Publication date: July 2018
Source:Materials Science in Semiconductor Processing, Volume 81
Author(s): Woo-Jung Lee, Dae-Hyung Cho, Jae-Hyung Wi, Won Seok Han, Boo-Kyoung Kim, Sang Dae Choi, Ju-Yeoul Baek, Yong-Duck Chung
Chemical bath deposition (CBD)-ZnS is used as a buffer layer for Cu(In,Ga)Se2 (CIGS) solar cell and then, plasma damage originated from the negative oxygen ions or neutral particles with high energy is regarded as an important issue during subsequent deposition of window layer by sputtering process. To avoid negative plasma effects, we newly designed sputtering system with dual deposition mode of low damage sputtering (LDS) process and direct sputtering (DS) process, adjusting plasma direction by dual cylindrical targets. It allows to grow bilayer AZO film by sequentially depositing thin LDS AZO film as a protect layer and thick AZO film as a transparent conducting layer to collect electrons. The physical and electrical characteristics of bilayer AZO film were investigated to verify the positive effect against plasma damage. In plasma damage test using GaAs wafer, we observed that increase of sputtering power leads to a falling-off in electrical qualities by plasma damage. For practical solar cell application, we fabricated three types of CIGS/CBD-ZnS solar cells with LDS AZO film grown at 2 kW and 5 kW (by 1500 mm cylindrical targets) and Conventional-AZO film (by 4-in. circular targets), and demonstrated that the performance of CIGS solar cell with LDS AZO is superior to that with Conventional-AZO film due to the effective protection layer to relieve plasma damage.
http://ift.tt/2p96P54
Δευτέρα 12 Μαρτίου 2018
Characterization of bilayer AZO film grown by low-damage sputtering for Cu(In,Ga)Se2 solar cell with a CBD-ZnS buffer layer
Persistence of TBT and copper in excess on leisure boat hulls around the Baltic Sea
Abstract
A handheld XRF-analyzer specially calibrated for measurements of metals on plastic boat hulls has been used on leisure boats in Denmark (DK), Finland (FI), and Germany (DE). The results on tin and copper are presented as μg metal/cm2. Tin is a proxy for the occurrence of organotin compounds on the boat. Two or three sites were visited in each country and between 25 and 90 boats were measured at each site. Every boat was measured at six to eight places, and the results are presented both as mean and median values. Linear regression of mean to median values of the 377 data pairs shows high relationship with R2 = 0.9566 for tin and R2 of 0.9724 for copper and thus both ways of calculation may be used. However, for regulative use, it is suggested that all individual measurements on each boat should be presented and used for decisions of removal or sealing of boat hulls. The results are compared with published data from different parts of Sweden, i.e., boats in fresh water, brackish water, and salt water. The results show that tin with mean values > 50 μg Sn/cm2 is still found on 42, 24, and 23% of the boats in DK, FI, and DE, respectively. The corresponding percentages based on median values are 38, 22, and 18% for DK, FI, and DE, respectively. The variation among boats is high with a maximum mean value of 2000 μg Sn/cm2. As comparison, one layer of an old TBT antifouling paint Hempels Hard racing superior, corresponds to 300 μg Sn/cm2. The percentage of boats with tin > 400 μg Sn/cm2 content based on mean values was 10% in DK, 5% in FI, and 1% in DE. The corresponding median values were 9, 6, and 1% for DK, FI, and DE. Copper, > 100 μg Cu/cm2, was detected on all measured boats in DK and in DE and on all but 3% of the FI boats. One layer of Hempels MilleXtra corresponds to ̴ 4000 μg Cu/cm2. The recommendation on the can is to apply two layers. The proportion of boats with higher mean copper values than 8000 μg Cu/cm2 was 51, 56, and 61 for boats in DK, FI, and DE, respectively. The proportion based on median values > 8000 μg Cu/cm2 was 50, 54, and 61% for DK, FI, and DE. The conclusion is that many leisure boats around the Baltic Sea still display or possess antifouling paints containing organotin compounds and that more than half of the boats have more copper than needed for one boat season according to the paint producers. Much of these known toxic compounds will probably be released into the environment and harm the biota. The calibrated XRF-method, intended for area measurements on boat hulls, is an easy and cheap way to detect boats with organotin compounds and high copper content. We recommend environmental authorities to use this method for identification of such boats and to use the results for requesting measures to minimize further leakage to the environment.
http://ift.tt/2DmmTWa
Potential harmful elements in coal dust and human health risk assessment near the mining areas in Cherat, Pakistan
Abstract
This study was aimed to investigate the potential harmful element (PHE) concentrations in coal dust and evaluate the human risk assessment and health effects near coal mining areas. For this purpose, dust samples were collected near various coal mines in Cherat, Pakistan, and analyzed for the PHE concentrations. Determined PHE concentrations were evaluated for the health risk assessment. Results revealed that ingestion was the major pathway as compared to others for PHE exposure. Individual chronic daily intake (CDI) of PHEs was higher than their respective permissible exposure limits set for oral exposure routes by the Agency for Toxic Substances and Disease Registry (ATSDR). Chronic risk or health index (HI) values were observed < 1 for all PHEs and in the order of Pb > Cr > Cd > Ni > Cu > Co > Zn. Higher HI values of Pb, Cr, and Cd could attribute to various chronic health problems as observed during the medical examination survey of this study. Cancer risk (CR) values for this study were observed within the US Environmental Protection Agency (EPA) limits. However, if current practices continued, the PHEs will cross these limits in a near future. Therefore, this study strongly recommends the provision of safety measures, rules, and regulation to avoid health hazards in the future.
http://ift.tt/2p3zY23
Effect of dietary phytogenics (herbal mixture) supplementation on growth performance, nutrient utilization, antioxidative properties, and immune response in broilers
Abstract
This experiment was conducted to study that effect of a phytogenics (herbal mixture) supplementation as alternative to antibiotics on the growth performance and immune response in broilers. Three thousand broiler male chicks at 1 day of age were housed in floor pens and divided into five experimental groups with five replicates of 120 birds each. The first group was fed the basal diet without any additive in feed or water; the second group was fed the basal diet, and the drinking water was supplemented with mixture of antibiotics (Doxycycline 1 g/5 L + Colistine sulfate 1 g/5 L) for the first 10 days of life. The other three treatments of chickens were fed the control diet supplemented with herbal mixture at a level of 0.5, 1.0, and 1.5 kg/ton, respectively. Dietary herb mixture supplementation improved growth performance significantly in comparison with control group. In addition, herb mixture supplementation reduced plasma total cholesterol and triglycerides concentrations, whereas, high density lipoprotein HDL-cholesterol and glutathione peroxidase (GPX) were increased significantly. Furthermore, herb mixture supplementation increased plasma levels of total protein and antibodies titers for Newcastle disease virus before and after the infection. It could be concluded that dietary herb mixture supplementation had positive effects on growth performance, antioxidative properties, and humoral immunity in broiler chickens.
http://ift.tt/2DmmLGa
Comparison of nickel adsorption on biochars produced from mixed softwood and Miscanthus straw
Abstract
In order to understand the influence of feedstock type on biochar adsorption of heavy metals, the adsorption characteristics of nickel (Ni2+), copper (Cu2+) and lead (Pb2+) onto biochars derived from mixed softwood and Miscanthus straw were compared. The biochars were produced from mixed softwood pellets (SWP) and Miscanthus straw pellets (MSP), at both 550 and 700 °C for each material, using a standardised production procedure recommended by the UK Biochar Research Centre. Kinetics analyses show that the adsorption of Ni2+ to all four biochars reached equilibrium within 5 min. The degree of Ni2+ removal for all four biochars remained nearly constant within initial pH values of 3–8, because the equilibrium pH values within this range were similar due to the buffering effect of the biochars. A sharp increase of Ni2+ removal percentage for all biochars at initial solution pH 8–10 was observed as the equilibrium pH also increased. MSP derived biochars generally had higher maximum adsorption capacities (Qmax) for the three tested metals as compared with those from SWP, which was likely due to their higher degree of carbonisation during production. This study shows that feedstock type is a primary factor affecting the adsorption capacities of the tested biochars for heavy metals.
http://ift.tt/2p4B3aa
Effect of composition and microstructure of humic acid on 3,3′,4,4′-tetrachlorobiphenyl sorption
Abstract
The fate and transport of polychlorinated biphenyls (PCBs), a class of persistent organic compounds, in soils was markedly affected by their sorption/desorption on soil organic matters (SOM) due to high hydrophobicity of PCBs. Humic acid (HA), an important fraction of SOM, has no steady composition and microstructure from different origins, resulting in their diverse sorption capacity. Therefore, the effect of composition and microstructure of HA on sorption of 3,3′,4,4′-tetrachlorobiphenyl (PCB77) was investigated in this study. The primary sorption mechanism of PCB77 on HAs was also demonstrated by using Fourier transform infrared (FTIR) and solid-state carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopy analysis. Elemental content analysis of three HAs showed that the content of unsaturated C (the total of aromatic, carboxylic, and carbonyl carbon) followed an order of YHA>SHA>AHA. Furthermore, YHA and SHA had remarkably rough and complicated particle surfaces but AHA had relatively smooth surface and the well-proportioned and interspersed particle sizes. The results of the sorption experiment showed that the sorption capacity of PCB77 on HAs followed a similar order of YHA>SHA>AHA, indicating the content of unsaturated C of HAs controlled the sorption of PCB77 on HAs. Sorption of PCB77 on either AHA or SHA did not change with increasing ionic strength of background solution, implying that there was no H-bond or electrostatic interaction between PCB77 and HAs. The result of FTIR and 13C-NMR spectra showed the primarily possible mechanism was π-π conjugative interaction and hydrophobic binding between PCB77 and HAs.
