bluuebunny/crossref_metadata_2025 huggingface dataset:
Heart Rate, Arterial Stiffness, and Wave Reflections in Paced Patients
Authors: Albaladejo Pierre , Copie Xavier , Boutouyrie Pierre , Laloux Brigitte , Déclère André Descorps , Smulyan Harry , Bénétos Athanase
Published: September 2007

Elevated heart rate (HR) and pulse pressure (PP) have a cumulative effect on cardiovascular risk, with the exception of HR ≥100 bpm. How an increase in HR may influence the PP level has never been investigated. In 11 patients with pacemaker monitoring, aortic (pulse-wave analysis) and digital (photoplethysmographic device) blood pressure were measured at 3 different levels of HR, together with determinations of carotid dimensions (echo tracking technique), wave reflections (pulse-wave analysis), and aortic pulse-wave velocity. Increased HR is associated with the following: (1) a significant increase of digital systolic, diastolic, and mean blood pressure; (2) a significant reduction of digital and carotid PP, with a more pronounced reduction of the carotid than of the digital PP, resulting in a significant PP amplification; and (3) a reduction in the time required for the backward pressure wave to return toward the heart, without any change of arterial stiffness. Increased HR significantly enhances PP amplification, leading to an increase of peripheral blood pressure without comparable change in central blood pressure. These results are important to consider for a better understanding of cardiovascular risk and the mechanism of white-coat hypertension.
Enalapril Attenuates Oxidative Stress in Diabetic Rats
Authors: de Cavanagh Elena M.V. , Inserra Felipe , Toblli Jorge , Stella Inés , Fraga César G. , Ferder León
Published: September 2007

Oxidative stress is involved in both the pathogenesis and complications of diabetes. ACE inhibitors can slow the progression of cardiac and renal impairments related to diabetes. The effect of enalapril treatment on oxidative stress and tissue injury was studied in hearts, kidneys, and livers from streptozotocin-induced diabetic rats. Twenty-four rats were divided into the following groups: streptozotocin (65 mg/kg, single intraperitoneal dose), streptozotocin+enalapril (20 mg enalapril/L drinking water), and control (intraperitoneal saline). Seven months after streptozotocin injection, organs were studied by light microscopy and collagen III immunolabeling. Tissue lesions and collagen labeling were graded by a semiquantitative score (0 to 4). Total glutathione content, glutathione redox status (reduced/oxidized glutathione), antioxidant enzyme activities, protein-associated sulfhydryls, thiobarbituric acid–reactive substances, and fluorescent chromolipids were determined in tissue homogenates. Glycemia was higher in both the streptozotocin and streptozotocin+enalapril groups relative to the control group. In the streptozotocin group, creatinine clearance and body weight were lower, and systolic blood pressure and urinary albumin excretion were higher than in the streptozotocin+enalapril and control groups. Heart, kidney, and liver lesion/labeling scores were significantly higher in the streptozotocin group compared with the streptozotocin+enalapril and control groups. Kidney and liver total glutathione was lower in the streptozotocin group relative to the control group (
P
<0.05). Enalapril treatment significantly attenuated the reduction of total glutathione. In the heart, kidney, and liver, both glutathione and proteins were relatively more oxidized in the streptozotocin group relative to the control group (
P
<0.05). Protein and glutathione oxidation were attenuated in the streptozotocin+enalapril group in the 3 tissues studied (
P
<0.05). Enalapril treatment attenuated the oxidation of lipids in the heart and kidney (
P
<0.05). Tissue fibrosis scores were inversely correlated with (1) both total glutathione and reduced/oxidized glutathione in heart, kidney, and liver and (2) glutathione reductase activity in the kidney. These results suggest that in streptozotocin-induced diabetic rats, the protective action of enalapril might be mediated, at least in part, by its effect on tissue oxidant/antioxidant status.
Central Human Cocaine- and Amphetamine-Regulated Transcript Peptide 55–102 Increases Arterial Pressure in Conscious Rabbits
Authors: Matsumura Kiyoshi , Tsuchihashi Takuya , Abe Isao
Published: September 2007

We determined cardiovascular and neurohormonal responses to intracerebroventricular administration of human cocaine- and amphetamine-regulated transcript (CART) peptide 55–102 in conscious rabbits. Intracerebroventricular injection of CART 55–102 elicited dose-related increases in mean arterial pressure and renal sympathetic nerve activity. Peak values of mean arterial pressure and renal sympathetic nerve activity induced by intracerebroventricular injection of 1 nmol of CART 55–102 (+5.0±2.6 mm Hg and +72.5±20.8%) were obtained 40 and 60 minutes after injection, respectively. Plasma epinephrine and glucose concentrations significantly increased 30 and 60 minutes after intracerebroventricular injection of CART 55–102 (control versus 60 minutes for epinephrine, 77.0±62.4 versus 1067.5±329.3 pg/mL,
P
<0.01; for glucose, 6.25±0.33 versus 11.57±0.93 mmol/L,
P
<0.01). Plasma norepinephrine concentrations also significantly increased at 30 minutes. Plasma insulin, vasopressin, and cortisol concentrations increased at 60 minutes but did not attain significant values. However, pretreatment with intravenous injection of pentolinium (5 mg/kg), a ganglion-blocking agent, eliminated these cardiovascular and neurohormonal responses. In contrast, intravenous injection of the same dosage of CART 55–102 (1 nmol) as that used in the intracerebroventricular experiment failed to cause any cardiovascular and renal sympathetic nerve responses. These results suggest that intracerebroventricular human CART 55–102 acts in the central nervous system and activates sympathoadrenal outflow, which results in increases in arterial pressure and plasma glucose levels in conscious rabbits.
Low-Dose Estrogen Supplementation Improves Vascular Function in Hypogonadal Men
Authors: Komesaroff Paul A. , Fullerton Meryl , Esler Murray D. , Dart Anthony , Jennings Garry , Sudhir Krishnankutty
Published: September 2007

