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1.
Clin Cancer Res ; 30(4): 849-864, 2024 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-37703185

RESUMEN

PURPOSE: Models to study metastatic disease in rare cancers are needed to advance preclinical therapeutics and to gain insight into disease biology. Osteosarcoma is a rare cancer with a complex genomic landscape in which outcomes for patients with metastatic disease are poor. As osteosarcoma genomes are highly heterogeneous, multiple models are needed to fully elucidate key aspects of disease biology and to recapitulate clinically relevant phenotypes. EXPERIMENTAL DESIGN: Matched patient samples, patient-derived xenografts (PDX), and PDX-derived cell lines were comprehensively evaluated using whole-genome sequencing and RNA sequencing. The in vivo metastatic phenotype of the PDX-derived cell lines was characterized in both an intravenous and an orthotopic murine model. As a proof-of-concept study, we tested the preclinical effectiveness of a cyclin-dependent kinase inhibitor on the growth of metastatic tumors in an orthotopic amputation model. RESULTS: PDXs and PDX-derived cell lines largely maintained the expression profiles of the patient from which they were derived despite the emergence of whole-genome duplication in a subset of cell lines. The cell lines were heterogeneous in their metastatic capacity, and heterogeneous tissue tropism was observed in both intravenous and orthotopic models. Single-agent dinaciclib was effective at dramatically reducing the metastatic burden. CONCLUSIONS: The variation in metastasis predilection sites between osteosarcoma PDX-derived cell lines demonstrates their ability to recapitulate the spectrum of the disease observed in patients. We describe here a panel of new osteosarcoma PDX-derived cell lines that we believe will be of wide use to the osteosarcoma research community.


Asunto(s)
Neoplasias Óseas , Óxidos N-Cíclicos , Indolizinas , Osteosarcoma , Compuestos de Piridinio , Humanos , Animales , Ratones , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Ensayos Antitumor por Modelo de Xenoinjerto , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Osteosarcoma/metabolismo , Línea Celular Tumoral , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo
2.
Carbohydr Polym ; 297: 120010, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36184165

RESUMEN

Discovering principles to tune the heat-transport properties of cellulose nanofibril (CNF) films will open the door for the development of biomass-derived heat-transfer materials and break away from existing petroleum-based polymer composites. In this study, we added various multivalent metal ions to CNF films with surface carboxy groups formed by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation and measured their thermal diffusivities in the dry state by an original method to verify the tunability of the thermal diffusivity. We found that the in-plane thermal diffusivity of the film is inversely proportional to the ionic radius and directly proportional to the Pauling electro-negativity. The CNF film with proton-neutralized carboxyl groups showed the highest level of thermal diffusivity among the films with various metal ions. Molecular dynamics simulations clarified that the spatial distribution of the introduced ions is determined by the closest distance between the cation and carboxylate oxygen atom of the TEMPO-oxidized CNF surface.


Asunto(s)
Nanofibras , Petróleo , Celulosa , Óxidos N-Cíclicos , Oxígeno , Polímeros , Protones
3.
Molecules ; 27(14)2022 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-35889433

RESUMEN

The scavenging activity of hydroxyl radicals, produced by the Fenton reaction, is commonly used to quantify the antioxidant capacity of plant extracts. In this study, three Fenton systems (Fe/phosphate buffer, Fe/quinolinic acid and Fe/phosphate buffer/quinolinic acid) and the thermal degradation of peroxydisulfate were used to produce hydroxyl radicals; the hydroxyl radical scavenging activity of plant extracts (ginger, blueberry juices and green tea infusion) and chemical compounds (EGCG and GA) was estimated by spin trapping with DMPO (5,5-dimethyl-1-pyrroline N-oxide) and EPR (Electron Paramagnetic Resonance) spectroscopy. Phosphate buffer was used to mimic the physiological pH of cellular systems, while quinolinic acid (pyridine-2,3-dicarboxylic acid) facilitates the experimental procedure by hindering the spontaneous oxidation of Fe(II). The EC50 (the concentration of chemical compounds or plant extracts which halves the intensity of the DMPO-OH adduct) values were determined in all the systems. The results show that, for both the chemical compounds and the plant extracts, there is not a well-defined order for the EC50 values determined in the four hydroxyl radical generating systems. The interactions of phosphate buffer and quinolinic acid with the antioxidants and with potential iron-coordinating ligands present in the plant extracts can justify the observed differences.


