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51.
Guillermo López Marcos López-Parra Germán Garrote Leonardo Fernández Teresa del Rey-Wamba Rafael Arenas-Rojas Maribel García-Tardío Gema Ruiz Irene Zorrilla Manuel Moral Miguel A. Simón 《European Journal of Wildlife Research》2014,60(2):359-366
The conservation of endangered species requires accurate data, and knowledge of cause-specific mortality rates is one of the most important issues. In recent years, conservation programs for the critically endangered Iberian lynx Lynx pardinus have been developed on the basis of mortality data derived 30 years ago from the small Doñana population. Thus, there is an urgent need for an update of mortality rates and causes in both populations (Sierra Morena and Doñana). Here we use radio-tracking information from the whole range of the Iberian lynx to quantify mortality rates and identify their causes. Between 2006 and 2011, we radio-tagged 78 Iberian lynxes from its two remaining populations (39 from Sierra Morena and 39 from Doñana). Mortality events were evaluated to identify causes, and cause-specific annual mortality rates (AMR) were obtained using the nonparametric cumulative incidence function estimator. Overall, AMR was estimated at 0.16?±?0.05 (0.19?±?0.09 in Sierra Morena and 0.12?±?0.07 in Doñana). Disease was the main cause of mortality both for the whole population and the Doñana population. Poaching was the main cause of mortality in Sierra Morena. Our results suggest that the best strategy for conserving this species is to focus action on decreasing the fatal effect of disease and poaching. Given the possible existence of an underlying inbreeding-mediated immunosuppression, genetic management aimed at increasing the genetic diversity of this population is also recommended. 相似文献
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Vogt S Portig I Irqsusi M Ruppert V Weber P Ramzan R 《Journal of bioenergetics and biomembranes》2011,43(4):425-435
Induction of heat shock proteins (hsp) has been shown to protect cells from ischemia by providing transient tolerance against
myocardial injury and improving postischemic functional recovery. Attenuation of ATP depletion and earlier restoration of
ATP content on reperfusion are thought to play a role in this scenario. Hsp induction is accompanied by altered enzyme activity
of the respiratory chain, the major generator of ATP under physiological conditions. This report addresses the question whether
processing and final assembly of the active holoenzyme cytochrome c oxidase (CcO, complex IV), member of the respiratory chain,
is compromised under hypoxic conditions unless protected by stress proteins. Special focus is laid on function of the enzyme’s
subunits and importance of cellular energy availability and maintenance. 相似文献
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Implementing a recall paradigm without hypnosis, we use functional MRI (fMRI) to explore and compare nociceptive and centrally-driven pain experiences. We posit that a trace of a recent nociceptive event can be used to create sensory-re-experiencing of pain that can be qualified in terms of intensity and vividness. Fifteen healthy volunteers received three levels of thermal stimuli (warm, low pain and high pain) and subsequently were asked to recall and then rate this experience. Neuroimaging results reveal that recalling a previous sensory experience activates an extensive network of classical pain processing structures except the contralateral posterior insular cortex. Nociceptive-specific activation of this structure and the rated intensity difference between physical and recalled pain events allow us to investigate the link between the quality of the original nociceptive stimulus and the mental trace, as well as the differences between the accompanying neural responses. Additionally, by incorporating the behavioural ratings, we explored which brain regions were separately responsible for generating either an accurate or vivid recall of the physical experience. Together, these observations further our understanding of centrally-mediated pain experiences and pain memory as well as the potential relevance of these factors in the maintenance of chronic pain. 相似文献
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Shanil Ebrahim Luis Montoya Wanda Truong Sandy Hsu Mostafa Kamal el Din Alonso Carrasco-Labra Jason W. Busse Stephen D. Walter Diane Heels-Ansdell Rachel Couban Irene Patelis-Siotis Marg Bellman L. Esther de Graaf David J. A. Dozois Peter J. Bieling Gordon H. Guyatt 《PloS one》2012,7(11)
Objectives
To systematically summarize the randomized trial evidence regarding the relative effectiveness of cognitive behavioural therapy (CBT) in patients with depression in receipt of disability benefits in comparison to those not receiving disability benefits.Data Sources
All relevant RCTs from a database of randomized controlled and comparative studies examining the effects of psychotherapy for adult depression (http://www.evidencebasedpsychotherapies.org), electronic databases (MEDLINE, EMBASE, PSYCINFO, AMED, CINAHL and CENTRAL) to June 2011, and bibliographies of all relevant articles.Study Eligibility Criteria, Participants and Intervention
Adult patients with major depression, randomly assigned to CBT versus minimal/no treatment or care-as-usual.Study Appraisal and Synthesis Methods
Three teams of reviewers, independently and in duplicate, completed title and abstract screening, full text review and data extraction. We performed an individual patient data meta-analysis to summarize data.Results
Of 92 eligible trials, 70 provided author contact information; of these 56 (80%) were successfully contacted to establish if they captured receipt of benefits as a baseline characteristic; 8 recorded benefit status, and 3 enrolled some patients in receipt of benefits, of which 2 provided individual patient data. Including both patients receiving and not receiving disability benefits, 2 trials (227 patients) suggested a possible reduction in depression with CBT, as measured by the Beck Depression Inventory, mean difference [MD] (95% confidence interval [CI]) = −2.61 (−5.28, 0.07), p = 0.06; minimally important difference of 5. The effect appeared larger, though not significantly, in those in receipt of benefits (34 patients) versus not receiving benefits (193 patients); MD (95% CI) = −4.46 (−12.21, 3.30), p = 0.26.Conclusions
Our data does not support the hypothesis that CBT has smaller effects in depressed patients receiving disability benefits versus other patients. Given that the confidence interval is wide, a decreased effect is still possible, though if the difference exists, it is likely to be small. 相似文献57.
William Coley Rachel Van Duyne Lawrence Carpio Irene Guendel Kylene Kehn-Hall Sebastien Chevalier Aarthi Narayanan Truong Luu Norman Lee Zachary Klase Fatah Kashanchi 《The Journal of biological chemistry》2010,285(42):31930-31943
MicroRNAs (miRNAs) are a class of small RNA molecules that function to control gene expression and restrict viral replication in host cells. The production of miRNAs is believed to be dependent upon the DICER enzyme. Available evidence suggests that in T lymphocytes, HIV-1 can both suppress and co-opt the host''s miRNA pathway for its own benefit. In this study, we examined the state of miRNA production in monocytes and macrophages as well as the consequences of viral infection upon the production of miRNA. Monocytes in general express low amounts of miRNA-related proteins, and DICER in particular could not be detected until after monocytes were differentiated into macrophages. In the case where HIV-1 was present prior to differentiation, the expression of DICER was suppressed. MicroRNA chip results for RNA isolated from transfected and treated cells indicated that a drop in miRNA production coincided with DICER protein suppression in macrophages. We found that the expression of DICER in monocytes is restricted by miR-106a, but HIV-1 suppressed DICER expression via the viral gene Vpr. Additionally, analysis of miRNA expression in monocytes and macrophages revealed evidence that some miRNAs can be processed by both DICER and PIWIL4. Results presented here have implications for both the pathology of viral infections in macrophages and the biogenesis of miRNAs. First, HIV-1 suppresses the expression and function of DICER in macrophages via a previously unknown mechanism. Second, the presence of miRNAs in monocytes lacking DICER indicates that some miRNAs can be generated by proteins other than DICER. 相似文献
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