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641.
Megan S. Dunbar Mi-Suk Kang Dufour Barrot Lambdin Imelda Mudekunye-Mahaka Definate Nhamo Nancy S. Padian 《PloS one》2014,9(11)
Adolescent females in Zimbabwe are at high risk for HIV acquisition. Shaping the Health of Adolescents in Zimbabwe (SHAZ!) was a randomized controlled trial of a combined intervention package including life-skills and health education, vocational training, micro-grants and social supports compared to life-skills and health education alone. SHAZ! was originally envisioned as a larger effectiveness trial, however, the intervention was scaled back due to contextual and economic conditions in the country at the time. SHAZ! enrolled 315 participants randomly assigned to study arm within blocks of 50 participants (158 intervention and 157 control). The intervention arm participants showed statistically significant differences from the control arm participants for several outcomes during the two years of follow up including; reduced food insecurity [IOR = 0.83 vs. COR = 0.68, p-0.02], and having their own income [IOR = 2.05 vs. COR = 1.67, p = 0.02]. Additionally, within the Intervention arm there was a lower risk of transactional sex [IOR = 0.64, 95% CI (0.50, 0.83)], and a higher likelihood of using a condom with their current partner [IOR = 1.79, 95% CI (1.23, 2.62)] over time compared to baseline. There was also evidence of fewer unintended pregnancies among intervention participants [HR = 0.61, 95% CI (0.37, 1.01)], although this relationship achieved only marginal statistical significance. Several important challenges in this study included the coordination with vocational training programs, the political and economic instability of the area at the time of the study, and the difficulty in creating a true standard of care control arm. Overall the results of the SHAZ! study suggest important potential for HIV prevention intervention packages that include vocational training and micro-grants, and lessons for further economic livelihoods interventions with adolescent females. Further work is needed to refine the intervention model, and test the impact of the intervention at scale on biological outcomes.
Trial Registration
ClinicalTrials.gov NCT02034214相似文献642.
Benjamin C. Trumble Steven J. C. Gaulin Matt D. Dunbar Hillard Kaplan Michael Gurven 《Human nature (Hawthorne, N.Y.)》2016,27(1):51-67
Sex differences in reproductive strategy and the sexual division of labor resulted in selection for and maintenance of sexual dimorphism across a wide range of characteristics, including body size, hormonal physiology, behavior, and perhaps spatial abilities. In laboratory tasks among undergraduates there is a general male advantage for navigational and mental-rotation tasks, whereas studies find female advantage for remembering item locations in complex arrays and the locations of plant foods. Adaptive explanations of sex differences in these spatial abilities have focused on patterns of differential mate search and routine participation in distinct subsistence behaviors. The few studies to date of spatial ability in nonindustrial populations practicing subsistence lifestyles, or across a wider age range, find inconsistent results. Here we examine sex- and age-based variation in one kind of spatial ability related to navigation, dead-reckoning, among Tsimane forager horticulturalists living in lowland Bolivia. Seventy-three participants (38 male) aged 6–82 years pointed a handheld global positioning system (GPS) unit toward the two nearest communities and the more distant market town. We find no evidence of sex differences in dead reckoning (p?=?0.47), nor do we find any evidence of age-related decline in dead-reckoning accuracy (p?=?0.28). Participants were significantly more accurate at pointing toward the market town than toward the two nearest villages despite its being significantly farther away than the two nearest communities. Although Tsimane do show sexual dimorphism in foraging tasks, Tsimane women have extensive daily and lifetime travel, and the local environment lacks directional cues that typically enhance male navigation. This study raises the possibility that greater similarity in mobility patterns because of overlapping subsistence strategies and activities may result in convergence of some male and female navigation abilities. 相似文献
643.
The challenge for those responsible for funding, brokering and assessing the merit of proposed Indigenous research is to identify and then work co-operatively with appropriate representatives of Indigenous interests in order to increase the flow of benefits from research to Indigenous peoples. Experience in Australia has shown that this is not a straightforward process. In this paper we indicate some reasons why it is important for the research community to broker research with representative Indigenous organisations and to involve Indigenous peoples in the ethical assessment and conduct of research. We then identify some barriers to the achievement of these objectives and outline recently developed interventions from the field of health research that aim to promote a more effective working relationship between Indigenous peoples and members of the research community.
相似文献
Terry DunbarEmail: |
644.
Correction of X-linked chronic granulomatous disease by gene therapy, augmented by insertional activation of MDS1-EVI1, PRDM16 or SETBP1 总被引:18,自引:0,他引:18
Ott MG Schmidt M Schwarzwaelder K Stein S Siler U Koehl U Glimm H Kühlcke K Schilz A Kunkel H Naundorf S Brinkmann A Deichmann A Fischer M Ball C Pilz I Dunbar C Du Y Jenkins NA Copeland NG Lüthi U Hassan M Thrasher AJ Hoelzer D von Kalle C Seger R Grez M 《Nature medicine》2006,12(4):401-409
Gene transfer into hematopoietic stem cells has been used successfully for correcting lymphoid but not myeloid immunodeficiencies. Here we report on two adults who received gene therapy after nonmyeloablative bone marrow conditioning for the treatment of X-linked chronic granulomatous disease (X-CGD), a primary immunodeficiency caused by a defect in the oxidative antimicrobial activity of phagocytes resulting from mutations in gp91(phox). We detected substantial gene transfer in both individuals' neutrophils that lead to a large number of functionally corrected phagocytes and notable clinical improvement. Large-scale retroviral integration site-distribution analysis showed activating insertions in MDS1-EVI1, PRDM16 or SETBP1 that had influenced regulation of long-term hematopoiesis by expanding gene-corrected myelopoiesis three- to four-fold in both individuals. Although insertional influences have probably reinforced the therapeutic efficacy in this trial, our results suggest that gene therapy in combination with bone marrow conditioning can be successfully used to treat inherited diseases affecting the myeloid compartment such as CGD. 相似文献
645.
