RESUMEN
BACKGROUND: Lack of racial concordance between physicians and patients has been linked to health disparities and inequities. Studies show that patients prefer physicians who look like them; however, there are too few underrepresented minority physicians in the workforce. Hospitalists are Internal Medicine physicians who specialize in inpatient medicine. At our hospital, hospitalists care for 60% of hospitalized medical patients. We utilized the validated Tool to Assess Inpatient Satisfaction with Care from Hospitalists (TAISCH) to assess the effect of patient-provider race and gender concordance on patients' assessment of their physician's performance. METHODS: Four hundred thirty-seven inpatients admitted to the non-teaching hospitalist service, cared for by a unique hospitalist physician for two or more consecutive days, were surveyed using the validated TAISCH instrument. The influence of gender and racial concordance on TAISCH scores for patient - hospitalist pairs were assessed by comparing the specific dyads with the overall mean scores. T-tests were used to compare the means. Generalized estimating equations were used to account for clustering. RESULTS: Of the 34 hospitalist physicians in the analysis, 20% were African American (AA-non-Hispanic), 15% were Caucasians (non-Hispanic) and 65% were in the "other" category. The "other" category consisted of predominantly physicians of South East Asian decent (i.e. Indian subcontinent) and Hispanic. Of the 437 patients, 66% were Caucasians, and 32% were AA. The overall mean TAISCH score, as these 437 patients assessed their hospitalist provider was 3.8 (se = 0.60). The highest mean TAISCH score was for the Caucasian provider-AA patient dyads at 4.2 (se = 0.21, p = 0.05 compared to overall mean). The lowest mean TAISCH score was 3.5 (se = 0.14) seen in the AA provider/AA patient dyads, significantly lower than the overall mean (p = 0.013). There were no statistically significant differences noted between mean TAISCH scores of gender and racially concordant versus discordant doctor-patient dyads (all p's > 0.05). CONCLUSIONS: In the inpatient setting, it appears as if neither race nor gender concordance with the provider affects a patient's assessment of a hospitalist's performance.
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Médicos Hospitalarios , Satisfacción del Paciente , Relaciones Médico-Paciente , Grupos Raciales , Centros Médicos Académicos , Negro o Afroamericano , Estudios Transversales , Femenino , Hospitalización , Humanos , Masculino , Proyectos Piloto , Factores Sexuales , Encuestas y Cuestionarios , Estados Unidos , Población BlancaRESUMEN
BACKGROUND: Cigarette smoking is responsible for 5 million deaths worldwide each year, and is a major risk factor for cardiovascular and lung diseases. Cigarette smoke contains a complex mixture of over 4000 chemicals containing 10(15) free radicals. Studies show smoke is perceived by cells as an inflammatory and xenobiotic stimulus, which activates an immune response. The specific cellular mechanisms driving cigarette smoke-induced inflammation and disease are not fully understood, although the innate immune system is involved in the pathology of smoking related diseases. METHODOLOGY/PRINCIPLE FINDINGS: To address the impact of smoke as an inflammagen on the innate immune system, THP-1 cells and Human PBMCs were stimulated with 3 and 10% (v/v) cigarette smoke extract (CSE) for 8 and 24 hours. Total RNA was extracted and the transcriptome analysed using Illumina BeadChip arrays. In THP-1 cells, 10% CSE resulted in 80 genes being upregulated and 37 downregulated by ≥1.5 fold after 8 hours. In PBMCs stimulated with 10% CSE for 8 hours, 199 genes were upregulated and 206 genes downregulated by ≥1.5 fold. After 24 hours, the number of genes activated and repressed by ≥1.5 fold had risen to 311 and 306 respectively. The major pathways that were altered are associated with cell survival, such as inducible antioxidants, protein chaperone and folding proteins, and the ubiquitin/proteosome pathway. CONCLUSIONS: Our results suggest that cigarette smoke causes inflammation and has detrimental effects on the metabolism and function of innate immune cells. In addition, THP-1 cells provide a genetically stable alternative to primary cells for the study of the effects of cigarette smoke on human monocytes.
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Perfilación de la Expresión Génica/métodos , Inflamación/genética , Monocitos/metabolismo , Monocitos/patología , Fumar/genética , Línea Celular , Bases de Datos como Asunto , Regulación de la Expresión Génica , Redes Reguladoras de Genes/genética , Hemo-Oxigenasa 1/genética , Hemo-Oxigenasa 1/metabolismo , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Análisis de Componente Principal , Transducción de Señal/genética , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVE: To evaluate the therapeutic potential of the human epidermal growth factor receptor (HER) family inhibitor, herstatin, in an animal model of arthritis. METHODS: Constructs of herstatin and modified tissue plasminogen activator (tPA)-herstatin were expressed in HEK 293T cells, and secreted protein was analyzed by Western blotting. Tissue PA-herstatin adenovirus (Ad-tPA-Her) was prepared, and titers established. Gene expression of Ad-tPA-Her was determined by polymerase chain reaction using HeLa cells. Pharmacokinetics of gene and protein expression in vivo in liver tissue and serum samples were confirmed via intravenous administration of Ad-tPA-Her. Clinical signs of disease were monitored in arthritic DBA/1 mice after therapeutic administration of Ad-tPA-Her, and histologic analysis of hind foot specimens was performed. RESULTS: Native herstatin was not secreted in supernatants, while modified tPA-herstatin was detected in abundance. HeLa cells stably expressed the tPA-herstatin gene when infected with virus. Additionally, tPA-herstatin gene and protein expression was observed over time in mice treated with virus. Importantly, Ad-tPA-Her, when administered therapeutically to arthritic mice, controlled clinical and histologic signs of disease and reduced the number of joints with severe damage. CONCLUSION: Our results support the notion that the human epidermal growth factor receptor family has a role in the progression of collagen-induced arthritis. The novel tPA-herstatin fusion protein could be used as an effective therapeutic tool for control of inflammatory disorders involving an angiogenic component.
