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1.
Environ Res ; 244: 117927, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103778

RESUMO

BACKGROUND: Ambient fine particulate matter (PM2.5) exposure has been associated with an increased risk of gastrointestinal cancer mortality, but the attributable constituents remain unclear. OBJECTIVES: To investigate the association of long-term exposure to PM2.5 constituents with total and site-specific gastrointestinal cancer mortality using a difference-in-differences approach in Jiangsu province, China during 2015-2020. METHODS: We split Jiangsu into 53 spatial units and computed their yearly death number of total gastrointestinal, esophagus, stomach, colorectum, liver, and pancreas cancer. Utilizing a high-quality grid dataset on PM2.5 constituents, we estimated 10-year population-weighted exposure to black carbon (BC), organic carbon (OC), sulfate, nitrate, ammonium, and chloride in each spatial unit. The effect of constituents on gastrointestinal cancer mortality was assessed by controlling time trends, spatial differences, gross domestic product (GDP), and seasonal temperatures. RESULTS: Overall, 524,019 gastrointestinal cancer deaths were ascertained in 84.77 million population. Each interquartile range increment of BC (0.46 µg/m3), OC (4.56 µg/m3), and nitrate (1.41 µg/m3) was significantly associated with a 27%, 26%, and 34% increased risk of total gastrointestinal cancer mortality, respectively, and these associations remained significant in PM2.5-adjusted models and constituent-residual models. We also identified robust associations of BC, OC, and nitrate exposures with site-specific gastrointestinal cancer mortality. The mortality risk generally displayed increased trends across the total exposure range and rose steeper at higher levels. We did not identify robust associations for sulfate, ammonium, or chlorine exposure. Higher mortality risk ascribed to constituent exposures was identified in total gastrointestinal and liver cancer among women, stomach cancer among men, and total gastrointestinal and stomach cancer among low-GDP regions. CONCLUSIONS: This study offers consistent evidence that long-term exposure to PM2.5-bound BC, OC, and nitrate is associated with total and site-specific gastrointestinal cancer mortality, indicating that these constituents need to be controlled to mitigate the adverse effect of PM2.5 on gastrointestinal cancer mortality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Compostos de Amônio , Neoplasias Gástricas , Masculino , Feminino , Humanos , Material Particulado/toxicidade , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Exposição Ambiental/efeitos adversos , Nitratos/toxicidade , China/epidemiologia , Carbono , Fuligem , Sulfatos , Poluição do Ar/efeitos adversos
2.
J Immunol ; 207(6): 1683-1693, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34400525

RESUMO

Alveolar macrophages (AMs) play critical roles in maintaining lung homeostasis and orchestrating the immune responses. Although the essential factors known for AM development have been identified, currently an optimal in vitro culture system that can be used for studying the development and functions of AMs is still lacking. In this study, we report the development of an optimized culture system for generating AM-like cells from adult mouse bone marrow and fetal liver cells on in vitro culture in the presence of a combination of GM-CSF, TGF-ß, and peroxisome proliferator-activated receptor γ (PPAR-γ) agonist rosiglitazone. These AM-like cells expressed typical AM surface markers sialic acid-binding Ig-like lectin-F (Siglec-F), CD11c, and F4/80, and AM-specific genes, including carbonic anhydrase 4 (Car4), placenta-expressed transcript 1 (Plet1), eosinophil-associated RNase A family member 1 (Ear1), cell death-inducing DNA fragmentation factor A-like effector c (Cidec), and cytokeratin 19 (Krt19). Similar to primary AMs, the AM-like cells expressed alternative macrophage activation signature genes and self-renewal genes. Moreover, this culture system could be used for expansion of bronchoalveolar lavage fluid-derived AMs in vitro. The AM-like cells generated from bone marrow resembled the expanded bronchoalveolar lavage fluid-derived AMs in inflammatory responses and phagocytic activity. More importantly, these AM-like cells could be obtained in sufficient numbers that allowed genetic manipulation and functional analysis in vitro. Taken together, we provide a powerful tool for studying the biology of AMs.


