Developing simulation games to advance public health nursing competence in baccalaureate education.

We describe the development of an innovative baccalaureate nursing education strategy for public health nursing. Virtual simulation pedagogy is known to be effective for acute care nursing practice while less known for public health nursing. Three Canadian nursing schools, the Canadian Association of Schools of Nursing (CASN), and the Canadian Alliance of Nurse Educators using Simulation (CAN-Sim) partnered to develop three public health nursing virtual simulation games. Learners work through unfolding population health scenarios, simulating public health nursing practice focused on entry level public health nursing competencies. Each game fosters clinical reasoning and collaborative, community decision-making to respond to population health issues during community assessment, evidence-informed health promotion planning, and evaluation processes. A companion guide was developed to support best practices in implementing virtual simulation and promote optimum student learning using the public health nursing games.

A realist review of the home care literature and its blind spots.

RATIONALE, AIMS AND OBJECTIVES: There is a large body of literature from all over the world that describes, analyzes, or evaluates home care models and interventions. The present article aims to identify the practical lessons that can be gained from a systematic examination of that literature. METHOD: We conducted a three-step sequential search process from which 113 documents were selected. That corpus was then narratively analysed according to a realist review approach. RESULTS: A first level of observation is that there are multiple blind spots in the existing literature on home care. The definition and delimitation of what constitutes home care services is generally under-discussed. In the same way, the composition of the basket of care provided and its fit with the need of recipients is under-addressed. Finally, the literature relies heavily on RCTs whose practical contribution to decisions or policy is disputable. At a second level, our analysis suggests that three mechanisms (system integration, case management and relational continuity) are core characteristics of home care models' effectiveness. CONCLUSION: We conclude by providing advice for supporting the design and implementation of stronger home care delivery systems. Our analysis suggests that doing so implies a series of sequential steps: identify what system-level goals the model should achieve and which populations it should serve; identify what type of services are likely to achieve those goals in order to establish a basket of services; and finally, identify the best ways and specific means to effectively and efficiently provide those services. Those same steps can also support ex-post evaluations of existing home care systems.

Opening the doors for school health-An exploration of public health nurses' capacities to engage in comprehensive school health programs.

OBJECTIVES: Public health nurses (PHNs) have a significant role in engaging the voice and actions of school communities in promoting the health of children and youth. School nursing was one of the early 20th century public health nursing foci and specialties in Canada, however over several decades, there has been a gap in actualizing PHNs' full potential in schools. At the same time, intersectoral and interdisciplinary comprehensive school health (CSH) models have emerged as exemplars of partnerships between schools and communities to advance health promotion and ultimately chronic disease prevention with school populations (Pan-Canadian Joint Consortium for School Health, ; World Health Organization, ). DESIGN AND MEASUREMENT: Using a participatory action research methodology we explored the role of PHNs in CSH, drawing on the concept of engagement in intersectoral healthy school teams. RESULTS AND CONCLUSIONS: The three themes that emerged from the data analysis were: facilitators of public health nursing engagement, barriers to public health nursing engagement, and the influences of community context on engagement. Overall, findings indicate that the PHN role in CSH must be developed and supported so that PHNs remain a vital link between school health communities, programs, and policies in the promotion of health.

Chemical synthesis and characterization of two α4/7-conotoxins.

α-Conotoxins are small disulfide-constrained peptides that act as potent and selective antagonists on specific subtypes of nicotinic acetylcholine receptors (nAChRs). We previously cloned two α-conotoxins, Mr1.1 from the molluscivorous Conus marmoreus and Lp1.4 from the vermivorous Conus leopardus. Both of them have the typical 4/7-type framework of the subfamily of α-conotoxins that act on neuronal nAChRs. In this work, we chemically synthesized these two toxins and characterized their functional properties. The synthetic Mr1.1 could primarily inhibit acetylcholine (ACh)-evoked currents reversibly in the oocyte-expressed rat α7 nAChR, whereas Lp1.4 was an unexpected specific blocker of the mouse fetal muscle α1ß1γδ receptor. Although their inhibition affinities were relatively low, their unique receptor recognition profiles make them valuable tools for toxin-receptor interaction studies. Mr1.1 could also suppress the inflammatory response to pain in vivo, suggesting that it should be further investigated with respect to its molecular role in analgesia and its mechanism or therapeutic target for the treatment of pain.

Characterization of a novel alpha4/4-conotoxin, Qc1.2, from vermivorous Conus quercinus.

As part of continuing studies of the identification of gene organization and cloning of novel alpha-conotoxins, the first alpha4/4-conotoxin identified in a vermivorous Conus species, designated Qc1.2, was originally obtained by cDNA and genomic DNA cloning from Conus quercinus collected in the South China Sea. The predicted mature toxin of Qc1.2 contains 14 amino acid residues with two disulfide bonds (I-III, II-IV connectivity) in a native globular configuration. The mature peptide of Qc1.2 is supposed to contain an N-terminal post-translationally processed pyroglutamate residue and a free carboxyl C-terminus. This peptide was chemically synthesized and refolded for further characterization of its functional properties. The synthetic Qc1.2 has two interconvertible conformations in aqueous solution, which may be due to the cis-trans isomerization of the two successive Pro residues in its first Cys loop. Using the Xenopus oocyte heterologous expression system, Qc1.2 was shown to selectively inhibit both rat neuronal alpha3beta2 and alpha3beta4 subtypes of nicotinic acetylcholine receptors with low potency. A block of about 63% and 37% of the ACh-evoked currents was observed, respectively, and the toxin dissociated rapidly from the receptors. Compared with other characterized alpha-conotoxin members, the unusual structural features in Qc1.2 that confer to its receptor recognition profile are addressed.

