Background:
MicroRNAs (miRNAs) are known to regulate the inflammatory response in various cell types. However, the ability of miRNAs to modulate dendritic cells (DCs) function for allergen ...immunotherapy is unclear.
Objective:
To assess the role of miR‐23b in the regulation of ovalbumin (OVA)‐induced DC differentiation and function and to investigate the related molecular mechanisms.
Methods:
Bone marrow‐derived dendritic cells (BMDCs) were generated from murine bone marrow progenitor cells and subsequently stimulated with OVA to examine the profile of miRNA expression. After transfection with miR‐23b reagents, DCs were evaluated for endocytic ability, surface marker expression, cytokine secretion and CD4+ T‐cell differentiation. The possible roles of the Notch and NF‐κB signalling pathways were also evaluated. Human monocyte‐derived dendritic cells (MDDCs) were similarly evaluated as well.
Results:
Significant upregulation of miR‐23b was observed in BMDCs pulsed with OVA. Following miR‐23b transfection, BMDCs showed decreased OVA uptake, increased IL‐10 production, decreased IL‐12 production and an enhanced capacity to promote FoxP3+ CD4+ T regulatory cells (Tregs) differentiation. In addition, inactivation of the Notch1 and NF‐κB signalling pathways were observed. Conversely, inhibition of miR‐23b in BMDCs resulted in the opposite effects. In human MDDCs, miRNA23b transfection similarly increased IL‐10 and decreased IL‐12 production, and that treated human MDDCs induced increased FoxP3+ CD4+ T cells.
Conclusion:
Our findings provide evidence that miR‐23b is capable of inducing tolerogenic DC activity and Treg responses in vitro through the inhibition of the Notch1 and NF‐κB signalling pathways; thus, miR‐23b might represent a therapeutic target for the management of allergic diseases.
•HPLC separation of PEGs and amino-terminated PEGs due to ion-exchange mechanism.•Acetonitrile in water, common silica-based C18 or phenyl RP columns and ELSD used.•No obvious effect of molar mass by ...isocratic LCCC with optimal volatile buffer.
The separation and characterization of polyethylene glycols (PEGs) and amino-substituted derivatives on common silica-based reversed-phase packing columns using isocratic elution is described. This separation is achieved by liquid chromatography under the near critical conditions (LCCC), based on the number of amino functional end groups without obvious effect of molar mass for PEGs. The mobile phase is acetonitrile in water with an optimal ammonium acetate buffer. The separation mechanism of PEG and amino-substituted PEG under the near LCCC on silica-based packing columns is confirmed to be ion-exchange interaction. Under the LCCC of PEG backbone, with fine tune of buffer concentration, the retention factor ratios for benzylamine and phenol in buffered mobile phases, α(benzylamine/phenol)-values, were used to assess the ion-exchange capacity on silica-based reversed-phase packing columns. To the best of our knowledge, this is the first report on separation of amino-functional PEGs independent of the molar mass by isocratic elution using common C18 or phenyl reversed-phase packing columns.
ABSTRACT
We constrain the equation of state of quark stars within the Bayesian statistical approach using the mass and radius measurements of PSR J0030+0451 from NICER. Three types of bag models, ...with and without non-zero finite quark mass and/or superfluidity, are employed for quark stars made up with self-bound strange quark matter. We find the $90{{\ \rm per\ cent}}$ posterior credible boundary around the most probable values of the quark star maximum mass is $M_{\rm TOV}=2.38_{-0.23}^{+0.26}\, M_{\odot }$, within the model flexibility of the finite quark mass, the quark pairing gap, and the perturbative contribution from the one-gluon exchange. The radius of a canonical $1.4 \, M_{\odot }$ quark star is $R_{\rm 1.4}\sim 12.3\, {\rm km}$, smaller than the results based on neutron star models.
