Search PubMed⌕ Search

Biomedical subjects

K Singh

Publications and source records attributed to K Singh.

At least 739 records · Page 41Linked to original sources
PubMedDate not supplied

Isolation and characterization of tributyltin resistant mutants of Escherichia coli.

Two classes of tributyltin (TBT) resistant, spontaneous mutants of Escherichia coli K-12 were isolated, using a cytochrome containing (W 1485) and a cytochrome deficient ( SASX76 ) strain. In contrast to the cytochrome sufficient strain, the cytochrome deficient strain was found to be fifty times more sensitive to TBT. The class I mutants, isolated from strain W 1485, also showed cross-resistance to triphenyltin (TPT). As compared to its wild type parent, the TBT-resistant mutants exhibited mucoid colony type, aberrant cell morphology and reduced uptake of TPT. Based on these results, it was suggested that the resistance of class I mutants to TBT may be associated with above mentioned alterations. The class II TBT-resistant mutants were isolated from the cytochrome deficient strain, SASX76 . In comparison to class I mutants, these class II mutants were found to have TBT-resistant membrane bound adenosine triphosphatase (ATPase) which may account for their resistance to TBT.

Adenosine Triphosphatases↗
PubMedDate not supplied

How does service drive the service company?

"How Does Service Drive the Service Company?" presents commentators on Leonard A. Schlesinger and James L. Heskett's September-October article. Commentators include Michael R. Quinlan, Ron Zemke, Jim Snider, Dinah Nemeroff, Steven S. Reinemund, Robert Ayling, Karmjit Singh, James A. Perkins, Joseph E. Antonini, and Walter F. Loeb.

Advertising↗
PubMedDate not supplied

Survival of enteropathogenic Escherichia coli exposed to adverse conditions.

Enteropathogenic Escherichia coli (EPEC) was exposed to different adverse conditions for varying period of time to assess its survival under such circumstances. From the results it is extrapolated that EPEC survive for a very long time when shielded from sunlight and after several hours of exposure to UV irradiation.

Escherichia coli↗
PubMedDate not supplied

A monoclonal antibody-based test system for detection of Entamoeba histolytica-specific coproantigen.

BACKGROUND: Diagnosis of amebiasis based on stool microscopy or demonstration of anti-amebic antibodies has limitations. A diagnostic system based on demonstration of the parasite product in clinical specimens holds promise. METHODS: Murine monoclonal antibodies were developed against an Entamoeba histolytica-specific coproantigen. A monoclonal antibody (MoAb) 3D10 was employed in a double-antibody sandwich microELISA system for the detection of amebic coproantigen in fecal specimens. The system was evaluated in three groups of subjects: 63 patients with intestinal amebae, 27 with non-amebic parasitosis, and 57 apparently healthy controls. RESULTS: The MoAb 3D10 belonged to IgG1 isotype and recognized three antigens, with mol. wt. 36, 25 and 17 kDa in the crude extract of E. histolytica (HM1-IMSS), and an amebic coproantigen with MW 36 kDa in the stool supernatant from patients with intestinal amebae. The coproantigen was detected in the stool eluates of 56 (89%) patients with intestinal amebae and in none of the stool eluates from other subjects, thereby giving this system a sensitivity of 89% and specificity of 100% for the detection of intestinal amebae. CONCLUSIONS: This monoclonal antibody recognizes as intact epitope on the E. histolytica-specific coproantigen. The validity of the MoAb-based microELISA system needs to be established.

Animals↗
PubMedDate not supplied

Detection of Clostridium difficile toxin by an indigenously developed latex agglutination assay.

An indigenously developed latex agglutination assay using C. sordelli antitoxin was used to screen 211 stool samples received from hospitalized patients. Of 126 samples from patients receiving single to multiple antibiotics for various ailments, 38 (30%) were positive by the toxin assay, whereas only 6/85 (7%) of samples of patients not receiving antibiotics were also positive. Thus, of 211 samples a total of 44 (20.8%) were positive by our toxin assay, giving titers ranging from 1 in 5 to 1 in 320. The test developed by us is simple, rapid, easy and reliable and can be easily adapted to all microbiology laboratories.

Anti-Bacterial Agents↗
PubMedDate not supplied

Retained surgical sponge: an unusual cause of malabsorption.

Retained surgical sponge is an unpleasant surprise in clinical practice. Intraluminal migration of the retained sponge, though rare, can lead to intestinal obstruction and other complications. We describe two cases of retained surgical sponge, both following gynaecological surgery, presenting several years after surgery with features of subacute intestinal obstruction, malabsorption and several years after surgery with features of subacute intestinal obstruction, malabsorption and sever hypoproteinemia which reverted after surgical removal.

Adult↗
PubMedDate not supplied

Balloon dilatation in achalasia cardia.

