Search results for "Microcirculation"
showing 10 items of 319 documents
Atrial fibrillation is associated with cardiac hypoxia.
2008
BACKGROUND: Atrial fibrillation (AF), the most common human arrhythmia, is responsible for substantial morbidity and mortality and may be promoted by selective atrial ischemia and atrial fibrosis. Consequently, we investigated markers for hypoxia and angiogenesis in AF. METHODS: Right atrial appendages (n=158) were grouped according to heart rhythm [sinus rhythm (SR) or AF]. The degree of fibrosis and microvessel density of all patients were determined morphometrically using Sirius-Red- and CD34/CD105-stained sections, respectively. Next, sections (n=77) underwent immunostaining to detect hypoxia- and angiogenesis-related proteins [hypoxia-inducible factor (HIF)1 alpha, HIF2 alpha, vascular…
Expression of thrombospondin-1 in pancreatic carcinoma: correlation with microvessel density.
2001
Thrombospondin-1 (TSP-1) is a multifunctional platelet and extracellular matrix protein that is involved in angiogenesis. Under certain pathological conditions, e.g., malignant tumors, high concentrations of TSP-1 work as an angiogenic agonist. Here we examined 98 pancreatic carcinomas with respect to TSP-1 immunoreactivity and its correlation to intratumoral microvessel density (MVD), a representation of the overall degree of angiogenesis in carcinomas. Northern blot analysis for TSP-1 mRNA was performed in seven additional cases. Eighty-seven tumors showed strong TSP-1 immunoreactivity, nine carcinomas were only weakly positive, and two lesions were negative for TSP-1. TSP-1 immunoreactiv…
Acute effects of three isoflavone class phytoestrogens and a mycoestrogen on cerebral microcirculation.
2007
Phytoestrogens and mycoestrogens are naturally occurring plant and fungus secondary metabolites with estrogen-like structure and/or actions. We aimed to check the hypothesis that phytoestrogens and mycoestrogens, due to their ability to elicit cerebral vasodilation, can induce acute increases in brain blood perfusion. For this purpose, we continuously recorded cerebrocortical perfusion by laser-Doppler flowmetry in anesthetized rats receiving intracarotid infusions (1 mg/kg) of one of the following estrogenic compounds: biochanin A, daidzein, genistein or zearalanone. We have shown the ability of two isoflavone class phytoestrogens (daidzein and biochanin A) and the mycoestrogen zearalanone…
[Oral capillaroscopy: a new diagnostic method].
2011
The morphological-functional study of microcirculation is of fundamental importance; in fact, the microvascular bed is directly involved both in autoimmune etiopathogenesis pathologies, and in acute and chronic inflammatory etiopathogenesis pathologies. Oral capillaroscopy is a very stimulating method for studying microcirculation, because of the possibility of studying small vessels in vivo by means of a microscope. Today, it is becoming more reliable thanks to the improvement of the observation tools (photography, videomicroscopy).
Burning mouth syndrome: is acupuncture a therapeutic possibility?
2010
Burning mouth syndrome is a chronic pathology of unknown ethiopathogenesis. The aim of this study was to evaluate whether acupuncture can produce a reduction of the burning sensation by influencing the oral microcirculation. METHODS: Thirty patients (10 male and 20 female; mean age +/- SD = 65.4 +/- 2.17) and 30 healthy subjects (10 male and 20 female; mean age +/- SD = 62.06 +/- 6.72) were recruited for the study. The patients were treated with acupunctural techniques based on traditional Chinese medicine. Microcirculation was observed in vivo using videocapillaroscopy at three different times: t(0)) in the absence of acupuncture; t(1)) 1 minute after the insertion of the needles; and t(2)…
Predictors of microvascular complications in type 1 diabetic patients at onset: The role of metabolic memory
2011
Background Several epidemiological studies showed a close association between metabolic control and microvascular complications in type 1 Diabetes Mellitus (T1DM). The aim of our longitudinal observational study was to evaluate the predictive role of the main clinical and biochemical parameters in determining microvascular complications. Methods 376 T1DM patients, hospitalized in our division from 1991 to 2005 (mean follow-up = 10.93 ± 4.26 years) were studied. Stepwise Cox regression analysis was used to identify the influence of residual ß-cell function, ß-cell autoimmunity, HbA1c levels and other clinical and laboratory parameters in the development of microalbuminuria and retinopathy. R…
CXCR2 blockade impairs angiotensin II-induced CC chemokine synthesis and mononuclear leukocyte infiltration.
2007
Objective—Angiotensin II (Ang-II) and mononuclear leukocytes are involved in atherosclerosis. This study reports the inhibition of Ang-II–induced mononuclear cell recruitment by CXCR2 antagonism and the mechanisms involved.Methods and Results—Ang-II (1 nmol/L, i.p. in rats) induced CXC and CC chemokines, followed by neutrophil and mononuclear cell recruitment. Administration of the CXCR2 antagonist, SB-517785-M, inhibited the infiltration of both neutrophils (98%) and mononuclear cells (60%). SB-517785-M had no effect on the increase in CXC chemokine levels but reduced MCP-1, RANTES, and MIP-1α release by 66%, 63%, and 80%, respectively. Intravital microscopy showed that pretreatment with S…
Disturbance of hepatic and intestinal microcirculation in experimental liver cirrhosis
2005
AIM: To analyze hepatic, mesenteric and mucosal microcirculation and leukocyte-endothelium interaction (LEI) in a rat model with liver cirrhosis. METHODS: Hepatic cirrhosis was induced in Wistar rats by gavage with carbon tetrachloride, and intravital videomicroscopy was performed in liver, mesentery and small intestine mucosa. Special emphasis is given on microcirculatory and morphometric changes during cirrhotic portal hypertension. RESULTS: LEI was influenced significantly in the cirrhotic liver but not in the gut. Blood flow measurement showed significant differences among liver, main mesenteric vessels and the mucosa. The results of our study indicate that liver cirrhosis leads to alte…
The association between coronary microvascular dysfunction and carotid intima media thickness in patients with cardiac syndrome X
2016
Abstract Objective The aim of this study was to evaluate in patients with cardiac syndrome X (CSX), using validated angiography indices, coronary blood flow and myocardial perfusion of the microcirculation to assess whether there is greater microvascular dysfunction in patients with increase of carotid intima media thickness (C-IMT), compared to those who do not have. Methods Our study was performed on a population 124 patients with CSX that underwent coronary angiography and carotid ultrasound. We divided the sample into two categories: patients with increase of C-IMT and those without increase. We calculated Gibson and Yusuf indices for each patient based on angiographic images, including…
Elevation of plasma viscosity induces sustained NO-mediated dilation in the hamster cremaster microcirculation in vivo
1997
We studied whether a flow-independent increase of luminal wall shear stress (WSS) could dilate hamster arterioles in vivo and which endothelial mediators are potentially involved. To this end the plasma viscosity was elevated by exchanging blood for dextran-erythrocyte solution thereby augmenting WSS. Diameters of small and large arterioles as well as red blood cell velocities were measured before and after exchange of blood for solutions of identical haematocrit containing either high- (HMWD) or low-molecular weight dextran (LMWD). The potential role of endothelial autacoids was investigated by local application of the NO-synthase inhibitor NG-nitro-L-arginine (L-NNA), the inhibitor of cyc…