Co-circulation of two Mumps virus genotypes in Assam, India.

Mumps is a vaccine-preventable disease, and research on the vaccine's efficacy has recently indicated declining efficacy that has failed to protect against primary infections or reinfections, leading to a global resurgence in nations that use mumps vaccine in their national immunization programmes (NIPs). Lack of reports on its infection, documentation and published studies prevents it from being recognized as a public health issue in India. The waning of immunity is ascribed to the changes between the circulating and vaccine strains. The goal of the current study was to describe the circulating MuV strains in the Dibrugarh district of Assam, India, from 2016 to 2019. Blood samples were examined for IgM antibodies, and throat swab samples were put through Taqman assay for molecular detection. The small hydrophobic (SH) gene was targeted for genotyping through sequencing, and its genetic variations and phylogenetic analysis were carried out. Mumps RNA was found in 42 cases, and Mumps IgM in 14, of which 60% (25/42) of the cases were male and 40% (17/42) were female mostly affecting children between the ages of 6 and 12. Sequence and phylogeny analyses of SH gene revealed Genotypes C (83%) and G (17%) were simultaneously circulating during the study period. The study offers crucial genetic baseline information for the creation of Mumps prevention and control measures. Therefore, based on the research, it is clear that developing an effective vaccination strategy should take into account all currently prevalent genotypes in order to provide better protection against the disease's comeback.

Genetic diversity of Plasmodium falciparum AMA-1 antigen from the Northeast Indian state of Tripura and comparison with global sequences: implications for vaccine development.

BACKGROUND: Malaria continues to be a major public health problem in the Northeastern part of India despite the implementation of vector control measures and changes in drug policies. To develop successful vaccines against malaria, it is important to assess the diversity of vaccine candidate antigens in field isolates. This study was done to assess the diversity of Plasmodium falciparum AMA-1 vaccine candidate antigen in a malaria-endemic region of Tripura in Northeast India and compare it with previously reported global isolates with a view to assess the feasibility of developing a universal vaccine based on this antigen. METHODS: Patients with fever and malaria-like illness were screened for malaria and P. falciparum positive cases were recruited for the current study. The diversity of PfAMA-1 vaccine candidate antigen was evaluated by nested PCR and RFLP. A selected number of samples were sequenced using the Sanger technique. RESULTS: Among 56 P. falciparum positive isolates, Pfama-1 was successfully amplified in 75% (n = 42) isolates. Allele frequencies of PfAMA-1 antigen were 16.6% (n = 7) for 3D7 allele and 33.3% (n = 14) in both K1 and HB3 alleles. DNA sequencing revealed 13 haplotypes in the Pfama-1 gene including three unique haplotypes not reported earlier. No unique amino-acid substitutions were found. Global analysis with 2761 sequences revealed 435 haplotypes with a very complex network composition and few clusters. Nucleotide diversity for Tripura (0.02582 ± 0.00160) showed concordance with South-East Asian isolates while recombination parameter (Rm = 8) was lower than previous reports from India. Population genetic structure showed moderate differentiation. CONCLUSIONS: Besides documenting all previously reported allelic forms of the vaccine candidate PfAMA-1 antigen of P. falciparum, new haplotypes not reported earlier, were found in Tripura. Neutrality tests indicate that the Pfama-1 population in Tripura is under balancing selection. This is consistent with global patterns. However, the high haplotype diversity observed in the global Pfama-1 network analysis indicates that designing a universal vaccine based on this antigen may be difficult. This information adds to the existing database of genetic diversity of field isolates of P. falciparum and may be helpful in the development of more effective vaccines against the parasite.

Pre-therapeutic Biomarkers for Ranibizumab Therapy among Type 2 Diabetic Patients with Diabetic Macular Edema.

