Developmental cell-specific regulation of Na(+)-K(+)-ATPase alpha 1-, alpha 2-, and alpha 3-isoform gene expression.

Na(+)-K(+)-activated adenosine triphosphatase (Na(+)-K(+)-ATPase) is the integral membrane protein that maintains the Na(+)-K(+) electrochemical gradient across the plasma membrane. Because of the importance of the Na(+)-K(+) electrochemical gradient to fundamental and specialized cell functions, we investigated the cell-specific modulation of Na(+)-K(+)-ATPase alpha-subunit isoform (alpha 1, alpha 2, and alpha 3) gene expression in different stages of postimplantation mouse embryos and neonatal rat tissues by in situ hybridization with use of isoform-specific rat-derived antisense RNA probes. At early organogenesis (9.

Immunologic identification of Na+,K(+)-ATPase isoforms in myocardium. Isoform change in deoxycorticosterone acetate-salt hypertension.

There are three isoforms of the catalytic (alpha) subunit of the Na+,K(+)-ATPase, each derived from a different gene, that differ in their sensitivity to inhibition by cardiac glycosides. Antibodies specific for the three isoforms were used to study Na+,K(+)-ATPase isoform expression in ventricular myocardium, where an understanding of digitalis receptor diversity is most important. In the rat heart, there is simultaneous expression of two isoforms in adult ventricle, and immunofluorescence studies demonstrated that both isoforms are expressed uniformly in cardiomyocytes.

Differential interaction of the dual alpha tropomyosin/N5 enhancer with multiple DNA binding proteins: N5 is a putative novel z-ZIP DNA binding protein.

The alpha tropomyosin (TM)/N5 enhancer is an SV40-like mammalian enhancer comprised of a 99 bp repeat with modular cis-acting regulatory elements exhibiting apparent hierarchical organization. The enhancer differentially regulates the alpha TM and N5 transcription units which exhibit distinct tissue-specific expression patterns and interacts with multiple myotube-associated nuclear DNA binding proteins that varied in size and amount. To further characterize the interaction with multiple myotube nuclear factors, comparative southwestern blot analyses were done with a panel of strategic DNA probes representative of modular enhancer sequences in the alpha TM/N5 enhancer and respective alpha TM and N5 promoter regions.

[The versatility of anterograde/retrograde cardioplegia in heart surgery].

Eighty patients underwent open-heart surgery from March 1990 to March 1993. We used combined aortic root (antegrade)/coronary sinus (retrograde) perfusion for cardioplegia delivery as a means of myocardial protection. The special retroplegia cannula was introduced to the coronary sinus (CS) in 67 patients by the transatrial (blind intubation) after one cannula cava insertion; the CS was cannulated under direct vision by right atriotomy after bicaval cannulation in 13 patients.

[Calcified embolism of the coronary artery due to the degeneration of a bioprosthesis in the aortic position].

We present a case of arterial coronary embolism by calcified material of a bioprosthesis of bovine pericardium of the INC in aortic position 8 years after its implantation. Echocardiogram and catheterization with coronarography demonstrated prosthetic aortic dysfunction and normal coronaries. The patient complained of stable angor and dyspnea.

The alpha 1 Na(+)-K+ pump of the Dahl salt-sensitive rat exhibits altered Na+ modulation of K+ transport in red blood cells.

The properties of the alpha 1 Na(+)-K+ pump were compared in Dahl salt-sensitive (DS) and salt-resistant (DR) strains by measuring ouabain-sensitive fluxes (mmol/liter cell x hr = FU, Mean +/- SE) in red blood cells (RBCs) and varying internal (i) and external (o) Na+ and K+ concentrations. Kinetic parameters of several modes of operation, i.e.

Ross operation using a bovine bioprosthetic valve with autologous pericardial conduit in the pulmonary position.

Between 1 February 1992 and 1 March 1993, we performed Ross's aortic replacement in 7 men and 4 women with rheumatic heart disease. The patients' ages ranged from 22 to 60 years (mean, 41 years). All 11 patients had aortic valve disease; 2 also had mitral valve disease.

[Enteropathogenic microorganisms in children with acute diarrhea in 2 hospitals of Rosario, Argentina].

