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1.
Opt Express ; 32(8): 14607-14619, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859401

RESUMO

X-ray dual-phase grating interferometry provides quantitative micro-structural information beyond the optical resolution through its tunable correlation length. Ensuring optimal performance of the set-up requires accurate correlation length estimation and precise alignment of the gratings. This paper presents an automated procedure for determining the complete geometrical parameters of the interferometer set-up with a high degree of precision. The algorithm's effectiveness is then evaluated through a series of experimental tests, illustrating its accuracy and robustness.

2.
Langmuir ; 40(1): 927-937, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38134293

RESUMO

High-performance reusable materials from renewable resources are rare and urgently required in bioseparation. Herein, a series of tannic acid-chitosan composite membranes for the enrichment of phosphopeptides were fabricated by the freeze casting method. First, a tannic acid-chitosan composite membrane was acquired via the multiple hydrogen bonds between tannic acid and chitosan, which had a long-range aligned three-dimensional microstructure. Second, a covalent-hydrogen bond hybrid composite was also fabricated, with stable and aligned honeycomb-like microstructures that formed by the synergy of covalence and hydrogen bonding. Besides, a ternary composite membrane was "one-pot" synthesized by the copolymerization of tannic acid, chitosan, and Ti4+ ions, indicating the feasibility of involving metal ions in the composition of the polymer skeleton in place of additional modification steps. The as-prepared chitosan composite membranes exhibited excellent performance in the enrichment of phosphopeptides from ß-casein tryptic digest and human serum. Benefitting from the long-range aligned honeycomb-like structure coordinated by hydrogen bonds and covalent bonds, and a large number of pyrogallol functional groups provided by tannic acid, the covalent-hydrogen bond hybrid membrane showed excellent reusability and could be reused up to 16 times in phosphopeptide enrichment, as far as we know, which is the best reported result to date.


Assuntos
Quitosana , Fosfopeptídeos , Humanos , Fosfopeptídeos/química , Quitosana/química , Titânio/química , Íons
3.
EMBO Rep ; 23(12): e55687, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36281991

RESUMO

Primary cilia (PC) are important signaling hubs, and we here explored their role in colonic pathology. In the colon, PC are mostly present on fibroblasts, and exposure of mice to either chemically induced colitis-associated colon carcinogenesis (CAC) or dextran sodium sulfate (DSS)-induced acute colitis decreases PC numbers. We generated conditional knockout mice with reduced numbers of PC on colonic fibroblasts. These mice show increased susceptibility to CAC, as well as DSS-induced colitis. Secretome and immunohistochemical analyses of DSS-treated mice display an elevated production of the proinflammatory cytokine IL-6 in PC-deficient colons. An inflammatory environment diminishes PC presence in primary fibroblast cultures, which is triggered by IL-6 as identified by RNA-seq analysis together with blocking experiments. These findings suggest an activation loop between IL-6 production and PC loss. An analysis of PC presence on biopsies of patients with ulcerative colitis or colorectal cancer (CRC) reveals decreased numbers of PC on colonic fibroblasts in pathological compared with surrounding normal tissue. Taken together, we provide evidence that a decrease in colonic PC numbers promotes colitis and CRC.


Assuntos
Cílios , Interleucina-6 , Camundongos , Animais , Interleucina-6/genética
4.
Opt Express ; 31(2): 1677-1691, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785198

RESUMO

In this work, we analyze the interference patterns measured in lab-based dual-phase grating interferometry and for the first time explain the spatial dependencies of the measured interference patterns and the large visibility deviations between the theoretical prediction and the experimental results. To achieve this, a simulator based on wave propagation is developed. This work proves that the experimental results can be simulated with high accuracy by including the effective grating thickness profile induced by the cone-beam geometry, the measured detector response function and a non-ideal grating shape. With the comprehensive understanding of dual-phase grating interferometry, this provides the foundations for a more efficient and accurate algorithm to retrieve sample's structure information, and the realistic simulator is a useful tool for optimizing the set-up.

