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Abstract: Silica carbide modified carbon cloth laminated C–C composites have been successfully joined to lithium–aluminum–silicate (LAS) glass–ceramics using magnesium–aluminum–silicate (MAS) glass–ceramics as interlayer by vacuum hot-press technique. The microstructure, mechanical properties and fracture mechanism of C–C/LAS composite joints were investigated. SiC coating modified the wettability between C–C composites and LAS glass–ceramics. Three continuous and homogenous interfaces (i.e. C–C/SiC, SiC/MAS and MAS/LAS) were formed by element interdiffusions and chemical reactions, which lead to a smooth transition from C–C composites to LAS glass–ceramics. The C–C/LAS joints have superior flexural property with a quasi-ductile behavior. The average flexural strength of C–C/LAS joints can be up to 140.26MPa and 160.02MPa at 25°C and 800°C, respectively. The average shear strength of C–C/LAS joints achieves 21.01MPa and the joints are apt to fracture along the SiC/MAS interface. The high retention of mechanical properties at 800°C makes the joints to be potentially used in a broad temperature range as structural components. [Copyright &y& Elsevier]

Abstract: Straight carbon nanotubes (CNTs) were grafted radially onto carbon fibers and they were used to enhance mechanical strength retention rate (i.e. the percentage of mechanical strength after graphitization as that before graphitization) of laminated carbon/carbon (C/C) composites after graphitization. Results show that out-of-plane compression strength and interlaminar shear strength retention rates of C/C composites increase from 34.7% and 42.1% to 76.2% and 84.9% after adding CNTs, showing 120% and 102% improvements. Analyses demonstrate that these great improvements are the result of simultaneous reinforcements to the fiber/matrix (F/M) interface and the matrix provided by the radially grafted CNTs, which can effectively inhibit the microstructure defects such as F/M interface debonding and matrix annular cracking occurred around carbon fiber during graphitization and then greatly increase the mechanical strength of graphitized C/C composites. [Copyright &y& Elsevier]

Abstract: Carbon/carbon (C/C) composites were joined to lithium aluminum silicate (LAS) glass-ceramic using a joining layer consisting of a SiC transition layer and a multilayer of magnesium aluminum silicate (MAS) and LAS glass-ceramic by a two-step technique of pack cementation and hot-pressing sintering. The microstructures of the as-prepared joint were characterized by scanning electron microscopy and energy dispersive spectrometry. The design of the multilayer structure could provide more possibilities for crack propagation to release the stress in the joint. Results of the thermal shock test showed that the average shear strength of the joined samples increased from 17.9MPa to 32.6MPa after 50 thermal cycles between 800°C and room temperature, which was primarily attributed to the toughening effects of microcracks. However, after 30 thermal cycles between 1000°C and room temperature, the average shear strength of the joined samples dropped to 14.2MPa since the crack size was beyond the tolerance of the joint. [Copyright &y& Elsevier]

Abstract: A pneumatic drop-on-demand (DOD) system has been applied to solder complex and dense interconnects of modern micro electronic devices. Initial parameters of uniform droplets were first measured. Then influences of experiment parameters, such as the crucible temperature, the substrate temperature and the droplet velocity on spread of solder droplets, were investigated experimentally and theoretically. The results showed that effects of impact velocity on the spreading could be negligible and the solder spreading process was driven by capillary forces because of the low Weber (We) number of depositing droplet. The influence of initial droplet temperature on the droplet spreading was not regular. The contact diameter of solder droplets on copper substrate increased when the substrate temperature increased from 443K to 493K. At last, copper cables were successfully soldered to pins of a flexible circuit using the direct solder deposition and re-melting process. The soldering results showed the feasibility of the data-driven soldering technique using the pneumatic DOD deposition technology. [Copyright &y& Elsevier]

