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Background: The most commonly used oral anticoagulant is acenocoumarol with the brand name is Sintrom and recently, warfarin with the brand name is Coumadin has begun to be used. Anticoagulation with vitamin K antagonists faces two main obstacles: the narrow therapeutic range and the effectiveness of the drug varies by many factors. Objective: " Current status of coagulation disorders in the treatment of anticoagulants with vitamin K antagonists. Understanding some factors affecting the goal of anticoagulant treatment". Method: Cross-sectional, retrospective, descriptive analysis of drug use and influencing factors of patients diagnosed with coagulopathy admitted to the emergency department at Hanoi Heart Hospital from April 2020 to August 2021. Results: There were 675 patients admitted to the hospital with blood clotting disorders. The average age is 60,17±10,13, the youngest is 30, the oldest is 90; 63 patients, accounting for 9.42%, need to be hospitalized for inpatient treatment; There are 108 patients, accounting for 16%, with bleeding and 18 patients, accounting for 2.7%, with thromboembolism or valve obstruction. Conclusion: Coagulation disorders during treatment with vitamin K antagonist anticoagulants is a common condition in the emergency department. However, the complication rate is not high. There are many factors that affect the patient's treatment goals and the drug use is a fairly common factor.

Background: Although there are many advances in the diagnosis and resuscitation of patients with cardiogenic shock, the mortality rate is still high, especially for patients with cardiogenic shock due to complications of acute myocardial infarction, the mortality rate can be up to 50 - 70%. Objective: "Evaluate the effectiveness of clinical, subclinical and complications of V-A ECMO in patients with cardiogenic shock". Method: Retrospective analysis of patients diagnosed with cardiogenic shock supported by V-A ECMO revascularization from October 2018 and June 2020; Analyze the significance of V-A ECMO with the clinical outcome prognosis and and complications of V-A ECMO. Results: There were 23 patients hospitalized for cardiogenic shock, they have used the V-A ECMO. The mean age was 53,5±17,6, the minimum age was 13, the oldest was 76. The shortest hospital stay time was 3.5 day and the longest treatment time is 32 days. There were 15 patients alive, accounting for 65.2%, 8 patients died, accounting for 35.8%. The percentage of patients living in the group of myocarditis reached the highest rate. Common complications in patients supported by V-A ECMO are left ventricular volume overload and infection. Conclusion: V-A ECMO is a treatment option for life-threatening cardiogenic shock that has not responded to other therapies.

The 1H-NMR method for simultaneous quantification of methanol, ethanol and their metabolic products (formic acid and acetic acid) in human plasma was established. The effect of protein in plasma sample was removed by 25% trichloroacetic acid (TCA) with the ratio of TCA and plasma sample at 1/5 (v/v). The small amount of D2O (estimated 1/10 v/v) was chosen due to the effect of water signal was eliminated by using the advance water suppression with NOESY pulse sequence. The different analytical parameters such as linearity, precision, accuracy, and specificity, instrument detection limit (IDL) and instrument quantification limit (IQL) were validated. The instrument detection limit of four compounds in blank plasma varied from 0.68 (for methanol) to 2.88 mg/L (for formic acids). The average recoveries of concentration in dynamic ranges were found to be 96 to105%. The good linearity between concentration calculated by integrated signal and measured obtained by calibration curves confirmed that concentration of analytes in plasma can be directly determined from the 1H-NMR signal. The proposed method has been successfully applied for direct determination of five compounds in 9 patient’s plasma samples with the satisfactory results compared to GC/FID method. The analytical procedure can be useful for diagnosis and evaluation of treatment of methanol poisoning in Vietnamese hospitals.

Several kinds of electrocatalyst based on platinum, palladium, and nickel with glassy carbon substrate were successfully synthesized by electrodeposition method, and then applied for water electrolysis in alkaline media. Surface morphology of materials was investigated with scanning electron microscopy method. Energy-dispersive X-ray spectroscopy was used to find the content of each metal in bimetallic materials. The result showed that the number of noble metals was moderately decreased while the catalytic activities were slightly better than pure metal electrodes. Linear sweep voltammetry measurement was taken in KOH 1M solution to find the overvoltage of hydrogen evolution reaction and cyclic voltammetry method in 0.01M K3[Fe(CN)6]: 0.01M K4[Fe(CN)6] in 0.1M KOH was used to determine the reversible capacity of material electrodes. The linear sweep voltammetry measurements confirmed that the activities of new catalysts are higher than the origin materials. The binary catalyst of Pt-Ni can replace platinum for hydrogen evolution reaction in alkaline medium. Notably, the replacement of platinum atoms with palladium and nickel atoms, and the combination of good properties of them leads to improve the catalytic activity, and in the same time to decrease the catalyst cost. Once again, the electrochemical parameters open up a new prospect for the hydrogen produce.

