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1.
Pediatrics ; 151(3)2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36734089

RESUMEN

OBJECTIVE: The American Heart Association and American Academy of Pediatrics endorse the preparticipation physical evaluation (PPE) to screen student athletes for the risk of sudden cardiac arrest. We sought to identify barriers precluding its use and improve utilization. METHODS: We analyzed documentation of PPE elements during well-care visits of patients aged 12 to 18 years from 5 primary care practices. Employing quality improvement (QI) methodology, we focused on improving PPE utilization in 1 practice by assessing the number of PPE elements addressed per chart. We expanded our QI project to 4 additional practices by using the same interventions but assessing the percentage of charts that had a complete PPE documented. RESULTS: A baseline analysis of 5 targeted practices revealed an average of 3.5 of 14 PPE elements documented. Using plan-do-study-act cycles, PPE elements addressed increased from 2.5 to 14 over an 18-month period in the initial practice. By spreading successful interventions to 4 other practices, complete PPE utilization increased from a median baseline of 10.0% to a median of 70.0% over a 12-month period. Postintervention, 12 of 16 patients (75%) required additional follow-up with pediatric cardiology beyond the initial consultation, as compared with 2 of 14 patients (14%) preintervention. CONCLUSION: The PPE is an underutilized but effective tool in screening student athletes for sudden cardiac arrest. QI methodology was helpful in increasing the use of PPE in the primary care setting.


Asunto(s)
Deportes , Humanos , Niño , Atletas , Muerte Súbita Cardíaca/prevención & control , Examen Físico/métodos , Estudiantes
2.
Adv Neonatal Care ; 21(3): 222-231, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33350711

RESUMEN

BACKGROUND: An unsafe sleep environment remains the leading contributor to unexpected infant death. PURPOSE: To determine the effectiveness of a quality improvement initiative developed to create a hospital-based safe sleep environment for all newborns and infants. METHODS: A multidisciplinary team from the well-baby nursery (WBN) and neonatal intensive care unit (NICU) of a 149-bed academic, quaternary care, regional referral center developed and implemented safe sleep environments within the hospital for all prior to discharge. To monitor compliance, the following were tracked monthly: documentation of parent education, caregiver surveys, and hospital crib check audits. On the inpatient general pediatric units, only hospital crib check audits were tracked. Investigators used Plan-Do-Study-Act (PDSA) cycles to evaluate the impact of the initiative from October 2015 through February 2018. RESULTS: Safe sleep education was documented for all randomly checked records (n = 440). A survey (n = 348) revealed that almost all caregivers (95.4%) reported receiving information on safe infant sleep. Initial compliance with all criteria in WBN (n = 281), NICU (n = 285), and general pediatric inpatient units (n = 121) was 0%, 0%, and 8.3%, respectively. At 29 months, WBN and NICU compliance with all criteria was 90% and 100%, respectively. At 7 months, general pediatric inpatient units' compliance with all criteria was 20%. IMPLICATIONS FOR PRACTICE: WBN, NICU and general pediatric inpatient unit collaboration with content experts led to unit-specific strategies that improved safe sleep practices. IMPLICATIONS FOR RESEARCH: Future studies on the impact of such an initiative at other hospitals are needed.


Asunto(s)
Muerte Súbita del Lactante , Niño , Hospitales , Humanos , Lactante , Cuidado del Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Sueño , Muerte Súbita del Lactante/prevención & control
3.
Pediatrics ; 145(4)2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32213648

RESUMEN

BACKGROUND: Pediatricians are less frequently sued than other physicians. When suits are successful, however, the average payout is higher. Little is known about changes in the risk of litigation over time. We sought to characterize malpractice lawsuit trends for pediatricians over time. METHODS: The Periodic Survey is a national random sample survey of American Academy of Pediatrics members. Seven surveys between 1987 and 2015 asked questions regarding malpractice (n = 5731). Bivariate and multivariable analyses examined trends and factors associated with risk and outcome of malpractice claims and lawsuits. Descriptive analyses examined potential change in indemnity amount over time. RESULTS: In 2015, 21% of pediatricians reported ever having been the subject of any claim or lawsuit, down from a peak of 33% in 1990. Report of successful outcomes in the most-recent suit trended upward between 1987 and 2015, greatest in 2015 at 58%. Median indemnity was unchanged, averaging $128 000 in 2018 dollars. In multivariate analysis, male sex, hospital-based subspecialty (neonatology, pediatric critical care, pediatric emergency medicine, and hospital medicine), longer career, and more work hours were associated with a greater risk of malpractice claim. CONCLUSIONS: From 1987 to 2015, the proportion of pediatricians sued has decreased and median indemnity has remained unchanged. Male pediatricians and hospital-based subspecialists were more likely to have been sued. Greater knowledge of the epidemiology of malpractice claims against pediatricians is valuable because it can impact practice arrangements, advise risk-management decisions, influence quality and safety projects, and provide data to guide advocacy for appropriate tort reform and future research.


