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1.
Int J Mol Sci ; 25(16)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39201339

RESUMEN

In polymicrobial sepsis, the extracellular histones, mainly released from activated neutrophils, significantly contribute to cardiac dysfunction (septic cardiomyopathy), as demonstrated in our previous studies using Echo-Doppler measurements. This study aims to elucidate the roles of extracellular histones and their interactions with Toll-like receptors (TLRs) in cardiac dysfunction. Through ex vivo assessments of ECG, left ventricle (LV) function parameters, and in vivo Echo-Doppler studies in mice perfused with extracellular histones, we aim to provide comprehensive insights into the mechanisms underlying sepsis-induced cardiac dysfunction. Langendorff-perfused hearts from both wild-type and TLR2, TLR3, or TLR4 knockout (KO) mice were examined. Paced mouse hearts were perfused with histones to assess contractility and relaxation. Echo-Doppler studies evaluated cardiac dysfunction after intravenous histone injection. Histone perfusion caused defects in contractility and relaxation, with TLR2 and TLR3 KO mice being partially protected. Specifically, TLR2 KO mice exhibited the greatest reduction in Echo-Doppler abnormalities, while TLR4 KO exacerbated cardiac dysfunction. Among individual histones, H1 induced the most pronounced abnormalities in cardiac function, apoptosis of cardiomyocytes, and LDH release. Our data highlight significant interactions between histones and TLRs, providing insights into histones especially H1 as potential therapeutic targets for septic cardiomyopathy. Further studies are needed to explore specific histone-TLR interactions and their mechanisms.


Asunto(s)
Histonas , Ratones Noqueados , Animales , Histonas/metabolismo , Ratones , Receptores Toll-Like/metabolismo , Masculino , Sepsis/metabolismo , Sepsis/complicaciones , Ratones Endogámicos C57BL , Miocitos Cardíacos/metabolismo , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 2/genética , Corazón/fisiopatología
2.
Clin Infect Dis ; 77(2): 186-193, 2023 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-36996150

RESUMEN

BACKGROUND: The vast majority of coronavirus disease 2019 (COVID-19) disease occurs in outpatients where treatment is limited to antivirals for high-risk subgroups. Acebilustat, a leukotriene B4 inhibitor, has potential to reduce inflammation and symptom duration. METHODS: In a single-center trial spanning Delta and Omicron variants, outpatients were randomized to 100 mg/d of oral acebilustat or placebo for 28 days. Patients reported daily symptoms via electronic query through day 28 with phone follow-up on day 120 and collected nasal swab samples on days 1-10. The primary outcome was sustained symptom resolution to day 28. Secondary 28-day outcomes included time to first symptom resolution, area under the curve (AUC) for longitudinal daily symptom scores, duration of viral shedding through day 10, and symptoms on day 120. RESULTS: Sixty participants were randomized to each study arm. At enrollment, the median duration was 4 days (interquartile range, 3-5 days), and the median number of symptoms was 9 (7-11). Most patients (90%) were vaccinated, with 73% having neutralizing antibodies. A minority of participants (44%; 35% in the acebilustat arm and 53% in placebo) had sustained symptom resolution at day 28 (hazard ratio, 0.6 [95% confidence interval, .34-1.04]; P = .07 favoring placebo). There was no difference in the mean AUC for symptom scores over 28 days (difference in mean AUC, 9.4 [95% confidence interval, -42.1 to 60.9]; P = .72). Acebilustat did not affect viral shedding or symptoms at day 120. CONCLUSIONS: Sustained symptoms through day 28 were common in this low-risk population. Despite this, leukotriene B4 antagonism with acebilustat did not shorten symptom duration in outpatients with COVID-19. Clinical Trials Registration. NCT04662060.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Leucotrieno B4 , Pacientes Ambulatorios , Método Doble Ciego , Resultado del Tratamiento
3.
Ann Surg ; 277(1): e226-e234, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33714966

