Biomedical subjects

Neri M Cohen

Publications and source records attributed to Neri M Cohen.

5 recordsLinked to original sources

PubMed2004

Neutralizing endogenous IL-6 renders mast cells of the MCT type from lung, but not the MCTC type from skin and lung, susceptible to human recombinant IL-4-induced apoptosis.

Human cord blood-derived mast cells undergo apoptosis upon exposure to recombinant human (rh)IL-4 and become resistant to rhIL-4-induced apoptosis when cultured in the presence of rhIL-6. The current study extends these effects of rhIL-4 to different populations of human mast cells, namely fetal liver-derived mast cells, lung-derived mast cells, and skin-derived mast cells. Endogenous production of IL-6 appears to protect fetal liver-derived mast cells and those of the MC(T) phenotype from rhIL-4-mediated apoptosis, because neutralization of IL-6 renders these mast cells sensitive. In contrast, mast cells of the MC(TC) phenotype from skin and lung were resistant to IL-4-mediated apoptosis, even after neutralization of endogenous IL-6. MC(TC) cells were CD124(low), whereas those of the MC(T) cells were CD124(high). These observations extend the phenotypic differences between MC(T) and MC(TC) types of human mast cells to include different functional responses to IL-4.

Antibodies, Monoclonal↗

PubMed2004

Implementing the ACGME general competencies in a cardiothoracic surgery residency program using 360-degree feedback.

BACKGROUND: Methods to assess the six competency categories outlined by the Accreditation Council on Graduate Medical Education are essential to allow residency programs to develop reproducible evaluations of their educational curriculum. Current tools to evaluate competencies are insufficient to perform these tasks, particularly in subspecialty disciplines. The key objective of this initiative was to develop and implement an evaluative tool that would provide data to residents and program leadership regarding their performance and to provide the training program with a reliable way to assess this component of the program. METHODS: Utilizing a highly customized survey tool with a group of cardiothoracic residents, we implemented a 360-degree performance assessment process based on the six Accreditation Council on Graduate Medical Education competency areas. The full spectrum of associations in a resident's sphere of interaction were surveyed (ie, supervisors, peers, direct reports, nurses, and administrative personnel). Each resident received a comprehensive report that included detailed documentation of the self-evaluation and the average rating of others by category. Each resident also received a transcript of the responses to the open-ended questions and summary of the data highlighting areas of excellence, areas for improvement, and suggested goals and recommendations. The program director received copies of all of these as well as a chart documenting the average scores on each item for the whole cohort. RESULTS: Each resident met with the 360-degree feedback specialist and the program director to develop and commit to an action plan based on the feedback. The feedback process was repeated approximately 8 months later. CONCLUSIONS: The 360-degree feedback results provided valuable information for the residents. It also provided our program with a reproducible, quantifiable tool to assess these competencies. Combined with other instruments, the 360-degree feedback was found to be a particularly valuable instrument.

Accreditation↗

PubMed2004

Plasmolemmal potassium gradient does not affect lung protection by an ATP-regulated potassium channel opener.

BACKGROUND: We have previously shown that metabolic arrest induced with ATP-regulated potassium channel openers (PCOs) can improve lung preservation by adding Aprikalim (a PCO, Rhone-Poulene Roher) to modified Euro-Collins solution for pulmonary artery flush. Because the membrane hyperpolarizing effects of a PCO potentially competes with the depolarizing effects of a hyperkalemic solution, this study evaluated the effects of the potassium gradient on PCO-mediated lung protection. STUDY DESIGN: Twenty rabbits underwent lung protection in four groups. Group 1 underwent harvest and reperfusion as a "no ischemia" control. Groups 2, 3, and 4 underwent harvest followed by 18 hours of cold ischemic storage before reperfusion. Groups 1 and 4 received Euro Collins as the pulmonary flush at induction of ischemia. Group 2 received Euro Collins plus Aprikalim (100 microM); and group 3 received lactated Ringer's plus Aprikalim. After ischemic storage, the lungs were reperfused with autologous blood for 2 hours. Every 30 minutes, the lungs were given a 10-minute 100% fractional inspired oxygen (F(i)O(2)) challenge to measure maximal gas exchange as an indication of graft function. RESULTS: Repeated measures ANOVA showed Aprikalim improved graft function after 18 hours of cold ischemia (p < 0.0001). No significant differences were found when Aprikalim was used in either Euro-Collins (group 2) or lactated Ringer's (group 3) solution. CONCLUSIONS: The ability of the PCO Aprikalim to preserve gas exchange in a model of hypothermic pulmonary ischemia-reperfusion injury was not affected by the plasmolemmal potassium gradient. This is consistent with recent findings in myocardial protection studies that the protective effects of PCOs may be intracellular.

