Investigation of the quality and health literacy demand of online information on pelvic floor exercises to reduce stress urinary incontinence

BACKGROUND

Many women are embarrassed to discuss pelvic floor exercises with health professionals during pregnancy; instead they search the internet for information on pelvic floor exercises.

AIMS

This project investigated the quality and health literacy demand in terms of readability, understandability and actionability of information available on the internet relating to pelvic floor exercises.

MATERIALS AND METHODS

An analysis was conducted on 150 websites and 43 videos obtained from three consecutive Google searches relating to pelvic floor exercises. Websites were assessed for Health on the Net certification. Readability was assessed using a readability calculator, and understandability/actionability of website and video information was assessed using the Patient Education Materials Assessment Tool (PEMAT) for Print or Audiovisual Materials.

RESULTS

Less than one-third (24%) of the websites were certified for quality. The median readability score for the websites was grade 9 and the websites and videos both rated highly for understandability and actionability. The median understandability score for the website information was 87%, and the median actionability score was 71%. The median understandability score of the video information was 95.5% and the median actionability score was 100%. The understandability and actionability of video information was also significantly greater than that for website information (P < 0.01).

CONCLUSION

Clinicians could consider directing patients to video-based resources when advising online pelvic floor exercise resources for women during pregnancy, especially those with lower health literacy.

The Australian health workforce: Disproportionate shortfalls in small rural towns

INTRODUCTION

The distribution of health care workers differs greatly across Australia, which is likely to impact health delivery.

OBJECTIVE

To examine demographic and workplace setting factors of doctors, nurses and midwives, and allied health professionals across Modified Monash Model (MMM) regions and identify factors associated with shortfalls in the health care workforce.

DESIGN

Descriptive cross-sectional analysis. The study included all health professionals who were registered with the Australian Health Practitioner Regulation Agency in 2021, and who were working in Australia in their registered profession. The study examined number of registrations and full-timed equivalent (FTE) registrations per MMM region classification, adjusted for population. Associated variables included age, gender, origin of qualification, Indigenous status and participation in the private or public (including government, non-government organisation and not-for-profit organisations) sectors.

FINDINGS

Data were available for 31 221 general practitioners, 77 277 other doctors, 366 696 nurses and midwives, and 195 218 allied health professionals. The lowest FTE per 1000 people was seen in MM5 regions for general practitioners, other doctors, nurses and midwives, and allied health professionals. Demographic factors were mostly consistent across MM regions, although MM5 regions had a higher percentage of nurses and midwives and allied health professionals aged 55 and over. In the private sector, FTE per 1000 people was lowest in MM5-7 regions. In the public sector, FTE per 1000 people was lowest in MM5 regions.

DISCUSSION

A disproportionate shortfall of health workers was seen in MM5 regions. This shortfall appears to be primarily due to low FTE per capita of private sector workers compared with MM1-4 regions and a low FTE per capita of public sector workers compared with MM6-7 regions.

CONCLUSION

In Australia, small rural towns have the lowest number of health care workers per capita which is likely to lead to poor health outcomes for those regions.

Individuals' perceptions and expectations of nutrition care provided by doctors in Australia: A focus group study

BACKGROUND AND OBJECTIVES

Doctors are well placed to facilitate nutrition care to support dietary improvements due, in part, to their regular contact with their patients. Limited literature exists which explores the perspective of patients regarding the nutrition care provided by medical professionals across the continuum of care. This article explores the perspective of patients regarding perceptions of nutrition advice and care received from doctors and expectations of this care, including key skills and attributes the patients perceive as important.

METHOD

Six online focus groups were conducted with Australian service users (n=32).

RESULTS

Framework analysis identified four key themes: perceptions of doctors' role in nutrition care, expectations and experiences; the importance of individualised care; barriers and enablers to nutrition care; and topics, skills and attributes perceived as important in nutrition care.

DISCUSSION

Patients have a desire for individualised and collaborative nutrition care but experienced systemic barriers in practice.

A comparison of rural and regional work locations and speciality choices between graduates from the University of Wollongong and all Australian medical schools using the Medical Schools Outcomes Database

INTRODUCTION

The shortfall in medical workers in rural and remote Australia has led to health discrepancies in these regions. The University of Wollongong's medical program was designed to encourage graduates to work in these regions to address this shortfall.

OBJECTIVE

To compare rural and regional locations of work and choices of speciality between University of Wollongong's graduates and graduates from all Australian universities.

DESIGN

We conducted a longitudinal analysis on data available from the Medical Schools Outcome database, with graduate exit surveys linked to registrations of location and speciality. Rural and remote locations were identified as MM2-7 regions using the Modified Monash Model. In total, 716 graduates from the University of Wollongong and 26 915 graduates from all Australian medical schools completed the MSOD exit survey in 2010-2021 and registered with the Australian Health Practitioner Regulation Agency in 2022. The main outcome was the relative likelihood (relative risk) of cohorts working in rural and regional areas and of cohorts choosing general practice as their speciality.

FINDINGS

University of Wollongong's medical graduates were 1.51 times or 51% more likely to work in regional or rural areas (RR 1.51, 95% CI 1.34 to 1.71, p < 0.0001). Respondents who were 10 or more years post graduation were 1.57 times or 57% more likely to specialise in general practice than all other Australian medical graduates (RR 1.57 95% CI: 1.40 to 1.79, p < 0.0001).

DISCUSSION

The University of Wollongong's medical school is producing graduates to meet Australia's rural health workforce needs. This may be due to a higher intake of rural students, and a higher percentage of students taking rural placements.

CONCLUSIONS

Rural health workforce needs can be addressed through rural-focussed education strategies.

The INHABIT (synergIstic effect of aNtHocyAnin and proBIoTics in) Inflammatory Bowel Disease trial: a study protocol for a double-blind, randomised, controlled, multi-arm trial

Ulcerative Colitis (UC), a type of Inflammatory Bowel Disease (IBD), is a chronic, relapsing gastrointestinal condition with increasing global prevalence. The gut microbiome profile of people living with UC differs from healthy controls and this may play a role in the pathogenesis and clinical management of UC. Probiotics have been shown to induce remission in UC; however, their impact on the gut microbiome and inflammation is less clear. Anthocyanins, a flavonoid subclass, have shown anti-inflammatory and microbiota-modulating properties; however, this evidence is largely preclinical. To explore the combined effect and clinical significance of anthocyanins and a multi-strain probiotic, a 3-month randomised controlled trial will be conducted in 100 adults with UC. Participants will be randomly assigned to one of four groups: anthocyanins (blackcurrant powder) + placebo probiotic, probiotic + placebo fruit powder, anthocyanin + probiotic, or double placebo. The primary outcome is a clinically significant change in the health-related quality-of-life measured with the Inflammatory Bowel Disease Questionnaire-32. Secondary outcomes include shotgun metagenomic sequencing of the faecal microbiota, faecal calprotectin, symptom severity, and mood and cognitive tests. This research will identify the role of adjuvant anti-inflammatory dietary treatments in adults with UC and elucidate the relationship between the gut microbiome and inflammatory biomarkers in this disease, to help identify targeted individualised microbial therapies. ANZCTR registration ACTRN12623000630617.

An automated protocol for assessing career rurality outcomes of Australian health professionals using retrospective data

INTRODUCTION

Addressing the imbalance of the health workforce between metropolitan and rural areas requires a clear understanding of trends in choices of work location of health care staff.

OBJECTIVE

Here, we provide an automated and highly reproducible protocol to examine the location of health care workers over multiple years using medical graduates as a case study.

DESIGN

Data linkage cohort study. The study cohort examined was University of Wollongong Medical graduates from 2010 to 2021 who were registered to practice in Australia. The main outcome measure was graduate location of practice in Modified Monash regsions MM1 or MM2-7 across multiple postgraduate years. This protocol used R Markdown.

FINDINGS

An automated and reproducible protocol was used to analyse choices of work location for the University of Wollongong's medical graduates. Over 90% of graduates were registered with AHPRA. Around 25%-30% of graduates were found to work in MM2-7 regions across their careers, exceeding the national average.

DISCUSSION

The protocol presented allows for a fast and reproducible analysis of work location by region for health care workers. This will allow comparisons of outcomes between universities or health professions.

Cranberry, but not D-mannose and ibuprofen, prevents against uropathogenic Escherichia coli-induced cell damage and cell death in MDCK cells

Introduction

The main function of the urinary tract is to form an impermeable barrier against urinary solutes and bacteria. However, this barrier can be compromised by urinary tract infections, most commonly caused by uropathogenic Escherichia coli (UPEC). This can result in damage to the epithelial barrier, leading to decreased epithelial thickness, loss of tight junctions, loss of epithelial integrity, and apoptosis. Due to the rise in antimicrobial resistance, there is worldwide interest in exploring non-antibiotic agents as alternative therapy.