RESUMEN

OBJECTIVE: The aim of this study was to describe decisions about the escalation and withdrawal of treatment for patients on extracorporeal membrane oxygenation (ECMO). SUMMARY BACKGROUND DATA: Interventions premised on facilitating patient autonomy have proven problematic in guiding treatment decisions in intensive care units (ICUs). Calls have thus been made to better understand how decisions are made in critical care. ECMO is an important form of cardiac and respiratory support, but care on ECMO is characterized by prognostic uncertainty, varying time course, and high resource use. It remains unclear how decisions about treatment escalation and withdrawal should be made for patients on ECMO and what role families should play in these decisions. METHODS: We performed a focused ethnography in 2 cardiothoracic ICUs in 2 US academic hospitals. We conducted 380 hours of observation, 34 weekly interviews with families of 20 ECMO patients, and 13 interviews with unit clinicians from January to September 2018. Qualitative analysis used an iterative coding process. RESULTS: Following ECMO initiation, treatment was escalated as complications mounted until the patient either could be decannulated or interventional options were exhausted. Families were well-informed about treatment and prognosis but played minimal roles in shaping the trajectory of care. CONCLUSIONS: Discussion between clinicians and families about prognosis and goals was frequent but did not occasion decision-making moments. This study helps explain why communication interventions intended to maintain patient autonomy through facilitating surrogate participation in decisions have had limited impact. A more comprehensive understanding of upstream factors that predispose courses of critical care is needed.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Humanos , Pronóstico , Unidades de Cuidados Intensivos , Cuidados Críticos
4.
Vaccine ; 41(3): 750-755, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36526502

RESUMEN

INTRODUCTION: Public health department (PHD) led COVID-19 vaccination clinics can be a critical component of pandemic response as they facilitate high volume of vaccination. However, few patient-time analyses examining patient throughput at mass vaccination clinics with unique COVID-19 vaccination challenges have been published. METHODS: During April and May of 2021, 521 patients in 23 COVID-19 vaccination sites counties of 6 states were followed to measure the time spent from entry to vaccination. The total time was summarized and tabulated by clinic characteristics. A multivariate linear regression analysis was conducted to evaluate the association between vaccination clinic settings and patient waiting times in the clinic. RESULTS: The average time a patient spent in the clinic from entry to vaccination was 9 min 5 s (range: 02:00-23:39). Longer patient flow times were observed in clinics with higher numbers of doses administered, 6 or fewer vaccinators, walk-in patients accepted, dedicated services for people with disabilities, and drive-through clinics. The multivariate linear regression showed that longer patient waiting times were significantly associated with the number of vaccine doses administered, dedicated services for people with disabilities, the availability of more than one brand of vaccine, and rurality. CONCLUSIONS: Given the standardized procedures outlined by immunization guidelines, reducing the wait time is critical in lowering the patient flow time by relieving the bottleneck effect in the clinic. Our study suggests enhancing the efficiency of PHD-led vaccination clinics by preparing vaccinators to provide vaccines with proper and timely support such as training or delivering necessary supplies and paperwork to the vaccinators. In addition, patient wait time can be spent answering questions about vaccination or reviewing educational materials on other public health services.


Asunto(s)
COVID-19 , Vacunas , Humanos , Estados Unidos , Vacunas contra la COVID-19 , COVID-19/prevención & control , Vacunación , Vacunación Masiva
5.
Physiol Rep ; 10(17): e15340, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36073059

RESUMEN

In cystic fibrosis (CF), the loss of cystic fibrosis transmembrane conductance regulator (CFTR) mediated Cl-  and HCO3 -  secretion across the epithelium acidifies the airway surface liquid (ASL). Acidic ASL alters two key host defense mechanisms: Rapid ASL bacterial killing and mucociliary transport (MCT). Aerosolized tromethamine (Tham) increases ASL pH and restores the ability of ASL to rapidly kill bacteria in CF pigs. In CF pigs, clearance of insufflated microdisks is interrupted due to abnormal mucus causing microdisks to abruptly recoil. Aerosolizing a reducing agent to break disulfide bonds that link mucins improves MCT. Here, we are interested in restoring MCT in CF by aerosolizing Tham, a buffer with a pH of 8.4. Because Tham is hypertonic to serum, we use an acidified formulation as a control. We measure MCT by tracking the caudal movement of individual tantalum microdisks with serial chest computed tomography scans. Alkaline Tham improves microdisk clearance to within the range of that seen in non-CF pigs. It also partially reverses MCT defects, including reduced microdisk recoil and elapse time until they start moving after methacholine stimulation in CF pig airways. The effect is not due to hypertonicity, as it is not seen with acidified Tham or hypertonic saline. This finding indicates acidic ASL impairs CF MCT and suggests that alkalinization of ASL pH with inhaled Tham may improve CF airway disease.


