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Biomedical subjects

Z Schaff

Publications and source records attributed to Z Schaff.

At least 73 records · Page 4Linked to original sources
PubMed1990

Fine structure of hepatocytes during the etiology of several common pathologies.

Hepatocytes respond to injury by a few basic pathological reactions that are reflected in cell death, different types of degeneration, regeneration, or tumorous transformation. At the ultrastructural level, alterations of cell organelles can be observed in different combinations as a result of the injury, depending on the etiological agent(s) or pathological conditions developed. Nuclear bodies, dilation and fragmentation of rough endoplasmic reticulum (rer), swelling of mitochondria, and an increased number of lysosomes occur during acute viral hepatitis. The core and surface components of the hepatitis B virus can be localized in the liver cells in chronic hepatitis and in carriers. Close contact of hepatocytic and lymphocytic cell membranes were observed in chronic active hepatitis. Hepatocytes surrounded by an increased amount of collagen fibers are characteristic of cirrhosis. Loosely arranged, fine fibrils or condensed forms of Mallory bodies are pathognomic for alcoholic injury. A wide spectrum of alterations are noted after drug treatment: the proliferation of smooth endoplasmic reticulum (ser) as an adaptive phenomenon, focal or complete necrosis of the cell, inflammation, and the like. The fine structural analysis of hepatocytic inclusions in storage diseases has a differential diagnostic value. The storage of copper and other elements can be measured by x-ray microanalysis. The study of the hepatocytic differentiation in liver tumors is highly important in establishing the diagnosis and in proving the hepatocytic origin of the tumor.

Humans↗
PubMed1990

Effect of free radicals in ischaemic renal failure in the dog.

After a 30-minute control period ischaemia was evoked in dogs under Nembutal (30 mg/kg, i.v.) anesthesia, by clamping the left renal artery for 45 minutes. This was followed by a 90-minute reperfusion period when diuresis, GFR, PAH clearance, sodium and potassium excretion, malondialdehyde level in the plasma of the renal vein and SOD enzyme activity of the erythrocytes in renal venous blood were determined. Besides the control group (n = 6), the following treated groups were investigated: 1. Allopurinol (n = 7) in a dose of 100 mg/kg, given orally for two days, 2. Silibinin (n = 6) in a dose of 4 mg/kg/hour, given into the renal artery, 3. MTDQ-DS (n = 6) in a dose of 150 mg/kg/hour, given intravenously. 4. SOD (n = 4) 4 mg infusion (initiated 1 minute prior reperfusion). In the first 15-minute period following reperfusion GFR was 21%, cPAH 29% and sodium and potassium excretion 67 and 42% of the values of the contralateral kidney, respectively. Renal function improved gradually during the 90 minutes of reperfusion, and the above-mentioned parameters reached 59, 57, 65 and 76% of the corresponding control data. Increase of malondialdehyde level in the venous blood of the kidney during reperfusion might have been indicative of the production of free radicals; the difference, however, was not significant statistically. The administrations did not lead to considerable change in any of the parameters investigated. No difference could be demonstrated by histological methods between the kidneys of the treated and untreated animals. The compounds studied are thought to be free radical scavengers; in the present work, however, no protective effect could be demonstrated.

Acute Kidney Injury↗
PubMed1990

[Fibrolamellar liver carcinoma].

