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1.
Food Chem ; 462: 140947, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208736

RESUMO

Excess nitrites are potentially threatening to human health, so it is urgent to develop accurate and sensitive methods. The development of sensors can provide early warning of possible hazards and alert people to protect public health. This work presents an NiSx@MoS2-composite with excellent electrochemical activity, representing a key finding for highly sensitive NO2- detection and sensor development. With the assistance of NiSx@MoS2, this electrochemical sensor has excellent quantitative detection performance. It has a wide detection range (0.0001-0.0020 mg/mL) and a low detection limit (1.863*10-5 mg/mL) for NO2-. This electrochemical sensor maintains excellent specificity among numerous interferences, and it completes the accurate detection of different real food samples. Pleasingly, the electrochemical sensor has satisfactory repeatability stability, and potential for practical applications. It would demonstrate tremendous potential in scientific dietary guidance, food safety detection and other fields.


Assuntos
Dissulfetos , Técnicas Eletroquímicas , Limite de Detecção , Molibdênio , Molibdênio/química , Técnicas Eletroquímicas/instrumentação , Dissulfetos/química , Nitritos/análise , Contaminação de Alimentos/análise
2.
Cells ; 13(17)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39273052

RESUMO

The complex structure of monoclonal antibodies (mAbs) expressed in Chinese hamster ovary (CHO) cells may result in the accumulation of unfolded proteins, triggering endoplasmic reticulum (ER) stress and an unfolded protein response (UPR). If the protein folding ability cannot maintain ER homeostasis, the cell will shut down protein translation and ultimately induce apoptosis. We co-overexpressed HsQSOX1b and survivin proteins in the antibody-producing cell line CHO-PAb to obtain a new cell line, CHO-PAb-QS. Compared with CHO-PAb cells, the survival time of CHO-PAb-QS cells in batch culture was extended by 2 days, and the antibody accumulation and productivity were increased by 52% and 45%, respectively. The proportion of (HC-LC)2 was approximately doubled in the CHO-PAb-QS cells, which adapted to the accelerated disulfide bond folding capacity by upregulating the UPR's strength and increasing the ER content. The results of the apoptosis assays indicated that the CHO-PAb-QS cell line exhibited more excellent resistance to apoptosis induced by ER stress. Finally, CHO-PAb-QS cells exhibited mild oxidative stress but did not significantly alter the redox status. This study demonstrated that strategies based on HsQSOX1b and survivin co-overexpression could facilitate protein disulfide bond folding and anti-apoptosis ability, enhancing antibody production efficiency in CHO cell lines.


Assuntos
Apoptose , Cricetulus , Dissulfetos , Dobramento de Proteína , Células CHO , Animais , Dissulfetos/metabolismo , Dissulfetos/química , Estresse do Retículo Endoplasmático , Resposta a Proteínas não Dobradas , Formação de Anticorpos , Anticorpos Monoclonais , Cricetinae , Survivina/metabolismo , Humanos , Retículo Endoplasmático/metabolismo , Estresse Oxidativo
3.
Molecules ; 29(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39275071

RESUMO

Oligonucleotide drugs are shining in clinical therapeutics, but efficient and safe delivery systems severely limit their widespread use. A disulfide unit technology platform based on dynamic thiol exchange chemistry at the cell membrane has the potential for drug delivery. However, the alteration of the disulfide unit CSSC dihedral angle induced by different substituents directly affects the effectiveness of this technology and its stability. Previously, we constructed a trivalent low dihedral angle disulfide unit that can effectively promote the cellular uptake of small molecules. Here, we constructed a novel disulfide unit-masked oligonucleotide hybrid based on a low dihedral angle disulfide unit, motivated by prodrug design. Cellular imaging results showed that such a system exhibited superior cellular delivery efficiency than the commercial Lipo2000 without cytotoxicity. The thiol reagents significantly reduced its cellular uptake (57-74%), which proved to be endocytosis-independent. In addition, in vivo distribution experiments in mice showed that such systems can be rapidly distributed in liver tissues with a duration of action of more than 24 h, representing a potential means of silencing genes involved in the pathogenesis of liver-like diseases. In conclusion, this trivalent disulfide unit-masked system we constructed can effectively deliver large oligonucleotide drugs.