Asunto(s)
Mala Praxis/tendencias , Pediatría/tendencias , Adulto , Análisis de Varianza , Competencia Clínica/estadística & datos numéricos , Femenino , Humanos , Masculino , Mala Praxis/economía , Mala Praxis/legislación & jurisprudencia , Mala Praxis/estadística & datos numéricos , Persona de Mediana Edad , Pediatras/estadística & datos numéricos , Pediatras/tendencias , Pediatría/economía , Pediatría/estadística & datos numéricos , Ubicación de la Práctica Profesional/estadística & datos numéricos , Riesgo , Sesgo de Selección , Factores Sexuales , Encuestas y Cuestionarios/estadística & datos numéricos , Estados Unidos
4.
J Pediatr Genet ; 8(2): 63-68, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31061748

RESUMEN

Unexplained childhood fracture(s) warrant consideration of physical abuse and osteogenesis imperfecta (OI). Genetic OI testing may identify "variants of unknown significance (VUS)." Interpretation of VUS in context of potential abuse may have protective, criminal, and medical impacts. This case series explores practices regarding clinicians' interpretation of VUS during child abuse evaluations. Variability was noted regarding factors considered for interpreting clinical significance. Based on these cases, recommendations for careful and thorough evaluation are detailed, including proposed use of a limited follow-up skeletal survey in 3 months, as a consideration to assess healing of prior fractures and to look for any additional injuries.

5.
Pediatrics ; 143(3)2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30804075

RESUMEN

Although most health care providers will go through their careers without experiencing a major disaster in their local communities, if one does occur, it can be life and career altering. The American Academy of Pediatrics has been in the forefront of providing education and advocacy on the critical importance of disaster preparedness. From experiences over the past decade, new evidence and analysis have broadened our understanding that the concept of preparedness is also applicable to addressing the unique professional liability risks that can occur when caring for patients and families during a disaster. Concepts explored in this technical report will help to inform pediatric health care providers, advocates, and policy makers about the complexities of how providers are currently protected, with a focus on areas of unappreciated liability. The timeliness of this technical report is emphasized by the fact that during the time of its development (ie, late summer and early fall of 2017), the United States went through an extraordinary period of multiple, successive, and overlapping disasters within a concentrated period of time of both natural and man-made causes. In a companion policy statement (www.pediatrics.org/cgi/doi/10.1542/peds.2018-3892), recommendations are offered on how individuals, institutions, and governments can work together to strengthen the system of liability protections during disasters so that appropriate and timely care can be delivered with minimal fear of legal reprisal or confusion.


Asunto(s)
Planificación en Desastres/métodos , Desastres , Responsabilidad Legal , Pediatría/métodos , Médicos , Planificación en Desastres/legislación & jurisprudencia , Planificación en Desastres/normas , Desastres/prevención & control , Humanos , Pediatría/legislación & jurisprudencia , Pediatría/normas , Médicos/legislación & jurisprudencia , Médicos/normas , Factores de Riesgo , Estados Unidos/epidemiología
6.
Pediatrics ; 143(3)2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30804076

RESUMEN

Although most health care providers will go through their careers without experiencing a major disaster in their local communities, if one does occur, it can be life and career altering. The American Academy of Pediatrics has been at the forefront of providing education and advocacy on the critical importance of disaster preparedness. From experiences over the past decade, new evidence and analysis have broadened our understanding that the concept of preparedness is also applicable to addressing the unique professional liability risks that can occur when caring for patients and families during a disaster. In our recommendations in this policy statement, we target pediatric health care providers, advocates, and policy makers and address how individuals, institutions, and government can work together to strengthen the system of liability protections during disasters so that appropriate and timely care can be delivered with minimal fear of legal reprisal or confusion.


