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1.
Cell ; 153(4): 828-39, 2013 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-23663781

RESUMEN

The most common form of heart failure occurs with normal systolic function and often involves cardiac hypertrophy in the elderly. To clarify the biological mechanisms that drive cardiac hypertrophy in aging, we tested the influence of circulating factors using heterochronic parabiosis, a surgical technique in which joining of animals of different ages leads to a shared circulation. After 4 weeks of exposure to the circulation of young mice, cardiac hypertrophy in old mice dramatically regressed, accompanied by reduced cardiomyocyte size and molecular remodeling. Reversal of age-related hypertrophy was not attributable to hemodynamic or behavioral effects of parabiosis, implicating a blood-borne factor. Using modified aptamer-based proteomics, we identified the TGF-ß superfamily member GDF11 as a circulating factor in young mice that declines with age. Treatment of old mice to restore GDF11 to youthful levels recapitulated the effects of parabiosis and reversed age-related hypertrophy, revealing a therapeutic opportunity for cardiac aging.


Asunto(s)
Envejecimiento , Proteínas Morfogenéticas Óseas/metabolismo , Cardiomegalia/metabolismo , Factores de Diferenciación de Crecimiento/metabolismo , Miocitos Cardíacos/metabolismo , Parabiosis , Animales , Presión Sanguínea , Femenino , Factores de Transcripción Forkhead/metabolismo , Humanos , Hipertrofia Ventricular Izquierda/metabolismo , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Miocitos Cardíacos/citología
2.
Genome Res ; 34(3): 484-497, 2024 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-38580401

RESUMEN

Transcriptional regulation controls cellular functions through interactions between transcription factors (TFs) and their chromosomal targets. However, understanding the fate conversion potential of multiple TFs in an inducible manner remains limited. Here, we introduce iTF-seq as a method for identifying individual TFs that can alter cell fate toward specific lineages at a single-cell level. iTF-seq enables time course monitoring of transcriptome changes, and with biotinylated individual TFs, it provides a multi-omics approach to understanding the mechanisms behind TF-mediated cell fate changes. Our iTF-seq study in mouse embryonic stem cells identified multiple TFs that trigger rapid transcriptome changes indicative of differentiation within a day of induction. Moreover, cells expressing these potent TFs often show a slower cell cycle and increased cell death. Further analysis using bioChIP-seq revealed that GCM1 and OTX2 act as pioneer factors and activators by increasing gene accessibility and activating the expression of lineage specification genes during cell fate conversion. iTF-seq has utility in both mapping cell fate conversion and understanding cell fate conversion mechanisms.


Asunto(s)
Diferenciación Celular , Factores de Transcripción , Animales , Ratones , Diferenciación Celular/genética , Linaje de la Célula/genética , Perfilación de la Expresión Génica/métodos , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/citología , Multiómica , ARN Citoplasmático Pequeño/genética , ARN Citoplasmático Pequeño/metabolismo , RNA-Seq/métodos , Análisis de Secuencia de ARN/métodos , Análisis de Expresión Génica de una Sola Célula , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Transcriptoma
3.
Nucleic Acids Res ; 51(8): 3806-3819, 2023 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-36951126

RESUMEN

The placenta is an essential organ that supports the growth and development of the fetus during pregnancy. However, cell type-specific enhancers and transcription factors (TFs), and the mechanisms underlying the maintenance and differentiation of trophoblast stem cell (TSC) populations in the human placenta remain elusive. Here, using human TSCs as a model system, we identify 31,362 enhancers that are enriched with the motifs of previously reported TSC-pivotal TFs, including TEAD4, GATA2/3 and TFAP2C. Subsequently, we identify 580 super-enhancers (SEs) and 549 SE-associated genes. These genes are robustly expressed in the human placenta and include numerous TFs, implying that SE-associated TFs (SE-TFs) may play crucial roles in placental development. Additionally, we identify the global binding sites of five TSC-pivotal SE-TFs (FOS, GATA2, MAFK, TEAD4 and TFAP2C), revealing that they preferentially co-occupy enhancers, regulate each other and form a trophoblast-active gene regulatory network. Loss-of-function studies unveil that the five TFs promote self-renewal of TSCs by activating proliferation-associated genes while repressing developmental genes. We further reveal that the five TFs exert conserved and unique functions on placental development between humans and mice. Our study provides important insights into the roles of human TSC-pivotal TFs in regulating placenta-specific gene expression programs.


