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Beta gallium oxide (β‐Ga2O3) has emerged as a highly promising semiconductor material with an ultrawide bandgap ranging from 4.5 to 4.9 eV for future applications in power electronics, optoelectronics, as well as gas and ultraviolet (UV) radiation sensors. Here, surface adsorption and air damping behavior of doubly clamped β‐Ga2O3 nanomechanical resonators are probed and systemically studied by measuring the resonance characteristics under different gas and pressure conditions. High responsivities of resonance to pressure are obtained by heating the devices up to 300 °C to induce an accelerated adsorption–desorption process. The initial surface conditions of the β‐Ga2O3 thin film play important roles in affecting the resonant behavior. UV ozone treatment proves effective in altering the initial surface conditions of β‐Ga2O3 nanosheets by eliminating physisorbed contaminants and filling oxygen vacancy defects residing on the surface, resulting in a consequential and discernible modification of the resonance behavior of β‐Ga2O3 nanomechanical resonators. The surface adsorption and desorption processes in β‐Ga2O3 demonstrate clear reversibility by exposing the UV treated β‐Ga2O3 to air. This study attains first‐hand information on how the surface conditions of β‐Ga2O3 affect its mechanical properties, and helps guide future development of transducers via β‐Ga2O3 nanoelectromechanical systems (NEMS) for pressure sensing applications, especially in harsh environments. [ABSTRACT FROM AUTHOR]

Pinus morrisonicola Hayata is a unique plant species found in Taiwan. Previous studies have identified its anti-hypertensive, anti-oxidative, and anti-inflammatory effects. In this study, a bioactivity-guided approach was employed to extract 20 compounds from the ethyl acetate fraction of the ethanol extract of Pinus morrisonicola Hayata's pine needles. The anti-aging effects of these compounds were investigated using HT-1080 cells. The structures of the purified compounds were confirmed through NMR and LC-MS analysis, revealing the presence of nine flavonoids, two lignans, one coumarin, one benzofuran, one phenylic acid, and six diterpenoids. Among them, PML18, PML19, and PML20 were identified as novel diterpene. Compounds 3, 4, and 5 exhibited remarkable inhibitory effects against MMP-2 and showed no significant cell toxicity at 25 μM. Although the purified compounds showed lower activity against Pro MMP-2 and Pro MMP-9 compared to the ethyl acetate fraction, we speculate that this is the result of synergistic effects. [ABSTRACT FROM AUTHOR]

Here, we characterized a new mycovirus from the fungus Nigrospora chinensis, which was named "Nigrospora chinensis victorivirus 1" (NcVV1). The NcVV1 genome is 5283 bp in length, containing two continuous open reading frames (ORFs), ORF1 and ORF2. ORF1 and ORF2 were predicted to encode a putative coat protein (CP) and an RNA-dependent RNA polymerase (RdRp), respectively. The stop codon of ORF1 overlaps with the start codon of ORF2 by the tetranucleotide sequence AUGA. Phylogenetic analysis based on amino acid sequences of RdRp and CP indicated that NcVV1 clustered with members of the genus Victorivirus in the family Totiviridae. To our knowledge, this was the first report of a mycovirus infecting N. chinensis. [ABSTRACT FROM AUTHOR]

The experimental demonstration of aluminum scandium nitride (AlScN)‐on‐cubic silicon carbide (SiC) heterostructure thin film micromachined resonant transducers operating in a high‐temperature environment up to 600 °C is reported. Macroscopic and microscopic vibrations are investigated through a combination of ultrasensitive laser interferometry techniques and Raman spectroscopy. An average linear temperature coefficient of resonance frequency (TCf) of <1 ppm °C−1 within the temperature range from room temperature to 200 °C, and an average linear TCf of −16 ppm °C−1 between 200 and 600 °C, from the fundamental‐mode resonance of AlScN/SiC circular diaphragm resonator with a thickness of 1.9 µm and diameter of 250 µm, is obtained. Higher‐order modes exhibit much larger TCf, which make them strong candidates as high‐temperature‐tolerant temperature sensors or ultraviolet detectors. Raman spectroscopy indicates that the turning points of the peak positions of the longitudinal optical phonon modes of both 3C‐SiC and AlScN occur in almost the same temperature region where the turnover point of TCf is observed, suggesting that the microscopic vibrations in the crystal lattice and the macroscopic oscillation of the diaphragm are naturally mediated by the residual strain inside the materials at varying temperature. [ABSTRACT FROM AUTHOR]

Pinus taiwanensis Hayata (Pinaceae) is an endemic plant in Taiwan. According to the Chinese Materia Medica Grand Dictionary, the Pinus species is mainly used to relieve pain, and eliminate pus and toxicity. In this study, nineteen compounds were isolated from the ethyl acetate layer of the ethanolic extract of P. taiwanensis Hayata twigs using bioassay-guided fractionation, and their anti-melanoma effects were investigated through a B16-F10 mouse melanoma cell model. The structures of the purified compounds were identified by 2D-NMR, MS, and IR, including 1 triterpenoid, 9 diterpenoids, 2 lignans, 4 phenolics, 1 phenylpropanoid, 1 flavonoid, and 1 steroid. Among them, compound 3 was found to be a new diterpene. Some of the compounds (2, 5, 6, 17, 18) showed moderate cytotoxicity effects. On the other hand, the anti-melanoma effect was no better than that from the original ethyl acetate layer. We presumed it resulted from the synergistic effect, although further experimentation needs to be performed. [ABSTRACT FROM AUTHOR]

Gallium nitride (GaN) has attracted great attention as a structural material for advanced microelectromechanical systems (MEMS), thanks to its excellent ensemble of electrical and mechanical properties. Here, we report on studying the effects of ion radiation-induced displacement damage on resonant MEMS made of GaN film grown on aluminum nitride (AlN) buffer layer. We design and fabricate GaN/AlN heterostructure doubly-clamped microstring resonators with length $L \,\, =100$ , 200, 300, 400, 500, 600, and 700 $\mu \text{m}$ , and irradiate the devices with 440-keV Ar $^{+}$ ions, to probe the effects of ion radiation-induced displacement damage on the resonance behavior. The ion energy and range have been selected so that the ions would stop within the GaN layer, thus allowing diagnostics to show the effects of damage in the structure. The multimode resonance frequencies of the devices decrease significantly ($\vert \Delta f\vert /f >50$ %) with the increase of fluence beyond 1014 cm−2. According to scanning electron microscopy (SEM) imaging, the irradiated GaN/AlN resonators are visibly deformed at high fluence, where the amount of curvature increases monotonically with the fluence. The deformation of the structures can be ascribed to the change in both Young’s modulus and built-in stress resulting from ion radiation-induced displacement damage. The results extend the understanding of radiation-induced damage mechanisms in resonant MEMS. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to determine whether periodontitis in early pregnancy and periodontal therapy during gestation affect the incidence of gestational diabetes mellitus (GDM) through a population‐based clinical study. Materials and methods: Subjects without periodontitis at 1–4 weeks of gestation who met our inclusion criteria were enrolled in the non‐periodontitis group. Periodontitis patients who agreed or refused to receive periodontal therapy during pregnancy were separately enrolled in the periodontitis treated or untreated group. At 12–16 weeks of gestation, gingival crevicular fluid (GCF) and venous blood were collected for analyses of bacterial species and serum inflammatory mediators, respectively. At 24–28 weeks of gestation, GDM patients were identified by oral glucose tolerance tests. The association tests were performed using Chi‐squared statistics and regression analyses. Results: The complete data of 3523 pregnant women were recorded during the study period. GDM incidence among the untreated periodontitis participants (84/749, 11.21%) was significantly higher than that among the non‐periodontitis participants (108/2255, 4.79%) (p <.05), and periodontal treatment during gestation reduced the incidence from 11.21% (untreated group) to 7.32% (38/519, treated group) (p <.05). Based on multiple logistic regression analyses, it was found that periodontitis in early pregnancy was associated with GDM, and three‐step regression analyses showed that Porphyromonas gingivalis (P. gingivalis) and the serum TNF‐α and IL‐8 levels played a role in the association between untreated periodontitis and GDM. Furthermore, Pearson's correlation test indicated that the existence of P. gingivalis in GCF was positively correlated with high serum levels of these two inflammatory mediators. Conclusions: This study establishes a connection between periodontitis in early pregnancy and GDM and demonstrates that the presence of P. gingivalis is associated with high levels of inflammatory mediators in serum, and thereby may contribute to the development of GDM. In‐depth mechanistic studies are needed to further support these findings. [ABSTRACT FROM AUTHOR]

