University of Nebraska Medical Center

Gene-gun Transfection of Hippocampal Neurons

Objective assessments of the physiological mechanisms that support speech are needed to monitor disease onset and progression in persons with ALS and to quantify treatment effects in clinical trials. In this video, we present a comprehensive, instrumentation-based protocol for quantifying speech motor performance in clinical populations.

Bioimaging methods used to assess cell biodistribution of nanoparticles are applicable for therapeutic and diagnostic monitoring of nanoformulated compounds. The methods described herein are sensitive and specific when assessed by histological coregistration. The methodologies provide a translational pathway from rodent to human applications.

Nanoparticles of indinavir, ritonavir, efavirenz and atazanavir were manufactured using wet milling, homogenization and ultrasonication. These nanoformulations, collectively termed nanoformulated antiretroviral therapy (nanoART), assessed macrophage-based drug delivery. Monocyte-derived macrophage nanoART uptake, retention and sustained release were determined. These preliminary studies suggest the potential of nanoART for clinical use.

This report provides a detailed description of the methodology and results of simultaneous endocardial and epicardial optical mapping of electrical excitation in the intact left atrium of a Langendorff-perfused sheep heart during stretch-induced atrial fibrillation.

Here, we present a protocol to fabricate electrospun nanofiber scaffolds with gradated organization of fibers and explore their applications in regulating cell morphology/orientation. Gradients with regard to physical and chemical properties of the nanofiber scaffolds offer a wide variety of applications in the biomedical field.

Islet β cell death precedes development of type 1 diabetes, and detecting this process may allow for early therapeutic intervention. Here, we provide a detailed description of how to measure differentially methylated INS DNA species in human serum as a biomarker of β cell death.

Here, we present a protocol for the isolation of whole, intact mouse mammary glands to investigate extracellular matrix (ECM) expression and ductal morphology. Mouse #4 abdominal glands were extracted from 8-10 week old female nulliparous mice, fixed in neutral buffered formalin, sectioned and stained using immunohistochemistry for ECM proteins.

The method presented here is designed to construct and validate an in vitro 3D model capable of measuring the force system generated by different archwires with V-bends placed between two brackets. Additional objectives are to compare this force system with different types of archwires and to previous models.

The synthesis of polyamine-based peptide amphiphiles (PPAs) is a significant challenge due to the presence of multiple amine nitrogens, which requires judicious use of protecting groups to mask these reactive functionalities. In this paper, we describe a facile method for the preparation of these new class of self-assembling molecules.

The overall goal of this article is to standardize the protocol for the isolation, characterization, and differentiation of cardiac stem cells (CSCs) from the adult mouse heart. Here, we describe a density gradient centrifugation method to isolate murine CSCs and elaborated methods for CSC culture, proliferation, and differentiation into cardiomyocytes.

This protocol provides a reliable method to establish humanized mice with both human immune system and liver cells. Dual reconstituted immunodeficient mice achieved via intrasplenic injection of human hepatocytes and CD34⁺ hematopoietic stem cells are susceptible to human immunodeficiency virus-1 infection and recapitulate liver damage as observed in HIV-infected patients.

Here, we present a protocol to characterize nucleosome particles at the single-molecule level using static and time-lapse atomic force microscopy (AFM) imaging techniques. The surface functionalization method described allows for the capture of the structure and dynamics of nucleosomes in high-resolution at the nanoscale.

This article demonstrates the technique of expanding a traditional, two-dimension (2D) electrospun nanofiber mat into a three-dimension (3D) scaffold through the depressurization of subcritical CO₂ fluid. These augmented scaffolds are 3D, closely mimic cellular nanotopographic cues, and preserve the functions of biologic molecules encapsulated within the nanofibers.

Here, we describe the use of a higher-throughput microfluidic bioreactor coupled with a fluorescent microscope for the analysis of shear stress effects on Pseudomonas aeruginosa biofilms expressing green fluorescent proteins, including instrument set up, the determination of biofilm coverage, growth rate, and morphological properties.

This article provides detailed methods for fabricating and characterizing a pneumatically actuating microfluidic device for chondrocyte compression.

In this protocol, lymphocytes are placed in the top chamber of a transmigration system, separated from the bottom chamber by a porous membrane. Chemokine is added to the bottom chamber, which induces active migration along a chemokine gradient. After 48 h, lymphocytes are counted in both chambers to quantitate transmigration.

