bluuebunny/crossref_metadata_2025 huggingface dataset:
Does being in the military affect nurses’ perceptions of work life?
Authors: Robinson Sharon E , Rodriguez Ester R , Sammons Lt Morgan T , Keim Jeanmane
Published: July 2003

This study was a causal comparative investigation of military and civilian nurses’ perceptions of selected aspects of work life The Work Environment Scale, the Maslach Burnout Inventory and the Michigan Job Satisfaction Scale were administered to civilian and military samples matched on selected demographic variables MANOVA procedures failed to reveal significant differences on measures of burnout and morale Although military nurses were significantly more satisfied with issues of pay and fringe benefits, civilian nurses reported significantly greater job satisfaction, peer cohesion, supervisory support, decision making, autonomy, task orientation and opportunity to be innovative These findings and suggested changes are discussed with attention to differences between the military and civilian work setting
Inter‐rater reliability of Monitor, Senior Monitor and Qualpacs*
Authors: Tomalin Deborah A , Oliver Sarah , Redfern Sally J , Norman Ian J
Published: July 2003

This paper describes inter‐rater reliability of three quality assessment instruments Monitor, Senior Monitor and Qualpacs The work forms part of a Department of Health funded study examining the reliability and validity of these three instruments Inter‐rater reliability is not a fixed entity and therefore should be tested every time raters or the setting change In this instance, testing was earned out in three wards (one elderly and two surgical) Two methods of analysis were used percent agreement and intra‐class correlation coefficient Results and some of the techniques that were found to be useful in enhancing reliability are described Acceptable levels of inter‐rater reliability with all three instruments were reached
Reflective practice: a critique of the work of Argyris and Schön
Authors: Greenwood Jennifer
Published: July 2003

The seminal work of Argyris and Schon on action theories, technical rationality and reflective practice is reviewed, it is argued that their work reflects important inconsistencies between their theorizing and the pedagogical interventions they implemented/recommended The implications of the results of these inconsistencies, which appear mirrored in nurse‐education programmes in the United Kingdom and Australia, are discussed Tentative suggestions for the provision of a more adequate practical pedagogy are included
School nursing: history, present practice and possibilities reviewed
Authors: While Alison E , Barnball K Louise
Published: July 2003

A review of the literature revealed that the early school nurses were engaged in predominantly screening work and as assistants to the school medical officer The relatively limited empirical work suggests that they have the potential to make a major contribution to the health of school children, however, their current role appears to vary enormously nationwide and the issues of competency for the role and integration into the school team need addressing The consumer/outsider view literature indicated a mismatch between expectations and service provision
Nurses’ provision of teaching and counselling on sexuality: a review of the literature
Authors: Gamel Claudia , Davis Bryn D , Hengeveld Michiel
Published: July 2003

Patients’ sexual concerns and problems are a focus for nursing care Research studies with nurses, patients and healthy adults support this assertion However, investigations also identify that specific teaching, supporting and/or counselling interventions aimed at managing the effects of illness and treatment on sexual function are not provided most of the time This discrepancy can be analysed by exploring factors that influence the nursing care behaviours sex teaching and counselling Investigators have studied the influence of the following five factors (sexuality) knowledge and skills, attitude towards sexuality, opinion about professional role and tasks, comfort with sexuality, and participation in continuing education activities Conflicting findings regarding the influence of these five factors upon teaching and counselling on sexuality are found Predicated upon previous investigations, two specific areas for future investigations are identified First is the need to clarify the definition and theoretical basis for the interventions of teaching and counselling on sexuality Second, future investigations could place the problem within the context of theory which helps to explain (nursing) behaviour, such as the Theory of Reasoned Action
Young adult women: lifestyle and health locus of control
Authors: Schank Mary Jane , Lawrence Donna M
Published: July 2003

A study of 76 young adult women, 38 nursing students and 38 non‐nursing students, examined their lifestyle practices and health locus of control (HLOC) Findings revealed a significant difference between reported lifestyle practices and the career choice of these young adult women The lifestyle practice areas in which the most notable differences occurred included use of seat belts, frequency of alcohol use, frequency of junk food intake, use of illegal drugs and hours of sleep per night While differences in HLOC were evident between nursing and non‐nursing students, no relationship was found between a young woman's HLOC and her lifestyle practices The differences in HLOC showed that nurses were more frequently pure internal whereas most non‐nurses were found to be double externals The pure chance category had the fewest number of respondents The difference in lifestyle practices between these young adult women can be explained in part by curriculum variations, as can the difference in HLOC patterns
Improvement of family carers’ knowledge, skills and attitudes in caring for older people following the implementation of a Family Carers’ Training Program in the community in Indonesia
Authors: Sahar Junaiti , Courtney Mary , Edwards Helen
Published: July 2003

The purpose of this study was to examine family carers’ knowledge, skills and attitudes in caring for older people following the implementation of a Family Carers’ Training Program (FCTP). Family carers (n = 240) from two villages in Indonesia were randomly selected. All participants were surveyed by questionnaires and their care behaviour observed at baseline, three and six months. Findings indicated significant increases in knowledge, skills and attitudes in the intervention group over six months compared to those of the control group. Hence, the FCTP demonstrated a positive effect on family carers’ capabilities and attitudes in caring for older people living in the community in the study setting.
Consumer participation in acute care settings: An Australian experience
Authors: Wellard Sally , Lillibridge Jennifer , Beanland Christine , Lewis Michele
Published: July 2003

