Nurses' experience of managing adults living with multimorbidity: A qualitative study.

BACKGROUND: The number of adults living with two or more chronic conditions is increasing worldwide. Adults living with multimorbidity have complex physical, psychosocial and self-management care needs. AIM: This study aimed to describe Australian nurses' experience of care provision for adults living with multimorbidity, their perceived education needs and future opportunities for nurses in the management of multimorbidity. DESIGN: Qualitative exploratory. METHODS: Nurses providing care to adults living with multimorbidity in any setting were invited to take part in a semi-structured interview in August 2020. Twenty-four registered nurses took part in a semi-structured telephone interview. RESULTS: Three main themes were developed: (1) The care of adults living with multimorbidity requires skilled collaborative and holistic care; (2) nurses' practice in multimorbidity care is evolving; and (3) nurses value education and training in multimorbidity care. CONCLUSION: Nurses recognize the challenge and the need for change in the system to support them to respond to the increasing demands they face. IMPACT: The complexity and prevalence of multimorbidity creates challenges for a healthcare system configured to treat individual disease. Nurses are key in providing care for this population, but little is known about nurses' experiences and perceptions of their role. Nurses believe a person-centred approach is important to address the complex needs of adults living with multimorbidity. Nurses described their role as evolving in response to the growing demand for quality care and believed inter-professional approaches achieve the best outcomes for adults living with multimorbidity. The research has relevance for all healthcare providers seeking to provide effective care for adults living with multimorbidity. Understanding how best to equip and support the workforce to meet the issues and demands of managing the care of adults living with multimorbidity has the potential to improve patient outcomes. PATIENT OR PUBLIC CONTRIBUTION: There was no patient or public contribution. The study only concerned the providers of the service.

Water Chemistry, Exposure Routes, and Metal Forms Determine the Bioaccumulation Dynamics of Silver (Ionic and Nanoparticulate) in Daphnia magna.

Treatment wetlands utilize various physical and biological processes to reduce levels of organic contaminants, metals, bacteria, and suspended solids. Silver nanoparticles (AgNPs) are one type of contaminant that can enter treatment wetlands and impact the overall treatment efficacy. Grazing by filter-feeding zooplankton, such as Daphnia magna, is critical to treatment wetland functioning; but the effects of AgNPs on zooplankton are not fully understood, especially at environmentally relevant concentrations. We characterized the bioaccumulation kinetics of dissolved and nanoparticulate (citrate-coated) 109 Ag in D. magna exposed to environmentally relevant 109 Ag concentrations (i.e., 0.2-23 nmol L-1 Ag) using a stable isotope as a tracer of Ag. Both aqueous and nanoparticulate forms of 109 Ag were bioavailable to D. magna after exposure. Water chemistry affected 109 Ag influx from 109 AgNP but not from 109 AgNO3 . Silver retention was greater for citrate-coated 109 AgNP than dissolved 109 Ag, indicating a greater potential for bioaccumulation from nanoparticulate Ag. Feeding inhibition was observed at higher dietary 109 Ag concentrations, which could lead to reduced treatment wetland performance. Our results illustrate the importance of using environmentally relevant concentrations and media compositions when predicting Ag bioaccumulation and provide insight into potential effects on filter feeders critical to the function of treatment wetlands. Environ Toxicol Chem 2022;41:726-738. © 2021 SETAC.

Simulation to educate healthcare providers working within residential age care settings: A scoping review.

