bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coronary artery wall imaging in mice using osmium tetroxide and micro‐computed tomography (micro‐CT)
Authors: Pai Vinay M. , Kozlowski Megan , Donahue Danielle , Miller Elishiah , Xiao Xianghui , Chen Marcus Y. , Yu Zu‐Xi , Connelly Patricia , Jeffries Kenneth , Wen Han 
Published: February 2012

AbstractThe high spatial resolution of micro‐computed tomography (micro‐CT) is ideal for 3D imaging of coronary arteries in intact mouse heart specimens. Previously, micro‐CT of mouse heart specimens utilized intravascular contrast agents that hardened within the vessel lumen and allowed a vascular cast to be made. However, for mouse coronary artery disease models, it is highly desirable to image coronary artery walls and highlight plaques. For this purpose, we describe an ex vivo contrast‐enhanced micro‐CT imaging technique based on tissue staining with osmium tetroxide (OsO4) solution. As a tissue‐staining contrast agent, OsO4 is retained in the vessel wall and surrounding tissue during the fixation process and cleared from the vessel lumens. Its high X‐ray attenuation makes the artery wall visible in CT. Additionally, since OsO4 preferentially binds to lipids, it highlights lipid deposition in the artery wall. We performed micro‐CT of heart specimens of 5‐ to 25‐week‐old C57BL/6 wild‐type mice and 5‐ to 13‐week‐old apolipoprotein E knockout (apoE−/−) mice at 10 μm resolution. The results show that walls of coronary arteries as small as 45 μm in diameter are visible using a table‐top micro‐CT scanner. Similar image clarity was achieved with 1/2000th the scan time using a synchrotron CT scanner. In 13‐week‐old apoE mice, lipid‐rich plaques are visible in the aorta. Our study shows that the combination of OsO4 and micro‐CT permits the visualization of the coronary artery wall in intact mouse hearts.
Packing a pinch: functional implications of chela shapes in scorpions using finite element analysis
Authors: van der Meijden Arie , Kleinteich Thomas , Coelho Pedro 
Published: February 2012

AbstractScorpions depend on their pedipalps for prey capture, defense, mating and sensing their environment. Some species additionally use their pedipalps for burrowing or climbing. Because the pincers or chelae at the end of the pedipalps vary widely in shape, they have been used as part of a suite of characters to delimit ecomorphotypes. We here evaluate the influence of the different chela cuticular shapes on their performance under natural loading conditions. Chelae of 20 species, representing seven families and spanning most of the range of chela morphologies, were assigned to clusters based on chela shape parameters using hierarchical cluster analysis. Several clusters were identified corresponding approximately to described scorpion ecomorphotypes. Finite element models of the chela cuticulae were constructed from CT scans and loaded with estimated pinch forces based onin vivoforce measurements. Chela shape clusters differed significantly in mean Von Mises stress and strain energy. Normalized FEA showed that chela shape significantly influenced Von Mises stress and strain energy in the chela cuticula, with Von Mises stress varying up to an order of magnitude and strain energy up to two orders of magnitude. More elongate, high‐aspect ratio chela forms showed significantly higher mean stress compared with more robust low‐aspect ratio forms. This suggests that elongate chelae are at a higher risk of failure when operating near the maximum pinch force. Phylogenetic independent contrasts (PIC) were calculated based on a partly resolved phylogram with branch lengths based on an alignment of the 12S, 16S and CO1 mitochondrial genes. PIC showed that cuticular stress and strain in the chela were correlated with several shape parameters, such as aspect ratio, movable finger length, and chela height, independently of phylogenetic history. Our results indicate that slender chela morphologies may be less suitable for high‐force functions such as burrowing and defense. Further implications of these findings for the ecology and evolution of the different chela morphologies are discussed.
Mitochondrial basis of the anti‐arrhythmic action of lidocaine and modulation by the n‐6 to n‐3 PUFA ratio of cardiac phospholipids
Authors: Demaison Luc , Moreau Daniel , Clauw Fabienne , Vergely Catherine , Rochette Luc 
Published: February 2012

