tRNA modification enzyme-dependent redox homeostasis regulates synapse formation and memory

Post-transcriptional modification of RNA regulates gene expression at multiple levels. ALKBH8 is a tRNA modifying enzyme that methylates wobble uridines in specific tRNAs to modulate translation. Through methylation of tRNA-selenocysteine, ALKBH8 promotes selenoprotein synthesis and regulates redox homeostasis. Pathogenic variants in ALKBH8 have been linked to intellectual disability disorders in the human population, but the role of ALKBH8 in the nervous system is unknown. Through in vivo studies in Drosophila , we show that ALKBH8 controls oxidative stress in the brain to restrain synaptic growth and support learning and memory. ALKBH8 null animals lack wobble uridine methylation and exhibit a global reduction in protein synthesis, including a specific decrease in selenoprotein levels. Loss of ALKBH8 or independent disruption of selenoprotein synthesis results in ectopic synapse formation. Genetic expression of antioxidant enzymes fully suppresses synaptic overgrowth in ALKBH8 null animals, confirming oxidative stress as the underlying cause of dysregulation. ALKBH8 animals also exhibit associative learning and memory impairments that are reversed by pharmacological antioxidant treatment. Together, these findings demonstrate the critical role of tRNA modification in redox homeostasis in the nervous system and reveal antioxidants as a potential therapy for ALKBH8-associated intellectual disability.

Significance Statement

tRNA modifying enzymes are emerging as important regulators of nervous system development and function due to their growing links to neurological disorders. Yet, their roles in the nervous system remain largely elusive. Through in vivo studies in Drosophila , we link tRNA methyltransferase-regulated selenoprotein synthesis to synapse development and associative memory. These findings demonstrate the key role of tRNA modifiers in redox homeostasis during nervous system development and highlight the potential therapeutic benefit of antioxidant-based therapies for cognitive disorders linked to dysregulation of tRNA modification.

Combining ability and heterosis studies for grain iron and zinc concentrations in pearl millet [Cenchrus americanus (L). Morrone]

Iron (Fe) and zinc (Zn) deficiency has been identified as a major food-related health issue, affecting two billion people globally. Efforts to enhance the Fe and Zn content in food grains through plant breeding are an economic and sustainable solution to combat micronutrient deficiency in resource-poor populace of Asia and Africa. Pearl millet, Cenchrus americanus (L). Morrone, considered as a hardy nutri-cereal, is the major food crop for millions of people of these nations. As an effort to enhance its grain mineral content, an investigation was conducted using line × tester analysis to generate information on the extent of heterosis, gene action, combining ability for grain yield potential, and grain mineral nutrients (Fe and Zn). The partitioning of variance attributable to parents indicated that the lines and testers differed significantly for the traits studied. For most of the attributes, hybrids that were superior to the parents in the desired direction in terms of per se performance were identified. The analysis of combining ability variance indicated the preponderance of both additive and non-additive genetic effects. Thus, reciprocal recurrent selection can be used to develop a population with high-grain Fe and Zn contents. The Fe and Zn content in grain exhibited a highly significant and positive association between them, whereas the Fe and Zn contents individually showed a negative, albeit weak, correlation with grain yield and a moderate positive relation with grain weight. This indicates that mineral nutrient contents in grains can be improved without significant compromise on yield. The consistency of these trends across the environment suggests that these findings could be directly used as guiding principles for the genetic enhancement of Fe and Zn grain content in pearl millet.

Achieving nutritional security in India through iron and zinc biofortification in pearl millet (Pennisetum glaucum (L.) R. Br.)

