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1.
Chin Herb Med ; 16(2): 293-300, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38706826

ABSTRACT

Objective: To clear the amounts of the principal active/toxic components in herbs containing aristolochic acids (HCAAs), which are still used as medicine and/or seasoning in many ethnic minority areas of China. Methods: In this study, six major active and toxic components in HCAAs were extracted with ultrasonic extraction. With 6-O-methyl guanosine as internal standard, the target compounds were analyzed qualitatively and quantitatively by using ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) with multiple reaction monitoring-information dependent acquisition-enhanced production ion scanning mode (MRM-IDA-EPI) combined with dynamic background subtraction (DBS) function. Results: The method showed good linearity in the linear range of the six analytes. The limit range of detection was from 0.01 ng/mL to 0.27 ng/mL. All of the detection repeatability, extraction repeatability and accuracy of the method were good. After extraction, the samples remained stable at 15 °C within 24 h. Six analytes were all found in samples except aristolactam (AL) in sample 2, and the contents varied greatly. The contents of these compounds decreased in fruits, leaves and stems of Aristolochia delavayi successively. Conclusion: This method has the advantages of less sample dosage, simple operation, short analysis cycle, high sensitivity, specificity and accuracy. It laid a good foundation for guiding the safety of HCAAs, the in-depth study of pharmacological and toxicological effects and the scientific and standardized processing and compatibility of HCAAs.

2.
J Colloid Interface Sci ; 662: 109-118, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38340510

ABSTRACT

The impact of Indium (In) doping upon the catalytic performance of Pd-Cu/Al2O3 for carbon monoxide preferential oxidation (CO-PROX) in hydrogen (H2) rich atmosphere at low temperature has been studied. A series of catalysts with extremely low palladium (Pd) loading (0.06 wt%) are synthesized by the facile co-impregnation method. When the In/copper (Cu) atomic ratio equals 0.25, Pd-Cu-In0.25/Al2O3 can keep 40% CO conversion and 100% carbon dioxide (CO2) selectivity at least 120 min at 30 °C, which is significantly superior to the catalytic performance of Pd-Cu/Al2O3. The elaborate characterization findings reveal that the added In species to Pd-Cu/Al2O3 causes Indium oxide (In2O3) to generate, which produces the interaction of In2O3 with Pd-Cu/Al2O3, further promoting the dispersion of copper chloride hydroxide (Cu2Cl(OH)3). Moreover, the modification of In facilitates the re-oxidation of Pd0 to Pd+ through reducing the formation of palladium hydride (PdHx) during the CO-PROX reaction. Meanwhile, the addition of In leads to the decrease of Cu+ electron cloud density, making it easier to be oxidized to Cu2+. Collectively, the easy re-oxidation of Pd0 and Cu+ is favorable to fulfill the Wacker cycle between Pd and Cu species, thus improving the catalytic performance for CO-PROX.

3.
Heliyon ; 9(2): e13630, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36865453

ABSTRACT

Ischemic heart disease and myocardial infarction contribute to the leading cause of death in worldwide. The prevention and management of myocardial ischemia/reperfusion (I/R) injury is an essential part of coronary heart disease surgery and is becoming a major clinical problem in the treatment of ischemic heart disease. Nuciferine has potent anti-inflammatory and antioxidative stress effects, but its role in myocardial ischemia-reperfusion (I/R) is unclear. In this study, we found that nuciferine could reduce the myocardial infarct size in a mouse myocardial ischemia-reperfusion model and improve cardiac function. Furthermore, nuciferine could effectively inhibit hypoxia and reoxygenation (H/R) stimulated apoptosis of primary mouse cardiomyocytes. In addition, nuciferine significantly reduced the level of oxidative stress. The peroxisome proliferator-activated receptor gamma (PPAR-γ) inhibitor GW9662 could reverse the protective effect of nuciferine on cardiomyocytes. These results indicate that nuciferine can inhibit the apoptosis of cardiomyocytes by upregulating PPAR-γ and reducing the I/R-induced myocardial injury in mice.

