Enhanced Magnetic Soft Robotics: Integrating Fiber Optics and 3D Printing for Rapid Actuation and Precision Sensing.

Timely, accurate, and rapid grasping of dynamic change information in magnetic actuation soft robots is essential for advancing their evolution toward intelligent, integrated, and multifunctional systems. However, existing magnetic-actuation soft robots lack effective functions for integrating sensing and actuation. Herein, we demonstrate the integration of distributed fiber optics technology with advanced-programming 3D printing techniques. This integration provides our soft robots unique capabilities such as integrated sensing, precise shape reconstruction, controlled deformation, and sophisticated magnetic navigation. By utilizing an improved magneto-mechanical coupling model and an advanced inversion algorithm, we successfully achieved real-time reconstruction of complex structures, such as 'V', 'N', and 'M' shapes and gripper designs, with a notable response time of 34 ms. Additionally, our robots demonstrate proficiency in magnetic navigation and closed-loop deformation control, making them ideal for operation in confined or obscured environments. This work thus provides a transformative strategy to meet unmet demands in the rapidly growing field of soft robotics, especially in establishing the theoretical and technological foundation for constructing digitized robots.

Spatial variations of fungal community assembly and soil enzyme activity in rhizosphere of zonal Stipa species in inner Mongolia grassland.

Rhizosphere soil fungal and enzyme activities affect the nutrient cycling of terrestrial ecosystems, and rhizosphere fungi are also important participants in the ecological process of vegetation succession, responding to changes in plant communities. Stipa is an excellent forage grass with important ecological and economic value, and has the spatial distribution pattern of floristic geographical substitution. In order to systematically investigate the synergistic response strategies of fungal communities and enzyme activities in the rhizosphere under the vegetation succession. Here we explored the turnover and assembly mechanisms of Stipa rhizosphere fungal communities and the spatial variation of metabolic activity under the succession of seven Stipa communities in northern China grassland under large scale gradients. The results indicated that the composition, abundance and diversity of fungal communities and microbial enzyme activities in rhizosphere soil differed among different Stipa species and were strikingly varied along the Stipa community changes over the geographic gradient. As the geographical distribution of Stipa community changed from east to west in grassland transect, Mortierellomycetes tended to be gradually replaced by Dothideomycetes. The null models showed that the rhizosphere fungal communities were governed primarily by the dispersal limitation of stochastic assembly processes, which showed decreased relative importance from S. grandis to S. gobica. Moreover, the MAT and MAP were the most important factors influencing the changes in the fungal community (richness, ß-diversity and composition) and fungal community assembly, while SC and NP also mediated fungal community assembly processes. These findings deepen our understanding of the responses of the microbial functions and fungal community assembly processes in the rhizosphere to vegetation succession.

Probiotic Formulation VSL#3 Interacts with Mesenchymal Stromal Cells To Protect Dopaminergic Neurons via Centrally and Peripherally Suppressing NOD-Like Receptor Protein 3 Inflammasome-Mediated Inflammation in Parkinson's Disease Mice.

