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1.
Food Chem ; 368: 130823, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34404005

RESUMO

The current work focuses on the facile and effective synthesis of a new nanocomposite based on multiwalled carbon nanotubes (MWCNT) decorated with magnetic core-shell Fe3O4@SiO2 and functionalized with 3-mercaptopropyltrimethoxysilane (3-MPTS) used in the vortex-assisted dispersive magnetic solid-phase extraction (VA-DMSPE) of Cd(II) ions in environmental and food samples. The nanocomposite was characterized and the parameters that influenced the VA-DMSPE were optimized through a fractional factorial design 25-1. The proposed method provided a preconcentration factor of 33.14 times, detection and quantification limits of 0.090 µg L-1 and 0.302 µg L-1, respectively, and a linearity range of 0.001-40.0 µg L-1. The developed method was effectively applied to preconcentrate and determine Cd(II) in water, tobacco, green tea leaves, ginkgo biloba, carrots, and rice samples, and its accuracy was evaluated using GF AAS.


Assuntos
Nanotubos de Carbono , Plantas Medicinais , Adsorção , Cádmio , Fenômenos Magnéticos , Dióxido de Silício , Extração em Fase Sólida , Compostos de Sulfidrila , Água
2.
J Hazard Mater ; 421: 126756, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34352523

RESUMO

Widespread heavy metal pollution in soils has posed serious threat to vegetable production and food security, yet little is still known about heavy metal accumulation and distribution in the majority of vegetable crops. Here, we report the generation of a tissue atlas of cadmium accumulation in zucchini (Cucurbita pepo var. Giromontial), a globally important cucurbit crop, based on two-season experiment with six genotypes grown under cadmium contaminated soils. Plant growth and development as manifested by biomass, flowering time and plant architecture were unaffected by 10 mg/kg cadmium treatment, but high level of cadmium enrichment was detected in all genotypes. Roots accumulated the largest amount of cadmium, whereas the cadmium concentrations in fruits was also considerable. The exocarps of fruits possessed nearly half of the total cadmium in fruits, rendering it a "hotspot" of safety risk. Measurement of the thiol-containing chelates revealed that concentration of GSH but not PCs was correlated with the cadmium concentration in subdivided fruit tissues, suggesting a mechanism of phloem-specific transportation of cadmium in the form of Cd-GSH. Based on the collective data, a tentative model describing the relationship between long-distance phloem transport and cadmium distribution in sink organs is proposed. The implications for food safety are discussed.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Inocuidade dos Alimentos , Raízes de Plantas/química , Poluentes do Solo/análise , Compostos de Sulfidrila , Verduras
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120282, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34454131

RESUMO

The conversion of p-aminothiophenol (PATP) or p-nitrothiophenol (PNTP) to p,p'-dimercaptoazobenzene (DMAB) has been used as model reactions to study plasmon-catalyzed reaction on nanoparticles. Herein, we report the conversion of PNTP to DMAB which is triggered by SO32- ions on gold nanoparticles (AuNPs) for the first time. With the addition of SO32-, the Raman peaks at 1139, 1392, 1437 cm-1 appears, which indicates the formation of DMAB. The experiment results suggested that the synergistic effect of AuNPs and SO32- promoted the conversion of PNTP to DMAB. Besides, the proposed catalysis system is high selectivity to SO32- ions, which provides a new detection route to SO32- ions in the future. More importantly, the possible reaction mechanism has been put forward which is helpful to understand the surface plasmon-assisted catalytic reduction of PNTP on the surface of SERS substrate.


Assuntos
Ouro , Nanopartículas Metálicas , Catálise , Análise Espectral Raman , Compostos de Sulfidrila , Sulfitos
4.
Food Chem ; 367: 130756, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388633

RESUMO

This study was aimed at evaluating the potential of high-intensity ultrasound (HIU, 450 W for 10 min) combined with hydrogen peroxide (H2O2) having various concentrations (0, 50, 100, 200, 400, 800 µmol/g protein) to inhibit the thermal aggregation behavior of myofibrillar proteins (MPs) in water. The results indicated that the addition of H2O2 interfered with the intermolecular sulfhydryl-disulfide interchange and inhibited the disulfide bond cross-linking. The H2O2-mediated conversion of cysteine to thiol derivatives appeared to be the primary mechanism of this effect. The HIU combined with H2O2, especially at the H2O2 concentration of 200 µmol/g, corresponded to a more significant inhibitory effect than that of only H2O2, which attributed to the dissociation of the filamentous myosin structure that led to an enhanced accessibility of the buried sulfhydryl groups. In conclusion, these findings provide direct evidence for the role of HIU combined with H2O2 in improving the thermal stability of MPs.


