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1.
Curr Microbiol ; 79(2): 42, 2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-34982257

RESUMEN

Cysteine and homocysteine suppress the growth of Escherichia coli. It was explained by the inhibition of threonine deaminase (TD) (Harris in J Bacteriol 145(2):1031-1035, 1981). TD inhibition was detected by a decline in its product, 2-ketobutyrate (2-KB). We propose that cysteine or homocysteine may not inhibit TD activity. Instead, 2-KB binds to them forming stable cyclic adducts. This binding possibly leads to isoleucine limitation and growth inhibition.


Asunto(s)
Aminoácidos/farmacología , Escherichia coli , Compuestos de Sulfhidrilo/farmacología , Treonina Deshidratasa , Escherichia coli/enzimología , Treonina Deshidratasa/antagonistas & inhibidores
2.
Chemosphere ; 286(Pt 1): 131659, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34346342

RESUMEN

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.


Asunto(s)
Cadmio , Contaminantes Químicos del Agua , Adsorción , Cadmio/análisis , Hidrogeles , Concentración de Iones de Hidrógeno , Cinética , Plomo , Microesferas , Dióxido de Silicio , Compuestos de Sulfhidrilo , Contaminantes Químicos del Agua/análisis
3.
J Hazard Mater ; 421: 126756, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34352523

RESUMEN

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.


Asunto(s)
Cadmio , Contaminantes del Suelo , Cadmio/análisis , Inocuidad de los Alimentos , Raíces de Plantas/química , Contaminantes del Suelo/análisis , Compuestos de Sulfhidrilo , Verduras
4.
Chemosphere ; 286(Pt 2): 131784, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34371358

RESUMEN

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.


Asunto(s)
Arsénico , Contaminantes del Suelo , Benzopiranos , Sustancias Húmicas/análisis , Suelo , Contaminantes del Suelo/análisis , Compuestos de Sulfhidrilo
5.
Food Chem ; 367: 130756, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34388633

RESUMEN

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.


Asunto(s)
Peróxido de Hidrógeno , Agua , Concentración de Iones de Hidrógeno , Miosinas , Compuestos de Sulfhidrilo
6.
J Colloid Interface Sci ; 606(Pt 1): 510-517, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34403860

RESUMEN

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.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Grafito , Mercurio , Nanopartículas del Metal , Estructuras Metalorgánicas , Técnicas Electroquímicas , Oro , Peróxido de Hidrógeno , Límite de Detección , Paladio , Reproducibilidad de los Resultados , Compuestos de Sulfhidrilo , Circonio
7.
Food Chem ; 368: 130823, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34404005

RESUMEN

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.


Asunto(s)
Nanotubos de Carbono , Plantas Medicinales , Adsorción , Cadmio , Fenómenos Magnéticos , Dióxido de Silicio , Extracción en Fase Sólida , Compuestos de Sulfhidrilo , Agua
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120282, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34454131

RESUMEN

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.


Asunto(s)
Oro , Nanopartículas del Metal , Catálisis , Espectrometría Raman , Compuestos de Sulfhidrilo , Sulfitos
9.
J Hazard Mater ; 424(Pt A): 127388, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34879578

RESUMEN

Mercuric Hg(II) ion forms exceptionally strong complexes with various organic ligands, particularly thiols and dissolved organic matter (DOM) in natural water. Few studies, however, have experimentally determined whether or not the presence of base cations and transition metal ions, such as Ca(II), Cu(II), and Zn(II), would compete with Hg(II) bound to these ligands, as concentrations of these metal ions are usually orders of magnitude higher than Hg(II) in aquatic systems. Different from previous model predictions, a significant fraction of Hg(II) bound to cysteine (CYS), glutathione (GSH), or DOM was found to be competitively exchanged by Cu(II), but not by Zn(II) or Ca(II). About 20-75% of CYS-bound-Hg(II) [at 2:1 CYS:Hg(II)] and 14-40% of GSH-bound-Hg(II) [at 1:1 GSH:Hg(II)] were exchanged by Cu(II) at concentrations 1-3 orders of magnitude greater than Hg(II). Competitive exchange was also observed between Cu(II) and Hg(II) bound to DOM, albeit to a lower extent, depending on relative abundances of thiol and carboxylate functional groups on DOM and their equilibrium time with Hg(II). When complexed with ethylenediaminetetraacetate (EDTA), most Hg(II) could be exchanged by Cu(II) and Zn(II), as well as Ca(II) at increasing concentrations. These results shed additional light on competitive exchange reactions between Hg(II) and coexisting metal ions and have important implications in Hg(II) chemical speciation and biogeochemical transformation, particularly in contaminated environments containing relatively high concentrations of Hg(II) and metal ions.