It is widely accepted that in women, estrogens provide protection against the development of cardiovascular disease. However, the cardiovascular role of estrogens in men remains uncertain, despite preliminary evidence that endogenous estrogens produced by aromatization of androgenic precursors are of physiological importance. Hypogonadal men have very low levels of circulating estrogen. We studied the responsiveness of forearm resistance arteries to vasoconstrictor and vasodilator agents in 12 men (mean±SEM age, 68.7±2.6 years) rendered hypogonadal as a result of treatment for prostatic cancer, before and after 8 weeks of estrogen supplementation (estradiol valerate 1 mg daily; n=7) or placebo (n=5). Forearm blood flow was measured by venous occlusion plethysmography, and vasoactive agents were infused through a brachial artery cannula in doses that did not affect blood pressure or heart rate. Estrogen supplementation was well tolerated, with no adverse effects. After estrogen treatment, mean estradiol levels increased from <30 to 308±65 pmol/L, and both systolic and diastolic blood pressures were reduced. HDL cholesterol levels increased significantly, and vasoconstrictor responses to the NO synthase inhibitor

N
G

-monomethyl-

l

-arginine (1, 2, 4 μmol/min) were enhanced. Vasoconstrictor responses to angiotensin II (8, 16, 32 ng/min) were markedly attenuated by estrogen treatment, as were vasoconstrictor responses to norepinephrine (25, 50, 100 ng/min). Estrogen did not alter the vasodilator responses to acetylcholine (9.25, 18.5, 37 μg/min) or to the endothelium-independent agent sodium nitroprusside (1.6 μg/min). Responses to all vasoactive agents were unchanged after administration of placebo. We conclude that low-dose estrogen supplementation in hypogonadal men is well tolerated, lowers blood pressure, and may affect vascular reactivity in a manner that is potentially beneficial, through several mechanisms, including enhancement of basal NO release and attenuation of vasoconstrictor responses to angiotensin II and norepinephrine. These findings suggest the need to consider a possible clinical role for estrogenic compounds in cardiovascular risk reduction in some groups of men.
Possible Involvement of Rho-Kinase in the Pathogenesis of Hypertension in Humans
Authors: Masumoto Akihiro , Hirooka Yoshitaka , Shimokawa Hiroaki , Hironaga Kiyoshi , Setoguchi Soko , Takeshita Akira
Published: September 2007

Rho-kinase plays an important role in modulating Ca
2+
sensitivity of vascular smooth muscle and has been suggested to be involved in the increased systemic vascular resistance in hypertensive animals. However, it remains to be examined whether this is also the case in patients with essential hypertension. Recently, it has been shown that fasudil is a specific Rho-kinase inhibitor. The aim of this study was to examine whether Rho-kinase is involved in the pathogenesis of hypertension in humans by using this Rho-kinase inhibitor. Studies were performed in hypertensive patients (HT group, n=14) and age-matched normotensive subjects (NT group, n=12). Forearm blood flow was measured by a strain-gauge plethysmograph during intra-arterial infusion of graded doses of fasudil (3.2, 6.4, 12.8, and 25.6 μg/min) or sodium nitroprusside (0.4, 0.8, 1.6, and 3.2 μg/min). Resting forearm vascular resistance was significantly higher in the HT group than in the NT group (22±4 versus 17±5 U, respectively; P<0.05). The extent of the increase in forearm blood flow evoked by fasudil was significantly greater in the HT group than in the NT group (12.3±1.4 versus 6.0±0.6 mL · min
−1
· 100 mL
−1
, respectively;
P
<0.01). The percent decrease in forearm vascular resistance was significantly greater in the HT group than in the NT group (63.6±4.7% versus 29.6±3.9%, respectively;
P
<0.01). By contrast, forearm vasodilator response evoked by sodium nitroprusside was comparable between the 2 groups. These results provide the first evidence that Rho-kinase may be involved in the pathogenesis of the increased peripheral vascular resistance in hypertension in humans.
Cardiomyocyte Apoptotic Cell Death in Arterial Hypertension
Authors: Fortuño Maria Antonia , Ravassa Susana , Fortuño Ana , Zalba Guillermo , Díez Javier
Published: September 2007

