Search PubMed⌕ Search

Biomedical subjects

T K Smith

Publications and source records attributed to T K Smith.

185 records · Page 11Linked to original sources

Individual Assessment Profile (IAP). Standardizing the assessment of substance abusers.

The Individual Assessment Profile (IAP), a structured intake assessment interview instrument in the public domain, was designed for use with substance-abusing populations in several large-scale and community-based drug abuse treatment projects underway in the United States. Background information is presented, including the content-based item-selection process used during the pretests and pilot testing. Validity and test-retest reliability data are also presented, along with descriptions of studies using the IAP for clinical, research, and management information purposes. Concordance between biological measures and self-reports of recent drug use, measures of internal consistency, and test-retest reliability coefficients were generally good. A computer-assisted personal interview version of the IAP and an automated reporting system were subsequently developed for clinical and management reporting purposes and used in a large-scale research demonstration project. An intreatment version of the IAP has also been developed to collect information on treatment services provided and to assess changes in behaviors after 3, 6, and 12 months of treatment. These instruments (the IAP intake and intreatment interviews) provide a comprehensive system to assess substance-abusing populations.

Adolescent↗

Clonogenic assay combined with flow cytometric cell sorting for cell-cycle analysis of human leukemic colony-forming cells.

The purpose of this study is to develop a method combining clonogenic assay and flow cytometric cell sorting based on DNA content for determination of percentage distribution of human malignant clonogenic cells over cell-cycle phases. Flow cytometric cell sorting was carried out for Chinese Hamster Ovary (CHO) and human leukemic bone marrow cells under sterile conditions using a supravital dye for DNA, 4',6-Diamidino-2-phenylindole dihydrochloride (DAPI). The fraction sorted for G0/G1 CHO cells was verified to be almost completely free of G2/M cells and partially cleared of S-phase cells. Cells sorted for G0/G1 fraction were successfully grown as colonies in culture for both CHO and human leukemic marrow cells. The plating efficiency of sorted cells was lower than that of unsorted cells, and the relative contribution of cell damage versus cell selection cannot be determined for this reduction of plating efficiency. The purity of sorted cells must still be improved, and the reason for reduced plating efficiency remains to be defined by further studies. Nonetheless this report represents initial data demonstrating the feasibility of combining two technologies: clonogenic assay and flow cytometric cell sorting based on DNA content. As such, it paves the way for a new approach to studying the cell cycle kinetics of clonogenic cell subpopulations of malignant tissues freshly obtained from patients.

Animals↗

Comparison of interlaboratory variation in amino acid analysis and rat growth assays for evaluating protein quality.

Estimates of inter- and intralaboratory variation of protein efficiency ratio (PER), relative PER (RPER), net protein ratio (NPR), relative NPR (RNPR), and nitrogen utilization (NU) were compared with those of amino acid analysis in the same batches of 7 protein sources (ANRC casein, egg white solids, minced beef, soy assay protein, rapeseed protein concentrate, pea flour, and whole wheat flour). Interlaboratory variation (estimated as between-laboratories coefficients of variation, CV) of NPR and RNPR (up to 6.0%) was lower than that of PER (up to 20.2%) and RPER (up to 18.5%). The interlaboratory determination of NPR and RNPR was also more reproducible than that of most essential amino acids (CV up to 10.0%), especially tryptophan (CV up to 23.7%), cystine (CV up to 17.6%), and methionine (CV up to 16.1%). Intralaboratory variation (estimated as within-laboratories CV) of amino acid analysis (up to 4.7%), however, was comparable to that of protein quality indices in most protein sources (up to 6.0%). The significant (P less than 0.01) positive correlations (r = 0.68-0.74) between amino acid scores and protein quality indices based on rat growth were further improved when amino acid scores were corrected for digestibility of protein (r = 0.73-0.78) or individual amino acids (r = 0.79-0.82).

Amino Acids↗

Inter- and intra-laboratory variability in rat growth assays for estimating protein quality of foods.

Protein efficiency ratio (PER), relative PER (RPER), net protein ratio (NPR), relative NPR (RNPR), and nitrogen utilization (NU) methods were investigated in an interlaboratory rat growth study. Six collaborating laboratories studied 7 protein sources (ANRC casein; minced beef; soya assay protein, SAP; pea flour; whole wheat flour, WW; rapeseed protein concentrate, RPC; and egg white solids, EW), and their 10 supplementary or complementary mixtures (casein + Met, SAP + Met, pea flour + Met, WW + Lys, WW + casein, WW + beef, WW + SAP, WW + pea flour, WW + RPC, WW + EW). Test protein(s) were added at the 8% level (N X 6.25). Casein + Met was used as the reference protein. Interlaboratory variation (estimated as between-laboratories coefficients of variation) of PER (up to 17.2%) was greater than that of RPER (up to 14.9%), NU (up to 9.5%), NPR (up to 7.0%), and RNPR, which had the lowest variability (up to 4.7%). In most cases, intralaboratory variation (estimated as within-laboratories coefficients of variation) for all the methods was less than 5%.

Animals↗