Reduction of fear-related dental management problems with use of filmed modeling.

In this study of the modification of anxiety-related disruptive behavior in dental treatment, matched groups of inner-city children attending a pedodontic clinic were shown a videotaped demonstration of a 4-year-old black child undergoing a dental restorative procedure or were given an unrelated drawing task before dental treatment. Children who viewed the videotape demonstration of a peer model coping with dental procedures showed significantly fewer fear-related disruptive behaviors during restoration of lesions. Observations of children's anxiety levels made by dentists and independent observers validated the effectiveness of viewing the videotaped demonstration. No significant correlation was found between the children's reports of their anxiety and their behavior during dental treatment.     

Subareolar and peritumoral injection identify similar sentinel nodes for breast cancer

Background Sentinel lymph node (SLN) mapping with radioisotope and blue dye is rapidly becoming the standard of care for breast cancer. The optimal location for injection of radioisotope and blue dye is still being investigated. The goal of this study was to determine whether blue dye injection into the subareolar (SA) location localized the same sentinel nodes as the peritumoral (PT) location for patients with breast cancer. Methods Three hundred thirty-two patients with biopsy-proven operable breast cancer or ductal carcinoma in situ at two institutions underwent SLN mapping. Eighty-three patients had PT injection of blue dye (group 1), and 249 patients had SA injection of blue dye (group 2). All patients underwent PT injection of^99mTc-labeled sulfur colloid. Results The two groups were similar in age, previous biopsy type, and tumor size, location, and histology. The mean number of SLNs identified was 2.4 (range, 0–9) in group 1 and 2.5 (range, 0–11) in group 2. The SLN identification rate was 95% for group 1 and 97% for group 2. The isotope success rate was 94% for both groups. The blue dye success rate was 84% for group 1 and 90% for group 2. The isotope/blue dye concordance rate was 87% for group 1 and 90% for group 2. At a median follow-up of 28 months (range, 14 to 40), there were no axillary recurrences in any of the 332 patients. Conclusions These data suggest that delivery of mapping reagents in the SA and PT locations identifies similar lymph nodes. Because of simplicity and the similarity in node identification between SA and PT injection, further investigation of the SA site for delivery of SLN mapping reagents for breast cancer is warranted. Presented at the 54th Annual Cancer Symposium, Society of Surgical Oncology. Washington, DC, March 15–18, 2001.     

Ethical Considerations in Air Pollution Research

The acceleration of tumor production in mice by repeated application of polycyclic aromatic hydrocarbon carcinogens of high and low potency in the presence of cocarcinogenic compounds is described. Experiments exploring the concentration levels of carcinogen and cocarcinogen necessary to produce tumors demonstrate that there is a 1,000-fold increase in the enhancement of potency of low concentrations of benzo[a]pyrene and benz[a]anthracene when n-dodecane is the diluent. The effect of cocarcinogens is most obvious during exposure to low concentrations of carcinogen. The implications of this observation in the environment is discussed.     

Medullary thymic epithelial cell depletion leads to autoimmune hepatitis

TRAF6, an E3 ubiquitin protein ligase, plays a critical role in T cell tolerance by regulating medullary thymic epithelial cell (mTEC) development. mTECs regulate T cell tolerance by ectopically expressing self-antigens and eliminating autoreactive T cells in the thymus. Here we show that mice with mTEC depletion due to conditional deletion of Traf6 expression in murine thymic epithelial cells (Traf6ΔTEC mice) showed a surprisingly narrow spectrum of autoimmunity affecting the liver. The liver inflammation in Traf6ΔTEC mice exhibited all the histological and immunological characteristics of human autoimmune hepatitis (AIH). The role of T cells in AIH establishment was supported by intrahepatic T cell population changes and AIH development after transfer of liver T cells into immunodeficient mice. Despite a 50% reduction in natural Treg thymic output, peripheral tolerance in Traf6ΔTEC mice was normal, whereas compensatory T regulatory mechanisms were evident in the liver of these animals. These data indicate that mTECs exert a cell-autonomous role in central T cell tolerance and organ-specific autoimmunity, but play a redundant role in peripheral tolerance. These findings also demonstrate that Traf6ΔTEC mice are a relevant model with which to study the pathophysiology of AIH, as well as autoantigen-specific T cell responses and regulatory mechanisms underlying this disease.     

P ARAMEDIC U SE OF E NDOTRACHEAL T UBE I NTRODUCERS FOR THE D IFFICULT A IRWAY

Objective. To evaluate the ability of paramedics to learn and apply the skill of introducer-aided oral intubation in the setting of the simulated “difficult airway.” The authors hypothesized that, following a brief introduction to the device, intubation success rates would not differ for traditional and introducer-aided intubations of an immobilized airway mannequin. Methods. During a paramedic recertification class, experienced paramedics were given a brief didactic introduction to the “bougie-like” Flex Guide endotracheal tube introducer (ETTI). The participants were then asked to intubate adult mannequins immobilized in the head-neutral position, with and without the ETTI. “Successful placement” was defined as completion of the procedure within 30 seconds and endotracheal tube position confirmed by the investigator with direct visualization. Results. For both traditional and ETTI intubations, 34 (97%) of the 35 paramedics successfully intubated within 30 seconds. The two unsuccessful intubation attempts were recognized by the paramedic as esophageal intubations, and correct tube placement was obtained within an additional 30 seconds. Conclusion. In this study, use of the ETTI was mastered by the participants after only a brief didactic introduction to the device, with their ability to intubate an immobilized mannequin using the ETTI being equal to their ability to perform traditional intubation. These results suggest that use of the ETTI is easily learned, and may support the device's role in the prehospital management of the difficult airway.     

Book Received

There exist numerous difficulties in the recruitment of patients to drug trials for Alzheimer's disease. This article describes a successful community-based case-finding strategy. The success is largely attributed to effective liaison between the co-ordinating psychiatrist, GPs, community psychiatric nurses and practice nurses.