Evaluation of an online arts-based platform to support the health and well-being of older adults during the COVID-19 pandemic: a cross-sectional survey

OBJECTIVES

The objective of this study was to conduct a formative evaluation of the Art Your Service (AYS) arts-based program to determine the program's potential for improving the social and physical well-being of older adults during the COVID-19 pandemic.

DESIGN, SETTINGS AND PARTICIPANTS

An online questionnaire was administered to the AYS members who consented to be invited to participate in the study. Questionnaire items consisted of a Likert scale and open-ended questions delivered using an online platform (SurveyMonkey). Participants provided feedback on their perceptions and experiences of the AYS program, such as its impact on their health and well-being during the COVID-19 pandemic, the benefits and challenges of participating, and any suggestions for program improvement.

OUTCOME MEASURES AND ANALYSIS

Quantitative data were analyzed using descriptive statistics (frequencies, means with standard deviations), and open-ended questions (qualitative data) were analyzed using content analysis. Outcomes included participant demographics, perceptions about the program, usability (System Usability Scale [SUS]), eHealth literacy (eHealth Literacy Scale), and social isolation (Lubben Social Network Scale; LSNS-6).

RESULTS

Program participants revealed consistent patterns of their perceptions and experiences about the program, including a high satisfaction rate (95%) and a perceived positive impact on participants' health and well-being. The program sessions were perceived to be a well-organized, convenient, and safe way to engage with one another socially during the COVID-19 pandemic. The program usability was also perceived to be high (SUS mean score 86.2). Participants felt a sense of connectedness and had reduced feelings of social isolation. Most participants (75%) reported that the program improved their physical health.

CONCLUSIONS

Findings from this formative evaluation study identified key strengths and opportunities to improve the Art Your Service arts-based program, which can be used to help enhance the program's functioning and long-term sustainability potential.

Factors associated with weight loss and health gains in a structured lifestyle modification programme for adults with severe obesity: a prospective cohort study

Background

Individual responses to behavioural weight loss interventions can vary significantly, and a better understanding of the factors associated with successful treatment might help to target interventions for those who will benefit the most. We sought to identify demographic and clinical characteristics that predicted intervention "success" (defined as ≥5% weight loss) and other health gains in patients with severe obesity attending a ten-week structured lifestyle modification programme.

Methods

We conducted a prospective cohort study of all 1122 patients (751 (66.9%) female, mean age 47.3 ± 11.9 years, mean body mass index (BMI) 46.7 ± 7.8 kgm-2) referred from our hospital-based obesity clinic, who started the structured lifestyle programme between 2012-2019. We compared routine clinical measures such as weight, fitness, blood pressure, lipids and HbA1c at baseline and follow-up. We also used validated questionnaires to quantify anxiety, depression and health-related quality of life.

Results

Of 1122 patients who started, 877 (78.2%) completed the programme and attended for follow up. Of these, 12.8% lost ≥5% body weight. The amount of weight lost was a strong and consistent predictor of improvements in metabolic, cardiovascular, and mental health, even after adjusting for age, sex, programme attendance and baseline fitness. Older age, male sex, being physically active and having lower anxiety and depression scores at baseline predicted greater weight loss. Younger age, depression and longer wait time to start the intervention were associated with drop-out.

Conclusions

In adults with severe obesity completing a structured lifestyle modification programme, older age and good mental health were associated with programme completion and attaining ≥5% weight loss. The magnitude of weight lost was a strong predictor of improvements in cardiovascular, metabolic and mental health associated with programme completion.

MODELS OF OLDER ADULT GROUP ENGAGEMENT TO IMPROVE HEALTH MANAGEMENT

We are studying the use of peer-to-peer group intervention as a means of promoting older adult health self-efficacy and self-management. To explore how older adults have worked together to improve health behaviors, a scoping review was conducted of older adult peer coaching in health maintenance or health improvement groups. Seventeen studies met all search criteria, including interventions examining the value of peer support in self-management of diabetes, a peer led program for fear of falling, and the effect of self-help groups on quality of life. Two models of peer engagement were identified: peer support and mutually supportive environments. Ten studies trained older adults to be peer mentors or leaders with training periods varying from two days to 30 weeks, although many did not include details of the training. The other seven studies examined mutually supportive environments for peer engagement such as a clinician-led with peer-support model, an app-based program with a social support component, and a prevention focused mutual support group. These studies included research comparing self-care and quality of life results after self-help group therapy and a study that analyzed the impact and role of volunteering at a seniors’ centre on maximizing member self-efficacy. While all studies reported on peer self-health engagement, there were many different goals ranging from evaluating health improvement programs to comparing peer and professional health group leadership. One consistent theme was improved perceived self-efficacy though peer group engagement.

