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1.
Biotechnol J ; 19(6): e2400082, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38896412

RESUMEN

Saccharomyces cerevisiae is important for protein secretion studies, yet the complexities of protein synthesis and secretion under endoplasmic reticulum (ER) stress conditions remain not fully understood. ER stress, triggered by alterations in the ER protein folding environment, poses substantial challenges to cells, especially during heterologous protein production. In this study, we used RNA-seq to analyze the transcriptional responses of yeast strains to ER stress induced by reagents such as tunicamycin (Tm) or dithiothreitol (DTT). Our gene expression analysis revealed several crucial genes, such as HMO1 and BIO5, that are involved in ER-stress tolerance. Through metabolic engineering, the best engineered strain R23 with HMO1 overexpression and BIO5 deletion, showed enhanced ER stress tolerance and improved protein folding efficiency, leading to a 2.14-fold increase in α-amylase production under Tm treatment and a 2.04-fold increase in cell density under DTT treatment. Our findings contribute to the understanding of cellular responses to ER stress and provide a basis for further investigations into the mechanisms of ER stress at the cellular level.


Asunto(s)
Estrés del Retículo Endoplásmico , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Tunicamicina , Estrés del Retículo Endoplásmico/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Tunicamicina/farmacología , Regulación Fúngica de la Expresión Génica/genética , Ditiotreitol/farmacología , Ingeniería Metabólica/métodos , Pliegue de Proteína
2.
Chemosphere ; 361: 142435, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38797213

RESUMEN

An alternative metric to account for particulate matter (PM) composition-based toxicity is the ability of PM-species to generate reactive oxygen species (ROS) and deplete antioxidants, the so-called oxidative potential (OP). Acellular OP assays are the most used worldwide, mainly those based on ascorbic acid (AA) and dithiothreitol (DTT) depletion; OP values are calculated from AA/DTT concentration over time kinetic curves. Since a great variability in OP-DTT and OP-AA values can be found in the literature, the understanding of those factors affecting the kinetic rate of AA and DTT oxidation in the presence of PM-bound species will improve the interpretation of OP values. In this work, a kinetic study of the oxidation rate of AA and DTT driven by species usually found in PM (transition metals and naphthoquinone (NQ)) was carried out. In particular, the influence of the concentration of Cu(II), Fe(II), Fe(III), Mn(II), Mn(III), and 1,4-NQ, and the type of fluid used in the assay (phosphate buffer (PB), phosphate buffer saline (PBS) and artificial lysosomal fluid (ALF)) is analysed and discussed. The reaction orders with respect to the AA/DTT and the active compound, and the kinetic rate constants were also determined. The results show great variability in OP values among the studied species depending on the fluid used; the OP values were mostly higher in PB0.05 M, followed by PBS1x and ALF. Moreover, different species concentration-responses for OP-DTT/OP-AA were obtained. These differences were explained by the different reaction orders and kinetic rate constants obtained for each active compound in each fluid.


Asunto(s)
Ácido Ascórbico , Cobre , Ditiotreitol , Hierro , Manganeso , Naftoquinonas , Oxidación-Reducción , Cinética , Ácido Ascórbico/química , Naftoquinonas/química , Ditiotreitol/química , Hierro/química , Cobre/química , Manganeso/química , Material Particulado/química , Material Particulado/análisis , Antioxidantes/química , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/química
3.
Biomacromolecules ; 25(3): 1972-1977, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38359265

RESUMEN

A facile and green approach for the preparation of PEGn-NH2s from PEGn-N3s in water with DTT as the reduction reagent has been developed, avoiding the introduction of metal ions and difficulties in purification compared to the traditional synthesis process of PEGn-NH2s. A series of high-purity linear and multiarm PEGn-NH2s with different molecular weights were synthesized, demonstrating the versatility of this method. Additionally, HS-PEG45-NH2 with high fidelity of thiol and amine was easily prepared through the one-step two functional group conversion of N3-PEG45-S-S-PEG45-N3, and the PEG-based NH2-PEG@AuNPs were also prepared. This technology will promote the application of PEGn-NH2s in the fields of medicine and biomaterials.