Asunto(s)
Factores de Transcripción , Trofoblastos , Humanos , Femenino , Embarazo , Ratones , Animales , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Placenta/metabolismo , Células Madre/metabolismo , Diferenciación Celular/genética , Expresión Génica , Factores de Transcripción de Dominio TEA
4.
Proc Natl Acad Sci U S A ; 119(20): e2115709119, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35537047

RESUMEN

The placenta is a transient but important multifunctional organ crucial for healthy pregnancy for both mother and fetus. Nevertheless, limited access to human placenta samples and the paucity of a proper in vitro model system have hampered our understanding of the mechanisms underlying early human placental development and placenta-associated pregnancy complications. To overcome these constraints, we established a simple procedure with a short-term treatment of bone morphogenetic protein 4 (BMP4) in trophoblast stem cell culture medium (TSCM) to convert human primed pluripotent stem cells (PSCs) to trophoblast stem-like cells (TSLCs). These TSLCs show not only morphology and global gene expression profiles comparable to bona fide human trophoblast stem cells (TSCs) but also long-term self-renewal capacity with bipotency that allows the cells to differentiate into functional extravillous trophoblasts (EVT) and syncytiotrophoblasts (ST). These indicate that TSLCs are equivalent to genuine human TSCs. Our data suggest a straightforward approach to make human TSCs directly from preexisting primed PSCs and provide a valuable opportunity to study human placenta development and pathology from patients with placenta-related diseases.


Asunto(s)
Placentación , Células Madre Pluripotentes , Trofoblastos , Biomarcadores , Proteína Morfogenética Ósea 4 , Diferenciación Celular , Femenino , Humanos , Modelos Biológicos , Placenta , Embarazo , Trofoblastos/metabolismo
5.
Immunity ; 42(5): 942-52, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25979422

RESUMEN

CLEC16A variation has been associated with multiple immune-mediated diseases, including type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, celiac disease, Crohn's disease, Addison's disease, primary biliary cirrhosis, rheumatoid arthritis, juvenile idiopathic arthritis, and alopecia areata. Despite strong genetic evidence implicating CLEC16A in autoimmunity, this gene's broad association with disease remains unexplained. We generated Clec16a knock-down (KD) mice in the nonobese diabetic (NOD) model for type 1 diabetes and found that Clec16a silencing protected against autoimmunity. Disease protection was attributable to T cell hyporeactivity, which was secondary to changes in thymic epithelial cell (TEC) stimuli that drive thymocyte selection. Our data indicate that T cell selection and reactivity were impacted by Clec16a variation in thymic epithelium owing to Clec16a's role in TEC autophagy. These findings provide a functional link between human CLEC16A variation and the immune dysregulation that underlies the risk of autoimmunity.


Asunto(s)
Autoinmunidad/inmunología , Células Epiteliales , Lectinas Tipo C/metabolismo , Proteínas de Transporte de Monosacáridos/metabolismo , Linfocitos T/inmunología , Timo , Animales , Autoinmunidad/genética , Autofagia/inmunología , Línea Celular , Células Cultivadas , Diabetes Mellitus Tipo 1/inmunología , Modelos Animales de Enfermedad , Células Epiteliales/citología , Células Epiteliales/inmunología , Técnicas de Silenciamiento del Gen , Inmunohistoquímica , Lectinas Tipo C/genética , Ratones , Ratones Endogámicos NOD , Proteínas de Transporte de Monosacáridos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T/citología , Timocitos/citología , Timocitos/inmunología , Timo/citología , Timo/inmunología
6.
Cell Commun Signal ; 21(1): 215, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596656

