• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5281-5286
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• 2012

Purpose: Receptor 7 (CXCR7) has recently been characterized as a novel receptor for CXCL12/SDF-1 (stromal cell derived factor-1). Given the demonstrated importance of CXCL12/SDF-1 in angiogenesis and tumour metastasis, we hypothesized that CXCR7 may also play a role in tumour pathogenesis. Located in the limited space of the intracranial cavity, any brain tumours can be inherently serious and life-threatening. However, the expression of CXCR7 in pituitary adenoma, neurilemmoma or hemangioblastoma remains to be elucidated. Therefore, we aimed to determine the potential contribution of CXCR7 in the development of brain tumours. Methods: In this study we examined and quantified the mRNA expression of CXCR7 in four different human brain tumours - 27 patients with neurilemmoma (8 patients), pituitary adenoma (7 patients), hemangioblastoma (6 patients), or meningioma (6 patients) undergoing surgical resection in the West China Hospital of Sichuan University. There were 15 females and 12 males aged from 28 to 70 years old. Total RNA was isolated and mRNA was measured by quantitative real-time RT-PCR. One-way analysis of variance (ANOVA) was performed using SPSS 11.0 statistical software to compare the mRNA levels of CXCR7 among four groups. Results: We found that CXCR7 mRNA was detected in all tumour samples. Quantitative results showed that the levels of CXCR7 mRNA in brain tissues from patients with neurilemmoma or meningioma were significantly higher than those with pituitary adenoma or hemangioblastoma. Conclusions: The results suggest that the CXCR7 may play a role in progression, metastasis and angiogenesis of brain tumours.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.677-682
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• 2014

Resveratrol has been examined in several model systems for potential effects against cancer. Adenosine monophosphate-activated protein kinase (AMPK) is reported to suppress proliferation in most eukaryocyte cells. Whether resveratrol via AMPK inhibits proliferation of oesophageal adenocarcinoma cells (OAC) is unknown. The aim of this study was to determine the roles of AMPK in the protective effects of resveratrol in OAC proliferation and to elucidate the underlying mechanisms. Treatment of cultured OAC derived from human subjects or cell lines with resveratrol resulted in decreased cell proliferation. Further, inhibition of AMPK by pharmacological reagent or genetical approach abolished resveratrol-suppressed OAC proliferation, reduced the level of $p27^{Kip1}$, a cyclin-dependent kinase inhibitor, and increased the levels of S-phase kinase-associated protein 2 (Skp2) of $p27^{Kip1}$-E3 ubiquitin ligase and 26S proteasome activity reduced by resveratrol. Furthermore, gene silencing of $p27^{Kip1}$ reversed resveratrol-suppressed OAC proliferation. In conclusion, these findings indicate that resveratrol inhibits Skp2-mediated ubiquitylation and 26S proteasome-dependent degradation of $p27^{Kip1}$ via AMPK activation to suppress OAC proliferation.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1299-1306
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• 2015

This study aims to investigate the mechanism of action of the cinnamon bark essential oil (CB), when used singly and also in combination with piperacillin, for its antimicrobial and synergistic activity against beta-lactamase TEM-1 plasmid-conferred Escherichia coli J53 R1. Viable count of bacteria for this combination of essential oil and antibiotic showed a complete killing profile at 20 h and further confirmed its synergistic effect by reducing the bacteria cell numbers. Analysis on the stability of treated cultures for cell membrane permeability by CB when tested against sodium dodecyl sulfate revealed that the bacterial cell membrane was disrupted by the essential oil. Scanning electron microscopy observation and bacterial surface charge measurement also revealed that CB causes irreversible membrane damage and reduces the bacterial surface charge. In addition, bioluminescence expression of Escherichia coli [pSB1075] and E. coli [pSB401] by CB showed reduction, indicating the possibility of the presence of quorum sensing (QS) inhibitors. Gas-chromatography and mass spectrometry of the essential oil of Cinnamomum verum showed that trans-cinnamaldehyde (72.81%), benzyl alcohol (12.5%), and eugenol (6.57%) were the major components in the essential oil. From this study, CB has the potential to reverse E. coli J53 R1 resistance to piperacillin through two pathways; modification in the permeability of the outer membrane or bacterial QS inhibition.

