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Serum Specimens (serum + specimen)
Selected AbstractsSeroprevalence of Helicobacter pylori Infection Among Schoolchildren and Teachers in TaiwanHELICOBACTER, Issue 3 2007Ding-Bang Lin Abstract Background:,Helicobacter pylori are associated with chronic antral gastritis that is related to duodenal ulcer, gastric ulcer, and probably gastric adenocarcinoma. Infection of H. pylori during childhood is considered an important risk factor for gastric carcinoma in adult life. Materials and Methods:, To examine the epidemiologic characteristics of H. pylori infection among schoolchildren in central Taiwan, a community-based survey was carried out using stratified sampling in 10 elementary schools and three junior high schools including students and theirs teachers. Serum specimens of 1950 healthy schoolchildren (aged 9,15 years old) and 253 teachers who were randomly sampled were screened for the H. pylori antibodies by enzyme-linked immunosorbent assay. Statistical analysis was performed by using the spss for Windows statistical software system. Results:, A total of 332 subjects were H. pylori antibodies positive, giving an overall prevalence of 15.1%. The age-specific seropositive rates were 11.0% in 9,12 years age group, 12.3% in 13,15 years age group, and 45.1% in the teacher group. The older the age, the higher the seroprevalence (OR = 11.53; 95% CI = 6.73,19.74; p < .001 for children vs. teachers). There was no difference in the seroprevalence of H. pylori infection by gender, ethnicity, geographical area, socioeconomic level, parental education, sibship size, family members, and source of drinking water. Conclusion:, The teachers had a much higher prevalence of H. pylori antibodies. The finding suggests that these teachers (adults) might be infected in their early childhood and implies that the poor environmental and hygienic conditions might be responsible for it. It seemed that poor water supply system, sewage disposal, and other environmental hygiene in adult might play some roles in H. pylori infection in Taiwan (before early 1980s). [source] Seroepidemiology of hepatitis A, B, C, and E viruses infection among preschool children in TaiwanJOURNAL OF MEDICAL VIROLOGY, Issue 1 2006Jye-Bin Lin Abstract Taiwan was a hyperendemic area for hepatitis A and B viruses (HAV and HBV) infection before late 1980s. To study the seroprevalence of hepatitis A, B, C, and E viruses (HCV and HEV) infection among preschool children in Taiwan, a community-based survey was carried out in 54 kindergartens in 10 urban areas, 10 rural areas, and 2 aboriginal areas randomly selected through stratified sampling. Serum specimens of 2,538 preschool children were screened for the hepatitis A, C, and E antibodies by a commercially available enzyme immunoassay and for HBV markers by radioimmunoassay methods. The multivariate-adjusted odd ratios (OR) with their 95% confidence intervals (CI) were estimated through the multiple logistic regression analysis. Females had a statistically significantly higher HAV seroprevalence than males. The seroprevalence of HCV infection increased significantly with age. The larger the sibship size, the higher the seroprevalence of HBV infection. Aboriginal children had a significantly higher seroprevalence of HBV and HEV infection and lower seroprevalence of HCV infection than non-aboriginal children. A significantly higher seroprevalence of HBV infection was found in rural children than urban children. There was no significant association between serostatus of HAV and HEV infection and between serostatus of HBV and HCV infection among preschool children in Taiwan. The poor environmental and hygienic conditions in the aboriginal areas might play a role in infection with HBV and HEV. J. Med. Virol. 78:18,23, 2006. © 2005 Wiley-Liss, inc. [source] A Dengue Outbreak among Camp Participants in a Caribbean Island, 1995JOURNAL OF TRAVEL MEDICINE, Issue 2 2000Rob Lyerla Background: Dengue, a mosquito-transmitted viral disease, is a risk for visitors in tropical and subtropical areas. Several participants in a community-assistance program in Tortola, British Virgin Islands, in August, 1995, reported dengue-like symptoms either before or soon after leaving the island. Methods: We conducted a retrospective cohort study to determine the extent of the outbreak, risk factors for illness, and the proportion of inapparent infections. Program participants were interviewed by telephone or mail, and asked to submit a serum sample for dengue diagnosis. A clinically-diagnosed case of dengue was defined as a person with fever and two or more of the following: headache, retro-orbital pain, myalgia, arthralgia, rash, or hemorrhagic manifestations. Serum specimens were tested for virus isolation, polymerase chain reaction (PCR), plaque-reduction neutralization (PRNT) or anti-dengue IgM and IgG antibody. Results: Thirty-two (97%) of the 33 program participants responded; 21 of the 32 (66%) provided at least one serum sample for study. The median age was 17 years; 20 (62%) were women. Of 32 respondents, 22 (69%) met the clinical case definition for dengue: 15 of them (68%) had a positive IgM antibody response and 7 did not submit a serum sample. Dengue 1 virus (DEN-1) was identified by PCR in one case and all 11 positive PRNT results. No asymptomatic infections were identified. No respondent used effective mosquito repellent, and only 2 (6%) used bednets. Conclusion: A DEN-1 outbreak with a high attack rate (69%) occurred in a group of young short-term community aid workers. There were no asymptomatic infections documented. Participants' rare use of bednets or effective mosquito repellent highlights the importance of providing travelers to tropical areas with information about dengue fever and the recommended precautions to protect against infection. [source] Electrochemical Immunoassay for Carbohydrate Antigen-125 Based on Polythionine and Gold Hollow Microspheres Modified Glassy Carbon ElectrodesELECTROANALYSIS, Issue 17 2007Xiao-Hong Fu Abstract A new electrochemical immunosensor for the detection of carbohydrate antigen-125 (CA125), a carcinoma antigen, was developed by immobilization CA125 antibody (anti-CA125) on gold hollow microspheres and porous polythionine (PTH) modified glassy carbon electrodes (GCE). The gold hollow microspheres provided a biocompatible microenvironment for proteins, and greatly amplified the coverage of anti-CA125 molecules on the electrode surface. The performance and factors influencing the immunosensor were investigated in detail. The detection is based on the current change before and after the antigen-antibody interaction. Under optimal conditions, the amperometric changes were proportional to CA125 concentration ranging from 4.5 to 36.5,U/mL with a detection limit of 1.3,U/mL (at 3,). The CA125 immunosensor exhibited good precision, high sensitivity, acceptable stability, accuracy and reproducibility. The as-prepared immunosensors were used to analyze CA125 in human serum specimens. Analytical results suggest that the developed immunoassay has a promising alternative approach for detecting CA125 in the clinical diagnosis. [source] Novel rapid immunochromatographic test based on an enzyme immunoassay for detecting nucleocapsid antigen in SARS-associated coronavirusJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2005Hiroyuki Kogaki Abstract A novel severe acute respiratory syndrome-associated coronavirus (SARS-CoV) has been discovered. The detection of both antigens and antibodies in SARS-CoV from human specimens with suspected SARS plays an important role in preventing infection. We developed a novel rapid immunochromatographic test (RICT) based on the sandwich format enzyme immunoassay (EIA) with an all-in-one device for detecting the native nucleocapsid antigen (N-Ag) of SARS-CoV using monoclonal antibodies (MoAbs), which we produced by immunizing recombinant N-Ag to mice. RICT is a qualitative assay for respiratory aspirates and serum specimens. With this assay, a positive result can be judged subjectively by the appearance of a blue line on the device 15 min after the sample is applied. RICT with several pairs of MoAbs showed a high sensitivity for the detection of recombinant N-Ag as well as viral N-Ag of SARS-CoV. rSN122 and rSN21-2 were the best MoAbs for immobilized antibody and enzyme labeling, respectively. With regard to analytical sensitivity, RICT detected N-Ag at 31 pg/mL for recombinant N-Ag, and at 1.99×102 TCID50/mL for SARS-CoV. The specificity of RICT was 100% when 150 human sera and 50 nasopharyngeal aspirates (NSPs) were used. RICT based on an EIA using the rSN122/rSN21-2 pair is a sensitive, specific, and reliable rapid assay for detecting N-Ag in SARS-CoV treated with either heat or Triton X-100. J. Clin. Lab. Anal. 19:150,159, 2005. © 2005 Wiley-Liss, Inc. [source] Changing Patterns of Drug and Alcohol Use in Fatally Injured Drivers in Washington StateJOURNAL OF FORENSIC SCIENCES, Issue 5 2006Eugene W. Schwilke B.S. ABSTRACT: We have previously reported on patterns of drug and alcohol use in fatally injured drivers in Washington State. Here we revisit that population to examine how drug use patterns have changed in the intervening 9 years. Blood and serum specimens from drivers who died within 4 h of a traffic accident between February 1, 2001, and January 31, 2002, were analyzed for illicit and therapeutic drugs and alcohol. Drugs when present were quantitated. Samples suitable for testing were obtained from 370 fatally injured drivers. Alcohol was detected above 0.01 g/100 mL in 41% of cases. The mean alcohol concentration