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

One hundred thousand (100,000) people are living--thanks to Artificial Kidneys. We need more emphasis on Home Dialysis. The immediate future will bring us: WAK (Wearable Artificial Kidney) FAK (Filtrating Artificial Kidney) PAK (Peritoneal Artificial Kidney) HAK (Hemoperfusion Artificial Kidney). Intra-aortic balloon pumps and transapical left ventricular bypass may offer patients now dying from heart failure, a possibility to either recover or be maintained until an artificial heart is available. Our aim is to create an Artificial Heart to totally replace the irreparably sick human heart. We have obtained survival times up to more than six months after total replacement of the natural heart in calves. Dr. Steve Jacobsen's Artificial Arm is activated by electromyographic signals that are derived from the shoulder muscles. The Artificial Eye makes use of direct stimulation of the visual cortex of the brain by arrays of electrodes situated against the visual cortex. For the Artificial Ear, we stimulate the fibers of the eighth nerve by threading platinum wires up into the cochlea. Deaf volunteers can hear rhythm, loudness and some pitch.
 ...
PMID:Exponential growth and future of artificial organs. 61 76

Cardiac hypertrophy involves the accumulation of extracellular matrix proteins, such as fibronectin, leading to increasing myocardial stiffness, ventricular dysfunction and heart failure. To better understand the possible role of extracellular matrix-evoked intracellular signalling in ventricular myocytes, we investigated the effect of fibronectin on myocyte hypertrophic responses using cell culture models. Cell size in myocytes cultured on fibronectin-coated dishes was three times larger than that grown on non-coated dishes. However, the number of cells on fibronectin-coated dishes was not changed throughout the experiment. Protein synthesis was significantly increased by fibronectin, as were synthesis of atrial and brain natriuretic peptides. Fibronectin also elicited actin reorganization, co-localization of beta 1 integrin and vinculin, formation of focal adhesions and tyrosine phosphorylation of focal adhesion kinase in myocytes. These fibronectin-mediated effects were inhibited in a dose-dependent manner by GRGDSP, a competitive antagonist of the fibronectin receptors; GRGDSP had no effect on cell number or viability. Blocking antibody for beta 1 and beta 3 integrin significantly suppressed fibronectin-induced secretion of natriuretic peptides. Myocyte hypertrophy was observed in myocyte-nonmyocyte co-culture that reflects more closely the myocyte environment in vivo. GRGDSP may also suppress the myocyte hypertrophic response in the co-culture. These findings demonstrate that the interaction of fibronectin and RGD-dependent integrins is involved in the hypertrophic responses of myocyte in vitro, and suggest that extracellular matrix proteins such as fibronectin are not merely passive adhesive molecules but are active participants in processes leading to myocyte hypertrophy.
 ...
PMID:Outside-in signalling of fibronectin stimulates cardiomyocyte hypertrophy in cultured neonatal rat ventricular myocytes. 1077 82

It has been 100 years since the discovery of renin by Bergman and Tigerstedt. Since then, numerous studies have advanced our understanding of the renin-angiotensin system. A remarkable aspect was the discovery that angiotensin II (AngII) is the central product of the renin-angiotensin system and that this octapeptide induces multiple physiological responses in different cell types. In addition to its well known vasoconstrictive effects, growing evidence supports the notion that AngII may play a central role not only in hypertension, but also in cardiovascular and renal diseases. Binding of AngII to the seven-transmembrane angiotensin II type 1 receptor is responsible for nearly all of the physiological actions of AngII. Recent studies underscore the new concept that activation of intracellular second messengers by AngII requires tyrosine phosphorylation. An increasing number of tyrosine kinases have been shown to be activated by AngII, including the Src kinase family, the focal adhesion kinase family, the Janus kinases and receptor tyrosine kinases. These actions of AngII contribute to the pathophysiology of cardiac hypertrophy and remodeling, vascular thickening, heart failure and atherosclerosis. In this review, we discuss the important role of tyrosine kinases in AngII-mediated signal transduction. Understanding the importance of tyrosine phosphorylation in AngII-stimulated signaling events may contribute to new therapies for cardiovascular and renal diseases.
 ...
PMID:Angiotensin II mediated signal transduction. Important role of tyrosine kinases. 1106 26

Growth hormone (GH) has been reported to be useful to treat heart failure. To elucidate whether GH has direct beneficial effects on the heart, we examined effects of GH on oxidative stress-induced apoptosis in cardiac myocytes. TUNEL staining and DNA ladder analysis revealed that hydrogen peroxide (H2O2)-induced apoptosis of cardiomyocytes was significantly suppressed by the pretreatment with GH. GH strongly activated extracellular signal-regulated kinases (ERKs) in cardiac myocytes and the cardioprotective effect of GH was abolished by inhibition of ERKs. Overexpression of dominant negative mutant Ras suppressed GH-stimulated ERK activation. Overexpression of Csk that inactivates Src family tyrosine kinases also inhibited ERK activation evoked by GH. A broad-spectrum inhibitor of protein tyrosine kinases (PTKs), genistein, strongly suppressed GH-induced ERK activation and the cardioprotective effect of GH against apoptotic cell death. GH induced tyrosine phosphorylation of EGF receptor and JAK2 in cardiac myocytes, and an EGF receptor inhibitor tyrphostin AG1478 and a JAK2 inhibitor tyrphostin B42 completely inhibited GH-induced ERK activation. Tyrphostin B42 also suppressed the phosphorylation of EGF receptor stimulated by GH. These findings suggest that GH has a direct protective effect on cardiac myocytes against apoptosis and that the effect of GH is attributed at least in part to the activation of ERKs through Ras and PTKs including JAK2, Src, and EGF receptor tyrosine kinase.
 ...
PMID:Growth hormone signalling and apoptosis in neonatal rat cardiomyocytes. 1168 20

