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1.
Am J Emerg Med ; 83: 20-24, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38943708

RESUMEN

INTRODUCTION: Ultrasound is used for peripheral intravenous (PIV) cannulation in patients with difficult landmark-guided IV access in the Emergency Department. Distal-to-proximal application of an Esmarch bandage on the target limb has been suggested as a method for increasing vein size and ease of cannulation. METHODS: This study was a single-blinded crossover randomized controlled trial comparing basilic vein size under ultrasound with use of an Esmarch bandage in addition to standard IV tourniquet ("tourniquet + Esmarch") compared to use of a standard IV tourniquet alone. Participant discomfort with the tourniquet + Esmarch was also compared to that with standard IV tourniquet alone. RESULTS: Twenty-two healthy volunteers were used to measure basilic vein size with and without the Esmarch bandage. There was no difference in basilic vein size between the two groups, with a mean diameter of 6.0 ± 1.5 mm in the tourniquet + Esmarch group and 6.0 ± 1.4 mm in the control group, p = 0.89. Discomfort score (from 0 to 10) was different between the groups, with a mean discomfort score of 2.1 in the tourniquet + Esmarch group and 1.1 in the standard IV tourniquet alone group (p < 0.001). CONCLUSIONS: This study showed that the use of an Esmarch bandage does not increase basilic vein size in healthy volunteers but is associated with a mild increase in discomfort.

2.
Plant Dis ; 108(6): 1612-1620, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38127637

RESUMEN

Phytophthora nicotianae causes devastating disease in a range of hosts, including tobacco (N. tabacum L.), tomato, citrus, strawberry, and numerous ornamentals. Black shank, caused by P. nicotianae, is the most economically important disease to tobacco production in Tennessee and North Carolina. Black shank management includes the use of resistant cultivars, crop rotation, and fungicides. Fungicide resistance is a concern for black shank management due to the limited number of active ingredients available and the repeated exposure of pathogen populations to these products. In vitro fungicide sensitivity assays were conducted on 155 P. nicotianae isolates collected in Tennessee and North Carolina in 2021 and 2022 to determine their EC50 values for oxathiapiprolin, mandipropamid, and fluopicolide. The P. nicotianae was isolated predominantly from burley, dark, and flue-cured tobacco showing symptoms of black shank as well as tomato with buckeye rot symptoms. A discriminatory dose was used to determine each isolate's sensitivity to mefenoxam in 2021 and 2022. In 2021, EC50 values were determined for oxathiapiprolin, mandipropamid, and fluopicolide. In 2022, discriminatory doses based on EC75 values were used to determine each isolate's sensitivity to these fungicides. All isolates from the 2 years were sensitive to mefenoxam, mandipropamid, and fluopicolide. One isolate in 2022 was moderately sensitive to oxathiapiprolin, while all other isolates were sensitive.


Asunto(s)
Fungicidas Industriales , Nicotiana , Phytophthora , Enfermedades de las Plantas , North Carolina , Fungicidas Industriales/farmacología , Phytophthora/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Nicotiana/microbiología , Tennessee , Piridinas/farmacología , Amidas/farmacología , Compuestos Heterocíclicos con 3 Anillos/farmacología , Norbornanos , Alanina/análogos & derivados , Hidrocarburos Fluorados , Pirazoles , Ácidos Carboxílicos
3.
J Emerg Med ; 66(2): 109-132, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38262782

RESUMEN

BACKGROUND: Firearm injury poses a significant public health burden in the United States. OBJECTIVES: The purpose of this systematic review was to provide a comprehensive accounting of the medical costs of firearm injuries in the United States. METHODS: A systematic literature review was conducted to identify studies published between January 1, 2000 and July 13, 2022 that reported medical costs of firearm injuries. A search of Embase, PubMed, and the Cochrane Library databases was performed by a medical librarian. The National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to evaluate for risk of bias. Health care-related charges and costs per firearm injury were presented and trends were identified. RESULTS: Sixty-four studies were included in the analysis. Study sample sizes ranged from 18 to 868,483 patients. Reported costs per injury ranged from $261 to $529,609. The median cost reported was $27,820 (interquartile range [IQR] $15,133-$40,124) and median charge reported was $53,832 (IQR $38,890-$98,632). Studies that divided initial hospitalization costs and follow-up medical costs identified that initial hospitalization accounts for about 60% of total costs. CONCLUSIONS: We found a significant volume of literature about the medical costs of firearm injury, which identified a highly heterogeneous cost burden. A significant amount of cost burden occurs after the index hospitalization, which is the only cost reported in most studies. Limitations of this study include reporting bias that favors hospitalized patients as well as a large focus on hospital charges as measurements of cost identified in the literature.


