bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Metabolic Syndrome on the Development of Cardiovascular Disease in a General Japanese Population
Authors: Ninomiya Toshiharu , Kubo Michiaki , Doi Yasufumi , Yonemoto Koji , Tanizaki Yumihiro , Rahman Mahbubur , Arima Hisatomi , Tsuryuya Kazuhiko , Iida Mitsuo , Kiyohara Yutaka
Published: May 2007

Background and Purpose—

The metabolic syndrome (MetS) is associated with an increased risk of cardiovascular disease (CVD) events in general populations. However, well-designed prospective studies in Asian populations are very limited.

Methods—

We prospectively evaluated a total of 2452 community-dwelling Japanese individuals aged 40 years or older from 1988 to 2002 and examined the effects of MetS defined by the modified National Cholesterol Education Program Adult Treatment Panel III criteria on incident CVD.

Results—

The prevalence of the MetS was 21% in men and 30% in women at baseline. During the follow up, 307 CVD events occurred. Compared with those without MetS, the age-adjusted incidence of CVD (per 1000 person-years) was significantly higher in subjects with the MetS in both men (21.8 versus 11.6,
P
<0.01) and women (12.9 versus 6.5,
P
<0.01). The risk of CVD events was significantly higher even after adjusting for the following confounding factors: age, proteinuria, electrocardiographic abnormalities, serum total cholesterol, smoking habits, alcohol intake, and regular exercise (hazard ratio, 1.86; 95% CI, 1.32 to 2.62 in men and hazard ratio, 1.70; 95% CI, 1.22 to 2.36 in women). The risk of incident CVD was found to increase with the number of components of MetS and became significantly predictive when the number of components reached 3. Similar associations were also observed when CVD was divided into coronary heart disease and stroke.

Conclusions—

Our findings suggest that MetS is a significant risk factor for the development of CVD in the Japanese middle-aged population.
A Pilot Study of Dual Treatment With Recombinant Tissue Plasminogen Activator and Uric Acid in Acute Ischemic Stroke
Authors: Amaro Sergio , Soy Dolors , Obach Víctor , Cervera Álvaro , Planas Anna M. , Chamorro Ángel
Published: May 2007

Background and Purpose—

Uric acid (UA) increases the neuroprotective effects of recombinant tissue plasminogen activator (rt-PA) in experimental ischemia. In patients with stroke, increased UA levels have been linked to better stroke recovery, but the clinical safety of dual administration of UA and rt-PA is unknown.

Methods—

Using a double-blind design, we assessed the safety of exogenous UA in patients with acute stroke treated with rt-PA. Patients were randomized to an intravenous solution of 500 mL of 5% mannitol/0.1% lithium carbonate (vehicle group, n=8) or 500 or 1000 mg of UA (n=16). Safety end points at day 90, lipid peroxidation (serum malondialdehyde), and serum kinetics of UA were established.

Results—

Twenty-four patients with stroke were treated with rt-PA within mean (SD) 133 (35) minutes of clinical onset (admission National Institutes of Health Stroke Scale score mean [SD] 11 [7], age 71 [10.6] years, 71% males). Levels of UA decreased in the vehicle group and increased for approximately 24 hours in the high dose of UA group, which also had lower levels of malondialdehyde at day 5. Mortality (12.5%), symptomatic central nervous system bleeding (0%), and outcome at day 90 were similar in the 3 treatment arms; one patient in the high-dose group had a mild gouty episode.

Conclusions—

The administration of UA appears to be safe, decreases lipid peroxidation, and prevents an early fall of UA in serum in patients treated with rt-PA within 3 hours of stroke onset. The clinical efficacy of dual administration of exogenous UA and rt-PA deserves further investigation in a larger acute stroke trial.
Early Arterial Study in the Prediction of Mortality After Acute Ischemic Stroke
Authors: Ois Angel , Cuadrado-Godia Elisa , Jiménez-Conde Jordi , Gomis Meritxell , Rodríguez-Campello Ana , Martínez-Rodríguez Jose E. , Munteis Elvira , Roquer Jaume
Published: May 2007

Background and Purpose—

The purpose of this study was to evaluate the value of the initial arterial study as a predictor of 90-day mortality in patients with acute ischemic stroke.

Methods—

A total of 1220 unselected patients assessed during the first 24 hours after stroke onset were prospectively studied. Initial stroke severity was evaluated by the National Institutes of Health Stroke Scale and dichotomized in mild (National Institutes of Health Stroke Scale ≤7) and severe (National Institutes of Health Stroke Scale >7). Severe arterial stenosis (≥70%) or arterial occlusion in the symptomatic territory was determined by a Doppler study and also by additional explorations (carotid duplex, MR or CT angiography) in the first 24 hours after admission. The following variables were also analyzed: age, gender, previous functional status, smoking, hypertension, hyperlipidemia, diabetes mellitus, peripheral arterial disease, ischemic heart disease, heart failure, atrial fibrillation, previous stroke, and prior use of antithrombotic or statins. Ninety-day mortality was the end point of the study.

Results—

Ninety-day mortality was 15.7%. A total of 25.5% of all deaths were in patients with mild stroke. In addition to well-known factors related to mortality (age, stroke severity, ischemic heart disease, heart failure, and previous disability), severe arterial stenosis/occlusion was the factor with the highest relationship with 90-day mortality (adjusted OR: stenosis 2.13, occlusion 4.42, both 3.36). Arterial stenosis/occlusion was a higher predictor of 90-day mortality in patients with mild (adjusted OR: 5.38) than severe stroke (adjusted OR: 3.05).

