decreased by 38% (P < 0.05) in the endothelial range in HHcy rats than in control rats. Cerebral autoregulation was challenged by hemorrhagic hypotension. The lower limit of autoregulation raised in a rat model of chronic HHcy (71.5 ± 0.7 mmHg in HHcy vs. 62.3 ± 0.5 mmHg in control). The data obtained indicate that the laser Doppler method and wavelet analysis may be successfully applied to detect the dysfunction of the endothelial link in cerebral vessel tone and to reveal the pathological shift of lower limit of autoregulation.

https://ift.tt/2uKbujX

Atmospheric and geogenic CO2 within the crown and root of spruce (Picea abies L. Karst.) growing in a mofette area

Publication date: June 2018
Source:Atmospheric Environment, Volume 182
Author(s): D. Vodnik, A. Thomalla, M. Ferlan, T. Levanič, K. Eler, N. Ogrinc, C. Wittmann, H. Pfanz
Mofettes are often investigated in ecology, either as extreme sites, natural analogues to future conditions under climate change, or model ecosystems for environmental impact assessments of carbon capture and storage systems. Much of this research, however, inadequately addresses the complexity of the gas environment at these sites, mainly focusing on aboveground CO2-enrichment. In the current research, the gaseous environment of Norway spruce (Picea abies (L) Karst.) trees growing at the Stavešinske slepice mofette (NE Slovenia) were studied by measuring both soil ([CO2]soil) and atmospheric CO2 concentrations ([CO2]air). Within the studied site (800 m²), soil CO2 enrichment was spatially heterogeneous; about 25% of the area was characterized by very high [CO2]soil (>40%) and hypoxic conditions. Aboveground gas measurements along vertical profiles not only revealed substantially elevated [CO2]air close to the ground (height up to 1.5 m), but also in the upper heights (20–25 m; crown layer). On the basis δ¹³C of CO2, it was shown that elevated CO2 relates to a geogenic source. Trees grown in high [CO2]soil were characterized by decreased radial growth; the δ¹³C of their wood was less negative than in trees growing in normal soil. Unfavorable gaseous soil conditions should generally be accepted as being by far the most important factor affecting (i.e. disturbing) the growth of mofette trees.



https://ift.tt/2Gy2kZf

Aerosol optical properties and radiative effects: Assessment of urban aerosols in central China using 10-year observations

Publication date: June 2018
Source:Atmospheric Environment, Volume 182
Author(s): Ming Zhang, Yingying Ma, Wei Gong, Boming Liu, Yifan Shi, ZhongYong Chen
Poor air quality episodes are common in central China. Here, based on 10 years of ground-based sun-photometric observations, aerosol optical and radiative forcing characteristics were analyzed in Wuhan, the biggest metropolis in central China. Aerosol optical depth (AOD) in the last decade declined significantly, while the Ångström exponent (AE) showed slight growth. Single scattering albedo (SSA) at 440 nm reached the lowest value (0.87) in winter and highest value (0.93) in summer. Aerosol parameters derived from sun-photometric observations were used as input in a radiative transfer model to calculate aerosol radiative forcing (ARF) on the surface in ultraviolet (UV), visible (VIS), near-infrared (NIR), and shortwave (SW) spectra. ARFSW sustained decreases (the absolute values) over the last 10 years. In terms of seasonal variability, due to the increases in multiple scattering effects and attenuation of the transmitted radiation as AOD increased, ARF in summer displayed the largest value (−73.94 W/m²). After eliminating the influence of aerosol loading, the maximum aerosol radiative forcing efficiency in SW range (ARFESW) achieved a value of −64.5 W/m²/AOD in April. The ARFE change in each sub-interval spectrum was related to the change in SSA and effective radius of fine mode particles (Refff), that is, ARFE increased with the decreases in SSA and Refff. The smallest contribution of ARFENIR to ARFESW was 34.11% under strong absorbing and fine particle conditions, and opposite results were found for the VIS range, whose values were always over 51.82%. Finally, due to the serious air pollution and frequency of haze day, aerosol characteristics in haze and clear days were analyzed. The percentage of ARFENIR increased from 35.71% on clear-air days to 37.63% during haze periods, while both the percentage of ARFEUV and ARFENIR in ARFESW kept decreasing. The results of this paper should help us to better understand the effect of aerosols on solar spectral radiation and to develop improved the aerosol models over central China.



https://ift.tt/2H4ojrE

Colorimetric determination of uranyl (UO22+) in seawater via DNAzyme-modulated photosensitization

Publication date: 1 August 2018
Source:Talanta, Volume 185
Author(s): Chengpeng Huang, Xiaoya Fan, Qiaomei Yuan, Xinfeng Zhang, Xiandeng Hou, Peng Wu
Various DNA-modulated photosensitization schemes have been reported for various applications, but DNAzyme has not yet been included. Here, we found the DNAzyme with metal ion as cofactor could also be efficient in modulation of photosensitization process. The UO22+-specific DNAzyme can switch between double strand DNA (dsDNA) and single strand DNA (ssDNA) upon UO22+ cleavage, which can regulate the photosensitization process of SYBR Green I. Coupling with photosensitization-induced chromogenic reaction (TMB oxidation), a simple colorimetric sensor for UO22+ was developed accordingly. To increase the visual resolution of the proposed assay, a background color was supplied. Compared with the previous DNAzyme-based UO22+ sensors, the proposed assay featured label-free and simple. Besides, the tolerance for high salinity of this assay is appealing. The proposed assay offered a detection limit of 0.08 μg/L with UV−vis detection and 0.5 μg/L with the naked eye. With the proposed colorimetric assay, UO22+ levels in the range of 0.7–1.2 μg/L (2.9–5.0 nM) were identified in high salinity seawater samples, with spike-recoveries ranging from 93% to 104%.

