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1.
Nat Immunol ; 22(3): 381-390, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33589816

RESUMEN

The integrin α4ß7 selectively regulates lymphocyte trafficking and adhesion in the gut and gut-associated lymphoid tissue (GALT). Here, we describe unexpected involvement of the tyrosine phosphatase Shp1 and the B cell lectin CD22 (Siglec-2) in the regulation of α4ß7 surface expression and gut immunity. Shp1 selectively inhibited ß7 endocytosis, enhancing surface α4ß7 display and lymphocyte homing to GALT. In B cells, CD22 associated in a sialic acid-dependent manner with integrin ß7 on the cell surface to target intracellular Shp1 to ß7. Shp1 restrained plasma membrane ß7 phosphorylation and inhibited ß7 endocytosis without affecting ß1 integrin. B cells with reduced Shp1 activity, lacking CD22 or expressing CD22 with mutated Shp1-binding or carbohydrate-binding domains displayed parallel reductions in surface α4ß7 and in homing to GALT. Consistent with the specialized role of α4ß7 in intestinal immunity, CD22 deficiency selectively inhibited intestinal antibody and pathogen responses.


Asunto(s)
Linfocitos B/enzimología , Inmunidad Mucosa , Cadenas beta de Integrinas/metabolismo , Integrinas/metabolismo , Mucosa Intestinal/enzimología , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Lectina 2 Similar a Ig de Unión al Ácido Siálico/metabolismo , Animales , Linfocitos B/inmunología , Linfocitos B/virología , Quimiotaxis de Leucocito , Modelos Animales de Enfermedad , Endocitosis , Femenino , Cadenas beta de Integrinas/inmunología , Integrinas/inmunología , Mucosa Intestinal/inmunología , Mucosa Intestinal/virología , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 6/deficiencia , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Rotavirus/inmunología , Rotavirus/patogenicidad , Infecciones por Rotavirus/genética , Infecciones por Rotavirus/inmunología , Infecciones por Rotavirus/metabolismo , Lectina 2 Similar a Ig de Unión al Ácido Siálico/deficiencia , Lectina 2 Similar a Ig de Unión al Ácido Siálico/genética , Transducción de Señal , Técnicas de Cultivo de Tejidos
2.
Immunity ; 51(3): 561-572.e5, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31402260

RESUMEN

Lymphatic vessels form a critical component in the regulation of human health and disease. While their functional significance is increasingly being recognized, the comprehensive heterogeneity of lymphatics remains uncharacterized. Here, we report the profiling of 33,000 lymphatic endothelial cells (LECs) in human lymph nodes (LNs) by single-cell RNA sequencing. Unbiased clustering revealed six major types of human LECs. LECs lining the subcapsular sinus (SCS) of LNs abundantly expressed neutrophil chemoattractants, whereas LECs lining the medullary sinus (MS) expressed a C-type lectin CD209. Binding of a carbohydrate Lewis X (CD15) to CD209 mediated neutrophil binding to the MS. The neutrophil-selective homing by MS LECs may retain neutrophils in the LN medulla and allow lymph-borne pathogens to clear, preventing their spread through LNs in humans. Our study provides a comprehensive characterization of LEC heterogeneity and unveils a previously undefined role for medullary LECs in human immunity.


Asunto(s)
Células Endoteliales/inmunología , Neutrófilos/inmunología , Animales , Moléculas de Adhesión Celular/inmunología , Células Cultivadas , Humanos , Lectinas Tipo C/inmunología , Antígeno Lewis X/inmunología , Ganglios Linfáticos/inmunología , Vasos Linfáticos/inmunología , Ratones Endogámicos C57BL , Receptores de Superficie Celular/inmunología , Encuestas y Cuestionarios
3.
Nat Immunol ; 16(2): 207-213, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25531831

RESUMEN

Lymphocyte recruitment maintains intestinal immune homeostasis but also contributes to inflammation. The orphan chemoattractant receptor GPR15 mediates regulatory T cell homing and immunosuppression in the mouse colon. We show that GPR15 is also expressed by mouse TH17 and TH1 effector cells and is required for colitis in a model that depends on the trafficking of these cells to the colon. In humans GPR15 is expressed by effector cells, including pathogenic TH2 cells in ulcerative colitis, but is expressed poorly or not at all by colon regulatory T (Treg) cells. The TH2 transcriptional activator GATA-3 and the Treg-associated transcriptional repressor FOXP3 robustly bind human, but not mouse, GPR15 enhancer sequences, correlating with receptor expression. Our results highlight species differences in GPR15 regulation and suggest it as a potential therapeutic target for colitis.