Asunto(s)
Fibrosis Quística , Animales , Bicarbonatos , Fibrosis Quística/tratamiento farmacológico , Depuración Mucociliar , Mucosa Respiratoria , Porcinos , Trometamina
6.
J Public Health Manag Pract ; 28(6): 624-630, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36037518

RESUMEN

OBJECTIVES: To estimate the costs to implement public health department (PHD)-run COVID-19 vaccination clinics. DESIGN: Retrospectively reported data on COVID-19 vaccination clinic characteristics and resources used during a high-demand day in March 2021. These resources were combined with national average wages, supply costs, and facility costs to estimate the operational cost and start-up cost of clinics. SETTING: Thirty-four PHD-run COVID-19 vaccination clinics across 8 states and 1 metropolitan statistical area. PARTICIPANTS: Clinic managers at 34 PHD-run COVID-19 vaccination clinics. INTERVENTION: Large-scale COVID-19 vaccination clinics were implemented by public health agencies as part of the pandemic response. MAIN OUTCOMES MEASURED: Operational cost per day, operational cost per vaccination, start-up cost per clinic. RESULTS: Median operational cost per day for a clinic was $10 314 (range, $637-$95 163) and median cost per vaccination was $38 (range, $9-$206). There was a large range of operational costs across clinics. Clinics used an average of 99 total staff hours per 100 patients vaccinated. Median start-up cost per clinic was $15 348 (range, $1 409-$165 190). CONCLUSIONS: Results show that clinics require a large range of resources to meet the high throughput needs of the COVID-19 pandemic response. Estimating the costs of PHD-run vaccination clinics for the pandemic response is essential for ensuring that resources are available for clinic success. If clinics are not adequately supported, they may stop functioning, which would slow the pandemic response if no other setting or approach is possible.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19/uso terapéutico , Humanos , Pandemias , Estudios Retrospectivos , Estados Unidos/epidemiología , Vacunación
7.
BMJ Open ; 12(4): e059914, 2022 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-35450913

RESUMEN

INTRODUCTION: South Africa's evolving burden of disease is challenging due to a persistent infectious disease, burgeoning obesity, most notably among women and rising rates of non-communicable diseases (NCDs). With two thirds of women presenting at their first antenatal visit either overweight or obese in urban South Africa (SA), the preconception period is an opportunity to optimise health and offset transgenerational risk of both obesity and NCDs. METHODS AND ANALYSIS: Bukhali is the first individual randomised controlled trial in Africa to test the efficacy of a complex continuum of care intervention and forms part of the Healthy Life Trajectories Initiative (HeLTI) consortium implementing harmonised trials in Canada, China, India and SA. Starting preconception and continuing through pregnancy, infancy and childhood, the intervention is designed to improve nutrition, physical and mental health and health behaviours of South African women to offset obesity-risk (adiposity) in their offspring. Women aged 18-28 years (n=6800) will be recruited from Soweto, an urban-poor area of Johannesburg. The primary outcome is dual-energy X-ray absorptiometry derived fat mass index (fat mass divided by height2) in the offspring at age 5 years. Community health workers will deliver the intervention randomly to half the cohort by providing health literacy material, dispensing a multimicronutrient supplement, providing health services and feedback, and facilitating behaviour change support sessions to optimise: (1) nutrition, (2) physical and mental health and (3) lay the foundations for healthier pregnancies and early child development. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Human Ethics Research Committee University of the Witwatersrand, Johannesburg, South Africa (M1811111), the University of Toronto, Canada (19-0066-E) and the WHO Ethics Committee (ERC.0003328). Data and biological sample sharing policies are consistent with the governance policy of the HeLTI Consortium (https://helti.org) and South African government legislation (POPIA). The recruitment and research team will obtain informed consent. TRIAL REGISTRATION: This trial is registered with the Pan African Clinical Trials Registry (https://pactr.samrc.ac.za) on 25 March 2019 (identifier: PACTR201903750173871). PROTOCOL VERSION: 20 March 2022 (version #4). Any protocol amendments will be communicated to investigators, Institutional Review Board (IRB)s, trial participants and trial registries.


