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1.
Am J Respir Crit Care Med ; 209(11): 1360-1375, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271553

RESUMEN

Rationale: Chronic lung allograft dysfunction (CLAD) is the leading cause of death after lung transplant, and azithromycin has variable efficacy in CLAD. The lung microbiome is a risk factor for developing CLAD, but the relationship between lung dysbiosis, pulmonary inflammation, and allograft dysfunction remains poorly understood. Whether lung microbiota predict outcomes or modify treatment response after CLAD is unknown. Objectives: To determine whether lung microbiota predict post-CLAD outcomes and clinical response to azithromycin. Methods: Retrospective cohort study using acellular BAL fluid prospectively collected from recipients of lung transplant within 90 days of CLAD onset. Lung microbiota were characterized using 16S rRNA gene sequencing and droplet digital PCR. In two additional cohorts, causal relationships of dysbiosis and inflammation were evaluated by comparing lung microbiota with CLAD-associated cytokines and measuring ex vivo P. aeruginosa growth in sterilized BAL fluid. Measurements and Main Results: Patients with higher bacterial burden had shorter post-CLAD survival, independent of CLAD phenotype, azithromycin treatment, and relevant covariates. Azithromycin treatment improved survival in patients with high bacterial burden but had negligible impact on patients with low or moderate burden. Lung bacterial burden was positively associated with CLAD-associated cytokines, and ex vivo growth of P. aeruginosa was augmented in BAL fluid from transplant recipients with CLAD. Conclusions: In recipients of lung transplants with chronic rejection, increased lung bacterial burden is an independent risk factor for mortality and predicts clinical response to azithromycin. Lung bacterial dysbiosis is associated with alveolar inflammation and may be promoted by underlying lung allograft dysfunction.


Asunto(s)
Azitromicina , Rechazo de Injerto , Trasplante de Pulmón , Microbiota , Humanos , Azitromicina/uso terapéutico , Masculino , Femenino , Persona de Mediana Edad , Rechazo de Injerto/microbiología , Rechazo de Injerto/prevención & control , Estudios Retrospectivos , Adulto , Microbiota/efectos de los fármacos , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Pulmón/microbiología , Enfermedad Crónica , Receptores de Trasplantes/estadística & datos numéricos , Anciano , Disbiosis , Estudios de Cohortes , Líquido del Lavado Bronquioalveolar/microbiología
2.
Am J Physiol Lung Cell Mol Physiol ; 326(1): L39-L51, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37933452

RESUMEN

Idiopathic pulmonary fibrosis (IPF) is marked by unremitting matrix deposition and architectural distortion. Multiple profibrotic pathways contribute to the persistent activation of mesenchymal cells (MCs) in fibrosis, highlighting the need to identify and target common signaling pathways. The transcription factor nuclear factor of activated T cells 1 (NFAT1) lies downstream of second messenger calcium signaling and has been recently shown to regulate key profibrotic mediator autotaxin (ATX) in lung MCs. Herein, we investigate the role of NFAT1 in regulating fibroproliferative responses during the development of lung fibrosis. Nfat1-/--deficient mice subjected to bleomycin injury demonstrated improved survival and protection from lung fibrosis and collagen deposition as compared with bleomycin-injured wild-type (WT) mice. Chimera mice, generated by reconstituting bone marrow cells from WT or Nfat1-/- mice into irradiated WT mice (WT→WT and Nfat1-/-→WT), demonstrated no difference in bleomycin-induced fibrosis, suggesting immune influx-independent fibroprotection in Nfat1-/- mice. Examination of lung tissue and flow sorted lineageneg/platelet-derived growth factor receptor alpha (PDGFRα)pos MCs demonstrated decreased MC numbers, proliferation [↓ cyclin D1 and 5-ethynyl-2'-deoxyuridine (EdU) incorporation], myofibroblast differentiation [↓ α-smooth muscle actin (α-SMA)], and survival (↓ Birc5) in Nfat1-/- mice. Nfat1 deficiency abrogated ATX expression in response to bleomycin in vivo and MCs derived from Nfat1-/- mice demonstrated decreased ATX expression and migration in vitro. Human IPF MCs demonstrated constitutive NFAT1 activation, and regulation of ATX in these cells by NFAT1 was confirmed using pharmacological and genetic inhibition. Our findings identify NFAT1 as a critical mediator of profibrotic processes, contributing to dysregulated lung remodeling and suggest its targeting in MCs as a potential therapeutic strategy in IPF.NEW & NOTEWORTHY Idiopathic pulmonary fibrosis (IPF) is a fatal disease with hallmarks of fibroblastic foci and exuberant matrix deposition, unknown etiology, and ineffective therapies. Several profibrotic/proinflammatory pathways are implicated in accelerating tissue remodeling toward a honeycombed end-stage disease. NFAT1 is a transcriptional factor activated in IPF tissues. Nfat1-deficient mice subjected to chronic injury are protected against fibrosis independent of immune influxes, with suppression of profibrotic mesenchymal phenotypes including proliferation, differentiation, resistance to apoptosis, and autotaxin-related migration.