Quantification of mRNAs from extremely small human samples remains a challenge. Requiring minimal amounts of tissue and no post-reaction manipulation, real-time reverse transcriptase-polymerase chain reaction (RT-PCR) is an attractive method to quantitatively assess the expression of rare mRNAs. We evaluated the applicability of the technique on RNA extracted from human endomyocardial biopsies and isolated cardiomyocytes, and compared the technique to the RT-competitive PCR approach. Primers and probes were designed to amplify the three subtypes of human beta -adrenoceptors (beta1-, beta2- and beta3 AR), as well as reference genes such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Hypoxanthine-guanine phosphoribosyltransferase (HPRT), and the oncogene ABL by real-time RT-PCR. Specific primers and a deleted competitor were synthetized to compare the quantitation of the beta 3 AR mRNA expression by RT-competitive PCR. We validated the technique on human cardiomyocytes either freshly isolated or selectively excised from fixed sections of human myocardium by Laser Capture Microdissection. The standard curves obtained for the cDNA's analysed showed mean slopes comprised between -3.3 and -3.7. Inter- and intra-assay variability of gene quantitation was reflected by mean values of the variance coefficients of Ct of 4.84+/-1.13% and 2.73+/-0.39% or 3.32+/-1.03% and 2.21+/-0.24% (corresponding to percent variances of copy numbers of 83.07+/-12.72% and 34.45+/-9.03% or 47.40+/-8.59% and 23.83+/-3.16%) for human beta3 AR and GAPDH genes, respectively. The expression of GAPDH, HPRT and ABL mRNA was characterized by a very low dispersion of individual values across cardiac pathologies, suggesting that these genes may be used as reference genes in quantitative PCR studies. Finally, we applied the technique to detect rare mRNAs, such as beta -AR mRNAs, from small human endomyocardial biopsies and even isolated cardiomyocytes. Real-time RT-PCR is appropriate to quantitate rare messenger RNAs, including in extremely small human tissue samples. This method appears very promising for futures studies of gene expression in several pathophysiological conditions, including heart failure.
 ...
PMID:Real-time RT-PCR for the detection of beta-adrenoceptor messenger RNAs in small human endomyocardial biopsies. 1173 59

Some clinical trials perform repeated measurement over time and estimate clinically relevant change in an instrument's score with global ratings of perceived change or so-called transition questions. The conceptual and methodological difficulties in estimating the magnitude of clinically relevant change over time in health-related functional status (HRFS) are discussed. This paper investigates the concordance between the amount of serially assessed change with effect size estimates (the researcher's perspective) and global ratings of perceived change (the patient's perspective). A total of 217 patients who were scheduled for diagnostic examination were included, and the Minnesota Living with Heart Failure Questionnaire, extended with MOS-20 items, was assessed before and after medical intervention (percutaneous transluminal coronary angioplasty, coronary artery bypass grafting or pharmaco-therapy). Global questions were applied to assess perceived change over time for every item from domains of physical and emotional functioning and used as the external criterion of relevant change in the analysis of items. Global questions corresponding with overall change in these domains were used in the comparison of change in physical and emotional functioning scales. Two effect size indices were used: (i) ES (mean change/SDpooled) and (ii) ES (mean change/SDchange). A method is described to calculate a value indicating the extent of discordance between the researcher's interpretation of magnitude of change and the external criterion (the patient's perspective). Findings suggest that effect size (ES) (mean change/SDpooled) was in keeping with the magnitude of change indicated by patients' judgements, or their category of subjective meaning, for all scales. Furthermore, in cases in which the magnitude of change estimated with the SRM (mean change/SDchange) was not confirmed empirically by the external criterion ratings, the discordance could be interpreted as a trivial discordance.
 ...
PMID:How to validate clinically important change in health-related functional status. Is the magnitude of the effect size consistently related to magnitude of change as indicated by a global question rating? 1173 31