Graphical abstract

https://ift.tt/2uOAxCz

Rapid colorimetric lactoferrin-based sandwich immunoassay on cotton swabs for the detection of foodborne pathogenic bacteria

Publication date: 1 August 2018
Source:Talanta, Volume 185
Author(s): Saleh Alamer, Shimaa Eissa, Raja Chinnappan, Paul Herron, Mohammed Zourob
Cotton swab is the conventional swabbing tool that is usually applied for collecting pathogens from contaminated surfaces, followed by cells lysis and DNA extraction before subjecting to genetic analysis. However, such an approach is time consuming as it involves several steps and requires highly trained personnel to perform the experiment. In this study, we developed a new cotton swab-based detection system that involved integrating bacterial collection, preconcentration and detection on Q-tips. The platform is based on a sandwich assay that can detect different pathogens visually by color changes. Lactoferrin-immobilized cotton is used as a general capturing tool to collect various pathogens from surfaces. The presence of particular bacteria is then detected by immersing the cotton in antibodies attached to different colored nanobeads. The target cell is captured between the lactoferrin and specific antibody-conjugated beads which results in certain color development. The effectiveness of this simply fabricated sensor was demonstrated using Salmonella typhimurium, Salmonella enteritidis, Staphylococcus aureus and Campylobacter jejuni. The intensity of the color on the cotton surfaces increased with increasing the concentration of the pathogenic bacteria. The detection limit was as low as 10 cfu/ml for Salmonella typhimurium and Campylobacter jejuni, 100 cfu/ml for Salmonella enteritidis and 100 cfu/ml for Staphylococcus aureus on chicken meat surface. Moreover, this method showed high selectivity and was further confirmed by loop-mediated isothermal amplification (LAMP). The simplicity and the low cost of this colorimetric sensor renders it applicable to a wide range of other pathogens on different surfaces.

Graphical abstract

https://ift.tt/2pZOOYa

Ratiometric fluorescent detection of chromium(VI) in real samples based on dual emissive carbon dots

Publication date: 1 August 2018
Source:Talanta, Volume 185
Author(s): Yunxia Ma, Yonglei Chen, Juanjuan Liu, Yangxia Han, Sudai Ma, Xingguo Chen
As we know, hexavalent chromium (Cr(VI)) was usually used as an additive to improve the color fastness during the printing and dyeing process, and thus posing tremendous threat to our health and living quality. In this work, the dual emissive carbon dots (DECDs) were synthesized through hydrothermal treatment of m-aminophenol and oxalic acid. The obtained DECDs not only exhibited dual emission fluorescence peaks (430 nm, 510 nm) under the single excitation wavelength of 380 nm, but also possessed good water solubility and excellent fluorescence stability. A ratiometric fluorescent method for the determination of Cr(VI) was developed using the DECDs as a probe. Under the optimal conditions, a linear range was obtained from 2 to 300 μM with a limit of detection of 0.4 μM. Furthermore, the proposed ratiometric fluorescent method was applied to the analysis of Cr(VI) in textile, steel, industrial wastewater and chromium residue samples with satisfactory recoveries (88.4–106.8%).

Graphical abstract

https://ift.tt/2uMANBW

Determination and speciation of ultratrace arsenic and chromium species using aluminium oxide supported on graphene oxide

Publication date: 1 August 2018
Source:Talanta, Volume 185
Author(s): Anna Baranik, Anna Gagor, Ignasi Queralt, Eva Marguí, Rafal Sitko, Beata Zawisza
Alumina supported on graphene oxide (Al2O3/GO) nanocomposite as new nanosorbent in dispersive micro-solid phase extraction (DMSPE) for As(V) and Cr(III) preconcentration is described. The crucial issue of the study is synthesis of novel nanocomposite suitable for sorption of selected species of arsenic and chromium. Al2O3/GO demonstrates selectivity toward arsenates in the presence of arsenites at pH 5 and chromium(III) ions in the presence of chromate anions at pH 6. The Al2O3/GO nanocomposite was characterized by scanning electron microscopy (SEM) transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and the Raman spectroscopy. The maximum adsorption capacity calculated based on the Langmuir adsorption model were 43.9 mg g⁻¹ and 53.9 mg g⁻¹ for As(V) and Cr(III), respectively. The nanocomposite was used as solid sorbent in preconcentration of As(V) and Cr(III)_ions from water samples and their determination using energy dispersive X-ray fluorescence spectrometry (EDXRF). The As(V) and Cr(III) ions can be quantitatively preconcentrated from 25 to 100 mL aqueous samples within 5 min using DMSPE procedure and 1 mg of Al2O3/GO. The nanocomposite was also used for preparation of Al2O3/GO membrane. Then, As(V) and Cr(III)_ions can be retained under flow condition by passing analyzed solution through Al2O3/GO membrane. Under the optimized conditions, As(V) and Cr(III) ions can be determined with very good recovery (92–108%), precision (RSD 2.7–4.0%) and excellent limit of detection (0.02 ng mL⁻¹ As and 0.11 ng mL⁻¹ Cr). The accuracy of the method was studied by analyzing certified reference materials (NIST 1640a) and spiked real water samples.