Conclusions—

Severe arterial stenosis/occlusion in the early arterial study was highly related with 90-day mortality in an unselected series of patients with stroke. These data achieve special relevance in patients with initial mild stroke.
Recent Changes in the Pacific Subtropical Cells Inferred from an Eddy-Resolving Ocean Circulation Model*
Authors: Cheng Wei , McPhaden Michael J. , Zhang Dongxiao , Metzger E. Joseph
Published: May 2007

In this study the subtropical cells (STC) in the Pacific Ocean are analyzed using an eddy-resolving ocean general circulation model driven by atmospheric forcing for the years 1992–2003. In particular, the authors seek to identify decadal changes in the STCs in the model and to compare them with observations in order to understand the consequences of such changes for the equatorial ocean heat and mass budgets. The simulation shows a trend toward increasing pycnocline volume transport at 9°N and 9°S across the basin from 1992 to 2003. This increase [4.9 ± 1.0 Sv (Sv ≡ 106 m3 s−1)] is in qualitative agreement with observations and is attributed primarily to changes in the interior ocean transport, which are partially compensated by opposing western boundary transports. The subtropical meridional volume transport convergence anomalies in the model pycnocline are found to be consistent with anomalous volume transports in both the observed and modeled Equatorial Undercurrent, as well as with the magnitude of simulated anomalous upwelling transport at the base of the mixed layer in the eastern Pacific. As a result of the increased circulation intensity, heat transport divergence through the lateral boundaries of the tropical control volume (defined as the region between 9°N and 9°S, and from the surface to σθ = 25.3 isopycnal) increases, leading to a cooling of the tropical upper ocean despite the fact that net surface heat flux into the control volume has increased in the same time. As such, these results suggest that wind-driven changes in ocean transports associated with the subtropical cells play a central role in regulating tropical Pacific climate variability on decadal time scales.
Rossby Wave Instability and Apparent Phase Speeds in Large Ocean Basins
Authors: Isachsen P. E. , LaCasce J. H. , Pedlosky J.
Published: May 2007

The stability of baroclinic Rossby waves in large ocean basins is examined, and the quasigeostrophic (QG) results of LaCasce and Pedlosky are generalized. First, stability equations are derived for perturbations on large-scale waves, using the two-layer shallow-water system. These equations resemble the QG stability equations, except that they retain the variation of the internal deformation radius with latitude. The equations are solved numerically for different initial conditions through eigenmode calculations and time stepping. The fastest-growing eigenmodes are intensified at high latitudes, and the slower-growing modes are intensified at lower latitudes. All of the modes have meridional scales and growth times that are comparable to the deformation radius in the latitude range where the eigenmode is intensified. This is what one would expect if one had applied QG theory in latitude bands. The evolution of large-scale waves was then simulated using the Regional Ocean Modeling System primitive equation model. The results are consistent with the theoretical predictions, with deformation-scale perturbations growing at rates inversely proportional to the local deformation radius. The waves succumb to the perturbations at the mid- to high latitudes, but are able to cross the basin at low latitudes before doing so. Also, the barotropic waves produced by the instability propagate faster than the baroclinic long-wave speed, which may explain the discrepancy in speeds noted by Chelton and Schlax.
Multiple Jets of the Antarctic Circumpolar Current South of Australia*
Authors: Sokolov Serguei , Rintoul Stephen R.
Published: May 2007

Maps of the gradient of sea surface height (SSH) and sea surface temperature (SST) reveal that the Antarctic Circumpolar Current (ACC) consists of multiple jets or frontal filaments. The braided and patchy nature of the gradient fields seems at odds with the traditional view, derived from hydrographic sections, that the ACC is made up of three continuous circumpolar fronts. By applying a nonlinear fitting procedure to 638 weekly maps of SSH gradient (∇SSH), it is shown that the distribution of maxima in ∇SSH (i.e., fronts) is strongly peaked at particular values of absolute SSH (i.e., streamlines). The association between the jets and particular streamlines persists despite strong topographic and eddy–mean flow interactions, which cause the jets to merge, diverge, and fluctuate in intensity along their path. The SSH values corresponding to each frontal branch are nearly constant over the sector of the Southern Ocean between 100°E and 180°. The front positions inferred from SSH agree closely with positions inferred from hydrographic sections using traditional water mass criteria. Recognition of the multiple branches of the Southern Ocean fronts helps to reconcile differences between front locations determined by previous studies. Weekly maps of SSH are used to characterize the structure and variability of the ACC fronts and filaments. The path, width, and intensity of the frontal branches are influenced strongly by the bathymetry. The “meander envelopes” of the fronts are narrow on the northern slope of topographic ridges, where the sloping topography reinforces the β effect, and broader over abyssal plains.
Review Essay: Reconstructing Epistemology
Authors: Sassower Raphael
Published: May 2007

Though postmodernists, like Barbara Herrnstein Smith, seem to hold onto some epistemological and perhaps even metaphysical divide between the rationalists and all others (sometimes referred to as irrationalists), there is much more to gain when considering the overlapping similarities and common origins of different traditions or outlooks. In this way, a critical dialogue is more probable and could lead to more fruitful results.
A Novel Multidomain Computerized Cognitive Assessment for Attention-Deficit Hyperactivity Disorder: Evidence for Widespread and Circumscribed Cognitive Deficits
Authors: Leitner Yael , Doniger Glen M. , Barak Ran , Simon Ely S. , Hausdorff Jeffrey M.
Published: May 2007