Systemic immunomodulation is increasingly recognized among the beneficial effects of mesenchymal stromal cells (MSCs) in treatment of Parkinson's disease (PD), while the underlying mechanism is not fully understood. With the growing popularity of using probiotics as an adjuvant approach in PD treatment, concerns about the added effects of probiotics have been raised. In addition to the molecular mechanism mediating the neuroprotective effects of MSCs, the combined effects of a probiotic formulation, VSL#3, and MSC infusion were also evaluated in PD mice. The animals were weekly treated with human MSCs (hMSCs) via the tail vein, VSL#3 via the gastrointestinal tract, or their combination six times. hMSCs, VSL#3 alone, and their combination markedly ameliorated the decreased striatal dopamine content, loss of dopaminergic neurons in the substantia nigra, increased levels of proinflammatory cytokines in serum, as well as tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß) mRNAs in striatum and peripheral tissues induced by MPTP. Furthermore, hMSCs, VSL#3, and their combination notably downregulated mRNA expression of NOD-like receptor protein 3 (NLRP3) and caspase-1 in brain and peripheral tissues of PD mice. These results suggest that hMSCs, VSL#3, and their combination prevent neurodegenerative changes in PD mice via anti-inflammatory activities in both the central and peripheral systems, possibly through suppressing the NLRP3 inflammasome. Moreover, two-way analysis of variance (ANOVA) indicated that VSL#3 interacts with hMSCs to attenuate neurodegeneration and inhibit NLRP3 inflammasome-mediated inflammation without altering the effects of hMSCs. Major findings of our study support the usage of probiotic formulation VSL#3 as an adjuvant therapy to hMSC infusion in PD treatment. IMPORTANCE This study provides evidence for the neuroprotective activities of human umbilical cord MSCs from the aspect of anti-inflammation actions. hMSCs inhibit the NLRP3 inflammasome and MPTP-induced inflammation in both brain and periphery to relieve the degenerative changes in dopaminergic neurons in PD mice. Furthermore, as an additional therapeutic agent, probiotic formulation VSL#3 interacts with hMSCs in suppressing the NLRP3 inflammasome as well as the central and peripheral anti-inflammatory effects to exert neuroprotective actions in PD mice without altering the actions of hMSCs, suggesting the potential of VSL#3 as an adjuvant therapy in PD treatment. The findings of the present study give a further understanding of the anti-inflammatory activity and the molecular mechanism for the beneficial effects of MSCs as well as the potential application of probiotic formulation as an adjuvant approach to MSC therapy in PD treatment.

Neuroprotective effects of human umbilical cord mesenchymal stromal cells in PD mice via centrally and peripherally suppressing NLRP3 inflammasome-mediated inflammatory responses.

Mesenchymal stromal cells (MSCs) exhibit beneficial anti-inflammatory effects against Parkinson's disease (PD) via immunomodulatory actions. However, the underlying molecular mechanism remains unclear. This study aimed to investigate the potential neuroprotective effects of MSCs and the possible mechanisms involved by infusing human umbilical cord MSCs (hMSCs) in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mature male C57BL/6 mice. Subsequently, the striatal content of dopamine (DA) and its metabolites, tyrosine hydroxylase (TH)-positive neurons and activated microglia, circulating inflammatory cytokines, gene expression of cytokines, and NOD-like receptor protein 3 (NLRP3) inflammasome molecules were measured using high-performance liquid chromatography, flow cytometry, immunohistochemistry, immunofluorescent staining, and real-time polymerase chain reaction assays, respectively. Infused hMSCs markedly ameliorated the reduction in striatal DA and loss of TH-positive neurons in the substantia nigra of PD mice. The MPTP-induced activation of microglia and increase in tumor necrosis factor-α and interleukin-1ß mRNA expression in the striatum were also attenuated by hMSCs. Furthermore, hMSCs completely reversed the elevated pro-inflammatory cytokine levels in the serum and mRNA expression of cytokines in the peripheral organs of PD mice. Moreover, hMSCs significantly inhibited the expression of caspase-1 and NLRP3 of the NLRP3 inflammasome in both the central and peripheral organs at mRNA level. These data suggest that hMSCs protect dopaminergic neurons in PD mice by suppressing both the central and peripheral inflammatory responses, probably by inhibiting the NLRP3 inflammasome. However, the animals in our study only received several MSC infusions, and the effects of infused MSCs over extended periods on the NLRP3 inflammasome need to be investigated in future studies.

The different variant allele frequencies of type I/type II mutations and the distinct molecular landscapes in CALR-mutant essential thrombocythaemia and primary myelofibrosis.