SIGNIFICANCE: A differential outcome in randomized controlled trials of anti-vascular endothelial growth factor (anti-VEGF) therapy, including ranibizumab, for diabetic macular edema is a major dilemma for planning, optimizing, and managing clinical usage. The variable outcome of the therapeutics necessitates the importance of finding a predictive biomarker for anti-VEGF therapy to improve subject selection. PURPOSE: Our study correlates the baseline pro- and anti-VEGF isoforms and its three receptors (VEGFReceptor1, VEGFReceptor2, and VEGFReceptor3) for circulatory candidate protein molecules among diabetic patients with macular edema, with the clinical outcome of ranibizumab therapy. METHODS: This study included 86 individuals who were anti-VEGF naive at the time of ascertainment but have completed the standardized therapy regimen of the clinic. Plasma proteins for pro- and anti-VEGF isoforms and its three receptors were determined in replicate by an enzyme-linked immunosorbent assay. RESULTS: The study demonstrated that 56 (65.12%) individuals benefited from the therapy in terms of letter gain (Snellen chart). Baseline plasma soluble VEGF receptor 2 (sVEGFR-2) was significantly higher among responders (65.10 pg/mL; 95% confidence interval, 55.41 to 74.80 pg/mL) compared with nonresponders (46.38 pg/mL; 95% confidence interval, 38.69 to 54.07 pg/mL; PFDR = .03). Diffuse diabetic macular edema with proliferative diabetic retinopathy increases the risk of nonresponse to the therapy by 3.03-fold (PFDR = .04). CONCLUSIONS: The present study postulates that diffuse diabetic macular edema with proliferative diabetic retinopathy and baseline circulatory soluble VEGF receptor 2 may be potential candidates as therapy-stratifying markers for ranibizumab treatment among patients with diabetic macular edema.

Distribution pattern of amino acid mutations in chloroquine and antifolate drug resistance associated genes in complicated and uncomplicated Plasmodium vivax isolates from Chandigarh, North India.

BACKGROUND: The increasing antimalarial drug resistance is a significant hindrance to malaria control and elimination programs. For the last six decades, chloroquine (CQ) plus pyrimethamine remains the first-line treatment for P. vivax malaria. Regions where both P. falciparum and P. vivax co-exist, P. vivax is exposed to antifolate drugs due to either misdiagnosis or improper treatment that causes selective drug pressure to evolve. Therefore, the present study aims to estimate antimalarial drug resistance among the complicated and uncomplicated P. vivax patients. METHODS: A total of 143 P. vivax malaria positive patients were enrolled in this study, and DNA was isolated from their blood samples. Pvcrt-o, Pvmdr-1, Pvdhps, and Pvdhfr genes were PCRs amplified, and drug resistance-associated gene mutations were analyzed. Statistical analysis of the drug resistance genes and population diversity was performed using MEGA vs. 7.0.21 and DnaSP v software. RESULTS: Among the CQ resistance marker gene Pvcrt-o, the prevalence of K10 insertion was 17.5% (7/40) and 9.5% (7/73) of complicated and uncomplicated P vivax group isolates respectively. In Pvmdr-1, double mutant haplotype (M958/L1076) was found in 99% of the clinical isolates. Among the pyrimethamine resistance-associated gene Pvdhfr, the double mutant haplotype I13P33F57R58T61N117I173 was detected in 23% (11/48) in complicated and 20% (17/85) in uncomplicated group isolates. In the sulphadoxine resistance-associated Pvdhps gene, limited polymorphism was observed with the presence of a single mutant (D459A) among 16 and 5% of the clinical isolates in the complicated and uncomplicated group respectively. CONCLUSION: The study presents the situations of polymorphism in the antimalarial drug resistance-associated genes and emphasizes the need for regular surveillance. It is imperative for the development of suitable antimalarial drug policy in India.

Decreased In Vitro Artemisinin Sensitivity of Plasmodium falciparum across India.

Artemisinin-based combination therapy (ACT) has been used to treat uncomplicated Plasmodium falciparum infections in India since 2004. Since 2008, a decrease in artemisinin effectiveness has been seen throughout the Greater Mekong Subregion. The geographic proximity and ecological similarities of northeastern India to Southeast Asia may differentially affect the long-term management and sustainability of ACT in India. In order to collect baseline data on variations in ACT sensitivity in Indian parasites, 12 P. falciparum isolates from northeast India and 10 isolates from southwest India were studied in vitro Ring-stage survival assay (RSA) showed reduced sensitivity to dihydroartemisinin in 50% of the samples collected in northeast India in 2014 and 2015. Two of the 10 assayed samples from the southwest region of India from as far back as 2012 also showed decreased sensitivity to artemisinin. In both these regions, kelch gene sequences were not predictive of reduced artemisinin sensitivity, as measured by RSA. The present data justify future investments in integrated approaches involving clinical follow-up studies, in vitro survival assays, and molecular markers for tracking potential changes in the effectiveness of artemisinin against P. falciparum throughout India.

