PubMed Health⌕ Search

Biomedical subjects

R V Shah

Publications and source records attributed to R V Shah.

At least 19 recordsLinked to original sources

Intradiskal electrothermal therapy: a preliminary histologic study.

OBJECTIVE: To characterize descriptively the histologic and temperature effects of intradiskal electrothermal annuloplasty on human cadaveric lumbar disks. DESIGN: In vitro histologic study. SETTING: Hospital-based soft-tissue research laboratory. CADAVERS: Six human cadaveric lumbar disks, from 5 cadavers aged 39 to 79 who died from nonspine-related causes. INTERVENTIONS: Intradiskal electrothermal therapy (IDET) by using a standard high-temperature heating protocol with the temperature of the probe gradually increased from 65 degrees C to 90 degrees C over 16.5 minutes. Disks were stained and examined by light microscopy and electron microscopy. MAIN OUTCOME MEASURES: Temperatures in outer annulus, gross macroscopic changes, and histologic damage. RESULTS: Gross inspection showed a small circumferential area of tissue alteration localized to the posterior annulus but not extending to the endplates. Light microscopy of the posterior aspect of the lumbar disks showed denaturation, shrinkage, and coalescence of annular collagen; the anterior portions, which served as internal controls, showed no evidence of damage. The endplates were structurally preserved and showed no evidence of damage. Electron microscopy showed extensive collagen disorganization, decreased quantity of collagen, collagen fibril shrinkage, and chondrocyte damage when compared with a control portion. The temperature curves showed parallel changes in temperature at the level of the probe and at the posterior portion of the disk. CONCLUSIONS: IDET raises temperatures sufficiently to induce collagen denaturation and coalescence. These histologic changes may play a substantial role in the clinical efficacy of IDET.

Adult↗

Valve replacement in patients with endocarditis and acute neurologic deficit.

BACKGROUND: Acute neurologic deficits occur in up to 40% of patients with left heart endocarditis. Appropriate evaluation and management of patients with acute neurologic dysfunction who require valve operations for endocarditis remain controversial. This retrospective review was undertaken to develop recommendations for the evaluation and treatment of these challenging patients. METHODS: From 1983 to 1995, 247 patients underwent operations for left heart native valve endocarditis at the Johns Hopkins Hospital. From a review of medical and pathology records, 34 patients (14%) with preoperative neurologic deficits were identified. Data on these 34 patients were recorded and analyzed. RESULTS: Causes of neurologic dysfunction included embolic cerebrovascular accident (n = 23, 68%), embolic cerebrovascular accident with hemorrhage (n = 4, 12%), ruptured mycotic aneurysm (n = 3, 9%), transient ischemic attack (n = 2, 6%), and meningitis (n = 2, 6%). Preoperative diagnostic studies included computed tomography (32 patients), magnetic resonance imaging (11 patients), cerebral angiogram (14 patients), and lumbar puncture (2 patients). Computed tomography demonstrated structural lesions in 29 of 32 patients; in only 1 patient did magnetic resonance imaging reveal a lesion not already seen on computed tomography. Of 14 patients having cerebral angiograms, 7 had a mycotic aneurysm. Three mycotic aneurysms had ruptured, and these were clipped before cardiac operations. The mean interval from onset of neurologic deficit to cardiac operation was 22.2 +/- 2.8 days for all patients and 22.1 +/- 3.0 days for those with embolic cerebrovascular accident. The hospital mortality rate was 6%. New or worse neurologic deficits occurred in 2 patients (6%). CONCLUSIONS: Neurologic deficits are common in patients with endocarditis referred for cardiac operations. Despite substantial preoperative morbidity, most of these patients do well if the operation can be delayed for 2 to 3 weeks. Computed tomography scan is the preoperative imaging technique of choice, as routine magnetic resonance imaging and cerebral angiogram are unrewarding. Cerebral angiogram is indicated only if computed tomography reveals hemorrhage.

Acute Disease↗

A case-management system for coronary risk factor modification after acute myocardial infarction.