Asunto(s)
Fibrosis Pulmonar Idiopática , Pulmón , Animales , Humanos , Ratones , Bleomicina/farmacología , Diferenciación Celular/genética , Fibroblastos/metabolismo , Fibrosis Pulmonar Idiopática/inducido químicamente , Fibrosis Pulmonar Idiopática/genética , Fibrosis Pulmonar Idiopática/metabolismo , Pulmón/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal
3.
Am J Transplant ; 21(7): 2360-2371, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33249747

RESUMEN

Histopathologic examination of lungs afflicted by chronic lung allograft dysfunction (CLAD) consistently shows both mononuclear cell (MNC) inflammation and mesenchymal cell (MC) fibroproliferation. We hypothesize that interleukin 6 (IL-6) trans-signaling may be a critical mediator of MNC-MC crosstalk and necessary for the pathogenesis of CLAD. Bronchoalveolar lavage (BAL) fluid obtained after the diagnosis of CLAD has approximately twofold higher IL-6 and soluble IL-6 receptor (sIL-6R) levels compared to matched pre-CLAD samples. Human BAL-derived MCs do not respond to treatment with IL-6 alone but have rapid and prolonged JAK2-mediated STAT3 Tyr705 phosphorylation when exposed to the combination of IL-6 and sIL-6R. STAT3 phosphorylation within MCs upregulates numerous genes causing increased invasion and fibrotic differentiation. MNC, a key source of both IL-6 and sIL-6R, produce minimal amounts of these proteins at baseline but significantly upregulate production when cocultured with MCs. Finally, the use of an IL-6 deficient recipient in a murine orthotopic transplant model of CLAD reduces allograft fibrosis by over 50%. Taken together these results support a mechanism where infiltrating MNCs are stimulated by resident MCs to release large quantities of IL-6 and sIL-6R which then feedback onto the MCs to increase invasion and fibrotic differentiation.


Asunto(s)
Interleucina-6 , Trasplante de Pulmón , Aloinjertos , Animales , Fibrosis , Humanos , Pulmón/patología , Trasplante de Pulmón/efectos adversos , Ratones , Receptores de Interleucina-6
4.
Acad Psychiatry ; 43(2): 167-170, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29644602

RESUMEN

OBJECTIVE: This study sought to screen for the burden of work-related posttraumatic stress disorder (PTSD) symptoms in internal medicine residents. METHODS: A cross-sectional survey of internal medicine residents from three academic institutions was conducted using the PCL-5 screening tool. RESULTS: Off all residents surveyed, 5.2% screened positive for PTSD symptoms (N = 194). 86.1% of all trainees identified stressors during training. Positive PTSD screens were significantly higher in PGY3 residents (X2 = 15.24, p = 0.0005). Of all PGY3 residents, 9.8% (N = 4) and 14.6% (N = 6) of residents screened positive for PTSD symptoms based on absolute and cluster score criteria, respectively. Verbal/physical assault by patients/families/colleagues were triggers for the most cases of positive screens. CONCLUSIONS: Self-reported stressors are highly prevalent in internal medicine trainees. Verbal/physical assault by patients and families appear to be the triggering event for most positive screens. These observations will help with future study designs to quantify the burden of work related PTSD in internal medicine trainee physicians so that appropriate supportive measures can be provided.


Asunto(s)
Medicina Interna/educación , Internado y Residencia , Trastornos por Estrés Postraumático/diagnóstico , Estudios Transversales , Educación de Postgrado en Medicina , Humanos , Prevalencia , Trastornos por Estrés Postraumático/epidemiología , Estrés Psicológico/psicología , Encuestas y Cuestionarios
5.
Proc Natl Acad Sci U S A ; 112(51): E7138-47, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26553986

RESUMEN

Acute amphetamine (AMPH) exposure elevates extracellular dopamine through a variety of mechanisms that include inhibition of dopamine reuptake, depletion of vesicular stores, and facilitation of dopamine efflux across the plasma membrane. Recent work has shown that the DAT substrate AMPH, unlike cocaine and other nontransported blockers, can also stimulate endocytosis of the plasma membrane dopamine transporter (DAT). Here, we show that when AMPH enters the cytoplasm it rapidly stimulates DAT internalization through a dynamin-dependent, clathrin-independent process. This effect, which can be observed in transfected cells, cultured dopamine neurons, and midbrain slices, is mediated by activation of the small GTPase RhoA. Inhibition of RhoA activity with C3 exotoxin or a dominant-negative RhoA blocks AMPH-induced DAT internalization. These actions depend on AMPH entry into the cell and are blocked by the DAT inhibitor cocaine. AMPH also stimulates cAMP accumulation and PKA-dependent inactivation of RhoA, thus providing a mechanism whereby PKA- and RhoA-dependent signaling pathways can interact to regulate the timing and robustness of AMPH's effects on DAT internalization. Consistent with this model, the activation of D1/D5 receptors that couple to PKA in dopamine neurons antagonizes RhoA activation, DAT internalization, and hyperlocomotion observed in mice after AMPH treatment. These observations support the existence of an unanticipated intracellular target that mediates the effects of AMPH on RhoA and cAMP signaling and suggest new pathways to target to disrupt AMPH action.