5.
Opt Express ; 31(24): 40450-40468, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041345

RESUMO

The dark-field signal provided by X-ray grating interferometry is an invaluable tool for providing structural information beyond the direct spatial resolution and their variations on a macroscopic scale. However, when using a polychromatic source, the beam-hardening effect in the dark-field signal makes the quantitative sub-resolution structural information inaccessible. Especially, the beam-hardening effect in dual-phase grating interferometry varies with spatial location, inter-grating distance, and diffraction order. In this work, we propose a beam-hardening correction algorithm, taking into account all these factors. The accuracy and robustness of the algorithm are then validated by experimental results. This work contributes a necessary step toward accessing small-angle scattering structural information in dual-phase grating interferometry.

6.
Anal Chem ; 94(12): 5159-5166, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35300494

RESUMO

Enrichment and identification of phosphopeptides in real biological samples are of great significance in many aspects. Herein, Ti4+-immobilized silica hollow nanospheres were tailored via chelating with phosphonic acid groups produced from dealkylation of phosphonate ester functionalized silica hollow nanospheres, which were synthesized through a single micelle templated method with diethylphosphatoethyltriethoxysilane (DPTES) and tetramethoxysilane (TMOS) as silane precursors under neutral conditions. The characterization results of transmission electron microscopy (TEM), nitrogen sorption isotherms, FT-IR, and energy-dispersive X-ray (EDX) spectroscopy confirmed the successful preparation of Ti4+-immobilized silica hollow nanospheres (SHS-Ti; approximately 17 nm particle size), which possessed a 10 nm hollow cavity with 1.6 nm micropores on the thin shell (about 3.5 nm). Attributed to the immobilized Ti4+ and high specific area (396 m2/g), SHS-Ti was applied as a Ti4+-immobilized metal affinity chromatography (Ti-IMAC) material and showed good specificity, a low limit of detection (5 fmol), high selectivity (tryptic digestion mixture of bovine serum albumin/ß-casein, 1000:1 molar ratio), high binding capacity (120 mg/g for pyridoxal 5'-phosphate), and a high binding constant (1.30 × 103 L/mg). Particularly, benefiting from the unique hollow structure with microwindows on the thin shell, a short transport path, and small mass transfer resistance, SHS-Ti exhibited excellent enrichment speed in which both phosphopeptide loading and elution could be completed in 1 min. The 5298 unique phosphopeptides from 1618 unique phosphoproteins were identified after enrichment by SHS-Ti from 100 µg Jurkat cell lysates within three independent replicates. The results showed that SHS-Ti could be utilized as a novel and promising enrichment probe for phosphopeptide characterization in MS-based phosphoproteomics and related fields.


Assuntos
Nanosferas , Fosfopeptídeos , Sítios de Ligação , Cromatografia de Afinidade/métodos , Nanosferas/química , Fosfopeptídeos/análise , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/química
7.
J Sep Sci ; 45(8): 1458-1468, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34559936

RESUMO

Through a "one-pot" strategy, a layer of microporous organic polymer was coated onto the surface of monodisperse amino-functionalized silica microsphere via amino-aldehyde condensation reaction with core-shell structure. The change in chemical structure of material before and after modification was determined by Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Due to existence of a large number of amino and aldehyde groups in microporous organic polymer shell, the water contact angle decreased from 56.8° (silica microspheres) to 34.7° (microporous organic polymer-coated silica microspheres). Based on these properties, microporous organic polymer-coated silica microspheres were employed as the stationary phase for capillary liquid chromatography and successfully offered baseline separation of polar small molecules. Additionally, the material could also be served as the sorbent of hydrophilic interaction chromatography to enrich glycopeptides from human serum digest. A total of 470 unique N-glycopeptides and 342 N-glycosylation sites mapped to 112 N-glycosylated proteins were unambiguously identified from 2 µL of human serum, exhibiting a promising application prospect of microporous organic polymer-coated silica microspheres in the pretreatment of proteomics samples.