http://ift.tt/2DmOtlT
The use of probiotics as eco-friendly alternatives for antibiotics in poultry nutrition
Abstract
Antibiotics as growth promoters in poultry have been used for long time for improving feed efficiency and performance. Due to their various side-effects such as antibiotic resistance, destruction of beneficial bacteria in the gut, and dysbiosis, it is required to think about some alternatives. Probiotics are one of the options in this regard for improving poultry production. Probiotics are defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." They are available in various forms for use as feed additives. Probiotics as feed additives aid in proper digestion of feed hence make the nutrients available for faster growth. Immunity can also be improved by addition of probiotics to poultry diets. Moreover, probiotics aid in improving meat and egg quality traits. Various infectious diseases of poultry can be countered by use of probiotics in their feed. A proper selection of probiotic strains is required for gaining optimal effects. This review focuses on the mechanisms of action of probiotics and their importance in poultry feed supplementation for enhancing production and safeguarding health of poultry.
http://ift.tt/2p4XJXE
Comparative study on the toxic effects of some heavy metals on the Nile Tilapia, Oreochromis niloticus , in the Middle Delta, Egypt
Abstract
Heavy metals are the most dangerous hazards affecting aquatic biota in Egypt specially the Nile Tilapia, Oreochromis niloticus, which is an important species in commercial fisheries. Some areas were not fully studied to screen the hazards that may affect this economic fish. Therefore, the present study aimed to evaluate the potential hazards of heavy metals on O. niloticus in Al-Gharbiya Governorate in the Middle delta of Egypt. Water and fish samples were collected from Al-Qased canal, Kafr El-Zayaat Nile, El-Maash canal in Al-Gharbiya Governorate plus a reference site which is a fish farm at the Faculty of Agriculture, Damietta University, Damitta Governorate, Egypt. The results showed a significant increase (p < 0.05) in the lead, zinc, magnesium, manganese, and copper levels while showed a significant decrease (p < 0.05) in the iron level in the water from all the investigated areas. Cadmium level was significantly high (p < 0.05) in Kafr El-Zayaat Nile and EL-Maash canal only. These metals were also accumulated in the fish livers and gills. Consequently, ALT and AST activities and creatinine level were significantly (p < 0.05) high in all the investigated areas. Histopathological examination revealed cytoplasmic and nuclear degeneration in the hepatocytes in all the investigated areas. Renal glomeruli and Bowman's capsule were not completely intact in Al-Qased and El-Maash canals while conspicuous shrinkage of the glomeruli was determined in Kafr El-Zayaat Nile. Furthermore, slight damage in the secondary lamellae was detected in the gill from Al-Qased canal while in the other areas appeared vacuolated or destructed. Finally, spleen sections of fish from different sites showed the absence of melanin pigments and some vacuoles. In conclusion, the Nile Tilapia, Oreochromis niloticus, is affected by the toxic effects of the heavy metals in Al-Gharbiya Governorate in Egypt and this gives an alarm and should be taken into consideration.
http://ift.tt/2DlhYov
A dual-permeability hydro-biodegradation model for leachate recirculation and settlement in bioreactor landfills
Abstract
A dual-permeability hydro-biodegradation model is developed to describe the leachate flow in municipal solid waste (MSW) and predict the long-term settlement induced by biodegradation in bioreactor landfills. The model is verified against Hydrus-1D and a recirculation experiment conducted in a full-scale landfill. Preferential flow and mass transfer between fissure and matrix can be reasonably modeled by the proposed model. A higher recirculation flow rate can speed up the stabilization process of landfill. However, too much recirculation leachate is not economical and environmental friendly. A stabilization speed index and a leachate utilization index are adopted to evaluate the stabilization speed of bioreactor landfill and utilization rate of leachate, respectively, and the optimal recirculation flow rate is estimated. A flow rate of q = 5 × 10−5–5 × 10−4 m/h (equivalent to recirculation intensity of Q = 15–150 L/tonwaste/year) is recommended for recirculation, which has been verified by the field data in numerous bioreactor landfills.
http://ift.tt/2p4Xvjg
Performance and efficiency of removal of pharmaceutical compounds from hospital wastewater by lab-scale biological treatment system
Abstract
The fate of pharmaceuticals after discharged from hospital into wastewater was clarified experimentally by using a new lab-scale conventional activated sludge (CAS) treatment reactor. The 43 target compounds belong to nine therapeutic classes (antivirals, antibacterials, anticancer drugs, psychotropics, antihypertensives, analgesic–antipyretics, contrast media, herbal medicines, and phytoestrogens) were selected with inclusion of 16 newly estimated compounds. The efficiency of the present reactor was estimated by comparing the reaction rate constant of the solid-water partition coefficients (log Kd) between liquid and solid samples and half-life during 48-h experiment obtained by using hospital effluents with those obtained by using STP wastewater. The results that no significant difference in removal efficiency was observed between both water samples (P > 0.05) indicate high reliability of the present lab-scale reactor. The actual rates of removal when hospital effluent was applied varied widely (mean, 59 ± 40%) independent of type of the pharmaceuticals. More than 90% of 17 compounds were removed after 8 h of treatment. However, the values for psychotropics (mean, 19 ± 26%) and contrast media (mean, 24 ± 17%) were generally low, indicating high stability. The log Kd values ranged from 1.3 to 4.8. Notably, clarithromycin, acridine, and glycitein could be removed in both liquid and solid phases. The dominant removal mechanisms were found to be different for individual pharmaceutical. These results suggest the effectiveness of introduction of the lab-scale biological treatment system for development of a new solution for discharge of pharmaceuticals from hospital.
http://ift.tt/2DnbFAA
Effect of compression ratio, nozzle opening pressure, engine load, and butanol addition on nanoparticle emissions from a non-road diesel engine
Abstract
Currently, diesel engines are more preferred over gasoline engines due to their higher torque output and fuel economy. However, diesel engines confront major challenge of meeting the future stringent emission norms (especially soot particle emissions) while maintaining the same fuel economy. In this study, nanosize range soot particle emission characteristics of a stationary (non-road) diesel engine have been experimentally investigated. Experiments are conducted at a constant speed of 1500 rpm for three compression ratios and nozzle opening pressures at different engine loads. In-cylinder pressure history for 2000 consecutive engine cycles is recorded and averaged data is used for analysis of combustion characteristics. An electrical mobility-based fast particle sizer is used for analyzing particle size and mass distributions of engine exhaust particles at different test conditions. Soot particle distribution from 5 to 1000 nm was recorded. Results show that total particle concentration decreases with an increase in engine operating loads. Moreover, the addition of butanol in the diesel fuel leads to the reduction in soot particle concentration. Regression analysis was also conducted to derive a correlation between combustion parameters and particle number emissions for different compression ratios. Regression analysis shows a strong correlation between cylinder pressure-based combustion parameters and particle number emission.
http://ift.tt/2p3uPHE
Influence of tooth position on wind instrumentalists’ performance and embouchure comfort
Abstract
Purpose
To systematically search the scientific literature concerning the influence of tooth position on wind instrumentalists' performance and embouchure comfort.
Methods
The PubMed, Cochrane, and Embase databases were searched up to November 2017. The main orthodontic journals were searched for papers older than the inception date of PubMed. Grey literature was sought via Google Scholar. Eligible studies were critically appraised and analysed.
Results
The searches retrieved 54 papers. Only two met the inclusion criteria. Searching the orthodontic journals and Google Scholar resulted in two additional eligible studies. All four studies had a cross-sectional design. The sample sizes ranged from 20–100 participants, varying from children to professional musicians. Because of a large heterogeneity in outcome variables, no meta-analysis could be performed. Descriptive analysis shows that there are indications that tooth irregularities have a negative influence on embouchure comfort and performance of a wind instrument player. A large overjet may impede the embouchure of brass musicians and may have a negative influence on trumpet player performance. A wide jaw form seems more beneficial to trumpet player performance than a small jaw form. Furthermore, players of all types of wind instruments can experience embouchure difficulties from extreme spacing or an open bite.
Conclusion
Tooth position can influence musical performance and embouchure comfort of wind instrumentalists. A Class I relationship without malocclusion seems appropriate for every type of wind instrument. The more extreme the malocclusion, the greater the interference with wind instrumentalists' performance and embouchure comfort. Evidence however is limited.
http://ift.tt/2Hs3K7N
Influence of tooth position on wind instrumentalists’ performance and embouchure comfort
Abstract
Purpose
To systematically search the scientific literature concerning the influence of tooth position on wind instrumentalists' performance and embouchure comfort.
Methods
The PubMed, Cochrane, and Embase databases were searched up to November 2017. The main orthodontic journals were searched for papers older than the inception date of PubMed. Grey literature was sought via Google Scholar. Eligible studies were critically appraised and analysed.
Results
The searches retrieved 54 papers. Only two met the inclusion criteria. Searching the orthodontic journals and Google Scholar resulted in two additional eligible studies. All four studies had a cross-sectional design. The sample sizes ranged from 20–100 participants, varying from children to professional musicians. Because of a large heterogeneity in outcome variables, no meta-analysis could be performed. Descriptive analysis shows that there are indications that tooth irregularities have a negative influence on embouchure comfort and performance of a wind instrument player. A large overjet may impede the embouchure of brass musicians and may have a negative influence on trumpet player performance. A wide jaw form seems more beneficial to trumpet player performance than a small jaw form. Furthermore, players of all types of wind instruments can experience embouchure difficulties from extreme spacing or an open bite.