Obesity in Adults: A 2022 Adapted Clinical Practice Guideline for Ireland

BACKGROUND

This Clinical Practice Guideline (CPG) for the management of obesity in adults in Ireland, adapted from the Canadian CPG, defines obesity as a complex chronic disease characterised by excess or dysfunctional adiposity that impairs health. The guideline reflects substantial advances in the understanding of the determinants, pathophysiology, assessment, and treatment of obesity.

SUMMARY

It shifts the focus of obesity management toward improving patient-centred health outcomes, functional outcomes, and social and economic participation, rather than weight loss alone. It gives recommendations for care that are underpinned by evidence-based principles of chronic disease management; validate patients' lived experiences; move beyond simplistic approaches of "eat less, move more" and address the root drivers of obesity.

KEY MESSAGES

People living with obesity face substantial bias and stigma, which contribute to increased morbidity and mortality independent of body weight. Education is needed for all healthcare professionals in Ireland to address the gap in skills, increase knowledge of evidence-based practice, and eliminate bias and stigma in healthcare settings. We call for people living with obesity in Ireland to have access to evidence-informed care, including medical, medical nutrition therapy, physical activity and physical rehabilitation interventions, psychological interventions, pharmacotherapy, and bariatric surgery. This can be best achieved by resourcing and fully implementing the Model of Care for the Management of Adult Overweight and Obesity. To address health inequalities, we also call for the inclusion of obesity in the Structured Chronic Disease Management Programme and for pharmacotherapy reimbursement, to ensure equal access to treatment based on health-need rather than ability to pay.

The Experiences of Older Adults with Cannabis and Mental Health: A Scoping Review of the Literature

Following the 2018 federal legalization of cannabis in Canada, there was a drastic increase in older adults reporting marijuana use. Most cannabis research today focuses on children and young adults, however, it is important to acknowledge the potential harms in seniors as well. Aging and substance use presents unique considerations, such as the interactions between cannabis and chronic conditions, multiple comorbidities, polypharmacy, and mental health. The goal of this scoping review was to analyze the literature that addresses mental health outcomes of seniors who use cannabis, in order to answer the main research question: What is the relationship between older adults’ use of cannabis and mental health? Following Arksey and O’Malley’s five-stage framework, 10 electronic databases were searched along with a hand search of references. The search revealed 7000+ peer-reviewed and grey literature sources. 233 full-text sources were assessed for eligibility, with a total of 25 articles included. Thematic content analysis produced four major themes which addressed: (1) Usage characteristics; (2) User characteristics; (3) Outcomes; and (4) Physical and mental health considerations. Findings from this scoping review are positioned in terms of their implications for research, practice, and policy. While more in-depth, qualitative methods are required to develop further research, several harm-reduction strategies may be immediately utilized by both users and healthcare practitioners. It is critical that older adults and their physicians are able to make cannabis-related decisions with evidence-informed guidance to prevent problematic cannabis use and ensure positive mental health outcomes.

Older adult maintaining and improving health self-management through peer supported SMART goal setting

Non-medical interventions to address risk factors (such as reducing smoking, increasing physical activity, and tackling limited social interaction) are needed to help tackle escalating social and financial health costs. Peer supported interventions have been used successfully to support persons’ health self-management; however, there is limited evidence for group interventions facilitated by older adults. A proof-of-concept study by the first author demonstrated the potential of older adults meeting in groups to each create and follow through with a single SMART goal for any area of health over one-month. This study extends SMART goal setting to enhancing health management over six months. Older adult participants from across Ontario will attend virtual SMART goal setting group sessions followed by six monthly support group meetings where they are free to choose any goal, whether a mitigation or a new behavior. Each month the facilitator will assist participants to continue, modify, or set a new goal. At the end participants will complete surveys about their satisfaction with the method, their results and their desire to continue with SMART goals. They will also be asked if they would like to facilitate new groups to continue the spread of peer-supported SMART goal groups. This study is designed to empower older adults to maintain or improve management of their physical, psychological, and/or social health. It will reveal the impact of an older adult created and guided group health intervention on feelings of self-efficacy and well-being.