4.
MedComm (2020) ; 4(2): e222, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36845073

ABSTRACT

Protopanaxadiol (PPD) has potential immunomodulatory effects, but the underlying mechanism remains unclear. Here, we explored the potential roles of gut microbiota in the immunity regulation mechanisms of PPD using a cyclophosphamide (CTX)-induced immunosuppression mouse model. Our results showed that a medium dose of PPD (PPD-M, 50 mg/kg) effectively ameliorated the immunosuppression induced by CTX treatment by promoting bone marrow hematopoiesis, increasing the number of splenic T lymphocytes and regulating the secretion of serum immunoglobulins and cytokines. Meanwhile, PPD-M protected against CTX-induced gut microbiota dysbiosis by increasing the relative abundance of Lactobacillus, Oscillospirales, Turicibacter, Coldextribacter, Lachnospiraceae, Dubosiella, and Alloprevotella and reducing the relative abundance of Escherichia-Shigella. Importantly, PPD-M lost the ability to promote bone marrow hematopoiesis and enhance immunity when the gut microbiota was depleted by broad-spectrum antibiotics. Moreover, PPD-M promoted the production of microbiota-derived immune-enhancing metabolites including cucurbitacin C, l-gulonolactone, ceramide, DG, prostaglandin E2 ethanolamide, palmitoyl glucuronide, 9R,10S-epoxy-stearic acid, and 9'-carboxy-gamma-chromanol. KEGG topology analysis showed that the PPD-M treatment significantly enriched the sphingolipid metabolic pathway with ceramide as a main metabolite. Our findings reveal that PPD enhances immunity by manipulating gut microbiota and has the potential to be used as an immunomodulator in cancer chemotherapy.

5.
Pharmacol Res ; 187: 106624, 2023 01.
Article in English | MEDLINE | ID: mdl-36563868

ABSTRACT

Selenium has good antitumor effects in vitro, but the hypoxic microenvironment in solid tumors makes its clinical efficacy unsatisfactory. We hypothesized that the combination with oxygen therapy might improve the treatment efficacy of selenium in hypoxic tumors through the changes of redox environment. In this work, two selenium compounds, Na2SeO3 and CysSeSeCys, were selected to interrogate their therapeutic effects on hepatocellular carcinoma (HCC) under different oxygen levels. In tumor-bearing mice, both selenium compounds significantly inhibited the tumor growth, and combined with oxygen therapy further reduced the tumor volume about 50 %. In vitro HepG2 cell experiments, selenium induced autophagy and delayed apoptosis under hypoxia (1 % O2), while inhibited autophagy and accelerated apoptosis under hyperoxia (60 % O2). We found that, in contrast to hypoxia, the hyperoxic environment facilitated the H2Se, produced by the selenium metabolism in cells, to be rapidly oxidized to generate H2O2, leading to inhibit the expression level of Nrf2 and to increase that of phosphorylation of p38 and MKK4, resulting in inhibiting autophagy and accelerating apoptosis. Once the Nrf2 gene was knocked down, selenium compounds combined with hyperoxia treatment would further activate the MAPK signaling pathway and further increase apoptosis. These findings highlight oxygen can significantly enhance the anti-HCC effect of selenium compounds through regulating the Nrf2 and MAPK signaling pathways, thus providing novel therapeutic strategy for the hypoxic tumors and pave the way for the application of selenium in clinical treatment.


Subject(s)
Carcinoma, Hepatocellular , Hyperoxia , Liver Neoplasms , Selenium Compounds , Selenium , Animals , Mice , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Selenium/pharmacology , Selenium/therapeutic use , Selenium Compounds/metabolism , Selenium Compounds/pharmacology , Selenium Compounds/therapeutic use , Hydrogen Peroxide/pharmacology , Signal Transduction , Apoptosis , Hypoxia , Oxygen , Tumor Microenvironment
6.
Front Microbiol ; 13: 833313, 2022.
Article in English | MEDLINE | ID: mdl-35250949

