Biomedical subjects

S Ghosh

Publications and source records attributed to S Ghosh.

At least 127 records · Page 7Linked to original sources

PubMed2003

Cholangiocarcinoma presenting with recurrent venous thrombosis.

A 38 years female presented with three episodes of venous thrombosis over one year--first in left femoral vein, next in splenic vein causing haematemesis and malena and lastly in inferior vena cava causing Budd-Chiari syndrome. During third episode, endoscopic cholangiopancreatography and guided biopsy established a diagnosis of cholangiocarcinoma at the mid portion of common bile duct. The disease was far advanced with cervical lymph node metastasis.

Adult↗

PubMed2002

Coherent spin oscillations in a disordered magnet.

Most materials freeze when cooled to sufficiently low temperature. We find that magnetic dipoles randomly distributed in a solid matrix condense into a spin liquid with spectral properties on cooling that are the diametric opposite of those for conventional glasses. Measurements of the nonlinear magnetic dynamics in the low-temperature liquid reveal the presence of coherent spin oscillations composed of hundreds of spins with lifetimes of up to 10 seconds. These excitations can be labeled by frequency and manipulated by the magnetic fields from a loop of wire and can permit the encoding of information at multiple frequencies simultaneously.

Journal Article↗

PubMed2002

Raman coherence beats from entangled polarization eigenstates in InAs quantum dots.

The homodyne-detected transient four-wave-mixing response of InAs/GaAs self-assembled quantum dots shows temporal oscillations of the optically induced Raman coherence arising from two entangled polarization eigenstates of the exciton. The phase sensitive nature of the homodyne detection enables us to follow the time evolution of the nonradiative quantum coherence between the polarization states, providing a measurement of the fine-structure splitting in the dots, which is much less than the inhomogeneous broadening, and the corresponding decoherence rate of the entangled state.

Journal Article↗

PubMed2002

Assessment of ileoanal pouch inflammation by interleukin 1beta and interleukin 8 concentrations in the gut lumen.

PURPOSE: The cytokines interleukin 1beta and interleukin 8 have previously been shown to be present in mucosal biopsy specimens from inflamed ileoanal pouches. Our aim was to use the method of whole gut lavage fluid to measure cytokine concentrations and relate these to disease activity. METHODS: Forty-two patients with ulcerative colitis were recruited (23 males). Their ages ranged from 20 to 73 years (median 39). A questionnaire was completed and whole gut lavage, pouchoscopy, and biopsy were performed. RESULTS: Both interleukin 1beta and interleukin 8 were present in the whole gut lavage fluid of ileoanal pouches, with concentrations ranging from 4 to 143 pg/ml (median 6.3 pg/ml) for whole gut lavage fluid interleukin 1beta and from 18 to 1000 pg/ml (median 53.7 pg/ml) for whole gut lavage fluid interleukin 8. Whole gut lavage fluid interleukin 1beta and interleukin 8 were simultaneously detectable in 24 patients. These included the five patients with pouchitis, who had higher levels of interleukin 1beta (75 pg/ml vs. 8 pg/ml, P < 0.005) and interleukin 8 (668 pg/ml vs. 106 pg/ml, P < 0.005) compared with the rest of the patients with detectable cytokines (n = 19). The sensitivity of whole gut lavage fluid interleukin 8 (>200 pg/ml) in the diagnosis of pouchitis was 1, and the specificity was 0.86. There was a significant positive correlation of both whole gut lavage fluid interleukin 1beta and interleukin 8 with all the gut protein loss markers (immunoglobulin G, albumin, alpha1-antitrypsin). CONCLUSION: Cytokine interleukin 1beta and interleukin 8 concentrations, along with other parameters of inflammation, are raised in pouchitis in the whole gut lavage. The results also suggest a spectrum of severity of "pouchitis," with clinical pouchitis fulfilling Moskowitz criteria at the severe end of the spectrum.

Adult↗

PubMed2002

The radial hyperaemic response: a new and objective assessment of ulnar collateral supply to the hand.

The assessment of adequate ulnar collateral supply to the hand is mandatory prior to the harvest of the radial artery as a conduit for coronary artery bypass grafting. However, there is currently no one test which is widely used in all centres. We report a new and objective method of assessing ulnar collateral supply to the hand prior to harvest of the radial artery. This technique involves assessing the presence of a hyperaemic flow response to occlusion of the radial artery using an intraoperative transit time flowmeter. We found this technique to be objective and reliable, and would advocate its use in patients with a positive Allen's test.

