Publications by authors named "Hugh Xiao"

Advancing cardiac tissue engineering requires innovative fabrication techniques, including 3D bioprinting and tissue maturation, to enable the generation of new muscle for repairing or replacing damaged heart tissue. Recent advances in tissue engineering have highlighted the need for rapid, high-resolution bioprinting methods that preserve cell viability and maintain structural fidelity. Traditional collagen-based bioinks gel slowly, limiting their use in bioprinting.

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Engineering functional cellular tissue components holds great promise in regenerative medicine. Collagen I, a key scaffolding material in bodily tissues, presents challenges in controlling its assembly kinetics in a biocompatible manner in vitro, restricting its use as a primary scaffold or adhesive in cellular biofabrication. Here we report a collagen fabrication method termed as tunable rapid assembly of collagenous elements that leverages macromolecular crowding to achieve the instant assembly of unmodified collagen.

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The extracellular matrix (ECM) is the body's natural cell-scaffolding material, and its structure and content are often imitated for applications in tissue engineering and regenerative medicine to promote biocompatibility. One approach toward biomimicking natural ECMs is to utilize decellularized extracellular matrices (dECMs), which involve removing cellular components from native tissues to preserve natural components. Solubilizing dECMs to produce bioinks therefore holds high potential for 3D biofabrication and bioprinting of bioactive scaffolds and tissues.

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Fluid viscosity and osmolarity are among some of the underappreciated mechanical stimuli that cells can detect. Abnormal changes of multiple fluidic factors such as viscosity and osmolarity have been linked with diseases such as cystic fibrosis, cancer, and coronary heart disease. Changes in viscosity have been recently suggested as a regulator of cell locomotion.

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Damage and repair are recurring processes in tissues, with fibroblasts playing key roles by remodeling extracellular matrices (ECM) through protein synthesis, proteolysis, and cell contractility. Dysregulation of fibroblasts can lead to fibrosis and tissue damage, as seen in idiopathic pulmonary fibrosis (IPF). In advanced IPF, tissue damage manifests as honeycombing, or voids in the lungs.

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Controllable assembly of cells and tissues offers potential for advancing disease and development modeling and regenerative medicine. The body's natural scaffolding material is the extracellular matrix, composed largely of collagen I. However, challenges in precisely controlling collagen assembly limit collagen's applicability as a primary bioink or glue for biofabrication.

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Complex motions of immune cells are an integral part of diapedesis, chemotaxis, phagocytosis, and other vital processes. To better understand how immune cells execute such motions, we present a detailed analysis of phagocytic spreading of human neutrophils on flat surfaces functionalized with different densities of immunoglobulin G (IgG) antibodies. We visualize the cell-substrate contact region at high resolution and without labels using reflection interference contrast microscopy and quantify how the area, shape, and position of the contact region evolves over time.

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Drug treatment against liver cancer has limited efficacy due to heterogeneous response among liver cancer subtypes. In addition, the functional biophysical phenotypes which arise from this heterogeneity and contribute to aggressive invasive behavior remain poorly understood. This study interrogated how heterogeneity in liver cancer subtypes contributes to differences in invasive phenotypes and drug response.

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Cellular interactions with the extracellular matrix (ECM) play a key role in modulating biological processes. While studies have identified key molecular factors of these interactions, the mechanical regulation associated with these interactions is not well characterized. To address this, we present an image analysis platform to analyze time-dependent dynamics observed in lung fibroblasts embedded in a 3D collagen matrix.

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Nanomaterials (NMs) have revolutionized multiple aspects of medicine by enabling novel sensing, diagnostic, and therapeutic approaches. Advancements in processing and fabrication have also allowed significant expansion in the applications of the major classes of NMs based on polymer, metal/metal oxide, carbon, liposome, or multi-scale macro-nano bulk materials. Concomitantly, concerns regarding the nanotoxicity and overall biocompatibility of NMs have been raised.

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Bortezomib, a proteasome inhibitor with efficacy in multiple myeloma, is associated with thrombocytopenia, the cause and kinetics of which are different from those of standard cytotoxic agents. We assessed the frequency, kinetics, and mechanism of thrombocytopenia following treatment with bortezomib 1.3 mg/m2 in 228 patients with relapsed and/or refractory myeloma in 2 phase 2 trials.

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Bortezomib, a potent and reversible proteasome inhibitor, affects the myeloma cell and its microenvironment, resulting in down-regulation of growth and survival signaling pathways and durable responses in patients with relapsed and refractory myeloma. Potential associations between baseline parameters and outcomes with bortezomib were explored in 202 patients who received bortezomib 1.3 mg/m2 twice weekly for 2 weeks every 3 weeks for up to 8 cycles in a phase 2 trial.

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