Graphical abstract

https://ift.tt/2pWiWUf

Distinct and complementary roles of CD4 T cells in protective immunity to influenza virus

Publication date: August 2018
Source:Current Opinion in Immunology, Volume 53
Author(s): Andrea J Sant, Katherine A Richards, Jennifer Nayak
CD4 T cells play a multiplicity of roles in protective immunity to influenza. Included in these functions are help for high affinity antibody production, enhancement of CD8 T cell expansion, function and memory, acceleration of the early innate response to infection and direct cytotoxicity. The influenza-specific CD4 T cell repertoire in humans established through exposures to infection and vaccination has been found to be highly variable in abundance, specificity and functionality. Deficits in particular subsets of CD4 T cells recruited into the response result in diminished antibody responses and protection from infection. Therefore, improved strategies for vaccination should include better methods to identify deficiencies in the circulating CD4 T cell repertoire, and vaccine constructs that increase the representation of CD4 T cells of the correct specificity and functionality.



https://ift.tt/2Ilr6MM

Transcriptional programming of tissue-resident memory CD8+ T cells

Publication date: April 2018
Source:Current Opinion in Immunology, Volume 51
Author(s): J Justin Milner, Ananda W Goldrath
Tissue-resident memory CD8⁺ T cells (TRM) are localized in non-lymphoid tissues throughout the body where they mediate long-lived protective immunity at common sites of pathogen exposure. As the signals controlling TRM differentiation are uncovered, it is becoming apparent that the dynamic activities of numerous transcription factors are intricately involved in TRM formation. Here, we highlight known transcriptional regulators of TRM differentiation and discuss how understanding the transcriptional programming of CD8⁺ T cell residency in non-lymphoid tissues can be leveraged to prevent or treat disease.



https://ift.tt/2GN2GhP

Does the application of silicon and Moringa seed extract reduce heavy metals toxicity in potato tubers treated with phosphate fertilizers?

Abstract

Two field trials were carried out in two successive agricultural seasons to study the possibility of using silicon (Si) and Moringa seed extract (MSE) for reducing heavy metal contamination resulting from phosphate fertilizers addition to potato tubers. A randomized complete block design experiment was performed using three replicates. Various sources of phosphate fertilizers as ordinary super phosphate and rock phosphate were added at rate of 100 kg P ha⁻¹ prior sowing. Silicon was added as potassium silicate (20% SiO₂) at rate of 6 L ha⁻¹, and MSE was also added at rate of 150 L ha⁻¹ in three equal doses with the 2nd, 4th, and 6th irrigations during the last 10 min of drip irrigation. Results indicated that the addition of phosphate fertilizers increased fresh tuber yield, dry weight yield, NPK uptake, catalase, peroxidase, superoxide dismutase, and glutathione reductase of potato either alone or combined with silicon and MSE. The accumulation rate of Cu, Cd, and Ni in potato was higher with the single addition of rock phosphate fertilizer compared with single addition of super phosphate fertilizer. The highest reduction (P < 0.05) in heavy metal accumulation in potato leaves and tubers as well as soil was found with MSE treatment plus super phosphate fertilizer. It is recommended to add MSE at a rate of 150 L ha⁻¹ along with fertilizing the potato crop with ordinary super phosphate fertilizer.

https://ift.tt/2IoqHJs

Identification and quantitation of semi-crystalline microplastics using image analysis and differential scanning calorimetry

Abstract

There are several techniques used to analyze microplastics. These are often based on a combination of visual and spectroscopic techniques. Here we introduce an alternative workflow for identification and mass quantitation through a combination of optical microscopy with image analysis (IA) and differential scanning calorimetry (DSC). We studied four synthetic polymers with environmental concern: low and high density polyethylene (LDPE and HDPE, respectively), polypropylene (PP), and polyethylene terephthalate (PET). Selected experiments were conducted to investigate (i) particle characterization and counting procedures based on image analysis with open-source software, (ii) chemical identification of microplastics based on DSC signal processing, (iii) dependence of particle size on DSC signal, and (iv) quantitation of microplastics mass based on DSC signal. We describe the potential and limitations of these techniques to increase reliability for microplastic analysis. Particle size demonstrated to have particular incidence in the qualitative and quantitative performance of DSC signals. Both, identification (based on characteristic onset temperature) and mass quantitation (based on heat flow) showed to be affected by particle size. As a result, a proper sample treatment which includes sieving of suspended particles is particularly required for this analytical approach.

https://ift.tt/2H7lyWQ

The levels of polycyclic aromatic hydrocarbons (PAHs) in human milk and exposure risk to breastfed infants in petrochemical industrialized Lanzhou Valley, Northwest China

Abstract

We investigated in this paper the presence of PAHs in human milk from lactating women residing in Lanzhou, a petrochemical industrialized valley city in Northwest China. The PAH concentration levels in human milk samples from 98 healthy women were determined by gas chromatography/mass spectrometry (GC/MS). The associations between the lifestyle factors and the PAHs levels of human milk were analyzed. Moreover, we applied principal component analysis (PCA) method to gain a better insight into the similarities or dissimilarities of the human milk PAH loads and different pathways of source exposure. In addition, the exposure risks of breastfed infants due to PAH ingestion via breast milk were assessed and the relative breast-feeding risk to the total intake dose of infants was addressed. The results showed that the average fat-normalized human milk ∑₁₅PAHs concentrations for the lactating women residing in four districts of Lanzhou, namely, Xigu, Anning, Qilihe, and Chengguan were 320.40, 270.36, 374.04, and 259.84 ng/g of fat, respectively. The ∑₁₅PAHs of human milk from the lactating women of Qilihe District exhibited the highest concentration level, while the concentration level for women from Xigu District is the second highest for the observed human milk ∑₁₅PAHs. And the corresponding BaPeq concentrations for women in Xigu, Anning, Qilihe, and Chengguan districts were 58.29, 47.95, 65.13, and 45.60 ng/g of fat, respectively. A significant correlation was only found between human milk and living district environment (p < 0.05). Although the Spearman correlation analysis showed that there were no significant correlation existing between other lifestyle and human milk PAHs, we confirmed that consuming barbecue food could elevate PAHs levels in human milk: the barbecue intake frequency caused 10% fluctuation of ∑₁₅PAHs concentration between high frequency and low frequency group in our study. Furthermore, the exposure to second-hand smoke can also increase the ∑₁₅PAHs levels in human milk by 4 to 11% here. Ingestion doses of PAHs by infants (19.37–77.75 ng kg⁻¹ day⁻¹) were much higher than the inhalation doses (2.83–16.48 ng kg⁻¹ day⁻¹), which indicated that the ingestion is the main exposure risk pathway for infants. Since there are limited guidelines and standards for PAHs ingestion dose in human milk by infant, we compared the ingestion dose of BaP with the upper bound estimates of BaP dietary exposure of 108 ng kg⁻¹ day⁻¹ for toddlers of ages between 1.5 and 2.5 years of age in the UK reported by Committee on Toxicity of Chemicals in Food (COT) and the data we obtained were lower than this upper bound. However, the estimated margin of exposure (MOE) values of BaP-MOE, PAH2-MOE, PAH4-MOE, and PAH8-MOE were smaller than 10,000 which indicated that there are potential hazard for breastfed infants consuming these human milk samples.