Multidomain assessment may enhance the diagnosis of cognitive impairment in children with attention-deficit hyperactivity disorder (ADHD). A set of novel Web-enabled computerized tests has recently been shown to be valid for identifying mild cognitive impairment and characterizing the cognitive profile associated with various disorders. It was anticipated that these tests would be well suited for use in children with ADHD. The authors tested this idea in a pilot study of 15 children (12 males, 3 females; mean age, 11 years 10 months; range, 9-15 years) with ADHD and 15 age-, education-, and gender-matched controls. The profile of cognitive impairment in ADHD children off methylphenidate across 6 cognitive domains (memory, executive function, visual-spatial skills, verbal function, attention, and motor skills) was described relative to controls. The effect of treatment with methylphenidate was examined by comparing the ADHD children on methylphenidate and on placebo (administered in a double-blind randomized fashion) relative to controls and by comparing the ADHD children on methylphenidate relative to placebo. Significant impairment in ADHD was evident in memory, visual-spatial, verbal, and attention domains, and near-significant impairment was observed in executive function and motor skills. On methylphenidate but not placebo, performance was comparable to controls in immediate verbal memory, psychomotor accuracy, visual-spatial, verbal rhyming, and overall battery performance. Significant improvement with administration of methylphenidate relative to placebo was evident for psychomotor accuracy, verbal rhyming, and overall battery performance. Hence, on the limited basis of this pilot study, the set of computerized tests studied appears to be useful for measuring cognitive function in ADHD; however, additional studies are needed to confirm this.
Abnormalities of Tactile Sensory Function in Children With Dystonic and Diplegic Cerebral Palsy
Authors: Sanger Terence D. , Kukke Sahana N.
Published: May 2007

Recent studies have shown the presence of sensory dysfunction in adults with focal dystonias. The authors hypothesize that children with secondary dystonia due to cerebral palsy may share a similar sensory dysfunction. To test this hypothesis, they evaluated tactile spatial discrimination threshold using Johnson, Van Boven, Phillips domes in 10 children with cerebral palsy and upper extremity dystonia, 8 children with diplegic cerebral palsy without involvement of the arms, and 21 unaffected children. Both patient groups had poor tactile discrimination compared with controls. The authors therefore conclude that children with secondary dystonia and diplegia due to cerebral palsy have deficits of tactile sensation that are similar to deficits seen in adults with focal dystonia. These results are the first to test the spatial discrimination threshold using Johnson, Van Boven, Phillips domes in children with cerebral palsy.
Necrotic Skin Lesions and Cerebral Infarction in the Newborn: Two Case Reports
Authors: Bednarek Nathalie , Morville Patrice , Delebarre Glwadys , Akhavi Ahmad , Sommer Christelle
Published: May 2007

Localized skin necrosis with deeper soft tissue injury at birth is unusual and has been rarely reported in association with cerebral infarction. Two cases with forearm necrotic skin associated with injured deeper soft tissue are described in which brachial artery thrombosis was documented. Considering the possibility of disseminated thrombosis, cerebral ultrasound showed brain infarction due to unilateral middle cerebral artery thrombosis on Doppler. The origin of the embolism was identified in the inferior vena cava and umbilical and portal vein. No thrombophilia or other risk factors were identified. The various causes of the cutaneous lesions pointed to an antenatal process whose etiology and mechanisms are discussed. Localized necrotic skin lesions must be considered as part of a systemic embolic process and can lead to extensive especially cerebral ultrasound exploration.
The Correlation of Seizure Characteristics and Hippocampal Volumetric Magnetic Resonance Imaging Findings in Children With Idiopathic Partial Epilepsy
Authors: Eroğlu Burçin , Kurul Semra , Çakmakçi Handan , Dirik Eray
Published: May 2007

Cerebral volumetric measurements based on magnetic resonance imaging have been established as advanced morphometric techniques with anatomic and clinical utility in adults and children with epilepsy. This study investigated the cerebral and hippocampal volumes in children with idiopathic partial epilepsy to detect the factors correlated with volume reduction. Magnetic resonance imaging volumetric measurements were performed of the total cerebral and hippocampal formation volumes in 30 patients with idiopathic partial epilepsy between 3 to 18 years old. The cerebral and the total, right, and left hippocampal volumes of the study and control patients were detected using volumetric magnetic resonance imaging, and the volumes were compared between the 2 groups. In study patients, the correlation between volumetric findings and seizure characteristics was evaluated. The results suggested that children with idiopathic partial epilepsy had significant hippocampal volume reduction that was not influenced by the age of onset and the duration of epilepsy.
Governance for Broadened Accountability: Blending Deliberate and Emergent Strategizing
Authors: Morrison J. Bart , Salipante Paul
Published: May 2007