Asunto(s)
Nanopartículas del Metal , Polietilenglicoles , Azidas , Ditiotreitol , Aminas , Oro
4.
Photochem Photobiol Sci ; 23(2): 271-284, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38305951

RESUMEN

Ultraviolet A (UVA) radiation, present in sunlight, can induce cell redox imbalance leading to cellular damage and even cell death, compromising skin health. Here, we evaluated the in vitro antioxidant and photochemoprotective effect of dithiothreitol (DTT). DTT neutralized the free radicals 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS·+), 2,2-diphenyl-1-picrylhydrazyl (DPPH·), and superoxide anion (O2·-) in in vitro assays, as well as the ferric ion (Fe3+) in the ferric reducing antioxidant power (FRAP) assay. We also evaluated the effect of DTT pre-treatment in L929 dermal fibroblasts and DTT (50 and 100 µM) led to greater cell viability following UVA-irradiation compared to cells that were untreated. Furthermore, the pre-treatment of cells with DTT prevented the increase of intracellular reactive oxygen species (ROS) production, including hydrogen peroxide (H2O2), lipid peroxidation, and DNA condensation, as well as the decrease in mitochondrial membrane potential (Δψm), that occurred following irradiation in untreated cells. The endogenous antioxidant system of cells was also improved in irradiated cells that were DTT pre-treated compared to the untreated cells, as the activity of the superoxide dismutase (SOD) and catalase (CAT) enzymes remained as high as non-irradiated cells, while the activity levels were depleted in the untreated irradiated cells. Furthermore, DTT reduced necrosis in UVA-irradiated fibroblasts. Together, these results showed that DTT may have promising use in the prevention of skin photoaging and photodamage induced by UVA, as it provided photochemoprotection against the harmful effects of this radiation, reducing oxidative stress and cell death, due mainly to its antioxidant capacity.


Asunto(s)
Antioxidantes , Peróxido de Hidrógeno , Humanos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Ditiotreitol/farmacología , Ditiotreitol/metabolismo , Peróxido de Hidrógeno/farmacología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Piel/efectos de la radiación , Rayos Ultravioleta , Necrosis , Fibroblastos
5.
Environ Pollut ; 347: 123666, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38417601

RESUMEN

In the context of air quality research, the collection and analysis of fine particulate matter (PM2.5, with a diameter less than 2.5 µm) and volatile organic compound (VOCs) play a pivotal role in understanding and addressing environmental issues across the Korean Peninsula. PM2.5 and VOCs were collected over 4-hr intervals from October 17 to November 26, 2021 during the 2021 Satellite Integrated Joint Monitoring of Air Quality campaign at Olympic Park in the Republic of Korea to understand the factors controlling air quality over the Seoul Metropolitan Area. Source apportionment was performed using the positive matrix factorization (PMF) model incorporating PM2.5 and VOCs. The factor identified by chlorinated VOCs as a major component was presumed to be due to transboundary influx and was referred to as the long-range transport factor. The long-range transport factor of PM2.5 was composed of NO3-, SO42-, NH4+, and di-carboxylic acids. Back trajectory analysis showed that the airflows originated from China and passed through the west coast of Korea to the Korean Peninsula. In the PMF results using PM2.5 and VOCs, long-range transport factors were identified in both analyses, and the high correlation observed between these factors confirms that they were transported from abroad. The dithiothreitol oxidation potential normalized to quinine showed the highest oxidation potential during the same period as the long-range transport factors increased. In conclusion, PM2.5 from external sources significantly contribute to elevated levels of dithiothreitol assay-oxidative potential (DTT-OP) in Korea. The toxic concentration, expressed as the mean ± standard deviation, was determined to be 0.29 ± 0.05 µM/m³, peaking at 0.39 µM/m³. This level is 1.8 times higher than that observed outside the event period. A notable increase in secondary pollutants was observed during these periods. These pollutants are known to enhance oxidative potential, thereby potentially impacting human health.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Compuestos Orgánicos Volátiles , Humanos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Ditiotreitol , Monitoreo del Ambiente/métodos , Estrés Oxidativo , Material Particulado/análisis , Emisiones de Vehículos/análisis , Compuestos Orgánicos Volátiles/análisis
6.
Environ Pollut ; 343: 123246, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38158012