https://ift.tt/2Irohd8

Mode of action of nanoparticles against insects

Abstract

The employment of nanoparticles obtained through various synthesis routes as novel pesticides recently attracted high research attention. An impressive number of studies have been conducted to test their toxic potential against a wide number of arthropod pests and vectors, with major emphasis on mosquitoes and ticks. However, precise information on the mechanisms of action of nanoparticles against insects and mites are limited, with the noteworthy exception of silica, alumina, silver, and graphene oxide nanoparticles on insects, while no information is available for mites. Here, I summarize current knowledge about the mechanisms of action of nanoparticles against insects. Both silver and graphene oxide nanoparticles have a significant impact on insect antioxidant and detoxifying enzymes, leading to oxidative stress and cell death. Ag nanoparticles also reduced acetylcholinesterase activity, while polystyrene nanoparticles inhibited CYP450 isoenzymes. Au nanoparticles can act as trypsin inhibitors and disrupt development and reproduction. Metal nanoparticles can bind to S and P in proteins and nucleic acids, respectively, leading to a decrease in membrane permeability, therefore to organelle and enzyme denaturation, followed by cell death. Besides, Ag nanoparticles up- and downregulate key insect genes, reducing protein synthesis and gonadotrophin release, leading to developmental damages and reproductive failure. The toxicity of SiO₂ and Al₂O₃ nanoparticles is due to their binding to the insect cuticle, followed by physico-sorption of waxes and lipids, leading to insect dehydration. In the final section, insect nanotoxicology research trends are critically discussed, outlining major challenges to predict the ecotoxicological consequences arising from the real-world use of nanoparticles as pesticides.

https://ift.tt/2H4qsnj

Editorial Board

Publication date: 1 June 2018
Source:Appetite, Volume 125





https://ift.tt/2Jb49gm

UVΑ pre-irradiation to P25 titanium dioxide nanoparticles enhanced its toxicity towards freshwater algae Scenedesmus obliquus

Abstract

There has recently been an increase in the usage of TiO₂ nanoparticles (NPs). P25 TiO₂ NPs, a mixture of anatase and rutile phase in 3:1 ratio, are generally used for photocatalytic applications because both phases exhibit a synergistic effect on the photocatalytic activity of the TiO₂ NPs. In the present study, increased toxicity of UVA-pre-irradiated P25 TiO₂ NPs on freshwater algae Scenedesmus obliquus was assessed under visible light and dark exposure conditions at actual low concentrations (0.3, 3 and 35 μM of Ti). Photocatalytic property of P25 TiO₂ NPs caused disaggregation of UVA-pre-irradiated NPs, thus significantly decreasing the mean hydrodynamic diameter (MHD) (188.74 ± 0.54 nm) than that of non-irradiated NPs (232.26 ± 0.44). This decrease in diameter of UVA-pre-irradiated NPs may increase its biological activity towards algal samples. All concentrations of pre-irradiated NPs, under both light and dark conditions, showed a significantly lesser cell viability (p < 0.001) when compared with non-irradiated NPs. Increased production of ROS, antioxidant enzymes and lipid peroxidation supported the viability data. Higher exopolysaccharide production and more nuclear damage were observed for pre-irradiated NPs. NP uptake was also more for the pre-irradiated NPs on treated samples when compared with non-irradiated NPs on treated samples, which, in turn, established the higher toxic potential of UVA-pre-irradiated TiO₂ NPs. This study improves our understanding of the toxic effects of UVA-pre-irradiated TiO₂ NPs on freshwater algae, thereby emphasising the need for ecological risk assessments of metal oxide nanoparticles in a natural experimental medium.

https://ift.tt/2q2rRm7

Immunocompetence analysis of the aquatic snail Lymnaea stagnalis exposed to urban wastewaters

Abstract

Wastewater treatment plant effluents from urban area are a well-known source of chronic multiple micropollution to the downstream living organisms. In this study, ecologically relevant laboratory-bred freshwater gastropods, Lymnaea stagnalis, were exposed for 29 days to raw effluents of a wastewater treatment plant in Lyon area (France). A time-course analysis of individual markers of immunocompetence (hemocyte density and viability, hemocyte NADPH activity, phenol oxidase activity, and capacity of phagocytosis) has shown slight trends of inflammatory-like responses induced by the 100% effluents. So far, no short-term hazard for L. stagnalis can be revealed. However, over the long term, such environmental stress-stimulating immune responses could provoke deleterious life history trade-offs because the immune system is known to be highly energy-consuming.

https://ift.tt/2JaXL8S

Experimental assessment and validation of quantification methods for cellulose content in municipal wastewater and sludge

