Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 48
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Child Psychol Psychiatry ; 63(2): 152-164, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-33993507

RESUMEN

BACKGROUND: Postnatal maternal anxiety is common (estimates as high as 40% prevalence) and is associated with altered mother-infant interactions (e.g., reduced maternal emotional expression and engagement). Neural circuitry supporting infants' face and emotion processing develops in their first year. Thus, early exposure to maternal anxiety may impact infants' developing understanding of emotional displays. We examine whether maternal anxiety is associated with individual differences in typically developing infants' neural responses to emotional faces. METHODS: One hundred and forty two mother-infant dyads were assessed when infants were 5, 7, or 12 months old. Infants' electroencephalographic (EEG) data were recorded while passively viewing female happy, fearful, and angry faces. Three event-related potential (ERP) components, each linked to face and emotion processing, were evaluated: NC, N290, and P400. Infant ERP amplitude was related to concurrent maternal-report anxiety assessed with the Spielberger State-Trait Anxiety Inventory (Trait form). RESULTS: Greater maternal anxiety predicted more negative NC amplitude for happy and fearful faces in left and mid-central scalp regions, beyond covarying influences of maternal depression symptoms, infant negative emotionality, and infant age. CONCLUSIONS: Postnatal maternal anxiety is related to infants' neural processing of emotional expressions. Infants of mothers endorsing high trait anxiety may need additional attentional resources to process happy and fearful faces (expressions less likely experienced in mother-infant interactions). Future research should investigate mechanisms underlying this association, given possibilities include experiential, genetic, and prenatal factors.


Asunto(s)
Emociones , Expresión Facial , Ansiedad/psicología , Atención/fisiología , Emociones/fisiología , Potenciales Evocados/fisiología , Femenino , Humanos , Lactante
2.
BMC Pregnancy Childbirth ; 22(1): 885, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36447143

RESUMEN

BACKGROUND: There is a renewed call to address preventable foetal deaths in high-income countries, especially where progress has been slow. The Centers for Disease Control and Prevention released publicly, for the first time, the initiating cause and estimated timing of foetal deaths in 2014. The objective of this study is to describe risk and characteristics of antepartum versus intrapartum stillbirths in the U.S., and frequency of pathological examination to determine cause. METHODS: We conducted a cross-sectional study of singleton births (24-43 weeks) using 2014 U.S. Fetal Death and Natality data available from the National Center for Health Statistics. The primary outcome was timing of death (antepartum (n = 6200), intrapartum (n = 453), and unknown (n = 5403)). Risk factors of interest included maternal sociodemographic, behavioural, medical and obstetric factors, along with foetal sex. We estimated gestational week-specific stillbirth hazard, risk factors for intrapartum versus antepartum stillbirth using multivariable log-binomial regression models, conditional probabilities of intrapartum and antepartum stillbirth at each gestational week, and frequency of pathological examination by timing of death. RESULTS: The gestational age-specific stillbirth hazard was approximately 2 per 10,000 foetus-weeks among preterm gestations and > 3 per 10,000 foetus-weeks among term gestations. Both antepartum and intrapartum stillbirth risk increased in late-term and post-term gestations. The risk of intrapartum versus antepartum stillbirth was higher among those without a prior live birth, relative to those with at least one prior live birth (RR 1.32; 95% CI 1.08-1.61) and those with gestational hypertension, relative to those with no report of gestational hypertension (RR 1.47; 95% CI 1.09-1.96), and lower among Black, relative to white, individuals (RR 0.70; 95% CI 0.55-0.89). Pathological examination was not performed/planned in 25% of known antepartum stillbirths and 29% of known intrapartum stillbirths. CONCLUSION: These findings suggest greater stillbirth risk in the late-term and post-term periods. Primiparous mothers had greater risk of intrapartum than antepartum still birth, suggesting the need for intrapartum interventions for primiparous mothers in this phase of pregnancy to prevent some intrapartum foetal deaths. Efforts are needed to improve understanding, prevention and investigation of foetal deaths as well as improve stillbirth data quality and completeness in the United States.


