Advanced Immunomodulatory Biomaterials for Therapeutic Applications.

The multifaceted biological defense system modulating complex immune responses against pathogens and foreign materials plays a critical role in tissue homeostasis and disease progression. Recently developed biomaterials that can specifically regulate immune responses, nanoparticles, graphene, and functional hydrogels have contributed to the advancement of tissue engineering as well as disease treatment. The interaction between innate and adaptive immunity, collectively determining immune responses, can be regulated by mechanobiological recognition and adaptation of immune cells to the extracellular microenvironment.

Electrodiagnostic Findings Using Radial Motor Segmental Conduction Study and Inching Test in Patients With Radial Neuropathy.

Objectives: The aims of this study were to characterize the electrodiagnostic findings of radial neuropathy using motor segmental conduction study and to determine the utility of subsequent inching test in precise lesion localization.

Design: Twenty-three patients with radial neuropathy were evaluated using radial neuropathy using motor segmental conduction study with three-point stimulation. The pathomechanism of the lesions according to the radial neuropathy using motor segmental conduction study was classified into three groups: conduction block, mixed lesion (combination of conduction block and axonal degeneration), and axonal degeneration.

Morphometric assessment of tibial nerve and its branches around the ankle.

It is essential to understand the considerable variations in bifurcation patterns of the tibial nerve (TN) and its peripheral nerves at the level of the tarsal tunnel to prevent iatrogenic nerve injury during surgical nerve release or nerve block. A total of 16 ankles of 8 human cadavers were dissected to investigate the branching patterns of the TN, using 2 imaginary lines passing through the tip of the medial malleolus (MM) as reference lines. Bifurcation patterns and detailed information on the relative locations of the medial plantar, lateral plantar, medial calcaneal, and inferior calcaneal nerves to the reference lines were recorded.

Biophysical interplay between extracellular matrix remodeling and hypoxia signaling in regulating cancer metastasis.

Mechanical properties of the tumor microenvironment play a critical role in cancer progression by activation of cancer mechano-responses. The biophysical interactions between cancer cells and their dynamic microenvironment are attributed to force-dependent alterations in molecular pathways that trigger the structural reorganization of intracellular organelles and their associated genetic modifications. Recent studies underscore the role of oxygen concentration in cancer metastasis.

Subcellular mechano-regulation of cell migration in confined extracellular microenvironment.

Cell migration is a highly coordinated cellular event that determines diverse physiological and pathological processes in which the continuous interaction of a migrating cell with neighboring cells or the extracellular matrix is regulated by the physical setting of the extracellular microenvironment. In confined spaces, cell migration occurs differently compared to unconfined open spaces owing to the additional forces that limit cell motility, which create a driving bias for cells to invade the confined space, resulting in a distinct cell motility process compared to what is expected in open spaces. Moreover, cells in confined environments can be subjected to elevated mechanical compression, which causes physical stimuli and activates the damage repair cycle in the cell, including the DNA in the nucleus.

Photonic control of ligand nanospacing in self-assembly regulates stem cell fate.

Extracellular matrix (ECM) undergoes dynamic inflation that dynamically changes ligand nanospacing but has not been explored. Here we utilize ECM-mimicking photocontrolled supramolecular ligand-tunable Azo self-assembly composed of azobenzene derivatives (Azo) stacked via cation-π interactions and stabilized with RGD ligand-bearing poly(acrylic acid). Near-infrared-upconverted-ultraviolet light induces -Azo-mediated inflation that suppresses cation-π interactions, thereby inflating liganded self-assembly.

Stretching of porous poly (l-lactide-co-ε-caprolactone) membranes regulates the differentiation of mesenchymal stem cells.

Among a variety of biomaterials supporting cell growth for therapeutic applications, poly (l-lactide-co-ε-caprolactone) (PLCL) has been considered as one of the most attractive scaffolds for tissue engineering owing to its superior mechanical strength, biocompatibility, and processibility. Although extensive studies have been conducted on the relationship between the microstructure of polymeric materials and their mechanical properties, the use of the fine-tuned morphology and mechanical strength of PLCL membranes in stem cell differentiation has not yet been studied. PLCL membranes were crystallized in a combination of diverse solvent-nonsolvent mixtures, including methanol (MeOH), isopropanol (IPA), chloroform (CF), and distilled water (DW), with different solvent polarities.

