Search PubMed⌕ Search

Biomedical subjects

S Sharma

Publications and source records attributed to S Sharma.

At least 1,513 records · Page 84Linked to original sources

Suppression of bioactive luteinizing hormone and testosterone by a progesterone antagonist ZK 98.734 in adult male common marmosets, Callithrix jacchus.

The effects of a progesterone antagonist ZK 98.734 on release of bioactive luteinizing hormone (LH) and testosterone were studied in adult male common marmosets by using the following experimental protocols: (1) the blocking of the nocturnal rise in testosterone levels by ZK 98.734, (2) the pharmacodynamic effects of ZK 98.734 on testosterone and LH levels, (3) the reversal of ZK 98.734-induced decrease in testosterone by treatment with human chorionic gonadotropin (hCG), and (4) the blocking of estradiol-induced positive feedback release of LH by ZK 98.734. Sixteen adult male common marmosets were used for different experiments after resting them for at least 4 wk between experiments. Testosterone and bioactive LH levels were measured by specific radioimmunoassay and in vitro bioassay methods, respectively. Treatment (i.m.) of male common marmosets (n = 6/group) with ZK 98.734 (1 mg or 5 mg/day) at 1700 h for 3 consecutive days significantly (p less than 0.05) suppressed the nocturnal (2200 h) rise in testosterone levels. The effects of the two doses were not dose-related; however, the decrease on the first day of treatment was more pronounced with the 5-mg dose than with the 1-mg dose. Diurnal rhythms were restored during the post-treatment period. Similarly, treatment with ZK 98.734 (5 mg, n = 8/group) at 1000 h caused a decrease in testosterone and LH levels. The levels were significantly (p less than 0.05) lower at 3 and 6 h after treatment compared to pretreatment levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Iron overload and iron-chelating therapy in hemoglobin E-beta thalassemia.

Whereas hemoglobin (Hb) E-beta thalassemia is recognized as probably the most common serious hemoglobinopathy worldwide, its natural history remains poorly defined. The interaction of hemoglobin E and beta-thalassemia result in a wide spectrum of clinical disorders, some indistinguishable from thalassemia major and some milder and not transfusion-dependent. Partially as a result of this wide range of phenotypes, clear guidelines for approaches to transfusion and to iron-chelating therapy for patients with Hb E-beta thalassemia have not been developed. By contrast, data that have accumulated during the past 10 years in patients with beta-thalassemia permit a quantitative approach to the management of iron overload and provide guidelines for the control of body iron burden in individual patients treated with iron-chelating therapy. These guidelines may be applicable to patients with Hb E-beta thalassemia. Preliminary evidence from our studies of iron loading in affected patients with Hb E-beta thalassemia in Sri Lanka suggest that this disorder may be associated with variable, but accelerated, gastrointestinal iron absorption, and that the iron loading associated with chronic transfusions in patients with Hb E-beta thalassemia is similar to that observed in patients with beta-thalassemia. These data, in the only cohort of patients with Hb E-beta thalassemia to have undergone quantitative assessment of body iron burden, suggest that the principles that guide assessment of iron loading and initiation of chelating therapy in patients with beta-thalassemia may be generally applicable to those with Hb E-beta thalassemia. Further quantitative studies in both nontransfused and transfused patients will be necessary to permit firm conclusions.

Adult↗

Value of exercise testing in assessing clinical state and prognosis in hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a genetic disease of the sarcomeric contractile proteins. A majority of patients with HCM are limited in terms of functional capacity, and a minority of these patients die suddenly. The main aims of management are symptom alleviation and prevention of sudden cardiac death. In patients with HCM, cardiopulmonary exercise testing provides a much more accurate index of functional capacity than New York Heart Association classification status, and it is useful in assessing symptoms after various therapeutic strategies have been implemented. Exercise testing is also valuable in identifying patients with HCM who are at high risk of sudden cardiac death and is an integral part of the algorithm in risk stratification and delivery of prophylactic therapy. Also, cardiopulmonary exercise testing plays an important role in differentiating HCM from other conditions associated with left ventricular hypertrophy, such as physiologic athlete's heart. Therefore, during the last few years, cardiopulmonary exercise testing has provided insights into the diagnosis, determinants, and mechanisms of exercise limitation in HCM. This understanding aids physicians in targeting therapy and developing new treatment modalities.

Cardiomyopathy, Hypertrophic↗

Transient abnormality in carbohydrate metabolism during enterically transmitted non-A, non-B acute viral hepatitis.