OBJECTIVE: Calreticulin (CALR) mutations have been identified as driver mutations in a quarter of patients with essential thrombocythaemia (ET) and primary myelofibrosis (PMF), which are subgroups of myeloproliferative neoplasms (MPNs). A 52-bp deletion (type I mutation) and a 5-bp insertion (type II mutation) are the most frequent variants. To better understand the impact of different CALR mutant variants, with or without nondriver mutations, on the clinical subtypes of MPN needs further investigation. METHODS: The clinical characteristics, laboratory parameters and genetic mutation statuses were analysed in a cohort of 77 MPN patients with CALR mutations (ET = 24, prePMF = 33, and overt PMF = 20). Targeted NGS using a 38-gene panel was performed to evaluate the variant allele frequency (VAF) of CALR type I/type II mutations and assess the molecular landscape of nondriver gene mutations. RESULTS: A lower VAF of type I vs. type II was observed in CALR-mutant ET, prePMF and overt PMF, and a higher frequency of type I vs. type II was found in CALR-mutant overt PMF. Additional somatic mutations were indicated to be useful in understanding the pathogenesis of MPN. In this study, the mutation landscape was more complex in overt PMF than in ET or in prePMF. Mutations in epigenetic regulators (ASXL1, EZH2 and TET2) were more common in overt PMF. CONCLUSIONS: The two different subtypes of CALR mutations may have different impacts on MPN. A lower VAF of CALR type I indicates a greater contribution to disease progression in MPN, and increased nondriver mutations may be important in myelofibrosis progression.

[The Effect of si-PKM2 on Proliferation and Apoptosis of Acute Leukemic Cells and Its Molecular Mechanism].

OBJECTIVE: To investigate the effect of glycolytic enzyme pyruvate kinase type 2 (PKM2) on the proliferation and apoptosis of human leukemia HL-60 cells. METHODS: si-PKM2 plasmid was transfected into HL-60 cells (set as si-PKM2 group), and blank vector transfected cells were set as control group (si-Ctl group). The expression levels of PKM2 mRNA and protein in si-Ctl group and si-PKM2 group were detected by RT-qPCR and Western blot. CCK-8 cell detection kit was used to detect the proliferation ability of the cells in the two groups. Flow cytometry was used to detect the changes of cell cycle and apoptosis. Western blot and RT-qPCR were used to detect the changes of p-Akt and p-mTOR protein levels in PI3K/Akt/mTOR signaling pathway and the changes of glycolysis-related mRNA levels of the cells in the two groups. The changes in glucose consumption and lactic acid production of the cells were assayed. Over expressed PKM2, HL-60 cells were treated with PI3K inhibitor LY294002 or galactose, the changes in cell proliferation ability, cell cycle and apoptosis, as well as changes in glucose consumption and lactic acid production were detected. RESULTS: Interfered by si-PKM2, mRNA and protein levels of PKM2 in si-PKM2 group significantly decreased, and proliferation ability of the cells was also reduced (P<0.05). After PKM2 knockdown, the cells were significantly blocked at G1 phase, and cell apoptosis was obviously induced (P<0.05). p-Akt and p-mTOR levels were lower in si-PKM2 group than those in si-Ctl group. The glucose consumption and lactic acid production significantly decreased in si-PKM2 cells. Overexpressed PKM2, HL-60 cells were treated with PI3K inhibitor LY294002. The glucose consumption and lactate acid production induced by overexpressed PKM2 were reduced. Overexpressed PKM2, HL-60 cells showed no significant changes in cell proliferation, cycle and apoptosis when cultured with galactose. CONCLUSION: PKM2 knockdown can inhibit the proliferation and induce apoptosis of HL-60 cells, and its molecular mechanism may be related to the PKM2-mediated PI3K/Akt/mTOR-glycolysis, which suggesting that PKM2 may serve as a molecular target for the prevention and treatment of leukemia.

HNRNPH1 Is a Novel Regulator Of Cellular Proliferation and Disease Progression in Chronic Myeloid Leukemia.