Asunto(s)
Planificación en Desastres/métodos , Desastres , Recursos en Salud , Responsabilidad Legal , Pediatría/métodos , Médicos , Planificación en Desastres/legislación & jurisprudencia , Planificación en Desastres/normas , Desastres/prevención & control , Recursos en Salud/legislación & jurisprudencia , Recursos en Salud/normas , Humanos , Pediatría/legislación & jurisprudencia , Pediatría/normas , Médicos/legislación & jurisprudencia , Médicos/normas , Estados Unidos
7.
Molecules ; 23(8)2018 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-30103547

RESUMEN

There is growing recognition regarding the role of intracellular amyloid beta (Aß) in the Alzheimer's disease process, which has been linked with aberrant signaling and the disruption of protein degradation mechanisms. Most notably, intraneuronal Aß likely underlies the oxidative stress and mitochondrial dysfunction that have been identified as key elements of disease progression. In this study, we employed fluorescence imaging to explore the ability of a bifunctional small molecule to reduce aggregates of intracellular Aß and attenuate oxidative stress. Structurally, this small molecule is comprised of a nitroxide spin label linked to an amyloidophilic fluorene and is known as spin-labeled fluorene (SLF). The effect of the SLF on intracellular Aß accumulation and oxidative stress was measured in MC65 cells, a human neuronal cell line with inducible expression of the amyloid precursor protein and in the N2a neuronal cell line treated with exogenous Aß. Super-resolution microscopy imaging showed SLF decreases the accumulation of intracellular Aß. Confocal microscopy imaging of MC65 cells treated with a reactive oxygen species (ROS)-sensitive dye demonstrated SLF significantly reduces the intracellular Aß-induced ROS signal. In order to determine the contributions of the separate SLF moieties to these protective activities, experiments were also carried out on cells with nitroxides lacking the Aß targeting domain or fluorene derivatives lacking the nitroxide functionality. The findings support a synergistic effect of SLF in counteracting both the conformational toxicity of both endogenous and exogenous Aß, its promotion of ROS, and Aß metabolism. Furthermore, these studies demonstrate an intimate link between ROS production and Aß oligomer formation.


Asunto(s)
Péptidos beta-Amiloides/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/farmacología , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Línea Celular , Fluorenos/química , Fluorenos/farmacología , Expresión Génica , Humanos , Modelos Moleculares , Agregado de Proteínas/efectos de los fármacos , Agregación Patológica de Proteínas/metabolismo , Conformación Proteica , Multimerización de Proteína , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Marcadores de Spin
8.
J Lipid Res ; 57(6): 955-68, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27087439

RESUMEN

Dysfunction of the cerebrovasculature plays an important role in vascular cognitive impairment (VCI). Lipotoxic injury of the systemic endothelium in response to hydrolyzed triglyceride-rich lipoproteins (TGRLs; TGRL lipolysis products) or a high-fat Western diet (WD) suggests similar mechanisms may be present in brain microvascular endothelium. We investigated the hypothesis that TGRL lipolysis products cause lipotoxic injury to brain microvascular endothelium by generating increased mitochondrial superoxide radical generation, upregulation of activating transcription factor 3 (ATF3)-dependent inflammatory pathways, and activation of cellular oxidative stress and apoptotic pathways. Human brain microvascular endothelial cells were treated with human TGRL lipolysis products that induced intracellular lipid droplet formation, mitochondrial superoxide generation, ATF3-dependent transcription of proinflammatory, stress response, and oxidative stress genes, as well as activation of proapoptotic cascades. Male apoE knockout mice were fed a high-fat/high-cholesterol WD for 2 months, and brain microvessels were isolated by laser capture microdissection. ATF3 gene transcription was elevated 8-fold in the hippocampus and cerebellar brain region of the WD-fed animals compared with chow-fed control animals. The microvascular injury phenotypes observed in vitro and in vivo were similar. ATF3 plays an important role in mediating brain microvascular responses to acute and chronic lipotoxic injury and may be an important preventative and therapeutic target for endothelial dysfunction in VCI.


