Perera D.,University Malaysia Sarawak |
Shimizu H.,Japan National Institute of Infectious Diseases |
Yoshida H.,Japan National Institute of Infectious Diseases |
Van Tu P.,Pasteur Institute of Ho Chi Minh City |
And 3 more authors.
Journal of Medical Virology
The VP4, VP2, and VP1 gene regions were evaluated for their usefulness in typing human enteroviruses. Three published RT-PCR primers sets targeting separately these three gene regions were used. Initially, from a total of 86 field isolates (36 HEV-A, 40 HEV-B, and 10 HEV-C) tested, 100% concordance in HEV-A was identi-fied from all three gene regions (VP4, VP2, and VP1). However, for HEV-B and HEV-C viruses, only the VP2 and VP1 regions, and not VP4, showed 100% concordance in typing these viruses. To evaluate further the usefulness of VP4 in typing HEV-A enteroviruses, 55 Japanese and 203 published paired VP4 and VP1 nucleotide sequences were also examined. In each case, typing by VP4 was 100% in concordance with typing using VP1. Given these results, it is proposed that for HEV-A enteroviruses, all three gene regions (VP4, VP2, and VP1), would be useful for typing these viruses. These options would enhance the capability of laboratories in identifying these viruses and would greatly help in outbreaks of hand, foot, and mouth disease. © 2010 Wiley-Liss, Inc. Source
Huy N.T.,Nagasaki University |
Hamada M.,Cairo University |
Kikuchi M.,Nagasaki University |
Lan N.T.P.,Pasteur Institute of Ho Chi Minh City |
And 3 more authors.
Several human genetic variants, HLA antigens and alleles are reportedly linked to post-schistosomal hepatic disorder (PSHD), but the results from these reports are highly inconclusive. In order to estimate overall associations between human genetic variants, HLA antigens, HLA alleles and PSHD, we systematically reviewed and performed a meta-analysis of relevant studies in both post-schistosomal hepatic disorder and post-schistosomal non-hepatic disorder patients. PubMed, Scopus, Google Scholar, The HuGE Published Literature database, Cochrane Library, and manual search of reference lists of articles published before July 2009 were used to retrieve relevant studies. Two reviewers independently selected articles and extracted data on study characteristics and data regarding the association between genetic variants, HLA antigens, HLA alleles and PSHD in the form of 2 × 2 tables. A meta-analysis using fixed-effects or random-effects models to pooled odds ratios (OR) with corresponding 95% confidence intervals were calculated only if more than one study had investigated particular variation. We found 17 articles that met our eligibility criteria. Schistosoma mansoni and Schistosoma japonicum were reported as the species causing PSHD. Since human genetic variants were only investigated in one study, these markers were not assessed by meta-analysis. Thus, only HLA-genes (a total of 66 HLA markers) were conducted in the meta-analysis. Our meta-analysis showed that human leucocyte antigens HLA-DQB1*0201 (OR = 2.64, P= 0.018), DQB1*0303 (OR = 1.93, P= 0.008), and DRB1*0901 (OR = 2.14, P= 0.002) alleles and HLA-A1 (OR = 5.10, P= 0.001), A2 (OR = 2.17, P= 0.005), B5 (OR = 4.63, P= 0.001), B8 (OR = 2.99, P= 0.02), and B12 (OR = 5.49, P= 0.005) serotypes enhanced susceptibility to PSHD, whereas HLA-DQA1*0501 (OR = 0.29, P≤ 0.001) and DQB1*0301 (OR = 0.58, P= 0.007) were protective factors against the disease. We further suggested that the DRB1*0901-DQB1*0201, DRB1*0901-DQB1*0303 and A1-B8 haplotypes enhanced susceptibility to PSHD, whereas DQA1*0501-DQB1*0301 linkage decreased the risk of PSHD. The result improved our understanding of the association between the HLA loci and PSHD with regard to pathogenic or protective T-cells and provided novel evidence that HLA alleles may influence disease severity. © 2011 Elsevier Ireland Ltd. Source
Dinh T.Q.,Vietnam National University, Ho Chi Minh City |
Le H.V.,Ho Chi Minh City University of Technology |
Cao T.H.,Vietnam National University, Ho Chi Minh City |
Luong Q.C.,Pasteur Institute of Ho Chi Minh City |
Diep H.T.,Pasteur Institute of Ho Chi Minh City
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
With recent rises of sophisticated and dangerous epidemics, there is a growing need for a system that could predict disease severity with high accuracy. In this paper, we address the problem of forecasting the magnitude of dengue in a short term period, i.e. one week ahead. We consider inputs as both statistics of historical cases and biological factors affecting the dengue virus, including the temperature, population and mosquito density. We propose a two-phase model simulating the disease transmission process, which are the local outbreak and then province transmission. The locality phase estimates the number of potential cases in each province independently in the following week. Then, in the transmission phase, an artificial neural network is used to predict the mobility of the dengue virus across provinces. Our proposed method obtains a higher accuracy than the conventional models of time series, linear regression, and ARIMA. Moreover, this provides the first research results about dengue prediction in Vietnam. © Springer-Verlag Berlin Heidelberg 2016. Source
Taneja N.,Jawaharlal Institute of Postgraduate Medical Education & Research |
Nato F.,Institute Pasteur Paris |
Dartevelle S.,Institute Pasteur Paris |
Sire J.M.,Institute Pasteur Of Dakar |
And 12 more authors.
