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1.
Environ Technol ; : 1-26, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37961915

RESUMO

In this work, a new type of composite nanoparticles, 'pearl chain', was developed by linking titanium dioxide and silicon dioxide by polyacrylic acid polymer chains, and the prepared TiO2-PAA-SiO2 composite nanoparticles were analysed by SEM, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy and thermogravimetric analysis, zeta potential, x-ray diffraction, etc. The success of this work was verified by the successful linking of TiO2-PAA-SiO2 composite nanoparticles.TiO2-PAA-SiO2 composite nanoparticles were analysed to verify the successful attachment of pearl chains. The obtained TiO2-PAA-SiO2 were subsequently blended in different ratios to prepare polyvinylidene fluoride (PVDF) ultrafiltration membranes. The membrane performance was tested by porosity and water contact angle measurements, scanning electron microscopy, as well as experiments using bovine serum proteins and MTBE interception. The results showed that when a certain amount of TiO2-PAA-SiO2 was added, the surface wettability, porosity and permeability of the prepared modified composite membranes were significantly improved, and the BSA adsorption rate was increased from 71.59% to 80.86%, and the retention rate of MTBE was increased by 77%, in addition to showing a better anti-pollution effect (FRR: 91.07%). It was finally concluded that the prepared membranes embedded with 1.0 wt.% TiO2-PAA-SiO2 nanofillers showed good overall filtration performance, better contamination resistance and remarkable durability. The present work successfully demonstrated the feasibility of using polyacrylic acid chemical chains to connect nanoparticles with different functions to prevent particle loss and substantially enhance membrane performance, which is valuable for bridging connection of composite nanoparticles and exploring the development of high-performance ultrafiltration membranes.

2.
Molecules ; 28(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37764240

RESUMO

A composite film that features bismuth-antimony alloy nanoparticles uniformly embedded in a 3D hierarchical porous carbon skeleton is synthesized by the polyacrylonitrile-spreading method. The dissolved polystyrene is used as a soft template. The average diameter of the bismuth-antimony alloy nanoparticles is ~34.5 nm. The content of the Bi-Sb alloy has an impact on the electrochemical performance of the composite film. When the content of the bismuth-antimony alloy is 45.27%, the reversible capacity and cycling stability of the composite film are the best. Importantly, the composite film outperforms the bismuth-antimony alloy nanoparticles embedded in dense carbon film and the cube carbon nanobox in terms of specific capacity, cycling stability, and rate capability. The composite film can provide a discharge capacity of 322 mAh g-1 after 500 cycles at 0.5 A g-1, 292 mAh g-1 after 500 cycles at 1 A g-1, and 185 mAh g-1 after 2000 cycles at 10 A g-1. The carbon film prepared by the spreading method presents a unique integrated composite structure that significantly improves the structural stability and electronic conductivity of Bi-Sb alloy nanoparticles. The 3D hierarchical porous carbon skeleton structure further enhances electrolyte accessibility, promotes Na+ transport, increases reaction kinetics, and buffers internal stress.

3.
J Cell Mol Med ; 27(21): 3296-3312, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37551845

RESUMO

Finding effective treatments for cancer requires a thorough understanding of how it develops and progresses. Recent research has revealed the crucial role that Zinc and ring finger 2 (ZNRF2) play in the progression of non-small cell lung cancer (NSCLC) by controlling cell growth and death. However, a comprehensive analysis of ZNRF2's role in cancer as a whole has yet to be conducted. Our study sought to investigate the impact of ZNRF2 on diverse human tumours, as well as the molecular pathways involved, using databases such as TCGA (The Cancer Genome Atlas), GEO (Gene Expression Omnibus) and the Human Protein Atlas (HPA), as well as several bioinformatic tools. Our findings indicate that ZNRF2 is generally expressed at higher levels in tumours than in normal tissues, and in some cancers, its levels correlate positively with disease stage, potentially predicting a poor prognosis for patients. We also discovered genetic changes in ZNRF2 among cancer patients, as well as its relationship with cancer-related fibroblasts, endothelial cells and immune cell infiltration. Additionally, we explored potential molecular mechanisms of ZNRF2 in tumours, finding that it increases in hepatocellular carcinoma (HCC) tissues and that inhibiting its expression through ZNRF2 siRNA can limit HepG2 cell proliferation. Overall, our study provides a comprehensive overview of ZNRF2's oncogenic roles across various cancers.


