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Biomedical subjects

Z Szentirmay

Publications and source records attributed to Z Szentirmay.

At least 19 recordsLinked to original sources

[The use of multivariate mathematical methods in medical diagnostic systems--a model for the evaluation of cytological smears].

The methods of the multivariate mathematics have been applied in several studies to increase the diagnostic reliability of medical decision support system. In the recent years some new algorithms for decision support (fuzzy logic) and for pattern recognition (neural nets), both specified by nonlinearity, were developed. This paper provides results for the application of this methods in the area of quantitative cytology and the comparison with the traditional classifiers. 21 normal, 15 dysplastic, 23 malignant, Feulgen stained gastric imprint smears were analysed on a Leitz Miamed DNA equipment. The determination of mean DNA content, the 2c deviation index (2cDI), 5c Exceeding rate (RcER), G1,S,G2 phase fraction ratios, cell nucleus area, form factor was performed. The discriminant analysis classified correctly the 95.6% of malignant cases, 86.7% of dysplasias, and 80.7% normal cases. Our diagnostic system using fuzzy logic made the diagnostic borders fine tuneable, and reliable. The back propagation neural net could classify all three diagnostic groups above 95% correctly. The application of nonlinear computational methods made the diagnostic system more reliable. The application of these algorithms are encouraged.

Algorithms

[Clinical pathology of gastric mucosal dysplasia].

The stomach cancer develops on dysplastic lesions of gastric mucosa. It can be found in every precancerous condition, as chronic gastritis, gastric adenoma, giant rugal hypertrophy, chronic peptic ulcer, gastric stump after partial resection, pernicious anaemia. So, this dysplastic change is not a specific lesion. Different classifications are known for grading of gastric dysplasia. Authors evaluated them compared with each other. The signs of dysplasia were studied in 306 gastric aimed biopsy specimens from 233 patients between 1979-1990. In this material severe dysplasia occurred in 20.6%. It means a frequency of 0.84% regarding all gastric endoscopies in the same period of time. The endoscopic investigation revealed a protruded lesion in 18.5% and excavated one in 45.9%. What is very important, local change could not be detected in 35.6%. Follow-up study could be performed in 49 patients in a period of 1-7 years. In this group cancer developed in five patients. By the other hand, 22 gastric carcinomas were proved amongst 233 patients. The authors' recommendation is to follow-up the patients bearing gastric dysplasia at least during 10 years after the diagnosis.

Diagnosis, Differential

[Diagnostic possibilities of endoscopic ultrasonography in the detection of gastric cancer].

After conventional gastroscopy and biopsy the endoscopic ultrasonography (EUS) was performed in 115 patients with gastric ulcer and carcinoma. The markers of benignity and malignity were analyzed by EUS, and the criteria of benign and malign excavated lesions were described. On the base of endoscopic pictures 3 groups of gastric excavations were distinguished, and the recorded images of this excavations were reevaluated. Benign ultrasonic markers were detected in one case of excavated tumors, in 54% in group of ulcers with suspicion of malignity and in 82% in cases of benign ulcers. Authors evaluate the cause of overestimate. Ten cases of early gastric cancers are reported. Authors believe that the endosonographic examinations of the stomach are valuable in detecting and stating of gastric carcinoma.

Diagnosis, Differential

[Cellular DNA determination and its significance in the identification of tumor recurrences, metastases and second primary tumors].

The DNA content of 30 malignant tumors and their metastases were compared. The DNA indices of tumors (expressed by the mean DNA content of G0.1-phase tumor cells and leukocytes) differ from each other, but in metastases they are almost the same with the values of primary tumors. It can also be observed, if a tumor consisted of more than one subpopulation of tumor cells, the metastatic potential of clones can be different. However, there is no significant relationship between the degree of ploidy and the occurrence of metastasis. The stability of DNA index in tumors and their metastases were used to distinguish two primary tumors even if their histological patterns were very similar. We present an example of the above mentioned phenomena in which the results of DNA analysis is supported by the results of mucin histochemistry and the follow up data.

DNA, Neoplasm

Determination of G1-S-G2 phase fraction ratios of tumour subpopulations from DNA histograms.