Abstract: Straight carbon nanotubes (CNTs) were grafted radially onto carbon fibers to produce hybrid materials that were used to reinforce carbon/carbon (C/C) composites. Mechanical property tests indicated that these C/C composites have improvements in out-of-plane and in-plane compressive strengths and interlaminar shear strength of 275%, 138% and 206%, respectively. They also have a large decrease in the anisotropy of mechanical properties, compared with pure C/C composites. This great improvement is the result of the simultaneous reinforcements to the fiber/matrix interface and the matrix provided by the grafted CNTs. [Copyright &y& Elsevier]

Abstract: Metal micro-droplet deposition manufacture technology has attracted wide interest for potential application in micro-structure fabrication. In order to fabricate functional metal components by sequentially depositing molten metal droplets on substrate layer by layer, the perfect overlapping and bonding strength among droplets have to be obtained. In this paper, the influence of scanning step on overlapping of droplets was investigated, and the critical overlapping condition of droplets was calculated by analyzing the relationship of the shape parameters of solidified droplet on the substrate. Four kinds overlapping states of adjacent droplets were predicted according to the change of scanning steps: no overlapping, partial overlapping, ideal overlapping and excessive overlapping. On this basis, two simple and effective models were proposed to calculate and predict the optimal scanning steps (W XP and W YL ). The calculation results show that the W XP and W YL were only affected by droplet diameter (D) and solidification angle (θ). Based on this analysis, a pneumatic droplet generator was used to produce uniform molten Sn60–Pb40 alloy droplets with specific diameters (256μm, 400μm and 700μm), and a series of deposition experiments were carried out with different scanning steps on the condition of fixed droplet temperature (270°C) and substrate temperature (90°C). The experimental results show that good overlapping and bonding strength of adjacent droplets could be obtained in deposited lines and layers, and low porosity and high density three-dimensional metal component was fabricated with optimized experimental parameters (W XP and W YL ) according to theoretical models. The work can provide useful theoretical and experimental guide for metal micro-droplet deposition manufacture. [Copyright &y& Elsevier]

Abstract: Using natural gas as carbon source, isotropic and low texture pyrocarbon was fabricated with deposition temperature range from 1450 to 1550°C. The d 002-spacing and crystal size of the pyrocarbon were derived from X-ray diffraction (XRD) and Raman spectroscopy. Fracture surface morphology and texture of the pyrocarbon were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Flexural strength was tested using three points bending test. The analysis results were applied to study the relationship among deposition temperature, microstructure and flexural strength of pyrocarbon. Elevating deposition temperature not only increased the density, crystal size, but also upgraded the texture of the pyrocarbon from isotropic to low texture. It showed that density, crystal size and texture of pyrocarbon significantly influenced its flexural strength. [Copyright &y& Elsevier]

Abstract: A 2D axisymmetric model has been proposed to study the mechanism of the droplet generation by using a pneumatic drop-on-demand (DOD) generator. A proprietary pneumatic DOD generator was also applied to conduct droplet generation experiments. The validity of the proposed model was verified through the simulation results of droplet pattern, breakup length distance and droplet diameter, which were in good agreement with the experimental ones. Theoretical studies were conducted to characterize the metal droplet generation using pneumatic DOD technique. Theoretical analyses show that metal droplets break away from jets in front of the sphere ends due to the increase of the capillary disturbance at a very small Ohnesorge number (Oh<0.01). This capillary disturbance is caused by the action of surface tension. Shapes of droplets do not significantly change because of the relatively low pressure inside droplets. The droplet diameter decreases when the nozzle diameter decreases to 100μm, while the ratio of droplet diameter to nozzle diameter increases rapidly. An external disturbance with high frequency should be introduced to accelerate the metal jet breakup for further decreasing the droplet size. This work offers a useful guide for choosing appropriate parameters to generate metal droplets using pneumatic DOD technique. [Copyright &y& Elsevier]

