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HENDERSON A., BRIGGS J., SCHOONBEEK S., & PATERSON K. (2011) A framework to develop a clinical learning culture in health facilities: ideas from the literature. International Nursing Review, 196-202 Internationally, there is an increase in demand to educate nurses within the clinical practice environment. Clinical practice settings that encourage teaching and learning during episodes of care delivery can be powerful in educating both the existing nursing workforce and nursing students. This paper presents a framework, informed by the literature, that identifies the key factors that are needed to encourage the interactions fundamental to learning in clinical practice. Learning occurs when nurses demonstrate good practice, share their knowledge through conversations and discussions, and also provide feedback to learners, such as students and novices. These types of interactions occur when positive leadership practices encourage trust and openness between staff; when the management team provides sessions for staff to learn how to interact with learners, and also when partnerships provide support and guidance around learning in the workplace. This framework presents how the concepts of leadership, management and partnership interact to create and sustain learning environments. The feedback from proposed measurement tools can provide valuable information about the positive and negative aspects of these concepts in the clinical learning environment. Analysis of the subscales can assist in identifying appropriate recommended strategies outlined in the framework to guide nurses in improving the recognized deficits in the relationship between the concepts. Leadership, management and partnerships are pivotal for the creation and maintenance of positive learning environments. Diagnostic measurement tools can provide specific information about weaknesses across these areas. This knowledge can guide future initiatives. [ABSTRACT FROM AUTHOR]

Determinants of the balance between grass and woody vegetation in grasslands and savannas have received considerable attention because of the potential for dramatic shifts in ecosystem structure and function as one growth form replaces the other. We studied a mesic grassland where recently established "shrub islands" are increasing in abundance due to fire suppression. Our objective was to assess the role of the direct effects of fire vs. indirect alterations in resource availability (N and light), as mechanisms that may constrain/facilitate shrub (Cornus drummondii) encroachment. The direct effects of fire in 2001 and 2002 were 100% aboveground mortality of C. drummondii shoots and removal of the detrital layer. Post-fire resprouting resulted in ∼600% increase in stem density compared to a 200% increase in shrub islands protected from fire. In burned shrub islands with an added detrital layer, temperature and light penetration to the soil surface were reduced (by 6.5°C and to <3% of full sunlight), but stem density still increased by ∼400%. Thus, both the direct effects of fire and the indirect effect on the energy environment increased C. drummondii stem densities. In contrast, N additions did not influence new stem production or aboveground net primary productivity (ANPP; grams per square meter per year), suggesting that N availability did not constrain shrub growth during this study. While fire did not impact total ANPP, it did shift the relative abundance of growth forms. Grass productivity (360.7 ± 20.1 g/m² [mean ± 1 SE]) was stimulated (an increase of ∼30%) by the high light conditions of the post-fire environment, while C. drummondii ANPP (34.2 ± 2.4 g/m²) was reduced by ∼30%. In shrub islands protected from fire, C. drummondil ANPP was greatest (50.4 ± 2.2 g/m²), whereas lower graminoid ANPP (282.5 ± 19.9 g/m²) was observed. The persistence of woody vegetation, despite two successive fires, along with a significant reduction in grass ANPP (∼30%) suggests that once established, C. drurnmondii can persist and exclude C4 grasses. Thus, restoring fire to mesic grasslands may prevent further conversion to shrub/woodland, but the abundance of shrubs is likely to remain unchanged with community structure co-dominated by multiple growth forms. [ABSTRACT FROM AUTHOR]

Production patterns of tallgrass prairie and adjacent eastern deciduous forest were summarized for a five to seven year period. Each system responded differentially to annual or growing season rainfall and solar energy (measured by pan water evaporation). Overall, forest productivity was negatively correlated with annual precipitation; the prairie exhibited no relationship with precipitation. These differences probably reflect the lack of water limitation of the forest and the "downstream" position of the forest. Wood and seed production in the forest were the most variable components measured in our study. Neither variable was related to forest foliage production. Seed production in the prairie was also variable within and between years but was related to prairie foliage production. Prairie seed production was not correlated with seed production of the forest. The two ecosystems respond differentially and independently of each other within the range of climatic variation observed here. Such differences have potential significance to consumers who use both systems for habitat or resources. [ABSTRACT FROM AUTHOR]