RESUMEN

BACKGROUND: Toll-like receptor 7 (TLR7) is an endosomal TLR activated by single-stranded RNA, including endogenous microRNAs. Although TLR7 is known to promote inflammatory responses in pathophysiological conditions, its role in renal fibrosis has not been investigated. Here, we aim to investigate the inflammatory roles of TLR7 in kidney inflammation and fibrosis. METHODS: TLR7 knockout mice (Tlr7 -/-) subjected to AD-induced kidney injury were utilized to examine the role of TLR7 in kidney fibrosis. To elucidate the role of TLR7 in renal epithelial cells, NRK52E rat renal tubule epithelial cells were employed. RESULTS: Under fibrotic conditions induced by an adenine diet (AD), TLR7 was significantly increased in damaged tubule epithelial cells, where macrophages were highly infiltrated. TLR7 deficiency protected against AD-induced tubular damage, inflammation, and renal fibrosis. Under in vitro conditions, TLR7 activation increased NF-κB activity and induced chemokine expression, whereas TLR7 inhibition effectively blocked NF-κB activation. Furthermore, among the known TLR7 endogenous ligands, miR-21 was significantly upregulated in the tubular epithelial regions. In NRK52E cells, miR-21 treatment induced pro-inflammatory responses, which could be blocked by a TLR7 inhibitor. When the TLR7 inhibitor, M5049, was administered to the AD-induced renal fibrosis model, TLR7 inhibition significantly attenuated AD-induced renal inflammation and fibrosis. CONCLUSIONS: Overall, activation of TLR7 by endogenous miR-21 in renal epithelial cells contributes to inflammatory responses in a renal fibrosis model, suggesting a possible therapeutic target for the treatment of renal fibrosis. Video Abstract.


Asunto(s)
Enfermedades Renales , MicroARNs , Receptor Toll-Like 7 , Animales , Ratones , Ratas , Adenina , Células Epiteliales , Inflamación , MicroARNs/genética , FN-kappa B , Transducción de Señal , Enfermedades Renales/genética , Enfermedades Renales/patología , Fibrosis
7.
Opt Express ; 30(25): 44533-44544, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36522876

RESUMEN

Two NIR band-pass filters for CMOS image sensors are developed by incorporating NIR absorption dye and silver nanodisks simultaneously in a transparent polymer, one of which blocks the NIR near the wavelength of 750 nm and the other near 950 nm. They offer low NIR transmittance while maintaining high visible light transparency even at a thin film thickness of 500 nm. By superimposing the proposed NIR band-pass filters, an NIR cutoff filter with a thickness of 1 µm is formed that shields the NIR at wavelengths longer than 680 nm while remaining transparent in the visible range.

8.
Nat Immunol ; 10(9): 943-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19692995

RESUMEN

The progression of tuberculosis from a latent, subclinical infection to active disease that culminates in the transmission of infectious bacilli is determined locally at the level of the granuloma. This progression takes place even in the face of a robust immune response that, although it contains infection, is unable to eliminate the bacterium. The factors or environmental conditions that influence this progression remain to be determined. Recent advances have indicated that pathogen-induced dysregulation of host lipid synthesis and sequestration serves a critical role in this transition. The foamy macrophage seems to be a key participant in both sustaining persistent bacteria and contributing to the tissue pathology that leads to cavitation and the release of infectious bacilli.


Asunto(s)
Células Espumosas/fisiología , Granuloma/etiología , Tuberculosis/inmunología , Animales , Progresión de la Enfermedad , Granuloma/inmunología , Granuloma/patología , Humanos , Isocitratoliasa/fisiología , Lípidos/biosíntesis , Lipoproteínas LDL/metabolismo , Fagosomas/fisiología , Tuberculosis/patología , Factor de Necrosis Tumoral alfa/fisiología
9.
BMC Cardiovasc Disord ; 20(1): 360, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32762650

RESUMEN

BACKGROUND: Neprilysin has an essential role in regulating fluid balance and vascular resistance, and neprilysin inhibitors have shown beneficial effects in patients with heart failure. However, the potential predictive value of neprilysin levels as a biomarker for cardiovascular risk remains unclear. The aim of this study was to assess the prognostic value of soluble neprilysin (sNEP) levels in patients with ischemic heart disease. METHODS: Neprilysin levels were measured in 694 consecutive patients with coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI). These patients were classified into two groups according to their serum levels of neprilysin and categorized into the lower neprilysin group (n = 348) and the higher neprilysin group (n = 346). The primary clinical endpoint was all-cause mortality, and the secondary endpoint was a composite of major adverse cardiac events (MACE). RESULTS: The median sNEP level was 76.0 pg/ml. The median sNEP levels were higher in patients with left ventricular ejection fraction (LVEF) ≥40% (77.6 pg/ml, interquartile range 46.6-141.3) than in those with LVEF < 40% (70.0 pg/ml, interquartile range 47.1-100.6; P = 0.032). Among all patients, each clinical outcome and MACE did not differ significantly according to the groups divided into median, tertile, or quartile of sNEP levels during a median follow-up of 28.4 months. We did not find a significant relationship between sNEP levels and clinical outcomes in multivariate Cox regression analysis. Among patients with LVEF < 40%, an increased sNEP level was associated with a higher rate of all-cause death (adjusted hazard ratio 2.630, 95% confidence interval 1.049-6.595, P = 0.039). CONCLUSION: Serum sNEP levels are not associated with long-term mortality or cardiovascular outcomes after PCI in patients with CAD. In the LVEF < 40% group, increased sNEP levels may be associated with a higher risk of all-cause death.