We report on the first experimental characterization and analysis of the thermal response and temperature coefficient of resonance frequency (TC ƒ) of gallium nitride/aluminum nitride (GaN/AlN) heterostructure micro string resonators, in a wide temperature range from −10 °C up to 325 °C. Thanks to its excellent electrical and mechanical properties and chemical inertness, GaN has recently stimulated growing interests in GaN microelectromechanical systems (MEMS) for emerging high-power, high-temperature, and harsh-environment applications. GaN films on Si wafers often require AlN buffer layers, thus the residual tensile stress profile in the GaN epilayers and GaN/AlN hetero-layers can play a key role in affecting the MEMS specifications and performance. Here we design and fabricate GaN/AlN heterostructure micro string resonators with length L = 100, 200 and 300 μm to probe the stress and thermal effects on resonance behavior. All out-of-plane flexural modes show clear string behavior, and the multimode resonance frequencies downshift almost linearly with increasing temperature up to 325 °C. The linear temperature dependence and TC ƒ values of GaN/AlN heterostructure resonators can be directly employed for thermal sensing. Comparison among different devices indicates that higher tensile stress levels contribute to smaller TC ƒ values, suggesting strain engineering may be exploited for intentionally regulating the TC ƒ. [ABSTRACT FROM AUTHOR]

Rhizoctonia solani is a widespread and devastating plant pathogenic fungus that infects many important crops. This pathogen causes tobacco target spot, a disease that is widespread in many tobacco-growing countries and is destructive to tobacco. To identify antagonistic microorganisms with biocontrol potential against this disease, we isolated Streptomyces strains from forest inter-root soil and screened a promising biocontrol strain, ZZ-21. Based on in vitro antagonism assays, ZZ-21 showed a significant inhibitory effect on R. solani and various other phytopathogens. ZZ-21 was identified as Streptomyces olivoreticuli by its phenotypic, genetic, physiological and biochemical properties. Complete genome sequencing revealed that ZZ-21 harbored numerous antimicrobial biosynthesis gene clusters. ZZ-21 significantly reduced the lesion length in detached inoculated leaf assays and reduced the disease index under greenhouse and field conditions. Based on an in vitro antagonistic assay of ZZ-21 culture, the strain exhibited an antifungal activity against R. solani in a dose-dependent manner. The culture filtrate could impair membrane integrity, possibly through membrane lipid peroxidation. ZZ-21 could secrete multiple extracellular enzymes and siderophores. According to a series of antifungal assays, the extracellular metabolites of ZZ-21 contained antimicrobial bioactive compounds composed of proteins/peptides extracted using ammonium sulfate precipitation, which were stable under stress caused by high temperature and protease K. The EC 50 value for ammonium sulfate precipitation was determined to be 21.11 μg/mL in this study. Moreover, the proteins/peptides also exhibited biocontrol ability and were observed to alter the plasma membrane integrity of R. solani which were evaluated by biocontrol efficacy assays on detached tobacco leaves and PI staining. Overall, strain ZZ-21 shows the potential to be developed into a biopesticide against tobacco target spot disease. [Display omitted] • A Streptomyces strain ZZ-21 showed a significant inhibition effect on R. solani was isolated. • ZZ-21 was identified as Streptomyces olivoreticuli by phenotypic, genetic, physiological and biochemical properties. • The antimicrobial bioactive compounds was stable proteins/peptides. • ZZ-21 could impair membrane integrity of the pathogen fungus R. solani. [ABSTRACT FROM AUTHOR]

Background: The severe rigid deformity patients with pulmonary dysfunction could not tolerate complicated corrective surgery. Preoperative traction are used to reduce the curve magnitude and improve the pulmonary function before surgery, including halo-gravity traction (HGT) and halo-pelvic traction (HPT). The present study aimed to retrospectively compare the radiographic, pulmonary and clinical outcomes of preoperative HGT and HPT in severe rigid spinal deformity with respiratory dysfunction.Methods: 81 cases of severe rigid kyphoscoliosis treated with preoperative traction prior to corrective surgery for spinal deformity between 2016 and 2019 were retrospectively reviewed. Two patient groups were compared, HPT group (N = 30) and HGT group (N = 51). Patient demographics, coronal and sagittal Cobb angles and correction rates, pulmonary function, traction time, osteotomy grade, and postoperative neurological complications were recorded for all cases.Results: The coronal Cobb angle was corrected from 140.67 ± 2.63 to a mean of 120.17 ± 2.93° in the HGT group, and from 132.32 ± 4.96 to 87.59 ± 3.01° in the HPT group (mean corrections 15.33 ± 1.53 vs. 34.86 ± 3.11 %) (P = 0.001). The mean major sagittal curve decreased from 134.28 ± 3.77 to 113.03 ± 4.57° in the HGT group and from 129.60 ± 8.45 to 65.61 ± 7.86° in the HPT group (P < 0.001); the mean percentage corrections were 16.50 ± 2.13 and 44.09 ± 9.78 % (P < 0.001). A significant difference in the pulmonary function test results was apparent between the two groups; the mean improvements in the FVC% of the HGT and HPT groups were 6.76 ± 1.85 and 15.6 ± 3.47 % (P = 0.024). The HPT group tended to exhibit more FEV% improvement than the HGT group, but the difference was not significant (5.15 ± 2.27 vs. 11.76 ± 2.22 %, P = 0.91).Conclusions: Patients with severe rigid kyphoscoliosis who underwent preoperative HPT exhibited better radiographic correction of the deformity, and pulmonary function, and required fewer osteotomies compared to the HGT group. Thus, HPT may be useful for severe rigid spinal deformity patients with pulmonary dysfunction. [ABSTRACT FROM AUTHOR]

Spotted fever group rickettsiae (SFGR) and Coxiella burnetii are intracellular bacteria that cause potentially life‐threatening tick‐borne rickettsioses and Q fever respectively. Sao Tome and Principe (STP), small islands located in the Gulf of Guinea, recently experienced a dramatic reduction in the incidence of malaria owing to international collaborative efforts. However, unexplained febrile illnesses persist. A One Health approach was adopted to investigate exposure to SFGR and C. burnetii in humans and examine the diversity of these bacteria in ticks parasitizing domestic ruminants. A cross‐sectional human serological study was conducted in Agua Grande district in Sao Tome Island from January to March 2016, and ticks were collected from farmed domestic ruminants in 2012 and 2016. In total, 240 individuals varying in age were randomly screened for exposure to SFGR and C. burnetii by indirect immunofluorescence assay. Twenty of 240 individuals (8.3%) were seropositive for SFGR (4 for Rickettsia africae and 16 for R. conorii) and 16 (6.7%) were seropositive for C. burnetii. Amblyomma astrion were collected exclusively in 2012, as were A. variegatum in 2016 and Rickettsia spp. were detected in 22/42 (52.4%) and 49/60 (81.7%) respectively. Sequence analysis of multiple gene targets from Rickettsia spp. detected in ticks suggests the presence of a single divergent R. africae strain (Sao Tome). While no ticks were found positive for C. burnetii, Coxiella‐like endosymbionts were detected in nearly all ticks. This is the first study in STP to provide serological evidence in humans of SFGR and C. burnetii and additional molecular evidence in ticks for SFGR, which may be responsible for some of the unexplained febrile illnesses that persist despite the control of malaria. Future epidemiological studies are needed to confirm the occurrence and risk factors associated with SFG rickettsioses and Q fever in both humans and animals. [ABSTRACT FROM AUTHOR]