The health problems caused by iron (Fe) and zinc (Zn) deficiency plague developing and underdeveloped countries. A vegetarian person mainly depends on cereal based diet with low quantity of Fe and Zn. Biofortification is an economical and sustainable approach to challenge the micronutrient malnutrition problem globally. Pearl millet (Pennisetum glaucum (L.) R. Br.) is one of the nutri-cereals and mostly grown under hot, dry conditions on infertile soils of low water-holding capacity, where other crops generally fail. It contains anti-nutrient compounds like phytic acid and polyphenols which reduce the mineral bioavailability because of their chelating properties. Biofortification of pearl millet is like a double-edged sword which cuts down the economic burden and simultaneously supplies required nutrition to the poor, offering a great scope for food security as well as nutritional security. With this background, this review focus on biofortification of grain Fe and Zn content in pearl millet. Genetic research on Fe and Zn uptake and accumulation in pearl millet grain is crucial in identifying the 'bottlenecks' in biofortification. The review also reveals the need and strategies for increasing bioavailability of Fe and Zn in humans by increasing promoters and decreasing anti-nutritional factors in pearl millet.

tRNA overexpression rescues peripheral neuropathy caused by mutations in tRNA synthetase

[Figure: see text].

Multi-Environment Quantitative Trait Loci Mapping for Grain Iron and Zinc Content Using Bi-parental Recombinant Inbred Line Mapping Population in Pearl Millet

Pearl millet is a climate-resilient, nutritious crop with low input requirements that could provide economic returns in marginal agro-ecologies. In this study, we report quantitative trait loci (QTLs) for iron (Fe) and zinc (Zn) content from three distinct production environments. We generated a genetic linkage map using 210 F₆ recombinant inbred line (RIL) population derived from the (PPMI 683 × PPMI 627) cross using genome-wide simple sequence repeats (SSRs). The molecular linkage map (seven linkage groups) of 151 loci was 3,273.1 cM length (Kosambi). The content of grain Fe in the RIL population ranged between 36 and 114 mg/Kg, and that of Zn from 20 to 106 mg/Kg across the 3 years (2014-2016) at over the three locations (Delhi, Dharwad, and Jodhpur). QTL analysis revealed a total of 22 QTLs for grain Fe and Zn, of which 14 were for Fe and eight were for Zn on three consecutive years at all locations. The observed phenotypic variance (R ²) explained by different QTLs for grain Fe and Zn content ranged from 2.85 (QGFe.E3.2014-2016_Q3) to 19.66% (QGFe.E1.2014-2016_Q3) and from 2.93 (QGZn.E3.2014-2016_Q3) to 25. 95% (QGZn.E1.2014-2016_Q1), respectively. Two constitutive expressing QTLs for both Fe and Zn co-mapped in this population, one on LG 2 and second one on LG 3. Inside the QTLs candidate genes such as Ferritin gene, Al³⁺ Transporter, K⁺ Transporters, Zn²⁺ transporters and Mg²⁺ transporters were identified using bioinformatics approaches. The identified QTLs and candidate genes could be useful in pearl millet population improvement programs, seed, restorer parents, and marker-assisted selection programs.

The Drosophila FUS ortholog cabeza promotes adult founder myoblast selection by Xrp1-dependent regulation of FGF signaling

The number of adult myofibers in Drosophila is determined by the number of founder myoblasts selected from a myoblast pool, a process governed by fibroblast growth factor (FGF) signaling. Here, we show that loss of cabeza (caz) function results in a reduced number of adult founder myoblasts, leading to a reduced number and misorientation of adult dorsal abdominal muscles. Genetic experiments revealed that loss of caz function in both adult myoblasts and neurons contributes to caz mutant muscle phenotypes. Selective overexpression of the FGF receptor Htl or the FGF receptor-specific signaling molecule Stumps in adult myoblasts partially rescued caz mutant muscle phenotypes, and Stumps levels were reduced in caz mutant founder myoblasts, indicating FGF pathway deregulation. In both adult myoblasts and neurons, caz mutant muscle phenotypes were mediated by increased expression levels of Xrp1, a DNA-binding protein involved in gene expression regulation. Xrp1-induced phenotypes were dependent on the DNA-binding capacity of its AT-hook motif, and increased Xrp1 levels in founder myoblasts reduced Stumps expression. Thus, control of Xrp1 expression by Caz is required for regulation of Stumps expression in founder myoblasts, resulting in correct founder myoblast selection.