Methods

Using the Madin-Darby canine kidney (MDCK) cell line, a widely accepted epithelial cell model for the urinary tract, and the UPEC strain UTI89, this paper aimed to investigate the impact of UPEC on cell integrity, permeability, and barrier functions, and determine whether cranberry, D-mannose and ibuprofen could counteract the effects induced by UPEC. Furthermore, the study examined the protective potential of these agents against UPEC-induced increase in reactive oxygen species (ROS) production and programmed death-ligand 1 (PD-L1) expression.

Results

The results demonstrated that UTI89 caused a marked reduction in cell viability and monolayer integrity. Cranberry (3 mg/mL) was protective against these changes. In addition, cranberry exhibited protective effects against UPEC-induced damage to cell barrier integrity, escalation of oxidative stress, and UPEC/TNFα-triggered PD-L1 expression. However, no effect was observed for D-mannose and ibuprofen in alleviating UPEC-induced cell damage and changes in ROS and PD-L1 levels.

Conclusion

Overall, cranberry, but not D-mannose or ibuprofen, has a protective influence against UPEC associated damage in urinary epithelial cells.

Effective Treatments of UTI—Is Intravesical Therapy the Future?

Urinary tract infection (UTI) afflicts millions of patients globally each year. While the majority of UTIs are successfully treated with orally administered antibiotics, the impact of oral antibiotics on the host microbiota is under close research scrutiny and the potential for dysbiosis is a cause for concern. Optimal treatment of UTI relies upon the selection of an agent which displays appropriate pharmacokinetic-pharmacodynamic (PK-PD) properties that will deliver appropriately high concentrations in the urinary tract after oral administration. Alternatively, high local concentrations of antibiotic at the urothelial surface can be achieved by direct instillation into the urinary tract. For antibiotics with the appropriate physicochemical properties, this can be of critical importance in cases for which an intracellular urothelial bacterial reservoir is suspected. In this review, we summarise the underpinning biopharmaceutical barriers to effective treatment of UTI and provide an overview of the evidence for the deployment of the intravesical administration route for antibiotics.

Attitudes, work roles and barriers to nutrition care - Interviews with Australian and UK-based medical doctors

BACKGROUND

Poor diet is implicated in multiple chronic diseases. While doctors may be well-placed to facilitate nutrition care, nutrition remains a low priority in medical education internationally. Consensus is required on nutrition competencies as a benchmark for education with a regulatory framework to ensure implementation. The aim of this qualitative study was to explore work roles, attitudes, barriers, and enablers in the delivery of nutrition care amongst a cohort of Australian and UK doctors.

METHODOLOGY

Semi-structured interviews were conducted with primary care doctors/GPs (n=14) and medical specialists (n=8) based in Australia and the United Kingdom to explore work roles, attitudes, barriers and enablers in the delivery of nutrition care.

RESULTS

Framework analysis identified five key themes: 1) Knowledge and skills in nutrition to support medical nutrition care, 2) The delivery of nutrition education, 3) Multidisciplinary and interdisciplinary care, 4) Systemic barriers and facilitators to care and, 5) The need for a paradigm shift. Participants acknowledged nutrition as an important component of medical care but recognised they are currently ill-equipped to support such care, identifying limitations to the systems supporting integrated care. Participants identified that nutrition sits within both a health promotion and medical/treatment model, but they currently work only within the latter.

CONCLUSION

Participants highlighted a lack of knowledge and training around nutrition, without which change is not possible. Efforts to improve the nutrition capacity of the medical workforce must be matched by increased investments in primary prevention, including nutrition - a paradigm shift from the medical model. This article is protected by copyright. All rights reserved.

Virulence Mechanisms of Common Uropathogens and Their Intracellular Localisation within Urothelial Cells

A recurrent urinary tract infection (UTI) is a common debilitating condition whereby uropathogens are able to survive within the urinary tract. In this study, we aimed to determine if the common uropathogens Escherichia coli, Enterococcus faecalis, and Group B Streptococcus possessed virulence mechanisms that enable the invasion of urothelial cells. Urothelial cells were isolated from women with detrusor overactivity and recurrent UTIs; the intracellular localisation of the uropathogens was determined by confocal microscopy. Uropathogens were also isolated from women with acute UTIs and their intracellular localisation and virulence mechanisms were examined (yeast agglutination, biofilm formation, and haemolysis). Fluorescent staining and imaging of urothelial cells isolated from women with refractory detrusor overactivity and recurrent UTIs demonstrated that all three uropathogens were capable of intracellular colonisation. Similarly, the bacterial isolates from women with acute UTIs were also seen to intracellularly localise using an in vitro model. All Enterococcus and Streptococcus isolates possessed a haemolytic capacity and displayed a strong biofilm formation whilst yeast cell agglutination was unique to Escherichia coli. The expression of virulence mechanisms by these uropathogenic species was observed to correlate with successful urothelial cell invasion. Invasion into the bladder urothelium was seen to be a common characteristic of uropathogens, suggesting that bacterial reservoirs within the bladder contribute to the incidence of recurrent UTIs.

Urinary Tract Infection in Overactive Bladder: An Update on Pathophysiological Mechanisms

Overactive bladder (OAB) is a clinical syndrome defined by urinary urgency, increased daytime urinary frequency and/or nocturia, with or without urinary incontinence, that affects approximately 11% of the western population. OAB is accepted as an idiopathic disorder, and is charactersied clinically in the absence of other organic diseases, including urinary tract infection. Despite this, a growing body of research provides evidence that a significant proportion of OAB patients have active bladder infection. This review discusses the key findings of recent laboratory and clinical studies, providing insight into the relationship between urinary tract infection, bladder inflammation, and the pathophysiology of OAB. We summarise an array of clinical studies that find OAB patients are significantly more likely than control patients to have pathogenic bacteria in their urine and increased bladder inflammation. This review reveals the complex nature of OAB, and highlights key laboratory studies that have begun to unravel how urinary tract infection and bladder inflammation can induce urinary urgency and urinary frequency. The evidence presented in this review supports the concept that urinary tract infection may be an underappreciated contributor to the pathophysiology of some OAB patients.

Protective Effect of Purinergic P2X7 Receptor Inhibition on Acrolein-Induced Urothelial Cell Damage

Patients undergoing chemotherapy with cyclophosphamide experience cystitis due to excretion of a toxic metabolite, acrolein. Cystitis, an inflammation of the bladder, is associated with damage to the integrity of the urothelial barrier. The purinergic P2X7 receptor (P2X7R) is increasingly recognized for its role in inflammation and cell death. P2X7R is expressed abundantly on the bladder urothelium. The aim of this study was to investigate the role of P2X7R in acrolein-induced inflammatory damage in primary cultured porcine bladder urothelial cells. Confluent urothelial cells in culture were treated with acrolein to induce damage; also, with the P2X7R selective antagonist, A804598. Cell viability assay, immunocytochemistry, and trans-epithelial electrical resistance (TEER) studies were carried out to investigate the effect of treatments on urothelial cell function. Acrolein induced a significant reduction in urothelial cell viability, which was protected by the presence of A804598 (10 µM). The urothelial barrier function, indicated by TEER values, was also significantly reduced by acrolein, whereas pre-incubation with P2X7R antagonist significantly protected the urothelial cell barrier from acrolein-induced TEER reduction. The structure of urothelial cell tight junctions was similarly impacted by acrolein treatment, showing the fragmentation of zona occludens-1 (ZO-1) immunoreactivity. Pre-treatment of cells with A804598 countered against the actions of acrolein and maintained ZO-1 expression level and cell structure. The damaging effect of acrolein on urothelial cells integrity could be impaired by inhibition of P2X7R, therefore P2X7R blockade may be a possible therapy in patients with bladder cystitis caused by cyclophosphamide treatment.

Stakeholder Engagement in Competency Framework Development in Health Professions: A Systematic Review

Competency framework development in health professions has downstream implications for all relevant stakeholders, from the professionals themselves, to organisations, and most importantly end users of services. However, there is little guidance related to what stakeholders might be involved in the competency development process, and when. This review aimed to systematically review literature related to competency framework development methodology in health, to identify the breadth and purpose of key stakeholders commonly involved in the process. Studies were identified using five electronic databases (MEDLINE, PubMed, CINAHL, EMBASE, and ERIC) and a search of websites of organisations involved in curriculum or regulation using keywords related to competency frameworks. The total yield from all databases was 10,625 results, with 73 articles included in the final review. Most articles were from Australia (30%) and were conducted in the nursing (34%) profession. Unsurprisingly, practitioners (86%) and academics (75%) were typically engaged as stakeholders in competency framework development. While many competency frameworks were described as patient-focused, only 14 (19%) studies elected to include service users as stakeholders. Similarly, despite the multi-disciplinary focus described in some frameworks, only nine (12%) studies involved practitioners from other professions. Limiting the conceptualisation of competence to that determined by members of the profession itself may not provide the depth of insight required to capture the complexity of healthcare and address the needs of important stakeholder groups. Future methodology should attempt to engage a variety of relevant stakeholders such as external health professions and the community to match professional education to health service demands. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=128350.

