bluuebunny/crossref_metadata_2025 huggingface dataset:
Two-Level Signalized Intersection
Authors: Shin Eon Kyo , Lee Jang Hee , Kim Ju Hyun , Kim Jung Sik , Jeong Yong Woo
Published: November 2008

Severe traffic congestion often occurs at intersections of high-volume traffic arteries. To reduce this congestion, innovative intersection designs such as the single-point urban interchange (SPUI), center-turn overpass (CTO), and echelon interchange (EI) have been implemented. This paper introduces a new type of intersection, the two-level signalized intersection (TLSI), which improves the efficiency of intersection operations under a wide variety of traffic conditions. The paper compares the TLSI with other innovative intersection types. Unlike the SPUI, CTO, or EI, the TLSI provides for complete separation of east–west and north–south traffic. The TLSI also enables the use of directional separation and leading, lagging, or overlapping lefts on both upper and lower levels. Simulation results indicate that, compared with these other innovative intersection types, the TLSI has the shortest delay times in most evaluation scenarios as well as the least sensitivity to variations in traffic volume. However, the TLSI shows significant delay when traffic volumes on the major and minor roads are vastly different.
Safety Grates for Cross-Drainage Culverts
Authors: Sicking Dean L. , Bielenberg Robert W. , Rohde John R. , Reid John D. , Faller Ronald K. , Polivka Karla A.
Published: November 2008

This paper presents findings of an investigation of the safety performance of culvert safety grates when installed on slopes as steep as 3:1, as recommended by the AASHTO Roadside Design Guide (RDG). LS-DYNA modeling was used to identify critical impact conditions for roadside culvert grates installed on 3:1 slopes. Two full-scale vehicle crash tests were conducted under the guidelines of NCHRP Report 350 on a 6.4- × 6.4-m (21-×21-ft) culvert safety grate installed on a 3:1 slope. The full-scale crash tests demonstrated that the AASHTO RDG recommended safety grates provide acceptable safety performance when installed on 3:1 slopes.
Culvert Hydraulics
Authors: Hotchkiss Rollin H. , Thiele Elizabeth A. , Nelson E. James , Thompson Philip L.
Published: November 2008

Several computer programs are available to analyze culvert hydraulics, including HY-8, FishXing, Broken-back Culvert Analysis Program (BCAP), Hydraflow Express, CulvertMaster, Culvert, and Hydrologic Engineering Center River Analysis System (HEC-RAS). The use of slightly different methodologies to complete the analysis results in different estimates for headwater depth, flow control, and outlet velocity. This paper compares the available hydraulic features and tests the accuracy of these seven programs as part of an effort to update the HY-8 program. Four test cases were developed. The flow controls, headwater depths, and outlet velocities were compared with values obtained through calculations based on best practice as outlined in the FHWA publication, Hydraulic Design Series No. 5. Several limitations were identified. BCAP has limited ability to analyze straight barrel culverts operating under outlet control with high tailwater, CulvertMaster reports outlet control for some low discharges as a surrogate for what is referred to as “entrance control,” Culvert misidentifies the location of hydraulic control for lower discharges and overestimates headwater elevations, and HydraFlow Express incorrectly uses critical depth at the outlet for inlet control calculations. With the test cases used here, HY-8, HEC-RAS, and FishXing most consistently agreed with accepted empirical results. It is recommended that program providers improve their products to replicate better the hydraulic conditions simulated in this paper and to extend program capabilities to include more environmentally sensitive design considerations such as fish passage.
Development of a Tool for Utility Conflict Data Management in the Project Development Process
Authors: Kraus Edgar , Quiroga Cesar , Le Jerry
Published: November 2008

A critical process for the timely development and delivery of highway construction projects is the early identification and depiction of utility interests that may interfere with proposed highway facilities. The effective management of such utility interests or conflicts involves utility adjustment (or design changes), inspection, and documentation. The large number of stakeholders and the magnitude of the process result in enormous amounts of data. Despite substantial data exchange among utility accommodation stakeholders, few standards exist for exchange and management of utility data in the project development process. With sample data provided by the Texas Department of Transportation, research described in this paper addresses the issue of utility conflict management by analyzing specific utility conflict data flows and data needs of stakeholders. The paper presents the product of this analysis, which is a prototype system for managing utility conflict data called the Utility Accommodation and Conflict Tracker.
Nonparametric Bayesian Estimation of Freeway Capacity Distribution from Censored Observations
Authors: Ozguven Eren Erman , Ozbay Kaan
Published: November 2008

Previous studies have been made of the usefulness and effectiveness of survival analysis in transportation and traffic engineering studies with incomplete data in which the Kaplan–Meier estimate is proposed for determining traffic capacity distribution. However, well-known estimators like Kaplan–Meier and Nelson–Aalen have several disadvantages that make it difficult to obtain the traffic capacity distribution. First, neither estimator is defined for all values of traffic flows possible. That is, the maximum flow followed by a breakdown defines the final point of the estimated distribution curve. Therefore, parametric fitting tools have to be applied to obtain the remaining portion of the curve. Moreover, the discontinuity and nonsmoothness of the Kaplan–Meier and Nelson–Aalen estimates make it difficult to ensure the robustness of the estimation. In this paper the Kaplan–Meier and Nelson–Aalen nonparametric estimators are used to obtain the traffic capacity function of four freeway sections. Then a Bayesian nonparametric estimator, which is shown to be a Bayesian extension of the Kaplan–Meier estimator, is introduced for estimating the capacity distribution. This estimator assumes a Dirichlet process prior for the survival function under the minimization of a squared-error loss function. The results indicate that the curves obtained by using the Bayesian estimation method are smoother than those obtained with the other estimator. This smoothness also ensures the continuity in the vicinity of censored observations. Furthermore, the Bayesian estimates can be obtained for any traffic flow value regardless of the availability of data only for certain ranges of observations (including censored data).
Crash Frequency Analysis with Generalized Additive Models
Authors: Xie Yuanchang , Zhang Yunlong
Published: November 2008

