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1.
Biomed Mater ; 19(4)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38697199

RESUMO

Porous tantalum scaffolds offer a high degree of biocompatibility and have a low friction coefficient. In addition, their biomimetic porous structure and mechanical properties, which closely resemble human bone tissue, make them a popular area of research in the field of bone defect repair. With the rapid advancement of additive manufacturing, 3D-printed porous tantalum scaffolds have increasingly emerged in recent years, offering exceptional design flexibility, as well as facilitating the fabrication of intricate geometries and complex pore structures that similar to human anatomy. This review provides a comprehensive description of the techniques, procedures, and specific parameters involved in the 3D printing of porous tantalum scaffolds. Concurrently, the review provides a summary of the mechanical properties, osteogenesis and antibacterial properties of porous tantalum scaffolds. The use of surface modification techniques and the drug carriers can enhance the characteristics of porous tantalum scaffolds. Accordingly, the review discusses the application of these porous tantalum materials in clinical settings. Multiple studies have demonstrated that 3D-printed porous tantalum scaffolds exhibit exceptional corrosion resistance, biocompatibility, and osteogenic properties. As a result, they are considered highly suitable biomaterials for repairing bone defects. Despite the rapid development of 3D-printed porous tantalum scaffolds, they still encounter challenges and issues when used as bone defect implants in clinical applications. Ultimately, a concise overview of the primary challenges faced by 3D-printed porous tantalum scaffolds is offered, and corresponding insights to promote further exploration and advancement in this domain are presented.


Assuntos
Materiais Biocompatíveis , Substitutos Ósseos , Osso e Ossos , Osteogênese , Impressão Tridimensional , Tantálio , Engenharia Tecidual , Alicerces Teciduais , Tantálio/química , Alicerces Teciduais/química , Porosidade , Humanos , Materiais Biocompatíveis/química , Engenharia Tecidual/métodos , Animais , Substitutos Ósseos/química , Teste de Materiais , Regeneração Óssea
2.
Sci Adv ; 10(16): eadl2063, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640232

RESUMO

All-perovskite tandem solar cells (TSCs) have exhibited higher efficiencies than single-junction perovskite solar cells (PSCs) but still suffer from the unsatisfactory performance of low-bandgap (LBG) tin-lead (Sn-Pb) subcells. The inherent properties of PEDOT:PSS are crucial to high-performance Sn-Pb perovskite films and devices; however, the underlying mechanism has not been fully explored and revealed. Here, we report a facile oxalic acid treatment of PEDOT:PSS (OA-PEDOT:PSS) to precisely regulate its work function and surface morphology. OA-PEDOT:PSS shows a larger work function and an ordered reorientation and fiber-shaped film morphology with efficient hole transport pathways, leading to the formation of more ideal hole-selective contact with Sn-Pb perovskite for suppressing interfacial nonradiative recombination losses. Moreover, OA-PEDOT:PSS induces (100) preferred orientation growth of perovskite for higher-quality Sn-Pb films. Last, the OA-PEDOT:PSS-tailored LBG PSC yields an impressive efficiency of up to 22.56% (certified 21.88%), enabling 27.81% efficient all-perovskite TSC with enhanced operational stability.

3.
Scars Burn Heal ; 10: 20595131241234715, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505821

RESUMO

Introduction: Transcutaneous laser-assisted drug delivery (LADD) is recognized as a developing therapy for skin disorders. Method: Current literature was reviewed to summarize current applications for LADD. Discussion: 12 clinical applications for this therapy are currently reported. Conclusion: LADD has potential for wide application in skin disorder treatment. Lay Summary: Laser assisted drug delivery improves drug bioavailability for treatment of skin disorders. This technique is being assessed clinically in disorders ranging from skin cancers to alopecia.