• Corrosion Science and Technology
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• v.18 no.5
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• pp.212-219
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• 2019

This paper reviews recent approaches to develop composite polymer-containing coatings by plasma electrolytic oxidation (PEO) using various low-molecular fractions of superdispersed polytetrafluoroethylene (SPTFE). The features of the unique approaches to form the composite polymer-containing coating on the surface of MA8 magnesium alloy were summarized. Improvement in the corrosion and tribological behavior of the polymer-containing coating can be attributed to the morphology and insulating properties of the surface layers and solid lubrication effect of the SPTFE particles. Such multifunctional coatings have high corrosion resistance ($R_p=3.0{\times}10^7{\Omega}cm^2$) and low friction coefficient (0.13) under dry wear conditions. The effect of dispersity and ${\xi}$-potential of the nanoscale materials ($ZrO_2$ and $SiO_2$) used as electrolyte components for the plasma electrolytic oxidation on the composition and properties of the coatings was investigated. Improvement in the protective properties of the coatings with the incorporated nanoparticles was explained by the greater thickness of the protective layer, relatively low porosity, and the presence of narrow non-through pores. The impedance modulus measured at low frequency for the zirconia-containing layer (${\mid}Z{\mid}_{f=0.01Hz}=1.8{\times}10^6{\Omega}{\cdot}cm^2$) was more than one order of magnitude higher than that of the PEO-coating formed in the nanoparticles-free electrolyte (${\mid}Z{\mid}_{f=0.01Hz}=5.4{\times}10^4{\Omega}{\cdot}cm^2$).

• Advances in nano research
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• v.13 no.1
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• pp.87-96
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• 2022

Drug self-delivery systems can easily realize combination drug therapy and avoid carrier-induced toxicity and immunogenicity because they do not need non-therapeutic carrier materials. So, designing appropriate drug self-delivery systems for specific diseases can settle most of the problems existing in traditional drug delivery systems. Retinal pigment epithelium is very important for the homeostasis of retina. However, it is vulnerable to oxidative damage and difficult to repair. Worse still, the antioxidants can hardly reach the retina by non-invasive administration routes due to the ocular barriers. Herein, the targeted group (folic acid) and antioxidant (melatonin) have been grafted on the surface of ZnO quantum dots to fabricate a new kind of drug self-delivery systems as a protectant via eyedrops. In this study, the negative nanoparticles with size ranging in 4~6 nm were successfully synthesized. They could easily and precisely deliver drugs to retinal pigment epithelium via eyedrops. And they realized acid degradation to controlled release of melatonin and zinc in retinal pigment epithelium cells. Consequently, the structure of retinal pigment epithelium cells were stabilized according to the expression of ZO-1 and β-catenin. Moreover, the antioxidant capacity of retinal pigment epithelium were enhanced both in health mice and photic injury mice. Therefore, such new drug self-delivery systems have great potential both in prevention and treatment of oxidative damage induced retinal diseases.

• Smart Structures and Systems
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• v.29 no.2
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• pp.375-387
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• 2022

One of the latest teaching strategies is smart classroom teaching. Teaching is carried out with the assistance of smart teaching technologies to improve teacher-student contact, increase students' learning autonomy, and give fresh ideas for the fulfillment of students' deep learning. Computer-based technology has improved students' language learning and significantly motivating them to continue learning while also stimulating their creativity and enthusiasm. However, the difficulties and barriers that many EFL instructors are faced on seeking to integrate information and communication technology (ICT) into their instruction have raised discussions and concerns regarding ICT's real worth in the language classroom. This is a case study that includes observations in the classroom, field notes, interviews, and written materials. In EFL classrooms, both computer-based and non-computer-based activities were recorded and analyzed. The main instrument in this study was a survey questionnaire comprising 43 items, which was used to examine the efficiency of ICT integration in teaching and learning in public schools in Kuala Lumpur. A total of 101 questionnaires were delivered, while each responder being requested to read the statements provided. The total number of respondents for this study was 101 teachers from Kuala Lumpur's public secondary schools. The questionnaire was randomly distributed to respondents with a teaching background. This study indicated the accuracy of utilizing Teaching-Learning-Based Optimization (TLBO) in analyzing the survey results and potential for students to learn English as a foreign language using computers. Also, the usage of foreign language may be improved if real computer-based activities are introduced into the lesson.

• Clean Technology
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• v.28 no.2
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• pp.97-102
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• 2022

Lithium sulfur (Li-S) batteries have attracted considerable attention as a promising candidate for next-generation power sources due to their high theoretical energy density, low cost, and eco-friendliness. However, the poor electrical conductivity of sulfur and its insoluble discharging products (Li₂S₂/Li₂S), large volume changes, severe self-discharge, and dissolution of lithium polysulfide intermediates result in rapid capacity fading, low Coulombic efficiency, and safety risks, hindering Li-S battery commercial development. In this study, a three-dimensionally (3D) connected hierarchical porous carbon framework (HPCF) derived from waste sunflower seed shells was synthesized as a sulfur host for Li-S batteries via a chemical activation method. The natural 3D connected structure of the HPCF, originating from the raw material, can effectively enhance the conductivity and accessibility of the electrolyte, accelerating the Li⁺/electron transfer. Additionally, the generated micropores of the HPCF, originated from the chemical activation process, can prevent polysulfide dissolution due to the limited space, thereby improving the electrochemical performance and cycling stability. The HPCF/S cell shows a superior capacity retention of 540 mA h g^-1 after 70 cycles at 0.1 C, and an excellent cycling stability at 2 C for 700 cycles. This study provides a potential biomass-derived material for low-cost long-life Li-S batteries.