Asunto(s)
Antioxidantes , Radical Hidroxilo , Antioxidantes/farmacología , Óxidos N-Cíclicos , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres , Radical Hidroxilo/química , Fosfatos , Extractos Vegetales , Ácido Quinolínico , Marcadores de Spin
4.
Trials ; 23(1): 196, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35246228

RESUMEN

BACKGROUND: Existing recommended treatment options for personality disorders (PDs) are extensive and costly. There is emerging evidence indicating that trauma-focused treatment using eye movement desensitization and reprocessing (EMDR) therapy aimed at resolving memories of individuals' adverse events can be beneficial for this target group within a relatively short time frame. The primary purpose of the present study is to determine the effectiveness of EMDR therapy versus waiting list in reducing PD symptom severity. Furthermore, the effects of EMDR therapy on trauma symptom severity, loss of diagnosis, personal functioning, quality of life, and mental health outcomes will be determined. In addition, the cost-effectiveness of EMDR therapy in the treatment of PDs is investigated. Moreover, predictors of treatment success, symptom deterioration and treatment discontinuation will be assessed. Lastly, experiences with EMDR therapy will be explored. METHOD: In total, 159 patients with a PD will be included in a large multicentre single-blind randomized controlled trial. The Structured Clinical Interview for DSM-5 Personality Disorders will be used to determine the presence of a PD. Participants will be allocated to either a treatment condition with EMDR therapy (ten biweekly 90-min sessions) or a waiting list. Three months after potential treatment with EMDR therapy, patients can receive treatment as usual for their PD. All participants are subject to single-blinded baseline, post-intervention and 3-, 6- and 12-month follow-up assessments. The primary outcome measures are the Assessment of DSM-IV Personality Disorders and the Clinician-Administered PTSD Scale for DSM-5. For cost-effectiveness, the Treatment Inventory of Costs in Patients with psychiatric disorders, EuroQol-5D-3L, and the Mental Health Quality of Life Questionnaire will be administered. The PTSD Checklist for DSM-5, Brief State Paranoia Checklist and Difficulties in Emotion Regulation Scale will be used to further index trauma symptom severity. Type of trauma is identified at baseline with the Childhood Trauma Questionnaire-SF and Life Events Checklist for the DSM-5. Personal functioning and health outcome are assessed with the Level of Personality Functioning Scale-BF 2.0, Outcome Questionnaire-45 and Mental Health Quality of Life Questionnaire. Experiences with EMDR therapy of patients in the EMDR therapy condition are explored with a semi-structured interview at post-intervention. DISCUSSION: It is expected that the results of this study will contribute to knowledge about the effectiveness, and cost-effectiveness of trauma-focused treatment using EMDR therapy in individuals diagnosed with a PD. Follow-up data provide documentation of long-term effects of EMDR therapy on various outcome variables, most importantly the reduction of PD symptom severity and loss of diagnoses. TRIAL REGISTRATION: Netherlands Trial Register NL9078 . Registered on 31 November 2020.


Asunto(s)
Desensibilización y Reprocesamiento del Movimiento Ocular , Trastornos por Estrés Postraumático , Óxidos N-Cíclicos , Desensibilización y Reprocesamiento del Movimiento Ocular/métodos , Humanos , Estudios Multicéntricos como Asunto , Pacientes Ambulatorios , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/terapia , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple Ciego , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapia , Resultado del Tratamiento
5.
Andrology ; 10(4): 775-788, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35060362

RESUMEN

BACKGROUND: Oxidative stress is one of the leading factors responsible for poor post-thaw semen quality because of overproduction of reactive oxygen species (ROS) over neutralizing antioxidants present in semen. Mainly two ROS generation sites are present in spermatozoa, that is, mitochondria and plasma membrane. Therefore, the idea of targeting these specific sites for minimization of ROS production with the compounds having known mechanism of actions was built up as a core for this research. OBJECTIVE: Present study was done to investigate the effects of Mito TEMPO and acetovanillone individually and in combination on freezability of buffalo spermatozoa. MATERIALS AND METHODS: For the experiment, semen extender was supplemented with Mito TEMPO (50 µM), acetovanillone (50 µM), and a combination of Mito TEMPO + acetovanillone (50 µM+ 50 µM), designated as Group II, Group III, and Group IV, respectively. Control group without any supplementation was designated as Group I. A total of 24 ejaculates with individual progressive motility (IPM) of ≥70% were selected for the study. After final dilution, filling-sealing of straws, equilibration, and freezing were done as per the standard procedure. Semen samples were evaluated for IPM, plasma membrane integrity, lipid peroxidation, total antioxidant capacity (TAC), and cholesterol to phospholipids (C/P) ratio at both fresh and post-thaw stages. Evaluation of ROS, mitochondrial membrane potential (MMP), capacitation status (CTC assay), and in vitro fertility potential were conducted only on frozen-thawed samples. RESULTS: The addition of Mito TEMPO (50 µM) and acetovanillone (50 µM) individually and in combination significantly (p < 0.05) improved post-thaw semen quality in terms of IPM, plasma membrane integrity, TAC, cholesterol content, C/P ratio, MMP, Chlortetracycline (CTC)-Full (F) pattern, and zona binding ability of buffalo spermatozoa, while significantly (p < 0.05) reduced ROS production, lipid peroxidation, and capacitation like changes as compared to the control group. DISCUSSION: As Mito TEMPO acts as an SOD mimetic and also detoxifies ferrous iron at the mitochondria level, it aids in neutralization of excessive ROS production and minimizes oxidative stress-related damages that enhances the antioxidant potential of sperm mitochondria. Earlier studies also indicated improved post-thaw semen quality in 50 µM supplemented group. The improvement observed in acetovanillone (50 µM) group might be because of inhibition of Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase as this enzyme activation by various physical/chemical inducers during cryopreservation process leads to activation of CatSper channel resulting in calcium influx, premature capacitation, and acrosomal reaction like changes through activation of adenylate cyclase and cAMP/PKA-mediated tyrosine phosphorylation of sperm proteins. Acetovanillone also prevents NADPH oxidase-mediated inhibition of glutathione reductase activity, which has a vital role in protecting the structural and functional integrity of sperm plasma membrane. CONCLUSION: Results indicated beneficial effects of supplementation of Mito TEMPO and acetovanillone on sperm freezability and individual supplementation was as efficient as the combination group for sustaining post-thaw semen quality.


