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V Lakshmi

Publications and source records attributed to V Lakshmi.

84 records · Page 5Linked to original sources
PubMed1985

Evidence for independent 11-oxidase and 11-reductase activities of 11 beta-hydroxysteroid dehydrogenase: enzyme latency, phase transitions, and lipid requirements.

Experimental modification of the membrane structure of rat liver microsomes affected the behavior of the 11-oxidase and 11-reductase components of 11 beta-hydroxysteroid dehydrogenase in different ways. 1) The latency of 11-oxidase was released by detergents, phospholipases, or elevated temperature; 11-reductase activity was not increased by these manipulations. 2) 11-Reductase was rapidly inactivated at 25 C and 37 C; 11-oxidase was stable at these temperatures. 3) Arrhenius plots of microsome bound 11-reductase between 5 C and 40 C showed discontinuity at 23 C. Activation energies above and below the critical temperature were 2 kcal and 16 kcal, respectively. Solubilized 11-reductase showed no discontinuity [activation energy (Ea) = 15 kcal]. Ea for 11-oxidase was 15 kcal at all temperatures for membrane bound or solubilized enzyme, with no discontinuities. 4) Phospholipases A2 and C rapidly inactivated 11-reductase. Triton DF-18 regenerated 50% of the reductase activity of phospholipase C-treated microsomes, but had no effect on phospholipase A2-treated microsomes. Phospholipases increased 11-oxidase activity. The independent behavior of corticosteroid 11-oxidase and 11-reductase are consistent with the properties of closely associated, independent enzymes.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1985

A clinical study of benzydamine for the treatment of radiotherapy-induced mucositis of the oropharynx.

A double-blind, randomized clinical study was undertaken to determine the analgesic and antiinflammatory effectiveness of benzydamine in patients with radiation-induced mucositis of the oropharynx. Of the 67 patients in the study, 37 patients were on benzydamine and 30 patients on a placebo. The results of the study showed that benzydamine possessed a significant analgesic activity as evidenced by relief of mouth and throat pain induced by radiation therapy. It is also noted that the patients on benzydamine exhibited a cumulative relief of oral pharyngeal pain and discomfort over the time of treatment, as compared to those on the placebo. These effects of benzydamine in the present study might be a result of the antiinflammatory property of the drug. The cumulative and prolonged effectiveness of benzydamine makes it of distinct value compared with the commonly available local anaesthetics such as lidocaine. Benzydamine appears to provide a useful addition to the therapeutic armamentarium for alleviating the symptoms of oral pharyngeal mucositis.

Adult↗
PubMedDate not supplied

Serodiagnosis of subacute sclerosing panencephalitis by enzyme linked immunosorbent assay.

Thirty three young patients (23 males and 10 females), between 3-20 years of age, with a clinical suspicion of subacute sclerosing panencephalitis (SSPE) were evaluated over a period of 4 years. A past history of measles was obtained in 42.4% of the cases. One child was immunised against measles. Measles specific antibodies (IgG) were demonstrated in the cerebrospinal fluid (CSF) from 30 (90.9%) of the 33 patients by ELISA. In the remaining three cases the antibodies were detected only in the serum. Serodiagnosis of SSPE by ELISA had a sensitivity of 100%, a specificity of 93.3% and a positive predictive value of 100%.

Adolescent↗
PubMedDate not supplied

Corticosteroid 11 beta-hydroxysteroid dehydrogenase activities in vertebrate liver.

In this paper, we examine corticosteroid 11 beta-oxidation and 11-reduction as properties of the microsomal 11 beta-hydroxysteroid dehydrogenase complex in vertebrate livers. No hepatic activity in the oxidative direction (11 beta -dehydrogenase) was found in the frog, toad, mud puppy, shark, and bird livers. In contrast, all mammalian livers had active oxidizing enzymes. Latency, defined as microsome-linked activity released by the detergent Triton DF-18, was a property of 11 beta-dehydrogenase in all mammalian livers. Mammal, bird, and dogfish livers reduced 11-dehydrocorticosteroids (11-reductase), while amphibians and bony fish did not. With the exception of rat liver, latency was a property of all the mammalian liver 11-reductases examined.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMedDate not supplied

Marine natural products: pyrrololactams from several sponges.

Two pyrrololactams, likely degradation products of more complex known guanidines, were isolated from several marine sponges. 5-Bromo- and 4,5-dibromopyrrole-1-carboxylic acid methyl esters were also isolated. A complex guanidine metabolite, poorly soluble in DMSO, was found to give sharp, reproducible nmr spectra in acid media.

Animals↗
PubMedDate not supplied

Western blot profile in HIV infection.

BACKGROUND: Although the overall sensitivity and specificity of the western blot (WB) test for detection of antibodies to various viral proteins is high, there has been a substantial difference in the timing of the appearance of antibody bands and their intensities during different stages of HIV infection. AIMS: Mapping different band patterns of Western blot results and correlating them with stages of HIV infection. METHODS: We performed a retrospective study with 1,467 HIV-1 infected cases confirmed by WB test between January 2002 to July 2005, with the objective of mapping different band patterns of western blot results and determining whether the presence or absence of certain bands was associated with any specific stage of HIV infection. For the interpretation of the WB results in this study, the guidelines recommended by NACO, India were followed. RESULTS: Reactivity with all the bands was the most commonly observed WB pattern, occurring in 92.91% (1363/1467) of cases, whereas the other 7.09% showed uncommon band patterns. Of all individual bands, p31 band was the most frequently missing one, absent in 7.09% cases. On classifying the WB reactive cases by the WHO clinical staging system, 38.45% (564/1467) were in Stage 1, 47.99% (704/1467) in stages 2 and 3 and 13.56% in stage 4. Correlation of CD4 cell counts with the various uncommon band patterns showed that only 5.56% (4/72) had counts in the 200-500 cells/microl range, whereas 45.83% and 48.61% had counts of < 200 and> 500 cells/microl respectively. CONCLUSION: Interpretation of the WB band pattern in combination with clinical features may be occasionally useful in predicting the stage of HIV infection.

Antigen-Antibody Reactions↗
PubMedDate not supplied

Routine screening for HIV and hepatitis B in patients undergoing cardiac catheterisation: the need to make it mandatory.

Reuse of catheters during cardiac catheterisation and interventions is a routine practice in our country. However, the reuse of catheters is complicated by the inherent difficulties in adequate sterilisation of these devices. Gas sterilisation with ethylene oxide has been found to be ineffective when residual fluid was present. Recent reports indicate an increased prevalence of blood-borne viral infections especially Hepatitis B virus and Human Immunodeficiency virus in India. We analysed the data of patients from our Institute over the past seven years (1992-1998) who underwent routine screening for Human Immunodeficiency virus and Hepatitis B virus prior to cardiac catheterisation. During this period, the prevalence of Hepatitis B virus increased by 1.5 times and that of Human Immunodeficiency virus by 2.5 fold. In this changed scenario, it is advisable to perform a mandatory screening of all the patients undergoing invasive cardiac procedures so as to minimise the risk of transmission from one patient to another and also to the catheterisation laboratory personnel. In the patients with a positive result, proper precautions can be taken and the entire material used for cardiac catheterisation can be discarded.

Cardiac Catheterization↗