Coating an alloys film onto a metallic surface could dramatically improve the surface quality. This report studies the microstructure and intermixing phenomena of Ni50Co50 film deposited on Ni(001) substrate with flat, asperity and trench Ni surfaces by molecular dynamics (MD) simulation. The effects of the film thickness and loading velocity on the mechanical properties and deformation behaviours of the sample are also surveyed by indentation. The results represent that the intermixing and lattice structure of the film is enhanced after annealing. Moreover, the sample hardness is improved as the deposited Ni50Co50 film when the film thickness rising from 18 to 38 Å. In contrast, the structure transformation rate and dislocations density of the sample decrease when the Ni50Co50 film becomes thicker. Interestingly, the plastic deformation rate and dislocation density of the sample at the trench surface are higher than the flat one. Besides, the increase of the loading velocity gives rise to the plastic deformation and the local stress rates. The dislocation density of the Ni50Co50/Ni sample is reduced if the loading speed is high enough.

Leprosy is the second most prevalent mycobacterial disease globally. Despite the existence of an effective therapy, leprosy incidence has consistently remained above 200,000 cases per year since 2010. Numerous host genetic factors have been identified for leprosy that contribute to the persistently high case numbers. In the past decade, genetic epidemiology approaches, including genome-wide association studies (GWAS), identified more than 30 loci contributing to leprosy susceptibility. However, GWAS loci commonly encompass multiple genes, which poses a challenge to define causal candidates for each locus. To address this problem, we hypothesized that genes contributing to leprosy susceptibility differ in their frequencies of rare protein-altering variants between cases and controls. Using deep resequencing we assessed protein-coding variants for 34 genes located in GWAS or linkage loci in 555 Vietnamese leprosy cases and 500 healthy controls. We observed 234 nonsynonymous mutations in the targeted genes. A significant depletion of protein-altering variants was detected for the IL18R1 and BCL10 genes in leprosy cases. The IL18R1 gene is clustered with IL18RAP and IL1RL1 in the leprosy GWAS locus on chromosome 2q12.1. Moreover, in a recent GWAS we identified an HLA-independent signal of association with leprosy on chromosome 6p21. Here, we report amino acid changes in the CDSN and PSORS1C2 genes depleted in leprosy cases, indicating them as candidate genes in the chromosome 6p21 locus. Our results show that deep resequencing can identify leprosy candidate susceptibility genes that had been missed by classic linkage and association approaches., Author summary Leprosy is an infectious disease caused by the Mycobacterium leprae. The development of an effective treatment in the 1980s contributed to the decline of leprosy prevalence. Still, around 200 thousand new leprosy cases are detected every year. In the past two decades, multiple studies have identified genetic variants increasing the risk of developing leprosy, particularly using genome-wide association studies (GWAS). However, GWAS loci commonly encompass multiple genes, which poses a challenge in identifying the best candidates contributing to susceptibility. This limits the usefulness of the genetic findings for understanding leprosy pathogenesis. Our study tested if the accumulation of rare protein-altering variants in genes located in GWAS loci could distinguish the best functional candidates. We found that the burden of amino acid changes in IL18R1 and BCL10 was significantly different between leprosy cases and healthy controls, suggesting these genes as functional candidates in leprosy pathogenesis.

In this study, poly(styrene-co-vinyl benzyl trimethyl ammonium chloride) with different styrene to vinyl benzyl chloride ratio (3:1, 1:1, 1:2) have been synthesized. The formation ofproducts was confirmed by Fourier transform infrared spectrophotometry (FTIR) and nuclear magnetic resonance spectra (1H NMR). Then, anion exchange membranes were prepared by combination of poly(styrene-co-vinyl benzyl trimethyl ammonium hydroxide) and poly (vinyl alcohol) The obtained membranes were evaluated for their own conductivity, anion exchange capacity, and thermal decomposition. The results showed that the anion exchange membrane produced from copolymer with styrene to vinyl benzyl chloride ratio 1: 2 exhibited good hydroxide conductivity of 7 mS/cm, ion exchange capacity was 0.65mmol/g and stability to 200oC. Keywords Membrane, poly(vinyl alcohol), copolymer, conductivity, fuel cell. References [1] D. J. Kim, C. H. Park, S. Y. Nam, Characterization of a soluble poly(ether ether ketone) anion exchange membrane for fuel cell application, Int. J. Hydrogen Energy 41 (2016) 7649-7658. https:// doi.org/10.1016/j. ijhydene.2015.12.088[2] J. Fu, J. Qiao, H. Lv, J. Ma, X.-Z. Yuan, H. Wang, Alkali doped poly(vinyl alcohol) (PVA) for anion-exchange membrane fuel cells - Ionic conductivity, chemical stability and FT-IR characterizations, Alkaline Electrochem. Power Sources 25 (2010) 15–23. http://doi.rog/10.1149/ 1.3315169[3] D. L. Zugic, I. M. Perovic, V. M. Nikolic, S. L. Maslovara, M. P. Marceta Kaninski, Enhanced Performance of the Solid Alkaline Fuel Cell Using PVA-KOH Membrane, Int. J. Electrochem. Sci. 8 (2013) 949-957. [4] Jikihara, R. Ohashi, Y. Kakihana, M. Higa, and K. Kobayashi, Electrodialytic transport properties of anion-exchange membranes prepared from poly(vinyl alcohol) and poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride), Membranes (Basel) 3 (2013) 1-15. http: //doi.rog/10.3390/membranes3010001[5] S. Vengatesan, S. Santhi, S. Jeevanantham, G. Sozhan, Quaternized poly(styrene-co-vynylbenzyl choloride) anion exchange membranes for alkaline water electrolysers, Journal of Power Sources 84 (2015) 361-368. https://doi.org/10.1016/j.jpowsour. 2015.02.118[6] L. E. Shmukler, N. V. Thuc, and L. P. Safonova, Conductivity and thermal stability of proton-conducting electrolytes at confined geometry of polymeric gel, Ionics 19 (2013) 701-707. https:// doi.org/10.1007/s11581-012-0800-2[7] D//A. Lewandowski, K. Skorupska, J. Malinska, Novel poly(vinyl alcohol)–KOH–H2O alkaline polymer electrolyte, Solid State Ionics 133 (2000) 265-271. https://doi.org/10.1016/S0167-2738(00) 00733-5 [8] Jun F, Y. Wu, Y. Zhang, M. Lyu, J. Zhao, Novel anion exchange membranes based on pyridinium groups and fluoroacrylate for alkaline anion exchange membrane fuel cells, Int. J. Hydrogen Energy 40 (2015) 12392-12399. https://doi.org/10. 1016/j.ijhydene.2015.07.074[9] Géraldine M, M. Wessling, K. Nijmeijer Anion exchange membranes for alkaline fuel cells: A review, Journal of Membrane Science, 377(2011) 1-35. https://doi.org/10.1016/j.memsci.2011.04.043.

