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Hosoya T  Araya K 《Zoological science》2005,22(12):1305-1318
As a first step in reconstructing the phylogeny of world stag beetles (Coleoptera: Lucanidae), phylogenetic relationships among the major members of Japanese stag beetles were explored by analyzing a sequence of 1030 nucleotides from the mitochondrial 16S ribosomal RNA (16S rRNA) gene. A total of 20 species and three additional subspecies representing 13 genera were examined to provide basic information on the phylogeny of world Lucanidae. The resultant phylogenetic tree indicates that the family Lucanidae is monophyletic, and contains two major lineages: one consists of the genera Platycerus, Aesalus, Ceruchus, and Nicagus, and the other includes Dorcus, Rhaetulus, Prosopocoilus, Aegus, Neolucanus, Prismognathus, Lucanus, Figulus, and Nigidius. Generic members of the latter lineage are further divided into the following four sublineages: i) Figulus and Nigidius; ii) Prismognathus and Lucanus; iii) Aegus and Neolucanus; and iv) Dorcus, Rhaetulus, and Prosopocoilus. These molecular phylogenetic relationships are used as a basis for a preliminary exploration of the evolution of sexual dimorphism in the shape of the mandible. The results of this investigation suggest that strong sexual dimorphism with well-developed mandibles in males evolved independently at least twice, once in the genus Aegus and once in the ancestor of the Lucanus-Prismognathus and Dorcus-Rhaetulus-Prosopocoilus clades. Alternatively, it is possible that sexual dimorphism of mandibles has undergone secondary loss in the genera Figulus and Nigidius.  相似文献   
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Two bis-tetrahydrofuran acetogenins, squamocin-O(1) (1) and squamocin-O(2) (2), were isolated from a MeOH extract of seeds of Annona squamosa L. Their structures were determined by spectral means including precursor-ion scanning mass spectral analysis for their aminal derivatives. The configurations at the oxymethine chiral centers were assigned as 12R,15R,16R,19R,20R,23R,24S,28S,36S for 1 and 12S,15R,16R,19R,20R,23R,24S, 28S,36S for 2, based on 1H NMR analysis of their Mosher's ester derivatives and CD data.  相似文献   
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Several studies have demonstrated that diabetes is a risk factor for developing periodontal disease, increasing its prevalence and severity. Furthermore, periodontitis may impair the metabolic control and adequate treatment of diabetic patients. LPS from Gram-negative bacteria penetrates the periodontal tissues and subsequently recruits and activates immune cells. Progression to severe periodontitis with loss of supporting structures is mediated by several factors, including secretion of a broad spectrum of inflammatory and destructive (PGE2). mediators such as cytokines (TNF-alpha, IL-1b and IL-6), chemokines (IL-8) and prostaglandin E2. The aim of this work is to investigate differences in the TNF-a, IL-1b and IL-6 expression and prostaglandin E2 (PGE2) release in blood from diabetic patients with and without aggressive periodontitis (AP) stimulated with lipopolysaccharide (LPS). For this purpose we recruited 29 Type 1 diabetes mellitus (DM) patients, 14 with AP and 15 without AP. Fourteen healthy individuals formed the control group. For cytokine expression and PGE2 secretion, an ex vivo whole blood culture system was used. Cytokines and PGE2 were detected by commercial immunometric assays. A wide range of inter-individual variability in spontaneous and LPS-induced TNF-alpha, IL-1b and IL-6 levels in patient groups and controls was found. The mean of spontaneous and LPS-induced TNF-alpha and IL-1b levels did not differ significantly (p > 0.5) when patients were compared to control individuals. Although not significant, the spontaneous TNF-alpha, IL-1b and IL-6 levels in the group of Type 1 DM with AP were higher than in controls, while in diabetic patients without AP, these values were depressed in comparison with controls. In both groups of patients, the means of LPS-induced IL-6 levels were higher than the controls but the differences observed were not significant (p = 0.07). However, the LPS-induced PGE2 levels varied significantly when all groups were compared (p = 0.007). The means of LPS-induced PGE2 levels for Type 1 diabetic patients with AP (p = 0.0009) and without AP (p = 0.024) were significantly higher than the levels observed for healthy controls. Finally, we conclude that Type 1 diabetic patients with or without AP did not express higher LPS-induced TNF-a, IL-1b and IL-6 levels than controls. However, the PGE2 levels released were significantly higher than those detected in controls.  相似文献   
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In a field collection performed at Pan de Azúcar Island in Northern Chile, 95 specimens representing all instars of Mepraia spinolai were collected. The intestinal contents of 55 specimens were examined for Trypanosoma cruzi infection and were found to be negative. This is the first record of an insular habitat for M. spinolai, where the insects had fed mainly on seabirds (78%), some on marine mammals (5%), and some on reptiles (7%).  相似文献   
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Background

There is a recognized gap in the evidence base relating to the nature and components of interventions to address the psycho-social needs of HIV positive young people. We used mixed methods research to strengthen a community support group intervention for HIV positive young people based in Harare, Zimbabwe.

Methods

A quantitative questionnaire was administered to HIV positive Africaid support group attendees. Afterwards, qualitative data were collected from young people aged 15–18 through tape-recorded in-depth interviews (n = 10), 3 focus group discussions (FGDs) and 16 life history narratives. Data were also collected from caregivers, health care workers, and community members through FGDs (n = 6 groups) and in-depth interviews (n = 12). Quantitative data were processed and analysed using STATA 10. Qualitative data were analysed using thematic analysis.

Results

229/310 young people completed the quantitative questionnaire (74% participation). Median age was 14 (range 6–18 years); 59% were female. Self-reported adherence to antiretrovirals was sub-optimal. Psychological well being was poor (median score on Shona Symptom Questionnaire 9/14); 63% were at risk of depression. Qualitative findings suggested that challenges faced by positive children include verbal abuse, stigma, and discrimination. While data showed that support group attendance is helpful, young people stressed that life outside the confines of the group was more challenging. Caregivers felt ill-equipped to support the children in their care. These data, combined with a previously validated conceptual framework for family-centred interventions, were used to guide the development of the existing programme of adolescent support groups into a more comprehensive evidence-based psychosocial support programme encompassing caregiver and household members.

Conclusions

This study allowed us to describe the lived experiences of HIV positive young people and their caregivers in Zimbabwe. The findings contributed to the enhancement of Africaid’s existing programme of support to better promote psychological well being and ART adherence.  相似文献   
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