bluuebunny/crossref_metadata_2025 huggingface dataset:
Oral L-arginine supplementation in cystic fibrosis patients: a placebo-controlled study
Authors: Grasemann H. , Grasemann C. , Kurtz F. , Tietze-Schillings G. , Vester U. , Ratjen F.
Published: January 2005

Exhaled nitric oxide (eNO) is decreased in cystic fibrosis (CF). The effect of oralL-arginine, the precursor of enzymatic nitric oxide (NO) formation, on airway NO in patients with CF was studied.

In a pilot study, oralL-arginine was given in a single dose of 200 mg·kg−1body weight to eight healthy controls and eight CF patients. Subsequently, the sameL-arginine dose was given to 10 patients with CF (five females)t.i.d.for 6 weeks in a randomised double-blind placebo-controlled crossover study.

A single dose of oralL-arginine resulted in a 5.5-fold increase ofL-arginine in plasma and a 1.3-fold increase ofL-arginine in sputum after 2 h. Maximum eNO, within 3 h ofL-arginine intake, increased significantly in both CF patients (5.4±2.1 ppbversus8.3±3.5 ppb) and controls (18.0±8.1 ppbversus26.4±12.3 ppb). Supplementation ofL-arginine for 6 weeks resulted in a sustained increase in eNO compared to placebo (9.7±5.7 ppbversus6.3±3.1 ppb). An effect ofL-arginine supplementation on forced expiratory volume in one second was not observed.

These data indicate that airway nitric oxide formation in cystic fibrosis patients can be augmented with oralL-arginine supplementation.
Annual risk of infection withMycobacterium tuberculosis
Authors: Rieder H.
Published: January 2005

The average annual risk of infection withMycobacterium tuberculosisis a calculated average from an observed prevalence of infection, approximating the incidence of infection. It has the potential to be informative about the extent of transmission in a community. Where serial surveys are available, secular trends in transmission might be ascertained. The prerequisite for calculating the average annual risk is the successful determination of the prevalence of infection. Difficulties arising with tuberculin skin-test surveys include logistical problems in sampling a representative portion of the population. Therefore, a compromise assesses the prevalence of infection among school children as an indicator of transmission in the community at large. The utilisation of tuberculin surveys is further compounded by the unpredictable specificity of the tuberculin skin test and, thus, the predictive value of a positive test result. Statistical approaches using mixture analysis may overcome this problem to some extent, but the experience is limited. Cytokine-derived assays, such as the interferon-γ release assays, are promising in providing higher specificity, but they require venepuncture.
Flow limitation and dynamic hyperinflation: key concepts in modern respiratory physiology
Authors: Calverley P. M. A. , Koulouris N. G.
Published: January 2005

Fashions in ideas, like clothes, come and go. From approximately 1950–1980, physiological research was seen as the key discipline in understanding lung disease and was at the cutting edge of pulmonary science. Subsequently, its importance has been down played amid a widely accepted but unfounded assumption that we now have a perfect working understanding of the physiological behaviour of the respiratory system in health and disease. Although it seems improbable that completely new disciplines within respiratory physiology will emerge with fundamentally different ways of describing the mechanical or gas exchanging function of the lung, advances in computing and new observations in disease have highlighted previously unsuspected physiological abnormalities that have changed the way we view lung disease and the interface between disordered lung mechanics, symptomatology and disability.

This is especially true for the two related physiological concepts of expiratory flow limitation and dynamic hyperinflation, which are now being taken from the physiological laboratory to the bedside with dramatic effect. Each arises from well-established theoretical and practical observations first made 40 yrs ago and now adapted to a range of settings, particularly in the field of obstructive lung disease. This review focuses on how these conditions are defined and assessed and what evidence there is that they might be important in lung disease.
Asthma: prevalence and cost of illness
Authors: Stock S. , Redaelli M. , Luengen M. , Wendland G. , Civello D. , Lauterbach K. W.
Published: January 2005

The purpose of this study was to estimate the prevalence and cost of illness of asthma in Germany by retrospectively analysing routine health insurance data.

This analysis investigated claims data from all insured persons of six large sickness funds. Insurants with asthma were identifiedviathe International Classification of Diseases (ninth revision) diagnosis and the Anatomical Therapeutic Chemical Classification System Code for regular medication prescriptions. Costs for hospital care, medication and sick benefit were taken from claims data. Costs for rehabilitation, premature death and early retirement were estimated using the human capital approach and data from national statistics.

Prevalence of asthma in the German statutory health insurance was 6.34%. Total costs for asthma, including direct and indirect costs, were calculated at \#8364;2.74 billion during 1999.

The prevalence of asthma in the German statutory health insurance has previously been estimated to be 4–6%. The results of this large study show the prevalence of asthma in the German social insurance system to be ∼6%. The study also indicates that there is room for substantial savings in the German social insurance system, with indirect costs amounting to 74.8% of total costs and payment of sick benefits through the sickness funds amounting to 58.3% of indirect costs. These costs may be reduced with better asthma control in patients.
The respiratory effects of occupational polypropylene flock exposure
Authors: Atis S. , Tutluoglu B. , Levent E. , Ozturk C. , Tunaci A. , Sahin K. , Saral A. , Oktay I. , Kanik A. , Nemery B.
Published: January 2005

The present study evaluated the possible effects of exposure to polypropylene flock on respiratory health and serum cytokines in a cross-sectional study of workers from a plant in Turkey.

