Characterization and structural basis for the brightness of mCLIFY: a novel monomeric and circularly permuted bright yellow fluorescent protein.

We present mCLIFY: a monomeric, bright, yellow, and long-lived fluorescent protein (FP) created by circular permutation of YPet, the brightest yellow FP from for use in cellular and single molecule studies. mCLIFY retains the enhanced photophysical properties of YPET as a monomer at concentrations ≤ 40 μM. In contrast, we determined that YPet has a dimerization dissociation constant ( ) of 3.

Straightening Out the Elasticity of Myosin Cross-Bridges.

In a contracting muscle, myosin cross-bridges extending from thick filaments pull the interdigitating thin (actin-containing) filaments during cyclical ATP-driven interactions toward the center of the sarcomere, the structural unit of striated muscle. Cross-bridge attachments in the sarcomere have been reported to exhibit a similar stiffness under both positive and negative forces. However, in vitro measurements on filaments with a sparse complement of heads detected a decrease of the cross-bridge stiffness at negative forces attributed to the buckling of the subfragment 2 tail portion.

Whipple's endocarditis: a case report of a blood culture-negative endocarditis.

Background: Whipple's disease is caused by and causes a self-limiting gastrointestinal infection. The majority of the population is an asymptomatic carrier, however, in some patients, it causes an invasive infection with for example arthritis, endocarditis, or involvement of the eyes.

Case Summary: This case describes a man with long-lasting complaints of progressive dyspnoea caused by heart failure due to total destruction of the aortic and mitral valve as a result of endocarditis, diagnosed with serum polymerase chain reaction.

Effect of Using the HEART Score in Patients With Chest Pain in the Emergency Department: A Stepped-Wedge, Cluster Randomized Trial.

Background: The HEART (History, Electrocardiogram, Age, Risk factors, and initial Troponin) score is an easy-to-apply instrument to stratify patients with chest pain according to their short-term risk for major adverse cardiac events (MACEs), but its effect on daily practice is unknown.

Objective: To measure the effect of use of the HEART score on patient outcomes and use of health care resources.

Design: Stepped-wedge, cluster randomized trial.

No cardiac damage after endurance exercise in cardiologists cycling to the European Society of Cardiology meeting in Barcelona.

Aims: There are variable results reported for athletes and potential cardiac damage during exercise. In 2009 a group of cardiologists went by bicycle from the Netherlands to the European Society of Cardiology meeting in Barcelona and collected functional and biochemical parameters during this trip in order to evaluate whether cardiac damage was observed in a group of moderately trained amateur cyclists.

Methods And Results: All of the 20 amateur cyclists (17 men) completed the 1580 km in eight days with an average speed of 27.

Long-term comparison of sirolimus-eluting and bare-metal stents in ST-segment elevation myocardial infarction.

Objectives: We aimed to investigate, in patients with ST-segment elevation myocardial infarction (STEMI), whether the previously reported clinical benefits of sirolimus-eluting stent(s) (SES) in terms of reducing a major adverse cardiac and cerebrovascular event (MACCE) compared with bare-metal stent(s) (BMS) were maintained over a 5-year time period.

Background: In the prospective single-centre randomized DEBATER trial, SES significantly reduced the rate of MACCE in STEMI patients within 1 year compared with BMS, mainly driven by a reduction of target lesion revascularization. Randomized data on the long-term safety and efficacy of SES in STEMI patients are conflicting and limited.

Can postoperative mean transprosthetic pressure gradient predict survival after aortic valve replacement?

Background: In this study, we sought to determine the effect of the mean transprosthetic pressure gradient (TPG), measured at 6 weeks after aortic valve replacement (AVR) or AVR with coronary artery bypass grafting (CABG) on late all-cause mortality.

Methods: Between January 1998 and March 2012, 2,276 patients (mean age 68 ± 11 years) underwent TPG analysis at 6 weeks after AVR (n = 1,318) or AVR with CABG (n = 958) at a single institution. Mean TPG was 11.

Effect of a nurse-coordinated prevention programme on cardiovascular risk after an acute coronary syndrome: main results of the RESPONSE randomised trial.

Objective: To quantify the impact of a practical, hospital-based nurse-coordinated prevention programme on cardiovascular risk, integrated into the routine clinical care of patients discharged after an acute coronary syndrome, as compared with usual care only.

Design: RESPONSE (Randomised Evaluation of Secondary Prevention by Outpatient Nurse SpEcialists) was a randomised clinical trial.

Setting: Multicentre trial in secondary and tertiary healthcare settings.

Impact of prosthesis-patient mismatch on early and late mortality after aortic valve replacement.

Background: The influence of prosthesis-patient mismatch (PPM) on survival after aortic valve replacement (AVR) remains controversial. In this study, we sought to determine the effect of PPM on early (≤30 days) and late mortality (>30 days) after AVR or AVR combined with coronary artery bypass grafting (AVR with CABG).

Methods: Between January 1998 and March 2012, 2976 patients underwent AVR (n= 1718) or AVR with CABG (n=1258) at a single institution.

Tropheryma whipplei aortic valve endocarditis, cured without surgical treatment.

Background: Culture-negative endocarditis due to Tropheryma whipplei is a rare disease. Mostly the diagnosis is made by histologic examination of resected heart valve tissue.

Case Presentation: In this case report, we described a patient with a classical Whipple's disease.

Increased septum wall thickness in patients undergoing aortic valve replacement predicts worse late survival.