Assuntos
Peróxido de Hidrogênio , Água , Concentração de Íons de Hidrogênio , Miosinas , Compostos de Sulfidrila
5.
J Colloid Interface Sci ; 606(Pt 1): 510-517, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34403860

RESUMO

Gold modified thiol graphene (Au@HS-rGO) was prepared and applied as sensing platform for constructing the electrochemical aptasensor. While gold-palladium modified zirconium metal-organic frameworks (AuPd@UiO-67) nanozyme was employed as signal enhancer for detecting mercury ions (Hg2+) sensitively. Herein, gold nanoparticles (Au NPs) were modified on HS-rGO to form the thin Au@HS-rGO layer. Then the substrate strand (Apt1) was modified on the platform through Au-S bond. The signal strand (Apt2) was further decorated on the platform in the presence of Hg2+. Herein, the Apt2 was labeled with AuPd@UiO-67 nanozyme, which exhibited catalase-like properties to catalyze H2O2, thereby generating the electrical signal. With the concentration of Hg2+ increased, the amount of modified Apt2-AuPd@UiO-67 increased, leading to the rise of current response. Since the current responses were linear with concentration of Hg2+, the detection of Hg2+ can be achieved. Under the optimum conditions, the prepared electrochemical aptasensor exhibited wide linear range from 1.0 nmol/L to 1.0 mmol/L, along with a low detection limit of 0.16 nmol/L. Moreover, the electrochemical aptasensor showed excellent selectivity, reproducibility and stability, together with superior performance in actual water sample analysis. Therefore, this proposed electrochemical aptasensor may have promising applications and provide references for environmental monitoring and management.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Mercúrio , Nanopartículas Metálicas , Estruturas Metalorgânicas , Técnicas Eletroquímicas , Ouro , Peróxido de Hidrogênio , Limite de Detecção , Paládio , Reprodutibilidade dos Testes , Compostos de Sulfidrila , Zircônio
6.
Chemosphere ; 286(Pt 1): 131659, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346342

RESUMO

Current study presents a facile synthesis method for thiol functionalised silica microsphere loaded polymeric hydrogel. Silica microspheres were synthesised as core shell particles by sol-gel method followed by hydrolysis and condensation reaction to form the silica core. The silica was functionalised with thiol and the functionalised silica microsphere was subsequently impregnated into polymeric alginate matrix to form thiol functionalised silica microspheres loaded alginate hydrogel beads (SH-SiO2MS-Ca-Alg). The developed components and final products were characterised by BET, FTIR, DLS, SEM-EDS. The developed SH-SiO2MS-Ca-Alg hydrogel beads were used for efficient removal of Pb and Cd [72-97 % for Pb; 60-85 % for Cd at concentration range of 0.1-100 µg mL-1 and optimum pH 5-7] from aquatic medium. The sorption capacities evaluated for Pb and Cd from Langmuir isotherm were 127.99 and 70.68 mgg-1 respectively. Uptake kinetics, isotherm, thermodynamics, intraparticle diffusion studies were carried out for both Pb (II) and Cd (II). Mechanism of Pb (II) and Cd (II) removal by SH-SiO2MS-Ca-Alg hydrogel hybrid beads was proposed with the help of zeta potentials of SH-SiO2MS at different pH along with fraction diagram of Pb and Cd.


Assuntos
Cádmio , Poluentes Químicos da Água , Adsorção , Cádmio/análise , Hidrogéis , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Microesferas , Dióxido de Silício , Compostos de Sulfidrila , Poluentes Químicos da Água/análise
7.
Chemosphere ; 286(Pt 2): 131784, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34371358

RESUMO

Humus is an important parameter to affect the environmental fate of arsenic (As) in tailing soil. According to the batch and column experiment, the effects of humus (HS) including humic acid (HA), fulvic acid (FA) on the As release and basic properties of soil were studied in the soil from a mining region. In addition, HA was modified by 3-mercaptopropyltrimethoxysilane (3-MPTS) with different sulfur content (S%) to improve the release capacity of As. The results indicated that HS could destroy the binding of As with Fe, Mn, Al and Ca without affecting the basic properties of tailings soil, thus achieving the co-release of As and associated metals. Besides, the As release capacity of FA (25.47 %) was slightly higher than that of HA (21.90 %). The ability of thiol-modified HAs to release As from tailings soil after being modified with different S% of 3-MPTS was significantly improved, of which 2 % had the best treatment. The thiol groups (-SH) reached 45.00 % of total S. With the increase of S%, the surface thoil content, aromatization degree and total reduction capacity (TRC) of HA increased. The study demonstrated that HS and thiol-modified HA could promote the migration of As and could advance the treatment of heavy metal contaminated tailing soil.


