Dental questions in Frank Norris's novel "McTeague"

Frank Norris's McTeague, one of the first novels in which the main character is a dentist and dentistry is central to the plot, has been a minor member of the American literary canon for over a century. Possibly because Norris was such a committed and practicing realist/naturalist, his characterization of McTeague as a believable dentist has not until now been questioned. Nor has his use or misuse of the California Dental Licensure Legislation of 1885 to bring about McTeague's downfall been subjected to historical analysis. Such analysis may cast doubt on the credibility and reputation of the novel.     

Adenosine-regulated cell proliferation in pituitary folliculostellate and endocrine cells: differential roles for the A(1) and A(2B) adenosine receptors

A(1) and A(2) adenosine receptors have been identified in the pituitary gland, but the cell type(s) on which they are located and their effects on pituitary cell growth are not known. Therefore, we analyzed the expression of A(1) and A(2) receptors in primary rat anterior pituitary cells, two pituitary folliculostellate (TtT/GF and Tpit/F1) and two pituitary endocrine (GH(3) and AtT20) cell lines, and compared their effects on cell proliferation. In anterior pituitary and folliculostellate cells, adenosine and adenosine receptor agonists (5'-N-ethylcarboxamidoadenosine, a universal agonist, and CGS 21680, an A(2A) receptor agonist) stimulated cAMP levels with a rank order of potency that indicates the presence of functional A(2B) receptors. This stimulation, however, was not observed in either GH(3) or AtT20 cells, where adenosine and the A(1) receptor agonist 2-chloro-N(6)-cyclopentyladenosine inhibited VIP/forskolin-stimulated cAMP production. Expression of A(2B) and A(1) receptors in the folliculostellate cells and that of the A(1) receptor in the endocrine cells were confirmed by RT-PCR, immunocytochemistry, and ligand binding. Adenosine and 5'-N-ethylcarboxamidoadenosine dose-dependently (10 nM to 10 microM) stimulated growth in the folliculostellate, but not in the endocrine, cells, whereas in the latter, 100 microM adenosine and 2-chloro-N(6)-cyclopentyladenosine inhibited cell proliferation by slowing cell cycle progression. These data highlight the differential expression of A(1) and A(2B) adenosine receptors in pituitary cells and provide evidence for opposing effects of adenosine on pituitary folliculostellate and endocrine cell growth.     

Effect of prolonged exercise and carbohydrate on total neutrophil elastase content

PURPOSE: The purpose of the present study was twofold: first, to assess the effect of prolonged intense exercise on total neutrophil elastase content in endurance-trained cyclists and to determine whether this is associated with postexercise falls in lipopolysaccharide (LPS)-stimulated neutrophil elastase release; and second, to determine the effect of carbohydrate (CHO) ingestion during exercise on these responses. METHODS: In a randomized design, nine trained male cyclists cycled for 2 h at 75% VO(2max) on two occasions with either CHO (6.4%, i.e., 64 g x L-1) or placebo (PLA) beverage ingestion before (5 mL x kg-1), during (2 mL x kg-1), and after (5 mL x kg-1) the exercise. Venous blood samples were obtained at rest, immediately postexercise, and at 1 h postexercise. RESULTS: After exercise, CHO ingestion was associated with a higher plasma glucose concentration (P < 0.05) and fewer numbers of circulating neutrophils compared with the PLA trial (P < 0.01). Neither exercise nor CHO ingestion affected total neutrophil elastase content, yet LPS-stimulated neutrophil elastase release fell postexercise by approximately 47% on the PLA trial (P < 0.01). Values did not change significantly from preexercise on the CHO trial. CONCLUSIONS: These findings suggest that neither exercise nor CHO-beverage ingestion influences the total elastase content of neutrophils. Therefore, changes in neutrophil elastase content cannot account for the fall in LPS-stimulated neutrophil elastase release after prolonged intense exercise or for the blunting of this response with CHO ingestion.     