Exploration of genetic diversity of Plasmodium vivax circumsporozoite protein (Pvcsp) and Plasmodium vivax sexual stage antigen (Pvs25) among North Indian isolates.

BACKGROUND: Malaria is one of the important vector-borne diseases with high fatality rates in tropical countries. The pattern of emergence and spread of novel antigenic variants, leading to escape of vaccine-induced immunity might be factors responsible for severe malaria. A high level of polymorphism has been reported among malarial antigens which are under selection pressure imposed by host immunity. There are limited reports available on comparative stage-specific genetic diversity among Plasmodium vivax candidate genes in complicated vivax malaria. The present study was planned to study genetic diversity (Pvcsp and Pvs25) among complicated and uncomplicated P. vivax isolates. METHODS: Pvcsp and Pvs2-specific PCRs and DNA sequencing were performed on P. vivax PCR positive samples. Genetic diversity was analysed using appropriate software. RESULTS: The present study was carried out on 143 P. vivax clinical isolates, collected from Postgraduate Institute of Medical Education and Research, Chandigarh. Among the classic and variant types of Pvcsp, the VK210 (99%; 115/116) was found to be predominant in both complicated and uncomplicated group isolates. Out of the various peptide repeat motifs (PRMs) observed, GDRADGQPA (PRM1) and GDRAAGQPA (PRM2) was the most widely distributed among the P. vivax isolates. Whereas among the Pvs25 isolates, 100% of double mutants (E97Q/I130T) in both the complicated (45/45) as well as in the uncomplicated (81/81) group was observed. CONCLUSION: An analysis of genetic variability enables an understanding of the role of genetic variants in severe vivax malaria.

Long telomeres cooperate with p53, MDM2, and p21 polymorphisms to raise pediatric solid tumor risk.

BACKGROUND: While leukocyte telomere length has been linked with altered risk in adult cancer, limited information is available on its association with risk in pediatric solid tumors. We investigated the association of telomeric alterations with risk of pediatric solid tumors. We also investigated whether altered telomeres cooperated with the TP53 rs1042522, MDM2 rs2279744 and CDKN1A (p21cip1 ) rs1059234 single-nucleotide polymorphisms to modify cancer risk. METHODS: A total of 101 tumor patients and 202 controls were recruited for this age- and gender-matched case-control study. Relative telomere length (RTL) was determined in peripheral blood leukocytes using quantitative real-time polymerase chain reaction (PCR), and the polymorphisms were genotyped using PCR-restriction fragment length polymorphism. RESULTS: Using median RTL in the healthy controls as a cut-off, children with longer telomeres were at an increased risk of developing a solid tumor (OR, 2.70; P < 0.01). When participants were categorized according to control RTL quartiles, a significant dose-response relationship was observed (χ2  = 10.95; P < 0.001). The risk for tumors increased nearly threefold (P = 0.001) for the triple interaction RTL × TP53 rs1042522 × p21cip1 rs1059234 compared with the maximum effect of any single factor, although the interaction effect was less than additive. The MDM2 rs2279744 GG genotype reduced pediatric solid tumor risk significantly (OR, 0.51). CONCLUSION: Combined analysis of telomeres and genetic polymorphisms in the TP53 pathway can provide important clues to understanding pediatric solid tumor etiology.

Exposure to Plasmodium vivax is associated with the increased expression of exhaustion markers on γδ T lymphocytes.

