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Magnetic fluids are the suspensions composed of magnetic nanoparticles, surfactants, and non-magnetic carrier liquids. Magnetic fluids are widely used in various fields, especially in sealing, because of their excellent features, including rapid magnetic response, flexible flow ability, tunable magneto-viscous effect, and reliable self-repairing capability. Here, we provide an in-depth, comprehensive insight into the theoretical analyses and diverse applications of magnetic fluids in sealing from three categories: static sealing, rotary sealing, and reciprocating sealing. We summarize the magnetic fluid sealing mechanisms and the development of magnetic fluid seals from 1960s to the present, particularly focusing on the recent progress of magnetic fluid seals. Although magnetic fluid sealing technology has been commercialized and industrialized, many difficulties still exist in its applications. At the end of the review, the present challenges and future prospects in the progress of magnetic fluid seals are also outlined. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) methyltransferase-like 3 (METTL3) has been confirmed to be involved in multiple myeloma (MM) progression, and basic leucine zipper and W2 domains 2 (BZW2) is considered to be a regulator for MM development. However, whether METTL3 mediates MM progression by regulating BZW2 remains unclear. The messenger RNA (mRNA) and protein levels of METTL3 and BZW2 in MM specimens and cells were determined using quantitative real-time PCR and western blot analysis. Cell proliferation and apoptosis were assessed by cell counting kit 8 assay, 5-ethynyl-2′-deoxyuridine assay, colony formation assay, and flow cytometry. Methylated RNA immunoprecipitation-qPCR was used to detect the m6A modification level of BZW2. Xenograft tumor models were constructed to confirm the effect of METTL3 knockdown on MM tumor growth in vivo. Our results showed that BZW2 was upregulated in MM bone marrow specimens and cells. BZW2 downregulation reduced MM cell proliferation and promoted apoptosis, while its overexpression enhanced MM cell proliferation and inhibited apoptosis. METTL3 was highly expressed in MM bone marrow specimens, and its expression was positively correlated with BZW2 expression. BZW2 expression was positively regulated by METTL3. Mechanistically, METTL3 could upregulate BZW2 expression by modulating its m6A modification. Additionally, METTL3 accelerated MM cell proliferation and restrained apoptosis via increasing BZW2 expression. In vivo experiments showed that METTL3 knockdown reduced MM tumor growth by decreasing BZW2 expression. In conclusion, these data indicated that METTL3-mediated the m6A methylation of BZW2 to promote MM progression, suggesting a novel therapeutic target for MM. [ABSTRACT FROM AUTHOR]

Ferrofluids are a type of nanometer-scale functional material with fluidity and superparamagnetism. They are composed of ferromagnetic particles, surfactants, and base liquids. The main characteristics of ferrofluids include magnetization, the magnetoviscous effect, and levitation characteristics. There are many mature commercial ferrofluid damping applications based on these characteristics that are widely used in numerous fields. Furthermore, some ferrofluid damping studies such as those related to vibration energy harvesters and biomedical devices are still in the laboratory stage. This review paper summarizes typical ferrofluid dampers and energy harvesting systems from the 1960s to the present, including ferrofluid viscous dampers, ferrofluid inertia dampers, tuned magnetic fluid dampers (TMFDs), and vibration energy harvesters. In particular, it focuses on TMFDs and vibration energy harvesters because they have been the hottest research topics in the ferrofluid damping field in recent years. This review also proposes a novel magnetic fluid damper that achieves energy conversion and improves the efficiency of vibration attenuation. Finally, we discuss the potential challenges and development of ferrofluid damping in future research. [ABSTRACT FROM AUTHOR]