Asunto(s)
Armas de Fuego , Costos de la Atención en Salud , Heridas por Arma de Fuego , Humanos , Estudios Transversales , Hospitalización , Hospitales , Estados Unidos/epidemiología , Heridas por Arma de Fuego/economía , Heridas por Arma de Fuego/epidemiología
4.
Am J Emerg Med ; 60: 96-100, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35930997

RESUMEN

INTRODUCTION: Patients who present in shock have high expected mortality and early resuscitation is crucial to improve their outcomes. The Critical Care Resuscitation Unit (CCRU) is a specialized unit at the University of Maryland Medical Center (UMMC) that prioritizes early resuscitation of critically ill patients. We hypothesized that lactate clearance and reduction of Sequential Organ Failure Assessment (SOFA) score during CCRU stay would be associated with lower in-hospital mortality. METHODS: We performed a retrospective analysis of adult patients who were admitted to the CCRU between 01/01/2018-12/31/2018 and had a diagnosis of severe shock, determined by serum lactate ≥4 mmol/L. We excluded patients who died during CCRU stay. We used multivariable logistic regression to evaluate the association between lactate clearance and reduction in SOFA scores during CCRU stay and in-hospital mortality. RESULTS: Out of 1740 patients admitted to the CCRU in 2018, 172 (10%) had serum lactate ≥4 mmol/L. Twenty-two (13%) patients died during their CCRU stay. Our primary analysis included 129 patients with lactate clearance data and 136 patients with SOFA data. Average patients' age was 54 years, and median length of stay in the CCRU was 6 h 55 min. The average lactate and SOFA score on admission were 7.4 (3.8) mmol/L and 8.3 (4.7), respectively. Average lactate clearance was 1.9 (3.1) and average SOFA score reduction was 0.2 (2.9). In multivariable logistic regressions evaluating SOFA score and lactate separately, SOFA score reduction during CCRU stay was associated with lower in-hospital mortality (OR 0.83, 95% CI: 0.70-0.97) but lactate clearance was not (OR 0.90, 95% CI 0.78-1.03). In forward stepwise multivariable analysis containing both SOFA score and lactate values, SOFA score clearance during CCRU stay was still associated with decreased in-hospital mortality (OR 0.84, 95% CI 0.72-0.98). CONCLUSIONS: Care in the CCRU is more effective at reducing lactate than SOFA scores in patients with severe shock. However, SOFA score reduction in the resuscitation phase during the CCRU stay was associated with decreased odds of in-hospital mortality in this group of patients. Further studies are necessary to confirm our observations.


Asunto(s)
Unidades de Cuidados Intensivos , Puntuaciones en la Disfunción de Órganos , Adulto , Cuidados Críticos , Mortalidad Hospitalaria , Humanos , Ácido Láctico , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
5.
J Cell Sci ; 132(16)2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31331963

RESUMEN

Ras proteins are small GTPases localized to the plasma membrane (PM), which regulate cellular proliferation, apoptosis and differentiation. After a series of post-translational modifications, H-Ras and N-Ras traffic to the PM from the Golgi via the classical exocytic pathway, but the exact mechanism of K-Ras trafficking to the PM from the ER is not fully characterized. ATP5G1 (also known as ATP5MC1) is one of the three proteins that comprise subunit c of the F0 complex of the mitochondrial ATP synthase. In this study, we show that overexpression of the mitochondrial targeting sequence of ATP5G1 perturbs glucose metabolism, inhibits oncogenic K-Ras signaling, and redistributes phosphatidylserine (PtdSer) to mitochondria and other endomembranes, resulting in K-Ras translocation to mitochondria. Also, it depletes phosphatidylinositol 4-phosphate (PI4P) at the Golgi. Glucose supplementation restores PtdSer and K-Ras PM localization and PI4P at the Golgi. We further show that inhibition of the Golgi-localized PI4-kinases (PI4Ks) translocates K-Ras, and PtdSer to mitochondria and endomembranes, respectively. We conclude that PI4P at the Golgi regulates the PM localization of PtdSer and K-Ras.This article has an associated First Person interview with the first author of the paper.