OBJECTIVE: To evaluate the efficacy of a physician-directed, nurse-managed, home-based case-management system for coronary risk factor modification. DESIGN: Randomized clinical trial in which patients received a special intervention (n = 293) or usual medical care (n = 292) during the first year after acute myocardial infarction. SETTING: 5 Kaiser Permanente Medical Centers in the San Francisco Bay area. PATIENTS: 585 men and women aged 70 years or younger who were hospitalized for acute myocardial infarction. INTERVENTION: In the hospital, specially trained nurses initiated interventions for smoking cessation, exercise training, and diet-drug therapy for hyperlipidemia. Intervention after discharge was implemented primarily by telephone and mail contact with patients in their homes. All medically eligible patients received exercise training; all smokers received the smoking cessation intervention; and all patients received dietary counseling and, if needed, lipid-lowering drug therapy. OUTCOME: Smoking prevalence and plasma low-density lipoprotein cholesterol (LDL) concentrations were measured 2 months after infarction, and functional capacity was measured 6 months after infarction. RESULTS: In the special intervention and usual care groups, the cotinine-confirmed smoking cessation rates were 70% and 53% (P = 0.03), plasma LDL cholesterol levels were 2.77 +/- 0.69 mmol/L and 3.41 +/- 0.90 mmol/L (107 +/- 30 mg/dL and 132 +/- 30 mg/dL) (P = 0.001), and functional capacities were 9.3 +/- 2.4 METS and 8.4 +/- 2.5 METS (P = 0.001), respectively. CONCLUSION: In a large health maintenance organization, a case-management system was considerably more effective than usual medical care for modification of coronary risk factors after myocardial infarction.

Adult↗

Response with combined modality treatment in childhood rhabdomyosarcoma.

Children diagnosed with rhabdomyosarcoma at the Tata Memorial Hospital during the period January 1986-December 1988 were studied. All were treated with combination chemotherapy incorporating vincristine, Adriamycin, and cyclophosphamide given sequentially in repeated cycles over 18 months, along with local radiotherapy. Of 24 patients, 18 patients had advanced-stage disease at onset. All patients have been followed up for 18 months or more. Of the 11 patients with group III disease, six are in complete remission; of the six patients with group IV disease, two patients are in complete remission. These results are clearly better than those achieved in the past, where surgery was employed as the primary modality of therapy with chemoradiotherapy given only for patients with group IV disease.

Adolescent↗

Hairy cell leukaemia. A review of nine cases.

Nine consecutive patients with HCL seen over a period of five years were reviewed. Male: Female ratio was 8:1. Median age at diagnosis was 49 years. Weakness and fatigue (66%) were the commonest presenting symptoms and splenomegaly (66%) was the commonest physical findings. Varying degrees of pancytopenia was the consistent feature in majority of cases. Diagnosis was made on the basis of bone marrow biopsy and characteristic EM picture. Forty-four percent of cases developed serious infection during their clinical course. Gram negative bacilli and fungi were the most frequently isolated organisms. Major sites of infections were pneumonia and septicemia. Splenectomy was carried out in four cases. Rapid recovery of haematological parameters without any significant complication was observed in all these cases. Two patients were treated with alfa-interferon. In both the cases recovery of haematological parameters was slow compared to those under going splenectomy. One patient treated with alfa-interferon died due to infection related complications while the other went into remission.

Adult↗

Changes in the visceral fat bodies associated with haematopoiesis and lipid metabolism, in relation to tail regeneration in the scincid lizard, Mabuya carinata: a histomorphological analysis.

In order to understand the role of visceral fat bodies in regeneration, a histomorphological analysis of the fat bodies in Mabuya during its tail regeneration was undertaken. The investigation revealed 2 interesting aspects; a visible shrinkage of the fat bodies and a fall in the histosomatic index (HSI), as well as an enhancement in haemopoietic activity and infiltration of lymphocytes in the fat bodies during the 1st 7 days of tail regeneration. These observations are taken to indicate the involvement of visceral fat bodies in the regenerative mechanics. The appearance of lymphocytes on the 5th and 7th days and their subsequent disappearance together with lipid depletion are construed from the functioning of lymphocytes in lipid transport during their passage to the wound site.

Animals↗

Alterations in liver dehydrogenases during tail regeneration in the gekkonid lizard, Hemidactylus flaviviridis.

Histochemical studies on the activities of alpha-GPDH, LDH, SDH and MDH in liver have been carried out during the different phases of tail regeneration in the lizard, Hemidactylus flaviviridis. Changes in the metabolic activities of the liver during regeneration indicate that during the initial phases of regeneration (namely, wound healing and blastema formation) the energetics of the hepatic tissue are anaerobically oriented, but later (i.e. during the growth phase) the TCA cycle appears to be predominant.

Animals↗

Possible role of beta-glucuronidase in the normal and regenerating tail of the house lizard, Hemidactylus flaviviridis.

Histochemical demonstration of beta-glucuronidase was carried out in the normal and regenerating tail of the house lizard, Hemidactylus flaviviridis. Greater enzyme activity was particularly discernible in the stratum germinativum of the skin of the normal and fully regenerated tail. During regeneration most of the cellular elements of the blastema and the differentiating regenerate exhibited enzyme activity. Distribution of the enzyme beta-glucuronidase is correlated with the high degree of cellular proliferation. The role of the enzyme in the catabolism of mucopolysaccharides is also implicated during the wound-healing phase. In the full-grown regenerate the intensity and distribution of the enzyme activity were found to be the same as those observed in the normal tail.

Animals↗