Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Examination by light and electron microscopy of human myocardium from necropsies and biopsy specimens has revealed evidence that mitochondria can be transformed into granules of lipofuscin. This pigment has been shown to arise from peroxidative destruction of polyunsaturated lipid membranes. A high rate of lipofuscin formation is indicated by the occurrence of brown atrophy of the heart in relatively young persons who died of conditions that were associated with inanition. Such lipofuscin formation suggests the importance of dietary antioxidants in preventing peroxidative damage to mitochondria. A by-product of lipid peroxidation, malonaldehyde, can react with nuclear DNA, blocking template activity. Nuclear damage of this kind could reduce the capacity for protein synthesis and limit mitochondrial and contractile protein replacement. Such a limitation would contribute to heart failure during stress. Peroxidative damage to the myocardium is cumulative and irreversible.
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PMID:The origin of lipofuscin and possible consequences to the myocardium. 57 66

Angiotensin-converting enzyme (ACE) inhibitors are widely used for treatment of heart failure after myocardial infarction (MI). The beneficial effects consist of a combination of hemodynamic effects and interference with cardiac structural alterations. These effects are believed to depend on inhibition of angiotensin II (AII) formation and thus diminished angiotensin receptor stimulation. We administered the angiotensin II-1 (AT-1) receptor antagonist losartan during and after completion of the repair phase of an MI to investigate involvement of the AT-1 receptor in the above described effects of captopril. MI reduced cardiac output (CO) (sham 94 +/- 4 ml/min, MI 78 +/- 5 ml/min) and maximal CO (sham 154 +/- 4, MI 107 +/- 5 ml/min, respectively). Losartan (15 mg/kg/day) resulted in a rightward shift of the AII pressor dose-response curve by a factor of 32-40. Neither CO nor COVL,max was affected by losartan treatment in either phase (late treatment CO = 78 +/- 5, COVL,max = 118 +/- 9 ml/min). Although early treatment with losartan reduced cardiac hypertrophy measured as heart weight, DNA synthesis was reduced only slightly. In contrast, collagen deposition was inhibited completely. The results suggest that the effects of captopril in rats after MI are not dependent on AT-1 receptor-mediated mechanisms.
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PMID:Angiotensin II receptor blockade after myocardial infarction in rats: effects on hemodynamics, myocardial DNA synthesis, and interstitial collagen content. 128 Jul 40

Human parvovirus B19 is a recently recognized cause of hydrops fetalis. It is a small, single-stranded DNA virus, which preferentially infects late erythroid precursors and produces red blood cell (RBC) aplasia, fetal anemia, and cardiac failure. Infection is accompanied by characteristic intranuclear inclusions in fixed and circulating RBC precursors. These inclusions have been shown to contain virus particles by electron microscopy and in situ hybridization. Infection of the fetus, mother, and newborn infant can be diagnosed by serological and molecular methods selected to match the stage of the infection. Recent work has shown that parvovirus B19 can infect cells other than erythroid precursors, and that additional mechanisms such as myocarditis may contribute to hydrops fetalis in some cases. Infected fetuses are not always hydropic. Maternal infection results in increased abortion and stillbirth even in the absence of transplacental transmission, which occurs in approximately one third of infected mothers. The overall risk of fetal loss following maternal exposure is much less than previously thought, and may be less than 3% in the first 20 weeks of gestation or approximately 10% if the mother is actually infected. Although parvoviruses are teratogenic in animals, there is no evidence that B19 is a significant teratogen in man. The long-term outlook of survivors of intrauterine infection, including those successfully treated by intrauterine blood transfusion, appears to be good, but requires further study.
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PMID:Parvovirus infection of the human fetus and newborn. 156 88

To examine the status of ATP-sensitive K+ (K+ATP) channels and 1,4-dihydropyridine-sensitive Ca2+ (Ca2+DHP) channels during experimental cardiac failure, we have measured the radioligand binding properties of [3H]glyburide and [3H]PN 200 110, respectively, in tissue homogenates from the rat cardiac left ventricle, right ventricle, and brain 4 wk after myocardial infarction induced by left coronary artery ligation. The maximal values (Bmax) for [3H]glyburide and [3H]PN 200 110 binding were reduced by 39 and 40%, respectively, in the left ventricle, and these reductions showed a good correlation with the right ventricle-to-body weight ratio in heart-failure rats. The ligand binding affinities were not altered. In the hypertrophied right ventricle, Bmax values for both the ligands were not significantly different when data were normalized to DNA content or right ventricle weights but showed an apparent reduction when normalized to unit protein or tissue weight. Moderate reductions in channel densities were observed also in whole brain homogenates from heart failure rats. Assessment of muscarinic receptors, beta-adrenoceptors and alpha 1-adrenoceptors by [3H]quinuclidinyl benzilate, [3H]dihydroalprenolol, and [3H]prazosin showed reductions in left ventricular muscarinic and beta-adrenoceptor densities but not in alpha 1-adrenoceptor densities, consistent with earlier observations. It is suggested that these changes may in part contribute to the pathology of cardiac failure.
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PMID:Regulation of K+ and Ca2+ channels in experimental cardiac failure. 166 Oct 95