Conclusion
Tooth position can influence musical performance and embouchure comfort of wind instrumentalists. A Class I relationship without malocclusion seems appropriate for every type of wind instrument. The more extreme the malocclusion, the greater the interference with wind instrumentalists' performance and embouchure comfort. Evidence however is limited.
http://ift.tt/2Hs3K7N
As(V) and Sb(V) co-adsorption onto ferrihydrite: synergistic effect of Sb(V) on As(V) under competitive conditions
Abstract
Competitive adsorption of As(V) and Sb(V) at environmentally relevant concentrations onto ferrihydrite was investigated. Batch experiments and XPS analyses confirmed that in a binary system, the presence of Sb(V) exhibited a slight synergistic effect on As(V) adsorption. XPS analyses showed that As(V) and Sb(V) adsorption led to obvious diminishment of Fe–O–Fe and Fe–O–H bonds respectively. At pH of 9, a more significant decrease of Fe–O–Fe was observed in the binary system than that in a single system, indicating that As(V) displayed an even stronger interaction with lattice oxygen atoms under competitive conditions. Basically, ionic strength demonstrated a negligible or positive influence on As(V) and Sb(V) adsorption in binary system. Study of adsorption sequence also indicated that the presence of Sb(V) showed a promotion effect on As(V) adsorption at neutral pHs. Considering that co-contamination of As and Sb in waters has been of great concern throughout the world, our findings contributed to a better understanding of their distribution, mobility, and fate in environment.
http://ift.tt/2DiTETX
MucoLox Formulation to Mitigate Mucositis Symptoms in Head/Neck Cancer
Interventions: Drug: MucoLox; Drug: Sodium Bicarbonate
Sponsors: Carolinas Healthcare System; Professional Compounding Centers of America
Not yet recruiting
http://ift.tt/2HqsHAb
Sound Therapy for Tinnitus Relief in Cochlear Implant Users
Intervention: Device: CART sound therapy
Sponsor: Cochlear
Recruiting
http://ift.tt/2FO1LNX
Antibiotics resistance of Helicobacter pylori in children with upper gastrointestinal symptoms in Hangzhou, China
Abstract
Background
The decreasing eradication rate of Helicobacter pylori is mainly because of the progressive increase in its resistance to antibiotics. Studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to investigate the resistance rates and patterns of H. pylori strains isolated from children.
Materials and Methods
Gastric mucosa biopsy samples obtained from children who had undergone upper gastrointestinal endoscopy were cultured for H. pylori, and susceptibility to six antibiotics (clarithromycin, amoxicillin, gentamicin, furazolidone, metronidazole, and levofloxacin) was tested from 2012-2014.
Results
A total of 545 H. pylori strains were isolated from 1390 children recruited. The total resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin were 20.6%, 68.8%, and 9.0%, respectively. No resistance to amoxicillin, gentamicin, and furazolidone was detected. 56.1% strains were single resistance, 19.6% were resistant to more than one antibiotic, 16.7% for double resistance, and 2.9% for triple resistance in 413 strains against any antibiotic. And the H. pylori resistance rate increased significantly from 2012-2014. There was no significant difference in the resistance rates to clarithromycin, metronidazole, and levofloxacin between different gender, age groups, and patients with peptic ulcer diseases or nonulcer diseases.
Conclusions
Antibiotic resistance was indicated in H. pylori strains isolated from children in Hangzhou, and it increased significantly during the 3 years. Our data strongly support current guidelines, which recommend antibiotic susceptibility tests prior to eradication therapy.
http://ift.tt/2FH74P5
Effect of GaAlAs low-level laser therapy on mouth opening after orthognathic surgery
Abstract
To evaluate low-level laser therapy (LLLT) as an adjunct to enhance postoperative mouth opening after orthognathic surgery. Prospective clinical trial of 82 patients allocated into an intervention group (laser, LG) and a control group (no laser, CG) and subgroups according to the procedure type : (1) surgically assisted rapid maxillary expansion (SARME); (2) maxillary surgery; (3) mandibular surgery; or (4) bimaxillary surgery. LG patients received LLLT immediately after surgery and every 24 h thereafter for 3 days, using a gallium–aluminum–arsenide (GaAlAs) diode laser (780 nm, 28 spots, 14 on each side of the face, output power 2 J/spot). Maximum mouth opening was measured using digital calipers at five time points: preoperative baseline and postoperative days 2, 7, 14, and 21. ANOVA was used to evaluate difference in mouth opening across groups. Significance was accepted at P ≤ 0.05. Final average mouth opening differed between women (GL1 = 94.24%, GC1 = 89.54%, GL2 = 69.39%; GC2 = 68.46%; GL3 = 65.11%; GC3 = 58.64%; GL4 = 61.85%; GC4 = 57.11%) and men (GL1 = 86.92%, GC1 = 102.44%, GL2 = 77.56%; GC2 = 81.65%; GL3 = 80.29%; GC3 = 67.63%; GL4 = 66.93%; GC4 = 55.31%). There were no significant differences between the SARME and isolated maxillary/mandibular surgery groups. In the bimaxillary groups, average mouth opening was increased in all patients who received LLLT, significantly so in male patients. LLLT with a GaAlAs diode laser (780 nm) did not affect postoperative mouth opening after SARME, isolated maxillary surgery, or isolated mandibular surgery. However, it improved mouth opening in men who had undergone bimaxillary orthognathic surgery.
http://ift.tt/2p6rAyj
Bacterial community changes in response to oil contamination and perennial crop cultivation
Abstract
We investigated bacterial community dynamics in response to used motor oil contamination and perennial crop cultivation by 16S rRNA gene amplicon sequencing in a 4-year field study. Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria, and Gemmatimonadetes were the major bacterial phyla, and Rhodococcus was the most abundant genus. Initially, oil contamination decreased the overall bacterial diversity. Actinobacteria, Betaproteobacteria, and Gammaproteobacteria were sensitive to oil contamination, exhibiting clear succession with time. However, bacterial communities changed over time, regardless of oil contamination and crop cultivation. The abundance difference of most OTUs between oil-contaminated and non-contaminated plots remained the same in later sampling years after the initial abundance difference induced by oil spike. The abundances of three oil-favored actinobacteria (Lysinimonas, Microbacteriaceae, and Marmoricola) and one betaproteobacterium (Aquabacterium) changed in different manner over time in oil-contaminated and non-contaminated soil. We propose that these taxa are potential bio-indicators for monitoring recovery from motor oil contamination in boreal soil. The effect of crop cultivation on bacterial communities became significant only after the crops achieved stable growth, likely associated with plant material decomposition by Bacteroidetes, Armatimonadetes and Fibrobacteres.
http://ift.tt/2tE3Oit
Scholar : These new articles for Cogent Geoscience are available online
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Changes in neural activation underlying attention processing of emotional stimuli following treatment with positive search training in anxious children
Source:Journal of Anxiety Disorders
Author(s): Allison M. Waters, Yuan Cao, Rachel Kershaw, Georg M. Kerbler, David H.K. Shum, Melanie J. Zimmer-Gembeck, Michelle G. Craske, Brendan P. Bradley, Karin Mogg, Daniel S. Pine, Ross Cunnington
Prior research indicates that positive search training (PST) may be a promising home-based computerised treatment for childhood anxiety disorders. It explicitly trains anxious individuals in adaptive, goal-directed attention-search strategies to search for positive and calm information and ignore goal-irrelevant negative cues. Although PST reduces anxiety symptoms, its neural effects are unknown. The main aim of this study was to examine changes in neural activation associated with changes in attention processing of positive and negative stimuli from pre- to post-treatment with PST in children with anxiety disorders. Children's neural activation was assessed with functional magnetic resonance imaging (fMRI) during a visual-probe task indexing attention allocation to threat-neutral and positive-neutral pairs. Results showed pre- to post-treatment reductions in anxiety symptoms and neural reactivity to emotional faces (angry and happy faces, relative to neutral faces) within a broad neural network linking frontal, temporal, parietal and occipital regions. Changes in neural reactivity were highly inter-correlated across regions. Neural reactivity to the threat-bias contrast reduced from pre- to post-treatment in the mid/posterior cingulate cortex. Results are considered in relation to prior research linking anxiety disorders and treatment effects with functioning of a broad limbic-cortical network involved in emotion reactivity and regulation, and integrative functions linking emotion, memory, sensory and motor processes and attention control.
http://ift.tt/2p3uV1V
Body composition and metabolic changes during a 520-day mission simulation to Mars
Abstract
Purpose
The "Mars-500 project" allowed to evaluate the changes in psychological/physiological adaptation over a prolonged confinement, in order to gather information for future missions. Here, we evaluated the impact of confinement and isolation on body composition, glucose metabolism/insulin resistance and adipokine levels.
Methods
The "Mars-500 project" consisted of 520 consecutive days of confinement from June 3, 2010 to Nov 4, 2011. The crew was composed of six male subjects (three Russians, two Europeans, and one Chinese) with a median age of 31 years (range 27–38 years).
Results
During the 520-day confinement, total body mass and BMI progressively decreased, reaching a significant difference at the end (417 days) of the observation period (− 9.2 and − 5.5%, respectively). Fat mass remained unchanged. A progressive and significant increase of fasting plasma glucose was observed between 249 and 417 days (+ 10/+ 17% vs baseline), with a further increase at the end of confinement (up to + 30%). Median plasma insulin showed a non-significant early increment (60 days; + 86%). Total adiponectin halved (− 47%) 60 days after hatch closure, remaining at this nadir (− 51%) level for a further 60 days. High molecular weight adiponectin remained significantly lower from 60 to 168 days.
Conclusions
Based on these data, countermeasures may be envisioned to balance the potentially harmful effects of prolonged confinement, including a better exercise program, with accurate monitoring of (1) the individual activity and (2) the relationship between body composition and metabolic derangement.
http://ift.tt/2FvBLr2
Exenatide exerts cognitive effects by modulating the BDNF-TrkB neurotrophic axis in adult mice
Publication date: April 2018
Source:Neurobiology of Aging, Volume 64
Author(s): Manuela Bomba, Alberto Granzotto, Vanessa Castelli, Noemi Massetti, Elena Silvestri, Lorella M.T. Canzoniero, Annamaria Cimini, Stefano L. Sensi
Modulation of insulin-dependent signaling is emerging as a valuable therapeutic tool to target neurodegeneration. In the brain, the activation of insulin receptors promotes cell growth, neuronal repair, and protection. Altered brain insulin signaling participates in the cognitive decline seen in Alzheimer's disease patients and the aging brain. Glucagon-like peptide-1 (GLP-1) regulates insulin secretion and, along with GLP-1 analogues, enhances neurotrophic signaling and counteracts cognitive deficits in preclinical models of neurodegeneration. Moreover, recent evidence indicates that GLP-1 modulates the activity of the brain-derived neurotrophic factor (BDNF). In this study, in adult wild-type mice, here employed as a model of mid-life brain aging, we evaluated the effects of a 2-month treatment with exenatide, a GLP-1 analogue. We found that exenatide promotes the enhancement of long-term memory performances. Biochemical and imaging analyses show that the drug promotes the activation of the BDNF-TrkB neurotrophic axis and inhibits apoptosis by decreasing p75NTR-mediated signaling. The study provides preclinical evidence for the use of exenatide to delay age-dependent cognitive decline.