Asunto(s)
Aparato de Golgi/metabolismo , Mitocondrias/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Animales , Cricetinae , Perros , Aparato de Golgi/genética , Células HEK293 , Humanos , Células de Riñón Canino Madin Darby , Mitocondrias/genética , ATPasas de Translocación de Protón Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Fosfatos de Fosfatidilinositol/genética , Transporte de Proteínas/genética , Proteínas Proto-Oncogénicas p21(ras)/genética
6.
MMWR Morb Mortal Wkly Rep ; 70(17): 639-643, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33914720

RESUMEN

Although COVID-19 mRNA vaccines demonstrated high efficacy in clinical trials (1), they were not 100% efficacious. Thus, some infections postvaccination are expected. Limited data are available on effectiveness in skilled nursing facilities (SNFs) and against emerging variants. The Kentucky Department for Public Health (KDPH) and a local health department investigated a COVID-19 outbreak in a SNF that occurred after all residents and health care personnel (HCP) had been offered vaccination. Among 83 residents and 116 HCP, 75 (90.4%) and 61 (52.6%), respectively, received 2 vaccine doses. Twenty-six residents and 20 HCP received positive test results for SARS-CoV-2, the virus that causes COVID-19, including 18 residents and four HCP who had received their second vaccine dose >14 days before the outbreak began. An R.1 lineage variant was detected with whole genome sequencing (WGS). Although the R.1 variant has multiple spike protein mutations, vaccinated residents and HCP were 87% less likely to have symptomatic COVID-19 compared with those who were unvaccinated. Vaccination of SNF populations, including HCP, is critical to reduce the risk for SARS-CoV-2 introduction, transmission, and severe outcomes in SNFs. An ongoing focus on infection prevention and control practices is also essential.


Asunto(s)
Vacunas contra la COVID-19/administración & dosificación , COVID-19/epidemiología , COVID-19/virología , Brotes de Enfermedades , SARS-CoV-2/genética , Instituciones de Cuidados Especializados de Enfermería , Anciano , COVID-19/prevención & control , Humanos , Programas de Inmunización , Kentucky/epidemiología , SARS-CoV-2/aislamiento & purificación
7.
J Intensive Care Med ; 36(7): 808-817, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32578468

RESUMEN

BACKGROUND: Reduced cholesterol levels are associated with increased organ failure and mortality in sepsis. Cholesterol levels may vary by infection type (gram negative vs positive), possibly reflecting differences in cholesterol-mediated bacterial clearance. METHODS: This was a secondary analysis of a combined data set of 2 prospective cohort studies of adult patients meeting Sepsis-3 criteria. Infection types were classified as gram negative, gram positive, or culture negative. We investigated quantitative (levels) and qualitative (dysfunctional high-density lipoprotein [HDL]) cholesterol differences. We used multivariable logistic regression to control for disease severity. RESULTS: Among 171 patients with sepsis, infections were gram negative in 67, gram positive in 46, and culture negative in 47. Both gram-negative and gram-positive infections occurred in 11 patients. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and HDL cholesterol (HDL-C) levels were lower for culture-positive sepsis at enrollment (TC, P < .001; LDL-C, P < .001; HDL-C, P = .011) and persisted after controlling for disease severity. Similarly, cholesterol levels were lower among culture-positive patients at 48 hours (TC, P = .012; LDL-C, P = .029; HDL-C, P = .002). Triglyceride (TG) levels were lower at enrollment (P =.033) but not at 48 hours (P = .212). There were no differences in dysfunctional HDL. Among bacteremic patients, cholesterol levels were lower at enrollment (TC, P = .010; LDL-C, P = .010; HDL-C, P ≤ .001; TG, P = .005) and at 48 hours (LDL-C, P = .027; HDL-C, P < .001; TG, P = .020), except for 48 hour TC (P = .051). In the bacteremia subgroup, enrollment TC and LDL-C were lower for gram-negative versus gram-positive infections (TC, P = .039; LDL-C, P = .023). CONCLUSION: Cholesterol levels are significantly lower among patients with culture-positive sepsis and bacteremia.


