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S Mittal

Publications and source records attributed to S Mittal.

At least 73 records · Page 4Linked to original sources
PubMed1999

Mononuclear cell-modulation of granulosa cell steroidogenesis in rat: influence of ovarian cycle.

The mononuclear cells exert a paracrine influence on the ovarian function, including steroidogenesis. This study examines the ability of the conditioned medium from the cultures of splenic mononuclear cells, obtained during various phases of the ovarian cycle, on progesterone accumulation by the granulosa cells in the culture medium. Female Wistar rats, aged twenty-five days, were made pseudopregnant by an injection of pregnant mare's serum gonadotropin. The splenic mononuclear cells were isolated at follicular phase, early luteal phase, mid luteal phase and late luteal phase and cultured for 48 h. The ammonium sulphate precipitated fraction of the conditioned medium was added to the granulosa cells obtained from immature rats treated with diethylstillboestrol. The granulosa cells were cultured for 48 h, and the progesterone accumulated in the medium was assayed. The conditioned medium from the cultures of the mononuclear cells obtained during follicular phase and late luteal phase inhibited FSH-induced progesterone secretion, whereas conditioned medium obtained from mid luteal phase mononuclear cells enhanced the effect of FSH. The stimulatory effect of db-cAMP on progesterone accumulation in the culture medium is inhibited by conditioned medium obtained from all the phases of the ovarian cycle. This study demonstrates a cyclicity in the behaviour of the splenic mononuclear cells on ovarian steroidogenesis, suggesting a bi-directional paracrine and/or endocrine relationship between ovary and the mononuclear cells.

Animals↗
PubMed1999

Catecholamine facilitated reentrant ventricular tachycardia: uncoupling of adenosine's antiadrenergic effects.

INTRODUCTION: Adenosine has no direct electrophysiologic function in ventricular tissue, but in the presence of cyclic adenosine monophosphate (cAMP), stimulation exerts a potent antiadrenergic effect. This effect has been exploited in the recognition and treatment of ventricular tachycardia (VT) due to cAMP-mediated triggered activity and automaticity, which are respectively terminated and suppressed by adenosine. However, the effects of adenosine on catecholamine-facilitated reentrant VT are unknown. A pivotal issue is whether termination of VT with adenosine is mechanism specific, or whether it represents a nonspecific antiadrenergic effect. The purpose of this study, therefore, was to define the effects of adenosine in a well-characterized group of patients with catecholamine-facilitated reentrant VT. METHODS AND RESULTS: Fourteen patients with catecholamine-facilitated reentry were studied. In the 12 patients with structural heart disease (including two with arrhythmogenic right ventricular dysplasia), adenosine (260 to 550 microg/kg) failed to slow or terminate VT. Two patients without structural heart disease had intrafascicular tachycardia confined to the left posterior fascicle, a calcium-dependent, verapamil-sensitive arrhythmia. In the absence of isoproterenol, verapamil terminated VT but adenosine did not. However, when isoproterenol was subsequently required for facilitation of tachycardia, adenosine terminated VT in both patients. CONCLUSION: Adenosine has no antiadrenergic (antiarrhythmic) effect in patients with catecholamine-facilitated VT due to structural heart disease. Patients with verapamil-sensitive, left posterior intrafascicular reentry have an unusual dual response to adenosine. In the unstimulated state, adenosine has no effect on basal inward calcium current and, therefore, no effect on VT. However, when induction of VT requires amplification of the inward calcium current through stimulation of cAMP, adenosine sensitivity of VT becomes manifest. These results indicate that with few exceptions, termination of VT with adenosine is strongly suggestive of a cAMP-mediated triggered mechanism rather than reentry.

Adenosine↗
PubMed1999

Differential effects of adenosine on focal and macroreentrant atrial tachycardia.

