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1.
J Orthop Surg (Hong Kong) ; 32(1): 10225536231224952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38217531

RESUMO

In the burgeoning domain of orthopedic therapeutic research, Platelet-Rich Plasma (PRP) has firmly established its position, transforming paradigms ranging from tissue regeneration to the management of chondral lesions. This review delves into PRP's recent integrations with cutting-edge interventions such as 3D-printed scaffolds, its role in bone and cartilage defect management, and its enhanced efficacy when combined with molecules like Kartogenin (KGN) for fibrocartilage zone repair. Significant attention is paid to tissue engineering for meniscal interventions, where a combination of KGN, PRP, and bone marrow-derived mesenchymal stem cells are under exploration. Within the sphere of osteochondral regenerative therapy, the synergy of PRP with Bone Marrow Aspirate Concentrate (BMAC) represents a noteworthy leap towards cartilage regeneration. The innovative incorporation of PRP with biomaterials like hydroxyapatite and graphene oxide further underscores its versatility in supporting structural integrity and ensuring sustained growth factor release. However, while PRP's autologous and nontoxic nature makes it an inherently safe option, concerns arising from its preparation methods, particularly with bovine thrombin, necessitate caution. As of 2023, despite the burgeoning promise of PRP in bone healing, the quest for its standardization, optimization, and substantiation through rigorous clinical trials continues. This comprehensive review elucidates the contemporary applications, challenges, and future trajectories of PRP in orthopedics, aiming to spotlight areas primed for further research and exploration.


Assuntos
Procedimentos de Cirurgia Plástica , Plasma Rico em Plaquetas , Humanos , Animais , Bovinos , Cicatrização , Materiais Biocompatíveis , Artrodese , Plasma Rico em Plaquetas/química , Plasma Rico em Plaquetas/metabolismo
2.
World Neurosurg ; 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37343670

RESUMO

OBJECTIVE: To identify the risk factors for developing postoperative pulmonary infection in patients with acute cervical spinal cord injury (CSCI), and to develop a nomogram prediction model. METHODS: Patients with CSCI who were admitted to 3 different medical centers between July 2011 and July 2021 were included in this study. All patients underwent cervical spine surgery. Data for patients admitted to the first 2 centers were included in a training set to establish the nomogram prediction model, and data for patients admitted to the third center were included in a validation set to externally verify the efficacy of the prediction model. For the training set, patients were divided into an infected group and a noninfected group (control group). Independent risk factors for postoperative pulmonary infection in patients with CSCI were identified by univariate and multivariate logistic regression analyses. Additionally, a nomogram prediction model was developed and validated based on the risk factors. RESULTS: A total of 689 patients were enrolled, including 574 for the training set and 115 for the validation set. Of the patients included for the training set, 144 developed pulmonary infection, with an incidence of 25.09%; 40 patients included for the validation set developed pulmonary infection (34.78%). Multivariate logistic regression analysis showed that age, American Spinal Injury Association grade, steroid pulse, high-level injury, smoking, multistage surgery, and operation duration were risk factors for the development of postoperative pulmonary infection in patients with CSCI. The area under the curve of the receiver operating characteristic curve of the model built by the training set was 0.905, and that of the receiver operating characteristic curve of the verification set was 0.917. The decision curve indicated that the model was in the range 1%-100%, and the predicted net benefit value of the model was high. CONCLUSIONS: Age, American Spinal Injury Association grade, steroid pulse, CSCI site, smoking history, number of surgical levels, and surgical duration are correlated with the development of postoperative pulmonary infection in patients with CSCI. The risk prediction model of postoperative pulmonary infection has a good prediction efficiency and accuracy.

3.
ACS Omega ; 8(1): 1567-1576, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643523

RESUMO

Although many strategies have been reported for modified poly(p-phenylene benzobisoxazole) (PBO) fiber surfaces, the absence of approaches with the potential of applications in industries limits the further applications of the fibers in a wide field. Herein, PBO fibers are modified by heat treatment combined with corona discharge treatment, which is a continuous industrialized method. Then, the surface morphology, wettability, orientation, and crystallinity of the PBO fibers are characterized in detail. Systematic experiments demonstrate that the high thermal treatment can improve the orientation and crystallization degree of the fibers, as well as the degradation resistance. In addition, owing to the synergistic mechanism of ozone and high-frequency shock, the corona discharge treatment increases the contents of O and N elements on the surfaces, which improves the superficial properties of the fibers. Based on the modification of PBO fibers, the inter-laminar shear strength between the fiber and the resin for the composite increases to 94.8%, and the tensile strength of the composite increases to 29.2%, compared to those using untreated fibers. In general, the proposed modification strategy not only easily improves the surface properties and the mechanical properties of composites but also can be used with great potential in industrial production.