Significance Type-1 reactions (T1R) are pathological immune responses in leprosy and a frequent cause of peripheral nerve damage. Employing a candidate gene approach combined with deep resequencing, we identified amino acid mutations in the E3 ligase Parkin and the polyfunctional kinase LRRK2 that were associated with T1R. This finding directly linked both proteins with the extent of the immune response in an infectious disease. Moreover, amino acids associated with T1R mutations were significantly enriched for mutations found in patients suffering from Parkinson’s disease (PD). These findings confirm Parkin and LRRK2 as 2 key inflammatory regulators and suggest that T1R and PD share overlapping pathways of pathogenesis., Type-1 reactions (T1R) are pathological inflammatory episodes and main contributors to nerve damage in leprosy. Here, we evaluate the genewise enrichment of rare protein-altering variants in 7 genes where common variants were previously associated with T1R. We selected 474 Vietnamese leprosy patients of which 237 were T1R-affected and 237 were T1R-free matched controls. Genewise enrichment of nonsynonymous variants was tested with both kernel-based (sequence kernel association test [SKAT]) and burden methods. Of the 7 genes tested 2 showed statistical evidence of association with T1R. For the LRRK2 gene an enrichment of nonsynonymous variants was observed in T1R-free controls (PSKAT-O = 1.6 × 10−4). This genewise association was driven almost entirely by the gain-of-function variant R1628P (P = 0.004; odds ratio = 0.29). The second genewise association was found for the Parkin coding gene PRKN (formerly PARK2) where 7 rare variants were enriched in T1R-affected cases (PSKAT-O = 7.4 × 10−5). Mutations in both PRKN and LRRK2 are known causes of Parkinson’s disease (PD). Hence, we evaluated to what extent such rare amino acid changes observed in T1R are shared with PD. We observed that amino acids in Parkin targeted by nonsynonymous T1R-risk mutations were also enriched for mutations implicated in PD (P = 1.5 × 10−4). Hence, neuroinflammation in PD and peripheral nerve damage due to inflammation in T1R share overlapping genetic control of pathogenicity.

Type-1 reactions (T1Rs) are pathological inflammatory episodes and main contributors to nerve damage in leprosy. Here, we evaluate the gene-wise enrichment of rare protein altering variants in seven genes where common variants were previously associated with T1R. We selected 474 Vietnamese leprosy-patients of which 237 were T1R-affected and 237 were T1R-free matched controls. Gene-wise enrichment of nonsynonymous variants was tested with both kernel based (SKAT) and burden methods. Of the seven genes tested two showed statistical evidence of association with T1R. For the LRRK2 gene an enrichment of nonsynonymous variants was observed in T1R-free controls (pSKAT-O= 1.6×10−4). This gene-wise association was driven almost entirely by the gain of function variant R1628P (p = 0.004; OR = 0.29). The second gene-wise association was found for the Parkin coding gene PRKN (formerly PARK2) where seven rare variants were enriched in T1R-affected cases (pSKAT-O = 7.4×10−5). Mutations in both PRKN and LRRK2 are known causes of Parkinson’s Disease (PD). Hence, we evaluated to what extent such rare amino acid changes observed in T1R are shared with PD. We observed that nonsynonymous T1R-risk mutations in Parkin were enriched for amino acid mutations implicated in PD (p = 1.5×10−4). Hence, neuro-inflammation in PD and peripheral nerve damage due to inflammation in T1R share overlapping mechanisms of pathogenicity.

