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In the bid to exploit the synergy in mixed metal matrix that enhances substrate binding affinity, a composite reactive material (GLT) was prepared using lateritic soil and Gastropod shell as precursors. The defluoridation efficiency of the GLT was studied in laboratory grade fluoride contaminated water and groundwater matrix. Using experimental evidences, insight into the underlying defluoridation mechanisms of GLT was provided. The monolayer adsorption capacity (qm, mg/g) of the GLT (43.7 mg/g) was higher than that of any of the precursors (i.e. lateritic soil (qm = 2.8 mg/g) and Gastropod shell (qm = 19.8 mg/g)), which confirmed the synergistic effect of the constituents of the composite. Premised on the results of kinetic analysis, the Gibbs (?G) free energy value of formation of insoluble metal fluoride and the results of the evaluation of the effects of water chemistry on the fluoride removal efficiency of the GLT, mechanism of the defluoridation process was found to be a combination of adsorption (via ion exchange or outer sphere complexation) and precipitation reaction. Relative to the performance of the GLT in laboratory grade water, the GLT was also effective in groundwater but the value of the Langmuir monolayer adsorption capacity (qm mg/g) was lower in the groundwater system (29.76 mg/g) than in the laboratory grade water system (43.7 mg/g). The leached constituents of the GLT enhanced the values of the pH, electrical conductivity and the total dissolved solids of the treated water.  相似文献   
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Purpose

A region of chromosome 22 which includes APOL1 and MYH9 genes was recently identified as a risk locus for non-diabetic forms of kidney disease, including idiopathic and HIV-associated focal segmental glomerular sclerosis and kidney disease clinically attributed to hypertension among African Americans. The purposes of the current study were, therefore, to examine the frequency of these variants and to determine whether they are associated with chronic kidney disease (CKD) among native Africans.

Methods

To investigate the possible evidence of association between variants in these genes and non-diabetic CKD among West Africans, we performed a case/control analysis in a sample of 166 Nigerians without history of European admixture. Our study included a total of 9 variants on APOL1 (n = 4) and MYH9 (n = 5) genes.

Results

We observed significantly strong associations with previously reported APOL1 variants rs73885319 and rs60910145, and their two-allele “G1” haplotype (P < 0.005). We did not observe significant evidence of association between non-diabetic CKD and any of the MYH9 variants or haplotypes after accounting for multiple testing in our sample.