ABSTRACT

Species in the genus Paenibacillus from special habitats have attracted great attention due to their plant growth-promoting traits. A novel plant growth-promoting rhizobacteria (PGPR) species in the genus Paenibacillus was isolated from spruce forest at the height of 3,150 m in the Qilian Mountains, Gansu province, China. The phylogenetic analysis based on 16S rRNA, rpoB, and nifH gene sequences demonstrated that strain LC-T2 T was affiliated in the genus Paenibacillus and exhibited the highest sequence similarity with Paenibacillus donghaensis KCTC 13049 T (97.4%). Average nucleotide identity (ANIb and ANIm) and digital DNA-DNA hybridization (dDDH) between strain LC-T2 T and P. donghaensis KCTC 13049 T were 72.6, 83.3, and 21.2%, respectively, indicating their genetic differences at the species level. These differences were further verified by polar lipids profiles, major fatty acid contents, and several distinct physiological characteristics. Meanwhile, the draft genome analysis provided insight into the genetic features to support its plant-associated lifestyle and habitat adaptation. Subsequently, the effects of volatile organic compound (VOC) emitted from strain LC-T2 T on the growth of Arabidopsis were evaluated. Application of strain LC-T2 T significantly improved root surface area, root projection area, and root fork numbers by 158.3, 158.3, and 241.2%, respectively, compared to control. Also, the effects of LC-T2 T on the growth of white clover (Trifolium repens L.) were further assessed by pot experiment. Application of LC-T2 T also significantly improved the growth of white clover with root fresh weight increased over three-folds compared to control. Furthermore, the viable bacterial genera of rhizosphere soil were detected in each treatment. The number of genera from LC-T2 T -inoculated rhizosphere soil was 1.7-fold higher than that of control, and some isolates were similar to strain LC-T2 T , indicating that LC-T2 T inoculation was effective in the rhizosphere soil of white clover. Overall, strain LC-T2 T should be attributed to a novel PGPR species within the genus Paenibacillus based on phylogenetic relatedness, genotypic features, and phenotypic and inoculation experiment, for which the name Paenibacillus monticola sp. nov. is proposed.

7.
BMC Cardiovasc Disord ; 21(1): 509, 2021 10 21.
Article in English | MEDLINE | ID: mdl-34674651

ABSTRACT

BACKGROUND: To investigate the risk factors for mortality in patients with acute kidney injury requiring continuous renal replacement therapy (AKI-CRRT) after cardiac surgery. METHODS: In this retrospective study, patients who underwent AKI-CRRT after cardiac surgery in our centre from January 2015 to January 2020 were included. Univariable and multivariable analyses were performed to identify the risk factors for in-hospital mortality. RESULTS: A total of 412 patients were included in our study. Of these, 174 died after AKI-CRRT, and the remaining 238 were included in the survival control group. Multivariable logistic regression analysis revealed that EuroSCORE > 7 (odds ratio [OR], 3.72; 95% confidence interval [CI], 1.92-7.24; p < 0.01), intraoperative bleeding > 1 L (OR, 2.14; 95% CI, 1.19-3.86; p = 0.01) and mechanical ventilation time > 70 h (OR, 5.03; 95% CI, 2.40-10.54; p < 0.01) were independent risk factors for in-hospital mortality in patients who had undergone AKI-CRRT. Our study also found that the use of furosemide after surgery was a protective factor for such patients (odds ratio, 0.48; 95% confidence interval, 0.25-0.92; p = 0.03). CONCLUSIONS: In summary, the mortality of patients with AKI-CRRT after cardiac surgery remains high. The EuroSCORE, intraoperative bleeding and mechanical ventilation time were independent risk factors for in-hospital mortality. Continuous application of furosemide may be associated with a better outcome.


Subject(s)
Acute Kidney Injury/mortality , Cardiac Surgical Procedures/adverse effects , Continuous Renal Replacement Therapy , Postoperative Complications/mortality , Acute Kidney Injury/etiology , Acute Kidney Injury/therapy , Age Factors , Aged , Female , Hospital Mortality , Humans , Intraoperative Complications , Male , Middle Aged , Multivariate Analysis , Postoperative Complications/therapy , Regression Analysis , Respiration, Artificial , Retrospective Studies , Risk Factors
8.
Zhongguo Zhong Yao Za Zhi ; 46(17): 4471-4479, 2021 Sep.
Article in Chinese | MEDLINE | ID: mdl-34581052