Asunto(s)
Hipertensión Inducida en el Embarazo , Mortinato , Estados Unidos/epidemiología , Femenino , Embarazo , Recién Nacido , Humanos , Mortinato/epidemiología , Estudios Transversales , Factores Sexuales , Parto
3.
Infant Child Dev ; 29(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-32617081

RESUMEN

When children transition to school between the ages of 4 and 6 years, they must learn to control their attention and behavior to be successful. Concurrently, executive function (EF) is an important skill undergoing significant development in childhood. To understand changes occurring during this period, we examined the role of parenting in the development of children's EF from 4 to 6 years old. Participants were mother and child dyads (N = 151). Children completed cognitive tasks to assess overall EF at age 4 and age 6. At both time points, mothers and children completed interaction tasks which were videotaped and coded to assess various parenting dimensions. Results indicated that children with high EF at age 4 were more likely to have high EF at age 6. In addition, results suggested that higher levels of positive parenting across the transition to school promote stability of individual differences in EF.

4.
Dev Sci ; 22(3): e12758, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30276933

RESUMEN

In the present study we examined the neural correlates of facial emotion processing in the first year of life using ERP measures and cortical source analysis. EEG data were collected cross-sectionally from 5- (N = 49), 7- (N = 50), and 12-month-old (N = 51) infants while they were viewing images of angry, fearful, and happy faces. The N290 component was found to be larger in amplitude in response to fearful and happy than angry faces in all posterior clusters and showed largest response to fear than the other two emotions only over the right occipital area. The P400 and Nc components were found to be larger in amplitude in response to angry than happy and fearful faces over central and frontal scalp. Cortical source analysis of the N290 component revealed greater cortical activation in the right fusiform face area in response to fearful faces. This effect started to emerge at 5 months and became well established at 7 months, but it disappeared at 12 months. The P400 and Nc components were primarily localized to the PCC/Precuneus where heightened responses to angry faces were observed. The current results suggest the detection of a fearful face in infants' brain can happen shortly (~200-290 ms) after the stimulus onset, and this process may rely on the face network and develop substantially between 5 to 7 months of age. The current findings also suggest the differential processing of angry faces occurred later in the P400/Nc time window, which recruits the PCC/Precuneus and is associated with the allocation of infants' attention.


Asunto(s)
Atención/fisiología , Mapeo Encefálico/métodos , Emociones/fisiología , Potenciales Evocados/fisiología , Expresión Facial , Ira/fisiología , Corteza Cerebral/fisiología , Estudios Transversales , Miedo/fisiología , Femenino , Felicidad , Humanos , Lactante , Masculino
5.
J Biol Chem ; 291(39): 20574-87, 2016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27507812

RESUMEN

Allergic asthma is a chronic lung disease initiated and driven by Th2 cytokines IL-4/-13. In macrophages, IL-4/-13 bind IL-4 receptors, which signal through insulin receptor substrate (IRS)-2, inducing M2 macrophage differentiation. M2 macrophages correlate with disease severity and poor lung function, although the mechanisms that regulate M2 polarization are not understood. Following IL-4 exposure, suppressor of cytokine signaling (SOCS)1 is highly induced in human monocytes. We found that siRNA knockdown of SOCS1 prolonged IRS-2 tyrosine phosphorylation and enhanced M2 differentiation, although siRNA knockdown of SOCS3 did not affect either. By co-immunoprecipitation, we found that SOCS1 complexes with IRS-2 at baseline, and this association increased after IL-4 stimulation. Because SOCS1 is an E3 ubiquitin ligase, we examined the effect of proteasome inhibitors on IL-4-induced IRS-2 phosphorylation. Proteasomal inhibition prolonged IRS-2 tyrosine phosphorylation, increased ubiquitination of IRS-2, and enhanced M2 gene expression. siRNA knockdown of SOCS1 inhibited ubiquitin accumulation on IRS-2, although siRNA knockdown of SOCS3 had no effect on ubiquitination of IRS-2. Monocytes from healthy and allergic individuals revealed that SOCS1 is induced by IL-4 in healthy monocytes but not allergic cells, whereas SOCS3 is highly induced in allergic monocytes. Healthy monocytes displayed greater ubiquitination of IRS-2 and lower M2 polarization than allergic monocytes in response to IL-4 stimulation. Here, we identify SOCS1 as a key negative regulator of IL-4-induced IRS-2 signaling and M2 differentiation. Our findings provide novel insight into how dysregulated expression of SOCS increases IL-4 responses in allergic monocytes, and this may represent a new therapeutic avenue for managing allergic disease.


