bluuebunny/crossref_metadata_2025 huggingface dataset:
New Means of Canine Leishmaniasis Transmission in North America: The Possibility of Transmission to Humans Still Unknown
Authors: Petersen Christine A.
Published: June 2009

At present it is not possible to determine in advance the outcome ofLeishmania infantuminfection. Canine Visceral Leishmaniasis (VL), caused byLe. infantum, is a natural disease process which offers a insight into the interaction of the host and resultant disease outcome. Canine VL results in the same altered pathophysiology and immunodysregulation seen in humans. VL in US dogs is likely to be transmitted primarily via nontraditional, nonvector means. VL mediated byLe. infantumis endemic in U.S. Foxhound dogs, with vertical transmission likely to be the novel primary means of transmission. This population of dogs offers an opportunity to identify host factors of natural disease. Prevention of human clinical visceral leishmaniasis can occur only by better understanding the disease ecology of the primary reservoir host: the dog.
Magnetostratigraphy and Tectonic Rotation of the Eocene-Oligocene Makah and Hoko River Formations, Northwest Washington, USA
Authors: Prothero Donald R. , Draus Elizabeth , Burns Casey
Published: June 2009

The Eocene-Oligocene Makah Formation and subjacent middle Eocene Hoko River Formation of the northwestern Olympic Peninsula, Washington, yield mollusks, crustaceans, foraminifera, and early neocete whales; their age has never been precisely established. We sampled several sections; most samples showed a stable single-component remanence held largely in magnetite and passed a Class I reversal test. The upper Refugian (late Eocene) and lower Zemorrian (early Oligocene) rocks at Baada Point correlate with Chron C13r (33.7–34.7 Ma) and Chron C12r (30–33 Ma). The Ozette Highway section of the Makah Formation spanned the early Refugian to late Refugian, with a sequence that correlates with Chrons C15r-C13r (33.7–35.3 Ma), and a long reversed early Zemorrian section that correlates with Chron C12r (30–33 Ma). The type section of the Hoko River Formation correlates with Chron C18r (40.0–41.2 Ma). The area sampled shows about45∘of post-Oligocene counterclockwise tectonic rotation, consistent with results obtained from the Eocene-Oligocene rocks in the region.
Immune versus thrombotic stimulation of platelets differentially regulates signalling pathways, intracellular protein-protein interactions, and α-granule release
Authors: Rex Sybille , Beaulieu Lea M. , Perlman David H. , Vitseva Olga , Blair Price S. , McComb Mark E. , Costello Catherine E. , Freedman Jane E.
Published: June 2009

In addition to haemostasis, platelets mediate inflammation and clearance of bacteria from the bloodstream. As with platelet-platelet interactions, platelet-bacteria interactions involve cytoskeletal rearrangements and release of granular content. Stimulation of the immune Toll-like receptor 2 (TLR2) on the platelet surface, activates phosphoinositide-3-kinase (PI3K) and causes platelet activation and plateletdependent thrombosis. It remains unknown if platelet activation by immune versus thrombotic pathways leads to the differential regulation of signal transduction, protein-protein interactions, and α-granule release, and the physiological relevance of these potential differences. We investigated these processes after immune versus thrombotic platelet stimulation. We examined selected signalling pathways and found that phosphorylation kinetics of Akt, ERK1/2 and p38 differed dramatically between agonists. Next, we investigated platelet protein-protein interactions by mass spectrometry (MS)-based proteomics specifically targeting cytosolic factor XIIIa (FXIIIa) because of its function as a cytoskeleton-crosslinking protein whose binding partners have limited characterisation. Four FXIIIa-binding proteins were identified, two of which are novel interactions: FXIIIa-focal adhesion kinase (FAK) and FXIIIa-gelsolin. The binding of FAK to FXIIIa was found to be altered differentially by immune versus thrombotic stimulation. Lastly, we studied the effect of thrombin versus Pam3CSK4 stimulation on α-granule release and observed differential release patterns for selected granule proteins and decreased fibrin clot formation compared with thrombin. The inhibition of PI3K caused a decrease in protein release after Pam3CSK4
-but not after thrombin-stimulation. In summary, stimulation of platelets by either thrombotic or immune receptors leads to markedly different signalling responses and granular protein release consistent with differential contribution to coagulation and thrombosis.
Demonstration of heterodimeric fibrinogen molecules partially conjugated with albumin in a novel dysfibrinogen: Fibrinogen Mannheim V
Authors: M.George Peter , Borggrefe Martin , Neumaier Michael , Brennan Stephen O. , Dempfle Carl-Erik
Published: June 2009