INTRODUCTION: The effects of adenosine on atrial tachycardia (AT) remain controversial, and the mechanistic implications of adenosine termination have not been fully established. The purpose of this study was to elucidate the differential effects of adenosine on focal and macroreentrant AT and describe the characteristics of adenosine-sensitive AT. METHODS AND RESULTS: Thirty patients received adenosine during AT. Tachycardia origins were identified as focal or macroreentrant during invasive electrophysiologic studies. Responses to adenosine were analyzed and characterized as tachycardia termination, transient suppression, or no effect. Electrophysiologic studies demonstrated a focal origin of tachycardia in 17 patients. Adenosine terminated focal tachycardias in 14 patients (dose 7.3 +/- 4.0 mg) and transiently suppressed the arrhythmias in three others (dose 10.0 +/- 6.9 mg). A macroreentrant mechanism was demonstrated in 13 patients; adenosine terminated only one of these tachycardias and had no effect on the remaining 12 patients (dose 10.2 +/- 2.9 mg). Four classes of adenosine-sensitive AT were identified. Class I consisted of nine patients with tachycardia arising from the crista terminalis; these tachycardias also terminated with verapamil (4/4). Class II consisted of four patients with repetitive monomorphic AT arising from diverse sites in the right atrium; these either slowed or terminated in response to verapamil (2/2). Class III consisted of the three patients with transient suppression and demonstrated electropharmacologic characteristics consistent with an automatic mechanism, including insensitivity to verapamil (2/2). In the one patient with macroreentrant AT that was comprised of decremental atrial tissue, adenosine terminated tachycardia in a zone of decremental slow conduction (Class IV); this tachycardia slowed with verapamil. CONCLUSIONS: Adenosine-sensitive AT is usually focal in origin and arises either from the region of the crista terminalis (inclusive of the sinus node) or from diverse atrial sites with an incessant nonsustained repetitive pattern. Although most forms of macroreentrant AT are insensitive to adenosine, rarely macroreentrant AT with zones of decremental slow conduction can demonstrate adenosine sensitivity.

Adenosine↗
PubMed1999

Cytological study of serous effusions with the aid of tumour markers.

Clinicocytological evaluation with the help of tumour markers was done in 25 cases presenting with serous effusions. The main aim was to differentiate between reactive mesothelial cells and malignant cells, type the tumour cells in effusions with the aid of tumour markers--carcino-embryonic antigen (CEA), epithelial membrane antigen (EMA), cytokeratin and vimentin. It was observed that immunocytochemistry has complemented conventional cytology in diagnosis of carcinoma specially in cases labelled as suspicious of malignancy. EMA was found to be the most reliable epithelial marker and very useful in differentiating carcinoma cells from reactive mesothelial cells.

Abdominal Neoplasms↗
PubMed1998

Mammary coronary artery anastomosis without cardiopulmonary bypass through minithoracotomy: one year clinical experience.

OBJECTIVE: The recent concept of minimally invasive coronary artery surgery in selected patients has dramatically affected surgical management of coronary artery disease. We explored the possibility of coronary artery bypass grafting of anterior coronary arteries with in situ internal mammary artery through a limited anterior thoracotomy on beating heart. METHOD: Minithoracotomy and direct coronary artery surgery without cardiopulmonary bypass (CPB) was attempted in 116 patients. The procedure was completed in 108 cases while in eight cases minithoracotomy was converted to mid sternotomy. In 107 cases, left internal mammary artery (LIMA) to left anterior descending (LAD) coronary artery anastomosis was done through left anterior minithoracotomy and in one case LIMA to LAD and right internal mammary artery (RIMA) to right coronary artery (RCA) anastomosis was done through bilateral minithoracotomy. Left anterior minithoracotomy through 4th intercostal space and right anterior minithoracotomy through 5th intercostal space was used for left and right internal mammary artery dissection respectively. With this approach 4-8 cm length of mammary artery was easily dissected. Mammary coronary artery anastomosis were performed on a beating heart without CPB through window pericardiotomy. Two patients also underwent left carotid endarterectomy along with LIMA to LAD anastomosis. In two patients complementary percutaneous transluminal coronary angioplasty (PTCA) to circumflex artery was done 5 days after minithoracotomy and LIMA to LAD anastomosis. RESULTS: Forty-two patients were extubated in the operating room and 66 in the intensive care unit 2-10 h after surgery. Blood transfusion was used in one case who was reexplored for postoperative bleeding due to a displaced hemoclip from the internal mammary artery branch. None of these patients required inotropic support. Postoperative predischarge check angiogram in 53 cases revealed adequate mammary coronary flow in 51 cases, the remaining two had anastomotic problems, one was subjected to PTCA and the other for redo coronary bypass grafting through mid sternotomy. Doppler flow assessment of anastomosis was done in 102 cases, of which two showed problems which was confirmed on check angiography. One-hundred and six patients are in our regular follow-up (mean follow-up 10+/-1.5 months), 98 of them are in functional class I. CONCLUSION: In our experience mammary coronary artery anastomosis without CPB through minithoracotomy is a safe, simple and minimally invasive procedure. Favorable cost/benefit ratio, has been achieved due to no early/late mortality and minimal early morbidity. Postoperative check angiogram and Doppler flow study revealed excellent mid term results.

