Influence of vacuoles with gas–liquid inclusions on the thermobaric destruction conditions of natural quartz under dynamic heating in an RF-TICP torch system

In the present work,the turbulent mixing process of a polydisperse quartz particle flow with a plasma stream generated by a radio-frequency(RF)inductively coupled plasma torch was numerically studied.The thermobaric stress in the quartz particles under dynamic heating in a heterogeneous plasma flow was determined by a two-stage approximation approach.The effect of the presence of vacuoles in natural quartz on the particle thermobaric destruction conditions was studied.It was found that the equivalent thermal and baric stresses in quartz particles may significantly increase in the presence of vacuoles within a small gas volume fraction.The influence of the regime and energetic working conditions of an RF inductively coupled plasma torch system on the particle thermobaric destruction conditions was examined,and a recommendation was given to promote the degree of thermobaric destruction of quartz particles,which is of substantial importance for improving the overall enrichment efficiency of quartz concentrates.

Molecular Cloning,Bioinformatics Analysis and Transcriptional Expression of Virulence-related Gene(exsA)of Vibrio alginolyticus

[Objectives]The purpose was to investigate the function and mechanism of exsA gene in type III secretion system of Vibrio alginolyticus.[Methods]The full length of exsA was cloned using molecular biology techniques to analyze its biological information.Fluorescence quantitative PCR technology was used to analyze the expression of exsA after different media stress.[Results]The exsA gene contains an open reading frame(ORF)of 861 bp,encoding 286 amino acids.The physico-chemical analysis shows that the molecular structural formula is C1442H2267N393O441S12,the theoretical molecular weight is 32.549 kD,the theoretical pI value is 6.0,and the protein is non-hydrophilic and unstable.The gene does not contain a transmembrane region,and there is no obvious signal peptide.The prediction result of protein subcellular localization shows that the protein is inside the cell.The deduced amino acid sequence and constructed phylogenetic tree show that V.alginolyticus has a close relationship with Vibrio antiquarius.The qPCR results show that the expression level of exsA in different media is different,highest in TSB medium containing bile salts,followed by DMEM medium,and lowest in ordinary TSB medium.[Conclusions]The gene sequence,molecular structure and isoelectric point of exsA,as well as its expression in three different media were obtained.

Irisin Attenuates Osteoarthritis by Inhibiting Apoptosis of Osteocytes Through Activating Erk Signaling Pathway

Osteoarthritis(OA)is an inflammatory disease involving the joints that is prevalent in the global aging population.The purpose of this study is to determine whether irisin can attenuate osteoarthritis(OA)progression in anterior cruciate ligament transection(ACLT)mice models and the mechanism of irisin therapy effect on OA by increase the resistance of apoptosis in MLO-Y4 cells induced by mechanical stretch in vitro.Methods For in vivo study,3-month-old male C57BL/6 J mice were randomized to three groups,sham-operated,anterior cruciate ligament transection(ACLT)-operated treated with vehicle,and ACLT-operated treated with irisin by intraperitoneal injection once a week.Cartilage erosion was observed by HE staining.Osteoarthritis Research Society International(OARSI)scores were evaluated according to the safranin O stai-ning.The microstructure of tibia cortical bone,trabecular bone,and subchondral bone was analyzed by micro-CT and the bone histomorphometry has been administrated including mineral apposition rate(MAR).Edu staining and cck-8 were used for the detection of the proliferation of MLO-Y4 cells.For mechanical stress,cells were seeded on the collagen-I coated chamber subjected with a peak biaxial stretch of 20%at 1 Hz for 16 hours to induce apoptosis.Flow cytometry was used for the detection of apoptosis and cell cycle.TUNNEL was used for staining the apoptotic cells and rt-PCR was applied for quantifying the expression of mRNA such as Bax,Bcl-2,SOST,c-myc,Opg.Western blot was utilized to confirm the mechanism of how irisin decrease the osteocyte apoptosis.Results In vivo,irisin can attenuate articular cartilage degeneration.Irisin maintains the proportion of hyaline cartilage and calcified cartilage and keep fewer cartilage erosions in ACLT-operated mice.For immunohistochemical(IHC)staining,irisin reduced the expression of caspase3,Bax and matrix metalloproteinase-13 in both cartilage and subchondral bone.Irisin-treated ACLT group shows higher Trabecular number(Tb.N)and bone volume fraction(BV/TV)compared to the vehicle-treated ACLT group.In vitro, irisin significantly increased the proliferation of MLO-Y4 cells detected by Edu and Ki67 staining,and irisin can protect the cells from both mechanical stretchinduced apoptosis detected by FITC-PI flow cytometry and maintain the cell activity by regulating the expression of Bax,Bcl-2,and c-myc.Transcriptome sequencing shows that irisin significantly activates the MAPK signaling pathway and we confirm the result by western blot:irisin effectively activates the Erk signaling pathway through phosphorylation and has a certain activation effect on p38 signaling pathway,no activation was observed for FAK signaling pathway.Conclusions Irisin can attenuate the progression of OA by decrease the apoptosis of osteocyte,which can improve the microarchitecture of subchondral bone.Erk pathway activation plays an important role in reducing the apoptosis of osteocyte.

