Stimulus-secretion coupling in gland cells

The work described in this thesis is divided into three main sections- The first section concerns the role of calcium in the control of fluid secretion. When cockroach salivary glands are bathed in calcium-free medium the basal rate of fluid secretion increases from about 1nl/min to about 10nl/min; maintained dopamine stimulation elicits a further rise in secretory rate which gradually declines. Evidence is presented which suggests that magnesium is unable to substitute for calcium in this system. When calcium is returned to the bathing solution after a period of calcium deprivation there is a transient increase in secretory rate. The calcium ionophore A23187 also elicits an increase in secretory rate which is maintained in the presence of extracellular calcium but declines in calcium-free medium. Stimulation of the glands in certain conditions which inhibit the secretory response leads to some kind of calcium-dependent active state in the secretory cells which can outlast the interaction of the agonist with its receptors. The conclusion drawn from this section of the work is that stimulus-secretion coupling in this gland involves a calcium-dependent second messenger system.The second section is concerned with investigating the existence and possible location of a cellular store of calcium involved in stimulus-secretion coupling. The fluorescent compound chlorotetracycline (CTC) enters the cells of the cockroach salivary gland. The acinar peripheral cells and non-secretory duct cells become preferentially labelled by CTC. Microscopic examination of the intracellular distribution of CTC indicates that this compound labels the highly folded apical plasma membranes of the peripheral cells and the deep infolds of the basal membranes of the non-secretory duct cells. Lanthanum blocks the entry of CTC into all of the gland cells and in this condition the CTC labels the basal surfaces of the acini and ducts. The results of this investigation support the idea that CTC labels calcium ions in the vicinity of plasma membranes. A comparison was made between glands in which the calcium stores had been depleted by dopamine stimulation in calcium-free medium, prior to CTC labelling, and glands which had not been stimulated prior to labelling. No apparent reduction in the labelling of stimulated , and glands compared to unstimulated glands was noted.The third section of this work is concerned with the role of cyclic AMP in the control of fluid secretion. Exposure of the glands to exogenous cyclic AMP causes an increase in fluid secretion; maximal responses to cyclic AMP virtually match the maximal responses of the same glands to dopamine. The secretory response to maintained exogenous cyclic AMP declines in calciumfree medium. The calcium-dependence of the active state which arises in the cells during stimulation in conditions preventing fluid secretion cannot be bypassed by application of exogenous cyclic AMP. Forskolin, which reputedly stimulates adenyl cyclase, does not consistently stimulate fluid secretion. The adenyl cyclase inhibitor MDL 12,330A blocks the secretory responses to dopamine, calcium readmission and A23187. Application of the phosphodiesterase inhibitor IBMX causes an increase in fluid secretion,which declines in calcium-free medium and is blocked by MDL 12,330A. It is concluded from this section that an increase in intracellular cyclic AMP is an important step in stimulussecretion coupling in the cockroach salivary gland. Preliminary experiments to determine intracellular cyclic AMP concentration using radio-immunoassay have been carried out.In conclusion a model is presented of stimulus-secretion coupling in the cockroach salivary gland, in which calcium and cyclic AMP act as synarchic second messengers regulating fluid secretion

Impact of Culturally Tailored Shared Medical Appointments on Diabetes Self-Care Ability and Knowledge in African Americans

Background: Type 2 diabetes mellitus (T2DM) continues to disproportionately affect African Americans, significantly impacting morbidity and mortality. Research suggests that addressing barriers that stem from socioeconomic circumstances, systemic inequalities, biological factors, and cultural factors may positively influence biometric indicators of health and diabetes control. Objective: The aim of this study was to evaluate a diabetes shared medical appointment (SMA) model program that has been culturally tailored to address the unique social determinants of health barriers faced by an inner city African American population in Norfolk, Virginia. Methods: A pilot study using a within-group pretest–posttest design was conducted. Information was collected from self-report surveys that included the Modified Michigan Diabetes Knowledge Test, the Diabetes Self-Efficacy Scale, and researcher generated surveys before and after a single-session three-hour SMA program. Key Results: The program increased perceived diabetes self-care confidence and perceived overall diabetes knowledge levels. Increases in knowledge scores were seen but not statistically significant. Participants reported high levels of satisfaction with the program model. Discussion: Findings indicate that this model is an effective and engaging method of improving self-care ability and diabetes disease management knowledge among African Americans. Addressing unique circumstances and barriers experienced by this population may be more effective than usual traditional care approaches