RESUMEN

This study reports size-resolved dithiothreitol (DTT)-based oxidative potential (OP: total and water-soluble) in rural kitchens using liquefied petroleum gas (LPG), firewood (FW), and mixed biomass (MB) fuels in northeastern (NE) India. In comparison to LPG, volume-normalized total OP (OPtotal(v)DTT) was enhanced by a factor of ∼5 in biomass-using kitchens (74 ± 35 to 78 ± 42 nmol min-1 m-3); however, mass-normalized total OP (OPtotal(m)DTT) was similar between LPG and FW users and higher by a factor of 2 in MB-using kitchens. The water-insoluble OP (OPwi(v, m)DTT) fraction in OPtotal(v, m)DTT was greater than 50% across kitchens. Size distributions across kitchens and OPDTT categories ranged from unimodal to trimodal. OPws(v)DTT was driven by metals as well as organics across size fractions while OPwi(v)DTT was majorly constrained by metals with an increasing importance of organics in fine particles of biomass-using kitchens. Multiple linear regression analysis revealed that Cu and Ba explained 71% of the OPtotal(v)DTT variability in LPG-using kitchens, while water-soluble organic carbon (WSOC) and Ba were responsible for 44% variability in FW-using kitchens. Finally, the high internal dose of OPtotal(v)DTT (28-31 nmol min-1 m-3) in biomass-using kitchens established the severity of oxidative stress on the exposed population.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Petróleo , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , India , Aerosoles , Estrés Oxidativo , Ditiotreitol , Agua , Monitoreo del Ambiente , Contaminación del Aire Interior/análisis
7.
Biomolecules ; 13(11)2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-38002342

RESUMEN

Immature starfish oocytes isolated from the ovary are susceptible to polyspermy due to the structural organization of the vitelline layer covering the oocyte plasma membrane, as well as the distribution and biochemical properties of the actin cytoskeleton of the oocyte cortex. After the resumption of the meiotic cycle of the oocyte triggered by the hormone 1-methyladenine, the maturing oocyte reaches fertilizable conditions to be stimulated by only one sperm with a normal Ca2+ response and cortical reaction. This cytoplasmic ripening of the oocyte, resulting in normal fertilization and development, is due to the remodeling of the cortical actin cytoskeleton and germinal vesicle breakdown (GVBD). Since disulfide-reducing agents such as dithiothreitol (DTT) are known to induce the maturation and GVBD of oocytes in many species of starfish, we analyzed the pattern of the fertilization response displayed by Astropecten aranciacus oocytes pre-exposed to DTT with or without 1-MA stimulation. Short treatment of A. aranciacus immature oocytes with DTT reduced the rate of polyspermic fertilization and altered the sperm-induced Ca2+ response by changing the morphology of microvilli, cortical granules, and biochemical properties of the cortical F-actin. At variance with 1-MA, the DTT treatment of immature starfish oocytes for 70 min did not induce GVBD. On the other hand, the DTT treatment caused an alteration in microvilli morphology and a drastic depolymerization of the cortical F-actin, which impaired the sperm-induced Ca2+ response at fertilization and the subsequent embryonic development.


Asunto(s)
Actinas , Estrellas de Mar , Animales , Femenino , Masculino , Ditiotreitol/farmacología , Ditiotreitol/metabolismo , Actinas/metabolismo , Semen/metabolismo , Oocitos/metabolismo , Fertilización
8.
Cell Mol Biol (Noisy-le-grand) ; 69(7): 91-97, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715419