A total of 50 polypropylene flocking workers were compared to a control group of 45 subjects. All subjects filled out a respiratory questionnaire and underwent a physical examination, a chest radiograph and pulmonary function testing, including single breath carbon monoxide diffusing capacity (DL,CO). Serum interleukin-8 (IL-8) and tumour necrosis factor-alpha (TNF-α) were measured. Additionally, high resolution computed tomography (HRCT) of the chest was performed in 10 exposed workers with lowDL,CO.

Work-related respiratory symptoms were reported in 26% of the exposed subjects and in 13.3% of the controls. Logistic regression analysis showed that the risk of respiratory symptoms increased 3.6 fold in polypropylene flocking workers when compared to controls. Parameters of the study group, including per cent predicted: forced vital capacity, forced expiratory volume in one second, forced mid-expiratory flow 25–75% andDL,CO, were significantly lower than in controls. Multivariate analyses showed that being a polypropylene flocking worker was a predictive factor for impairment of pulmonary function. Serum IL-8 and TNF-α levels were increased in the study group compared with the controls. HRCT revealed peribronchial thickening and diffuse ground glass attenuation in some subjects.

The present study suggests the presence of subtle or the beginning of interstitial lung disease in these polypropylene flocking workers.
Pulmonary fibrosis in an individual occupationally exposed to inhaled indium-tin oxide
Authors: Homma S. , Miyamoto A. , Sakamoto S. , Kishi K. , Motoi N. , Yoshimura K.
Published: January 2005

Despite the increasing industrial use of indium-tin oxide (ITO) to manufacture flat-panel displays, such as liquid-crystal displays or plasma display panels for televisions, little is known about the potential health hazard induced by occupational exposure to indium compounds.

The current study describes a case of fibrotic lung disease that developed after a 4-yr exposure to ITO. The pathology of the lung demonstrated pulmonary fibrosis with the presence of cholesterol granulomas.

In conclusion, more attention needs to be paid to the possible toxic effects of indium compounds, and maximum healthcare measures should be taken to protect industry workers from these toxicities.
Cardiopulmonary effects of iloprost in experimental acute lung injury
Authors: Dembinski R. , Brackhahn W. , Henzler D. , Rott A. , Bensberg R. , Kuhlen R. , Rossaint R.
Published: January 2005

Iloprost, a prostacyclin analogue with a prolonged plasma half-life has beneficial effects in chronic pulmonary hypertension, whereas the effects in acute lung injury (ALI) are unknown. The present study was performed to evaluate the cardiopulmonary effects of iloprost in experimental ALI.

ALI was induced in 18 pigs by repeated lung lavage. Animals were randomised to controls,i.v.or inhaled iloprost for 15 min. Haemodynamics, gas exchange and ventilation–perfusion distribution were measured at the end of iloprost application and after 1 and 2 h.

As a short-term effect, bothi.v.and inhaled iloprost significantly decreased pulmonary artery pressure without major effects on gas exchange or systemic haemodynamics. After 1 and 2 h, a reduction of pulmonary hypertension was no longer present. As a long-term effect, inhaled, but noti.v., iloprost decreased pulmonary shunt and significantly improved gas exchange after 1 and 2 h.

In conclusion, the single application of iloprost revealed short-term pulmonary vasodilation without other major cardiopulmonary effects. However, inhaled iloprost improved gas exchange due to a decrease of pulmonary shunt as a long-term effect, possibly as a result of a reduction of lung oedema formation.
Altered AP-1/Ref-1 redox pathway and reduced proliferative response in iNOS-deficient vascular smooth muscle cells
Authors: Chyu Kuang-Yuh , Dimayuga Paul C , Zhao Xiaoning , Nilsson Jan , Shah Prediman K , Cercek Bojan
Published: January 2005

We previously reported that injury-induced medial vascular smooth muscle cell (VSMC) proliferation and neointima formation in carotid arteries of inducible nitric oxide synthase knockout (iNOS KO) mice were significantly reduced compared with wild type (WT). However, the molecular pathway underlying such differences is not known. In this in vitro study, we discovered that the AP-1/Ref-1/thioredoxin signaling pathway is altered in aortic VSMC from iNOS KO mice, which leads to reduced growth response when compared with aortic VSMC from WT mice. After equal initial seeding, the cell number after 7 days in serum medium was less in iNOS KO cells compared with WT VSMC (1.2-0.6-105 vs 3.2-1.1-105; p < 0.05). Significantly more iNOS KO cells remained in the G0/G1 phase compared with WT cells after 24-h serum treatment (82.6-13.7% vs 62.3-14.6%; p < 0.05) by cell-cycle analysis. Nuclear PCNA expression was also less in the iNOS KO cells, which was not affected by exogenous NO or superoxide. Superoxide generation after 24-h serum stimulation was less in the iNOS KO cells compared with WT cells. After 30-min serum stimulation, AP-1 DNA binding was reduced and a lack of increase in nuclear c-Jun protein was observed in iNOS KO VSMC. RT-PCR analysis confirmed a lack of inducible c-Jun mRNA after serum stimulation in the KO cells. In addition, KO cells had less nuclear reducing factor-1 (Ref-1) and serum-inducible thioredoxin protein expression. Reduced proliferative response of iNOS KO VSMC to serum treatment is associated with altered AP-1/Ref-1/thioredoxin pathway activation.
Lack of an association between angiotensin converting enzyme gene polymorphism and peripheral arterial occlusive disease
Authors: Karagiannis Asterios , Balaska Katerina , Tziomalos Konstantinos , Gerasimidis Thomas , Karamanos Dimitrios , Papayeoryiou Athanasios , Zamboulis Chrysanthos
Published: January 2005

