Search PubMed⌕ Search

Biomedical subjects

G Bartsch

Publications and source records attributed to G Bartsch.

At least 325 records · Page 18Linked to original sources
PubMed1979

Quantification of human sperm morphology and motility by means of semi-automatic image analysis systems.

Sperm morphology and motility are determined using a semi-automatic image analysis system under opto-manual control. The system consists of a microscope equipped with a drawing-tube, a digitizer-tablet, and a cursor interfaced to a small microcomputer. A light-emitting diode is mounted on the cursor, visible as a bright red pilot-light in the microscopic field. Sperm head and midpiece as well as the pathway of motile spermatozoa are traced with the cursor's red pilot light. The microcomputer calculates area, circumference, and length simultaneously. Motility and sperm density are determined altogether using microchamber technique. In a selected group of male subjects with normal, doubtful, and pathological semen analyses biometrical analyses of sperm morphology and motility were performed. Sperm morphology is best described by the variation of the head size and by the average midpiece width. Motility is best described by % motile spermatozoa and mean velocity determined 1 hour after semen collection. Biometrical semen analyses are superior to subjective evaluations regarding degree of information, objectivity, and reproducibility.

Cell Survival↗
PubMed1979

Hormonal influences on the dog prostate--a correlation study with light microscopy, transmission and scanning electron microscopy.

Dog prostates under defined hormonal influences were investigated by light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The normal acinar cell apices exhibited well-developed, densely packed microvilli. TEM demonstrated numerous secretory granules, indicating a high secretory activity. Following castration, the acinar cells of the dog prostate showed rounded apices. Most of the microvilli disappeared and only knob-like protrusions were seen. Castrated dogs following administration of 3 alpha-androstandiol showed fewer microvilli than the controls; however, a well-developed undulating surface could be observed. Castrated dogs given 3 alpha-androstandiol and cyproterone acetate showed almost completely atrophic glandular cells. Prostates of dogs with spontaneous benign prostatic hyperplasia (BPH) were characterized by pleomorphism of cell shapes and surfaces. The different hormonal influences induced changes of the prostatic surface structures and secretory activity.

Androstanols↗
PubMed1979

Comparative scanning and transmission electron microscopy of the prostatic gland in different species (mouse, rat, dog, man).

Man, dog, rat and mouse prostatic glandular cells were compared by light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). In rodents and dogs, a merocrine secretion exists, and in these species the undulating surface represented a confluence of secretory granules. The prominent secretory blebs observed in dog and human benign prostatic hyperplasia (BPH) corresponded to apocrine secretions. Also variations in the amount of secretory activity were seen. Androgenic hormones were responsible for the differentiation of the prostatic epithelial cells during development. Therefore, an absence of microvilli as well as the appearance of ruffles, microplicae, and bare cells were seen in the prepuberal and castrated rat. In the elderly rat and in human BPH, a pleomorphism of the apical cell surface was evident.

Age Factors↗
PubMed1978

Improved method for the rapid determination of isosorbide dinitrate in human plasma and its application in pharmacokinetic studies.

A rapid, accurate and highly sensitive method was developed for the determination of isosorbide dinitrate in human plasma. Concentrations in the lower nanogram and subnanogram range are determined by a one-step extraction of 2 ml plasma, containing 4 ng/ml nitroglycerine as internal standard, with 5.5 ml n-pentane. The extract is subjected to gas--liquid chromatography--electron capture detection analysis. The lower limit of quantitation is 200 pg/ml, but concentrations as low as 50 pg/ml are still detectable. The method allows the quantitative determination of isosorbide dinitrate plasma levels in man following a 5 mg sublingual administration up to four hours after application.

Chromatography, Gas↗
PubMed1978

A stereological study of adrenocortical cells in spontaneously hypertensive rats (shr).

