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Biomedical subjects

S Subramanian

Publications and source records attributed to S Subramanian.

At least 145 records · Page 8Linked to original sources
PubMed1995

Endothelin receptor mRNA expression in renal medulla identified by in situ RT-PCR.

Three subtypes of endothelin (ET) receptors have been identified by cDNA cloning, namely ET-RA, ET-RB, and ET-RC. In the current study the precise cellular distribution of the ET receptor subtypes in the renal medulla was explored by detecting the corresponding polymerase chain reaction (PCR)-amplified cDNAs by in situ reverse transcription (RT)-PCR. The PCR-amplified cDNAs were detected either by direct incorporation using digoxigenin-dUTP (dig-dUTP) as a nucleotide substrate in the PCR reaction or by in situ hybridization with the dig-dUTP-labeled probe. ET-RB mRNA was detected exclusively in the epithelial cells of the inner and outer medullary collecting duct. In contrast, ET-RA message was observed primarily in interstitial cells and pericytes of the vasae rectae in the outer and inner medulla. Southern blot analysis of PCR-amplified cDNAs reverse transcribed from extracted RNA of rat renal medulla confirmed the specificity of the RT-PCR products. ET-RC mRNA was not detected. We conclude that ET-RB is the major ET receptor found in rat renal medulla and is expressed exclusively on inner medullary collecting duct cells. The pattern of ET receptor mRNA expression described suggests different physiological actions for ET on the diverse cellular structures of the renal medulla.

Animals↗
PubMed1994

Status of antioxidant systems in human carcinoma of uterine cervix.

Lipid peroxides, glutathione content and the activities of antioxidant enzymes were estimated in patients who had carcinoma of the uterine cervix, and the values were compared with those of normal. The results showed a remarkable reduction in glutathione content and in the activities of catalase and superoxide dismutase in neoplastic tissue in stages II, III and IV (P < 0.001) whereas the activities of glutathione peroxidase and glutathione reductase were significantly lower in stage III and IV patients than that of normal controls. The tissue level of lipid peroxides and the activity of glutathione-S-transferase were found to be significantly higher than that of normals from stage II onwards. These observations suggested the impaired antioxidant status in carcinoma of the uterine cervix.

Adenocarcinoma↗
PubMed1994

Determination of cobalt in biological samples by radiochemical neutron activation analysis employing reverse-phase chromatography.

We report the final part of our "on-line yield" pilot program in this article. This last part deals with aspects of accuracy and precision of the determination of cobalt in biological materials by RNAA with on-line yield determination. To obtain an insight into the accuracy of the technique, certified reference materials were analyzed, and for selected materials, results obtained by INAA and RNAA of identical samples have been compared. It shows that the mineralization in our RNAA scheme may be a sample-related source of systematic errors that is not related to the presence or absence of HF. Finally, we present some critical notes on pros and cons of the practice of on-line yield concept and some ideas for further research.

Animals↗
PubMed1994

Biochemical evaluation of the antiulcerogenic effect of Cauvery-100 (an ayurvedic formulation) in rats.

Due to the varied pathogenesis of ulcers, a number of pharmacologically different antiulcer drugs are now used in the treatment of the condition. The suitability of certain of these drugs is still to be established. Cauvery-100 is an ayurvedic formulation consisting of plant ingredients, and has been suggested to be useful in the treatment of gastrointestinal disorders. In the present study this drug was tested for its antiulcerogenic effect. The number of lesions on gastric mucosa decreased markedly after 15 days oral treatment with Cauvery-100 in rats with indomethacin-induced ulcers. The volume and total acidity of the gastric juice also decreased in the treated rats. The hexose, hexosamine and sialic acid levels of gastric contents, which were increased in untreated rats returned to near normal levels after 15 days of treatment. Protein in the gastric juice was elevated in untreated rats but returned to near normal levels after 15 days of treatment. Cauvery-100 acts both to decrease the acidity and to increase the mucosal defence in the gastric areas, thereby justifying its use as an antiulcerogenic agent.

Animals↗
PubMed1994

Pressure dynamics of various irrigation techniques commonly used in the emergency department.

