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Raymond Playford

Publications and source records attributed to Raymond Playford.

3 recordsLinked to original sources
PubMed2006

Characterization and clinical application of human CD34+ stem/progenitor cell populations mobilized into the blood by granulocyte colony-stimulating factor.

A phase I study was performed to determine the safety and tolerability of injecting autologous CD34(+) cells into five patients with liver insufficiency. The study was based on the hypothesis that the CD34(+) cell population in granulocyte colony-stimulating factor (G-CSF)-mobilized blood contains a subpopulation of cells with the potential for regenerating damaged tissue. We separated a candidate CD34(+) stem cell population from the majority of the CD34(+) cells (99%) by adherence to tissue culture plastic. The adherent and nonadherent CD34(+) cells were distinct in morphology, immunophenotype, and gene expression profile. Reverse transcription-polymerase chain reaction-based gene expression analysis indicated that the adherent CD34(+) cells had the potential to express determinants consistent with liver, pancreas, heart, muscle, and nerve cell differentiation as well as hematopoiesis. Overall, the characteristics of the adherent CD34(+) cells identify them as a separate putative stem/progenitor cell population. In culture, they produced a population of cells exhibiting diverse morphologies and expressing genes corresponding to multiple tissue types. Encouraged by this evidence that the CD34(+) cell population contains cells with the potential to form hepatocyte-like cells, we gave G-CSF to five patients with liver insufficiency to mobilize their stem cells for collection by leukapheresis. Between 1 x 10(6) and 2 x 10(8) CD34(+) cells were injected into the portal vein (three patients) or hepatic artery (two patients). No complications or specific side effects related to the procedure were observed. Three of the five patients showed improvement in serum bilirubin and four of five in serum albumin. These observations warrant further clinical trials.

Antigens, CD34↗
PubMed2003

GERD 2003 -- a consensus on the way ahead.

Gastroesophageal reflux disease (GERD) has in recent times become an important public health issue owing to the considerable health care resources utilized in its management, its deleterious effect on quality of life and the increasing prevalence of a relatively rare complication of reflux disease - esophageal adenocarcinoma. We review here the major current challenges in the field of reflux disease and its complications, and provide some approaches that may be useful in management. The issues to be faced include the very limited comprehension of the reasons behind the increasing prevalence of the disease, difficulties in correlating symptoms with objective data of pathological gastroesophageal reflux and the relatively unsophisticated tools we are employing to investigate the underlying pathophysiology. It is certain that the lack of well-defined and characterized methodologies to compare the effects of therapy require the development of more effective questionnaire-type analytic tools. In regard to treatment, there is little doubt that the widely prescribed proton pump inhibitors have dose-equivalent efficacy and are the most highly effective agents capable of suppressing acid, controlling many of the symptoms of GERD and healing erosions. Nevertheless, many patients continue to experience symptoms on withdrawal or at night. Pharmacological agents that can effectively increase lower esophageal sphincter pressure or promote motility are as yet unavailable. Although the introduction of laparoscopic techniques has resulted in a modest revival in surgical intervention using a variety of 'wrap-type' operations, the indications are few and the procedure is associated with a significant morbidity and even mortality especially if the expertise of the surgeon is an issue. Endoscopic techniques of regulating reflux are at this time experimental and not applicable to the general population. Intestinal metaplasia in the lower esophagus is probably very common. Whether and how to, first, screen for, and then, perform surveillance in Barrett's esophagus remains highly problematic and contentious.

Barrett Esophagus↗