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Biomedical subjects

S Nundy

Publications and source records attributed to S Nundy.

At least 37 records · Page 2Linked to original sources
PubMed1995

Cytoskeletal organization in clusters of isolated polarized skate hepatocytes: structural and functional evidence for microtubule-dependent transcytosis.

Isolated hepatocytes from the marine vertebrate Raja erinacea (the little skate) retain their structural and functional integrity as clusters of cells formed around a single tubular bile canaliculus, and therefore can be used as a model of polarized hepatocytes in situ. In this study we used confocal and conventional epifluorescence microscopy in conjunction with fluorescent markers and immunocytochemistry to examine the structure and function of the cytoskeleton in these cells. Actin filaments in the hepatocyte clusters were found cortically and also concentrated in a pericanalicular array, while microtubules appeared to radiate away from a concentration near the apical membrane of the biliary pole towards the basolateral sinusoidal surfaces. Treatment of clusters with the microtubule disrupting agent, nocodazole, resulted in the microtubules depolymerizing from the basolateral surfaces towards the apical surface, indicating that the microtubules were oriented with their plus ends at the basolateral surface and their minus ends at the apical surface. Nocodazole was also found to disrupt the ability of clusters to transcytose a fluorescent bile salt derivative into their canalicular lumens. We detected cytoplasmic dynein in skate hepatocyte homogenates by Western blotting using an anti-dynein intermediate chain antibody, and immunofluorescent staining of intact hepatocytes revealed a punctate vesicular pattern. The polarized arrangement of microtubules, the presence of cytoplasmic dynein, and the inhibition of bile salt secretion by nocodozole are consistent with the microtubule cytoskeleton playing a fundamental role in the mediation of transcytosis, endocytosis, and bile excretory function in these hepatocytes. These polarized isolated skate hepatocytes represent an excellent experimental model for the in vitro study of hepatic transport, and allow for important comparative studies aimed at elucidating the evolutionarily conserved nature of various hepatocyte structures amongst the vertebrates.

Actins↗
PubMed1994

Proximal splenorenal shunts for extrahepatic portal venous obstruction in children.

OBJECTIVE: The results of proximal splenorenal shunts done in children with extrahepatic portal venous obstruction were evaluated. SUMMARY BACKGROUND DATA: Extrahepatic portal venous obstruction, a common cause of portal hypertension in children in India, is being treated increasingly by endoscopic sclerotherapy instead of by proximal splenorenal shunt. It is believed that surgery (or the operation) carries high mortality and rebleeding rates and is followed by portosystemic encephalopathy and postsplenectomy sepsis. However, a proximal splenorenal shunt is a definitive procedure that may be more suitable for children, particularly those who have limited access to medical facilities and safe blood transfusion. METHODS: Between 1976 and 1992, the authors performed 160 splenorenal shunts in children. Twenty were emergency procedures for uncontrollable bleeding and 140 were elective procedures--102 for recurrent bleeding and 38 for hypersplenism. RESULTS: The overall operative mortality rate was 1.9%--10% (3/160-2/20) after emergency operations and 0.7% (1/140) after elective operations. Rebleeding occurred in 17 patients (11%), and pneumococcal meningitis developed in 1 patient who recovered later. Encephalopathy did not develop in any patient. Four patients died in the follow-up period--two of rebleeding, one of chronic renal failure and a subphrenic abscess, and one of unknown causes. The 15-year survival rate by life table analysis was 95%. CONCLUSIONS: A proximal splenorenal shunt, a one-time procedure with a low mortality rate and good long-term results, is an effective treatment for children in India with extrahepatic portal venous obstruction.

Adolescent↗
PubMed1993

Management of hepatic venous outflow obstruction.

Hepatic venous outflow obstruction (HVOO) is a rare cause of portal hypertension and conservative treatment is usually ineffective. A large series of patients gave us an opportunity to devise a management protocol for this disorder. Between 1978 and 1992, we prospectively studied 75 patients with HVOO. The obstruction was in the hepatic vein in 24, in the inferior vena cava (IVC) in 44, and in both in 7. For hepatic vein obstruction proximal splenorenal shunts were done in 7 (2 died postoperatively); 4 shunts blocked and only 1 patient became completely symptom free. In 2 patients with partial obstruction we performed balloon dilatation of the right hepatic veins but within 6 months the obstruction recurred. In the next 6 patients we constructed a side-to-side portocaval shunt; 2 died of encephalopathy after discharge and 4 are alive and well. For IVC obstruction, after surgical procedures had yielded poor results in 14 patients, we changed to balloon angioplasty which was successful in 28 of the 30 other patients; restenosis occurred in 4. Of the 7 patients with a combined block, 3 have had balloon angioplasty followed by a side-to-side portocaval shunt; 1 died, 2 are well, and the remainder have not completed treatment. Of our 75 patients, 22 have died (5 in hospital and 17 after discharge), 7 have not completed treatment, and 2 have been lost to follow-up. However, 44 are symptom free. We did not encounter any case of hepatocellular carcinoma. We suggest that patients with HVOO should be actively managed with a side-to-side portocaval shunt for hepatic vein obstruction, balloon angioplasty for inferior vena caval obstruction, and perhaps both procedures for those with combined obstructions.

