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Genetic factors related to pregnancy-related traits are understudied, especially in ancestrally diverse cohorts. To assess maternal contributions to hypertensive disorders of pregnancy (HDP), we performed a multi-ancestry genome-wide association study (GWAS) of HDP in data from the North Carolina-based Personalized Environment and Genes Study (PEGS) cohort with validation in the UK Biobank (UKBB). The GWAS revealed two maternal loci associated with HDP at the genome-wide significance level. The lead independent variants were rs114954125 on chromosome 2 (near LRP1B; odds ratio [OR] [95% confidence interval {CI}]): 2.96 [2.02-4.34]; p = 2.82 × 10 -8 ) and rs61176331 on chromosome 3 (on RARB; OR (95% CI): 3.08 (2.12-4.48); p = 3.52 × 10 -9 ). We validated the associations near RARB with a meta-analysis of PEGS and the UKBB. We also identified cis-expression quantitative trait loci in the candidate region associated with decreased RARB expression in macrophage cells exposed to Salmonella. Chromatin mapping in FUMA identified a significant interaction within chromosome 3's enhancer and open chromatin regions, with strong effects observed for RARB and H3P10 gene regulation in mesendoderm cells, mesenchymal stem cells, and trophoblast-like stem cells. We applied existing polygenic scores (PGS) for preeclampsia and gestational hypertension and found that the scores were significantly associated with HDP in PEGS. The findings demonstrate the power of multi-ancestry studies for genetic discovery and highlight the relationship between immune response, regulation, and HDP and the utility of PGS for risk prediction. (PEGS is registered at ClinicalTrials.gov: NCT00341237.)., Competing Interests: Declaration of interests The authors declare no competing interests., (Published by Elsevier Inc.)

Background: Elevated maternal serum sFLT1 (soluble fms-like tyrosine kinase 1) has a key role in the pathophysiology of preeclampsia. We sought to determine the relationship between the maternal and fetal genome and maternal levels of sFLT1 at 12, 20, 28, and 36 weeks of gestational age (wkGA)., Methods: We studied a prospective cohort of nulliparous women (3968 mother-child pairs). We related maternal and fetal genotype to the adjusted sFLT1 Z score and sFLT1:placental growth factor (PlGF) ratio Z score at each wkGA and the change in the Z score between 28 and 36 wkGA (Δ36-28). We studied genetic variants from a previous fetal genome-wide association study of preeclampsia and an externally defined polygenic score from a maternal genome-wide association study of preeclampsia., Results: Four variants from the fetal preeclampsia genome-wide association study were positively associated with sFLT1 and sFLT1:PlGF Z score at 36 wkGA, and FLT1 enhancer single-nucleotide polymorphisms were associated with increased Δ36-28 of sFLT1. The associations were specific for the fetal genome or stronger for the fetal than the maternal genome. An increased risk of preeclampsia based on the maternal polygenic score for preeclampsia was associated with lower levels of sFLT1 and sFLT1:PlGF ratio in the first trimester and a greater Δ36-28 for sFLT1., Conclusions: The current data are consistent with a causal association between sFLT1 released by the placenta in late pregnancy and the pathophysiology of preeclampsia. The data are also consistent with maternal components to the protective effect of high sFLT1 in the first trimester and the rise in third-trimester sFLT1 levels and preeclampsia.

Vitamin D3, a prohormone, is converted to circulating calcidiol and then to calcitriol, the hormone that binds to the vitamin D receptor (VDR) (a nuclear transcription factor). Polymorphic genetic sequence variants of the VDR are associated with an increased risk of breast cancer and melanoma. However, the relationship between VDR allelic variants and the risk of squamous cell carcinoma and actinic keratosis remains unclear. We examined the associations between two VDR polymorphic sites, Fok1 and Poly-A, and serum calcidiol levels, actinic keratosis lesion incidence, and the history of cutaneous squamous cell carcinoma in 137 serially enrolled patients. By evaluating the Fok1 (F) and (f) alleles and the Poly-A long (L) and short (S) alleles together, a strong association between genotypes FFSS or FfSS and high calcidiol serum levels (50.0 ng/ml) was found; conversely, ffLL patients showed very low calcidiol levels (29.1 ng/ml). Interestingly, the FFSS and FfSS genotypes were also associated with reduced actinic keratosis incidence. For Poly-A, additive modeling showed that Poly-A (L) is a risk allele for squamous cell carcinoma, with an OR of 1.55 per copy of the L allele. We conclude that actinic keratosis and squamous cell carcinoma should be added to the list of squamous neoplasias that are differentially regulated by the VDR Poly-A allele., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Asthma is a chronic disease of the airways that impairs normal breathing. The etiology of asthma is complex and involves multiple factors, including the environment and genetics, especially the distinct genetic architecture associated with ancestry. Compared to early-onset asthma, little is known about genetic predisposition to late-onset asthma. We investigated the race/ethnicity-specific relationship among genetic variants within the major histocompatibility complex (MHC) region and late-onset asthma in a North Carolina-based multiracial cohort of adults. Methods: We stratified all analyses by self-reported race (i.e., White and Black) and adjusted all regression models for age, sex, and ancestry. We conducted association tests within the MHC region and performed fine-mapping analyses conditioned on the race/ethnicity-specific lead variant using whole-genome sequencing (WGS) data. We applied computational methods to infer human leukocyte antigen (HLA) alleles and residues at amino acid positions. We replicated findings in the UK Biobank. Results: The lead signals, rs9265901 on the 5' end of HLA-B, rs55888430 on HLA-DOB, and rs117953947 on HCG17, were significantly associated with late-onset asthma in all, White, and Black participants, respectively (OR = 1.73, 95%CI: 1.31 to 2.14, p = 3.62 × 10 -5 ; OR = 3.05, 95%CI: 1.86 to 4.98, p = 8.85 × 10 -6 ; OR = 19.5, 95%CI: 4.37 to 87.2, p = 9.97 × 10 -5 , respectively). For the HLA analysis, HLA-B*40:02 and HLA-DRB1*04:05, HLA-B*40:02, HLA-C*04:01, and HLA-DRB1*04:05, and HLA-DRB1*03:01 and HLA-DQB1 were significantly associated with late-onset asthma in all, White, and Black participants. Conclusion: Multiple genetic variants within the MHC region were significantly associated with late-onset asthma, and the associations were significantly different by race/ethnicity group., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lee, Choi, Burkholder, Perera, Mack, Miller, Fessler, Cook, Karmaus, Nakano, Garantziotis, Madenspacher, House, Akhtari, Schmitt, Fargo, Hall and Motsinger-Reif.)

Objective: This study tested the hypothesis that obesity and metabolic abnormalities correlate with background parenchymal enhancement (BPE), the volume and intensity of enhancing fibroglandular breast tissue on dynamic contrast-enhanced magnetic resonance imaging., Methods: Participants included 59 premenopausal women at high risk of breast cancer. Obesity was defined as BMI ≥ 30 kg/m 2 . Metabolic parameters included dual-energy x-ray absorptiometry-quantified body composition, plasma biomarkers of insulin resistance, adipokines, inflammation, lipids, and urinary sex hormones. BPE was assessed using computerized algorithms on dynamic contrast-enhanced magnetic resonance imaging., Results: BMI was positively correlated with BPE (r = 0.69; p < 0.001); participants with obesity had higher BPE than those without obesity (404.9 ± 189.6 vs. 261.8 ± 143.8 cm 2 ; Δ: 143.1 cm 2 [95% CI: 49.5-236.7]; p = 0.003). Total body fat mass (r = 0.68; p < 0.001), body fat percentage (r = 0.64; p < 0.001), visceral adipose tissue area (r = 0.65; p < 0.001), subcutaneous adipose tissue area (r = 0.60; p < 0.001), insulin (r = 0.59; p < 0.001), glucose (r = 0.35; p = 0.011), homeostatic model of insulin resistance (r = 0.62; p < 0.001), and leptin (r = 0.60; p < 0.001) were positively correlated with BPE. Adiponectin (r = -0.44; p < 0.001) was negatively correlated with BPE. Plasma biomarkers of inflammation and lipids and urinary sex hormones were not correlated with BPE., Conclusions: In premenopausal women at high risk of breast cancer, increased BPE is associated with obesity, insulin resistance, leptin, and adiponectin., (© 2023 The Obesity Society.)