Numerous factors have been reported to influence the pathogenesis of atherosclerosis. The angiotensin I converting enzyme (ACE) gene is a candidate gene for atherosclerotic-related disease. In the present study, the association between the polymorphism of the ACE gene and peripheral arterial occlusive disease (PAOD) was investigated. Using polymerase chain reaction techniques, 100 patients (age 66.7-7.7 years) with PAOD and 100 age-matched controls were divided into the three ACE genotypes: II, ID and DD (Insertion I and Deletion D). There was no evidence of any association between ACE gene polymorphism and the presence of PAOD (odds ratio 0.759; 95% confidence interval 0.418-1.377). These results indicate an absence of association between DD genotype and PAOD. Further evaluation in a larger population study is required to examine the possibility of an increased risk of PAOD in DD homozygotes.
Treating Tobacco Dependence: State of the Science and New Directions
Authors: Lerman Caryn , Patterson Freda , Berrettini Wade
Published: January 2005

Despite almost two decades of intensive tobacco control efforts, nearly one quarter of Americans continue to smoke. The two United States Food and Drug Administration–approved medications used to treat tobacco dependence, bupropion and nicotine replacement therapy, are effective for only a fraction of smokers. Investigations of medications approved for affective disorders and other forms of substance abuse, such as fluoxetine and naltrexone, have yielded mixed results as tobacco dependence treatments. A particular challenge in tobacco dependence treatment is the development of effective approaches for smokers with unique needs, such as cancer patients and pregnant women. Despite new developments in these areas, significant gaps in knowledge and practice remain. Basic research in the neurobiologic and genetic basis of nicotine dependence offers promise for the development of novel and more effective treatment approaches. For example, emerging research in pharmacogenetics explores how genetic variation in drug-metabolizing enzymes and drug targets modifies response to pharmacotherapy. These discoveries could someday help practitioners to individualize the type, dosage, and duration of tobacco dependence treatment based on genotype, and maximize the efficacy.
Cancer Prevention: A Global Perspective
Authors: Stewart Bernard W. , Coates Alan S.
Published: January 2005

This review will be restricted to measures aimed at primary prevention of cancer; reduction of the death rate through screening will not be covered. In many instances, cancer prevention is just one outcome of the benefits of good health practices, which may also benefit cardiovascular, lung, infectious, and metabolic diseases. Thus, reducing tobacco smoking will bring benefits in heart disease, neonatal and maternal health, stroke, and peripheral vascular disease as well as a variety of cancers, while dietary advice appropriate to cancer risk reduction will bring benefits in diabetes, stroke, kidney, and heart disease.
Nutritional Interventions in Cancer Prevention
Authors: Taylor Philip R. , Greenwald Peter
Published: January 2005

The first generation of phase III nutritional intervention studies to prevent cancer has been completed. Nearly 150,000 total participants were studied in nine different interventions using randomized, double-blind, placebo-controlled designs that tested whether vitamins and/or minerals, given singly or in combination, could prevent total or site-specific cancer. The primary agents tested include beta-carotene, alpha-tocopherol, selenium, and retinol. This review summarizes the findings from the first generation of human experimental studies that tested micronutrients in the prevention of cancer, discusses lessons learned from these studies, identifies the most promising leads, and describes future prospects in nutritional intervention research.
Prevention of Hormone-Related Cancers: Prostate Cancer
Authors: Parnes Howard L. , Thompson Ian M. , Ford Leslie G.
Published: January 2005

Androgens are known to play an important role in normal prostate development, benign prostatic hyperplasia, established prostate cancer, and in prostate carcinogenesis. However, despite convincing experimental and clinical evidence, the epidemiologic data correlating sex steroid levels with disease risk is inconsistent. More recent work has focused on studies of polymorphisms in germ-line DNA in an effort to develop polygenic models of prostate cancer susceptibility and prognosis. Such models have the potential to aid in the selection of men for specific chemopreventive interventions and to help determine which men with localized prostate cancer are most likely to benefit from aggressive therapy. In this review, we will provide a brief summary of androgen metabolic pathways followed by an assessment of the epidemiology literature addressing the relationship between androgens and prostate cancer. Finally, we will address the two major questions that have arisen in response to the recently published results from the Prostate Cancer Prevention Trial: Who are the best candidates for finasteride chemoprevention, and what are the clinical implications of the high prevalence of prostate cancer that was detected in men with prostate-specific antigen levels in the so-called “normal” range?
Prevention of Hormone-Related Cancers: Breast Cancer
Authors: Dunn Barbara K. , Wickerham D. Lawrence , Ford Leslie G.
Published: January 2005