Abstract

Cellulose, mostly in the form of toilet paper, forms a major component of the particulates in raw municipal wastewater, which could lead to significant consequences due to the potential accumulation of cellulosic fibers and slow biodegradability. Despite the sparse reports on cellulose content and degradation in wastewater and sludge, an accurate and validated method for its quantification in such matrices does not exist. In this paper, four different methods were compared including dilute acid hydrolysis, concentrated acid hydrolysis, enzymatic hydrolysis, and the Schweitzer reagent method. The Schweitzer reagent method, applied to municipal wastewater and sludge, was found to be a very robust and reliable quantification method in light of its reproducibility, accuracy, and ideal (100%) recovery. The determination of cellulose content is critical to understand its fate in wastewater treatment plants as well as improve sludge management and enhance resource recovery.

https://ift.tt/2q0JVxc

The STAT3 Target Gene TNFRSF1A Modulates the NF-κB Pathway in Breast Cancer Cells

Publication date: May 2018
Source:Neoplasia, Volume 20, Issue 5
Author(s): Susana P. Egusquiaguirre, Jennifer E. Yeh, Sarah R. Walker, Suhu Liu, David A. Frank
The transcription factor STAT3 is activated inappropriately in 70% of breast cancers, most commonly in triple negative breast cancer (TNBC). Although the transcriptional function of STAT3 is essential for tumorigenesis, the key target genes regulated by STAT3 in driving tumor pathogenesis have remained unclear. To identify critical STAT3 target genes, we treated TNBC cell lines with two different compounds that block STAT3 transcriptional function, pyrimethamine and PMPTP. We then performed gene expression analysis to identify genes whose expression is strongly down-regulated by both STAT3 inhibitors. Foremost among the down-regulated genes was TNFRSF1A, which encodes a transmembrane receptor for TNFα. We showed that STAT3 binds directly to a regulatory region within the TNFRSF1A gene, and that TNFRSF1A levels are dependent on STAT3 function in both constitutive and cytokine-induced models of STAT3 activation. Furthermore, TNFRSF1A is a major mediator of both basal and TNFα-induced NF-κB activity in breast cancer cells. We extended these findings to primary human breast cancers, in which we found that high TNFRSF1A transcript levels correlated with STAT3 activation. In addition, and consistent with a causal role, increased TNFRSF1A expression was associated with an NF-κB gene expression in signature in breast cancers. Thus, TNFRSF1A is a STAT3 target gene that regulates the NF-κB pathway. These findings reveal a novel functional crosstalk between STAT3 and NF-κB signaling in breast cancer. Furthermore, elevated TNFRSF1A levels may predict a subset of breast tumors that are sensitive to STAT3 transcriptional inhibitors, and may be a biomarker for response to inhibition of this pathway.



https://ift.tt/2GuSuHD

Effect of Low-Dose Versus Standard-Dose Ticagrelor and Clopidogrel on Platelet Inhibition in Acute Coronary Syndromes

https://ift.tt/2JeKADN

TLR4 in Atherogenesis: Paying the Toll for Antimicrobial Defense

https://ift.tt/2JdJqsn

Lack of Association Between Heart Failure and Incident Cancer

AbstractBackground

Several recent studies have suggested an increased cancer risk among patients with heart failure (HF). However, these studies are constrained by limited size and follow-up, lack of comprehensive data on other health attributes, and adjudicated cancer outcomes.

Objectives

This study sought to determine whether HF is associated with cancer incidence and cancer-specific mortality.

Methods

The study assembled a cohort from the Physicians' Health Studies I and II, 2 randomized controlled trials of aspirin and vitamin supplements conducted from 1982 to 1995 and from 1997 to 2011, respectively, that included annual health evaluations and determination of cancer and HF diagnoses. In the primary analysis, the study excluded participants with cancer or HF at baseline and performed multivariable-adjusted Cox models to determine the relationship between HF and cancer, modeling HF as a time-varying exposure. In a complementary analysis, the study used the landmark method and identified cancer-free participants at 70 years of age, distinguishing between those with and without HF, and likewise performed Cox regression. Sensitivity analyses were performed at 65, 75, and 80 years of age.

Results

Among 28,341 Physicians' Health Study participants, 1,420 developed HF. A total of 7,363 cancers developed during a median follow-up time of 19.9 years (25th to 75th percentile: 11.0 to 26.8 years). HF was not associated with cancer incidence in crude (hazard ratio: 0.92; 95% confidence interval: 0.80 to 1.08) or multivariable-adjusted analysis (hazard ratio: 1.05; 95% confidence interval: 0.86 to 1.29). No association was found between HF and site-specific cancer incidence or cancer-specific mortality after multivariable adjustment. Results were similar when using the landmark method at all landmark ages.

Conclusions

HF is not associated with an increased risk of cancer among male physicians.

https://ift.tt/2q2VGD0

JACC Instructions for Authors

https://ift.tt/2JdJDf9

Impact of Heart Failure on Cancer Incidence: A Complicated Question

https://ift.tt/2JelncX

A Changing Landscape in Cardiovascular Research Publication Output: Bridging the Translational Gap

Abstract

The concern about predominance of basic discovery research and lack of translation into clinical medicine, and segregation between these research communities, led the authors to study these research communities through mapping networks of publications and cross-references. Cardiovascular research from 1993 to 2013 was published in 565 journals, including 104 new journals. Only 50% were published in core cardiovascular journals, such as the Journal of the American College of Cardiology, whereas one-half of cardiovascular publications were found in broader biomedical/multidisciplinary journals. The growth of the clinical journal community and merging into one broad journal community suggests a decreasing dichotomy between basic/preclinical and clinical research, potentially contributing to bridging the translational gap.

https://ift.tt/2JdJngb

Delayed Coronary Obstruction After Transcatheter Aortic Valve Replacement

AbstractBackground

Delayed coronary obstruction (DCO) is an uncommon and barely reported complication following transcatheter aortic valve replacement (TAVR).