• Fashion & Textile Research Journal
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• v.25 no.2
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• pp.221-229
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• 2023

This study aims to develop knee protectors that provide high safety and fitness, while incorporating a motion-adaptable 3D-printed pad. These protectors were evaluated by individuals who experience knee discomfort or pain. The results are as follows. First, the 3Dprinted pad design of a hexagonal mesh structure, which is modeled for excellent appearance and knee movement. Each unit of the mesh has a outer layer of 2mm thick, a spacer layer of 1 mm in diameter, and is connected by a 1.5 mm bridge. The bridge was extended up to 1.2 cm. Second, the knee brace was designed in three types - cylinder, strap, and combination by Universal design. Impact protection measurements of the three knee protectors demonstrated roughly 80% reduction in impact. Third, based on usability evaluation, cylinder type protectors have the highest ratings in most areas, primarily because of their ease of use. The strap type protector received positive reviews in terms of appearance and care, and the combination type provided stable knee protection. This study demonstrated the potential industrial application of 3D printing technology by designing and evaluating protective products for the human body. The results of this study are expected to aid knee protector manufacturers in developing practical products and promoting the development of protective equipment for other body parts or purposes.

• Steel and Composite Structures
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• v.49 no.5
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• pp.487-502
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• 2023

In the realm of nanotechnology, the nonlocal strain gradient theory takes center stage as it scrutinizes the behavior of spinning cantilever nanobeams and nanotubes, pivotal components supporting various mechanical movements in sport structures. The dynamics of these structures have sparked debates within the scientific community, with some contending that nonlocal cantilever models fail to predict dynamic softening, while others propose that they can indeed exhibit stiffness softening characteristics. To address these disparities, this paper investigates the dynamic response of a nonlocal cantilever cylindrical beam under the influence of external discontinuous dynamic loads. The study employs four distinct models: the Euler-Bernoulli beam model, Timoshenko beam model, higher-order beam model, and a novel higher-order tube model. These models account for the effects of functionally graded materials (FGMs) in the radial tube direction, giving rise to nanotubes with varying properties. The Hamilton principle is employed to formulate the governing differential equations and precise boundary conditions. These equations are subsequently solved using the generalized differential quadrature element technique (GDQEM). This research not only advances our understanding of the dynamic behavior of nanotubes but also reveals the intriguing phenomena of both hardening and softening in the nonlocal parameter within cantilever nanostructures. Moreover, the findings hold promise for practical applications, including drug delivery, where the controlled vibrations of nanotubes can enhance the precision and efficiency of medication transport within the human body. By exploring the multifaceted characteristics of nanotubes, this study not only contributes to the design and manufacturing of rotating nanostructures but also offers insights into their potential role in revolutionizing drug delivery systems.

• Food Science of Animal Resources
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• v.44 no.4
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• pp.817-831
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• 2024

In this study, physicochemical and antioxidant properties, and storage stability (1, 3, and 7 days) of pork patties added with edible insect powders (EIP) of four species (Larvae of Tenenbrio molitor, Protaetia brevitarsis seulensis, Allomyrina dichotoma, and Gryllus bimaculatus) as meat partial substitutes were investigated. Twenty percent of each EIP was added to pork patties, and four treatments were prepared. On the other hand, two control groups were set, one with 0.1 g of ascorbic acid and the other without anything. Adding EIP decreased water content but increased protein, fat, carbohydrate, and ash contents. In addition, the use of EIP increased the water holding capacity and texture properties as well as decreased the cooking loss. However, the sensory evaluation and storage stability were negatively affected by the addition of EIP. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity had a positive effect on storage stability. It is believed that the addition of EIP resulted in high antioxidants due to the presence of polyphenol compounds in EIP. These results indicate that EIP has great potential to be used as meat partial substitute to improve the quality improvement and antioxidant in pork patties. However, in order to improve storage stability and consumer preference, further research is needed to apply it to patties by reducing the amount of EIP or adding auxiliary ingredients.