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排序方式: 共有1018条查询结果,搜索用时 228 毫秒
61.
Rick A. Brenneman Adam T. McLain Justin M. Taylor John R. Zaonarivelo Runhua Lei Susie M. McGuire Rambinintsoa Andriantompohavana Anthony B. Rylands Edward E. LouisJr. 《International journal of primatology》2016,37(3):460-477
Subspecies were traditionally defined by identifying gaps between phenotypes across the geographic range of a species, and may represent important units in the development of conservation strategies focused on preserving genetic diversity. Previous taxonomic research proposed that phenotypic variation between scattered Indri indri populations warranted the naming of two distinct subspecies, I. i. indri and I. i. variegatus. We tested these subspecific designations using mitochondrial sequence data generated from the control region or D-loop (569 bp) and a large section (2362 bp) of multiple genes and tRNAs known as Pastorini’s fragment and nuclear microsatellite markers. This study used 114 samples of I. indri from 12 rainforest sites in eastern Madagascar, encompassing the entire range of the species. These genetic samples represent multiple populations from low- and high-elevation forests from both putative subspecies. Molecular analyses of the mitochondrial sequence data did not support the two proposed subspecies. Furthermore, the microsatellite analyses showed no significant differences across the range beyond population level differentiation. This study demonstrates the utility of incorporating multiple lines of evidence in addition to phenotypic traits to define species or subspecies. 相似文献
62.
Clinical,socio‐demographic and psychological characteristics in individuals with persistent psychotic experiences with and without a “need for care”
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Emmanuelle Peters Thomas Ward Mike Jackson Craig Morgan Monica Charalambides Philip McGuire Peter Woodruff Pamela Jacobsen Paul Chadwick Philippa A. Garety 《World psychiatry》2016,15(1):41-52
Individuals reporting persistent psychotic experiences (PEs) in the general population, but without a “need for care”, are a unique group of particular importance in identifying risk and protective factors for psychosis. We compared people with persistent PEs and no “need for care” (non‐clinical, N=92) with patients diagnosed with a psychotic disorder (clinical, N=84) and controls without PEs (N=83), in terms of their phenomenological, socio‐demographic and psychological features. The 259 participants were recruited from one urban and one rural area in the UK, as part of the UNIQUE (Unusual Experiences Enquiry) study. Results showed that the non‐clinical group experienced hallucinations in all modalities as well as first‐rank symptoms, with an earlier age of onset than in the clinical group. Somatic/tactile hallucinations were more frequent than in the clinical group, while commenting and conversing voices were rare. Participants in the non‐clinical group were differentiated from their clinical counterparts by being less paranoid and deluded, apart from ideas of reference, and having fewer cognitive difficulties and negative symptoms. Unlike the clinical group, they were characterized neither by low psychosocial functioning nor by social adversity. However, childhood trauma featured in both groups. They were similar to the controls in psychological characteristics: they did not report current emotional problems, had intact self‐esteem, displayed healthy schemas about the self and others, showed high life satisfaction and well‐being, and high mindfulness. These findings support biopsychosocial models postulating that environmental and psychological factors interact with biological processes in the aetiology of psychosis. While some PEs may be more malign than others, lower levels of social and environmental adversity, combined with protective factors such as intact IQ, spirituality, and psychological and emotional well‐being, may reduce the likelihood of persistent PEs leading to pathological outcomes. Future research should focus on protective factors and determinants of well‐being in the context of PEs, rather than exclusively on risk factors and biomarkers of disease states. 相似文献