Current research on spherical parallel mechanisms (SPMs) mainly focus on surgical robots, exoskeleton robots, entertainment equipment, and other fields. However, compared with the SPM, the structure types and research contents of the SPM are not abundant enough. In this paper, a novel two-degree-of-freedom (2DOF) SPM with symmetrical structure is proposed and analyzed. First, the models of forward kinematics and inverse kinematics are established based on D-H parameters, and the Jacobian matrix of the mechanism is obtained and verified. Second, the workspace of the mechanism is obtained according to inverse kinematics and link interference conditions. Next, rotational characteristics analysis shows that the end effector can achieve continuous rotation about an axis located in the mid-plane and passing through the rotation center of the mechanism. Moreover, the rotational characteristics of the mechanism are proved, and motion planning is carried out. A numerical example is given to verify the kinematics analysis and motion planning. Finally, some variant mechanisms can be synthesized. This work lays the foundation for the motion control and practical application of this 2DOF SPM. [ABSTRACT FROM AUTHOR]

Background: Clonorchis sinensis was a food-borne zoonotic parasite in the worldwide and also an important risk factor of hepatic fibrosis. Excretory/secretion products of C. sinensis (CsESPs) are involved in parasite-host interactions and contribute to the development of hepatic damage. The aim of the present study was to investigate whether CsESPs and CsTP (adult protein) could induce autophagy of hepatic stellate cells (HSCs) and further activate HSCs so as to participate in the pathogenesis of hepatic fibrosis. Methods and results: The human hepatic stellate cell line LX-2 was stimulated by CsESPs and CsTP. CsESPs showed the effect on cell proliferation in methyl thiazolyl tetrazolium (MTT) assay while CsTP failed. Autophagosomes and autolysosomes were observed after the transmission mRFP-EGFP-LC3 plasmid into the LX-2 cells. CsESPs had more powerful to induce the accumulation of autophagosomes and autolysosomes to enhance autophagic flux compared with CsTP. Western-blotting analysis confirmed that the ratio of LC3-II/I in LX-2 cells was up-regulated after CsESPs treatment for 6 h, which further proved that CsESPs could induce autophagy in LX-2 cells. Meanwhile, q-PCR results showed that the mRNA levels of collagen I, collagen III and α-SMA decreased in LX-2 cells after treatment with autophagy inhibitor chloroquine, whereas they increased when combination with CsESPs. Conclusions: These results suggested that CsESPs-induced autophagy might be involved in the activation of HSCs, and consequently participate in the pathogenesis of hepatic fibrosis caused by C. sinensis infection. [ABSTRACT FROM AUTHOR]

Computing the grain boundary (GB) counterparts to bulk phase diagrams represents an emerging research direction. Using a classical embrittlement model system Ga-doped Al alloy, this study demonstrates the feasibility of computing temperature- and composition-dependent GB diagrams to represent not only equilibrium thermodynamic and structural characters, but also mechanical properties. Specifically, hybrid Monte Carlo and molecular dynamics (MC/MD) simulations are used to obtain the equilibrium GB structure as a function of temperature and composition. Simulated GB structures are validated by aberration-corrected scanning transmission electron microscopy. Subsequently, MD tensile tests are performed on the simulated equilibrium GB structures. GB diagrams are computed for not only GB adsorption and structural disorder, but also interfacial structural and chemical widths, MD ultimate tensile strength, and MD tensile toughness. This study suggests a research direction to investigate GB composition–structure–property relationships via computing GB diagrams of thermodynamic, structural, and mechanical (or potentially other) properties. [ABSTRACT FROM AUTHOR]

Wound exudate holds great clinical and research potential in wound repair via paracrine signaling. In essence, exudate is modified serum that contains a high concentration of exosomes. The aim of this study was to investigate the role of serum-derived exosomes in scald wound healing of NIH mice skin and to explore the underlying mechanisms. Hence, we constructed a deep second-degree scald model in NIH mice, testing the benefits of exosomes in the scald wound healing. The scratch wound assay, apoptosis assay and MTT assay were conducted to assess the effects of serum-derived exosomes on migration, apoptosis and proliferation of HaCaT cells and fibroblasts. Our results showed that serum-derived exosomes injected subcutaneously entered cells and effectively accelerated wound healing processes in mice. Additionally, serum-derived exosomes optimized functions of cells related to skin injury repair by stimulating fibroblast proliferation, promoting HaCaT cell migration, and suppressing apoptosis of HaCaT cells induced by heat stress. Further study revealed that serum-derived exosomes enhanced phosphorylation of the serine-threonine kinase Akt in scalded skin tissue. These results suggest a potential clinical use of serum-derived exosomes for treating skin scald. [ABSTRACT FROM AUTHOR]

