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51.
Placental oxidative stress is a feature of human labor. Heat shock proteins (HSPs) play a key role in cellular stress. We hypothesized that placental expression of the small HSP 27 would be altered during labor and expression would vary in different regions of the placenta. Six women in labor who delivered vaginally and 6 women not in labor, who were delivered by Cesarean section, were recruited. Four equally spaced pieces were sampled from the inner, middle and outer regions of each placenta (total 12 samples per placenta). HSP 27 expression was investigated by Western blot analysis and RT-PCR. For non-labor, there was less HSP 27 protein in the inner placenta region compared with both the middle region (p<0.05) and outer region (p<0.05). For labor, there was also less HSP 27 protein in the inner region compared with both the middle (p<0.02) and outer region (p<0.01). When the 3 regions of the placenta were compared for non-labor versus labor there was less HSP 27 in the labor group at both the inner (p<0.05) and middle regions (p<0.005) compared to non-labor. Similar to HSP 27 protein, there was less HSP 27 mRNA in the labor group in both the inner region (p<0.05) and middle region (p<0.02) compared to non-labor. This study suggests that placental HSP 27 may play a role in labor and is spatially controlled. The results have important implications for how data obtained from studies in the placenta can be influenced by sampling methods. 相似文献
52.
Amina Amadou Alban Fabre Gabriela Torres-Mejía Carolina Ortega-Olvera Angélica Angeles-Llerenas Fiona McKenzie Carine Biessy Pierre Hainaut Isabelle Romieu 《PloS one》2013,8(11)
The use of hormonal therapies, including hormonal contraceptives (HC) and postmenopausal hormone replacement therapy (HRT) have been shown to influence breast cancer (BC) risk. However, the variations of these effects among populations and ethnic groups are not completely documented, especially among Hispanic women. We evaluated the association between HC and premenopausal BC risk, and between HRT and postmenopausal BC risk in Mexican women. Data from a Mexican multi-center population-based case–control study ofwomen aged 35 to 69 years were analysed. A total of 1000 cases and 1074 matched controls were recruited between 2004 and 2007. Information on hormonal therapy was collected through a structured questionnaire. Results were analysed using conditional logistic regression models. Overall, HC were used by 422/891 (47.3%) premenopausal women and HRT was used by 220/1117 (19.7%) postmenopausal women. For HC, odds ratios (ORs) for BC were 1.11 (95% confidence interval (CI): 0.82, 1.49) for current users and 1.68 (95% CI: 0.67, 4.21) for ever-users. No clear effect of duration of use was observed. For HRT, the OR for BC was significantly increased in ever users (OR: 1.45; 95% CI: 1.01, 2.08). A non-significant increased risk was observed for combined estrogen/progestin, (OR = 1.85; 95% CI: 0.84, 4.07) whereas no effect was observed for the use of estrogen alone (OR = 1.14; 95% CI: 0.68, 1.91). Our results indicate that, HC had a non-significant effect on the risk of pre-menopausal BC, but suggested that injected contraceptives may slightly increase the risk, whereas HRT had a significant effect on post-menopausal BC in this population. This study provides new information about the effects of HC and HRT on BC risk in a Mexican population, which may be of relevance for the population of Latin America as a whole. 相似文献
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Fiona Wegman F. Cumhur Öner Wouter J.A. Dhert 《Biotechnology & genetic engineering reviews》2013,29(2):206-220
The possibilities of using gene therapy for bone regeneration have been extensively investigated. Improvements in the design of new transfection agents, combining vectors and delivery/release systems to diminish cytotoxicity and increase transfection efficiencies have led to several successful in vitro, ex vivo and in vivo strategies. These include growth factor or short interfering ribonucleic acid (siRNA) delivery, or even enzyme replacement therapies, and have led to increased osteogenic differentiation and bone formation in vivo. These results provide optimism to consider use in humans with some of these gene-delivery strategies in the near future. 相似文献
55.
56.
Fiona Magowan 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(3):325-327
Jungayi—Caring for Country Jungayi—Caring for Country. Directed and edited by Penny McDonald; produced by Claire Smith; camera: Warwick Thorne; sound: George Hanna. English narration and subtitling of Jawoyn and Ngalkbon languages. Distributed by International Federation of Rock Art Organisations, PO. Box 216, Caulfield South, Vic., Australia 3162.1992, 27 minutes, color, VHS‐NTSC and VHS‐PAL, sale U.S. $32. 相似文献
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58.