Consumer partnerships have been embraced as an important component of building high quality health care services. While nurses have the greatest contact with clients in hospital, little is known of their views about consumer participation or how they facilitate that participation at the bedside. Using focus group interviews and participant observation methods, this project explored nurses’ approaches to working with consumers to support their participation in health care delivery. Findings indicate a sharp contrast between the ideas that nurses expressed and the actions observed in practice. It was clear from the interviews that nurses had adopted the rhetoric surrounding consumer participation, yet observational data revealed nursing practices that excluded active participation by consumers. Factors influencing nurses’ facilitation of consumer participation were identified as the division of nursing labour in the setting, limited communication between nurses and patients and environmental constraints.
Hospital fall risk assessment tools: A critique of the literature
Authors: Myers Helen
Published: July 2003

There are numerous fall risk assessment tools developed for use by nurses in hospitals; however, few of them have established validity and reliability. This article will examine the current state of knowledge in regard to fall risk assessment tools through review and critique of the literature on the topic. Recommendations for future research on fall risk assessment tools will be made and a conceptual framework detailing the relationship between the variables involved in assessing the accuracy of fall risk assessment tools will be presented.
Workplace violence in nursing in Queensland, Australia: A self‐reported study
Authors: Hegney Desley , Plank Ashley , Parker Victoria
Published: July 2003

This paper reports on workplace violence, self‐reported as part of a survey among members of the Queensland Nurses’ Union (QNU) in October 2001. The aim of the overall study was to ascertain how nurses perceived their work and their working conditions and to use the results of the study to inform strategic planning of the QNU. The participants of this study were drawn from a stratified random sample of 2800 QNU members employed in the public, the private acute and the aged care sectors. The total number of completed surveys analysed was 1436: 441 aged care, 497 public and 498 private acute sector surveys. The results suggest that the rate of workplace violence differs significantly across sectors. In the three months immediately prior to the survey, 50% of aged care sector nurses experienced some form of workplace violence compared to 47% of public sector nurses and 29% of acute private sector nurses. The major source of workplace violence was from patients. The second most common source of violence varied. Nurses in the public sector signified visitors and relatives while nurses in the aged care and acute private sectors indicated other nurses. The study found that inexperienced nurses are more likely to report workplace violence than experienced nurses. Additionally, the more experienced the nurse, the less likely they are to perceive workplace policies and procedures for workplace violence as effective. Additional findings include an apparent lack of policies and procedures for workplace violence in rural and remote areas, and an association between the designation of a nurse and the reported level of workplace violence.
A surgeon's look at the treatment of cancer
Authors: Shiu Man‐Hei
Published: July 2003

Radical resection of cancer, such as radical mastectomy and abdominoperineal rectal resection, was developed in the last century. Wide‐field resection and lymph node dissection formed the basic tenets of these operations. Oesophagectomy, hepatectomy, pancreatectomy and other major resections followed. These surgical endeavours led to some spectacular cures, but also frequent postoperative deaths and complications. Advances in surgical technique and medical science have reduced the risk of surgery to an acceptable level. The last two decades have seen patients presenting with earlier and smaller cancers, prompting re‐examination of the basic tenets of oncological resection. Radiotherapy as an adjunct to surgery has reduced the need for wide radical resection of cancer of the breast, rectum and many other sites. Prospective randomized clinical trials have validated the safety of lesser scopes of surgical resection for breast cancer and cutaneous melanoma. The classical radical mastectomy is now seldom carried out. Simple wedge excision (so‐called ‘lumpectomy’) is now the most common operation for breast cancer. Wide radical resection continues to be advocated for cancer of the lung, oesophagus, stomach, and pancreas, but its benefit needs to be confirmed by similar controlled trials. Adjuvant chemotherapy given after resection of breast and colon cancer has proven survival benefit. Chemotherapy can also shrink some bulky, unresectable cancers, making them resectable. Advances in molecular biology have recently allowed the introduction of novel therapeutic agents which can abrogate the growth and progression of some cancers at the molecular level. Technological advances have enabled the development of minimally invasive cancer treatment techniques. Procedures such as radiosurgery, radiofrequency ablation, and video‐assisted endoscopic resections can achieve cancer control with minimized risk and morbidity. The new millennium will see continued evolution in the role of surgery in the treatment of cancer.
Current admission policies of long‐term care facilities in Japan
Authors: Hirakawa Yoshihisa , Masuda Yuichiro , Uemura Kazumasa , Onishi Joji , Hattori Ayako , Kuzuya Masafumi , Iguchi Akihisa
Published: July 2003

Background:  The rapidly aging society in Japan is putting demands on long‐term care facilities for the elderly who require care. In Europe and the USA, there is ongoing reform of elderly care services, but the establishment of system based on social insurance is still being explored in Japan.

Methods:  Two studies were conducted, the first in 2000 and the second in 2001, involving 91 long‐term care facilities located in or around the city of Nagoya. Questionnaires were sent to facility directors, chief administrators or head nurses to inquire about their admission policies for six major patient categories. Two educational lectures on methicillin‐resistant Staphylococcus aureus (MRSA) and urinary incontinence were given between the distribution of the questionnaires.

Results:  For all six categories featured on the questionnaire, the acceptance rate in both studies was the highest in geriatric hospitals, and an improvement in acceptance rates was seen in the second study in all three types of care facilities. When the effect the lectures had on changes in admission policies at these facilities was examined, no correlation was found.

