Recent Publications by CFE Educators

Regulated gene expression will provide important platforms from which gene functions can be investigated and safer means of gene therapy may be developed. Histone deacetylases have recently been shown to play an important role in regulating gene expression. Here we investigated whether a more tightly controlled expression could be achieved by using a novel chimeric repressor that recruits histone deacetylases to a tetracycline-responsive promoter. This chimeric repressor was engineered by fusing the tetracycline repressor (TetR) with an mSin3-interacting domain of human Mad1 and was shown to bind the tetO(2) element with high affinity, and its binding was efficiently abrogated by doxycycline. The chimeric repressor was shown to directly interact with mSin3 of the histone deacetylase complex. This inducible system was further simplified by using a single vector that contained both a chimeric repressor expression cassette and a tetracycline-responsive promoter. When transiently introduced into mammalian cells, the chimeric repressor system exhibited a significantly lower basal level of luciferase activity (up to 25-fold) than that of the TetR control. When stably transfected into HEK 293 cells, the chimeric repressor system was shown to exert a tight control of green fluorescent protein expression in a doxycycline dose- and time-dependent fashion. Therefore, this novel chimeric repressor provides an effective means for more tightly regulated gene expression, and the simplified inducible system may be used for a broad range of basic and clinical studies.

Our purpose was to identify clinical, radiological and physiological (CRP) determinants of survival and to develop a CRP scoring system that predicts survival in newly diagnosed cases of idiopathic pulmonary fibrosis (IPF). The study population consisted of 238 patients with biopsy confirmed usual interstitial pneumonia. For each patient, clinical manifestations, chest radiographs, and pulmonary physiology were prospectively assessed. We used Cox proportional-hazards models to assess the effect of these parameters on survival. The effects of age and smoking were included in the analysis. Survival was related to age, smoking status (longer in current smokers), clubbing, the extent of interstitial opacities and presence of pulmonary hypertension on the chest radiograph, reduced lung volume, and abnormal gas exchange during maximal exercise. A mathematical CRP score for predicting survival was derived from these parameters. We showed that this CRP score correlated with the extent and severity of the important histopathologic features of IPF, i.e., fibrosis, cellularity, the granulation/connective tissue deposition, and the total pathologic derangement. Using these models, clinicians are in a better position to provide prognostic information to patients with IPF and to improve the selection of the most appropriate patients for lung transplantation or other standard or novel therapeutic interventions.

It is hypothesized that the extent and severity of fibrosis and cellularity found on lung biopsy determine the prognosis and response to therapy in idiopathic pulmonary fibrosis (IPF). The objective of this study was to determine which histopathologic features predict survival in IPF. We prospectively studied 87 patients with usual interstitial pneumonia (UIP) confirmed by surgical lung biopsy. Four pathologists independently graded the extent and severity of specific histopathologic features. We used Cox proportional-hazards models to assess the effect of histopathologic patterns on patients' survival. The effects of age, sex, and smoking were also included in the analysis. Sixty-three patients died during the 17-yr study period. Survival was longer in subjects with lesser degrees of granulation/connective tissue deposition (fibroblastic foci). The degree of alveolar space cellularity, alveolar wall fibrosis, and cellularity did not affect survival. A history of cigarette smoking, the level of dyspnea, and the degree of lung stiffness at presentation were also shown to be independent factors predicting survival. The extent of fibroblastic foci present on lung biopsy predicts survival in IPF. These findings support the hypothesis that the critical pathway to end-stage fibrosis is not "alveolitis" but rather the ongoing epithelial damage and repair process associated with persistent fibroblastic proliferation. Controlling these processes, rather than stopping inflammation, appears most important in preventing progressive disease and the fatal outcome common in IPF.

The sensation of pain alerts us to real or impending injury and triggers appropriate protective responses. Unfortunately, pain often outlives its usefulness as a warning system and instead becomes chronic and debilitating. This transition to a chronic phase involves changes within the spinal cord and brain, but there is also remarkable modulation where pain messages are initiated - at the level of the primary sensory neuron. Efforts to determine how these neurons detect pain-producing stimuli of a thermal, mechanical or chemical nature have revealed new signalling mechanisms and brought us closer to understanding the molecular events that facilitate transitions from acute to persistent pain.

OBJECTIVE

The One-Minute Preceptor (OMP) model of faculty development is used widely to improve teaching, but its effect on teaching behavior has not been assessed. We aim to evaluate the effect of this intervention on residents' teaching skills.

DESIGN

Randomized controlled trial.

SETTING

Inpatient teaching services at both a tertiary care hospital and a Veterans Administration Medical Center affiliated with a University Medical Center.

PARTICIPANTS

Participants included 57 second- and third-year internal medicine residents that were randomized to the intervention group (n = 28) or to the control group (n = 29).

INTERVENTION

The intervention was a 1-hour session incorporating lecture, group discussion, and role-play.

MEASUREMENTS AND MAIN RESULTS

Primary outcome measures were resident self-report and learner ratings of resident performance of the OMP teaching behaviors. Residents assigned to the intervention group reported statistically significant changes in all behaviors (P .05). Eighty-seven percent of residents rated the intervention as "useful or very useful" on a 1-5 point scale with a mean of 4.28. Student ratings of teacher performance showed improvements in all skills except "Teaching General Rules." Learners of the residents in the intervention group reported increased motivation to do outside reading when compared to learners of the control residents. Ratings of overall teaching effectiveness were not significantly different between the 2 groups.

CONCLUSIONS

The OMP model is a brief and easy-to-administer intervention that provides modest improvements in residents' teaching skills.

For many years, the clinical entity of idiopathic interstitial pneumonia (IIP) has been a source of confusion for physicians. There has been much debate over the utility of subclassifying this condition histopathologically. It now appears that such classification is useful, and the most important distinction is the presence or absence of usual interstitial pneumonia (UIP). Unlike the other histopathologic subgroups, UIP has a grave prognosis and responds poorly to traditional therapies. To emphasize this clinical difference, the diagnosis of idiopathic pulmonary fibrosis (IPF), once used synonymously with IIP, is now reserved for only those patients with the histopathologic pattern of UIP. Although the gold standard for the diagnosis of IPF/UIP remains surgical lung biopsy, recent studies suggest that careful clinical and radiographic evaluation can identify IPF/UIP with a specificity of 90% or more. In the absence of a clear clinical diagnosis, we recommend pursuing surgical lung biopsy. Knowledge of the underlying histopathology will allow for more accurate prognosis, help guide therapy, and make possible the clinical investigation of novel therapeutic agents for patients with IIP.