Collateral Circulation↗

PubMed2002

Risk factors for intestinal ischaemia in cardiac surgical patients.

OBJECTIVE: Mesenteric ischaemia is an uncommon (<1%) but serious complication of cardiac surgery associated with a mortality >50%. Predictors of this complication are not well defined, and diagnosis can be difficult and prompt surgical intervention can be lifesaving. METHODS AND RESULTS: In a retrospective case-note analysis from May 1994 through to May 2000, we identified mesenteric ischaemia in 39 of 5349 consecutive patients (0.07%) undergoing cardiac surgery with cardiopulmonary bypass. By logistic multivariate analysis, we have identified six possible predictors of intestinal ischaemia: duration of cross-clamp, use of significant inotropic support, intra-aortic balloon counterpulsation for low cardiac output, need for blood transfusions, triple vessel disease and peripheral vascular disease. In all patients a combination of four predictors were present. Patients who survived this complication had surgical intervention earlier (6.4+/-3.8 h) than those who did not (16.9+/-10 h). CONCLUSIONS: The diagnosis and prompt treatment of mesenteric ischaemia post cardiac surgery requires a high degree of awareness. These predictors may be useful in alerting medical staff to the possibility of gastro-intestinal ischaemic complications after cardiac surgery particularly that early surgical intervention reduces mortality.

Cardiac Surgical Procedures↗

PubMed2002

Whole gut lavage fluid interleukin-1beta and interleukin-8 in smokers and non-smokers with Crohn's disease in clinical remission.

INTRODUCTION: Smoking in patients with Crohn's disease is associated with more frequent relapse. The mechanism responsible is unknown but a direct pro-inflammatory action on intestinal mucosa has been postulated. Mucosal inflammation in clinically inactive Crohn's disease predicts forthcoming relapse. Whole gut lavage fluid obtained after bowel cleansing with a polyethylene glycol electrolyte solution is an assessment of gut inflammation and immunity. AIM: To assess whether whole gut lavage fluid interleukin-1beta and interleukin-8 differed between smokers and non-smokers with clinically inactive Crohn's disease. METHODS: A total of 34 patients with inactive Crohn's disease (Crohn's disease activity index <150 and whole gut lavage fluid IgG concentration of <10 mg/ml) underwent whole gut lavage with interleukin-1beta and interleukin-8 analysed by enzyme-linked immunosorbent assay. Clinical details and blood markers of inflammation were collected. RESULTS: In this series, 14 patients smoked (10 females, mean age 44.3+/-14.3 years), 20 did not (12 females, mean age 40.7+/-14.3). Surgical resection was more common in smokers (12/14 vs 8/20, p<0.008). Whole gut lavage fluid IgG was significantly lower in smokers (median 1.5 mg/ml (range 1.0-8.0 mg/ml) vs median 3.5 mg/ml (range 1.0-7.0 mg/ml), p<0.05). Whole gut lavage fluid interleukin-1beta was also lower in smokers [median 14.5 pg/ml (range 2-72 pg/ml) vs 26 pg/ml (range 7-1700 pg/ml)], p<0.03. CONCLUSION: Markers of mucosal inflammation in inactive Crohn's disease are lower in smokers than non-smokers. This is against the hypothesis that nicotine exerts a direct pro-inflammatory action via interleukin-1beta and interleukin-8. Further research is required to elucidate the exact mechanisms involved.

Adult↗

PubMed2002

Anti-inflammatory effects of enteral diet components on Crohn's disease-affected tissues in vitro.

