46 results on '"Van Tong H"'
Search Results
2. Natural and recombinant equine chorionic gonadotropins past and future in animal reproductive technology
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Tien Thach Duong, Khac Cuong Bui, Van Tong Hoang, Van Chi Vo, Kim Khue Ngo, Thi Phuong Hien Nguyen, Van Hai Nong, Yves Combarnous, and Thi Mong Diep Nguyen
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Veterinary medicine ,SF600-1100 - Abstract
Equine Chorionic Gonadotropin (eCG) previously named Pregnant Mare Serum Gonadotropin (PMSG) has been widely used since the 40s in animal reproduction control. It is extracted from the blood of pregnant mares between days 40 and 120 of gestation. Animal welfare organizations have voiced concerns against mares bleeding conditions. There is currently no effective substitute for the natural PMSG. In this review, we summarize the basic knowledge of the structure and biology of eCG, and the research on recombinant eCG production in the past five years.
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- 2022
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3. Functional Variants and Aberrant Methylation in the SOCS3 Promoter Region Influence the Progression of HBV-Related Liver Diseases
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Hoan, N.X., primary, Van Tong, H., additional, Giang, D.P., additional, Toan, N.L., additional, Song, L.H., additional, Bock, C.-T., additional, Kremsner, P.G., additional, and Velavan, T.P., additional
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- 2016
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4. FRI-245 - Functional Variants and Aberrant Methylation in the SOCS3 Promoter Region Influence the Progression of HBV-Related Liver Diseases
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Hoan, N.X., Van Tong, H., Giang, D.P., Toan, N.L., Song, L.H., Bock, C.-T., Kremsner, P.G., and Velavan, T.P.
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- 2016
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5. Ficolin-2 Levels and FCN2 Genetic Polymorphisms as a Susceptibility Factor in Schistosomiasis
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Ouf, E. A., primary, Ojurongbe, O., additional, Akindele, A. A., additional, Sina-Agbaje, O. R., additional, Van Tong, H., additional, Adeyeba, A. O., additional, Kremsner, P. G., additional, Kun, J. F. J., additional, and Velavan, T., additional
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- 2012
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6. Establishment of an in-house one-step real-time RT-PCR assay for detection of Zaire ebolavirus
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Xuan Su Hoang, Thi Thu Hang Dinh, Van Tong Hoang, Huu Tho Ho, Tien Sy Bui, Van An Nguyen, and Thai Son Nguyen
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ebola virus ,real-time RT-PCR ,Vietnam ,Zaire ebolavirus ,Science - Abstract
Ebola virus is a deadly causative agent with a high mortality rate of up to 90%, therefore it has been classified by the Center for Disease Control and Prevention (CDC) as a category A biological agent. The World Health Organization (WHO) recommended using RT-PCR based assays to rapidly detect the virus. In the present study, we established an in-house assay for detection of Zaire ebolavirus via real-time RT-PCR. The nucleotide sequence of the Zaire ebolavirus nucleoprotein (NP) gene was retrieved from the Genbank for designing primer pairs and probes using Primer Express 3.0 software. The RNA positive control was generated by in vitro RNA transcript synthesis. The optimal components in the 20 μl final volume of the real-time RT-PCR assay were 10 μl 2X QuantiTect Probe RT-PCR master mix, 0,6 μM of each primer, 0,1 μM of the probe, 0,2 μl RT mix and 5 μl of RNA template. The thermal cycle conditions were as follows: 50°C for 30 min, 95°C for 15 min, then 45 cycles of 15 s at 94°C, 60s at 60°C. The limit of detection of the assay was 100 copies/reaction and 1414 FFU/ml with the positive RNA panel and sample panel of RNA extracted from cell culture supernatants of cells infected with Zaire ebolavirus 2014/Gueckedou-C05, respectively. The specificity of this assay was 100% when tested with the positive RNA panel of Ebola virus and other haemorrhagic fever viruses. In conclusion, we successfully established an in-house real-time RT-PCR assay for detection of Zaire ebolavirus in Vietnam with a limit of detection of 1414 FFU/ml and specificity of 100%.
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- 2017
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7. Reliable and rapid characterization of functional FCN2 gene variants reveals diverse geographical patterns
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Ojurongbe Olusola, Ouf Eman, Van Tong Hoang, Toan Nguyen L, Song Le H, Luz Paola R, Messias-Reason Iara JT, Nurjadi Dennis, Zanger Philipp, Kun Jürgen FJ, Kremsner Peter G, and Velavan Thirumalaisamy P
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FRET ,Ficolin-2 ,Genotypes ,Haplotypes ,Distribution ,Internal medicine ,RC31-1245 ,Genetics ,QH426-470 - Abstract
Abstract Background Ficolin-2 coded by FCN2 gene is a soluble serum protein and an innate immune recognition element of the complement system. FCN2 gene polymorphisms reveal distinct geographical patterns and are documented to alter serum ficolin levels and modulate disease susceptibility. Methods We employed a real-time PCR based on Fluorescence Resonance Energy Transfer (FRET) method to genotype four functional SNPs including -986 G > A (#rs3124952), -602 G > A (#rs3124953), -4A > G (#rs17514136) and +6424 G > T (#rs7851696) in the ficolin-2 (FCN2) gene. We characterized the FCN2 variants in individuals representing Brazilian (n = 176), Nigerian (n = 180), Vietnamese (n = 172) and European Caucasian ethnicity (n = 165). Results We observed that the genotype distribution of three functional SNP variants (−986 G > A, -602 G > A and -4A > G) differ significantly between the populations investigated (p p Conclusions The observed distribution of the FCN2 functional SNP variants may likely contribute to altered serum ficolin levels and this may depend on the different disease settings in world populations. To conclude, the use of FRET based real-time PCR especially for FCN2 gene will benefit a larger scientific community who extensively depend on rapid, reliable method for FCN2 genotyping.
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- 2012
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8. Association of UGT1A1 gene variants, expression levels, and enzyme concentrations with 2,3,7,8-TCDD exposure in individuals exposed to Agent Orange/Dioxin.
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Van Quang H, Vuong NB, Trang BNL, Toan NL, and Van Tong H
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- Humans, Agent Orange, 2,4-Dichlorophenoxyacetic Acid, 2,4,5-Trichlorophenoxyacetic Acid analysis, Polymorphism, Single Nucleotide, RNA, Messenger genetics, Polychlorinated Dibenzodioxins toxicity, Dioxins
- Abstract
Among the congener of dioxin, 2,3,7,8-TCDD is the most toxic, having a serious long-term impact on the environment and human health. UDP-glucuronosyltransferase 1A1 (UGT1A1) plays a crucial role in the detoxification and excretion of endogenous and exogenous lipophilic compounds, primarily in the liver and gastrointestinal tract. This study aimed to investigate the association of UGT1A1 gene polymorphisms, expression levels, and enzyme concentration with Agent Orange/Dioxin exposure. The study included 100 individuals exposed to Agent Orange/Dioxin nearby Da Nang and Bien Hoa airports in Vietnam and 100 healthy controls. UGT1A1 SNP rs10929303, rs1042640 and rs8330 were determined by Sanger sequencing, mRNA expression was quantified by RT-qPCR and plasma UGT1A1 concentrations were measured by ELISA. The results showed that UGT1A1 polymorphisms at SNPs rs10929303, rs1042640 and rs8330 were associated with Agent Orange/Dioxin exposure (OR = 0.55, P = 0.018; OR = 0.55, P = 0.018 and OR = 0.57, P = 0.026, respectively). UGT1A1 mRNA expression levels and enzyme concentration were significantly elevated in individuals exposed to Agent Orange/Dioxin compared to controls (P < 0.0001). Benchmark dose (BMD) analyses showed that chronic exposure to 2,3,7,8-TCDD contamination affects the UGT1A1 mRNA and protein levels. Furthermore, UGT1A1 polymorphisms affected gene expression and enzyme concentrations in individuals exposed to Agent Orange/Dioxin. In conclusion, UGT1A1 gene polymorphisms, UGT1A gene expression levels and UGT1A1 enzyme concentrations were associated with Agent Orange/Dioxin exposure. The metabolism of 2,3,7,8-TCDD may influence UGT1A gene expression and enzyme concentrations., (© 2024. The Author(s).)
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- 2024
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9. Clinical association and diagnostic significance of miRNA-29a and miRNA-147b in type 2 diabetes mellitus.
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Dzung PT, Trung NT, Van Khanh L, Chinh DD, Van De D, Van Tong H, and Toan NL
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- Humans, Biomarkers, MicroRNAs genetics, Diabetes Mellitus, Type 2 diagnosis, Diabetes Mellitus, Type 2 genetics
- Abstract
Background: Micro RNAs (miRs) expression is involved in the pathogenesis of type 2 diabetes mellitus (T2DM). This study investigates the expression levels of plasma miR-29a, miR-146a, and miR-147b and their correlations with clinical parameters in patients with T2DM. Methods: 105 patients with T2DM who categorized either as newly diagnosed T2DM (n=52) or treated T2DM (n=53) and 93 healthy individuals were included in this study. The expression levels of miR-29a, miR-146a, and miR-147b were quantified by real-time PCR and analyzed for possible association with T2DM. Results: The expressions of miR-29a and miR-147b were significantly increased in T2DM patients compared with healthy controls ( P <0.0001). The expression levels of miR-29a in newly diagnosed T2DM patients were higher than that in the group of treated T2DM ( P =0.002). The expression of studied miRs was correlated with several clinical parameters such as blood glucose levels, HbA1C, microalbuminuria, C-peptide, triglyceride levels as well as the HOMA-β index. The expression levels of miR-29a and miR-147b show a potential diagnostic performance to discriminate newly diagnostic T2DM (AUCs=0.77 and 0.84, respectively) and beta-cell dysfunction (AUCs= 0.62 and 0.75, respectively). Conclusions: The plasma miR-29a and miR-147b expression levels in T2DM patients are significantly associated with T2DM while miR-146a shows poor evidence in relation to T2DM. miR-147b shows potential as a biomarker for the diagnosis of T2DM and pancreatic beta cell dysfunction., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
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- 2023
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10. Custom gene expression panel for evaluation of potential molecular markers in hepatocellular carcinoma.