Leprosy is a chronic infectious disease of the skin and peripheral nerves with a strong genetic predisposition. Recent genome-wide approaches have identified numerous common variants associated with leprosy, almost all in the Chinese population. We conducted the first family-based genome-wide association study of leprosy in 622 affected offspring from Vietnam, followed by replication in an independent sample of 1181 leprosy cases and 668 controls of the same ethnic origin. The most significant results were observed within the HLA region, in which six SNPs displayed genome-wide significant associations, all of which were replicated in the independent case/control sample. We investigated the signal in the HLA region in more detail, by conducting a multivariate analysis on the case/control sample of 319 GWAS-suggestive HLA hits for which evidence for replication was obtained. We identified three independently associated SNPs, two located in the HLA class I region (rs1265048: OR = 0.69 [0.58–0.80], combined p-value = 5.53x10-11; and rs114598080: OR = 1.47 [1.46–1.48], combined p-value = 8.77x10-13), and one located in the HLA class II region (rs3187964 (OR = 1.67 [1.55–1.80], combined p-value = 8.35x10-16). We also validated two previously identified risk factors for leprosy: the missense variant rs3764147 in the LACC1 gene (OR = 1.52 [1.41–1.63], combined p-value = 5.06x10-14), and the intergenic variant rs6871626 located close to the IL12B gene (OR = 0.73 [0.61–0.84], combined p-value = 6.44x10-8). These results shed new light on the genetic control of leprosy, by dissecting the influence of HLA SNPs, and validating the independent role of two additional variants in a large Vietnamese sample., Author summary Due to its extreme reductive evolution Mycobacterium leprae is a rare example of an essentially clonal bacterial pathogen that affects humans. However, exposed individuals display a wide diversity of symptoms reflecting the interactions between the host immune response and the bacterium. There is now accumulating evidence, in particular from genome-wide association study (GWAS), that common genetic variants play a role explaining this variability. Previous GWAS were based on case control design and almost all of them were conducted in the Chinese population. We conducted the first family-based GWAS of leprosy in the Vietnamese population and identified several genome-wide significant association signals within the HLA region. By performing a multivariate analysis in an independent case-control sample of the same ethnic origin we were able to decipher the HLA association signal and to reduce it to three independent SNPs, two in the class I and one in the class II region. We also validated two previously identified risk factors for leprosy, a missense variant in the LACC1 gene, and an intergenic variant located close to the IL12B gene. These results shed new light on the genetic control of leprosy and, in particular, on the influence of HLA SNPs in a large Vietnamese sample.

Molecular dynamics simulation is employed to analyze the effect of sliding, rolling and oscillating movements on nanotribology properties of a diamond abrasive on a silicon substrate. The abrasive oscillating mechanism is achieved by simulating megasonic vibration-assisted on the planarization process. In this paper, the effects of abrasive size, sliding velocity, depths of polishing, rolling velocity, rolling direction, oscillating amplitude and oscillating frequency on material removal are considered. The results showed that the rolling mechanism reaches the highest number of atoms removed while the suitable oscillating mechanism gains the lowest height of asperity. The oscillating movement has remarkable results in wiping out the asperity atoms, although at a high amplitude and a low frequency causing some atoms from the flat substrate stuck to the abrasive and left some surface defects. Moreover, a multi-asperities model is set up to simulate the global-scale ability of sliding, oscillating and rolling mechanisms on polishing. This model indicates the saturated behavior of the rolling mechanism, while the lowest value of the surface roughness attained by the sliding mechanism. Combining three types of removing mechanisms could create a smooth surface with a high effective removal rate on both local and global-scales.

Background. Type 1 reactions (T1R) affect a considerable proportion of patients with leprosy. In those with T1R, the host immune response pathologically overcompensates for the actual infectious threat, resulting in nerve damage and permanent disability. Based on the results of a genome-wide association study of leprosy per se, we investigated the TNFSF15 chromosomal region for a possible contribution to susceptibility to T1R. Methods. We performed a high-resolution association scan of the TNFSF15 locus to evaluate the association with T1R in 2 geographically and ethnically distinct populations: a family-based sample from Vietnam and a case-control sample from Brazil, comprising a total of 1768 subjects. Results. In the Vietnamese sample, 47 single-nucleotide polymorphisms (SNPs) overlapping TNFSF15 and the adjacent TNFSF8 gene were associated with T1R but not with leprosy. Of the 47 SNPs, 39 were cis-expression quantitative trait loci (cis-eQTL) for TNFSF8 including SNPs located within the TNFSF15 gene. In the Brazilian sample, 18 of these cis-eQTL SNPs overlapping the TNFSF8 gene were validated for association with T1R. Conclusions. Taken together, these results indicate TNFSF8 and not TNFSF15 as an important T1R susceptibility gene. Our data support the need for infection genetics to go beyond genes for pathogen control to explore genes involved in a commensurate host response.

