bluuebunny/crossref_metadata_2025_split huggingface dataset:
Substratum cavities affect growth-plasticity, allometry, movement and feeding rates in the sea urchinStrongylocentrotus purpuratus
Authors: Hernández J. C. , Russell M. P. 
Published: January 2010

SUMMARYWe assessed the influence of rock cavities, or pits, on the growth dynamics and behavior of the purple sea urchin, Strongylocentrotus purpuratus. In a paired-designed, laboratory experiment, sea urchins were assigned to sandstone blocks that were either ‘Flat’ or had a ‘Pit’ drilled into the center. At the start, both groups were approximately the same shape and size. In just 2 months, the shapes of the tests were significantly different between the two treatments, with the Pit urchins having an increased height:diameter profile. This result demonstrates the plastic nature of the sea urchin test and that, despite its apparent rigidity, it is capable of deforming during growth. In addition, the presence of pits modified behavior and food consumption as well as allometric growth of the test and Aristotle's lantern. Sea urchins on Pit sandstone blocks tended to stay in the cavities and not move about the flat areas, whereas individuals on Flat blocks changed position. Sea urchins in the Pit treatment consumed less food and had relatively larger demipyramids (the ‘jaw’ ossicle in Aristotle's lantern). These morphological and allometric changes occurred over a short time-period (8–20 weeks). We conclude that microhabitat is an important factor in controlling the behavior and growth dynamics of the bioeroding sea urchin S. purpuratus.
Approaching the evolutionary advantage of ancillary types of haemoglobin in Daphnia magna by simulation of oxygen supply
Authors: Moenickes S. , Richter O. , Pirow R. 
Published: January 2010

SUMMARY
The planktonic crustacean Daphnia magna synthesizes haemoglobin (Hb) macromolecules of variant subunit composition and oxygen affinity. This is one of the strategies by which the animals cope with variations in environmental conditions such as ambient oxygen tension. The enrichment of high-affinity Hb molecules in the haemolymph of hypoxia-exposed animals is thought to reduce Hb synthesis costs due to an enhanced transport efficiency of these molecules in comparison to the low-affinity Hb molecules. How great this economic advantage is, and under which conditions this benefit disappears, is still not fully understood. Here we implemented a rigorously simplified model of the daphnid body and described the transport of oxygen from the environment via the haemolymph to the tissues in terms of the convection–diffusion–reaction equation. The model was validated by comparing various model predictions with experimental data. A sensitivity analysis was used to evaluate the influence of parameter uncertainties on the model predictions. Cost–benefit analysis revealed in which way at the system's level the increase in Hb oxygen affinity improves the oxygen loading at the respiratory surfaces and impairs the release of oxygen to the tissues. The benefit arising from the improved oxygen loading exceeds the disadvantage of impaired unloading only under conditions where the ambient oxygen tension is critically low and the Hb concentration is high. The low-affinity Hb, on the other hand, provides an advantage given that the Hb concentration is low and the ambient oxygen tension is well above the critical level. Computer-aided modelling and simulation therefore provide valuable mechanistic insights into the driving forces that could have shaped the evolution of globin genes in daphnids.
Characterization of ion transport in the isolated epipodite of the lobsterHomarus americanus
Authors: Lucu Č. , Towle D. W. 
Published: January 2010

SUMMARYUnfolded epipodite isolated from American lobsters (Homarus americanus) acclimated to dilute seawater was mounted in an Ussing-type chamber for ion transport studies. The split epipodite is an electrically polarized, one-cell-layer epithelium supported with cuticle. Under open-circuit conditions, the transepithelial potential was –4.2±1.0 mV (N=38). In the short-circuited epithelium, the current averaged over all of the preparations was –185.4±20.2 A cm–2 (N=38) with a high conductance of 55.2±11.4 mS cm–2 (N=38), typical for a leaky epithelium. The Na:Cl absorptive flux ratio was 1:1.6; ion substitution experiments indicated that the transport of Na+ and Cl– is coupled. Basolateral application of the Cl– channel blockers 5-nitro-2-(3-phenylpropylamino) benzoate (NPPB) and niflumic acid (NFA) dose-dependently inhibited short-circuit current (ISC). Secretory K+ (Rb+) fluxes exceeded influxes and were inhibited by the Na+/K+-ATPase inhibitor ouabain and the K+ channel blocker cesium. Western blot analysis showed that Na+/K+-ATPase α-subunit protein was more highly expressed in the epipodite of lobsters acclimated to 20 p.p.t. compared with animals acclimated to seawater (34 p.p.t.). 3-Isobutyl-1-methyl-xanthine (IBMX) stimulated a negative ISC and enhanced apical secretory K+ flux. Basolateral application of NPPB inhibited JRbB→A fluxes, suggesting the interaction of K+ channels with NPPB-sensitive Cl– channels. The results are summarized in a transport model, suggesting apical Na+/K+/2Cl– co-transport, a dominant apical K+-secreting channel and basolaterally located Cl– and K+ channels. This study represents the first comprehensive characterization of ion transport processes across the lobster epipodite epithelium and indeed in any tissue within the branchial cavity of the American lobster.
Aquaporin expression dynamics in osmoregulatory tissues of Atlantic salmon during smoltification and seawater acclimation
Authors: Tipsmark C. K. , Sørensen K. J. , Madsen S. S. 
Published: January 2010