Assuntos
Pulmão , Macrófagos Alveolares , Animais , Líquido da Lavagem Broncoalveolar , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta
3.
BMC Musculoskelet Disord ; 24(1): 928, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041036

RESUMO

BACKGROUND: New-onset neurological symptoms such as numbness and pain in lower extremities might appear immediately after conventional lumbar interbody fusion (LIF) surgery performed in patients with lumbar spinal stenosis. METHODS AND ANALYSIS: This is a multicenter, randomized, open-label, parallel-group, active-controlled trial investigating the clinical outcomes of modified LIF sequence versus conventional LIF sequence in treating patients with lumbar spinal stenosis. A total of 254 eligible patients will be enrolled and randomized in a 1:1 ratio to either modified LIF sequence or conventional LIF sequence group. The primary outcome measure is the perioperative incidence of new-onset lower extremity neurological symptoms, including new adverse events of pain, numbness, and foot drop of any severity. Important secondary endpoints include visual analogue scale (VAS) pain score and lumbar Japanese Orthopaedic Association (JOA) recovery rate. Other safety endpoints will also be evaluated. The safety set used for safety data analysis by the actual surgical treatment received and the full analysis set for baseline and efficacy data analyses according to the intent-to-treat principle will be established as the two analysis populations in the study. CONCLUSION: This study is designed to investigate the clinical outcomes of modified LIF sequences in patients with lumbar spinal stenosis. It aims to provide clinical evidence that the modified "fixation-fusion" sequence of LIF surgery is effective in treating lumbar spinal stenosis. TRIAL REGISTRATION: http://www.chictr.org.cn/index.aspx ID: ChiCTR2100048507.


Assuntos
Fusão Vertebral , Estenose Espinal , Humanos , Estenose Espinal/cirurgia , Estenose Espinal/etiologia , Resultado do Tratamento , Hipestesia/etiologia , Vértebras Lombares/cirurgia , Dor/etiologia , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Estudos Retrospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
4.
J Appl Clin Med Phys ; 24(6): e13937, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36992637

RESUMO

PURPOSE: Uterine fibroid is the most common benign tumor in female reproductive organs. In order to guide the treatment, it is crucial to detect the location, shape, and size of the tumor. This study proposed a deep learning approach based on attention mechanisms to segment uterine fibroids automatically on preoperative Magnetic Resonance (MR) images. METHODS: The proposed method is based on U-Net architecture and integrates two attention mechanisms: channel attention of squeeze-and-excitation (SE) blocks with residual connections, spatial attention of pyramid pooling module (PPM). We did the ablation study to verify the performance of these two attention mechanisms module and compared DARU-Net with other deep learning methods. All experiments were performed on a clinical dataset consisting of 150 cases collected from our hospital. Among them, 120 cases were used as the training set, and 30 cases are used as the test set. After preprocessing and data augmentation, we trained the network and tested it on the test dataset. We evaluated segmentation performance through the Dice similarity coefficient (DSC), precision, recall, and Jaccard index (JI). RESULTS: The average DSC, precision, recall, and JI of DARU-Net reached 0.8066 ± 0.0956, 0.8233 ± 0.1255, 0.7913 ± 0.1304, and 0.6743 ± 0.1317. Compared with U-Net and other deep learning methods, DARU-Net was more accurate and stable. CONCLUSION: This work proposed an optimized U-Net with channel and spatial attention mechanisms to segment uterine fibroids on preoperative MR images. Results showed that DARU-Net was able to accurately segment uterine fibroids from MR images.