Hypertensive heart disease is a progressive condition in which the compensatory left ventricular hypertrophy that maintains cardiac output leads to myocardial remodeling, characterized by fibrosis, insufficient vascularization, and alterations in cardiomyocytes, including contractile disturbances, changes in gene expression, and decrease in the number of cells. Structural abnormalities in the myocardial wall accelerate the development of diastolic and systolic dysfunction, resulting in heart failure. Many observations point to the apoptotic cell death of cardiomyocytes as a relevant factor in the transition from compensatory hypertrophy to pump failure in experimental and human hypertension. Potential inducers of cardiomyocyte apoptosis in overloaded hearts include extrinsic factors, such as mechanical forces, neurohormonal activation, oxidative stress, hypoxia, and cytokines. Some lines of evidence indicate that angiotensin II and the overstretching of cardiomyocytes are originally involved in the triggering of apoptosis in hypertension, whereas other factors are being investigated. Furthermore, intracellular changes, such as downregulation of survival proteins or activation of death proteins, seem to play an important role. The assumption that the apoptosis of cardiomyocytes worsens hypertensive heart disease prognosis brings forth new approaches to avoid or slow the transition to pump failure. In this respect, experimental data indicate that currently used antihypertensive drugs interfere with cardiomyocyte apoptosis. Moreover, the knowledge of intracellular apoptotic processes in cardiomyocytes provides novel therapeutic strategies to be added to the multimodal approach in the prevention of heart failure.
A Computerized Algorithm for Etiologic Classification of Ischemic Stroke
Authors: Ay Hakan , Benner Thomas , Murat Arsava E. , Furie Karen L. , Singhal Aneesh B. , Jensen Matt B. , Ayata Cenk , Towfighi Amytis , Smith Eric E. , Chong Ji Y. , Koroshetz Walter J. , Sorensen A. Gregory
Published: September 2007

Background and Purpose—

The SSS-TOAST is an evidence-based classification algorithm for acute ischemic stroke designed to determine the most likely etiology in the presence of multiple competing mechanisms. In this article, we present an automated version of the SSS-TOAST, the Causative Classification System (CCS), to facilitate its utility in multicenter settings.

Methods—

The CCS is a web-based system that consists of questionnaire-style classification scheme for ischemic stroke (http://ccs.martinos.org). Data entry is provided via checkboxes indicating results of clinical and diagnostic evaluations. The automated algorithm reports the stroke subtype and a description of the classification rationale. We evaluated the reliability of the system via assessment of 50 consecutive patients with ischemic stroke by 5 neurologists from 4 academic stroke centers.

Results—

The kappa value for inter-examiner agreement was 0.86 (95% CI, 0.81 to 0.91) for the 5-item CCS (large artery atherosclerosis, cardio-aortic embolism, small artery occlusion, other causes, and undetermined causes), 0.85 (95% CI, 0.80 to 0.89) with the undetermined group broken into cryptogenic embolism, other cryptogenic, incomplete evaluation, and unclassified groups (8-item CCS), and 0.80 (95% CI, 0.76 to 0.83) for a 16-item breakdown in which diagnoses were stratified by the level of confidence. The intra-examiner reliability was 0.90 (0.75–1.00) for 5-item, 0.87 (0.73–1.00) for 8-item, and 0.86 (0.75–0.97) for 16-item CCS subtypes.

Conclusions—

The web-based CCS allows rapid analysis of patient data with excellent intra- and inter-examiner reliability, suggesting a potential utility in improving the fidelity of stroke classification in multicenter trials or research databases in which accurate subtyping is critical.
Ukraine Imports Democracy: External Influences on the Orange Revolution
Authors: McFaul Michael
Published: September 2007

Can the West promote democracy? An examination of one critical case, the 2004 Orange Revolution in Ukraine, offers a unique method for generating answers to this important theoretical and policy question. Tracing the causal impact of external influences first requires a theory of democratization composed exclusively of domestic factors, specifically the changing distribution of power between the autocratic regime and democratic challengers. Once these internal factors have been identified, the extent to which external factors influenced either the strength of the autocratic regime or the democratic challengers can be measured. Domestic factors accounted for most of the drama of the Orange Revolution, but external factors did play a direct, causal role in constraining some dimensions of autocratic power and enhancing some dimensions of the opposition's power. International assistance in the form of ideas and financial resources was crucial to only one dimension of the Orange Revolution: exposing fraud. Yet significant international inputs also can be identified regarding the preservation of semi-autocracy, the nurturing of an effective political opposition, the development of independent media, and the capacity to mobilize protesters after the falsified presidential vote.
On the Design and Performance of an Adaptive, Global Strategy for Detecting and Mitigating Distributed DoS Attacks in GRID and Collaborative Workflow Environments
Authors: Znati Taieb , Amadei James , Pazehoski Daniel R. , Sweeny Scott
Published: September 2007

While intrusion detection systems have seen a great deal of commercialization in recent years, these products are not geared towards environments, which require support for high-performance applications and open access policy for collaboration. A second limitation of existing intrusion detection systems is their lack of flexibility to deal with the ever-evolving characteristics of the attacks, in terms of diversity and intensity. Moreover, applications in high-performance collaborative environments are very diverse, with possible extreme performance requirements. Consequently, effective strategies to detect attacks in these environments strongly depend on how closely the underlying intrusion detection mechanisms reflect the “specifics” of the application. The focus of this paper is on secure GRID and workflow environments. The purpose is to investigate a distributed defense method that can secure collaborative GRID and workflow environments and neutralize attacks before they reach their potential target en mass. To this end, the paper proposes a progressive, globally deployable sentinel scheme for data sampling, packet inspection, and DoS attack detection and recovery. A simulation framework is developed to study the performance of the proposed scheme. The results show a significant improvement in how the network deals with DoS attacks to secure GRID and workflow environments, in comparison to local DoS detection and prevention schemes.
Simulation Perspectives on Link Buffer Sizing
Authors: Gorinsky Sergey , Kantawala Anshul , Turner Jonathan
Published: September 2007