Gamma delta (γδ) T cells exhibit potent anti-Plasmodium activity but are also implicated in the immunopathology of malaria. It is currently poorly understood how γδ T cells are affected in human suffering from Plasmodium vivax infection or in symptomless individuals living in an endemic region. We examined both the percentages and expression of markers associated with immune exhaustion in γδ T cells in individuals living in a P. vivax endemic region by flow cytometry. The percentage of γδ T cells in the blood was significantly higher both in acute P. vivax-positive patients and in individuals from an endemic region in comparison with control uninfected adults. The frequency of the expression of the exhaustion markers-Tim-3, Lag-3, CTLA-4 and PD-1 was higher in γδ and total T cells from P. vivax-infected patients than in those populations from control uninfected adults. Individuals from a P. vivax endemic region showed elevated percentages of Tim-3-, Lag-3- and CTLA-4-positive γδ T cells and an increased percentage of Tim-3-positive total T cells. The phenotypic exhaustion of these cells might be a protective mechanism preventing the immunopathology associated with activated T cells and may provide a rationale for targeted manipulation of this process in diseases such as malaria.

Salt-sensitive phenotypes: A community-based exploratory study from northeastern India.

Background: Salt sensitivity is known to increase the risk of cardiovascular diseases in both normotensive and hypertensive subjects. The population in the northeastern region of India consumes excess dietary salt but their saltsensitive phenotype is not known. Methods: We did a community-based exploratory study using volunteers in the northeastern region of India to determine salt-sensitive (SS) and salt-resistant (SR) phenotypes. A total of 374 (206 normotensive and 168 hypertensive) subjects who gave informed consent were stabilized for salt with 7 days of a low-salt (2.9 g/day) diet followed by 7 days of a high-salt (15.2 g/day) diet. SS was defined as an increase of mean arterial blood pressure ≥9 mmHg after a high-salt diet. Results: We noted an increase in systolic blood pressure of 9.3 mmHg in normotensive subjects and 10.7 mmHg in hypertensive subjects, with a modest effect on diastolic blood pressure (6.9 mmHg in normotensive and 8.2 mmHg in hypertensive subjects) after a high-salt diet. Salt-sensitive phenotype was present in 40.8% of normotensive and 47.6% of hypertensive subjects. Resistance to introduction of high salt was observed in 43.7% of normotensive and 33.9% of hypertensive subjects. Consumption of extra salt (adjusted OR 1.99, 95% CI 1.25-3.18) was independently associated with salt sensitivity. Conclusion: Salt sensitivity was found in a large proportion of normotensive and hypertensive subjects. Restriction of salt intake could be an effective intervention to control hypertension among salt-sensitive subjects.

Renin-Angiotensin System Gene Polymorphisms and Hypertension.

Hypertension has emerged as a major public health problem in developing countries including India. Hypertension, a major cardiovascular risk factor is recognized as a multi-factorial trait resulting from the interaction of various environmental and genetic factors. The genetic contribution is speculated to make 30% to 40% of the variation in blood pressure. Identification of variant genes that contribute to the development of hypertension is further complicated because the cardiac output and peripheral resistance, are controlled by other intermediary phenotypes. Sodium has been postulated as the major intermediary in blood pressure regulation. Therefore, polymorphisms of candidate genes encoding proteins influencing renal tubular sodium transport, either directly or indirectly through effects on intra-renal hemodynamics, have been associated with differences in blood pressure level. Considering the importance of genetics on hypertension and the diversity of the related genes, evaluation of these genes and the study of new genes are necessary. It is hoped that by deducting related genes for essential hypertension in individual, will help in prevention of potential patients. We will be able to diagnose those at risk and develop new treatments for these patients.

Pro- and antiangiogenic VEGF and its receptor status for the severity of diabetic retinopathy.