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Pallerla SR, Hoan NX, Rachakonda S, Meyer CG, Van Tong H, Toan NL, Linh LTK, Giang DP, Kremsner PG, Bang MH, Song LH, and Velavan TP
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- Humans, alpha-Fetoproteins, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Prognosis, Gene Expression, Gene Expression Regulation, Neoplastic, Glypicans genetics, Glypicans metabolism, Carcinoma, Hepatocellular pathology, Liver Neoplasms pathology
- Abstract
Background: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. It is a highly heterogeneous disease with poor prognosis and limited treatment options, which highlights the need for reliable biomarkers. This study aims to explore molecular markers that allow stratification of HCC and may lead to better prognosis and treatment prediction., Materials and Methods: We studied 20 candidate genes (HCC hub genes, potential drug target genes, predominant somatic mutant genes) retrieved from literature and public databases with potential to be used as the molecular markers. We analysed expression of the genes by RT-qPCR in 30 HCC tumour and adjacent non-tumour paired samples from Vietnamese patients. Fold changes in expression were then determined using the 2
-∆∆CT method, and unsupervised hierarchical clustering was generated using Cluster v3.0 software., Results: Clustering of expression data revealed two subtypes of tumours (proliferative and normal-like) and four clusters for genes. The expression profiles of the genes TOP2A, CDK1, BIRC5, GPC3, IGF2, and AFP were strongly correlated. Proliferative tumours were characterized by high expression of the c-MET, ARID1A, CTNNB1, RAF1, LGR5, and GLUL1 genes. TOP2A, CDK1, and BIRC5 HCC hub genes were highly expressed (> twofold) in 90% (27/30), 83% (25/30), and 83% (24/30) in the tissue samples, respectively. Among the drug target genes, high expression was observed in the GPC3, IGF2 and c-MET genes in 77% (23/30), 63% (19/30), and 37% (11/30), respectively. The somatic mutant Wnt/ß-catenin genes (CTNNB1, GLUL and LGR5) and TERT were highly expressed in 40% and 33% of HCCs, respectively. Among the HCC marker genes, a higher percentage of tumours showed GPC3 expression compared to AFP expression [73% (23/30) vs. 43% (13/30)]., Conclusion: The custom panel and molecular markers from this study may be useful for diagnosis, prognosis, biomarker-guided clinical trial design, and prediction of treatment outcomes., (© 2022. The Author(s).)- Published
- 2022
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11. SWEET Gene Family in Sugar Beet ( Beta vulgaris ): Genome-Wide Survey, Phylogeny and Expression Analysis.
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Viet La H, Duc Chu H, Thi Ha Q, Huyen Tran TT, Van Tong H, Van Tran T, Ngoc Le QT, Thu Bui HT, and Bang Cao P
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- Genes, Plant, Genome, Plant, Phylogeny, Plants, Sugars, Vegetables genetics, Beta vulgaris genetics
- Abstract
<b>Background and Objective:</b> The SWEET (Sugars Will Eventually be Exported Transporter) proteins play important roles in modulating the growth and development processes in plants. However, little information is available on the SWEET family in sugar beet (<i>Beta vulgaris</i>). The objectives of this present study were to genome-wide identify and characterize the BvSWEET family in sugar beet. <b>Materials and Methods:</b> Based on the available genome, proteome and transcriptome databases of sugar beet, various computational tools have been used to analyze the nucleotide and full-length protein sequences of members of the BvSWEET family. <b>Results:</b> A total of 16 members of the BvSWEET family has been identified in sugar beet at the genome-wide scale. Structural analysis indicated that the BvSWEET family exhibited variable characteristics. Furthermore, the BvSWEET family in sugar beet could be categorized into four distinct groups like in other plant species. Of our interest, we found that some <i>BvSWEET</i> genes exhibited strongly preferential expression in major organs/tissues under adverse environmental stimuli. <b>Conclusion:</b> The results provided a comprehensive foundation for further functional characterization of the <i>BvSWEET </i>gene family.
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- 2022
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12. Antimicrobial resistance in colonizing group B Streptococcus among pregnant women from a hospital in Vietnam.
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Van Du V, Dung PT, Toan NL, Van Mao C, Bac NT, Van Tong H, Son HA, Thuan ND, and Viet NT
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- Adult, Anti-Bacterial Agents pharmacology, Female, Humans, Middle Aged, Pregnancy, Pregnancy Complications, Infectious epidemiology, Pregnancy Complications, Infectious microbiology, Streptococcal Infections epidemiology, Streptococcal Infections microbiology, Vietnam epidemiology, Young Adult, Anti-Bacterial Agents therapeutic use, Drug Resistance, Bacterial, Pregnancy Complications, Infectious drug therapy, Streptococcal Infections drug therapy, Streptococcus agalactiae drug effects
- Abstract
Few studies have been conducted on group B Streptococcus (GBS) in Vietnam. We determined the GBS colonization and antimicrobial resistance vaginal-rectal profile of 3863 Vietnamese pregnant women over 5 years. Maternal GBS colonization was characterized by antibiotic susceptibility. Overall, the GBS colonization rate was 8.02% (95% CI: 7.20-8.94%). Compared to sampling ≥ 35 weeks of gestation, the GBS colonization rate was statistically higher (p = 0.004) with sampling < 35 weeks. Among 272 antimicrobial susceptibility testing isolates, all were susceptible to ampicillin, penicillin, ceftriaxone, cefotaxime, vancomycin, and quinupristin/dalfopristin. Resistance was highest for tetracycline (89.66%), followed by erythromycin (76.23%) and clindamycin (58.21%). Multidrug resistance and resistance to ≥ 6 different antibiotics were 60.66% and 8.82%, respectively. Resistance to clindamycin but not erythromycin (L phenotype) was 2.2%. The clindamycin resistance rate was significantly increased (p = 0.005) during the study period. These data demonstrate a low rate of maternal GBS colonization. The high rate of erythromycin, clindamycin, and multidrug resistance to GBS that can be transmitted to neonates is an important risk factor to consider. β-lactams continue to be appropriate for first-line treatment and prophylaxis in the study area. Ongoing monitoring should be considered in the future., (© 2021. The Author(s).)
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- 2021
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13. Impact of VSIG4 gene polymorphisms on susceptibility and functional status of rheumatoid arthritis.
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Antunes Andrade F, Goeldner Eibofner I, Pieczarka C, van Tong H, Sena L, Skare T, Ramos da Rosa Utiyama S, Jose de Messias-Reason I, and P Velavan T
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- Adolescent, Adult, Aged, Alleles, Arthritis, Rheumatoid epidemiology, Arthritis, Rheumatoid pathology, Brazil epidemiology, Humans, Middle Aged, Polymorphism, Single Nucleotide genetics, Young Adult, Arthritis, Rheumatoid genetics, Genetic Association Studies, Genetic Predisposition to Disease, Receptors, Complement genetics
- Abstract
The complement receptor of the immunoglobulin superfamily (CRIg, encoded by the VSIG4 gene) is a macrophage receptor involved in the clearance of immune complexes and autologous cells. Our results suggest that the VSIG4 rs1044165T allele is a risk factor for severe functional status of rheumatoid arthritis in women, possibly by affecting VSIG4 gene expression., (© 2021 John Wiley & Sons Ltd.)
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- 2021
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14. Maternal Vaginal Colonization and Extended-Spectrum Beta-Lactamase-Producing Bacteria in Vietnamese Pregnant Women.
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Viet NT, Van Du V, Thuan ND, Van Tong H, Toan NL, Van Mao C, Van Tuan N, Pallerla SR, Nurjadi D, Velavan TP, and Son HA
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Extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) resistance to commonly prescribed drugs is increasing in Vietnam. During pregnancy, ESBL-E may predispose women to reproductive tract infections and increases the risk for neonatal morbidity. Vaginal colonization and infections by Escherichia coli and Klebsiella pneumoniae are seldom studied in Vietnam. In this study, we investigated ESBL-producing Enterobacterales in the birth canal of pregnant women. Between 2016 and 2020, vaginal swabs were collected from 3104 pregnant women (mean gestational age of 31 weeks) and inoculated onto MacConkey agar plates. Colonies were subjected to direct identification and antimicrobial susceptibility testing using the VITEK
® -2 automated compact system and disk diffusion. ESBL production was determined phenotypically. E. coli , Klebsiella species were identified in 30% (918/3104) of the vaginal swabs, with E. coli being the most common (73%; 667/918). ESBL-production was detected in 47% (432/918) of Enterobacterales, with frequent multidrug-resistant phenotype. The overall prevalence of carbapenem resistance was low (8%). Over 20% of Klebsiella spp. were carbapenem-resistant. Pregnant women had a high prevalence of colonization and may transmit ESBL-E to neonates at birth, an important risk factor to be considered. The high rate of ESBL-producers and carbapenem resistance in Enterobacterales in Vietnam emphasizes the need for consequent surveillance and access to molecular typing.- Published
- 2021
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15. Molecular surveillance and temporal monitoring of malaria parasites in focal Vietnamese provinces.
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Van Long B, Allen G, Brauny M, Linh LTK, Pallerla SR, Huyen TTT, Van Tong H, Toan NL, Quyet D, Son HA, and Velavan TP
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- Coinfection parasitology, Genotype, Malaria, Falciparum parasitology, Malaria, Vivax parasitology, Vietnam, Antigens, Protozoan genetics, Genetic Variation, Malaria parasitology, Merozoite Surface Protein 1 genetics, Plasmodium falciparum genetics, Plasmodium malariae genetics, Plasmodium vivax genetics, Protozoan Proteins genetics
- Abstract
Background: While the World Health Organization (WHO) Southeast Asia region has the second highest incidence of malaria worldwide, malaria in Vietnam is focal to few provinces, where delayed parasite clearance to anti-malarial drugs is documented. This study aims to understand Plasmodium species distribution and the genetic diversity of msp1 and msp2 of parasite populations using molecular tools., Methods: A total of 222 clinical isolates from individuals with uncomplicated malaria were subjected to Plasmodium species identification by nested real-time PCR. 166 isolates positive for Plasmodium falciparum mono infections were further genotyped for msp1 (MAD20, K1, and RO33), and msp2 allelic families (3D7 and FC27). Amplicons were resolved through capillary electrophoresis in the QIAxcel Advanced system., Results: Mono-infections were high and with 75% P. falciparum, 14% Plasmodium vivax and 9% P. falciparum/P. vivax co-infections, with less than 1% Plasmodium malariae identified. For msp1, MAD20 was the most prevalent (99%), followed by K1 (46%) allelic family, with no sample testing positive for RO33 (0%). For msp2, 3D7 allelic family was predominant (97%), followed by FC27 (10%). The multiplicity of infection of msp1 and msp2 was 2.6 and 1.1, respectively, and the mean overall multiplicity of infection was 3.7, with the total number of alleles ranging from 1 to 7., Conclusions: Given the increasing importance of antimalarial drugs in the region, the genetic diversity of P. falciparum msp1 and msp2 should be regularly monitored with respect to treatment outcomes and/or efficacy studies in regions, where there are ongoing changes in the malaria epidemiology.
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- 2020
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16. Predominant secondary dengue infection among Vietnamese adults mostly without warning signs and severe disease.