Self-Micellization of Gemfibrozil 1-O-β Acyl Glucuronide in Aqueous Solution

Purpose. Phase II metabolism involves the conjugation of a polar moiety, such as sulfate or glucuronic acid, to a (relatively) nonpolar xenobiotic. Although it might be expected that such conjugates may exhibit amphiphilic character (e.g., surface activity and potential to form micelles), no detailed study of the micellization characteristics of any drug-glucuronide conjugates has yet been reported. Therefore, the aim of this study was to investigate the solution behavior and amphiphilic characteristics of gemfibrozil 1-O- glucuronide (GG), a model drug-glucuronide conjugate. Methods. Crude GG was extracted from the urine of volunteers dosed with 600 mg of gemfibrozil, and this material was then purified by reversed-phase high-performance liquid chromatography to yield a white solid. The amphiphilic properties of GG within the bulk aqueous phase were studied by isothermal titration microcalorimetry and ¹H-NMR spectrometry, whereas those at the aqueous/air interface were studied by surface tensiometry. Results. The results of each independent analytical technique were consistent with GG in aqueous solution exhibiting amphiphilic properties typical of a hydrophilic surfactant. The titration microcalorimetry and ¹H-NMR spectrometry data were in excellent agreement with each other, yielding critical micellization concentrations (cmc) for GG in 0.1 M acetate buffer of 18.1 ± 0.4 mM and 18.3 ± 0.3 mM, respectively. The profile and results of the surface tension measurements were consistent with GG localizing at the aqueous/air interface. Conclusion. These results confirm the hypothesis that a glucuronide conjugate of a relatively nonpolar xenobiotic, such as gemfibrozil, behaves as an amphiphile in aqueous solution. The implications of this observation include a likely basis for the previously observed concentration-dependence in the degradation rate of the acyl glucuronides of 2-phenylpropionic acid, as well as identifying a possible broader contributory effect to the structural dependencies in biliary choleresis of different glucuronide conjugates of xenobiotics.     

Does overweight in infancy persist through the preschool years? An analysis of CDC Pediatric Nutrition Surveillance System data

SummaryObjective: To determine whether overweight in infancy (0-11 months) and young childhood (12-35 months) persists through the preschool years.Methods: Analysis of longitudinal surveillance data for 380 518 low-income children monitored in the U.S. Pediatric Nutrition Surveillance System from birth to age 59 months. Overweight was defined as weight-for-height 95th percentile. We determined the proportion of the children (overweight vs non-overweight) above or below the 95th percentile of weight-forheight at the later ages.Results: The relative risk (RR) for overweight among overweight infants (vs non-overweight infants) at 1, 2, 3, and 4 years old was 4.3, 3.5, 3.3, and 2.9, respectively. 62.5% of overweight 3-year-old was still overweight a year later, but only 4.1% non-overweight 3-year-old became overweight a year later (RR = 15.2). However, low birth weight children had the highest RR to remain overweight after they became overweight compared to normal and high birth weight children.Conclusions: Overweight during infancy persists through the preschool years. Tracking of overweight appears to become stronger as children get older and is more pronounced among low birth weight children than normal or high birth weight children. Monitoring preschoolers' height and weight status should be a strategy for preventing of obesity in adolescence and adulthood.

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Zusammenfassung Bleibt das Übergewicht von Kleinkindern während der Vorschulzeit bestehen? Eine Analyse von Daten des CDC-Kinderernährungs-Surveillance-SystemsZielsetzung: Bestimmen, ob das Übergewicht im Säuglings und Kleinkindalter (0-11 resp. 12-35 Monate) während der Vorschulzeit bestehen bleibt.Methoden: Analyse von Langsschnitt-Surveillance-Daten für 380 518 Kinder aus Familien mit niedrigem Einkommen, die im Rahmen des U.S.-Kinderernährungs-Surveillance-Systems von der Geburt bis im Alter von 59 Monaten beobachtet werden. Übergewicht wurde definiert als 95. Gewichts-Grössen-Perzentil. Wir bestimmten den Anteil an älteren Kindern über oder unter der 95. Gewichts-Grössen-Perzentile (übergewichtig vs. nicht übergewichtig).Ergebnisse: Das relative Risiko (RR) für Übergewicht unter den übergewichtigen Kleinkindern (im Vergleich zu den nicht übergewichtigen) betrug im Alter von 1, 2, 3 und 4 Jahren 4,3; 3,5; 3,3 und 2,9. 62,5% der übergewichtigen 3-jährigen Kinder war auch ein Jahr später noch übergewichtig, aber nur 4,1% der nicht übergewichtigen 3-Jährigen wurden im selben Zeitraum übergewichtig (RR = 15,2). Kinder mit sehr geringem Geburtsgewicht hatten im Vergleich zu Kindern mit normalem oder hohem Geburtsgewicht das höchste RR übergewichtig zu bleiben nachdem sie einmal übergewichtig geworden waren.Schlussfolgerungen: Übergewicht im Kleinkindalter bleibt während der Vorschuljahre bestehen. Mit zunehmendem Alter der Kinder scheint dieses Problem noch extremer zu werden und ist bei Kindern mit niedrigem Geburtsgewicht besonders ausgeprägt. Ein Monitoring von Körpergewicht und -grösse bei Vorschulkindern sollte als Strategie zur Vorbeugung von Adipositas bei Jugendlichen und Erwachsenen berücksichtigt werden.