BACKGROUND: Simulation is used widely in health education to develop healthcare providers' knowledge and skills. The use of simulation however, as an educational strategy among aged care worker is not well understood. OBJECTIVES: This review sought to describe studies where simulation is used to educate healthcare providers working within aged care settings; describe the method and structure used in simulations in residential aged care; the key learning outcomes for the participants in this setting; and identify any gaps in the current literature to illuminate future research opportunities. DESIGN: The review follows the Joanna Briggs Institute Scoping Review methodology and utilises the PRISMA-ScR Checklist. Searches of CINAHL Complete, PubMed and Scopus databases were completed using the search terms "Simulation" AND "training" AND "Aged Care" OR "Elderly" OR "Older People". Inclusion criteria were peer-reviewed, English, full-text articles published from database inception to July 2018. RESULTS: Twenty studies were included in this review. Studies differed in their methodology, sample size and participants and their findings varied significantly. Fourteen studies originated from the United States of America, five from Canada, and one from Taiwan. Studies were published between 1977 and July 2018. Clinical topics used in simulation were aggression and violence; dementia; aging; death and dying; range of motion exercises; person-centred care; sepsis; and dressing residents. Simulation types were role play, simulated patients, and mannequins. Debrief was described in less than a third of studies. Just over half of the studies evaluated participant outcomes. DISCUSSION/CONCLUSION: This study demonstrated a large paucity of evidence utilising simulation for training within aged care settings. It highlights the need for future research in this area where simulation could be utilised to meet the unique learning needs of nurses working in aged care.

Reframing evidence-based practice curricula to facilitate engagement in nursing students.

Evidence-based practice underscores a modern approach to nursing to ensure delivery of safe, up-to-date and person-centred care in the evolving clinical environment. While most entry-to-practice nursing courses incorporate elements of evidence-based research curricula, nursing students commonly struggle to see the relevance of research in their training. This study sought to understand nursing students' satisfaction and perspectives on research after an undergraduate research subject was redesigned to make overt the connection between research and professional nursing practice. Satisfaction significantly improved on routinely collected satisfaction surveys over a one-year period (mean increase 0.57, 95% CI 0.40-0.77, P < 0.001; medium effect size, 0.64). Open-ended questions elicited five themes: change to preconceived ideas of research to something accessible and useful; clear link between research and clinical and professional nursing practice; comments on subject format and scaffolded learning; increased skills in effective searching and extracting evidence; and improvements for the future. Student satisfaction increased when the connection between research learning and professional practice was made overt in a core research subject. This approach, along with scaffolded activities to increase confidence, had a marked positive impact on student's attitude and understanding of the utility of evidence-based practice and confidence in scrutinising practice in the clinical environment.

Competency assessment tools: An exploration of the pedagogical issues facing competency assessment for nurses in the clinical environment.

Competency assessment is a paradigm that is common in the healthcare environment and this being particularly true within the nursing profession. Demonstration of competence is necessary to meet the requirements of healthcare organisations and is a mandated requirement of nurses by the Nursing and Midwifery Board of Australia. Within the nursing education sector, one approach to determine competence, is through the use of competency assessment tools. Despite widespread use of competency assessment tools there remains ongoing concerns relating to the efficacy of competency assessment tools as a mean to demonstrate 'competency' amongst enrolled and registered nurses in the clinical environment. The authors of this paper ascertain that competency assessment tools run a serious risk of being nothing more than a 'quick-fix' means of assessment to demonstrate 'nursing competence' required for key performance indicators and clinical governance and that will provide evidence for accreditation standards. Based on this premise, the authors, provide an alternative approach to the use of competency assessment tools that moves away from a 'tick-box' approach to a 'patient-centred' competency model. This approach increases the reliability and validity of competency assessments, allows for the recognition of the knowledge, skills and experience of individual nurses, offers a more satisfying and rewarding approach to demonstrating 'competency' for nurses and finally, demonstrates 'real-life' competency.

Toxicity of dissolved Cu, Zn, Ni and Cd to developing embryos of the blue mussel (Mytilus trossolus) and the protective effect of dissolved organic carbon.

