Biswajyoti Borkakoty

Strongyloidiasis in Assam, India: A community-based study

Background: Strongyloidiasis is endemic in many tropical and subtropical countries and reports from northeast India are very few. Aim: A community-based study was carried out in Assam, India, to find out the occurrence of Strongyloides stercoralis. Materials and Methods: Stool samples were obtained from 198 randomly selected individuals from the community. Samples were processed using direct microscopy with formal-ether concentration methods. Results and Conclusion: Seventeen numbers of samples showed the presence of Strongyloides stercoralis (8.5%). A total of 105 (53%) individuals were positive for at least one intestinal parasite. The other intestinal parasites detected were Ascaris lumbricoides (33.3%), Trichuris trichiura (9.1%), hookworm (7.1%), Enterobius vermicularis (1.5%), and Giardia cyst (1.5%). Five out of 17 individuals positive for S.stercoralis had associated gastrointestinal, respiratory, and/or cutaneous symptoms.The present study although not exhaustive for true prevalence calls for attention in the backdrop of high malnutrition and pulmonary tuberculosis.

Expression of SPARC like protein 1 (SPARCL1), extracellular matrix-associated protein is down regulated in gastric adenocarcinoma

BACKGROUND SPARC-like protein 1 (SPARCL1/Hevin), a member of the SPARC family is defined by the presence of a highly acidic domain-I, a follistatin-like domain, and an extracellular calcium (EC) binding domain. SPARCL1 has been shown to be down-regulated in many types of cancer and may serve as a negative regulator of cell growth and proliferation. METHODS Both tumor and adjacent normal tissue were collected from patients with gastric adenocarcinoma. Monoclonal antibody developed against recombinant SPARCL1 was used to analyze the expression of SPARCL1 by immunohisto chemical and western blotting (WB) analysis. RESULTS The expression of SPARCL1 was found to be significantly lower or negligible in gastric adenocarcinoma tissues in nearly all of the cases in comparison with adjacent normal tissue. This comparison was found to be independent of the patients age, sex, and stage of cancer. CONCLUSIONS We postulate that down regulation of SPARCL1 may be related to inactivation of its tumor suppressor functions and might play an important role in the development of gastric adenocarcinoma.

Activation and Exhaustion of Adaptive Immune Cells in Hepatitis B Infection

In hepatitis B virus (HBV) infection, the immune reaction is responsible for viral clearance and preventing their spread within the host. However, the immune system is dysfunctional in patients with chronic HBV infection, leading to an inadequate immune response against the virus. A major factor contributing to inefficient immune function is the phenomenon of immune exhaustion. Hence, understanding immune activation and exhaustion during HBV infection is important, as it would provide insight in developing immunotherapy to control chronic HBV infection. The aim of this review is to highlight the existing information on immune effector functions and immune exhaustion in response to HBV infection.

An appraisal of clinicopathological parameters in Japanese encephalitis and changing epidemiological trends in upper Assam, India

CONTEXT Japanese encephalitis (JE), an acute mosquito-borne viral disease, is one of the leading causes of viral encephalitis in the South-East Asian region. JE is endemic in Assam. The morbidity and mortality due to JE is significant with outbreaks every year during the monsoons. AIMS The aim was to study the clinicopathological profile of JE; to examine their role in predicting disease outcome; and to document the increase in the incidence of JE among the adult population in this region. MATERIALS AND METHODS Clinically suspected acute encephalitis syndrome (AES) cases admitted in Assam Medical College and Hospital during the period of May 2011 to April 2012 were tested by JE virus specific Immunoglobulin M capture ELISA. STATISTICAL ANALYSIS USED Data analysis was performed using SPSS version 16.0. RESULTS Out of 424 AES cases, 194 were JE positive. The occurrence of JE in adults was higher (P < 0.001) than the pediatric age group. The study recorded a high rate of renal dysfunction in JE cases. A single case of JE induced abortion and two cases of JE-neurocysticercosis co-infections were documented. Regression analysis revealed that adult population, unconsciousness, paresis and elevated cerebrospinal fluid protein level were associated with a worse prognosis in JE cases. Mortality in JE positive cases was higher than the JE negative cases (P = 0.001). CONCLUSION The study attempts to highlight the role played by a combination of clinical and laboratory parameters in assessing the severity and outcome in JE and may help in directing the limited medical resources toward those that need it the most.