Titanium alloys are promising candidates for biomedical applications, and alloys based on the Ti-rich side of Ti-Nb-Sn system have presented material properties deserved for orthopedic implant applications. However, to our knowledge, the structural studies related to surface of these alloys are limited. Ti-18Nb-11Sn and Ti-35Nb-4Sn alloys were synthesized, and the influence of thermochemical treatment on the bioactivity was investigated. The alloys were synthesized by arc melting furnace and then were submitted to thermochemical treatment. X-ray diffraction and scanning electron micrograph analysis showed high crystallinity and maintenance of microstructure of the both alloys before and after thermochemical treatment. The results indicated that the Ti-18Nb-11Sn alloy was not demonstrated to be bioactive, while the Ti-35Nb-4Sn alloy slightly presented bioactivity, which increased after the thermochemical treatment. Meanwhile, the Ti-18Nb-11Sn alloy presented a low hardness value, making it not compatible with biomedical applications. However, the Ti-35Nb-4Sn alloy presented an acceptable hardness value for biomedical applications. We believe that the results reported herein suggest that the Ti-35Nb-4Sn alloy may be attractive for designing biomedical devices with improved performances toward the adhesion of apatite. [ABSTRACT FROM AUTHOR]

Cathepsin L-like protease is an important member of the papain-like cysteine protease and plays numerous indispensable roles in the biology of parasitic organisms. In a previous study, we identified a gene encoding a cathepsin L-like protease of Clonorchis sinensis (CsCPL) that was detected in the cercaria, metacercaria, and adult worm stages by immunolocalization, suggesting that this cysteine protease may be important and involved in the development of C. sinensis. In this study, the mature domain of CsCPL (CsCPL-m) was cloned and expressed in the form of inclusion bodies in Escherichia coli. After refolding, the recombinant CsCPL-m displayed optimal protease activity towards Z-Phe-Arg-AMC substrates but not towards Z-Arg-Arg-AMC, and the activity of the protease was inhibited completely by the cysteine protease-specific inhibitors E-64 and IAA, which further demonstrated that CsCPL belongs to the cathepsin L-like cysteine protease family. Recombinant CsCPL-m exhibited considerable activity at temperatures ranging from 28 to 42 °C, with the highest activity observed at 42 °C. Furthermore, recombinant CsCPL-m exhibited activity across a broad range of pH values (pH 4.0-8.0), with an optimal pH of 5.5. The Km and Vmax of the recombinant CsCPL-m towards Z-Phe-Arg-AMC were determined to be 5.71 × 10−6 M and 0.6 μM/min, respectively, at 37 °C and pH 5.5. The recombinant CsCPL-m could degrade BSA and gelatine, but could not degrade human hemoglobin and human immunoglobulin G. These results implied that CsCPL might participate in the catabolism of host proteins for nutrition during the parasitic life cycle of C. sinensis; thus, CsCPL could be used as a potential vaccine antigen and drug target against C. sinensis infection. [ABSTRACT FROM AUTHOR]