Graphical abstract
http://ift.tt/2GiYdkt
Mutation burden profile in familial Alzheimer's disease cases from India
Source:Neurobiology of Aging, Volume 64
Author(s): Adhikarla Syama, Somdatta Sen, Lakshmi Narayanan Kota, Biju Viswanath, Meera Purushottam, Mathew Varghese, Sanjeev Jain, Mitradas M. Panicker, Odity Mukherjee
This study attempts to identify coding risk variants in genes previously implicated in Alzheimer's disease (AD) pathways, through whole-exome sequencing of subjects (N = 17) with AD, with a positive family history of dementia (familial AD). We attempted to evaluate the mutation burden in genes encoding amyloid precursor protein metabolism and previously linked to risk of dementias. Novel variants were identified in genes involved in amyloid precursor protein metabolism such as PSEN1 (chr 14:73653575, W161C, tgg > tgT), PLAT (chr 8:42039530,G272R), and SORL1 (chr11:121414373,G601D). The mutation burden assessment of dementia-related genes for all 17 cases revealed 45 variants, which were either shared across subjects, or were present in just the 1 patient. The study shows that the clinical characteristics, and genetic correlates, obtained in this sample are broadly comparable to the other studies that have investigated familial forms of AD. Our study identifies rare deleterious genetic variations, in the coding region of genes involved in amyloid signaling, and other dementia-associated pathways.
http://ift.tt/2Dk7PZ5
Levodopa improves response inhibition and enhances striatal activation in early-stage Parkinson's disease
Source:Neurobiology of Aging, Volume 66
Author(s): Peter Manza, Guy Schwartz, Mala Masson, Sarah Kann, Nora D. Volkow, Chiang-shan R. Li, Hoi-Chung Leung
Dopaminergic medications improve the motor symptoms of Parkinson's disease (PD), but their effect on response inhibition, a critical executive function, remains unclear. Previous studies primarily enrolled patients in more advanced stages of PD, when dopaminergic medication loses efficacy, and patients were typically on multiple medications. Here, we recruited 21 patients in early-stage PD on levodopa monotherapy and 37 age-matched controls to perform the stop-signal task during functional magnetic resonance imaging. In contrast to previous studies reporting null effects in more advanced PD, levodopa significantly improved response inhibition performance in our sample. No significant group differences were found in brain activations to pure motor inhibition or error processing (stop success vs. error trials). However, relative to controls, the PD group showed weaker striatal activations to salient events (infrequent vs. frequent events: stop vs. go trials) and fronto-striatal task-residual functional connectivity; both were restored with levodopa. Thus, levodopa appears to improve an important executive function in early-stage PD via enhanced salient signal processing, shedding new light on the role of dopaminergic signaling in response inhibition.
http://ift.tt/2Gi7toJ
Polygenic risk for Alzheimer's disease influences precuneal volume in two independent general populations
Source:Neurobiology of Aging, Volume 64
Author(s): Jin Li, Xiaolong Zhang, Ang Li, Shu Liu, Wen Qin, Chunshui Yu, Yong Liu, Bing Liu, Tianzi Jiang
Alzheimer's disease (AD) is heritable with complex genetic underpinnings. Based on previous results from large-scale genome-wide association studies, recent studies found an association between the polygenic risk score (PGRS) of AD and the structure of some preselected brain regions, but the effects of AD PGRS on all voxels of the brain have not been fully investigated. In the present study, we examined the voxel-wise effect of AD PGRS on the entire brain and the influence of AD PGRS on cognitive function in 2 independent healthy young cohorts. In both cohorts, an elevated AD PGRS was associated with a smaller precuneal volume, and the effect remained after excluding the APOE genotype. No correlation was found between AD PGRS and any cognitive measure in either sample. Finding a negative correlation between the AD PGRS and the precuneal volume could help to elucidate the mechanism of the genetic risk for AD and could provide a potential biomarker for early detection and possible interventions in AD.
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Multimodal neuroimaging and behavioral assessment of α-synuclein polymorphism rs356219 in older adults
Source:Neurobiology of Aging, Volume 66
Author(s): Roxana G. Burciu, Rachael D. Seidler, Priyank Shukla, Mike A. Nalls, Andrew B. Singleton, Michael S. Okun, David E. Vaillancourt
The single-nucleotide polymorphism rs356219 in the α-synuclein (SNCA) gene has been shown to significantly contribute to an earlier age at onset of Parkinson's disease (PD), and regulates SNCA expression in PD brain regions, blood, and plasma. Here, we used multimodal magnetic resonance imaging (MRI) to study healthy adults with and without the rs356219 risk genotype. Motor and cognitive tests were administered, and all participants underwent functional and structural MRI. Imaging analyses included (1) task-based functional MRI; (2) task-based functional connectivity; (3) free-water diffusion MRI of the substantia nigra; (4) voxel-based morphometry; and (5) surface-based morphometry. There were no differences between the 2 groups in motor and cognitive performance, or brain structure. However, carrying a PD risk variant was associated with reduced functional activity in the posterior putamen and primary motor cortex. Moreover, the posterior putamen had reduced functional connectivity with the motor cortex during motor control in those with a risk genotype compared to those without. These findings point to functional abnormalities in the striatocortical circuit of rs356219 risk genotype carriers.
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Editorial Advisory Board
Source:Neurobiology of Aging, Volume 64
http://ift.tt/2Dkn18H
White matter hyperintensities and vascular risk factors in monozygotic twins
Source:Neurobiology of Aging, Volume 66
Author(s): Mara ten Kate, Carole H. Sudre, Anouk den Braber, Elles Konijnenberg, Michel G. Nivard, M. Jorge Cardoso, Philip Scheltens, Sébastien Ourselin, Dorret I. Boomsma, Frederik Barkhof, Pieter Jelle Visser
Cerebral white matter hyperintensities (WMHs) have been associated with vascular risk factors, both of which are under genetic influence. We examined in a monozygotic twin sample whether the association between vascular risk and WMHs is influenced by overlapping genetic factors. We included 195 cognitively normal monozygotic twins (age = 70 ± 7 years), including 94 complete pairs. Regional WMH load was estimated using an automated algorithm. Vascular risk was summarized with the Framingham score. The within–twin pair correlation for total WMHs was 0.76 and for Framingham score was 0.77. Within participants, Framingham score was associated with total and periventricular WMHs (r = 0.32). Framingham score in 1 twin was also associated with total WMHs in the co-twin (r = 0.26). Up to 83% of the relation between both traits could be explained by shared genetic effects. In conclusion, monozygotic twins have highly similar vascular risk and WMH burden, confirming a genetic background for these traits. The association between both traits is largely driven by overlapping genetic factors.
http://ift.tt/2FtLjD9
Amyloid pathology in the progression to mild cognitive impairment
Source:Neurobiology of Aging, Volume 64
Author(s): Philip S. Insel, Oskar Hansson, R. Scott Mackin, Michael Weiner, Niklas Mattsson
The objective of this study was to determine the cognitive and functional decline and development of brain injury in individuals progressing from preclinical (β-amyloid positive cognitively normal) to prodromal Alzheimer's disease (AD) (β-amyloid positive mild cognitive impairment [MCI]), and compare this with individuals who progress to MCI in the absence of significant amyloid pathology. Seventy-five cognitively healthy participants who progressed to MCI were followed for 4 years on average and up to 10 years. We tested effects of β-amyloid (Aβ) on measures of cognition, functional status, depressive symptoms, and brain structure and metabolism. Preclinical AD subjects showed greater cognitive decline in multiple domains and increased cerebrospinal fluid phosphorylated tau levels at baseline while Aβ-negative progressors showed increased rates of white matter hyperintensity accumulation and had a greater frequency of depressive symptoms at baseline. Aβ status did not influence patterns of brain atrophy, but preclinical AD subjects showed greater decline of brain metabolism than Aβ-negative progressors. Several unique features separate the transition from preclinical to prodromal AD from other causes of cognitive decline. These features may facilitate early diagnosis and treatment of AD, especially in clinical trials aimed at halting the progression from preclinical to prodromal AD.
http://ift.tt/2FBgdFx
Estimates of age-dependent cutoffs for pathological brain volume loss using SIENA/FSL—a longitudinal brain volumetry study in healthy adults
Source:Neurobiology of Aging, Volume 65
Author(s): Roland Opfer, Ann-Christin Ostwaldt, Maria Pia Sormani, Carola Gocke, Christine Walker-Egger, Praveena Manogaran, Nicola De Stefano, Sven Schippling
Brain volume loss (BVL) has gained increasing interest for monitoring tissue damage in neurodegenerative diseases including multiple sclerosis (MS). In this longitudinal study, 117 healthy participants (age range 37.3–82.6 years) received at least 2 magnetic resonance imaging examinations. BVL (in %) was determined with the Structural Image Evaluation using Normalisation of Atrophy/FMRIB Software Library and annualized. Mean BVL per year was 0.15%, 0.30%, 0.46%, and 0.61% at ages 45, 55, 65, and 75 years, respectively. The corresponding BVL per year values of the age-dependent 95th percentiles were 0.52%, 0.77%, 1.05% and 1.45%. Pathological BVL can be assumed if an individual BVL per year exceeds these thresholds for a given age. The mean BVL per year determined in this longitudinal study was consistent with results from a cross-sectional study that was published recently. The cut-off for a pathological BVL per year at the age of 45 years (0.52%) was consistent with the cut-off suggested previously to distinguish between physiological and pathological BVL in MS patients. Different cut-off values, however, need to be considered when interpreting BVL assessed in cohorts of higher ages.
