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PCR Results (pcr + result)
Selected AbstractsAntenatal syphilis serology in pregnant women and follow-up of their infants in northern ItalyCLINICAL MICROBIOLOGY AND INFECTION, Issue 11 2008A. Marangoni Abstract Positive syphilis serology was noted in 119 (0.49%) of the 24 053 pregnant women delivering at St Orsola Hospital in Bologna, Italy, from November 2000 through July 2007. Six presumptive cases of congenital syphilis with IgM western blot positive results were found. Two infants had a positive cerebrospinal fluid (CSF) Venereal Disease Research Laboratory test result (one also had a positive CSF PCR result), another presented long-bone lesions, and the remaining three were preterm. These observations confirmed that antenatal syphilis screening facilitates treatment during pregnancy and offsets vertical transmission; moreover, the use of IgM western blot and careful CSF examination allowed the identification and treatment of high-risk newborns. [source] HLA-B27 typing: Evaluation of an allele-specific PCR melting assay and two flow cytometric antigen assaysCYTOMETRY, Issue 1 2005Michael T. Seipp Abstract Background Human leukocyte antigen B27 (HLA-B27) is a major histocompatibility complex class 1 molecule that is strongly associated with the disease ankylosing spondylitis. Testing for HLA-B27 is of diagnostic value because 90% of patients with ankylosing spondylitis have the B27 antigen. Two commonly used HLA-B27 flow cytometric assays are commercially available. Methods An allele-specific polymerase chain reaction (PCR) melting assay for HLA-B27 was compared with two available antigen assays on 371 clinical samples. The accuracy of the assays was measured by receiver operating characteristic analysis using the PCR method and sequencing as the reference standard. Results When PCR results were compared with those of the antigen assays, complete concordance was observed except for five discrepant results that were resolved by sequence analysis. Using DNA sequencing as the gold standard, the sensitivity and specificity of PCR were 99.6 and 100.0, those of the best single antigen assay were 98.2 and 97.6, and those of a reflex combination of both antigen assays were 98.8 and 97.6. Conclusions The allele-specific PCR melting assay for HLA-B27 genotyping is easy to perform and has better sensitivity and specificity than antigen assays. The performance of the two flow cytometric antigen assays depends on the antibody used and the positive cutoff values assigned. © 2004 Wiley-Liss, Inc. [source] Detection of human papillomavirus DNA in squamous cell carcinoma of the esophagus by auto-nested PCRDISEASES OF THE ESOPHAGUS, Issue 2 2006A. P. Souto Damin SUMMARY., The aim of the present study was to investigate the presence of human papillomavirus (HPV) in surgical specimens of esophageal squamous cell carcinoma. One hundred and sixty-five paraffin-embedded specimens of esophageal carcinoma were analyzed through high-sensitivity auto-nested polymerase chain reaction (PCR) using the consensus GP5+/GP6+ primer. Twenty-six specimens of esophageal mucosa without malignant disease were also studied as a control group. Two different specific primer sets targeting the E6 region of the HPVs 16 and 18 were used for typing. Direct DNA sequence analysis was conducted to confirm positive PCR results. HPV DNA was detected in 26 esophageal carcinomas (15.75%), but in none of the benign esophageal specimens (P < 0.05). Out of the 26 positive cases, 24 were HPV-16 and one was HPV-18. One tumor contained both HPV-16 and -18 DNA. Positive PCR results were confirmed by the amplified viral sequences. Our findings suggest that the presence of either HPV-16 or -18 might be related to development of the malignant phenotype in the esophagus. [source] Diagnosis of tuberculosis: Available technologies, limitations, and possibilitiesJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 5 2003Sanjay K. Garg Abstract Rapid diagnosis and treatment are important for preventing transmission of Mycobacterium tuberculosis. However, the diagnosis of tuberculosis continues to pose serious problems, mainly because of difficulties in differentiating between patients with active tuberculosis and