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David Stevens

Publications and source records attributed to David Stevens.

9 recordsLinked to original sources
PubMed2006

"Oh! She doesn't speak English!" Assessing resident competence in managing linguistic and cultural barriers.

BACKGROUND: Residents must master complex skills to care for culturally and linguistically diverse patients. METHODS: As part of an annual 10-station, standardized patient (SP) examination, medical residents interacted with a 50-year-old reserved, Bengali-speaking woman (SP) with a positive fecal occult blood accompanied by her bilingual brother (standardized interpreter (SI)). While the resident addressed the need for a colonoscopy, the SI did not translate word for word unless directed to, questioned medical terms, and was reluctant to tell the SP frightening information. The SP/SI, faculty observers, and the resident assessed the performance. RESULTS: Seventy-six residents participated. Mean faculty ratings (9-point scale) were as follows: overall 6.0, communication 6.0, knowledge 6.3. Mean SP/SI ratings (3.1, range 1.9 to 3.9) correlated with faculty ratings (overall r=.719, communication r=.639, knowledge r=.457, all P<.01). Internal reliability as measured by Cronbach's alpha coefficients for the 20 item instrument was 0.91. Poor performance on this station was associated with poor performance on other stations. Eighty-nine percent of residents stated that the educational value was moderate to high. CONCLUSION: We reliably assessed residents communication skills conducting a common clinical task across a significant language barrier. This medical education innovation provides the first steps to measuring interpreter facilitated skills in residency training.

Attitude of Health Personnel↗
PubMed2005

The role of Snapin in neurosecretion: snapin knock-out mice exhibit impaired calcium-dependent exocytosis of large dense-core vesicles in chromaffin cells.

Identification of the molecules that regulate the priming of synaptic vesicles for fusion and the structural coupling of the calcium sensor with the soluble N-ethyl maleimide sensitive factor adaptor protein receptor (SNARE)-based fusion machinery is critical for understanding the mechanisms underlying calcium-dependent neurosecretion. Snapin binds to synaptosomal-associated protein 25 kDa (SNAP-25) and enhances the association of the SNARE complex with synaptotagmin. In the present study, we abolished snapin expression in mice and functionally evaluated the role of Snapin in neuroexocytosis. We found that the association of synaptotagmin-1 with SNAP-25 in brain homogenates of snapin mutant mice is impaired. Consequently, the absence of Snapin in embryonic chromaffin cells leads to a significant reduction of calcium-dependent exocytosis resulting from a decreased number of vesicles in releasable pools. Overexpression of Snapin fully rescued this inhibitory effect in the mutant cells. Furthermore, Snapin is relatively enriched in the purified large dense-core vesicles of chromaffin cells and associated with synaptotagmin-1. Thus, our biochemical and electrophysiological studies using snapin knock-out mice demonstrate that Snapin plays a critical role in modulating neurosecretion by stabilizing the release-ready vesicles.

Animals↗
PubMed2004

Heterozygous telomerase RNA mutations found in dyskeratosis congenita and aplastic anemia reduce telomerase activity via haploinsufficiency.

Mutations in TERC, encoding the RNA component of telomerase, have been found in autosomal dominant dyskeratosis congenita (DC) and aplastic anemia (AA). Several polymorphisms also exist in the TERC gene, making functional testing of potential pathogenic mutations essential. Here, we have tested normal and mutant TERC molecules in 2 telomerase reconstitution assays, 1 in vitro and 1 in transfected telomerase-negative cells. We find that 2 polymorphic mutations G58A and G228A have no effect on telomerase activity in these assays, whereas 6 mutations found in DC and AA cause reduction or abolition of telomerase activity. Mutations in the pseudoknot region of the TERC molecule, C72G, 96-7DeltaCT, GC107-8AG and 110-3DeltaGACT reduce the catalytic activity of reconstituted telomerase, whereas mutations in the 3' portion of the molecule C408G and a deletion of the 3' 74 bases have normal activity in vitro but reduced intracellular activity. By analyzing second site mutations that recreate regions of secondary structure but retain the pathogenic mutations we show that mutations C72G, GC107-8AG, and C408G act by disrupting the secondary structure or folding of TERC. Finally, experiments reconstituting telomerase with both normal and mutant TERC molecules suggest the mutations act via haploinsufficiency rather than by a dominant-negative mechanism.

Adult↗
PubMed2003

Medical humanities at New York University School of Medicine: an array of rich programs in diverse settings.

The New York University School of Medicine has a rich tradition of cultivating programs in medical humanities and professionalism. They are drawn from the departments, centers, students, and faculty in the School of Medicine, have linkages throughout the university, and are interwoven into the fabric and culture of the institution. Some are centrally based in the School of Medicine's deans' office, and others are located in individual departments and receive support from the dean's office. This article describes representative programs for medical students and faculty. Curricular initiatives, the fundamental components of medical students' learning, include a course entitled "The Physician, Patient, and Society," a clerkship essay in the Medicine Clerkship, an opportunity for reflection during the medicine clerkship, and a medical humanities elective. In 2002, the Professionalism Initiative was launched to enhance and reflect the values of the medical profession. Its curriculum consists of a series of events that coordinate, particularly, with existing elements of the first-year curriculum (e.g., orientation week, a session during anatomy, a self-assessment workshop, and a peer-assessment workshop). The Master Scholars Program is a group of five, theme-based master societies consisting of faculty and students who share common interests around the society's themes. Programs developed for the societies include colloquia, faculty-led seminars, a mandatory student-mentoring program, and visiting scholars. Finally, the authors describe three high-quality literary publications created at New York University School of Medicine. Each of the initiatives undergoes regular critical examination and reflection that drive future planning.