The deposition of metal droplets has been attracted wide interests for potential applying in microstructures fabrication. A uniform droplet generator with image acquiring system and droplet temperature measuring system was established. A coupling analysis method on combination of droplets dynamic and thermal models was proposed. Effect of experimental parameters on deflected trajectory and the temperature history of the uniform droplets was investigated. The measured trajectory and temperature history agreed well with the predicted results, indicating the validity of the proposed analysis method. The predicted results with different experimental parameters showed that the deflected trajectories and thermal histories of the droplets with diameters close to 100 μm or less were strongly dependent on their sizes. Small droplets had a narrow deposition length for obtaining parts with good metallurgical bonding. The predicted results also showed that it was effective in controlling the deflected trajectories and thermal histories of droplets by adjusting the pressure when it was low. At last, micro alloy tubes with good metallurgical bonding were obtained using 50 μm diameter nozzle when the experimental parameters were chosen according to theoretical models. The deposited results show that proper parameters for microstructures deposition can be obtained according to the proposed analysis method. [ABSTRACT FROM AUTHOR]

A SiO 2 -Nd 2 O 3 /Si-SiC-MoSi 2 coating was proposed to repair the damaged SiC coated C/C composites by laser cladding. Laser ablation was performed to evaluate the effect of coating repair. Results showed that the preparation of the SiO 2 -Nd 2 O 3 outer layer could improve the laser ablation resistance of the specimens by weakening heat accumulation and enhancing heat consumption, which reduced the maximum temperature by 261.99 K and 694.75 K during ablation under 300 W and 500 W for 7 s. The growth of the ablative products, including the Si nanowires and SiO x spherical particles, was based on vapor deposition and oxide-assisted growth mechanism. • The damaged SiC coated C/C composites was repaired by laser cladding technique. • A SiO 2 -Nd 2 O 3 /Si-SiC-MoSi 2 coating system was proposed for repair. • The laser ablation resistance was improved by preparing the SiO 2 -Nd 2 O 3 outer layer. • The ablation temperature was reduced significantly by the SiO 2 -Nd 2 O 3 outer layer. • Both heat accumulation and consumption were influenced by the SiO 2 -Nd 2 O 3 outer layer. [ABSTRACT FROM AUTHOR]

Abstract: The effects of aging processes on the properties and microstructure of Cu–0.3Cr–0.15Zr–0.05Mg lead frame alloy were investigated. Aging precipitation phase was dealt with by transmission electronic microscope (TEM). After solid solution was treated at 920°C and aged at 470°C for 4h, the fine precipitation of an ordered compound CrCu2(Zr, Mg) is found in copper matrix as well as fine Cr and Cu4Zr. Along the grain boundary, there are larger chromium. The hardness and electrical conductivity can reach 109HV and 80% IACS, respectively. Sixty percent cold-rolled deformation prior to aging at 470°C enhances the hardness of the alloy. The coherent precipitates Cr in copper matrix and the dislocations pinned by the fine precipitates are responsible for maximum strengthening of the alloy. So the hardness 165HV and electrical conductivity 79.2% IACS are available. [Copyright &y& Elsevier]

[Display omitted] • The damaged SiC coated C/C composites was repaired successfully. • A Mo-modified Si-SiC coating was prepared on C/C composites by laser-inducing. • The free Si of the Si-SiC coating was decreased significantly by Mo-modification. • The interface bonding of the coating modified with 10 wt% Mo was the best. • The oxidation resistance of the repaired coating was improved significantly. As the thermal structural component of aircraft, SiC coated C/C composites will fail and cause catastrophic consequences once the SiC anti-oxidation coating is damaged. Therefore, it is extremely important to develop a coating repair system with excellent oxidation protection performance. In this study, a Mo-modified Si-SiC coating was prepared by laser-inducing to repair the damaged SiC coated C/C composites. Thermal shock test between room temperature and 1773 K was conducted to study the interface bonding and 1773 K cyclic oxidation test was performed to examine the repair effect. With 10 wt% Mo-modification by laser-inducing, MoSi 2 precipitated at the interfaces while the interface bonding was not weaken. The decreased free Si, densified structure of coating and enhanced self-healing ability, which were obtained by modifying, contributed to reduce the mass loss after oxidation by ∼ 70% compared with the damaged sample without repairing. [ABSTRACT FROM AUTHOR]