Assuntos
Arsênio , Poluentes do Solo , Benzopiranos , Substâncias Húmicas/análise , Solo , Poluentes do Solo/análise , Compostos de Sulfidrila
8.
Environ Pollut ; 291: 118221, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740294

RESUMO

Sulfur, an essential macronutrient, plays important roles in plant development and stress mitigation. Sulfur deficiency, a common problem in agricultural soils, may disturb plant stress resistance and xenobiotic detoxification. In the present study, the function and mechanism of limited sulfur nutrition on the residues and phtotoxicity of imidacloprid were investigated in lettuce plants. Sulfur deficiency significantly increased imidacloprid accumulation in lettuce tissues, exacerbated imidacloprid biological toxicity by enhancing the accumulation of toxic metabolites, like imidacloprid-olefin. Simultaneously, imidacloprid-induced detoxification enzymes including cytochromes P450, glutathione S-transferases (GSTs) and glycosyltransferases were inhibited under limited sulfur supply. On the other hand, sulfur deficiency further enhanced the generation of reactive oxygen species and exacerbated lipid peroxidation in lettuce tissues. Sulfur deficiency mainly reduced the abundance of thiol groups, which are essential redox modulators as well as xenobiotic conjugators, and significantly inhibited GSTs expression. These results clearly suggested that sulfur deficiency inhibited the synthesis of sulfur-containing compounds, leading to increased accumulation of pesticide residues and toxic metabolites as well as reduced detoxification capacity, consequently leading to oxidative damage to plants. Therefore, moderate sulfur supply in regions where neonicotinoid insecticides are intensively and indiscriminately used may be an efficient strategy to reduce pesticide residues and the potential risk to ecosystem.


Assuntos
Inseticidas , Plântula , Ecossistema , Inseticidas/toxicidade , Alface , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Compostos de Sulfidrila , Enxofre
9.
Anal Chim Acta ; 1186: 339116, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34756262

RESUMO

The development of a near-infrared fluorophore with excellent fluorescence performance, a large Stokes shift, and good biocompatibility has become a focus in the field of fluorescence imaging in recent years. Based on quantum chemistry calculations and reasonable molecular design strategies, a new NIR fluorophore was developed and characterized by simple synthesis, easy structural modification, and a large Stokes shift (105 nm). Furthermore, two new "activatable" fluorescent probes QN-Cys and QN-DNP were synthesized using a simple structural modification. The probe QN-Cys can recognize Cys with high sensitivity (LOD = 128 nM) and high selectivity, and its fluorescence intensity has a good linear relationship with the Cys concentration in the range of 5-35 µM. Furthermore, probe QN-Cys can effectively distinguish Cys from Hcy and GSH, and was successfully applied to the detection and imaging of Cys in human serum, cells, and zebrafish. The probe QN-DNP showed a good specific and sensitive (LOD = 78 nM) fluorescence response to thiophenol, and its fluorescence intensity has a good linear relationship with the thiophenol concentration in the range of 5-30 µM. Furthermore, it was successfully applied to detect thiophenol in real water samples with good recoveries (97-102%), and image thiophenol in living cells, zebrafish and mice. Notebly, the QN-DNP probe could be applied to visualize the distribution of thiophenol in the mice.