Objectives

The aim of this study was to describe the incidence and pathophysiological features of DCO after TAVR, obtained from a large international multicenter registry.

Methods

Data were retrospectively collected from an international multicenter registry consisting of 18 centers between November 2005 and December 2016.

Results

During the study period, 38 DCO (incidence 0.22%) cases were identified from a total of 17,092 TAVR procedures. DCO occurred more commonly after valve-in-valve procedures (0.89% vs. 0.18%; p < 0.001) and if self-expandable valves were used during the index procedure (0.36% vs. 0.11% balloon expandable; p < 0.01). DCO was most likely to occur ≤24 h after the TAVR procedure (47.4%; n = 18); 6 (15.8%) cases occurred between 24 h and ≤7 days, with the remaining 14 (36.8%) at ≥60 days. The most frequent presentation was cardiac arrest (31.6%; n = 12), followed by ST-segment elevation myocardial infarction (23.7%; n = 9). The left coronary artery was obstructed in most cases (92.1%; n = 35). Percutaneous coronary intervention was attempted in the majority of cases (74.3% left main; 60% right coronary), and stent implantation was successful in 68.8%. The overall in-hospital death rate was 50% (n = 19), and was higher if DCO occurred ≤7 days from the index procedure (62.5% vs. 28.6%; p = 0.09).

Conclusions

DCO following TAVR is a rare phenomenon that is associated with a high in-hospital mortality rate. Clinicians should be aware that coronary obstruction can occur after the original TAVR procedure and have a low threshold for performing coronary angiography when clinically suspected.

https://ift.tt/2pZenaO

The Role of Salt Reduction in the Management of Hypertension

https://ift.tt/2Grh3co

Delayed Coronary Obstruction After TAVR: A Call for Vigilance

https://ift.tt/2GtaENY

Chlamydia and Lipids Engage a Common Signaling Pathway That Promotes Atherogenesis

AbstractBackground

Recent studies indicate that Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) signaling promote the development of high fat diet–induced atherosclerosis in hypercholesterolemic mice.

Objectives

The authors investigated the role of TLR4/MyD88 signaling in hematopoietic and stromal cells in the development and infection-mediated acceleration of atherosclerosis.

Methods

The authors generated bone marrow chimeras between wild-type and Tlr4^–/– mice, as well as wild-type and Myd88^–/– mice. All mice were on the Apoe^–/– background and fed high fat diet. The authors infected the chimeric mice with C. pneumoniae (CP) and fed them high fat diet.

Results

Aortic sinus plaques and lipid content were significantly reduced in Apoe^–/– mice that received Tlr4^–/–or Myd88^–/– bone marrow compared with control animals despite similar cholesterol levels. Similarly, Tlr4 or Myd88 deficiency in stromal cells also led to a reduction in the lesion area and lipid in aortic sinus plaques. MyD88 expression only in CD11c+ dendritic cells (myeloid cells) in cells was sufficient in otherwise MyD88-deficient mice to induce CP infection–mediated acceleration of atherosclerosis, underlining the key role of MyD88 in CD11c+ dendritic cells (myeloid cells). Whereas CP infection markedly accelerated atherosclerosis in TLR4- or MyD88-positive chimeras, CP infection had a minimal effect on atherosclerosis in TLR4- or MyD88-deficient mice (either in the hematopoietic or stromal cell compartments).

Conclusions

The authors show that both CP infection and metabolic stress associated with dyslipidemia use the same innate immune response pathway, utilizing TLR4/MyD88 signaling, with similar relative contributions in bone marrow–derived hematopoietic cells and in stromal cells. Further studies are required to understand this intricate and complex cross talk among innate and adaptive immune systems in various conditions to more effectively design dendritic cell–mediated atheroprotective vaccines and other therapeutic strategies.

https://ift.tt/2q1Qm2T

Device-Related Thrombosis After Percutaneous Left Atrial Appendage Occlusion for Atrial Fibrillation

AbstractBackground

Transcatheter left atrial appendage (LAA) occlusion is an alternative strategy for stroke prevention in patients with atrial fibrillation (AF).

Objectives

This study sought to determine the incidence, predictors, and prognosis of thrombus formation on devices in patients with AF who were treated with LAA closure.

Methods

The study retrospectively analyzed data from patients treated with 2 LAA closure devices seen in 8 centers in France from February 2012 to January 2017.

Results

A total of 469 consecutive patients with AF underwent LAA closure (272 Watchman devices [Atritech, Boston Scientific, Natick, Massachusetts] and 197 Amplatzer devices [St. Jude Medical, Minneapolis, Minnesota]). Mean follow-up was 13 ± 13 months, during which 339 (72.3%) patients underwent LAA imaging at least once. There were 98 major adverse events (26 thrombi on devices, 19 ischemic strokes, 2 transient ischemic attacks, 18 major hemorrhages, 33 deaths) recorded in 89 patients. The incidence of device-related thrombus in patients with LAA imaging was 7.2% per year. Older age (hazard ratio [HR]: 1.07 per 1-year increase; 95% confidence interval [CI]: 1.01 to 1.14; p = 0.02) and history of stroke (HR: 3.68; 95% CI: 1.17 to 11.62; p = 0.03) were predictors of thrombus formation on the devices, whereas dual antiplatelet therapy (HR: 0.10; 95% CI: 0.01 to 0.76; p = 0.03) and oral anticoagulation at discharge (HR: 0.26; 95% CI: 0.09 to 0.77; p = 0.02) were protective factors. Thrombus on the device (HR: 4.39; 95% CI: 1.05 to 18.43; p = 0.04) and vascular disease (HR: 5.03; 95% CI: 1.39 to 18.23; p = 0.01) were independent predictors of ischemic strokes and transient ischemic attacks during follow-up.

