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1.
J Sleep Res ; 32(2): e13730, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36193767

RESUMEN

This study aimed to examine the impact of break duration between consecutive shifts, time of break onset, and prior shift duration on total sleep time (TST) between shifts in heavy vehicle drivers (HVDs), and to assess the interaction between break duration and time of break onset. The sleep (actigraphy and sleep diaries) and work shifts (work diaries) of 27 HVDs were monitored during their usual work schedule for up to 9 weeks. Differences in TST between consecutive shifts and days off were assessed. Linear mixed models (followed by pairwise comparisons) assessed whether break duration, prior shift duration, time of break onset, and the interaction between break duration and break onset were related to TST between shifts. Investigators found TST between consecutive shifts (mean [SD] 6.38 [1.38] h) was significantly less than on days off (mean [SD] 7.63 [1.93] h; p < 0.001). Breaks starting between 12:01 and 8:00 a.m. led to shorter sleep (p < 0.05) compared to breaks starting between 4:01 and 8:00 p.m. Break durations up to 7, 9, and 11 h (Australian and European minimum break durations) resulted in a mean (SD) of 4.76 (1.06), 5.66 (0.77), and 6.41 (1.06) h of sleep, respectively. The impact of shift duration prior to the break and the interaction between break duration and time of break were not significant. HVDs' sleep between workdays is influenced independently by break duration and time of break onset. This naturalistic study provides evidence that current break regulations prevent sufficient sleep duration in this industry. Work regulations should evaluate appropriate break durations and break onset times to allow longer sleep opportunities for HVDs.


Asunto(s)
Sueño , Tolerancia al Trabajo Programado , Humanos , Australia , Duración del Sueño , Actigrafía
2.
Anesth Analg ; 134(5): 1028-1034, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35020621

RESUMEN

BACKGROUND: Venous thromboembolism (VTE) is a leading cause of maternal morbidity and mortality in the United States. Subcutanous unfractionated heparin (UFH) has been used for decades for VTE prophylaxis and under many obstetric quality of care initiatives, hospitalized antepartum patients now receive doses as high as 10,000 units every 12 hours. This practice increases the likelihood of UFH administration around the time that epidural labor analgesia is requested or neuraxial analgesia for cesarean delivery is needed. To clarify the effect of UFH on coagulation, we reviewed the care of hospitalized antepartum patients receiving VTE prophylaxis with UFH to determine the incidence of concurrent abnormal activated partial thromboplastin time (aPTT) values and associated risk factors. METHODS: This retrospective cohort study used data from the University of Chicago Pharmacy database to identify hospitalized antepartum patients receiving subcutaneous UFH from June 1, 2016 to July 1, 2019. Our institutional protocol states that all patients hospitalized for antepartum conditions should receive pharmacologic prophylaxis empirically unless contraindicated. For patients receiving UFH, dosing was based on gestational age: 5000 units every 12 hours for first trimester antepartum patients, 7500 units every 12 hours for second trimester patients, and 10,000 units every 12 hours for patients in the third trimester. As per protocol, aPTT values were obtained 2 hours after the third dose of heparin, and platelet counts after 4 days. Data collection included demographics, comorbidities, heparin doses, aPTT values, platelet counts, creatinine if available, and anesthetic type and complications. Logistic regression was performed to determine the association between elevated aPTT >40 seconds and study variables. RESULTS: Of the 321 antepartum patients who received subcutaneous UFH, 33 (10.3%) had an aPTT >40 seconds, 4 of those 33 patients (12.1%) received 5000 units every 12 hours, 14 (42.2%) received 7500 units every 12 hours, and 15 (45.5%) received 10,000 units every 12 hours. The likelihood of a patient having aPTT >40 seconds was 2.8% with 5000 units every 12 hours, 18.9% with 7500 units every 12 hours, and 14.6% with 10,000 units every 12 hours. CONCLUSIONS: Elevated aPTT values are likely with total daily doses of 15,000 or 20,000 units subcutaneous UFH in hospitalized antepartum patients.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Tromboembolia Venosa , Anticoagulantes , Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Estudios de Cohortes , Femenino , Heparina , Humanos , Tiempo de Tromboplastina Parcial , Embarazo , Estudios Retrospectivos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/prevención & control
3.
Inj Prev ; 27(1): 3-9, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33115707

