Bilateral absence of the musculocutaneous nerve : implications for humerus fracture and atypical median nerve palsy

The absence of the musculocutaneous nerve represents a failure of the nerve to depart from the median nerve during early development. During a routine dissection of a 66-year-old white female cadaver, a bilateral absence of the musculocutaneous nerve was observed in the upper limbs. Muscles of the anterior flexor compartments of the arms including biceps brachii and brachialis were supplied by branches of the median nerve. The lateral cutaneous nerve of the forearm also branched from the median nerve. In a clinical case of a particularly high median nerve injury, a variation of an absent musculocutaneous nerve may not only result in typical median nerve palsy of the forearm and hand, but palsy in the arm that would manifest as deficiencies in both shoulder and elbow flexion as well as cutaneous sensory loss from the lateral forearm

Prenatal and Early, but Not Late, Postnatal Exposure of Mice to Sidestream Tobacco Smoke Increases Airway Hyperresponsiveness Later in Life

Background Cigarette smoke exposure in utero and during early postnatal development increases the incidence of asthma and airway hyperresponsiveness (AHR) later in life, suggesting that a possible critical period of developmental sensitivity exists in the prenatal and early postnatal periods. Objective We investigated mechanisms of susceptibility during critical developmental periods to sidestream smoke (SS) exposure and evaluated the possible effects of SS on neural responses. Methods We exposed three different age groups of mice to either SS or filtered air (FA) for 10 consecutive days beginning on gestation day (GD) 7 by maternal exposure or beginning on postnatal day (PND) 2 or PND21 by direct inhalation. Lung function, airway substance P (SP) innervation, and nerve growth factor (NGF) levels in broncho alveolar lavage fluid were measured after a single SS exposure on PND59. Results Methacholine (MCh) dose response for lung resistance (RL) was significantly elevated, and dynamic pulmonary compliance (Cdyn) was significantly decreased, in the GD7 and PND2 SS exposure groups compared with the FA groups after SS exposure on PND59. At the same time points, the percent area of SP nerve fibers in tracheal smooth muscle and the levels of NGF were significantly elevated. MCh dose–response curves for RL and Cdyn, SP nerve fiber density, and the level of NGF were not significantly changed in the PND21 exposure group after SS exposure on PND59. Conclusions These results suggest that a critical period of susceptibility to SS exposure exists in the prenatal and early postnatal period of development in mice that results in increased SP innervation, increased NGF levels in the airway, and enhanced MCh AHR later in life

Prenatal and Early, but Not Late, Postnatal Exposure of Mice to Sidestream Tobacco Smoke Increases Airway Hyperresponsiveness Later in Life

Background Cigarette smoke exposure in utero and during early postnatal development increases the incidence of asthma and airway hyperresponsiveness (AHR) later in life, suggesting that a possible critical period of developmental sensitivity exists in the prenatal and early postnatal periods. Objective We investigated mechanisms of susceptibility during critical developmental periods to sidestream smoke (SS) exposure and evaluated the possible effects of SS on neural responses. Methods We exposed three different age groups of mice to either SS or filtered air (FA) for 10 consecutive days beginning on gestation day (GD) 7 by maternal exposure or beginning on postnatal day (PND) 2 or PND21 by direct inhalation. Lung function, airway substance P (SP) innervation, and nerve growth factor (NGF) levels in broncho alveolar lavage fluid were measured after a single SS exposure on PND59. Results Methacholine (MCh) dose response for lung resistance (RL) was significantly elevated, and dynamic pulmonary compliance (Cdyn) was significantly decreased, in the GD7 and PND2 SS exposure groups compared with the FA groups after SS exposure on PND59. At the same time points, the percent area of SP nerve fibers in tracheal smooth muscle and the levels of NGF were significantly elevated. MCh dose–response curves for RL and Cdyn, SP nerve fiber density, and the level of NGF were not significantly changed in the PND21 exposure group after SS exposure on PND59. Conclusions These results suggest that a critical period of susceptibility to SS exposure exists in the prenatal and early postnatal period of development in mice that results in increased SP innervation, increased NGF levels in the airway, and enhanced MCh AHR later in life

Early postnatal ozone exposure alters rat nodose and jugular sensory neuron development

Sensory neurons originating in nodose and jugular ganglia that innervate airway epithelium (airway neurons) play a role in inflammation observed following exposure to inhaled environmental irritants such as ozone (O3). Airway neurons can mediate airway inflammation through the release of the neuropeptide substance P (SP). While susceptibility to airway irritants is increased in early life, the developmental dynamics of afferent airway neurons are not well characterized. The hypothesis of this study was that airway neuron number might increase with increasing age, and that an acute, early postnatal O3 exposure might increase both the number of sensory airway neurons as well as the number SP-containing airway neurons. Studies using Fischer 344 rat pups were conducted to determine if age or acute O3 exposure might alter airway neuron number. Airway neurons in nodose and jugular ganglia were retrogradely labeled, removed, dissociated, and counted by means of a novel technique employing flow cytometry. In Study 1, neuron counts were conducted on postnatal days (PD) 6, 10, 15, 21, and 28. Numbers of total and airway neurons increased significantly between PD6 and PD10, then generally stabilized. In Study 2, animals were exposed to O3 (2 ppm) or filtered air (FA) on PD5 and neurons were counted on PD10, 15, 21, and 28. O3-exposed animals displayed significantly less total neurons on PD21 than FA controls. This study shows that age-related changes in neuron number occur, and that an acute, early postnatal O3 exposure significantly alters sensory neuron development

Essential Content for Teaching Implementation Practice in Healthcare: A Mixed-Methods Study of Teams Offering Capacity-Building Initiatives