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Lytton SD, Nematollahi G, van Tong H, Xuan Anh C, Hung HV, Hoan NX, Diez G, Schumacher T, Landt O, Melchior W, Fuchs D, Toan NL, Velavan TP, and Song LH
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- Adult, Antibodies, Viral blood, Coinfection blood, Coinfection diagnosis, Coinfection epidemiology, Dengue blood, Dengue diagnosis, Dengue epidemiology, Dengue Virus classification, Dengue Virus genetics, Dengue Virus isolation & purification, Enzyme-Linked Immunosorbent Assay methods, Female, Humans, Immunoglobulin G blood, Immunoglobulin G immunology, Immunoglobulin M blood, Male, Middle Aged, RNA, Viral genetics, Serogroup, Vietnam epidemiology, Young Adult, Coinfection virology, Dengue virology, Dengue Virus physiology
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Background: The morbidity in dengue fever is dependent on the dengue virus (DENV) serotypes, the patient age, predisposing immunogenic markers and the frequency of primary and secondary infections. This study aims to distinguish acute primary from secondary dengue infections of Vietnamese adults and to assess the association of viremia and anti-dengue immunoglobulin levels with clinical outcomes., Study Design: Viral RNA, dengue serotypes and levels of anti-dengue IgM and IgG of hospitalized adult cases were determined in EDTA-plasma samples prospectively collected during three consecutive years of dengue infection in Hanoi. Patients admitted to hospital within 7 days of their 1st reported fever were included. Primary infections were anti-dengue IgG enzyme-linked immunosorbent assay (ELISA) negative on both day of hospital entry (day 0) and day two or three of hospitalization (day 2 or 3) with a positive anti-dengue IgM on either day 0 or day 2 or 3 hospitalization. The secondary infections were anti-dengue IgG ELISA positive on both day 0 and day 2 or 3 with positive anti-dengue IgM ELISA on either day 0 or day 2 or 3., Results: The hospitalized dengue fever cases between October 2016 and March 2019 were predominantly secondary infections (74%, 68% and 77%, respectively) with DENV-1 (60% and 65%) and DENV-2 (22% and 26%) serotypes determined in the latter two years. The viremia in primary infection was significantly higher than that in secondary infection (P < 0.01) and positively correlated with the days of hospital stay. In secondary infections, platelet counts were lower than in primary infections (P = 0.04) and IgG levels in secondary infection negatively correlated with platelet counts (Spearman's r = -0.22, P < 0.01)., Conclusions: Our results indicate high rates of secondary infection with DENV1 and DENV2 serotypes. Anti-dengue immunoglobulins negatively correlate with hospital stay and platelet counts with few warning signs or severe disease. Further investigations of specific antibodies in adults which predict auto-inflammatory activity after the recovery from dengue infection are warranted., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2020
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17. Complement protein levels and MBL2 polymorphisms are associated with dengue and disease severity.
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Giang NT, van Tong H, Quyet D, Hoan NX, Nghia TH, Nam NM, Hung HV, Anh DT, Van Mao C, Son HA, Meyer CG, Velavan TP, and Toan NL
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- Adolescent, Adult, Aged, Aged, 80 and over, Complement C2 analysis, Complement C5 analysis, Complement C5a analysis, Disease Progression, Female, Follow-Up Studies, Gene Expression Regulation, Genotype, Haplotypes, Humans, Male, Middle Aged, Prognosis, Severe Dengue blood, Severe Dengue genetics, Severe Dengue virology, Severity of Illness Index, Vietnam epidemiology, Young Adult, Biomarkers analysis, Dengue Virus isolation & purification, Immunologic Factors blood, Mannose-Binding Lectin blood, Mannose-Binding Lectin genetics, Polymorphism, Genetic, Severe Dengue epidemiology
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The complement system may be crucial during dengue virus infection and progression to severe dengue. This study investigates the role of MBL2 genetic variants and levels of MBL in serum and complement proteins in Vietnamese dengue patients. MBL2 genotypes (- 550L/H, MBL2 codon 54), MBL2 diplotypes (XA/XO, YA/XO) and MBL2 haplotypes (LXPB, HXPA, XO) were associated with dengue in the study population. The levels of complement factors C2, C5, and C5a were higher in dengue and dengue with warning signs (DWS) patients compared to those in healthy controls, while factor D levels were decreased in dengue and DWS patients compared to the levels determined in healthy controls. C2 and C5a levels were associated with the levels of AST and ALT and with WBC counts. C9 levels were negatively correlated with ALT levels and WBC counts, and factor D levels were associated with AST and ALT levels and with platelet counts. In conclusions, MBL2 polymorphisms are associated with dengue in the Vietnamese study population. The levels of the complement proteins C2, C4b, C5, C5a, C9, factor D and factor I are modulated in dengue patients during the clinical course of dengue.
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- 2020
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18. Proinflammatory Cytokines Are Modulated in Vietnamese Patients with Dengue Fever.
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Tuyen TT, Viet NT, Hang NT, Giang NT, Anh DD, Anh DT, Hung HV, Quyet D, Toan NL, Cam TD, and Van Tong H
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- Adolescent, Adult, Aged, Aged, 80 and over, Asian People, Female, Host Microbial Interactions, Humans, Interleukin-12 blood, Interleukin-12 immunology, Interleukin-1beta blood, Interleukin-1beta immunology, Male, Middle Aged, Tumor Necrosis Factor-alpha blood, Tumor Necrosis Factor-alpha immunology, Vietnam epidemiology, Young Adult, Cytokines blood, Cytokines immunology, Dengue immunology, Dengue Virus immunology
- Abstract
The clinical outcome of dengue is due to a complex interplay between dengue virus (DENV) and host immune factors, including complement and cytokine systems. Proinflammatory cytokines are mainly produced by monocytes in response to infectious pathogens. This study investigated the levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1 beta (IL-1β), and IL-12 in Vietnamese patients with dengue, and their correlations with the clinical outcome of dengue infection in 156 patients clinically classified as dengue without warning signs (DWS-, n = 87), dengue with warning signs (DWS+, n = 62), and severe dengue (SD, n = 7) patients as well as in 60 healthy controls (HCs). Serum TNF-α, IL-1β, and IL-12 levels were quantified by enzyme-linked immunosorbent assay (ELISA). The results showed that TNF-α, IL-1β, and IL-12 levels were significantly increased in dengue patients compared with HCs ( p < 0.0001). TNF-α levels were significantly correlated with white blood cells and platelet counts ( r
s = 0.52, 0.2; p < 0.0001, p = 0.018, respectively). IL-1β levels were correlated with red blood cells counts and the levels of aspartate aminotransferase and alanine aminotransferase ( rs = 0.23, 0.21, 0.23; p = 0.004, 0.012, 0.005, respectively). The results suggest that these three proinflammatory cytokines are associated with the clinical outcome of dengue and could play roles in the pathogenesis of the disease.- Published
- 2020
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19. Clinical significance of combined circulating TERT promoter mutations and miR-122 expression for screening HBV-related hepatocellular carcinoma.
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Trung NT, Hoan NX, Trung PQ, Binh MT, Van Tong H, Toan NL, Bang MH, and Song LH
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- Adult, Aged, Aged, 80 and over, Carcinoma, Hepatocellular blood, Carcinoma, Hepatocellular virology, Female, Humans, Liver Neoplasms blood, Liver Neoplasms virology, Male, Middle Aged, Promoter Regions, Genetic genetics, Young Adult, Carcinoma, Hepatocellular genetics, Gene Expression Regulation, Neoplastic, Hepatitis B virus physiology, Liver Neoplasms genetics, MicroRNAs genetics, Mutation, Telomerase genetics
- Abstract
Telomerase reverse-transcriptase (TERT) gene promoter mutations in circulating cell-free DNA (cfDNA) as well as the levels of circulating microRNA-122 (miR-122) have been reported as potential noninvasive biomarkers for several. This study evaluates the diagnostic performance of potent biomarker-based panels composing of serological AFP, miR-122 and circulating TERT promoter mutations for screening HBV-related HCC. TERT promoter mutations (C228T and C250T) and miR-122 expression were assessed in the plasma samples from 249 patients with HBV-related liver diseases by nested PCR and qRT-PCR assays, respectively. The diagnostic values of TERT promoter mutations, miR-122 expression and biomarker-based panels were assessed by computation of the area under the curve (AUC). Nested-PCR assays were optimized to detect C228T and C250T mutations in TERT promoter with detection limit of 1%. The common hotspot C228T was observed in 22 HCC cases. The triple combinatory panel (AFP@TERT@miR-122) acquired the best diagnostic value to distinguish HCC from CHB (AUC = 0.98), LC (AUC = 0.88) or non-HCC (LC + CHB, AUC = 0.94) compared to the performance of double combinations or single biomarkers, respectively. Notably, among patients with AFP levels≤20 ng/μl, the double combination panel (TERT@miR-122) retains satisfactory diagnostic performance in discriminating HCC from the others (HCC vs. CHB, AUC = 0.96; HCC vs. LC, AUC = 0.88, HCC vs. non-HCC, AUC = 0.94). The triple combination panel AFP@TERT@miR-122 shows a better diagnostic performance for screening HCC in HBV patients, regardless of AFP levels. The newly established panels can be a potential application in clinical practice in Vietnamese setting.
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- 2020
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20. Neopterin levels and Kyn/Trp ratios were significantly increased in dengue virus patients and subsequently decreased after recovery.
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Geisler S, Lytton SD, Toan NL, Nghia TH, Nam NM, Hung HV, Son NT, Anh DT, Tuyen HT, Tien TV, Quyet D, Van Tong H, Hoan NX, Song LH, Pallerla SR, Gostner JM, Fuchs D, and Velavan TP
- Subjects
- Adolescent, Adult, Child, Dengue virology, Dengue Virus genetics, Dengue Virus isolation & purification, Female, Follow-Up Studies, Humans, Male, Middle Aged, RNA, Viral analysis, Young Adult, Dengue blood, Kynurenine blood, Neopterin blood, Tryptophan blood
- Abstract
Objectives: During dengue fever, a pronounced gamma-interferon immune response produces neopterin and promotes tryptophan degradation by the enzyme indoleamine-2,3-dioxygenase 1 (IDO-1). Activated IDO-1 is indicated by an increased kynurenine to tryptophan ratio (Kyn/Trp) in patients., Methods: Plasma levels of neopterin, kynurenine, and tryptophan were measured in 72 hospitalized dengue virus (DENV) patients and 100 healthy individuals. Plasma levels of neopterin, kynurenine, and tryptophan were also measured prospectively in a second cohort of 13 DENV patients; on the day of hospitalization, on day 2-3 at discharge, and 7-10 days after discharge. DENV RNA positivity was determined by qualitative and quantitative methodologies., Results: DENV RNA-positive patients presented significantly higher levels of neopterin (mean 36.5nmol/l) and Kyn/Trp ratios (mean 102μmol/mmol) compared to DENV RNA-negative individuals. A significant correlation between neopterin levels and Kyn/Trp ratios was observed in both DENV RNA-positive (Spearman's rho=0.37, p< 0.01) and DENV RNA-negative (Spearman's rho=0.89, p<0.001) patients. Kyn/Trp ratios were negatively correlated with platelet counts (Spearman's rho=-0.43, p<0.01) and positively correlated with liver enzymes: AST (Spearman's rho=0.68, p<0.01) and ALT (Spearman's rho=0.51, p<0.05). In addition, the follow-up data presented a significant decrease in neopterin levels and Kyn/Trp ratios within 10 days after hospital entry., Conclusions: Neopterin levels and Kyn/Trp ratios were significantly increased in DENV patients and subsequently decreased after recovery., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2020
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21. Combination of Vaccine Strain Measles Virus and Nimotuzumab in the Treatment of Laryngeal Cancer.
