Secreted extracellular acid sphingomyelinase (sASM) activity has been suggested to promote atherosclerosis by enhancing subendothelial aggregation and retention of low-density lipoprotein (LDL) with resultant foam cell formation. Compounds that inhibit sASM activity, at neutral pH, may prevent lipid retention and thus would be expected to be anti-atherosclerotic. With the goal of identifying novel compounds that inhibit sASM at pH 7.4, a high-throughput screen was performed. Initial screening was run using a modification of a proven system that measures the hydrolysis of radiolabeled sphingomyelin presented in detergent micelles in a 96-well format. Separation of the radiolabeled aqueous phosphorylcholine reaction product from uncleaved sphingomyelin lipid substrate was achieved by chloroform/methanol extraction. During the screening campaign, a novel extraction procedure was developed to eliminate the use of the hazardous organic reagents. This new procedure exploited the ability of uncleaved, radiolabeled lipid substrate to interact with hydrophobic phenyl-sepharose beads. A comparison of the organic-based and the bead-based extraction sASM screening assays revealed Z' factor values ranging from 0.7 to 0.95 for both formats. In addition, both assay formats led to the identification of sub- to low micromolar inhibitors of sASM at pH 7.4 with similar IC(50) values. Subsequent studies demonstrated that both methods were also adaptable to run in a 384-well format. In contrast to the results observed at neutral pH, however, only the organic extraction assay was capable of accurately measuring sASM activity at its pH optimum of 5.0. The advantages and disadvantages of both sASM assay formats are discussed.

Drug Evaluation, Preclinical↗

PubMed2004

Genetic and expression profiles of squamous cell carcinoma of the head and neck correlate with cisplatin sensitivity and resistance in cell lines and patients.

PURPOSE: The choice of treatment for squamous cell carcinoma of the head and neck (SCCHN) is still primarily based on the tumor-node-metastasis classification. However, it is reasonable to believe that biological profiles of SCCHN may be independently associated with response to therapy. The aim of the present study was to examine genetic changes and gene expression profiles that might correlate with sensitivity to cisplatin [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay] in 10 SCCHN cell lines. EXPERIMENTAL DESIGN: Five cisplatin-sensitive and five cisplatin-resistant cell lines [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay] were studied by comparative genomic hybridization, spectral karyotyping, and cDNA microarray analysis (21,632 sequence-validated human cDNA; confirmation by reverse transcriptase-PCR for selected genes). For the MET proto-oncogene, which showed low expression in the chemosensitive cell lines, we did immunohistochemical staining on SCCHN of 29 patients who received induction chemotherapy. RESULTS: The five cisplatin-resistant cell lines showed significantly more genetic imbalances (regions of loss and amplification) and chromosomal abnormalities by comparative genomic hybridization and spectral karyotyping, respectively, than did the five cisplatin-sensitive cell lines. Microarray studies identified approximately 60 genes that clearly distinguish between the two groups of cell lines. Some of these genes are known to be involved in tumor progression, metastasis, and drug resistance. We identified low expression of c-met (immunohistochemistry) as a predictive factor for complete response in nondiploid tumors (P = 0.026). CONCLUSIONS: We conclude that cisplatin sensitivity and resistance are related to distinctive differences in the genetic and expression profiles in individual SCCHN tumor cell lines and in SCCHN patients. The genes we have identified may serve as potential targets for novel treatment strategies.

Adult↗

PubMed2004

Clinical management. Where medicine meets management. Acute accent.

There is urgent need for reform in the care of acutely ill medical patients. Problems are being compounded by rising admissions, the reduction in junior doctors' hours and changes in training. Care should be delivered in acute medical or assessment units by dedicated teams specialising in acute care, according to a new report by the Royal College of Physicians.

Acute Disease↗

PubMed2004

Contracts of employment.

Explore the source record for details and available documents.

Contracts↗

PubMed2004

ICF Core Sets for breast cancer.

OBJECTIVE: To report on the results of the consensus process to develop the first version of both a Comprehensive ICF Core Set and a Brief ICF Core Set for breast cancer. METHODS: A formal decision-making and consensus process integrating evidence gathered from preliminary studies was realized. Preliminary studies included a Delphi exercise, a systematic review, and an empirical data collection. After training in the ICF and based on these preliminary studies, relevant ICF categories were identified in a formal consensus process by international experts from different backgrounds. RESULTS: The preliminary studies identified a set of 317 ICF categories at the second, third, and fourth ICF levels with 150 categories on body functions, 44 on body structures, 77 on activities and participation, and 46 on environmental factors. Nineteen experts attended the consensus conference on breast cancer (7 physicians with at least a specialization in physical and rehabilitation medicine, 2 with a specialization in internal medicine and one radiologist, 4 physical therapists, 2 occupational therapists, one psychologist, one epidemiologist and one nurse). Altogether 80 categories (73 second-level and 7 third-level categories) were included in the Comprehensive ICF Core Set with 26 categories from the component body functions, 9 from body structures, 22 from activities and participation, and 23 from environmental factors. The Brief ICF Core Set included a total of 40 second-level categories with 11 on body functions, 5 on body structures, 11 on activities and participation, and 13 on environmental factors. CONCLUSION: A formal consensus process integrating evidence and expert opinion based on the ICF framework and classification led to the definition of ICF Core Sets for breast cancer. Both the Comprehensive ICF Core Set and the Brief ICF Core Set were selected.

Activities of Daily Living↗

PubMed2003

Drop of the hard stuff.

Explore the source record for details and available documents.

Dental Caries↗

PubMed2003

Violence against staff. Government health warning.

Violence against NHS staff is increasing despite four years of zero tolerance. Staff working in community settings can be particularly vulnerable. Many trusts lack robust and consistent reporting mechanisms. NHS anti-fraud service is overhauling reporting system.

Health Personnel↗

PubMed2003