RESUMEN
BACKGROUND: Assessment of resident performance is a complex task. PURPOSE: To correlate performance on a 4th-year objective structured clinical examination (OSCE) with residency program director assessment, class rank, and U.S. Medical Licensing Examination (USMLE) scores. METHODS: We surveyed program directors about the performance of 50 graduates from our medical school chosen to represent the highest (OSCEHI) and lowest (OSCELO) 25 performers on our required 4th-year OSCE. Program directors were unaware of the OSCE scores of the graduates. RESULTS: OSCE scores did not correlate with Likert scores for any survey parameter studied (r < .23, p > .13 for all comparisons). Similarly, program director evaluations did not correlate with class rank or USMLE scores (r < .26, p > .09 for all comparisons). CONCLUSIONS: We concluded that program director evaluations of resident performance do not appear to correlate with objective tests of either clinical skills or knowledge taken during medical school. These findings suggest that more structured and objective evaluative tools might improve postgraduate training program assessment of trainees.
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Competencia Clínica , Educación de Postgrado en Medicina/normas , Educación de Pregrado en Medicina/normas , Evaluación Educacional/métodos , Internado y Residencia , Estudios de Cohortes , Humanos , Simulación de Paciente , Estadísticas no Paramétricas , Estados UnidosRESUMEN
BACKGROUND: Recent shifts in reimbursement toward capitation makes appointment availability a significant resource and stimulates us to understand primary care physician (hereafter referred to as "provider") behavior concerning appointment assignment. The results of prior studies suggest significant provider variability in this area. OBJECTIVE: To examine the influences on assigning patient revisit intervals in the ambulatory setting. METHODS: Survey regarding general care issues of hypothetical diabetic and hypertensive patients seen in an ambulatory setting was given to 62 providers in the Internal Medicine Program at the Tulane University Internal Medicine Residency Program and outpatient clinics, New Orleans, La. Measurements evaluated included survey responses for demographics (sex, year of birth, year of graduation from medical school, and level of training) and practice style (decision to change therapy, order tests, and recommended return appointment interval in weeks) variables. RESULTS: The response rate was 89% (56 providers). Most respondents were men (n = 39). Wide variation was noted in assignment of reappointment interval with mean return intervals for the scenarios ranging from 2.2 to 20.5 weeks. Significant influences on provider practice included patient stability (P<.001), the decision to change therapy (P = .001), and the decision to order tests (P = .001). All correlated with an earlier return appointment. Some providers exhibited test-ordering tendencies across scenarios. Sex was a significant provider independent variable and was not influenced by other study variables. Female providers assigned earlier reappointment intervals for their patients. CONCLUSIONS: Wide variation exists among practitioners with similar training background and practice setting. As expected, patient stability was a major determinant of assigned return interval. Test-ordering behaviors may consume appointments inappropriately and may be a productive area for efforts to reduce provider variability. The influence of the provider's sex on scheduling follow-up appointments warrants further investigation.
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Atención Ambulatoria/estadística & datos numéricos , Citas y Horarios , Capitación/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Femenino , Humanos , Louisiana , Masculino , Factores Sexuales , Encuestas y Cuestionarios , Factores de TiempoAsunto(s)
Revelación , Enfermedades Pulmonares Intersticiales , Enfermedades Profesionales , Industria Textil , Contratos , Humanos , NylonsRESUMEN
BACKGROUND/AIMS: Portal hypertension is often accompanied by a hyperdynamic circulatory syndrome. Tumor necrosis factor (TNF) alpha causes vasodilatation and a hyperdynamic state in mammals by activating nitric oxide synthesis. The aim of this study was to investigate whether TNF-alpha plays a role in developing the hyperdynamic syndrome in portal hypertension. METHODS: Portal-hypertensive rats, induced by partial ligation of the portal vein (PVL), were used. In experiment 1, rats that underwent PVL were treated with polyclonal anti-mouse TNF-alpha or placebo intravenously the same day of the PVL operation and 24 hours before hemodynamic studies. Hemodynamic studies were performed 5 days after PVL. In experiment 2, rats that underwent PVL received anti-TNF-alpha or placebo intravenously 3 days and 24 hours before hemodynamics as in experiment 1. Hemodynamics were performed 14 days after the PVL operation. TNF-alpha blood levels were measured using a bioassay. RESULTS: Anti-TNF-alpha treatment induced a significant increase in mean arterial pressure, heart rate, and systemic vascular resistance and a significant decrease in cardiac index, portal pressure, and TNF-alpha levels in comparison with placebo animals. No significant effects were observed in sham rats. CONCLUSIONS: Anti-TNF-alpha treatment in rats that underwent PVL significantly blunts the development of the hyperdynamic circulation and reduces portal pressure. TNF-alpha may play a role in the hemodynamic abnormalities of portal hypertension.