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ATXN1 intermediate-length polyglutamine expansions are associated with amyotrophic lateral sclerosis
Source:Neurobiology of Aging, Volume 64
Author(s): Serena Lattante, Maria Grazia Pomponi, Amelia Conte, Giuseppe Marangi, Giulia Bisogni, Agata Katia Patanella, Emiliana Meleo, Christian Lunetta, Nilo Riva, Lorena Mosca, Paola Carrera, Marco Bee, Marcella Zollino, Mario Sabatelli
To clarify the possible involvement of intermediate ATXN1 alleles as risk factors for amyotrophic lateral sclerosis (ALS), we tested ATXN1 in a cohort of 1146 Italian ALS patients, previously screened for variants in other ALS genes, and in 529 controls. We detected ATXN1 alleles with ≥33 polyglutamine repeats in 105 of 1146 patients (9.16%) and 29 of 529 controls (5.48%) (p = 0.003). The frequency of ATXN1 alleles with ≥33 polyglutamine repeats was particularly high in the group of ALS patients carrying the C9orf72 expansion (12/59, 20.3%). We confirmed this result in an independent cohort of C9orf72 Italian patients (10/80 cases, 12.5%), thus finding a cumulative frequency of ATXN1 expansion of 15.82% in C9orf72 carriers (p = 2.40E-05). Our results strongly support the hypothesis that ATXN1 could act as a disease risk gene in ALS, mostly in C9orf72 expansion carriers. Further studies are needed to confirm our results and to define the mechanism by which ATXN1 might contribute to neuronal degeneration leading to ALS.
http://ift.tt/2Dk7NAr
Age-related differences in orienting attention to sound object representations
Source:Neurobiology of Aging, Volume 66
Author(s): Claude Alain, Madeline Cusimano, Linda Garami, Kristina C. Backer, Bettina Habelt, Vanessa Chan, Lynn Hasher
We examined the effect of age on listeners' ability to orient attention to an item in auditory short-term memory (ASTM) using high-density electroencephalography, while participants completed a delayed match-to-sample task. During the retention interval, an uninformative or an informative visual retro-cue guided attention to an item in ASTM. Informative cues speeded response times, but only for young adults. In young adults, informative retro-cues generated greater event-related potential amplitude between 450 and 650 ms at parietal sites, and an increased sustained potential over the left central scalp region, thought to index the deployment of attention and maintenance of the cued item in ASTM, respectively. Both modulations were reduced in older adults. Alpha and low beta oscillatory power suppression was greater when the retro-cue was informative than uninformative, especially in young adults. Our results point toward an age-related decline in orienting attention to the cued item in ASTM. Older adults may be dividing their attention between all items in working memory rather than selectively focusing attention on a single cued item.
http://ift.tt/2GhoDTt
Abnormalities of resting-state functional cortical connectivity in patients with dementia due to Alzheimer's and Lewy body diseases: an EEG study
Publication date: May 2018
Source:Neurobiology of Aging, Volume 65
Author(s): Claudio Babiloni, Claudio Del Percio, Roberta Lizio, Giuseppe Noce, Susanna Lopez, Andrea Soricelli, Raffaele Ferri, Flavio Nobili, Dario Arnaldi, Francesco Famà, Dag Aarsland, Francesco Orzi, Carla Buttinelli, Franco Giubilei, Marco Onofrj, Fabrizio Stocchi, Paola Stirpe, Peter Fuhr, Ute Gschwandtner, Gerhard Ransmayr, Heinrich Garn, Lucia Fraioli, Michela Pievani, Giovanni B. Frisoni, Fabrizia D'Antonio, Carlo De Lena, Bahar Güntekin, Lutfu Hanoğlu, Erol Başar, Görsev Yener, Derya Durusu Emek-Savaş, Antonio Ivano Triggiani, Raffaella Franciotti, John Paul Taylor, Laura Vacca, Maria Francesca De Pandis, Laura Bonanni
Previous evidence showed abnormal posterior sources of resting-state delta (<4 Hz) and alpha (8–12 Hz) rhythms in patients with Alzheimer's disease with dementia (ADD), Parkinson's disease with dementia (PDD), and Lewy body dementia (DLB), as cortical neural synchronization markers in quiet wakefulness. Here, we tested the hypothesis of additional abnormalities in functional cortical connectivity computed in those sources, in ADD, considered as a "disconnection cortical syndrome", in comparison with PDD and DLB. Resting-state eyes-closed electroencephalographic (rsEEG) rhythms had been collected in 42 ADD, 42 PDD, 34 DLB, and 40 normal healthy older (Nold) participants. Exact low-resolution brain electromagnetic tomography (eLORETA) freeware estimated the functional lagged linear connectivity (LLC) from rsEEG cortical sources in delta, theta, alpha, beta, and gamma bands. The area under receiver operating characteristic (AUROC) curve indexed the classification accuracy between Nold and diseased individuals (only values >0.7 were considered). Interhemispheric and intrahemispheric LLCs in widespread delta sources were abnormally higher in the ADD group and, unexpectedly, normal in DLB and PDD groups. Intrahemispheric LLC was reduced in widespread alpha sources dramatically in ADD, markedly in DLB, and moderately in PDD group. Furthermore, the interhemispheric LLC in widespread alpha sources showed lower values in ADD and DLB than PDD groups. At the individual level, AUROC curves of LLC in alpha sources exhibited better classification accuracies for the discrimination of ADD versus Nold individuals (0.84) than for DLB versus Nold participants (0.78) and PDD versus Nold participants (0.75). Functional cortical connectivity markers in delta and alpha sources suggest a more compromised neurophysiological reserve in ADD than DLB, at both group and individual levels.
http://ift.tt/2FBsiux
Hypermetabolism in the hippocampal formation of cognitively impaired patients indicates detrimental maladaptation
Publication date: May 2018
Source:Neurobiology of Aging, Volume 65
Author(s): Ivayla Apostolova, Catharina Lange, Anja Mäurer, Per Suppa, Lothar Spies, Michel J. Grothe, Till Nierhaus, Jochen B. Fiebach, Elisabeth Steinhagen-Thiessen, R. Buchert
Structural deterioration and volume loss of the hippocampal formation is observed in many diseases associated with memory decline. Paradoxically, glucose metabolism of the hippocampal formation can be increased at the same time. This might be a consequence of compensatory (beneficial) or maladaptive (detrimental) mechanisms. Aim of this study was to differentiate between compensation and maladaptation by analyzing the association between glucose metabolism in the hippocampal formation measured by positron emission tomography with the glucose analogue 18F-fluorodeoxyglucose and cognitive performance as characterized by the extended Consortium to Establish a Registry for Alzheimer's Disease test battery in a sample of 87 patients (81.8 ± 5.4 years) with mild cognitive impairment or mild dementia and varying etiological diagnoses. Glucose metabolism in the hippocampal formation was negatively correlated with the performance in several cognitive subdomains, most pronounced for verbal semantic fluency, independent of overall neuronal dysfunction, presence of clinical Alzheimer's disease, and overall cognitive performance. This finding provides evidence that increased glucose metabolism in the hippocampal formation of cognitively impaired patients indicates detrimental maladaptation rather than a beneficial compensatory reaction. Excess glucose metabolism in the hippocampal formation might be a useful therapeutic target in these patients.
Graphical abstract
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Cerebral changes and disrupted gray matter cortical networks in asymptomatic older adults at risk for Alzheimer's disease
Source:Neurobiology of Aging, Volume 64
Author(s): Jose L. Cantero, Mercedes Atienza, Pascual Sanchez-Juan, Eloy Rodriguez-Rodriguez, Jose Luis Vazquez-Higuera, Ana Pozueta, Andrea Gonzalez-Suarez, Eduard Vilaplana, Jordi Pegueroles, Victor Montal, Rafael Blesa, Daniel Alcolea, Alberto Lleo, Juan Fortea
The diagnostic value of cerebrospinal fluid (CSF) biomarkers is well established in Alzheimer's disease, but our current knowledge about how abnormal CSF levels affect cerebral integrity, at local and network levels, is incomplete in asymptomatic older adults. Here, we have collected CSF samples and performed structural magnetic resonance imaging scans in cognitively normal elderly as part of a cross-sectional multicenter study (SIGNAL project). To identify group differences in cortical thickness, white matter volume, and properties of structural networks, participants were split into controls (N = 20), positive amyloid-β (Aβ1–42+) (N = 19), and positive phosphorylated tau (N = 18). The Aβ1–42+ group exhibited thickening of middle temporal regions, while positive phosphorylated tau individuals showed thinning in the superior parietal and orbitofrontal cortices. Subjects with abnormal CSF biomarkers further showed regional white matter atrophy and more segregated cortical networks, the Aβ1–42+ group showing heightened isolation of cingulate and temporal cortices. Collectively, these findings highlight the relevance of combining structural brain imaging and connectomics for in vivo tracking of Alzheimer's disease lesions in asymptomatic stages.
http://ift.tt/2DiV4ht
Age differences in neural correlates of feedback processing after economic decisions under risk
Source:Neurobiology of Aging, Volume 65
Author(s): Carina Fernandes, Rita Pasion, Ana R. Gonçalves, Fernando Ferreira-Santos, Fernando Barbosa, Isabel P. Martins, João Marques-Teixeira
This study examines age-related differences in behavioral responses to risk and in the neurophysiological correlates of feedback processing. Our sample was composed of younger, middle-aged, and older adults, who were asked to decide between 2 risky options, in the gain and loss domains, during an EEG recording. Results evidenced group-related differences in early and later stages of feedback processing, indexed by differences in the feedback-related negativity (FRN) and P3 amplitudes. Specifically, in the loss domain, younger adults showed higher FRN amplitudes after non-losses than after losses, whereas middle-aged and older adults had similar FRN amplitudes after both. In the gain domain, younger and middle-aged adults had higher P3 amplitudes after gains than after non-gains, whereas older adults had similar P3 amplitudes after both. Behaviorally, older adults had higher rates of risky decisions than younger adults in the loss domain, a result that was correlated with poorer performance in memory and executive functions. Our results suggest age-related differences in the outcome-related expectations, as well as in the affective relevance attributed to the outcomes, which may underlie the group differences found in risk-aversion.
