Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study reports the development and characterization of a murine model of right ventricular dysfunction following graded constriction in the pulmonary artery via microsurgical approaches. To analyze in vivo ventricular function, a technique of x-ray contrast microangiography was developed to allow the quantitative analysis of ventricular volumes and of ejection fraction in normal and pressure-overloaded right ventricle. Severe, chronic pulmonary arterial banding for 14 days resulted in right ventricular dilatation and dysfunction, associated with right atrial enlargement, and angiographic evidence of tricuspid regurgitation. These effects were dependent on the extent of hemodynamic overload, since more moderate pulmonary arterial constriction resulted in hypertrophy with maintenance of right ventricular function. With severe pulmonary artery constriction, the murine right ventricle displays a failing heart phenotype including chamber dilation with reduced function that resembles right ventricular dysfunction in man during chronic pulmonary arterial hypertension. Northern and immunoblot analyses demonstrate a marked down-regulation of phospholamban mRNA and its corresponding protein with both levels of constriction, while a less pronounced but significant depression of sarcoplasmic reticulum Ca(2+)-ATPase protein was observed with severe overload, suggesting that this pattern is an early genetic marker of ventricular dysfunction. By coupling mouse genetics with this murine model and the ability to assess cardiac function in vivo, one should be able to test the role of the down-regulation of phospholamban and other defined alterations in the cardiac muscle gene program in the onset of the failing heart phenotype.
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PMID:Molecular and physiological alterations in murine ventricular dysfunction. 814 76

To contribute for making early diagnosis and treatment of acute pulmonary embolism (APE), we investigated on clinical pictures of 225 patients with APE. Common underlying factors were heart disease, prolonged bed rest, post-surgical state, thrombophlebitis, malignant tumor and post-catheterization state in this order. Dyspnea, chest pain, tachycardia and shock were frequently seen as initial symptoms and signs. Blood screening showed leukocytosis, hypoxemia, hypocapnia and elevated serum LDH. Electrocardiographic findings highly demonstrated were ST.T abnormalities, such as T inversion with ST elevation in V1-3, ST depression in V4-6 and sinus tachycardia. Chest X-rays showed diminished pulmonary vascular marking and pulmonary artery dilation. Right ventricular dilatation were frequently seen on 2-dimensional echocardiograms. Pulmonary artery pressure were elevated up to 49/20 (30) mmHg. Twenty-five percent of the patients died, and the recurrence was seen in 4%. Thus, as soon as APE is suspected by above clinical findings, definitive diagnosis should be obtained by the lung perfusion scan and pulmonary arteriography, then oxygen and thrombolytic agents should be given immediately to prevent the fatal outcome.
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PMID:[Early diagnosis and management of acute pulmonary embolism: clinical evaluation those of 225 cases]. 835 37

Changes of ischemic myocardium following coronary occlusion, including active and passive functions, and adaptive changes of non-ischemic surviving myocardium have been summarized under the term "left ventricular remodeling" post myocardial infarction. An increase in left ventricular volume may be a consequence, and associated with an adverse prognosis. Although left ventricular dilatation may increase stroke volume and, thus, be compensatory at first, in about one-fifth of patients it ultimately results in progressive dysfunction and heart failure. Major determinants of this process are time, infarct size, infarct location, global left ventricular function assessed 4 days after infarction by radionuclide ejection fraction and right heart catheter (stroke volume), and morphology of the infarct-associated coronary artery. The surviving myocardium hypertrophies and may also dilate structurally. Depression of left ventricular ejection fraction chronically after the infarct is due to deterioration of wall motion of chamber segments initially classified normal by radionuclide analysis. Biochemical changes may also occur, including reduction of phosphocreatine, prolongation of time to peak Cai2+, and changes in myosin isoforms. Systemic or local humoral factors may be involved in these changes, however, clear evidence is still lacking. Perfusion of surviving myocardium may be altered under various conditions due to morphologic and functional changes of coronary vasculature. Successful prevention of heart failure and death by angiotensin converting enzyme inhibitors in asymptomatic patients with left ventricular dysfunction post-myocardial infarction has supported the pathophysiologic concepts of remodeling.
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PMID:Ventricular remodeling after myocardial infarction. Experimental and clinical studies. 835 28

Broiler chicks in different groups were fed furazolidone (0, 400 and 800 mg/kg feed) and sodium chloride (500 and 1510 mg/kg feed) separately and concurrently from 1 to 30 days of age. Furazolidone (Fz) induced ascites, leg weakness, convulsions, depression and mortality was exacerbated by concurrent feeding of 1510 mg NaCl. Hemorrhages in the liver, swollen kidneys, pallor of the kidneys and cystic testes were present in all birds fed furazolidone either alone or in combination with NaCl. However, at microscopic level, necrotic changes were observed in the liver and kidneys of birds fed NaCl only. Fz-induced cardiac ventricular dilatation and thinning of walls were more severe when 400 mg Fz was fed concurrently with 1510 mg NaCl but feeding of 800 mg Fz with the same level of NaCl resulted in partial amelioration of cardiac changes. It is suggested that high dietary NaCl may exacerbate and alter the clinical and morphological picture of Fz toxicosis.
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PMID:Effect of concurrent feeding of furazolidone and sodium chloride upon some clinical, pathological and cardiac morphometric parameters in broiler chicks. 859 92

