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E Molina

Publications and source records attributed to E Molina.

At least 19 recordsLinked to original sources
PubMed1992

The interactive effects of dietary quality on the growth and attained size of young Mexican children.

Predictors of attained size at 30 mo and growth rate between 18 and 30 mo (eg, diet, maternal size, morbidity, age at weaning, and selected environmental factors) were investigated by using longitudinal data from 67 Mexican children aged 18-30 mo. These children were small because of growth stunting in early infancy. Between 18 and 30 mo they grew on average at the 50th percentile of National Center for Health Statistics references values for weight, and the 25th for length. Size at 30 mo and growth rates were unrelated to energy or protein intakes during the previous year, but positively related to consumption of animal-origin foods. Maternal weight predicted size and growth only for children with larger intakes of animal products. Individual rates of weight and length growth were uncorrelated on average, correlated negatively when animal-product intake was low, and positively only when more animal products were consumed. Integrated weight and length growth, and the influence of maternal size on growth, may be disrupted by poor dietary quality. Different children would be identified as malnourished depending on whether weight or length growth was measured.

Analysis of Variance↗
PubMed1992

Field evaluation of an enzyme-linked immunosorbent assay for estimating the sporozoite rate in Anopheles albimanus.

We have verified for specimens of Anopheles albimanus that an enzyme-linked immunosorbent assay (ELISA) used to assess Plasmodium vivax and P. falciparum sporozoite antigen rates gives results comparable to the salivary gland dissection method for estimating sporozoite rates. For 14,150 adults of An. albimanus, captured at five locations in Guatemala, we report sporozoite antigen rates of 0.03-0.57%, which correlate with the malaria prevalences at the study sites. We also present data that suggest that specimens of An. albimanus for the ELISA can be obtained more efficiently by cattle corral collections than by the human bait capture method.

Animals↗
PubMed1991

Heterogeneity of rat liver cytosol casein kinase 2. Association between the alpha/alpha' -subunits of casein kinase 2 and the phosphorylatable protein pp49.

Casein kinase 2 activity could be resolved into three peaks by chromatography on DEAE-Sepharose. The peak eluted at high salt concentrations (casein kinase 2b) showed molecular and kinetic properties typical of the heterotetramer composed of alpha-(or alpha'-) and beta-subunits. In contrast, the peak that was eluted at low salt concentrations (casein kinase 2a) contained no beta-subunit but a phosphorylatable protein of 49 kDa (pp49), in addition to the alpha/alpha'-subunits. The presence of alpha/alpha'/alpha"-subunits in preparations of casein kinases 2a and 2b was confirmed by immunological assays. Casein kinase 2a had low specific activity and a very high apparent Km for beta-casein. The peak eluted at intermediate ionic strength contained the alpha/alpha'-subunits and variable amounts of beta-subunit and pp49, and had kinetic properties intermediate between those of casein kinases 2a and 2b. Experiments based on heat inactivation, inhibition by low concentrations of heparin and ability to use GTP as substrate suggested that phosphorylation of pp49 was catalysed by the alpha/alpha'-subunits of casein kinase 2. No similarities were observed in the phosphopeptide maps of pp49 and beta-subunit. These results show that the alpha/alpha'-subunits of rat liver cytosol casein kinase 2 can form complexes not only with the beta-subunit but also with pp49, and that the complexes containing pp49 have a reduced affinity for the exogenous protein substrate beta-casein.

Animals↗
PubMed1991

Comparison of rubidium-82 positron emission tomography and thallium-201 SPECT imaging for detection of coronary artery disease.