The nonprofit sector is challenged by increasing public and stakeholder demands for a broadened accountability. Strong expectations for performance accountability now accompany those for fiscal accountability. In response, better concepts of nonprofit accountability are being developed in the literature. However, knowledge of governance practices that can achieve broadened accountability has lagged. This article attempts to stimulate research and contribute to such knowledge by (a) synthesizing concepts of accountability presented by Behn (2001), Kearns (1996), and Boland and Schultze (1996) into two categories: rule-based and negotiable accountability; (b) developing grounded concepts concerning the practice of governance by nonprofit leaders; and (c) exploring the interrelationships of the previously discrete concepts of deliberate strategy, emergent strategy, and accountability. The study's ethnographic methods recorded and analyzed real-life interactions involving a board chair—chief executive officer pair. The article presents a detailed narrative description of these actions to convey its key concept, blended strategizing, and to provide stimulus for new practice by leaders in governance situations.
Electro-Mechanical Impedance-Based Wireless Structural Health Monitoring Using PCA-Data Compression and k-means Clustering Algorithms
Authors: Park Seunghee , Lee Jong-Jae , Yun Chung-Bang , Inman Daniel J.
Published: May 2007

This article presents a practical method for an electro-mechanical impedance-based wireless structural health monitoring (SHM), which incorporates the principal component analysis (PCA)-based data compression and k-means clustering-based pattern recognition. An on-board active sensor system, which consists of a miniaturized impedance measuring chip (AD5933) and a self-sensing macro-fiber composite (MFC) patch, is utilized as a next-generation toolkit of the electromechanical impedance-based SHM system. The PCA algorithm is applied to the raw impedance data obtained from the MFC patch to enhance a local data analysis-capability of the on-board active sensor system, maintaining the essential vibration characteristics and eliminating the unwanted noises through the data compression. Then, the root-mean square-deviation (RMSD)-based damage detection result using the PCA-compressed impedances is compared with the result obtained from the raw impedance data without the PCA preprocessing. Furthermore, the k-means clustering-based unsupervised pattern recognition, employing only two principal components, is implemented. The effectiveness of the proposed methods for a practical use of the electromechanical impedance-based wireless SHM is verified through an experimental study consisting of inspecting loose bolts in a bolt-jointed aluminum structure.
Continuum Approach to Damage Mechanics of Composite Materials with Fabric Tensors
Authors: Voyiadjis George Z. , Kattan Peter I. , Taqieddin Ziad N.
Published: May 2007

The major objective of this work is to apply continuum damage mechanics introduced through the concept of fabric tensors to composite materials within the framework of elasticity theory. A model of directional data damage mechanics for composite materials is formulated using fabric tensors. The physical meaning of damage is enhanced and understood better through the introduction of fabric tensors into the analysis of damage of composite materials. The `continuum approach' is used here to link the fabric tensors' damage effect to the behavior of composite materials. In this approach, damage with fabric tensors is introduced to the composite medium, where the latter is treated as a homogenized material. Also, the overall properties of the composite system as a whole are used without using the constituent properties.

A generalized formulation of damage evolution is derived in a mathematically consistent manner that is based on sound thermodynamic principles. A numerical example is presented to show the applicability. In addition, damage evolution for the one-dimensional tension case is also illustrated.
Iliac Conduit for Deploying Aortic Endografts: An All-Autogenous Option
Authors: Eidt John F. , Ali Ahsan T.
Published: May 2007

Unfavorable iliac anatomy, such as small caliber or circumferential calcification, can cause problems during delivery of aortic endografts and lead to potential complications. An iliac artery conduit “chimney” has been used to deliver the large caliber endoprosthesis using a Dacron graft sewn onto the iliac bifurcation. An all-autogenous revascularization option allows for hypogastric bypass while limiting the use of synthetic graft.
Heat shock protein inhibition is associated with activation of the unfolded protein response pathway in myeloma plasma cells
Authors: Davenport Emma L. , Moore Hannah E. , Dunlop Alan S. , Sharp Swee Y. , Workman Paul , Morgan Gareth J. , Davies Faith E.
Published: May 2007

Plasma cells producing high levels of paraprotein are dependent on the unfolded protein response (UPR) and chaperone proteins to ensure correct protein folding and cell survival. We hypothesized that disrupting client–chaperone interactions using heat shock protein 90 (Hsp90) inhibitors would result in an inability to handle immunoglobulin production with the induction of the UPR and myeloma cell death. To study this, myeloma cells were treated with Hsp90 inhibitors as well as known endoplasmic reticulum stress inducers and proteasome inhibitors. Treatment with thapsigargin and tunicamycin led to the activation of all 3 branches of the UPR, with early splicing of XBP1 indicative of IRE1 activation, upregulation of CHOP consistent with ER resident kinase (PERK) activation, and activating transcription factor 6 (ATF6) splicing. 17-AAG and radicicol also induced splicing of XBP1, with the induction of CHOP and activation of ATF6, whereas bortezomib resulted in the induction of CHOP and activation of ATF6 with minimal effects on XBP1. After treatment with all drugs, expression levels of the molecular chaperones BiP and GRP94 were increased. All drugs inhibited proliferation and induced cell death with activation of JNK and caspase cleavage. In conclusion, Hsp90 inhibitors induce myeloma cell death at least in part via endoplasmic reticulum stress and the UPR death pathway.
A hybrid multiscale Monte Carlo algorithm (HyMSMC) to cope with disparity in time scales and species populations in intracellular networks
Authors: Samant Asawari , Ogunnaike Babatunde A , Vlachos Dionisios G
Published: May 2007

Background

The fundamental role that intrinsic stochasticity plays in cellular functions has been shown via numerous computational and experimental studies. In the face of such evidence, it is important that intracellular networks are simulated with stochastic algorithms that can capture molecular fluctuations. However, separation of time scales and disparity in species population, two common features of intracellular networks, make stochastic simulation of such networks computationally prohibitive. While recent work has addressed each of these challenges separately, a generic algorithm that can simultaneously tackle disparity in time scales and population scales in stochastic systems is currently lacking. In this paper, we propose the hybrid, multiscale Monte Carlo (HyMSMC) method that fills in this void.