Assuntos
Dissulfetos , Oligonucleotídeos , Dissulfetos/química , Animais , Oligonucleotídeos/química , Camundongos , Humanos , Sistemas de Liberação de Medicamentos , Fígado/metabolismo , Fígado/efeitos dos fármacos
4.
Nutrients ; 16(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39275211

RESUMO

Hypertension is a major risk factor for heart disease and stroke. Garlic has a long history of use in traditional medicine for various conditions, including hypertension. This narrative review examined the scientific evidence on the efficacy of garlic in lowering blood pressure. It explores the historical uses of garlic in different cultures for medicinal purposes and delves into the phytochemical composition of garlic, highlighting key components, like allicin and ajoene, that are believed to contribute to its potential health benefits. Clinical studies that investigated the effects of garlic and garlic-based supplements on blood pressure are presented, with the findings suggesting that garlic consumption may modestly reduce blood pressure, particularly in individuals with mild hypertension. Potential mechanisms of action include increased nitric oxide production, improved endothelial function, and antioxidant properties. While garlic may offer some benefits for blood pressure management, it should not be considered a substitute for conventional antihypertensive medications. Further large-scale, long-term clinical trials are warranted to establish the efficacy of garlic in managing hypertension, including the optimal dosage and formulation.


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Alho , Hipertensão , Alho/química , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/prevenção & controle , Pressão Sanguínea/efeitos dos fármacos , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Dissulfetos/farmacologia , Ácidos Sulfínicos/farmacologia , Suplementos Nutricionais , Fitoterapia , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Sulfóxidos
5.
Luminescence ; 39(9): e4884, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39258707

RESUMO

In present work, synthesis of a nanohybrid material using Fe and MoS2 has been performed via a cost-effective and environmentally friendly route for sustainable manufacturing innovation. Rice straw extract was prepared and used as a reducing and chelating agent to synthesize the nanohybrid material by mixing it with molybdenum disulfide (MoS2) and ferric nitrate [Fe (NO3)3.9H2O], followed by heating and calcination. The X-ray diffraction (XRD) pattern confirms the formation of a nanohybrid consisting of monoclinic Fe2(MoO4)3, cubic Fe2.957O4, and orthorhombic FeS with 86% consisting of Fe2(MoO4)3. The properties were analyzed through Fourier-transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the dynamic light scattering (DLS) study revealed a heterogeneous size distribution, with an average particle size of 48.42 nm for 18% of particles and 384.54 nm for 82% of particles. Additionally, the zeta potential was measured to be -18.88 mV, suggesting moderate stability. X-ray photoelectron spectroscopy (XPS) results confirmed the presence of both Fe2+ and Fe3+ oxidation states along with the presence of Molybdenum (Mo), oxygen (O), and Sulphur (S). The prepared nanohybrid material exhibited a band gap of 2.95 eV, and the photoluminescence intensity increased almost twice that of bare MoS2. The present work holds potential applications in photo luminescent nanoplatform for biomedical applications.


Assuntos
Dissulfetos , Química Verde , Molibdênio , Oryza , Tamanho da Partícula , Molibdênio/química , Dissulfetos/química , Oryza/química , Ferro/química , Propriedades de Superfície
6.
Anal Chim Acta ; 1325: 343090, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39244300

