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CONTEXT: Rotator cuff tear is one of the most common causes of shoulder pain and has become a prominent disease most frequently treated by surgery. OBJECTIVES: To investigate the long-term therapeutic effect of integrative Korean medicine (KM) as a conservative treatment in treating rotator cuff tears. DESIGN: A multicenter observational study. SETTINGS: The settings involve four regional network KM hospitals. PATIENTS: The study participants are 288 patients aged 19-70 with rotator cuff tear identified by radiologist based on magnetic resonance imaging who received integrative KM treatment for the chief complaint of shoulder pain between 1 January 2015 and 31 March 2020. INTERVENTION: None. MAIN OUTCOMES: The primary outcome was the pain score in the affected shoulder, measured by the numeric rating scale (NRS). The secondary outcomes were Shoulder Pain and Disability Index (SPADI), 5-Level Quality of life: EuroQol 5-Dimension (EQ-5D-5L), Patient Global Impression of Change (PGIC), and range of motion (ROM) scores. RESULTS: Eligible patients for MCID achievement analysis for minimally clinical important change were 167, and 109 completed the follow-up survey. The mean NRS pain score in the affected shoulder was 5.80 ± 1.27 at admission, 3.50 ± 1.32 at discharge, and 3.83 ± 2.04 at follow-up.The mean SPADI score was 51.48 ± 20.18 at admission, 37.76 ± 19.23 at discharge, and 24.26 ± 21.80 at follow-up. The improvement at discharge (P-value < 0.001) and follow-up (P-value < 0.001) compared to those at admission was statistically significant. The results also presented a significant improvement in ROM for all motions at discharge after treatment (P-value < 0.001). The number of patients who achieved minimal clinically important difference in NRS was 116 (69.5%) at discharge and 71 (65.1%) at follow-up, and in SPADI was 82 (50.9%) at discharge and 77 (70.6%) at follow-up. CONCLUSION: The results of this study suggested that integrative KM treatment can help improve pain, functional impairment, QoL, and ROM in patients with a rotator cuff tear TRIAL REGISTRATION: NCT04566939.

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Self-healing polymeric materials, engineered to autonomously self-restore damages from external stimuli, are at the forefront of sustainable materials research. Their ability to maintain product quality and functionality and prolong product life plays a crucial role in mitigating the environmental burden of plastic waste. Historically, initial research on the development of self-healing materials has focused on extrinsic self-healing systems characterized by the integration of embedded healing agents. These studies have primarily focused on optimizing the release of healing agents and ensuring rapid self-healing capabilities. In contrast, recent advancements have shifted the focus towards intrinsic self-healing systems that utilize their inherent reactivity and interactions within the matrix. These systems offer the advantage of repeated self-healing over the same damaged zone, which is attributed to reversible chemical reactions and supramolecular interactions. This review offers a comprehensive perspective on extrinsic and intrinsic self-healing approaches and elucidates their unique properties and characteristics. Furthermore, various self-healing mechanisms are surveyed, and insights from cutting-edge studies are integrated.

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In this study, we prepare highly self-healable polymeric coating materials using charge transfer complex (CTC) interactions. The resulting coating materials demonstrate outstanding thermal stability (1 wt% loss thermal decomposition temperature at 420 °C), rapid self-healing kinetics (in 5 min), and high self-healing efficiency (over 99%), which is facilitated by CTC-induced multiple interactions between the polymeric chains. In addition, these materials exhibit excellent optical properties, including transmittance over 91% and yellow index (YI) below 2, and show enhanced weatherability with a ΔYI value below 0.5 after exposure to UV light for 72 h. Furthermore, the self-healable coating materials developed in this study show outstanding mechanical properties by overcoming the limitations of conventional self-healing materials.

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A functional polyurethane based on the heterocyclic group was synthesized and its self-healing and mechanical properties were examined. To synthesize a heterocyclic polyurethane, a polyol and a heterocyclic compound with di-hydroxyl groups at both ends were blended and the blended solution was reacted with a crosslinker containing multiple isocyanate groups. The heterocyclic polyurethane demonstrates better self-healing efficiency than the conventional polyurethane with no heterocyclic groups. Furthermore, unlike the conventional self-healing materials, the heterocyclic polyurethane examined in this study shows an outstanding recovery of the mechanical properties after the self-healing process. These results are attributed to the unique supramolecular network resulting from the strong hydrogen bonding interaction between the urethane group and the heterocyclic group in the heterocyclic polyurethane matrix.