Assuntos
Leiomioma , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Hospitais , Processamento de Imagem Assistida por Computador
5.
Int J Mol Sci ; 24(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569417

RESUMO

The aim of this study is to investigate the effect of dietary protein levels on flesh quality, oxidative stress, and autophagy status in the muscles of triploid crucian carp (Carassius carassius triploid), and the related molecular mechanisms. Six experimental diets with different protein levels (26%, 29%, 32%, 35%, 38%, 41%) were formulated. A total of 540 fish with an initial weight of 11.79 ± 0.09 g were randomly assigned to 18 cages and six treatments with three replicates of 30 fish each for 8 weeks feeding. It could be found that the whole-body ash content significantly increased in high protein level groups (p < 0.05). The 29% dietary protein level group exhibited the highest muscle moisture, although there was an inconspicuous decrease in the chewiness of the muscles when compared with the other groups. The dietary protein level influenced the content of free amino acids and nucleotides, especially the content of flavor amino acids, which exhibited an increasing tendency along with the increasing protein level, such as alanine and glutamic acid, while the flavor nucleotides showed different fluctuation trends. Moreover, the genes related to muscle development were shown to be influenced by the dietary protein level, especially the expression of MRF4, which was up-regulated with the increasing dietary protein levels. The 29% dietary protein level promoted the majority of analyzed muscle genes expression to the highest level when compared to other dietary levels, except the Myostain, whose expression reached its highest at 38% dietary protein levels. Furthermore, the effect of dietary protein levels on antioxidant signaling pathway genes were also examined. High protein levels would boost the expression of GSTα; GPX1 and GPX4α mRNA expression showed the highest level at the 32% dietary protein group. The increasing dietary protein level decreased both mRNA and protein expressions of Nrf2 by up-regulating Keap1. Autophagy-related gene expression levels reached the peak at 32% dietary protein level, as evidenced by a similar change in protein expression of FoxO1. In summary, muscle nutritional composition, antioxidative pathways, and autophagy levels were affected by the dietary protein levels. A total of 29-32% dietary protein level would be the appropriate level range to improve muscle quality and promote the antioxidant and autophagy capacity of triploid crucian carp muscles.

6.
BMC Cancer ; 22(1): 776, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35840910

RESUMO

BACKGROUND: To investigate the differences in HPV genotypes and clinical indicators between cervical squamous cell carcinoma and adenocarcinoma and to identify independent predictors for differentiating cervical squamous cell carcinoma and adenocarcinoma. METHODS: A total of 319 patients with cervical cancer, including 238 patients with squamous cell carcinoma and 81 patients with adenocarcinoma, were retrospectively analysed. The clinical characteristics and laboratory indicators, including HPV genotypes, SCCAg, CA125, CA19-9, CYFRA 21-1 and parity, were analysed by univariate and multivariate analyses, and a classification model for cervical squamous cell carcinoma and adenocarcinoma was established. The model was validated in 96 patients with cervical cancer. RESULTS: There were significant differences in SCCAg, CA125, CA19-9, CYFRA 21-1, HPV genotypes and clinical symptoms between cervical squamous cell carcinoma and adenocarcinoma (P < 0.05). Logistic regression analysis showed that SCCAg and HPV genotypes (high risk) were independent predictors for differentiating cervical squamous cell carcinoma from adenocarcinoma. The AUC value of the established classification model was 0.854 (95% CI: 0.804-0.904). The accuracy, sensitivity and specificity of the model were 0.846, 0.691 and 0.899, respectively. The classification accuracy was 0.823 when the model was verified. CONCLUSION: The histological type of cervical cancer patients with persistent infection of high-risk HPV subtypes and low serum SCCAg levels was more prone to being adenocarcinoma. When the above independent predictors occur, the occurrence and development of cervical adenocarcinoma should be anticipated, and early active intervention treatment should be used to improve the prognosis and survival of patients.


