Crystal structure and mechanical properties of a new ternary phase in Mg-Zn-Y alloy solidified under high pressure

Publication date: 15 September 2017
Source:Journal of Alloys and Compounds, Volume 717
Author(s): Wei Jiang, Chunming Zou, Haw-Tyng Huang, Zheng Ran, Zunjie Wei
A new ternary phase, Mg64.093±0.004Zn15.355±0.002Y20.552±0.005 (at. %) was found in a Mg-Zn-Y alloy prepared by high pressure solidification. A full set of crystal structure parameters including the atomic coordinates of this new phase were determined using X-ray diffraction with Rietveld refinement and electron probe micro-analysis. Furthermore, the mechanical properties of this phase, including the Young's modulus and hardness were reported by nanoindentation test. Theoretical elastic constants, bulk modulus, shear modulus, Young's modulus, Poisson's ratio of this phase were calculated by first-principles. Results indicate that this phase is a ductile materials phase.

Graphical abstract

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Stable isotope ratio and elemental composition parameters in combination with discriminant analysis classification model to assign country of origin to commercial vegetables – A preliminary study

Publication date: October 2017
Source:Food Control, Volume 80
Author(s): Anja Mahne Opatić, Marijan Nečemer, Sonja Lojen, Rajko Vidrih
Recently, increased public attention has been paid to the geographical authentication of food, including vegetables, which are considered to be one of the major health-promoting components in a balanced diet. The purpose of the present study was to investigate the suitability of the use of isotopic compositions of light elements (δ¹³C, δ¹⁵N, δ¹⁸O, δ³⁴S) in combination with multi-elemental fingerprinting (P, S, Cl, K, Ca, Mn, Fe, Zn, Br, Rb, Sr) to provide rapid, robust and inexpensive screening methods for distinguishing lettuce, sweet pepper, and tomato samples according to their given country of origin (i.e., Slovenia, Austria, Spain, Morocco, Italy, Greece), and thus ensuring their traceability in terms of their authenticity. The classification efficiency of the proposed multivariate statistical models using supervised pattern-recognition analysis, namely multivariate discriminant analysis, was sufficient for rapid and robust screening purpose. The predictions of the suggested discriminant analysis models per kind using cross-validation leave-one-out were 86.2%, 71.1% and 74.4% for lettuce, sweet pepper and tomato, respectively. The first use of the proposed methodology on vegetable samples on European and Mediterranean scales provides a valuable and necessary contribution to the development and implementation of a new national surveillance system that can be used to trace the geographical origins of vegetables.



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Preparation and characterization of magnetic biosorbent based on oil palm empty fruit bunch fibers, cellulose and Ceiba pentandra for heavy metal ions removal

Publication date: 15 October 2017
Source:Industrial Crops and Products, Volume 105
Author(s): S. Daneshfozoun, M.A. Abdullah, B. Abdullah
This study prepared, characterized and developed agro-based magnetic biosorbents (AMBs) from Ceiba pentandra (RKF), oil palm empty fruit bunches (EFB) and celluloses (CEL) extracted from EFB, using a novel, simple and cost-effective preparation technique for the removal of Pb(II), Cu(II), Zn(II), Mn(II) and Ni(II) ions from aqueous solutions. There has been no report on the methods to prepare and the use of magnetic biosorbent based on these biomaterials. The morphological, chemical and magnetic characterization suggested successful preparation of AMBs with good dispersion of magnetic nanoparticles on the surface of the base materials with clear magnetic properties. Optimum sorption was achieved between pH 5–7, and increase in initial ion concentration and solution temperature resulted in increased ion uptake. AMBs regeneration was successfully performed for 5 adsorption/desorption cycles. The magnetic biosorbent based on kapok showed the best Pb(II) removal efficiency of 99.4% and 49mg/g adsorption capacity compared to 98.2% for cellulose and 97.7% for EFB. The magnetic biosorbents exhibited 10.3% higher removal efficiency than the raw sorbents.



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On the eutectoid transformation behavior of the Ti-Zn system and its metastable phases

Publication date: 25 September 2017
Source:Journal of Alloys and Compounds, Volume 718
Author(s): D.A. Brice, P. Samimi, I. Ghamarian, Y. Liu, M.Y. Mendoza, M.J. Kenney, R.F. Reidy, M. Garcia-Avila, P.C. Collins
To date, Zn has not been used as an alloying addition in structural Ti alloys. The main obstacle has been the disparity between their melting and vaporization temperatures. A novel processing technique was developed to create a Ti-Zn compound. The equilibrium phases and microstructures were studied by electron microscopy and x-ray diffraction techniques. Results show the presence of pearlitic domains of α-Ti (hexagonal closed packed crystal structure) and Ti2Zn (body center tetragonal structure) in regions that have a near eutectoid composition. Solutionizing and water quenching results in the formation of martensite along with intermetallic laths, suggesting that the eutectoid transformation is active.

Graphical abstract

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Role for RIF1-Interacting Partner DDX1 in BLM Recruitment to DNA Double-Strand Breaks

Publication date: Available online 13 May 2017
Source:DNA Repair
Author(s): Lei Li, Ho-Yin Poon, Matthew R. Hildebrandt, Elizabeth A. Monckton, Devon R. Germain, Richard P. Fahlman, Roseline Godbout
Human Rap1-interacting factor 1 (RIF1) is an important player in the repair of DNA double strand breaks (DSBs). RIF1 acts downstream of 53BP1, with well-documented roles in class switch recombination in B-cells and inhibition of end resection initiation in BRCA1-defective cells. Here, we report that DEAD Box 1 (DDX1), a RNA helicase also implicated in DSB repair, interacts with RIF1, with co-localization of DDX1 and RIF1 observed throughout interphase. Recruitment of DDX1 to DSBs is dependent on RIF1, with RIF1 depletion abolishing DDX1-mediated facilitation of homologous recombination at DSBs. As previously demonstrated for RIF1, DDX1 is also required for chromatin loading of Bloom syndrome helicase (BLM) to ionizing radiation-induced DSBs, a RIF1-related activity that is independent of 53BP1. We show that DDX1 and RIF1 have different nucleic acid requirements for accumulation at DSBs, with RNA-DNA hybrids required for DDX1 accrual at DSBs, and single-strand RNA required for accumulation of RIF1 at these sites. Our data suggest both convergent and divergent roles for RIF1 in DSB repair, and may help to explain why RIF1 depletion does not fully mimic 53BP1 ablation in the restoration of homologous recombination defects in BRCA1-deficent cells.



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Five-year outcomes of an oropharynx-directed treatment approach for unknown primary of the head and neck

Publication date: July 2017
Source:Oral Oncology, Volume 70
Author(s): Kenneth Shung Hu, Waleed Fouad Mourad, Mauricio E. Gamez, Wilson Lin, Adam Saul Jacobson, Mark Stephen Persky, Mark L. Urken, Bruce E. Culliney, Zujun Li, Theresa Nguyen Tran, Stimson Pryor Schantz, Juskaran Chadha, Louis Benjamin Harrison
PurposeSquamous cell carcinoma of unknown primary (SCCHNUP) is commonly treated with comprehensive radiation to the laryngopharynx and bilateral necks. In 1998, we established a departmental policy to treat SCCHNUP with radiation directed to the oropharynx and bilateral neck.MethodsFrom 1998–2011, 60 patients were treated – N1: 18%, N2: 75% and N3: 7%. 82% underwent neck dissection. 55% received IMRT and 62% underwent concurrent chemoradiotherapy.ResultsAt median follow-up of 54months, 5 patients failed regionally and 4 emerged with a primary (tongue base, hypopharynx and thoracic esophagus). Five-year rates of regional control, primary emergence, distant metastasis, disease-free survival and overall survival were 90%, 10%, 20%, 72% and 79%, respectively. The 5year rate of primary emergence in a non-oropharynx site was 3%.ConclusionThis is the first demonstration that an oropharynx-directed approach yields low rates of primary emergence in SCCHNUP with excellent oncologic outcomes.



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Macrophage polarization differs between apical granulomas, radicular cysts, and dentigerous cysts

Abstract

Objectives

Apical periodontitis can appear clinically as apical granulomas or radicular cysts. There is evidence that immunologic factors are involved in the pathogenesis of both pathologies. In contrast to radicular cysts, the dentigerous cysts have a developmental origin. Macrophage polarization (M1 vs M2) is a main regulator of tissue homeostasis and differentiation. There are no studies comparing macrophage polarization in apical granulomas, radicular cysts, and dentigerous cysts.

Materials and methods

Forty-one apical granulomas, 23 radicular cysts, and 23 dentigerous cysts were analyzed in this study. A tissue microarray (TMA) of the 87 consecutive specimens was created, and CD68-, CD11c-, CD163-, and MRC1-positive macrophages were detected by immunohistochemical methods. TMAs were digitized, and the expression of macrophage markers was quantitatively assessed.

Results

Radicular cysts are characterized by M1 polarization of macrophages while apical granulomas show a significantly higher degree of M2 polarization. Dentigerous cysts have a significantly lower M1 polarization than both analyzed periapical lesions (apical granulomas and radicular cysts) and accordingly, a significantly higher M2 polarization than radicular cysts. Macrophage cell density in dentigerous cysts is significantly lower than in the periapical lesions.

Conclusions

The development of apical periodontitis towards apical granulomas or radicular cysts might be directed by macrophage polarization. Radicular cyst formation is associated with an increased M1 polarization of infiltrating macrophages. In contrast to radicular cysts, dentigerous cysts are characterized by a low macrophage infiltration and a high degree of M2 polarization, possibly reflecting their developmental rather than inflammatory origin.

Clinical relevance

As M1 polarization of macrophages is triggered by bacterial antigens, these results underline the need for sufficient bacterial clearance during endodontic treatment to prevent a possible M1 macrophage-derived stimulus for radicular cyst formation.

