Antioxidant and antimicrobial activities of Bauhinia racemosa L. stem bark

The present study was carried out to evaluate the antioxidant and antimicrobial activities of a methanol extract of Bauhinia racemosa (MEBR) (Caesalpiniaceae) stem bark in various systems. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the methanol extract increased in a concentration-dependent manner. About 50, 100, 250, and 500 æg MEBR inhibited the peroxidation of a linoleic acid emulsion by 62.43, 67.21, 71.04, and 76.83 percent, respectively. Similarly, the effect of MEBR on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays the IC50 value of the extract was 152.29 æg/ml. MEBR inhibited the nitric oxide radicals generated from sodium nitroprusside with an IC50 of 78.34 æg/ml, as opposed to 20.4 æg/ml for curcumin. Moreover, MEBR scavenged the superoxide generated by the PMS/NADH-NBT system. MEBR also inhibited the hydroxyl radical generated by Fenton's reaction, with an IC50 value of more than 1000 æg/ml, as compared to 5 æg/ml for catechin. The amounts of total phenolic compounds were also determined and 64.7 æg pyrocatechol phenol equivalents were detected in MEBR (1 mg). The antimicrobial activities of MEBR were determined by disc diffusion with five Gram-positive, four Gram-negative and four fungal species. MEBR showed broad-spectrum antimicrobial activity against all tested microorganisms. The results obtained in the present study indicate that MEBR can be a potential source of natural antioxidant and antimicrobial agents.

Reversible segmental portal hypertension--an unusual presentation of abdominal tuberculosis in a renal transplant recipient.

Infections are the commonest cause of morbidity and mortality in renal transplant recipients. In India, tuberculosis is a one such common infection in these patients and presents with protean manifestations. We report here a case of pyrexia of unknown origin (PUO) and segmental portal hypertension in a renal transplant recipient. Search for the cause of portal hypertension revealed abdominal tubercular lymphadenitis. Treatment with anti-tubercular therapy caused regression of segmental portal hypertension.

Lipid peroxidation and diabetic retinopathy.

The high level of glucose in blood for a long duration is the main cause of the development of retinopathy. So yearly screening of patients newly diagnosed with NIDDM diabetes is recommended because rare cases of treatable diabetic retinopathy have occurred early in one course of NIDDM diabetes. Hyperglycaemia leads to non-enzymatic glycosylation of proteins and HbA1C was found increased. Antioxidants such as GSH and SOD level is found decreased in retinopathy conditions due to the higher lipid peroxidation, which is evident from high MDA and DC values. So it can be clearly stated that increase in the free radical by hyperglycaemia, lipid peroxidation and advanced glycosylation endproducts along with decreased antioxidants are the causative agents for the development of retinopathy.

Studies on proteases and alpha-macroglobulin activity in amphibian blood plasma.

Frog plasma effectively hydrolysed the synthetic chromogenic substrates, H-D-Glu-Gly-Arg-p-nitroanilide (S-2444), benzoyl-Ile-Glu-Gly-Arg-p-nitroanilide (S-2222) and acetyl-Ile-Glu-Gly-Arg- p-nitroanilide (S-2423), all sensitive substrates for trypsin. Moderate hydrolytic activities was observed with H-D-Phe-Pip-Arg-p-nitroanilide (S-2238, substrate for thrombin) and H-D-Pro-Phe-Arg-p-nitroanilide (S-2302, substrate for plasma kallikrein). Frog plasma contained moderate alpha-macroglobulin activity. When plasma was incubated at 37 degrees C, the macroglobulin activity decreased in a time dependent manner while only a moderate decrease in the protease activity was observed. Ten fold dilution of plasma with 0.1 M phosphate buffer, pH 7.6 prevented the inherent loss of macroglobulin activity but it had no effect on protease activity. Dye ligand chromatography of the plasma on red Sepharose revealed that bulk of alpha-macroglobulin activity along with minor proteolytic activity (S-2222 hydrolysis) was present i the washings. On the other hand, about one third of the alpha-macroglobulin activity and bulk of the protease activity was bound to the column and were eluted with 1.5 M NaCl. alpha-Macroglobulin activity in red Sepharose washings and elutions on chromatography on Sephadex G-200, was eluted in two regions with Ve/Vo value of 1.33 and 1.08, respectively.

Bidirectional Glenn shunt: a step in the right direction.

Bidirectional Glenn (BDG) shunt was carried out in 14 patients (age range 1.5-22 years; mean 9.3 years) for a variety of congenital cyanotic heart diseases with decreased pulmonary blood flow. Postoperative cardiac catheterisation was carried out in 10 patients including successful balloon angioplasty of the shunt and LPA in one patient. There was a significant improvement in oxygen saturation and a drop in haematocrit level at follow-up. Doppler echocardiography studies in 13 patients revealed functioning shunts in all cases with low velocity continuous flow. Thus BDG is a useful palliative procedure and could be undertaken as the first stage of total cavopulmonary connection in high-risk Fontan groups where biventricular repair is not feasible.