Distinct expression of select and transcriptome-wide isolated 3'UTRs suggests critical roles in development and transition states

Mature mRNA molecules are expected to be comprised of a 5’UTR, a 3’UTR and a coding region (CDS). Unexpectedly, however, there have been multiple recent reports of widespread differential expression of mRNA 3’UTRs and their cognate coding regions (CDS), reflecting the expression of isolated 3’UTRs (i3’UTRs); these i3’UTRs can be highly expressed, often in reciprocal patterns to their cognate CDS. As with other long non-coding (lncRNAs), isolated 3’UTRs are likely to play an important role in gene regulation, but little is known about the contexts in which they are deployed. To illuminate the functions of i3’UTRs, here we carry out in vitro, in vivo and in silico analyses of differential 3’UTR/CDS mRNA ratio usage across tissues, development and cell state changes both for a select list of developmentally important genes as well as by unbiased transcriptome-wide analyses. Across two developmental paradigms we find a distinct switch from high i3’UTR expression for stem cell related genes in proliferating cells to high CDS for these genes in newly differentiated cells. Unbiased transcriptome analysis across multiple gene sets shows that regardless of tissue, genes with high 3’UTR to CDS ratios belong predominantly to gene ontology categories related to cell-type specific functions. In contrast, the gene ontology categories of genes with low 3’UTR to CDS ratios are similar across tissues and relate to common cellular functions. We further show that, at least for some genes, traditional transcriptional start site genomic elements correspond to identified RNAseq 3’UTR peak regions, suggesting that some i3’UTRs may be generated by de novo transcription. Our results provide critical information from which detailed hypotheses for individual i3’UTRs can be tested, with a common theme that i3’UTRs appear poised to regulate cell-specific gene expression and state.

Effects of a Milk-Based Meal Replacement Program on Weight and Metabolic Characteristics in Adults with Severe Obesity

OBJECTIVE

Low energy meal replacement regimens can induce short-term weight loss in patients with severe obesity, but usually require specially formulated dietary supplements. We sought to determine the effects of a milk-based meal replacement program on anthropometric and metabolic characteristics in adults with severe obesity.

METHODS

We conducted a retrospective cohort study of patients attending our hospital-based bariatric medicine service who completed a 24-week program consisting of eight weeks of milk-based meal replacement followed by weight stabilisation and maintenance phases. Patients were seen fortnightly by the bariatric physician, nurse and dietitian. We assessed changes in anthropometric and metabolic outcomes in completers at 0, 8, 16 and 24 weeks.

RESULTS

Of 105 program completers available for follow-up, 53.3% were female. Mean age was 51.1±11.2 years. Body weight decreased from 144.0±27.6 kg at baseline to 121.1±25.0 kg at 24 weeks (P<0.001), a mean total body weight loss of 15.9±6.0%, with a reduction in body mass index from 50.6±8.0 to 42.6±7.6 kg m^-2 (P<0.001). In patients with diabetes, haemoglobin A1c decreased from 66.3±13.0 to 48.3±13.5 mmol/mol (P<0.001) and diabetes medication use decreased significantly. There were significant improvements also in lipid profiles and reductions in antihypertensive medication use.

CONCLUSION

These preliminary findings suggest that completion of a 24-week milk-based meal replacement program has large effects on important outcomes in adults with severe obesity. However, attrition was high. Prospective assessment of the efficacy, safety, durability and cost-effectiveness of this intervention seems warranted.

Influence of socioeconomic factors on litigation in surgery: Addressing the gap in malpractice literature

The practice of medicine is occasionally volatile and increasingly litigious. Within the specialities, plastic surgery has a high risk, with negative outcomes seen as dissatisfaction, as compared to actual physical harm. To date, most research has focused on potential triggers for litigation, such as poor communication and perceived behavioural deficiencies among physicians. Few studies have addressed patient characteristics or socioeconomic factors. The 'Influence of Socio-Economic Factors on Attitudes Towards Surgery' questionnaire was designed to reflect these goals. It was distributed for a 12-month period to patients in an Emergency Department waiting room. Three hundred twelve completed questionnaires were submitted for analysis. Within the study population, we identified certain socioeconomic trends among those with a low threshold to pursue litigation. Patients with a low threshold to sue were more likely to be male, aged 25-55 years, currently unemployed, without dependents and divorced. However, these parameters did not reach statistical significance. Although these characteristics are interesting, they cannot reliably identify or predict those with a low threshold for litigation. For now, the clinical focus should remain on careful adherence to best practice in an effort to reduce the risk of potential litigation.

Effects of an eight-week supervised, structured lifestyle modification programme on anthropometric, metabolic and cardiovascular risk factors in severely obese adults

BACKGROUND

Lifestyle modification is fundamental to obesity treatment, but few studies have described the effects of structured lifestyle programmes specifically in bariatric patients. We sought to describe changes in anthropometric and metabolic characteristics in a cohort of bariatric patients after participation in a nurse-led, structured lifestyle programme.