4.
World J Stem Cells ; 16(2): 191-206, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38455098

RESUMO

BACKGROUND: Knee osteoarthritis (KOA) is a common orthopedic condition with an uncertain etiology, possibly involving genetics and biomechanics. Factors like changes in chondrocyte microenvironment, oxidative stress, inflammation, and immune responses affect KOA development. Early-stage treatment options primarily target symptom relief. Mesenchymal stem cells (MSCs) show promise for treatment, despite challenges. Recent research highlights microRNAs (miRNAs) within MSC-released extracellular vesicles that can potentially promote cartilage regeneration and hinder KOA progression. This suggests exosomes (Exos) as a promising avenue for future treatment. While these findings emphasize the need for effective KOA progression management, further safety and efficacy validation for Exos is essential. AIM: To explore miR-29a's role in KOA, we'll create miR-29a-loaded vesicles, testing for early treatment in rat models. METHODS: Extraction of bone marrow MSC-derived extracellular vesicles, preparation of engineered vesicles loaded with miR-29a using ultrasonication, and identification using quantitative reverse transcription polymerase chain reaction; after establishing a rat model of KOA, rats were randomly divided into three groups: Blank control group injected with saline, normal extracellular vesicle group injected with normal extracellular vesicle suspension, and engineered extracellular vesicle group injected with engineered extracellular vesicle suspension. The three groups were subjected to general behavioral observation analysis, imaging evaluation, gross histological observation evaluation, histological detection, and immunohistochemical detection to compare and evaluate the progress of various forms of arthritis. RESULTS: General behavioral observation results showed that the extracellular vesicle group and engineered extracellular vesicle group had better performance in all four indicators of pain, gait, joint mobility, and swelling compared to the blank control group. Additionally, the engineered extracellular vesicle group had better pain relief at 4 wk and better knee joint mobility at 8 wk compared to the normal extracellular vesicle group. Imaging examination results showed that the blank control group had the fastest progression of arthritis, the normal extracellular vesicle group had a relatively slower progression, and the engineered extracellular vesicle group had the slowest progression. Gross histological observation results showed that the blank control group had the most obvious signs of arthritis, the normal extracellular vesicle group showed signs of arthritis, and the engineered extracellular vesicle group showed no significant signs of arthritis. Using the Pelletier gross score evaluation, the engineered extracellular vesicle group had the slowest progression of arthritis. Results from two types of staining showed that the articular cartilage of rats in the normal extracellular vesicle and engineered extracellular vesicle groups was significantly better than that of the blank control group, and the engineered extracellular vesicle group had the best cartilage cell and joint surface condition. Immunohistochemical detection of type II collagen and proteoglycan showed that the extracellular matrix of cartilage cells in the normal extracellular vesicle and engineered extracellular vesicle groups was better than that of the blank control group. Compared to the normal extracellular vesicle group, the engineered extracellular vesicle group had a better regulatory effect on the extracellular matrix of cartilage cells. CONCLUSION: Engineered Exos loaded with miR-29a can exert anti-inflammatory effects and maintain extracellular matrix stability, thereby protecting articular cartilage, and slowing the progression of KOA.

5.
ACS Appl Mater Interfaces ; 16(9): 11715-11721, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38382471

RESUMO

Inverted perovskite light-emitting diodes (PeLEDs) based on quantum dots (QDs) are some of the most promising candidates for next-generation lighting and display applications. Due to the strong fluorescence quenching caused by zinc oxide, high performance in such inverted devices remains challenging. Here, we report an efficient inverted green CsPbBr3 QDs LED using an emitting buffer layer. Ultrathin CsPbBr3 QD emitters act as the buffer layer to reduce the interface luminescence quenching reaction at the ZnO/upper emitting layer interface, increasing the probability of exciton recombination within the emissive layer and regulating the charge transport, leading to effective carrier recombination. The resulting device exhibits an external quantum efficiency of 13.1%, enhanced by about 4.7 times compared with that without a buffer layer device. This work provides a path to fabricating high-performance inverted PeLEDs.

6.
Science ; 383(6685): 829, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386764

RESUMO

An all-perovskite tandem solar module breaks 24% efficiency.