Selective Suppression of Integrin-Ligand Binding by Single Molecular Tension Probes Mediates Directional Cell Migration.

Cell migration interacting with continuously changing microenvironment, is one of the most essential cellular functions, participating in embryonic development, wound repair, immune response, and cancer metastasis. The migration process is finely tuned by integrin-mediated binding to ligand molecules. Although numerous biochemical pathways orchestrating cell adhesion and motility are identified, how subcellular forces between the cell and extracellular matrix regulate intracellular signaling for cell migration remains unclear.

Protective effect of alpha-lipoic acid and epalrestat on oxaliplatin-induced peripheral neuropathy in zebrafish.

Introduction/aims: Oxaliplatin is a platinum-based anti-cancer drug widely used in colorectal cancer patients, but it may cause peripheral neuropathy. As one of the main causes of oxaliplatin-induced peripheral neuropathy (OPN) is oxidative stress, which is also a key factor causing diabetic peripheral neuropathy (DPN), the aim of this study was to evaluate the preventive effects of alpha-lipoic acid (ALA) and epalrestat (EP), which are used for the treatment of DPN, in an OPN zebrafish model.

Methods: Tg(nbt:dsred) transgenic zebrafish, with sensory nerves in the peripheral lateral line, were treated with oxaliplatin, oxaliplatin/EP, and oxaliplatin/ALA for 4 days.

Micro-syringe chip-guided intratumoral administration of lipid nanoparticles for targeted anticancer therapy.

Background: Nano-sized drug delivery system has been widely studied as a potential technique to promote tumor-specific delivery of anticancer drugs due to its passive targeting property, but resulting in very restricted improvements in its systemic administration so far. There is a requirement for a different approach that dramatically increases the targeting efficiency of therapeutic agents at targeted tumor tissues.

Methods: To improve the tumor-specific accumulation of anticancer drugs and minimize their undesirable toxicity to normal tissues, a tumor-implantable micro-syringe chip (MSC) with a drug reservoir is fabricated.

Recent Studies and Progress in the Intratumoral Administration of Nano-Sized Drug Delivery Systems.

Over the last 30 years, diverse types of nano-sized drug delivery systems (nanoDDSs) have been intensively explored for cancer therapy, exploiting their passive tumor targetability with an enhanced permeability and retention effect. However, their systemic administration has aroused some unavoidable complications, including insufficient tumor-targeting efficiency, side effects due to their undesirable biodistribution, and carrier-associated toxicity. In this review, the recent studies and advancements in intratumoral nanoDDS administration are generally summarized.

Ultrasonographic Evaluation of the Optimal Needle Position in the Supinator Muscle.

Background And Purpose: Investigating the supinator muscle (SUP) is important for diagnosing radial neuropathy or cervical radiculopathy in needle electromyography (EMG). However, different authors have proposed several locations for needle EMG placement in the SUP. This study aimed to determine the optimal needle insertion position for examining the SUP via needle EMG under ultrasonographic guidance.

Clinical, Electrophysiological, and Sonographic Findings in Patients With Nerve Injury After Vessel Puncture.

Background And Purpose: This study aimed to describe the clinical, electrophysiological, and ultrasonographic findings of patients with nerve injury after vessel puncture.

Methods: Data on ten patients (three males and seven females) with nerve injury after vessel puncture were reviewed. Demographic and clinical data were analyzed retrospectively.

Botulinum Toxin Injection for the Treatment of Compression of Lateral Plantar Nerve by Flexor Digitorum Accessorius Longus.

The flexor digitorum accessorius longus is an anomalous muscle with a reported prevalence of 1.6%-12.2% in cadaveric studies.

Ultrasonographic features of ulnar nerve instability around the elbow in fresh cadavers.

