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1.
BMC Neurol ; 24(1): 204, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879468

RESUMO

Hypoxia can cause a variety of diseases, including ischemic stroke and neurodegenerative diseases. Within a certain range of partial pressure of oxygen, cells can respond to changes in oxygen. Changes in oxygen concentration beyond a threshold will cause damage or even necrosis of tissues and organs, especially for the central nervous system. Therefore, it is very important to find appropriate measures to alleviate damage. MiRNAs can participate in the regulation of hypoxic responses in various types of cells. MiRNAs are involved in regulating hypoxic responses in many types of tissues by activating the hypoxia-inducible factor (HIF) to affect angiogenesis, glycolysis and other biological processes. By analyzing differentially expressed miRNAs in hypoxia and hypoxia-related studies, as well as the HT22 neuronal cell line under hypoxic stress, we found that the expression of miR-18a was changed in these models. MiR-18a could regulate glucose metabolism in HT22 cells under hypoxic stress by directly regulating the 3'UTR of the Hif1a gene. As a small molecule, miRNAs are easy to be designed into small nucleic acid drugs, so this study can provide a theoretical basis for the research and treatment of nervous system diseases caused by hypoxia.


Assuntos
Glucose , Hipocampo , Subunidade alfa do Fator 1 Induzível por Hipóxia , MicroRNAs , Neurônios , Animais , Humanos , Camundongos , Hipóxia Celular/fisiologia , Linhagem Celular , Glucose/metabolismo , Glucose/deficiência , Hipocampo/metabolismo , Hipocampo/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , MicroRNAs/metabolismo , MicroRNAs/genética , Neurônios/metabolismo
2.
Environ Res ; 262(Pt 2): 119972, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39260721

RESUMO

Photocatalytic property of nano Ag is weak and its enhancement is important to enlarge its application. Herein, a novel strategy of constructing silver g-C3N4 biochar composite (Ag-CN@BC) as photocatalyst is developed and its photocatalytic degradation of bisphenol A (BPA) coupled with peroxydisulfate (PDS) oxidation process is characterized. Characterization result showed that silver was evenly embedded into the g-C3N4 structure of the nitrogen atoms format, impeding agglomeration of Ag by distributing stably on biochar. In optimum condition, BPA of 10 mg/L could be degraded completely at pH of 9.0 with a 0.5 g/L photocatalyst, 2 mM PDS in Ag-CN@BC-2 (Ag/melamine molar ratio of 0.5)/PDS system (99.2%, k = 4.601 h-1). Ag-CN@BC shows superior mineralization ratio in degrading BPA to CO2 and H2O via active radical way, including holes (h⁺), superoxide radicals (•O2⁻), sulfate radicals (SO4•⁻), and hydroxyl radicals (•OH). Proper amount of silver can be dispersed effectively by gC3N4, which is responsible for improving the visible-light absorbing capability and accelerate charge transfer during activation of PDS for BPA degradation, while biochar as carrier in the composite is supposed to enhance the photoelectric degradation of BPA by reducing the band gap and increasing the photocurrent of Ag-CN@BC catalyst. Ag-CN@BC exhibits excellent catalyst stability and photocatalytic activity for treatment of toxic organic contaminants in the environment.

3.
Ecotoxicol Environ Saf ; 271: 115979, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244511

RESUMO

Micro/nanoplastics (M/NPs) in water have raised global concern due to their potential environmental risks. To reestablish a M/NPs free world, enormous attempts have been made toward employing chemical technologies for their removal in water. This review comprehensively summarizes the advances in chemical degradation approaches for M/NPs elimination. It details and discusses promising techniques, including photo-based technologies, Fenton-based reaction, electrochemical oxidation, and novel micro/nanomotors approaches. Subsequently, critical influence factors, such as properties of M/NPs and operating factors, are analyzed in this review specifically. Finally, it concludes by addressing the current challenges and future perspectives in chemical degradation. This review will provide guidance for scientists to further explore novel strategies and develop feasible chemical methods for the improved control and remediation of M/NPs in the future.