The ultrastructure of SHR (Spontaneously Hypertensive Rats) fasciculata cells was compared descriptively and quantitatively with that of nonstimulated fasciculata cells of Wistar rats using sterological methods. The volume and surface densities are expressed per cm3 of cytoplasm. The smooth endoplasmic reticulum in the SHR was significantly increased compared to the control animals (surface density : 28%, volume density: 35%). Mitochondria volume remained unchanged although the inner mitochondrial membranes were significantly reduced (37%). An attempt was made to draw up a relation between sterological and biochemical data of steroid synthesis within the fasciculata cell. A genetically determined enzymatic defect in the early steps of the transformation of cholesterol to pregnenolone may exist at the level of the inner mitochondrial membrane. Whether this altered steroid metabolism is important to the etiology of hypertension in the SHR requires further investigation.

Adrenal Cortex↗
PubMed1978

Stereological study of the zona fasciculata of the adrenal cortex in stress situations (hypothermia, catabolism).

The ultrastructure of the rat fasciculata cells in stress situations, such as catabolism and hypothermia was compared descriptively and quantitatively by stereological methods with that of the nonstimulated rat fasciculata cell. The volume and surface densities are expressed per cm3 of cytoplasm, mitochondria and smooth endoplasmic reticulum. Furthermore, absolute values are given. In both stress situations the volume density of the mitochondria compared to the controls is enlarged significantly (H: 37% CA: 50%). The significant increase of the average single mitochondrium of the fasciculata cell (H: 58% CA: 58%) shows a real growth of the mitochondria in these stress situations. Also the surface density of the mitochondrial inner membranes--the mitochondrial enzymes for steroid genesis are partly located in these membranes--shows a significant increase (H: 31%, CA: 84%). Whereas the volume density of the smooth endoplasmic reticulum remains unchanged, the surface density is significantly raised (H: 44%, CA: 60%). An attempt was made to draw up a relationship between stereological and known biochemical data of steroid genesis within the fasciculata cell. An activation in both stress situations could be observed. The stereological data reflect a subcellular reaction pattern, which is similar to exogenous ACTH administration, thus indicating an endogenous ACTH liberation due to these stress conditions.

Adrenal Cortex↗
PubMed1978

[Characterization of Ca-uptake by a microsomal fraction from vascular smooth muscle].

A microsomal fraction was isolated from the media-intima of the bovine carotid artery; the preparation is a mixed fraction of membranal and mitochondrial debris, which is able to bind Ca-ions and to take them up in the presence of ATP. The Ca-uptake is activated within a pCa range from 7--5. The involvement of two different systems in the Ca-uptake is discussed. A Ca-stimulatable ATPase was demonstrated, whose relationship with a Ca-transport system could not be established, however. The substrate for Ca-uptake is MgATP; in addition, free Mg has a stimulating effect. The Na/Kratio has no influence on the Ca-uptake. The influence of the pH-value on the Ca-binding and Ca-uptake was studied. Phosphate increased the Ca-uptake, while oxalate did not. The investigated system is discussed as a model for the action of vaso-active drugs.

Adenosine Triphosphatases↗
PubMed1977

Radioimmunoassays of ethinyl-norgestrienone (R-2323) and medroxyprogesterone acetate (MPA) and their clinical applicability.

Radioimmunoassays for 2 synthetic progestins (Ethinyl-norgestrienone, R 2323 and medroxyprogesterone acetate, MPA) are demonstrated. 10 patients aged 31 to 72 years were treated with ethinyl-norgestrienone with different schedules and 3 men suffering from benign prostatic hypertrophy were treated with medroxygesterone acetate. Plasma levels of testosterone, LH, FSH were monitored before, during and after treatment.

Adult↗
PubMed1977

Stereology, a new quantitative morphological approach to study prostatic function and disease.