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Toan NL, Hang NT, Luu NK, VAN Mao C, VAN Ba N, Xuan NT, Cam TD, Yamamoto N, VAN Tong H, and Son HA
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- Animals, Cell Line, Tumor, Chlorocebus aethiops, Combined Modality Therapy, Humans, Measles Vaccine, Mice, Nude, Vero Cells, Antibodies, Monoclonal, Humanized therapeutic use, Antineoplastic Agents therapeutic use, Laryngeal Neoplasms therapy, Measles virus, Oncolytic Virotherapy, Oncolytic Viruses
- Abstract
Background/aim: This study aims to investigate whether the combination of oncolytic viruses with chemoradiotherapy or other therapies is a promising strategy for cancer treatment., Materials and Methods: The anticancer effects of measles virus (MeV) in combination with nimotuzumab in the treatment of laryngeal cancer were evaluated in vitro and in nude mice inoculated with Hep2 tumors. MTT assay and flow cytometry were used to examine cell death., Results: Laryngeal cancer cells treated with MeV+nimotuzumab combination had a significantly lower survival rate compared to those treated with MeV or nimotuzumab alone (p<0.0001). In an animal model bearing human laryngeal tumor, the treated group had a higher survival rate (60%) compared to a untreated group (20%) (p<0.05), and the survival rate of the group treated with MeV+nimotuzumab combination was higher compared to the groups received single treatment., Conclusion: The MeV+nimotuzumab combination has greater anticancer activities in both laryngeal cancer cells and an animal model., (Copyright© 2019, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)
- Published
- 2019
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22. NTCP S267F variant associates with decreased susceptibility to HBV and HDV infection and decelerated progression of related liver diseases.
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Binh MT, Hoan NX, Van Tong H, Sy BT, Trung NT, Bock CT, Toan NL, Song LH, Bang MH, Meyer CG, Kremsner PG, and Velavan TP
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Alanine Transaminase metabolism, Alleles, Aspartate Aminotransferases metabolism, Carcinoma, Hepatocellular diagnosis, Carcinoma, Hepatocellular genetics, Case-Control Studies, Coinfection, Disease Progression, Female, Genetic Predisposition to Disease, Genotype, Hepatitis B genetics, Hepatitis D genetics, Humans, Liver Cirrhosis diagnosis, Liver Cirrhosis genetics, Liver Diseases genetics, Liver Neoplasms diagnosis, Liver Neoplasms genetics, Male, Middle Aged, RNA, Viral isolation & purification, Risk Factors, Sequence Analysis, DNA, Vietnam epidemiology, Young Adult, Genetic Variation, Hepatitis B epidemiology, Hepatitis D epidemiology, Liver Diseases diagnosis, Organic Anion Transporters, Sodium-Dependent genetics, Symporters genetics
- Abstract
Objectives: To determine potential associations of the rs2296651 variant (c.800C>T, S267F) of NTCP with HBV and HBV plus concomitant HDV infection as well as with the progression of related liver diseases., Methods: The S267F variant was genotyped by DNA sequencing in 620 HBV-infected patients and 214 healthy controls (HCs). Among the patients, 450 individuals were tested for HDV by a nested PCR assay. Logistic regression was applied to examine the association., Results: The S267F variant was found more frequently among HCs (16%) compared to HBV-infected (6%) and HBV-HDV co-infected patients (3%) (HBV patients vs HC: OR=0.32, P=0.00002 and HDV patients vs. HC: OR=0.17, P=0.018). The frequency of S267F variant was inversely correlated with CHB, LC or HCC patients compared with HCs (OR=0.31, P=0.001; OR=0.32, P=0.013; OR=0.34, P=0.002, respectively). S267F variant was also associated with decreased risk of the development of advanced liver cirrhosis (LC) and hepatocellular carcinoma (HCC) (Child B and C vs. Child A, OR=0.26, adjusted P=0.016; BCLC B,C,D vs. BCLC A, OR=0.038, P=0.045, respectively). In addition, patients with the genotype CT had lower levels of AST, ALT, total and direct bilirubin as well as higher platelet counts, indicating an association with a more favorable clinical outcome., Conclusion: The NTCP S267F variant of the SLC10A1 gene exhibits protective effects against HBV and HDV infection and is associated with a reduced risk of developing to advanced stages of LC and HCC., (Copyright © 2019 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2019
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23. The blood transcriptome of childhood malaria.
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Boldt ABW, van Tong H, Grobusch MP, Kalmbach Y, Dzeing Ella A, Kombila M, Meyer CG, Kun JFJ, Kremsner PG, and Velavan TP
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- Asymptomatic Diseases, Biomarkers, Child, Child, Preschool, Computational Biology methods, Erythrocyte Count, Female, Gene Expression Profiling, Humans, Infant, Malaria, Cerebral blood, Malaria, Cerebral parasitology, Malaria, Falciparum diagnosis, Male, Plasmodium falciparum, Real-Time Polymerase Chain Reaction, Reproducibility of Results, Severity of Illness Index, Cell-Free Nucleic Acids blood, Malaria, Falciparum blood, Malaria, Falciparum parasitology, Transcriptome
- Abstract
Background: Transcriptomic research of blood cell lineages supports the understanding of distinct features of the immunopathology in human malaria., Methods: We used microarray hybridization, validated by real-time RT-PCR to analyze whole blood gene expression in healthy Gabonese children and children with various conditions of Plasmodium falciparum infection, including i) asymptomatic infection, ii) uncomplicated malaria, iii) malaria associated with severe anemia and iv) cerebral malaria., Findings: Our data indicate that the expression profile of 22 genes significantly differed among the investigated groups. Immunoglobulin production, complement regulation and IFN beta signaling, in particular IRF7 and ISRE binding signatures in the corresponding genes, were most conspicuous. Down-regulation in cerebral malaria seems to rely on AhRF, GABP and HIF1 hypoxia transcription factors. ARG1, BPI, CD163, IFI27, HP and TNFAIP6 transcript levels correlated positively with lactatemia, and negatively with hemoglobin concentrations., Interpretation: Differences in gene expression profile reflect distinct immunopathological mechanisms of P. falciparum infection. They emerge as potential prognostic markers for early therapeutic measures and need to be validated further. FUND: This work was supported by a grant of the NGFN (Nationales Genomforschungsnetz 01GS0114) and by a CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil) PhD scholarship for A. B. W. Boldt. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2019
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24. Soluble fibrinogen-like protein 2 levels in patients with hepatitis B virus-related liver diseases.
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Van Tong H, Van Ba N, Hoan NX, Binh MT, Quyen DT, Son HA, Van Luong H, Quyet D, Meyer CG, Song LH, Toan NL, and Velavan TP
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- Adolescent, Adult, Aged, Aged, 80 and over, Biomarkers blood, Carcinoma, Hepatocellular complications, Case-Control Studies, Disease Progression, Female, Fibrinogen analysis, Fibrinogen genetics, Hepatitis B complications, Hepatitis B, Chronic complications, Humans, Liver Neoplasms complications, Male, Middle Aged, Solubility, Young Adult, Carcinoma, Hepatocellular blood, Fibrinogen metabolism, Hepatitis B blood, Hepatitis B virus physiology, Hepatitis B, Chronic blood, Liver Cirrhosis blood, Liver Neoplasms blood
- Abstract
Background: Clinical progression of HBV-related liver diseases is largely associated with the activity of HBV-specific T cells. Soluble fibrinogen-like protein 2 (sFGL2), mainly secreted by T cells, is an important effector molecule of the immune system., Methods: sFGL2 levels were determined by ELISA assays in sera of 296 HBV patients clinically classified into the subgroups of acute hepatitis B (AHB), chronic hepatitis B (CHB), liver cirrhosis (LC), hepatocellular carcinoma (HCC) and patients with LC plus HCC. As control group, 158 healthy individuals were included. FGL2 mRNA was quantified by qRT-PCR in 32 pairs of tumor and adjacent non-tumor liver tissues., Results: sFGL2 levels were elevated in HBV patients compared to healthy controls (P < 0.0001). In the patient group, sFGL2 levels were increased in AHB compared to CHB patients (P = 0.017). sFGL2 levels were higher in LC patients compared to those without LC (P = 0.006) and were increased according to the development of cirrhosis as staged by Child-Pugh scores (P = 0.024). Similarly, HCC patients had increased sFGL2 levels compared to CHB patients (P = 0.033) and FGL2 mRNA was up-regulated in tumor tissues compared to adjacent non-tumor tissues (P = 0.043). In addition, sFGL2 levels were positively correlated with HBV-DNA loads and AST (Spearman's rho = 0.21, 0.25 and P = 0.006, 0.023, respectively), but reversely correlated with platelet counts and albumin levels (Spearman's rho = - 0.27, - 0.24 and P = 0.014, 0.033, respectively)., Conclusions: sFGL2 levels are induced by HBV infection and correlated with the progression and clinical outcome of HBV-related liver diseases. Thus, sFGL2 may serve as a potential indicator for HBV-related liver diseases.
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- 2018
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25. Interferon-stimulated gene 20 kDa protein serum levels and clinical outcome of hepatitis B virus-related liver diseases.
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Van Tong H, Hoan NX, Binh MT, Quyen DT, Meyer CG, Song LH, Toan NL, and Velavan TP
- Abstract
Interferon-stimulated gene 20 kDa protein (ISG20) with 3' to 5' exonuclease activity mainly targeting single-stranded RNA plays an important role in immune responses against various infectious pathogens, including hepatitis viruses. ISG20 levels were measured by ELISA assays in sera of 339 hepatitis B-virus (HBV) infected patients and 71 healthy individuals and were correlated with clinical and laboratory parameters. ISG20 mRNA was quantified by qRT-PCR in 30 pairs of hepatocellular carcinoma (HCC) tumour and adjacent non-tumour liver tissues. ISG20 levels were significantly elevated in HBV patients compared to healthy controls ( P <0.0001). In the patient group, varying ISG20 levels were associated with different forms of HBV-related liver diseases. ISG20 levels were higher in patients with HCC compared to those without HCC ( P <0.0001), and increased according to the stages of HCC ( P <0.0001). ISG20 mRNA expression was up-regulated in tumour tissues compared to the expression in adjacent non-tumour tissues ( P =0.017). Importantly, ISG20 levels were strongly correlated with the levels of AST, ALT, total and direct bilirubin among HCC patients (Pearson's r = 0.43, 0.35, 0.34, 0.3; P <0.0001, respectively). Although differences between liver cirrhosis (LC) and non-LC patients were not observed, ISG20 levels were elevated according to the progression of cirrhosis in patients with LC plus HCC ( P =0.005). In conclusions, ISG20 levels are induced by HBV infection and significantly associated with progression and clinical outcome of HBV-related liver diseases, especially in patients with HCC. ISG20 might be a potential indicator for liver injury and the clinical outcome in HBV-related HCC., Competing Interests: CONFLICTS OF INTEREST All authors have no conflicts of interest to declare.