As part of a multicenter collaborative study the relative frequency of enteropathogenic agents in children less than 5 years of age with acute diarrhea was determined. Rates of isolation were similar as regards sex, age, and season. The frequency of polymorphonuclear cells (PMN) in the stools was significantly higher among patients requiring admission in comparison with ambulatory patients.

Genetics of hypertension A multidisciplinary challenge.

Hypertension is a prevalent complex polygenic disease mandating directive concerted multidisciplinary efforts in the dissection of its genetic basis. Identification of the genes involved in the etiology of genetic hypertension (hypertension genes) will lead to an elucidation of primary pathogenic mechanisms of hypertension, target organ complications, and interactions with environmental factors. This can thus form the basis for directive integrated management of hypertension.

Alteration of alpha 1 Na+,K(+)-ATPase 86Rb+ influx by a single amino acid substitution.

The sodium- and potassium-dependent adenosine triphosphatase (Na+,K(+)-ATPase) maintains the transmembrane Na+ gradient to which is coupled all active cellular transport systems. The R and S alleles of the gene encoding the Na+,K(+)-ATPase alpha 1 subunit isoform were identified in Dahl salt-resistant (DR) and Dahl salt-sensitive (DS) rats, respectively. Characterization of the S allele-specific Na+,K(+)-ATPase alpha 1 complementary DNA identified a leucine substitution of glutamine at position 276.

The risk of intentional dissolution of the smear layer after mechanical preparation of root canals.

The root canals of 27 caries-free human cuspids were divided into 3 groups of 9 teeth each. Group I was mechanically prepared with reamers and files. Alternate irrigation with 5.

Regulation of alpha-tropomyosin and N5 genes by a shared enhancer. Modular structure and hierarchical organization.

We have identified a 99-base pair (bp) tandem repeat consisting of two modules/repeat: a 40-bp-long d(CA.GT)20 potential Z-DNA sequence and a 59-bp-long unique sequence. This repeat is located between and differentially regulates two transcription units, rat alpha-tropomyosin and N5, organized in "head-to-head" orientation.

Isoform-specific modulation of Na+, K+-ATPase alpha-subunit gene expression in hypertension.

Sodium, potassium-adenosine triphosphatase (Na+, K+-ATPase) is hypothesized to be involved in systemic vascular hypertension through its effects on smooth muscle reactivity and myocardial contractility. By means of RNA blot analyses of cardiac, aortic, and skeletal muscle RNAs in two rat hypertensive models, Na+,K+-ATPase alpha-subunit messenger RNA isoforms (alpha 2 and alpha 3) were shown to be deinduced in response to increased intravascular pressure. The changes were observed after 48 hours or more of experimental hypertension.

Heart-rate spectral analysis: a noninvasive probe of cardiovascular regulation in critically ill children with heart disease.

Children may die suddenly and unexpectedly following cardiac surgery, even while receiving intensive medical care, when current noninvasive and invasive monitoring techniques fail to warn us of an impending problem. This report examines the efficacy of heart-rate spectral analysis, a noninvasive method that quantitates the beat-to-beat fluctuations in heart rate, in characterizing and tracking cardiovascular regulatory status. A total of 45 heart-rate fluctuation studies, performed on selected patients, at the bedside, using heart-rate spectral analysis, were retrospectively correlated with clinical events.

Cloning and tissue distribution of rat heart fatty acid binding protein mRNA: identical forms in heart and skeletal muscle.

A fatty acid binding protein (FABP) has been identified and characterized in rat heart, but the function and regulation of this protein are unclear. In this study the cDNA for rat heart FABP was cloned from a lambda gt11 library. Sequencing of the cDNA showed an open reading frame coding for a protein with 133 amino acids and a calculated size of 14776 daltons.

Three differentially expressed Na,K-ATPase alpha subunit isoforms: structural and functional implications.

We have characterized cDNAs coding for three Na,K-ATPase alpha subunit isoforms from the rat, a species resistant to ouabain. Northern blot and S1-nuclease mapping analyses revealed that these alpha subunit mRNAs are expressed in a tissue-specific and developmentally regulated fashion. The mRNA for the alpha 1 isoform, approximately equal to 4.