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Papillomaviridae , Infecções por Papillomavirus , Serpinas , Neoplasias do Colo do Útero , Antígenos de Neoplasias , Antígeno CA-19-9 , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Feminino , Genótipo , Humanos , Queratina-19 , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Estudos Retrospectivos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
7.
Cell Commun Signal ; 20(1): 92, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715860

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer with poor prognosis and limited treatment. As a major component of the tumor microenvironment, tumor-associated macrophages (TAMs) play an important role in facilitating the aggressive behavior of TNBC. This study aimed to explore the novel mechanism of TAMs in the regulation of epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) properties in TNBC. METHODS: Expression of the M2-like macrophage marker CD163 was evaluated by immunohistochemistry in human breast cancer tissues. The phenotype of M2 macrophages polarized from Tohoku-Hospital-Pediatrics-1 (THP1) cells was verified by flow cytometry. Transwell assays, wound healing assays, western blotting, flow cytometry, ELISA, quantitative polymerase chain reaction (qPCR), luciferase reporter gene assays, and immunofluorescence assays were conducted to investigate the mechanism by which TAMs regulate EMT and CSC properties in BT549 and HCC1937 cells. RESULTS: Clinically, we observed a high infiltration of M2-like tumor-associated macrophages in TNBC tissues and confirmed that TAMs were associated with unfavorable prognosis in TNBC patients. Moreover, we found that conditioned medium from M2 macrophages (M2-CM) markedly promoted EMT and CSC properties in BT549 and HCC1937 cells. Mechanistically, we demonstrated that chemokine (C-C motif) ligand 2 (CCL2) secretion by TAMs activated Akt signaling, which in turn increased the expression and nuclear localization of ß-catenin. Furthermore, ß-catenin knockdown reversed TAM-induced EMT and CSC properties. CONCLUSIONS: This study provides a novel mechanism by which TAMs promote EMT and enhance CSC properties in TNBC via activation of CCL2/AKT/ß-catenin signaling, which may offer new strategies for the diagnosis and treatment of TNBC. Video Abstract.


Assuntos
Quimiocina CCL2 , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas , Proteínas Proto-Oncogênicas c-akt , Neoplasias de Mama Triplo Negativas , Macrófagos Associados a Tumor , beta Catenina , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Quimiocina CCL2/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , beta Catenina/metabolismo
8.
Langmuir ; 38(13): 4147-4155, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35315273

RESUMO

In this work, we studied the formation and properties of composite films coassembled by cellulose nanocrystals (CNCs) and bovine serum albumin-stabilized gold nanoclusters (BSA-AuNCs). The influences of the BSA-AuNC concentration on the structure and optical properties of CNC-based composite films were further studied. It was found that the composite film retained the chiral nematic structure and optical activity. The self-assembled CNC and BSA-AuNC helical superstructures can produce strong, left-handed, circularly polarized luminescence with dissymmetry factors up to 0.287. Meanwhile, the third component, polyethylene glycol, was introduced without affecting the structural color and fluorescence characteristics of the composite film to enhance the flexibility of the film. The simplicity of the film preparation, the abundance of CNCs, and the flexibility and stability of the composite films pave the way for the production of functional materials with integrated functions.


Assuntos
Celulose , Nanopartículas , Celulose/química , Ouro/química , Luminescência , Nanopartículas/química , Óptica e Fotônica
9.
Langmuir ; 38(42): 12849-12858, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36215031

RESUMO

In this study, we construct a green and high-performance platform using Pickering emulsions for biphasic catalysis. The oil-in-water Pickering emulsions stabilized by the lignin/chitosan nanoparticles (Lig/Chi NPs) have great stability and alkali resistance, showing pH-responsive reversible emulsification and demulsification which can be recycled at least three times. The Pickering emulsion also has fluorescence and wide availability to different oil-to-water volume ratios, types of oil, storage times, temperatures, and ion concentrations. When this system is applied to the lipase-catalyzed reaction for the hydrolysis of p-nitrophenol palmitate, it will provide stable and large oil-water reaction interface areas, and the negatively charged lipase will enrich at the emulsion interface by electrostatic adsorption of the positively charged Lig/Chi NPs to achieve immobilization (lipase-Lig/Chi NPs). The reaction conversion rate can reach nearly 100% in 30 min, which is nearly three times higher than that of the conventional two-phase system. Moreover, the lipases in Pickering emulsion stabilized by Lig/Chi NPs exhibit great recyclability because of the protection of Lig/Chi NPs.


