Understanding perceptions of nursing professional identity in students entering an Australian undergraduate nursing degree.

Developing a professional identity is an essential transition for nursing students as they move through their undergraduate degree. Professional identity is described as a person's perception of themselves within a profession or the collective identity of the profession. The formation of a professional identity is an evolving process, shaped by the media, educational experiences and role modelling. The aim of this study was to develop a greater understanding of the perceptions that students, about to embark on their undergraduate nursing degree, had of the nursing profession. A drawing and mind mapping exercise was conducted with a convenience sample of commencing nursing students to explore how they viewed their future profession. The data underwent thematic analysis and then grouped into sub-themes and themes. Four key themes were identified, 'To be a nurse, I have to look the part', 'To be a nurse, I have to perform in a variety of roles', 'To be a nurse, I have to connect with others', and 'To be a nurse, I have to care for myself.' The formation of a strong pre-professional identity is important for nursing students due to the link between future job satisfaction and the development of a robust nursing workforce.

Mycobacterium tuberculosis lineage: a naming of the parts.

There have been many reports of groups of related Mycobacterium tuberculosis strains described variously as lineages, families or clades. There is no objective definition of these groupings, making it impossible to define relationships between those groups with biological advantages. Here we describe two groups of related strains obtained from an epidemiological study in Tanzania, which we define as the Kilimanjaro and Meru lineages on the basis of IS6110 restriction fragment length polymorphism (RFLP), polymorphic GC rich sequence (PGRS) RFLP and mycobacterial interspersed repeat unit (MIRU) typing. We investigated the concordance between each of the typing techniques and the dispersal of the typing profiles from a core pattern. The Meru lineage is more dispersed than the Kilimanjaro lineage and we speculate that the Meru lineage is older. We suggest that this approach provides an objective definition that proves robust in this epidemiological study. Such a framework will permit associations between a lineage and clinical or bacterial phenomenon to be tested objectively. This definition will also enable new putative lineages to be objectively tested.

Microassay for rapid screening of alpha-amylase activity.

A microassay was developed for measuring the activity of alpha-amylases in the nanogram enzyme concentration range, based on the use of dye-labeled cross-linked starch as the substrate, and the release of soluble colored fragments formed in enzyme hydrolysis. Reaction conditions were optimized to generate a linear correlation between the increase in absorbance and a reaction time of 0-10 min, as well as enzyme concentrations in the range of 0-50 ng. A standard curve for the conversion of absorbance to enzyme activity units was constructed. The protocol developed was applied to monitoring the production of ultralow concentrations of recombinant barley alpha-amylase in yeast cells.

Advocacy groups for breast cancer patients.

Breast cancer patient advocacy groups emerged in the 1990s to support and empower women with breast cancer. Women with cancer and oncologists tend to have divergent perspectives on how breast cancer prevention should be defined and what the priorities for research should be. As their American counterparts have done, breast cancer patient advocates in Canada are seeking greater participation in decision making with respect to research. To date they have had more input into research policy decisions than into the planning of specific projects. In 1993 the National Forum on Breast Cancer recommended that women with breast cancer should have more input into the research process; breast cancer patient advocates will continue to actively pursue this objective.

Separation and localization of two classes of auxin binding sites in corn coleoptile membranes.

Further evidence is presented for the discrete nature of the two classes of high affinity auxin binding sites in corn (Zea mays L.) coleoptile membranes, site 1 and site 2. Fractions can be obtained by differential centrifugation that exhibit binding kinetics characteristic of site 2, but not site 1. Membrane preparations containing both binding sites may be resolved on sucrose gradients into a light and a heavy band, whose binding kinetics and analogue binding specificities correspond to those deduced for site 1 and site 2 respectively in unfractionated membranes. Evidence from enzymic and chemical assays and from electron microscopy suggests that site 2, the auxin-specific binding site, is located in fractions enriched in plasma membrane, whereas site 1 is associated with Golgi membranes and/or endoplasmic reticulum.