Asunto(s)
Anfetamina/farmacología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Proteínas de Unión al GTP rho/metabolismo , 2,3,4,5-Tetrahidro-7,8-dihidroxi-1-fenil-1H-3-benzazepina/farmacología , Animales , Conducta Animal/efectos de los fármacos , Conducta Animal/fisiología , Transporte Biológico Activo/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología , Clatrina/metabolismo , Cocaína/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Agonistas de Dopamina/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Endocitosis/efectos de los fármacos , Locomoción/efectos de los fármacos , Locomoción/fisiología , Masculino , Mesencéfalo/efectos de los fármacos , Mesencéfalo/metabolismo , Ratones , Transducción de Señal/efectos de los fármacos , Proteínas de Unión al GTP rac/metabolismo
6.
J Neurosci ; 35(13): 5260-70, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25834051

RESUMEN

The gene for EAAT2, the major astrocytic glutamate transporter, generates two carrier isoforms (EAAT2a and EAAT2b) that vary at their C termini as a consequence of alternative RNA splicing. The EAAT2b cytoplasmic C terminus contains a postsynaptic density-95/Discs large/zona occludens-1 (PDZ) ligand, which is absent in EAAT2a. To understand how the distinct C termini might affect transporter trafficking and surface localization, we generated Madin-Darby canine kidney (MDCK) cells that stably express EGFP-EAAT2a or EGFP-EAAT2b and found robust basolateral membrane expression of the EAAT2b isoform. In contrast, EAAT2a displayed a predominant distribution within intracellular vesicle compartments, constitutively cycling to and from the membrane. Addition of the PDZ ligand to EAAT2a as well as its deletion from EAAT2b confirmed the importance of the motif for cell-surface localization. Using EAAT2 constructs with an extracellular biotin acceptor tag to directly assess surface proteins, we observed significant PDZ ligand-dependent EAAT2b surface expression in cultured astrocytes, consistent with observations in cell lines. Discs large homolog 1 (DLG1; SAP97), a PDZ protein prominent in both astrocytes and MDCK cells, colocalized and coimmunoprecipitated with EAAT2b. shRNA knockdown of DLG1 expression decreased surface EAAT2b in both MDCK cells and cultured astrocytes, suggesting that the DLG scaffolding protein stabilizes EAAT2b at the surface. DLG1 can be phosphorylated by Ca(2+)/calmodulin-dependent protein kinase (CaMKII), resulting in disruption of its PDZ-mediated interaction. In murine astrocytes and acute brain slices, activation of CaMKII decreases EAAT2b surface expression but does not alter the distribution of EAAT2a. These data indicate that the surface expression and function of EAAT2b can be rapidly modulated through the disruption of its interaction with DLG1 by CaMKII activation.


Asunto(s)
Astrocitos/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Transportador 2 de Aminoácidos Excitadores/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Animales , Encéfalo/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Vesículas Citoplasmáticas/metabolismo , Homólogo 1 de la Proteína Discs Large , Perros , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Mutación , Dominios PDZ/genética , Isoformas de Proteínas/metabolismo , ARN Interferente Pequeño/farmacología , Proteínas Asociadas a SAP90-PSD95
8.
Nat Chem Biol ; 7(5): 278-84, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21445058

RESUMEN

The generation of cAMP by G protein-coupled receptors (GPCRs) and its termination are currently thought to occur exclusively at the plasma membrane of cells. Under existing models of receptor regulation, this signal is primarily restricted by desensitization of the receptors through their binding to ß-arrestins. However, this paradigm is not consistent with recent observations that the parathyroid hormone receptor type 1 (PTHR) continues to stimulate cAMP production even after receptor internalization, as ß-arrestins are known to rapidly bind and internalize activated PTHR. Here we show that binding to ß-arrestin1 prolongs rather than terminates the generation of cAMP by PTHR, and that cAMP generation correlates with the persistence of arrestin-receptor complexes on endosomes. PTHR signaling is instead turned off by the retromer complex, which regulates the movement of internalized receptor from endosomes to the Golgi apparatus. Thus, binding by the retromer complex regulates the sustained generation of cAMP triggered by an internalized GPCR.


