Regulation of oxygen consumption in perfused rat liver: decrease by α-sympathetic nerve stimulation and increase by the α-agonist phenylephrine

In livers perfused with Krebs-Henseleit bicarbonate buffer containing bovine red cells, 5 mM glucose and 2 mM lactate, electrical stimulation round the hepatic artery and the portal vein caused via qw451g642/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-receptors a decrease in oxygen consumption and portal flow, an increase in glucose output and a switch from lactate uptake to output.In livers perfused with erythrocyte- and substrate-free buffer both in a volume- or pressure-constant system stimulation of the liver nerves resulted in similar changes. Infusion of the qw451g642/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-agonist phenylephrine mimicked the metabolic and hemodynamic nerve effects, but led to an increase in oxygen uptake. The converse effects of qw451g642/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-sympathetic nerve stimulation and qw451g642/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-agonist infusion on oxygen consumption indicate either a different mode of action or a complex mechanism with opposing metabolic and hemodynamic components.     

Association between serum-soluble CD8 levels and parameters of immune activation in patients with human immunodeficiency virus infection

Summary We compared the serum concentrations of soluble CD8 with the immune activation markers neopterin, interferon-qw3253t5221800/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">, tumour necrosis factor-qw3253t5221800/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">, soluble CD4, and with CD34⁺ and CD38⁺ T-cell counts in patients with human immunodeficiency virus (HIV) infection. The majority of patients had increased concentrations of soluble CD8, interferon-qw3253t5221800/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> and neopterin, and various significant correlations existed between them. Our results support the view that enhanced soluble CD8 levels indicate activated CD8⁺ T cells in patients with HIV infection.Abbreviations sCD8 serum-soluble CD8 - sCD4 serum-soluble CD4 - IFN-qw3253t5221800/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> interferon-qw3253t5221800/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> - TNF qw3253t5221800/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">=tumour necrosis factor-qw3253t5221800/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> - HIV human immunodeficiency virus - AIDS acquired immunodeficiency virus     

Circulating E-Selectin Levels in Chronic Hepatitis C Patients with Normal or Elevated Transaminase Before and After Alpha-Interferon Treatment

E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN qw0h2m415g61q156/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0"> at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values.     

Chemosensitivity and radiosensitivity profiles of four new human epithelial ovarian cancer cell lines exhibiting genetic alterations in BRCA2, TGFbeta-RII, KRAS2, TP53 and/or CDNK2A

To address the cellular basis for the response to ovarian cancer treatment, we characterized the chemosensitivity and radiosensitivity of four human epithelial ovarian cancer cell lines that harbor different genetic alterations. The TOV-21G, TOV-81D, OV-90, and TOV-112D cell lines were derived from ovarian tumors (TOV) or ascites (OV) from chemotherapy- and radiotherapy-naive patients and were characterized by their mutation spectrum of BRCA2, TGFqw3gk/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-RII, KRAS2, TP53, and CDKN2A. Cells were monitored for survival following exposure at various concentrations to different cytotoxic agents including cisplatin, camptothecin or paclitaxel or to different doses of qw3gk/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-irradiation. At the lowest doses, the TGFqw3gk/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-RII-mutated and KRAS2-mutated cell line, TOV-21G, and the BRCA2-mutated cell line, TOV-81D, demonstrated a significantly higher sensitivity to cisplatin and qw3gk/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-irradiation than the TP53-mutated cell lines, TOV-112D and OV-90. At higher doses, differences between the TP53-mutated lines were observed with TOV-112D being less sensitive to cisplatin than OV-90 that also harbors a CDNK2A mutation. All cell lines were similarly sensitive to high doses of qw3gk/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-irradiation. In contrast, sensitivity to camptothecin or paclitaxel was not significantly different between all cell lines, irrespective of the mutation status of BRCA1, BRCA2, TGFqw3gk/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-RII, KRAS2, TP53, and CDKN2A. The observed responses to treatment are consistent with the current knowledge concerning BRCA2, TGFqw3gk/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-RII, KRAS2, TP53, and/or CDKN2A aberrant function.The first and second authors contributed equally to this work.     

γ-Glutamyltransferase test as a new tool for identification of seminal stains

Summary A simple qualitative method for identification of seminal stains based on a high activity of qw/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-glutamyltransferase (qw/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-GTP) in human semen is described. It employs the release of qw/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-naphthylamine from N-qw/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-glutamyl-qw/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-naphthylamide by the qw/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-GTP action; qw/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-naphthylamine couples with Fast Garnet GBC salt to produce a strong brownish-red color. The data on its simplicity, specificity, and stability show that the present method is suitable for medicolegal examination of seminal stains as a preliminary test.     