Metabolic complementarity and genomics of the dual bacterial symbiosis of sharpshooters 总被引:10,自引:3,他引:7 下载免费PDF全文
Wu D Daugherty SC Van Aken SE Pai GH Watkins KL Khouri H Tallon LJ Zaborsky JM Dunbar HE Tran PL Moran NA Eisen JA 《PLoS biology》2006,4(6):e188
Mutualistic intracellular symbiosis between bacteria and insects is a widespread phenomenon that has contributed to the global success of insects. The symbionts, by provisioning nutrients lacking from diets, allow various insects to occupy or dominate ecological niches that might otherwise be unavailable. One such insect is the glassy-winged sharpshooter (Homalodisca coagulata), which feeds on xylem fluid, a diet exceptionally poor in organic nutrients. Phylogenetic studies based on rRNA have shown two types of bacterial symbionts to be coevolving with sharpshooters: the gamma-proteobacterium Baumannia cicadellinicola and the Bacteroidetes species Sulcia muelleri . We report here the sequencing and analysis of the 686,192–base pair genome of B. cicadellinicola and approximately 150 kilobase pairs of the small genome of S. muelleri, both isolated from H. coagulata. Our study, which to our knowledge is the first genomic analysis of an obligate symbiosis involving multiple partners, suggests striking complementarity in the biosynthetic capabilities of the two symbionts: B. cicadellinicola devotes a substantial portion of its genome to the biosynthesis of vitamins and cofactors required by animals and lacks most amino acid biosynthetic pathways, whereas S. muelleri apparently produces most or all of the essential amino acids needed by its host. This finding, along with other results of our genome analysis, suggests the existence of metabolic codependency among the two unrelated endosymbionts and their insect host. This dual symbiosis provides a model case for studying correlated genome evolution and genome reduction involving multiple organisms in an intimate, obligate mutualistic relationship. In addition, our analysis provides insight for the first time into the differences in symbionts between insects (e.g., aphids) that feed on phloem versus those like H. coagulata that feed on xylem. Finally, the genomes of these two symbionts provide potential targets for controlling plant pathogens such as Xylella fastidiosa, a major agroeconomic problem, for which H. coagulata and other sharpshooters serve as vectors of transmission. 相似文献
646.
647.
Donald SA McLeod 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2010,31(1):9-19
This paper provides an overview on the biology, monitoring and management of differentiated thyroid cancer (DTC), with particular attention to issues of relevance to clinical chemistry. The incidence of DTC appears to be increasing and management strategies are evolving as we learn more about its natural history and response to therapy. Clinical chemistry techniques play a central role in these protocols. Technical limitations inherent in current monitoring tools can hamper follow-up, although progress is being made. The molecular basis of DTC is being delineated with the potential to develop new strategies for diagnosis, monitoring and management of this condition. 相似文献
648.
649.
Retrovirus-mediated transfer and expression of the interleukin-3 gene in mouse hematopoietic cells result in a myeloproliferative disorder. 总被引:18,自引:1,他引:18 下载免费PDF全文
P M Wong S W Chung C E Dunbar D M Bodine S Ruscetti A W Nienhuis 《Molecular and cellular biology》1989,9(2):798-808
A high-titer, recombinant retroviral vector produced in psi 2 packaging cells has been used to introduce the murine interleukin-3 (IL-3) gene into mouse hematopoietic cells. Integration and expression of the IL-3 gene was observed in spleen foci from which could be derived factor-independent, continuously proliferating cell lines. Irradiated or genetically anemic W/Wv recipients of infected hematopoietic cells developed a myeloproliferative syndrome characterized by a marked elevation in leukocyte count, bone marrow hyperplasia, and enlargement of the liver and spleen. The syndrome reflected proliferation of one or more stem cell clones, the progeny of which were capable of repopulating secondary recipients. One animal developed the syndrome primarily by a paracrine mechanism. Endogenous IL-3 production caused amplification of hematopoietic cells but did not appear to alter the maturational or self-renewal potential of these cells. 相似文献
650.
Robin I. M. Dunbar Susanne Shultz 《Biological reviews of the Cambridge Philosophical Society》2021,96(5):1889-1906
Compared to most other mammals and birds, anthropoid primates have unusually complex societies characterised by bonded social groups. Among primates, this effect is encapsulated in the social brain hypothesis: the robust correlation between various indices of social complexity (social group size, grooming clique size, tactical behaviour, coalition formation) and brain size. Hitherto, this has always been interpreted as a simple, unitary relationship. Using data for five different indices of brain volume from four independent brain databases, we show that the distribution of group size plotted against brain size is best described as a set of four distinct, very narrowly defined grades which are unrelated to phylogeny. The allocation of genera to these grades is highly consistent across the different data sets and brain indices. We show that these grades correspond to the progressive evolution of bonded social groups. In addition, we show, for those species that live in multilevel social systems, that the typical sizes of the different grouping levels in each case coincide with different grades. This suggests that the grades correspond to demographic attractors that are especially stable. Using five different cognitive indices, we show that the grades correlate with increasing social cognitive skills, suggesting that the cognitive demands of managing group cohesion increase progressively across grades. We argue that the grades themselves represent glass ceilings on animals' capacity to maintain social and spatial coherence during foraging and that, in order to evolve more highly bonded groups, species have to be able to invest in costly forms of cognition. 相似文献