- Published
- 2018
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26. HDV infection rates in northern Vietnam.
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Binh MT, Hoan NX, Van Tong H, Giang DP, Sy BT, Toan NL, Song LH, Bang MH, Wedemeyer H, Meyer CG, Kremsner PG, Bock CT, and Velavan TP
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- Adolescent, Adult, Aged, Aged, 80 and over, Child, Female, Hepatitis D genetics, Hepatitis D virology, Hepatitis Delta Virus genetics, Humans, Male, Middle Aged, Phylogeny, Prevalence, Vietnam epidemiology, Young Adult, Hepatitis D epidemiology, Hepatitis Delta Virus isolation & purification, RNA, Viral genetics
- Abstract
Hepatitis D caused by the hepatitis delta virus (HDV) is a serious health problem in many regions of the world. A total of 546 HBV-infected patients were enrolled from 2013 to 2015 and classified clinically into the subgroups of chronic hepatitis B (CHB, n = 191), liver cirrhosis (LC, n = 147) and hepatocellular carcinoma (HCC, n = 208). The patients were screened for HDV-RNA by nested PCR assays. HDV genotypes were assessed by direct sequencing, followed by phylogenetic analysis. HDV-RNA was identified in 13% (71/546) of HBV-infected patients. The highest HDV prevalence was found in the LC group (19.7%), followed by the HCC (12%) and CHB (8.9%) groups (P = 0.017). HDV/HBV coinfections were significantly associated with a rather unfavourable clinical outcome, in particular with LC development compared to HBV monoinfection. Phylogenetic analyses indicated that the genotype HDV1 was, with a prevalence of 91%, by far the most common genotype in Vietnam, followed by HDV2 with 9%. Other HDV genotypes were not observed. In accordance with previous data obtained a decade ago, our results confirm a continuing high prevalence of HDV infection in hepatitis B patients in northern Vietnam with the HDV1 genotype still being the predominant genotype. HDV nucleic acid testing to minimize the associated risk should be considered.
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- 2018
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27. Adipose tissue-derived cytokines and their correlations with clinical characteristics in Vietnamese patients with type 2 diabetes mellitus.
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Toan NL, Van Hoan N, Cuong DV, Dung NV, Dung PT, Hang NT, Dieu DTH, Chung DT, Son HA, Phong PX, Lenon GB, Van De D, and Van Tong H
- Abstract
Background: Adipokines are involved in the pathogenesis of metabolic disorders including obesity and type 2 diabetes mellitus (T2DM). This study investigates the levels of leptin, resistin, visfatin, secreted frizzled-related protein 5 (SFRP5), monocyte chemoattractant protein-1 (MCP-1) and retinol-binding protein 4 (RBP4) and their correlations with clinical parameters of overweight and T2DM., Methods: We recruited overweight 50 patients with T2DM, 88 non-overweight patients with T2DM, 29 overweight and 100 non-overweight individuals devoid of T2DM for this study. The levels of studied adipokines were measured by enzyme-linked immunosorbent assay and correlated with clinical parameters., Results: The levels of MCP-1 and SFRP5 were decreased while visfatin and RBP4 levels were increased in patients with T2DM compared to those in the control individuals ( P < 0.01). Among patients with T2DM, leptin and resistin levels were higher while RBP4 levels were lower in patients with overweight T2DM compared to those in patients with non-overweight T2DM ( P < 0.0001, 0.019 and 0.05, respectively). Leptin and MCP-1 levels were correlated with HOMA-IR, QUICKI and HOMA-β. Leptin/MCP-1 ratio was correlated with insulin levels, HOMA-IR and HOMA-β indexes. Resistin/RBP4, visfatin/MCP-1 and MCP-1/RBP4 ratios were strongly correlated with the levels of fasting glucose, HbA1c and HOMA-β. In addition, ROC curve analyses indicated a diagnostic potential of resistin/RBP4 and MCP-1/RBP4 indexes for T2DM (AUC = 0.81 and 0.83, respectively) and β-cell function (AUC = 0.76 and 0.74, respectively)., Conclusions: Adipokines (leptin, resistin, visfatin, SFRP5, MCP-1, and RBP4) are associated with overweight and T2DM and may serve as a potential prognostic marker and therapeutic intervention for overweight-related T2DM.
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- 2018
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28. Combination of Vaccine-Strain Measles and Mumps Viruses Enhances Oncolytic Activity against Human Solid Malignancies.
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Son HA, Zhang L, Cuong BK, Van Tong H, Cuong LD, Hang NT, Nhung HTM, Yamamoto N, and Toan NL
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- Animals, Chlorocebus aethiops, Humans, Male, Mice, Mice, Inbred BALB C, Mice, Nude, Neoplasms pathology, Neoplasms virology, Tumor Cells, Cultured, Vero Cells, Xenograft Model Antitumor Assays, Cytopathogenic Effect, Viral, Measles virus physiology, Mumps virus physiology, Neoplasms therapy, Oncolytic Virotherapy methods
- Abstract
Oncolytic measles and mumps viruses (MeV, MuV) have a potential for anti-cancer treatment. We examined the anti-tumor activity of MeV, MuV, and MeV-MuV combination (MM) against human solid malignancies (HSM). MeV, MuV, and MM targeted and significantly killed various cancer cell lines of HSM but not normal cells. MM demonstrated a greater anti-tumor effect and prolonged survival in a human prostate cancer xenograft tumor model compared to MeV and MuV. MeV, MuV, and MM significantly induced the expression of immunogenic cell death markers and enhanced spleen-infiltrating immune cells. In conclusion, MM combination significantly improves the treatment of human solid malignancies.
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- 2018
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29. Clinical utility of an optimised multiplex real-time PCR assay for the identification of pathogens causing sepsis in Vietnamese patients.
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Tat Trung N, Van Tong H, Lien TT, Van Son T, Thanh Huyen TT, Quyen DT, Hoan PQ, Meyer CG, and Song LH
- Subjects
- Bacteria classification, Bacteria genetics, Blood Culture, Humans, Middle Aged, Sensitivity and Specificity, Vietnam, Young Adult, Bacteria isolation & purification, Multiplex Polymerase Chain Reaction methods, Real-Time Polymerase Chain Reaction methods, Sepsis diagnosis, Sepsis microbiology
- Abstract
Introduction: For the identification of bacterial pathogens, blood culture is still the gold standard diagnostic method. However, several disadvantages apply to blood cultures, such as time and rather large volumes of blood sample required. We have previously established an optimised multiplex real-time PCR method in order to diagnose bloodstream infections., Material and Methods: In the present study, we evaluated the diagnostic performance of this optimised multiplex RT-PCR in blood samples collected from 110 septicaemia patients enrolled at the 108 Military Central Hospital, Hanoi, Vietnam., Results: Positive results were obtained by blood culture, the Light Cylcler-based SeptiFast
® assay and our multiplex RT-PCR in 35 (32%), 31 (28%), and 31 (28%) samples, respectively. Combined use of the three methods confirmed 50 (45.5%) positive cases of bloodstream infection, a rate significantly higher compared to the exclusive use of one of the three methods (P=0.052, 0.012 and 0.012, respectively). The sensitivity, specificity and area under the curve (AUC) of our assay were higher compared to that of the SeptiFast® assay (77.4%, 86.1% and 0.8 vs. 67.7%, 82.3% and 0.73, respectively). Combined use of blood culture and multiplex RT-PCR assay showed a superior diagnostic performance, as the sensitivity, specificity, and AUC reached 83.3%, 100%, and 0.95, respectively. The concordance between blood culture and the multiplex RT-PCR assay was highest for Klebsiella pneumonia (100%), followed by Streptococcus spp. (77.8%), Escherichia coli (66.7%), Staphylococcus spp. (50%) and Salmonella spp. (50%). In addition, the use of the newly established multiplex RT-PCR assay increased the spectrum of identifiable agents (Acintobacter baumannii, 1/32; Proteus mirabilis, 1/32)., Conclusion: The combination of culture and the multiplex RT-PCR assay provided an excellent diagnostic accomplishment and significantly supported the identification of causative pathogens in clinical samples obtained from septic patients., (Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.)- Published
- 2018
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30. KIR-HLA distribution in a Vietnamese population from Hanoi.
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Amorim LM, van Tong H, Hoan NX, Vargas LB, Ribeiro EMSF, Petzl-Erler ML, Boldt ABW, Toan NL, Song LH, Velavan TP, and Augusto DG
- Subjects
- Adult, Asia, Southeastern, Asian People, Female, Gene Frequency, Humans, Male, Middle Aged, Polymorphism, Genetic, Vietnam, Genotype, HLA-B Antigens genetics, HLA-C Antigens genetics, Killer Cells, Natural immunology, Receptors, KIR genetics
- Abstract
The KIR (killer cell immunoglobulin-like receptors) gene family codifies a group of receptors that recognize human leukocyte antigens (HLA) and modulate natural killer (NK) cells response. Genetic diversity of KIR genes and HLA ligands has not yet been deeply investigated in South East Asia. Here, we characterized KIR gene presence and absence polymorphism of 14 KIR genes and two pseudogenes, as well as the frequencies of the ligands HLA-Bw4, HLA-C1 and HLA-C2 in a Vietnamese population from Hanoi (n = 140). Genotyping was performed by polymerase chain reaction with specific sequence primers (PCR-SSP). We compared KIR frequencies and performed principal component analysis with 43 worldwide populations of different ancestries. KIR carrier frequencies in Vietnamese were similar to those reported for Thai and Chinese Han, but differed significantly from other geographically close populations such as Japanese and South Korean. This similarity was also observed in KIR gene-content genotypes and is in accordance with the origin from Southern China and Thailand proposed for the Vietnamese population. The frequencies of HLA ligands observed in Vietnamese did not differ from those reported for other East-Asian populations (p > .05). Studies regarding KIR-HLA in populations are of prime importance to understand their evolution, function and role in diseases., (Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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31. Differential contribution of interleukin-10 promoter variants in malaria and schistosomiasis mono- and co-infections among Nigerian children.
