PubMed Health⌕ Search

Biomedical subjects

Bruce Pollock

Publications and source records attributed to Bruce Pollock.

5 recordsLinked to original sources

Determination of ziprasidone in human plasma by liquid chromatography-electrospray tandem mass spectrometry and its application to plasma level determination in schizophrenia patients.

An accurate, rapid and simple liquid chromatography-tandem mass spectrometry (LC-MS-MS) assay method was developed for the determination of ziprasidone (ZIP) in the plasma of schizophrenia patients. A simple one step liquid-liquid extraction with 20% methylene dichloride in pentane was used to isolate ZIP and the internal standard from the plasma matrix. The compounds were separated on a C-18 column by an isocratic elution and the eluted compounds were analyzed by a triple quadrupole mass spectrometer with a TurboIon spray interface using the positive ion atmospheric pressure electrospray ionization method and detected using multiple reaction monitoring mode. The ZIP standard calibration curve was linear over the range of 0.25-500ng/ml when 0.5ml of plasma was used for the analysis (r(2)>0.998). The intra-assay (within-day) and inter-assay (between-day) variations were less than 12% for the spiked standard curve and quality control samples. The absolute extraction efficiency was 82% for ZIP and 68% for INS-RSP. The analysis time for each sample was less than 3min and useful for high turnaround plasma level determinations. This LC-MS-MS assay method for ZIP is highly specific, sensitive, accurate and rapid and is currently being used for the plasma level determination of ZIP in schizophrenia patients treated with various daily oral doses of ZIP. The data showed large inter-individual variations.

Adult↗

Body pain and treatment response in late-life depression.

OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression.

Activities of Daily Living↗