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81.
Aims
To assess parental attitudes towards type 1 diabetes clinical trials (T1DCTs) and factors that impact willingness to enroll their children with and without diabetes.Methods
A cross-sectional survey of parents of children with type 1 diabetes was administered at an academic clinic and a diabetes educational event.Results
Survey response rate was 36%. Of 166 participating parents, 76% were aware of T1DCTs. More parents reported willingness to enroll children with diabetes (47%) than unaffected children (36%). Only 18% recalled being asked to enroll their children, and of these, 60% agreed to enroll at least some of those times. Less than 30% were comfortable with placebos. Factors predicting willingness to enroll children with diabetes included healthcare provider trust, comfort with consent by proxy, low fear of child being a “guinea pig,” and comfort with placebo. Factors predicting willingness to enroll unaffected children were provider trust, comfort with consent by proxy, comfort with placebo, and perceived ease of understanding T1DCT information.Conclusions
Parents report moderate willingness to enroll children in T1DCTs. Willingness is diminished by common trial methodologies. Although most parents recalled receiving trial-related information, significantly fewer recalled being asked to participate. Efforts to optimize effective communication around identified areas of parental concern may increase T1DCT participation. 相似文献82.
JJ Schellenberg TJ Dumonceaux JE Hill J Kimani W Jaoko C Wachihi JN Mungai M Lane KR Fowke TB Ball FA Plummer 《PloS one》2012,7(7):e41217
The common but poorly understood condition known as bacterial vaginosis (BV) increases vulnerability to HIV infection and is associated with the absence of H(2)O(2)-producing Lactobacillus. Vaginal lactic acid bacteria (LAB) produce anti-HIV factors such as organic acids and hydrogen peroxide (H(2)O(2)), and may bind and inactivate HIV particles during scavenging of mannose. These factors define potential criteria for initial selection of candidate probiotics to block heterosexual transmission of HIV. Therefore, the primary goal of this study was to characterize acid production on mannose and H(2)O(2) production in vaginal isolates from Canadian adolescents (192 isolates, 16 individuals) and commercial sex workers in Nairobi, Kenya (576 isolates, 96 individuals). Selection of isolates from H(2)O(2)-detecting media suggested an idiosyncratic individual-level profile and extensive phenotypic diversity, including the identification of a subset of "double-strong" acid- and H(2)O(2)-producers with phenotypes similar to well-characterized probiotic strains. Molecular fingerprinting of all isolates by capillary electrophoresis of 16S-23S rRNA interspacer amplicons was coupled with chaperonin-60 universal target (cpn60 UT) sequencing in a subset, tentatively identifying 96% of isolates although only 19% were sequenced. Most isolates belonged to Lactobacillus, Streptococcus, Bifidobacterium or Gardnerella, with a total of 37 species in 15 genera, as well as 5 potentially novel organisms, identified in this study. This sensitivity was likely enhanced by phenotype-based selection on two chromogenic media formulations. Identification of double-strong isolates may provide a rational basis for selection and further characterization of vaginal probiotics, with potential application as part of HIV prevention initiatives in western Canada and East Africa. 相似文献
83.
Forde T Kutz S De Buck J Warren A Ruckstuhl K Pybus M Orsel K 《Journal of wildlife diseases》2012,48(1):1-11
The role that wildlife may play in the transmission of Mycobacterium avium subspecies paratuberculosis (Map), the causative agent of Johne's disease (JD), and the potential consequences of infection in these populations are being given increasing consideration. A yearling male Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from southwestern Alberta, Canada, was found infected with Map in August 2009. Clinical signs of emaciation and diarrhea and histologic findings of diffuse granulomatous enteritis of the distal ileum, lymphadenitis of the mesenteric lymph nodes, and lymphangitis of the ileum were similar to previously described cases of JD in bighorn sheep. Infection with Map was confirmed by bacterial isolation through fecal culture, acid-fast staining, and polymerase chain reaction (PCR) of IS900. The Map1506 gene was sequenced, and the isolate was identified as a Cattle (Type II) strain. In a follow-up herd-level survey, three of 44 fecal samples (7%) from individual bighorn sheep from the same herd as the index case were PCR-positive and identified as Type II Map strains. Twenty-five samples from a distant bighorn population were negative. Additional strain typing of the isolates from the index case and the positive fecal samples was done by sequencing three discriminatory short sequence repeat (SSR) regions. All four SSR profiles differed from one another, suggesting multiple introductions or a long-existing circulation of Map within this bighorn population. Detailed molecular analyses are essential for understanding and managing diseases at the wildlife-livestock interface. 相似文献
84.