One of the persistent challenges of genetic association studies is the replication of genetic marker-disease associations across ethnic groups. Here, we conducted high-density association mapping of PARK2/PACRG SNPs with leprosy and identified 69 SNPs significantly associated with leprosy in 198 single-case Vietnamese leprosy families. A total of 56 associated SNPs localized to the overlapping promoter regions of PARK2/PACRG. For this region, multivariate analysis identified four SNPs belonging to two major SNP bins (rs1333955, rs7744433) and two single SNP bins (rs2023004, rs6936895) that capture the combined statistical evidence (P = 1.1 × 10−5) for association among Vietnamese patients. Next, we enrolled a case–control sample of 364 leprosy cases and 370 controls from Northern India. We genotyped all subjects for 149 SNPs that capture >80 % of the genetic variation in the Vietnamese sample and found 24 SNPs significantly associated with leprosy. Multivariate analysis identified three SNPs (rs1333955, rs9356058 and rs2023004) that capture the association with leprosy (P

The proton-conducting gel electrolytes based on poly(methyl methacrylate) (PMMA) doped by acid solutions in aprotic solvents were synthesized and discussed in this work. The gel conductivity as a function on concentrations of acid and polymer as well as of molecular mass of PMMA has been analyzed. The thermal stability of electrolytes was estimated and discussed. Extreme dependence of the conductivity on concentration is found to be for the gel (at a concentration of PMMA from 5 to 15 wt.%). The increase of electrical conductivity in the concentration range from 5 to 10 wt.% of PMMA with an increase in viscosity of the system is discussed as an indication of an involvement of the polymer matrix in increasing the mobility of the charge carriers in frame of Grotthuss mechanism.

The Mitsuda reaction, a delayed granulomatous skin reaction elicited by the intradermal injection of heat-killed Mycobacterium leprae, is an in vivo test reflecting the ability to generate an immune granuloma after sensitization by diverse mycobacterial infections. Accumulating evidence for the genetic control of the Mitsuda reaction has been reported. We performed a genomewide linkage scan for the quantitative Mitsuda reaction in 19 large families from Vietnam with a history of leprosy (114 offspring). Suggestive linkage was found at chromosomal regions 2q35 (P = 9 x 10(-4) at the SLC11A1 locus) and 17q21-25 (P = 8 x 10(-4)). Interestingly, these 2 regions have been previously linked to mycobacterial infection and other granulomatous diseases.

Host genetics has an important role in leprosy, and variants in the shared promoter region of PARK2 and PACRG were the first major susceptibility factors identified by positional cloning. Here we report the linkage disequilibrium mapping of the second linkage peak of our previous genome-wide scan, located close to the HLA complex. In both a Vietnamese familial sample and an Indian case-control sample, the low-producing lymphotoxin-alpha (LTA)+80 A allele was significantly associated with an increase in leprosy risk (P = 0.007 and P = 0.01, respectively). Analysis of an additional case-control sample from Brazil and an additional familial sample from Vietnam showed that the LTA+80 effect was much stronger in young individuals. In the combined sample of 298 Vietnamese familial trios, the odds ratio of leprosy for LTA+80 AA/AC versus CC subjects was 2.11 (P = 0.000024), which increased to 5.63 (P = 0.0000004) in the subsample of 121 trios of affected individuals diagnosed before 16 years of age. In addition to identifying LTA as a major gene associated with early-onset leprosy, our study highlights the critical role of case- and population-specific factors in the dissection of susceptibility variants in complex diseases.

Background. Reversal, or type 1, leprosy reactions (T1Rs) are acute immune episodes that occur in skin and/ or nerves and are the leading cause of neurological impairment in patients with leprosy. T1Rs occur mainly in patients with borderline or multibacillary leprosy, but little is known about additional risk factors. Methods. We enrolled 337 Vietnamese patients with leprosy in our study, including 169 subjects who presented with T1Rs and 168 subjects with no history of T1Rs. A multivariate analysis was used to determine risk factors for T1R occurrence, time to T1R onset after leprosy diagnosis, and T1R sequelae after treatment. Results. Prevalence of T1Rs was estimated to be 29.1%. Multivariate analysis identified 3 clinical features of leprosy associated with T1R occurrence. Borderline leprosy subtype (odds ratio, 6.3 [95% confidence interval, 2.9-13.7] vs. polar subtypes) was the major risk factor; 2 other risk factors were positive bacillary index and presence of>5 skin lesions. In addition, age at leprosy diagnosis was a strong independent risk factor for T1Rs (odds ratio, 2.4 [95% confidence interval, 1.3-4.4] for patients aged ≥15 years old vs.

Proton-conducting gel electrolytes based on poly(methyl methacrylate) (PMMA), poly(vinylidene fluoride) (PVdF), and mixtures of PMMA with PVdF or poly(vinyl chloride) doped by acid solutions in aprotic solvents were synthesized and are discussed in this article. The gel conductivity as a function of the concentrations of acid and polymer and the polymeric matrix composition has been analyzed. Extreme dependence of the conductivity on acid and polymer concentrations was found. It was revealed that within the acid concentration range studied, the gel conductivity was higher than the conductivity of the corresponding liquid electrolytes used for the synthesis. The increase in the electrical conductivity with the growth of the systems viscosity is discussed as an indication of a certain involvement of the polymer matrix in the increase of the charge carrier mobility within the frame of a Grotthuss mechanism. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40674.