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Résumé Est-ce que le surpoids dans l'enfance persiste jusqu'aux années préscholaires? Une analyse des données du CDC Pediatric Nutrition Surveillance SystemObjectif: Déterminer si le supoids pendant la très petite enfance (0 à 11 mois) et la petite enfance (12 à 35 mois) persiste jusqu'aux années préscolaires.Méthodes: Analyses de données d'observation longitudinale portant sur 380 518 enfants de bas niveau socio-économique suivis par le système de surveillance de nutrition pédiatrique des Etats-Unis de la naissance jusqu'à l'âge de 59 mois. Le surpoids était défini comme un rapport poids/taille 95ème percentile. Nous avons déterminé la proportion d'enfants (avec vs. sans surpoids) au-dessous et au-dessus du 95ème percentile du rapport poids/taille à des ages plus avancés.Résultats: Le risque relatif (RR) du surpoids (comparé à l'absence de surpoids) à 1,2,3 et 4 ans était de 4,3, 3,5, 3,3 et 2,9, respectivement. 62,5% des enfants de 3 ans ayant du surpoids en avaient toujours un an plus tard, mais seulement 4,1% des enfants de 3 ans sans surpoids développaient du surpoids un an plus tard (RR = 15,2). Cependant, les enfants de bas poids à la naissance avaient le plus grand risque relatif de conserver du surpoids après qu'ils en aient développé comparés aux enfants de poids normal ou élevé à la naissance.Conclusions: Le surpoids pendant la petite et très petite enfance persiste jusqu'aux années préscolaire. La tendance au surpoids semble devenir plus forte lorsque les enfants grandissent et est plus prononcée chez les enfants de bas poids à la naissance que chez ceux de poids normal ou élevé à la naissance. L'observation continue de la taille et du poids des enfants en age préscolaire devrait être une stratégie de prêvention de l'obésité au cours de l'adolescence et de l'age adulte.

     

Pneumocystis carinii pneumonia alters expression and distribution of lung collectins SP-A and SP-D

Surfactant proteins SP-A and SP-D, members of the collectin family, have been shown to play a significant role in lung host defense. Both proteins selectively bind Pneumocystis carinii (PC) organisms and modulate the interaction of this pathogen with alveolar macrophages. We hypothesized that the expression and distribution of lung collectins SP-A and SP-D is altered by PC lung infection. PC organisms (2 x 10(5)) were inoculated intratracheally into C.B-17 scid/scid mice that do not require steroids for immunosuppression. Four weeks after inoculation, bronchoalveolar lavage (BAL) fluid was fractionated into three fractions-cell pellet, large aggregate (LA), and small aggregate (SA) surfactant-and each fraction was analyzed for the expression of surfactant components. In uninfected mice, the majority of SP-A (62% +/- 10%) was found in association with lipids in the LA fraction, while 55% +/- 14% of SP-D was distributed in the SA fraction. In contrast, both hydrophobic proteins SP-B and SP-C were associated exclusively with LA. PC infection resulted in major changes in the expression of all surfactant components. Total protein content of LA was unchanged by PC infection (115% +/- 18% of control), whereas SA protein content markedly increased (240% +/- 18% of control level, P <.001). In contrast, the phospholipid content of LA was significantly decreased (53% +/- 5% of control level, P <.001), whereas the SA phospholipid content of infected mice was increased (172% +/- 16% of control level, P <.001). By Western blotting, PC pneumonia (PCP) induced a 3-fold increase in the total alveolar SP-D protein that was reflected mainly in increases in SA SP-D (454% +/- 135% of control, P <.05). The total alveolar SP-A protein content was also increased in PCP because of a large increase in SP-A in SA (720% +/- 115% of control, P <.05); SP-A levels in LA were unchanged. The increases in lung collectin expression were selective, because PCP resulted in the down-regulation of both SP-B and SP-C in LA (5% +/- 2% and 13% +/- 2% of control, respectively, P <.001). We conclude that PCP induces marked elevations in alveolar collectin levels because of increased expression and accumulation of SP-A and SP-D protein in SA surfactant.     

