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Biomedical subjects

K Voss

Publications and source records attributed to K Voss.

16 recordsLinked to original sources
PubMed1990

Cognitive test profile analysis for the identification of dementia of the Alzheimer type.

Two measures of profile similarity have been derived that offer complementary information about the classification of patients with diagnoses of probable dementia of the Alzheimer type (DAT). These measures were obtained for 31 probable DAT patients and 31 age- and education-matched controls using a set of six newly constructed cognitive scales designed to provide reliable measurement in both patient and control groups. A measure assessing similarity to the average performance of the controls provided perfect separation of the patient and control groups. A measure assessing similarity to the average performance of the probable DAT patients identified up to four atypical cases of probable DAT. One of these four cases has come to autopsy and was found to have Pick disease. The cognitive profiles of this Pick patient and an autopsy-confirmed DAT patient are compared to illustrate the potential advantages of using DAT patients as the reference group for profile analysis.

Aged↗
PubMed1989

In vitro and in vivo effects of sodium selenite on 7,12-dimethylbenz[a]anthracene--DNA adduct formation in isolated rat mammary epithelial cells.

Supplementation with increasing quantities of selenium (Se), as sodium selenite, to cultures of rat mammary epithelial cells resulted in a proportional depression in 7,12-dimethylbenz[a]anthracene (DMBA) binding to DNA. A depression in the two major anti bay-region dihydrodiol epoxide-deoxyribonucleoside adducts largely accounted for the reduced binding. DMBA-DNA binding in freshly isolated mammary cells from rats fed a diet containing 2.0 p.p.m. Se and incubated in culture with DMBA for 24 h was decreased 32% compared to binding in cells obtained from rats fed 0.1 p.p.m. Se. DMBA-DNA binding in mammary cells obtained from rats fed supplemental Se for 2 weeks or more was depressed compared to that occurring in cells from unsupplemented rats. The reduced ability of cells obtained from rats previously fed a 2.0 p.p.m. Se diet to activate DMBA to intermediates capable of binding to DNA became increasingly apparent with the duration of exposure to the carcinogen. Consistent with the in vitro supplementation study, cells isolated from rats previously fed a diet containing 2.0 p.p.m. Se had a reduced occurrence of the two major anti dihydrodiol epoxide adducts. The depression in DMBA binding following selenite supplementation, both in vitro and in vivo, supports the ability of Se to inhibit the initiation phase of carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1989

[PARTICLE--an expert system for microscopic image analysis].

The pathologist is usually not an expert in engineering or image analysis. Therefore an expert system was developed, entitled PARTICLE, to help pathologists producing image analysis programs in histological pathology. The PARTICLE expert system is based on karyometric data using the AMBA/R dialogue and programming system.

Expert Systems↗
PubMed1986

[2D-histograms of the nucleus area and nucleus shape in the diagnosis of astrocytomas and glioblastomas].

8 astrocytomas grade 1-4 and 2 glioblastomas were investigated by a system of automated microscope picture analysis. Histograms of nuclear area and shape from more than 1,000 measured nuclei per tumor were analysed. Both one- and two-dimensional histograms show findings which correlate with the malignant potential of the gliomas. The nuclear area rises with increasing tumor malignancy. On the other hand the measurements of nuclear shape factor are inversely related to the level of malignancy, indicating substantial irregularities in the nuclear structure. The 2D-histograms of both measured parameters also show changes which are correlated with the grade of tumor malignancy and which can be described as shift, loss of compactness and enlargement. The histogram method is discussed as an objectifiable process characterizing important cell and nuclear attributes connected with tumor malignancy. Histograms of both, nuclear area and shape can be helpful in the classification and grading of astrocytomas and glioblastomas.

Adult↗
PubMed1986

[Morphometric analysis of fibrocystic breast disease].

We used the automated microscopic image analysis (system "Robotron A 6471"; software AMBA/R) to study the ductal epithelium in biopsies from 88 patients with fibrocystic breast disease, including 52 with proliferative mastopathy. Significant differences were demonstrated using reproducible data and selective caryo- and histometric parameters which allowed the separation of ductal hyperplasia and ductal cell proliferation with atypia. In addition, multiparameter analysis indicated that cases with proliferative mastopathy III can be separated into two groups which have probably a different high risk with respect to carcinoma.

