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Synthesis of polycarbonates (PCs) from isosorbide (ISB) monomers has been recently investigated. However, compared to bisphenol A, PCs face challenges in commercialization because their high rigidity renders it difficult to increase their molecular weight, resulting in high brittleness. To address these limitations, a flexible co‐monomer, ethoxylated ISB (EI5), was mixed with ISB to produce ISB/EI5‐based PCs. The structures of the ISB/EI5‐based PCs were controlled by varying the ISB/EI5 ratio from 100/0 to 60/40 mol%. Films were fabricated, and their thermal, optical, and mechanical properties and degradability were investigated. With increasing EI5 content, the thermal processability of the ISB/EI5‐based PCs improved, and the produced films exhibited excellent visible light transmittance and UV‐blocking effects. The mechanical properties of the ISB/EI5‐based PCs indicated sufficient tensile strength (σ = 89.7–72.9 MPa), competitive to that of commercial PC, and the properties could be controlled by adjusting the ISB/EI5 ratio. The contact angle and hydrolysis behavior of the ISB/EI5‐based PC films indicated increased surface hydrophilicity and increased degradation rate with increasing EI5 content. In conclusion, the structural control of the ISB/EI5‐based PCs enhanced their moldability and degradability, suggesting their potential commercial utilization. [ABSTRACT FROM AUTHOR]

This research investigates the enhancement effects of basalt fibers (BFs) and kraft lignin (KL) as natural additives on the mechanical properties of acrylonitrile–butadiene–styrene (ABS)‐based composites. Initially, BF was incorporated into ABS as a fiber reinforcement, and its mechanical properties were evaluated. It was observed that an increase in BF content in ABS led to an increase in the tensile strength while the impact strength tended to decrease. Subsequently, the potential of lignin or modified lignin as interfacial compatibilizers was assessed to improve the miscibility between ABS and BF. The modification of lignin was achieved via esterification by using esterifying agents (acetic anhydride [C2_Ac], propionic anhydride [C3_Pr], and butyric anhydride [C4_Bu]). At the optimal conditions (30 wt% of BF, 15phr of AcKL), the mechanical properties of ABS/BF/AcKL composite presented a 48.1% improvement in tensile strength and a 27.4% enhancement in impact strength compared to those of ABS/BF composite. The fracture surface analysis of the composite revealed that the esterified lignin enhances the compatibility between components, thereby filling the gaps present at the matrix‐fiber interface. These results suggest promising applications for multi‐component composite materials. [ABSTRACT FROM AUTHOR]

Plant and fruit extracts exhibit fewer side effects than pharmaceuticals and can display therapeutic qualities. Consequently, they have attracted increased attention among health-conscious individuals, and many studies related to their health-promoting effects are being actively conducted. Vitis coignetiae is well-known for its antioxidant, anti-inflammatory, and anticancer properties. However, the immune-enhancing effects of Vitis coignetiae have not yet been studied. In this study, Vitis coignetiae extract (VCE) increased immune-related activity in Wistar rat splenocytes and cyclophosphamide (Cy)-induced immunosuppressed rats. In splenocytes, VCE was nontoxic up to 300 μg/mL and increased cell viability in the presence of Cy. VCE also recovered Cy-induced decreases in cytokine (tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), interleukin-2 (IL-2), and IL-12) levels and natural killer (NK) cell activity in splenocytes. In Cy-induced immunosuppressed rats, VCE protected against Cy-induced spleen tissue damage and decreases in body and spleen weight, cytokine (TNF-α, IFN-γ, IL-2, and IL-12) levels, and NK cell activity. We also observed recovery of immunoglobulin G (IgG) and IgM levels following VCE treatment. In conclusion, the ability of VCE to restore immune activity from an immunosuppressive state to normal levels suggests its immune-enhancing efficacy. Therefore, VCE may have the potential for application in the development of immune-enhancing functional foods and medicines. [ABSTRACT FROM AUTHOR]