RESUMEN

INTRODUCTION: Understanding how the COVID-19 pandemic has impacted our health and safety is imperative. This study sought to examine the impact of COVID-19's stay-at-home order on daily vehicle miles travelled (VMT) and MVCs in Connecticut. METHODS: Using an interrupted time series design, we analysed daily VMT and MVCs stratified by crash severity and number of vehicles involved from 1 January to 30 April 2017, 2018, 2019 and 2020. MVC data were collected from the Connecticut Crash Data Repository; daily VMT estimates were obtained from StreetLight Insight's database. We used segmented Poisson regression models, controlling for daily temperature and daily precipitation. RESULTS: The mean daily VMT significantly decreased 43% in the post stay-at-home period in 2020. While the mean daily counts of crashes decreased in 2020 after the stay-at-home order was enacted, several types of crash rates increased after accounting for the VMT reductions. Single vehicle crash rates significantly increased 2.29 times, and specifically single vehicle fatal crash rates significantly increased 4.10 times when comparing the pre-stay-at-home and post-stay-at-home periods. DISCUSSION: Despite a decrease in the number of MVCs and VMT, the crash rate of single vehicles increased post stay-at-home order enactment in Connecticut after accounting for reductions in VMT.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Conducción de Automóvil/estadística & datos numéricos , COVID-19/epidemiología , Vehículos a Motor/estadística & datos numéricos , Connecticut/epidemiología , Humanos , Análisis de Series de Tiempo Interrumpido , SARS-CoV-2 , Transportes/estadística & datos numéricos , Viaje/estadística & datos numéricos
4.
Proc Natl Acad Sci U S A ; 113(12): E1738-46, 2016 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-26884166

RESUMEN

The specific function of microglia, the tissue resident macrophages of the brain and spinal cord, has been difficult to ascertain because of a lack of tools to distinguish microglia from other immune cells, thereby limiting specific immunostaining, purification, and manipulation. Because of their unique developmental origins and predicted functions, the distinction of microglia from other myeloid cells is critically important for understanding brain development and disease; better tools would greatly facilitate studies of microglia function in the developing, adult, and injured CNS. Here, we identify transmembrane protein 119 (Tmem119), a cell-surface protein of unknown function, as a highly expressed microglia-specific marker in both mouse and human. We developed monoclonal antibodies to its intracellular and extracellular domains that enable the immunostaining of microglia in histological sections in healthy and diseased brains, as well as isolation of pure nonactivated microglia by FACS. Using our antibodies, we provide, to our knowledge, the first RNAseq profiles of highly pure mouse microglia during development and after an immune challenge. We used these to demonstrate that mouse microglia mature by the second postnatal week and to predict novel microglial functions. Together, we anticipate these resources will be valuable for the future study and understanding of microglia in health and disease.


Asunto(s)
Encéfalo/citología , Proteínas de la Membrana/análisis , Microglía/química , Proteínas del Tejido Nervioso/análisis , Anciano , Animales , Anticuerpos Monoclonales/inmunología , Biomarcadores , Encéfalo/embriología , Encéfalo/crecimiento & desarrollo , División Celular , Linaje de la Célula , Niño , Endotoxemia/patología , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Humanos , Lipopolisacáridos/toxicidad , Macrófagos/química , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Noqueados , Microglía/fisiología , Persona de Mediana Edad , Compresión Nerviosa , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Traumatismos del Nervio Óptico/patología , Especificidad de Órganos , Conejos , Nervio Ciático/lesiones , Nervio Ciático/patología , Análisis de Secuencia de ARN , Lóbulo Temporal/metabolismo , Transcriptoma
5.
AIDS Care ; 30(11): 1421-1425, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29667424

RESUMEN

Gender identity plays a potentially important role contributing to HIV risk among MSM in South Africa. Where studies have included a focus on gender identity, MSM reporting gender non-conformity have been found to have a higher risk of being HIV positive than other MSM. This article examines HIV risk among gender non-conforming MSM in a sample of 316 MSM in Cape Town, South Africa. Reporting gender non-conformity was associated with higher HIV prevalence and increased HIV risk behaviour. Gender non-conformity was also associated with a higher likelihood of being unemployed and reporting low household incomes. These findings highlight the importance of gender-identity as a factor affecting access to HIV treatment, care, and prevention in South Africa and this is an issue that needs to be addressed in interventions targeting MSM populations.