Contextual factors related to the drinking behaviors of American business and professional women.

American women in business and professional occupations (n = 453) completed a survey that included questions on alcohol use, drinking context, and work and other activities. Spouses' and best friends' consumption and subjects' frequency in drinking settings correlated with their consumption and negative consequences of alcohol use. Multiple regression analyses indicated that predictor variables for consumption were frequency in drinking settings, a measure of three personal motives for drinking, age, and number of organization memberships. Predictor variables for negative consequences were subject's consumption, spouse's drinking, frequency in drinking settings, and age. The results suggest that social context may be important in understanding women's drinking. Variables directly related to drinking, such as time spent in drinking situations, are correlated with increased drinking, while other contextual variables, such as membership in organizations, may play a preventive role.

Auxin binding to corn coleoptile membranes: Kinetics and specificity.

Detailed examination of binding over the range 10(-7)-10(-6) M suggests that membrane preparations from coleoptiles of Zea mays L., cv Kelvedon 33 contain at least two sets of high affinity binding sites for 1-naphthylacetic acid (NAA), with dissociation constants of 1.8×10(-7) M (site 1) and 14.5×10(-7) M (site 2). Similar studies with 3-indolylacetic acid (IAA) also indicate two sets of binding sites, whose concentrations are closely comparable to those deduced for NAA. A substantial proportion of the total binding activity is retained in a detergent-solubilized preparation. Using [(14)C]NAA the interactions of a range of analogues with each of the binding sites have been examined with the aid of double reciprocal plots. The specificity of site 2 is compatible with that expected for an auxin receptor, in that only active auxins, antiauxin transport inhibitors are able to compete with [(14)C]NAA for the binding sites. Site 1 on the other hand is less specific, since it appears to bind all compounds tested, including physiologically inactive analogues.

Characterization of active barley alpha-amylase 1 expressed and secreted by Saccharomyces cerevisiae.

Recombinant barley alpha-amylase 1 isozyme was constitutively secreted by Saccharomyces cerevisiae. The enzyme was purified to homogeneity by ultrafiltration and affinity chromatography. The protein had a correct N-terminal sequence of His-Gln-Val-Leu-Phe-Gln-Gly-Phe-Asn-Trp, indicating that the signal peptide was efficiently processed. The purified alpha-amylase had an enzyme activity of 1.9 mmol maltose/mg protein/min, equivalent to that observed for the native seed enzyme. The kcat/Km was 2.7 x 10(2) mM(-1) x s(-1), consistent with those of alpha-amylases from plants and other sources.

Isolation of a raw starch-binding fragment from barley alpha-amylase.

Barley alpha-amylase was purified by ammonium sulfate fraction, ion-exchange, ultrafiltration, and gel filtration to homogeneity. The purified enzyme was partially digested with trypsin, and the reaction mixture was applied to a cyclohepta-amylose epoxy Sepharose 6B column. Bound fragments were eluted by free cyclohepta-amylose, lyophilized, and separated on Tricine gels. Four fragments were shown to interact with beta-cyclodextrin. The fragment that could be identified on the gel with the lowest molecular weight (11 kDa) was electroblotted onto PVDF membrane for sequencing. The N-terminal sequence of this fragment was determined with the N-terminal amino acid corresponding to Ala283 in the whole protein. The trypsin cleavage was at Lys282/Ala283 and the C-terminal cleavage occurred at Lys354/Ile355 to give a fragment size of 11 kDa as estimated by SDS-PAGE. The fragment would be located at the C-terminal region, forming a majority of the antiparallel beta-sheets in domain C and the alpha7- and alpha8-helices of the (alpha/beta)8 domain.

Effect of feeding of a cholesterol-reducing bacterium, Eubacterium coprostanoligenes, to germ-free mice.

