Associations between four polymorphisms of the SLCO1B1 and effectiveness of the statins: a meta-analysis.

OBJECTIVE: Statins are the first-choice therapy for dyslipidemia, but their effectiveness can be influenced by genetic polymorphisms. This study was conducted to assess the association of variants of the solute carrier anion transporter family 1B1 (SLCO1B1) gene, which encodes a transporter involving the hepatic clearance of the statins and their therapeutic efficacy. METHOD: A systematic review was performed on four electronic databases to identify relevant studies. The pooled mean difference with 95% confidence interval (CI) in percentage change of concentration of LDL-C, total cholesterol (TC), HDL-C, and triglycerides was calculated. Heterogeneity between studies and publication bias, subgroup analyses, and sensitivity analyses were also carried out using R software. RESULTS: Twenty-one studies on 24 365 participants and four variants [rs4149056 (c.521T>C), rs2306283 (c.388A>G), rs11045819 (c.463C>A), rs4363657 (g.89595T>C)] were analyzed. A statistically significant association was found between the LDL-C-lowering effectiveness and the rs4149056 and rs11045819 in the heterozygote model; and the rs4149056, rs2306283, and rs11045819 in the homozygote model. In the subgroup analyses, non-Asian populations, simvastatin, and pravastatin showed significant associations between LDL-C-lowering efficacy and the rs4149056 or rs2306283. Significant associations between the rs2306283 and HDL-C-increasing effectiveness were found in the homozygote model. Regarding TC-reducing, significant associations were observed in the heterozygote and homozygote models of the rs11045819. There was no heterogeneity and publication bias among most studies. CONCLUSION: SLCO1B1 variants can be used as signals to predict the statins' effectiveness.

A case-control study of agricultural and behavioral factors associated with leptospirosis in Vietnam.

INTRODUCTION: Leptospirosis is a neglected disease in Vietnam. Until now, there has been limited knowledge about risk factors of this disease in Vietnam. The study was carried out to identify agricultural and behavioral factors associated with the transmission of leptospirosis in Vietnam. METHODS: This matched retrospective hospital-community-based case-control study was conducted from 1 October 2018 to 31 October 2019. We recruited cases from 11 selected government hospitals in three provinces of Vietnam, while controls were selected from the same communes of cases and matched by age (± 2 years) and sex. Microscopic agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) were applied to determine confirmed cases, while only MAT was used to identify controls with a single high MAT titer < 1:100. RESULTS: 504 participants (252 cases and 252 controls) were identified. Cultivating (OR 2.83, CI 1.38-5.79), animal farming (OR 8.26, CI 2.24-30.52), pig owners (OR 10.48, CI 5.05-21.73), cat owners (OR 2.62, CI 1.49-4.61) and drinking unboiled water (OR 1.72, CI 1.14 -2.59, p = 0.010) were significantly associated with human leptospirosis in Vietnam. Hand washing after farming/ gardening (OR 0.57, CI 0.38-0.86, p = 0.007) and bathing after farming, gardening, contact with cattle and poultry (OR 0.33, CI 0.19-0.58, p = 0.000) were determined as protective factors for this disease. CONCLUSIONS: In short, the case-control study has revealed the risks in agricultural and animal practices and protective behavioral factors related to human leptospirosis in Vietnam. The findings suggested promotion of communication and health education programs targeting health behaviors in daily life and agricultural practices. Using personal protective equipment such as gowns, gloves, and boots during agricultural practices, especially cultivating and animal farming, is most recommended.

A novel nested allele-specific PCR protocol for the detection of the HLA-A*33:03, a SCAR-associated allele, in Vietnamese people.