Asunto(s)
Enfermedad de la Arteria Coronaria/terapia , Neprilisina/sangre , Intervención Coronaria Percutánea , Anciano , Biomarcadores/sangre , Causas de Muerte , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Estudios Retrospectivos , Volumen Sistólico , Factores de Tiempo , Resultado del Tratamiento , Función Ventricular Izquierda
10.
Arch Toxicol ; 94(2): 523-539, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31797001

RESUMEN

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are used in various fields but raise concerns regarding human health and environmental consequences. Among PFASs, perfluorooctanoic acid (PFOA) and short-chain perfluoroalkyl carboxylic acids (SC PFCAs) are detectable in skin-contact consumer products and have dermal absorption potential. Here, we investigated the effects of dermal exposure to PFOA and SC PFCAs using in vitro and in vivo models. Human skin equivalents were topically treated with 0.25 mM and 2.5 mM PFOA and SC PFCAs (perfluoropentanoic acid, PFPeA; perfluorohexanoic acid, PFHxA; and perfluoroheptanoic acid, PFHpA) for 6 days, and cell viability, interleukin (IL)-1α, oxidative stress markers (malondialdehyde, MDA; and 8-hydroxydeoxyguanosine, 8-OHdG), and histopathology were examined. MDA levels were significantly higher in the PFASs groups than in controls. Compared with SC PFCAs, 2.5 mM PFOA caused more IL-1α (p < 0.001) release, decreased skin thickness and microscopic abnormalities. To evaluate systemic effects, Sprague Dawley (SD) rats were dermally treated with 250 and 1000 mg/kg PFHpA for 2 weeks and clinical and anatomic pathology were assessed. At 1000 mg/kg, 83% of the rats died, with severe ulcerative dermatitis at the application site. Adverse PFHpA-treated systemic changes were observed in the kidney, liver and testes, and histopathologic lesions such as renal tubular necrosis, hepatocellular necrosis, and germ cell degeneration were seen at 250 and 1000 mg/kg. Our study suggests that SC PFCAs have fewer effects on the skin than PFOA, but SC PFCAs can have adverse effects on major organs with systemic exposure at high concentrations.


Asunto(s)
Ácidos Carboxílicos/toxicidad , Fluorocarburos/toxicidad , Piel/citología , Piel/efectos de los fármacos , Pruebas de Toxicidad Subaguda/métodos , 8-Hidroxi-2'-Desoxicoguanosina/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Ácidos Carboxílicos/química , Técnicas de Cultivo de Célula , Relación Dosis-Respuesta a Droga , Femenino , Fluorocarburos/química , Ácidos Heptanoicos/toxicidad , Humanos , Interleucina-1alfa/metabolismo , Masculino , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Piel/metabolismo , Relación Estructura-Actividad
11.
J Korean Med Sci ; 35(32): e297, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32808513