Asunto(s)
AMP Cíclico/metabolismo , Endosomas/metabolismo , Aparato de Golgi/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Arrestinas/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Células HEK293 , Humanos , Modelos Biológicos , Receptor de Hormona Paratiroídea Tipo 1/genética , Transducción de Señal , Factores de Tiempo , beta-Arrestinas
9.
Nitric Oxide ; 31: 9-19, 2013 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-23474170

RESUMEN

iNOS localizes to both the cytosol and peroxisomes in hepatocytes in vitro and in vivo. The structural determinants for iNOS localization are not known. One plausible mechanism for iNOS localization to the peroxisome is through the interaction with peroxisomal import proteins PEX5 or PEX7. siRNA knockdown of PEX7 reduced iNOS colocalization with the peroxisomal protein PMP70. Proteomic studies using MALDI-MS identified iNOS association with the 50-kD ezrin binding PDZ protein (EBP50). Confocal microscopy studies and immunoelectron microscopy confirmed iNOS association with EBP50, with greatest colocalization occurring at 8h of cytokine exposure. EBP50 associated with peroxisomes in a PEX5 and PEX7-dependent manner. iNOS localization to peroxisomes was contingent on EBP50 expression in LPS-treated mice. Thus, iNOS targeting to peroxisomes in hepatocytes involves interaction with PEX7 and EBP50. The targeting of iNOS protein to the peroxisome may shift the balance of metabolic processes that rely on heme proteins susceptible to modification by radical oxygen and nitrogen radicals.


Asunto(s)
Hepatocitos/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Peroxisomas/metabolismo , Fosfoproteínas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Animales , Hepatocitos/química , Hepatocitos/enzimología , Hígado/química , Hígado/enzimología , Hígado/metabolismo , Ratones , Ratones Noqueados , Microscopía Confocal , Microscopía Fluorescente , Receptor de la Señal 2 de Direccionamiento al Peroxisoma , Fosfoproteínas/genética , ARN Interferente Pequeño/genética , Receptores Citoplasmáticos y Nucleares/genética , Transducción de Señal , Intercambiadores de Sodio-Hidrógeno/genética
10.
Lancet Respir Med ; 9(6): 601-612, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33460570

RESUMEN

BACKGROUND: Alterations in the respiratory microbiome are common in chronic lung diseases, correlate with decreased lung function, and have been associated with disease progression. The clinical significance of changes in the respiratory microbiome after lung transplant, specifically those related to development of chronic lung allograft dysfunction (CLAD), are unknown. The aim of this study was to evaluate the effect of lung microbiome characteristics in healthy lung transplant recipients on subsequent CLAD-free survival. METHODS: We prospectively studied a cohort of lung transplant recipients at the University of Michigan (Ann Arbor, MI, USA). We analysed characteristics of the respiratory microbiome in acellular bronchoalveolar lavage fluid (BALF) collected from asymptomatic patients during per-protocol surveillance bronchoscopy 1 year after lung transplantation. For our primary endpoint, we evaluated a composite of development of CLAD or death at 500 days after the 1-year surveillance bronchoscopy. Our primary microbiome predictor variables were bacterial DNA burden (total 16S rRNA gene copies per mL of BALF, quantified via droplet digital PCR) and bacterial community composition (determined by bacterial 16S rRNA gene sequencing). Patients' lung function was followed serially at least every 3 months by spirometry, and CLAD was diagnosed according to International Society of Heart and Lung Transplant 2019 guidelines. FINDINGS: We analysed BALF from 134 patients, collected during 1-year post-transplant surveillance bronchoscopy between Oct 21, 2005, and Aug 25, 2017. Within 500 days of follow-up from the time of BALF sampling, 24 (18%) patients developed CLAD, five (4%) died before confirmed development of CLAD, and 105 (78%) patients remained CLAD-free with complete follow-up. Lung bacterial burden was predictive of CLAD development or death within 500 days of the surveillance bronchoscopy, after controlling for demographic and clinical factors, including immunosuppression and bacterial culture results, in a multivariable survival model. This relationship was evident when burden was analysed as a continuous variable (per log10 increase in burden, HR 2·49 [95% CI 1·38-4·48], p=0·0024) or by tertiles (middle vs lowest bacterial burden tertile, HR 4·94 [1·25-19·42], p=0·022; and highest vs lowest, HR 10·56 [2·53-44·08], p=0·0012). In patients who developed CLAD or died, composition of the lung bacterial community significantly differed to that in patients who survived and remained CLAD-free (on permutational multivariate analysis of variance, p=0·047 at the taxonomic level of family), although differences in community composition were associated with bacterial burden. No individual bacterial taxa were definitively associated with CLAD development or death. INTERPRETATION: Among asymptomatic lung transplant recipients at 1-year post-transplant, increased lung bacterial burden is predictive of chronic rejection and death. The lung microbiome represents an understudied and potentially modifiable risk factor for lung allograft dysfunction. FUNDING: US National Institutes of Health, Cystic Fibrosis Foundation, Brian and Mary Campbell and Elizabeth Campbell Carr research gift fund.


