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Biomedical subjects

S Bhattacharya

Publications and source records attributed to S Bhattacharya.

At least 73 records · Page 4Linked to original sources
PubMed2003

Anti-steroidogenic activity of methanolic extract of Cuscuta reflexa roxb. stem and Corchorus olitorius Linn. seed in mouse ovary.

Methanolic extract (ME) of both C. reflexa stem and C. olitorius seed arrested the normal oestrus cycle of adult female mouse and significantly decreased the weight of ovaries and uterus. The cholesterol and ascorbic acid contents in ovaries were significantly increased in the treated mice. Two key enzymes, delta5-3beta-hydroxysteroid dehydrogenase and glucose-6-phosphate dehydrogenase, were decreased significantly in ME of both C. reflexa stem and C. olitorius seed after 17 days of treatment. High level of substrates and low level of enzymes indicate the inhibition of steroidogenesis in treated mice and may be due to the presence of flavonoids.

Animals↗
PubMed2002

Signaling through the JAK/STAT pathway, recent advances and future challenges.

Investigation into the mechanism of cytokine signaling led to the discovery of the JAK/STAT pathway. Following the binding of cytokines to their cognate receptor, signal transducers and activators of transcription (STATs) are activated by members of the janus activated kinase (JAK) family of tyrosine kinases. Once activated, they dimerize and translocate to the nucleus and modulate the expression of target genes. During the past several years significant progress has been made in the characterization of the JAK/STAT signaling cascade, including the identification of multiple STATs and regulatory proteins. Seven STATs have been identified in mammals. The vital role these STATs play in the biological response to cytokines has been demonstrated through the generation of murine 'knockout' models. These mice will be invaluable in carefully elucidating the role STATs play in regulating the host response to various stresses. Similarly, the solution of the crystal structure of two STATs has and will continue to facilitate our understanding of how STATs function. This review will highlight these exciting developments in JAK/STAT signaling.

Animals↗
PubMed2002

Driven dynamics of the vortex-phase mixture near the peak effect: the "vortex capacitor".

A phenomenological model of vortex dynamics in the vicinity of the peak effect, which considers a coexistence of two vortex phases with different critical current densities, is proposed. It provides a quantitative description of the widely reported anomalous dynamic effects in terms of "contamination" and "annealing" of the vortex matter. Scanning ac Hall microscopy in the superconductor NbSe(2) is used to obtain the first real-space visualization of pinning in the driven vortex lattice. The results are consistent with the proposed scenario.

Journal Article↗
PubMed2002

Intramural pseudodiverticulosis of the esophagus.

Esophageal intramural pseudodiverticulosis (EIPD) is a rare condition seen in the elderly, with a male-to-female ratio of 3:2. Multiple small outpouchings occur in the submucosa of the esophageal wall, caused by dilation of the excretory ducts of the mucus glands. This disorder may be associated with gastroesophageal reflux, motility disorders, candidiasis, or other conditions. Inflammation, resulting in periductal fibrosis and compression of the duct orifices, may be a causative factor. Usually, EPID presents with progressive dysphagia related to esophageal stenosis or strictures in the great majority of patients. Radiologic examination is more sensitive than endoscopy in detecting these tiny saccular diverticula in the esophageal wall. They often are noted to disappear after esophageal dilation, but may persist asymptomatically in some patients. We report two cases of dysphagia associated with reflux and Candida infection in elderly patients. The diagnosis of EIPD was made, and both patients were treated successfully. A review of the available literature suggests that EIPD may be missed easily because of subtle endoscopic and radiologic changes, but that once diagnosed, conservative management leads to satisfactory control of the symptoms.

Aged↗
PubMed2002

In vitro fertilisation for unexplained subfertility.