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Circulación Sanguínea/fisiología , Hipertensión Portal/fisiopatología , Circulación Esplácnica/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Vasodilatación/fisiología , Animales , Anticuerpos/inmunología , Hemodinámica/fisiología , Masculino , Ratas , Síndrome , Factor de Necrosis Tumoral alfa/análisis , Factor de Necrosis Tumoral alfa/inmunologíaRESUMEN
The effects of treatment with a perfluorochemical emulsion plus carbogen on radiation pneumonitis were examined in a rat model system. Rats received thoracic irradiation (15 Gy) and radiation reactions in the lungs were assessed 25 and 35 days later using bronchoalveolar lavage and histologic assessments. The irradiated lungs showed the expected evidence of acute radiation pneumonitis, including protein leaks and also alveolar infiltrates and interstitial infiltrates. Administration of a perfluoro-chemical emulsion (Fluosol; 15 ml/kg) plus carbogen breathing for 30 min before and during irradiation did not enhance the reactions seen in the irradiated lungs.
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Dióxido de Carbono/administración & dosificación , Fluorocarburos/administración & dosificación , Oxígeno/administración & dosificación , Neumonitis por Radiación/etiología , Radioterapia/efectos adversos , Animales , Pulmón/efectos de los fármacos , Pulmón/efectos de la radiación , Masculino , Oxígeno/metabolismo , RatasRESUMEN
IL-11 and IL-6 are fibroblast-derived cytokines with overlapping biologic properties. To determine whether IL-11 and IL-6 are similarly regulated, we characterized the effects of rIL-1 and TGF-beta (beta 1 and beta 2) on human lung fibroblast IL-11 production and compared this regulation with that of IL-6. Unstimulated fibroblasts did not produce significant amounts of IL-11, whereas rIL-1 alpha and TGF-beta were dose-dependent stimulators of IL-11 protein production, mRNA accumulation, and gene transcription. rIL-1 alpha and TGF-beta also interacted in a synergistic fashion to further increase IL-11 protein production and mRNA accumulation. The effects of rIL-1 and TGF-beta individually were not altered by the cyclic nucleotide-dependent protein kinase inhibitor HA1004, protein kinase C (PKC) inhibition with staurosporine, or chronic phorbol ester preincubation, or the calmodulin antagonists W7 and TFP. The effects of rIL-1 alpha and TGF-beta in combination were also unaltered by HA1004, staurosporine, and chronic phorbol ester exposure. A23187, however, did induce IL-11 mRNA accumulation and W7 and TFP did reverse the synergistic stimulation caused by rIL-1 and TGF-beta in combination. In contrast with the regulation of IL-11, TGF-beta did not effectively stimulate IL-6 mRNA accumulation, rIL-1 alpha was a more potent stimulator of IL-6 than IL-11 production, and rIL-1-induced IL-6 mRNA accumulation was augmented by W7 and TFP. These studies demonstrate that: 1) rIL-1, TGF-beta, and agents that increase intracellular calcium stimulate lung fibroblast IL-11; 2) the IL-11 stimulatory effects of rIL-1 and TGF-beta are, at least partially, transcriptionally mediated and are the result of signal transduction pathways that are largely PKC, cyclic nucleotide, and calmodulin independent; and 3) rIL-1 and TGF-beta interact in a synergistic fashion to further increase fibroblast IL-11 production and that this synergy is mediated by a largely PKC- and cyclic nucleotide-independent and calmodulin-dependent activation pathway. Importantly, they also demonstrate that rIL-1 and TGF-beta stimulate lung fibroblast IL-6 and IL-11 production via distinct and differentially regulatable activation pathways.
