Chang-Moon Lee

The morphology and micromorphology of Aristotle’s lantern, the feeding apparatus of Scaphechinus mirabilis, were examined using light microscopy, scanning electron microscopy, and X-ray microscopy. S. mirabilis had food grooves on the ventral side, which extended to the mouth. Aristotle’s lantern was a star-shaped calcareous skeletal structure attached to the test by the apophysis and consisted of pyramids, joints, and teeth. The pyramid consisted of two demi-pyramids, an epiphysis, and a bump, whereas the joint located between the pyramids consisted of the interpyramidal ligament and rotula. The tooth was an elongated trapezoid with one pointed end (3.98 × 0.97 × 0.38 mm) and was divided into an embedded part and a projection part. The embedded part was connected to the dental ligament and dental promoter muscle, whereas the projection part was divided into a basal projection part covered by the peridental membrane and an apical projection part protruding beyond the tooth slide. The tooth exhibited a calcareous lamellar structure composed of 15–20 layers, and its distal end was worn. These findings indicate that the morphology of the tooth is specialized for internal crushing of sediment and food particles within the Aristotle’s lantern.

This study addresses the limitations of synthetic hair dyes, such as potential carcinogenicity and allergies, and the drawbacks of conventional natural dyes, like long treatment times. The research proposes a safe and efficient hair dyeing system using dopamine (DA) and genipin (GP). When applied together, DA and GP undergo rapid self-assembly and cross-linking to coat hair, turning it black within 40 min. The dyeing speed and color intensity can be controlled by adjusting the GP concentration. Evaluations using SEM, UV–Vis, and ATR–FTIR spectroscopy confirmed effective morphological changes, while MTT assays demonstrated low toxicity. Furthermore, the dyed hair exhibited high durability, maintaining its color even after dozens of shampooing cycles. This DA/GP dye system provides a promising natural alternative for rapid, safe, and long-lasting hair coloring.

Owing to the growing aging population in developed countries, permanent hair dyes have gained significant attention in the cosmetic industry for the coverage of gray hair. However, synthetic hair dyes have side effects such as carcinogenesis and allergies. To mitigate these side effects, attempts have been made to replace synthetic dyes with natural dyes. Despite their advantages, natural dyes have limitations, such as dull color, limited durability, prolonged dyeing time, and the need for heavy-metal mordants. Therefore, this study aimed to improve hair dyeing speed, enhance dye durability, and reduce dye toxicity by employing natural materials such as dopamine (DA) and genipin (GP). The color reaction and morphological changes of hair dyed with DA and GP were investigated using colorimetric measurements, scanning electron microscopy, UV–Vis spectroscopy, and ATR–FTIR spectroscopy. Furthermore, a crystal violet assay was performed to assess in vitro toxicity. When DA and GP were applied to hair, they rapidly coated the hair through self-assembly and cross-linking, turning it black within 10 min. The time required for the hair to become black was controlled by adjusting the amount of GP in the presence of DA. Hair dyed with DA and GP maintained the dyed color even after several dozen shampooing cycles. These results demonstrate that the DA/GP dye system addresses the side effects associated with synthetic hair dyes and provides a positive effect.

Background/Objectives: Osteoporosis is caused by excessive osteoclast activation via the receptor activator nuclear factor kappa B ligand (RANKL), which is released from osteoblasts or osteocytes. RANKL regulates osteoclast activity by binding to the receptor activator of nuclear factor kappa B (RANK) in the canonical pathway or leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) in the non-canonical pathway. In this study, we attempted to develop an intact small-fragment protein based on RANKL by removing the RANK-binding site and transforming the amino acid residues at crucial sites to inhibit osteoclast activity and treat osteoporosis. Methods: We expressed a small-fragment variant of RANKL as a soluble glutathione S-transferase (GST) or 6x histidine (His)-tagged fusion protein using a GST- or His-binding domain tag expression vector system. To generate an intact form of small-fragment RANKL, ribosome-inactivating protein–His-fusion RANKL was purified using HisTrap affinity chromatography and treated with tobacco etch virus nuclear inclusion endopeptidase to remove the His-tag fusion protein. Tartrate-resistant acid phosphatase (TRAP) and bone resorption pit formation assays were performed to analyze the inhibitory effects on osteoclast differentiation and activation. Results: The intact forms of 225RANKL295P and 225RANKL295A showed the strongest inhibitory effects on TRAP activity and bone resorption pit formation. Conclusions: Using an optimal construct design, a large and diverse range of small RANKL fragments could be generated. This suggests that the generation of small-fragment RANKL provides a promising avenue for the advancement of novel therapeutic approaches to osteoporosis.