Conclusions:  Lectures should be given to facility management and personnel to raise their awareness of key issues and improve their efficiency.
Plasma homocysteine and cognitive function in elderly patients with diabetes mellitus
Authors: Araki Atsushi , Ito Hideki , Hosoi Takayuki , Orimo Hajime
Published: July 2003

Background:  The purpose of the present paper was to investigate a possible contribution of plasma homocysteine to cognitive impairment. To this end the relationship between plasma homocysteine levels and cognitive performance test results were investigated in elderly patients with diabetes.

Methods:  A total of 144 elderly patients (39 men and 105 women) with diabetes mellitus, who were free of clinical stroke, were studied. Plasma levels of homocysteine, folate, vitamin B12, vitamin B6, and the C677T polymorphism of methylene tetrahydrofolate reductase were determined. Cognitive function was assessed with the Wechsler Adult Intelligence Scale, Revised (digit symbol substitution, backward digit span, similarities, picture arrangement), Stroop test, Benton Visual Retention Test, and Mini‐Mental State Examination (MMSE).

Results:  In elderly women with diabetes, elevated homocysteine levels in the plasma were significantly associated with impairment of cognitive performance assessed with the MMSE, digit symbol substitution test, similarities, Stroop test, and Benton visual retention test, but not the backward digit span test. Multiple logistic regression analyses revealed that the associations between the log‐transformed plasma homocysteine level and low scores of the MMSE and digit symbol substitution test remained significant after adjustment for age, education, hemoglobin (Hb)A1c, systolic blood pressures, insulin treatment, serum levels of folate, vitamin B12, and vitamin B6, and the presence of asymptomatic cerebral infarction on brain magnetic resonance images.

Conclusions:  Elevated plasma homocysteine level was independently associated with cognitive impairment in elderly diabetic women. Because the cause of the association between homocysteine and cognitive impairment remains unclear, future intervention studies are necessary to examine whether reducing plasma homocysteine levels prevents cognitive decline in elderly patients with diabetes mellitus.
Association of tumor necrosis factor receptor 1 gene polymorphism with bone mineral density
Authors: Hoshino Shinjiro , Hosoi Takayuki , Shiraki Masataka , Orimo Hajime , Ouchi Yasuyoshi , Inoue Satoshi
Published: July 2003

Background:  Estrogen deficiency in postmenopausal women causes an increased production of proinflammatory cytokines such as interleukin (IL)‐1, IL‐6, and tumor necrosis factor (TNF)‐α. These cytokines are associated with an increase of bone turnover and an acceleration of bone loss. Tumor necrosis factor‐α is known to promote osteoclastogenesis via TNFR1, one of the tumor necrosis factor receptors (TNFR). Therefore, the purpose of the present report was to investigate the association of TNFR1 gene polymorphism with bone mineral density (BMD) in postmenopausal Japanese women.

Methods:  The question of whether a polymorphism of the TNFR1 gene would correlate with osteoporosis in 320 unrelated healthy postmenopausal women in Japan, was investigated. A single nucleotide polymorphism (SNP) located at Pro12 (CCA to CCG) in exon 1 of TNFR1 was utilized.

Results:  The subjects were categorized into three genotypes: AA, AG, and GG. The frequency of each genotype was 72.2%, 23.8%, and 4.0%, respectively. The association of this polymorphism with BMD of the lumbar spine and total body, and several bone metabolic markers was then examined. Concerning the TNFR1 gene, the AA group had significantly low total body BMD, compared with the AG + GG group (Z score; 0.285 vs 0.568; P = 0.03), although BMD of the lumbar spine was not statistically different.

Conclusion:  These results suggest an association between this SNP of the TNFR1 gene and BMD, and an involvement of TNFR1 in postmenopausal osteoporosis among Japanese.
What determines the life satisfaction of the elderly? Comparative study of residential care home and community in Japan
Authors: Ho Han Kwee , Matsubayashi Kozo , Wada Taizo , Kimura Miyuki , Yano Shoki , Otsuka Kuniaki , Fujisawa Michiko , Kita Toru , Saijoh Kiyofumi
Published: July 2003

Background:  Increasing lifespan has forced elderly persons and researchers alike to look at life and aging in a new way: at adding life to years rather than years to life. With increasing lifestyle choices for the elderly, the present study was undertaken to determine and compare the factors associated with life satisfaction in elderly living in a residential care home and in the community in Japan.

Methods:  This was a cross‐sectional, self‐reported, questionnaire‐based study. Elderly persons from the residential care home in Kyoto City (n = 261, mean age ± SD = 79.6 ± 6.6 years, male : female = 1 : 3.1) and from the town of Urausu, Hokkaido (n = 733, mean age ± SD = 74.8 ± 6.8 years, male : female = 1 : 1.3), participated in the study. This represented 95.3% and 89.5% of all eligible elderly ≥ 65 years in the home and town, respectively. Activities of daily living, higher functions, medical and social history, geriatric depression scale and quality of life were studied. Using multiple logistic regression models, factors associated with high satisfaction of life were identified.

Results:  In community‐dwelling elderly, relationship with friends, as opposed to relationship with family for elderly in residential care home, were factors related to life satisfaction.