for those cases was 0.17 g/100 mL (range 0.02,0.39 g/100 mL). Central nervous system (CNS) active drugs were detected in 144 (39%) cases. CNS depressants including carisoprodol, diazepam, hydrocodone, diphenhydramine, amitriptyline, and others were detected in 52 cases (14.1%), cannabinoids were detected in 47 cases (12.7%), CNS stimulants (cocaine and amphetamines) were detected in 36 cases (9.7%), and narcotic analgesics (excluding morphine which is often administered iatrogenically in trauma cases) were detected in 12 cases (3.2%). For those cases which tested positive for alcohol c. 40% had other drugs present which have the potential to cause or contribute to the driver's impairment. Our report also considers the blood drug concentrations in the context of their interpretability with respect to driving impairment. The data reveal that over the past decade, while alcohol use has declined, some drug use, notably methamphetamine, has increased significantly (from 1.89% to 4.86% of fatally injured drivers) between 1992 and 2002. Combined drug and alcohol use is a very significant pattern in this population and is probably overlooked in DUI enforcement programs. [source] Serologic and genotypic analysis of a series of herpes simplex virus type 1 isolates from two patients with genital herpesJOURNAL OF MEDICAL VIROLOGY, Issue 9 2009Kenichi Umene Abstract Herpes simplex virus type 1 (HSV-1) has been reported increasingly as a cause of genital herpes, although HSV-1 is usually associated with oro-labial herpes. In the present study, serum specimens and materials for viral isolation were obtained serially from two patients with recrudescent HSV-1 genital infections to study serology and molecular epidemiology. Recurrent episodes, during which HSV-1 was isolated, were followed by an increase in the level of anti-HSV-1 antibody, suggesting a booster effect from re-exposure to viral antigens and the possible usefulness of the variation in the level of anti-HSV-1 antibody to diagnose recurrence. While genotypes of HSV-1 isolates obtained from one patient were different from those from the other patient, genotypes of sequential HSV-1 isolates obtained from the same patient were the same, implying that the recrudescent genital lesions of the two patients could be attributed to endogenous recurrence of a latent virus. Sera from one patient neutralized HSV-1 isolates obtained from the other patient as well as HSV-1 isolates obtained from the same patient. An HSV-1 isolate obtained during a later episode in one patient was neutralized by sera taken before/during the later episode of the same patient, as effectively as an HSV-1 isolate obtained during an earlier episode in the same patient; thus, in these two cases, HSV-1 was assumed to have multiplied during recurrence despite the presence of an anti-HSV-1 antibody that could neutralize experimentally HSV-1. J. Med. Virol. 81:1605,1612, 2009. © 2009 Wiley-Liss, Inc. [source] Evaluation of hepatitis C antibody testing in saliva specimens collected by two different systems in comparison with HCV antibody and HCV rna in serum,JOURNAL OF MEDICAL VIROLOGY, Issue 1 2001G.J.J. van Doornum Abstract Two different ELISA assays, the Ortho HCV 3.0 ELISA (Ortho Diagnostics Systems) and the Mono-Lisa anti-HCV Plus (Sanofi Diagnostics Pasteur) were evaluated for the detection of hepatitis C virus (HCV) antibody in saliva samples. Specimens were collected from 152 individuals who participated in a longitudinal cohort study on HIV infection, and who used illicit drugs. Saliva specimens were collected using two different systems: Salivette (Sarstedt) and Omni-Sal (Saliva Diagnostic Systems). Saliva specimens were tested following modified protocols by both ELISAs, and the results were compared with serum specimens that were tested according to the instructions of the manufacturer. Serum samples of 102 (67%) participants were positive by both assays, and 50 persons were negative for HCV antibody. A total of 99 of the 102 serum specimens were confirmed as positive using Ortho Riba HCV 3.0 (Ortho Diagnostics System) and Deciscan HCV (Sanofi Diagnostics Pasteur), and 3 yielded discrepant results. As no cut-off level is known for testing saliva samples by ELISA, 3 different levels were chosen: mean (M),+,1 standard deviation (SD), M,+,2 SD, and M,+,3 SD of the optical densities of saliva tests of the 50 HCV serum antibody negative persons. At a level of M,+,1 SD and M,+,2 SD the Salivette/Mono-Lisa combination gave the greatest proportion of HCV antibody positive saliva specimens obtained from the 102 HCV serum antibody positive participants, 88% and 79%, respectively. Differences between the various collection systems and assay combinations were not significant statistically. In 76 of the 102 persons with HCV antibodies in serum, HCV RNA was detected in serum. Salivary presence of HCV RNA, however, could not be demonstrated. The results show that the assays compared are unsuitable for diagnostic use, but the sensitivities of the assays are acceptable for use in epidemiological studies. J. Med. Virol. 