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11.
Sensitive PCR-restriction fragment length polymorphism assay for detection and genotyping of Giardia duodenalis in human feces 总被引:3,自引:0,他引:3 下载免费PDF全文
Amar CF Dear PH Pedraza-Díaz S Looker N Linnane E McLauchlin J 《Journal of clinical microbiology》2002,40(2):446-452
An assay that uses heminested PCR-restriction fragment length polymorphism analysis for the detection and genotyping of Giardia duodenalis on the basis of polymorphism in the triose phosphate isomerase (tpi) gene was developed. This assay was evaluated with DNA extracted from purified parasite material, bacterial cultures, whole human feces containing G. duodenalis and other parasites, and their corresponding immunofluorescence-stained fecal smears on glass microscope slides. The assay was specific and discriminated between G. duodenalis assemblages A and B. RFLP analysis further distinguished two groups (designated groups I and II) within assemblage A. Among 35 DNA samples extracted from whole feces from patients with confirmed sporadic giardiasis, the tpi gene was amplified from 33 (94%). Of these, nine (27%) samples contained assemblage A group II, 21 (64%) contained assemblage B, and 3 (9%) contained a mixture of assemblage A group II and assemblage B. The tpi gene of G. duodenalis assemblage B was amplified from 21 of 24 (88%) DNA samples extracted from whole feces from patients with confirmed cases of infection in a nursery outbreak. No amplification was detected from the remaining three DNA samples. Overall, analysis of DNA extracted from material recovered from stained microscope slides identified identical G. duodenalis genotypes in 35 (65%) of the 54 samples for which a genotype was established with DNA from whole feces. The heminested PCR method developed is sensitive, simple, and rapid to perform and is applicable for the analysis of other intestinal pathogens. 相似文献
12.
Chryseomonas luteola identified as the source of serious infections in a Moroccan University Hospital 下载免费PDF全文
Chryseomonas luteola has only rarely been reported as a human bacterial pathogen. It has been shown that this organism in particular affects patients with health or indwelling disorders. Most reported cases showed septicemia, meningitis, endocarditis, or peritonitis. Two C. luteola infections observed in Morocco are described in the present study. 相似文献
13.
In vitro gene expression strategy was used for the production of polyclonal antiserum to the nucleocapsid protein (NP) of Groundnut bud necrosis virus (GBNV). The GBNV NP gene from cowpea isolate was cloned into 6x His-tagged UA cloning vector and expressed in Escherichia coli [M15] cells. The fusion protein was detected in insoluble fraction and was purified by using Ni-NTA agarose resin. The purified 6x His-fusion protein (32 kDa) was used for immunisation to produce a high titre polyclonal antiserum. The antiserum to the NP of GBNV at 1:4000 dilution detected successfully natural infection of GBNV and Watermelon bud necrosis virus in a wide range of cucurbitaceous, leguminous and solanaceous hosts from different locations. 相似文献
14.
In this study Spanish and English lay participants were given minimal demographic information regarding 16 hypothetical patients, and were required to rank them in order of priority for a kidney dialysis machine. The patients differed in terms of their gender, smoking behaviour, political affiliation and place of birth. These factors were combined factorially, so that each of the 16 patients presented a unique combination of attributes. The English sample showed a preference for local, female, non-smoking patients. The results for the Spanish sample were similar with respect to place of birth and gender, but smoking behaviour was not significant. Neither sample demonstrated a preference on the basis of political affiliation. The results suggest that certain demographic factors may bias the decision making of individuals or committees involved in the allocation of scarce medical resources. 相似文献
15.
Extraction and genotyping of Cryptosporidium parvum DNA from fecal smears on glass slides stained conventionally for direct microscope examination 下载免费PDF全文
A method was developed for extracting cryptosporidial DNA from stained fecal smears on glass microscope slides. The correct genotype of Cryptosporidium parvum was amplified by PCR from 89 (85%) of 105 smears following conventional staining but not from negative controls. This technique may have applications for analysis of other infectious agents. 相似文献
16.
Palmer SL Gajjar A Reddick WE Glass JO Kun LE Wu S Xiong X Mulhern RK 《Neuropsychology》2003,17(4):548-555
Fifty children diagnosed with medulloblastoma completed 188 psychological evaluations using the Wechsler Intelligence Scales for Children (D. Wechsler, 1974, 1991) over a 7-year study period following 35-40 Gy postoperative craniospinal irradiation. Random coefficient models were used to predict the trend in the children's intellectual performance as a function of time since diagnosis, with both patient and treatment variables as parameters of this function. A quadratic model demonstrated a delay prior to decline in performance for older patients, whereas the younger patients showed an immediate loss of performance with a plateau at approximately 6 years postdiagnosis. A steeper decline was found for those with higher baseline performance. Clinicians may use the proposed predictive model to identify those patients who are at risk of significant intellectual decline. 相似文献
17.
The 2.311 kb EcoRI F fragment of bacteriophage MB78 has been cloned in multicopy vectors pUC19 and pCR90. Salmonella typhimurium strains carrying such plasmids cannot support development of phage MB78 while other Salmonella phages like P22 and 9NA grow normally. Most of the phage MB78 induced functions are normal in such transformed hosts but proper maturation of the phage particles does not take place. Deletion of 138 bp from the 3 end of the cloned fragment reverses the inhibitory effect. Analysis of nucleotide and the deduced amino acid sequence of a 1.2 kb HindIII-SalI fragment of the phage genome which overlaps the 138 bp confirms that this part contains the upstream regulatory region of the major structural protein gene. It seems that in presence of multiple copies of the upstream regulatory region (which includes a number of promoter like sequence) of the coat protein gene, the maturase gene is down regulated and this is effective only in cis, a situation quite similar to that of Q RNA phages. 相似文献
18.