STUDY OBJECTIVE: To evaluate the pressure dynamics of common irrigation techniques used in the treatment of traumatic wounds. DESIGN: Matched experimental trial. PARTICIPANTS: Ten male volunteers. INTERVENTIONS: Pressure curves were obtained while performing manual irrigation with 250-mL boluses of normal saline with 19-gauge needles on 35-mL syringes, 19-gauge needles on 65-mL syringes, IV bags pierced with 19-gauge needles, and plastic bottles pierced with 19-gauge needles. Measurements also were obtained using an IV bag with tubing attached to either a 19-gauge or 16-gauge needle within a pressure cuff inflated to 400 mm Hg. RESULTS: Median peak pressures were 35 lb/in.2 (psi)(range, 25 to 40 psi) and 27.5 psi (range, 15 to 40 psi) using a 35-mL syringe and a 65-mL syringe, respectively. Median peak pressures with the IV bag and plastic bottle were 4 psi (range, 2 to 5.5 psi) and 2.3 psi (range, 1.2 to 4.5 psi), respectively. The IV bag in a pressure cuff generated pressures of 6 to 10 psi and 4 to 6 psi using 19-gauge and 16-gauge needles, respectively. CONCLUSION: Both 35-mL and 65-mL syringes with a 19-gauge needle are effective in performing high-pressure irrigation in the range of 25 to 35 psi. The use of IV bags and plastic bottles should be discouraged when high-pressure irrigation is required.

Adult↗
PubMed1994

Preimplantation single cell analyses of dystrophin gene deletions using whole genome amplification.

Primer extension preamplification (PEP) increases the scope and capacity of single cell genetic diagnosis by generating sufficient template to perform multiple subsequent DNA analyses using the polymerase chain reaction. We report the simultaneous analysis of single cells at five commonly deleted dystrophin exons and at the ZFX/ZFY loci. Ninety three percent of PEP reactions with single amniocytes, chorionic villus cells and blastomeres were successful, and a blinded analysis of single lymphoblasts from affected males resulted in 93% diagnostic accuracy, demonstrating its applicability in preimplantation prevention of Duchenne muscular dystrophy. Transfer of unaffected male embryos and improved diagnostic reliability are achieved with the ability to perform replicate multilocus analyses from the same blastomere.

Base Sequence↗
PubMed1994

Relative potency of DEPA as a repellent against the sandfly Phlebotomus papatasi.

The insect repellent N,N-diethylphenylacetamide (DEPA) was compared with two commercial repellents, N,N-diethyl-m-toluamide (DEET) and dimethyl phthalate (DMP), for protection against 3-day-old unfed females of the sandfly Phlebotomus papatasi (Scopoli) under laboratory conditions, using host rabbits. Both DEPA and DEET were found to be more effective than DMP, but there was no significant difference between the efficacy of DEPA and DEET.

Acetamides↗
PubMed1994

Rates of acquisition and loss of Wuchereria bancrofti infection in Culex quinquefasciatus.

Rates of acquisition and loss of parasitic infection in the vector host of Wuchereria bancrofti were estimated using a new method. The age of parasitic infections was estimated from the abdominal condition, determined on the basis of Sella's stages of blood digestion and ovary development, and parity of the vector host and larval stages of the parasite. A negative exponential relationship between age and number of W. bancrofti infections provided estimated daily losses of 25.3% and 33.2% of the initial infection from the resting and biting populations, respectively, of the mosquito Culex quinquefasciatus. The rates per day of acquisition of infection estimated from resting and biting female Cx. quinquefasciatus were found to be 9.6% and 8.6%, respectively. The mean minimum developmental time for W. bancrofti infective larvae estimated from the natural resting and biting populations were 8.9 +/- 1.41 (+/- SEM) and 8.33 +/- 0.85 days, respectively, which was somewhat less than the duration observed under laboratory conditions. Comparisons of the estimates (mean age, rates of acquisition, and loss of infections) based on the resting and biting data suggest that the rates are independent of the method of collecting mosquitoes.

Animals↗
PubMed1994

Mycoplasma hominis in pelvic inflammatory disease.

