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Biomedical subjects

A Morgan

Publications and source records attributed to A Morgan.

305 records · Page 17Linked to original sources
PubMedDate not supplied

In vitro and in vivo antineoplastic effects of orthovanadate.

In the present study we have demonstrated that orthovanadate at concentrations of 5-10 uM is cytotoxic to proliferating cells including primary cultures and tumour cell lines. However, concentrations of up to 50 uM did not affect the viability of non-proliferating cells. The cytotoxicity appears to be dependent on the vanadium concentration rather than on the oxidation state of vanadium or the vanadium compound. Furthermore, tumour cell lines with different proliferative rates were equally sensitive to orthovanadate cytotoxicity. Although the mechanisms responsible for the cytotoxicity are not known, addition of H2O2 potentiated orthovanadate cytotoxicity suggesting that hydroxyl or vanadium radicals may be involved. In vivo subcutaneous injections of orthovanadate into mice containing MDAY-D2 tumours resulted in the inhibition of tumour growth by 85-100%. These data indicated that orthovanadate at concentrations greater than 5 uM has antineoplastic properties and may be useful as a chemotherapeutic agent.

Animals↗
PubMedDate not supplied

The identification of cDNA clones that include the 3' end of mRNA.

A method is presented that facilitates the identification of cDNA clones corresponding to the polyadenylated 3' end of mRNA. It is based on the use of a poly dT probe that is synthesized by homopolymer extension of commercially available oligo dT. The method is shown to work in Southern blot analysis of plasmid preparations and in situ with colonies.

Blotting, Southern↗
PubMedDate not supplied

Oxygenating mouthguard alleviates hypoxia during gastroscopy.

A randomized study was carried out to determine the effect of oxygen (3 liters/min) via a novel oxygenating mouthguard (Oxyguard) on arterial oxygenation in 242 intravenously sedated patients undergoing gastroscopy. In another group of 21 patients, a randomized crossover study of arterial oxygen saturation using either the standard mouthguard or the oxygenating mouthguard (3 liters/min) was conducted. Significant O2 desaturation (pulse oximeter reading less than 90%) occurred in 25% of patients on room air but only 3% of those on oxygen (p less than 0.001). Severe desaturation (reading less than 85%) occurred in 5% of patients on room air but was prevented by the oxygenating mouthguard. Minimum oxygen saturation levels were significantly higher in patients on oxygen (90.5 +/- 0.3%) than on air (86.5 +/- 0.5%; p less than 0.001). In the crossover group, O2 saturation was uniformly higher in the recordings of all patients using the oxygenating mouthguard. In conclusion, administration of oxygen via the oxygenating mouthguard alleviates hypoxemia during gastroscopy and prevents severe oxygen desaturation. However, hypoxemia may occur even during use of supplemental oxygen. Hence, monitoring of arterial oxygenation is recommended.

Equipment Design↗
PubMedDate not supplied

Calcium sensors in regulated exocytosis.

Neurotransmitter release, hormone secretion and a variety of other secretory process are tightly regulated with exocytotic fusion of secretory vesicles being triggered by a rise in cytosolic Ca2+ concentration. A series of proteins that act as part of a conserved core machinery for vesicle docking and fusion throughout the cell have been identified. In regulated exocytosis this core machinery must be controlled by Ca(2+)-sensor proteins that allow rapid activation of the fusion process following elevation of cytosolic Ca2+ concentration. The properties of such Ca2+ sensors are known from physiological studies but their molecular identity remains to be unequivocally established. The multiple Ca(2+)-dependent steps in the exocytotic pathway suggest the likely involvement of several Ca(2+)-binding proteins with distinct properties. Functional evidence for the role of various Ca(2+)-binding proteins and their possible sites of action is accumulating but a definitive identification of the major Ca(2+)-sensor in the final step of Ca(2+)-triggered membrane fusion in different cell types awaits further analysis.

Animals↗
PubMedDate not supplied

Health teaching in clinical nursing practice.

The Nurses' Board of Western Australia identifies health teaching as one of five essential role competencies in its regulation of professional nursing practice. This implies that patient/client education is recognized as a fundamental component of health care, however there is mounting concern within the profession that nurses are not taking full advantage of teaching opportunities that present in clinical practice. This paper reviews literature about health teaching and suggests that patients should be better informed about their health status and future health maintenance.

Health Education↗
PubMedDate not supplied

Interactive assessment in a nursing program.

Diversification of assessment in nursing education is essential to the success of determining program efficacy. Critics claim that traditional methods of educational measurement are a useful means of providing feedback on student achievement, but these methods tell us very little about the significant transition students go through as they are exposed to unpredictable teaching and learning processes. This paper describes the development of an innovative approach to assessment that integrates the traditional outcome objective model with a process-oriented initiative that fosters ongoing reflection upon educational experiences.

Clinical Competence↗