Leprosy is a debilitating infectious disease of human skin and nerves. Genetic factors of the host play an important role in the manifestation of disease susceptibility. The human NRAMP1 gene is a leprosy susceptibility candidate locus since its murine homologue Nramp1 (formerly Lsh/Ity/Bcg) controls innate resistance to Mycobacterium lepraemurium. In this study, 168 members of 20 multiplex leprosy families were genotyped for NRAMP1 alleles and 4 closely linked polymorphic markers. Highly informative haplotypes overlapping the NRAMP1 gene were constructed, and the haplotype segregation into leprosy-affected offspring was analyzed. It was observed that the segregation of NRAMP1 haplotypes into affected siblings was significantly nonrandom. This finding is consistent with the hypothesis that NRAMP1 itself is a leprosy susceptibility locus.

Leprosy is caused by infection with Mycobacterium leprae and is classified clinically into paucibacillary (PB) or multibacillary (MB) subtypes based on the number of skin lesions and the bacillary index detected in skin smears. We previously identified a major PB susceptibility locus on chromosome region 10p13 in Vietnamese families by linkage analysis. In the current study, we conducted high-density association mapping of the 9.5 Mb linkage peak on chromosome region 10p13 covering 39 genes. Using leprosy per se and leprosy subtypes as phenotypes, we employed 294 nuclear families (303 leprosy cases, 63 % MB, 37 % PB) as a discovery sample and 192 nuclear families (192 cases, 55 % MB, 45 % PB) as a replication sample. Replicated significant association signals were revealed in the genes for cubilin (CUBN) and nebulette (NEBL). In the combined sample, the C allele (frequency 0.26) at CUBN SNP rs10904831 showed association [p = 1 × 10(-5); OR 0.52 (0.38-0.7)] with MB leprosy only. Likewise, allele T (frequency 0.42) at NEBL SNP rs11012461 showed association [p = 4.2 × 10(-5); OR 2.51 (1.6-4)] with MB leprosy only. These associations remained valid for the CUBN signal when taking into account the effective number of tests performed (type I error significance threshold = 2.4 × 10(-5)). We used the results of our analyses to propose a new model for the genetic control of polarization of clinical leprosy.

To investigate the nature of the genetic component controlling susceptibility to leprosy and its subtypes, 402 nuclear families were ascertained through a leprosy patient followed at the Dermatology Hospital in Ho Chi Minh City, Vietnam; 285 families were of Vietnamese origin and 117 were of Chinese origin with a higher proportion of lepromatous forms among Chinese patients. Segregation analyses were conducted using the model developed by Abel and Bonney [(1990) Genet Epidemiol 7:391–407], which accounted for variable age of onset and time-dependent covariates. Three phenotypes were considered: leprosy per se (all forms of leprosy together), nonlepromatous leprosy, and lepromatous leprosy. For each of this phenotype, analyses were performed on the whole sample and separately on the Vietnamese and the Chinese families. The results showed that a single Mendelian gene could not account for the familial distributions of leprosy per se and its two subtypes in the whole sample. However, these results were different according to the ethnic origin of the families. In the Vietnamese subsample, there was evidence for a codominant major gene with residual familial dependences for the leprosy per se phenotype, and borderline rejection of the Mendelian transmission hypothesis for the nonlepromatous phenotype. In Chinese families, strong rejection of Mendelian transmission was obtained in the analysis of leprosy per se, and no evidence for a familial component in the distribution of the nonlepromatous phenotype was observed. For the lepromatous phenotype, the discrimination between models was poor, and no definitive conclusion could be reached. Referring to immunological data, we suggest that these results could be explained by a heterogeneity in the definition of the lepromatous phenotype. It is likely that progress in the understanding of the genetic components involved in the expression of leprosy will come from a better definition of the phenotype under study, and immunological studies are ongoing in this population to investigate this hypothesis. © Wiley-Liss, Inc.

A genomewide association study in Chinese patients with leprosy detected association signals in 16 single-nucleotide polymorphisms (SNPs) belonging to 6 loci, of which 4 are related to the NOD2 signaling pathway and are Crohn’s disease susceptibility loci. Here, we studied these 16 SNPs as potential leprosy susceptibility factors in 474 Vietnamese leprosy simplex families. We replicated SNPs at HLA-DRDQ, RIPK2, CCDC122-LACC1, and NOD2 as leprosy susceptibility factors in Vietnam. These results validated the striking overlap in the genetic control of Crohn’s disease and leprosy. Leprosy is a chronic infectious disease of the skin and peripheral nerves and continues to contribute to the public health burden in several countries [1]. The causal agent, Mycobacterium leprae, shows high host specificity and displays low genomic diversity across strains. Only a small proportion of exposed individuals become infected and develop clinically overt disease [2]. The clinical presentation of leprosy can be broadly classified into 2 groups: paucibacillary leprosy (PB), characterized by a small number of anesthetized skin lesions with a lack of detectable M. leprae bacilli, and multibacillary leprosy (MB), characterized by numerous skin lesions with an abundance of M. leprae bacilli. Susceptibility to leprosy per se and the development of the clinical subtypes depend on human genetic factors [2]. Forward human genetics has led to the positional identification of leprosy risk variants in PARK2, LTA, and HLA-C [3–5]. A genome-wide association study (GWAS) conducted in Chinese patients with leprosy identified associations in 6 genes: CCDC122, LACC1(formerly C13orf31), NOD2, TNFSF15, HLADR ,a ndRIPK2 [6]. Three of these genes (TNFSF15, NOD2, RIPK2) are part of the NOD2 signaling pathway, and 4 have been associated with Crohn’s disease (TNFSF15, NOD2, HL ADR, LACC1 )[ 7]. In addition, a trend toward association was observed for the PARK2-interacting LRRK2 gene, which is associated with both Parkinson’s disease and Crohn’s disease [6]. To assess whether these findings may be extended beyond the Chinese population, we performed an association study among 474 Vietnamese simplex families (2 parents and 1 leprosy affected child) with the 16 leprosy-associated single-nucleotide polymorphisms (SNPs) identified in the Chinese GWAS.