Asunto(s)
Rechazo de Injerto/diagnóstico , Rechazo de Injerto/microbiología , Trasplante de Pulmón , Pulmón/microbiología , Microbiota , Receptores de Trasplantes/estadística & datos numéricos , Enfermedad Crónica , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
11.
J Clin Invest ; 131(21)2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34546975

RESUMEN

In this study, we demonstrate that forkhead box F1 (FOXF1), a mesenchymal transcriptional factor essential for lung development, was retained in a topographically distinct mesenchymal stromal cell population along the bronchovascular space in an adult lung and identify this distinct subset of collagen-expressing cells as key players in lung allograft remodeling and fibrosis. Using Foxf1-tdTomato BAC (Foxf1-tdTomato) and Foxf1-tdTomato Col1a1-GFP mice, we show that Lin-Foxf1+ cells encompassed the stem cell antigen 1+CD34+ (Sca1+CD34+) subset of collagen 1-expressing mesenchymal cells (MCs) with a capacity to generate CFU and lung epithelial organoids. Histologically, FOXF1-expressing MCs formed a 3D network along the conducting airways; FOXF1 was noted to be conspicuously absent in MCs in the alveolar compartment. Bulk and single-cell RNA-Seq confirmed distinct transcriptional signatures of Foxf1+ and Foxf1- MCs, with Foxf1-expressing cells delineated by their high expression of the transcription factor glioma-associated oncogene 1 (Gli1) and low expression of integrin α8 (Itga), versus other collagen-expressing MCs. FOXF1+Gli1+ MCs showed proximity to Sonic hedgehog-expressing (Shh-expressing) bronchial epithelium, and mesenchymal expression of Foxf1 and Gli1 was found to be dependent on paracrine Shh signaling in epithelial organoids. Using a murine lung transplant model, we show dysregulation of epithelial-mesenchymal SHH/GLI1/FOXF1 crosstalk and expansion of this specific peribronchial MC population in chronically rejecting fibrotic lung allografts.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Rechazo de Injerto/metabolismo , Trasplante de Pulmón , Células Madre Mesenquimatosas/metabolismo , Alveolos Pulmonares/metabolismo , Fibrosis Pulmonar/metabolismo , Aloinjertos , Animales , Enfermedad Crónica , Factores de Transcripción Forkhead/genética , Rechazo de Injerto/genética , Rechazo de Injerto/patología , Células Madre Mesenquimatosas/patología , Ratones , Ratones Transgénicos , Alveolos Pulmonares/patología , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/genética , Fibrosis Pulmonar/patología
12.
J Heart Lung Transplant ; 39(8): 815-823, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32360292

RESUMEN

BACKGROUND: Chronic lung allograft dysfunction (CLAD), the primary cause of poor outcome after lung transplantation, arises from fibrotic remodeling of the allograft and presents as diverse clinical phenotypes with variable courses. Here, we investigate whether bronchoalveolar lavage (BAL) mesenchymal cell activity at CLAD onset can inform regarding disease phenotype, progression, and survival. METHODS: Mesenchymal cell colony-forming units (CFUs) were measured in BAL obtained at CLAD onset (n = 77) and CLAD-free time post-transplant matched controls (n = 77). CFU counts were compared using Wilcoxon's rank-sum test. Cox proportional hazards and restricted means models were utilized to investigate post-CLAD survival. RESULTS: Higher mesenchymal CFU counts were noted in BAL at the time of CLAD onset than in CLAD-free controls. Patients with restrictive allograft syndrome had higher BAL mesenchymal CFU count at CLAD onset than patients with bronchiolitis obliterans syndrome (p = 0.011). Patients with high mesenchymal CFU counts (≥10) at CLAD onset had worse outcomes than those with low (<10) CFU counts, with shorter average survival (2.64 years vs 4.25 years; p = 0.027) and shorter progression-free survival, defined as time to developing either CLAD Stage 3 or death (0.97 years vs 2.70 years; p < 0.001). High CFU count remained predictive of decreased overall survival and progression-free survival after accounting for the CLAD phenotype and other clinical factors in multivariable analysis. CONCLUSIONS: Fulminant fibroproliferation with higher mesenchymal CFU counts in BAL is noted in restrictive allograft syndrome and is independently associated with poor survival after CLAD onset.