The problem of determining the optimal buffer size for an Internet link has recently attracted the strong revived attention of networking scientists. While consonant in dissenting from the conventional wisdom to set the buffer size to the product of the link bitrate and round-trip propagation delay of served connections, the new studies often propose alternative guidelines that starkly contradict each other. In this paper, we review the problem of link buffer sizing from two simulation perspectives. First, we use the packet-level simulator ns-2, which is currently the predominant tool for evaluation of network designs, to explore the contradictions between the buffer sizing guidelines. We attribute the contradictions to differences in assumptions and goals of the earlier studies and present our own argument for using small constant buffer sizes. Second, we reflect on the suitability of ns-2 itself for studying the problem of link buffer sizing. We the identify ns-2 deficiencies that undermine the trustworthiness of results provided by this prevailing simulation tool. We also suggest directions and discuss challenges for designing a simulation methodology capable of providing undisputed answers on link buffer sizing.
Performance Evaluation of CAC Schemes for Multi-service Traffic Environment in 3G Networks
Authors: Ahmad Waqas , Awan Irfan
Published: September 2007

The ever-growing mobile market and the number of services offered by the network providers, which are increasing with every passing day, has reinforced the need for optimized CAC schemes. The introduction of Code Division Multiple Access (CDMA) has resulted in extensive reuse of frequency and therefore the birth of microcells has increased the number of handovers especially in metropolitan cities. Consequently further stress is exerted on existing CAC schemes to maintain the Quality of Service (QoS). In this paper we present new CAC algorithms based on dynamic allocation of channels to multiple input traffic streams. In this context two CAC schemes are proposed; IPG (Independent DT Queue priority, Pre-emptable DS priority, Guard Channel priority) and ITPG (Independent DT Queue priority, Timeout handover DS queuing Priority, Pre-emptable DS priority, Guard Channel priority). This scheme provides differentiated admission to various delay sensitive (DS) and delay tolerant (DT) traffic streams for both handover request (HOR) and new call request (NCR) according to current load intensity. The scheme provides an effective pre-emption priority in order to decreases forced handover failure probability. Service nature and customer behavior was considered to lay down the different levels of priorities that were assigned at different stages of the CAC scheme in order to achieve optimal QoS for urban area (metropolitan) cell. The simulation results demonstrate the improved QoS under various traffic scenarios.
Single‐ and Multiple‐Dose Pharmacokinetics of Pirfenidone, an Antifibrotic Agent, in Healthy Chinese Volunteers
Authors: Shi Shaojun , Wu Jianhong , Chen Huating , Chen Hui , Wu Jun , Zeng Fandian
Published: September 2007

A randomized, dose‐escalating study evaluated the pharmacokinetics of single and multiple oral doses of pirfenidone, a promising antifibrotic agent, in 48 healthy Chinese volunteers. The effects of sex and food on the pharmacokinetics of pirfenidone were also evaluated. Pharmacokinetics was determined from serial blood samples obtained up to 12 hours after administration of single 200‐, 400‐, or 600‐mg doses of pirfenidone and after multiple doses of 400 mg administrated 3 times daily (tid). Plasma levels of pirfenidone and areas under the curve were found to be proportional to dose. Pirfenidone was rapidly absorbed (tmax = 0.33–1 hours) and cleared (t1/2 = 2–2.5 hours). Pharmacokinetic parameters after multiple doses were similar to those after single doses. Food had a significant effect (P < .01) on the extent of absorption (AUC0‐∞ = 37.4 ± 15.4 mg·h/L [fed] vs 46.6 ± 16.8 mg·h/L [fasted]), rate of absorption was considerably (P < .001) prolonged (tmax = 1.5 ± 0.4 hours [fed] vs 0.7 ± 0.2 hours [fasted]), and peak concentrations were significantly (P < .001) decreased (Cmax = 9.2 ± 2.9 mg/L [fed] vs 13.0 ± 1.8 mg/L [fasted]). No significant sex differences were noted for pharmacokinetic variables. Pirfenidone was well tolerated. These results support a tid regimen of pirfenidone for the management of idiopathic pulmonary fibrosis. Concomitant intake of food will reduce the rate and extent (about 20%) of absorption, which is associated with better tolerability of pirfenidone.
The Emotional Underpinnings of Male Fidelity in Imperial China
Authors: Hinsch Bret
Published: September 2007