FUS-mediated regulation of acetylcholine receptor transcription at neuromuscular junctions is compromised in amyotrophic lateral sclerosis

Neuromuscular junction (NMJ) disruption is an early pathogenic event in amyotrophic lateral sclerosis (ALS). Yet, direct links between NMJ pathways and ALS-associated genes such as FUS, whose heterozygous mutations cause aggressive forms of ALS, remain elusive. In a knock-in Fus-ALS mouse model, we identified postsynaptic NMJ defects in newborn homozygous mutants, attributable to mutant FUS toxicity in skeletal muscle. Adult heterozygous knock-in mice displayed smaller neuromuscular endplates that denervated before motor neuron loss, consistent with ‘dying-back’ neuronopathy. FUS was enriched in subsynaptic myonuclei, and this innervation-dependent enrichment was distorted in FUS-ALS. Mechanistically, FUS collaborates with the ETS-transcription factor ERM to stimulate transcription of acetylcholine receptor (AchR) genes. FUS-ALS patient iPSC-derived motor neuron-myotube co-cultures revealed endplate maturation defects due to intrinsic FUS toxicity in both motor neurons and myotubes. Thus, FUS regulates AChR gene expression in subsynaptic myonuclei and muscle-intrinsic toxicity of ALS-mutant FUS may contribute to dying-back motor neuronopathy.

Xrp1 genetically interacts with the ALS-associated FUS orthologue caz and mediates its toxicity

Mallik et al. identify Xrp1 as a nuclear chromatin-binding protein involved in gene expression regulation that mediates phenotypes induced by loss of function of cabeza (caz), the Drosophila melanogaster orthologue of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) protein FUS. Knockdown of Xrp1 in motor neurons rescues phenotypes induced by ALS-mutant FUS.

Cabeza (caz) is the single Drosophila melanogaster orthologue of the human FET proteins FUS, TAF15, and EWSR1, which have been implicated in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. In this study, we identified Xrp1, a nuclear chromatin-binding protein, as a key modifier of caz mutant phenotypes. Xrp1 expression was strongly up-regulated in caz mutants, and Xrp1 heterozygosity rescued their motor defects and life span. Interestingly, selective neuronal Xrp1 knockdown was sufficient to rescue, and neuronal Xrp1 overexpression phenocopied caz mutant phenotypes. The caz/Xrp1 genetic interaction depended on the functionality of the AT-hook DNA-binding domain in Xrp1, and the majority of Xrp1-interacting proteins are involved in gene expression regulation. Consistently, caz mutants displayed gene expression dysregulation, which was mitigated by Xrp1 heterozygosity. Finally, Xrp1 knockdown substantially rescued the motor deficits and life span of flies expressing ALS mutant FUS in motor neurons, implicating gene expression dysregulation in ALS-FUS pathogenesis.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Correlation of Computed Tomography findings with Glasgow Coma Scale in patients with acute traumatic brain injury

OBJECTIVE To correlate Computed Tomography (CT) findings with Glasgow Coma Scale (GCS) in patients with acute traumatic brain injury attending in Chitwan Medical College teaching hospital Chitwan, Nepal.MATERIALS AND METHODS A cross-sectional study was performed among 50 patients of acute (less than24 hours) cases of craniocerebral trauma over a period of four months. The patient’s level of consciousness (GCS) was determined and a brain CT scan without contrast media was performed. A sixth generation General Electric (GE) CT scan was utilized and 5mm and 10mm sections were obtained for infratentorial and supratentorial parts respectively.RESULT The age range of the patients was 1 to 75 years (mean age 35.6± 21.516 years) and male: female ratio was 3.1:1. The most common causes of head injury were road traffic accident (RTA) (60%), fall injury (20%), physical assault (12%) and pedestrian injuries (8%). The distribution of patients in accordance with consciousness level was found to be 54% with mild TBI (GCS score 12 to 14), 28% with moderate TBI (GCS score 11 to 8) and 18% with severe TBI (GCS score less than 7). The presence of mixed lesions and midline shift regardless of the underlying lesion on CT scan was accompanied by lower GCS.CONCLUSION The presence of mixed lesions and midline shift regardless of the underlying lesion on CT scan were accompanied with lower GCS. Patients having single lesion had more GCS level than mixed level and mid line shift type of injury.Journal of College of Medical Sciences-Nepal, 2014, Vol.10(2); 4-9