Background: We describe a test for rapid detection of S. dysenteriae 1 in bacterial cultures and in stools, at the bedside of patients. Methodology/Principal Findings: The test is based on the detection of S. dysenteriae 1 lipopolysaccharide (LPS) using serotype 1-specific monoclonal antibodies coupled to gold particles and displayed on a one-step immunochromatographic dipstick. A concentration as low as 15 ng/ml of LPS was detected in distilled water and in reconstituted stools in 10 minutes. In distilled water and in reconstituted stools, an unequivocal positive reaction was obtained with 1.6×106 CFU/ml and 4.9×106 CFU/ml of S. dysenteriae 1, respectively. Optimal conditions to read the test have been determined to limit the risk of ambiguous results due to appearance of a faint yellow test band in some negative samples. The specificity was 100% when tested with a battery of Shigella and unrelated strains in culture. When tested on 328 clinical samples in India, Vietnam, Senegal and France by laboratory technicians and in Democratic Republic of Congo by a field technician, the specificity (312/316) was 98.7% (95% CI:96.6-99.6%) and the sensitivity (11/12) was 91.7% (95% CI:59.8-99.6%). Stool cultures and the immunochromatographic test showed concordant results in 98.4 % of cases (323/328) in comparative studies. Positive and negative predictive values were 73.3% (95% CI:44.8-91.1%) and 99.7% (95% CI:98-100%). Conclusion: The initial findings presented here for a simple dipstick-based test to diagnose S. dysenteriae 1 demonstrates its promising potential to become a powerful tool for case management and epidemiological surveys. © 2011 Taneja et al. Source
Duran C.,University of Chile |
Nato F.,Institute Pasteur Paris |
Dartevelle S.,Institute Pasteur Paris |
Phuong L.N.T.,Pasteur Institute of Ho Chi Minh City |
And 15 more authors.
Background: We evaluated a dipstick test for rapid detection of Shigella sonnei on bacterial colonies, directly on stools and from rectal swabs because in actual field situations, most pathologic specimens for diagnosis correspond to stool samples or rectal swabs. Methodology/Principal Findings: The test is based on the detection of S. sonnei lipopolysaccharide (LPS) O-side chains using phase I-specific monoclonal antibodies coupled to gold particles, and displayed on a one-step immunochromatographic dipstick. A concentration as low as 5 ng/ml of LPS was detected in distilled water and in reconstituted stools in 6 minutes. This is the optimal time for lecture to avoid errors of interpretation. In distilled water and in reconstituted stools, an unequivocal positive reaction was obtained with 4 × 106 CFU/ml of S. sonnei. The specificity was 100% when tested with a battery of Shigella and different unrelated strains. When tested on 342 rectal swabs in Chile, specificity (281/295) was 95.3% (95% CI: 92.9% - 97.7%) and sensitivity (47/47) was 100%. Stool cultures and the immunochromatographic test showed concordant results in 95.5% of cases (328/342) in comparative studies. Positive and negative predictive values were 77% (95% CI: 65% - 86.5%) and 100% respectively. When tested on 219 stools in Chile, Vietnam, India and France, specificity (190/198) was 96% (95% CI 92%-98%) and sensitivity (21/21) was 100%. Stool cultures and the immunochromatographic test showed concordant results in 96.3% of cases (211/219) in comparative studies. Positive and negative predictive values were 72.4% (95% CI 56.1%-88.6%) and 100%, respectively. Conclusion: This one-step dipstick test performed well for diagnosis of S. sonnei both on stools and on rectal swabs. These data confirm a preliminary study done in Chile. © 2013 Duran et al. Source