RESUMEN

BACKGROUND: There is limited information describing the presenting characteristics and dynamic clinical changes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection diagnosed in the early phase of illness. This study is a case series of patients with coronavirus disease 2019 (COVID-19) admitted to 11 hospitals in Korea. METHODS: Patients with confirmed SARS-CoV-2 infection by positive polymerase chain reaction (PCR) testing of respiratory specimens by active surveillance that were finally discharged between February 20 and April 30, 2020 were included. Patients were classified into mild and non-mild groups on initial admission according to oxygen demand and Sequential Organ Failure Assessment score, and the mild group was followed up and subgrouped into non-aggravation and aggravation groups. RESULTS: A total of 161 patients with SARS-CoV2 infection were enrolled. Among the mild group of 136 patients, 11.7% of patients experienced clinical aggravation during hospitalization, but there was no initial clinical parameter on admission predicting their aggravation. Fever (odds ratio [OR], 4.56), thrombocytopenia (OR, 12.87), fever (OR, 27.22) and lactate dehydrogenase (LDH) > 300 U/L (OR, 18.35), and CRP > 1 mg/dL (OR, 11.31) significantly indicated aggravation in the 1st, 2nd, 3rd, and 4th 5-day periods, respectively. PCR positivity lasted for a median of 22 days and 32 days after the onset of illness in the non-aggravation and aggravation groups, respectively. CONCLUSION: Old age was associated with early severe presentation. Clinical aggravation among asymptomatic or mild patients could not be predicted initially but was heralded by fever and several laboratory markers during the clinical course.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Adulto , Anciano , COVID-19 , Infecciones por Coronavirus/tratamiento farmacológico , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxígeno/uso terapéutico , Pandemias , Neumonía Viral/tratamiento farmacológico , Reacción en Cadena en Tiempo Real de la Polimerasa , SARS-CoV-2 , Carga Viral
12.
Echocardiography ; 35(10): 1533-1541, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29920763

RESUMEN

PURPOSE: Recently, the diastolic strain rate (DSR) utilizing speckle-tracking echocardiography has been proposed as a novel parameter for left ventricular diastolic function. We aimed to present normal reference data for those in a large-sized, selected group of healthy individuals. METHODS: The current study was a part of the Normal echOcardiogRaphic Measurements in KoreAn popuLation (NORMAL), a prospective nationwide survey from 23 centers in Korea. We analyzed 447 subjects (age 48 ± 15 years, 234 females) without any history of cardiovascular disease and presented the early and late DSRs (SRe and SRa , respectively) in a total and gender-/age-specified groups. RESULTS: Among the total subjects, the mean SRe and SRa were 1.6 ± 0.4 S-1 and 0.8 ± 0.3 S-1 , respectively. With increasing age, there were significant trends of decreasing SRe and increasing SRa . Although both gender groups showed comparable age, the female group presented significantly higher SRe compared to male subjects with age of 20-59 years, which diminished after the age of 60 years. However, the SRa was comparable between genders in all age groups. On multiple linear regression, age showed independent associations with both SRe (ß = -0.132, P = .010) and SRa (ß = 0.440, P < .001), whereas gender did not show any association with SRe or SRa . CONCLUSION: We present normal reference data of a novel parameter, DSR, in a large-sized selected group with healthy Korean subjects. Additionally, we present significant age-related changes both in SRe and SRa without the impact of their gender.


Asunto(s)
Diástole/fisiología , Ecocardiografía/métodos , Corazón/fisiología , Adulto , Factores de Edad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Valores de Referencia , República de Corea , Factores Sexuales
13.
J Immunol ; 194(10): 4784-95, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25870244

RESUMEN

The thymus reaches its maximum size early in life and then begins to shrink, producing fewer T cells with increasing age. This thymic decline is thought to contribute to age-related T cell lymphopenias and hinder T cell recovery after bone marrow transplantation. Although several cellular and molecular processes have been implicated in age-related thymic involution, their relative contributions are not known. Using heterochronic parabiosis, we observe that young circulating factors are not sufficient to drive regeneration of the aged thymus. In contrast, we find that resupplying young, engraftable thymic epithelial cells (TECs) to a middle-aged or defective thymus leads to thymic growth and increased T cell production. Intrathymic transplantation and in vitro colony-forming assays reveal that the engraftment and proliferative capacities of TECs diminish early in life, whereas the receptivity of the thymus to TEC engraftment remains relatively constant with age. These results support a model in which thymic growth and subsequent involution are driven by cell-intrinsic changes in the proliferative capacity of TECs, and further show that young TECs can engraft and directly drive the growth of involuted thymuses.


Asunto(s)
Envejecimiento/fisiología , Células Epiteliales/trasplante , Timo/crecimiento & desarrollo , Animales , Proliferación Celular , Citometría de Flujo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Parabiosis
14.
Mar Drugs ; 15(6)2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28617322

