40 research outputs found
Festschrift Symposium: Honoring Professor Samuel Pillsbury
The Loyola of Los Angeles Law Review is pleased to publish this Festschrift Symposium Honoring Professor Samuel Pillsbury. The following is an edited transcript of the live symposium held at LMU Loyola Law School on Friday, March 25, 2022
Program Innovations and Character in Cub Scouts: Findings from Year 1 of a Mixed-Methods, Longitudinal Study
Youth development programs seek to promote positive development through mentoring and engaging youth in opportunities for individual growth and community connectedness. We present findings from the initial phase of a mixed-methods, longitudinal study aimed at assessing the impact of one such program, Cub Scouts, on character development. We assessed if Scouting, and a recent innovation in Scouting focused on program quality, are associated with the development of character and other positive youth outcomes. Participants were 1,083 Scouts and non-Scouts, aged 5-12 years. At the start of the study, there was no difference in indicators of character between Scouts and non-Scouts, once matched through propensity score analyses. Through content analyses of interviews and short- answer questionnaires administered to leaders, we found that leaders’ views of character and of their roles corresponded to those envisioned by Cub Scouts. Implications for character development, and for the role of program components in character development, are discussed
Time-Lapse Analysis and Mathematical Characterization Elucidate Novel Mechanisms Underlying Muscle Morphogenesis
Skeletal muscle morphogenesis transforms short muscle precursor cells into long, multinucleate myotubes that anchor to tendons via the myotendinous junction (MTJ). In vertebrates, a great deal is known about muscle specification as well as how somitic cells, as a cohort, generate the early myotome. However, the cellular mechanisms that generate long muscle fibers from short cells and the molecular factors that limit elongation are unknown. We show that zebrafish fast muscle fiber morphogenesis consists of three discrete phases: short precursor cells, intercalation/elongation, and boundary capture/myotube formation. In the first phase, cells exhibit randomly directed protrusive activity. The second phase, intercalation/elongation, proceeds via a two-step process: protrusion extension and filling. This repetition of protrusion extension and filling continues until both the anterior and posterior ends of the muscle fiber reach the MTJ. Finally, both ends of the muscle fiber anchor to the MTJ (boundary capture) and undergo further morphogenetic changes as they adopt the stereotypical, cylindrical shape of myotubes. We find that the basement membrane protein laminin is required for efficient elongation, proper fiber orientation, and boundary capture. These early muscle defects in the absence of either lamininβ1 or lamininγ1 contrast with later dystrophic phenotypes in lamininα2 mutant embryos, indicating discrete roles for different laminin chains during early muscle development. Surprisingly, genetic mosaic analysis suggests that boundary capture is a cell-autonomous phenomenon. Taken together, our results define three phases of muscle fiber morphogenesis and show that the critical second phase of elongation proceeds by a repetitive process of protrusion extension and protrusion filling. Furthermore, we show that laminin is a novel and critical molecular cue mediating fiber orientation and limiting muscle cell length
In search of quality evidence for lifestyle management and glycemic control in children and adolescents with type 2 diabetes: A systematic review
<p>Abstract</p> <p>Background</p> <p>Our purpose was to evaluate the impact of lifestyle behavior modification on glycemic control among children and youth with clinically defined Type 2 Diabetes (T2D).</p> <p>Methods</p> <p>We conducted a systematic review of studies (randomized trials, quasi-experimental studies) evaluating lifestyle (diet and/or physical activity) modification and glycemic control (HbA1c). Our data sources included bibliographic databases (EMBASE, CINAHL<sup>®</sup>, Cochrane Library, Medline<sup>®</sup>, PASCAL, PsycINFO<sup>®</sup>, and Sociological Abstracts), manual reference search, and contact with study authors. Two reviewers independently selected studies that included any intervention targeting diet and/or physical activity alone or in combination as a means to reduce HbA1c in children and youth under the age of 18 with T2D.</p> <p>Results</p> <p>Our search strategy generated 4,572 citations. The majority of citations were not relevant to the study objective. One study met inclusion criteria. In this retrospective study, morbidly obese youth with T2D were treated with a very low carbohydrate diet. This single study received a quality index score of < 11, indicating poor study quality and thus limiting confidence in the study's conclusions.</p> <p>Conclusions</p> <p>There is no high quality evidence to suggest lifestyle modification improves either short- or long-term glycemic control in children and youth with T2D. Additional research is clearly warranted to define optimal lifestyle behaviour strategies for young people with T2D.</p