Conclusions:  This study demonstrates the relative importance of social factors versus medical and functional factors as determinants of life of elderly. We have also shown how these factors differ for elderly living in different environments. Understanding these different as well as common determinants of life satisfaction from a whole array of diverse ones allows us to make effective strategy to improve the quality of life of elderly living in different conditions.
Four‐year prospective study of the influence of elevated serum lipoprotein (a) concentration on ischemic heart disease and cerebral infarction in elderly patients with type‐2 diabetes
Authors: Suzuki Tatsuya , Oba Kenzo , Igari Yoshimasa , Matsumura Noriaki , Inuzuka Yuki , Kigawa Yoshiaki , Ajiro Yumiko , Okazaki Kyoji , Nakano Hiroshi , Metori Shohei
Published: July 2003

Background:  The purpose of the present paper was to elucidate the influence of an elevated serum lipoprotein (a) (Lp(a)) concentration on the incidence of ischemic heart disease (IHD) and perforating artery occlusion‐type cerebral infarction (CI) in elderly patients with type‐2 diabetes.

Methods:  The serum Lp(a) levels in type‐2 diabetic subjects aged ≥60 years (n = 158; 81 male, 77 female) were measured. At the commencement of the study, subjects were allocated on the basis of past history of CI to a CI– or CI+ group, and on the basis of past history of angina pectoris or myocardial infarction to an IHD– or IHD+ group. They were followed up prospectively for 4 years and the incidences of IHD and CI were monitored. Diagnoses of CI were confirmed by computed tomography (CT), and of myocardial infarction by electrocardiography and blood chemistry. Serum Lp(a) levels of ≥ 20 mg/dL were considered elevated, and < 20 mg/dL as normal. Kaplan–Meier survival analysis (log–rank test) was used to assess the time to event rate stratified by an Lp(a) cut‐off of 20 mg/dL. The predictive value for CI or IHD events was assessed by multiple logistic regression analysis.

Results:  The probability of IHD events was significantly higher in the elevated Lp(a) group than in the normal Lp(a) group without a history of IHD (P < 0.001; log–rank test), but was similar in the two subgroups of subjects with a history of IHD. No significant difference was seen between the elevated Lp(a) and normal Lp(a) groups in the probability of CI events, with or without a history of CI. On multiple logistic regression analysis, Lp(a), hyperlipidemia and a history of IHD were significant predictors of IHD, whereas hypertension, hyperlipidemia and a history of CI were significant predictors of CI.

Conclusion:  These results indicate that an elevated serum Lp(a) concentration is an independent risk factor for IHD, but not for perforating artery occlusion‐type CI, in elderly patients with type‐2 diabetes.
Multidisciplinary team approach for elderly patients
Authors: Tanaka Makoto
Published: July 2003

The multidisciplinary team approach plays an increasingly important role in the management and care of elderly patients, providing support to patients and families and helping them adapt to illness and treatment plans – it offers psychosocial counseling, patient and family education, discharge planning and post hospital care planning. Multidisciplinary team assessment and intervention strategies are also essential in preventing injuries such as falls and delirium as well as in end of life care. Moreover, teaching hospitals are expected to provide team training for medical, nursing and social work students to promote early exposure to interdisciplinary teamwork.
Gene expression in dopamine and GABA systems in an animal model of schizophrenia: effects of antipsychotic drugs
Authors: Lipska Barbara K. , Lerman Daniel N. , Khaing Zin Z. , Weickert Cynthia Shannon , Weinberger Daniel R.
Published: July 2003

We used in situ hybridization histochemistry to assess expression of dopamine receptors (D1R, D2R and D3R), neurotensin, proenkephalin and glutamate decarboxylase‐67 (GAD67) in the prefrontal cortex, striatum, and/or nucleus accumbens in adult rats with neonatal ventral hippocampal (VH) lesions and in control animals after acute and chronic treatment with antipsychotic drugs clozapine and haloperidol. We also acquired these measures in a separate cohort of treatment‐naïve sham and neonatally VH‐lesioned rats used as an animal model of schizophrenia. Our results indicate that the neonatal VH lesion did not alter expression of D1R, D3R, neurotensin or proenkephalin expression in any brain region examined. However, D2R mRNA expression was down‐regulated in the striatum, GAD67 mRNA was down‐regulated in the prefrontal cortex and prodynorphin mRNA was up‐regulated in the striatum of the VH‐lesioned rats as compared with sham controls. Antipsychotic drugs did not alter expression of D1R, D2R or D3R receptor mRNAs but elevated neurotensin and proenkephalin expression in both groups of rats; patterns of changes were dependent on the duration of treatment and brain area examined. GAD67 mRNA was up‐regulated by chronic antispychotics in the nucleus accumbens and the striatum and by chronic haloperidol in the prefrontal cortex in both sham and lesioned rats. These results indicate that the developmental VH lesion changed the striatal expression of D2R and prodynorphin and robustly compromised prefrontal GAD67 expression but did not modify drug‐induced expression of any genes examined in this study.
Endogenous rhythm generation in the pre‐Bötzinger complex and ionic currents: modelling and in vitro studies
Authors: Rybak Ilya A. , Shevtsova Natalia A. , St‐John Walter M. , Paton Julian F. R. , Pierrefiche Olivier
Published: July 2003

