Biomedical subjects
Publications and source records attributed to R Singh.
We report a case of ulcerative colitis where chest radiograph and high-resolution computed tomography (HRCT) of the lungs revealed bilateral upper lobe fibrosis, which was misdiagnosed and treated as pulmonary tuberculosis. The diagnosis of ulcerative colitis was confirmed by sigmoidoscopy and rectal biopsy.
Out of 11234 patients reporting to our outdoor during June 2001 to June 2002, 2594 patients (23.09%) had low back pain. 4358 roentgenograms were done in these patients, a mean of 1.68 per patient. These patients were interviewed and their psychosocial and demographic details were compared with 1000 controls who did not have back pain but attended outdoor for other reasons. In the low back pain group, 67% had psychosocial issues, 57% were in blue-collar jobs, 26% had to change/leave their profession, and 38% did not enjoy their present job. All patients had used NSAIDS at some stage of illness and 64% were advised exercises for the back. The comparative figures in control group were 19% with psychosocial issues, 34% in blue-collar jobs (heavy manual workers), 7% had to switch over to new job, 6% did not relish their present job. Hence, it is concluded that along with exercises and NSAIDS, sufficient consideration should be given to short centre-based intensive rehabilitation program followed by a home-based program for chronic low back pain patients.
A 28-years-old female presented with severe autoimmune hemolytic anemia (AIHA), warm antibody mediated, and right side tubo-ovarian (TO) mass. There was sub-optimal response to immunosuppressive therapy (IST). Eight months later she underwent ovarian cystectomy which resulted in complete remission of AIHA without the need for IST. Pathological examination of the TO mass revealed benign ovarian cyst. Our case highlights the need to search for ovarian cyst/mass in females presenting with AIHA. Since immunosuppressive therapy is usually ineffectual in AIHA associated with ovarian cyst, it may be appropriate to contemplate surgery before embarking on IST in such cases.
Cutaneous polyarteritis-nodosa-like lesions are rarely described in Behcet's disease. We report a case of recurrent cutaneous polyarteritis-nodosa-like (C-PAN-like) lesions in Behcet's disease with multiple deep vein thromboses as part of systemic vasculitis. The mucocutaneous manifestations responded to prednisolone; however, C-PAN-like lesions were refractory and responded to oral cyclosporine. We conclude that C-PAN-like lesions may be marker of severe disease and require intense immunosuppressive therapy.
Chronic thromboembolic pulmonary hypertension (CTEPH) is a part of the spectrum of venous thromboembolism in which pulmonary thrombus fails to resolve, resulting in occlusion of the major pulmonary artery. Diagnosis of this disease is important as it is potentially curable by pulmonary thromboendarterectomy. A case of CTEPH diagnosed non-invasively on spiral computerized (CT) pulmonary angiography is reported.
Membrane microdomains known as lipid rafts have been shown recently to be involved in Fas signalling and apoptosis in T and B cell lines. Here, we have investigated further the role of lipid rafts in Fas-induced apoptosis in non-transformed human CD4 T cells. We show that Fas-induced apoptosis in CD4 T cells was inhibited by the lipid raft disrupter methyl-beta-cyclodextrin. When lipid rafts were isolated from control and Fas ligand treated cells, we found that a small proportion of Fas was present in the raft fraction in untreated cells and that this was greatly increased upon Fas ligation. The other components of the Death Inducing Signalling Complex (DISC), FADD, and procaspase 8, were also present at higher levels in the raft fraction isolated from Fas ligand treated cells. We conclude that formation of the DISC occurs in lipid rafts and that these membrane microdomains are required for efficient Fas signalling and apoptosis.
Nutrition and immunology are interrelated. Several nutrients like arginine, glutamine, omega-3-fatty acids and nucleotides enhance cellular immunity, modulate tumor cell metabolism and improve clinical outcome in stress situations. Glutamine supplementation has been shown to decrease incidence of sepsis and to reduce length of hospital stay in bone marrow transplant patients, low birth weight infants, surgical and multiple trauma patients. Studies with arginine have shown a reduction in infectious complications and lower mortality, however a better understanding of the biology of arginine is needed. Omega-3-fatty acid supplimentation as in fish oil stimulates the immune system. The beneficial effects of immunonutrition in surgical patients has been demonstrated in several studies. It significantly reduces infectious complications and length of hospital stay. In critically ill patients immunonutrition may decrease infectious complications but it is not associated with a mortality advantage. Pediatric experience is limited, but the future is promising.