Assuntos
Glicopeptídeos , Dióxido de Silício , Cromatografia Líquida , Glicopeptídeos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Polímeros/química , Dióxido de Silício/química
8.
Mikrochim Acta ; 189(11): 405, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-36197509

RESUMO

Enrichment of phosphopeptides before mass spectrometry (MS) analysis is essential due to the limitations of low abundance and poor ionization efficiency in complex biological samples. Immobilized metal affinity chromatography (IMAC), especially titanium ion (Ti4+)-IMAC, has become a popular strategy for enrichment of phosphopeptides due to high selectivity and sensitivity. Conventional Ti4+-immobilized macroporous adsorption resin (MAR) fabricated by monolayer modification can preferentially capture mono-phosphopeptide over multi-phosphopeptides, which takes on more functions in the regulation of cell behaviors of organism. In this paper, a kind of monodisperse MAR microsphere with functional polymer brush (Ti4+-Brush@MAR) was prepared and modified via surface-initiated atom transfer radical polymerization (SI-ATRP). Compared with common Ti4+-MAR without polymer brush, Ti4+-Brush@MAR exhibited high enrichment specificity not only for mono-phosphopeptides but also for multi-phosphopeptides in ß-casein or milk digest samples. As a result, a total of 93 unique phosphopeptides mapped to 18 phosphoproteins were identified from 5 µL milk, and the limit of detection is 10 fmol. It is expected that Ti4+-Brush@MAR would be utilized to enrich both multi-phosphopeptides and mono-phosphopeptides in additional biological or food samples.


Assuntos
Leite , Titânio , Animais , Caseínas/química , Cromatografia de Afinidade/métodos , Leite/química , Fosfopeptídeos/análise , Polímeros , Titânio/química
9.
Mikrochim Acta ; 189(3): 124, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35226167

RESUMO

A kind of core-shell composite microsphere (CM) with nano-on-micro structure was synthesized via grafting amine-modified nanodiamonds onto the surface of monodisperse nonporous polymeric microsphere. In this way, the agglomeration of nanodiamond particles in the solution was avoided. After modification with pyrogallol groups, CM could chelate titanium ions (Ti4+) and thus be utilized as immobilized metal affinity chromatography (IMAC) sorbent to enrich phosphopeptides from biological samples. The resulting Ti4+-CM exhibited high enrichment efficiency and specificity to phosphopeptides. A total of 106 of unique phosphopeptides mapped to 29 phosphoproteins were clearly identified from 5 µL of a milk digest after enrichment. Owing to the strong chelation between Ti4+ and pyrogallol ligands, the Ti4+ is not released from the sorbent after completion of the enrichment process. As a result, the Ti4+-CM sorbent could be reused, and no significant loss of enrichment efficiency occurred even on the fourth run employing a ß-casein digest as the sample. The strategy adopted presents a new way to prepare a high-performance reusable IMAC sorbent.


Assuntos
Nanodiamantes , Fosfopeptídeos , Caseínas/química , Cromatografia de Afinidade/métodos , Microesferas , Fosfopeptídeos/análise
10.
Mikrochim Acta ; 188(10): 348, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34542721

RESUMO

A kind of zwitterionic microsphere was prepared via one-step inverse suspension polymerization employing 3-[N,N-dimethyl-[2-(2-methylpropyl-2-enyloxy) ethyl] ammonium] propane-1-sulfonate (MSA) and N,N-methylene bisacrylamide (BIS) as the precursors. The preparation conditions were carefully investigated and optimized by regulating the content of total monomers, ratio of MSA to BIS, ratio of water to oil, and content of stabilizer. The properties of microspheres were characterized by helium ion microscopy (HIM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), N2 adsorption/desorption measurement, and water contact angle measurement. The particle size of resulting polydisperse microspheres ranged from 15-25 µm, exhibiting high specific surface area of 138 m2 g-1. Owing to great hydrophilicity, the resulting zwitterionic microspheres could be directly used as hydrophilic interaction chromatography (HILIC) sorbent to enrich glycopeptides from biosamples without any chemical modification. A total of 19 N-glycopeptides was enriched from 10 µg of IgG digest. Besides, up to 383 N-glycopeptides and 224 N-glycosylation sites were unambiguously identified from 2 µL of human serum digest by cLC-MS/MS after enrichment with zwitterionic microspheres, indicating their great enrichment performance to N-glycopeptides. The approach of preparing hydrophilic zwitterionic microspheres contains only one synthesis reaction and is suitable for large-scale preparation.