Assuntos
Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Plásticos , Microplásticos , Água , Poluentes Químicos da Água/análise
4.
Inorg Chem ; 62(29): 11633-11644, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37439595

RESUMO

Small-pore Lewis acid zeolites have been showing increasing potential in shape-selective reactions regarding small-molecule conversion. In this study, Sn-CHA with tunable framework Sn contents was facilely prepared via a fluoride-free, seed-assisted interzeolite conversion (IZC) pathway. Commercially available dealuminated USY functioned as the parent sample, and seeding played a vital role in accelerating the transformation process, promoting the target zeolite yield, and guiding the attached-growth pathway. Notably, a proto-zeolite phase with a semi-constructed pore structure was captured during the IZC process, which represents a crucial intermediate stage for developing the complete CHA structure and ensuring a well-defined Sn status. The detailed synthesis mechanism was explored in multiscale by a series of techniques. The obtained Sn-CHA and proto-Sn-CHA exhibited excellent catalytic performance in converting 1,3-dihydroxyacetone to methyl lactate. Proto-Sn-CHA was proven to be a highly effective glucose isomerization catalyst owing to its larger pore size and Lewis acidic nature.

5.
Aesthetic Plast Surg ; 47(5): 1957-1966, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37580561

RESUMO

BACKGROUND: The objective of the present study was to assess the hard and soft tissue differences of skeletal Class III malocclusion patients treated with orthodontic-orthognathic surgery treatment between two decompensation approaches including extraction of maxillary premolars in preoperative orthodontics and clockwise rotation of the maxilla in orthognathic surgery. METHODS: 22 skeletal Class III patients with the crowding of maxillary dental arch less than 3mm were included in this study. These patients were divided into two groups: extraction group and non-extraction group. Lateral cephalograms taken before preoperative orthodontic treatment and after postoperative orthodontic treatment were used to analyze the differences of hard and soft tissues between two groups. Independent t test was used to evaluate the differences of variables between extraction group and non-extraction group. RESULTS: After treatment, there was significant difference of Wits between extraction group and non-extraction group (- 4.34 mm vs - 2.82 mm, respectively, P <0.05). Co-Gn was significantly greater in non-extraction group than in extraction group (77.18 mm vs 71.58 mm, P <0.05). U1-SN and L1-MP in extraction group were significantly closer to the normal values than non-extraction group (P <0.05). Regarding the change of variables before and after orthodontic-orthognathic treatment, NLA (7.25° vs 1.46°, P <0.01) and G-Sn-Pog' (8.06° vs 4.62°, P <0.05) were significantly greater in extraction group than in non-extraction group. CONCLUSION: For patients with skeletal Class III malocclusion, extraction of maxillary premolars in preoperative orthodontic treatment can more effectively eliminate the dental compensation and achieve a more harmonious facial profile compared to clockwise rotation of the maxilla in orthognathic surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Má Oclusão Classe III de Angle , Procedimentos Cirúrgicos Ortognáticos , Humanos , Mandíbula/cirurgia , Má Oclusão Classe III de Angle/cirurgia , Maxila/cirurgia , Cefalometria
6.
J Environ Manage ; 344: 118546, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37418916