Asunto(s)
Identidad de Género , Infecciones por VIH/epidemiología , Homosexualidad Masculina , Adolescente , Adulto , Femenino , Infecciones por VIH/prevención & control , Infecciones por VIH/terapia , Accesibilidad a los Servicios de Salud , Humanos , Masculino , Prevalencia , Factores de Riesgo , Sudáfrica/epidemiología , Encuestas y Cuestionarios , Personas Transgénero , Adulto Joven
6.
Am J Physiol Regul Integr Comp Physiol ; 311(3): R451-6, 2016 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27335281

RESUMEN

Changes in osmolality or extracellular NaCl concentrations are detected by specialized neurons in the hypothalamus to increase vasopressin (VP) and stimulate thirst. Recent in vitro evidence suggests this process is mediated by an NH2-terminal variant of the transient receptor potential vanilloid type 1 (TRPV1) channel expressed by osmosensitive neurons of the lamina terminalis and vasopressinergic neurons of the supraoptic nucleus. The present study tested this hypothesis in vivo by analysis of plasma VP levels during acute hypernatremia in awake control and TRPV1(-/-) rats. TRPV1(-/-) rats were produced by a Zinc-finger-nuclease 2-bp deletion in exon 13. Intravenous injection of the TRPV1 agonist capsaicin produced hypotension and bradycardia in control rats, but this response was absent in TRPV1(-/-) rats. Infusion of 2 M NaCl (1 ml/h iv) increased plasma osmolality, electrolytes, and VP levels in both control and TRPV1(-/-) rats. However, plasma VP levels did not differ between strains at any time. Furthermore, a linear regression between plasma VP versus osmolality revealed a significant correlation in both control and TRPV1(-/-) rats, but the slope of the regression lines was not attenuated in TRPV1(-/-) versus control rats. Hypotension produced by intravenous injection of minoxidil decreased blood pressure and increased plasma VP levels similarly in both groups. Finally, both treatments stimulated thirst; however, cumulative water intakes in response to hypernatremia or hypotension were not different between control and TRPV1(-/-) rats. These findings suggest that TRPV1 channels are not necessary for VP secretion and thirst stimulated by hypernatremia.


Asunto(s)
Ingestión de Líquidos , Hipernatremia/metabolismo , Canales Catiónicos TRPV/metabolismo , Sed , Vasopresinas/sangre , Equilibrio Hidroelectrolítico , Animales , Masculino , Ratones Noqueados , Concentración Osmolar , Ratas , Ratas Sprague-Dawley , Canales Catiónicos TRPV/genética , Vasopresinas/metabolismo
7.
Cult Health Sex ; 17(8): 977-89, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25752360

RESUMEN

Research reveals how homophobia and stigma link closely to HIV among men who have sex with men in sub-Saharan Africa. This paper considers the varying impact of homophobic stigma on HIV prevention programmes among men who have sex with men in South Africa. It explores how a community-based HIV prevention programme based in the peri-urban townships of Cape Town was 'translated' to peri-urban Johannesburg. Drawing on interviews with volunteers and programme facilitators in Johannesburg, it argues that an altered homophobic environment to that found in Cape Town gave different opportunities to engage both with other men who have sex with men and the broader community. It also argues that programme facilitators should be mindful of how varying degrees of homophobic stigma may relate to broader theoretical debates about sexual binary relationships, which can help us understand why particular programmes choose to focus on certain activities rather than others.