- Author
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Adedoja A, Hoan NX, van Tong H, Adukpo S, Tijani DB, Akanbi AA 2nd, Meyer CG, Ojurongbe O, and Velavan TP
- Subjects
- Adolescent, Animals, Child, Child, Preschool, Coinfection, Female, Humans, Interleukin-10, Male, Nigeria, Promoter Regions, Genetic, Malaria, Falciparum genetics, Plasmodium falciparum genetics, Polymorphism, Genetic, Schistosoma haematobium genetics, Schistosomiasis haematobia genetics
- Abstract
Objective: Interleukin-10 (IL-10) is an anti-inflammatory cytokine produced by Th1 cells and macrophages. The rationale of this study was to examine and validate possible contributions of IL-10 promoter polymorphisms in sub-Saharan Africa in children infected with either Plasmodium falciparum or Schistosoma haematobium and in children co-infected with both parasites., Materials and Methods: A total of 309 Nigerian children aged 4-15 years were recruited. The study group consisted of individuals infected either with P. falciparum (n = 76) or S. haematobium (n = 94) in mono-infections, a group of children co-infected with both P. falciparum and S. haematobium (n = 62) and matched healthy controls (n = 77). The IL-10 promoter polymorphisms -1082G/A, -819C/T and -592C/A were genotyped by direct sequencing., Results: The frequencies of the IL-10 -1082GG genotype, the -1082G allele and haplotype GCC (positions -1082, -819 and -592) were higher in children infected with P. falciparum than in healthy controls, indicating that the -1082GG genotype and the -1082G allele and the GCC haplotype are associated with increased susceptibility to malaria infection (OR = 3.4, 95% CI = 1.2-10.8, P = 0.02; OR = 2.5, 95% CI = 1.1-3.4, P = 0.02; OR = 3.8, 95% CI = 2.0-7.2, P = 0.0001, respectively). Children with the -1082GG genotype had a higher parasitaemia than children with the -1082AA or -1082AG genotypes (P = 0.0017). Haplotype GCC occurred more frequently in children infected with S. haematobium, while haplotype GTA was less frequent than in controls (OR = 2.2, 95% CI = 1.2-4.4, P = 0.017 and OR = 0.1, 95% CI = 0.02-0.5, P = 0.0004, respectively). No differences in the frequencies of IL-10 promoter polymorphisms were observed between children with P. falciparum-S. haematobium co-infections and healthy controls., Conclusion: Although IL-10 promoter polymorphisms are not associated with P. falciparum and S. haematobium co-infection, variant -1082G/A and haplotype GCC are associated with malaria, whereas the IL-10 haplotypes GCC and GTA are associated with schistosomiasis., (© 2017 John Wiley & Sons Ltd.)
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- 2018
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32. Human genetic factors in tuberculosis: an update.
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van Tong H, Velavan TP, Thye T, and Meyer CG
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- Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Tuberculosis microbiology, Mycobacterium tuberculosis, Polymorphism, Genetic, Tuberculosis genetics
- Abstract
Tuberculosis (TB) is a major threat to human health, especially in many developing countries. Human genetic variability has been recognised to be of great relevance in host responses to Mycobacterium tuberculosis infection and in regulating both the establishment and the progression of the disease. An increasing number of candidate gene and genome-wide association studies (GWAS) have focused on human genetic factors contributing to susceptibility or resistance to TB. To update previous reviews on human genetic factors in TB we searched the MEDLINE database and PubMed for articles from 1 January 2014 through 31 March 2017 and reviewed the role of human genetic variability in TB. Search terms applied in various combinations were 'tuberculosis', 'human genetics', 'candidate gene studies', 'genome-wide association studies' and 'Mycobacterium tuberculosis'. Articles in English retrieved and relevant references cited in these articles were reviewed. Abstracts and reports from meetings were also included. This review provides a recent summary of associations of polymorphisms of human genes with susceptibility/resistance to TB., (© 2017 John Wiley & Sons Ltd.)
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- 2017
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33. Pyruvate Kinase and Fcγ Receptor Gene Copy Numbers Associated With Malaria Phenotypes.
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Faik I, van Tong H, Lell B, Meyer CG, Kremsner PG, and Velavan TP
- Subjects
- Adult, Case-Control Studies, Child, GPI-Linked Proteins genetics, Gabon, Genetic Predisposition to Disease, Humans, Phenotype, Polymorphism, Single Nucleotide, Severity of Illness Index, Gene Dosage, Malaria genetics, Pyruvate Kinase genetics, Receptors, IgG genetics
- Abstract
Genetic factors are associated with susceptibility to many infectious diseases and may be determinants of clinical progression. Gene copy number variation (CNV) has been shown to be associated with phenotypes of numerous diseases, including malaria. We quantified gene copy numbers of the pyruvate kinase, liver, and red blood cell (PKLR) gene as well as of the Fcγ receptor 2A and Fcγ receptor 2C (FCGR2A, FCGR2C) and Fcγ receptor 3 (FCGR3) genes using real-time quantitative polymerase chain reaction (RT-qPCR) assays in Gabonese children with severe (n = 184) or and mild (n = 189) malaria and in healthy Gabonese and white individuals (n = 76 each). The means of PKLR, FCGR2A, FCGR2C, and FCGR3 copy numbers were significantly higher among children with severe malaria compared to those with mild malaria (P < .002), indicating that a surplus of copies of those genes is significantly associated with malaria severity. Copy numbers of the FCGR2A and FCGR2C genes were significantly lower (P = .005) in Gabonese individuals compared with white individuals. In conclusion, CNV of the PKLR, FCGR2A, FCGR2C, and FCGR3 genes is associated with malaria severity, and our results provide evidence for a role of CNV in host responses to malaria., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2017
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34. SOCS3 genetic variants and promoter hypermethylation in patients with chronic hepatitis B.
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Hoan NX, Van Tong H, Giang DP, Cuong BK, Toan NL, Wedemeyer H, Bock CT, Kremsner PG, Song LH, and Velavan TP
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Alleles, Carcinoma, Hepatocellular complications, Carcinoma, Hepatocellular genetics, Female, Gene Expression Regulation, Neoplastic, Gene Frequency, Genetic Predisposition to Disease genetics, Genotype, Haplotypes, Hepatitis B virus physiology, Hepatitis B, Chronic complications, Hepatitis B, Chronic virology, Humans, Liver Cirrhosis complications, Liver Cirrhosis genetics, Liver Neoplasms complications, Liver Neoplasms genetics, Male, Middle Aged, Viral Load, Young Adult, DNA Methylation, Hepatitis B, Chronic genetics, Polymorphism, Single Nucleotide, Promoter Regions, Genetic genetics, Suppressor of Cytokine Signaling 3 Protein genetics
- Abstract
The clinical manifestations of hepatitis B viral infection (HBV) include chronic hepatitis B (CHB), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). The contribution of negative regulator suppressor of cytokine signaling-3 (SOCS3) promoter variants in HBV disease and SOCS3 hypermethylation in tumor tissues were investigated. The SOCS3 promoter region was screened for polymorphisms in 878 HBV patients and in 272 healthy individuals. SOCS3 promoter methylation was examined by bisulfite sequencing. SOCS3 mRNA expression was quantified in 37 tumor and adjacent non-tumor liver tissue specimens. The minor allele rs12953258A was associated with increased susceptibility to HBV infection (OR=1.3, 95%CI=1.1-1.6, adjusted P=0.03). The minor allele rs111033850C and rs12953258A were observed in increased frequencies in HCC and LC patients compared to CHB patients (HCC: OR=1.7, 95%CI=1.1-2.9, adjusted P=0.046; LC: OR=1.4, 95%CI=1.1-1.9, adjusted P=0.017, respectively). HBV patients with rs111033850CC major genotype had decreased viral load (P=0.034), whereas the rs12953258AA major genotype contributed towards increased viral load (P=0.029). Tumor tissues revealed increased hypermethylation compared to adjacent non-tumor tissues (OR=5.4; 95%CI= 1.9-17.1; P=0.001). Increased SOCS3 expression was observed in HBV infested tumor tissues than non-HBV related tumor tissues (P=0.0048). SOCS3 promoter hypermethylation was associated with relatively low mRNA expression in tumor tissues (P=0.0023). In conclusion, SOCS3 promoter variants are associated with HBV susceptibility and SOCS3 hypermethylation stimulates HCC development.
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- 2017
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35. Parasite Infection, Carcinogenesis and Human Malignancy.
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van Tong H, Brindley PJ, Meyer CG, and Velavan TP
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- Animals, Host-Parasite Interactions, Humans, Neoplasms diagnosis, Neoplasms metabolism, Parasitic Diseases metabolism, Carcinogenesis, Neoplasms etiology, Parasitic Diseases complications, Parasitic Diseases parasitology
- Abstract
Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in areas holoendemic for malaria. The initiation of Plasmodium falciparum related endemic Burkitt lymphoma requires additional transforming events induced by the Epstein-Barr virus. Observations suggest that Strongyloides stercoralis may be a relevant co-factor in HTLV-1-related T cell lymphomas. This review provides an overview of the mechanisms of parasitic infection-induced carcinogenicity., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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36. Significance of nucleic acid testing in diagnosis and treatment of post-neurosurgical meningitis caused by multidrug-resistant Acinetobacter baumannii: a case report.
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Trung NT, Van Son T, Quyen DT, Anh DT, Sang VV, Lam NX, Manh ND, Duong VP, Cuong BT, Tuyen QD, Chinh NX, Hoan PQ, Van Tong H, Meyer CG, and Song LH
- Subjects
- Acinetobacter Infections drug therapy, Adult, Anti-Bacterial Agents therapeutic use, Cross Infection diagnosis, Cross Infection drug therapy, Drug Resistance, Multiple, Bacterial, Humans, Male, Meningitis drug therapy, Postoperative Complications drug therapy, Postoperative Complications microbiology, Acinetobacter Infections diagnosis, Acinetobacter baumannii isolation & purification, Meningitis diagnosis, Neurosurgery, Polymerase Chain Reaction methods, Postoperative Complications diagnosis
- Abstract
Background: Neurosurgery may pose the risk of patients' developing nosocomial meningitis caused by infection with hospital pathogens. Rapid detection of the causative pathogens is essential for selecting the appropriate antibiotic treatment. However, the classical culture-based detection of bacterial infection is time-consuming and often fails to establish the correct diagnosis. Molecular techniques offer improved diagnostic means to guide the proper antibiotic therapy., Case Presentation: A 32-year-old Vietnamese man underwent neurosurgery and subsequently developed meningitis. The classical bacterial culture method failed to detect any infectious agents, whereas polymerase chain reaction-based assays identified Acinetobacter baumannii as the causative pathogen. In addition, detection of the acquired extended-spectrum beta-lactamase gene VEB and carbapenem resistance genes NDM-1 and IMP suggested that the isolated A. baumannii strain was multidrug resistant. Upon the establishment of the correct diagnosis, an adequate treatment regimen was chosen and he recovered completely., Conclusions: This case report demonstrates the usefulness of the molecular approach as an important addendum and alternative to culture-based diagnosis in order to detect the pathogen causative for meningitis, including the indicators for resistance.
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- 2016
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37. Interferon-stimulated gene 15 in hepatitis B-related liver diseases.