Marine water quality criteria for metals are largely driven by the extremely sensitive embryo-larval toxicity of Mytilus sp. Here we assess the toxicity of four dissolved metals (Cu, Zn, Ni, Cd) in the mussel Mytilus trossolus, at various salinity levels while also examining the modifying effects of dissolved organic carbon (DOC) on metal toxicity. In 48 h embryo development tests in natural seawater, measured EC50 values were 6.9-9.6 microg L(-1) (95% C.I.=5.5-10.8 microg L(-1)) for Cu, 99 microg L(-1) (86-101) for Zn, 150 microg L(-1) (73-156) for Ni, and 502 microg L(-1) (364-847) for Cd. A salinity threshold of >20 ppt (approximately 60% full strength seawater) was required for normal control development. Salinity in the 60-100% range did not alter Cu toxicity. Experimental addition of dissolved organic carbon (DOC) from three sources reduced Cu toxicity; for example the EC50 of embryos developing in seawater with 20 mg C L(-1) was 39 microg Cu L(-1) (35.2-47.2) a 4-fold increase in Cu EC50. The protective effects of DOC were influenced by their distinct physicochemical properties. Protection appears to be related to higher fulvic acid and lower humic acid content as operationally defined by fluorescence spectroscopy. The fact that DOC from freshwater sources provides protection against Cu toxicity in seawater suggests that extrapolation from freshwater toxicity testing may be possible for saltwater criteria development, including development of a saltwater Biotic Ligand Model for prediction of Cu toxicity.

Physiological and biochemical effects of lithium in rainbow trout.

The physiological responses of juvenile rainbow trout (Oncorhynchus mykiss) to lithium (as LiCl) in moderately hard freshwater (CaCO(3) = 120-140 ppm, Na(+) = approximately 0.6 mM) were studied. The study employed a 15-day step-up exposure regime; 66 microg/L Li for the first 9 days and 528 microg/L for the next 6 days. The concentrations of plasma ions, apolipoprotein AI, total cholesterol, and fatty acids, as well as metabolic enzyme citrate synthase (CS) and Na(+),K(+)-ATPase activities in the gill were measured. Li affected fish by exacerbated diffusive Na(+) losses at the gills in the beginning of exposure and a decrease of branchial CS activity. Detrimental effects were shown in fish exposed to 528 microg Li/L. These included a reduction of gill Na(+),K(+)-ATPase activity, possibly related to observed lower concentrations of free fatty acids and cholesterol in gill tissue.

Interactions of waterborne and dietary cadmium on the expression of calcium transporters in the gills of rainbow trout: influence of dietary calcium supplementation.

Recent studies have shown that dietary Ca(2+) supplementation strongly inhibits uptake of Ca(2+) and Cd at the fish gill. To better understand the influence of dietary Ca(2+) on branchial Ca(2+) transport, we examined the expression of two trout gill calcium transporters during waterborne and dietary Cd exposure, at two different levels of dietary Ca(2+). Quantitative polymerase chain reaction (PCR) was used to monitor epithelial calcium channel (ECaC) and sodium-calcium exchange (NCX) mRNA levels following 7-28 days of exposure to these treatments. In brief, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to control, 3 microg/L waterborne Cd, 500 mg/kg dietary Cd, or a combined 3 microg/L waterborne plus 500 mg/kg dietary Cd exposure, supplemented with either 20 mg/g or 60 mg/g dietary calcium (Ca(2+)). Two-way analysis of variance was used to discern the main effects of Cd exposure and dietary Ca(2+) supplementation on ECaC and NCX mRNA levels. We found that dietary Ca(2+) supplementation decreased significantly ECaC mRNA expression on days 14 and 21. In comparison, NCX mRNA levels were not influenced by dietary Ca(2+) supplementation, but rather were significantly inhibited in the combined waterborne and dietary Cd exposure on day 7 alone. Statistical analysis found no interactive effects between Cd exposure and dietary Ca(2+) exposure at any time point, except for day 28. This study provides evidence of the importance of nutritional status on the transcriptional regulation of ion transport at the fish gill. We discuss the importance of diet and nutritional status to the development of new regulatory approaches, such as the biotic ligand model, which currently do not account for the significance of diet on metal bioavailability in aquatic organisms.

Comparative toxicity of nanoparticulate ZnO, bulk ZnO, and ZnCl2 to a freshwater microalga (Pseudokirchneriella subcapitata): the importance of particle solubility.

