Activation of endothelial cell phospholipase D by migrating neutrophils.

Background: Vascular endothelium plays a critical role in regulating the integrity of intercellular adhesive and junctional contacts in response to migrating neutrophils during the inflammatory process. Biochemical responses induced in endothelial cells by adherent, migrating neutrophils are poorly understood. This study was undertaken to explore the possibility that endothelial cell phospholipase D (PLD) is activated when neutrophils migrate through endothelial cell monolayers in response to chemotactic stimuli.

The determination of membrane permeability coefficients of canine pancreatic islet cells and their application to islet cryopreservation.

Sufficient numbers of pancreatic islets for successful allotransplantation can be achieved by storing and then pooling islets from several donors. Optimal MHC matching and infectious disease screening also require long-term storage of islets, and cryopreservation is currently the only practical approach. Cryopreservation protocols may be optimized by modeling the changes in cell volume and the associated damage incurred during cryoprotectant addition and dilution and during cooling and warming.

Allogeneic and xenogeneic transplantation of cryopreserved ovarian tissue to athymic mice.

Cryopreserved ovarian tissue has major applications for female oncology patients and for the development of genome resource banks. The objective of the present study was to develop a bioassay of cryopreserved ovarian tissue function after allogeneic and xenogeneic transplantation to ovariectomized athymic nude (nu/nu) Balb/C mice. Transplant function was assessed by examination of vaginal smears, number of live births, and posttransplant histology.

Hypoosmotic exposure of canine pancreatic digest as a means to purify islet tissue.

The development of more effective means to separate pancreatic islets from the unwanted exocrine tissue would greatly advance the field of clinical islet allotransplantation in the treatment of insulin-dependent diabetes mellitus. Recent experiments with hamster islets have demonstrated a selective destruction of dissociated single exocrine cells when exposed to hypotonic conditions. It was the aim of this study to extend these observations to the canine model with collagenase dissociated pancreatic tissue and to evaluate the treatment's effect on islet function.

Characterization and purification of neutrophil ecto-phosphatidic acid phosphohydrolase.

Phosphatidic acid and its derivatives play potentially important roles as extracellular messengers in biological systems. An ecto-phosphatidic acid phosphohydrolase (ecto-PAPase) has been identified which effectively regulates neutrophil responses to exogenous phosphatidic acid by converting the substrate to diacylglycerol. The present study was undertaken to characterize this ecto-enzyme on intact cells and to isolate the enzyme from solubilized neutrophil extracts.

Lineage commitment of HLA-DR/CD38-defined progenitor cell subpopulations in bone marrow and mobilized peripheral blood assessed by four-color immunofluorescence.

We used four-color fluorescence analysis to compare lineage antigen expression in relationship to CD38 and HLA-DR on CD34+ progenitor cells in adult human bone marrow and mobilized peripheral blood. Each of four progenitor cell subpopulations defined by HLA-DR and CD38 intensity (CD38-/HLA-DR-, CD38-/HLA-DR+, CD38+/HLA-DR+, and CD38+/HLA-DR-) were present in both progenitor cell sources in similar ratios. The most prevalent subpopulation consisted of cells that expressed both CD38 and HLA-DR.

Counterflow centrifugal elutriation as a method of T cell depletion may cause loss of immature CD34+ cells.

Counterflow centrifugal elutriation (CCE) is capable of separating cells on the basis of size. CCE has been used successfully to deplete allogeneic bone marrow (BM) grafts of T lymphocytes to decrease the risk of acute graft-versus-host disease. Previous studies have shown that more immature CD34+ cells in human BM tend to be smaller than more mature CD34+ cells.

Radiographic detection of gravel in soft tissue.

Study Objective: We sought to quantify the detectable size of varying compositions of gravel using a cadaveric chicken leg wound model and standard plain-film two-view radiographs.

Methods: We conducted a randomized, blinded, descriptive study with the assistance of faculty from the emergency medicine and radiology residency programs of a private urban teaching hospital. A standardized wound was created in each of 160 cadaver chicken legs.

Phosphatidic acid-mediated regulation of neutrophil plasma membrane CD45-phosphotyrosine phosphatase.

CD45-phosphotyrosine phosphatase (PTPase) constitutes the major portion of thr PTPase activity within plasma membranes of neutrophilic leukocytes, where it regulates signals leading to functional activation. We have previously demonstrated that the catalytic component of neutrophil plasma membrane CD45-PTPASE is regulated by a cytosolic inactivator which itself is attenuated upon cellular stimulation, allowing enzyme translocated from granule stores to express full activity. The present study investigated mechanisms of cytosolic inactivator attenuation.

Pearls, pitfalls, and updates for pain management.

Pain management is one of the most challenging areas we encounter as emergency physicians. However, many of us fail to adequately meet this challenge. This article discusses frequently encountered pain syndromes and pain management options.

Cardiology.

Emergency cardiac problems are a frequent and significant occurrence in the daily life of the emergency physician. The first part of this article discusses some of the pearls and pitfalls of caring for the cardiac patient ranging from treating wide-complex tachycardia and troubleshooting pacemaker malfunction to diagnosing acute myocardial infarction in the setting of bundle branch blocks. The second part of this article updates the reader on several of the newer technologies and treatments, such as transesophageal echocardiography and intravenous amiodarone, now in use in the emergency department setting.