Carcinogenesis in the breast is a hormonally dependent process. Evidence implicating estrogen as a key breast carcinogen comes from various lines of investigation. Traditional epidemiologic studies demonstrate associations between estrogen exposure, both exogenous and endogenous, and increased breast cancer risk. Ongoing genetic epidemiologic studies also show associations between specific polymorphisms in estrogen-metabolizing genes and risk, albeit inconsistently. The application of these findings to the treatment and, more recently, the prevention of breast cancer has led to the development of agents that either (1) inhibit estrogen action at the estrogen receptor (selective estrogen receptor modulators (SERMs]); or (2) inhibit estrogen-synthesizing enzymes, thereby abrogating synthesis of this hormone (aromatase inhibitors). Large phase III trials have evaluated the ability of such agents to reduce the incidence of breast cancer in women at increased risk of the disease. The National Surgical Adjuvant Breast and Bowel Project (NSABP) P-1: Breast Cancer Prevention Trial (BCPT) demonstrated the superiority of the SERM tamoxifen to placebo in reducing breast cancer risk, leading to the Food and Drug Administration approval of tamoxifen for risk reduction. The implementation of tamoxifen for this indication has not become widespread in clinical practice, however, for a variety of reasons that we discuss. Results from the NSABP Study of Tamoxifen and Raloxifene, which compares the risk-reducing efficacy as well as toxicity of these two SERMs in a similar high-risk population, will be available in the near future. Based on promising data involving reduction of contralateral breast cancer risk in adjuvant studies, several aromatase inhibitors, including letrozole, anastrozole, and exemestane, are being incorporated into trials evaluating their efficacy as preventive agents in women at increased risk.
Cyclooxygenase-2 and Epidermal Growth Factor Receptor: Pharmacologic Targets for Chemoprevention
Authors: Dannenberg Andrew J. , Lippman Scott M. , Mann Jason R. , Subbaramaiah Kotha , DuBois Raymond N.
Published: January 2005

Understanding the mechanisms underlying carcinogenesis provides insights that are necessary for the development of therapeutic strategies to prevent cancer. Chemoprevention, the use of drugs or natural substances to inhibit carcinogenesis, is a rapidly evolving aspect of cancer research. Evidence is presented that cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) are potential pharmacologic targets to prevent cancer. In this paper, we review key data implicating a causal relationship between COX-2, EGFR, and carcinogenesis and possible mechanisms of action. We discuss evidence of crosstalk between COX-2 and EGFR in order to strengthen the rationale for combination chemoprevention, and review plans for a clinical trial that will evaluate the concept of combination chemoprevention targeting COX-2 and EGFR.
Hereditary Cancer Predisposition Syndromes
Authors: Garber Judy E. , Offit Kenneth
Published: January 2005

Cancer genetics is increasingly becoming integrated into the practice of modern medical oncology. The ability to distinguish a growing proportion of the 5% to 10% of all cancers that develop in individuals who have inherited a genetic mutation conferring heightened susceptibility to specific cancers may permit targeted efforts in cancer surveillance and prevention. While these individuals comprise a small proportion of the overall burden of cancer, strategies successful in reducing their remarkable cancer risks may be generalizable to the broader population. In this review, we highlight the most common hereditary cancer syndromes, most attributable to genes inherited in an autosomal dominant manner with incomplete penetrance, and a number of rare syndromes in which particular progress has been made. The prevalence, penetrance, tumor spectrum, and underlying genetic defects are discussed and summarized in a large table in which a more comprehensive enumeration of syndromes is provided.
Role of Meltrin α (ADAM12) in Obesity Induced by High- Fat Diet
Authors: Masaki Megumi , Kurisaki Tomohiro , Shirakawa Kamon , Sehara-Fujisawa Atsuko
Published: January 2005

Meltrin α is a member of the metalloprotease-disintegrin (ADAM) family. In this paper we demonstrate that meltrin α is involved in the development of white adipose tissue. Compared with wild-type mice, meltrin α−/− mice displayed moderate resistance to weight gain induced by a high-fat diet, mainly because of an impaired increase in the number of adipocytes. There was no obvious difference in adipocyte size between wild-type and meltrin α−/− mice, suggesting normal maturation of adipocytes of the latter under a high-fat diet. Embryonic fibroblasts and stromal-vascular cells lacking meltrin α exhibited impaired cell proliferation upon adipogenic stimulation, which was accompanied by moderate defects in adipose differentiation. Addition of culture medium conditioned with wild-type cells in an early phase of adipose differentiation did not restore the defects in the meltrin α−/− cells. These results uncover the involvement of meltrin α in the development of obesity and in adipogenic cell proliferation.
Effects of KiSS-1 Peptide, the Natural Ligand of GPR54, on Follicle-Stimulating Hormone Secretion in the Rat
Authors: Navarro V. M. , Castellano J. M. , Fernández-Fernández R. , Tovar S. , Roa J. , Mayen A. , Barreiro M. L. , Casanueva F. F. , Aguilar E. , Dieguez C. , Pinilla L. , Tena-Sempere M.
Published: January 2005