Asunto(s)
Hipersensibilidad/metabolismo , Proteínas Sustrato del Receptor de Insulina/metabolismo , Interleucina-4/metabolismo , Macrófagos/metabolismo , Monocitos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteína 1 Supresora de la Señalización de Citocinas/biosíntesis , Animales , Diferenciación Celular/genética , Femenino , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Hipersensibilidad/genética , Hipersensibilidad/patología , Proteínas Sustrato del Receptor de Insulina/genética , Interleucina-4/genética , Macrófagos/patología , Masculino , Ratones , Monocitos/patología , Fosforilación/genética , Complejo de la Endopetidasa Proteasomal/genética , Transducción de Señal/genética , Proteína 1 Supresora de la Señalización de Citocinas/genética , Tirosina/genética , Tirosina/metabolismo , Células U937 , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinación/genética
6.
Law Hum Behav ; 41(1): 55-67, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27977225

RESUMEN

Understanding the role that mental health issues play in justice-involved youth poses challenges for research, policy, and practice. While mental health problems are generally not risk factors for criminal behavior according to the risk-needs-responsivity (RNR) framework of correctional psychology practice, prevalence rates are very high and RNR principles suggest that mental health as a responsivity variable may moderate the success of interventions targeted to criminogenic needs. In this study we investigated the relationships among mental health status, criminogenic needs treatment, and recidivism in a sample of 232 youth referred for court-ordered assessments and followed through their community supervision sentence (probation). Youth with mental health needs were no more likely than youth without these needs to reoffend, regardless of whether those needs were treated. Youth who received mental health treatment also more frequently had their criminogenic needs matched across several domains, suggesting an association between mental health treatment and intermediate treatment targets. However, mental health did not moderate the effect of criminogenic needs treatment: youth who had a greater proportion of criminogenic needs targeted through appropriate services were less likely to reoffend, regardless of mental health status. Findings are consistent with the RNR stance that, within a correctional context in which the primary goal of intervention is preventing recidivism, treatment for mental health needs should be in addition to criminogenic needs treatment, not in replacement of it. They also point to the need for continued research to understand precisely how mental health treatment interacts with intervention targeting criminogenic needs. (PsycINFO Database Record


Asunto(s)
Delincuencia Juvenil/psicología , Delincuencia Juvenil/rehabilitación , Salud Mental , Adolescente , Niño , Femenino , Humanos , Entrevista Psicológica , Masculino , Adulto Joven
7.
Am J Physiol Lung Cell Mol Physiol ; 309(1): L27-36, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25957295

RESUMEN

Asthma development and pathogenesis are influenced by the interactions of airway epithelial cells and innate and adaptive immune cells in response to allergens. Oxidative stress is an important mediator of asthmatic phenotypes in these cell types. Nuclear erythroid 2-related factor 2 (Nrf2) is a redox-sensitive transcription factor that is the key regulator of the response to oxidative and environmental stress. We previously demonstrated that Nrf2-deficient mice have heightened susceptibility to asthma, including elevated oxidative stress, inflammation, mucus, and airway hyperresponsiveness (AHR) (Rangasamy T, Guo J, Mitzner WA, Roman J, Singh A, Fryer AD, Yamamoto M, Kensler TW, Tuder RM, Georas SN, Biswal S. J Exp Med 202: 47-59, 2005). Here we dissected the role of Nrf2 in lung epithelial cells and tested whether genetic or pharmacological activation of Nrf2 reduces allergic asthma in mice. Cell-specific activation of Nrf2 in club cells of the airway epithelium significantly reduced allergen-induced AHR, inflammation, mucus, Th2 cytokine secretion, oxidative stress, and airway leakiness and increased airway levels of tight junction proteins zonula occludens-1 and E-cadherin. In isolated airway epithelial cells, Nrf2 enhanced epithelial barrier function and increased localization of zonula occludens-1 to the cell surface. Pharmacological activation of Nrf2 by 2-trifluoromethyl-2'-methoxychalone during the allergen challenge was sufficient to reduce allergic inflammation and AHR. New therapeutic options are needed for asthma, and this study demonstrates that activation of Nrf2 in lung epithelial cells is a novel potential therapeutic target to reduce asthma susceptibility.


Asunto(s)
Asma/patología , Hiperreactividad Bronquial/patología , Factor 2 Relacionado con NF-E2/metabolismo , Uniones Estrechas/inmunología , Proteína de la Zonula Occludens-1/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Asma/inducido químicamente , Asma/inmunología , Cadherinas/metabolismo , Chalconas/farmacología , Citocinas/inmunología , Citocinas/metabolismo , Citoprotección , Proteínas del Citoesqueleto/genética , Células Epiteliales/metabolismo , Inflamación/inmunología , Proteína 1 Asociada A ECH Tipo Kelch , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 2 Relacionado con NF-E2/genética , Ovalbúmina , Estrés Oxidativo/inmunología , Mucosa Respiratoria/citología , Células Th2/inmunología
8.
Cytokine ; 75(1): 38-50, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26187331

RESUMEN

Interleukin (IL)-4 and IL-13 were discovered approximately 30years ago and were immediately linked to allergy and atopic diseases. Since then, new roles for IL-4 and IL-13 and their receptors in normal gestation, fetal development and neurological function and in the pathogenesis of cancer and fibrosis have been appreciated. Studying IL-4/-13 and their receptors has revealed important clues about cytokine biology and led to the development of numerous experimental therapeutics. Here we aim to highlight new discoveries and consolidate concepts in the field of IL-4 and IL-13 structure, receptor regulation, signaling and experimental therapeutics.