Polylactides (PLAs) and lactide copolymers are biodegradable, compostable, and derived from renewable resources, offering a sustainable alternative to petroleum-based synthetic polymers owing to their advantages of comparable mechanical properties with commodity plastics and biodegradability. Their hydrolytic stability and thermal properties can affect their potential for long-lasting applications. However, stereocomplex crystallization is a robust method between isomer PLAs that allows significant amelioration in copolymer properties, such as thermal stability, mechanical properties, and biocompatibility, through substantial intermolecular interactions amid l-lactyl and d-lactyl sequences, which have been the key approach to initial degradation rate and further PLA applications. It was demonstrated that the essential parameters affecting stereocomplexation are the mixing ratio and the chain length of each unit sequence. This study deals with the molecular weight, one of the specific interactions between isomers of PLAs. A solution polymerization method was applied to control molecular weight and chain architecture. The stereocomplexation was monitored with DSC. It was confirmed that the lower molecular weight polymer showed a higher degradation rate, as a hydrolyzed fragment having a molecular weight below a certain length dissolves into the water. To systematically explore the critical contribution of molecular weights, the Langmuir system was used to observe the stereocomplexation effect and the overall degradation rate. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficacy of Chlorin e6 (Ce6)-based photodynamic therapy (PDT) for anti-obesity activities in high-fat-diet (HFD)-induced obesity mouse models. We induced obesity in C57BL/6 mice by HFD and administered Ce6 (2.5 or 5 mg/kg) orally with 3 h of incubation. The mice were then exposed to light of high fluence rate (4.96 mW/cm2) or low fluence rate (2.56 mW/cm2) in the designed LED mouse chamber 2–3 days a week for up to 8 weeks. The study also analyzed the pharmacokinetics and optimization of the drug by evaluating the absorption, distribution, metabolism, and excretion (ADME) of Ce6 in the rat models. Both low doses (2.5 mg/kg) and high doses (5 mg/kg) of Ce6 with high irradiation dose showed better anti-obesity effects than other groups with decreased body weight. The lipid accumulation in the liver and adipocyte size in epididymal adipose tissues were found to be decreased by Ce6-PDT in comparison to vehicle-treated HFD groups. We also observed increased levels of the lipidomic biomarkers, such as leptin and LDL cholesterol, while observing decreasing levels of total cholesterol and adiponectin in the Ce6-PDT-treated mice. These findings may provide valuable insight into Ce6-PDT as an alternative and non-invasive therapeutic methodology for obesity and obesity-related diseases. [ABSTRACT FROM AUTHOR]

Simple Summary: Enzymatic porcine placental hydrolyzing (EPPH) was extracted using enzymatic hydrolysis to extract placental-derived peptides recently reported as excellent bioactive substances, and EPPH was administered to HepG2 cells and alcohol-derived animal models. As a result, it was confirmed that inflammation and antioxidant activity could be regulated through CYP2E1 inhibition. Through these results, we confirmed that the antioxidant and anti-inflammatory effects mediated by CYP2E1 regulation of EPPH have potential for improvement and protection of liver disease in alcoholic liver disease animal models. Alcoholic liver disease is associated with the production of highly reactive free radicals by ethanol and its metabolites. Free radicals not only induce liver oxidation and damage tissues, but also stimulate an inflammatory response in hepatocytes, leading to severe liver disease. In order to improve alcoholic liver disease, enzymatic porcine placenta hydrolysate was studied by exploring various materials. Enzymatic porcine placenta hydrolysate (EPPH) contains various amino acids, peptides, and proteins, and is used as a useful substance in the body. In this study, changes were confirmed in indicators related to the antioxidant efficacy of EPPH in vitro and in vivo. EPPH inhibits an EtOH-induced decrease in superoxide dismutase and catalase activity through inhibition of free radicals without endogenous cytotoxicity. EPPH has been observed to have a partial effect on common liver function factors such as liver weight, ALT, AST, ALP, and GGT. In addition, EPPH affected changes in fat regulators and inflammatory cytokines in blood biochemical assays. It was confirmed that EPPH was involved in fat metabolism in hepatocytes by regulating PPARα in an alcoholic liver disease animal model. Therefore, EPPH strongly modulates Bcl-2 and BAX involved in apoptosis, thereby exhibiting cytochrome P450 (CYP)-inhibitory effects in alcoholic liver disease cells. As a result, this study confirmed that EPPH is a substance that can help liver health by improving liver disease in an alcoholic liver disease animal model. [ABSTRACT FROM AUTHOR]

Two kinds of magnetization types in isotropic permanent magnets are introduced and analyzed by FEM: One is a radial magnetization type, the other is a parabolic one. From the results of FEA, it is found that the permanent magnet with parabolic magnetization has low leakage flux and high interior surface flux density despite using a nonmagnetic material backyoke. The magnetization types are applied to the spindle motor for optical disc media and verified by comparing the results of FEA with experimental results. As a result it is shown that the permanent magnet motor using the parabolic magnetization can consist of the magnet with a nonmagnetic material backyoke. Index terms - NdFeB bonded magnet, parabolic magnetization, isotropic, backyoke, spindle motor

This paper deals with the analysis of the generated torque of the hysteresis motor using finite element method. The material property of the hysteresis ring in the hysteresis motor is characterized by the asymmetric two dimensional magnetic permeability tensor. The torque has been computed effectively by using permeability tensor instead of full hysteresis modeling or Maxwell stress tensor. The proposed method has been applied to the sample hysteresis motor to compute the torque and the results are in good agreement with the experimental results. Index terms - Torque computation, hysteresis motors, finite element methods, asymmetric magnetic permeability tensor

Portulaca oleracea L. is a traditional oriental medicine known for its pharmacological effects. The present study aimed to investigate the immunostimulatory effects of PPCE on cyclophosphamide-stimulated rat model and in isolated spleen cells. The result showed that PPCE exerted an immunostimulatory effect in vivo and in vitro. Specifically, PPCE significantly enhanced splenocyte proliferation and upregulated inflammatory cytokines (IL-2, IL-12, TNF-α, and IFN-γ) and NK cell activity in vitro. The immunostimulatory effect was further investigated through various immunological assays. Oral administration of PPCE increased the swimming time and number of immune cells in rats. Histological analysis revealed that PPCE administration exerted splenic recovery. Thus, P. oleracea L. based complex extracts may be used as an immunostimulatory agent in medicine or functional foods. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the immunity-enhancing effects of Orostachys japonicus A. Berger (OJ). To examine the immune protective effect in vitro, primary mouse splenocytes were treated with water or ethanol extracts of OJ in the absence or presence of cyclophosphamide (CY), which is a cytotoxic, immunosuppressive agent. The extracts increased the propagation of splenocytes and inhibited CY-induced cytotoxicity. Further, to examine the immunostimulatory effects in vivo, adult Wistar rats were orally administered OJ extracts with or without CY treatment. With the administration of OJ extracts, CY-treated immunosuppressed rats showed improved physical endurance, as assessed by the forced swim test. In addition, extract administration increased not only the number of immunity-related cells but also the levels of plasma cytokines. OJ extracts also recovered splenic histology in CY-treated rats. These findings suggest that an OJ regimen can enhance immunity by increasing immune cell propagation and specific plasma cytokine levels. [ABSTRACT FROM AUTHOR]

Complex oil of Zanthoxylum schinifolium and Perilla frutescens seed (ZPCO) is used as a traditional medicine due to its pharmacological activities. The aim of this study was to investigate the immunostimulatory effect of ZPCO in isolated splenocytes as well as in an immunosuppressed rat model, which was generated via oral administration of cyclophosphamide. Notably, our results showed that ZPCO exerted an immunity-enhancing effect both in vitro and in vivo. Specifically, ZPCO treatment enhanced the viability and inflammatory cytokine production of splenocytes and NK cell activity in vitro. Moreover, this product improved host defense under immunosuppressive conditions by increasing the number of immune cells and promoting the expression of cytokines involved in immune responses. Our results suggest that complex oil including Z. schinifolium should be explored as a novel immunostimulatory agent that could potentially be used for therapeutic purposes or as an ingredient in functional foods. [ABSTRACT FROM AUTHOR]

To improve the mechanical and thermal properties of polyurethane, two prepolymers, polyurethane acrylate (PUA) and epoxy acrylate (EPA) which have acrylate-ended groups, were synthesized. The obtained prepolymers were homogeneously mixed with various compositions and cured by UV. After UV curing, the properties of PU/EP copolymers were investigated by using Fourier-transform infrared spectroscopy, universal testing machine, dynamic mechanical thermal analysis and thermogravimetric analysis. The thermal and tensile properties of PU/EP copolymers gradually increased with the amount of EP due to the intermolecular interaction whereas their elongation properties decreased. These results indicate that the copolymerization of PU with EP could control their mechanical properties. [ABSTRACT FROM AUTHOR]

Two type of triblock copolymers [poly(l-lactide)-b-perfluoro polyether-b-poly(l-lactide) (fluoro l-PLA) and poly(d-lactide)-b-perfluoro polyether-b-poly(d-lactide) (fluoro d-PLA)] (fluoro PLAs) were synthesized by ring-opening polymerization. The synthesized triblock copolymers showed more hydrophobic properties than pristine l-PLA due to the perfluoro polyether (PFPE). To control the surface properties, the blends were prepared by mixing fluoro PLAs with l-PLA. The degradation rates of the fluoro PLAs/l-PLA blends were retarded due to the surface segregation of PFPE which has lower surface energy. In case of the fluoro d-PLA/l-PLA blends, however, the stereocomplex formation between the l-lactide and d-lactide sequences enhanced the thermal and enzymatic stabilities of l-PLA. As a result, the biodegradability of l-PLA can be controlled by copolymerization or the formation of a stereocomplex. [ABSTRACT FROM AUTHOR]

To develop carbon dioxide (CO2)-reducible polymeric materials, block copolymers (PLA-PEC-PLA) of CO2-reducible polymers, poly(lactide) (PLA) and poly(ethylene carbonate) (PEC) were synthesized by the ring-opening polymerization of lactide in the presence of PEC diol using stannous octoate. Differential scanning calorimetry and contact angle measurements showed that the incorporation of the PEC block decrease the crystallinity of PLA and increases the hydrophilicity and flexibility due to its compatibility. The enzymatic degradation in Tris-HCl buffer containing proteinase K showed that the degradation rate of L-PLA-PEC-L-PLA was faster than that of L-PLA due to the decreased crystallization and increased hydrophilicity after copolymerization as well as degradation of PEC. [ABSTRACT FROM AUTHOR]

A biocompatible polymer composite film was prepared by casting method of the mixed solution of poly(L-lactide) (PLA) and lotus leaf powder (LLP) in chloroform. The obtained composite film showed hydrophobic properties. The surface wettability and change in the surface morphology of the film before and after degradation in the enzyme solution were analyzed by contact angle measurement and high resolution scanning electron microscopy. The degradation rate of PLA could be controlled by mixing the right composition of LLP to PLA. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Constipation is one of the most common gastrointestinal complaints worldwide. This study examined the effects of fig (Ficus carica L.) paste for the treatment of loperamide-induced constipation in a rat model. Methods: Animals were divided into one normal control group and four experimental groups (0, 1, 6, and 30g/kg). Loperamide (2mg/kg, twice per day) was injected intraperitoneally to induce constipation in the four experimental groups. Fig paste was administered for 4weeks to assess its anti-constipation effects. Results: Fecal pellet number, weight and water content were increased in the fig-treated groups as compared to the control group. Reductions in body weight and increased intestinal transit length were observed in the fig-treated groups. Fecal pellet number was reduced in the distal colons of the fig-treated rats. Exercise and ileum tension increased in the experimental groups as compared to the control group. According to histological analyses, the thickness of the distal colon and areas of crypt epithelial cells that produce mucin were increased in the fig-treated groups in a dose-dependent manner. Conclusion: Constipation was decreased when fig fruit was fed to rats. Specifically, fecal number, weight, and water content, as well as histological parameters such as thickness and mucin areas in the distal colon were improved. Fig treatment may be a useful therapeutic and preventive strategy for chronic constipation. [Copyright &y& Elsevier]

A series of fully-acylated dextrin esters (DS = 3) with varying side-chain lengths (C2-12) were synthesized by heterogeneous esterification using trifluoroacetic anhydride/carboxylic acid. The influence of side-chain lengths on structure and properties of dextrin esters were investigated by structural, thermal, mechanical and hydrophobic analysis. The thermal stability of dextrin was enhanced by esterification, presenting ca. 40-60 °C higher decomposition temperatures than that of neat-dextrin. The transition temperatures of melting and crystallization were not observed for all dextrin esters because they were amorphous polymers. The glass transition temperature (Tg) was not observed in dextrin but was observed in dextrin esters. As increasing side-chain length, Tgs of dextrin esters decreased ranged from 162.2 °C (C2) to 49.2 °C (C12). Colorless and transparent dextrin ester films were prepared to measure the film properties. Tensile strength of dextrin ester films tended to decrease with increasing side-chain lengths, whereas the elongation at break increased. And, dextrin ester films showed significantly increased hydrophobicity with a contact angle of up to 102° (C12). [ABSTRACT FROM AUTHOR]