Therapy of MS

The era of disease-modifying drugs (DMDs) in multiple sclerosis (MS) treatment began in the 1990s, first with interferon-β (IFNβ), and the number of agents has increased steadily since then. Currently, there are six different parenteral formulations approved for MS treatment and many other oral and parenteral ones are in different stages of investigation or awaiting approval by federal agencies.     

Fortschritte der molekularen Endokrinologie

Summary Recent advances towards an understanding of the molecular basis of hormone action are described. Main attention is focussed on qw8u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-adrenergic action and on signal transmission from qw8u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-adrenoceptor to adenylate cyclase including signal amplification.Molecular properties of guanine nucleotide binding amplifier proteins are recapitulated. The hormone-sensitive membrane-bound adenylate cyclase system is characterized as a multicomponent system made up of several heterologous subunits that reversibly interact with each other by means of association-dissociation reactions. These properties are exemplified by the role of inhibitory and stimulatory guanine nucleotide proteins which communicate with each other through the intervention of qw8u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">,qw8u/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">-subunits which are common to both. Once a second messenger such as cyclic AMP (cAMP) is formed, in response to a stimulatory hormone, a cascade of reactions is triggered which profoundly change cellular metabolism and are responsible for pleiotropic hormone action. For example, the group of hormones whose action is transmitted by means of the second messenger cAMP sets in motion a series of protein phosphorylation reactions, starting with the activation of a cAMP-dependent protein kinase and involving a series of specific protein kinases and phosphoprotein phosphatases and inhibitor and modifier proteins. The activity of several key enzymes controlling cell metabolism and substrate flux through metabolic pathways is regulated by phosphorylation-dephosphorylation reactions as are ion-channel forming proteins and proteins with other important cellular functions.Recent findings on signal transmission chains liberating intracellular calcium are summarized. Calcium-releasing hormones actvia activation of polyphosphatidylinositolphosphodiesterase which cleaves phosphatidylinositol 4,5-bis-phosphate to diacylglycerol and inositoltrisphosphate. Diacylglycerol in turn activates protein kinase C, whereas inositoltrisphosphate is a novel second messenger which liberates calcium from intracellular stores perhaps by binding to a specific receptor protein. Of special interest is the role of oncogene-coded proteins in polyphosphatidylinositol metabolism. Cellular and viral qw8u/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">rasqw8u/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> genes deserve special attention, because they code for GTP-binding proteins which have properties similar to those of the GTP-binding proteins of the adenylate cyclase system, although the qw8u/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">rasqw8u/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> proteins with molecular weight 21 kDa do not act as transducers in the adenylate cyclase system. A hypothetical scheme for a possible role of oncogenic qw8u/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">rasqw8u/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> proteins in uncontrolled production of inositoltrisphosphate and diacylglycerol is presented.Striking similarities between the hormonally activated adenylate cyclase system and the rhodopsin activated amplification cascade have led to the assumption that GTP binding and hydrolyzing amplifier proteins which occur in several biological systems belong to a class of proteins, very old from an evolutionary standpoint, which fulfil their biological function by means of conformational transitions made possible by reversible association-dissociation reactions. The argument for GTP binding proteins as evolutionary relatives is supported by the fact that all these proteins are targets for ADP-ribosyltransferase reactions catalyzed by pathogenic toxins. In the case of the adenylate cyclase system the action of cholera toxin and ofBordetella pertussis toxin on activating (G _s ) and inhibiting (G _i ) guanine nucleotide binding proteins are pertinent. These toxin actions can explain, at least in part, some of the pathological sequelae ofBordetella pertussis and cholera toxin infections. In the case of theBordetella pertussis infection the ADP-ribosylated, covalently modified inhibitory GTP-binding protein (G _i ) becomes nonfunctional so that adenylate cyclase is no longer under the inhibitory influence. This in turn leads to increased, uncontrolled cAMP production and to pathological consequences such as hypoglycemia.Cholera toxin modifies the stimulatory GTP-binding protein (G _s ) and prevents the termination reaction due to GTP hydrolysis. Consequently, G_s becomes persistently activated, leading in turn to a prolonged and persistent activation of adenylate cyclase. Differences in the action of these and other toxins result from different substrate specificities and from differences in cellular targets as well, because only certain cell types have a toxin receptor. Thus, the comprehension of the hormonal signal transmission chain from qw8u/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-adrenoceptor to adenylate cyclase on a molecular level has provided, as a welcome side product, a satisfactory understanding of the molecular mechanisms of the action of some toxins and of the pathophysiological consequences resulting from infection of man with the toxin-producing, pathogenic infectious agents.An important application in neurobiology of the new findings concerning hormonal signal transmission chains is the molecular analysis of the learning process in the marine snailAplysia californica and its relationship to neurotransmitter-activated signal transmission pathways.