• Homogeneous and dense Ta x Hf 1−x C solid solution were prepared using arc melting. • Ta 0.75 Hf 0.25 C leads to excellent comprehensive mechanical properties. • The electronic structures of Ta x Hf 1−x C were analyzed by the first-principles. • Relation between mechanical properties and chemical bonds were summarized. Ta x Hf 1−x C can withstand extreme environments, but the challenges in their densification prevent them from being used for many applications. In this paper, a method to prepare dense homogeneous Ta x Hf 1−x C solid solutions with a cubic structure is prosed. Moreover, mechanical properties of Ta x Hf 1−x C are characterized, including the elastic modulus and Poisson ratio. The hardness and Debye temperature are estimated by using empirical equation. The properties related to the electronic structures of Ta x Hf 1−x C (x = 0, 0.25, 0.5, 0.75, 1), including the density of states and Mulliken populations, are systematically calculated by using the first-principles method. From the calculation, we found that all Ta x Hf 1−x C are thermodynamically stable at room temperature. Moreover, Ta 0.5 Hf 0.5 C has a higher Young's modulus and shear modulus comparing to Ta 0.75 Hf 0.25 C and Ta 0.25 Hf 0.75 C. Ta 0.75 Hf 0.25 C possesses the highest bulk modulus, suggesting that it has greater comprehensive mechanical properties than the others. In addition, the compositions of their chemical bonds are discussed according to their density of states, population analysis and Debye temperature. We found that the number of valence electrons of transition metals significantly affects their mechanical properties. Finally, the relation between the mechanical properties of Ta x Hf 1−x C (x = 0, 0.25, 0.5, 0.75, 1) and the chemical bonds are summarized. [ABSTRACT FROM AUTHOR]

This study aimed to explore the effect of cyclosporine (CsA) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in systemic lupus erythematosus (SLE) patients to provide a valuable reference for clinical treatment strategies in the context of the long-term risk of SARS-CoV-2 infection. SLE patients who visited the Rheumatology Outpatient Department of Fujian Medical University Union Hospital between 1 May and 31 October 2022 were included. Data on SARS-CoV-2 infection in patients between 1 November 2022 and 31 July 2023 were obtained by telephone follow-up. Patients were divided into two groups according to whether CsA was used during the observation period: the glucocorticoid or hydroxychloroquine group and the CsA group. To assess the robustness of the results, Data sets 1 and 2 were established to be analyzed independently. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for symptomatic coronavirus disease (COVID-19). A total of 184 patients were included, among whom 129 were definite symptomatic COVID-19 patients; 29 were presumptive symptomatic COVID-19 patients; and 4 had signs and symptoms of COVID-19, but tested negative for SARS-CoV-2 in a virological test. According to the multivariable-adjusted models, CsA was associated with lower odds of symptomatic COVID-19 ( P = 0.042, OR = 0.316, 95% CI: 0.104-0.959 in Data set 1 and P = 0.021, OR = 0.257, 95% CI: 0.081-0.812 in Data set 2). CsA is associated with lower odds of contracting symptomatic COVID-19. The use of CsA may be considered an appropriate therapeutic option for disease management in patients with rheumatic diseases who have severe disease activity and persistent SARS-CoV-2 infection., Importance: Our study indicated that cyclosporine may reduce the risk of symptomatic COVID-19 in systemic lupus erythematosus patients in spite of its immunosuppressive effects. This study provides a reference for clinical treatment strategies for AIIRD patients in the context of the long-term risk of SARS-CoV-2 infection., Competing Interests: The authors declare no conflict of interest.

