Thiol Ratios Research Articles

Gold Nanorod Amalgamation: Machine Learning Empowered Discrimination of Biothiol and Thiol Ratios.

Biothiols, characterized by thiol groups, exhibit remarkable affinity for certain metals, playing pivotal roles in intracellular and extracellular biological processes. Fluctuations in their levels profoundly impact overall physiological health. Despite the development of various probes for biothiol detection and quantification, their inability to monitor thiol-to-disulfide state transitions persists as a limitation. Given their association with pathologies, early detection remains imperative. Gold nanorod (AuNR)-based colorimetric probes have garnered attention for their utility in visual diagnostic assays. Herein, we present a cost-effective, and sensitive multicolor ratio measuring probe enabling on-site simultaneous identification, discrimination, and quantification of essential biothiols─cysteine (CYS), glutathione (GSH), cystine (CYSS), and glutathione disulfide (GSSG)─while also quantifying thiol-to-disulfide ratios. Our investigation clarifies the probe's functionality, elucidating etching and antietching mechanisms based on sulfhydryl group coordination with Hg2+. This coordination impedes gold amalgam formation, facilitating discriminative detection via AuNR size and aspect ratio modulation, validated by transmission electron microscopy. Notably, distinct rainbow-like fingerprint patterns were discernible both visually and spectroscopically for the aforementioned biothiols and their respective thiol-to-disulfide ratios. Subsequent qualitative and quantitative analyses via linear discriminant analysis (LDA) and partial least squares regression revealed linear correlations over broad concentration ranges (CYS: 1.9-40 μmol L-1, GSH: 3.2-200.0 μmol L-1, CYSS: 2.0-70.0 μmol L-1, GSSG: 3.7-100.0 μmol L-1), with detection limits of 0.66 μmol L-1 (CYS), 1.07 μmol L-1 (GSH), 0.69 μmol L-1 (CYSS), and 1.24 μmol L-1 (GSSG). Moreover, thiol-to-disulfide ratios exhibited linear patterns within 0.2-5 μmol L-1, with detection limits of 0.13 and 0.09 μmol L-1, and exceptional analytical sensitivities of 32.648 and 49.782 for (CYS/CYSS) and (GSH/GSSG), respectively. Lastly, we evaluated the probe's performance in complex matrices relative to aqueous media, both quantitatively and qualitatively.

Synthesis of vinyl functionalized polyurethane acrylate oligomers and their photopolymerization via thiol-ene click reaction

Functional polyvinylethylene glycols (PVEGs) with different central structures were synthesized by Pd/B synergistic catalysts and reacted with isophorone diisocyanate (IPDI) and 2-hydroxyethyl methacrylate(HEMA) to prepared pendent vinyl-functional polyurethane acrylates (VFPUAs). The photopolymerization of the obtained VFPUAs with pentaerythritol tetra(3-mercaptopropionate) (PETMP) in the presence of a photoinitiator proceeded smoothly via thiol-ene photo-click reaction to give a series of crosslinked materials by the variation of the chemical structure of VFPUAs and a ratio of thiols and enes. The curing behavior was studied by FT-IR and the properties of crosslinked materials were characterized by the test of gel content, swelling ratio and water absorption. The dynamic mechanical properties, mechanical properties, thermogravimetry and surface properties of the crosslinked materials were investigated and the performance of coating for the crosslinked film materials was also characterized. The crosslinked film materials can be further functionalized by post-crosslinking modification through thiol-ene photo-click reaction.

Assessment of thiol-disulfide and glutathione homeostasis after levothyroxine replacement in individuals with autoimmune or nonautoimmune hypothyroidism.