Assuntos
Cisteína , Corantes Fluorescentes , Animais , Células HeLa , Humanos , Camundongos , Imagem Óptica , Fenóis , Compostos de Sulfidrila , Peixe-Zebra
10.
Int J Mol Sci ; 22(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34639127

RESUMO

Toxoplasma gondii is an apicomplexan parasite that infects and proliferates within many different types of host cells and infects virtually all warm-blooded animals and humans. Trypanosoma brucei is an extracellular kinetoplastid that causes human African trypanosomiasis and Nagana disease in cattle, primarily in rural sub-Saharan Africa. Current treatments against both parasites have limitations, e.g., suboptimal efficacy and adverse side effects. Here, we investigate the potential cellular and molecular targets of a trithiolato-bridged arene ruthenium complex conjugated to 9-(2-hydroxyethyl)-adenine (1), which inhibits both parasites with IC50s below 10-7 M. Proteins that bind to 1 were identified using differential affinity chromatography (DAC) followed by shotgun-mass spectrometry. A trithiolato-bridged ruthenium complex decorated with hypoxanthine (2) and 2-hydroxyethyl-adenine (3) were included as controls. Transmission electron microscopy (TEM) revealed distinct ultrastructural modifications in the mitochondrion induced by (1) but not by (2) and (3) in both species. DAC revealed 128 proteins in T. gondii and 46 proteins in T. brucei specifically binding to 1 but not 2 or 3. In T. gondii, the most abundant was a protein with unknown function annotated as YOU2. This protein is a homolog to the human mitochondrial inner membrane translocase subunit Tim10. In T. brucei, the most abundant proteins binding specifically to 1 were mitochondrial ATP-synthase subunits. Exposure of T. brucei bloodstream forms to 1 resulted in rapid breakdown of the ATP-synthase complex. Moreover, both datasets contained proteins involved in key steps of metabolism and nucleic acid binding proteins.


Assuntos
Nucleotídeos/química , Compostos de Rutênio/farmacologia , Compostos de Sulfidrila/química , Toxoplasma/efeitos dos fármacos , Toxoplasmose/tratamento farmacológico , Trypanosoma brucei brucei/efeitos dos fármacos , Tripanossomíase/tratamento farmacológico , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Proteínas de Protozoários/metabolismo , Compostos de Rutênio/química , Toxoplasma/metabolismo , Toxoplasmose/metabolismo , Toxoplasmose/parasitologia , Trypanosoma brucei brucei/metabolismo , Tripanossomíase/metabolismo , Tripanossomíase/parasitologia
11.
J Am Coll Cardiol ; 78(16): 1635-1654, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34649702

RESUMO

Coronavirus disease-2019 (COVID-19) is associated with systemic inflammation, endothelial activation, and multiorgan manifestations. Lipid-modulating agents may be useful in treating patients with COVID-19. These agents may inhibit viral entry by lipid raft disruption or ameliorate the inflammatory response and endothelial activation. In addition, dyslipidemia with lower high-density lipoprotein cholesterol and higher triglyceride levels portend worse outcomes in patients with COVID-19. Upon a systematic search, 40 randomized controlled trials (RCTs) with lipid-modulating agents were identified, including 17 statin trials, 14 omega-3 fatty acids RCTs, 3 fibrate RCTs, 5 niacin RCTs, and 1 dalcetrapib RCT for the management or prevention of COVID-19. From these 40 RCTs, only 2 have reported preliminary results, and most others are ongoing. This paper summarizes the ongoing or completed RCTs of lipid-modulating agents in COVID-19 and the implications of these trials for patient management.


Assuntos
COVID-19/tratamento farmacológico , COVID-19/prevenção & controle , Ácidos Graxos Ômega-3/uso terapêutico , Ácidos Fíbricos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Niacina/uso terapêutico , Amidas/farmacologia , Amidas/uso terapêutico , Ésteres/farmacologia , Ésteres/uso terapêutico , Ácidos Graxos Ômega-3/farmacologia , Ácidos Fíbricos/farmacologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Reguladores do Metabolismo de Lipídeos/farmacologia , Reguladores do Metabolismo de Lipídeos/uso terapêutico , Niacina/farmacologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Compostos de Sulfidrila/farmacologia , Compostos de Sulfidrila/uso terapêutico
12.
J Agric Food Chem ; 69(40): 11919-11925, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34609136

RESUMO

Polyfunctional thiols like 3-sulfanylhexan-1-ol (3SH) and its ester 3-sulfanylhexyl acetate (3SHA) are important aroma determinants in wine with exceptionally low odor thresholds. 3SH is largely found in grape must bound to glutathione and cysteine and requires enzymatic action to be perceived sensorially. The wine yeast Saccharomyces cerevisiae is ineffective in releasing volatile thiols from their precursor configuration. For this purpose, a yeast strain was constructed that expresses the carbon-sulfur lyase encoding the tnaA gene from Escherichia coli and overexpresses its native alcohol acetyltransferase encoding genes, ATF1 and ATF2. The resulting yeast strain, which co-expresses tnaA and ATF1, showed elevated 3SH-releasing capabilities and the esterification of 3SH to its acetate ester 3SHA. Levels of over 7000 ng/L of 3SHA in Sauvignon blanc wines were achieved. Enhanced release and esterification of 3SH were also shown in the fermentation of guava and passionfruit pulp and three hop varieties. This study offers prospects for the development of flavor-enhancing yeast strains with optimized thiol-releasing and esterification capabilities in a diverse set of beverage matrices.


