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1.
Ecotoxicol Environ Saf ; 261: 115104, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37295303

RESUMO

Microplastics (MPs) and the heavy metal cadmium (Cd) have attracted global attention for their toxicological interactions in aquatic organisms. The purpose of this investigation was evaluating the effect of MPs (1 mg L-1) and Cd (5 mg L-1) on the liver function, immune response of crucian carp (Carassius carassius) after 96 h exposure, and intestinal microbiota after 21 days, respectively. Co-exposure to MPs and Cd significantly enhanced MP accumulation in the liver of the crucian carp compared to the accumulation with exposure to MPs alone. Co-exposure to MPs and Cd triggered notable histopathological alterations accompanied by increased hepatic cell necrosis and inflammation, and was associated with higher aspartate aminotransferase and alanine aminotransferase levels, lower superoxide dismutase and catalase activity levels, but higher malondialdehyde content and total antioxidant capacity in the liver. Moreover, the combined treatment of MPs and Cd led to the up-regulated transcription of genes related to immune response, such as interleukin 8 (il-8), il-10, il-1ß, tumor necrosis factor-α, and heat shock protein 70, both in the liver and spleen. Co-exposure to MPs and Cd reduced the variety and abundance of the intestinal microbiota in the crucian carp. Our research indicates that the combined exposure to MPs and Cd may exert synergistic toxic effects on crucian carp, which could impede the sustainable growth of the aquaculture industry and pose potential risks to food safety.


Assuntos
Carpas , Microbioma Gastrointestinal , Poluentes Químicos da Água , Animais , Cádmio/toxicidade , Carpas/metabolismo , Microplásticos , Plásticos/toxicidade , Antioxidantes/metabolismo , Fígado/metabolismo , Imunidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
2.
J Craniofac Surg ; 32(2): e167-e171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33705062

RESUMO

ABSTRACT: The calcifying epithelial odontogenic tumor (CEOT) is a rare benign odontogenic tumor, which usually presents with distension of affected tissues. Radiologically, the lesions are often associated with an unerupted tooth and may have spot calcification shadows. The authors report a case of a CEOT in a 48-year-old male involving the right mandibular jaw bone and mentum soft tissues. The authors performed hemimandibulectomy and enucleation followed by reconstruction of the mandible using a vascularized free fibular flap through a digital surgical technique in order to restore the patient's facial symmetry and prepare the area for functional restorations. The case illustrates who the free fibular flap graft can be used for satisfactory mandibular reconstruction and restoration of the morphology and functions.


Assuntos
Retalhos de Tecido Biológico , Neoplasias Mandibulares , Reconstrução Mandibular , Tumores Odontogênicos , Neoplasias Cutâneas , Fíbula/cirurgia , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Pessoa de Meia-Idade , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia
3.
Acc Chem Res ; 52(2): 367-378, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30653298