Recent crash frequency studies have been based primarily on generalized linear models, in which a linear relationship is usually assumed between the logarithm of expected crash frequency and other explanatory variables. For some explanatory variables, such a linear assumption may be invalid. It is therefore worthwhile to investigate other forms of relationships. This paper introduces generalized additive models to model crash frequency. Generalized additive models use smooth functions of each explanatory variable and are very flexible in modeling nonlinear relationships. On the basis of an intersection crash frequency data set collected in Toronto, Canada, a negative binomial generalized additive model is compared with two negative binomial generalized linear models. The comparison results show that the negative binomial generalized additive model performs best for both the Akaike information criterion and the fitting and predicting performance.
Analysis of Road Crash Frequency with Spatial Models
Authors: Aguero-Valverde Jonathan , Jovanis Paul P.
Published: November 2008

Despite the evident spatial character of road crashes, limited research has been conducted in road safety analysis to account for spatial correlation; further, the practical consequences of this omission are largely unknown. The purpose of this research is to explore the effect of spatial correlation in models of road crash frequency at the segment level. Different segment neighboring structures are tested to establish the most appropriate one in the context of modeling crash frequency in road networks. A full Bayes hierarchical approach is used with conditional autoregressive effects for the spatial correlation terms. Analysis of crash, traffic, and roadway inventory data from a rural county in Pennsylvania indicates the importance of including spatial correlation in road crash models. The models with spatial correlation show significantly better fit to the data than the Poisson lognormal model with only heterogeneity. Parameters significantly different from zero included annual average daily traffic (AADT) and shoulder widths less than 4 ft and between 6 and 10 ft. In four models with spatial correlation, goodness of fit was improved compared with the model including only heterogeneity. More important yet is the potential of spatial correlation to reduce the bias associated with model misspecification, as shown by the change in the estimate of the AADT coefficient and other parameters.
On the Entropy and Letter Frequencies of Powerfree Words
Authors: Grimm Uwe , Heuer Manuela
Published: November 2008

We review the recent progress in the investigation of powerfree words, with particular emphasis on binary cubefree and ternary squarefree words. Besides various bounds on the entropy, we provide bounds on letter frequencies and consider their empirical distribution obtained by an enumeration of binary cubefree words up to length 80.
Intracytoplasmic Cytokine Expression and T Cell Subset Distribution in the Peripheral Blood of Patients with Ankylosing Spondylitis
Authors: SZÁNTÓ SÁNDOR , ALEKSZA MAGDOLNA , MIHÁLY ERZSÉBET , LAKOS GABRIELLA , SZABÓ ZOLTÁN , VÉGVÁRI ANIKÓ , SIPKA SÁNDOR , SZEKANECZ ZOLTÁN
Published: November 2008

Objective

To determine the role of inflammatory mediators in the pathogenesis of ankylosing spondylitis (AS), we investigated peripheral blood lymphocyte subsets and their intracellular cytokine production.

Methods

The percentages of T and B lymphocytes, natural killer (NK) cells, activated T lymphocytes, CD4+ T helper (Th), and CD8+ T cytotoxic (Tc) cells were determined by flow cytometry in 42 patients with AS compared to 52 healthy controls. In order to assess circulating Th1/Th2 and Tc1/Tc2 subsets, we used a whole-blood cytometric assay based on the intracellular interferon-γ, interleukin 4 (IL-4), and IL-10 expression of the cells.

Results

In the peripheral blood, the frequencies of CD4+ T helper and CD56+ NK cells were higher in AS (54.8% and 16.2%, respectively) compared to controls (45.3% and 10.8%) (p < 0.05). The frequencies of Th0 (1.9% vs 0.8%) and Tc0 (2.1% vs 0.8%) cells were higher, while that of Tc1 cells was lower (26.6% vs 40.1%) in patients with AS versus controls (p < 0.05). The percentage of IL-10-producing Tc cells was significantly higher in AS (18.4%) versus controls (8.5%) (p < 0.05). Finally, the active phase of AS was associated with significantly lower percentage of IL-10-producing Tc cells in the peripheral blood (6.6%) compared to patients with inactive AS (23.1%).

Conclusion

Our results provide further evidence for an altered T cell subset distribution and intracytoplasmic cytokine balance in AS.
Systemic Lupus Erythematosus Features in Rheumatoid Arthritis and Their Effect on Overall Mortality
Authors: ICEN MURAT , NICOLA PAULO J. , MARADIT-KREMERS HILAL , CROWSON CYNTHIA S. , THERNEAU TERRY M. , MATTESON ERIC L. , GABRIEL SHERINE E.
Published: November 2008

Objective

Features of systemic lupus erythematosus (SLE) are commonly observed in patients with rheumatoid arthritis (RA). However, their frequency and clinical significance are uncertain. We examined the frequency of SLE features in RA and their effect on overall mortality.

Methods

We assembled a population-based incidence cohort of subjects aged ≥ 18 years first diagnosed with RA [1987 American College of Rheumatology (ACR) criteria] between 1955 and 1995. Information regarding disease characteristics, therapy, comorbidities, and SLE features (1982 ACR criteria) were collected from the complete inpatient and outpatient medical records. Cox regression models were used to estimate the mortality risk associated with lupus features.