P2X7 Receptor Blockade Protects Against Acrolein-Induced Bladder Damage: A Potential New Therapeutic Approach for the Treatment of Bladder Inflammatory Diseases

Inflammatory conditions of the urinary bladder have been shown to be associated with urothelial damage and loss of function. The purinergic P2X7 receptor has been implicated in several inflammatory conditions. The aim of this study was to investigate the role of the P2X7 receptor in acrolein-induced inflammatory damage using the porcine urinary bladder. For this purpose, an ex-vivo model of porcine urothelial damage induced by direct instillation of acrolein into the whole bladder lumen was used. To determine the role of the P2X7 receptor, the bladders were pre-incubated with a selective P2X7 receptor antagonist, A804598 (10 μM), for 1 h. The effects of the acrolein-induced urothelial damage on the bladder’s function were assessed by examining the bladder wall contractile response, structure changes, apoptosis, and oxidative stress in the bladder tissues. The acrolein treatment led to significant damage to the urothelium histology, tight junction expression, and contractile responses. Acrolein also induced apoptosis in the mucosa layer. All these acrolein-induced responses were attenuated by pre-treatment with the P2X7 receptor antagonist A804598. Acrolein also significantly induced DNA oxidation in the submucosal layer; however, the P2X7 receptor antagonism did not show any protective effect towards the acrolein-induced oxidative stress. These findings suggested that the P2X7 receptor is involved in the acrolein-induced damage to the urothelium; therefore, the P2X7 receptor antagonists may be a new therapeutic option for the treatment of bladder inflammation.

Autocrine regulation of wound healing by ATP release and P2Y2 receptor activation

AIMS

Application of exogenous nucleotides can modulate wound healing via the activation of purinergic receptors. However, evidence for the release of endogenous nucleotides and the subsequent activation of purinergic receptors in this process has not been well defined. Therefore, the current study aimed to investigate wound-mediated nucleotide release and autocrine purinergic signalling during HaCaT keratinocyte wound closure following scratch injury.

MAIN METHODS

An in vitro scratch wound apparatus was employed to study wound healing over 24-h in the presence of modulators of ATP release, P2 receptors and pathways downstream of P2 receptor activation.

KEY FINDINGS

Adenosine 5'-triphosphate (ATP) was released from scratched cells. The ectonucleotidase apyrase and pharmacological inhibition of the nucleotide release hemichannel, pannexin-1, decreased wound closure over time. The non-selective P2Y receptor antagonist suramin and the selective P2Y₂ receptor antagonist AR-C118925XX, but not other P2 antagonists, decreased wound closure. AR-C118925XX decreased wound closure in a concentration-dependent fashion. However, exogenous P2Y₂ receptor agonists, ATP or uridine 5'-triphosphate, did not enhance wound closure. PCR and immunoblotting confirmed P2Y₂ receptor expression in HaCaT cells. U73122, a phospholipase C antagonist, and 2-aminoethoxydiphenylborate, an inositol 1,4,5-trisphosphate receptor-sensitive Ca²⁺-release channel antagonist, decreased wound closure consistent with P2Y₂ receptor activation. Absence of extracellular or intracellular Ca²⁺ or inhibition of intracellular Ca²⁺-release also impaired wound closure.

SIGNIFICANCE

These data describe a novel autocrine signalling mechanism in which wound-mediated release of endogenous ATP in response to mechanical scratching of HaCaT cells activates P2Y₂ receptors to facilitate wound closure.

Factors Affecting Satisfaction with the Decision-Making Process and Decision Regret for Men with a New Diagnosis of Prostate Cancer

For men with newly diagnosed prostate cancer the decisions about treatment options are complex and difficult. The aim of this study was to investigate any association between the extent to which men wanted to be involved in the decision making process, their satisfaction with that process, and their levels of decision regret after treatment. The study population consisted of men diagnosed with prostate cancer at a regional center in Australia. Men (n = 324) were invited to complete a mail out survey which included demographic questions, the treatment chosen, and three validated tools: The Control Preference Scale to measure the degree of control assumed when making decisions about medical interventions; the Treatment Decision-Making Satisfaction Scale (TDM- SAT) to assess satisfaction with the treatment decision making process; and the Decision Regret Scale to assess the level of regret after treatment. The majority of the 151 respondents (47% response rate) expressed an active decision control preference. There was no correlation between age and the treatment chosen or the degree of control men exerted over the decision-making process. Men who preferred a passive role were less satisfied with the decision-making process than were those who took an active or collaborative approach. A strong inverse correlation was demonstrated between regret experienced and satisfaction with the decision-making process. In conclusion, for men newly diagnosed with prostate cancer, taking an active role in the treatment decision making process led to greater satisfaction with that process, which in turn reduced their chances of experiencing regret following treatment.

Bacterial colonization of bladder urothelial cells in women with refractory Detrusor Overactivity: the effects of antibiotic therapy

Bacterial infection may have a pathophysiological role in refractory Detrusor Overactivity (DO). The aim of this study was to observe any impact of antibiotic therapy upon bacterial colonization of urothelial cells, and to determine whether a relationship existed between colonization and symptom severity. Mid-stream urine samples were collected as part of a clinical trial of antibiotics in women with refractory DO. Wright stained urothelial cells were categorized according to the degree of bacterial colonization as; 'clear' (free of bacteria), or as associated with bacteria that were 'adjacent' to the cell or 'intracellular' at low or high density. The average percentages were compared with routine microbiology cultures, over the 26 week trial, and with patient clinical outcome measures of DO severity. In patients receiving placebo, 'high-density intracellular bacteria' significantly increased during urinary tract infection (P = 0.0008). In antibiotic patients, 'clear' cells were more prevalent. Amoxicillin & Clavulanic Acid significantly decreased bacterial colonization within urothelial cells, suggesting that these antibiotics possess the greatest intracellular efficacy. 'High-density intracellular bacteria' positively correlated with symptom severity, measured by leakage on pad test (P = 0.014), leaks per day (P = 0.004), and voids per day (P = 0.005). Thus, by decreasing high density intracellular bacteria, antibiotic treatment may improve the refractory DO condition.

Nutrition competencies for medicine: an integrative review and critical synthesis

OBJECTIVE

Globally, 11 million deaths are attributable to suboptimal diet annually, and nutrition care has been shown to improve health outcomes. While medically trained clinicians are well-placed to provide nutrition care, medical education remains insufficient to support clinicians to deliver nutrition advice as part of routine clinical practice. Competency standards provide a framework for workforce development and a vehicle for aligning health priorities with the values of a profession. Although, there remains an urgent need to establish consensus on nutrition competencies for medicine. The aim of this review is to provide a critical synthesis of published nutrition competencies for medicine internationally.

DESIGN

Integrative review.

DATA SOURCES

CINAHL, Medline, Embase, Scopus, Web of Science and Global Health were searched through April 2020.

ELIGIBILITY CRITERIA

We included published Nutrition Competency Frameworks. This search was complemented by handsearching reference lists of literature deemed relevant.

DATA EXTRACTION AND SYNTHESIS

Data were extracted into summary tables and this matrix was then used to identify common themes and to compare and analyse the literature. Miller's pyramid, the Knowledge to Action Cycle and the Dreyfus model of skill acquisition were also used to consider the results of this review.

RESULTS

Using a predetermined search strategy, 11 articles were identified. Five common themes were identified and include (1) clinical practice, (2) health promotion and disease prevention, (3) communication, (4) working as a team and (5) professional practice. This review also identified 25 nutrition competencies for medicine, the majority of which were knowledge-based.

CONCLUSIONS

This review recommends vertical integration of nutrition competencies into existing medical education based on key, cross-cutting themes and increased opportunities to engage in relevant, skill-based nutrition training.

Reference to nutrition in medical accreditation and curriculum guidance: a comparative analysis

Objective

Poor diet is a leading cause of death worldwide. Doctors are well placed to provide dietary advice, yet nutrition remains insufficiently integrated into medical education. Enforcement of curriculum or accreditation requirements such as nutrition requires relevant regulatory frameworks. The aim of this review was to identify nutrition content or requirements for nutrition education in accreditation standards or formal curriculum guidance for medical education internationally.

Design

Non-systematic comparative analysis.

Data sources

An internet search using the Google Search engine, the WHO Directory of Medical Schools and Foundation for Advancement of International Medical Education and Research Directory of Organizations that Recognise/Accredit Medical Schools was conducted through September 2020 to identify government and organisational reports as well as publications from regulatory and professional bodies relevant to medical education.

Eligibility criteria

Eligible publications included (A) accreditation standards, (B) competency standards or a framework, (C) curricula, and (D) assessment content.

Data extraction and synthesis

We stratified findings by country or region and both preregistration and postregistration education. Findings were synthesised based on the existence of nutrition content or requirements for nutrition education within systems used to guide medical education internationally.