Narcissus bulbs were treated with various concentrations of formaldehyde in hot water at different times relative to lifting and planting. There was no improvement in control of Fusarium oxysporum basal rot by using formaldehyde concentrations greater than the usual 0.2 per cent. The date of treatment was critical, and better control of the disease was obtained by treating in mid-July than in mid-August, although flower production in the following season was impaired. [ABSTRACT FROM AUTHOR]

In a recent paper by D. R. Bellwood and C. P. Meyer (‘Searching for heat in a marine biodiversity hotspot’, Journal of Biogeography, 2009, 36, 569–576), the authors had two evident objectives: (1) to disprove the theory that the geographical origins of reef organisms could be determined by locating concentrations of endemic species, and (2) to emphasize that the high diversity of the Coral Triangle was due to an accumulation of species from outside that area. With regard to the first point, no such theory had previously been proposed to my knowledge. Second, the accumulation theory was promoted without consideration of the facts supporting the centre of origin hypothesis, except to dismiss it by saying that it had its origin in pre-continental drift ideas. This short response outlines the properties and evidence for the operation of centres of origin in this region. [ABSTRACT FROM AUTHOR]

The NEWS is a track and trigger risk score designed to identify deteriorating patients with a high risk of death/unintended intensive care admission within 24 h of those vital signs being taken [[4]]. He is indeed correct that the National Early Warning Score (NEWS) was much better at predicting 24-h mortality in the Kovacs et al. [[3]] study on emergency surgical admissions (c-statistic 0.89), than 30-day mortality following emergency bowel surgery in our paper (c-statistic 0.71). [Extracted from the article]

In a recent paper by M. J. Cavalcanti and V. Gallo, ‘Panbiogeographical analysis of distribution patterns in hagfishes (Craniata: Myxinidae)’ ( Journal of Biogeography, 2008, 35, 1258–1268), the authors studied the biogeography of an ancient fish family (Myxinidae) in the hope that the contemporary distributions of the species would reveal their past history and that of the ocean basins where they reside. In order to accomplish this task, there are several criteria that should have been met: (1) the ages of the taxa utilized (species) would have to be old enough to reflect the history of the areas where they are found, (2) the identification of the species as listed in the databases would have to be accurate, (3) the geographical locations indicated on the figures would have to be consistent with the statements in the text, and (4) the significance of the vicariant patterns would have to depend on evidence pertaining to the ages of such patterns. Unfortunately, it appears that none of these conditions has been met. It seems apparent that faith in an antiquated method of analysis led to neglect of the necessary steps in the analysis. This leaves little justification for publication of the paper, except to show that hagfishes are very widely distributed. [ABSTRACT FROM AUTHOR]

Summary: Pre‐operative risk stratification is a key part of the care pathway for emergency bowel surgery, as it facilitates the identification of high‐risk patients. Several novel risk scores have recently been published that are designed to identify patients who are frail or significantly unwell. They can also be calculated pre‐operatively from routinely collected clinical data. This study aimed to investigate the ability of these scores to predict 30‐day mortality after emergency bowel surgery. A single centre cohort study was performed using our local data from the National Emergency Laparotomy Audit database. Further data were extracted from electronic hospital records (n = 1508). The National Early Warning Score, Laboratory Decision Tree Early Warning Score and Hospital Frailty Risk Score were then calculated. The most abnormal National or Laboratory Decision Tree Early Warning Score in the 24 or 72 h before surgery was used in analysis. Individual scores were reasonable predictors of mortality (c‐statistic 0.699–0.740) but all were poorly calibrated. A National Early Warning Score ≥ 4 was associated with a high overall mortality rate (> 10%). A logistic regression model was developed using age, National Early Warning Score, Laboratory Decision Tree Early Warning Score and Hospital Frailty Risk Score as predictor variables, and its performance compared with other established risk models. The model demonstrated good discrimination and calibration (c‐statistic 0.827) but was marginally outperformed by the National Emergency Laparotomy Audit score (c‐statistic 0.861). All other models compared performed less well (c‐statistics 0.734–0.808). Pre‐operative patient vital signs, blood tests and markers of frailty can be used to accurately predict the risk of 30‐day mortality after emergency bowel surgery. [ABSTRACT FROM AUTHOR]

