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Biomedical subjects

D N Mazumder

Publications and source records attributed to D N Mazumder.

At least 19 recordsLinked to original sources

Hepatic damage caused by chronic arsenic toxicity in experimental animals.

OBJECTIVE: Noncirrhotic fibrosis of the liver is common in subjects chronically consuming ground water geologically contaminated with arsenic, but the mechanism of the hepatic fibrosis is not known. Because lipid peroxidation has been implicated in the development of several other forms of hepatic fibrosis, including iron and copper overload, we have explored the roles of oxidative stress and lipid peroxidation in the causation of hepatic fibrosis in a murine model of chronic arsenic toxicity. METHODS: Male BALB/c mice were given drinking water contaminated with arsenic (3.2 mg/L) or arsenic-free (<0.01 mg/L, control) ad libitum. Mice were sacrificed at 3, 6, 9, 12, and 15 months for examination of hepatic histology and assays of hepatic reduced glutathione content, lipid peroxidation, enzymes of the antioxidant defense system, and membrane-bound sodium/potassium ATPase (Na+/K+ ATPase). RESULTS: After 12 months of arsenic feeding, the liver weights increased significantly as did serum aspartate aminotransferase and alanine aminotransferase. After 6 months of arsenic feeding, hepatic glutathione and the enzymes glucose-6-phosphate dehydrogenase and glutathione peroxidase were significantly lower than those of the control group. Hepatic catalase activity was significantly reduced at 9 months in the arsenic-fed group, while glutathione-S-transferase and glutathione reductase activities were also significantly reduced at 12 and 15 months. Plasma membrane Na+/K+ ATPase activity was reduced after 6 months while lipid peroxidation increased significantly after 6 months of arsenic feeding. Liver histology remained normal for the first 9 months, but showed fatty infiltration after 12 months of arsenic feeding. Histologic evidence of fibrosis was observed after 15 months. CONCLUSION: We have demonstrated hepatic fibrosis due to long-term arsenic toxicity in an animal model. Initial biochemical evidence of hepatic membrane damage, probably due to reduction of glutathione and antioxidant enzymes, may be seen by 6 months. Continued arsenic feeding resulted in fatty liver with serum aminotransferase and alanine aminotransferase elevated at 12 months and hepatic fibrosis at 15 months. The murine model is proposed as relevant to epidemic human toxicity in areas of arsenic contamination.

Alanine Transaminase↗

Arsenic in drinking water and the prevalence of respiratory effects in West Bengal, India.

BACKGROUND: A large population in West Bengal, India has been exposed to naturally occurring inorganic arsenic through their drinking water. A cross-sectional survey involving 7683 participants of all ages was conducted in an arsenic-affected region between April 1995 and March 1996. The main focus of the study was skin keratoses and pigmentation alterations, two characteristic signs of ingested inorganic arsenic. Strong exposure-response gradients were found for these skin lesions. The study also collected limited information concerning respiratory system signs and symptoms, which we report here because increasing evidence suggests that arsenic ingestion also causes pulmonary effects. METHODS: Participants were clinically examined and interviewed, and the arsenic content in their current primary drinking water source was measured. There were few smokers and analyses were confined to non-smokers (N = 6864 participants). RESULTS: Among both males and females, the prevalence of cough, shortness of breath, and chest sounds (crepitations and/or rhonchi) in the lungs rose with increasing arsenic concentrations in drinking water. These respiratory effects were most pronounced in individuals with high arsenic water concentrations who also had skin lesions. Prevalence odds ratio (POR) estimates were markedly increased for participants with arsenic-induced skin lesions who also had high levels of arsenic in their current drinking water source (> or = 500 microg/l) compared with individuals who had normal skin and were exposed to low levels of arsenic (<50 microg/l). In participants with skin lesions, the age-adjusted POR estimates for cough were 7.8 for females (95% CI : 3.1-19.5) and 5.0 for males (95% CI : 2.6-9.9); for chest sounds POR for females was 9.6 (95% CI : 4.0-22.9) and for males 6.9 (95% CI : 3.1-15.0). The POR for shortness of breath in females was 23.2 (95% CI : 5.8-92.8) and in males 3.7 (95% CI : 1.3-10.6). CONCLUSION: These results add to evidence that long-term ingestion of inorganic arsenic can cause respiratory effects.

