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S K Das

Publications and source records attributed to S K Das.

At least 145 records · Page 8Linked to original sources
PubMed1999

The significance of creatine kinase in cardiac patients with acute limb ischaemia.

OBJECTIVE: The value of creatine kinase (CK) and aspartate transaminase (AST) has not been previously evaluated following cardiac surgery in the diagnosis of acute limb ischaemia. Our objective was to assess the value of CK and AST with reference to the diagnosis of limb ischaemia, effect on renal function and prognosis following cardiac surgery. DESIGN: all patients entering ICU had daily CK and AST measurements over a two -year period. A retrospective study of patients with CK values >5,000 U/L was performed. SETTING: adult intensive care unit of a secondary and tertiary referral centre for cardiothoracic surgery with on site facilities for vascular surgery. PATIENT: twenty-seven patients had CK values greater than 5,000 U/L. A further random sample of 35 patients, with no limb ischaemia were used to give medians for CK and AST following cardiac surgery. INTERVENTIONS: twelve of twenty-seven (44%) patients were noted to have acutely ischaemic limbs; 6 of these (CK>16,000 U/L) underwent surgical intervention. MEASURES: serum levels of CK, Peak CK, AST, Peak AST and CK/AST ratios. Related to procedure and outcome in terms of mortality and morbidity including, acute limb ischaemia defined on clinical grounds and renal failure defined as creatinine >200 pmoles/L. RESULTS: The median values for CK and AST immediately following uncomplicated cardiac surgery were 135 (IQR 36-383) and 43 (IQR 26-58) respectively. Median CK for the patients (CK>5,000) without clinical ischaemia was 7,440 U/L compared to the group with ischaemia 17,472 U/L (p<0.05). Renal failure developed in 48% of all patients. Eight of the 9 patients with CK>15,000 developed renal failure compared to 5 of the 13 with CK 5,000-15,000 U/L (p<0.01). 30% of patients underwent haemofiltration; of these, 87% died. For patients with ischaemia peak CK and creatinine correlated. (r = 0.83, p<0.05) Day of peak CK and peak AST correlated (r = 0.92, p<0.01). Logged values of CK with log values of AST showed a highly significant relationship (beta = 1.16, p<0.001). The overall mortality was 33%. CONCLUSIONS: PATIENTs who develop limb ischaemia following cardiac surgery have a high morbidity and mortality. A CK of 17,000 U/L (5667-46539) is indicative of serious limb ischaemia. Renal failure is likely to develop in patients with CK>15,000 U/L. AST may become a useful additional marker of limb ischaemia.

Acute Disease↗
PubMed1999

Toward a rational management of concomitant carotid and coronary artery disease.

BACKGROUND: Patients with angina undergoing carotid endarterectomy have a high perioperative mortality. Our aim was to assess the outcome of carotid endarterectomy in patients with concomitant coronary artery disease, in particular, to examine the timing of carotid endarterectomy and CABG. METHODS: A retrospective study was performed at a tertiary and secondary referral centre for cardiovascular disease. Over a five-year period 71 carotid endarterectomies and 6,590 coronary artery bypasses were performed. Significant (>70%) internal carotid stenoses were found in 35 (0.5%) patients due for CABG. Of these, 23 patients underwent Combined procedures (Carotid and CABG), 9 Reverse staged (CABG then Carotid), and 3 Prior staged carotid endarterectomies (Carotid then CABG). 36 other carotid endarterectomies were in patients evaluated cardiologically, but did not require CABG (Isolated group). Risk factors, 30 day perioperative outcome including hospital inpatient stay and early follow-up are reported. RESULTS: The Combined group 30-day perioperative mortality rate was 4.3% and permanent stroke rate 8.6%. There were no major complications in Reverse or Prior staged cases. Isolated group mortality was 2.7% with no strokes. Risk factors were more prevalent in the combined group; 56% previous myocardial infarction, 39% hypertension, 35% a history of raised cholesterol and 46% intermittent claudication. All cases were followed up for a mean of 18.4 months, with no carotid stroke related events. Overall hospital stay for staged patients was a mean 19.3 days (SE=2.4) days compared to mean 9.8 days for combined patients (SE=0.97, p<0.001). CONCLUSIONS: Patients with combined cardiac and carotid disease benefit from assessment of both systems in order to stage CABG and carotid endarterectomy. Risk factors were more prevalent in the combined group; a combined procedure offered a median difference of 8 days less hospital inpatient stay compared to the staged cases. Our experience suggests that carefully planned management of concomitant coronary and carotid disease can achieve better results.