Spontaneously hypertensive rats (SHR) of advanced age exhibit depressed myocardial contractile function and ventricular fibrosis, as stable compensated hypertrophy progresses to heart failure. Transition to heart failure in SHR aged 18-24 months was characterized by impaired left ventricular (LV) function, ventricular dilatation, and reduced ejection fraction without an increase in LV mass. Studies of papillary muscles from SHR with failing hearts (SHR-F), SHR without failure (SHR-NF), and age-matched Wistar Kyoto (WKY) rats allowed examination of changes in the mechanical properties of myocardium during the transition to heart failure. Papillary muscles of SHR-F exhibited increased fibrosis, impaired contraction, and decreased myocyte fractional area. These findings in papillary muscles were correlated with a higher concentration of hydroxyproline and increased histological evidence of fibrosis in the LV free wall. While a depression in active tension accompanied these structural alterations in papillary muscles, it was not evident when active tension was normalized to myocyte fractional area. Together, these data suggest that individual myocyte function may be preserved but that myocyte loss and replacement by extracellular matrix contribute substantially to the decrement in active tension. An absent or negative inotropic response to isoproterenol is observed in SHR-F and SHR-NF papillary muscles and may result in part from age-related alterations in beta-adrenergic receptor dynamics and a shift from alpha- to beta-myosin heavy chain (MHC) protein. During the transition to failure, ventricles of SHR exhibit a marked increase in collagen and fibronectin mRNA levels, suggesting that an increase in the expression of specific extracellular matrix genes may contribute to fibrosis, tissue stiffness, and impaired function. Transforming growth factor-beta 1 (TGF-beta 1) mRNA levels also increase in SHR-F, consistent with the concept that TGF-beta 1 plays a key regulatory role in remodelling of the extracellular matrix gene during the transition to failure. The renin-angiotensin-aldosterone system is also implicated in the transition to failure: SHR treated with the angiotensin converting enzyme inhibitor captopril starting at 12 months of age did not develop heart failure during the 18-24 month observation period. Captopril treatment that was initiated after rats were identified with evidence of failure led to a reappearance of alpha-MHC mRNA but did not improve papillary muscle function. Research opportunities include investigation of apoptosis as a mechanism of cell loss, delineation of the regulatory roles of TGF-beta 1 and the renin-angiotensin-aldosterone system in matrix accumulation, and studies of proteinase cascades that regulate matrix remodelling.
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PMID:The ageing spontaneously hypertensive rat as a model of the transition from stable compensated hypertrophy to heart failure. 868 57

Electrocardiographic (ECG) findings of pulmonary embolism (PE) include S1Q3T3 pattern, right bundle-branch block, right-axis deviation, and T-wave inversion in medial precordial leads. We report other uncommon ECG changes associated with various symptoms during recurrent PE as documented by computed tomography (CT) scans in a single patients. An 83-year-old woman was admitted with PE secondary to deep venous thrombosis in the left leg. During episodes of chest pain, ECG showed QTc prolongation (480 ms) with new T-wave inversion in leads III, aVF, and V1-V3, and ST-segment depression in leads V5-V6. Despite adequate anticoagulant therapy, recurrent episodes of PE occurred in the hospital. When the patient experienced sudden chest tightness, ECG showed a new S-wave notch in lead V1 and clock-wise rotation with sinus tachycardia. She also experienced transient syncope with hypotension. At this time, ECG showed transient atrioventricular junctional rhythm followed by sinus arrest, and CT scan showed a new massive embolus in the main pulmonary trunk with right ventricular dilatation, as demonstrated by echocardiography. The mechanism responsible for QTc prolongation with ST-T changes, the S-wave notch in lead V1 with clockwise rotation, or atrioventricular junctional rhythm with sinus arrest during PE may be associated with myocardial ischemia, acute right ventricular overload, or vagal reflex, respectively.
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PMID:Uncommon electrocardiographic changes corresponding to symptoms during recurrent pulmonary embolism as documented by computed tomography scans. 982 4

Dilated cardiomyopathy (DCM) is a myocardial disease characterized by progressive depression of myocardial contractile function and by ventricular dilatation. Abnormalities of the cellular and humoral immune system are present in patients with myocarditis and DCM. Various circulating cardiac autoantibodies have been detected among patients suffering from DCM. The relative contribution of cardiac antibodies to cardiac malfunction in DCM remains to be elucidated. Extraction of antibodies by immunoadsorption has been successfully used for treatment of various autoimmune diseases. In this review we report recent studies, which indicate that immunoadsorption improves cardiac function of patients with DCM. The data from these studies indicate that activation of the humoral immune system, with production of cardiac autoantibodies, may play a functional role in cardiac malfunction of patients with DCM.
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PMID:Improvement of cardiac function after immunoadsorption in patients with dilated cardiomyopathy. 1190 80