Highly efficient cell-type-specific gene inactivation reveals a key function for the Drosophila FUS homolog cabeza in neurons

To expand the rich genetic toolkit of Drosophila melanogaster, we evaluated whether introducing FRT or LoxP sites in endogenous genes could allow for cell-type-specific gene inactivation in both dividing and postmitotic cells by GAL4-driven expression of FLP or Cre recombinase. For proof of principle, conditional alleles were generated for cabeza (caz), the Drosophila homolog of human FUS, a gene implicated in the neurodegenerative disorders amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Upon selective expression in neurons or muscle, both FLP and Cre mediated caz inactivation in all neurons or muscle cells, respectively. Neuron-selective caz inactivation resulted in failure of pharate adult flies to eclose from the pupal case, and adult escapers displayed motor performance defects and reduced life span. Due to Cre-toxicity, FLP/FRT is the preferred system for cell-type-specific gene inactivation, and this strategy outperforms RNAi-mediated knock-down. Furthermore, the GAL80 target system allowed for temporal control over gene inactivation, as induction of FLP expression from the adult stage onwards still inactivated caz in >99% of neurons. Remarkably, selective caz inactivation in adult neurons did not affect motor performance and life span, indicating that neuronal caz is required during development, but not for maintenance of adult neuronal function.

The changing face of donation in the UK: kidney donation after circulatory death

Affiliated to the Association of Surgeons in Training and the British Transplantation Society, the Carrel Club is the transplant trainee surgical society. The Carrel Club held a joint meeting with the Chapter of Transplant Surgeons, a subsidiary organisation of the British Transplantation Society, at the Manchester Hilton Hotel on 31 January and 1 February 2013. As part of the meeting, ten abstracts were presented. A selection is printed below. The winner of the Best Presentation award was Mr Mownah.

Comparison of liver transplantation outcomes from adult split liver and circulatory death donors

BACKGROUND

Adult whole-organ donation after circulatory death (DCD) and 'split' extended right lobe donation after brain death (ERL-DBD) liver transplants are considered marginal, but direct comparison of outcomes has rarely been performed. Such a comparison may rationalize the use of DCD livers, which varies widely between UK centres.

METHODS

Outcomes for adult ERL-DBD livers and 'controlled' DCD liver transplantations performed at the Cambridge Transplant Centre between January 2004 and December 2010 were compared retrospectively.

RESULTS

None of the 32 patients in the DCD cohort suffered early graft failure, compared with five of 17 in the ERL-DBD cohort. Reasons for graft failure were hepatic artery thrombosis (3), progressive cholestasis (1) and small-for-size syndrome (1). Early allograft dysfunction occurred in a further five patients in each group. In the DCD group, ischaemic cholangiopathy developed in six patients, resulting in graft failure within the first year in two; the others remained stable. The incidence of biliary anastomotic complications was similar in both groups. Kaplan-Meier survival analysis confirmed superior graft survival in the DCD liver group (93 per cent at 3 years versus 71 per cent in the ERL-DBD cohort; P = 0·047), comparable to that of contemporaneous whole DBD liver transplants (93 per cent at 3 years). Patient survival was similar in all groups.

CONCLUSION

Graft outcomes of DCD liver transplants were better than those of ERL-DBD liver transplants. Redefining DCD liver criteria and refining donor-recipient selection for ERL-DBD transplants should be further explored.