RNA binding proteins act as essential modulators in cancers by regulating biological cellular processes. Heterogeneous nuclear ribonucleoprotein H1 (HNRNPH1), as a key member of the heterogeneous nuclear ribonucleoproteins family, is frequently upregulated in multiple cancer cells and involved in tumorigenesis. However, the function of HNRNPH1 in chronic myeloid leukemia (CML) remains unclear. In the present study, we revealed that HNRNPH1 expression level was upregulated in CML patients and cell lines. Moreover, the higher level of HNRNPH1 was correlated with disease progression of CML. In vivo and in vitro experiments showed that knockdown of HNRNPH1 inhibited cell proliferation and promoted cell apoptosis in CML cells. Importantly, knockdown of HNRNPH1 in CML cells enhanced sensitivity to imatinib. Mechanically, HNRNPH1 could bind to the mRNA of PTPN6 and negatively regulated its expression. PTPN6 mediated the regulation between HNRNPH1 and PI3K/AKT activation. Furthermore, the HNRNPH1-PTPN6-PI3K/AKT axis played a critical role in CML tumorigenesis and development. The present study first investigated the deregulated HNRNPH1-PTPN6-PI3K/AKT axis moderated cell growth and apoptosis in CML cells, whereby targeting this pathway may be a therapeutic CML treatment.

Strain Transfer Characteristics of Multi-Layer Optical Fiber Sensors with Temperature-Dependent Properties at Low Temperature.

Optical fiber sensors have been potentially expected to apply in the extreme environment for their advantages of measurement in a large temperature range. The packaging measure which makes the strain sensing fiber survive in these harsh conditions will commonly introduce inevitable strain transfer errors. In this paper, the strain transfer characteristics of a multi-layer optical fiber sensing structure working at cryogenic environment with temperature gradients have been investigated theoretically. A generalized three-layer shear lag model incorporating with temperature-dependent properties of layers was developed. The strain transfer relationship between the optical fiber core and the matrix has been derived in form of a second-order ordinary differential equation (ODE) with variable coefficients, where the Young's modulus and the coefficients of thermal expansion (CTE) are considered as functions of temperature. The strain transfer characteristics of the optical sensing structure were captured by solving the ODE boundary problems for cryogenic temperature loads. Case studies of the cooling process from room temperature to some certain low temperatures and gradient temperature loads for different low-temperature zones were addressed. The results showed that different temperature load configurations cause different strain transfer error features which can be described by the proposed model. The protective layer always plays a main role, and the optimization geometrical parameters should be carefully designed. To verify the theoretical predictions, an experiment study on the thermal strain measurement of an aluminum bar with optical fiber sensors was conducted. LUNA ODiSI 6100 integrator was used to measure the Rayleigh backscattering spectra shift of the optical fiber at a uniform temperature and a gradient temperature under liquid nitrogen temperature zone, and a reasonable agreement with the theory was presented.

A versatile facility for investigating field-dependent and mechanical properties of superconducting wires and tapes under cryogenic-electro-magnetic multifields.

To investigate the field-dependent and mechanical properties of superconducting wires and tapes as a function of cryogenic temperature, transport current, and magnetic field, we designed and constructed a versatile facility capable of providing cryogenic-electro-magnetic multifields. The facility comprises several relatively independent systems to acquire multiple fields and explore various properties for superconductors. A superconducting racetrack magnet is manufactured to generate a transverse background field up to 3.5 T in a relatively large space of a homogeneous region of ∅200 mm × H 150 mm. A cryogenic system consisting of a vacuum Dewar vessel with a visible window cooled by two Gifford-McMahon (GM) cryocoolers for providing refrigeration was built to accommodate the background magnet and testing devices, in which one GM cryocooler cools the magnet at an operation temperature of about 4 K and the other maintains a cryogenic environment for specimens in conduction mode with the cryocooler head directly contacting the fixtures. The continuous variations of temperature (4-293 K) and transport current (0-1000 A) in the superconducting wires and tapes that were tested are, respectively, implemented by an integration differentiation temperature control with an optional temperature sweep rate and a DC high-power supply. Most prominently, the facility can measure the field-dependent and mechanical properties for superconducting wires and tapes, which is implemented by a mechanical loading and measuring system equipped with a universal testing machine possessing a specific design of widening and heightening size and a noncontact digital image correlation method with a high-speed, high-resolution CCD camera for real-time recording and full-field deformation of specimens. The preliminary results of tests verify the multifield functionalities of the versatile facility and illustrate the performance of the facility for studying the properties of superconducting wires and tapes as a function of magnetic field, cryogenic temperature, transport current, and mechanical loading.

