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Comparison Of Eight Prosthetic Aortic Valves In A Cadaver Model., Benjamin A. Youdelman, Hitoshi Hirose, Harsh Jain, J Yasha Kresh, John W.C. Entwistle, Andrew S. Wechsler

Department of Surgery Faculty Papers

OBJECTIVES: Proper valve selection is critical to ensure appropriate valve replacement for patients, because implantation of a small valve might place the patient at risk for persistent gradients. Labeled valve size is not the same as millimeter measure of prosthetic valve diameters or the annulus into which it will fit. Studies that use the labeled valve size in lieu of actual measured diameter in millimeters to compare different valves might be misleading. Using human cadaver hearts, we sized the aortic annulus with 8 commonly used prosthetic aortic valve sizers and compared the valves using geometric orifice area. This novel method …

Neurogranin Controls The Spatiotemporal Pattern Of Postsynaptic Ca2+/Cam Signaling, Yoshihisa Kubota, John A Putkey, M Neal Waxham

Journal Articles

Neurogranin (Ng) is a postsynaptic IQ-motif containing protein that accelerates Ca(2+) dissociation from calmodulin (CaM), a key regulator of long-term potentiation and long-term depression in CA1 pyramidal neurons. The exact physiological role of Ng, however, remains controversial. Two genetic knockout studies of Ng showed opposite outcomes in terms of the induction of synaptic plasticity. To understand its function, we test the hypothesis that Ng could regulate the spatial range of action of Ca(2+)/CaM based on its ability to accelerate the dissociation of Ca(2+) from CaM. Using a mathematical model constructed on the known biochemistry of Ng, we calculate the cycle …

Relationships Between Scores On The Jefferson Scale Of Physician Empathy, Patient Perceptions Of Physician Empathy, And Humanistic Approaches To Patient Care: A Validity Study., Karen M. Glaser, Fred W. Markham, Herbert M. Adler, Patrick R. Mcmanus, Mohammadreza Hojat

Department of Psychiatry and Human Behavior Faculty Papers

BACKGROUND: Empathy is the backbone of a positive physician-patient relationship. Physician empathy and the patient's awareness of the physician's empathic concern can lead to a more positive clinical outcome.

MATERIAL/METHODS: The Jefferson Scale of Physician Empathy (JSPE) was completed by 36 physicians in the Family Medicine residency program at Thomas Jefferson University Hospital, and 90 patients evaluated these physicians by completing the Jefferson Scale of Patient Perceptions of Physician Empathy (JSPPPE), and a survey about physicians' humanistic approaches to patient care.

RESULTS: A statistically significant correlation was found between scores of the JSPE and JSPPPE (r=0.48, p

CONCLUSIONS: These findings …

Mechanisms Of Perceptual Learning Of Depth Discrimination In Random Dot Stereograms, Liat Gantz, Saumil S Patel, Susana T L Chung, Ronald S Harwerth

Journal Articles

Perceptual learning is a training induced improvement in performance. Mechanisms underlying the perceptual learning of depth discrimination in dynamic random dot stereograms were examined by assessing stereothresholds as a function of decorrelation. The inflection point of the decorrelation function was defined as the level of decorrelation corresponding to 1.4 times the threshold when decorrelation is 0%. In general, stereothresholds increased with increasing decorrelation. Following training, stereothresholds and standard errors of measurement decreased systematically for all tested decorrelation values. Post training decorrelation functions were reduced by a multiplicative constant (approximately 5), exhibiting changes in stereothresholds without changes in the inflection points. …

Comparison Of Alternative Models For Personality Disorders, Leslie C. Morey, Christopher J. Hopwood, John G. Gunderson, Andrew E. Skodol, M. Tracie Shea, Shirley Yen, Robert L. Stout, Mary C. Zanarini, Carlos M. Grilo, Charles A. Sanislow, Thomas H. Mcglashan

Charles A. Sanislow, Ph.D.

BACKGROUND: The categorical classification system for personality disorder (PD) has been frequently criticized and several alternative dimensional models have been proposed.