SUMMARY
Osmotic balance in fish is maintained through the coordinated regulation of water and ion transport performed by epithelia in intestine, kidney and gill. In the current study, six aquaporin (AQP) isoforms found in Atlantic salmon (Salmo salar) were classified and their tissue specificity and mRNA expression in response to a hyperosmotic challenge and during smoltification were examined. While AQP-1a was generic, AQP-1b had highest expression in kidney and AQP-3 was predominantly found in oesophagus, gill and muscle. Two novel teleost isoforms, AQP-8a and -8b, were expressed specifically in liver and intestinal segments, respectively. AQP-10 was predominantly expressed in intestinal segments, albeit at very low levels. Transfer from freshwater (FW) to seawater (SW) induced elevated levels of intestinal AQP-1a, -1b and -8b mRNA, whereas only AQP-8b was stimulated during smoltification. In kidney, AQP-1a, -3 and -10 were elevated in SW whereas AQP-1b was reduced compared with FW levels. Correspondingly, renal AQP-1a and -10 peaked during smoltification in April and March, respectively, as AQP-1b and AQP-3 declined. In the gill, AQP-1a and AQP-3 declined in SW whereas AQP-1b increased. Gill AQP-1a and -b peaked in April, whereas AQP-3 declined through smoltification. These reciprocal isoform shifts in renal and gill tissues may be functionally linked with the changed role of these organs in FW compared with SW. The presence and observed dynamics of the AQP-8b isoform specifically in intestinal sections suggest that this is a key water channel responsible for water uptake in the intestinal tract of seawater salmonids.
Deep supercooling, vitrification and limited survival to –100°C in the Alaskan beetleCucujus clavipes puniceus(Coleoptera: Cucujidae) larvae
Authors: Sformo T. , Walters K. , Jeannet K. , Wowk B. , Fahy G. M. , Barnes B. M. , Duman J. G. 
Published: January 2010

SUMMARYLarvae of the freeze-avoiding beetle Cucujus clavipes puniceus (Coleoptera: Cucujidae) in Alaska have mean supercooling points in winter of –35 to –42°C, with the lowest supercooling point recorded for an individual of –58°C. We previously noted that some larvae did not freeze when cooled to –80°C, and we speculated that these larvae vitrified. Here we present evidence through differential scanning calorimetry that C. c. puniceus larvae transition into a glass-like state at temperatures &lt;–58°C and can avoid freezing to at least –150°C. This novel finding adds vitrification to the list of insect overwintering strategies. While overwintering beneath the bark of fallen trees, C. c. puniceus larvae may experience low ambient temperatures of around –40°C (and lower) when microhabitat is un-insulated because of low snow cover. Decreasing temperatures in winter are correlated with loss of body water from summer high levels near 2.0 to winter lows near 0.4 mg mg–1 dry mass and concomitant increases in glycerol concentrations (4–6 mol l–1) and thermal hysteresis. Finally, we provide direct evidence that Cucujus from Wiseman, Alaska, survive temperatures to –100°C.
Effects of cadmium exposure and intermittent anoxia on nitric oxide metabolism in eastern oysters,Crassostrea virginica
Authors: Ivanina A. V. , Eilers S. , Kurochkin I. O. , Chung J. S. , Techa S. , Piontkivska H. , Sokolov E. P. , Sokolova I. M. 
Published: January 2010