Asunto(s)
Factor de Transcripción Activador 3/genética , Traumatismos Cerebrovasculares/genética , Disfunción Cognitiva/genética , Inflamación/genética , Lipoproteínas/metabolismo , Triglicéridos/metabolismo , Factor de Transcripción Activador 3/biosíntesis , Animales , Cerebelo/irrigación sanguínea , Cerebelo/metabolismo , Cerebelo/patología , Traumatismos Cerebrovasculares/metabolismo , Traumatismos Cerebrovasculares/fisiopatología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/fisiopatología , Dieta Alta en Grasa/efectos adversos , Dieta Occidental/efectos adversos , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Hipocampo/irrigación sanguínea , Hipocampo/metabolismo , Hipocampo/patología , Humanos , Inflamación/metabolismo , Inflamación/fisiopatología , Ratones , Estrés Oxidativo/genética , Transducción de Señal/genética
9.
Biochim Biophys Acta ; 1854(12): 1860-1870, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26374940

RESUMEN

Alzheimer's disease is characterized by the presence of extracellular plaques comprised of amyloid beta (Aß) peptides. Soluble oligomers of the Aß peptide underlie a cascade of neuronal loss and dysfunction associated with Alzheimer's disease. Single particle analyses of Aß oligomers in solution by fluorescence correlation spectroscopy (FCS) were used to provide real-time descriptions of how spin-labeled fluorenes (SLFs; bi-functional small molecules that block the toxicity of Aß) prevent and disrupt oligomeric assemblies of Aß in solution. Furthermore, the circular dichroism (CD) spectrum of untreated Aß shows a continuous, progressive change over a 24-hour period, while the spectrum of Aß treated with SLF remains relatively constant following initial incubation. These findings suggest the conformation of Aß within the oligomer provides a complementary determinant of Aß toxicity in addition to oligomer growth and size. Although SLF does not produce a dominant state of secondary structure in Aß, it does induce a net reduction in beta secondary content compared to untreated samples of Aß. The FCS results, combined with electron paramagnetic resonance spectroscopy and CD spectroscopy, demonstrate SLFs can inhibit the growth of Aß oligomers and disrupt existing oligomers, while retaining Aß as a population of smaller, yet largely disordered oligomers.


Asunto(s)
Péptidos beta-Amiloides/química , Fluorenos/química , Marcadores de Spin , Línea Celular , Dicroismo Circular , Humanos , Estructura Secundaria de Proteína
10.
J Spec Pediatr Nurs ; 20(3): 187-92, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25898856

RESUMEN

PURPOSE: To evaluate whether an educational video would impact infant sleep practices among new mothers. DESIGN AND METHODS: Survey responses of new mothers who did (n = 43) versus did not (n = 49) watch the educational video were compared to identify differences in observed and planned infant sleep practices. RESULTS: Mothers who watched the video were more likely to observe safe sleep practices while in the hospital (67.4% vs. 46.9%, p < .05). They were also less likely to plan for (unsafe) side positioning (23.9% vs. 7.1%, p < .05). PRACTICE IMPLICATIONS: Given the potentially fatal consequence of unsafe sleep, a brief video provided by nursing staff can be a prudent component of new parent education.


Asunto(s)
Promoción de la Salud/métodos , Cuidado del Lactante/métodos , Madres/educación , Sueño , Grabación en Video , Adulto , Femenino , Humanos , Conducta del Lactante , Recién Nacido , Conducta Materna , Evaluación de Procesos y Resultados en Atención de Salud , Adulto Joven
11.
J Forensic Sci ; 60(2): 444-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25677469

RESUMEN

This single-blinded, randomized validation study was conducted to evaluate whether fluorescence under alternate light sources (ALS) is sufficient to diagnose subclinical bruising (bruising not visible under white light). Standardized trauma was induced on randomly selected ventral forearms. On days 1, 7, and 14 investigators independently examined case forearms under white light for perceived bruising and under ALS for fluorescence and compared body maps. 56 case and 62 control forearms (n = 118) were examined. Sensitivity of ALS on days 1, 7, and 14 was 76.8%, 69.6%, and 60.7%, respectively, compared to 69.6%, 60.0%, and 32.1% for white light. The specificity of ALS on days 1, 7, and 14 was 51.6%, 59.7%, and 53.2%, respectively, compared to 71.0%, 81.4%, and 86.9% for white light. ALS has increased sensitivity yet low specificity compared to white light in accurately detecting bruises. Fluorescence under ALS is not sufficient to accurately or responsibly diagnose subclinical bruising.