The resistive switching of polymer films embedded with nanoparticles (NPs) offers the promise for future flexible and transparent memory applications. However, the polymer/NP interfacial effect on switching behavior under various mechanical stimuli is a vital issue that has received scant attention. Here, polymer thin films embedded with TiO 2 NPs were fabricated by vacuum spray method to study how the polymer/NP interface affects the switching behavior, especially under severe bending conditions. Compared with that of the initial sample, the ON/OFF ratio decreases by two orders of magnitude with the conduction mechanism translating from trap-controlled space charge limited current conduction to Poole−Frankel emission after repetitive bending. Surface wrinkle and interfacial micro cracks were observed. Using the finite element analyses and quantum chemical calculation, we show that the TiO 2 NPs produce strain-sensitive regions within the film, and micro cracks initiate and propagate along the polymer/NP interface under severe bending. Such cracks can serve as vacuum gap to block the carriers transport and further result in the deterioration of switching performance. [ABSTRACT FROM AUTHOR]

Pre-stressed high-strength concrete (PHC) pipe piles have been widely used in the pile foundations of buildings and bridges which are usually designed elastic based on the capacity design principle. However, when the PHC pipe pile comes to the foundations of Integral Abutment Jointless Bridges (IAJBs), limited ductility might apply in order to accommodate the relatively large deformation demand under the effect of temperature fluctuations or earthquake. The conventional design methods for PHC pipe piles remain in doubt. This paper focuses on low cycle pseudo-static tests on 4 PHC pipe-pile models with various pre-stress levels to gain insight into their mechanical behaviors with consideration of soil-pile interaction. Medium sand was employed in the tests. The details of the experiments are introduced, including design of the models, instrumentation and loading scheme. The testing results indicate that the damages of the PHC pipe piles are mainly concentrated at 4D to 8D of embedded depths. Moreover, the pre-stress level and reinforcement ratio have a significant influence on the failure mode of PHC pipe piles, especially on the distribution of internal force and moment along piles. It is found that the interaction effect of pile-soil strengthens with the pre-stress level which is beneficial to the seismic performance. Furthermore, the backbone of the PHC pipe piles model has four stages: elastic, elastic-plastic, plastic hardening, and failure. It is concluded that PHC pipe piles perform favorably plastic and ductile behavior, and their failure modes are flexural (bending) not brittle (shear). Finally, the PHC pipe pile has an appreciable energy dissipation and deformation capacity, and hence can be used for pile foundations in IAJBs. [ABSTRACT FROM AUTHOR]

Objective To assess the clinical and radiographic outcomes of posterior vertebral column resection (PVCR) without anterior support in treatment of Yang type A severe rigid thoracic kyphoscoliosis. Methods The records of 27 Yang type A severe thoracic kyphoscoliosis patients treated with PVCR without anterior support from January 2010 to September 2013 were analyzed retrospectively. Intraoperative multimodal neurophysiological monitoring was conducted in all patients. The 6 modes were somatosensory evoked potential, motor evoked potential, descending neurogenic evoked potential, spinal cord evoked potential, and electromyography (both triggered and free run). Radiographic parameters and complications were used to evaluate the clinical outcomes. Results PVCR without anterior support was conducted successfully in all 27 patients. Intraoperative monitoring events occurred in 3 patients (3/27); of these, 1 patient (1/27) showed postoperative spinal cord injury, but completely recovered within 9 months after the operation (Frankel level E). The number and osteotomy space of vertebrae resection were mean 1.33 levels and 3.7 cm, respectively. All cases achieved good coronal and sagittal curve correction. No implant related complications occurred until the latest follow-up. The average follow-up was 40.1 months (range, 24–59 months). Conclusions In this study, we found that posterior vertebral column resection (PVCR) without any anterior support with a mean 3.7 cm shortening of the spinal column is safe, if close and unyielding contact of end plates can be obtained. A comprehensive understanding of the technique and intensive intraoperative neuromonitoring is mandatory to perform these challenging and complex spine deformity correction procedures safely. [ABSTRACT FROM AUTHOR]

Addressable molecular junctions based on a thiol-functionalized oligo (3-methylthiophene) derivative incorporated with pyridine unit were fabricated using polymer stamp-printing method. The junction charge transport was measured from 95 to 299 K under both dark and light conditions. Asymmetric current–voltage characteristics with temperature, light, and bias-direction dependence were observed. Simmons tunneling combined with hopping play dominant roles at low bias under both dark and light. The thermionic and Poole–Frankel emissions are also found to affect the charge transport in some cases. Based on the density functional theory in conjunction with the non-equilibrium Green's function method, we investigated the transport properties of a series of single-molecule junctions with different molecular structures, in which negative differential resistance was observed. Density functional theory calculation and transmission spectrum show that the tunneling barrier may depend on the relative energetic position of the frontier molecular orbitals with respect to the metal Fermi level under the effects of bias and temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method for energy storage ejection is proposed using superelastic SMA wire. • A novel concept of correlating energy and SMA resistance change rate is proposed. • Ejection energy density and energy conversion efficiency are investigated by test. • Theoretical prediction model for ejection energy density of SMA wire is developed. Superelastic shape memory alloy (SMA) wire is a memorable deformation material with large resilience and high energy density. In this paper, a revolutionary and yet explainable property of the SMA is investigated and confirmed: superelastic SMA energy storage and release can be quantitatively measured using electrical resistance. This finding boosted the SMA with significant advantages and potential in the field of mechanical energy storage and ejection release. A state-of-the-art energy storage ejection device is designed to test the relationship among SMA wires' stress, strain, and electrical resistance. The resistance change rate, ejection energy density and energy conversion efficiency are studied in the SMA wire energy tests. The experimental results confirm that the resistance change rate of the superelastic SMA wire has a stable linear relationship with the strain. The ejection energy density increases with the resistance change rate. A theoretical model of the relationship between the ejection energy density and resistance change rate is established based on the experimental results. In conclusion, the superelastic SMA wire can achieve sophisticated tasks that require 'programmable' and predictable energy storage or ejection. [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF) plays an important role in neuronal survival, neurite outgrowth and synaptic plasticity by activating the receptor tropomyosin receptor kinase B (TrkB, also known as NTRK2). TrkB has been shown to undergo recycling after BDNF stimulation. We have previously reported that full-length TrkB (TrkB-FL) are recycled through a Rab11-dependent pathway upon BDNF stimuli, which is important for the translocation of TrkB-FL into dendritic spines and for the maintenance of prolonged BDNF downstream signaling during long-term potentiation (LTP). However, the identity of the motor protein that mediates the local transfer of recycled TrkB-FL back to the plasma membrane remains unclear. Here, we report that the F-actin-based motor protein myosin Va (Myo5a) mediates the postendocytic recycling of TrkB-FL. Blocking the interaction between Rab11 and Myo5a by use of a TAT-tagged peptide consisting of amino acids 55-66 of the Myo5a ExonE domain weakened the association between TrkB-FL and Myo5a and thus impaired TrkB-FL recycling and BDNF-induced TrkB-FL translocation into dendritic spines. Finally, inhibiting Myo5a-mediated TrkB-FL recycling led to a significant reduction in prolonged BDNF downstream signaling. Taken together, these results show that Myo5a mediates BDNF-dependent TrkB-FL recycling and contributes to BDNF-induced TrkB spine translocation and prolonged downstream signaling. [ABSTRACT FROM AUTHOR]