Van Trappen S Mergaert J Van Eygen S Dawyndt P Cnockaert MC Swings J 《Systematic and applied microbiology》2002,25(4):603-610
Microbial mats, growing in Antarctic lakes constitute unique and very diverse habitats. In these mats microorganisms are confronted with extreme life conditions. We isolated 746 bacterial strains from mats collected from ten lakes in the Dry Valleys (lakes Hoare and Fryxell), the Vestfold Hills (lakes Ace, Druzhby, Grace, Highway, Pendant, Organic and Watts) and the Larsemann Hills (lake Reid), using heterotrophic growth conditions. These strains were investigated by fatty acid analysis, and by numerical analysis, 41 clusters, containing 2 to 77 strains, could be delineated, whereas 31 strains formed single branches. Several fatty acid groups consisted of strains from different lakes from the same region, or from different regions. The 16S rRNA genes from 40 strains, representing 35 different fatty acid groups were sequenced. The strains belonged to the alpha, beta and gamma subclasses of the Proteobacteria, the high and low percent G+C Gram-positives, and to the Cytophaga-Flavobacterium-Bacteroides branch. For strains representing 16 fatty acid clusters, validly named nearest phylogenetic neighbours showed pairwise sequence similarities of less than 97%. This indicates that the clusters they represent, belong to taxa that have not been sequenced yet or as yet unnamed new taxa, related to Alteromonas, Bacillus, Clavibacter, Cyclobacterium, Flavobacterium, Marinobacter, Mesorhizobium, Microbacterium, Pseudomonas, Saligentibacter, Sphingomonas and Sulfitobacter. 相似文献
85.
86.
Background A cohort of SIV‐infected macaques had been used to investigate the effect of dietary supplement, immune status, SIV/AIDS disease progression and serum micronutrients levels on spontaneous acquisition of Enterocytozoon bieneusi infection in SIV‐infected macaques. Methods Twenty‐four SIV‐infected macaques were randomized into 2 groups. One group received a vitamin/mineral supplementation and a second group received a placebo. Both groups were examined for E. bieneusi infection. Results SIV‐infected macaques were more prone to acquire E. bieneusi with the progression of SIV/AIDS, and the increased shedding of infectious spores was directly associated with decreased CD4 lymphocyte and increased circulating SIV, in both supplemented and unsupplemented groups of animals. Dietary supplementation, body composition factors and serum micronutrients levels however had no association with the acquisition of E. bieneusi infection in these animals. Conclusions Acquisition of E. bieneusi infection is related to SIV disease progression, CD4 counts and viral load but independent of changes in body composition and serum micronutrient levels. 相似文献
87.
George M. Branch Colin G. Attwood Dianne Gianakouras Margo L. Branch 《Polar Biology》1993,13(1):23-34
Summary Benthic communities at the sub-Antarctic Prince Edward Islands were sampled qualitatively with an epi-benthic sled at 57 stations over a five year period. Additional information on these communities was obtained from replicate underwater photographs. In total, 546 macrofaunal species were found. Despite the extreme isolation and geological youth of the islands, there seems to have been a diverse colonisation. A cluster-analysis based on species abundance aggregated most stations into 8 groups. Each of these groups had a unique depth and substratum combination. Thourella variabilis (Octocoralea), and Cabarea darwinii (Bryozoa) characterised deep rocky assemblages and Serpula vermicularis, Lanice conchilega (Polychaeta) and Magellania kerguelenensis (Brachiopoda) characterised soft substrata. Indicator species separating each of the 8 clusters are given. Trends in percentage cover and densities of major taxa with respect to depth and substratum, as shown by photographs, are described. Deep, rocky substrata were dominated by Porifera, Bryozoa and Cnidaria, while soft-substrata were dominated by Polychaeta, Bivalvia and Brachiopoda. Errant forms consisted predominantly of Echinodermata, with Crustacea being important in shallower habitats. Filter-feeders dominated the benthos of the islands in all habitats. 相似文献
88.
RAGE mRNA expression in the diabetic mouse kidney 总被引:1,自引:0,他引:1
Ziyadeh Fuad N. Cohen Margo P. Guo Jia Jin Yulin 《Molecular and cellular biochemistry》1997,170(1-2):147-152
Receptors for advanced glycation end products (RAGE), which bind and internalize AGE-modified proteins formed from oxidation and other products of the nonenzymatic glycation reaction, have been mechanistically implicated in the development of the chronic complications of diabetes. In the present experiments, we sought evidence for the participation of RAGE in diabetic nephropathy by analysis of steady state levels of mRNA encoding RAGE in the renal cortex of a well-defined animal model (the db/db mouse) that develops renal pathology similar to that found in human diabetes. In these animals, increased AGE-product formation was confirmed by measurement of fluorescence in serum and renal cortex proteins. Renal involvement was confirmed by demonstration of increased urine albumin excretion and elevated serum creatinine concentrations relative to nondiabetic (db/m) littermate controls. Despite elevated concentrations of circulating and tissue AGE-modified proteins, the level of RAGE mRNA expression in renal cortex of diabetic mice did not significantly differ from that in nondiabetic littermate controls. The findings militate against changes in RAGE expression in the pathogenesis of renal abnormalities in this animal model. 相似文献
89.
90.
Streptococcus tangierensis sp. nov. and Streptococcus cameli sp. nov., two novel Streptococcus species isolated from raw camel milk in Morocco 总被引:1,自引:0,他引:1