Background Applying the knowledge gained through implementation science can support the uptake of research evidence into practice; however, those doing and supporting implementation (implementation practitioners) may face barriers to applying implementation science in their work. One strategy to enhance individuals’ and teams’ ability to apply implementation science in practice is through training and professional development opportunities (capacity-building initiatives). Although there is an increasing demand for and offerings of implementation practice capacity-building initiatives, there is no universal agreement on what content should be included. In this study we aimed to explore what capacity-building developers and deliverers identify as essential training content for teaching implementation practice. Methods We conducted a convergent mixed-methods study with participants who had developed and/or delivered a capacity-building initiative focused on teaching implementation practice. Participants completed an online questionnaire to provide details on their capacity-building initiatives; took part in an interview or focus group to explore their questionnaire responses in depth; and offered course materials for review. We analyzed a subset of data that focused on the capacity-building initiatives’ content and curriculum. We used descriptive statistics for quantitative data and conventional content analysis for qualitative data, with the data sets merged during the analytic phase. We presented frequency counts for each category to highlight commonalities and differences across capacity-building initiatives. Results Thirty-three individuals representing 20 capacity-building initiatives participated. Study participants identified several core content areas included in their capacity-building initiatives: (1) taking a process approach to implementation; (2) identifying and applying implementation theories, models, frameworks, and approaches; (3) learning implementation steps and skills; (4) developing relational skills. In addition, study participants described offering applied and pragmatic content (e.g., tools and resources), and tailoring and evolving the capacity-building initiative content to address emerging trends in implementation science. Study participants highlighted some challenges learners face when acquiring and applying implementation practice knowledge and skills. Conclusions This study synthesized what experienced capacity-building initiative developers and deliverers identify as essential content for teaching implementation practice. These findings can inform the development, refinement, and delivery of capacity-building initiatives, as well as future research directions, to enhance the translation of implementation science into practice

Gene content evolution in the arthropods

Arthropods comprise the largest and most diverse phylum on Earth and play vital roles in nearly every ecosystem. Their diversity stems in part from variations on a conserved body plan, resulting from and recorded in adaptive changes in the genome. Dissection of the genomic record of sequence change enables broad questions regarding genome evolution to be addressed, even across hyper-diverse taxa within arthropods. Using 76 whole genome sequences representing 21 orders spanning more than 500 million years of arthropod evolution, we document changes in gene and protein domain content and provide temporal and phylogenetic context for interpreting these innovations. We identify many novel gene families that arose early in the evolution of arthropods and during the diversification of insects into modern orders. We reveal unexpected variation in patterns of DNA methylation across arthropods and examples of gene family and protein domain evolution coincident with the appearance of notable phenotypic and physiological adaptations such as flight, metamorphosis, sociality, and chemoperception. These analyses demonstrate how large-scale comparative genomics can provide broad new insights into the genotype to phenotype map and generate testable hypotheses about the evolution of animal diversity

Chasing ambiguity: critical reflections on working with dance graduates

This paper questions whether are we able to foster uncertainty and ambiguity within higher education arts programmes, specifically alongside current institutional demands and embedded pedagogies. If not, then what effect does this have on current dance graduates? I attend to these questions through critical reflections upon my work as a pedagogue, specifically reflecting upon a series of artistic choreographic projects working in collaboration with recent dance graduates. During these choreographic projects, my interactions with the graduates illuminated their struggle to operate within ambiguous creative spaces outside of institutional environments. This struggle manifest in turbulent working relationships and highlighted perceived contradictions or ‘gaps’ between what creative arts education attempts to teach, how it is taught within the institution, and what graduates demonstrate within professional creative practice. Through a recognition and critique of these ‘gaps’, I question whether it is possible to actively work within these ‘messy’ spaces, to chase the ambiguities present, in order to foster sustainable dance graduates that can work more visibly alongside academics and professionals to shape the current dance landscape

Hundreds of variants clustered in genomic loci and biological pathways affect human height

Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.

The meaning and measurement of implementation climate

<p>Abstract</p> <p>Background</p> <p>Climate has a long history in organizational studies, but few theoretical models integrate the complex effects of climate during innovation implementation. In 1996, a theoretical model was proposed that organizations could develop a positive climate for implementation by making use of various policies and practices that promote organizational members' means, motives, and opportunities for innovation use. The model proposes that implementation climate--or the extent to which organizational members perceive that innovation use is expected, supported, and rewarded--is positively associated with implementation effectiveness. The implementation climate construct holds significant promise for advancing scientific knowledge about the organizational determinants of innovation implementation. However, the construct has not received sufficient scholarly attention, despite numerous citations in the scientific literature. In this article, we clarify the meaning of implementation climate, discuss several measurement issues, and propose guidelines for empirical study.</p> <p>Discussion</p> <p>Implementation climate differs from constructs such as organizational climate, culture, or context in two important respects: first, it has a strategic focus (implementation), and second, it is innovation-specific. Measuring implementation climate is challenging because the construct operates at the organizational level, but requires the collection of multi-dimensional perceptual data from many expected innovation users within an organization. In order to avoid problems with construct validity, assessments of within-group agreement of implementation climate measures must be carefully considered. Implementation climate implies a high degree of within-group agreement in climate perceptions. However, researchers might find it useful to distinguish implementation climate level (the average of implementation climate perceptions) from implementation climate strength (the variability of implementation climate perceptions). It is important to recognize that the implementation climate construct applies most readily to innovations that require collective, coordinated behavior change by many organizational members both for successful implementation and for realization of anticipated benefits. For innovations that do not possess these attributes, individual-level theories of behavior change could be more useful in explaining implementation effectiveness.</p> <p>Summary</p> <p>This construct has considerable value in implementation science, however, further debate and development is necessary to refine and distinguish the construct for empirical use.</p