METHODS

We conducted a retrospective, observational cohort study of adults with a body mass index (BMI) ≥ 40 kgm(-2) (or ≥ 35 kgm(-2) with significant co-morbidity) who were attending a regional bariatric service and who completed a single centre, 8-week, nurse-led multidisciplinary lifestyle modification programme. Weight, height, waist circumference, blood pressure, HbA1c, fasting glucose and lipid profiles as well as functional capacity (Incremental Shuttle Walk Test) and questionnaire-based anxiety and depression scores before and after the programme were compared in per-protocol analyses.

RESULTS

Of 183 bariatric patients enrolled, 150 (81.9%) completed the programme. Mean age of completers was 47.9 ± 1.2 years. 34.7% were male. There were statistically significant reductions in weight (129.6 ± 25.9 v 126.9 ± 26.1 kg, p < 0.001), BMI (46.3 ± 8.3 v 44.9 ± 9.0 kgm(-2), p < 0.001), waist circumference (133.0 ± 17.1 v 129.3 ± 17.5 cm in women and 143.8 ± 19.0 v 135.1 ± 17.9 cm in men, both p < 0.001) as well as anxiety and depression scores, total- and LDL-cholesterol and triglyceride levels, with an increase in functional capacity (5.9 ± 1.7 v 6.8 ± 2.1 metabolic equivalents of thermogenesis (METS), p < 0.001) in completers at the end of the programme compared to the start. Blood pressure improved, with reductions in systolic and diastolic blood pressure from 135 ± 16.2 to 131.6 ± 17.1 (p = 0.009) and 84.7 ± 10.2 to 81.4 ± 10.9 mmHg (p < 0.001), respectively. The proportion of patients achieving target blood pressure increased from 50.3 to 59.3% (p = 0.04). The proportion of patients with diabetes achieving HbA1c <53 mmol/mol increased from 28.6 to 42.9%, p = 0.02.

CONCLUSIONS

Bariatric patients completing an 8 week, nurse-led structured lifestyle programme had improved adiposity, fitness, lipid profiles, psychosocial health, blood pressure and glycaemia. Further assessment of this programme in a pragmatic randomised controlled trial seems warranted.

Use of plasma "reconstitution" during cardio pulmonary bypass for a heart transplant after previous left ventricular assist device implant surgery

The case report describes a novel technique of pre-emptive plasma "reconstitution" prior to disengagement from cardiopulmonary bypass (CPB) to minimize RV volume overload. The concomitant use of hemoconcentration facilitates volume and blood product management in cardiac transplant after previous left ventricular assist device implant surgery.

Safety and tolerability of transoral Bravo capsule placement after transnasal manometry using a validated conversion factor

OBJECTIVES

To prospectively calculate and validate a conversion factor in healthy volunteers that allows accurate nonsedated, transoral (TO) Bravo capsule placement after transnasal (TN) manometry, and to evaluate the ease and safety of nonendoscopic Bravo placement compared with endoscopic placement.

METHODS

Part 1. Twenty-five healthy volunteers underwent sequential TN and TO esophageal manometry to measure the distance to the lower esophageal sphincter (LES). A TN to TO conversion factor was calculated from these measurements. Part 2. Twenty volunteers underwent TN manometry followed by unsedated TO Bravo capsule placement using the conversion factor calculated in part 1. TN endoscopy then measured the location of the Bravo capsule in relationship to the squamocolumnar junction (SCJ). Part 3. During an 18-month period, 370 consecutive patients referred for a Bravo procedure underwent nonendoscopic, unsedated TO placement (308 patients) or standard endoscopically assisted placement (62 patients).

RESULTS

Part 1. All 25 volunteers completed TN and TO manometry; a conversion factor of 4 cm was calculated. Part 2. Using the calculated conversion factor of 4 cm, a Bravo capsule was deployed TO 5 cm above the proximal border of the LES. The mean +/- standard deviation (SD) TN endoscopic distance to the capsule was 6.0 cm (+/-0.3 cm) above the SCJ. Part 3. A total of 333 patients completed the entire study (90%). Analysis of 48-h pH measurements did not reveal any significant differences between the two groups.

CONCLUSIONS

A reliable and valid conversion factor of 4 cm following TN manometry permits accurate TO placement of the Bravo capsule without endoscopy. TO, unsedated Bravo placement is safe, well tolerated, and may minimize costs and potential risks associated with endoscopy.