A 30-year-old female experienced three miscarriages in early pregnancy. Extensive laboratory screening showed a low plasma fibrinogen level of approximately 1 g/l detected by PT-derived fibrinogen assay.The fibrinogen level in the immunological assay was 3 g/l.The functional Clauss assay yielded an intermediate result of 1.78 g/l. During her fourth and fifth pregnancy, the patient received fibrinogen concentrates (Haemocomplettan, CLS Behring, Marburg, Germany), starting with 4 grams of human fibrinogen, followed by 2 grams every second day until the 15th week of pregnancy.The further course of these pregnancies was uneventful. SDS-PAGE and immunoblotting showed doublet bands in the positions of the high-molecular weight (HMW)-and lowmolecular-weight (LMW)-fibrinogen, a single LMW’ fibrinogen band, plus additional bands with higher molecular weight than HMW-fibrinogen, which were also reactive with anti-human serum albumin (HSA) antiserum. These bands correspond to variant fibrinogen conjugated with albumin. Reduced SDS-PAGE and immunoblotting using polyclonal anti-fibrinopeptide A antiserum disclosed one additional Aα-chain band with lower molecular weight. Amplification and sequencing of exon 5 of the α gene indicated heterozygosity for a novel single nucleotide deletion at codon Aα494 (C1537delA). His494 is replaced by Pro and this is followed by 23 (LMKLPSSTLPQLEKHSQ VSSHLC) new amino acids before premature truncation after Cys517, yielding a free C-terminal cysteine, which may link with albumin.This new fibrinogen mutation, leads to a balanced array of homo- and heterodimeric fibrinogen molecules, some of which are conjugated to albumin.
The absence of angiopoietin-2 leads to abnormal vascular maturation and persistent proliferative retinopathy
Authors: Feng Yuxi , Hagen Franziska , Wang Yumei , Beck Susanne , Schreiter Kay , Pfister Frederick , Hoffmann Sigrid , Wagner Patrick , Seeliger Mathias , Molema Grietje , Deutsch Urban , Hammes Hans-Peter
Published: June 2009

Angiopoietin-2 (Ang-2) antagonises the maturing effect of angiopoietin-1 (Ang-1) on blood vessels, and cooperates with VEGF to induce neovascularisation. In knockout mice,Ang-2 displayed a specific role in postnatal angiogenic remodelling. Here, we demonstrate that mice deficient in Ang-2 fail to form a proper spatial retinal vascular network. The retinal vasculature was characterised by reduced large vessel numbers and defects forming the superficial periphery mostly on the arteriolar site, and the secondary and tertiary deep capillary network. Hypoxia in the retinal periphery induced a four-fold VEGF upregulation and active endothelial proliferation for up to 60 days. Concomitantly, retinal digest preparations showed increased arteriolar (+33%) and capillary diameters (+90%), and fluorescein angiograms revealed leakiness of neovascular front. At one year of age, persistent preretinal vessels were non-leaky in accordance with a relative increase in the ratio of Ang-1 to VEGF.Taken together, the data suggest that Ang-2 has an important function in the spatial configuration of the three-dimensional retinal vasculature. Secondarily, prolonged VEGF activity results in a model of persistent proliferative retinopathy.
Prophylactic fibrinogen infusion reduces bleeding after coronary artery bypass surgery
Authors: Karlsson Martin , Ternström Lisa , Hyllner Monica , Baghaei Fariba , Flinck Agneta , Skrtic Stanko , Jeppsson Anders
Published: June 2009

It has been suggested that preoperative fibrinogen plasma concentration is independently associated to postoperative blood loss after cardiac surgery.Theoretically, prophylactic infusion of fibrinogen concentrate may thus reduce postoperative bleeding, but this has not previously been investigated. Twenty elective coronary artery bypass graft (CABG) patients with preoperative plasma fibrinogen levels <3.8 g/l were included in a prospective randomised pilot study. Patients were randomised to receive an infusion of 2 g fibrinogen concentrate (FIB group) or no infusion before surgery (control group). Primary endpoint was safety with clinical adverse events and graft occlusion assessed by multi-slice computed tomography. Predefined secondary endpoints were postoperative blood loss, blood transfusions, haemoglobin levels 24 hours (h) after surgery, and global haemostasis assessed with thromboelastometry, 2 and 24 hours after surgery. Infusion of 2 g fibrinogen concentrate increased plasma levels of fibrinogen by 0.6 ± 0.2 g/l.There were no clinically detectable adverse events of fibrinogen infusion.Computed tomography revealed one subclinical vein graft occlusion in the FIB group. Fibrinogen concentrate infusion reduced postoperative blood loss by 32% (565 ± 150 vs. 830 ± 268 ml/12 h, p=0.010). Haemoglobin concentration was significantly higher 24 h after surgery in the FIB group (110 ± 12 vs. 98 ± 8 g/l, p=0.018). Prophylactic fibrinogen concentrate infusion did not influence global postoperative haemostasis as assessed by thromboelastometry. In conclusion, in this pilot study preoperative fibrinogen concentrate infusion reduced bleeding after CABG without evidence of postoperative hypercoagulability. Larger studies are necessary to ensure safety and confirm efficacy of prophylactic fibrinogen treatment in cardiac surgery.
Differential inhibition of thrombin generation by vitamin K antagonists alone and associated with low-molecular-weight heparin
Authors: Gerotziafas Grigoris T. , Dupont Charlotte , Spyropoulos Alex C. , Hatmi Mohamed , Samama Meyer M. , Kiskinis Dimitris , Elalamy Ismail
Published: June 2009