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Mary S. Pampusch Hadia M. Abdelaal Emily K. Cartwright Jhomary S. Molden Brianna C. Davey Jordan D. Sauve Emily N. Sevcik Aaron K. Rendahl Eva G. Rakasz Elizabeth Connick Edward A. Berger Pamela J. Skinner 《PLoS pathogens》2022,18(2)
During chronic human immunodeficiency virus (HIV) or simian immunodeficiency virus (SIV) infection prior to AIDS progression, the vast majority of viral replication is concentrated within B cell follicles of secondary lymphoid tissues. We investigated whether infusion of T cells expressing an SIV-specific chimeric antigen receptor (CAR) and the follicular homing receptor, CXCR5, could successfully kill viral-RNA+ cells in targeted lymphoid follicles in SIV-infected rhesus macaques. In this study, CD4 and CD8 T cells from rhesus macaques were genetically modified to express antiviral CAR and CXCR5 moieties (generating CAR/CXCR5-T cells) and autologously infused into a chronically infected animal. At 2 days post-treatment, the CAR/CXCR5-T cells were located primarily in spleen and lymph nodes both inside and outside of lymphoid follicles. Few CAR/CXCR5-T cells were detected in the ileum, rectum, and lung, and no cells were detected in the bone marrow, liver, or brain. Within follicles, CAR/CXCR5-T cells were found in direct contact with SIV-viral RNA+ cells. We next infused CAR/CXCR5-T cells into ART-suppressed SIV-infected rhesus macaques, in which the animals were released from ART at the time of infusion. These CAR/CXCR5-T cells replicated in vivo within both the extrafollicular and follicular regions of lymph nodes and accumulated within lymphoid follicles. CAR/CXR5-T cell concentrations in follicles peaked during the first week post-infusion but declined to undetectable levels after 2 to 4 weeks. Overall, CAR/CXCR5-T cell-treated animals maintained lower viral loads and follicular viral RNA levels than untreated control animals, and no outstanding adverse reactions were noted. These findings indicate that CAR/CXCR5-T cell treatment is safe and holds promise as a future treatment for the durable remission of HIV. 相似文献
65.
Formulation of entomopathogenic nematode-infected cadavers 总被引:1,自引:0,他引:1
Entomopathogenic nematodes are commercially applied in aqueous suspension. These biocontrol agents may also be applied in nematode-infected insect cadavers, but this approach may entail problems in storage and ease of handling. We determined the feasibility of formulating nematode-infected insect cadavers to overcome these hindrances. All experiments were conducted with Heterorhabditis bacteriophora Poinar and Galleria mellonella (L.). Nonformulated cadavers were used as controls. Of 19 formulations tested (including combinations of starches, flours, clays, etc.) 1 (starch-clay combination) was found to adhere to the cadaver and to have no significant deleterious effects on nematode reproduction and infectivity; other formulations exhibited poor adhesion or reduced nematode reproduction. Two formulations enabled cadavers to be partially desiccated without affecting reproduction; other formulations and nonformulated cadavers exhibited reduced reproduction upon desiccation. Four-day-old cadavers were more amenable to desiccation than 8-day-old cadavers. Formulated cadavers were more resistant to rupturing and sticking together during agitation than nonformulated cadavers. 相似文献
66.
McGuire AM McAllister M Wills RA Tranas JD 《International journal for parasitology》1999,29(10):1525-1529
Dogs are a definitive host of Neospora caninum and cattle are intermediate hosts. Alternative life-cycles have not been investigated. Foxes are frequently seropositive, but may not commonly prey upon cattle; therefore, other intermediate hosts may exist that are frequent prey of foxes. Three domestic pigeons (Columbia livia) and three zebra finches (Poephila guttata) were inoculated with N. caninum tachyzoites, to determine if they could serve as intermediate hosts. Tissue culture, PCR, serology, and histology were all positive for one or more pigeons. All finches resisted infection. Further testing of columbiform birds as intermediate hosts of N. caninum is warranted. 相似文献
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68.