BACKGROUND: In vitro fertilisation (IVF) is now a widely accepted treatment for unexplained infertility (RCOG 1998). However, with estimated livebirth rates per cycle varying between 13% and 28%, it's effectiveness has not been rigorously evaluated in comparison with other treatments. With increasing awareness of the role of expectant management and less invasive procedures such as intrauterine insemination, concerns about multiple complications and costs associated with IVF, it is extremely important to evaluate the effectiveness of IVF against other treatment options in couples with unexplained infertility. OBJECTIVES: The aim of this review is to determine, in the context of unexplained infertility, whether IVF improves the probability of livebirth compared with 1. expectant management 2. clomiphene citrate (CC) 3. intra uterine insemination (IUI) alone 4. IUI with controlled ovarian stimulation and 5. Gamete IntraFallopian Transfer (GIFT). SEARCH STRATEGY: RCTs were identified using the search strategies developed for the Menstrual Disorders and Subfertility Group. See Review group for more information. SELECTION CRITERIA: Only randomised controlled trials were included. Livebirth rate per woman was the primary outcome of interest. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed eligibility and quality of trials. MAIN RESULTS: Nine randomised controlled trials were identified. In two we could not extract data separately for unexplained infertility cases, two were non-randomised, one reported no valid rates (included in the review and not in the meta-analysis), leaving four trials for analysis. One trial compared two different interventions (IVF versus IUI with or without ovarian stimulation) and one study compared three interventions (IVF versus IUI with ovarian stimulation and GIFT). The number of trials assessing the effectiveness of IVF with the other treatments were as follows: IVF versus expectant management (one), IVF versus IUI (one), IVF versus IUI with ovarian stimulation (two) and IVF versus GIFT (three). Livebirth rate per woman was reported in two studies and three studies determined clinical pregnancy rate per woman. Multiple pregnancy rate was reported in three trials. Two studies reported ovarian hyperstimulation syndrome (OHSS) as an outcome measure. There were no comparative data for clomiphene citrate, and no comparative data on livebirth rates for expectant management or GIFT. There was no evidence of a difference in livebirth rates between IVF and IUI either without (OR 0.51, 95% CI 0.23 to 1.1) or with (OR 0.87, 95% CI 0.42 to 1.8) ovarian stimulation. There was no evidence of a difference in clinical pregnancy rates between IVF and expectant management. There was no significant difference in the clinical pregnancy rates between IVF and GIFT (OR 0.47, 95% CI 0.24 to 0.92). There was no evidence of a difference in the multiple pregnancy rates between IVF and either IUI with ovarian stimulation (OR 1.59, 95% CI 0.68 to 3.70) or GIFT (OR 0.47, 95% CI 0.08 to 0.58). Clinical heterogeneity was present among the studies included. However, there was no evidence of statistical heterogeneity, which allowed the studies to be combined for statistical analysis. REVIEWER'S CONCLUSIONS: Any effect of IVF relative to expectant management, clomiphene citrate, IUI with or without ovarian stimulation and GIFT in terms of livebirth rates for couples with unexplained subfertility remains unknown. The studies included are limited by their small sample size, so that even large differences might be hidden. Livebirth rates are seldom reported. Adverse effects such as multiple pregnancies and ovarian hyperstimulation syndrome have also not been reported in most studies. Larger trials with adequate power are warranted to establish the effectiveness of IVF in these women. Future trials should not only report rates per woman /couple but also include adverse effects and costs of the treatments compared as outcomes. Factors that have a major effect on these outcomes such as fertility treatment, female partner's age, duration of infertility and previous pregnancy history should also be considered.

Female↗
PubMed2002

An analysis of 11,196 burn admissions and evaluation of conservative management techniques.

We present an 8-year analysis (1993-2000) of 11,196 burn admissions with an average of 116.6 patients per month. Patients were largely treated by conservative techniques. The mean burn percentage was 50.35. Almost 80% of admissions were in the 16-55 years age group. Paediatric and geriatric burns were 17.1 and 3.1%, respectively. Flame burns accounted for 82.15% of admissions and of these 77.5% were sustained in the kitchen. A total of 35.32% of flame accidents were due to malfunctioning kerosene pressure stove. The overall mortality was 51.80%. These figures need further qualification because 46.8% of patients had more than 50% BSA burns and 50.72% patients reported to the hospital more than 6h after sustaining burns. Patients with <60% BSA burns, and who were received within 6h of injury had a mortality of 23% only. Significantly, 1078/1952 deaths (55.23%) of patients <60% BSA burns took place in first 6 days of admission when 3639 patients with <60% BSA injury were received more than 6h after burn injury. This reflects that even if economic constraints preclude one from having the best infrastructure reasonable mortality rates are still achievable with conservative line of management, even in face of a heavy work load. This also makes one question the cost effectiveness of high cost technology in burn management.

Accidents↗
PubMed2002

Antibacterial activity of Terminalia pallida.

The methanol extract of the dried fruit powder of Terminalia pallida was evaluated for antimicrobial activity. The methanol extract showed a broad spectrum of antibacterial activity.

Anti-Bacterial Agents↗
PubMed2002

Antimicrobial activity of Eupatorium ayapana.

Petroleum ether and methanolic extracts of leaves of Eupatorium ayapana were tested for their antimicrobial activity. The petroleum ether extract showed higher antibacterial and antifungal activity than the methanolic extract.