Asunto(s)
Mercurio , Compuestos de Sulfhidrilo , Cationes , Zinc
10.
Sci Total Environ ; 806(Pt 1): 150510, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34844321

RESUMEN

The preparation of low-cost and highly efficient functional materials for the cleanup of mercury-contaminated water by adsorption in an environmentally friendly way is of great significance. In this study, thiol-functionalized montmorillonite (BSH-MMT) was prepared by a novel one-step mechanochemical grafting method and applied to aqueous Hg2+ and CH3Hg+ adsorption. Characterization results showed that thiol groups were successfully grafted by chemical bonding with Si-OH or broken SiO bonds. The maximum adsorption capacities of BSH-MMT for Hg2+ and CH3Hg+ were 104.79 mg g-1 and 39.27 mg g-1, which were approximately seven- and nine-fold that of pristine MMT, respectively. Adsorption kinetics and isotherm fitting indicated that Hg2+ adsorbs heterogeneously, while CH3Hg+ proceeds through monolayer adsorption, both with chemical adsorption as the rate-limiting step. BSH-MMT maintained high adsorption performance over a wide pH range and in the presence of humic acid because of the high affinity of thiol groups toward mercury. The primary adsorption mechanism of thiol-ligand complexation was confirmed by the results of X-ray photoelectron spectroscopy and X-ray absorption spectra, in which a complex structure of bis-coordinated S-Hg-S (2.30 Å distance) was observed. These results demonstrated that mechanochemical grafting is a promising one-step method to prepare thiol-functionalized montmorillonite for effective cleanup of Hg2+/CH3Hg+ contamination in water.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Adsorción , Bentonita , Concentración de Iones de Hidrógeno , Cinética , Mercurio/análisis , Compuestos de Sulfhidrilo , Contaminantes Químicos del Agua/análisis
11.
J Colloid Interface Sci ; 611: 255-264, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34953458

RESUMEN

Carbon dots (CDs) have been widely used in recent years because of their excellent water solubility and abundant surface functional groups. However, compared with quantum dots or biological probes, the quantum yield of CDs is lower, and the fluorescence mainly concentrated in the blue-green range, which significantly limits the biological applications of CDs. Heteroatoms doping is the most common method to improve the luminescence of CDs. In this work, nitrogen and sulfur co-doped luminescent CDs were successfully synthesized by microwave assisted method using glutathione (GSH) and p-phenylenediamine (PPD) as raw materials. It can emit bright green fluorescence in ethanol solution, and the maximum emission wavelength is 535 nm when excited at 374 nm, and the absolute quantum yield is as high as 63%. Iron ion (Fe3+) can interact with the functional groups on the surface of the CDs to form CDs/Fe3+, which is a non-fluorescence complex, and Fe3+ can be reduced to ferrous ion (Fe2+). In other words, the reaction mechanism of CDs and Fe3+ is a combination of dynamic quenching and static quenching. The fluorescence of CDs quenched by Fe3+ can be restored by thiol, because there is a stronger binding force between sulfhydryl (-SH) on the surface of thiol and Fe3+, which enables CDs to be released. In addition, the CDs has good biocompatibility and stability, indicating that it has excellent potential in bioimaging. This discovery will expand the application of CDs in the fields of biosensing and imaging.


Asunto(s)
Carbono , Puntos Cuánticos , Colorantes Fluorescentes , Hierro , Nitrógeno , Compuestos de Sulfhidrilo , Azufre
12.
Anal Biochem ; 637: 114475, 2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-34813770

RESUMEN

In this study, we developed a novel colorimetric chemosensor for selective and sensitive recognition of Glutathione (GSH) using a simple binary mixture of commercially accessible and inexpensive metal receptors with names, Bromo Pyrogallol Red (BPR) and Xylenol Orange (XO). This procedure is based on the synergistic coordination of BPR and XO with cerium ion (Ce3+) for the recognition of GSH over other available competitive amino acids (AAs) especially thiol species in aqueous media. Generally, cysteine (Cys) and homocysteine (hCys) can seriously interfere with the detection of GSH among common biological species because they possess similar chemical behavior. Using all the information from 1HNMR and FT-IR studies, the proposed interaction is presented in which GSH acts as a tri-dentate ligand with three N donor atoms in conjunction with BPR and XO as mono and bi-dentate ligands respectively. This approach opens a path for selective detection of other AAs by argumentatively selecting the ensemble of mixed organic ligands from commercially available reagents, thereby eliminating the need for developing synthetic receptors, sample preparation, organic solvent mixtures, and expensive equipment. Evaluating the feasibility of the existing method was led to the determination of GSH in human plasma samples.