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Fibroblastos/inmunología , Interleucina-11/metabolismo , Interleucina-1/farmacología , Factor de Crecimiento Transformador beta/farmacología , Calcimicina/farmacología , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Interleucina-11/genética , Ouabaína/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes/farmacología , Sistemas de Mensajero Secundario , Transducción de Señal , Acetato de Tetradecanoilforbol/farmacología , Transcripción Genética/efectos de los fármacosRESUMEN
A common side effect of radiotherapy is the development of fibrosis in the irradiated tissue. To study the mechanisms of this fibrogenic response, we developed a model system of whole-lung radiation in the rat and studied the evolution of injury by assessment of the cells and protein recovered by lavage. Once the pattern of injury was known, we attempted to modulate this reaction by administering the cytokine interferon-gamma (IFN-gamma). Rats received 15 Gy radiation to the whole thorax and were studied by lung lavage at intervals of 1 to 35 days after radiation. The effect of radiation was an initial (24 h) leak of protein, unaccompanied by cellular alterations, that resolved by 48 h. This was followed 2 wk later by a phase of inflammatory cell recruitment and more significant protein leak. A third phase of increase in inflammatory cells and further increase in protein flux was noted at Day 35. A significant cellular infiltrate was seen in lung sections obtained from animals treated in parallel experiments. IFN-gamma was given by osmotic pump from Day 0 to Day 35. This treatment significantly attenuated the PMN recruitment and protein leak (p < 0.002 and 0.01, respectively) at Days 25 and 35. Histologic sections demonstrated reduced alveolar cellularity and exudate at Day 25 (p < 0.05); however, significant numbers of inflammatory cells and exudate were present in irradiated and IFN-gamma-treated animals at Day 35. These data indicate that inflammatory cell recruitment may play a role in the lung injury following radiation. Furthermore, these preliminary data indicate that a cytokine blocks this reaction.
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Líquido del Lavado Bronquioalveolar , Interferón gamma/uso terapéutico , Neumonitis por Radiación/diagnóstico , Neumonitis por Radiación/terapia , Animales , Líquido del Lavado Bronquioalveolar/citología , Quimiotaxis de Leucocito , Pulmón/patología , Masculino , Neutrófilos/fisiología , Neumonitis por Radiación/patología , Neumonitis por Radiación/fisiopatología , Ratas , Proteínas Recombinantes , Organismos Libres de Patógenos EspecíficosRESUMEN
It has been observed widely that some individuals exposed to asbestos will experience continued losses of lung function after asbestos exposure ceases. Unfortunately, there are few data on factors that determine clinical course, limiting the clinician's ability to determine prognosis in an individual case and restricting the possibility for testing or targeting any potential intervention to alter the course among the millions at risk. In an attempt to address this question, we studied a volunteer population of 50 such men from among a stable, heterogeneous population of asbestos-exposed workers who had been continuously followed in our occupational medicine clinics for up to 12 years (mean, 6.3 years); most had some clinical or roentgenographic sign of asbestos effect, pleural or parenchymal. Each subject was reexamined clinically, functionally, and roentgenographically. Asbestos and tobacco exposure histories were carefully reviewed with the subjects and quantified based on these reports and available data regarding the various work environments from which they came. Subsequently, each underwent a bronchoalveolar lavage to assess cellularity and levels of various proteins. The levels of risk factors, clinical findings, and biologic parameters from lavage were examined for their relationship to serial changes in lung function during the period over which they had been previously followed. Results of the study demonstrate that serial changes in lung function were not closely related to level or length of prior exposure, smoking behavior, chest roentgenographic findings, or lung volumes. Progressive loss of diffusing capacity for carbon monoxide (Dco) was significantly associated with two factors: level of neutrophil concentration in lavage fluid (0.043 +/- 0.016 ml/min/mm Hg/yr drop for each 0.1 x 10(4) neutrophils per milliliter, p = 0.02) and the level of Dco itself (0.17 +/- 0.07 ml/min/mm Hg/yr drop for each 10 percent decrease in percent Dco predicted, p = 0.01). The relationship with neutrophil concentration was statistically independent of the association with Dco itself and stronger; it persisted when loss of Dco was adjusted for baseline value. Lung volume changes were not associated with any predictor variables, alone or in combination. We conclude that the presence of neutrophils in bronchoalveolar lavage fluid is associated with recent disease progression that may have implications in studies of the mechanisms of asbestos-associated disease and in clinical treatment of patients at risk.
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Asbestosis/diagnóstico , Líquido del Lavado Bronquioalveolar/citología , Neutrófilos/fisiología , Capacidad de Difusión Pulmonar/fisiología , Asbestosis/epidemiología , Asbestosis/fisiopatología , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Exposición Profesional , Pronóstico , Factores de Riesgo , Fumar/epidemiología , Factores de TiempoRESUMEN
In epidemiologic studies, airway disease and parenchymal injury are known morbid outcomes of occupational exposure to asbestos. However, the relationship of inflammatory events considered to be responsible for parenchymal injury to the subsequent development of airway injury is unknown. To assess this we performed bronchoalveolar lavage (BAL) and airway biopsies on a population of subjects with exposure to asbestos in the workplace. As an index of airway injury, we employed histologic metaplasia seen in mucosal biopsy specimens. Lung BAL fluid was analyzed for two potentially relevant protein markers and for inflammatory cells recovered from the lower respiratory tract. We related metaplasia to demographic features of this study population (eg, smoking history and asbestos exposure data) and also to the protein and cellular markers recovered by BAL. We studied 50 workers and detected keratinizing metaplasia in 15 and varying lesser abnormalities in the other 28. Cigarette smoking was not associated with the presence of metaplasia (p less than 0.2). Smoking status was associated with an increase in BAL cells (p less than 0.02); however, neither the percent nor concentration of acute inflammatory cells was significantly increased. Acute inflammatory cells (percent and cells per milliliter of BAL fluid) were significantly increased among the subjects with severe metaplasia compared with other study subjects. This increase was true of both neutrophils and eosinophils and the sum of these two (p less than 0.02). Stratification of subjects by smoking status demonstrated a persistent association of inflammatory cells with metaplasia. By logistic regression analysis, polymorphonuclear leukocytes per milliliter and eosinophils per milliliter were significantly related to the presence of metaplasia in two independent models (odds ratios, 9.9 and 7.6, respectively). Cigarette smoking and other demographic or BAL variables were not significantly associated with metaplasia in these models.
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Asbestosis/patología , Bronquios/patología , Líquido del Lavado Bronquioalveolar/citología , Asbestosis/epidemiología , Biopsia , Eosinófilos , Humanos , Metaplasia , Persona de Mediana Edad , Neutrófilos , Exposición Profesional , Análisis de Regresión , Fumar/epidemiologíaRESUMEN
Bronchoscopy and bronchoalveolar lavage (BAL) yield important information about the lower respiratory tract of subjects who have been exposed to asbestos. Evidence of metaplasia is easily detected with random biopsies in large airways and a relationship with smoking status can be found. A significant finding, however, is that inflammatory cells recovered by late BAL aliquots which presumably reflect alveolar space inflammation are also importantly associated with the presence of metaplasia. Asbestos provides an important stimulus for recruitment of inflammatory cells. These cells release oxidants which can be responsible for direct or indirect mutagenesis. Our data suggest that this inflammatory cell recruitment may be an important additional factor predictive of airway metaplasia and perhaps subsequent carcinogenesis.