PURPOSE: Alteration of pro- and antiangiogenic homeostasis of vascular endothelial growth factor (VEGF) isoforms in patients with hyperglycemia seems crucial but substantially unexplored at least quantitatively for diabetic retinopathy (DR). Therefore, in the present study we aimed to estimate the difference between the pro- (VEGF165a) and antiangiogenic (VEGF165b) VEGF isoforms and its soluble receptors for severity of DR. METHODS: The study included 123 participants (diabetic retinopathy: 81, diabetic control: 20, non-diabetic control: 22) from the Regional Institute of Ophthalmology, Kolkata. The protein levels of VEGF165a (proangiogenic), VEGF165b (antiangiogenic), VEGF receptor 1 (VEGFR1), VEGFR2, and VEGFR3 in plasma were determined with enzyme-linked immunosorbent assay (ELISA). RESULTS: An imbalance in VEGF homeostasis, a statistically significant concomitant increase (p<0.0001) in the level of VEGF165a and a decrease in the level of VEGF165b, was observed with the severity of the disease. Increased differences between VEGF165a and VEGF165b i.e. VEGF165a-b concomitantly increased statistically significantly with the severity of the disease (p<0.0001), patients with diffuse diabetic macular edema (DME) with proliferative DR (PDR) had the highest imbalance. The plasma soluble form of VEGFR2 concentration consistently increased statistically significantly with the severity of the disease (p<0.0001). CONCLUSIONS: The increased difference or imbalance between the pro- (VEGF165a) and antiangiogenic (VEGF165b) homeostasis of the VEGF isoforms, seems crucial for an adverse prognosis of DR and may be a better explanatory marker compared with either VEGF isoform.

p16 gene silencing along with p53 single-nucleotide polymorphism and risk of esophageal cancer in Northeast India.

The high incidence of esophageal cancer in Northeast India and the unique ethnic background and dietary habits provide a great opportunity to study the molecular genetics behind esophageal squamous cell carcinoma in this part of the region. We hypothesized that in addition to currently known environmental risk factors for esophageal cancer, genetic and epigenetic factors are also involved in esophageal carcinogenesis in Northeast India. Therefore, in this study, we explored the possible association between the two important G1 cell cycle regulatory genes p16 and p53 and environmental risk factors and risk of esophageal carcinogenesis. A total of 100 newly diagnosed esophageal cancer cases along with equal number of age-, sex-, and ethnicity-matched controls were included in this study. Methylation-specific polymerase chain reaction was used to determine the p16 promoter methylation status. Single-nucleotide polymorphism at codon 72 of p53 gene was assessed by the polymerase chain reaction-restriction fragment length polymorphism method. Aberrant methylation of p16 gene was seen in 81% of esophageal cancer cases. Hypermethylation of p16 gene was not found in healthy controls. p53 Pro/Pro genotype was found to be a risk genotype in Northeast India compared with Arg/Pro and Arg/Arg. p53 variant/polymorphism was significantly associated with esophageal cancer risk in the study population under all three genetic models, namely, dominant model (Arg/Pro + Pro/Pro vs Arg/Arg odds ratio = 2.25, confidence interval = 1.19-4.26; p = 0.012), recessive model (Arg/Arg + Arg/Pro vs Pro/Pro odds ratio = 2.35, confidence interval = 1.24-4.44; p = 0.008), and homozygous model (Pro/Pro vs Arg/Arg odds ratio = 3.33, confidence interval = 1.54-7.20; p = 0.002). However, p53 variant/polymorphism was not statistically associated with esophageal cancer risk under the heterozygous model (Pro/Pro vs Arg/Pro). In the case-only analysis based on p16 methylation, the p53 variant/polymorphism (Pro/Pro or Arg/Pro) showed significant association for esophageal cancer risk (odds ratio = 3.33, confidence interval = 1.54-7.20; p = 0.002). Gene-gene and gene-environment interaction using the case-only approach revealed a strong association between p16 methylation, p53 single-nucleotide polymorphism, and environmental factors and esophageal cancer risk. Cases with p16 methylation and p53 variant/polymorphism (Pro/Pro or Arg/Pro) along with both betel quid and tobacco chewing habit (odds ratio = 8.29, confidence interval = 1.14-60.23; p = 0.037) conferred eightfold increased risk toward esophageal cancer development. This study reveals a synergistic interaction between epigenetic, genetic, and environmental factors and risk of esophageal cancer in this high-incidence region of Northeast India. The inactivation of either p16 or p53 in a majority of esophageal cancer cases in this study suggests the possible crosstalk between the important cell cycle genes.

Genetic diversity of Plasmodium falciparum merozoite surface protein-1 (block 2), glutamate-rich protein and sexual stage antigen Pfs25 from Chandigarh, North India.

