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R Parthasarathy

Publications and source records attributed to R Parthasarathy.

107 records · Page 6Linked to original sources
PubMed1976

Studies of immediate adverse reactions to different doses of a slow-release preparation of isoniazid.

'Double-blind' studies were carried out to assess the incidence of immediate adverse reactions to different doses of a slow-release preparation of isoniazid (matrix isoniazid). Individual doses of 30 mg/kg matrix isoniazid were well-tolerated but higher doses resulted in giddiness, the incidence being dose-related. The giddiness was characterized by a late onset and was usually present even at 24 hours. A few patients complained of gastro-intestinal symptoms. It is concluded that matrix isoniazid can be given to Madras patients in doses of 30-40 mg/kg without risk of an undue incidence of immediate adverse reactions.

Adult↗
PubMed1975

Synthesis and biological activity of 5-fluoro-4'-thiouridine and some related nucleosides.

The synthesis of a series of 4'-thio-5-halogenopyrimidine nucleosides, including the 5-fluoro, chloro, bromo and iodo derivatives, has been carried out by condensation of the 2,4-bis-O-trimethylsilyl derivatives of the corresponding pyrimidine bases with the protected 4-thio-D-ribofuranosyl chloride. Among these, the alpha and beta anomers of 4'-thio-5-fluorouridine inhibited the growth of leukemia L1210 cells at concentrations of 4 x 10(-7) and 2 x 10(-7) M, respectively, and that of S. faecium at 4 x 10(-9) and 6 x 10(-10) M, respectively. These compounds retained marked activity against strains of S. faecium resistant to 10(-3) M 5-fluorouracil or 5-fluorouridine. As determined in S. faecium cultures, 4'-thio-5-fluorouridine decreased the total protein content of the cells more markedly than it did their RNA or DNA content. X-Ray crystallography showed that substitution of sulfur for the oxygen in the carbohydrate ring markedly changes the conformation of that moiety.

Animals↗
PubMedDate not supplied

Delayed computed tomographic characterization of renal masses: preliminary experience.

BACKGROUND: To evaluate the performance of delayed contrast enhanced computed tomography (DCT) in characterizing renal masses. METHODS: Twenty-four patients with suspected renal masses or indeterminate renal masses on previous imaging studies were prospectively evaluated with preintravenous contrast imaging, conventional contrast-enhanced computed tomography (imaging initiated 2 min after intravenous contrast injection), and DCT (imaging initiated 13 min after injection of intravenous contrast). Only lesions larger than 1.0 cm were evaluated, with scanning parameters kept constant across the three scans. RESULTS: All pathologically confirmed renal cell carcinomas (n = 6) were detected on DCT using a threshold attenuation decrease of 10 Hounsfield units (HU). A significant decrease (p = 0.031) in attenuation occurred in renal cell carcinomas (mean = 29.6 +/- 23.6 HU) compared with the attenuation change (mean decrease = 1.1 +/- 7.1 HU), which occurred in non-neoplastic renal cysts (n = 34). Non-neoplastic renal cysts were correctly classified by DCT 32 of 34 times (94%). CONCLUSIONS: In this study, DCT distinguished renal cell carcinomas from non-neoplastic cysts in a vast majority of cases and may aid in characterizing incidentally discovered renal lesions on postcontrast CT.

Adenoma↗
PubMedDate not supplied

Lung transplantation without the use of antilymphocyte antibody preparations.

Survival, infection, and rejection rates and functional data are reported in 35 lung recipients treated with triple-drug immunosuppression without antilymphocytic antibody therapy. Early mortality (less than 60 days) was 6%. Thirty recipients (86%) are alive, with a mean follow-up period of 16 months (range, 1 to 36 months). Actuarial survival was 91% at 1 year and 83% at 2 years. Thirty-seven infections occurred in 24 patients. Actuarial freedom from infection was 61% at 3 months and 27% at 1 year. Only one patient died of infection (aspergillosis). Thirty-six episodes of acute rejection were treated in 23 patients. Time to first rejection was 14 +/- 7.8 days. Actuarial freedom from acute rejection was 36% at 2 months. Significant functional improvement was evident in all operative survivors. Pulmonary function and exercise performance data in patients without bronchiolitis obliterans remain stable 1 year after transplantation. We conclude that the use of triple-drug immunosuppression without antilymphocytic antibody preparations in lung transplantation provides effective immunosuppression with a low risk of serious infectious complications.

Actuarial Analysis↗