Seroprevalence of Scrub Typhus Infection in Arunachal Pradesh, India

INTRODUCTION Scrub typhus is a major reason for febrile illness, caused by a bacterium Orientia tsutsugamushi, a rickettsial pathogen. Few outbreaks of scrub typhus have been reported from Arunachal Pradesh in recent past. However, there is lack of seroprevalence data from the region. In this regard, this study was undertaken using archival serum sample available from seven districts of Arunachal Pradesh. METHODOLOGY This serological study was conducted in Regional Medical Research Center for NE Region, Dibrugarh. Reactivity to IgG class of antibodies against scrub typhus was done using Scrub typhus detect IgG ELISA kit as per manufacturers protocol. RESULT Seroprevalence of scrub typhus in seven districts of Arunachal Pradesh was found to be 40% (120/300). The age-specific scrub typhus seroprevalence rose steadily from 5.6% in children <10 years of age to 61.8% in persons aged ≥40 years (p = 0.0001). Prevalence is lowest in Papumpare (25.9%) and highest in East Siang (72.5%) (p = 0.0001). The seroprevalence in males and females was very similar, however, the female prevalence increases from age group ≥30 years (p = 0.053). Moreover, among the farmers, the seroprevalence is higher (58.3%) (p = 0.0001). CONCLUSIONS As clinical symptoms overlap with other viral/bacterial infections, scrub typhus infection should be considered in differential diagnosis of any acute febrile illness in this part of the country. In view of the high prevalence, empirical therapy of doxycycline/azithromycin may be done in cases of undiagnosed fever. Active surveillance has to be done to understand exact magnitude, epidemiological aspects, and distribution of vector and disease of this reemerging neglected tropical disease.

Distribution of human papilloma virus infections of uterine cervix among women of reproductive age--a cross sectional hospital-based study from North East India.

UNLABELLED Infection of the uterine cervix by human papilloma viruses (HPV) may be associated with cervical pre-cancer and invasive cervical carcinoma if left untreated. With advance in molecular techniques, it has become easier to detect the resence of HPV DNA long before the appearance of any lesion. This study concerned cervical scrape samples of 310 married non-pregnant women attending a gynecology outpatient department for both Pap and PCR testing to detect HPV DNA. Nested PCR using primers for L1 consensus gene with My9/My11 and GP6+/ GP5+followed by multiplex PCR were carried out to detect HPV 16 and HPV18. RESULT HPV prevalence was 11.9% out of which 3.67% cases of negative for intra-epithelial lesion or malignancy (NILM) and in 71.1% (27/38) of atypical cervical smears were HPV positive. There was increasing trend of high-risk-HPV positivity (HR HPV 16 and 18), from 20% in benign cytology (NILM) to 42.9 % in LSIL, 71.41% in HSIL and 100% in SCC. There was highly significant association of HPV infection with cervical lesion (x2=144.0, p<0.01) and also with type specific HPV prevalence (x2=7.761*(p<0.05).