Assuntos
Glicopeptídeos/sangue , Glicopeptídeos/química , Microesferas , Acrilamidas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imunoglobulina G/química , Polimerização , Ácidos Sulfônicos/química
11.
J Org Chem ; 83(21): 12977-12984, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30289259

RESUMO

Multifunction luminogens have emerged as promising candidates in high-performance sensor and imaging systems. Concise approaches to the synthesis of such molecules are urgently required both for fundamental research and technological applications. In this study, a new symmetric ligand of di(2-hydroxyphenyl)phthalazine with multiple binding sites around a phthalazine unit was readily synthesized, which could be converted efficiently into an asymmetric luminogen (OBN-DHPP) through the formation of oxygen-boron-nitrogen bonding. This molecule has a twistable π-extended backbone with a tetracoordinated boron core bearing two bulky phenyl groups, giving it abundant optical properties including a large Stokes shift piezochromism and aggregation-induced emission enhancement. Importantly, the presence of a free phenolic hydroxyl group in the backbone of OBN-DHPP enables the incorporation of various functional moieties into the asymmetric luminogen. As an example, polyethylene glycol (PEG)-modified luminogen (OBN-DHPP-PEG45) was synthesized. In the aqueous medium, OBN-DHPP-PEG45 could self-assemble into spherical nanoparticles with low cytotoxicity and excellent emission performance as well as high solubility. The results of flow cytometry and fluorescence microscopy reveal that these nanoparticles could be internalized successfully by HeLa cells, demonstrating their potential application in bioimaging.

12.
Opt Express ; 25(14): 16603-16617, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28789162

RESUMO

Recently mode-division-multiplexing (MDM) has been widely investigated to enhance fiber optics capacity, in which modes or mode groups in few-mode fiber (FMF) or multi-mode fiber (MMF) are exploited as different spatial channels for data transmission. For short-reach applications, significantly reducing inter-spatial-channel crosstalk to avoid coherent detection and multiple-input-multiple-output (MIMO) equalization is preferred. Currently most studies focus on the design of weakly-coupled FMFs and mode (de)multiplexers. Alternatively, in this work, a wavelength-interleaved (WI) scheme is proposed to mitigate inter-spatial-channel crosstalk by optimizing the design of direct detection (DD) MDM and wavelength-division-multiplexing (WDM) system. In weakly-coupled MDM systems, crosstalk mainly comes from the adjacent spatial channels, and the signal-to-crosstalk beat interference (SCBI) constitutes main crosstalk impairment after square-law detection. The WI scheme interleaves the WDM grids in adjacent spatial channels by half WDM channel spacing and uses an electrical low-pass filtering (ELPF) to remove out-of-band SCBI. The effectiveness of SCBI suppression is theoretically analyzed. The feasibility of WI scheme is experimentally verified by 3-mode 3-wavelength MDM-WDM transmission over 500-m OM3 MMF. Enabled by WI scheme, record 120-km 10G-per-channel MDM-WDM transmission over 2-mode FMF without MIMO equalization is successfully demonstrated. The WI scheme is promising to enhance the performance of short reach or even metro MDM optics.

13.
J Am Chem Soc ; 138(36): 11606-15, 2016 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-27541867

RESUMO

A novel class of dibenzo-fused 1,9-diaza-9a-boraphenalenes featuring zigzag edges with a nitrogen-boron-nitrogen bonding pattern named NBN-dibenzophenalenes (NBN-DBPs) has been synthesized. Alternating nitrogen and boron atoms impart high chemical stability to these zigzag-edged polycyclic aromatic hydrocarbons (PAHs), and this motif even allows for postsynthetic modifications, as demonstrated here through electrophilic bromination and subsequent palladium-catalyzed cross-coupling reactions. Upon oxidation, as a typical example, NBN-DBP 5a was nearly quantitatively converted to σ-dimer 5a-2 through an open-shell intermediate, as indicated by UV-vis-NIR absorption spectroscopy and electron paramagnetic resonance spectroscopy corroborated by spectroscopic calculations, as well as 2D NMR spectra analyses. In situ spectroelectrochemistry was used to confirm the formation process of the dimer radical cation 5a-2(•+). Finally, the developed new synthetic strategy could also be applied to obtain π-extended NBN-dibenzoheptazethrene (NBN-DBHZ), representing an efficient pathway toward NBN-doped zigzag-edged graphene nanoribbons.