Influence of Nitinol wire surface treatment on oxide thickness and composition and its subsequent effect on corrosion resistance and nickel ion release

Medical implants and devices are now used successfully in surgical procedures on a daily basis. Alloys of nickel and titanium, and in particular Nitinol are of special interest in the medical device industry, because of their shape memory and superelastic properties. The corrosion behavior of nitinol in the body is also of critical importance because of the known toxicological effects of nickel. The stability of a NiTi alloy in the physiological environment is dependant primarily on the properties of the mostly TiO(2) oxide layer that is present on the surface. For the present study, a range of nitinol wires have been prepared using different drawing processes and a range of surface preparation procedures. It is clear from the results obtained that the wire samples with very thick oxides also contain a high nickel content in the oxide layer. The untreated samples with the thicker oxides show the lowest pitting potential values and greater nickel release in both long and short-term experiments. It was also found that after long-term immersion tests breakdown potentials increased for samples that exhibited lower values initially. From these results it would appear that surface treatment is essential for the optimum bioperformance of nitinol.

Gene targeting using a promoterless gene trap vector ("targeted trapping") is an efficient method to mutate a large fraction of genes

A powerful tool for postgenomic analysis of mammalian gene function is gene targeting in mouse ES cells. We report that homologous recombination using a promoterless gene trap vector ("targeting trapping") yields targeting frequencies averaging above 50%, a significant increase compared with current approaches. These high frequencies appear to be due to the stringency of selection with promoterless constructs, because most random insertions are silent and eliminated by drug selection. The promoterless design requires that the targeted gene be expressed in ES cells at levels exceeding a certain threshold (which we estimate to be approximately 1% of the transferrin receptor gene expression level, for the secretory trap vector used here). Analysis of 127 genes that had been trapped by random (nontargeted) gene trapping with the same vector shows that virtually all are expressed in ES cells above this threshold, suggesting that targeted and random trapping share similar requirements for expression levels. In a random sampling of 130 genes encoding secretory proteins, about half were expressed above threshold, suggesting that about half of all secretory genes are accessible by either targeted or random gene trapping. The simplicity and high efficiency of the method facilitate systematic targeting of a large fraction of the genome by individual investigators and large-scale consortia alike.

The use of tranexamic acid to reduce blood loss during total knee arthroplasty

HYPOTHESIS

The fall in haemoglobin following unilateral total knee arthroplasty is reduced by tranexamic acid administration.

METHODS

60 patients were studied in total, 30 received tranexamic acid 10 mg/kg on induction and a further dose shortly before the release of the tourniquet. Surgery was performed by the senior author in a standardised fashion using the Freeman Samuelson cemented total knee replacement. Haemoglobin levels were measured 2 weeks pre and 3 days post operatively. Any complications were noted. A control group was matched using the Bone and Joint Research Unit database for age, sex, disease and pre-operative haemoglobin level. This group had been monitored in the same way as the group treated with tranexamic acid.

RESULTS

In the group receiving no tranexamic acid the mean fall in haemoglobin was 2.8 g/dl (95% CI of mean 2.5-3.2) and in the group treated with tranexamic acid 1.7 g/dl (95% CI of mean 1.3-2) P<0.01. There were no complications in either group.

CONCLUSIONS

The administration of tranexamic acid is an effective method of reducing the haemoglobin fall following knee arthroplasty.

The provision of secondary cardiac prevention measures in a hospital cardiac clinic population and the relationship to psychological variables

BACKGROUND

Implementing preventive measures in patients with established heart disease is one of the most effective health promotion activities, but there is little research on the relationship between cognition and secondary preventive behaviour.

AIM

To determine the provision of secondary cardiac prevention measures among patients with established heart disease attending a cardiac outpatient clinic.

METHODS

The study was conducted in an outpatient department over a 14-week period in 1999. Management of risk markers was noted from the medical records and lifestyle and psychological variables were self-reported.

RESULTS

Of 294 patients with heart disease, 41% were available for study. Fourteen per cent were current smokers, one-quarter of males and one-third of females had a body mass index (BMI) greater that 30. Almost 90% attend their GP bimonthly, 67% had a normal systolic and 88.3% a normal diastolic pressure, 34% had normal cholesterol levels and 75% were on aspirin. Lifestyle variables were significantly affected by patient cardiac knowledge, sense of control over their heart disease and perceptions of their illness.

CONCLUSIONS

These results highlight the potential health gain available to patients with established heart disease. The results also suggest that psychological factors may play a role in patients' health behaviours.

Integrating reproductive health into emergency response assessments and primary health care

War-affected populations often are displaced for years. When primary health care is focused on the acute conditions that often present in the emergency phase of a complex emergency, insufficient attention often is directed towards other evolving needs of the population. Their reproductive health, psychosocial health, and problems with chronic diseases may be overlooked even after the situation stabilizes. This article examines currently available resources for conducting rapid assessments of health needs and services during complex emergencies. Their respective strengths and weaknesses are discussed, particularly for assessing a population's reproductive health needs, and for fostering the integration of reproductive health and primary health-care services, and for designing health services delivery. When more specific indicators are included in a needs assessment tool, the likelihood that the assessment results will influence the design and scope of the health program is increased. Needs assessments for primary health care that incorporate reproductive health indicators will assist health officials to integrate these services, and thus, use staff and facilities more efficiently, and will highlight areas of opportunity for providing services.