Four fibrolamellar liver carcinomas were surgically removed and were postoperatively examined. Three patients are alive roughly three years from surgery, and there are no signs of imminent recurrence, while the fourth case was diagnosed only two months back. The carcinomas had developed in non-cirrhotic livers which also produced negative responses to serological tests for hepatitis B. In flow cytometry, DNA indices were indicative of diploidy in two cases and aneuploidy in the other two. The highest DNA index value was recorded from the smallest tumour which could be assigned to the category of "minute HCC". No correlation was found to exist either between age, sex, and DNA index. Positive CEA reaction was immunohistochemically recorded from few tumour cells, whereas negative AFP responses were exhibited by all four tumours. Appearance of AAT in tumour cells was detected in three cases. High degree of differentiation, similarity between tumour and liver cells, and oncocytoid nature of cells were revealed by optical light and electron microscopy. This high degree of differentiation was additionally confirmed by two factors: glucose-6-phosphatase activity was preserved in all four tumours, adenosinetriphosphatase activity was histochemically detectable from certain points of the tumour cell membrane. Gamma-glutamyl-transpeptidase activity, too, was very strongly pronounced in all tumour cells, which, however, cannot be interpreted as a sign of differentiation. Membrane-bordered "dense-core" granules were visible in few tumour cells in two cases. Intensive granular serotonin reactions were immunohistochemically recorded from the majority of tumour cells in the same cases. Our histochemical and ultrastructural parameters have produced clear-cut evidence to the hepatocyte nature of FLC cells. Yet, the presence of secretory granules and positive serotonin reaction might possibly support the assumption that the FLC originates from those pluripotent cells of the liver which may develop in two directions, depending on the individual case, to become either hepatocytes or neurosecretory cells.

Adolescent↗
PubMed1990

[The effect of D-penicillamine on experimental liver cirrhosis induced by CCl4].

Authors examined the effect of D-penicillamin (Pw) on liver cirrhosis induced by chronic CCl4 and phenobarbital (Pb) treatment in Fischer 344 rats. Morphometric analysis of quantity of connective tissue fibres did not show decrease on the effect of Pe treatment. Quantity of hydroxiproline, which is one of the parameters of coll ahen decrease, did not change significantly on effect of drug, but only compared to CCl4 and Pb treated control. Quantity of glycosaminoglycan showed increase following Pe treatment. Lymphocyte stimulation by Con-A was different in CCl4 and Pb and Pe treated groups, respectively. According to our examinations in case of liver fibrosis cirrhosis induced by CCL4-PB treatment in rats the Pe treatment proved to be unsuccessful. It seems that Pe is effective only in forms of cirrhosis accompanied by significant copper accumulation, by decrease of toxic effects of copper.

Animals↗
PubMed1990

[Pathobiology of human primary benign and malignant liver tumors].

Authors elaborated 35 surgically removed tumors of liver by morphological and biochemical methods. From tumors 5 proved to be hepatocellular adenoma (HCA), 12 to focal nodular hyperplasia (FNH) and 18 to hepatocellular cancer (HCC). On the basis of enzyme histochemical and biochemical examinations, HCA is characterised by "normal" enzyme pattern. By the above method, FNH can be divided into two groups, characterized with "normal" and "abnormal" (tumor-like) enzyme change, while HCC proved to be very heterogeneous. Majority of HCA and FNH cases, according to data gained by flow cytometer, were of diploid DNA content. In majority of HCC cases, DNA diploid was aneuploid, but in three cases normal DNA content was observed. The above mentioned examination revealed several different characteristics of human hepatic tumors, compared to experimentally created tumors of liver.

DNA, Neoplasm↗
PubMed1989

[Current diagnostic method for saccharose-isomaltose malabsorption].

The authors present the cases of 4 children who suffered from saccharose-isomaltose malabsorption. The clinical symptoms developed following artificial feeding. The diagnosis was made by the histological examination of small intestine samples and with the simultaneous measurement of disaccharide enzyme activity. The histological picture and activity of lactase enzyme were practically normal. The saccharose H2 breath test gave only in 1 case positive result. The treatment of the children required saccharose-free diet. The tolerance showed no improvement during the treatment.

Child, Preschool↗
PubMed1989

Ethanol treatment inhibits the development of diethylnitrosamine-induced tumors in rats.

