Decreased serum ubiquinone-10 concentrations in phenylketonuria.

BACKGROUND: Ubiquinone-10 is a lipid with important metabolic functions that may be decreased in phenylketonuria (PKU) because patients with PKU consume diets restricted in natural proteins. OBJECTIVE: We studied serum ubiquinone-10 concentrations in PKU patients. DESIGN: This was a retrospective, transversal study in which we compared serum ubiquinone-10, plasma cholesterol, plasma tyrosine, and plasma phenylalanine concentrations in 43 PKU patients with concentrations in a reference population (n = 102). Serum ubiquinone-10 concentrations were analyzed by HPLC with ultraviolet detection. Plasma tyrosine and phenylalanine were measured by ion-exchange chromatography. RESULTS: Serum ubiquinone-10 concentrations in PKU patients were significantly lower than in the reference population (P < 0.01 for patients aged 1 mo to <8 y and P < 0.00005 for patients aged 8-33 y). Moreover, 5 of 18 PKU patients (28%) in the younger age group and 10 of 23 (43%) in the older age group had serum ubiquinone-10 concentrations below the reference interval. CONCLUSIONS: Serum ubiquinone-10 deficiency appears to be related to the restricted diet of PKU patients. Because serum ubiquinone-10 plays a major antioxidant role in the protection of circulating lipoproteins, the correction of ubiquinone-10 concentrations should be considered in PKU patients. Further investigation seems advisable to elucidate whether the deficiency in serum ubiquinone-10 status is clinically significant.     

An interdisciplinary national program developed at Baylor to make science exciting for all K-5 students.

The achievement gap in science begins in elementary school, where many students lose interest in science-related studies, particularly students from traditionally underrepresented groups. The "My Health My World" Project (hereafter, "the Project"), developed at Baylor College of Medicine with the assistance of federal funds, is a national effort to address this problem. The Project's goals are to make science appealing and relevant for elementary school students (i.e., kindergarten through grade five), including those from underrepresented minorities (URMs), and easy to teach for teachers and parents. It is achieving this goal by the development of interdisciplinary instructional materials that use environmental health issues as a unifying theme. The Project provides its materials (including take-home materials for parents) and training for teachers at seven dissemination centers across the country, established in 1997. Workshops are also held to train facilitators, chosen from among local science education leaders, who in turn hold workshops to train other teachers. Each center receives a mini-grant to cover costs related to the training it provides, and all coordinate their training to offer comparable experiences for all participants. Field tests in 1995, 1996, and 1997 involving culturally, racially, and ethnically diverse students and teachers in two sites indicate that the participating teachers found that the Project's materials promote science learning and enthusiasm for science and are easy to use and engaging for teachers. Ratings for workshops in 1998 were also high for all characteristics evaluated. All signs after the Project's first full year of dissemination activities (1998) indicate that it will continue to reach more teachers and students across the nation and will eventually help more students from all backgrounds achieve in science-related studies.     

Subjective versus statistical model assessment of mortality risk in open heart surgical procedures

BACKGROUND: The aim of this study was to compare the predictive accuracy for open heart surgical mortality between a statistical model based on collection of clinical data and surgeons' subjective risk assessment. METHODS: Predictive discrimination of both risk assessments (surgeons' and model) was compared through the area under the receiver operating characteristic curve. Logistic regression analysis was used to assess the relation between surgeons' and model predictions to actual outcomes. Calibration of the subjective estimates was evaluated with a chi2 test. RESULTS: Overall, the area under the receiver operating characteristic curve was 0.76 for the statistical model and 0.70 for the subjective assessment. Logistic regression analysis showed that the statistical model remained significant after accounting for the subjective assessment. Calibration of subjective mortality predictions was poor. CONCLUSIONS: Surgeons' risk assessment tends to cluster in the middle ranges of risk. Subjective assessment seems accurate in identifying the two extremes of risk but is inaccurate for intermediate risk levels. A multivariate statistical model improves the accuracy of subjective predictions.     

Specific prognostic factors for secondary pancreatic infection in severe acute pancreatitis

BACKGROUND/AIMS: The aim of the present study was to investigate whether there are specific prognostic factors to predict the development of secondary pancreatic infection (SPI) in severe acute pancreatitis in order to perform a computed tomography-fine needle aspiration with bacteriological sampling at the right moment and confirm the diagnosis. METHODS: Twenty-five clinical and laboratory parameters were determined sequentially in 150 patients with severe acute pancreatitis (SAP) and univariate, and multivariate regression analyses were done looking for correlation with the development of SPI. RESULTS: Only APACHE II score and C-reactive protein levels were related to the development of SPI in the multivariate analysis. A regression equation was designed using these two parameters, and empiric cut-off points defined the subgroup of patients at high risk of developing secondary pancreatic infection. CONCLUSION: The results showed that it is possible to predict SPI during SAP allowing bacteriological confirmation and early treatment of this severe condition.     

Smoking in pregnancy: A survey from Northern Italy

Summary The prevalence of smoking in pregnancy was analyzed in a survey of women delivering between January and March 1989 in a large maternity clinic in Milan, Northern Italy. Out of the 528 women interviewed, 183 (35%) were current smokers before pregnancy and 99 stopped smoking during pregnancy. The probability of stopping smoking decreased with increasing age and was lower in less educated women, but these findings were not statistically significant. Considering persistent smokers only, the mean number of cigarettes per day fell from 13 before to 8 during pregnancy; this reduction was generally consistent in various subgroups of age and education. The reductions, however, are probably overestimated, since they are based on the women's reports only. Thus, there still appears to be ample scope for intervention on smoking in pregnancy, particularly in older and less educated women.

