156 research outputs found

    Wetting Behavior of Dental Implants

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    Titanium (Ti) and titanium alloys are widely used in biomedical devices and components, because of their desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, corrosion resistance, and biocompatibility. However, Ti and its alloys cannot meet all of the clinical requirements. Therefore, surface modiļ¬cation of Ti has been often performed to improve the biological, chemical, and mechanical properties. Various modiļ¬cations of surface properties have been investigated to predictably improve the osseointegration of Ti implants. The rate and quality of osseointegration in Ti implants are related to their surface properties. A multiplicity of implant surface forms exist engineered with mechanical features that physically interlock the implant with bone. Various strategies have been utilized to improve bone integration of Ti-based implants. For example, surface grit blasting, acid-etching and anodization methods enhance cell growth, improving implant ļ¬xation through increases in interlocking surface area and alterations of oxide thickness. On the other hand, surface composition and hydrophilicity are parameters that may play a role in implant-tissue interaction and osseointegration. Highly hydrophilic surfaces seem more desirable than hydrophobic ones in view of their interactions with biological ļ¬‚uids, cells and tissues. Several recent studies have shown that the surface energy of biomaterials strongly has inļ¬‚uence the initial cell attachment and spreading of osteoblastic cells on the biomaterial surfaces. Hallab et al. said that surface energy might be a more important determinant of cell adhesion and proliferation, and might be more useful than surface roughness for generating cell adhesion and cell. It may have the inļ¬‚uence on protein adsorption and the structural rearrangement of the proteins on the material. Therefore, understanding the relationship between surface energy and cell adhesion on different biomaterials will facilitate the design of optimized implant material surfaces and subsequently the cell attachment. Surface energy is an important parameter of the material surface. It is affected by several surface characteristics, such as chemical composition, surface charge, and microstructural topography. Many papers reported that surface energy is one of important surface characteristics parameter of modified titanium surfaces. Given the importance of surface wettability of dental implants surfaces in the achievement of osseointegration, the surface free energy values for a given material, obtained by various methods and with use of different measuring liquids, are not consistent. Thus, we provided a review article of the surface modification on titanium surface and the surface wettability. The relationship between CAs and surface preparations was determined in this review

    Antioxidant capacities and polyphenolics of Chinese cabbage (Brassica rapa L. ssp. Pekinensis) leaves

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    a b s t r a c t Chinese cabbage (Brassica rapa L. ssp. Pekinensis) is a green leafy vegetable used mainly in kimchi, salted and fermented dishes. Consumer preference for the leaf portion differs according to the type of dishes. In this study, Chinese cabbage was divided into three parts, and their antioxidant activities were investigated through in vitro assays. The total phenolic contents (TPC), total flavonoid contents (TFC), and vitamin C contents were also determined as indicators of antioxidant contents. The phenolic acids and flavonoids were separated and identified using high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). The outer leaf had the strongest antioxidant activity with the maximum antioxidant contents, followed by the mid-and inner leaves. Principal component analysis (PCA) revealed that outer leaf is positively related to caffeic acid, p-coumaric acid, ferulic acid, and myricetin contents, whereas the mid-and inner leaves are negatively related to sinapic acid contents

    Fabrication of a Micro-Fluid Gathering Tool for the Gastrointestinal Juice Sampling Function of a Versatile Capsular Endoscope

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    This paper presents a micro-fluid gathering tool for a versatile capsular endoscope that employs a solid chemical propellant, azobisisobutyronitrile (AIBN). The proposed tool consists of a micro-heater, an AIBN matrix, a Venturi tube, a reservoir, an inlet, and an outlet. The micro-heater heats the AIBN matrix to be decomposed into by-products and nitrogen gas. This nitrogen gas generates negative pressure passing through the Venturi tube. The generated negative pressure inhales a target fluid from around the inlet into the reservoir. All the parts are designed to be embedded inside a cylindrical shape with a diameter of 17 mm and a height of 2.3 mm in order to integrate it into a versatile developmental capsular endoscope without any scaledown. Two sets of the proposed tools are fabricated and tested: one is made of polydimethylsiloxane (PDMS) and the other is made of polymethylmethacrylate (PMMA). In performance comparisons, the PDMS gathering tool can withstand a stronger pulling force, and the PMMA gathering tool requires a less negative pressure for inhaling the same target fluid. Due to the instant and full activation of the thin AIBN matrix, both types of gathering tool show analogous performance in the sample gathering evaluation. The gathered volume is approximately 1.57 Ī¼L using approximately 25.4 Ī¼L of AIBN compound