RESUMEN

The protective effects of a chondroitin sulfate-rich extract (CSE) from skate cartilage against lipopolysaccharide (LPS)-induced hepatic damage were investigated, and its mechanism of action was compared with that of chondroitin sulfate (CS) from shark cartilage. ICR mice were orally administrated 200 mg/kg body weight (BW) of CS or 400 mg/kg BW of CSE for 3 consecutive days, followed by a one-time intraperitoneal injection of LPS (20 mg/kg BW). The experimental groups were vehicle treatment without LPS injection (NC group), vehicle treatment with LPS injection (LPS group), CS pretreatment with LPS injection (CS group), and CSE pretreatment with LPS injection (CSE group). Hepatic antioxidant enzyme expression levels in the CS and CSE groups were increased relative to those in the LPS group. In LPS-insulted hepatic tissue, inflammatory factors were augmented relative to those in the NC group, but were significantly suppressed by pretreatment with CS or CSE. Moreover, CS and CSE alleviated the LPS-induced apoptotic factors and mitogen-activated protein kinase (MAPK). In addition, CS and CSE effectively decreased the serum lipid concentrations and downregulated hepatic sterol regulatory element-binding proteins expression. In conclusion, the skate CSE could protect against LPS-induced hepatic dyslipidemia, oxidative stress, inflammation, and apoptosis, probably through the regulation of MAPK signaling.


Asunto(s)
Cartílago/química , Sulfatos de Condroitina/farmacología , Lipopolisacáridos/toxicidad , Hígado/efectos de los fármacos , Rajidae , Animales , Peso Corporal/efectos de los fármacos , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos ICR , Factor de Necrosis Tumoral alfa/análisis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
J Korean Med Sci ; 32(3): 407-414, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28145642

RESUMEN

Two prospective, multi-centre, observational studies (GlaxoSmithKline [GSK] identifier No. 110938 and 112519) were performed over 2 influenza seasons (2007-2008 and 2008-2009) in the Republic of Korea (ROK) with the aim to evaluate the burden of laboratory-confirmed influenza (LCI) in patients ≥ 50 years of age seeking medical attention for acute respiratory illness (ARI). The median participant age was 58 years in the 2007-2008 season and 60 years in the 2008-2009 season. LCI was observed in 101/346 (29.2%) of ARI patients in the 2007-2008 season and in 166/443 (37.5%) of ARI patients in the 2008-2009 season. Compared to patients with non-influenza ARI, those with LCI had higher rates of decreased daily activities (60.4% vs. 32.9% in 2007-2008 and 46.4% vs. 25.8% in 2008-2009), work absenteeism (51.1% vs. 25.6% and 14.4% vs. 7.7%), and longer duration of illness. These results indicated that influenza is an important cause of ARI in adults aged 50 and older causing more severe illness than non-influenza related ARI.


Asunto(s)
Gripe Humana/diagnóstico , Infecciones del Sistema Respiratorio/diagnóstico , Actividades Cotidianas , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Gripe Humana/epidemiología , Gripe Humana/patología , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Estudios Prospectivos , República de Corea/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/patología , Estaciones del Año , Índice de Severidad de la Enfermedad
16.
Diabetologia ; 58(4): 809-18, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25537833

RESUMEN

AIMS/HYPOTHESIS: Fibroblast growth factor 21 (FGF21) is an endocrine hormone that exhibits anti-diabetic and anti-obesity activity. FGF21 expression is increased in patients with and mouse models of obesity or nonalcoholic fatty liver disease (NAFLD). However, the functional role and molecular mechanism of FGF21 induction in obesity or NAFLD are not clear. As endoplasmic reticulum (ER) stress is triggered in obesity and NAFLD, we investigated whether ER stress affects FGF21 expression or whether FGF21 induction acts as a mechanism of the unfolded protein response (UPR) adaptation to ER stress induced by chemical stressors or obesity. METHODS: Hepatocytes or mouse embryonic fibroblasts deficient in UPR signalling pathways and liver-specific eIF2α mutant mice were employed to investigate the in vitro and in vivo effects of ER stress on FGF21 expression, respectively. The in vivo importance of FGF21 induction by ER stress and obesity was determined using inducible Fgf21-transgenic mice and Fgf21-null mice with or without leptin deficiency. RESULTS: We found that ER stressors induced FGF21 expression, which was dependent on a PKR-like ER kinase-eukaryotic translation factor 2α-activating transcription factor 4 pathway both in vitro and in vivo. Fgf21-null mice exhibited increased expression of ER stress marker genes and augmented hepatic lipid accumulation after tunicamycin treatment. However, these changes were attenuated in inducible Fgf21-transgenic mice. We also observed that Fgf21-null mice with leptin deficiency displayed increased hepatic ER stress response and liver injury, accompanied by deteriorated metabolic variables. CONCLUSIONS/INTERPRETATION: Our results suggest that FGF21 plays an important role in the adaptive response to ER stress- or obesity-induced hepatic metabolic stress.