ABSTRACT

This study explored the in vivo effects and mechanisms of the modern classical prescription Supplemented Gegen Qinlian Decoction Formula(SGDF) against diabetic kidney disease(DKD). Sixty rats were randomly divided into the normal group, model group, SGDF group, and rosiglitazone(ROS) group. The modified DKD rat model was established by employing the following three methods: exposure to high-fat diet, unilateral nephrectomy, and intraperitoneal injection of streptozotocin(STZ). After modeling, rats in the four groups were treated with double distilled water, SGDF suspension, and ROS suspension, respectively, by gavage every day. At the end of the 6 th week of drug administration, all the rats were sacrificed for collecting urine, blood, and kidney tissue, followed by the examination of rat general conditions, urine and blood biochemical indicators, glomerulosclerosis-related indicators, podocyte pyroptosis markers, insulin resistance(IR)-related indicators, and key molecules in the insulin receptor substrate(IRS) 1/phosphatidylinositol-3-kinase(PI3 K)/serine threonine kinase(Akt) signaling pathway. The results showed that SGDF and ROS improved the general conditions, some renal function indicators and glomerulosclerosis of DKD model rats without affecting the blood glucose(BG). Besides, they ameliorated the expression characteristics and levels of podocyte pyroptosis markers, alleviated IR, and up-regulated the protein expression levels of the key molecules in IRS1/PI3 K/Akt pathway to varying degrees. In conclusion, similar to ROS, SGDF relieves DKD by targeting multiple targets in vivo. Specifically, it exerts the therapeutic effects by alleviating podocyte pyroptosis and IR. This study has preliminarily provided the pharmacological evidence for the research and development of new drugs for the treatment of DKD based on SGDF.


Subject(s)
Diabetes Mellitus , Diabetic Nephropathies , Insulin Resistance , Podocytes , Animals , Diabetic Nephropathies/drug therapy , Drugs, Chinese Herbal , Pyroptosis , Rats
9.
Redox Biol ; 44: 102010, 2021 08.
Article in English | MEDLINE | ID: mdl-34082381

ABSTRACT

Activated microglia are an important type of innate immune cell in the brain, and they secrete inflammatory cytokines into the extracellular milieu, exert neurotoxicity to surrounding neurons and are involved in the pathogenesis of many brain disorders. Quercetin (Qu), a natural flavonoid, is known to have anti-inflammatory and antioxidant properties. Previous studies have shown that both increased reactive oxygen species (ROS) stress and decreased autophagy participate in the activation of microglial. In the current study, we showed that Qu significantly attenuated LPS-induced inflammatory factor production, cell proliferation and NF-κB activation of microglia. Importantly, Qu decreased the levels of NLR family, pyrin domain containing three (NLRP3) inflammasome and pyroptosis-related proteins, including NLRP3, active caspase-1, GSDMD N-terminus and cleaved IL-1ß. Further study indicated that this anti-inflammatory effect of Qu was associated with mitophagy regulation. Importantly, Qu promoted mitophagy to enhance damaged mitochondrial elimination, which then reduced mtROS accumulation and alleviated NLRP3 inflammasome activation. Then, we confirmed that Qu treatment protected primary neurons against LPS-induced microglial toxicity and alleviated neurodegeneration in both depression and PD mouse models. Further IL-1ß administration blunted these neuroprotective effects of Qu in vitro and in vivo. This work illustrated that Qu prevents neuronal injury via inhibition of mtROS-mediated NLRP3 inflammasome activation in microglia through promoting mitophagy, which provides a potential novel therapeutic strategy for neuroinflammation-related diseases.


Subject(s)
Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Animals , Mice , Microglia , Mitophagy , Quercetin , Reactive Oxygen Species
10.
ACS Appl Mater Interfaces ; 12(42): 47526-47538, 2020 Oct 21.
Article in English | MEDLINE | ID: mdl-32946221

ABSTRACT

NiCo-layered double hydroxide (LDH) has attracted increasing attention in recent years for application in supercapacitors (SCs) owing to its high redox activity and intercalating capability. However, the pristine NiCo-LDH is unable to reach theoretical specific capacitance and satisfying rate capability due to the limited electroactive species and a low ion diffusion rate. Here, we demonstrate novel vertically aligned nanosheet arrays of cobalt metal-organic framework (Co-MOF)@CoNiO2 core-shell composites constructed by the in situ grown Co-MOF shell with a uniform and controlled thickness on the CoNiO2 core via a vapor-phase approach. Owing to the intimate contact and synergistic effect between the Co-MOF shell and the CoNiO2 core, the as-synthesized Co-MOF@CoNiO2 displays a high specific capacitance of about 571 F g-1, which is significantly higher than the pristine NiCo-LDH electrode (380 F g-1). Moreover, the capacitive properties of Co-MOF@CoNiO2 can be further boosted to 757.2 F g-1 after cyclic voltammetry oxidation. The easy preparation and high electrochemical performance of the Co-MOF@CoNiO2 composite make it a potential material for SC application. These findings may inspire the exploration and construction of other MOF shell coating metal oxide from various nanostructured LDHs for varied applications. In addition, the as-assembled EO-Co-MOF@CoNiO2/carbon cloth (CC)//activated carbon (AC) device can achieve a high capacitance of 87.67 F g-1. Meanwhile, the asymmetric supercapacitor (ASC) device exhibits a high energy density of 27.4 Wh kg-1 at a power density of 750 W kg-1.