BACKGROUND: The mechanism of action of elemental diet in Crohn's disease treatment, is unknown. Alteration of bacterial flora, low antigenicity, low fat content and improvement of nutritional status are postulated to play a role in the anti-inflammatory effect of elemental diet. AIM: To determine whether elemental diet or its modifications has a direct anti-inflammatory effect on colonic tissue biopsies in vitro. PATIENTS AND METHODS: Colonic or ileal biopsies from 39 patients with inflammatory bowel disease and control patients were incubated for 24 hours with enteral diets in which nitrogen sources were amino acids as in elemental diet, casein or whey. Tissues were incubated with elemental diet, casein or whey, at dilutions of 1:5, 1:10 or 1:20 in Waymouth's complete medium; a medium control was also included. Tissue viability was assessed by bromodeoxyuridine uptake. Interleukin-1beta, interleukin-1 receptor antagonist and interleukin-10 concentrations in supernatants were measured by immunoassay (enzyme-linked immunosorbent assay). RESULTS: Incubation of tissues from Crohn's disease with elemental diet resulted in an increase in the ratio of interleukin-1 receptor antagonist/interleukin-1beta vs control statistically significant at 1:10 (89.6+/-17 vs 45.7+/-9. 1, p<0.05). Incubation of Crohn's tissue with casein resulted in a significant increase of interleukin-1 receptor antagonist/interleukin-1beta ratio at dilutions 1:20, 1:10 and 1:5 (101.8+/-22.0, p=0.05, 142.8+/-24.6, p<0.05; 109.7+/-25.0, p=0.05). In ulcerative colitis tissue and non-inflamed non-inflammatory bowel disease control tissue, no significant increase in interleukin 1 receptor antagonist/interleukin-1beta ratio was seen after incubation with elemental diet, casein and whey. CONCLUSION: Elemental diet incubation increases anti-inflammatory:proinflammatory cytokine ratio in Crohn's disease and this anti-inflammatory effect is not specifically due to amino acid composition, as diets containing casein have similar anti-inflammatory effects.

Adolescent↗

PubMed2002

Radiological insertion of gastrostomy in patients in whom endoscopy was unsuccessful.

INTRODUCTION: Endoscopy is the standard technique of percutaneous gastrostomy placement, but failure of placement may occur due to difficulty with intubation or previous abdominal surgery. A review of personal experience is made. PATIENTS AND METHODS: Between January 1997 and May 1998, 90 gastrostomy devices were successfully placed endoscopically in our unit. Endoscopic placement was unsuccessful in 3 patients and not attempted in a further 7 because of oro-pharyngeal obstruction. These 10 patients (6 male, 4 female, aged 51-84 years) had advanced neuro-degenerative disease or malignancy of the head and neck or oesophagus. All patients underwent radiological insertion of a gastrostomy tube by the 'push' method after insufflation of air into the stomach via a naso-gastric tube. RESULTS: Radiological insertion of gastrostomy device was successful in 9 out of 10 patients. Failure occurred in 1 patient due to inability to pass a naso-gastric tube and surgical gastrostomy was required. Pain at the gastrostomy site was the most common problem post-procedure and 4 patients still required analgesia on discharge. One patient developed a wound infection. There were no procedure-related deaths. The 30-day mortality due to all causes was 20%. Only 1 patient remained alive at 6 months. DISCUSSION: Availability of a radiologist trained in the placement of percutaneous gastrostomy allowed 99% of such devices to be placed percutaneously, even in those patients in whom endoscopy was not possible. However advanced underlying disease in this patient group results in a high mortality.

Aged↗

PubMed2002

Integrating sibship data for mapping quantitative trait loci.

Sibship methods have been shown to be more powerful than traditional sib-pair methods in mapping quantative trait loci. We propose a statistical procedure which integrates data on sibships into a so-called 'contrast function', a natural extension of the classical squared sib-pair trait difference proposed by Haseman & Elston (1972). We also develop a combined mean and contrast function which provides more information on linkage compared to the contrast function. Our method is extended to multiple, epistatically interacting trait loci. Monte-Carlo simulations are included to compare the efficiencies of the proposed procedures with some currently used methods. An application of our proposed method is presented using data on alcohol dependence.

Alcoholism↗

PubMed2002

Linkage mapping of quantitative trait loci in humans: an overview.

In this article, we provide an overview of the different statistical procedures that have been developed for linkage mapping of quantitative trait loci. We outline the model assumptions, the data requirements and the underlying tests for linkage for the different methods.

Chromosome Mapping↗

PubMed2002

Relevance of thiopurine methyltransferase activity in inflammatory bowel disease patients maintained on low-dose azathioprine.