Adolescent↗
PubMed1992

Indian medical journals.

Although Indian doctors produce half the articles published from the third world, little has been written about Indian medical journals. We examined 75 of the 113 serious English-language journals published in India. Of the 22 included in the Cumulated Index Medicus only 8 were judged by Indian and foreign referees to be of international standard. A survey of Indian authors indicated that foreign journals were chosen for the best papers because of their wider circulation, better refereeing practices, and punctuality. More than 98% of medical articles from India probably go unnoticed by the international medical community.

Attitude of Health Personnel↗
PubMed1992

Encephalopathy in patients with extrahepatic obstruction after lienorenal shunts.

Thirty patients with portal hypertension resulting from extrahepatic portal vein obstruction were studied. Evidence of postshunt encephalopathy was sought using neurological and psychometric tests and visual evoked potentials. Eleven patients were studied before and after lienorenal shunt operations and 19 at varying intervals, from 6 to 123 (median 26) months, after the same procedure. All the shunts were patent and none of the patients developed clinical or subclinical encephalopathy. In patients with extrahepatic portal vein obstruction, a lienorenal shunt does not appear to be associated with postshunt encephalopathy.

Adolescent↗
PubMed1989

Accuracy of abdominal ultrasonography and the role of a second investigation in surgical obstructive jaundice.

The diagnostic accuracy of ultrasonography (US) was evaluated in delineating the site and cause of biliary obstruction in 59 patients of surgical obstructive jaundice (SOJ). A final analysis of the ultrasonographic data was carried out in 42 patients on whom laparotomy or endoscopic papillotomy with removal of common bile duct stones, confirmed the diagnosis. Evaluation of the role of second investigation following ultrasound in 28 patients (side-viewing endoscopy in 13, ERCP in 12 and PTC in 3) was also done to determine whether they provide any additional information over ultrasonography in delineating the exact level and etiology of biliary obstruction. US was done by the clinician who interpreted the findings in conjunction with the clinical profile of the patient. US correctly diagnosed SOJ in all 42 patients. In 26 of the 28 patients with distal CBD block (specificity 87.5%; sensitivity 100%) and in 14 out of 16 patients with proximal CBD block (specificity 100%; sensitivity 87.5%) US provided and accurate diagnosis of the site of obstruction. US was correct in diagnosing a malignant etiology in 26 out of 27 malignant cases whereas it accurately indentified the benign nature of biliary obstruction in 14 of the 15 patients of SOJ due to benign obstruction (specificity and sensitivity range 93.3% to 96.3%). A second investigation could correctly change the etiology and site of biliary obstruction in only 5 patients (17.9%) whereas in the remaining 23 patients (82.1%) it did not add any additional information over the US findings. Six out of fifteen patients (40%) who underwent cholangiography had cholangitis and in one severe septicemia led to death.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1989

Ultrasonography in portal hypertension: a sensitive noninvasive test to demonstrate portal-vascular anatomy.

The accuracy of ultrasonography (US) in delineating the portal vascular anatomy was assessed clinically by the clinician in 30 cases of portal hypertension due to noncirrhotic portal fibrosis and extra hepatic portal venous obstruction. Ultrasonography detected portal vein block in 19 and in 11 patients it was found to be patent. These ultrasonic diagnoses were confirmed by spleno-portovenography (SPV) in all, except in 2 cases due to technical failure. Ultrasononic assessment of the splenic vein was found to be accurate in 93.3% (28/30) of cases. SPV also had similar accuracy of splenic vein assessment when compared with the surgical findings. In one patient, intraperitoneal haemorrhage was encounted following SPV, necessitating emergency surgery. Thus, US was found to be as accurate as splenoportovenography in the assessment of portal vascular anatomy. The imaging technique is cheap, easy, safe, and can be repeated as often as necessary. It should be the procedure of choice in assessing the anatomy of portal vascular system.

Adult↗
PubMed1988

Common bile duct obstruction by portal cavernoma.

Obstructive jaundice occurring in a patient with portal hypertension is a rare association. In this report, a 24-year-old patient is described who had biliary obstruction due to a portal cavernoma compressing the common bile duct and in whom surgical decompression of the portal system resulted in relief of the biliary obstruction, thus proving that the dilated portal vein collaterals were compressing the biliary tract and producing jaundice. Although biliary obstruction due to a portal cavernoma has been described earlier, this is, to the best of our knowledge, the first case described in which improvement followed shunt surgery.