Assuntos
Carcinoma Hepatocelular , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Hepatocelular/genética , Zinco , Células Endoteliais/patologia , Neoplasias Pulmonares/genética , Neoplasias Hepáticas/genética , Ubiquitina-Proteína Ligases/genética
4.
Structure ; 31(4): 424-434.e6, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36863339

RESUMO

Ca2+-dependent activator proteins for secretion (CAPSs) are required for Ca2+-regulated exocytosis in neurons and neuroendocrine cells. CAPSs contain a pleckstrin homology (PH) domain that binds PI(4,5)P2-membrane. There is also a C2 domain residing adjacent to the PH domain, but its function remains unclear. In this study, we solved the crystal structure of the CAPS-1 C2PH module. The structure showed that the C2 and PH tandem packs against one another mainly via hydrophobic residues. With this interaction, the C2PH module exhibited enhanced binding to PI(4,5)P2-membrane compared with the isolated PH domain. In addition, we identified a new PI(4,5)P2-binding site on the C2 domain. Disruption of either the tight interaction between the C2 and PH domains or the PI(4,5)P2-binding sites on both domains significantly impairs CAPS-1 function in Ca2+-regulated exocytosis at the Caenorhabditis elegans neuromuscular junction (NMJ). These results suggest that the C2 and PH domains constitute an effective unit to promote Ca2+-regulated exocytosis.


Assuntos
Proteínas de Ligação ao Cálcio , Domínios de Homologia à Plecstrina , Animais , Proteínas de Ligação ao Cálcio/química , Exocitose , Domínios Proteicos , Sítios de Ligação , Caenorhabditis elegans/metabolismo
5.
Br J Pharmacol ; 180(14): 1878-1896, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36727262

RESUMO

BACKGROUND AND PURPOSE: Repeated amino acid sequences in proteins are widely found, and the glycine-serine-alanine repeat is an element with a general propensity to form ß-sheet aggregates as found in key pathological factors, in several neurodegenerative diseases. Such properties of this repeat may guide development of disease-modifying therapies for neurodegenerative disease. However, details of its role and underlying mechanism(s) remain largely unknown. EXPERIMENTAL APPROACH: Actions of specific glycine-serine-alanine repeat peptides (SNPs), especially SNP-9, on Alzheimer's disease (AD)-like abnormalities were evaluated in transgenic mice and Caenorhabditis elegans, and in rat and cell models. Entry of SNPs into the brain, SNP activity in neuronal cells and peptide entry into cells were analysed in vivo and in vitro. Cell-free systems and the yeast two-hybrid system were also used to explore possible targets of SNP-9, and interactions of potential targets with SNP-9 were confirmed in cell-based systems. KEY RESULTS: We first identified SNP-9 as a potent neuroprotective peptide with the activity to decrease oligomeric amyloid ß (Aß) via co-assembling with the toxic Aß oligomer to form hetero-oligomers. Also, calcyclin-binding protein was found to act as a SNP-9-binding protein, by screening of a human brain cDNA library. Such binding showed that SNP-9 could regulate the abnormal hyperphosphorylation of tau via calcyclin-binding protein. CONCLUSION AND IMPLICATIONS: Our study provides a foundation for development of SNPs, especially SNP-9, as potential therapeutic interventions for AD. We propose SNP-9 as a potential therapeutic agent for the treatment of AD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Camundongos , Ratos , Animais , Humanos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Serina , Proteína A6 Ligante de Cálcio S100 , Camundongos Transgênicos , Caenorhabditis elegans/metabolismo
6.
PLoS Genet ; 18(10): e1010211, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36279278

RESUMO

Changes in neurotransmitter receptor abundance at post-synaptic elements play a pivotal role in regulating synaptic strength. For this reason, there is significant interest in identifying and characterizing the scaffolds required for receptor localization at different synapses. Here we analyze the role of two C. elegans post-synaptic scaffolding proteins (LIN-2/CASK and FRM-3/FARP) at cholinergic neuromuscular junctions. Constitutive knockouts or muscle specific inactivation of lin-2 and frm-3 dramatically reduced spontaneous and evoked post-synaptic currents. These synaptic defects resulted from the decreased abundance of two classes of post-synaptic ionotropic acetylcholine receptors (ACR-16/CHRNA7 and levamisole-activated AChRs). LIN-2's AChR scaffolding function is mediated by its SH3 and PDZ domains, which interact with AChRs and FRM-3/FARP, respectively. Thus, our findings show that post-synaptic LIN-2/FRM-3 complexes promote cholinergic synaptic transmission by recruiting AChRs to post-synaptic elements.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Junção Neuromuscular/metabolismo , Receptores Colinérgicos/genética , Receptores Colinérgicos/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Transmissão Sináptica/genética , Colinérgicos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Helminto/metabolismo
7.
J Mater Chem B ; 10(37): 7473-7490, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-35993266