The diagnostic performance of rubidium-82 (Rb-82) positron emission tomography (PET) and thallium-201 (Tl-201) single-photon emission-computed tomography (SPECT) for detecting coronary artery disease was investigated in 81 patients (52 men, 29 women). PET studies using 60 mCi of Rb-82 were performed at baseline and after intravenous infusion of 0.56 mg/kg dipyridamole in conjunction with handgrip stress. Tl-201 SPECT was performed after dipyridamole-handgrip stress and, in a subset of patients, after treadmill exercise. Sensitivity, specificity and overall diagnostic accuracy were assessed using both visually and quantitatively interpreted coronary angiograms. The overall sensitivity, specificity and accuracy of PET for detection of coronary artery disease (greater than 50% diameter stenosis) were 84, 88 and 85%, respectively. In comparison, the performance of SPECT revealed a sensitivity of 84%, specificity of 53% (p less than 0.05 vs PET) and accuracy of 79%. Similar results were obtained using either visual or quantitative angiographic criteria for severity of coronary artery disease. In 43 patients without prior myocardial infarction, the sensitivity for detection of disease was 71 and 73%, respectively, similar for both PET and SPECT. There was no significant difference in diagnostic performance between imaging modalities when 2 different modes of stress (exercise treadmill vs intravenous dipyridamole plus handgrip) were used with SPECT imaging. Thus, Rb-82 PET provides improved specificity compared with Tl-201 SPECT for identifying coronary artery disease, most likely due to the higher photon energy of Rb-82 and attenuation correction provided by PET. However, post-test referral cannot be entirely excluded as a potential explanation for the lower specificity of Tl-201 SPECT.

Adult↗
PubMed1991

Dissociation of the hepatic insulin receptor favours its phosphorylation by casein kinase 2.

The alpha beta heterodimeric form of untreated hepatic insulin receptor was a substrate for casein kinase 2, whereas the alpha 2 beta 2 heterotetramer was not. On the contrary, autophosphorylation was detected only in the heterotetramer. Dissociation of the receptor by treatment with dithiothreitol decreased its autophosphorylation but favoured phosphorylation of its beta-subunit by casein kinase 2.

Animals↗
PubMed1991

Quantitative evaluation of regional substrate metabolism in the human heart by positron emission tomography.

Meaning interpretation of metabolic images obtained by positron emission tomography for evaluation of cardiac disease requires a knowledge of the normal variation in regional myocardial substrate metabolism. Recent studies with fluorine-18 (F-18) fluorodeoxyglucose suggest inhomogeneity of myocardial glucose metabolism in the normal human heart, which may relate to substrate availability. Therefore, quantitative evaluation of myocardial oxidative metabolism and glucose metabolism, as derived by dynamic positron emission tomography with carbon-11 (C-11) acetate and F-18 fluorodeoxyglucose, was performed in nine healthy male volunteers. All were studied under tightly controlled metabolic conditions of hyperinsulinemic-euglycemic clamping with and without a concurrent lipid emulsion infusion. Significant inhomogeneity of regional glucose metabolism was noted although it was less than that described under fasting conditions. Glucose utilization was 13% lower in the septum compared with the lateral wall both without and with lipid infusion (0.34 vs. 0.39 mumol/g per min, respectively, p less than 0.05; and 0.33 vs. 0.38 mumol/g per min, respectively, (p less than 0.05). Relatively decreased septal glucose utilization could not be explained by decreased metabolic demand because C-11 clearance constants were marginally higher in the septum than in the lateral wall in both studies (0.055 vs. 0.054 per min, respectively, p = NS; and 0.061 vs. 0.056 per min, respectively, p less than 0.05). Relatively decreased septal glucose utilization could reflect regional variation in substrate use and possible preferential free fatty acid utilization by the septum. These data provide a useful framework for assessing altered cardiac metabolism in disease and support standardization of metabolic conditions during metabolic imaging with positron emission tomography.

Acetates↗
PubMed1991

[Obstructive sleep apnea syndrome in childhood: study of three cases].

We report three children with obstructive sleep apnea syndrome, two secondary to pharyngeal obstruction and the third secondary to laryngomalacia. All patients presented important respiratory efforts with inspiratory stridor during sleep, frequent obstructive apneas with important hipoxemia, sweating, and arousal episodes. Two patients suffered excessive daytime sleepiness, behavioral disturbances and development delay, and the third, intelligence in the borderline retardation range, and important heart arritmias (bradycardia with ventricular extrasystoles) during obstructive apneas. In two children the Obstructive Sleep Apnea Syndrome and the secondary symptoms disappeared after adenotonsillectomy. The patient with laryngomalacia required tracheostomy.

Adenoidectomy↗
PubMed1990

Noninvasive evaluation of sympathetic nervous system in human heart by positron emission tomography.