The pre‐Bötzinger complex is a small region in the mammalian brainstem involved in generation of the respiratory rhythm. As shown in vitro, this region, under certain conditions, can generate endogenous rhythmic bursting activity. Our investigation focused on the conditions that may induce this bursting behaviour. A computational model of a population of pacemaker neurons in the pre‐Bötzinger complex was developed and analysed. Each neuron was modelled in the Hodgkin–Huxley style and included persistent sodium and delayed‐rectifier potassium currents. We found that the firing behaviour of the model strongly depended on the expression of these currents. Specifically, bursting in the model could be induced by a suppression of delayed‐rectifier potassium current (either directly or via an increase in extracellular potassium concentration, [K+]o) or by an augmentation of persistent sodium current. To test our modelling predictions, we recorded endogenous population activity of the pre‐Bötzinger complex and activity of the hypoglossal (XII) nerve from in vitro transverse brainstem slices (700 µm) of neonatal rats (P0–P4). Rhythmic activity was absent at 3 mm[K+]o but could be triggered by either the elevation of [K+]o to 5–7 mm or application of potassium current blockers (4‐AP, 50–200 µm, or TEA, 2 or 4 mm), or by blocking aerobic metabolism with NaCN (2 mm). This rhythmic activity could be abolished by the persistent sodium current blocker riluzole (25 or 50 µm). These findings are discussed in the context of the role of endogenous bursting activity in the respiratory rhythm generation in vivo vs. in vitro and during normal breathing in vivo vs. gasping.
Connexin43 is not expressed in principal cells of mouse cortex and hippocampus
Authors: Theis Martin , Söhl Goran , Speidel Dina , Kühn Ralf , Willecke Klaus
Published: July 2003

Previous immunofluorescence analyses in mice and rats showed a mainly astrocytic expression of the gap junction protein connexin43 (Cx43) in brain. However, in situ hybridization of murine brain sections suggested strong expression of Cx43 mRNA in hippocampal and cortical pyramidal neurons and Purkinje cells. These findings contrast with recent immunoelectron microscopic studies that excluded prominent Cx43 protein expression in neurons. Both contrasting results could be explained by post‐transcriptional control mechanisms. Here we demonstrate by conditional replacement of the Cx43 coding region by a lacZ reporter gene, mimicking transcriptional activity of the Cx43 gene, that Cx43 is not expressed in principal cells of murine brain. This histochemical approach used is not prone to cross‐reactivity of mRNA probes or antibodies. Furthermore, we show that in situ hybridization signals, suggested to be specific for Cx43 in mouse neurons, are retained even when the Cx43 coding DNA in neurons is removed by cre‐mediated deletion. Our results confirm the previous findings of a mainly astrocytic expression of Cx43 in adult mouse brain and underscore the importance of connexin‐deficient mice as controls for in situ hybridization studies. We found no evidence for post‐transcriptional control of the Cx43 gene in principal neurons. Thus, the synchronized activity of neuronal networks cannot depend on Cx43 containing gap junctions in these cells.
Binding characteristics of [3H]14‐methoxymetopon, a high affinity µ‐opioid receptor agonist
Authors: Spetea Mariana , Tóth Fanni , Schütz Johannes , Ötvös Ferenc , Tóth Géza , Benyhe Sandor , Borsodi Anna , Schmidhammer Helmut
Published: July 2003

The highly potent µ‐opioid receptor agonist 14‐methoxymetopon (4,5α‐epoxy‐3‐hydroxy‐14β‐methoxy‐5β,17‐dimethylmorphinan‐6‐one) was prepared in tritium labelled form by a catalytic dehalogenation method resulting in a specific radioactivity of 15.9 Ci/mmol. Opioid binding characteristics of [3H]14‐methoxymetopon were determined using radioligand binding assay in rat brain membranes. [3H]14‐Methoxymetopon specifically labelled a single class of opioid sites with affinity in low subnanomolar range (Ki = 0.43 nm) and maximal number of binding sites of 314 fmol/mg protein. Binding of [3H]14‐methoxymetopon was inhibited by ligands selective for the µ‐opioid receptor with high potency, while selective κ‐opioids and δ‐opioids were weaker inhibitors. 14‐Methoxymetopon increased guanosine‐5′‐O‐(3‐[35S]thio)‐triphosphate ([35S]GTPγS) binding with an EC50 of 70.9 nm, thus, providing evidence for the agonist character of this ligand. The increase of [35S]GTPγS binding was inhibited by naloxone and selective µ‐opioid antagonists, indicating a µ‐opioid receptor‐mediated action. [3H]14‐Methoxymetopon is one of the few nonpeptide µ‐opioid receptor agonists available in radiolabelled form up to now. Due to its high affinity and selectivity, high stability and extremely low nonspecific binding (<10%), this radioligand would be an important and useful tool in probing µ‐opioid receptor mechanisms, as well as to promote a further understanding of the opioid system at the cellular and molecular level.
Distribution of central sensory axons in transgenic mice overexpressing nerve growth factor and lacking functional p75 neurotrophin receptor expression
Authors: Hannila Sari S. , Kawaja Michael D.
Published: July 2003