OBJECTIVE: To elucidate the genetic diversity of Plasmodium falciparum in residual transmission foci of northern India. METHODS: Clinically suspected patients with malaria were screened for malaria infection by microscopy. 48 P. falciparum-infected patients were enrolled from tertiary care hospital in Chandigarh, India. Blood samples were collected from enrolled patients, genomic DNA extraction and nested PCR was performed for further species confirmation. Sanger sequencing was carried out using block 2 region of msp1, R2 region of glurp and pfs25-specific primers. RESULTS: Extensive diversity was found in msp1 alleles with predominantly RO33 alleles. Overall allelic prevalence was 55.8% for RO33, 39.5% for MAD20 and 4.7% for K1. Six variants were observed in MAD20, whereas no variant was found in RO33 and K1 alleles. A phylogenetic analysis of RO33 alleles indicated more similarity to South African isolates, whereas MAD20 alleles showed similarity with South-East Asian isolates. In glurp, extensive variation was observed with eleven different alleles based on the AAU repeats. However, pfs25 showed less diversity and was the most stable among the targeted genes. CONCLUSION: Our findings document the genetic diversity among circulating strains of P. falciparum in an area of India with low malaria transmission and could have implications for control strategies to reach the national goal of malaria elimination.

Molecular characterization of Plasmodium falciparum in Arunachal Pradesh from Northeast India based on merozoite surface protein 1 & glutamate-rich protein.

BACKGROUND & OBJECTIVES: Northeast (NE) India is one of the high endemic regions for malaria with a preponderance of Plasmodium falciparum, resulting in high morbidity and mortality. The P. falciparum parasite of this region showed high polymorphism in drug-resistant molecular biomarkers. However, there is a paucity of information related to merozoite surface protein 1 (msp-1) and glutamate-rich protein (glurp) which have been extensively studied in various parts of the world. The present study was, therefore, aimed at investigating the genetic diversity of P. falciparum based on msp-1 and glurp in Arunachal Pradesh, a State in NE India. METHODS: Two hundred and forty nine patients with fever were screened for malaria, of whom 75 were positive for P. falciparum. Blood samples were collected from each microscopically confirmed patient. The DNA was extracted; nested polymerase chain reaction and sequencing were performed to study the genetic diversity of msp-1 (block 2) and glurp. RESULTS: The block 2 of msp-1 gene was found to be highly polymorphic, and overall allelic distribution showed that RO33 was the dominant allele (63%), followed by MAD20 (29%) and K1 (8%) alleles. However, an extensive diversity (9 alleles and 4 genotypes) and 6-10 repeat regions exclusively of R2 type were observed in glurp. INTERPRETATION & CONCLUSIONS: The P. falciparum population of NE India was diverse which might be responsible for higher plasticity leading to the survival of the parasite and in turn to the higher endemicity of falciparum malaria of this region.

An analysis of respondent-driven sampling with injecting drug users in a high HIV prevalent state of India.

BACKGROUND: Personal networks are significant social spaces to spread of HIV or other blood-borne infections among hard-to-reach population, viz., injecting drug users, female sex workers, etc. Sharing of infected needles or syringes among drug users is one of the major routes of HIV transmission in Manipur, a high HIV prevalence state in India. This study was carried out to describe the network characteristics and recruitment patterns of injecting drug users and to assess the association of personal network with injecting risky behaviors in Manipur. METHODS: A total of 821 injecting drug users were recruited into the study using respondent-driven sampling (RDS) from Bishnupur and Churachandpur districts of Manipur; data on demographic characteristics, HIV risk behaviors, and network size were collected from them. Transition probability matrices and homophily indices were used to describe the network characteristics, and recruitment patterns of injecting drug users. Univariate and multivariate binary logistic regression models were performed to analyze the association between the personal networks and sharing of needles or syringes. RESULTS: The average network size was similar in both the districts. Recruitment analysis indicates injecting drug users were mostly engaged in mixed age group setting for injecting practice. Ever married and new injectors showed lack of in-group ties. Younger injecting drug users had mainly recruited older injecting drug users from their personal network. In logistic regression analysis, higher personal network was found to be significantly associated with increased likelihood of injecting risky behaviors. CONCLUSION: Because of mixed personal network of new injectors and higher network density associated with HIV exposure, older injecting drug users may act as a link for HIV transmission or other blood-borne infections to new injectors and also to their sexual partners. The information from this study may be useful to understanding the network pattern of injecting drug users for enriching the HIV prevention in this region.