RESUMO

BACKGROUND: Curcumin has been used in traditional medicine because of its pharmacological activity, including antioxidant, antibacterial, anticancer, and anticarcinogenic properties. Therefore, sensitive and selective monitoring of curcumin is highly demand for practical application. RESULTS: In this study, we describe the construction of a fluorescence method for curcumin assay based on nitrogen-doped MoS2 quantum dots (N-MoS2 QDs). The N-MoS2 QDs are constructed by a solvothermal method using sodium molybdate and Cys as precursors. With the addition of curcumin, the bright blue fluorescence of N-MoS2 QDs is quenched by the inner filter effect (IFE). The QDs emitted bright blue fluorescence and could be quenched by the addition of curcumin via IFE. The dynamic range is the range of 0.1-10 µM for curcumin detection, with a detection limit of 59 nM. N-MoS2 QDs were applied for curcumin assay in real samples with good recovery. In addition, the N-MoS2 QDs exhibited relative low cytotoxicity and could be applied for fluorescence-based imaging in biological samples. SIGNIFICANCE: Our study indicates that the sensor possesses good selectivity to monitor curcumin in water samples, human urine samples, ginger powder samples, mustard samples, and curry samples with satisfactory recoveries. The N-MoS2 QDs possess less cytotoxicity with excellent biocompatibility and were applied for in vitro cell imaging.


Assuntos
Curcumina , Dissulfetos , Corantes Fluorescentes , Molibdênio , Nitrogênio , Pontos Quânticos , Curcumina/química , Curcumina/farmacologia , Pontos Quânticos/química , Molibdênio/química , Humanos , Dissulfetos/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Nitrogênio/química , Imagem Óptica , Limite de Detecção , Espectrometria de Fluorescência , Sobrevivência Celular/efeitos dos fármacos
7.
Nat Commun ; 15(1): 7799, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39242578

RESUMO

Peptides are valuable for therapeutic development, with multicyclic peptides showing promise in mimicking antigen-binding potency of antibodies. However, our capability to engineer multicyclic peptide scaffolds, particularly for the construction of large combinatorial libraries, is still limited. Here, we study the interplay of disulfide pairing between three biscysteine motifs, and designed a range of triscysteine motifs with unique disulfide-directing capability for regulating the oxidative folding of multicyclic peptides. We demonstrate that incorporating these motifs into random sequences allows the design of disulfide-directed multicyclic peptide (DDMP) libraries with up to four disulfide bonds, which have been applied for the successful discovery of peptide binders with nanomolar affinity to several challenging targets. This study encourages the use of more diverse disulfide-directing motifs for creating multicyclic peptide libraries and opens an avenue for discovering functional peptides in sequence and structural space beyond existing peptide scaffolds, potentially advancing the field of peptide drug discovery.


Assuntos
Cisteína , Dissulfetos , Biblioteca de Peptídeos , Dissulfetos/química , Cisteína/química , Motivos de Aminoácidos , Descoberta de Drogas/métodos , Sequência de Aminoácidos , Peptídeos/química , Peptídeos/metabolismo , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Ligação Proteica , Humanos , Oxirredução , Dobramento de Proteína
8.
Nat Commun ; 15(1): 8136, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289340

RESUMO

Diminished mitochondrial function underlies many rare inborn errors of energy metabolism and contributes to more common age-associated metabolic and neurodegenerative disorders. Thus, boosting mitochondrial biogenesis has been proposed as a potential therapeutic approach for these diseases; however, currently we have a limited arsenal of compounds that can stimulate mitochondrial function. In this study, we designed molybdenum disulfide (MoS2) nanoflowers with predefined atomic vacancies that are fabricated by self-assembly of individual two-dimensional MoS2 nanosheets. Treatment of mammalian cells with MoS2 nanoflowers increased mitochondrial biogenesis by induction of PGC-1α and TFAM, which resulted in increased mitochondrial DNA copy number, enhanced expression of nuclear and mitochondrial-DNA encoded genes, and increased levels of mitochondrial respiratory chain proteins. Consistent with increased mitochondrial biogenesis, treatment with MoS2 nanoflowers enhanced mitochondrial respiratory capacity and adenosine triphosphate production in multiple mammalian cell types. Taken together, this study reveals that predefined atomic vacancies in MoS2 nanoflowers stimulate mitochondrial function by upregulating the expression of genes required for mitochondrial biogenesis.