Results

This review found that despite an emphasis on meeting the needs of the community and the demands of the labour market, only 44% of accreditation and curriculum guidance included nutrition. Nutrition remains inadequately represented in accreditation and curriculum guidance for medical education at all levels internationally. Accreditation standards provide a mandated framework for curricula and inclusion of nutrition in accreditation frameworks provides an incentive for the integration of nutrition into medical education.

Conclusions

This review is a call to action for the medical profession including government, health agencies and educational and accreditation entities. The inclusion of nutrition in medical education has appeared throughout medical education literature for more than five decades, yet without consensus standards there is little likelihood of uniform adoption.

Urinary cytokines in women with refractory detrusor overactivity: A longitudinal study of rotating antibiotic versus placebo treatment

Over 50% of women with detrusor overactivity (DO), who do not respond to therapy have been shown to have bacteriuria, which may stimulate the release of inflammatory cytokines than can enhance nerve signalling, leading to symptoms of urgency. This study made use of a consecutive series of urine samples collected from women with refractory DO, who participated in a clinical trial of rotating antibiotic therapy. The aim was to determine the effect of bacteriuria and antibiotic treatment on the levels of urinary cytokines, and to correlate the cytokine concentration with patient outcome measures relating to urgency or urge incontinence. The urinary cytokines chosen were IL-1α, IL-1 receptor antagonist, IL-4, IL-6, IL-8, IL-10, CXCL10 (IP-10), MCP-1 and TNF-α. The presence of bacteriuria stimulated a significant increase in the concentrations of IL-1α (P 0.0216), IL-1 receptor antagonist (P 0.0264), IL-6 (P 0.0003), IL-8 (P 0.0043) and CXCL-10 (P 0.009). Antibiotic treatment significantly attenuated the release of IL-1α (P 0.005), IL-6 (P 0.0027), IL-8 (P 0.0001), IL-10 (P 0.049), and CXCL-10 (P 0.042), i.e. the response to the presence of bacteria was less in the antibiotic treated patients. Across the 26 weeks of the trial, antibiotic treatment reduced the concentration of five of the nine cytokines measured (IL-1α, IL-6, IL-8, IL-10 and CXCL-10); this did not reach significance at every time point. In antibiotic treated patients, the urinary concentration of CXCL-10 correlated positively with four of the six measures of urgency. This study has shown that cytokines associated with activation of the innate immune system (e.g. cytokines chemotactic for or activators of macrophages and neutrophils) are reduced by antibiotic therapy in women with refractory DO. Antibiotic therapy is also associated with symptom improvement in these women, therefore the inflammatory response may have a role in the aetiology of refractory DO.

Effect of antibiotics on urine leakage in women with refractory detrusor overactivity: A phase IIb randomized trial

AIM

Because bacterial cystitis is common in women with refractory detrusor overactivity, the aim was to compare the efficacy of 6 weeks of rotating antibiotics versus placebo, in conjunction with an anticholinergic, in controlling the symptoms of urge incontinence.

METHODS

In a multicenter phase IIb double-blinded randomized placebo-controlled trial, women with urodynamically proven refractory detrusor overactivity were randomized in a 2:1 ratio of antibiotics versus placebo for 6 weeks, in addition to darifenacin for 6 months. Any woman with disabling cystitis symptoms was given appropriate antibiotics ("clinical override"). The primary outcome was the degree of urge incontinence change at 6 weeks and 6 months on 24-h pad test. Secondary outcomes were changes in leaks and voids per day measured on 3-day bladder diary and quality of life measures. Microbiological data were collected at all visits.

RESULTS

Although 278 women were screened, only 36 were randomized and 33 (91.7%) completed the trial. Leakage on 24-h pad test decreased at 6 months by 75 g in patients receiving antibiotics versus 35 g in placebo. Cure of urge incontinence occurred at 6 months in 10/21 (48%) of antibiotics versus 2/12 (17%) of placebo. Clinical override, necessitating treatment of cystitis, occurred in 41.6% of placebo versus 16.7% of the antibiotic group by 6 months.

CONCLUSION

Despite the small sample size, the study showed a significant reduction in pad leakage and leaks per day over 24 h in the active treatment group over a 6-month period. Nearly half of patients on placebo had disabling urinary tract infection symptoms that required clinical override treatment.

Australian and New Zealand Medical Students' Attitudes and Confidence Towards Providing Nutrition Care in Practice

The prevalence of lifestyle-related chronic disease is increasing. Doctors in primary care are ideally placed to support patient nutrition care, but recent reviews show education is still lacking. This study aimed to identify medical students’ attitudes towards the role of nutrition in health, nutrition knowledge, and perceptions of nutrition education, in postgraduate (Australia) and undergraduate (New Zealand) programs in order to identify gaps in nutrition knowledge and skills to better inform future education. Second-year graduate and third-year undergraduate students participated in semi-structured focus groups and interviews. A general inductive approach was used to investigate students’ (1) attitudes toward the role of nutrition in health, (2) nutrition knowledge based on nutrition-specific competencies and (3) perceived adequacy of nutrition education received. Interviews (nine) and focus groups (seven) identified four common themes: (1) role of medical practitioners in nutrition care, (2) barriers to nutrition education, (3) nutrition knowledge, and (4) nutrition-related skills. Students perceive that doctors are well-placed to provide some level of nutrition care, but poor translation of nutrition knowledge to clinical contexts is a key limitation in nutrition education. In summary, nutrition education may be insufficient to support the nutrition-related competency development of the undergraduate and postgraduate student participants in this study. Focusing on the integration of these skills into the curriculum may be a priority.

Purinergic P2X7 receptors as therapeutic targets in interstitial cystitis/bladder pain syndrome; key role of ATP signaling in inflammation

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic lower urinary tract condition. Patients with IC/BPS suffer from debilitating pain and urinary urgency. The underlying etiology of IC/BPS is unknown and as such current treatments are mostly symptomatic with no real cure. Many theories have been proposed to describe the etiology of IC/BPS, but this review focuses on the role of inflammation. In IC/BPS patients, the permeability of the urothelium barrier is compromised and inflammatory cells infiltrate the bladder wall. There are increased levels of many inflammatory mediators in patients with IC/BPS and symptoms such as pain and urgency that have been associated with the degree of inflammation. Recent evidence has highlighted the role of purinergic receptors, specifically the P2X7 receptor, in the process of inflammation. The results from studies in animals including cyclophosphamide-induced hemorrhagic cystitis strongly support the role of P2X7 receptors in inflammation. Furthermore, the deletion of the P2X7 receptor or antagonism of this receptor significantly reduces inflammatory mediator release from the bladder and improves symptoms. Research results from IC/BPS patients and animal models of IC/BPS strongly support the crucial role of inflammation in the pathophysiology of this painful disease. Purinergic signaling and purinergic receptors, especially the P2X7 receptor, play an undisputed role in inflammation. Purinergic receptor antagonists show positive results in treating different symptoms of IC/BPS.

The P2X7 receptor is not essential for development of imiquimod-induced psoriasis-like inflammation in mice

Psoriasis is a chronic inflammatory skin disorder, characterised by epidermal hyperplasia (acanthosis) and leukocyte infiltration of the skin. Current therapies are inadequate, highlighting the need for new therapeutic targets. The P2X7 receptor is implicated in the pathogenesis of psoriasis. This study investigated the role of P2X7 in imiquimod (IMQ)-induced psoriasis-like inflammation. Topically applied IMQ caused twofold greater ear swelling in BALB/c mice compared to C57BL/6 mice, which encode a partial loss-of-function missense mutation in the P2RX7 gene. However, there was no difference in histological skin pathology (acanthosis and leukocyte infiltration) between the two strains. IMQ treatment up-regulated P2X7 expression in skin from both mouse strains. Additionally, IMQ induced ATP release from cultured human keratinocytes, a process independent of cell death. Injection of the P2X7 antagonist Brilliant Blue G (BBG) but not A-804598 partly reduced ear swelling compared to vehicle-injected control mice. Neither antagonist altered skin pathology. Moreover, no difference in ear swelling or skin pathology was observed between C57BL/6 and P2X7 knock-out (KO) mice. Flow cytometric analysis of IMQ-treated skin from C57BL/6 and P2X7 KO mice demonstrated similar leukocyte infiltration, including neutrophils, macrophages and T cells. In conclusion, this study demonstrates that P2X7 is not essential for development of IMQ-induced psoriasis-like inflammation but does not exclude a role for this receptor in psoriasis development in humans or other mouse models of this disease.