those with healed lesions, normal mycobacterium boris BCG (Bacillus Calmette Guerin) vaccinated individuals, and unvaccinated Manteux positives. Physicians still rely on conventional methods such as Ziehl-Neelsen (ZN) staining, fluorochrome staining, sputum culture, gastric lavage, and other non-traditional methods. Although the tuberculin test has aided in the diagnosis of tuberculosis for more than 85 years, its interpretation is difficult because sensitization with nontuberculous mycobacteria leads to false-positive tests. There have been numerous unsuccessful attempts to develop clinically useful serodiagnostic kits for tuberculosis. A number of proteinaceous and nonprotein antigens (such as acyltrehaloses and phenolglycolipids) have been explored from time to time for the development of such assays but they have not proved to be clinically useful. It has been difficult to develop an ELISA utilizing a suitable antigen because M. tuberculosis shares a large number of antigenic proteins with other microorganisms that may or may not be pathogenic. With the advent of molecular biology techniques, there have been significant advances in nucleic acid-based amplification and hybridization, which are helping to rectify existing flaws in the diagnosis of tuberculosis. The detection of mycobacterial DNA in clinical samples by polymerase chain reaction (PCR) is a promising approach for the rapid diagnosis of tuberculous infection. However, the PCR results must be corrected for the presence of inhibitors as well as for DNA contamination. In the modern era of genetics, marked by proteomics and genomics, the day is not far off when DNA chip-based hybridization assays will instantly reveal mycobacterial infections. J. Clin. Lab. Anal. 17: 155,163, 2003. © 2003 Wiley-Liss, Inc. [source] Genetic polymorphism of CYP2C8 in three Malaysian ethnics: CYP2C8*2 and CYP2C8*3 are found in Malaysian IndiansJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2005Y. D. Muthiah PhD candidate Summary Background:,CYP2C8 is genetically polymorphic. Four variants, CYP2C8*2, CYP2C8*3, CYP2C8*4 and CYP2C8*5, which contain mutations in the coding regions have been reported to exhibit different enzyme activity as compared with CYP2C8*1. Objective:, To determine the allele frequency of three codon-changing variants (CYP2C8*2, CYP2C8*3 and CYP2C8*4) in the Malaysian population. Method:, Healthy unrelated volunteers from three major races in Malaysia were recruited. The study was approved by the local Research Ethics Committee. DNA was extracted using a standard protocol. A two-step multiplex PCR method was developed to detect three alleles of CYP2C8. PCR results were confirmed by subsequent direct DNA sequencing. Result:, Only the Indians showed CYP2C8 polymorphism with allele frequency of 98% for CYP2C8*1, 0·8% for CYP2C8*2 and 1·2% for CYP2C8*3. CYP2C8*4 was not detected in any of the ethnic groups. Conclusion:, To the best of our knowledge, the current study described, for the first time polymorphisms of CYP2C8 in Malaysian Indians. [source] Detection and identification of aquatic mycobacteria in formalin-fixed, paraffin-embedded fish tissuesJOURNAL OF FISH DISEASES, Issue 5 2009F Pourahmad Abstract The isolation of mycobacteria from field samples is problematic, and isolation of the bacterium is sometimes not even attempted. The detection of mycobacteria through traditional histology using formalin-fixed, paraffin-embedded (FFPE) tissues is neither sensitive nor specific. However, detection of mycobacterial DNA from FFPE specimens, suspected of being infected with mammalian mycobacteriosis, is a routine clinical procedure. In the present study, a polymerase chain reaction (PCR)-based method was used to detect and identify mycobacteria in FFPE specimens sampled from fish suspected of being infected with fish mycobacteriosis. A total of 45 fish tissue samples, comprising of 12 tissue samples obtained from experimentally infected fish and the remainder from fish naturally infected with mycobacteria, were analysed using a PCR protocol which amplifies a fragment of the mycobacterial 65 kDa heat-shock protein (hsp65) gene. PCR-restriction enzyme analysis and/or sequencing were employed to further analyse the PCR amplicons. The PCR results