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J Soler

Publications and source records attributed to J Soler.

At least 181 records · Page 10Linked to original sources
PubMed1988

Partial characterization of intracellular protease activity which participates in the inactivation of carbamyl phosphate synthase in Phycomyces blakesleeanus.

We have partially characterized an intracellular fraction from Phycomyces blakesleeanus which shows proteolytic activity. The apparent thermal inactivation constant (Kd) was 0.12 min-1 at 50 degrees C. This proteolytic fraction was split into two active fractions by ultrafiltration using a membrane with an exclusion size of 30,000. Both fractions were inhibited by phenyl methyl sulphonyl fluoride. The Ki value for the fraction with molecular weight greater than 30,000 was 0.075 mM. The fraction with molecular weight less than 30,000 inactivated the Phycomyces CPS.

Carbamoyl-Phosphate Synthase (Ammonia)↗
PubMed1988

[Actinic reticuloid. Immunohistochemical study].

A patient that fulfilled the clinical and histological features of actinic reticuloid has been studied. He presented a positive patch test for fragance mix. Typical cutaneous lesions were reproduced with a solar simulator. The immunochemical studies of the inflammatory infiltrates of these induced lesions gave a higher percentage of T8 in relationship to T4 lymphocytes. Most of the cells were HLA-DR positive. No clonality of these lymphocytes was detected. In the peripheral blood lymphocytes, an increased percentage of T8 lymphocytes was also observed.

Exudates and Transudates↗
PubMed1987

Effect of light on several metabolites of carbohydrate metabolism in Phycomyces blakesleeanus.

The concentrations of all metabolites studied, except fructose 1,6-bisphosphate from wild-type Phycomyces blakesleeanus, were light dependent. This photoregulation appears to be independent of the mad gene product(s) and also independent of carotene biosynthesis regulation. However, the photoregulation of glyceraldehyde 3-phosphate, 2-phosphoglycerate, and phosphoenolpyruvate may be assigned to these mad and car S gene products.

Carbohydrate Metabolism↗
PubMed1986

A study of the allosteric kinetics of Phycomyces pyruvate kinase as judged by the effect of L-alanine and fructose 1,6-bisphosphate.

The influence of fructose 1,6-bisphosphate and L-alanine on the kinetics of pyruvate kinase (ATP:pyruvate O2-phosphotransferase, EC 2.7.1.40) from Phycomyces blakesleeanus NRRL 1555 (-) was studied at pH 7.5. By addition of fructose 1,6-bisphosphate the sigmoid kinetics with respect to phosphoenol pyruvate and Mg2+ were abolished and the velocity curves became hyperbolic. In the presence of L-alanine the positive homotropic cooperativity with respect to phosphoenol pyruvate increased with Hill coefficient values close to 4, while the sigmoid kinetics with respect to Mg2+ became hyperbolic. Fructose 1,6-bisphosphate overcomes the inhibition produced by L-alanine, the antagonism between phosphoenol pyruvate and L-alanine also being evident. Inhibition has been found at high Mg2+ concentrations, compatible with the binding of the magnesium ions to an inactive conformational state of the enzyme. The data were analysed on the basis of the two-states concerted-symmetry model of Monod, Wyman and Changeux, and the parameters of the model were calculated. Phosphoenol pyruvate and fructose 1,6-bisphosphate appeared to show exclusive binding to the active conformational state (R), whereas magnesium ions bind preferentially, by a factor of 45, to the R state. L-Alanine binds more readily to the inactive T state of the enzyme.

Alanine↗
PubMed1986

Systolic compression of coronary artery in hypertrophic cardiomyopathy.

To determine the prevalence and significance of the systolic compression of the anterior descending coronary artery in hypertrophic cardiomyopathy, we studied 54 consecutive patients out of a catheterization laboratory population of 1619. This angiographic finding was found to be more prevalent (P less than 0.001) and severe in myopathic than in secondary hypertrophy. Complete systolic occlusion occurred in 5 of the 6 patients with nonobstructive cardiomyopathy showing the systolic narrowing. Severe septal squeezing was also present in these cases and the diastolic time lag to refill the distal branches reached 20-33% of the diastolic period. This subset of patients showed the least dynamic anterior wall contraction (P less than 0.001) and the highest incidence of thallium-201 perfusion defects (P less than 0.05) and of recurrent cardiac arrest (P less than 0.05). We conclude that severe systolic compression of the descending coronary artery in hypertrophic cardiomyopathy may be an angiographic marker of the myopathic hypertrophy extending to the anterior wall and might contribute to ischemia when the time to restore the distal perfusion is greatly delayed.

Adolescent↗