The noninvasive functional characterization of the cardiac sympathetic nervous system by imaging techniques may provide important pathophysiological information in various cardiac disease states. Hydroxyephedrine labeled with carbon 11 has been developed as a new catecholamine analogue to be used in the in vivo evaluation of presynaptic adrenergic nerve terminals by positron emission tomography (PET). To determine the feasibility of this imaging approach in the human heart, six normal volunteers and five patients with recent cardiac transplants underwent dynamic PET imaging after intravenous injection of 20 mCi [11C]hydroxyephedrine. Blood and myocardial tracer kinetics were assessed using a regions-of-interest approach. In normal volunteers, blood 11C activity cleared rapidly, whereas myocardium retained 11C activity with a long tissue half-life. Relative tracer retention in the myocardium averaged 79 +/- 31% of peak activity at 60 minutes after tracer injection. The heart-to-blood 11C activity ratio exceeded 6:1 as soon as 30 minutes after tracer injection, yielding excellent image quality. Little regional variation of tracer retention was observed, indicating homogeneous sympathetic innervation throughout the left ventricle. In the transplant recipients, myocardial [11C]hydroxyephedrine retention at 60 minutes was significantly less (-82%) than that of normal volunteers, indicating only little non-neuronal binding of the tracer in the denervated human heart. Thus, [11C]hydroxyephedrine, in combination with dynamic PET imaging, allows the noninvasive delineation of myocardial adrenergic nerve terminals. Tracer kinetic modeling may permit quantitative assessment of myocardial catecholamine uptake, which will in turn provide insights into the effects of various disease processes on the neuronal integrity of the heart.

Adult↗
PubMed1990

[Complicated hepatic hydatid cyst and acute pancreatitis. Value of ERCP and treatment with endoscopic sphincterotomy].

We present the case of a 29 year-old cholecystectomized woman with hepatic hydatid cysts who was admitted for acute pancreatitis. Echography and abdominal CAT revealed three thydatid cysts-the one in the right liver lobe being complicated-as well as pancreatitis. Endoscopic retrograde cholangiopancreatography (ERCP) confirmed the suspected diagnosis of intrabiliary hydatid cyst rupture. An endoscopic sphincterotomy was performed, posterior evolution being asymptomatic, thus permitting the postponing of surgery.

Adult↗
PubMed1990

[Haemophilus influenzae carriers among child care personnel: its prevalence and the efficacy of enoxacin in its elimination].

In a previous study we observed that 6% of adult and 18% of children contacts of H. influenzae infected patients became carriers of the bacillus. We studied 1296 adults involved in children care, 398 from day care centers and 898 from hospitals in Santiago. A pharyngeal sample was cultured in chocolate agar plus bacitracin (300 mg/ml) and incubated at 37 degrees C in a 5-10% CO2 atmosphere for 18-24 h. Isolates of H influenzae were biotypified and serogrouped according to international recommendations. We observed that 2.4% of subjects were H influenzae carriers. Thirty carriers were treated with 2 doses of enoxacin, 440 mg. All became free of H influenzae at a 30-day follow-up.

Adult↗
PubMed1990

Three-dimensional assessment of myocardial oxidative metabolism: a new approach for regional determination of PET-derived carbon-11-acetate kinetics.

We have developed a new analysis algorithm which generates polar coordinate maps of myocardial carbon-11-(11C) acetate kinetics. In 10 normal subjects (n = 20 studies), myocardial 11C clearance rate constants (k) averaged 0.057 +/- 0.009 (per minute). Regional k-values varied only 10.6 +/- 2.4% in the normal left ventricle. However, there was a small but significant segmental variation with increased 11C clearance in the septal, anterior, and basal regions (p less than 0.05). Since 11C clearance rates reflect tri-carboxylic acid cycle flux, these results suggest that myocardial oxidative metabolism is relatively homogeneous in the normal human heart at rest with minor regional variations, which possibly reflect varying regional wall stresses or substrate utilization. The proposed approach provides three-dimensional evaluation of regional oxidative metabolism which will permit characterization of the location, extent, and severity of myocardial disease.

Acetates↗
PubMed1990

McCune-Albright syndrome: the patterns of scintigraphic abnormalities.