Asunto(s)
Infecciones por VIH/prevención & control , Educación en Salud/métodos , Homosexualidad Masculina/estadística & datos numéricos , Prevención Primaria/métodos , Adulto , Centros Comunitarios de Salud , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Investigación Cualitativa , Sudáfrica , Adulto Joven
8.
AIDS Care ; 26(7): 882-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24295155

RESUMEN

While research now highlights that men who have sex with men (MSM) in places such as South Africa are at particular risk of HIV infection, left relatively unexplored are potential relationships between one of the most pressing social issues affecting peri-urban MSM - namely homophobic stigma - and sexual risk-taking behaviour. Drawing on research from the Ukwazana baseline study of 316 township MSM in Cape Town we examine how homophobic stigma relates to psychosocial factors such as depression and self-efficacy and the risk activity of unprotected anal intercourse (UAI). By deploying cross-sectional association models, we examine a series of relationships between these variables and offer evidence to suggest that HIV prevention programmes aimed at sexual minority groups should be mindful of potentially complex relationships between social stigmas such as homophobia and sexual risk-taking behaviour.


Asunto(s)
Trastorno Depresivo/psicología , Homofobia/psicología , Homosexualidad Masculina/psicología , Autoeficacia , Sexo Inseguro/psicología , Población Urbana/estadística & datos numéricos , Adulto , Estudios Transversales , Trastorno Depresivo/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Homofobia/estadística & datos numéricos , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Factores de Riesgo , Asunción de Riesgos , Sudáfrica/epidemiología , Encuestas y Cuestionarios , Sexo Inseguro/estadística & datos numéricos
9.
South Med J ; 107(10): 633-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25279867

RESUMEN

OBJECTIVES: It is unknown which measure of adiposity (body mass index [BMI] or waist circumference [WC]) is associated with subclinical atherosclerosis in retired National Football League (NFL) players and whether this relation is attenuated after adjusting for components of the metabolic syndrome (elevated triglycerides, fasting glucose, and low levels of high-density lipoprotein-cholesterol [HDL-C]) that frequently coexist with obesity. METHODS: Coronary artery calcium (CAC) was measured in 926 retired NFL players. BMI was calculated as weight (in kilograms)/height (in meters)(2) and WC was measured in inches. Logistic regression analyses adjusting for age, race, systolic blood pressure, high sensitivity C-reactive protein, triglycerides, HDL-C, and fasting blood glucose were performed to evaluate whether BMI or WC was independently associated with the presence of CAC (CAC score >0). RESULTS: The median age, BMI and WC were 54 years, 31 kg/m(2), and 40 inches, respectively. CAC was present in 61% (n = 562) of retired players. Adjusting for age, race, systolic blood pressure, high sensitivity C-reactive protein, triglycerides, HDL-C, and fasting blood glucose, each standard deviation increase in BMI (4.85 kg/m(2)) was significantly associated with CAC (odds ratio [OR] 1.25, 95% confidence interval [CI] 1.03-1.50), but each standard deviation increase in WC (10.53 inches) was not significantly associated with CAC (OR 1.18, 95% CI 0.96-1.45). There was a significant association for the presence of CAC for highest versus lowest quartiles of both BMI (OR 1.93, 95% CI 1.13-3.28) and WC (OR 1.75, 95% CI 1.05-2.92), although the trend for the presence of CAC was significant only across increasing BMI quartiles, even in models that included WC. CONCLUSIONS: In retired NFL players both BMI and WC were associated with CAC. Higher BMI may be associated with an increasing trend for the presence of CAC independent of WC.


Asunto(s)
Aterosclerosis/etiología , Índice de Masa Corporal , Fútbol Americano , Jubilación , Circunferencia de la Cintura , Aterosclerosis/diagnóstico , Aterosclerosis/metabolismo , Biomarcadores/metabolismo , Calcio/metabolismo , Estudios de Cohortes , Vasos Coronarios/metabolismo , Humanos , Modelos Logísticos , Masculino , Síndrome Metabólico/complicaciones , Persona de Mediana Edad , Factores de Riesgo
10.
11.
Nat Commun ; 15(1): 1442, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365882

