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Dr. R. K. Dhiman MD DM V. A. Saraswat MD. DM A. Mishra PhD S. R. Naik MD 《Digestive diseases and sciences》1996,41(4):764-772
Prolonged esophageal pH monitoring is the most accurate method for detecting abnormal gastroesophageal reflux (GER) in patients with gastroesophageal reflux disease (GERD). However, some investigators have found that short-duration postprandial pH monitoring in the upright position is also useful, while others have failed to find such results. Therefore, we have compared a 6-hr period of pH monitoring (3-hr postprandial period after daytime meal and 3-hr supine period) with a total 24-hr period in detecting abnormal gastroesophageal reflux. Sixty-five patients (44 men, mean age 41.3 years) with GERD and 16 healthy volunteers (11 men, mean age 34.3 years) underwent 24-hr pH monitoring according to a standard protocol. Various reflux parameters during 24-hr pH monitoring were compared with reflux parameters during the 6-hr period. Abnormal GER was detected in 56 patients presenting with typical symptoms of GERD (sensitivity 86.2%). These patients could be further divided into upright (N=18), supine (N=15), and combined (N=23) refluxers, depending on the posture in which abnormal reflux occurred. Esophageal pH monitoring during the 3-hr postprandial upright period showed abnormal reflux in only 35 patients (sensitivity 53.8%;P<0.00005, compared with the 24-hr pH monitoring period). Abnormal GER was identified in 13 of 18 upright, 19 of 23 combined, and only one of 15 supine refluxers, as well as in two of nine patients with normal 24-hr pH-metry. However, inclusion of the 3-hr supine monitoring period in the 3-hr postprandial upright period improved detection of abnormal GER to 78.5% (51 patients;P=NS compared with 24-hr pH monitoring period). This was related mainly to improved detection of abnormal GER in supine refluxers (11 of 15; 73.3%). Esophageal acid exposure time correlated significantly with severity of esophagitis only during the total and supine periods of both the 24- and 6-hr periods and not during the upright period. Esophageal acid clearance correlated significantly with increasing grades of esophagitis for the supine and total periods only. We conclude that 3-hr postprandial pH monitoring, as has been conventionally practiced, is not appropriate in the detection of abnormal GER; inclusion of a supine period in the short-duration pH monitoring schedule increases the detection of pathological reflux. We therefore recommend that a supine period should be included in short-duration pH monitoring schedules. We also found that supine reflux was the most important factor in the development of esophagitis. 相似文献
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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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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