'Involve Me and I Learn': Development of an Assessment Program for Research and Critical Analysis

Evidence-based medical practice is best achieved by developing research understanding in medical practitioners. To this end, medical councils worldwide increasingly recognise the importance of medical schools graduating students with well-developed research skills and research capacity. To meet this need, the principles of programmatic assessment were implemented in designing a research and critical analysis curriculum and assessment program that aimed to enhance the research and critical analysis skills of medical students. The program was developed by mapping assessment tasks to a research capabilities framework that was in turn scaffolded to different levels of Miler's pyramid. The curriculum and assessments were integrated with the science, clinical, and professional aspects of the medical course. The progressive longitudinal development of research skills, with feedback and academic mentoring, culminated in the students' capacity to undertake an independent research project. Designing an assessment program for learning encouraged students to develop their research capacity by involving them in their learning.

Altered urothelial ATP signaling in a major subset of human overactive bladder patients with pyuria

Overactive Bladder (OAB) is an idiopathic condition, characterized by urgency, urinary frequency, and urgency incontinence, in the absence of routinely traceable urinary infection. We have described microscopic pyuria (≥10 wbc/μl) in patients suffering from the worst symptoms. It is established that inflammation is associated with increased ATP release from epithelial cells, and extracellular ATP originating from the urothelium following increased hydrostatic pressure is a mediator of bladder sensation. Here, using bladder biopsy samples, we have investigated urothelial ATP signaling in OAB patients with microscopic pyuria. Basal, but not stretch-evoked, release of ATP was significantly greater from the urothelium of OAB patients with pyuria than from non-OAB patients or OAB patients without pyuria (<10 wbc/μl). Basal ATP release from the urothelium of OAB patients with pyuria was inhibited by the P2 receptor antagonist suramin and abolished by the hemichannel blocker carbenoxolone, which differed from stretch-activated ATP release. Altered P2 receptor expression was evident in the urothelium from pyuric OAB patients. Furthermore, intracellular bacteria were visualized in shed urothelial cells from ∼80% of OAB patients with pyuria. These data suggest that increased ATP release from the urothelium, involving bacterial colonization, may play a role in the heightened symptoms associated with pyuric OAB patients.

Correlation between cystometric volumes, ATP release, and pH in women with overactive bladder versus controls

AIMS

In the bladder, ATP is an important signaling molecule, which is released by bladder stretch and acid. We hypothesized that ATP might play a unique role in patients with OAB, characterized by low bladder volumes at first desire to void (FDV) and maximal cystometric capacity (MCC) and symptoms of frequency/urgency [mild bladder pain syndrome (BPS)]. Our aim was to investigate the correlation between ATP release and urodynamic parameters, as well as urine pH, in OAB patients.

METHODS

Routine cystometry was performed in a consecutive series of 249 women. The voided urodynamic fluid (VUF) was stored at -20°C and ATP measured using bioluminescence. Catheter urine was collected for pH measurement. Correlations between two factors were tested by linear regression analysis.

RESULTS

Subjects with urinary tract infection, voiding dysfunction, and detrusor overactivity (DO) were excluded. For OAB patients (n = 25), there was an inverse correlation between ATP concentration in VUF and FDV (r(2)  = 0.25; P = 0.01) but not MCC. This was not seen in controls (n = 69). In OAB, but not controls, there was a significant reverse correlation (r(2)  = 0.16; P = 0.047) between ATP in VUF and urine pH. Urine pH was not significantly correlated with MCC in either group.

CONCLUSIONS

In OAB patients, ATP is an important factor for initial perception of need to urinate (as indicated by FDV). This is similar to our previous findings in patients with DO, suggesting that ATP may mediate initial afferent sensation in patients with bladder dysfunctions characterized by urgency. ATP release was also strongly affected by urine pH, in patients with OAB (at FDV).

Decreased intravesical adenosine triphosphate in patients with refractory detrusor overactivity and bacteriuria

PURPOSE

Although several studies have examined the relationship between adenosine triphosphate release from the urothelium and bladder sensations including painful filling and urgency, the association between bacteriuria and urothelial adenosine triphosphate release has not been well studied. We evaluated women with refractory detrusor overactivity who were experiencing an acute exacerbation of detrusor overactivity symptoms including frequency, urgency and nocturia (and/or urge incontinence). We measured changes in intravesical adenosine triphosphate levels in these women with and without bacteriuria.

MATERIALS AND METHODS

In this prospective cohort study women with refractory detrusor overactivity were invited to our unit during acute symptomatic exacerbation. On presentation a catheter urine specimen was collected and 50 ml normal saline instilled into the bladder to evoke gentle stretch, with removal after 5 minutes. Adenosine triphosphate concentrations were determined on fresh washings using a bioluminescence assay.

RESULTS

The incidence of bacteriuria 10(3) cfu/ml or greater was 27% (15 of 56 specimens) during the 16-month study period. Adenosine triphosphate concentrations were lower during episodes of bacteriuria in the overall cohort (p = 0.0013) and paired samples from individual patients (p = 0.031) compared to episodes of sterile urine.

CONCLUSIONS

In the first study on the subject to our knowledge, we demonstrated a striking difference between adenosine triphosphate levels measured in the presence and absence of bacteriuria in this patient group.

Host-pathogen checkpoints and population bottlenecks in persistent and intracellular uropathogenic Escherichia coli bladder infection

Bladder infections affect millions of people yearly, and recurrent symptomatic infections (cystitis) are very common. The rapid increase in infections caused by multidrug-resistant uropathogens threatens to make recurrent cystitis an increasingly troubling public health concern. Uropathogenic Escherichia coli (UPEC) cause the vast majority of bladder infections. Upon entry into the lower urinary tract, UPEC face obstacles to colonization that constitute population bottlenecks, reducing diversity, and selecting for fit clones. A critical mucosal barrier to bladder infection is the epithelium (urothelium). UPEC bypass this barrier when they invade urothelial cells and form intracellular bacterial communities (IBCs), a process which requires type 1 pili. IBCs are transient in nature, occurring primarily during acute infection. Chronic bladder infection is common and can be either latent, in the form of the quiescent intracellular reservoir (QIR), or active, in the form of asymptomatic bacteriuria (ASB/ABU) or chronic cystitis. In mice, the fate of bladder infection, QIR, ASB, or chronic cystitis, is determined within the first 24 h of infection and constitutes a putative host-pathogen mucosal checkpoint that contributes to susceptibility to recurrent cystitis. Knowledge of these checkpoints and bottlenecks is critical for our understanding of bladder infection and efforts to devise novel therapeutic strategies.

Acid and stretch, but not capsaicin, are effective stimuli for ATP release in the porcine bladder mucosa: Are ASIC and TRPV1 receptors involved?

Stretch-evoked ATP release from the bladder mucosa is a key event in signaling bladder fullness. Our aim was to examine whether acid and capsaicin can also release ATP and to determine the receptors involved, using agonists and antagonists at TRPV1 and acid-sensing ion channels (ASICs). Strips of porcine bladder mucosa were exposed to acid, capsaicin or stretch. Strip tension was monitored. Bath fluid was collected for ATP measurement. Gene expression of ASICs and TRPV1 in porcine bladders was quantified using quantitative real-time PCR (qRT-PCR). Stretch stimulus (150% of original length) repeatedly and significantly increased ATP release to approximately 45 times basal release. Acid (pH 6.5, 6.0, 5.6) contracted mucosal strips and also increased ATP release up to 30-fold, without evidence of desensitization. Amiloride (0.3 μM) reduced the acid-evoked ATP release by approximately 70%, while capsazepine (10 μM) reduced acid-evoked ATP release at pH 6.0 and pH 5.6 (by 68% and 61%, respectively). Capsaicin (0.1-10 μM) was ineffective in causing ATP release, and also failed to contract porcine mucosal or detrusor strips. Gene expression for ASIC1, ASIC2, ASIC3 and TRPV1 was seen in the lateral wall, dome, trigone and neck of both detrusor and mucosa. In conclusion, stretch and acid induce ATP release in the porcine bladder mucosa, but capsaicin is ineffective. The pig bladder is a well-known model for the human bladder, however these data suggest that it should be used with caution, particularly for TRPV1 related studies.

Porcine bladder urothelial, myofibroblast, and detrusor muscle cells: characterization and ATP release

ATP is released from the bladder mucosa in response to stretch, but the cell types responsible are unclear. Our aim was to isolate and characterize individual populations of urothelial, myofibroblast, and detrusor muscle cells in culture, and to examine agonist-stimulated ATP release. Using female pig bladders, urothelial cells were isolated from bladder mucosa following trypsin-digestion of the luminal surface. The underlying myofibroblast layer was dissected, minced, digested, and cultured until confluent (10–14 days). A similar protocol was used for muscle cells. Cultures were used for immunocytochemical staining and/or ATP release investigations. In urothelial cultures, immunoreactivity was present for the cytokeratin marker AE1/AE3 but not the contractile protein α-smooth muscle actin (α-SMA) or the cytoskeletal filament vimentin. Neither myofibroblast nor muscle cell cultures stained for AE1/AE3. Myofibroblast cultures partially stained for α-SMA, whereas muscle cultures were 100% stained. Both myofibroblast and muscle stained for vimentin, however, they were morphologically distinct. Ultrastructural studies verified that the suburothelial layer of pig bladder contained abundant myofibroblasts, characterized by high densities of rough endoplasmic reticulum. Baseline ATP release was higher in urothelial and myofibroblast cultures, compared with muscle. ATP release was significantly stimulated by stretch in all three cell populations. Only urothelial cells released ATP in response to acid, and only muscle cells were stimulated by capsaicin. Tachykinins had no effect on ATP release. In conclusion, we have established a method for culture of three cell populations from porcine bladder, a well-known human bladder model, and shown that these are distinct morphologically, immunologically, and pharmacologically.

