Organelle-free cytoplasmic volume fraction of rabbit retinal Müller (glial) cells.

Retinal Müller (glial) cells are thought to act as "cables" carrying spatial buffering K+ currents from the sites of neuronal release into the reservoir of the vitrous body. In order to calculate the amplitude of such currents it is necessary to know the intracellular volume fraction which is able to carry these currents. Thus, this organelle-free volume fraction was measured in transmission electron microscopic photograms of rabbit Müller cells.

Gas chromatographic-mass spectrometric investigation of four commercial pristane (2.6.10.14-tetramethylpentadecane) preparations used for plasmacytoma induction in BALB/c mice.

The most widely studied model of plasmacytomagenesis is the induction of plasmacytomas by intraperitoneal injections of pure alkanes such as pristane (2.6.10.

Cytophotometric and interference microscopic investigations in carcinomas of the oral cavity.

The DNA content and the nuclear dry mass of 18 keratinized squamous cell carcinomas and their metastases, of one adamantinoma recurrence and two adenoid cystic carcinomas of the oral cavity were determined in comparison to the normal buccal mucosa using Feulgen scanning cytophotometry and interference microscopy. The squamous cell carcinomas could be classified into five groups based on their DNA distribution pattern. The nuclear dry mass and its variation were found to be different from the normal mucosal epithelial cells in all cases.

6-Phosphofructo-2-kinase and fructose-2,6-bisphosphatase from Saccharomyces cerevisiae.

In permeabilized yeast cells 6-phosphofructo-2-kinase and fructose-2,6-bisphosphatase are studied during growth. It is shown that in yeast at least two fructose 2,6-bisphosphate degrading enzyme activities occur, differing in pH profile and in their substrate affinities. The activities of 6-phosphofructo-2-kinase and of fructose-2,6-bisphosphatases drop in the exponential and the transition phase while the activity of the alkaline phosphatases steadily increases.

Purification of cytochrome P-450 from n-hexadecane-grown Acinetobacter calcoaceticus.

A convenient procedure for the purification of cytochrome P-450 from an n-alkane-assimilating strain of the bacterial species Acinetobacter calcoaceticus has been elaborated. The cytochrome P-450 of n-hexadecane-grown cells was found to be distributed in cell-free extracts among particulate and soluble subcellular fractions. For isolation, cytochrome P-450 was extracted from particulate fractions by addition of Triton X-100 to the buffer.

Experimentally induced acute changes in veins studied by scanning microscopy.

Endothelial damage caused by hypoxia and the local administration of Varicocid, or by using vascular clamps on the jugular vein of rabbits, was studied under a scanning electron microscope. Adhering platelets and fibrin were found only in the acutely damaged veins with endothelial defects. Swelling and vacuolization of endothelial cells did not induce intravascular coagulation.

Differences in response of acetylcholinesterase to diisopropylfluorophosphate in the mesencephalic raphe region. A microelectrophoretic, histochemical, and biochemical study in albino rats.

To demonstrate the DFP-effects on the AChE of the mesencephalic raphe region albino rats were investigated using the pharmaco-histochemical method of Butcher et al. (1975). At several times after 1 mg DFP/kg body weight, the histochemical reactions in certain AChE-containing neurons were measured semiquantitatively and compared with biochemical data.

Allogeneic bone marrow transplantation for leukaemia and aplastic anaemia. Results of the Leipzig BMT Group.

In acute leukaemias there was a stable plateau in the survival curve at 45% after two years if grafted in first complete remission (n = 20) but only 13% of the patients are disease-free alive if grafted in a more advanced stage of the disease (n = 8). In 16 patients transplanted for chronic myeloid leukaemia the overall survival is 40%, in cases with graft-versus-host disease (GVHD) prevention by cyclosporine survival rate could be improved. Only 8 patients with severe aplastic anaemia, partially in low performance status were able to be transplanted; three died of infections, another by acute GVHD.

In vitro selective glycogen depletion of frog twitch and slow muscle fibres.

Glycogen as measured histochemically with periodic acid-Schiff (PAS) reaction was depleted in frog muscle fibres following electrical stimulation of the nerve. The types of the muscle fibres examined were identified in serial cryostat sections. We used appropriate stimulation regimes which provide a heavy work load only for twitch fibres (at low stimulation frequency) or selectively for slow fibres (contractures in response to high frequency stimulation or pharmacological agents).

Interaction of electrically charged drug molecules with phospholipid membranes.

Model membranes (egg-yolk PC liposomes) were exposed to the cationic form of amphiphilic drugs. Microelectrophoresis was used to measure the change of the electrokinetic potential as a function of the drug concentration. By use of the Gouy-Chapman theory the surface potential and surface charge density were calculated.

Evidence for phosphorylation of yeast phosphofructokinase.

Radioactively labelled material from yeast cells grown in the presence of [32P]phosphate was specifically recognized by antibodies raised against yeast phosphofructokinase. Purified yeast phosphofructokinase was phosphorylated in a cyclic AMP-independent manner by a protein kinase enriched from yeast extracts. This phosphorylation occurred specifically on the beta-subunit, and 0.

Profile of isoacids in rumen fluid and influence of added isoacids on in sacco dry matter disappearance of untreated and ammonia treated wheat straw.

