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Triboelectric nanogenerators (TENGs) are promising candidates replacing conventional batteries in wearable devices, owing to their self‐powering properties. Although TENGs can convert mechanical energy into electrical energy, excessive mechanical stresses can degrade their performance. Moreover, conformal adhesion to skin is required to improve its performance in wearable devices. Here, a stretchable, adhesive, and self‐healing single‐electrode TENG with a multifunctional hydrogel‐elastomer double layer is developed. Carbon nanotubes (CNTs)‐doped hydrogel is used as the electrode. Subsequently, the electrode is covered with an Ecoflex elastomer that acted as a triboelectrification layer. The soft tissue‐like properties of the hydrogel allow conformal adhesion to nonplanar skin, whereas the dynamic polymer network of the hydrogel endows toughness and ability to self‐heal (within 5 min) against external damage. The TENG demonstrates an output voltage and current peak at 180 V and 0.8 µA. Moreover, it can generate a maximum power peak at 37.8 mW m−2, which is sufficient to power small electronics like stopwatches and light‐emitting diodes, with a power management circuit. The proposed TENG devices can function as telecommunication touch panels via Morse code. Thus, this study presents a promising approach for advancing the flexible power supplies and self‐powered sensors that can be applied to wearable devices. [ABSTRACT FROM AUTHOR]

Developing thin, highly stretchable coatings that inhibit the undesirable adhesion of biological substances on soft and high‐water‐content biomaterial surfaces is an area of significant interest. In this study, a stretchable antifouling coating named lubricant‐infused poly(1,3,5,7‐tetramethyl‐1,3,5,7‐tetravinyl cyclotetrasiloxane) (V4D4) is introduced interface with perfluoropolymer (L‐VIP). The stretchable adhesive‐perfluoropolymer bilayer comprises stretchable adhesive polymer (V4D4) and perfluoropolymer (1H,1H,2H,2H‐perfluorooctyl methacrylate (FOMA)). The bilayer exhibits a strong affinity with the lubricant, imparting exceptional antifouling and slippery properties. L‐VIP coating displays superior fouling resistance against plasma proteins related to foreign body reactions (FBR) and biofilm‐forming bacteria. The coating exhibits impressive elastic limits exceeding 200% strain and exceptional stability under repeated cyclic stretching (> 2000 cycles at 150% strain) while maintaining its antifouling properties. Furthermore, the coating presents dielectric performance under accelerated aging conditions at a temperature of 70° and constant voltage stress of 10 V s−1 for over 50 days. To assess the biocompatibility of the L‐VIP coating, a series of in vitro and in vivo experiments are conducted, confirming its non‐toxicity for biomedical applications. It is expected that the stretchable L‐VIP coating will enhance medical devices' longevity and help prevent bacterial infections, the formation of biofilms, and the nonspecific adherence of biological substances after implantation. [ABSTRACT FROM AUTHOR]

Bone homeostasis is maintained by tightly coordinated activities of bone-forming osteoblasts and bone-resorbing osteoclasts. In the present report, the role of Mer tyrosine kinase (MerTK) in bone metabolism was investigated. The expression of MerTK decreased upon BMP2 stimulation of osteoblast precursors. The femurs of Mertk -deficient mice showed significantly increased bone volume with concomitant increase of bone formation and reduction in bone resorption. These bone phenotypes were attributed to the increased osteoblast differentiation and mineralization accounted by the enhanced β-catenin and Smad signaling in the absence of MerTK in osteoblast precursors. Although the Mertk -deficient bone marrow macrophages were predisposed to enhanced osteoclast differentiation via augmented Ca2+-NFATc1 signaling, the dramatic increase of Tnfsf11b/Tnfsf11 (Opg/Rankl) ratio in Mertk knockout bones and osteoblast precursors corroborated the reduction of osteoclastogenesis in Mertk deficiency. In ligature-induced periodontitis and ovariectomy models, the bone resorption was significantly attenuated in Mertk -deficient mice compared with wild-type control. Taken together, these data indicate novel role of MerTK in bone metabolism and suggest a potential strategy targeting MerTK in treating bone-lytic diseases including periodontitis and osteoporosis. [ABSTRACT FROM AUTHOR]