Immunocytochemical characterisation of cultures of human bladder mucosal cells

Background

The functional role of the bladder urothelium has been the focus of much recent research. The bladder mucosa contains two significant cell types: urothelial cells that line the bladder lumen and suburothelial interstitial cells or myofibroblasts. The aims of this study were to culture these cell populations from human bladder biopsies and to perform immunocytochemical characterisation.

Methods

Primary cell cultures were established from human bladder biopsies (n = 10). Individual populations of urothelial and myofibroblast-like cells were isolated using magnetic activated cell separation (MACS). Cells were slow growing, needing 3 to 5 weeks to attain confluence.

Results

Cytokeratin 20 positive cells (umbrella cells) were isolated at primary culture and also from patients' bladder washings but these did not proliferate. In primary culture, proliferating cells demonstrated positive immunocytochemical staining to cytokeratin markers (AE1/AE3 and A0575) as well fibroblasts (5B5) and smooth muscle (αSMA) markers. An unexpected finding was that populations of presumptive urothelial and myofibroblast-like cells, isolated using the MACS beads, stained for similar markers. In contrast, staining for cytokeratins and fibroblast or smooth muscle markers was not co-localised in full thickness bladder sections.

Conclusions

Our results suggest that, in culture, bladder mucosal cells may undergo differentiation into a myoepithelial cell phenotype indicating that urothelial cells have the capacity to respond to environmental changes. This may be important pathologically but also suggests that studies of the physiological function of these cells in culture may not give a reliable indicator of human physiology.

Does adenosine triphosphate released into voided urodynamic fluid contribute to urgency signaling in women with bladder dysfunction?

PURPOSE

Adenosine triphosphate released from urothelium during stretch stimulates afferent nerves and conveys information on bladder fullness. We measured adenosine triphosphate released during cystometric bladder filling in women with idiopathic detrusor overactivity and stress incontinence (controls), and assessed whether the level of released adenosine triphosphate is related to cystometric parameters.

MATERIALS AND METHODS

Routine cystometry was done in 51 controls and 48 women with detrusor overactivity who were 28 to 87 years old. Voided urodynamic fluid was collected and stored at -30 C. Adenosine triphosphate was measured by a bioluminescence assay.

RESULTS

Adenosine triphosphate levels were similar in voided urodynamic fluid of controls and patients with detrusor overactivity (p = 0.79). A significant inverse correlation was seen between adenosine triphosphate and maximal cystometric capacity in controls (p = 0.013), and between voided volume and adenosine triphosphate in controls (p = 0.015) and detrusor overactivity cases (p = 0.019). A significant correlation between first desire to void and adenosine triphosphate was also noted in detrusor overactivity cases (p = 0.033) but not in controls (p = 0.58). No correlation was seen between adenosine triphosphate and detrusor pressure during filling or voiding.

CONCLUSIONS

Adenosine triphosphate measurement in voided urodynamic fluid is a novel approach to understanding signals that may contribute to the urgency sensation (a sudden compelling desire to pass urine). The inverse correlation between adenosine triphosphate in voided urodynamic fluid and first desire to void suggests that adenosine triphosphate has a role in modulating the early filling sensation in patients with detrusor overactivity.

Role of fesoterodine in the treatment of overactive bladder

Muscarinic receptors have long been the target receptors for treatment of patients with overactive bladder (OAB). These patients experience symptoms of urgency, urinary frequency and nocturia, with or without urge incontinence (the involuntary leakage of urine associated with urge). Fesoterodine, a pro-drug, structurally and functionally related to tolterodine, is the newest agent developed for the treatment of OAB. Fesoterodine is broken down to the active metabolite, 5-hydroxy-methyl-tolterodine (5-HMT) by non-specific esterases. This metabolism results in the complete breakdown of the parent compound and is responsible for dose related improvements in clinical efficacy and health related quality of life. Like other antimuscarinic agents including tolterodine, fesoterodine is associated with improvements in clinical variables related both to bladder filling (decreasing micturition frequency and increasing mean voided volume) and urgency (urgency and urge incontinence episodes). Improvements in health related quality of life following treatment with fesoterodine is indicated by improvements in 7 of the 9 variables measured by the King’s Health Questionnaire. Also like other antimuscarinic agents, fesoterodine use is associated with adverse events including dry mouth. However the incidence of dry mouth is reduced with fesoterodine, compared to oxybutynin, due to the improved bladder selectivity of 5-HMT.

Release of ATP from rat urinary bladder mucosa: role of acid, vanilloids and stretch

BACKGROUND AND PURPOSE

ATP, released from urothelial cells, modulates afferent nerve firing from the urinary bladder. Here, we have characterized ATP release from the rat bladder mucosa in response to acid, capsaicin, electrical field stimulation (EFS) and stretch, using agonists and antagonists at transient receptor potential vanilloid receptor 1 (TRPV1) and acid-sensing ion channels (ASICs).

EXPERIMENTAL APPROACH

Rat mucosal strips (containing urothelium and lamina propria) in Perspex microbaths were superfused with Krebs solution. ATP was measured after exposure of matched strips to acid (pH 6.6-5.0), capsaicin (0.1-10 microM), EFS or stretch (150% of original length).

KEY RESULTS

Median basal ATP release was 3.46 nmol g(-1). The mucosal strips responded to stimuli with potency order (median, IQR): acid (pH 5.6-6.0) 286 (103-555) > 10 microM capsaicin 188 (117-431) > 10 Hz EFS 63.0 (13.3-96.4) > stretch 24.4 (6.73-55.1) nmol ATP g(-1). ATP release in response to acid was pH dependent (P < 0.05). Responses to capsaicin did not desensitize nor were they concentration dependent. TRPV1 antagonist, capsazepine (10 microM) abolished capsaicin-evoked ATP release, and reduced acid-evoked (pH 6.5) release to 30% (P < 0.001). The ASIC channel antagonists gadolinium (0.1 mM) and amiloride (0.3 microM) reduced (P < 0.05) the acid-evoked (pH 6.5) release to 40 and 6.5% respectively. ASIC (ASIC1, ASIC2a, ASIC2b, ASIC3) and two TRPV1 gene products were detected in mucosal and detrusor extracts.

CONCLUSIONS AND IMPLICATIONS

Capsaicin (at TRPV1) and acid (at both TRPV1 and ASIC) induce ATP release from the rat bladder mucosa. This ATP appears to be principally of urothelial origin. This study highlights the importance of ATP and acid as signalling molecules in modulating bladder function.

Glutathione and catalase suppress TGFbeta-induced cataract-related changes in cultured rat lenses and lens epithelial explants

PURPOSE

The damaging effects of oxidative stress and transforming growth factor-beta (TGFbeta)-induced transdifferentiation of lens epithelial cells have both been implicated independently in the etiology of cataract. The aim of this study was to investigate whether the presence of antioxidant systems in the lens influences the ability of lens epithelial cells to respond to TGFbeta.

METHODS

Whole lenses from young rats were cultured with or without TGFbeta in the presence or absence of reduced glutathione (GSH). Lens epithelial explants from weanling rats were used to investigate the effects of GSH and catalase on TGFbeta-induced cataract-related changes. Lenses were monitored for opacification for three to four days, photographed, and then processed for routine histology. Explants were assessed by phase contrast microscopy, enzyme-linked immunosorbent assay (ELISA) of alpha-smooth muscle actin (alphaSMA), and/or immunolocalization of alphaSMA and Pax6, markers for transdifferentiation and normal lens epithelial phenotype, respectively.

RESULTS

In cultured lenses, GSH strongly suppressed TGFbeta-induced opacification and subcapsular plaque formation. In explants, both GSH and catalase suppressed changes typically associated with TGFbeta-induced transdifferentiation including wrinkling of the lens capsule, cell-surface blebbing, apoptotic cell loss, induction of alphaSMA, and loss of Pax6 expression.

CONCLUSIONS

This study suggests that antioxidant systems present in the normal lens, which protect the epithelium against the damaging effects of reactive oxygen species, may also serve to protect it against the potentially cataractogenic effects of TGFbeta. Taken together with other recent studies, it also raises the possibility that TGFbeta may induce cataract-related changes in lens epithelial cells via release of hydrogen peroxide.