Metal oxide nanoparticles are finding increasing application in various commercial products, leading to concerns for their environmental fate and potential toxicity. It is generally assumed that nanoparticles will persist as small particles in aquatic systems and that their bioavailability could be significantly greater than that of larger particles. The current study using nanoparticulate ZnO (ca. 30 nm) has shown that this is not always so. Particle characterization using transmission electron microscopy and dynamic light scattering techniques showed that particle aggregation is significant in a freshwater system, resulting in flocs ranging from several hundred nanometers to several microns. Chemical investigations using equilibrium dialysis demonstrated rapid dissolution of ZnO nanoparticles in a freshwater medium (pH 7.6), with a saturation solubility in the milligram per liter range, similar to that of bulk ZnO. Toxicity experiments using the freshwater alga Pseudokirchneriella subcapitata revealed comparable toxicity for nanoparticulate ZnO, bulk ZnO, and ZnCl2, with a 72-h IC50 value near 60 microg Zn/ L, attributable solely to dissolved zinc. Care therefore needs to be taken in toxicity testing in ascribing toxicity to nanoparticles per se when the effects may be related, at least in part, to simple solubility.

The effect of pH on the uptake and toxicity of copper and zinc in a tropical freshwater alga (Chlorella sp.).

Copper and zinc toxicity to the freshwater alga Chlorella sp. was determined at a range of pH values (5.5-8.0) in a synthetic softwater (hardness 40-48 mg CaCO(3)/L). The effects of the metals on algal growth (cell division) rate were determined after 48-h exposure at pH 5.5, 6.0, 6.5, 7.0, 7.5, and 8.0. The toxicity of both metals was pH dependent. As pH decreased from 8.0 to 5.5, the copper concentration required to inhibit the algal growth rate by 50% (IC50) increased from 1.0 to 19 microg/L. For zinc, the IC50 increased from 52 to 2,700 microg/L over the same pH range. Changes in solution speciation alone did not explain the increased toxicity observed as the pH increased. Modelled Cu(2+) and Zn(2+) concentrations decreased with increasing pH, whereas toxicity was observed to increase. Measurements of extracellular (cell-bound) metal concentrations support the biotic ligand model (BLM) theory of competition between protons (H(+)) and metals for binding sites at the algal cell surface. Higher extracellular metal concentrations were observed at high pH, indicating reduced competition. Independent of pH, both extracellular and intracellular copper were directly related to growth inhibition in Chlorella sp., whereas zinc toxicity was related to cell-bound zinc only. These findings suggest that the algal cell surface may be considered as the biotic ligand in further development of a chronic BLM with microalgae. Conditional binding constants (log K) were determined experimentally (using measured intracellular metal concentrations) and theoretically (using concentration-response curves) for copper and zinc for Chlorella sp. at selected pH values. Excellent agreement was found indicating the possibility of using concentration-response data to estimate conditional metal-cell binding constants.

Toward a biotic ligand model for freshwater green algae: surface-bound and internal copper are better predictors of toxicity than free Cu2+-ion activity when pH is varied.

The freshwater green microalgae Chlorella sp. and Pseudokirchneriella subcapitata (P. subcapitata) were chronically (48 and 72 h, respectively) exposed to copper at various pH levels, i.e., pH 6-7.5 and pH 5.9-8.5, respectively. Concentrations resulting in 50% inhibition of exponential growth rate (EC50) were determined as dissolved Cu, estimated chemical activity of the free Cu2+ ion (as pCu = - log{Cu2+ activity as molarity}), and as external (surface-bound) Cu and internal Cu in the algal cells. With increasing pH, EC50dissolved decreased from 30 to 1.1 microg of Cu L(-1) for Chlorella sp. and from 46 to 18 microg of Cu L(-1) for P. subcapitata. The pH effect on copper toxicity was even more obvious when expressed as Cu2+ activity. The EC50pCu increased on average 1.4 pCu unit per pH unit for Chlorella sp. and 1.1 pCu unit per pH unit for P. subcapitata, thus indicating a marked increase of Cu2+ toxicity at higher pH (more than 1 order of magnitude per pH unit). In contrast, it was found that EC50 values expressed as surface bound or external copper (EC50external) and as internal copper (EC50internal) did not vary substantially when pH was increased. External Cu was operationally defined as the Cu fraction removable from the algal cell by short-term contact with ethylenediaminetetraacetic acid; internal copper was defined as the nonremovable fraction. For Chlorella sp. the EC50external varied between 5 and 10 fg of Cu/ cell (factor of 2 difference) and the EC50internal between 25 and 40 fg of Cu/cell (factor of 1.6 difference). For P. subcapitata the EC50external varied between 10 and 28 fg of Cu/cell (factor of 2.8 difference) and the EC50internal between 42 and 71 fg of Cu/cell (factor of 1.7 difference). Because the observed variation in EC50external and EC50internal is much less than the variation in EC50Cu2+, it is concluded that both external and internal copper are better predictors of copper toxicity than Cu2+ when pH is varied. From the perspective of toxicity modeling, this observation is the first step toward considering the use of the cell surface as the algal biotic ligand for Cu in a similar way as fish gills fulfill this role in the biotic ligand model for predicting metal toxicity to fish species.