Making a Global Impact One Vaccine at a Time

(First paragraph) Did you know that, worldwide, almost one third of deaths among children under age 5 can be prevented by vaccines? It\u27s stunning to think that one child dies every 20 seconds from an immunization-preventable disease. That equates to 12 lives that could be saved in the time it takes to read this brief article

Interweaving in hybrid methodologies

The paper will consider instances of the interweaving of theory and practice within drawing research, in order to suggest potential approaches to the development of hybrid methodologies in fine art practice-led research. The paper is written from the position of two current supervisors and creative research collaborators: Deborah Harty and Phil Sawdon (aka humhyphenhum from 2007), who historically were supervisee/supervisor. The paper will make reference to Harty's experience as a Ph.D. researcher undertaking practice-led research within a fine art context (completed 2010) and supervised by Sawdon. A discussion of Harty's hybrid methodology: action theoria, will provide an instance of the interweaving of theory and practice. Action theoria incorporates the cyclical and iterative process of action research – intention; action; review – with a process of theoria – the dialogue of both practice and theory's relationship to a given subject matter. Following this, the paper will discuss the interweaving of action theoria into humhyphenhum's collaborative research methodology: meaningful play. This interwoven methodology evolved during collaborative practice-led research projects from 2005 to the present. The paper will make reference to several of humhyphenhum's projects as a means to identify the interweaving of theory and practice within collaborative research. As current supervisors (2015), the paper will conclude with a discussion of how reflection on these experiences has informed our position as supervisors. We will consider, for example, how this has impacted on our ability, as individual supervisors, to offer insights into the interweaving of theory and practice, without defaulting to the position of compelling our supervisees to adopt our methodology

Protocol for a gender-sensitised weight loss and healthy living programme for overweight and obese men delivered in Australian football league settings (Aussie-FIT): A feasibility and pilot randomised controlled trial

Introduction: Overweight and obesity are highly prevalent among Australian men. Professional sports settings can act as a powerful 'hook' to engage men in weight loss programmes; the Football Fans in Training programme delivered in professional UK soccer clubs was successful and cost-effective in helping men lose weight. The Australian Football League (AFL) is a potentially attractive setting to engage men in a weight loss programme. We aim to develop, pilot and evaluate the feasibility of a weight loss intervention for overweight/obese middle-aged men, delivered in AFL settings, to promote weight loss and healthier lifestyles and determine its suitability for a future randomised control trial. Methods and analysis: 120 overweight/obese male fans will complete baseline physical and psychological health measures and objective measures of physical activity (PA), weight, waist size and blood pressure prior to randomisation into the intervention or waitlist comparison group. The intervention group will receive 12 weekly 90 min workshops incorporating PA, nutrition education, behaviour change techniques and principles of effective motivation. Four community coaches will be trained to deliver Aussie-FIT at two AFL clubs in Western Australia. Measurements will be repeated in both groups at 3 months (post-intervention) and 6 months (follow-up). Outcomes will include programme uptake, attendance, changes in lifestyle and weight variables to inform power calculations for a future definitive trial, fidelity of programme delivery, acceptability, satisfaction with the programme and perceptions of effectiveness. We will also determine trial feasibility and potential to gather cost-effectiveness data. Ethics and dissemination: Ethics approval was granted by Curtin University's Human Research Ethics Committee (HREC2017-0458). Results: will be disseminated via peer-reviewed publications, conference presentations and reports. A multicomponent dissemination strategy will include targeted translation and stakeholder engagement events to establish strategies for sustainability and policy change. Trial registration number: ACTRN12617000515392; Pre-results

A global perspective of advanced practice nursing research:a review of systematic reviews protocol