Asunto(s)
Bronquiolitis Obliterante/cirugía , Líquido del Lavado Bronquioalveolar/citología , Trasplante de Pulmón , Células Madre Mesenquimatosas/citología , Disfunción Primaria del Injerto/etiología , Adulto , Aloinjertos , Broncoscopía , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Disfunción Primaria del Injerto/diagnóstico , Disfunción Primaria del Injerto/mortalidad , Estudios Prospectivos , Tasa de Supervivencia/tendencias , Estados Unidos/epidemiología
13.
Sci Rep ; 10(1): 21231, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-33277571

RESUMEN

Forkhead box F1 (FOXF1) is a lung embryonic mesenchyme-associated transcription factor that demonstrates persistent expression into adulthood in mesenchymal stromal cells. However, its biologic function in human adult lung-resident mesenchymal stromal cells (LR-MSCs) remain to be elucidated. Here, we demonstrate that FOXF1 expression acts as a restraint on the migratory function of LR-MSCs via its role as a novel transcriptional repressor of autocrine motility-stimulating factor Autotaxin (ATX). Fibrotic human LR-MSCs demonstrated lower expression of FOXF1 mRNA and protein, compared to non-fibrotic controls. RNAi-mediated FOXF1 silencing in LR-MSCs was associated with upregulation of key genes regulating proliferation, migration, and inflammatory responses and significantly higher migration were confirmed in FOXF1-silenced LR-MSCs by Boyden chamber. ATX is a secreted lysophospholipase D largely responsible for extracellular lysophosphatidic acid (LPA) production, and was among the top ten upregulated genes upon Affymetrix analysis. FOXF1-silenced LR-MSCs demonstrated increased ATX activity, while mFoxf1 overexpression diminished ATX expression and activity. The FOXF1 silencing-induced increase in LR-MSC migration was abrogated by genetic and pharmacologic targeting of ATX and LPA1 receptor. Chromatin immunoprecipitation analyses identified three putative FOXF1 binding sites in the 1.5 kb ATX promoter which demonstrated transcriptional repression of ATX expression. Together these findings identify FOXF1 as a novel transcriptional repressor of ATX and demonstrate that loss of FOXF1 promotes LR-MSC migration via the ATX/LPA/LPA1 signaling axis.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Pulmón/metabolismo , Lisofosfolípidos/metabolismo , Células Madre Mesenquimatosas/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Receptores del Ácido Lisofosfatídico/metabolismo , Animales , Sitios de Unión/genética , Movimiento Celular/genética , Proliferación Celular/genética , Células Cultivadas , Inmunoprecipitación de Cromatina , Citocinas/metabolismo , Factores de Transcripción Forkhead/genética , Ontología de Genes , Silenciador del Gen , Humanos , Pulmón/citología , Ratones , Hidrolasas Diéster Fosfóricas/genética , Regiones Promotoras Genéticas , Interferencia de ARN , Transducción de Señal/genética , Activación Transcripcional/genética , Regulación hacia Arriba
14.
JCI Insight ; 5(23)2020 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-33268593

RESUMEN

Understanding the distinct pathogenic mechanisms that culminate in allograft fibrosis and chronic graft failure is key in improving outcomes after solid organ transplantation. Here, we describe an F1 → parent orthotopic lung transplant model of restrictive allograft syndrome (RAS), a particularly fulminant form of chronic lung allograft dysfunction (CLAD), and identify a requisite pathogenic role for humoral immune responses in development of RAS. B6D2F1/J (H2-b/d) donor lungs transplanted into the parent C57BL/6J (H2-b) recipients demonstrated a spectrum of histopathologic changes, ranging from lymphocytic infiltration, fibrinous exudates, and endothelialitis to peribronchial and pleuroparenchymal fibrosis, similar to those noted in the human RAS lungs. Gene expression profiling revealed differential humoral immune cell activation as a key feature of the RAS murine model, with significant B cell and plasma cell infiltration noted in the RAS lung allografts. B6D2F1/J lung allografts transplanted into µMt-/- (mature B cell deficient) or activation-induced cytidine deaminase (AID)/secretory µ-chain (µs) double-KO (AID-/-µs-/-) C57BL/6J mice demonstrated significantly decreased allograft fibrosis, indicating a key role for antibody secretion by B cells in mediating RAS pathology. Our study suggests that skewing of immune responses determines the diverse allograft remodeling patterns and highlights the need to develop targeted therapies for specific CLAD phenotypes.


Asunto(s)
Aloinjertos/inmunología , Aloinjertos/patología , Inmunidad Humoral/inmunología , Animales , Fibrosis , Rechazo de Injerto/inmunología , Pulmón/patología , Trasplante de Pulmón/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Trasplante de Órganos , Fenotipo
15.
PLoS One ; 13(1): e0191040, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29324807