Background: The COVID-19 pandemic has caused morbidity and mortality, particularly among vulnerable populations. We aimed to assess social and demographic characteristics associated with COVID-19 severity among symptomatic participants during pregnancy., Methods: The International Registry of Coronavirus Exposure in Pregnancy is a multinational, longitudinal observational cohort study of adult participants tested for SARS-CoV-2 or who received clinical diagnosis of COVID-19 during pregnancy (NCT04366986). Disease severity status of mild, moderate, or severe was determined based on symptoms and healthcare utilization. Stratified by current versus recent pregnancy at enrollment, univariate mixed-effects logistic regression modeling was used to characterize association between social and demographic characteristics with COVID-19 severity, using a cumulative mixed effect model with country as a random effect., Results: The odds of developing more severe COVID-19 (odds ratio [95% confidence interval]) were higher among participants with lower socioeconomic status (poor: 2.72 [2.01,3.69]; lower-middle class: 2.07 [1.62,2.65] vs wealthy), among participants with lower educational attainment (high school: 1.68 [1.39,2.03]; < high school (1.77 [1.25,2.51] vs graduate education). Participants over 25 years of age had lower odds of severe COVID-19 versus participants < 25 years (25-34: 0.69 [0.56,0.85]; 35-50: 0.62 [0.48,0.80]). Employment in food services was also associated with increased odds of more severe COVID-19, whereas employment in healthcare and within home, and primiparity were associated with lower severity., Conclusions: Findings suggest that employment setting and economic status have strong associations with COVID-19 severity, which warrants considering social determinants of health in the context of assessing risk factors of more severe COVID-19 during pregnancy., Trial Registration: IRCEP was registered with the European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP) [EUPAS37360] and clinicaltrials.gov [NCT04366986]., (© 2022. The Author(s).)

Normal myofibroblast differentiation is critical for proper skin wound healing. Neoexpression of α-smooth muscle actin (α-SMA), a marker for myofibroblast differentiation, is driven by transforming growth factor (TGF)-β receptor-mediated signaling. Hyaluronan and its three synthesizing enzymes, hyaluronan synthases (Has 1, 2, and 3), also participate in this process. Closure of skin wounds is significantly accelerated in Has1/3 double-knockout (Has1/3-null) mice. Herein, TGF-β activity and dermal collagen maturation were increased in Has1/3-null healing skin. Cultures of primary skin fibroblasts isolated from Has1/3-null mice had higher levels of TGF-β activity, α-SMA expression, and phosphorylation of p38 mitogen-activated protein kinase at Thr180/Tyr182, compared with wild-type fibroblasts. p38α mitogen-activated protein kinase was a necessary element in a noncanonical TGF-β receptor signaling pathway driving α-SMA expression in Has1/3-null fibroblasts. Myocardin-related transcription factor (MRTF), a cofactor that binds to the transcription factor serum response factor (SRF), was also critical. Nuclear localization of MRTF was increased, and MRTF binding to SRF was enhanced in Has1/3-null fibroblasts. Inhibition of MRTF or SRF expression by RNA interference suppresses α-SMA expression at baseline and diminished its overexpression in Has1/3-null fibroblasts. Interestingly, total matrix metalloproteinase activity was increased in healing skin and fibroblasts from Has1/3-null mice, possibly explaining the increased TGF-β activation., (Copyright © 2022 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Interprofessional experiences during medical school are often delivered during pre-clinical years, but less is known about the value of clinical students. Our institution implemented a specialty-specific interprofessiona curriculum during Residency Preparation Courses (RPCs) for senior students including didactics, clinical experiences, and a simulated paging curriculum. Our aim was to determine whether this intervention improved perceptions of interprofesiona roles. We distributed anonymous surveys before (pre-survey) and after (post-survey, collected within 2 weeks of course completion) the RPC to 90 students with questions related to interprofessional roles using a 5-point scale (1 =  strongly disagree , 5 =  strongly agree ). Three months after the start of residency, we sent follow-up surveys inquiring about the usefulness of RPC components (1 =  not at all useful , 5 =  extremely useful ). Response rates were 84.4% pre-survey, 63.3% post-survey, and 41.1% follow-up survey. Post-surveys indicated improvement in self-reported ability in all domains: understanding one's contributions to interprofessional teams (3.9 to 4.4, p < .0001), understanding other team members' contributions (3.9 to 4.4, p < .0001), learning from interprofessional team members (4.2 to 4.6, p = .0002), accounting for interprofessional perspectives (4.2 to 4.6, p < .0001), and co-developing effective care plans (3.9 to 4.4, p < .0001). Follow-up surveys rated clinical experiences as slightly-to-moderately useful (2.3 ± 1.0) and paging curriculum very-to-extremely useful (4.3 ± 1.0). This study demonstrates the value of interprofessional education for advanced students.

Building on nascent literature examining the health-related effects of vicarious structural racism, we examined indirect exposure to the Flint Water Crisis (FWC) as a predictor of birth outcomes in Michigan communities outside of Flint, where residents were not directly exposed to lead-contaminated water. Using linear regression models, we analyzed records for all singleton live births in Michigan from 2013 to 2016, excluding Flint, to determine whether birth weight (BW), gestational age (GA), and size-for-gestational-age (SzGA) decreased among babies born to Black people, but not among babies born to White people, following the highly publicized January 2016 emergency declaration in Flint. In adjusted regression models, BW and SzGA were lower for babies born to both Black and White people in the 37 weeks following the emergency declaration compared to the same 37-week periods in the previous 3 years. There were no racial differences in the association of exposure to the emergency declaration with BW or SzGA. Among infants born to Black people, GA was 0.05 weeks lower in the 37-week period following the emergency declaration versus the same 37-week periods in the previous 3 years (95% CI: -0.09, -0.01; p = 0.0177), while there was no change in GA for infants born to White people following the emergency declaration (95% CI: -0.01, 0.03; p = 0.6962). The FWC, which was widely attributed to structural racism, appears to have had a greater impact, overall, on outcomes for babies born to Black people. However, given the frequency of highly publicized examples of anti-Black racism over the study period, it is difficult to disentangle the effects of the FWC from the effects of other racialized stressors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer EC declared a shared affiliation with the authors KA, JM, NF, and BN to the handling editor at the time of review., (Copyright © 2022 Allgood, Mack, Novak, Abdou, Fleischer and Needham.)