Although a considerable amount of quantitative biochemical data of the prostatic gland is available the current morphological information is restricted up to now to descriptive findings. Stereology is the application of mathematical axioms and allows one to quantitate three-dimensional structures from the measurement of two-dimensional cross sections thereof. The stereological techniques provide values for volumes, surfaces and number of tissue and glandular cellular components found within the prostatic gland. Four examples are presented to illustrate how quantitative morphology can be applied to study prostatic function and disease. A stereological model, which provides information on the structure of the prostatic gland is shown for the rat prostate (ventral lobe). The model consists of morphologically defined space and membrane components of the prostatic gland and the glandular cell. The alteration, induced in the glandular cells of the ventral lobe of the rat prostate by administration of a synthetic progestine (ethinyl-norgestrienone) were studied by stereological methods. An attempt was made to quantify the morphological aspects of both, the epithelial and stromal components of the normal human prostate (3rd decade of life) and of benign prostatic hyperplasia. In comparing the stereological data of the glandular prostatic cell in the normal human prostate with that in benign prostatic hyperplasia, a diminished secretory activity of the glandular cell in benign prostatic hyperplasia is indicated. A high volume density of the fibromuscular tissue, as well as an activation of the smooth muscle cell in the fibromuscular tissue is observed in benign prostatic hyperplasia.

Adult↗
PubMed1977

[Electron microscope studies on spread of Fusarium sulphureum Schlecht. in potato tuber tissue (author's transl)].

An electron microscope study has shown that the spread of Fusarium sulphureum through potato tuber tissue occurs not only intracellular but also intercellular. The spread of hyphae effected both mechanical and enzymatical. The study of cells neighbouring hyphae shows degeneration of protoplasm. Intercellular spaces of infected tissue are filled with a dark substance. It seems that these substances are fragments of cell walls which are macerated by Fusarium enzymes.

Fusarium↗
PubMed1977

[Possibilities of the quantitative structural analysis of prostate biopsies].

Stereological methods allow the determination of volumes, surfaces or number of tissue and/or cell compartments. The quantitative data on human biopsy specimens of the prostate suggest a diminution of the secretory activity of the glandular cells, while the smooth muscle cells are activated: the relative volumes of the Golgi areas and the rough endoplasmic reticulum are increased. Stereology will be a valuable tool for objective search on hormonal dependence of the glandular as well as the smooth muscular cells. Therein, the role of the smooth muscle cells in benigh prostatic hyperplasia should be focused.

Biopsy↗
PubMed1977

Ultrastructural stereology: a new approach to the study of prostatic function.

Stereology is a method used to obtain quantitative information of structural changes at the light and electron microscopic level. The basic principles of stereology are outlined below. This paper shows how stereologic techniques can be used to obtain structural data from histologic and electron micrographs of intact tissue and cells. A morphometric model, which provides information on the structure of the prostatic gland has been developed for the rat prostate. The model consists of morphologically defined space and membrane compartments of the prostatic gland and the glandular cells. The alterations, induced in the glandular cells of the ventral lobe of rat prostate by the administration of a synthetic progestin (ethinyl-norgestrienone), were studied by electron microscopy. The results presented are relative to a cubic centimeter of prostatic tissue, a cubic centimeter of acinar parenchyma, and glandular cell cytoplasm. An attempt to relate stereologic and biochemical data is shown.

Animals↗
PubMed1976

[Effect of long-term treatment with synthetic oestrogens on plasma lipids and arterial vessels in male rabbits (author's transl)].

The effects of long-term treatment with synthetic oestrogens (Retalon retard, Sanabo Ltd., Wien, 5 mg/kg i.m. at weekly intervals) were investigated in 12 male rabbits and compared with the data obtained in 9 saline-treated control animals. After 6 months of treatment the oestrogen group showed significantly higher plasma phospholipid (p less than 0.005) and cholesterol (p less than 0.01) concentrations than the control group. However, histological examination of various important arterial vessels (the aorta and the coronary, cerebral, limb and renal arteries) revealed no pathological changes indicative of premature atherosclerosis in either the oestrogen group or in the control group. It is concluded that long-term treatment with synthetic oestrogens does not result in a higher incidence of atherosclerosis in rabbits.

Animals↗