Experimental evidence suggested the existence of unidentified leprosy susceptibility loci in the human leukocyte antigen (HLA) complex. To identify such genetic risk factors, a high-density association scan of a 1.9mega-base (Mb) region in the HLA complex was performed. Among 682 single-nucleotide polymorphisms (SNPs), 59 were associated with leprosy (P ,.01) in 198 Vietnamese single-case leprosy families. Genotyping of these SNPs in an independent sample of 292 Vietnamese single-case leprosy families replicated the association of 12 SNPs (P ,.01). Multivariate analysis of these 12 SNPs showed that the association information could be captured by 2 intergenic HLA class I region SNPs (P 5 9.4 3 10 29 )—rs2394885 and rs2922997 (marginal multivariate P 5 2.1 3 10 27 and P 5 .0016, respectively). SNP rs2394885 tagged the HLA-C*15:05 allele in the Vietnamese population. The identical associations were validated in a third sample of 364 patients with leprosy and 371 control subjects from North India. These results implicated class I alleles in leprosy pathogenesis.

Background. Leprosy is a chronic infectious disease caused by Mycobacterium leprae. The Mitsuda reaction is a delayed granulomatous skin reaction elicited by intradermal injection of heat-killed M. leprae. Interestingly, results of the Mitsuda test are positive in the majority of individuals, even in areas not endemic for M. leprae. Like leprosy, the Mitsuda reaction is thought to be genetically controlled, but its mode of inheritance is unknown, although the role of the NRAMP1 gene has previously been reported. Methods. We conducted a segregation analysis of quantitative Mitsuda reactivity in 168 Vietnamese nuclear families ascertained through patients with leprosy. Results. We found strong evidence ( ) for a major gene controlling the Mitsuda reaction independently 9 P ! 10 of leprosy clinical status. Subsequent linkage analysis showed that this major gene was distinct from NRAMP1. Under the major-gene model, ∼12% of individuals are homozygous for the recessive predisposing allele and are predicted to display high levels of Mitsuda reactivity (mean, ∼10 mm, versus 5 mm in other individuals). Conclusion. We provide evidence that the Mitsuda reaction is controlled by a major gene. Our study paves the way for the identification of this gene and should provide novel insight into the mechanisms involved in granuloma formation, especially in M. leprae infection. Leprosy is a chronic infectious disease, caused by Mycobacterium leprae, that mainly affects skin and peripheral nerves [1]. Despite a dramatic decrease in prevalence during the past 15 years, partly due to the efficacy of multidrug therapy [2], the worldwide leprosy incidence is still approaching 500,000 novel cases/year. Whereas most infected individuals do not develop clinical disease, even after sustained exposure to M. leprae, others present a broad spectrum of clinical symptoms. Leprosy ranges from the tuberculoid form, characterized by mature, well-delineated, and well-differentiated

Leprosy is caused by Mycobacterium leprae and affects about 700,000 individuals each year1. It has long been thought that leprosy has a strong genetic component2, and recently we mapped a leprosy susceptibility locus to chromosome 6 region q25–q26 (ref. 3). Here we investigate this region further by using a systematic association scan of the chromosomal interval most likely to harbour this leprosy susceptibility locus. In 197 Vietnamese families we found a significant association between leprosy and 17 markers located in a block of approx. 80 kilobases overlapping the 5′ regulatory region shared by the Parkinson's disease gene PARK2 and the co-regulated gene PACRG. Possession of as few as two of the 17 risk alleles was highly predictive of leprosy. This was confirmed in a sample of 975 unrelated leprosy cases and controls from Brazil in whom the same alleles were strongly associated with leprosy. Variants in the regulatory region shared by PARK2 and PACRG therefore act as common risk factors for leprosy.