RESUMO

3D printing technology, otherwise known as additive manufacturing, has provided a promising tool for manufacturing customized biomaterials for tissue engineering and regenerative medicine applications. A vast variety of biomaterials including metals, ceramics, polymers, and composites are currently being used as base materials in 3D printing. In recent years, nanomaterials have been incorporated into 3D printing polymers to fabricate innovative, versatile, multifunctional hybrid materials that can be used in many different applications within the biomedical field. This review focuses on recent advances in novel hybrid biomaterials composed of nanomaterials and 3D printing technologies for biomedical applications. Various nanomaterials including metal-based nanomaterials, metal-organic frameworks, upconversion nanoparticles, and lipid-based nanoparticles used for 3D printing are presented, with a summary of the mechanisms, functional properties, advantages, disadvantages, and applications in biomedical 3D printing. To finish, this review offers a perspective and discusses the challenges facing the further development of nanomaterials in biomedical 3D printing.


Assuntos
Estruturas Metalorgânicas , Nanoestruturas , Materiais Biocompatíveis , Lipídeos , Polímeros , Impressão Tridimensional
8.
PLoS One ; 17(5): e0268952, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35622869

RESUMO

Data-nulling superimposed pilot (DNSP) effectively alleviates the superimposed interference of superimposed training (ST)-based channel estimation (CE) in orthogonal frequency division multiplexing (OFDM) systems, while facing the challenges of the estimation accuracy and computational complexity. By developing the promising solutions of deep learning (DL) in the physical layer of wireless communication, we fuse the DNSP and DL to tackle these challenges in this paper. Nevertheless, due to the changes of wireless scenarios, the model mismatch of DL leads to the performance degradation of CE, and thus faces the issue of network retraining. To address this issue, a lightweight transfer learning (TL) network is further proposed for the DL-based DNSP scheme, and thus structures a TL-based CE in OFDM systems. Specifically, based on the linear receiver, the least squares estimation is first employed to extract the initial features of CE. With the extracted features, we develop a convolutional neural network (CNN) to fuse the solutions of DL-based CE and the CE of DNSP. Finally, a lightweight TL network is constructed to address the model mismatch. To this end, a novel CE network for the DNSP scheme in OFDM systems is structured, which improves its estimation accuracy and alleviates the model mismatch. The experimental results show that in all signal-to-noise-ratio (SNR) regions, the proposed method achieves lower normalized mean squared error (NMSE) than the existing DNSP schemes with minimum mean square error (MMSE)-based CE. For example, when the SNR is 0 decibel (dB), the proposed scheme achieves similar NMSE as that of the MMSE-based CE scheme at 20 dB, thereby significantly improving the estimation accuracy of CE. In addition, relative to the existing schemes, the improvement of the proposed scheme presents its robustness against the impacts of parameter variations.


Assuntos
Algoritmos , Pilotos , Comunicação , Humanos , Análise dos Mínimos Quadrados , Aprendizado de Máquina
9.
PLoS One ; 17(3): e0265109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35271663

RESUMO

In frequency-division duplexing (FDD) massive multiple-input multiple-output (MIMO) systems, 1-bit compressed sensing (CS)-based superimposed channel state information (CSI) feedback has shown many advantages, while still faces many challenges, such as low accuracy of the downlink CSI recovery and large processing delays. To overcome these drawbacks, this paper proposes a deep learning (DL) scheme to improve the 1-bit compressed sensing-based superimposed CSI feedback. On the user side, the downlink CSI is compressed with the 1-bit CS technique, superimposed on the uplink user data sequences (UL-US), and then sent back to the base station (BS). At the BS, based on the model-driven approach and assisted by the superimposition-interference cancellation technology, a multi-task detection network is first constructed for detecting both the UL-US and downlink CSI. In particular, this detection network is jointly trained to detect the UL-US and downlink CSI simultaneously, capturing a globally optimized network parameter. Then, with the recovered bits for the downlink CSI, a lightweight reconstruction scheme, which consists of an initial feature extraction of the downlink CSI with the simplified traditional method and a single hidden layer network, is utilized to reconstruct the downlink CSI with low processing delay. Compared with the 1-bit CS-based superimposed CSI feedback scheme, the proposed scheme improves the recovery accuracy of the UL-US and downlink CSI with lower processing delay and possesses robustness against parameter variations.