RESUMEN

It aimed to discuss the adoption of nanoparticle micro-infusion valves in the totally implantable venous access port (TIVAP) of tumor patients and analyze the self-care of patients after surgery. A total of 189 tumor patients who received TIVAP chemotherapy were selected from the day chemotherapy outpatient department of the Second People's Hospital of Lianyungang City from June to October 2021. The questionnaire survey was conducted to collect and analyze the general information about the patients and the patient's self-care ability. All the surveys and analyses were performed using a general information questionnaire, self-care competence scale, self-management efficacy scale, social support scale, and self-rating anxiety scale. Moreover, the nanoparticle micro-infusion valve was prepared, and its characterization, in vitro drug release, and cytotoxicity were studied. The self-management ability of patients was concentrated in the middle and high levels. Marital status, education level, and economic status all had a great impact on the patient's self-care ability. The infusion of dithiothreitol (DTT) increased the drug release of the nanoparticle micro-infusion valve. When pH=5.0, the drug-loaded nanoparticle micro-infusion valve release amount was greater than when pH=7.4. When pH=5.0 and pH=7.4, the cell survival rates under the drug-loaded nanoparticle micro-infusion valve were both lower than that without drug loading. Nanoparticle micro-infusion valves can specifically identify tumor cells, and have good adoption prospects in TIVAP implantation in tumor patients. Gender, marital status, education level, etc. all affected the self-care ability of patients.


Asunto(s)
Neoplasias , Autocuidado , Humanos , Catéteres , Neoplasias/tratamiento farmacológico , Ditiotreitol , Liberación de Fármacos
9.
Biosensors (Basel) ; 13(6)2023 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-37366979

RESUMEN

Contamination of food by pathogens can pose a serious risk to health. Therefore, monitoring for the presence of pathogens is critical to identify and regulate microbiological contamination of food. In this work, an aptasensor based on a thickness shear mode acoustic method (TSM) with dissipation monitoring was developed to detect and quantify Staphylococcus aureus directly in whole UHT cow's milk. The frequency variation and dissipation data demonstrated the correct immobilization of the components. The analysis of viscoelastic properties suggests that DNA aptamers bind to the surface in a non-dense manner, which favors the binding with bacteria. The aptasensor demonstrated high sensitivity and was able to detect S. aureus in milk with a 33 CFU/mL limit of detection. Analysis was successful in milk due to the sensor's antifouling properties, which is based on 3-dithiothreitol propanoic acid (DTTCOOH) antifouling thiol linker. Compared to bare and modified (dithiothreitol (DTT), 11-mercaptoundecanoic acid (MUA), and 1-undecanethiol (UDT)) quartz crystals, the sensitivity of the sensor's antifouling in milk improved by about 82-96%. The excellent sensitivity and ability to detect and quantify S. aureus in whole UHT cow's milk demonstrates that the system is applicable for rapid and efficient analysis of milk safety.


Asunto(s)
Aptámeros de Nucleótidos , Incrustaciones Biológicas , Técnicas Biosensibles , Animales , Bovinos , Femenino , Staphylococcus aureus , Leche/química , Incrustaciones Biológicas/prevención & control , Ditiotreitol/análisis , Alérgenos/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Límite de Detección
10.
J Hazard Mater ; 456: 131693, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37245366

RESUMEN

Metals in particulate matter (PM) are hypothesized to have enhanced toxicity based on their ability to catalyze reactive oxygen species (ROS) formation. Acellular assays are used to measure the oxidative potential (OP) of PM and its individual components. Many OP assays, including the dithiothreitol (DTT) assay, use a phosphate buffer matrix to simulate biological conditions (pH 7.4 and 37 °C). Prior work from our group observed transition metal precipitation in the DTT assay, consistent with thermodynamic equilibria. In this study, we characterized the effects of metal precipitation on OP measured by the DTT assay. Metal precipitation was affected by aqueous metal concentrations, ionic strength, and phosphate concentrations in ambient PM sampled in Baltimore, MD and a standard PM sample (NIST SRM-1648a, Urban Particulate Matter). Critically, differences in metal precipitation induced differing OP responses of the DTT assay as a function of phosphate concentration in all PM samples analyzed. These results indicate that comparison of DTT assay results obtained at differing phosphate buffer concentrations is highly problematic. Further, these results have implications for other chemical and biological assays that use phosphate buffer for pH control and their use to infer PM toxicity.


