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41.
Pepper crops in Morocco formerly thought to be free from attack by Verticillium were found to be susceptible to this pathogen. Verticillium wilt of pepper was observed in plots where the crop was cultivated in rotation with tomatoes. Strains of Verticillium isolated from pepper possessed different morphological and pathogenic characteristics.  相似文献   
42.
AIMS: To evaluate the bacteriological quality of skin moisturizing products in the South-west part of Nigeria and study factors predisposing their bacterial contamination under tropical conditions. METHODS AND RESULTS: Viable counts for bacteria exceeded 10(3) cfu ml(-1) or cfu g(-1) in 8 (16.3%) commercially available creams and lotions at time of purchase. Escherichia coli (8), Pseudomonas spp. (7), Staphylococcus spp. (9) and Bacillus spp. (6) were the most commonly recovered bacteria. Following use by volunteers, the proportion of E. coli and other Gram-negative organisms recovered increased. Organic matter, particularly in the absence of preservatives, enhanced survival and growth of bacteria in creams stored under ambient tropical conditions during challenge experiments. CONCLUSIONS: Contaminated products are relatively uncommon but some products present a potential health hazard because they are unable to suppress the growth of organisms of likely faecal origin during use. SIGNIFICANCE AND IMPACT OF THE STUDY: Quality assurance during manufacture, pack size, preservative evaluation, organic matter and water content were identified as factors to be considered during the development of creams and lotions for use in tropical developing countries.  相似文献   
43.
Hsu WC  Okeke E  Cheung S  Keenan H  Tsui T  Cheng K  King GL 《PloS one》2011,6(12):e28311

Objective

Classic features of type 1 and type 2 diabetes may not apply in Asian Americans, due to shared absence of common HLA DR-DQ genotype, low prevalence of positive anti-islet antibodies and low BMI in both types of diabetes. Our objective was to characterize diabetic phenotypes in Asian Americans by clamp and clinical features.

Materials/Methods

This was a cross-sectional study conducted in a referral center. Thirty East young Asian American adult volunteers (27.6±5.5 years) with type 1, type 2 diabetes or controls underwent hyperinsulinemic euglycemic clamp to assess insulin resistance and DEXA to assess adiposity.

Results

Gender, BMI, waist/hip ratio, leptin, LDL, anti-GAD, anti-IA2 antibodies and C-reactive protein were similar among three groups. Serum C-peptide, adiponectin, free fatty acid, HDL concentrations and truncal fat by DEXA, were different between diabetic groups. Glucose disposal rate by clamp was lowest in type 2 diabetes, followed by type 1 diabetes and controls (5.43±2.70, 7.62±2.59, 8.61±2.37 mg/min/kg, respectively, p = 0.001). Free fatty acid concentration universally plummeted during steady state of the clamp procedure regardless of diabetes types in all three groups. Adipocyte fatty acid binding protein in the entire cohort (r = −0.625, p = 0.04) and controls (r = −0.869, p = 0.046) correlated best with insulin resistance, independent of BMI.

Conclusions

Type 2 diabetes in Asian Americans was associated with insulin resistance despite having low BMI as type 1 diabetes, suggesting a potential role for targeting insulin resistance apart from weight loss. Adipocyte fatty acid binding protein, strongly associated with insulin resistance, independent of adiposity in the young Asian American population, may potentially serve as a biomarker to identify at-risk individuals. Larger studies are needed to confirm this finding.  相似文献   
44.
The parasitological and histopathological effects of immunosuppression in guinea-pigs (Cavia porcellus) experimentally infected with Schistosoma haematobium were studied. A total of 16 guinea-pigs were divided into four groups (four per group): non-immunosuppressed, non-infected group (NN); immunosuppressed, non-infected group (IN); immunosuppressed, infected group (II); non-immunosuppressed, infected group (NI). The IN and II groups were immunosuppressed with 5?mg/kg prednisolone while the II and NI animals were infected with 200-300 S. haematobium cercariae. Excretion of eggs in urine/faeces, worm burden and histopathology of some vital organs of the guinea-pigs were studied. Eggs of S. haematobium were observed in the urine of the NI and II groups from 9 weeks post-infection and in faeces from 10 and 13 weeks post-infection for the NI and II groups, respectively. However, II animals excreted more viable eggs in urine and faeces than those of the NI group. Worm recovery at 14 weeks post-infection showed that NI and II guinea-pigs had more female worms than male worms and a greater proportion of worm recovery for NI animals was of immature worms. Significant differences (P?0.05). Histological changes, which were notably reactions to adult S. haematobium worms, were observed in the organs of the NI and II groups but these changes were seen more in the organs of the immunosuppressed, infected (II) than in the non-immunosuppressed, infected (NI) guinea-pigs. The results suggest that immunosuppression before infection increased worm survival and had a moderate effect on liver and bladder histology of S. haematobium infected guinea-pigs.  相似文献   
45.

Background

Hepatitis E virus (HEV) is highly endemic in several African countries with high mortality rate among pregnant women. The prevalence of antibodies to HEV in Ghana is not known. Therefore we evaluated the prevalence of anti-HEV IgG and anti-HEV IgM among pregnant women seen between the months of January and May, 2008 at the Obstetrics and Gynaecology Department, Korle-Bu Teaching Hospital, Accra, Ghana.

