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J A Prieto

Publications and source records attributed to J A Prieto.

At least 37 records · Page 2Linked to original sources
PubMed1996

Combined Expression of Aspergillus nidulans Endoxylanase X24 and Aspergillus oryzae (alpha)-Amylase in Industrial Baker's Yeasts and Their Use in Bread Making.

The Aspergillus nidulans endoxylanase X24 and the Aspergillus oryzae (alpha)-amylase cDNAs were placed under the control of the Saccharomyces cerevisiae actin promoter (pACT1) and introduced into baker's yeast. Bread made with transformants expressing both enzymes (YEpACT-AMY-ACT-X24) showed a 30% increase in volume and reduced firmness in comparison with that produced with a commercial strain. Endoxylanase X24 and (alpha)-amylase seem to act synergistically to improve the quality of bread in terms of volume and density.

Journal Article↗
PubMed1996

Glucose repression may involve processes with different sugar kinase requirements.

Adding glucose to Saccharomyces cerevisiae cells growing among nonfermentable carbon sources leads to glucose repression. This process may be resolved into several steps. An early repression response requires any one of the three glucose kinases present in S. cerevisiae (HXK1, HXK2, or GLK1). A late response is only achieved when Hxk2p is present.

Carbohydrate Metabolism↗
PubMed1995

The value of exercise electrocardiography testing in the identification of coronary restenosis: a probability analysis.

We studied by means of probability analysis the role of exercise ECG in identifying coronary restenosis. A total of 213 patients were independently evaluated by clinical history, conventional assessment of the exercise ECG ('yes or no' statement), D score (a discriminant function derived from exercise ECG), and coronariography, 5.4 +/- 2.8 months after successful coronary angioplasty. The initial probability of restenosis (30%), that is, the prevalence of the condition, was radically changed by the result of clinical history (77% for patients with angina vs. 17% for those without angina). By contrast, ECG binary assessment, due to its low accuracy (70% vs 82% of clinical history, P < 0.005), was unable to significantly change the established probabilities after symptomatic evaluation. Finally, D score, which greatly enhanced specificity (92% vs. 76% of bivariate assessment, P < 0.0001), proved to be useful in changing the probability (from 32% to 76% or to 25%) of patients (n = 34) with a discordant result (no angina/positive exercise ECG). When this stepwise approach was tested in 46 new patients, predicted and observed probabilities were actually very similar. We conclude that exercise ECG has a very limited role in identifying coronary restenosis if positive responses are not adjusted with a weighted score which takes into account other exercise derived factors.

Angina Pectoris↗
PubMed1995

DOGR1 and DOGR2: two genes from Saccharomyces cerevisiae that confer 2-deoxyglucose resistance when overexpressed.

Saccharomyces cerevisiae contains two genes (DOGR1 and DOGR2) that are able to confer 2-deoxyglucose resistance when they are overexpressed. These genes are very similar, sharing 92% identity at the protein level. They code for two isoenzymes with 2-deoxyglucose-6 phosphate (2-DOG-6P) phosphatase activity. These enzymes have been purified and characterized. DogR1p shows an optimum pH of 6, an optimum temperature of 30 degrees C and a KM on 2-DOG-6P of 17 mM. DogR2p shows a similar optimum pH, but the optimum temperature is 40 degrees C and it exhibits a KM on 2-DOG-6P of 41 mM. Both enzymes require 10 mM-MgCl2 for maximal activity and they are inhibited by inorganic phosphate.

Alleles↗
PubMed1995

The expression of a specific 2-deoxyglucose-6P phosphatase prevents catabolite repression mediated by 2-deoxyglucose in yeast.

2-deoxyglucose (2-DOG), a non-metabolize analogue of glucose, is taken up by yeast using the same transporter(s) as glucose and is phosphorylated by hexokinases producing 2-deoxyglucose-6-P. We found that in DOGR yeasts, 2-DOG was not able to trigger glucose repression, even at concentrations of 0.5%. This result suggests that the specific 2-DOG-6P phosphatase, the enzyme responsible for the DOGR phenotype, may be involved in inhibiting the process of catabolite repression mediated by 2-DOG.

Deoxyglucose↗
PubMed1995

A randomized trial of prophylactic doxycycline for curettage in incomplete abortion.

