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D P Regula

Publications and source records attributed to D P Regula.

9 recordsLinked to original sources

A pilot study of faculty development for basic science teachers.

PURPOSE: Relatively little research has focused on faculty development methods that assist basic science teachers to improve their instructional skills. This study was designed to assess the effectiveness for basic science faculty of a faculty development seminar series that had been previously shown useful for clinical teachers. METHOD: The Stanford Faculty Development Program's seminars on clinical teaching were adapted for basic science instruction. Eight pathology faculty participated in a series of nine small-group seminars designed to provide teachers with knowledge of a framework for analyzing teaching and identifying areas for improvement, and skill-based training in specific teaching behaviors. Each seminar included (1) brief lectures, (2) review of videotaped reenactments of teaching interactions, (3) role-play exercises with videotape review, and (4) formulation of personal and departmental teaching goals. RESULTS: Program evaluation included multiple measures: participant self-assessment, student ratings of the participants, and blinded ratings of pre- and post-seminar videotapes of participants' classroom teaching. All measures indicated a positive effect of the intervention. CONCLUSION: Faculty development programs have significant potential to enhance basic science instructors' teaching effectiveness.

Adult↗

Targeted disruption of the mouse beta1-adrenergic receptor gene: developmental and cardiovascular effects.

At least three distinct beta-adrenergic receptor (beta-AR) subtypes exist in mammals. These receptors modulate a wide variety of processes, from development and behavior, to cardiac function, metabolism, and smooth muscle tone. To understand the roles that individual beta-AR subtypes play in these processes, we have used the technique of gene targeting to create homozygous beta 1-AR null mutants (beta 1-AR -/-) in mice. The majority of beta 1-AR -/- mice die prenatally, and the penetrance of lethality shows strain dependence. Beta l-AR -/- mice that do survive to adulthood appear normal, but lack the chronotropic and inotropic responses seen in wild-type mice when beta-AR agonists such as isoproterenol are administered. Moreover, this lack of responsiveness is accompanied by markedly reduced stimulation of adenylate cyclase in cardiac membranes from beta 1-AR -/- mice. These findings occur despite persistent cardiac beta 2-AR expression, demonstrating the importance of beta 1-ARs for proper mouse development and cardiac function, while highlighting functional differences between beta-AR subtypes.

Adenylyl Cyclases↗

Epstein-Barr virus-associated natural killer-large granular lymphocyte leukemia.

We describe the first case of an Epstein-Barr virus (EBV)-associated natural killer-large granular lymphocyte (NK-LGL) leukemia in the United States to the best of our knowledge. A 29-year-old woman of Japanese descent developed EBV infection after a blood transfusion as indicated by a rise in serum antibody titers. Peripheral blood and bone marrow aspirate smears demonstrated increased LGLs. Flow cytometry showed that these cells expressed NK-associated surface antigens. Cytogenetic analysis of the bone marrow aspirate showed two distinct but related clones with multiple copies of a modified 7 marker chromosome. Death followed colonic perforation. Findings at necropsy included bone marrow lymphocytosis and erythrophagocytosis, a mononucleosis-like lymphadenitis, atypical hepatitis with a mixed, predominantly T-cell infiltrate, interstitial pneumonitis, and multiorgan system vasculitis with perforation of the transverse colon. Epstein-Barr virus transcripts were identified in lymphocytes infiltrating liver and peripheral nerve by in situ hybridization. In addition, Southern blot analyses showed monoclonal bands superimposed on oligoclonal ladders of EBV termini in liver and lymph node. The identical episomal form of EBV was found in the bone marrow, lymph node, and liver. No immunoglobulin (Ig), T-cell receptor beta, or T-cell receptor gamma chain gene rearrangements were identified. These studies support the hypothesis that the LGL population was a neoplastic EBV-related clonal proliferation of NK cells.

Adult↗

Effects of an isogenic Zn-metalloprotease-deficient mutant of Legionella pneumophila in a guinea-pig pneumonia model.