Authors describe a new mathematical approach based on mixture decomposition and maximum likelihood method for the determination of subpopulations and G1-S-G2 phase fraction ratios in aneuploid, multiploid DNA histograms. A special computer routine was developed for this purpose (DAHSY). The present study relates to DNA histograms obtained by a Leitz Miamed DNA TV image analyser system. Altogether 23 normal, 14 dysplastic and 28 tumours Feulgen stained gastric imprint smears were measured. In addition to determination of subpopulations and G1-S-G2 phase fraction ratios, the authors also performed a morphometric analysis of Feulgen stained nuclei and determined the values of 5c exceeding rate (5cER) and the 2c deviation index (2cDI). More than one subpopulation were found only in tumours. The usual G1-S-G2 phase fraction rates in normal gastric smears were 85.5%, 9.04%, 4.9%, in dysplastic cases 74%, 15.4%, 10.2% and in tumours 53.8%, 22.9%, 18.8%. Significance of the differences were calculated by the T-test. The G1 phase fraction ratio clearly discriminates the malignant lesions from all others. The S+G2 phase fraction ratio, however, distinguishes the normal cases from the dysplastic ones. The 2cDi and 5cEr could support a multivariate diagnostic system. The cell nucleus area was found also to be of diagnostic value.

Algorithms

DNASK--a new image analysis module for TV image cytometry.

The DNASK is a PC-based image analysis module for quantitative cytological and histological examinations on Feulgen-Schiff preparations. The module consists of a frame grabber, a CCD black and white video camera and the DNASK software package which can be incorporated in an IBM compatible PC-AT joining to a standard pathological research photo microscope. The use of 386 IBM AT systems leads to significant decrease of the measurement's time. Mono- or color VGA graphics card should be used. The resolution of the images is 512 x 512 pixels and 256 gray values. The image caption is made in less than 0.5 second, the measurement of a cell nuclei (18 parameters) takes less, than 5 seconds (IBM AT 286). The camera is a standard CCD one. The microscope should be a good quality, modern microscope with built-in light source, however, the application of voltage stabiliser is strongly recommended. The software is able to measure the parameters mostly used and suggested in the international literature: 15 morpho- and densitometric parameters of the cell nuclei 6 DNA histogram parameters of the measured case, like DNA Index, 2c deviation Index, 5c exceeding rate, G1-S-G2 phase fraction ratio. The system supports the grouping of the measured cases and at the end of a study results of the single measurements can be collected and summarized in an ASCII file, which is readable by major statistical programpackages. The DNASK has a special graphical user interface for the control of the program.

Algorithms

Early gastric cancer induced by N-ethyl-N'-nitro-N-nitrosoguanidine in a cynomolgus monkey six years after initial diagnosis of the lesion.

A signet ring cell carcinoma in the gastric antrum of a Cynomolgus monkey induced by N-ethyl-N'-nitro-N-nitrosoguanidine was sequentially studied by endoscopy, biopsy, and autopsy. The carcinoma was first detected on the angulus of the stomach at the 38th month as a slightly elevated lesion. Sixty-one months later this tumor was found to be still in the "early" (intramucosal) stage. Another, independent, initial gastric cancer was also discovered. This is the first example of an induced gastric carcinoma remaining in the "early" stage during a six-year follow-up period after the initial histologic diagnosis.

Adenocarcinoma, Mucinous

Geno- and phenotypic characterization of the de novo arising colon carcinoma in familial polyposis coli.

De novo origin of colon carcinomas has been demonstrated in a case of familial polyposis. Independent origin of the polyps and the synchronous carcinomas was confirmed by their different pheno- and genotypes. Characterization of the phenotype was based on the mucin profile of the polyps and the synchronous carcinoma. The phenotype of each polyp was different and represented either duodenal, colonic or embryonal type of differentiation. The phenotype of carcinoma proved to be adult colonic type. The DNA content of the polyps and carcinoma has been evaluated by cytophotometry. The multiclonal origin of each polyps and synchronous carcinomas has been supported by their different DNA indices. Occurrence of de novo arising carcinoma in familial polyposis calls for a frequent follow-up examination of patients with subtotal colectomy and strongly support the need for total colectomy.

Adenomatous Polyposis Coli

Demonstration by in situ hybridization of ret proto-oncogene mRNA in developing placenta during mid-term of rat gestation.

Expression of the ret proto-oncogene (proto-ret) in rat conceptus tissues during development was examined by in situ hybridization using photobiotin-labeled oligodeoxyribonucleic acid probes corresponding to regions coding for the kinase and transmembrane domains of proto-ret gene product. High levels of the proto-ret transcripts were detected in the cytotrophoblasts in the placenta in the mid-gestational period (days 10 and 11), but on day 14 of gestation, when the placenta was undergoing morphological changes, transcripts could no longer be detected in the trophoblasts. These results suggest that the increased expression of proto-ret may be associated with the proliferation and/or differentiation of trophoblast cells at a specific stage. Improvements in the in situ hybridization technique by introduction of an ultrafast microwave energy fixation method, and repeated-reaction cycling of avidin-alkaline phosphatase and a biotinylated anti-avidin antibody for signal amplification, are also briefly discussed.