Blood glucose, plasma insulin and free fatty acids (FFA) responses, during the 2 h oral glucose tolerance test (OGTT) with 75 g of dextrose, were measured in 30 consecutive patients with acute enterically transmitted non-A, non-B hepatitis. All of these parameters during the OGTT were compared with 10 age-, sex- and weight-matched healthy volunteers from the same community. The fasting blood sugar, insulin and FFA were not different from normal controls (P greater than 0.05). According to the WHO criteria, the blood glucose response during OGTT in these patients was normal in 23%, impaired in 33% and diabetic in 43%. There was significant hyperinsulinaemia (P less than 0.001) in patients with impaired and diabetic GGT and it persisted even at the end of 2 h. None of the abnormal liver function tests correlated with blood sugar, insulin and FFA response during the OGTT. All abnormal responses during the OGTT were, however, transient and returned to normal in all the patients after the recovery from acute hepatitis.

Adult↗

The quality of life of patients with hypertension.

The authors evaluated the self-reported quality of life in patients with systemic arterial hypertension and assessed whether clinicians and normotensive respondents from the general public appreciate the impact that hypertension has on health-related quality of life. A quality-of-life questionnaire was completed by 385 individuals: persons with hypertension (n=188), normotensive persons (n=148), and clinicians (n=49). A utility score, which represents one's self-perceived health-related quality of life, was generated for each group by using standardized time tradeoff questionnaires. Quality of life with hypertension was judged to be significantly higher according to affected individuals (mean utility score, 0.980), compared with normotensive persons (mean utility score, 0.948) and clinicians (mean utility score, 0.942), who were asked to assume that they had hypertension (p<0.0005). Clinicians and normotensive individuals tend to overemphasize the impact that hypertension has on quality of life, as compared to affected patients. The relatively low impact that hypertensive individuals indicate high blood pressure has on their quality of life may contribute to their lack of compliance with treatment regimens.

Adaptation, Psychological↗

Pelvic exenterations for gynecological malignancies: twenty-year experience at Roswell Park Cancer Institute.

The objective of this study is to review the experience with pelvic exenterations for gynecological malignancies at our cancer institute. Charts of 48 women who underwent a pelvic exenteration between January 1980 and December 1999 were reviewed, and several outcomes were analyzed. Majority of patients had received prior radiation therapy. The median survival was 35 months, and the disease-free survival was 32 months. Mortality from the procedure was 4.2%. Early and late postoperative complication rates were 27% and 75%, respectively. Recurrence rate was 60%. Eight patients received intraoperative radiation. Median survival in this group was 11.3 vs 35 months (P = 0.003). Univariate analysis failed to show an association between type of pelvic exenteration, type of fecal and urinary diversion, outcome, need for reoperation, and recurrence. Contemporary pelvic exenterations are associated with a low mortality and a potential for long-term survival in a subset of patients who historically have been given a poor prognosis. In patients with recurrent gynecological cancer confined centrally to the pelvis, pelvic exenteration still remains the choice of therapy as response to chemotherapy to a centrally recurrent tumor in radiated area continues to be poor. Intraoperative radiation in select few patients needs to be further studied.

Adult↗

Cardiac surgery in nonagenarians.

OBJECTIVES AND BACKGROUND: The purpose of this study was to document our initial experience with patients 90 years of age and older and to determine whether cardiac surgery is justified in this age group. Cardiac surgery in octogenarians has proven to be a successful and worthwhile procedure. A small group of nonagenarians with severe coronary artery disease (CAD) and aortic valve disease refractory to medical therapy have been considered for surgery. METHODS: Fourteen patients aged 90 or more underwent cardiac surgery for symptomatic CAD or aortic valvular disease refractory to medical therapy. Eight patients underwent isolated coronary artery bypass grafting (CABG) and six patients underwent aortic valve replacement (AVR). All patients were in NYHA Class IV preoperatively. RESULTS: Hospital mortality occurred in one patient (7%). Hospital morbidity occurred in 10 patients (71%) and included 7 cardiac, 5 neurological, 1 gastrointestinal, 1 infectious, and 1 pulmonary event. All survivors left the hospital symptomatically improved. The mean length of stay was 26 days. Four CABG patients went on to die at a mean of 2 years and 2 months, and 3 remain alive at a mean of 2 years and 4 months. Three AVR patients expired at a mean of 3 years and 4 months, and 3 remain alive at 4 years and 1 month. CONCLUSIONS: Cardiac surgery in carefully selected nonagenarians is justified and can be performed with acceptable results.

Aged↗

Coronary artery bypass grafting in patients with chronic renal failure: A reappraisal.