Assuntos
Quitosana , Nanopartículas , Emulsões , Lignina , Catálise , Lipase , Água , Álcalis , Palmitatos , Tamanho da Partícula
10.
Fish Shellfish Immunol ; 120: 82-91, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34780976

RESUMO

Mitogen-activated protein kinase kinase kinase 4 (MAP3K4) is a multifunctional mediator of the conserved MAPK signaling pathway that plays essential roles in the regulation of immune responses in mammals. However, the function of teleost MAP3K4s in innate immunity, especially in the intestinal immune system, is still poorly understood. In the current study, we identified a fish MAP3K4 homolog (CiMAP3K4) in Ctenopharyngodon idella as well as its immune function in intestine following bacterial infection in vivo and in vitro. The open reading frame (ORF) of CiMAP3K4 encodes putative peptide of 1544 amino acids containing a predicted serine/threonine protein kinase (S_TKc) domain with high identity with other fish MAP3K4s. Phylogenetic analysis revealed the CiMAP3K4 belonged to the fish cluster and showed the closest relationship to Pimephales promelas. Quantitative real-time PCR (qRT-PCR) analysis revealed that CiMAP3K4 transcripts were widely distributed in all tested tissues, especially with high expression in the muscle and intestine of healthy grass carp. In vitro, CiMAP3K4 gene expression was upregulated by bacterial PAMPs (lipolysaccharide (LPS), peptidoglycan (PGN), L-Ala-γ-D-Glu-meso-diaminopimelic acid (Tri-DAP) and muramyl dipeptide (MDP)) and pathogens (Aeromonas hydrophila and Aeromonas veronii) in primary intestinal cells. In vivo, the mRNA expression levels of CiMAP3K4 in the intestine were significantly induced by bacterial MDP challenge in a time-dependent manner; however, this effect could be inhibited by the bioactive dipeptides ß-alanyl-l-histidine (carnosine) and alanyl-glutamine (Ala-Gln). Moreover, CiMAP3K4 was located primarily in the cytoplasm, and its overexpression increased the transcriptional activity of AP-1 in HEK293T cells. Collectively, these results suggested that CiMAP3K4 might play an important role in the intestinal immune response to bacterial infections, which paves the way for a better understanding of the intestinal immune system of grass carp.


Assuntos
Carpas , Doenças dos Peixes , Proteínas de Peixes , Infecções por Bactérias Gram-Negativas , MAP Quinase Quinase Quinase 4 , Aeromonas hydrophila , Animais , Carpas/genética , Carpas/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Células HEK293 , Humanos , Imunidade Inata/genética , Intestinos/imunologia , Intestinos/microbiologia , MAP Quinase Quinase Quinase 4/genética , Filogenia
11.
Anal Bioanal Chem ; 414(16): 4645-4654, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35441260

RESUMO

The surface-enhanced Raman scattering (SERS) technique has displayed a broad application prospect in disease diagnosis owing to its high sensitivity, fast responsiveness, and high specificity. In this study, we developed a SERS-based immunoassay for the detection of cryptococcal capsular polysaccharide (glucuronoxylomannan, GXM), which is an important biomarker of cryptococcosis. The coupled localized surface plasmon resonance effect between magnetic SERS substrates and SERS tags gave rise to an enhanced Raman signal upon the formation of sandwich complexes, which contributes to the sensitive and specific detection of GXM. As a result, the developed method provided a lower limit of detection (1.25 ng/mL) than conventional methods, such as latex agglutination, lateral flow assay, and enzyme-linked immunosorbent assay. Additionally, a recovery experiment was performed to detect GXM in human serum, which also validated the potential advantages of a SERS-based immunoassay in the clinical diagnosis of cryptococcosis.