Asunto(s)
Preservación de Semen , Semen , Animales , Masculino , Acetofenonas , Antioxidantes/farmacología , Búfalos , Colesterol , Criopreservación/veterinaria , Crioprotectores/farmacología , Óxidos N-Cíclicos , Suplementos Dietéticos , Especies Reactivas de Oxígeno , Análisis de Semen , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
6.
Andrologia ; 54(1): e14299, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34730242

RESUMEN

Cryopreservation is an effective method to spread qualified ram spermatozoa for reproductive goals in different farms, but cryopreservation's shocks reduce sperm quality. This study investigated the efficacy of the new mitochondria-targeted antioxidant Mito-TEMPO on post-thawed quality of spermatozoa in sheep. Collected samples were divided into five groups and after dilution, received different doses of Mito-TEMPO (0, 0.5, 5, 50 and 500 µM), and frozen. Thawed sperm motility parameters, malondialdehyde content, membrane functionality, abnormal morphology, mitochondria activity, acrosome integrity, DNA fragmentation, ROS concentration, viability and apoptotic-like changes, were evaluated. According to the results, Mito-TEMPO (5 and 50 µM) improved (p ≤ 0.05) motility parameters, average path velocity, membrane functionality, mitochondria activity and viability compared with the other groups. Moreover, apoptotic-like changes, lipid peroxidation and ROS concentration were lower (p ≤ 0.05) in groups received 5 and 50 µM Mito-TEMPO. Mito-TEMPO showed no effect (p > 0.05) on sperm acrosome integrity, morphology and DNA fragmentation. In conclusion, Mito-TEMPO as a targeted antioxidant could be an efficient cryo-additive to enhance quality parameters of post-thawed ram semen.


Asunto(s)
Preservación de Semen , Semen , Animales , Criopreservación , Crioprotectores/farmacología , Óxidos N-Cíclicos , Suplementos Dietéticos , Citometría de Flujo , Masculino , Análisis de Semen , Preservación de Semen/veterinaria , Ovinos , Motilidad Espermática , Espermatozoides
7.
Molecules ; 26(23)2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34885820

RESUMEN

Sophora flavescens is a regularly used traditional Chinese medicine. In an attempt to discover adequate active agents, the isoprenoid flavonoids from S. flavescens were further investigated. In this work, two new compounds (1-2, kurarinol A-B) together with 26 known ones (3-28) were isolated and elucidated on the basis of extensive NMR, UV and MS analyses. Furthermore, the antioxidant activity of all constituents was assessed through ABTS, PTIO and DPPH methodologies and also were evaluated for cytotoxic activity by three tumor cell lines (HepG2, A549 and MCF7) and one human normal cell line (LO2 cells). As a result, a multitude of components revealed significant inhibitory activity. In particular, compound 1-2 (kurarinol A-B), two new flavanonols derivatives, exhibited the most potent ABTS inhibitory activity with IC50 of 1.21 µg/mL and 1.81 µg/mL, respectively. Meanwhile, the new compound 1 demonstrated remarkable cytotoxicity against three cancer cells lines with IC50 values ranging from 7.50-10.55 µM but showed little effect on the normal cell. The two new isoprenoid flavonoids could be promising antioxidant and anti-tumor nature agents.