Clinical Clerkship↗
PubMed2002

Deletion of leucine 61 in glucose-6-phosphate dehydrogenase leads to chronic nonspherocytic anemia, granulocyte dysfunction, and increased susceptibility to infections.

In this study the blood cells of 4 male patients from 2 unrelated families with chronic nonspherocytic anemia and recurrent bacterial infections were investigated. The activity of glucose-6- phosphate dehydrogenase (G6PD) in the red blood cells and in the granulocytes of these patients was below detection level. Moreover, their granulocytes displayed a decreased respiratory burst upon activation. Sequencing of genomic DNA revealed a novel 3-base pair (TCT) deletion in the G6PD gene, predicting the deletion of a leucine at position 61. The mutant G6PD protein was undetectable by Western blotting in the red blood cells and granulocytes of these patients. In phytohemagglutinin-stimulated lymphocytes the G6PD protein was present, but the amount of G6PD protein was strongly diminished in the patients' cells. Purified mutant protein from an Escherichia coli expression system showed decreased heat stability and decreased specific activity. Furthermore, we found that the messenger RNA of G6PD(180-182delTCT) is unstable, which may contribute to the severe G6PD deficiency observed in these patients. We propose the name "G6PD Amsterdam" for this new variant.

Adolescent↗
PubMed2002

Absence of mutations in the HoxA10, HoxA11 and HoxD11 nucleotide coding sequences in thrombocytopenia with absent radius syndrome.

Recent studies have suggested the HoxA10, HoxA11 and HoxD11 homeobox genes as candidate loci for the thrombocytopenia with absent radius (TAR) syndrome. For example, targeted disruptions of these Hox genes result in abnormal development of the mouse radius, while overexpression of HoxA10 stimulates mouse megakaryocyte (MK) development in vitro. To examine the expression of Hox genes in human MK cells, we utilized reverse transcription polymerase chain reaction with degenerate oligonucleotides to study megakaryocytic cell lines (MEG-01, DAMI), and primary human MK purified from adult and cord blood. Using this approach, 13 out of 40 clones isolated from cell lines, 10 out of 21 from cord MK, and 11 out of 21 from adult MK were identified as HoxA10, while HoxA11 and HoxD11 sequences were not detected. The normal genomic sequences for the human HoxA10, -A11, and -D11 genes were then determined and sequenced in 10 unrelated individuals with TAR syndrome. In all patients the derived amino acid sequence for the three Hox genes was identical to normal controls. Southern blotting did not reveal genomic rearrangements or deletions at these loci, and in two patients intact HoxA10 transcripts were detected by amplification in myeloid cells. Although these studies cannot completely exclude the possibility that the TAR syndrome results from non-coding mutations that affect the level of Hox gene expression in megakaryocytes, mutations in the coding sequence of the Hox genes known to affect radial development are not a common cause of TAR syndrome.

Adolescent↗
PubMed2002

Memory, neurodynamics, and human relationships.

In this article we discuss the implications of the functional organization and dynamics of the brain for understanding human relationships. In particular, we focus on the brain's multiple memory systems and the various roles they play in organizing the interactions of people as they come to know one another. The distinction between the relatively independent declarative, procedural, and emotional learning systems is especially significant in this regard, as the former mediates what we know about one another, the second mediates what we do with one another, and the third affects behavior by altering our emotional state. Knowledge of the functioning of these dissociable memory systems provides a novel perspective on relationships--both ordinary social relationships and those that develop in psychotherapy--and further illuminates psychotherapeutic transference and countertransference phenomena. We begin with a review of the neural basis of these processes, then turn our attention to the interpersonal level of analysis.

Brain↗
PubMedDate not supplied

Risk of refracture through unicameral bone cysts of the proximal femur.

The authors determined the results after traction or traction and hip spica treatment of the initial fractures through unicameral bone cysts of the proximal femur in 20 children. All of the eight displaced fractures healed, but with coxa vara and avascular necrosis in one, coxa vara in a second, and coxa breva in a third. Spontaneous healing of the cyst occurred in three of the eight children; satisfactory healing was achieved and maintained after intralesional corticosteroid injections in four of the eight children. In the remaining child with a displaced fracture, reactivation of the cyst and exercise-related pain, indicative of an incipient refracture, occurred 3 years after initial presentation. All of the 12 undisplaced fractures healed without deformity or avascular necrosis. Intralesional corticosteroids were used in all of the 12 children because none of them showed spontaneous healing of their cysts. Satisfactory radiographic healing was achieved 1 year after presentation in all of the 12 children. However, one or more refractures resulting from reactivation of the cyst occurred in 6 of the 12 children 2 to 5 years after initial presentation. The results of this study indicate that satisfactory radiographic healing needs to be achieved by the end of the first year and needs to be maintained thereafter to prevent refractures.

Adolescent↗