This study examined the roles of nerve growth factor (NGF) and the p75 neurotrophin receptor (p75NTR) in the growth of dorsal root ganglion (DRG) central processes in the dorsal horn. Two genetically modified mouse strains were used: transgenic mice that overexpress NGF in the CNS under the control of the glial fibrillary acidic protein promoter, and p75NTR exon III null mutant mice that express a hypomorphic form of this receptor. In both NGF transgenic and nontransgenic mice with hypomorphic expression of p75NTR, there is a significant loss of DRG neurons compared to mice with normal p75NTR expression. This reduction in neuron number has been shown to underlie a corresponding decrease in peripheral nociceptive sensory innervation. Within the CNS, however, nociceptive innervation of the dorsal horn appears to be unaffected by hypomorphic expression of p75NTR. Comparisons of calcitonin gene‐related peptide immunoreactivity in the dorsal horn revealed that the area occupied by DRG central processes was not significantly different between p75NTR hypomorphic mice and wild‐type siblings, or between NGF transgenic mice with either hypomorphic or normal expression of p75NTR. We propose that DRG central processes arborize extensively in both NGF‐transgenic and nontransgenic p75NTR hypomorphic mice in order to compensate for the loss of DRG neurons and restore dorsal horn innervation to normal levels. We also present evidence suggesting that NGF plays only a minor role in the growth of DRG central processes.
Dopamine and adenosine mediate substance P‐induced depression of evoked IPSCs in the rat nucleus accumbens in vitro
Authors: Kombian Samuel B. , Ananthalakshmi Kethireddy V. V. , Parvathy Subramanian S. , Matowe Wandikayi C.
Published: July 2003

The major projection cells of the nucleus accumbens (NAc) are under a strong inhibitory influence from GABAergic afferents and depend on afferent excitation to produce their output. We have earlier reported that substance P (SP), a peptide which is colocalized with GABA in these neurons, depresses excitatory synaptic transmission in this nucleus (Kombian, S.B., Ananthalakshmi, K.V.V., Parvathy, S.S. & Matowe, W.C. (2003) J. Neurophysiol., 89, 728–738). In order to better understand the role of this peptide in the synaptic physiology of the NAc, it is important to determine its effects on inhibitory synaptic responses. Using whole‐cell recording in rat forebrain slices, we show here that SP also depresses evoked inhibitory postsynaptic currents (IPSCs) in the NAc via intermediate neuromodulators. SP caused a partially reversible, dose‐dependent decrease in evoked IPSC amplitude. This effect was present without measurable changes in the holding current, input resistance of recorded cells or decay rate (τ) of IPSCs. It was mimicked by a neurokinin‐1 (NK1) receptor‐selective agonist, [Sar9, Met (O2)11]‐SP, and blocked by an NK1 receptor‐selective antagonist, L 732 138. The SP‐induced IPSC depression was prevented by SCH23390, a dopamine D1‐like receptor antagonist and by 8‐cyclopentyltheophylline, an adenosine A1 receptor blocker. Furthermore, the SP effect was also markedly attenuated by exogenous adenosine, dipyridamole, rolipram and barium. These data show that SP, acting on NK1 receptors, depresses inhibitory synaptic transmission indirectly by enhancing extracellular dopamine and adenosine levels. SP therefore acts in the NAc to modulate both excitatory and inhibitory afferent inputs using the same mechanism(s).
Dissociation between top‐down attentional control and the time course of visual attention as measured by attentional dwell time in patients with mild cognitive impairment
Authors: Perry Richard J. , Hodges John R.
Published: July 2003

Studies of the time course of visual attention have identified a temporary functional blindness to the second of sequentially presented stimuli in that the attentional cost of attending to one visual stimulus may lead to impairments in identifying a second stimulus presented within 500 ms of the first. This phenomenon is known as the attentional blink or attentional dwell time. The neural correlates of the attentional blink and its relationship to mechanisms that control attention are unknown. To examine this relationship we tested healthy controls and subjects in the preclinical stage of Alzheimer's disease, known as mild cognitive impairment (MCI), on a paradigm which affords quantification of both the attentional blink and the top‐down control of attention. When subjects were asked to identify both a number and a letter that were rapidly and sequentially presented on a visual display, the detrimental effect that identifying the first stimulus had on the ability to identify the second served as a measure of the attentional blink. When asked to identify only one of the two stimuli, the ability to ignore the first stimulus was a function of their top‐down attentional control. The MCI subjects demonstrated a normal attentional dwell time but in contrast they showed impaired top‐down attentional control within the same paradigm. This dissociation suggests that these two aspects of visual attention are subserved by different neural systems. The possible neural correlates of these two attentional functions are discussed.
The effect of urocortin on ingestive behaviours and brain Fos immunoreactivity in mice
Authors: Sinnayah P. , Blair‐West J. R. , McBurnie M. I. , McKinley M. J. , Oldfield B. J. , Rivier J. , Vale W. W. , Walker L. L. , Weisinger R. S. , Denton D. A.
Published: July 2003

The influence of urocortin (UCN) on ingestive behaviours and brain neural activity, as measured immunohistochemically by the presence of Fos protein, was determined in mice. Rat UCN was administered by continuous intracerebroventricular (ICV) or subcutaneous (SC) infusion. ICV infusion of UCN (100 ng/h, 14 days) transiently reduced daily food and water intakes (days 1–4) but body weight was reduced from day 2 into the post‐infusion period. Sodium intake was reduced from day 3 to the end of infusion. SC infusion of UCN caused similar but smaller reductions in food and water intakes and body weight, without change in sodium intake. In separate experiments, Fos immunoreactivity was increased in several brain nuclei known to be involved in the control of body fluid and energy homeostasis, e.g. central nucleus of the amygdala, median preoptic nucleus, bed nucleus of the stria terminalis and arcuate nucleus. Increased Fos expression was similar for ICV and SC infusions when measured on days 2–3 or 6–7 of infusion. In conclusion, increases of brain activity by UCN may be associated with stimulation of adrenocorticotrophic hormone release and sympathetic nervous activity, but increases may also indicate suppression of ingestive behaviours by stimulating central inhibitory mechanisms located in areas known to control body fluid and energy homeostasis.
Insulin‐like growth factor II mRNA is expressed in neurones of the brain of the bony fish Oreochromis mossambicus, the tilapia
Authors: Caelers Antje , Schmid Annette C. , Hrusovsky Andrea , Reinecke Manfred
Published: July 2003