BACKGROUND: Severe cutaneous adverse drug reactions (SCARs) are rare but deadly drug reactions with severe damages to patients. One of the most well-known SCARs risk factors is the human leukocyte antigen (HLA) genes polymorphism. Among the HLA polymorphic alleles, the HLA-A*33:03 allele has been found in association with SCARs induced by various drugs, especially in Asian people. There has not been any report on the specific detection protocol of the HLA-A*33:03 allele. OBJECTIVE: This study aimed to design a nested AS-PCR protocol for detecting and distinguishing diplotype genotype of the HLA-A*33:03 allele. METHODS: A nested allele-specific (AS)-PCR protocol with four primer sets was designed. The method was compared with the Sanger sequencing method on 100 samples of unknown genotypes of unrelated Vietnamese people. RESULTS: The nested AS-PCR method could identify the HLA-A*33:03 allele and the HLA-A*33:03 diplotype genotypes. Comparison with the Sanger sequencing method showed an absolute agreement (κ = 1.00, p < 0.001). The nested ASPCR protocol had a sensitivity of 100% (95%CI: 92.13-100%) and a specificity of 100% (95%CI: 93.51-100%). The protocol was used for the determination of HLA-A*33:03 allele distribution in 810 unrelated Vietnamese Kinh people, showing a frequency of HLA-A*33:03 carriers of 19.6% and an allele frequency of 10.55%. CONCLUSIONS: A novel nested AS-PCR method with a hundred-percent sensitivity and a specificity for the HLA-A*33:03 allele detection was reported. The protocol can be applied for the stratification of patients at SCAR risks with various drugs.

Prevalence and Characterization of Gastroenteritis Viruses among Hospitalized Children during a Pilot Rotavirus Vaccine Introduction in Vietnam.

Rotavirus (RV), norovirus (NoV), sapovirus (SaV), and human astrovirus (HAstV) are the most common viral causes of gastroenteritis in children worldwide. From 2016 to 2021, we conducted a cross-sectional descriptive study to determine the prevalence of these viruses in hospitalized children under five years old in Nam Dinh and Thua Thien Hue provinces in Vietnam during the pilot introduction of the RV vaccine, Rotavin-M1 (POLYVAC, Hanoi, Vietnam). We randomly selected 2317/6718 (34%) acute diarrheal samples from children <5 years of age enrolled at seven sentinel hospitals from December 2016 to May 2021; this period included one year surveillance pre-vaccination from December 2016 to November 2017. An ELISA kit (Premier Rotaclone®, Meridian Bioscience, Inc., Cincinnati, OH, USA) was used to detect RV, and two multiplex real-time RT-PCR assays were used for the detection of NoV, SaV and HAstV. The prevalence of RV (single infection) was reduced from 41.6% to 22.7% (p < 0.0001) between pre- and post-vaccination periods, while the single NoV infection prevalence more than doubled from 8.8% to 21.8% (p < 0.0001). The SaV and HAstV prevalences slightly increased from 1.9% to 3.4% (p = 0.03) and 2.1% to 3.3% (p = 0.09), respectively, during the same period. Viral co-infections decreased from 7.2% to 6.0% (p = 0.24), mainly due to a reduction in RV infection. Among the genotypeable samples, NoV GII.4, SaV GI.1, and HAstV-1 were the dominant types, representing 57.3%, 32.1%, and 55.0% among the individual viral groups, respectively. As the prevalence of RV decreases following the national RV vaccine introduction in Vietnam, other viral pathogens account for a larger proportion of the remaining diarrhea burden and require continuing close monitoring.

Characteristics of human leptospirosis in three different geographical and climatic zones of Vietnam: a hospital-based study.

BACKGROUND: To our knowledge, this study is the first report on the seroprevalence of human leptospirosis and its epidemiological profile in 3 different geographical and climatic zones of Vietnam. METHODOLOGY: A hospital-based surveillance in 11 public hospitals in 3 provinces in Vietnam enrolled 3,815 patients with suspected leptospirosis. Two consecutive enzyme-linked immunosorbent assay IgM and a single microscopic aggregation test were applied at a 1:100 to 1:800 dilution for probable or confirmed cases. RESULTS: The findings showed that of the 3,815 suspected cases, 68 (1.8%) were Leptospira-confirmed and 248 (6.5%) probable cases, whereas more than a third were positive for acute ELISA-IgM sera. Furthermore, 20 different serovars were found, of which Wolffi (14.2%), Hebdomadis (13.8%), and Icterohaemorrhagiae (12.6%) were the most predominant. The ratio of probable and confirmed cases of leptospirosis between females and males was 1.4:1, and their clinical manifestation was not specific. Cases were more likely to be detected in groups that are farmers, pet raising or livestock farming, of working age, practicing either wading in mud or walking barefoot, or exposed to heavy rainfall. CONCLUSIONS: Analysis of human leptospirosis has indicated fairly high seroprevalence and diversity of Leptospira serovars circulating in all studied geographical zones in Vietnam. The findings suggest an imperative need for effective measures of disease prevention, especially in high-risk groups.