Thyroid hormones are known to affect the biosynthesis and degradation of antioxidant compounds, suggesting a possible link between hypothyroidism and oxidative stress. However, there is no clear consensus in the literature regarding this association. The aim of this study was to evaluate oxidative stress markers (extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis) in patients with hypothyroidism due to autoimmune (Hashimoto's thyroiditis) or nonautoimmune thyroid disease rendered euthyroid after levothyroxine replacement. The study included 116 patients admitted to the Taksim Training and Research Hospital (Istanbul, Türkiye). Of these, 50 had hypothyroidism due to Hashimoto's thyroiditis (HT group), 30 had nonautoimmune hypothyroidism (NAIH group), and 36 were healthy controls (control group). All participants were women. Extracellular thiol-disulfide homeostasis and intracellular glutathione homeostasis tests were assessed as oxidative stress markers. Thiol-disulfide homeostasis in both HT and NAIH groups was shifted toward the oxidative spectrum. Compared with the control group, the HT and NAIH groups had lower levels of native (p < 0.001 and p = 0.001, respectively) and total (p = 0.002 and p = 0.012, respectively) thiol, as well as a lower native thiol/total thiol ratio (p < 0.001 for both). The HT group also had higher disulfide levels than the control group (p = 0.027). Reduced glutathione (GSH) and oxidized glutathione (GSSG) values were comparable across all three groups, but the HT and NAIH groups had higher GSSG/GSH (p < 0.001 for both) and GSSG/(GSH+GSSG) ratios (p = 0.003 and p = 0.005, respectively), along with lower GSH/(GSH+GSSG) ratio (p = 0.001 and p = 0.002, respectively) than the control group. Levothyroxine replacement was ineffective in ameliorating oxidative stress in patients with hypothyroidism due to Hashimoto's thyroiditis or nonautoimmune causes, as extracellular thiol-disulfide homeostasis was notably altered in these patients compared with healthy controls. The findings of this study suggest that oxidative stress remains a prevailing issue in patients with autoimmune or nonautoimmune hypothyroidism even after euthyroidism is restored.

Continuous Thymoquinone Administration Mitigates Sodium Iodate-Induced Retinal Degeneration in Rats

Purpose This study aimed to investigate the protective or therapeutic effect of thymoquinone (TQ) in a retinal degeneration rat model and its relationships with the retina ultrastructure, heme oxygenase 1 (HO-1), caspase-3, and RPE65 expressions and to determine whether TQ has a therapeutic effect at the biochemical level. Methods A total of 25 adult Wistar albino rats were divided into the following treatment groups: saline (control: CONT), CO (corn oil), sodium iodate (SI), TQ + SI, and SI + TQ injection groups. Retina morphology, RPE65, HO-1, and caspase-3 expression levels were evaluated using immunohistochemistry, and optical density was determined using ImageJ. Ultrastructural evaluations were performed with electron microscopy. Thiol-disulfide homeostatic parameters were examined in serum samples. Results Outer nuclear layer (ONL) thickness was significantly higher in the SI + TQ group compared to the SI group. The RPE65 expression significantly decreased in the SI group compared with the CONT and CO groups. A significant increase in RPE65 expression level and a significant decrease in caspase-3 expression level were found in the SI + TQ group compared with the SI group. The increase in HO-1 expression level was significantly higher in the TQ treatment groups, particularly in the SI + TQ group. In the SI and TQ + SI groups, the ONL thickness significantly decreased with a significant increase in caspase-3 expression compared to the CONT and CO groups. In the treatment groups, decreased organelle damage was observed on electron microscopy. In the SI + TQ group, the disulfide/native thiol and disulfide/total thiol ratios were significantly lower than all other groups, while the native/total thiol ratio was significantly higher than the other experimental groups. Conclusions The present study provides evidence that continuous TQ treatment can increase HO-1 and RPE65 expression and decrease apoptosis (caspase-3 levels), thereby preserving the retina at the ultrastructural level. Moreover, TQ administration can maintain thiol/disulfide homeostasis in SI-induced retinal degeneration-modelled rats.

