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331.
Mourad W. Gabriel Leslie W. Woods Greta M. Wengert Nicole Stephenson J. Mark Higley Craig Thompson Sean M. Matthews Rick A. Sweitzer Kathryn Purcell Reginald H. Barrett Stefan M. Keller Patricia Gaffney Megan Jones Robert Poppenga Janet E. Foley Richard N. Brown Deana L. Clifford Benjamin N. Sacks 《PloS one》2015,10(11)
Wildlife populations of conservation concern are limited in distribution, population size and persistence by various factors, including mortality. The fisher (Pekania pennanti), a North American mid-sized carnivore whose range in the western Pacific United States has retracted considerably in the past century, was proposed for threatened status protection in late 2014 under the United States Endangered Species Act by the United States Fish and Wildlife Service in its West Coast Distinct Population Segment. We investigated mortality in 167 fishers from two genetically and geographically distinct sub-populations in California within this West Coast Distinct Population Segment using a combination of gross necropsy, histology, toxicology and molecular methods. Overall, predation (70%), natural disease (16%), toxicant poisoning (10%) and, less commonly, vehicular strike (2%) and other anthropogenic causes (2%) were causes of mortality observed. We documented both an increase in mortality to (57% increase) and exposure (6%) from pesticides in fishers in just the past three years, highlighting further that toxicants from marijuana cultivation still pose a threat. Additionally, exposure to multiple rodenticides significantly increased the likelihood of mortality from rodenticide poisoning. Poisoning was significantly more common in male than female fishers and was 7 times more likely than disease to kill males. Based on necropsy findings, suspected causes of mortality based on field evidence alone tended to underestimate the frequency of disease-related mortalities. This study is the first comprehensive investigation of mortality causes of fishers and provides essential information to assist in the conservation of this species. 相似文献
332.
Jodi J. L. Rowley Dao T. A. Tran Greta J. Frankham Anthony H. Dekker Duong T. T. Le Truong Q. Nguyen Vinh Q. Dau Huy D. Hoang 《PloS one》2015,10(5)
A major obstacle in prioritizing species or habitats for conservation is the degree of unrecognized diversity hidden within complexes of morphologically similar, “cryptic” species. Given that amphibians are one of the most threatened groups of organisms on the planet, our inability to diagnose their true diversity is likely to have significant conservation consequences. This is particularly true in areas undergoing rapid deforestation, such as Southeast Asia. The Southeast Asian genus Leptolalax is a group of small-bodied, morphologically conserved frogs that inhabit the forest-floor. We examined a particularly small-bodied and morphologically conserved subset, the Leptolalax applebyi group, using a combination of molecular, morphometric, and acoustic data to identify previously unknown diversity within. In order to predict the geographic distribution of the group, estimate the effects of habitat loss and assess the degree of habitat protection, we used our locality data to perform ecological niche modelling using MaxEnt. Molecular (mtDNA and nuDNA), acoustic and subtle morphometric differences revealed a significant underestimation of diversity in the L. applebyi group; at least two-thirds of the diversity may be unrecognised. Patterns of diversification and microendemism in the group appear driven by limited dispersal, likely due to their small body size, with several lineages restricted to watershed basins. The L. applebyi group is predicted to have historically occurred over a large area of the Central Highlands of Vietnam, a considerable portion of which has already been deforested. Less than a quarter of the remaining forest predicted to be suitable for the group falls within current protected areas. The predicted distribution of the L. applebyi group extends into unsurveyed watershed basins, each potentially containing unsampled diversity, some of which may have already been lost due to deforestation. Current estimates of amphibian diversity based on morphology alone are misleading, and accurate alpha taxonomy is essential to accurately prioritize conservation efforts. 相似文献
333.
Frida F?k Greta Jakobsdottir Evelina Kulcinskaja Nittaya Marungruang Chrysoula Matziouridou Ulf Nilsson Henrik St?lbrand Margareta Nyman 《PloS one》2015,10(5)
The aim of this study was to investigate how physico-chemical properties of two dietary fibres, guar gum and pectin, affected weight gain, adiposity, lipid metabolism, short-chain fatty acid (SCFA) profiles and the gut microbiota in male Wistar rats fed either low- or high-fat diets for three weeks. Both pectin and guar gum reduced weight gain, adiposity, liver fat and blood glucose levels in rats fed a high-fat diet. Methoxylation degree of pectin (low, LM and high (HM)) and viscosity of guar gum (low, medium or high) resulted in different effects in the rats, where total blood and caecal amounts of SCFA were increased with guar gum (all viscosities) and with high methoxylated (HM) pectin. However, only guar gum with medium and high viscosity increased the levels of butyric acid in caecum and blood. Both pectin and guar gum reduced cholesterol, liver steatosis and blood glucose levels, but to varying extent depending on the degree of methoxylation and viscosity of the fibres. The medium viscosity guar gum was the most effective preparation for prevention of diet-induced hyperlipidaemia and liver steatosis. Caecal abundance of Akkermansia was increased with high-fat feeding and with HM pectin and guar gum of all viscosities tested. Moreover, guar gum had distinct bifidogenic effects independent of viscosity, increasing the caecal abundance of Bifidobacterium ten-fold. In conclusion, by tailoring the viscosity and possibly also the degree of methoxylation of dietary fibre, metabolic effects may be optimized, through a targeted modulation of the gut microbiota and its metabolites. 相似文献
334.
