Biomedical subjects
Publications and source records attributed to M L Lewis.
The University of Minnesota has developed a limited-cohort distance education graduate program to overcome geographic barriers and address the shortage of master's-prepared specialty nurses in rural areas of the upper Midwest. Such a program offers graduate nursing education in various specialty areas to distance sites for a predetermined, relatively short period.
The cytoskeleton is a complex network of fibers that is sensitive to environmental factors including microgravity and altered gravitational forces. Cellular functions such as transport of cell organelles depend on cytoskeletal integrity; regulation of cytoskeletal activity plays a role in cell maintenance, cell division, and apoptosis. Here we report cytoskeletal and mitochondria alterations in cultured human lymphocyte (Jurkat) cells after exposure to spaceflight and in insect cells of Drosophila melanogaster (Schneider S-1) after exposure to conditions created by clinostat rotation. Jurkat cells were flown on the space shuttle in Biorack cassettes while Schneider S-1 cells were exposed to altered gravity forces as produced by clinostat rotation. The effects of both treatments were similar in the different cell types. Fifty percent of cells displayed effects on the microtubule network in both cell lines. Under these experimental conditions mitochondria clustering and morphological alterations of mitochondrial cristae was observed to various degrees after 4 and 48 hours of culture. Jurkat cells underwent cell divisions during exposure to spaceflight but a large number of apoptotic cells was also observed. Similar results were obtained in Schneider S-1 cells cultured under clinostat rotation. Both cell lines displayed mitochondria abnormalities and mitochondria clustering toward one side of the cells which is interpreted to be the result of microtubule disruption and failure of mitochondria transport along microtubules. The number of mitochondria was increased in cells exposed to altered gravity while cristae morphology was severely affected indicating altered mitochondria function. These results show that spaceflight as well as altered gravity produced by clinostat rotation affects microtubule and mitochondria organization and results in increases in apoptosis. Grant numbers: NAG 10-0224, NAG2-985.
The healthcare environment is changing at an unprecedented pace. To be prepared adequately to respond to these demands in healthcare, nurses must exhibit flexibility, creativity, independence, critical thinking, leadership, and collaboration. The authors describe an honors program and the teaching strategies used to enhance several of these characteristics. These strategies can be tailored for students in non-honors programs to develop the attributes required of baccalaureate nursing graduates.
Explore the source record for details and available documents.
A method of measuring pulmonary arterial transit time (PATT), from the pulmonary valve to the precapillary vessels, using the gamma-emitting isotope technetium-99m and external counting probes, has been applied in patients coming to cardiac catheterization. The method was successfully applied in 36 of 39 patients. The dose of 99Tc for a single determination was 1 mc. Agreement between right and left lung transit times was good, average difference between the two lungs being less than 7% of mean PATT. Reproducibility between duplicate injections was 9.4 +/- 1.2% (SEM). Pulmonary arterial volume (PAV) was calculated as the product of PATT and flow. In 11 normal patients average PAV was 92 ml . m-2 and constituted 30% of total pulmonary blood volume (PBV). In ten patients with pulmonary hypertension secondary to lung disease average PAV was 129 ml . m-2, constituting 38% of PBV, while, in seven patients with left ventricular disease and a similar degree of pulmonary hypertension, PAV was also 129 ml . m-2, but constituted only 29% of PBV. Thus, in pulmonary hypertension secondary to lung disease the pulmonary arteries are enlarged out of proportion to the remainder of the pulmonary vascular bed. In seven patients with carcinoma of the lung, in whom one main branch of the pulmonary artery was occluded with a balloon catheter, PAV fell significantly less than would be predicted, indicating a distension of the unoccluded portion of the arterial tree. Distensibility in the unoccluded part of the arterial tree was calculated to be 4.5% per cmH2O pressure.