Photopolymerization of polyvinylethylene glycol oligomers by thiol‐ene click reaction

AbstractFunctional polyvinylethylene glycols (PVEGs) with pendent vinyl groups were synthesized by Pd/B synergistic catalysts and their structures were characterized by 1H NMR and FT‐IR. The photopolymerization of the obtained PVEGs with multifunctional thiols in the presence of a photoinitiator proceeded smoothly via thiol‐ene photo‐click reaction to give a series of crosslinked materials by the variation of the molecular weight of PVEGs and a ratio of thiols and enes. The curing behavior was studied by FT‐IR and the properties of crosslinked materials were characterized by the test of gel content, swelling ratio, and water absorption. The dynamic mechanical analysis, mechanical properties, thermogravimetry, and surface properties of the crosslinked materials were investigated and the performance of coating for the crosslinked film materials was also characterized. The crosslinked film materials can be further functionalized by post‐crosslinking modification through thiol‐ene photo‐click reaction.

Investigation of Thiol/Disulfide Homeostasis and Clinical Parameters in Rosacea Patients According to Skin Subtypes.

Background/Objective: The aim of this study was to compare thiol/disulfide homeostasis and clinical parameters of rosacea patients across skin subtypes of the disease and healthy controls. Methods: This prospective study included 90 rosacea patients with different skin subtypes (phymatous, erythematotelangiectatic and papulopustular) and ocular involvement and 30 healthy controls. Plasma native thiol (NT), total thiol (TT) and disulfide levels of the patients and controls were measured using an automated spectrophotometric method, and disulfide/native thiol ratio (DNTR), disulfide/total thiol ratio (DTTR) and native thiol/total thiol ratio (NTTR) were calculated. Tear breakup time (TBUT), meiboscore, Schirmer, ocular surface disease index (OSDI) and rosacea-specific quality of life scale (RosaQoL) were measured clinically. Results: Disulfide, DNTR and DTTR were significantly higher, and NT, TT and NTTR were significantly lower in the rosacea patients compared to the controls (p < 0.001). TBUT and Schirmer were significantly lower, and meiboscore and OSDI were significantly higher in the patients compared to the controls (p < 0.01). According to the skin subtypes, disulfide, DNTR and DTTR were significantly higher, and NTTR was significantly lower in the erythematotelangiectatic subtype compared to the other subtypes (p < 0.002). TBUT was significantly lower, and RosaQol was significantly higher in the erythematotelangiectatic subtype (p < 0.0083). Strong correlations were found between DNTR and TBUT and between DNTR and Meiboscore in all subtypes (p < 0.005), while there were strong correlations between DNTR and OSDI and between DNTR and RosaQol only in the erythematotelangiectatic and papulopustular subtypes (p < 0.05). Conclusions: The thiol/disulfide homeostasis shifted towards disulfides, an indicator of oxidative stress in rosacea, and this was more pronounced in the erythematotelangiectatic subtype. The impairment in TBUT and RosaQol was also more prominent in the erythematotelangiectatic subtype and strongly associated with the DNTR.

Effects of N-acetylcysteine on sciatic nerve healing: A histopathological, functional, and biochemical study of the rat sciatic nerve.

This study aims to evaluate the histopathological, biochemical, and functional effects of N-acetylcysteine (NAC), which has antioxidant, anti-inflammatory, and cytoprotective activity, on nerve regeneration in rats with sciatic nerve crush (axonotmesis) injury. This study used 16 male Wistar rats, which were divided into treatment and control groups. A standard axonotmesis-type surgical injury was induced in the left sciatic nerves of all rats. The treatment group was given 300 mg/kg of intraperitoneal NAC once a day, whereas the control group received an equal volume of saline solution. After conducting gait analyses, the sciatic functional index (SFI) was used for functional assessment. After gait analysis, all animals were euthanized. Blood samples were examined biochemically. The left sciatic nerves and left triceps surae muscles were examined histopathologically. Histopathologically, the thickness of the perineurium, axonal degeneration, axonolysis, edema, inflammation, muscle atrophy, and muscle degeneration were all significantly lower in the treatment group (p<0.05). Functionally, SFI-1, SFI-2, and SFI-3 were significantly higher in the treatment group (p<0.05). Biochemically, while the native thiol level and native thiol/total thiol ratio were significantly higher in the treatment group (p<0.003), the disulfide/total thiol ratio was significantly higher in the control group (p<0.005). Significant correlations were found between six of the seven gait parameters and the histopathological findings (p<0.05). Our study results suggest that NAC may contribute positively to the histopathological and functional recovery of sciatic nerve injury in rats. Furthermore, NAC may have an antioxidant effect on thiol-disulfide homeostasis at a biochemical level. We believe that NAC has a stimulatory effect on healing following nerve injuries.