RESUMEN

It is increasingly evident that cytokines and growth factors produced in the decidua play a pivotal role in the regulation of the local immune microenvironment and the establishment of pregnancy. One of the major growth factors produced in the decidua is vascular endothelial growth factor (VEGF), which acts not only on endothelial cells, but also on multiple other cell types, including macrophages. We sought to determine whether decidua-derived VEGF affects macrophage recruitment and polarization using human endometrial/decidual tissue samples, primary human endometrial stromal cells (ESCs), and the human monocyte cell line THP1. In situ hybridization was used for assessment of local VEGF expression and immunohistochemistry was used for identification and localization of CD68-positive endometrial macrophages. Macrophage migration in culture was assessed using a transwell migration assay, and the various M1/M2 phenotypic markers and VEGF expression were assessed using quantitative real-time PCR (qRT-PCR). We found dramatic increases in both VEGF levels and macrophage numbers in the decidua during early pregnancy compared to the secretory phase endometrium (non-pregnant), with a significant increase in M2 macrophage markers, suggesting that M2 is the predominant macrophage phenotype in the decidua. However, decidual samples from preeclamptic pregnancies showed a significant shift in macrophage phenotype markers, with upregulation of M1 and downregulation of M2 markers. In THP1 cultures, VEGF treatment significantly enhanced macrophage migration and induced M1 macrophages to shift to an M2 phenotype. Moreover, treatment with conditioned media from decidualized ESCs induced changes in macrophage migration and polarization similar to that of VEGF treatment. These effects were abrogated by the addition of a potent VEGF inhibitor. Together these results suggest that decidual VEGF plays a significant role in macrophage recruitment and M2 polarization, and that inhibition of VEGF signaling may contribute to the shift in macrophage polarity observed in different pregnancy disorders, including preeclampsia.


Asunto(s)
Polaridad Celular , Decidua/citología , Macrófagos/citología , Factor A de Crecimiento Endotelial Vascular/fisiología , Adulto , Línea Celular , Femenino , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa
16.
Cardiovasc Revasc Med ; 18(5): 344-348, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28285786

RESUMEN

AIM: The purpose of this study is to determine whether ad hoc (same session) percutaneous coronary intervention, and staged (multiple session) percutaneous coronary intervention (PCI) have different renal outcomes. METHODS AND RESULTS: This is a retrospective cohort study that compares the maximal decline in glomerular filtration rate (GFR) at various times points (3-6days, 1-4weeks, 4-12weeks) after either ad hoc or staged PCI. 115 patients undergoing staged PCI and 115 matched ad hoc PCI controls were included in the study. They were equivalent in baseline GFR, left ventricular ejection fraction and intra-procedural volume status based on LVEDP. The group undergoing staged PCI had greater cumulative fluoroscopy time, SYNTAX score and number of stents placed. Staged PCIs used less contrast per catheterization (155.0±5.6mL) but higher cumulative contrast dose (326.6±14.0mL) compared to ad hoc PCIs (193.4±7.2mL). Following intervention, there was a progressive decline in renal function that did not significantly differ between the ad hoc and staged groups. In the subgroup of patients with initial GFR ≤60cm3/min, staged PCI was associated with 2.6-fold greater decline in renal function 4-12weeks after the procedure compared to ad hoc. A propensity match analysis performed in patients with GFR ≤60cm3/min confirmed worse renal function in the staged group at 4-12weeks. CONCLUSIONS: Staged PCI exposes patients to greater cumulative contrast agent loads. The decline in renal function observed in both groups did not differ significantly, however worse renal outcomes were observed in the staged PCI group with baseline GFR ≤60cm3/min.


Asunto(s)
Enfermedad de la Arteria Coronaria/cirugía , Intervención Coronaria Percutánea , Insuficiencia Renal/terapia , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón/métodos , Medios de Contraste/efectos adversos , Femenino , Tasa de Filtración Glomerular/fisiología , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
17.
ACG Case Rep J ; 3(2): 121-3, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26958566

RESUMEN

We present a patient with hepatitis C virus (HCV) and cirrhosis who was treated with eltrombopag for idiopathic thrombocytopenic purpura and was incidentally found to have a right atrial thrombus with extension into the left internal jugular vein. Eltrombopag was discontinued and the patient was treated with thrombectomy and anticoagulation. Given the proposed use of eltrombopag in HCV-associated thrombocytopenia, we advise caution when treating cirrhotics who are at higher intrinsic risk of thrombosis.

18.
PLoS One ; 11(4): e0153144, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27055101

RESUMEN

Directional flow of the cerebrospinal fluid requires coordinated movement of the motile cilia of the ependymal epithelium that lines the cerebral ventricles. Here we report that mice lacking the Na+/H+ Exchanger Regulatory Factor 1 (NHERF1/Slc9a3r1, also known as EBP50) develop profound communicating hydrocephalus associated with fewer and disorganized ependymal cilia. Knockdown of NHERF1/slc9a3r1 in zebrafish embryos also causes severe hydrocephalus of the hindbrain and impaired ciliogenesis in the otic vesicle. Ultrastructural analysis did not reveal defects in the shape or organization of individual cilia. Similar phenotypes have been described in animals with deficiencies in Wnt signaling and the Planar Cell Polarity (PCP) pathway. We show that NHERF1 binds the PCP core genes Frizzled (Fzd) and Vangl. We further show that NHERF1 assembles a ternary complex with Fzd4 and Vangl2 and promotes translocation of Vangl2 to the plasma membrane, in particular to the apical surface of ependymal cells. Taken together, these results strongly support an important role for NHERF1 in the regulation of PCP signaling and the development of functional motile cilia.


