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991.
The flow of mitochondria in chicken sciatic nerve 总被引:4,自引:0,他引:4
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Mark J. Statham Deborah A. Woollett Susan Fresquez Jerene Pfeiffer Jonathan Richmond Alice Whitelaw Ngaio L. Richards Michael F. Westphal Benjamin N. Sacks 《The Journal of wildlife management》2020,84(1):66-74
Noninvasive fecal sampling combined with genetic analysis is a technique allowing the study of elusive or otherwise difficult to monitor species without the need for direct contact. Although this method is widely used in birds and mammals, it has never been successfully applied on a large scale in reptiles. The blunt-nosed leopard lizard (Gambelia sila) is an endangered species endemic to the San Joaquin Desert, California, USA. Presently, acquiring data on the species for research and management involves more traditional methods such as live capture or visual surveys, the latter of which are required for regulatory monitoring in accordance with wildlife agency protocols. We used an approach for gathering additional information that combines conservation detection dogs trained to locate blunt-nosed leopard lizard scat samples with genetic analysis for identifying and distinguishing among sympatric lizard species. We developed 2 polymerase chain reaction assays that produce fluorescently labelled amplicons of species-specific fragment length for 6 lizard species in the study area. Using these assays, we genetically identified to species 78% (255 of 327) of samples collected by dog-handler teams across 4 years. The majority of the genetically identified samples (82.4%; 210 of 255) were confirmed as originating from blunt-nosed leopard lizards. Although an assessment of the viability of detection dogs in regulatory monitoring efforts is required, our ability to recover usable DNA and to differentiate among a diverse group of lizards highlights the broad potential of our methodology for noninvasive sampling in reptiles. © 2019 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. 相似文献
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Kallikreins, kinins and growth factor biosynthesis 总被引:5,自引:0,他引:5
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Erin K. Crane Suet-Yan Kwan Daisy I. Izaguirre Yvonne T. M. Tsang Lisa K. Mullany Zhifei Zu JoAnne S. Richards David M. Gershenson Kwong-Kwok Wong 《PloS one》2015,10(8)
Epithelial ovarian cancer is a diverse molecular and clinical disease, yet standard treatment is the same for all subtypes. TP53 mutations represent a node of divergence in epithelial ovarian cancer histologic subtypes and may represent a therapeutic opportunity in subtypes expressing wild type, including most low-grade ovarian serous carcinomas, ovarian clear cell carcinomas and ovarian endometrioid carcinomas, which represent approximately 25% of all epithelial ovarian cancer. We therefore sought to investigate Nutlin-3a—a therapeutic which inhibits MDM2, activates wild-type p53, and induces apoptosis—as a therapeutic compound for TP53 wild-type ovarian carcinomas. Fifteen epithelial ovarian cancer cell lines of varying histologic subtypes were treated with Nutlin-3a with determination of IC50 values. Western Blot (WB) and quantitative real-time polymerase chain reaction (qRT-PCR) analyses quantified MDM2, p53, and p21 expression after Nutlin-3a treatment. DNA from 15 cell lines was then sequenced for TP53 mutations in exons 2-11 including intron-exon boundaries. Responses to Nutlin-3a were dependent upon TP53 mutation status. By qRT-PCR and WB, levels of MDM2 and p21 were upregulated in wild-type TP53 sensitive cell lines, and p21 induction was reduced or absent in mutant cell lines. Annexin V assays demonstrated apoptosis in sensitive cell lines treated with Nutlin-3a. Thus, Nutlin-3a could be a potential therapeutic agent for ovarian carcinomas expressing wild-type TP53 and warrants further investigation. 相似文献
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Mai Stafford Catharine R. Gale Gita Mishra Marcus Richards Stephanie Black Diana L. Kuh 《PloS one》2015,10(6)
Background
Mental wellbeing, conceptualised as positive affect, life satisfaction and realisation of needs that contribute to psychological growth, captures more than the absence of mental ill health. Several nations now aim to monitor and improve mental wellbeing. Whilst many studies document associations between adverse childhood experiences and mental disorders in adulthood, possible links between childhood experiences and adult mental wellbeing have so far received less attention.Methods
Using data from 1976 men and women in the MRC National Survey for Health and Development, we investigated prospective associations between childhood socioeconomic and psychosocial environments and the Warwick Edinburgh Mental Wellbeing Scale, designed to capture both hedonic and eudaimonic facets of wellbeing, at age 60-64.Results
Whilst there was no evidence that childhood socioeconomic circumstances were related to later wellbeing independently of other childhood experiences, elements of childrearing and parenting, parental health and adjustment, and childhood illness were related. More advantaged socioeconomic position was associated with greater wellbeing but this did not explain the links between these childhood exposures and adult wellbeing, suggesting alternative explanatory pathways should be considered.Conclusions
Childhood illness and family psychosocial environment are associated with mental wellbeing in early older age, with effects sizes that are larger or comparable to socioeconomic circumstances in adulthood. Initiatives to improve the nation’s mental wellbeing that include programmes targeted to supporting families and children may additionally have benefits that continue into older age. 相似文献1000.
Verónica Fernandes Petr Triska Joana B. Pereira Farida Alshamali Teresa Rito Alison Machado Zuzana Fajko?ová Bruno Cavadas Viktor ?erny Pedro Soares Martin B. Richards Luísa Pereira 《PloS one》2015,10(3)
At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (∼8–37 generations for African input into Arabia, and 30–90 generations for “back-to-Africa” migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ∼2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ∼8 ka. The main “back-to-Africa” migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa. 相似文献