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Chromane isolated from leaves of Dillenia indica improves the neuronal dysfunction in STZ-induced diabetic neuropathy

Publication date: Available online 13 May 2017
Source:Journal of Ethnopharmacology
Author(s): Navpreet Kaur, Lalit Kishore, Randhir Singh
Ethnopharmacological relevanceAccording to the Indian traditional medicine, Dillenia indica L. has shown therapeutic efficacy in various diseases. Fruits and leaves of the plant possess anti-oxidant and anti-inflammatory properties. Reactive oxygen species, formation of advanced glycation end products (AGEs) and apoptosis are implicated in the pathogenesis of diabetic neuropathy.Aim of the studyThe aim of the present study was to explore the effect of D. indica and its isolate, chromane (CR), on thermal and mechanical hyperalgesia, allodynia, MNCV and oxidative-nitrosative stress in streptozotocin-induced experimental diabetes.Material and MethodsDiabetes was induced by intraperitoneal administration of Streptozotocin (STZ; 65mg/kg) for the development of diabetic neuropathy. Chronic treatment with DAE (100, 200 and 400mg/kg, p.o.) and CR (5 and 10mg/kg, p.o.) for 30 days was started from the 60^th day of STZ administration. Development of neuropathy was evident from a marked hyperalgesia and allodynia; reduced MNCV associated with increased formation of AGEs and reactive oxygen species.Resultssignificantly attenuated behavioral and biochemical changes associated with diabetic neuropathy. Present study suggested that DAE and CR ameliorated hyperglycemia and diabetic neuropathic pain via modulation of oxidative-nitrosative stress and reduction in AGEs formation in the diabetic rats.ConclusionThus D. indica might be beneficial in chronic diabetics, ameliorate the progression of diabetic neuropathy and may also find application in diabetic neuropathic pain.

Graphical abstract

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Coordinated regulation of IFITM1, 2 and 3 genes by an IFN-responsive enhancer through long-range chromatin interactions

Publication date: Available online 13 May 2017
Source:Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms
Author(s): Ping Li, Ming-Lei Shi, Wen-Long Shen, Zhang Zhang, De-Jian Xie, Xiang-Yuan Zhang, Chao He, Yan Zhang, Zhi-Hu Zhao
Interferon-induced transmembrane protein (IFITM) 1, 2 and 3 are a family of interferon (IFN)-induced transmembrane proteins that block entry of a broad spectrum of pathogens. However, the transcriptional regulation of these genes, especially whether there exists any enhancers and their roles during the IFN induction process remain elusive. Here, combining episomal luciferase reporter assay and in vivo genome editing, we identified an IFNβ-responsive enhancer located 35kb upstream of IFITM3 gene promoter upregulating the IFNβ-induced expression of IFITM1, 2 and 3 genes, thus contributing to IFNβ-mediated resistance to influenza A virus (IAV) infection. The enhancer was first identified and verified by data mining and luciferase reporter assay. Then we showed that signal transducers and activators of transcription (STAT) 1 bound to the enhancer after the treatment of IFNβ and was indispensable for the enhancer activity. Next, CRISPR-Cas9 mediated in vivo truncation of the enhancer considerably decreased both IFNβ and IAV-induced expression of IFTIM1, 2 and 3 in HEK293 cells. Furthermore, chromosome conformation capture revealed that the IFITM1, 2 and 3 genes physically clustered together and constitutively looped to the distal enhancer through long-range interactions in both HEK293 and A549 cells, providing structural basis for coordinated regulation of IFITM1, 2 and 3 by IFNβ. Finally, we showed that in vivo truncation of the enhancer impaired IFNβ-induced resistance to IAV infection. These findings expand our understanding of the mechanisms underlying the transcriptional regulation of IFITM1, 2 and 3 expression and its ability to mediate IFN-β signaling.



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Cell-surface G-protein-coupled receptors for tumor-associated metabolites: A direct link to mitochondrial dysfunction in cancer

Publication date: Available online 13 May 2017
Source:Biochimica et Biophysica Acta (BBA) - Reviews on Cancer
Author(s): Bojana Ristic, Yangzom D. Bhutia, Vadivel Ganapathy
Mitochondria are the sites of pyruvate oxidation, citric acid cycle, oxidative phosphorylation, ketogenesis, and fatty acid oxidation. Attenuation of mitochondrial function is one of the most significant changes that occurs in tumor cells, directly linked to oncogenesis, angiogenesis, Warburg effect, and epigenetics. In particular, three mitochondrial enzymes are inactivated in cancer: pyruvate dehydrogenase (PDH), succinate dehydrogenase (SDH), and 3-hydroxy-3-methylglutaryl CoA synthase-2 (HMGCS2). These enzymes are subject to regulation via acetylation/deacetylation. SIRT3, the predominant mitochondrial deacetylase, directly targets these enzymes for deacetylation and maintains their optimal catalytic activity. SIRT3 is a tumor suppressor, and deacetylation of these enzymes contributes to its biological function. PDH catalyzes the oxidative decarboxylation of pyruvate into acetyl CoA, SDH oxidizes succinate into fumarate, and HMGCS2 controls the synthesis of the ketone body β-hydroxybutyrate. As the activities of these enzymes are decreased in cancer, tumor cells accumulate lactate and succinate but produce less amounts of β-hydroxybutyrate. Apart from their role in cellular energetics, these metabolites function as signaling molecules via specific cell-surface G-protein-coupled receptors. Lactate signals via GPR81, succinate via GPR91, and β-hydroxybutyrate via GPR109A. In addition, lactate activates hypoxia-inducible factor HIF1α and succinate promotes DNA methylation. GPR81 and GPR91 are tumor promoters, and increased production of lactate and succinate as their agonists drives tumorigenesis by enhancing signaling via these two receptors. In contrast, GPR109A is a tumor suppressor, and decreased synthesis of β-hydroxybutyrate as its agonist suppresses signaling via this receptor, thus attenuating the tumor-suppressing function of GPR109A. In parallel with the opposing changes in lactate/succinate and β-hydroxybutyrate levels, tumor cells upregulate GPR81 and GPR91 but downregulate GPR109A. As such, these three metabolite receptors play a critical role in cancer and represent a new class of drug targets with selective antagonists of GPR81 and GPR91 for cancer treatment and agonists of GPR109A for cancer prevention.



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Disparities in cancer stage at diagnosis and survival of Aboriginal and non-Aboriginal South Australians

Publication date: June 2017
Source:Cancer Epidemiology, Volume 48
Author(s): David Banham, David Roder, Dorothy Keefe, Gelareh Farshid, Marion Eckert, Margaret Cargo, Alex Brown
Background/AimThis study tested the utility of retrospectively staging cancer registry data for comparing stage and stage-specific survivals of Aboriginal and non-Aboriginal people. Differences by area level factors were also explored.MethodsThis test dataset comprised 950 Aboriginal cases and all other cases recorded on the South Australian cancer registry with a 1977–2010 diagnosis. A sub-set of 777 Aboriginal cases diagnosed in 1990–2010 were matched with randomly selected non-Aboriginal cases by year of birth, diagnostic year, sex, and primary site of cancer. Competing risk regression summarised associations of Aboriginal status, stage, and geographic attributes with risk of cancer death.ResultsAboriginal cases were 10 years younger at diagnosis, more likely to present in recent diagnostic years, to be resident of remote areas, and have primary cancer sites of head & neck, lung, liver and cervix. Risk of cancer death was associated in the matched analysis with more advanced stage at diagnosis. More Aboriginal than non-Aboriginal cases had distant metastases at diagnosis (31.3% vs 22.0, p<0.001). After adjusting for stage, remote-living Aboriginal residents had higher risks of cancer death than Aboriginal residents of metropolitan areas. Non-Aboriginal cases had the lowest risk of cancer death.ConclusionRetrospective staging proved to be feasible using registry data. Results indicated more advanced stages for Aboriginal than matched non-Aboriginal cases. Aboriginal people had higher risks of cancer death, which persisted after adjusting for stage, and applied irrespective of remoteness of residence, with highest risk of death occurring among Aboriginal people from remote areas.



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Working memory and attentional bias on reinforcing efficacy of food

Publication date: 1 September 2017
Source:Appetite, Volume 116
Author(s): Katelyn A. Carr, Leonard H. Epstein
Reinforcing efficacy of food, or the relationship between food prices and purchasing, is related to obesity status and energy intake in adults. Determining how to allocate resources for food is a decision making process influenced by executive functions. Attention to appetitive cues, as well as working memory capacity, or the ability to flexibly control attention while mentally retaining information, may be important executive functions involved in food purchasing decisions. In two studies, we examined how attention bias to food and working memory capacity are related to reinforcing efficacy of both high energy-dense and low energy-dense foods. The first study examined 48 women of varying body mass index (BMI) and found that the relationship between attentional processes and reinforcing efficacy was moderated by working memory capacity. Those who avoid food cues and had high working memory capacity had the lowest reinforcing efficacy, as compared to those with low working memory capacity. Study 2 systematically replicated the methods of study 1 with assessment of maintained attention in a sample of 48 overweight/obese adults. Results showed the relationship between maintained attention to food cues and reinforcing efficacy was moderated by working memory capacity. Those with a maintained attention to food and high working memory capacity had higher reinforcing efficacy than low working memory capacity individuals. These studies suggest working memory capacity moderated the relationship between different aspects of attention and food reinforcement. Understanding how decision making process are involved in reinforcing efficacy may help to identify future intervention targets.



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Lack of negative autocorrelations of daily food intake on successive days challenges the concept of the regulation of body weight in humans

Publication date: 1 September 2017
Source:Appetite, Volume 116
Author(s): David A. Levitsky, Ji Eun Raea Limb, Lua Wilkinson, Anna Sewall, Yingyi Zhong, Ammar Olabi, Jean Hunter
According to most theories, the amount of food consumed on one day should be negatively related to intake on subsequent days. Several studies have observed such a negative correlation between the amount consumed on one day and the amount consumed two to four days later. The present study attempted to replicate this observation by re-examining data from a previous study where all food ingested over a 30-day observation period was measured. Nine male and seven female participants received a vegan diet prepared, dispensed, and measured in a metabolic unit. Autocorrelations were performed on total food intake consume on one day and that consumed one to five days later. A significant positive correlation was detected between the weight of food eaten on one day and on the amount consumed on the following day (r = 0.29, 95% CI [0.37, 0.20]). No correlation was found between weights of food consumed on one day and up to twelve days later (r = 0.09, 95% CI [0.24, −0.06]), (r = 0.11, 95% CI [0.26, −0.0.26]) (r = 0.02, 95% CI [0.15, −0.7]) (r = −0.08, 95% CI [0.11, −0.09]). The same positive correlation with the previous day's intake was observed at the succeeding breakfast but not at either lunch or dinner. However, the participants underestimated their daily energy need resulting in a small, but statistically significant weight loss. Daily food intake increased slightly (13 g/day), but significantly, across the 30-day period. An analysis of the previous studies revealed that the negative correlations observed by others was caused by a statistical artifact resulting from normalizing data before testing for the correlations. These results, when combined with the published literature, indicate that there is little evidence that humans precisely compensate for the previous day's intake by altering the amount consumed on subsequent days. Moreover, the small but persistent increase in food intake suggests that physiological mechanisms that affect food intake operate more subtly and over much longer periods of time than the meal or even total daily intake.