The physiological meaning of insulin‐like growth factor II (IGF‐II) is still enigmatic. IGF‐II occurs in the adult mammalian brain where it is expressed in the mesodermal portion of the choroid plexus and the meninges, but results on its presence in cells of neuroepithelial origin are controversial. However, IGF‐II mRNA is transiently expressed in neurones during mammalian early development. In bony fish, IGF‐II mRNA is also present in the adult brain but nothing is known about its synthesis sites. Thus, the present study using in situ hybridization with digoxigenin‐labelled RNA species‐specific probes investigates the cellular distribution of IGF‐II mRNA in the adult brain of a bony fish, the tilapia (Oreochromis mossambicus). As in mammals, IGF‐II mRNA was strongly expressed in the choroid plexus and meninges. Thus, IGF‐II synthesis by choroid plexus and meninges seems to have a long evolutionary history and may be common to all vertebrates. However, as shown by the detailed investigation of landmark nuclei and regions, IGF‐II mRNA occurred also in numerous neurones at all levels of the tilapia brain. The distinct localization of IGF‐II mRNA in neurones might indicate that neuronal IGF‐II acts as transmitter or modulator. However, the widespread occurrence of the IGF‐II‐producing neurones argues against this assumption and most probably suggests that IGF‐II plays a role in the differentiation, maintenance and regeneration of neurones. It is further assumed that the sustained neuronal IGF‐II expression in the brain of the adult tilapia correlates with continued post‐embryonic up to life‐long brain growth as has been shown in many teleost fishes.
Enkephalin contributes to the locomotor stimulating effects of 3,4‐methylenedioxy‐N‐methylamphetamine
Authors: Compan V. , Scearce‐Levie K. , Crosson C. , Daszuta A. , Hen R.
Published: July 2003

3,4‐Methylenedioxy‐N‐methylamphetamine (MDMA, ‘Ecstasy’) is a potent inhibitor of serotonin uptake, which induces both an increase in locomotion and a decrease in exploratory activity in rodents. Serotonin 5‐HT1B receptors, located on the terminals of striatal efferent neurons, have been suggested to mediate these motor effects of MDMA. Striatal neurons projecting to the globus pallidus contain met‐enkephalin, whilst those projecting to the substantia nigra contain substance P. We therefore analysed the levels of both peptides using radioimmunocytochemistry after MDMA administration (10 mg/kg, 3 h) in wild‐type and 5‐HT1B receptor knockout mice. Our results demonstrate that MDMA induces a decrease in pallidal met‐enkephalin immunolabelling in wild‐type, but not in 5‐HT1B receptor knockout mice. Similar results were obtained following treatment with the 5‐HT1A/1B agonist RU24969 (5 mg/kg, 3 h), suggesting that activation of 5‐HT1B receptors leads to a reduction in met‐enkephalin levels in the globus pallidus. In contrast, MDMA had no effect on the nigral substance P levels. We have previously shown that both MDMA and RU24969 fail to stimulate locomotor activity in 5‐HT1B receptor knockout mice. Our present data indicate that the opioid antagonist naloxone suppressed the locomotor effects of MDMA. This study is the first to demonstrate that Enk contributes to MDMA‐induced increases in locomotor activity. Such an effect may be related to the 5‐HT control of pallidal met‐enkephalin levels via the 5‐HT1B receptors.
Tonotopic representation of missing fundamental complex sounds in the human auditory cortex
Authors: Fujioka Takako , Ross Bernhard , Okamoto Hidehiko , Takeshima Yasuyuki , Kakigi Ryusuke , Pantev Christo
Published: July 2003

The N1m component of the auditory evoked magnetic field in response to tones and complex sounds was examined in order to clarify whether the tonotopic representation in the human secondary auditory cortex is based on perceived pitch or the physical frequency spectrum of the sound. The investigated stimulus parameters were the fundamental frequencies (F0 = 250, 500 and 1000 Hz), the spectral composition of the higher harmonics of the missing fundamental sounds (2nd to 5th, 6th to 9th and 10th to 13th harmonic) and the frequencies of pure tones corresponding to F0 and to the lowest component of each complex sound. Tonotopic gradients showed that high frequencies were more medially located than low frequencies for the pure tones and for the centre frequency of the complex tones. Furthermore, in the superior–inferior direction, the tonotopic gradients were different between pure tones and complex sounds. The results were interpreted as reflecting different processing in the auditory cortex for pure tones and complex sounds. This hypothesis was supported by the result of evoked responses to complex sounds having longer latencies. A more pronounced tonotopic representation in the right hemisphere gave evidence for right hemispheric dominance in spectral processing.
Effects of a Thin‐Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation
Authors: SCHUCHERT ANDREAS , MEINERTZ THOMAS
Published: July 2003