Asunto(s)
Contaminantes Atmosféricos , Artefactos , Ditiotreitol , Material Particulado/análisis , Oxidación-Reducción , Estrés Oxidativo , Agua , Bioensayo , Metales , Contaminantes Atmosféricos/análisis
11.
J Clin Lab Anal ; 37(8): e24891, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37161608

RESUMEN

BACKGROUND: It is advised to pretreat the reagent erythrocytes with Dithiothreitol (DTT) to denature the surface CD38 to prevent anti-CD38 monoclonal antibodies (MoAb) from interfering with the blood compatibility test. Anti-CD38 has little impact on the Polybrene test, but it is still unknown how sensitive it is to detect irregular antibodies and how effective it is when compared to the standard DTT-based method. METHODS: Twenty-one patients receiving daratumumab (N = 13) and isatuximab (N = 8) had their serum collected. Standard anti-sera (anti-c, D, E, Fyb , Jka , M, Mia ) with serial dilution were added to patients' serum. Antibody screening tests were performed simultaneously using the manual polybrene method (MP) and DTT-pretreated, automatic indirect antiglobulin test (DTT-IAT) to compare the detection sensitivity. These two methods' operating times and costs were also analyzed. RESULTS: Both MP and DTT-IAT can overcome the interference caused by anti-CD38 MoAb. However, MP is more sensitive in detecting anti-M and anti-Mia and is comparable to DTT-IAT in detecting other antibodies. In terms of cost and operating time, MP is also far superior to DTT-IAT. CONCLUSION: MP is a cost-effective alternative to DTT-IAT in resolving anti-CD38 interference and is especially suitable for populations with a high prevalence of anti-M and anti-Mia . However, both methods have a well-known drawback of low detection sensitivity for anti-K, and K-units should be provided to patients to prevent hemolytic transfusion reactions.


Asunto(s)
Pruebas Hematológicas , Bromuro de Hexadimetrina , Humanos , Prueba de Coombs , Ditiotreitol , Eritrocitos
12.
Drug Metab Dispos ; 51(6): 764-770, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37012073

RESUMEN

Human aldehyde oxidase (hAOX1) is a molybdoflavoenzyme that belongs to the xanthine oxidase (XO) family. hAOX1 is involved in phase I drug metabolism, but its physiologic role is not fully understood to date, and preclinical studies consistently underestimated hAOX1 clearance. In the present work, we report an unexpected effect of the common sulfhydryl-containing reducing agents, e.g., dithiothreitol (DTT), on the activity of hAOX1 and mouse aldehyde oxidases. We demonstrate that this effect is due to the reactivity of the sulfido ligand bound at the molybdenum cofactor with the sulfhydryl groups. The sulfido ligand coordinated to the Mo atom in the XO family of enzymes plays a crucial role in the catalytic cycle and its removal results in the total inactivation of these enzymes. Because liver cytosols, S9 fractions, and hepatocytes are commonly used to screen the drug candidates for hAOX1, our study suggests that DTT treatment of these samples should be avoided, otherwise false negative results by an inactivated hAOX1 might be obtained. SIGNIFICANCE STATEMENT: This work characterizes the inactivation of human aldehyde oxidase (hAOX1) by sulfhydryl-containing agents and identifies the site of inactivation. The role of dithiothreitol in the inhibition of hAOX1 should be considered for the preparation of hAOX1-containing fractions for pharmacological studies on drug metabolism and drug clearance.


Asunto(s)
Aldehído Oxidasa , Sustancias Reductoras , Humanos , Animales , Ratones , Aldehído Oxidasa/metabolismo , Ligandos , Ditiotreitol/farmacología , Coenzimas , Xantina Oxidasa
13.
Toxicology ; 488: 153484, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36878351