Results

The proposed HyMSMC method blends stochastic singular perturbation concepts, to deal with potential stiffness, with a hybrid of exact and coarse-grained stochastic algorithms, to cope with separation in population sizes. In addition, we introduce the computational singular perturbation (CSP) method as a means of systematically partitioning fast and slow networks and computing relaxation times for convergence. We also propose a new criteria of convergence of fast networks to stochastic low-dimensional manifolds, which further accelerates the algorithm.

Conclusion

We use several prototype and biological examples, including a gene expression model displaying bistability, to demonstrate the efficiency, accuracy and applicability of the HyMSMC method. Bistable models serve as stringent tests for the success of multiscale MC methods and illustrate limitations of some literature methods.
Ethics takes time, but not that long
Authors: Hansson Mats G , Kihlbom Ulrik , Tuvemo Torsten , Olsen Leif A , Rodriguez Alina
Published: May 2007

Background

Time and communication are important aspects of the medical consultation. Physician behavior in real-life pediatric consultations in relation to ethical practice, such as informed consent (provision of information, understanding), respect for integrity and patient autonomy (decision-making), has not been subjected to thorough empirical investigation. Such investigations are important tools in developing sound ethical praxis.

Methods

21 consultations for inguinal hernia were video recorded and observers independently assessed global impressions of provision of information, understanding, respect for integrity, and participation in decision making. The consultations were analyzed for the occurrence of specific physician verbal and nonverbal behaviors and length of time in minutes.

Results

All of the consultations took less than 20 minutes, the majority consisting of 10 minutes or less. Despite this narrow time frame, we found strong and consistent association between increasing time and higher ratings on all components of ethical practice: information, (β = .43), understanding (β = .52), respect for integrity (β = .60), and decision making (β = .43). Positive nonverbal behaviors by physicians during the consultation were associated particularly with respect for integrity (β =.36). Positive behaviors by physicians during the physical examination were related to respect for children's integrity.

Conclusion

Time was of essence for the ethical encounter. Further, verbal and nonverbal positive behaviors by the physicians also contributed to higher ratings of ethical aspects. These results can help to improve quality of ethical practice in pediatric settings and are of relevance for teaching and policy makers.
β-Arrestin-Dependent Parathyroid Hormone-Stimulated Extracellular Signal-Regulated Kinase Activation and Parathyroid Hormone Type 1 Receptor Internalization
Authors: Sneddon W. Bruce , Friedman Peter A.
Published: May 2007

PTH regulates renal calcium homeostasis by actions on the distal nephron. PTH-induced calcium transport in mouse distal convoluted tubule (DCT) cells requires activation of ERK1/2. ERK activation by β-adrenergic receptors occurs in a biphasic manner and involves receptor internalization. An early rapid phase is β-arrestin (βAr) independent, whereas prolonged activation is βAr dependent. We characterized PTH-stimulated ERK activation and the involvement of receptor internalization and βAr dependence. In DCT cells, PTH transiently activated ERK maximally at 5 min and then returned to baseline. βAr dependence of PTH receptor (PTH1R)-mediated ERK stimulation was assessed using mouse embryonic fibroblasts (MEFs) from βAr1- and -2-null mice. In wild-type MEFs, PTH(1–34)-stimulated ERK activation peaked after 5 min, was 50% maximal after 15 min, and then recovered to 80% of maximal stimulation by 30 min. In MEFs null for βAr1 and -2, PTH-stimulated ERK activation peaked by 5 min and returned to baseline. The effect was identical in βAr2-null MEFs. In βAr1-null MEFs, ERK exhibited delayed activation and remained elevated. PTH-stimulated ERK activation and receptor endocytosis were not inhibited by the clathrin-binding domain of βAr1 [Ar(319–418)]. Coexpression of the sodium proton exchanger regulatory factor 1 (NHERF1) with Ar(319–418) blocked PTH1R internalization. We conclude that PTH-stimulated ERK activation in DCT cells proceeds with a rapid but transient phase that may involve βAr1. Furthermore, the βAr-dependent late phase of ERK activation by PTH requires the participation of βAr2 and PTH1R internalization.
Early Pregnancy Maternal Endocrine Insulin-Like Growth Factor I Programs the Placenta for Increased Functional Capacity throughout Gestation
Authors: Sferruzzi-Perri Amanda N. , Owens Julie A. , Standen Prue , Taylor Robyn L. , Robinson Jeffrey S. , Roberts Claire T.
Published: May 2007