Asunto(s)
Estado de Salud , Salud Mental , Niño , Preescolar , Agentes Comunitarios de Salud , Femenino , Humanos , Masculino , Obesidad/prevención & control , Embarazo , Sudáfrica
8.
Anesthesiology ; 135(1): 111-121, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33891695

RESUMEN

BACKGROUND: Calls to better involve patients in decisions about anesthesia-e.g., through shared decision-making-are intensifying. However, several features of anesthesia consultation make it unclear how patients should participate in decisions. Evaluating the feasibility and desirability of carrying out shared decision-making in anesthesia requires better understanding of preoperative conversations. The objective of this qualitative study was to characterize how preoperative consultations for primary knee arthroplasty arrived at decisions about primary anesthesia. METHODS: This focused ethnography was performed at a U.S. academic medical center. The authors audio-recorded consultations of 36 primary knee arthroplasty patients with eight anesthesiologists. Patients and anesthesiologists also participated in semi-structured interviews. Consultation and interview transcripts were coded in an iterative process to develop an explanation of how anesthesiologists and patients made decisions about primary anesthesia. RESULTS: The authors found variation across accounts of anesthesiologists and patients as to whether the consultation was a collaborative decision-making scenario or simply meant to inform patients. Consultations displayed a number of decision-making patterns, from the anesthesiologist not disclosing options to the anesthesiologist strictly adhering to a position of equipoise; however, most consultations fell between these poles, with the anesthesiologist presenting options, recommending one, and persuading hesitant patients to accept it. Anesthesiologists made patients feel more comfortable with their proposed approach through extensive comparisons to more familiar experiences. CONCLUSIONS: Anesthesia consultations are multifaceted encounters that serve several functions. In some cases, the involvement of patients in determining the anesthetic approach might not be the most important of these functions. Broad consideration should be given to both the applicability and feasibility of shared decision-making in anesthesia consultation. The potential benefits of interventions designed to enhance patient involvement in decision-making should be weighed against their potential to pull anesthesiologists' attention away from important humanistic aspects of communication such as decreasing patients' anxiety.


Asunto(s)
Anestesia/métodos , Artroplastia de Reemplazo de Rodilla , Toma de Decisiones Clínicas/métodos , Participación del Paciente/métodos , Centros Médicos Académicos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Participación del Paciente/estadística & datos numéricos , Investigación Cualitativa , Estados Unidos
9.
J Immunol ; 205(1): 251-260, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32444389

RESUMEN

Over the first days of polymicrobial sepsis, there is robust activation of the innate immune system, causing the appearance of proinflammatory cytokines and chemokines, along with the appearance of extracellular histones, which are highly proinflammatory and prothrombotic. In the current study, we studied different innate immune responses in mice with knockout (KO) of complement protein 6 (C6). Polymorphonuclear neutrophils (PMNs) from these KO mice had defective innate immune responses, including defective expression of surface adhesion molecules, generation of superoxide anion, and appearance of reactive oxygen species and histone release after activation of PMNs, along with defective phagocytosis. In addition, in C6-/- mice, the NLRP3 inflammasome was defective both in PMNs and in macrophages. When these KO mice were subjected to polymicrobial sepsis, their survival was improved, associated with reduced levels in the plasma of proinflammatory cytokines and chemokines and lower levels of histones in plasma. In addition, sepsis-induced cardiac dysfunction was attenuated in these KO mice. In a model of acute lung injury induced by LPS, C6-/- mice showed reduced PMN buildup and less lung epithelial/endothelial cell dysfunction (edema and hemorrhage). These data indicate that C6-/- mice have reduced innate immune responses that result in less organ injury and improved survival after polymicrobial sepsis.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Cardiomiopatías/inmunología , Coinfección/inmunología , Complemento C6/metabolismo , Inmunidad Innata , Sepsis/inmunología , Lesión Pulmonar Aguda/diagnóstico , Lesión Pulmonar Aguda/patología , Animales , Cardiomiopatías/diagnóstico , Cardiomiopatías/patología , Coinfección/complicaciones , Coinfección/diagnóstico , Coinfección/patología , Complemento C6/genética , Modelos Animales de Enfermedad , Humanos , Inflamasomas/inmunología , Inflamasomas/metabolismo , Masculino , Ratones , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Sepsis/complicaciones , Sepsis/diagnóstico , Sepsis/genética , Índice de Severidad de la Enfermedad
10.
Am J Kidney Dis ; 75(1): 61-71, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31492489