Calcium/cadmium interactions at uptake surfaces in rainbow trout: waterborne versus dietary routes of exposure.

Juvenile rainbow trout (Oncorhynchus mykiss) were exposed to control, 3 microg/L waterborne Cd, or 500 mg/kg dietary Cd in combination with either a control (20 mg/g Ca2+ as CaCO3) or elevated (60 mg/g Ca2+) Ca2+ diet for 28 d. No mortality or growth effects were observed in response to either route of Cd exposure, although fish fed Ca2+-supplemented diets exhibited minor reductions in growth within the first few days of feeding. Waterborne and dietary Cd resulted in significant Cd accumulation in most tissues, with dietary uptake being far in excess of waterborne under the exposure conditions used. The order of Cd accumulation strongly reflected the exposure pathway, being gill and kidney > liver > gut > carcass (waterborne Cd); gut > kidney > liver > gill > carcass > bone (dietary Cd). On a whole-body basis, the net retention of Cd from the diet was < 1%, indicating that the gut wall forms an important protective barrier reducing Cd accumulation into internal tissues. Dietary Ca2+ supplementation reduced short-term whole-body uptake rates of waterborne Ca2+ and Cd by >50% and resulted in much lower chronic accumulation of Cd (via the water and diet) in target tissues. Results suggest that Ca2+ and Cd share common pathway(s)/transport mechanism(s) in the gill and gut and that increased gastrointestinal Ca2+ uptake likely caused downregulation of branchial and gastrointestinal Ca2+ and therefore Cd uptake pathways. Because nutrient metals other than Ca2+ may also influence Cd (and other metal) uptake, new regulatory approaches to metal toxicity (e.g., biotic ligand model) require understanding of the influence of dietary status on metal accumulation.

Development of multispecies algal bioassays using flow cytometry.

Multispecies algal bioassays, suitable for assessing copper toxicity, were developed with three marine (Micromonas pusilla, Phaeodactylum tricornutum, and Heterocapsa niei) and three freshwater (Microcystis aeruginosa, Pseudokirchneriella subcapitata, and Trachelomonas sp.) microalgae. Flow cytometry was used to separate and count algal signals based on pigment fluorescence and cell size. Species were mixed together on the basis of equivalent surface areas to avoid the confounding effect on toxicity of increased biomass for metal binding. Under control conditions (no added copper), M. pusilla growth was inhibited in the presence of the other marine microalgae compared to single-species tests, while the opposite was true (i.e., growth stimulation) for M. aeruginosa and P. subcapitata in freshwater mixtures. Competition for nutrients, including CO2, and algal exudate production may account for these effects. Interactions between microalgal species also had a significant effect on copper toxicity to some species. In freshwater multispecies bioassays, the toxicity of copper to Trachelomonas sp. was greater in the presence of other species, with copper concentrations required to inhibit growth (cell division) rate by 50% (72-h [IC50]) decreasing from 9.8 to 2.8 microg Cu/L in single- and multispecies bioassays, respectively. In contrast, in marine multispecies bioassays, copper toxicity to the marine diatom P. tricornutum was reduced compared to single-species bioassays, with an increase in the 72-h IC50 value from 13 to 24 microg Cu/L. This reduction in copper toxicity was not explained by differences in the copper complexing capacity in solution (as a result of exudate production) because labile copper, measured by anodic stripping voltammetry, was similar for P. tricornutum alone and in the mixture. These results demonstrate that single-species bioassays may over- or underestimate metal toxicity in natural waters.