11.
ACS Appl Mater Interfaces ; 12(2): 2591-2600, 2020 Jan 15.
Article in English | MEDLINE | ID: mdl-31865694

ABSTRACT

The development for environmentally friendly energy conversion and storage equipment has given rise to tremendous research efforts as a result of the growing requirements for environmental friendly resources and the rapid consumption of traditional fossil fuel. Herein, a novel hierarchical CoO/NiO-Cu@CuO heterostructure is successfully devised and synthesized. Cobalt/nickel ions are used to generate novel CoO/NiO-doped laminated CuO nanospheres through the facile in situ wet oxidation combined with cation exchange and calcination strategies. As a result, the electrochemical supercapacitance of the as-prepared CoO/NiO-Cu@CuO electrode can reach 875 C cm-2 (2035 mF cm-2), which exhibits much better electrochemical performance compared to other precursor electrodes at a same current density of 2 mA cm-2. Moreover, an excellent rate capacity of 1395 mF cm-2 (50 mA cm-2) can be achieved when measured at a relative high current density; 90.3% of the initial supercapacitance remains even after 5000 cycles. Furthermore, the as-prepared hierarchical hybrid of laminated CoO/NiO-CuO nanospheres in situ generated on three-dimensional (3D) porous Cu foam is applied to prepare a solid-state asymmetric supercapacitor equipment unit. The fabricated equipment unit shows an energy density of 69.3 W h kg-1 at a power density of 1080 W kg-1. Additionally, the commercially applied 2.5 V light-emitting-diode indicator with blue light can be energized for 4 min when two as-fabricated supercapacitor devices are in series connection. The unique hierarchical heterostructure of the novel laminated nanospheres combined with the 3D grid structure brings about the outstanding electrochemical capacitor performances. This strategy for the fabrication of hierarchical heterostructure electrodes could have an enormous potential for high-performance electrochemical equipment.

12.
J Colloid Interface Sci ; 560: 237-246, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31670021

ABSTRACT

A fiber asymmetric supercapacitor system is designed with NiCo-LDH nanoflakes and FeOOH nanosheets anchored on electrochemically activated graphite fibers as positive electrode and negative electrode, respectively. Due to the formation of COMetal bonding, the oxygen-functionalized carbon on electrochemically activated graphite fibers can bind strongly with NiCo-LDH and FeOOH, which assists in establishing the fast electron transfer routes and fluent ion transport avenues. Both NiCo-LDH and FeOOH anchored on electrochemically activated graphite fibers display a high rate performance, 80% and 87.3% of the electric capacity can be reserved with the current density increasing from 2 to 20 A g-1 and 2 to 10 A g-1, respectively, while the NiCo-LDH and FeOOH deposited on untreated graphite fibers can only retain 45% and 40%. The fabricated novel solid-state fiber asymmetric supercapacitor device exhibits an expanded operation potential window of 1.8 V with a maximum energy density (130 W h kg-1) when the power density is 1.8 kW kg-1. Furthermore, a high energy density (81 W h kg-1) is still achieved at a superhigh power density (10.8 kW kg-1). Additionally, a good cycling stability of the solid-state fiber asymmetric supercapacitor can be obtained (90% capacity retention after 10,000 cycles).

