Management of pediatric ureterolithiasis in the emergency room: A single institution review and new management pathway.

Introduction/background: Urolithiasis is an increasingly common condition seen in children with an annual incidence of 2-3% in children under 18, and up to 10% in adolescents. Treatment of stones varies including observation, IV hydration, pain management, medical expulsive therapy (MET), or surgery. Though well-studied and often used in adults, MET (alpha-adrenergic antagonists to facilitate passage of ureteral stones), is not routinely prescribed in pediatric patients.

Matching the Statistical Model to the Research Question for Dental Caries Indices with Many Zero Counts.

Marginalized zero-inflated count regression models have recently been introduced for the statistical analysis of dental caries indices and other zero-inflated count data as alternatives to traditional zero-inflated and hurdle models. Unlike the standard approaches, the marginalized models directly estimate overall exposure or treatment effects by relating covariates to the marginal mean count. This article discusses model interpretation and model class choice according to the research question being addressed in caries research.

Common risk factor approach to address socioeconomic inequality in the oral health of preschool children--a prospective cohort study.

Background: Dental caries remains the most prevalent chronic condition in children and a major contributor to poor general health. There is ample evidence of a skewed distribution of oral health, with a small proportion of children in the population bearing the majority of the burden of the disease. This minority group is comprised disproportionately of socioeconomically disadvantaged children.

Logistic regression for dichotomized counts.

Sometimes there is interest in a dichotomized outcome indicating whether a count variable is positive or zero. Under this scenario, the application of ordinary logistic regression may result in efficiency loss, which is quantifiable under an assumed model for the counts. In such situations, a shared-parameter hurdle model is investigated for more efficient estimation of regression parameters relating to overall effects of covariates on the dichotomous outcome, while handling count data with many zeroes.

Nonfluoride caries-preventive agents: executive summary of evidence-based clinical recommendations.

Background: In this article, the authors present evidence-based clinical recommendations regarding the use of nonfluoride caries preventive agents. The recommendations were developed by an expert panel convened by the American Dental Association (ADA)Council on Scientific Affairs. The panel addressed several questions regarding the efficacy of nonfluoride agents in reducing the incidence of caries and arresting or reversing the progression of caries.

Effects of binding factors on structural elements in F-actin.

Understanding the dynamics of the actin filament is essential to a detailed description of their interactions and role in the cell. Previous studies have linked the dynamic properties of actin filaments (F-actin) to three structural elements contributing to a hydrophobic pocket, namely, the hydrophobic loop, the DNase I binding loop, and the C-terminus. Here, we examine how these structural elements are influenced by factors that stabilize or destabilize F-actin, using site-directed spin-labeled (SDSL) electron paramagnetic resonance (EPR), fluorescence, and cross-linking techniques.

Hydrophobic loop dynamics and actin filament stability.

It has been postulated that the hydrophobic loop of actin (residues 262-274) swings out and inserts into the opposite strand in the filament, stabilizing the filament structure. Here, we analyzed the hydrophobic loop dynamics utilizing four mutants that have cysteine residues introduced at a single location along the yeast actin loop. Lateral, copper-catalyzed disulfide cross-linking of the mutant cysteine residues to the native C374 in the neighboring strand within the filament was fastest for S265C, followed by V266C, L267C, and then L269C.

Conformational dynamics of loop 262-274 in G- and F-actin.

According to the original Holmes model of F-actin structure, the hydrophobic loop 262-274 stabilizes the actin filament by inserting into a pocket formed at the interface between two protomers on the opposing strand. Using a yeast actin triple mutant, L180C/L269C/C374A [(LC)(2)CA], we showed previously that locking the hydrophobic loop to the G-actin surface by a disulfide bridge prevents filament formation. We report here that the hydrophobic loop is mobile in F- as well as in G-actin, fluctuating between the extended and parked conformations.