Asunto(s)
Regulación de la Expresión Génica , Subunidad alfa del Receptor de Interleucina-4/metabolismo , Receptores de Interleucina-13/metabolismo , Transducción de Señal , Animales , Encéfalo/metabolismo , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Citocinas/metabolismo , Humanos , Inflamación/metabolismo , Interleucina-13/metabolismo , Subunidad alfa1 del Receptor de Interleucina-13 , Interleucina-4/metabolismo , Subunidad alfa del Receptor de Interleucina-4/genética , Ratones , Fenotipo , Polimorfismo Genético , Receptores de Interleucina-13/genética
9.
Am J Respir Cell Mol Biol ; 50(3): 538-48, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24102120

RESUMEN

Approximately 3 billion people-half the worldwide population-are exposed to extremely high concentrations of household air pollution due to the burning of biomass fuels on inefficient cookstoves, accounting for 4 million annual deaths globally. Yet, our understanding of the pulmonary responses to household air pollution exposure and the underlying molecular and cellular events is limited. The two most prevalent biomass fuels in India are wood and cow dung, and typical 24-hour mean particulate matter (PM) concentrations in homes that use these fuels are 300 to 5,000 µg/m(3). We dissected the mechanisms of pulmonary responses in mice after acute or subchronic exposure to wood or cow dung PM collected from rural Indian homes during biomass cooking. Acute exposures resulted in robust proinflammatory cytokine production, neutrophilic inflammation, airway resistance, and hyperresponsiveness, all of which were significantly higher in mice exposed to PM from cow dung. On the contrary, subchronic exposures induced eosinophilic inflammation, PM-specific antibody responses, and alveolar destruction that was highest in wood PM-exposed mice. To understand the molecular pathways that trigger biomass PM-induced inflammation, we exposed Toll-like receptor (TLR)2-, TLR3-, TLR4-, TLR5-, and IL-1R-deficient mice to PM and found that IL-1R, TLR4, and TLR2 are the predominant receptors that elicit inflammatory responses via MyD88 in mice exposed to wood or cow dung PM. In conclusion, this study demonstrates that subchronic exposure to PM collected from households burning biomass fuel elicits a persistent pulmonary inflammation largely through activation of TLR and IL-1R pathways, which could increase the risk for chronic respiratory diseases.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Biomasa , Culinaria , Fuentes Generadoras de Energía , Heces , Vivienda , Pulmón/efectos de los fármacos , Neumonía/inducido químicamente , Madera/efectos adversos , Resistencia de las Vías Respiratorias/efectos de los fármacos , Animales , Hiperreactividad Bronquial/inducido químicamente , Hiperreactividad Bronquial/inmunología , Hiperreactividad Bronquial/fisiopatología , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Mediadores de Inflamación/metabolismo , Exposición por Inhalación/efectos adversos , Pulmón/inmunología , Pulmón/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/metabolismo , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Neumonía/inmunología , Neumonía/fisiopatología , Receptores Tipo I de Interleucina-1/deficiencia , Receptores Tipo I de Interleucina-1/genética , Factores de Tiempo , Receptor Toll-Like 2/deficiencia , Receptor Toll-Like 2/genética , Receptor Toll-Like 4/deficiencia , Receptor Toll-Like 4/genética
10.
Transplant Direct ; 10(4): e1610, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38481964