In early pregnancy, the concentrations of IGFs increase in maternal blood. Treatment of pregnant guinea pigs with IGFs in early to midpregnancy enhances placental glucose transport and fetal growth and viability near term. In the current study, we determined whether exogenous IGFs altered placental gene expression, transport, and nutrient partitioning during treatment, which may then persist. Guinea pigs were infused with IGF-I, IGF-II (both 1 mg/kg·d) or vehicle sc from d 20–35 of pregnancy and killed on d 35 (term is 70 d) after administration of [3H]methyl-d-glucose (MG) and [14C]amino-isobutyric acid (AIB). IGF-I increased placental and fetal weights (+15 and +17%, respectively) and MG and AIB uptake by the placenta (+42 and +68%, respectively) and fetus (+59 and +90%, respectively). IGF-I increased placental mRNA expression of the amino acid transporter gene Slc38a2 (+780%) and reduced that of Igf2 (−51%), without altering the glucose transporter Slc2a1 or Vegf and Igf1 genes. There were modest effects of IGF-I treatment on MG and AIB uptake by individual maternal tissues and no effect on plasma glucose, total amino acids, free fatty acids, triglycerides, and cholesterol concentrations. IGF-II treatment of the mother did not alter any maternal, fetal or placental parameter. In conclusion, exogenous IGF-I, but not IGF-II, in early pregnancy increases placental transport of MG and AIB, enhancing midgestational fetal nutrient uptake and growth. This suggests that early pregnancy rises in maternal circulating IGF-I play a major role in regulating placental growth and functional development and thus fetal growth throughout gestation.
Tolerance modelling and robust design for concurrent engineering
Authors: Hu J , Peng Y
Published: May 2007

This article presents a tolerance modelling and robust design approach to support concurrent engineering. This method allows the designer to synthetically specify dimensional and geometric tolerance, considering assembly functional requirements (AFRs) and manufacturing costs. First, features of ISO/TC 213 are used as the basis for the construction of tolerance network and tolerance model for assembly. Second, the manufacturing cost-tolerance model for cylindrical and planar features is established. This model addresses not only dimensional tolerances but also geometric tolerances and nominal parameters. Finally, the robust tolerance optimization model is established, and genetic arithmetic is used to obtain robust tolerance values. The proposed approach is consistent with the philosophy of concurrent engineering, in which AFRs are satisfied and manufacturing cost is reduced. A design instance is introduced to show the validity of this method.
Micropower generation with microgasturbines: A challenge
Authors: Peirs J , Waumans T , Vleugels P , Al-Bender F , Stevens T , Verstraete T , Stevens S , D'hulst R , Verstraete D , Fiorini P , Van den Braembussche R , Driesen J , Puers R , Hendrick P , Baelmans M , Reynaerts D
Published: May 2007

This paper describes the development of a microgasturbine with a rotor diameter of 20 mm. The target electrical power output lies around 1 kW. The total system fits in a cylinder with a diameter of 95 mm and a length of 120 mm. The system contains the same components as a large gasturbine generator: compressor, recuperator, combustion chamber, turbine, and electrical generator.

Major challenges are the high rotational speed (500 000 r/min), high turbine inlet temperature (1200 K), and the efficiency of the components. Because of the small dimensions, the flow through compressor and turbine is characterized by relatively low Reynolds numbers. The higher flow losses and inherently lower efficiency require a higher blade tip speed (524 m/s) than for large turbines (300-400 m/s).

To minimize wear and frictional losses, the rotor is mounted on aerodynamic bearings. To withstand the high centrifugal stresses, a high-strength steel is used for compressor and shaft. The turbine is made of a Si3N4-TiN ceramic composite to withstand the combination of elevated stress and temperature.
A Technique for Excision of Abdominal and Pelvic Neuroblastomas
Authors: Kiely Edward
Published: May 2007

INTRODUCTION

As neuroblastomas usually envelope major vessels, excision poses a significant technical problem.

PATIENTS AND METHODS

Over a 22-year period, 234 infants and children have undergone attempted surgical excision of abdominal or pelvic neuroblastomas using a consistent surgical approach. This entails a systematic dissection of the involved vessels prior to removal of the tumour.

RESULTS

Macroscopically complete or near complete tumour clearance was achieved in 89% of cases. Three aortic injuries occurred which required repair.

CONCLUSION

The described technique is safe and reproducible and allows tumour clearance in the majority offfected children.
Mutual Mentoring in Laparoscopic Urology – A Natural Progression from Laparoscopic Fellowship
Authors: Jones A , Eden C , Sullivan ME
Published: May 2007

INTRODUCTION

The objective of this study is to report a novel system of ‘mutual mentoring’ that overcomes the limited availability of laparoscopic mentors and allows progression from laboratory and fellowship experience into independent clinical practice.

PATIENTS AND METHODS

A total of 88 laparoscopic cases were performed during the fellowship. In the first 2 years as consultants, we (AJ and MS) performed 151 cases with mutual mentoring (simple nephrectomy [n = 28], radical nephrectomy [n = 35], nephro-ureterectomy [n = 19], pyeloplasty [n = 31], pelvic LND [n = 21], others [n = 17]).

RESULTS

Mutual mentoring has resulted in the successful introduction of laparoscopic services to two hospitals, allowing an exposure to an average of two cases a week. Complication rates are acceptable and objective measures such as conversion rates, operative time and blood loss appear to be improving.