KiSS-1 was originally identified as a metastasis suppressor gene encoding an array of structurally related peptides, namely kisspeptins, which acting through the G protein-coupled receptor GPR54 are able to inhibit tumor progression. Unexpectedly, a reproductive facet of this newly discovered system has recently arisen, and characterization of the role of the KiSS-1/GPR54 system in the neuroendocrine control of gonadotropin secretion has been initiated. However, such studies have been so far mostly restricted to LH, and very little is known about the actual contribution of this system in the regulation of FSH release. To address this issue, the effects of KiSS-1 peptide on FSH secretion were monitored in vivo and in vitro under different experimental conditions. Intracerebroventricular administration of KiSS-1 peptide significantly stimulated FSH secretion in prepubertal and adult rats. Yet, dose-response analyses in vivo demonstrated an ED50 value for the FSH-releasing effects of KiSS-1 of 400 pmol, i.e. approximately 100-fold higher than that of LH. In addition, systemic (ip and iv) injection of KiSS-1 significantly stimulated FSH secretion in vivo. However, KiSS-1 failed to elicit basal FSH release directly at the pituitary level, although it moderately enhanced GnRH-stimulated FSH secretion in vitro. Finally, mechanistic studies revealed that the ability of KiSS-1 to elicit FSH secretion was abolished by the blockade of endogenous GnRH actions, but it was persistently observed in different models of leptin insufficiency and after blockade of endogenous excitatory amino acid and nitric oxide pathways, i.e. relevant signals in the neuroendocrine control of gonadotropin secretion. In summary, our results extend previous recent observations on the role of KiSS-1 in the control of LH secretion and provide solid evidence for a stimulatory effect of KiSS-1 on FSH release, acting at central level. Overall, it is proposed that the KiSS-1/GPR54 system is a novel, pivotal downstream element in the neuroendocrine network governing gonadotropin secretion.
Growth of surface flaws induced by the environment and machining stresses in unalloyed uranium
Authors: Wallwork A , Burnell G , Morris S , Rowe A , Clarke I , Clayton A
Published: January 2005

Computer modelling techniques are used to predict the distribution of residual stresses in a machined uranium surface. The predictions are used to address the ageing of uranium exposed to inert gas based environments in terms of microcrack initiation and subsequent propagation. Metallographic observations of microcracking are used as the basis for the initial assessment of ageing behaviour.

It is proposed that the near-surface residual stress field produced by machining influences the occurrence of microcracking. It is also suggested that corrosion-induced surface features act as initiation sites for microcracks, which begin to propagate by an environmentally assisted mechanism when the surface features reach a critical depth within the residual stress field of between 5 and 10 μm. However, the majority of the microcracks appear to arrest at about 150 μm. This behaviour is discussed in terms of the predicted threshold stress intensity for crack nucleation, uranium metallurgy, and the possible effects of crack coalescence on growth.
Determination of the relationship between microstructure and constitutive behaviour of nodular cast iron with a unit cell model
Authors: Collini L , Nicoletto G
Published: January 2005

Unit cell models have been proposed to predict the constitutive law and failure of ductile materials with complex microstructures, such as ferritic nodular cast iron and particulate metal matrix composites (PMMCs). The present contribution aims to extend this modelling approach to the prediction of the constitutive response of nodular cast iron with a mixed ferritic/pearlitic matrix. The finite element method is used within the framework of continuum mechanics to carry out the calculations. The effect of some microstructural features, such as graphite volume fraction and ferrite-pearlite ratio of the matrix, on the mechanical performance is determined. The computational results are compared to results obtained in a previous experimental activity on nodular cast irons.
Finite element analysis of the phase transformation effect in residual stresses generated by quenching in notched steel cylinders
Authors: Silva E P , Pacheco P M C L , Savi M. A
Published: January 2005

The determination of residual stresses is an important task in the analysis of the quenching process. Nevertheless, because of the complexity of the phenomenon, many simplifications are usually adopted in the prediction of these stresses for engineering purposes. One of these simplifications is the effect of phase transformation. Many studies analyse residual stresses generated by the quenching process considering a thermoelastoplastic approach, neglecting phase transformation. The present study analyses the effect of austenite-martensite phase transformation during quenching in the determination of residual stresses, comparing two different models: complete (thermoelastoplastic model with austenite-martensite phase transformation) and without phase transformation (thermoelastoplastic model without phase transformation). The finite element method is employed for spatial discretization together with a constitutive model that represents the thermomechanical behaviour of the quenching process. Progressive induction hardening of steel cylinders with semicircular notches is of concern. Numerical simulations show situations where great discrepancies are introduced in the predicted residual stresses if phase transformation is neglected.
Digital image correlation used for mechanical tests on crimped glass wool samples
Authors: Bergonnier S , Hild F , Roux S
Published: January 2005

Mechanical compression and tearing tests are carried out on crimped glass wool samples. The displacement field is determined by using digital image correlation based on images taken at different stages of the mechanical tests. A multi-scale algorithm is used to resolve accurately the fine details of the displacement field. This technique reveals strain heterogeneities and further localization in compression tests well below the peak stress. Crack formations are identified in tearing tests. Reliability and resolution of the displacement and strain fields are validated by using different window sizes in the correlation analysis.
An evaluation of residual stress distribution in welded compact tension specimens using neutron diffraction
Authors: Rading G. O
Published: January 2005