Preliminary results of clinical, biochemical, and radiological investigation into the oxidative status in patients with rotator cuff tendinopathy.

We investigated oxidative status in patients with rotator cuff tendinopathy (RCT) and evaluated their relationship with radiological and clinical parameters. In this cross-section study, 88 patients with RCT (59 males and 29 females) and 86 healthy controls (66 males, 20 females) were enrolled. The sample consisted of nontraumatic patients who are suffering from shoulder pain because of rotator cuff disease, which was established by clinical tests and MRI scanning. Oxidative stress in patients with RCT was analyzed via the dynamic thiol/disulfide homeostasis (TDH). Thiol/disulfide homeostasis was measured by a new colorimetric method. Furthermore, oxidative stress was indirectly measured by serum total oxidant status (TOS), oxidative stress index (OSI), and total antioxidant capacity (TAC). Serum disulfide levels and the other oxidative stress parameters of the RCT group were significantly greater than those of the control group (P < .001 for all), whereas the anti-oxidative stress parameters remained unchanged (P > .05 for all). The lowest and highest serum disulfide levels were detected in patients with grades 1 and 3, respectively (P < .001). Furthermore, in a multiple regression analysis, the disulfide/natural thiol ratio (β=-4.886, P = .004) and the MRI grading (β=0.314, P=.001) were independently associated with the Western Ontario Rotator Cuff Index WORC score. We found an association between the levels of various serum markers of oxidative injury, especially serum disulfide levels, and the increasing severity of RCT. Thiol/disulfide homeostasis seems to play a critical role in RCT, both in the beginning and during the progression of disease.

Utility of thiol/disulphide homeostasis as a biomarker for acute appendicitis: a systematic review and meta-analysis.

The aim of this study was to analyze the role of thiol/disulfide homeostasis (TDH) parameters as an indicator of oxidative stress in acute appendicitis (AA). PubMed, EMBASE, Web of Science, and Scopus databases were systematically searched. Studies reporting on TDH in AA (both complicated and uncomplicated cases) were included. The comparator group were healthy controls. The TDH domain was compared between the groups using anti-oxidant parameters, namely native thiol and total thiol levels, and native thiol/total thiol ratio; and oxidant parameters, namely disulfide level, disulfide/native thiol ratio, and disulfide/total thiol ratio. The statistical analysis was performed using a random-effects model. The methodological quality of the studies was assessed utilizing the Newcastle-Ottawa scale. Eleven studies with a total of 926 subjects, comprising 457 patients with uncomplicated appendicitis, 147 with complicated appendicitis, and 322 healthy controls were included. Our study demonstrated significantly increased oxidative stress in AA as compared to healthy controls in all TDH parameters and significantly lower total thiol levels in complicated AA as compared to uncomplicated AA. Due to a poor methodological quality in five out of eleven studies, future prospective studies with adequate power are essential to validate these observations and refine the diagnostic approaches to AA.

Thiol/Disulfide Ratios, HOMA Score, and Quality of Sleep in Renal Transplant Recipients Without Diabetes.