Asunto(s)
Bacteriemia , Sepsis , Choque Séptico , Adulto , Colesterol , Humanos , Estudios Prospectivos , Triglicéridos
9.
J Appl Biomech ; 34(5): 414-418, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29809103

RESUMEN

Lower-extremity musculoskeletal injuries are common in sports such as basketball and soccer. Athletes competing in sports of this nature must maneuver in response to the actions of their teammates, opponents, etc. This limits their ability to preplan movements. The purpose of this study was to compare impact accelerations during preplanned versus unplanned lateral cutting. A total of 30 subjects (15 males and 15 females) performed preplanned and unplanned cuts while the authors analyzed impact accelerations using an accelerometer secured to their tibia. For the preplanned condition, subjects were aware of the movement to perform before initiating a trial. For the unplanned condition, subjects initiated their movement and then reacted to the illumination of one of 3 visual stimuli which dictated whether they would cut, land, or land-and-jump. A mixed-model analysis of variance with a between factor of sex (male and female) and a within factor of condition (preplanned and unplanned) was used to analyze the magnitude and variability of the impact accelerations for the cutting trials. Both males and females demonstrated higher impact accelerations (P = .01) and a trend toward greater intertrial variability (P = .07) for the unplanned cutting trials (vs preplanned cuts). Unplanned cutting may place greater demands on the musculoskeletal system.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Toma de Decisiones , Deportes/fisiología , Tibia/fisiología , Aceleración , Adolescente , Adulto , Femenino , Humanos , Masculino
10.
Emerg Radiol ; 23(3): 221-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26873604

RESUMEN

Emergency department (ED) computed tomography (CT) use has increased substantially in recent years, resulting in increased radiation exposure for patients. Few studies have assessed which parties contribute to CT ordering in the ED. The objective of this study was to determine the proportion of CT scans ordered due to explicit requests by various stakeholders in ED patient care. This is a prospective, observational study performed at three university hospital EDs. CT scans ordered during research assistant hours were eligible for inclusion. Attending emergency physicians (EPs) completed standardized data forms to indicate all parties who had explicitly requested that a specific CT be performed. Forms were completed before the CT results were known in order to minimize bias. Data were obtained from 77 EPs regarding 944 CTs. The parties most frequently requesting CTs were attending EPs (82.0 %, 95 % CI 79.4-84.3), resident physicians (28.6 %, 95 % CI 25.8-31.6), consulting physicians (24.4 %, 95 % CI 21.7-27.2), and admitting physicians (3.9 %, 95 % CI 2.9-5.4). In the 168 instances in which the attending EP did not explicitly request the CT, requests most commonly came from consulting physicians (51.2 %, 95 % CI 43.7-58.6), resident physicians in the ED (39.9 %, 95 % CI 32.8-47.4), and admitting physicians (8.9 %, 95 % CI 5.5-14.2). EPs were the sole party requesting CT in 46.2 % of cases while multiple parties were involved in 39.0 %. Patients, families, and radiologists were uncommon sources of such requests. Emergency physicians requested the majority of CTs, though nearly 20 % were actually not desired by them. Admitting, consulting, and resident physicians in the ED were important contributors to CT utilization.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Prospectivos
12.
Psychol Assess ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709629

RESUMEN

Recent changes to diagnostic criteria for serious conduct problems in children and adolescents have included the presence of elevated callous-unemotional traits to define etiologically and clinically important subgroups of youth with a conduct problem diagnosis. The Clinical Assessment of Prosocial Emotions (CAPE) is an intensive assessment of the symptoms of this limited prosocial emotions specifier that uses a structured professional judgment method of scoring, which may make it useful in clinical settings when diagnoses may require more information than that provided by behavior rating scales. The present study adds to the limited tests of the CAPE's reliability and validity, using a sample of clinic-referred children ages 6-17 years of age, who were all administered the CAPE by trained clinicians. The mean age of the sample was 10.13 years (SD = 2.64); 54% of the sample identified as male and 46% identified as female; and 67% of participants identified as White, 29% identified as Black, and 52% identified as another race/ethnicity (i.e., Asian, Hispanic/Latinx, or other). The findings indicated that CAPE scores demonstrated strong interrater reliability. The scores also were associated with measures of conduct problems and aggression, even when controlling for behavior ratings of callous-unemotional traits. Further, when children with conduct problem diagnoses were divided into groups based on the presence of the limited prosocial emotions specifier from the CAPE, the subgroup with the specifier showed more severe conduct problems and aggression. The results support cautious clinical use of the CAPE, its further development and testing, and research into ways to make its use feasible in many clinical settings. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