AbstractThe aim of this study was to evaluate the involvement of mitochondria in the mechanism of the anti‐arrhythmic lidocaine. Rats were fed with a diet containing either n‐6 polyunsaturated fatty acids (PUFAs, SSO group) or an equimolecular mixture of n‐3 and n‐6 PUFAs (FO group) for 8 weeks. The hearts were perfused according to the working mode using a medium with or without lidocaine 5 μm. They were then subjected to local ischemia (20 min) and reperfusion (30 min). Dietary n‐3 PUFAs triggered the expected decrease in the n‐6/n‐3 PUFA ratio of cardiac phospholipids. Reperfusing the ischemic area favored the incidence of severe arrhythmias. Lidocaine treatment abolished almost completely reperfusion arrhythmias in the FO group, but did not display anti‐arrhythmic properties in the SSO group. As it was indicated by measurements of the mitochondrial function, lidocaine seemed to favor mitochondrial calcium retention in the FO group, which might prevent cytosolic calcium spikes and reperfusion arrhythmias. In the SSO group, the resistance to lidocaine was associated with an aggravation of cellular damages. The mitochondrial calcium retention capacities were saturated, and lidocaine was unable to increase them, making the drug inefficient in preventing reperfusion arrhythmias.
Platelet transfusions: treatment options for hemorrhage secondary to thrombocytopenia
Authors: Hux Bryan D. , Martin Linda G. 
Published: February 2012

AbstractObjectiveTo review current human and veterinary protocols for platelet transfusion triggers, available platelet transfusion products to support veterinary thrombocytopenic patients, and the advantages and disadvantages of each product.Data SourcesData from human and veterinary literature.Human Data SynthesisProphylactic and therapeutic platelet transfusions are instrumental in managing human patients with thrombocytopenia. The platelet transfusion products used in human medicine consist of platelet concentrates, derived from pooled random donor platelets, or single‐donor apheresis platelets. Historically, platelet transfusions in human medicine have been prophylactic in nature; however, recent research suggests changing from a prophylactic transfusion strategy to a therapeutic transfusion strategy may be safe for most patients. The optimal platelet transfusion trigger and the use of prophylactic verses therapeutic platelet transfusions are ever changing in human medicine.Veterinary Data SynthesisThere have been many advances in platelet transfusion products, but fresh whole blood remains the most commonly used platelet transfusion product in veterinary medicine. New products such as lyophilized platelets and cryopreserved platelets offer the benefits of long shelf life, immediate availability, and higher concentration of platelets at smaller doses. Veterinary platelet transfusion guidelines are mostly extrapolated from human literature because data on veterinary platelet transfusions are lacking.ConclusionsIn veterinary medicine the most commonly available product for platelet transfusions is fresh whole blood, because of availability of blood donors and lack of a cost effective easily obtainable alternative. Cryopreserved and lyophilized platelets are promising new products being used in the treatment of hemorrhaging patients with thrombocytopenia. These products offer increased platelet concentrations at decreased volumes, longer storage shelf life, and decreased exposure to whole blood products. With the development of newer readily available products, platelet transfusion parameters, to include dose, platelet count trigger, presence of disease, and clinical signs, should be further evaluated in veterinary medicine.
Diagnosis and treatment of platelet hyperactivity in relation to thrombosis in dogs and cats
Authors: Wiinberg Bo , Jessen Lisbeth R. , Tarnow Inge , Kristensen Annemarie T. 
Published: February 2012

AbstractObjectiveTo review the mechanisms of platelet activation and options for diagnosing and treating platelet hyperactivity in relation to thrombosis in dogs and cats.Data SourcesProspective, retrospective, and review articles, as well as textbook chapters in both human and veterinary medicine. Articles were primarily, but not exclusively, retrieved viaMedline.Human Data SynthesisIn people, platelets are known to play a key role in the development of arterial thrombosis in numerous disease states and antiplatelet drugs are the cornerstone in the treatment of acute events and for prevention in patients at risk. For many years, aspirin was used as the sole antiplatelet drug in people, but the introduction of adenosine diphosphate receptor antagonists and integrin αIIbβ3inhibitors has significantly improved outcome in selective groups of patients.Veterinary Data SynthesisThe understanding of platelet activation in disease states has increased dramatically over the past decade. Simultaneously, a host of new methods for evaluating platelet function have been developed, which enable primarily researchers, but also clinicians to monitor the activity of platelets. Many of these methods have been validated for research purposes, but few have found their way to the clinics. Not a single correctly randomized clinical trial has been carried out with any antiplatelet drug for any indication in dogs or cats, and consequently, treatment is empiric and largely based on expert opinion or data from experimental studies.ConclusionsThe pathogenesis of thromboembolic disease is complex and multifactorial and the role of hyperactive platelets in this etiology remains to be clarified in most of the diseases associated with thrombosis in dogs and cats. Until efficacy data from well‐designed studies are available, antithrombotic therapy should consist of close monitoring, good supportive care, and judicious empirical use of antiplatelet agents.
The effect of hemodialysis ultrafiltration on changes in whole blood viscosity
Authors: Shirazian Shayan , Rios‐Rojas Liliana , Drakakis James , Dikkala Sudharani , Dutka Paula , Duey Marc , Cho Daniel J. , Fishbane Steven 
Published: February 2012