Lipid biosynthesis is recently studied its functions in a range of cellular physiology including differentiation and regeneration. However, it still remains to be elucidated in its precise function. To reveal this, we evaluated the roles of lysophosphatidic acid (LPA) signaling in alveolar bone formation using the LPA type 2 receptor (LPAR2) antagonist AMG‐35 (Amgen Compound 35) using tooth loss without periodontal disease model which would be caused by trauma and usually requires a dental implant to restore masticatory function. In this study, in vitro cell culture experiments in osteoblasts and periodontal ligament fibroblasts revealed cell type‐specific responses, with AMG‐35 modulating osteogenic differentiation in osteoblasts in vitro. To confirm the in vivo results, we employed a mouse model of tooth loss without periodontal disease. Five to 10 days after tooth extraction, AMG‐35 facilitated bone formation in the tooth root socket as measured by immunohistochemistry for differentiation markers KI67, Osteocalcin, Periostin, RUNX2, transforming growth factor beta 1 (TGF‐β1) and SMAD2/3. The increased expression and the localization of these proteins suggest that AMG‐35 elicits osteoblast differentiation through TGF‐β1 and SMAD2/3 signaling. These results indicate that LPAR2/TGF‐β1/SMAD2/3 represents a new signaling pathway in alveolar bone formation and that local application of AMG‐35 in traumatic tooth loss can be used to facilitate bone regeneration and healing for further clinical treatment. [ABSTRACT FROM AUTHOR]

Hydrogels are used in wound dressings because of their tissue‐like softness and biocompatibility. However, the clinical translation of hydrogels remains challenging because of their long‐term stability, water swellability, and poor tissue adhesiveness. Here, tannic acid (TA) is introduced into a double network (DN) hydrogel consisting of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAA) to realize a tough, self‐healable, nonswellable, conformally tissue‐adhesive, hemostatic, and antibacterial hydrogel. The TA within the DN hydrogel forms a dynamic network, enabling rapid self‐healing (within 5 min) and offering effective energy dissipation for toughness and viscoelasticity. Furthermore, the hydrophobic moieties of TA provide a water‐shielding effect, rendering the hydrogel nonswellable. A simple chemical modification to the hydrogel further strengthens its interfacial adhesion with tissues (shear strength of ≈31 kPa). Interestingly, the TA also can serve as an effective hemostatic (blood‐clotting index of 58.40 ± 1.5) and antibacterial component, which are required for a successful wound dressing. The antibacterial effects of the hydrogel are tested against Escherichia coli and Staphylococcus aureus. Finally, the hydrogel is prepared in patch form and applied to a mouse model to test in vivo biocompatibility and hemostatic performances. [ABSTRACT FROM AUTHOR]

Summary: Quantification of some important elements, including several heavy metals, and assessment of health risks associated with rice consumption was conducted. Twelve different rice varieties were analysed for fourteen metals i.e. As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, Sr, U, and Zn using Inductively Coupled Plasma–Mass Spectrometry (ICP‐MS). In addition, arsenic species were separated and determined by High‐Performance Liquid Chromatography coupled with ICP‐MS. The As levels ranged from 24.16 to 178.66 μg kg−1, while Cd levels varied from 31.38 to 155.88 μg kg−1. The principal component analysis clearly differentiates traditional and non‐traditional varieties. The maximum Estimated Daily Intake (EDI) value, 120.56 μg kg−1 bw day−1, was reported for Zn from Kekulu Samba, while the highest Cancer Risk (CR) value, 1.17 × 10−02, was reported for Cd from red raw rice. The Madathawalu rice recorded the highest Target Hazard Quotient (THQ) value of 5.51. The EDI, CR, and THQ levels showed some health risks for some rice varieties. The most predominant species detected was As(III), followed by As(V), and the total inorganic As level ranged from 77.3 to 91.3%. THQ and CR levels suggested considerable potential non‐carcinogenic risk and carcinogenic risk due to the consumption of rice. [ABSTRACT FROM AUTHOR]

To understand the mechanisms underlying tooth morphogenesis, we examined the developmental roles of important posttranslational modification, O‐GlcNAcylation, which regulates protein stability and activity by the addition and removal of a single sugar (O‐GlcNAc) to the serine or threonine residue of the intracellular proteins. Tissue and developmental stage‐specific immunostaining results against O‐GlcNAc and O‐GlcNAc transferase (OGT) in developing tooth germs would suggest that O‐GlcNAcylation is involved in tooth morphogenesis, particularly in the cap and secretory stage. To evaluate the developmental function of OGT‐mediated O‐GlcNAcylation, we employed an in vitro tooth germ culture method at E14.5, cap stage before secretory stage, for 1 and 2 days, with or without OSMI‐1, a small molecule OGT inhibitor. To examine the mineralization levels and morphological changes, we performed renal capsule transplantation for one and three weeks after 2 days of in vitro culture at E14.5 with OSMI‐1 treatment. After OGT inhibition, morphological and molecular alterations were examined using histology, immunohistochemistry, real‐time quantitative polymerase chain reaction, in situ hybridization, scanning electron microscopy, and ground sectioning. Overall, inhibition of OGT resulted in altered cellular physiology, including proliferation, apoptosis, and epithelial rearrangements, with significant changes in the expression patterns of β‐catenin, fibroblast growth factor 4 (fgf4), and sonic hedgehog (Shh). Moreover, renal capsule transplantation and immunolocalizations of Amelogenin and Nestin results revealed that OGT‐inhibited tooth germs at cap stage exhibited with structural changes in cuspal morphogenesis, amelogenesis, and dentinogenesis of the mineralized tooth. Overall, we suggest that OGT‐mediated O‐GlcNAcylation regulates cell signaling and physiology in primary enamel knot during tooth development, thus playing an important role in mouse molar morphogenesis. [ABSTRACT FROM AUTHOR]