http://ift.tt/2FtzigH
Aging African green monkeys manifest transcriptional, pathological, and cognitive hallmarks of human Alzheimer's disease
Source:Neurobiology of Aging, Volume 64
Author(s): Paige E. Cramer, Renee C. Gentzel, Keith Q. Tanis, Joshua Vardigan, Yi Wang, Brett Connolly, Philip Manfre, Kenneth Lodge, John J. Renger, Celina Zerbinatti, Jason M. Uslaner
While many preclinical models of Alzheimer's disease (AD) have been reported, none fully recapitulate the disease. In an effort to identify an appropriate preclinical disease model, we characterized age-related changes in 2 higher order species, the African green monkey (AGM) and the rhesus macaque. Gene expression profiles in the dorsolateral prefrontal cortex and the visual cortex showed age-related changes in AGMs that are strikingly reminiscent of AD, whereas aged rhesus were most similar to healthy elderly humans. Biochemically, age-related changes in AGM cerebrospinal fluid levels of tau, phospho-tau, and amyloid beta were consistent with AD. Histologically, aged AGMs displayed pathological hallmarks of the disease, plaques, and 2 AGMs showed evidence of neurofibrillary tangle-like structures. We hypothesized and confirmed that AGMs have age-related cognitive deficits via a prefrontal cortex-dependent cognition test, and that symptomatic treatments that improve cognition in AD patients show efficacy in AGMs. These data suggest that the AGM could represent a novel and improved translational model to assist in the development of therapeutics for AD.
http://ift.tt/2DhVVid
Neuroprotective effects of voluntary running on cognitive dysfunction in an α-synuclein rat model of Parkinson's disease
Source:Neurobiology of Aging, Volume 65
Author(s): Erin K. Crowley, Yvonne M. Nolan, Aideen M. Sullivan
Parkinson's disease (PD) is no longer primarily classified as a motor disorder due to increasing recognition of the impact on patients of several nonmotor PD symptoms, including cognitive dysfunction. These nonmotor symptoms are highly prevalent and greatly affect the quality of life of patients with PD, and so, therapeutic interventions to alleviate these symptoms are urgently needed. The aim of this study was to investigate the potential neuroprotective effects of voluntary running on cognitive dysfunction in an adeno-associated virus-α-synuclein rat model of PD. Bilateral intranigral administration of adeno-associated virus-α-synuclein was found to induce motor dysfunction and a significant loss of nigral dopaminergic neurons, neither of which were rescued by voluntary running. Overexpression of α-synuclein also resulted in significant impairment on hippocampal neurogenesis-dependent pattern separation, a cognitive task; this was rescued by voluntary running. This was substantiated by an effect of running on neurogenesis levels in the dorsal dentate gyrus, suggesting that the functional effects of running on pattern separation were mediated via increased neurogenesis.
http://ift.tt/2Ftz3lN
Early-life stress induces cognitive disorder in middle-aged mice
Source:Neurobiology of Aging, Volume 64
Author(s): Hiroyuki Yajima, Asahi Haijima, Miski Aghnia Khairinisa, Noriaki Shimokawa, Izuki Amano, Yusuke Takatsuru
Early-life stress can induce several neuropsychological disorders in adulthood. However, the underlying mechanisms inducing such disorders are still not fully understood. Furthermore, the effects of early-life stress on the changes in cognitive function with age are still not clarified. In this study, we used maternal deprivation (MD) to examine the cognitive function in middle-aged mice using a touchscreen-equipped operant chamber. In the visual-discrimination task, the aged (∼1.4 years old) control mice could accurately learn to discriminate between different visual stimuli. In contrast, the correct response rate of aged MD mice increased to ∼60% by day 10; it was still significantly lower than that of the control mice (85%). In the hippocampus of aged MD mice, the expression level of the N-methyl-d-aspartate receptor subunit GluN1 decreased significantly as compared to that in control mice. On the other hand, no significant difference in GluN1 expression level was detected in young (2.5 months old) mice. These findings indicate that early-life stress accelerates cognitive impairment in middle-aged mice.
http://ift.tt/2FyCK5S
Visual and visuomotor interhemispheric transfer time in older adults
Source:Neurobiology of Aging, Volume 65
Author(s): Brian Scally, Melanie Rose Burke, David Bunce, Jean-Francois Delvenne
Older adults typically experience reductions in the structural integrity of the anterior channels of the corpus callosum. Despite preserved structural integrity in central and posterior channels, many studies have reported that interhemispheric transfer, a function attributed to these regions, is detrimentally affected by aging. In this study, we use a constrained event-related potential analysis in the theta and alpha frequency bands to determine whether interhemispheric transfer is affected in older adults. The crossed-uncrossed difference and lateralized visual evoked potentials were used to assess interhemispheric transfer in young (18–27) and older adults (63–80). We observed no differences in the crossed-uncrossed difference measure between young and older groups. Older adults appeared to have elongated transfer in the theta band potentials, but this effect was driven by shortened contralateral peak latencies, rather than delayed ipsilateral latencies. In the alpha band, there was a trend toward quicker transfer in older adults. We conclude that older adults do not experience elongated interhemispheric transfer in the visuomotor or visual domains and that these functions are likely attributed to posterior sections of the corpus callosum, which are unaffected by aging.
http://ift.tt/2GiY5S1
Faster progression from MCI to probable AD for carriers of a single-nucleotide polymorphism associated with type 2 diabetes
Source:Neurobiology of Aging, Volume 64
Author(s): Hugo Girard, Olivier Potvin, Scott Nugent, Caroline Dallaire-Théroux, Stephen Cunnane, Simon Duchesne
Sporadic Alzheimer's disease (AD), as opposed to its autosomal dominant form, is likely caused by a complex interaction of genetic, environmental, and health lifestyle factors. Twin studies indicate that sporadic AD heritability could be between 58% and 79%, around half of which is explained by the ε4 allele of the apolipoprotein E (APOE4). We hypothesized that genes associated with known risk factors for AD, namely hypertension, hypercholesterolemia, obesity, diabetes, and cardiovascular disease, would contribute significantly to the remaining heritability. We analyzed 22 AD-associated single-nucleotide polymorphisms (SNPs), associated with these risk factors, that were included in the sequencing data of the Alzheimer's Disease Neuroimaging Initiative 1 data set, which included 355 participants with mild cognitive impairment (MCI). We built survival models with the selected SNPs to predict progression of MCI to probable AD over the 10-year follow-up of the study. The rs391300 SNP, located on the serine racemase (SRR) gene and linked to increased susceptibility to type 2 diabetes, was associated with progression from MCI to probable AD.
http://ift.tt/2DjMr6c
Neuroinflammation in Alzheimer’s disease: Pleiotropic roles for cytokines and neuronal pentraxins
Source:Behavioural Brain Research, Volume 347
Author(s): Ashley Swanson, Tovah Wolf, Alli Sitzmann, Auriel A. Willette
Neuroinflammation is a potential factor speculated to underlie Alzheimer's disease (AD) etiopathogenesis and progression. The overwhelming focus in this area of research to date has been on the chronic upregulation of pro-inflammatory cytokines to understand how neuroinflammatory mechanisms contribute to neurodegeneration. Yet, it is important to understand the pleiotropic roles of these cytokines in modulating neuroinflammation in which they cannot be labeled as a strictly "good" or "bad" biomarker phenotype. As such, biomarkers with more precise functions are needed to better understand how neuroinflammation impacts the brain in AD. Neuronal pentraxins are a concentration- dependent group of pro- or anti- inflammatory cytokines. There is contradictory evidence of these pentraxins as being both neuroprotective and potentially detrimental in AD. Potential neuroprotective examples include their ability to predict AD-related outcomes such as cognition, memory function and synaptic refinement. This review will briefly outline the basis of AD and subsequently summarize findings for neuropathological mechanisms of neuroinflammation, roles for traditional pro-and anti-inflammatory cytokines, and data found thus far on the neuronal pentraxins.
http://ift.tt/2GfAAcl
Extreme delta - with or without brushes: a potential surrogate marker of disease activity in anti-NMDA-receptor encephalitis
Source:Clinical Neurophysiology
Author(s): Claude Steriade, Stephen Hantus, Ahsan N.V. Moosa, Alexander D. Rae-Grant
ObjectiveAnti-NMDA receptor encephalitis (NMDARE) may not respond to first line immunotherapy. Biomarkers to track disease course and guide escalation of immunotherapy are needed. We describe the evolution of EEG in four patients with NMDARE requiring prolonged intensive care.MethodsWithin a database of 121 patients with immune-mediated neurological disorders, ten with NMDARE were retrospectively identified. Four patients did not respond to first line immunotherapy. Continuous EEG was reviewed and correlated with clinical status and treatment.ResultsIntermittent polymorphic delta slowing was present in all patients. Generalized rhythmic delta occupied increasing proportion of the EEG as disease progressed, at times with superimposed beta. The institution of second line immunotherapy was followed by progressive decrease in rhythmic delta, predating clinical improvement. In one patient who did not respond to second line immunotherapy, rhythmic delta continued to occupy a majority of the recording. The extreme delta pattern was not seen in a comparison cohort of patients with autoimmune encephalitis without anti-NMDA-R antibodies.ConclusionsExtreme delta, with or without brushes, increases with progression of NMDARE, responds to escalation of immunotherapy, predating clinical improvement, and is likely specific to NMDA-R antibodies.SignificanceExtreme delta may be a surrogate marker of disease activity in NMDARE refractory to first line immunotherapy.
http://ift.tt/2Fyjc1o
Long Term Electroencephalography in Preterm Neonates: Safety and Quality of Electrode Types
Source:Clinical Neurophysiology
Author(s): Nathalie M. El Ters, Amit M. Mathur, Siddharth Jain, Zachary A. Vesoulis, John M. Zempel
ObjectivesThe objective of this study was to compare gold cup and hydrogel electrodes for frequency of electrode replacement, longevity of the original electrodes after initial placement, recording quality, and skin safety issues in long-term EEG studies in preterm neonates.MethodsWe performed a prospective trial with newborns born at ≥23 weeks and ≤30 weeks of gestational age (GA). Two mirror image EEG electrode arrays were utilized on consecutive subjects, wheregold cup electrodes alternated with hydrogel electrodes.ResultsOur sample included 50 neonates with meanGA of 27 (±1) weeks. The mean recording time was 84 (±15) hours. No difference was present in the frequency of replacement of either type across the total recording time (p=0.8). We collected the time at which electrodes were first replaced, and found that hydrogel electrodes showed a longer uninterrupted recording time of 28(±2) hours vs. 20(±2) hours for gold cup electrodes (p=0.01). Recording quality was similar in either type (p=0.2). None of the patients experienced significant skin irritation from a discrete electrode.ConclusionLong-term EEG studies can be performed with either gold cup or hydrogel electrodes, validating the safety and quality of both electrode types.SignificanceHydrogel electrodes are a reasonable alternative for use in long-term EEG studies in preterm neonates.
http://ift.tt/2FGL32T
Κυριακή 11 Μαρτίου 2018
Successful therapy of ocular rosacea with topical ivermectin
Approximately 75% of cutaneous rosacea patients also suffer from an ocular involvement with blepharitis and meibomian gland dysfunction often presented as chalazia. Clinical symptoms are foreign body sensation, light sensitivity, burning and tearing.