Adolescent↗

Arsenic-induced skin lesions among Atacameño people in Northern Chile despite good nutrition and centuries of exposure.

It has been suggested that the indigenous Atacameño people in Northern Chile might be protected from the health effects of arsenic in drinking water because of many centuries of exposure. Here we report on the first intensive investigation of arsenic-induced skin lesions in this population. We selected 11 families (44 participants) from the village of Chiu Chiu, which is supplied with water containing between 750 and 800 microg/L inorganic arsenic. For comparison, 8 families (31 participants) were also selected from a village where the water contains approximately 10 microg/L inorganic arsenic. After being transported to the nearest city for blind assessment, participants were examined by four physicians with experience in studying arsenic-induced lesions. Four of the six men from the exposed village, who had been drinking the contaminated water for more than 20 years, were diagnosed with skin lesions due to arsenic, but none of the women had definite lesions. A 13-year-old girl had definite skin pigmentation changes due to arsenic, and a 19-year-old boy had both pigmentation changes and keratoses on the palms of his hands and the soles of his feet. Family interviews identified a wide range of fruits and vegetables consumed daily by the affected participants, as well as the weekly intake of red meat and chicken. However, the prevalence of skin lesions among men and children in the small population studied was similar to that reported with corresponding arsenic drinking water concentrations in both Taiwan and West Bengal, India--populations in which extensive malnutrition has been thought to increase susceptibility.

Adolescent↗

Histopathology of skin lesions in chronic arsenic toxicity--grading of changes and study of proliferative markers.

Chronic arsenic toxicity (CAT) manifests predominantly as cutaneous lesions in the form of melanosis, keratosis and neoplastic changes. We have studied skin biopsies from 42 patients of CAT. Histological study of H/E stained sections showed--hyperkeratosis in 13, parakeratosis in 13, acanthosis in 12, papillomatosis in 24, elongation of reteridges in 21, increased basal pigmentation in 27 and dysplastic changes in 8 cases. Squamous cell carcinoma was present in 2, basisquamous in 1 and basal cell carcinoma in 1 case. Changes of skin lesions after drug DMSA and DMPS therapy compared to placebo were studied. The result was inconclusive. Proliferative activity of skin lesions in CAT were studied by AgNOR stain to assess the biological behaviour of the lesions. AgNOR score showed--normal control 1.08, benign changes (e.g. Hyperkeratosis, parakeratosis, acanthosis, papillomatosis etc.) without dysplasia--1.35, mild to moderate dysplasia--1.735, severe dysplasia--3.0 and carcinoma--3.56. Thus, AgNOR score gives some idea on the biological behaviour of CAT lesions. It is suggested that AgNOR staining should be done regularly along with H&E staining for proper assessment of the cases.

Adolescent↗

Pigmented nails and Strongyloides stercoralis infestation causing clinical worsening in a patient treated for immunoproliferative small intestinal disease: two unusual observations.

Immunoproliferative small intestinal disease (IPSID) is commonly reported from developing countries with poor socioeconomic conditions, hygiene, and high frequency of gastrointestinal infections and infestations. The disease requires anti-malignant chemotherapy in lymphomatous stage. Reported here is a 20-year old man with IPSID lymphoma who responded to anti-malignant chemotherapy initially, but later deteriorated due to Strongyloides stercoralis infestation, which was treated successfully with mebendazole. Importance of an early recognition and adequate treatment for gastrointestinal infections and infestations before anti-malignant chemotherapy for this disease is highlighted considering the occurrence of this disease in the developing world. The patient developed alternate brown black and white lines in the finger nails after combination chemotherapy, which has not been reported earlier in this disease; the nail changes disappeared 6 months after the withdrawal of doxorubicin suggesting this drug as the cause for such nail changes during anti-malignant combination chemotherapy.