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LDH inhibition impacts on heat shock response and induces senescence of hepatocellular carcinoma cells

Publication date: 15 July 2017
Source:European Journal of Pharmaceutical Sciences, Volume 105
Author(s): Marcella Manerba, Lorenza Di Ianni, Marzia Govoni, Marinella Roberti, Maurizio Recanatini, Giuseppina Di Stefano
In normal cells, heat shock response (HSR) is rapidly induced in response to a variety of harmful conditions and represents one of the most efficient defense mechanism. In cancer tissues, constitutive activation converts HSR into a life-threatening process, which plays a major role in helping cell survival and proliferation. Overexpression of heat shock proteins (HSPs) has been widely reported in human cancers and was found to correlate with tumor progression. Hepatocellular carcinoma is one of the conditions in which HSR activation was shown to have the highest clinical significance.Transcription of HSPs is induced by HSF-1, which also activates glycolytic metabolism and increases the expression of LDH-A, the master regulator of the Warburg effect. In this paper, we tried to explore the relationship between HSR and LDH-A. In cultured hepatocellular carcinoma cells, by using two enzyme inhibitors (oxamate and galloflavin), we found that the reduction of LDH-A activity led to decreased level and function of the major HSPs involved in tumorigenesis. Galloflavin (a polyphenol) also inhibited the ATPase activity of two of the examined HSPs. Finally, hindering HSR markedly lowered the alpha-fetoprotein cellular levels and induced senescence.Specific inhibitors of single HSPs are currently under evaluation in different neoplastic diseases. However, one of the effects usually observed during treatment is a compensatory elevation of other HSPs, which decreases treatment efficacy. Our results highlight a connection between LDH and HSR and suggest LDH inhibition as a way to globally impact on this tumor promoting process.

Graphical abstract

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Evaluating the predictability of the in vitro transfer model and in vivo rat studies as a surrogate to investigate the supersaturation and precipitation behaviour of different Albendazole formulations for humans

Publication date: 15 July 2017
Source:European Journal of Pharmaceutical Sciences, Volume 105
Author(s): Aaron Ruff, René Holm, Edmund S. Kostewicz
The present study investigated the ability of the in vitro transfer model and an in vivo pharmacokinetic study in rats to investigate the supersaturation and precipitation behaviour of albendazole (ABZ) relative to data from a human intestinal aspiration study reported in the literature. Two lipid based formulation systems, a hydroxypropyl-β-cyclodextrin (HPβCD) solution and the addition of a crystallization inhibitor (HPMC-E5) on the behaviour of ABZ was investigated. These formulations were investigated to represent differences in their ability to facilitate supersaturation within the small intestine. Overall, both the in vitro transfer model and the in vivo rat study were able to rank order the formulations (as aqueous suspension±HPMC<Lipid based formulations<HPβCD-solution) in accordance with the observations in the human aspiration study. The results therefore demonstrated that both the in vivo rat model and the in vitro transfer model could reflect the performance of the ABZ formulations in the human study. Whilst the rat was able to provide information on the overall plasma exposure, through the use of the in vitro transfer model, a more mechanistic understanding of the supersaturation and precipitation behaviour of ABZ using the different formulation strategies, could be attained.

Graphical abstract

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Mechanisms of Immune Tolerance in Leukemia and Lymphoma

Publication date: Available online 13 May 2017
Source:Trends in Immunology
Author(s): Emily K. Curran, James Godfrey, Justin Kline
The mechanisms through which immune responses are generated against solid cancers are well characterized and knowledge of the immune evasion pathways exploited by these malignancies has grown considerably. However, for hematological cancers, which develop and disseminate quite differently than solid tumors, the pathways that regulate immune activation or tolerance are less clear. Growing evidence suggests that, while numerous immune escape pathways are shared between hematological and solid malignancies, several unique pathways are exploited by leukemia and lymphoma. Below we discuss immune evasion mechanisms in leukemia and lymphoma, highlighting key differences from solid tumors. A more complete characterization of the mechanisms of immune tolerance in hematological malignancies is critical to inform the development of future immunotherapeutic approaches.



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E-cigarette liquids: Constancy of content across batches and accuracy of labeling

Publication date: October 2017
Source:Addictive Behaviors, Volume 73
Author(s): Jean-François Etter, Aurélie Bugey
AimsTo assess whether bottles of refill liquids for e-cigarettes were filled true to label, whether their content was constant across two production batches, and whether they contained impurities.MethodsIn 2013, we purchased on the Internet 18 models from 11 brands of e-liquids. We purchased a second sample of the same models 4months later. We analyzed their content in nicotine, anabasine, propylene glycol, glycerol, ethylene glycol and diethylene glycol, and tested their pH.ResultsThe median difference between the nicotine value on the labels and the nicotine content in the bottles was 0.3mg/mL (range −5.4 to +3.5mg/mL, i.e. −8% to +30%). For 82% of the samples, the actual nicotine content was within 10% of the value on the labels. All models contained glycerol (median 407mg/mL), and all but three models contained propylene glycol (median 650mg/mL). For all samples, levels of anabasine, ethylene glycol and diethylene glycol were below our limits of detection. The pH of all the e-liquids was alkaline (median pH=9.1; range 8.1 to 9.9). The measured content of two batches of the same model varied by a median of 0% across batches for propylene glycol, 1% for glycerol, 0% for pH, and 0.5% for nicotine (range −15% to +21%; 5th and 95th percentiles: −15% and +10%).ConclusionsThe nicotine content of these e-liquids matched the labels on the bottles, and was relatively constant across production batches. The content of propylene glycol and glycerol was also stable across batches, as was the pH.



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The social exigencies of the gateway progression to the use of illicit drugs from adolescence into adulthood

Publication date: October 2017
Source:Addictive Behaviors, Volume 73
Author(s): Roy Otten, Chung Jung Mun, Thomas J. Dishion
BackgroundThere is limited empirical integration between peer clustering theory and the Gateway framework. The goal of the present study was to test the hypothesis that friendship associations partly predict gateway escalations in the use of drugs from adolescence to adulthood.MethodThis longitudinal study analyzed 3 waves of data from a community sample of 711 male and female participants without a history of illicit drug use reporting drug use at age 17, 22, and 27. Substance use assessments including tobacco, alcohol, cannabis, onset and abuse/dependence tendency of illicit drugs other than cannabis (i.e., cocaine, methamphetamine, and opiates), and friends' reported use of illicit drugs. Structural equation modeling was used to test the hypothesized model.ResultsParticipants' cannabis use level at age 17 was positively associated with perceived friends' drug use at age 22, which in turn predicted participants' onset of illicit drug use between ages 22 and 27. Moreover, progression of tobacco use throughout age 17 to 22 was associated with an increased onset of illicit drug use between ages 22 and 27. Apart for an effect of cannabis use at age 22 on abuse and dependence tendency to various drugs at age 28, results were similar.ConclusionsDuring this period of development, the availability and selection of drug-using friends contributes to the progression to potentially more rewarding and damaging illicit drugs. These findings suggest the need to attend to the peer ecology in prevention and support the common practice of using abstaining peers in treatment for drug dependence.



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The relationship between social desirability bias and self-reports of health, substance use, and social network factors among urban substance users in Baltimore, Maryland

Publication date: October 2017
Source:Addictive Behaviors, Volume 73
Author(s): Carl A. Latkin, Catie Edwards, Melissa A. Davey-Rothwell, Karin E. Tobin
BackgroundSocial desirability response bias may lead to inaccurate self-reports and erroneous study conclusions. The present study examined the relationship between social desirability response bias and self-reports of mental health, substance use, and social network factors among a community sample of inner-city substance users.MethodsThe study was conducted in a sample of 591 opiate and cocaine users in Baltimore, Maryland from 2009 to 2013. Modified items from the Marlowe-Crowne Social Desirability Scale were included in the survey, which was conducted face-to-face and using Audio Computer Self Administering Interview (ACASI) methods.ResultsThere were highly statistically significant differences in levels of social desirability response bias by levels of depressive symptoms, drug use stigma, physical health status, recent opiate and cocaine use, Alcohol Use Disorders Identification Test (AUDIT) scores, and size of social networks. There were no associations between health service utilization measures and social desirability bias. In multiple logistic regression models, even after including the Center for Epidemiologic Studies Depression Scale (CES-D) as a measure of depressive symptomology, social desirability bias was associated with recent drug use and drug user stigma. Social desirability bias was not associated with enrollment in prior research studies.ConclusionsThese findings suggest that social desirability bias is associated with key health measures and that the associations are not primarily due to depressive symptoms. Methods are needed to reduce social desirability bias. Such methods may include the wording and prefacing of questions, clearly defining the role of "study participant," and assessing and addressing motivations for socially desirable responses.



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Nurse-led counselling and replacement therapy is effective for smoking cessation in oral cancer patients

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Breast augmentation combined with a transposed glandular flap for prevention and correction of lower pole deformities

Abstract

Background

Lower pole deformities constitute the most complex problem encountered during and after breast augmentation. If the procedure is not accurately planned, the choice of techniques to correct lower pole deformity intraoperatively can be limited, leading to the possibility of additional scarring or the necessity of a second surgery.

Methods

Volume deficiencies of the lower pole after implant placement, such as flatness and double bubble, are indications for the proposed technique. A glandular flap is created by bisecting the lower pole of the gland and is transposed inwards and downwards to fill the deficient area. It is not necessary to fix the flap in place.

Results

Between January 2011 and December 2014, 30 patients underwent breast augmentation or augmentation-mastopexy combined with a transposed glandular flap. A desired lower pole was achieved in all the cases. No major complications were observed.

Conclusions

The transposed glandular flap herein described was proven to be useful to correct volume deficiencies of the lower pole after implant placement in cases of primary and secondary cases of breast augmentation.