Vitamin K antagonists (VKA) treatment starts with co-administration of low-molecular-weight heparin (LMWH). The anticoagulation induced by the two drugs is still not well determined. In the present study we used thrombin generation assay to evaluate the hypo-coagulation induced by treatment with VKA and by the combination of VKA with LMWH. Tissue factor triggered thrombin generation in platelet-poor plasma was assessed in samples from 15 healthy volunteers, 97 samples from patients treated with VKA and 41 samples from patients receiving enoxaparin and VKA. Patients were classified according to international normalised ratio (INR) level (<2, 2–3 and >3).In plasma samples from patients treated with VKA having INR 2–3 the inhibition of thrombin generation reached 50% compared to controls. In samples with INR>3 this inhibition was 80%. In samples from patients receiving both LMWH and VKA, thrombin generation was significantly decreased compared to the controls and VKA group. In samples with an INR 2–3 obtained from patients treated with LMWH and VKA, the inhibition of thrombin generation was similar to that observed in samples with an INR>3 obtained from VKA treated patients. Thrombin generation assay is sensitive to detect the global the anticoagulant effect produced by the association of LMWH and VKA. For equal INR dual anticoagulant treatment induces significantly more profound inhibition of thrombin generation compared to treatment with VKA alone. The clinical relevance of this observation merits to be studied in prospective studies in patients with defined indications of anticoagulant therapy.
Reduction of early vein graft thrombosis by tissue plasminogen activator gene transfer
Authors: Wyatt Marcella J. , Newby Andrew C. , Thomas Anita C.
Published: June 2009

Vein grafts are used to bypass coronary arterial stenosis, but many grafts thrombose soon after surgery. A model was developed in the pig to allow continuous measurement of blood flow and production of flow-restricting thrombi (cyclic flow reductions; CFRs). Saphenous vein lumen was exposed to adenovirus ex vivo, to over-express human tissue plasminogen activator (h-tPA), with β-galactosidase adenovirus as a control. The vein segmen ts were engrafted into carotid arteries and examined 0,1 or 3 days later (4–7 animals/group). Untransduced grafts examined on the day of surgery developed repeated CFRs at both normal and restricted flow, but their frequency declined in grafts examined after 3 days. Adenovirus transduction was evident as β-galactosidase or h-tPA expression 1 day after engraftment. Blood flow was increased 1.4-fold in h-tPA transduced grafts after 1 day [control 390 (280–510), h-tPA 550 (450–660) ml/min; p=0.02 (expressed as mean (95% confidence intervals)]. CFRs were less severe (p=0.002) in the h-tPA transduced grafts than β-galactosidase-transduced grafts. CFRs were also less frequent in unstenosed undamaged h-tPA grafts [control 17 (6.1–29), h-tPA 7.6 (1.7–14) CFR/hr; p=0.02], but this difference was reduced after damage or stenosis. CFRs formed faster in h-tPA than in β-galactosidase-transduced grafts [control 14 (11–17), h-tPA 23 (19–27) ml/min2; p<0.001], and resolved twofold faster [control 25 (22–30), h-tPA 48 (39–60) ml/min2; p<0.001]. Hence, in this model, local gene therapy with h-tPA increased graft blood flow and decreased measures of early graft thrombosis, namely quicker CFR resolution and decreased frequency and severity.
Laboratory criteria of the obstetrical antiphospholipid syndrome
Authors: Boinot Catherine , De Carolis Sara , Rovere-Querini Patrizia , Aurousseau Marie-Hélène , Allegri Flavio , Nicaise-Roland Pascale , Barra Anne , Botta Angela , Ambrozic Ales , Avcin Tadej , Tincani Angela , Boffa Marie-Claire
Published: June 2009

A debate on updating the laboratory criteria of antiphospholipid syndrome (APS) was recently opened in view to lower the risk of over diagnosis of the syndrome. Based on data related to thrombotic APS, it proposes the exclusion of anticardiolipin antibodies (aCL) and anti-beta2-glycoprotein 1 (a-β2-GPI) IgM detection. Here, we examine this possibility in a study which focuses on obstetrical APS (OAPS).We report new data on a prospective multicenter European cohort of 109 pregnant women having APS.Among them, 73 had purely obstetrical APS, not associated to autoimmune diseases or thrombosis. Isolated antibodies and isolated aCL positivity were present in 50/109 (46%) and in 34/109 (31%) of the women, respectively. An isolated a-β2-GPI IgM was present in three women.These results suggest that aCL and a-β2-GPI IgM cannot be dropped for the diagnosis and classification of OAPS.The low level of some antibodies associated with severe obstetrical complications raise the issue of keeping or not the same laboratory criteria for OAPS and for thrombotic APS and whether additional criteria after large prospective studies could further improve diagnosis.
Point-of-care monitoring of oral anticoagulation therapy in children
Authors: Greenway Anthea , Summerhayes Robyn , Newall Fiona , Burgess Janet , DeRosa Lydia , Monagle Paul , Ignjatovic Vera
Published: June 2009

Point-of-care (POC) monitoring of oral anticoagulation has been widely adopted in both paediatric and adult patients. A new POC system, the CoaguChek XS® has recently been developed to measure the international normalised ratio (INR) and may offer significant advantages. The CoaguChek XS® utilises a new method of electrochemical clot detection based on thrombin generation. This system has not been previously evaluated in children with reference to the laboratory gold standard, the prothrombin time using reference thromboplastin. It was the objective to compare values obtained by the CoaguChek XS® system with both the venous INR and the gold standard for anticoagulant monitoring, prothrombin time with reference thromboplastin (rTF/95).To evaluate the impact of testing using the Coagu-Chek XS® on clinical anticoagulant dosing decisions. Fifty paired venous INR and capillary CoaguChek XS® results were obtained from 31 children (aged up to 16 years).The laboratory gold standard, a manual prothrombin time with reference thromboplastin (rTF/95) was additionally performed on 26 samples. Correlation between the CoaguChek XS® result and the venous INR was r= 0.810. Agreement between the CoaguChek XS result and the reference INR was shown to be higher (r=0.95), in the subset analysed by this method. Correlation between the venous INR and reference INR was r=0.90. Despite changes to the methodology of testing with the CoaguChek XS® POC monitoring system, the accuracy of this method when compared with both the venous INR and gold standard reference INR was satisfactory. This resulted in infrequent changes to clinical decision making regarding anticoagulation
Megakaryocytes of patients with MYH9-related thrombocytopenia present an altered proplatelet formation
Authors: Malara Alessandro , Badalucco Stefania , Bozzi Valeria , Torti Mauro , Balduini Carlo L. , Balduini Alessandra , Pecci Alessandro
Published: June 2009