AbstractIncreased whole blood viscosity (WBV) can be injurious to the vascular endothelium and increase the risk of atherothrombotic events. This study examined the effect of hemodialysis ultrafiltration (UF) on WBV, with a focus on high vs. low‐volume UF patients. In stable hemodialysis patients, blood was drawn for hematocrit (Hct) and WBV at the start, midpoint, and at the end of dialysis. For analysis, patients were divided into high UF (≥2700 mL) or low UF (<2700 mL) groups. A total of 59 patients completed the study. Mean Hct increased during dialysis in both groups. The intradialytic increase in Hct was significantly greater in the high vs. the low UF group (3.2% vs. 1.28%, P = 0.01), with a significantly higher end‐dialysis Hct in the high UF group (40.5% vs. 38%, P = 0.02). At the end of dialysis, both high shear rate WBV (P < 0.01) and low shear rate WBV (P < 0.01) were significantly higher in the high UF compared with the low UF group. There was an approximately two‐fold greater increase in high shear rate (P < 0.01) and low shear rate (P = 0.01) WBV during dialysis in high vs. low UF groups. The increase in high shear rate WBV during dialysis was significantly correlated with an increase in Hct (R2 = 0.63, P < 0.01). We found that hemodialysis UF causes a surge in WBV. The surge was of greater magnitude in high than in low UF patients.
Dilator venotomy technique for placement of hemodialysis catheter following recanalization of occluded central vein
Authors: Pua Uei 
Published: February 2012

AbstractRecanalization of occluded central veins for insertion of hemodialysis catheter is a particular attractive option in patients who are catheter dependent for hemodialysis, as it delays exhaustion of conventional venous accesses. Literature detailing techniques for catheter placement in recanalized veins remain sparse. We hereby describe a safe and economical technique of using dilator venotomy to allow catheter placement following successful recanalization.
In‐vitro Degradation and Bioactivity of Tailored Amorphous Multi Porous Scaffold Structure
Authors: Zhang Di , Jain Himanshu , Hupa Mikko , Hupa Leena 
Published: February 2012

A key requirement for the use of bio scaffold is that its degradation rate matches the growth rate of target tissue. Therefore, the degradation of recently developed tailored amorphous multiporous (TAMP) scaffold of 70SiO2·30CaO (mol%) in simulated body fluid (SBF) was studied under both static and quasi‐dynamic conditions. The degradation was assessed through the dissolution of silica from the glass into SBF, while the in‐vitro bioactivity was characterized by precipitation of calcium phosphate (CaP) on and inside the scaffold. Under static conditions, the degradation stopped due to the saturation of solution with silica in 3 days, whereas the precipitation of CaP continued. Rapid degradation and better in‐vitro bioactivity was found under quasi‐dynamic conditions, where the concentration gradient across the sample was maintained. The degradation followed exponential dependence on time with a half‐life of 15.4 days and initial degradation rate 4.5% day−1. The remaining samples maintained their integrity and pore structure during degradation. The degradation occurred in three distinct stages: (a) wetting stage, (b) initial degradation stage when CaP precipitation dominates, and (c) intensive degradation stage when the nanopores rupture and network dissolves. By varying the sintering parameters the nanopore structure, and hence the degradation rate, can be tailored to suit the anticipated tissue regeneration rate. With demonstrated rapid and controllable degradation and good in‐vitro bioactivity, the TAMP scaffold shows promise as candidate for bone regeneration application under various conditions in the body.
Factors shaping the development of working time regulation in the United States and Europe
Authors: Dembe Allard E. 
Published: February 2012

