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51.
Background
Because of its propensity to sequester in the placental intervillous space, Plasmodium falciparum can evade detection by peripheral smear in women with placental malaria (PM). We evaluated host biomarkers as potential indicators of occult PM infections.Methods and Findings
Using a case-control design, we evaluated the ability of biomarkers to identify PM in the absence of circulating peripheral parasites (n = 24) compared to placental smear-negative controls (n = 326). We measured levels of biomarkers (C3a, C5a, CRP, angiopoietin-1, angiopoietin-2, sTie-2, sEndoglin, VEGF, sFlt-1, tissue factor, and leptin) in maternal peripheral plasma at delivery. Using ROC curve analysis, we assessed the ability of clinical parameters and biomarkers to accurately detect PM infections identified by placental smear. We show that decreases in sFlt-1 and leptin and increases in CRP were associated with occult PM infections (p<0.01) and correlated with placental parasitaemia (p<0.01). Individually, all markers had moderate ability to diagnose occult PM infections with areas under the ROC between 0.62 and 0.72. In order to improve diagnostic performance, we generated simple scoring systems to identify PM infections using either a clinical score (0–2), a biomarker score (0–3) or a clinical plus biomarker score (0–5). The combinatorial model that incorporated both clinical parameters and biomarkers had an area under curve (AUC) of 0.85 (95% CI, 0.81-0.89), which was significantly better at identifying occult PM infections than the clinical score alone (p = 0.001).Conclusion
These data suggest that host biomarkers in the maternal peripheral blood may improve the detection of PM in the absence of peripheral parasitaemia. 相似文献52.
53.
Background
The growth of new blood vessels in adult life requires the initiation of endothelial cell migration and proliferation from pre-existing vessels in addition to the recruitment and differentiation of circulating endothelial progenitor cells. Signals emanating from growth factors and the extracellular matrix are important in regulating these processes. 相似文献54.
55.
56.
Structural basis of membrane invagination by F-BAR domains 总被引:1,自引:0,他引:1
Frost A Perera R Roux A Spasov K Destaing O Egelman EH De Camilli P Unger VM 《Cell》2008,132(5):807-817
BAR superfamily domains shape membranes through poorly understood mechanisms. We solved structures of F-BAR modules bound to flat and curved bilayers using electron (cryo)microscopy. We show that membrane tubules form when F-BARs polymerize into helical coats that are held together by lateral and tip-to-tip interactions. On gel-state membranes or after mutation of residues along the lateral interaction surface, F-BARs adsorb onto bilayers via surfaces other than their concave face. We conclude that membrane binding is separable from membrane bending, and that imposition of the module's concave surface forces fluid-phase bilayers to bend locally. Furthermore, exposure of the domain's lateral interaction surface through a change in orientation serves as the crucial trigger for assembly of the helical coat and propagation of bilayer bending. The geometric constraints and sequential assembly of the helical lattice explain how F-BAR and classical BAR domains segregate into distinct microdomains, and provide insight into the spatial regulation of membrane invagination. 相似文献
57.
Yankura DJ Conroy MB Hess R Pettee KK Kuller LH Kriska AM 《Obesity (Silver Spring, Md.)》2008,16(10):2259-2265
Weight loss improves health-related quality of life (HRQoL). However, regain after loss is common; little is known about the impact of weight regain on HRQoL in postmenopausal women. Woman on the Move through Activity and Nutrition (WOMAN) is a randomized lifestyle intervention trial of diet, physical activity, and weight loss in 508 postmenopausal women aged 52-62 years. This analysis focused on the women who lost > or =5 lb during the initial phase of the study, baseline to 6 months (n = 248). This cohort was divided into three groups based on subsequent weight change between 6 and 18 months: weight loss (WL; > or =5 lb loss), weight stable (WS; <+/-5 lb change), and weight regain (WR; > or =5 lb gain). HRQoL was measured at baseline, 6, and 18 months using the Short Form-36. Of the 248 women studied, 51 (21%) continued to lose weight after initial weight loss, while 127 (51%) maintained a stable weight, and 70 (28%) regained weight. Between baseline and 6 months, women in WR group had decreased mental health and social-functioning scores, while the WL and WS groups improved in these subscales. Between baseline and 18 months, energy improved most significantly in those with continued weight loss (P = 0.0003). Weight loss was correlated with a small to moderate improvement in perceived general health and energy, which was reversed by weight gain. Further study is needed to investigate the impact of a decline in mental health and social functioning on future weight regain. 相似文献
58.
W C Conroy 《Plastic and reconstructive surgery》1974,54(6):683-684
59.
Advanced computer graphics technology reveals cortical asymmetry in endocasts of rhesus monkeys 总被引:1,自引:0,他引:1
D Falk J Cheverud M W Vannier G C Conroy 《Folia primatologica; international journal of primatology》1986,46(2):98-103
Lengths of cortical sulci were measured on ten endocranial casts (endocasts) from skulls of rhesus monkeys, using advanced computer technology that permits analysis and imaging of surface morphology in three dimensions. Sulcal lengths were compared in left and right hemispheres and, contrary to earlier reports, the length of the left Sylvian fissure was found to be significantly longer than its right counterpart, as is the case for chimpanzees and humans. This asymmetry in humans is thought to be associated with asymmetrical representation of language functions in the left hemisphere and, although this report is the first to demonstrate a significantly longer left Sylvian fissure in rhesus monkeys, our results are in keeping with psychophysical evidence that suggests that Macaca is left hemisphere dominant for perception of meaningful vocalizations. We attribute the difference between our findings and previous reports to the sensitivity of the new computer technology used to collect data from endocasts. 相似文献
60.