14.
Opt Express ; 24(4): 4076-87, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26907058

RESUMO

Elastic optical network (EON) has been proposed recently as a spectrum-efficient optical layer to adapt to rapidly-increasing traffic demands instead of current deployed wavelength-division-multiplexing (WDM) optical network. In contrast with conventional WDM optical cross-connect (OXCs) based on wavelength selective switches (WSSs), the EON OXCs are based on spectrum selective switches (SSSs) which are much more expensive than WSSs, especially for large-scale switching architectures. So the transition cost from WDM OXCs to EON OXCs is a major obstacle to realizing EON. In this paper, we propose and experimentally demonstrate a transition OXC (TOXC) structure based on 2-stage cascading switching architectures, which make full use of available WSSs in current deployed WDM OXCs to reduce number and port count of required SSSs. Moreover, we propose a contention-aware spectrum allocation (CASA) scheme for EON built with the proposed TOXCs. We show by simulation that the TOXCs reduce the network capital expenditure transiting from WDM optical network to EON about 50%, with a minor traffic blocking performance degradation and about 10% accommodated traffic number detriment compared with all-SSS EON OXC architectures.

15.
J Org Chem ; 80(20): 10127-33, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26418754

RESUMO

The 2-fold successive electrophilic borylation on one aromatic central core led to a series of C(2h)-symmetric BN-heteroacenes in excellent yields. For the first time, we introduced trimethylsilyl (TMS) as either leaving group or oriented group for efficiently improving the preparation of BN-embedded polycyclic aromatic hydrocarbons (PAHs). The physical properties of the as-synthesized BN-heteroacenes in either solid state or solution can be finely tuned through the position isomerization or the fused ring numbers of the aromatic central core.

16.
ACS Appl Mater Interfaces ; 16(9): 11275-11288, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38383056

RESUMO

The current research models of breast cancer are usually limited in their capacity to recapitulate the tumor microenvironment in vitro. The lack of an extracellular matrix (ECM) oversimplifies cell-cell or cell-ECM cross-talks. Moreover, the lack of tumor-associated macrophages (TAMs), that can comprise up to 50% of some solid neoplasms, poses a major problem for recognizing various hallmarks of cancer. To address these concerns, a type of direct breast cancer cells (BCCs)-TAMs coculture organoid model was well developed by a sequential culture method in this study. Alginate cryogels were fabricated with appropriate physical and mechanical properties to serve as an alternative ECM. Then, our previous experience was leveraged to polarize TAMs inside of the cryogels for creating an in vitro immune microenvironment. The direct coculture significantly enhanced BCCs organoid growth and cancer aggressive phenotypes, including the stemness, migration, ECM remodeling, and cytokine secretion. Furthermore, transcriptomic analysis and protein-protein interaction networks implied certain pathways (PI3K-Akt pathway, MAPK signaling pathway, etc.) and targets (TNF, PPARG, TLR2, etc.) during breast cancer progression in a TAM-leading immune microenvironment. Future studies to advance treatment strategies for BCC patients may benefit from using this facile model to reveal and target the interactions between cancer signaling and the immune microenvironment.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Macrófagos Associados a Tumor/metabolismo , Técnicas de Cocultura , Biomimética , Criogéis/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Macrófagos/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral
17.
Sci Rep ; 14(1): 384, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172504

