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Biomedical subjects

J Tóth

Publications and source records attributed to J Tóth.

At least 145 records · Page 8Linked to original sources
PubMed1979

Ultrastructure of the hepatic perisinusoidal cells in man and other mammalian species.

Perisinusoidal (P.S.) cells occurring in the spaces of Disse in the livers of normal cats, dogs, miniature pigs, albino rats, human adults and children were examined by electron microscopy. The ultrastructural details of the P.S. cells and their topographic relationships with hepatocytes, sinusoidal lining cells and reticulum fibers are described. Species differences between P.S. cells were primarily a dissimilarity in lipid content: the main ultrastructural features were the same in all species studied. The P.S. cells of the rat liver displayed only low endocytotic activity, and no phagosome formation following intravenous administration of horseradish peroxidase. The close topographic relationship of the P.S. cells with the intralobular reticulum fibers was reminiscent of the intimate connection between fibroblasts and collagen fibers, or, in cat liver, of the reticulum cell--reticulum fiber association seen in lymphoid organs. Fibroblasts were not found inside the hepatic lobules. These findings support the conclusion that the reticulum fibers of hepatic lobules are produced by perisinusoidal cells which, however, display also other functions.

Adult↗
PubMed1979

The role of myoepithelial cells in the morphogenesis of induced mammary tumours.

The localization and cytomorphology of myoepithelial (ME) cells and their role in the morphogenesis of the mammary gland tumours of Wistar rats induced by 7,12-Dimethylbenz-a-anthracene-DMBA- were studied. Cells which do not participate in secretion and contain cytoplasmic myofibrillar bundles in a typical arrangement are considered to be of ME origin. In the histogenesis of induced mammary gland tumours no difinite role can be attributed to mature ME cells or their precursors. Decreased differentiation is associated with reduced numbers of ME cells. No ME cells can be detected in the anaplastic, stromafree portions of the solid tumour. The sarcomatous component of the induced carcinosarcomas originates from connective tissue. ME cells may give rise to leiomyoma-like tumours comparable with the human benign mammary myoepithelioma. The atrophic areas of mammary gland tumours consisted mostly of preserved ME cells. The ME cells of induced mammary gland tumours were, in every respect, identical with the normal ME cells of control mammary glands.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1979

Aetiological studies of hypospadias in Hungary.

A complex aetiological (epidemiological, teratological and genetic) study was made in 294 index patients with simple isolated hypospadias. The epidemiological study conducted by the help of personal interviews of the mothers revealed a higher frequency of index patients among children born between August and December, among twins, mainly monozygotic, and finally in the lower birth weight groups and among first-borns. The teratological study showed a higher frequency in mothers of index patients who had had sex hormone treatment, mainly progestogen, before the 16th gestational week. This seems to indicate the aetiological role of fetal androgen deficit caused by the regulation disturbances of human choriogonadotropin. The genetic family study completed by personal examination of first-degree male relatives showed a familial clustering (4.0% versus a point prevalence of 0.44% in live-births). Both the pattern of affected relatives (h2 values 0.62 +/- 0.21 and 0.72 +/- 0.33 in fathers and brothers, respectively, not differing significantly from each other) and further characteristics (other malformations were not frequent in relatives) correspond to the multifactorial-threshold model.

Abnormalities, Drug-Induced↗
PubMed1977

Benign human mammary myoepithelioma.

A leiomyoma-like, multifocal tumour developed from intraductal papillomatosis in the breast of a 42 year old woman. The spindle-shaped tumour cells were examined by light, electron and polarizing microscopy, which revealed that they originated from immature "precursor" myoepithelial cells. The author suggests that the tumour be called "myoepithelioma". From the morphological characteristics of the tumour the myoepithelial cells appear to be capable of producing leiomyoma-like benign or malignant tumours. The role that has been attributed by some to the myoepithelial cell in the production of epithelial tumours is problematical, in the light of the present finding.

Adult↗
PubMed1977

Eosinophil predominance in Hodgkin's disease.

Re-evaluating 327 Hodgkin's disease biopsy specimens, 10 cases with dense eosinophilic infiltration, amounting to more than 50% of the cell population, have been found. This phenomenon of eosinophilic predominance, occurred mainly in the fibrotic types of Hodgkin's disease. The survival time of patients with eosinophilic predominance was significantly shorter than that of the controls. The possible role of eosinophils in Hodgkin's disese has been discussed.

Adolescent↗
PubMed1977

[Diseases associated with double ureters].

Seventy-four children with double ureters were observed in the past three and a half years, out of whom 12 were operated because of vesico-ureteral reflux, 2 for lithiasis, 6 for hydronephrosis and 15 because of ureterocele, while in 10 cases operation was indicated by ectopic ureters opening into the area of the vulva. In these diseases intercurrent infection represents the greatest danger which might cause in children a toxic, septic and dystrophic state.

Congenital Abnormalities↗
PubMed1977

A full stochastic description of the Michaelis-Menten reaction for small systems.

A method is presented to solve the Komogorov-equations for the stochastic model of the Michaelis-Menten reaction. The results are given for the case when only one enzyme molecule is involved in the reaction and can be extended to the case when a few enzyme molecules react. The important differences between the results of stochastic and deterministic treatment are emphasized, and their possible biological implications are discussed. Beside the exact solution of the time course of the irreversible reaction also the equilibrium is described for the reversible reaction. The method provides means for studying other biologically important reactions assuming stochastic behaviour. A comparison is made also with the steady state approximation.