Here, we present a protocol for simple isolation of specific groups of live neuronal cells expressing green fluorescent protein from transgenic Caenorhabditis elegans lines. This method enables a variety of ex vivo studies focused on specific neurons and has the capacity to isolate cells for further short-term culturing.

Here, we present a protocol to conjugate protein monomer by enzymes forming protein polymer with a controlled sequence and immobilize it on the surface for single-molecule force spectroscopy studies.

Described here is a protocol for renal denervation that is used to define the role of renal nerve-derived signaling in persistent renal tubular injury, inflammation, and fibrogenesis. It is focused on sympathetic nerve-mediated signaling.

Many rodent models of endometriosis are limited by technical complexity, reproducibility, and/or need for immunocompromised animals or special reporter mice. We present a simplified system of lesion induction using any experimental mouse with an independently verifiable, objective scoring system and with no requirement for ovariectomy or survival surgery.

Here we describe the RatWalker system, built by redesigning the MouseWalker apparatus to accommodate for the increased size and weight of rats. This system uses frustrated total internal reflection (FTIR), high-speed video capture, and open-access analysis software to track and quantify gait parameters.

The following article highlights various steps involved in initiating and maintaining veno-arterial extracorporeal membrane oxygenation in patients with cardiogenic shock.

Chronic pancreatitis (CP) is a disease characterized by inflammation and fibrosis of the pancreas, often associated with intractable abdominal pain. This article focuses on refining the technique to generate a mouse model of CP via bile duct infusion with 2,4,6 -trinitrobenzene sulfonic acid (TNBS).

Percutaneous ventricular assist devices are increasingly being utilized in patients with acute myocardial infarction and cardiogenic shock. Herein, we discuss the mechanism of action and hemodynamic effects of such devices. We also review algorithms and best practices for the implantation, management and weaning of these complex devices.

We describe the steps for the percutaneous implantation of the intra-aortic balloon pump (IABP), a mechanical circulatory support device. It acts by counterpulsation, inflating at the onset of diastole, augmenting diastolic aortic pressure and improving coronary blood flow and systemic perfusion, and deflating before systole, reducing left ventricular afterload.

The following article describes the stepwise procedure for placement of a device (e.g., Tandemheart) in cardiogenic shock (CS) that is a percutaneous left ventricular assist device (pLVAD) and a left atrial to femoral artery bypass (LAFAB) system that bypasses and supports the left ventricle (LV) in CS.

We describe a procedure to process computed tomography (CT) scans into high-fidelity, reclaimable, and low-cost procedural task trainers. The CT scan identification processes, export, segmentation, modeling, and 3D printing are all described, along with the issues and lessons learned in the process.

Here we present refined surgical procedures on successfully performing intraportal islet transplantation, a clinically relevant but technically challenging surgical procedure, in mice.

Presented here is a protocol for the implantation of a chronic cranial window for the longitudinal imaging of brain cells in awake, head-restrained mice.

The present protocol provides a detailed description of a percutaneous dual lumen right ventricular assist device and illustrates step-by-step instructions on the safe implanting, managing, and removing the device. Guidance on its use and troubleshooting complications from one of the most significant single-center experiences is also included.

Here, a protocol is presented for the efficient and accurate screening of tobacco genotypes for Phytophthora nicotianae resistance in seedlings. This is a practical approach for precision breeding, as well as molecular mechanism research.

This protocol describes a patterned direct contact glioma-astrocyte co-culture utilizing micro-contact printing on polyelectrolyte multilayers (PEMs) to pattern U87 or A172 GBM cells and primary astrocytes.

Visual, single-molecule biochemistry studied through microfluidic chambers is greatly facilitated using glass barrel, gas-tight syringes, stable connections of tubing to flow cells, and elimination of bubbles by placing switching valves between the syringes and tubing. The protocol describes dual optical traps that enable visualization of DNA transactions and intermolecular interactions.

Mechanical Circulatory Support For Cardiogenic Shock – Where Do We Stand?

This protocol describes a methodology to transfect Naegleria gruberi trophozoites with a construct that is maintained throughout passaging trophozoites in vitro, as well as through encystment and excystment.