This article describes investigations of several aspects of the molecular biology of the human renin gene and the three-dimensional structure of renin and its precursor, prorenin. Because of the importance of the RAS in hypertension, heart failure, renal failure, and possibly other disorders such as atherosclerosis, it is critical to understand the detailed control of this system. This control involves regulation at the transcriptional level, folding of prorenin, sorting of prorenin to a regulated pathway where it is proteolytically cleaved to renin and released in response to secretogogues, constitutive release of uncleaved prorenin, and nonproteolytic activation of prorenin. Currently there is great interest not only in the control of renin in the kidney, the sole source of circulating renin, but also at extrarenal sites where RAS activity may regulate cardiovascular functions. The renin gene was found to be expressed significantly in the renal juxtaglomerular cells and several other cell types. Most tissue culture cells did not express the gene; exceptions were cultured SK-LMS-1 cells and cAMP-stimulated human lung fibroblasts. Cultured human uterine-placental cells expressed the human renin gene at levels higher than in other cell types assessed. Renin mRNA had the same start site in the placental cells as the kidney and was regulated by calcium ionophores and cAMP. Thus, these cells provide primary nontransformed human cells to study the homologous human promoter. Transfected renin promoters showed cell type-specific expression and cAMP responsiveness in these cells in constructs containing as few as 102 bp of 5'-flanking DNA. DNA upstream from this appears to contain an inhibitory element(s) that may have some tissue specificity in its distribution. The cAMP response is not due to cAMP induction of a transcription factor that secondarily affects the renin promoter. A novel element may be involved, since the promoter does not contain a CRE element that mediates many cAMP responses, and the cells do not appear to respond to another known cAMP-responsive transcription factor, AP-2. Studies with transfected vectors expressing a mutant cAMP-responsive protein kinase A regulatory subunit suggest that cAMP is not responsible for basal renin promoter activity in the placental cells. By contrast, cAMP induces in essence gene activation in WI26VA4 transformed human lung fibroblasts in which renin mRNA levels increase by up to 150-fold in response to forskolin. Thus, cAMP may activate renin gene expression under certain circumstances and tissue-specific renin gene expression may be directed by more than one mechanism.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Molecular biology of human renin and its gene. 174 21

Angiotensin I converting enzyme (ACE) inhibitors are widely used in the treatment of heart failure. It is not known whether the beneficial effects of ACE inhibition are only due to a reduction in pre- and afterload or whether ACE inhibition also has direct effects on cardiac remodeling processes after myocardial infarction. In addition, the effects of differential timing of the treatment are not known. The left coronary artery was ligated in rats to induce a myocardial infarction. Control rats received no treatment. Captopril was given via s.c. placed minipumps (500 micrograms/kg.h) in the first 3 weeks or in the third and fourth week after induction of the myocardial infarction. The structural changes of the heart were investigated. Early after ligation the left ventricle was dilated in association with a marked, but transient DNA synthesis in the remaining left ventricle; the amount of collagen also increased. Early captopril treatment blocked this response, while late treatment had no effects. We suggest that the negative effects of early captopril treatment are due to an interference with the normal adaptive responses of the heart to the loss of muscle, probably through interactions at the cellular level.
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PMID:Angiotensin I converting enzyme inhibitors and cardiac remodeling. 182 81

A 52-year-old man, who came from Kagoshima prefecture, was hospitalized because of lumbago and lymphadenopathy. On admission, mild anemia and leukocytosis with atypical lymphoid cells were seen in the peripheral blood. Flow cytometry of the abnormal lymphocytes showed that they expressed CD4, and CD25, but not CD8. Anti HTLV I antibody was expressed in the serum. Atypical lymphoid cells had proviral DNA with restriction enzyme EcoRI. Lymphnode biopsy was performed and the specimens of lymphnode showed diffuse infiltration of abnormal lymphocytes. So we diagnosed Adult T-cell leukemia lymphoma. The patient's serum calcium level was increased, so he lost consciousness and became oliguric and developed acute renal failure. Hemodialysis was required to control azotemia. During the time of hemodialysis, cardiac arrest was occurred and he died. Autopsy confirmed the presence of a metastatic calcification in various organs, such as myocardium, alveolar septa of the lungs, and gastric mucosa. A metastatic calcinosis was found in the myocardium, which was thought to be the cause of his heart failure. But at the ATLL cells didn't infiltrate in the myocardium. Calcinosis was a significant complication of neoplastic disease in these patients and contributed to morbidity and mortality.
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PMID:[Adult T-cell leukemia lymphoma with metastatic calcification]. 192 Aug 88