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) are persistent in the environment and may disrupt the endocrine system. Our previous study showed that perfluorooctanoic acid (PFOA, C8) and perfluorooctanesulfonic acid (PFOS, C8S) can inhibit 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2) activity leading to an active glucocorticoid accumulation. In this study, we extended investigation for 17 PFAS, including carboxylic and sulfonic acids, with different carbon-chain lengths, to determine their inhibitory potency and structure-activity relationship in human placental and rat renal 11ß-HSD2. C8-C14 PFAS at 100 µM significantly inhibited human 11ß-HSD2 with a potency as C10 (half-maximal inhibitory concentration, IC50, 9.19 µM) > C11 (15.09 µM) > C12 (18.43 µM) > C9 (20.93 µM) > C13 (124 µM) > C14 (147.3 µM) > other C4-C7 carboxylic acids, and C8S > C7S = C10S > other sulfonic acids. For rat 11ß-HSD2, only C9 and C10 and C7S and C8S PFAS exhibited significant inhibitory effects. PFAS are primarily mixed/competitive inhibitors of human 11ß-HSD2. Preincubation and simultaneous incubation with the reducing agent dithiothreitol significantly increased human 11ß-HSD2 but not rat 11ß-HSD2, and preincubation but not simultaneous incubation with dithiothreitol partially reversed C10-mediated inhibition on human 11ß-HSD2. Docking analysis showed that all PFAS bound to the steroid-binding site and carbon-chain length determined the potency of inhibition, with the optimal molecular length (12.6 Å) for potent inhibitors PFDA and PFOS, which is comparable to the molecular length (12.7 Å) of the substrate cortisol. The length between 8.9 and 17.2 Å is the probable threshold molecular length to inhibit human 11ß-HSD2. In conclusion, the carbon-chain length determines the inhibitory effect of PFAS on human and rat 11ß-HSD2, and the inhibitory potency of long-chain PFAS on human and rat 11ß-HSD2 showed V-shaped pattern. Long-chain PFAS may partially act on the cysteine residues of human 11ß-HSD2.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2 , Fluorocarburos , Animales , Femenino , Humanos , Embarazo , Ratas , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasas/metabolismo , Ditiotreitol , Fluorocarburos/toxicidad , Placenta/metabolismo , Relación Estructura-Actividad
14.
Hematology ; 28(1): 2186037, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36892250

RESUMEN

OBJECTIVE: Use red blood cell stabilizer to store the antibody screening and antibody identification reagent red blood cells (RBCs) treated with 0.01 mol/L DTT and investigate its value in the pre-transfusion examinations of patients treated with daratumumab. METHOD: Determined the optimal incubation time for the 0.01 mol/L DTT-treated RBCs method by evaluating the effect of treatment at different time points. Added ID-CellStab to store DTT-treated RBCs, determined the maximum shelf life of reagent RBCs by monitoring the hemolysis index, and assessed changes in the antigenicity of blood group antigens on the surface of RBCs during storage with antibody reagents. RESULT: A protocol for long-term storage of reagent red blood cells treated with the 0.01 mol/L DTT method was established. The optimal incubation time was 40-50 min. RBCs could be stored stably for 18 days after adding ID-CellStab. The protocol was able to eliminate pan-agglutination caused by daratumumab, with no significant changes in the antigens of most blood group systems, except for some attenuation of K antigen and Duffy blood group system antigens during the storage period. CONCLUSION: The storage protocol of reagent RBCs based on the 0.01 mol/L DTT method does not affect the detection of most blood group antibodies and retains a certain degree of detection ability for anti-K antibodies, allowing patients treated with daratumumab to quickly perform pre-transfusion examinations, making up for the shortcomings of currently commercial reagent RBCs.


Asunto(s)
Antígenos de Grupos Sanguíneos , Conservación de la Sangre , Ditiotreitol , Eritrocitos , Humanos , Antígenos de Grupos Sanguíneos/metabolismo , Antígenos de Grupos Sanguíneos/farmacología , Ditiotreitol/farmacología , Ditiotreitol/metabolismo , Eritrocitos/efectos de los fármacos
15.
Carbohydr Res ; 524: 108759, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36746019

RESUMEN

Sulfur containing glycosides offer an exciting prospect for inclusion within noncanonical glycan sequences, particularly as enabling probes for chemical glycobiology and for carbohydrate-based therapeutic development. In this context, we required access to 4-thio-d-glucopyranose and sought its chemical synthesis. Unable to isolate this material in homogenous form, we observed instead a thermodynamic preference for interconversion of the pyranose to 4-thio-d-glucofuranose. Accordingly, we present an improved method to access both bis(4-thio-d-glucopyranoside)-4,4'-disulfide and 4-thio-d-glucofuranose from a single precursor, demonstrating that the latter compound can be accessed from the former using a dithiothreitol controlled reduction of the disulfide. The dithiothreitol-mediated interconversion between pyranose (monomer and disulfide) and furanose forms for this thiosugar is monitored by 1H NMR spectroscopy over a 24-h period. Access to these materials will support accessing sulfur-containing mimetics of glucose and derivatives therefrom, such as sugar nucleotides.


