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BACKGROUND AND OBJECTIVES: Hepatitis B virus (HBV) may occasionally be transmitted through transfusion of blood units that are hepatitis B surface antigen (HBsAg) negative but HBV DNA positive. Children with beta-thalassemia are particularly susceptible to HBV because they receive multiple blood transfusions. These children have high infection rates despite vaccination against HBV. Post-vaccination infections may be a result of viruses harbouring surface (S)-gene mutations (e.g. G587A) in a region critical for reactivity to antibody to hepatitis B surface antigen (anti-HBs). The true prevalence of HBV in individuals with beta-thalassemia has not been studied previously. PATIENTS AND METHODS: Seventy patients with beta-thalassemia (median age 6 years; range 8 months to 22 years; 49 male), who had received seven to 623 (median 61) units of blood each and three doses (10/20 micro g) of HBV vaccine (Engerix B) before presentation to us, were included in the study; 50 of the 70 patients had received transfusions prior to vaccination. Enzyme-linked immunoassay for serological markers [HBsAg, antibody to hepatitis B core antigen (anti-HBc) and quantitative anti-HBs] and polymerase chain reaction (PCR) followed by Southern hybridization for molecular detection of hepatitis B, was performed on all samples. The PCR-amplified product was cloned, sequenced and the nucleotide and deduced amino acid sequences for the HBV S and polymerase (P) genes were analysed for mutations. RESULTS: Four of 70 (5.7%) individuals with beta-thalassemia were HBsAg positive and 14 (20%) were anti-HBc positive. The prevalence of serological markers increased with number of transfusions (P < 0.01). Of 70 patients, 53 (75.7%) had an anti-HBs titre of > 10 IU/l following vaccination and 17 (24.3%) were non-responders (< 10 IU/l); 22 (31.4%) of the 70 were DNA positive. The frequency of HBV infection in beta-thalassemia was similar in vaccine responders and non-responders. The virus was of subtype ayw (genotype D) in the five DNA-positive samples in which a 388-nucleotide region of the S gene was sequenced. Mutations occurred at 13 positions in the S gene and at 10 positions in the P gene. Hydrophobicity plots revealed differences in amino acid regions 117-165 and 195-211. Some of these amino acid substitutions coincided with the putative cytotoxic T-lymphocyte epitopes of both S and P proteins. CONCLUSIONS: A high frequency of HBV infection was seen using molecular methods in thalassemic patients. The frequency of infection was similar in vaccine responders and non-responders. A number of mutations were observed in the S gene, which could have implications for viral replication as well as virus-host cell interaction. 相似文献
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F. U. Huwez A. R. McPhaden P. R. Belcher S. K. Naik D. J. Wheatley 《Journal of gastroenterology》1996,31(6):848-850
We report the coexistence of symptomatic viral, bacterial, and fungal infection of the upper gastrointestinal tract in a heart
transplant recipient. Endoscopic findings were normal at all levels but, because of severe symptoms and recent conversion
to positive serology forCytomegalovirus, biopsies were taken. These showed esophageal candidiasis and gastricHelicobacter infection that has hitherto been unreported in cardiac transplant recipients. 相似文献
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Samant Sanika Naik Milind Parulekar Karishma Charya Lakshangy Vaigankar Divya 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(2):747-754
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The present study foregrounds the isolation of selenium tolerant bacteria from Mandovi estuary of Goa, India,... 相似文献
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Akshay Gopinathan Nair Swathi Kaliki Dilip Kumar Mishra Tarjani Vivek Dave Milind N Naik 《Indian journal of ophthalmology》2015,63(7):620-622
Schwannomas are benign, encapsulated, primary neurilemmal tumors composed of proliferating Schwann cells. Schwannomas are commonly seen in the orbit, but are rare on the epibulbar surface. Herein, we report a case of a 12-year-old boy who presented to us with a slow-growing painless subconjunctival mass in the left eye. There was no intraocular extension of the mass and intra-operatively, the mass could be clearly delineated and was excised off the underlying sclera. Histopathological examination of the mass showed typical features of schwannoma and immunohistochemistry helped to confirm the diagnosis. There was no recurrence of the lesion observed at follow-up 26 months after surgery. Here, we describe this uncommon tumor and review the available literature. Although rare, an epibulbar schwannoma should be considered in the differential diagnosis of an amelanotic, painless subconjunctival nodular mass. Excision of the lesion is the recommended treatment. 相似文献
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Arora Shiyana Dharavath Ravinder Naik Bansal Yashika Bishnoi Mahendra Kondepudi Kanthi Kiran Chopra Kanwaljit 《Metabolic brain disease》2021,36(6):1315-1330
Metabolic Brain Disease - The night shift paradigm induces a state of chronic partial sleep deprivation (CPSD) and enhances the vulnerability to neuronal dysfunction. However, the specific neuronal... 相似文献
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Evidence for activation of cellular immune responses in patients with acute hepatitis E. 总被引:1,自引:0,他引:1
Sita Naik Rakesh Aggarwal Subhash R Naik Sunita Dwivedi Sudha Talwar S K Tyagi S D Duhan P Coursaget 《Indian journal of gastroenterology》2002,21(4):149-152
INTRODUCTION: Although acute hepatitis E virus (HEV) infection is known to induce IgM and IgG humoral host immune responses, little is known about occurrence of cellular responses in this infection. We looked for evidence of lymphocyte sensitization to HEV peptides in patients with acute HEV infection. METHODS: peripheral blood lymphocytes were obtained from patients with acute hepatitis E and healthy controls. Proliferation of these lymphocytes in the presence of each of seven peptides with amino acid sequences corresponding to open reading frames 2 and 3 proteins of HEV (3 and 4 peptides, respectively) were studied; no peptide was added to control wells. Proliferative responses with stimulation indices exceeding 3.0 were taken as positive. RESULTS: More patients showed reactivity to two or more HEV peptides than did controls (11/21 vs 5/22, p<0.05). Reactivity to one peptide corresponding to open reading frame 2 of HEV was more frequent in patients than in controls (7/21 vs 1/22, p<0.05). CONCLUSION: Our results show that lymphocytes of patients with acute hepatitis E show sensitization to HEV peptides. This may have significance in understanding the pathogenetic mechanisms of liver injury in this infection. 相似文献
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