Asunto(s)
Antioxidantes/farmacología , Flavonoides/farmacología , Sophora/química , Terpenos/farmacología , Benzotiazoles/química , Espectroscopía de Resonancia Magnética con Carbono-13 , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Óxidos N-Cíclicos/química , Flavonoides/química , Depuradores de Radicales Libres/química , Humanos , Imidazoles/química , Espectroscopía de Protones por Resonancia Magnética , Ácidos Sulfónicos/química , Terpenos/química
8.
Int J Biol Macromol ; 188: 678-688, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34343590

RESUMEN

As high-efficiency, safe, and low-drug resistant antibacterial agents, silver nanoparticles (AgNPs) have been widely applied in food and biomedicine. AgNPs was prepared using mango peel extract (MPE) as green and cheap reducing agent and stabilizer. In addition, a novel of preservative film material was developed with polylactic acid (PLA) as protective and substrate. AgNPs was characterized by XPS, XRD and TEM, and the size of AgNPs were in the range of 2.5-6.5 nm. The addition of AgNPs improved the mechanical properties of the film and its barrier ability to water vapor and oxygen. The film exhibited excellent antibacterial properties, and the inhibition rate against Escherichia coli and Staphylococcus aureus were above 95%. Furthermore, in terms of safety, the silver migration and cytotoxicity of the film met the relevant standards, and the shelf life of strawberries was significantly extended.


Asunto(s)
Embalaje de Alimentos , Mangifera/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Poliésteres/química , Plata/química , Animales , Compuestos de Bifenilo/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Óxidos N-Cíclicos/química , Escherichia coli/efectos de los fármacos , Fragaria , Humanos , Imidazoles/química , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Espectroscopía de Fotoelectrones , Picratos/química , Plata/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Termogravimetría , Agua/química , Difracción de Rayos X
9.
J Am Chem Soc ; 143(28): 10565-10570, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34232661

RESUMEN

Aerobic alcohol oxidations catalyzed by transition metal salts and aminoxyls are prominent examples of cooperative catalysis. Cu/aminoxyl catalysts have been studied previously and feature "integrated cooperativity", in which CuII and the aminoxyl participate together to mediate alcohol oxidation. Here we investigate a complementary Fe/aminoxyl catalyst system and provide evidence for "serial cooperativity", involving a redox cascade wherein the alcohol is oxidized by an in situ-generated oxoammonium species, which is directly detected in the catalytic reaction mixture by cyclic step chronoamperometry. The mechanistic difference between the Cu- and Fe-based catalysts arises from the use iron(III) nitrate, which initiates a NOx-based redox cycle for oxidation of aminoxyl/hydroxylamine to oxoammonium. The different mechanisms for the Cu- and Fe-based catalyst systems are manifested in different alcohol oxidation chemoselectivity and functional group compatibility.


Asunto(s)
Alcoholes/química , Óxidos N-Cíclicos/química , Compuestos Férricos/química , Nitratos/química , Compuestos de Amonio Cuaternario/síntesis química , Catálisis , Estructura Molecular , Oxidación-Reducción , Compuestos de Amonio Cuaternario/química
10.
J Agric Food Chem ; 69(32): 9034-9042, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34006112

RESUMEN

The free-radical-mediated formation mechanism of polar polymeric triglycerides (TAGs) was derived based on the formation of lipid-derived radicals and the degradation of TAGs in palm oil (PO), rapeseed oil (RO), and sunflower oil (SO). The experimental spectra were simulated by alkoxyl, alkyl, and 5-dimethyl-1-pyrroline N-oxide (DMPO)-oxidized adducts. DMPO-oxidized adducts were the main radical adducts in the initial stage. Then, alkyl radical adducts became the dominating radical adducts after 12 min in PO and RO. The intensity of alkyl radical adducts was the highest in SO. Therefore, based on the bimolecular reaction, polar polymeric TAGs were mainly bonded by -C-O-O-C- in the initial stage and then by -C-C- and -C-O-C- after 30 min. Besides, according to the correlation analysis between the amounts of polar polymeric TAGs and the degradation of TAGs, the main structures of polar polymeric TAGs in PO, RO, and SO were POL-LOP, POL-OOP, and POO-OOP; OLL-LnLO, OLLn-OLnO, OOO-OLO, and OLLn-OOO; and LLL-LLO, LLL-LLL, and OLL-LLO, respectively.


Asunto(s)
Óxidos N-Cíclicos , Aceites de Plantas , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia por Spin del Electrón , Radicales Libres , Marcadores de Spin , Detección de Spin , Triglicéridos
11.
Carbohydr Polym ; 254: 117415, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357899

RESUMEN

Grapefruit peel nanofibrillated cellulose (GNFC) was used as fat substitute in ice cream. GNFC was characterized by TEM, SEM, and XRD. The effects of GNFC on textural profiles, rheological properties, melting resistance, sensory properties, microstructure, and gross energy (GE) of ice cream were investigated. The results showed that GNFC was short rod-shaped crystal. Ice cream added with GNFC exhibited elastic-dominated behavior and better textural properties. The sensory evaluation score reached the highest level with desirable three-dimensional network structure at 0.4 % GNFC addition. GE of ice cream significantly decreased with reducing fat with maximal reduction rate of 17.90 %. Furthermore, the results of in vitro simulated digestion showed that GNFC addition and fat reduction significantly inhibited fat digestibility of ice cream due to coalescence of fat droplets on GNFC. This study provides new sustainable perspectives for the application of GNFC prepared from agricultural waste as fat substitute in food products.