RESUMEN

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi's sarcoma (KS) and multiple types of B cell malignancies. Emerging evidence demonstrates that KSHV reprograms host-cell central carbon metabolic pathways, which contributes to viral persistence and tumorigenesis. However, the mechanisms underlying KSHV-mediated metabolic reprogramming remain poorly understood. Carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, and dihydroorotase (CAD) is a key enzyme of the de novo pyrimidine synthesis, and was recently identified to deamidate the NF-κB subunit RelA to promote aerobic glycolysis and cell proliferation. Here we report that KSHV infection exploits CAD for nucleotide synthesis and glycolysis. Mechanistically, KSHV vCyclin binds to and hijacks cyclin-dependent kinase CDK6 to phosphorylate Ser-1900 on CAD, thereby activating CAD-mediated pyrimidine synthesis and RelA-deamidation-mediated glycolytic reprogramming. Correspondingly, genetic depletion or pharmacological inhibition of CDK6 and CAD potently impeded KSHV lytic replication and thwarted tumorigenesis of primary effusion lymphoma (PEL) cells in vitro and in vivo. Altogether, our work defines a viral metabolic reprogramming mechanism underpinning KSHV oncogenesis, which may spur the development of new strategies to treat KSHV-associated malignancies and other diseases.


Asunto(s)
Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Herpesvirus Humano 8/metabolismo , Glucólisis , Carcinogénesis , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Nucleótidos/metabolismo
12.
Burns ; 50(4): 841-849, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38472006

RESUMEN

BACKGROUND: Frailty and comorbidities are important outcome determinants in older patients (age ≥65) with burns. A Geriatric Burn Bundle (Geri-B) was implemented in 2019 at a regional burn center to standardize care for older adults. Components included frailty screening and protocolized geriatric co-management, malnutrition screening with nutritional support, and geriatric-centered pain regimens. METHODS: This study aimed to qualitatively evaluate the implementation of Geri-B using the Proctor Framework. From June-August 2022, older burn-injured patients, burn nurses, and medical staff providers (attending physicians and advanced practice providers) were surveyed and interviewed. Transcribed interviews were coded and thematically analyzed. From May 2022 to August 2023, the number of inpatient visits aged 65 + with a documented frailty screening was monitored. RESULTS: The study included 23 participants (10 providers, 13 patients). Participants highly rated Geri-B in all implementation domains. Most providers rated geriatric care effectiveness as 'good' or 'excellent' after Geri-B implementation. Providers viewed it as a reminder to tailor geriatric care and a safeguard against substandard geriatric care. Staffing shortages, insufficient protocol training, and learning resources were reported as implementation barriers. Many providers advocated for better bundle integration into the hospital electronic health record (EHR) (e.g., frailty screening tool, automatic admission order sets). Most patients felt comfortable being asked about their functional status with strong patient support for therapy services. The average frailty screening completion rate from May 2022 to August 2023 was 86%. CONCLUSIONS: Geri-B was perceived as valuable for the care of older burn patients and may serve as a framework for other burn centers.


Asunto(s)
Quemaduras , Fragilidad , Evaluación Geriátrica , Paquetes de Atención al Paciente , Humanos , Quemaduras/terapia , Anciano , Masculino , Femenino , Evaluación Geriátrica/métodos , Paquetes de Atención al Paciente/métodos , Anciano de 80 o más Años , Unidades de Quemados/organización & administración , Manejo del Dolor/métodos , Desnutrición/terapia , Anciano Frágil , Apoyo Nutricional/métodos
13.
AIDS Behav ; 17 Suppl 1: S33-42, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22903420

RESUMEN

This article considers the complex ways volunteer outreach workers can frame their engagement with a community-based HIV prevention programme for South African township MSM. Drawing on research conducted during the Ukwazana programme in Cape Town it begins by exploring limitations towards MSM participation with programme facilitators (namely previous feelings of mistrust and community homophobia) and strategies developed to offset these concerns. It then considers how great care must also be taken to appreciate how volunteers from marginalised groups can frame training as a key condition for participation. To understand this it is therefore necessary for facilitators to acknowledge a number of additional concerns. These include community status, a lack of bonding social capital between volunteers and a highly developed from of critical consciousness by volunteers regarding HIV prevention possibilities. This article therefore suggests that effort to initially engage marginalised communities must also be met with effort to understand the complex ways volunteers relate to other MSM and to each other.