Anti-Bacterial Agents↗
PubMed2002

A case study of familial anti-phospholipid syndrome.

Anti-phospholipid syndrome (APS) may have a familial association. In particular, association has been demonstrated between APS and HLA-DR 4, HLA-DR 7 and HLA-DRB1 14 alleles. Here we have described a family sharing the common haplotype of HLA-DR 7 where definite or probable anti-phospholipid syndrome has been identified in six of the seven family members. Apart from the index case, the other family members have demonstrated partial association in spite of sharing the incriminated haplotype. This could be ascribed either to variable penetrance of the involved genes or to the role of an unaccounted for environmental factor. Alternatively, it is possible that the coexistence of the HLA haplotype and the anti-phospholipid antibodies is coincidental.

Adult↗
PubMed2002

Outcome of consecutive pregnancies in a patient with Bombay (Oh) blood group.

A young lady with a rare Bombay (Oh) blood group had two successive uneventful pregnancies. Her serum contained a potent high-titre anti-H and serological as well as chemiluminescence tests, suggesting that the antibody was haemolytic. Her husband was of the normal H status. Theoretically, both babies should have been positive for the H antigen and should have suffered from haemolytic disease of the newborn. This apparent conundrum could be owing to the weak expression of the H antigens on the infant red cells.

ABO Blood-Group System↗
PubMed2002

Problem of timely diagnosis in anthrax meningitis.

Anthrax continues to remain a problem in parts of India. Meningitis is often a complication encountered among cases with cutaneous anthrax. We have encountered a dozen cases of anthrax meningitis in our hosptal in the past decade. A sudden unexplained rise in cases in the past two years with hundred percent mortality stresses the need for rapid confirmatory diagnosis. Most of the cases admitted with central nervous system involvement had a provisional diagnosis of conditions other than anthrax meningitis. A strong clinical suspicion with a simple Gram stain smear of the CSF will help confirm anthrax meningitis in endemic areas.

Adult↗
PubMed2002

Antineoplastic effect of new boron compounds against leukemic cell lines and cells from leukemic patients.

Three new boron compounds, dihydroxy (oxybiguanido) boron (iii) hydrochloride monohydrate (HB), guanidine biboric acid adduct (GB) and hydroxosalicyl hydroxomato boron (iii) (SHB) were studied to observe their antineoplastic effect, if any. Leukemic cells isolated from acute lymphatic leukaemia (ALL) patients and chronic myeloid leukaemia patients (CML) and myeloid leukemia cell lines (HL 60 and U-937) showed cell growth inhibition after treatment with the boron compounds. MTT assay showed that the growth of metabolically active cells was inhibited by treatment with these drugs. The molecular mechanism by which SHB induced apoptosis in immature blast cells was also investigated by ladder formation in gel electrophoresis.

Acute Disease↗
PubMed2002

Human fetal adrenal transplant: a possible role in relieving intractable pain in advanced rheumatoid arthritis.