Assuntos
Proteínas de Saccharomyces cerevisiae , Vitis , Vinho , Acetiltransferases , Esterificação , Fermentação , Hexanóis , Odorantes/análise , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Compostos de Sulfidrila , Vinho/análise
13.
Biosensors (Basel) ; 11(10)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34677311

RESUMO

Plasma separation is of high interest for lateral flow tests using whole blood as sample liquids. Here, we built a passive microfluidic device for plasma separation with high performance. This device was made by blood filtration membrane and off-stoichiometry thiol-ene (OSTE) pillar forest. OSTE pillar forest was fabricated by double replica moldings of a laser-cut polymethylmethacrylate (PMMA) mold, which has a uniform microstructure. This device utilized a filtration membrane to separate plasma from whole blood samples and used hydrophilic OSTE pillar forest as the capillary pump to propel the plasma. The device can be used to separate blood plasma with high purity for later use in lateral flow tests. The device can process 45 µL of whole blood in 72 s and achieves a plasma separation yield as high as 60.0%. The protein recovery rate of separated plasma is 85.5%, which is on par with state-of-the-art technologies. This device can be further developed into lateral flow tests for biomarker detection in whole blood.


Assuntos
Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas , Plasma/química , Separação Celular , Desenho de Equipamento , Filtração , Florestas , Compostos de Sulfidrila
14.
Molecules ; 26(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34641524

RESUMO

Photothermal therapy (PTT) is one of the most promising cancer treatment methods because hyperthermal effects and immunogenic cell death via PTT are destructive to cancer. However, PTT requires photoabsorbers that absorb near-infrared (NIR) light with deeper penetration depth in the body and effectively convert light into heat. Gold nanoparticles have various unique properties which are suitable for photoabsorbers, e.g., controllable optical properties and easy surface modification. We developed gold nanodot swarms (AuNSw) by creating small gold nanoparticles (sGNPs) in the presence of hydrophobically-modified glycol chitosan. The sGNPs assembled with each other through their interaction with amine groups of glycol chitosan. AuNSw absorbed 808-nm laser and increased temperature to 55 °C. In contrast, AuNSw lost its particle structure upon exposure to thiolated molecules and did not convert NIR light into heat. In vitro studies demonstrated the photothermal effect and immunogenic cell death after PTT with AuNSW. After intratumoral injection of AuNSw with laser irradiation, tumor growth of xenograft mouse models was depressed. We found hyperthermal damage and immunogenic cell death in tumor tissues through histological and biochemical analyses. Thiol-responsive AuNSw showed feasibility for PTT, with advanced functionality in the tumor microenvironment.


Assuntos
Quitosana/química , Nanopartículas Metálicas/química , Terapia Fototérmica/métodos , Animais , Ouro/química , Humanos , Terapia a Laser , Masculino , Nanopartículas Metálicas/uso terapêutico , Camundongos Endogâmicos BALB C , Neoplasias/terapia , Tamanho da Partícula , Terapia Fototérmica/instrumentação , Compostos de Sulfidrila/química , Temperatura , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Curr Protoc ; 1(9): e262, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34570435

RESUMO

The dynamic and unstable nature of protein nitrosothiols (PSNOs) derived from complex biological matrices (like cell lysates) make them unsuitable for proteomic/biochemical analysis in vitro. In an attempt to increase the stability of cell-derived PSNOs, scientists have devised methods to derivatize thiols undergoing nitrosylation, with a suitable molecule, to yield a stable adduct that could easily be detected using appropriate antibodies. The Biotin Switch Assay (BTSA) is currently the most widely used method for tagging PSNOs; however, the error-prone and cumbersome nature of the BTSA protocol prompted the development of alternative mechanisms of tagging cell-derived PSNOs. One such method is the immuno-spin trapping method using 5,5-dimethyl-1-pyrroline N-oxide (DMPO), which effectively overcomes the shortcomings of the BTSA and proves to be a promising alternative. Here we describe the protocol for DMPO-based PSNO labeling and subsequent proteomic analysis by western blotting with an anti-DMPO antibody. © 2021 Wiley Periodicals LLC. Basic Protocol: Labeling of cell-derived PSNOs by DMPO-based immuno-spin trapping and their subsequent analysis by immunostaining.