Although most studies of marital fidelity in imperial China have stressed the loyalty of wives to husbands, we should not ignore the complementary phenomenon of male fidelity. The affection and faithfulness of men toward their wives were repeatedly expressed as both ideal and norm. Various media conveyed messages of male fidelity, and each genre depicts men's behavior somewhat differently. Throughout time, rich traditions of discourse on the subject emerged, and discussions of male fidelity became increasingly subtle and sophisticated. Research on male fidelity provides fresh insights into the intimate emotional bonds underpinning Chinese family relations. This is an important subject of study, because it constitutes a subjective personal side to traditional Chinese ideas about marriage that allows us to get beyond public institutions and official ideology. In addition, the beliefs surrounding male fidelity provide useful background information for understanding some of the complex motivations underpinning female chastity.
Cerebrospinal fluid proteome profile in multiple sclerosis
Authors: Lehmensiek V. , Süssmuth SD , Tauscher G. , Brettschneider J. , Felk S. , Gillardon F. , Tumani H.
Published: September 2007

Cerebrospinal fluid (CSF) proteins may provide important information about the pathomechanisms present in multiple sclerosis (MS). Although diagnostic criteria for early MS are available, there is still a need for biomarkers, predicting disease subtype and progression to improve individually tailored treatment. Using the two-dimensional difference gel electrophoresis (2-D-DIGE) technology for comparative analysis, we compared CSF samples from patients with MS of the relapse-remitting type (RRMS, n = 12) and from patients with clinically isolated syndrome (CIS, n = 12) suggestive of a first demyelinating attack with neurologically normal controls. Protein spots that showed more than two-fold difference between patients and controls were selected for further analysis with MALDI-TOF mass spectrometry. Immunoblot analysis was performed to confirm the validity of individual candidate proteins. In RRMS, we identified 1 up-regulated and 10 down-regulated proteins. In CIS, 2 up-regulated and 11 down-regulated proteins were identified. One of these proteins (Apolipoprotein A1) was confirmed by immunoblot. Though the pathophysiological role of these proteins still remains to be elucidated in detail and further validation is needed, these findings may have a relevant impact on the identification of disease-specific markers. Multiple Sclerosis 2007; 13: 840—849. http://msj.sagepub.com
Multiple sclerosis susceptibility and the X chromosome
Authors: Herrera BM , Cader MZ , Dyment DA , Bell JT , DeLuca GC , Willer CJ , Lincoln MR , Ramagopalan SV , Chao M. , Orton S-M. , Sadovnick AD , Ebers GC
Published: September 2007

Multiple sclerosis (MS) is a chronic autoimmune complex trait with strong evidence for a genetic component. A female gender bias is clear but unexplained and a maternal parent-of-origin effect has been described. X-linked transmission of susceptibility has been previously proposed, based on pedigree, association and linkage studies. We genotyped 726 relative pairs including 552 affected sib-pairs for 22 X-chromosome microsatellite markers and a novel dataset of 195 aunt-uncle/niece-nephew (AUNN) affected pairs for 18 markers. Parent-of-origin effects were explored by dividing AUNN families into likely maternal and paternal trait transmission. For the sib-pair dataset we were able to establish exclusion at a λ s = 1.9 for all markers using an exclusion threshold of LOD ≤—2. Similarly for the AUNN dataset, we established exclusion at λAV = 1.9. For the combined dataset we estimate exclusion of λ = 1.6. We did not identify significant linkage in either the sib-pairs or the AUNN dataset nor when datasets were stratified for the presence/absence of the HLA-DRB1*15 allele or for paternal or maternal transmission. This comprehensive scrutiny of the X-chromosome suggests that it is unlikely to harbour an independent susceptibility locus or one which interacts with the HLA. Complex interactions including epigenetic ones, and masking by balanced polymorphisms are mechanisms not excluded by the approach taken. Multiple Sclerosis 2007; 13 : 856—864. http://msj.sagepub.com
The nature of caregiving in multiple sclerosis: development of the caregiving tasks in multiple sclerosis scale
Authors: Pakenham K.I.
Published: September 2007

Caregivers of persons with multiple sclerosis (MS) engage in many caregiving tasks and spend considerable time on these activities with such caregiving being of immense social and economic value. However, the lack of empirically derived psychometrically sound instruments for measuring caregiving tasks has hampered progress in this field. This study aimed 1) to examine the dimensional and psychometric structure of the Caregiving Tasks in MS Scale (CTiMSS), and 2) to examine caregiver and care recipient correlates of caregiving tasks. Participants were 232 caregivers of persons with MS and their care recipients. Questionnaires were completed at Time 1 and 12 months later (Time 2). Factor analyses showed that the CTiMSS could be represented by a single dimension or four caregiving domains: Instrumental Care, Activities of Daily Living Care, Psycho-emotional Care, Social-practical Care. The CTiMSS factors were psychometrically sound and evidenced differential relations with most caregiver and care recipient characteristics and predicted changes in adjustment over 12 months. Findings delineate the key dimensions of MS caregiving and show the differential links between caregiving task domains and caregiver and care recipient characteristics. Results provide preliminary reliability and validity data on the first published measure of caregiving tasks in MS. Such an instrument is important for theory building, across study comparisons and the development of services. Multiple Sclerosis 2007; 13: 929—938. http://msj.sagepub.com
Grounded theory sampling: `whole' family research
Authors: Neill Sarah J.
Published: September 2007