Aged↗
PubMed1999

Gamma-interferon bioassay for detection of bovine tuberculosis in cattle: kinetics of production and dose response in whole blood culture.

Stimulation with Mycobacterium bovis PPD sensitised lymphocytes (whole blood or peripheral blood lymphocytes) results in release of gamma-interferon that can be detected by simple bioassay. The optimum concentration of bovine PPD was 20 micrograms ml and the optimum incubation period was 24 hr for maximum production of gamma-interferon in whole blood culture (128 units/ml) and peripheral blood culture (64 units/ml).

Animals↗
PubMed1998

erbB genes in the mouse uterus: cell-specific signaling by epidermal growth factor (EGF) family of growth factors during implantation.

We previously described spatiotemporal expression of various epidermal growth factor (EGF)-like ligands and receptor subtypes, ErbB1 and ErbB2, during the peri-implantation period. To better understand the roles of these ligands and their possible signaling schemes in implantation, it is important to define the status of all the ligands and receptor subtypes in the uterus/embryo. No information is available about uterine and embryonic status of ErbB3 or ErbB4 during implantation. We cloned mouse erbB3 and erbB4 cDNAs and examined their expression and bioactivity in the peri-implantation uterus (days 1-8). Two erbB3 (cytoplasmic and extracellular) and three erbB4 (two cytoplasmic and one extracellular) clones were generated. Both forms of the erbB3 clone showed similar transcript profiles, while different transcript profiles were obtained with erbB4 clones. The steady-state levels of erbB3 and erbB4 mRNAs in whole uterine poly(A)+ RNA samples showed little changes during the peri-implantation period, while their unique cell-specific accumulation was noted. erbB3 is predominantly expressed in the epithelial cells, although decidual and embryonic cells also accumulate this mRNA. In contrast, the erbB4 mRNA is primarily expressed in the submyometrial stroma and myometrial connective tissues during this period. Additionally, the extracellular form of the erbB4 clone detected signals in a subpopulation of stromal cells. Autophosphorylation and immunoprecipitation studies provided evidence that uterine ErbB3 and ErbB4 are biologically active. This study provides a comprehensive analysis of possible ligand-receptor signaling schemes for EGF-like ligands in implantation.

Animals↗
PubMed1998

A Hindi version of the Diagnostic Interview for Genetic Studies.

The validity of a Hindi version of the Diagnostic Interview for Genetic Studies (DIGS) was investigated. The original English version was initially translated into Hindi. The Hindi version was then back-translated and compared with the original. Next, a group of psychiatric inpatients and outpatients were interviewed using the Hindi version. The resultant diagnoses were compared with those obtained for the same patients using a Hindi version of the Present State Examination (PSE), and the clinical diagnoses given by the treating psychiatrists. The DIGS diagnoses were significantly correlated with both the PSE diagnoses (Cohen's kappa = 0.80) and the clinical diagnoses (kappa = 0.56). Interrater reliability between three interviewers for diagnoses obtained using the Hindi version of the DIGS varied (kappa = 0.45-1.00). Possible causes for this variability are discussed. The Hindi version of the DIGS fulfills the need for a current comprehensive interview schedule not only for psychiatric genetic research in India, but also for nongenetic research.

Adult↗
PubMed1998

Expression of neu differentiation factor during the periimplantation period in the mouse uterus.

Complex cellular interactions occur between the blastocyst and the uterus during implantation. The expression of various polypeptide growth factors and their receptors in the uterus and/or blastocyst during the periimplantation period suggest that growth factors participate in the implantation process. Neu differentiation factor (NDF) is a member of the epidermal growth factor (EGF) family of growth factors and is represented by multiple conserved isoforms. The expression of several EGF-like ligands in the periimplantation uterus has been characterized, including EGF, heparin binding-EGF, transforming growth factor alpha, amphiregulin, betacellulin, and epiregulin. We analyzed the expression pattern of NDF in the periimplantation mouse uterus because of its mitogenic and differentiation-promoting effects. By using Northern analysis and isoform-specific polymerase chain reaction, we found that multiple isoforms are expressed in the periimplantation uterus. NDF displays a highly restricted temporal and spatial expression, with autoradiographic signals localized to the uterine stroma immediately surrounding the implanting blastocyst. NDF expression was absent in mice with delayed implantation but briefly reappeared with the same restricted distribution after termination of the delay by an injection of estrogen. Taken together, these results suggest that an activated blastocyst is required for the expression of NDF and that multiple isoforms may be involved in the complex network of cell-signaling events between the implanting blastocyst and the receptive uterus.