Gliomas are the most common primary brain tumors. This meta-analysis aimed to systematically evaluate the relationship between CD147 expression in tissues and the clinicopathological features of patients with glioma. We searched PubMed (1966-2016), EMBASE (1980-2016), Cochrane Library (1996-2016), Web of Science (1945-2016), China National Knowledge Infrastructure (1982-2016), and Wan Fang databases (1988-2016). Quality assessment of the literature was performed using the Newcastle-Ottawa Scale, with Revman 5.3 and Stata 14.0 for analysis. In total, 1806 glioma patients from 19 studies were included, and patients with CD147 overexpression had poorer overall survival [hazard ratio (HR) = 2.211, P < 0.0001], a higher risk of recurrence (HR = 2.20, P = 0.0025), and a lower 5-year survival rate [odds ratio (OR) 0.12; 95% CI 0.08-0.19; P < 0.00001]. We observed significant differences in CD147 expression when comparing glioma tissues versus non-cancerous brain tissues (OR 20.42; 95% CI 13.94-29.91; P < 0.00001), tumor grades III-IV versus grades I-II (OR 5.88, 95% CI 4.15-8.34; P < 0.00001), and large versus small tumors (OR 1.58, 95% CI 1.04-2.40; P = 0.03). We also observed a significant correlation with matrix metalloproteinase (MMP) 2 (OR 39.11, 95% CI 11.47-133.34; P < 0.00001) and MMP9 (OR 13.35, 95% CI 4.67-38.18; P < 0.00001). CD147 expression did not differ based on patient's age (young vs. old, P = 0.89) or gender (female vs. male, P = 0.57). CD147 expression may be a potential prognostic biomarker for poorer overall and relapse-free survival, and may affect the 5-year survival rate in glioma patients. CD147 expression is also closely correlated with poor clinical characteristics in glioma patients. [ABSTRACT FROM AUTHOR]

Polo-like kinase (Plk) plays a central role in centrosome cycle and is closely associated with the oncogenesis of lung cancer. The protein consists of a catalytic kinase domain (KD) and a regulatory polo-box domain (PBD); either direct inhibition of the KD's catalytic activity or indirect disruption of the PBD-substrate interaction can be used to potentially suppress the pathological activation of lung cancer Plk. Here, we reported a successful molecular design and engineering of phosphopeptide ligands to target Plk PBD domain by integrating in silico modeling and in vitro assay. In the procedure, a helical peptide segment hps was derived from dimerization interface of the complex crystal structure of domain dimer using bioinformatics approach, which was then used as sequence template to generate potent phosphopeptide binders of Plk PBD domain in terms of a systematic residue mutation profile. Fluorescence anisotropy assays were conducted to substantiate the findings and conclusions obtaining from the molecular engineering. Consequently, three helical phosphopeptides, including the native hps and its two mutants hps-m and hps-m , were successfully designed that can independently rebind to Plk PBD domain with a moderate or high affinity ( K = 127, 26, and 5 μM, respectively). These peptide ligands can be considered as potent self-competitors to disrupt PBD dimerization in lung cancer metastasis. Structural and energetic analysis revealed that hydrophobic forces and van der Waals contacts confer strong stability for domain-peptide complex system, while hydrogen bonds and electrostatic interactions contribute specificity and selectivity to the complex recognition. [ABSTRACT FROM AUTHOR]

Small interfering RNAs (siRNAs) may induce to targeted gene knockdown, and the gene silencing effectiveness relies on the efficacy of the siRNA. Therefore, the task of this paper is to construct an effective siRNA prediction method. In our work, we try to describe siRNA from both quantitative and qualitative aspects. For quantitative analyses, we form four groups of effective features, including nucleotide frequencies, thermodynamic stability profile, thermodynamic of siRNA-mRNA interaction, and mRNA related features, as a new mixed representation, in which thermodynamic of siRNA-mRNA interaction is introduced to siRNA efficacy prediction for the first time to our best knowledge. And then an F-score based feature selection is employed to investigate the contribution of each feature and remove the weak relevant features. Meanwhile, we encode the siRNA sequence and existed empirical design rules as a qualitative siRNA representation. These two kinds of siRNA representations are combined to predict siRNA efficacy by supported Vector Regression (SVR) at score level. The experimental results indicate that our method may select the features with powerful discriminative ability and make the two kinds of siRNA representations work at full capacity. The prediction results also demonstrate that our method can outperform other popular siRNA efficacy prediction algorithms. [ABSTRACT FROM AUTHOR]