BACKGROUND AND AIMS: Chronic renal failure (CRF) is known to increase the morbidity and mortality in patients undergoing cardiac operations. Successful outcome of coronary artery bypass grafting (CABG) in some patients with CRF has been reported, but remains controversial. METHODS: Forty-four patients with CRF who underwent CABG were examined. Two groups were analyzed. Group I consisted of 13 patients with end-stage renal disease on hemodialysis. Group II consisted of 31 patients with a creatinine > or = 1.6 gm/dL for a minimum of 6 months, but were not on dialysis. There were 36 male and 8 female patients, with a mean age of 71 years. RESULTS: The hospital mortality was 10 patients (23%) with 4 (31%) hospital deaths in Group I, and 6 (19%) in Group II. There was major morbidity in 35 (80%) patients. In Group II there were 8 (26%) patients who required permanent postoperative dialysis. A control group of 547 patients 70 years of age who underwent CABG had 30 hospital mortalities (5%) and 75 morbidities (13%). The average length of stay was 27 days. Fifteen patients died at a mean of 34 months after being discharged from the hospital. Nineteen of the original 44 patients remain alive at a mean of 32 months. The total mortality at 6 years and 4 months was 57%. CONCLUSIONS: Older and sicker patients with CRF who undergo CABG are at an exceptionally high risk for mortality and morbidity. For CRF patients not on dialysis with a creatinine 2.5 gm/dL, there is a strong likelihood of permanent postoperative dialysis. Long-term follow-up shows survival to be well below their non-CRF counterparts.

Age Factors↗

Coronary artery bypass grafting in patients in their third decade of life.

BACKGROUND AND AIM: Coronary artery disease (CAD) and coronary artery bypass grafting (CABG) in young patients are different than their older counterparts. The purpose of this study is to more fully define the issues of CABG in patients in their third decade of life. METHODS: The medical records from all patients under forty years of age undergoing CABG at Allegheny University Hospital, Hahnemann Division, Philadelphia, PA from July 1990 to June 1995 were examined. Surgical outcome, psychosocial, and sexual issues were examined. Lipid analyses were compared perioperatively. RESULTS: There were 43 male and 9 female patients. The mean age was 35 years (23 to 39 years). Risk factors included 43 (83%) patients with a history of smoking, 34 (65%) with familial hypercholesterolemia, 25 (48%) with a family history of CAD, 23 (44%) with hypertension, and 11 (21%) with diabetes. The mean preoperative serum cholesterol was 241 mg/dL. There were no hospital mortalities. Morbidities were found in 18 (35%) patients, including 9 (17%) cardiac, 5 (10%) pulmonary, 3 (6%) infectious, and 1 (2%) renal. In follow-up, three cardiac-related mortalities occurred within five years of surgery. Sixteen patients were readmitted to a hospital for cardiac related causes. Thirty-two (62%) patients failed to return to work, twenty-five (48%) failed to engage in regular exercise, and twenty-four resumed smoking. Psychosocial changes were found postoperatively in thirty (58%) patients. Eight (15%) patients admitted to sexual changes following surgery. Postoperative lipid profiles were minimally altered from preoperative values. CONCLUSIONS: Surgical revascularization is successful in alleviating symptoms with minimal risk. Postoperatively, a number of cardiac related events occurred. A significant number of patients resume smoking, fail to engage in regular exercise, fail to resume work, and fail to take prescribed lipid-lowering agents. Psychosocial and sexual dysfunctions are prominent.

Adult↗

Mycotic pulmonary arterial aneurysms in an intravenous drug user.

A case of mycotic pulmonary artery aneurysm (PAA) in an intravenous drug user in whom resolution occurred with conservative therapy is described. The natural history of PAA is not well described in the literature. Although PAA is potentially fatal, resolution may occur in patients who do not have hemoptysis. Clinical presentation, diagnosis and management of PAA are reviewed.

Adult↗

Ubiquinone (coenzyme q10) and mitochondria in oxidative stress of parkinson's disease.