Circumcision and herpes simplex virus-2 infection among spouses

Herpes simplex virus-2 (HSV-2) has been found to facilitate the acquisition of HIV by more than two times in observational studies.1 Recent controlled studies by Tobian et al 2 have documented the efficacy of male circumcision in reducing the incidence of HSV-2 infection. However, the effect of male circumcision on acquisition of HSV-2 infection in sexual partners or …

Polymorphism of HLA class I and class II alleles in influenza A(H1N1)pdm09 virus infected population of Assam, Northeast India

Human leucocyte antigen (HLA) represents one of the most highly polymorphic systems which plays a central role in the immune response. Genetic polymorphism of HLA in influenza A(H1N1)pdm09 infected population may be an important factor in disease progression and severity that needs further probing. In this study, a total of 110 Influenza like illness patients were recruited from the population of Assam, Northeast India, from which 35 cases infected by A(H1N1)pdm09 viruses and 35 controls were typed for HLA‐A, B and DRB1 locus by PCR‐SSP method. A total of seven alleles of HLA‐A, 16 alleles of HLA‐B, and 11 alleles of HLA‐DRB1 locus were identified. The most common alleles within each locus in cases were HLA‐A*11 (85.71%, P = 0.046), HLA‐B*35 (25%, P = 0.0001), and HLA‐DRB1*15 (49.35%,  P = 0.133) as compared to the controls, HLA‐A*11 (40.82%), HLA‐B*35 (0.00%), and HLA‐DRB1*15 (67.53%). The frequency of HLA‐A*11 and HLA‐B*35 were significantly higher in cases as compared to the controls. In DRB1 locus, HLA‐DRB1*10 was significantly higher in cases (20.78%, P = 0.005) than that of controls (0.00%). Whereas, HLA‐DRB1*15 showed a higher frequency in controls than in cases. In addition, HLA‐DRB3*01 (P = 0.053), DRB4*01 (P = 1.000), and DRB5*01(P = 0.591) were also identified along with HLA‐DRB1 haplotype. From this preliminary study, it is suspected that there may be a role of HLA‐A*11, HLA‐B*35 and HLA‐DRB1*10 in conferring susceptibility to influenza A(H1N1)pdm09 infection in the study population. A larger extended study on HLA polymorphism may explain the association between HLA and influenza A(H1N1)pdm09 infection and provide insights for HLA restricted peptide based vaccines.

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.

Molecular characterisation and phylogenetic analysis of dengue outbreak in Pasighat, Arunachal Pradesh, Northeast India

Background and Objectives: Dengue is one of the most prevalent arboviral diseases in the world with 390 million dengue infections per year. In this study, we report the molecular characterisation of dengue outbreak in Pasighat, Arunachal Pradesh, Northeast India during 2015. Subjects and Methods: A total of 613 dengue-suspected cases were screened for dengue virus by dengue NS1 Ag and anti-dengue IgM antibody depending on the duration of sample collection and onset of symptom. Further, molecular characterisation was done by amplifying the C-PrM region by real-time polymerase chain reaction followed by phylogenetic analysis. Results: Molecular characterisation revealed that the dengue outbreak was predominantly due to dengue virus serotype-1 (DENV-1) (90.9%) while DENV-2 was detected in 7.5% of samples. Co-infection of DENV-1 and DENV-2 was detected in one case. Phylogenetic analysis of the DENV-1 strains with the prototype revealed that the DENV-1 strains were grouped within genotype III. Similarly, DENV-2 strains were clustered within genotype IV. The study revealed a change in the predominant serotype in recent years with DENV-3 in 2012 to DENV-1, 2, 3 and 4 in 2014 to DENV-1 in 2015 in the study region. A unique L24M mutation was observed in the DENV-1 strains of Arunachal Pradesh which was absent in all the circulating strains in India except one strain from the state of Kerala in South India. Marked variation within the DENV-2 strains was observed at A102V and I163V in one strain similar to earlier circulating isolates in India. Conclusions: The present study reveals a shift in the serotype dominance in the study region. As serotype shifts and secondary infection with a heterologous DENV serotype are frequently associated with disease severity, there is an urgent need for sustained monitoring of the circulating serotypes and enhanced surveillance operations, especially in the monsoon and post-monsoon periods to prevent large-scale, severe dengue outbreaks in this region.