Greta S. Aeby Thierry M. Work Christina M. Runyon Amanda Shore-Maggio Blake Ushijima Patrick Videau Silvia Beurmann Sean M. Callahan 《PloS one》2015,10(3)
A high number of coral colonies, Montipora spp., with progressive tissue loss were reported from the north shore of Kaua‘i by a member of the Eyes of the Reef volunteer reporting network. The disease has a distinct lesion (semi-circular pattern of tissue loss with an adjacent dark band) that was first observed in Hanalei Bay, Kaua‘i in 2004. The disease, initially termed Montipora banded tissue loss, appeared grossly similar to black band disease (BBD), which affects corals worldwide. Following the initial report, a rapid response was initiated as outlined in Hawai‘i’s rapid response contingency plan to determine outbreak status and investigate the disease. Our study identified the three dominant bacterial constituents indicative of BBD (filamentous cyanobacteria, sulfate-reducing bacteria, sulfide-oxidizing bacteria) in coral disease lesions from Kaua‘i, which provided the first evidence of BBD in the Hawaiian archipelago. A rapid survey at the alleged outbreak site found disease to affect 6-7% of the montiporids, which is higher than a prior prevalence of less than 1% measured on Kaua‘i in 2004, indicative of an epizootic. Tagged colonies with BBD had an average rate of tissue loss of 5.7 cm2/day over a two-month period. Treatment of diseased colonies with a double band of marine epoxy, mixed with chlorine powder, effectively reduced colony mortality. Within two months, treated colonies lost an average of 30% less tissue compared to untreated controls. 相似文献
335.
Resolving the conundrum of inbreeding depression but no inbreeding avoidance: Estimating sex‐specific selection on inbreeding by song sparrows (Melospiza melodia)
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Jane M. Reid Peter Arcese Greta Bocedi A. Bradley Duthie Matthew E. Wolak Lukas F. Keller 《Evolution; international journal of organic evolution》2015,69(11):2846-2861
Inbreeding avoidance among interacting females and males is not always observed despite inbreeding depression in offspring fitness, creating an apparent “inbreeding paradox.” This paradox could be resolved if selection against inbreeding was in fact weak, despite inbreeding depression. However, the net magnitude and direction of selection on the degree to which females and males inbreed by pairing with relatives has not been explicitly estimated. We used long‐term pedigree data to estimate phenotypic selection gradients on the degree of inbreeding that female and male song sparrows (Melospiza melodia) expressed by forming socially persistent breeding pairs with relatives. Fitness was measured as the total numbers of offspring and grand offspring contributed to the population, and as corresponding expected numbers of identical‐by‐descent allele copies, thereby accounting for variation in offspring survival, reproduction, and relatedness associated with variation in parental inbreeding. Estimated selection gradients on the degree to which individuals paired with relatives were weakly positive in females, but negative in males that formed at least one socially persistent pairing. However, males that paired had higher mean fitness than males that remained socially unpaired. These analyses suggest that net selection against inbreeding may be weak in both sexes despite strong inbreeding depression, thereby resolving the “inbreeding paradox.” 相似文献
336.
Microparticles (MPs) are small membrane vesicles released by stimulated or apoptotic cells, including the endothelium. Hyperhomocysteinemia
(HHcy) is a blood disorder characterized by an increase in the plasma concentrations of total homocysteine (Hcy). The plasma
Hcy level is determined by environmental factors (dietary habits, i.e. the intake of folic acid, FA) and genetic factors (N
5,N
10-methylenetetrahydro-folate reductase, MTHFR, polymorphism 677C>T). To evaluate whether moderate Hcy concentrations induce
endothelial MP formation, the role of FA supplementation and the influence of MTHFR polymorphism were analysed. Human umbilical
vein endothelial cells (HUVEC) were treated in vitro with 50 μM of Hcy and methionine (Met). The MP number and apoptotic phenotype were analyzed using flow cytometry. Increasing
doses of FA (5, 15 and 50 μM) were used to reduce the HHcy effect. The MTHFR 677C>T polymorphism was determined. HUVEC stimulated
by Hcy produced significantly more MPs than HUVEC under the control conditions: 3,551 ± 620 vs 2,270 ± 657 kMP (p = 0.02).
Supplementation with FA at concentrations of 5, 15 and 50 μM reduced the MP count in the cell culture supernatant to 345 ±
332, 873 ± 329, and 688 ± 453 kMP, respectively (p = 0.03). MTHFR 677C>T heterozygosity was associated with a significant
increase in MP formation after stimulation with Hcy compared to the control conditions: 3,617 ± 152 vs 1,518 ± 343 kMP (p
= 0.02). Furthermore, the MTHFR genotype altered MP formation after Met loading. On average, 24% of the entire MP population
was apoptotic (annexin V-positive). Endothelial function impairment due to HHcy is related to MP shedding, which may involve
platelets and other blood and vascular cells. MP shedding is a physiological response to moderate HHcy. 相似文献
337.