Comparison of receptor binding characteristics of commonly used muscarinic antagonists in human bladder detrusor and mucosa

Recent studies have described muscarinic receptors on the mucosa and the detrusor of the human urinary bladder. Muscarinic receptor antagonists are effective in the treatment of overactive bladder (OAB), but their site(s) of action and actual therapeutic target are unclear. Our aim was to compare, in human bladder mucosa and detrusor, the radioligand binding characteristics of newer, clinically effective agents: darifenacin, its hydroxylated metabolite UK-148,993, fesoterodine, solifenacin, tolterodine, and trospium. Specimens were collected from asymptomatic patients (50-72 years old) undergoing open bladder surgery. Radioligand binding studies with the muscarinic antagonist [3H]quinuclidinyl benzilate (QNB) were performed separately on detrusor and mucosal membranes. All antagonists displayed high affinity when competing for [3H]QNB binding in both detrusor and mucosa. Inhibition constants were also obtained for all antagonists against individual muscarinic receptor subtypes expressed in Chinese hamster ovary cells. Here, fesoterodine showed anomalous binding results, suggesting that some conversion to its metabolite had occurred. Global nonlinear regression analysis of bladder binding data with five antagonists demonstrated 82% low-affinity sites in mucosa and 78% low-affinity sites in detrusor, probably representing M(2)/M(4) receptors. There was an excellent correlation (r(2) = 0.99) of low-affinity global estimates between detrusor and mucosa, whereas the corresponding high-affinity estimates ( approximately 20% of sites) were dissimilar. In conclusion, commonly used and clinically effective muscarinic receptor antagonists bind to receptors located on the bladder mucosa and the detrusor, providing support for the hypothesis that muscarinic receptors in the mucosa may represent an important site of action for these agents in OAB.

Nitric oxide, a survival factor for lens epithelial cells

PURPOSE

Nitric oxide (NO) is capable of promoting either cell death or cell survival depending on cell type and experimental conditions. In this study, the possible effects of NO on the viability of lens epithelial cells were investigated in an explant model used previously to identify cellular changes associated with posterior capsule opacification following cataract surgery.

METHODS

Rat lens epithelial explants prepared from weanling rats were cultured in a serum-free medium for five days with or without the addition of the nitric oxide synthase inhibitor, L-N(omega)-nitro-L-arginine methyl ester (L-NAME), using the inactive enantiomer D-NAME as a control. Alternatively, explants were cultured for nine days with or without the NO donor, sodium nitroprusside. Explants were assessed morphologically and immunohistochemically or by determining DNA content.

RESULTS

In the presence of L-NAME but not in controls, progressive rounding up and detachment of cells from the lens capsule occurred, leading to extensive cell loss. Affected cells showed apoptosis-like cell-surface blebbing and nuclear fragmentation. Conversely, inclusion of sodium nitroprusside suppressed the morphological changes and spontaneous cell loss that occurred when sparsely covered explants were cultured for nine days, increased cell coverage fourfold during that period, and prevented the expression of the transdifferentiation markers alpha-smooth muscle actin and fibronectin. In addition, whereas L-NAME exacerbated cell loss induced by culturing with 50 pg/ml transforming growth factor-beta2, sodium nitroprusside offered protection.

CONCLUSIONS

This study points to a previously unidentified role for NO as an endogenously produced survival factor for lens epithelial cells, raising the possibility of using NO deprivation as a means of removing residual lens cells following cataract surgery and thereby preventing posterior capsule opacification.

Molecular characterization of M2 and M3 muscarinic receptor expression in bladder from women with refractory idiopathic detrusor overactivity

OBJECTIVE

To examine the expression of muscarinic M2 and M3 receptors in human bladder detrusor and mucosa, from controls and patients with idiopathic detrusor overactivity (IDO), as antimuscarinic agents are the primary pharmacological treatment for IDO.

PATIENTS AND METHODS

Biopsies from the bladder body were collected at cystoscopy from 20 women with urodynamically confirmed refractory IDO (age range 25-86 years); biopsies were also collected from 30 asymptomatic female controls (age range 32-87 years). Samples were collected into RNA extraction medium and dissected into mucosa (urothelium plus lamina propria) and detrusor. RNA was extracted and the expression of M2 and M3 receptor mRNA determined by quantitative competitive reverse transcription-polymerase chain reaction. Results were normalized to beta-actin expression in the same sample.

RESULTS

Expression of M3 receptor mRNA, in mucosa of IDO patients (median 0.057 pg M3/100 ng total RNA; interquartile range 0.03-0.13, 12 samples), was four times (P = 0.039, Mann-Whitney) lower than from the control (median 0.22 pg M3/100 ng total RNA; 0.13-0.51, 11 samples). The expression of muscarinic M3 receptor mRNA was higher (14-35 times) in detrusor (control median 3.17; 26 samples) than in mucosa and did not change in IDO (median 2.03; 14 samples). M2 expression was not significantly different with region or with IDO.

CONCLUSIONS

These data show that M3 muscarinic receptor mRNA expression was significantly less in mucosa from IDO patients than from age-matched controls. The role of mucosal M3 receptors is unknown at present and elucidation of this role might provide a greater understanding of the aetiology of IDO.

The molecular basis of urgency: regional difference of vanilloid receptor expression in the human urinary bladder

AIM

Treatments targeting vanilloid receptor TRPV1 are effective in some bladder disorders. Our aim was to determine the expression profiles of TRPV1 in regions of human bladder and test the hypothesis that there would be an upregulation of TRPV1 in mucosa of patients with bladder hypersensitivity but not idiopathic detrusor overactivity (IDO).

MATERIALS AND METHODS

Women with sensory urgency (SU), interstitial cystitis (IC), and IDO were investigated by videourodynamics and cystoscopy. Control biopsies were used for comparison. Biopsies were dissected into mucosa and muscle, and evaluated for TRPV1 mRNA expression using quantitative competitive RT-PCR (QC-RT-PCR).

RESULTS

TRPV1 mRNA from SU trigonal mucosa was significantly higher than control trigonal mucosa or SU bladder body mucosa. In contrast, in IDO patients, there was no difference between trigonal mucosa and body mucosa. In IC biopsies, RNA quality was substandard and unable to be used for analysis. The most striking finding was that TRPV1 mRNA expressed in SU trigonal mucosa was significantly inversely correlated with the bladder volume at first sensation of filling during cystometry. No such relationship was seen for IDO trigonal mucosa. No difference was seen in bladder body mucosa from any disease groups compared with age-matched control.

CONCLUSIONS

The symptoms of SU were associated with the increased expression of TRPV1 mRNA in the trigonal mucosa. No upregulation or regional differences of TRPV1 mRNA were seen in IDO patients. TRPV1 may play a role in SU and premature first bladder sensation on filling.

Age-related changes of P2X(1) receptor mRNA in the bladder detrusor from men with and without bladder outlet obstruction

The urinary bladder purinergic system is reported to change with age and with bladder dysfunction. Here, we examined the expression of purinergic P2X(1) receptors in detrusor and mucosa (urothelium+lamina propria) from male control bladder and investigated age-related P2X(1) receptor mRNA expression in control and obstructed detrusor. Biopsy specimens were obtained at cystoscopy from control patients (n=46, age range 30-86years) and patients diagnosed with outlet obstruction (n=29, 46-88years). Calponin expression (measured by RT-PCR) was similar in control and obstructed detrusor and did not change with age. Quantitative competitive RT-PCR was used to measure P2X(1) receptor and GAPDH mRNA in control and obstructed detrusor. P2X(1) receptor mRNA expression was 9-fold (p<0.0001) higher in the detrusor than in the mucosa. Expression of mRNA for the internal control GAPDH remained stable with age and across control and obstructed detrusor. No difference in P2X(1) receptor expression was observed between control and obstructed detrusor (p=0.35). However, an age-related decrease in P2X(1) mRNA expression was observed in control (n=27; p=0.0054; Spearman coefficient r=-0.520) but not obstructed detrusor (n=19; p=0.093; r=-0.396). Downregulation of P2X(1) mRNA expression might occur as a result of an increased component of neural ATP release in the aging bladder.