Genetic and biochemical analysis of PadR-padC promoter interactions during the phenolic acid stress response in Bacillus subtilis 168.

Bacillus subtilis 168 is resistant to phenolic acids by expression of an inducible enzyme, the phenolic acid decarboxylase (PadC), that decarboxylates these acids into less toxic vinyl derivatives. In the phenolic acid stress response (PASR), the repressor of padC, PadR, is inactivated by these acids. Inactivation of PadR is followed by a strong expression of padC. To elucidate the functional interaction between PadR and the padC promoter, we performed (i) footprinting assays to identify the region protected by PadR, (ii) electrophoretic mobility shift assays (EMSAs) with a modified padC promoter protected region to determine the interacting sequences, and (iii) random mutagenesis of padR to identify amino acid residues essential for the function of PadR. We identified an important consensus dyad sequence called IR1-2 (ATGT-8N-ACAT) overlapping a second dyad element (GTGT-8N-ACAT) that we named dIR1-2bis. The entire dIR1-2bis/IR1-2 sequence permits binding of two PadR dimers in EMSAs, which may be observed for bacteria grown under noninduced conditions where the padC promoter is completely repressed. Three groups of modified PadRs giving a PASR phenotype were characterized in vivo. The DNA sequences of certain mutant padR alleles indicate that important residues are all located in the region containing the coiled-coil leucine zipper domain that is involved in dimerization. These substitutions reduce the affinity of PadR binding to the padC promoter. Of particular interest are residue L128, located at the center of the putative coiled-coil leucine zipper domain, and residue E97, which is conserved among all PadRs.

A Novel Allele-Specific PCR Protocol for the Detection of the HLA-C*03:02 Allele, a Pharmacogenetic Marker, in Vietnamese Kinh People.

BACKGROUND: Allopurinol, a common anti-hyperuricemia drug, is well known as an inducer of severe cutaneous adverse drug reactions (SCARs). One of the most well-defined risk factors of allopurinol-induced SCARs is the presence of polymorphic alleles of human leukocyte antigen (HLA) genes, such as HLA-B*58:01 and HLA-C*03:02 alleles. There is no commercial test or published in-house protocol for the specific detection of the HLA-C*03:02 allele. In this article, we established for the first time a simple allele-specific (AS) PCR method to identify HLA-C*03:02 allele carriers, and at the same time, determine their zygosities. METHODS: A two-step AS-PCR protocol, using four primer sets, was designed to specifically amplify and differentiate the HLA-C*03:02 allele from 17 other HLA-C alleles found in Vietnamese people. The protocol was validated with PCR-sequencing-based typing (SBT) of 100 samples of unknown genotypes. RESULTS: The PCR protocol can detect the HLA-C*03:02 allele and determine the zygosity. The results of this protocol were highly consistent with those of the SBT (ĸ = 0.98, p < 0.001). Regarding the specific detection of the HLA-C*03:02 allele, the PCR protocol had a sensitivity of 100% (95% CI: 91.61-100%) and specificity of 98.3% (95% CI: 90.9-99.7%). The protocol was used to determine the distribution of the HLA-C*03:02 allele in 810 unrelated Vietnamese Kinh people, 14.2% of which were HLA-C*03:02 carriers, the allele frequency was 7.5%. CONCLUSION: A novel AS-PCR protocol with a sensitivity of 100% for the detection of the HLA-C*03:02 allele was established. The protocol can be used for personalized treatment with allopurinol in order to minimize the risk of SCARs in Vietnamese people as well as in other Asian populations with similar genetic characteristics.

Leptospira infection among human-close-contact animals in different geographical areas in Vietnam.

