Bioinspired Hollow Mesoporous Silica Nanoparticles Coating on Titanium Alloy with Hierarchical Structure for Modulating Cellular Functions

3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding cells.To address the challenges,constructing a bioinspired interface that mimics the hierarchical structure of bone tissue can enhance the cellular functions of cells.In this context,Hollow Mesoporous Silica Nanoparticles(HMSNs),renowned for their unique physicochemical properties and superior biocompatibility,offer a promising direction for this research.In this research,the initially synthesized HMSNs were used to construct a“hollow-mesoporous-macroporous”hierarchical bioinspired coating on the pTi surface through the Layer-by-Layer technique.Simultaneously,diverse morphologies of coatings were established by adjusting the deposition strategy of PDDA/HMSNs on the pTi surface(pTi-HMSN-2,pTi-HMSN-4,pTi-HMSN-6).A range of techniques were employed to investigate the physicochemical properties and regulation of cellular biological functions of the diverse HMSN coating strategies.Notably,the pTi-HMSN-4 and pTi-HMSN-6 groups exhibited the uniform coatings,leading to a substantial enhancement in surface roughness and hydrophilicity.Meantime,the coating constructed strategy of pTi-HMSN-4 possessed commendable stability.Based on the aforementioned findings,both pTi-HMSN-4 and pTi-HMSN-6 facilitated the adhesion,spreading,and pseudopodia extension of BMSCs,which led to a notable upsurge in the expression levels of vinculin protein in BMSCs.Comprehensive analysis indicates that the coating,when PDDA/HMSNs are deposited four times,possesses favorable overall performance.The research will provide a solid theoretical basis for the translation of HMSN bioinspired coatings for orthopedic implants.

A Hybrid Level Set Optimization Design Method of Functionally Graded Cellular Structures Considering Connectivity

With the continuous advancement in topology optimization and additive manufacturing(AM)technology,the capability to fabricate functionally graded materials and intricate cellular structures with spatially varying microstructures has grown significantly.However,a critical challenge is encountered in the design of these structures–the absence of robust interface connections between adjacent microstructures,potentially resulting in diminished efficiency or macroscopic failure.A Hybrid Level Set Method(HLSM)is proposed,specifically designed to enhance connectivity among non-uniform microstructures,contributing to the design of functionally graded cellular structures.The HLSM introduces a pioneering algorithm for effectively blending heterogeneous microstructure interfaces.Initially,an interpolation algorithm is presented to construct transition microstructures seamlessly connected on both sides.Subsequently,the algorithm enables the morphing of non-uniform unit cells to seamlessly adapt to interconnected adjacent microstructures.The method,seamlessly integrated into a multi-scale topology optimization framework using the level set method,exhibits its efficacy through numerical examples,showcasing its prowess in optimizing 2D and 3D functionally graded materials(FGM)and multi-scale topology optimization.In essence,the pressing issue of interface connections in complex structure design is not only addressed but also a robust methodology is introduced,substantiated by numerical evidence,advancing optimization capabilities in the realm of functionally graded materials and cellular structures.

Effect of liniment levamisole on cellular immune functions of patients with chronic hepatitis B

AIM: To explore the effects of liniment levamisole on cellular immune functions of patients with chronic hepatitis B. METHODS: The levels of T lymphocyte subsets and mlL-2R in peripheral blood mononuclear cells (PBMCs) were measured by biotin-streptavidin (BSA) technique in patients with chronic hepatitis B before and after the treatment with liniment levamisole. RESULTS: After one course of treatment with liniment levamisole, the levels of CD3+, CD4+, and the ratio of CD4+/CD8+ increased as compared to those before the treatment but the level of CD8+ decreased. The total expression level of mIL-2R in PBMCs increased before and after the treatment with liniment levamisole. CONCLUSION: Liniment levamisole may reinforce cellular immune functions of patients with chronic hepatitis B.

Functionally Graded Cellular Structure Design Using the Subdomain Level Set Method with Local Volume Constraints

Functional graded cellular structure(FGCS)usually shows superiormechanical behaviorwith lowdensity and high stiffness.With the development of additivemanufacturing,functional graded cellular structure gains its popularity in industries.In this paper,a novel approach for designing functionally graded cellular structure is proposed based on a subdomain parameterized level set method(PLSM)under local volume constraints(LVC).In this method,a subdomain level set function is defined,parameterized and updated on each subdomain independently making the proposed approach much faster and more cost-effective.Additionally,the microstructures on arbitrary two adjacent subdomains can be connected perfectly without any additional constraint.Furthermore,the local volume constraint for each subdomain is applied by virtue of the augmented Lagrange multiplier method.Finally,several numerical examples are given to verify the correctness and effectiveness of the proposed approach in designing the functionally graded cellular structure.From the optimized results,it is also found that the number of local volume constraints has little influence on the convergence speed of the developed approach.

