Search PubMed⌕ Search

Biomedical subjects

D Hamilton

Publications and source records attributed to D Hamilton.

167 records · Page 10Linked to original sources
PubMedDate not supplied

Research implications for alternative health therapies.

Nontraditional health practices have gained in popularity during the past 10-15 years. Unfortunately, the effectiveness of many nontraditional approaches have been inadequately investigated. Furthermore, tradition research protocols often have fallen short in providing satisfactory strategies for these types of investigations because the nature of the personal belief system between patient and provider has not been examined. The authors discuss the implications for triangulation techniques in nursing research related to nontraditional treatments. Six types of triangulation are defined and methods for utilizing these techniques are explained.

Complementary Therapies↗
PubMedDate not supplied

In vitro assessment of vancomycin HCl compatibility after coinfusion with a specialized amino acid formulation.

Vancomycin usage at British Columbia's Children's Hospital has increased substantially in the Special Care Nursery as a consequence of a study demonstrating a reduced morbidity and mortality in neonates with necrotizing enterocolitis when treated with vancomycin and cefotaxime. The inability to place more than one peripheral intravenous access necessitates interruption of parenteral nutrition to infuse vancomycin, resulting in a reduction of the planned daily intake of these neonates. This is clinically significant with the administration of vancomycin because of the long administration period required for this drug (60 minutes). This study was designed to assess the physical and chemical stability of vancomycin with a standard neonatal parenteral nutrition solution, Vamin A, when coadministered through the same intravenous line. To simulate the actual clinical setting, the dose of vancomycin and the infusion rate of Vamin A were chosen to represent those commonly used in a 1-kg neonate. Physical compatibility was assessed using effluent obtained after coinfusion of vancomycin with parenteral nutrition solution. Duplicate samples were visually checked for color changes and precipitate. High-pressure liquid chromatography (HPLC) and pH testing were used to assess chemical compatibility of vancomycin. The results of physical compatibility revealed no color change or precipitate. No changes in pH were observed. HPLC determination confirmed that there were no significant time-dependent changes in vancomycin stability. The samples were studied over 24 hours to determine the rate of degradation of vancomycin, if any, under various temperature conditions. The concentrations were not significantly different from each other at the different temperatures studied. Thus, there was no apparent change in the concentration of vancomycin in the presence of Vamin A.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMedDate not supplied

Interference screw fixation strength of a quadrupled hamstring tendon graft is directly related to bone mineral density and insertion torque.

The purpose of this study was to determine whether bone mineral density of the host bone, measured using conventional dual photon absorptiometry techniques, and insertion torque can predict part of the ultimate failure strength of interference screw fixation of quadrupled hamstring tendon grafts. The semitendinosus and gracilis tendons were harvested from 10 human cadaveric knees, mean age 66.5 years (range, 53 to 81). The bone tunnel was sized within 0.5 mm of the graft. The graft was fixed with a biodegradable screw (7 x 25 mm for the femur, and 9 x 25 mm for the tibia) directly against the tendon and at the joint surfaces. Tibial fixation and femoral fixation were tested to failure using a materials testing system. Bone mineral density was measured in the metaphyseal region of the tibia and femur. The results of multiple regression analyses showed that both insertion torque and bone mineral density were related to the maximum load the graft withstood. These two variables explained 77.1% of the maximum load observed. We concluded that bone mineral density measurements of the host bone site are an important determinant of postoperative graft strength and thus have an important, but previously unrecognized, clinical role in establishing individual postsurgery rehabilitation protocols. Insertion torque in this study was a useful predictor of graft fixation strength.

Aged↗
PubMedDate not supplied

Modulation of CD99/MIC2 expression of human AHTO-7 osteoblasts by carcinoma cell line-conditioned media.

BACKGROUND: Prostate cancer metastases induce a predominantly osteoblastic response in bone tissue, resulting in new bone formation and associated morbidity; however, the mechanisms of these tumor-host responses are not fully understood. MATERIALS AND METHODS: Supernatants of prostate (PC3, DU145, LNCaP), breast (BT20, ZR-75-1), colon (SW620, Colo 320DM), pancreatic (ASPC1, Capan-1), renal cell (ACHN) and hepatoma (HepG2) cell lines were tested for their capacity to modulate proliferation, activity of alkaline phosphatase (ALP) and CD99/MIC2 expression in AHTO-7 (large T antigen transfected human trabecular osteoblasts) cells in vitro. RESULTS: Osteoblastic stimulation is not restricted to prostate cancer derived conditioned media CM and high activity is found in CM from Capan-1, HepG2 and ACHN lines. Furthermore these CM down-regulate the expression of the CD99/MIC2 antigen in comparison to medium by AHTO-7 cells as detected by HBA-71 immunofluorescence, with the exception of prostate cancer-derived CM. Induction of the differentiation marker ALP was detected in response to CM derived from Capan-1, BT-20 and Colo320DM. Stimulation of the proliferation of AHTO-7 cells (105-138% of control), induction of ALP (1.17-5.29-fold) and down-regulation of CD99 (13.6-57.5%) exhibited no correlation. CM derived from PC3 and LNCaP metastatic prostate cancer cell lines specifically resulted in the retention/stimulation of the expression of CD99/MIC2 in AHTO-7 cells in contrast to all other cell lines tested. CONCLUSION: The CD99/MIC2 antigen, which is expressed on human osteoblasts and osteosarcoma cells, seems to constitute a new and independent response marker of osteoblasts in the triggering of osteoblastic reaction by prostate cancer cells.

12E7 Antigen↗