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1.
Hyperlipidemia is a major risk factor in etiology of cardiovascular disease. Previous studies have shown association between vegetarian diet and low total serum cholesterol as well as LDL-cholesterol which is a pointer to low risk of cardiovascular disease. Dietary fiber, antioxidants and other classes of nutrients have been reported to ameliorate cardiovascular risk factors. Fruits and vegetables being rich sources of fiber and antioxidants have been the focus in intervention studies. The current work reports the effect local fruits and vegetables on cardiovascular risk factors in African hypertensive subjects in an 8 week study. Though there was no significant difference in the Body Mass Index and HDL-cholesterol at the end of the eighth week, there were significant reductions (P < 0.05) in serum triglycerides (125.87 ± 6.0 to108.27 ± 5.49 mgdL-1); total serum cholesterol (226.60 ± 6.15 to 179.20 ± 5.78) and LDL-cholesterol (135.69 ± 5.56 to 93.07 ± 7.18 mgdL-1). We concluded that consumption of combination of local fruits and vegetables may reduce the incidence of cardiovascular risk factors in Africans.  相似文献   
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A cross-sectional study of female condom awareness, usage and concerns among the female undergraduates of the University of Ibadan was conducted in September 2004. The results of 850 out of the 879 female students interviewed were used for analysis (96.6%). Over 80% had knowledge of the female condom as a form of modern contraception and the majority of them learnt about it through the mass media (39.9%) and health workers (34.4%). However, only 11.3% had ever used the female condom, with most (40%) using it to prevent both unwanted pregnancy and sexually transmitted infections including HIV (STI/HIV). The sexual partners' approval was appreciable, accounting for about 42.7% among those that had experience of the female condom usage. Major concerns mentioned such as difficulty of inserting it into the vagina and lack of sexual satisfaction, were not different from those in earlier studies. The result of this study looks promising judging from a high awareness level of the female condom, even though its usage is low. The female condom may be an alternative strategy to combat unsafe sexual practises and its sequelae in a country like Nigeria that is male dominated.  相似文献   
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Mice immunized with two different cryptococcal antigen preparations, one a soluble culture filtrate antigen (CneF) in complete Freund’s adjuvant (CFA) and the other heat-killed Cryptococcus neoformans cells (HKC), develop two different profiles of activated T cells. CneF-CFA induces CD4+ T cells responsible for delayed-type hypersensitivity (DTH) reactivity and for amplification of the anticryptococcal DTH response, whereas HKC induce CD4+ and CD8+ T cells involved in anticryptococcal DTH reactivity and activated T cells which directly kill C. neoformans cells. The main purpose of this study was to assess the level of protection afforded by each of the two different T-cell profiles against challenge with viable C. neoformans cells, thereby identifying which activated T-cell profile provides better protection. CBA/J mice immunized with CneF-CFA had significantly better protective responses, based on better clearance of C. neoformans from tissues, on longer survival times, and on fewer and smaller lesions in the brain, than HKC-immunized mice or control mice similarly infected with C. neoformans. Both immunization protocols induced an anticryptococcal DTH response, but neither induced serum antibodies to glucuronoxylmannan, so the protection observed in the CneF-CFA immunized mice was due to the activated T-cell profile induced by that protocol. HKC-immunized mice, which displayed no greater protection than controls, did not have the amplifier cells. Based on our findings, we propose that the protective anticryptococcal T cells are the CD4+ T cells which have been shown to be responsible for DTH reactivity and/or the CD4+ T cells which amplify the DTH response and which have been previously shown to produce high levels of gamma interferon and interleukin 2. Our results imply that there are protective and nonprotective cell-mediated immune responses and highlight the complexity of the immune response to C. neoformans antigens.  相似文献   
4.
We have constructed haplotypes based on normal variation at six polymorphic sites-five single nucleotide polymorphisms (SNPs) and one short tandem repeat polymorphism (STRP)-at the RET locus for samples of normal individuals from 32 populations distributed across the major continental regions of the world. The haplotyped system spans 41.6 kilobases and encompasses most of the coding region of the gene. All of the markers are polymorphic in all regions of the world and in most individual populations. Expected heterozygosities for the six-site haplotypes range from 82 to 94% for all populations studied except for two Amerindian groups from the Amazon basin at 61 and 76%. Individual populations had from four to eight haplotypes with frequencies exceeding 5%. In general, African, southwest Asian and European groups have the highest numbers of total and of commonly occurring haplotypes; the lowest numbers are observed in Amerindian populations. Overall linkage disequilibrium (LD) for the five SNP sites was very significant (P相似文献   
5.
