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J Soler

Publications and source records attributed to J Soler.

At least 217 records · Page 12Linked to original sources
PubMed1984

Method for the simultaneous labelling of terminal deoxynucleotidyl transferase (TdT) and membrane antigens.

A method for the simultaneous labelling of terminal deoxynucleotidyl transferase (TdT) and membrane antigens is described. TdT is visualised in the cell nucleus with the peroxidase-antiperoxidase (PAP) method, and the immunogold method is used in combination with monoclonal antibodies against membrane antigens. The morphology of the labelled cells is well preserved for analysis by light microscopy and the preparations obtained can be kept permanently. This method is useful for the analysis of mixed cell proliferations, particularly in leukaemias.

Antigens, Surface↗
PubMed1984

Natural history of severe left ventricular dysfunction after myocardial infarction.

The prevalence and prognosis of severe left ventricular dysfunction after infarction was prospectively analyzed in a series of 259 male patients aged 60 years or less surviving an acute myocardial infarction. All patients underwent coronary angiography 30 days after the acute event and were followed up for a mean period of 34 months (range, 15 to 55 months). Forty-five patients (17 percent) were found to have severe left ventricular dysfunction (ejection fraction less than or equal to 30 percent). Comparison of patients with and without severe impairment of left ventricular function showed the former to have a lower cardiac index (p less than 0.001), higher left ventricular end-diastolic volume index (p less than 0.001), and a higher prevalence of three-vessel disease (p less than 0.025) and of total or subtotal occlusion of at least one coronary artery (p less than 0.025). While the occurrence of congestive heart failure was higher in patients with severe left ventricular dysfunction (p less than 0.001), the probability of developing angina was similar in both groups. Cox's regression analysis showed ejection fraction to be the only independent predictor of survival in patients with severe impairment of left ventricular function. An ejection fraction of 20 percent or less identified a subset of patients with the highest mortality (62 percent at four years), significantly different from that of patients whose ejection fraction was between 21 and 30 percent (28 percent) (p less than 0.001).

Adult↗
PubMed1983

ATP, ADP and AMP on the regulation of lactate dehydrogenase activity of Phycomyces blakesleeanus.

1. The inhibition of ATP, ADP and AMP on lactate dehydrogenase activity from Phycomyces blakesleeanus was investigated kinetically at pH 6.0 and 7.5. 2. At pH 6.0 ATP was more effective as inhibitor than ADP and AMP. 3. All three nucleotides bind cooperatively to the enzyme, ATP and ADP decrease the positive homotropic interactions of NADH at pH 6.0. 4. The results obtained may contribute to explain the regulation of lactate dehydrogenase from Phycomyces blakesleeanus at acid pH values.

Adenosine Diphosphate↗
PubMed1982

Lactate dehydrogenase in Phycomyces blakesleeanus.

1. An NAD-specific L(+)-lactate dehydrogenase (EC 1.1.1.27) from the mycelium of Phycomyces blakesleeanus N.R.R.L. 1555 (-) was purified approximately 700-fold. The enzyme has a molecular weight of 135,000-140,000. The purified enzyme gave a single, catalytically active, protein band after polyacrylamide-gel electrophoresis. It shows optimum activity between pH 6.7 and 7.5. 2. The Phycomyces blakesleeanus lactate dehydrogenase exhibits homotropic interactions with its substrate, pyruvate, and its coenzyme, NADH, at pH 7.5, indicating the existence of multiple binding sites in the enzyme for these ligands. 3. At pH 6.0, the enzyme shows high substrate inhibition by pyruvate. 3-hydroxypyruvate and 2-oxovalerate exhibit an analogous effect, whereas glyoxylate does not, when tested as substrates at the same pH. 4. At pH 7.5, ATP, which inhibits the enzyme, acts competitively with NADH and pyruvate, whereas at pH 6.0 and low concentrations of ATP it behaves in a allosteric manner as inhibitor with respect to NADH, GTP, however, has no effect under the same experimental conditions. 5. Partially purified enzyme from sporangiophores behaves in entirely similar kinetic manner as the one exhibited by the enzyme from mycelium.