In this paper, we provide a brief overview of the history, organizational structure, and current operational state of our blended academic and community-model breast service. We review the challenges inherent to governance and management of a "matrix" organization practice model such as ours, and discuss the ways in which the leadership of our evolving blended practice are addressing those challenges collaboratively., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Aim: Thrombosis of bridging veins has been suggested to be a marker of bridging vein rupture, and thus AHT, in infants with subdural haematoma., Methods: This is a non-systematic review based on Pubmed search, secondary reference tracking and authors' own article collections., Results: Radiological studies asserting that imaging signs of cortical vein thrombosis were indicative of traumatic bridging vein rupture were unreliable as they lacked pathological verification of either thrombosis or rupture, and paid little regard to medical conditions other than trauma. Autopsy attempts at confirmation of ruptured bridging veins as the origin of SDH were fraught with difficulty. Moreover, microscopic anatomy demonstrated alternative non-traumatic sources of a clot in or around bridging veins. Objective pathological observations did not support the hypothesis that a radiological finding of bridging vein thrombosis was the result of traumatic rupture by AHT. No biomechanical models have produced reliable and reproducible data to demonstrate that shaking alone can be a cause of bridging vein rupture., Conclusion: There is no conclusive evidence supporting the hypothesis that diagnostic imaging showing thrombosed bridging veins in infants correlates with bridging vein rupture. Hence, there is no literature support for the use of thrombosis as a marker for AHT., (© 2021 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)

Introduction: Postgraduate trainees address outpatient telephone calls (OTCs) with little prior training. This study determines the skills necessary for OTCs and examines whether a video intervention improves medical students' performance on simulated OTCs., Materials and Methods: We utilized a Delphi technique to determine skills needed for OTCs and created a 9-min video teaching these skills. Senior medical students were randomized to Intervention (viewed video) and Control (did not view video) groups. Students were assessed pre-/post-intervention on simulated OTCs. The primary outcome was the between-group difference in improvement., Results: The Delphi yielded 34 important skills with the highest focus on communication ( n  = 13) and triage ( n  = 6). Seventy-two students completed assessments (Control, n  = 41; Intervention, n  = 31). The score (mean ± SD) improved 4.3% in the Control group (62.3 ± 14.3% to 66.6 ± 25.0%) and 12.2% in the Intervention group (60.7 ± 15.2% to 72.9 ± 20.4%, p  = 0.15). The effect size measured by Cohen's d was 0.55, considered effective (> 0.33) for an educational intervention., Conclusions: This project fills a gap in OTC training. The use of the Delphi technique, intervention development based on the results, and evaluation of efficacy is a process that could be reproduced for other educational gaps., Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-021-01331-w., Competing Interests: Conflict of InterestThe authors declare no competing interests., (© International Association of Medical Science Educators 2021.)

Previously, we demonstrated low-dose antithymocyte globulin (ATG) and granulocyte colony-stimulating factor (GCSF) immunotherapy preserved C-peptide for 2 years in a pilot study of patients with established type 1 diabetes ( n = 25). Here, we evaluated the long-term outcomes of ATG/GCSF in study participants with 5 years of available follow-up data ( n = 15). The primary end point was area under the curve (AUC) C-peptide during a 2-h mixed-meal tolerance test. After 5 years, there were no statistically significant differences in AUC C-peptide when comparing those who received ATG/GCSF versus placebo ( P = 0.41). A modeling framework based on mean trajectories in C-peptide AUC over 5 years, accounting for differing trends between groups, was applied to recategorize responders ( n = 9) and nonresponders ( n = 7). ATG/GCSF reponders demonstrated nearly unchanged HbA 1c over 5 years (mean [95% CI] adjusted change 0.29% [-0.69%, 1.27%]), but the study was not powered for comparisons against nonresponders 1.75% (-0.57%, 4.06%) or placebo recipients 1.44% (0.21%, 2.66%). These data underscore the importance of long-term follow-up in previous and ongoing phase 2 trials of low-dose ATG in recent-onset type 1 diabetes., (© 2021 by the American Diabetes Association.)

Background: We performed a phenome-wide association study to identify pre-existing conditions related to Coronavirus disease 2019 (COVID-19) prognosis across the medical phenome and how they vary by race., Methods: The study is comprised of 53,853 patients who were tested/diagnosed for COVID-19 between 10 March and 2 September 2020 at a large academic medical center., Results: Pre-existing conditions strongly associated with hospitalization were renal failure, pulmonary heart disease, and respiratory failure. Hematopoietic conditions were associated with intensive care unit (ICU) admission/mortality and mental disorders were associated with mortality in non-Hispanic Whites. Circulatory system and genitourinary conditions were associated with ICU admission/mortality in non-Hispanic Blacks., Conclusions: Understanding pre-existing clinical diagnoses related to COVID-19 outcomes informs the need for targeted screening to support specific vulnerable populations to improve disease prevention and healthcare delivery.

Background and Aim: Non-alcoholic steatohepatitis (NASH), which can lead to liver failure, requires liver biopsies to follow and is difficult to treat. Our goal was to assess metabolic syndrome (MetS) severity as a predictor of treatment success and a marker of response., Methods: We assessed data from the Pioglitazone, Vitamin E, or Placebo for NASH Study, in which individuals with biopsy-confirmed NASH were randomized to receive pioglitazone, vitamin E, or placebo for 96 weeks. We assessed associations of a sex-specific and race/ethnicity-specific MetS severity Z-score (MetS-Z) at baseline and 48 weeks with biopsy-determined endpoint of NASH resolution at 96 weeks., Results: Baseline MetS-Z was inversely associated with odds of NASH resolution (odds ratio [OR] per 1 SD of MetS-Z: 0.47, 95% confidence interval [CI] 0.28, 0.79). Decrease in MetS-Z during initial 48-week intervention was greatest for pioglitazone treatment (effect size: -0.31, 95% CI -0.15, -0.48) and for vitamin E tended toward being greater for those with versus without NASH resolution (-0.18 vs -0.05). Overall, 48-week change in MetS-Z was associated with NASH resolution (OR per 1-SD change: 0.53, 95% CI 0.33, 0.85), although this was attenuated in models that included transaminases, which remained linked to treatment success (OR by change-in-aspartate aminotransferase Z-score: 0.38, 95% CI 0.19, 0.76)., Conclusions: Individuals with more severe metabolic derangement at baseline were less likely to exhibit NASH resolution, suggesting that individuals may have a threshold of MetS severity beyond which successful treatment is unlikely. As an integrated marker of metabolic abnormalities, MetS-Z was correlated with successful treatment, although transaminases were a more consistent marker of NASH resolution., (© 2020 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