Level of Evidence: Level IV, therapeutic study

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Inactivation of the KSRP gene modifies collagen antibody induced arthritis

Publication date: July 2017
Source:Molecular Immunology, Volume 87
Author(s): Rudolf Käfer, Katharina Schrick, Lisa Schmidtke, Evelyn Montermann, Dominika Hobernik, Matthias Bros, Ching-Yi Chen, Hartmut Kleinert, Andrea Pautz
The KH type splicing regulatory protein (KSRP) is a nucleic acid binding protein, which negatively regulates the stability and/or translatability of many mRNA species encoding immune-relevant proteins. As KSRP is expressed in immune cells including T and B cells, neutrophils, macrophages and dendritic cells, we wanted to analyze its importance for the development of autoimmune diseases.We chose collagen antibody-induced arthritis (CAIA) as an appropriate autoimmune disease mouse model in which neutrophils and macrophages constitute the main effector cell populations. We compared arthritis induction in wild type (WT) and KSRP^−/− mice and paws were taken for histological sections and qPCR analysis. Furthermore, we determined the frequencies of spleen immune cells by flow cytometry. Cytokine levels in spleen cell supernatants were determined by cytometric bead array analyses (CBA).After CAIA induction we unexpectedly observed in WT animals much stronger swelling of the paws than in KSRP^−/− mice. In accordance, histological staining of paw sections of KSRP^−/− animals revealed much lower frequencies of infiltrating immune cells in the joints compared to WT animals. Furthermore, CAIA-treatment resulted in reduced expression of several inflammatory factors (like CXCL-1, iNOS, TNF-α and S100A8) as well as immune cell marker genes (e.g. LFA-1, CD68, Ly6G) in the joints of KSRP^−/− mice.Spleen cells of KSRP^−/− mice showed lower frequencies of myeloid cells. On cytokine level IFN-γ production was increased in spleen cells of KSRP^−/− mice compared to WT samples.These data surprisingly suggest that the absence of KSRP protects against the induction of inflammatory arthritis.



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Mechanisms of Resistance to JAK2 Inhibitors in Myeloproliferative Neoplasms

Publication date: Available online 13 May 2017
Source:Hematology/Oncology Clinics of North America
Author(s): Sara C. Meyer

Teaser

Myeloproliferative neoplasms are driven by activated JAK2 signaling due to somatic mutations in JAK2, the thrombopoietin receptor MPL or the chaperone calreticulin in hematopoietic stem/progenitor cells. JAK2 inhibitors have been developed, but despite clinical benefits, they do not signficantly reduce the mutant clone. Loss of response to JAK2 inhibitors occurs and several mechanisms of resistance, genetic and functional, have been identified. Resistance mutations have not been reported in MPN patients suggesting incomplete target inhibition. Alternative targeting of JAK2 by HSP90 inhibitors or type II JAK2 inhibition overcomes resistance to current JAK2 inhibitors. Additional combined therapy approaches are currently being evaluated.


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Multi-Modal Classification of Neurodegenerative Disease by Progressive Graph-Based Transductive Learning

Publication date: Available online 13 May 2017
Source:Medical Image Analysis
Author(s): Zhengxia Wang, Xiaofeng Zhu, Ehsan Adeli, Yingying Zhu, Feiping Nie, Brent Munsell, Dinggang Shen, Guorong Wu
Graph-based transductive learning (GTL) is a powerful machine learning technique that is used when sufficient training data is not available. In particular, conventional GTL approaches first construct a fixed inter-subject relation graph that is based on similarities in voxel intensity values in the feature domain, which can then be used to propagate the known phenotype data (i.e., clinical scores and labels) from the training data to the testing data in the label domain. However, this type of graph is exclusively learned in the feature domain, and primarily due to outliers in the observed features, may not be optimal for label propagation in the label domain. To address this limitation, a progressive GTL (pGTL) method is proposed that gradually finds an intrinsic data representation that more accurately aligns imaging features with the phenotype data. In general, optimal feature-to-phenotype alignment is achieved using an iterative approach that: (1) refines inter-subject relationships observed in the feature domain by using the learned intrinsic data representation in the label domain, (2) updates the intrinsic data representation from the refined inter-subject relationships, and (3) verifies the intrinsic data representation on the training data to guarantee an optimal classification when applied to testing data. Additionally, the iterative approach is extended to multi-modal imaging data to further improve pGTL classification accuracy. Using Alzheimer's disease and Parkinson's disease study data, the classification accuracy of the proposed pGTL method is compared to several state-of-the-art classification methods, and the results show pGTL can more accurately identify subjects, even at different progression stages, in these two study data sets.

Graphical abstract

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Dual-core Steered Non-rigid Registration for Multi-modal Images via Bi-directional Image Synthesis

Publication date: Available online 13 May 2017
Source:Medical Image Analysis
Author(s): Xiaohuan Cao, Jianhua Yang, Yaozong Gao, Yanrong Guo, Guorong Wu, Dinggang Shen
In prostate cancer radiotherapy, computed tomography (CT) is widely used for dose planning purposes. However, because CT has low soft tissue contrast, it makes manual contouring difficult for major pelvic organs. In contrast, magnetic resonance imaging (MRI) provides high soft tissue contrast, which makes it ideal for accurate manual contouring. Therefore, the contouring accuracy on CT can be significantly improved if the contours in MRI can be mapped to CT domain by registering MRI with CT of the same subject, which would eventually lead to high treatment efficacy. In this paper, we propose a bi-directional image synthesis based approach for MRI-to-CT pelvic image registration. First, we use patch-wise random forest with auto-context model to learn the appearance mapping from CT to MRI domain, and then vice versa. Consequently, we can synthesize a pseudo-MRI whose anatomical structures are exactly same with CT but with MRI-like appearance, and a pseudo-CT as well. Then, our MRI-to-CT registration can be steered in a dual manner, by simultaneously estimating two deformation pathways: 1) one from the pseudo-CT to the actual CT and 2) another from actual MRI to the pseudo-MRI. Next, a dual-core deformation fusion framework is developed to iteratively and effectively combine these two registration pathways by using complementary information from both modalities. Experiments on a dataset with real pelvic CT and MRI have shown improved registration performance of the proposed method by comparing it to the conventional registration methods, thus indicating its high potential of translation to the routine radiation therapy.

Graphical abstract

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Ageing kinetics and strength of airborne-particle abraded 3Y-TZP ceramics

Publication date: Available online 12 May 2017
Source:Dental Materials
Author(s): Jasna Cotič, Peter Jevnikar, Andraž Kocjan
ObjectiveThe combined effects of alumina airborne-particle abrasion and prolonged in vitro ageing on the flexural strength of 3Y-TZP ceramic have been studied. The aim was to identify the different effects on the surface and subsurface regions that govern the performance of this popular bioceramic known for its susceptibility to low-temperature degradation (LTD).MethodsAs-sintered or airborne-particle abraded 3Y-TZP discs were subjected to ageing at 134°C for up to 480h. Biaxial flexural strength was measured and the relative amount of monoclinic phase determined using X-ray diffraction. The transformed zone depth (TZD) was observed on cross-sections with scanning electron microscopy coupled with a focused ion beam. Segmented linear regression was used to analyze the flexural strength and TZD as functions of the ageing time.ResultsA two-step linear ageing kinetics was detected in airborne-particle abraded specimens, reflecting the different microstructures through which the LTD proceeds into the bulk. A 10μm thick altered zone under the abraded surface was involved in both the surface strengthening and the increased ageing resistance. When the zone was annihilated by the LTD, the strength of the ceramic specimens and the speed of LTD returned to the values measured before abrasion. Even at prolonged ageing times, the strength of abraded groups was not lower than that of as-sintered groups.SignificanceBoth the ageing kinetics and the flexural strength were prominently affected by airborne-particle abrasion, which altered the subsurface microstructure and phase composition. Airborne-particle abrasion was not harmful to the 3Y-TZP ceramics' stability.

Graphical abstract

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PLGA nanoparticles as chlorhexidine-delivery carrier to resin-dentin adhesive interface

Publication date: Available online 12 May 2017
Source:Dental Materials
Author(s): Balasankar Meera Priyadarshini, Kakran Mitali, Thong Beng Lu, Harish K. Handral, Nileshkumar Dubey, Amr S. Fawzy
ObjectiveTo characterize and deliver fabricated CHX-loaded PLGA-nanoparticles inside micron-sized dentinal-tubules of demineralized dentin-substrates and resin-dentin interface.MethodsNanoparticles fabricated by emulsion evaporation were assessed in-vitro by different techniques. Delivery of drug-loaded nanoparticles to demineralized dentin substrates, interaction with collagen matrix, and ex-vivo CHX-release profiles using extracted teeth connected to experimental setup simulating pulpal hydrostatic pressure were investigated. Furthermore, nanoparticles association/interaction with a commercial dentin-adhesive applied to demineralized dentin substrates were examined.ResultsThe results showed that the formulated nanoparticles demonstrated attractive physicochemical properties, low cytotoxicity, potent antibacterial efficacy, and slow degradation and gradual CHX release profiles. Nanoparticles delivered efficiently inside dentinal-tubules structure to sufficient depth (>10μm) against the simulated upward pulpal hydrostatic-pressure, even after bonding-resins infiltration and were attached/retained on collagen-fibrils. These results verified the potential significance of this newly introduced drug-delivery therapeutic strategy for future clinical applications and promote for a new era of future dental research.SignificanceThis innovative drug-delivery strategy has proven to be a reliable method for delivering treatments that could be elaborated for other clinical applications in adhesive and restorative dentistry.

Graphical abstract

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Psychiatric Patient Length of Stay in the Emergency Department Following Closure of a Public Psychiatric Hospital

Publication date: Available online 13 May 2017
Source:The Journal of Emergency Medicine
Author(s): Ryan K. Misek, Ashley D. Magda, Samantha Margaritis, Robert Long, Erik Frost
BackgroundPsychiatric patient boarding in the emergency department (ED) is a ubiquitous problem associated with increased morbidity and mortality.ObjectiveWe evaluate the effect of closing a public psychiatric facility in a major metropolitan area on the ED length of stay (LOS) of psychiatric patients.MethodsThis was a retrospective chart review at two metropolitan EDs of all patients assessed to require inpatient psychiatric hospitalization. The time of arrival, time of disposition, time of transfer, insurance status, and accepting facility type were collected prior to and following the closure of a local inpatient psychiatric facility.ResultsWe analyzed a total of 1107 patients requiring inpatient psychiatric hospitalization, with 671 patients who presented prior to the closure of the closest public psychiatric facility and 436 patients that presented following the facility closure. Following hospital closure, patients with private insurance (620 min before, 771 min after) and Medicare/Medicaid (642 min before, 718 min after) had statistically significantly longer ED LOS, as well as patients transferred to a private psychiatric hospital (664 min prior, 745 min after). However, overall ED length of stay following hospital closure for transfer of all psychiatric patients requiring inpatient hospitalization was not found to be statistically significant (1017 min prior, 967 min after).ConclusionThere was a statistically significant increase in ED LOS for patients with private insurance, Medicare/Medicaid, and for those patients transferred to a private psychiatric facility following closure of a public mental health hospital; however, overall, ED LOS was not increased for patients transferred to an inpatient psychiatric facility. This study highlights the significant impact that the closure of a single inpatient psychiatric facility can have on nearby EDs. We hope to bring attention to the need for increased psychiatric services during a time when there is a nationwide trend toward the reduction of available inpatient psychiatric beds.