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Asbestosis/patología , Bronquios/patología , Líquido del Lavado Bronquioalveolar/patología , Alveolos Pulmonares/patología , Humanos , Inflamación , Metaplasia , Neoplasias del Sistema Respiratorio/patologíaRESUMEN
To assess the role of acute inflammatory cells in large airways in the pathogenesis of metaplasia, we performed BAL (divided into aliquots) and mucosal biopsies on asbestos workers. They had evidence of asbestos-related lung injury. We found that acute inflammatory cells were significantly increased in the first aliquot. Ex-smokers had a greater percentage of PMN compared with nonsmokers and current smokers. The subjects were subgrouped with respect to biopsy-detected metaplasia. There was no difference between these groups for percentage or total number of PMN in the first aliquot. However, subjects with metaplasia had significant reduction in FEV1/FVC compared with those without. We conclude that there are significant differences in cells between the first and subsequent aliquots. Although inflammatory stimuli may be important in the pathogenesis of metaplasia, PMN present in the first aliquot could not be related to the severity of the metaplastic changes in these workers.
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Bronquios/patología , Líquido del Lavado Bronquioalveolar/patología , Animales , Asbestosis/patología , Biopsia , Humanos , Inflamación , Masculino , Metaplasia , Persona de Mediana Edad , Membrana Mucosa/patología , Neutrófilos/patología , Fumar/patologíaRESUMEN
Bronchial inflammation is associated with a reduction in airway caliber. Factors that may dampen this inflammation are ill defined. We have developed a model of airway inflammation using an extract of cotton bracts (CBE). In the current study we characterize inhibitor(s) of polymorphonuclear neutrophil (PMN) function in bronchial lavage (BL) fluid and examine the relationship between inhibitor concentrations and induction of bronchial inflammation or bronchoconstriction by CBE. We report that BL obtained contains factors that inhibit PMN hydrogen peroxide production and chemotaxis to formylmethionylleucyl-phenylalanine (FMLP). In two different subject populations the relative degree of a one molecular mass inhibitor was greatest in BL from subjects that manifested little bronchoconstriction to CBE compared with other subjects. In one subject population the relative amount of this inhibitor correlated inversely with the bronchoconstricting response to CBE and a number of parameters of airway inflammation including PMN noted on bronchial biopsy after CBE instillation. Partial chemical characterization of one molecular mass BL-derived inhibitor reveals it is of low molecular mass (less than 1,000 Da), nonpolar, and sensitive to aminopeptidase digestion. The finding that the bronchial environment contains variable concentrations of an oligopeptide that inhibits PMN function has important implications for treatment of inflammatory airway diseases.
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Bronquios/fisiología , Quimiotaxis de Leucocito , Neutrófilos/fisiología , Aminopeptidasas/farmacología , Bronquios/fisiopatología , Supervivencia Celular , Cromatografía Líquida de Alta Presión , Humanos , Técnicas In Vitro , Inflamación , Modelos Biológicos , Neutrófilos/citología , Irrigación Terapéutica , Tripsina/farmacologíaRESUMEN
The use of radiation therapy is limited by the occurrence of the potentially fatal clinical syndromes of radiation pneumonitis and fibrosis. Radiation pneumonitis usually becomes clinically apparent from 2 to 6 months after completion of radiation therapy. It is characterized by fever, cough, dyspnea, and alveolar infiltrates on chest roentgenogram and may be difficult to differentiate from infection or recurrent malignancy. The pathogenesis is uncertain, but appears to involve both direct lung tissue toxicity and an inflammatory response. The syndrome may resolve spontaneously or may progress to respiratory failure. Corticosteroids may be effective therapy if started early in the course of the disease. The time course for the development of radiation fibrosis is later than that for radiation pneumonitis. It is usually present by 1 year following irradiation, but may not become clinically apparent until 2 years after radiation therapy. It is characterized by the insidious onset of dyspnea on exertion. It most often is mild, but can progress to chronic respiratory failure. There is no known successful treatment for this condition.