Assuntos
Proteínas , Proteômica , Radicais Livres , Detecção de Spin , Compostos de Sulfidrila
18.
Biomacromolecules ; 22(10): 4295-4305, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34533298

RESUMO

Radical polymerization is one of the most widely used methods for the synthesis of polymeric materials for biomedical applications, such as drug delivery, 3D cell culture, and regenerative medicine. Among radical polymerization reactions, thiol-ene click chemistry has shown excellent orthogonality in diverse reaction conditions. However, our preliminary investigations revealed that it fails in cell culture environment. Herein, we investigate the mechanisms by which cell culture media interfere with radical photoreactions. Three different models including free radical linear photopolymerization (N,N-dimethylacrylamide photopolymerization), free radical photohydrogelation (poly(ethylene glycol) diacrylate photohydrogelation), and thiol-ene photohydrogelation (4-arm poly(ethylene glycol)-norbornene thiol-ene photohydrogelation) were investigated. We showed that common cell culture media ingredients can interfere with radical polymerization by two different pathways; namely, radical chain transfer and radical scavenging effects. Thiol-ene photoclick hydrogelation was seriously affected by cell culture media especially under the alkaline conditions of many of them, due to the impact of deprotonation of the thiol reactant. We intend these findings to serve as a reference guide to researchers employing free radical-based molecular synthesis in cell culture settings. The nonbenign impact of media components, pH, and concentration should provide a cue for future studies that aim to prepare well-defined polymeric materials in the presence of cell culture media.


Assuntos
Química Click , Hidrogéis , Técnicas de Cultura de Células , Polimerização , Compostos de Sulfidrila
19.
J Org Chem ; 86(19): 13644-13663, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34516111

RESUMO

By facilitating the chemical conversion of thiols to thiosulfonates, phosphoramidite/phosphite bearing sp3-hybridized carbon serves as an ideal coupling material to forge new connections at room temperature. In this work, a functional group-induced, additive-free, novel, S-P bond-forming approach is presented. This protocol exhibits good functional group tolerance with wide applications that include phosphorylation of cysteine derivatives, development of a one-pot approach to mixed unsymmetrical thiophosphonates, and extension of the concept to different Se-P bonds. Meticulously, our reaction also generated a S-P bond against cyclic 1,2-dithiane-1-dioxide in a byproduct-free manner. These Michaelis-Arbuzov-type reactions are easy to conduct, work efficiently in a reduced reaction time, and are applicable to gram-scale preparation as well.


Assuntos
Compostos de Sulfidrila
20.
Int J Clin Pract ; 75(11): e14838, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34519144

RESUMO

OBJECTIVE: We aimed to investigate the effects of hypotensive anaesthesia on oxidative stress with serum thiol/disulphide balance in patients undergoing elective septoplasty procedures under general anaesthesia. METHODS: Seventy-two patients between the ages of 18-60, with a physical condition I -II, according to the American Society of Anesthesiologists, were included in this prospective observational study. Septoplasty was chosen for standard surgical stress. According to the maintenance of anaesthesia, patients were divided into the groups as Hypotensive Anaesthesia (n = 40) and Normotensive Anaesthesia (n = 32). Serum thiol/disulphide levels were measured by the method developed by Erel & Neselioglu. RESULTS: The native thiol and total thiol values of both groups measured at the 60th min intraoperatively were significantly lower than the preoperative values (both P < .01). Intraoperatively, at the 60th min, there was no significant difference in terms of post-native thiol and post-total thiol levels between hypotensive and normotensive anaesthesia groups (P = .68 and .81, respectively). Age >40 years and female gender were found to have a significant effect on dynamic oxidative stress (P = .002 and .001, respectively). CONCLUSION: This pilot study has found that hypotensive anaesthesia had no adverse effect on dynamic thiol/disulphide balance in elective surgeries.


Assuntos
Anestesia , Dissulfetos , Adolescente , Adulto , Feminino , Homeostase , Humanos , Pessoa de Meia-Idade , Estresse Oxidativo , Projetos Piloto , Compostos de Sulfidrila , Adulto Jovem
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