We investigated how loss of TSG-6 affects wound closure and skin inflammation. TSG-6 has several known biological functions, including the enzymatic transfer of heavy-chain proteins from inter-α-trypsin inhibitor to hyaluronan to form heavy-chain protein-hyaluronan complexes. TSG-6 and heavy-chain protein-hyaluronan are constitutively expressed in normal skin and increase post-wounding but are completely absent in TSG-6-null mice. Wound closure rates are significantly delayed in TSG-6-null mice relative to wildtype mice. Neutrophil recruitment is delayed in early wounds (12 hours and day 1), whereas late wounds (day 7) show elevated neutrophil accumulation. In addition, granulation phase resolution is delayed, with persistent blood vessels and reduced dermal collagen at 10 days. The proinflammatory cytokine TNFα is elevated >3-fold in unwounded TSG-6-null skin and increases further after wounding (from 12 hours to 7 days) before returning to baseline by day 10. Other cytokines examined, such as IL-6, IL-10, and monocyte chemotactic protein-1, showed no consistent differences. Reintroduction of TSG-6 into TSG-6-null wounds rescues both the delay in wound closure and the aberrant neutrophil phenotype. In summary, our study indicates that TSG-6 plays an important role in regulating wound closure and inflammation during cutaneous wound repair., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Importance: Black patients are overrepresented in the number of COVID-19 infections, hospitalizations, and deaths in the US. Reasons for this disparity may be due to underlying comorbidities or sociodemographic factors that require further exploration., Objective: To systematically determine patient characteristics associated with racial/ethnic disparities in COVID-19 outcomes., Design, Setting, and Participants: This retrospective cohort study used comparative groups of patients tested or treated for COVID-19 at the University of Michigan from March 10, 2020, to April 22, 2020, with an outcome update through July 28, 2020. A group of randomly selected untested individuals were included for comparison. Examined factors included race/ethnicity, age, smoking, alcohol consumption, comorbidities, body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), and residential-level socioeconomic characteristics., Exposure: In-house polymerase chain reaction (PCR) tests, commercial antibody tests, nasopharynx or oropharynx PCR deployed by the Michigan Department of Health and Human Services and reverse transcription-PCR tests performed in external labs., Main Outcomes and Measures: The main outcomes were being tested for COVID-19, having test results positive for COVID-19 or being diagnosed with COVID-19, being hospitalized for COVID-19, requiring intensive care unit (ICU) admission for COVID-19, and COVID-19-related mortality (including inpatient and outpatient). Medical comorbidities were defined from the International Classification of Diseases, Ninth Revision, and International Classification of Diseases, Tenth Revision, codes and were aggregated into a comorbidity score. Associations with COVID-19 outcomes were examined using odds ratios (ORs)., Results: Of 5698 patients tested for COVID-19 (mean [SD] age, 47.4 [20.9] years; 2167 [38.0%] men; mean [SD] BMI, 30.0 [8.0]), most were non-Hispanic White (3740 patients [65.6%]) or non-Hispanic Black (1058 patients [18.6%]). The comparison group included 7168 individuals who were not tested (mean [SD] age, 43.1 [24.1] years; 3257 [45.4%] men; mean [SD] BMI, 28.5 [7.1]). Among 1139 patients diagnosed with COVID-19, 492 (43.2%) were White and 442 (38.8%) were Black; 523 (45.9%) were hospitalized, 283 (24.7%) were admitted to the ICU, and 88 (7.7%) died. Adjusting for age, sex, socioeconomic status, and comorbidity score, Black patients were more likely to be hospitalized compared with White patients (OR, 1.72 [95% CI, 1.15-2.58]; P = .009). In addition to older age, male sex, and obesity, living in densely populated areas was associated with increased risk of hospitalization (OR, 1.10 [95% CI, 1.01-1.19]; P = .02). In the overall population, higher risk of hospitalization was also observed in patients with preexisting type 2 diabetes (OR, 1.82 [95% CI, 1.25-2.64]; P = .02) and kidney disease (OR, 2.87 [95% CI, 1.87-4.42]; P < .001). Compared with White patients, obesity was associated with higher risk of having test results positive for COVID-19 among Black patients (White: OR, 1.37 [95% CI, 1.01-1.84]; P = .04. Black: OR, 3.11 [95% CI, 1.64-5.90]; P < .001; P for interaction = .02). Having any cancer was associated with higher risk of positive COVID-19 test results for Black patients (OR, 1.82 [95% CI, 1.19-2.78]; P = .005) but not White patients (OR, 1.08 [95% CI, 0.84-1.40]; P = .53; P for interaction = .04). Overall comorbidity burden was associated with higher risk of hospitalization in White patients (OR, 1.30 [95% CI, 1.11-1.53]; P = .001) but not in Black patients (OR, 0.99 [95% CI, 0.83-1.17]; P = .88; P for interaction = .02), as was type 2 diabetes (White: OR, 2.59 [95% CI, 1.49-4.48]; P < .001; Black: OR, 1.17 [95% CI, 0.66-2.06]; P = .59; P for interaction = .046). No statistically significant racial differences were found in ICU admission and mortality based on adjusted analysis., Conclusions and Relevance: These findings suggest that preexisting type 2 diabetes or kidney diseases and living in high-population density areas were associated with higher risk for COVID-19 hospitalization. Associations of risk factors with COVID-19 outcomes differed by race.

The incidence of chronic, non-healing skin wounds is accelerating, largely due to the epidemic of obesity-related Type 2 diabetes. Abnormal inflammation in wounds contributes to delayed healing. During wound repair, blood monocytes are recruited into the wound bed where they differentiate into macrophages that secrete cytokines and regulate subsequent repair events. Because the study of wound macrophages via immunohistochemistry is often unsatisfactory due to nonspecific antibody staining, the ability to isolate and analyze single cells is important for determining the phenotypes of the wound macrophages. In this article, we have expanded upon a protocol originally described by Wilson et al, 2002 [1], and optimized it for isolation of large numbers of viable macrophages from murine skin wounds that are suitable for flow cytometric cell sorting or analysis. Several parameters were found to be critical for improved macrophage yields, including: (1) The proper amount of starting material (skin tissue); (2) The optimal time for addition of Brefeldin A during enzymatic digestion; (3) Revamped guidelines for centrifugation to maximize cell pellet recovery. This optimized protocol could be further modified to perform cell sorting and flow-based immunophenotyping of any cell type involved in wound healing and inflammation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 The Authors. Published by Elsevier B.V.)

Background: Adverse childhood experiences (ACEs) have lifelong health consequences, yet screening remains challenging. Particularly in clinical settings, brief screeners that could lead to comprehensive assessments may be more feasible. We explore how two ACEs (economic hardship, parental/caregiver divorce/separation) are associated with other ACEs, asthma, and emotional, developmental, or behavioral (EDB) problems., Methods: Using the 2016 National Survey of Children's Health, we assessed the associations between ACEs and asthma and EDB problems and calculated sensitivities, specificities and predictive values., Results: Parents frequently reported 1+ ACEs for their child (50.3%). Individual ACE frequency ranged from 4.2 to 29.6%; all were significantly associated with EDB problems (adjusted odds ratios (aORs): 2.2-5.1) and more ACEs confirmed higher odds. Two ACES (economic hardship, parental/caregiver divorce/separation) co-occurred frequently with other ACEs, having either predicted EDB problems similarly to other ACEs (aORs 1.8; 95% CI 1.4, 2.3) and having both greatly increased odds (aOR 3.8; 95% CI 2.8, 5.2). The negative predictive value of EDB problems associated with citing neither ACE was high (95.7%). Similar trends with asthma were observed., Conclusions: Economic hardship and caregiver separation are strongly associated with other ACEs, EDB problems and asthma. A brief screener including these ACEs may reduce clinical barriers to broader ACEs screening.

Background: Acute diarrhoeal disease management often requires rehydration alone without antibiotics. However, non-indicated antibiotics are frequently ordered and this is an important driver of antimicrobial resistance. The mHealth Diarrhoea Management (mHDM) trial aimed to establish whether electronic decision support improves rehydration and antibiotic guideline adherence in resource-limited settings., Methods: A cluster randomised controlled trial was done at ten district hospitals in Bangladesh. Inclusion criteria were patients aged 2 months or older with uncomplicated acute diarrhoea. Admission orders were observed without intervention in the pre-intervention period, followed by randomisation to electronic (rehydration calculator) or paper formatted WHO guidelines for the intervention period. The primary outcome was rate of intravenous fluid ordered as a binary variable. Generalised linear mixed-effect models, accounting for hospital clustering, served as the analytical framework; the analysis was intention to treat. The trial is registered with ClinicalTrials.gov (NCT03154229) and is completed., Findings: From March 11 to Sept 10, 2018, 4975 patients (75·6%) of 6577 screened patients were enrolled. The intervention effect for the primary outcome showed no significant differences in rates of intravenous fluids ordered as a function of decision-support type. Intravenous fluid orders decreased by 0·9 percentage points for paper electronic decision support and 4·2 percentage points for electronic decision support, with a 4·2-point difference between decision-support types in the intervention period (paper 98·7% [95% CI 91·8-99·8] vs electronic 94·5% [72·2-99·1]; p interaction =0·31). Adverse events such as complications and mortality events were uncommon and could not be statistically estimated., Interpretation: Although intravenous fluid orders did not change, electronic decision support was associated with increases in the volume of intravenous fluid ordered and decreases in antibiotics ordered, which are consistent with WHO guidelines., Funding: US National Institutes of Health., (Copyright © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0. license. Published by Elsevier Ltd.. All rights reserved.)