Thiols play an important role in defense against reactive oxygen species. We aimed to evaluate the relation between oxidative stress, glucose tolerance, and sleep quality in kidney transplant recipients without diabetes. We enrolled 95 kidney transplant recipients without diabetes from living and deceased donors with stable allograft function and 60 healthy controls. We included recipients who received a kidney from a living donor with a first-degree relation. Insulin resistance was determined using the Homeostasis Model Assessment score. Native thiol, total thiol, and disulfide levels were measured, and disulfide versus native thiol/total thiol ratios were calculated from all patients. We used the Pittsburg Sleep Quality Index to assess sleeping patterns. According to standard cutoff value of the index (≤5 indicates good quality sleep; >5 indicates poor sleep quality), we stratified kidney transplant recipients as group 1 (Pittsburg Sleep Quality Index ≤5; n = 41) and group 2 (Pittsburg Sleep Quality Index >5; n = 54). In correlation analysis, Pittsburg Sleep Quality Index was positively correlated with age, the Homeostasis Model Assessment score, body mass index, serum disulfide levels, disulfide/total thiol ratio, and native/total thiol ratio. The Pittsburgh Sleep Quality Index was negatively correlated with total thiol levels. In subgroup analysis, the Homeostasis Model Assessment score, disulfide levels, and disulfide/total thiol and native/total thiol ratios were significantly lower in group 1; however, total thiol level was significantly higher in this group. In multivariate regression analysis, age, the Homeostasis Model Assessment score, disulfide/total thiol ratio, and renal resistivity index were detected as predictors of sleep quality score. Sleep quality moderates oxidative stress identified by thiol-disulfide homeostasis and insulin resistance in renal transplant recipients without diabetes.

Synthesis and structural characterization of picolinamide and thiol chelated Pt(II) complexes: Their kinetics & mechanism and theoretical approach

Picolinamide is a versatile chelating ligand and it reveals peculiar behaviour for metal chelation, particularly for its amide group. The bonding mode of N & O donor centres of an amide group depends on the metal ion, their associated charge and the other associated ligands in metal complexes. Picolinamide (pica) based Pt(II) complex C1 to C4 were synthesized and their bonding mode with Pt(II) was established by different spectroscopic analyses and theoretical approaches for their structural importance and potential anticancer activity. The complex [Pt(pica)Cl2]; C1 was synthesized and its hydrolyzed product [Pt(pica)(OH2)2](ClO4)2; C2 was obtained from hydrolysis of complex C1. The kinetic and mechanistic study for the interaction of complex C2 with l-cysteine (l-cys) and N-acetyl-l-cysteine (N-ac-l-cys) was performed in pseudo-first-order reaction condition to evaluate the rate constants, rate equation, enthalpy of activation (ΔHǂ) and entropy of activation (ΔSǂ). Sulfur chelated complex [Pt(pica)(l-cys)]+; C3 and [Pt(pica)(N-ac-l-cys)]; C4 were obtained when a 1:1 M ratio of C2 and thiol are mixed separately. Theoretical investigation on drug likeness property was evaluated by PASS prediction software. The theoretical approach on structural properties like; structural optimization, HOMO-LUMO energy, TD-DFT simulation, MEP and reactivity descriptors of the complexes were executed and analyzed with the Gaussian09 software package. Molecular docking of the complexes was executed with DNA and BSA.

Self-healing photo-polymerized thiol-ene networks utilizing bio-based hexaallylated compounds derived from L-cystine and citric acid

Bio-based vitrimers have received considerable attention owing to their contributions to carbon neutrality and resource and energy savings. The photopolymerization of hexaallylated compounds (A6CST and A6UDC) derived from L-cystine and citric acid with disulfide-containing polyether dithiol (LP-12) and pentaerythritol-based tetrathiol (S4P) at an allyl:thiol ratio of 1:1 produced thiol-ene network films. Fourier-transform infrared spectroscopy of the cured films revealed that the thiol-ene reaction of the thiol and allyl groups was almost complete. Degrees of swelling of the cured films decreased with an increasing LP-12/S4P ratio. The A6CST- and A6UDC-cured films with higher flexible LP-12 fractions (i.e., higher disulfide contents) exhibited lower glass transition temperatures (Tgs), tensile strengths, and tensile moduli, and could be healed by treatment at a lower temperature and shorter time. The A6CST/S4P cured film was healed by treating at 100 ℃ for 24 h, whereas the A6UDC/S4P cured film without disulfide bond was not healed by the same treatment. The A6CST-based film with the highest LP-12/S4P ratio exhibited the highest healing efficiency (99 %) after treatment at room temperature for 10 h, and self-healed at least three times.