Asunto(s)
Carbohidratos , Glucosa , Ditiotreitol , Carbohidratos/química , Monosacáridos , Disulfuros
16.
Int Orthop ; 47(5): 1147-1152, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36810966

RESUMEN

PURPOSE: Synovial fluid cultures of periprosthetic joint infections (PJI) may be limited by bacteria living in the fluids as biofilm-aggregates. The antibiofilm pre-treatment of synovial fluids with dithiotreitol (DTT) could improve bacterial counts and microbiological early stage diagnosis in patients with suspected PJI. METHODS: Synovial fluids collected from 57 subjects, affected by painful total hip or knee replacement, were divided into two aliquots, one pre-treated with DTT and one with normal saline. All samples were plated for microbial counts. Sensitivity of cultural examination and bacterial counts of pre-treated and control samples were then calculated and statistically compared. RESULTS: Dithiothreitol pre-treatment led to a higher number of positive samples, compared to controls (27 vs 19), leading to a statistically significant increase in the sensitivity of the microbiological count examination from 54.3 to 77.1% and in colony-forming units count from 1884 ± 2.129 CFU/mL with saline pre-treatment to 20.442 ± 19.270 with DTT pre-treatment (P = 0.02). CONCLUSIONS: To our knowledge, this is the first report showing the ability of a chemical antibiofilm pre-treatment to increase the sensitivity of microbiological examination in the synovial fluid of patients with peri-prosthetic joint infection. If confirmed by larger studies, this finding may have a significant impact on routine microbiological procedures applied to synovial fluids and brings further support to the key role of bacteria living in biofilm-formed aggregates in joint infections.


Asunto(s)
Artritis Infecciosa , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Infecciones Relacionadas con Prótesis , Humanos , Ditiotreitol , Líquido Sinovial/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Artroplastia de Reemplazo de Rodilla/efectos adversos , Bacterias , Sensibilidad y Especificidad , Artroplastia de Reemplazo de Cadera/efectos adversos , Biomarcadores
17.
Biophys Chem ; 294: 106962, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36716681

RESUMEN

Proteins can transform from their native state to a state having fibrillar aggregates characterized by cross ß sheet structure. The fibrillar aggregates are known as amyloid and have been linked to several disorders. Disulfide bonds in proteins are one of the important factors that determine the propensity of aggregation. Hen Egg White Lysozyme (HEWL) was used by us as a model protein to decipher the role disulfide bonds play in the amyloid fibril formation and fibril morphology by using Dithiothreitol (DTT) as reducing agent at pH 2.7 and pH 7.4. We found that DTT can have different effects on HEWL amyloid depending on pH and the buffer used for preparing the amyloid fibrils. Our studies highlight the critical role of non-native disulfide bonds in amyloidogenesis and how disruption of these bonds can greatly affect the fibrillation process. Overall, these studies throw light on the fibrillation mechanism and can be explored further in designing effective inhibitors against amyloidosis.


Asunto(s)
Amiloide , Muramidasa , Animales , Amiloide/química , Muramidasa/química , Ditiotreitol/farmacología , Proteínas Amiloidogénicas , Concentración de Iones de Hidrógeno , Disulfuros , Pollos/metabolismo , Agregado de Proteínas
18.
Transfusion ; 63(4): 808-816, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36707937

RESUMEN

BACKGROUND: Administration of anti-CD38 antibodies is a state-of-the-art therapy for patients diagnosed with multiple myeloma (MM). However, this treatment frequently leads to pan-agglutination of red blood cells (RBCs) in patients' serological testing making accurate blood typing and timely transfusion of compatible blood a challenging effort. The antigen masking indirect antiglobulin test (AMIAT) is an approach to address this diagnostic challenge. STUDY DESIGN AND METHODS: A new reagent, called DaraEx plus, uses anti-CD38 Fab fragments to mitigate the anti-CD38 antibody interference in serological assays by masking CD38 on the cell surface. Its performance is extensively examined with commercial sera as well as with patient samples, and compared to the current standard method using dithiothreitol (DTT), which denatures the CD38 antigens on test panel erythrocytes. RESULTS: In the Bio-Rad ID System, DaraEx plus effectively mitigated the interference caused by anti-CD38 antibodies in 86% of patient samples tested while DTT was successful in only 68%. Moreover, there was no negative influence on DTT-sensitive blood group systems such as KEL upon DaraEx plus treatment. The agglutination reactions of all tested anti-CD38 antibodies (Daratumumab, Felzartamab, and Isatuximab) were inhibited by DaraEx plus. The treatment was successful only if DaraEx plus was added to the test cells before the sample. Some of the other gel card systems tested showed background reactions with DaraEx plus-treated cells. CONCLUSION: DaraEx plus treatment is straightforward and quick to perform. In the Bio-Rad ID System, it is superior to DTT treatment in the prevention of anti-CD38 antibody interference.


