Search results for "Perfusion"

Macular capillary perfusion density and macular vessel density in open‐angle glaucoma and ocular hypertension: a quantitative study using optical coh…

2021

Targeting antioxidants to mitochondria: a potential new therapeutic strategy for cardiovascular diseases.

2007

Mitochondria produce large amounts of free radicals and play an important role in the life and death of a cell. Thus, mitochondrial oxidative damage and dysfunction contribute to a number of cell pathologies that manifest themselves through a range of conditions including ischemia-reperfusion injury, sepsis, diabetes, atherosclerosis and, consequently, cardiovascular diseases (CVD). In fact, endothelial dysfunction, characterized by a loss of nitric oxide (NO) bioactivity, occurs early on in the development of atherosclerosis, and determines future vascular complications. Although the molecular mechanisms responsible for mitochondria-mediated disease processes are not yet clear, oxidative s…

Ozone therapy in idiopathic carpal tunnel syndrome. Biochemical, neurophysiological and clinical aspects

2018

Purpose.
 Idiopathic Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy; however few and only retrospective studies have been found in search engines about Ozone Therapy. 
 The aim of this paper was to evaluate clinical and neurophysiological outcome following Ozone Therapy in CTS.
 We focused the attention on the evidences concerning the role of Subsynovial Connective Tissue (SSCT) in the pathogenesis of CTS and the ozone pre-conditioning effects linked to pain and inflammatory pathways and to fibrosis induced by Ischemia-Reperfusion Injury.
 
 Materials and methods.
 Thirty-five patients, aged between 21 and 80, were stratified clinically b…

Changes of Oxygen Supply to the Tissue Following Intravenous Application of Anesthetic Drugs

1973

The main function of the clinical anesthiologist is to make surgical treatment painless for the patient. For this purpose he uses drugs that severely interfere with the regulation of oxygen supply to the tissue. The same problem exists for the scientists working on animal experiments where he has to decide whether his experimental results were not changed by the anesthiological treatment.

Peritumoral perfusion and proton spectroscopic MR imaging in the differentiation of gliomas and solitary metastases

2015

Purpose: To asses the value of peritumoural perfusion-weighted and proton spectroscopic MR imaging in preoperative grading of gliomas and in differentiating between primary gliomas and solitary metastases. Methods and Materials: Ten low-grade gliomas, eight high-grade gliomas, and ten metastases were prospectively evaluated with MR imaging, dynamic susceptibility contrast-enhanced perfusion imaging, and single-voxel proton MR spectroscopy before surgical resection or stereotactic biopsy. Maximal rCBV values and maximal Cho/Cr ratios were calculated from peritumoural region surrounding the tumour. Tumour grade presumed with these values was compared to histopathologic grading. Differences in…

An economical hemoperfusion system to determine in vitro clearances of various poisons with different adsorbents.

1980

An economical hemoperfusion system for clearance studies in vitro was developped. It was ascertained, that hemoperfusion using columns which contain 13 g of adsorbent and perfused at a blood flow rate of 1.25 ml/min results in the same relative clearances as when using clinical sized columns containing 300–355 g of the absorbent and run at 100 ml/min. The adsorption kinetics of toxicologically important drugs and pesticides are given as examples. To date 27 substances were tested systematically. The investigation has shown, that no adsorbent is without exception the best one, but the efficacy can vary from substance to substance.

Infarct Size Measurement by Triphenyltetrazolium Chloride StainingVersus In VivoInjection of Propidium Iodide

1997

Infarct size delineation by triphenyltetrazolium chloride (TTC) staining is dependent on sufficient reperfusion. We therefore evaluated the possibility of using propidium iodide (PI), a reagent conventionally used in flow cytometry to fluorescently stain dead cells, for infarct size analysis after short periods of reperfusion. Forty-five rabbits were subjected to either 15 min, 2 h or 4.5 h of coronary artery occlusion without reperfusion, or to 15 min, 30 min and 2 h of coronary artery occlusion followed by 30 min, 1 h and 3 h of reperfusion. Fifteen min before terminating the experiment, PI was injected into the left atrium. Patent blue violet was used to delineate the area at risk. Follo…

Microvascular in vivo assessment of reperfusion injury: significance of prostaglandin E1 and I2 in postischemic “no-reflow” and “reflow-paradox”

2004

Microvascular ischemia-reperfusion (I/R) injury is characterized by failure of capillary perfusion ("no-reflow") and reoxygenation-associated phenomena ("reflow-paradox"), including activation of leukocyte-endothelium interaction with cytotoxic mediator-induced loss of endothelial integrity. The objectives of this study were to elucidate the impact of both prostaglandins E(1) (PGE(1)) and I(2) (PGI(2)) in microvascular reperfusion injury, with special focus on the distinct pathophysiology of no-reflow- and reflow-paradox phenomena.By use of the hamster dorsal skinfold preparation and in vivo fluorescence microscopy, the microcirculation of a striated skin muscle was assessed before 4 h of p…

Possible roles of nitric oxide in the physiology and pathophysiology of the guinea pig cochlea.

2000

Two nitric oxide synthase isoforms (NOS-I and NOS-III) are present in the mammalian cochlea, and many regulatory functions of the inner ear could be mediated by NO. In this study, cochlear potentials and immunohistochemical measures were analyzed by changing the concentration of NO in the guinea pig during intracochlear and intravenous application of an NOS inhibitor and an NO donor. In anesthetized guinea pigs the NOS inhibitor NG-nitro-L-arginine-methylester (L-NAME) was applied by intracochlear perfusion or intravenously. The cochlear potentials and blood pressure were measured during and after the application. Cochleae were removed and prepared for morphological and immunohistochemical …

Use of photoplethysmography to determine gastrointestinal perfusion pressure: an experimental canine model.

2002

<i>Objectives:</i> To develop an experimental model to assess the parietal perfusion pressure (PPP) of the digestive tract using photoplethysmography. <i>Materials and Methods:</i> Twenty-two mongrel dogs were used. Progressive external compression was applied to the intestinal wall and the PPP was assessed with photoplethysmography. The study group was divided into two groups. In group 1 PPP was measured at the levels of the stomach, duodenum, jejunum and transverse colon. In group 2 PPP was measured after temporary occlusion of the truncal and marginal circulation of the jejunum to provide further variables. <i>Results:</i> The PPP decreased significant…