Animals↗
PubMed1998

Regain of fertility and normality of progeny born during below protective threshold antibody titers in women immunized with the HSD-hCG vaccine.

PROBLEM: Phase II clinical trials with the heterospecies dimer of beta hCG and alpha-subunit of ovine luteinizing hormone (HSD)-human chorionic gonadotrophin (hCG) vaccine showed that pregnancy was prevented at and above 50 ng/ml titers, whereas conceptions occurred below 35 ng/ml of hCG bioneutralization capacity. The effect of below-protective threshold anti-hCG antibodies on the progression of pregnancy and the normality of progeny was studied. METHOD OF STUDY: Four women enrolled by informed consent in the Phase II trials. The women studied were immunized with the HCG vaccine and did not receive booster injections in consideration of their desire to have another child. They were examined clinically at least once every month until delivery. The babies were followed up from 2 to 3.5 years, and their anthropometric indices were compared with elder siblings. RESULTS: The pregnancies progressed to 35 to 38 weeks with the usual obstetric problems, and the children developed normally. CONCLUSIONS: The anti-fertility effect of the HSD-hCG vaccine is reversible and low titers of antibodies below the protective threshold have no apparent side effects on the progression of pregnancy and on the early development of the progeny.

Adult↗
PubMed1998

Left ventricular long axis disturbances as predictors for thallium perfusion defects in patients with known peripheral vascular disease.

OBJECTIVE: To compare resting long axis echocardiography with adenosine thallium-201 emission tomography in detecting myocardial ischaemic abnormalities in patients before peripheral vascular surgery. DESIGN: A prospective and blinded preoperative examination of resting left ventricular minor and long axes and myocardial perfusion during adenosine vasodilatation using thallium-201 emission tomography. SETTING: A tertiary referral centre for cardiac and vascular disease equipped with invasive, non-invasive, and surgical facilities. SUBJECTS: 65 patients (40 men) with significant peripheral vascular disease, mean (SD) age 63 (10) years, and 21 control subjects of similar age. METHODS: Segments were classified as normal, with fixed or reversible defects according to thallium-201 myocardial perfusion tomography. Systolic long axis abnormalities were either reduced excursion and/or abnormal shortening after A2, and diastolic abnormalities either delayed onset of lengthening > 80 ms and/or reduced peak lengthening rate < 4.5 cm/s. Segmental perfusion defects were compared with the equivalent long axes; anteroseptal for septal, inferoseptal for posterior, and lateral for left side giving a total of 195 segments. RESULTS: Systolic long axis abnormalities predicted fixed thallium defects (sensitivity 86%, specificity 87%, positive predictive value 0.78, negative predictive value 0.93, p < 0.001), and diastolic abnormalities correlated with reversible perfusion defects (sensitivity 90%, specificity 85%, positive predictive value 0.72, negative predictive value 0.95, p < 0.001). Echocardiography characteristics of the true and false positive segments were not different in the site or the extent of abnormalities. CONCLUSION: Systolic long axis abnormalities predict fixed and diastolic reversible thallium perfusion defects in patients with peripheral vascular disease. Ventricular long axis may thus have a value as a screening test before peripheral vascular surgery as well as providing a means of monitoring myocardial perfusion. The high negative predictive values indicate that a negative long axis study makes significant perfusion abnormalities very unlikely in patients with high pretest probability of coronary artery disease.

Adenosine↗
PubMed1998

Chronic leg pain.

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Chronic Disease↗
PubMed1998

Coordination of differential effects of primary estrogen and catecholestrogen on two distinct targets mediates embryo implantation in the mouse.

