[Catheterization of the Eustachian tube in the combined treatment of exudative otitis].

The objective of the present study was to determine the amount of a medicinal agent entering the tympanic cavity during catheterization of the Eustachian tube in 26 patients presenting with exudative otitis and admitted for its treatment to N.I. Pirogov Clinical Hospital No 1, Moscow. The patients were managed by combined therapy in conjunction with catheterization of the Eustachian tube using radiocontrast matter (the iodine containing (76%) preparation trazograf having viscosity identical with that of dexamethasone). The administration of trazograf was followed by multispiral CT of the temporal bones. It was shown that trazograf penetrated into the tympanic cavity during catheterization of the Eustachian tube and accumulated inside it in 19.2% and 77% of the cases respectively. This finding suggests that the therapeutic effect in the patients presenting with exudative otitis is due not only to the direct action of the pharmaceutical product being used on the site of inflammation but also to the restoration of the draining and aerating functions of the course of Eustachian tube catheterization.

[Myogenic differentiation in experimental malignant schwannomas (an immunohistochemical and molecular genetic study of the "triton" tumor)]. / Miogennaia differentsirovka v éksperimental'nykh zlokachestvennykh shvannomakh (immunogistokhimicheskoe i molekuliarno-geneticheskoe issledovanie opukholi "triton".

Spontaneous myogenic differentiation was observed in 2 out of 15 monolayer cultures from schwannomas induced in BD1X rats by transplacental exposure to N-enthyl-N-nitrosourea (ENU). Cells were sorted following fluorescence-activating method with monoclonal antibody (Mab) 217c. Myotubes and numerous mononucleated cells no longer expressed the Schwann cell antigens 217c and S-100 protein, but rather revealed the presence of desmin, the alpha-sarcomeric form (alpha-sr) of actin, and the cell surface antigen specified by Mab RB21-7, a glycoprotein sharing an epitope with the neural cell adhesion molecule (N-CAM). Subcutaneous reimplantation of such cells into syngeneic animals resulted in the appearance of tumours composed of both S-100 positive Schwann cells and desmin and alpha-sr-actin positive rhabdomyoblasts, thus closely resembling the human "triton" tumour. With the use of the polymerase chain reaction and allele-specific oligonucleotide hybridization, DNA isolated from individual myotubes was analysed for the presence of a T-->A transversion mutation at nucleotide 2007 of the neu gene, which is diagnostic of ENU-induced rat schwannomas. All of the amplified DNA isolated contained the mutant neu allele, thus providing direct genetic proof for the capacity of mammalian neuroectodermal cells for myogenic differentiation.

[The early stages of the morphogenesis and tissue lineage of an experimental malignant fibrous histiocytoma]. / Rannie stadii morfogeneza i tkanevaia priroda éksperimental'noi zlokachestvennoi fibroznoi gistiotsitomy.

Morphologically atypical cells were first detected on the 98th day after subcutaneous implantation to rats of a paraffin pellet containing 2 mg of 7,12-dimethylbenz(a)anthracene (DMBA). These cells subsequently formed groups and finally gave rise to malignant fibrous histiocytomas. Early atypical cells were located between proliferating fibroblasts and histiocytes in the center of a fibrous capsule surrounding the DMBA-pill. They exhibited a smooth cell surface, dilated rough endoplasmic reticulum, multiple Golgi complexes, and were often associated with newly formed collagen. These cells incorporated 3H-thymidine and 3H-proline intensively, and showed weak acid phosphatase activity, but no features typical for macrophages (microvilli, numerous lysosomes, high activity of acid phosphatase, nonspecific esterases, antigens recognized by monoclonal antibodies ED1 and OX-42, vital staining with trypan blue). Atypical cells also did not differentiate into muscle cells (no expression of desmin and the alpha-sarcomeric form of actin), nor into Schwann cells (no expression of S-100 protein). No point mutation of the neu gene at nucleotide 2007, which is specific for N-ethyl-N-nitrosourea and DMBA-induced malignant rat schwannoma cells, was detected by polymerase chain reaction-restriction fragment length polymorphism analyses of microscopically selected regions of individual 7 micron cryostat sections. These results support the view that malignant fibrous histiocytoma is derived from immature fibroblasts exhibiting pronounced phenotypic diversity during later stages of carcinogenesis.

[The morphogenesis and histogenesis of an experimental malignant fibrous histiocytoma]. / Morfogenez i gistogenez éksperimental'noi zlokachestvennoi fibroznoi gistiotsitomy.

Light and electron microscopy, histochemistry, histoautoradiography and vital staining were used to assess changes occurring in subcutaneous connective tissue surrounding a DMBA-containing pill in rats, samples being obtained at 2-week intervals until malignant fibrous histiocytoma became apparent. Initial tumor lesions developing against the background of alterative-inflammatory and reparative changes included apparently atypical pleomorphic cells showing cytologic signs of malignant transformation which remained virtually unchanged in developed sarcoma. The study, therefore, failed to identify the stage of "presarcoma". A complex of morphologic and functional characteristics of the atypical cells revealed their fibroblastic nature. Progression of tumor was associated with appearance of cells of histiocytic pattern (as evidenced by high activity of acid phosphatase and non-specific esterases, thin villus-like outgrowths of cellular membrane and well-developed Golgi complex) which pointed to pronounced structural and functional variability of poorly-differentiated neoplastic fibroblasts. Tumor revealed xanthomatous and multinuclear giant cells, too. Malignant fibrous histiocytoma is, therefore, poorly-differentiated polymorphocellular sarcoma of fibroblastic origin.