RESUMO

Biosynthesis of silver nanoparticles (AgNPs) by plant extracts and its antibacterial utilization has attracted great attention due to the spontaneous reducing and capping capacities of phytochemicals. However, the preferential role and mechanisms of the functional phytochemicals from different plants on AgNPs synthesis, and its catalytic and antibacterial performance remain largely unknown. This study used three widespread arbor species, including Eriobotrya japonica (EJ), Cupressus funebris (CF) and Populus (PL), as the precursors and their leaf extracts as reducing and stabilizing agents for the biosynthesis of AgNPs. A total of 18 phytochemicals in leaf extracts were identified by ultra-high liquid-phase mass spectrometer. For EJ extracts, most kinds of flavonoids participated in the generation of AgNPs by a reduced content of 5∼10%, while for CF extracts, about 15∼40% of the polyphenols were consumed to reduce Ag+ to Ag0. Notably, the more stable and homogeneous spherical AgNPs with smaller size (≈38 nm) and high catalytic capacity on Methylene blue were obtained from EJ extracts rather than CF extracts, and no AgNPs were synthesized from PL extracts, indicating that flavonoids are superior than polyphenols to act as reducer and stabilizer in AgNPs biosynthesis. The antibacterial activities against Gram-positive (Staphylococcus aureus and Bacillus mycoides) and Gram-negative bacteria (Pseudomonas putida and Escherichia coli) were higher in EJ-AgNPs than that in CF-AgNPs, which confirmed the synergistic antibacterial effects of flavonoids combined with AgNPs in EJ-AgNPs. This study provides a significant reference on the biosynthesis of AgNPs with efficient antibacterial utilization underlying effect of abundant flavonoids in plant extracts.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Prata/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Polifenóis , Flavonoides , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana
7.
J Craniofac Surg ; 32(3): 883-887, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33038180

RESUMO

ABSTRACT: This study summarized the literature regarding the application of pre-bent titanium miniplates in orthognathic surgery and evaluated the extra deformation of the manually pre-bent titanium miniplates via finite element analysis for acquiring higher surgical accuracy. The literature was reviewed with a chart. Three models of titanium miniplates with different thicknesses (1.0 mm, 0.8 mm, 0.6 mm) were created using COMSOL Multiphysics software for biomechanical behavior analysis. The 3 models were virtually bent into 5 angles (15 degree, 30 degree, 45 degree, 60 degree, 80 degree). respectively to simulate the preoperative virtual bending, then to simulate the practical manual bending via finite element analysis. The stresses and displacements of these models were recorded. The models from virtual bending simulation and manual bending simulation were registered to analyze the deviations. The results showed that the maximum stress and the displacement deviations between the virtual bending models and the manual bending models increased with the thickness and bending angle of the pre-bent miniplate models. To improve the surgical accuracy, measures should be applied to the manually pre-bent titanium miniplates to reduce the extra deformation when the plate being thicker and the bending angle being larger.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Placas Ósseas , Análise de Elementos Finitos , Fixação Interna de Fraturas , Humanos , Estresse Mecânico , Titânio
8.
J Craniofac Surg ; 31(8): 2193-2198, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33136853

RESUMO

The aim of this study is to evaluate the osteogenesis around titanium implant and in bone defect or fracture in jaw bones and long bones in ovariectomized (OVX) animal models. The literature on the osteogenesis around titanium implant and in bone defect or fracture in jaw bones and long bones was reviewed with charts. Fourty-eight rats were randomly divided into OVX group with ovariectomy and SHAM (sham-surgery) group with sham surgery. Titanium implants were inserted in the right mandibles and tibiae; bone defects were created in the left mandibles and tibiae. Two-week postoperatively, mandibles and tibiae of 8 rats were harvested and examined by hematoxylin and eosin staining and histological analysis; 4-week postoperatively, all mandibles and tibiae were harvested and examined by Micro-CT and histological analysis. A total of 52 articles were included in this literature review. Tibial osteogenesis around titanium implant and in bone defect in OVX group were significantly decreased compared with SHAM group. However, osteogenesis differences in the mandible both around titanium implant and in bone defect between groups were not statistically significant. OVX-induced osteoporosis suppresses osteogenesis around titanium implant and in the bone defect or fracture in long bones significantly while has less effect on that in the jaw bones.