Results

The study population comprised 603 subjects with incident RA (mean age 58 yrs, 73% women) with a mean followup time of 15 years. By 25 years after RA incidence, ≥ 4 SLE features were observed in 15.5% of the subjects with RA. After adjustment for age and sex, occurrence of ≥ 4 SLE features was associated with increased overall mortality [hazard ratio (HR) 5.54, 95% confidence interval (CI) 3.59–8.53].With further adjustment for RA characteristics, therapy, and comorbidities, the association weakened but remained statistically significant (HR 2.56, 95% CI 1.60–4.08). After adjustment for age, sex, RA characteristics, therapy, and comorbidities, thrombocytopenia (2.0, 95% CI 1.2, 3.1) and proteinuria (1.8, 95% CI 1.3, 2.6) were significantly associated with mortality.

Conclusion

SLE features were common in RA, given sufficient observation time. Subjects with RA who developed ≥ 4 SLE features had an increased risk of death. Proteinuria and thrombocytopenia were individually associated with an increased mortality risk.
Serum Autoantibodies and Their Clinical Associations in Patients with Childhood- and Adult-Onset Linear Scleroderma. A Single-Center Study
Authors: ARKACHAISRI THASCHAWEE , FERTIG NOREEN , PINO SALLY , MEDSGER THOMAS A.
Published: November 2008

Objective

To determine the frequency of selected serum autoantibodies and their clinical associations in patients with childhood-onset (ChO) or adult-onset (AO) linear scleroderma (LiScl) evaluated at a single institution.

Methods

Seventy-two patients (ChO = 40, AO = 32), including 12 with en coup de sabre, were studied. All ChO patients had disease onset before age 16 years. Clinical features (extent of cutaneous disease, activity, and joint contractures) were recorded. Antinuclear antibodies (ANA) were identified by indirect immunofluorescence (HEp-2 cells), and anti-single-stranded DNA (anti-ssDNA), antihistone (AHA), and antichromatin (AChA) autoantibodies were detected by ELISA.

Results

There were no significant differences between groups in regard to gender, proportion with LiScl/E, or clinical features except joint contractures (ChO > AO; p = 0.04). There were no differences in the frequency of ANA or other autoantibodies between the groups except for AHA (ChO > AO). AHA was more frequently found with anti-ssDNA (p < 0.0001). LiScl patients with positive anti-ssDNA and/or AHA had more extensive cutaneous involvement and more often had joint contractures (p < 0.05). Anti-ssDNAwas present more frequently inAO than in ChO patients with active lesions (p = 0.04). ANA and AChA were not associated with any clinical features. Both AHA and anti-ssDNA levels showed good correlation with disease severity.

Conclusion

Over two-thirds of LiScl patients had ANA. Patients with ChO were similar to those with AO with regard to the frequency of selected serum autoantibodies. Anti-ssDNA and AHA were frequently found together and both were associated with more extensive skin disease with joint contractures. LiScl disease severity correlated with the serum levels of both these antibodies.
Fibromyalgia, Systemic Lupus Erythematosus (SLE), and Evaluation of SLE Activity
Authors: WOLFE FREDERICK , PETRI MICHELLE , ALARCÓN GRACIELA S. , GOLDMAN JOHN , CHAKRAVARTY ELIZA F. , KATZ ROBERT S. , KARLSON ELIZABETH W.
Published: November 2008

Objective

To determine if fibromyalgia (FM) or fibromyalgia-ness (the tendency to respond to illness and psychosocial stress with fatigue, widespread pain, general increase in symptoms, and similar factors) is increased in patients with compared to those without systemic lupus erythematosus (SLE); to determine whether FM or fibromyalgia-ness biases the SLE Activity Questionnaire (SLAQ); and to determine if the SLAQ is overly sensitive to FM symptoms.

Methods

We developed a 16-item SLE Symptom Scale (SLESS) modeled on the SLAQ and used that scale to investigate the relation between SLE symptoms and fibromyalgia-ness in 23,321 patients with rheumatic disease. FM was diagnosed by survey FM criteria, and fibromyalgia-ness was measured using the Symptom Intensity (SI) Scale. As comparison groups, we combined patients with rheumatoid arthritis and noninflammatory rheumatic disorders into an “arthritis” group and also utilized a physician-diagnosed group of patients with FM.

Results

FM was identified in 22.1% of SLE and 17.0% of those with arthritis. The SI scale was minimally increased in SLE. The correlation between SLAQ and SLESS was 0.738. SLESS/SLAQ scale items (Raynaud’s phenomenon, rash, fever, easy bruising, hair loss) were significantly more associated with SLE than FM, while the reverse was true for headache, abdominal pain, paresthesias/stroke, fatigue, cognitive problems, and muscle pain or weakness. There was no evidence of disproportionate symptom-reporting associated with fibromyalgia-ness. Self-reported SLE was associated with an increased prevalence of FM that was unconfirmed by physicians, compared to SLE confirmed by physicians.

Conclusion

The prevalence of FM in SLE is minimally increased compared with its prevalence in patients with arthritis. Fibromyalgia-ness does not bias the SLESS and should not bias SLE assessments, including the SLAQ.
Inhibition of Src Homology 2 Domain-Containing Protein Tyrosine Phosphatase Substrate-1 Reduces the Severity of Collagen-Induced Arthritis
Authors: TANAKA KONAGI , HORIKAWA TATSUYA , SUZUKI SATSUKI , KITAURA KAZUTAKA , WATANABE JUNKO , GOTOH AKITO , SHIOBARA NORIYUKI , ITOH TSUNETOSHI , YAMANE SHOJI , SUZUKI RYUJI , FUKUI NAOSHI , OCHI TAKAHIRO
Published: November 2008

Objective

To investigate whether the blockade of Src homology 2 domain-containing protein tyrosine phosphatase substrate-1 (SHPS-1) has any therapeutic effects on rheumatoid arthritis.