SUMMARYNitric oxide (NO) is an intracellular signaling molecule synthesized by a group of enzymes called nitric oxide synthases (NOS) and involved in regulation of many cellular functions including mitochondrial metabolism and bioenergetics. In invertebrates, the involvement of NO in bioenergetics and metabolic responses to environmental stress is poorly understood. We determined sensitivity of mitochondrial and cellular respiration to NO and the effects of cadmium (Cd) and intermittent anoxia on NO metabolism in eastern oysters, Crassostrea virginica. NOS activity was strongly suppressed by exposure to 50 μg l–1 Cd for 30 days (4.76 vs 1.19 pmol NO min–1 mg–1 protein in control and Cd-exposed oysters, respectively) and further decreased during anoxic exposure in Cd-exposed oysters but not in their control counterparts. Nitrate/nitrite content (indicative of NO levels) decreased during anoxic exposure to less than 10% of the normoxic values and recovered within 1 h of re-oxygenation in control oysters. In Cd-exposed oysters, the recovery of the normoxic NO levels lagged behind, reflecting their lower NOS activity. Oyster mitochondrial respiration was inhibited by exogenous NO, with sensitivity on a par with that of mammalian mitochondria, and ADP-stimulated mitochondrial respiration was significantly more sensitive to NO than resting respiration. In isolated gill cells, manipulations of endogenous NOS activity either with a specific NOS inhibitor (aminoguanidine) or a NOS substrate (l-arginine) had no effect on respiration, likely due to the fact that mitochondria in the resting state are relatively NO insensitive. Likewise, Cd-induced stimulation of cellular respiration did not correlate with decreased NOS activity in isolated gill cells. High sensitivity of phosphorylating (ADP-stimulated) oyster mitochondria to NO suggests that regulation of bioenergetics is an evolutionarily conserved function of NO and that NO-dependent regulation of metabolism may be most prominent under the conditions of high metabolic flux when the ADP-to-ATP ratio is high.
Male sex, single nodularity, and young age are associated with the risk of finding a papillary thyroid cancer on fine-needle aspiration cytology in a large series of patients with nodular thyroid disease
Authors: Rago T , Fiore E , Scutari M , Santini F , Di Coscio G , Romani R , Piaggi P , Ugolini C , Basolo F , Miccoli P , Pinchera A , Vitti P 
Published: January 2010

ObjectiveTo evaluate the risk of papillary thyroid carcinoma (PTC) at fine-needle aspiration (FNA) cytology in 34 120 patients.ResultsFalse positive and false negative rates of FNA cytology were 1.2 and 1.8% in comparison with the histology in 3406 nodules from 3004 patients who underwent surgery. PTC (901 cases) was more frequent in solitary nodule (SN; 446/13 549, 3.3%) than in multinodular goiter (MNG; 411/19 923, 2%,χ2=48.8;P<0.0001), and in males (209/6382, 3.3%) than in females (648/26 945, 2.40%,χ2=15.58;P<0.0001). PTC prevalence in Graves' disease (GD; 13/286, 4.5%) and Hashimoto's thyroiditis (HT; 31/508, 6.1%) was higher than in SN, this difference being significant in HT (χ2=8.7;P=0.003), but not in GD (χ2=1.6;P=0.2).Using the multiple logistic regression analysis, independent risk predictors of PTC were determined, which were younger age (odds ratio (OR)=0.97, confidence interval (CI) 0.964–0.974;P<0.0001), male gender (OR=1.44, CI 1.231–1.683;P<0.0001), and SN versus MNG (OR=0.63, CI 0.547–0.717;P<0.0001). The individual risk predictivity was highly improved by including serum TSH in the prediction model, which was measured at FNA in 11 919 patients.ConclusionA cytology suspicious or indicative of PTC was associated with younger age, male gender, and solitary versus multiple nodularity. These clinical parameters, together with serum TSH, may allow formulation of an algorithm that could be usefully applied to predict the risk of PTC in individual patients when cytology does not give a diagnostic result.
Adoption of Body Mass Index Guidelines for Screening and Counseling In Pediatric Practice
Authors: Klein Jonathan D. , Sesselberg Tracy S. , Johnson Mark S. , O'Connor Karen G. , Cook Stephen , Coon Marian , Homer Charles , Krebs Nancy , Washington Reginald 
Published: January 2010

OBJECTIVE:
The purpose of this study was to examine pediatrician implementation of BMI and provider interventions for childhood overweight prevention and treatment.

METHODS:
Data were obtained from the American Academy of Pediatrics (AAP) Periodic Survey of Fellows No. 65, a nationally representative survey of AAP members. Surveys that addressed the provision of screening and management of childhood overweight and obesity in primary care settings were mailed to 1622 nonretired US AAP members in 2006.

