Stearns County, Minnesota, 1855 - 1915

Elektronische Version der gedr. Ausg. 198

Heparinase selectively sheds heparan sulphate from the endothelial glycocalyx

A healthy vascular endothelium is coated by the endothelial glycocalyx. Its main constituents are transmembrane syndecans and bound heparan sulphates. This structure maintains the physiological endothelial permeability barrier and prevents leukocyte and platelet adhesion, thereby mitigating inflammation and tissue oedema. Heparinase, a bacteria] analogue to heparanase, is known to attack the glycocalyx. However, the exact extent and specificity of degradation is unresolved. We show by electron microscopy, immunohistological staining and quantitative measurements of the constituent parts, that heparinase selectively sheds heparan sulphate from the glycocalyx, but not the synclecans

Perspectives in Microvascular Fluid Handling: Does the Distribution of Coagulation Factors in Human Myocardium Comply with Plasma Extravasation in Venular Coronary Segments?

Background: Heterogeneity of vascular permeability has been suggested for the coronary system. Whereas arteriolar and capillary segments are tight, plasma proteins pass readily into the interstitial space at venular sites. Fittingly, lymphatic fluid is able to coagulate. However, heart tissue contains high concentrations of tissue factor, presumably enabling bleeding to be stopped immediately in this vital organ. The distribution of pro- and anti-coagulatively active factors in human heart tissue has now been determined in relation to the types of microvessels. Methods and Results: Samples of healthy explanted hearts and dilated cardiomyopathic hearts were immunohistochemically stained. Albumin was found throughout the interstitial space. Tissue factor was packed tightly around arterioles and capillaries, whereas the tissue surrounding venules and small veins was practically free of this starter of coagulation. Thrombomodulin was present at the luminal surface of all vessel segments and especially at venular endothelial cell junctions. Its product, the anticoagulant protein C, appeared only at discrete extravascular sites, mainly next to capillaries. These distribution patterns were basically identical in the healthy and diseased hearts, suggesting a general principle. Conclusions: Venular extravasation of plasma proteins probably would not bring prothrombin into intimate contact with tissue factor, avoiding interstitial coagulation in the absence of injury. Generation of activated protein C via thrombomodulin is favored in the vicinity of venular gaps, should thrombin occur inside coronary vessels. This regionalization of distribution supports the proposed physiological heterogeneity of the vascular barrier and complies with the passage of plasma proteins into the lymphatic system of the heart. Copyright (C) 2010 S. Karger AG, Base

Проект установки получения синтез-газа

ВКР 91 страницу, 6 рисунков, 40 таблиц, 24 литературных источника. Ключевые слова: синтез-газ, конверсия, применение синтез-газа, сырье, природный газ, технологическая схема, производство, метан, метанол. Объект разработки: производство синтез-газа методом паровой каталитической конверсии природного газа. Цель работы: изучение всех физико - химических свойств процесса и их влияния на протекание реакции, а также конструирование основного аппарата установки получения синтез - газа. В результате исследования выполнен расчет материального и теплового балансов, также конструктивный и механический расчеты, на основании которых был выполнен чертеж основного аппарата. ВКР выполнена на кафедре ТОВПМ ст. группы 2Д2А Якимовой В.А., под руководством к.х.н. Мананковой А.А.The final qualifying work contains 91 page, 6 figures, 40 tables and 24 literature sources. Content words are conversion, synthesis gas. The object of the development is the production of synthesis gas by catalytic steam reforming of natural gas. The mission is the study of physical - chemical properties of the process and their influence on the reaction, as well as the construction of the main unit installation producing synthesis - gas. The study was carried out payment of material and heat balances, the constructive and mechanical calculations, drawing on the basis of which the main unit was made. The final qualifying work carried out at the Department of TOVPM student group 2D2A Vera Yakimova, under the leadership of Candidate of Chemical Sciences Ann Manankova

The endothelial glycocalyx prefers albumin for evoking shear stress-induced, nitric oxide-mediated coronary dilatation