Resection of right atrial tumor thrombi without circulatory arrest

Resectable retroperitoneal tumors with right atrial tumor thrombus extension have been excised previously using cardiopulmonary bypass and deep hypothermic circulatory arrest. We have used a technique involving clamping of the descending aorta with avoidance of deep hypothermic circulatory arrest in 6 patients. The approach provided a virtually bloodless field and allowed complete resection to be performed with low morbidity.

Broad specificity of GDNF family receptors GFRalpha1 and GFRalpha2 for GDNF and NTN in neurons and transfected cells

The glial cell line-derived neurotrophic factor (GDNF) family of ligands binds to lipid anchored proteins termed GDNF family receptor (GFR)alphas, and then activates the RET receptor tyrosine kinase, by ligand GFRalpha. The binding of soluble GFRalphas to transfected cells suggested that different GFRalphas were dedicated to particular ligands, with GDNF acting primarily or entirely through GFRalpha1, and neurturin (NTN), through GFRalpha2. More recent evidence has suggested the possibility of cross-talk between these ligands and the two receptors. We examined here whether crosstalk between the GDNF ligands and the GFRalphas is biologically relevant, using midbrain dopaminergic, and parasympathetic, submandibular gland neurons. By biochemical and genetic addition and/or deletion of GFRalpha1 and 2, we show that in both neuronal cell types, robust biological activities of GDNF or NTN can be mediated by either GFRalpha1 or GFRalpha2, although GDNF is slightly more potent in dopaminergic (DA) neurons which normally express GFRalpha1, and NTN in submandibular neurons which normally express GFRalpha2. Throughout the body, GDNF and NTN are likely to have important biological actions on both GFRalpha1- and GFRalpha2-expressing cells.

Glaucoma and race: a case for screening in Connecticut

This study is a review of the current literature regarding the relationship of primary open angle glaucoma and race. There is strong evidence that blacks have a much higher prevalence rate of this disease. They also tend to have a more severe clinical course. Glaucoma is the leading cause of irreversible blindness in blacks. The number of blacks in Connecticut with glaucoma is estimated to be between 14,000 and 21,000, and it is estimated that up to half of these cases are currently undetected. New technology has made screening for glaucoma more practical and cost-effective. This study suggests that glaucoma screening would be beneficial for the black population of Connecticut.

Mice lacking alpha-synuclein display functional deficits in the nigrostriatal dopamine system

alpha-Synuclein (alpha-Syn) is a 14 kDa protein of unknown function that has been implicated in the pathophysiology of Parkinson's disease (PD). Here, we show that alpha-Syn-/- mice are viable and fertile, exhibit intact brain architecture, and possess a normal complement of dopaminergic cell bodies, fibers, and synapses. Nigrostriatal terminals of alpha-Syn-/- mice display a standard pattern of dopamine (DA) discharge and reuptake in response to simple electrical stimulation. However, they exhibit an increased release with paired stimuli that can be mimicked by elevated Ca2+. Concurrent with the altered DA release, alpha-Syn-/- mice display a reduction in striatal DA and an attenuation of DA-dependent locomotor response to amphetamine. These findings support the hypothesis that alpha-Syn is an essential presynaptic, activity-dependent negative regulator of DA neurotransmission.

The seven-transmembrane receptor smoothened cell-autonomously induces multiple ventral cell types

Sonic Hedgehog (Shh) is a secreted protein that controls cell fate and mitogenesis in the developing nervous system. Here we show that a constitutively active form of Smoothened (Smo-M2) mimics concentration-dependent actions of Shh in the developing neural tube, including activation of ventral marker genes (HNF3beta, patched, Nkx2.2, netrin-1), suppression of dorsal markers (Pax-3, Gli-3, Ephrin A5) and induction of ventral neurons (dopaminergic, serotonergic) and ventrolateral motor neurons (Islet-1+, Islet-2+, HB9+) and interneurons (Engrailed-1+, CHX10+). Furthermore, Smo-M2's patterning activities were cell autonomous, occurring exclusively in cells expressing Smo-M2. These findings suggest that Smo is a key signaling component in the Hh receptor and that Shh patterns the vertebrate nervous system as a morphogen, rather than through secondary relay signals.