Asunto(s)
Relaciones Comunidad-Institución , Infecciones por VIH/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Homosexualidad Masculina , Voluntarios/educación , Investigación Participativa Basada en la Comunidad , Comprensión , Estado de Conciencia , Homofobia , Humanos , Relaciones Interpersonales , Entrevistas como Asunto , Masculino , Evaluación de Necesidades , Desarrollo de Programa , Distancia Psicológica , Apoyo Social , Factores Socioeconómicos , Sudáfrica
14.
AIDS Care ; 25(10): 1227-35, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23387517

RESUMEN

Men who have sex with men (MSM) in South Africa remain at particular risk of HIV infection. The Ukwazana baseline survey is the first to explore this risk in relation to psychological factors associated with unprotected anal intercourse (UAI). A cohort of 316 MSM from township peri-urban Cape Town took part in the survey. The survey found that 55.2% had engaged in UAI over the preceding 6 months. Depression was significantly associated with UAI. Respondents with self-efficacy scores less than two standard deviations above the mean were also more likely to have engaged in UAI. A Sobel test for mediation highlighted that the depression-UAI association was partially mediated by self-efficacy, indicating that most of the effect of depression on UAI was not covarying with self-efficacy. This study, therefore, highlights that both depression and self-efficacy should be considered factors to be addressed in HIV-prevention programmes aimed at peri-urban MSM.


Asunto(s)
Depresión/psicología , Infecciones por VIH/prevención & control , Homosexualidad Masculina/psicología , Autoeficacia , Sexo Inseguro , Población Urbana , Adolescente , Adulto , Estudios de Cohortes , Depresión/epidemiología , Encuestas Epidemiológicas , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Factores de Riesgo , Asunción de Riesgos , Conducta Sexual/estadística & datos numéricos , Parejas Sexuales , Sudáfrica/epidemiología , Encuestas y Cuestionarios , Sexo Inseguro/estadística & datos numéricos , Población Urbana/estadística & datos numéricos
15.
Front Mol Neurosci ; 16: 1112927, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063370

RESUMEN

Introduction: Nicotine dependence is one of the main causes of preventable diseases in the United States. Nicotine-seeking and avoidance behavioral assays in larval zebrafish could be used for identifying potential new pharmacotherapeutics in an early phase of drug discovery and could facilitate the identification of genes and genomic variations associated with nicotine-seeking and avoidance behavior. Methods: A new three-choice behavioral assay has been developed for the identification of nicotine-seeking and avoiding larval zebrafish. The three choices are represented by three compartments of a gradient maze. Video-recording and subsequent quantitative analysis of the swimming track was carried out using EthovisionXT (Noldus). Results: Three behavioral phenotypes could be identified. Nicotine-seeking larval zebrafish occupied nicotine compartments for longer periods and entered the nicotine-containing compartments most frequently. Nicotine-avoiders spent most of the cumulative time in the water compartment or entered the water compartment most frequently. Non-seekers remained in the center compartment for most of the time. In the gradient maze, about 20-30% of larval zebrafish had a preference for low nicotine concentrations whereas nicotine avoidance was stronger at higher nicotine concentrations. Lower concentrations of nicotine (0.63 µM, 6.3 µM) resulted in higher percentages of nicotine seekers whereas high nicotine concentrations (63 µM, 630 µM) resulted in higher percentages of nicotine avoiders. Pre-treatment of larval zebrafish with nicotine slightly increased the percentage of nicotine avoiders at lower nicotine concentrations. Treatment with varenicline strongly increased the percentage of nicotine avoiders at lower nicotine concentrations. Conclusion: The results show that larval zebrafish have individual preferences for nicotine that could change with drug treatment. The three-choice gradient maze assay for larval zebrafish provides a new testing paradigm for studying the molecular and cellular mechanisms of nicotine action and the discovery of potential new pharmacotherapeutics for the treatment of smoking cessation.