Asunto(s)
Colitis/fisiopatología , Colon/fisiopatología , Regulación de la Expresión Génica , Receptores Acoplados a Proteínas G/metabolismo , Receptores Mensajeros de Linfocitos/metabolismo , Receptores de Péptidos/metabolismo , Animales , Células Cultivadas , Colitis/inmunología , Colon/inmunología , Modelos Animales de Enfermedad , Elementos de Facilitación Genéticos/genética , Factores de Transcripción Forkhead/metabolismo , Técnicas de Inactivación de Genes , Humanos , Ratones , Unión Proteica , Receptores Acoplados a Proteínas G/genética , Receptores de Péptidos/genética , Especificidad de la Especie
4.
Nat Immunol ; 15(10): 982-95, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25173345

RESUMEN

Lymphocytes are recruited from blood by high-endothelial venules (HEVs). We performed transcriptomic analyses and identified molecular signatures that distinguish HEVs from capillary endothelium and that define tissue-specific HEV specialization. Capillaries expressed gene programs for vascular development. HEV-expressed genes showed enrichment for genes encoding molecules involved in immunological defense and lymphocyte migration. We identify capillary and HEV markers and candidate mechanisms for regulated recruitment of lymphocytes, including a lymph node HEV-selective transmembrane mucin; transcriptional control of functionally specialized carbohydrate ligands for lymphocyte L-selectin; HEV expression of molecules for transendothelial migration; and metabolic programs for lipid mediators of lymphocyte motility and chemotaxis. We also elucidate a carbohydrate-recognition pathway that targets B cells to intestinal lymphoid tissues, defining CD22 as a lectin-homing receptor for mucosal HEVs.


Asunto(s)
Capilares/metabolismo , Endotelio/metabolismo , Perfilación de la Expresión Génica , Linfocitos/metabolismo , Tejido Linfoide/irrigación sanguínea , Vénulas/metabolismo , Animales , Movimiento Celular/genética , Células Endoteliales/metabolismo , Endotelio/citología , Femenino , Citometría de Flujo , Ontología de Genes , Ganglios Linfáticos/irrigación sanguínea , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Microscopía Confocal , Análisis de Secuencia por Matrices de Oligonucleótidos
5.
Nat Immunol ; 15(1): 98-108, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24292363

RESUMEN

Dendritic cells (DCs) that orchestrate mucosal immunity have been studied in mice. Here we characterized human gut DC populations and defined their relationship to previously studied human and mouse DCs. CD103(+)Sirpα(-) DCs were related to human blood CD141(+) DCs and to mouse intestinal CD103(+)CD11b(-) DCs and expressed markers of cross-presenting DCs. CD103(+)Sirpα(+) DCs aligned with human blood CD1c(+) DCs and mouse intestinal CD103(+)CD11b(+) DCs and supported the induction of regulatory T cells. Both CD103(+) DC subsets induced the TH17 subset of helper T cells, while CD103(-)Sirpα(+) DCs induced the TH1 subset of helper T cells. Comparative analysis of transcriptomes revealed conserved transcriptional programs among CD103(+) DC subsets and identified a selective role for the transcriptional repressors Bcl-6 and Blimp-1 in the specification of CD103(+)CD11b(-) DCs and intestinal CD103(+)CD11b(+) DCs, respectively. Our results highlight evolutionarily conserved and divergent programming of intestinal DCs.


Asunto(s)
Diferenciación Celular/inmunología , Células Dendríticas/inmunología , Mucosa Intestinal/inmunología , Transcriptoma/inmunología , Animales , Antígenos CD/inmunología , Antígenos CD/metabolismo , Antígenos CD1/inmunología , Antígenos CD1/metabolismo , Antígeno CD11b/inmunología , Antígeno CD11b/metabolismo , Diferenciación Celular/genética , Células Cultivadas , Análisis por Conglomerados , Reactividad Cruzada/genética , Reactividad Cruzada/inmunología , Células Dendríticas/metabolismo , Citometría de Flujo , Glicoproteínas/inmunología , Glicoproteínas/metabolismo , Humanos , Cadenas alfa de Integrinas/inmunología , Cadenas alfa de Integrinas/metabolismo , Integrinas/genética , Integrinas/inmunología , Ratones , Ratones Noqueados , Ratones Transgénicos , Microscopía Confocal , Análisis de Secuencia por Matrices de Oligonucleótidos , Receptores de Quimiocina/genética , Receptores de Quimiocina/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Transcriptoma/genética
6.
Am J Transplant ; 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38527588