RESUMEN

RATIONALE & OBJECTIVE: Collaboration between nephrology consultants and intensive care unit (ICU) teams is important in light of the high incidence of acute kidney injury in today's ICUs. Although there is considerable debate about how nephrology consultants and ICU teams should collaborate, communicative dynamics between the 2 parties remain poorly understood. This article describes interactions between nephrology consultants and ICU teams in the academic medical setting. STUDY DESIGN: Focused ethnography using semi-structured interviews and participant observation. SETTING & PARTICIPANTS: Purposive sampling was used to enroll nephrologists, nephrology fellows, and ICU practitioners across several roles collaborating in 3 ICUs (a medical ICU, a surgical ICU, and a cardiothoracic surgical ICU) of a large urban US academic medical center. Participant observation (150 hours) and semi-structured interviews (35) continued until theoretical saturation. ANALYTICAL APPROACH: Interview and fieldnote transcripts were coded in an iterative team-based process. Explanation was developed using an abductive approach. RESULTS: Nephrology consultants and surgical ICU teams exhibited discordant preferences about the aggressiveness of renal replacement therapy based on different understandings of physiology, goals of care, and acuity. Collaborative difficulties resulting from this discordance led to nephrology consultants often serving as dialysis proceduralists rather than diagnosticians in surgical ICUs and to consultants sometimes choosing not to express disagreements about clinical care because of the belief that doing so would not lead to changes in the course of care. LIMITATIONS: Aspects of this single-site study of an academic medical center may not be generalizable to other clinical settings and samples. Surgical team perspectives would provide further detail about nephrology consultation in surgical ICUs. The effects of findings on patient care were not examined. CONCLUSIONS: Differences in approach between internal medicine-trained nephrologists and anesthesia- and surgery-trained intensivists and surgeons led to collaborative difficulties in surgical ICUs. These findings stress the need for medical teamwork research and intervention to address issues stemming from disciplinary siloing rooted in long-term socialization to different disciplinary practices.


Asunto(s)
Cuidados Críticos , Unidades de Cuidados Intensivos , Comunicación Interdisciplinaria , Nefrología , Centros Médicos Académicos , Antropología Cultural , Conducta Cooperativa , Enfermería de Cuidados Críticos , Toma de Decisiones Asistida por Computador , Femenino , Humanos , Masculino , Grupo de Atención al Paciente , Investigación Cualitativa , Terapia de Reemplazo Renal
12.
Elife ; 62017 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-28650315

RESUMEN

Attenuating the strength of fearful memories could benefit people disabled by memories of past trauma. Pavlovian conditioning experiments indicate that a retrieval cue can return a conditioned aversive memory to a labile state. However, means to enhance retrieval and render a memory more labile are unknown. We hypothesized that augmenting synaptic signaling during retrieval would increase memory lability. To enhance synaptic transmission, mice inhaled CO2 to induce an acidosis and activate acid sensing ion channels. Transient acidification increased the retrieval-induced lability of an aversive memory. The labile memory could then be weakened by an extinction protocol or strengthened by reconditioning. Coupling CO2 inhalation to retrieval increased activation of amygdala neurons bearing the memory trace and increased the synaptic exchange from Ca2+-impermeable to Ca2+-permeable AMPA receptors. The results suggest that transient acidosis during retrieval renders the memory of an aversive event more labile and suggest a strategy to modify debilitating memories.