7.
ACS Biomater Sci Eng ; 10(3): 1435-1447, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38330203

RESUMO

Addressing the repair of large-scale bone defects has become a hot research topic within the field of orthopedics. This study assessed the feasibility and effectiveness of using porous tantalum scaffolds to treat such defects. These scaffolds, manufactured using the selective laser melting (SLM) technology, possessed biomechanical properties compatible with natural bone tissue. To enhance the osteogenesis bioactivity of these porous Ta scaffolds, we applied calcium phosphate (CaP) and magnesium-doped calcium phosphate (Mg-CaP) coatings to the surface of SLM Ta scaffolds through a hydrothermal method. These degradable coatings released calcium and magnesium ions, demonstrating osteogenic bioactivity. Experimental results indicated that the Mg-CaP group exhibited biocompatibility comparable to that of the Ta group in vivo and in vitro. In terms of osteogenesis, both the CaP group and the Mg-CaP group showed improved outcomes compared to the control group, with the Mg-CaP group demonstrating superior performance. Therefore, both CaP and magnesium-CaP coatings can significantly enhance the osseointegration of three-dimensional-printed porous Ta, thereby increasing the surface bioactivity. Overall, the present study introduces an innovative approach for the biofunctionalization of SLM porous Ta, aiming to enhance its suitability as a bone implant material.


Assuntos
Magnésio , Tantálio , Porosidade , Magnésio/farmacologia , Titânio , Fosfatos de Cálcio/farmacologia , Lasers
8.
Adv Mater ; 36(3): e2308240, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37967309

RESUMO

Low-bandgap (LBG, Eg  ≈1.25 eV) tin-lead (Sn-Pb) perovskite solar cells (PSCs) play critical roles in constructing efficient all-perovskite tandem solar cells (TSCs) that can surpass the efficiency limit of single-junction solar cells. However, the traditional poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hole transport layer (HTL) in LBG PSCs usually restricts device efficiency and stability. Here, a strategy of employing 2-aminoethanesulfonic acid (i.e., taurine) as the interface bridge to fabricate efficient HTL-free LBG PSCs with improved optoelectronic properties of the perovskite absorbers at the buried contacts is reported. Taurine-modified ITO substrate has lower optical losses, better energy level alignment, and higher charge transfer capability than PEDOT:PSS HTL, leading to significantly improved open-circuit voltage (VOC ) and short-circuit current density of corresponding devices. The best-performing LBG PSC with a power conversion efficiency (PCE) of 22.50% and an impressive VOC of 0.911 V is realized, enabling all-perovskite TSCs with an efficiency of 26.03%. The taurine-based HTL-free TSCs have highly increased stability, retaining more than 90% and 80% of their initial PCEs after constant operation under 1-sun illumination for 600 h and under 55 °C thermal stress for 950 h, respectively. This work provides a facile strategy for fabricating efficient and stable perovskite devices with a simplified HTL-free architecture.

9.
Photodiagnosis Photodyn Ther ; 45: 103903, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37989473

RESUMO

BACKGROUND: Keloid, a prevalent pathological skin lesion, presents significant challenges in terms of treatment efficacy. Photodynamic therapy (PDT), an increasingly popular adjuvant treatment, has shown significant potential in the management of various disorders, including cancer. However, the therapeutic potential of indocyanine green-mediated photodynamic therapy (ICG-PDT) for keloids has not yet been demonstrated. METHODS: In this study, we divided the experimental groups into control group, Photothermal Therapy group, Photodynamic Therapy group, and Combined Therapy group. The in vitro investigation aimed to optimize the clinical application of PDT for keloid treatment by elucidating its underlying mechanism. Subsequently, on this basis, we endeavored to manage a clinical case of keloid by employing surgical intervention in conjunction with modified ICG-PDT. RESULTS: Our investigation revealed an unexpected outcome that ICG-PDT maximally inhibited the cellular activity and migration of keloid fibroblasts only when photodynamic mechanism took effect. Additionally, the induction of autophagy and apoptosis, as well as the inhibition of collagen synthesis, were particularly evident in this experimental group. Furthermore, the above therapeutic effect could be achieved at remarkably low drug concentrations. Building upon the aforementioned experimental findings, we successfully optimized the treatment modality for the latest case and obtained a more favorable treatment outcome. CONCLUSIONS: This study investigated the mechanism of ICG-PDT treatment and optimized the in vivo treatment regimen, demonstrating the significant therapeutic potential of ICG-PDT treatment in clinical keloid treatment.


