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71.
Gupta Achla Gullapalli Srinivas Pan Hui Ramos-Ortolaza Dinah L. Hayward Michael D. Low Malcom J. Pintar John E. Devi Lakshmi A. Gomes Ivone 《Cellular and molecular neurobiology》2021,41(5):1103-1118
Cellular and Molecular Neurobiology - Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses.... 相似文献
72.
There is now considerable evidence that climate change is disrupting the phenology of key pollinator species. The recently reported UK winter activity of the bumblebee Bombus terrestris brings a novel set of thermal challenges to bumblebee workers that would typically only be exposed to summer conditions. Here we assess the ability of workers to survive acute and chronic cold stress (via lower lethal temperatures and lower lethal times at 0°C), the capacity for rapid cold hardening (RCH) and the influence of diet (pollen versus nectar consumption) on supercooling points (SCP). Comparisons are made with chronic cold stress indices and SCPs in queen bumblebees. Results showed worker bees were able to survive acute temperatures likely to be experienced in a mild winter, with queens significantly more tolerant to chronic cold temperature stress. The first evidence of RCH in any Hymenoptera is shown. In addition, dietary manipulation indicated the consumption of pollen significantly increased SCP temperature. These results are discussed in the light of winter active bumblebees and climate change. 相似文献
73.
Prashant G. Bhat Ajay M. V. Kumar Balaji Naik Srinath Satyanarayana Deepak KG Sreenivas A. Nair Suryakanth MD Einar Heldal Donald A. Enarson Anthony J. Reid 《PloS one》2013,8(12)
Background
Severe acute malnutrition (SAM) is the most serious form of malnutrition affecting children under-five and is associated with many infectious diseases including Tuberculosis (TB). In India, nutritional rehabilitation centres (NRCs) have been recently established for the management of SAM including TB. The National TB Programme (NTP) in India has introduced a revised algorithm for diagnosing paediatric TB. We aimed to examine whether NRCs adhered to these guidelines in diagnosing TB among SAM children.Methods
A cross-sectional study involving review of records of all SAM children identified by health workers during 2012 in six tehsils (sub-districts) with NRCs (population: 1.8 million) of Karnataka, India.Results
Of 1927 identified SAM children, 1632 (85%) reached NRCs. Of them, 1173 (72%) were evaluated for TB and 19(2%) were diagnosed as TB. Of 1173, diagnostic algorithm was followed in 460 (37%). Among remaining 763 not evaluated as per algorithm, tuberculin skin test alone was conducted in 307 (41%), chest radiography alone in 99 (13%) and no investigations in 337 (45%). The yield of TB was higher among children evaluated as per algorithm (4%) as compared to those who were not (0.3%) (OR: 15.3 [95%CI: 3.5-66.3]). Several operational challenges including non-availability of a full-time paediatrician, non-functioning X-ray machine due to frequent power cuts, use of tuberculin with suboptimal strength and difficulties in adhering to a complex diagnostic algorithm were observed.Conclusion
This study showed that TB screening in NRCs was sub-optimal in Karnataka. Some children did not reach the NRC, while many of those who did were either not or sub-optimally evaluated for TB. This study pointed to a number of operational issues that need to be addressed if this collaborative strategy is to identify more TB cases amongst malnourished children in India. 相似文献74.
Esmarie Jooste Matt W. Hayward Ross T. Pitman Lourens H. Swanepoel 《European Journal of Wildlife Research》2013,59(4):487-494
The ability to determine the prey-specific biomass intake of large predators is fundamental to their conservation. In the absence of actual prey data, researchers generally use a “unit mass” method (estimated as 3/4 adult female mass) to calculate the biomass intake of predators. However, differences in prey preference and range across geographic regions are likely to have an influence on biomass calculations. Here we investigate the influence of estimated prey mass on leopard biomass calculations, and subsequent carrying capacity estimates, in an understudied mountain population. Potential leopard feeding sites were identified using global positioning system (GPS) location clusters obtained from GPS collars. We investigated 200 potential leopard feeding sites, of which 96 were actual feeding sites. Jaw bones, horns, hooves, and other indicative bones were used to determine gender and age of prey items, which were subsequently used to calculate mass of each prey item based on previously published values. There were significant differences in the biomass values calculated using the traditional unit mass method and the calculated prey masses obtained from leopard feeding sites. However, there were no considerable differences in the carrying capacity estimates using the preferred prey species model and leopard density estimates calculated using a non-biased spatial approach, which suggests that estimating carnivore carrying capacity based on 3/4 adult female masses is a reliable method also for the mountain population in this study. 相似文献
75.