The influence of type of diet and time after feeding on concentration of isoacids in rumen fluid of 6 fistulated sheep were investigated. The concentration of isoacids in rumen fluid was higher in diets rich in concentrate and protein (5.6) than in roughage diets (3.

106Ru/106Rh plaque radiotherapy for malignant melanomas of the choroid. With follow-up results more than 5 years.

Therapeutic results are presented with follow-up examinations of at least 5 years (min. 5 years, max. 22 years) after 106Ru/106Rh plaque radiotherapy of posterior uveal melanomas.

Influence of dietary niacin on volatile fatty acids in rumen liquid of sheep and rumen dry matter degradability of untreated and ammonia-treated wheat straw.

Three rumen fistulated sheep were fed with roughage (1200 g artificially dried grass) or a concentrate/roughage diet (600 g concentrate, 400 g artificially dried grass per animal and day). The diets were unsupplemented or 0.5, 1 and 2 g niacin per animal and day were added.

Effect of dietary choline on volatile fatty acids in rumen liquid of sheep and rumen dry matter degradability of untreated and ammonia-treated wheat straw.

Three rumen fistulated wethers consumed a roughage (1200 g artificially dried grass) or a concentrate/roughage diet (600 g concentrate, 400 g dried grass per animal and day). The diets were unsupplemented or 0.5, 1 or 2 g choline per animal and day were added.

Some aspects of dexamethasone binding in the old rat liver.

The maximal glucocorticoid responsiveness and the adaptation degree are reduced in old rat liver as demonstrated by cortisol stimulation of RNA polymerases. Nevertheless the concentration of unoccupied 3H-dexamethasone binding sites in molybdate-stabilized cytosol of adrenalectomized old animals is significantly increased in comparison with young adult rats. The KD constants showed an increasing tendency, but not a significant one.

Metabolic differences between AGA- and SGA-infants of very low birthweight. I. Relationship to intrauterine growth retardation.

Metabolic response to human milk feeding was studied in 12 appropriate (AGA) and 12 small for gestational age (SGA) infants of very low birthweight (VLBW) on the eighth day of life. Protein intake ranged from 1.98 to 2.

Flow cytometric DNA histograms and type of growth.

DNA histograms of human tumors should be interpreted together with the type of growth. In order to prove this connection the Ehrlich ascites tumors of 144 mice were investigated by absolute cell counting and flow cytometry. The exponential, transition and steady-state phases of tumor development were defined as types of growth based on the logistic function (Verhulst-Pearl).

Histoautoradiographic detection of 3H-thymidine and 3H-proline in the vascular wall of domestic swine in experimental atherosclerosis. Is there an effect of saturated/unsaturated fatty acids in high cholesterol diet?

In vitro labeling of arterial wall samples from domestic swine with tritiated thymidine or proline was used to establish the effect of unsaturated (sunflower oil) or saturated (beef tallow) fatty acids in the presence of enteral cholesterol on DNA and collagen synthesis. Histoautoradiography of samples incubated in vitro gives labeling patterns and indices comparable to in vivo labeling. Preliminary results show that these nutrient fats do not differ in their effect on the DNA and collagen synthesis of vascular wall cells both in the presence and absence of intimal changes.

Syngeneic transplantation of rat pancreatic islets into the spleen. Light and electron microscopical findings.

An islet transplantation model was established with the two congeneic Lewis rat strains LEW.1W and LEW.1A, which were made diabetic by a single i.

Development of hypothalamic obesity in growing rats.

Administration of monosodium glutamate to neonate rats causes hypothalamic lesions in the region of the nucleus arcuatus and the eminentia mediana, followed by massive accumulation of triglycerides, diminished secretion of growth hormone, reduced body length and organ weights and diminished number of adipocytes (hypoplastic-hypertrophic obesity). Locomotor activity of obese animals is reduced by about 50%. Food intake is increased by about 10% during growth and development of obesity but decreased beneath the level of that in control animals in the stationary phase of obesity.

The use of separated subunits of yeast phosphofructokinase for the isolation of subunit-specific antibodies from polyclonal antisera.

The subunits alpha and beta of yeast phosphofructokinase have been separated under denaturing conditions by ion exchange chromatography and then separately immobilized on Sepharose 6MB. The resulting affinity gels were used to fractionate polyclonal phosphofructokinase antisera from rabbit into subunit-specific antibodies. In addition to subunit-specific antibodies also antibody fractions which recognize both types of subunits of phosphofructokinase could be desorbed from the affinity gels.

Noradrenergic sprouting and beta-adrenergic receptor binding in the lateral geniculate nucleus of rats after unilateral visual cortex ablation.

One and two weeks after unilateral visual cortex (VC) ablation beta-adrenergic receptor binding is increased in the lateral geniculate nucleus (LGN) of both sides. 6 month later beta-receptor binding in the LGN is decreased again and no differences to untreated control animals are detectable. Using the glyoxylic acid fluorescence method for the visualization of amines a transient increase in the density of noradrenergic fibers in the dorsal part of the ipsilateral LGN can be demonstrated with a maximum 2 weeks after VC ablation.

Haemorheological investigations with benzotriazines in vitro.

Benzotriazines are a new group of substances with surprisingly hemorheological effects. Especially red-cell deformability is influenced. In the case of decreased deformability some benzotriazines are comparable to pentoxifylline.