RESUMEN

The first-generation Molecular Microscope (MMDx) system for heart transplant endomyocardial biopsies used expression of rejection-associated transcripts (RATs) to diagnose not only T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR) but also acute injury. However, the ideal system should detect rejection without being influenced by injury, to permit analysis of the relationship between rejection and parenchymal injury. To achieve this, we developed a new rejection classification in an expanded cohort of 3230 biopsies: 1641 from INTERHEART (ClinicalTrials.gov NCT02670408), plus 1589 service biopsies added to improve the power of the machine learning algorithms. The new system used 6 rejection classifiers instead of RATs and generated 7 rejection archetypes: No rejection, 48%; Minor, 24%; TCMR1, 2.3%; TCMR2, 2.7%; TCMR/mixed, 2.7%; early-stage ABMR, 3.9%; and fully developed ABMR, 16%. Using rejection classifiers eliminated cross-reactions with acute injury, permitting separate assessment of rejection and injury. TCMR was associated with severe-recent injury and late atrophy-fibrosis and rarely had normal parenchyma. ABMR was better tolerated, seldom producing severe injury, but in later biopsies was often associated with atrophy-fibrosis, indicating long-term risk. Graft survival and left ventricular ejection fraction were reduced not only in hearts with TCMR but also in hearts with severe-recent injury and atrophy-fibrosis, even without rejection.

7.
Development ; 148(20)2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34528674

RESUMEN

Specialized stromal cells occupy and help define B- and T-cell domains, which are crucial for proper functioning of our immune system. Signaling through lymphotoxin and TNF receptors is crucial for the development of different stromal subsets, which are thought to arise from a common precursor. However, mechanisms that control the selective generation of the different stromal phenotypes are not known. Using in vitro cultures of embryonic mouse stromal cells, we show that retinoic acid-mediated signaling is important for the differentiation of precursors towards the Cxcl13pos follicular dendritic cell (FDC) lineage, and also blocks lymphotoxin-mediated Ccl19pos fibroblastic reticular cell lineage differentiation. Accordingly, at the day of birth we observe the presence of Cxcl13posCcl19neg/low and Cxcl13neg/lowCcl19pos cells within neonatal lymph nodes. Furthermore, ablation of retinoic acid receptor signaling in stromal precursors early after birth reduces Cxcl13 expression, and complete blockade of retinoic acid signaling prevents the formation of FDC networks in lymph nodes.


Asunto(s)
Células Dendríticas Foliculares/metabolismo , Células Dendríticas Foliculares/fisiología , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/fisiología , Transducción de Señal/fisiología , Tretinoina/metabolismo , Animales , Diferenciación Celular/fisiología , Linaje de la Célula/fisiología , Ratones , Ratones Endogámicos C57BL , Células del Estroma/metabolismo , Células del Estroma/fisiología
8.
J Vasc Interv Radiol ; 35(3): 362-369, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38123126

RESUMEN

PURPOSE: To determine time to occlusion and procedure costs of embolization of pulmonary arteriovenous malformations (PAVMs) using a polytetrafluoroethylene-covered microplug compared with embolization using detachable coils. MATERIALS AND METHODS: In this prospective study, 37 patients (mean age, 39.1 years [SD ± 17.6]) with 82 PAVMs underwent embolization with microplug or detachable coils between April 2019 and January 2023. Technical success, procedure time intervals, and costs were analyzed. RESULTS: In 37 patients, 82 PAVMs and 101 feeding arteries were successfully treated (microplug, 64; microplug + another device, 5; detachable coils alone, 32). Time from embolic device inserted into the catheter to device deployed and time to occlusion differed significantly between microplug and detachable coil cohorts (P < .0001 for both). Embolization with ≥1 microplug had a significantly shorter occlusion time than embolization with detachable coils (median, 10.0 minutes saved per feeding artery) (P < .0001). Compared with detachable coil embolization, microplug embolization saved a median of 9.0 minutes per feeding artery (P < .0001) and reduced room cost by a median of $429 per feeding artery (P < .0001). Device costs per feeding artery did not differ significantly between microplug ($2,790) and detachable coil embolization ($3,147) (P = .87). CONCLUSIONS: Compared with coils, microplugs had an equally high technical success rate but significant time to occlusion and room costs savings per feeding artery. Total room cost and device cost together did not differ significantly between microplugs and coils. Microplugs may be considered technically effective and at least cost-neutral for PAVM embolization where clinically appropriate.