Background: Shear stress induces coronary dilatation via production of nitric oxide ( NO). This should involve the endothelial glycocalyx ( EG). A greater effect was expected of albumin versus hydroxyethyl starch ( HES) perfusion, because albumin seals coronary leaks more effectively than HES in an EG-dependent way. Methods: Isolated hearts ( guinea pigs) were perfused at constant pressure with Krebs-Henseleit buffer augmented with 1/3 volume 5% human albumin or 6% HES ( 200/0.5 or 450/0.7). Coronary flow was also determined after EG digestion ( heparinase) and with nitro-L-arginine ( NO-L-Ag). Results: Coronary flow ( 9.50 +/- 1.09, 5.10 +/- 0.49, 4.87 +/- 1.19 and 4.15 +/- 0.09 ml/ min/ g for `albumin', `HES 200', `HES 450' and `control', respectively, n = 5-6) did not correlate with perfusate viscosity ( 0.83, 1.02, 1.24 and 0.77 cP, respectively). NO-L-Ag and heparinase diminished dilatation by albumin, but not additively. Alone NO-L-Ag suppressed coronary flow during infusion of HES 450. Electron microscopy revealed a coronary EG of 300 nm, reduced to 20 nm after heparinase. Cultured endothelial cells possessed an EG of 20 nm to begin with. Conclusions: Albumin induces greater endothelial shear stress than HES, despite lower viscosity, provided the EG contains negative groups. HES 450 causes some NO-mediated dilatation via even a rudimentary EG. Cultured endothelial cells express only a rudimentary glycocalyx, limiting their usefulness as a model system. Copyright (c) 2007 S. Karger AG, Basel

Enzymfreisetzung und Aktivierung der Kallikrein-Kinin-Systeme bei experimenteller Pankreatitis

Das klinische Bild der akuten Pankreatitis wird entscheidend durch die sekundäre Schädigung von Herz-Kreislauf-System, Lunge und Niere bestimmt. Ziel der vorliegenden Untersuchung war es, durch Messungen in venösem Pankreasblut, Pankreaslymphe und Peritonealexsudat die Kompartimente zu bestimmen, über die die systemischen Schädigungen vermittelt werden. An anästhesierten Schweinen wurden die systemischen, hämodynamischen Parameter durch gesteuerte Volumentherapie konstant gehalten. Die Schweine wurden randomisiert der Kontrollgruppe (n = 9) oder einer der Pankreatitisgruppen zugeteilt (jeweils n = 10). Die Pankreatitis wurde durch Infusion von freier Fettsäure in die Pankreasarterien (FFS) oder durch Infusion einer 5%igen Natrium-Taurocholat-Lösung retrograd in den Pankreasgang (NaT) ausgelöst. Nach Isolation des Pankreas wurde venöses Pankreasblut, Pankreaslymphe und Peritonealexsudat gewonnen und die Aktivität von Lipase, Phospholipase A und Plasmaprokallikrein sowie die Konzentration von Organkallikrein und Kininogen bestimmt. In beiden Pankreatitismodellen fand sich ein Anstieg der Enzymaktivitäten. Die höchsten Aktivitäten fanden sich im Peritonealexsudat (Phospholipase A nach 40 min: Kontrolle 10,0 U/1, NaT 72,2 U/1). In beiden Pankreatitismodellen fanden sich außerdem Hinweise für eine Aktivierung des Organkallikrein-Kinin-Systems durch den Anstieg der Organkallikreinkonzentration und den Abfall der Gesamtkininogenkonzentration. Die stärksten Veränderungen fanden sich wieder im Peritonealexsudat (Organkallikrein nach 40 min: Kontrolle 14,7 ng/ml, NaT 452 ng/ml).The clinical course of acute pancreatitis is strongly influenced by secondary cardiac, pulmonary and renal damage. The aim of the present study was to gather information about the compartment promoting the systemic damage. Therefore the activity of lipase, phospholipase A and plasmaprokallikrein and the concentration of tissue kallikrein and kininogen were measured in portal venous blood, pancreatic lymph and peritoneal exudate. Anaesthetized pigs were subjected to fluid resuscitation to keep systemic haemodynamic parameters constant. The pancreas was isolated in situ. The pigs were randomly assigned to a control group (n = 9) or one of the two pancreatitis groups (n = 10 each). Pancreatitis was induced by i.a. infusion of free fatty acid (FFS) or retrograde infusion of 5 % sodium taurocholate intraductally (NaT). In both pancreatitis groups the activity of lipase and phospholipase A increased. The most pronounced changes were seen in the peritoneal exsudate (phospholipase A activity 40 min after induction: control 10.0 U/1, NaT 72.2 U/1). In both pancreatitis groups there was evidence for activation of the tissue kallikreinkinin system in the form of an increase in the kallikrein concentration and a decrease in the kininogen concentration. Again the changes were most pronounced in the peritoneal exsudate (tissue kallikrein 40 min after induction: control 14.7 ng/ml, NaT 452 ng/ml)

Minnesota on the Map: A Historical Atlas

Review of: "Minnesota on the Map: A Historical Atlas," by David A. Lanegran

Minnesota on the Map: A Historical Atlas

Review of: "Minnesota on the Map: A Historical Atlas," by David A. Lanegran