Vitamin A and cardiac outflow tract defects

To assess the relationship between maternal intake of vitamin A and cardiac outflow tract defects, we examined data from a population-based case-control study among liveborn infants born from 1987 through 1989 to mothers residing in the Baltimore-Washington area. Case infants (126) had a nonsyndromic cardiac outflow tract defect. Control infants (679) did not have birth defects and were a stratified random sample of liveborn infants from the same area. The main exposure was average daily maternal intake of retinol and provitamin A carotenoids from foods and supplements during the year before conception. Compared with an average intake of less than 10,000 IU, retinol intake of 10,000 IU or more from supplements was associated with a ninefold increased risk for transposition of the great arteries (odds ratio = 9.2; 95% confidence interval = 4.0-21.2), but not for outflow tract defects with normally related arteries (odds ratio = 0.8; 95% confidence interval = 0.1-6.6). Similar intakes of carotenoids and dietary retinol were not associated with an increased risk for either type of outflow tract defect.     

Prepregnancy body mass index and pregnancy weight gain: associations with preterm delivery. The NMIHS Collaborative Study Group

OBJECTIVE: To examine associations between rate of pregnancy weight gain and preterm delivery among women of varying prepregnancy body mass indices (BMI). METHODS: Subjects were 3511 mother-infant pairs from the 1988 National Maternal and Infant Health Survey. Prenatal weight measured between 14 and 28 weeks' gestation was used to calculate rate of pregnancy weight gain for each woman. Weight gain (lb/week) was categorized as low (under 0.5), average (0.5-1.5), or high (above 1.5). Prepregnancy BMI was calculated as weight divided by height in (kg/m(2)) and categorized as low (under 19.8), average (19.8-26.0), and high (above 26). Delivery before 37 weeks' gestation was considered preterm. Associations between BMI, weight gain, and preterm delivery were examined before and after exclusion of medically indicated preterm deliveries and pregnancies complicated by maternal medical conditions potentially related to weight gain or fetal growth restriction. Associations were expressed as odds ratios (OR) adjusted for several potential confounding factors. RESULTS: Women with low pregnancy weight gain were at increased risk of preterm delivery. The magnitude of risk varied according to a woman's prepregnancy BMI. After all exclusions and adjustments for confounders, ORs, and 95% confidence intervals (CI) for low pregnancy weight gain were 6.7 (1.1, 40.6) for underweight women, 3.6 (1.6, 8.0) for average-weight women, and 1.6 (0.7, 3.5) for overweight women compared with average-weight women with average pregnancy weight gain. CONCLUSIONS: Low weight gain in pregnancy was associated with increased risk of preterm delivery, particularly if women were underweight or of average weight before pregnancy.     

The effects of theophylline on renal function in the premature newborn.

The effects of aminophylline on renal function in 10 premature infants with idiopathic apnea are evaluated. The percent increases in creatinine clearance (128 +/- 339%, mean +/- SD) and sodium clearance (196 +/- 304%, mean +/- SD) are variable while the percent increase in fractional sodium excretion (69 +/- 109%, mean +/- SD) is significant. This effect is postulated to be at the proximal tubule and may be modified by the effects of postnatal age and infusion of albumin. Gestational age, birth weight, heart disease, water and sodium intake and ventilatory support did not appear to influence the results. Hyponatremia is a potential consequence of theophylline therapy for apnea.