RESUMEN

Background: Immunosuppression therapy (IST) is required for allograft survival but can cause significant adverse effects. Donor-derived cell-free DNA (dd-cfDNA) is a validated noninvasive biomarker for active rejection in kidney transplant (KTx). Evidence supporting dd-cfDNA testing use in IST management is limited. Methods: In this single-center observational study, dd-cfDNA testing was performed in 21 KTx patients considered good candidates for mycophenolic acid (MPA) reduction. Patients with dd-cfDNA <1% at the first visit (enrollment) had their MPA dosage reduced; those with dd-cfDNA ≥1% had their MPA dosage maintained. Patients were monitored with dd-cfDNA for 6 additional visits. Results: Of 21 patients enrolled in the study, 17 were considered low risk for rejection by dd-cfDNA and underwent MPA reduction; 4 patients were considered high risk for rejection by dd-cfDNA and had their initial MPA dosage maintained. Of the 4 patients considered high risk for rejection by dd-cfDNA, 1 experienced chronic allograft nephropathy and graft loss, and another received an indication biopsy that showed no evidence of rejection. Of the 17 patients considered low risk for rejection by dd-cfDNA, none experienced allograft rejection. dd-cfDNA was used for surveillance in a 6-mo period following MPA reduction; no untoward results were noted. Conclusions: This proof-of-concept study reports the use of dd-cfDNA to directly inform IST management in a cohort of KTx who were candidates for IST reduction.

11.
Dev Cogn Neurosci ; 67: 101396, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38820695

RESUMEN

Electroencephalography (EEG) is an important tool in the field of developmental cognitive neuroscience for indexing neural activity. However, racial biases persist in EEG research that limit the utility of this tool. One bias comes from the structure of EEG nets/caps that do not facilitate equitable data collection across hair textures and types. Recent efforts have improved EEG net/cap design, but these solutions can be time-intensive, reduce sensor density, and are more difficult to implement in younger populations. The present study focused on testing EEG sensor net designs over infancy. Specifically, we compared EEG data quality and retention between two high-density saline-based EEG sensor net designs from the same company (Magstim EGI, Whitland, UK) within the same infants during a baseline EEG paradigm. We found that within infants, the tall sensor nets resulted in lower impedances during collection, including lower impedances in the key online reference electrode for those with greater hair heights and resulted in a greater number of usable EEG channels and data segments retained during pre-processing. These results suggest that along with other best practices, the modified tall sensor net design is useful for improving data quality and retention in infant participants with curly or tightly-coiled hair.


Asunto(s)
Electroencefalografía , Cabello , Humanos , Electroencefalografía/métodos , Lactante , Femenino , Masculino , Encéfalo/fisiología
12.
J Immunol ; 187(8): 4280-92, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21908731

RESUMEN

Immunopathology is a major cause of influenza-associated morbidity and mortality worldwide. However, the role and regulatory mechanisms of CD4 T cells in severe lung immunopathology following acute influenza infection are poorly understood. In this paper, we report that the emergence of immunopathogenic CD4 T cells is under the control of a transmembrane immunoadaptor DAP12 pathway during influenza infection. We find that the mice lacking DAP12 have unaltered viral clearance but easily succumb to influenza infection as a result of uncontrolled immunopathology. Such immunopathology is associated with markedly increased CD4 T cells displaying markedly increased cytotoxicity and Fas ligand expression. Furthermore, the immunopathogenic property of these CD4 T cells is transferrable. Thus, depletion of CD4 T cells or abrogation of Fas/Fas ligand signaling pathway improves survival and immunopathology. We further find that DAP12 expressed by dendritic cells plays an important role in controlling the immunopathogenic CD4 T cells during influenza infection. Our findings identify a novel pathway that controls the level of immune-pathogenic CD4 T cells during acute influenza infection.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/inmunología , Linfocitos T CD4-Positivos/inmunología , Subtipo H1N1 del Virus de la Influenza A , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/patología , Infecciones del Sistema Respiratorio/inmunología , Infecciones del Sistema Respiratorio/patología , Traslado Adoptivo , Animales , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/inmunología , Separación Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neumonía/inmunología , Neumonía/patología , Neumonía/virología , Infecciones del Sistema Respiratorio/virología , Transducción de Señal/inmunología
13.
Clin Immunol ; 144(1): 57-69, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22673491

RESUMEN

Influenza epidemics and pandemics cause significant morbidity and mortality worldwide associated with severe immunopathology in the lung, and the mechanisms of such immunopathogenesis still remain poorly understood. While human studies help to understand influenza immunopathology, they provide only limited mechanistic information. On the other hand, recent studies using experimental animal models have significantly enhanced our understanding of the complex mechanisms involved in the immunopathogenesis during primary influenza or influenza-associated bacterial superinfection. This includes the involvement of acute inflammatory responses (macrophages, neutrophils, dendritic cells, toll-like receptors, cytokines, chemokines), CD4 and CD8 T cells, tissue remodeling processes, and contribution of bacterial superinfection. In particular, progress has been made in uncoupling the mechanisms that are involved in both anti-viral host defense and in immunopathogenesis from those that solely contribute to lung immunopathology. Uncoupling such events will facilitate the discovery of new intervention strategies to treat pulmonary immunopathology associated with influenza infection.