Assuntos
Dissulfetos , Mitocôndrias , Molibdênio , Nanopartículas , Molibdênio/farmacologia , Molibdênio/química , Molibdênio/metabolismo , Dissulfetos/química , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Humanos , Nanopartículas/química , Biogênese de Organelas , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Animais , Trifosfato de Adenosina/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Camundongos
9.
J Agric Food Chem ; 72(37): 20658-20669, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39226125

RESUMO

Sulfur-containing compounds have diverse biological functions and are crucial in crop protection chemistry. In this study, a series of novel 1-methyl-1H-pyrazol-5-amine derivatives incorporating disulfide moieties were synthesized and evaluated for their antimicrobial properties. In vitro bioassays demonstrated that compound 7f displayed potent antifungal activity against Valsa mali, with an EC50 value of 0.64 mg/L, outperforming allicin (EC50 = 26.0 mg/L) but lower than tebuconazole (EC50 = 0.33 mg/L). In vivo experiments confirmed that compound 7f could effectively inhibit V. mali infection on apples at a concentration of 100 mg/L, similar to the positive control tebuconazole. Mechanistic studies revealed that compound 7f could induce hyphal shrinkage and collapse, trigger intracellular reactive oxygen species accumulation, modulate antioxidant enzyme activities, initiate lipid peroxidation, and ultimately cause irreversible oxidative damage to the cells of V. mali. Additionally, compound 7b exhibited notable antibacterial activity, particularly against Pseudomonas syringae pv. actinidiae, with a MIC90 value of 1.56 mg/L, surpassing the positive controls allicin, bismerthiazol, and streptomycin sulfate. These findings suggest that 1-methyl-1H-pyrazol-5-amine derivatives containing disulfide moieties hold promise as potent candidates for the development of novel antimicrobial agents.


Assuntos
Dissulfetos , Testes de Sensibilidade Microbiana , Pirazóis , Dissulfetos/química , Dissulfetos/farmacologia , Pirazóis/farmacologia , Pirazóis/química , Pirazóis/síntese química , Doenças das Plantas/microbiologia , Relação Estrutura-Atividade , Pseudomonas syringae/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/síntese química , Estrutura Molecular , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química
10.
J Agric Food Chem ; 72(37): 20299-20307, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39231265

RESUMO

Microorganisms are the most common cause of food spoilage. Pseudomonas aeruginosa is a common foodborne pathogen that causes food spoilage and poses a serious threat to food safety. As a crucial target in antitoxicity strategies, the quorum sensing (QS) system shows promising potential for further development. The garlic extract diallyl disulfide exhibits inhibitory activity against the QS system of P. aeruginosa, with disulfide bonds serving as the active component. However, the biological activity of other symmetric disulfides has not been investigated in this capacity. The study synthesized 39 disulfide bond-containing analogs and evaluated their activity as quorum sensing inhibitors (QSIs). The results showed that p-hydroxyphenyl substitution can replace the allyl groups while maintaining strong biological activity. The virulence factors production was reduced by compound 2i, with the strongest inhibitory effect being observed on elastase production. Synergistic inhibition was observed in the presence of antibiotics like ciprofloxacin and tobramycin. 2i successfully inhibited P. aeruginosa infection in the Galleria mellonella larvae model. Primary mechanism studies using transcriptome, surface plasmon resonance and molecular docking suggested that 2i inhibits the QS system by targeting the LasR protein. Thus, compound 2i could be used in developing QSIs for the control of P. aeruginosa infections.


Assuntos
Antibacterianos , Dissulfetos , Alho , Extratos Vegetais , Pseudomonas aeruginosa , Percepção de Quorum , Percepção de Quorum/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Alho/química , Dissulfetos/química , Dissulfetos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Mariposas/efeitos dos fármacos , Mariposas/microbiologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia
11.
PLoS One ; 19(9): e0310166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39255261