Methods

A functional blocking monoclonal antibody for SHPS-1 (anti-SHPS-1 mAb) was administered at various doses to collagen-induced arthritis (CIA) mice, and severity of the arthritis was evaluated by clinical and histological scores of the limbs. To clarify the mechanisms of action of the antibody, the serum concentration of anti-type II collagen antibody was measured in those mice, and in vitro experiments were conducted to determine the effects of the antibody on the induction of osteoclasts and the release of cytokines from mouse spleen cells.

Results

Compared with mice given control IgG, the administration of anti-SHPS-1 mAb significantly reduced the severity of inflammation and destruction of bone and cartilage in CIA mice. This therapeutic effect was observed even when the antibody treatment was started after the onset of arthritis. The appearance of anti-type II collagen antibody in CIA mice was not altered by the antibody treatment. In in vitro experiments, the anti-SHPS-1 mAb significantly inhibited osteoclastogenesis of bone marrow cells, and significantly reduced the release of interleukin 1β (IL-1β), IL-2, IL- 12, interferon-γ, and tumor necrosis factor-α, but not that of IL-4 or IL-10, from the spleen cells after stimulation with concanavalin A.

Conclusion

Administration of a monoclonal antibody for SHPS-1 reduced the severity of arthritis in CIA mice. Regulation of biological functions of SHPS-1 may be a novel and potent strategy to treat patients with rheumatoid arthritis.
Cost Comparison Between Mycophenolate Mofetil and Cyclophosphamide-Azathioprine in the Treatment of Lupus Nephritis
Authors: TSE KAI CHUNG , TANG COLIN S.O. , LAM MAN FAI , YAP DESMOND Y.H. , CHAN TAK MAO
Published: November 2008

Objective.

To compare the healthcare expenditure associated with mycophenolate mofetil (MMF)-based immunosuppression in contrast to conventional therapy in patients with lupus nephritis.

Methods.

Our retrospective single-center study compared the major healthcare costs during the first 24 months of treatment incurred by immunosuppressive medications, hospitalization, and complications in patients with severe lupus nephritis who had been treated with prednisolone and either MMF or sequential cyclophosphamide induction followed by azathioprine maintenance (CTX-AZA).

Results.

Forty-four patients were studied (22 in each group). Baseline demographic and clinical measures, and remission rates after treatment, were similar between the 2 groups. Immunosuppressive drug cost was 13.6-fold higher in the MMF group (US$4168.3 ± 1176.5 per patient, compared with $285.0 ± 70.6 in the CTX-AZA group, mean difference $3883.2 ± 251.3; p < 0.001). MMF treatment was associated with a lower incidence of infections (12.0 episodes/1000 patient-months, compared with 32.4 in the CTX-AZA group; p = 0.035). Combined cost of hospitalization and treatment of infections was 82.5% lower in the MMF group (mean difference –2208.7 ± 1700.6; p = 0.120). Overall treatment expenditure on immunosuppressive drugs, hospitalization, and treatment of infections was 1.57-fold higher in the MMF group (mean US $4635.9 compared with $2961.5 in the CTX-AZA group; p < 0.001).

Conclusion.

While the cost of MMF treatment for severe lupus nephritis is much higher compared with CTX-AZA, the increased drug cost is partially offset by savings from the reduced incidence of complications.
Geroderma osteodysplastica maps to a 4 Mb locus on chromosome 1q24
Authors: Newman William G. , Clayton‐Smith Jill , Metcalfe Kay , Cole Rachel , Tartaglia Marco , Brancati Francesco , Morara Sara , Novelli Antonio , Liu Xiangdong , Siminovitch Katherine A. , Mundlos Stefan , Tassabehji May , Black Graeme C.M.
Published: November 2008

Important insights into the etiology of osteoporosis have been gained by the study of single gene disorders, including osteogenesis imperfecta. We report on the genetic mapping of geroderma osteodysplastica (GO), a rare autosomal recessive disorder of the connective tissue, characterized by wrinkly skin and severe osteoporosis. We undertook autozygosity mapping in one Libyan and four consanguineous Pakistani families with a total of 10 affected individuals to define a 4 Mb homozygous region on chromosome 1q24, which harbors the GO causative gene. No obvious candidate genes that encode known protein constituents of the extracellular matrix are found in the linked region. Importantly, our study demonstrates that GO is not allelic to wrinkly skin syndrome caused by mutations in ATP6V0A2. © 2008 Wiley‐Liss, Inc.
Paternal somatic mosaicism of a TGFBR2 mutation transmitting to an affected son with Loeys–Dietz syndrome
Authors: Watanabe Yoriko , Sakai Haruya , Nishimura Akira , Miyake Noriko , Saitsu Hirotomo , Mizuguchi Takeshi , Matsumoto Naomichi
Published: November 2008

We report on somatic mosaicism of a TGFBR2 missense mutation, c.1336G > A (D446N). The affected son with the heterozygous mutation was previously reported [Sakai et al. (2006); Am J Med Genet A 140A:1719–1725]. Further evaluation indicates his clinical condition is Loeys–Dietz syndrome. Parental blood samples were studied to confirm whether the propositus' mutation was a de novo change, and suggested a trace of the mutation in the father. DNAs extracted from blood leukocytes, buccal cells, hair root cells, and nails in the father indicated 52%, 25%, 0%, and 35% of cells harbored the mutation, respectively. This is the first detailed report of somatic mosaicism of a TGFBR2 mutation. © 2008 Wiley‐Liss, Inc.
Navajo microvillous inclusion disease is due to a mutation inMYO5B
Authors: Erickson Robert P. , Larson‐Thomé Katherine , Valenzuela Robert K. , Whitaker Stacia E. , Shub Mitchell D.
Published: November 2008