Asunto(s)
Cerio/química , Colorimetría/métodos , Colorantes/química , Glutatión/sangre , Fenoles/química , Pirogalol/análogos & derivados , Sulfóxidos/química , Técnicas Biosensibles/métodos , Cisteína/análisis , Cisteína/química , Humanos , Indicadores y Reactivos/química , Ligandos , Espectroscopía de Resonancia Magnética/métodos , Pirogalol/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Compuestos de Sulfhidrilo/análisis , Compuestos de Sulfhidrilo/química , Agua/química
13.
Biomolecules ; 11(12)2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34944518

RESUMEN

The deodorant activity of black cumin (Nigella sativa L.) seed, a spice used to flavor curry and vegetable foods in Southwest Asia, against garlic (Allium sativum L.) organosulfur compounds related to human malodor was evaluated. Black cumin seed essential oil showed remarkable deodorant activity against garlic essential oil. The mode of action of this deodorant activity was presumed to be that black cumin seed essential oil covalently reacted with the organosulfur compounds in garlic. Therefore, thymoquinone, which is a major constituent in black cumin seed essential oil, and allyl mercaptan, which is one of the organosulfur compounds produced by cutting garlic, were reacted in vitro, and the products were purified and elucidated using spectroscopic data. As a result, these substances were identified as different allyl mercaptan adducts to dihydrothymoquinone. This chemical reaction was presumed to play a key role in the deodorant activity of black cumin seed essential oil.


Asunto(s)
Benzoquinonas/farmacología , Desodorantes/farmacología , Ajo/química , Nigella sativa/química , Benzoquinonas/química , Cromatografía de Gases y Espectrometría de Masas , Humanos , Concentración de Iones de Hidrógeno , Aceites Volátiles/química , Aceites Volátiles/farmacología , Aceites Vegetales/química , Aceites Vegetales/farmacología , Semillas/química , Compuestos de Sulfhidrilo/química
14.
Clin Lab ; 67(12)2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34910435

RESUMEN

BACKGROUND: The trio Essential Thrombocytosis (ET), Polycythemia Vera (PV), and Primary Myelofibrosis (PM) are BCR-ABL negative myeloproliferative neoplasms. All three diseases have the risk of transforming into acute leukemia. Oxidative stress and some genetic mutations increase the risk of leukemic transformation. The median age in patients with ET, PV, and MF is around 64 years, and it is expected to exceed 65 in the coming years. Since oxidative stress increases with age, we aimed to evaluate the oxidative stress parameters in older patients with myeloproliferative neoplasms. METHODS: The study included a total of 160 patients (57 patients with Essential Thrombocytosis, 52 patients with Primary Myelofibrosis, and 51 patients with Polycythemia Vera) and 56 healthy controls, aged 65 and over. Ischemia Modified Albumin (IMA) and thiol parameters (native thiol, total thiol, and disulfide) were studied from serum samples taken at the time of diagnosis. RESULTS: The median age of the patients was 69 (65 - 85) years. Patients had higher levels of IMA and lower levels of thiol compared to the control group (p < 0.001). When evaluated according to disease subgroups, it was observed that the highest IMA levels and the lowest thiol levels were in patients with PM (p < 0.001). Higher IMA levels and lower native thiol levels were found in patients with the ASXL1 mutation (p < 0.001). CONCLUSIONS: Serum IMA and thiol levels are also significantly changed in older patients with BCR-ABL negative myeloproliferative neoplasia. Changes in these markers are independent of age. Disease-associated mutations such as ASXL1 can also affect the serum levels of these markers.