METHOD: Antecedent, concurrent and predictive markers of construct validity were examined for three models of PDs: the Five-Factor Model (FFM), the Schedule for Nonadaptive and Adaptive Personality (SNAP) model and the DSM-IV in the Collaborative Study of Personality Disorders (CLPS) sample.

RESULTS: All models showed substantial validity across a variety of marker variables over time. Dimensional models (including dimensionalized DSM-IV) consistently outperformed the conventional categorical diagnosis in predicting external variables, such as subsequent suicidal gestures and hospitalizations. FFM facets …

Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne

Journal Articles

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop …

The Expression Of Ovine Placental Lactogen, Star And Progesterone-Associated Steroidogenic Enzymes In Placentae Of Overnourished Growing Adolescent Ewes., Richard G Lea, Peter Wooding, Ian Stewart, Lisa T Hannah, Stephen Morton, Karen Wallace, Raymond P Aitken, John S Milne, Timothy Regnault, Russell V Anthony, Jacqueline M Wallace

Paediatrics Publications

Overnourishing pregnant adolescent sheep promotes maternal growth but reduces placental mass, lamb birth weight and circulating progesterone. This study aimed to determine whether altered progesterone reflected transcript abundance for StAR (cholesterol transporter) and the steroidogenic enzymes (Cyp11A1, Hsd3b and Cyp17). Circulating and placental expression of ovine placental lactogen (oPL) was also investigated. Adolescent ewes with singleton pregnancies were fed high (H) or moderate (M) nutrient intake diets to restrict or support placental growth. Experiment 1: peripheral progesterone and oPL concentrations were measured in H (n=7) and M (n=6) animals across gestation (days 7-140). Experiment 2: progesterone was measured to mid- …

Direct Visualization Of The Putative Portal In The Kaposi's Sarcoma-Associated Herpesvirus Capsid By Cryoelectron Tomography, Binbin Deng, Christine M O'Connor, Dean H Kedes, Z Hong Zhou

Journal Articles

Genetic and biochemical studies have suggested the existence of a bacteriophage-like, DNA-packaging/ejecting portal complex in herpesviruses capsids, but its arrangement remained unknown. Here, we report the first visualization of a unique vertex in the Kaposi's sarcoma-associated herpesvirus (KSHV) capsid by cryoelectron tomography, thus providing direct structural evidence for the existence of a portal complex in a gammaherpesvirus. This putative KSHV portal is an internally localized, umbilicated structure and lacks all of the external machineries characteristic of portals in DNA bacteriophages.

Crystal Structure Of The Anabaena Sensory Rhodopsin Transducer, Lutz Vogeley, Vishwa D Trivedi, Oleg A Sineshchekov, Elena N Spudich, John L Spudich, Hartmut Luecke

Journal Articles

We present crystal structures of the Anabaena sensory rhodopsin transducer (ASRT), a soluble cytoplasmic protein that interacts with the first structurally characterized eubacterial retinylidene photoreceptor Anabaena sensory rhodopsin (ASR). Four crystal structures of ASRT from three different spacegroups were obtained, in all of which ASRT is present as a planar (C4) tetramer, consistent with our characterization of ASRT as a tetramer in solution. The ASRT tetramer is tightly packed, with large interfaces where the well-structured beta-sandwich portion of the monomers provides the bulk of the tetramer-forming interactions, and forms a flat, stable surface on one side of the tetramer (the …

The Nestin Progenitor Lineage Is The Compartment Of Origin For Pancreatic Intraepithelial Neoplasia, Catherine Carriere, Elliot S. Seeley, Tobias Goetze, Daniel S. Longnecker, Murray Korc

Dartmouth Scholarship

To determine the cell compartment in which initial oncogenic mutations occur in pancreatic ductal adenocarcinoma (PDAC), we generated a mouse model in which endogenous expression of mutated Kras (Kras(G12D)) was initially directed to a population of pancreatic exocrine progenitors characterized by the expression of Nestin. Targeting of oncogenic Kras to such a restricted cell compartment was sufficient for the formation of pancreatic intraepithelial neoplasias (PanINs), putative precursors to PDAC. PanINs appeared with the same grade and frequency as observed when Kras(G12D) was targeted to the whole pancreas by a Pdx1-driven Cre recombinase strategy. Thus, the Nestin cell lineage is highly …