16.
Biol Invasions ; : 1-17, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37362907

RESUMEN

The goal of most invasive species suppression programs is to achieve long-term sustained reductions in population abundance, yet removal programs can be stymied by density-dependent population responses. We tested a harvest removal strategy for invasive Rusty Crayfish (Faxonius rusticus) at two nearshore native fish spawning habitats in northern Lake Michigan. Changes in average Rusty Crayfish densities were evaluated with a before-after reference-impact study design. We removed 3182 Rusty Crayfish, primarily adults (> 20 mm carapace length), at two sites over two harvest seasons, expending 17,825 trap days in effort. Generalized linear modeling results suggested a statistically significant reduction in Rusty Crayfish densities was achieved at one reef, Little Traverse Bay (LTB Crib). Reduced densities were sustained over the egg maturation period for native fish and into the following year after removal ceased. By late summer/early fall, between consecutive suppression efforts in 2018 and 2019, we observed a threefold increase in pre-removal densities. Size-frequency histograms from diver quadrat surveys showed higher abundances of juvenile (< 20 mm carapace length) size classes the following spring and summer at LTB Crib compared to its paired reference site. Stock-recruit curves fit to count data, pooled across all sites, provided further evidence of density-dependence. With a proviso that we only conducted two seasons of consecutive suppression, this study highlights an important aspect of invasive species management and raises questions about the efficacy of adult-only crayfish removal strategies. Supplementary Information: The online version contains supplementary material available at 10.1007/s10530-023-03076-6.

17.
Digit Health ; 9: 20552076231165972, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37009306

RESUMEN

Objective: Development of personalized sleep-wake management tools is critical to improving sleep and functional outcomes for shift workers. The objective of the current study was to test the performance, engagement and usability of a mobile app (SleepSync) for personalized sleep-wake management in shift workers that aid behavioural change and provide practical advice by providing personalized sleep scheduling recommendations and education. Methods: Shift workers (n = 27; 20 healthcare and 7 from other industries) trialled the mobile app for two weeks to determine performance, engagement and usability. Primary outcomes were self-reported total sleep time, ability to fall asleep, sleep quality and perception of overall recovery on days off. Secondary performance outcomes included sleep disturbances (insomnia and sleep hygiene symptoms, and sleep-related impairments) and mood (anxiety, stress and depression) pre- and post-app use. Satisfaction with schedule management, integration into daily routine and influence on behaviour were used to determine engagement, while the usability was assessed for functionality and ease of use of features. Results: Total sleep time (P = .04), ability to fall asleep (P < .001), quality of sleep (P = .001), insomnia (P = .02), sleep hygiene (P = .01), sleep-related impairments (P = .001), anxiety (P = .001), and stress (P = .006) were all improved, with non-significant improvements in recovery on days off (P = .19) and depression (P = .07). All measures of engagement and usability were scored positively by the majority of users. Conclusions: This pilot trial provides preliminary evidence of the positive impact of the SleepSync app in improving sleep and mood outcomes in shift workers, and warrants confirmation in a larger controlled trial.

18.
Med Phys ; 39(4): 2090-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22482630

RESUMEN

PURPOSE: The purpose of this study is to investigate the feasibility of increasing the system spatial resolution and scanning speed of Hologic Selenia Dimensions digital breast tomosynthesis (DBT) scanner by replacing the rotating mammography x-ray tube with a specially designed carbon nanotube (CNT) x-ray source array, which generates all the projection images needed for tomosynthesis reconstruction by electronically activating individual x-ray sources without any mechanical motion. The stationary digital breast tomosynthesis (s-DBT) design aims to (i) increase the system spatial resolution by eliminating image blurring due to x-ray tube motion and (ii) reduce the scanning time. Low spatial resolution and long scanning time are the two main technical limitations of current DBT technology. METHODS: A CNT x-ray source array was designed and evaluated against a set of targeted system performance parameters. Simulations were performed to determine the maximum anode heat load at the desired focal spot size and to design the electron focusing optics. Field emission current from CNT cathode was measured for an extended period of time to determine the stable life time of CNT cathode for an expected clinical operation scenario. The source array was manufactured, tested, and integrated with a Selenia scanner. An electronic control unit was developed to interface the source array with the detection system and to scan and regulate x-ray beams. The performance of the s-DBT system was evaluated using physical phantoms. RESULTS: The spatially distributed CNT x-ray source array comprised 31 individually addressable x-ray sources covering a 30 angular span with 1 pitch and an isotropic focal spot size of 0.6 mm at full width at half-maximum. Stable operation at 28 kV(peak) anode voltage and 38 mA tube current was demonstrated with extended lifetime and good source-to-source consistency. For the standard imaging protocol of 15 views over 14, 100 mAs dose, and 2 × 2 detector binning, the projection resolution along the scanning direction increased from 4.0 cycles/mm [at 10% modulation-transfer-function (MTF)] in DBT to 5.1 cycles/mm in s-DBT at magnification factor of 1.08. The improvement is more pronounced for faster scanning speeds, wider angular coverage, and smaller detector pixel sizes. The scanning speed depends on the detector, the number of views, and the imaging dose. With 240 ms detector readout time, the s-DBT system scanning time is 6.3 s for a 15-view, 100 mAs scan regardless of the angular coverage. The scanning speed can be reduced to less than 4 s when detectors become faster. Initial phantom studies showed good quality reconstructed images. CONCLUSIONS: A prototype s-DBT scanner has been developed and evaluated by retrofitting the Selenia rotating gantry DBT scanner with a spatially distributed CNT x-ray source array. Preliminary results show that it improves system spatial resolution substantially by eliminating image blur due to x-ray focal spot motion. The scanner speed of s-DBT system is independent of angular coverage and can be increased with faster detector without image degration. The accelerated lifetime measurement demonstrated the long term stability of CNT x-ray source array with typical clinical operation lifetime over 3 years.