Dimension and Socio-demographic Correlates of Domestic Violence: A study from Northeast India.

Present study was aimed to find out dimension and socio-demographic correlates of domestic violence in Assam, Sikkim and Meghalaya, Northeast India. Two districts from each state were selected at random and women aged 18-35 years from rural and urban localities were interviewed to obtain relevant information. The study included a total of 2249 participants (Rural = 1577 and Urban = 672) from Assam (650), Sikkim (1148) and Meghalaya (451). Domestic violence was recorded in 26.4% of study participants and highest in Meghalaya. Of all types, psychological violence was predominant. A number of socio-demographic factors have been identified as independent predictors for domestic violence in pooled and state specific analysis. Findings of our study may help in formulating strategies to prevent domestic violence.

Association of toll-like receptor 2 ∆22 and risk for gastric cancer considering main effects and interactions with smoking: a matched case-control study from Mizoram, India.

Toll-like receptors (TLRs) are evolutionary conserved cell surface receptors of the innate immune system. Smoking has significant immunological effects which are mediated via TLRs on various receptor-mediated innate response pathways. Polymorphisms of TLR genes are associated with susceptibility toward various malignancies. The present study was undertaken to examine the association between TLR2 ∆22 and gastric cancer. In this study, we also investigated the interaction between TLR2 ∆22 and smoking. A total of 133 histologically confirmed gastric cancer cases and 266 age-sex-matched controls were selected for this study. TLR2 ∆22 genotypes were determined by allele-specific polymerase chain reaction (PCR). Binary conditional logistic regression analysis was used to find the association of TLR2 ∆22 with risk of gastric cancer. Logistic regression using hierarchically well-formulated models was used for interaction analysis between smoking and TLR2 ∆22. Persons having TLR2 ∆22 heterozygous genotype had two times increased risk of gastric cancer in multivariate logistic regression model. The interaction analysis using hierarchical logistic regression models between smoking and TLR2 ∆22 by calculating separate X (2) for interaction model and only main effect model, the difference of X (2) 57.68-47.70 = 9.98 and degrees of freedom (df) 5-3 = 2, revealed significant (α = 0.05, df = 2) omnibus interaction. Our present study revealed TLR2 ∆22 to be significantly and independently associated with gastric cancer risk in Mizoram, and there is also evidence of significant interaction between smoking and TLR2 ∆22 with risk of gastric cancer.

In vitro adaptation of Plasmodium falciparum reveal variations in cultivability.

BACKGROUND: Culture-adapted Plasmodium falciparum parasites can offer deeper understanding of geographic variations in drug resistance, pathogenesis and immune evasion. To help ground population-based calculations and inferences from culture-adapted parasites, the complete range of parasites from a study area must be well represented in any collection. To this end, standardized adaptation methods and determinants of successful in vitro adaption were sought. METHODS: Venous blood was collected from 33 P. falciparum-infected individuals at Goa Medical College and Hospital (Bambolim, Goa, India). Culture variables such as whole blood versus washed blood, heat-inactivated plasma versus Albumax, and different starting haematocrit levels were tested on fresh blood samples from patients. In vitro adaptation was considered successful when two four-fold or greater increases in parasitaemia were observed within, at most, 33 days of attempted culture. Subsequently, parasites from the same patients, which were originally cryopreserved following blood draw, were retested for adaptability for 45 days using identical host red blood cells (RBCs) and culture media. RESULTS: At a new endemic area research site, ~65% of tested patient samples, with varied patient history and clinical presentation, were successfully culture-adapted immediately after blood collection. Cultures set up at 1% haematocrit and 0.5% Albumax adapted most rapidly, but no single test condition was uniformly fatal to culture adaptation. Success was not limited by low patient parasitaemia nor by patient age. Some parasites emerged even after significant delays in sample processing and even after initiation of treatment with anti-malarials. When 'day 0' cryopreserved samples were retested in parallel many months later using identical host RBCs and media, speed to adaptation appeared to be an intrinsic property of the parasites collected from individual patients. CONCLUSIONS: Culture adaptation of P. falciparum in a field setting is formally shown to be robust. Parasites were found to have intrinsic variations in adaptability to culture conditions, with some lines requiring longer attempt periods for successful adaptation. Quantitative approaches described here can help describe phenotypic diversity of field parasite collections with precision. This is expected to improve population-based extrapolations of findings from field-derived fresh culture-adapted parasites to broader questions of public health importance.