Results

One hundred and fifty-seven women provided blood samples for unlinked anonymous testing for the presence of antibodies to HEV. The median age of participants was 28.89 ± 5.76 years (range 13–42 years). Of the 157 women tested, HEV seroprevelance was 28.66% (45/157). Among the seropositive women, 64.40% (29/45) tested positive for anti-HEV IgM while 35.60% (16/45) tested positive to HEV IgG antibodies. HEV seroprevalence was highest (46.15%) among women 21–25 years of age, followed by 42.82% in = 20 year group, then 36.84% in = 36 year group. Of the 157 women, 75.79% and 22.92% were in their third and second trimesters of pregnancy, respectively. Anti-HEV antibodies detected in women in their third trimester of pregnancy (30.25%) was significantly higher, P < 0.05, than in women in their second trimester of pregnancy (25.0%).

Conclusion

Consistent with similar studies worldwide, the results of our studies revealed a high prevalence of HEV infection in pregnant women.  相似文献   
46.
Chromium-resistant bacteria (CRB) isolated from soils can be used to reduce toxic Cr(VI) from contaminated environments. This study assessed in vitro reduction of hexavalent Cr using a cell-free extract (CFE) of CRB isolated from soil contaminated with dichromate. One isolate, ES 29, that substantially reduced Cr(VI) was identified as a Bacillus species by 16S rRNA gene-sequence homology. The isolate reduced Cr(VI) under aerobic conditions, using NADH as an electron donor and produced a soluble Cr(VI)-reducing enzyme stimulated by copper (Cu2+). The CFE of the bacterial isolate reduced 50% of Cr(VI) in 6 h. The Cr(VI)-reduction activity of the CFE had a Km of 7.09 microM and a Vmax of 0.171 micromol min(-1) mg(-1) protein. Mercury inhibited the enzyme, but not competitively, with a Vmax of 0.143 micromol min(-1) mg(-1) protein, a Km of 7.07 microM and a Ki of 1.58 microM. This study characterizes the enzymatic reduction of Cr(VI) by Bacillus sp. ES 29 which can be used for the bioremediation of chromate.  相似文献   
47.
Extracellular cellulolytic and xylanolytic enzymes ofStreptomyces sp. EC22 were produced during submerged fermentation. The cell-free culture supernatant of the streptomycete grown on microcrystalline cellulose contained enzymes able to depolymerize both crystalline and soluble celluloses and xylans. Higher cellulase and xylanase activities were found in the cell-free culture supernatant of the strain when grown on microcrystalline cellulose than when grown on xylan. Total cellulase and endoglucanase [carboxymethyl-cellulase (CMCase)] activities reached maxima after 72 h and xylanase activity was maximal after 60h. Temperature and pH optima were 55°C and 5.0 for CMCase activity and 60°C and 5.5 for total crystalline cellulase and xylanase activities. At 80°C, approximate half-lives of the enzymes were 37, 81 and 51 min for CMCase, crystalline cellulose depolymerization and xylanase, respectively.  相似文献   
48.
Ijanikin is a typical Yoruba village in the rain forest belt area of Southern Nigeria. The childhood years in this community are fraught with the danger of numerous communicable diseases, compounded by inadequate supply of good quality foods to meet normal requirements and allow a margin of safety for the stress of infections. Overcrowding and poor ventilation in the houses are important factors in the spread of communicable diseases, while poor sanitation and deficient personal hygiene account for the heavy burden of intestinal parasitoses. Improvement in the health of this and other similar rural communities would require the provision of clean water supply, installation of essential sanitary facilities, provision of adequate food supply, and a well-planned and carefully executed health education programme.  相似文献   
49.
The genus Enterococcus belong to the genera of bacteria that produce lactic acid and can confer health benefits to living organisms. Selenium (Se) is an essential micronutrient for humans and animals. Thirty-six Enterococcus species isolated from dairy products were screened for Se(IV) sorption capacity for use as a probiotics in animal nutrition. Several isolates grew luxuriantly and significantly removed Se(IV) from Se(IV) amended medium. Two isolates, LAB 14 and LAB 18, identified by 16S rRNA gene sequence analysis as Enterococcus faecalis (98% nucleotide sequence similarity) and Enterococcus faecium (97% nucleotide sequence similarity), respectively, were selected for further studies. The two isolates grew optimally and removed selenium at initial pH 7.0. Optimum removal of Se(IV) from the medium was recorded at 25 °C. Time course studies showed that after 8 h of incubation LAB 14 and LAB 18 cultures displayed the highest biomass production and Se(IV) bioremoval and most selenite in culture depleted in 24 h. At initial concentrations of 10 mg L−1 and 60 mg L−1, E. faecium (LAB 18) removed 9.91 mg L−1 and 59.70 mg L−1, respectively after 24 h. Similar Se(IV) bioremoval capacity was recorded with E. faecalis (LAB 14). Substantial amount of Se was detected in biomass of E. faecium (0.4599 mg g−1 of dry weight) and E. faecalis (0.4759 mg g−1 of dry weight). The significant uptake and transformation of Se(IV) by the Enterococcus species observed in this study suggest that they can be used to deliver dietary Se through feed augmentation with Se(IV)-enriched Enterococcus biomass.  相似文献   
50.
Enteroaggregative E. coli (EAEC) is an established diarrhoeagenic pathotype. The association with virulence gene content and ability to cause disease has been studied but little is known about the population structure of EAEC and how this pathotype evolved. Analysis by Multi Locus Sequence Typing of 564 EAEC isolates from cases and controls in Bangladesh, Nigeria and the UK spanning the past 29 years, revealed multiple successful lineages of EAEC. The population structure of EAEC indicates some clusters are statistically associated with disease or carriage, further highlighting the heterogeneous nature of this group of organisms. Different clusters have evolved independently as a result of both mutational and recombination events; the EAEC phenotype is distributed throughout the population of E. coli.  相似文献   
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