OBJECTIVE: To determine whether prophylactic doxycycline at suction curettage for incomplete abortion decreases the rate of postoperative pelvic infection. METHODS: We randomized 240 patients to receive intravenous doxycycline or placebo at curettage. Cervical specimens for gonorrhea and chlamydia were obtained preoperatively. Two weeks post-procedure, we evaluated all patients for infectious morbidity and repeated gonorrhea and chlamydia cultures. Statistical analysis used Mann-Whitney U test, McNemar test, or Fisher exact test, as appropriate. RESULTS: There were no statistically significant differences in age, parity, gestational age, history of sexually transmitted disease, pelvic inflammatory disease, or multiple sex partners between the doxycycline and placebo groups. Preoperative gonorrhea or chlamydia isolates were positive in five (4.2%) and six (5%) of 120 doxycycline patients and four (3.3%) and eight (6.6%) of 120 controls (not significant). All preoperative gonorrhea isolates remained positive postoperatively. Seven (5.8%) controls had positive postoperative chlamydia isolates, as did one (0.8%) in the doxycycline group (P = .06). We diagnosed eight (6.6%) of 120 doxycycline patients and seven (5.8%) of 120 controls with infectious morbidity (not significant). CONCLUSION: In our population of patients with incomplete abortion, the prevalence of gonorrhea and chlamydia was low, and prophylactic doxycycline did not decrease the rate of postoperative febrile morbidity.

Abortion, Incomplete↗
PubMed1995

Coagulation studies in patients with marked thrombocytopenia due to severe preeclampsia.

From July 1, 1990, to July 1, 1993, we analyzed the results of fibrinogen levels, prothrombin time, and partial thromboplastin time in patients with severe preeclampsia, at least one platelet count less than 100,000/microL, and no signs of abruption or hemorrhage. Analysis was by Pearson's correlation coefficient and Wald's sequential analysis. We analyzed 162 blood collections from 48 patients. There was no correlation between the level of thrombocytopenia and the levels of prothrombin time, partial thromboplastin time, or fibrinogen. None of the samples from any of the preeclamptic patients demonstrated an abnormal prothrombin time or partial thromboplastin time.

Blood Coagulation↗
PubMed1994

Nucleotide sequence of a putative peroxisomal protein from the yeast Lipomyces kononenkoae.

A cDNA corresponding to a putative peroxisomal protein from the yeast Lipomyces kononenkoae has been isolated. It contains an ORF of 498 bp that predicts a polypeptide of 166 amino acids with an apparent molecular mass of 17,365 Da. The protein shares a high degree of homology with proteins associated to the peroxisomal membrane of Candida boidinii.

Amino Acid Sequence↗
PubMed1994

Molecular characterization of a gene that confers 2-deoxyglucose resistance in yeast.

We have isolated a gene whose expression enables yeast cells to overcome the inhibition of growth produced by the presence of 2-deoxyglucose. The gene contains an open reading frame of 738 bp that may code for a protein of 27,100 Da. Cells carrying this gene contain high levels of a specific 2-deoxyglucose-6-phosphate phosphatase. The expression of this phosphatase is increased by the presence of 2-deoxyglucose and is constant along the growth curve.

Amino Acid Sequence↗
PubMed1993

Association of clinical intra-amniotic infection and meconium.

The objective of this study was to determine the rate of intra-amniotic infection in patients with meconium-stained amniotic fluid compared to controls. With a retrospective case-controlled study design, we compared 100 pregnant women with meconium to 100 pregnant women without meconium for the development of intra-amniotic infection. Patients delivered between September 1 and December 31, 1990. Exclusion criteria were active infection prior to labor or antibiotic use within the 7 days prior to delivery. We diagnosed clinical intra-amniotic infection in patients with ruptured membranes by a maternal temperature 100.4 degrees F or higher and any two of the following: maternal or fetal tachycardia, uterine tenderness, white blood cell count 10,500 mm3 or more, or foul-smelling amniotic fluid. Demographic variables, labor characteristics, maternal infectious morbidity, and neonatal outcome were analyzed using the Wilcoxin rank test, chi-square test, or Fisher's exact test as appropriate. The rate of clinical intra-amniotic infection was significantly higher in women with meconium-stained amniotic fluid (8%) compared with women with no meconium (2%) (p = 0.05).

Adult↗
PubMed1993

Significant coronary restenosis limits the recovery of regional left myocardial dysfunction achieved after successful coronary angioplasty.