Assuntos
Queloide , Fotoquimioterapia , Humanos , Adjuvantes Imunológicos , Verde de Indocianina/farmacologia , Verde de Indocianina/uso terapêutico , Queloide/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico
10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(11): 1423-1430, 2023 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-37987055

RESUMO

Objective: To review the research progress in the construction strategy and application of bone/cartilage immunomodulating hydrogels. Methods: The literature related to bone/cartilage immunomodulating hydrogels at home and abroad in recent years was reviewed and summarized from the immune response mechanism of different immune cells, the construction strategy of immunomodulating hydrogels, and their practical applications. Results: According to the immune response mechanism of different immune cells, the biological materials with immunoregulatory effect is designed, which can regulate the immune response of the body and thus promote the regeneration of bone/cartilage tissue. Immunomodulating hydrogels have good biocompatibility, adjustability, and multifunctionality. By regulating the physical and chemical properties of hydrogel and loading factors or cells, the immune system of the body can be purposively regulated, thus forming an immune microenvironment conducive to osteochondral regeneration. Conclusion: Immunomodulating hydrogels can promote osteochondral repair by affecting the immunomodulation process of host organs or cells. It has shown a wide application prospect in the repair of osteochondral defects. However, more data support from basic and clinical experiments is needed for this material to further advance its clinical translation process.


Assuntos
Cartilagem , Hidrogéis , Osso e Ossos , Engenharia Tecidual/métodos
11.
Front Bioeng Biotechnol ; 11: 1219745, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790252

RESUMO

Objective: This study aimed to evaluate the biomechanical effectiveness of 3D-printed integrated acetabular prosthesis (IAP) and modular acetabular prosthesis (MAP) in reconstructing the acetabulum for patients with Crowe III developmental dysplasia of the hip (DDH). The results of this study can provide a theoretical foundation for the treatment of Crowe III DDH in total hip arthroplasty (THA). Methods: Finite element (FE) analysis models were created to reconstruct Crowe III DDH acetabular defects using IAP and MAP. The contact stress and relative micromotion between the acetabular prosthesis and the host bone were analyzed by gradually loading in three increments (210 N, 2100 N, and 4200 N). In addition, five patients with Crowe III DDH who underwent IAP acetabular reconstruction were observed. Results: At the same load, the peak values of IAP contact stress and relative micromotion were lower than those of MAP acetabular reconstruction. Under jogging load, the MAP metal augment's peak stress exceeded porous tantalum yield strength, and the risk of prosthesis fracture was higher. The peak stress in the bone interface in contact with the MAP during walking and jogging was higher than that in the cancellous bone, while that of IAP was higher than that of the cancellous bone only under jogging load, so the risk of MAP cancellous bone failure was greater. Under jogging load, the relative micromotion of the MAP reconstruction acetabular implant was 45.2 µm, which was not conducive to bone growth, while under three different loads, the relative micromotion of the IAP acetabular implant was 1.5-11.2 µm, all <40 µm, which was beneficial to bone growth. Five patients with IAP acetabular reconstruction were followed up for 11.8 ± 3.4 months, and the Harris score of the last follow-up was 85.4 ± 5.5. The imaging results showed good stability of all prostheses with no adverse conditions observed. Conclusion: Compared with acetabular reconstruction with MAP, IAP has a lower risk of loosening and fracture, as well as a better long-term stability. The application of IAP is an ideal acetabular reconstruction method for Crowe III DDH.