The ISWI chromatin remodeler organizes the hsrω ncRNA-containing omega speckle nuclear compartments

The complexity in composition and function of the eukaryotic nucleus is achieved through its organization in specialized nuclear compartments. The Drosophila chromatin remodeling ATPase ISWI plays evolutionarily conserved roles in chromatin organization. Interestingly, ISWI genetically interacts with the hsrω gene, encoding multiple non-coding RNAs (ncRNA) essential, among other functions, for the assembly and organization of the omega speckles. The nucleoplasmic omega speckles play important functions in RNA metabolism, in normal and stressed cells, by regulating availability of hnRNPs and some other RNA processing proteins. Chromatin remodelers, as well as nuclear speckles and their associated ncRNAs, are emerging as important components of gene regulatory networks, although their functional connections have remained poorly defined. Here we provide multiple lines of evidence showing that the hsrω ncRNA interacts in vivo and in vitro with ISWI, regulating its ATPase activity. Remarkably, we found that the organization of nucleoplasmic omega speckles depends on ISWI function. Our findings highlight a novel role for chromatin remodelers in organization of nucleoplasmic compartments, providing the first example of interaction between an ATP-dependent chromatin remodeler and a large ncRNA.

Chromatin structure and function are regulated by the concerted activity of covalent modifiers of chromatin, nucleosome remodeling factors, and several emerging classes of non-coding RNAs. ISWI is an evolutionarily conserved ATP-dependent chromatin remodeler playing essential roles in chromosome condensation, gene expression, and DNA replication. ISWI activity has been involved in a variety of nuclear functions including telomere silencing, stem cell renewal, neural morphogenesis, and epigenetic reprogramming. Using an in vivo assay to identify factors regulating ISWI activity in the model system Drosophila melanogaster, we recovered a genetic interaction between ISWI and hsrω. The hsrω gene encodes multiple non-coding RNAs (ncRNAs), of which the >10 kb nuclear hsrω-n RNA, with functional homolog in mammals, is essential for the assembly and organization of hnRNP-containing nucleoplasmic omega speckles. These special nuclear compartments play essential roles in the storage/sequestration of hnRNP family and other proteins, thus playing important roles in mRNA maturation and other regulatory processes. Here we show that the hsrω-n ncRNA interacts in vivo and in vitro with ISWI to directly regulate its ATPase activity. We also provide in vivo data showing that omega speckle nuclear organization depends on ISWI function, highlighting a novel role for chromatin remodelers in nuclear speckles organization.

Lessons from Fruit Fly Models for PolyQ Neurodegenerative Disorders

Polyglutamine (polyQ) diseases, resulting from a dynamic expansion of glutamine repeats in a polypeptide, are a class of genetically inherited, late-onset neurodegenerative disorders which, despite wide expression of the mutated gene in brain and other tissues, affect defined subpopulations of neurons in a disease-specific manner. This presentation will review the advantages of modelling these neurodegenerative diseases in Drosophila, and the insights obtained. Studies with the fruit fly models have successfully identified a variety of genetic modifiers, and have helped to further our understanding of some of the molecular events that follow expression of the abnormal polyQ proteins. Expression of the mutant polyQ proteins causes, as a consequence of intra-cellular and inter-cellular networking, mis-regulation in the sensitive neurons at multiple points, such as during transcriptional regulation, post-transcriptional regulation, cell signalling, protein quality control (protein folding and degradation networks), and axonal transport, resulting ultimately in cell death. The diversity of genetic modifiers of polyQ toxicity, identified through extensive genetic screening in the fruit fly and in other models, clearly reflects a complex network effect of the presence of the mutated protein. Such a network effect poses a major challenge for therapeutic applications.

