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Biomedical subjects

B Molnár

Publications and source records attributed to B Molnár.

16 recordsLinked to original sources
PubMed1992

[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↗
PubMed1992

[Quantitative morpho- and densitometric parameters in the evaluation of aspiration cytology smears of the breast].

Quantitative morpho- and densitometric analysis of Feulgen stained breast aspiration smears were performed by absorption cytophotometer and a TV image analyser. The DNA Index, and the ratio of G1-S-G2 phase fraction ratio yielded by the quantitative DNA analysis, showed significant differences between benign and malignant alterations. Based on the 13 morphometric and 5 densitometric parameters the TV-image analyser could classify the examined smears 80% correctly by cluster analysis. Groups of the cytological Grade I.-III. were also differentiable by this method. The application of TV image analyser system in the diagnosis of aspiration cytological smears could be suggested. The complex quantitative morpho- and densitometric analysis could contribute to the correct classification of diploid tumours.

Biopsy, Needle↗
PubMed1992

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↗
PubMed1992

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↗
PubMed1991

Effect of Paxirasol aerosol on the clinical condition and objective functional respiratory parameters of obstructive respiratory tract disease patients.

Paxirasol aerosol applied in daily 3 x 5-puff doses was well tolerated by the examined patients. In the course of the 21-day therapy the laboratory findings did not change-haemopoetic or liver injury was not observed. On two-thirds of the patients the amount of sputum decreased in response to Paxirasol aerosol but the symptoms accompanying expectoration did not change notably. Among the objective respiratory parameters FEV1 values increased and Rtot values decreased. These changes may be observed during the first third of therapy. There was a continuous and linear increase in FEV values characteristic of respiratory pressure conditions. This phenomenon is not characteristic alone of the changes of values of obstructive diseases patients. The authors recommend the use of Paxirasol aerosol for the treatment of respiratory tract disease patients.

Administration, Inhalation↗
PubMed1990

DNA distribution pattern and comparison of quantitative data in breast tumours.

Aspiration cytology smears from 24 breast alterations were subjected to cytophotometry and TV image analysis. The smears were grouped according to histological diagnosis and cytological pattern. Cell cycle parameters and DNA indices were calculated from the decomposition of the DNA histograms. Based on quantitative morphometric features the TV image analyser distinguished the benign cells from the malignant ones. In benign cases its diagnostic accuracy is of 80%. Cytological Grades 1, 2 and 3 are also identifiable by this system. Cytophotometric measurements were also performed with 22 invasive breast cancers with known 5-year survival. The cell cycle parameters were related to the survival data. From the point of view of survival only the ratio of the S plus G2 phase cells of all the parameters examined proved to be significant.

Adenofibroma↗
PubMed1990

[DNA cytometry and morphometry, based on TV image analysis, in the diagnosis of gastric carcinoma].

Cytological smears from gastric biopsies were studied by two types of TAS. Böcking's algorithm and a great number of form factors were used to separate the intact cells from the tumourous ones. The numerically expressed density features and morphometric parameters are able to indicate the possibility of malignant transformation even in dysplasia. These values become much higher in tumours and lead to unequivocal diagnosis. Both types of TAS render valuable help in assessing cases not reliably diagnosed by routine staining procedures.

Biopsy↗
PubMed1989

Endocervical cytology: characterization of the cells by image analyzer.

Authors report on 359 patient's endocervical smears taken by cytobrush. Stromby's endocervical brush did not cause bleeding disturbance or preventing colposcopic examination. The smears contained numerous, well evaluable squamous and endocervical cells. Out of seven cytologically positive cases three proved to be negative by colposcopy. Histology, however, confirmed the cytological diagnosis. Cytology was followed by histology in 42 cases. Cytological and histological diagnoses were compared, there was one false negative. For the more precise characterization of endocervical cells 13 features were measured by a Robotron type image analyzer and the results were statistically analyzed. The respective cell groups can be separated from each other by morphometric and densitometric parameters. Results of this study have produced a data base that can be extended further on. It may give help in case of differential diagnostic problems since it is capable of distinguishing certain cell groups, consequently these data can be incorporated into a diagnostic program.

Cervix Uteri↗
PubMed1988

Fibronectin determination in pregnancy.

The levels of fibronectin were determined by immunoturbidimetric assay in two populations: (a) plasma of healthy nonpregnant and pregnant women, and in amniotic fluid of healthy pregnant females; (b) plasma of umbilical cord blood of healthy newborns and of newborns with sepsis. Fibronectin concentrations of amniotic fluid showed a significant decrease during pregnancy, but the changes of plasma fibronectin levels were not significant in this period. In newborn sepsis, the levels of plasma fibronectin were significantly decreased. We did not find a significant difference between the fibronectin concentration of umbilical cord blood of premature infants compared to mature infants.

Adolescent↗
PubMedDate not supplied

Effect of colchicine and prednisolone upon the peptidergic neurosecretory product in Cyprinus carpio L.

After a treatment with physiological doses of colchicine and prednisolone, the rapid transport of the neurosecretory granules in the preoptico-neurohypophyseal tract of Cyprinus carpio L. is blocked. This fact is manifested by the accumulation of neurosecretory granules and of Hering's bodies at the level of fibres of preoptico-neurohypophyseal tract, and on the contrary, by the significant reduction of neurosecretory product in the nerve fibres of the neurohypophysis. The neurotubules which participate in the rapid axonal flux of neurosecretory granules do not suffer detectable ultrastructural changes.

Animals↗
PubMedDate not supplied

DNA cytometry and morphometry by TV based image analysis system (TAS) in the diagnosis of gastric carcinoma.

Cytological smears from gastric biopsies were studied by two types of TAS. Böcking's algorithm and a great number of form factors were used to separate the intact cells from the tumourous ones. The numerically expressed density features and morphometric parameters are able to indicate the possibility of malignant transformation even in dysplasia. These values become much higher in tumours and lead to unequivocal diagnosis. Both types of TAS render valuable help in assessing cases not reliably diagnosed by routine staining procedures.

Carcinoma↗