This paper presents an analysis of the theory and reality of sampling `whole' families for a grounded theory research project exploring child and family management of acute childhood illness at home. Initial access to families for child health research projects can be difficult given the recent negative image of research involving children portrayed by the media. Once access to families is secured, whole family access may be prevented due to internal family dynamics in a society with rising rates of divorce and remarriage. Ethical issues also arise: individual family members may feel coerced into participating by other family members; if family members are interviewed separately researchers need to be particularly careful to maintain confidentiality; with children extra time is needed to facilitate rapport and an understanding of the researcher role. There is also a tension for children in the early stages of a research relationship between feeling safe and personal privacy. Theoretical sampling may direct data collection with wider members of the family, but it may not be possible to access these people. `Whole' family research may be the aim, but inevitably each family will decide, collectively and individually, how this is determined.
A phenomenological exploration of the patient learning J experiences of 16—19 year-old women accessing a young people's rheumatology service in the UK
Authors: Hutchinson Elizabeth , Hall Carol
Published: September 2007

Sustaining the needs of people with chronic illness is a challenge facing health and social care services. Patients' knowledge about their disease can impact on improving the management of their care and may offer opportunity for increasing support (Department of Health, 2000, 2001, 2003, 2005). This small phenomenological enquiry sought to understand how six young women aged between 16 and 19 years experienced learning about their rheumatological illness, and their preferred learning options relating to treatment and management. Data was collected through the use of semi-structured interviews. Interviews were analysed using a modified version of Colaizzi's seven stage process (Hantikainen and Kappeli, 2000). Findings offer insight into perceived health knowledge needs of young women with rheumatological illness in the UK. Data gathered indicated that communication was of concern for the sample, particularly within lay environments such as schools, work and home. Opportunities for service improvement are discussed within the context of existing evidence, including tailoring of materials for young people, and development of services that facilitate effective communication. The involvement of `experienced patients' may be beneficial in facilitating self-care management of young women with rheumatological disease.
An exploratory study into nurses' understanding and knowledge of children and young people with eczema
Authors: Gill Steve , Coad Jane
Published: September 2007

This is an exploratory research project that enquires into the capabilities of three different groups of paediatric-trained nurses to meet the needs of children and young people with eczema, one of the commonest of chronic conditions of childhood. Data methodology included vignettes and associated questionnaire, which was used with three groups of nurses working with children and young people: students; qualified children's nurses and school nurses. The findings indicated a low level of dermatology nursing knowledge about basic skin care and that some nurses even appeared to avoid those who were disfigured by skin disease. It also raises some questions about whether the disfiguring nature of skin disorders such as eczema can affect a nurse's decision-making ability.
An evaluation of an inter-disciplinary constipation clinic for childhood constipation
Authors: Devitt Patric , Thornley Elizabeth , Hinks Melanie
Published: September 2007

Childhood constipation is a common chronic condition that has considerable implications for both the children who suffer from it and their families. The complex nature of the condition requires an multi-faceted response. Recognising this, a multidisciplinary clinic was set up in a hospital in the north-west of England. This article reports the process and outcomes of an evaluation of the clinic. The evaluation combined data from a number of sources and both qualitative and quantitative data were collected. Questionnaires and one-to-one interviews were employed. The sample included both service users and medical consultants. Families reported on the impact that the condition had on their perceived quality of life. The multidisciplinary `joined-up' approach was valued by both service users and medical consultants.
Drug using parents: an exploration of family focused support from health professionals
Authors: Moy Maxine , Bayliss Jane , Firth Colin , Leggate Joyce , Wood Russell
Published: September 2007

The objective of this paper was to explore the challenges identified by four health professionals working with families who misuse drugs in relation to family parenting responsibilities. Participants included a midwife, a public health nurse, a general practitioner and a specialist addiction nurse. The paper explored self reflections by the participants of their practice in a primary care setting. Three challenges were identified: family focused care; ethical considerations; and the need for a supported learning environment. The paper proposes consideration of appropriately funded, mandatory joint training supported through a learning organisation approach within the NHS.
Conducting focus groups with children and young people: strategies for success
Authors: Gibson Faith
Published: September 2007

Focus groups have become a popular and widely used method in qualitative research across the diversity of healthcare. Their use however has been applied mainly to research with adult participants. Only in the last 10 years have we witnessed an expansion in their use with children and young people. This paper describes briefly the characteristics of focus groups before focusing exclusively on the methodological and practical concerns when conducting focus groups with children and young people. Focus groups require considerable preparation and skill to run. Strategies are detailed in this paper to achieve two important outcomes, successful data collection and a positive experience for participants.
NOTCH1 mutation can be an early, prenatal genetic event in T-ALL
Authors: Eguchi-Ishimae Minenori , Eguchi Mariko , Kempski Helena , Greaves Mel
Published: September 2007

NOTCH1 mutations are common in T-lineage acute lymphoblastic leukemia (T-ALL). Twin studies and retrospective screening of neonatal blood spots provide evidence that fusion genes and other chromosomal abnormalities associated with pediatric leukemias can originate prenatally. Whether this is also the case for NOTCH1 mutations is unknown. Eleven cases of T-ALL were screened for NOTCH1 mutations and 4 (36%) had mutations in either the heterodimerization (HD) or proline glutamic acid/serine/threonine (PEST) domains. Of these 4, 3 could be amplified by mutation-specific polymerase chain reaction primers. In one of these 3, with the highest sensitivity, NOTCH1 mutation was detected in neonatal blood spots. In this patient, the blood spot was negative for SIL-TAL1 fusion, present concomitant with NOTCH1 mutation, in the diagnostic sample. We conclude that NOTCH1 can be an early or initiating event in T-ALL arising prenatally, to be complemented by a postnatal SIL-TAL1 fusion.
Minireview: The Circadian Clockwork of the Suprachiasmatic Nuclei—Analysis of a Cellular Oscillator that Drives Endocrine Rhythms
Authors: Maywood Elizabeth S. , O’Neill John S. , Chesham Johanna E. , Hastings Michael H.
Published: September 2007