Asunto(s)
Contusiones/diagnóstico , Fluorescencia , Traumatismos del Antebrazo/diagnóstico , Medicina Legal/instrumentación , Luz , Adulto , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Distribución Aleatoria , Sensibilidad y Especificidad , Método Simple Ciego , Adulto Joven
12.
Eur J Med Chem ; 77: 343-50, 2014 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-24657571

RESUMEN

A series of new Tacrine analogs modified with nitroxides or pre-nitroxides on 9-amino group via methylene or piperazine spacers were synthesized; the nitroxide or its precursors were incorporated into the Tacrine scaffold. The new compounds were tested for their hydroxyl radical and peroxyl radical scavenging ability, acetylcholinesterase inhibitor activity and protection against Aß-induced cytotoxicity. Based on these assays, we conclude that Tacrine analogs connected to five and six-membered nitroxides via piperazine spacers (9b, 9b/HCl and 12) exhibited the best activity, providing direction for further development of additional candidates with dual functionality (anti Alzheimer's and antioxidant).


Asunto(s)
Acetilcolinesterasa/metabolismo , Antineoplásicos/farmacología , Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Óxidos de Nitrógeno/química , Tacrina/análogos & derivados , Tacrina/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antioxidantes/síntesis química , Antioxidantes/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad , Tacrina/síntesis química , Tacrina/química
13.
J Womens Health (Larchmt) ; 23(4): 350-7, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24552357

RESUMEN

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death in women, yet significant health disparities exist for high-risk groups, including Latinas, and comprehensive, culturally relevant, and effective prevention intervention models are lacking. We used a systems approach to develop, assess, and pilot a community-based education program for improving outcomes for knowledge/awareness of CVD, cardiometabolic risk, and health behaviors in Latinas. METHODS: Latinas (n=35, mean age 50) participated in a 4-month community-based bilingual preventive cardiovascular education program. Pre/post analyses were for knowledge/awareness of CVD risk factors, symptoms, calling 911; personal risk factors (smoking, physical inactivity, family history of CVD); clinical parameters (weight, body mass index [BMI], waist, blood pressure, fasting lipids, and glucose); diagnosis of metabolic syndrome (MetS); and serum inflammatory markers (tumor necrosis factor [TNF]-α, high-sensitivity C reactive protein [hsCRP], and interleukin [IL]-12). RESULTS: Baseline knowledge/awareness was relatively low, risk factors and MetS prevalent, and serum inflammatory markers elevated. Postintervention, participants demonstrated significant (p<0.05) improvements in knowledge of symptoms, risk factors for CVD, calling 911, and knowledge/adoption of heart-healthy behaviors. Clinical health status also improved, especially for serum triglycerides (p<0.05; 21% decline), prevalence of MetS (from 43% to 37% of participants), and serum levels of the proinflammatory TNF-α (from 16.9 ± 1.11 pg/mL to 13.5 ± 0.8 pg/mL, p<0.05). CONCLUSION: A bilingual culturally appropriate community-based CVD-prevention program based on health education, medical screenings, and empowerment is a successful, effective, adaptable, and replicable model to significantly improve cardiometabolic risk in Latinas.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Educación en Salud/organización & administración , Conocimientos, Actitudes y Práctica en Salud , Hispánicos o Latinos/estadística & datos numéricos , Síndrome Metabólico/prevención & control , Evaluación de Procesos y Resultados en Atención de Salud , Adolescente , Adulto , Anciano , Índice de Masa Corporal , Enfermedades Cardiovasculares/etnología , Investigación Participativa Basada en la Comunidad , Femenino , Conductas Relacionadas con la Salud , Humanos , Síndrome Metabólico/etnología , Persona de Mediana Edad , Proyectos Piloto , Prevalencia , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Factores de Riesgo , Conducta de Reducción del Riesgo , Adulto Joven
14.
Am J Physiol Heart Circ Physiol ; 306(1): H109-20, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24163071