INTRODUCTION: In 2020, the World Health Organization called for the expansion and greater recognition of all nursing roles, including advanced practice nurses (APNs), to better meet patient care needs. As defined by the International Council of Nurses (ICN), the two most common APN roles include nurse practitioners (NPs) and clinical nurse specialists (CNSs). They help ensure care to communities as well as patients and families with acute, chronic or complex conditions. Moreover, APNs support providers to deliver high quality care and improve access to services. Currently, there is much variability in the use of advanced practice nursing roles globally. A clearer understanding of the roles that are in place across the globe, and how they are being used will support greater role harmonization, and inform global priorities for advanced practice nursing education, research, and policy reform. OBJECTIVE: To identify current gaps in advanced practice nursing research globally. MATERIALS AND METHODS: This review of systematic reviews will provide a description of the current state of the research, including gaps, on advanced practice nursing globally. We will include reviews that examine APNs, NPs or CNSs using recognized role definitions. We will search the CINAHL, EMBASE, Global Health, HealthStar, PubMed, Medline, Cochrane Library Database of Systematic Reviews and Controlled Trials Register, Database of Abstracts of Reviews of Effects, Joanna Briggs Institute, and Web of Science electronic databases for reviews published from January 2011 onwards, with no restrictions on jurisdiction or language. We will search the grey literature and hand search the reference lists of all relevant reviews to identify additional studies. We will extract country, patient, provider, health system, educational, and policy/scope of practice data. We will assess the quality of each included review using the CASP criteria, and summarize their findings. This review of systematic reviews protocol was developed following the PRISMA-P recommendations. PROSPERO REGISTRATION NUMBER: CRD42021278532

Evaluation of (−)-epicatechin metabolites as recovery biomarker of dietary flavan-3-ol intake

Abstract: Data from dietary intervention studies suggest that intake of (−)-epicatechin mediates beneficial vascular effects in humans. However, population-based investigations are required to evaluate associations between habitual intake and health and these studies rely on accurate estimates of intake, which nutritional biomarkers can provide. Here, we evaluate a series of structurally related (−)-epicatechin metabolites (SREM), particularly (−)-epicatechin-3′-glucuronide, (−)-epicatechin-3′-sulfate and 3′-O-methyl-(−)-epicatechin-5-sulfate (SREMB), as flavan-3-ol and (−)-epicatechin intake. SREMB in urine proved to be a specific indicator of (−)-epicatechin intake, showing also a strong correlation with the amount of (−)-epicatechin ingested (R2: 0.86 (95% CI 0.8l; 0.92). The median recovery of (−)-epicatechin as SREMB in 24 h urine was 10% (IQR 7–13%) and we found SREMB in the majority of participants of EPIC Norfolk (83% of 24,341) with a mean concentration of 2.4 ± 3.2 µmol/L. Our results show that SREMB are suitable as biomarker of (−)-epicatechin intake. According to evaluation criteria from IARC and the Institute of Medicine, the results obtained support use of SREMB as a recovery biomarker to estimate actual intake of (−)-epicatechin

Big data and data repurposing – using existing data to answer new questions in vascular dementia research

Introduction: Traditional approaches to clinical research have, as yet, failed to provide effective treatments for vascular dementia (VaD). Novel approaches to collation and synthesis of data may allow for time and cost efficient hypothesis generating and testing. These approaches may have particular utility in helping us understand and treat a complex condition such as VaD. Methods: We present an overview of new uses for existing data to progress VaD research. The overview is the result of consultation with various stakeholders, focused literature review and learning from the group’s experience of successful approaches to data repurposing. In particular, we benefitted from the expert discussion and input of delegates at the 9th International Congress on Vascular Dementia (Ljubljana, 16-18th October 2015). Results: We agreed on key areas that could be of relevance to VaD research: systematic review of existing studies; individual patient level analyses of existing trials and cohorts and linking electronic health record data to other datasets. We illustrated each theme with a case-study of an existing project that has utilised this approach. Conclusions: There are many opportunities for the VaD research community to make better use of existing data. The volume of potentially available data is increasing and the opportunities for using these resources to progress the VaD research agenda are exciting. Of course, these approaches come with inherent limitations and biases, as bigger datasets are not necessarily better datasets and maintaining rigour and critical analysis will be key to optimising data use