12.
Mater Horiz ; 10(10): 4597-4608, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37593768

RESUMO

Zero-field-cooling exchange bias (ZFC EB) has always been a research hotspot for researchers, because it can realize the movement of the magnetization hysteresis loop along the field axis without field cooling, which greatly expands the universality and convenience of the application of the exchange bias effect. Achieving ZFC EB at room temperature is an ongoing challenge. To this end, a design strategy from the sublattice level is proposed, and a wide temperature range ZFC EB up to room temperature with a vertical magnetization shift is observed in the strained kagome antiferromagnet Mn3.1Sn0.9. Magnetic analysis and first-principles calculations reveal that the ZFC EB arises from the strong exchange interaction between the non-coplanar antiferromagnetic Mn kagome sublattice occupying normal Mn sites and the collinear ferromagnetic Mn sublattice occupying Sn sites. This discovery is of great significance for the application of ZFC EB in antiferromagnetic spintronic devices.

13.
Angew Chem Int Ed Engl ; 62(45): e202308093, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37525424

RESUMO

Tin (Sn)-based perovskites as the most promising absorber materials for lead-free perovskite solar cells (PSCs) have achieved the record efficiency of over 14 %. Although suppressing the oxidation of Sn-based perovskites is a frequently concerned topic for Sn-based PSCs, many studies have given vague explanations and the mechanisms are still under debate. This is in principal due to the lack of an in-depth understanding of various and complex intrinsic and extrinsic factors causing the oxidation process. In this context, we critically review the chemical mechanism of facile oxidation of Sn-based perovskites and differentiate its detrimental effects at material- and device-level. More importantly, we classify and introduce the intrinsic factors (raw materials and solvent of perovskite precursors) and extrinsic factors (exposure to neutral oxygen and superoxide) causing the oxidation with their corresponding anti-oxidation improvement methods. The presented comprehensive understanding and prospect of the oxidation provide insightful guidance for suppressing the oxidation in Sn-based PSCs "from the beginning to the end".

14.
Innovation (Camb) ; 4(5): 100493, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37649733
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(3): 589-594, 2023 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-37380401

RESUMO

Znic (Zn) alloys with good cytocompatibility and suitable degradation rate have been a kind of biodegradable metal with great potential for clinical applications. This paper summarizes the biological role of degradable Zn alloy as bone implant materials, discusses the mechanical properties of different Zn alloys and their advantages and disadvantages as bone implant materials, and analyzes the influence of different processing strategies (such as alloying and additive manufacturing) on the mechanical properties of Zn alloys. This paper provides systematic design approaches for biodegradable Zn alloys as bone implant materials in terms of the material selection, product processing, structural topology optimization, and assesses their application prospects with a view to better serve the clinic.


Assuntos
Ortopedia , Zinco , Ligas , Materiais Dentários , Próteses e Implantes
16.
Mol Med Rep ; 28(1)2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37203399

RESUMO

In the field of orthopedics, defects in large bones have proven challenging to resolve. The aim of the present study was to address this problem through the combination of tantalum metal (pTa) with exosomes derived from bone marrow mesenchymal stem cells (BMSCs), which have the potential to enhance regeneration of full thickness femoral bone defects in rats. Cell culture results demonstrated that exosomes improved the proliferation and differentiation of BMSCs. Following establishment of a supracondylar femoral bone defect, exosomes and pTa were implanted into the defect area. Results demonstrated that pTa acts as a core scaffold for cell adhesion and exhibits good biocompatibility. Moreover, micro­CT scan results as well as histological examination demonstrated that pTa had a significant effect on osteogenesis, with the addition of exosomes further promoting bone tissue regeneration and repair. In conclusion, this novel composite scaffold can effectively promote bone regeneration in large bone defect areas, providing a new approach for the treatment of large bone defects.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Ratos , Animais , Tantálio/metabolismo , Tantálio/farmacologia , Porosidade , Exossomos/metabolismo , Osteogênese , Regeneração Óssea , Fêmur , Células-Tronco Mesenquimais/metabolismo , Alicerces Teciduais , Diferenciação Celular , Engenharia Tecidual/métodos
17.
Orthop Surg ; 15(5): 1264-1271, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36896785