A series of 1,4‐bis(N‐alkylpyrrolidinium)butane salts combined with Br−, I−, PF6−, and Tf2N− anions were newly designed and synthesized. In nonpolar CDCl3 solution, the axial and equatorial proton peaks of the bis‐pyrrolidinium cation ring are distinguished in 1H NMR. Also, the strengths of ion paring could be estimated from the 1H NMR chemical shift changes of the bridge and pyrrolidinium proton peaks. 1,4‐Bis(N‐hepthylpyrrolidinium)butane I− is an organic ionic plastic crystal showing the lowest fusion entropy value (ΔSf = 3.4 J K·mol−1). Softer crystalline morphologies were found by polarized optical microscope images at plastic crystal phase of each sample and the results were corresponding to differential scanning calorimetry results. 1,4‐Bis(N‐ethylpyrrolidinium)butane Tf2N− showed the softest crystal phase. Ionic conductivity changes and electrochemical stabilities of the bis‐pyrrolidinium PF6− and Tf2N− salts were also measured, and they were stable up to 4.3 V (vs. Li/Li+) and expected to be applied as an electrolyte component. [ABSTRACT FROM AUTHOR]

Navigation of nanoparticles to target sites of blood flow disturbance markedly upgrades the diagnostic paradigm in vascular medicine. The theranostic treatment of pre‐stenotic vessels can prevent the irreversible occlusion process effectively. Here, these nanotheranostic functions are established by displaying CDK9(cyclin‐dependent kinase 9)‐targeting peptide (P.) onto nanovesicles (NV) and liposomes using the navigation function and subsequent binding‐on signaling of P. as a game‐changer. When rabbit vessels are allografted with injecting contrast‐loaded P. liposomes, the case‐dependent stenotic degree after 2–6 weeks can be diagnosed accurately within 2–4 days via computed tomography imaging with cross‐validation in a mouse model of partial carotid ligation. Furthermore, the anti‐CDK9 signaling of P. NV is activated post‐targeting and effectively prevents vascular stenosis by suppressing inflammation and lipotoxicity in the vessels, serum, and/or liver. CDK9 targeting is confirmed using computer, in vitro, and in vivo models. This study demonstrates an unprecedented nanotheranostic function for future clinical applications. [ABSTRACT FROM AUTHOR]

Matrix-assisted laser desorption ionization - mass spectrometry imaging of erlotinib reveals a limited tumor tissue distribution in a non-small-cell lung cancer mouse xenograft model GLO:F2H7/01jul21:ctm2481-fig-0002.jpg PHOTO (COLOR): 2 Erlotinib-resistant mouse xenograft model with H1299 cells and erlotinib distribution in tumor, liver, and kidney tissue. Although erlotinib still has a binding affinity to the target protein, EGFR, even in the H1299 tumor cells, the reduced distribution within in tumor tissues suggests a new mechanism of erlotinib resistance I in vivo i . H1299 tumor tissue, liver, and kidney were isolated from the xenograft mice previously treated with either vehicle ( I N i = 4) or erlotinib ( I N i = 5) (10 mg/kg) for analyzing erlotinib distribution. [Extracted from the article]

Certified reference materials (CRMs), KRISS CRM 111‐01‐010 and 111‐01‐011, were first developed in Korea to provide SI‐traceability in the measurement of triglycerides (TGs) in human frozen serum. For absolute TG quantification in KRISS CRMs, isotope dilution‐liquid chromatography–tandem mass spectrometry (ID‐LC–MS/MS) was used. Both certification and short‐term stability assessment of TG in KRISS CRMs were performed for each of 10 and eight selected units. The TG certified values and expanded uncertainties in KRISS CRMs were as follows: 0.608 ± 0.025 mmol/kg for CRM 111‐01‐010 and 1.825 ± 0.072 mmol/kg for CRM 111‐01‐011. The short‐term TG stability results were not significantly changed relative to the certified values, and therefore both KRISS CRMs were stable during the monitoring period at each temperature. Based on our experiments, the developed KRISS CRMs can provide accurate, precise, and reproducible TG measurements in human frozen serum for clinical laboratories with SI‐traceability. [ABSTRACT FROM AUTHOR]