High burden of hepatitis C & HIV co-infection among people who inject drugs in Manipur, Northeast India.

BACKGROUND & OBJECTIVES: It is well documented that the Northeast state of Manipur in India has been dealing with the dual problems of injecting drug use and HIV for the last two decades, but the hepatitis C problem has not been so well characterized. The aim of this study was to assess the prevalence of hepatitis C virus (HCV) infection and HCV/HIV co-infection among people who inject drugs (PWID) in Manipur, and identify factors associated with infection. METHODS: Data were obtained from the Integrated Behavioural and Biological Assessment (2009-2010), a cross-sectional survey among 821 male PWID in two districts of Manipur (Churachandpur and Bishnupur). Information about drug use, sexual and injecting risk behaviours, and exposure to interventions was obtained, and biological specimens tested for HIV and HCV. Logistic regression analyses identified factors associated with HCV infection and HCV/HIV co-infection. RESULTS: HCV prevalence was 74 per cent (91% Churachandpur, 56% Bishnupur), and HCV/HIV co-infection was 29 per cent (38% Churachandpur, 21% Bishnupur). Among the 31 per cent of HIV positive PWID, 95 per cent were co-infected. HCV infection was associated with district, longer duration of injecting, injecting at least once daily, generally injecting with a used needle and syringe, and having had an HIV test. HCV/HIV co-infection was associated with district, older age, being employed, being widowed/divorced, longer duration of injecting, and feeling at risk of HIV infection. INTERPRETATION & CONCLUSIONS: The HCV/HIV co-infection among PWID in Manipur was very high, highlighting the urgent need for effective prevention, diagnosis and treatment.

Immunogenicity & safety of a single dose of live-attenuated Japanese encephalitis vaccine SA 14-14-2 in adults.

BACKGROUND & OBJECTIVES: Japanese encephalitis (JE) caused by mosquito-borne Flavivirus is one of the leading causes of viral encephalitis in Asia. Control strategies include vector control and human vaccination. Due to lack of immunization programmes in endemic regions, there are still high mortality and morbidity. A live-attenuated SA 14-14-2 JE vaccine (LAJEV) has been licensed and used in Asian countries, including India. We report the assessment of immunogenicity and safety of the vaccine in adults during the first mass adult vaccination campaign carried out in Assam, India. METHODS: One thousand and seventy five adults (aged ≥15 yr) who received LAJEV were monitored for adverse events following immunization for one year. The safety assessment of vaccinated population was evaluated till 28 days and at 6 and 12 months. Blood samples collected from the enrolled participants were tested by plaque reduction neutralization test (PRNT 50 ) to assess the neutralizing antibody titres (NATs) before vaccination and 28 days, six and 12 months post-vaccination (PV). RESULTS: Among the 1075 vaccinated individuals, four reported minor adverse effects from 30 min to 28 days PV. Based on the pre-vaccination NAT, the study participants were categorized as seronegative, moderately seropositive and strongly seropositive. Nearly 85.5 per cent of JE seronegative participants seroconverted by 28 days PV. The geometric mean titre (GMT) in all the three groups increased by 28 days and decreased by six and 12 months PV. Nearly 60 per cent of the moderately positive individuals exhibited four-fold rise in GMT, 28 days PV. Almost 95.5 per cent of the participants in the study population remained seroprotected at the end of 12 months PV. INTERPRETATION & CONCLUSIONS: This study on immunogenicity and safety of LAJEV in adults showed that a single dose of the live-attenuated vaccine was safe and induced protective immunity to both JE seronegative and naturally seropositive adults. Further study is required to find out long term protective efficacy of this vaccine.