Topological configurations play an important role in graphene nanoribbon based devices. In this work, the Büttiker's ac transport theory is used to study an asymmetric three terminal graphene nanoribbon structure. With the help of Green's function and related parameters, we show that the topological asymmetries can form capacitive and inductive junctions in this three terminal structure. The transport properties are sensitive to the geometric features of the branches of the junctions and the coupling positions. It is believed that this kind of structure can be useful for the future nanoelectronic devices. [ABSTRACT FROM AUTHOR]

Abstract: Bullous pemphigoid (BP) is a cutaneous autoimmune inflammatory disease associated with subepidermal blistering and autoantibodies against BP180, a transmembrane collagen and major component of the hemidesmosome. Numerous inflammatory cells infiltrate the upper dermis in BP. IgG autoantibodies in BP fix complement and target multiple BP180 epitopes that are highly clustered within a non-collagen linker domain, termed NC16A. Anti-BP180 antibodies induce BP in mice. In this study, we generated a humanized mouse strain, in which the murine BP180NC14A is replaced with the homologous human BP180NC16A epitope cluster region. We show that the humanized NC16A (NC16A+/+) mice injected with anti-BP180NC16A autoantibodies develop BP-like subepidermal blisters. The F(ab′)2 fragments of pathogenic IgG fail to activate the complement cascade and are no longer pathogenic. The NC16A+/+ mice pretreated with mast cell activation blocker or depleted of complement or neutrophils become resistant to BP. These findings suggest that the humoral response in BP critically depends on innate immune system players. [Copyright &y& Elsevier]

Abstract: The present study investigated the role of integrin-linked kinase (ILK) in TGFβ1-stimulated invasion/migration of human ovarian cancer cells. We investigated TGFβ1 regulation of ILK, and effects of ILK knockdown on TGFβ1-stimulated invasion/migration and the associated proteinase systems, urokinase plasminogen activator (uPA) and matrix metalloproteinases (MMPs) in SKOV3 cells. TGFβ1 stimulated ILK kinase activity, and had no effect on ILK protein/mRNA levels. Transient transfection of an ILK-specific siRNA (ILK-H) reduced ILK protein level, mRNA level and kinase activity. ILK knockdown by ILK-H suppressed the basal and TGFβ1-stimulated invasion and migration. Further, ILK-H reduced the basal and TGFβ1-stimulated secretion of uPA, and increased the secretion of its inhibitor (PAI-1). Conversely, ILK-H did not affect TGFβ1-stimulated secretion of MMP2 and its cell-associated activator MT1-MMP. Additionally, TGFβ1 activated Smad2 phosphorylation, and this was not affected by ILK knockdown. Earlier reports indicate that Smad2 activation increased the expression of MMP2 and MT1-MMP. Thus, TGFβ1 may act through ILK-independent and Smad2-dependent signaling in regulating MMP2 and MT1-MMP in SKOV3 cells. Collectively, this study suggests that ILK serves as a key mediator in TGFβ1 regulation of uPA/PAI-1 system critical for the invasiveness of human ovarian cancer cells. And ILK is a potential target for cancer therapy. [Copyright &y& Elsevier]

In this novel study, we isolated 28 compounds from the leaves of Aquilaria sinensis (Lour.) Gilg based on a bioassay-guided procedure and also discovered the possible matrix metalloprotease 2 (MMP-2) and 9 (MMP-9) modulatory effect of pheophorbide A (PA). To evaluate the regulatory activity on MMP-2 and MMP-9, the HT-1080 human fibrosarcoma cells were treated with various concentrations of extracted materials and isolated compounds. PA was extracted by methanol from the leaves of A. sinensis and separated from the fraction of the partitioned ethyl acetate layer. PA is believed to be an active component for MMP expression since it exhibited significant stimulation on MMP-2 and proMMP-9 activity. When treating with 50 μM of PA, the expression of MMP-2 and MMP-9 were increased 1.9-fold and 2.3-fold, respectively. PA also exhibited no cytotoxicity against HT-1080 cells when the cell viability was monitored. Furthermore, no significant MMP activity was observed when five PA analogues were evaluated. This study is the first to demonstrate that C-17 of PA is the deciding factor in determining the bioactivity of the compound. The MMP-2 and proMMP-9 modulatory activity of PA indicate its potential applications for reducing scar formation and comparative medical purposes. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) HPLC system focusing on the determination of phenylalanine (Phe) enantiomers in mammalian physiological fluids has been developed. ᴅ-Phe is indicated to have potential values as a disease biomarker and therapeutic molecule in several neuronal and metabolic disorders, thus the regulation of ᴅ-Phe in mammals is a matter of interest. However, the precise determination of amino acid enantiomers is difficult in complex biological samples, and the development of an analytical method with practically acceptable sensitivity, selectivity and throughput is expected. In the present study, a 2D-HPLC system equipped with a reversed-phase column in the 1st dimension and an enantioselective column in the 2nd dimension has been designed, following the fluorescence derivatization of the target amino acid enantiomers with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F). The analytical method was validated using both plasma and urine samples, and successfully applied to human, rat and mouse fluids. Trace levels of ᴅ-Phe were determined in the plasma, and the %ᴅ values were around 0.1% for all species. In the urine, relatively large amounts of ᴅ-Phe were observed, and the %ᴅ values for humans, rats and mice were 3.99, 1.76 and 5.25%, respectively. The relationships between the enzymatic activity of ᴅ-amino acid oxidase (DAO) and the amounts of intrinsic ᴅ-Phe have also been clarified, and high ᴅ-Phe amounts were observed (around 0.3% in the plasma and around 50% in the urine) in the DAO deficient rats and mice. • A 2D-HPLC system for Phe enantiomers in mammalian plasma and urine was developed. • The analytical method was successfully validated using both plasma and urine. • Trace levels of D-Phe (%D around 0.1%) were determined in the plasma for all species. • High D-Phe amounts were observed in the DAO deficient rats and mice. [ABSTRACT FROM AUTHOR]

Spin-dependent ac transport problem is studied with exchange effects. Spin-spin exchange interaction and charge-charge Coulomb interaction are included simultaneously to determine the landscape of internal potential and the spin-dependent ac conductance. Gauge invariance and charge conservation are still satisfied. But spin current is not conserved. It is found that the exchange effects affect spin conductance dramatically, and hardly influence charge conductance. This shows the role of spin-accumulation in spin-dependent transport. [ABSTRACT FROM AUTHOR]

Background The use of posterior vertebral column resection (PVCR) has extended the treatment of severe spinal deformity. However, the practice guidelines for anterior column support in patients treated by PVCR remain ill defined. The objective of the present study was to compare the clinical and radiographic outcomes of severe thoracic spinal deformity treated by PVCR with and without anterior column support (ACS). Methods We performed a prospective study of 57 patients with severe thoracic deformity (classified as Yang's A type) treated by PVCR with or without anterior column support from January 2010 to April 2015. The patient characteristics, radiographic parameters, intraoperative data, and complications were analyzed to clarify these 2 clinical series. Results The sex, age, diagnosis, curve magnitude, and curve type were similar between the PVCR with ACS group (n = 21) and non-ACS group (n = 36) preoperatively. Evaluation of the radiographic parameters, intraoperative data, and complications found no statistically significant intergroup differences, except for the osteotomy distance (non-ACS group, 4.0 cm; ACS group, 5.3 cm; P < 0.001) and shortening distance of the osteotomy gap (non-ACS group, 4.0 cm; ACS group, 3.5 cm; P = 0.005). Conclusions The results of the present study have shown that PVCR without ACS seems to be a safe and effective technique for Yang's A type severe thoracic spinal deformity correction compared with PVCR with ACS. PVCR without ACS requires a relatively smaller osteotomy range and could potentially decrease the risk of implant failure due to bone to bone fusion. Highlights • Non-ACS group with 4.0-cm osteotomy gap shortening is safe and effective for Yang's type A severe thoracic spinal deformity. • The osteotomy range can be effectively decreased using the non-ACS technique compared with the ACS technique. • The non-ACS technique can potentially decrease the risk of implant failure owing to bone to bone fusion. [ABSTRACT FROM AUTHOR]