Explore the source record for details and available documents.
The cannabinoid CB1 receptor, a member of the Rhodopsin (Rho) family of G protein coupled receptors (GPCRs), exhibits high levels of constitutive activity. In contrast, Rho exhibits an exquisite lack of constitutive activity. In Rho, W6.48(265) on transmembrane helix 6 (TMH6) is flanked by aromatic residues at positions i-4 (F6.44) and i + 3 (Y6.51), while in CB1 the residues i-4 and i + 3 to W6.48 are leucines (L6.44 and L6.51). Based upon spectroscopic evidence, W6.48 has been proposed to undergo a rotamer switch (chi1 g+ -->trans) upon activation of Rho. In the work reported here, the biased Monte Carlo method, Conformational Memories (CM) was used to test the hypothesis that the high constitutive activity exhibited by CB1 may be due, in part, to the lack of aromatic residues i-4 and i + 3 from W6.48. In this work, the W6.48 rotamer shift (chi1 g+ -->trans) was used as the criterion for activation. Conformational Memories (CM) calculations on WT CB1 TMH6 and L6.44F and L6.51Y mutant TMH6s revealed that an aromatic residue at 6.44 tends to disfavor the W6.48 chi1 g+ -->trans transition and an aromatic residue at 6.51 would require a concomitant movement of the Y6.51 chi1 from trans-->g+ when the W6.48 chi1 undergoes a g+ -->trans shift. In contrast, CM calculations on WT CB1 TMH6 revealed that the presence of leucines at 6.44 and 6.51 provide W6.48 with greater conformational mobility, with a W6.48 transchi1 preferred. Conformational Memories calculations also revealed that the W6.48 chi1 g+ -->trans transition in WT CB1 TMH6 is correlated with the degree of kinking in TMH6. The average proline kink angles for TMH6 were higher for helices with a W6.48 g+ chi1 than for those with a W6.48 transchi1. These results are consistent with experimental evidence that TMH6 straightens during activation. Transmembrane helix (TMH) bundle models of the inactive (R) and active (R*) states of CB1 were then probed for interactions that may constrain W6.48 in the inactive state of CB1. These studies revealed that F3.36 (transchi1) helps to constrain W6.48 in a g+ chi1 in the inactive (R) state of CB1. In the R* state, these studies suggest that F3.36 must assume a g+ chi1 in order to allow W6.48 to shift to a transchi1. These results suggest that the W6.48/F3.36 interaction may act as the 'toggle switch' for CB1 activation, with W6.48 chi1 g+/F3.36 chi1 trans representing the inactive (R) and W6.48 chi1 trans/F3.36 chi1 g+ representing the active (R*) state of CB1.
Lectins are proteins or glycoproteins of nonimmune origin, which bind specifically to carbohydrate structures. They are widespread in the human diet, and many are resistant to digestion. High doses of lectins have been shown to stimulate intestinal and pancreatic growth. The aim of the present study was to investigate the long-term actions of low doses of lectins on the rat intestine and pancreas. A long-term carcinogenesis study was performed using low levels (40 micro g/rat/day) of peanut (PNA) or mushroom lectin (ABA) which bind to O-linked (mucin-type) oligosaccharides in the gut. While this was primarily designed as a colon carcinogenesis study, the pancreas was also investigated. No significant changes in colon carcinogenesis were seen, however, the colons were slightly heavier in the lectin treated groups. The weight of the pancreas was significantly greater (by 18 and 23%) in both lectin treated groups (P < 0.03/0.001). The weights of the acini and septal tissue were also increased by 39-46% in PNA and ABA fed animals, respectively (P < 0.002); there was no significant change in the endocrine pancreas. In conclusion, long-term feeding of low doses of lectin can influence pancreatic growth, and this trophic action may have potential adverse implications for the development of pancreatic cancer in humans.
