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Biomedical subjects

K Singh

Publications and source records attributed to K Singh.

At least 181 records · Page 10Linked to original sources

Helicobacter pylori: evidence for spouse-to-spouse transmission.

BACKGROUND: Spouse-to-spouse transmission of Helicobacter pylori infection still remains controversial. METHODS: We studied the prevalence of H. pylori infection among spouses of H. pylori-positive or -negative individuals and looked for intraspousal transmission. Twenty-five couples were studied. Initially, one individual per couple was selected as the index subject. Spouses of these H. pylori-positive or -negative index individuals underwent screening for H. pylori by serology, the rapid urease test and histology. Those couples in whom only one spouse was positive were followed up and H. pylori status was re-evaluated using the above tests after approximately 1 year in the H. pylori-negative spouse. RESULTS: Of 25 randomly selected index subjects, 18 were H. pylori positive and seven were negative. There was no significant difference in age, sex, socioeconomic status, presence of dyspeptic symptoms, duration of marriage and number of children in these index subjects. Spouses of H. pylori-infected index subjects had a significantly higher prevalence of H. pylori infection than the spouses of H. pylori-negative index subjects (83.3 vs 28.5%; P < 0.01). Age, sex, socioeconomic status, dyspeptic symptoms, duration of marriage and number of children were not different in H. pylori-positive or -negative spouses of H. pylori-positive index subjects. There were five such couples in whom only one spouse was H. pylori positive initially. At follow up, three of these H. pylori-negative spouses became positive. These findings suggest person-to-person transmission or common source exposure within couples.

Adult↗

Effect of rotavirus infection on small gut pathophysiology in a mouse model.

AIM: To study the effect of rotavirus infection on amino acid uptake in the small intestine in an experimental mouse model. METHODS: Infant mice (7-8 days of age) were orally infected with the EB serotype 3 strain of rotavirus and animals (both infected and control) were killed on days 0, 1, 3, 5, 7 and 10 post inoculation (PI) after recording their bodyweights. Gamma-glutamyltranspeptidase (GGT), leucine amino peptidase (LAP), glutathione (GSH) and leucine amino acid uptake in the jejunum and ileum were assessed. RESULTS: Infected animals showed significant reduction in their bodyweights and intestinal lengths on the third day PI compared with controls. Leucine amino peptidase, GGT, GSH and leucine uptake were significantly reduced in the ileum on the third and fifth day PI compared with controls while uptake in the jejunum was only reduced on third day PI. The LAP, GGTP, GSH and leucine uptake attained normal levels on the seventh day when diarrhoea stopped. Histology showed damage to the villi in the jejunum and prominent cytoplasmic vacuolation in the ileum of infected animals on the third and fifth day PI. CONCLUSION: Rotavirus affects amino acid uptake in the small intestine at the time of peak infection.

Animals↗

Congenital hepatic fibrosis in Indian children.

BACKGROUND: Congenital hepatic fibrosis (CHF) is an uncommon cause of portal hypertension in children. So far, there is no report of this from the subcontinent. We have studied the clinical spectrum of CHF in North Indian children. METHODS: Fifteen children were diagnosed with CHF on the basis of their liver histology over a period of 6.5 years. Their clinical details were recorded. Oesophagogastroduodenoscopy and abdominal ultrasonography were performed in all cases. All siblings were examined clinically; and ultrasonography, endoscopy and liver biopsy were performed if there was firm hepatomegaly. Children with variceal bleeding were managed by endoscopic sclerotherapy. The median age of these children was 8 years with a male to female ratio of 1.5:1. RESULTS: Only one sibling (of 33) was diagnosed as having CHF. The predominant presentations were variceal bleeding in six, abdominal distension in seven and incidental detection of organomegaly in two. Hepatomegaly was present in all patients and splenomegaly in all but one. Liver function and renal function tests were normal in all children, except for a raised serum alkaline phosphatase in six. Two children had associated renal cysts, two had choledochal cysts, one each had Caroli's disease and biliary atresia and two children had portal vein thrombosis. Variceal obliteration was achieved in five children after an average 4.8 sclerotherapy sessions and one required a mesocaval shunt. On follow up (median 41 months, range 1-80 months) all are doing well. CONCLUSIONS: Congenital hepatic fibrosis is mainly sporadic in India and associated renal lesions are uncommon. Endoscopic sclerotherapy is effective in controlling variceal bleed and the prognosis is universally good in the absence of renal diseases.