CONCLUSIONS

Mutual mentoring allows for a greater through-put of cases, a high level of assistance, advice with intra-operative decisions and the potential to ‘share’ cases, reducing fatigue and increasing experience. It provides significant moral support in the difficult early days of starting the service. Its disadvantages are that it is time consuming and is geographically restrictive. Mutual mentoring has allowed us to introduce a laparoscopic service at our respective hospitals with high case-load acceptable complication rates.
The Impact of Patient-Controlled Analgesia on Laparoscopic Cholecystectomy
Authors: Sinha S , Munikrishnan V , Montgomery J , Mitchell SJ
Published: May 2007

INTRODUCTION

Laparoscopic cholecystectomy has revolutionised the management of symptomatic gallstones and is increasingly performed as a day-case procedure. The aim of this study was to assess the impact of opioid patient-controlled analgesia (PCA) on elective laparoscopic cholecystectomy.

PATIENTS AND METHODS

In a prospective, non-randomised, observational study, 76 consecutive patients who underwent elective in-patient laparoscopic cholecystectomy were reviewed. Six patients with complicated gall stone disease and four patients who converted from laparoscopic to an open operation were excluded.

RESULTS

Of the 66 remaining in the study group, 25 patients received morphine-PCA and, of these, 9 were fit for discharge. In contrast, 41 patients did not receive PCA and, of these, 27 were fit for discharge (P < 0.05). Median Aldrete score in the PCA group was 16 and in the non-PCA group 18 (P < 0.05). Postoperative nausea and vomiting were more common in patients receiving a morphine-based PCA and with in those with higher anti-emetic requirement (10/25 in PCA and 7/41 non-PCA groups; P < 0.05).

CONCLUSIONS

Routine postoperative opioid PCA prolongs the recovery and in-patient stay following elective laparoscopic cholecystectomy. Its role in postoperative pain management in routine laparoscopic cholecystectomy should be questioned.
Out-Patient Flexible Cystoscopy Using a Disposable Slide-On™ Endosheath System
Authors: Kimuli Michael , Lloyd Stuart N
Published: May 2007

INTRODUCTION

The aim of this study was to investigate the feasibility of out-patient flexible cystoscopy.

PATIENTS AND METHODS

Twenty-seven patients awaiting diagnostic or check cystoscopy in Leeds, UK were invited to undergo out-patient flexible cystoscopy using a CST-2000 Flexible Cystoscope (Vision Sciences; Natick, MA, USA) using the sterile single-use slide-on™ disposable endosheath endoscope system (EndoSheath®; Vision Sciences). The performance of the cystoscope was evaluated, and the patients' experiences were documented using a questionnaire.

RESULTS

The out-patient setting proved to be ideal for flexible cystoscopy. The cystoscope was rated highly for image quality, ease of use and handling. All patients complimented us on the service and preferred out-patients to a day-ward or theatre attendance.

CONCLUSIONS

This study demonstrates that it is possible to perform out-patient flexible cystoscopy safely, economically and efficiently with the aid of a disposable endoscope system.
Ecstasy-Associated Pneumomediastinum
Authors: Marasco Silvana F , Lim H Kiat
Published: May 2007

INTRODUCTION

Ecstasy, also known as MDMA (3,4, methylenedioxymethamphetamine), is a popular illicit party drug amongst young adults. The drug induces a state of euphoria secondary to its stimulant activity in the central nervous system.

PATIENTS AND METHODS

A database review at two major inner city hospitals was undertaken to identify patients presenting with pneumomediastinum and their charts reviewed. A Medline review of all reported cases of pneumomediastinum associated with ecstasy abuse was undertaken.

RESULTS

A total of 56 patients presenting with pneumomediastinum were identified over a 5-year period. Review of the charts revealed a history of ecstasy use in the hours prior to presentation in six of these patients, representing the largest series reported to date.

CONCLUSIONS

Review of previously reported cases reveals the likely mechanism is due to Valsalva manoeuvre during periods of extreme physical exertion, and not a direct pharmacological effect of the drug.
A Comparison of the Views of Patients and Medical Staff in Relation to the Process of Informed Consent
Authors: Berry MG , Unwin Jennifer , Ross GL , Peacock Elizabeth , Juma A
Published: May 2007

INTRODUCTION

The quality and quantity of information required in the consent process is well documented, but there is little extant literature regarding timing of either information about the proposed procedure or the act of consent itself. With the recent introduction of a new NHS-wide consent form, we wished to determine the preferences of both patients and staff to ascertain whether any concordance of views existed.

PATIENTS AND METHODS

A 10-point questionnaire, developed in conjunction with the department of clinical psychology was completed by 242 patients selected for surgery over a 4-month period. Identical questionnaires were completed by local staff (n = 50) and national consultant plastic surgeons (n = 56).

RESULTS

The cumulative majority (61.8%) preferred information at the specialist out-patient appointment (OPA). There was a significant difference (P < 0.001) between patients and staff as to information provision by the specialist as compared to non-specialists; staff indicating it much more strongly. As to the timing of consent form signature, 40.2% preferred signature on admission with no statistically significant difference between subgroups. An additional pre-operative clinic, for consent form signing, was selected by 27.3%. Staff expressed this view more often than patients (P < 0.001).

CONCLUSIONS

Patients prefer information about a planned surgical procedure at their specialist OPA and final consent for surgery when admitted to the ward. Staff had quite definite views and felt an additional pre-operative out-patient appointment to be beneficial, more so than the patients themselves.
Avulsion Injuries of the Hamstring Origin – A Series of 12 Patients and Management Algorithm
Authors: Gidwani Sam , Bircher Martin D
Published: May 2007

INTRODUCTION

Injuries to the origin of the hamstring muscles usually occur in athletes and can result in an avulsion fracture of the ischium, an avulsion of the ischial apophysis, or a pure avulsion of the hamstring tendons themselves, depending on the patient' sage. These are rare injuries in the general population and are often initially misdiagnosed as a simple ‘hamstring pull’, leading to the development of chronic pain and disability.