Microvillous Inclusion Disease (MID) is a rare, autosomal recessive gastrointestinal disease of increased frequency among the Navajos. Previous work has shown a deficiency of RAB8 in one Japanese patient, while homozygous mutations inMYO5Bwere found in 7 of 10 mostly Middle Eastern families. We have identified a shared homozygous mutation inMYO5Bin seven affected Navajos with the expected heterozygosity in five parents. We have developed a simple restriction enzyme based assay that allows for rapid screening for this mutation. © 2008 Wiley‐Liss, Inc.
Conversion of iminoacyl quinolinylpalladium (II) complexes into novel oxo‐pyrrolo[3,4‐b] quinolines via depalladation reactions
Authors: Hamad Elgazwy Abdel‐Sattar S.
Published: November 2008

Oxidative addition reactions of quinolines 1a, b with Pd(dba)2 in the presence of PPh3 (1:2) in acetone gave dinuclear palladium complexes [Pd(C,N‐2‐C9 H4N‐CHO‐3‐R‐6)Cl(PPh3)]2 [(R = H (2a), R = OMe (2b), which were reacted with isocyanide XyNC (Xy = 2,6‐Me2C6H3) to give novel iminoacyl quinolinylpalladium complexes 3a, b in good yields (81 and 77%). Cyclopalladated complexes3a, b were also obtained in low yields (39 and 33.5%) via one‐pot reaction of 1a, b with isonitrile XyNC:Pd(dba)2 (4:1). The reaction of 3a,b with Tl(TfO) (TfO = triflate, CF3SO3) in the presence of H2O or EtOH causes depalladation reactions of complexes to provide the corresponding organic compounds 4a, b, 5a, b and 6a, b in yields of 41, 27 and 18 − 19%, respectively. The products were characterized by satisfactory elemental analyses and spectral studies (IR, 1H, 13C and 31P NMR). The crystal structures 2a, 3a and3b were determined by X‐ray diffraction studies. Copyright © 2008 John Wiley & Sons, Ltd.
Estimation of reinforcement in compatibilized polypropylene nanocomposites by extensional rheology
Authors: Laske Stephan , Kracalik Milan , Gschweitl Michael , Feuchter Michael , Maier Günther , Pinter Gerald , Thomann Ralf , Friesenbichler Walter , Langecker Günter Rüdiger
Published: November 2008

Structural characterization in polymer nanocomposites is usually performed using X‐ray scattering and microscopic techniques, whereas the improvements in processing and mechanical properties are commonly investigated by rotational rheometry and tensile testing. However, all of these techniques are time consuming and require quite expensive scientific equipment. It has been shown that a fast and efficient way of estimating the level of reinforcement in polymer nanocomposites can be performed by melt extensional rheology, because it is possible to correlate the level of melt strength with mechanical properties, which reflect both the 3D network formed by the clay platelets/polymer chains as well as final molecular structure in the filled system. The physical network made of silicate filler and polymer matrix has been evaluated by X‐ray diffraction and transmission electron microscopy. Extensional rheometry and tensile testing have been used to measure efficiency of the compatibilizer amount in a polypropylene‐nanoclay system. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of the chemical characteristics of mesoporous silica MCM‐41 on morphological, thermal, and rheological properties of composites based on polystyrene
Authors: Pérez León D. , López Juan F. , Orozco Víctor H. , Kyu Thein , López Betty L.
Published: November 2008

Mesoporous silica nanoparticles (MCM‐41) with an average diameter of ∼ 20 nm were synthesized by a sol‐gel method using binary surfactant system. Polystyrene (PS) composites containing mesoporous silica nanoparticles were prepared by in situ polymerization of styrene monomers. Similar in situ polymerized PS composites were prepared based on the modified silica functionalized with methyl and vinyl groups. The effects of silylation on thermal and rheological properties of the PS/silica composites are investigated. Of particular importance is that the in situ polymerization of monomers within the mesoporous silica may trap some polymer chains, if not all, thereby affording a greater physical interaction between polymer and the porous fillers, whereas the chemical modification of silica surface promotes the polymer–filler interaction, which in turn enhances the thermal stability of composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Fatty Acid Binding Receptors and Their Physiological Role in Type 2 Diabetes
Authors: Swaminath Gayathri
Published: November 2008

G‐protein‐coupled receptors (GPCRs) respond to various physiological ligands such as photons, ions, and small molecules that include amines, fatty acids, and amino acids to peptides, proteins and steroids. Therefore, this family of proteins represents an attractive target for biopharmaceutical research [1]. The physiological role of fatty acids and other lipid molecules as important signal mediators is well studied in various metabolic pathways [2]. Acute administration of free fatty acids (FFAs) stimulates insulin release. Conversely, chronic exposure to high levels of free fatty acids leads to impairment of β cell function and lipotoxicity. However, the receptors through which these fatty acids and lipids act were unknown, until the identification of fatty acid binding receptors: GPR40, GPR41, GPR43, and GPR119. Based on their tissue‐expression profile, and pharmacologic analysis, the fatty acid binding receptors along with lipid binding receptor GPR119 are linked to diabetes and obesity. They play a critical role in the metabolic regulation of insulin release and glucose homeostasis. In this review, the mechanism of receptor activation, pharmacology, and the physiological functions of the fatty acid binding receptors will be discussed.
How do we evaluate future gambles? Experimental evidence on path dependency in risky intertemporal choice
Authors: Öncüler Ayse , Onay Selcuk
Published: November 2008