The secretion of hormones is temporally precise and periodic, oscillating over hours, days, and months. The circadian timekeeper within the suprachiasmatic nuclei (SCN) is central to this coordination, modulating the frequency of pulsatile release, maintaining daily cycles of secretion, and defining the time base for longer-term rhythms. This central clock is driven by cell-autonomous, transcriptional/posttranslational feedback loops incorporating Period (Per) and other clock genes. SCN neurons exist, however, within neural circuits, and an unresolved question is how SCN clock cells interact. By monitoring the SCN molecular clockwork using fluorescence and bioluminescence videomicroscopy of organotypic slices from mPer1::GFP and mPer1::luciferase transgenic mice, we show that interneuronal neuropeptidergic signaling via the vasoactive intestinal peptide (VIP)/PACAP2 (VPAC2) receptor for VIP (an abundant SCN neuropeptide) is necessary to maintain both the amplitude and the synchrony of clock cells in the SCN. Acute induction of mPer1 by light is, however, independent of VIP/VPAC2 signaling, demonstrating dissociation between cellular mechanisms mediating circadian control of the clockwork and those mediating its retinally dependent entrainment to the light/dark cycle. The latter likely involves the Ca2+/cAMP response elements of mPer genes, triggered by a MAPK cascade activated by retinal afferents to the SCN. In the absence of VPAC2 signaling, however, this cascade is inappropriately responsive to light during circadian daytime. Hence VPAC2-mediated signaling sustains the SCN cellular clockwork and is necessary both for interneuronal synchronization and appropriate entrainment to the light/dark cycle. In its absence, behavioral and endocrine rhythms are severely compromised.
Single dent within elastohydrodynamic contact - comparison between experimental and numerical results
Authors: Křupka I , Hartl M , Urbanec L , Čermák J
Published: September 2007

Behaviour of a single dent within elastohydrodynamically lubricated contact has been observed both experimentally and numerically. The dent on the contact surface of the ball was artificially produced by a Rockwell indenter and the lip of raised metal around the perimeter of the depression was reduced by subsequent hand-polishing. Thin film colorimetric interferometry has provided precise film thickness data through the evaluation of chromatic interferograms. Obtained results are compared with data provided by a numerical solver for the contact problem that was developed and tested. From the results for different contact parameters it can be stated that good agreement between the numerical and experimental data was reached.
Effects of surface texture on journal-bearing characteristics under steady-state operating conditions
Authors: Tala-Ighil N , Maspeyrot P , Fillon M , Bounif A
Published: September 2007

Developments in microscopy have a profound effect on the resurgence of tribological applications at the microscopic level. Using surfaces with controlled microgeometry may prove an effective approach to improving bearing performance. It is consequently of interest to study the lubrication of journal bearing systems taking into consideration the effect of surface geometry design. A numerical approach is used in the analysis of texture effects on bearing characteristics. The results from investigating the performance of bearing surfaces with spherical dimple textures suggest that contact characteristics such asminimumfilm thickness, maximumpressure, axial oil film flow, and friction torque may be improved through an appropriate surface texture geometry and appropriate textures distribution on the contact surface. The main purpose of our work is to model and understand the evolution of journal-bearing characteristics with textures. A rigorous methodology is recommended. The work is divided into two steps. The first one serves to quantify the evolution of the characteristics with the texture parameters and to deduce their optimized values. The second step enhance the performance of the journal bearing by progressively taking into account the optimized values of texture parameters, especially the textures disposition.
Multi-body wave analysis of axially elastic rod systems
Authors: Keskinen E , Kuokkala V-T , Vuoristo T , Martikainen M
Published: September 2007

Axially elastic rods are basic machine elements in hydraulic hammers, pilers, and percussive drills. The problem to analyse the motion history of such mechanisms is a very complex one, because the rods are simultaneously in large-amplitude axial motion superimposed with a small-amplitude elastic wave motion. The wave motion experiences division to reflected and transmitted components at each rod-rod interface depending on the current boundary stiffness. The wave motion in each rod can be computed by finite elements or, alternatively, in space of semidefinite eigenfunctions. The feasibility of these methods in solving wave propagation problems in multi-rod systems with non-linearly behaving rod-rod interfaces has been investigated and evaluated. The object of the experimental case study is a classical Hopkinson split bar apparatus used in experimental analysis of material response to shock pulses. Another example representing a pile hammering system evaluates the computational performance of the proposed approaches in long-termsimulation of a complete work process.
Multi-physics analysis of valve train systems: From system level to microscale interactions
Authors: Teodorescu M , Kushwaha M , Rahnejat H , Rothberg S J
Published: September 2007