RESUMO

OBJECTIVE: The treatment of acetabular defects is one of the most difficult challenges of revision of total hip arthroplasty (RTHA), and tantalum is regarded as a promising bone substitute material. This study aims to investigate the effectiveness of 3D printed acetabular augment used in RTHA for the treatment of acetabular bone defect. METHODS: A retrospective analysis of the clinical data of seven patients who had undergone RTHA was carried out using 3D printed acetabular augment from January 2017 to December 2018. The CT data of the patients were exported to Mimics 21.0 software (Materialise, Leuven, Belgium), and the acetabular bone defect augment were designed, printed and then implanted during operation. The postoperative Harris score, visual analogue scale (VAS) score and prosthesis position were observed to evaluate the clinical outcome. A I-test was used for preoperative and postoperative comparison of the paired-design dataset. RESULTS: A firm attachment of the bone augment to the acetabulum during operation without any complications was found during the follow-up time 2.8-4.3 years. The VAS score of all patients was found 6.9 ± 1.4 before operation and was 0.7 ± 0.7 at the last follow-up (P ≤ 0.001), and the Harris hip scores, were 31.9 ± 10.3 and 73.3 ± 12.8 before operation, and at the last follow-up (P ≤ 0.001), respectively. Moreover, no loosening sign between the bone defect augment and the acetabulum was observed during the entire implantation period. CONCLUSION: 3D printed acetabular augment is effective in reconstructing the acetabulum following an acetabular bone defect revision, which enhances the hip joint function and eventually makes a satisfactory stable prosthetic.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Acetábulo/cirurgia , Tantálio , Estudos Retrospectivos , Reoperação , Impressão Tridimensional , Falha de Prótese , Seguimentos , Resultado do Tratamento
18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(3): 353-359, 2023 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-36940996

RESUMO

Objective: To summarize the characteristics and biomechanical research progress of common acetabular reconstruction techniques in patients with Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip (DDH) undergoing total hip arthroplasty (THA), and provide references for selecting appropriate acetabular reconstruction techniques for clinical treatment of Crowe type Ⅱ and Ⅲ DDH. Methods: The domestic and foreign relevant literature on biomechanics of acetabular reconstruction with Crowe type Ⅱ and Ⅲ DDH was reviewed, and the research progress was summarized. Results: At present, there are many acetabular reconstruction techniques in Crowe type Ⅱ and Ⅲ DDH patients undergoing THA, with their own characteristics due to structural and biomechanical differences. The acetabular roof reconstruction technique enables the acetabular cup prosthesis to obtain satisfactory initial stability, increases the acetabular bone reserve, and provides a bone mass basis for the possible secondary revision. The medial protrusio technique (MPT) reduces the stress in the weight-bearing area of the hip joint and the wear of the prosthesis, and increases the service life of the prosthesis. Small acetabulum cup technique enables shallow small acetabulum to match suitable acetabulum cup to obtain ideal cup coverage, but small acetabulum cup also increases the stress per unit area of acetabulum cup, which is not conducive to the long-term effectiveness. The rotation center up-shifting technique increases the initial stability of the cup. Conclusion: Currently, there is no detailed standard guidance for the selection of acetabular reconstruction in THA with Crowe type Ⅱ and Ⅲ DDH, and the appropriate acetabular reconstruction technique should be selected according to the different types of DDH.