Leprosy, a chronic infectious disease caused by Mycobacterium leprae, affects an estimated 700,000 persons each year. Clinically, leprosy can be categorized as paucibacillary or multibacillary disease. These clinical forms develop in persons that are intrinsically susceptible to leprosy per se, that is, leprosy independent of its specific clinical manifestation. We report here on a genome-wide search for loci controlling susceptibility to leprosy per se in a panel of 86 families including 205 siblings affected with leprosy from Southern Vietnam. Using model-free linkage analysis, we found significant evidence for a susceptibility gene on chromosome region 6q25 (maximum likelihood binomial (MLB) lod score 4.31; P = 5 x 10(-6)). We confirmed this by family-based association analysis in an independent panel of 208 Vietnamese leprosy simplex families. Of seven microsatellite markers underlying the linkage peak, alleles of two markers (D6S1035 and D6S305) showed strong evidence for association with leprosy (P = 6.7 x 10(-4) and P = 5.9 x 10(-5), respectively).

The Mitsuda test, which measures the specific immune response against intradermally injected lepromin, has a high prognostic value for susceptibility or resistance to the lepromatous form of leprosy. A sib-pair linkage analysis between the Mitsuda response and the NRAMP1 gene was done among 20 nuclear families with leprosy (totaling 118 sibs) from Ho Chi Minh City, Vietnam. All family subjects were genotyped for several intragenic and flanking NRAMP1 markers, leading to the definition of a fully informative NRAMP1 haplotype. Significant linkage was observed between NRAMP1 and Mitsuda reaction when considered either as a quantitative (P

To determine the extent of HIV infection among female commercial sex workers (CSW), to identify risk factors, and to provide baseline data for developing and targeting prevention measures.A total of 968 female CSW were enrolled in a cross-sectional study from August 1995 to October 1996. Information was obtained from confidential face-to-face interview, physical examination, and laboratory testing.A total of 65.5% of female CSW reported inconsistent condom use. Overall seroprevalence was 5.2%. The highest seroprevalence (9.5%) was detected in An Giang province, a border area adjacent to Cambodia. Out of seven HIV isolates in An Giang province, six were characterized as Thai subtype E and one as subtype B. Multiple logistic regression analysis showed an independent significant association between HIV seroprevalence and the following: ageor = 30 years [odds ratio (OR), 5.1; 95% confidence interval (CI), 1.7-15.2]; high frequency of sex (20 times per week; OR, 13.5; 95% CI, 3.6-50.2); inconsistent condom use (OR, 2.8; 95% CI, 1.01-8.0; sign of genital ulcers (OR, 18.1; 95% CI, 1.8-182); venereal warts (OR, 9.0; 95% CI, 2.5-33.0); brothels as sex venue (OR, 7.0; 95% CI, 2.0-24.3); and working at the border area (OR, 5.1; 95% CI, 2.4-11.0). Brothels as work-sites were significantly related to inconsistent condom use and the socioeconomic background of clients. Only 0.5% of CSW reported injecting drug use.Female CSW at brothels who reported inconsistent condom use and ulcerous sexually transmitted disease, particularly in the border area with Cambodia, had greater risk of HIV infection. Brothels were more frequently used as sex venues in the border area and were more likely to be visited by occasional clients who were difficult to access. Drug use among female CSW in this region was rare. The development of prevention measures should be based on these results.

Leprosy reversal reactions type 1 (T1R) are acute immune episodes that affect a subset of leprosy patients and remain a major cause of nerve damage. Little is known about the relative importance of innate versus environmental factors in the pathogenesis of T1R. In a retrospective design, we evaluated innate differences in response to Mycobacterium leprae between healthy individuals and former leprosy patients affected or free of T1R by analyzing the transcriptome response of whole blood to M. leprae sonicate. Validation of results was conducted in a subsequent prospective study. We observed the differential expression of 581 genes upon exposure of whole blood to M. leprae sonicate in the retrospective study. We defined a 44 T1R gene set signature of differentially regulated genes. The majority of the T1R set genes were represented by three functional groups: i) pro-inflammatory regulators; ii) arachidonic acid metabolism mediators; and iii) regulators of anti-inflammation. The validity of the T1R gene set signature was replicated in the prospective arm of the study. The T1R genetic signature encompasses genes encoding pro- and anti-inflammatory mediators of innate immunity. This suggests an innate defect in the regulation of the inflammatory response to M. leprae antigens. The identified T1R gene set represents a critical first step towards a genetic profile of leprosy patients who are at increased risk of T1R and concomitant nerve damage., Author Summary Leprosy type 1 reversal reactions (T1R) are an important cause of nerve damage in leprosy patients and accurate prediction of patients at increased risk of T1R is a major challenge of current leprosy control. The incidence of T1R differs widely from 6% to 67% of leprosy patients in different leprosy endemic settings. Whether or not this reflects the impact of unknown environmental triggers or differences in the genetic background across ethnicities is not known. We performed a comparative transcriptome analysis between leprosy patients affected and free of T1R in response to M. leprae antigens. As the discovery sample we enrolled cured leprosy patients who had been diagnosed with T1R at the time of leprosy diagnosis and leprosy patients who had never undergone T1R (retrospective arm). Whole genome transcriptome analysis after stimulation of blood with M. leprae antigen resulted in the definition of a T1R signature gene set. We validated the T1R gene set in RNA samples obtained from T1R-free patients at the time of leprosy diagnosis and followed for 3 years for development of T1R (prospective arm). These results confirm the role of innate factors in T1R and are a first step towards a predictive genetic T1R signature.