Conclusions

Thrombus formation on the device is not uncommon in patients with AF who are treated by LAA closure. Such events are strongly associated with a higher risk of ischemic stroke during follow-up. (REgistry on Real-Life EXperience With Left Atrial Appendage Occlusion [RELEXAO]; NCT03279406)

https://ift.tt/2pZem6K

Respiratory Syncytial Virus and Associations With Cardiovascular Disease in Adults

Abstract

Respiratory syncytial virus (RSV) is historically known for causing respiratory illness in young children, but the appreciation of its impact on older adults is growing. Studies have shown that hospitalization for respiratory illness due to RSV is complicated by cardiovascular events in 14% to 22% of adult patients, including worsening congestive heart failure, acute coronary syndrome, and arrhythmias. Additionally, underlying cardiovascular disease is associated with hospitalization in 45% to 63% of adults with confirmed RSV. In summary, patients with cardiopulmonary disease have higher rates of health care utilization for RSV-related illness and worse outcomes. Patients with cardiovascular disease likely represent an important target population for the rapidly developing field of RSV vaccines.

https://ift.tt/2q1QkrN

Left Atrial Appendage Occlusion Device-Related Thrombus: Certainties and Uncertainties

https://ift.tt/2GsYwfN

The Challenge of Identifying and Addressing Psychological Comorbidities

https://ift.tt/2q1Qhw7

Elevated Cardiac Troponin T in Patients With Skeletal Myopathies

AbstractBackground

Cardiac troponins are often elevated in patients with skeletal muscle disease who have no evidence of cardiac disease.

Objectives

The goal of this study was to characterize cardiac troponin concentrations in patients with myopathies and derive insights regarding the source of elevated troponin T measurements.

Methods

Cardiac troponin T (cTnT) and cardiac troponin I (cTnI) concentrations were determined by using high sensitivity assays in 74 patients with hereditary and acquired skeletal myopathies. Patients underwent comprehensive cardiac evaluation, including 12-lead electrocardiogram, 24-h electrocardiogram, cardiac magnetic resonance imaging, and coronary artery computed tomography. cTnT and cTnI protein expression was determined in skeletal muscle samples of 9 patients and in control tissues derived from autopsy using antibodies that are used in commercial assays. Relevant Western blot bands were subjected to liquid chromatography tandem mass spectrometry for protein identification.

Results

Levels of cTnT (median: 24 ng/l; interquartile range: 11 to 54 ng/l) were elevated (>14 ng/l) in 68.9% of patients; cTnI was elevated (>26 ng/l) in 4.1% of patients. Serum cTnT levels significantly correlated with creatine kinase and myoglobin (r = 0.679 and 0.786, respectively; both p < 0.001). Based on cTnT serial testing, 30.1% would have fulfilled current rule-in criteria for myocardial infarction. Noncoronary cardiac disease was present in 23%. Using cTnT antibodies, positive bands were found in both diseased and healthy skeletal muscle at molecular weights approximately 5 kDa below cTnT. Liquid chromatography tandem mass spectrometry identified the presence of skeletal troponin T isoforms in these bands.

Conclusions

Measured cTnT concentrations were chronically elevated in the majority of patients with skeletal myopathies, whereas cTnI elevation was rare. Our data indicate that cross-reaction of the cTnT immunoassay with skeletal muscle troponin isoforms was the likely cause.

https://ift.tt/2q1Qn6X

Admissions for Infective Endocarditis in Intravenous Drug Users

https://ift.tt/2pZeeUO

Science Moves Slowly

https://ift.tt/2GsYvbJ

Reply: The Role of Salt Reduction in the Management of Hypertension

https://ift.tt/2q1QejV

A Study of Optical Imaging With Light From Radiotracers in Cancer Patients

Condition:   Thyroid Cancer
Intervention:   Diagnostic Test: Cerenkov luminescence imaging.
Sponsor:   Memorial Sloan Kettering Cancer Center
Recruiting

https://ift.tt/2ImIfp3

Efficacy and Safety Study of Tisotumab Vedotin for Patients With Solid Tumors

Conditions:   Colorectal Neoplasms;   Carcinoma, Non-Small-Cell Lung;   Exocrine Pancreatic Cancer;   Carcinoma, Squamous Cell of Head and Neck
Intervention:   Drug: tisotumab vedotin
Sponsors:   Seattle Genetics, Inc.;   Genmab
Not yet recruiting

https://ift.tt/2GLIXPI

Assessment and Prediction of Cetuximab-Induced Hypersensitivity Reactions Using Cetuximab Specific IgE Detection

Conditions:   Tumor Disease Including Colorectal Cancer;   Head & Neck Squamous Cell Carcinoma
Intervention:  
Sponsor:   Yonsei University
Recruiting

https://ift.tt/2Ee2naK

Issue Information

Dermatologic Therapy, Volume 31, Issue 2, March/April 2018.


https://ift.tt/2pYgXxZ

A comprehensive air quality investigation at an aquatic centre: Indoor/outdoor comparisons