RESUMEN

Postprandial lipemia is characterized by a transient increase in circulating triglyceride-rich lipoproteins such as very low-density lipoprotein (VLDL) and has been shown to activate monocytes in vivo. Lipolysis of VLDL releases remnant particles, phospholipids, monoglycerides, diglycerides, and fatty acids in close proximity to endothelial cells and monocytes. We hypothesized that postprandial VLDL lipolysis products could activate and recruit monocytes by increasing monocyte expression of proinflammatory cytokines and adhesion molecules, and that such activation is related to the development of lipid droplets. Freshly isolated human monocytes were treated with VLDL lipolysis products (2.28 mmol/l triglycerides + 2 U/ml lipoprotein lipase), and monocyte adhesion to a primed endothelial monolayer was observed using a parallel plate flow chamber coupled with a CCD camera. Treated monocytes showed more rolling and adhesion than controls, and an increase in transmigration between endothelial cells. The increased adhesive events were related to elevated expression of key integrin complexes including Mac-1 [α(m)-integrin (CD11b)/ß2-integrin (CD18)], CR4 [α(x)-integrin (CD11c)/CD18] and VLA-4 [α4-integrin (CD49d)/ß1-integrin (CD29)] on treated monocytes. Treatment of peripheral blood mononuclear cells (PBMCs) and THP-1 monocytes with VLDL lipolysis products increased expression of TNFα, IL-1ß, and IL-8 over controls, with concurrent activation of NFkB and AP-1. NFκB and AP-1-induced cytokine and integrin expression was dependent on ERK and Akt phosphorylation. Additionally, fatty acids from VLDL lipolysis products induced ERK2-dependent lipid droplet formation in monocytes, suggesting a link to inflammatory signaling pathways. These results provide novel mechanisms for postprandial monocyte activation by VLDL lipolysis products, suggesting new pathways and biomarkers for chronic, intermittent vascular injury.


Asunto(s)
Lipólisis , Lipoproteínas VLDL/metabolismo , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Monocitos/metabolismo , FN-kappa B/metabolismo , Periodo Posprandial , Adolescente , Adulto , Antígenos CD18/genética , Antígenos CD18/metabolismo , Adhesión Celular , Células Cultivadas , Niño , Femenino , Humanos , Integrina alfa4beta1/genética , Integrina alfa4beta1/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Metabolismo de los Lípidos , Lipoproteína Lipasa/farmacología , Sistema de Señalización de MAP Quinasas , Antígeno de Macrófago-1/genética , Antígeno de Macrófago-1/metabolismo , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/fisiología , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor de Transcripción AP-1/genética , Factor de Transcripción AP-1/metabolismo , Migración Transendotelial y Transepitelial , Triglicéridos/farmacología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
15.
Artículo en Inglés | MEDLINE | ID: mdl-26029731

RESUMEN

OBJECTIVE: Alzheimer's disease (AD) is a neurodegenerative disease of aging with unknown causative factors. Accumulating evidence suggests that inflammation and neurovascular dysfunction play important roles in AD. The postprandial period following a moderately high-fat meal is associated with vascular inflammation in young, healthy individuals; however, this relationship has not been investigated in Alzheimer's patients despite their exaggerated inflammatory state. METHODS: Patients with AD and age-matched control subjects were recruited through the UC Davis Alzheimer's Disease Center. All subjects consumed a moderately high-fat breakfast meal. Fasting and postprandial blood samples were collected for lipid, lipoprotein, and oxylipin analyses, as well as assays for cytokine levels and monocyte activation. RESULTS: The plasma lipid analyses revealed similar levels of triglycerides and esterified oxylipins between groups, but there was an interaction between postprandial non-esterified fatty acid (NEFA) levels and body mass index in the AD group compared to the control subjects. The AD group also had increased behenic acid and decreased linoleic and oleic acids in the postprandial period; however, these were not significantly different. Inflammatory assays revealed elevated fasting levels of interleukin (IL)-10 and IL-12 p70, but no change in monocyte activation in the AD group. CONCLUSION: The postprandial period following a moderately high-fat meal is not associated with an exaggerated inflammatory state in Alzheimer's patients, and basal esterified oxylipin profiles do not indicate elevated oxidative stress. However, the baseline inflammatory state during fasting in AD patients includes elevated levels of plasma IL-10 and IL-12 p70, which may indicate a balance between immune responses mediated by these interleukins.