Asunto(s)
Estrés del Retículo Endoplásmico , Retículo Endoplásmico/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Hepatocitos/metabolismo , Obesidad/metabolismo , Estrés Fisiológico , Factor de Transcripción Activador 4/metabolismo , Adaptación Fisiológica , Animales , Modelos Animales de Enfermedad , Factor 2 Eucariótico de Iniciación/metabolismo , Factores de Crecimiento de Fibroblastos/deficiencia , Factores de Crecimiento de Fibroblastos/genética , Células Hep G2 , Humanos , Ratones Noqueados , Ratones Obesos , Obesidad/genética , Obesidad/fisiopatología , Interferencia de ARN , Transducción de Señal , Factores de Tiempo , Transfección , Respuesta de Proteína Desplegada , eIF-2 Quinasa/metabolismo
17.
Echocardiography ; 32(3): 475-82, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24975842

RESUMEN

BACKGROUND: Microvascular obstruction becomes more severe with longer duration of ischemia, such as chronic total occlusion (CTO) which used to have collateral flow. In this study, we explored the correlation between parameters measured using quantitative myocardial perfusion contrast echocardiography (MCE) and the angiographic collateral flow grades in patients with CTO. Furthermore, we investigated the usefulness of the parameters of quantitative MCE for the measurement of microvasculature changes after revascularization of CTO lesions. METHODS: Between January 2011 and January 2013, 44 patients who had undergone coronary angiography (CAG) due to chest pain and had confirmed CTO lesions were enrolled in this prospective observational study. All patients had baseline MCE within 24 hours after diagnostic CAG. Patients were then assigned to one of two groups: a medical therapy group (Group I, n = 20) or a reperfusion group with percutaneous coronary intervention (PCI) (Group II, n = 24). All patients had follow-up MCE 3 months later. RESULTS: Consistent with the CAG results in both groups, on baseline MCE, the myocardial blood flow (AI × ß) values were higher in Grade III collateral flow than in Grade I or II collateral flow (AI of collateral flow Grade I vs. Grade II vs. Grade III: 2.34 ± 2.65 vs. 2.52 ± 2.67 vs. 3.87 ± 4.57, P = 0.038). The plateau acoustic intensity (AI) and wall-motion score index (WMSI) were significantly improved at the 3-month follow-up after successful reperfusion with PCI (5.75 ± 3.52 before vs. 8.11 ± 6.02 after, P = 0.004) and (1.76 ± 0.83 before vs. 1.43 ± 0.64 after, P ≤ 0.001), respectively. However, the AI and WMSI values were not improved in the medical treatment group, (6.04 ± 4.64 before vs. 6.01 ± 5.52 after, P = 0.966) and (1.61 ± 0.82 before vs. 1.66 ± 0.67 after, P = 0.616), respectively. CONCLUSIONS: MCE is a useful tool for estimating microvascularity in patients with CTO lesions and correlates well with angiographic collateral flow.


Asunto(s)
Estenosis Coronaria/diagnóstico por imagen , Ecocardiografía/métodos , Microvasos/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Neovascularización Patológica/diagnóstico por imagen , Anciano , Algoritmos , Enfermedad Crónica , Circulación Colateral , Medios de Contraste , Estenosis Coronaria/complicaciones , Estenosis Coronaria/fisiopatología , Femenino , Humanos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Neovascularización Patológica/fisiopatología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
J Appl Psychol ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39023995

RESUMEN

Owing to consecutive global crises (e.g., the COVID-19 pandemic, multiple regional wars), interest has grown in understanding and promoting organizational resilience. There is scant knowledge about how a human resource management (HRM) system can foster organizational resilience. This study examines the role of a high-performance work system in the organizational resilience process during the COVID-19 pandemic. We focus on two properties of the resilience process: stability during the jolt phase and flexibility during the turnaround phase. We test our hypotheses using quarterly sales data from 268 Korean firms during the COVID-19 pandemic. Our findings show that an high-performance work system reduces the severity of loss during the jolt phase (i.e., it maintains stability) through an increased climate of trust and enhances the scale of recovery during the turnaround phase (i.e., it improves flexibility) through an increased climate of innovation. We advance research on HRM, organizational resilience, and crisis management, showing how an HRM system can foster two essential properties for the resilience process to unfold effectively over time after the onset of a crisis. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