Asunto(s)
Aumento de la Imagen/instrumentación , Mamografía/instrumentación , Nanotubos de Carbono , Tomografía Computarizada por Rayos X/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Rayos X
19.
Biodivers Data J ; 10: e87106, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761558

RESUMEN

Background: This paper presents a quantitative and detailed description of the Fossil Lithistida Collection in the Natural History Museum, London. This collection started to be built with the first fossil sponges from the Cretaceous of Wiltshire, collected by William Smith in 1816 and 1818 for the first geological map of England. The latest specimen to enter the collection was collected from the Permo-Carboniferous of Norway by Angela Milner, a researcher at the Museum, in 2000. Although they are mostly from the Cretaceous of England, lithistids are represented from the Cambrian to Cenozoic of England. This makes this collection key for studying this group. Lithistid study will help with understanding of biosilicification evolution in sponges to unlock the changing patterns in the silica cycle in the oceans through geological time. New information: A dataset with information about all the Fossil Lithistida Collection is available through the NHM Data Portal and Suppl. material 1. This dataset includes taxonomic identifications, registration numbers of the specimens, geographic and stratigraphic details, information about specimen collectors and donors, type status and publications where the specimens have been referred.

20.
Manag Biol Invasion ; 13(1): 45-67, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35664708

RESUMEN

At least 65 aquatic plant species have been identified as part of a surveillance list of non-native species that pose a threat to biodiversity and ecosystem services in the Laurentian Great Lakes. Early detection of these potentially invasive aquatic plants (IAP) could minimize impacts of novel incursions and facilitate successful eradication. We developed, implemented, and then adaptively refined a probabilistic boat-based sampling design that aimed to maximize the likelihood of detecting novel IAP incursions in large (400+ hectares) Great Lakes coastal areas. Surveys were conducted from 2017 to 2019 at five Great Lakes locations - St Joseph River (MI), Saginaw River (MI), Milwaukee (WI), Cleveland (OH), and the Detroit River (MI). Aquatic plant communities were characterized across the five sites, with a total of 61 aquatic plant species detected. One-fifth of the species detected in our surveys were non-native to the Great Lakes basin. Sample-based species rarefaction curves, constructed from detection data from all surveys combined at each location, show that the estimated sample effort required for high confidence (> 95%) detection of all aquatic plants at a site, including potentially invasive species, varies (< 100 sample units for Detroit River; > 300 sample units for Milwaukee, roughly equivalent to 6 to 18 days sampling effort, respectively). At least 70% of the estimated species pool was detected at each site during initial 3-day surveys. Leveraging information on detection patterns from initial surveys, including depth and species richness strata, improved survey efficiency and completeness at some sites, with detection of at least 80% of the estimated species pool during subsequent surveys. Based on a forest-based classification and regression method, a combination of just five variables explained 70% or more of the variation in observed richness at all sites (depth, fetch, percent littoral, distance to boat ramps and distance to marinas). We discuss how the model outcomes can be used to inform survey design for other Great Lakes coastal areas. The survey design we describe provides a useful template that could be adaptively improved for early detection of IAP in the Great Lakes.

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