PATIENTS AND METHODS

We present a retrospective case series of the 12 patients with such injuies who presented or were referred consecutively to the senior author between 1997 and 2006.

RESULTS

There was a significant delay (5 months to 12 years) in the diagnosis of the injury in 8 of the 12 patients. Five of these 8 patients required more extensive surgery than would otherwise have been required as a result of this delay, but all recovered well. The sporting career of one of the remaining three patients had already been brought to an end by her injury and the subsequent disability, and she elected not to have surgery. Of the four patients who were diagnosed acutely, three required surgery, and all four had an excellent result.

CONCLUSIONS

Injuries to the hamstring origin are rare and are often initially misdiagnosed as a simple ‘hamstring pull’, leading to the development of chronic pain and disability. Displaced injuries of the ischial apophysis and pure tendon avulsions are probably best treated surgically in the acute setting. As a result of our experience with these patients, we have produced a management algorithm.
Inter- and Intra-Observer Variation of the Schatzker and AO/OTA Classifications of Tibial Plateau Fractures and a Proposal of a New Classification System
Authors: Charalambous CP , Tryfonidis M , Alvi F , Moran M , Fang C , Samaraji R , Hirst P
Published: May 2007

INTRODUCTION

The aim of this study was to evaluate the intra- and inter-observer variation of the Schatzker and AO/OTA classifications in assessing tibial plateau fractures, using plain radiographs.

PATIENTS AND METHODS

Fifty tibial plateau fractures were classified independently by six observers as per the Schatzker and AO/OTA classifications, using antero-posterior and lateral plain radiographs. Assessment was done on two occasions, 8 weeks apart.

RESULTS

We found that both the Schatzker and AO/OTA classifications have a high intra-observer (κ = 0.57 and 0.53, respectively), and inter-observer (κ = 0.41 and 0.43, respectively) variation. Classification of tibial plateau fractures into unicondylar versus bicondylar and pure splits versus articular depression ± split conferred improved inter- and intra-observer variation.

CONCLUSIONS

The high inter-observer variation found for the Schatzker and AO/OTA classifications must be taken into consideration when these are used as a guidance of treatment and when used in evaluating patients' outcome. Simply classifying tibial plateau fractures into unicondylar versus bicondylar and pure splits versus articular depression ± split may be more reliable.
Touched by Suicide: Bridging The Perspectives of Survivors and Clinicians
Authors: Myers Michael F. , Fine Carla
Published: May 2007

This article is a revised version of an invited plenary address given at the 39th Annual Conference of the American Association of Suicidology. The authors, a psychiatrist and a writer survivor, outline and summarize the different ways in which professionals and survivors come to an understanding of suicide. They explain how each group often exists independently and separate from the other—by cognitive and emotional dissonance, by private language, by psychological defenses and miscommunication—and call for dialog. They argue that both perspectives are essential to advance the science of suicidology and to give hope and meaning to those bereaved by suicide.
Control‐Group Study of an Intervention Training Program for Youth Suicide Prevention
Authors: Chagnon François , Houle Janie , Marcoux Isabelle , Renaud Johanne
Published: May 2007

Few studies have examined whether training can improve competency in intervening with suicidal youths. In this study we attempted to verify the effectiveness of such a training program on helper competency. Forty‐three helpers who received the training were compared with 28 helpers who did not. Participants who received the training improved in knowledge, attitudes, and intervention skills following the training, compared with the control group across measures. Their gains were maintained at 6‐month follow‐up. In this sample, implementation of a one‐time training program improved helpers' competencies in youth suicide intervention.
Utah Youth Suicide Study: Barriers to Mental Health Treatment for Adolescents
Authors: Moskos Michelle A. , Olson Lenora , Halbern Sarah R. , Gray Doug
Published: May 2007

Forty‐nine suicide cases were drawn from an original sample of 151 consecutive youth suicide deaths. We used information from 270 interviews with parents and other survivors to evaluate mental health treatment sought for and by the decedent and barriers to mental health treatment. Participants reported the same primary barriers for the decedent: belief that nothing could help, seeking help is a sign of weakness or failure, reluctance to admit to having mental health problems, denial of problems, and too embarrassed to seek help. It is suggested that the stigma of mental illness is a considerable barrier to mental health treatment.
Multiple Pathways from Stress to Suicidality and the Protective Effect of Social Support in Hong Kong Adolescents
Authors: Cheng Sheung‐Tak , Chan Alfred C. M.
Published: May 2007

Two theoretical models were constructed to illustrate how stressful events, family and friends support, depression, substance use, and death attitude mutually influence to create cumulative risks for suicide. The models were evaluated using structural equation modeling. Results showed that suicidality was strongly predicted by death attitude, depression, and substance use which together form a dangerous combination of risk factors at the personal level. Within the adolescent's social environment, stressful events increased suicidality through intensifying depression, substance use, and death acceptance, whereas family and friends support lowered it, partly through reducing stress and death acceptance. The effect (direct and indirect combined) of family support was much stronger than that of friends support. Enhancing stress coping ability, promoting positive family relationships, and attacking attitudes supportive of death might be the best strategies to prevent youth suicide.