Lee A. Rollins Angela T. Moles Serena Lam Robert Buitenwerf Joanna M. Buswell Claire R. Brandenburger Habacuc Flores‐Moreno Knud B. Nielsen Ellen Couchman Gordon S. Brown Fiona J. Thomson Frank Hemmings Richard Frankham William B. Sherwin 《Ecology and evolution》2013,3(13):4501-4517
Some introduced populations thrive and evolve despite the presumed loss of diversity at introduction. We aimed to quantify the amount of genetic diversity retained at introduction in species that have shown evidence of adaptation to their introduced environments. Samples were taken from native and introduced ranges of Arctotheca populifolia and Petrorhagia nanteuilii. Using microsatellite data, we identified the source for each introduction, estimated genetic diversity in native and introduced populations, and calculated the amount of diversity retained in introduced populations. These values were compared to those from a literature review of diversity in native, confamilial populations and to estimates of genetic diversity retained at introduction. Gene diversity in the native range of both species was significantly lower than for confamilials. We found that, on average, introduced populations showing evidence of adaptation to their new environments retained 81% of the genetic diversity from the native range. Introduced populations of P. nanteuilii had higher genetic diversity than found in the native source populations, whereas introduced populations of A. populifolia retained only 14% of its native diversity in one introduction and 1% in another. Our literature review has shown that most introductions demonstrating adaptive ability have lost diversity upon introduction. The two species studied here had exceptionally low native range genetic diversity. Further, the two introductions of A. populifolia represent the largest percentage loss of genetic diversity in a species showing evidence of substantial morphological change in the introduced range. While high genetic diversity may increase the likelihood of invasion success, the species examined here adapted to their new environments with very little neutral genetic diversity. This finding suggests that even introductions founded by small numbers of individuals have the potential to become invasive. 相似文献
59.
Cleopatra K. Mugyenyi Salenna R. Elliott Fiona J. McCallum Robin F. Anders Kevin Marsh James G. Beeson 《PloS one》2013,8(7)
Background
Antibodies to P. falciparum apical membrane protein 1 (AMA1) may contribute to protective immunity against clinical malaria by inhibiting blood stage growth of P. falciparum, and AMA1 is a leading malaria vaccine candidate. Currently, there is limited knowledge of the acquisition of strain-specific and cross-reactive antibodies to AMA1 in humans, or the acquisition of invasion-inhibitory antibodies to AMA1.Methodology/Findings
We examined the acquisition of human antibodies to specific polymorphic invasion-inhibitory and non-inhibitory AMA1 epitopes, defined by the monoclonal antibodies 1F9 and 2C5, respectively. Naturally acquired antibodies were measured in cohorts of Kenyan children and adults. Antibodies to the invasion-inhibitory 1F9 epitope and non-inhibitory 2C5 epitope were measured indirectly by competition ELISA. Antibodies to the 1F9 and 2C5 epitopes were acquired by children and correlated with exposure, and higher antibody levels and prevalence were observed with increasing age and with active P. falciparum infection. Of note, the prevalence of antibodies to the inhibitory 1F9 epitope was lower than antibodies to AMA1 or the 2C5 epitope. Antibodies to AMA1 ectodomain, the 1F9 or 2C5 epitopes, or a combination of responses, showed some association with protection from P. falciparum malaria in a prospective longitudinal study. Furthermore, antibodies to the invasion-inhibitory 1F9 epitope were positively correlated with parasite growth-inhibitory activity of serum antibodies.Conclusions/Significance
Individuals acquire antibodies to functional, polymorphic epitopes of AMA1 that may contribute to protective immunity, and these findings have implications for AMA1 vaccine development. Measuring antibodies to the 1F9 epitope by competition ELISA may be a valuable approach to assessing human antibodies with invasion-inhibitory activity in studies of acquired immunity and vaccine trials of AMA1. 相似文献60.
Nadezda V. Kovalevskaya Charlotte Whicher Timothy D. Richardson Craig Smith Jana Grajciarova Xocas Cardama José Moreira Adrian Alexa Amanda A. McMurray Fiona G. G. Nielsen 《PLoS biology》2016,14(3)
There is no unified place where genomics researchers can search through all available raw genomic data in a way similar to OMIM for genes or Uniprot for proteins. With the recent increase in the amount of genomic data that is being produced and the ever-growing promises of precision medicine, this is becoming more and more of a problem. DNAdigest is a charity working to promote efficient sharing of human genomic data to improve the outcome of genomic research and diagnostics for the benefit of patients. Repositive, a social enterprise spin-out of DNAdigest, is building an online platform that indexes genomic data stored in repositories and thus enables researchers to search for and access a range of human genomic data sources through a single, easy-to-use interface, free of charge. 相似文献