Background: Following guidelines, aortic valve replacement (AVR) in asymptomatic patients with severe aortic valve stenosis is often postponed until symptoms do occur. Delaying AVR will inevitably lead to progression of left ventricular hypertrophy. We studied the relationship between septum wall thickness indexed for body surface area (SWTI) as a measure for LV hypertrophy and 30-day and late all-cause mortality after AVR.

Comparison of drug-eluting and bare-metal stents for primary percutaneous coronary intervention with or without abciximab in ST-segment elevation myocardial infarction: DEBATER: the Eindhoven reperfusion study.

Objectives: The goal of this study was to demonstrate superiority of sirolimus-eluting stents (SES) over bare-metal stents (BMS) and of abciximab over no abciximab in primary percutaneous coronary intervention (PCI).

Background: Drug-eluting stents (DES) are increasingly used in primary PCI, but the recommendations for use in primary PCI are based on a few randomized controlled trials with selected patients. The usefulness of abciximab in primary PCI is not established.

Modeling of cortical bone adaptation in a rat ulna: effect of frequency.

We employ a recently developed model for the adaptation of cortical bone in response to mechanical loading to study the effect of loading frequency on the computed response, and we compare our results to previous experimental measurements on rat ulnae. We represent the cortical bone as a poroelastic material with orthotropic permeability. Bone adaptation in the model is related to a mechanical stimulus derived from the dissipation energy of the poroelastic flow induced by deformation.

Right atrial thrombus migrating to the superior vena cava during surgery.

Free-floating right heart thrombi are extremely mobile structures that carry a very high mortality rate. We describe a case of pulmonary embolism with a free-floating right heart thrombus that migrated to the superior vena cava during the institution of cardiopulmonary bypass.

Plasticity and dislocation dynamics in a phase field crystal model.

The critical dynamics of dislocation avalanches in plastic flow is examined using a phase field crystal model. In the model, dislocations are naturally created, without any ad hoc creation rules, by applying a shearing force to the perfectly periodic ground state. These dislocations diffuse, interact and annihilate with one another, forming avalanche events.

Emergence of foams from the breakdown of the phase field crystal model.

The phase field crystal (PFC) model captures the elastic and topological properties of crystals with a single scalar field at small undercooling. At large undercooling, new foamlike behavior emerges. We characterize this foam phase of the PFC equation and propose a modified PFC equation that may be used for the simulation of foam dynamics.

Numerical modeling of long bone adaptation due to mechanical loading: correlation with experiments.

The process of external bone adaptation in cortical bone is modeled mathematically using finite element (FE) stress analysis coupled with an evolution model, in which adaptation response is triggered by mechanical stimulus represented by strain energy density. The model is applied to experiments in which a rat ulna is subjected to cyclic loading, and the results demonstrate the ability of the model to predict the bone adaptation response. The FE mesh is generated from micro-computed tomography (microCT) images of the rat ulna, and the stress analysis is carried out using boundary and loading conditions on the rat ulna obtained from the experiments [Robling, A.

Molecular dynamics on diffusive time scales from the phase-field-crystal equation.

We extend the phase-field-crystal model to accommodate exact atomic configurations and vacancies by requiring the order parameter to be non-negative. The resulting theory dictates the number of atoms and describes the motion of each of them. By solving the dynamical equation of the model, which is a partial differential equation, we are essentially performing molecular dynamics simulations on diffusive time scales.

Effect of inorganic phosphate on the force and number of myosin cross-bridges during the isometric contraction of permeabilized muscle fibers from rabbit psoas.

The relation between the chemical and mechanical steps of the myosin-actin ATPase reaction that leads to generation of isometric force in fast skeletal muscle was investigated in demembranated fibers of rabbit psoas muscle by determining the effect of the concentration of inorganic phosphate (Pi) on the stiffness of the half-sarcomere (hs) during transient and steady-state conditions of the isometric contraction (temperature 12 degrees C, sarcomere length 2.5 mum). Changes in the hs strain were measured by imposing length steps or small 4 kHz oscillations on the fibers in control solution (without added Pi) and in solution with 3-20 mM added Pi.

Adaptive mesh computation of polycrystalline pattern formation using a renormalization-group reduction of the phase-field crystal model.

We implement an adaptive mesh algorithm for calculating the space and time dependence of the atomic density field in microscopic material processes. Our numerical approach uses the systematic renormalization-group formulation of a phase-field crystal model of a pure material to provide the underlying equations for the complex amplitude of the atomic density field--a quantity that is spatially uniform except near topological defects, grain boundaries, and other lattice imperfections. Our algorithm employs a hybrid formulation of the amplitude equations, combining Cartesian and polar decompositions of the complex amplitude.

Novel ultrasound contrast agent dilution method for the assessment of ventricular ejection fraction.

Aims: Left ventricular (LV) ejection fraction is an important determinant of prognosis in heart failure. We evaluated the accuracy of a novel algorithm for LV ejection fraction quantification based on indicator dilution curve (IDC) principles using ultrasound contrast as indicator, and compared the results with contrast enhanced biplane LV ejection fraction assessment. Method A diluted ultrasound contrast bolus (SonoVue) was injected intravenously in 31 patients (19 male, age 65 +/- 11) with known or suspected heart disease.

Cell partitioning during the directional solidification of trehalose solutions.

Previous studies have demonstrated that ice/cell interaction influences post thaw viability and specific cryoprotective agents can affect those interactions. Trehalose, a disaccharide, has been shown to have a protective benefit during conventional slow freezing. Existing theories have been put forth to explain the protective benefit of trehalose during desiccation and vitrification, but these theories do not explain the protective benefit observed during conventional freezing protocols.