Medizin - Open Access LMU - Teil 04/22

Matrix-free calcium in isolated chromaffin vesicles

Isolated secretory vesicles from bovine adrenal medulla contain 80 nmol of Ca2+ and 25 nmol of Mg2+ per milligram of protein. As determined with a Ca2+-selective electrode, a further accumulation of about 160 nmol of Ca2+/mg of protein can be attained upon addition of the Ca2+ ionophore A23187. During this process protons are released from the vesicles, in exchange for Ca2+ ions, as indicated by the decrease of the pH in the incubation medium or the release of 9-aminoacridine previously taken up...

Minimal requirements for exocytosis

The membrane-permeabilizing effects of streptolysin O, staphylococcal alpha-toxin, and digitonin on cultured rat pheochromocytoma cells were studied. All three agents perturbed the plasma membrane, causing release of intracellular 86Rb+ and uptake of trypan blue. In addition, streptolysin O and digitonin also damaged the membranes of secretory vesicles, including a parallel release of dopamine. In contrast, the effects of alpha-toxin appeared to be strictly confined to the plasma membrane, and n...

α-Toxin permeabilized rat pheochromocytoma cells

The channel forming α-toxin of Staphylococcus aureus (about 50 μg/ml) markedly reduces the Ca2+ requirement for dopamine release by the rat pheochromocytoma cell line (PC 12). Maximal secretion by intact cells requires approximately 1 mM Ca2+, whereas release by α-toxin-permeabilized cells can already be triggered with μM concentrations of Ca2+. The latter process reaches a plateau at about 1 μM free Ca2+ and increases again with 10–20 μM free Ca2+. The sensitivity to low concentrations of Ca2+ ...

Tödliche Meningoencephalitiden aus forensischer Sicht

Rechtliche Aspekte der Kontrastmittelanwendung, speziell bei der Ausscheidungsurographie

A long and complex enhancer activates transcription of the gene coding for the highly abundant immediate early mRNA in murine cytomegalovirus

Using the simian virus 40 "enhancer trap" approach, we have identified a transcription enhancer located just upstream of the major immediate early gene of murine cytomegalovirus. This enhancer has several striking properties. (.) Together with the enhancer ofhuman cytomegalovirus, it is the strongest transcription enhancer found to date. (ö) It is an extremely long enhancer, spanning >700 base pairs. (ÜI) It consists of a rather complex pattern of sequence repeats, the longest of which is 181...

Characterization of the major immediate-early polypeptides encoded by murine cytomegalovirus

The immediate-early (IE) infected cell proteins induced by the murine cytomegalovirus (Smith strain) were studied. These polypeptides were identified as IE proteins by their synthesis in the presence of actinomycin D after removal from a protein synthesis block mediated by cycloheximide. By using a murine antiserum against murine cytomegalovirus, three abundant polypeptides of 89, 84, and 76 kilodaltons (kd) were immunoprecipitated. The three major proteins are phosphorylated but not glycosylate...

Interstitial murine cytomegalovirus pneumonia after irradiation: characterization of cells that limit viral replication during established infection of the lungs

Interstitial pneumonia associated with viral replication in lung tissue was observed after cytomegalovirus infection of total-body gamma-irradiated mice, whereas in noncompromised hosts the lungs were not affected and virus multiplication was restricted to the salivary glands. The radiation damage could either predispose normally nonpermissive cell types for productive infection or abrogate an immune control of the tissue manifestation of infection by elimination of lymphocytes. Adoptive transfe...

Beidseitige Hodentumoren bei einem 21 Jahre alten Patienten mit congenitalem adrenogenitalem Syndrom

Todesdefinition - insbesondere bei Neu- und Frühgeborenen

Facial reconstruction with implants of porous polyethylene

Die Bedeutung morphologischer Befunde am Gehirn beim posttraumatischen Suicid

Überblick über die körperlichen Untersuchungen im Institut für Rechtsmedizin der Universität München unter besonderer Berücksichtigung von Sexualdelikten

Implantate und Transplantate bei der Korrektur von Stirndefekten

Experimenteller Trachealersatz

Porous polyethylene in reconstructive head and neck surgery

Plasma atrial natriuretic factor in patients with cirrhosis

Kinetische Studien zur Aufklärung des Sekretionsmechanismus von Insulin am perfundierten Rattenpankreas