Background: Delivery by cesarean section (C-section) is associated with adverse short-term and long-term infant outcomes. Given that antibiotics during early life are prescribed for infant outcomes that are more likely among c-section deliveries, we hypothesized that postnatal antibiotic exposure will be greater among c-section infants compared to vaginally delivered infants., Objective: The aim of this paper was to evaluate if mode of infant delivery was associated with patterns of systemic antibiotic exposure in children during their first three years., Methods: Pediatric electronic health records from UFHealth, 2011 to 2017 were reviewed. We included singleton, term infants (37-42 weeks gestation) with a birth weight ≥ 2500 grams, with documented mode of delivery and well visits on record. Infants with a neonatal intensive care unit stay were excluded. Both oral and intravenous antibiotics for a 10-day duration were classified as a single episode. The primary outcome was antibiotic episodes in the first three years of life, and a sub-analysis was performed to compare broad-spectrum versus narrow-spectrum antibiotic exposures., Results: The mean number of antibiotic episodes in 4,024 full-term infants was 0.34 (SD = 0.79) and 24.1% of infants had at least one antibiotic episode. Penicillins were the most prescribed antibiotic in children 0-1 years (66.9%) and cephalosporins were the most common antibiotic prescribed for children 1-3 years (56.2%). We did not detect a meaningful or significant rate ratio (RR) between mode of delivery and overall antibiotic episodes 1.14 (95% CI 0.99, 1.31), broad-spectrum episodes 1.19 (95% CI 0.93, 1.52, or narrow-spectrum episodes 1.14 (95% CI 0.97, 1.34)., Conclusion: Our results do not support the hypothesis that postnatal antibiotic exposure was greater among infants delivered by cesarean section compare to infants delivered vaginally during the first three years of life., Competing Interests: The authors have declared that no competing interests exist.

Background: Laboratory-based respiratory polymerase chain reaction (PCR) panels are rarely used in outpatient pediatric practice due to prolonged turn-around times and cost of medical equipment. The BioFire FilmArray Respiratory Panel EZ (RP EZ) is a Clinical Laboratory Improvement Amendments-waived respiratory pathogen PCR panel which rapidly tests for 14 common respiratory organisms. The aim of this study was to identify the distribution of organisms seen in pediatric clinics and to determine if utilization of this point-of-care test improved disease management, while exploring impact on clinic workflow., Methods: From January 2018 through January 2019, when clinically appropriate, patients were tested by the RP EZ and/or antigen tests (Clinic A) or antigen test only (Clinic B). Residual samples from Clinic B antigen tests were frozen and later tested on the RP EZ for definitive pathogen identification. Patient data and prescription records were extracted from the electronic health record., Results: A total of 430 patients had RP EZ tests performed, and at least 1 organism was detected in 70.4% of patients. The most common organisms identified were human rhinovirus/enterovirus, influenza, and respiratory syncytial virus. Appropriate treatment occurred for 93.6% of patients when the RP EZ was performed (Clinic A) versus 87.9% of patients who had only antigen tests performed (Clinic B, P = 0.0445). Utilization of RP EZ testing also significantly reduced appointment duration time (48.0 versus 54.9 minutes, P = 0.0009). Three false-positive influenza B results were identified by antigen testing., Conclusions: A point-of-care PCR panel improved patient care by providing an accurate diagnosis and shortened appointment duration.

Well-regulated differentiation of fibroblasts into myofibroblasts (MF) is critical for skin wound healing. Neoexpression of α-smooth muscle actin (α-SMA), an established marker for MF differentiation, is driven by TGFβ receptor (TGFβR)-mediated signaling. Hyaluronan (HA) and its receptor CD44 may also participate in this process. To further understand this process, primary mouse skin fibroblasts were isolated and treated in vitro with recombinant TGF-β1 (rTGF-β1) to induce α-SMA expression. CD44 expression was also increased. Paradoxically, CD44 knockdown by RNA interference (RNAi) led to increased α-SMA expression and α-SMA-containing stress fibers. Removal of extracellular HA or inhibition of HA synthesis had no effect on α-SMA levels, suggesting a dispensable role for HA. Exploration of mechanisms linking CD44 knockdown to α-SMA induction, using RNAi and chemical inhibitors, revealed a requirement for noncanonical TGFβR signaling through p38MAPK. Decreased monomeric G-actin but increased filamentous F-actin following CD44 RNAi suggested a possible role for myocardin-related transcription factor (MRTF), a known regulator of α-SMA transcription and itself regulated by G-actin binding. CD44 RNAi promoted nuclear accumulation of MRTF and the binding to its transcriptional cofactor SRF. MRTF knockdown abrogated the increased α-SMA expression caused by CD44 RNAi, suggesting that MRTF is required for CD44-mediated regulation of α-SMA. Finally, chemical inhibition of p38MAPK reversed nuclear MRTF accumulation after rTGF-β1 addition or CD44 RNAi, revealing a central involvement of p38MAPK in both cases. We concluded that CD44 regulates α-SMA gene expression through cooperation between two intersecting signaling pathways, one mediated by G-actin/MRTF and the other via TGFβR/p38MAPK., (© 2019 Wang et al.)

We investigate the clinical history, past medical history, and risk status in women with benign intraductal papillomas(IDP). We observed an upgrade rate of 3.9% to ductal carcinoma in situ (DCIS) and upgrade rate of 10.7% to a high-risk lesion. Prior or concurrent atypia or cancer and high-risk status had a significant increase risk of upgrade. Surgical excision of papillomas is recommended especially in high-risk patients and women with concurrent or history of atypia or malignancy., (© 2019 Wiley Periodicals, Inc.)

Background: Photodynamic therapy (PDT) is a non-scarring alternative for treating basal cell carcinoma (BCC) in patients with Basal Cell Nevus Syndrome (BCNS), also known as Gorlin syndrome. In Europe, red light (635 nm) is the predominant source for PDT, whereas in the United States blue light (400 nm) is more widely available. The objective of this study was to conduct a head-to-head comparison of blue light and red light PDT in the same BCNS patients., Methods: In a pilot study of three patients with 141 BCC lesions, 5-aminolevulinate (20% solution) was applied to all tumors. After 4 h, half of the tumors were illuminated with blue light and the remainder with red light. To ensure safety while treating this many tumors simultaneously, light doses were escalated gradually. Six treatments were administered in three biweekly sessions over 4 months, with a final evaluation at 6 months. Tumor status was documented with high-resolution photographs. Persistent lesions were biopsied at 6 months., Results: Clearance rates after blue light (98%) were slightly better than after red light (93%), with blue light shown to be statistically non-inferior to red light. Eight suspicious lesions were biopsied, 5 after red light (5/5 were BCC) and 3 after blue light (1 was BCC). Blue light PDT was reportedly less painful., Conclusion: Blue light and red light PDT appear to be equally safe and perhaps equally effective for treating BCC tumors in BCNS patients. Further studies to evaluate long-term clearance after blue light PDT are needed., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Accurate assessment of abundance forms a central challenge in population ecology and wildlife management. Many statistical techniques have been developed to estimate population sizes because populations change over time and space and to correct for the bias resulting from animals that are present in a study area but not observed. The mobility of individuals makes it difficult to design sampling procedures that account for movement into and out of areas with fixed jurisdictional boundaries. Aerial surveys are the gold standard used to obtain data of large mobile species in geographic regions with harsh terrain, but these surveys can be prohibitively expensive and dangerous. Estimating abundance with ground-based census methods have practical advantages, but it can be difficult to simultaneously account for temporary emigration and observer error to avoid biased results. Contemporary research in population ecology increasingly relies on telemetry observations of the states and locations of individuals to gain insight on vital rates, animal movements, and population abundance. Analytical models that use observations of movements to improve estimates of abundance have not been developed. Here we build upon existing multi-state mark-recapture methods using a hierarchical N-mixture model with multiple sources of data, including telemetry data on locations of individuals, to improve estimates of population sizes. We used a state-space approach to model animal movements to approximate the number of marked animals present within the study area at any observation period, thereby accounting for a frequently changing number of marked individuals. We illustrate the approach using data on a population of elk (Cervus elaphus nelsoni) in Northern Colorado, USA. We demonstrate substantial improvement compared to existing abundance estimation methods and corroborate our results from the ground based surveys with estimates from aerial surveys during the same seasons. We develop a hierarchical Bayesian N-mixture model using multiple sources of data on abundance, movement and survival to estimate the population size of a mobile species that uses remote conservation areas. The model improves accuracy of inference relative to previous methods for estimating abundance of open populations., (© 2018 by the Ecological Society of America.)