BACKGROUND: The art of transplant surgery has gone a long way in establishing itself as an important discipline in medicine with the support of molecular biology, immunology, biochemistry, etc., as the ultimate treatment for the restoration of function of a failing organ. With the progressive increase in the life expectancy of human beings, there is an increasing discrepancy in the demand and supply of organ grafts. A less efficient alternative could be synthetic or mechanical grafts. Nucleated cell therapy, that is, cellular transplant, is a promising new area of study with its proven efficacy in neuro-degenerative disorders, hematopoietic disorders, diabetes and trauma-induced tissue loss, to name a few. Human fetal cell/tissue with its intrinsic hypo-antigenic advantage (up to 20 weeks of study), could be an interesting area of cellular/tissue transplant. Our research group has earlier reported on the safe use of umbilical cord whole blood and the successful transplant of a human fetal lung, heart, pancreas, liver, thymus, in an artificially prepared vascular subcutaneous axillary fold in which there was no feature of hyper-acute, acute or chronic rejection of the graft in HLA- and sex-randomized adult recipients, without concomitant immunosuppressives or radiation of the host to potentiate the survival of the fetal graft (within 20 weeks of gestation) within the lowest observation period of one month. The present study was aimed at examining the role of developing fetal adrenal transplants for patients with rheumatoid arthritis and severe pain due to involvement of inflammatory and neuropathic components. MATERIALS AND METHOD: Ten cases were enrolled in the present study after thorough informed consent and approval by the ethical committee of the institute. The age of the patients varied from 50 to 76 years and the group was comprised of three males and seven females. The age of the adrenal grafts varied from 16 to 20 weeks and these were collected from mothers admitted for hysterotomy and ligation. These long-standing rheumatoid patients (suffering for five to 15 years), presented with at least four of the seven 1987 revised criteria of the American College of Rheumatology for diagnosis of rheumatoid arthritis. A 2.5 cm long and 2 cm deep tissue space was dissected and prepared in each transplant recipient at the axilla using diathermy and knife after infiltrating the site with one percent lignocaine solution. The tissue collected from the consenting mother undergoing hysterotomy and ligation was inserted into this site, and the site was closed with 00 atraumatic vicryl. All necessary pre- and postoperative surgical precautions were taken to prevent infections. Sequential total count and differential count of leucocytes were undertaken to analyze the impact of the transplant on the host. After one month, a part of the transplanted fetal tissue was recovered for histological staining to examine whether there was any graft versus host reaction. RESULTS AND ANALYSIS: All ten patients tolerated the transplant procedure well. There was no fever, intractable pain or any other specific serious side-effect which could justify the removal of the transplant before one month. There was no discharge from the incision site and the healing of the scar was by and large normal. There was no unusual leucocytosis, lymphocytosis and the retrieved graft tissue did not suggest transplant rejection. However, there was definite pain relief, reduction in swelling and improvement of mobility of varying degree in a majority of the patients which was perceivable from the 15th day onwards. There was also a sense of well being (in 80%) and a gain in weight of three pounds or more (in 70%) among the fetal transplant recipients. DISCUSSION AND CONCLUSION: To understand the underlying mechanism, in case of pregnancy immunotolerance, we are of the opinion that emphasis should be placed on the role of non-specific and non-cytopathic blocking antibodies produced during pregnancy. The hypo-antigenicity of the developing human fetal system may possibly contribute to the production of this blocking antibody during pregnancy, and thus may play a role in the lack of recognition by the host's HLA system. This behaviour of the developing human fetal tissue provides some advantages over adult tissue for fetal cell/tissue transplantation purposes. The relief of pain, inflammation and restoration of mobility may be due to the effect of the transplanted adrenal graft, with the medullary component contributing to endorphin-like substance liberation and the cortical component contributing to glucocorticoid synthesis.

Adrenal Glands↗
PubMed2002

Melioidosis--a report from Pondicherry, South India.

Melioidosis is an acute infectious disease caused by a safety-pin-shaped gram-negative bacteria called Burkholderia pseudomallei. Here, we report the first case of melioidosis in a middle aged male agricultural worker, from Pondicherry. The isolation of this organism from subcutaneous nodules on the extensor aspect of his limbs underlines the diversity of its clinical presentation. Difficulty in identifying the organism which mimics any other non-fementing gram-negative bacilli (NFGNB) on cursory examination, highlights the importance of identification of NFGNB in endemic areas for specific treatment and prevention.

Anti-Bacterial Agents↗
PubMed2002

Can human fetal cortical brain tissue transplant (up to 20 weeks) sustain its metabolic and oxygen requirements in a heterotopic site outside the brain? A study of 12 volunteers with Parkinson's disease.