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An Unusual Case of Flank Pain: More Than Just an Inguinal Hernia

Publication date: Available online 13 May 2017
Source:The Journal of Emergency Medicine
Author(s): Kareem S. Elsayed, Raymond J. Melder, Michael C. Nguyen




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Numtogenesis as a Mechanism for Development of Cancer

Publication date: Available online 13 May 2017
Source:Seminars in Cancer Biology
Author(s): Keshav K. Singh, Aaheli Roy Choudhury, Hemant K. Tiwari
Transfer of genetic material from cytoplasmic organelles to the nucleus, an ongoing process, has implications in evolution, aging, and human pathologies such as cancer. The transferred mitochondrial DNA (mtDNA) fragments in the nuclear genome are called nuclear mtDNA or NUMTs. We have named the process numtogenesis, defining the term as the transfer of mtDNA into the nuclear genome, or, less specifically, the transfer of mitochondria or mitochondrial components into the nucleus. There is increasing evidence of the involvement of NUMTs in human biology and pathology. Although information pertaining to NUMTs and numtogenesis is sparse, the role of this aspect of mitochondrial biology to human cancers is apparent. In this review, we present available knowledge about the origin and mechanisms of numtogenesis, with special emphasis on the role of NUMTs in human malignancies. We describe studies undertaken in our laboratory and in others and discuss the influence of NUMTs in tumor initiation and progression and in survival of cancer patients. We describe suppressors of numtogenesis and evolutionary conserved mechanisms underlying numtogenesis in cancer. An understanding the emerging field of numtogenesis should allow comprehension of this process in various malignancies and other diseases and, more generally, in human health.



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Antioxidant polyphenols in cancer treatment: friend, foe or foil?

Publication date: Available online 13 May 2017
Source:Seminars in Cancer Biology
Author(s): Gian Luigi Russo, Idolo Tedesco, Carmela Spagnuolo, Maria Russo
Cancer prevention can be probably obtained with easier, faster and less financial strains by pursuing educational programs aimed to induce changes in lifestyle, starting from dietary habits. In the past decades, observational and case-control studies tried to establish a functional relationship between cancer mortality and morbidity and diet. The field becomes even more intricate when scientists investigated which dietary components are responsible for the putative, protective effects of fruits and vegetables against cancer. A relevant part of the literature focused on the positive role of "antioxidant" compounds in foods, including polyphenols. The present review critically evaluate clinical and pre-clinical studies based on polyphenol administration, which contributed to support the concept, deeply rooted in the general population, that antioxidant polyphenols can fight cancer. The controversial and contradictory issues related to the pros and cons on the use of polyphenols against cancer reflect the confounding assumption that cancer treatment and cancer prevention may overlap. We conclude that a clear cut must be done between these two concepts and that the experimental approaches to investigate one or the other should be significantly different, starting from adequate and specifically selected cellular models.



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Supervised or unsupervised rehabilitation after total hip replacement provides similar improvements for patients: a randomised controlled trial

Publication date: Available online 12 May 2017
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Corinne Coulter, Diana M. Perriman, Teresa M. Neeman, Paul N. Smith, Jennifer M. Scarvell
ObjectiveTo determine do patients do better with unsupervised home PT or in an outpatient setting Are the outcomes after a supervised (centre-based) and an independent (home-based) physical rehabilitation program delivered in the early post-discharge phase (<8weeks) equivalent in an adult THR population.SettingAcute care public hospital in the region, supporting a population of almost 540,000.DesignSingle blinded randomised controlled trial.ParticipantsAdult patients (n=98) after unilateral elective total hip replacement (THR) were randomly assigned to supervised/centre-based exercise (n=56) or unsupervised/home exercise (n=42) and followed 6 months post-surgery.InterventionThe supervised group attended a 4 week outpatient rehabilitation program supervised by a physiotherapist. The unsupervised group was given written and pictorial instructions to perform rehabilitation independently at home.Outcome measuresThe WOMAC, SF-36 mental and physical component scores(MCS and PCS) questionnaires, the UCLA activity rating and the Timed up and Go test (TUG).ResultsThere were no differences between groups for any measure. Overall differences between the adjusted means were: WOMAC 0.5 [-6.75, 5.73], SF-36 PCS 0.8 [-6.5 - 8.1], SF-36 MCS 1.7 [-4.1 - 7.4], UCLA 0.3 [5.19, 6.10] and TUG 0 secs [-1.4 - 1.3].ConclusionResults demonstrated that outcomes in response to rehabilitation after THR are clinically and statistically similar whether the program was supervised or not. The results suggest that early rehabilitation programs can be effectively delivered unsupervised in the home to low-risk patients discharged home after THR. However, the relative effect of late stage rehabilitation was not tested.



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Mindfulness is Associated with Treatment Response from Non-Pharmacological Exercise Interventions in Knee Osteoarthritis

Publication date: Available online 12 May 2017
Source:Archives of Physical Medicine and Rehabilitation
Author(s): Augustine C. Lee, William F. Harvey, Lori Lyn Price, Xingyi Han, Jeffrey B. Driban, John B. Wong, Mei Chung, Timothy E. McAlindon, Chenchen Wang
ObjectiveTo examine the association between baseline mindfulness and response from exercise interventions in knee osteoarthritis (OA).DesignCohort Study; Responder analysis of a clinical trial subsetSettingUrban tertiary care academic hospitalParticipants86 participants with symptomatic, radiographic knee OA (mean age, 60 years; 74% female; 48% white)Interventions12 weeks (twice per week) of Tai Chi or Physical Therapy exerciseMain Outcome Measure(s)Treatment response was defined using Osteoarthritis Research Society International criteria indicating meaningful improvements in the Western Ontario and McMaster Osteoarthritis Index (WOMAC) pain, function, or Patient Global Assessment scores. At baseline, participants completed the Five Facet Mindfulness Questionnaire (FFMQ; mean total score ±SD: 142±17) and were grouped into three categories of total mindfulness: higher, medium, or lower. Relative risk (RR) ratios were used to compare treatment response across groups.ResultsParticipants with higher total mindfulness appeared to be 38% (95% CI: 1.05, 1.83) more likely to meet responder criteria than those with lower mindfulness. We found no significant difference between medium and lower mindfulness groups (RR=1.0; 95% CI: 0.69, 1.44). Among the 5 mindfulness facets, medium Acting-with–Awareness was 46% (95% CI: 1.09, 1.96) more likely to respond than lower Acting-with–Awareness, and higher Acting-with–Awareness was 34% more likely to respond, but this did not reach significance (95% CI: 0.97, 1.86).ConclusionsIn this study, higher mindfulness, primarily driven by its Acting-with-Awareness facet, was significantly associated with a greater likelihood of response to non-pharmacological exercise interventions in knee OA. This suggests that mindfulness-cultivating interventions may increase the likelihood of response from exercise.



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High resolution T2 MRI in the diagnosis of cerebellopontine angle and internal auditory canal lesions

Publication date: Available online 13 May 2017
Source:Clinical Imaging
Author(s): Jonathan T. Maslan, Christopher M. Lack, Michael Zapadka, Tyler G. Gasser, Eric Oliver
High resolution T2 magnetic resonance imaging (MRI) can provide exquisite detail of internal auditory canal (IAC) and cerebellopontine angle (CPA) lesions. In this retrospective case series, blinded imaging sequences were delivered to three radiologists and compared with previously archived clinical reads that were non-blinded and incorporated both T1+C and T2 sequences together. This article demonstrates high sensitivity and specificity for high resolution T2 MRI particularly with lesions >5mm. This suggests a role for high resolution T2 MRI as an initial screening sequence or as a surveillance sequence.



http://ift.tt/2rcgUxf

Possible involvement of the lipoxygenase and leukotriene signaling pathways in cisplatin-mediated renal toxicity

Abstract

Purpose

The present study examined the possible involvement of the lipoxygenase (LOX) pathway in cisplatin (CPT)-induced nephrotoxicity.

Methods

Wistar albino rats were challenged with CPT IP injection (7.5 mg/kg) and were sacrificed after one week. Signs of renal dysfunction, including urea and creatinine clearance levels and renal histological structure, were investigated. Gene and protein expression levels of different LOX pathway enzymes and products, including 5-LOX, 12-LOX, 15-LOX, 5-LOX activating protein (FLAP), leukotriene A4 hydrolase (LTA4 hydrolase), leukotriene C4 synthase (LTC4 synthase), LTB4 receptor, and cysteinyl (cys) LT receptor types 1 and 2, were also determined in the kidneys using real-time PCR and western blotting, respectively. The serum and kidney levels of LTB4 and inflammatory markers were also estimated.

Results

CPT renal toxicity was established as the creatinine and urea clearance levels were significantly reduced, while the serum levels of creatinine and urea were markedly increased. We reported a considerable up-regulation in the mRNA and protein expression levels of 5-LOX, FLAP, 12-LOX, LTA4 hydrolase, LTC4 synthase, LTB4 receptor, and Cys LT receptor types 1 and 2, while 15-LOX expression did not significantly change in the CPT group. Additionally, LTB4 and inflammatory indicators in serum and renal levels were elevated significantly in the CPT group. Histopathological examination clearly showed the nephrotoxic changes in the renal tissues of CPT-challenged animals.