RESUMO

This study demonstrates the use of computational methods to simulate the molecular dynamics involved in hemoglobin concentration sensing, utilizing Material Studio and the TCAD Silvaco device simulator. A non-invasive and flexible Graphene/MoS2 heterostructure has been proposed for sensing hemoglobin concentration in blood samples. The findings reveal a notable shift in the wavelength-dependent refractive index and extinction coefficient, as well as significant changes in the absorption coefficient and reflectivity of the Graphene/MoS2 heterostructure in response to different hemoglobin concentrations, specifically within an approximate range of 0.3 µm to 1 µm. Moreover, the spectral response of the heterostructure demonstrates that at a particular wavelength of approximately 600 nm, a maximum response is obtained. This wavelength can be considered optimal for detecting various levels of hemoglobin using this heterostructure. The anticipated outcome is a comprehensive understanding of the fundamental principles, ultimately resulting in the development of an exceptionally sensitive platform for detecting hemoglobin concentration.


Assuntos
Dissulfetos , Grafite , Hemoglobinas , Molibdênio , Grafite/química , Hemoglobinas/análise , Hemoglobinas/química , Molibdênio/química , Humanos , Dissulfetos/química , Dissulfetos/sangue , Simulação de Dinâmica Molecular , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação
12.
Int J Pharm ; 664: 124600, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39159858

RESUMO

Acute lung injury (ALI) arises from an excessive inflammatory response, usually progressing to acute respiratory distress syndrome (ARDS) if not promptly addressed. There is currently a limited array of effective treatments available for ALI. In this study, we developed disulfide bond-bridged prodrug self-assembled nanoparticles (referred to as DSSS NPs). These nanoparticles were consisted of Dexamethasone (Dex) and stearic acid (SA), and were designed to target and treat ALI. DSSS NPs demonstrated a substantial drug loading capacity with 37.75 % of Dex, which is much higher than conventional nanomedicines (usually < 10 %). Moreover, they exhibited the potential to specifically target injured lung tissue and inflammatory microenvironment-responsive release drugs. Consequently, DSSS NPs reduced significantly the levels of pro-inflammatory cytokines and tissue damage in mice with ALI induced by lipopolysaccharide (LPS). Overall, DSSS NPs offer a promising strategy for treatment of acute lung injury.


Assuntos
Lesão Pulmonar Aguda , Anti-Inflamatórios , Dexametasona , Dissulfetos , Lipopolissacarídeos , Nanopartículas , Oxirredução , Ácidos Esteáricos , Dexametasona/administração & dosagem , Dexametasona/química , Lesão Pulmonar Aguda/tratamento farmacológico , Animais , Nanopartículas/química , Dissulfetos/química , Camundongos , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Ácidos Esteáricos/química , Masculino , Liberação Controlada de Fármacos , Citocinas/metabolismo , Pró-Fármacos/química , Pró-Fármacos/administração & dosagem , Humanos , Camundongos Endogâmicos C57BL , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Portadores de Fármacos/química
13.
Colloids Surf B Biointerfaces ; 244: 114164, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39180990

RESUMO

Trimethylamine N-oxide (TMAO) is a gut metabolite produced by dietary L-carnitine and choline metabolism. Its altered level in the serum has been implicated in human health and diseases such as colorectal cancer, chronic kidney diseases, cardiovascular diseases, etc. Early detection of TMAO in body fluids has been presumed to be significant in understanding the pathogenesis and treatment of many diseases. Hence, developing reliable and rapid technologies for its detection may augment our understanding of pathogenesis and diagnosis of diseases. Hence, in the present work, polypyrrole (Ppy)@molybdenum(III)sulfide (Mo2S3) nanosheets (NS) composite molecularly imprinted polymer (MIP) (Ppy@Mo2S3-MIP) based electrochemical sensor has been fabricated for the detection of TMAO. Polypyrrole (Ppy) and Mo2S3 NS have been synthesized by chemical oxidative polymerization and hydrothermal techniques, respectively. The synthesized nanocomposite has been validated using different techniques such as X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The fabricated Ppy@Mo2S3-MIP sensor showed a linear detection range from 30 µM to 210 µM, a sensitivity of 1.21 µA µM-1 cm-2 and a limit of detection as 1.4 µM for the detection of TMAO and found more robust and improved when compared with Ppy-MIP using identical parameters. The fabricated sensor is also highly selective towards TMAO. It can be further used to detect TMAO in human samples such as urine quickly.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Metilaminas , Molibdênio , Polímeros , Pirróis , Polímeros/química , Pirróis/química , Molibdênio/química , Técnicas Eletroquímicas/métodos , Metilaminas/química , Metilaminas/análise , Humanos , Impressão Molecular , Sulfetos/química , Limite de Detecção , Nanoestruturas/química , Propriedades de Superfície , Tamanho da Partícula , Dissulfetos
14.
Mikrochim Acta ; 191(9): 555, 2024 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172272