RESULTS:
One thousand five (62%) surveys were returned; 677 primary care clinicians in active practice were eligible for the survey. Nearly all respondents (99%) reported measuring height and weight at well visits, and 97% visually assess children for overweight at most or every well-child visit. Half of the respondents (52%) assess BMI percentile for children older than 2 years. Most pediatricians reported that they do not have time to counsel on overweight and obesity, that counseling has poor results, and that having simple diet and exercise recommendations would be helpful in their practice. Pediatricians in large practices and those who had attended continuing medical education on obesity were more familiar with national expert guidelines, were more likely to use BMI percentile, and had higher self-efficacy in practices related to childhood and adolescent overweight and obesity. Multivariate analysis revealed that pediatricians with better access to community and adjunct resources were more likely to use BMI percentile.

CONCLUSIONS:
BMI-percentile screening in primary pediatric practice is underused. Most pediatricians believe that they can and should try to prevent overweight and obesity, yet few believe there are good treatments once a child is obese. Training, time, and resource limitations affect BMI-percentile use. Awareness of national guidelines may improve rates of BMI-percentile use and recognition of opportunities to prevent childhood and adolescent obesity.
Male Gender Is Associated With Intraventricular Hemorrhage
Authors: Mohamed Mohamed A. , Aly Hany 
Published: January 2010

OBJECTIVE:The goal was to examine the association of gender with intraventricular hemorrhage (IVH) or periventricular leukomalacia (PVL) in a large national database.METHODS:The National Inpatient Sample database was analyzed for the years 1998, 1999, 2001, 2002, and 2004 and its pediatrics version for the years 1997, 2000, and 2003. The National Inpatient Sample and its pediatrics version are annually collected databases for inpatient admissions from &gt;1000 hospitals across the United States. We included all very low birth weight (VLBW) infants (birth weight [BW] of &lt;1500 g) and excluded infants with major congenital anomalies. VLBW infants with IVH or PVL were identified by using International Classification of Diseases, Ninth Revision, diagnostic codes. We analyzed the data by using χ2 and Fisher's exact tests to calculate odds ratios (ORs) and logistic regression analysis to control for possible confounders.RESULTS:The data included 104 847 VLBW infants. With controlling for significant confounders, IVH was associated with male gender (15.9% vs 13.6%; adjusted OR [AOR]: 1.15 [95% confidence interval: 1.11–1.19]; P &lt; .001). More boys than girls had severe IVH (38% vs 32.7%; AOR: 1.18 [95% confidence interval: 1.06–1.32]; P &lt; .004). The increased rates of IVH and severe IVH in boys were significant in the BW subgroups of &lt;1000 g and 1000 to 1499 g. The association of male gender with IVH and severe IVH was more significant in infants of 1000 to 1499 g (AOR: 1.19 vs 1.14; P = .006). The incidence of PVL in VLBW infants was 0.41%, and rates did not differ between genders (0.38% vs 0.43%; P = .42).CONCLUSIONS:Compared with girls, VLBW male newborns are at greater risk to develop IVH and severe IVH but not PVL. The association of male gender with IVH or severe IVH is stronger with higher BWs.
Health-Related Quality of Life of Children With Mild to Moderate Chronic Kidney Disease
Authors: Gerson Arlene C. , Wentz Alicia , Abraham Allison G. , Mendley Susan R. , Hooper Stephen R. , Butler Robert W. , Gipson Debbie S. , Lande Marc B. , Shinnar Shlomo , Moxey-Mims Marva M. , Warady Bradley A. , Furth Susan L. 
Published: January 2010