The neutron diffraction technique was used to determine the residual stress field in welded compact tension specimens of the aluminium-lithium alloy AA 2095. The deep penetrating characteristic of neutrons was exploited to evaluate the through-thickness variation in residual stress. Moreover, insight into the redistribution of these stresses was gained by extending a fatigue crack through the residual stress field and re-examining the stress distribution. The specimen without a crack was found to have a high compressive stress (of the order of - 135MPa) ahead of the notch. This rose to a maximum tensile stress of about 50MPa, 22 mm from the notch, followed by a drop to negative values further ahead of the notch. It was observed that the magnitude of the stresses changed on moving into the thickness of the specimen. However, the form of the graph showing stress versus distance ahead of the notch remained unchanged. When fatigue cracks of different lengths were introduced, the magnitude of the stress close to the tip first increased with crack length, before decreasing and then rising again. Nevertheless, the form of the graph remained unchanged and the stress at the crack tip remained compressive. The paper concludes that any study of the response of a component to mechanical loading involving a residual stress field must take these factors (i.e. through-thickness stress variation and stress redistribution) into consideration.
Comparison of the hole-drilling and X-ray diffraction methods for measuring the residual stresses in shot-peened aluminium alloys
Authors: Fontanari V , Frendo F , Bortolamedi Th , Scardi P
Published: January 2005

The incremental blind hole-drilling and the X-ray diffraction methods were used to measure the residual stress field introduced by shot peening in aluminium alloy 6082-T5 plates. Two peening treatments were selected to produce different depth extensions and peak values arising from different extents of plastic deformation in the surface layer. The results are discussed considering the various sources of uncertainty; in addition to the measuring technique, the effects of the surface treatment that usually induces a strong plastic deformation in the surface layer resulting in material work hardening and worsening of the surface morphology were considered. The residual stress profiles determined by the two methods showed quite good agreement for the two conditions, as regards the values both of the compressive peak and of the penetration depth. The present results provide mutual confirmation of the effectiveness of the two methods for the study of this class of materials.
Computational prediction of out-of-plane welding distortion and experimental investigation
Authors: Camilleri D , Comlekci T , Gray T. G. F
Published: January 2005

The main aim of the work was to investigate a simplified finite element simulation of the out-of-plane distortion caused by fusion butt welding. The thermal transient part of the simulation made use of a finite element analysis of the two-dimensional cross-section of the weld joint and the thermoelastic-plastic treatment was based on analytical algorithms describing transverse and longitudinal deformations, leading to predictions of transverse angular deformation and longitudinal contraction force. These results were then applied to a non-linear elastic finite element model to provide predictions of the final angular and overall deformations of the butt-welded plates. The validity of the simulation was investigated via full-scale tests on 4m x 1.4m x 5 mm steel plates, butt welded using a flux-cored Ar-CO2 metal-inert gas process. Thermography and thermocouple arrays were used to validate the thermal transient computations and out-of-plane deformations were measured using displacement transducers for transient deformations and a laser scanning system to measure the profiles of the whole plates before and after welding. The results of six full-scale tests are given and comparison with the simulations shows that the procedure provides good prediction of the angular and overall out-of-plane deformations. Prediction accuracy requires account to be taken of initial shape, gravity loading, and support conditions.
Fatigue life improvement of threaded connections by cold rolling
Authors: Knight M. J , Brennan F. P , Dover W. D
Published: January 2005

Failures in drillstring threaded connections continue to afflict the oil industry at a cost of millions of dollars per year. In an attempt to reduce these failures the industry has generally adopted the fatigue-life-enhancing technique of cold rolling the threaded connections which act as stress concentrations. However, this beneficial process is only specified as optional in the industry standards, and where it is performed there is very little detail provided about this important process. This paper describes full-scale fatigue tests that investigate the cold-rolling process. From the development of cold-rolling equipment and the gathering of fatigue experimental data, several key factors have been identified that influence the operational lifetime of drillstring threaded connections.
On the finite element analysis of contacting bodies using submodelling
Authors: Rajasekaran R , Nowell D
Published: January 2005

The implication of selecting different contact algorithms in solving a contact problem by a submodelling approach is highlighted using the example of a partial slip Cattaneo-Mindlin problem. It is shown that, by employing a penalty formulation, the state of partial slip can be incorrectly predicted as full sliding whereas a Lagrange formulation predicts the correct slip-stick behaviour. The displacements along the centre-line of contact are calculated by analytical approach and compared with finite element results. It is found that the Lagrange multiplier approach predictions match the analytical results well, but prediction by the penalty formulation is sensitive to the slip tolerance selected. It is concluded that care should be exercised while using the penalty formulation for displacement-controlled problems.
A mixed thyroglossal cyst
Authors: Phillips P.S. , Ramsay A. , Leighton S.E.J.
Published: January 2005

The case is described of a boy who presented at age six months with symptoms and signs of a thyroglossal cyst, which seemed to be confirmed by ultrasound findings. The cyst slowly increased in size, and eventually the patient underwent Sistrunk’s procedure at age four years. Histology showed that the cyst was in fact a mixed thyroglossal and dermoid cyst. This casts doubt on the doctrine that thyroglossal cysts and dermoid cysts are anatomically and histologically separate entities, and strengthens the view that these cysts should be more appropriately named ’thyroglossal abnormalities’.
Long-term ventilation of the middle ear using a subannular tympanotomy technique: a follow-up study
Authors: Jassar P. , Coatesworth A. , Strachan D.R.
Published: January 2005

The results of a nine-year series of patients who underwent long-term middle ear ventilation using a tympanotomy technique are presented. The original series of 26 cases was published in 1995. The same series has now expanded to 37 cases, which form the basis of this follow-up study. In contrast to the original series we found a high spontaneous extrusion rate (68 per cent) and in 27 per cent of cases complications necessitated removal of the subannular T tube. In favour of the technique was a low perforation rate after extrusion or removal (eight per cent). Although only nine per cent underwent re-ventilation this is unlikely to represent resolution of the middle ear effusion in the remaining cases.