Background: Systemic lupus erythematosus-associated immune thrombocytopenia (SLE-ITP) is characterized by relapse. The risk factors of relapse and appropriate maintenance therapy strategy deserve further exploration., Objectives: To determine the risk factors for relapse and appropriate maintenance therapy in significant SLE-ITP patients (a platelet count ⩽30 × 10 9 /l) after the first complete response., Design: Retrospective cohort study using the medical records of 105 patients diagnosed as significant SLE-ITP in Fujian Medical University Union Hospital during December 2012 to March 2021. Patients were followed through a call for observations in January 2022., Methods: Data including demographics, initial clinical feature, induction and maintenance therapy, and outcome at the end of follow-up were analyzed. Risk factors for significant relapse were analyzed using multivariate logistic regression models. The cumulative hazard of significant relapse and the duration of response were estimated, and the differences in outcome between groups were compared using the Cox regression analysis., Results: A total of 65 significant SLE-ITP patients were eligible for the final analysis. Median [interquartile range (IQR)] follow-up duration and median [IQR] duration of response were 62.2 [41.0-79.6] months and 43.4 [20.3-68.7] months, respectively. After the first complete response, 19/65 (29.2%) had a significant relapse. Compared with sustained clinical remission (SCR) + sustained response (SR) group, significant relapse group had a higher proportion of discontinued patients (47.4% versus 8.7%, p  = 0.001). Among the 13 discontinued patients, the duration of maintenance therapy of the patients in significant relapse group was significantly shorter than that of the patients in SCR + SR group (months, median [IQR], 43.1 [32.0-62.4] versus 12.0 [5.1-22.0], p  = 0.009). Multivariate logistic regression analysis showed that drug withdrawal was an independent risk factor for significant relapse [odds ratio (OR) = 10.4, confidence interval (CI) 95% 2.2-47.8, p  = 0.003]. There was no significant difference between glucocorticoids (GCs) + hydroxychloroquine (HCQ) group and GCs + HCQ + immunosuppressive agents (ISAs) group in significant relapse rate (26.7% versus 22.2%, p  > 0.05). The two SR curves of GCs + HCQ and GCs + HCQ+ ISA group basically coincided by the Cox regression analysis, demonstrating comparable long-term outcomes ( p  > 0.05)., Conclusion: Drug withdrawal, especially abrupt withdrawal with insufficient duration of maintenance therapy, is an independent risk factor for significant relapse of SLE-ITP. HCQ combined with GCs is expected to be the first choice of the maintenance therapy for SLE-ITP patients., Competing Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s), 2023.)

Progress has been made in COVID-19 vaccine development, with encouraging safety and efficacy data. The purpose of this study was to investigate the immunogenicity of inactivated COVID-19 vaccine in patients with autoimmune inflammatory rheumatic diseases (AIIRD). Patients with AIIRD (n = 101) were included in this study. All patients received 2 doses of inactivated COVID-19 vaccine. Serum anti-S1/RBD protein IgG was detected 2-16 weeks after the second vaccination. Seropositivity was defined as IgG ≥ 1.00 bound antibody unit S/CO. Immunogenicity of inactivated COVID-19 vaccine was assessed by seropositivity rate and the levels of serum IgG antibody against anti-S1/RBD protein, compared with the general population (n = 46). There was no difference by statistical significance in the seropositivity rate between patients with AIIRD (82.2%) and SLE (86.1%) and the control group (93.5%), p > 0.05. The level of anti-S1/RBD protein IgG antibodies in patients with AIIRD (median [IQR], 8.8 [2.2-17.3]) and SLE (median [IQR], 9.6 [2.4-20.4]) was comparable to that in the control group (median [IQR], 7.2 [3.1-14.2]), p > 0.05. Patients treated with glucocorticoids(GCs) (median dose, [IQR]: 2.5 mg/day [IQR 2.5-5.0]) or hydroxychloroquine(HCQ) or GCs + HCQ without other immunomodulatory medications, had an appropriate immunogenic response(88.1%) with high levels of anti-S1/RBD protein IgG(median [IQR], 12.1 [6.5-20.4]). Neither of patients treated with rituximab had positive serum antibodies, which was statistically significant, compared with the control group (p < 0.01). Compared with the control group, methotrexate(MTX) and iguratimod(IGU) was significantly reduced the level of anti-S1/RBD protein IgG antibodies. Inactivated COVID-19 vaccine had appropriate immunogenicity in patients with AIIRD. Immunogenicity of inactivated COVID-19 vaccine was severely impaired by rituximab, and also suppressed by MTX and IGU, while low doses of GC and HCQ had negligible effect., (© 2022. The Author(s).)