Deposition current during fabrication plays an important role in the microstructure and properties of titanium alloy components prepared by multi-wire arc additive manufacturing (MWAAM) technology. ...In this study, Ti basic heterogeneous alloy with Ti-6.5Al-3.5Mo-1.5Zr-0.3Si (TC11) as the main component was deposited using the MWAAM method with the deposition current ranging from 360 A to 400 A. The effects of deposition current on the microstructural evolution, mechanical and corrosion properties of the MWAAM titanium alloys were investigated, and the process-microstructure-property relationship was analyzed. The results show that the microstructure of as-received Ti basic heterogeneous alloy was mainly composed of lamellar primary α phase (αP) and transformed β phase (βT), and increasing the deposition current during the MWAAM process would result in the increased width of α phase and the decreased aspect ratio of α phase. The mechanical properties of MWAAM-deposited specimens decrease with increasing current, which means that phase composition played a dominant role in determining hardness. When increasing the deposition current during the MWAAM process the ultimate tensile strength (UTS) decreased from 843.75 to 804.38 MPa. The MWAAM-deposited Ti basic heterogeneous alloy featured excellent corrosion properties, the corrosion potential of the best specimen was − 311 mV SCE and the corrosion current density was 1.23 × 10−8 Acm−2. This study provides a better understanding of the effect of deposition current on the targeted deposition property in the MWAAM process, which will contribute to future process control, improvement and optimization.
An extruded Mg-5Zn-2.5Y-1Ce-0.5Mn alloy with uniform fine α-Mg grains, dispersed W-phase and T-phase and weak basal texture was prepared by the semi-continuous casting and one-pass extrusion methods. ...The deformation behaviors of the extruded alloy were tested at a temperature range from room temperature (RT) to 350 °C and a strain rate range from 1×10−2s−1 to 4×10−4s−1. The results and relevant mechanisms were analyzed by using the measured data of the strain rate sensitivity (m) and the activation energy (Q) and the observations of the morphologies of deformation and fracture surfaces. It was demonstrated that the tensile strengths decrease, while the elongation to failure tends to increase with increasing temperature or decreasing strain rate. The variation in mechanical properties with increasing temperature mainly arises from a change in opening deformation mechanisms from the dislocation slip at RT to the dislocation climb at 250 °C to the grain boundary (GB) sliding at 350 °C. At RT, the slightly decreased tensile strengths and slightly increased elongation to failure with decreasing strain rate are mainly attributed to the weak sensitivity of the dislocation slip to strain rate. At 250 °C, the lower tensile strengths and the larger elongation to failure at 4×10−4s−1 than that at 1×10−2s−1 are mainly attributed to the occurrence of the dynamic recrystallization (DRX) at lower strain rate, while such DRX does not occur at higher strain rate. At 350 °C, the lower tensile strengths and the much larger elongation to failure at 4×10−4s−1 than that at 1×10−2s−1 are attributed to the GB sliding accommodated by the lattice diffusion at lower strain rate, while the GB sliding at higher strain rate is accommodated by the GB diffusion.
It is well known that humus markedly increases soil aggregate stability, but at the same time strongly decreases the flocculation of clay particles in suspension. These seemingly inconsistent ...observations suggest the need for a deeper understanding of the physical mechanisms that govern clay–humus interactions. In this research, soil samples from an Entisol were used to explore the role of cationic polarization in humus‐increased soil aggregate stability and sodium (Na+) and potassium (K+) ions were used to characterize weak and strong polarization, respectively. The results showed that strong cationic polarization has a critical role in increased soil aggregate stability in the presence of humus. We concluded that, without cationic polarization, the effects of humus alone on soil aggregate stability were weak in the presence of monovalent metal cations. When we compared the individual contributions of humus and strong cationic polarization, the latter proved much more important than humus in increasing soil aggregate stability. The strongest increase in soil aggregate stability occurred when strong cationic polarization was coupled with humus. The combined analysis of activation energy of soil flocculation in suspension and soil aggregate stability in the presence of humus indicated that humus increased the long‐range electrostatic repulsive force of soil particles, and increased the short‐range attractive force of soil particles. Consequently, humus decreased the flocculation of soil particles in suspension but increased soil aggregate stability; all effects were adjusted by the strength of cationic polarization.