Leptospirosis is a neglected disease in Vietnam. Only a few studies have evaluated the status of Leptospira infection in both humans and animals. To our knowledge, this is the first serological survey of Leptospira in both domestic and wild animals, which may act as reservoirs of this agent. This study aimed to evaluate the seroprevalence of Leptospira in animals that are in close contact with humans in different geographical areas in Vietnam. Sera were collected from 1205 individual animals of six species, including buffaloes, cattle, cats, dogs, swine, and rats. The microscopic agglutination test (MAT) against 25 serovars of Leptospira spp. has been employed to detect serovars of Leptospira among the studied population. Overall, 44.2% of buffaloes, 24.9% of cattle, 10.2% of swine, 32.9% of dogs, 12.2% of cats, and 16% of rats were seropositive. A total of 17 different serovars were detected, of which serovars Hebdomadis and Canicola circulated in all the studied animal species. Variability of the predominant serovars circulating in animal species and in different geographical areas of Vietnam has been noted. We conclude that this study showed a high prevalence of Leptospira circulating in animals that are in close contact with humans, raising an alert of the important sources of pathogenic leptospires transmission to humans in Vietnam. These findings prove an imperative need for effective measures for disease prevention.

Inactivation of PadR, the repressor of the phenolic acid stress response, by molecular interaction with Usp1, a universal stress protein from Lactobacillus plantarum, in Escherichia coli.

The phenolic acid decarboxylase gene padA is involved in the phenolic acid stress response (PASR) in gram-positive bacteria. In Lactobacillus plantarum, the padR gene encodes the negative transcriptional regulator of padA and is cotranscribed with a downstream gene, usp1, which encodes a putative universal stress protein (USP), Usp1, of unknown function. The usp1 gene is overexpressed during the PASR. However, the role and the mechanism of action of the USPs are unknown in gram-positive bacteria. Therefore, to gain insights into the role of USPs in the PASR; (i) a usp1 deletion mutant was constructed; (ii) the two genes padR and usp1 were coexpressed with padA under its own promoter as a reporter gene in Escherichia coli; and (iii) molecular in vitro interactions between the PadR, Usp1, and the padA promoter were studied. Although the usp1 mutant strain retained phenolic acid-dependent PAD activity, it displayed a greater sensitivity to strong acidic conditions compared to that of the wild-type strain. PadR cannot be inactivated directly by phenolic acid in E. coli recombinant cultures but is inactivated by Usp1 when the two proteins are coexpressed in E. coli. The PadR inactivation observed in recombinant E. coli cells was supported by electrophoretic mobility shift assays. Although Usp1 seems not to be absolutely required for the PASR, its capacity to inactivate PadR indicates that it could serve as an important mediator in acid stress response mechanisms through its capacity to interact with transcriptional regulators.

Proteomics of proteins associated with astaxanthin accumulation in the green algae Haematococcus lacustris under the influence of sodium orthovanadate.

An extensive proteomics analysis has identified proteins associated with astaxanthin accumulation in the green algae Haematococcus lacustris under oxidative stress induced by sodium orthovanadate (SOV). Measurement of total carotenoid accumulation per cell biomass showed an increase from 81 to 136 pg/cell after being exposed to 2.5 mM SOV, when compared to the control cells at day 3 of cultivation. A total of 83 proteins were differentially expressed in SOV-treated H. lacustris in comparison with control cells. They consisted of 34 down-regulated and 49 up-regulated proteins. Of these, 17 highly-expressed proteins were analyzed by MALDI-TOF-MS to identify the function of the differentially expressed proteins in response to oxidative stress in H. lacustris.

Phenolic acid-mediated regulation of the padC gene, encoding the phenolic acid decarboxylase of Bacillus subtilis.

In Bacillus subtilis, several phenolic acids specifically induce expression of padC, encoding a phenolic acid decarboxylase that converts these antimicrobial compounds into vinyl derivatives. padC forms an operon with a putative coding sequence of unknown function, yveFG, and this coding sequence does not appear to be involved in the phenolic acid stress response (PASR). To identify putative regulators involved in the PASR, random transposon mutagenesis, combined with two different screens, was performed. PadR, a negative transcriptional regulator of padC expression, was identified. padR is not located in the vicinity of padC, and the expression of padR is low and appears constitutive. This is in contrast with what occurs in other gram-positive bacteria, in which padR is autoregulated and induced by phenolic acids. Further screening of the transposon library failed to identify genes other than padR involved in the PASR. Modest inactivation of padR by phenolic acids was obtained in recombinant Escherichia coli expressing padC and padR, and this translates into induction of decarboxylase activity. Gel shift promoter binding assays performed with and without MgCl(2), and with and without phenolic acids, demonstrated that phenolic acids were able to abolish the binding of PadR to the yveFG-padC promoter in the absence of MgCl(2). Altogether, our results indicate that (i) PadR is inactivated directly by phenolic acids in vitro, (ii) inhibition of PadR in response to phenolic acids may occur without the need for a sensor-like effector in B. subtilis, and (iii) phenolic acids are able to modulate PadR activity in E. coli in the absence of any additional effector.