Adult↗

Prevention of carbon tetrachloride-induced hepatic injury in mice by Picrorhiza kurrooa.

OBJECTIVE: Picrorhiza kurrooa (Pk) has been used in liver diseases in the Indian indigenous system of medicine. We undertook this study to determine whether Pk extract possesses hepatoprotective function and if so to determine its nature and mechanism. METHODS: Liver injury was induced in 16 mice by thrice-a-week injection of carbon tetrachloride (CCl4) for nine weeks. Eight of them were given daily feeding of Pk extract (12 mg/Kg) 10 days prior to CCl4 injection. Control mice (n = 6) were injected with olive oil for the same period. Serum markers of liver injury and histology of liver tissues were studied. Hepatic glutathione (GSH), total thiol (-SH), glucose 6-phosphate dehydrogenase (G6PD), catalase, lipid peroxidation and plasma membrane-bound Na+/K+ ATPase were also determined. RESULTS: CCl4 treatment resulted in significant elevation of serum ALT and AST. Liver GSH [6.3 (0.7) vs control 10.5 (1.1) micrograms/mg protein], -SH, G6PD, catalase and membrane-bound Na+/K+ AT-Pase [164.3 (23.2) vs control 358.4 (12.9) nmole pi released/min/mg protein] were significantly reduced. Significant increase of lipid peroxidation [3.0 (0.6) vs control 1.0 (0.3) nmole MDA/mg protein] and histologic changes characteristic of liver injury were also seen. Feeding of Pk extract in CCl4-treated mice caused significantly less alteration of serum ALT, AST, liver GSH [8.9 (0.7) micrograms/mg protein], -SH, G6PD, catalase and membrane-bound Na+/K+ ATPase [270.8 (21.3) nmole pi released/min/mg protein]. Histologic lesions of liver and lipid peroxidation [1.7 (0.4) nmole MDA/mg protein] were also significantly less in these animals. CONCLUSION: The extract of Pk appears to offer significant protection against liver damage by CCl4. It probably acts as free-radical scavenger and inhibitor of lipid peroxidation of liver plasma membrane.

Animals↗

Portal hypertensive gastropathy and gastric varices before esophageal variceal sclerotherapy and after obliteration.

OBJECTIVES: To evaluate the frequency and clinical importance of portal hypertensive gastropathy (PHG) and gastric varices (GV) before endoscopic sclerotherapy (EST) and after esophageal variceal obliteration. METHODS: Patients with portal hypertension (PHT) with variceal bleed were prospectively evaluated for PHG and GV before EST with intravariceal injection of absolute alcohol and after esophageal variceal obliteration. Gastric varices and PHG were characterized and graded according to previously established criteria. Patients were followed up for 12-48 (mean 37) months after variceal obliteration. RESULTS: Of 70 patients with PHT 26 had PHG before (severe in two) [18/37 in cirrhosis, 6/20 in non-cirrhotic portal fibrosis (NCPF), and 2/13 in extrahepatic portal vein obstruction (EHPVO)] and 50 had PHG after variceal obliteration (severe in 22) (27/37 in cirrhosis, p = 0.03 before versus after esophageal variceal obliteration; 16/20 in NCPF, p < 0.01; and 7/13 in EHPVO, p = ns). Type I GV (continuation of esophageal varix into the stomach) was found in 25/70 before and 5/70 after esophageal variceal obliteration (p < 0.001); in contrast, other types of GV were seen in 14/70 before and 29/70 after (p < 0.01). Overt bleeding from GV and PHG during follow-up after variceal obliteration occurred in 6 and 4 patients, respectively. CONCLUSIONS: Esophageal variceal obliteration by EST increases the frequency of PHG and GV (except type I GV which get obliterated); both PHG and GV have potential to cause rebleeding.