13.
bioRxiv ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38328115

RESUMEN

KRAS is a small GTPase, ubiquitously expressed in mammalian cells, that functions as a molecular switch to regulate cell proliferation and differentiation. Oncogenic mutations that render KRAS constitutively active occur frequently in human cancers. KRAS must localize to the plasma membrane (PM) for biological activity. KRAS PM binding is mediated by interactions of the KRAS membrane anchor with phosphatidylserine (PtdSer), therefore, depleting PM PtdSer content abrogates KRAS PM binding and oncogenic function. From a genome-wide siRNA screen to search for genes that regulate KRAS PM localization, we identified a set of phosphatidylinositol (PI) 3-phosphatase family members: myotubularin-related (MTMR) proteins 2, 3, 4 and 7. Here we show that knockdown of MTMR 2/3/4/7 expression disrupts KRAS PM interactions. The molecular mechanism involves depletion of PM PI 4-phosphate (PI4P) levels, which in turn disrupts the subcellular localization and operation of oxysterol-binding protein related protein (ORP) 5, a PtdSer lipid transfer protein that maintains PM PtdSer content. Concomitantly, silencing MTMR 2/3/4/7 expression elevates PM levels of PI3P and reduces PM and total cellular levels of PtdSer. In summary we propose that the PI 3-phosphatase activity provided by MTMR proteins is required to generate PM PI for the synthesis of PM PI4P, which in turn, promotes the PM localization of PtdSer and KRAS.

14.
POCUS J ; 8(1): 88-92, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37152335

RESUMEN

Emergency and critical care physicians frequently encounter patients presenting with dyspnea and normal left ventricular systolic function who may benefit from early diastolic evaluation to determine acute patient management. The current American Society of Echocardiography Guidelines approach to diastolic evaluation is often impractical for point of care ultrasound (POCUS) evaluation, and few studies have evaluated the potential use of a simplified approach. This article reviews the literature on the use of a simplified diastolic evaluation to assist in determining acute patient management.

15.
J Vector Ecol ; 49(1): 44-52, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38147300

RESUMEN

In the United States, there has been a steady increase in diagnosed cases of tick-borne diseases in people, most notably Lyme disease. The pathogen that causes Lyme disease, Borrelia burgdorferi, is transmitted by the blacklegged tick (Ixodes scapularis). Several small mammals are considered key reservoirs of this pathogen and are frequently-used hosts by blacklegged ticks. However, limited studies have evaluated between-species host use by ticks. This study compared I. scapularis burdens and tick-associated pathogen presence in wild-caught Clethrionomys gapperi (southern red-backed voles) and Peromyscus spp. (white-footed mice) in forested areas where the habitat of both species overlapped. Rodent trapping data collected over two summers showed a significant difference in the average tick burden between species. Adult Peromyscus spp. had an overall mean of 4.03 ticks per capture, while adult C. gapperi had a mean of 0.47 ticks per capture. There was a significant association between B. burgdorferi infection and host species with more Peromyscus spp. positive samples than C. gapperi (65.8% and 10.2%, respectively). This work confirms significant differences in tick-host use and pathogen presence between sympatric rodent species. It is critical to understand tick-host interactions and tick distributions to develop effective and efficient tick control methods.


Asunto(s)
Ixodes , Enfermedad de Lyme , Humanos , Animales , Adulto , Roedores , Peromyscus , Arvicolinae
18.
Phlebology ; 37(9): 678-685, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36114157

RESUMEN

BACKGROUND: Despite socioeconomic disparities, no association between clinical presentation and poor outcomes explains a higher mortality in African Americans with pulmonary embolism (PE). The objective is to identify the co-morbidities and echocardiographic characteristics associated with increased mortality in African American patients. METHODS: This is a cross-sectional study of Caucasian or African American patients with PE diagnosed between October 2015 and December 2017 at University of Maryland Medical Center. The outcomes were in-hospital death, length of stay, and bleeding. RESULTS: There were 303 African Americans and 343 Caucasians. Caucasians were older (p = 0.007), males (p = 0.01) with history of coronary artery revascularization (CABG (p = 0.001), coronary stents (p = 0.001)), trauma (p = 0.007), and/or recent surgeries (p = 0.0001). African Americans exhibited higher rates of diabetes (p = 0.01), chronic kidney disease (p = 0.0005), and smoking (p = 0.04). Severity of PE was similar between groups and there was no difference in clot burden size. African Americans had more right ventricular strain on Computer Tomography (p = 0.001) and echocardiogram (p = 0.004); also, underfilled left ventricles (p = 0.02) and higher right ventricular systolic pressures (p = 0.001). There was no difference in hospital mortality (7.1% vs. 7.9%, p = 0.71), length of stay (13.1 ± 16.7 vs 12.8 ± 14.9, p = 0.80) and bleeding (9.0% vs.8.3%. p = 0.72). Mortality was higher in African Americans who received advanced therapies (3.8% vs. 18.8%, p = 0.02). The risk of death increased with age (OR 1.04; 95%CI 1.020-1.073) and with advanced therapies (OR 2.43; 95%CI 1.029-5.769). CONCLUSIONS: Differences in co-morbidities, radiologic findings, and echocardiographic characteristics that may contribute to higher mortality in African American patients, specifically those receiving advanced therapies.