BACKGROUND: It is well-recognized that patients with low thiopurine methyltransferase activity are more susceptible to the development of bone marrow suppression side-effects. AIM: To study the impact of thiopurine methyltransferase activity on the clinical course of inflammatory bowel disease patients treated with low-dose azathioprine (< 2 mg/kg). METHODS: We measured the thiopurine methyltransferase activity of blood samples from 113 inflammatory bowel disease patients who were taking azathiopurine, had discontinued azathioprine because of side-effects, or had never taken azathioprine. The thiopurine methyltransferase activity was compared with that of 17 healthy controls. Relapse rates and time to first relapse were compared in inflammatory bowel disease patients and stratified according to their thiopurine methyltransferase activity. RESULTS: Patients who became neutropenic had a significantly lower mean thiopurine methyltransferase activity than that of patients who developed other side-effects (analysis of variance, P < 0.05). Survival curves were constructed (time to first relapse) for patients treated with low-dose azathioprine for thiopurine methyltransferase activities of < 20 and > 20 nmol/mL red blood cells/h. There was a significantly lower number of relapses in inflammatory bowel disease patients with lower thiopurine methyltransferase levels (P < 0.05). CONCLUSIONS: The mean thiopurine methyltransferase activity was significantly lower in patients on a low dose of azathioprine in remission compared with those who relapsed. The thiopurine methyltransferase activity was significantly lower in patients who discontinued azathioprine due to neutropenia than in those who discontinued due to other side-effects.

Adolescent↗

PubMed2002

Review article: is clinical remission the optimum therapeutic goal in the treatment of Crohn's disease?

Currently, the therapeutic end-point in the treatment of Crohn's disease is the remission of symptoms, but recent data confirm that mucosal inflammation may continue in the absence of symptoms. Furthermore, emerging evidence indicates that such subtle, sub-clinical mucosal inflammation leads to clinical relapse. The assessment of mucosal inflammation has become easier with the availability of faecal calprotectin assay. Current anti-inflammatory therapy often leaves low-grade mucosal inflammation untreated, and therefore recurrent relapses occur. We need to investigate whether the therapeutic end-point of anti-inflammatory medications needs to be more rigorous and to aim at complete mucosal healing, confirmed by the normalization of mucosal inflammatory markers such as faecal calprotectin concentrations. Immunosuppressive therapy with azathioprine/ 6-mercaptopurine currently offers the best mucosal healing treatment with reduction of relapses, but newer biological agents might offer less toxic therapy. Clinical trials to test the feasibility and efficacy of such a paradigm shift in the medical management of Crohn's disease are now warranted.

Anti-Inflammatory Agents↗

PubMed2002

Use of the 'nutriceutical', bovine colostrum, for the treatment of distal colitis: results from an initial study.

BACKGROUND: Bovine colostrum is a rich source of nutrients, antibodies and growth factors. AIM: To examine the efficacy of colostrum enemas in the treatment of distal colitis using a randomized, double-blind, controlled protocol. METHODS: Fourteen patients (eight female), with a mean age of 45 years (range, 16-75 years) and mild to moderately severe distal colitis (Powell-Tuck scoring system), received colostrum enema (100 mL of 10% solution) or placebo (albumin solution) b.d. for 4 weeks. Both groups also received mesalazine (1.6 g/day) or, if already taking it, had a dose increment of 1.6 g/day. Disease activity was documented at 0, 2 and 4 weeks. RESULTS: After 4 weeks, the colostrum group showed a mean reduction in symptom score of - 2.9 (95% confidence interval (CI), - 5.4 to - 0.3), whereas the placebo group showed a mean response of + 0.5 (95% CI, - 2.4 to +3.4). The histological score improved in five of the eight patients in the colostrum group (mean response, - 0.9; 95% CI, - 1.69 to - 0.03), whereas the histological scores only improved in two of the six patients in the placebo group (mean response, 0.2; 95% CI, - 2.4 to +2.6). CONCLUSIONS: Bovine colostrum enema shows potential as a novel therapy for left-sided colitis with additional benefits over using mesalazine alone. Further studies appear to be warranted.

Adolescent↗

PubMed2002

Prevalence of methicillin-resistant Staphylococcus aureus colonization in surgical patients, on admission to a Welsh hospital.

Nosocomial infection with methicillin-resistant Staphylococcus aureus (MRSA) is on the increase and expensive to treat. Because surgical wound infection is one of the most frequent MRSA-induced infections with often disastrous consequences, it was decided to estimate the incidence and risk factors of MRSA colonization in surgical patients. All patients admitted to general surgical and orthopaedic wards were studied prospectively. At the time of admission, a detailed questionnaire was completed, nasal swabs and swabs of any pre-existing wound sites in each patient were sent for culture. Of 430 patients studied, 23 patients were positive for MRSA on admission. The prevalence of MRSA colonization in this study was 5.3% of whom 15 (65%) were nasal carriers and eight (35%) had MRSA colonization elsewhere. All nasal MRSA carriers had at least one documented hospital admission in the preceding year. Among the MRSA-positive patients, 10 (43%) either were admitted directly from, or had been previously admitted to, a nursing home. MRSA remains mainly a hospital-acquired infection although a significant proportion is acquired in the community. The risk factors identified were previous hospital admission, patients from nursing homes, male and aged over 70.