This study of 22 patients with the McCune-Albright syndrome examined the scintigraphic distribution of fibrous dysplasia. The most frequently affected areas were the base of the skull (82% of patients), mandible (50%), facial bones (45%), femora (59%), and legs (64%). The least frequently affected areas included the hands (none), wrists (none), ankles (none), feet (5%), sacrum (5%), and vertebrae (9%). The distribution varied somewhat from idiopathic fibrous dysplasia but generally agreed with the distributions reported in radiographic studies of patients with the McCune-Albright Syndrome. The serum alkaline phosphatase was not an accurate predictor of the extent of fibrous dysplasia.

Bone and Bones↗
PubMed1989

An office-based exercise protocol for predicting chronotropic response of activity-triggered, rate-variable pacemakers.

Activity-triggered, rate-variable pacing systems offer a wide range of pacemaker patients the benefits of an appropriate paced chronotropic response. However, optimizing settings for these devices often entails treadmill exercise testing. To assess simpler procedures for predicting appropriate settings, pacing rates of "strapped-on" and implanted Activitrax pacemakers were evaluated during arm exercise, walk-in-place exercise and treadmill exercise (0% slope at 1.5, 2.0 and 3.0 mph). For exercise of similar duration, steady-state pacing rates of implanted devices during arm and walk-in-place exercise were lower than those achieved during treadmill exercise. Linear regression analysis resulted in the slope of these relations most closely approaching 1.0 for arm exercise at "low" activity threshold, while walk-in-place tended to result in slopes approaching 1.0 at all activity thresholds. Similarly, although strapped-on devices underestimated rates obtained with implanted devices, differences fell within a narrow range (-6 to -14%). Thus, in patients with implanted or strapped-on Activitrax pacemakers, relatively simple exercise procedures suitable for office or clinic environment may be useful to provide an estimate of pacing rates during physical activity, and may thereby facilitate selection of appropriate programmable settings.

Adult↗
PubMed1989

[Conservative treatment of urethral stenosis in childhood].

During a 19 years period (1969-March 1988) 22 children presented for treatment of urethral strictures. The patients ranged in age from neonatal period to 13 years old, 20 of them were boys and 2 girls. We have found 3 congenital cases, 5 traumatic cases, 9 inflammatory (versus infections) cases and 5 iatrogenic cases. Diagnosis can be suspected from the history and physical examination (voided stream), and confirmed radiographically and endoscopically; we have employed urodynamics studies in 2 cases, and those have seem of much important the follow-up. Treatment is controversial between different authors. In ours series progressive dilatation procedure have been elective (retrograde swelling catheter versus anterograde swelling catheter with cytostomy), with 86.3% of good results.

Adolescent↗
PubMed1989

[Hernial strangulation of Meckel's diverticulum: Littre's hernia. Apropos of 4 cases].

Hernial strangulation of Meckel's diverticulum (Littre's hernia) is a rare anatomoclinical form. It represents 10% of all complications of Meckel's diverticulum (8.8% of our cases), and complications like hemorrhage, perforation and diverticulitis are fairly frequent. Four cases of Littre's hernia are presented: two males and two females, with an average age of 67 years (range 50-83 years), representing 0.08% of all the inguinal-crural hernias operated in the department. The clinical manifestations were those of intestinal obstruction because a mixed type Littre's hernia was involved, with compromise of the diverticulum and its intestinal loop. Preoperative diagnosis is unlikely in strangulation without disturbances in the intestinal transit and, in fact, is even less likely if it is accompanied by obstruction. The diagnosis is thus almost always intraoperative. The correct treatment is surgery after restoring the patient's hemodynamic equilibrium. Simple and/or loop diverticulectomy via herniotomy, herniolaparotomy or laparotomy are debated. We think that this disorder can generally be resolved using the inguinal approach, as in any strangled hernia, with the technical option of using a larger, more comfortable and safer approach in cases of important obesity and/or deterioration of the loop (necrosis, perforation). In elderly patients with uncomplicated Littre's hernia and Meckel's diverticulum, abstention from diverticular exeresis may be justifiable. Of the four patients, the first two died from cardiogenic shock and pulmonary embolism, respectively; the last two evolved well (except for a wound abscess).

Aged↗