Although most cases of viral myocarditis are subclinical, some patients develop overt symptomatic disease. These patients may present with findings that range from benign myopericarditis to frank heart failure. Furthermore, a growing body of evidence links viral myocarditis with idiopathic dilated cardiomyopathy, sudden death, and chronic arrythmias. The pathogenesis of the disease is currently incompletely understood in humans but is being investigated in animal models. A multifactorial process involving direct viral damage, autoimmunity, and possibly vascular damage is emerging. Breakthroughs in rapid diagnosis, such as the use of DNA probes, are occurring and may soon provide the opportunity for early intervention. Although there is currently no widely accepted standard of treatment, promising new therapeutic modalities are under investigation. These include the use of general immunosuppressive agents, T cell monoclonal antibody, interferon, specific immunization, and synthetic antiviral agents.
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PMID:Viral myocarditis. 196 11

The sequence of atrial natriuretic factor (ANF) has been determined, as well as the complete structure of the rat and human complementary DNA and gene. ANF and ANF messenger RNA are present not only in atria but also in ventricles. The circulating form of ANF has been identified as the C-terminal of the molecule, ANF (Ser 99-Tyr 126). The isolated secretory granules of rat atrial cardiocytes contain only pro-ANF (Asn 1-Tyr 126). An enzyme (IRCM-SP1) has been isolated from heart atria and ventricles. This enzyme is highly specific in cleaving ANF (Asn 1-Tyr 126), to yield ANF (103-126), (102-126), and (99-126). In target cells, ANF produces a rise in cyclic guanosine 3',5'-monophosphate (cGMP) due to activation of particulate guanylate cyclase, and inhibition of adenylate cyclase leading in some cases to a decrease in cyclic adenosine 3',5'-monophosphate (cAMP). ANF produces relaxation of rabbit and rat aortic strips, inhibits steroidogenesis in both zona glomerulosa and zona fasciculata cells, and inhibits the release of arginine vasopressin from the isolated rat hypothalamohypophysial preparation in vitro but decreases AVP release in vivo only at pharmacological doses. In all forms of experimental hypertension, plasma levels of ANF are increased and, at some time periods, atrial levels are also decreased. The ventricular levels of immunoreactive ANF are also increased in renal hypertension. Infusion of ANF by minipumps decreases the blood pressure near control levels in several models of experimental hypertension. In cardiomyopathic hamsters with heart failure, the atrial levels of immunoreactive ANF are decreased while the plasma and ventricular levels are increased.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The heart as an endocrine gland. 282 60

The sequence of myocardial changes in the mouse induced by doxorubicin (Dx) treatment (10 mg/kg i.v.) has been investigated by electron microscopy with the help of the zinc iodide-osmium tetroxide (ZIO) technique. Accumulation of ZIO-reactive material, possibly oxidized glutathione and other disulfides, in the sarcoplasmic reticulum (S.R.) is among the earliest (1 h after Dx injection), more prominent and persistent findings (up to 100 days). It may have a pathogenic relationship with a number of functional and morphologic changes occurring in myocardial cells, including impairment of calcium transport and contractility, S.R. dilation up to extensive vacuolization, as well as inhibition of DNA, RNA and protein synthesis leading to atrophy and disruption of sarcomeres. The latter finding, first appearing in a few cells 4 to 7 days after Dx and progressively increasing in severity and extension during the next 3 months, may represent a key factor in the evolution of chronic cardiomyopathy to cardiac insufficiency. In most cells, only a minority of mitochondria showed obvious ultrastructural lesions, which were first observed 24 h after treatment and disappeared by the end of the first month, when no more mitochondrial damage was found outside degenerating cells. The myocardium of mice receiving multiple Dx injections (4 mg/Kg, 10 times, or 9 mg/Kg, 5 times) showed the same changes observed in animals treated with a single dose, though they were more severe and extensive.
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PMID:Early and late sarcoplasmic reticulum changes in doxorubicin cardiomyopathy. An ultrastructural investigation with the zinc iodide-osmium tetroxide (ZIO) technique. 286 24


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