Cytochrome P450 1B1 expression in rat esophageal tumorigenesis promoted by gastric and duodenal reflux.

Cytochrome P450 1B1 (CYP1B1) mRNA is constitutively expressed in most normal extra-hepatic tissues; however the protein is not detectable in these tissues but is expressed in a wide variety of tumors. CYP1B1 is responsible for the activation of a number of carcinogens present in tobacco smoke and food. A surgical model of rat esophageal tumorigenesis, promoted by gastric or duodenal reflux was used to determine CYP1B1 expression in premalignant esophageal tissue. Immunohistochemistry was performed using a modified amplified fluorescein tyramide protocol. CYP1B1 was not observed in normal esophageal mucosa, submucosa, or muscularis mucosa. Animals exposed to gastric reflux developed mild hyperplasia. Varying degrees of hyperplasia were observed in the duodenal reflux group. All regions of hyperplasia showed moderate or strong CYP1B1 immunoreactivity. Duodenal reflux induced a small number of premalignant changes: immunoreactivity was absent from the epithelium of squamous dysplasia (0/10), Barrett's esophagus (0/7), and majority of dysplastic Barrett's esophagus (1/4). Moderate or strong immunoreactivity was observed in the majority (7/8) of squamous cell carcinomas (SCCs) in situ. Immunoreactivity was also observed in the lamina propria and submucosa in association with inflammation, regardless of the severity of inflammation. The expression of CYP1B1 in hyperplasia, SCCs in situ, or in association with inflammation may increase the production of carcinogenic metabolites, which may promote esophageal tumorigenesis.

An Examination of the Use of Coercion by Assertive Outreach and Community Mental Health Teams in Northern Ireland.

In mental health services over recent decades, the positive move away from hospital-based care to community-based services has entailed that people with higher levels of need are being supported by community mental health services. This paper begins by reviewing the literature on coercion in the field of community-based mental health care and treatment. It is argued that the lack of a critical understanding of the concept and how it is used by practitioners and agencies can have serious repercussions for the rights of service users. Using a quasi-experimental, longitudinal design, the authors then seek to test some of the ideas about coercion by comparing the activities of assertive outreach and community mental health teams in Northern Ireland, particularly the key ideas of perceived coercion, workers’ strategies and engagement with services. Key findings were that assertive outreach appeared to be more successful at reducing perceived coercion, minimizing the need for coercive strategies, engaging high-risk clients and reducing inpatient bed use. These findings are compared with other studies in this area. The authors also argue that there is a need for greater transparency in the way that practitioners use coercive measures and more explicit guidance is required in this crucial area of mental health practice.