Asunto(s)
Fístula Arteriovenosa , Malformaciones Arteriovenosas , Embolización Terapéutica , Arteria Pulmonar/anomalías , Venas Pulmonares , Venas Pulmonares/anomalías , Humanos , Adulto , Estudios Prospectivos , Politetrafluoroetileno , Malformaciones Arteriovenosas/diagnóstico por imagen , Malformaciones Arteriovenosas/terapia , Fístula Arteriovenosa/terapia , Embolización Terapéutica/métodos , Arteria Pulmonar/diagnóstico por imagen , Venas Pulmonares/diagnóstico por imagen , Resultado del Tratamiento
9.
Nature ; 559(7714): 356-362, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29973725

RESUMEN

Arteries and veins are specified by antagonistic transcriptional programs. However, during development and regeneration, new arteries can arise from pre-existing veins through a poorly understood process of cell fate conversion. Here, using single-cell RNA sequencing and mouse genetics, we show that vein cells of the developing heart undergo an early cell fate switch to create a pre-artery population that subsequently builds coronary arteries. Vein cells underwent a gradual and simultaneous switch from venous to arterial fate before a subset of cells crossed a transcriptional threshold into the pre-artery state. Before the onset of coronary blood flow, pre-artery cells appeared in the immature vessel plexus, expressed mature artery markers, and decreased cell cycling. The vein-specifying transcription factor COUP-TF2 (also known as NR2F2) prevented plexus cells from overcoming the pre-artery threshold by inducing cell cycle genes. Thus, vein-derived coronary arteries are built by pre-artery cells that can differentiate independently of blood flow upon the release of inhibition mediated by COUP-TF2 and cell cycle factors.


Asunto(s)
Arterias/citología , Vasos Coronarios/citología , Análisis de la Célula Individual , Células Madre/citología , Células Madre/metabolismo , Venas/citología , Animales , Arterias/metabolismo , Factor de Transcripción COUP II/metabolismo , Ciclo Celular/genética , Diferenciación Celular , Linaje de la Célula , Vasos Coronarios/metabolismo , Femenino , Masculino , Ratones , Análisis de Secuencia de ARN , Venas/metabolismo
10.
Mol Ther ; 31(10): 2887-2900, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37641406

RESUMEN

The recruitment of cells with effector functions into the tumor microenvironment holds potential for delaying cancer progression. We show that subsets of human CD28-effector CD8 T cells, CCR7- CD45RO+ effector memory, and CCR7- CD45RO- effector memory RA phenotypes, express the chemerin receptor CMKLR1 and bind chemerin via the receptor. CMKLR1-expressing human CD8 effector memory T cells present gene, protein, and cytotoxic features of NK cells. Active chemerin promotes chemotaxis of CMKLR1-expressing CD8 effector memory cells and triggers activation of the α4ß1 integrin. In an experimental prostate tumor mouse model, chemerin expression is downregulated in the tumor microenvironment, which is associated with few tumor-infiltrating CD8+ T cells, while forced overexpression of chemerin by mouse prostate cancer cells leads to an accumulation of intra-tumor CD8+ T cells. Furthermore, α4 integrin blockade abrogated the chemerin-dependent recruitment of CD8+ T effector memory cells into implanted prostate tumors in vivo. The results identify a role for chemerin:CMKLR1 in defining a specialized NK-like CD8 T cell, and suggest the use of chemerin-dependent modalities to target effector CMKLR1-expressing T cells to the tumor microenvironment for immunotherapeutic purposes.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Humanos , Animales , Ratones , Linfocitos T CD8-positivos/metabolismo , Receptores CCR7/metabolismo , Subgrupos de Linfocitos T/metabolismo , Células Asesinas Naturales/metabolismo , Neoplasias/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Microambiente Tumoral , Péptidos y Proteínas de Señalización Intercelular/metabolismo
11.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34452999