Asunto(s)
Celulosa/química , Citrus paradisi/química , Sustitutos de Grasa/química , Helados , Nanofibras/química , Nanopartículas/química , Extractos Vegetales/química , Celulosa/farmacología , Óxidos N-Cíclicos/química , Digestión/efectos de los fármacos , Elasticidad , Sustitutos de Grasa/farmacología , Ácidos Grasos no Esterificados/química , Manipulación de Alimentos/métodos , Congelación , Jugo Gástrico/química , Jugo Gástrico/efectos de los fármacos , Concentración de Iones de Hidrógeno , Leucina/química , Extractos Vegetales/farmacología , Reología/métodos , Gusto
12.
Food Chem ; 341(Pt 2): 128227, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33068849

RESUMEN

Different studies have shown that detection of free radicals by ESR spin trapping provides useful information on the susceptibility to oxidation of bulk oils and accordingly on the oxidative stability of different samples for comparative purposes. With the same goal, ESR spin trapping was evaluated in this work for in situ detection of radicals in dried microencapsulated oils (DMOs). By testing different oils, encapsulation matrices and oxidation conditions, results showed that ESR spin trapping can be useful to evaluate the oxidative susceptibility of DMOs, but ESR data should be interpreted cautiously, as the great complexity of the reactions involved may lead to data misinterpretations. Conditions for oxygen availability can have important impacts on the rates of both spin trapping and spin-adduct quenching affecting the levels of radicals observed. The kinetics of oxidation, spin trapping and spin-adduct decay should be known first in bulk oils for correct data interpretation in DMOs.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/métodos , Radicales Libres/análisis , Peroxidación de Lípido/fisiología , Aceites de Plantas/química , Óxidos N-Cíclicos , Desecación , Oxígeno/química , Marcadores de Spin
13.
Cryobiology ; 98: 215-218, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33152325

RESUMEN

Supplementation of cooling medium with some antioxidants could be a helpful way to improve sperm quality during chilling process. The current study was aimed to assess the influence of using Mito-TEMPO in cooling medium on quality parameters and reproductive performance of sheep semen during chilling process. In this study, diluted semen samples were assigned into 5 parts, and received 0, 0.5, 5, 50 and 500 µM Mito-TEMPO. The prepared samples were stored at 5 °C up to 48 h. Chilled sperm motility, viability, abnormal morphology, mitochondrial membrane potential, membrane functionality and malondialdehyde concentration were assessed during 0, 24 and 48 h. For evaluation of reproductive performance, artificial insemination was performed via 24 h-chilled semen. In results, at time 0, no difference was observed among groups. Using 5 and 50 µM Mito-TEMPO resulted in higher (P ≤ 0.05) cooled sperm total motility, progressive motility, membrane functionality, viability and lower malondialdehyde concentration than the other groups during 24 and 48 h storage. The rate of mitochondrial membrane potential was greater (P ≤ 0.05) in treated groups with 5, 50 and 500 µM Mito-TEMPO. Pregnancy, parturition and lambing rates were higher (P ≤ 0.05) when ewes were inseminated with 24 h-chilled semen samples containing 5 and 50 µM Mito-TEMPO compared to the control group. Therefore, supplementation of cooling medium with Mito-TEMPO (5 and 50 µM) could be an efficient method to improve the quality and reproductive efficiency of ram's cooled semen during storage period.


Asunto(s)
Preservación de Semen , Semen , Animales , Criopreservación/métodos , Óxidos N-Cíclicos , Suplementos Dietéticos , Femenino , Masculino , Embarazo , Preservación de Semen/veterinaria , Ovinos , Motilidad Espermática , Espermatozoides
14.
Sci Rep ; 10(1): 14150, 2020 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-32843666