Adolescent↗

Does an acidic medium enhance the efficacy of vaginal misoprostol for pre-abortion cervical priming?

Absorption pharmacokinetics reveal a relationship between plasma concentrations of misoprostol and its therapeutic effect. To achieve a constant plasma profile and optimal efficacy, it is important to develop a medium that ensures complete dissolution of vaginal misoprostol tablets. Vaginal misoprostol is said to liquefy better in an acidic medium; thus, the aim of this study was to determine whether a 200 microg misoprostol tablet dissolved in acetic acid would be more efficacious than 200 microg misoprostol dissolved in water for pre-abortion cervical priming. A total of 120 healthy nulliparous women requesting legal termination of pregnancy between 6-12 weeks gestation were allocated randomly to either of the study groups. Vacuum aspiration was performed 3-4 h after insertion of the misoprostol tablet. Using Hegar's dilator, the degree of cervical dilatation before operation was measured. Of 60 women, 14 (23%) achieved a cervical dilatation of >/=8 mm when the misoprostol dose was dissolved in acetic acid; 12 (20%) achieved a similar cervical dilatation when the dose was dissolved in water. The mean cervical dilatation for the acid and water media used was 6.3 mm and 6.2 mm respectively; these differences were not statistically significant, neither were pre-operative and intra-operative blood losses statistically different between the two groups. Twenty-four (40%) and four (7%) respectively of women in whom a water medium was used experienced vaginal bleeding and abdominal pain; 20 (33%) and 0 women respectively among those in whom an acetic acid medium was used experienced vaginal bleeding and abdominal pain. These differences in side effects were not statistically significant. Our study shows that the use of acetic acid to dissolve vaginal misoprostol does not improve the efficacy in achieving successful cervical dilatation for pre-abortion cervical priming.

Abortifacient Agents, Nonsteroidal↗

Epidemic dropsy in the eastern region of Nepal.

Twenty-six persons from five families comprising 34 members residing in different areas of Saptari district of the eastern region of Nepal developed symptoms of epidemic dropsy over 6-8 weeks. Seventeen patients were studied during July-August 1996. The age of affected individuals varied from 3 to 75 years. Members who had not consumed food cooked in mustard oil or who were not residing with the family were spared. Mustard oil, which was used for cooking, was found to be contaminated with oil of Argemone mexicana seeds. Sanguinarine was detected in all mustard oil samples collected from the homes of affected families. Gastrointestinal symptoms were present in 82 per cent of cases a week or so prior to the onset of pedal oedema. Pitting oedema of the lower limbs, fever, and darkening of the skin were the most consistent features, found in all cases. Other prominent features such as local erythema (82 per cent) and tenderness (88 per cent) of the lower limbs were present in most cases. Two striking features not previously noted were perianal itching (100 per cent) and severe carditis (35 per cent) with congestive cardiac failure (29 per cent). Other unique features noted were 'sarcoid' skin changes (18 per cent), bilateral pleural effusion, and Roth's spots and subhyloid haemorrhages in the fundus in one patient. Other important findings were anaemia (88 per cent), hepatomegaly (41 per cent), pneumonia (35 per cent) and ascites (12 per cent). There were no deaths due to epidemic dropsy. In the majority of cases, oedema, cutaneous changes, and carditis showed a marked improvement in 2-3 weeks and patients were well after 6-8 weeks of follow-up.

Adolescent↗

Clinical and laboratory study of kala-azar in children in Nepal.

Reports are scanty regarding kala-azar in children in Nepal. In this communication we document 20 children diagnosed to have kala-azar who were admitted and treated at B. P. Koirala Institute of Health Sciences, Dharan, Nepal. The children were between 2 and 14 years old. The duration of illness varied between 12 days and 24 months with a majority (65 per cent) of children being ill for less than 6 months. Hepatomegaly and splenomegaly were seen in 95 and 90 per cent of cases respectively. Splenomegaly was not found in two (10 per cent) children. Anaemia, leucopenia, and thrombocytopenia were seen in 95, 60, and 75 per cent of children respectively. Amastigotes of Leishmania donovani (LD bodies) were demonstrated in Giemsa-stained smears of bone marrow aspirates in 16 (80 per cent) children. All the children responded to treatment with sodium stibogluconate. No mortality was observed. This study emphasizes the importance of kala-azar in children in endemic areas of eastern Nepal.

Adolescent↗

Helicobacter pylori eradication: comparison of three treatment regimens in India.