Functional modification and structural design of carbon electrode materials are considered as a cost-effective method to improve their electrochemical performance. In this study, a solvothermal method is applied to realize self-assembly of the metal-organic framework. After simple carbonization and acid treatment, carbon nanosheets with 2D adjustable defective sub-units are successfully prepared for the first time. It is found that carbonization temperature has a significant effect on the carbon skeleton structure. The optimal nanostructures with large specific surface area and appropriate pore size distribution make self-assembled carbon nanosheets having excellent Li/Na-ion storage properties. In addition, the adjustable carbon skeleton structure can effectively avoid irreversible damage when charge-discharge cycles. For Li-ion batteries, a specific capacity of 825 mAh g -1 is achieved after 100 cycles at 100 mA g -1 , while for Na-ion batteries a specific capacity of 193 mAh g -1 is observed after 100 cycles at 100 mA g -1 . Moreover, for Na-ion batteries, even at a high rate of 1000 mA g -1 the material delivers a specific capacity of 109.5 mAh g -1 after 3500 cycles.

Lithium-sulfur batteries are regarded as a promising energy storage system. However, they are plagued by rapid capacity decay, low coulombic efficiency, a severe shuttle effect and low sulfur loading in cathodes. To address these problems, effective carriers are highly demanded to encapsulate sulfur in order to extend the cycle life. Herein, we introduced a doped-PEDOT:PSS-coated MIL-101/S multi-core-shell structured composite. The unique structure of MIL-101, large specific area and conductive shell ensure high dispersion of sulfur in the composite and minimize the loss of polysulfides to the electrolyte. The doped-PEDOT:PSS-coated sulfur electrodes exhibited an increase in initial capacity and an improvement in rate characteristics. After 192 cycles at the current density of 0.1C, a doped-PEDOT:PSS-coated MIL-101/S electrode maintained a capacity of 606.62 mA h g -1 , while the MIL-101/S@PEDOT:PSS electrode delivered a capacity of 456.69 mA h g -1 . The EIS measurement revealed that the surface modification with the conducting polymer provided a lower resistance to the sulfur electrode, which resulted in better electrochemical behaviors in Li-S battery applications. Test results indicate that the MIL-101/S@doped-PEDOT:PSS is a promising host material for the sulfur cathode in the lithium-sulfur battery applications., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this article., (This journal is © The Royal Society of Chemistry.)

3D binder-free CuO nanosheets wrapped nanofilms has been in situ synthesized on Cu substrate by a simple and facile procedure, with an aim of fabricating high-performance glucose sensor. The complex morphology that the nanosheet grown on Cu subtract evolved into nanofilms and eventually converged to nanowires, is benefit for the mass transport and electro-catalysis. Compared the ECSA of the CuO modified electrode to that of the bare Cu electrode, the effective surface area during the electro-catalysis of the CuO/Cu electrode is much larger. The glucose sensor based on CuO products exhibited high sensitivity (4201μAcm -2 mM -1 ), low detection limit (0.5μmol/L) and quick response time (0.7s). And the stability and selectivity is also fantastic. According to the serum sample analysis, it transpires that the CuO/Cu sensor displayed excellent recovery compared to the concentration values measured by medial method. So this material shows great potential applications in glucose sensors., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To investigate the effect of culture supernatant form mesenchymal stem cells (MSCs) on the proliferation of rat fibroblast-like synovial cell line RSC-364 and the expression of COX-2, MMP-2., Methods: After isolation and identification of MSCs, the effect of MSCs supernatant liquid (MSCs-SL) on the proliferation of RSC-364 and the expression of COX-2, MMP-2 were detected by MTT assay and RT-PCR., Results: MSCs-SL enhanced the proliferation of synoviocyte and elevated the expression of COX-2 and MMP-2 in synoviocytes (P < 0.05)., Conclusion: MSCs may influence the proliferation of synoviocytes by secreting soluble cytokines and altered the expression level of some enzymes in synoviocytes.