MYH9-related disease (MYH9-RD) is an autosomal-dominant thrombocytopenia caused by mutations of MYH9, the gene for the heavy chain of myosin-IIA. Pathogenesis of thrombocytopenia of MYH9-RD is unknown. Recent studies in mice demonstrated that myosin-IIA is an inhibitor of proplatelet formation (PPF), and suggested that it could be involved in the suppression of PPF exerted by megakaryocyte adhesion to type I collagen, which regulates the timing of platelet release within bone marrow. However, the consequences on PPF of the heterozygous mutations causative of the MYH9-RD have never been investigated. We studied the in-vitro PPF by megakaryocytes obtained from four patients carrying the p.D1424N or the p.R1933X mutations. We demonstrated that MYH9-RD megakaryocytes completely lose the physiologic suppression of proplatelet extension exerted by interaction with type I collagen, thus supporting the hypothesis that a premature platelet release within bone marrow contributes to pathogenesis of MYH9-related thrombocytopenia. Moreover, proplatelets extended by MYH9-RD megakaryocytes presented a significant defect in branching in secondary processes (p=0.001) and formed a significantly lower number of proplatelet tips (p=0.005). Since platelets are assembled at the level of proplatelet tips, this defect could further contribute to pathogenesis of thrombocytopenia of MYH9-RD patients.
Clinical and economic outcomes in patients at risk of venous thromboembolism receiving appropriate enoxaparin or unfractionated heparin prophylaxis
Authors: Lin Jay , Lenhart Greg , Schulman Kathy , Amin Alpesh
Published: June 2009

Clinical and economic outcomes were compared following appropriate prophylaxis with enoxaparin or unfractionated heparin (UFH) in a large, real-world population of US hospitalised medical and surgical patients at risk of venous thromboembolism (VTE). Discharges from the Thomson Reuters MarketScan® Hospital Drug Database (January 2004–March 2007) of patients aged ≥40 years, at risk of VTE according to the 7th American College of Chest Physicians (ACCP) guidelines, who spent ≥6 days in hospital and received appropriate ACCP-recommended enoxaparin or UFH prophylaxis were included. Patients with contraindications to anticoagulation were excluded. Hospital-acquired VTE, adverse events, and hospital costs for enoxaparin versus UFH were compared using univariate and multivariate analyses. Of the 5,136 discharges included, 4,014 (78%) received enoxaparin and 1,122 (22%) received UFH. Compared with UFH, enoxaparin was associated with significantly lower risk of hospital-acquired VTE (adjusted odds ratio [OR] 0.51, 95% confidence interval [CI] 0.30–0.86, p=0.012), pulmonary embolism (adjusted OR 0.33, 95% CI 0.14–0.79, p=0.013) or adverse events (adjusted OR 0.73, 95% CI 0.54–0.98, p=0.034). Total hospital costs per discharge were lower for enoxaparin (US $16,865 ± 10,979) than UFH (US $19,252 ± 14,970), with a mean difference of US $2,388 in favour of enoxaparin (p<0.001) (adjusted difference US $439, 95% CI US $ -39 to 909, p=0.072). In patients at risk of VTE, appropriate enoxaparin prophylaxis was associated with a reduction in hospital-acquired VTE, adverse events, and costs compared with appropriate UFH prophylaxis. Increased appropriate use of enoxaparin in patients at risk of VTE may help to reduce the clinical and economic burden of this condition.
Long-Term Outcome of Ablative Therapy of Postoperative Supraventricular Tachycardias in Patients With Univentricular Heart
Authors: de Groot Natasja M.S. , Lukac Peter , Blom Nico A. , van Kuijk Jan Peter , Pedersen Anders K. , Hansen Peter S. , Delacretaz Etienne , Schalij Martin J.
Published: June 2009

Background—

Catheter ablation has evolved as a possible curative treatment modality for supraventricular tachycardias (SVT) in patients with univentricular heart. However, the long-term outcome of ablation procedures is unknown. We evaluated the procedural and long-term outcome of ablative therapy of late postoperative SVT in patients with univentricular heart.

Methods and Results—

Patients with univentricular heart (n=19, 11 male; age, 29�9 years) referred for ablation of SVT were studied. Ablation was guided by 3D electroanatomic mapping in all but 2 procedures. A total of 41 SVT were diagnosed as intra-atrial reentrant tachycardia (n=30; cycle length, 310�68 ms), typical atrial flutter (n=4; cycle length, 288�42 ms), focal atrial tachycardia (n=6; cycle length, 400�60 ms), and atrial fibrillation (n=1). Ablation was successful in 73% of intra-atrial reentrant tachycardia, 75% of atrial flutter, and all focal atrial tachycardia and focal atrial fibrillation. During the follow-up period of 53�34 months, 2 patients were lost to follow-up, 3 died of heart failure, 2 underwent heart transplantation, and 1 underwent conduit replacement. Of the remaining group, 8 had sinus rhythm and 3 had SVT.