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Zusammenfassung Die Rauchprävalenz während der Schwangerschaft wurde in einer Querschnittstudie bei Frauen untersucht, welche zwischen Januar und März 1989 in einer grossen Frauenklinik in Mailand ein Kind zur Welt brachten. Von 528 befragten Frauen hatten 183 (35%) vor der Schwangerschaft geraucht, und 99 Frauen war es gelungen, während der Schwangerschaft mit Rauchen aufzuhören. Die Wahrscheinlichkeit für letzteres nahm mit zunehmendem Alter ab und war kleiner für Frauen mit geringer Ausbildung (statistisch nicht signifikant). Bei den Raucherinnen wurde eine Reduktion der mittleren Anzahl Zigaretten von 13 Stück vor der Schwangerschaft auf 8 während der Schwangerschaft festgestellt. Diese Reduktion fand sich in allen Alters- und Ausbildungsgruppen. Wahrscheinlich wurde die Reduktion aber überbewertet, weil sich ihre Berechnung nur auf die Aussagen der Frauen abstützte. Für Gesundheitsaktionen, die ein Rauchstopp während der Schwangerschaft zum Ziele haben, besteht immer noch ein grosser Bedarf, besonders bei älteren und weniger ausgebildeten Frauen.

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Résumé La prévalence du tabagisme durant la grossese a été étudiée lors d'une enquête des parturientes entre janvier et mars 1989 dans une grande maternité de Milan. Parmi les 528 femmes interrogées, 183 (35%) étaient tabagiques avant la grossesse et 99 avaient arrêté de fumer durant la grossesse. La probalité de cesser l'habitude diminue lorsque l'âge augmente, et est basse chez les femmes dont le niveau d'éducation est bas, sans significantion statistique. En considérant uniquement les parturientes tabagiques, le nombre quotidien de cigarettes fumées passe de 13 avant la grossesse à 8 durant la grossesse; cette diminution se retrouve dans tous les groupes d'âge et tous les niveaux d'éducation. Ces diminutions sont probablement surestimées, puisqu'elles sont basées sur les seules déclarations des parturientes. Cette enquête montre qu'il existe encore une large place por la prévention.

     

The validity of infant mortality statistics in Navarra]

In order to explore the validity of official infant mortality statistics, the number of infant deaths registered in the cohort of live births and resident in Navarra (Spain) from 1985 to 1989, according to data supplied by the Department of Statistics of Navarra, has been compared with that obtained in a retrospective search into the information of the hospitals. Among 24,383 live births of the cohort, 291 were certified as infant deaths. An over-register of 13 cases (4.5%) and an under-register of 26 cases (8.9%) was detected. By excluding those live births with less than six months of gestation, as done by the National Institute of Statistics, the validity is altered, because apart from the errors mentioned, one must add those resulting from the incorrect filling-in of the "number of weeks pregnant"= variable. When correcting these deficiencies, the final statistics (Infant Mortality Risk = 11.17 per 1000 live births) did not differ much from the official figures (IMR = 11.48 per 1000 live births).     

Competitive adsorption of magnesium and calcium ions onto synthetic and biological apatites

Summary Magnesium (Mg) is a conspicuous constituent of hard tissues but its possible role in biomineralization is poorly understood. It is possible that Mg²⁺ adsorbed onto bioapatites may contribute to the modulation of crystal growth as such inhibitory activity has been reported for synthetic apatites. The present study was undertaken to determine the adsorption isotherms of Mg ions onto synthetic apatites and biominerals in tooth and bone tissues in the presence of other ions of natural occurrence. Synthetic crystals used as adsorbents were hydroxyapatite and, as a better prototype for the biomineral, Mg-containing carbonatoapatite. Human enamel and dentin materials were obtained from extracted, caries-free, permanent teeth. Porcine dentin materials at two developmental stages were obtained from erupted deciduous and unerupted permanent teeth of a 6-month-old slaughtered piglet. Porcine bone was obtained from the cortical portion of the mandible of the same animal. All biomineral samples were pulverized and then treated by plasma ashing (deproteination) at about 60°C. Each of the powdered samples was equilibrated in solutions containing various initial concentrations of Mg²⁺, Ca²⁺, and Na⁺ (or K⁺) as nitrate salts. Following equilibration, concentrations (and activities) of magnesium and calcium ions in the experimental solution were determined. The pH values of the equilibrium solutions were in the range of 6.2–6.5. Experimental data of the Mg adsorption onto hydroxyapatite were interpreted on the basis of a Langmuir-type model for binary systems assuming competition of Mg²⁺ and Ca²⁺ for the same adsorption sites on the crystal surfaces of the apatites. According to this model, the adsorbed Mg is expressed as a function of the ionic activity ratio (Mg²⁺)/(Ca²⁺) in the equilibrium solution. The model contains two parameters, the adsorption selectivity constant K_s and the maximum number of adsorption sites N (mol/g). The numerical values of K_s were similar for all adsorbents used (synthetic and biological) and indicated the preferential adsorption of Ca²⁺ probably due to spacial restrictions extending to the very surface of the crystals. The initial level of Mg²⁺ in the surface pool was different in the various biominerals, probably reflecting the composition of fluid in which the biominerals were formed. Whereas the surface pool of Mg of human enamel was marginal, only 5% of the total Mg, significant fractions of the total Mg in human and porcine dentins (about 20–30%), and porcine bone (about 40%) existed on the crystal surfaces. There were significant differences in the total Mg and the value of the parameter N between young (unerupted) and mature (erupted) dentin minerals. It was ascertained that the occupancy of adsorption sites by Mg ions became greater with maturation of the dentin tissues. The overall results suggest that the Mg-mineral interaction in tooth and bone tissues may be a highly tissue-specific process, presumably reflecting differences in fluid composition (particularly Ca and Mg activities) responsible for biomineralization.