OBJECTIVE:To compare the health-related quality of life (HRQoL) of children with chronic kidney disease (CKD) with healthy children; to evaluate the association between CKD severity and HRQoL; and to identity demographic, socioeconomic, and health-status variables that are associated with impairment in HRQoL in children with mild to moderate CKD.METHODS:This was a cross-sectional assessment of HRQoL in children who were aged 2 to 16 and had mild to moderate CKD using the Pediatric Inventory of Quality of Life Core Scales (PedsQL). Overall HRQoL and PedsQL domain means for parents and youth were compared with previously published norms by using independent sample t tests. Study participants were categorized by kidney disease stage (measured by iohexol-based glomerular filtration rate [iGFR]), and group differences in HRQoL were evaluated by using analysis of variance and Cuzick trend tests. The association between hypothesized predictors of HRQoL and PedsQL scores was evaluated with linear and logistic regression analyses.RESULTS:The study sample comprised 402 participants (mean age: 11 years, 60% male, 70% white, median iGFR: 42.5 mL/min per 1.73 m2, median CKD duration: 7 years). Youth with CKD had significantly lower physical, school, emotional, and social domain scores than healthy youth. iGFR was not associated with HRQoL. Longer disease duration and older age were associated with higher PedsQL scores in the domains of physical, emotional, and social functioning. Older age was associated with lower school domain scores. Maternal education ≥16 years was associated with higher PedsQL scores in the domains of physical, school, and social functioning. Short stature was associated with lower scores in the physical functioning domain.CONCLUSIONS:Children with mild to moderate CKD, in comparison with healthy children, reported poorer overall HRQoL and poorer physical, school, emotional, and social functioning. Early intervention to improve linear growth and to address school functioning difficulties is recommended.
Cerebral Magnetic Resonance Biomarkers in Neonatal Encephalopathy: A Meta-analysis
Authors: Thayyil Sudhin , Chandrasekaran Manigandan , Taylor Andrew , Bainbridge Alan , Cady Ernest B. , Chong W. K. Kling , Murad Shahed , Omar Rumana Z. , Robertson Nicola J. 
Published: January 2010

OBJECTIVE:Accurate prediction of neurodevelopmental outcome in neonatal encephalopathy (NE) is important for clinical management and to evaluate neuroprotective therapies. We undertook a meta-analysis of the prognostic accuracy of cerebral magnetic resonance (MR) biomarkers in infants with neonatal encephalopathy.METHODS:We reviewed all studies that compared an MR biomarker performed during the neonatal period with neurodevelopmental outcome at ≥1 year. We followed standard methods recommended by the Cochrane Diagnostic Accuracy Method group and used a random-effects model for meta-analysis. Summary receiver operating characteristic curves and forest plots of each MR biomarker were calculated. χ2 tests examined heterogeneity.RESULTS:Thirty-two studies (860 infants with NE) were included in the meta-analysis. For predicting adverse outcome, conventional MRI during the neonatal period (days 1–30) had a pooled sensitivity of 91% (95% confidence interval [CI]: 87%–94%) and specificity of 51% (95% CI: 45%–58%). Late MRI (days 8–30) had higher sensitivity but lower specificity than early MRI (days 1–7). Proton MR spectroscopy deep gray matter lactate/N-acetyl aspartate (Lac/NAA) peak-area ratio (days 1–30) had 82% overall pooled sensitivity (95% CI: 74%–89%) and 95% specificity (95% CI: 88%–99%). On common study analysis, Lac/NAA had better diagnostic accuracy than conventional MRI performed at any time during neonatal period. The discriminatory powers of the posterior limb of internal capsule sign and brain-water apparent diffusion coefficient were poor.CONCLUSIONS:Deep gray matter Lac/NAA is the most accurate quantitative MR biomarker within the neonatal period for prediction of neurodevelopmental outcome after NE. Lac/NAA may be useful in early clinical management decisions and counseling parents and as a surrogate end point in clinical trials that evaluate novel neuroprotective therapies.
Clinical Performance of Vital Bleaching Techniques
Authors: Bernardon J. K. , Sartori N. , Ballarin A. , Perdigão J. , Lopes G. , Baratieri L. N. 
Published: January 2010

Clinical Relevance
Tooth bleaching results obtained with different techniques (home bleaching, in-office bleaching with or without light source and a combination of in-office bleaching + home bleaching) were similar after a two-week period. Dentists must inform their patients about the expected outcomes of each procedure and provide an evidence-based choice.
Evaluation of Proximal Contact Tightness of Class II Resin Composite Restorations
Authors: Saber M. H. , Loomans A. C. , Zohairy A. El , Dörfer C. E. , El-Badrawy W. 
Published: January 2010

Clinical RelevanceThe use of sectional matrix bands combined with a separation ring and wedge is recommended to reconstruct the proximal contact area of Class II resin composite restorations
Influence of Adhesive Application Time on Enamel Bond Strength of Single-step Self-etch Adhesive Systems
Authors: Tsuchiya H. , Tsubota K. , Iwasa M. , Ando S. , Miyazaki M. , Platt J. A. 
Published: January 2010

Clinical Relevance
Proper application duration of single-step self-etch adhesive plays an important role in obtaining optimal enamel bond strength.