Unveiling the link: Helicobacter pylori infection and impact on ischemia modified albumin, thiol, and disulfide levels

Abstract Objectives The objective of this research was to explore the link between Helicobacter pylori (H. pylori) infection and alterations in ischemia modified albumin (IMA), thiol, and disulfide levels, with a focus on their potential clinical implications. Methods We carried out a cross-sectional study, enrolling 153 patients who underwent upper gastrointestinal endoscopy between March and July 2023. Biopsies were obtained from the stomach antrum to diagnose H. pylori. Biochemical parameters, including IMA, thiol, and disulfide, were measured in fasting blood samples. A statistical analysis, including receiver operating characteristic curve analysis, was performed to assess the diagnostic potential of these biomarkers. Results In this study, a total of 153 patients were included, of whom 99 tested positive for H. pylori and 54 tested negative. The H. pylori-positive group exhibited significantly higher levels of disulfide, disulfide/native thiol ratio, disulfide/total thiol ratio, and IMA compared to the H. pylori-negative group (p≤0.05 for all parameters). In contrast, the native thiol/total thiol ratio was significantly lower in the H. pylori-positive group (p≤0.05). Conclusions Our study’s findings of elevated disulfide levels in H. pylori-positive individuals suggest a potential disruption in redox balance associated with H. pylori infection. This study contributes to the understanding of H. pylori’s systemic effects on biochemical markers, offering insights into their diagnostic utility.

Comparative analysis of thiol-disulfide homeostasis dynamics between elective cesarean section and uncomplicated vaginal delivery: insights into perinatal oxidative balance.

Thiols are organic compounds containing sulfhydryl groups that exert antioxidant effects via dynamic thiol-disulfide homeostasis. The shift towards disulfide indicates the presence of an oxidative environment. Different modes of delivery can affect thiol-disulfide homeostasis. Accordingly, we planned this research to evaluate the effects of the mode of delivery on thiol-disulfide homeostasis in both maternal serum and fetal cord blood samples. We conducted a prospective case-control study involving two groups: vaginal delivery (n=50) and elective cesarean section (CS) (n=45). The vaginal delivery group exclusively comprised uncomplicated term deliveries, while the CS group included pregnant individuals with scheduled cesarean deliveries due to the absence of spontaneous labor onset. Maternal serum and fetal cord blood samples were collected, and thiol-disulfide exchanges were analyzed using an automated method capable of measuring both aspects of the thiol-disulfide balance. The levels of native thiol (-SH) and total thiol in both maternal serum and fetal cord blood samples were significantly higher in the vaginal delivery group than those in the CS group. An important discovery of our study was that fetal cord disulfide (-SS) level, which may reflect oxidative stress, was higher in newborns born via vaginal delivery when examined alone. However, in both maternal and fetal cord blood, the combined ratios, SS/SH ratio (%), SS/Total thiol ratio (%), and SH/Total thiol ratio (%) were observed to be similar between the groups in both maternal and fetal cord blood. It was observed that as the mother's weight gained during pregnancy increased, SS/SH and SS/total thiol increased (positive correlation), while SH/total thiol decreased (negative correlation). Our results showed that the dynamic thiol-disulfide homeostasis was greatly influenced by the way of delivery and supported the idea that vaginally-delivered infants may have more oxidative stress.

Physical frailty is related to oxidative stress through thiol/disulfide homeostasis parameters.