RESUMO

Self-assembled nanomaterials show potential high efficiency as theranostic agents for high-performance imaging and therapy. However, superstructures and properties of preassembled nanomaterials are somewhat compromised under complicated physiological conditions. Given the advantages of the dynamic nature and adaptive behavior of self-assembly systems, we propose an "in vivo self-assembly" strategy for in situ construction of nanomaterials in living objects. For the proof-of-concept study of in vivo self-assembly, we developed a bispyrene (BP) molecule as a multifunctional building block. BP molecules show nonfluorescence in the monomeric state. Quantum-chemical calculations indicate that BP forms twisted intramolecular charge transfer states, which are separated into two orthogonal units, preventing the fluorescence emission. Interestingly, the typical excimeric emission of BP is observed with the formation of J-type aggregates, as confirmed by single-crystal X-ray diffraction. Packing of the BP molecules generates parallel pyrene units that interact with adjacent ones in a slipped face-to-face fashion through intermolecular π-π interactions. BP and/or its amphiphilic derivatives are capable of self-aggregating into nanoparticles (NPs) in aqueous solution because of the hydrophobic and π-π interactions of BP. Upon specific biological stimuli, BP NPs can be transformed into variable self-assembled superstructures. Importantly, the self-assembled BP NPs exhibit turn-on fluorescence signals that can be used to monitor the self-assembly/disassembly process in vitro and in vivo. On the basis of the photophysical properties of BP and its aggregates, we synthesized a series of designed BP derivatives as building blocks for in situ construction of functional nanomaterials for bioimaging and/or therapeutics. We observed several new biomedical effects, e.g., (i) the assembly/aggregation-induced retention (AIR) effect, which shows improved accumulation and retention of bioactive nanomaterials in the regions of interests; (ii) the transformation-induced surface adhesion (TISA) effect, which means the BP NPs transform into nanofibers (NFs) on cell surfaces upon binding with specific receptors, which leads to less uptake of BP NPs by cells via traditional endocytosis pathway; and (iii) transformation of the BP NPs into NFs in the tumor microenvironment, showing high accumulation and long-term retention, revealing the transformation-enhanced accumulation and retention (TEAR) effect. In this Account, we summarize the fluorescence property and emission mechanism of BP building blocks upon aggregation in the biological environment. Moreover, BP-derived compounds used for in vivo self-assembly and transformation are introduced involving modulation strategies. Subsequently, unexpected biomedical effects and applications for theranostics of BP based nanomaterials are discussed. We finally conclude with an outlook toward future developments of BP-based self-assembled nanomaterials.


Assuntos
Corantes Fluorescentes/uso terapêutico , Nanofibras/uso terapêutico , Nanopartículas/uso terapêutico , Pirenos/uso terapêutico , Sequência de Aminoácidos , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Humanos , Nanofibras/química , Nanopartículas/química , Polímeros/química , Polímeros/uso terapêutico , Pirenos/síntese química , Pirenos/química , Nanomedicina Teranóstica/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Medicine (Baltimore) ; 99(50): e23590, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327322

RESUMO

RATIONALE: Cutaneous perforators of peroneal vessels are divided into proximal and distal perforators on the basis of perforator distributions and musculocutaneous or septocutaneous properties. The traditional fibular osteocutaneous free flap is raised over the distal two-thirds of the fibula with a skin paddle based on distal perforators, which is affixed to the posterior crural septum. However, the skin pedicle may not be available due to anatomic variations or intraoperative injuries. Herein, because of the absence of distal perforators, we reserved and expropriated proximal perforators originating from the musculocutaneous branch of the superior part of the peroneal artery before it divided into nutrient and arcuate arteries and successfully harvested a separate osteal fibula and proximal perforator skin paddle with a single vascular pedicle-peroneal vessel. PATIENT CONCERNS: A 62-year-old man with a 6-month history of mandibular swelling and soft tissue invasion was referred to us. DIAGNOSIS: Panoramic radiography and computed tomography showed an irregular radiolucent lesion of the mandibular body, and histopathological analysis confirmed a follicular-pattern ameloblastoma. INTERVENTIONS: The diseased mandible and soft tissue were resected and reconstructed with a vascularized fibular osteal flap with the proximal perforator skin paddle. OUTCOMES: The mandibular contour was successfully restored; the skin paddle in the mouth was in good condition after 8 months of follow-up. LESSONS: The proximal perforator is reliable and practical for supplying a skin paddle and has significant potential for future applications. We recommend reserving the proximal perforator skin paddle as a backup flap when planning to raise a fibula flap, since unavailability or injury of the traditional fibular skin island based on distal perforators occurs frequently. This approach can avoid the exploration for a second donor site, save surgical time, and reduce surgical complexity. Moreover, we anticipate more frequent use of the proximal perforator flap in the future because of its flexibility and large volume, and since it can be combined with the osteal fibula or fibular osteocutaneous flap. However, an understanding of the traits of the proximal perforator and determination of its peroneal origin by computed tomography angiography is crucial for predesigning fibular osteal flaps with a proximal perforator skin paddle.