Abstract

Air quality and comfort parameters in a naturally ventilated aquatic centre were studied in relation to the outdoor pollution levels. Simultaneous measurements of PM 2.5, as well as of volatile organic compounds, were carried out for the indoor and outdoor environment of the aquatic centre. The chemical analysis of ionic species and trace elements associated with particulate matter was also performed. In addition, automated analyzer for NO₂ and O₃ was used in order to record the indoor and outdoor levels of these pollutants. Analysis of diurnal variation of the pollutants' concentration was applied to the collected data, allowing the identification of potential variation on the sources affecting the indoor air quality. PM 2.5 concentration was almost two times higher indoors than outdoors with average values of 13.96 and 6.78 μg/m³, respectively. Concerning the ion fraction of PM 2.5, SO₄²⁻ and Ca²⁺ were the ions with higher concentration indoors with values of 1.06 and 0.93 μg/m³, respectively, while the percentage of Cl⁻ to the PM 2.5 fraction of the indoor atmosphere (9%) was too high than outdoor ones (1%). These results showed that indoor air of swimming pool concerning PM 2.5 and ionic species is mainly affected by the chlorination process along with the comfort conditions (high relative humidity) created during the operation of the facility. The common volatile organic compound concentrations at indoor air are generally in higher levels, compared to the outdoor air with p,m-xylene and toluene to be the substances with the higher concentration for indoor and outdoor area, respectively (7.80 and 1.57 μg/m³); nevertheless, values were rather low compared with the findings of other studies. Also, they clearly demonstrate a diurnal variation as a result of poor ventilation during night. As it was expected, chloroform showed the highest concentration compared to the other volatile organic compounds with values ranging from 3.35 to 135.89 μg/m³, with an average of 54.50 μg/m³. Concerning the NO₂ concentration, indoor levels showed an increased pattern when the swimming pool was fully occupied, a fact that reveals a possible correlation. As an overall conclusion, the natural ventilation and the disinfection process seem to play a key role to the air quality of the indoor air of the aquatic centre.

https://ift.tt/2H3jWwX

Morphological and functional responses of a metal-tolerant sunflower mutant line to a copper-contaminated soil series

Abstract

The potential use of a metal-tolerant sunflower mutant line for biomonitoring Cu phytoavailability, Cu-induced soil phytotoxicity, and Cu phytoextraction was assessed on a Cu-contaminated soil series (13–1020 mg Cu kg⁻¹) obtained by fading a sandy topsoil from a wood preservation site with a similar uncontaminated soil. Morphological and functional plant responses as well as shoot, leaf, and root ionomes were measured after a 1-month pot experiment. Hypocotyl length, shoot and root dry weight (DW) yields, and leaf area gradually decreased as soil Cu exposure rose. Their dose-response curves (DRC) plotted against indicators of Cu exposure were generally well fitted by sigmoidal curves. The half-maximal effective concentration (EC₅₀) of morphological parameters ranged between 203 and 333 mg Cu kg⁻¹ soil, corresponding to 290–430 μg Cu L⁻¹ in the soil pore water, and 20 ± 5 mg Cu kg⁻¹ DW in the shoots. The EC₁₀ for shoot Cu concentration (13–15 mg Cu kg⁻¹ DW) coincided to 166 mg Cu kg⁻¹ soil. Total chlorophyll content and total antioxidant capacity (TAC) were early biomarkers (EC₁₀: 23 and 51 mg Cu kg⁻¹ soil). Their DRC displayed a biphasic response. Photosynthetic pigment contents, e.g., carotenoids, correlated with TAC. Ionome was changed in Cu-stressed roots, shoots, and leaves. Shoot Cu removal peaked roughly at 280 μg Cu L⁻¹ in the soil pore water.

https://ift.tt/2JaZMlD

Controls on the spatial distribution of iodine in groundwater in the Hebei Plain, China

Abstract

In the Hebei Plain of North China, 70% of the inhabitants depend on groundwater for drinking water. Little is known regarding high-iodine concentrations in groundwater because there have been few systematic studies on high levels of iodine in groundwater in this region. To help identify the mechanisms that control the spatial distribution of iodine in groundwater, 61 samples of shallow groundwater and 161 samples of deep groundwater were collected along a sample section from Taihang Mountain to the Bo Sea. There were four pockets of high-iodine concentrations along the sample section. As the groundwater depth increased, the ratio of undetected iodine decreased, and the ratio of high-iodine concentrations increased. The high-iodine concentrations in the groundwater reflect the geological and sedimentary settings, and were mainly controlled by pH and Eh. Iodine concentrations were particularly high when the pH was between 7.3 and 8.5, and there was an inflection point at 150 μg/L in the curve of the relationship between iodine concentrations and Eh.

https://ift.tt/2Gwryax

Increased cortisol metabolism in women with pregnancy-related hypertension

Abstract

Purpose

The diminished function of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2) was found in placentae from preeclamptic pregnancies. Here, we examine the overall maternal glucocorticoid balance in pregnancy-related hypertension. We aim to answer the question if the functions of primary enzymes involved in cortisol metabolism: 11β-HSD1 and 11β-HSD2 and 5-reductases (both 5α- and 5β) are altered in the course of hypertensive pregnancy.

Methods

We determined plasma and urinary cortisol and cortisone as well as their urinary tetrahydro- and allo-tetrahydrometabolites, both in free and conjugated forms in samples obtained from 181 Polish women in the third trimester of pregnancy. We compared steroid profiles in women with preeclampsia (PE), gestational hypertension (GH), chronic hypertension (CH) and in normotensives (controls).

Results

We found significant differences in glucocorticoid balance in pregnancy-related hypertension. Plasma cortisol to cortisone was significantly lower in PE than in controls (3.00 vs. 4.79; p < 0.001). Increased function of renal 11β-HSD2 in PE and GH was manifested by significantly lower urinary free cortisol to cortisone ratio (0.169 and 0.206 vs. 0.277 in controls; p < 0.005). Markedly enhanced metabolism of cortisol was observed in pregnancy-related hypertension, with no significant alterations in CH, and the changes were more clearly expressed in PE than in GH.

Conclusions

The glucocorticoid balance in PE and GH is shifted towards decreasing cortisol concentration either due to intensified conversion to cortisone or enhanced production of tetrahydro and allo-tetrahydrometabolites.

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