Treatment of achalasia cardia by pneumatic dilatation is an established method. However, data on results of pneumatic dilatation in Indian patients with achalasia cardia are scarce. We report our experience with treatment of achalasia cardia by pneumatic dilatation in 38 patients. The diagnosis of achalasia cardia was based on clinical examination, barium swallow and upper gastrointestinal (GI) endoscopy. Twenty nine (76.3%) patients improved with first dilatation, 8 (21%) patients had to undergo second dilatation and 1 (2.6%) required a third. Most of the patients remained asymptomatic during a follow-up of 6 months to 6 years. Immediate and late complications occurred in 5 (13%) and 2 (5.2%) patients, respectively. Thus, pneumatic dilatation is a simple, safe and effective method for treating Indian patients with achalasia cardia.

Adolescent↗
PubMedDate not supplied

Helicobacter pylori in gastric cancer in India.

BACKGROUND/AIMS: Helicobacter pylori infection has been implicated in pathogenesis of gastric cancer. Since there is paucity of reports from developing countries on association of H. pylori with gastric cancer, we performed case control study to find out the relationship between H. pylori and gastric cancer and also compared characteristics of gastric cancer and H. pylori positivity in younger and older patients. PATIENTS AND METHODS: Gastrectomy (n = 37) or endoscopic biopsy (n = 43) samples from area adjoining the cancer were collected from 80 patients of gastric cancer. Tissue specimens were stained with hematoxylin-eosin and Giemsa stains and histological type of cancer was determined according to Lauren, as intestinal or diffuse type. The presence of H. pylori was assessed by Giemsa staining. Eighty age and sex matched patients with non-ulcer dyspepsia (NUD) served as controls. RESULTS: Of 80 patients, 48 had intestinal type, 28 diffuse type and 4 had mixed type of gastric cancer. Tumour was located in antrum in 37, in body in 31, and at other sites in 12 cases. H. pyolri infection was present in 29 of patients compared to 36 patients with non-ulcer dyspepsia (p > 0.05, odd ratio 0.69, confidence interval 0.37-1.32). The positivity for H. pylori was higher in intestinal type than in diffuse type (p < 0.05) of gastric cancer but similar in patients with growth in antrum and body (p = NS) of stomach. There was no significant difference in tumor type, tumor site, frequency of intestinal metaplasia and H. pylori positivity (39% vs 35%, P > 0.05, odd ratio 1.19, confidence interval 0.44-3.23) in younger (< 45 yrs) and older (> 45 yrs) patients. CONCLUSIONS: Approximately one-third of patients with gastric cancer show presence of H. pylori infection on histological examination. No difference in H. pylori positivity were observed in young and old patients of gastric cancer.

Adult↗
PubMedDate not supplied

Liver span and weight in health and disease.

BACKGROUND: The liver mass, made up of independent functional units called acini, correlates with liver functions. Hepatic morphological changes causing alteration in its size and volume occur in various hepatic disorders. METHODS: Antemortem clinical liver span and postmortem liver weight was studied in 23 critically ill patients. Out of these, 8 had fulminant hepatic failure, 7 had chronic liver disease with encephalopathy and 8 had other serious illnesses (chronic renal failure 3; ischaemic heart disease 3; cerebrovascular accidents 2). We also studied postmortem liver span and liver weight in 173 healthy individuals dying of accident/terrorist attacks. RESULTS: Antemortem liver span in 23 critically ill patients was 9.9 +/- 4.7 cm (mean +/- S.D.) and postmortem liver weight was 1536.9 +/- 704.7 g (mean +/- S.D.). Antemortem liver span correlated well with the postmortem liver weight (r = 0.9635). Postmortem liver span in 173 healthy individuals was 16.3 +/- 2.7 cm (mean +/- S.D.) and liver weight was 1301.5 +/- 358.8 g (mean +/- S.D.). There was very good correlation between the postmortem liver span and liver weight (r = 0.516), height (r = 0.410) and body weight (r = 0.340) in these individuals. CONCLUSION: Liver span fortells the liver weight, hence, the functional liver mass in diseased and healthy individuals.

Case-Control Studies↗
PubMedDate not supplied

Impact of ranitidine on prognosis after simple closure of perforated duodenal ulcer.

AIM: This randomized controlled study was carried out to evaluate the role of H2 receptor antagonists after simple closure of perforated duodenal ulcer. METHODS: A total of 192 patients who underwent simple closure for perforated duodenal ulcer were divided into two groups (A: study group and B: control group). Group A patients were treated with H2 receptor antagonists, while the patients in group B received placebo. Only 174 patients were available for endoscopic follow up. RESULTS: At the end of 24 weeks, only 6 patients out of 90 (6.6%) in group A as compared to 18 patients out of 84 (21.4%) in group B had persistent symptoms of ulcer disease as well as endoscopically proven ulcer (p < 0.05). CONCLUSIONS: The results indicate that H2 receptor antagonists have a definite role and endoscopic follow up is mandatory to define those cases who actually need definitive surgery.

Adolescent↗
PubMedDate not supplied

Non-cirrhotic portal fibrosis in children.