In the mouse, estrogen is essential for blastocyst implantation in the progesterone (P4)-primed uterus. The mechanism(s) by which estrogen initiates this response still remains elusive. The present investigation, using delayed implantation in the mouse, examined the differential role of estradiol-17beta (E2) and its catechol metabolite 4-hydroxy-E2 (4-OH-E2) in uterine and blastocyst activation for implantation. The conditions of delayed implantation were induced by ovariectomizing mice on day 4 (day 1 = vaginal plug) of pregnancy or pseudopregnancy and maintaining them with P4 from days 5-7. The binding of EGF to blastocysts was used as a marker for blastocyst activation. Our results show that whereas E2 fails to activate dormant blastocysts (with respect to EGF binding in vitro), 4-OH-E2, cAMP, or prostaglandin E2, is effective in this response. Further, whereas 4-OH-E2 induced-activation is not blocked by an antiestrogen, an inhibitor of PG synthesis, adenylyl cyclase or protein kinase A effectively blocks this activation. These results suggest that 4-OH-E2 effects on blastocysts are mediated by PGs, which, in turn, stimulate cAMP production and thus activation of protein kinase A. Two-fluoro-E2 is a poor substrate and an inhibitor of catecholestrogen synthesis, but it is estrogenic, with respect to uterine growth and gene expression. Using blastocyst transfer experiments, we observed that dormant blastocysts incubated with 4-OH-E2 in vitro, but not with E2, are capable of implanting in P4-treated delayed implanting mice receiving two-fluoro-E2. The results suggest that whereas E2 is necessary for preparation of the uterus, uterine-derived catecholestrogen is important for blastocyst activation for implantation. Indeed, the receptive uterus has the capacity to synthesize 4-OH-E2. Collectively, we demonstrate that the primary ovarian estrogen E2, via its interaction with nuclear estrogen receptors, participates in the preparation of the P4-primed uterus to the receptive state in an endocrine manner, whereas its metabolite 4-OH-E2, produced from E2 in the uterus, mediates blastocyst activation for implantation in a paracrine manner. Our results also establish that these target-specific effects of primary estrogen and catecholestrogen are both essential for implantation and that successful implantation occurs only when the activated stage of the blastocyst coincides with the receptive state of the uterus.

Animals↗
PubMed1998

Differential spatiotemporal regulation of lactoferrin and progesterone receptor genes in the mouse uterus by primary estrogen, catechol estrogen, and xenoestrogen.

Many xenobiotics are considered reproductive toxins because of their ability to interact with the nuclear estrogen receptors (ERalpha and ERbeta). However, there is evidence that these xenobiotics can regulate gene expression in the reproductive targets by mechanisms that do not involve these ERs. To examine this further, we compared the effects of estrogenic (o,p'-DDT [1-(o-chlorophenyl)-1-(p-chlorophenyl)2,2,2-trichloroethane] and Kepone, chlordecone) and nonestrogenic (p,p'-DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane], a metabolite of p,p'-DDT) xenobiotics with those of 17beta-estradiol (E2) and 4-hydroxyestradiol-17beta (4-OH-E2), a catechol metabolite of E2, on uterine expression of lactoferrin (LF) and progesterone receptor (PR). These genes are estrogen responsive in the mouse uterus. Normally, LF is expressed in the uterine epithelium, whereas PR is expressed in both the epithelium and stroma in response to estrogenic stimulation. Ovariectomized mice were injected with xenobiotics (7.5 mg/kg), E2 (10 microg/kg), 4-OH-E2 (10 microg/kg), or the vehicle (oil, 0.1 ml/mouse), and uterine tissues were processed for Northern blot and in situ hybridization. The pure antiestrogen ICI-182780 (ICI; 1 or 20 mg/kg) was used to interfere with estrogenic responses that were associated with the ERs. The results of Northern and in situ hybridization demonstrated increased uterine levels of PR and LF messenger RNAs (mRNAs) by all of these xenobiotics, but quantitatively the responses were much lower than those induced by E2 or 4-OH-E2. The results further showed that the E2-inducible epithelial LF mRNA accumulation was markedly abrogated by pretreatment with ICI (20 mg/kg). In contrast, this treatment retained the epithelial expression of PR mRNA, but down-regulated the stromal expression. In contrast, ICI had negligible effects on LF and PR mRNA responses to 4-OH-E2, indicating that this catechol estrogen exerted its effects primarily via a mechanism(s) other than the ERs. The heightened accumulation of LF mRNA in the epithelium in response to Kepone and o,p'-DDT was also severely compromised by pretreatment with ICI, but this antiestrogen had little effect on responses to p,p'-DDD. Similar to E2, Kepone increased the expression of PR mRNA in both uterine epithelium and stroma. However, pretreatment with ICI decreased stromal cell expression, whereas epithelial cell expression remained unaltered or increased. These responses were not noted in mice treated with o,p'-DDT or p,p'-DDD. Collectively, the results demonstrate that catechol estrogens or xenobiotics can alter uterine expression of estrogen-responsive genes by mechanisms that are not totally mediated by the classical nuclear ERs, and these alterations are cell type specific. We conclude that an interaction of a compound with the nuclear ERalpha and/or ERbeta is not an absolute requirement for producing specific estrogen-like effects in the reproductive target tissues.