Impaired regional left ventricular function has been shown to improve after successful transluminal coronary angioplasty, but there are no data concerning the effect of coronary restenosis on this recovery. Therefore, the short- (1 month) and midterm (5.5 months) evolution of systolic regional left ventricular function was prospectively investigated in 41 patients undergoing successful coronary angioplasty. In patients with resting hypokinetic areas before angioplasty and no restenosis (n = 8), regional function improved from -6.0 +/- 2.9 to -2.9 +/- 2.4 SD/segment (P < 0.01) in the short-term, without further significant changes at mid-term. Patients with hypokinetic areas and coronary restenosis > or = 70% (n = 15) also showed early functional recovery from -5.1 +/- 2.2 to -1.4 +/- 2.5 SD/segment (P < 0.00001) but, in contrast with the other subset of patients, a significant reduction to -3.9 +/- 2.3 SD/segment (P < 0.0001) was observed at mid-term. In spite of this, regional function was still better than before angioplasty (P < 0.01). No significant changes were observed in patients without either asynergy or restenosis (n = 16). The small number of cases without preliminary hypokinesis and development of restenosis > or = 70% (n = 2) precluded an analysis of this situation, but a new and severe hypokinetic defect was recognized in one patient in a later study. We conclude that the improvement in regional myocardial function observed early after successful dilation of the culprit vessel is partially lost when significant restenosis develops.

Adult↗
PubMed1993

[Probability analysis of the value of ergometry in the detection of restenosis after coronary angioplasty].

To evaluate the usefulness of treadmill exercise test in the diagnosis of coronary restenosis, we have chosen a sequential and probabilistic analysis. The rate of coronary restenosis found in the sample (n = 213) was of 30%. This initial probability of having restenosis was radically changed by the recurrence of typical angina: 77% in patients with this symptom, 17% in those without (p < 0.001). In contrast, the qualitative result of the exercise test was unable to change significantly the probabilities established after anamnesis. This was due to a lower specificity for exercise test (76%) than for angina (93%), the sensibility being the same (56%) for both. Employment of a discriminant value that integrates different ergometric variables did not enhanced sensibility, but allowed the identification of a good number of false positive results and therefore palliated the negative impact of faulty specificity. Being applied to a "discordant group" (no angina/positive exercise test, n = 34) was able to achieve a significant change in probability: from 15% to 50% or 4% (p < 0.01), according to the discriminant being lesser or greater than a preestablished value. In conclusion, prevalence of the event and evaluation of symptomatology are both important to estimate the probability of suffering coronary restenosis. On the contrary, exercise test, in the absence of a weighty method, adds more confusion than clarity to the analysis of the problem. Our results can be used to improve the follow-up of patients who have been successfully dilated by angioplasty.

Angioplasty, Balloon, Coronary↗
PubMed1991

Success determining factors in percutaneous transluminal balloon valvuloplasty of pulmonary valve stenosis.

Twenty-two percutaneous transluminal balloon valvuloplasty procedures were performed on 21 patients with congenital pulmonary valve stenosis. The peak systolic pressure gradient was immediately reduced from 79.1 +/- 7.4 to 22.2 +/- 1.8 mmHg, (P less than 0.0001) and follow-up cardiac catheterization at 5.3 +/- 0.4 months in 19 patients revealed no further significant change in gradient (23.5 +/- 3.2 mmHg). The best results were obtained when balloons larger than the pulmonary annulus were used, i.e. an immediate residual transvalvular gradient of 22.0 +/- 2.2 mmHg with a balloon/annulus ratio greater than 1, as opposed to 44.2 +/- 5.4 with a balloon/annulus ratio = 1 (P less than 0.001). The angiographically determined cusp thickness of the stenotic pulmonary valves was significantly greater than that of the control group of 24 patients without pulmonary valve stenosis (1.21 +/- 0.09 vs 0.59 +/- 0.02 mmHg, P less than 0.00001). The relationship between this parameter and the residual transvalvular gradient at follow-up was found to be significant (r = 0.77, P less than 0.001). It is concluded that balloon size is a determinant factor in achieving good results with percutaneous balloon valvuloplasty although cusp thickness, a factor to which scant regard has hitherto been paid, also plays a significant role in the residual transvalvular gradient measured at follow-up.