With trends toward increasing patient involvement in medical decision-making, decreasing clinic times, and the availability of the Internet, patients and their caregivers are increasingly researching cancer diagnoses online. It is essential for physicians to understand patient Internet usage as it relates to their own health education. Internet usage trends have been studied in various areas, but not in thoracic diseases. This prospective cohort study surveyed 337 thoracic surgery patients and their caregivers with both cancer and non-cancer diagnoses to examine their Internet usage trends. Cancer subjects were more likely to research their condition online if they were younger, had a higher income, had a higher education level, and were currently employed. Only age and income level were predictive for non-cancer subjects. Separately, cancer subjects were more likely to trust information found on the Internet if they had a higher education. Subjects were most likely to conduct research on a hospital website than other websites. These data will be helpful to thoracic surgeons who want to appropriately educate patients and their caregivers and direct them to reliable Internet sources. These data also illustrate the importance of developing trustworthy hospital websites with disease-specific information.

Objective: The purpose of this study was to quantify the amount of scatter radiation received at the skin surface overlying the thyroid gland, salivary gland, lens of the eye, sternum, and uterus during a routine screening digital mammographic examination measured in a representative patient population., Subjects and Methods: The subjects were 207 women without symptoms with varied body mass indexes who underwent annual screening mammography while wearing six optically stimulated luminescence dosimeters placed at the bridge of the nose, right submandibular gland, right and left thyroid lobes, mid sternum, and 2 cm caudal to the umbilicus to assess scatter radiation dose to the skin., Results: The average scatter radiation doses at the skin surface during digital screening mammography in the representative population of women were as follows: overlying the right lobe of the thyroid, 0.24 mGy; left lobe of the thyroid, 0.25 mGy; salivary gland, 0.2 mGy; bridge of the nose, 0.025 mGy; sternum, 0.87 mGy; and umbilicus, 0.011 mGy. The scatter radiation doses at the umbilicus and the bridge of the nose were too low to measure with statistical confidence. Scatter radiation dose increased with increasing body mass index and increasing breast compression thickness., Conclusion: Scatter radiation dose at the skin overlying organs of interest is a small fraction of the entrance skin dose to the breast. The low levels of scatter radiation measured do not support delaying clinically indicated mammography during early pregnancy.

Ulcers and chronic wounds are a particularly common problem in diabetics and are associated with hyperglycemia. In this targeted review, we summarize evidence suggesting that defective wound healing in diabetics is causally linked, at least in part, to hyperglycemia-induced changes in the status of hyaluronan (HA) that resides in the pericellular coat (glycocalyx) of endothelial cells of small cutaneous blood vessels. Potential mechanisms through which exposure to high glucose levels causes a loss of the glycocalyx on the endothelium and accelerates the recruitment of leukocytes, creating a proinflammatory environment, are discussed in detail. Hyperglycemia also affects other cells in the immediate perivascular area, including pericytes and smooth muscle cells, through exposure to increased cytokine levels and through glucose elevations in the interstitial fluid. Possible roles of newly recognized, cross-linked forms of HA, and interactions of a major HA receptor (CD44) with cytokine/growth factor receptors during hyperglycemia, are also discussed.

A wound is a type of injury that damages living tissues. In this review, we will be referring mainly to healing responses in the organs including skin and the lungs. Fibrosis is a process of dysregulated extracellular matrix (ECM) production that leads to a dense and functionally abnormal connective tissue compartment (dermis). In tissues such as the skin, the repair of the dermis after wounding requires not only the fibroblasts that produce the ECM molecules, but also the overlying epithelial layer (keratinocytes), the endothelial cells, and smooth muscle cells of the blood vessel and white blood cells such as neutrophils and macrophages, which together orchestrate the cytokine-mediated signaling and paracrine interactions that are required to regulate the proper extent and timing of the repair process. This review will focus on the importance of extracellular molecules in the microenvironment, primarily the proteoglycans and glycosaminoglycan hyaluronan, and their roles in wound healing. First, we will briefly summarize the physiological, cellular, and biochemical elements of wound healing, including the importance of cytokine cross-talk between cell types. Second, we will discuss the role of proteoglycans and hyaluronan in regulating these processes. Finally, approaches that utilize these concepts as potential therapies for fibrosis are discussed.

A balanced turnover of dermal fibroblasts is crucial for structural integrity and normal function of the skin. During recovery from environmental injury (such as UV exposure and physical wounding), apoptosis is an important mechanism regulating fibroblast turnover. We are interested in the role that hyaluronan (HA), an extracellular matrix molecule synthesized by HA synthase enzymes (Has), plays in regulating apoptosis in fibroblasts. We previously reported that Has1 and Has3 double knock-out (Has1/3 null) mice show accelerated wound closure and increased numbers of fibroblasts in the dermis. In the present study, we report that HA levels and Has2 mRNA expression are higher in cultured Has1/3 null primary skin fibroblasts than in wild type (WT) cells. Apoptosis induced by two different environmental stressors, UV exposure and serum starvation (SS), was reduced in the Has1/3 null cells. Hyaluronidase, added to cultures to remove extracellular HA, surprisingly had no effect upon apoptotic susceptibility to UVB or SS. However, cells treated with 4-methylumbelliferone to inhibit HA synthesis were sensitized to apoptosis induced by SS or UVB. When fibroblasts were transfected with Has2-specific siRNA that lowered Has2 mRNA and HA levels by 90%, both Has1/3 null and WT cells became significantly more sensitive to apoptosis. The exogenous addition of high molecular weight HA failed to reverse this effect. We conclude that Has1/3 null skin fibroblasts (which have higher levels of Has2 gene expression) are resistant to stress-induced apoptosis., (© 2014 by The American Society for Biochemistry and Molecular Biology, Inc.)

A general and efficient approach toward new zirconium and hafnium complexes based on 2-aryl-8-arylaminoquinoline ligands was developed. These precursors, when activated with MAO/borate cocatalyst and supported on silica, result in active olefin polymerization catalysts. The ethylene copolymers produced under industrially relevant conditions show very high molecular weights and unique microstructures defined by the multisite nature of the catalyst. A site-diversification mechanism is proposed to explain the presence of at least five individual sites, as deduced from 3D-TREF analysis of ethylene-butene copolymers.

Hyaluronan (HA) is an abundant matrix molecule, the function of which in the skin remains to be fully defined. To explore the roles of HA in cutaneous injury responses, double-knockout mice (abbreviated as Has1/3 null) that lack two HA synthase enzymes (Has1 and Has3), but still express functional Has2, were used in two types of experiments: (i) application of 12-O-tetradecanoylphorbol-13-acetate (TPA) and (ii) full-thickness wounding of the skin. Uninjured Has1/3-null mice were phenotypically normal. However, after TPA, the accumulation of HA that normally occurs in wild-type epidermis was blunted in Has1/3-null epidermis. In excisional wound-healing experiments, wound closure was significantly faster in Has1/3 null than in wild-type mice. Coincident with this abnormal wound healing, a marked decrease in epidermal and dermal HA and a marked increase in neutrophil efflux from cutaneous blood vessels were observed in Has1/3-null skin relative to wild-type skin. Has1/3-null wounds displayed an earlier onset of myofibroblast differentiation. In summary, selective loss of Has1 and Has3 leads to a proinflammatory milieu that favors recruitment of neutrophils and other inflammation-related changes in the dermis.