RESUMO

A novel signal amplification strategy was developed by combining near-infrared light with MoS2/CuO/Au nanocomposite for building a colorimetric immunoassay. First, MoS2/CuO/Au nanocomposite was synthesized by precipitation and photoreduction methods and characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). MoS2/CuO/Au nanocomposite has oxidase-like activity and can oxidize TMB to form a blue product (TMBox). Further, the catalytic oxidation of TMB was accelerated under near-infrared (NIR) laser radiation. The sandwich-type colorimetric immunoassay was constructed using MoS2/CuO/Au nanocomposite. Under the enhancement of near-infrared light, carcinoembryonic antigen (CEA) was sensitively detected in the range 0.1 to 40 ng/mL with the limit of detection of 0.03 ng/mL. Moreover, the immunosensor has excellent selectivity and anti-interference, good repeatability, and stability.


Assuntos
Biomarcadores Tumorais , Antígeno Carcinoembrionário , Colorimetria , Cobre , Dissulfetos , Ouro , Raios Infravermelhos , Limite de Detecção , Molibdênio , Nanocompostos , Molibdênio/química , Nanocompostos/química , Cobre/química , Dissulfetos/química , Colorimetria/métodos , Ouro/química , Humanos , Antígeno Carcinoembrionário/sangue , Antígeno Carcinoembrionário/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/análise , Imunoensaio/métodos , Técnicas Biossensoriais/métodos , Anticorpos Imobilizados/imunologia
15.
Environ Res ; 261: 119759, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39122163

RESUMO

Fabrication of ternary composited photocatalytic nanomaterials with strong interaction is vital to deriving the fast charge separation for efficient photodegradation of organic contaminants in wastewater under visible light. In this work, novel ternary 2D/3D/2D MoS2-In2O3-WS2 multi-nanostructures were synthesized using facile hydrothermal processes. XRD, FTIR, and XPS results confirmed the phase, functional groups, and element composition of pure MoS2, MoS2-In2O3, and MoS2-In2O3-WS2 hybrids. UV-DRS spectra of the MoS2-In2O3-WS2 ternary hybrid indicate maximum absorption in the visible light range with a band-gap energy value of 2.4 eV. The surface of the 2D WS2 nanosheet structure tightly blends and densely disperses 2D MoS2 nanosheets and 3D In2O3 nanocubes. This confirmed the formation of the MoS2-In2O3-WS2 ternary hybrid in the form of 2D/3D/2D multi-nanostructures, which is also indicated from SEM and HR-TEM images. The synthesized MoS2-In2O3-WS2 ternary hybrid showed maximum photocatalytic activity under visible-light for antimicrobial agents such as triclosan (TCS) and trichlorocarban (TCC). The photocatalytic activity of TCS was revealed to be 95% at 90 min, while that of TCC was 93% at 100 min. The reusability and stability tests of the prepared MoS2-In2O3-WS2 ternary hybrid after four consecutive photocatalytic cycles were analyzed by FTIR and SEM, which indicated that the prepared ternary hybrid was very stable. Overall results suggested that the developed MoS2-In2O3-WS2 (2D/3D/2D) multi-nanostructures are environmentally friendly and low-cost nanocomposites as a potential photocatalyst for the removal of antimicrobial agents from wastewater.