Adolescent↗

Natural history of severe duodenal ulcer disease.

BACKGROUND: A subset of patients with chronic duodenal ulcer has severe ulcer diathesis in the form of frequent relapses and complications like perforation and hemorrhage. We observed the effect of drug treatment on the natural history of this subset. METHODS: Of 526 patients diagnosed to have chronic duodenal ulcer by endoscopy, 23 patients with severe diathesis were available for long follow-up (mean period 36 months). Each patient was assessed clinically and endoscopically every 2 months for at least 12 months and then every 3 months or when symptomatic. Helicobacter pylori status was assessed during endoscopy. The effect of antisecretory drugs and anti-H. pylori therapy on natural history was determined. RESULTS: Thirteen of 23 patients (56%) had refractory ulcers; six responded to double dose of H2-receptor antagonists (H2RA) for 8 weeks and six to omeprazole 40 mg daily for 4-8 weeks. Of 20 patients (87%) who were H. pylori-positive, 15 completed triple-drug therapy; of these, 10 patients eradicated H. pylori. These 10 patients were followed up for 24 months; there were no ulcer relapses within the first 12 months but 8 of them relapsed between 12 and 24 months (total number of relapses 8). Reinfection with H. pylori occurred in 3 patients. In the other 10 patients who remained H. pylori-positive, there were 19 episodes of ulcer relapse in 7 patients over 24 months, in spite of maintenance therapy with H2RA (p < 0.05). CONCLUSIONS: Refractoriness in patients with severe ulcer disease is usually episodic and amenable to larger doses of omeprazole or H2RA. Anti-H. pylori therapy improves the natural history but its effect in preventing ulcer relapse is short lasting (less than 12 months). Recurrence of infection is a problem in our population.

Adult↗

Chronic arsenic toxicity in west Bengal--the worst calamity in the world.

Since 1983 large number of people are being encountered with arsenic toxicity due to drinking of arsenic contaminated water (0.05-3.2 mg/l) in 6 districts of West Bengal. Clinical and various laboratory investigations were carried out on 156 patients to ascertain the nature and degree of morbidity and mortality that occurred due to chronic arsenic toxicity. All the patients studied had typical rain drop like skin pigmentation (being inclusion criteria) while thickening of palm and sole were found in 65.5% patients. Other features included weakness (70%), gastro-intestinal symptoms (58.6%), involvement of respiratory system (57.08%) and nervous system (50.6%). Lung function tests showed restrictive lung disease in 53% (9/17) and combined obstructive and restrictive lung disease in 41% (7/17) of patients. Abnormal electromyography was found in 34.8% (10/29) and altered nerve conduction velocity in 34.8% (10/29) of cases. Enlargement of liver was found in 120 cases (76.9%) while splenomegaly in 31.4% cases. Liver function test showed elevated globulin level in 15.8% and alkaline phosphatase in 51.3%, alanine amino transferase (ALT) in 11.8% and aspartate amino transferase (AST) in 27.6% of cases. Evidence of portal hypertension was found in 33.3% patients. Liver biopsy reports of 45 patients showed non-cirrhotic portal fibrosis in 41, cirrhosis in 2 and normal histology in 2 cases. There was no correlation between the quantity of arsenic taken through water and the level of arsenic in hair, nail, liver tissues and the degree of fibrosis. There were 5 deaths of which one had skin cancer. The various non-cancer manifestations which were observed in these patients were much severe than those reported in similar cases in other parts of the world.

Adolescent↗

Primary pulmonary hypertension in non-cirrhotic portal fibrosis.