Assuntos
Criptococose , Nanopartículas Metálicas , Biomarcadores , Criptococose/diagnóstico , Ensaio de Imunoadsorção Enzimática , Ouro/química , Humanos , Imunoensaio/métodos , Nanopartículas Metálicas/química , Análise Espectral Raman/métodos
12.
Nano Lett ; 21(15): 6406-6415, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34014681

RESUMO

Self-assembled peptide materials with sequence-encoded properties have attracted great interest. Despite their intrinsic chirality, the generation of circularly polarized luminescence (CPL) based on the self-assembly of simple peptides has been rarely reported. Here, we report the self-assembly of peptides into hierarchical helical arrays (HHAs) with controlled supramolecular handedness. The HHAs can emit full-color CPL signals after the incorporation of various achiral fluorescent molecules, and the glum value is 40 times higher than that of the CPL signal from the solutions. By simply changing the amino acid sequence of the peptides, CPL signals with opposite handedness can be generated within the HHAs. The peptide HHAs can provide hydrophobic pockets to accommodate the fluorescent molecules with helical arrangement through strong aromatic stacking interactions, which are responsible for the CPL signals. This work provides a pathway to construct highly ordered chiral materials, which have broad applications in the chiroptical field.


Assuntos
Luminescência , Peptídeos
13.
J Environ Manage ; 322: 116077, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36055098

RESUMO

To optimize the efficiency of general adsorption-Fenton oxidation treatment, iron-loaded granular activated carbon (Fe-GAC) was prepared, characterized, and used as a catalyst in the heterogeneous Fenton oxidation of tetracycline (TC). Characterization revealed that the Fe(II) was successfully introduced onto the original granular activated carbon (GAC) and diversified the materials' surface morphology and elemental compounds. Under an initial pH of 3.0, the Fe-GAC/Fenton system obtained a maximum removal rate of 92.6%, with hydrogen peroxide (H2O2) dosages of 9 mmol g-1. And the GAC/Fenton without iron supplementation was 89.5%, with H2O2 dosages of 8 mmol g-1. Additionally, the Fe-GAC/Fenton system consumed a lower Fe(II) dosage than GAC/Fenton, with Fe(II)/H2O2 molar ratios of 0.007:1 and 0.04:1, respectively. Analysis of total organic carbon demonstrated higher mineralization efficiency in the Fe-GAC/Fenton system (67.2%), which was approximately 1.3 times of GAC/Fenton. Desorption experiments showed that the adsorption and degradation accounted for 19.22% and 80.78% of the total TC removal by GAC/Fenton, and 10.58% and 89.42% in the Fe-GAC/Fenton system, respectively. Electron paramagnetic resonance (EPR) technique and quenching experiments demonstrated that the dominant reactive oxygen species (ROS) in synergistic treatments were hydroxyl (•OH) and hydroxy peroxyl (HO2•) radicals. In addition, three potential degradation pathways for TC were proposed according to the detected fourteen intermediates. Catalyst regeneration treatments were evaluated over six cycles, and the regeneration was 6.5% higher with the iron-supplemented carbon granules. Overall, the Fe-GAC can be used as an efficient catalyst in practical water treatment, and this study demonstrated a promising method to develop adsorption-Fenton technology.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Antibacterianos , Catálise , Carvão Vegetal/química , Compostos Ferrosos/química , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução , Espécies Reativas de Oxigênio , Tetraciclina , Poluentes Químicos da Água/química
14.
Biochem Biophys Res Commun ; 547: 192-197, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33618226

RESUMO

In this study, we aimed to develop B. subtilis spore coat protein A (CotA) for the enzymatic determination of bilirubin. Firstly, molecular docking and oxidation kinetic analysis confirmed the feasibility of CotA for oxidizing bilirubin. Secondly, CotA showed pH-preferable oxidization performance to direct bilirubin (DB) in acidic conditions and an alkaline-catalytic oxidation capacity to total bilirubin (TB). Mechanism analysis results confirm that the conformational changes of CotA, DB and UB caused by pH changes are responsible for the selective oxidation of DB and TB by CotA. Then, CotA exhibits better structural characteristics and enzymatic performance than M. verrucaria-derived bilirubin oxidase (Mv-BOD). Besides, the strong anti-interference ability helps CotA adapt to complex catalytic environment in the detection of DB and TB. Our results prove that CotA can be used as a promising candidate bio-enzymatic detection reagent for DB and TB.