Asunto(s)
Gripe Humana/inmunología , Animales , Infecciones Bacterianas/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Humanos , Inflamación/inmunología , Sobreinfección/inmunología
14.
Am J Pathol ; 178(4): 1622-34, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21406169

RESUMEN

The granuloma, a hallmark of host defense against pulmonary mycobacterial infection, has long been believed to be an active type 1 immune environment. However, the mechanisms regarding why granuloma fails to eliminate mycobacteria even in immune-competent hosts, have remained largely unclear. By using a model of pulmonary Mycobacterium bovis Bacillus Calmette-Guerin (BCG) infection, we have addressed this issue by comparing the immune responses within the airway luminal and granuloma compartments. We found that despite having a similar immune cellular profile to that in the airway lumen, the granuloma displayed severely suppressed type 1 immune cytokine but enhanced chemokine responses. Both antigen-presenting cells (APCs) and T cells in granuloma produced fewer type 1 immune molecules including tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and nitric oxide. As a result, the granuloma APCs developed a reduced capacity to phagocytose mycobacteria and to induce T-cell proliferation. To examine the molecular mechanisms, we compared the levels of immune suppressive cytokine IL-10 in the airway lumen and granuloma and found that both granuloma APCs and T cells produced much more IL-10. Thus, IL-10 deficiency restored type 1 immune activation within the granuloma while having a minimal effect within the airway lumen. Hence, our study provides the first experimental evidence that, contrary to the conventional belief, the BCG-induced lung granuloma represents a symbiotic host-microbe microenvironment characterized by suppressed type 1 immune activation.


Asunto(s)
Granuloma/microbiología , Interleucina-10/metabolismo , Mycobacterium bovis/metabolismo , Animales , Células Presentadoras de Antígenos/metabolismo , Vacuna BCG/metabolismo , Antígeno CD11b/biosíntesis , Antígeno CD11c/biosíntesis , Proliferación Celular , Femenino , Sistema Inmunológico , Interferón gamma/metabolismo , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico/metabolismo , Simbiosis , Linfocitos T/citología , Linfocitos T/microbiología , Factor de Necrosis Tumoral alfa/metabolismo
15.
J Immunol ; 184(4): 2048-56, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-20083661

RESUMEN

Influenza viral infection is well-known to predispose to subsequent bacterial superinfection in the lung but the mechanisms have remained poorly defined. We have established a murine model of heterologous infections by an H1N1 influenza virus and Staphylococcus aureus. We found that indeed prior influenza infection markedly increased the susceptibility of mice to secondary S. aureus superinfection. Severe sickness and heightened bacterial infection in flu and S. aureus dual-infected animals were associated with severe immunopathology in the lung. We further found that flu-experienced lungs had an impaired NK cell response in the airway to subsequent S. aureus bacterial infection. Thus, adoptive transfer of naive NK cells to the airway of prior flu-infected mice restored flu-impaired antibacterial host defense. We identified that TNF-alpha production of NK cells played an important role in NK cell-mediated antibacterial host defense as NK cells in flu-experienced lungs had reduced TNF-alpha expression and adoptive transfer of TNF-alpha-deficient NK cells to the airway of flu-infected mice failed to restore flu-impaired antibacterial host defense. Defected NK cell function was found to be an upstream mechanism of depressed antibacterial activities by alveolar macrophages as contrast to naive wild-type NK cells, the NK cells from flu-infected or TNF-alpha-deficient mice failed to enhance S. aureus phagocytosis by alveolar macrophages. Together, our study identifies the weakened NK cell response in the lung to be a novel critical mechanism for flu-mediated susceptibility to bacterial superinfection.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A/inmunología , Células Asesinas Naturales/inmunología , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/microbiología , Neumonía Bacteriana/inmunología , Neumonía Viral/inmunología , Infecciones Estafilocócicas/inmunología , Sobreinfección/inmunología , Animales , Susceptibilidad a Enfermedades/inmunología , Susceptibilidad a Enfermedades/patología , Femenino , Células Asesinas Naturales/microbiología , Células Asesinas Naturales/virología , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/microbiología , Macrófagos Alveolares/patología , Ratones , Ratones Endogámicos C57BL , Infecciones por Orthomyxoviridae/patología , Neumonía Bacteriana/patología , Neumonía Bacteriana/virología , Neumonía Viral/microbiología , Neumonía Viral/patología , Infecciones Estafilocócicas/patología , Infecciones Estafilocócicas/virología , Sobreinfección/microbiología , Sobreinfección/patología , Sobreinfección/virología
16.
Br J Dev Psychol ; 40(2): 271-286, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35175643