4.
J Org Chem ; 74(5): 2200-2, 2009 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-19196026

RESUMO

A copper-catalyzed process has been developed for the N-arylation reaction under very mild conditions in the absence of additional ligand. This protocol could not only tolerate an array of thermally sensitive functional groups, but also achieve high chemoselectivity.


Assuntos
Cobre/química , Compostos Heterocíclicos/síntese química , Nitrogênio/química , Catálise , Compostos Heterocíclicos/química , Hidrocarbonetos Halogenados/química , Estrutura Molecular , Estereoisomerismo , Temperatura
5.
J Am Chem Soc ; 129(45): 13879-86, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17941636

RESUMO

Novel supported task-specific ionic liquids have been developed for the first time via the ionic-pair coupling of imidazolium cation of the modified polystyrene support with L-proline. The materials have shown an efficient metal scavenging ability (e.g., CuI, Pd(OAc)2, Pd0, and IrCl3) without the aid of a nonimmobilized ionic liquid, which relies on the highly synergistic effect of the coordination with the nitrogen atom and the COO- group of the L-proline moiety, electrostatic forces, and steric protection. The resulting metal-soaked supported ionic liquids can be used as efficient heterogeneous catalysts. These materials have been investigated in the CuI-catalyzed N-arylation of nitrogen-containing heterocycles and exhibit much higher catalytic activity and a more extensive structural range of aryl and heteroaryl halides than those exhibited by free L-proline in combination with CuI both in the ionic liquid ([BMIM][BF4]) and in the corresponding homogeneous reaction conditions. The CuI-soaked catalyst 4a-2 can be recycled for nine runs at least without any considerable loss of activity. To the best of our knowledge, our catalytic process is among the most efficient approaches to the N-arylation of imidazoles with aryl halides so far reported. Furthermore, the Pd-soaked material 4a-2 also shows higher catalytic activity in the solvent-free hydrogenation of styrene to ethylbenzene. This new concept is generally applicable and may easily be extended to other supported task-specific ionic liquids.


Assuntos
Aminoácidos/química , Sequestradores de Radicais Livres/química , Compostos Heterocíclicos/síntese química , Líquidos Iônicos/química , Metais Pesados/química , Compostos Organometálicos/química , Catálise , Técnicas de Química Combinatória , Sequestradores de Radicais Livres/síntese química , Compostos Heterocíclicos/química , Estrutura Molecular , Compostos Organometálicos/síntese química , Tamanho da Partícula , Poliestirenos/química , Propriedades de Superfície
6.
J Org Chem ; 72(22): 8535-8, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17902694

RESUMO

Relatively mild and highly efficient CuI-catalyzed N-arylation procedures for nitrogen-containing heterocycles (e.g., imidazoles, benzimidazoles, pyrroles, pyrazoles, indoles, triazoles, etc.) with aryl and heteroaryl halides have been developed. The protocols can be performed easily and tolerate a number of functional groups, such as ester, nitrile, nitro, ketone, free hydroxyl, and free primary amine on the aryl halide.


Assuntos
Derivados de Benzeno/síntese química , Cobre/química , Compostos Heterocíclicos/síntese química , Hidrocarbonetos Halogenados/química , Iodetos/química , Nitrogênio/química , Derivados de Benzeno/química , Catálise , Compostos Heterocíclicos/química , Estrutura Molecular , Estereoisomerismo
7.
J Org Chem ; 72(8): 2737-43, 2007 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-17348708

RESUMO

New (S)-pyrrolidinylmethylimidazole ligands (4a-c) have been readily synthesized in a straightforward fashion from least expensive starting materials in short steps in high yields. Relatively mild and highly efficient CuI-catalyzed N-arylation procedures for imidazoles with aryl and heteroaryl bromides or chlorides have been developed in the presence of 4a and Cs2CO3. It is important to note that the protocol could tolerate functional groups such as ester, nitrile, nitro, ketone, free hydroxyl, and free primary amine on the aryl halide. The protocol could also be applicable to other pi-electron-rich nitrogen heterocycles (pyrrole, pyrazole, indole, benzimidazole, and triazole), affording the N-arylazoles in good to excellent yields.


Assuntos
Cobre/química , Hidrocarbonetos Halogenados/química , Imidazóis/síntese química , Nitrogênio/química , Catálise , Imidazóis/química , Iodetos/química , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirróis/síntese química , Pirróis/química , Triazóis/síntese química , Triazóis/química
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