Adult↗
PubMed1988

Spontaneous massive gastrointestinal hemorrhage in patients with pancreatitis.

Spontaneous massive gastrointestinal hemorrhage occurring in patients with pancreatitis is an uncommon and difficult clinical problem, especially in a tropical third world country where the underlying causes of pancreatitis and facilities for its diagnosis and management are different from those in the developed West. Of 7 such cases seen by us in 3 years, 2 were due to hemosuccus pancreaticus, 2 were due to gastric variceal hemorrhage consequent to splenic vein obstruction, and one each due to contiguous pancreatic inflammation involving the duodenum, an aneurysmal bleed from the left gastric artery and a pseudocyst rupturing into the transverse colon. A fiberoptic endoscopic examination was helpful in all the 7 cases and delineated the cause of bleeding, whereas angiography, performed in 4 patients contributed little to management. The mortality rate was 14%. It is suggested that a timely endoscopic examination during active bleeding, which may be repeated if necessary, is extremely rewarding in the diagnosis and management of such patients and often obviates the necessity of angiography which is a time-consuming and cumbersome investigation in a critically ill patient and facilities for which are usually not available in most third world country hospitals.

Adult↗
PubMed1988

Chronic calcific pancreatitis: clinical profile in northern India.

Twenty three patients with chronic calcific pancreatitis of the tropics in Northern India were prospectively studied. All had pancreatic calcification and ERCP changes typical of chronic pancreatitis, the most predominant being ductal dilatation which was detected in all patients by both ERCP and by ultrasonography. Pain was present in 19 (83%) patients and diabetes in 11 (48%) patients. Exocrine pancreatic dysfunction was uncommon, steatorrhoea being present in only 9% of patients. Ten of the 11 patients with diabetes required insulin for control and one case was able to be controlled by an oral antidiabetic agent. Two patients developed ketoacidosis during acute episodes of pancreatitis, 3 patients had peripheral neuropathy and one patient had visual changes. Recurrent severe pain was the reason for operation in 7 patients. All had a lateral pancreaticojejunostomy. In order to obtain an objective assessment of pain, a scoring system was developed to grade its severity according to its intensity, frequency and consequences. Six patients who preoperatively had a pain score of 15 or more (out of a maximum score of 24) attained significant relief after the surgery. We feel this scoring system may provide an easy objective assessment of pain in the subsequent follow-up of these patients.

Adolescent↗
PubMed1987

Operations for portal hypertension due to extrahepatic obstruction: results and 10 year follow up.

Between 1976 and 1984, 136 patients with portal hypertension due to extrahepatic obstruction were operated on. Twenty two patients had emergency and 114 elective operations. The operative mortality was 9% and 1%, respectively. Altogether 117 patients (86%) were followed up for from two to 10 years: 17 rebled, none developed encephalopathy or sepsis after splenectomy, and 90% and 75% were alive at five and 10 years respectively. Unlike endoscopic sclerotherapy and treatment with propranolol, operative treatment of variceal bleeding can usually be completed during one admission and carries a low mortality and a fairly low morbidity. Operation seems to be the best form of treatment for poor patients living far from medical facilities in developing countries and may be the treatment of choice in developed countries as well.

Adolescent↗
PubMed1987

Use of sodium nitroprusside induced hypotensive anaesthesia for reducing blood loss in patients undergoing lienorenal shunts for portal hypertension.

A randomized study was performed on 18 patients to determine whether hypotensive anaesthesia, induced by sodium nitroprusside (SNP), would reduce blood loss during elective proximal lienorenal shunt operations for portal hypertension which was due to extrahepatic obstruction or non-cirrhotic portal fibrosis. Eight patients received SNP intraoperatively to reduce the systolic blood pressure to below 95 mmHg, and there were 10 control patients. Blood loss, the number of units of blood transfused, and urine output during surgery were measured together with the postoperative drainage from the abdominal and chest tubes over the first 24 h. There was a significantly lower blood loss (mean +/- s.d. 517 +/- 220 versus 1286 +/- 523 ml; P less than 0.01) and number of units of blood transfused was less (0.9 +/- 0.9 versus 3.0 +/- 1.2; P less than 0.01) in the SNP patients than in the controls. The urine output was greater in the SNP group (606 +/- 211 versus 399 +/- 139 ml, n.s.). Postoperative drainages from the chest and abdomen were similar. Hypotensive anaesthesia with SNP reduces operative blood loss and transfusion requirement in patients with good liver function undergoing proximal lienorenal shunts for portal hypertension.

Adolescent↗