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J Heggie

Publications and source records attributed to J Heggie.

8 recordsLinked to original sources

A psychometric evaluation of the BDI-II in treatment-seeking substance abusers.

The Beck Depression Inventory-II (BDI-II) was administered to 416 consecutive male admissions to a 28-day residential chemical dependence treatment program as part of a routine intake procedure. Psychometric analyses revealed that the BDI-II scores were internally consistent in this treatment-seeking population based on coefficient alpha. The mean BDI-II score for patients in this study was higher than that noted for other clinical samples in previous studies. The use of the BDI-II for clinical decision making with chemically dependent individuals is discussed in light of this elevated distribution of scores. Confirmatory factor-analytic examinations of the instrument revealed that a three-factor model, with cognitive, affective, and somatic symptoms loading as separate factors, provided the most adequate account of the data. In total, the study supported the use of the BDI-II for the assessment of depression in chemically dependent male patients entering a residential treatment program at a VAMC facility, provided population-specific normative data is utilized for making clinical decisions.

Depressive Disorder↗

Pharmacokinetic behavior of vincristine sulfate following administration of vincristine sulfate liposome injection.

The pharmacokinetic behavior of vincristine sulfate (VINC) following administration of vincristine sulfate liposome injection (VSLI), 0.16 mg/ml, as an intravenous infusion over 60 min in 24 of 25 patients enrolled in a phase I clinical study of this drug is described. Plasma samples for determination of the pharmacokinetic behavior of VINC were collected during the infusion at 15, 30 and 60 min as well as at 2, 4, 8, 12, 48 and 72 h postinfusion. Total VINC concentration was determined using a validated high-performance liquid chromatographic (HPLC) assay. Patients receiving doses of 0.5 to 1.5 mg/m2 VSLI did not provide useful pharmacokinetic data at late time-points owing to the limit of quantitation of the HPLC assay (28.6 ng/ml). Sufficient concentration-time data were available for seven of the patients receiving doses of VSLI from 2.0 to 2.8 mg/m2 for compartmental modelling. A two-compartment open model (PCNONLIN Model 10) was the best fit for the observed VINC plasma data for these patients. The mean maximum observed concentration values were significantly greater for patients receiving VSLI at 2.8 mg/m2 (2260 +/- 212 ng/ml, n = 2) than for those receiving 2.0 mg/m2 and 2.4 mg/m2 (891 +/- 671 ng/ml, n = 6; 679 +/- 634 ng/ml, n = 6, respectively). No significant differences were observed in maximum concentration values between patients at 2.0 mg/m2 and those at 2.4 mg/m2. A trend towards higher parametric AUC (0 to infinity) values with increasing dose (on a milligram per meter squared basis) was observed but statistical significance was not reached. Comparison of the pharmacokinetic behavior of VSLI observed in this study with nonencapsulated VINC demonstrated that (1) the variability observed for VSLI pharmacokinetic parameters was similar to nonencapsulated VINC, (2) although variability in absolute concentration was observed between patients, the behavior of VSLI in individual patients followed a two- rather than a three-compartment open model, and (3) VINC plasma concentrations were significantly greater following administration of VSLI than described for nonencapsulated VINC. Overall, the results for patients treated with VSLI from 2.0 to 2.8 mg/m2 suggest that this formulation protects VINC from the early phase of rapid elimination seen with nonencapsulated drug, resulting in significantly elevated VINC plasma concentrations over extended periods of time.

Adult↗

Measurement of the density of human platelets and its relationship to volume.

New methods are described for platelet isolation and buoyant density determination using low-speed centrifugation in continuous density gradients of Percoll. The conditions used do not induce loss of granule or cytoplasmic markers and enable reproducible platelet frequency distributions to be obtained in linear density gradients. Such frequency distributions are normal with a mode of 1.0645 +/- 0.0015 g cm-3 (mean +/- SD, n=20). Platelets fixed in 0.1% glutaraldehyde show a modal density of 1.0712 +/- 0.0005 g cm-3. Content of protein, lactate dehydrogenase, beta-thromboglobulin and 3H-serotonin correlate closely with platelet numbers throughout the density distribution. The frequency distribution of platelet volume between 2.2 and 21 fl fits a log normal model and cell volume in density subfractions from the most dense to the least dense also approximate log normality. There is a positive correlation between mean platelet volume and buoyant density with a small increment between the least and the most dense extremes. Platelet subfractions separated by volume using a FACS II cell sorter differ substantially from each other in cell volume but the difference in mean density of four different volume fractions in negligible. In discontinuous density gradients of Stractan factors other than platelet density must influence the separation of platelets, as rebanding of platelets from interfaces shows a wide variation in buoyant density when analysed in continuous gradients. It is concluded that analysis of platelet buoyant density in continuous Percoll gradients supports the view that platelet density, like platelet volume, is determined primarily during thrombocytopoiesis and that volume and density are largely independent elements of platelet heterogeneity.

Adult↗