Effect of ethanol (20% in drinking water) or acetone (1% in drinking water) treatment was investigated on N-diethylnitrosamine (DEN), acetyl-aminofluorene (AAF) and partial hepatectomy (PH) induced hepatic tumors in rats. Simultaneously with the morphological detection of foci and nodules in the liver of the sacrificed rats, the activities of isozymes of cytochrome P450IIE gene subfamily responsible for the oxidation of ethanol or acetone (as aniline hydroxylase) and also the activity of aminopyrine N-demethylase were determined. Nodules could be detected after DEN, AAF and PH treatment with and without combination with acetone, however nodules did not developed in ethanol treated animals even 6 months after the DEN injection. As expected acetone or ethanol selectively increased the activity of aniline hydroxylase without a general induction of P-450 enzymes. It is suggested that the induction of P-450IIE isoenzymes per se is not connected to the preventive effect of ethanol on DEN induced carcinogenesis.

Animals↗
PubMed1988

Atrial natriuretic peptide directly inhibits corticosteroid biosynthesis in human aldosterone-producing adenoma.

The effect of human atrial natriuretic peptide (hANP) on aldosterone, 18-OH-cortisterone, corticosterone, deoxycorticosterone, and cortisol secretion was examined in isolated human aldosteronoma cells from five patients with primary aldosteronism. hANP exerted a nearly identical inhibitory action on basal secretion of each of these steroids and antagonized also the stimulating effects of ACTH, serotonin, metoclopramide and vasoactive intestinal polypeptide. The results suggest that in human aldosteronoma cells hANP may be a non-selective inhibitor of corticosteroid biosynthesis and that the site of inhibition of steroidogenesis may be localized to the early pathway of steroid biosynthesis.

Adenoma↗
PubMed1988

Glycosaminoglycan containing fat-storing cells in hepatic fibrogenesis.

Male F-344 rats were treated for 10 weeks either with CCl4 (0.2 ml/kg, per os, twice a week) or with CCl4 (same as above) and phenobarbital (0.2 g/l in drinking water). Liver fibrosis and cirrhosis developed in both treated groups, and was confirmed histologically. Cirrhosis was more frequent after the CCl4 + phenobarbital treatment. The collagen content of the liver, measured by morphometry and biochemically, was significantly higher in the animals of the group treated with CCl4 + phenobarbital than in the animals treated only with CCl4. Specially altered fat-storing cells (Ito cells) were found in the periportal and septal fibrotic areas in direct proportion to the amount of fibrosis and cirrhosis. They were identified as altered fat-storing cells by their desmin content and Vitamin A storing capability. This study demonstrated that these cells were enlarged and contained neutral fat, lipofuscin and PAS-positive material. The potential role of GAG-containing FSC in fibrogenesis is discussed.

Animals↗
PubMed1988

Life expectancy in chronic liver disease.

Life-table analysis is a suitable method for evaluating the effectiveness of therapeutical approaches to and the progression of, chronic diseases. The authors performed 324 liver biopsies in patients with liver disease between 1976 and 1986. The cumulative life-table analysis of Cutler and Ederer was applied in this retrospective study. Survival rates of different groups of patients expressed as the 7-year life expectancy were as follows: toxic hepatitis 90%, steatosis hepatitis 87%, chronic persistent hepatitis 87%, nonspecific reactive hepatitis 76%, chronic active hepatitis 72%, acute alcoholic hepatitis 66%, liver cirrhosis 40%. There seems to be a correlation between the severity of histological alteration and live expectancy. A similar correlation between the inflammatory cell infiltration and life expectancy cannot be observed. The life expectancy of patients with chronic active hepatitis has significantly improved recently. Further improvement of survival of patients with liver cirrhosis can be expected only from a reduction of alcohol consumption. The results can be regarded as a reference data for life expectancy of patients with chronic liver disease in Hungary.

Biopsy↗
PubMed1987

Immunohistochemical localization of atrial natriuretic peptide in primary aldosteronism.

