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H Barz

Publications and source records attributed to H Barz.

15 recordsLinked to original sources
PubMed1992

[The effect of arteriosclerosis on the wall elasticity of the human common carotid artery].

The arterial distensibility and the modulus of volume elasticity of more than 100 isolated human carotid arteries was measured and correlated with arteriosclerosis and aging. The loss of arterial distensibility progresses steadily with aging. Arteries with severe arteriosclerosis and arteries with minimal arteriosclerosis show almost similar distensibility. On the other side the differences between distensibility of arteries with moderate arteriosclerosis and arteries with minimal as well as severe arteriosclerosis, especially in the younger and middle ages, are significant.

Aging↗
PubMed1991

Diminished synaptosomal dopamine (DA) release and DA autoreceptor supersensitivity in schizophrenia.

Post-mortem brain regions of schizophrenics were investigated in comparison to matched controls regarding synaptosomal K(+)-stimulated [3H]DA release and its modulation by DA autoreceptors. Brain specimens were cryopreserved in liquid nitrogen until release experiments; synaptosomes from brain pieces preincubated with dimethylsulfoxide have unchanged ability for [3H]DA release and its autoreceptor-mediated inhibition after cryo-preservation. Release data were individually corrected for post-mortem delay back to the zero-time state based on [3H]DA release alterations after in situ preservation of rat heads. In schizophrenia, the K(+)-stimulated [3H]DA release from superfused synaptosomes of the nucleus (n.) accumbens and n. caudatus was diminished significantly. Furthermore, functional supersensitivity of the modulatory DA autoreceptors could be demonstrated in these regions. The alterations demonstrated seem not to be due primarily to medication since in neuroleptic-free patients similar changes were shown.

Amygdala↗
PubMed1991

Inhibition of acetylcholinesterase activity in human brain tissue and erythrocytes by galanthamine, physostigmine and tacrine.

Galanthamine, physostigmine and 9-amino-1,2,3,4-tetrahydroacridine (tacrine) were evaluated as inhibitors of human acetylcholinesterase activity from samples of postmortem human brain, fresh brain cortex biopsies and human erythrocytes. Acetylcholinesterase activity was most effectively inhibited in all tissues by physostigmine, followed by tacrine and galanthamine. The respective inhibitor concentrations exerting a half maximal effect (IC50) on acetylcholinesterase in postmortem human brain frontal cortex were 14 nmol/l, 1.0 mumol/l and 3.2 mumol/l versus 15 nmol/l, 1.1 mumol/l and 2.8 mumol/l in the hippocampus region. In addition, the inhibition of acetylcholinesterase by galanthamine was similar in postmortem brain and brain cortical biopsies from patients submitted to brain-tumour removal, indicating that postmortem changes up to 28 h after death probably did not influence the measurement of acetylcholinesterase inhibition. While physostigmine and tacrine acted equally on acetylcholinesterase from different sources, galanthamine was 10-fold less potent in inhibiting the enzyme activity from human brain that from human erythrocytes. Comparison with issues from mice revealed that galanthamine was selectively more potent in suppressing acetylcholinesterase in human erythrocytes. The results are discussed in the light of pharmacokinetic data, and conclusions are drawn for further clinical studies.

Acetylcholinesterase↗
PubMed1986

[Importance of immunohistochemistry for neuro-oncology. II. Localization of factor VIII-associated proteins and glial fibrillary acidic protein (GFAP) in angiomatous and sarcomatous tumors].

Immunhistochemical methods utilizing specific antibodies against Factor VIII-related antigen and glial fibrillary acidic protein were employed in studies of 48 intracranial and intraspinal tumors. Factor VIII-related antigen occurred only in endothelial cells of the vascular wall and is therefore not of importance for the differential diagnosis of CNS tumors. Isolated Factor VIII positive cells in the stroma of hemangioblastomas turned out to be mast cells which may also normally contain this substance. The GFAP positive cells in hemangioblastomas are believed to all be of astrocytic lineage. Many of the multinuclear giant cells present in monstrocellular sarcomas contained GFAP but were Factor VIII negative. Genuine fibroxanthoma of the meninges can apparently exist next to pleomorphic xanthoastrocytomas. As demonstrated by one of our cases, the demonstration of GFAP alone can successfully distinguish between them.

Antibodies, Neoplasm↗
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↗
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↗
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↗
PubMed1977

[The prevalence of single and synchronous multiple tumours in autopsy series and its dependence on age (author's transl)].

The present study reports the age specific prevalence rate of tumors in autopsies of the years 1958--1969, registered in the Medical Academy "Carl Gustav Carus" Dresden. The results refer to the total of all malignant tumors, to several tumor sites as well as to multiple simultaneous tumors. In many neoplasms highest prevalence occurs in presenile age (malignancies of lung, uterus, ovar, brain, and bone marrow). On the other side prevalence of carcinoma of breast, urinary bladder, kidney, prostate, and large intestine increases up to the oldest age-groups. With respect to the population the prevalence of cancer increases permanently up to the age of eighty and decreases only in the following age-groups. The age-specific prevalence of simultaneous multiple tumors referred to cases of single tumors in the post-mortem findings reveals an analogous age distribution curve. The prevalence of simultaneous cancer is discussed concerning the influence of age and duration of the malignancy.

Adolescent↗
PubMed1976

[Amyotrophic lateral sclerosis with myoclonic bodies (Lafora bodies) (author's transl)].

In the present investigation 2 sporadic cases of amyotrophic lateral sclerosis with the occurrence of myoclonic bodies (Lafora bodies) in the CNS are reported. The patients died after about 14 respectively 8 months lasting disease at the age of 41 and 43, respectively under the clinical signs of an ALS. Morphology, staining qualities, and the distribution of the myoclonic bodies in our cases correspond to the adult form of the myoclonic body disease (type Lundborg). In the literature we found further 6 cases of neurogenic muscle atrophy with the occurrence of myoclonic bodies in the CNS so that one might suppose a syntropy of these two affections. The possible pathophysiological relations of neurogenic muscle atrophy to the occurrence of myoclonic body disease in adults are briefly discussed.

Adult↗
PubMed1975

[Liver-damaging action of halothane--an animal experiment study].

After long-term exhibition to halothane (up to 96 hours), centrolobular hepatic damage (fatty degeneration, necrobiosis and necrosis) developed in rats, proportionally to the number of anesthesias and shortening of the intervals. From these results no hepatotoxic effect of halothane can be derived, since the alterations might be caused by hypoxia alone.

Animals↗
PubMed1975

[Pathological findings in subacute necrotizing encephalomyelopathy (Leigh's disease) (author's transl)].

About 8-years old boy with a brief clinical history and postmortem findings of a subactue encephalomyelopathy (Leigh-Syndrom) is reported. Pathohistological features were found to be of microcyst formation, vascular proliferation, proliferation of astrocytes, fibrillary gliosis, partial destruction of the myelin sheaths, relative preservation of the cell bodies of neurons. The lesions were symmetrical and involved the tegmentum mesencephali, the lamine quadrigemina, the substantia nigra, the tegmentum pontis, the tegmentum of the medulla oblongata, the basal protion of nucl. lentiformis, the ansa lenticularis, the thalamus, the hypothalamus and the gray matter of the spinal cord. Moderate changes were in the cerebellum. There was no marked histological changes in the cerebral cortex and white matter of the cerebrum, the mammillary bodies, the nervi and tracti optici and the peripheral nerves.

Autopsy↗
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↗