RESUMEN

ZAP-70 is required for the initiation of T cell receptor (TCR) signaling, and Ssu72 is a phosphatase that regulates RNA polymerase II activity in the nucleus. However, the mechanism by which ZAP-70 regulates the fine-tuning of TCR signaling remains elusive. Here, we found that Ssu72 contributed to the fine-tuning of TCR signaling by acting as tyrosine phosphatase for ZAP-70. Affinity purification-mass spectrometry and an in vitro assay demonstrated specific interaction between Ssu72 and ZAP-70 in T cells. Upon TCR stimulation, Ssu72-deficient T cells increased the phosphorylation of ZAP-70 and downstream molecules and exhibited hyperresponsiveness, which was restored by reducing ZAP-70 phosphorylation. In vitro assay demonstrated that recombinant Ssu72 reduced tyrosine phosphorylation of ZAP-70 via phosphatase activity. Cd4-CreSsu72fl/fl mice showed a defect in the thymic development of invariant natural killer T cells and reductions in CD4+ and CD8+ T cell numbers in the periphery but more CD44hiCD62Llo memory T cells and fewer CD44loCD62Lhi naïve T cells, compared with wild-type mice. Furthermore, Cd4-CreSsu72fl/fl mice developed spontaneous inflammation at 6 mo. In conclusion, Ssu72 phosphatase regulates the fine-tuning of TCR signaling by binding to ZAP-70 and regulating its tyrosine phosphorylation, thereby preventing spontaneous inflammation.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Inflamación/prevención & control , Células T de Memoria/inmunología , Fosfoproteínas Fosfatasas/fisiología , Receptores de Antígenos de Linfocitos T/metabolismo , Proteína Tirosina Quinasa ZAP-70/metabolismo , Animales , Comunicación Celular , Inflamación/etiología , Inflamación/metabolismo , Inflamación/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Proteína Tirosina Quinasa ZAP-70/genética
12.
Curr Opin Organ Transplant ; 29(1): 50-55, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37991086

RESUMEN

PURPOSE OF REVIEW: Liver transplant is a widely accepted therapy for end-stage liver disease. With advances in our understanding of transplant, candidates are increasingly older with more cardiac comorbidities. Cardiovascular disease also represents a leading cause of morbidity and mortality posttransplant. RECENT FINDINGS: Preoperative cardiac risk stratification and treatment may improve short-term and long-term outcomes after liver transplant. Importantly, the appropriate frequency of surveillance has not been defined. Optimal timing of cardiac intervention in end-stage liver disease is likewise uncertain. SUMMARY: The approach to risk stratification of cardiovascular disease in end-stage liver disease is outlined, incorporating the AHA/ACC scientific statement on evaluation of cardiac disease in transplant candidates and more recent expert consensus documents. Further study is needed to clarify the ideal timing and approach for cardiovascular interventions.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad Hepática en Estado Terminal , Cardiopatías , Trasplante de Hígado , Humanos , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Trasplante de Hígado/efectos adversos , Corazón , Factores de Riesgo
13.
Cancer ; 129(22): 3595-3602, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37432072

RESUMEN

BACKGROUND: There are few assessments evaluating associations between birth defects with neural crest cell developmental origins (BDNCOs) and embryonal tumors, which are characterized by undifferentiated cells having a molecular profile similar to neural crest cells. The effect of BDNCOs on embryonal tumors was estimated to explore potential shared etiologic pathways and genetic origins. METHODS: With the use of a multistate, registry-linkage cohort study, BDNCO-embryonal tumor associations were evaluated by generating hazard ratios (HRs) and 95% confidence intervals (CIs) with Cox regression models. BDNCOs consisted of ear, face, and neck defects, Hirschsprung disease, and a selection of congenital heart defects. Embryonal tumors included neuroblastoma, nephroblastoma, and hepatoblastoma. Potential HR modification (HRM) was investigated by infant sex, maternal race/ethnicity, maternal age, and maternal education. RESULTS: The risk of embryonal tumors among those with BDNCOs was 0.09% (co-occurring n = 105) compared to 0.03% (95% CI, 0.03%-0.04%) among those without a birth defect. Children with BDNCOs were 4.2 times (95% CI, 3.5-5.1 times) as likely to be diagnosed with an embryonal tumor compared to children born without a birth defect. BDNCOs were strongly associated with hepatoblastoma (HR, 16.1; 95% CI, 11.3-22.9), and the HRs for neuroblastoma (3.1; 95% CI, 2.3-4.2) and nephroblastoma (2.9; 95% CI, 1.9-4.4) were elevated. There was no notable HRM by the aforementioned factors. CONCLUSIONS: Children with BDNCOs are more likely to develop embryonal tumors compared to children without a birth defect. Disruptions of shared developmental pathways may contribute to both phenotypes, which could inform future genomic assessments and cancer surveillance strategies of these conditions.