BACKGROUND: Neural and stem cell transplantation is emerging as a potential treatment for neurodegenerative diseases from Parkinson's to Huntington's disease. Stereotactic placement of dopaminergic neurons in the caudate-putamen (striatum), is being attempted in centers of excellence and has proved to be beneficial. Basic research using cell transplantation indicates that structural development mechanisms seen in immature brains, i.e., fetal brains, can also function in the adult brain. The adult brain consumes 15% of the resting cardiac output for its metabolic needs. While most human tissues can sustain an anaerobic assault for a few minutes up to 30 minutes, a sudden total lack of oxygen supply to the brain cells in an adult will render the person unconscious within five to ten seconds. Our team has been working on the problem of human fetal tissue response to antigenic assault for the last two decades. In the present series, 12 patients with prolonged histories of Parkinsonism, who were not responding to anti-Parkinsonian drugs, and could not afford costly stereotactic surgery or deep brain stimulation and other modalities of recent Parkinson's disease treatment, were enrolled in the study. MATERIALS AND METHOD: After obtaining proper informed consents from the patients or their guardians and from the multidisciplinary ethical committee, the patients, varying in age from 45 to 75 years and suffering for many years with Parkinsonism, were enrolled in the heterotopic brain tissue transplant programme. We followed standard antiseptic, aseptic and premedication protocols, after selecting a proposed site of transplantation of the brain in the axillary fold of the skin, under local infiltration anaesthesia. In an adjacent OR, a fetus was collected from a consenting patient undergoing hysterotomy and ligation (before 20 weeks), under general anaesthesia. Within a minute of hysterotomy, the fetal brain tissue was dissected, and under the guidance of the operative microscope, 1 g of fetal cortical brain tissue was dissected and weighed in an electronic machine. The tissue was collected from around 1 cm of the frontal opercula of the developing human fetal brain and grafted in the already dissected and prepared subcutaneous site in the axilla and the skin was closed. Hematological parameters (Hgb; total count, Tc; differential count, Dc; erythocyte sedimentation rate, ESR) were estimated sequentially up to one month. A small portion of the transplanted tissue was retrieved after one to two months, and a serial histological study was done along with a clinical assessment of the disease condition as per the specifications of the Unified Parkinson's Disease Rating Scale. The results were matched with the pre-transplant ratings of the individual cases. Presenting dyskinesia was also rated (0-4), on the basis of objective criteria assessment like walking, putting on a coat, lifting a cup to drink, etc. RESULTS AND ANALYSIS: Initially 30 patients suffering from advanced Parkinson's disease (PD) were approached after getting the necessary clearance from the institutional multidisciplinary ethical committee; however, we have been able to arrange transplantation in only 12 cases so far. These patients were evaluated at the pre- and one month post-transplant period by the Unified Parkinson's Disease Rating Scale (0-108) and the minimum score was 40 in the motor portion of the unified scale at the pre-transplant state. Evaluation of the patients after one month revealed mild improvement of the pre-transplant scoring (up to 33.3%) in 41.6% of the cases, and moderate improvement (up to 66.6%) in another 41.6% of the cases. While 16.8% of the cases did not show any improvement from the basal score, i.e., the pre-transplant score, there was a definite sense of well being and rise in weight (2-4 pounds) noted in each case and there was also a reduction of the L-Dopa dosage in 75% of the cases. There was also a 58.3% improvement in the bradykinesia scoring from the pre-transplant level. What is intriguing is the survival, growth and proliferation of the grafted fetal brain tissue in the HLA- and sex-randomized adult axilla without any immunosuppressive support. Not a single histological study of the fetal brain tissues after removal from the axilla showed any signs of graft vs. host or inflammatory reaction (Figures 1-9) but there were features of growth of the transplanted cortical brain tissue along with its different components like neurogenesis, gliogenesis, early neovascularisation and angiogenesis, etc. There was also no systemic leucocytosis or lymphocytosis. DISCUSSION AND CONCLUSION: Histological evidence at the transplanted tissue site suggests that fetal cortical brain tissue can sustain life in sex-randomized, HLA-randomized adult hosts, without the support of immuno-suppressive drugs and the tacit support of the blood-CSF and blood-brain barrier and other specific requirements of adult brain cells in the skull. Whether the clinical improvement in PD is transient or long lasting is presently under investigation along with basic questions like, is it due to transplanted fetal dopaminergic or non-dopaminergic neurons or is it the growth factors and the cytokine mediated hitherto unknown reactions causing the clinical improvement.

Aged↗
PubMed2001

Incorporation of oxyethylene units between hydrocarbon chain and pseudoglyceryl backbone in cationic lipid potentiates gene transfection efficiency in the presence of serum.

Four novel cationic lipids with different numbers of oxyethylene units at the linkage region between the pseudoglyceryl backbone and the hydrocarbon chains have been synthesized and used as mixtures with 1,2-dioleoyl-L-alpha-glycero-3-phosphatidyl ethanolamine (DOPE) for liposome-mediated gene transfection. Incorporation of different numbers of oxyethylene (-CH(2)CH(2)O-) units between long hydrocarbon chain at the C-1 and C-2 positions of the pseudoglyceryl skeleton improved the transfection efficiency considerably compared to the one in which the chains were connected via simple ether links. A pronounced improvement in the gene transfer efficiency was observed with the unsymmetrical cationic lipid 3 in which the long hydrocarbon at the C-1 position of the pseudoglyceryl segment is connected via two (-CH(2)CH(2)O-) units. Notably, the transfection ability of lipid 3 with DOPE in the presence of serum was significantly greater than LIPOFECTAMINE. This suggests that introduction of oxyethylene units between long hydrocarbon chains at the C-1 and C-2 positions of the pseudoglyceryl skeleton provides a novel strategy to achieve efficient gene transfer, especially in conditions where the presence of serum is critical.

Blood↗