16.
Springerplus ; 2(1): 214, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23741647

RESUMEN

Vascular endothelium expresses both the estrogen receptors (ERs) α and ß, and ERα mediates development of early atherosclerosis in male mice. This process is thought to be testosterone-dependent. We hypothesized that male murine aortic endothelium produces robust levels of estradiol by aromatase conversion of testosterone, and that regulation of this process is mediated by the presence of ERs, primarily ERα. Aortic endothelium was isolated from ERα knockout (ERα -/-) and wild-type (ERα +/+) male mice and treated with testosterone or the 5α reduction product dihydrotestosterone (DHT), with or without the P450 aromatase inhibitor anastrazole, or a non-specific estrogen receptor antagonist. Aromatase gene expression and estradiol production were assayed. Treatment with testosterone, but not DHT, caused increased aromatase expression and estradiol production in ERα +/+ endothelium that was attenuated by disruption of ERα in the ERα -/- group. Anastrazole inhibition of aromatase reduced testosterone-induced aromatase expression and estradiol levels in both ERα -/- and ERα +/+ endothelium. Antagonism of both ERs decreased testosterone-induced aromatase expression in both wild-type and knockout groups. The effects of the receptor antagonist on estradiol production differed between the two groups, however, with a reduction in estradiol release from the ERα +/+ cells and complete abolition of estradiol release from the ERα -/- cells. Thus, estradiol production in vascular endothelium from male mice is robust, depends on the aromatic conversion of testosterone and requires functional ERα to achieve maximal levels of estradiol generation. Local vascular production of aromatase-mediated estradiol in response to circulating testosterone may affect ERα-dependent mechanisms to increase susceptibility to early atheroma formation in male mice. This pathway may have important therapeutic relevance for reducing the risk of atherosclerotic cardiovascular disease in human males.

17.
J Biol Chem ; 288(17): 11628-35, 2013 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-23430745

RESUMEN

One of the primary neuropathological hallmarks of Alzheimer disease is the presence of extracellular amyloid plaques resulting from the aggregation of amyloid-ß (Aß) peptides. The intrinsic disorder of the Aß peptide drives self-association and progressive reordering of the conformation in solution, and this dynamic distribution of Aß complicates biophysical studies. This property poses a challenge for understanding the interaction of Aß with apolipoprotein E (apoE). ApoE plays a pivotal role in the aggregation and clearance of Aß peptides in the brain, and the ε4 allele of APOE is the most significant known genetic modulator of Alzheimer risk. Understanding the interaction between apoE and Aß will provide insight into the mechanism by which different apoE isoforms determine Alzheimer disease risk. Here we applied alternating laser excitation fluorescence cross-correlation spectroscopy to observe the single molecule interaction of Aß with apoE in the hydrated state. The diffusion time of freely diffusing Aß in the absence of apoE shows significant self-aggregation, whereas in the presence of apoE, binding of the protein results in a more stable complex. These results show that apoE slows down the oligomerization of Aß in solution and provide direct insight into the process by which apoE influences the deposition and clearance of Aß peptides in the brain. Furthermore, by developing an approach to remove signals arising from very large Aß aggregates, we show that real-time single particle observations provide access to information regarding the fraction of apoE bound and the stoichiometry of apoE and Aß in the complex.


Asunto(s)
Péptidos beta-Amiloides/química , Apolipoproteínas E/química , Multimerización de Proteína , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Humanos , Unión Proteica , Isoformas de Proteínas , Espectrometría de Fluorescencia
18.
J Pediatr ; 163(1): 94-9.e1-6, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23415612

RESUMEN

OBJECTIVE: To determine in patients who are well-appearing and without a clear etiology after an apparent life-threatening event (ALTE): (1) What historical and physical examination features suggest that a child is at risk for a future adverse event and/or serious underlying diagnosis and would, therefore, benefit from testing or hospitalization? and (2) What testing is indicated on presentation and during hospitalization? STUDY DESIGN: Systematic review of clinical studies, excluding case reports, published from 1970 through 2011 identified using key words for ALTE. RESULTS: The final analysis was based on 37 studies; 18 prospective observational, 19 retrospective observational. None of the studies provided sufficient evidence to fully address the clinical questions. Risk factors identified from historical and physical examination features included a history of prematurity, multiple ALTEs, and suspected child maltreatment. Routine screening tests for gastroesophageal reflux, meningitis, bacteremia, and seizures are low yield in infants without historical risk factors or suggestive physical examination findings. CONCLUSION: Some historical and physical examination features can be used to identify risk in infants who are well-appearing and without a clear etiology at presentation, and testing tailored to these risks may be of value. The true risk of a subsequent event or underlying disorder cannot be ascertained. A more precise definition of an ALTE is needed and further research is warranted.


