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
In order to investigate the association of genotypes of HLA-DRB1 and HLA-DQB1 alleles with the genetic susceptibility of chronic urticaria (CU), genotypes of HLA-DRB1 and HLA-DQB1 genes were detected by polymerase cha...In order to investigate the association of genotypes of HLA-DRB1 and HLA-DQB1 alleles with the genetic susceptibility of chronic urticaria (CU), genotypes of HLA-DRB1 and HLA-DQB1 genes were detected by polymerase chain reactions with sequence-specific primers (PCR-SSP) in 42 patients with CU (19 men and 23 women, mean age 30.67±12.45 y old as well as 193 racially matched healthy persons in ethnic Han from Hubei provinece. Gene frequencies of HLA-DRB1*12, *0901 (RR=3.11, χ2=7.579, P=0.006; RR=2.47, χ2=5.684, P=0.017) were significantly increased in CU patients as compared with that in healthy people. Gene frequencies of HLA-DQB1*05 (RR=0.26, χ2=6.683, P=0.01) were significantly decreased in CU patients. It was suggested that CU was found strongly associated with HLA-DRB1*12, *0901 and HLA-DQB1*05, the former might be the genetic markers for susceptibility to CU, but the latter might play a resistive role.展开更多
Objective To evaluate the etiology of Shiga-like toxin-producing Escherichia coli (SLTEC) in children with diarrhea. Methods We designed and synthesized 3 pairs of primers located in the SLT1, SLT2, and eaeA genes of ...Objective To evaluate the etiology of Shiga-like toxin-producing Escherichia coli (SLTEC) in children with diarrhea. Methods We designed and synthesized 3 pairs of primers located in the SLT1, SLT2, and eaeA genes of enterohaemorrhagic Escherichia coli (EHEC), while the virulent genes SLT1, SLT2, and eaeA from E.coli species were amplified by polymerase chain reaction (PCR). Results One strain of EHEC with SLT1, SLT2, and eaeA in 29 reference strains of diarrhea-causing E.coli (DCEC) and 10 strains of other enterobacteria detected by PCR had positive reactions, while all other DCEC and enterobacteria were negative. Of 474 strains of E. coli isolated from 1032 children with diarrhea and detected by PCR, 20 strains of SLT1 producing E. coli (4.2%) positive, and 7 strains of SLT2 producing E.coli (1.5%) positive; while of 74 strains of entero-SLTs-producing and invasive Escherichia coli (ESIEC), 15 strains of SLT1 (20.3%) and 5 strains of SLT2 (6.8%) were positive. Conclusion Shiga-like toxin E. coli has been identified as a major etiologic agent of children with diarrhea in Taiyuan, China.展开更多
AIM To analyze the association of HLA-DRBl with autoimmune hepatitis (AIH) in patients from China.``METHODS In .32 patients and 45 healthy controls,polymerase chain reaction amplification with sequencespecific primers...AIM To analyze the association of HLA-DRBl with autoimmune hepatitis (AIH) in patients from China.``METHODS In .32 patients and 45 healthy controls,polymerase chain reaction amplification with sequencespecific primers (PCR-SSP) was performed to examine the association of certain alleles or polymorphic sequences of HLA-DRB1 with AIH.``RESULTS HLA-DRB1 typing by PCFLSSP showed that DR4had a significantly increased frequency among patients with AIH versus healthy control (46.9% versus 20.8%;relative risk 3.35, P=0.014). In subtypes of DR4, there was a trend of increase in the gene frequency of DRB10405 in patients with AIH versus healthy controls (21.9%vs 6.3%, P=0.04, but Pc 0.08). In addition, asignificant increase was found in the alleles frequency encoding QRRAA from the third hyperpolymorphic region of DR4 in the patients with AIH (86.7% of DR4 positive patients vs 40.0% in DR4 positive controls, P 0.016, Pc =0.028. RR 9.75).``CONCLUSION AIH in Chinese is associated with HLADR4. There is a relationship between QRRAA sequence within the third hyperpolymorphic region of the DRB allele and AIH in Chinese.展开更多
Leptospirosis,a major zoonotic disease widespread in the world,would infect humans and other animals by direct contacting with the soil or water contaminated by the pathogenic leptospires.This report analyzes the accu...Leptospirosis,a major zoonotic disease widespread in the world,would infect humans and other animals by direct contacting with the soil or water contaminated by the pathogenic leptospires.This report analyzes the accuracy of polymerase chain reaction(PCR)assay used in the detection of leptospira specific genes in humans.Seventeen published articles which included 2526 samples satisfied all inclusion standards and were applied to meta-analysis.Pooled sensitivity and specificity were 0.73(95%CI 0.70-0.76)and 0.94(95%CI 0.93-0.95),respectively.Heterogeneity was statistically significant among studies,but none of the sources for heterogeneity(disease stage,PCR type,targeted genes)could adequately interpret this finding.Meta-regression advised that real-time PCR(qPCR)targeted 16 s rRNA would be the best choice for early detection of cases during the acute stage of the disease and was accounted as a good screening tool in all stages of the disease.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.