were compared with those obtained by histology and culture. Mycobacterial DNA was detected in 34 of the 45 samples examined, of which 16 samples (47%) showed granulomatous reactions on histological examination. Using histology as the gold standard, no false-negative PCR results were obtained. Also, considering the presence or absence of granulomas as a diagnostic criterion, the sensitivity and specificity of PCR in 42 of the FFPE tissues were 16/16 (100%) and 8/26 (,30.8%), respectively. Corresponding microbiological cultures were available for 15 cases, of which 13 were pure Mycobacterium cultures. Of these, 13 were PCR positive (100% sensitivity and 50% specificity). The PCR-based methods used here proved sensitive, specific and rapid for the detection of mycobacteria in routinely processed paraffin wax-embedded and formalin-fixed histological samples, and the results of the study suggest that this method has potential use in retrospective epidemiological studies. [source] Parvovirus B19 infection in pregnancy: Quantitative viral DNA analysis using a kinetic fluorescence detection system (TaqMan PCR)JOURNAL OF MEDICAL VIROLOGY, Issue 2 2002Antje Knöll M.D. Abstract Human parvovirus B19 infections are common in the general population, and infection during pregnancy may cause hydrops fetalis and fetal death. To initiate adequate treatment, accurate laboratory diagnosis is essential. The most sensitive tests are nested PCR systems, but these assays provide semiquantitative results at best. A parvovirus B19 DNA assay was developed based on the real time TaqMan PCR. This method was calibrated on the basis of serial plasmid dilutions and tested with an international parvovirus B19 standard. The assay was capable of quantifying parvovirus B19 DNA from one to about 5,×,107 genome equivalents per reaction (corresponding to 100 to 5,×,109 genome equivalents per ml serum). Samples from 51 pregnant women with suspected acute parvovirus B19 infection were tested, and positive PCR results were obtained in at least one of the materials investigated in 41 cases. The median viral DNA load in maternal blood samples was 1.3,×,104 copies/ml (range 7.2,×,102,2.6,×,107). Maternal virus DNA concentration was not associated with the presence of maternal symptoms and/or fetal complications. As the stage of infection was not known in the majority of cases, our data do not exclude an association between peak levels of parvovirus B19 DNA and the development of complications. Maternal sera and corresponding fetal material were available for concurrent testing from 15 DNA-positive cases: in most fetal samples, viral DNA concentrations were several orders of magnitude higher (up to 2.1,×,1012 copies/ml) compared to the corresponding maternal blood samples. J. Med. Virol. 67:259,266, 2002. © 2002 Wiley-Liss, Inc. [source] The effect of fast reporting by amnio-PCR on anxiety levels in women with positive biochemical screening for Down syndrome , a randomized controlled trialPRENATAL DIAGNOSIS, Issue 3 2002Wing Cheong Leung Abstract Objective To study the effect of fast reporting by polymerase chain reaction on amniotic fluid cells (amnio-PCR) on anxiety levels in women with positive biochemical screening for Down syndrome. Method Between May 2000 and April 2001, 60 screen-positive women were randomized before amniocentesis into either having (group A) or not having (group B) fast-reporting by amnio-PCR. Anxiety levels were measured by the Spielberger State-Trait Anxiety Inventory just prior to amniocentesis, three days (when PCR results were known to group A) and three weeks (when standard karyotype results were known to both groups) afterwards. Results Two women were excluded because in one woman amnio-PCR showed trisomy 21 and the other miscarried shortly after amniocentesis. The state-anxiety scores increased over the three-week period after being informed of the positive-screen result in both groups. The trait- and state-anxiety scores at all points did not differ between the two groups. Conclusions In contrast to the general belief, fast reporting by amnio-PCR did not alleviate anxiety in women who are screen-positive for Down syndrome. Copyright © 2002 John Wiley & Sons, Ltd. 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