Abstract.In nineteenth century Britain, the first working time regulations were prompted by humanitarian concerns about women and children employed in factories. In the United States, working time laws were initially introduced in response to union activism and labour unrest. During the twentieth century, policy‐makers enacted statutes that shortened hours of work in an attempt to spread available work and thereby curb unemployment. The past 20 years, with the adoption of the European Working Time Directive, have reflected a movement towards social and political integration, continuing political pressure to curb unemployment, and growing acceptance of ergonomics and work organization as components of international safety regulation.
IDH Mutation Detection in Formalin‐Fixed Paraffin‐Embedded Gliomas Using Multiplex PCR and Single‐Base Extension
Authors: Perizzolo Marco , Winkfein Bob , Hui Susan , Krulicki Wally , Chan Jennifer A. , Demetrick Douglas J. 
Published: February 2012

AbstractIsocitrate dehydrogenase (IDH) genes are mutated in a significant portion of gliomas, myeloid leukemias and chondroid neoplasms. In gliomas, IDH mutations are prognostic, as those tumors with the mutation are associated with a proneural subclass and have longer survival compared with those without the mutation. We developed a simple, PCR‐based SNaPshot® assay (Life Technologies, Carlsbad, CA, USA) to detect IDH1/2 mutations. This protocol combines a single, multiplexed PCR reaction using gene specific primers followed by a single, multiplexed SNaPshot reaction and detection by capillary electrophoresis. In a blinded study of 32 paraffin‐embedded glioma specimens previously screened for IDH mutations by a PCR/direct sequencing method, concordance of our IDH SNaPshot test with sequencing was 100%. We performed the assay on an additional 57 specimens submitted for diagnostic IDH mutation evaluation. Data analysis was much faster and easier to perform than analysis of the sequencing data, and results could be obtained in 1 day from DNA extraction to analysis. Furthermore, we could readily identify a mixture of 5% mutant allele vs. 95% wild‐type allele in our SNaPshot assay, in comparison to approximately 20% mutant allele in our PCR‐sequencing assay. Our assay represents a fast, sensitive, straightforward method of reliably detecting common mutations of IDH genes in glial neoplasms, or other tumors.
Evaluation of the Vietnamese A6 mortality reporting system: injury as a cause of death
Authors: Stevenson Mark R , Ngoan Le Tran , Hung Dang Viet , Huong Tu Nguyen Thi , Mai Anh Luong , Ivers Rebecca Q , Huong Hoang Thanh 
Published: February 2012

BackgroundDespite the fact that the A6 mortality reporting system has been operating for almost 20 years in Vietnam, there has been no systematic evaluation of the system. This study assesses the completeness, sensitivity and positive predictive value of the system in relation to injury related mortality.MethodsEvaluation of the A6 system was undertaken in three (geographically distributed) provinces in Vietnam. Deaths identified in the A6 system were compared with deaths identified by an independent consensus panel to determine the per cent completeness of the A6 system. Verbal autopsies (VA) were conducted for all identified deaths from the consensus panels, and the sensitivity and positive predictive value of the A6 system were assessed using the VAs as the reference.Results5273 deaths were identified from the A6 system with a further 340 cases identified by the independent consensus panel (total n=5613). Injury related deaths accounted for 13.6% (n=763) of all deaths with an overall injury mortality rate of 55.3 per 100 000 person years. The per cent completeness of the A6 system in relation to injury deaths was 93.9% with a sensitivity of 75.4%, specificity of 98.4% and positive predictive value of 88.4%.ConclusionsThe A6 mortality reporting system is embedded within the commune health system and is the lead mortality reporting system for the Ministry of Health. The system performs well in relation to its completeness and classification of injury related deaths. With further enhancements and ongoing support from government and donor agencies, the A6 system will be a valuable resource for identifying and planning preventive strategies targeting the leading causes of injury related deaths in Vietnam.
Long-Term Mortality After Transvenous Lead Extraction
Authors: Maytin Melanie , Jones Samuel O. , Epstein Laurence M. 
Published: February 2012

Background—
The number of cardiovascular implantable electronic devices has increased progressively and has led to an increased need for transvenous lead extraction (TLE). Multiple reports of TLE procedural outcomes exist; however, data regarding postprocedural and long-term mortality are limited.