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Artritis Reumatoide/tratamiento farmacológico , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/uso terapéutico , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/patología , Artritis Reumatoide/patología , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacocinética , Masculino , Ratones , Proteínas Recombinantes de Fusión/farmacocinética , Índice de Severidad de la Enfermedad , Activador de Tejido Plasminógeno/uso terapéuticoRESUMEN
INTRODUCTION: Despite the advent of biological therapies for the treatment of rheumatoid arthritis, there is a compelling need to develop alternative therapeutic targets for nonresponders to existing treatments. Soluble receptors occur naturally in vivo, such as the splice variant of the cell surface receptor for vascular endothelial growth factor (VEGF)--a key regulator of angiogenesis in rheumatoid arthritis. Bioinformatics analyses predict that the majority of human genes undergo alternative splicing, generating proteins--many of which may have regulatory functions. The objective of the present study was to identify alternative splice variants (ASV) from cell surface receptor genes, and to determine whether the novel proteins encoded exert therapeutic activity in an in vivo model of arthritis. METHODS: To identify novel splice variants, we performed RT-PCR using an mRNA pool representing major human tissue types and tumors. Novel ASV were identified by alignment of each cloned sequence to its respective genomic sequence in comparison with full-length transcripts. To test whether these ASV have biologic activity, we characterized a subset of them for ligand binding, and for efficacy in an animal model of arthritis. The in vivo study was accomplished using adenoviruses expressing secreted ASV. RESULTS: We cloned 60 novel human ASV from 21 genes, encoding cell surface receptors--many of which are known to be important in the regulation of angiogenesis. The ASV were characterized by exon extension, intron retention and alternative exon utilization. Efficient expression and secretion of selected ASV--corresponding to VEGF receptor type 1, VEGF receptor type 2, VEGF receptor type 3, angiopoietin receptor Tie1, Met (receptor for hepatocyte growth factor), colony-stimulating factor 1 receptor, platelet-derived growth factor receptor beta, fibroblast growth factor receptor 1, Kit, and RAGE--was demonstrated, together with binding to their cognate ligands. Importantly, ASV derived from VEGF receptor type 1 and Tie1, and to a lesser extent from VEGF receptor type 2 and fibroblast growth factor receptor 1, reduced clinical signs of arthritis in vivo. The reduction was paralleled by decreased joint inflammation and destruction. CONCLUSION: The present study shows that unique ASV derived from receptors that play key roles in angiogenesis--namely, VEGF receptor type 1 and, for the first time, Tie1--can markedly reduce arthritis severity. More broadly, our results demonstrate that ASV are a source of novel proteins with therapeutic potential in diseases in which angiogenesis and cellular hyperplasia play a central role, such as rheumatoid arthritis.
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Artritis Reumatoide/tratamiento farmacológico , Proteínas Tirosina Quinasas Receptoras/uso terapéutico , Receptor TIE-1/uso terapéutico , Receptor 1 de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Angiopoyetina 1/metabolismo , Animales , Artritis Reumatoide/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Humanos , Ratones , Ratones Endogámicos DBA , Neovascularización Fisiológica/fisiología , Unión Proteica/fisiología , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/uso terapéutico , ARN Mensajero/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor TIE-1/metabolismo , Índice de Severidad de la Enfermedad , Venas Umbilicales/citología , Venas Umbilicales/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismoRESUMEN
The sloughing of root cap cells from the root tip is important because it assists the growing root in penetrating the soil. Using a promoter-reporter (GUS) and RT-PCR analysis, we identified an endo-beta-1,4-glucanase (AtCel5) of Arabidopsis thaliana that is expressed exclusively in root cap cells of both primary and secondary roots. Expression is inhibited by high concentrations of IAA, both exogenous and internal, as well as by ABA. AtCel5 expression begins once the mature tissue pattern is established and continues for 3 weeks. GUS staining is observed in both root cap cells that are still attached and cells that have already been shed. Using AtCel5-GUS as a marker, we observed that the root cap cells begin to separate at the sides of the tip while the cells of the central region of the tip separate last. Separation involves sequential tiers of intact cells that separate from the periphery of the root tip. A homozygous T-DNA insertion mutant that does not express AtCel5 forms the root cap and sheds root cap cells but sloughing is less efficient compared to wild type. The reduction in sloughing in the mutant does not affect the overall growth performance of the plant in loose media. The modest effect of abolishing AtCel5 expression suggests that there are multiple redundant genes regulating the process of sloughing of the root cap, including AtCel3/At1g71380, the paralog of the AtCel5 gene that is also expressed in the root cap cells. Thus, these two endo-1,4-beta-D-glucanases may have a role in the sloughing of border cells from the root tip. We propose that AtCel5, provides a new molecular marker to further analyze the process of root cap cell separation and a root cap specific promoter for targeting to the environment genes with beneficial properties for plant growth.