To evaluate relationship between frailty and oxidative stress through thiol/disulfide homeostasis parameters [Native thiol (NT), total thiol (TT), and disulfide levels (D), disulfide-native thiol (D/NT), disulfide-total thiol (D/TT), native thiol-total thiol (NT/TT) ratios, and ischemia-modified albumin levels (IMA)]. In total, 139 community-dwelling older adults were included. The frailty status, defined by the FRIED frailty index (FFI) and Clinical Frailty Scale (CFS), and comprehensive geriatric assessment results compared with thiol/disulfide homeostasis parameters and ischemia-modified albumin levels. NT and TT levels were significantly lower in the frail group (respectively; p = 0.014, p = 0.020). The FFI scores were correlated with the levels of NT, TT, D/NT, D/TT, and NT/TT (respectively; r = - 0.25, r = - 0.24, r = 0.17, r = 0.17, r = - 0.17). The significant correlation could not be retained with the CFS scores. In ROC analysis, the AUC for NT was calculated as 0.639 in diagnosing frailty according to the FFI (95% CI 0.542-0.737), AUC was 0.638 for TT (95% CI 0.540-0.735), and AUC was 0.610 for NT/TT (95% CI 0.511-0.780). The AUC was calculated as 0.610 for both D/NT and D/TT in diagnosing physical frailty (95% CI 0.511-0.708). Thiol/disulfide homeostasis parameters can be a potential biomarker in diagnosing physical frailty. However, further studies are needed for diagnosing frailty defined with cumulative deficit models.

Dynamic thiol/disulfide homeostasis and myeloperoxidase levels in Gilbert's syndrome with mild hyperbilirubinemia.

This study aimed to compare dynamic thiol/disulfide homeostasis and myeloperoxidase (MPO) levels in patients with Gilbert's syndrome (GS) and healthy controls. Thiol/disulfide homeostasis and MPO levels are both associated with increased progression of atherosclerosis. The study included a total of 130 voluntary participants comprising 65 patients with GS and 65 healthy controls. These patients were selected randomly and dynamic thiol/disulfide homeostasis, MPO, complete blood count results, and biochemistry and lipid parameters were evaluated. Patients with known chronic diseases, medication usage, and acute infections were excluded from the study. Serum total thiol and native thiol levels were measured using the fully automated colorimetric method, while serum MPO levels were measured using the sandwich ELISA method. We found that patients with GS had significantly higher total thiol (352.3±38.6 vs. 317.9±47.9, p<0.001) and native thiol (386.6±42.6 vs. 348.0±51.1, p<0.001) and significantly lower disulfide (15.7±4.0 vs. 17.3±4.0, p=0.022) and MPO (130.7 vs. 166.3, p=0.006). In patients with bilirubin of <1 mg/dL, total thiol and native thiol levels were lower and disulfide, disulfide/native thiol (DNT) and disulfide/total thiol (DTT) ratios, and MPO levels were higher. Patients with bilirubin of <1 mg/dL also had higher total cholesterol. In these patients with GS, the thiol/disulfide balance shifted towards thiols and proinflammatory MPO levels were lower. When bilirubin was <1 mg/dL, disulfide, DNT and DTT ratios, and MPO were higher. Bilirubin levels affected all parameters of thiol/disulfide homeostasis and MPO levels independently of other risk factors. In light of our results, we suggest that mild hyperbilirubinemia in cases of GS has an anti-inflammatory and antioxidant effect and may be protective against atherosclerosis.

Preparation of pH-responsive reversible wettable surfaces and application for oil-water separation

With the continuous development of society, the discharge of oily wastewater in daily life and industry has gradually increased, causing considerable damage to the environment, and how to effectively treat oily wastewater is an urgent problem. In this paper, a simple method is proposed to prepare superhydrophobic stainless steel mesh with pH response. The relationship between the ratio of mixed thiols and the surface wettability was explored, as well as the morphology, chemical composition, and pH-responsive mechanism of the stainless steel mesh surface were analyzed, and the separation efficiency, recycling ability, and backwashing ability of the mesh were explored by oil–water separation experiments. It was found that when the molar fraction of 11-mercaptoundecanoic acid and 1-decanethiol in the mixed mercaptan was 2:3, the water contact angle of the surface at this point was 156.5 ± 1°, with pH response characteristics and good oil–water separation efficiency, backwashing and recycling capabilities.

Cascade Reaction of Thiol-Disulfide Exchange Potentiates Rapid Fabrication of Polymer Hydrogels.