The Long Noncoding RNA MEG3 and its Target miR-147 Regulate JAK/STAT Pathway in Advanced Chronic Myeloid Leukemia.

BACKGROUND: Long non-coding (lnc) RNAs plays an important role in chronic myeloid leukemia (CML). In this study, we aimed to uncover the mechanism of the lncRNA maternally expressed 3 (MEG3) and its target microRNA-147 (miR-147) in CML. METHODS: Sixty CML patients and 10 healthy donors were included in the study. The methylation of MEG3 and miR-147 promoter was determined by methylation-specific PCR. The relationship of MEG3 and miR-147 was explored by luciferase assay. The interactions of proteins were studied by RNA pull-down assay, RNA immunoprecipitation and co-immunoprecipitation. FINDINGS: Patients in accelerated phase CML (CML-AP) and blast phase CML (CML-BP) showed lower expressions of MEG3 and miR-147 and higher expressions of DNMT1, DNMT3B, MBD2, MECP2 and HDAC1 compared to the controls. These patients also showed a higher degree of methylation of MEG3 and miR-147 while there was a reduction after chidamide treatment. Furthermore, the overexpression of MEG3 and miR-147 inhibited cell proliferation both in vivo and in vitro, promoted apoptosis and decreased the expressions of DNMT1, DNMT3A, DNMT3B, MBD2, HDAC1 and MECP2. We also found MEG3 interacted with DNMT1, JAK2, STAT3, HDAC1, and TYK2, and JAK2 was bound to STAT3, STAT5 and MYC. More interestingly, JAK2 was bound to TYK2 by the bridge of MEG3. INTERPRETATION: LncRNA MEG3 and its target miR-147 may serve as a novel therapeutic target for CML blast crisis, and chidamide might have a potential clinical application in treating CML blast crisis.

Association between methylation of tumor suppressor gene SOCS1 and acute myeloid leukemia.

Suppressor of cytokine signaling­1 (SOCS1) is a widely recognized tumor suppressor gene. Silencing of SOCS1 expression as a result of promoter methylation is associated with occurrence and development of solid tumors such as liver, cervical and pancreatic cancer. However, the association between SOCS1 gene methylation and acute myeloid leukemia (AML) has not been well explored. In the present study, we examined whether gene expression and methylation status of SOCS1 was altered in AML, and whether this was related to disease occurrence and development. To assess this hypothesis, we analyzed SOCS1 in four groups of AML patients: i) Initial treatment group (IT); ii) relapsed/refractory group (RR); iii) remission group (RE); and iv) normal control group (NC). We also used leukemia cell lines U937 and THP­1 to study the underlying molecular mechanism of SOCS1 in AML, mainly the JAK2/STAT pathway. We used several techniques such as quantitative PCR (qPCR), methylation­specific PCR (MS­PCR), western blotting, flow cytometry and cell transfection techniques to analyze the expression and methylation status of SOCS1. We found that the SOCS1 gene methylation rate in the IT and RR groups was significantly higher than that in the RR and NC groups (48, 80 vs. 0 and 0%, respectively). Furthermore, mRNA and protein expression was significantly lower in the IT and RR groups when compared to the RE and NC groups. We also found that the JAK2/STAT signaling pathway was negatively affected by SOCS1. SOCS1 gene methylation caused gene silencing of SOCS1 which overcame the suppression of the downstream JAK2/STAT signaling pathway by SOCS1, and promoted the growth and proliferation of AML cells.

[Clinical Analysis of 12 cases of Systemic Lupus Erythematosus Associated with Thrombotic Thrombocytopenic Purpura].