Conventional bismuth-based triple therapy has multiple problems, such as inadequate drug compliance, side effects, and drug resistance. Combination of omeprazole and clarithromycin with or without combination with antibiotics like amoxycillin has been shown to be effective in eradication of Helicobacter pylori. Reports from India are few on the efficacy of clarithromycin-based drug combinations. Therefore, we evaluated efficacy of omeprazole and clarithromycin with or without amoxycillin for treating H. pylori infection. Sixty-four consecutive patients with upper gastrointestinal symptoms and having H. pylori infection were included. In every patient, complete upper gastrointestinal endoscopy was done. H. pylori infection was diagnosed by identification of organism on antral biopsies and positive rapid urease test. Patients were treated with omeprazole 40 mg/day + clarithromycin 250 mg twice daily (group I, n = 22), or omeprazole 40 mg/day + clarithromycin 250 mg twice daily + amoxycillin 500 mg three times daily (group II, n = 20), or bismuth subcitrate 120 mg four times daily + amoxycillin 500 mg three times daily + metronidazole 400 mg three times daily (group III, n = 22) for 2 weeks. H. pylori status was reevaluated 1 month after completion of treatment. One patient in each group stopped drugs due to side effects. Eradication rate was not significantly different in group I (15/22, 68%), group II (14/20, 70%), and group III (13/22, 59%). Of those completing therapy, side effects were observed in three patients in group III (nausea, skin rash, metallic taste), whereas none of the patients in group I and group II had any side effects. Addition of amoxycillin did not appear to improve efficacy of dual omeprazole and clarithromycin therapy and appeared to be no different than bismuth, metronidazole, and amoxycillin triple therapy. Overall, none of regimens was particularly good.

Adolescent↗

Previous cesarean section and abortion as risk factors for developing placenta previa.

OBJECTIVE: To determine the risk of subsequent occurrence of placenta previa in women with a history of previous cesarean sections and/or spontaneous and induced abortions. METHODS: A retrospective analysis of all single gestation deliveries at National University Hospital of Singapore from 1993-1997 was done. Women with placenta previa were identified by clinical or ultrasonographic diagnosis. RESULTS: Of the 16,169 singleton deliveries, 164 women (1.0%) had placenta previa. Women with placenta previa had a significantly higher incidence of previous cesarean sections (p < 0.001). Among the 164 women with placenta previa, women with 1, 2, and 3 previous cesarean sections had 2.2 (95% CI 1.4, 3.4), 4.1 (95% CI 1.9, 8.8) and 22.4 (95% CI 6.4, 78.3) times increased risk of developing placenta previa respectively. Similarly, women with 2 or more previous abortions had a 2.1 (95% CI 1.2, 3.5) times increased risk of subsequently developing placenta previa. CONCLUSION: There is a strong association between previous cesarean section and risk of subsequent development of placenta previa. This risk increased with the number of previous cesarean sections. Increasing frequency of abortions was also found to predispose a woman to placenta previa.

Abortion, Induced↗

Vaginal misoprostol for pre-abortion cervical priming: is there an optimal evacuation time interval?

OBJECTIVE: To determine the optimal evacuation time interval in the use of vaginal misoprostol for cervical priming before first trimester termination of pregnancy. DESIGN: Prospective double-blind randomised study. SETTING: Fertility Control Centre, National University Hospital, Singapore. METHODS: Sixty healthy nulliparous women requesting legal termination of pregnancy between 6 and 11 weeks of gestation were randomly allocated to either the 400 microg or 600 microg misoprostol group. Vacuum aspiration was performed after three hours in the 400 microg group and at the end of two hours in the women given 600 microg misoprostol. Using Hegar's dilator, degree of cervical dilatation before operation was measured. Other parameters assessed included the amount of additional dilatation required (if < Hegar 8), pre-operative and intra-operative blood loss, and associated side effects. RESULTS: For the 600 microg group, only five women (16.7%) achieved a cervical dilatation of > or = 8 mm, compared with 28 women (93.3%) in the 400 microg group. Using the 400 microg misoprostol group as a baseline, the odds ratio was 0.014 (95% CI 0.003-0.080) for 600 microg for successful pre-operative cervical dilatation of > or = 8 mm. The mean cervical dilatation for 400 and 600 microg misoprostol was 8.1 mm and 6.6 mm, respectively (P < 0.001). Despite the shorter evacuation time interval of two hours, the 600 microg dose was associated with an increase in side effects such as vaginal bleeding, abdominal pain and a fever of > 38.0 degrees C. However, other than abdominal pain, no significant differences in the frequency of these side effects were shown. CONCLUSION: Use of 400 microg misoprostol with a minimal evacuation time interval of three hours still appears the optimal dosage and evacuation time for cervical priming before first trimester termination of pregnancy.

