Virtual patient model for evaluating automated inspired oxygen control.

Physiologic closed-loop control (PCLC) of inspired oxygen during mechanical ventilation involves frequent adjustment of inspired oxygen fraction (FO) based on feedback from monitoring peripheral oxygen saturation (SO). Safety assessments of PCLC algorithms are important prerequisites for patient care, but clinical trials often fail to represent worst-case scenarios that identify limits of safe usage and often do not quantify performance sensitivity to physiologic deviations. The objective of this study was to develop and validate a virtual patient model of pulmonary and systemic gas exchange to assess the safety and efficacy of a PCLC algorithm for FO control.

Surgical Ablation of Cardiac Tissue with Nanosecond Pulsed Electric Fields in Swine.

Background: Myocardial tissue can be ablated by the application nanosecond pulsed fields (nsPEFs). The applied electric fields irreversibly permeabilize cell membranes and thereby kill myocytes while leaving the extracellular matrix intact.

Methods: In domestic pigs (n = 10), hearts were exposed via sternotomy and either ablated in vivo ([Formula: see text] = 5) or in excised, Langendorff-perfused hearts ([Formula: see text] = 5).

Monopolar gene electrotransfer enhances plasmid DNA delivery to skin.

A novel monopolar electroporation system and methodologies were developed for in vivo electroporation intended for potential clinical applications such as gene therapy. We hypothesized that an asymmetric anode/cathode electrode applicator geometry could produce favorable electric fields for electroporation, without the typical drawback associated with traditional needle and parallel plate geometries. Three monopolar electrode applicator prototypes were built and tested for gene delivery of reporter genes to the skin in a guinea pig model.

Using Nanosecond Shocks for Cardiac Defibrillation.

The purpose of this review article is to summarize our current understanding of the efficacy and safety of cardiac defibrillation with nanosecond shocks. Experiments in isolated hearts, using optical mapping of the electrical activity, have demonstrated that nanosecond shocks can defibrillate with lower energies than conventional millisecond shocks. Single defibrillation strength nanosecond shocks do not cause obvious damage, but repeated stimulation leads to deterioration of the hearts.

Low-energy defibrillation with nanosecond electric shocks.

Aims: Reliable defibrillation with reduced energy deposition has long been the focus of defibrillation research. We studied the efficacy of single shocks of 300 ns duration in defibrillating rabbit hearts as well as the tissue damage they may cause.

Methods And Results: New Zealand white rabbit hearts were Langendorff-perfused and two planar electrodes were placed on either side of the heart.

Human placenta hydrogel reduces scarring in a rat model of cardiac ischemia and enhances cardiomyocyte and stem cell cultures.

Introduction: Xenogeneic extracellular matrix (ECM) hydrogels have shown promise in remediating cardiac ischemia damage in animal models, yet analogous human ECM hydrogels have not been well development. An original human placenta-derived hydrogel (hpECM) preparation was thus generated for assessment in cardiomyocyte cell culture and therapeutic cardiac injection applications.

Methods And Results: Hybrid orbitrap-quadrupole mass spectrometry and ELISAs showed hpECM to be rich in collagens, basement membrane proteins, and regenerative growth factors (e.

Experimental Assessment of Mouse Sociability Using an Automated Image Processing Approach.

Mouse is the preferred model organism for testing drugs designed to increase sociability. We present a method to quantify mouse sociability in which the test mouse is placed in a standardized apparatus and relevant behaviors are assessed in three different sessions (called session I, II, and III). The apparatus has three compartments (see Figure 1), the left and right compartments contain an inverted cup which can house a mouse (called "stimulus mouse").

Nanosecond pulsed platelet-rich plasma (nsPRP) improves mechanical and electrical cardiac function following myocardial reperfusion injury.

Ischemia and reperfusion (I/R) of the heart is associated with biochemical and ionic changes that result in cardiac contractile and electrical dysfunction. In rabbits, platelet-rich plasma activated using nanosecond pulsed electric fields (nsPRP) has been shown to improve left ventricular pumping. Here, we demonstrate that nsPRP causes a similar improvement in mouse left ventricular function.

Ablation of Myocardial Tissue With Nanosecond Pulsed Electric Fields.

Background: Ablation of cardiac tissue is an essential tool for the treatment of arrhythmias, particularly of atrial fibrillation, atrial flutter, and ventricular tachycardia. Current ablation technologies suffer from substantial recurrence rates, thermal side effects, and long procedure times. We demonstrate that ablation with nanosecond pulsed electric fields (nsPEFs) can potentially overcome these limitations.

Refraction of scroll-wave filaments at the boundary between two reaction-diffusion media.

We explore the shape and the dynamics of scroll-wave filaments in excitable media with an abruptly changing diffusion tensor, important for cardiac applications. We show that, similar to a beam of light, the filament refracts at the boundary separating domains with different diffusion. We derive the laws of filament refraction and test their validity in computational experiments.

IHC Profiler: an open source plugin for the quantitative evaluation and automated scoring of immunohistochemistry images of human tissue samples.

In anatomic pathology, immunohistochemistry (IHC) serves as a diagnostic and prognostic method for identification of disease markers in tissue samples that directly influences classification and grading the disease, influencing patient management. However, till today over most of the world, pathological analysis of tissue samples remained a time-consuming and subjective procedure, wherein the intensity of antibody staining is manually judged and thus scoring decision is directly influenced by visual bias. This instigated us to design a simple method of automated digital IHC image analysis algorithm for an unbiased, quantitative assessment of antibody staining intensity in tissue sections.

Quantitative immunohistochemical analysis reveals association between sodium iodide symporter and estrogen receptor expression in breast cancer.

Background: Human sodium iodide symporter (hNIS) gene over-expression is under active consideration worldwide as an alternative target molecule for breast cancer (BC) diagnosis and targeted radio-iodine treatment. However, the field demands better stratified analysis of endogenous hNIS expression across major BC subtypes. Therefore, we have analyzed subtype-specific variation of hNIS overexpression in breast tumor tissue samples by immunohistochemistry (IHC) and also report the development of a homogeneous, quantitative analysis method of digital IHC images.