Immunopathology of experimental schistosome (S. Mansoni) egg granulomas in mice--possible defence mechanisms mediated by local immune complexes

A ten month experimental S. Mansoni infection was followed in mice by studying schistosome egg granulomatous inflammation, antigen and immunoglobulins deposits in the granulomata and the circulating antibodies. During the experimental infection it was demonstrated that while the granulomatous reaction matures there is a progressive restriction of the antigens to the miracidia. Furthermore, immunoglobulins, particularly IgG and C3 deposits were demonstrated in the granulomata. Our data support the concept that schistosome egg granuloma is a hypersensitivity high turnover granuloma that is particularly efficient in walling off the antigen. Whereas the granuloma is built up largely by a cell mediated immune reaction, antibody deposits are also found, probably functioning as a local humoral antibody barrier which allows a slow and progressive neutralisation of the antigens. Viewed as a whole, experimental schistosome egg granuloma might be considered as a mixed, chiefly cell but also humoral antibody mediated immune reaction.     

Sucrase-isomaltase: a marker of foetal and malignant epithelial cells of the human colon

The presence of sucrase-isomaltase (SI), a glycoprotein hydrolase normally restricted to the brush border membrane of the enterocytes of the small intestine, was investigated in tumours which developed in nude mice inoculated with six human colon carcinoma cell lines (HT-29, Caco-2, HRT-18, HCT-8R, SW-480, and CO-115). Foetal and normal adult human small intestines and colons were used as controls. SI was studied by (1) immunofluorescence with rabbit antibodies raised against purified human small intestine SI; (2) polyacrylamide gel electrophoresis and immunoblotting; and (3) determination of the enzyme activity. SI was antigenically present, and enzymatically active, in all the tumours derived from Caco-2 and HT-29 cells. The presence of the enzyme was associated with that of typical brush borders at transmission electron microscopy examination. SI was absent from the tumours developed with the other four cell lines, as well as from the normal adult colon mucosa. SI was also present and active in the colons of mid-gestation foetuses, ranging in ages between 20 and 28 weeks; it was absent from the colons of late-gestation foetuses. The presence of SI in tumours derived from two cell lines suggests that this enzyme is a marker, so far unsuspected, of certain human colon cancers, and that the differentiation pattern of these particular cancers closely resembles that of the foetal colon.     

Double-blind controlled study of the efficacy and pharmacological properties of heparan sulfate in patients with occlusive arterial disease of the lower limbs

The effect of a 60 day administration of 200 mg heparan sulfate (Hemovasal 100 b.i.d.) or 100 mg mesoglycan (50 mg b.i.d.) was assessed under double blind design in forty patients (thirty-six males and four females) with peripheral occlusive arterial disease with respect to pain-free walking distance and various haemorheological and haemostasiological variables, platelet aggregation and blood chemistry. The pain-free walking distance significantly improved with heparan sulfate (up 67% from baseline 200.0 +/- 22.5 m and up 34%, with mesoglycan from baseline 207.7 +/- 23.4 m). Heparan sulfate significantly stimulated fibrinolysis and reduced platelet aggregability: these findings suggest an action of heparan sulfate on the endothelial cells, thus reducing their thrombogenicity. The results of the study thus confirm the activity of heparan sulfate in peripheral vascular disease, correcting the conditions which constitute the basis of increased thrombotic risk.     

Plaque-forming cells in mice after experimental infection with Brucella abortus.

Cells producing antibody to brucella lipopolysaccharide were detected in spleens of mice infected with Brucella abortus 19 by a hemolytic plaque assay. The appearance of immunoglobulin M-producing cells preceded humoral antibodies. The primary plaques were observed 5 days after inoculation, and they were still present by day 70.     

Adjustable nylon ties for abdominal wall closure.

A study in 64 patients with a high risk of wound dehiscence or eviscerated wounds or in whom repeat laparotomies for peritoneal lavages due to sepsis were planned was accomplished using adjustable nylon ties for the closure of the abdominal wall, either as retention sutures or as one-layer sutures. The adjustable nylon ties are described, as well as the technique for placing and adjusting them. It is concluded that the adjustable nylon ties can substitute advantageously for the conventional retention sutures since the former are wider, easy to place, and can be readjusted to the point that they can be opened completely if it is necessary and then closed again. This is especially useful when repeat laparotomies for peritoneal lavages are required in patients with intra-abdominal sepsis.     

Two cases of listeriosis.

This is the second report of listeriosis in Sri Lanke. It is a disease with a changing clinical pattern. Most cases are from people at the extremes of age and from people with an underlying malignancy of the lymphoproliferative and renal transplant patients. But it is now being increasingly reported in previously healthy people. The two cases presented here are from previously healthy children. Both of them also manifested a rash which helped in the detection of the second case. A rash has not been described in the literature as characteristic or a common feature other than in neo-natal listeriosis.