RESUMEN

We herein report the synthesis, antioxidant power and neuroprotective properties of nine homo-bis-nitrones HBNs 1-9 as alpha-phenyl-N-tert-butylnitrone (PBN) analogues for stroke therapy. In vitro neuroprotection studies of HBNs 1-9 against Oligomycin A/Rotenone and in an oxygen-glucose-deprivation model of ischemia in human neuroblastoma cell cultures, indicate that (1Z,1'Z)-1,1'-(1,3-phenylene)bis(N-benzylmethanimine oxide) (HBN6) is a potent neuroprotective agent that prevents the decrease in neuronal metabolic activity (EC50 = 1.24 ± 0.39 µM) as well as necrotic and apoptotic cell death. HBN6 shows strong hydroxyl radical scavenger power (81%), and capacity to decrease superoxide production in human neuroblastoma cell cultures (maximal activity = 95.8 ± 3.6%), values significantly superior to the neuroprotective and antioxidant properties of the parent PBN. The higher neuroprotective ability of HBN6 has been rationalized by means of Density Functional Theory calculations. Calculated physicochemical and ADME properties confirmed HBN6 as a hit-agent showing suitable drug-like properties. Finally, the contribution of HBN6 to brain damage prevention was confirmed in a permanent MCAO setting by assessing infarct volume outcome 48 h after stroke in drug administered experimental animals, which provides evidence of a significant reduction of the brain lesion size and strongly suggests that HBN6 is a potential neuroprotective agent against stroke.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Óxidos N-Cíclicos/química , Depuradores de Radicales Libres/uso terapéutico , Neuronas/efectos de los fármacos , Neuroprotección/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Óxidos de Nitrógeno/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Isquemia Encefálica/inducido químicamente , Línea Celular Tumoral , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Depuradores de Radicales Libres/síntesis química , Depuradores de Radicales Libres/farmacología , Glucosa/farmacología , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Peroxidación de Lípido/efectos de los fármacos , Inhibidores de la Lipooxigenasa/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Neuroblastoma/patología , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/farmacología , Óxidos de Nitrógeno/síntesis química , Óxidos de Nitrógeno/farmacología , Oligomicinas/toxicidad , Oxígeno/farmacología , Rotenona/toxicidad
15.
Sci Rep ; 10(1): 12240, 2020 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-32699288

RESUMEN

Tea plant often suffers from low temperature induced damage during its growth. How to improve the cold resistance of tea plant is an urgent problem to be solved. Nitric oxide (NO), γ-aminobutyric acid (GABA) and proline have been proved that can improve the cold resistance of tea plants, and signal transfer and biosynthesis link between them may enhance their function. NO is an important gas signal material in plant growth, but our understanding of the effects of NO on the GABA shunt, proline and NO biosynthesis are limited. In this study, the tea roots were treated with a NO donor (SNAP), NO scavenger (PTIO), and NO synthase inhibitor (L-NNA). SNAP could improve activities of arginine decarboxylase, ornithine decarboxylase, glutamate decarboxylase, GABA transaminase and Δ1-pyrroline-5-carboxylate synthetase and the expression level of related genes during the treatments. The contents of putrescine and spermidine under SNAP treatment were 45.3% and 37.3% higher compared to control at 24 h, and the spermine content under PTIO treatment were 57.6% lower compare to control at 12 h. Accumulation of proline of SNAP and L-NNA treatments was 52.2% and 43.2% higher than control at 48 h, indicating other pathway of NO biosynthesis in tea roots. In addition, the NO accelerated the consumption of GABA during cold storage. These facts indicate that NO enhanced the cold tolerance of tea, which might regulate the metabolism of the GABA shunt and of proline, associated with NO biosynthesis.


Asunto(s)
Camellia sinensis/metabolismo , Óxido Nítrico/metabolismo , Raíces de Plantas/metabolismo , Poliaminas/metabolismo , Prolina/metabolismo , Té/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Carboxiliasas/metabolismo , Frío , Respuesta al Choque por Frío/fisiología , Óxidos N-Cíclicos/metabolismo , Glutamato Descarboxilasa/metabolismo , Imidazoles/metabolismo , Donantes de Óxido Nítrico/metabolismo , Ornitina Descarboxilasa/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Putrescina/metabolismo , S-Nitroso-N-Acetilpenicilamina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo
16.
J Vasc Res ; 57(5): 261-275, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32554967

RESUMEN

BACKGROUND: Oxidative stress plays an essential role in the vascular tone in hypertension; however, the mechanisms remain unclear. AIM: This study aimed to determine the antioxidant effect of tempol and vitamin C (Vit-C) on the basal tone and vascular remodeling of the aorta in nitric oxide (NO) deficiency-induced hypertensive rats. METHOD: Male Sprague-Dawley rats were induced to hypertension by Nω-nitro-L-arginine methyl ester (L-NAME). Animals were randomized as follows: vehicle (Control: CR), CR-tempol, CR-Vit-C, L-NAME, L-NAME-tempol, and L-NAME-Vit-C. After 6 weeks of treatment, the basal aortic tone was evaluated by sodium nitroprusside (SNP) and calcium-free medium. Endothelial function, NO, reduced-to-oxidized glutathione (GSH/GSSG) ratio, resting membrane potential (mP), and vascular remodeling were also measured. RESULTS: L-NAME rats showed an increased basal tone that was blunted by both SNP (-547 ± 69; n = 7 vs. CR: -7.5 ± 6.7 mg; n = 7; p < 0.001) and calcium-free medium. Tempol or Vit-C did not reverse hypertension, and the high basal tone was decreased only with tempol. In L-NAME rats, only tempol partially improved endothelial function, GSH-to-GSSG ratio, mP values, and vascular remodeling. CONCLUSIONS: Tempol decreased calcium-dependent basal aortic tone and improved vascular homeostasis in L-NAME rats. Vit-C did not lead to a similar effect, suggesting that alterations in the superoxide dismutase pathway may play a role in the basal aortic tone.