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Hoan NX, Van Tong H, Giang DP, Toan NL, Meyer CG, Bock CT, Kremsner PG, Song LH, and Velavan TP
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- Adolescent, Adult, Aged, Aged, 80 and over, Carcinoma, Hepatocellular blood, Carcinoma, Hepatocellular complications, Cytokines blood, Female, Gene Frequency, Genetic Predisposition to Disease genetics, Genotype, Hepatitis B virus physiology, Hepatitis B, Chronic virology, Humans, Liver Cirrhosis blood, Liver Cirrhosis complications, Liver Neoplasms blood, Liver Neoplasms complications, Male, Middle Aged, Ubiquitins blood, Young Adult, Carcinoma, Hepatocellular genetics, Cytokines genetics, Hepatitis B, Chronic complications, Liver Cirrhosis genetics, Liver Neoplasms genetics, Polymorphism, Single Nucleotide, Ubiquitins genetics
- Abstract
This study investigates the association of Interferon-stimulated gene 15 (ISG15) polymorphisms, ISG15 serum levels and expression with HBV-related liver diseases. The ISG15 promoter and the two exons of the gene were screened for polymorphisms in 766 HBV-infected patients and in 223 controls. Soluble ISG15 levels were measured by ELISA. ISG15 mRNA expression was quantified by qRT-PCR in 36 tumor and adjacent non-tumor tissues. The exon 2 allele rs1921A was found associated with decreased progression of HBV-related liver diseases (LC vs. CHB: OR = 0.6, 95%CI = 0.4-0.8, adjusted P = 0.003; HCC vs. CHB: OR = 0.6, 95%CI = 0.4-0.9, adjusted P = 0.005). The rs1921AA genotype was associated with low levels of AST, ALT and total bilirubin, but with high prothrombin levels (P < 0.05). ISG15 serum levels were higher among HBV patients compared to controls (P < 0.0001) and positively associated with HBV-related liver diseases, with highest levels among LC patients. ISG15 levels were correlated with HBV-DNA loads (P = 0.001). In non-tumor tissues from HCC patients, ISG15 mRNA expression was increased in HBV compared to non-HBV infection (P = 0.016). The ISG15 rs1921 variant and ISG15 expression are associated with HBV-related liver diseases. Taken together, ISG15 appears to be a proviral factor involved in HBV replication and triggering progression of HBV-related liver diseases.
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- 2016
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38. Association of vitamin D deficiency with hepatitis B virus - related liver diseases.
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Hoan NX, Khuyen N, Binh MT, Giang DP, Van Tong H, Hoan PQ, Trung NT, Anh DT, Toan NL, Meyer CG, Kremsner PG, Velavan TP, and Song LH
- Abstract
Background: As an immune modulator, vitamin D is involved in various pathophysiological mechanisms in a plethora of diseases. This study aims to correlate the vitamin D deficiency status and clinical progression of liver diseases associated with hepatitis B virus (HBV) infection in patients in Vietnam and to compare it to healthy controls., Methods: We quantified the levels of total vitamin D [25-(OH) D2 and D3] in serum samples from 400 HBV patients (chronic hepatitis B infection [CHB], n = 165; HBV-associated liver cirrhosis [LC], n = 127; HBV-associated hepatocellular carcinoma [HCC], n = 108) and 122 unrelated healthy controls (HC). Univariate and multivariate analyses were performed in order to determine the association between vitamin D levels and distinct clinical parameters., Results: The prevalence of vitamin D inadequacy (<30 ng/mL) was high among healthy individuals (81.7 %) as well as in HBV patients (84.3 %). Vitamin D deficiency (<20 ng/ml) or severe deficiency (<10 ng/ml) was observed more frequently among HBV patients (52 %) and subgroups (CHB, 47.8 %; LC, 54.4 %; HCC, 55.3 %) compared to the control group (32.5 %) (P < 0.001). Vitamin D levels and HBV-DNA load were strongly and inversely correlated (rho = -0.57, P < 0.0001). Multivariate regression analysis also revealed an independent association of HBV-DNA loads with low vitamin D levels (P = 0.0004). In addition, reduced vitamin D levels were associated with significant clinical progression of LC (Child-Pugh C versus Child-Pugh A, P = 0.0018; Child-Pugh C versus Child-Pugh B, P = 0.016)., Conclusions: Vitamin D deficiency was observed in the majority of HBV-infected patients and associated with adverse clinical outcomes. Our findings suggest that substitution of vitamin D may be a supportive option in the treatment of chronic liver diseases, in particular of HBV-associated disorders.
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- 2016
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39. Hepatitis E Virus Mutations: Functional and Clinical Relevance.
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van Tong H, Hoan NX, Wang B, Wedemeyer H, Bock CT, and Velavan TP
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- Antiviral Agents pharmacology, Antiviral Agents therapeutic use, Genetic Variation, Genotype, Hepatitis E diagnosis, Hepatitis E drug therapy, Hepatitis E prevention & control, Hepatitis E virus classification, Hepatitis E virus drug effects, Humans, Open Reading Frames, RNA, Viral, Recombination, Genetic, Viral Vaccines genetics, Viral Vaccines immunology, Virus Replication, Genome, Viral, Hepatitis E etiology, Hepatitis E virus physiology, Mutation
- Abstract
Hepatitis E virus (HEV) infection is a major cause of acute hepatitis and affects more than 20 million individuals, with three million symptomatic cases and 56,000 recognized HEV-related deaths worldwide. HEV is endemic in developing countries and is gaining importance in developed countries, due to increased number of autochthone cases. Although HEV replication is controlled by the host immune system, viral factors (especially specific viral genotypes and mutants) can modulate HEV replication, infection and pathogenesis. Limited knowledge exists on the contribution of HEV genome variants towards pathogenesis, susceptibility and to therapeutic response. Nonsynonymous substitutions can modulate viral proteins structurally and thus dysregulate virus-host interactions. This review aims to compile knowledge and discuss recent advances on the casual role of HEV heterogeneity and its variants on viral morphogenesis, pathogenesis, clinical outcome and antiviral resistance., (Copyright © 2016 Forschungsgesellschaft für Arbeitsphysiologie und Arbeitschutz e.V. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
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40. Enrichment of bacterial DNA for the diagnosis of blood stream infections.
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Trung NT, Hien TT, Huyen TT, Quyen DT, Van Son T, Hoan PQ, Phuong NT, Lien TT, Binh MT, Van Tong H, Meyer CG, Velavan TP, and Song le H
- Subjects
- Bacteremia blood, Bacteremia microbiology, Escherichia coli genetics, Escherichia coli Infections blood, Escherichia coli Infections microbiology, Humans, Real-Time Polymerase Chain Reaction, Sensitivity and Specificity, Bacteremia diagnosis, DNA, Bacterial analysis, Escherichia coli isolation & purification, Escherichia coli Infections diagnosis, RNA, Ribosomal, 16S analysis
- Abstract
Background: Blood cultures are commonly employed to identify bacterial pathogens causing sepsis. PCR assays to diagnose septicemia require extraction of bacterial DNA from blood samples and thus, delay the initiation of appropriate antimicrobial treatment. The presence of abundant human DNA may hamper the sensitivity of PCR in the detection of bacteria., Methods: We used serial dilutions of E. Coli spiked pseudo-blood-sepsis samples to develop a simple method that combines the use of a polar detergent solvent and adjustment of the basic pH to remove human DNA. A 16S rRNA gene-based screening algorithm was established to differentiate Gram-positive and Gram-negative groups of bacteria and the family of Enterobacteriaceae. A stringent validation with appropriate controls was implemented. The method of human DNA removal was then applied on 194 sepsis blood samples and 44 cerebrospinal fluid (CSF) samples by real-time PCR., Results: This uncomplicated and straightforward approach allows to remove up to 98 % of human DNA from peripheral blood of septic patients. The inhibitory effect of human DNA is efficiently prevented and the detection limit of real-time PCR is increased to 10 E. Coli CFUs/ml. This sensitivity is 10 times higher compared to conventional real-time PCR assays. The classical blood culture detected 58/194 (30 %) of sepsis and 9/44 (21 %) of CSF samples. Out of the 194 blood samples tested, the conventional real-time PCR targeting 13 common sepsis causing pathogens correctly detected the bacterial DNA in 16/194 (8 %) only and 14/44 (32 %) in cerebrospinal fluid samples. Our newly established approach was able to provide correct diagnoses in 78 (40 %) of the 194 blood samples and in 14 (32 %) of the CSF samples. The combination of both blood cultures and our technique raised the rate of sepsis diagnoses to 112/194 (58 %). Of the total group tested positive, 46 (24 %) cases showed overlap with the classical methodology., Conclusion: We report a simple optimized in-house protocol for removal of human DNA from blood sepsis samples as a pre-analytical tool to prepare DNA for subsequent PCR assays. With the detection increase of our in-house DNA removal approach, subsequent PCR assays can reach detection limits of 10 E. coli CFUs/ml and significantly improve the diagnostic rate in blood sepsis cases.
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- 2016
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41. Low MBL-associated serine protease 2 (MASP-2) levels correlate with urogenital schistosomiasis in Nigerian children.
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Ojurongbe O, Antony JS, Van Tong H, Meyer CG, Akindele AA, Sina-Agbaje OR, Kremsner PG, and Velavan TP
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- Adolescent, Adult, Animals, Case-Control Studies, Child, Child, Preschool, Female, Genotype, Haplotypes, Humans, Male, Middle Aged, Nigeria, Polymorphism, Genetic, Schistosoma haematobium genetics, Schistosomiasis haematobia genetics, Young Adult, Mannose-Binding Protein-Associated Serine Proteases analysis, Schistosoma haematobium isolation & purification, Schistosomiasis haematobia blood
- Abstract
Objectives: The human mannose-binding lectin (MBL) and ficolins (FCN) are involved in pathogen recognition in the first line of defence. They support activation of the complement lectin cascade in the presence of MBL-associated serine protease 2 (MASP-2), a protein that cleaves the C4 and C2 complement components. Recent studies found that distinct MBL2 and FCN2 promoter variants and their corresponding serum levels are associated with relative protection from urogenital schistosomiasis., Methods: We investigated the contribution of MASP-2 levels and MASP2 polymorphisms in a Nigerian study group, of 163 individuals infected with Schistosoma haematobium and 183 healthy subjects., Results: MASP-2 serum levels varied between younger children (≤12 years) and older children (>12 years) and adults (P = 0.0001). Younger children with a patent infection had significantly lower MASP-2 serum levels than uninfected children (P = 0.0074). Older children and adults (>12 years) with a current infection had higher serum MASP-2 levels than controls (P = 0.032). MBL serum levels correlated positively with MASP-2 serum levels (P = 0.01). MASP2 secretor haplotypes were associated with MASP-2 serum levels in healthy subjects. The heterozygous MASP2 p.P126L variant was associated with reduced serum MASP-2 levels (P = 0.01)., Conclusions: The findings indicate that higher MASP-2 serum levels are associated with relative protection from urogenital schistosomiasis in Nigerian children., (© 2015 John Wiley & Sons Ltd.)