In this paper, the large signal operation of the ring oscillator based injection locked frequency divider is analyzed considering the trade-offs among the operating frequency, locking range and power consumption. A large signal model is used to reveal several key findings such as voltage-limited locking ranges and asymmetry between the upper and lower locking bands. They are applied to the optimize the dividers maintaining a good balance among design considerations. Several prototypes, including the divide-by-2 with 3 and 5 stages of inverters, divide-by-3 and divide-by-5, are implemented in a standard 0.18 µm CMOS technology to verify the operation under a large injected signal. As an extension, dual-modulus prescalers are further designed by the integration of switches for different ways of signal mixing. Measurements results show the proposed divide-by-2/3 unit and a divide-by-8/9 with this unit are able to work up to 8 GHz and 4.0 GHz with maximum power consumption of 0.7 mW and 1.5 mW respectively. [ABSTRACT FROM AUTHOR]

In this paper, the design challenges of the injection-locked oscillator (ILO)-based phase shifter are reviewed and analyzed. The key design considerations such as the operating frequency, locking range, and linearity of the phase shifters are analysed in detail. It is possible to optimize the phase shifter in certain parameters such as ultra-low power while meeting the requirements of a certain system. As a design example, a K-band phase shifter is implemented using a commercial 0.13 μm CMOS technology, where a conventional LC tank based topology is implemented but optimised with a good balance among power consumption, working range, sensitivity, and silicon area, etc. Measurement results show that the proposed phase shift is able to work at 22-23.4 GHz with a range of 180 while consuming 3.14 mW from a 1.2 V supply voltage. [ABSTRACT FROM AUTHOR]

Canine mammary tumors (CMTs) are the most common type of tumors in female dogs. Heat shock proteins are highly expressed in many cancers and are involved in tumor progression and chemoresistance in CMTs; however, the biological role of canine heat shock protein 27 (cHSP27) in CMTs has not been thoroughly characterized. This study investigated the roles of cHSP27 in cell growth, migration, anchorage, and resistance to doxorubicin (DOX) using DTK-F cells, a CMT cell line that does not express cHSP27. DTK-F cells were transfected with cHSP27 and stable overexpression was established. A mouse monoclonal antibody against cHSP27 was also produced. The biological functions of cHSP27 in DTK-F cells were then evaluated using a variety of assays. Overexpression of cHSP27 was associated with increased cell proliferation, clone formation, migration, and decreased DOX sensitivity. In conclusion, these data provide evidence that cHSP27 overexpression can promote anchorage-independent growth, migration, and increased DOX resistance in CMT cells. [ABSTRACT FROM AUTHOR]

Local anesthetics have been reported to induce apoptosis in various cell lines. In this study, we showed that bupivacaine also induced apoptosis in DTK-SME cells, a vimentin+/AE1+/CK7+/HSP27+, tumorigenic, immortalized, canine mammary tumor cell line. Bupivacaine induced apoptosis in DTK-SME cells in a time- and concentration-dependent manner. Apoptosis-associated morphological changes, including cell shrinkage and rounding, chromatin condensation, and formation of apoptotic bodies, were observed in the bupivacaine-treated DTK-SME cells. Apoptosis was further confirmed with annexin V staining, TUNEL staining, and DNA laddering assays. At the molecular level, the activation of caspases-3, -8, and -9 corresponded well to the degree of DNA fragmentation triggered by bupivacaine. We also demonstrated that the pan-caspase inhibitor, z-VAD-fmk, only partially inhibited the apoptosis induced by bupivacaine. Moreover, treated cells increased expression of endonuclease G, a death effector that acts independently of caspases. Our data suggested that bupivacaine-induced apoptosis occurs through both caspasedependent and caspase-independent apoptotic pathways. [ABSTRACT FROM AUTHOR]

From the spin–spin interaction, spin-capacitive term is defined in a similar way to the usual charge capacitive term that is due to the charge–charge interaction. The charge and spin capacitive effects between the gate and central channel region are found to play an important role in gate-controlled spin-dependent transport systems. Both the capacitive terms affect system’s charge and spin ac transport properties. The behaviors of conductance, density of states, and internal potentials demonstrate the strong involvement of charge and spin in electrons in spin-dependent transport. The purpose of this paper is to draw attention to the Coulomb and exchange interactions in spintronics devices. [ABSTRACT FROM AUTHOR]

A new phase shifter based on injection‐locked ring oscillator is proposed. By using a multi‐stage phase generator with voltage‐controlled injection locking technique, the proposed phase shifter is able to generate a flexible combination of coarse and fine‐tuned phase delays over a wide range of operating frequencies while a small silicon area is maintained. Fabricated in a 0.18 µm RF CMOS process which only occupies 50 × 40 µm, a proposed three‐stage phase shifter achieves flexible phase delays and a measured operating frequency up to 2 GHz with a maximum power consumption of 2 mW from a 1.8 V supply. [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF) plays an important role in the activity-dependent regulation of synaptic structure and func-tion via tropomyosin related kinase B (TrkB) receptor activation. However, whether BDNF could regulate TrkB levels at synapse during long-term potentiation (LTP) is still unknown. We show in cultured rat hippocampal neurons that chemical LTP (cLTP) stimuli selec-tively promote endocytic recycling of BDNF-dependent full-length TrkB (TrkB-FL) receptors, but not isoform T1 (TrkB.Tl) receptors, via a Rabl 1-dependent pathway. Moreover, neuronal-activity-enhanced TrkB-FL recycling could facilitate receptor translocation to post-synaptic density and enhance BDNF-induced extracellular signal-regulated kinase and phosphatidylinositol 3-kinase activation and rat hippocampal neuron survival. Finally, we found that cLTP could stimulate the switch of Rabl 1 from an inactive to an active form and that GTP-bound Rabll could enhance the interaction between TrkB-FL and PSD-95. Therefore, the recycling endosome could serve as a reserve pool to supply TrkB-FL receptors for LTP maintenance. These findings provide a mechanistic link between Rabl 1-dependent endocytic recycling and TrkB modulation of synaptic plasticity. [ABSTRACT FROM AUTHOR]

Abstract: We examined the ac transport attribute of the multi-terminal structures in the absence and presence of magnetic field. We found that the ac response depends on the structural configurations and that the admittance varies with the features of the attached nanoribbons. In the vicinity of Dirac point the dc conductance manifests a dip or peak and the imaginary part (emittance) vanishes or not, depending on whether the attached ribbon is semiconductive or metallic. In the presence of magnetic field, the emittance becomes asymmetric reflecting the dynamic behaviors of electron and hole. [Copyright &y& Elsevier]

Abstract: Phonon transport in the uniform, dimer, Fibonacci and random atomic chains has been comparatively examined using the nonequilibrium atomistic Green''s function method, with particular focus on the interface effects. The tapered and the flat contact to the heat reservoir are compared. It is found that the thermal conductance of the atomic chain depends on both the order degree of the atomic chain structure and the interface configuration. The flat contact is found to favor phonon transmission between the reservoirs and the effect depends on the atomic chain structure as well. [Copyright &y& Elsevier]