The excessive accumulation of monosodium urate crystals in joints leads to the pathological condition known as gout. While conventional treatments, which include Non-steroidal Anti-inflammatory Drugs, are available, their short half-life and low bioavailability limit their practical application. To overcome these limitations and leverage the Reactive Oxygen Species (ROS)-rich microenvironment, this study developed a novel ROS-responsive thioketal-linked hyaluronic acid-based micelle loaded with manganese oxide (HTO-MnO) for enhanced treatment. Following the synthesis of the HTO-MnO nanocomplex, the micelle was well characterized and the synthesized micelle were subjected to multiple tests to confirm their efficacy in reducing ROS. In addition, the in-vitro treatment of M1-polarized macrophages showed significant responses at both the gene and protein expression levels. Eventually, in-vivo analysis of the HTO-MnO nanoparticles was performed in the MSU-induced arthritis mouse model. The elevated ROS levels in the ankle joint of the mice triggered the release of MnO nanoparticles from the HTO micelles, suppressing the ROS levels and repolarizing macrophages to their M0 state, thereby effectively mitigating inflammation. This study demonstrates the potential of nanocomplex to reduce ankle swelling and intrinsic ROS levels by targeting M1 macrophages. The results highlight its precise therapeutic mechanism to alleviate inflammation and treat gouty arthritis.

Background: Heat generation in a drug delivery carrier by exposure to near-infrared (NIR) light with excellent tissue transmittance is an effective strategy for drug release and tumor therapy. Because liposomes have amphiphilic properties, they are useful as drug carriers. Liposomes are also very suitable for drug delivery strategies using heat generation by NIR laser because lipid bilayers are easily broken by heat. Thermally generated bubbles from liposomes not only induce drug release, but also enable ultrasound imaging. Methods: Melanin, perfluorohexane (PFH), and 5-fluorouracil (5-FU)-loaded liposomes (melanin@PFH@5-FU-liposomes) that can generate heat and bubble by NIR laser irradiation were prepared by a thin film method. Conversion of light to heat and bubble generation of melanin@PFH@5-FU-liposomes were evaluated using an infrared (IR) thermal imaging camera and an ultrasound imaging system both in vitro and in vivo . To investigate tumor therapeutic effect, NIR laser of 808 nm was used to irradiate tumor site for 10 min after injecting melanin@PFH@5-FU-liposome into tail veins of CT26-bearing mice. Results: Melanin@PFH@5-FU-liposomes showed a spherical shape with a size of 209.6 ± 4.3 nm. Upon NIR laser irradiation, melanin@PFH@5-FU-liposomes exhibited effective temperature increase both in vitro and in vivo . In this regard, temperature increase caused a phase transition of PFH to induce bubble generation dramatically, resulting in effective drug release behavior and ultrasound imaging. The temperature of the tumor site was increased to 52 t and contrast was greatly enhanced during ultrasound imaging due to the generation of bubble. More importantly, tumor growth was effectively inhibited by injection of melanin@PFH@5-FU-liposomes with laser irradiation. Conclusions: Based on intrinsic photothermal properties of melanin and phase transition properties of PFH, melanin@PFH@5-FU-liposomes exhibited effective heat and bubble generation upon NIR laser irradiation. The elevated temperature induced bubble generation, resulting in contrast enhancement of ultrasound imaging. Melanin@PFH@5-FU-liposomes under NIR laser irradiation induced the death of cancer cells, thereby effectively inhibiting tumor growth. These results suggest that melanin@PFH@5-FU-liposomes can be utilized as a promising agent for photothermal tumor therapy and ultrasound imaging.