Conclusions—

Focal and reentrant mechanisms underlie postoperative SVT in patients with univentricular heart. Successive SVT developing over time may be caused by different mechanisms. Ablative therapy is potentially curative, with a procedural success rate of 78%. In patients who had multiple ablation procedures, the SVT originated from different atrial sites, suggesting that these new SVT were caused by progressive atrial disease. Despite recurrent SVT, sinus rhythm at the end of the follow-up period was achieved in 72%.
CACNA1C
Gene Polymorphisms, Cardiovascular Disease Outcomes, and Treatment Response
Authors: Beitelshees Amber L. , Navare Hrishikesh , Wang Danxin , Gong Yan , Wessel Jennifer , Moss James I. , Langaee Taimour Y. , Cooper-DeHoff Rhonda M. , Sadee Wolfgang , Pepine Carl J. , Schork Nicolas J. , Johnson Julie A.
Published: June 2009

Background—

The gene encoding the target of calcium channel blockers, the α1c-subunit of the L-type calcium channel (
CACNA1C
), has not been well characterized, and only small pharmacogenetic studies testing this gene have been published to date.

Methods and Results—

Resequencing of
CACNA1C
was performed followed by a nested case-control study of the INternational VErapamil SR/trandolapril STudy (INVEST) GENEtic Substudy (INVEST-GENES). Of 46 polymorphisms identified, 8 were assessed in the INVEST-GENES. Rs1051375 was found to have a significant interaction with treatment strategy (
P
=0.0001). Rs1051375 A/A genotype was associated with a 46% reduction in the primary outcome among those randomized to verapamil SR treatment, when compared with atenolol treatment (odds ratio 0.54 95% CI 0.32 to 0.92). In heterozygous A/G individuals, there was no difference in the occurrence of the primary outcome when randomized to verapamil SR versus atenolol treatment (odds ratio 1.47 95% CI 0.86 to 2.53), whereas homozygous G/G individuals had a greater than 4-fold increased risk of the primary outcome with verapamil treatment compared with those randomized to atenolol treatment (odds ratio 4.59 95% CI 1.67 to 12.67). We did not identify allelic expression imbalance or differences in mRNA expression in heart tissue by rs1051375 genotype.

Conclusions—

Variation in
CACNA1C
is associated with treatment response among hypertensive patients with stable coronary artery disease. Our data suggest a genetically defined group of patients that benefit most from calcium channel blocker therapy, a group that benefits most from β-blocker therapy, and a third group in which calcium channel blocker and β-blocker therapy are equivalent.
Comprehensive Desmosome Mutation Analysis in North Americans With Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy
Authors: den Haan A. Dénise , Tan Boon Yew , Zikusoka Michelle N. , Lladó Laura Ibañez , Jain Rahul , Daly Amy , Tichnell Crystal , James Cynthia , Amat-Alarcon Nuria , Abraham Theodore , Russell Stuart D. , Bluemke David A. , Calkins Hugh , Dalal Darshan , Judge Daniel P.
Published: June 2009

Background—

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited disorder typically caused by mutations in components of the cardiac desmosome. The prevalence and significance of desmosome mutations among patients with ARVD/C in North America have not been described previously. We report comprehensive desmosome genetic analysis for 100 North Americans with clinically confirmed or suspected ARVD/C.

Methods and Results—

In 82 individuals with ARVD/C and 18 people with suspected ARVD/C, DNA sequence analysis was performed on
PKP2, DSG2, DSP, DSC2
, and
JUP.
In those with ARVD/C, 52% harbored a desmosome mutation. A majority of these mutations occurred in
PKP2
. Notably, 3 of the individuals studied have a mutation in more than 1 gene. Patients with a desmosome mutation were more likely to have experienced ventricular tachycardia (73% versus 44%), and they presented at a younger age (33 versus 41 years) compared with those without a desmosome mutation. Men with ARVD/C were more likely than women to carry a desmosome mutation (63% versus 38%). A mutation was identified in 5 of 18 patients (28%) with suspected ARVD. In this smaller subgroup, there were no significant phenotypic differences identified between individuals with a desmosome mutation compared with those without a mutation.

Conclusions—

Our study shows that in 52% of North Americans with ARVD/C a mutation in one of the cardiac desmosome genes can be identified. Compared with those without a desmosome gene mutation, individuals with a desmosome gene mutation had earlier-onset ARVD/C and were more likely to have ventricular tachycardia.
The 4–5 December 2001 IMPROVE-2 Event: Observed Microphysics and Comparisons with the Weather Research and Forecasting Model
Authors: Lin Yanluan , Colle Brian A.
Published: June 2009