Although vitamin D (vD) deficiency is common in breastfed infants and their mothers during pregnancy and lactation, a standardized global comparison is lacking. We studied the prevalence and risk factors for vD deficiency using a standardized protocol in a cohort of breastfeeding mother-infant pairs, enrolled in the Global Exploration of Human Milk Study, designed to examine longitudinally the effect of environment, diet and culture. Mothers planned to provide breast milk for at least three months post-partum and were enrolled at four weeks postpartum in Shanghai, China (n = 112), Cincinnati, Ohio (n = 119), and Mexico City, Mexico (n = 113). Maternal serum 25(OH)D was measured by radioimmunoassay (<50 nmol/L was categorized as deficient). Serum 25(OH)D was measured in a subset of infants (35 Shanghai, 47 Cincinnati and 45 Mexico City) seen at 26 weeks of age during fall and winter seasons. Data collected prospectively included vD supplementation, season and sun index (sun exposure × body surface area exposed while outdoors). Differences and factors associated with vD deficiency were evaluated using appropriate statistical analysis. vD deficiency in order of magnitude was identified in 62%, 52% and 17% of Mexican, Shanghai and Cincinnati mothers, respectively (p < 0.001). In regression analysis, vD supplementation (p < 0.01), obesity (p = 0.03), season (p = 0.001) and sites (p < 0.001) predicted maternal vD status. vD deficiency in order of  magnitude was found in 62%, 28%, and 6% of Mexican, Cincinnati and Shanghai infants, respectively (p < 0.001). Season (p = 0.022), adding formula feeding (p < 0.001) and a higher sun index (p = 0.085) predicted higher infant vD status. vD deficiency appears to be a global problem in mothers and infants, though the prevalence in diverse populations may depend upon sun exposure behaviors and vD supplementation. Greater attention to maternal and infant vD status starting during pregnancy is warranted worldwide.  相似文献   
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Cyclosporine (CYA), a common immuno-suppressant drug that is used in organ transplants, is associated with nephrotoxic effects. Scientific exploration of natural products of plant origin should be considered; especially, in a world with increasing prevalence of kidney diseases. Effects of ginger polyphenols (GP) in Wistar rats with CYA-induced perturbations in electrolyte balance and kidney function was determined. Fifty Wistar rats were recruited for this study such that graded doses of GP were administered following CYA-induced kidney injury and comparisons were made against control and toxic groups at p?<?0.05. Distilled water, CYA (50?mg/kg p.o. for 10 days) and GP (100, 200 and 400?mg/kg p.o. for 21 days) were administered to the rats at 0.2?ml/100?g. CYA administration induced kidney injury as characterized by significant deleterious alterations in plasma and urine levels of creatinine, urea, Na+ and K+ electrolyte balance as well as creatinine clearance. Also, there was a significant derangement in feeding pattern and relative kidney weight. Using GSH and SOD as antioxidant indicators, there was significant disturbance of the anti-oxidant system while histopathological results showed evidence of interstitial vacuolations with atrophic glomeruli. These conditions were significantly attenuated (p?<?0.05) following administration of graded doses of GP. It was, therefore, concluded that GP could potentially be a therapeutic choice for patients with CYA-induced kidney injury.  相似文献   
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Diagnosis of articular cartilage pathology in the early disease stages using current clinical diagnostic imaging modalities is challenging, particularly because there is often no visible change in the tissue surface and matrix content, such as proteoglycans (PG). In this study, we propose the use of near infrared (NIR) spectroscopy to spatially map PG content in articular cartilage. The relationship between NIR spectra and reference data (PG content) obtained from histology of normal and artificially induced PG-depleted cartilage samples was investigated using principal component (PC) and partial least squares (PLS) regression analyses. Significant correlation was obtained between both data (R2 = 91.40%, p<0.0001). The resulting correlation was used to predict PG content from spectra acquired from whole joint sample, this was then employed to spatially map this component of cartilage across the intact sample. We conclude that NIR spectroscopy is a feasible tool for evaluating cartilage contents and mapping their distribution across mammalian joint.OCIS codes: (170.6510) Spectroscopy, tissue diagnostics; (170.6935) Tissue characterization; (170.3880) Medical and biological imaging  相似文献   
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