Assuntos
Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Bilirrubina/análise , Ensaios Enzimáticos/métodos , Lacase/metabolismo , Proteínas de Bactérias/química , Bilirrubina/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lacase/química , Simulação de Acoplamento Molecular , Oxirredução
15.
Chemistry ; 27(4): 1423-1429, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33169438

RESUMO

The development of highly efficient metal-free electrocatalysts for the oxygen reduction reaction (ORR) has attracted great attention for the creation of electrochemical energy devices. In this study, one-dimensional (1 D) fullerene nanofibers prepared from liquid-liquid interfacial precipitation are first fabricated into fullerene-derived carbon nanofiber films (FCNFs) through a simple filtration procedure. Then, pyrolysis of the FCNFs in the presence of ammonia and sulfur produces N- and S-co-doped porous carbon nanofiber films (N,S-PCNFs). As excellent metal-free electrocatalysts for the ORR, N,S-PCNFs exhibit remarkable catalytic activity, superior stability, and excellent methanol tolerance in both alkaline and acidic solution. Such a high ORR performance benefits from the robust porous nanofiber network structure with high concentrations of active N- and S- groups and abundant defects. Notably, upon practical use of N,S-PCNFs as catalysts in Zn-air batteries, a high power density and a large operating voltage are achieved, with a performance comparable to that of the commercial Pt/C catalyst. This work presents a facile strategy for the creation of a new class of energy nanomaterials based on fullerenes, demonstrating their practical uses in electrocatalytic ORR processes and Zn-air batteries.

16.
Chemistry ; 27(40): 10387-10393, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-33899282

RESUMO

Controlled crystallization of fullerene molecules into ordered molecular assemblies is important for their applications. However, the morphology engineering of fullerene[C70 ] assemblies is challenging, and complicated architectures have rarely been reported due to the low molecular symmetry of C70 molecules, which makes their crystallization difficult to control and the low production yield as well. Herein, with the assistance of solvent intercalation, a general reprecipitation approach is reported to prepare morphologically controllable C70 microcrystals with mesitylene as a good solvent and n-propanol as a poor solvent in one solvent system without replacing specific solvents. A series of C70 microcrystals with high uniformity from perfect cubes and defective hoppers to novel cruciform-pillars are obtained by intentionally tuning C70 concentration and the volume ratio of mesitylene to n-propanol. Among them, novel cruciform-pillar-shaped microcrystals are obtained for the first time by further decreasing the amount of mesitylene in the solvent-intercalated microcrystals. Notably, the C70 concentration is a key parameter for the selective growth of C70 hopper, rather than the volume ratio of mesitylene to n-propanol. Interestingly, the hopper-shaped microcrystals exhibit excellent photoluminescence properties relative to those of cubes and cruciform-pillars owing to the enhanced light absorption, proving their potential applications in optoelectronic devices. This study offers new insights into the morphology-controlled synthesis of other micro/nanostructured organic microcrystals and the fine tuning of photoluminescence properties of organic crystals.

17.
Langmuir ; 37(23): 7219-7226, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34078082

RESUMO

In this work, lignin/chitosan nanoparticles (Lig/Chi NPs) with controlled structures were synthesized in a simple and scalable microfluidic system. When the positively charged chitosan and the negatively charged lignin solution were blended in a microreactor, Lig/Chi NPs were rapidly formed via the electrostatic coassembly between the amino groups of chitosan and the carboxyl groups of lignin. The ζ potential changes from negative (-13 mV) to positive (+54.5 mV) for Lig NPs and Lig/Chi NPs, respectively. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results demonstrated that Lig/Chi NPs have an average particle size of about 180 nm, which can be used as nanocarriers for drug delivery. The anticancer drug nanoparticles with docetaxel (DTX) and curcumin (CCM) were prepared by coassembly with Lig/Chi NPs in a microreactor, which had good drug loading efficiency, biocompatibility, and can release drugs in response to pH in the weakly acidic environment of the tumor. The drug release amounts in acidic solutions that simulated the tumor microenvironment were 51% (DTX@Lig/Chi NPs) and 50% (CCM@Lig/Chi NPs), respectively, which were better than the release amounts at pH 7.4, and have an obvious killing effect on HeLa cells.


