Neutrophil Interstitial Migration

Purpose: Molecular events regulating neutrophil extravasation have been extensively researched and described. However, relatively little is known about extravascular interstitial migration of neutrophils and then, much of what we do know has come from in vitro 2-D or 3-D matrix models. These models are limited by their ability to duplicate the nuances of the physiological or physical native environment. Neutrophils often migrate a considerable distance from the site of extravasation through the avascular corneal stroma to reach the site of injury. This migration involves contact with extracellular matrix and resident keratocytes. Ultrastructural morphometric data suggest neutrophil contacts with keratocytes are mediated by the leukocyte β2 (CD18) integrins and ICAM-1(a β2 ligand). While β1 (CD29) and β3 (CD61) integrin families are also expressed on extravascular migrating neutrophils, in vitro studies have shown that locomotion of activated neutrophils is dependent on integrin binding on 2-D surfaces, but not in 3-D matrixes. The role of integrin binding during in vivo corneal stroma migration has yet to be clearly defined. A greater understanding of this migration holds the promise of a more effective means for modulating neutrophil activity to control inflammation and improve the outcome of wound healing. Additionally, it may elicit details of motility applicable to other types of cells. The purpose of this dissertation is to provide insights into the mechanisms of neutrophil migration through the corneal stroma. Specifically, it addresses the influence of the keratocyte network on migrating neutrophils and the relative contribution of β1 (CD29), β2 (CD18) and β3 (CD61) integrins to neutrophil locomotion in the inflamed mouse cornea. In vivo data obtained using Heidelberg Retinal Tomographer III with Rostock Corneal Module (HRT-RCM) time lapse sequences provided the means, for the first time, to quantify speed and directionality of cellular movement while observing neutrophil interaction with stromal keratocytes in the living eye. Methods: Corneal inflammation was induced in female wild type C57BL/6 mice by mechanical removal of the epithelium using an Algerbrush. Eight hours after injury the corneas were imaged with the HRT-RCM. Scanning sequences provided the means to track individual cells for extended time periods to determine motility characteristics. The contribution of integrin binding to neutrophil migration was assessed by blocking antibody (anti-β1-, β2-, or β3-integrin) or IgG control antibody applied to the cornea at the time of epithelial injury. Image stabilization, cell tracking and movement analysis were accomplished with a custom MatLab program. Results: Time-lapse imaging showed an unequivocal preference for neutrophils to follow the network of keratocytes. Neutrophils in control eyes moved with an average speed of 7.56±0.20 (SE) µm/minute. The average confinement ratio (CR) of the neutrophil population was 0.55±0.02, where a value of 1.0 indicates confinement to a perfectly straight path. Compared to the results from control eyes, anti- β1-integrin antibody resulted in a 31 % reduction in speed (p<0.05) and a 33% reduction in CR (p<0.05), while anti-β2- or β3- integrin antibodies had no significant effect on cell speed or CR. Conclusions: Results clearly show that the keratocyte network is the preferred route for neutrophil migration within the corneal stroma. Contrary to expectations based on previously published histological and in vitro evidence, blockade of β2-integrin does not affect in vivo motility and the same is true for β3-integrin blockade. However, β1 blockade produced a significant, but not total, reduction in cell speed and resulted in migrating cells being less confined to a straight path. Therefore, neutrophil locomotion within the physically confined environment of the corneal stroma does not require integrin binding, though β1 binding facilitates the process.Optometry, College o

Effects of Topically Applied Vitamin D during Corneal Wound Healing

Vitamin D is an important regulator of immune function and largely acts to dampen chronic inflammatory events in a variety of tissues. There is also accumulating evidence that vitamin D acts to enhance initial inflammation, beneficial during both infection and wound healing, and then promotes resolution and prevention of chronic, damaging inflammation. The current study examines the effect of topical vitamin D in a mouse of model of corneal epithelial wound healing, where acute inflammation is necessary for efficient wound closure. At 12 and 18 hours post-wounding, vitamin D treatment significantly delayed wound closure by ~17% and increased infiltration of neutrophils into the central cornea. Basal epithelial cell division, corneal nerve density, and levels of VEGF, TGFβ, IL-1β, and TNFα were unchanged. However, vitamin D increased the production of the anti-microbial peptide CRAMP 12 hours after wounding. These data suggest a possible role for vitamin D in modulating corneal wound healing and have important implications for therapeutic use of vitamin D at the ocular surface

