Molecular Mechanisms that establish the eye-specific visual projection

Correct functioning of the nervous system critically depends on the formation of the precise neuronal network. For example, axons of retinal ganglion cells from the right and left eyes project to different domains in the lateral geniculate nucleus of the thalamus. This eye-specific retinogeniculate projection provides the anatomical basis for binocular vision. Nell2 (neural epidermal growth factor (EGF)-like-like-2) is an extracellular glycoprotein that is predominately expressed in the nervous system. Our lab has previously shown that Nell2 acts as an inhibitory axon guidance molecule in the establishment of the eye-specific retinogeniculate projection. The current work aims to identify the Nell2 receptor in the retinal axon guidance. By using immunohistochemistry, we found that the receptor tyrosine kinase Ros1, which binds to Nell2, is expressed in the developing chick retinal ganglion cells. Our results suggest that Ros1 may act as a receptor for Nell2 in the retinal ganglion cells and play a significant role in the establishment of the eye-specific retinogeniculate projection

Identification and characterization of a novel axon guidance receptor in the eye-specific visual projection

Correct functioning of the nervous system critically depends on the formation of the precise neuronal network. In mammals with binocular vision, axons of the retinal ganglion cells from the right and left eyes project to different domains of the lateral geniculate nucleus in the thalamus (Retinogeniculate projection). The eye-specific visual projection provides the anatomical basis for disparity-based stereopsis (perception of depth). However, the molecular mechanism that regulated the eye-specific visual projection is not well understood. Nell2 (neural epidermal growth factor (EGF)-like-like 2) is an extracellular glycoprotein that is predominantly expressed in the nervous system. Our lab has previously shown that Nell2 acts as an inhibitory axon guidance molecule in the establishment of the eye-specific retinogeniculate projection. The current wor aims to identify and functionally characterize the receptor molecule that transduces Nell2-mediated signaling in retinal ganglion cells. By using immunohistochemistry, we found that the receptor tyrosine kinase Ros1, which is known to bind to Nell2, is expressed in developing chick retinal ganglion cells, suggesting that Ros1 may act as a receptor for Nell2 in the visual projection, We are currently generating gene known-down constructs for Ros1, which will be used in in vitro and in vivo axon guidance assays. We expect that this project will elucidate the function of Nell2-Ros1 interaction in establishment of the eye-specific retinogeniculate projection

Understanding vertebrate embryonic development under conditions present in outer space

It is currently unknown whether humans can survive and thrive in outer space, which includes human embryonic development. In this study we investigate vertebrate embryonic development under conditions present in outer space including microgravity and an altered day-and-night cycle using zebrafish and chicken model systems. Zebrafish and chicken model systems are widely used in developmental biology research given their similarity as vertebrates to humans. We aim to analyze the development of brain, muscle and other tissues under conditions of microgravity in both zebrafish and chicken embryos. Additionally, we will analyze zebrafish development under an altered day-and-night cycle (16 sunrises and 16 sunsets per day), and determine whether adult zebrafish can survive and reproduce under these conditions. Zebrafish and chicken embryos will be placed onto a clinostat, which is a device used to simulate a microgravity environment. Embryos will be harvested between 2 and 14 days of incubation on the clinostat, and markers of cell proliferation, death, and differentiation will be analyzed on tissue sections of the brain, skeletal muscle, and other tissues. We expect that our results may allow us to better understand embryonic development under conditions present in outer space, which may shed light on this process in humans

Determining crystal structures through crowdsourcing and coursework

We show here that computer game players can build high-quality crystal structures. Introduction of a new feature into the computer game Foldit allows players to build and real-space refine structures into electron density maps. To assess the usefulness of this feature, we held a crystallographic model-building competition between trained crystallographers, undergraduate students, Foldit players and automatic model-building algorithms. After removal of disordered residues, a team of Foldit players achieved the most accurate structure. Analysing the target protein of the competition, YPL067C, uncovered a new family of histidine triad proteins apparently involved in the prevention of amyloid toxicity. From this study, we conclude that crystallographers can utilize crowdsourcing to interpret electron density information and to produce structure solutions of the highest quality

Organizational interventions in response to duty hour reforms

Abstract Background Changes in resident duty hours in Europe and North America have had a major impact on the internal organizational dynamics of health care organizations. This paper examines, and assesses the impact of, organizational interventions that were a direct response to these duty hour reforms. Methods The academic literature was searched through the SCOPUS database using the search terms “resident duty hours” and “European Working Time Directive,” together with terms related to organizational factors. The search was limited to English-language literature published between January 2003 and January 2012. Studies were included if they reported an organizational intervention and measured an organizational outcome. Results Twenty-five articles were included from the United States (n = 18), the United Kingdom (n = 5), Hong Kong (n = 1), and Australia (n = 1). They all described single-site projects; the majority used post-intervention surveys (n = 15) and audit techniques (n = 4). The studies assessed organizational measures, including relationships among staff, work satisfaction, continuity of care, workflow, compliance, workload, and cost. Interventions included using new technologies to improve handovers and communications, changing staff mixes, and introducing new shift structures, all of which had varying effects on the organizational measures listed previously. Conclusions Little research has assessed the organizational impact of duty hour reforms; however, the literature reviewed demonstrates that many organizations are using new technologies, new personnel, and revised and innovative shift structures to compensate for reduced resident coverage and to decrease the risk of limited continuity of care. Future research in this area should focus on both micro (e.g., use of technology, shift changes, staff mix) and macro (e.g., culture, leadership support) organizational aspects to aid in our understanding of how best to respond to these duty hour reforms