Adult↗
PubMed1979

Image processing in pathology. IX. A new morphometry system and its application on gangliocytes of the nucleus olivaris.

This paper describes a new software system for automatic image processing in pathology. The system is based on the hardware NU2/ODD/PDP8 and the thereby yielded results. The effectiveness of the system esp. its velocity has been essentially improved by a significant modification of the primary data sampling and by the new implementation of feature determination. The first application of this new system concerns age-dependent alterations of the gangliocytes in the nucleus olivaris.

Adolescent↗
PubMed1979

[Comparative, quantitative and morphological investigations (automatic image analysis--micromorphometric analysis) of myocardium of rat isoprenalin treatment (author's transl)].

The alterations of areas of myocardium of male rats (2, 4, and 6 months) are investigated after isoprenalin treatment (0.05 mg/kg body weight and day i.p. for 30 days). The investigations are carried out using automatic microscope picture analysis, morphometric point counting and resp. Both methods yield the same qualitative results: The effect of isoprenalin is dependent on age and yields for old rats (6 months) only very little morphometric alterations in the myocardium. The automatic microscope picture analysis is a very effective method of investigation (45 seconds/cross section).

Age Factors↗
PubMed1979

[Classification of nerve cell forms in lamina IV of the visual cortex of albino rats using Nissel preparation with the help of automatic picture processing].

1) Using the automatical picture processing device "MORPHOQUANT", VEB Carl Zeiss Jena, layer IV of the adult albino rat's area 17 was investigated in Nissl-preparations to classify pyramidal and stellate cells on the basis of quantitative features. 2) A review is given about the applied computer programme. 3) 30 seconds are necessary for adjustment, measurement and statistical calculation. 4) Five features per neuron soma were registered and statistical calculated: neuron area in picture points (KOFL), mean value of extinction (EXTM), total extinction (EXTS), shape (i.e. dia ratio, DMVH), and the distribution of strong coloured particles (i.e. centricity, ZNTR). 5) High statistical significance could be achieved only with regard to the neuron area and the distribution of strong coloured particles. 6) The causes for different results obtained in previous and present measurements and the importance of differentiation between several types of neurones are discussed as well.

Animals↗
PubMed1979

[Cytomorphometry of area 17 of the albino rat using the automatic picture processing].

Using the automatical picture processing, the layers II to IV of the adult albino-rat's area 17 were investigated in Nisselpreparations. Within 15 hours 14 features from approximately 10 000 neurons could be registered. Five features (neuron density = neuron number per 10 areas of measurement, mean value of neuron area in picture points, mean value of mean extinctions of neurons, whole extinctions of neurons, mean value of relative granula area of neurons) were statistically calculated and considered under several aspects: 1st Concerning the specifity of the layers very exact results could be obtained. 2nd In a detailed investigation of the lamina V pyramidal cells estimating somata areas no statistically significant classification could be achieved. 3rd There are slight structural changes of area 17 in rostrocaudal direction, but without statistical significance. Further investigations are necessary. 4th It is possible to differentiate between pyramidal cells and stellate cells of lamina IV. The numerical proportion between these two types of cells, however, deviates from individual estimations. Until now, this problem could not be satisfactorily be solved.

Animals↗
PubMed1978

Image processing in pathology.

The present study is an effort to ally biopsies to well defined groups of diseases by means of automatic analysis of liver cell nuclei. The results obtained should support the morphologic differential diagnosis of liver diseases. A total of 78 liver biopsies from patients with obstructive jaundice, chronic hepatitis, acute viral hepatitis or with alcoholic liver injury were investigated. Performing automatic analysis of the microscopic pictures 95% of the equatorial sectioned liver cell nuclei are correctly recognized.

Cell Nucleus↗
PubMed1978

Image processing in pathology. IV. Internal structure of mitochondria.