OBJECTIVE: To investigate the clinical manifestations, treatment strategies and outcomes of 12 patients with systemic lupus erythematosus (SLE) associated with thrombotic thrombocytopenic purpura(TTP). METHODS: The clinical data from 12 cases of SLE associated with TTP admitted in the Second Hospital of Hebei Medical University from January 2002 to August 2015 were retrospectively analyzed. RESULTS: 12 cases of SLE associated with TTP included 11 females and 1 male, their median age was 34.5 years old, among them 5 cases of TTP were diagnosed during the treatment of SLE, 7 cases of TTP were comfirmed together with SLE on admission. The hemolytic anemia, thrombocytopenia and neurological deficits appeared in all the patients, the renal impairment was observed in 10 cases, the schistocytes of peripheral blood smears (>1%) were present in 9 cases, a severely reduction of ADAMTS 13 activity (<5%) with inhibitor-positive had been demonstrated in 5 cases, all of the 12 patients were treated with glucocorticoid, and 11 cases were treated in combination with other drug(10 cases combined with cytotoxics, 1 case with intravenous gamma globulin, 1 case with rituximab), plasma exchange were used in 10 cases, and 2 cases died, 2 cases without receiving plasma exchange all died, renal damage was observed in all the dead patients. CONCLUSION: Clinical manifestation and repeated examinations of peripheral blood smears are helpful for early diagnosis of SLE associated with TTP, the plasma exchange combined with glucocortcoids is an effective treatment method, the renal impairment may be a risk factor related with poor prognosis.

Research on the epigenetic regulation mechanism of the PTPN6 gene in advanced chronic myeloid leukaemia.

PTPN6, a tyrosine phosphatase protein, plays a negative role in cell signal transduction and is negatively correlated with tumour formation and growth. However, epigenetic regulation mechanism of the PTPN6 gene in advanced chronic myeloid leukaemia (CML) remains unclear. This study investigated bone marrow or blood samples from 44 CML patients and 10 healthy volunteers. KCL22 and K562 cells were cultured and treated with demethylation drugs and histone deacetylase inhibitors. Real time quantitative polymerase chain reaction (qPCR), methylation-specific PCR, bisulfite sequencing PCR, Western blotting, co-immunoprecipitation and chromatin immunoprecipitation (ChIP) was performed. PTPN6 was down-regulated in cell lines and patients with advanced phase CML, whereas DNMT1, DNMT3A, MECP2, MBD2 and HDAC1 were up-regulated. Treatment with 5-azacytidine, decitabine, sodium valproate and LBH589 increased PTPN6 expression, but decreased that of DNMT1, DNMT3A, MECP2, MBD2 and HDAC1. Immunoprecipitation and mass spectrometry showed that HDAC1 combined directly with PTPN6. ChIP-seq showed that HDAC1 did not combine with the promoter region of PTPN6, while MAPK, AKT, STAT5, JAK2 and MYC promoter regions all combined with HDAC1. PTPN6 is associated with progression of CML. Low expression level of PTPN6 was associated with DNA methylation and regulated by histone acetylation. HDAC1 participates in the regulation of PTPN6.

Magnetic Driving Flowerlike Soft Platform: Biomimetic Fabrication and External Regulation.

Nature-inspired actuators that can be driven by various stimuli are an emerging application in mobile microrobotics and microfluidics. In this study, a soft and multiple-environment-adaptive robotic platform with ferromagnetic particles impregnated in silicon-based polymer is adopted to fabricate microrobots for minimally invasive locomotion and control interaction with their environment. As an intelligent structure of platform, the change of its bending, deformation, and flapping displacement is rapid, reversible, and continuously controllable with sweeping and multicycle magnetic actuation. The bending angle of the soft platform (0.2 mm in thickness and 8.5 mm in length) can be deflected up to almost 90° within 2.7 s. Experiments demonstrated that the flexible platform of human skin-like material in various shapes, that is, flowerlike shapes, can transport a cargo to targeted area in air and a variety of liquids. It indicates excellent magnetic-actuation ability and good controllability. The results may be helpful in developing a magnetic-driven carrying platform, which can be operated like a human finger to manipulate biological objects such as single cells, microbeads, or embryos. Especially, it is likely to be used in harsh chemical and physical circumstances.