Kinetics and intensity of the expression of genes involved in the stress response tightly induced by phenolic acids in Lactobacillus plantarum.

In Lactobacillus plantarum, PadR, the negative transcriptional regulator of padA encoding the phenolic acid decarboxylase, is divergently oriented from padA. Moreover, it forms an operonic structure with usp1, a genewhose products display homology with proteins belonging to the UspA family of universal stress proteins. PadR is inactivated by the addition of p-coumaric, ferulic or caffeic acid to the culture medium. In order to better characterize the stress response of this bacterium to phenolic acids, we report here the kinetics and quantitative expression by qRT-PCR of the 3 genes from the padA locus. The expression of the 3 genes is very low in the non-induced condition, while the addition of 1.2 mMp-coumaric acid induces an increase in the expression of padA, padR and usp1 by factors of 8,000, 37 and 13, respectively. These maximum relative transcript levels are obtained after 5 min of induction at the end of the exponential growth phase, while phenolic acid decarboxylase activity, not detectable before induction, is increased by a factor of 8,000 in 10 min. The apparent half-life of padA mRNA is about 1.4 min. The padA-padR system displays dynamic characteristics that are valuable to the development of tools for gene expression in this bacterium.

The proteome and transcriptome analysis of Bacillus subtilis in response to salicylic acid.

Phenolic acids that are present in plant-soil ecosystems can be considered as toxins which induce specific stress responses in microorganisms. In this paper, we have analyzed the global response of the soil bacterium Bacillus subtilis to salicylic acid using proteomics and transcriptomics. The results demonstrate that salicylic acid caused predominantly the induction of the SigmaB-dependent general stress response in B. subtilis which is not related to the acidic conditions. Treatment of B. subtilis with growth-inhibitory concentrations of 4 mM salicylic acid caused protein damage in B. subtilis as reflected by the induction of the CtsR and Spx regulons. Both phenolic acid decarboxylases (pads) of B. subtilis padC and bsdBCD (yclBCD) were induced by 4 mM salicylic acid that were previously shown to be involved in decarboxylation and detoxification of different phenolic acids. Deletion of the putative LysR-type regulator encoded by the divergently transcribed bsdA (yclA) gene upstream of the bsdBCD operon revealed that BsdA is the transcriptional activator of bsdBCD expression in response to salicylic acid. Phenotype analysis of bsdA and padC single and double mutants demonstrated that both pads confer resistance to salicylic acid in B. subtilis.

Cloning, deletion, and characterization of PadR, the transcriptional repressor of the phenolic acid decarboxylase-encoding padA gene of Lactobacillus plantarum.

Lactobacillus plantarum displays a substrate-inducible padA gene encoding a phenolic acid decarboxylase enzyme (PadA) that is considered a specific chemical stress response to the inducing substrate. The putative regulator of padA was located in the padA locus based on its 52% identity with PadR, the padA gene transcriptional regulator of Pediococcus pentosaceus (L. Barthelmebs, B. Lecomte, C. Diviès, and J.-F. Cavin, J. Bacteriol. 182:6724-6731, 2000). Deletion of the L. plantarum padR gene clearly demonstrates that the protein it encodes is the transcriptional repressor of divergently oriented padA. The padR gene is cotranscribed with a downstream open reading frame (ORF1), the product of which may belong to a group of universal stress proteins (Usp). The padR deletion mutant overexpressed padA constitutively, and the padA promoter appears to be tightly regulated in this bacterium. Gel mobility shift assays using the padA gene promoter region and purified PadR expressed in Escherichia coli indicated that operator DNA binding by PadR was not eliminated by addition of p-coumarate. Gel mobility shift assays using partially purified extracts of native PadR protein from both phenolic acid-induced and noninduced L. plantarum cells demonstrate that inactivation of PadR by phenolic acids requires the integrity of L. plantarum and mediation by a specific protein absent in E. coli.