Asunto(s)
Hepatoblastoma , Neoplasias Renales , Neoplasias Hepáticas , Neuroblastoma , Tumor de Wilms , Lactante , Niño , Humanos , Cresta Neural , Estudios de Cohortes , Hepatoblastoma/epidemiología , Hepatoblastoma/genética , Tumor de Wilms/epidemiología , Tumor de Wilms/genética , Neuroblastoma/epidemiología , Neuroblastoma/genética , Factores de Riesgo
14.
NMR Biomed ; 36(6): e4963, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37211348

RESUMEN

The article from this special issue was previously published in NMR In Biomedicine , Volume 35, Issue 9, 2022. For completeness we are including the title page of the article below. The full text of the article can be read in Issue 35:9 on Wiley Online Library: https://doi.org/10.1002/nbm.4757.


Asunto(s)
Imagen por Resonancia Magnética , Protones , Humanos , Animales , Aminas/química , Técnicas de Cultivo de Célula , Células HEK293 , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen
15.
J Gen Intern Med ; 38(15): 3414-3423, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37580638

RESUMEN

BACKGROUND: Broader primary care practice range of services (ROS), defined as the diversity of professional services delivered, is associated with lower utilization. ROS provided by individual primary care physicians (PCPs) varies considerably with unclear implications for patients. OBJECTIVES: Create a PCP-ROS measure covering six categories of outpatient services, including expanded codes for mental health counseling services and point of care ultrasound (POCUS) technology in physician offices. Determine whether PCP-ROS is associated with total Medicare expenditures, inpatient admissions, acute hospital utilization (AHU), and emergency department (ED) visits. Examine physician and practice characteristics associated with PCP-ROS. DESIGN: Retrospective cohort study. PARTICIPANTS: 4,569,711 Medicare fee-for-service beneficiaries and 27,008 PCPs observed during the evaluation of the Comprehensive Primary Care Plus (CPC +) initiative. MEASUREMENTS: PCP-ROS, hospitalizations, AHU (includes observation stays as well as inpatient admissions), ED visits, and total Medicare expenditures. RESULTS: Physicians varied substantially in the range of services provided. Broader PCP-ROS was significantly, independently associated with 1 - 3% lower Medicare expenditures (p ≤ 0.01), inpatient admissions (p ≤ 0.027), AHU (p ≤ 0.025), and ED visit rates (p ≤ 0.000). PCP-ROS score was associated with improved patient outcomes, independent of physician provision of procedures (such as laceration repair or skin excisions). Physicians in practice sites affiliated with a hospital or health system had narrower PCP-ROS than independent physicians by 0.3 to 0.4 (p < 0.001). Internal medicine specialty was associated with narrower PCP-ROS than family medicine by 0.3 (p < 0.001). CONCLUSIONS: Patients cared for by primary care physicians who provide a broader range of services subsequently experience lower acute care utilization and expenditures than do those cared for by physicians with narrower ROS. Practice leaders and professional associations should consider how best to ensure that primary care physicians efficiently and effectively provide the office-based professional services most needed by their patients.


Asunto(s)
Médicos de Atención Primaria , Anciano , Humanos , Estados Unidos , Estudios Retrospectivos , Especies Reactivas de Oxígeno , Medicare , Costos de la Atención en Salud , Gastos en Salud , Atención Ambulatoria
16.
Circ Res ; 128(4): e46-e62, 2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33375813

RESUMEN

RATIONALE: Pericytes are capillary mural cells playing a role in stabilizing newly formed blood vessels during development and tissue repair. Loss of pericytes has been described in several brain disorders, and genetically induced pericyte deficiency in the brain leads to increased macromolecular leakage across the blood-brain barrier (BBB). However, the molecular details of the endothelial response to pericyte deficiency remain elusive. OBJECTIVE: To map the transcriptional changes in brain endothelial cells resulting from lack of pericyte contact at single-cell level and to correlate them with regional heterogeneities in BBB function and vascular phenotype. METHODS AND RESULTS: We reveal transcriptional, morphological, and functional consequences of pericyte absence for brain endothelial cells using a combination of methodologies, including single-cell RNA sequencing, tracer analyses, and immunofluorescent detection of protein expression in pericyte-deficient adult Pdgfbret/ret mice. We find that endothelial cells without pericyte contact retain a general BBB-specific gene expression profile, however, they acquire a venous-shifted molecular pattern and become transformed regarding the expression of numerous growth factors and regulatory proteins. Adult Pdgfbret/ret brains display ongoing angiogenic sprouting without concomitant cell proliferation providing unique insights into the endothelial tip cell transcriptome. We also reveal heterogeneous modes of pericyte-deficient BBB impairment, where hotspot leakage sites display arteriolar-shifted identity and pinpoint putative BBB regulators. By testing the causal involvement of some of these using reverse genetics, we uncover a reinforcing role for angiopoietin 2 at the BBB. CONCLUSIONS: By elucidating the complexity of endothelial response to pericyte deficiency at cellular resolution, our study provides insight into the importance of brain pericytes for endothelial arterio-venous zonation, angiogenic quiescence, and a limited set of BBB functions. The BBB-reinforcing role of ANGPT2 (angiopoietin 2) is paradoxical given its wider role as TIE2 (TEK receptor tyrosine kinase) receptor antagonist and may suggest a unique and context-dependent function of ANGPT2 in the brain.