Analyzing DEI Efforts and Curricula in Collegiate Nursing Programs

A diverse, representative health care workforce is crucial to advance health care access, patient satisfaction, and health outcomes, particularly for patients of color. A diverse approach to a nursing education includes teaching students how to adequately care for their patients in ways that take into account their race, gender, ethnicity, sexual orientation or any underrepresented intersectional combination. Studies have shown that healthcare students are exposed to racial bias and prejudiced standards of care within their medical education and placement sites. Implicit bias is prevalent among many academic institutions beginning with the application and recruiting process of potential students. Bias can also take place among current students and faculty which causes some students to feel unsupported in their schooling. Best practices for nursing education programs that center health equity include an anti-racist curriculum, bias awareness training, pathway programs to diversify the healthcare workforce, financial support, and effective mentorship. As Providence College creates a new School of Nursing and Health Sciences, it is imperative that these new programs are built on the foundation of health equity. Our research analyzes nursing programs’ DEI initiatives and curriculum by interviewing current nursing students and DEI administrators and collecting supplemental information from program websites

Assessing risks of polypharmacy involving medications with anticholinergic properties

PURPOSE Anticholinergic burden (ACB), the cumulative effect of anticholinergic medications, is associated with adverse outcomes in older people but is less studied in middle-aged populations. Numerous scales exist to quantify ACB. The aims of this study were to quantify ACB in a large cohort using the 10 most common anticholinergic scales, to assess the association of each scale with adverse outcomes, and to assess overlap in populations identified by each scale. METHODS We performed a longitudinal analysis of the UK Biobank community cohort (502,538 participants, baseline age: 37-73 years, median years of follow-up: 6.2). The ACB was calculated at baseline using 10 scales. Baseline data were linked to national mortality register records and hospital episode statistics. The primary outcome was a composite of all-cause mortality and major adverse cardiovascular event (MACE). Secondary outcomes were all-cause mortality, MACE, hospital admission for fall/fracture, and hospital admission with dementia/delirium. Cox proportional hazards models (hazard ratio [HR], 95% CI) quantified associations between ACB scales and outcomes adjusted for age, sex, socioeconomic status, body mass index, smoking status, alcohol use, physical activity, and morbidity count. RESULTS Anticholinergic medication use varied from 8% to 17.6% depending on the scale used. For the primary outcome, ACB was significantly associated with all-cause mortality/MACE for each scale. The Anticholinergic Drug Scale was most strongly associated with mortality/MACE (HR = 1.12; 95% CI, 1.11-1.14 per 1-point increase in score). The ACB was significantly associated with all secondary outcomes. The Anticholinergic Effect on Cognition scale was most strongly associated with dementia/delirium (HR = 1.45; 95% CI, 1.3-1.61 per 1-point increase). CONCLUSIONS The ACB was associated with adverse outcomes in a middle- to older-aged population. Populations identified and effect size differed between scales. Scale choice influenced the population identified as potentially requiring reduction in ACB in clinical practice or intervention trials

Impact of Sleep and Circadian Disruption on Energy Balance and Diabetes: A Summary of Workshop Discussions

A workshop was held at the National Institute for Diabetes and Digestive and Kidney Diseases with a focus on the impact of sleep and circadian disruption on energy balance and diabetes. The workshop identified a number of key principles for research in this area and a number of specific opportunities. Studies in this area would be facilitated by active collaboration between investigators in sleep/circadian research and investigators in metabolism/diabetes. There is a need to translate the elegant findings from basic research into improving the metabolic health of the American public. There is also a need for investigators studying the impact of sleep/circadian disruption in humans to move beyond measurements of insulin and glucose and conduct more in-depth phenotyping. There is also a need for the assessments of sleep and circadian rhythms as well as assessments for sleep-disordered breathing to be incorporated into all ongoing cohort studies related to diabetes risk. Studies in humans need to complement the elegant short-term laboratory-based human studies of simulated short sleep and shift work etc. with studies in subjects in the general population with these disorders. It is conceivable that chronic adaptations occur, and if so, the mechanisms by which they occur needs to be identified and understood. Particular areas of opportunity that are ready for translation are studies to address whether CPAP treatment of patients with pre-diabetes and obstructive sleep apnea (OSA) prevents or delays the onset of diabetes and whether temporal restricted feeding has the same impact on obesity rates in humans as it does in mice

Pharmaceutical Availability across Levels of Care: Evidence from Facility Surveys in Ghana, Kenya, and Uganda

In this study we use facility-level data from nationally representative surveys conducted in Ghana, Kenya, and Uganda to understand pharmaceutical availability within the three countries

Pharmaceutical availability across levels of care: evidence from facility surveys in Ghana, Kenya, and Uganda.