Asunto(s)
Acidosis , Miedo , Memoria , Amígdala del Cerebelo/fisiología , Animales , Dióxido de Carbono/metabolismo , Condicionamiento Clásico , Ratones , Receptores AMPA/metabolismo
13.
J Autism Dev Disord ; 47(5): 1314-1322, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28168677

RESUMEN

Autism spectrum disorder (ASD) affects individuals across all racial and ethnic groups, yet rates of diagnosis are disproportionately higher for Black and Hispanic children. Caregivers of children with ASD experience significant stressors, which have been associated with parental strain, inadequate utilization of mental health services and lower quality of life. The family peer advocate (FPA) model has been utilized across service delivery systems to provide family-to-family support, facilitate engagement, and increase access to care. This study used a randomized controlled design to examine the efficacy of FPAs in a racially and ethnically diverse sample. Results demonstrate significantly increased knowledge of ASD and reduced levels of stress for caregivers who received the FPA intervention as compared to treatment as usual.


Asunto(s)
Trastorno del Espectro Autista/enfermería , Negro o Afroamericano/psicología , Cuidadores/psicología , Terapia Familiar , Hispánicos o Latinos/psicología , Padres/psicología , Estrés Psicológico/terapia , Adulto , Niño , Preescolar , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Servicios de Salud Mental , Aceptación de la Atención de Salud/psicología , Grupo Paritario , Calidad de Vida , Método Simple Ciego
14.
J Innate Immun ; 9(3): 300-317, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28171866

RESUMEN

Histones invoke strong proinflammatory responses in many different organs and cells. We assessed biological responses to purified or recombinant histones, using human and murine phagocytes and mouse lungs. H1 had the strongest ability in vitro to induce cell swelling independent of requirements for toll-like receptors (TLRs) 2 or 4. These responses were also associated with lactate dehydrogenase release. H3 and H2B were the strongest inducers of [Ca2+]i elevations in phagocytes. Cytokine and chemokine release from mouse and human phagocytes was predominately a function of H2A and H2B. Double TLR2 and TLR4 knockout (KO) mice had dramatically reduced cytokine release induced in macrophages exposed to individual histones. In contrast, macrophages from single TLR-KO mice showed few inhibitory effects on cytokine production. Using the NLRP3 inflammasome protocol, release of mature IL-1ß was predominantly a feature of H1. Acute lung injury following the airway delivery of histones suggested that H1, H2A, and H2B were linked to alveolar leak of albumin and the buildup of polymorphonuclear neutrophils as well as the release of chemokines and cytokines into bronchoalveolar fluids. These results demonstrate distinct biological roles for individual histones in the context of inflammation biology and the requirement of both TLR2 and TLR4.


Asunto(s)
Histonas/inmunología , Inflamasomas/metabolismo , Inflamación/inmunología , Pulmón/inmunología , Fagocitos/inmunología , Animales , Células Cultivadas , Humanos , Interleucina-1beta/metabolismo , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
15.
J Immunol ; 197(6): 2353-61, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27521340

RESUMEN

There is accumulating evidence during sepsis that cardiomyocyte (CM) homeostasis is compromised, resulting in cardiac dysfunction. An important role for complement in these outcomes is now demonstrated. Addition of C5a to electrically paced CMs caused prolonged elevations of intracellular Ca(2+) concentrations during diastole, together with the appearance of spontaneous Ca(2+) transients. In polymicrobial sepsis in mice, we found that three key homeostasis-regulating proteins in CMs were reduced: Na(+)/K(+)-ATPase, which is vital for effective action potentials in CMs, and two intracellular Ca(2+) concentration regulatory proteins, that is, sarcoplasmic/endoplasmic reticulum calcium ATPase 2 and the Na(+)/Ca(2+) exchanger. Sepsis caused reduced mRNA levels and reductions in protein concentrations in CMs for all three proteins. The absence of either C5a receptor mitigated sepsis-induced reductions in the three regulatory proteins. Absence of either C5a receptor (C5aR1 or C5aR2) diminished development of defective systolic and diastolic echocardiographic/Doppler parameters developing in the heart (cardiac output, left ventricular stroke volume, isovolumic relaxation, E' septal annulus, E/E' septal annulus, left ventricular diastolic volume). We also found in CMs from septic mice the presence of defective current densities for Ik1, l-type calcium channel, and Na(+)/Ca(2+) exchanger. These defects were accentuated in the copresence of C5a. These data suggest complement-related mechanisms responsible for development of cardiac dysfunction during sepsis.