Assuntos
Aprendizado Profundo , Retroalimentação , Tecnologia
10.
Int J Mol Sci ; 22(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34576206

RESUMO

Actinobacillus pleuropneumoniae is a pathogen that infects pigs and poses a serious threat to the pig industry. The emergence of quinolone-resistant strains of A.pleuropneumoniae further limits the choice of treatment. However, the mechanisms behind quinolone resistance in A.pleuropneumoniae remain unclear. The genomes of a ciprofloxacin-resistant strain, A. pleuropneumoniae SC1810 and its isogenic drug-sensitive counterpart were sequenced and analyzed using various bioinformatics tools, revealing 559 differentially expressed genes. The biological membrane, plasmid-mediated quinolone resistance genes and quinolone resistance-determining region were detected. Upregulated expression of efflux pump genes led to ciprofloxacin resistance. The expression of two porins, OmpP2B and LamB, was significantly downregulated in the mutant. Three nonsynonymous mutations in the mutant strain disrupted the water-metal ion bridge, subsequently reducing the affinity of the quinolone-enzyme complex for metal ions and leading to cross-resistance to multiple quinolones. The mechanism of quinolone resistance in A. pleuropneumoniae may involve inhibition of expression of the outer membrane protein genes ompP2B and lamB to decrease drug influx, overexpression of AcrB in the efflux pump to enhance its drug-pumping ability, and mutation in the quinolone resistance-determining region to weaken the binding of the remaining drugs. These findings will provide new potential targets for treatment.


Assuntos
Quinolonas/farmacologia , Actinobacillus pleuropneumoniae/efeitos dos fármacos , Actinobacillus pleuropneumoniae/genética , Biofilmes/efeitos dos fármacos , Porinas/metabolismo , Transcriptoma/genética
11.
Environ Toxicol Chem ; 33(5): 1135-41, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24477927

RESUMO

Fullerene (C(60)), with its unique physical properties and nanometer size, has been mass-produced for many applications in recent decades. The increased likelihood of direct release into the environment has raised interest in understanding both the environmental fate and corresponding biological effects of fullerenes to living organisms. Because few studies have emphasized fullerene uptake and resulting biochemical responses by living organisms, a toxicity screening test and a 28-d bioaccumulation test for Lumbriculus variegatus were performed. No mortality was observed in the range of 0.05 mg C(60) /kg dry sediment to 11.33 mg C(60) /kg dry sediment. A biota-sediment accumulation factor of micron-sized fullerene agglomerates (µ-C(60)) was 0.032 ± 0.008 at day 28, which is relatively low compared with pyrene (1.62 ± 0.22). Catalase (CAT) activity, an oxidative stress indicator, was elevated significantly on day 14 for L. variegatus exposed to µ-C(60) (p = 0.034). This peak CAT activity corresponded to the highest body residues observed in the present study, 199 ± 80 µg C(60) /kg dry weight sediment. Additionally, smaller C(60) agglomerate size increased bioaccumulation potential in L. variegatus. The relationship between C(60) body residue and the increased CAT activity followed a linear regression. All results suggest that C(60) has a lower bioaccumulation potential than pyrene but a higher potential to induce oxidative stress in L. variegatus.


Assuntos
Catalase/metabolismo , Poluentes Ambientais/farmacocinética , Fulerenos/farmacocinética , Oligoquetos/metabolismo , Animais , Poluentes Ambientais/análise , Poluentes Ambientais/química , Poluentes Ambientais/toxicidade , Fulerenos/análise , Fulerenos/química , Fulerenos/toxicidade , Sedimentos Geológicos/química , Oligoquetos/efeitos dos fármacos , Oligoquetos/enzimologia , Pirenos/análise , Pirenos/farmacocinética
12.
Sci Total Environ ; 442: 56-62, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23178764