Cardiopulmonary Bypass↗
PubMed1998

Posterior scleritis: clinical profile and imaging characteristics.

Posterior scleritis is relatively uncommon and is often misdiagnosed due to its protean manifestations. We report eight cases of posterior scleritis to analyse the clinical profile, ultrasonographic and computed tomography (CT) scan features of this rare disorder. Fundus findings included serous retinal detachment, choroidal folds, retinal folds, subretinal mass, choroidal detachment, disc edema, and macular edema. There was associated anterior scleritis and anterior uveitis in the majority of the cases. In all cases ultrasound with or without CT scan confirmed the clinical diagnosis. All patients responded to systemic steroids except one who required immunosuppressive therapy. This paper describes the clinical profile of a series of posterior scleritis cases highlighting varied clinical presentation, and the role of ultrasound and CT scan findings in the diagnosis.

Adolescent↗
PubMed1998

Evaluation of endothelial function in postkeratoplasty eyes.

BACKGROUND AND OBJECTIVE: To evaluate corneal endothelium function in postkeratoplasty eyes. PATIENTS AND METHODS: Endothelial function was assessed in 23 clear corneal grafts. After a measurable corneal edema was induced by soft contact lens wear, serial pachometric readings were taken for 3 hours to arrive at the percentage recovery per hour (PRPH) index. RESULTS: The assessed PRPH values of the clear corneal grafts ranged from 24.6% to 73.0%, with a mean value of 51.8% +/- 12.2%. Of the six corneal grafts that demonstrated an initial PRPH value of less than 47.5%, four became edematous within 6 months of follow-up. CONCLUSIONS: Assessed PRPH, as an in vivo-measured index of endothelial function, is a valuable method for monitoring endothelial function in postkeratoplasty eyes. The low PRPH index identifies eyes at risk of spontaneous nonimmunologic failures.

Corneal Edema↗
PubMed1998

Primary amenorrhoea: analysis of 48 cases.

The clinical analysis of 48 patients of primary amenorrhoea seen at All India Institute of Medical Sciences, New Delhi for a period of 3 years, was performed. Twenty-six patients (54.2%) had muellerian anomalies, 11 (22.9%) had hypogonadotropic hypogonadism, 8 (16.6%) had hypergonadotropic hypogonadism and 3 (6.3%) had genital tuberculosis. The study highlights the role of transabdominal sonography in the work up of these cases. It suggests the reproductive potential of these cases by visualising the genital organs and makes laparoscopy and intravenous pyelography obsolete and selects the cases who deserve to be further investigated.

Adolescent↗
PubMed1998

Correlation of radiological and pathological assessment of tumour volume with lymph node involvement in cancer cervix.

The present study was carried out in 18 patients with carcinoma cervix stage IB through early IIB-Preoperative computerised tomography (C.T.) was done within seven days before surgery. Volume of tumour was determined from the C. T. films. Radical hysterectomy Type-III was performed in all 18 patients and specimens of cervix, parametrium and lymph nodes subjected to histopathological examination. Each specimen of cervix was cut into 4 to 12 equal sections depending on the size of the tumour mass. Cervical tumour volume was measured. Correlation of radiological with pathological tumour volume and of tumour volume with lymph node involvement was done. C. T. Scan was able to detect tumour mass accurately only four patients (Sensitivity 40%, Specificity 28.5%). In the Indian setting the conventional surgical approach appears to be the more appropriate.

Adult↗
PubMed1997

Comparison of outcome after stenting for de novo versus restenotic narrowings in native coronary arteries.