This study reports three experiments which demonstrate path dependency in risky intertemporal choice. Consider a lottery to be resolved and paid in a future time period. One can obtain the present value of this lottery in three different ways: (1) eliciting directly the present certainty equivalent (CE) of the future lottery (direct path); (2) eliciting the future CE and then discounting this amount to the present (risk‐time path); and (3) eliciting the present value of the risky prospect and then determining the CE of this current lottery (time‐risk path). Standard rational choice models such as the discounted expected utility model, assume a multiplicative model, where all three methods mentioned above would yield the same value. We conducted three studies to examine if this is the case: Experiments 1 and 2 were based on a set of matching‐task questions and Experiment 3 used a process‐tracing design to analyze the natural sequence of decision making by the subjects. These three studies show that the evaluation of future gambles is path‐dependent. The present values elicited under the time‐risk and direct paths are, on average, higher than those reported under the risk‐time path. In addition, we found evidence for a two‐stage evaluation of risky future prospects: When evaluating a future gamble, individuals first assess the present value of the gamble (time discounting) and then they determine a certainty equivalent (probability discounting). Copyright © 2008 John Wiley & Sons, Ltd.
Recalcitrant in‐stent restenosis of the celiac trunk treated by drug‐eluting stent
Authors: Visconti Gabriella , Taranto Domenico , Briguori Carlo
Published: November 2008

Stent implantation is an alternative, safe, and reliable strategy for the treatment of chronic mesenteric ischemia, especially for patients at high surgical risk. However, in‐stent restenosis (the Achille's hill of bare metal stent) may occur in up to 20% of cases at 6 months and 53% at 1 year. We describe a case of celiac trunk stenosis treated by bare metal stent complicated by recalcitrant in‐stent restenosis and treated by paclitaxel‐eluting stent implantation. © 2008 Wiley‐Liss, Inc.
Incidence, predictors, and outcome of reinfarction and stent thrombosis within one year after primary percutaneous coronary intervention for ST‐elevation myocardial infarction
Authors: Fokkema M.L. , van der Vleuten P.A. , Vlaar P.J. , Svilaas T. , Zijlstra F.
Published: November 2008

Background:

Reinfarction and stent thrombosis are major complications after primary percutaneous coronary intervention (PCI) for ST‐elevation myocardial infarction (STEMI).

Objective:

We sought to investigate the incidence, predictors, and outcome of reinfarction and stent thrombosis in a contemporary cohort of STEMI patients.

Methods:

Reinfarction and stent thrombosis within 1 year after primary PCI for STEMI were analyzed in the Thrombus Aspiration during Percutaneous coronary intervention in Acute myocardial infarction Study (TAPAS).

Results:

Reinfarction was observed in 3.4% (34/995) of patients within 1 year after primary PCI. Angiographic evidence of stent thrombosis was observed in 15/34 (44.1%). During the index primary PCI, intra‐aortic balloon counterpulsation was used in 10/32 (31.3%) patients with and 47/900 (5.2%) without reinfarction (P < 0.001). After the index primary PCI, thrombus was visible in 6/34 (17.7%) with reinfarction when compared with that in 25/952 (2.6%) without reinfarction (P < 0.001), and complete ST‐segment resolution in 8/33 (24.2%) compared with that in 462/892 (51.8%, P = 0.002). Mortality at 1 year after the index PCI was higher after reinfarction: 6/34 (17.7%) compared with 53/961 (5.5%, P = 0.003). Patients with stent thrombosis showed myocardial blush grade 0–1 in 11/15 (73.3%) cases, distal embolization in 8/15 (53.3%), and a mortality at 1 year of 4/15 (26.7%).

Conclusions:

In contemporary practice with primary PCI and triple antiplatelet therapy for STEMI, the incidence of reinfarction is low. Outcome characteristics after the index PCI were important determinants of reinfarction. However, reinfarction was associated with poor prognosis, and in particular patients with stent thrombosis had poor outcome. © 2009 Wiley‐Liss, Inc.
Radial compression guided by mean artery pressure versus standard compression with a pneumatic device (RACOMAP)
Authors: Cubero Jose M. , Lombardo Juan , Pedrosa Carmela , Diaz‐Bejarano Dolores , Sanchez Blanca , Fernandez Vicente , Gomez Coral , Vazquez Rafael , Molano Francisco J. , Pastor Luis F.
Published: November 2008

Background: Transradial access is the approach of choice in many laboratories for diagnostic coronariography or percutaneous coronary interventions (PCI) because of its lower vascular complication rate than the femoral approach. However, this approach has a higher rate (5–10%) of asymptomatic radial artery (RA) occlusion. Methods: We conducted a prospective, controlled, single‐centre trial study. We investigated whether the pneumatic compression (using “TR Band of Terumo®”) of the radial artery guided by the mean artery pressure (MAP) after the procedure (group A) is efficient in reducing radial occlusion in patients under a coronary angiography by transradial access for diagnostic coronariography or PCI compared to use of standard procedure (group B, 15 cm3 of air in the device). Results: The study was suspended after analyzing the results of 50% of the scheduled patients. An analysis of the results of 351 consecutive random patients in Group A showed significantly (P = 0.0001) lower rate (1.1%) of occlusion than Group B (12.0%) without significant differences in the rate of other complications. Other variables associated with RA occlusion in univariate analysis were previous or active smoker (P < 0.04), absence of anti‐aggregant treatment (P < 0.04), and the presence of RA flow postprocedure (PFP, P < 0.001). Independent predictors with logistic regression analysis were PFP (HR = 0.06, 95% CI 0.01–0.2), presence of hematoma (HR = 3.7, 95% CI 1.2–11.0), and standard pneumatic compression in group B patients (HR = 18.8, 95% CI 3.8–92.2). Conclusions: Use of pneumatic compression guided by MAP is safe and efficient, and it can significantly lower the incidence of radial artery occlusion. © 2009 Wiley‐Liss, Inc.
Control of H‐ and J‐Type π Stacking by Peripheral Alkyl Chains and Self‐Sorting Phenomena in Perylene Bisimide Homo‐ and Heteroaggregates
Authors: Ghosh Suhrit , Li Xue‐Qing , Stepanenko Vladimir , Würthner Frank
Published: November 2008