- Published
- 2015
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42. Analysis of genetic variants in the IL4 promoter and VNTR loci in Indian patients with Visceral Leishmaniasis.
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Mishra A, Jha AN, van Tong H, Singh VK, Gomes CE, Singh L, Velavan TP, and Thangaraj K
- Subjects
- Adult, Case-Control Studies, Female, Gene Frequency, Genetic Association Studies, Humans, India, Leishmania immunology, Leishmania pathogenicity, Leishmaniasis, Visceral genetics, Linkage Disequilibrium genetics, Male, Polymorphism, Single Nucleotide, Immunity, Cellular genetics, Interleukin-4 genetics, Leishmaniasis, Visceral immunology, Minisatellite Repeats genetics, Promoter Regions, Genetic genetics
- Abstract
Visceral Leishmaniasis (VL) is the most severest form of Leishmaniasis and resistance to infection is mediated by cellular immune responses. Interleukin 4 (IL-4) orchestrates of Th2 and Th1 immune responses during infections. In this study, we aimed to investigate possible association between three functional IL-4 polymorphisms -590C/T (rs2243250), -34C/T (rs2070874) and 70bp VNTR (rs79071878 in intron3) with VL in an Indian cohort comprising of 197 VL patients and 193 healthy controls. The three investigated IL-4 polymorphisms were in strong linkage disequilibrium. The investigated IL-4 alleles, genotypes and the reconstructed haplotypes were not significantly distributed between the VL patients and healthy controls. Our study signifies no possible association of functional IL-4 polymorphisms with Indian VL and postulate other vital genes involved in the IL-4 pathway may provide genetic clues to elucidate of IL-4 regulation and immune-pathogenesis during VL., (Copyright © 2014 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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43. LRRK2 and RIPK2 variants in the NOD 2-mediated signaling pathway are associated with susceptibility to Mycobacterium leprae in Indian populations.
- Author
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Marcinek P, Jha AN, Shinde V, Sundaramoorthy A, Rajkumar R, Suryadevara NC, Neela SK, van Tong H, Balachander V, Valluri VL, Thangaraj K, and Velavan TP
- Subjects
- Alleles, Female, Haplotypes genetics, Haplotypes immunology, Humans, India epidemiology, Leprosy epidemiology, Leprosy immunology, Leucine-Rich Repeat Serine-Threonine Protein Kinase-2, Male, Nod2 Signaling Adaptor Protein immunology, Polymorphism, Genetic genetics, Polymorphism, Genetic immunology, Protein Serine-Threonine Kinases immunology, Receptor-Interacting Protein Serine-Threonine Kinase 2 immunology, Signal Transduction immunology, Th1 Cells immunology, Genetic Predisposition to Disease, Leprosy genetics, Mycobacterium leprae, Nod2 Signaling Adaptor Protein genetics, Protein Serine-Threonine Kinases genetics, Receptor-Interacting Protein Serine-Threonine Kinase 2 genetics, Signal Transduction genetics
- Abstract
In recent years, genome wide association studies have discovered a large number of gene loci that play a functional role in innate and adaptive immune pathways associated with leprosy susceptibility. The immunological control of intracellular bacteria M. leprae is modulated by NOD2-mediated signaling of Th1 responses. In this study, we investigated 211 clinically classified leprosy patients and 230 ethnically matched controls in Indian population by genotyping four variants in NOD2 (rs9302752A/G), LRRK2 (rs1873613A/G), RIPK2 (rs40457A/G and rs42490G/A). The LRRK2 locus is associated with leprosy outcome. The LRRK2 rs1873613A minor allele and respective rs1873613AA genotypes were significantly associated with an increased risk whereas the LRRK2 rs1873613G major allele and rs1873613GG genotypes confer protection in paucibacillary and leprosy patients. The reconstructed GA haplotypes from RIPK2 rs40457A/G and rs42490G/A variants was observed to contribute towards increased risk whereas haplotypes AA was observed to confer protective role. Our results indicate that a possible shared mechanisms underlying the development of these two clinical forms of the disease as hypothesized. Our findings confirm and validates the role of gene variants involved in NOD2-mediated signalling pathways that play a role in immunological control of intracellular bacteria M. leprae.
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- 2013
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44. Mannose-binding lectin and susceptibility to schistosomiasis.
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Antony JS, Ojurongbe O, van Tong H, Ouf EA, Engleitner T, Akindele AA, Sina-Agbaje OR, Adeyeba AO, Kremsner PG, and Velavan TP
- Subjects
- Adolescent, Adult, Aged, Case-Control Studies, Child, Child, Preschool, Cohort Studies, Female, Humans, Male, Mannose-Binding Lectin deficiency, Middle Aged, Nigeria, Young Adult, Genetic Predisposition to Disease, Mannose-Binding Lectin blood, Mannose-Binding Lectin genetics, Schistosomiasis haematobia immunology
- Abstract
Background: Human ficolin 2 (encoded by FCN2) and mannose-binding lectin (encoded by MBL2) bind to specific pathogen-associated molecular patterns, activate the complement lectin cascade in a similar manner, and are associated with several infectious diseases. Our recently published study established certain FCN2 promoter variants and ficolin-2 serum levels as protective factors against schistosomiasis., Methods: We used the Nigerian cohort from our recently published study, which included 163 Schistosoma haematobium-infected individuals and 183 matched healthy subjects, and investigated whether MBL deficiency and MBL2 polymorphisms are associated with schistosomiasis., Results: MBL serum levels were significantly higher in controls and were associated with protection (P < .0001). The -550H minor allele was significantly associated with protection (P = .03), and the heterozygous genotypes -550HL were observed to confer protection (P = .03). The MBL2*HYPA haplotype was significantly associated with protection (P = .03), with significantly higher serum MBL levels in controls (P = .00073). The heterozygous 6-bp deletion in the promoter was observed to be a susceptibility factor in schistosomiasis (P = .03)., Conclusions: In agreement with findings from our recently published study, the findings reported here support the observation that MBL is also associated with protection in schistosomiasis.
- Published
- 2013
- Full Text
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45. IL-4 haplotype -590T, -34T and intron-3 VNTR R2 is associated with reduced malaria risk among ancestral indian tribal populations.
- Author
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Jha AN, Singh VK, Kumari N, Singh A, Antony J, van Tong H, Singh S, Pati SS, Patra PK, Singh R, Toan NL, Song le H, Assaf A, Messias-Reason IJ, Velavan TP, Singh L, and Thangaraj K
- Subjects
- Adolescent, Adult, Base Sequence, Brazil, Female, Gene Frequency, Genetic Predisposition to Disease ethnology, Genetic Predisposition to Disease genetics, Genotype, Humans, India, Malaria, Falciparum ethnology, Male, Middle Aged, Molecular Sequence Data, Risk Factors, Sequence Homology, Amino Acid, Syria, Vietnam, Young Adult, Haplotypes, Interleukin-4 genetics, Introns genetics, Malaria, Falciparum genetics, Minisatellite Repeats genetics
- Abstract
Background: Interleukin 4 (IL-4) is an anti-inflammatory cytokine, which regulates balance between T(H)1 and T(H)2 immune response, immunoglobulin class switching and humoral immunity. Polymorphisms in this gene have been reported to affect the risk of infectious and autoimmune diseases., Methods: We have analyzed three regulatory IL-4 polymorphisms; -590C>T, -34C>T and 70 bp intron-3 VNTR, in 4216 individuals; including: (1) 430 ethnically matched case-control groups (173 severe malaria, 101 mild malaria and 156 asymptomatic); (2) 3452 individuals from 76 linguistically and geographically distinct endogamous populations of India, and (3) 334 individuals with different ancestry from outside India (84 Brazilian, 104 Syrian, and 146 Vietnamese)., Results: The -590T, -34T and intron-3 VNTR R2 alleles were found to be associated with reduced malaria risk (P<0.001 for -590C>T and -34C>T, and P = 0.003 for VNTR). These three alleles were in strong LD (r²>0.75) and the TTR2 (-590T, -34T and intron-3 VNTR R2) haplotype appeared to be a susceptibility factor for malaria (P = 0.009, OR = 0.552, 95% CI = 0.356 -0.854). Allele and genotype frequencies differ significantly between caste, nomadic, tribe and ancestral tribal populations (ATP). The distribution of protective haplotype TTR2 was found to be significant (χ²₃ = 182.95, p-value <0.001), which is highest in ATP (40.5%); intermediate in tribes (33%); and lowest in caste (17.8%) and nomadic (21.6%)., Conclusions: Our study suggests that the IL-4 polymorphisms regulate host susceptibility to malaria and disease progression. TTR2 haplotype, which gives protection against malaria, is high among ATPs. Since they inhabited in isolation and mainly practice hunter-gatherer lifestyles and exposed to various parasites, IL-4 TTR2 haplotype might be under positive selection.
- Published
- 2012
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46. Mucosal delivery of antigens using adsorption to bacterial spores.
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Huang JM, Hong HA, Van Tong H, Hoang TH, Brisson A, and Cutting SM
- Subjects
- Adsorption, Animals, Anthrax prevention & control, Antibodies, Bacterial blood, Clostridium Infections prevention & control, Female, Mice, Mice, Inbred BALB C, Protein Binding, T-Lymphocytes immunology, Tetanus prevention & control, Antigens, Bacterial chemistry, Antigens, Bacterial immunology, Bacillus subtilis chemistry, Bacillus subtilis immunology, Spores, Bacterial chemistry, Spores, Bacterial immunology
- Abstract
The development of new-generation vaccines has followed a number of strategic avenues including the use of live recombinant bacteria. Of these, the use of genetically engineered bacterial spores has been shown to offer promise as both a mucosal as well as a heat-stable vaccine delivery system. Spores of the genus Bacillus are currently in widespread use as probiotics enabling a case to be made for their safety. In this work we have discovered that the negatively charged and hydrophobic surface layer of spores provides a suitable platform for adsorption of protein antigens. Binding can be promoted under conditions of low pH and requires a potent combination of electrostatic and hydrophobic interactions between spore and immunogen. Using appropriately adsorbed spores we have shown that mice immunised mucosally can be protected against challenge with tetanus toxin, Clostridium perfringens alpha toxin and could survive challenge with anthrax toxin. In some cases protection is actually greater than using a recombinant vaccine. Remarkably, killed or inactivated spores appear equally effective as live spores. The spore appears to present a bound antigen in its native conformation promoting a cellular (T(h)1-biased) response coupled with a strong antibody response. Spores then, should be considered as mucosal adjuvants, most similar to particulate adjuvants, by enhancing responses against soluble antigens. The broad spectrum of immune responses elicited coupled with the attendant benefits of safety suggest that spore adsorption could be appropriate for improving the immunogenicity of some vaccines as well as the delivery of biotherapeutic molecules.
- Published
- 2010
- Full Text
- View/download PDF
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