Closed-form solution for shock wave propagation in density-graded cellular material under impact

Density-graded cellular materials have tremendous potential in structural applications where impact resistance is required.Cellular materials subjected to high impact loading result in a compaction type deformation,usually modeled using continuum-based shock theory.The resulting governing differential equation of the shock model is nonlinear,and the density gradient further complicates the problem.Earlier studies have employed numerical methods to obtain the solution.In this study,an analytical closed-form solution is proposed to predict the response of density-graded cellular materials subjected to a rigid body impact.Solutions for the velocity of the impinging rigid body mass,energy absorption capacity of the cellular material,and the incident stress are obtained for a single shock propagation.The results obtained are in excellent agreement with the existing numerical solutions found in the literature.The proposed analytical solution can be potentially used for parametric studies and for effectively designing graded structures to mitigate impact.

Dynamic changes of cellular immune function and individualized adjustments of immunosup-pressant for the management of severe infection after liver transplantation

Objective To explore the dynamic changes of the cellular immune function in severe infection after liver transplantation,and to guide the individualized immunology adjustment. Methods 378 cases of liver transplantation were analyzed retrospectively. Seventy - four cases ( infection group) suffered serious infection,including 54 cases cured ( cure group) ,20 cases died (

Research on the safety evacuation near the building exit

The paper presents an improved cellular automaton model according to the feature of evacuation near the outlet. We studied friction and turning factors that affect pedestrian evacuation speed. By using mathematical methods to derive expressions of friction function and turning function. The average pedestrian outflow of the simulation that includes the effect of both the frictional function and the turning function agrees well with experiment result. On the contrary, the simulation results that only include the effect of the frictional function are not corresponding to the experiment results well. Simulation results show that friction and turning can not be ignored. By analyzing the simulation results, it verified that the model can accurately reflect the actual evacuation process and has practical value.

Zwitterionic betaines over HEPES as the new generation biocompatible pH buffers for cell culture

Good’s buffers have been widely applied in cell/organ culture over the past half a century as biocompatible pH stabilizers.However,the emergence of severe adverse effects,such as cellular uptake,lysosomal autophagic activation,and visible light-induced cytotoxicity,raises serious questions over its biocompatibility while underlying mechanism was unclear.Here we report that riboflavin(RF,component of cell culture medium)generates ^(1)O_(2),⋅OH,and O_(2)^(·-)under visible light exposure during regular cell manipulation.These short half-life reactive oxygen species(ROS)react with tertiary amine groups of HEPES,producing 106.6μM of H_(2)O_(2).Orders of magnitude elevated half-life of ROS in the medium caused severe cytotoxicity and systematic disorder of normal cell functions.We have further designed and validated zwitterionic betaines as the new generation biocompatible organic pH buffers,which is able to completely avoid the adverse effects that found on HEPES and derivate Good’s buffers.These findings may also open a new avenue for zwitterionic betaine based materials for biomedical applications.

Pathogenic roles of long noncoding RNAs in melanoma: Implications in diagnosis and therapies

Melanoma is one of the most dangerous types of cutaneous neoplasms,which are pigment-producing cells of neuroectodermal origin found all over the body.A great deal of research is focused on the mechanisms of melanoma to promote better diagnostic and treatment options for melanoma in its advanced stages.The progression of melanoma involves alteration in different levels of gene expression.With the successful implementation of next-generation sequencing technology,an increasing number of long noncoding RNAs(lncRNAs)sequences have been discovered,and a significant number of them have phenotypic effects in both in vitro and in vivo studies,implying that they play an important role in the occurrence and progression of human cancers,particularly melanoma.A number of evidence indicated that lncRNAs are important regulators in tumor cell proliferation,invasion,apoptosis,immune escape,energy metabolism,drug resistance,epigenetic regulation.To better understand the role of lncRNAs in melanoma tumorigenesis,we categorize melanomaassociated lncRNAs according to their cellular functions and associations with gene expression and signaling pathways in this review.Based on the mechanisms of lncRNA,we discuss the possibility of lncRNA-target treatments,and the application of liquid biopsies to detect lncRNAs in melanomadiagnosisandprognosis.