Parkinson's disease is the second most common neurodegenerative disorder after Alzheimer's disease affecting approximately1% of the population older than 50 years. There is a worldwide increase in disease prevalence due to the increasing age of human populations. A definitive neuropathological diagnosis of Parkinson's disease requires loss of dopaminergic neurons in the substantia nigra and related brain stem nuclei, and the presence of Lewy bodies in remaining nerve cells. The contribution of genetic factors to the pathogenesis of Parkinson's disease is increasingly being recognized. A point mutation which is sufficient to cause a rare autosomal dominant form of the disorder has been recently identified in the alpha-synuclein gene on chromosome 4 in the much more common sporadic, or 'idiopathic' form of Parkinson's disease, and a defect of complex I of the mitochondrial respiratory chain was confirmed at the biochemical level. Disease specificity of this defect has been demonstrated for the parkinsonian substantia nigra. These findings and the observation that the neurotoxin 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP), which causes a Parkinson-like syndrome in humans, acts via inhibition of complex I have triggered research interest in the mitochondrial genetics of Parkinson's disease. Oxidative phosphorylation consists of five protein-lipid enzyme complexes located in the mitochondrial inner membrane that contain flavins (FMN, FAD), quinoid compounds (coenzyme Q10, CoQ10) and transition metal compounds (iron-sulfur clusters, hemes, protein-bound copper). These enzymes are designated complex I (NADH:ubiquinone oxidoreductase, EC 1.6. 5.3), complex II (succinate:ubiquinone oxidoreductase, EC 1.3.5.1), complex III (ubiquinol:ferrocytochrome c oxidoreductase, EC 1.10.2.2), complex IV (ferrocytochrome c:oxygen oxidoreductase or cytochrome c oxidase, EC 1.9.3.1), and complex V (ATP synthase, EC 3.6.1.34). A defect in mitochondrial oxidative phosphorylation, in terms of a reduction in the activity of NADH CoQ reductase (complex I) has been reported in the striatum of patients with Parkinson's disease. The reduction in the activity of complex I is found in the substantia nigra, but not in other areas of the brain, such as globus pallidus or cerebral cortex. Therefore, the specificity of mitochondrial impairment may play a role in the degeneration of nigrostriatal dopaminergic neurons. This view is supported by the fact that MPTP generating 1-methyl-4-phenylpyridine (MPP(+)) destroys dopaminergic neurons in the substantia nigra. Although the serum levels of CoQ10 is normal in patients with Parkinson's disease, CoQ10 is able to attenuate the MPTP-induced loss of striatal dopaminergic neurons.

Aging↗

Solitary nodular goiter. Review of cytomorphologic features in 441 cases.

OBJECTIVE: To study the cytomorphologic features of solitary nodular goiters (SNG). STUDY DESIGN: May-Grünwald-Giemsa-stained smears in 441 SNG diagnosed by ultrasonography and fine needle aspiration (FNA) and found to have optimum cellular material at review were subjected to detailed cytologic assessment. The age of the patients ranged from 11 to 75 years, with a median of 35. Male: female ratio was 69:372. The parameters for cytologic assessment included cellularity, colloid content, acinar formation, papillary formation, intranuclear cytoplasmic inclusions, nuclear grooves, marginal vacuoles, Hürthle cells and various inflammatory cells. Histopathology reports on thyroidectomy specimens were available in 27 cases from two Delhi hospitals. RESULTS: Hyperplastic nodules (68 cases) differed significantly from colloid goiters (269 cases) by having more cases with excessive cellularity, acinar formation and marginal vacuoles (P < .001). There was also a significant difference with respect to papillary formation and moderate-to-excessive colloid content (P < .001). As compared to hyperplastic nodules, neoplasms (60 cases) had a significantly higher number of cases with papillary formation, intranuclear inclusions and nuclear grooves but lower number of cases with marginal vacuoles (P < .01-.001). Among neoplasms, usual papillary carcinoma (19 cases) differed from follicular neoplasms (20 cases) with respect to acinar formation, papillary formation and nuclear grooves (P < .001). A significant difference was also observed with respect to colloid content and nuclear inclusions. Follicular variant of papillary carcinomas (FVPC) (10 cases) emerged as a distinct cytologic entity following review and differed from usual papillary carcinomas in having a higher number of cases with acinar formation, tubular formation and marginal vacuoles (P < .01-.001) and lower number of cases with nuclear grooves (P = .05). FVPC also differed from follicular neoplasms with respect to papillary formation, tubular formation, intranuclear inclusions and nuclear grooves (P < .01-.001). Overall cytohistologic agreement was achieved in 24 of 27 (88.9%) cases. CONCLUSION: Detailed cytologic assessment of FNA smears-in SNG was helpful in highlighting parameters that differentiate between various types of goiters.

Adolescent↗

Cytomorphology of adrenocortical carcinoma and comparison with renal cell carcinoma.