The synthesis, self‐assembly, and gelation ability of a series of organogelators based on perylene bisimide (PBI) dyes containing amide groups at imide positions are reported. The synergetic effect of intermolecular hydrogen bonding among the amide functionalities and π–π stacking between the PBI units directs the formation of the self‐assembled structure in solution, which beyond a certain concentration results in gelation. Effects of different peripheral alkyl substituents on the self‐assembly were studied by solvent‐ and temperature‐dependent UV‐visible and circular dichroism (CD) spectroscopy. PBI derivatives containing linear alkyl side chains in the periphery formed H‐type π stacks and red gels, whereas by introducing branched alkyl chains the formation of J‐type π stacks and green gels could be achieved. Sterically demanding substituents, in particular, the 2‐ethylhexyl group completely suppressed the π stacking. Coaggregation studies with H‐ and J‐aggregating chromophores revealed the formation of solely H‐type π stacks containing both precursor molecules at a lower mole fraction of J‐aggregating chromophore. Beyond a critical composition of the two chromophores, mixed H‐aggregate and J‐aggregate were formed simultaneously, which points to a self‐sorting process. The versatility of the gelators is strongly dependent on the length and nature of the peripheral alkyl substituents. CD spectroscopic studies revealed a preferential helicity of the aggregates of PBI building blocks bearing chiral side chains. Even for achiral PBI derivatives, the utilization of chiral solvents such as (R)‐ or (S)‐limonene was effective in preferential population of one‐handed helical fibers. AFM studies revealed the formation of helical fibers from all the present PBI gelators, irrespective of the presence of chiral or achiral side chains. Furthermore, vortex flow was found to be effective in macroscopic orientation of the aggregates as evidenced from the origin of CD signals from aggregates of achiral PBI molecules.
Safety of Spironolactone Use in Ambulatory Heart Failure Patients
Authors: Lopes Ricardo J. , Lourenço Ana Patricia , Mascarenhas Joana , Azevedo Ana , Bettencourt Paulo
Published: November 2008

Background

Since the Randomized Aldactone Evaluation Study (RALES), the use of spironolactone is recommended in systolic heart failure (HF) patients that have been in New York Heart Association (NYHA) class III or IV. There is limited information on the use, side effects, and withdrawal rate of spironolactone in routine clinical practice.

Hypothesis

Side effects related to spironolactone use are more common than reported in clinical trials.

Methods

Patients who had moderate to severe left ventricular systolic dysfunction (LVSD) under optimized medical therapy were included. We introduced spironolactone in those with serum potassium (K+) ≤ 5 meq/L, and serum creatinine (Cr) ≤ 2.5 mg/dL. Spironolactone was withdrawn if serum K + ≥ 5.5 meq/L, serum Cr increased more than 30%− 50% of the baseline value, and/or if the patient had gynecomastia.

Results

We selected 134 patients followed in an HF clinic. In our sample, 56.7% of the patients (76 out of 134) were currently or had formerly been on spironolactone therapy. The rate of spironolactone withdrawal was 25% (19 out of 76). Reasons for suspension were hyperkalemia (17.1%), renal function deterioration (14.5%), gynecomastia (5.3% of males), and other reasons (1.3%).

Conclusion

Spironolactone side effects are common and are mostly related to effects on the angiotensin‐aldosterone axis. Our results reinforce the need to closely monitor serum K+ and Cr levels in patients treated with spironolactone, as its side effects are more common than reported in clinical trials. Copyright © 2008 Wiley Periodicals, Inc.
Tetralogy of Fallot: The Oldest Reported Survivor of Brock's Procedure
Authors: Manchikalapudi Rama Bindu , Klugherz Bruce D.
Published: November 2008

We report the case of a 79‐y‐old male with Tetralogy of Fallot (TOF) who underwent Brock's procedure in his twenties and has survived event‐free. Brock's procedure, which entailed infundibular resection and pulmonary valvotomy, has been associated with complications including the need for re‐operation, pulmonary regurgitation, and biventricular failure. Copyright © 2008 Wiley Periodicals, Inc.
Gender Differences on Brachial Flow‐mediated Dilation and Carotid Intima‐media Thickness for Prediction of Spontaneous Cardiovascular Events
Authors: Hu Rui , Wang Wei‐Qun , Lau Chu‐Pak , Tse Hung‐Fat
Published: November 2008

Background

Impaired brachial flow‐mediated dilation (FMD) and increased carotid intima‐media thickness (IMT) are associated with increased risk of cardiovascular events.

Methods

We measured brachial FMD and a mean of 12 sites maximum carotid IMT (mmIMT) in 279 patients (mean age 62 ± 12 y; 163 men) admitted for coronary angiography due to chest pain.

Hypothesis

There are gender differences in the predictive values of FMD and IMT for cardiovascular events.

Results

Univariable analysis showed that impaired FMD (p < 0.001), but not increased mmIMT (p = 0.056), significantly predicted spontaneous cardiovascular events. After adjusting for the extent of coronary artery disease (CAD) and other clinical variables, age (heart rate [HR] 1.05, 95% confidence interval [CI]: 1.01‐1.09, p = 0.017) and FMD (HR 0.85, 95% CI: 0.75‐0.97, p = 0.012) were independent predictors for cardiovascular events. A total of 148 (53%) patients had CAD (≥50% diameter stenosis). Over a median follow‐up of 16 mo, 36 (12.9%) patients experienced spontaneous cardiovascular events (cardiovascular death, stroke, acute myocardial infarction [MI], unstable angina pectoris, and congestive heart failure [HF]). Women were more likely than men to develop cardiovascular events in patients without significant CAD (11.9% versus 1.6%, odds ratio [OR] = 8.54, p = 0.033), but not in those patients with CAD (20.4 % versus 17.2%, OR = 1.24, p = 0.66). Moreover, women accounted for 8 (88.9%) events in non‐CAD patients. Furthermore, impaired FMD predicted the occurrence of cardiovascular events in both men and women (p < 0.05).