Conclusions

In conclusion, APOL1 risk variants are associated with non-diabetic forms of CKD among Nigerians of Yoruba ethnicity. Further information on APOL1/MYH9 variants may lead to screening programs, which could lead to earlier detection and interventions for non-diabetic kidney disease.  相似文献   
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A case of advanced heterotopic pregnancy in which an ovarian pregnancy caused obstructed labour with incomplete uterine rupture is presented. A live baby that weighed 3.25 kg was delivered at caesarean section. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. The left ovarian mass contained a fetus papyraceus of about 24 weeks gestation.  相似文献   
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Pediculocidal and scabicidal properties of Lippia multiflora essential oil   总被引:2,自引:0,他引:2  
The essential oil from the leaves of Lippia multiflora Moldenke (Verbenaceae) was tested for its pediculocidal and scabicidal activites against bodylice, headlice and scabies' mites. The 'knockdown' times obtained for bodylice and headlice using lippia oil preparations were comparatively shorter than those obtained using benzyl benzoate and Delvap Super, a brand of dichlorvos. The lethal effect of the lippia oil on headlice was increased when applied in an enclosed system that prevented volatilization of the oil while allowing maximum contact of the vapour with the headlice. A 20% v/v preparation of lippia oil applied to scabietic subjects for 5 consecutive days gave 100% cure compared with 87.5% cure obtained for benzyl benzoate preparation of the same concentration. The GC-MS analysis of oil revealed, among others, the presence of terpineol, alpha- and beta-pinene which are known to be lethal to body and headlice.  相似文献   
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There has been considerable recent research into protein based Streptococcus pneumoniae vaccines as alternatives to the existing capsular antigen vaccines. PiuA and PiaA (formerly Pit1A and Pit2A) are recently identified lipoprotein components of S. pneumoniae iron uptake ABC transporters which are required for full virulence and are likely to be expressed on the surface of the bacterial cell membrane. We investigated the efficacy of recombinant PiuA and PiaA proteins at eliciting protective immunity in mice against systemic infection with S. pneumoniae. Both recombinant PiuA and PiaA generated antibody responses that cross-reacted with each other but not with pneumolysin and reacted with identical proteins from nine different S. pneumoniae serotypes. Mice immunized with recombinant PiuA and PiaA were protected against systemic challenge to a degree similar to those immunized with an existing protein vaccine candidate, PdB (a genetically modified pneumolysin toxoid). Immunization with a combination of both PiuA and PiaA resulted in additive protection and was highly protective against systemic infection with S. pneumoniae. PiuA and PiaA are therefore promising additional candidates for a novel S. pneumoniae vaccine using protein antigens.  相似文献   
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CONTEXT: Alzheimer disease (AD) represents a major and increasing public health problem. If populations were identified with significantly lower or higher incidence rates of AD, the search for risk factors in the genesis of AD could be greatly enhanced. OBJECTIVE: To compare incidence rates of dementia and AD in 2 diverse, elderly community-dwelling populations. DESIGN: The Indianapolis-Ibadan Dementia Project, a longitudinal, prospective population-based study consisting of a baseline survey (1992-1993) and 2 subsequent follow-up waves after 2 years (1994-1995) and 5 years (1997-1998). Each wave followed a 2-stage design, with an in-home screening interview followed by a full diagnostic workup of a subsample of participants based on screening performance. SETTING AND PARTICIPANTS: A total of 2459 community-dwelling Yoruba residents of Ibadan, Nigeria, without dementia, and 2147 community-dwelling African American residents of Indianapolis, Ind, without dementia (all aged 65 years or older). The cohorts were followed up for a mean of 5.1 years and 4.7 years, respectively. MAIN OUTCOME MEASURES: Incident cases of dementia and AD in each of the 2 populations. RESULTS: The age-standardized annual incidence rates were significantly lower among Yoruba than among African Americans for dementia (Yoruba, 1.35% [95% confidence interval [CI], 1.13%-1.56%]; African Americans, 3.24% [95% CI, 2.11%-4.38%]) and for AD (Yoruba, 1.15% [95% CI, 0.96%-1.35%]; African Americans, 2.52% [95% CI, 1.40%-3.64%]). CONCLUSION: This is the first report of incidence rate differences for dementia and AD in studies of 2 populations from nonindustrialized and industrialized countries using identical methods and the same group of investigators in both sites. Further explorations of these population differences may identify potentially modifiable environmental or genetic factors to account for site differences in dementia and AD.  相似文献   
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We determined the prevalence of dementia in a cohort of 2494 elderly Nigerians residents in Idikan Community, Ibadan, Nigeria. We utilized the Community Screening Instrument for Dementia to select subjects for clinical assessment in the second stage. The findings were compared with those of 2212 African Americans living in Indianapolis, studied simultaneously using similar methodology. The overall age-adjusted prevalence rates of dementia and Alzheimer's disease in Ibadan were 2.29% and 1.41%, respectively. These rates were much lower than the respective values of 8.24% and 6.24% obtained for African Americans. In Ibadan, Alzheimer's disease accounted for 64.3% of the cases, with old age and female gender being the significant risk factors, whilst 'living with others' appeared to be protective (P < 0.05). Amongst African Americans, on the other hand, old age, rural living below the age of 19 years, low educational attainment and family history of dementia were the risk factors. There was a lack of association between Alzheimer's disease and possession of the apolipoprotein E epsilon4 allele in the Nigerian sample, unlike the finding in African Americans, where significant association was shown. In addition, the frequencies of the vascular risk factors investigated were lower in Nigerians. Our results showed lower prevalence of dementia and Alzheimer's disease in Nigerians, compared with African Americans. There was no association between Alzheimer's disease and apolipoprotein E (epsilon4 allele) in the former. The differences in the frequencies of vascular risk factors between Nigerian subjects and African Americans would suggest involvement of environmental factors in disease process.  相似文献   
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