Intracoronary stenting of de novo narrowings results in a lower restenosis rate when compared with percutaneous transluminal coronary angioplasty. We sought to determine whether intracoronary stenting for restenotic narrowings is associated with a worse outcome when compared with stenting for de novo narrowings. A total of 114 consecutive patients with 124 narrowings were retrospectively identified. Stents were deployed in 46 de novo (37%) and in 78 restenotic (63%) narrowings. The 2 groups were similar with respect to variables known to affect restenosis. Follow-up angiograms were available in 88% of patients at a mean of 6.3 +/- 3.3 months after stent implantation. At follow-up angiography, a significantly higher restenosis rate in the restenotic group was observed (p = 0.05). Restenosis risk could not be predicted from variables known at the time of stent implantation. However, the presence of angina at the time of follow-up was significantly associated with restenosis (p = 0.01). Kaplan-Meier survival curves for freedom from repeat target-site revascularization demonstrated a significant difference in the need for target-site revascularization between the de novo and restenotic groups over the first-year post-stent implantation (p = 0.01; relative risk = 1.94). Multivariate analysis identified restenosis as the indication for stenting (p <0.01), postprocedure percent stenosis (p = 0.01), and narrowing length (p = 0.01) as independent predictors for repeat target-site revascularization. When compared with de novo narrowings, restenotic narrowings have a worse outcome after stenting. A prospective, randomized trial comparing outcome after percutaneous transluminal coronary angioplasty and stents for restenotic narrowings would be useful.

Adult↗
PubMed1997

Mammary-coronary artery anastomosis without cardiopulmonary bypass through a minithoracotomy.

BACKGROUND: Coronary artery bypass grafting has been based on cardiopulmonary bypass, myocardial protection, and the median sternotomy. The recent concept of minimally invasive coronary artery bypass grafting in selected patients has dramatically affected surgical management of coronary artery disease. Coronary artery bypass grafting of anterior coronary arteries with in situ internal mammary artery through a limited anterior thoracotomy is a procedure that is gaining acceptance. METHODS: Fifty-one patients were operated on by minithoracotomy and direct coronary artery bypass grafting without cardiopulmonary bypass. Left internal mammary artery-to-left anterior descending coronary artery anastomosis was done in 50 patients, and in 1 patient, left internal mammary artery-to-left anterior descending artery and right internal mammary artery-to-right coronary artery anastomoses were constructed through bilateral minithoracotomies. Left anterior minithoracotomy through the fourth intercostal space and right anterior minithoracotomy through the fifth intercostal space were used for left internal mammary artery and right internal mammary artery dissection, respectively. With this approach, a 4- to 6-cm length of mammary artery was easily dissected. Mammary-to-coronary anastomosis was performed on a beating heart without cardiopulmonary bypass through window pericardiotomy. RESULTS: Twenty-five patients were extubated in the operating room and 26 in the intensive care unit 4 to 6 hours after operation. None of these patients required blood transfusion or inotropic support. Postoperative predischarge angiography in 42 patients revealed adequate mammary-to-coronary flow in 40 patients. Doppler flow studies were also in accordance with angiographic findings. Forty-five patients are in our regular follow-up (mean follow-up, 6.23 +/- 1.34 months); 44 of them are in functional class I. CONCLUSION: In our experience minithoracotomy is a safe, simple, and minimally invasive procedure. Favorable cost/benefit ratio has been achieved owing to no early or late mortality and minimal early morbidity. Postoperative angiography and Doppler flow study revealed excellent predictive long-term results.

Adult↗
PubMed1997

Diagnosis of a persistent coronary fistula after ventricular septal defect patch closure.

Penetrating chest trauma can result in multiple clinical syndromes depending on the structures involved. Tamponade, valvular regurgitation, ventricular septal defect (VSD), conduction system abnormalities, and coronary lacerations have been reported. We report a case of right ventricular free wall laceration, VSD, and coronary artery fistula involving a septal perforator.

Adult↗
PubMed1997

Sustained bundle branch reentry in a patient with hypertrophic cardiomyopathy and nondilated left ventricle.

Ventricular tachycardia is a well-known complication in patients with hypertrophic cardiomyopathy. We report the case of a patient with hypertrophic cardiomyopathy with easily inducible monomorphic ventricular tachycardia. Electrophysiology study demonstrated that bundle branch reentry was the mechanism of the tachycardia. The tachycardia was rendered non-inducible by radiofrequency ablation of the right bundle branch.

Adult↗
PubMed1997

An interesting unusual case of endometrial stromal sarcoma.

An interesting case with an unusual presentation of endometrial sarcoma is described. This patient presented with a history of continuous vaginal bleeding 3 months following a full term caesarean section and perception of an enlarging abdominal mass. The physical examination revealed an enlarged uterus with a leiomyoma though there was no evidence of the same at the time of the caesarean section. A laparotomy was undertaken and the patient was found to have a large tumor with multiple polypoidal growths invading the myometrium through to the serosa. This was proven to be an endometrial stromal sarcoma on histopathology.

Adult↗