Adolescent↗
PubMed1989

Positive modulators of muscle acetylcholine receptor.

A solution of succinic anhydride (SA) in buffer N-tris(hydroxymethyl)methyl-2-aminoethane sulfonic acid (TES), the SATES solution, potentiates the effect of carbonyl containing agonists on frog muscle (del Castillo et al., Br. J. Pharmac. 84: 275-288, 1985). Here we report that the main compound in the SATES solution is a monosuccinyl ester of TES (MST). This compound is not an agonist of the acetylcholine (ACh) receptor nor is it an inhibitor of ACh esterase, yet MST potentiates the ACh-induced tension and depolarization in frog muscle to a new maximum. It increases the amplitude of miniature endplate potentials but has no effect on the time course of miniature endplate currents. The acetylated analogue of MST (mono-acetyl-TES: MAT) had similar but more pronounced effects on frog muscle. Neither MST nor MAT affect [3H]Ach binding to receptor-rich membranes from the electric organ of Torpedo californica, or the affinity state transition induced by agonists. Radiolabeled MST does not bind to these membranes and MAT does not alter agonist-induced ion flux. Therefore, these compounds seem to act as positive modulators of muscle ACh receptor but are inactive in Torpedo vesicles.

Acetylcholine↗
PubMed1989

[Diverticulum of the right ventricle].

We report the case of a 38-year-old woman who underwent cardiac catheterization because of cyanosis from birth. This study revealed a right ventricular cavity hypoplasia, an atrial septal defect, and a diverticulum originated from the free right ventricular wall. Ventricular diverticuli, especially those in the right ventricle, are very rare malformations, usually associated with other cardiac defects. The right ventricular diverticulum is generally non-symptomatic, diagnosed by chance, and does not usually require surgical treatment.

Adult↗
PubMed1989

[Quantitative evaluation of the exercise test using discriminant analysis].

One hundred and twenty seven selected patients had treadmill tests and coronary angiograms. Eight variables were correlated by discriminant analysis to the presence and extent of coronary artery disease (CAD) in a two-way approach. In the first (43 patients without significant CAD versus 84 with significant CAD), two ergometric (maximal heart rate achieved and exercise time) and two common (age and sex) variables merged as predictors. In the second approach (65 patients without CAD or CAD with a little amount of myocardium at risk versus 62 with CAD and a greater extent of jeopardized myocardium), the two clinical variables were replaced by two new ergometric predictors: the level of ST depression and maximum systolic blood pressure reached. Comparatively with the conventional assay of exercise test, the second discriminant function (Z2) enhanced specificity (67 versus 84%) but impaired sensibility (82 versus 70%); nevertheless, this late index was preserved (93 versus 89%) in the 3-vessel CAD group. Moreover, the Z2 value decreased as the severity of CAD increased; the differences between groups were significant (p less than 0.01) up to the level of 2-vessel versus 3-vessel CAD where the trend persists but failed to be significant. Likewise, within the 1-vessel CAD group, the mean Z2 value was lower (p less than 0.01) when the narrowing was located in the proximal portion of the left anterior descending coronary artery. This quantitative approach to the exercise test was validated in a new series of 85 patients and, in our opinion, could be useful for making patient care decisions.

Angiocardiography↗
PubMed1983

Increased thymic hormone responsive suppressor T lymphocyte function in chronic active hepatitis.

Mitogen-induced suppressor T lymphocyte function was evaluated in patients with chronic active hepatitis (CAH). The in vitro effect of the biological response modifier, thymosin fraction 5, on the suppressive activity of peripheral blood mononuclear cells (PBM) was also assessed. Suppressor cell activity was significantly decreased in patients with CAH when compared to controls (P less than 0.001). In the absence of the inducing mitogen, thymosin-treated PBM from both patients and controls promoted enhancement of tritiated thymidine uptake by cocultured allogeneic lymphocytes. When thymosin-treated mononuclear cells were mitogen-activated; patients, but not the controls, showed a marked increase in suppressor activity (P less than 0.001). These results indicate that the polypeptides contained in thymosin fraction 5 can promote a helper effect in patients and controls. Furthermore, PBM from patients with CAH contain a subset of lymphocytes that can express a suppressive function following thymosin treatment. We conclude that thymosin fraction 5 can promote an in vitro restoration of suppressor T cell function in patients with CAH.

Adolescent↗