Highlights
Elucidation of physical mechanisms of cation–surface interactions that determine clay–humus interactions.
Cations at the particle surface of the clay–humus complex are strongly polarized.
Cationic polarization has a critical role in humus‐increased soil aggregate stability.
Without cationic polarization, the effect of humus alone on soil aggregate stability was weak.
Objective
Femoral hernias constantly present as incarceration or strangulation and require emergency surgery. Incarcerated and strangulated femoral hernia repair remains challenging and ...controversial. The aim of our study was to analyze the efficacy of preperitoneal tension-free hernioplasty via lower abdominal midline incision for incarcerated and strangulated femoral hernia.
Methods
Data of 47 patients who underwent emergency surgery for incarcerated or strangulated femoral hernias from January 2009 to December 2017 were retrospectively analyzed. According to the surgical incisions, they were divided into two groups: the observation group (21 cases) had a lower abdominal midline incision, and the control group (26 cases) had a traditional inguinal incision. General data of patients, intraoperative findings, operative time and postoperative complications were compared.
Results
Patient characteristics showed that the two groups were comparable.15 cases (31.9%) underwent intestinal resection, and 32 cases (68.1%) underwent first-stage tension-free repair in total. The rate of first-stage tension-free hernioplasty was significantly higher in the observation group (18/21, 85.7% vs 14/26 53.8%,
P
= 0.020). No additional incision was required in the observation group, while six cases of the control group (23.1%) had an additional incision for intestinal resection and anastomosis (
P
= 0.026). Mean operative time (53.6 ± 24.7 min vs 77.9 ± 36.5 min,
P
= 0.012) and the length of hospital stay (6.3 ± 4.2 days vs 10.3 ± 6.9 days,
P
= 0.020) were significantly shorter in the observation group. The time of return to normal physical activity resulted significantly reduced compared to the control group (9.2 ± 4.1 days vs 13.3 ± 6.6 days,
P
= 0.017). The total incidence of postoperative complication (including chronic pain, foreign body sensation, hernia recurrence, wound infection and seroma/hematomas) in the observation group was lower (14.3% vs 42.3%
P
= 0.037). There were two recurrences in the control group. No mesh-related infection and no mortalities in two groups.
Conclusions
Midline preperitoneal approach for incarcerated and strangulated femoral hernia is a convenient and effective technique. It can improve the rate of first-stage tension-free repair of incarcerated femoral hernia and allow intestinal resection through the same incision, and with lower rate of postoperative complications.
Inspired by biological gradient structure, Ti basic gradient heterogeneous alloy component from TC11 alloy to TC4 alloy was fabricated by multi-wire arc additive manufacturing (MWAAM). The chemical ...mixing, phase and microstructure evolution, microhardness distribution and tensile property of Ti basic gradient heterogeneous alloy were investigated through EDS, XRD, SEM, hardness tester and tensile tester. The results indicated that the alloy elements formed a long-distance gradient concentration distribution during the transition between two different titanium alloys due to dilution, remelting, and convective mixing in the molten pool. The intensity of diffraction peaks of Ti basic gradient heterogeneous alloy in the gradient region had no obvious change. The microstructure of MWAAM Ti basic gradient heterogeneous alloy was mainly consisted of lamellar αP, acicular αS, equiaxed αS and β matrix. Different morphology of the αS phase was mainly attributed to the wetting state of the second solid phase and grain boundary. In addition, the microstructure of α phase in Ti basic gradient heterogeneous alloy was significantly changed by the gradient distribution of alloy composition. The gradient heterogeneous alloy component manufactured in this work had high bonding strength. The average UTS of MWAAM Ti basic gradient heterogeneous alloy was 793.14 MPa, which was close to MWAAM TC4 alloy and reached approximately 85% of MWAAM TC11 alloy.
•Ti basic bionic gradient heterogeneous alloy was prepared by MWAAM.•The relationship between the degree of elements dilution and microstructure evolution is established.•The wetting state of second solid phase and grain boundary affects the α morphology.•MWAAM-deposited Ti basic bionic gradient heterogeneous alloy shows high strength.
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