Association Between Knee Alignment,Disease Severity and Subchondral Trabecular Bone Microarchitecture in Patients with Knee Osteoarthritis

Objective Most patients with knee osteoarthritis(OA)have alignment deformity with the change of Hip-knee-ankle(HKA)angle.The knee alignment influences load distribution at the tibial plateau.Meanwhile,change of subchondral trabecular bone microstructure is related to load bearing and OA progression.However,the relationship between knee alignment on the changes of subchondral trabecular bone microstructure and OA severity have been poorly investigated.The main goal of this work was to investigate variation in tibial plateaus subchondral trabecular bone microstructure in knee OA patients and their association with the severity of OA with the change of knee alignment.Methods Seventy-one knee OA patients planning to undergo total knee arthroplasty were enrolled in this study.The HKA angle and OA disease severity(OARSI score,compartment-specific Kellgren-Lawrence(K-L)grade and OARSI Atlas grade)based on full-leg standing posteroanterior radiographs were evaluated preoperatively in all patients.The tibial plateau collected during surgery was first used for micro-computed tomography(μCT)to analyze the subchondral trabecular bone microstructures,and then used for pathological sections to analyze cartilage degeneration(OARSI score).Pearson and spearman correlations were used to examine linear relationships between knee alignment,OA disease severity and subchondral trabecular bone microstructure.Patients were then divided into group I(HKA angle exceeds 0°in the valgus direction),group II(varus angle<10°)and group III(varus angle≥10°).The differences in subchondral trabecular bone microstructural parameters between the three groups were analyzed by the one-way ANOVA with a post hoc Tukey test.Results HKA angle was significantly correlated with all tibial plateau subchondral trabecular bone microstructure parameters.Regardless of the medial or lateral tibia,HKA angle was most strongly correlated with bone volume fraction(BV/TV),M:(r=0. 613,P<0.01);L:(r=-0.490,P<0.01).In addition,for the media-to-lateral ratios(M:L)of the subchondral trabecular bone microstructure parameters,the HKA angle is positively correlated with M:L BV/TV(r=0.658,P<0.01),M:L trabecular number(Tb.N)(r=0.525,,P<0.01),M:L trabecular thickness(Tb.Th)(r=0.636,P<0.01),and negatively correlated with M:L trabecular separation(Tb.Sp)(r=-0.636,P<0.01)and M:L Specific Bone Surface(BS/BV)(r=-0.792,P<0.01).The BV/TV,Tb.N,and Tb.Th of the medial tibia were sequentially incremented in the order of groupⅠ,Ⅱ,Ⅲof knee alignment,while the Tb.Sp and BS/BV were decreased in this order.The lateral tibia is the opposite.In addition,most of the severity indices of OA are associated with subchondral trabecular bone microstructures,of which OARSI score and BV/TV in medial tibia are the most relevant(r=0.787,P<0.01).HKA angle is significantly correlated with all OA severity grades in medial compartment,but only with OARSI score and Bone sclerosis grade in lateral compartment.Conclusions Tibial plateau subchondral trabecular bone microarchitecture is associated with the HKA angle and OA severity.With the increase of varus angle and the severity of OA,the subchondral trabecular bone in medial tibia has more obvious sclerosis changes and vice versa,suggesting that knee malalignment may promote abnormal subchondral trabecular bone remodeling by altering joint load distribution,thereby affecting the progression of OA.