Allison Jones Andrew E. Teschendorff Quanxi Li Jane D. Hayward Athilakshmi Kannan Tim Mould James West Michal Zikan David Cibula Heidi Fiegl Shih-Han Lee Elisabeth Wik Richard Hadwin Rupali Arora Charlotte Lemech Henna Turunen P?ivi Pakarinen Ian J. Jacobs Helga B. Salvesen Milan K. Bagchi Indrani C. Bagchi Martin Widschwendter 《PLoS medicine》2013,10(11)
76.
Adam Auton Ying Rui Li Jeffrey Kidd Kyle Oliveira Julie Nadel J. Kim Holloway Jessica J. Hayward Paula E. Cohen John M. Greally Jun Wang Carlos D. Bustamante Adam R. Boyko 《PLoS genetics》2013,9(12)
The identification of the H3K4 trimethylase, PRDM9, as the gene responsible for recombination hotspot localization has provided considerable insight into the mechanisms by which recombination is initiated in mammals. However, uniquely amongst mammals, canids appear to lack a functional version of PRDM9 and may therefore provide a model for understanding recombination that occurs in the absence of PRDM9, and thus how PRDM9 functions to shape the recombination landscape. We have constructed a fine-scale genetic map from patterns of linkage disequilibrium assessed using high-throughput sequence data from 51 free-ranging dogs, Canis lupus familiaris. While broad-scale properties of recombination appear similar to other mammalian species, our fine-scale estimates indicate that canine highly elevated recombination rates are observed in the vicinity of CpG rich regions including gene promoter regions, but show little association with H3K4 trimethylation marks identified in spermatocytes. By comparison to genomic data from the Andean fox, Lycalopex culpaeus, we show that biased gene conversion is a plausible mechanism by which the high CpG content of the dog genome could have occurred. 相似文献
77.
Zahid MD Khurshidul Rogowski Michael Ponce Christopher Choudhury Mahua Moustaid-Moussa Naima Rahman Shaikh M. 《Molecular and cellular biochemistry》2020,463(1-2):211-223
Molecular and Cellular Biochemistry - Atherosclerosis is associated with deregulated cholesterol metabolism and formation of macrophage foam cells. CCAAT/enhancer-binding protein beta (C/EBPβ)... 相似文献
78.
Mandana Namayandeh MSc Marzieh Jamalidoust PhD Nahid Heydari Marandi MSc Nasrin Aliabadi PhD student Atoosa Ziyaeyan MASc student Gholamreza Pouladfar MD Mazyar Ziyaeyan PhD 《Microbiology and immunology》2020,64(11):762-767
Hepatitis C is a liver disease caused by the hepatitis C virus (HCV). The treatment of HCV infection has become more complicated due to various genotypes and subtypes of HCV. The treatment of HCV has made significant advances with direct-acting antivirals. However, for the choice of medicine or the combination of drugs for hepatitis C, it is imperative to detect and discriminate the crucial HCV genotypes. The main objective of this study was to determine the pattern of circulating HCV genotypes in southern Iran, from 2016 until 2019. The other aim of the study was to determine possible associations of patients’ risk factors with HCV genotypes. A total of 803 serum samples were collected in 4 years (2016–2019) from patients with HCV antibody positive results. A total of 728 serum samples were HCV-RNA positive. The prevalence of HCV genotypes was detected using the genotype-specific RT-PCR test for serum samples obtained from 615 patients. The HCV genotype 1 (G1) was the most prevalent (48.8%) genotype in the area, with G1a, G1b, and mixed G1a/b representing 38.4%, 10.1%, and 0.3%, respectively. Genotype 3a was the next most prevalent (47.2%). Mixed genotypes 1a/3a were detected in 22 (3.6%) and finally G4 was found in 3 (0.5%) patients. The other HCV genotypes were not detected in any patient. Genotype 1 (1a and 1b alone, 1a/1b and 1a/3a coinfections) is the most prevalent HCV genotype in southern Iran. HCV G1 shows a significantly higher rate in people under 40 years old. 相似文献
79.
80.
Jing Zhou MD Pengfei Wu MM Hongyu Sun MM Hong Zhou BM Yaolei Zhang BM Zhenliang Xiao MD 《Journal of cellular physiology》2020,235(3):2377-2388
This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage. 相似文献