Differential expression of NLRP3 among hematopoietic cells 总被引:1,自引:0,他引:1
Guarda G Zenger M Yazdi AS Schroder K Ferrero I Menu P Tardivel A Mattmann C Tschopp J 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(4):2529-2534
Although the importance of the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome in health and disease is well appreciated, a precise characterization of NLRP3 expression is yet undetermined. To this purpose, we generated a knock-in mouse in which the Nlrp3 coding sequence was substituted for the GFP (enhanced GFP [egfp]) gene. In this way, the expression of eGFP is driven by the endogenous regulatory elements of the Nlrp3 gene. In this study, we show that eGFP expression indeed mirrors that of NLRP3. Interestingly, splenic neutrophils, macrophages, and, in particular, monocytes and conventional dendritic cells showed robust eGFP fluorescence, whereas lymphoid subsets, eosinophils, and plasmacytoid dendritic cells showed negligible eGFP levels. NLRP3 expression was highly inducible in macrophages, both by MyD88- and Trif-dependent pathways. In vivo, when mice were challenged with diverse inflammatory stimuli, differences in both the number of eGFP-expressing cells and fluorescence intensity were observed in the draining lymph node. Thus, NLRP3 levels at the site of adaptive response initiation are controlled by recruitment of NLRP3-expressing cells and by NLRP3 induction. 相似文献
338.
Ebel GD Fitzpatrick KA Lim PY Bennett CJ Deardorff ER Jerzak GV Kramer LD Zhou Y Shi PY Bernard KA 《Journal of virology》2011,85(23):12605-12613
West Nile virus (WNV) is similar to other RNA viruses in that it forms genetically complex populations within hosts. The virus is maintained in nature in mosquitoes and birds, with each host type exerting distinct influences on virus populations. We previously observed that prolonged replication in mosquitoes led to increases in WNV genetic diversity and diminished pathogenesis in mice without remarkable changes to the consensus genome sequence. We therefore sought to evaluate the relationships between individual and group phenotypes in WNV and to discover novel viral determinants of pathogenesis in mice and fitness in mosquitoes and birds. Individual plaque size variants were isolated from a genetically complex population, and mutations conferring a small-plaque and mouse-attenuated phenotype were localized to the RNA helicase domain of the NS3 protein by reverse genetics. The mutation, an Asp deletion, did not alter type I interferon production in the host but rendered mutant viruses more susceptible to interferon compared to wild type (WT) WNV. Finally, we used an in vivo fitness assay in Culex quinquefasciatus mosquitoes and chickens to determine whether the mutation in NS3 influenced fitness. The fitness of the NS3 mutant was dramatically lower in chickens and moderately lower in mosquitoes, indicating that RNA helicase is a major fitness determinant of WNV and that the effect on fitness is host specific. Overall, this work highlights the complex relationships that exist between individual and group phenotypes in RNA viruses and identifies RNA helicase as an attenuation and fitness determinant in WNV. 相似文献
339.
Dahn JR Fitzpatrick SL Llabre MM Apterbach GS Helms RL Cugnetto ML Klaus J Florez H Lawler T 《Obesity (Silver Spring, Md.)》2011,19(5):977-981
In the year 2000, 31% of women and 40% of men receiving outpatient care at Veteran Affairs (VA) medical facilities were overweight (BMI ≥25 and <30 kg/m(2)); 37.4% of women and 32.9% of men were obese (BMI ≥30 kg/m(2)). The purpose of the present study was to assess treatment effects of MOVE! Weight Management Program for Veterans by comparing the trajectory of change in weight postintervention (3, 6, and 12 months postenrollment) to a preintervention period (1, 3, and 5 years before enrollment). The sample consisted of 862 veterans participating in MOVE! at the Miami VA. All veterans participated in a 2-h Self-Management Support (SMS) session, which involved completion of a self-assessment questionnaire and a nutrition education group session. After completing SMS, veterans had the option of continuing with Supportive Group Sessions (SGS), which included 10-weekly group sessions led by a multidisciplinary team. Veterans served as their own controls in the analyses. Veterans gained 2 kg/year before enrolling in MOVE!. There were similar increases in weight across sex, racial/ethnic groups, and treatment condition. Weight for participants in SMS stabilized after enrollment whereas participants in SGS had an average weight loss of 1.6 kg/year. The preintervention slope for weight was significantly different from the postintervention slope, suggesting treatment effect. Findings from this study support the need for a lifestyle modification program such as MOVE! in primary care settings to assist overweight and obese patients in managing their weight. 相似文献
340.
Yi-Wei Lee Ching-Ching Yang Greta S. P. Mok Wei-Yip Law Cheng-Tau Su Tung-Hsin Wu 《PloS one》2012,7(11)