Twelve germ-free mice were used to evaluate the effect of orally administered Eubacterium coprostanoligenes (ATCC 51222) on serum cholesterol concentration. After 1 week of bacterial administration, serum cholesterol concentration of the experimental group (204.9 +/- 5.3 mg/dl, mean +/- SEM) tended to be lower than that of controls (213.7 +/- 5.9 mg/dl, mean +/- SEM). The hypocholesterolemic effect, however, was transient. Greater coprostanol-to-cholesterol ratios in feces of bacteria-fed mice also indicated a transient cholesterol-reducing action of E. coprostanoligenes in the intestine. Eubacterium coprostanoligenes did not colonize the intestine of E. coprostanoligenes-fed mice. Results indicate that the transient occurrence of E. coprostanoligenes in the digestive tract of E. coprostanoligenes-fed mice may decrease plasma cholesterol concentration, but colonization of the tract depends on monoassociation with another bacterium. Results also indicate that feeding of E. coprostanoligenes decreases blood cholesterol concentration.

Quantitative validation of media for transportation and storage of Streptococcus pneumoniae.

The need to design effective Streptococcus pneumoniae vaccines and to monitor resistance means that it is essential to have efficient methods to determine carriage rates. Two liquid media, consisting of skim milk, glycerol, glucose, and tryptone soya broth (STGG) or skim milk, glycerol, and glucose (SGG) alone, were evaluated for their ability to maintain pneumococcal viability. Optimal recovery of S. pneumoniae was achieved when swabs were transferred to STGG medium prior to plating onto blood agar-gentamicin selective plates (22%) compared to 7% when plated out directly (P < 0.0001 by Fisher's exact test). Both STGG and SGG media are appropriate for the long-term storage of pneumococci and primary swab samples at -70 degrees C, with no decrease in viable count observed following repeated freeze-thaw cycles. Samples could be stored refrigerated for up to 3 days in either STGG or SGG medium with no significant loss of viability. Viability decreased progressively in storage at 20 to 30 degrees C, with greater losses of viability occurring at the higher temperatures. There were no significant differences in viability between isolates in the two media. STGG preserved pneumococci significantly better (about twofold) than SGG medium at 21 degrees C (P < 0.0001) and 30 degrees C (P < 0.0001). Samples can be stored for 4 and 2.5 days at 6 to 8 degrees C, 28 and 17 h at 21 degrees C, and 15 and 7 h at 30 degrees C in STGG and SGG media, respectively. For field studies undertaken in resource-limited environments, SGG medium can be prepared by using locally available materials. The quantitative data reported in this study will enable researchers to plan appropriate transport and storage protocols.

Quantitative determination of plasma c8-c26 total fatty acids for the biochemical diagnosis of nutritional and metabolic disorders.

We have developed a capillary gas chromatography-electron-capture negative-ion mass spectrometry (GC/MS) method for the quantitative determination of C8-C26 total fatty acids in plasma. Following hydrolysis, hexane extraction, and derivatization with pentafluorobenzyl bromide, fatty acid esters are analyzed in two steps: a splitless injection and a second, split injection (1:100) for the quantitation of the more abundant long-chain species. Fourteen saturated and 25 unsaturated fatty acids are quantified by selected ion monitoring in ratio to 13 stable-isotope-labeled internal standards. Calibrations exhibit consistent linearity and reproducibility. Intraassay (n = 17) and interassay (n = 12) CVs ranged from 2.5 to 13.2% and from 4.6 to 22.9%, respectively. Recoveries ranged from 76 to 106%. Reference ranges were established for four age groups (<1 month, 1 month to 1 year, 1-17 years, >18 years) and compared to specimens from patients with nutritional deficiency of omega-3 and omega-6 polyunsaturated fatty acids, inborn errors of mitochondrial fatty acid oxidation, and peroxisomal disorders. Retrospective evaluation of the concentration of linoleic acid in 35 cases with a diagnosis of essential fatty acid deficiency previously made by gas chromatographic analysis with flame ionization detection (GC/FID) found a specificity and sensitivity of only 55 and 50%, respectively, for the GC/FID method when compared to GC/MS.