Using the immunoperoxidase method with specific antibody, we examined the presence of atrial natriuretic peptide (ANP) in adrenal tissues of a patient with primary aldosteronism and those derived from a patient with Cushing's syndrome. We found cells immunopositive for ANP in primary aldosteronism but not in Cushing's syndrome. In primary aldosteronism, we noted positively stained cells mainly but not exclusively in the adenomatous tissue. These results demonstrate for the first time the presence of immunoreactive ANP in adrenal tissues of a patient with primary aldosteronism and suggest that adrenal ANP may have potentially important impacts on aldosterone secretion in this disorder.

Adrenal Glands↗
PubMed1987

Cytomembranous inclusions observed in acquired immunodeficiency syndrome. Clinical and experimental review.

Two types of cytomembranous inclusions commonly occur in patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related conditions: tubuloreticular inclusions (TRI) and cylindrical confronting cisternae (CCC). CLinical and experimental studies both indicate that the occurrence of TRI in AIDS, systemic lupus erythematosus, or viral infections is directly related to endogenous systemic or local elevations of type I interferons (interferons alpha or beta). Moreover, these inclusions develop in patients or rhesus monkeys undergoing interferon alpha treatment. Rarely had CCC been reported in human tissue before the AIDS epidemic, but they were well known to develop in the hepatocytes of chimpanzees after experimental inoculation with human non-A, non-B hepatitis agent. In AIDS, CCC frequently coexist with TRI, and their appearance is associated with disease progression. A relationship of CCC to type I interferons is indicated by recent in vitro investigations, but clinical discordances in their appearance of TRI, and CCC suggest some differences in their pathogenesis, possibly related to cellular susceptibility or etiologic cofactors.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Morphology and immunohistochemistry of experimental and human non-A, non-B hepatitis.

The diagnosis of non-A, non-B hepatitis (NANBH) presently depends on the exclusion of hepatitis A, B and other causes of hepatitis, because no specific tests are available for diagnosis. Different approaches were used in order to detect NANBH infection in human and chimpanzee tissue. Endogenous interferon production was not detected in the weekly serum samples of 6 chimpanzees inoculated with a human agent of NANBH in contrast to the 5 HBV-infected animals. An antibody raised against a glycoprotein (GP77) associated with NANBH reacted immunohistochemically with liver biopsies obtained from NANBH-infected chimpanzees and with 11 out of 14 human liver biopsies from patients with NANBH. Two out of 12 human biopsies taken from patients with other liver diseases were positive. Diffuse reaction was noted in the cytoplasm of hepatocytes in chimpanzees. Three reaction patterns--diffuse, submembranous and perinuclear--were observed in human liver biopsies. A 35S radiolabeled DNA-probe of 780 base pairs--specific activity 5.4 x 10(4) cmp/micrograms DNA--isolated from NANBH-infected chimpanzees has been shown to hybridize in situ with liver sections from NANBH-infected chimpanzees. Data suggest that immunohistochemical and in situ hybridization methods can be successfully used for detection of NANBH infection in the liver of humans and chimpanzees.

Animals↗
PubMed1986

[Hepatoblastoma].

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Carcinoma, Hepatocellular↗
PubMed1986

Experimental studies on the effect of hepatoprotective compounds.

The hepatopharmacological actions of Prostacyclin, 1-phosphate-4-amino 5-carboxamido-imidazole (AICA-P), Catergen, Silymarin and a thiazolidine compound were investigated by applications in in vitro and in vivo model systems. The usefulness of the in vitro system to screen for potential hepatoprotective agents and to investigate the molecular mechanism of these substances is shown. It was concluded that different patterns of hepatoprotective action were elaborated by the same drug depending on the model system used for testing. PGI2 and the thiazolidine compound showed remarkable protection in acute liver damage. However PGI2 circumvented only the CCl4 induced cellular injury, and was inactive in the galactosamine model system. The induction of cirrhosis could be modified by the simultaneous treatment with PGI2 or by the thiazolidine compound but the fully developed cirrhosis was not affected. On the contrary AICA-P and Silymarin treatment resulted in reduction of the amount of collagen in cirrhotic liver.

Aminoimidazole Carboxamide↗