Asunto(s)
Negro o Afroamericano , Embolia Pulmonar , Enfermedad Aguda , Estudios Transversales , Ecocardiografía , Mortalidad Hospitalaria , Humanos , Masculino , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/terapia
19.
Sci Rep ; 11(1): 19719, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34611201

RESUMEN

Many pheromone sensing bacteria produce and detect more than one chemically distinct signal, or autoinducer. The pathways that detect these signals are typically noisy and interlocked through crosstalk and feedback. As a result, the sensing response of individual cells is described by statistical distributions that change under different combinations of signal inputs. Here we examine how signal crosstalk reshapes this response. We measure how combinations of two homoserine lactone (HSL) input signals alter the statistical distributions of individual cell responses in the AinS/R- and LuxI/R-controlled branches of the Vibrio fischeri bioluminescence pathway. We find that, while the distributions of pathway activation in individual cells vary in complex fashion with environmental conditions, these changes have a low-dimensional representation. For both the AinS/R and LuxI/R branches, the distribution of individual cell responses to mixtures of the two HSLs is effectively one-dimensional, so that a single tuning parameter can capture the full range of variability in the distributions. Combinations of crosstalking HSL signals extend the range of responses for each branch of the circuit, so that signals in combination allow population-wide distributions that are not available under a single HSL input. Dimension reduction also simplifies the problem of identifying the HSL conditions to which the pathways and their outputs are most sensitive. A comparison of the maximum sensitivity HSL conditions to actual HSL levels measured during culture growth indicates that the AinS/R and LuxI/R branches lack sensitivity to population density except during the very earliest and latest stages of growth respectively.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Percepción de Quorum , Transducción de Señal , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Microbiología Ambiental , Regulación Bacteriana de la Expresión Génica , Genes Reporteros , Microscopía Fluorescente
20.
J Natl Med Assoc ; 112(2): 176-185, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32178886

RESUMEN

OBJECTIVE: In this report, we used a qualitative descriptive design to explore young African American adults' intergenerationally influenced strategies to experienced racial discrimination. METHODS: The study was guided by a qualitative descriptive design using criterion and snowball sampling, and semi-structured interview questions. We also explored, quantitatively, gender differences among the racial discrimination experiences encountered and the strategies used. FINDINGS: Forty-nine participants included in this report were an average age of 29.5 (SD = 10.1). Racial discrimination experiences included daily microaggressions such as insensitive comments, stereotyping, exclusion from work and school activities, perceived low expectations, inequities in employment, and police profiling. Intergenerationally influenced strategies used in response to these experiences included religious beliefs and practices, positive reframing, and modeling behaviors used by previous generations. These intergenerationally influenced strategies enabled participants to remain calm, to express goodwill toward others, and to be patient and hopeful for a better future. CONCLUSION: Since intergenerationally influenced strategies are likely potential sources of strength and resilience for young African Americans, knowledge of these strategies might be useful to health care practitioners seeking to improve the mental health care of this population.


Asunto(s)
Negro o Afroamericano , Trauma Histórico , Relaciones Intergeneracionales/etnología , Servicios de Salud Mental/normas , Racismo , Resiliencia Psicológica , Adulto , Negro o Afroamericano/etnología , Negro o Afroamericano/psicología , Femenino , Trauma Histórico/psicología , Trauma Histórico/rehabilitación , Humanos , Masculino , Evaluación de Necesidades , Mejoramiento de la Calidad/organización & administración , Racismo/etnología , Racismo/psicología , Discriminación Social/prevención & control , Interacción Social/etnología , Espiritualidad , Estados Unidos/epidemiología
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