Asunto(s)
Leucemia Mieloide Aguda , Policitemia Vera , Anciano , Anciano de 80 o más Años , Biomarcadores , Disulfuros , Humanos , Persona de Mediana Edad , Policitemia Vera/diagnóstico , Policitemia Vera/genética , Albúmina Sérica , Compuestos de Sulfhidrilo
15.
Clin Lab ; 67(12)2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34910441

RESUMEN

BACKGROUND: The aim of this study is to investigate the correlation between serum meteorin-like protein levels and thiol/disulfide balance in patients with COVID-19. METHODS: This is a prospective case-control study including 52 PCR-confirmed COVID-19 patients (group 1) and 34 controls (group 2). The present study included patients aged 18 and older who were admitted to the emergency department with symptoms of COVID-19. Meteorin-like protein levels were analyzed using the YL Biont ELISA Kits protocol. Thiol/disulfide balance was studied using the spectrophotometric method. RESULTS: There were 35 males and 17 females in group 1, and 20 males and 14 females in group 2. The groups were similar in terms of gender and age (p > 0.05 and p > 0.05, respectively). Meteorin-like protein was significantly lower in group 1 (p < 0.001). There was no difference between the two groups in terms of total thiol level (p > 0.05). Disulfide, disulfide/native thiol ratio, and disulfide/total thiol ratio were significantly higher in group 1 (p < 0.001, p < 0.001, and p < 0.001, respectively). Native thiol was higher in group 2 (p = 0.002). Native thiol/total thiol ratio was significantly higher in group 2 (p < 0.001). Disulfide, SS/SH%, SS/TT%, and SH/TT% parameters had remarkably high sensitivity (98.1% for them all) and specificity (85.3% for disulfide and 100% for SS/SH%, SS/TT%, and SH/TT%) in differentiating patients and healthy subjects. CONCLUSIONS: In this study, thiol/disulfide balance, which is an indicator of oxidative stress, was disturbed in the disulfide direction and meteorin-like protein was significantly lower in patients with COVID-19. Thiol/disulfide balance and metrnl may play a role in the pathogenesis of COVID-19.


Asunto(s)
COVID-19 , Compuestos de Sulfhidrilo , Biomarcadores , Estudios de Casos y Controles , Femenino , Homeostasis , Humanos , Masculino , Estrés Oxidativo , SARS-CoV-2
16.
Zhonghua Nan Ke Xue ; 27(7): 603-608, 2021 Jul.
Artículo en Chino | MEDLINE | ID: mdl-34914226

RESUMEN

Objective: To establish a method of reversed-phase ultra-performance liquid chromatography with fluorescence (UPLC-FL) detection for simultaneous determination of homocysteine (Hcy), cysteine (Cys), cysteine glycine (CysGly) and glutathione (GSH) and analysis of the contents of the four thiols in the seminal plasma of normal men and patients with hyperuricemia (HUA). METHODS: Seminal plasma samples were collected from 30 normal sperm donors and 30 HUA patients and reduced with tris (2-carboxyethyl) phosphine hydrochloride. Then, the samples were subjected to protein precipitation with trichloroacetic acid solution, derivative reaction with 7-fluorobenzofuran-4-sulfate and isolation with a C18 column, with 0.025 mol/L KH2PO4 (pH 3.0) for mobile phase A and pure methanol for B, followed by equal gradient elution with an excitation wavelength of 380 nm and an emission wavelength of 510 nm. RESULTS: The correlation coefficients (R2) of the four thiols all exceeded 0.999, with an average recovery rate of 94.23-107.87%. Compared with the normal sperm donors, the HUA patients showed significantly increased contents of Cys (ï¼»108.01 ± 48.03ï¼½ vs ï¼»250.10 ± 55.87ï¼½ µmol/L, P < 0.05), Hcy (ï¼»113.97 ± 6.32ï¼½ vs ï¼»48.35 ± 15.07ï¼½ µmol/L, P < 0.05), and GSH (ï¼»3.15 ± 1.48ï¼½ vs ï¼»4.63 ± 1.17ï¼½ µmol/L, P < 0.05), but a decreased level of CysGly (ï¼»12.79 ± 3.18ï¼½ vs ï¼»5.94 ± 0.99ï¼½ µmol/L, P < 0.05). CONCLUSIONS: The method of reversed-phase UPLC-FL detection established in this study has made it possible simultaneous detection of Hcy, Cys, CysGly and GSH in the seminal plasma, which is applicable to laboratory research and clinical routine examination. Patients with hyperuricemia may incur oxidative damage to the reproductive system.


