Time scale theory on stability of explicit and implicit discrete epidemic models: applications to Swine flu outbreak.

Time scales theory has been in use since the 1980s with many applications. Only very recently, it has been used to describe within-host and between-hosts dynamics of infectious diseases. In this study, we present explicit and implicit discrete epidemic models motivated by the time scales modeling approach.

Continuous and discrete modeling of HIV-1 decline on therapy.

Mathematical models have shed light on the dynamics of HIV- 1 infection in vivo. In this paper, we generalize continuous mathematical models of drug therapy for HIV-1 by Perelson et al. (Science 271:1582-1586, 1996) and Perelson and Nelson (SIAM Rev 41:3-44, 1999) on time scales, i.

Parameter identification for gompertz and logistic dynamic equations.

In this paper, we generalize and compare Gompertz and Logistic dynamic equations in order to describe the growth patterns of bacteria and tumor. First of all, we introduce two types of Gompertz equations, where the first type 4-paramater and 3-parameter Gompertz curves do not include the logarithm of the number of individuals, and then we derive 4-parameter and 3-parameter Logistic equations. We notice that Logistic curves are better in modeling bacteria whereas the growth pattern of tumor is described better by Gompertz curves.

Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9): Impact of PCSK9 on Major Adverse Cardiac and Cerebrovascular Events.

Statins are the most widely prescribed drugs to reduce serum low density lipoprotein cholesterol (LDL-C) by inhibiting 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase. LDL-C reduction is associated with a decreased risk of atherosclerotic cardiovascular disease (ASCVD), including cardiovascular disease (CVD) and stroke. Statins reduce LDL-C by 30 to 40%, and the combination with other lipid-lowering agents such as ezetimibe leads to a further reduction by 20 to 25%.

[62-year old male patient with position-depending dyspnoe after hemipneumectomia].

Background: Dyspnoe is a symptom with a huge differential diagnostic spectrum. According to patients hemodynamic, acute forms can be caused by myocardial infarction, pulmonary embolism, pulmonary edema and heart rhythm disturbances while chronic forms can be caused by restrictive myocardial and pericardial diseases, hematooncological diseases, orthopedic deformations and chronic pulmonary diseases. The platypnea-orthodeoxia syndrome with underlying interatrial connection is a rare cause and need a special diagnostic work-up.

Use of a novel needle wire in patients undergoing transseptal puncture associated with severe septal tenting.

Introduction: An increasing number of patients undergo left atrial ablation procedures, since several approaches have proven efficacy in the treatment of atrial fibrillation. Although transseptal catheterization was generally shown be a safe technique, it harbors the principal risk of cardiac injury. Therefore, there is a need for a safe and effective tool to enable transseptal puncture in difficult cases as well.

Pulmonary vein isolation by duty-cycled bipolar and unipolar antrum ablation using a novel multielectrode ablation catheter system: first clinical results.

Background: The electrical disconnection of the pulmonary veins (PV) plays an important role in the ablation strategy of paroxysmal atrial fibrillation (PAF). Circumferential antral ablation with a conventional ablation technique using a steerable ablation catheter is sometimes difficult to perform and does not always result in isolation of the targeted PV.

Methods: Patients with symptomatic PAF were treated with a novel circular mapping/ablation catheter (PVAC).

Results of short-term and long-term pulmonary vein isolation for paroxysmal atrial fibrillation using duty-cycled bipolar and unipolar radiofrequency energy.

Background: Electrical disconnection of the pulmonary veins (PV) plays an important role in the ablation of paroxysmal atrial fibrillation (AF). Antral ablation using a conventional steerable ablation catheter often is technically challenging and time consuming.

Methods: Eighty-eight patients (mean age 58 +/- 11 years) with symptomatic paroxysmal AF underwent ablation with a circular mapping/ablation decapolar catheter (PVAC).

Renovascular hypertension by two-kidney one-clip enhances endothelial progenitor cell mobilization in a p47phox-dependent manner.

Background: Enhanced mechanical forces, e.g. in arterial hypertension, stimulate the formation of reactive oxygen species (ROS) by the NAD(P)H oxidase.

Mechanical stretch enhances mRNA expression and proenzyme release of matrix metalloproteinase-2 (MMP-2) via NAD(P)H oxidase-derived reactive oxygen species.

Mechanical stretch is a hallmark of arterial hypertension and leads to vessel wall remodeling, which involves matrix metalloproteinases (MMPs). Because mechanical stretch is further capable of inducing reactive oxygen species (ROS) formation via the NAD(P)H oxidase, we assessed whether mechanical stretch enhances MMP expression and activity in a NAD(P)H oxidase-dependent manner. Therefore, vascular smooth muscle cells (VSMCs) isolated from C57BL/6 mice were exposed to cyclic mechanical stretch.