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. histolytica is discussed.

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. histolytica trophozoite and its degree of lesion-producing capacity in hamster liver suggest that the erythrophagocytosis assay in conjunction with the hamster liver inoculation test, can be useful in the identification of virulent E. histolytica isolates.

Experimental hepatic amoebiasis in inbred mice

A model of hepatic amoebiasis in two inbred strains of mouse (Swiss and BALB/c, has been developed by introducing Entamoeba histolytica-infected hamster liver tissue in between the adjacent liver lobes of mouse. It is expected that this model might be useful in studying various parameters of host-parasitic interactions and experimental chemotherapy of amoebiasis with relative ease.

A model of hepatic amoebiasis in random bred mice

This study describes a model of hepatic amoebiasis in random bred mice (MF2). Mice were infected by introducing liver tissue from hamsters (Mesocricetus auratus), containing about 5 X 10(4) trophozoites of Entamoeba histolytica, between adjacent liver lobes. Direct inoculation of xenic E. histolytica resulted in mortality within 24 h, whereas monoxenic and axenic strains failed to produce any lesions. Serial mouse liver passage resulted in increased lesion score, number of metastatic abscesses, and mortality. Metronidazole 150 mg/kg produced complete healing of the abscess. It is expected that this model will be useful to study host-parasite interactions, immunology and experimental chemotherapy of amoebiasis.

A specific solid-phase assay for the detection of immune complexes containing Entamoeba histolytica antigens

An assay specific for immune complexes containing Entamoeba histolytica antigens has been developed. Rabbit antibody specific for human gamma globulin is attached to a solid phase (nitrocellulose). During the first incubation step polyethylene glycol-precipitated immune complexes are bound to the rabbit antibody attached to the solid phase. In the second incubation step a radiolabelled rabbit antibody specific for Entamoeba histolytica combines with E. histolytica antigens in the complexes. Quantitation of the radiolabel provides a direct measurement of the level of specific immune complexes. The principle of the method has been verified using artificial soluble immune complexes prepared by mixing a pool of serum containing a high titre of anti-E. histolytica antibodies (greater than 1:2048 by hemagglutination assay) with the E. histolytica antigen. This antigen was prepared from axenically cultured NIH:200 strains of Entamoeba histolytica. Using sera from patients with clinical amoebic disease this method detected immune complexes containing E. histolytica in a high proportion of cases.

Unilateral giant lung metastasis of uterine leiomyosarcoma: diagnostic pitfalls in an unusual case

The lung is a frequent site of hematogenous metastases of many diverse tumors including soft-tissue sarcoma. The authors present a case with unilateral metastatic spread presenting as a giant lung mass, a pattern which, to the authors' knowledge, has not been reported in the literature.

Cardiac metastasis from adenocarcinoma of the lung. Echocardiographic-pathologic correlation

Metastatic cancer to the heart is difficult to diagnose ante-mortem. This report describes a patient with adenocarcinoma of the lung who presented with cardiac manifestations mimicking coronary artery disease. Two-dimensional echocardiography demonstrated massive cardiac infiltration with tumor, correlating with subsequent autopsy findings, which were also remarkable for endocardial implants and coronary artery emboli without myocardial infarction. Use of two-dimensional echocardiography may detect intracardiac tumor at an earlier stage.

Addison's disease due to metastatic carcinoma: the value of CT scan

A case of Addison's disease secondary to bilateral adrenal metastasis is reported. The adrenal metastasis were secondary to bronchogenic carcinoma and the diagnosis was made on the basis of the CT scan. The role of CT in the diagnosis of adrenal disease as well as the importance of including the adrenals in the chest CT scan for preoperative staging of bronchogenic carcinoma is discussed.