Toxicity of metal mixtures to a tropical freshwater alga (Chlorella sp): the effect of interactions between copper, cadmium, and zinc on metal cell binding and uptake.

The individual and combined effects of copper, cadmium, and zinc on the cell division rate of the tropical freshwater alga Chlorella sp. were determined over 48 to 72 h. Metal mixtures were prepared based on multiples of their single-metal median effective concentration (EC50) values, i.e., toxic units (TU) using a triangular mixture design with five toxicant levels (0, 0.75, 1.0, 1.25, and 1.5 TU). Single-metal EC50 values after a 72-h exposure were 0.11, 0.85, and 1.4 microM for copper, cadmium, and zinc, respectively. Significant interactions were observed for all metal combinations after 48 and 72 h. An equitoxic mixture of Cu + Cd was more than concentration additive (synergistic) to the growth of Chlorella sp., while combinations of Cu + Zn, Cd + Zn, and Cu + Cd + Zn were all less than concentration additive or were antagonistic. To determine the effect of each metal on the uptake of the other, extracellular (membrane-bound) and intracellular metal concentrations, both alone and in mixtures, were compared. The increased growth inhibition observed for mixtures of Cu + Cd was due to higher concentrations of cell-bound and intracellular copper in the presence of cadmium compared with copper alone (i.e., cadmium-enhanced copper uptake). In contrast, both extra- and intracellular cadmium concentrations were reduced in the presence of copper. In mixtures of Cu + Zn, copper also inhibited the binding and cellular uptake of zinc, which resulted in decreased toxicity. Zinc had no appreciable effect on the uptake of copper by Chlorella sp. Our results suggest that all three metals share some common uptake and transport sites on Chlorella cells and that copper out competes both cadmium and zinc for cell binding. Determination of metal cell distribution coefficients (K(d)) confirmed that K(d) values for cadmium and zinc in single-metal exposures decreased in the presence of copper.

Effect of initial cell density on the bioavailability and toxicity of copper in microalgal bioassays.

Algal toxicity tests based on growth inhibition over 72 h have been extensively used to assess the toxicity of contaminants in natural waters. However, these laboratory tests use high cell densities compared to those found in aquatic systems in order to obtain a measurable algal response. The high cell densities and test duration can result in changes in chemical speciation, bioavailability, and toxicity of contaminants throughout the test. With the recent application of flow cytometry to ecotoxicology, it is now possible to use lower initial cell densities to minimize chemical speciation changes. The speciation and toxicity of copper in static bioassays with the tropical freshwater alga Chlorella sp. and the temperate species Selenastrum capricornutum (Pseudokirchneriella subcapitata) were investigated at a range of initial cell densities (10(2)-10(5) cells/ml). Copper toxicity decreased with increasing initial cell density. Copper concentrations required to inhibit growth (cell division) rate by 50% (72-h median effective concentration [EC50]) increased from 4.6 to 16 microg/L for Chlorella sp. and from 6.6 to 17 microg/L for S. capricornutum as the initial cell density increased from 10(2) to 10(5) cells/ml. Measurements of anodic stripping voltammetry-labile, extracellular, and intracellular copper confirmed that at higher initial cell densities, less copper was bound to the cells, resulting in less copper uptake and lower toxicity. Chemical measurements indicated that reduced copper toxicity was due primarily to depletion of dissolved copper in solution, with solution speciation changes due to algal exudates and pH playing a minor role. These findings suggest that standard static laboratory bioassays using 10(4) to 10(5) algal cells/ml may seriously underestimate metal toxicity in natural waters.

Applications of flow cytometry to ecotoxicity testing using microalgae.

Flow cytometry is a rapid method for the quantitative measurement of light scattering and fluorescent properties of cells. Although this technique has been widely applied to biomedical and environmental studies, its potential as a tool in ecotoxicological studies has not yet been fully exploited. This article describes the application of flow cytometry to the development of bioassays with marine and freshwater algae for assessing the bioavailability of contaminants in waters and sediments.