Fifty one cases of Pelvic Inflammatory disease (PID) and sixty one control subjects were screened for the genital mycoplasmas. Cervical swabs, urine & blood were collected from the patients and the control subjects and were processed by standard techniques for isolation and identification of bacteria, fungi and mycoplasmas. The rate of isolation of M. hominis from the PID and controls were 54.90% and 16.39% respectively, and this difference was statistically significant (p. < 0.001). Metabolic inhibition test revealed a titer of > 1:2 in 92% of the acute sera of PID against the homologous strain and there was a rise or fall in four fold titer in 45% of the convalescent sera tested for.

Antibodies, Bacterial↗
PubMed1994

Diagnostic and prognostic role of plasma and urinary sialic acid in human carcinoma of uterine cervix.

In different stages of carcinoma of uterine cervix, the plasma total sialic acid (TSA), lipid bound sialic acid (LSA) and urinary sialic acid levels were studied before and after radiation treatment. Glycocomponents of glycoproteins were found to be increased progressively as the disease advances. The increased levels of glycocomponents were found to be decreased to near normal levels after radiotherapy. This may be a better indicator of the disease in conjunction with the studies of cervical smear rather than the latter alone.

Adult↗
PubMed1993

MRI and MRS studies on the time course of rat brain lesions and the effect of drug treatment: volume quantification and characterization of tissue heterogeneity by parameter selection.

Magnetic resonance imaging has been used to follow the time course of lesions induced in the rat brain as an animal model for characterization of the volume of the lesion. The dispersion in spin-spin relaxation has been used to characterize the nature of the brain lesion. Parameter selective estimation of T2, quantitative determination of the lesion size and volume selective in vivo proton spectroscopy have been employed for the purpose. The work has been carried out on rats which were subject to lesioning by ibotenic acid as a model for excitotoxicity and also on rats which received doses of ibotenic acid and subsequent doses of the NMDA antagonist drug MK 801 (dizocilpine). The time course of the progress of the lesions in untreated animals and the effect of neuroprotection by MK 801 was continuously monitored in all test animals. Further, a relatively new inhalation anesthetic agent, isoflurane, has been employed. A more logical and semiquantitative T2 bandwidth demarkation useful in distinguishing different degrees of lesioning from the onset and up to the 'edema' stage through penumbra (mild lesion), medium degree lesion and severe lesion has been proposed.

Animals↗
PubMed1993

Atrioventricular canal defect: two-patch repair and tricuspidization of the mitral valve.

Between November 1978 and May 1991, a two-patch repair with tricuspidization of the left atrioventricular valve was performed in 104 patients with complete atrioventricular canal defect. Mean age was 12 months for the 68 patients who underwent primary repair and 22 months for the 36 patients who had previous pulmonary artery banding. Eleven patients died within 30 days of operation and 4 died late. Reoperation was carried out in 2 patients. Eighty-six patients were in sinus rhythm after operation. One patient required a permanent pacemaker for complete heart block. Follow-up data for 1 to 13 years are available in 80 of 89 survivors (90%). Actuarial survival at 13 years is 81% and event-free survival is 92%. Seventy-six patients are in New York Heart Association class I and 4 in class II. Postoperative echocardiogram of these patients showed minimal or no mitral regurgitation. The advantages of this technique are preservation of valve integrity, durable mitral valve repair, and rare reoperation or heart block even in younger patients.

Child, Preschool↗
PubMed1993

Antiviral properties of the seed extract of an Indian medicinal plant, Pongamia pinnata, Linn., against herpes simplex viruses: in-vitro studies on Vero cells.

Pongamia pinnata, Linn., an Indian medicinal plant used in the Ayurvedha and Siddha traditional medicine systems, for treatment of clinical lesions of skin and genitalia, was evaluated for antiviral properties against herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) by in-vitro studies in Vero cells. A crude aqueous seed extract of P. pinnata completely inhibited the growth of HSV-1 and HSV-2 at concentrations of 1 and 20 mg/ml (w/v), respectively, as shown by complete absence of cytopathic effect.

Animals↗