Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected...Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.展开更多
Preventive approaches against cancer have not been fully developed and applied.For example,the incidence of some types of cancer,including colon cancer,is highly dependent upon lifestyle,and therefore,amenable to prev...Preventive approaches against cancer have not been fully developed and applied.For example,the incidence of some types of cancer,including colon cancer,is highly dependent upon lifestyle,and therefore,amenable to prevention.Among the lifestyle factors,diet strongly affects the incidence of colon cancer; however,there are no definitive dietary recommendations that protect against this malignancy.The association between diet-derived bioactives and development of colonic neoplasms will remain ill defined if we do not take into account:(1) the identity of the metabolites present in the colonic lumen;(2) their concentrations in the colon; and(3) the effect of the colonic contents on the function of individual bioactives.We review two approaches that address these questions:the use of fecal water and in vitro models of the human colon.Compared to treatment with individual diet-derived compounds,the exposure of colon cancer cells to samples from fecal water or human colon simulators mimics closer the in vitro conditions and allows for more reliable studies on the effects of diet on colon cancer development.The rationale and the advantages of these strategies are discussed from the perspective of a specific question on how to analyze the combined effect of two types of bioactives,butyrate and polyphenol metabolites,on colon cancer cells.展开更多
基金supported by a research grant from the Office of the Vice-Chancellor for Research and Development,University of the Philippines-Diliman(Grant No.101007 PNSE)to W.L.R.and H.J.S
文摘Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.
基金Supported by NIH grants Acknowledges the Support of the European Science Foundation,in the framework of the Research Networking Program,No.R15CA152852-01The European Network for Gastrointestinal Health Research,No.R15CA149589-01
文摘Preventive approaches against cancer have not been fully developed and applied.For example,the incidence of some types of cancer,including colon cancer,is highly dependent upon lifestyle,and therefore,amenable to prevention.Among the lifestyle factors,diet strongly affects the incidence of colon cancer; however,there are no definitive dietary recommendations that protect against this malignancy.The association between diet-derived bioactives and development of colonic neoplasms will remain ill defined if we do not take into account:(1) the identity of the metabolites present in the colonic lumen;(2) their concentrations in the colon; and(3) the effect of the colonic contents on the function of individual bioactives.We review two approaches that address these questions:the use of fecal water and in vitro models of the human colon.Compared to treatment with individual diet-derived compounds,the exposure of colon cancer cells to samples from fecal water or human colon simulators mimics closer the in vitro conditions and allows for more reliable studies on the effects of diet on colon cancer development.The rationale and the advantages of these strategies are discussed from the perspective of a specific question on how to analyze the combined effect of two types of bioactives,butyrate and polyphenol metabolites,on colon cancer cells.