This article is protected by copyright. All rights reserved.
http://ift.tt/2Hp3x50
FOSB immunoreactivity in endothelia of epithelioid hemangioma (angiolymphoid hyperplasia with eosinophilia)
Background
Accurate distinction of epithelioid hemangioma (EH) from its malignant mimics is paramount but it remains challenging due to its wide morphological spectrum and lack of objective molecular markers. FOSB oncogenic activation was recently identified as a key event in endothelial proliferation. We sought to investigate the FOSB staining pattern in EH with angiolymphoid hyperplasia with eosinophilia morphology (EH-AHLE) and to evaluate its value in differential diagnosis of epithelioid vascular tumors.
Methods
From the authors' files, 15 representative cases of EH-ALHE were selected and evaluated for their FOSB immunostaining pattern. Other vascular proliferations which can be morphological mimics were also tested: epithelioid hemangioendothelioma (EHE) (5 cases) and epithelioid angiosarcoma (EAS) (5 cases).
Results
All 15 cases of EH-ALHE showed strong and homogeneous FOSB nuclear positivity in endothelial cells with ample cytoplasm and intracytoplasmic vacuoles. All cases of EHE and EAS lacked FOSB immunoreactivity or showed only incidental weak FOSB immunoreactivity in less than 5 nuclei per lesion.
Conclusions
FOSB immunohistochemistry is sensitive in the diagnosis of EH-ALHE, and allows differentiation from its histological mimics. An immunohistochemical panel including not only pan-cytokeratin AE1/AE3 and endothelial markers, but also FOSB, helps in the diagnosis of epithelioid vascular tumors.
http://ift.tt/2tBShjD
HOX cluster-embedded micro-RNAs and cancer
Publication date: Available online 11 March 2018
Source:Biochimica et Biophysica Acta (BBA) - Reviews on Cancer
Author(s): Sebastian Fantini, Valentina Salsi, Vincenzo Zappavigna
http://ift.tt/2Fs8SvL
The MTT-formazan assay: Complementary technical approaches and in vivo validation in Drosophila larvae
Source:Acta Histochemica
Author(s): Raquel Pascua-Maestro, Miriam Corraliza-Gomez, Sergio Diez-Hermano, Candido Perez-Segurado, María D. Ganfornina, Diego Sanchez
The MTT assay was the first widely accepted method to assess cytotoxicity and cell viability. However, there is controversy on whether this indicator is a useful tool. In this work we intend to expand the interpretability of the MTT study by its combination with widely used cellular biology techniques. We propose complementary approaches to the colorimetric assay, based on the use of measurements in three different settings: confocal microscopy, multi-well plate assay and flow cytometry. Using confocal microscopy, we confirmed that MTT uptake and reduction by cells is a time-dependent process, and that formazan accumulates in round-shaped organelles. Quantitative measurements with a multi-well fluorimeter combined with nuclear staining result in a useful method, yielding a ratio between formazan production and cell number that informs about the average cell metabolic state. We also found that flow cytometry is a suitable technique to measure MTT reduction in large cell populations. When assaying the effect of an oxidizing agent such as paraquat (PQ), this approach allows for the distinction of subpopulations of cells with different reducing power. Finally, we prove that it is feasible to monitor MTT reduction in an in vivo model, the Drosophila larvae, without affecting its survival rate. Formazan accumulates exclusively in the larval fat body, confirming its lipid solubility. The methods explored in this work expand the MTT potential as a useful tool to provide information of the physiological state of cells and organisms.
http://ift.tt/2Fqv5dT
An immunohistochemical and ultrastructural analysis of the retina in tadalafil (Cialis) treated rats
Source:Acta Histochemica
Author(s): Nahla Reda Sarhan, Nesreen Moustafa Omar
Tadalafil (Cialis) is one of the most commonly used phosphodiesterase type5 (PDE5) inhibitors. This work aimed to analyze the histological and ultrastructural changes provoked by chronic tadalafil administration in the rat retina, correlate between such changes and PDE5 immunoexpression and to evaluate the possible reversibility of these changes. Thirty Sprague Dawley male rats were randomly distributed into 3 groups. Control group; given 1 ml distilled water daily for 6 weeks. Tadalafil group; given tadalafil in a daily dose of 2.6 mg/kg for 6 weeks. Withdrawal group; given tadalafil 2.6 mg/kg daily for 6 week followed by a withdrawal period of 4 weeks. Retinal specimens were prepared for histological, ultrastructural and immunohistochemical study using anti-PDE5 and anti-Bcl-2 antibodies. Morphometric and statistical studies were performed. Tadalafil group displayed a significant reduction in retinal thickness, diminished cell population of outer and inner nuclear layers, dilated blood capillaries and a significant decline in the number of ganglion cells. Significant reductions of both PDE5 and Bcl-2 immunoexpression were observed. At the ultrastructural level, the photoreceptors showed spacing of outer segments and disorganized membranous discs. Retinal neurons showed ultrastructural degenerative changes in the form of shrunken irregular nuclei, dilated rER, and disrupted mitochondria. Withdrawal group revealed preservation of histological structure and partial restoration of retinal thickness, retinal cells ultrastructure, and PDE5 and Bcl-2 immunoexpressions. In conclusion, chronic use of tadalafil could induce reversible apoptotic and degenerative changes in retinal neurons due to its inhibitory effect on PDE5 expression which affects the metabolism and viability of retinal cells.
http://ift.tt/2DjksDJ
A novel surgical technique for a rat subcutaneous implantation of a tissue engineered scaffold
Publication date: Available online 5 March 2018
Source:Acta Histochemica
Author(s): Reza Khorramirouz, Jason L. Go, Christopher Noble, Soumen Jana, Eva Maxson, Amir Lerman, Melissa D. Young
ObjectivesSubcutaneous implantations in small animal models are currently required for preclinical studies of acellular tissue to evaluate biocompatibility, including host recellularization and immunogenic reactivity.MethodsThree rat subcutaneous implantation methods were evaluated in six Sprague Dawley rats. An acellular xenograft made from porcine pericardium was used as the tissue-scaffold. Three implantation methods were performed; 1) Suture method is where a tissue-scaffold was implanted by suturing its border to the external oblique muscle, 2) Control method is where a tissue-scaffold was implanted without any suturing or support, 3) Frame method is where a tissue-scaffold was attached to a circular frame composed of polycaprolactone (PCL) biomaterial and placed subcutaneously. After 1 and 4 weeks, tissue-scaffolds were explanted and evaluated by hematoxylin and eosin (H&E), Masson's trichrome,Picrosirius Red, transmission electron microscopy (TEM), immunohistochemistry, and mechanical testing.ResultsMacroscopically, tissue-scaffold degradation with the suture method and tissue-scaffold folding with the control method were observed after 4 weeks. In comparison, the frame method demonstrated intact tissue scaffolds after 4 weeks. H&E staining showed progressive cell repopulation over the course of the experiment in all groups with acute and chronic inflammation observed in suture and control methods throughout the duration of the study. Immunohistochemistry quantification of CD3, CD 31, CD 34, CD 163, and αSMA showed a statistically significant differences between the suture, control and frame methods (P < 0.05) at both time points. The average tensile strength was 4.03 ± 0.49, 7.45 ± 0.49 and 5.72 ± 1.34 (MPa) after 1 week and 0.55 ± 0.26, 0.12 ± 0.03 and 0.41 ± 0.32 (MPa) after 4 weeks in the suture, control, and frame methods; respectively. TEM analysis showed an increase in inflammatory cells in both suture and control methods following implantation.ConclusionRat subcutaneous implantation with the frame method was performed with success and ease. The surgical approach used for the frame technique was found to be the best methodology for in vivo evaluation of tissue engineered acellular scaffolds, where the frame method did not compromise mechanical strength, but it reduced inflammation significantly.
http://ift.tt/2FsPHCn
Synergistic anti-proliferative effects of mTOR and MEK inhibitors in high-grade chondrosarcoma cell line OUMS-27
Source:Acta Histochemica, Volume 120, Issue 2
Author(s): Singo Fukumoto, Kiyoto Kanbara, Masashi Neo
Chondrosarcoma is a malignant bone tumor that produces cartilaginous neoplastic tissue. Owing to the absence of an effective adjuvant therapy, high-grade chondrosarcoma has a poor prognosis. Therefore, it is important to develop an effective adjuvant therapy to prevent the recurrence and metastasis. Mammalian target of rapamycin (mTOR), a central regulator of cell growth, metabolism, proliferation, and survival, is considered an important target for anticancer drug development. The mitogen activated protein kinase (MAPK) pathway is another highly implicated cellular pathway in cancer and is thought to have compensatory effects in response to the inhibition of the phosphatidylinositol-3-kinase (PI3K)/Akt/mTOR signaling pathway. We investigated the mechanism of anti-proliferative effect of the mTOR inhibitor rapamycin and MAPK/ERK (MEK) inhibitor PD 0325901, and the combined effect of rapamycin and PD 0325901 on human chondrosarcoma cell line (OUMS-27). Combination therapy with rapamycin and PD 0325901 showed a stronger anti-proliferative effect on OUMS-27 cells than rapamycin monotherapy. We confirmed that the dual inhibition of the PI3K/Akt/mTOR and RAF/MEK/ERK signaling pathways had synergistic anti-proliferative effects in OUMS-27. Our results suggest that combination therapy of mTOR and MEK inhibitor could be an effective therapeutic approach against chondrosarcoma.