Background: Difficult procedures of severe rigid spinal deformity increase the risk of intraoperative neurological injury. Here, we aimed to investigate the preoperative and intraoperative risk factors for postoperative neurological complications when treating severe rigid spinal deformity.Methods: One hundred seventy-seven consecutive patients who underwent severe rigid spinal deformity correction were assigned into 2 groups: the neurological complication (NC, 22 cases) group or non-NC group (155 cases). The baseline demographics, preoperative spinal cord functional classification, radiographic parameters (curve type, curve magnitude, and coronal/sagittal/total deformity angular ratio [C/S/T-DAR]), and surgical variables (correction rate, osteotomy type, location, shortening distance of the osteotomy gap, and anterior column support) were analyzed to determine the risk factors for postoperative neurological complications.Results: Fifty-eight patients (32.8%) had intraoperative evoked potentials (EP) events. Twenty-two cases (12.4%) developed postoperative neurological complications. Age and etiology were closely related to postoperative neurological complications. The spinal cord functional classification analysis showed a lower proportion of type A, and a higher proportion of type C in the NC group. The NC group had a larger preoperative scoliosis angle, kyphosis angle, S-DAR, T-DAR, and kyphosis correction rate than the non-NC group. The results showed that the NC group tended to undergo high-grade osteotomy. No significant differences were observed in shortening distance or anterior column support of the osteotomy area between the two groups.Conclusions: Postoperative neurological complications were closely related to preoperative age, etiology, severity of deformity, angulation rate, spinal cord function classification, intraoperative osteotomy site, osteotomy type, and kyphosis correction rate. Identification of these risk factors and relative development of surgical techniques will help to minimize neural injuries and manage postoperative neurological complications. [ABSTRACT FROM AUTHOR]

Titanium and its alloys are the main dental implant materials used at present. The biological properties of pure titanium can be further improved by surface treatment methods. Alkali treatment of pure titanium at room temperature can form nanonetwork structures (TNS) on the surface, which has better osteoinductive ability than pure titanium. However, TNS does not possess antimicrobial properties, and bacterial infection is one of the main reasons for the failure of dental implant therapy. Therefore, it was the focus of our research to endow TNS with certain antimicrobial properties on the premise of maintaining its osteoinductive ability. Because of its excellent broad-spectrum antimicrobial properties and because it promotes osteoblast-like cell growth, lactoferrin (LF) was considered a promising prospect as a surface biological treatment material. In this study, bovine LF of physiological concentration was successfully coated on the surface of TNS to form the TNS-LF composite material. Results from in vitro and in vivo experiments showed that TNS-LF had better osteoinductive ability than TNS. Bacterial attachment and biofilm formation were also significantly decreased on the surface of TNS-LF. Therefore, this study has provided an experimental basis for the development of osteoinduction-antimicrobial composite implant materials for dental applications. [ABSTRACT FROM AUTHOR]

Stromal-derived factor-1α (SDF-1α) is a chemokine signaling molecule that binds to the transmembrane receptor CXC chemokine receptor-4 (CXCR4) and carries out important functions in development tissue homeostasis. SDF-1α signaling via CXCR4 regulates the recruitment of stem and precursor cells to support tissue-specific repair or regeneration. In this study, we examined the contribution of SDF-1α signaling to the odontogenic differentiation of stem cells from the apical papilla (SCAP) induced by bone morphogenic protein 2 (BMP-2). CXCR4 expression was detected in cultured SCAP and SDF-1α promoted the migration of SCAP in Transwell assays. Blocking SDF-1α signaling by treatment with siRNA significantly affected BMP-2-induced mineralized nodule formation and alkaline phosphatase (ALP) activity. Moreover, blocking SDF-1α signaling inhibited the BMP-2-induced early expression of runt-related factor-2 (Runx-2) and strongly suppressed the induction of dentin matrix protein 1 (DMP-1) and dentin sialophosphoprotein (DSPP) expression by BMP-2. Furthermore, the interaction between SDF-1α and BMP-2 signaling was mediated via intracellular Smads and Erk activation. In conclusion, our results demonstrated that SDF-1α can significantly promote the migration of SCAP. Moreover, we revealed corequirement of the SDF-1α/CXCR4 signaling pathways in the BMP-2-induced odontogenic differentiation of SCAP, and these findings may be applied in new strategies for dental pulp regeneration. • A novel regulatory role of SDF-1α/CXCR4 in BMP-2 induced odontogenic differentiation. • Interaction between SDF-1α and BMP-2 signaling is mediated via Smad and Erk activation. • A promising therapeutic strategy for dentin-pulp engineering for future endodontic treatment. [ABSTRACT FROM AUTHOR]

Multimodal intraoperative neuromonitoring (IONM) has been proposed as an effective way to reduce permanent neurologic injury during spinal deformity surgery. However, few studies have reported evoked potential changes at different surgical stages of thoracic posterior vertebral column resection (PVCR). A total of 82 cases with severe thoracic deformity (Yang's A type) treated by PVCR in a single institution between January 2010 and March 2015 were reviewed. Multimodal IONM including somatosensory evoked potential, motor evoked potential, and descending neurogenic evoked potential was performed for real-time assessment of spinal cord function during surgery. The risk factors of neuromonitoring events at different surgical stages were documented and analyzed. Multimodal IONM was successfully performed in all 82 cases. Thirty-nine neuromonitoring events presented in 27 (32.9%) cases. Neurologic monitoring events were more likely to occur in patients with larger scoliosis and kyphosis, longer osteotomy closure distance, more Halo gravity traction, more screw insertion, and higher PVCR segments. The reasons for monitoring changes included 6 events during screw insertion, 20 during osteotomy, 9 during osteotomy gap closure, and 4 during deformity correction. New postoperative neurologic deficits were observed in 11 (13.4%) cases including 1 incomplete paraplegia, 8 transient cord deficits, and 2 nerve root injuries. Multimodal IONM can effectively identify neurologic deficits throughout surgery. Osteotomy and osteotomy gap closure are the surgical stages with the highest neurologic risks during PVCR procedures. It is imperative to improve dexterity since the majority of neuromonitoring events are caused by surgical techniques. [ABSTRACT FROM AUTHOR]

Background: Poor osseointegration of dental implants often occurs in osteoporotic patients and processed implant surfaces could help to improve the dilemma. Purpose: This study aimed to compare the effects of different titanium (Ti) surfaces on bone‐implant osseointegration in ovariectomized (OVX) sheep. Materials and Methods: Four groups were included: smooth titanium (ST) was merely polished Ti; micro titanium (MT) was treated with hydrofluoric acid (HF) for 30 minutes; strontium‐loaded nano titanium (NT‐Sr) was formed by magnetron sputtering; strontium‐loaded micro/nano titanium (MNT‐Sr) was fabricated by HF etching combined with magnetron sputtering. The biological responses were evaluated by human bone marrow‐derived mesenchymal stem cells (hBMMSCs) experiments in vitro. Osseointegration was evaluated in vivo after each surface implant was inserted into OVX sheep' mandibles. Results: The numbers of adhered and mineralized hBMMSCs increased significantly in the MNT‐Sr group. The bone‐implant contact and the maximal pull‐out force increased significantly with MNT‐Sr surface. The bone volume ratio and trabecular number of the MNT‐Sr group were significantly higher than others, whereas trabecular separation decreased. Conclusions: These results indicated that an MNT‐Sr surface promotes the differentiation of hBMMSCs in vitro and enhances bone‐implant osseointegration in vivo, which may be a promising option for clinical implants in osteoporotic patients. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study.Objectives: This study is to measure and analyze the changes of three-dimensional (3D) distances of spinal column and spinal canal at the three-column osteotomy sites and address their clinical and neurologic significance.Summary Of Background Data: Three-column osteotomies were developed to treat severe and stiff spine deformities with insufficient understanding on the safe limit of spine shortening and the relationship between the shortening distance of the spinal column and that of the spinal canal.Methods: Records of 52 continuous patients with severe and stiff scoliosis treated with three-column spine osteotomies at our institution from July 2013 to June 2015 were reviewed. The preoperative spinal cord function classification were type A in 31 cases, type B in 10 cases, and type C in 11 cases. The types of osteotomies carried out were extended pedicle subtraction osteotomy in nine patients and posterior vertebral column resection in 43 patients. Multimodality neuromonitoring strategies were adopted intraoperatively. 3D pre- and postoperative spine models were reconstructed from the computed tomography (CT) scans. The distances of convex and concave spinal column and the spinal canal shortening were measured and analyzed.Results: The spinal column shortening distance (SCSD) measured on the 3D models (27.8 mm) were statistically shorter than those measured intraoperatively (32.8 mm) (P < 0.05); however, they were strongly correlated statistically (r = 0.82). The central spinal canal shortening distance (CCSD) was significantly shorter than the convex SCSD (P < 0.05). The convex SCSD and CCSD were significantly shorter in cases with anterior column strut graft than in those with bone-on-bone fusion (P < 0.05).Conclusion: The shortening distance of the convex spinal column cannot represent that of the central spinal canal in patients with severe scoliosis. The spinal column shortening procedure in appropriately selected patient groups with bone-on-bone fusion is a viable option with the CCSD being significantly shorter than the convex SCSD.Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