OBJECTIVE: As crystals may contribute to inflammation in osteoarthritis (OA), it is hypothesized that colchicine may have symptom/disease modifying effects in OA. The objective of this study was to evaluate the symptomatic benefit of addition of colchicine to a regimen of intraarticular steroids and piroxicam in patients with knee OA with inflammation. DESIGN: 39 patients with OA of the knee with persisting inflammation, despite at least 2 weeks of piroxicam, were subjected to intraarticular steroid injection and randomly assigned to receive colchicine 0.5 mg twice daily or placebo in a randomized, double blind, placebo-controlled trial over 5 months. RESULTS: VAS for index knee pain (VAS-pain) and total KGMC score (a modified WOMAC index) at 16 and 20 weeks were significantly better in the colchicine group than the corresponding scores in controls. The benefit persisted on multivariate analysis at 16 weeks (Hotellings T(2)=18.6, F(5,33)=3.3154, P=0.015). The proportion of patients who had 30% or greater response at 16 weeks was significantly higher in the colchicine group in VAS-pain (69% vs 15%) and total KGMC scores (74% vs 45%) and the significance persisted on combined analysis using Mantel-Haenszel test (M-H Risk=5.9, 95% C.I.: 2.08 to 16.73). At 20 weeks, benefit of colchicine therapy was seen on pooled analysis only (M-H risk=3.71, 95% C.I.: 1.07=8.02). CONCLUSION: The addition of colchicine produced significantly greater symptomatic benefit at 16 and 20 weeks than intraarticular steroid and piroxicam alone in patients with knee OA with inflammation.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
PURPOSE: To examine South Asian immigrant women's health promotion issues and to facilitate the creation of emancipatory knowledge and self-understanding regarding health-promoting practices; to promote health education and mobilization for culturally relevant action. METHOD: The study was based on critical social theory; the research model was participatory action research (PAR). Two groups of South Asian women (women from India and of Indian origin) who had immigrated to Canada participated in the project. The qualitative data were generated through focus groups. Reflexive and dialectical critique were used as methods of analyzing qualitative data. The data were interpreted through reiterative process, and dominant themes were identified. FINDINGS: Three themes that were extracted from the data were: (a) the importance of maintaining culture and tradition, (b) placing family needs before self, and (c) surviving by being strong. An issue for action was the risk of intergenerational conflicts leading to alienation of family members. Over a period of 3 years, the following action plans were carried out: (a) workshops for parents and children, (b) sharing of project findings with the community, and (c) a presentation at an annual public health conference. CONCLUSIONS AND IMPLICATIONS: The project activities empowered participants to create and share knowledge, which was then applied toward action for change. Health and health promotion were viewed as functions of the women's relationships to the world around them.
Explore the source record for details and available documents.
We report the case of a 72-year-old female with sarcoidosis who developed a central retinal artery occlusion in her left eye in association with persistently high titers of IgG anti-cardiolipin antibodies. Only two previous cases of antiphospholipid antibody syndrome in association with sarcoidosis have been reported. Our patient's vision stabilized on anti-coagulant therapy along with concomitant treatment of sarcoidosis-related uveitis with methotrexate.
Explore the source record for details and available documents.
Retrospective analysis of 27 patients of thalamic glioma including adults and children treated over a period of 7 years from 1991-1997 was done. The study group included 19 males and 8 females; 9 patients were less than 15 years and 18 patients more than 15 years of age at the time of diagnosis. The commonest symptoms were headache and vomiting. 12 patients underwent VP shunt as an initial procedure and 7 underwent total or partial surgical resection. Confirmed histopathological examination was possible in 16 patients; while 12 had low grade astrocytoma, 4 cases had high grade histology. All patients were treated with radiotherapy to a total dose of 50-60 Gy in 25-30 fractions. Median follow up was 9.63 months. The disease free survival in these patients was 28% at 2 years. Prognostic factors which included age, sex, duration of symptoms, surgical procedures, histology and radiotherapy dose were evaluated for significance. A subtotal resection conferred a better prognosis.