Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of variations of oxygen tension on the metabolism of bovine mesenteric arteries was studied in vitro. Glucose uptake, lactate production, glycogen content, adenosine triphosphate (ATP), creatine phosphate (CrP) and incorporation of [14C]leucine into protein were determined. The mesenteric arteries were suspended in Krebs-Henseleit bicarbonate buffer which was aerated with a gas mixture containing 5% CO2,O-95% O2 and N2 to 100%. Reduction of the O2 concentration of the gas phase from 95-20% resulted in little metabolic change. A further reduction from 20-0% O2 increased the lactate production 4-fold, indicating a marked Pasteur effect. At 0% O2 the glucose uptake was moderately increased and the glycogen content was decreased. The tissue level of CrP was reduced at a low oxygen tension and at 0% O2 the ATP content was also lowered. The incorporation of leucine into proteins was reduced at 0% O2.
Atherosclerosis
PMID:Influence of oxygen tension of the metabolism of vascular smooth muscle: demonstration of a Pasteur effect. 100 12

Free oxygen tension (pO2) and tissue blood flow (by the rate of elimination of hydrogen from the tissues after its single inhale) at rest and after functional stresses (oxygen inhalation, walking) were studied polarographically in healthy persons (10), patients with obliterating endarteritis (25) and obliterating atherosclerosis (22). It was shown that the rate of pO2 and capillary blood flow reduction in the tissues and peculiarities of their changes in response to functional stresses aid in establishing the precise differential diagnosis of obliterating endarteritis and atherosclerosis, a stage of the disease and also in evaluating the efficacy of treatment.
 ...
PMID:[Capillary blood flow and oxygen consumption in the leg muscles in obliterating endarteritis]. 101 88

Results of investigations into age-specific peculiarities inherent in the contractile function of the cardiac ventricular myocardium, hemodynamics of the lesser circulation, oxygen supply of the organism in young (6--12 months old) and old (3 1/2--4 1/2 year old) rabbits in normalcy and with experimental atherosclerosis are reported. The contractility of the left ventricle myocardium in old animals was down as compared to the normal in young ones. Induction of atherosclerosis impairs this important function of the myocardium to a still greater degree. In old animals hemodynamics of the lesser circulation is characterized by a rising systolic pressure in the right ventricle and of the tension-time index (TTI) as contrasted against the young one in normalcy and with atherosclerosis. Against this background an additional action on the organism is attended by more pronounced pathological manifestations, i.e. in reactions of the cardiovascular system (including the lesser circulation). The initial manifestations of hypoxia recorded in older animals, as compared to the younger ones in normality, become more intensive in cases of induced atherosclerosis. There is reduced consumption of oxygen, oxygen saturation of arterial and, especially, mixed venous blood, as well as oxygen tension in the arterial blood. The recorded changes are of significance in clarifying the caused and conditions conducive to the development of atherosclerosis and to the intensification of its manifestations in an old organism.
 ...
PMID:[Age-specific characteristics of functional disorders of the cardiovascular system and respiration in experimental atherosclerosis]. 102 20

In order to evaluate the sensibility and specificity of the maximal treadmill exercise-stress test, a correlation was made, in fifty patients, of the resus of the test and the findings at selective coronary arteriography. None of the patients had received cardioactive drugs previous to the study. Among twenty-nine patients with proven coronary disease, three had false negative exercise tests. The remaining twenty-six cases had positive tests. The sensitivity of the method (reliability in identifying the presence of disease) was 89.7%. Twelve of twenty-one subjects with normal coronary arteries had negative exercise tests. In eight patients without coronary artery lesions, the exercise test was positive (false positive tests). An additional patient had an equivocal response and is included among the false positive responses. These nine-patients form a special group since they had severe heart disease, even though it was not due to atherosclerosis of the major coronary vessels. The specificity of the test (reliability in identifying the absence of disease) was 57.1%. However, in the absence of other heart disease, none of the subjects with normal coronary arteries had a false positive response. An analysis is made of the possible causes of these false negative and false positive responses. It was also shown in this study that the patients with coronary artery disease and positive treadmill tests had a definite functional aerobic impairment as well as a significant reduction in such indices of myocardial oxygen consumption as the heart rate and the double product (pressure-pulse), when compared to the subjects with normal coronary vessels and negative tests. In the group of patients with false positive responses, these parameters were not significantly different from the normals. The exercise-stress test protocol used in this study appears to have an adequate sensibility and an acceptable specificity.
 ...
PMID:[Correlation between exercise test and coronariography]. 102 29

The following effects in treatment of coronary artery disease are desired: 1. Elimination or improvement of angina. 2. Improvement of physical capacity. 3. Prevention of imminent complications (myocardial infarct, cardiac arrhythmias, heart failure, embolism). 4. Elimination or diminuation of risk factors. 5. Prolongation of life. - In a critical survey concerning long-term studies of patients with aorto-coronary bypass or medical treatment in the literature subtile lists of indications for surgical and conservative treatment are put up (Table II and III), illustrated by case reports. - Useful criteria for diagnosis, follow-up, and prognosis are selective coronary angiography, ventriculography as well as determination of the coronary reserve (Argon Method). Indication for aorto-coronary bypass and resection of myocardial aneurysms are presented. Principles of medical treatment are: 1. Diminuation of myocardial oxygen requirement (release of pressure, economisation of work load, recompensation, regulation of arrhythmias) and 2. improvement of myocardial oxygen supply (Diminuation of coronary perfusion resistance including prevention and treatment of atherosclerosis). Indication for various medications are discussed (nitrites, beta-adrenergic blocking agents and antihypertensive drugs, glycosides, medication for arrhythmias, coronary dilatators, anticoagulants, and lipotropic substances). Their mode of action is debated and documented by own results. Present possibilities and limits in treatment of coronary artery disease are presented.
 ...
PMID:[Indications for surgical and medical treatment of coronary artery disease (author's transl)]. 108 41