The development of metastasis is the most significant cause of death for both canine and human patients with osteosarcoma (OS). Ezrin has been associated with tumour progression and metastasis in human, canine and murine OS. Ezrin activation is dynamically regulated by protein kinase C (PKC) during metastatic progression in human and murine OS. To include the dog in the development of therapeutics that target ezrin biology, we characterized four new canine OS cell lines and confirmed the relationship between PKC and ezrin in these cells. Three of four cell lines formed tumours in mice that were histologically consistent with OS. All cell lines were markedly aneuploid and expressed ezrin and PKC. Finally, both ezrin phosphorylation and cell migration were inhibited using a PKC inhibitor. These data suggest that an association between PKC-mediated activation of ezrin and the metastatic phenotype in canine OS cells. [ABSTRACT FROM AUTHOR]

Aims: Adenosine causes vasoconstriction of afferent arterioles of the mouse kidney through activation of adenosine A1 receptors and Gi-mediated stimulation of phospholipase C. In the present study, we further explored the signalling pathways by which adenosine causes arteriolar vasoconstriction. Methods and results: Adenosine (10−7 m) significantly increased the intracellular calcium concentration in mouse isolated afferent arterioles measured by fura-2 fluorescence. Pre-treatment with thapsigargin (2 μm) blocked the vasoconstrictor action of adenosine (10−7 m) indicating that release of calcium from the sarcoplasmic reticulum (SR), stimulated presumably by IP3, is involved in the adenosine contraction mechanism of the afferent arteriole. In agreement with this notion is the observation that 2 aminoethoxydiphenyl borate (100 μm) blocked the adenosine-induced constriction whereas the protein kinase C inhibitor calphostin C had no effect. The calcium-activated chloride channel inhibitor IAA-94 (30 μm) inhibited the adenosine-mediated constriction. Patch clamp experiments showed that adenosine treatment induced a depolarizing current in preglomerular smooth muscle cells which was abolished by IAA-94. Furthermore, the vasoconstriction caused by adenosine was significantly inhibited by 5 μm nifedipine (control 8.3 ± 0.2 μm, ado 3.6 ± 0.6 μm, ado + nifedipine 6.8 ± 0.2 μm) suggesting involvement of voltage-dependent calcium channels. Conclusion: We conclude that adenosine mediates vasoconstriction of afferent arterioles through an increase in intracellular calcium concentration resulting from release of calcium from the SR followed by activation of Ca2+-activated chloride channels leading to depolarization and influx of calcium through voltage-dependent calcium channels. [ABSTRACT FROM AUTHOR]

In the present study we have investigated whether the presence of a second renin gene exerts an overriding influence on plasma renin such that mice with two renin genes have consistently higher renin levels than mice with only one renin gene. Plasma renin was determined as the rate of angiotensin I generation using a radioimmunoassay (RIA) kit with (plasma renin concentration, PRC) or without (plasma renin activity, PRA) the addition of purified rat angiotensinogen as substrate. In male 129SvJ, DBA/2 and Swiss Webster mice, strains possessing both Ren-1 and Ren-2, PRC (ng Ang I mL−1 h−1) averaged 178 ± 36, 563 ± 57 and 550 ± 43 while PRA was 2.9 ± 0.5, 3.6 ± 0.8 and 7.8 ± 1.2. In male C57BL/6, C3H and BALB/c mice that express only Ren-1, PRC averaged 426 ± 133, 917 ± 105 and 315 ± 72, and PRA was 3.4 ± 1.0, 6.9 ± 1.7 and 4.5 ± 1.2. In the two renin gene A1AR−/− mice compared with the one renin gene A1AR+/+, PRC averaged 538 ± 321 and 415 ± 159 while PRA averaged 3.2 ± 1.1 and 4.4 ± 1.4 ng Ang I mL−1 h−1. Aldosterone levels showed no significant differences between one renin (C57BL/6, C3H and BALB/c) and two renin (129SvJ, DBA/2 and Swiss Webster) gene mice. Furthermore, by quantitative real-time polymerase chain reaction (RT-PCR) we found no correlation between the number of renin genes and whole kidney renin mRNA levels from one and two renin gene mice. Our data show that baseline plasma renin is not systematically higher in mice with two renin genes than in one renin gene mice. Thus, the presence of a second renin gene does not seem to be a major determinant of differences in PRC between different mouse strains. [ABSTRACT FROM AUTHOR]