Asunto(s)
Coinfección/inmunología , Miocitos Cardíacos/inmunología , Miocitos Cardíacos/patología , Sepsis/inmunología , Sepsis/fisiopatología , Animales , Calcio/metabolismo , Canales de Calcio Tipo L/inmunología , Coinfección/microbiología , Coinfección/fisiopatología , Complemento C5a/inmunología , Citoplasma/química , Citoplasma/metabolismo , Corazón/fisiopatología , Ratones , Miocitos Cardíacos/microbiología , Receptor de Anafilatoxina C5a/deficiencia , Receptor de Anafilatoxina C5a/inmunología , Receptor de Anafilatoxina C5a/fisiología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/inmunología , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo , Sepsis/complicaciones
16.
FASEB J ; 30(12): 3997-4006, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27543123

RESUMEN

Cardiac dysfunction develops during sepsis in humans and rodents. In the model of polymicrobial sepsis induced by cecal ligation and puncture (CLP), we investigated the role of the NLRP3 inflammasome in the heart. Mouse heart homogenates from sham-procedure mice contained high mRNA levels of NLRP3 and IL-1ß. Using the inflammasome protocol, exposure of cardiomyocytes (CMs) to LPS followed by ATP or nigericin caused release of mature IL-1ß. Immunostaining of left ventricular frozen sections before and 8 h after CLP revealed the presence of NLRP3 and IL-1ß proteins in CMs. CLP caused substantial increases in mRNAs for IL-1ß and NLRP3 in CMs which are reduced in the absence of either C5aR1 or C5aR2. After CLP, NLRP3-/- mice showed reduced plasma levels of IL-1ß and IL-6. In vitro exposure of wild-type CMs to recombinant C5a (rC5a) caused elevations in both cytosolic and nuclear/mitochondrial reactive oxygen species (ROS), which were C5a-receptor dependent. Use of a selective NOX2 inhibitor prevented increased cytosolic and nuclear/mitochondrial ROS levels and release of IL-1ß. Finally, NLRP3-/- mice had reduced defects in echo/Doppler parameters in heart after CLP. These studies establish that the NLRP3 inflammasome contributes to the cardiomyopathy of polymicrobial sepsis.-Kalbitz, M., Fattahi, F., Grailer, J. J., Jajou, L., Malan, E. A., Zetoune, F. S., Huber-Lang, M., Russell, M. W., Ward, P. A. Complement-induced activation of the cardiac NLRP3 inflammasome in sepsis.


Asunto(s)
Complemento C5a/metabolismo , Inflamasomas/metabolismo , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sepsis/metabolismo , Animales , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ratones , Ratas , Especies Reactivas de Oxígeno/metabolismo
17.
Mediators Inflamm ; 2016: 1340156, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27382187

RESUMEN

C5a is an inflammatory mediator generated by complement activation that positively regulates various arms of immune defense, including Toll-like receptor 4 (TLR4) signaling. The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome is activated by pathogen products and cellular/tissue damage products and is a major contributor of IL-1ß. In this study, we investigate whether C5a modulates lipopolysaccharide- (LPS-) induced NLRP3 inflammasome activation in myeloid cells. Appearance of plasma IL-1ß during endotoxemia was reduced in C5aR1(-/-) mice when compared to wild-type mice. In vitro, C5a significantly enhanced LPS-induced production of IL-1ß in bone marrow Ly6C-high inflammatory monocytes, accompanied by augmented intracellular pro-IL-1ß expression. This effect was abolished during p38 blockade by SB 203580 and in the absence of C5aR1. Conversely, C5a suppressed LPS-induced macrophage production of IL-1ß, which was accompanied by attenuated levels of pro-IL-1ß, NLRP3, and caspase-1 expression. C5a's suppressive effects were negated during phosphoinositide 3-kinase (PI3K) inhibition by wortmannin but were largely preserved in the absence of C5aR1. Thus, C5a bidirectionally amplifies TLR4-mediated NLRP3 inflammasome activation in monocytes while suppressing this pathway in macrophages. However, as C5aR1 deficiency attenuates the IL-1ß response to LPS challenge in vivo, our results suggest overall that C5a augments physiologic inflammasome responses.