http://ift.tt/2FyafoP
Tetrazolium salts and formazan products in Cell Biology: Viability assessment, fluorescence imaging, and labeling perspectives
Source:Acta Histochemica
Author(s): Juan C. Stockert, Richard W. Horobin, Lucas L. Colombo, Alfonso Blázquez-Castro
For many years various tetrazolium salts and their formazan products have been employed in histochemistry and for assessing cell viability. For the latter application, the most widely used are 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), and 5-cyano-2,3-di-(p-tolyl)-tetrazolium chloride (CTC) for viability assays of eukaryotic cells and bacteria, respectively. In these cases, the nicotinamide-adenine-dinucleotide (NAD(P)H) coenzyme and dehydrogenases from metabolically active cells reduce tetrazolium salts to strongly colored and lipophilic formazan products, which are then quantified by absorbance (MTT) or fluorescence (CTC). More recently, certain sulfonated tetrazolium, which give rise to water-soluble formazans, have also proved useful for cytotoxicity assays. We describe several aspects of the application of tetrazolium salts and formazans in biomedical cell biology research, mainly regarding formazan-based colorimetric assays, cellular reduction of MTT, and localization and fluorescence of the MTT formazan in lipidic cell structures. In addition, some pharmacological and labeling perspectives of these compounds are also described.
http://ift.tt/2GhPDm1
Localization of EFA6 (exchange factor for ARF6) isoform D in steroidogenic testicular Leydig cells of adult mice
Source:Acta Histochemica
Author(s): Surang Chomphoo, Sawetree Pakkarato, Tarinee Sawatpanich, Hiroyuki Sakagami, Hisatake Kondo, Wiphawi Hipkaeo
EFA6 (exchange factor for ARF6) activates Arf6 (ADP ribosylation factor 6) by exchanging ADP to ATP and the resulting activated form of Arf6 is involved in the membrane trafficking and actin remodeling of cells. Our previous study has shown the selective expression/localization of EFA6D in steroidogenic adrenocortical cells in situ of adult mice. In view of the previous finding, the present study was undertaken to examine its localization in mouse Leydig cells representing another steroidogenic cell species in order to further support the possible involvement of the EFA6/Arf6 cascade via membrane trafficking in the regulation of steroidogenesis and/or secretion. A distinct band for EFA6D with the same size as that of the brain was detected in the testis of adult mice. In immuno-light microscopy, immunoreactivity for EFA6D was seen throughout the cytoplasm in most Leydig cells without any distinct accumulation along the plasmalemma. Lack of immunoreactivity for EFA6D was seen in the seminiferous tubular epithelium. In immuno-electron microscopy, the immune-labeling was seen in sporadic/focal patterns on plasma membranes and some vesicles and vacuoles subjacent to the plasma membranes. More constant and rather predominant is the labeling on numerous mitochondria. No immuno-labeling was seen in lipid droplets. The present study suggests that EFA6D is somehow involved in regulation of the synthesis and/or secretion of testosterone through the membrane-traffic by activation of Arf6. In addition, EFA6D is suggested to play in mitochondria some yet unidentified roles rather independent of Arf6-activation, which remains to be elucidated.
http://ift.tt/2DkCq8W
Evaluating the effect of three newly approved overactive bladder syndrome treating agents on parotid and submandibular salivary glands: Modulation of CXCL10 expression
Source:Acta Histochemica
Author(s): Basma Emad Aboulhoda, Eid Nassar Ali
BackgroundDespite enormous progresses in understanding pathophysiology of the lower urinary tract, antimuscarinics remain the chief clinically well-established approach for improving symptoms of overactive bladder (OAB). Dry mouth on the other hand remains one of the most untolerated systemic side effects of these drugs that limits their uses and results in high discontinuation rate. Three novel drugs have been recently approved by US Food and Drug Administration for treatment of OAB: trospium, darifenacin, and solifenacin.AimsThis study has been conducted to provide clear head to head comparative studying of histological and ultrastructural effect of those newly emerging drugs on parotid and submandibular salivary glands and to demonstrate the differential expression of CXCL10 to make a cogent structural and molecular assessment of the relative tolerability of these drugs and the potential mechanisms of occurrence of dry mouth.MethodsFifty male Sprague Dawley rats were equally divided into five groups: Group I (control), Group II (oxybutynin-treated), Group III (trospium-treated), Group IV (darifenacin-treated) and Group V (solifenacin-treated). Histological and ultrastructural studies were performed on parotid and submandibular glands. Measurement of salivary flow, PCR analysis and immunohistochemical assessment of CXCL10 expression have been carried-out.ResultsMuscarinic receptor antagonists led to various histological, morphometric and ultrastructural changes together with diminished salivary secretion and up-regulation of CXCL10 expression with the mildest alterations observed with solifenacin.ConclusionsSolifenacin has shown the least adverse effects to salivary glands. CXCL10 is involved in degenerative changes of salivary glands induced by muscarinic antagonists.
http://ift.tt/2Fu04FY
Immunohistochemical localization of osteoblast activating peptide in the mouse kidney
Source:Acta Histochemica
Author(s): Ahmed E. Noreldin, Yaser Hosny Ali Elewa, Yasuhiro Kon, Katsuhiko Warita, Yoshinao Z. Hosaka
Osteoblast activating peptide (OBAP) is a newly discovered peptide detected in the rat stomach, which has a major role in osteogenesis. Recently, we revealed its localization in the parietal cells of the rat stomach. There have been no data regarding OBAP expression in the kidney, despite its role in calcium reabsorption in renal tubules. The current study aimed to inspect the expression of OBAP in the kidney of twelve 10-week-old male C3H/HeNJc1 mice using immunohistochemistry, and immunoelectron microscopic localization. The immunohistochemical investigation revealed an OBAP positive reaction mainly in the medulla, which was stronger than the cortex of the kidney and was concentrated in the distal convoluted tubules (DCT), connecting tubules (CT), and the thick limbs of the loop of Henle (HL). Moreover, we clarified that the OBAP was co-distributed with ghrelin and calbindin (markers of the DCT). Interestingly, immunoelectron microscopy demonstrated that OBAP was concentrated in the mitochondrial inner membrane of the DCT and CT. Based on these results, it was concluded that the mitochondria of the DCT, CT, and HL of the mice kidney generate OBAP. Furthermore, our results suggest that OBAP might have a role in the regulation of calcium reabsorption by the renal tubule; however, further investigations are required to clarify this potential role.
http://ift.tt/2FzcIiS
Localization of orexin B and orexin-2 receptor in the rat epididymis
Publication date: Available online 26 February 2018
Source:Acta Histochemica
Author(s): Giovanna Liguori, Simona Tafuri, Chika Miyoshi, Masashi Yanagisawa, Caterina Squillacioti, Valeria De Pasquale, Nicola Mirabella, Alfredo Vittoria, Anna Costagliola
The peptides orexin A (OXA) and orexin B (OXB) derived from the proteolytic cleavage of a common precursor molecule, prepro-orexin, were originally described in the rat hypothalamus. Successively, they have been found in many other brain regions as well as in peripheral organs of mammals and other less evolved animals. The widespread localization of orexins accounts for the multiple activities that they exert in the body, including the regulation of energy homeostasis, feeding, metabolism, sleep and arousal, stress, addiction, and cardiovascular and endocrine functions. Both OXA and OXB peptides bind to two G-coupled receptors, orexin-1 (OX1R) and orexin-2 (OX2R) receptor, though with different binding affinity. Altered expression/activity of orexins and their receptors has been associated with a large number of human diseases. Though at present evidence highlighted a role for orexins and cognate receptors in mammalian reproduction, their central and/or local effects on gonadal functions remain poorly known. Here, we investigated the localization of OXB and OX2R in the rat epididymis. Immunohistochemical staining of sections from caput, corpus and cauda segments of the organ showed intense signals for both OXB and OX2R in the principal cells of the lining epithelium, while no staining was detected in the other cell types. Negative results were obtained from immunohistochemical analysis of hypothalamic and testicular tissues from OX2R knock-out mice (OX2R−/−) and OX1R/OX2R double knock-out (OX1R−/−; OX2R−/−) mice, thus demonstrating the specificity of the rabbit polyclonal anti-OX2R antibody used in our study. On contrary, the same antibody clearly showed the presence of OX2R in sections from hypothalamus and testis of normal mice and rats which are well known to express the receptor. Thus, our results provide the first definite evidence for the immunohistochemical localization of OXB and OX2R in the principal cells of rat epididymis.
http://ift.tt/2FuWpb2
Immunohistochemical localization of angiotensin AT1 receptors in the rat carotid body
Source:Acta Histochemica, Volume 120, Issue 2
Author(s): Dimitrinka Y. Atanasova, Angel D. Dandov, Nikolay D. Dimitrov, Nikolai E. Lazarov
The carotid body (CB) is a major peripheral arterial chemoreceptor that initiates respiratory and cardiovascular adjustments to maintain homeostasis. Recent evidence suggests that circulating or locally produced hormones like angiotensin II acting via AT1 receptors modulate its activity in a paracrine-autocrine manner. The aim of this study was to examine the immunohistochemical localization of AT1 receptor in the CB of adult rats and to compare its expression in vehicle-treated animals, and after the long-term application of its selective blocker losartan. Immunohistochemistry revealed that a subset of CB glomeruli and the vast majority of neurons in the adjacent superior cervical ganglion (SCG) were strongly AT1 receptor-immunoreactive. In the CB immunostaining was observed in the chemosensory glomus cells typically aggregated in cell clusters while the nerve fibers in-between and large capillaries around them were immunonegative. Exogenous administration of losartan for a prolonged time significantly reduces the intensity of AT1 receptor immunostaining in the CB glomus cells and SCG neurons. Our results show that AT1 receptors are largely expressed in the rat CB under physiological conditions, and their expression is down-regulated by losartan treatment.
http://ift.tt/2DkChCq
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Publication date: September 2017 Source: Free Radical Biology and Medicine, Volume 110 Author(s): Lucía Fernández-del-Río, Anish Nag, Elen...