We conclude that the adverse effects of the subannular tympanotomy technique for long-term ventilation of the middle ear outweigh the benefits when compared with the traditional technique of placing a T tube through a myringotomy incision.
Secondary post-tonsillectomy haemorrhage and informed consent
Authors: Alexander R.J. , Kukreja R. , Ford G.R.
Published: January 2005

This is a prospective incidence study of 250 secondary post-tonsillectomy haemorrhages from a population of 2706 tonsillectomies performed over a seven-year period, which aims to ascertain the incidence and character of post-tonsillectomy secondary haemorrhage. Out of 250 post-tonsillectomy secondary bleeds (9.2 per cent of total; 95 per cent CI = 8.2 per cent – 10.4 per cent), 39 patients had a severe bleed (1.4 per cent; 95 per cent CI = 1.2 per cent – 2.1 per cent). The incidence of secondary tonsillectomy haemorrhage increased with age, peaking at 30–34 years in both men and women (p < 0.001), with no statistically significant difference between the two sexes (p = 0.23). The incidence of serious haemorrhage increases in the older age categories (p = 0.005) but is not influenced by gender (p = 0.50). The majority of secondary tonsillectomy haemorrhages presented between the fourth and seventh day post-operation (69.8 per cent). These results now provide the basis for informed consent for a tonsillectomy in our department.
Subdural haematoma: a complication of cochlear implantation
Authors: Sunkaraneni V.S. , Banerjee A. , Gray R.F.
Published: January 2005

Cochlear implants have transformed the treatment of sensorineural hearing loss. They have few major complications. The authors describe the case of a man fitted with a cochlear implant who suffered a postoperative subdural haematoma. The haematoma is thought to have been caused by bleeding from emissary veins opened by the drill passages used to anchor the sutures for the receiver/stimulator. The authors have abandoned tie down sutures in cochlear implants, preferring an appropriately deep well with squared-off rims, which would secure the implant in place. They have had no further complications of this nature.
Reduction of the incidence and severity of collagen‐induced arthritis by constitutive Nur77 expression in the T cell lineage
Authors: De Silva Swanthri , Han Shuhua , Zhang Xuejun , Huston David P. , Winoto Astar , Zheng Biao
Published: January 2005

Objective

To test the hypothesis that constitutive expression of Nur77 in the T cell lineage will suppress the development and pathogenesis of collagen‐induced arthritis (CIA) and to understand the mechanisms by which Nur77 overexpression influences the arthritogenic response to type II collagen (CII).

Methods

Nur77‐transgenic and wild‐type C57BL/6 mice were immunized with CII and were monitored for the development and severity of arthritis. Pathologic changes were examined by histology and radiography. The effects of Nur77 overexpression on immune responses were evaluated by cytokine production in vitro and serum levels of CII‐specific antibodies. Sensitivity of T cells to apoptosis induction was analyzed in vitro following stimulation with anti‐CD3 monoclonal antibody or glucocorticoid.

Results

The incidence and severity of CIA was significantly decreased in Nur77‐transgenic mice compared with wild‐type controls. Attenuation of the disease was associated with increased apoptosis induction in transgenic T cells and decreased production of CII‐specific IgG2a antibodies in transgenic mice. Overexpression of Nur77 in the T cell compartment did not affect Th1/Th2 cytokine production or balance.

Conclusion

Nur77 overexpression in the T cell lineage attenuates the development and progression of CIA, probably by promoting activation‐induced T cell apoptosis and by inhibiting CII‐specific antibody production.
Oszillierende Weltmodelle versus Urknallmodelle. Das oszillierende Weltmodell Friedmanns, die Ablehnung der Anfangssingularität durch russische Kosmologen und die Zustimmung der katholischen Kirche zur Urknalltheorie Lemaîtres und Hawkings
Authors: Jung Tobias
Published: January 2005

The Russian mathematician and physicist Friedmann and the Belgian priest and physicist Lemaître were the first to consider non‐static world models in the framework of Einstein's general theory of relativity. Friedmann seemed to favour a periodic, oscillating cosmological model. His investigations were taken up by Russian cosmologists in the 1960s. They stated that the singularities present in many of the Friedmann‐Lemaître cosmological models seemed to be artificial and were ascribed to the assumption of a highly symmetric distribution of cosmic matter. Their disapproval of singularities seems to be in accord with Soviet ideological requirements during that time like atheism and dialectic materialism. They had to retract their statements after Hawking had proved his singularity theorems and after the microwave background had been discovered. Hawking followed the line of thought which was initiated by Lemaître in the early 1930s. Lemaître had combined for the first time quantum physics and relativistic cosmology and had developed his idea of the primeval atom, a beginning of the universe in a dense state with just one quantum containing the whole mass of the universe. Pope Pius XII brought together this primeval atom and God as the Creator of the universe and declared in 1951 that big bang cosmology is compatible with the Bible. Not surprisingly Hawking was awarded the Pius XI medal by the Vatican in 1975 for his contributions to big bang cosmology.
A Unified Orbital Model of Delocalised and Localised Currents in Monocycles, from Annulenes to Azabora‐heterocycles
Authors: Soncini Alessandro , Domene Carmen , Engelberts Jeroen J. , Fowler Patrick W. , Rassat André , van Lenthe Joop H. , Havenith Remco W. A. , Jenneskens Leonardus W.
Published: January 2005