For extensive recording of mitochondrial membrane lengths hitherto statistical methods were applied which only provide mean values. Conventional measurements of the lengths by means of curvimetry or by intersection counts are required for estimating size distributions and secondary parameters. The former method requires expenditure in time, the latter yields only very rough values for single organelles. Automatic image processing is a possible way to obtain more informations. A method for an automatic definition of the internal mitochondria structure is given in this paper and preliminary results are discussed.

Computers↗
PubMed1978

Image processing in pathology. V. Interpretation of feature distributions of liver cell nuclei in histological sections.

A new method is applied for calculating the volume and extinction of liver cell nuclei from area and extinction of their sections in histological slices. With a special classificator for the automatical processing of microscopical pictures 96 per cent of morphologically controlled aequatorial sections of liver cell nuclei are correctly recognized. Using a mathematical model (additive fitting of three normal distributions to the given feature distribution) ploidie classes and volume classes can be recorded more exactly.

Cell Nucleus↗
PubMed1978

[Experimental investigations on the regeneration of aortic endothelial cells. Automatic and visual evaluation of autoradiograms (author's transl)].

Autoradiographic studies on plane preparations using 3H-thymidine and pulse cytophotometric investigations on scrape preparations of aortic endothelium from 34 rabbits have brought the following results: By means of multiple 3H-thymidine-injections the number of labelled endothelial cells is higher in young growing animals than in older rabbits; pulse cytophotometrically we did not find any indication of polyploidization processes; from that we conclude a decrease of the growth fraction with advancing age. In comparison to visual counting the automatic image analysis is a highly effective method for the evaluation of autoradiograms. After multiple 3H-thymidine applications the mean blacking intensity of the labelled cell nuclei is lower in 2 months old animals than in 12 months old rabbits; that may mean an increase in the S-phase duration of the proliferating endothelial cells of the older animals. In the area with branching sites there are more 3H-thymidine-labelled endothelial cells than in the neighbouring vascular segments. The significance of these findings for the preferential incidence of arteriosclerosis in this area is discussed.

Age Factors↗
PubMed1977

[Image processing in pathology. III. Structure and use of an automatic morphometry system for recording morphometric features of nuclei (author's transl)].

UNLABELLED: An image processing system for morphological investigation of liver cell nuclei in biopsy specimens is demonstrated. The present study deals with the age dependence of normal hepatic nuclear areas. The results were compared with those of conventional methods. MATERIAL AND METHODS: The image processing system consists of a microscope, an image dissector and a computer (central processing unit, display, teletype, magnetic tape devices and line printer). 74 liver biopsies were investigated. They sshowed no signs of acute or chronic diseases. Paraffin sections of 4 micron in thickness were prepared and stained by Feulgen method. 8-10 biopsies were available for each decade from 1-8. 18,000 liver cell nuclei from all specimens were isolated and measured automatically. Using the image processing system and adequate computer programs 20 parameters of all isolated nuclei were gained (parameters of shape, size and structure of the nuclei). For sampling and processing of the information the following programs are developed: PROBE Program for investigation of optimal parameters of scanning and processing. SAMPL Program for scanning, object isolation, feature extraction and storage of data records. KORRL Program for investigation of correlations between the features of objects. LISTE Program for listing of data records. ULTRA Program for search of objects with extremal features. CODER Program for correction od data records. ADAPT Program for training of classificators. SCHAU Program for demonstration and checking of the classificator. MORPH Program for output of feature distributions and statistical parameters. Following object features were calculated and investigated: features of size: KOFL area within the object contour; KKFL minimal covex area of the object; ZKFL object area without holes; KONL length of the object contour.

Adolescent↗
PubMedDate not supplied

[Image processing in pathology. IV. Age dependent changes of morphometric features of liver cell nuclei in biopsies].

PROBLEM: Several authors reported age dependent changes of single morphometric parameters on liver cell nuclei. In this study a recently developed automatic morphometry system was applied to recording of many liver cell nuclei parameters in histologic sections of liver biopsies simultaneously. The relations of the automatically generated parameters according to the age of the individuals are to be demonstrated.

Adolescent↗