Fatal thermal injury

Two fatal cases of thermal injury are described, one of which was the result of heat stroke and the other was the result of the uncommon condition, neuroleptic malignant syndrome. The clinical profiles, management and post-mortem findings of these two separate conditions are compared to highlight their important differences.     

Chiari II malformation: MR imaging evaluation

The purpose of this study was to explore the value of high-detail MR imaging in the diagnosis of the Chiari II malformation. Twenty-four patients with known Chiari II malformation as diagnosed by CT scanning were evaluated with cranial MR scans. Two patients also had spine scans. The sagittal-plane images were the most informative, and abnormalities of the telencephalon, diencephalon, mesencephalon, rhomboencephalon, upper spinal cord, and mesencephalon were shown extremely well. We found MR to be an easy and accurate method for demonstrating the abnormalities of the Chiari II malformation, and it is our procedure of choice.     

Hepatitis A antibody in blood donors in North East Thames region: implications to prevention policies

A total of 1786 blood donors were screened for the presence of anti-hepatitis A antibody (anti HAV). 64.5% of the donors were found to be positive. The prevalence of the antibody was found to be age-related, 55% at 18 years and 75% at 65 years. No relationship was noted between the presence of antibody, foreign travel or a specific destination. Assay of antibody levels in selected seropositive individuals gave a mean level of 5.0 IU/ml. The prevalence of infection in this selected population is important in the context of passive immunization with normal human immunoglobulin and for defining a policy of immunization with hepatitis A vaccines, which are currently undergoing clinical trials.     

The differential retrocardiac air-fluid level: a sign of intrathoracic gastric volvulus

A single retrocardiac air-fluid level on a chest radiograph typically implies the presence of a sliding hiatal hernia. A differential retrocardiac fluid level (two air-fluid interfaces at different heights) suggests not a simple sliding hiatal hernia but rather an intrathoracic gastric volvulus. Simultaneous fluid levels above and below the diaphragm are not required to make the diagnosis. We have seen four patients with chronic gastric volvulus confirmed by upper gastrointestinal barium examination. Each case was diagnosable on the basis of the chest radiographs obtained on admission, using the radiographic sign described above. We draw attention to this sign because chronic gastric volvulus has the potential to progress to acute volvulus and gastric ischemia or infarction.     

Double-orifice mitral valve with intact atrioventricular septum: an echocardiographic study with anatomic and functional considerations.

We identified 18 patients with double-orifice mitral valve (DOMV) and intact atrioventricular (AV) septum out of 40,179 echocardiographic studies performed between 1997 and 2002 at Children's Hospital, Denver, CO. In this study we describe (1) the anatomic characteristics of the DOMV in the absence of AV septal defect, (2) the function of the mitral valve by spectral and color Doppler flow mapping, and (3) associated lesions. The topographic location of the orifices in the leaflets suggests possible embryologic mechanisms of DOMV. In this series, DOMV was most commonly associated with left-sided obstructive lesions (in 39% of patients). Spectral and color Doppler interrogation demonstrated a normal flow profile in most cases; only 2 patients had significant mitral regurgitation or stenosis. Therefore, due to the uncertain natural history of this lesion and the potential need for endocarditis prophylaxis, careful imaging of the mitral valve is recommended, particularly in the presence of left-sided obstructive lesions.     

Statistical Considerations in Identifying Mechanisms of Change

The statistical search for mechanisms of change involves multiple inferential tests, ones that generally follow a fixed sequence designed to demonstrate mediation. While there are several popular approaches to conducting such tests, e.g., SEM and MRA, the inflated Type I error rate problem associated with conducting these tests has received little, if any, attention. This paper offers 2 solutions to avoid committing Type I errors associated with mediational tests. Most straightforward, investigators may choose to use a Bonferroni adjustment. In contrast, a design-based approach can be used that tests rival explanations for the observed effects. Examples drawn from addiction research are provided.     

Psychological morbidity after myocardial infarction in an area of deprivation in the UK: evaluation of a self-help package.

BACKGROUND: Psychological morbidity after an acute myocardial infarction (AMI) is known to be common, but can be addressed by appropriate rehabilitation. The area in which this research was conducted experiences high rates of deprivation and of coronary heart disease and limited access to hospital-based rehabilitation. Responding to concern about psychological needs of AMI patients, a self-help package was introduced and evaluated alongside standard hospital-based cardiac rehabilitation. AIMS: To evaluate the impact of a home-based self-help package (the Heart Manual), alongside existing cardiac rehabilitation provision, on psychological morbidity and health status after AMI. A secondary aim was to assess the suitability of the Heart Manual for older patients aged over 80 years. METHODS: A controlled observational study, comparing two cohorts of patients discharged from hospital after AMI. The intervention group was given the self-help package in addition to standard care. The control group received standard care alone. Outcome measures used were the Hospital Anxiety and Depression Scale and the EuroQol. RESULTS: The intervention group showed significant improvement in anxiety and depression scores after 3 months and nonsignificant improvement in general health status. Patients who attended hospital-based rehabilitation classes, and those aged over 80 years, also benefited from the intervention. CONCLUSION: A home-based self-help rehabilitation package is an effective tool alongside hospital-based rehabilitation classes and can be given to all age groups.     

Interferon-gamma knockout fails to confer protection against obliteration in heterotopic murine tracheal allografts.

BACKGROUND: Interferon-gamma, produced by T-helper cells, activates macrophages and increases expression of major histocompatibility complex (MHC) products in acute and chronic rejection. We investigated the role of interferon-gamma in murine heterotopic tracheal allografts. METHODS: Tracheas from BALB/c mice were heterotopically transplanted to BALB/c (12 isografts: 2 weeks [n = 6] and 4 weeks [n = 6], C57BL/6 (12 allografts: 2 weeks [n = 6] and 4 weeks [n = 6]) and C57BL/6 interferon-gamma knockout mice (12 interferon-gamma knockout allografts: 2 weeks [n = 4] and 4 weeks [n = 8]). BALB/c interferon-gamma knockout tracheas were transplanted to C57BL/6 mice (reverse knockout: 4 weeks [n = 6]) and BALB/c interferon-gamma knockout mice (4 weeks [n = 2]). C57BL/6 tracheas were transplanted to Bm12 mice (MHC Class II mismatch allografts: 4 weeks [n = 6]). Conventional histology and immunohistochemistry for CD4, CD8 and CD11b were performed. RESULTS: Minimal (<20%) obliteration was seen at 2 weeks in the allograft groups. No obliteration was seen in the isograft groups. However, all allografts were completely obliterated at 4 weeks. Interferon-gamma knockout allograft combinations displayed severe rejection characterized by intense intra- and extraluminal infiltration by CD4-, CD8- and CD11b-labeled cells. The MHC Class II mismatch allograft group showed normal epithelium and mild sub-epithelial infiltration by CD4+ cells at 4 weeks (CD8-, CD11b-). CONCLUSIONS: Absence of interferon-gamma does not protect the allograft from obliteration. Epithelial destruction by cytotoxic T cells appears to be an important mechanism in the development of obliteration in murine heterotopic tracheal allografts.