Chronic, nonhealing wounds and inadequate tissue repair characterized by excessive fibrosis continue to have a considerable negative effect on health and quality of life. Understanding the molecular events required for adequate healing, including the transcriptional control of wound repair, will be important for the development of future therapies. We previously showed that loss of Hoxb13 from murine skin results in enhanced cutaneous wound healing, suggesting that Hoxb13 has a negative effect on wound repair. To test this, we generated skin-specific Hoxb13 transgenic (TG) mice that overexpress Hoxb13 in the basal layer of the epidermis by the human keratin 14 promoter. Using these mice, we evaluated the effects of Hoxb13 overexpression on cutaneous wound healing. Transgenic wounds were characterized by persistence of the fibrin clot and prolonged inflammation. Notably, neutrophils, which had cleared from wild-type wounds, were still pronounced in TG wounds. Marked epidermal hyperplasia was observed at TG wound edges, and dermal vessels were grossly abnormal compared with wild-type mice. Both vascular endothelial growth factor and tumor necrosis factor-alpha were upregulated in Hoxb13 TG skin. Together, our results identify Hoxb13 as a potential important clinical target in wound healing and other pathologies characterized by abnormal or excessive inflammation, angiogenesis, or epidermal proliferation.

Hyaluronic acid (HA), a glycosaminoglycan located between keratinocytes in the epidermis, accumulates dramatically following skin wounding. To study inductive mechanisms, a rat keratinocyte organotypic culture model that faithfully mimics HA metabolism was used. Organotypic cultures were needle-punctured 100 times, incubated for up to 24 hours, and HA analyzed by histochemical and biochemical methods. Within 15 minutes post-injury, HA levels had elevated two-fold, increasing to four-fold by 24 hours. HA elevations far from the site of injury suggested the possible involvement of a soluble HA-inductive factor. Media transfer experiments (from wounded cultures to unwounded cultures) confirmed the existence of a soluble factor. From earlier evidence, we hypothesized that an EGF-like growth factor might be responsible. This was confirmed as follows: (1) EGFR kinase inhibitor (AG1478) completely prevented wounding-induced HA accumulation. (2) Rapid tyrosine-phosphorylation of EGFR correlated well with the onset of increased HA synthesis. (3) A neutralizing antibody that recognizes heparin binding EGF-like growth factor (HB-EGF) blocked wounding-induced HA synthesis by > or =50%. (4) Western analyses showed that release of activated HB-EGF (but neither amphiregulin nor EGF) occured after wounding. In summary, rapid HA accumulation after epidermal wounding occurs through a mechanism requiring cleavage of HB-EGF and activation of EGFR signaling.

Repeated injury to the stratum corneum of mammalian skin (caused by friction, soaps, or organic solvents) elicits hyperkeratosis and epidermal thickening. Functionally, these changes serve to restore the cutaneous barrier and protect the organism. To better understand the molecular and cellular basis of this response, we have engineered an in vitro model of acetone-induced injury using organotypic epidermal cultures. Rat epidermal keratinocytes (REKs), grown on a collagen raft in the absence of any feeder fibroblasts, developed all the hallmarks of a true epidermis including a well-formed cornified layer. To induce barrier injury, REK cultures were treated with intermittent 30-s exposures to acetone then were fixed and paraffin-sectioned. After two exposures, increased proliferation (Ki67 and BrdU staining) was observed in basal and suprabasal layers. After three exposures, proliferation became confined to localized buds in the basal layer and increased terminal differentiation was observed (compact hyperkeratosis of the stratum corneum, elevated levels of K10 and filaggrin, and heightened transglutaminase activity). Thus, barrier disruption causes epidermal hyperplasia and/or enhances differentiation, depending upon the extent and duration of injury. Given that no fibroblasts are present in the model, the ability to mount a hyperplastic response to barrier injury is an inherent property of keratinocytes.

Crosses between two species of the rodent genus Peromyscus produce defects in both growth and development. The defects are pronounced in the hybrid placentas. Peromyscuys maniculatus (strain BW) females mated to P. polionotus (strain PO) males produce placentas half the size of the parental species, as well as growth-retarded embryos. In contrast, PO females mated to BW males result in defective conceptuses that display embryonic and placental overgrowth. These 'parent-of-origin'-dependent phenotypes are consistent with previous studies that demonstrated altered expression of imprinted genes and genetic linkage of the overgrowth phenotypes to imprinted domains. In the present study, we take a broader approach in assessing perturbations in hybrid placental gene expression through the use of Mus musculus cDNA microarrays. In verifying classes of genes identified in microarray screens differentially regulated during hybrid placental development, we focused on those influencing the cell cycle and extracellular matrix (ECM). Our work suggests that cell cycle regulators at the G(1)/S phase check-point are downregulated in the large hybrid placenta, whereas the small hybrid placenta is more variable. The ECM genes are typically downstream targets of cell cycle regulation and their misregulation is consistent with many of the dysmorphic phenotypes. Thus, these data suggest imbalances in proliferation and differentiation in hybrid placentation.

The skin is the largest organ of the body and consists of the underlying dermis and outer epidermis. Proper embryonic development and continual renewal of the adult epidermis are essential to provide an impenetrable barrier against fluid loss and serve as our most important defense against insults from the external environment. During mammalian embryogenesis the epidermis develops from the surface ectoderm, which initially consists of a multipotent single-layer epithelium. Once these epithelial cells receive the appropriate developmental cues, they become committed to stratify, initiate a massive expansion program, and finally embark on a journey of terminal differentiation to produce the morphologically distinct layers of the epidermis. The culmination of this journey is the formation of an impervious cornified envelope via a highly specialized form of programmed cell death, termed "cornification" (reviewed in Candi et al.), which is distinct in many ways from the classic apoptotic pathways. The epidermal developmental program that is first seen in the fetus is recapitulated for the entire life of the organism. The basal layer of adult skin harbors stem cells, which can divide to produce daughter stem cells and transit amplifying (TA) cells that go on to differentiate and cornify (reviewed in Fuchs and Raghavan). In this review we summarize current knowledge about the molecular regulation of proliferation and cornification in the developing mammalian epidermis. We focus on events in the interfollicular epidermis, with special emphasis on transcriptional regulation by p63, Notch, NF-kappaB/IKK, Hox, AP-1, AP-2, and C/EBP factors. We end with a discussion about perturbations in epidermal proliferation and cornification as they pertain to human skin pathologies.

Hox genes act to differentiate and pattern embryonic structures by promoting the proliferation of specific cell types. An exception is Hoxb13, which functions as a proapoptotic and antiproliferative protein during development of the caudal spinal cord and tail vertebrae and has also been implicated in adult cutaneous wound repair. The adult epidermis, which expresses several Hox genes including Hoxb13, is continually renewed in a program of growth arrest, differentiation, and a specialized form of apoptosis (cornification). Yet little is known about the function(s) of these genes in skin. Based on its role during embryogenesis, Hoxb13 is an attractive candidate to be involved in the regulation of epidermal differentiation. Here, we demonstrate that Hoxb13 overexpression in an adult organotypic epidermal model recapitulates actions of Hoxb13 reported in embryonic development. Epidermal cell proliferation is decreased, apoptosis increased, and excessive terminal differentiation observed, as characterized by enhanced transglutaminase activity and excessive cornified envelope formation. Overexpression of Hoxb13 also produces abnormal phenotypes in the epidermal tissue that resemble certain pathological features of dysplastic skin diseases. Our results suggest that Hoxb13 functions to promote epidermal differentiation, a critical process for skin regeneration and for the maintenance of normal barrier function.