Understanding vertebrate embryonic development under conditions present in outer space

It is currently unknown whether humans can survive and thrive in outer space, which includes human embryonic development. In this study we investigate vertebrate embryonic development under conditions present in outer space including microgravity and an altered day-and-night cycle using zebrafish and chicken model systems. Zebrafish and chicken model systems are widely used in developmental biology research given their similarity as vertebrates to humans. We aim to analyze the development of brain, muscle and other tissues under conditions of microgravity in both zebrafish and chicken embryos. Additionally, we will analyze zebrafish development under an altered day-and-night cycle (16 sunrises and 16 sunsets per day), and determine whether adult zebrafish can survive and reproduce under these conditions. Zebrafish and chicken embryos will be placed onto a clinostat, which is a device used to simulate a microgravity environment. Embryos will be harvested between 2 and 14 days of incubation on the clinostat, and markers of cell proliferation, death, and differentiation will be analyzed on tissue sections of the brain, skeletal muscle, and other tissues. We expect that our results may allow us to better understand embryonic development under conditions present in outer space, which may shed light on this process in humans

Older Adults’ Worry about COVID-19: Associations with Experiences of COVID-19 Among Social Connections

The COVID-19 pandemic has challenged the physical and mental health of older adults, yet it is unknown how much older adults worry about their own exposure. As older adults are at increased risk for severe complications from COVID-19, understanding patterns of worry may inform public health guidelines and interventions for this age group. We investigated older adults’ worry about COVID-19 in the early months of the pandemic and associations with familial/friend’s diagnosis or disease symptoms. Data comes from the baseline (April/May 2020), one-month, and two-month follow-up surveys from the COVID-19 Coping Study, a national longitudinal cohort study of US adults aged ≥55. We used linear regression models to investigate the association between self-reported familial/friend diagnosis or symptoms with pandemic worry, accounting for demographic factors and individual diagnosis or experience of COVID-19 symptoms. Participants (Baseline=4379, 1 month= 2553, 2 month=2682) were 67 years old on average, 72% were female, 5.7% were non-White, and 80.5% had a college degree. At baseline, 26.6% of participants had friends or family who had been diagnosed or experienced symptoms of COVID-19. Having friends or family diagnosed or with symptoms of COVID-19 (B=0.08, SE=0.04, p<.05), being female (B=0.42, SE=0.03, p<.001), and having higher educational attainment (B=0.06, SE=0.02, p<.001) were significantly associated with greater worry about COVID-19. These associations were consistent over 3 months. Understanding if worry about the pandemic correlates with following public health guidelines is a key next step so intervention strategies can prioritize older adults and their social networks

Engaging patients to improve quality of care: a systematic review

Abstract Background To identify the strategies and contextual factors that enable optimal engagement of patients in the design, delivery, and evaluation of health services. Methods We searched MEDLINE, EMBASE, CINAHL, Cochrane, Scopus, PsychINFO, Social Science Abstracts, EBSCO, and ISI Web of Science from 1990 to 2016 for empirical studies addressing the active participation of patients, caregivers, or families in the design, delivery and evaluation of health services to improve quality of care. Thematic analysis was used to identify (1) strategies and contextual factors that enable optimal engagement of patients, (2) outcomes of patient engagement, and (3) patients’ experiences of being engaged. Results Forty-eight studies were included. Strategies and contextual factors that enable patient engagement were thematically grouped and related to techniques to enhance design, recruitment, involvement and leadership action, and those aimed to creating a receptive context. Reported outcomes ranged from educational or tool development and informed policy or planning documents (discrete products) to enhanced care processes or service delivery and governance (care process or structural outcomes). The level of engagement appears to influence the outcomes of service redesign—discrete products largely derived from low-level engagement (consultative unidirectional feedback)—whereas care process or structural outcomes mainly derived from high-level engagement (co-design or partnership strategies). A minority of studies formally evaluated patients’ experiences of the engagement process (n = 12; 25%). While most experiences were positive—increased self-esteem, feeling empowered, or independent—some patients sought greater involvement and felt that their involvement was important but tokenistic, especially when their requests were denied or decisions had already been made. Conclusions Patient engagement can inform patient and provider education and policies, as well as enhance service delivery and governance. Additional evidence is needed to understand patients’ experiences of the engagement process and whether these outcomes translate into improved quality of care. Registration N/A (data extraction completed prior to registration on PROSPERO)

Additional file 1: of Engaging patients to improve quality of care: a systematic review

Table S3. PRISMA checklist. (DOC 63 kb