64:13,20, 2001. © 2001 Wiley-Liss, Inc. [source] The validity and feasibility of saliva melatonin assessment in the elderlyJOURNAL OF PINEAL RESEARCH, Issue 2 2003Nalaka S. Gooneratne Abstract: Recent work in young and middle-aged subjects suggests that melatonin levels in saliva may represent a viable alternative to serum melatonin measurement. We hypothesized that it may be a valid measure of melatonin levels in older adults as well, but features unique to the elderly may limit its utility. To study this, subjects were admitted to an academic medical center where saliva and serum specimens were collected concurrently in dim light conditions during a 14-hr overnight study period and analyzed for melatonin levels with radioimmunoassays (RIAs). Eighty-five subjects over the age of 65 with a broad range of medical conditions participated in the study. Subjects with dementia, depression and anemia were excluded. We found that saliva volume was inadequate for analysis (<200 ,L) in 23.6% of specimens, with the majority of inadequate volume specimens occurring after midnight and inadequate specimens occurring more frequently in females than in males. The correlation coefficient for saliva melatonin and serum melatonin was r = 0.659 (Spearman, P < 0.001), and r = 0.466 for saliva dim light melatonin onset (DLMO) and serum DLMO. Saliva melatonin levels were 30.9% of serum melatonin levels, with a wide range of ratios noted between subjects. Overall melatonin levels influenced both the correlation and ratio of saliva melatonin to serum melatonin; higher correlations and lower ratios were noted when melatonin levels were high. Saliva specimens provide an economical and practical method for melatonin assessment, however, in older adults, issues such as hyposalivation and low melatonin levels limit the feasibility and validity, respectively, of saliva melatonin. [source] Diagnostic accuracy of a fibrosis serum panel (FIBROSpect II) compared with Knodell and Ishak liver biopsy scores in chronic hepatitis C patientsJOURNAL OF VIRAL HEPATITIS, Issue 10 2006C. Christensen Summary., Liver biopsy is the primary method of assessing liver injury in hepatitis C patients. FIBROSpect II (FS), a diagnostic panel of three extracellular matrix remodelling markers, may be useful as a noninvasive alternative to this procedure. The purpose of this study was to correlate FS results with liver fibrosis scores to determine if this test is sufficiently accurate to be a viable alternative to liver biopsy. A total of 142 serum specimens were evaluated for fibrosis with FS and were compared with Knodell and Ishak fibrosis scores. FS reports an index score ranging from 0.1 to 1.0, which corresponds to the probability of progressive liver fibrosis. Using a FS index cut-off of 0.42, 50 of 54 patients with Ishak 3,6 were classified as having advanced fibrosis (METAVIR F2,F4) and 58 of 88 patients with Ishak 0,2 as having no/mild fibrosis (METAVIR F0,F1), resulting in a sensitivity of 93%, specificity of 66%, and an overall test accuracy of 76%. With a 38% prevalence of advanced fibrosis, the negative predictive value was 94% and positive predictive value was 63%. A biopsy length of ,2 cm was associated with higher concordance between FS results and liver fibrosis scores (P = 0.01). FS was clinically useful in ruling out advanced fibrosis in hepatitis C by identifying patients with mild disease in whom treatment could be deferred. The limitation of this test is its decreased sensitivity and specificity in the middle of the test's reporting range between scores of 0.42 and 0.80. [source] Characterization of hepatitis B surface antigen strains circulating in the Kingdom of CambodiaJOURNAL OF VIRAL HEPATITIS, Issue 1 2006C. T. Srey Summary., A collection of hepatitis B surface antigen (HBsAg)-reactive serum specimens from the Pasteur Institute of Cambodia was investigated for the genotype, predicted serotype and the presence of diagnostically significant mutations in the surface protein. From a set of 794 samples, 15 were identified serologically to harbour possible HBsAg mutants and were investigated further. An additional 20 samples were included into the study for PCR and sequence analysis. Of the 22 samples which were HBV-DNA-positive, 16 were of genotype C with the remaining six being genotype B. Point mutations resulting in amino acid substitutions were noted in 10 samples. The majority of these mutations occurred outside the a determinant. [source] Nonreducing two-dimensional gel electrophoresis for the detection of Bence Jones proteins