Low molecular mass polypeptides 2 (LMP2) and Multicatalytic endopeptidase complex subunit (MECL-1) are two of three catalytic beta-type subunits of the 20s proteasome and upon interferon gamma-induction. LMP2 is critical for the production of major histocompatibility complex (MHC) class I ligand and T-lymphocytes. The LMP2 gene is located in the MHC region, but MECL-1 is located outside the MHC region. They are involved in the antigen presentation and are important candidate genes for an initial exploration of relationships between the antigen processing genes and disease resistance. In this report, the porcine LMP2 and MECL-1 cDNA were cloned and A 5099 bp LMP2 genomic DNA structure was identified, then two single nucleotide polymorphisms were detected in the exon2 and exon5 of LMP2 gene in 367 individuals. The LMP2 and MECL-1 genes putative protein included 219,274 amino acids, respectively. Alignment and phylogenetic of predicted porcine LMP2 and MECL-1 amino acid sequence with their homologies were analyzed. Tissues expression of LMP2 and MECL-1 mRNA were observed by real time quantitative PCR (Q-PCR) method, the results revealed MECL-1 expressed widely in all tissues, but LMP2 was not detected in muscle. The porcine MECL-1 gene was mapped to chromosome 6, closely linked to microsatellite SW1108 (LOD = 4.09, 84cR) by radiation hybrid panel.

Objective: To detect the mutations of EXT2 gene in hereditary multiple exostoses (HME) families and to investigate the sensitivity of denaturant gradient gel electrophoresis (DGGE) in screening the mutations in EXT2 gene., Methods: Five HME families and 3 sporadic patients were screened for the mutation detection in all exons of EXT2 gene covering the coding sequence and the flanking intronic sequence by DGGE, and DNA sequencing was performed for products with abnormal conformation., Results: Among these HME patients, we found 2 disease-causing mutations: A313T (nonsense mutation) and 319 insGT (frameshift mutation)., Conclusion: Two mutations of EXT2 gene are identified in the sample. DGGE can be an ideal choice for gene diagnoses of HME.

Aim: To investigate the anti-tumor immune response of lymphocytes elicited by HepG2 cells modified with CD80-IgG1 Fc fragment fusion protein (CD80-Fc)., Methods: HepG2 cells were modified with CD80-Fc, then the expression of CD80 on the cell surface was analyzed by flow cytometry (FCM). After mixed lymphocyte-tumour cell reaction (MLTR) of the modified HepG2 cells and peripheral lymphocytes of healthy volunteers, the proliferation and cytotoxicity of the lymphocytes were tested by MTT colorimetry and LDH release assay,respectively., Results: CD80-Fc could be efficiently bound on HepG2 cells. HepG2 cells modified with CD80-Fc fusion protein dramatically elicited proliferation and cytotoxicity of normal lymphocytes., Conclusion: CD80 may play an important role in anti-tumour immune response. HepG2 cells modified with CD80-Fc fusion protein can elicited potent anti-tumor immune response. This fusion protein provides a convenient means for further potential use in immunotherapy of tumor.