Animals↗
PubMed1998

Histidine decarboxylase gene in the mouse uterus is regulated by progesterone and correlates with uterine differentiation for blastocyst implantation.

Cell-cell interactions between the blastocyst trophectoderm and uterine luminal epithelium are essential to the process of implantation. The factors that participate in these interactions or their mechanism of actions are poorly understood. Histamine has long been suspected as one of the factors that is involved in implantation. Histamine is formed from L-histidine by histidine decarboxylase (HDC). We examined the expression and regulation of HDC gene in the mouse uterus during early pregnancy and under steroid hormonal stimulation. Northern blot hybridization detected a 2.6-kb transcript of HDC messenger RNA (mRNA) in uterine poly(A)+ RNA samples. Maximum uterine accumulation of HDC mRNA occurred on days 3 and 4 of pregnancy, followed by marked declines on later days (days 5-8). In ovariectomized mice, uterine mRNA levels were up-regulated by an injection of progesterone (P4) by 6 h, and the levels were maintained through 24 h. In contrast, an injection of estradiol-17beta neither stimulated nor antagonized P4-induced HDC mRNA accumulation. P4-induced up-regulation was considerably abrogated by pretreatment with RU-486, a P4 receptor antagonist, suggesting involvement of P4 receptor. In situ hybridization detected HDC mRNA specifically in uterine epithelial cells but not in other cell types. Again, high epithelial accumulation occurred on day 4 of pregnancy. With the progression of implantation (days 5-8), HDC mRNA levels declined in the luminal epithelium surrounding the implanting blastocysts, as compared with that away from the blastocysts. Immunoreactive histamine and HDC were colocalized with HDC mRNA. Western blotting detected a 54-kDa protein in epithelial cell extracts, which also exhibited HDC activity. Expression of HDC in epithelial cells, preceding implantation on day 4, at lower levels after initiation of implantation on day 5, and its regulation by P4 suggest that this gene plays an important role in implantation.

Animals↗
PubMed1998

Clinical profile of myasthenia gravis.

Seventy three patients with myasthenia gravis were studied over 9 years period (1987-1995) in departments of neuromedicine, respiratory care unit, cardiothoracic unit of Institute of Postgraduate Medical Education and Research and Bangur Institute of Neurology, Calcutta, with reference to their clinical presentations, laboratory findings and various modes of treatment. Commonest age of presentation was 5th decade in men and 3rd decade in women. Fifty five percent of patients belong to type 2A myasthenia gravis (Osserman classification). Presentation was insidious (67.2%) and course was slowly progressive (65.7%) in majority of cases. Fatigability and ptosis were commonest clinical presentation and diurnal variation was noticed in 60% of cases. Edrophonium test was positive in 90.4% of cases and repetitive nerve stimulation showed 93.5% positivity in 30 cases. 27 patients (36.9%) underwent thymectomy and out of these, 89% of patients showed hyperplastic change and thymoma in 11% of cases. Mortality rate including both operated and nonoperated patients was recorded to be 9.6%. We observed earlier onset of myasthenia in male, higher incidence of oculo-bulbar involvement and lower incidence of respiratory problem and thymoma.

Adolescent↗
PubMed1998

Cytohormonal evaluation of vaginal smears by phase contrast microscopy with special reference to progesterone deficiency pattern during early pregnancy as predictor of abortion.

Cytohormonal profile of unstained vaginal smears were studied under phase contrast microscope to define various cell morphologies in detail and build up of smear pattern serially in various stages of menstrual cycle and first trimester of pregnancy. The findings were correlated clinically and found comparable to Papanicolaou stained smears. The maturation index was calculated more objectively by phase contract microscopy because of the refractile appearance of the pyknotic nuclei of superficial cells. The prognostication of abortion was done by combining abnormal maturation index and the presence of syncytiotrophoblasts in vaginal smears. Under phase contrast microscope, the sensitivity of abnormal smear was 87.5%, the specificity was 95%, the positive predictive value was 96.55% and the overall accuracy was 90% as compared to positive Papanicolaou smear whose sensitivity though 93%, had low specificity of 50% only. Phase contrast study appears to offer certain distinct advantage over the conventional light microscopy for quick, comprehensive and quantitative assessment of the study material. It allows the physician to detect changes in the material obtained from the patients without detour of laboratory fixation and staining. It is technically easy as errors in interpretation due to unsatisfactory fixation, staining and artefacts are obviated. Thus phase contrast microscopy offers an alternative and easy method of cytohormonal evaluation of wet and unstained smears.

Abortion, Threatened↗