Conclusions

Our findings suggested, for the first time, the participation of LOX enzymes and products in the signaling pathway leading to CPT-associated nephrotoxicity, which could be the foundation stone for combining LOX pathway attenuators with CPT therapy to decrease CPT-associated renal toxicity.

http://ift.tt/2qgu7pv

UGT1A1 polymorphisms with irinotecan-induced toxicities and treatment outcome in Asians with Lung Cancer: a meta-analysis

Abstract

Previous studies of irinotecan pharmacogenetics have shown that the UGT1A1*28 polymorphism has an effect on irinotecan (IRI)-induced toxicities in Caucasians. Yet compared with the UGT1A1*6 mutation, the UGT1A1*28 occurs at a much lower frequency in the Asians. Whether UGT1A1*6 and UGT1A1*28 are associated with IRI-induced neutropenia, diarrhea and IRI-based chemotherapy tumor response (TR) in Asians with lung cancer remains controversial. In this meta-analysis, we found a higher risk of neutropenia and diarrhea with IRI-based chemotherapy in Asians with lung cancer carrying the UGT1A1*6 polymorphism. However, UGT1A1*28 showed a weak correlation with diarrhea, but no significant correlation with neutropenia. Neither UGT1A1*6 nor UGT1A1*28 is associated with IRI-based chemotherapy TR. These data suggest that the UGT1A1*28 polymorphism may not be a suitable biomarker to predict IRI-induced toxicities and chemotherapy TR in Asians, while UGT1A*6 polymorphism is associated with a higher risk of IRI-induced neutropenia and diarrhea, but not IRI-based chemotherapy TR.

http://ift.tt/2pvSXF5

Characterization of rainwater chemical composition after a Southeast Asia haze event: insight of transboundary pollutant transport during the northeast monsoon

Abstract

Open biomass burning in Peninsula Malaysia, Sumatra, and parts of the Indochinese region is a major source of transboundary haze pollution in the Southeast Asia. To study the influence of haze on rainwater chemistry, a short-term investigation was carried out during the occurrence of a severe haze episode from March to April 2014. Rainwater samples were collected after a prolonged drought and analyzed for heavy metals and major ion concentrations using inductively coupled plasma mass spectroscopy (ICP-MS) and ion chromatography (IC), respectively. The chemical composition and morphology of the solid particulates suspended in rainwater were examined using a scanning electron microscope coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). The dataset was further interpreted using enrichment factors (EF), statistical analysis, and a back trajectory (BT) model to find the possible sources of the particulates and pollutants. The results show a drop in rainwater pH from near neutral (pH 6.54) to acidic (<pH 4.00) during the haze to non-haze transitional period, suggesting that the deposition rate of sulfate and nitrate in the atmosphere via the precipitation process was relatively lower compared to the mineral components. Zinc, nitrate, and calcium, which were the predominant elements in the first rainwater samples. Besides, the results of the SEM-EDS indicated that the zinc was possibly originated from anthropogenic activities which are consistent with the results obtained from EF. The BT model showed that pollutants transported from the mainland of Indo-China and the marine region in the South China Sea were responsible for the high pollution event in the study area. These findings can be useful in identifying contributions of pollutants from single or multiple sources in rainwater samples during haze episodes.

http://ift.tt/2pIVd7a

Evaluation of various solvent systems for lipid extraction from wet microalgal biomass and its effects on primary metabolites of lipid-extracted biomass

Abstract

Microalgae have tremendous potential to grow rapidly, synthesize, and accumulate lipids, proteins, and carbohydrates. The effects of solvent extraction of lipids on other metabolites such as proteins and carbohydrates in lipid-extracted algal (LEA) biomass are crucial aspects of algal biorefinery approach. An effective and economically feasible algae-based oil industry will depend on the selection of suitable solvent/s for lipid extraction, which has minimal effect on metabolites in lipid-extracted algae. In current study, six solvent systems were employed to extract lipids from dry and wet biomass of Scenedesmus obliquus. To explore the biorefinery concept, dichloromethane/methanol (2:1 v/v) was a suitable solvent for dry biomass; it gave 18.75% lipids (dry cell weight) in whole algal biomass, 32.79% proteins, and 24.73% carbohydrates in LEA biomass. In the case of wet biomass, in order to exploit all three metabolites, isopropanol/hexane (2:1 v/v) is an appropriate solvent system which gave 7.8% lipids (dry cell weight) in whole algal biomass, 20.97% proteins, and 22.87% carbohydrates in LEA biomass.

Graphical abstract:

Lipid extraction from wet microalgal biomass and biorefianry approach

http://ift.tt/2qe7cgr

Adsorption of terpenic compounds onto organo-palygorskite

Abstract

Essential oils from aromatic plants are currently mentioned as suitable tools for excellent protection of stored grains from insect pest attacks. The present work aimed to study the processes of the synthesis insecticidal formulation with clay. The active terpenic compounds of essential oil of Eucalyptus globulus (Eg) were fixed in the palygorskite by adsorption process. Two sample types of palygorskites were used: raw and organo-palygorskite. The palygorskite clays were characterized by different physicochemical techniques including X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, thermogravimetric analysis (TG), differential thermal analysis (DTA), Brunauer-Emmet-Teller (BET), and scanning electron microscope (SEM). Results reveal that the raw clay has a fibrous structure with impurities essential calcite. These structures and physicochemical properties of raw palygorskite and organo-palygorskite give it the potential of material adsorbent. Results show that the adsorption capacity strongly depends on affinity between terpenic compounds and organic cations rather than on interlayer distance of organo-palygorskite. The highest adsorption capacity of terpenic compounds is acquired with palygorskite interlaced by didodecyldimethylammonium bromide (DDDMA). These results validated the potential utility of the Paly-DDDMA as adsorbent fibrous clay for the retention of terpenic compounds in application of environmental preservation.

http://ift.tt/2qemQID

Decontamination of arsenic(V)-contained liquid phase utilizing Fe 3 O 4 /bone char nanocomposite encapsulated in chitosan biopolymer

Abstract

The application of a novel nanocomposite synthesized through the combination of Fe₃O₄ nanoparticles and bone char particles for the adsorption of As(V) ions in the aquatic medium was investigated. As-prepared nanocomposite was immobilized by using chitosan biopolymer. The characterization of the nanocomposite was performed via SEM, XRD, FT-IR, and BET together with the determination of zero-point charge of the adsorbent surface. As results, the obtained experimental data were fitted well with pseudo-first-order kinetic model (R² = 0.997) and Langmuir isotherm model (R² = 0.990) with the maximum adsorption capacity of about 112 μg/g. Increasing the dosage of nanocomposite and initial solute concentration led to increasing the adsorption capacity of As(V) ions, while decreasing the solution temperature resulted in the enhanced adsorption process. According to the results of thermodynamic study, the adsorption of As(V) ions onto the nanocomposite was spontaneous and exothermic in nature.

http://ift.tt/2pJ6Iv1

Evaluation of carbofuran-mediated toxicity against human lymphocytes and red blood cells in simulated wastewater degraded by coagulation–flocculation

Abstract

Coagulation–flocculation in water treatment has been relied upon aluminum (Al) and iron (Fe) salts for treatment of contaminants present in source waters containing dissolved organic compounds. However, water quality deteriorates day by day which makes it urgent to improve the standards of the treatment procedure. Coagulation–flocculation–sedimentation performance of ferric chloride and alum was comparatively investigated for carbofuran treatment in simulated wastewater. Coagulation trails were performed in a jar test at several pH levels and coagulant doses to determine reduction efficiencies of carbofuran degradation and chemical oxygen demand (COD). Effect of carbofuran on proliferation, viability, and direct cytotoxicity was performed using human neuroblastoma cells U-87. Direct toxicity of carbofuran on human mononuclear cells and red blood cells (RBC) was also analyzed. Carbofuran and its derivatives were found to be relatively safe at low concentration (2–5 μM). However, at slightly higher concentration (8 μM), a moderate loss in viability and proliferative potential was observed. Taken together, these results suggest that carbofuran appears to be safe at moderate or low concentration with respect to viability of normal human lymphocytes and RBC.

http://ift.tt/2qefB3h

Biogeochemical controls on mercury methylation in the Allequash Creek wetland

Abstract

We measured mercury methylation potentials and a suite of related biogeochemical parameters in sediment cores and porewater from two geochemically distinct sites in the Allequash Creek wetland, northern Wisconsin, USA. We found a high degree of spatial variability in the methylation rate potentials but no significant differences between the two sites. We identified the primary geochemical factors controlling net methylmercury production at this site to be acid-volatile sulfide, dissolved organic carbon, total dissolved iron, and porewater iron(II). Season and demethylation rates also appear to regulate net methylmercury production. Our equilibrium speciation modeling demonstrated that sulfide likely regulated methylation rates by controlling the speciation of inorganic mercury and therefore its bioavailability to methylating bacteria. We found that no individual geochemical parameter could explain a significant amount of the observed variability in mercury methylation rates, but we found significant multivariate relationships, supporting the widely held understanding that net methylmercury production is balance of several simultaneously occurring processes.

http://ift.tt/2pJ8v3v

The effects of cadmium pulse dosing on physiological traits and growth of the submerged macrophyte Vallisneria spinulosa and phytoplankton biomass: a mesocosm study

Abstract

Pulse inputs of heavy metals are expected to increase with a higher frequency of extreme climate events (heavy rain), leading to stronger erosion of contaminated and fertilized farmland soils to freshwaters, with potentially adverse effects on lake ecosystems. We conducted a 5-month mesocosm study to elucidate the responses of the submerged macrophyte Vallisneria spinulosa and phytoplankton to four different doses of cadmium (Cd): 0 (control), 0.05, 0.5, and 5 g m⁻² (CK, I, II, and III, respectively) under mesotrophic conditions. We found that total phosphorus concentrations were larger in the three Cd pulse treatments, whereas total nitrogen concentrations did not differ among the four treatments. The contents of chlorophyll a and soluble sugar in macrophyte leaves decreased in III, and total biomass, ramet number, plant height, and total stolon length of macrophytes were lower in both II and III. In contrast, abundances of the three main phytoplankton taxa—Cyanophyta, Chlorophyta, and Bacillariophyta—did not differ among treatments. Total phytoplankton biomass was, however, marginally lower in CK than in the Cd treatments. We conclude that exposure to strong Cd pulses led to significantly reduced growth of macrophytes, while no obvious effect appeared for phytoplankton.

http://ift.tt/2qehVrf

Adsorption affinity and selectivity of 3-ureidopropyltriethoxysilane grafted oil palm empty fruit bunches towards mercury ions

Abstract

This study was conducted to investigate the potential application of oil palm empty fruit branches (OPEFB) as adsorbents to remove organic methylmercurry, MeHg(II), and inorganic Hg(II) from aqueous solution. The OPEFB was functionalized with amine containing ligand namely 3-ureidopropyltriethoxysilane (UPTES) aiming for better adsorption performance towards both mercury ions. The adsorption was found to be dependent on initial pH, initial concentraton, temperatures, and contact time. The maximum adsorption capacities (Q_m.exp) of Hg(II) adsorption onto OPEFB and UPTES-OPEFB were 0.226 and 0.773 mmol/g, respectively. The Q_m.exp of MeHg(II) onto OPEFB, however, was higher than UPTES-OPEFB. The adsorption kinetic data obeyed the Elovich model and the adsorption was controlled by the film-diffusion step. The calculated thermodynamic parameters indicate an endothermic adsorption process. Adsorption data analysis indicates that the adsorption mechanism may include ion-exchange, complexation, and physisorption interactions. The potential applications of adsorbents were demonstrated using oilfield produced water and natural gas condensate. The UPTES-OPEFB offered higher selectivity towards both mercury ions than OPEFB. The regenerability studies indicated that the adsorbent could be reused for multiple cycles.

http://ift.tt/2pIYN15

Reclamation of heavy metals from contaminated soil using organic acid liquid generated from food waste: removal of Cd, Cu, and Zn, and soil fertility improvement