Assuntos
Dissulfetos , Luz , Molibdênio , Nanocompostos , Fotólise , Molibdênio/química , Nanocompostos/química , Dissulfetos/química , Catálise , Anti-Infecciosos/química , Sulfetos/química , Poluentes Químicos da Água/química , Águas Residuárias/química
16.
J Mater Chem B ; 12(35): 8662-8671, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39110475

RESUMO

Two dimensional (2D) nanosheets of MoS2 were succesfully produced by an exfoliation process in aqueous media with the support from peptides and sonication. The exfoliation process assisted by uncapped MoSBP1 peptides was found to have enhanced efficiency in comparison to the capped counterpart. MoS2 nanosheets obtained using uncapped MoSBP1 have thinner structures containing one layer of MoS2, while in capped version of peptides, MoS2 nanosheets tend to form multilayer (up to 4) structures of exfoliated sheets. Molecular dynamics simulations indicate that inter-sheet gaps generated by sonication in MoS2 nanostacks cannot be maintained by water only; the gaps closed after ∼11 ns. Both capped CMoSBP1 and uncapped MoSBP1 were seen to spontaneously insert into the gap in nanostacks of MoS2 and they can ultimately maintain the inter-sheet gap for longer (≥20 ns). Potential of mean force profiles for the association of two MoS2 nanosheets decorated with CMoSBP1 and MoSBP1 versions of peptides revealed that uncapped MoSBP1 peptides provide good protection from MoS2 nanosheet re-unification. Such protection can prevent the nanosheets from reassociation and subsequent aggregation, whereas the capped CMoSBP1 peptides can offer protection, but over a shorter range. These simulation results could explain the experimental observation of greater efficiency of exfoliation in uncapped MoSBP1 peptides.


Assuntos
Dissulfetos , Simulação de Dinâmica Molecular , Molibdênio , Água , Molibdênio/química , Dissulfetos/química , Água/química , Nanoestruturas/química , Peptídeos/química
17.
Org Biomol Chem ; 22(35): 7180-7186, 2024 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-39157954

RESUMO

The in vitro oxidative folding of the protein bovine pancreatic trypsin inhibitor (BPTI) with oxidized dithiothreitol or glutathione has served as a paradigm for protein folding but could take weeks at physiological pH because of the need to escape from kinetic traps via a rearrangement type pathway. The two major kinetic traps are called N' and N* and contain two of the three native disulfide bonds, which occur between residues 5 and 55, 30 and 51, and 14 and 38. N' is missing the disulfide bond between residues 5 and 55 while N* is missing the disulfide bond between residues 30 and 51. By determining rate constant for the reactions of the kinetic traps N* and N' and their mixed disulfides with glutathione and glutathione disulfide, many for the first time, we demonstrate that growth type pathways are feasible and could even be more efficient than rearrangement type pathways. Thus, formally unproductive pathways became productive. Interestingly, under physiological redox conditions both rearrangement and growth type pathways are important highlighting the redundancy of oxidative protein folding. With the new set of rate constants, modeling indicated that in vitro oxidative protein folding of BPTI via a growth type pathway using an oxidation, reduction and oxidation cycle would significantly improve protein folding efficiency, albeit under non-physiological redox conditions. With these changing conditions 91 ± 2% of native BPTI was achieved in 12 h compared to 83% native protein in 24 h using our previous best conditions of 5 mM GSSG and 5 mM GSH. Therefore, changing redox conditions via an oxidation, reduction and oxidation cycle may become an additional methodology for enhancing in vitro protein folding in aqueous solution.


Assuntos
Aprotinina , Oxirredução , Dobramento de Proteína , Bovinos , Aprotinina/química , Aprotinina/metabolismo , Animais , Cinética , Glutationa/química , Glutationa/metabolismo , Dissulfetos/química
18.
Talanta ; 279: 126675, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39116726