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Thermotoga neapolitana beta-glucosidase (BglA) was subjected to site-directed mutagenesis in an effort to increase its ability to synthesize arbutin derivatives by transglycosylation. The transglycosylation reaction of the wild-type enzyme displays major beta(1,6) and minor beta(1,3) or beta(1,4) regioselectivity. The three mutants, N291T, F412S, and N291T/F412S, increased the ratio of transglycosylation/hydrolysis compared with the wild-type enzyme when pNPG and arbutin were used as a substrate and an acceptor, respectively. N291T and N219T/F412s had transglycosylation/hydrolysis ratios about 3- and 8-fold higher, respectively, than that of the wild-type enzyme. This is due to the decreased hydrolytic activity of the mutant rather than increased transglycosylation activity. Interestingly, N291T showed altered regioselectivity, as well as increased transglycosylation products. TLC analysis of the transglycosylation products indicated that N291T retained its beta(1,3) regioselectivity, but lost its beta(1,4) and beta(1,6) regioselectivity. The altered regioselectivity of N291T using two other acceptors, esculin and salicin, was also confirmed by TLC. The major transglycosylation products of the wild type and N291T mutant were clearly different. This result suggests that Asn-291 is highly involved in the catalytic mechanism by controlling the transglycosylation reaction.

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To develop a new skin whitening agent, arbutin-beta-glycosides were synthesized and evaluated for their melanogenesis inhibitory activities. Three active compounds were synthesized via the transglycosylation reaction of Thermotoga neapolitana beta-glucosidase and purified by recycling preparative HPLC. As compared with arbutin (IC(50 )= 6 mM), the IC(50 )values of these compounds were 8, 10, and 5 mM for beta-D -glucopyranosyl-(1-->6)-arbutin, beta-D: -glucopyranosyl-(1-->4)-arbutin, and beta-D -glucopyranosyl-(1-->3)-arbutin, respectively. beta-D: -Glucosyl-(1-->3)-arbutin also exerted the most profound inhibitory effects on melanin synthesis in B16F10 melanoma cells. Melanin synthesis was inhibited to a significant degree at 5 mM, at which concentration the melanin content was reduced to below 70% of that observed in the untreated cells. Consequently, beta-D: -glucopyranosyl-(1-->3)-arbutin is a more effective depigmentation agent and is also less cytotoxic than the known melanogenesis inhibitor, arbutin.

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The gene encoding beta-glucosidase of the marine hyperthermophilic eubacterium Thermotoga neapolitana (bglA) was subcloned and expressed in Escherichia coli. The recombinant BglA (rBglA) was efficiently purified by heat treatment at 75 degrees C, and a Ni-NTA affinity chromatography and its molecular mass were determined to be 56.2 kDa by mass spectrometry (MS). At 100 degrees C, the enzyme showed more than 94% of its optimal activity. The half-life of the enzyme was 3.6 h and 12 min at 100 and 105 degrees C, respectively. rBglA was active toward artificial (p-nitrophenyl beta-D: -glucoside) and natural substrates (cellobiose and lactose). The enzyme also exhibited activity with positional isomers of cellobiose: sophorose, laminaribiose, and gentiobiose. Kinetic studies of the enzyme revealed that the enzyme showed biphasic behavior with p-nitrophenyl beta-D: -glucoside as the substrate. Whereas metal ions did not show any significant effect on its activity, dithiothreitol and beta-mercaptoethanol markedly increased enzymatic activity. When arbutin and cellobiose were used as an acceptor and a donor, respectively, three distinct intermolecular transfer products were found by thin-layer chromatography and recycling preparative high-performance liquid chromatography. Structural analysis of three arbutin transfer products by MS and nuclear magnetic resonance indicated that glucose from cellobiose was transferred to the C-3, C-4, and C-6 in the glucose unit of acceptor, respectively.

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