Purpose: To investigate the relationship between connective tissue growth factor (CTGF) and fibrosis and angiogenesis in postoperative peritoneal adhesion formation., Methods: Adhesions were performed in 35 rats by creation of a peritoneal patch. Animals were sacrificed at 7 different time-points over 3 weeks. Adhesions and uninjured peritoneum from all animals were assessed by Northern blotting for CTGF and collagen-I mRNA and by immunohistochemistry for CTGF localization, degree of fibrosis and angiogenesis., Results: Persistent adhesions formed in all animals. CTGF and collagen-I mRNA were increased in adhesions compared to uninjured peritoneum (p < 0.05 for both). The temporal expression pattern depicted delayed peak levels of collagen-I mRNA with increasing tendency for both transcripts at the end of the observation period. Fibrosis within adhesions correlated positively with time after surgery (r = 0.85; p < 0.001) and showed typical signs of chronic tissue fibrosis at later time points. Angiogenesis was detected in adhesions but not in uninjured peritoneum (p = 0.001) and coincided with the spatial and temporal expression of CTGF protein in fibroblasts and vascular endothelial cells., Conclusions: The co-expression of CTGF with increasing fibrosis and angiogenesis in postoperative peritoneal adhesions suggests a role for CTGF as critical molecule in fibrous adhesive disease and target for future adhesion prevention., (Copyright (c) 2005 S. Karger AG, Basel.)

In the adult olfactory bulb (OB), particular chemical classes of odorants preferentially activate glomeruli within loosely defined regions, resulting in a coarse and fractured "chemotopic" map. In zebrafish, amino acids and bile acids predominantly stimulate glomeruli in the lateral and medial OB, respectively. We studied the development of these spatial response maps in zebrafish. At 3 d postfertilization (dpf), the OB contained protoglomerular structures that became refined and more numerous during subsequent days. In a transgenic zebrafish line expressing the Ca2+ indicator protein inverse pericam, mainly in mitral cells, odor responses in the OB were first detected at 2.5-3 dpf. Already at this stage, amino acids and bile acids evoked activity predominantly in the lateral and medial OB, respectively. Two-photon Ca2+ imaging using a synthetic indicator was used to reconstruct activity patterns at higher resolution in three dimensions. Responses to amino acids and bile acids were detected predominantly in the lateral and medial OB, respectively, with little overlap. Between 2.5 and 6 dpf, the number of odor-responsive units increased, but the overall spatial organization of activity persisted. Hence, a coarse spatial organization of functional activity maps is established very early during OB development when glomeruli are not yet differentiated. This spatial organization is maintained during development and growth of neuronal circuits and may have important functions for odor processing in larvae, for the differentiation of glomeruli, and for the refinement of activity maps at later developmental stages.

Under conditions of genomic stress, the Mdm locus in human and in mouse is prone to instability manifested as amplification and oncogenesis. The Mdm2 gene is a known oncogene that is amplified in approximately one-third of sarcomas and whose protein product interacts with the tumor suppressor p53. Concimitant with such gene amplification events is the activation and mobilization of endogenous retroelements, typically through the relaxation of epigenetic controlling mechanisms. Processed pseudogenes, which can be formed through endogenous LINE retroelement activity, may indicate increased genomic instability. We have isolated processed pseudogenes for Mdm2 in Mus caroli DNA, likely formed from independent events in different individuals. This is the first identification and characterization of an Mdm2 pseudogene in any organism. Multiple retrotransposition events are suggested by the variable sequence and genomic structure of the identified pseudogenes across all exons and the 3'UTR. The high degree of similarity between the gene and each pseudogene, as well as the lack of evidence for an Mdm2 pseudogene in several other species of Mus, indicate evolutionarily recent retrotransposition events leading to the formation of the Mdm2 pseudogenes in M. caroli. Previous studies on the Mdm2 locus in Mus caroli showed amplification and overexpression of this gene on double minute chromosomes in a Mus musculus x Mus caroli interspecific hybrid. The identification of an Mdm2 retropseudogene within this species further highlights the predisposition to instability for this region of the genome.

The centromere is a cytologically defined entity that possesses a conserved and restricted function in the cell: it is the site of kinetochore assembly and spindle attachment. Despite its conserved function, the centromere is a highly mutable portion of the chromosome, carrying little sequence conservation across taxa. This divergence has made studying the movement of a centromere, either within a single karyotype or between species, a challenging endeavor. Several hypotheses have been proposed to explain the permutability of centromere location within a chromosome. This permutability is termed "centromere repositioning" when described in an evolutionary context and "neocentromerization" when abnormalities within an individual karyotype are considered. Both are characterized by a shift in location of the functional centromere within a chromosome without a concomitant change in linear gene order. Evolutionary studies across lineages clearly indicate that centromere repositioning is not a rare event in karyotypic evolution and must be considered when examining the evolution of chromosome structure and syntenic order. This paper examines the theories proposed to explain centromere repositioning in mammals. These theories are interpreted in light of evidence gained in human studies and in our presented data from the marsupial model species Macropus eugenii, the tammar wallaby.

In contrast to adult cutaneous wound repair, early gestational fetal cutaneous wounds heal by a process of regeneration, resulting in little or no scarring. Previous studies indicate that down-regulation of HoxB13, a member of the highly conserved family of Hox transcription factors, occurs during fetal scarless wound healing. No down-regulation was noted in adult wounds. Here, we evaluate healing of adult cutaneous wounds in Hoxb13 knockout (KO) mice, hypothesizing that loss of Hoxb13 in adult skin should result in enhanced wound healing. Tensiometry was used to measure the tensile strength of incisional wounds over a 60-day time course; overall, Hoxb13 KO wounds are significantly stronger than wild-type (WT). Histological evaluation of incisional wounds shows that 7-day-old Hoxb13 KO wounds are significantly smaller and that 60-day-old Hoxb13 KO wounds exhibit a more normal collagen architecture compared with WT wounds. We also find that excisional wounds close at a faster rate in Hoxb13 KO mice. Biochemical and histochemical analyses show that Hoxb13 KO skin contains significantly elevated levels of hyaluronan. Because higher levels of hyaluronan and enhanced wound healing are characteristics of fetal skin, we conclude that loss of Hoxb13 produces a more "fetal-like" state in adult skin.

Purpose: Connective tissue growth factor stimulates fibroblast proliferation and extracellular matrix deposition in many fibrotic disorders. The aim of our study was to determine the expression pattern of connective tissue growth factor in postoperative intra-abdominal adhesions., Methods: Adhesions were created in 46 Sprague-Dawley rats by complete dissection and resuturing of a peritoneal patch 2 cm in diameter, lateral from the midline incision. Animals were killed at postoperative Days 3, 6, 9, 12, 15, 18, and 21 and the adhesions scored on a scale of 0 to 5. Tissue samples from adhesion areas and from uninvolved peritoneum were evaluated by Northern and Western blotting for temporal connective tissue growth factor mRNA and protein expression, respectively. Immunohistochemical analysis was performed for connective tissue growth factor localization., Results: Adhesions formed in all animals after surgery and were confined to the peritoneal patches. Adhesion formation increased across time, with significant correlation between adhesion scores and postoperative days (r = 0.329, P = 0.026). Connective tissue growth factor mRNA concentrations were significantly elevated in adhesion tissue throughout the three-week period when compared with normal peritoneum (P = 0.012); peak levels occurred between Days 6 and 15. Western blots demonstrated connective tissue growth factor protein expression in adhesions from Days 6 to 21, in contrast to negligible bands in normal peritoneum. Fibroblasts within the adhesive tissue, but not in uninjured peritoneum, stained positive for connective tissue growth factor by immunohistochemistry., Conclusions: We have demonstrated a specific temporal and spatial expression pattern for connective tissue growth factor in intra-abdominal adhesions during a three-week postoperative time course. According to what is known about the functional role of connective tissue growth factor in fibrogenesis, our findings warrant further investigations addressing a causal relationship between this growth factor and fibrous adhesion formation.