A Parametric Study on Overband Radial Build for a REBCO 800-MHz Insert of a 1.3-GHz LTS/HTS NMR Magnet.

A high-resolution 1.3-GHz/54-mm low-temperature superconducting/high-temperature superconducting (HTS) nuclear magnetic resonance magnet (1.3 G) is currently being built at Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology. One of its key components is an 800-MHz HTS insert (H800) comprising three nested coils. Each coil is a stack of double-pancake coils wound with 6-mm-wide 75-µm-thick REBCO tape. For this H800 generating its self-field of 18.6 T and being exposed to a total field as high as 30.5 T, overbanding each pancake coil is necessary to keep the conductor strain at < 0.6%. Although electromagnetic and mechanical details of the H800 had been considered during its design stage, a parametric study on the overband radial build considering winding tension effect should further confirm the results of our previous analysis. Thus, in this paper, based on Maxwell's equations and the equilibrium equations for mechanical deformation, we examine stress levels that the H800 experiences as H800 undergoes winding-energizing sequences during operation at 1.3 GHz. We also discuss the effects of overband radial build and winding tension on conductor stress in each coil. Finally, based on this analysis, we may further optimize the stainless-steel overbanding and winding tension on each H800 coil.

Impacts of K562 cells towards activities of Toll-like receptor pathway of human mesenchymal stem cell-bone marrow.

The study aim was to investigate the impacts of K562 cells towards the activities of Toll-like receptor pathway of human mesenchymal stem cell-bone marrow (HMSC-bm). The in vitro co-culture of HMSC-bm and K562 cells was set as the experiment group (HMSC-bm + K562), the HMSC-bm cultured alone was set as the control group (HMSC-bm), the expressions of six interested genes and their proteins, namely MyD88, P38, NF-κB, TAB1, TLR3 and TBK1, of the Toll -like receptor signaling pathway were detected and compared, as well as the secretions of such cytokines as IL-6, IL-8, TNF-α and IFN-α in the cell supernatant, which were regulated by the Toll-like receptor pathway. The expressions of MyD88, P38, TAB1 and TLR3 of the HMSC-bm + K562 group were higher than the HMSC-bm group, while that of TBK1 was lower, and the NF-κB expression showed no significant difference between the two groups (P > 0.05). Compared with the HMSC-bm group, the supernatant of HMSC-bm + K562 group exhibited the higher secretion levels of IL-6 and IL-8, while that of IFN-α was just contrary, and the differences were significant (P < 0.05). The secretion levels of TNF-α within the two groups were not significantly different (P > 0.05). The co-culture of K562 and HMSC-bm could induce the activity changes of Toll-like receptor pathway of HMSC-bm, which was beneficial towards the proliferation of K562 cells.

Effects of cold-treatment and strain-rate on mechanical properties of NbTi/Cu superconducting composite wires.

During design and winding of superconducting magnets at room temperature, a pre-tension under different rate is always applied to improve the mechanical stability of the magnets. However, an inconsistency rises for superconductors usually being sensitive to strain and oversized pre-stress which results in degradation of the superconducting composites' critical performance at low temperature. The present study focused on the effects of the cold-treatment and strain-rate of tension deformation on mechanical properties of NbTi/Cu superconducting composite wires. The samples were immersed in a liquid nitrogen (LN2) cryostat for the adiabatic cold-treatment, respectively with 18-hour, 20-hour, 22-hour and 24-hour. A universal testing machine was utilized for tension tests of the NbTi/Cu superconducting composite wires at room temperature; a small-scale extensometer was used to measure strain of samples with variable strain-rate. The strength, elongation at fracture and yield strength of pre-cold-treatment NbTi/Cu composite wires were drawn. It was shown that, the mechanical properties of the superconducting wires are linearly dependent on the holding time of cold-treatment at lower tensile strain-rate, while they exhibit notable nonlinear features at higher strain-rate. The cold-treatment in advance and the strain-rate of pre-tension demonstrate remarkable influences on the mechanical property of the superconducting composite wires.