Why are some (4n+2)π systems aromatic, and some not? The ipsocentric approach to the calculation of the current density induced in a molecule by an external magnetic field predicts a four‐electron diatropic (aromatic) ring current for (4n+2)π carbocycles and a two‐electron paratropic (antiaromatic) current for (4n)π carbocycles. With the inclusion of an electronegativity parameter, an ipsocentric frontier‐orbital model also predicts the transition from delocalised currents in carbocycles to nitrogen‐localised currents in alternating azabora‐heterocycles, which rationalises the differences in (magnetic) aromaticity between these isoelectronic π‐conjugated systems. Ab initio valence‐bond calculations confirm the localisation predicted by the naïve model, and coupled‐Hartree–Fock calculations give current‐density maps that exhibit the predicted delocalised‐to‐localised/carbocycle–heterocycle transition.
Synthesis of Supramolecular Polymers by Ionic Self‐Assembly of Oppositely Charged Dyes
Authors: Guan Ying , Yu Shu‐Hong , Antonietti Markus , Böttcher Christoph , Faul Charl F. J.
Published: January 2005

A new type of supramolecular polymer was prepared by ionic self‐assembly (ISA) from two oppositely charged dyes; a perylenediimide and a copper–phthalocyanine derivative. Coulomb coupling stabilizes the whole structure, and a combination of charge‐transfer interactions and discotic stacking facilitates the exclusive formation of one‐dimensional polymeric chains. The supramolecular dye‐polymers have a large association constant (2.4×107 L mol−1), high molecular weight, and high mechanical stability. The use of cryo‐transmission electron microscopy (cryo‐TEM) confirmed the existence of extended fibers of width 2.4 nm. Further image analysis revealed slight undulation and faint segmentation of the fibers, and density maxima were observed at a regular interval of 3.6 nm along the fiber axis. The fiber‐like structure (and aggregate of fibers) is also found in the solid state, as shown by the results of mineralization contrasting experiments, atomic force microscopy (AFM), and X‐ray analyses. A structural model is proposed, in which the structural subunits, arranged in a side‐by‐side conformation, form a stacked structure.
Investigation of a tartaric acid‐based linear polyamide and dimer as chiral selectors in liquid chromatography
Authors: Oxelbark Joakim , Gidlund Peter
Published: January 2005

A twin selector for enantioselective liquid chromatography based on O,O′‐bis(dimethyl)benzoyl tartaric diamide was synthesized and compared to commercially available Kromasil CHI‐DMB (O,O′‐bis(dimethyl)benzoyl tartaric diamide). A linear polyamide based on the same tartaric acid derivative was also synthesized, immobilized on silica, and evaluated as stationary phase. The twin selector was immobilized as a brush‐type phase, with similar bonding chemistry as in Kromasil CHI‐DMB. It was shown to exhibit lower resolution power than Kromasil CHI‐DMB. However, retention and separation factors obtained on the respective sorbents were shown to exhibit interdependence. CD spectra of the twin selector give no indication that the respective branches interact in the solvent mixtures employed for chromatography. The linear polyamide showed lower enantioselectivity and higher retention than Kromasil CHI‐DMB. Chirality 17:79–84, 2005. © 2005 Wiley‐Liss, Inc.
Enantioselective synthesis of chiral sulfinates using chiral diamines
Authors: Nakamura Shuichi , Tateyama Motoaki , Sugimoto Hideki , Nakagawa Masaya , Watanabe Yoshihiko , Shibata Norio , Toru Takeshi
Published: January 2005

The reaction of p‐toluenesulfinyl chloride with alcohols in the presence of chiral diamines was examined. Chiral sulfinates were obtained in good yields with enantioselectivity up to 76% ee. Chirality 17:85–88, 2005. © 2005 Wiley‐Liss, Inc.
The FDA perspective on the development of stereoisomers
Authors: De Camp Wilson H.
Published: January 2005

The current regulatory position of the Food and Drug Administration is discussed with regard to the approval of racemates and pure stereoisomers. Circumstances in which stereochemically sensitive analytical methods are necessay to ensure the safety and efficacy of a drug are described. Regulatory guidelines are interpreted for applications for the approval of a pure enantiomer in which the racemate is marketed, for the approval of eitehr a racemate or a pure enantiomer in which neither is marketed, and for clinical investigations to compare the safety and efficacy of a racemate and its enantiomers. Examples of te basis for such regulation are drawn from historical situations (thalidomide, benoxaprofen) as well as currently marketed drugs (arylproionic acids, disopyramide, indacrinone).