65 research outputs found

    Pneumonia identification using nursing home records

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    Pneumonia is a leading cause of death among nursing home residents; consequently, prevention and treatment are important for quality improvement. To be pragmatic, quality improvement depends on sensitive case identification using nursing home records; however, no studies have examined the reliability of different methods of pneumonia case finding from records. The current authors compared three established strategies for defining pneumonia using records from 1,119 residents across 16 nursing homes: recorded diagnosis of pneumonia, modified McGeer criteria (chest x-ray infiltrate plus specified signs/symptoms), and antibiotic prescription plus pneumonia-specific signs. Chart diagnosis detected 107 cases, modified McGeer criteria detected 84 cases, and antibiotic prescription detected 47 cases. Diagnosis included all cases identified by the McGeer criteria and all but one case identified by antibiotic use. Based on findings, recorded diagnosis of pneumonia is a highly sensitive and pragmatic method to ascertain pneumonia in nursing homes, and is recommended for use in quality improvement and research

    Progenitor cells of the rod-free area centralis originate in the anterior dorsal optic vesicle

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    <p>Abstract</p> <p>Background</p> <p>Nervous system development is dependent on early regional specification to create functionally distinct tissues within an initially undifferentiated zone. Within the retina, photoreceptors are topographically organized with rod free area centrales faithfully generated at the centre of gaze. How does the developing eye regulate this placement? Conventional wisdom indicates that the distal tip of the growing optic vesicle (OV) gives rise to the area centralis/fovea. Ectopic expression and ablation studies do not fully support this view, creating a controversy as to the origin of this region. In this study, the lineage of cells in the chicken OV was traced using DiI. The location of labelled cells was mapped onto the retina in relation to the rod-free zone at embryonic (E) 7 and E17.5. The ability to regenerate a rod free area after OV ablation was determined in conjunction with lineage tracing.</p> <p>Results</p> <p>Anterior OV gave rise to cells in nasal retina and posterior OV became temporal retina. The OV distal tip gave rise to cells above the optic nerve head. A dorsal and anterior region of the OV correlated with cells in the developing rod free area centralis. Only ablations including the dorsal anterior region gave rise to a retina lacking a rod free zone. DiI application after ablation indicated that cells movements were greater along the anterior/posterior axis compared with the dorsal/ventral axis.</p> <p>Conclusion</p> <p>Our data support the idea that the chicken rod free area centralis originates from cells located near, but not at the distal tip of the developing OV. Therefore, the hypothesis that the area centralis is derived from cells at the distal tip of the OV is not supported; rather, a region anterior and dorsal to the distal tip gives rise to the rod free region. When compared with other studies of retinal development, our results are supported on molecular, morphological and functional levels. Our data will lead to a better understanding of the mechanisms underlying the topographic organization of the retina, the origin of the rod free zone, and the general issue of compartmentalization of neural tissue before any indication of morphological differentiation.</p

    Black Girls Speak STEM: Counterstories of Informal and Formal Learning Experiences

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    This study presents the interpretations and perceptions of Black girls who participated in I AM STEM – a community-based informal science, technology, engineering, and mathematics (STEM) program. Using narrative inquiry, participants generated detailed accounts of their informal and formal STEM learning experiences. Critical race methodology informed this research to portray the dynamic and complex experiences of girls of color, whose stories have historically been silenced and misrepresented. The data sources for this qualitative study included individual interviews, student reflection journals, samples of student work, and researcher memos, which were triangulated to produce six robust counterstories. Excerpts of the counterstories are presented in this article. The major findings of this research revealed that I AM STEM ignited an interest in STEM learning through field trips and direct engagement in scientific phenomena that allowed the girls to become agentic in continuing their engagement in STEM activities throughout the year. This call to awaken the voices of Black girls to speak casts light on their experiences and challenges as STEM learners ⎯ from their perspectives. The findings confirm that when credence and counterspaces are given to Black girls, they are poised to reveal their luster toward STEM learning. This study provided a space for Black girls to reflect on their STEM learning experiences, formulate new understandings, and make connections between the informal and formal learning environments within the context of their everyday lives, thus offering a more holistic approach to STEM learning that occurs across settings and over a lifetime

    Lhx2 Is Required for Patterning and Expansion of a Distinct Progenitor Cell Population Committed to Eye Development

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    Progenitor cells committed to eye development become specified in the prospective forebrain and develop subsequently into the optic vesicle and the optic cup. The optic vesicle induces formation of the lens placode in surface ectoderm from which the lens develops. Numerous transcription factors are involved in this process, including the eye-field transcription factors. However, many of these transcription factors also regulate the patterning of the anterior neural plate and their specific role in eye development is difficult to discern since eye-committed progenitor cells are poorly defined. By using a specific part of the Lhx2 promoter to regulate Cre recombinase expression in transgenic mice we have been able to define a distinct progenitor cell population in the forebrain solely committed to eye development. Conditional inactivation of Lhx2 in these progenitor cells causes an arrest in eye development at the stage when the optic vesicle induces lens placode formation in the surface ectoderm. The eye-committed progenitor cell population is present in the Lhx2−/− embryonic forebrain suggesting that commitment to eye development is Lhx2-independent. However, re-expression of Lhx2 in Lhx2−/− progenitor cells only promotes development of retinal pigment epithelium cells, indicating that Lhx2 promotes the acquisition of the oligopotent fate of these progenitor cells. This approach also allowed us to identify genes that distinguish Lhx2 function in eye development from that in the forebrain. Thus, we have defined a distinct progenitor cell population in the forebrain committed to eye development and identified genes linked to Lhx2's function in the expansion and patterning of these progenitor cells

    A Genome-Wide Association Study of Diabetic Kidney Disease in Subjects With Type 2 Diabetes

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    dentification of sequence variants robustly associated with predisposition to diabetic kidney disease (DKD) has the potential to provide insights into the pathophysiological mechanisms responsible. We conducted a genome-wide association study (GWAS) of DKD in type 2 diabetes (T2D) using eight complementary dichotomous and quantitative DKD phenotypes: the principal dichotomous analysis involved 5,717 T2D subjects, 3,345 with DKD. Promising association signals were evaluated in up to 26,827 subjects with T2D (12,710 with DKD). A combined T1D+T2D GWAS was performed using complementary data available for subjects with T1D, which, with replication samples, involved up to 40,340 subjects with diabetes (18,582 with DKD). Analysis of specific DKD phenotypes identified a novel signal near GABRR1 (rs9942471, P = 4.5 x 10(-8)) associated with microalbuminuria in European T2D case subjects. However, no replication of this signal was observed in Asian subjects with T2D or in the equivalent T1D analysis. There was only limited support, in this substantially enlarged analysis, for association at previously reported DKD signals, except for those at UMOD and PRKAG2, both associated with estimated glomerular filtration rate. We conclude that, despite challenges in addressing phenotypic heterogeneity, access to increased sample sizes will continue to provide more robust inference regarding risk variant discovery for DKD.Peer reviewe
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