Ultrasound (US) is commonly used to evaluate ulnar nerve instability (UNI) and snapping of the medial head of the triceps brachii muscle (ST). We aimed to determine the diagnostic accuracy of US in evaluating UNI, through cadaveric dissection, and to evaluate the US features and relationships of UNI and ST according to elbow flexion. Dynamic US was performed with elbow extension, 90° flexion, and full flexion positions on 18 elbows from 9 fresh cadavers.

A Proposed Safe Electromyographic Needle Insertion Technique for the Flexor Pollicis Longus Muscle Using Arterial Pulse Palpation: Preliminary Study with Ultrasonography.

Electromyographic needle access to the flexor pollicis longus (FPL) is challenging because of the risk of injuries to the superficial radial nerve (SRN) or radial artery (RA), which run close to the FPL. This study aimed to investigate the safe electromyographic needle insertion point of the FPL using a newly proposed RA pulse palpation method. Fifty forearms of 25 healthy individuals were studied.

Nuclear transport of STAT6 determines the matrix rigidity dependent M2 activation of macrophages.

Alternatively activated or M2 macrophages, as opposed to the well characterized pro-inflammatory or M1 macrophages, vitally regulate anti-inflammation, wound healing, and tissue repair to maintain tissue homeostasis. Although ubiquitous presence of macrophages in diverse tissues, exposed to different physical environments, infers distinct immune responses of M2 macrophages with high phenotypic heterogeneity, the underlying mechanism of how the varying extracellular mechanical conditions alter their immunological activation remains unclear. Here, we demonstrate that M2 activation requires a threshold mechanical cue from the extracellular microenvironment, and matrix rigidity-dependent macrophage spreading is mediated by the F-actin formation that is essential to regulate mechanosensitive M2 activation of macrophages.

Micropattern-based nerve guidance conduit with hundreds of microchannels and stem cell recruitment for nerve regeneration.

Guiding the regrowth of thousands of nerve fibers within a regeneration-friendly environment enhances the regeneration capacity in the case of peripheral nerve injury (PNI) and spinal cord injury (SCI). Although clinical treatments are available and several studies have been conducted, the development of nerve guidance conduits (NGCs) with desirable properties, including controllable size, hundreds of nerve bundle-sized microchannels, and host stem-cell recruitment, remains challenging. In this study, the micropattern-based fabrication method was combined with stem-cell recruitment factor (substance P, SP) immobilization onto the main material to produce a size-tunable NGC with hundreds of microchannels with stem-cell recruitment capability.

Injectable Hydrogel-Based Combination Cancer Immunotherapy for Overcoming Localized Therapeutic Efficacy.

Various immunotherapeutic agents that can elicit antitumor immune responses have recently been developed with the potential for improved efficacy in treating cancer. However, insufficient delivery efficiency at the tumor site, along with severe side effects after systemic administration of these anticancer agents, have hindered their therapeutic application in cancer immunotherapy. Hydrogels that can be directly injected into tumor sites have been developed to help modulate or elicit antitumor responses.

A Cadaveric Study of a Safe and Accurate Electromyographic Needle Approach to the Rhomboid Major.

Objective: This study aimed to investigate a safe and accurate electromyographic needle insertion site of the rhomboid major (RM) muscle using cadaver dissection.

Design: Dissection of the trapezius and rhomboid major muscles around the scapula was performed in 18 scapulae from nine fresh cadavers. The point (point A) at which the lateral margin of the lower trapezius muscle crossed the medial border of the scapula and the distal insertion point (point DI) of the rhomboid major muscle to the medial scapula were determined.

The role of cellular traction forces in deciphering nuclear mechanics.

Cellular forces exerted on the extracellular matrix (ECM) during adhesion and migration under physiological and pathological conditions regulate not only the overall cell morphology but also nuclear deformation. Nuclear deformation can alter gene expression, integrity of the nuclear envelope, nucleus-cytoskeletal connection, chromatin architecture, and, in some cases, DNA damage responses. Although nuclear deformation is caused by the transfer of forces from the ECM to the nucleus, the role of intracellular organelles in force transfer remains unclear and a challenging area of study.