Clozapine: more than 900 mg/day may be needed.

Patients may fail to respond to clozapine treatment despite use of the maximum licensed UK dosage (900 mg/day) because of ultra-rapid metabolism of the drug. We present the findings of a study of a national clozapine/norclozapine assay service for the period 1997-2005 and three individual case studies of patients treated with clozapine in doses greater than 900 mg/day. Clinicians should be alert to the possibility of treatment failure because of rapid clozapine clearance secondary to genetic factors and heavy cigarette consumption.

A staff perspective of early warning signs intervention for individuals with psychosis: clinical and service implications.

Research has established the benefits of early warnings signs monitoring in the prevention of relapse for individuals with psychosis. This study explored staff views (n = 8) of the implementation of an early warning signs clinic within a day hospital of an adult mental health service. A qualitative methodology using focus groups was adopted and content analysis was used to discover themes arising from the data.

Morphology and chemistry of brown rat,Rattus norvegicus, preputial and clitoral glands.

In contrast to previous results from laboratory rats, when sexual dimorphism occurred, clitoral glands from wild female rats were heavier and accounted for a greater proportion of body mass than preputial glands from wild males. Gland length and weight increased with body weight, but gland weight as a proportion of body weight did not. Preputial and clitoral glands showed seasonal differences in size: at one site glands were smaller in December than in April.

Analysis of rat haunch odor using dynamic solvent effect and principal component analysis.

We used the dynamic solvent effect to sample rat haunch odor, which we then analyzed using principal component analysis. PCA, based on 22 volatile components, indicated that one axis clearly separated rat haunch odor samples according to sex and female reproductive condition (estrus and diestrus), explaining 79.5% of the variation in proportional peak area.

Scent, sex, and the self-calibrating rat.

We propose that one mechanism whereby male rats,Rattus norvegicus, might gauge the reproductive condition of a female is by calibrating a stable odor with an odor that fluctuates through her reproductive cycle. We provide behavioral and histological evidence in support of such a self-calibration model. Male rats sniffed frequently at various body zones of females, and the proportion of sniffs deployed to each zone varied with the females' reproductive condition and relatedness.