Asunto(s)
Cilios/ultraestructura , Hidrocefalia/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/metabolismo , Animales , Células CHO , Polaridad Celular , Cilios/fisiología , Cricetulus , Técnicas de Silenciamiento del Gen , Hidrocefalia/veterinaria , Ratones , Fosfoproteínas/química , Intercambiadores de Sodio-Hidrógeno/química , Vía de Señalización Wnt , Pez Cebra
19.
Int J Cardiol ; 222: 313-318, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27500756

RESUMEN

UNLABELLED: Socioeconomic factors, including social support, may partially explain why African Americans (AA) have the highest prevalence of heart failure and with worse outcomes compared to other races. AA are more likely to be hospitalized and readmitted for heart failure and have higher mortality. The purpose of this study is to determine whether the social factors of marital status and living condition affect readmission rates and all-cause mortality following hospitalization for acute decompensated heart failure (ADHF) in AA patients. METHODS: Medical records from 611 AA admitted to Einstein Medical Center Philadelphia from January, 2011 to February, 2013 for ADHF were reviewed. Patient demographics including living condition (nursing home residents, living with family or living alone) and marital status (married or non-married -including single, divorced, separated and widowed) were correlated with all-cause mortality and readmission rates. RESULTS: In this cohort (53% male, mean age 65±15, mean ejection fraction 32±16%) 25% (n=152) of subjects were unmarried. Unmarried patients had significantly higher 30-day readmission rates (16% vs. 6% p=0.0002) and higher 1-year mortality (17% vs. 11% p=0.047) compared with married patients. Fifty percent (n=303) of subjects were living with family members, while 40% (n=242) and 11% (n=66) were living alone or in a nursing facility, respectively. Patients living with family members had significantly lower 30-day readmission rates when compared with those living alone or in a nursing facility (7% vs 21% vs. 18% p=<0.0001). Furthermore, they had the lowest 1-year mortality (14% vs 32% for nursing facility patients and 17% for those living alone (p=0.0007). After controlling for traditional risk factors (age, gender, body mass index, peak troponin I, left ventricular ejection fraction, B-type natriuretic peptide, hypertension, diabetes mellitus, hyperlipidemia, and coronary artery disease), being married was an indpendent predictor of 1-year mortality (OR 0.50 p=0.019) and living alone for 30-day readmission (OR 2.86 p=<0.001). CONCLUSION: The socioeconomic factors of marital status and living condition significantly correlated with mortality and 30-day readmission rate in AA heart failure patients. Specifically, being married and living with family independently predict lower mortality and fewer readmissions. Surprisingly, living in a nursing facility was associated with significantly higher mortality than living alone or with family.


Asunto(s)
Negro o Afroamericano , Insuficiencia Cardíaca/mortalidad , Estado Civil , Readmisión del Paciente/tendencias , Instituciones de Cuidados Especializados de Enfermería/tendencias , Condiciones Sociales/tendencias , Anciano , Anciano de 80 o más Años , Femenino , Insuficiencia Cardíaca/economía , Humanos , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , Readmisión del Paciente/economía , Valor Predictivo de las Pruebas , Instituciones de Cuidados Especializados de Enfermería/economía , Condiciones Sociales/economía , Factores Socioeconómicos
20.
J Pain Symptom Manage ; 50(6): 882-6.e2, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26303186

RESUMEN

BACKGROUND: Patients with end-stage liver disease have a predictable and progressive decline in their quality of life because of physical symptoms and psychological distress. Early palliative care intervention (EPCI) correlates with better symptom control and mood. We aimed to improve symptomatology and mood in liver transplant candidates by implementing a longitudinal multidisciplinary EPCI. MEASURES: Depression level and symptom burden were assessed with Center for Epidemiological Studies Depression Scale and a modified liver-specific Edmonton Symptom Assessment System scale. INTERVENTION: All patients referred for liver transplant evaluation between July 2013 and May 2014 were scheduled for EPCI. OUTCOMES: After EPCI, 50% of moderate-to-severe symptoms improved (P < 0.05), and 43% of patients showed improvement in clinically significant depressive symptoms (P = 0.003). Notably, patients with more symptoms showed a greater improvement in Center for Epidemiological Studies Depression Scale scores (P = 0.001). CONCLUSIONS/LESSONS LEARNED: Implementation of EPCI improved symptom burden and mood in end-stage liver disease patients awaiting transplant.


Asunto(s)
Enfermedad Hepática en Estado Terminal/terapia , Trasplante de Hígado , Cuidados Paliativos/métodos , Cuidados Preoperatorios/métodos , Afecto , Costo de Enfermedad , Depresión , Enfermedad Hepática en Estado Terminal/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento
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