RESUMEN

Social interactions between parents and children are important for developing theory of mind, but these may be disrupted by aspects of the proximal home environment. The current study observed maternal sensitivity and its associations with child theory of mind and the housing environment (index by clutter and crowding) in a sample of mothers and their 3.5-year-old twins (N = 250 children). Maternal sensitivity and housing environment were measured from experimenter report and child theory of mind was measured through behavioural tasks. Results show that the association between maternal sensitivity and child theory of mind was moderated by the housing environment, where the positive associations between maternal sensitivity and child theory of mind were only observed at lower levels of clutter and crowding in the housing environment. Additional contextual variables and processes are discussed.


Asunto(s)
Teoría de la Mente , Niño , Preescolar , Aglomeración , Composición Familiar , Femenino , Humanos , Madres
17.
Transplant Proc ; 54(6): 1446-1454, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35618524

RESUMEN

BACKGROUND: Kidney transplant (KT) recipients are at high risk for developing severe COVID-19. Lowering immunosuppression levels in KT recipients with COVID-19 encourages native immune responses but can raise the risk of rejection. Donor-derived cell-free DNA (dd-cfDNA), reported as a fraction of total cfDNA, is a proven biomarker for KT rejection. Total cfDNA levels are elevated in patients with COVID-19, which may depress dd-cfDNA fractions, potentially leading to missed rejections. METHODS: A retrospective analysis of 29 KT recipients hospitalized with COVID-19 between April and November 2020 examined total and dd-cfDNA levels. Blood samples were collected after onset of COVID-19, with follow-up samples collected from a subset of patients, when infection had likely subsided. RESULTS: After COVID-19 diagnosis, the median total cfDNA level was elevated (7.9 multiples of median [MoM]). A significant decrease in total cfDNA levels was observed between the first and second time points (6.2 MoM, 1.0 MoM; P <001). A significant positive association was identified between total cfDNA levels and COVID-19 severity (P = .02; R2 = .19). Two patients with biopsy-proven acute cellular rejection had dd-cfDNA fractions below the 1% cutoff for rejection (0.20% and 0.78%), with elevated total cfDNA levels of 7.9 MoM and 41.8 MoM, respectively. CONCLUSIONS: In this preliminary study, total cfDNA levels were elevated in KT patients with COVID-19, subsiding after resolution of infection. High total cfDNA levels may confound dd-cfDNA results, leading to failure to identify rejection. Considering total cfDNA levels is important in interpretation of dd-cfDNA tests for assessment of rejection in KT patients with COVID-19 or other infection.


Asunto(s)
COVID-19 , Ácidos Nucleicos Libres de Células , Trasplante de Riñón , Biomarcadores , Prueba de COVID-19 , Rechazo de Injerto , Humanos , Trasplante de Riñón/efectos adversos , Estudios Retrospectivos , SARS-CoV-2 , Donantes de Tejidos
18.
J Neurointerv Surg ; 14(6): 623-627, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34433646

RESUMEN

BACKGROUND: Mobile stroke units (MSUs) performance dependability and diagnostic yield of 16-slice, ultra-fast CT with auto-injection angiography (CTA) of the aortic arch/neck/circle of Willis has not been previously reported. METHODS: We performed a prospective observational study of the first-of-its kind MSU equipped with high resolution, 16-slice CT with multiphasic CTA. Field CT/CTA was performed on all suspected stroke patients regardless of symptom severity or resolution. Performance dependability, efficiency and diagnostic yield over 365 days was quantified. RESULTS: 1031 MSU emergency activations occurred; of these, 629 (61%) were disregarded with unrelated diagnoses, and 402 patients transported: 245 (61%) ischemic or hemorrhagic stroke, 17 (4%) transient ischemic attack, 140 (35%) other neurologic emergencies. Total time from non-contrast CT/CTA start to images ready for viewing was 4.0 (IQR 3.5-4.5) min. Hemorrhagic stroke totaled 24 (10%): aneurysmal subarachnoid hemorrhage 3, hemorrhagic infarct 1, and 20 intraparenchymal hemorrhages (median intracerebral hemorrhage score was 2 (IQR 1-3), 4 (20%) spot sign positive). In 221 patients with ischemic stroke, 73 (33%) received alteplase with 31.5% treated within 60 min of onset. CTA revealed large vessel occlusion in 66 patients (30%) of which 9 (14%) were extracranial; 27 (41%) underwent thrombectomy with onset to puncture time averaging 141±90 min (median 112 (IQR 90-139) min) with full emergency department (ED) bypass. No imaging needed to be repeated for image quality; all patients were triaged correctly with no inter-hospital transfer required. CONCLUSIONS: MSU use of advanced imaging including multiphasic head/neck CTA is feasible, offers high LVO yield and enables full ED bypass.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular , Angiografía , Isquemia Encefálica/cirugía , Angiografía Cerebral , Angiografía por Tomografía Computarizada/métodos , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Tomografía Computarizada por Rayos X
19.
Am J Respir Crit Care Med ; 181(8): 862-72, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20019338

