[A histochemical study of diethylnitrosamine-induced altered liver cells in rats]

The histochemical changes of gamma-glutamyltransferase (gamma-GT), adenosine triphosphatase (ATPase), glucose-6-phosphatase (G-6-Pase) and ornithine carbamyltransferase (OCT) were studied in diethylnitrosamine (DEN) -induced and enzyme-altered liver cell lesions (Solt-Farber model) in rats. The number of altered liver cell foci tended to decrease after ceasation of 2-acetylaminofluorene (2-AAF); nevertheless, the number and size of the nodules increased rapidly within 20 weeks. The histochemical changes of most of the altered liver cell foci were focused on one or two kinds of enzyme activity (mostly gamma-GT and ATPase); while most of the nodules presented 3 or 4 kinds of histochemical changes, including OCT and G-6-Pase. It is concluded that some of those altered nodules of multi-enzyme changes might develop continuously to become tumors.

Immunopathological study on human cartilage allografts

The fate of human cartilage allografts and the mechanism of its kinetical development were studied histopathologically and immunohistologically. After transplantation, the grafts underwent necrosis, calcification and were partially invaded by osteoplastic tissue of the host and eventually replaced by bone tissue. Thus, the contour of the transplanted cartilage was kept partially by the living cartilage and the newly-formed osseous tissue. The grafts were surrounded initially by granular tissue and then by scar tissue, in which numerous T cells and a few macrophage infiltrates were noted. In T cells, T4+ lymphocytes predominated but T8+ cells accounted for a small number. B cells were not found within the infiltrates. Most of the infiltrating cells expressed 12 antigens, indicating that the majority of T cells were activated. It was concluded that T lymphocytes mediated cellular immunity played an important role. The chondrocytes of the cartilage did not express HLA I and II antigens before transplantation, but one month later, the living chondrocytes became HLA I and II antigens positive, and the antigen expression became stronger with the elapse of time; this might be induced by lymphokins, especially by interferon produced by the infiltrating lymphocytes. Such an expression of MHC antigens on chondrocytes might contribute to the further enhancement of immunorejection.

Invasion and metastasis of SY86B human gastric carcinoma cells in nude mice

A moderately differentiated tubular adenocarcinoma of human stomach, named SY86B, was successfully transplanted subcutaneously to nude mice of different genetic backgrounds (BALB/CA/PBI-nu, C57BL/6J.615/PBI-nu and ICR.BALB/CA/PBI-nu). The tumor has been passaged for 13 generations and the transplantability was 100%. The SY86B cells retained the capacity of invasive and metastatic growth in the nude mice and showed a high rate of metastasis to the regional lymph nodes and to such distant organs as the lungs, liver and pancreas. The overall rate of metastasis was 77.7%. The species of the nude mice, their age and sex apparently did not significantly affect the occurrence of metastasis. Tumor-bearing time and the aggressive character of the tumor cells themselves appeared important for the genesis of metastasis. This experimental model can provide a new approach to basic and clinical studies of cancer metastasis.

Histochemistry and electron microscopy in the diagnosis of small mucous cells in carcinoma of the stomach

One hundred and two cases of poorly differentiated adenocarcinoma were obtained from 71 surgical and 31 biopsy specimens of the stomach. These tumours produced both intracellular and extracellular mucins, which were demonstrated to be neutral mucins, N-acetyl sialomucins, sulphomucins and O-acetyl sialomucins. The majority of tumours (85.3%) secreted two or more kinds of mucins simultaneously, but only a small proportion (14.7%) produced a single kind of mucin. Ultrastructurally, three types of mucin granules were identified; these differed in shape and density. Tumour cells containing intracellular mucins or mucin granules were designated as mucous cancer cells and further subdivided into small, large and goblet mucous cells; tumour cells having neither mucins nor glandular differentiation were designated as undifferentiated cancer cells. These histochemical distinctions, supported by the electron microscopical observations, may be useful to demonstrate early malignant foci in gastric biopsies.

[Computer diagnosis of gastric dysplasia and program design]

Two step processes were taken in computer diagnosis of gastric dysplasia. 1. 5 measurement values of dysplastic glandular tube obtained by using image analysis system were taken as the basis for judging the degree of dysplasia. Three glandular tubes of dysplasia were measured in each case. 2. Computer pathology diagnostic program using BASIC language ran in IBM computer. 5 parameters were input into computer for three stage-diagnosis. The first stage: 5 parameters were counted basing on three models to obtain three values which reflected the objective feature of the same glandular tube from different aspects. The second stage: diagnosis of a dysplastic glandular tube was obtained depending on the three values judged synthetically. Variate 'N' was introduced for controlling the first and second stage diagnosis of the three glandular tubes. The third stage diagnosis started as soon as N = 3. The third stage: diagnostic values of three glandular tubes were balanced and analysed depending on diagnostic criteria to reach the final diagnosis.

[Morphologic measurement for diagnosis of gastric dysplasia]

Gastric dysplasia is a very important precancerous change recognized only by histological examination. The objective indexes of diagnosing the dysplastic change are hardly established. It is desirable to translate enumeration data of histopathology into measurement data in order to obtain objective measurement criteria for the diagnosis of gastric dysplasia. In this paper, three measurement indexes N/C, P1/D1 and P2/D2 are proposed. N/C represents the ratio of nucleus and cytoplasm, showing the cellular atypia. P1/D1 represents the ratio of outer perimeter of the measured glandular tube and diameter of an equivalent circle, showing the structural atypia. P2/D2 is the ratio of perimeter of the irregular shape by tracing the end of the nuclei near the lumen of the tube and diameter of an equivalent circle, showing both cellular and structural atypia. The results indicate that these three measurement criteria can be taken as the objective indexes for diagnosing gastric dysplasia and predicting its potential malignancy.

[Immunocytochemical study of monoclonal antibody 83YH2 in stomach cancer]

Using the avidin biotin complex (ABC) immunocytochemical stain, 97 cases of stomach cancer were examined for monoclonal antibody 83YH2. The positive rate was 82.47% (80/97) in stomach cancer with various types of differentiation. Some gastric epithelial cells and intestinal metaplastic cells near the cancer foci also showed weak positivity. But 83YH2 was not detected in normal human tissues. In the same stomach cancer cases, CEA test was also performed. The positive rate and distribution of CEA was almost similar to that of 83YH2, despite the fact that it was verified, by the immunoblock test, that 83YH2 was a different antigen. The results show that 83YH2 is an associated antigen of stomach cancer.