This paper highlights the observed and simulated microphysical evolution of a moderate orographic rainfall event over the central Oregon Cascade Range during 4–5 December 2001 of the Second Improvement of Microphysical Parameterization through Observational Verification Experiment (IMPROVE-2). Airborne in situ measurements illustrate the spatial variations in ice crystal distributions and amounts over the windward Cascades and within some convective cells. The in situ microphysical observations, ground radars, and surface observations are compared with four bulk microphysical parameterizations (BMPs) within the Weather Research and Forecasting (WRF) model. Those WRF BMP schemes that overpredict surface precipitation along the Cascade windward slopes are shown to have too rapid graupel (rimed snow) fallout. Most BMP schemes overpredict snow in the maximum snow depositional growth region aloft, which results in excessive precipitation spillover into the immediate lee of the Cascades. Meanwhile, there is underprediction to the east of the Cascades in all BMP schemes. Those BMPs that produce more graupel than snow generate nearly twice as much precipitation over the Oregon Coast Range as the other BMPs given the cellular convection in this region. Sensitivity runs suggest that the graupel accretion of snow generates too much graupel within select WRF BMPs. Those BMPs that generate more graupel than snow have shorter cloud residence times and larger removal of available water vapor. Snow depositional growth may be overestimated by 2 times within the BMPs when a capacitance for spherical particles is used rather than for snow aggregates. Snow mass–diameter relationships also have a large impact on the snow and cloud liquid water generation. The positive definite advection scheme for moisture and hydrometeors in the WRF reduces the surface precipitation by 20%–30% over the Coast Range and improves water conservation, especially where there are convective cells.
Fabrication of Hydroxyapatite-incorporated ZrO2-20 wt% Al2O 3 by Spark Plasma Sintering and Characterization
Authors: Shufeng Li  , Izui Hiroshi , Okano Michiharu , Weihua Zhang  , Watanabe Taku
Published: June 2009

Yttria-stabilized tetragonal zirconia/20 wt% alumina (TZP-3Y20A) composites were fabricated by spark plasma sintering at various sintering temperatures over the range of 1000—1400°C. Hydroxyapatite (HA) additive was added in volume fractions of 10—50% in order to increase the biocompatibility of the composite. The densification behavior of the TZP-3Y20A composite and that of the composites with HA were investigated. In the case of TZP-3Y20A composites, the density increases steadily with temperature and reaches a maximum value of 97.8% of the theoretical density at 1400°C. The solution interface formed between zirconia (ZrO2) and alumina (Al 2O3) strengthens the bond between ZrO2 and Al 2O3 grains and facilitates densification. In the case of TZP-3Y20A/HA composites, sintering at 1400°C led to the formation of tricalcium phosphate in the samples, which resulted from the decomposition of HA due to its limited thermal stability at high temperature; no reaction was observed between ZrO2 and HA. The addition of HA imposes a barrier effect on the diffusion between ZrO2 and Al2O3 grains, thus limiting the grain growth of ZrO2 and Al2O 3.
Preparation of Cu/Cr2O3 Composites by Mechanical Activation and In Situ Oxidation
Authors: Shuhua Liang  , Xianhui Wang  , Deming Kong  , Zhikang Fan
Published: June 2009

In order to improve the in situ oxidation kinetic condition of Al in Cu matrix, Cr, instead of Al was in situ oxidized to form Cu/Cr2O 3 composites in the present investigation, Cu-Cr powders with different solubilities after mechanical activation were utilized to synthesize Cu/Cr 2O3 composites, and their microstructure and stability were analyzed. The results show that although the Cu-Cr powders suffer from the same mechanical activation; Cr2O3 particles formed by the powders with different solubilities have great differences in size, amount, and distribution. In the range of experiments, the Cu/Cr2O 3 composite formed by Cu-Cr powders with 67% solution has large amounts of finer Cr2O3 particles uniformly distributed in Cu matrix and the best stability at elevated temperatures.
Integrating Sustainability into the Strategic Planning of National Tourism Organizations
Authors: Soteriou Evi C. , Coccossis Harris
Published: June 2009

This article describes an empirical study undertaken in national tourism organizations in Europe responsible for tourism planning to investigate the parameters that compose the capability to integrate sustainability into the strategic planning process and the factors that contribute to its development. Results indicate that both strategic planning and the integration of sustainability in national tourism organizations face problems that limit the potential of strategic planning to contribute substantially toward sustainability. Further to problems traced within the organizations and in the design of the strategic planning process, the research reveals the negative influence exerted by various exogenous factors. This article discusses the role that national tourism organizations can play in operationalizing sustainable tourism and pursuing it through strategic planning and suggests ways to improve performance in this respect. It also reveals a large scope for more empirical work for the integration of sustainability into strategic planning for tourism at a national level.
Effect of Moisture-induced Damage on Fracture Resistance of Rubber-modified HMA Mixtures
Authors: Othman Ayman M.
Published: June 2009

The impact of moisture-induced damage on the fracture resistance of rubber-modified hot mix asphalt (HMA) mixture as determined by the critical energy release rate (Jc) was investigated. Crumb rubber content of 15% by weight of binder was adapted. Semi-circular core specimens (76 mm radius and 57 mm thickness) were used for fracture resistance tests. An accelerated moisture damage program was established to evaluate the mixture resistance to moisture damage. Tested specimens were immersed in a water bath at a controlled temperature of 25°C under vacuum of 510 mm Hg at different moisture treatment periods of 0, 1, 2, and 7 days. A relationship between the moisture treatment period and the critical energy release rate was determined. The current investigation revealed a reduction on the fracture resistance and mechanical performance of the moisture treated mixtures. The reduction increased with the increase of moisture treatment period. The results also indicated significant improvement in mix stability, strength, and resistance to fracture and moisture damage when crumb rubber was applied to HMA mixtures.
Mechanical Testing and Characterization of a Swelling Elastomer
Authors: Qamar S.Z. , Al-Hiddabi S.A. , Pervez T. , Marketz F.
Published: June 2009