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Fibrosis Pulmonar/etiología , Traumatismos por Radiación , Animales , Humanos , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/terapia , Traumatismos Experimentales por Radiación , Radioterapia/efectos adversos , Síndrome , Factores de TiempoRESUMEN
Glutathione is a tripeptide important in a number of diverse cellular functions including enzymatic reactions involved in prostaglandin endoperoxide metabolism. We have previously reported that cyclophosphamide administration to rats results in acute lung injury manifested by increased bronchoalveolar lavage albumin concentrations. In the current study we examine whether cyclophosphamide treatment affects pulmonary glutathione stores or bronchoalveolar endoperoxide metabolic product levels and whether these effects may be related to acute lung injury caused by the drug. We show that cyclophosphamide treatment causes a dose-dependent reduction in pulmonary glutathione stores 4 h after drug administration. In addition, acute lung injury as the result of cyclophosphamide can be abrogated by coadministration of oxothiazolidine carboxylate, an intracellular cysteine delivery system that also reverses pulmonary glutathione depletion induced by cyclophosphamide in our study. Finally, cyclophosphamide treatment reduces prostaglandin E2 concentrations in bronchoalveolar lavage and alveolar macrophage culture supernatant in a dose-dependent fashion and increases bronchoalveolar thromboxane concentrations in low dose-treated animals. These effects are reversed to a variable degree by coadministration of oxothiazolidine carboxylate. Our study suggests in vivo pulmonary arachidonic acid metabolism and cyclophosphamide-induced acute lung injury are modulated by cellular glutathione stores. These findings may have important implications for the treatment of acute lung injury.
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Ciclofosfamida/toxicidad , Glutatión/metabolismo , Lesión Pulmonar , Endoperóxidos de Prostaglandina/metabolismo , Animales , Líquido del Lavado Bronquioalveolar/análisis , Líquido del Lavado Bronquioalveolar/citología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Endoperóxidos de Prostaglandina/análisis , Ácido Pirrolidona Carboxílico , Ratas , Ratas Endogámicas F344 , Tiazoles/farmacología , TiazolidinasRESUMEN
Heart-lung transplant recipients represent a unique population who experience episodic lung injury caused by infection or rejection. We hypothesized that the proteins in the respiratory lining fluids of these patients might reflect and provide insights into the in vivo immunologic and inflammatory events that occur in the transplanted lung. Structural, inflammatory, and immune proteins were quantitated in 57 samples of BAL fluid recovered from 17 heart-lung recipients when infections, rejection, or neither was present. Protein levels were compared with those of normal subjects and between the clinical transplant groups. When neither infection nor rejection was present, levels of albumin, fibronectin, and immunoglobulins G, M, and A were all higher in the transplanted lungs as compared with the normal lungs. These findings suggest that a new steady state of these proteins is established in the transplanted lungs. When infection or rejection was present, there was a further significant increase in albumin, fibronectin, IgG, and especially C5a in the transplanted lungs. These findings suggest that at least some elements of host defense remain intact in the posttransplantation period despite the use of immunosuppressive drugs and a HLA-incompatible microenvironment. The profiles of recovered alveolar proteins did not, however, help to differentiate infection from rejection. This is disappointing because distinguishing between infection and rejection without examination of lung tissue remains an unresolved and important clinical problem. Nevertheless these data provide new insights into organ tolerance and defense of the newly transplanted lung from infection or rejection.