Asunto(s)
Inflamasomas/metabolismo , Macrófagos/metabolismo , Monocitos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Receptor de Anafilatoxina C5a/metabolismo , Animales , Western Blotting , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Complemento C5a/metabolismo , Complemento C5a/farmacología , Modelos Animales de Enfermedad , Endotoxemia/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Inflamasomas/efectos de los fármacos , Interleucina-1beta/metabolismo , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Monocitos/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Receptor de Anafilatoxina C5a/deficiencia , Receptor de Anafilatoxina C5a/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
J Pineal Res ; 60(4): 405-14, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26888116

RESUMEN

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are clinically severe respiratory disorders, and there are currently no Food and Drug Administration-approved drug therapies. Melatonin is a well-known anti-inflammatory molecule, which has proven to be effective in ALI induced by many conditions. Emerging studies suggest that the NLRP3 inflammasome plays a critical role during ALI. How melatonin directly blocks activation of the NLRP3 inflammasome in ALI remains unclear. In this study, using an LPS-induced ALI mouse model, we found intratracheal (i.t.) administration of melatonin markedly reduced the pulmonary injury and decreased the infiltration of macrophages and neutrophils into lung. During ALI, the NLRP3 inflammasome is significantly activated with a large amount of IL-1ß and the activated caspase-1 occurring in the lung. Melatonin inhibits the activation of the NLRP3 inflammasome by both suppressing the release of extracellular histones and directly blocking histone-induced NLRP3 inflammasome activation. Notably, i.t. route of melatonin administration opens a more efficient therapeutic approach for treating ALI.


Asunto(s)
Lesión Pulmonar Aguda/patología , Antiinflamatorios/farmacología , Inflamasomas/efectos de los fármacos , Melatonina/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Lesión Pulmonar Aguda/metabolismo , Animales , Western Blotting , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Inflamasomas/metabolismo , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Especies Reactivas de Oxígeno/metabolismo , Microtomografía por Rayos X
19.
Artículo en Inglés | MEDLINE | ID: mdl-28596876

RESUMEN

BACKGROUND: By 2009, two decades of war and widespread displacement left the majority of the population of Northern Uganda impoverished. METHODS: This study used a cluster-randomized design to test the hypothesis that a poverty alleviation program would improve economic security and reduce symptoms of depression in a sample of mostly young women. Roughly 120 villages in Northern Uganda were invited to participate. Community committees were asked to identify the most vulnerable women (and some men) to participate. The implementing agency screened all proposed participants, and a total of 1800 were enrolled. Following a baseline survey, villages were randomized to a treatment or wait-list control group. Participants in treatment villages received training, start-up capital, and follow-up support. Participants, implementers, and data collectors were not blinded to treatment status. RESULTS: Villages were randomized to the treatment group (60 villages with 896 participants) or the wait-list control group (60 villages with 904 participants) with an allocation ration of 1:1. All clusters participated in the intervention and were included in the analysis. The intent-to-treat analysis included 860 treatment participants and 866 control participants (4.1% attrition). Sixteen months after the program, monthly cash earnings doubled from UGX 22 523 to 51 124, non-household and non-farm businesses doubled, and cash savings roughly quadrupled. There was no measurable effect on a locally derived measure of symptoms of depression. CONCLUSIONS: Despite finding large increases in business, income, and savings among the treatment group, we do not find support for an indirect effect of poverty alleviation on symptoms of depression.

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