Methods and Results—

We performed a retrospective study of consecutive patients undergoing TLE at a single, high-volume center. Patient characteristics, indications, and outcomes were analyzed. A multivariable Cox regression model was developed to identify factors associated with mortality. Between January 2000 and December 2010, 985 patients underwent 1043 TLE procedures. The cohort was 68% male, with a mean age of 63 years (range, 15–95 years) and a left ventricular ejection fraction of 40±17%. Indications included systemic infection (18%), pocket infection (32%), lead malfunction (30%), and other (device upgrade, venous occlusion, and advisory leads; 20%). There were no procedure-related deaths. The mean follow-up was 3.7 years (range, 0.1–11.3 years). Kaplan–Meier analysis demonstrated a cumulative mortality of 2.1% at 30 days, 4.2% at 3 months, 8.4% at 1 year, and 46.8% at 10 years. In multivariable analysis, systemic infection (hazard ratio [HR], 3.52; 95% CI, 1.95–6.38;
P
<0.0001), local infection (HR, 2.70; 95% CI, 1.55–4.67;
P
=0.0004), device system upgrade (HR, 2.14; 95% CI, 1.07–4.25;
P
=0.03; indication compared with a reference group of extraction for lead malfunction), diabetes mellitus (HR, 1.71; 95% CI, 1.25–2.35;
P
=0.0009), increasing age (HR, 1.05; 95% CI, 1.04–1.07;
P
<0.0001), and serum creatinine (HR, 1.16; 95% CI, 1.01–1.35;
P
=0.04) were significant correlates of increased mortality risk.

Conclusions—
Although TLE procedural mortality is exceedingly low at high-volume centers, postprocedural and long-term mortality remain high in certain patient populations, such as elderly patients and those undergoing TLE for infectious indications and device system upgrade. Information regarding TLE long-term outcomes may help guide cardiovascular implantable electronic device and lead management.
Presence of Atrial Fibrillation Is Independently Associated With Adverse Outcomes in Patients Hospitalized With Heart Failure
Authors: Mountantonakis Stavros E. , Grau-Sepulveda Maria V. , Bhatt Deepak L. , Hernandez Adrian F. , Peterson Eric D. , Fonarow Gregg C. 
Published: February 2012

Background—
It is unclear if the presence of atrial fibrillation (AF) on admission is associated with worse in-hospital outcomes in patients hospitalized with heart failure (HF). This study evaluated the clinical characteristics, management, length of stay, and mortality of HF patients with and without AF.

Methods and Results—

We studied 99 810 patients from 255 sites admitted with HF enrolled in Get With The Guidelines–Heart Failure between January 1, 2005, and December 31, 2010. Patients with AF on admission were compared with patients in sinus rhythm. A total of 31 355 (31.4%) HF patients presented with AF, of which 6701 (21.3%) were newly diagnosed. Patients in AF were older (77±12 versus 70±15,
P
<0.001) and were more likely to have history of stroke and valvular heart disease. AF patients had higher B-type natriuretic peptide levels and ejection fraction (42±17% versus 39±17%,
P
<0.001). AF patients were more likely to be hospitalized >4 days (48.8% versus 41.5%,
P
<0.001), discharged to a facility other than home (28.5% versus 19.7%,
P
<0.001), and had higher hospital mortality rate (4.0% versus 2.6%,
P
<0.001). AF, particularly newly diagnosed, was independently associated with adverse outcomes (adjusted odds ratios and 95% confidence intervals for mortality 1.17, 1.05–1.29,
P
=0.0029, and 1.29, 1.10–1.52,
P
=0.0023 for AF and newly diagnosed AF, respectively).

Conclusions—
In patients hospitalized with HF, AF is present in one-third and is independently associated with adverse hospital outcomes and longer length of stay. Whether prompt restoration of sinus rhythm would improve outcomes in patients hospitalized with HF and new-onset or paroxysmal AF is unclear and requires further study.