Adenosine Triphosphate↗

PubMed2004

Performance improvement with a multidisciplinary clinical guideline for patients undergoing minimally invasive thoracic surgery.

BACKGROUND: A horizontally integrated multidisciplinary clinical guideline was created and implemented in 1999-2000 for minimally invasive thoracic surgery (MIS). Guideline elements included complete appropriate preoperative evaluation, minimally invasive surgery techniques, aggressive anesthetic management and absolute pain control, immediate extubation, abolition of "routine" laboratory and imaging investigations, and early and aggressive postoperative patient mobilization in an integrated, multidisciplinary postthoracotomy rehabilitation program. METHODS: In a retrospective controlled cohort study, data were collected for the 501 procedures performed on 311 patients (MIS group) from July 1, 2000, to June 30, 2001, and for 130 similar procedures performed on 90 similar patients under a standard general thoracic surgery ad hoc clinical program from July 1, 1998, to June 30, 1999. RESULTS: After implementation of the clinical guideline, services expanded with a 345% increase in case volume, a 40% reduction in cost, no adverse effects, and increased referring-physician and patient satisfaction. DISCUSSION: Significant performance improvement was realized by implementing a multidisciplinary clinical guideline for thoracic surgery that seamlessly integrated all facets of diagnosis, therapy, and rehabilitation.

Cohort Studies↗

PubMed2003

Warm ischemia lung protection with pinacidil: an ATP regulated potassium channel opener.

BACKGROUND: Ischemia/reperfusion injury remains a limiting factor in lung transplantation. Traditional hyperkalemic preservation solutions are associated with a host of metabolic derangements. ATP-regulated potassium channel openers (PCOs) may provide an attractive alternative to traditional solutions by utilizing inherent mechanisms of ischemic preconditioning. The purpose of this study was to assess warm ischemia graft protection with pinacidil, a nonspecific PCO. METHODS: An isolated recirculating blood perfused ventilated rabbit lung model was used (n = 15). No ischemia control lungs underwent immediate reperfusion (n = 5). Warm ischemia control lungs were flushed with lactated Ringers (LR), stored at 37 degrees C for 2.5 hours and then reperfused for 2 hours (n = 5). PCO protected lungs were flushed with LR + 100 micromol/L pinacidil, stored, and then reperfused (n = 5). Intermittent blood gases were taken from the pulmonary artery and left atria. Every 30 minutes, graft function was assessed with a 10-minute 100% fractional inspired oxygen concentration challenge to measure maximal gas exchange. Lung samples were graded for histologic injury and assayed for myeloperoxidase activity. RESULTS: A mixed-models repeated measures ANOVA demonstrated a significant difference between groups. Tukey's honestly significant difference multiple comparison test demonstrated significantly improved graft function and reduced histologic injury with pinacidil protection compared with the warm ischemia controls. There was no significant difference in graft function or pathology grade between the pinacidil protected lungs and the no ischemia controls. A similar trend, although not significant, was seen in myeloperoxdiase activity. CONCLUSIONS: Potassium channel openers with pinacidil can provide pulmonary protection against warm ischemia reperfusion injury.

Animals↗