Asunto(s)
Hiperuricemia , Semen/química , Compuestos de Sulfhidrilo , Cisteína/análisis , Glutatión/análisis , Homocisteína/análisis , Humanos , Hiperuricemia/diagnóstico , Compuestos de Sulfhidrilo/análisis
17.
J Agric Food Chem ; 69(50): 15290-15300, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34894689

RESUMEN

Polyphenolic fractions from Garnacha, Tempranillo, and Moristel grapes were reconstituted to form model wines of identical pH, ethanol, amino acid, metal, and varietal polyfunctional mercaptan (PFM) contents. Models were subjected to a forced oxidation procedure at 35 °C and to an equivalent treatment under strict anoxia. Polyphenolic profiles significantly determined oxygen consumption rates (5.6-13.6 mg L-1 day-1), Strecker aldehyde (SA) accumulation (ratios max/min around 2.5), and levels of PFMs remaining (ratio max/min between 1.93 and 4.53). By contrast, acetaldehyde accumulated in small amounts and homogeneously (11-15 mg L-1). Tempranillo samples, with highest delphinidin and prodelphinidins and smallest catechin, consume O2 faster but accumulate less SA and retain smallest amounts of PFMs under anoxic conditions. Overall, SA accumulation may be related to polyphenols, producing stable quinones. The ability to protect PFMs as disulfides may be negatively related to the increase in tannin activity, while pigmented tannins could be related to 4-methyl-4-mercaptopentanone decrease.


Asunto(s)
Vitis , Vino , Aldehídos , Polifenoles , Compuestos de Sulfhidrilo/análisis , Vino/análisis
18.
Rev Assoc Med Bras (1992) ; 67(7): 1026-1032, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34817518

RESUMEN

OBJECTIVE: Many chronic diseases such as malignancy, cardiovascular diseases, endothelial dysfunction, and autoimmune diseases, which have been shown to be related to vitamin D in various studies; have similar relations with CTRP-9, TNFα, and thiol-disulfide hemostasis. We aimed to contribute to the literature by evaluating the relationship between CTRP-9, TNFα, and thiol-disulfide hemostasis and vitamin D levels, which we thought may have some effects on the pathogenesis of vitamin D deficiency. METHODS: In our study, 78 female volunteers older than 18 years were included. Volunteers were divided into three groups according to the reference values of vitamin D levels. Biochemical parameters, CTRP-9, TNFα, and thiol/disulfide hemostasis tests taken from all volunteers were studied. RESULTS: In this study, there was a significant difference in CTRP-9, TNFα, total thiol (TT), native thiol (NT), DIS (disulfide), TT/DIS, and NT/DIS levels in vitamin D groups (p<0.05). There was a significant negative correlation between vitamin D and TNFα and DIS, while a significant positive correlation was found with CTRP-9, TT, NT, TT/DIS, and NT/DIS (p<0.05). CONCLUSIONS: It was determined that vitamin D deficiency causes a significant decrease in CTRP-9 level and a significant increase in TNFα level, as well as an increase in thiol/disulfide hemostasis in favor of disulfide, which may be a risk factor for increased oxidative stress. We considered that these changes may play mediator roles for many chronic diseases and metabolic disorders that are increasing in frequency due to vitamin D deficiency.


Asunto(s)
Disulfuros , Factor de Necrosis Tumoral alfa , Biomarcadores , Femenino , Hemostasis , Homeostasis , Humanos , Estrés Oxidativo , Compuestos de Sulfhidrilo , Vitamina D
19.
Environ Pollut ; 291: 118221, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34740294

RESUMEN

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.


Asunto(s)
Insecticidas , Plantones , Ecosistema , Insecticidas/toxicidad , Lechuga , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Compuestos de Sulfhidrilo , Azufre
20.
Anal Chem ; 93(46): 15358-15364, 2021 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-34767337

RESUMEN

Tip-enhanced Raman spectroscopy (TERS) is a powerful tool for nondestructive and label-free surface chemical characterization at nanometer length scales. However, despite being considered nondestructive, the interaction of the TERS probe used in the analysis can alter the molecular organization of the sample. In this study, we investigate the role of the atomic force microscopy (AFM) feedback (contact mode and tapping mode) on molecular perturbation in TERS analysis of soft samples using a self-assembled monolayer (SAM) of 2-chloro-4-nitrobenzene-1-thiol (Cl-NBT) as a test sample. Surprisingly, the tapping mode shows a consistently higher TERS signal resulting from a minimal perturbation of the Cl-NBT SAM compared to the contact mode. This study provides novel insights into the choice of the correct AFM-TERS operation mode for nanoscale chemical analysis of soft and delicate samples and is expected to expedite the growing application of TERS in this area.


Asunto(s)
Espectrometría Raman , Compuestos de Sulfhidrilo , Microscopía de Fuerza Atómica
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