Conclusion

Brachial FMD, rather than carotid IMT, was an independent predictor for cardiovascular events after adjusting for the extent of CAD. Moreover, impaired brachial endothelial function in women without significant CAD was associated with an increased risk of spontaneous cardiovascular events. Copyright © 2008 Wiley Periodicals, Inc.
Prevalence of Emerging Cardiovascular Risk Factors in Younger Individuals with a Family History of Premature Coronary Heart Disease and Low Framingham Risk Score
Authors: Sailam Vivek , Karalis Dean G. , Agarwal Ashish , Alani Firas , Galardi Susan , Covalesky Veronica , Athanassious Christian
Published: November 2008

Introduction

The purpose of this study was to assess the prevalence of emerging cardiac risk factors in individuals with a family history of premature coronary heart disease (CHD) and who were predicted to be low‐risk for cardiovascular (CV) disease based on their Framingham risk score.

Methods

We prospectively evaluated 89 younger men and women with a family history of premature CHD and who had a low Framingham risk score. Patients with CHD or CHD equivalents were excluded. All patients were screened for emerging clinical and lipid risk factors.

Results

Coronary calcium was present in 38% of patients and C‐reactive protein > 3 mg/dl was present in 24% of patients. Low levels of high‐density lipoprotein (HDL2) cholesterol were the most prevalent emerging lipid risk factor and was present in 72% of the study group. More individuals had low levels of HDL2 than total HDL (34% versus 71%; p‐value =0.001). Triglyceride‐ (TG)‐rich remnant lipoproteins were present in 49% of patients.

Conclusions

The Framingham risk score poorly predicts CV risk in younger healthy persons with a family history of premature CHD. The prevalence of subclinical CHD and emerging clinical and lipid risk factors is high in these patients. The most prevalent lipid risk factor was low levels of HDL2. Individuals with a family history of premature CHD may benefit from screening for emerging risk factors to better assess their CV risk. Copyright © 2008 Wiley Periodicals, Inc.
Stereocontrolled Synthesis and Pharmacological Evaluation of Azetidine‐2,3‐Dicarboxylic Acids at NMDA Receptors
Authors: Sivaprakasam Mangaleswaran , Hansen Kasper B. , David Olivier , Nielsen Birgitte , Traynelis Stephen F. , Clausen Rasmus P. , Couty François , Bunch Lennart
Published: November 2008

The four stereoisomers of azetidine‐2,3‐dicaroxylic acid (L‐trans‐ADC,L‐cis‐ADC,D‐trans‐ADC, andD‐cis‐ADC) were synthesized in a stereocontrolled fashion following two distinct strategies: one providing the twocis‐ADC enantiomers and one giving access to the twotrans‐ADC enantiomers. The four azetidinic amino acids were characterized in a radioligand binding assay ([3H]CGP39653) at native NMDA receptors:L‐trans‐ADC showed the highest affinity (Ki=10 μM) followed by theD‐cis‐ADC stereoisomer (21 μM). In contrast, the two analoguesL‐cis‐ADC andD‐trans‐ADC were low‐affinity ligands (>100 and 90 μM, respectively). Electrophysiological characterization of the ADC compounds at the four NMDA receptor subtypes NR1/NR2A, NR1/NR2B, NR1/NR2C, and NR1/NR2D expressed inXenopus oocytesshowed thatL‐trans‐ADC displayed the highest agonist potency at NR1/NR2D (EC50=50 μM), which was 9.4‐, 3.4‐, and 1.9‐fold higher than the respective potencies at NR1/NR2A–C.D‐cis‐ADC was shown to be a partial agonist at NR1/NR2C and NR1/NR2D with medium‐range micromolar potencies (EC50=720 and 230 μM, respectively). A subsequent in silico ligand–protein docking study suggested an unusual binding mode for these amino acids in the agonist binding site.
Subcellular targeting of kappa‐opioid receptors in the rat nucleus locus coeruleus
Authors: Reyes B.A.S. , Chavkin Charles , van Bockstaele E.J.
Published: November 2008

The dynorphin (DYN)‐kappa opioid receptor (κOR) system has been implicated in stress modulation, depression, and relapse to drug‐seeking behaviors. Previous anatomical and physiological data have indicated that the noradrenergic nucleus locus coeruleus (LC) is one site at which DYN may contribute to these effects. Using light microscopy, immunofluorescence, and electron microscopy, the present study investigated the cellular substrates for pre‐ and postsynaptic interactions of κOR in the LC. Dual immunocytochemical labeling for κOR and tyrosine hydroxylase (TH) or κOR and preprodynorphin (ppDYN) was examined in the same section of tissue. Light microscopic analysis revealed prominent κOR immunoreactivity in the nuclear core of the LC and in the peri‐coerulear region where noradrenergic dendrites extend. Fluorescence and electron microscopy revealed κOR immunoreactivity within TH‐immunoreactive somata and dendrites in the LC as well as localized to ppDYN‐immunoreactive processes. In sections processed for κOR and TH, ≈29% (200/688) of the κOR‐containing axon terminals identified targeted TH‐containing profiles. Approximately 49% (98/200) of the κOR‐labeled axon terminals formed asymmetric synapses with TH‐labeled dendrites. Sections processed for κOR and ppDYN showed that, of the axon terminals exhibiting κOR, 47% (223/477) also exhibited ppDYN. These findings indicate that κORs are poised to modulate LC activity by their localization to somata and dendrites. Furthermore, κORs are strategically localized to presynaptically modulate DYN afferent input to catecholamine‐containing neurons in the LC. These data add to the growing literature showing that κORs can modulate diverse afferent signaling to the LC. J. Comp. Neurol. 512:419–431, 2009. © 2008 Wiley‐Liss, Inc.