By crossing aquaporin 1 (AQP1)−/− and adenosine 1 receptor (A1AR)−/− mice, we generated an animal model that combines a proximal tubular absorption defect with absence of tubuloglomerular feedback (TGF) regulation of glomerular filtration rate (GFR) . The aim of studies in these animals was to determine whether a TGF-induced reduction of GFR is a prerequisite for preventing potentially fatal fluid losses. In contrast to AQP1 deficient mice, AQP1/A1AR−/− mice were found to have a normal GFR. TGF responses were abolished in these animals, in contrast to AQP1−/− mice in which TGF responses of single nephron glomerular filtration rate (SNGFR) were left-shifted. Proximal tubule fluid absorption in AQP1/A1AR−/− mice was reduced to levels previously reported for AQP1−/− mice. However, SNGFR was significantly higher in AQP1/A1AR−/− than AQP1−/− mice (10.6 ± 0.8 nL min−1 vs. 5.9 ± 0.7 nL min−1). As a consequence of the normal GFR and the reduced proximal reabsorption distal fluid delivery was markedly higher in the double knockout compared with normal or AQP1−/− mice (5.5 ± 0.5 nL min−1 vs. 2.35 ± 0.3 nL min−1 in AQP1−/−). Despite the approximate doubling of distal fluid and Cl delivery, AQP1/A1AR−/− mice have a normal salt excretion, normal arterial blood pressure, and only a small increase in plasma renin concentration. The ability to compensate for proximal tubule malabsorption without a TGF-induced reduction of GFR attests to a remarkable adaptability of distal tubule transport mechanisms. [ABSTRACT FROM AUTHOR]

McDonald KJ, McMillan MA, Rodger RSC, Junor BJR, Geddes CC, Briggs JD, Jardine AG. Persistent dipstick haematuria following renal transplantation. Clin Transplant 2004: 18: 321–326. © Blackwell Munksgaard, 2004 Despite widespread testing for dipstick haematuria following renal transplantation, there are no published series describing the prevalence and possible causes of this complication in an adult population. A cross-sectional study of 640 renal transplant recipients under review at our follow-up clinic was performed. Persistent haematuria was defined as a minimum of 1+ of blood on urinalysis stick testing detected at not fewer than 75% of clinic visits since its onset, or since the start of routine testing, present over a period of at least 4 weeks. The prevalence of persistent dipstick haematuria was 13.3%. Median serum creatinine was higher in patients with persistent haematuria but age, gender and length of time since transplantation were not significantly different. Potential explanations for persistent haematuria in 21 of 85 affected patients were chronic infection, ureteric stent without chronic infection, regular or intermittent self-catheterization, persistent menstrual bleeding, anticoagulant therapy, graft calculus, and allograft renal cell carcinoma. Recurrent or de novo glomerular disease was confirmed by graft biopsy in 10 of 85 patients. Among the 41 recipients whose original cause of renal failure was IgA nephropathy (IgAN), the prevalence of persistent haematuria was 31.7% compared with 12% in the remaining patients (relative risk 2.6, 95% CI: 1.6–4.3). Persistent haematuria in IgAN patients was not associated with gender, age or time since transplantation. After 29 months of follow-up, 20% of patients with haematuria had progressed to graft failure or death compared with 11.6% of the unaffected group (p = 0.029). However, despite the association with earlier graft failure, haematuria did not predict this endpoint independently of renal function. [ABSTRACT FROM AUTHOR]

The article presents information on a study which described the manufacture of ready-to-eat breakfast cereals by mixing corn meal with ascorbic acid and sucrose or lowbush blueberry concentrate and twin-screw extruded. The use of blueberry juice concentrate as a natural colorant in breakfast cereal is detailed. It identifies the effect of extrusion and ascorbic acid fortification on anthocyanins.

Fruit anthocyanins provide color and health benefits, thus cereals containing these pigments could be used as functional foods. White corn meal with 10% sucrose was twin-screw extruded with either corn syrup, lowbush blueberry concentrate, or Concord grape-juice concentrate. Extrusion reduced anthocyanins, but there was no change due to storage at room temperature for 3 mo. Polymeric color was higher in the blueberry cereal. The grape cereal was lighter and less red than the blueberry product. Bulk density was highest in the corn-syrup cereal. Overall acceptability was higher for the syrup and grape cereals. Sweetness and flavor acceptability were correlated with overall liking. [ABSTRACT FROM AUTHOR]

The author discusses role of opioids in the treatment of chronic pain. Topics discussed include lack of understanding about opioid abuse potential and the risk of addiction in healthcare settings, efficacy of long-term opioid use in the treatment of chronic pain, and development and use of non-opioid pain medications for pain management.