Little is known about patterns of gene expression from cells populating the connective tissues. This study investigated the possible variance of gene expression profile between human osteoblasts (HO) and human fibroblasts (HF) in vitro, using DNA microarray technology. Clustering identification was used to compare expression patterns between HO and HF for biological significance. Our results showed that genes encoding the extracellular matrix or apoptosis-related proteins tended to be expressed in greater abundance in HO, while more proteolysis-related proteins were expressed in higher level in HF. Significant differences in expression were also noted with genes related to signaling pathways. To confirm the array results, three genes (periostin, MFG-E8, MMP-10) were selected and analyzed independently by RT-PCR and northern blot. The results were found consistent with the array data in HO and HF. The present findings suggest that HO and HF differ not only phenotypically but in the expression level of tissue specific genes to assure the turnover and homeostasis of their respective tissues. 相似文献
19.
Neil K. Jairath Alan Dal Pra Randy Vince Robert T. Dess William C. Jackson Jeffrey J. Tosoian Sean M. McBride Shuang G. Zhao Alejandro Berlin Brandon A. Mahal Amar U. Kishan Robert B. Den Stephen J. Freedland Simpa S. Salami Samuel D. Kaffenberger Alan Pollack Phuoc Tran Rohit Mehra Daniel E. Spratt 《European urology》2021,79(3):374-383
ContextMolecular biomarkers aim to address the established limitations of clinicopathologic factors to accurately risk stratify patients with prostate cancer (PCa). Questions remain as to whether sufficient evidence supports adoption of these biomarkers for clinical use.ObjectiveTo perform a systematic review of the available evidence supporting the clinical utility of the Decipher genomic classifier (GC).Evidence acquisitionThe review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by searching PubMed and conference abstracts from January 2010 to June 2020. Evidence was then graded using the criteria of Simon et al (Simon RM, Paik S, Hayes DF. Use of archived specimens in evaluation of prognostic and predictive biomarkers. J Natl Cancer Inst 2009;101:1446–52) and American Urology Association (AUA) criteria.Evidence synthesisIn total, 42 studies and 30 407 patients were included. GC performance data were available for localized, postprostatectomy, nonmetastatic castration-resistant, and metastatic hormone-sensitive PCa as part of retrospective studies (n = 12 141), prospective registries (n = 17 053), and prospective and post hoc randomized trial analyses (n = 1213). In 32 studies (n = 12 600), the GC was independently prognostic for all study endpoints (adverse pathology, biochemical failure, metastasis, and cancer-specific and overall survival) on multivariable analysis and improved the discrimination over standard of care in 24 studies (n = 8543). GC use changed the management in active surveillance (number needed to test [NNT] = 9) and postprostatectomy (NNT = 1.5–4) settings in five studies (n = 4331). Evidence strength was levels 1 and 2 by the Simon criteria for all disease states other than high-risk PCa, and grades A and B by AUA criteria depending on disease state.ConclusionsConsistent data are now present from diverse levels of evidence, which when viewed together, have demonstrated clinical utility of the GC in PCa. The utility of the GC is strongest for intermediate-risk PCa and postprostatectomy decision-making.Patient summaryIn this paper, we review the evidence of the Decipher genomic classification tool for men with prostate cancer. We found consistent evidence that the test helps identify which cancers are more or less aggressive, which in turn aids in personalized treatment decision-making. 相似文献
20.
Jonathan Kentley Rina Allawh Swati Rao Alden Doyle Amar Ahmad Kumar Nadhan Charlotte Proby Catherine A. Harwood Christina L. Chung 《American journal of transplantation》2021,21(3):1215-1226
Organ transplant recipients (OTRs) are at increased risk of cutaneous malignancy. Skin disorders in OTRs of color (OTRoC) have rarely been systematically assessed. We aimed to ascertain the burden of skin disease encountered in OTRoC by prospectively collecting data from OTRs attending 2 posttransplant skin surveillance clinics: 1 in London, UK and 1 in Philadelphia, USA. Retrospective review of all dermatological diagnoses was performed. Data from 1766 OTRs were analyzed: 1024 (58%) white, 376 (21%) black, 261 (15%) Asian, 57 (3%) Middle Eastern/Mediterranean (ME/M), and 48 (2.7%) Hispanic; and 1128 (64%) male. Viral infections affected 45.1% of OTRs, and were more common in white and ME/M patients (P < .001). Fungal infections affected 28.1% and were more common in ME/M patients (P < .001). Inflammatory skin disease affected 24.5%, and was most common in black patients (P < .001). In addition, 26.4% of patients developed skin cancer. There was an increased risk of skin cancer in white vs nonwhite OTRs (HR 4.4, 95% CI 3.5-5.7, P < .001): keratinocyte cancers were more common in white OTRs (P < .001) and Kaposi sarcoma was more common in black OTRs (P < .001). These data support the need for programs that promote targeted dermatology surveillance for all OTRs, regardless of race/ethnicity or country of origin. 相似文献