[Clinico-echocardiographic studies of the state of the heart in vibration disease]. / Kliniko-ékhokardiograficheskoe issledovanie sostoianiia serdtsa pri vibratsionnoi bolezni.

Established was the rate of interventricular septum asymmetrical hypertrophy and left auricle exstasia in vibration disease patients as a result of local vibration. The left ventricle myocardium contraction in major parameters (ventricular ejection, maximum ejection, ejection time and volume, the myocardium circular contraction rate and anterior-posterior contraction, systolic ejection rate) were not affected to a significant degree. The left ventricular systolic function was tending to decrease in vibration disease cases combined with IHD and AH. Desirability of using EchoCG in combination with load testing was proposed for the differential diagnosis of metabolic coronary lesions of the myocardium in vibration disease patients.

[The ultrastructure and histochemical characteristics of the cells of malignant fibrous histiocytoma in rats]. / Ul'trastruktura i gistokhimicheskie osobennosti kletok zlokachestvennoi fibroznoi gistiotsitomy u krys.

Samples of tissue from malignant fibrous histiocytoma of rats induced by subcutaneous injection of paraffin pill-enclosed DMBA were studied for localization of acid phosphatase and non-specific esterases (15 samples) and cell ultrastructure (10). Tumours showed cellular heterogeneity consisting of 5 types of cells: histiocyte-like, fibroblast-like, giant multinuclear xanthomatous and undifferentiated. Acid phosphatase and non-specific esterases were found both in histiocyte-like and fibroblast-like cells which means that those enzymes are not the specific markers of tumors arising from monocytic-macrophagal system. Histochemical and ultrastructural features of experimental malignant fibrous histiocytoma were similar to those of its human analogue.

[Characteristics of the production of chorionic gonadotropin by the cells of trophoblastic tumors (immunohistochemical research)]. / Osobennosti produktsii khorionicheskogo gonadotropina kletkami trofoblasticheskikh opukholei (immunogistokhimicheskoe issledovanie).

An immunohistochemical investigation of chorionic gonadotropin (CGT) in normal placental, hydatidiform mole and choriocarcinoma tissues was undertaken. Cyto- and syncytiotrophoblast both were shown to produce the hormone in normal and tumor trophoblast; the rate of synthesis increased in proportion to the degree of cell elements differentiation, except for very large elements of syncytiotrophoblast with numerous pycnotic nuclei which were found to contain either only traces of response to CGT or none at all. The percentage of syncytiotrophoblast--produced hormone progressively increased in the succession of the placenta--hydatidiform mole--choriocarcinoma. No significant difference in the levels of immunohistochemically--identified hormone was found in the hydatidiform mole and choriocarcinoma.

[Morphology of experimental malignant fibrous histiocytoma]. / Morfologiia éksperimental'noi zlokachestvennoi fibroznoi gistiotsitomy.

The microscopic structure of tumors induced in rats by subcutaneous injections of 7,12-dimethylbenz(a) anthracene (DMBA) was studied. Most of them (90%) were histologically identical to malignant fibrous histiocytoma (MFH) in humans. This experimental model is useful in MFH morphogenesis and histogenesis studies in connection with the high frequency and synchronicity of tumor development and distinct localization of tumor at the site of injection.

[Immunohistochemical study of malignant fibrous histiocytoma]. / Immunogistokhimicheskoe izuchenie zlokachestvennoi fibroznoi gistiotsitomy.

Malignant fibrous histiocytomas (MFH) and other soft-tissue tumors were examined immunochemically (by the peroxidase-antiperoxidase technique) for the presence and location of alpha 1-antitrypsin (alpha 1-AT) and alpha 1-antichymotrypsin (alpha 1-ACT). alpha 1-AT and alpha 1-ACT were found in substantial amounts in 19 and 20 of the 20 MFH tumors examined, respectively. In the other soft-tissue tumors, they occurred inconsistently and in less than 50% of cells, mostly those with signs of damage. It is concluded that assays for alpha 1-AT and alpha 1-ACT may aid in the diagnosis and characterization of malignant fibrous histiocytoma.

[Malignant schwannoma with the microscopic features of a malignant fibrous histiocytoma]. / Zlokachestvennaia shvannoma s mikroskopicheskimi chertami zlokachestvennoi fibroznoi gistiotsitomy.

A case of malignant schwannoma is described in which the primary tumor showed morphologic signs of malignant fibrous histiocytoma, but these were not confirmed by immunohistochemical assays which were negative for markers of histiocytic tumors such as alpha 1-antitrypsin and alpha 1-antichymotrypsin. In the recurring tumor, typical palisade structures were found. Difficulties attending the diagnostic differentiation of these two tumors are discussed. It is concluded that histogenetic characteristics of malignant fibrous histiocytomas must be known to be able to establish more precise criteria on which the differentiation may be based.

[Morphometric analysis of the free stromal cells of nevi and malignant melanomas]. / Morfometricheskii analiz svobodnykh kletok stromy nevusov i zlokachestvennykh melanom.

A morphologic study of 114 cases of pigmented skin tumors was carried out. The cases were divided into 5 groups on the basis of the degree of nevus proliferation and depth of melanoma invasion. The percentage and correlation between different types of free stromal cells were obtained for different skin zones in 6 cases of each group. Correlation analysis established the set character of cell cooperation at different stages of tumor growth. Diagrams illustrating correlations between free stromal cells and pigmented formations patterns are discussed. The results of the study may be helpful in running diagnostic tests of nevi for malignancy as well as identifying the depth of melanoma invasion whenever visual morphologic examination is insufficient.