Asunto(s)
Evento Inexplicable, Breve y Resuelto/diagnóstico , Humanos , Lactante
19.
PLoS One ; 7(11): e50513, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23209766

RESUMEN

OBJECTIVE: Postprandial hyperlipemia, characterized by increased circulating very low-density lipoproteins (VLDL) and circulating lipopolysaccharide (LPS), has been proposed as a mechanism of vascular injury. Our goal was to examine the interactions between postprandial lipoproteins, LPS, and apoE3 and apoE4 on monocyte activation. METHODS AND RESULTS: We showed that apoE3 complexed to phospholipid vesicles attenuates LPS-induced THP-1 monocyte cytokine expression, while apoE4 increases expression. ELISA revealed that apoE3 binds to LPS with higher affinity than apoE4. Electron paramagnetic resonance (EPR) spectroscopy of site-directed spin labels placed on specific amino acids of apoE3 showed that LPS interferes with conformational changes normally associated with lipid binding. Specifically, compared to apoE4, apoE bearing the E3-like R112→Ser mutation displays increased self association when exposed to LPS, consistent with a stronger apoE3-LPS interaction. Additionally, lipolysis of fasting VLDL from normal human donors attenuated LPS-induced TNFα secretion from monocytes to a greater extent than postprandial VLDL, an effect partially reversed by blocking apoE. This effect was reproduced using fasting VLDL lipolysis products from e3/e3 donors, but not from e4/e4 subjects, suggesting that apoE3 on fasting VLDL prevents LPS-induced inflammation more readily than apoE4. CONCLUSION: Postprandial apoE isoform and conformational changes associated with VLDL dramatically modulate vascular inflammation.


Asunto(s)
Apolipoproteínas E/química , Apolipoproteínas E/metabolismo , Lipólisis/efectos de los fármacos , Lipoproteínas VLDL/metabolismo , Monocitos/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Adolescente , Adulto , Apolipoproteína E3/química , Apolipoproteína E3/metabolismo , Apolipoproteína E3/farmacología , Apolipoproteína E4/química , Apolipoproteína E4/metabolismo , Apolipoproteína E4/farmacología , Apolipoproteínas E/farmacología , Línea Celular , Espectroscopía de Resonancia por Spin del Electrón , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lipopolisacáridos , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/inmunología , Isoformas de Proteínas/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Necrosis Tumoral alfa/metabolismo , Adulto Joven
20.
PLoS One ; 7(4): e35443, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22558151

RESUMEN

BACKGROUND: The deposition and oligomerization of amyloid ß (Aß) peptide plays a key role in the pathogenesis of Alzheimer's disease (AD). Aß peptide arises from cleavage of the membrane-associated domain of the amyloid precursor protein (APP) by ß and γ secretases. Several lines of evidence point to the soluble Aß oligomer (AßO) as the primary neurotoxic species in the etiology of AD. Recently, we have demonstrated that a class of fluorene molecules specifically disrupts the AßO species. METHODOLOGY/PRINCIPAL FINDINGS: To achieve a better understanding of the mechanism of action of this disruptive ability, we extend the application of electron paramagnetic resonance (EPR) spectroscopy of site-directed spin labels in the Aß peptide to investigate the binding and influence of fluorene compounds on AßO structure and dynamics. In addition, we have synthesized a spin-labeled fluorene (SLF) containing a pyrroline nitroxide group that provides both increased cell protection against AßO toxicity and a route to directly observe the binding of the fluorene to the AßO assembly. We also evaluate the ability of fluorenes to target multiple pathological processes involved in the neurodegenerative cascade, such as their ability to block AßO toxicity, scavenge free radicals and diminish the formation of intracellular AßO species. CONCLUSIONS: Fluorene modified with pyrroline nitroxide may be especially useful in counteracting Aß peptide toxicity, because they possess both antioxidant properties and the ability to disrupt AßO species.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Espectroscopía de Resonancia por Spin del Electrón/métodos , Fluorenos/metabolismo , Depuradores de Radicales Libres/metabolismo , Modelos Biológicos , Marcadores de Spin , Péptidos beta-Amiloides/toxicidad , Western Blotting , Línea Celular Tumoral , Dicroismo Circular , Fluorenos/química , Técnica del Anticuerpo Fluorescente , Humanos , Microscopía de Fuerza Atómica , Estructura Molecular , Óxidos de Nitrógeno/metabolismo , Sales de Tetrazolio , Tiazoles
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