The paper highlights a holistic, integrated, and multi-disciplinary approach to design analysis of valve train systems, referred to as multi-physics. The analysis comprises various forms of physical phenomena and their interactions, including large displacement inertial dynamics, small amplitude oscillations due to system compliances, tribology, contact mechanics, and durability at the cam-tappet contact. Therefore, it also represents a multi-scale investigation, where the phenomena can be investigated at system level and referred back to underlying causes at subsystem or component level, in other words, implications of an event at microcosm can be ascertained on the overall system performance. This approach is often referred to in industry as down-cascading and up-cascading. The particular case reported here to outline the merits of this approach concerns a four-stroke single-cylinder engine. This promotes a system approach to engineering analysis for integrated noise, vibration, and harshness, durability and frictional assessment (efficiency). Experimental validation is provided with a motored test rig, using laser doppler vibrometry.
Noise reduction and efficiency improvements via Clatter and Rattle Noise Free (CARF-)Transmissions
Authors: Novak W , Kiefer S , Bertsche B , Stockmeier M , Ryborz J , Doĝan S N
Published: September 2007

Clatter and rattle noise is an increasing challenge for the development of low-noise transmissions. Efforts to reduce fuel consumption and exhaust emissions of combustion engines combined with a decrease of the idle speed cause increasing cyclic irregularities within modern drivelines, which result in an increasing clatter and rattle noise.

Numerous external and internal measures for the reduction of clatter and rattle noise propensity have been developed; however, only a few were applied to series products. This article publishes a potential measure for this noise reduction.

New grounds were broken in the field of clatter and rattle noise free automotive transmissions by decoupling all gears which are not in the power flow. In addition, a reduction of drag torque is one of the results of this measure which leads to an enhanced efficiency. On the basis of a patented solution (CARF-Transmission), the clatter and rattle noise free transmission is presented as well as a derived development.
Is arthroscopic surgery for stabilisation of chronic shoulder instability as effective as open surgery?
Authors: Hobby J. , Griffin D. , Dunbar M. , Boileau P.
Published: September 2007

A systematic search of the literature published between January 1985 and February 2006 identified 62 studies which reported the results of arthroscopic procedures for chronic anterior shoulder instability or comparisons between arthroscopic and open surgery. These studies were classified by surgical technique and research methodology, and when appropriate, were included in a meta-analysis.

The failure rate of arthroscopic shoulder stabilisation using staples or transglenoid suture techniques appeared to be significantly higher than that of either open surgery or arthroscopic stabilisation using suture anchors or bio-absorbable tacks. Arthroscopic anterior stabilisation using the most effective techniques has a similar rate of failure to open stabilisation after two years.
Treatment of haematogenous pyogenic vertebral osteomyelitis by single-stage anterior debridement, grafting of the defect and posterior instrumentation
Authors: Sundararaj G. D. , Babu N. , Amritanand R. , Venkatesh K. , Nithyananth M. , Cherian V. M. , Lee V. N.
Published: September 2007

Anterior debridement, grafting of the defect and posterior instrumentation as a single-stage procedure is a controversial method of managing pyogenic vertebral osteomyelitis. Between 1994 and 2005, 37 patients underwent this procedure at our hospital, of which two died and three had inadequate follow-up. The remaining 32 were reviewed for a mean of 36 months (12 to 66). Their mean age was 48 years (17 to 68). A significant pre-operative neurological deficit was present in 13 patients (41%). The mean duration of surgery was 285 minutes (240 to 360) and the mean blood loss was 900 ml (300 to 1600). Pyogenic organisms were isolated in 21 patients (66%). All patients began to mobilise on the second post-operative day. The mean hospital stay was 13.6 days (10 to 20). Appropriate antibiotics were administered for 10 to 12 weeks. Early wound infection occurred in four patients (12.5%), and late infection in two (6.3%).

At final follow-up, the infection had resolved in all patients, neurological recovery was seen in ten of 13 (76.9%) and interbody fusion had occurred in 30 (94%). The clinical outcome was excellent or good in 30 patients according to Macnab’s criteria.

This surgical protocol can be used to good effect in patients with pyogenic vertebral osteomyelitis when combined with appropriate antibiotic therapy.
Twentieth-century survival from osteosarcoma in childhood
Authors: Foster L. , Dall G. F. , Reid R. , Wallace W. H. , Porter D. E.
Published: September 2007

We have reviewed the data from our regional Bone Tumour Registry on patients with osteosarcoma diagnosed between 1933 and 2004 in order to investigate the relationship between survival and changes in treatment. There were 184 patients with non-metastatic appendicular osteosarcoma diagnosed at the age of 18 or under. Survival was calculated using Kaplan-Meier curves, and multivariate analysis was performed using the Cox regression proportional hazards model.

The five-year survival improved from 21% between 1933 and 1959, to 62% between 1990 and 1999. During this time, a multi-disciplinary organisation was gradually developed to manage treatment. The most significant variable affecting outcome was the date of diagnosis, with trends in improved survival mirroring the introduction of increasingly effective chemotherapy. Our experience suggests that the guidelines of the National Institute for Clinical Excellence on the minimum throughput of centres for treatment should be enforced flexibly in those that can demonstrate that their historical and contemporary results are comparable to those published nationally and internationally.