Detection of immune complexes in tissues of persons infected with Entamoeba histolytica.

Immune complexes were detected by radioimmunoassay in colonic tissue from 71 to 122 patients (58%) excreting Entamoeba histolytica cysts and in liver tissue from 5 of 16 of these patients. Complexes were also found in colonic tissue from 9 of 56 other patients (16%) who were not excreting cysts.

Zymodeme alteration of Entamoeba histolytica isolates under varying conditions.

Cysts of Entamoeba histolytica obtained from 2 asymptomatic subjects were cloned in vitro and the isoenzyme patterns and virulence of the cultures derived from them were determined. Incubation in Diamond's TYI-S-33 medium with Crithidia sp. for 80 d resulted in a change from zymodeme III to zymodeme II, with consistent virulence.

High cell surface hydrophobicity of virulent Entamoeba histolytica isolates.

Thirty isolates of Entamoeba histolytica were examined for their cell surface hydrophobicity. It was observed that increased hydrophobicity of the trophozoites was associated with lesion-forming ability in hamster liver, a higher rate of erythrophagocytosis and greater resistance to complement. The relationship of cell surface hydrophobicity to other virulence markers in E.

Virulence of nonpathogenic zymodemes of Entamoeba histolytica isolates from asymptomatic subjects in Calcutta, India.

1. The zymodeme and virulence of 31 Entamoeba histolytica isolates obtained from asymptomatic human subjects in Calcutta, India are described. 2.

Enhancement of virulence of Entamoeba histolytica by in vitro liver treatment.

Enhancement of the virulence of five strains of Entamoeba histolytica (three xenically maintained and two axenically maintained) was studied after in vitro incubation with normal hamster liver. Increased virulence was shown by the ability of a small number of liver-treated trophozoites to produce liver lesions in hamsters. Enhancement of virulence was positively correlated with increased resistance to normal hamster serum complement in vitro.

Study of Entamoeba histolytica isolates from Calcutta with special reference to their zymodeme, animal pathogenicity and erythrophagocytosis.

Entamoeba histolytica isolates, obtained mainly from asymptomatic human cyst passers, were tested for their in vitro erythrophagocytic activity and lesion-forming ability in hamster liver. Simultaneous zymodeme typing of the isolates showed that, along with the pathogenic zymodemes, a number of isolates having nonpathogenic zymodemes also produced liver lesions in hamsters and engulfed higher numbers of RBCs. The observed positive correlation between the rate of erythrophagocytosis of an E.

Ultrasonographic evaluation of carcinoma of the gall bladder.

Out of 6018 patients who were evaluated ultrasonographically for gastrointestinal problems over a four-and-a-half year period, 201 patients with a mean age of 53 years were diagnosed to have carcinoma of the gall bladder (3.3%). In 191 of these the diagnosis was confirmed by laparotomy and histopathological examination and in 3 other patients ultrasound guided fine needle aspiration cytology yielded malignant cells.