Adult↗

PubMed2002

Intestinal entry of prions.

Variant Creutzfeldt-Jakob disease is thought to be caused by infected prion protein via ingestion of contaminated beef. After ingestion of infected prion proteins, uptake by small intestine may be by either M-cell dependent or M-cell independent routes. A receptor for prion protein, laminin receptor precursor is expressed on the brush border of small intestinal epithelium in 40 % of subjects. The cellular prion protein expressed on the enteric nervous system might serve as the target for conversion to infectious prion protein and a route for spread to the central nervous system.

Creutzfeldt-Jakob Syndrome↗

PubMed2002

Testicular gametogenic and steroidogenic activities in cyclophosphamide treated rat: a correlative study with testicular oxidative stress.

The present work examined the changes in testicular activities in relation to testicular oxidative stress in cyclophosphamide as well as human chorionic gonadotrophin (hCG) co-treated cyclophosphamide treated Wistar strain rats. Testicular activities were evaluated by the quantification of spermatogenesis and by the measurement of steroidogenic key enzyme activities along with plasma levels of testosterone. Testicular oxidative stress in relation to cyclophosphamide treatment was monitored by the study of products of free radicals like conjugated dienes and malondialdehyde (MDA) as well as the activity of testicular antioxidant enzymes like peroxidase and catalase. Cyclophosphamide treatment at the dose of 5 mg/kg body weight/day for 28 days resulted a significant diminution in the activities of testicular delta 5, 3 beta-hydroxysteroid dehydrogenase (delta 5, 3 beta-HSD), 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) activities, plasma level of testosterone along with significant reduction in the number of germ cells at stage-VII of spermatogenesis. Levels of testicular MDA and conjugated dienes both were elevated whereas testicular peroxidase and catalase activities both were inhibited significantly in cyclophosphamide treated rats in comparison to control. After hCG co-administration at the dose of 5 I.U./kg body weight/day for 28 days in cyclophosphamide treated rats resulted a significant protection in the activities of testicular peroxidase and catalase along with significant decrease in the levels of MDA and conjugated dienes to the control level. Moreover, the testicular steroidogenic key enzyme activities and spermatogenesis along with plasma levels of testosterone were restored to the control level. Therefore, it may be concluded that there is a correlation between testicular steroidogenic activities as well as spermatogenesis and testicular oxidative stress in cyclophosphamide treated rats. Moreover, as restoration of plasma testosterone to the control level is noted in hCG co-treated cyclophosphamide treated rat, therefore, the results suggest that testosterone may be the key regulator for this correlation.

Animals↗

PubMed2002

Oncogenic human papillomavirus (HPV) infection and uterine cervical cancer: a screening strategy in the perspective of rural India.

The predominance of cervical cancer in India can mostly be attributed to the lack of early screening. The objective of the present study has been, therefore, to determine a cost-effective oncogenic human papillomavirus (HPV)-based cervical cancer screening plan for rural Indian women. The results showed that in normal women, highest prevalence of HPV 16/18 infection was in the age group < or =23 years and lowest in > or =44 years with an insignificant change in between. HPV 16/18 infection was significantly associated with cervical erosion at age < or =23 years, but not with cytology or visual inspection with acetic acid testing at any age. The low-grade cytological lesions, however, increased only with increase in age. Fourteen per cent of the cervical malignancy was also found to be present in the age group 24-33 years with an 87% HPV infection. Here we proposed a cost-effective screening scheme in which HPV testing must be performed in women (a) < or =23 years with cervical erosion and (b) 24-43 years, as an adjunct to Pap smears (both HPV and cytology were prevalent in this group). For women > or =44 years, HPV testing might not be useful, since abnormal cytology was more prominent over the viral infection. We infer that by not performing HPV test in the group < or =23 years, approximately 76% of the high-risk HPV-infected individuals potentially "at risk" for developing cervical cancer might be missed.

Acetic Acid↗