Signalling by the RET receptor tyrosine kinase and its role in the development of the mammalian enteric nervous system

RET is a member of the receptor tyrosine kinase (RTK) superfamily, which can transduce signalling by glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) in cultured cells. In order to determine whether in addition to being sufficient, RET is also necessary for signalling by these growth factors, we studied the response to GDNF and NTN of primary neuronal cultures (peripheral sensory and central dopaminergic neurons) derived from wild-type and RET-deficient mice. Our experiments show that absence of a functional RET receptor abrogates the biological responses of neuronal cells to both GDNF and NTN. Despite the established role of the RET signal transduction pathway in the development of the mammalian enteric nervous system (ENS), very little is known regarding its cellular mechanism(s) of action. Here, we have studied the effects of GDNF and NTN on cultures of neural crest (NC)-derived cells isolated from the gut of rat embryos. Our findings suggest that GDNF and NTN promote the survival of enteric neurons as well as the survival, proliferation and differentiation of multipotential ENS progenitors present in the gut of E12.5-13.5 rat embryos. However, the effects of these growth factors are stage-specific, since similar ENS cultures established from later stage embryos (E14. 5–15.5), show markedly diminished response to GDNF and NTN. To examine whether the in vitro effects of RET activation reflect the in vivo function(s) of this receptor, the extent of programmed cell death was examined in the gut of wild-type and RET-deficient mouse embryos by TUNEL histochemistry. Our experiments show that a subpopulation of enteric NC undergoes apoptotic cell death specifically in the foregut of embryos lacking the RET receptor. We suggest that normal function of the RET RTK is required in vivo during early stages of ENS histogenesis for the survival of undifferentiated enteric NC and their derivatives.

Specification of dopaminergic and serotonergic neurons in the vertebrate CNS

The early specification of dopaminergic and serotonergic neurons during vertebrate CNS development relies on signals produced by a small number of organizing centers. Recent studies have characterized these early organizing centers, the manner in which they may be established, the inductive signals they produce, and candidate signaling systems that control the later development of the dopaminergic system.

The impact of reminder letters on attendance for breast cancer screening

OBJECTIVE

The aims of this investigation was to analyse the response to second and third postal invitations from a group of patients previously invited for mammographic screening and to identify any demographic differences between responders and non-responders.

SUBJECTS

The subjects were females aged 50-64 yr resident in 6 adjacent District Electoral Divisions (DEDs) in North Dublin where screening had not been carried out prior to the study.

METHOD

Non-responders to an invitation for screening were re-invited by computer-generated letter to attend for screening 6 weeks after issue of the first invitation and a final invitation was issued at 12 weeks. Data sources used for the project register were the Eastern Health Board General Medical Services data base (GMS), Voluntary Health Insurance Board (VHI) data and self-registration.

RESULTS

There were 1,310 females in the target age group who were eligible for screening. The response rate to the first invitation was 60.7 per cent. Issue of second invitation increased the response rate by 17.9 per cent. A third invitation increased the response rate by a further 7.6 per cent. Those with private medical insurance were more likely to respond to the first and third invitations. The was no difference in response rate to the second invitation for those with and without private insurance. Women aged 55-64 were more likely to respond to first, second or third invitations than those aged less than 55 yr.

CONCLUSIONS

Issue of second mailed invitations to women in the target age for mammography screening is cost-effective and should be incorporated into routine policy. Response to third invitations is not cost-effective.

GFRalpha1 is an essential receptor component for GDNF in the developing nervous system and kidney

Glial cell line-derived neurotrophic factor (GDNF) is a distant member of the TGFbeta protein family that is essential for neuronal survival and renal morphogenesis. We show that mice who are deficient in the glycosyl-phosphatidyl inositol (GPI) -linked protein GFRalpha1 (GDNFRalpha) display deficits in the kidneys, the enteric nervous system, and spinal motor and sensory neurons that are strikingly similar to those of the GDNF- and Ret-deficient mice. GFRalpha1-deficient dopaminergic and nodose sensory ganglia neurons no longer respond to GDNF or to the structurally related protein neurturin (NTN) but can be rescued when exposed to GDNF or neurturin in the presence of soluble GFRalpha1. In contrast, GFRalpha1-deficient submandibular parasympathetic neurons retain normal response to these two factors. Taken together with the available genetic and biochemical data, these findings support the idea that GFRalpha1 and the transmembrane tyrosine kinase Ret are both necessary receptor components for GDNF in the developing kidney and nervous system, and that GDNF and neurturin can mediate some of their activities through a second receptor.