Die Arbeiten des Autors werden gefördert im SFB 176 der Universität Würzburg, durch die Thyssen-Stiftung und den Fonds der Chemischen Industrie e.V.     

Trennung der intestinalen β-Galactosidasen beim lactose-intoleranten Erwachsenen durch Ultrazentrifugation im Dichtegradienten

Zusammenfassung Bei 11 erwachsenen Versuchspersonen mit Lactose-Intoleranz konnten bei der Trennung der intestinalenqw15462n116/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-Galactosidasen im Dichtegradienten die qw15462n116/xxlarge8222.gif" alt="ldquor" align="MIDDLE" BORDER="0">neutraleqw15462n116/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0"> Bürstensaum-Lactase und die qw15462n116/xxlarge8222.gif" alt="ldquor" align="MIDDLE" BORDER="0">saureqw15462n116/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0"> lysosomale Lactase nachgewiesen werden. Im Vergleich zu lactose-toleranten Erwachsenen war die Bürstensaum-Lactase stark vermindert. Die Hetero-qw15462n116/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-Galactosidase, die bei lactose-toleranten Erwachsenen als langsam sedimentierendes Enzym nachweisbar ist, fehlte bei allen 11 Versuchspersonen.Diese Arbeit wurde durch die Stiftung Volkswagenwerk und durch das Landesamt für Forschung Nordrhein-Westfalen unterstützt.     

Percutaneous Absorption of Biologically-Active Interferon-gamma in a Human Skin Graft-Nude Mouse Model

Purpose. Topical delivery has been suggested to reduce systemic side effects while targeting cytokines for the treatment of certain skin conditions. Liposomes have been proposed as an enhancing agent for such a delivery. We have tested the potential of liposomes to augment the uptake of biologically active recombinant human interferon-gamma (rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">) into human skin lacking adnexa in an in vivo model. Methods. Stable grafts of human skin on nude mice were used to test aqueous formulations of rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> containing or lacking liposomes composed of phosphatidylcholine and cholesterol. Transport of rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> was assessed by monitoring the stimulated expression of intercellular adhesion molecule-1 (ICAM-1) by keratinocytes by light-level immunomicroscopy and ELISA. Results. A single application of liposomal rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> increased ICAM-1 levels in the epidermal basal and suprabasal cell layers of grafts. Continued application maintained this response. An aqueous formulation of rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> or liposomes alone applied to grafts failed to induce an ICAM-1 response. Preliminary studies suggested that at least some of the lipids applied in the liposomal formulation also entered the epidermis. Conclusions. Using a nude mouse-human skin graft model lacking adnexa, we have demonstrated that a liposomal formulation can augment the uptake of a biologically-active human cytokine, rhIFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">, into the epidermis of viable human skin. The therapeutic application of topical IFN-qw7m/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> delivery remains to be evaluated.     

Pathological study on a severe sialidosis (α-neuraminidase deficiency)

Summary A 56-day-old infant with qw6j03467k8777x8/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-neuraminidase deficiency, whose clinical features included severe edema of extremities and ascites which resembled those in severe infantile sialidosis, was autopsied. Perforation, whose pathogenesis was unclear, was found on the descending portion of the duodenum. Light and electron microscope studies showed that neurons in the cerebral and cerebellar corticies, and the thoracic spinal cord contained membrane-bound vacuoles but no membranous cytoplasmic bodies. Zebra bodies were found only in the neurons of the spinal cord. The neurons in the paraganglion and in the Auerbach's myenteric plexus were also distended with numerous membrane-bound vacuoles. Hepatocytes, endothelial cells and Kupffer cells in the liver and glomerular and tubular epithelial cells in the kidney were swollen with a number of vacuoles although the patient showed none of the clinical features of renal involvement. These pathological changes were similar to those in nephrosialidosis reported by Le Sec et al. [Arch Fr Pediatr 35:819–829 (1978)].