in serum and urinePROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 1 2004Ingrid Miller Abstract Nonreducing two-dimensional gel electrophoresis (2-DE) is described for the study of immunoglobulin disorders with asynchronous production of single chains. Unlike classical reducing 2-DE, this method can distinguish between complex intact molecules and their free single chains (with different degrees of polymerization) and will thus be helpful for diagnosis of this type of disease. Examples are taken from canine patients, but the method may also be applied to both urine and serum specimens from other species. Nonreducing 2-DE thus represents a useful tool complementary to classical 2-DE, when further information about the appearance of free subunits or modifications of proteins are required, even in the presence of intact molecules. [source] Identifying Combinations of Cancer Markers for Further Study as Triggers of Early InterventionBIOMETRICS, Issue 4 2000Stuart G. Baker Summary. In many long-term clinical trials or cohort studies, investigators repeatedly collect and store tissue or serum specimens and later test specimens from cancer cases and a random sample of controls for potential markers for cancer. An important question is what combination, if any, of the molecular markers should be studied in a future trial as a trigger for early intervention. To answer this question, we summarized the performance of various combinations using Receiver Operating Characteristic (ROC) curves, which plot true versus false positive rates. To construct the ROC curves, we proposed a new class of nonparametric algorithms which extends the ROC paradigm to multiple tests. We fit various combinations of markers to a training sample and evaluated the performance in a test sample using a target region based on a utility function. We applied the methodology to the following markers for prostate cancer, the last value of total prostate-specific antigen (PSA), the last ratio of total to free PSA, the last slope of total PSA, and the last slope of the ratio. In the test sample, the ROC curve for last total PSA was slightly closer to the target region than the ROC curve for a combination of four markers. In a separate validation sample, the ROC curve for last total PSA intersected the target region in 77% of bootstrap replications, indicating some promise for further study. We also discussed sample size calculations. [source] Association between serum levels of soluble tumor necrosis factor receptors/CA 125 and disease progression in patients with epithelial ovarian malignancy,,CANCER, Issue 1 2004A Gynecologic Oncology Group study Abstract BACKGROUND A prospective study was undertaken within the Gynecologic Oncology Group to determine whether serum levels of soluble tumor necrosis factor receptors I (sTNFR-I) and II (sTNFR-II), alone or in combination with CA 125, were associated with clinicopathologic characteristics or outcome in patients with epithelial ovarian malignancies. METHODS Quantitative immunoassays were performed on valid pretreatment serum specimens obtained from patients with epithelial ovarian malignancies to assess levels of sTNFR-I, sTNFR-II, and CA 125. The authors then analyzed the results of these immunoassays for potential correlations with clinicopathologic characteristics and outcome. RESULTS The median age of the 139 women evaluated was 59 years. Seventy-eight percent had Stage III or IV disease, and 58% had serous carcinomas. sTNFR-II was associated with age (P = 0.013), and CA 125 was associated with histologic subtype (P = 0.0009). In addition, sTNFR-I (P = 0.037) and CA 125 (P < 0.0001) were associated with extent of disease. After adjusting for patient age, histologic subtype, and extent of disease, all three biomarkers were predictive of progression-free survival, but not overall survival, when the combination was included in the model. The authors observed a 51% reduction (hazard ratio [HR], 0.49; 95% confidence interval [CI], 0.24,0.99), a 2.9-fold increase (HR, 2.87; 95% CI, 1.15,7.20), and a 22% increase (HR, 1.22; 95% CI, 0.99,1.51) in the risk of progression for each unit increase in the log-transformed levels of sTNFR-I, sTNFR-II, and CA 125, respectively. CONCLUSIONS The observations made in the current study,that among patients with low or high CA 125 levels, those with high sTNFR-I levels and low sTNFR-II levels had the lowest risk, that patients with low-low or high-high sTNFR-I and sTNFR-II levels, respectively, had an intermediate risk, and that patients with low sTNFR-I levels and high sTNFR-II levels had the highest risk of progression,suggested the potential value of simultaneous assessment of all three biomarkers in patients with epithelial ovarian malignancies. Cancer 2004. © 2004 American Cancer Society. [source] | ||||||||||||||||