Assuntos
Implantes Experimentais/efeitos adversos , Arcada Osseodentária/efeitos dos fármacos , Tíbia/efeitos dos fármacos , Titânio/farmacologia , Animais , Feminino , Procedimentos Cirúrgicos Ortognáticos , Osteogênese/efeitos dos fármacos , Osteoporose/induzido quimicamente , Osteoporose/patologia , Ovariectomia , Ratos , Tíbia/cirurgia
9.
Med Sci Monit ; 25: 248-258, 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30618455

RESUMO

BACKGROUND Metaplastic breast cancer (MBC) is a rare type of breast cancer, characterized histologically by the presence of two or more malignant cell types (epithelial and mesenchymal). This retrospective study aimed to review the imaging and histological features of MBC, with a review of the literature. MATERIAL AND METHODS Nineteen patients with MBC (age range, 28-75 years; mean, 55 years) underwent review of their clinical records, histopathology, immunohistochemistry, and imaging findings, which included mammography, sonography, and magnetic resonance imaging (MRI) with T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and diffusion restriction determined by the apparent diffusion coefficient (ADC) and a time-intensity curve (TIC) for signal intensity. RESULTS The mammographic features of MBC were oval shaped (54.5%), with indistinct margin (45.5%), and high tumor density (72.7%), and on sonography, they were oval shaped (57.1%), with hypo-echogenic areas (85.8%). On MRI, MBC showed moderate hyper-intensity with a high signal intensity in the center of the tumor on T2WI (100%), an indistinct margin (75.0%), and rim enhancement (58.3%). Using a TIC, the early phase showed rapid enhancement, and the delay phase showed a signal plateau (91.7%). DWI showed diffusion restriction in all cases determined by the ADC. Immunohistochemistry showed negative expression of estrogen receptor (ER) (91.0%), progesterone receptor (PR) (81%), and HER2 (erbB-2) (80.0%). CONCLUSIONS Imaging features of MBC on mammography and ultrasound were benign. The use of T2WI MRI showed characteristic features of signal intensity using TIC curve and ADC analysis, which may support biopsy and histological analysis for definitive diagnosis.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Biópsia/métodos , China , Meios de Contraste , Feminino , Humanos , Imuno-Histoquímica/métodos , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Metaplasia/diagnóstico por imagem , Metaplasia/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
J Med Genet ; 51(3): 185-96, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24431331

RESUMO

INTRODUCTION: Lenz microphthalmia syndrome (LMS) is a genetically heterogeneous X-linked disorder characterised by microphthalmia/anophthalmia, skeletal abnormalities, genitourinary malformations, and anomalies of the digits, ears, and teeth. Intellectual disability and seizure disorders are seen in about 60% of affected males. To date, no gene has been identified for LMS in the microphthalmia syndrome 1 locus (MCOPS1). In this study, we aim to find the disease-causing gene for this condition. METHODS AND RESULTS: Using exome sequencing in a family with three affected brothers, we identified a mutation in the intron 7 splice donor site (c.471+2T→A) of the N-acetyltransferase NAA10 gene. NAA10 has been previously shown to be mutated in patients with Ogden syndrome, which is clinically distinct from LMS. Linkage studies for this family mapped the disease locus to Xq27-Xq28, which was consistent with the locus of NAA10. The mutation co-segregated with the phenotype and cDNA analysis showed aberrant transcripts. Patient fibroblasts lacked expression of full length NAA10 protein and displayed cell proliferation defects. Expression array studies showed significant dysregulation of genes associated with genetic forms of anophthalmia such as BMP4, STRA6, and downstream targets of BCOR and the canonical WNT pathway. In particular, STRA6 is a retinol binding protein receptor that mediates cellular uptake of retinol/vitamin A and plays a major role in regulating the retinoic acid signalling pathway. A retinol uptake assay showed that retinol uptake was decreased in patient cells. CONCLUSIONS: We conclude that the NAA10 mutation is the cause of LMS in this family, likely through the dysregulation of the retinoic acid signalling pathway.


Assuntos
Anoftalmia/genética , Microftalmia/genética , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Transdução de Sinais/genética , Tretinoína/metabolismo , Anoftalmia/fisiopatologia , Proliferação de Células , Células Cultivadas , Feminino , Fibroblastos , Humanos , Masculino , Microftalmia/fisiopatologia , Mutação/genética , Linhagem , Fenótipo , Sítios de Splice de RNA/genética
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