Abstract

Food waste fermentation generates complicated organic and acidic liquids with low pH. In this work, it was found that an organic acid liquid with pH 3.28 and volatile low-molecular-weight organic acid (VLMWOA) content of 5.2 g/L could be produced from food wastes after 9-day fermentation. When the liquid-to-solid ratio was 50:1, temperature was 40 °C, and contact time was 0.5–1 day, 92.9, 78.8, and 52.2% of the Cd, Cu, and Zn in the contaminated soil could be washed out using the fermented food waste liquid, respectively. The water-soluble, acid-soluble, and partly reducible heavy metal fractions can be removed after 0.5-day contact time, which was more effective than that using commercially available VLMWOAs (29–72% removal), as the former contained microorganisms and adequate amounts of nutrients (nitrogen, phosphorous, and exchangeable Na, K, and Ca) which favored the washing process of heavy metals. It is thus suggested that the organic acid fractions from food waste has a considerable potential for reclaiming contaminated soil while improving soil fertility.

http://ift.tt/2qefzIH

Adapting the Vegetative Vigour Terrestrial Plant Test for assessing ecotoxicity of aerosol samples

Abstract

Plants, being recognized to show high sensitivity to air pollution, have been long used to assess the ecological effects of airborne contaminants. However, many changes in vegetation are now generally attributed to atmospheric deposition of aerosol particles; the dose–effect relationships of this process are usually poorly known. In contrast to bioindication studies, ecotoxicological tests (or bioassays) are controlled and reproducible where ecological responses are determined quantitatively. In our study, the No. 227 OECD Guideline for the Testing of Chemicals: Terrestrial Plant Test: Vegetative Vigour Test (hereinafter referred to as 'Guideline') was adapted and its applicability for assessing the ecotoxicity of water-soluble aerosol compounds of aerosol samples was evaluated. In the aqueous extract of the sample, concentration of metals, benzenes, aliphatic hydrocarbons and PAHs was determined analytically. Cucumis sativus L. plants were sprayed with the aqueous extract of urban aerosol samples collected in a winter sampling campaign in Budapest. After the termination of the test, on day 22, the following endpoints were measured: fresh weight, shoot length and visible symptoms. The higher concentrations applied caused leaf necrosis due to toxic compounds found in the extract. On the other hand, the extract elucidated stimulatory effect at low concentration on both fresh weight and shoot length. The test protocol, based on the Guideline, seems sensitive enough to assess the phytotoxicity of aqueous extract of aerosol and to establish clear cause–effect relationship.

http://ift.tt/2pIVas0

Cadmium impact, accumulation and detection in poplar callus cells

Abstract

Effect of cadmium cations and their interaction with silicon cations was determined in poplar calli and expressed as changes in callus growth, cell viability and cadmium cation accumulation. Cell viability throughout culture versus cadmium cation accumulation in cells is discussed. At the same time, the study sought appropriate methods for cadmium cation detection in callus cells and also in experiments with low plant material (e.g. protoplasts). Cadmium cations were determined by atomic absorption spectroscopy and using fluorescence microscopy with a specific cadmium cation fluorescent dye. The detection of cadmium cations in callus cells by the latter method appears suitable because the callus cells are surrounded by primary cell walls without auto-fluorescence and these values fit well with atomic absorption spectroscopy quantification. However, the visualisation method has some limits discussed below.

http://ift.tt/2qe6teX

Variation of microbial communities and functional genes during the biofilm formation in raw water distribution systems and associated effects on the transformation of nitrogen pollutants

Abstract

This study aimed to investigate the variation of microbial communities and functional genes during the biofilm formation in raw water distribution systems without prechlorination and associated effects on the transformation of nitrogen pollutants by using a designed model pipe system. The results showed the transformation of nitrogen pollutants was obvious during the biofilm formation. The richness and diversity of the microbial communities changed significantly. The higher abundance of Nitrospirae in biofilm samples significantly contributed to biological nitrification. In particular, the stable content of Bacteroidetes in the biofilm and soluble microbial products released by the biomass might have enhanced the increase in dissolved organic nitrogen. In addition, the variation tendency of nitrogen functional gene abundances and their strong effects on NH₄⁺-N, NO₂⁻-N, and NO₃⁻-N transformation were clearly observed. These findings provide new insights into the evolution of microbial communities and functional genes during the initial operation period of real-world raw water distribution pipes and highlight management and possible safety issues in the subsequent water treatment process.

http://ift.tt/2qeeCQV

Effect of industrial and domestic ash from biomass combustion, and spent coffee grounds, on soil fertility and plant growth: experiments at field conditions

Abstract

An experimental study was conducted at field conditions in order to evaluate the effect of application of ash from biomass combustion on some soil fertility characteristics and plant growth. Application of 7.5 Mg ha⁻¹ industrial fly ash (IA), domestic ash (DA), and a 50:50 mix of domestic ash (DA) and spent coffee grounds (SCG) was made in different soil parcels. Lolium perenne seeds were sown and the grown biomass was harvested and quantified after 60 days. Soil samples from each parcel were also collected after that period and characterized. Both soil and grown biomass samples were analyzed for Ca, Mg, Na, K, P, Fe, Mn, Zn, and Al contents. Soil pH was determined before and after amendment. All applications rose significantly soil pH. Domestic ash, whether combined with coffee grounds or not, proved to be efficient at supplying available macronutrients Ca, Mg, K, and P to the soil and also reducing availability of Al (more than industrial ash). However, it inhibited plant growth, even more when combined with spent coffee grounds. As regards to elemental abundance in plant tissue, both domestic ash treatments reduced Ca and enhanced Al contents, unlike industrial ash, which proved less harmful for the load applied in the soil. Hence, it was possible to conclude that application load should be a limiting factor for this management option for the studied materials.

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Neuro-Cardiac-Guided TMS (NCG-TMS): Probing DLPFC-sgACC-vagus nerve connectivity using heart rate – First results

Publication date: Available online 12 May 2017
Source:Brain Stimulation
Author(s): Tabitha A. Iseger, Frank Padberg, J. Leon Kenemans, Richard Gevirtz, Martijn Arns
BackgroundGiven that many studies suggest a role of DLPFC-sgACC connectivity in depression and prior research demonstrating that neuromodulation of either of these nodes modulates parasympathetic activity and results in a heart rate deceleration, a new method is proposed to individualize localization of the DLPFC. This can, among others, be useful for rTMS treatment of depression.MethodsTen healthy subjects received three trains of 10Hz rTMS randomly over 7 target regions (10-20 system).ResultsOverall, F3 and F4 expressed the largest heart rate deceleration, in line with studies suggesting these are the best 10-20 sites to target the DLPFC. On the individual level, 20-40% subjects expressed the largest heart rate deceleration at FC3 or FC4, indicating individual differences as to the 'optimal site for stimulation'.ConclusionsThese results show that the NCG-TMS method is valid to localize the entry into the DLPFC-sgACC network.



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Advanced Correlation Grid: Analysis and Visualisation of Functional Connectivity among Multiple Spike Trains

Publication date: Available online 12 May 2017
Source:Journal of Neuroscience Methods
Author(s): Mohammad Shahed Masud, Roman Borisyuk, Liz Stuart
BackgroundThis study analyses multiple spike trains (MST) data, defines its functional connectivity and subsequently visualises an accurate diagram of connections. This is a challenging problem. For example, it is difficult to distinguish the common input and the direct functional connection of two spike trains.New methodThe new method presented in this paper is based on the traditional pairwise cross-correlation function (CCF) and a new combination of statistical techniques. First, the CCF is used to create the Advanced Correlation Grid (ACG) correlation where both the significant peak of the CCF and the corresponding time delay are used for detailed analysis of connectivity. Second, these two features of functional connectivity are used to classify connections. Finally, the visualization technique is used to represent the topology of functional connections.ResultsExamplesare presented in the paper to demonstrate the new Advanced Correlation Grid method and to show how it enables discrimination between (i) influence from one spike train to another through an intermediate spike train and (ii) influence from one common spike train to another pair of analysed spike trains.Comparison with existing methodsThe ACG method enables scientists to automatically distinguish between direct connections from spurious connections such as common source connection and indirect connection whereas existing methods require in-depth analysis to identify such connections.ConclusionsThe ACG is a new and effective method for studying functional connectivity of multiple spike trains. This method can identify accurately all the direct connections and can distinguish common source and indirect connections automatically.



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A new platform for long-term tracking and recording of neural activity and simultaneous optogenetic control in freely behaving Caenorhabditis elegans

Publication date: Available online 12 May 2017
Source:Journal of Neuroscience Methods
Author(s): Keiko Gengyo-Ando, Yuko Kagawa-Nagamura, Masamichi Ohkura, Xianfeng Fei, Min Chen, Koichi Hashimoto, Junichi Nakai
BackgroundReal-time recording and manipulation of neural activity in freely behaving animals can greatly advance our understanding of how neural circuits regulate behavior. Ca²⁺ imaging and optogenetic manipulation with optical probes are key technologies for this purpose. However, integrating the two optical approaches with behavioral analysis has been technically challenging.New methodHere, we developed a new imaging system, ICaST (Integrated platform for Ca²⁺ imaging, Stimulation, and Tracking), which combines an automatic worm tracking system and a fast-scanning laser confocal microscope, to image neurons of interest in freely behaving C. elegans. We optimized different excitation wavelengths for the concurrent use of channelrhodopsin-2 and G-CaMP, a green fluorescent protein (GFP)-based, genetically encoded Ca²⁺ indicator.ResultsUsing ICaST in conjunction with an improved G-CaMP7, we successfully achieved long-term tracking and Ca²⁺ imaging of the AVA backward command interneurons while tracking the head of a moving animal. We also performed all-optical manipulation and simultaneous recording of Ca²⁺ dynamics from these same GABAergic motor neurons in conjunction with behavior monitoring and manipulation.Comparison with existing method(s)Our system differs from conventional systems in that it does not require fluorescent markers for tracking and can track any part of the worm's body via bright-field imaging at high magnification. Consequently, this approach enables the long-term imaging of activity from neurons or nerve processes of interest with high spatiotemporal resolution.ConclusionOur imaging system is a powerful tool for studying the neural circuit mechanisms of C. elegans behavior and has potential for use in other small animals.