OBJECTIVE: In this study we use facility-level data from nationally representative surveys conducted in Ghana, Kenya, and Uganda to understand pharmaceutical availability within the three countries. METHODS: In 2012, we conducted a survey to capture information on pharmaceuticals and other facility indicators from over 200 facilities in each country. We analyze data on the availability of pharmaceuticals and quantify its association with various facility-level indicators. We analyze both availability of essential medicines, as defined by the various essential medicine lists (EMLs) of each respective country, and availability of all surveyed pharmaceuticals deemed important for treatment of various high-burden diseases, including those on the EMLs. RESULTS: We find that there is heterogeneity with respect to availability across the three countries with Ghana generally having better availability than Uganda and Kenya. To analyze the relationship between facility-level factors and pharmaceutical stock-out we use a binomial regression model. We find that the factors associated with stock-out vary by country, but across all countries both presence of a laboratory at the facility and presence of a vehicle at the facility are significantly associated with reduced stock-out. CONCLUSION: The results of this study highlight the poor availability of essential medicines across these three countries and suggest more needs to be done to strengthen the supply system so that stock remains uninterrupted

The evolution of pattern camouflage strategies in waterfowl and game birds.

This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/ece3.1482Visual patterns are common in animals. A broad survey of the literature has revealed that different patterns have distinct functions. Irregular patterns (e.g., stipples) typically function in static camouflage, whereas regular patterns (e.g., stripes) have a dual function in both motion camouflage and communication. Moreover, irregular and regular patterns located on different body regions ("bimodal" patterning) can provide an effective compromise between camouflage and communication and/or enhanced concealment via both static and motion camouflage. Here, we compared the frequency of these three pattern types and traced their evolutionary history using Bayesian comparative modeling in aquatic waterfowl (Anseriformes: 118 spp.), which typically escape predators by flight, and terrestrial game birds (Galliformes: 170 spp.), which mainly use a "sit and hide" strategy to avoid predation. Given these life histories, we predicted that selection would favor regular patterning in Anseriformes and irregular or bimodal patterning in Galliformes and that pattern function complexity should increase over the course of evolution. Regular patterns were predominant in Anseriformes whereas regular and bimodal patterns were most frequent in Galliformes, suggesting that patterns with multiple functions are broadly favored by selection over patterns with a single function in static camouflage. We found that the first patterns to evolve were either regular or bimodal in Anseriformes and either irregular or regular in Galliformes. In both orders, irregular patterns could evolve into regular patterns but not the reverse. Our hypothesis of increasing complexity in pattern camouflage function was supported in Galliformes but not in Anseriformes. These results reveal a trajectory of pattern evolution linked to increasing function complexity in Galliformes although not in Anseriformes, suggesting that both ecology and function complexity can have a profound influence on pattern evolution.This work was funded by a Biotechnology and Biological Sciences Research Council studentship to K.L.A.M. and an Australian Postgraduate Award and the Cambridge Overseas Trust to T-LG

Recent cohort effects in suicide in Scotland:A legacy of the 1980s?

Background: Mortality rates are higher in Scotland relative to England and Wales, even after accounting for deprivation. This ‘excess’ mortality is partly due to higher mortality from alcohol-related and drug-related deaths, violence and suicide (particularly in young adults). This study investigated whether cohort effects from exposure to neoliberal politics from the 1980s might explain the recent trends in suicide in Scotland. Methods: We analysed suicide deaths data from 1974 to 2013 by sex and deprivation using shaded contour plots and intrinsic estimator regression modelling to identify and quantify relative age, period and cohort effects. Results: Suicide was most common in young adults (aged around 25–40 years) living in deprived areas, with a younger peak in men. The peak age for suicide fell around 1990, especially for men for whom it dropped quickly from around 50 to 30 years. There was evidence of an increased risk of suicide for the cohort born between 1960 and 1980, especially among men living in the most deprived areas (of around 30%). The cohort at highest risk occurred earlier in the most deprived areas, 1965–1969 compared with 1970–1974. Conclusions: The risk of suicide increased in Scotland for those born between 1960 and 1980, especially for men living in the most deprived areas, which resulted in a rise in age-standardised rates for suicide among young adults during the 1990s. This is consistent with the hypothesis that exposure to neoliberal politics created a delayed negative health impact