Elastomers are being increasingly used for sealing and other applications in the oil and gas industry. Specifically developed elastomers possess durable properties and have the ability to withstand detrimental effects of heat, chemicals, and harsh environments. For successful modeling and simulation of various downhole processes, it is very important to determine the behavior of elastomer materials under realistic well conditions. Of special interest is the class known as swelling elastomers. This article reports some results from experiments conducted on mechanical testing and characterization of an inert (nonswelling) and a water-swelling elastomer (both belonging to the EPDM family) used for sealing purposes by a local petroleum development firm. Experiments were designed and conducted in accordance with standard ASTM test methods. Apart from regularly available testing equipment, some simple test rigs and fixtures were designed and fabricated. Elastomer behavior was tested for hardness, compression set (at different temperatures and for different periods of time), tensile set (for different periods of time), tensile properties (fracture strength and percent elongation), and swelling. In the swelling test, different sample geometries (unconfined samples and samples mounted on steel plate) were tested for a total duration of 1000 h (roughly 45 days) in salt solutions of different concentrations and at different temperatures. Results show that compression set increases with increasing temperature and testing time, while room temperature tensile set also increases with longer testing time. Compared to the inert elastomer (exhibiting nonlinear elastic behavior like normal rubbers), swelling elastomer surprisingly showed linear stress—strain response. As expected, the inert elastomer did not exhibit any change in volume, while the swelling elastomer showed significant volume/thickness increase with increasing test temperature and decreasing salt concentration.
The neurosteroid dehydroepiandrosterone (DHEA) and its metabolites alter 5-HT neuronal activity via modulation of GABAAreceptors
Authors: Gartside SE , Griffith NC , Kaura V , Ingram CD
Published: June 2009

Dehydroepiandrosterone (DHEA) and its metabolites, DHEA-sulphate (DHEA-S) and androsterone, have neurosteroid activity. In this study, we examined whether DHEA, DHEA-S and androsterone, can influence serotonin (5-HT) neuronal firing activity via modulation of γ-aminobutryic acid (GABAA) receptors. The firing of presumed 5-HT neurones in a slice preparation containing rat dorsal raphe nucleus was inhibited by the GABAAreceptor agonists 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridinyl-3-ol (THIP) (25 μM) and GABA (100 μM). DHEA (100 and 300 μM) and DHEA-S (1, 10 and 100 μM) caused a rapid and reversible attenuation of the response to THIP. DHEA (100 μM) and DHEA-S (100 μM) also attenuated the effect of GABA. Androsterone (10 and 30 μM) markedly enhanced the inhibitory response to THIP (25 μM). The effect was apparent during androsterone administration but persisted and even increased in magnitude after drug wash-out. The data indicate that GABAAreceptor-mediated regulation of 5-HT neuronal firing is sensitive to negative modulation by DHEA and its metabolite DHEA-S is sensitive to positive modulation by the metabolite androsterone. The effects of these neurosteroids on GABAAreceptor-mediated regulation of 5-HT firing may underlie some of the reported behavioural and psychological effects of endogenous and exogenous DHEA.
Evaluation of a Cognitive Intervention Program for Juvenile Offenders
Authors: Bogestad Anna J. , Kettler Ryan J. , Hagan Michael P.
Published: June 2009

The purpose of this study is to evaluate a cognitive intervention program for juvenile offenders. Using the How I Think (HIT) Questionnaire, 165 offenders from three juvenile correctional facilities in Wisconsin are assessed after completion of the first two phases of the Juvenile Cognitive Intervention Program. Multiple t tests are used to assess change in thinking as measured by the HIT. Results indicate significant improvement in thinking across all areas as measured by the HIT. Discussion regarding the significance of the results and recommendations for future research are provided.
Do Older Adults Anticipate Relocating?
Authors: Stoeckel Kimberly J. , Porell Frank
Published: June 2009

The relationship between the occurrence of falls and the expectations older adults have about making future residential moves is examined in this research. Data from the 2002 Health and Retirement Study (HRS) are used to analyze self-reported probabilities of moving among a nationally representative sample of noninstitutionalized adults aged 65 and older. The results show that falls were predictive of anticipation of housing relocation as indicated by more than 50% reported probability of moving within the next 2 years. The results suggest that consideration of housing relocation is greater among older adults who experience tangible events indicative of a trajectory of deteriorating health.
Replication Evidence in Support of the Psychometric Properties of the Devereux Early Childhood Assessment
Authors: Jaberg Peter E. , Dixon David J. , Weis Glenna M.
Published: June 2009

The Devereux Early Childhood Assessment (DECA) was developed to assess the social-emotional functioning of preschool children. The developers of the DECA report initial validity and reliability evidence in support of the use of the instrument with 2- to 5-year-old children across the United States. There is further need to collect independent validity and reliability evidence in support of the use of the DECA for its intended uses. DECA data collected from the parents and teachers of 780 kindergarten students (age 5.0 to 5.11) from a rural Midwestern area of the United States were analyzed. The resulting internal consistency, interrater reliability, and factor structure estimates were generally consistent with what was reported by the DECA authors.
Assessing Teamwork and Collaboration in High School Students
Authors: Lijuan Wang  , MacCann Carolyn , Xiaohua Zhuang  , Liu Ou Lydia , Roberts Richard D.
Published: June 2009

Various policy papers assert that teamwork is an essential skill for the 21stcentury workforce. However, outside of organizational psychology research with adult populations, there are few reliable assessments of this construct with suitable validity evidence for test scores. To redress this issue, self-report, situational judgment, and teacher-report assessments of teamwork were developed for high school students. Various multivariate techniques were used to determine the structure of the scales, including factor and latent class analysis. Measures showed reasonable reliability and satisfactory validity evidence: Self-report, situational judgment, and teacher-report measures intercorrelated, and these measures also related to academic achievement. The advantages and disadvantages of each methodology are discussed, as are possible uses of this assessment system (e.g., evaluation of school-based programs that infuse curricula with modules on teamwork).
The Component Structure of Preliteracy Skills
Authors: Aouad Julie , Savage Robert
Published: June 2009