The local oxygen pressure of muscle tissue was measured in 10 patients with occlusive atherosclerosis and in 9 healthy volunteers using a micro-Pt-electrode. In 3 cases, the muscular pO2 values of an ischemic leg were compared to the non-ischemic leg of the same patient. In both groups, there was a statistically significant difference in the oxygen pressure of the muscle tissue in normal legs of volunteers as compared to the ischemic legs. Measurements of the local oxygen pressure in the muscle enables us to have a quantitative measure for the ischemic situtation. It is a useful diagnostic method in patients suffering from ischemic claudication and seems to be an objective criterium of therapeutical methods.
 ...
PMID:[Oxygen pressure values in the ischemic muscle tissue of patients with occlusive arterial diseases (author's transl)]. 121 82

The author describes the histological and ultrastructural manifestations of the reactions of the arterial wall after experimental damage and the phases, through which the process of repair passed. After the initial response the standard hemostatic and inflammatory reaction in all cases occurred substitution of the damaged areas of the arterial wall and regeneration of the involved cellular components of the arterial tissue, which caused repair of its integrity. The repair reaction was manifested with proliferation of smooth muscle cells in the subendothelial area of the damaged artery and with abundant accumulation of the connective tissue martrix, which after some period of time caused formation of the so called intimal thickening. In cases with many massive intimal thickenings there were disturbances in the transparietal diffusion of oxygen and nutritive substances, which affected favourably the penetration of serum lipoproteins in the arterial wall and facilated for the development of atherosclerosis in the zones of the preceding arterial damage.
 ...
PMID:[Reaction to injury and recovery in the arterial wall]. 122 2

Standard and submaximal physical load tests were contrasted in studying the functional state of the cardio-respiratory system in healthy individuals and in patients with coronary atherosclerosis, post-infarction cardiosclerosis, mitral lesions and cardiac-pulmonary insufficiency. The application of physical load tests of different types is shown to be instrumental in obtaining a mutually complementary information about the function of the cardiac-respiratory system and the degree of pulmonary and cardiac decompensation. The authors attach great importance to determining the ratio of an actual oxygen uptake to its proper values and suggest using this indicator, called by them performance capacity index, in quantitative appraisal of physical capacity to perform work. In recognizing early stages of circulatory insufficiency of considerable interest is determining the ratio of the venous blood concentration of lactate, pyruvate and some other biochemical factors to the amount of work done.
 ...
PMID:[Early diagnosis of cardiac insufficiency with the spiroergometric method]. 123 18

Hyperhomocysteinemia is a risk factor for atherosclerosis, and is found in the heterozygous form in approximately one-third of all individuals with coronary artery disease. The sulfhydryl group of homocysteine has been viewed as contributing to the atherogenic effects of this low-molecular-weight thiol, largely as a consequence of facilitating the generation of hydrogen peroxide from oxygen. Hydrogen peroxide, in turn, is presumed to induce dysfunction and damage to the endothelial cell, leading to attenuation of its antithrombotic and vasodilatory properties. As we have shown that endothelium-derived relaxing factor (EDRF) and other oxides of nitrogen can form adducts with thiols, we hypothesized that EDRF released from normal endothelium S-nitrosates homocysteine, rendering it nontoxic to the endothelium. We show that EDRF released from endothelial cells in the presence of homocysteine can lead to the formation of S-nitrosohomocysteine; that, like other S-nitrosothiols, S-nitrosohomocysteine induces vasorelaxation and platelet inhibition; and that, in contrast to homocysteine, S-nitrosohomocysteine does not support hydrogen peroxide generation and does not lead to endothelial dysfunction. These data suggest that normal endothelial cells modulate the adverse effects of homocysteine by facilitating the formation of the EDRF adduct, S-nitrosohomocysteine. The toxic effects of homocysteine may, then, result from an inability of the endothelium to sustain adequate production of EDRF in the face of elevated homocysteine concentration.
 ...
PMID:Endothelium-derived relaxing factor modulates the atherothrombogenic effects of homocysteine. 128 70

Since the seventies, and in particular the eighties of this century, findings on pathogenetic mechanisms of ischaemic heart disease are expanding markedly and are becoming more accurate. This makes it possible to know and understand better factors which influence the genesis and development of myocardial ischaemia including the most serious clinical forms (unstable angina pectoris, acute myocardial infarction and sudden cardiac death). Diminution of the cardiac flow and/or increased oxygen demands of the heart muscle are not the only determinants of myocardial ischaemia which is influenced markedly also by neurohumoral, metabolic, prothrombotic (proaggregation and procoagulation) factors as well as antithrombotic and haemodynamic factors. Acute coronary syndromes have as a rule, in particular in patients with out severe atherosclerotic stenosis of the coronary arteries, a common pathophysiological mechanism of fissuration of the atherosclerotic plaque followed by different grades of dynamic coronary occlusion depending on vasoconstriction--spasm of the coronary arteries and thrombus formation. The coronary arteries, usually affected with atherosclerosis, may be due to the comprehensive action of various factors temporarily, intermittently or permanently occluded. In case of the development of acute coronary syndromes thrombosis plays a key role. Better knowledge of pathogenetic mechanism of IHD markedly changes views on treatment and management of patients with IHD in particular patients with acute coronary syndromes. The authors emphasize strategies focused (also preventively) on preventing progression of the disease with the aim to improve survival and the short-term and long-term prognosis.
 ...
PMID:[Pathogenesis of myocardial ischemia and acute coronary syndromes]. 129 43


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>