BACKGROUND: Primary pulmonary hypertension (PPH) has been reported in association with cirrhosis and extrahepatic portal venous obstruction; reports of PPH in noncirrhotic portal fibrosis (NCPF) are few. AIM: To evaluate pulmonary arterial pressure in patients with NCPF. METHODS: Twenty two patients with NCPF underwent hemodynamic studies for pulmonary arterial pressure after excluding secondary causes of pulmonary hypertension. Hemodynamic studies were carried out through the femoral route using 7F Swan-Ganz catheter. Splenoportal venography was done by percutaneous splenic puncture. RESULTS: The mean pulmonary arterial pressure was 12.9 +/- 3.1 mmHg with pulmonary capillary wedge pressure of 8.3 +/- 2.1 mmHg in 20 of 22 cases; in the remaining two cases, the corresponding pressures were 30 mmHg and 28 mmHg and 13 mmHg and 12 mmHg, respectively. CONCLUSION: Two of 22 patients with NCPF had PPH. PPH can thus develop without hepatocellular failure or recurrent embolization from portal axis thrombosis as has been described in cirrhosis.

Adult↗

Evaluation of IgG4 response in ascariasis by ELISA for serodiagnosis.

The excretory/secretory (ES) antigen(s) of Ascaris lumbricoides was fractionated into 10 fractions by gel chromatography on a Suparose 12 column in FPLC. Of these, the third fraction (Al III), showing binding activity with both IgE and IgG antibodies of A. lumbricoides infected patients' sera, was further resolved into 2 fractions (Al IIIa and Al IIIb) on passage through a Mono Q column. Al IIIb was found to be the most potent antigen due to its high binding affinity with IgE and IgG antibodies of Ascaris infected patients as evidenced by ELISA inhibition. Although a two to five-fold increase of serum IgE level was observed in all helminthic parasite infected patients studied compared to control subjects, Al IIIb specific IgE was detected in sera of all Ascaris infected and only 40% of hookworm infected patients. When Al IIIb was tested by ELISA with sera of control subjects, Ascaris, hookworm, Strongyloides and Trichuris infected patients, strong binding was observed with the IgE and also IgG of all the Ascaris infected patients; however, it cross-reacted with IgG in 50% of hookworm, 28.6% of Trichuris trichura and 22.2% of Strongyloides infected patients' sera; but with IgE only in 40% of hookworm infected patients' sera. Further study showed specific detection of IgG4 in all the serum samples of 65 Ascaris infected patients when Al IIIb antigen was allowed to react with different subclasses of IgG by ELISA, giving a sensitivity of 100%. Reactivities of Al IIIb with IgG1 and IgG3 were only 47.6 and 11.8% respectively and there was no reactivity with IgG2 subclass. No IgG4 reactivity against Al IIIb was observed in the sera of hookworm, Trichuris or Strongyloides infected patients and was similar to that observed with control subjects showing the 100% specificity of the test system. This study may therefore be regarded as a novel technique for serodiagnosis of ascariasis by measuring Ascaris specific IgG4.

Adolescent↗

A study of nosocomial diarrhea in Calcutta.

BACKGROUND: Nosocomial infection is a major problem in hospitalized patients, particularly those who are debilitated. These infections may manifest as diarrhea. The spectrum of infections agents causing nosocomial diarrhea in our country is not known. METHODS: Thirty-two patients, admitted to the hospital with various complaints, who developed diarrhea during their hospital stay, were studied to identify the causative agents of diarrhea. Hospital food samples were also processed for pathogens. RESULTS: The bacteria isolated from patients included established enteropathogens like Salmonella, enteropathogenic Escherichia coli, Campylobacter species and organisms with low pathogenicity like Serratia marsescens, Pseudomonas aeruginosa and Morganella morganii. The bacterial pathogens isolated were resistant to most antibiotics, suggesting their nosocomial character. Hospital food samples contained Salmonella typhimurium, Campylobacter jejuni (biotype 1) and enteropathogenic Escherichia coli, suggesting that food might have been the vehicle for these infections. CONCLUSION: Nosocomial infection was found to be an important cause of diarrhea (34%), EPEC and Salmonell being the predominant pathogens. Water, egg and milk were the source of infection in these cases. Special measures to obtain uneffected items will prevent occurrence of nosocomial diarrhea in our hospitals.

Adult↗