Differences in CD34+ cell subpopulations between human bone marrow and "mobilized" peripheral blood as determined with counterflow centrifugal elutriation.

Engineering of hematopoietic progenitor cells (HPCs) from bone marrow (BM) or "mobilized" peripheral blood (MoPB) is becoming increasingly important. Counterflow centrifugal elutriation (CCE) has been used to separate cells on the basis of their size. In this study, CCE was applied to evaluate BM and MoPB for differences in their HPC populations.

Hodgkin's disease variant of Richter's syndrome. Report of a case with diagnosis by fine needle biopsy.

Background: Chronic lymphocytic leukemia (CLL) with transformation into large cell lymphoma (Richter's syndrome) is a well-documented phenomenon. Only rarely does CLL terminate in Hodgkin's disease (HD) as Richter's syndrome. Reports of Hodgkin's variant of Richter's syndrome proven by histologic and immunohistologic evaluation have been published, but no cytologic reports of this entity exist.

Is closed diagnostic peritoneal lavage contraindicated in patients with previous abdominal surgery?

Objective: To compare the accuracies and complication rates of diagnostic peritoneal lavage (DPL) in trauma patients with and without previous abdominal surgery.

Methods: A retrospective review of DPL accuracy and complication rate was performed using all ED trauma patients who underwent DPL during 1993 as identified by the trauma registry. Care was provided at a Level-1 trauma center, a 1,100-bed, central-city teaching hospital with an annual ED census of 84,000.

Composite chondrocutaneous advancement flap: a technique for the reconstruction of marginal defects of the ear.

A composite chondrocutaneous advancement flap is described for the reconstruction of full thickness marginal defects of the ear. It has been used successfully in two patients to reconstruct defects involving the helix and scapha and is recommended for defects whose wound dimensions exceed the limitations of both wedge excision and Antia and Buch's chondrocutaneous flap.

Small bowel cancer. Radiologic diagnosis.

The diagnosis of small bowel cancer before it has metastasized continues to be a clinical and radiologic dilemma. This article presents an overview of the role of radiology in the diagnosis of small bowel cancer, describes techniques for optimal radiologic examination, and presents a pictorial essay of the radiologic features and differential diagnoses of these tumors.

Analyses of HLA-DQ alleles in recurrent spontaneous abortion (RSA) couples.

Problem: The influence of HLA sharing on pregnancy outcome is controversial. In renal transplantation, HLA-DQB1 donor-recipient mismatches have been shown beneficial for long-term transplant success. Since pregnancy is defined as Nature's allograft, we investigated the relevance of HLA-DQ mismatching in normal reproducing couples compared to couples experiencing RSA.

Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa.

The objective was to test the hypothesis that the optimal cryoprotective agent for cryopreservation of human spermatozoa would be a solute for which cells have the highest plasma membrane permeability, resulting in the least amount of volume excursion during its addition and removal. To test this hypothesis, theoretical simulations were performed using membrane permeability coefficients to predict optimal procedures for the addition and removal of a cryoprotectant. Simulations were performed using data from four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide, (iii) propylene glycol and (iv) ethylene glycol.

Live births after autologous transplant of cryopreserved mouse ovaries.

The fertility of mice after autologous transplantation of ovaries, before or after cryopreservation, was investigated in this study. Female mice were randomly assigned to either sham-operated (n = 14), ovariectomized (n = 11), fresh (n = 12) or cryopreserved (n = 11) ovarian transplant groups. Ovaries were cryopreserved in 1.

Treatment of nonmetastatic osteosarcoma of the extremity with preoperative and postoperative chemotherapy: a report from the Children's Cancer Group.

Purpose: The specific aims of this study were to improve event-free survival (EFS) in patients with newly diagnosed nonmetastatic osteosarcoma of an extremity using the histologic response to neoadjuvant chemotherapy to determine postoperative chemotherapy; to evaluate a uniform histologic grading system that measures tumor response; and to identify patient characteristics that might influence EFS and survival.

Patients And Methods: Two hundred sixty-eight patients with nonmetastatic osteosarcoma of the extremity were entered between August 1983 and October 1986. Preoperative chemotherapy consisted of four courses of high-dose methotrexate (MTX) and one course of bleomycin, cyclophosphamide, and dactinomycin (BCD).

Factors associated with nursing interventions to reduce incontinence in hospitalized older adults.

Introduction: The problem of incontinence in hospitalized elderly patients is rarely documented, and there is little research that determines why nurses choose to help or not help with this problem. Are hospital-based acute care nurses' attitudes and beliefs about incontinence associated with the perceived opportunity to assist the patient with the problem? What do hospital nurses know about causes and interventions relative to incontinence?

Methods: Two vignettes, one describing a patient with stress incontinence and one describing a patient with urge incontinence, were created. Questions measuring variables of a help-giving model were developed, and nurses were asked to mark on a Likert-type scale when answering each question.