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Biomedical subjects

M R Edwards

Publications and source records attributed to M R Edwards.

102 records · Page 6Linked to original sources
PubMed1969

Micromorphological aspects of the development of rubella virus in BHK-21 cells.

Sequential effects of rubella virus infection in BHK-21 cells were studied by electron microscopy of thin sections of control and infected cells, 2 to 7 days after infection. Vacuolization of cytoplasm in Golgi areas apparently preceded budding of virions from vacuole membranes and involvement of the endoplasmic reticulum. Newly formed endoplasmic reticulum cisternae encircled and segregated virionforming vacuoles together with other cellular elements. Large vacuolar complexes with numerous virus particles developed, and virus release from these areas occurred with disruption at the cell periphery. The viral particles, with a mean diameter of about 56 nm, consisted of an electron-dense core surrounded by a less dense capsid, enveloped by a typical unit membrane derived from the vacuole membrane.

Animals↗
PubMed1967

Micromorphology of Cryptococcus neoformans.

Fine details of the internal and external morphology of Cryptococcus neoformans as seen in ultrathin sections are described and illustrated with electron micrographs. The capsule characteristic of this species contained microfibrils (30 to 40 A in diameter) that appeared to radiate from the cell wall and to coil and intertwine in various directions. These thin, uniformly structured, electron-dense filaments are believed to represent complex polysaccharide molecules. The internal morphology of C. neoformans was in many ways similar to that of yeasts studied by other authors. The cell was uninucleate with a single nucleolus. The nuclear envelope, a pair of unit membranes interrupted by pores, was typical of that found in eucaryotic organisms. Smooth endoplasmic reticulum, mitochondria, vacuoles, storage granules, and ribosomes were consistent features of the cytoplasm. In addition, C. neoformans presented membranous organelles derived from the plasma membrane and comparable to bacterial mesosomes and mitochondria of an annulate type.

Cell Wall↗
PubMed1966

Fine Structure of Thiobacillus thiooxidans.

Mahoney, Robert P. (Skidmore College, Saratoga Springs, N.Y.), and Mercedes R. Edwards. Fine structure of Thiobacillus thiooxidans. J. Bacteriol. 92: 487-495. 1966.-Thin section analysis of the chemosynthetic autotroph Thiobacillus thiooxidans revealed structures comparable to gram-negative heterotrophic bacteria. Although this species is unique in that it oxidizes elemental sulfur for energy, uses carbon dioxide as its sole source of carbon, and can withstand a pH of less than 1, thin sections revealed a profile of the cell envelope (cell wall and plasmalemma) similar to other gram-negative species which have more common physiological traits. The cell wall is composed of five layers with an overall width of approximately 200 A, and the plasmalemma appears as a conventional "unit membrane" with a width of about 85 A. Volutin granules and less-dense bodies of similar shape and size were frequently observed in close association with the nucleoplasm. The nature and function of these bodies are unknown at this time.

Journal Article↗
PubMedDate not supplied

Characterisation and sequence analysis of a carbamate kinase gene from the diplomonad Hexamita inflata.

Hexamita inflata can derive energy from the degradation of arginine via the arginine dihydrolase pathway. Carbamate kinase catalyses the third enzymatic step of the pathway synthesising ATP from the catabolism of carbamyl phosphate. This study reports the identification and characterisation of a carbamate kinase gene from this free-living diplomonad, together with measurements of carbamate kinase enzyme activity in cell-free extracts and a preliminary analysis of the carbamate kinase mRNA by reverse-transcription polymerase chain reaction. Analysis of the carbamate kinase gene revealed the use of non-canonical codons for glutamine. Phylogenetic studies showed a consistent close relationship between carbamate kinase sequences of H. inflata and Giardia intestinalis.

Animals↗
PubMedDate not supplied

Characteristics of Norplant users.

OBJECTIVE: To determine whether a profile can be developed to indicate which clients are the best candidates for Norplant by describing the characteristics of clients who use this contraceptive for 5 years and those who have it removed early. DESIGN: A descriptive study of data collected from a convenience sample. SELLING: A state-supported university hospital's obstetric and gynecology outpatient clinic serving primarily indigent clients in the southern United States. PARTICIPANTS: Women (N = 256), primarily with low incomes, being seen for removal of Norplant contraceptive capsules. Of these, 166 women had completed the recommended 5 years. MAIN OUTCOME MEASURES: Characteristics of the clients who retained the contraceptive for the recommended 5 years and characteristics of clients who came for early removal. RESULTS: Clients who retained the contraceptive for 5 years differed from those who did not on only three characteristics: race, age, and parity. No significant differences were found in education or marital status. CONCLUSIONS: No clear profile of successful Norplant users emerged. Instead, thorough counseling of each individual is essential to the client's completion of 5 years with Norplant. Advantages and disadvantages must be explained and the client's tolerance of possible side effects must be assessed, thereby helping the client to make an informed choice.

Adolescent↗
PubMedDate not supplied

Stress: causes, consequences, and coping strategies.

Because of the negative effect stress has on employee health and productivity, ways to manage stress should be of particular concern to human resources managers. Recognizing this, authors Heather R. Sailer, territorial sales representative for American Medical Systems, a division of American Hospital Supply Corporation, John Schlacter, professor of marketing, and Mark Edwards, assistant professor of agriculture--the latter two at Arizona State University--created a model for applying stress-management strategies. Their model integrates seven categories of strategies--two of which are physical maintenance and outside assistance. The model shows at which stage of stress--before, during, or after the stressful event--each strategy can most effectively be used, and in which are of management--self-management, systems management, or organizational management--it is most appropriate.

Burnout, Professional↗
PubMedDate not supplied

Multiple rater performance appraisals: solutions for hospital personnel.

Widely used single rater personnel appraisal systems are not as effective as they should be. Moreover, rater training does not improve ratings based on one person's judgment about an employee. Multiple rater appraisal systems improve accuracy by using the judgments of several knowledgeable people in arriving at a decision. Multiple rater performance appraisals are better than single rater systems because they increase participation; improve accuracy and perceived fairness; provide higher quality management information for selection decisions; supply better Equal Employee Opportunity documentation; give quantitative feedback for employees, appraisers and management; take less management time to complete the performance measurement process and, consequently, improve cost effectiveness.

Employee Performance Appraisal↗