SCHUCHERT, A., et al.: Effects of a Thin‐Sized Lead Body of a Transvenous Single Coil Defibrillation Lead on ICD Implantation. In the interest of patients receiving implantable cardioverter defibrillators (ICDs), the clinical benefits of newer and thinner transvenous defibrillation leads have to be determined. The aims of this study were to evaluate the ICD procedure duration and the frequency of lead dislocation at the 3‐month follow‐up of a new defibrillation lead with a thin‐sized lead body and its conventionalsized predecessor. The thin‐sized single coil defibrillation lead (Kainox RV, Biotronik; lead body 6.7 Fr) was implanted in 61 patients and the conventional‐sized defibrillation lead (SPS, Biotronik; lead body 7.8 Fr) in 60 patients. Both leads were connected to a left‐sided, prepectorally implanted Phylax ICD (Biotronik) with active housing. The lead implantation time and total procedure duration were determined. Lead implantation time was defined as the time from lead insertion to the end of the pacing measurements. The total procedure duration spanned skin incision to closure. The incidence of lead repositioning during the lead implantation time and during ventricular fibrillation conversion testing was also assessed. The frequency of lead dislocations was recorded at the 3‐month follow‐up. Mean lead implantation time and total procedure duration of the thin‐sized lead (23 ± 22 minutes 76 ± 37 minutes) were not statistically different from the time needed for the conventional‐sized lead (22 ± 20 minutes 81 ± 34 minutes). The number of lead repositionings during the lead implantation time was similar (thin‐sized lead: 1.4 ± 2.4; conventional‐sized lead: 1.1 ± 1.9). An additional lead repositioning was not necessary during ventricular fibrillation conversion testing in 93.4% of the patients with thin‐sized and in 94.4% with conventional‐sized leads (not significant). At the 3‐month follow‐up, there were four (6.6%) lead dislocations in the thin‐sized and four (6.7%) in the conventional‐sized lead group. In conclusion, the downsized lead body of the new defibrillation lead influenced neither ICD procedure duration nor the incidence of lead dislocation during follow‐up.
Clinical Evaluation of a Pacemaker Algorithm That Adjusts the Pacing Rate During Sleep Using Activity Variance
Authors: DURU FIRAT , BLOCH KONRAD E. , WEILENMANN DANIEL , CANDINAS RETO
Published: July 2003

DURU, F., et al.: Clinical Evaluation of a Pacemaker Algorithm That Adjusts the Pacing Rate During Sleep Using Activity Variance. Even though rate responsive pacemakers are able to regulate pacing rates based on sensor activity, they are set with a minimum rate that is not adjusted to provide rate decreases during sleep. The aim of this study was to evaluate the performance of the “Sleep Rate” feature, as compared to patient diaries and a validated method that identifies sleep from wrist actigraphy. In 19 patients (15 men; age 69 ± 8 years) with Pacesetter Trilogy DR+ pacemakers, the base rate and the sleep rate were set to 80 and 50 ppm, respectively. When the patients returned 2 days later, data recorded by the pacemaker and wrist actigraph were analyzed to find the agreement in corresponding sleep/wake periods. In 17 (89%) patients, the pacemaker went into the sleep mode. The total sleep time derived from actigraphy significantly exceeded the time during which the pacemaker was in sleep mode (1156.8 ± 83.4 vs 307.3 ± 77.2 minutes). Frequent reversions out of the sleep mode limited the total sleep time derived from the pacemaker. Cumulative analysis of the pacemaker data showed that the maximum time in the sleep mode was 78 minutes, and exceeded 1 hour in six instances, 30 minutes in 32 instances, and 15 minutes in 83 instances. Epoch by epoch comparisons revealed a good agreement (93.6 ± 1.8%) during wakefulness between the corresponding actigraph and pacemaker epochs. However, only 24.6 ± 3.7% of the corresponding epochs during sleep were identical, and the overall agreement was 54.4 ± 3.7%. Except for one patient who reported palpitations, patients did not suffer from a pacemaker rate change. The Sleep Rate feature provides rate reduction during sleep, while assuring rapid frequency response during physical activity. However, the current algorithm does not allow long periods of slow pacing rate during continuous sleep, possibly due to its conservative design and the presence of movement arousals, which has to be improved in future generation algorithms.
Electromagnetic Interference of an Implantable Loop Recorder by Commonly Encountered Electronic Devices
Authors: DE COCK CAREL C. , SPRUIJT HUGO J. , VAN CAMPEN LINDA M.C. , PLU ANDRIES W. , VISSER CEES A.
Published: July 2003

De COCK, C.C., et al.: Electromagnetic Interference of an Implantable Loop Recorder by Commonly Encountered Electronic Devices. Electromagnetic interference of pacemaker systems has been well established and can lead to an inappropriate function of these devices. Recently, an implantable loop recorder (ILR) (REVEAL, Medtronic Inc.) has been introduced to evaluate the possible arrhythmic etiology of patients with recurrent syncope. We evaluated the interference of this device in two patients with implantable ILR and in three nonimplanted ILRs with four electromagnetic sources: cellular phones (GSMs), electronic article surveillance systems (EASs), metal detector gates (MDGs), and magnetic resonance imaging (MRI). The GSM did not affect appropriate function of the ILR whereas radiofrequency (RF) EAS could interfere with normal function in implanted and nonimplanted systems. The MDG had no influence on ILR function. The magnetic field induced by the MRI resulted in an irreversible error in one nonimplanted ILR. Therefore, although interference between electromagnetic sources and ILRs appears to be rare in our study, physicians should be aware of possible malfunctioning of these devices.