Abstract: 4D printing is an extension to 3D printing whereby a printed shape programmatically undergoes shape transformation through external stimulations. There is an increasing interest in this field because of its potential applications. However, many demonstrated shape transformations work on simple and limited geometrical shapes. In this work, the formation of a cylinder from a printed flat dual‐layer beam when exposed to ethanol is demonstrated. The newly formed cylinder retains its shape even when the ethanol is removed through the use of a locking mechanism. The proposed method can be used for building medical stents or various sensors and actuators that require cylindrical shapes. [ABSTRACT FROM AUTHOR]

Here, we evaluated the effect of linkers conjugating a chlorin-based photosensitizer, 2-[1-hexyloxyethyl]-2-devinyl pyropheophorbide-a ( HPPH), and folic acid to target cancer cells. Folate- HPPH conjugates with peptide, polyethylene glycol ( PEG), peptoid, or 7-aminoheptanoic acid ( AHA) linkers were synthesized on a solid-phase and evaluated for photodynamic therapy ( PDT) efficacy. Compared to free HPPH, the folate-linker- HPPHs were effectively internalized into tumor cells and exhibited superior PDT effect upon irradiation. Tumor-targeting PDT efficacy was influenced by linker variation, with in vitro photocytotoxicities of peptide > PEG > AHA > peptoid, paralleling water solubility of the linkers. Thus, linker choice significantly affects targeted PDT efficacy providing useful information for linker design. [ABSTRACT FROM AUTHOR]

Background: We evaluated the efficacy of tailored therapy based on point mutation presence identified with the dual‐priming oligonucleotide (DPO)‐based multiplex polymerase chain reaction (PCR) method compared with concomitant therapy. Materials and methods: Subjects were randomly assigned concomitant therapy (amoxicillin 1 g, clarithromycin 500 mg, metronidazole 500 mg, and lansoprazole 30 mg twice/day for 14 days) or tailored therapy (amoxicillin 1 g, clarithromycin 500 mg, and lansoprazole 30 mg twice/day for 14 days in point mutation‐negative subjects; and amoxicillin 1 g, metronidazole 500 mg, and lansoprazole 30 mg twice/day for 14 days in point mutation‐positive subjects). Results: A total of 397 and 352 subjects were included in the intention‐to‐treat (ITT) and per‐protocol (PP) analyses, respectively. Point mutations were identified in 25.9% of the subjects. The overall eradication rate was not significantly different between the groups by ITT (86.2% vs 81.6%, P = .132) and PP analyses (90.2% vs 86.5%, P = .179). There was no significant difference in the eradication rates between the groups in both the point mutation‐negative subjects (91.7% vs 87.3%, P = .154) and the point mutation‐positive subjects (71.2% vs 64.7%, P = .312). The eradication rates were significantly lower in the point mutation‐positive subjects than in the point mutation‐negative subjects in both the concomitant and tailored therapy groups. Conclusions: Tailored therapy based on point mutation presence identified with the DPO‐based multiplex PCR method was as effective as concomitant therapy. The eradication rates of both therapy regimens were suboptimal in point mutation‐positive subjects. [ABSTRACT FROM AUTHOR]

A correction to the article "Effects of Alcoholic Solvents on the Conductivity of Tosylate-Doped Poly (3,4-Ethylenedioxy-Thiophene) (PEDOT-OTs)" that was published in the previous issue is presented.

Bortezomib is a therapeutic proteasome inhibitor with antimyeloma activity and polyphenols are well known compounds that exert antiproliferative effects against tumuors. We attempted to co-treat myeloma cells with bortezomib and polyphenols, anticipating a synergistic effect. However, the anticancer activity of bortezomib was blocked by the polyphenols. The structural features of the polyphenols correlated strikingly with their antagonistic effect; in particular, the presence or absence of a vicinal diol moiety was the key element for effective blockage of the anticancer function of bortezomib. We speculated that the vicinal diols in the polyphenols interact with the boronic acid of bortezomib and convert the active triangular boronic acid of bortezomib to an inactive tetrahedral boronate, thus abolishing the antimyeloma activity of bortezomib. We confirmed this hypothesis by (11)B nuclear magnetic resonance spectroscopy and an in vitro assay on multiple myeloma (MM) cell lines and primary myeloma cells from patients. Based on these findings, restriction of the intake of natural polyphenols in foods or vitamin supplements during bortezomib treatment in MM patients should be considered.