    Long-Term Effect of Rigid Foot Orthosis in Children Older Than Six Years With Flexible Flat Foot

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    Objective To evaluate the long-term effect of a custom-made rigid foot orthosis (RFO) in children older than 6 years with pes planus (flat foot). Methods Medical records of 42 children diagnosed with flexible pes planus who were fitted with RFOs based on the inverted technique and underwent more than four consecutive radiological studies were reviewed. Resting calcaneal stance position (RCSP), anteroposterior talocalcaneal angle, lateral talocalcaneal angle, lateral talometatarsal angle, and calcaneal pitch were initially measured in both feet to evaluate alignment. Followup clinical and radiological evaluations were then performed at 12ā€“18, 24ā€“30, 36ā€“42, and ā‰„48 months after RFO application. Repeated measures analysis of variance was used to evaluate significant differences. Results Significant improvements in all radiological indicators and significant progression of RCSP toward the corrective direction were observed after RFO application relative to baseline measurements. Conclusion According to our findings, RFO can induce significant improvements in calcaneus-related radiographic indices and subsequently improve talus-related radiologic indices

    Barrier protection via Toll-like receptor 2 signaling in porcine intestinal epithelial cells damaged by deoxynivalnol

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    Additional file 2. IPEC-J2 cells pretreated with TLR2 ligand maintained the expression of MCP-1, GM-CSF and TLR2 against DON exposure. IPEC-J2 cells pretreated with or without TLR2 ligand for 24Ā h were exposed to DON. (A) The bar graph showed the mRNA levels of porcine mcp-1, gm-csf measured using real time-PCR at 1 and 6Ā h after DON exposure (nĀ =Ā 3). (B) The mRNA levels of porcine tlr2 were measured using real-time quantitative PCR analysis at 6Ā h. NT represents no treatment. Expression of each mRNA was presented relative to the expression of housekeeping gene, gapdh (nĀ =Ā 3). *PĀ <Ā 0.05; **PĀ <Ā 0.01; ***PĀ <Ā 0.001, determined by one-way ANOVA with Tukeyā€™s posttest

    Transnasal targeted delivery of therapeutics in central nervous system diseases: a narrative review

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    Currently, neurointervention, surgery, medication, and central nervous system (CNS) stimulation are the main treatments used in CNS diseases. These approaches are used to overcome the blood brain barrier (BBB), but they have limitations that necessitate the development of targeted delivery methods. Thus, recent research has focused on spatiotemporally direct and indirect targeted delivery methods because they decrease the effect on nontarget cells, thus minimizing side effects and increasing the patientā€™s quality of life. Methods that enable therapeutics to be directly passed through the BBB to facilitate delivery to target cells include the use of nanomedicine (nanoparticles and extracellular vesicles), and magnetic field-mediated delivery. Nanoparticles are divided into organic, inorganic types depending on their outer shell composition. Extracellular vesicles consist of apoptotic bodies, microvesicles, and exosomes. Magnetic field-mediated delivery methods include magnetic field-mediated passive/actively-assisted navigation, magnetotactic bacteria, magnetic resonance navigation, and magnetic nanobotsā€”in developmental chronological order of when they were developed. Indirect methods increase the BBB permeability, allowing therapeutics to reach the CNS, and include chemical delivery and mechanical delivery (focused ultrasound and LASER therapy). Chemical methods (chemical permeation enhancers) include mannitol, a prevalent BBB permeabilizer, and other chemicalsā€”bradykinin and 1-O-pentylglycerolā€”to resolve the limitations of mannitol. Focused ultrasound is in either high intensity or low intensity. LASER therapies includes three types: laser interstitial therapy, photodynamic therapy, and photobiomodulation therapy. The combination of direct and indirect methods is not as common as their individual use but represents an area for further research in the field. This review aims to analyze the advantages and disadvantages of these methods, describe the combined use of direct and indirect deliveries, and provide the future prospects of each targeted delivery method. We conclude that the most promising method is the nose-to-CNS delivery of hybrid nanomedicine, multiple combination of organic, inorganic nanoparticles and exosomes, via magnetic resonance navigation following preconditioning treatment with photobiomodulation therapy or focused ultrasound in low intensity as a strategy for differentiating this review from others on targeted CNS delivery; however, additional studies are needed to demonstrate the application of this approach in more complex in vivo pathways
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