The polyamidoamine dendrimers, PAMAM-CMAC, was synthesized by decorating PAMAM dendrimer with coumarin-3-methyl acyl chlorine on the periphery. The structures were characterized by FTIR and H-NMR spectra. The fluorescence analysis indicated the PAMAM-CMAC exhibits strong fluorescence emission. The fluorescence intensity of PAMAM-CMAC is much higher than that of PAMAM dendrimer. The fluorescence intensity of PAMAM-CMAC was affected by pH, concentration and solvent. At a considerably big pH value range, the fluorescence emission of PAMAM-CMAC is comparatively stable. Meanwhile, the fluorescence emission of PAMAM-CMAC shifts to longer wavelength with the increase in solvent polarity.

Aim: To construct an eukaryotic expression vector of CD80-IgG1 Fc, and to express the fusion protein in CHO cells., Methods: The gene encoding the CD80-IgG1 Fc fusion protein were constructed in eukaryotic expression vector pcDNA3.1(+) by means of T-A cloning and subcloning techniques, then was transfected into CHO cells for stable expression. The expression of the fusion protein was detected by Western blot and ELISA., Results: DNA sequencing and restriction endonuclease digestion analysis indicated that the eukaryotic expression vector CD80-IgG1 Fc/pcDNA3.1(+) was successfully constructed. After the recombinant plasmid was transfected into CHO cells, the stable expression of the fusion protein was demonstrated by Western blot and ELISA., Conclusion: The eukaryotic expression vector of CD80-IgG1 Fc/pcDNA3.1(+) was successfully constructed and stably expressed in CHO cells, providing basis for anti-tumor study.

Objective: To study the method for modifying titanium surface with calcium and phosphorus ions using micro-arc oxidation technique and observe osteoblast attachment to the modified surface., Methods: TA(2) titanium discs were treated with micro-arc oxidation in electrolyte solution containing Ca(2+) and PO(4)(3-). The influence of Ca(2+) and PO(4)(3-) concentrations in the solution and the electrical parameters of the micro-arc oxidization on the content of calcium and phosphorus ions incorporated into the surface of titanium was investigated using energy-dispersive X-ray (EDX) analysis. Scanning electron microscopy was employed for morphological observation of the ceramic coating on the metal surface. The binding strength of ceramic coating with titanium was tested by shear bonding experiment. MC-3T3-E1 osteoblast-like cells were then cultured on the treated surface of titanium discs to investigate the influence of the ceramic coating on osteoblast attachment., Results: Micro-arc oxidation treatment produced a layer of porous TiO(2) coating on the surface of titanium discs, with the average pore size of 2 to 10 mum. EDX analysis revealed that the ceramic coating contained Ca and P elements, whose content had close correlation with Ca(2+) and PO(4)(3-) concentrations in the electrolyte solution and voltage, duty cycle and frequency of micro-arc oxidation. The average bonding strength of the ceramic coating with titanium was 22+/-3 MPa, and TiO(2) coating promoted attachment and spread of osteoblast-like cells on the metal surface as demonstrated by cell culture., Conclusions: Porous TiO(2) coating can be constructed on the surface of titanium using micro-arc oxidation, and Ca(2+) and PO(4)(3-) incorporated into the coating can improve the biocompatibility of titanium. The content of Ca(2+) and PO(4)(3-) in the coating can be modulated by adjusting the concentrations of Ca(2+) and PO(4)(3-) in the electrolyte solution and the electrical parameters of the micro-arc oxidation.

Aim: To investigate the changes of CD40 expression and proliferation pattern of EB virus-transformed B lymphocytes that had been transfected by antisense CD40 RNA., Methods: Eukaryotic expression vector pcDNA3/CD40 of human CD40antisense RNA was constructed by means of T-A cloning and subcloning, and then was transfected into EB virus-transformed B lymphocytes. Changes of CD40 expression on the B cells and their proliferation were tested by flow cytometry and MTT colorimetry assay, respectively., Results: CD40 expression and proliferation of the B cells transfected with antisense CD40 RNA were significantly lower than those of the cells transfected with pcDNA3 alone (P < 0. 01)., Conclusion: Antisense CD40 RNA may be served as an effective means of regulating immune function, and the CD40 gene itself also play an important role in cell proliferation.