Asunto(s)
Antioxidantes/farmacología , Aorta Torácica/efectos de los fármacos , Ácido Ascórbico/farmacología , Óxidos N-Cíclicos/farmacología , Suplementos Dietéticos , Hipertensión/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Remodelación Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Animales , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatología , Modelos Animales de Enfermedad , Glutatión/metabolismo , Hipertensión/inducido químicamente , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Potenciales de la Membrana/efectos de los fármacos , NG-Nitroarginina Metil Éster , Óxido Nítrico/metabolismo , Oxidación-Reducción , Ratas Sprague-Dawley , Marcadores de Spin
17.
Hypertension ; 76(1): 101-112, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32520619

RESUMEN

Age-related vascular endothelial dysfunction is a major antecedent to cardiovascular diseases. We investigated whether increased circulating levels of the gut microbiome-generated metabolite trimethylamine-N-oxide induces endothelial dysfunction with aging. In healthy humans, plasma trimethylamine-N-oxide was higher in middle-aged/older (64±7 years) versus young (22±2 years) adults (6.5±0.7 versus 1.6±0.2 µmol/L) and inversely related to brachial artery flow-mediated dilation (r2=0.29, P<0.00001). In young mice, 6 months of dietary supplementation with trimethylamine-N-oxide induced an aging-like impairment in carotid artery endothelium-dependent dilation to acetylcholine versus control feeding (peak dilation: 79±3% versus 95±3%, P<0.01). This impairment was accompanied by increased vascular nitrotyrosine, a marker of oxidative stress, and reversed by the superoxide dismutase mimetic 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl. Trimethylamine-N-oxide supplementation also reduced activation of endothelial nitric oxide synthase and impaired nitric oxide-mediated dilation, as assessed with the nitric oxide synthase inhibitor L-NAME (NG-nitro-L-arginine methyl ester). Acute incubation of carotid arteries with trimethylamine-N-oxide recapitulated these events. Next, treatment with 3,3-dimethyl-1-butanol for 8 to 10 weeks to suppress trimethylamine-N-oxide selectively improved endothelium-dependent dilation in old mice to young levels (peak: 90±2%) by normalizing vascular superoxide production, restoring nitric oxide-mediated dilation, and ameliorating superoxide-related suppression of endothelium-dependent dilation. Lastly, among healthy middle-aged/older adults, higher plasma trimethylamine-N-oxide was associated with greater nitrotyrosine abundance in biopsied endothelial cells, and infusion of the antioxidant ascorbic acid restored flow-mediated dilation to young levels, indicating tonic oxidative stress-related suppression of endothelial function with higher circulating trimethylamine-N-oxide. Using multiple experimental approaches in mice and humans, we demonstrate a clear role of trimethylamine-N-oxide in promoting age-related endothelial dysfunction via oxidative stress, which may have implications for prevention of cardiovascular diseases.


Asunto(s)
Envejecimiento/fisiología , Endotelio Vascular/efectos de los fármacos , Metilaminas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Acetilcolina/farmacología , Adolescente , Adulto , Anciano , Envejecimiento/sangre , Animales , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Arteria Braquial/efectos de los fármacos , Arteria Braquial/fisiología , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/fisiología , Óxidos N-Cíclicos/farmacología , Suplementos Dietéticos , Microbioma Gastrointestinal , Humanos , Metilaminas/administración & dosificación , Metilaminas/sangre , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico Sintasa de Tipo III/metabolismo , Marcadores de Spin , Superóxidos/metabolismo , Tirosina/análogos & derivados , Tirosina/sangre , Vasodilatación/efectos de los fármacos , Vasodilatación/fisiología , Adulto Joven
18.
Carbohydr Polym ; 236: 115999, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172833