19.
PLoS One ; 19(3): e0299899, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38442122

RESUMEN

BACKGROUND: Developing contrast-associated acute kidney injury (CA-AKI) following percutaneous coronary intervention (PCI) is closely related to patient-related risk factors as well as contrast administration. The diagnostic and prognostic roles of neutrophil gelatinase-associated lipocalin (NGAL) in CA-AKI following PCI are not well established. METHODS: Consecutive patients undergoing PCI were enrolled prospectively. CA-AKI was defined as an increase in the serum creatinine level ≥0.3 mg/dL within 48 hours or ≥1.5 times the baseline within 7 days after PCI. Serum NGAL concentrations were determined immediately before and 6 hours after PCI. The participants were classified into four NGAL groups according to the pre- and post-PCI NGAL values at 75th percentile. RESULTS: CA-AKI occurred in 38 (6.4%) of 590 patients. With chronic kidney disease status (hazard ratio [HR] 1.63, 95% confidence interval [CI]: 1.06-2.52), NGAL groups defined by the combination of pre- and 6 h post-PCI values were independently associated with the occurrence of CA-AKI (HR 1.69, 95% CI: 1.16-2.45). All-cause mortality for 29-month follow-ups was different among NGAL groups (log-rank p<0.001). Pre-PCI NGAL levels significantly correlated with baseline cardiac, inflammatory, and renal markers. Although post-PCI NGAL levels increased in patients with larger contrast administration, contrast media made a relatively limited contribution to the development of CA-AKI. CONCLUSION: In patients undergoing PCI, the combination of pre- and post-PCI NGAL values may be a useful adjunct to current risk-stratification of CA-AKI and long-term mortality. CA-AKI is likely caused by systemic reserve deficiency rather than contrast administration itself.


Asunto(s)
Lesión Renal Aguda , Intervención Coronaria Percutánea , Insuficiencia Renal Crónica , Humanos , Lipocalina 2 , Intervención Coronaria Percutánea/efectos adversos , Lesión Renal Aguda/inducido químicamente , Riñón
20.
Eye (Lond) ; 38(2): 284-291, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37537389

RESUMEN

OBJECTIVE: The study attempted to identify clinical characteristics associated with structural progression in open-angle glaucoma (OAG) in the presence of MvD in different locations. METHODS: A total of 181 consecutive OAG eyes (follow-up 7.3 ± 4.0 years), which demonstrated peripapillary choroidal MvD (defined as a focal capillary loss with no visible microvascular network in choroidal layer) on optical coherence tomography (OCT) angiography (OCTA), were divided based on the location of MvD. Structural progression was determined using trend-based analysis of the Guided Progression Analysis software of Cirrus OCT. RESULTS: MvD was identified in the temporal quadrant in 110 eyes (temporal MvD; 60.5 ± 12.6 years), and in the inferior quadrant in 71 eyes (inferior MvD; 60.3 ± 11.1 years). After adjusting for age, average intraocular pressure (IOP) and baseline retinal nerve fibre layer (RNFL) thickness and visual field mean deviation, inferior MvD eyes showed faster rates of thinning in the inferior RNFL (mean (95% CI); -0.833 (-1.298 to -0.367)) compared to temporal MvD eyes (-0.144 (-0.496 to 0.207)) when long-term IOP fluctuation was larger than the median value (1.7 mmHg; P = 0.022). Long-term IOP fluctuations were independently associated with inferior RNFL thinning in eyes with inferior MvD (P = 0.002) but not in eyes with temporal MvD. CONCLUSIONS: In OAG eyes, the rates of RNFL and GCIPL thinning were comparable regardless of MvD locations. However, inferior MvD is associated with faster RNFL and GCIPL thinning in the same quadrant when long-term IOP fluctuation is present. Structural progression in the presence of temporal MvD was less associated with IOP fluctuation.


Asunto(s)
Glaucoma de Ángulo Abierto , Disco Óptico , Humanos , Glaucoma de Ángulo Abierto/diagnóstico , Células Ganglionares de la Retina , Disco Óptico/irrigación sanguínea , Presión Intraocular , Tomografía de Coherencia Óptica/métodos , Microvasos
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