OBJECTIVE: To review the cytomorphologic features of adrenocortical carcinoma (ACC), correlate them with histology and compare them with the cytomorphologic features of very similar renal cell carcinoma (RCC) on fine needle aspiration (FNA) smears. STUDY DESIGN: Cytomorphologic features in 7 cases of ACC in FNA smears were analyzed and compared with those in 10 cases of RCC. Five cases of ACC and five of RCC were later confirmed on histopathology. Parameters analyzed pertained mainly to architectural, cytoplasmic and nuclear features. RESULTS: The presence of cells in sheets with a central, thin-walled vascular core (endocrine vascular pattern); monomorphic cell population; eccentric nuclei; focal dramatic anisonucleosis; and focal spindling with crushing was a prominent feature of ACC in contrast to RCC, which showed mainly an acinar pattern with only a focal endocrine pattern, well-defined cytoplasmic angles and projections, and cytoplasmic vacuolations; pleomorphism, if present, was gradual and seen uniformly in all the cells. Univariate analysis using the chi 2 test showed the presence of endocrine architecture; focal dramatic anisonucleosis; crushed spindle fragments; eccentric nuclei; and absence of cytoplasmic vacuolizations as significant differentiating features in favor of ACC (P < .05). CONCLUSION: A cytomorphologic comparison of ACC with RCC showed that differentiation is possible by a set of statistically significant features that not only have diagnostic value but, as with crushed spindle fragments, also have prognostic significance.

Adrenal Cortex Neoplasms↗

Use of continuous quality improvement to identify barriers in the management of hypertension.

We have made great strides in understanding the pathophysiology and medical management of hypertension, yet barriers to effective blood pressure control remain. The process of identifying the barriers within the health care system may be as important as the barriers themselves. Our primary purpose was to apply the widely accepted tool, Continuous Quality Improvement (CQI), to identify barriers to the management of hypertension. We wanted to identify the most important factors and (or) persons in effective blood pressure control and to compare costs, satisfaction, and blood pressure control among subgroups of patients to identify those most likely to benefit from interventions. We recruited patients with essential hypertension who came to a university-based clinic staffed by family physicians and residents; 181 patients with hypertension were identified and asked at the time of their visit to complete a questionnaire relating to the management of their blood pressure. Twenty-five physicians and 8 medical assistants were also asked to complete a similar questionnaire regarding their perceptions of barriers to blood pressure management. All other information came from the patients' medical records. Blood pressure control was based on a reading taken on the date the questionnaire was completed. Student's t test was used to determine if statistically significant differences existed in blood pressure control, patient satisfaction, and total costs for certain subgroups; regression analysis was used to determine correlations. We had completed questionnaires from 91 patients, 89 physicians, and 79 staff. The physicians and staff were of course involved; however, we found that the patients' gestalt was extremely important in blood pressure control. Our patients perceived that lifestyle modifications such as exercise and weight loss were the greatest barrier to better blood pressure control. The cost of certain antihypertensive drugs was an obstacle for some patients. African Americans had poorer blood pressure control, and their satisfaction of care was significantly lower than that of other races. Our patients taught us that the 2 major barriers to blood pressure control were changes in lifestyle and reducing the cost of medications. We also found that our African American patients showed the poorest blood pressure control and the greatest dissatisfaction with their care. We surmise that the greatest benefit of any intervention would be expected in this population. We demonstrated that CQI can be used to identify barriers to hypertension management and subgroups of patients likely to benefit from interventions.

Adult↗

Tuberculosis of bones and joints of the foot: an analysis of 22 cases.

Skeletal tuberculosis constitutes 1% to 3% of extrapulmonary cases and involvement of foot bones is rare. Lack of awareness and a confusing clinical and radiological picture often lead to a delay in diagnosis. We reviewed 23 feet seen over a 3.5-year period. Most cases were children or young adults less than 40 years of age; isolated bony involvement was seen in 10 feet, with the calcaneus being involved in five cases. Articular involvement at presentation was seen in 13 cases and these cases had significantly higher delays in diagnosis. Twenty cases responded to antitubercular therapy alone while one case had to be operated (there was one fatal outcome). Complete resolution of sequestra was seen with antitubercular therapy alone. The results were better in cases with isolated bony involvement, while cases with joint involvement had residual sequelae in the form of stiffness or pain. Two patients were advised arthrodesis. Early diagnosis and antitubercular therapy is essential to prevent joint involvement from periarticular bony lesions; surgical intervention is rarely needed. A high index of suspicion has to be maintained in high risk groups like Asian immigrants. Concomitant extraskeletal lesions may not always be present.

Adolescent↗

Implant complications and failures: the single-tooth restoration.

The single-tooth implant restoration appears to be an ideal method of replacing missing natural teeth in a healthy dentition. Most follow-up studies report a high success rate. The restoration is seen by many clinicians as a relatively straightforward technique easily adapted to general dental practice and popular with patients, although it is not without complications. The purpose of this paper is to look at common problems following the placement of root-formed endosseous dental implants. A number of implant systems are reviewed and the results of the authors' clinical experiences reported.

Bite Force↗