The Influence of Topical Vasodilator-Induced Pharmacologic Delay on Cutaneous Flap Viability and Vascular Remodeling.

Background: Surgical delay is a well-described technique to improve survival of random and pedicled cutaneous flaps. The aim of this study was to test the topical agents minoxidil and iloprost as agents of pharmacologic delay to induce vascular remodeling and decrease overall flap necrosis as an alternative to surgical delay.

Methods: Seven groups were studied (n = 8 in each group), including the following: vehicle, iloprost, or minoxidil before treatment only; vehicle, iloprost, or minoxidil before and after treatment; and a standard surgical delay group as a positive control.

Induction of Neurogenesis and Angiogenesis in a Rat Hemisection Spinal Cord Injury Model With Combined Neural Stem Cell, Endothelial Progenitor Cell, and Biomimetic Hydrogel Matrix Therapy.

Unlabelled: Acute spinal cord injury is a devastating injury that may lead to loss of independent function. Stem-cell therapies have shown promise; however, a clinically efficacious stem-cell therapy has yet to be developed. Functionally, endothelial progenitor cells induce angiogenesis, and neural stem cells induce neurogenesis.

Hyaluronic acid based low viscosity hydrogel as a novel carrier for Convection Enhanced Delivery of CAR T cells.

Convection Enhanced Delivery (CED) infuses therapeutic agents directly into the intracranial area continuously under pressure. The convection improves the distribution of therapeutics such as those aimed at brain tumors. Although CED successfully delivers small therapeutic agents, this technique fails to effectively deliver cells largely due to cell sedimentation during delivery.

Stiffness of Protease Sensitive and Cell Adhesive PEG Hydrogels Promotes Neovascularization In Vivo.

Materials that support the assembly of new vasculature are critical for regenerative medicine. Controlling the scaffold's mechanical properties may help to optimize neovascularization within implanted biomaterials. However, reducing the stiffness of synthetic hydrogels usually requires decreasing polymer densities or increasing chain lengths, both of which accelerate degradation.

Encoding Hydrogel Mechanics via Network Cross-Linking Structure.

The effects of mechanical cues on cell behaviors in 3D remain difficult to characterize as the ability to tune hydrogel mechanics often requires changes in the polymer density, potentially altering the material's biochemical and physical characteristics. Additionally, with most PEG diacrylate (PEGDA) hydrogels, forming materials with compressive moduli less than ∼10 kPa has been virtually impossible. Here, we present a new method of controlling the mechanical properties of PEGDA hydrogels independent of polymer chain density through the incorporation of additional vinyl group moieties that interfere with the cross-linking of the network.

3D biofabrication strategies for tissue engineering and regenerative medicine.

Over the past several decades, there has been an ever-increasing demand for organ transplants. However, there is a severe shortage of donor organs, and as a result of the increasing demand, the gap between supply and demand continues to widen. A potential solution to this problem is to grow or fabricate organs using biomaterial scaffolds and a person's own cells.

Programming in situ immunofluorescence intensities through interchangeable reactions of dynamic DNA complexes.

The regulation of antibody reporting intensities is critical to various in situ fluorescence-imaging analyses. Although such control is often necessary to visualize sparse molecular targets, the ability to tune marker intensities is also essential for highly multiplexed imaging strategies in which marker reporting levels must be tuned both to optimize dynamic detection ranges and to minimize crosstalk between different signals. Existing chemical amplification approaches generally lack such control.

Configuring robust DNA strand displacement reactions for in situ molecular analyses.

The number of distinct biomolecules that can be visualized within individual cells and tissue sections via fluorescence microscopy is limited by the spectral overlap of the fluorescent dye molecules that are coupled permanently to their targets. This issue prohibits characterization of important functional relationships between different molecular pathway components in cells. Yet, recent improved understandings of DNA strand displacement reactions now provides opportunities to create programmable labeling and detection approaches that operate through controlled transient interactions between different dynamic DNA complexes.

Live-cell microarray surface coatings supporting reverse transduction by adeno-associated viruses.

High-throughput live-cell microarray technologies that facilitate combinatorial screening of genes and RNA interference (RNAi) would be invaluable in the identification of key gene expression profiles involved in complex cellular behaviors. Each spot on such a microarray can comprise a unique combination of genes or RNAi packaged into gene delivery vectors. Live target cells seeded on top of the microarrays would express the combination of genetic factors, potentially leading to phenotypic changes within cells.

Multiplexed and reiterative fluorescence labeling via DNA circuitry.

A class of reactive DNA circuits was adapted as erasable molecular imaging probes that allow fluorescent reporting complexes to be assembled and disassembled on a biological specimen. Circuit reactions are sequence-dependent and therefore facilitate multiplexed (multicolor) detection. Yet, the ability to disassemble reporting complexes also allows fluorophores to be removed and new circuit complexes to be used to label additional markers.

Design of DNA-conjugated polypeptide-based capture probes for the anchoring of proteins to DNA matrices.

A new method for protein surface functionalization was developed that utilizes DNA-conjugated artificial polypeptides to capture recombinant target proteins from the solution phase and direct their deposition onto DNA-functionalized matrices. Protein capture is accomplished through the coiled-coil association of an engineered pair of heterodimeric leucine zippers. Incorporating half of the zipper complex directly into the polypeptides and labeling these polymers with ssDNA enables the polypeptide conjugates to form intermediate linkages that connect the target proteins securely to DNA-functionalized supports.