Chirurgische Konzepte für die Wiederherrstellung der fehlenden Ohrmuschel

54-jähriger Patient mit schwerer Dyspnoe 6 Monate nach Implantation eines peritoneo-venösen Shunts

Activity-dependent excitability changes in normal and demyelinated rat spinal root axons

Myelinated nerve fibres with a reduced safety factor for conduction due to demyelination are easily blocked by trains of impulses. To find out why, in vivo recordings from rat ventral root fibres demyelinated with diphtheria toxin have been supplemented with in vivo and in vitro recordings from normal fibres. Despite a small rise in extracellular potassium activity, normal fibres were invariably hyperpolarized by intermittent trains of impulses. This hyperpolarization resulted in an increase in ...

An intracellular analysis of gamma-aminobutyric-acid-associated ion movements in rat sympathetic neurones

Double-barrelled ion-sensitive micro-electrodes were used to measure the changes of the intracellular activities of Cl-, K+, and Na+ (aiCl, aiK, aiNa) in neurones of isolated rat sympathetic ganglia during the action of gamma-aminobutyric acid (GABA). The membrane potential of some of the neurones was manually 'voltage clamped' by passing current through the reference barrel of the ion-sensitive micro-electrode. This enabled us to convert the normal depolarizing action of GABA into a hyperpolari...

Processing peptidase of Neurospora mitochondria

Subunit 9 (dicyclohexylcarbodiimide binding protein, 'proteolipid') of the mitochondrial F1F0-ATPase is a nuclearly coded protein in Neurospora crassa. It is synthesized on free cytoplasmic ribosomes as a larger precursor with an NH2-terminal peptide extension. The peptide extension is cleaved off after transport of the protein into the mitochondria. A processing activity referred to as processing peptidase that cleaves the precursor to subunit 9 and other mitochondrial proteins is described and...

Sex chromosome positions in human interphase nuclei as studied by in situ hybridization with chromosome specific DNA probes

Two cloned repetitive DNA probes, pXBR and CY1, which bind preferentially to specific regions of the human X and Y chromosome, respectively, were used to study the distribution of the sex chromosomes in human lymphocyte nuclei by in situ hybridization experiments. Our data indicate a large variability of the distances between the sex chromosomes in male and female interphase nuclei. However, the mean distance observed between the X and Y chromosome was significantly smaller than the mean distanc...

Proteinaceous receptors for the import of mitochondrial precursor proteins

Mild trypsin treatment of isolated Neurospora mitochondria strongly inhibits their ability to bind and import the precursors of several mitochondrial proteins. Evidence is presented for two proteins, the ADP/ATP carrier and the mitochondrial porin, that specific binding of the precursors to the outer surface of the mitochondria is affected by the protease treatment. We suggest that the receptors that mediate the import of these two precursors are proteinaceous. Treatment of mitochondria with ela...

Voraussage und tatsächliche Aussage über das thermische Empfinden bei standardisierter Frei-Luft-Bewegungstherapie

Die vorliegende Studie befaßt sich mit dem thermischen Empfinden von Patienten während Freiluft-Bewegungstherapie und dessen Vorhersage. Wir untersuchten zwei Modellverfahren zur Vorhersage des zu erwartenden thermischen Empfindens PMV und fanden bei der Anwendung der Modelle im Freiland noch Probleme: Das thermische Empfinden der Probanden wurde als zu kühl beurteilt. Zusätzlich wiesen die Ergebnisse eine große Streuung auf. Die deutlichste Abweichung zwischen Vorhersage und Aussage über das th...

Zur bioklimatischen Beurteilung von Terrainkurwegen

Plasma levels of Human Granulocytic Elastase-alpha-Proteinase Inhibitor Complex (E-alpha1PI) in Leukemia

Granulozytäre Elastase als lsosomales Markerenzym für pathobiochemische Veränderung bei entzündlichen Erkrankungen

An Enzyomatic Assay Convenient for the Control of Aprotinin Levels During Proteinase Inhibitor Therapy