Search results for "Circulation"
showing 10 items of 1137 documents
Margination of Fluorescent Polylactic Acid-Polyaspartamide based Nanoparticles in Microcapillaries In Vitro: the Effect of Hematocrit and Pressure.
2017
The last decade has seen the emergence of vascular-targeted drug delivery systems as a promising approach for the treatment of many diseases, such as cardiovascular diseases and cancer. In this field, one of the major challenges is carrier margination propensity (i.e., particle migration from blood flow to vessel walls); indeed, binding of these particles to targeted cells and tissues is only possible if there is direct carrier–wall interaction. Here, a microfluidic system mimicking the hydrodynamic conditions of human microcirculation in vitro is used to investigate the effect of red blood cells (RBCs) on a carrier margination in relation to RBC concentration (hematocrit) and pressure drop…
Influence of N-acetylcysteine on hepatic amino acid metabolism in patients undergoing orthotopic liver transplantation
2001
Experimental treatment with the antioxidant and glutathione precursor N-acetylcysteine (NAC) has been performed in orthotopic liver transplantation (OLT) to reduce reperfusion injury. To investigate the effect of NAC on the hepatic and intestinal amino acid metabolism, intraoperative amino acid exchange rates were studied in liver transplant recipients with high dose NAC treatment (n = 10) and in control patients (n = 9). Treatment with NAC was found to cause a loss of amino acids and increased urea nitrogen release from the liver graft. The net balance of most amino acids was shifted to increased hepatic release or decreased hepatic uptake. The initial cumulative splanchnic release of all …
Serum brain-derived neurotrophic factor and platelet activation evaluated by soluble P-selectin and soluble CD-40-ligand in patients with acute myoca…
2009
Little is known about the role of neurotrophins (NT) under adult vascular homeostasis in normal and pathological conditions. The NT family, including nerve growth factor and brain-derived neurotrophic factor (BDNF) are expressed in atherosclerotic vessels. Previous studies demonstrated that plasma BDNF levels were increased in the coronary circulation in patients with unstable angina. However, the role of BDNF during the onset and evolution of unstable angina remains to be elucidated. The objective of this study was to evaluate the relationship between BDNF, functional parameters and biological markers associated with inflammatory processes and platelet activation. BDNF serum levels were as…
Evaluation of the Oral Microcirculation in Patients Undergoing Anti COVID-19 Vaccination: A Preliminary Study
2022
Videocapillaroscopy allows the study of both the morphological and architectural structure of the microcirculation and its hemodynamic conditions; these parameters are directly involved in autoimmune and/or inflammatory pathologies. The purpose of this research, based on capillaroscopy, is to establish whether a patient who receives an anti-COVID 19 vaccine has any changes in their oral microcirculation. A complete capillaroscopic mapping of the oral cavity of the subjects examined was made; the investigated mucosa sites were the following: cheek, labial, chewing-gingival and back of the tongue. This study showed an increase in capillary density from the comparison between the mean labial c…
Topical capsaicin application and axon reflex vasodilatation of the tongue: A videocapillaroscopic study
2006
The aim of this study was to evaluate the effects of topical capsaicin application on human lingual mucosa and to assess if neurogenic inflammation might have a role in the pathogenesis of lingual diseases. Thirty patients (16 males and 14 females; mean age: 41.46 +/- 11.8 years; range: 23-60) were examined in our laboratory. The neurogenic inflammation was experimentally induced in the lingual mucosa close to 1) the left margin of the tongue and 2) the right margin of the tongue after ipsilateral nerve trunk anesthesia. The characteristics of lingual microcirculation were observed using computerized videocapillaroscopic techniques. The vasodilatation was observed close to the left margin o…
Computer simulation of oxygen tension histograms--a possibility for interpretation of microelectrode measurements.
1972
Mit Sauerstoff-Mikroelektroden werden die lokalen Werte des Sauerstoffpartialdruckes im Mikrobereich der Organe gemessen und graphisch als Haufigkeitsverteilungen (Histogramme) dargestellt. Theoretisch wird der Einfluss der Kapillaranordnung (Gleich-, Gegenstromsystem und Kapillarnetzwerk) auf die Haufigkeitsverteilung der P02 Werte untersucht. Die fur zweidimensionale Modelle durchgefuhrte Analyse zeigt, dass Unterschiede in der Durchblutung, wie sie in den einzelnen Zweigen der Kapillarnetzwerke auftreten, einen starken Einfluss auf die Histogramme haben.
Blasen-Stromuhr (bubble flow meter) mit Rohrelektroden und einem Me�wertumformer zur linearen Registrierung auf Direktschreibern
1961
Es wird eine Blasen-Stromuhr beschrieben, die an Stelle einer Photozelle ein Elektrodenpaar zur Anzeige des Blasendurchganges aufweist. Damit lassen sich auch optisch leichtdurchlassige Flussigkeiten messen. Die Impulse brauchen nur einstufig verstarkt zu werden, eine zweite Rohre erzeugt fur hohe Durchflusgeschwindigkeiten eine Wechselspannung zum Anlegen an die Meselektroden.
The active venous pulse in the wing circulation of bats (Chiroptera). A contribution to comparative angiology.
1978
Synthese, Verteilung und Ausscheidung von 14C markiertem 2-Phenyl-3-methyl-tetrahydro-1,4-oxazin (Preludin)
1958
A radioactive preludin preparation, C14 labelled on the 2-carbon of the tetrahydrooxazine ring, was injected into mice in doses of 100 mg/kg s.c. and rats in doses of 10 mg/kg i.v. The radioactivity of the tissues and excreta was followed for 48 hours. An activity concentration surpassing the average body concentration was obtained for a short time in the lungs and for a longer time in kidneys, liver and in the wall of stomach and small intestine. 95–99% of the total activity is found in the urine. The kidney excretion is virtually finished at the end of 8 hours; 1–5% appear after the 8th hour in faeces. No radioactivity was obtained from the expired CO2. The main excretion organs are kidne…
The significance of plasma kinins in intestinal obstruction and peritonitis
1969
The present concept of plasmakinin action suggests that they may also play an important role in the pathophysiology of intestinal obstruction and peritonitis. Since the assay of the kinins is still something of a problem, and since the percursor kallikrein can be determined by a standardized method, we studied the titers of kallikrein in the peripheral and portal circulation in dogs with experimental intestinal obstruction and in patients with these disorders. Significantly higher levels of kallikrein were found in intestinal obstruction, particularly in obstruction with strangulation (Fig. 1).