Abortifacient Agents, Nonsteroidal↗

Endoscopic management of bleeding ectopic varices with histoacryl.

Bleeding from antral and duodenal varices is an uncommon feature in patients with portal hypertension. We report a patient with cirrhosis and portal vein thrombosis, who had a massive bleed from antral and duodenal varices. Bleeding was controlled with endoscopic injection of varices using histoacryl. Endoscopic treatment and the relatively uncommon occurrence of antral and duodenal varices are highlighted.

Duodenal Diseases↗

Protective efficacy of trypsin inhibitor on the the gut following rotavirus infection in malnourished infant mice.

Epidemiologic data suggest a close relationship between protein energy malnutrition (or protein energy malnourished) (PEM) and development of infectious diarrheal diseases. In the present studies, the impact of trypsin inhibitor (TI) on the gut following rotavirus (RV) infection was investigated in PEM young growing inbred balb/c mice. The animals were divided into four groups: (1) control; (2) PEM; (3) PEM+RV and (4) PEM+ RV+TI. Control and PEM animals were orally inoculated with normal saline, PEM+RV animals were given 50 microl RV (100ID50) and PEM+RV+TI animals were inoculated with 0.6 mg TI/g body weight + 50 micronl RV. The body weight of each animal was recorded. Six animals from each group were sacrificed on days 0, 1, 3, 5, 7 and 10 post inoculation by cervical dislocation. The intestines were removed, everted and homogenized in ice-cold saline. Leucine aminopeptidase (LAP), glutathione (GSH) levels and L-leucine uptake were determined in the jejunum and ileum. Body weight was decreased in PEM and PEM+RV groups compared to the controls. LAP and leucine uptake levels were elevated in the PEM group but decreased in the PEM+RV group. GSH levels were decreased in the PEM+RV group. Enzyme activity, GSH and LAP uptake levels were restored in the PEM+RV+TI group. The study shows the protective role of soybean TI against RV infection in malnourished mice.

Animals↗

Direct effects of colchicine on myocardial function: studies in hypertrophied and failing spontaneously hypertensive rats.

-The aging spontaneously hypertensive rat (SHR) is a model in which the transition from chronic stable left ventricular hypertrophy to overt heart failure can be observed. Although the mechanisms for impaired function in hypertrophied and failing cardiac muscle from the SHR have been studied, none accounts fully for the myocardial contractile abnormalities. The cardiac cytoskeleton has been implicated as a possible cause for myocardial dysfunction. If an increase in microtubules contributes to dysfunction, then myocardial microtubule disruption by colchicine should promote an improvement in cardiac performance. We studied the active and passive properties of isolated left ventricular papillary muscles from 18- to 24-month-old SHR with evidence of heart failure (SHR-F, n=6), age-matched SHR without heart failure (SHR-NF, n=6), and age-matched normotensive Wistar-Kyoto rats (WKY, n=5). Mechanical parameters were analyzed before and up to 90 minutes after the addition of colchicine (10(-5), 10(-4), and 10(-3) mol/L). In the baseline state, active tension (AT) developed by papillary muscles from the WKY group was greater than for SHR-NF and SHR-F groups (WKY 5.69+/-1.47 g/mm2 [mean+/-SD], SHR-NF 3.41+/-1.05, SHR-F 2.87+/-0.26; SHR-NF and SHR-F P<0.05 versus WKY rats). The passive stiffness was greater in SHR-F than in the WKY and SHR-NF groups (central segment exponential stiffness constant, Kcs: SHR-F 70+/-25, SHR-NF 44+/-17, WKY 41+/-13 [mean+/-SD]; SHR-F P<0.05 versus SHR-NF and WKY rats). AT did not improve after 10, 20, and 30 minutes of exposure to colchicine (10(-5), 10(-4), and 10(-3) mol/L) in any group. In the SHR-F group, AT and passive stiffness did not change after 30 to 90 minutes of colchicine exposure (10(-4) mol/L). In summary, the data in this study fail to demonstrate improvement of intrinsic muscle function in SHR with heart failure after colchicine. Thus, in the SHR there is no evidence that colchicine-induced cardiac microtubular depolymerization affects the active or passive properties of hypertrophied or failing left ventricular myocardium.