BACKGROUND AND OBJECTIVES: Non-cirrhotic portal fibrosis (NCPF) is an infrequent cause of portal hypertension in children. We report 11 children with NCPF, from among 338 with portal hypertension, seen over 6.5 years. METHODS: The diagnosis was based on patent splenoportal axis on ultrasonography and/or splenoportal venography and liver biopsy showing no evidence of cirrhosis or other diagnosis, in children with portal hypertension. Those with variceal bleed were managed with endoscopic sclerotherapy and/or shunt surgery. RESULTS: The median age was 11 years (range 5 to 14), and 8 were boys. Presentation was with variceal bleed in 6, lump in left upper abdomen in 5 (though all children had splenomegaly) and esophageal varices on endoscopy. The median spleen enlargement was 8.5 cm; 8 also had hepatomegaly. Hypersplenism was present in 7, and two had developed ascites after bleed. Of 6 children presenting with bleed, variceal obliteration was achieved on sclerotherapy (average 5.6 sessions) in 4 while two underwent shunt surgery for associated hypersplenism. After median follow up of 57.5 months (range 12-78) all are alive and well. CONCLUSION: NCPF is an uncommon cause of portal hypertension in Indian children. Presentation with variceal bleed is less common than in adults; sclerotherapy is effective.

Adolescent↗
PubMedDate not supplied

Extended survival of carcinoma head of pancreas following palliative treatment.

A 48 year old woman presented with obstructive jaundice 10 years back. Upper gastrointestinal endoscopy revealed a growth infiltrating the ampulla of Vater, which was confirmed to be adenocarcinoma on cytology. At laparotomy, a large nodular growth was seen in the head of pancreas. Surgical resection could not be done because of encasement of superior mesenteric vessels, hence a cholecystojejunostomy was performed. The patient remained asymptomatic for 9 years, when she developed cholangitis. Duodenoscopy at this stage revealed an ulcerated growth at the ampulla and biopsy from the growth confirmed a well differentiated adenocarcinoma. A straight flap 10 F stent was placed in the common bile duct. Thereafter the patient has remained asymptomatic for more than a year.

Adenocarcinoma↗
PubMedDate not supplied

Intestinal pseudo-obstruction due to neurofibromatosis responding to cisapride.

Gastrointestinal involvement in neurofibromatosis presenting with mechanical obstruction, hemorrhage or intussusception is known. Small bowel dysmotility and intestinal pseudo-obstruction due to neurofibromatosis is rare. A 23-year-old man with classical neurofibromatosis presented with intermittent episodes of intestinal pseudo-obstruction, small bowel bacterial overgrowth and steatorrhea. The patient had good symptomatic improvement with cisapride.

Adult↗
PubMedDate not supplied

Enteropathogenic Escherichia coli isolates in paediatric diarrhoea.

Enteropathogenic Escherichia coli (EPEC) are known to cause infantile enteritis. We studied the prevalence of EPEC in paediatric patients with acute and persistent diarrhoea. A total of 56 stool samples from paediatric patients were studied. There were 28 significant bacterial isolates. Of these 21 were untypable E. coli, 5 were typable E. coli, four of which belonged to members considered to be enteropathogenic. Non E. coli isolates grown in pure culture were one each of Pseudomonas aeruginosa and Citrobacter freundi. The study reveals the definitive role of EPEC in childhood diarrhoea at all age groups and emphasizes the need for characterisation of all significant E. coli isolates in this age group.

Child↗
PubMedDate not supplied

Pleural involvement by Salmonella senftenberg: a report of two cases.

Non-typhoidal serovars of salmonella are an unusual cause of pleuropulmonary infections. We report two patients with empyema caused by Salmonella senftenberg. One patient had associated diabetes and gall bladder carcinoma, and infection was acquired in hospital. Both patients responded well to parenteral antibiotics.

Anti-Bacterial Agents↗
PubMedDate not supplied

Helicobacter pylori infection in chronic smokers with non ulcer dyspepsia.

BACKGROUND/AIMS: Both H. pylori infection and smoking are risk factors for acid peptic disorders. There is paucity of data on relationship between smoking and H. pylori infection. Therefore, we studied prevalence of H. pylori infection in smokers with non-ulcer dyspepsia (NUD). PATIENTS AND METHODS: 30 smokers with NUD (age 29.5 +/- 1.2 years; all men) and 30 non-smokers with NUD (age 29.2 +/- 1.6 years; all men) were included. None was on antiulcer drugs or antibiotics for more than 2 weeks. Upper gastrointestinal endoscopy was performed and antral biopsies obtained were subjected to rapid urease test, Gram's staining, culture and histopathology. Patient was considered H. pylori positive, if culture was positive or combination of histopathology plus rapid urease test or Gram's staining plus rapid urease test was positive. RESULTS: 24 of 30 (80%) smokers and 13 of 30 (43%) non smokers were positive for H. pylori infection (p < 0.001). There was no significant difference in the positivity of H. pylori in light (78%), moderate (81%) and heavy smokers (80%). All the 37 patients who were positive for H. pylori had histological gastritis compared to 65% in H. pylori negative patients. However there was no difference in presence of histological gastritis among H. pylori negative smokers (33%) and non smokers (70%; p = NS). CONCLUSIONS: H. pylori infection is more common in smokers with NUD than in non-smokers. However duration and amount of smoking has no relationship with H. pylori positivity.

Adult↗