Asunto(s)
Transfusión Sanguínea , Mieloma Múltiple , Humanos , Transfusión Sanguínea/métodos , Tipificación y Pruebas Cruzadas Sanguíneas , Eritrocitos/metabolismo , Prueba de Coombs , Pruebas de Aglutinación , Ditiotreitol/farmacología , Ditiotreitol/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , ADP-Ribosil Ciclasa 1/metabolismo
19.
Food Chem ; 399: 133964, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36029675

RESUMEN

We employed dithiothreitol (DTT) to reassemble soy lipophilic protein (LP) and increased its solubility for encapsulating resveratrol (Res); we subsequently added hydroxypropyl methylcellulose (HPMC) to further stabilize Res. Physicochemical characterization, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and spectral analysis revealed that DTT triggered the breakage and reassembly of the disulfide bond. Consequently, the solubility of LP increased from 38.64 % to 71.49 %, and the number of free sulfhydryl groups increased to 7.84 mol·g-1. Furthermore, the encapsulation efficiency and structure of reassembled LP nanoparticles loaded with Res were found to be closely related to the DTT concentration used for induction. When HPMC was added, the LP-Res complex demonstrated spontaneous self-assembly, and the pH and temperature stability of the Res in the nanoparticles improved. An in vitro digestion simulation revealed that the reassembled LP was an efficient carrier for Res delivery. Particularly, HPMC improved the bioavailability and sustained release of Res.


Asunto(s)
Ditiotreitol , Derivados de la Hipromelosa , Nanopartículas , Resveratrol , Proteínas de Soja , Derivados de la Hipromelosa/química , Nanopartículas/química , Solubilidad , Proteínas de Soja/química , Glycine max
20.
Drug Chem Toxicol ; 46(3): 413-422, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35266429

RESUMEN

Emamectin benzoate (EMB) is an avermectin insecticide that is extensively used for pest control, but there are few reports concerning its cytotoxic effects on human lymphocytes. In the current study, the hematotoxicity of EMB was evaluated in Molt-4 T-cells, a human T-lymphoblastic cell line with high motility, and the role of vitamin E (VitE) and dithiothreitol (DTT) in attenuating EMB cytotoxicity was characterized. Exposure of Molt-4 cells to EMB decreased cell viability and proliferation, induced a loss of cell clusters, and significantly increased membrane collapse and chromatin condensation. Moreover, EMB significantly increased cell death and suppressed transglutaminase activity. EMB treatment modulated the NF-κB signaling pathway, decreased the expression of p105, p50, and p65/RelA in cytosolic and nuclear fractions, and increased nuclear IκBα expression. EMB increased oxidative stress, as demonstrated by a significant increase in the levels of reactive oxygen species (ROS). Treatment with non-cytotoxic concentrations of VitE or DTT ameliorated the hematotoxicity induced by pretreatment with EMB, increased Molt-4 cell viability, raised the IC50 values of EMB, limited intracellular ROS generation, and mitigated EMB-mediated effects on NF-κB signaling. The results indicate the potential cytotoxicity of EMB on human lymphocytes, and demonstrate that VitE and DTT treatment can reduce the cytotoxic effects of EMB.


Asunto(s)
Ditiotreitol , Ivermectina , FN-kappa B , Linfocitos T , Vitamina E , Humanos , Ditiotreitol/farmacología , Ivermectina/análogos & derivados , Ivermectina/toxicidad , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo , Vitamina E/farmacología
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