Heat shock genes - integrating cell survival and death

Heat shock induced gene expression and other cellular responses help limit the damage caused by stress and thus facilitate cellular recovery. Cellular damage also triggers apoptotic cell death through several pathways. This paper briefly reviews interactions of the major heat shock proteins with components of the apoptotic pathways. Hsp90, which acts as a chaperone for unstable signal transducers to keep them poised for activation, interacts with RIP and Akt and promotes NF-kappa B mediated inhibition of apoptosis; in addition it also blocks some steps in the apoptotic pathways. Hsp70 is mostly anti-apoptotic and acts at several levels like inhibition of translocation of Bax into mitochondria, release of cytochrome c from mitochondria,formation of apoptosome and inhibition of activation of initiator caspases. Hsp70 also modulates JNK,NF-kappa B and Akt signaling pathways in the apoptotic cascade. In contrast, Hsp60 has both anti-and pro-apoptotic roles. Cytosolic Hsp60 prevents translocation of the pro-apoptotic protein Bax into mitochondria and thus promotes cell survival but it also promotes maturation of procaspase-3,essential for caspase mediated cell death. Our recent in vivo studies show that RNAi for the Hsp60D in Drosophila melanogaster prevents induced apoptosis. Hsp27 exerts its anti-apoptotic influence by inhibiting cytochrome c and TNF-mediated cell death. alpha beta crystallin suppresses caspase-8 and cytochrome c mediated activation of caspase-3. Studies in our laboratory also reveal that absence or reduced levels of the developmentally active as well as stress induced non-coding hsr omega transcripts, which are known to sequester diverse hnRNPs and related nuclear RNA-binding proteins,block induced apoptosis in Drosophila. Modulation of the apoptotic pathways by Hsps reflects their roles as "weak links" between various "hubs" in cellular networks. On the other hand, non-coding RNAs, by virtue of their potential to bind with multiple proteins,can act as "hubs" in these networks. In view of the integrative nature of living systems, it is not surprising that stress-induced genes,generally believed to primarily function in cell survival pathways, inhibit or even promote cell death pathways at multiple levels to ensure homeostasis at cell and/or organism level. The heat shock genes obviously do much more than merely help cells survive stress.

Diffusion of the concept of patient advocacy

PURPOSE

To examine the growth and diffusion through the USA and UK literature of nurses claims to patient advocacy.

DESIGN

A bibliometric analysis of articles cited under the key descriptor "patient advocacy" in the International Nursing Index (INI) was undertaken. Analysis included output in 5-year accumulations from 1976 to 1995, and was focused on quantity of output and exposition of concerns through interpretation of the titles. Citation mapping was undertaken to trace dominant influences in the diffusion process.

METHODS

Titles and countries of origin of the journal along with year of publication were organized into a database to provide quantitative material on comparative output from the USA and the UK. Citation profiles of key influencing authors were examined.

FINDINGS

A role in patient advocacy was proposed in the American nursing literature in the late 1970s and in the British literature a decade later. Support for the role was evident in its use in professional organizations and schools. The pattern of dissemination illustrates the influence of American nursing on the professional role of nurses in the UK.

CONCLUSIONS

On the basis of a stages model for diffusion of an innovation, patient advocacy has reached only preliminary stages of acceptance as an innovation in nursing.

An exploration into the role of the teacher/lecturer in practice: findings from a case study in adult nursing

Against a background of increasing concern over the widening theory practice gap and research evidence of problems in providing quality practice education, the English National Board (ENB) commissioned an 18 month study into the role of the teacher/lecturer in practice. This article, after providing a brief overview of the background, literature and methods, outlines the results from the Adult Case Study stage of the research. Documents, individual and focus group interviews of lecturers (n = 76), practitioners (n = 46) and students (n = 131) in five schools of nursing and midwifery provided data for analysis. A role labeled as 'link lecturer' was the most common approach acknowledged by all respondent groups. Despite overt commitment to the practice role by schools of nursing and midwifery, findings indicate that lecturers are unprepared, unsupported and unmonitored. Students and practitioners had very variable experiences and expressed a strong need for a better-organized approach which would provide them with consistent and sustained support in the practice setting. Overall the study highlighted a lack of strategic management of the practice role by university schools of nursing and midwifery. Convergence of findings from midwifery and the other branches of nursing provides strong research evidence for recommendations for more active management of the practice curriculum to be implemented as part of any future proposed reforms for nurse education in the UK.