Animals

Malignant fibrous histiocytoma of the mediastinum.

A case of malignant fibrous histiocytoma in the right postero-superior mediastinum in a 43-year-old male patient is presented. He was operated on and a part of the tumor including the infiltrated second segment of the lung was resected. At reoperation, the great vessels were found infiltrated by the tumor and radical exstirpation could not be carried out. The patient died 4 months after discovery of his disease due to further growth of the tumor. This case is the fifth malignant fibrous histiocytoma of the mediastinum described in the world literature.

Adult

Kinetic metabolism of vinpocetine in the rat.

The pharmacokinetics of vinpocetine (Cavinton), a new potent vasodilator, and of its main metabolite have been studied in rats by specific extraction and radio thin-layer chromatography following i.v. and p.o. administration. The drug is rapidly eliminated, its half-life was found to be 125 min. The apparent volume of distribution was 3.8 l/kg and the clearance rate 33 ml/min/kg. From the equation describing the concentration-time curve a two-compartement open model was computed. Bioavailability of vinpocetine after p.o. administration was about 50%. The main metabolite, free apovincaminic acid, is formed very rapidly in rats and is eliminated from plasma with a half-life of 360 min.

Administration, Oral

Pharmacokinetics of vinpocetine in humans.

The pharmacokinetics of ethyl-apovincaminate (vinpocetine, Cavinton), a new vincamine derivative has been studied in volunteers after p.o. and i.v. administration. The concentration of the drug was determined by mass-fragmentography in human plasma. There was a biphasic elimination of the substance after i.v. injection with a T1/2 alpha of 0.136 h and with a T1/2 beta of 4.83 h. The value of Vdss (2.1 l/kg) shows a high adsorption of the drug by tissue proteins. The clearance rate of elimination was 0.366 l/h/kg. Oral administration of the drug resulted in maximum plasma concentration 1--1.5 h after the administration with values of 20--62 ng/ml. The bioavailability of the drug--calculated from the ratio of the areas under the concentration-time curves--proved to be 56.6 +/- 8.9%. Unchanged vinpocetine could not be detected in urine. From the results two-compartment open models were constructed and the steady state concentrations after multiple dosing were computed.

Administration, Oral

Study of the antitumoral activity of S-carbamoyl-L-cysteine derivatives in animal experiments.

The antitumoral activity of three amino acid derivatives, S-carbamoyl-L-cysteine, S-ethyl-carbamoyl-L-cysteine, and S-chloroethyl-carbamoyl-L-cysteine, was studied. The ethyl and chloroethyl derivatives had a pronounced curative effect on certain animal tumors. It is interesting in the case of S-carbamoyl-L-cysteine that N-ethylization of the substance resulted in increased chemotherapeutic effectivity with no simultaneous change of the toxicity. According to various studies this effect is different in many respects from that of the known cytostatics, and a possibility of a specific selective or surface activity is raised.

Animals

Cytophotometric determination of basic proteins with heparin-alcian blue method.

For the quantitative cytochemical determination of basic proteins, Heparin-Alcian Blue (HAB-was found to be a more suitable staining procedure than the generally used alcalic Fast green reaction. HAB is able to stain all the histone fractions, but there is no staining following deamination (gelelectrophoretic examinations) and no aspecific staining (Millipore filter model). In EHRLICH ascites tumour cells, changes in the FEULGEN-DNA content is followed by the proportional changes of HAB-basic protein content. After HAB reaction, the FEULGEN reaction can be performed on the same slide.

Alcian Blue

[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

[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

[Enzymologic investigations of Vx2-carcinoma transplanted into the stomach of rabbits (author's transl)].

Suspensions of V x2-carcinoma cells were inoculated into the stomach wall of rabbits. In 26 animals, changes of lactic acid hydrogenase (total activity and isoenzyme distribution) were followed from the transplantation day to complete development of a tumor. Findings were compared with mucosa specimen taken from different parts of the stomach. As compared with control animals (injection of physiological saline solution into the stomach wall), total enzyme activity was elevated and isoenzymes showed characteristic distribution in homogenisates from tumorous tissue. Mucosa covering the tumor did not reveal such alterations of enzyme activity. It can thus be concluded that V x2 carcinoma was limited to submucosal layers and did not invade the mucosa. This conclusion was confirmed by histologic examination.

Animals