D.?Park J.?M.?McGuire A.?L.?Majchrzak J.?M.?Ziobro H.?L.?EisthenEmail author 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2004,190(5):415-427
Chemosensory cues play an important role in the daily lives of salamanders, mediating foraging, conspecific recognition, and territorial advertising. We investigated the behavioral effects of conspecific whole-body odorants in axolotls, Ambystoma mexicanum, a salamander species that is fully aquatic. We found that males increased general activity when exposed to female odorants, but that activity levels in females were not affected by conspecific odorants. Although males showed no difference in courtship displays across testing conditions, females performed courtship displays only in response to male odorants. We also found that electro-olfactogram responses from the olfactory and vomeronasal epithelia were larger in response to whole-body odorants from the opposite sex than from the same sex. In males, odorants from gravid and recently spawned females evoked different electro-olfactogram responses at some locations in the olfactory and vomeronasal epithelia; in general, however, few consistent differences between the olfactory and vomeronasal epithelia were observed. Finally, post hoc analyses indicate that experience with opposite-sex conspecifics affects some behavioral and electrophysiological responses. Overall, our data indicate that chemical cues from conspecifics affect general activity and courtship behavior in axolotls, and that both the olfactory and vomeronasal systems may be involved in discriminating the sex and reproductive condition of conspecifics.Abbreviations EOG electro-olfactogram - VNO vomeronasal organ 相似文献
69.
Haack SK Fogarty LR West TG Alm EW McGuire JT Long DT Hyndman DW Forney LJ 《Environmental microbiology》2004,6(5):438-448
In a contaminated water-table aquifer, we related microbial community structure on aquifer sediments to gradients in 24 geochemical and contaminant variables at five depths, under three recharge conditions. Community amplified ribsosomal DNA restriction analysis (ARDRA) using universal 16S rDNA primers and denaturing gradient gel electrophoresis (DGGE) using bacterial 16S rDNA primers indicated: (i). communities in the anoxic, contaminated central zone were similar regardless of recharge; (ii). after recharge, communities at greatest depth were similar to those in uncontaminated zones; and (iii). after extended lack of recharge, communities at upper and lower aquifer margins differed from communities at the same depths on other dates. General aquifer geochemistry was as important as contaminant or terminal electron accepting process (TEAP) chemistry in discriminant analysis of community groups. The Shannon index of diversity (H) and the evenness index (E), based on DGGE operational taxonomic units (OTUs), were statistically different across community groups and aquifer depths. Archaea or sulphate-reducing bacteria 16S rRNA abundance was not clearly correlated with TEAP chemistry indicative of methanogenesis or sulphate reduction. Eukarya rRNA abundance varied by depth and date from 0 to 13% of the microbial community. This contaminated aquifer is a dynamic ecosystem, with complex interactions between physical, chemical and biotic components, which should be considered in the interpretation of aquifer geochemistry and in the development of conceptual or predictive models for natural attenuation or remediation. 相似文献
70.
The small-subunit (SSU) processome is a large ribonucleoprotein required for the biogenesis of the 18S rRNA and likely corresponds to the terminal knobs visualized by electron microscopy on the 5' end of nascent rRNAs. The original purification of the SSU processome of Saccharomyces cerevisiae resulted in the identification of 28 proteins. Here, we characterize 12 additional protein components, including five small-ribosomal-subunit proteins (Rps4, Rps6, Rps7, Rps9, and Rps14) that had previously been copurified. Our multiple criteria for including a component as a bona fide SSU processome component included coimmunoprecipitation with Mpp10 (an SSU processome component), the U3 snoRNA, and the anticipated pre-rRNAs. Importantly, the association of specific ribosomal proteins with the SSU processome suggests that the SSU processome has roles in both pre-rRNA processing and ribosome assembly. These ribosomal proteins may be analogous to the primary or secondary RNA binding proteins first described in bacterial in vitro ribosome assembly maps. In addition to the ribosomal proteins and based on the same experimental approach, we found seven other proteins (Utp18, Noc4, Utp20, Utp21, Utp22, Emg1, and Krr1) to be bona fide SSU processome proteins. 相似文献