Photodermatoses in India.

Photodermatoses are a group of disorders resulting from abnormal cutaneous reactions to solar radiation. They include idiopathic photosensitive disorders, drug or chemical induced photosensitivity reactions, DNA repair-deficiency photodermatoses and photoaggravated dermatoses. The pathophysiology differs in these disorders but photoprotection is the most integral part of their management. Photoprotection includes wearing photoprotective clothing, applying broad spectrum sunscreens and avoiding photosensitizing drugs and chemicals.

Antiphospholipid syndrome in dermatology: An update.

Antiphospholipid syndrome (APS) is characterized by the presence of antiphospholipid antibodies, recurrent thrombosis, and fetal loss. Antiphospholipid antibodies are a family of autoantibodies that recognize various combinations of phospholipids, phospholipid-binding proteins, or both. APS can occur in the absence of underlying or associated disease (primary APS) or in combination with other diseases (secondary APS). The exact pathogenic mechanism by which these antibodies cause thrombosis is not known; however, several hypotheses, such as activation of platelet and endothelial cells and interference with the coagulation system, have been proposed. Diagnosis is based on the presence of at least one clinical and laboratory criterion each, according to International Consensus Statement on preliminary classification criteria. However, APS can be diagnosed in individuals even in the absence of some of the classification criteria. Clinical manifestations involve different organs and systems such as the blood vessels, central nervous system, skin, kidneys, gastrointestinal tract, heart, and placenta. The unifying mechanism of all these manifestations is thrombosis, either arterial or venous. Skin manifestations are varied and although not included in the diagnostic criteria, may be the presenting feature of this syndrome. Therefore all dermatologists should investigate the possibility of APS when cutaneous findings are related to venous or arterial thrombosis. The risk of thrombosis cannot be predicted, and therefore treatment is not initiated until a thrombotic event occurs. Indefinite anticoagulation is prescribed once a thrombotic event occurs. Prognosis depends on the severity of the clinical manifestations and so, knowledge of the presentation of this disease is important for early detection and prompt treatment to prevent life-threatening consequences of this catastrophic disease process.

Enhancement of polygalacturonase activity during auxin induced para nodulation and endorhizosphere colonization of Azospirillum in rice roots.

Effect of different auxins, namely, 2,4-dichlorophenoxyacetic acid (2,4-D), naphthalene acetic acid (NAA) and indole acetic acid (IAA) and Azospirillum brasilense bioinoculation on the enhancement of polygalacturonase (PG) activity in rice roots during para nodulation and endorhizosphere colonization of Azospirillum was studied under in vitro condition. It was observed that Azospirillum bioinoculation could augment PG activity of rice roots to a lesser extent without any root morphogenesis whereas auxin application together with Azospirillum bioinoculation enhanced PG activity of rice roots to a higher level which resulted in better root morphogenesis (para nodule) and endorhizosphere colonisation of A. brasilense. Among the three auxins tested, 2,4-D, even at lower concentration (0.5 ppm) enhanced the rice root PG activity, root morphogenesis and endorhizosphere colonization of Azospirillum while it was 2.0 ppm with NAA and variable with IAA. It is concluded that there is a positive correlation existing among PG activity, degree of root morphogenesis and endorhizosphere colonization of Azospirillum brasilense in rice roots and the degree of correlation is determined by the chemical composition, concentration and mode of action of the auxin utilised.

Evaluation of cyclosporine-A obtained from Tolypocladium sp. for immunosuppressive potential.

Cyclosporine-A obtained from an indigenous isolate of Tolypocladium sp. was evaluated for immunosuppressive potential by skin grafting in rats using the commercially available Sandimmune as reference at 15 and 30 mg/kg/day for a period of 14 days. The Sandimmune treated animal group showed 83 per cent acceptance of skin grafts while the test preparation treated group showed 67-83 per cent acceptance. The degree of nephro- and hepatotoxicity was comparable for both the preparations.