Advocacy in nursing: perceptions and attitudes of the nursing elite in the United Kingdom

In recent years, patient advocacy has been claimed as an integral part of the nurse's role in health care delivery in the United Kingdom (UK). Support from the nursing leadership/elite is seen as important in the promulgation and diffusion of any 'new' role in nursing. This paper explores the perceptions and attitudes of nurse leaders in the UK to the adoption of the patient advocate role as an 'innovation' in nursing. Using a qualitative methodology, semi-structured interviews with six of nursing's 'elite' were conducted over a period of 5 months. Results revealed contradictions and paradoxes within the views of the elite. Although leaders recognized patient advocacy as a role integral to the moral value system in nursing enhanced by the nurse-patient relationship, they objected to the professionalization of the role, seeing an exclusive claim to patient advocacy as intensifying interprofessional conflicts in health care. It is argued that unless professionalized, the individual nurse will continue this potentially risky activity without adequate authority or support systems. The results overall question the role of the nursing leadership in the diffusion of innovations in nursing.

A comparative study of differences in the referral behaviour patterns of men and women who have experienced cardiac-related chest pain

Survival and long-term prognosis after a myocardial infarction are directly related to the individuals's decision to seek medical help. Early medical intervention is imperative if thrombolytic therapy is to be effective. Emerging research has indicated that women frequently have longer pre-hospital delays than men. Incorporating a comparative descriptive design, this research compared the pre-hospital admission behaviour patterns of women and men, following the onset of acute chest pain. A convenience sample of 12 women and 12 men were selected following admission to a local coronary care unit. Structured interviews and the examination of medical notes/relevant documentation provided the data. Findings were examined and compared through the use of content analysis and descriptive statistics. Severity of symptoms proved to be the strongest influence in shortening pre-hospital delay. Despite this, overall, men were admitted to hospital more quickly than women. Men were more ready than women to believe that they might be having a heart attack and this belief led them to seek treatment promptly. In order to improve female mortality and morbidity following a myocardial infarction, it is recommended that there is an urgent need to target women, through health promotion and media interventions.

Role extension or expansion: a qualitative investigation of the perceptions of senior medical and nursing staff in an adult intensive care unit

The Scope of Professional Practice (UKCC 1992) has significantly altered the interpretation of nurses' roles, emphasizing individual professional accountability and clinical decision-making. However, 5 years after the issue of the document, uncertainties remain regarding interprofessional legal accountability between medicine and nursing. To investigate issues surrounding role extension or expansion in intensive care nursing, a small qualitative study was conducted centred on one intensive care unit (ICU) within a large teaching hospital. Data were collected by semi-structured interviews from a purposive sample of five senior intensive care nurses and three consultant anaesthetists. Four major categories emerged, identified as: interpretation confusion; education for change; struggles for power and task versus autonomy. The findings revealed that the senior critical care nurses identified themselves as independent, autonomous practitioners involved in clinical decision-making. However, there was evidence of a reluctance to empower more junior staff to perform extended or expanded roles. Medical respondents viewed extended or expanded roles as taking on mechanical tasks for which anyone could be trained to perform. In conclusion, it is argued that although nursing is maturing in its growth towards professionalization, broader issues such as the legal quagmire, failure to adopt the philosophy of role expansion and the existence of sacred boundaries intra- and inter-professionally need to be addressed.

The role of nurse educators in the development of reflective practitioners: a selective case study of the Australian and UK experience

The potential to improve patient/client care, stimulate the personal and professional growth of the practitioner and help close the theory practice gap has provoked much discussion in the nursing literature on the benefits of reflection on practice. In order to examine recent developments in this area, a study tour, supported by the Florence Nightingale Foundation, was conducted in Australia and the UK during the spring and summer of 1995. Using an illuminative case study approach, data collected demonstrated that although reflective practice was fully endorsed by the nursing profession in Australia, and there were excellent examples of reflective practice in use, the continued growth of the reflective practice movement appeared to be threatened by the rationalization of both clinical and theoretical education in the universities. Issues around methods of encouraging reflection in students focused on ethical use of journals, the levels of reflection developed and the outcome effectiveness of reflective learning. Although it is recommended that the nursing profession continue to endorse developments in reflective practice in the UK, it is also necessary to encourage both process and outcome evaluations of its effects on the development of the individual nurse and on the ensuing quality of health care delivery.