In situ self-assembled organoid for osteochondral tissue regeneration with dual functional units

The regeneration of hierarchical osteochondral units is challenging due to difficulties in inducing spatial,directional and controllable differentiation of mesenchymal stem cells(MSCs)into cartilage and bone compartments.Emerging organoid technology offers new opportunities for osteochondral regeneration.In this study,we developed gelatin-based microcryogels customized using hyaluronic acid(HA)and hydroxyapatite(HYP),respectively for inducing cartilage and bone regeneration(denoted as CH-Microcryogels and OS-Microcryogels)through in vivo self-assembly into osteochondral organoids.The customized microcryogels showed good cytocompatibility and induced chondrogenic and osteogenic differentiation of MSCs,while also demonstrating the ability to self-assemble into osteochondral organoids with no delamination in the biphasic cartilage-bone structure.Analysis by mRNA-seq showed that CH-Microcryogels promoted chondrogenic differentiation and inhibited inflammation,while OS-Microcryogels facilitated osteogenic differentiation and suppressed the immune response,by regulating specific signaling pathways.Finally,the in vivo engraftment of pre-differentiated customized microcryogels into canine osteochondral defects resulted in the spontaneous assembly of an osteochondral unit,inducing simultaneous regeneration of both articular cartilage and subchondral bone.In conclusion,this novel approach for generating self-assembling osteochondral organoids utilizing tailor-made microcryogels presents a highly promising avenue for advancing the field of tissue engineering.

Novel self-assembled two-dimensional layered oxide structure incorporated with Au nanoinclusions towards multifunctionalities

Two-dimensional(2D)layered oxides have recently attracted wide attention owing to the strong coupling among charges,spins,lattice,and strain,which allows great flexibility and opportunities in structure designs as well as multifunctionality exploration.In parallel,plasmonic hybrid nanostructures exhibit exotic localized surface plasmon resonance(LSPR)providing a broad range of applications in nanophotonic devices and sensors.A hybrid material platform combining the unique multifunctional 2D layered oxides and plasmonic nanostructures brings optical tuning into the new level.In this work,a novel self-assembled Bi2MoO6(BMO)2D layered oxide incorporated with plasmonic Au nanoinclusions has been demonstrated via one-step pulsed laser deposition(PLD)technique.Comprehensive microstructural characterizations,including scanning transmission electron microscopy(STEM),differential phase contrast imaging(DPC),and STEM tomography,have demonstrated the high epitaxial quality and particle-in-matrix morphology of the BMO-Au nanocomposite film.DPC-STEM imaging clarifies the magnetic domain structures of BMO matrix.Three different BMO structures including layered supercell(LSC)and superlattices have been revealed which is attributed to the variable strain states throughout the BMO-Au film.Owing to the combination of plasmonic Au and layered structure of BMO,the nanocomposite film exhibits a typical LSPR in visible wavelength region and strong anisotropy in terms of its optical and ferromagnetic properties.This study opens a new avenue for developing novel 2D layered complex oxides incorporated with plasmonic metal or semiconductor phases showing great potential for applications in multifunctional nanoelectronics devices.

Enhanced bone regeneration via endochondral ossification using Exendin-4-modified mesenchymal stem cells

Nonunions and delayed unions pose significant challenges in orthopedic treatment,with current therapies often proving inadequate.Bone tissue engineering(BTE),particularly through endochondral ossification(ECO),emerges as a promising strategy for addressing critical bone defects.This study introduces mesenchymal stem cells overexpressing Exendin-4(MSC-E4),designed to modulate bone remodeling via their autocrine and paracrine functions.We established a type I collagen(Col-I)sponge-based in vitro model that effectively recapitulates the ECO pathway.MSC-E4 demonstrated superior chondrogenic and hypertrophic differentiation and enhanced the ECO cell fate in single-cell sequencing analysis.Furthermore,MSC-E4 encapsulated in microscaffold,effectively facilitated bone regeneration in a rat calvarial defect model,underscoring its potential as a therapeutic agent for bone regeneration.Our findings advocate for MSC-E4 within a BTE framework as a novel and potent approach for treating significant bone defects,leveraging the intrinsic ECO process.