To determine the effects, if any, of the Zn-metalloprotease on virulence of Legionella pneumophila infection, an isogenic mutant deficient in protease (encoded by the proA gene) was tested in an Acanthamoeba cell model, in guinea-pig macrophages, and in a guinea-pig pneumonia model. The cloned proA gene was completely inactivated by insertion of a kanamycin-resistance cassette into the protease gene of L. pneumophila AA100. This mutated gene was then introduced into the L. pneumophila chromosome by allelic exchange to form the isogenic ProA- mutant AA200. AA200 showed no difference in its ability to enter, survive, or grow in Acanthamoeba and explanted guinea-pig macrophages; neither light nor electron microscopy revealed morphological differences in the eukaryotic cells infected with the protease mutant or the wild-type strains. The proA gene was found to be expressed in L. pneumophila during intracellular growth in amoebae by measuring the light produced from a truncated luxC gene fusion with the proA promoter. Virulence of the protease mutant was attenuated when tested in a guinea-pig model of infection employing the intratracheal inoculation method. AA200 was slower to cause death, grew to lower numbers in the lungs, resulted in less necrotic debris and a larger macrophage infiltrate, and was more likely to be found in association with macrophage vacuoles than the parent strain. Although deletion of the protease was not sufficient to completely abolish virulence in a guinea-pig model, the mutation caused a delay in the lethal effects of L. pneumophila and attenuated the infection.

Acanthamoeba↗

Autopsy findings after coronary rotational atherectomy.

We describe the findings at autopsy in a patient who underwent Rotablator atherectomy of the right coronary artery. During the procedure, the artery became occluded. Despite attempts to reopen the vessel with balloon angioplasty and emergency coronary artery bypass grafting, the patient developed irreversible cardiac failure and expired 2 days after the Rotablator procedure. At autopsy, the right coronary artery was found to be occluded by thrombus. No evidence of dissection or perforation of the vessel wall was seen. Small intramyocardial arteries and arterioles, downstream from the treated vessel, were embolized by pulverized atheroma.

Angioplasty, Balloon, Coronary↗

Nodular and diffuse types of lymphocyte predominance Hodgkin's disease.

The nodular form of lymphocyte predominance Hodgkin's disease has been shown to be immunophenotypically distinct from the histologically diffuse form and from other types of Hodgkin's disease. We undertook a clinicopathological study of 73 cases to determine whether any clinical differences between the nodular and diffuse subtypes could be discerned. Patients with the diffuse form (n = 41) tended to have a course similar to that of other types of Hodgkin's disease; there were few relapses and only two deaths due to Hodgkin's disease. In contrast, patients with the nodular form (n = 32) had significantly more relapses, which were independent of stage or treatment and equally distributed up to 10 years after initial therapy. Despite the frequent relapses, patients with the nodular form had an indolent course, and there was only one death due to Hodgkin's disease. There were seven fatal second cancers and two non-neoplastic treatment-related deaths, equally distributed between the nodular and diffuse groups. We conclude that nodular lymphocyte predominance Hodgkin's disease may have important clinical as well as immunophenotypic differences from other forms of Hodgkin's disease, and that patients with this condition should be followed carefully because of the possibility of late relapse.

Adolescent↗

Lymphocyte predominance Hodgkin's disease: a reappraisal based upon histological and immunophenotypical findings in relapsing cases.

The clinical, morphological and immunological findings in nine cases of relapsing lymphocyte predominance Hodgkin's disease (LPHD) are examined. Six patients had initial biopsies demonstrating nodular lymphocytic and/or histiocytic (L&H) LPHD; Leu-M1 was not expressed by any of the atypical cells in these cases. All six demonstrated one or more recurrences of nodular L & H LPHD; four are currently free of disease, one died of non-Hodgkin's lymphoma and another died of leukaemia. Two patients had initial biopsies demonstrating diffuse LPHD, with only rare multilobated atypical cells (L & H variants). Both patients had recurrences interpreted as mixed cellularity Hodgkin's disease, 10 and 15 years after initial therapy and both died with lymphocyte depleted Hodgkin's disease. The atypical cells in the initial biopsies and in subsequent recurrences failed to express Leu-M1, but did express leukocyte common antigen. The initial biopsy from the final patient was histologically interpreted as focal involvement by LPHD, but interfollicular Hodgkin's disease was considered after the Leu-M1 stain revealed additional atypical cells. The disease relapsed and the patient died with typical nodular sclerosing Hodgkin's disease. The pattern of the relapses supports the concept that the histological entity of LPHD may include several distinct clinicopathological subgroups.

Biopsy↗