We report a rapid cross-linking strategy for the fabrication of polymer hydrogels based on a thiol-disulfide cascade reaction. Specifically, thiolated polymers (e.g., poly(ethylene glycol), hyaluronic acid, sodium alginate, poly(acrylic acid), and poly(methylacrylic acid)) can be cross-linked via the trigger of Ellman's reagent, resulting in the rapid formation of hydrogels over 20-fold faster than that via the oxidation in air. The gelation kinetics of hydrogels can be tuned by varying the polymer concentration and the molar ratio of Ellman's reagent and free thiols. The obtained hydrogels can be further functionalized with functional moieties (e.g., targeting ligands) for the selective adhesion of cells. This approach is applicable to various natural and synthetic polymers for the assembly of hydrogels with a minimized gelation time, which is promising for various biological applications.

The effect of remifentanil and dexmedetomidine on dynamic thiol/disulfide balance in patients undergoing coronary artery bypass surgery: a prospective case-control study.

It is established that the balance of serum thiols is disrupted in favor of oxidants in coronary artery disease, and the cardiopulmonary bypass pump used during coronary artery bypass surgery disrupts this balance in favor of oxidants. In this study, we investigated the antioxidant effects of remifentanil or dexmedetomidine on thiol-disulfide balance and paraoxonase-1 (PON-1) levels during on-pump coronary artery bypass surgery. A total of 100 patients who underwent on-pump coronary artery bypass grafting surgery between May 2018 and December 2018 were included in the study. Patients were divided into two groups: the remifentanil group (Group R) and the dexmedetomidine group (Group D). Venous blood samples were obtained from the patients after induction of anesthesia [Time 1 (T-1)], then after cross-clamping of the aorta (T-2), after removal of the cross-clamp (T-3), 10 minutes after the end of protamine infusion (T-4), and 24 hours postoperatively (T-5). Serum total thiol, native thiol, disulfide, and PON-1 levels were evaluated. Total thiol, disulfide, PON-1, native thiol/total thiol, total thiol/disulfide, and native thiol/disulfide levels were similar between the two groups. Native thiol levels were statistically significantly higher in group D compared to group R at T-3 and T-5 (p = 0.017 and p = 0.027, respectively). When T-1 and T-5 times were compared in intragroup measurements, disulfide levels were significantly lower, and native thiol/total thiol ratios were significantly higher at T-5 (p < 0.001). In conclusion, in light of the data obtained from this study, it can be concluded that dexmedetomidine used during surgery has a better contribution to oxidant-antioxidant balance than remifentanil in patients undergoing coronary artery bypass surgery with the on-pump method.

Flexible Allyl-Modified Gelatin Photoclick Resin Tailored for Volumetric Bioprinting of Matrices for Soft Tissue Engineering.

Volumetric bioprinting (VBP) is a light-based 3D printing platform, which recently prompted a paradigm shift for additive manufacturing (AM) techniques considering its capability to enable the fabrication of complex cell-laden geometries in tens of seconds with high spatiotemporal control and pattern accuracy. A flexible allyl-modified gelatin (gelAGE)-based photoclick resin is developed in this study to fabricate matrices with exceptionally soft polymer networks (0.2-1.0kPa). The gelAGE-based resin formulations are designed to exploit the fast thiol-ene crosslinking in combination with a four-arm thiolated polyethylene glycol (PEG4SH) in the presence of a photoinitiator. The flexibility of the gelAGE biomaterial platform allows one to tailor its concentration spanning from 2.75% to 6% and to vary the allyl to thiol ratio without hampering the photocrosslinking efficiency. The thiol-ene crosslinking enables the production of viable cell-material constructs with a high throughput in tens of seconds. The suitability of the gelAGE-based resins is demonstrated by adipogenic differentiation of adipose-derived stromal cells (ASC) after VBP and by the printing of more fragile adipocytes as a proof-of-concept. Taken together, this study introduces a soft photoclick resin which paves the way for volumetric printing applications toward soft tissue engineering.