Decreased symbiotic effectiveness of Rhizobium leguminosarum strains carrying plasmid RP4

The presence of derivatives of the broad host range plasmid RP4 in strains of Rhizobium leguminosarum biovar viciae severely inhibited nitrogen fixation by these strains in nodules on cultivars of pea (Pisum sativum). The strains formed small white nodules. Yield and total nitrogen values were comparable with those obtained for plants inoculated with a non-nodulating mutant. Strains carrying the same derivatives gave rise to nitrogen fixing nodules when inoculated on cultivars of lentils (Lens culinaris). Similar results were observed with plasmid R702 but not with R751, suggesting that the effect is limited to plasmids of the IncP alpha classification. Histological examination of nodules induced by strains carrying RP4 indicated that there are fewer infected cells and starch granules are organised unusually in the infected cells. Tn5 mutagenesis of plasmid RP4-4 was undertaken and Tn5 inserts were screened for abolition of the effect on nitrogen fixation. Eight mutants, having no effect on nitrogen fixation, were isolated. Seven of these had lost the ability to transfer by conjugation and the eighth was greatly reduced in conjugation frequency. Physical analysis of the transposon inserts revealed that they were located in the Tra regions of RP4.

Feasibility of population based screening in Ireland

Population registers have formed the basis for computerised call/recall registers for screening programmes in many countries and have been important in achieving high uptakes in targeted populations. The absence of a population register for the ECCLES (European Campaign against Cancer, Localisation, Evaluation & Screening) Breast Screening Project necessitated the development of a special register of women in the target age group. The data sources used to build the project register were the Eastern Health Board and North Eastern Health Board General Medical Services database, Voluntary Health Insurance data and self-registration with the project. The register captured 86.3 per cent of the target population. A debate on the merits and difficulties associated with the setting up of a population register in Ireland is now timely.

Persephin, a novel neurotrophic factor related to GDNF and neurturin

A novel neurotrophic factor named Persephin that is approximately 40% identical to glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) has been identified using degenerate PCR. Persephin, like GDNF and NTN, promotes the survival of ventral midbrain dopaminergic neurons in culture and prevents their degeneration after 6-hydroxydopamine treatment in vivo. Persephin also supports the survival of motor neurons in culture and in vivo after sciatic nerve axotomy and, like GDNF, promotes ureteric bud branching. However, in contrast to GDNF and NTN, persephin does not support any of the peripheral neurons that were examined. Fibroblasts transfected with Ret and one of the coreceptors GFRalpha-1 or GFRalpha-2 do not respond to persephin, suggesting that persephin utilizes additional, or different, receptor components than GDNF and NTN.

Activating Smoothened mutations in sporadic basal-cell carcinoma

Basal-cell carcinomas (BCCs) are the commonest human cancer. Insight into their genesis came from identification of mutations in the PATCHED gene (PTCH) in patients with the basal-cell nevus syndrome, a hereditary disease characterized by multiple BCCs and by developmental abnormalities. The binding of Sonic hedgehog (SHH) to its receptor, PTCH, is thought to prevent normal inhibition by PTCH of Smoothened (SMO), a seven-span transmembrane protein. According to this model, the inhibition of SMO signalling is relieved following mutational inactivation of PTCH in basal-cell nevus syndrome. We report here the identification of activating somatic missense mutations in the SMO gene itself in sporadic BCCs from three patients. Mutant SMO, unlike wild type, can cooperate with adenovirus E1A to transform rat embryonic fibroblast cells in culture. Furthermore, skin abnormalities similar to BCCs developed in transgenic murine skin overexpressing mutant SMO. These findings support the role of SMO as a signalling component of the SHH-receptor complex and provide direct evidence that mutated SMO can function as an oncogene in BCCs.

Control of cell pattern in the neural tube by the zinc finger transcription factor and oncogene Gli-1

Sonic hedgehog (Shh) is a putative morphogen secreted by the floor plate and notochord, which specifies the fate of multiple cell types in the ventral aspect of the vertebrate nervous system. Since in Drosophila the actions of Hh have been shown to be transduced by Cubitus interruptus (Ci), a zinc finger transcription factor, we examined whether a vertebrate homolog of this protein can mediate the functions of Shh in the vertebrate nervous system. Here, we demonstrate that expression of Gli-1, one of three vertebrate homologs of Ci, can be induced by Shh in the neural tube. Further, ectopic expression of Gli-1 in the dorsal midbrain and hindbrain of transgenic mice mimics the effects of ectopically expressed Shh-N, leading to the activation of ventral neural tube markers such as Ptc, HNF-3beta, and Shh; to the suppression of dorsal markers such as Pax-3 and AL-1; and to the formation of ectopic dorsal clusters of dopaminergic and serotonergic neurons. These findings demonstrate that GLI-1 can reproduce the cell patterning actions of Shh in the developing nervous system and provide support for the hypothesis that it is a mediator of the Shh signal in vertebrates.