RESUMO

The multi-scale characterization of building materials is necessary to understand complex mechanical processes, with the goal of developing new more sustainable materials. To that end, imaging methods are often used in materials science to characterize the microscale. However, these methods compromise the volume of interest to achieve a higher resolution. Dark-field (DF) contrast imaging is being investigated to characterize building materials in length scales smaller than the resolution of the imaging system, allowing a direct comparison of features in the nano-scale range and overcoming the scale limitations of the established characterization methods. This work extends the implementation of a dual-phase X-ray grating interferometer (DP-XGI) for DF imaging in a lab-based setup. The interferometer was developed to operate at two different design energies of 22.0 keV and 40.8 keV and was designed to characterize nanoscale-size features in millimeter-sized material samples. The good performance of the interferometer in the low energy range (LER) is demonstrated by the DF retrieval of natural wood samples. In addition, a high energy range (HER) configuration is proposed, resulting in higher mean visibility and good sensitivity over a wider range of correlation lengths in the nanoscale range. Its potential for the characterization of mineral building materials is illustrated by the DF imaging of a Ketton limestone. Additionally, the capability of the DP-XGI to differentiate features in the nanoscale range is proven with the dark-field of Silica nanoparticles at different correlation lengths of calibrated sizes of 106 nm, 261 nm, and 507 nm.

18.
Mater Today Bio ; 19: 100607, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36960095

RESUMO

Clinical evidence supports a role for the extracellular matrix (ECM) in cancer plasticity across multiple tumor types. The lack of in vitro models that represent the native ECMs is a significant challenge for cancer research and drug discovery. Therefore, a major motivation for developing new tumor models is to create the artificial ECM in vitro. Engineered biomaterials can closely mimic the architectural and mechanical properties of ECM to investigate their specific effects on cancer progression, offering an alternative to animal models for the testing of cancer cell behaviors. In this review, we focused on the biomaterials from different sources applied in the fabrication of the artificial ECM and their biophysical cues to recapitulate key features of tumor niche. Furthermore, we summarized how the distinct biophysical cues guided cell behaviors of cancer plasticity, including morphology, epithelial-to-mesenchymal transition (EMT), enrichment of cancer stem cells (CSCs), proliferation, migration/invasion and drug resistance. We also discuss the future opportunities in using the artificial ECM for applications of tumorigenesis research and precision medicine, as well as provide useful messages of principles for designing suitable biomaterial scaffolds.

19.
STAR Protoc ; 4(4): 102749, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38041821

RESUMO

Establishing a long-term ex vivo observation of the intestinal stem cell (ISC) is crucial to help understand the formation and homeostasis of the intestinal epithelium. Here, we present a protocol for tracking the division of Drosophila pupal ISCs during pupal midgut development. We describe steps for dissecting, mounting, and live imaging the pupal midgut. We then detail procedures for fluorescence quantification of each cell. This protocol can be applied to other fluorescently tagged proteins. For complete details on the use and execution of this protocol, please refer to Wu et al.1.


Assuntos
Drosophila melanogaster , Intestinos , Animais , Pupa , Mucosa Intestinal , Drosophila , Divisão Celular
20.
Materials (Basel) ; 16(8)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37109987

RESUMO

Hip replacement femoral implants are made of substantial materials that all have stiffness considerably higher than that of bone, which can cause significant bone resorption secondary to stress shielding and lead to severe complications. The topology optimization design method based on the uniform distribution of material micro-structure density can form a continuous mechanical transmission route, which can better solve the problem of reducing the stress shielding effect. A multi-scale parallel topology optimization method is proposed in this paper and a topological structure of type B femoral stem is derived. Using the traditional topology optimization method (Solid Isotropic Material with Penalization, SIMP), a topological structure of type A femoral stem is also derived. The sensitivity of the two kinds of femoral stems to the change of load direction is compared with the variation amplitude of the structural flexibility of the femoral stem. Furthermore, the finite element method is used to analyze the stress of type A and type B femoral stem under multiple conditions. Simulation and experimental results show that the average stress of type A and type B femoral stem on the femur are 14.80 MPa, 23.55 MPa, 16.94 MPa and 10.89 MPa, 20.92 MPa, 16.50 MPa, respectively. For type B femoral stem, the average error of strain is -1682µÎµ and the average relative error is 20.3% at the test points on the medial side and the mean error of strain is 1281µÎµ and the mean relative error is 19.5% at the test points on the outside.

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