Assuntos
Ameloblastoma/diagnóstico , Neoplasias Maxilomandibulares/diagnóstico , Mandíbula , Ameloblastoma/complicações , Ameloblastoma/diagnóstico por imagem , Ameloblastoma/cirurgia , Diagnóstico Diferencial , Edema/etiologia , Fíbula , Retalhos de Tecido Biológico , Humanos , Neoplasias Maxilomandibulares/complicações , Neoplasias Maxilomandibulares/diagnóstico por imagem , Neoplasias Maxilomandibulares/cirurgia , Masculino , Pessoa de Meia-Idade , Retalho Perfurante , Procedimentos de Cirurgia Plástica
5.
Int J Biol Macromol ; 138: 433-440, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325503

RESUMO

Lignin peroxidase (LiP) was obtained from Pichia methanolica through heterologous expression. LiP was extracted, purified, and immobilized on Fe3O4@SiO2@polydopamine (PDA) nanoparticles to acquire immobilized LiP. The optimal preparation conditions for immobilized LiP were investigated. Results showed that the immobilization efficiency of immobilized LiP reached 56.37% when the enzyme amount, PDA concentration, and immobilization time were 12 mg, 1.6 mg/mL, and 12 h, respectively. Compared with free LiP, the immobilized LiP showed good thermal stability and storage stability and improved pH tolerance. It also retained more than 30% of its initial activity after 8 cycles, demonstrating its improved reusability. The immobilized LiP demonstrated efficacy of reaction of 100%, 100%, 100%, 100%, 79%, 73%, and 65% for tetracycline, dibutyl phthalate, 5-chlorophenol, phenol, phenanthrene, fluoranthene, and benzo(a)pyrene, respectively, while the inactivated immobilized LiP only adsorbed <25% of phenanthrene and fluoranthene. The dissipation of organic pollutants was a combination of degradation and adsorption, with the former playing a more important role.


Assuntos
Poluentes Ambientais/química , Enzimas Imobilizadas , Indóis/química , Nanopartículas de Magnetita , Compostos Orgânicos/química , Peroxidases/química , Polímeros/química , Dióxido de Silício , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Nanopartículas de Magnetita/química , Estrutura Molecular , Peroxidases/isolamento & purificação , Dióxido de Silício/química , Temperatura
6.
Ultrasonics ; 51(5): 561-70, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21232777

RESUMO

Sensitization in 5XXX aluminum alloys is an insidious problem characterized by the gradual formation and growth of beta phase (Mg(2)Al(3)) at grain boundaries, which increases the susceptibility of alloys to intergranular corrosion (IGC) and intergranular stress-corrosion cracking (IGSCC). The degree of sensitization (DoS) is currently quantified by the ASTM G67 Nitric Acid Mass Loss Test, which is destructive and time consuming. A fast, reliable, and non-destructive method for rapid detection and the assessment of the condition of DoS in AA5XXX aluminum alloys in the field is highly desirable. In this paper, we describe a non-destructive method for measurements of DoS in aluminum alloys with an electromagnetic acoustic transducer (EMAT). AA5083 aluminum alloy samples were sensitized at 100°C with processing times varying from 7days to 30days. The DoS of sensitized samples was first quantified with the ASTM 67 test in the laboratory. Both ultrasonic velocity and attenuation in sensitized specimens were then measured using EMAT and the results were correlated with the DoS data. We found that the longitudinal wave velocity was almost a constant, independent of the sensitization, which suggests that the longitudinal wave can be used to determine the sample thickness. The shear wave velocity and especially the shear wave attenuation are sensitive to DoS. Relationships between DoS and the shear velocity, as well as the shear attenuation have been established. Finally, we performed the data mining to evaluate and improve the accuracy in the measurements of DoS in aluminum alloys with EMAT.


Assuntos
Ligas/química , Alumínio/química , Teste de Materiais/instrumentação , Sistemas Microeletromecânicos/instrumentação , Transdutores , Ultrassonografia/instrumentação , Ligas/análise , Alumínio/análise , Desenho de Equipamento , Análise de Falha de Equipamento
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