Muscarinic receptor subtypes in human bladder detrusor and mucosa, studied by radioligand binding and quantitative competitive RT-PCR: changes in ageing

1. We investigated muscarinic receptors in the detrusor and mucosa of the human bladder body. Radioligand-binding studies with [(3)H]QNB were conducted using specimens collected from patients (36-77 years) with normal bladder function, undergoing surgery. For RT-PCR, biopsies of normal bladder were obtained from patients (30-88 years) undergoing check cystoscopy. 2. Binding of [(3)H]QNB in detrusor (n=20) was of high affinity (K(D) 77.1 (55.2-99.0) pM) and capacity (B(max) 181+/-7 fmol mg protein(-1)). Similar values were obtained in mucosa (n=6) (K(D) 100.5 (41.2-159.9) pM; B(max) 145+/-9 fmol mg protein(-1)). 3. Competition-binding experiments in detrusor membranes with muscarinic receptor antagonists including trospium, darifenacin, 4-DAMP, methoctramine, AQ-RA 741, AF-DX 116 and pirenzepine indicated a receptor population of 71% M(2), 22% M(3) and 7% M(1). In the mucosa, 75% of sites were M(2) receptors, with 25% M(3)/M(5). 4. Using RT-PCR, expression of M(1), M(2), M(3) and M(5) mRNA was demonstrated in both detrusor and mucosa. 5. The presence of a high density of mainly M(2) muscarinic receptors in the mucosa appears to be a novel finding and raises the question of their physiological significance and the source of their endogenous ligand. 6. There was a negative correlation of receptor number (B(max)) with age in detrusor muscle from male patients (P=0.02). Quantitative competitive RT-PCR demonstrated a selective age-related decrease in mRNA for muscarinic M(3) but not M(2) receptors, in both male (P<0.0001) and female (P=0.019) detrusor. These findings correspond with reports of decreased detrusor contractility with ageing.

Effects of dexamethasone on posterior capsule opacification-like changes in a rat lens explant model

PURPOSE

Many patients whose sight is initially restored by cataract surgery eventually suffer secondary loss of vision because of posterior capsule opacification (PCO; after-cataract), a condition in which lens epithelial cells left behind at surgery become aberrant and migrate into the light path. The aim of this study was to determine whether dexamethasone (DEX), an anti-inflammatory agent widely used before and after cataract surgery, influences the behavior of lens cells under conditions relevant to PCO development.

METHODS

An established rat PCO model was used in which explanted epithelial cells attached to the lens capsule are exposed sequentially to TGFbeta2 and FGF-2. Cultures with or without DEX (100 nM), and appropriate controls, were maintained for up to 30 days and assessed by light and scanning electron microscopy or immunolocalization of PCO markers (alpha-smooth muscle actin or fibronectin) or a marker for lens epithelial cell phenotype (Pax-6).

RESULTS

In the absence of DEX, explants become multilayered and plaques that express PCO markers form. Cells tend to gather up into the plaques, leaving the surrounding lens capsule denuded. Changes in lens cell behavior with addition of DEX included rapid formation of long, needle-like cells, less extracellular matrix deposited on explant surface, and plaques surrounded by a monolayer of migratory cells. Immunolocalization confirmed that the latter were not normal lens epithelial cells.

CONCLUSIONS

Lens cell behavior in this PCO model was significantly affected by inclusion of DEX, highlighting the possibility that its use as an anti-inflammatory at the time of cataract surgery may influence PCO development.

FGF-2 counteracts loss of TGFbeta affected cells from rat lens explants: implications for PCO (after cataract)

PURPOSE

While cataract surgery initially benefits most patients, many suffer secondary loss of vision because of posterior capsule opacification (PCO). Lens epithelial cells left behind at surgery become aberrant and migrate into the light path. TGF-beta (TGFbeta) appears to play a key role in this process by inducing the cells to undergo an epithelial-mesenchymal transition. Paradoxically, it also typically induces them to undergo apoptotic death. The present study was undertaken to investigate the hypothesis that FGF plays a role in PCO formation by promoting the survival of abnormal cells with PCO-like characteristics.

METHODS

Rat lens epithelial explants were cultured for one day with TGFbeta2 (25-100 pg/ml) then in control medium with or without FGF-2 (5-100 ng/ml) for up to 31 days, with assessment by light and scanning electron microscopy and immunolocalization.

RESULTS

Survival of TGFbeta treated cells was promoted by FGF-2 but not by EGF, PDGF, IGF, or HGF. In the absence of FGF virtually all cells were lost from explants within 5 days. However, when FGF was included cells remained viable throughout culture. These cells, which no longer expressed the lens epithelial marker Pax6, exhibited immunoreactivity for non-lens cell proteins associated with PCO (alpha-smooth muscle actin, type I collagen, and fibronectin) and also beta-crystallin. FGF inclusion also promoted ECM production, multilayering, and plaque formation, features of PCO known to contribute to visual loss.

CONCLUSIONS

This study points to a key role for FGF in the etiology of PCO and suggests that FGF inhibitors may be useful in preventing PCO.

Exacerbation of TGF-beta-induced cataract by FGF-2 in cultured rat lenses

PURPOSE

Culturing rat lenses with transforming growth factor-beta (TGFbeta) results in the formation of anterior, opaque subcapsular plaques which exhibit many of the features of human subcapsular cataract. The present study was undertaken to determine whether this process is influenced by the presence of fibroblast growth factor (FGF), a normal component of the lens environment in situ.

METHODS

Rat lenses were cultured for 4-8 days with TGFbeta-2, alone or in combination with FGF-2, PDGF-AA, or the growth factor inhibitors poly(4-styrenesulfonic acid) (PSS) and suramin. Responses were assessed by monitoring opacification, by routine histology and immunolocalization of markers for fibrotic change (a-smooth muscle actin, fibronectin, and type I collagen), or by measuring DNA accumulation in the epithelial region.

RESULTS

Supplementing TGFbeta at a barely cataractogenic dose with 2.5-30 ng/ml FGF-2 resulted in a very strong opacification response. The exceptionally large plaques that formed were similar histologically to those induced by TGFbeta alone at higher concentrations and showed immunoreactivity for all markers. PDGF at a concentration equivalent to FGF in terms of proliferative potential did not demonstrate this effect. Addition of either PSS or suramin reduced the opacification response induced by a cataractogenic dose of TGFbeta alone.

CONCLUSIONS

FGF has been identified as a factor capable of exacerbating the cataractogenic effects of TGFbeta. Thus FGF inhibitors, as well as TGFbeta inhibitors, have the potential to protect the lens against TGFbeta-induced cataractous changes.

Muscarinic receptor subtypes in the human colon: lack of evidence for atypical subtypes

Characteristics of muscarinic receptors were investigated in circular muscle from normal human colon. In saturation studies (n=18), binding of [3H]quinuclidinyl benzylate (QNB) was of high affinity (K(d) 87.3 pM) and capacity (B(max) 362+/-27 fmol/mg protein), with no differences between ascending and sigmoid colon. Kinetic studies gave a K(d) of 55 pM. Methoctramine and darifenacin displayed biphasic binding profiles, the high affinity components being compatible with a population of approximately 80+/-5% M(2) and 13+/-2% M(3) muscarinic receptors, respectively. Pirenzepine, mamba toxin 1 and mamba toxin 3 were very weak competitors, indicating negligible expression of muscarinic M(1) and M(4) receptors. Six other subtype-preferring antagonists exhibited K(i) values typical of those reported at cloned human muscarinic M(2) receptors. In the presence of methoctramine, pre-treatment with alkylating agent 4-diphenylacetoxy-N-(2-chloroethyl)-piperidine hydrochloride (4-DAMP mustard) inhibited [3H]quinuclidinyl benzylate binding to 26% of sites. Following alkylation of muscarinic M(3) receptors, darifenacin bound to a single low affinity site, indicating binding to muscarinic M(2) receptors.

Diet can influence the ability of nicotinamide to prevent diabetes in the non-obese diabetic mouse: a preliminary study

BACKGROUND

The non-obese diabetic (NOD) mouse is a widely used model of Type 1 diabetes mellitus (Type 1 DM), which displays many of the characteristics of the disease found in humans. Nicotinamide (NA) is currently being tested in large-scale, multi-centre human trials for the prevention of Type 1 DM in subjects considered 'at risk' of developing the disease. Human trial populations will certainly differ in their dietary patterns and alterations were made to the diet given to NOD mice to determine if this could alter the effect of NA administration on Type 1 DM incidence.

METHODS

The effect of NA in the diet was examined, both with and without carbohydrate in the form of a sucrose supplement, on diabetes incidence and insulitis levels in the NOD mouse. The effects of NA and sucrose were each tested alone as well as in combination.

RESULTS

Diabetes was unaltered using a low dose NA-supplemented diet (625 mg/kg diet). Diabetes incidence was also unaltered using unmodified diet together with drinking water supplemented with either 5% or 10% w/v sucrose or plain water for controls. However, with mice given NA-supplemented diet (625 mg/kg diet) together with sucrose-supplemented or plain water as previously, diabetes was reduced in the NA+10% sucrose group (p<0.001). Finally, a higher dose of NA was given in supplemented diet (1000 mg/kg). Again, neither sucrose nor NA alone altered the incidence of diabetes, but NA treatment combined with a 10% w/v sucrose-supplemented drinking water reduced diabetes incidence (p<0.001). No mice showed alterations in insulitis, blood-glucose or insulin levels with respect to controls.

CONCLUSION

Altering dietary patterns using sucrose can affect the ability of NA to prevent diabetes in the NOD mouse. This finding may be relevant for human studies with NA aimed at preventing Type 1 DM and suggests that diet may need to be monitored or even controlled in these studies.