This paper presents a bridged contactless measurement technique that can measure the resonant frequency and quality factor of a fully-integrated powered off voltage-controlled oscillator (VCO). Unlike the use of the conventional two-coil inductive link, the proposed technique uses an additional inductor to bridge the coupling between the LC tank and the external inductor serving measurement purposes. This makes it possible to examine the on-chip high frequency oscillator with an off-chip inductor at Printed Circuit Board (PCB) level. As an example, a K-band VCO as well as the proposed test structure have been designed and simulated using 0.13 μm CMOS technology. The quality factor and operating frequency of the oscillator are measured using the proposed contactless technique through extraction from the frequency response of a bridged inductive link. The efficiency of the method has been validated by full wave electromagnetic simulation. As a reference, the characterization of the oscillator is also obtained using the Cadence Spectre RF and Mentor Graphic's Calibre PEX commercial Electronic Design Automation (EDA) software. The results of these two solutions agree considerably well, which supports the feasibility and potentials of using this technique for contactless measurements. [ABSTRACT FROM AUTHOR]

Background: Adolescent idiopathic scoliosis (AIS) surgery usually require prolonged operative times with extensive soft tissue dissection and significant perioperative blood loss, and allogeneic blood products are frequently needed. Methods to reduce the requirement for transfusion would have a beneficial effect on these patients. Although many previous studies have revealed the efficacy of tranexamic acid (TXA) in spinal surgery, there is still a lack of agreement concerning the reduction of both blood loss and transfusion requirements of large dose tranexamic acid (TXA) in surgery for adolescent idiopathic scoliosis (AIS). The objective of this study was to elevate the efficacy and safety of a large dose tranexamic acid (TXA) in reducing transfusion requirements of allogeneic blood products in adolescent idiopathic scoliosis (AIS) surgery using a retrospective study designed with historical control group.Methods: One hundred thirty seven consecutive AIS patients who underwent surgery treatment with posterior spinal pedicle systems from August 2011 to March 2015 in our scoliosis center were retrospectively reviewed. Patients were divided into two groups, the TXA group and the historical recruited no TXA group (NTXA). Preoperative demographics, radiographic parameters, operative parameters, estimated blood loss (EBL), total irrigation fluid, number of patients requiring blood transfusion, mean drop of Hb (Pre-op Hb-Post-op Hb), haematocrit pre and post-surgery, mean volume of blood transfusion, hospitalization time, and adverse effect were recorded and compared.Results: All the patients were successfully treated with satisfied clinical and radiographic outcomes. There were 71 patients in the TXA group and 66 patients in the NTXA group. The preoperative demographics were homogeneity between two groups (P > 0.05). There were no significant difference in average operative time between two groups (209 min vs 215 min, p >0.05). Number of patients in the TXA group showed a significant decrease in transfusion requirements with an associated reduced intraoperative blood loss of nearly 45% compared with those in NTXA group (8 vs 37, 619 ml vs 1125 ml, P < 0.05). There were no significant difference in total irrigation fluid between two groups (540 vs 550, p >0.05). Additional, patients in NTXA group showed significant decrease of Hb compared with patients in TXA group (5.2 g/dL vs 3.3 g/dL, P < 0.05), No significant difference were found in hospitalization time between two groups (6.3 vs 7.2 days, P > 0.05). No minor adverse effects associated with use of TXA were noted.Conclusions: Use of large dose tranexamic acid routinely seems to be effective and safe in reducing allogenic blood transfusion and blood loss in adolescent idiopathic scoliosis surgery. [ABSTRACT FROM AUTHOR]

We investigate the charge relaxation resistances in a typical graphene nanoribbon FET (GNRFET). We show that the behavior of the charge relaxation resistances heavily depends on the exerted gate voltage and the structural details of the GNRFET. When there is 0 channel (blocked), 1 channel, and $N$ channels in the GNR as tuned by the gate voltage, the equilibrium charge relaxation resistance is roughly 1, 1/2$ , and 1/2N$ of Sharvin–Imry contact resistance ( ), respectively, whereas the nonequilibrium charge relaxation resistance is much smaller. Our results indicate that the charge relaxation resistances characterizing the information of dissipation, $RC$ time and noise can be controlled by the gate voltage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A phase transition detection method is proposed for self-sensing and robustness. • Excitation signal is optimized for the thermal cycle pretreatment of SMA wire. • Thermal equilibrium points and end points of phase transition are distinguished. • A detection algorithm is developed based upon filtering and outlier processing. • A resistance-displacement regression model is built for displacement estimation. Shape memory alloy (SMA) wires are widely used as actuators because of their simplicity, high energy ratio, and Joule heat activation. The resistance behavior caused by the phase transition can predict the stress or strain of the SMA wire, which is called self-sensing. At present, there are researches on detecting the start and end points of phase transition based on resistance. However, the anti-interference ability of these researches is poor, and it is difficult to identify the thermal equilibrium points. Therefore, this paper proposes a novel resistance-based phase transition detection method with good robustness and displacement estimation. Firstly, the excitation signal is optimized for the thermal cycle pretreatment of the SMA wire. Secondly, the interferences of the resistance signal are determined, which are noise, small current signals, and step signals. Finally, using filtering and outlier processing, a phase transition region detection algorithm based on the difference of resistance extreme values is proposed. Moreover, a resistance-displacement model is established through linear regression. The experimental results show that the proposed method effectively resists the interference of signals and has good robustness. The mean relative error between the estimated and measured displacements is 4.43%. The resistance-displacement model effectively estimates the displacement of the SMA wire actuator and distinguishes the thermal equilibrium points and the end points of the phase transition. The proposed method can be used potentially for real-time phase transition detection, overheating protection, power consumption reduction, and self-sensing drive of sensorless actuators. [ABSTRACT FROM AUTHOR]

One of the strategies to improve the outcome of anti-erbB2-mediated immunotherapy is to combine anti-erbB2 antibodies with T-cell-based adoptive immunotherapy, which can be achieved by expressing anti-erbB2 mAb on the surface of T cells. A single-chain variable fragment (scFv) from an anti-erbB2 mAb has been expressed on T cell surface to bind to erbB2-positive cells, and CD3ζ has been expressed as a fusion partner at C terminus of this scFv to transduce signals. T cells grafted with this chimeric scFv/CD3ζ were able to specifically attack target tumor cells with no MHC/Ag restriction. To test the effects of CD28 signal on cellular activation and antitumor effectiveness of chimeric scFv/CD3ζ-modified T cells, we constructed a recombinant anti-erbB2 scFv/Fc/CD28/CD3ζ gene in a retroviral vector. T cells expressing anti-erbB2 scFv/Fc/CD28/CD3ζ specifically lyzed erbB2-positive target tumor cells and secreted not only interferon-γ (IFN-γ) but also IL-2 after binding to their target cells. Our data indicate that CD3 and CD28 signaling can be delivered in one molecule, which is sufficient for complete T cell activation without exogenous B7/CD28 co-stimulation. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that the circadian clock modulates Ca2+-based signalling pathways, using low-temperature (LT)-induced Ca2+ signals. We investigated the relationship between diurnal and circadian modulation of LT-induced increases in cytosolic-free calcium ([Ca2+]cyt), and regulation of [Ca2+]cyt-dependent outputs of the LT-signalling network ( RD29A transcript abundance and stomatal closure). We measured [Ca2+]cyt non-invasively using aequorin, and targeted aequorin to the guard cell using a guard cell-specific GAL4-green fluorescent protein enhancer trap line. LT caused transient increases in whole plant and guard cell [Ca2+]cyt. In guard cells, the LT-induced [Ca2+]cyt elevation preceded stomatal closure. In whole plants, the magnitude of LT-induced [Ca2+]cyt transients, measured from the entire plant or specifically the guard cell, varied with the time of day: LT-induced [Ca2+]cyt transients were significantly higher during the mid-photoperiod than at the beginning or end. Diurnal variation in LT-induced guard cell [Ca2+]cyt increases was not correlated to diurnal variation in LT-induced stomatal closure. There was circadian modulation of LT-induced whole plant [Ca2+]cyt increases, which were correlated to the circadian pattern of RD29A induction. In order to understand the significance of LT-induced [Ca2+]cyt increases, we used a computer simulation to demonstrate that, in guard cells, LT-induced [Ca2+]cyt increases measured from a population of cells are likely to represent the summation of cold-induced single-cell [Ca2+]cyt oscillations. [ABSTRACT FROM AUTHOR]

