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Thomas Russell

Publications and source records attributed to Thomas Russell.

5 recordsLinked to original sources
PubMed2006

Relative contributions of surgeons and decision support systems.

Evidence-based medicine came into focus in 1992 when scholars recognized the need for valid information required for optimal patient care. Because of the increasing volume and uncertain quality of new knowledge, traditional sources of information such as books and journals failed to meet the needs of busy practitioners.Evidence-based medicine promoted strategies for identifying and appraising relevant information and making it readily available. Surgeons face unique challenges in the recognition and application of best evidence. Evidence-based surgery requires careful appraisal of the existing evidence, expanding the pool of level 1 evidence,and improving the availability of best evidence. Ultimately, the organization of systems will incorporate best evidence into the processes of care and will document the outcomes of care.

Decision Support Systems, Clinical↗
PubMed2005

Expression of epithelial cell adhesion molecule in carcinoma cells present in blood and primary and metastatic tumors.

The epithelial cell adhesion molecule (EpCAM) is involved in homophilic cell-cell adhesion in normal epithelia and is frequently overexpressed in primary and metastatic adenocarcinomas. It has been postulated that during detachment and dissemination of tumor cells, EpCAM may be down-regulated. Circulating tumor cells (CTC) may demonstrate this phenomenon as they have successfully escaped their local microenvironment and entered the circulation. EpCAM expression of CTC was compared to tumor cells in paraffin-embedded tissue arrays containing various benign diseases and carcinomas. EpCAM expression on CTC was determined by flow cytometry (FCM) and by immunohistochemistry (IHC) in paraffin-embedded tissue. To permit comparison of FCM results to those derived by IHC, EpCAM was quantified on cancer cell lines by FCM and then paraffin-embedded cell-blocks of these lines were used as staining guides for IHC analysis of tissue arrays. By IHC, 97% (384/397) of solid tissues analyzed had detectable EpCAM, with 72% of tissues showing antigen expression levels of > or =400,000 EpCAM molecules per cell. FCM analysis of CTC from 100 metastatic carcinoma patients with > or =2 CTC/90 microl blood showed EpCAM expression ranging from 9,900 to 246,000 (mean 49,700) antigens per cell. EpCAM expression was approximately 10-fold lower on CTC as compared to primary and metastatic tissues, suggesting that EpCAM expression is transient and dependent upon the local micro-environment. This supports the hypothesis that this adhesion molecule is down-regulated on carcinoma cells in the circulation.

Animals↗
PubMed2004

Brain death.

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Brain Death↗
PubMed2004

Apoptosis of circulating tumor cells in prostate cancer patients.

BACKGROUND: The prescence of circulating tumor cells (CTCs) in the peripheral blood of cancer patients and their frequency has been correlated with disease status. METHODS: In this study, CTCs were characterized by flow cytometry and fluorescence microscopy after immunomagnetic enrichment from 7.5-ml blood samples collected from patients with prostate cancer in evacuated blood-draw tubes that contained an anticoagulant and a preservative. Events were classified as tumor cell candidates if they expressed cytokeratin, lacked CD45, and stained with the nucleic acid dye 4,6-diamidino-2-phenylindole. RESULTS: In the blood of prostate cancer patients, only few of these events were intact cells. Other CTC events appeared as damaged cells or cell fragments by microscopy. By flow cytometry, these events stained variably with 4,6-diamidino-2-phenylindole and frequently expressed the apoptosis-induced, caspase-cleaved cytokeratin 18. Similar patterns of cell disintegration were observed when cells of the prostate line LNCaP were exposed to paclitaxel before spiking the cells into normal blood samples. CONCLUSIONS: The different observed stages of tumor cell degradation or apoptosis varied greatly between patients and were not found in blood of normal donors. Enumeration of CTCs and identification of CTCs undergoing apoptosis may provide relevant information to evaluate the response to therapy in cancer patients.

Adenocarcinoma↗