Adenosine Triphosphate↗
PubMed1982

Influence of pH on the allosteric properties of lactate dehydrogenase activity of Phycomyces blakesleeanus.

1. Lactate dehydrogenase from mycelium of Phycomyces blakesleeanus showed positive homotropic interactions with NADH at all pH values studied (pH 5.0-7.7). The calculated values for the first and last intrinsic association constants remained unaltered with pH, in contrast with the Hill coefficient value, which varied significantly, reaching its maximum values at pH 6.0 and 7.7. This suggests the hypothesis that pH regulates these homotropic effects by changes in the value of the intermediate intrinsic association constants. 2. From pH 7.2 to 7.7 lactate dehydrogenase exhibited, likewise, positive homotropic interactions with pyruvate. There were practically no changes in the first and last intrinsic association constants and in Hill coefficient values with pH. At pH values below 7.2 (pH 5.0-6.8) the enzyme showed high substrate inhibition, which was highly dependent on pH, NADH concentration and temperature. By way of substrate inhibition pH regulates, primarily, lactate dehydrogenase activity towards pyruvate, since the homotropic effects appear not to be dependent on pH. 3. Fructose 1,6-bisphosphate is a true allosteric effector of lactate dehydrogenase of Phycomyces blakesleeanus. it decreases positive co-operativity with NADH, and on the other hand pyruvate co-operativity turns into mixed co-operativity. In addition, the effector decreases the inhibitory effect caused by pyruvate.

Allosteric Site↗
PubMed1981

Intracellular degradation of mitochondrial enzymes.

Quantitation of the pool of short-lived mitochondrial proteins in cultured cells by a new method shows it to be very low, i.e. approximately 1.35%. Degradation of three long-lived mitochondrial enzymes of rat liver which make up approximately 25-30% of the mitochondrial protein necessitates the cooperation of mitochondrial and lysosomal components. The degradation of carbamyl phosphate synthetase (t1/2, 7.7 d) and of ATPase (t1/2, 2-3 d) requires both a protein component from the inner mitochondrial membrane and lysosomes while degradation of glutamate dehydrogenase (GDH) (t1/2, approximately 1 d) necessitates a mitoplast factor, identified as NADP, which facilitates the inactivation by lysosomes. Chemotropic modification (carbamylation) of GDH also changes stability to rat liver proteases. All three enzymes are synthesized as pro-enzymes. Their processing and possibly control of degradation by maturases as well as the relation of both processes to molecular plasticity is presented.

Adenosine Triphosphatases↗
PubMed1981

Treatment of hyperlipoproteinemia, types II and IV, with pirifibrate: one hundred observations.

A new drug, pirifibrate, was investigated in a multicenter study of 100 patients with type IIa, IIb, or IV hyperlipoproteinemia (HLP). After one month of dieting, patients completed six months of treatment with a dose of 1,500 mg/day of pirifibrate. An average fall of about 20% in plasma cholesterol was observed in type IIa and IIb HLP, and more than 50% in the triglycerides in type IIb and IV HLP. Both reductions were statistically significant (P less than 0.00005). Increases in the alpha-lipoproteins were observed in the three types of HLP. The pre-beta-lipoproteins showed a statistically significant fall in type IIb and IV HLP. Variations observed in beta-lipoproteins were significant only in some controls with type IV, HLP, who had low basal levels.

Adolescent↗
PubMed1976

Clinical use of the "G-suit".

The "G-suit," a device for combating hypovolemic shock with external pneumatic counterpressure, represents an application of an old idea to a relatively common medical problem. Its simplicity of use and quick therapeutic effect buys time for the patient with hypovolemic shock, whether the suit is applied in the prehospital or emergency department setting.

Emergency Medical Services↗
PubMed1973

[Not Available].

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Bible↗