The role of inducible nitric-oxide synthase (iNOS) in the pathogenesis of heart failure is still a matter of controversy. In contrast to early reports favoring a contribution of iNOS because of the negative inotropic and apoptotic potential of NO, more recent clinical and experimental data question a causative role. Here we report that transgenic mice with cardiac specific iNOS-overexpression and concomitant myoglobin-deficiency (tg-iNOS+/myo-/-) develop signs of heart failure with cardiac hypertrophy, ventricular dilatation, and interstitial fibrosis. In addition, reactivation of the fetal gene expression program typical for heart failure occurs. The structural and molecular changes are accompanied by functional depression such as reduced contractility, ejection fraction, and cardiac energetics. Our findings indicate that excessive cardiac NO formation can cause heart failure; however, under normal circumstances myoglobin constitutes the important barrier that efficiently protects the heart from nitrosative stress.
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PMID:Myoglobin protects the heart from inducible nitric-oxide synthase (iNOS)-mediated nitrosative stress. 1266 3

A forty-one-year-old male, with no risk factors for coronary artery disease (CAD) and with moderate alcohol intake, was admitted in 1992 to Portalegre Hospital with heart failure due to viral cardiomyopathy. He was re-admitted in 1998 with acute pulmonary edema and was put on mechanical ventilation for 48 hours, and transferred to Pulido Valente Hospital when stable. The physical exam was without abnormalities. ECG showed first degree AV block, left ventricular hypertrophy and 2 mm ST depression in the precordial leads. The echocardiogram revealed left ventricular dilatation and depressed systolic function. Coronary angiography showed single-vessel CAD and coronary artery anomaly. Dobutamine stress echocardiography was halted due to hypertension, making it impossible to evaluate ischemic response. Holter monitoring showed five-complex ventricular tachycardia. The patient was discharged medicated with amiodarone, with indication for cardiac scintigraphy and electrophysiological study.
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PMID:Left main coronary artery originating in the right sinus of Valsalva. 1500 65

Several experimental studies have shown that levocarnitine reduces myocardial injury after ischemia and reperfusion by counteracting the toxic effect of high levels of free fatty acids, which occur in ischemia, and by improving carbohydrate metabolism. In addition to increasing the rate of fatty acid transport into mitochondria, levocarnitine reduces the intramitochondrial ratio of acetyl-CoA to free CoA, thus stimulating the activity of pyruvate dehydrogenase and increasing the oxidation of pyruvate. Supplementation of the myocardium with levocarnitine results in an increased tissue carnitine content, a prevention of the loss of high-energy phosphate stores, ischemic injury, and improved heart recovery on reperfusion. Clinically, levocarnitine has been shown to have anti-ischemic properties. In small short-term studies, levocarnitine acts as an antianginal agent that reduces ST segment depression and left ventricular end-diastolic pressure. These short-term studies also show that levocarnitine releases the lactate of coronary artery disease patients subjected to either exercise testing or atrial pacing. These cardioprotective effects have been confirmed during aortocoronary bypass grafting and acute myocardial infarction. In a randomized multicenter trial performed on 472 patients, levocarnitine treatment (9 g/day by intravenous infusion for 5 initial days and 6 g/day orally for the next 12 months), when initiated early after acute myocardial infarction, attenuated left ventricular dilatation and prevented ventricular remodeling. In treated patients, there was a trend towards a reduction in the combined incidence of death and CHF after discharge. Levocarnitine could improve ischemia and reperfusion by (1) preventing the accumulation of long-chain acyl-CoA, which facilitates the production of free radicals by damaged mitochondria; (2) improving repair mechanisms for oxidative-induced damage to membrane phospholipids; (3) inhibiting malignancy arrhythmias because of accumulation within the myocardium of long-chain acyl-CoA; and (4) reducing the ischemia-induced apoptosis and the consequent remodeling of the left ventricle. Propionyl-L-carnitine is a carnitine derivative that has a high affinity for muscular carnitine transferase, and it increases cellular carnitine content, thereby allowing free fatty acid transport into the mitochondria. Moreover, propionyl-L-carnitine stimulates a better efficiency of the Krebs cycle during hypoxia by providing it with a very easily usable substrate, propionate, which is rapidly transformed into succinate without energy consumption (anaplerotic pathway). Alone, propionate cannot be administered to patients in view of its toxicity. The results of phase-2 studies in chronic heart failure patients showed that long-term oral treatment with propionyl-L-carnitine improves maximum exercise duration and maximum oxygen consumption over placebo and indicated a specific propionyl-L-carnitine effect on peripheral muscle metabolism. A multicenter trial on 537 patients showed that propionyl-L-carnitine improves exercise capacity in patients with heart failure, but preserved cardiac function.
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PMID:Therapeutic effects of L-carnitine and propionyl-L-carnitine on cardiovascular diseases: a review. 1559 Oct 5


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