RESUMO

In this study, we developed a wearable nanozyme-enzyme electrochemical biosensor that enablies sweat lactate monitoring. The biosensor comprises a flexible electrode system prepared on a polyimide (PI) film and the Janus textile for unidirectional sweat transport. We obtained favorable electrochemical activities for hydrogen peroxide reduction by modifying the laser-scribed graphene (LSG) electrode with cerium dioxide (CeO2)-molybdenum disulphide (MoS2) nanozyme and gold nanoparticles (AuNPs). By further immobilisation of lactate oxidase (LOx), the proposed biosensor achieves chronoamperometric lactate detection in artificial sweat within a range of 0.1-50.0 mM, a high sensitivity of 25.58 µA mM-1cm-2 and a limit of detection (LoD) down to 0.135 mM, which fully meets the requirements of clinical diagnostics. We demonstrated accurate lactate measurements in spiked artificial sweat, which is consistent with standard ELISA results. To monitor the sweat produced by volunteers while exercising, we conducted on-body tests, showcasing the wearable biosensor's ability to provide clinical sweat lactate diagnosis for medical treatment and sports management.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Grafite , Ácido Láctico , Oxigenases de Função Mista , Suor , Dispositivos Eletrônicos Vestíveis , Técnicas Biossensoriais/instrumentação , Suor/química , Humanos , Ácido Láctico/análise , Técnicas Eletroquímicas/instrumentação , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Ouro/química , Grafite/química , Enzimas Imobilizadas/química , Molibdênio/química , Nanopartículas Metálicas/química , Eletrodos , Dissulfetos/química , Limite de Detecção
19.
Front Immunol ; 15: 1406929, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114655

RESUMO

Numerous enveloped viruses, such as coronaviruses, influenza, and respiratory syncytial virus (RSV), utilize class I fusion proteins for cell entry. During this process, the proteins transition from a prefusion to a postfusion state, undergoing substantial and irreversible conformational changes. The prefusion conformation has repeatedly shown significant potential in vaccine development. However, the instability of this state poses challenges for its practical application in vaccines. While non-native disulfides have been effective in maintaining the prefusion structure, identifying stabilizing disulfide bonds remains an intricate task. Here, we present a general computational approach to systematically identify prefusion-stabilizing disulfides. Our method assesses the geometric constraints of disulfide bonds and introduces a ranking system to estimate their potential in stabilizing the prefusion conformation. We hypothesized that disulfides restricting the initial stages of the conformational switch could offer higher stability to the prefusion state than those preventing unfolding at a later stage. The implementation of our algorithm on the RSV F protein led to the discovery of prefusion-stabilizing disulfides that supported our hypothesis. Furthermore, the evaluation of our top design as a vaccine candidate in a cotton rat model demonstrated robust protection against RSV infection, highlighting the potential of our approach for vaccine development.


Assuntos
Dissulfetos , Proteínas Virais de Fusão , Dissulfetos/química , Animais , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/química , Humanos , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/virologia , Estabilidade Proteica , Desenho Assistido por Computador , Conformação Proteica , Vírus Sinciciais Respiratórios/imunologia , Vacinas contra Vírus Sincicial Respiratório/imunologia , Ratos , Modelos Moleculares
20.
ACS Chem Biol ; 19(9): 2081-2086, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39192734

RESUMO

We report the development of Tether-seq, a transcriptome-wide screen to probe RNA-small molecule interactions using disulfide tethering. This technique uses s4U metabolic labeling to provide sites for reversible and covalent attachment of small molecule disulfides to the transcriptome. By screening under reducing conditions, we identify interactions that are stabilized by binding over those driven by the reactivity of the RNA sites. When applied to cellular RNA, Tether-seq with a disulfide analogue of risdiplam, an FDA-approved drug that targets RNA to treat spinal muscular atrophy (SMA), revealed a number of potential binding sites, most prominently at a site within the cytochrome C oxidase 1 (COX1) transcript. Structure probing by SHAPE-MaP revealed a structured motif and confirmed binding to the lead molecule. This work demonstrates that these screens have the power to identify binding sites throughout the transcriptome and provide invaluable insight into the thermodynamic properties that define small molecule binding.


Assuntos
Dissulfetos , Transcriptoma , Sítios de Ligação , Dissulfetos/química , Humanos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , RNA/metabolismo , RNA/química , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/química
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