Advocacy in nursing--perceptions of practising nurses

This paper reports on a qualitative study which examined the interpretation of patient advocacy by practising nurses. Focus group interviews, which allowed respondents to recount and share their particular 'stories' of patient advocacy, were used to collect data. Results indicate that a triadic model of advocacy predominated which involved the nurse in a conflict/potential conflict situation. The patient's requests, the patient's fear, the patient's vulnerability or threats to the patient's human rights provoked an advocacy response in the perceptive nurse. The nurse was sustained in the role through patient recognition, the nurse-patient relationship, emotional strength, moral justification and knowledge/expertise legitimacy. The nurse used direct and indirect means to protect the patient against incompetent/inappropriate practice and/or represent patient/family choice, the advocacy activity resulting in positive or negative outcomes. In conclusion it is argued that if the triadic conflict model of advocacy outlined by this research is to be sustained by practising nurses, the potential risks involved should be recognized. Professionalization of the role may be the only way forward if the ethical code (United Kingdom Central Council, 1992) continues to make patient advocacy a mandatory activity for the professional nurse.

Patient representatives: a new role in patient advocacy

Patient representatives advocate the consumer interests of hospital patients. The initiation and development of this role in hospitals in the USA during the mid-1970s is now being mirrored in the UK. Patient representatives in both countries have been supported by powerful hospital associations, receive their authority to act through hospital management and deal with similar patient issues. Occupational boundary disputes have occurred with other healthcare professionals who feel that they are the patient's advocate. It is important to differentiate between this new full-time professional role and other claims to patient advocacy made by the nursing profession.

Advocacy in nursing--a review of the literature

Patient/client advocacy has been claimed as a new role for the professional nurse. This paper presents a critical review of the literature on advocacy in nursing. After briefly outlining the conditions which may have instigated the need for patient advocacy, meanings and models of advocacy are discussed. It is argued that although there are many examples of the advocacy role in health care, models proposed for the nurse as advocate are indeterminate which leads to multiple interpretations and lack of clarity in operationalizing advocacy. Much of the literature focuses on justification arguments for claiming the advocacy role. Key themes are outlined and include: patient advocacy as a traditional role, nurses are in the best position in the health care team, nurses have the knowledge to advocate and finally nurses and patients can be partners in advocacy. However, critical examination reveals many counter-arguments to the above claims and finally concludes that advocacy is a potentially risky role to adopt. It is argued that support systems are inadequate except in low-risk situations and ultimately acts of advocacy remain a moral choice for the individual nurse. Finally the need to conduct research into the interpretation of the patient advocate role by nurses in the United Kingdom is highlighted.

Real-time sensing of tooth position for dental digital subtraction radiography

Dental digital subtraction radiography requires accurate repositioning of the patient and X-ray source in order to facilitate correct diagnostic of bone loss. Present mechanical repositioning systems do not allow radiography of posterior teeth, and are uncomfortable for the patient. A new repositioning system that utilizes a six degrees of freedom position sensor and a robot arm with X-ray source is proposed. A mathematical model for the system is given, and the robot arm solution is obtained based on patient position. An error analysis is performed in order to determine the influence of sensor and robot errors on system accuracy. A series of experiments to determine sensor noise and accuracy are described. These tests showed relatively small errors over the work envelope of the sensor. Further tests showed that there is no adverse effect due to the presence of metal work in the patient's mouth. The high bandwidth of the sensor may allow real time tracking of small movements of the patient's head.