Asunto(s)
Barrera Hematoencefálica/metabolismo , Pericitos/citología , Animales , Barrera Hematoencefálica/citología , Barrera Hematoencefálica/patología , Proliferación Celular , Células Cultivadas , Células Endoteliales/metabolismo , Células Endoteliales/fisiología , Linfocinas/deficiencia , Linfocinas/genética , Ratones , Ratones Endogámicos C57BL , Neovascularización Fisiológica , Pericitos/metabolismo , Pericitos/patología , Factor de Crecimiento Derivado de Plaquetas/deficiencia , Factor de Crecimiento Derivado de Plaquetas/genética , Análisis de la Célula Individual , Transcriptoma
17.
Rapid Commun Mass Spectrom ; 37(22): e9616, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37817342

RESUMEN

RATIONALE: The comprehensive analysis of formalin-fixed paraffin-embedded (FFPE) tissues is essential for retrospective clinical studies. However, detecting low-abundance proteins and obtaining proteome-scale data from FFPE samples pose analytical challenges in mass spectrometry-based proteomics. To overcome this challenge, our study focuses on implementing an isobaric labeling approach to improve the detection of low-abundance target proteins in FFPE tissues, thereby enhancing the qualitative and quantitative analysis. METHODS: We employed an isobaric labeling approach utilizing synthetic peptides or proteins to enable the qualitative and quantitative measurement of target proteins in FFPE tissue samples. To achieve this, we incorporated tandem mass tag (TMT)-labeled recombinant proteins or synthetic peptides into TMT-labeled metastatic breast cancer FFPE tissues. Through this strategy, we successfully detect coexisting CD276 (B7-H3) and CD147 proteins while identifying over 6000 proteins using targeted analysis of individual FFPE tissue sections. RESULTS: Our findings provide compelling evidence that the incorporation of isobaric labeling, along with the inclusion of TMT-labeled peptides or proteins, greatly enhances the detection of target proteins in FFPE tissue samples. By employing this approach, we were able to obtain robust qualitative measurements of CD276 and CD147 proteins, showcasing its effectiveness in identifying more than 6000 proteins in FFPE samples. CONCLUSIONS: The integration of an isobaric labeling approach, in conjunction with synthetic peptides or proteins, presents a valuable strategy for enhancing the detection and validation of target proteins in FFPE tissue analysis. This technique holds immense potential in retrospective clinical studies, as it enables comprehensive analysis of low-abundance proteins and facilitating proteome-scale investigations in FFPE samples. By leveraging this methodology, researchers can unlock new insights into disease mechanisms and advance our understanding of complex biological processes.


Asunto(s)
Proteoma , Proteómica , Proteoma/análisis , Proteómica/métodos , Adhesión en Parafina/métodos , Estudios Retrospectivos , Espectrometría de Masas en Tándem , Péptidos , Formaldehído
18.
Ann Fam Med ; 21(4): 313-321, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37487736