Engineering neuronal nicotinic acetylcholine receptors with functional sensitivity to alpha-bungarotoxin: a novel alpha3-knock-in mouse.

We report here the construction of a novel knock-in mouse expressing chimeric alpha3 nicotinic acetylcholine receptor (nAChR) subunits with pharmacological sensitivity to alpha-bungarotoxin (alphaBTX). Sensitivity was generated by substituting five amino acids in the loop C (beta9-beta10) region of the mouse alpha3 subunit with the corresponding residues from the alpha1 subunit of the muscle type receptor from Torpedo californica. To demonstrate the utility of the underlying concept, expressed alpha3[5] subunits were characterized in the superior cervical ganglia (SCG) of homozygous knock-in mice, where the synaptic architecture of postsynaptic alpha3-containing nAChR clusters could now, for the first time, be directly visualized and interrogated by live-staining with rhodamine-conjugated alphaBTX. Consistent with the postsynaptic localization of ganglionic nAChRs, the alphaBTX-labeled puncta colocalized with a marker for synaptic varicosities. Following in vivo deafferentation, these puncta persisted but with significant changes in intensity and distribution that varied with the length of the recovery period. Compound action potentials and excitatory postsynaptic potentials recorded from SCG of mice homozygous for alpha3[5] were abolished by 100 nmalphaBTX, even in an alpha7 null background, demonstrating that synaptic throughput in the SCG is completely dependent on the alpha3-subunit. In addition, we observed that the genetic background of various inbred and outbred mouse lines greatly affects the functional expression of alpha3[5]-nAChRs, suggesting a powerful new approach for exploring the molecular mechanisms underlying receptor assembly and trafficking. As alphaBTX-sensitive sequences can be readily introduced into other nicotinic receptor subunits normally insensitive to alphaBTX, the findings described here should be applicable to many other receptors.

alpha4/7-conotoxin Lp1.1 is a novel antagonist of neuronal nicotinic acetylcholine receptors.

Cone snails comprise approximately 700 species of venomous molluscs which have evolved the ability to generate multiple toxins with varied and exquisite selectivity. alpha-Conotoxin is a powerful tool for defining the composition and function of nicotinic acetylcholine receptors which play a crucial role in excitatory neurotransmission and are important targets for drugs and insecticides. An alpha4/7 conotoxin, Lp1.1, originally identified by cDNA and genomic DNA cloning from Conus leopardus, was found devoid of the highly conserved Pro residue in the first intercysteine loop. To further study this toxin, alpha-Lp1.1 was chemically synthesized and refolded into its globular disulfide isomer. The synthetic Lp1.1 induced seizure and paralysis on freshwater goldfish and selectively reversibly inhibited ACh-evoked currents in Xenopus oocytes expressing rat alpha3beta2 and alpha6alpha3beta2 nAChRs. Comparing the distinct primary structure with other functionally related alpha-conotoxins could indicate structural features in Lp1.1 that may be associated with its unique receptor recognition profile.

A novel pharmatope tag inserted into the beta4 subunit confers allosteric modulation to neuronal nicotinic receptors.

alpha-Bungarotoxin, the classic nicotinic antagonist, has high specificity for muscle type alpha1 subunits in nicotinic acetylcholine receptors. In this study, we show that an 11-amino-acid pharmatope sequence, containing residues important for alpha-bungarotoxin binding to alpha1, confers functional alpha-bungarotoxin sensitivity when strategically placed into a neuronal non-alpha subunit, normally insensitive to this toxin. Remarkably, the mechanism of toxin inhibition is allosteric, not competitive as with neuromuscular nicotinic receptors. Our findings argue that alpha-bungarotoxin binding to the pharmatope, inserted at a subunit-subunit interface diametrically distinct from the agonist binding site, interferes with subunit interface movements critical for receptor activation. Our results, taken together with the structural similarities between nicotinic and GABAA receptors, suggest that this allosteric mechanism is conserved in the Cys-loop ion channel family. Furthermore, as a general strategy, the engineering of allosteric inhibitory sites through pharmatope tagging offers a powerful new tool for the study of membrane proteins.

Screening for and analysis of methylation differences using methylation-sensitive single-strand conformation analysis.

Methylation-sensitive single-strand conformation analysis (MS-SSCA) is a method of screening for methylation changes at CpG sites in a region of DNA. After bisulfite modification, the region of interest is amplified using primers specific for bisulfite-modified sequences. The amplified products are denatured and run on a nondenaturing polyacrylamide gel. The sequence differences caused by methylation lead to the formation of different secondary structures (conformers) with different mobilities. MS-SSCA is a convenient and rapid method for screening large numbers of samples for methylation. Individual bands can readily be isolated and sequenced allowing more detailed analysis of methylation changes. In this article, we present a protocol for MS-SSCA and outline strategies for the design of primers for amplifying bisulfite-modified DNA sequences.