The simple view of reading (SVR) provides a conceptual framework for describing the processes involved when readers comprehend text. Strong evidence for the SVR comes from factor-analytic studies showing dissociations between decoding and comprehension skills. The aim of the present study is to investigate whether predecoding and comprehension components exist in Canadian English-speaking prereaders with the use of principal components analysis. All children ( N = 36) were administered a battery of prereading measures designed to assess predecoding skills and listening comprehension. Principal components analysis demonstrates that listening comprehension and predecoding measures loaded as distinct components. The findings provide support for the SVR framework and suggest that such structures do not simply reflect instruction. Implications for school psychologists working in early intervention are discussed.
Interprofessional Practice and Education in Health Care
Authors: Margison Judith A. , Shore Bruce M.
Published: June 2009

Calls for increased collaborative practices in school psychology parallel similar advances in the realm of health care. This article overviews the concepts associated with collaborative practice in school psychology and in health care (e.g., interaction, teamwork, and collaboration) and discusses how the literature emerging from interprofessional practice (IPP) and interprofessional education (IPE; jointly termed as IPPE) initiatives in health care may be beneficial to school psychology in general, and training programs in particular.
The Presence of Comorbidity in Tourette Syndrome Increases the Need for Pharmacological Treatment
Authors: Debes Nanette M. M. M. , Hjalgrim Helle , Skov Liselotte
Published: June 2009

Tourette syndrome is often accompanied by other syndromes, like attention-deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder, and its treatment is symptomatic. Because there are no European guidelines for pharmacological treatment in Tourette syndrome, we wanted to contribute to a better insight into the common practice in Scandinavia. Furthermore, we wanted to elaborate the influence of the presence of comorbidities and of the severity of tics on pharmacological treatment. We have examined the frequency, art, and reason for pharmacological treatment in a Danish clinical cohort of 314 children with Tourette syndrome. In total, 60.5% of the children once had received pharmacological treatment. Mostly, the treatment was started because of tics or ADHD. If ADHD or obsessive-compulsive disorder were present, more children received pharmacological treatment and more different agents were tried. The children who received pharmacological treatment had more severe tics than those without medication.
Acute Disseminated Encephalomyelitis with Bilateral Thalamic Necrosis
Authors: Dardiotis Efthimios , Kountra Persa , Kapsalaki Eftychia , Protogerou Georgia , Markopoulou Katerina
Published: June 2009

Acute disseminated encephalomyelitis is a monophasic inflammatory demyelinating disease of the central nervous system involving the white matter, and to a lesser extent, the gray matter. Bilateral thalamic lesions have been reported in 12% of pediatric patients with acute disseminated encephalomyelitis. In most cases, there is a benign clinical course and complete resolution of the lesions. Here, we describe a case in which acute disseminated encephalomyelitis is associated with severe neurological deficits and bilateral thalamic necrosis. Necrosis should be considered in cases of acute disseminated encephalomyelitis with persistent severe neurological deficits. Its presence is a poor prognostic indicator.
Features of a Subset of Children With Complex Partial Epilepsy Requiring Combination Therapy for Effective Seizure Control
Authors: Sloan Matthew E. , Simard-Tremblay Elisabeth , Shevell Michael I.
Published: June 2009

To identify children with complex partial seizures with increased risk for suboptimal seizure control with 1 medication, a computerized database containing all patients seen in the context of a single pediatric neurology practice was reviewed for patients with complex partial seizures. Participants included in analysis were then divided into groups; a group in whom seizure control was attained with a single medication (group 1) and a group for whom 2 or more medications were required for seizure control (group 2). Status epilepticus, developmental disabilities, and the presence of coexisting other seizures/types were also significantly different, with a higher predominance in group 2 children. Patients with status epilepticus, coexistent seizure types, and developmental disabilities should be identified and more carefully followed, with a lower threshold for starting these children on a combination of antiepileptic drugs adhered to.
Acquired Demyelinating Disorders of Childhood in the Western Cape, South Africa
Authors: Govender Rajeshree , Wieselthaler Nicky A. , Ndondo Alvin , Wilmshurst Jo M.
Published: June 2009

In a retrospective review of patients with acquired demyelinating disorders of the central nervous system, 19 children (0.6%) were identified from the Paediatric Neurology database of 3159 patients; 7 had acute disseminated encephalomyelitis, 1 had Schilder’s disease, 5 had multiple sclerosis, and 6 had acute transverse myelitis. The median age of presentation was 83 months, with increased incidence during the summer and winter months. The commonest presentation was hemiparesis. The commonest regions of magnetic resonance imaging (MRI) abnormalities were the deep white matter (68%) and cerebellum (48%).The patients with multiple sclerosis had more monosymptomatic presentations (P < .02), raised cerebrospinal fluid protein (P = .022), and contrast enhancement of lesions (P = .05) compared with the acute disseminated encephalomyelitis group. Neuroepidemiological published surveillances of African children provide no data about these disorders. The prevalence of acquired demyelinating disorders in resource-poor settings is under-estimated because of the large burden of infections and limited access to neuroimaging.