Effect of laccase from Hypsizygus ulmarius in decolorization of different dyes.

The objective of the study was to check the laccase (purified from Hypsizygus ulmarius) for decolorization of different dyes. The purified laccase from Hypsizygus ulmarius was studied for its decolorization of different dyes (Remazol brilliant blue R (RBBR), Alizarin red, Congo red, methyl orange and methyl violet). The results indicated that the percent of decolorization was increased when the time course and enzyme concentration was increased. The purified laccase showed maximum amount of decolorization in RBBR (85%) and followed by Methyl Orange (75%), Alizarin Red (73%), Methyl Violet (72%) and Congo Red (69%) without any additional redox mediator which suggest that this enzyme could be used in industries for effluent treatment.

Clinicopathologic spectrum of gastro intestinal stromal tumours - Experience at a tertiary care center.

Context: Accurate diagnosis of Gastrointestinal stromal tumors (GISTs) and categorization of risk groups is crucial in the wake of targeted drug therapy. Aim: This study was undertaken to obtain insight into the clinicopathologic features of GISTs. Materials and Methods: Retrospective study of 20 cases of c-KIT (CD 117) positive GISTs .Various histologic parameters were studied. Immunohistochemical panel included CD-34, Smooth muscle actin, S-100, Desmin, and Vimentin. Risk categorization was done as per standard protocol. Clinical details and follow up were retrieved from cases files. Results: Of the total 20 cases, 15 were males. The mean age of presentation was 52 years. 50 % of the cases presented with gastro intestinal bleeding .The cases were categorized as high risk (60%), intermediate risk (20%), low risk (15%) and very low risk (5%). Stomach and small intestine were commonly involved and in 6 of the cases there were metastatic nodules in the mesentery/omentum/ peritoneum. Spindle cell morphology was the commonest histological pattern (55%). Nuclear pleomorphism, perivascular whorling, mucosal and fat invasion were seen only in the high risk group. CD-34, SMA and S-100 were positive in 90%, 30%, and 10% of the cases, respectively, with consistent Desmin negativity. Conclusions: Cases of GISTs in our clinical setting presented a decade earlier and mostly belonged to the high risk group. Certain histological features such as necrosis, and perivascular whorling were more commonly associated with the high risk groups.