RESUMEN

PURPOSE: Despite evidence suggesting that high-quality primary care can prevent unnecessary hospitalizations, many primary care practices face challenges in achieving this goal, and there is little guidance identifying effective strategies for reducing hospitalization rates. We aimed to understand how practices in the Comprehensive Primary Care Plus (CPC+) program substantially reduced their acute hospitalization rate (AHR) over 2 years. METHODS: We used Bayesian analyses to identify the CPC+ practice sites having the highest probability of achieving a substantial reduction in the adjusted Medicare AHR between 2016 and 2018 (referred to here as AHR high performers). We then conducted telephone interviews with 64 respondents at 14 AHR high-performer sites and undertook within- and cross-case comparative analysis. RESULTS: The 14 AHR high performers experienced a 6% average decrease (range, 4% to 11%) in their Medicare AHR over the 2-year period. They credited various care delivery activities aligned with 3 strategies for reducing AHR: (1) improving and promoting prompt access to primary care, (2) identifying patients at high risk for hospitalization and addressing their needs with enhanced care management, and (3) expanding the breadth and depth of services offered at the practice site. They also identified facilitators of these strategies: enhanced payments through CPC+, prior primary care practice transformation experience, use of data to identify high-value activities for patient subgroups, teamwork, and organizational support for innovation. CONCLUSIONS: The AHR high performers observed that strengthening the local primary care infrastructure through practice-driven, targeted changes in access, care management, and comprehensiveness of care can meaningfully reduce acute hospitalizations. Other primary care practices taking on the challenging work of reducing hospitalizations can learn from CPC+ practices and may consider similar strategies, selecting activities that fit their context, personnel, patient population, and available resources.


Asunto(s)
Medicare , Atención Primaria de Salud , Humanos , Anciano , Estados Unidos , Teorema de Bayes , Atención a la Salud , Hospitalización
19.
Proc Natl Acad Sci U S A ; 117(25): 14259-14269, 2020 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-32513743

RESUMEN

The Hippo pathway controls organ size and tissue homeostasis by regulating cell proliferation and apoptosis. The LATS-mediated negative feedback loop prevents excessive activation of the effectors YAP/TAZ, maintaining homeostasis of the Hippo pathway. YAP and TAZ are hyperactivated in various cancer cells which lead to tumor growth. Aberrantly increased O-GlcNAcylation has recently emerged as a cause of hyperactivation of YAP in cancer cells. However, the mechanism, which induces hyperactivation of TAZ and blocks LATS-mediated negative feedback, remains to be elucidated in cancer cells. This study found that in breast cancer cells, abnormally increased O-GlcNAcylation hyperactivates YAP/TAZ and inhibits LATS2, a direct negative regulator of YAP/TAZ. LATS2 is one of the newly identified O-GlcNAcylated components in the MST-LATS kinase cascade. Here, we found that O-GlcNAcylation at LATS2 Thr436 interrupted its interaction with the MOB1 adaptor protein, which connects MST to LATS2, leading to activation of YAP/TAZ by suppressing LATS2 kinase activity. LATS2 is a core component in the LATS-mediated negative feedback loop. Thus, this study suggests that LATS2 O-GlcNAcylation is deeply involved in tumor growth by playing a critical role in dysregulation of the Hippo pathway in cancer cells.


Asunto(s)
Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Apoptosis , Proliferación Celular , Células HEK293 , Vía de Señalización Hippo , Homeostasis , Humanos , Fosforilación
20.
Health Promot Pract ; 24(1_suppl): 46S-55S, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36999505

RESUMEN

People living in rural areas of the United States, especially in the southern region, are much less likely to walk or cycle for leisure time or transportation. The purpose of this study is to provide a more detailed community-level estimate of walking and cycling behaviors and attitudes among adults living in a rural county (Hardeman County, TN) participating in a High Obesity Program (HOP) from the Centers for Disease Control and Prevention. Telephone interviews and online surveys regarding walking and cycling behaviors, attitudes, and perceptions of the built environment were completed by 634 adults. Questions originated from the 2002 National Survey of Bicyclist and Pedestrian Attitudes and Behavior. Respondents were classified as walkers, cyclists, or both. Chi-square and logistic regression were used for data analysis. Of adults in this county, 67.2% were walkers and 16.2% cyclists. Both forms of active living tended to decrease with age, especially after 50 years. Walking was associated with younger ages, 2-person households, positive perceived health, and a feeling that walking was good for them. Cycling was only associated with age. Most people felt that their communities were safe places to walk or bike. Walking was most often done on roads or road shoulder. Social support and intrinsic motivators may also play a role in walking and bicycling in rural areas. Interventions that promote walking and cycling in rural areas should provide a means for social support, creating activity-friendly routes perceived to be safe, and enhanced destinations for places to be physically active.


Asunto(s)
Ciclismo , Características de la Residencia , Adulto , Humanos , Preescolar , Persona de Mediana Edad , Ejercicio Físico , Caminata , Transportes , Sudeste de Estados Unidos , Planificación Ambiental
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