RESUMO

Nanotechnology is one of the most promising technologies to emerge in recent decades. Materials that are specially engineered to have at least one dimension that is no larger than 100 nm are now continuously manufactured and incorporated as critical components of different products that people use daily. While we are taking advantage of nanomaterials (NMs) and nano-products, they may pose a risk to humans and the broader environment. Some types of fibrous NMs such as carbon nanotubes and nano-fibers may present a risk similar to that of asbestos. Some carbon or metal based NMs may threaten the environment due to their bioaccumulative nature within food webs. In order to prevent future adverse effects from products or byproducts of nanotechnology, we suggest an integrated multi-faceted approach which includes an integrated regulation that is based upon life cycle assessment, empirically derived risk assessment. Advanced research that fills the knowledge gap regarding the understanding of NMs in scientific and social norms will be helpful in a full life cycle assessment of NMs. Emphasizing nanotechnology education to the public for an increased understanding and participation associated with media coverage will finally draw governments' attention with an integrated legislation to be instituted. Developing the optimal mix of these tools, including research, public education, media coverage, integrated legislation, will be significant to proactively manage the complexity of nanotechnology and prevent any undesirable effect due to the NMs exposure.


Assuntos
Saúde Ambiental/legislação & jurisprudência , Regulamentação Governamental , Nanoestruturas , Nanotecnologia/legislação & jurisprudência , Participação da Comunidade/legislação & jurisprudência , Ecotoxicologia/legislação & jurisprudência , Ecotoxicologia/organização & administração , Nanoestruturas/normas , Nanoestruturas/toxicidade , Política Pública , Medição de Risco , Estados Unidos
13.
Environ Toxicol Chem ; 31(3): 550-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22180293

RESUMO

Pharmaceuticals and personal care products (PPCPs) have emerged as a group of potential environmental contaminants of concern. The occurrence of gemfibrozil, a lipid-regulating drug, was studied in the influent and effluent at a wastewater treatment plant (WWTP) and groundwater below a land application site receiving treated effluent from the WWTP. In addition, the sorption of gemfibrozil in two loam soils and sand was assessed, and biological degradation rates in two soil types under aerobic conditions were also determined. Results showed that concentrations of gemfibrozil in wastewater influent, effluent, and groundwater were in the range of 3.47 to 63.8 µg/L, 0.08 to 19.4 µg/L, and undetectable to 6.86 µg/L, respectively. Data also indicated that gemfibrozil in the wastewater could reach groundwater following land application of the treated effluent. Soil-water distribution coefficients for gemfibrozil, determined by the batch equilibrium method, varied with organic carbon content in the soils. The sorption capacity was silt loam > sandy loam > sand. Under aerobic conditions, dissipation half-lives for gemfibrozil in sandy loam and silt loam soils were 17.8 and 20.6 days, respectively; 25.4 and 11.3% of gemfibrozil was lost through biodegradation from the two soils over 14 days.


Assuntos
Genfibrozila/análise , Água Subterrânea/química , Hipolipemiantes/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Monitoramento Ambiental , Solo/química , Eliminação de Resíduos Líquidos
14.
Talanta ; 87: 35-9, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22099645

RESUMO

In this new century, nanotechnology has evolved from a novel concept to an integral aspect of product advancement. With an increasing presence of nanomaterials in commercial products, more concern about the impact of nanomaterials on human health and also the environment has been considered and evaluated. Fullerenes (C60), have been studied in several different areas and applied widely. Wider application of fullerenes into different products in the recent decades has increased the potential of fullerene releases into the environment. Fullerene research involves physical and chemical characteristics, toxicity, environment fate, and interaction with other pollutions. However, few studies have addressed fullerene quantification in solid matrices. Standardized artificial sediment was prepared following OECD guideline 225, and extracted C60 was quantified by HPLC-UV. A normal shaking method was employed for extraction for two times. Extracts were concentrated and analyzed. Recovery results revealed up to 90.7 ± 4.5%, 90.0 ± 3.8%, 93.8 ± 5.4%, respectively for 1.62, 0.65, and 0.32 µg/g C60 in dry sediment, which shows no significant difference between different concentration levels. Furthermore, extraction efficiency did not show significant difference while using Telfon(TM) tubes (96.5 ± 6.0%) or silanized glass vessels (90.7 ± 4.5%). This indicated that relative low cost is required for the method to be initially started in any lab. This technique has also been applied in the determination of C60 in sediment samples collected after a 10 day benthic exposure study. Extraction precision has been increased from 4.5% (S.D.) as the validation value up to 15.4% (RSD%) or more. The increased inhomogeneity by bioturbation and matrix complexity of the sediment after the toxicity test could both lower the extraction precision.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Monitoramento Ambiental/métodos , Fulerenos/isolamento & purificação , Sedimentos Geológicos/análise , Cromatografia Líquida de Alta Pressão/economia , Monitoramento Ambiental/economia , Sensibilidade e Especificidade
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