Biomedical subjects

E A Kogan

Publications and source records attributed to E A Kogan.

94 records · Page 6Linked to original sources

PubMedDate not supplied

[Heterogeneity of pulmonary fibroblasts in tuberculosis].

Chronic inflammation and pneumofibrosis are the central events in tuberculosis morphogenesis. It was suggested that a certain type of fibroblasts may play a role in chronization of the inflammation and development of sclerosis in tuberculosis. Fibrous tissue from the foci of secondary tuberculosis (fibrous-cavernous tuberculosis and tuberculomas) of 35 patients were studied light- and electron-microscopically and immunohistochemically. (THY 1-)fibroblasts non-containing lipids and producing insulin-like growth factor 2 (ILGF 2), binding proteins 2 and 4 and epidermal growth factor receptors were found in the foci of secondary tuberculosis close to the granulomatous inflammation and in the new and scarrous fibrous connective tissue of the tuberculoma capsule and caverna walls. These fibroblasts are able for auto- and paracrine regulation of the proliferation of fibroblasts, epithelium and other cells in the inflammatory foci. (THY 1+) fibroblasts containing lipids were observed in the foci of old sclerotic changes among the rough collagen fibres. Thus, (THY 1-) fibroblasts probably play a key role in chronization of inflammation, proliferation and pretumorous dysplasia of pulmonary epithelium in secondary tuberculosis. (THY 1+) fibroblasts containing lipids may show more pronounced collagenesis and may persist under hypoxia condition in the collagenous scars for a long time.

Adult↗

PubMedDate not supplied

[Immunohistochemistry of biomolecular markers of early thyroid cancer].

Surgery material from 28 cases was studied. Thyroid adenoma differs from thyroid carcinoma by a lower level of expression of Ki-67 and bcl-2, while the mutated p53 expression is lacking. These indices may be used for early and differential diagnosis of thyroid carcinoma. Medullary carcinoma is a tumor with the highest malignant potential and p53 and bcl-2 may serve as markers of a higher degree of malignancy. Ki-67 may serve a marker of proliferative activity of tumors belonging to the same histological type. Thus, its high expression in follicular carcinoma is an index of a high proliferative activity of its cells, correlates with its rapid growth and should be taken into consideration in therapy and prognosis. Expression of bcl-2 clearly correlates with neuroendocrine differentiation of carcinoma and its highest expression was found in the medullary carcinoma as well as in the chromogranin positive cells of the papillary thyroid carcinoma. APUD amyloid deposits in medullary carcinoma and high levels of c-myc in adenomas indicate some genetic restructurizations in malignant and benign thyroid tumors.

Acute Disease↗

PubMedDate not supplied

[Immunohistochemistry of biomolecular markers of lung cancer].

104 surgery cases of non-small cell (NSLC) and small cell lung carcinoma (SLC) are studied. Oncoprotein bcl-2 is found in 49 out of 104 (47%) cases, more frequently in SLC (71%) than in NSLC (44%) and this correlated with carcinoma morphological malignancy. L-myc oncoprotein and EGFR were expressed practically in all cases, oncoprotein of the p53 mutated gene in 57% cases. The highest content of p53 was in SLC, large cell and poorly differentiated squamous cell carcinoma. Percentage of cells with mutated p53 statistically correlated with morphological malignancy of lung carcinoma. Oncoprotein of Rb gene was revealed in 51%, most frequently in squamous cell carcinoma (71%) and particularly in its well differentiated types. IGFII was found in 74% NSLC and in 100% SLC with cytoplasmic location in tumor cells; the level of expression was higher in SLC. IGFII 2 and 5 were more frequently observed in the foci of keratinization of squamous cell carcinoma. For the first time IGFP B3 was found not only in the cytoplasm but in the nuclei of tumor cells as well. There was a significant positive correlation between the content of IGFIBP3 in the nuclei of tumor cells and morphological malignancy (poor tumor cell differentiation, larger size and metastases). The mean number of proliferating Ki-67 positive cells was 24% but this figure was much higher (47%) in SLC. Squamous cell carcinoma is characterized by a more frequent and stronger expression of CD44 types 5 and 6 in the cytolemma and this may be considered as a marker of squamous cell differentiation of lung carcinoma.

Adult↗

PubMedDate not supplied

[Morphologic and molecular-genetic characteristics of carcinoma, adenoma and surrounding tissue of the thyroid gland].

The majority of thyroid tumors are not homogeneous histologically, this creating difficulties in interpretation of different carcinoma variants. The aim of the study was a complex comparative study of morphogenetic changes in carcinoma, adenoma and surrounding thyroid tissue. Surgical material from 48 patients operated because of nodular (multinodular) euthyroid goiter in Moscow Medical Academy in 1990-1997 was used. It was established that all the observations of early thyroid carcinoma diagnosed clinically as a nodular (multinodular) euthyroid goiter were represented by differentiated forms of thyroid carcinoma. Thyroid carcinoma was characterized by higher values of biomolecular markers as compared to adenomas and surrounding tissue. High values of c-myc expression in adenomas and surrounding tissue may indicate possible genetic rearrangements. A peculiar feature of carcinomas was the fact that deletions and replication errors in malignant tumors in this study were found simultaneously in the three genes investigated. As to different histological types of carcinoma, the most frequent deletions of the genes studied were observed in medullary and papillary-follicular carcinoma. High values of heterozygosity loss were found already in adenomas and surrounding tissues, this indicating the presence of the genetic changes already in the benign tumors and surrounding tissue.

Adenoma↗