Assuntos
Artroplastia de Quadril , Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Prótese de Quadril , Humanos , Acetábulo/cirurgia , Luxação Congênita de Quadril/cirurgia , Displasia do Desenvolvimento do Quadril/complicações , Displasia do Desenvolvimento do Quadril/cirurgia , Articulação do Quadril/cirurgia , Artroplastia de Quadril/métodos , Resultado do Tratamento , Estudos Retrospectivos
19.
Adv Mater ; 35(26): e2300136, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36971078

RESUMO

High-performance X-ray scintillators with low detection limits and high light yield are of great importance and are a challenge for low-dose X-ray imaging in medical diagnosis and industrial detection. In this work, the synthesis of a new 2D perovskite, Cs2 CdBr2 Cl2 , via hydrothermal reaction is reported. By doping Mn2+ into the perovskite, a yellow emission located at 593 nm is obtained, and the photoluminescence quantum yield (PLQY) of Cs2 CdBr2 Cl2 :5%Mn2+ perovskite reaches the highest value of 98.52%. The near-unity PLQY and negligible self-absorption of Cs2 CdBr2 Cl2 :5%Mn2+ enable excellent X-ray scintillation performance with a high light yield of 64 950 photons MeV-1 and low detection limit of 17.82 nGyair s-1 . Moreover, combining Cs2 CdBr2 Cl2 :5%Mn2+ with poly(dimethylsiloxane) to fabricate a flexible scintillator screen achieves low-dose X-ray imaging with a high resolution of 12.3 line pairs (lp) mm-1 . The results suggest that Cs2 CdBr2 Cl2 :5%Mn2+ is a promising candidate for low-dose and high-resolution X-ray imaging. The study presents a new approach to designing high-performance scintillators through metal-ion doping.

20.
Front Bioeng Biotechnol ; 11: 1143575, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937751

RESUMO

Objective: To select the most appropriate internal fixation method based on the Pauwels angle, in order to provide a new concept for clinical accurate treatment of femoral neck fractures (FNFs). Methods: FNFs models of Pauwels 30 ° ; 40 ° ; 50 ° ; 60 ° were created respectively. For Pauwels ≤ 50 ° , 1, 2 and 3 Cannulated Compression Screws (CCS) and Porous Tantalum Screws (PTS) were used to fix the fracture for the models. For Pauwels 60 ° , 3CCS and Medial Buttress Plate (MBP) combined with 1, 2 and 3CCS were used to fix the fracture. Based on the results of the finite element (FE) analysis, the biomechanical properties of each model were compared by analyzing and evaluating the following four parameters: maximal stress of the bone (MBS), maximal stress of the implants (MIS), maximal displacement of bone (MBD), interfragmentary motion (IFM). Results: At Pauwels 30 ° , the larger parameters were found in 1CCS, which was 94.8 MPa (MBS), 307.7 MPa (MIS), 0.86 mm (MBD) and 0.36 mm (IFM). In 2CCS group, the parameters were 86.1 MPa (MBS), 254.4 MPa (MIS), 0.73 mm (MBD) and 0.27 mm (IFM), which were similar to those of PTS. At Pauwels 40 ° ; 50 ° , with the increase of the number of used CCS, accordingly, the parameters decreased. Particularly, the MIS (Pauwels 50 ° ) of 1CCS was 1,195.3 MPa, but the other were less than the yield range of the materials. At Pauwels 60 ° , the MBS of 3CCS group was 128.6 Mpa, which had the risk of failure. In 2CCS + MBP group, the parameters were 124.2 MPa (MBS), 602.5 MPa (MIS), 0.75 mm (MBD) and 0.48 mm (IFM), The model stability was significantly enhanced after adding MBP. Conclusion: Pauwels type Ⅰ (< 30 ° ) fractures can reduce the number of CCS, and PTS is an appropriate alternative treatment. For Pauwels type Ⅱ fractures ( 30 ° ∼ 50 ° ), the 3CCS fixation method is still recommended. For Pauwels type Ⅲ fractures (> 50 ° ), it is recommended to add MBP to the medial femoral neck and combine with 2CCS to establish a satisfactory fracture healing environment.

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