Mutations in Zebrafish lrp2 Result in Adult-Onset Ocular Pathogenesis That Models Myopia and Other Risk Factors for Glaucoma
The glaucomas comprise a genetically complex group of retinal neuropathies that typically occur late in life and are characterized by progressive pathology of the optic nerve head and degeneration of retinal ganglion cells. In addition to age and family history, other significant risk factors for glaucoma include elevated intraocular pressure (IOP) and myopia. The complexity of glaucoma has made it difficult to model in animals, but also challenging to identify responsible genes. We have used zebrafish to identify a genetically complex, recessive mutant that shows risk factors for glaucoma including adult onset severe myopia, elevated IOP, and progressive retinal ganglion cell pathology. Positional cloning and analysis of a non-complementing allele indicated that non-sense mutations in low density lipoprotein receptor-related protein 2 (lrp2) underlie the mutant phenotype. Lrp2, previously named Megalin, functions as an endocytic receptor for a wide-variety of bioactive molecules including Sonic hedgehog, Bone morphogenic protein 4, retinol-binding protein, vitamin D-binding protein, and apolipoprotein E, among others. Detailed phenotype analyses indicated that as lrp2 mutant fish age, many individuals—but not all—develop high IOP and severe myopia with obviously enlarged eye globes. This results in retinal stretch and prolonged stress to retinal ganglion cells, which ultimately show signs of pathogenesis. Our studies implicate altered Lrp2-mediated homeostasis as important for myopia and other risk factors for glaucoma in humans and establish a new genetic model for further study of phenotypes associated with this disease
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures
Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo
P3-066: The potential predictive value of cyclooxygenase-2 expression and increased risk of gastrointestinal hemorrhage in advanced non-small cell lung cancer patients treated with erlotinib and celecoxib
Character in childhood and early adolescence: models and measurement
In recent years, the construct of character has received substantial attention among developmental scientists, but no consensus exists about the content and structure of character, especially among children and early adolescents. In a study of positive development among racially diverse Cub Scouts in the greater Philadelphia area, we assessed the construct and concurrent validity of a new measure of character, the Assessment of Character in Children and Early Adolescents (ACCEA), among 906 Scouts (mean age = 8.84 years, SD = 1.39 years) and 775 non-Scout boys and girls (mean age = 8.92, SD = 1.64). We identified an eight-correlated-factor model as providing the best fit with our data. We further established measurement invariance and explored latent mean differences for ACCEA scores across two Scout groups (with or without a higher-level program leader), non-Scout boys and non-Scout girls. Girls were generally superior than boys on all character attributes. We further examined concurrent validity of ACCEA by correlating the character attributes with youth sense of school competence, intentional self-regulation and parental perception of youth school performance. We discuss implications for future character research and point to the value of the ACCEA measure being used by practitioners in character development programs
Program innovations and character in Cub Scouts: Findings from Year 1 of a mixed-methods, longitudinal study
Youth development programs seek to promote positive development through mentoring and engaging youth in opportunities for individual growth and community connectedness. We present findings from the initial phase of a mixed-method, longitudinal study aimed at assessing the impact of one such program, Cub Scouts, on character development. We assessed if Scouting, and a recent innovation focused on program quality, are associated with the development of character and other positive outcomes. Participants were 1,083 Scouts and non-Scouts, aged 5-12 years. At the start of the study, there was no difference in indicators of character between Scouts and non-Scouts, once matched through propensity score analyses. Through content analyses of interviews and short-answer questionnaires administered to leaders, we found that leaders’ views of character and of their roles corresponded to those envisioned by Cub Scouts. Implications for character development, and for the role of program components in character development, are discussed