Proline-rich tyrosine kinase 2 (PYK2) is a member of the focal adhesion kinase (FAK) family of nonreceptor protein tyrosine kinases. PYK2 has been implicated in linking G protein-coupled receptors to activation of mitogen-activated protein kinase cascades and cellular growth in a variety of cell types. To determine whether PYK2 expression and phosphorylation is altered in left ventricular (LV) myocardium undergoing LV hypertrophy (LVH) and heart failure in vivo, suprarenal abdominal aortic coarctation was performed in 160-g male Sprague-Dawley rats. Immunohistochemistry and Western blotting were performed on LV tissue 1, 8, and 24 wk after aortic banding. Aortic banding produced sustained hypertension and gradually developing LVH. PYK2 levels were increased 1.8 +/- 0.2-, 2.7 +/- 0.6-, and 2.0 +/- 0.2-fold in 1-, 8-, and 24-wk banded animals compared with their respective sham-operated controls. The increase in PYK2 expression was paralleled by an increase in PYK2 phosphorylation, both of which preceded the development of LVH. Immunohistochemistry revealed that enhanced PYK2 expression occurred predominantly in the cardiomyocyte population. Furthermore, there was a high degree of correlation (R = 0.75; P < 0.001) between the level of PYK2 and the degree of LVH in 24-wk sham and banded animals. In contrast, FAK levels and FAK phosphorylation were not increased before the development of LVH. However, there was a high degree of correlation (R = 0.68; P < 0.001) between the level of FAK and the degree of LVH in 24-wk sham and banded rats. There was also a significant increase in the ratio of phosphospecific anti-FAK to FAK at this time point. These data are consistent with a role for PYK2 in the induction of pressure overload-induced cardiomyocyte hypertrophy, and suggest that PYK2 and FAK have distinctly different roles in LVH progression.
 ...
PMID:PYK2 expression and phosphorylation increases in pressure overload-induced left ventricular hypertrophy. 1212 18

Integrins are heterodimeric cell-surface receptors that link the extracellular matrix and the intracellular cytoskeleton and function as mechanotransducers. Signaling through integrins is important for cell growth, migration, and survival. Extracellular matrix is altered in the myocardium during hypertrophic induction and the transition to heart failure. The role of integrins in this process is poorly understood. Recently, integrin subunits have been identified that are dominantly expressed in striated muscle. We tested the hypothesis that since integrins are mechanotransducers, their expression and signaling would be modulated with murine left ventricular hemodynamic loading. The acute and chronic effects of pressure overload on changes in the expression of integrins, as well as related integrin-mediated signaling events were studied. Acute pressure loading increased phosphorylation of focal adhesion kinase, p42 and p44 extracellular signal-regulated kinase. Chronic loading: (1) increased expression of alpha1, alpha5, and beta1 integrin transcripts and (2) increased protein expression of integrin subunits which are dominantly expressed in striated muscle (alpha7 and beta1D) both by western blotting and immunofluorescent microscopy. These results show that adaptive responses of the myocardium to pressure overload include acute modulation of integrin-related signaling molecules and more chronic changes effect expression of integrin subunits, including ones dominantly expressed in muscle.
 ...
PMID:Modulation of integrins and integrin signaling molecules in the pressure-loaded murine ventricle. 1248 8

Angiotensin II (AngII) plays a critical role in control of cardiovascular and renal homeostasis. In addition to its physiological action as a vasoconstrictor, growing evidence supports the notion that AngII contributes to cardiovascular diseases such as hypertension, atherosclerosis, and heart failure. The physiological and pathological actions of AngII in adults are mediated largely via the AngII type 1 receptor (AT1R), a heterotrimeric G-protein-coupled receptor (GPCR). Besides coupling with heterotrimeric G proteins to activate phospholipase C-beta (PLC-beta), AT1R also activates receptor tyrosine kinases (PDGF-R, EGF-R and IGF-R) and non-receptor tyrosine kinases (Src, Fyn, Yes, proline-rich tyrosine kinase 2 (Pyk2), focal adhesion kinase (FAK) and JAK2). These tyrosine kinases play critical roles in AngII-stimulated cell signal events.
 ...
PMID:Angiotensin II signaling pathways mediated by tyrosine kinases. 1267 64

Focal adhesion kinase (FAK) and focal adhesion kinase-related nonkinase (FRNK) are likely involved in mechanical signaling during hypertension. We investigated expression, subcellular distribution, and phosphorylation of FAK, as well as FRNK in left ventricles of spontaneously hypertensive heart failure rats. Compared with normotensive controls, FAK and FRNK increased in left ventricles of hypertensive rats. Increased FAK and FRNK were mainly present in membrane cytoskeleton and nuclear fractions. Confocal microscopy demonstrated that FAK and FRNK translocated to nuclei and intercalated disks in cardiac myocytes from hypertensive rats. Serine and tyrosine phosphorylation of FAK increased dramatically in hypertensive rats. FAK phosphorylated at tyrosine 397 was present in membranes and intercalated disks, but not in nuclei. FAK was also phosphorylated on serine 722 but not on serine 910. In contrast, FRNK was phosphorylated on serine 217, the equivalent site of FAK serine 910, but not serine on 30, the homologous site of FAK serine 722. Serine phosphorylated FAK and FRNK accumulated in membranes and nuclei but not in intercalated disks. Nuclear translocation of FAK and FRNK may play important roles in regulating mechanical signal transduction in cardiac myocytes.
 ...
PMID:Subcellular redistribution of focal adhesion kinase and its related nonkinase in hypertrophic myocardium. 1273 87


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