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Reduced dopamine receptors and transporters but not synthesis capacity in normal aging adults: a meta-analysis

Publication date: Available online 12 May 2017
Source:Neurobiology of Aging
Author(s): Teresa M. Karrer, Anika K. Josef, Rui Mata, Evan D. Morris, Gregory R. Samanez-Larkin
Many theories of cognitive aging are based on evidence that dopamine (DA) declines with age. Here we performed a systematic meta-analysis of cross-sectional PET and SPECT studies on the average effects of age on distinct DA targets (receptors, transporters, or relevant enzymes) in healthy adults (N=95 studies including 2,611 subjects). Results revealed significant moderate to large, negative effects of age on DA transporters and receptors. Age had a significantly larger effect on D1- than D2-like receptors. In contrast, there was no significant effect of age on DA synthesis capacity. The average age reductions across the DA system were 3.7–14.0% per decade. A meta-regression found only DA target as a significant moderator of the age effect. This study precisely quantifies prior claims of reduced DA functionality with age. It also identifies presynaptic mechanisms (spared synthesis capacity and reduced DA transporters) that may partially account for previously unexplained phenomena whereby older adults appear to use dopaminergic resources effectively. Recommendations for future studies including minimum required samples sizes are provided.



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Sleep in the northern fur seal

Publication date: June 2017
Source:Current Opinion in Neurobiology, Volume 44
Author(s): Oleg I Lyamin, Lev M Mukhametov, Jerome M Siegel
The pattern of sleep in the fur seal, a semiaquatic pinniped, has several striking behavioral and physiological adaptations that allow this species to inhabit both the land and water environment. These features include unihemispheric slow wave sleep (USWS, also being unihemispheric waking), the ability to maintain movement for stabilization of the sleep posture and to briefly open one eye while having a sleep electroencephalogram (EEG) in one hemisphere. In vivo microdialysis studies suggest that acetylcholine release is required for cortical activation during USWS, and that monoamines are not required for USWS. The need to breathe, to maintain efficient thermoregulation, and to avoid predation have shaped the sleep patterns in semiaquatic fur seals as in fully aquatic cetaceans.



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Emotional arousal impairs association-memory: Roles of amygdala and hippocampus

Publication date: 1 August 2017
Source:NeuroImage, Volume 156
Author(s): Christopher R. Madan, Esther Fujiwara, Jeremy B. Caplan, Tobias Sommer
Emotional arousal is well-known to enhance memory for individual items or events, whereas it can impair association memory. The neural mechanism of this association memory impairment by emotion is not known: In response to emotionally arousing information, amygdala activity may interfere with hippocampal associative encoding (e.g., via prefrontal cortex). Alternatively, emotional information may be harder to unitize, resulting in reduced availability of extra-hippocampal medial temporal lobe support for emotional than neutral associations. To test these opposing hypotheses, we compared neural processes underlying successful and unsuccessful encoding of emotional and neutral associations. Participants intentionally studied pairs of neutral and negative pictures (Experiments 1–3). We found reduced association-memory for negative pictures in all experiments, accompanied by item-memory increases in Experiment 2. High-resolution fMRI (Experiment 3) indicated that reductions in associative encoding of emotional information are localizable to an area in ventral-lateral amygdala, driven by attentional/salience effects in the central amygdala. Hippocampal activity was similar during both pair types, but a left hippocampal cluster related to successful encoding was observed only for negative pairs. Extra-hippocampal associative memory processes (e.g., unitization) were more effective for neutral than emotional materials. Our findings suggest that reduced emotional association memory is accompanied by increases in activity and functional coupling within the amygdala. This did not disrupt hippocampal association-memory processes, which indeed were critical for successful emotional association memory formation.



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The impact of MEG source reconstruction method on source-space connectivity estimation: A comparison between minimum-norm solution and beamforming

Publication date: 1 August 2017
Source:NeuroImage, Volume 156
Author(s): Ana-Sofía Hincapié, Jan Kujala, Jérémie Mattout, Annalisa Pascarella, Sebastien Daligault, Claude Delpuech, Domingo Mery, Diego Cosmelli, Karim Jerbi
Despite numerous important contributions, the investigation of brain connectivity with magnetoencephalography (MEG) still faces multiple challenges. One critical aspect of source-level connectivity, largely overlooked in the literature, is the putative effect of the choice of the inverse method on the subsequent cortico-cortical coupling analysis. We set out to investigate the impact of three inverse methods on source coherence detection using simulated MEG data. To this end, thousands of randomly located pairs of sources were created. Several parameters were manipulated, including inter- and intra-source correlation strength, source size and spatial configuration. The simulated pairs of sources were then used to generate sensor-level MEG measurements at varying signal-to-noise ratios (SNR). Next, the source level power and coherence maps were calculated using three methods (a) L2-Minimum-Norm Estimate (MNE), (b) Linearly Constrained Minimum Variance (LCMV) beamforming, and (c) Dynamic Imaging of Coherent Sources (DICS) beamforming. The performances of the methods were evaluated using Receiver Operating Characteristic (ROC) curves. The results indicate that beamformers perform better than MNE for coherence reconstructions if the interacting cortical sources consist of point-like sources. On the other hand, MNE provides better connectivity estimation than beamformers, if the interacting sources are simulated as extended cortical patches, where each patch consists of dipoles with identical time series (high intra-patch coherence). However, the performance of the beamformers for interacting patches improves substantially if each patch of active cortex is simulated with only partly coherent time series (partial intra-patch coherence). These results demonstrate that the choice of the inverse method impacts the results of MEG source-space coherence analysis, and that the optimal choice of the inverse solution depends on the spatial and synchronization profile of the interacting cortical sources. The insights revealed here can guide method selection and help improve data interpretation regarding MEG connectivity estimation.



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Freesurfer cortical normative data for adults using Desikan-Killiany-Tourville and ex vivo protocols

Publication date: 1 August 2017
Source:NeuroImage, Volume 156
Author(s): Olivier Potvin, Louis Dieumegarde, Simon Duchesne
We recently built normative data for FreeSurfer morphometric estimates of cortical regions using its default atlas parcellation (Desikan-Killiany or DK) according to individual and scanner characteristics. We aimed to produced similar normative values for Desikan-Killianny-Tourville (DKT) and ex vivo-based labeling protocols, as well as examine the differences between these three atlases. Surfaces, thicknesses, and volumes of cortical regions were produced using cross-sectional magnetic resonance scans from the same 2713 healthy individuals aged 18–94 years as used in the reported DK norms. Models predicting regional cortical estimates of each hemisphere were produced using age, sex, estimated intracranial volume (eTIV), scanner manufacturer and magnetic field strength (MFS) as predictors. The DKT and DK models generally included the same predictors and produced similar R². Comparison between DK, DKT, ex vivo atlases normative cortical measures showed that the three protocols generally produced similar normative values.



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Multi-echo EPI of human fear conditioning reveals improved BOLD detection in ventromedial prefrontal cortex

Publication date: 1 August 2017
Source:NeuroImage, Volume 156
Author(s): Brice Fernandez, Laura Leuchs, Philipp G. Sämann, Michael Czisch, Victor I. Spoormaker
Standard T2* weighted functional magnetic resonance imaging (fMRI) performed with echo-planar imaging (EPI) suffers from signal loss in the ventromedial prefrontal cortex (vmPFC) due to macroscopic field inhomogeneity. However, this region is of special interest to affective neuroscience and psychiatry. The Multi-echo EPI (MEPI) approach has several advantages over EPI but its performance against EPI in the vmPFC has not yet been examined in a study with sufficient statistical power using a task specifically eliciting activity in this region. We used a fear conditioning task with MEPI to compare the performance of MEPI and EPI in vmPFC and control regions in 32 healthy young subjects. We analyzed activity associated with short (12ms), standard (29ms) and long (46ms) echo times, and a voxel-wise combination of these three echo times. Behavioral data revealed successful differentiation of the conditioned versus safety stimulus; activity in the vmPFC was shown by the contrast "safety stimulus > conditioned stimulus" as in previous research and proved significantly stronger with the combined MEPI than standard single-echo EPI. Then, we aimed to demonstrate that the additional cluster extent (ventral extension) detected in the vmPFC with MEPI reflects activation in a relevant cluster (i.e., not just non-neuronal noise). To do this, we used resting state data from the same subjects to show that the time-course of this region was both connected to bilateral amygdala and the default mode network. Overall, we demonstrate that MEPI (by means of the weighted sum combination approach) outperforms standard EPI in vmPFC; MEPI performs always at least as good as the best echo time for a given brain region but provides all necessary echo times for an optimal BOLD sensitivity for the whole brain. This is relevant for affective neuroscience and psychiatry given the critical role of the vmPFC in emotion regulation.



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Editorial Board

Publication date: 15 May 2017
Source:NeuroImage, Volume 152





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Reliable absorbance measurement of liquid samples in soft X-ray absorption spectroscopy in transmission mode

Publication date: Available online 12 May 2017
Source:Journal of Electron Spectroscopy and Related Phenomena
Author(s): Masanari Nagasaka, Hayato Yuzawa, Toshio Horigome, Nobuhiro Kosugi
In soft X-ray absorption spectroscopy in transmission mode (T-mode XAS), it is necessary to optimize the thickness of thin liquid layers for appropriate absorbance around 0.3-0.7 and keep the sample thickness flat within a photon beam. In the present work at the UVSOR Synchrotron Facility, a thin liquid layer is sandwiched between two 100nm thick Si3N4 or SiC membranes of 2×2mm² in a helium chamber with enough working space, and the liquid thickness is optimized by using the elasticity of the membranes under controlling the helium pressure between 0.1013 and 0.12MPa. The flatness of the liquid sample within a photon beam is investigated with measuring position-dependent O K-edge T-mode XAS spectra of liquid water. In the case of the beam size of 50μm and the helium pressure of 0.1090MPa (0.1038MPa), it is confirmed that the liquid water layer has flat thickness around 200nm (320nm) at the center position of 2×2mm² sample area with allowance of ±350μm (±150μm), where the thickness is ca 900nm at the brim of the liquid sample area. The pre-edge vs. main edge (Pre/Main) ratio is 0.38±0.01 for the center of the sample area and becomes considerably larger than 0.38 for the off-center position. The deviation from 0.38 is caused by the inhomogeneous thickness and is evaluated in comparison with a model simulation. The Pre/Main ratio can be used to evaluate the flatness in the liquid sample thickness within the beam area of soft X-rays. Positioning of as small a beam as possible on the center of the liquid sample area is essential to obtain reliable T-mode XAS spectra with the present liquid cells.



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Scholar : These new articles for The American Journal of Drug and Alcohol Abuse are available online

The online platform for Taylor & Francis Online content New for The American Journal of Drug and Alcohol Abuse and online now on Taylor & Francis Online: Reviews Effects of regular cannabis use on neurocognition, brain structure, and function: a systematic review of findings in adults Danilo A. Nader MD & Zila M. Sanchez PhD Pages: 1-15 | DOI: 10.1080/00952990.2017.1306746 The Opiate Epidemic. Click here for the Free Access Article Collection: http://ift.tt/2cHzs7g. To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.