文摘In order to investigate the association of genotypes of HLA-DRB1 and HLA-DQB1 alleles with the genetic susceptibility of chronic urticaria (CU), genotypes of HLA-DRB1 and HLA-DQB1 genes were detected by polymerase chain reactions with sequence-specific primers (PCR-SSP) in 42 patients with CU (19 men and 23 women, mean age 30.67±12.45 y old as well as 193 racially matched healthy persons in ethnic Han from Hubei provinece. Gene frequencies of HLA-DRB1*12, *0901 (RR=3.11, χ2=7.579, P=0.006; RR=2.47, χ2=5.684, P=0.017) were significantly increased in CU patients as compared with that in healthy people. Gene frequencies of HLA-DQB1*05 (RR=0.26, χ2=6.683, P=0.01) were significantly decreased in CU patients. It was suggested that CU was found strongly associated with HLA-DRB1*12, *0901 and HLA-DQB1*05, the former might be the genetic markers for susceptibility to CU, but the latter might play a resistive role.
文摘Objective To evaluate the etiology of Shiga-like toxin-producing Escherichia coli (SLTEC) in children with diarrhea. Methods We designed and synthesized 3 pairs of primers located in the SLT1, SLT2, and eaeA genes of enterohaemorrhagic Escherichia coli (EHEC), while the virulent genes SLT1, SLT2, and eaeA from E.coli species were amplified by polymerase chain reaction (PCR). Results One strain of EHEC with SLT1, SLT2, and eaeA in 29 reference strains of diarrhea-causing E.coli (DCEC) and 10 strains of other enterobacteria detected by PCR had positive reactions, while all other DCEC and enterobacteria were negative. Of 474 strains of E. coli isolated from 1032 children with diarrhea and detected by PCR, 20 strains of SLT1 producing E. coli (4.2%) positive, and 7 strains of SLT2 producing E.coli (1.5%) positive; while of 74 strains of entero-SLTs-producing and invasive Escherichia coli (ESIEC), 15 strains of SLT1 (20.3%) and 5 strains of SLT2 (6.8%) were positive. Conclusion Shiga-like toxin E. coli has been identified as a major etiologic agent of children with diarrhea in Taiyuan, China.
文摘AIM To analyze the association of HLA-DRBl with autoimmune hepatitis (AIH) in patients from China.``METHODS In .32 patients and 45 healthy controls,polymerase chain reaction amplification with sequencespecific primers (PCR-SSP) was performed to examine the association of certain alleles or polymorphic sequences of HLA-DRB1 with AIH.``RESULTS HLA-DRB1 typing by PCFLSSP showed that DR4had a significantly increased frequency among patients with AIH versus healthy control (46.9% versus 20.8%;relative risk 3.35, P=0.014). In subtypes of DR4, there was a trend of increase in the gene frequency of DRB10405 in patients with AIH versus healthy controls (21.9%vs 6.3%, P=0.04, but Pc 0.08). In addition, asignificant increase was found in the alleles frequency encoding QRRAA from the third hyperpolymorphic region of DR4 in the patients with AIH (86.7% of DR4 positive patients vs 40.0% in DR4 positive controls, P 0.016, Pc =0.028. RR 9.75).``CONCLUSION AIH in Chinese is associated with HLADR4. There is a relationship between QRRAA sequence within the third hyperpolymorphic region of the DRB allele and AIH in Chinese.
基金the National Natural Science Foundation of China(81271781)the Natural Science Foundation of Zhejiang Province(LY17H190002)the Higher Education Institutions of Gansu Province of China(2019B-230)。
文摘Leptospirosis,a major zoonotic disease widespread in the world,would infect humans and other animals by direct contacting with the soil or water contaminated by the pathogenic leptospires.This report analyzes the accuracy of polymerase chain reaction(PCR)assay used in the detection of leptospira specific genes in humans.Seventeen published articles which included 2526 samples satisfied all inclusion standards and were applied to meta-analysis.Pooled sensitivity and specificity were 0.73(95%CI 0.70-0.76)and 0.94(95%CI 0.93-0.95),respectively.Heterogeneity was statistically significant among studies,but none of the sources for heterogeneity(disease stage,PCR type,targeted genes)could adequately interpret this finding.Meta-regression advised that real-time PCR(qPCR)targeted 16 s rRNA would be the best choice for early detection of cases during the acute stage of the disease and was accounted as a good screening tool in all stages of the disease.