RESUMEN

Cellulose nanofibers (CNFs) from kelp were prepared by cellulase treatment with lengths greater than 3 µm. CNFs were further oxidized by TEMPO-oxidized system, and the lengths of the oxidized CNFs (TEMPO-CNFs) were 0.6-1 µm. AFM and TEM images showed that intertwined CNFs fibers were divided into individual nanofibrils. The crystallinity of TEMPO-CNFs increased to 66.5 %. TGA analysis indicated that TEMPO-CNFs were more sensitive to temperature than cellulose and CNFs. FT-IR spectra revealed no changes in the basic cellulose structures of CNFs and TEMPO-CNFs. In the sunflower oil/water (20/80, v/v) model emulsions, the oil droplet sizes were less than 20 µm in CNFs emulsions, which became smaller in TEMPO-CNFs emulsions. Delamination was found in CNFs emulsions after three days of storage. Addition of NaCl increased the volumes of TEMPO-CNFs emulsions but enlarged the oil droplets sizes. TEMPO-CNFs emulsions had the largest volume with smallest and most homogeneous oil droplets at pH 3. TEMPO-CNFs emulsions showed good stability after storage for 30 days. Further, TEMPO-CNFs could also emulsify 50 % (v/v) of sunflower oil. All these results indicated that TEMPO-CNFs can be used in preparing Pickering emulsions.


Asunto(s)
Celulosa Oxidada/química , Emulsiones/química , Kelp/química , Laminaria/química , Nanofibras/química , Óxidos N-Cíclicos/química , Tamaño de la Partícula , Aceite de Girasol/química
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117702, 2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-31748160

RESUMEN

In this paper, a unique water-soluble heptamethine cyanine dye as NIR photosensitizer was synthesized to explore its properties associated with potential applications in photodynamic therapy (PDT). In the strategy of designing this photosensitizer, a sulfonic acid was used as a water soluble functional group and linked to the fluorophore through alkyl chains. 4-amino-2,2,6,6-tetramethylpiperidine-N-oxyl(Tempo) moiety was used as the a nitroxide spin label in obtaining biochemical reaction information in vivo due to it could greatly increase the inter-system crossing (ISC) process for triplet-state photosensitizers and low toxicity. As expected, the photosensitizers performed well in vitro photodynamic therapy. There were a remarkable absorbance band located at 692 nm and emission peaks falls at 762 nm, the quantum yield (Φf) was calculated to be 12.12% in pure aqueous solution using ICG as standards. The photosensitizer also has high singlet oxygen quantum yield (Φ△) for 16.96% with NIR LED irradiation. This photosensitizer can rapidly produce singlet oxygen and exhibit high phototoxicity under NIR light irradiation. It has excellent cellular uptake ability and better cell compatibility. It was also successfully applied in Near-infrared fluorescence imaging and AO/EB staining. In a whole, the organic dye based on Heptamethine cyanine used as photosensitizer has great potential in vivo cancer treatment.


Asunto(s)
Carbocianinas/uso terapéutico , Colorantes/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Espectroscopía Infrarroja Corta , Agua/química , Carbocianinas/síntesis química , Carbocianinas/química , Línea Celular Tumoral , Óxidos N-Cíclicos/química , Oscuridad , Humanos , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/química , Oxígeno Singlete/química , Solubilidad , Espectrometría de Fluorescencia , Coloración y Etiquetado
20.
Int J Biol Macromol ; 137: 1278-1285, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31271795

RESUMEN

Three types of nanocellulose, namely nano-fibrilated cellulose (NFC, also called cellulose nano-fibrils (CNF)), TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical) oxidized cellulose nano-fibrils (TEMPO-CNF), and nano-crystalline cellulose (NCC, also called cellulose nano-crystals (CNC)), were studied in terms of their effects on in vitro milk digestion and mineral adsorption. The effects of anionic NC (TEMPO-CNF and CNC) on in vitro starch digestion and glucose diffusion were also investigated. Results show that TEMPO-CNF and CNC at high concentrations caused significant reductions in glucose diffusion, especially at 0.36% (w/w) TEMPO-CNF and 2-4% (w/w) CNC. In addition, CNF and TEMPO-CNF at 0.30% (w/w) significantly reduced the amount of free fatty acid produced during intestinal digestion of milk fat. CNC at a concentration of 0.3% (w/w) delayed diffusion of free amino nitrogen during intestinal digestion of milk protein. All three types of NC adsorbed significant amount of Fe, and CNC adsorbed significant amount of Zn, while no significant adsorption was observed on other minerals (Ca, Mg, Zn, Cu and Ag). Results from this study suggest that all three types of NC, when incorporated in food or supplements as zero-calorie fiber, may affect food digestion and nutrient absorption.


Asunto(s)
Celulosa/química , Digestión , Leche/química , Leche/metabolismo , Minerales/química , Almidón/química , Almidón/metabolismo , Adsorción , Animales , Óxidos N-Cíclicos/química , Difusión , Tracto Gastrointestinal/metabolismo , Glucosa/química , Nitrógeno/química , Reología
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