Fibroblast activation protein alpha (FAP) is a cell-surface expressed type II glycoprotein that has a unique proteolytic activity. FAP has active soluble forms that retain the extracellular portion but lack the transmembrane domain and cytoplasmic tail. FAP expression is normally very low in adult tissue but is highly expressed by activated fibroblasts in sites of tissue remodelling. Thus, FAP is a potential biomarker and pharmacological target in liver fibrosis, atherosclerosis, cardiac fibrosis, arthritis and cancer. Understanding the biological significance of FAP by investigating protein structure, interactions and activities requires reliable methods for the production and purification of abundant pure and stable protein. We describe an improved production and purification protocol for His 6 -tagged recombinant soluble human FAP. A modified baculovirus expression construct was generated using the pFastBac1 vector and the gp67 secretion signal to produce abundant active soluble recombinant human FAP (residues 27–760) in insect cells. The FAP purification protocol employed ammonium sulphate precipitation, ion exchange chromatography, immobilised metal affinity chromatography and ultrafiltration. High purity was achieved, as judged by gel electrophoresis and specific activity. The purified 82 kDa FAP protein was specifically inhibited by a FAP selective inhibitor, ARI-3099, and was inhibited by zinc with an IC 50 of 25 μM. Our approach could be adopted for producing the soluble portions of other type II transmembrane glycoproteins to study their structure and function. • A highly productive baculovirus expression construct was established for soluble human fibroblast activation protein alpha. • A specific purification protocol was established. • The soluble recombinant protein showed high purity and high specific enzyme activity. • The purified protease was inhibited by zinc at physiological concentrations. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) exhibit oncogenic or tumor suppressive functions that contribute to the initiation and development of various types of human cancer. miR-149-3p has been reported to serve multiple roles in the regulation of proliferation, apoptosis and metastasis. However, the effects and detailed mechanism of miR-149-3p in oral squamous cell carcinoma (OSCC) remain unclear. In the present study, miR-149-3p mimic, mimic control, miR-149-3p inhibitor and inhibitor control were transiently transfected into Cal27 and SCC-9 cells. The viability, proliferation and apoptosis of OSCC cells were determined using Cell Counting Kit-8, colony formation and Annexin V assays, respectively. The mRNA expression levels of miR-149-3p and AKT2 were determined by reverse transcription-quantitative PCR. The protein expression levels of AKT2, cleaved caspase-3 and cleaved PARP were examined by western blot analysis. The binding of miR-149-3p to the AKT2 3′-untranslated region was evaluated by a dual luciferase reporter assay. In the present study, overexpression of miR-149-3p reduced the viability and proliferation of OSCC cells. By contrast, increased cell viability and proliferation was observed in miR-149-3p-deficient OSCC cells. Dual luciferase reporter assay indicated that miR-149-3p significantly decreased the luciferase activity of the wild-type AKT2 3′-untranslated region. Moreover, overexpression of miR-149-3p downregulated the mRNA and protein expression levels of AKT2, suggesting that miR-149-3p was a negative modulator of AKT2. Restoration of AKT2 efficiently reversed the miR-149-3p-mediated reduction in the proliferative capacity of OSCC cells. In addition, miR-149-3p enhanced the sensitivity of OSCC cells to the chemotherapeutic drug 5-fluorouracil. Taken together, the current findings revealed an inhibitory effect of miR-149-3p on the proliferation of OSCC cells through the post-transcriptional suppression of AKT2, and indicated a potential chemosensitizing function of miR-149-3p for the treatment of patients with OSCC. [ABSTRACT FROM AUTHOR]

Proteases catalyse irreversible posttranslational modifications that often alter a biological function of the substrate. The protease dipeptidyl peptidase 4 (DPP4) is a pharmacological target in type 2 diabetes therapy primarily because it inactivates glucagon-like protein-1. DPP4 also has roles in steatosis, insulin resistance, cancers and inflammatory and fibrotic diseases. In addition, DPP4 binds to the spike protein of the MERS virus, causing it to be the human cell surface receptor for that virus. DPP4 has been identified as a potential binding target of SARS-CoV-2 spike protein, so this question requires experimental investigation. Understanding protein structure and function requires reliable protocols for production and purification. We developed such strategies for baculovirus generated soluble recombinant human DPP4 (residues 29–766) produced in insect cells. Purification used differential ammonium sulphate precipitation, hydrophobic interaction chromatography, dye affinity chromatography in series with immobilised metal affinity chromatography, and ion-exchange chromatography. The binding affinities of DPP4 to the SARS-CoV-2 full-length spike protein and its receptor-binding domain (RBD) were measured using surface plasmon resonance and ELISA. This optimised DPP4 purification procedure yielded 1 to 1.8 mg of pure fully active soluble DPP4 protein per litre of insect cell culture with specific activity >30 U/mg, indicative of high purity. No specific binding between DPP4 and CoV-2 spike protein was detected by surface plasmon resonance or ELISA. In summary, a procedure for high purity high yield soluble human DPP4 was achieved and used to show that, unlike MERS, SARS-CoV-2 does not bind human DPP4. [ABSTRACT FROM AUTHOR]

Myocardial ischaemia-reperfusion (I/R) injury is a complex pathophysiological process. Current research has suggested that energy metabolism disorders, of which the abnormal consumption of fatty acids is closely related, compose the main pathological basis for myocardial I/R injury. Lipid droplets (LD) are critical regulators of lipid metabolism by LD-associated proteins. Among the lipid droplet proteins, the perilipin family members regulate lipolysis and lipogenesis through different mechanisms. Plin5, an important perilipin protein, promotes LD generation and lowers fatty acid oxidation, thus protecting the myocardium from lipotoxicity. This study investigated the protective effects of Plin5 in I/R myocardium. Our results indicated that Plin5 deficiency exacerbated the myocardial infarct area, aggravated left ventricular systolic dysfunction, reduced lipid storage, and elevated free fatty acids. Plin5-deficient myocardium exhibited severely damaged mitochondria, elevated reactive oxygen species (ROS) and malondialdehyde (MDA) levels, and decreased superoxide dismutase (SOD) activity. Furthermore, the decreased phosphorylation of PI3K/Akt in Plin5-null cardiomyocytes might contribute to I/R injury aggravation. In conclusion, Plin5, a new regulator of myocardial lipid metabolism, decreases free fatty acid peroxidation by inhibiting the lipolysis of intracellular lipid droplets, thus providing cardioprotection against I/R injury and shedding new light on therapeutic solutions for I/R diseases. [ABSTRACT FROM AUTHOR]