RESUMEN

RATIONALE: The airway luminal memory CD8 T cells induced by respiratory mucosal immunization in a murine model have been found to be critical to antituberculosis immunity. However, the mechanisms of their maintenance on airway mucosal surface still remain poorly understood. OBJECTIVES: Using a model of adenovirus-based intranasal immunization we investigated the immune property and the mechanisms of maintenance of airway luminal CD8 T cells. METHODS: Immune properties of airway luminal Mycobacterium tuberculosis antigen-specific CD8 T cells were examined. Proliferation of airway luminal CD8 T cells was determined by in vivo T cell-labeling techniques. The role of peripheral T cell recruitment in maintaining airway luminal CD8 T cells was investigated by blocking lymphocyte trafficking from lymphoid and peripheral tissues. The requirement of M. tuberculosis antigens for in situ T cell proliferation was evaluated using a T cell transfer approach. An airway M. tuberculosis challenge model was used to study the relationship between CD8 T cell-mediated protection and peripheral T cell recruitment. MEASUREMENTS AND MAIN RESULTS: Intranasal immunization leads to elicitation of persisting M. tuberculosis antigen-specific CD8 T cells in the airway lumen, which display an activated effector memory phenotype different from those in peripheral tissues. Airway luminal T cells continuously proliferate in an antigen-dependent manner, and can be maintained even in the absence of peripheral T cell recruitment. The lungs equipped with such CD8 T cells are protected from airway M. tuberculosis challenge independent of both peripheral T cell supply and CD4 T cells. CONCLUSIONS: Vaccine-inducible airway luminal antituberculosis memory CD8 T cells are self-renewable in an antigen-dependent manner, and can be maintained independent of peripheral T cell supply.


Asunto(s)
Bronquios/inmunología , Linfocitos T CD8-positivos/inmunología , Memoria Inmunológica/inmunología , Mucosa Respiratoria/inmunología , Vacunas contra la Tuberculosis/inmunología , Tuberculosis Pulmonar/prevención & control , Administración Intranasal , Traslado Adoptivo/métodos , Animales , Antígenos Bacterianos/efectos de los fármacos , Antígenos Bacterianos/inmunología , Bronquios/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Inmunización Secundaria , Memoria Inmunológica/efectos de los fármacos , Pulmón/efectos de los fármacos , Pulmón/inmunología , Ratones , Ratones Endogámicos BALB C , Mucosa Respiratoria/efectos de los fármacos , Tuberculosis Pulmonar/inmunología
20.
Soc Dev ; 30(3): 786-805, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34334970

RESUMEN

Parents' responses to children's negative emotional states play a key role in the socialization of emotion regulation skills in childhood. Much of the prior research on child ER has focused on early development using cross-sectional designs. The current study addresses these gaps by using a longitudinal design to examine individual differences of ER at two times points in middle childhood. We examined the development of children's ER by testing hypotheses about the interplay of parent response to emotions and household chaos in the prediction of individual differences in children's ER. Participants were the mothers of children at 6 and 9 years of age among 224 families in a socioeconomically diverse sample that was part of an ongoing longitudinal study. Mothers completed questionnaires regarding themselves, their children, and their home environment. Mothers' reports of better child ER at both time points were positively associated with mothers' more supportive responses and negatively associated with mothers' less non-supportive responses, as well as lower household chaos. Chaos statistically moderated the link between non-supportive parental responses to emotion and child ER, but only at 6 years of age. The strength of the link between child ER and non-supportive parental responses to emotions was strong only at lower levels of household chaos. At the beginning of middle childhood, family processes linking parent responses to child emotions and children's developing ER may not function at higher levels of household chaos.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA