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Incorporating lightweight aggregate (LWA) in concrete decreases its density. The high porosity of LWA contributes to low density but also high absorption characteristics. LWA absorbs water even in ...

The amount and properties of fillers greatly affect the workability of sulfur composites. In addition, modified sulfur has fluidity only above approximately 115 °C, and its rheology may depend on the temperature. This study aimed to mainly quantify the effects of mixing temperature and filler particle characteristics on the yield stress and viscosity of fresh sulfur composites by applying suspension rheology theory. Sulfur composites containing mineral fillers, such as different blends of fly ash and Portland cement, were examined. The test results revealed that the yield stress of the sulfur composites was influenced by both the type and volumetric ratio of fillers, whereas the viscosity was governed by the specific surface area of filler particles. At 140 °C, the sulfur composites attained a higher yield stress and viscosity than at 120 °C. In addition, the intrinsic viscosity of the sulfur composites was dependent on the filler type and not on its volume ratio. The sulfur composites were well described by conventional yield and viscosity models commonly applied for suspension materials, when the filler volume ratio was less than 30%.

Background/Aim: Dark tea, made by fermentation of tea leaves using microorganisms, is well known for its anti-obesity effect; however, studies to identify this effect have not been sufficiently conducted. Herein, the anti-obesity effects of post-fermented dark tea were studied in high-fat diet mouse. Materials and Methods: Obesity was induced through a high-fat diet in C57BL/6 mice, and then dark tea extract powder (DTP) was orally administered daily for 12 weeks to evaluate the body and organ weights. Changes in the biochemical markers of obesity were evaluated to study the mechanism of the anti-obesity effects of DTP. Results: When DTP was administered to obesity mice, the weight and food intake reduced, blood aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) decreased, whereas high-density lipoprotein cholesterol (HDL-C) increased. Histopathology showed that steatosis and inflammation scores were reduced within the liver and adipocyte sizes were reduced within epididymal adipocyte. In addition, a significant decrease in blood insulin and hepatic TG and a significant increase in blood adiponectin were also confirmed. The results of western blot and qPCR in week 12, showed a significant decrease in the mRNA and protein levels of C/EBPα, and the mRNA levels of PPARγ in the liver. Conclusion: Dark tea extracts are thought to have an anti-obesity effect by reducing the levels of the main transcription factors that promote adipocyte differentiation, such as C/EBPα, and PPARγ. Therefore, diet products using dark tea extracts could be developed.

Polyampholyte (PA) hydrogels have great potential for biomedical applications, owing to their high toughness and good self-recovery and self-healing (SELF) behavior in addition to their physical properties similar to human tissue. However, their implementation as practical biomedical skin patches or wearable devices has so far been limited by their insufficient transdermal adhesion strength. In this work, a new polyampholytic terpolymer (PAT) hydrogel with enhanced skin adhesion was developed using a novel and simple strategy that tunes the structure of ion-pair associations (IPAs), acting as cross-links, in the hydrogel via adding an extra neutral monomer component into the network without changing the total charge balance. The PAT hydrogels were synthesized by the terpolymerization of the neutral monomer N,N-dimethylacrylamide (DMAAm) (or 2-hydroxyethyl methacrylate (HEMA)) as well as the cationic monomer 3-(methacryloylamino) propyl-trimethylammonium chloride (MPTC) and the anionic monomer sodium p-styrenesulfonate (NaSS). Their IPA, which determines their network structure, was modulated by varying the feed concentration of the neutral monomer, Cnm. An increase of Cnm within an optimized Cnm window (0.3-0.4 M) decreased the cross-linking density (strength and density of the IPAs) of the PAT hydrogels, reducing the softening temperature and Young's modulus, which increased compliance but maintained sufficient mechanical strength and thereby maximized the contact surface and enhanced skin adhesion. The DMAAm monomers, compared to the HEMA monomers, produced the higher skin adhesion of the PAT hydrogel, which was explained by the difference in their reactivity to the MPTC and NaSS. This study demonstrated this new method to develop the PAT hydrogels with excellent skin adhesion and biocompatibility while maintaining good toughness, compliance, and SELF behavior and the potential of the PAT hydrogels for biomedical skin patches and wearable devices.

The prevalence of lumbosacral radiculopathy is estimated to be approximately 3% to 5% in patient populations. Lumbosacral radiculopathy is largely caused by a complex interaction between biomechanical and biochemical factors. Nerve block therapy (NBT) mainly treats lumbosacral radiculopathy by improving the biochemical factors, whereas acupotomy mainly focuses on improving the biomechanical factors. Therefore, it is thought that synergistic effects may be obtained for the treatment of lumbosacral radiculopathy when both NBT and acupotomy are combined. However, no study in China and Korea, where acupotomy is majorly provided, has reported the effects of such a combination treatment. Therefore, this study aimed to evaluate the safety, effectiveness, and cost-effectiveness of the concurrent use of a deeply inserted acupotomy and NBT for the treatment of lumbosacral radiculopathy.This is an open-label, parallel, assessor-blinded, randomized controlled trial, which will include 50 patients with lumbosacral radiculopathy. After patients voluntarily agree to participate in the study, they will be screened, and will undergo necessary examinations and tests according to the protocol. Those who satisfy the selection criteria will be randomly assigned to either the NBT + acupotomy or NBT groups in a 1:1 ratio. Both groups will undergo 2 NBTs once every 2 weeks from 1 week after the screening test. The treatment group will receive additional acupotomy twice a week for 4 weeks. The primary endpoint is the Oswestry Disability Index, whereas the secondary endpoints are the Numeral Rating Scale, European Quality of Life 5-dimension, McGill pain Questionnaire, Roland-Morris Disability Questionnaire, safety assessment, and economic feasibility evaluation. The measurements will be made at 0, 2, 4, and 8 weeks.This trial has received complete ethical approval from the Ethics Committee of Catholic Kwandong University International St. Mary's Hospital (IS20OISE0085). We intend to submit the results of the trial to a peer-reviewed journal and/or conferences.

This paper presents a new surface modification strategy to develop a poly(ethylene terephthalate) (PET)-based membrane having a hydrophilic surface, high nutrient ion permeability, sufficient mechanical strength, and organic fouling resistance, using an anthracene (ANT)-attached polyethylene glycol (PEG) surface modification agent (SMA) synthesized in this work. During the modification process, the ANT parts of the SMAs poke through and anchor to the surface of a commercial PET woven fabric via physical interactions and mechanical locking. The PEG chain parts coat the surface in the brush and arch forms, which generates a hydration layer on the fabric surface. The consequently obtained surface property and unique structure of the modified PET-based membrane result in higher nitrate ion permeability, organic fouling resistance, and microalgae production compared to those of the unmodified one. These are also affected by the molecular weight of the PEG and the number density of the anchored SMAs. The study demonstrates that this new surface modification method has the potential to allow the development of a desirable PET-based membrane for the efficient massive production of marine microalgae.

Three-dimensional (3D) porous materials gain considerable attention in electronics and biomedical/environmental engineering owing to their high porosity, large surface area, and controllable morphological and mechanical properties. In this work, reversibly compressible feather-like lightweight 3D chitosan/graphene oxide (CS/GO) composite foams were prepared with varying the composition ratios of CS to GO using a freeze-drying method. Their structure was obtained via amide linkage formation between the CS amine groups and GO carboxylic acid groups throughout the foam. Chemical analysis of the foams was performed using Fourier-transform infrared spectroscopy, and their morphology was analyzed by field-emission scanning electron microscopy and crosslinking density measurements. Their mechanical features and static and dynamic viscoelastic properties were characterized by monotonic compression, stress-relaxation, and frequency sweep tests using a custom-built micro-indenter and dynamic mechanical analyzer. With increasing the CS concentration, their storage/loss modulus and crosslinking density increased, while their tanδ decreased. Their viscoelastic properties predicted using the proposed modified micromechanics models agreed with the experimental data. This study demonstrates a simple strategy to produce lightweight porous 3D CS/GO composite foams with biocompatibility, electrical conductivity, and decent mechanical and viscoelastic properties regulated by the composition. These foams are promising materials applicable in biomedical and environmental engineering and electrical devices.

Graphene oxide (GO) attracts tremendous attention for application in high-performance stimuli-responsive “smart” materials because of its unique and excellent electrical, mechanical, thermal, and optical properties, high biocompatibility, and potential application in a variety of fields, including nanocomposite-based devices. Even at an extremely small loading, the chemical, physical, and mechanical properties of GO-polymer nanocomposites can be significantly changed due to its one-atom thickness and large surface area. Therefore, GO-based filler-containing polymer nanocomposites are sensitive to various external stimuli, such as electric and magnetic fields, pH, thermal or optical excitations, and stress. This article reviews the compositions, preparations, and characteristics of a variety of external stimuli-responsive nanocomposites containing GO and other graphene-based fillers. Particularly, the electrorheological and magnetorheological behaviors of smart fluids are described with well-known models and relationships. Finally, various applications of GO-polymer nanocomposites are briefly presented.

Supplemental Digital Content is available in the text, Background: Chemotherapy-induced peripheral neuropathy (CIPN) occurs in 68.1% of patients within the first month of undergoing chemotherapy; however, standardized treatment for CIPN has not been established yet. The efficacy of acupuncture, a widely used treatment for CIPN in South Korea, has not been studied sufficiently. This study aimed to review the studies that evaluated the efficacy of acupuncture or electroacupuncture (EA) in treating CIPN. Methods: A literature search was performed on relevant international databases — MEDLINE, Embase, the Allied and Complementary Medicine Databases, and China National Knowledge Infrastructure — as well as Korean databases — the National Digital Science Library, Oriental Medicine Advanced Searching Integrated System, DBpia, and Korean Studies Information Service System. Randomized controlled trials (RCTs) that aimed to treat CIPN symptoms with acupuncture or EA and set not only a control group with a conventional pharmacological treatment or injection, but also a placebo control or sham-acupuncture group, were included. Meta-analysis was conducted to elucidate the efficacy of acupuncture/EA on the basis of symptom score. Results: Of the 13 studies included in the literature review, 12 RCTs compared acupuncture and pharmacological treatments. There were 3 EA RCTs, but only 1 RCT compared EA and sham-EA. A total of 832 participants were included in these studies. Five RCTs showed that acupuncture was more effective than pharmacological treatment in terms of efficacy rate. Regarding the risk of bias summary, the quality of included studies was poor. Only 1 study compared the efficacy of EA and sham EA; therefore, the specific efficacy of acupuncture could not be elucidated. Conclusion: Acupuncture is safe, but the symptom-alleviating effect on CIPN can hardly be determined because of methodological deficiencies of the included studies. In terms of the clinical efficacy rate, acupuncture was more effective than conventional pharmacological treatments. PROSPERO registration number: CRD42018111509.

The purpose of this study was to investigate and compare the clinical and radiological results of ORIF with inter-fragment screw or buttress plate fixation of acute PIP joint fracture dorsal dislocation. Between January 2007 to December 2016, nineteen patients - 14 men and 5 women with an average age of 40.9 (19 to 64) years - were included in this study; 9 patients underwent small sized interfragmentary screw fixation and 10 patients underwent small buttress plating. The average follow-up period was 45.1 (13 to 78) months. Clinical assessment included measurement of range of motion (ROM) of the proximal and distal interphalangeal joint (PIP, DIP), grip and pinch strength, and pain with use of the Visual Analog Scale (VAS). At the postoperative X-ray, articular step off, gap, and degree of dorsal subluxation was measured, and maintenance of the reduction, fracture union, and the presence of degenerative changes were assessed. All patients achieved solid unions without instability. The overall average range of motion of PIP joint were from 9° to 85° (10-83° in the screw group, 8-87° in the plate group without significant difference). However, the screw group (average: 53°) presented more flexion in the distal interphalangeal joint than the plate group (average: 34°). Plate fixation can cause limited DIP flexion. Six of the ten patients from the plate group, underwent implant removal and two of these patients required PIP joint arthrolysis due to the PIP flexion contracture of more than 30°. Three of the nine patients in screw group underwent implant removal and two of the three patients required PIP joint arthrolysis. Mini plate and screw fixation of acute PIP joint fracture dorsal dislocation can achieve comparable favorable clinical and radiographic outcomes through stable fixation and early range of motion exercise. Screw fixation, if possible, is probably preferable to plate fixation because of better DIP joint ROM and lower incidence of hardware removal. If there is a need for plate fixation the use of a short plate is recommended to avoid joint stiffness.ZIEL: In dieser Studie wurden die klinischen und radiologischen Ergebnisse nach Schraubenosteosynthesen mit den Ergebnissen von Plattenosteosynthesen von dorsalen Luxationsfrakturen des Fingermittelgelenkes (PIP-Gelenk) verglichen. Zwischen Januar 2007 und Dezember 2016 wurden 19 Patienten – 14 Männer und 5 Frauen mit einem durchschnittlichen Alter von 40,9 (19–64) Jahren in die Studie eingeschlossen. Bei 9 Patienten erfolgte eine Schrauben-, bei 10 Patienten eine Plattenosteosynthese. Die Nachuntersuchungszeit betrug im Schnitt 45,1 (13 bis 78) Monate. Die klinische Untersuchung umfasste die Messung des Bewegungsumfangs des Mittel- und Endgelenkes (PIP- und DIP-Gelenk), der Grobgriff- und Spitzgriffkraft sowie der Schmerzen mittels visuellen Analogskala (VAS). Die postoperativen Röntgenbildern wurde bzgl. Frakturheilung, Repositionsverlust, degenerativen Veränderungen und der Größe verbliebener Stufen- und Spaltbildungen ausgewertet. Bei allen Patienten kam es zur knöchernen Heilung ohne Zeichen einer Instabilität des PIP-Gelenkes. Die durchschnittliche Beweglichkeit aller PIP-Gelenke betrug 0–9–85°, für die Schraubengruppe 0–10–83°und für die Plattengruppe 0–8–87°, ohne dass ein signifikanter Unterschied bestand. Im DIP-Gelenk wiesen Patienten der Schraubengruppe eine bessere Flexion auf. Bei 6 der 10 Patienten mit Plattenosteosynthese musste die Platte entfernt werden, gleichzeitig erfolgte bei 2 eine Lösung des PIP-Gelenkes aufgrund einer Beugekontraktur von mehr als 30°. Bei 3 der 9 Patienten mit Schraubenosteosynthese erfolgte ebenfalls die Entfernung des Osteosynthesematerials, 2 erhielten zusätzlich eine Lösung des PIP-Gelenkes. Schrauben- und Plattenosteosynthesen dorsaler Mittelgelenksluxationsfrakturen erzielen vergleichbar gute klinische und radiologische Ergebnisse und erlauben eine Frühmobilisation bei stabiler Situation. Aufgrund der besseren Beweglichkeit im DIP-Gelenk und da weniger häufig das Osteosynthesematerial entfernt werden muss, ist – wenn möglich – die Schraubenosteosynthese zu bevorzugen. Bedarf es einer Plattenosteosynthese, sollte die Platte möglichst kurz sein, um Bewegungseinschränkungen des DIP-Gelenkes zu vermeiden.

Background: Amphilimus-eluting stent (AES) is a novel polymer-free drug eluting stent that combines sirolimus with fatty acid as antiproliferative drug and has shown promising results in percutaneous coronary intervention.We evaluated the clinical safety and efficacy of AES in an all-comers South-East Asian registry. Methods: Between May 2014 to April 2017, 268 patients (88% male, mean age 60.1 ± 10.8 years) with 291 coronary lesions were treated with AES. The primary endpoint was major adverse cardiac events (MACE) ie a composite of cardiovascular mortality, myocardial infarction (MI) and target lesion revascularization (TLR) at 12-month follow-up. Results: The majority of patients presented with acute coronary syndrome (75%) and 75% had multi-vessel disease on angiography. Diabetes mellitus was present in 123 patients (46%). The most common target vessel for PCI was left anterior descending artery (43%) followed by right coronary artery (36%), left circumflex (10%) and left main (6%).The majority of lesions were type B-C (85%) by ACC/AHA lesion classification. An average of 1.25 ± 0.5 AES were used per patient, with mean AES diameter of 3.1 ± 0.4 mm and average total length of 34.8 ± 19.4 mm.At 12-month follow-up, 4% of patients developed MACE. MACE was mainly driven by cardiovascular mortality (1.5%), MI (2%) and TLR (1.5%). The rate of stent thrombosis was 1.5%. Conclusion: In a contemporary all-comers South-East Asian registry with high rate of diabetes mellitus, AES was found to be efficacious with a low incidence of MACE observed at 12-month follow-up. Keywords: Amphilimus, Drug-eluting stent, Outcomes, Percutaneous coronary intervention, South-East Asia

Introduction: Chemotherapy-induced peripheral neuropathy (CIPN) is one of the major side effects of chemotherapy. Its main symptoms are pain, paresthesia, and numbness. However, the mechanisms underlying the development of CIPN remain unclear and standard treatments have not been established. Recently, there has been a growing interest in various approaches to overcome the limitations of the existing treatments. This study aims to evaluate the efficacy and safety of the concurrent use of two complementary and alternative therapies: electroacupuncture (EA) and Chuna manual therapy (CMT), with pregabalin, which is the conventional pharmacotherapy for neuropathic pain. Methods/design: This is an open-label, parallel, assessor-blinded randomized controlled trial, which includes 90 patients with colorectal and breast cancer, who developed CIPN. After a 2-week preparation period, the patients are divided into three groups (pregabalin administration group, pregabalin + EA treatment group, and pregabalin + CMT treatment group), treated for approximately 5 weeks and followed-up 4 weeks after treatment. The primary outcome is assessed using the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group Neurotoxicity subscale score (version 4.0) and the secondary outcome is measured using the Quality of Life Questionnaire-CIPN 20-Item Scale (version 3.0) and the quality of life questionnaire (version 3.0) developed by the European Organisation for Research and Treatment of Cancer. Moreover, exploratory efficacy and safety evaluations will be conducted based on the chemotherapy-completion rate and nerve conduction studies.

Background Injectable hydrogels have been extensively researched for the use as scaffolds or as carriers of therapeutic agents such as drugs, cells, proteins, and bioactive molecules in the treatment of diseases and cancers and the repair and regeneration of tissues. It is because they have the injectability with minimal invasiveness and usability for irregularly shaped sites, in addition to typical advantages of conventional hydrogels such as biocompatibility, permeability to oxygen and nutrient, properties similar to the characteristics of the native extracellular matrix, and porous structure allowing therapeutic agents to be loaded. Main body In this article, recent studies of injectable hydrogel systems applicable for therapeutic agent delivery, disease/cancer therapy, and tissue engineering have reviewed in terms of the various factors physically and chemically contributing to sol-gel transition via which gels have been formed. The various factors are as follows: several different non-covalent interactions resulting in physical crosslinking (the electrostatic interactions (e.g., the ionic and hydrogen bonds), hydrophobic interactions, π-interactions, and van der Waals forces), in-situ chemical reactions inducing chemical crosslinking (the Diels Alder click reactions, Michael reactions, Schiff base reactions, or enzyme-or photo-mediated reactions), and external stimuli (temperatures, pHs, lights, electric/magnetic fields, ultrasounds, or biomolecular species (e.g., enzyme)). Finally, their applications with accompanying therapeutic agents and notable properties used were reviewed as well. Conclusion Injectable hydrogels, of which network morphology and properties could be tuned, have shown to control the load and release of therapeutic agents, consequently producing significant therapeutic efficacy. Accordingly, they are believed to be successful and promising biomaterials as scaffolds and carriers of therapeutic agents for disease and cancer therapy and tissue engineering.

Polycarboxylates in chemical admixtures are adsorbed onto the surface of cement particle, and the degree of their adsorption is related to the performance of concrete. Measuring total organic carbon (TOC), we demonstrated the amount of the consumed carbon is consistent regardless of the existence of aggregates. This result allows us to consider the effect of aggregates inclusion in a superplasticized cement paste. In a multiscale approach, concrete or mortar is considered as suspension of aggregates in cement paste. Excess paste layer covering aggregates in cement-based materials is considered taking a material property of the layer thickness in addition to the volume fraction of the aggregates. Finally, the yield stress of mortar or concrete can be predicted assuming that the layer thickness is constant regardless of the aggregate volume fraction.

The use of injectable hydrogel formulations have been suggested as a promising strategy for the treatment of degenerative disc disease to both restore the biomechanical function and reduce low back pain. In this work, a new thermo-sensitive injectable hydrogels with tunable thermo-sensitivity and enhanced stability were developed with N-hexanoylation of glycol chitosan (GC) for treatment of degenerative disc disease, and their physico-chemical and biological properties were evaluated. The sol-gel transition temperature of the hydrogels was controlled in a range of 23–56 °С, depending on the degree of hexanoylation and the polymer concentration. In vitro and in vivo tests showed no cytotoxicity and no adverse effects in a rat model. The hydrogel filling of the defective IVD site in an ex vivo porcine model maintained its stability for longer than 28 days. These results suggest that the hydrogel can be used as an alternative material for treatment of disc herniation.