Assuntos
Antineoplásicos , Quitosana , Nanopartículas , Antineoplásicos/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Lignina , Microfluídica , Tamanho da Partícula
18.
Langmuir ; 37(44): 13067-13074, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34711055

RESUMO

In this article, meso-tetrakis (4-carboxyphenyl) porphyrins modified with different amino acids were designed, synthesized, and researched. The chiral self-assembly behavior of these porphyrin-amino acid molecules can be precisely controlled by adjusting the pH, constituent amino acids, and temperature, thereby giving rise to chiral nanostructures with precisely tailored helical pitch and handedness. This research provides a certain reference for the design and preparation of chiral nanomaterials and has potential application prospects in chiral resolution and chiral catalysis.

19.
Langmuir ; 37(47): 13810-13815, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34788036

RESUMO

Osteoarthritis is a prevalent degenerative joint disease characterized by progressive articular cartilage loss and destruction. The resultant increase in friction causes severe pain. The collagen I matrix (COL I) has been used clinically for cartilage repair; however, how COL I acts at cartilage surfaces is unclear. Here, we studied adsorption and lubrication of synovial fluid components, albumin, γ-globulin, and the phospholipid DPPC, on COL I under physiological conditions using surface plasmon resonance and an in situ sensing surface force apparatus. Our results revealed COL I had poor lubrication ability, a fairly high coefficient of friction (COF, µ = 0.651 ± 0.013), and surface damage under a 7 mN load. DPPC formed an improved lubricating layer on COL I (µ = 0.072 ± 0.016). In sharp contrast, albumin and γ-globulin exhibited poor lubrication with an order of magnitude higher COF but still provided benefits by protecting COL I from wear. Hence, DPPC on COL I may help optimize COL I implantation design.


Assuntos
Cartilagem Articular , Colágeno Tipo I , Fricção , Lipídeos , Lubrificação
20.
Mol Biol Rep ; 48(3): 2223-2233, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33689093

RESUMO

TEOSINTE BRANCHED 1/CYCLOIDEA/PROLIFERATING CELL FACTOR 1 (TCP) transcription factors control multiple aspects of growth and development in various plant species. However, few genes were reported to be directly targeted and regulated by them through their specific binding sites, and then uncover their functions in plants. A consensus DNA-binding site motif of TCP2 was identified by random binding site selection (RBSS). DNA recognized by TCP2 contained the motif G(G/T)GGNCC(A/C), which showed high consistency with motifs bound by other TCP domain proteins. Consequently, this motif was regarded as the specific DNA-binding sites of TCP2. Circadian clock associated 1 (CCA1) and EARLY FLOWERING 3 (ELF3) were subsequently considered as potential target genes owing to the containing of the similar TCP2 binding sites or core binding sites GGNCC and found to be positively regulated by TCP2 via DNA binding. Phenotype analysis results showed that mutation and over-expression of TCP2 resulted in variations in leaf morphogenesis, especially the double or triple mutations of TCP2, 4 and 10. Mutations in TCPs caused late flowering. Finally, TCP2 was shown to influence hypocotyl elongation by mediating the jasmonate signaling pathway. Overall, these results provide a basis for future studies aimed at distinguishing the target genes of TCP2 and elucidating the important roles of TCP2 in plant growth and development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Sítios de Ligação/genética , Sequência Consenso/genética , DNA de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Sequência de Bases , Ciclopentanos/metabolismo , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Hipocótilo/crescimento & desenvolvimento , Morfogênese/genética , Mutação/genética , Oxilipinas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Ligação Proteica , Domínios Proteicos , Transdução de Sinais , Fatores de Tempo , Fatores de Transcrição/química , Fatores de Transcrição/genética
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