Search results for "microcirculation"
showing 10 items of 319 documents
EpCAM and microvascular obstruction in patients with STEMI: a cardiac magnetic resonance study
2020
Abstract Introduction and objectives Microvascular obstruction (MVO) is negatively associated with cardiac structure and worse prognosis after ST-segment elevation myocardial infarction (STEMI). Epithelial cell adhesion molecule (EpCAM), involved in epithelium adhesion, is an understudied area in the MVO setting. We aimed to determine whether EpCAM is associated with the appearance of cardiac magnetic resonance (CMR)-derived MVO and long-term systolic function in reperfused STEMI. Methods We prospectively included 106 patients with a first STEMI treated with percutaneous coronary intervention, quantifying serum levels of EpCAM 24 hours postreperfusion. All patients underwent CMR imaging 1 w…
Hemodynamic Parameters Change Earlier Than Tissue Oxygen Tension in Hemorrhage
2010
BACKGROUND: Untreated hypovolemia results in impaired outcome. This study tests our hypothesis whether general hemodynamic parameters detect acute blood loss earlier than monitoring parameters of regional tissue beds. MATERIALS AND METHODS: Eight pigs (23-25 kg) were anesthetized and mechanically ventilated. A pulmonary artery catheter and an arterial catheter were inserted. Tissue oxygen tension was measured with Clark-type electrodes in the jejunal and colonic wall, in the liver, and subcutaneously. Jejunal microcirculation was assessed by laser Doppler flowmetry (LDF). Intravascular volume was optimized using difference in pulse pressure (dPP) to keep dPP below 13%. Sixty minutes after p…
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…
Dynamic MR imaging of breast lesions: correlation with microvessel distribution pattern and histologic characteristics of prognosis.
2006
To evaluate the association of dynamic enhancement parameters of benign and malignant breast lesions at magnetic resonance (MR) imaging with microvessel distribution and histologic prognostic tumor characteristics.Regional review board approval and informed consent were obtained. Surgical resection specimens of breast lesions (32 benign, 86 malignant) in 118 patients (age range, 28-86 years; mean, 58 years) who had undergone dynamic T1-weighted MR imaging of both breasts were included in the study. Different MR enhancement parameters and microvessel density (MVD) distribution were determined. In malignant lesions, TNM stage, tumor grade, proliferative activity, and hormone receptor expressi…
PLASMA PROTEIN LOSS DURING SURGERY: BENEFICIAL EFFECTS OF ALBUMIN SUBSTITUTION
2001
Plasma protein loss during abdominal surgery is a known phenomenon, but its possible pathophysiological relevance has remained unknown. The present study evaluates the effects of albumin substitution on systemic and local hemodynamics and cellular interactions in the mesenteric microcirculation. Rats underwent median laparotomy and exteriorization of an ileal loop for intravital microscopy of the mesenteric microcirculation. Plasma protein concentrations, systemic and local hemodynamics were recorded during the follow up period, with or without albumin substitution. Depending on the time course of plasma protein loss in control experiments, 80% of the calculated protein loss was infused dur…
Endothelial Cell Swelling and Brain Perfusion
1997
Background: Whereas the contribution of glial swelling to no-reflow conditions in the ischemic penumbra or during reperfusion after global ischemia is widely discussed, little is known about cell volume control of endothelial cells under reperfusion conditions. Methods: The effect of extracellular acidosis-a key mediator of secondary brain damage-on cell volume was studied in the GM7373 endothelial cell line. Experiments were performed at pH = 6.0 in the presence or absence of bicarbonate, and during exposure to inhibitors of specific transport systems such as ethyl isopropyl amiloride or 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid. Results: Endothelial swelling to 111.1 ± 3.4% was f…
Application of colour magnification technique for revealing skin microcirculation changes under regional anaesthetic input
2013
In this work the colour magnification technique was applied for monitoring of palm skin microcirculation changes under peripheral (Plexus Brachialis with axiliary access) Regional Anaesthesia (RA). During the RA procedure 20 minute video of patient’s forearm was taken at steady light conditions. Video content was processed offline by custom developed Matlab software with build-in colour magnification algorithm that performs temporal filtering of video sequence near-heartbeat frequency, spatial decomposition of video and amplification of pulsatile signal in every pixel of skin image. Using this method, we are able to visualize the subcutaneous microcirculation changes in high spatial resolut…
Direct Measurement of Reoxygenation in Malignant Mammary Tumors after a Single Large Dose of Irradiation
1984
Due to functional and morphological abnormalities of the terminal vascular bed in malignant tumors, a severe restriction of convective transport occurs even in very early growth stages. This leads to nutritional deprivation of the cancer cells and to unfavourable cellular microenvironments as well. During advanced tumor growth stages, the nutritional deprivation and the milieu conditions get worse because pronounced deterioration of diffusive transport is superimposed on the insufficient blood supply. This transport limitation is mainly caused by increases of intercapillary distances and by decreases of vascular surface areas per unit tissue volume. Moreover, these peculiarities of the tumo…
Regional cerebral blood flow and regional metabolism in cold induced oedema.
1973
24 hours following a cold induced oedema in cats rCBF was measured in the lesion area, the bluish stained cortex immediately adjacent to the lesion, a cortical area remote from the lesion, and in the contralateral uninjured hemisphere. Thereafter the brain was frozen and the respective tissue areas were removed and analyzed for water and electrolyte content as well as metabolite concentrations. It seems, that in the neighbourhood of a local lesion at least 3 different brain regions can be differentiated with regard to their characteristic pattern of data. In non-oedematous regions either hyperaemia or hypoaemia could be observed. In areas with local brain oedema rCBF was reduced inversely p…
Evaluation of labial microvessels in Sjogren syndrome: A videocapillaroscopic study
2008
Summary Sjogren's syndrome (SS) is a chronic autoimmune rheumatic disease characterized by a progressive lymphocytic infiltration of exocrine glands, especially salivary and lachrymal ones, leading to xerostomia, parotid gland enlargement, and xerophtalmia. SS may occur alone (primary) or in association with almost any of the autoimmune rheumatic diseases (secondary), the most frequent being rheumatoid arthritis. The aim of this study is to describe the capillaroscopic pattern of the labial mucosa in patients with SS. Methods A total of 20 patients affected by SS and 20 healthy controls were examined. The patients with conditions that compromise microcirculation, such as diabetes, hypertens…