Susan Mitchell

Problem-based learning: a review of literature on its outcomes and implementation issues.

&NA; The effects of problem‐based learning (PBL) were examined by conducting a meta‐analysis‐type review of the English‐language international literature from 1972 to 1992. Compared with conventional instruction, PBL, as suggested by the findings, is more nurturing and enjoyable; PBL graduates perform as well, and sometimes better, on clinical examinations and faculty evaluations; and they are more likely to enter family medicine. Further, faculty tend to enjoy teaching using PBL. However, PBL students in a few instances scored lower on basic sciences examinations and viewed themselves as less well prepared in the basic sciences than were their conventionally trained counterparts. PBL graduates tended to engage in back‐ward reasoning rather than the forward reasoning experts engage in, and there appeared to be gaps in their cognitive knowl‐edge base that could affect practice outcomes. The costs of PBL may slow its implementation in schools with class sizes larger than 100. While weaknesses in the criteria used to assess the outcomes of PBL and general weaknesses in study design limit the confidence one can give conclusions drawn from the literature, the authors recommend that caution be exercised in making comprehensive, curriculum‐wide conversions to PBL until more is learned about (1) the extent to which faculty should direct students throughout medical training, (2) PBL methods that are less costly, (3) cognitive‐processing weaknesses shown by PBL students, and (4) the apparent high resource utilization by PBL graduates. Academic Medicine 68(1993):52–81.

Inhibition of cell migration in sea urchin embryos by β-d-xyloside

Abstract This investigation examines the effect of exogenous xylosides on primary mesenchyme cell behavior in Strongylocentrotus purpuratus embryos. In confirmation of studies in some other species the addition of 2 mM, p-nitrophenyl-β- d -xylopyranoside blocks the migration but not the initial ingression of primary mesenchyme cells. The blastocoel matrix of treated embryos appears deficient in a 15- to 30-nm-diameter granular component that is observed extensively on the basal lamina and on filopodia of migrating primary mesenchyme cells in untreated embryos. Other blastocoel components appear unaffected by ultrastructural criteria. The incorporation of 35SO2−4 per embryo into ethanol precipitates of isolated blastocoel matrices was reduced significantly after xyloside treatment but the distribution of 35SO2−4 after polyacrylamide gel electrophoresis or the glycosaminoglycan composition was unaffected. Chromatography on Sepharose CL-2B demonstrates a reduction in size of sulfated components of the blastocoel. While over 60% of the 35S-labeled material from the blastocoel of normal mesenchyme blastulae is voided from a Sepharose CL-2B column run in a dissociative solvent, only 10% from xyloside treated embryos is voided. Instead, there is a large included peak with Kav of 0.33. This material is acid soluble but cetylpyridinium chloride precipitable. It apparently consists largely of free glycosaminoglycan chains. Based on analysis of chondroitinase ABC digestion products this material consists of 41% chondroitin-6-sulfate and 58% dermatan sulfate. These results are consistent with a role in cell migration for intact chondroitin sulfate/dermatan sulfate proteoglycans in the sea urchin blastocoel matrix.

Evaluation of a geriatric mental health training program for nursing personnel in rural long-term care facilities

Although mental illness among elderly living in nursing homes is a substantial and growing concern, the behavioral problems associated with mental illness or threats to mental health are not well understood, tolerated, or effectively managed by nursing home staff. As a result, resident care and quality of life, and staff morale often suffer. The need for geriatric mental health training in long-term care settings has become increasingly apparent. Psychiatric/mental health nurses are in an advantageous position to address this current need and future challenge through the development, implementation, and evaluation of geriatric mental health education and training programs in long-term care settings. This article describes one such innovative training effort, designed to improve the quality of psychosocial care provided by nursing personnel in rural long-term care settings, and highlights evaluation outcomes related to participant satisfaction, staff knowledge, and attitudes.

Protochlorophyllide photoconversion mutants of Chlamydomonas reinhardtii

SummaryWe have developed a procedure for the isolation of Chlamydomonas reinhardtii mutants defective in light-dependent protochlorophyllide reduction (photoconversion), a key step in the biosynthesis of chlorophyll. Mutants were isolated by mutagenizing y-1-4, a temperature-sensitive yellow mutant blocked in the alternative light-independent protochlorophyllide reduction pathway, and screening for colonies which failed to green in the light at the restrictive temperature. Seven mutants were isolated which fail to photoconvert protochlorophyllide in photoconversion tests. All seven mutants have a single mutation at the pc-1 locus responsible for the defect in photoconversion. pc-1 maps close to y-5 on nuclear linkage group I. The pc-1 mutation is not itself temperature-sensitive because it blocks photoconversion at the permissive temperature when combined with the non-conditional yellow mutations y-5 and y-7. Cells containing the pc-1 mutation alone synthesize about 52% and 36% of the wildtype chlorophyll level in the dark and light, respectively, demonstrating that the light-independent protochlorophyllide reduction pathway in C. reinhardtii operates in the light.

Geropsychiatric nursing consultation: A valuable resource in rural long-term care☆

Psychiatric and geropsychiatric nurse specialists have the potential to positively influence the day-to-day care provided in rural nursing homes by acting as teachers, resource persons, facilitators, and role models to long-term care (LTC) personnel. The combined approach of training LTC nurses to train their own staff while supporting the application of learning with consultee-focused nursing consultation proved to be an effective and time-efficient method of improving the geropsychiatric nursing care provided in rural nursing homes.

Characterization of NADPH: Protochlorophyllide oxidoreductase in the y-7 and pc-1 y-7 mutants of Chlamydomonas reinhardtii

SummaryProtochlorophyllide (Pchilide) photoconversion, a key step in the biosynthesis of chlorophyll, is catalyzed by the enzyme NADPH: Pchlide oxidoreductase. We have previously shown that the pc-1 mutation of Chlamydomonas reinhardtii causes a defect in photoconversion in vivo. The double mutant pc-1 y-7 failed to photoconvert Pchlide to chlorophyllide, whereas the yellow mutant y-7 showed normal photoconversion (Ford et al. 1981). We have now obtained similar results in vitro, using detergent solubilized membrane preparations. The enzyme activity in y-7 preparations had a pH optimum of 8.5 and had a stringent requirement for both NADPH and Pchlide. We have partially purified the enzyme activity from y-7 by gel filtration. Photoconversion activity eluted with a 320,000 dalton membrane-protein aggregate. Pchlide eluted in two peaks, one of which co-eluted with the enzyme activity peak. Corresponding column fractions from pc-1 y-7 showed similar protein and Pchlide elution profiles, but no enzyme activity. These results suggest that NADPH: Pchlide oxidoreductase is present, but inactive, in the double mutant, and are consistent with the hypothesis that the pc-1 locus codes for the enzyme.

Nurses helping nurses: development of internal specialists in long-term care.

1. Too often, expert assistance provided by psychiatrists and psychiatric nurse specialists to long-term care (LTC) providers of geriatric patients is short-lived and not effective in helping LTC staff deal with their patients behavioral and psychological problems. 2. One of the main objectives of the study--and one that was found to have positive results--was to provide a mechanism by which LTC staff could develop their own expertise in the management of behaviorally difficult residents. 3. More collaborative efforts among nursing specialists, subspecialists, and generalists are needed to empower those who work in LTC to utilize the abilities and strengths inherent in their positions.