The presence of the glucocorticoid (GC) receptor is required for GC-evoked apoptosis. However, the explicit mechanism of involvement of this receptor continues to be debated. Employing the murine (S-49) and human (CCRF-CEM) lymphoid cell lines, we demonstrated that this response requires a specialized form of the glucocorticoid receptor (GR) that resides in the plasma membrane (mGR). Our studies of mGR have been done in our stable mGR-enriched (by sequential cell separation--immunopanning, fluorescent cell sorting, soft agar cloning) S-49 and CCRF-CEM cells. Direct and indirect immunofluorescent studies of live intact cells showed GR-specific periplasma membrane staining. Immunoanalysis by flow cytometry demonstrated abundant mGR in mGR++ cells, but only barely detectable mGR in mGR-- cells. Western blot and autoradiographic analyses of immunoprecipitated membrane extracts from these cells show they contain immunoreactive and competitively labeled high Mr receptor ranging from 94 to 150 kDa. Using mGR++ CCRF-CEM cells and three synchronization procedures (double thymidine, thymidine/colcemid, and colcemid blocks), we have investigated the influence of cell cycle on regulation and function of mGR. Both mGR expression and GC-mediated lymphocytolysis appear highest at late S-G2/M. Analysis of mGR in lymphocytes of several leukemic patients indicated differences in the levels of receptor expression. These findings might provide diagnostic clues about patients' differential response to steroid therapy and potential therapeutic avenues for effective treatment of hormone-responsive leukemic patients.

Animals↗

PubMedDate not supplied

Engineering dental pulp-like tissue in vitro.

Injury or infection of adult dental pulp often necessitates root canal therapy. This terminates dentin formation and subsequent tooth maturation. In addition, the synthetic materials currently utilized to replace lost tooth structure are not capable of completely replacing the function of the lost tissue, and often fail over time. This report describes a technique to engineer new pulp-like tissues utilizing cultured cells and synthetic extracellular matrices. Fibroblasts were obtained from human adult dental pulps and multiplied in culture. These cells were subsequently seeded onto synthetic matrices fabricated from fibers (approximately 15 microns in diameter) of polyglycolic acid (PGA). The pulp-derived fibroblasts adhered to the fibers, proliferated, and formed a new tissue over 60 days in culture with a cellularity similar to that of native pulp. These tissues may find application in the regeneration of oral tissues and may provide novel systems in which to study the biocompatibility of materials and chemicals used in dentistry.

Adult↗

PubMedDate not supplied

Snapshot of acute asthma: treatment and outcome of patients with acute asthma treated in Australian emergency departments.

AIMS: To characterize presentations due to acute asthma at Australian emergency departments (ED), including their severity, treatment and disposition. METHODS: This prospective, observational study involved 38 departments of emergency medicine throughout -Australia participating in the Snapshot of Asthma Study Group project 2000 and 2001. Data were collected for patients presenting with acute asthma between 21 August 2000 and 3 September 2000, and 20 August 2001 and 2 September 2001 and included demographics, severity classification, treatment and disposition. RESULTS: There were 1340 acute asthma presentations in the study periods. Of these presentations, 67% were for children aged <15 years. Asthma severity (according to the Australian National Asthma Guidelines classification) was 'mild' in 49% of cases; 'moderate' in 45% of cases; and 'severe' in 6% of cases. Treatment administered included: (i) salbutamol to 90%, (ii) ipratropium bromide to 59% and (iii) corticosteroids to 71%. Only six patients received aminophylline. Spacer use for salbutamol was rare (1%) in adults and only moderate (43%) in children. Sixty-five percent of patients were discharged home from the ED. Less than 1% of patients required ventilatory assistance, of which half was provided non-invasively. One percent of patients were admitted to the intensive-care unit or high-dependency unit. CONCLUSION: Overall adherence to treatment guidelines was good. There appears to be underuse of spacers and corticosteroids in some groups and overuse of ipratropium bromide. The majority of patients are treated and discharged from the ED.

Adolescent↗

PubMedDate not supplied

Evaluation of Opsite catheter dressings for parenteral nutrition: a prospective, randomized study.

A prospective, randomized study compared the use of Opsite and standard gauze/tape dressings in 261 patients receiving parenteral nutrition. Eighty-four patients had a source of external drainage and were evaluated as a separate group. Catheter-related sepsis was assessed by blood culture, catheter tip culture, clinical sepsis, and clinical defervescence of fever after catheter removal. Although no statistically significant difference between Opsite and standard dressings could be identified, Opsite-treated patients consistently had increased parameters of catheter-related sepsis in all comparisons. As used here, Opsite is probably not a suitable catheter dressing system for parenteral nutrition.

Bandages↗