Enzymes↗
PubMed1977

Post mortem detection of early myocardial infarction by determination of the tissue K+/Na+ ratio.

The K+/Na+ ratio was determined in myocardial specimens obtained post mortem from a total of 90 patients. The ratio was 1.0 or higher 25 cases in which there was firm evidence against myocardial infarction, and 0.7, or less in 30 cases with grossly visible signs of myocardial narcosis. The remaining 35 cases were suspect of myocardial infarction on the grounds of either clinical observation or sudden death, without gross change. Out of these the K+/Na+ ratio was above 0.7 histological evidence of myocardial infarction was absent, but other changes accounting for death were present in 17 cases. In another 16 cases a K+/Na+ ratio of 0.7 or less was the sole indication of myocardial infarction, and any other change likely to be responsible for death was absent. In two further cases a false negative result was obtained for the K+/Na+ ratio, owing in all probability to some technical error. The findings suggest that determination of the myocardial K+/Na+ ratio is a great aid in detecting early myocardial infarction. The technique is not affected by post mortem autolysis, and is simple enough for routine use.

Adult↗
PubMed1977

[Causes of death in cancer patients].

Causes of death of 260 tumorous patients autopsied in 1974 were analyzed. Most common causes were inflammation and tumorous and non-tumorous organ insufficiencies; the others, in order of decreasing incidence, massive tumorous dissemination, infarct and haemorrhage. Pneumonia was predominating over the inflammatory causes although peritonitis and sepsis were also not rarely encountered. Death due to inflammation occurred most frequently in cases of myeloid-lymphoid, urogenital and gastro-intestinal tumours and in postoperative states. The incidence of insufficiencies due to tumorous or non-tumorous origin differed but slightly. Of the various organ insufficiencies, massive hepatic metastases, occlusion of the biliary duct and cardiac failure were the most common. In cases of tumors of the small pelvis, compression of the ureters led most often to death. Massive dissemination was observed most of all in breast and ovarian carcinomas. Myeloid-lymphoid tumors led to death through extensive organ infiltration in about one thirds of the cases. After hearth infarction, venous thrombosis was often followed by pulmonary embolism, however, coronary occlusion was also not rare. Death due to haemorrhage originated from acute or chronic ulcers of the gastrointestinal tract or from vascular invasion of tumors in the head and neck regions or from thrombocytopaenia induced by cytostatics.

Humans↗
PubMed1977

[Clinicopathological experiences in oncologic diseases].

Authors on the base of the study of clinical history and autopsy protocols of 260 patients died in 1974 in the Institute of Oncology of Hungary from oncological diseases established, that the proportion of decised younger 30 years and the number of those older 70 years increased in comparison with 1964. In the autopsy material the most frequent were tumours of the lymphoid-myeloid system, then followed the frequency of the tumours of the breast and urogenital tract, the least frequent were the tumours of the gastrointestinal tract. Number of the primary multiplex tumours during the last 10 years increased from 1,5 per cent to 5,5 per cent. In 23,5 per cent of the cases medica negligence or that of the patient itself could be proved. The clinical and the pathological diagnosis did not correlate in 35,9 per cent of the cases studied. The most common unrecognized complication was pneumonia. Surgical treatment appeared to be most effective in cases of the cancer of the breast. The average age of the patients suriving for a longer period after the operation was 62,8 years, which seems to evidence, that prognosis of oncological diseases in older ages is better than in younger. In comparison with the data in 1964 number of cases with five year surviving increased by 3,7 per cent. This was striking first of all in cases of lymphoid-myeloid tumours.

Humans↗
PubMed1976

Demonstration of hepatitis B surface antigen by orcein staining in paraffin sections of cirrhotic liver.

Blood and liver from 44 and 30 patients, died in cirrhosis and other diseases, respectively were tested for the presence of HBSAg. Blood samples obtained at autopsy and in seven cirrhosis cases also before death were tested for HBSAg by counter-electrophoresis. Detection of HBSAg in hepatocytes was carried out in paraffin sections by the modified orcein staining technique of Shikata et al. Ten of 14 HBSAg seropositive and 2 of 30 HBSAg seronegative cirrhotic patients had orcein positive hepatocytes, which were not found in any liver specimen from the 30 non-cirrhotic seronegative patients. The orcein positive substance localized in the cytoplasm of hepatocytes, less often it was also seen in a few Kupffer cells. The hepatocellular carcinoma cells present in part of the livers studied did not contain any orcein positive substance. Histological changes in the cirrhotic livers showed morphological indication of the presence of HBSAg, except on staining with orcein. The modified orcein staining technique is a simple, handy procedure for use in any routine pathological laboratory and has the additional advantage of detecting HBSAg also in stored paraffin blocks.

Carcinoma, Hepatocellular↗
PubMed1976

[Transurethral resection of bladder neoplasms].

The technique of removal of bladder tumours is discussed on the basis of experience with transurethral resection performed on 200 patients suffering from bladder tumour (113 benign and 87 malignant tumours). The indications for the intervention are as follows. With benign tumours, resection has to be given preference over exposure. When malignant tumours are operable and situated on the mobile part of the bladder, radical surgery is recommended. When the tumour is in some other position, transurethral resection is the procedure of choice.

Female↗