Animals↗

Myocardial osteopontin expression coincides with the development of heart failure.

To identify genes that are differentially expressed during the transition from compensated hypertrophy to failure, myocardial mRNA from spontaneously hypertensive rats (SHR) with heart failure (SHR-F) was compared with that from age-matched SHR with compensated hypertrophy (SHR-NF) and normotensive Wistar-Kyoto rats (WKY) by differential display reverse transcriptase-polymerase chain reaction. Characterization of a transcript differentially expressed in SHR-F yielded a cDNA with homology to the extracellular matrix protein osteopontin. Northern analysis showed low levels of osteopontin mRNA in left ventricular myocardium from WKY and SHR-NF but a markedly increased (approximately 10-fold) level in SHR-F. In myocardium from WKY and SHR-NF, in situ hybridization showed only scant osteopontin mRNA, primarily in arteriolar cells. In SHR-F, in situ hybridization revealed abundant expression of osteopontin mRNA, primarily in nonmyocytes in the interstitial and perivascular space. Similar findings for osteopontin protein were observed in the midwall region of myocardium from the SHR-F group. Consistent with the findings in SHR, osteopontin mRNA was minimally increased (approximately 1.9-fold) in left ventricular myocardium from nonfailing aortic-banded rats with pressure-overload hypertrophy but was markedly increased (approximately 8-fold) in banded rats with failure. Treatment with captopril starting before or after the onset of failure in the SHR reduced the increase in left ventricular osteopontin mRNA levels. Thus, osteopontin expression is markedly increased in the heart coincident with the development of heart failure. The source of osteopontin in SHR-F is primarily nonmyocytes, and its induction is inhibited by an angiotensin-converting enzyme inhibitor, suggesting a role for angiotensin II. Given the known biological activities of osteopontin, including cell adhesion and regulation of inducible nitric oxide synthase gene expression, these data suggest that it could play a role in the pathophysiology of heart failure.

Animals↗

Comparison of phacotrabeculectomy with 5-fluorouracil, mitomycin-C, and without antifibrotic agents.

BACKGROUND AND OBJECTIVE: To evaluate the potential benefits, complications, and prognostic risk factors for failure of phacotrabeculectomy performed with or without 5-fluorouracil (5-FU) and mitomycin-C (MMC). PATIENTS AND METHODS: Retrospective chart review of 78 patients who underwent phacotrabeculectomy during a 2-year period. Patients were divided into 3 groups, those who received 5-FU (N = 28). MMC (N = 29), or no antifibrotic agent (N = 21). RESULTS: All 3 groups had statistically significant lower intraocular pressures (IOP) on fewer antiglaucomatous medications at 6-month, 12-month, and last follow-up compared to preoperative levels (P < .05). Intraocular pressures were lower in the group that received MMC compared to the 5-FU group, but not in the group that did not receive antimetabolites, at all time intervals measured (P < .05). Black race was a strong predictor of failure of trabeculectomy (P = 009). No differences in final visual acuity or complications were found between groups. CONCLUSIONS: Phacotrabeculectomy is effective regardless of antimetabolite use. Race is a strong predictor of failure.

Aged↗

Yeast colonisation & fungaemia in preterm neonates in a tertiary care centre.

Seventy consecutive preterm neonates who stayed in the hospital for more than seven days between March and October 1996, were studied for colonisation at oral, umbilical, groin, and rectal areas and for fungaemia. Overall, 71.4 per cent of the neonates were colonised and colonisation occurred within 24 h in 38 per cent preterm neonates. Neonates weighing less than 1500 g were colonised more frequently at more than one site and had higher load of yeast. Candida albicans (19%), Pichia (Hansenula) anomala (17.5%), C. tropicalis (13.2%), C. parapsilosis (12.3%) and Trichosporon cutaneum (10.0%) were the predominant colonising yeasts. Fungaemia was detected in 22.8 per cent of preterm neonates with predominance of P. anomala fungaemia (62.5%). Prematurity, male sex, broad spectrum antibiotic therapy, intubation and higher colonising rate were identified as significant risk factors for development of fungaemia. Except one strain of C. tropicalis, all yeast strains were sensitive to commonly used systemic antifungal agents. Study highlights the importance of routine surveillance of yeast colonisation of preterm neonates with identifying possible risk factors.

Anti-Bacterial Agents↗