A histopathological study of liver and biliary remnants with clinical outcome in cases of extrahepatic biliary atresia.

Context: The indicators of poor prognosis in cases of extrahepatic biliary atresia (EHBA) continue to remain controversial. Aims: To correlate the histopathological findings of wedge biopsy from liver and tissue obtained from the shaving at the porta hepatis, during hepatic portoenterostomy, with the clinical outcome. Materials and Methods: All cases of EHBA surgically treated in our hospital from 1995 to 2006 have been reviewed. Wedge biopsies of the liver and biopsies from the porta hepatis were analyzed with hemotoxylin-eosin stains and immunohistochemistry. The parameters correlated with clinical outcomes were - presence of large bile ducts ( > 150μm diameter) in the portal tissue plaque, degree of fibrosis (semi-quantitative; graded as mild, moderate and severe), presence of ductal plate malformation (DPM) and age at operation. Results: The proportions of patients with small or large ductal diameter who remained clinically controlled (serum bilirubin < 1.5mg/dl with no evidence of end stage liver failure) were 39% and 66.6% respectively (P=0.44). There was a highly significant correlation between the extent of fibrosis and clinical outcome. Mild, moderate and severe fibrosis resulted in clinical control rates of 78.5%, 34.4% and 24% respectively (P=0.001). Ductal plate malformation was seen in 15% of our cases and was uniformly associated with poor outcome. A non-significant trend towards poorer outcome was seen with increasing age at surgery. Conclusions: Histopathological correl ations with clinical outcome in EHBA have been rarely reported from the Indian subcontinent. A greater degree of fibrosis at the time of hepatic portoenterostomy and presence of ductal plate malformation is associated with a significantly poorer clinical outcome.

Physical demonstration of a high molecular weight bacteriocin plasmid in Vibrio cholerae by genetic transformation process.

Bacteriocinogeny was transferred at high frequencies from bacteriocinogenic (Bac+) V. cholerae strains to non-bacteriocinogenic (Bac-) recipients in the in situ genetic transformation system on agar surface. DNA extracted from samples of growth of bacteria transformed to Bac+ were obtained at 2 h intervals following contact with the sterile agar surface where the donor had grown previously. This showed acquisition of a high molecular weight plasmid which could be physically demonstrated best in the 6 h sample of the Bac+ transformants; their 4 h samples failed to show this specific plasmid, while it was demonstrable only as a faint band in the 8 h samples.

'DNA' as contaminants in antibiotics and its capacity to transform bacteria to drug resistance.

DNA/and deoxyribose sugars were detected in streptomycin (Sm), kanamycin, polymyxin, penicillin G, ampicillin, methicillin, cloxacillin and mitomycin C in small amounts/traces. Stained DNA could be feebly visualized directly in Sm run in agarose gel, which improved after its separation and concentration. These DNA materials were DNase sensitive, RNase and pronase resistant, and appeared to consist of fragments, c. less than or equal to 6 Mdal; this could repeatedly transform to SmR several recipient enterobacteria and vibrios; E. coli C600 and S. typhi 57, after such transformation revealed similar plasmid DNA bands that were absent in their wild-types. G + C mole% of plasmid and chromosomal DNA of recipient (57) along with that of Streptomyces griseus reference strain, suggested an extraneous origin for the plasmid DNA.