13.
Int J Mol Med ; 44(5): 1943-1951, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31573046

ABSTRACT

S­allyl­cysteine sulfoxide (alliin) is the main organosulfur component of garlic and its preparations. The present study aimed to examine the protective effect of alliin on cardiac function and the underlying mechanism in a mouse model of myocardial infarction (MI). Notably, alliin treatment preserved heart function, attenuated the area of infarction in the myocardium of mice and reduced lesions in the myocardium, including cardiomyocyte fibrosis and death. Further mechanistic experiments revealed that alliin inhibited necroptosis but promoted autophagy in vitro and in vivo. Cell viability assays showed that alliin dose­dependently reduced the necroptotic index and inhibited the expression of necroptosis­related receptor­interacting protein 1, receptor­interacting protein 3 and tumor necrosis factor receptor­associated factor 2, whereas the levels of Beclin 1 and microtubule­associated protein 1 light chain 3, which are associated with autophagy, exhibited an opposite trend upon treatment with alliin. In addition, the level of peroxisome proliferator­activated receptor γ was increased by alliin. Collectively, these findings demonstrate that alliin has the potential to protect cardiomyocytes from necroptosis following MI and that this protective effect occurs via the enhancement of autophagy.


Subject(s)
Autophagy/drug effects , Cysteine/analogs & derivatives , Myocardial Infarction/drug therapy , Myocytes, Cardiac/drug effects , Necroptosis/drug effects , Safrole/analogs & derivatives , Animals , Apoptosis/drug effects , Cell Survival/drug effects , Cysteine/pharmacology , Male , Mice , Mice, Inbred C57BL , Myocardial Infarction/metabolism , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Safrole/pharmacology , Signal Transduction/drug effects
14.
Nanoscale ; 11(6): 2812-2822, 2019 Feb 07.
Article in English | MEDLINE | ID: mdl-30675886

ABSTRACT

The introduction of oxygenous functional groups onto graphene can provide additional pseudocapacitance for supercapacitors. However, how to balance the amount of introduced oxygenous functional groups and the reduced electrical conductivity arising from the disruption of the conjugated system remains a big challenge. Here, a controllable strategy is reported to prepare moderately oxidized reduced graphene oxide (MORGO) via an electrochemical oxidation process. The MORGO not only has oxygenous groups with appropriate quantities, but also preserves the highly crystalline structure of the π-π conjugated carbon framework. As a result, the MORGO films showed superior electrochemical properties to the pristine RGO films and other previously reported RGO films. Furthermore, the oxygenous groups and the conductivity of MORGO films can be easily adjusted by controlling the oxidation time. A hierarchical composite of NiCo-layered double hydroxide nanosheet arrays on MORGO films (MORGO/NiCo-LDH) was also constructed via electrochemical deposition to combine the advantages of electric double-layer electrode materials and faradaic electrode materials. The flexible solid-state supercapacitor fabricated with MORGO/NiCo-LDH film electrodes exhibits a high energy density (0.51 mW h cm-3), as well as a long cycle life (88.2% capacitance retention after 10 000 cycles).

15.
ACS Appl Mater Interfaces ; 10(36): 30388-30399, 2018 Sep 12.
Article in English | MEDLINE | ID: mdl-30070464

ABSTRACT

The poor electronic conductivity of MnO x severely limits the practical application as high-performance electrode materials for faradaic pseudocapacitors. Herein, a facile vapor reduction method is demonstrated for the treatment of MnO x with hydrazine hydrate (HH) to improve the electronic conductivity. The HH vapor treatment without annealing process not only introduces oxygen vacancies to form oxygen-deficient MnO x, but also leads to obvious structural transformation from highly aggregated and poorly crystallized MnO x nanorobs and nanoparticles into uniformly orientated and highly crystallized MnO x nanosheets via the Ostwald ripening process. Compared with pristine MnO x on carbon fiber (CF-MnO x), the reduced CF-MnO x exhibits a highly improved specific capacitance of 1130 mF cm-1 (434 F g-1) with excellent rate capability and cycling stability. Our results have shown that the moderate concentration of oxygen vacancies and highly uniform orientation of reduced MnO x endow the electrode with a fast electron and ion transport, respectively. Moreover, a flexible fiber asymmetric supercapacitor (ASC) device with high-energy and power density based on the as-prepared reduced CF-MnO x as a cathode and electrochemically activated graphene oxide on carbon fiber (CF-ArGO) as an anode is fabricated. The MnO x//ArGO ASC device delivers a high volumetric capacitance of 1.9 F cm-3, a maximum energy density of 1.06 mWh cm-3, and a volumetric power density of 371.3 mW cm-3. The present work opens a new way for oxygen vacancy introduction and structural modification of metal oxide as high-performance materials for energy storage applications.

16.
Chem Res Toxicol ; 28(3): 532-40, 2015 Mar 16.
Article in English | MEDLINE | ID: mdl-25650027

ABSTRACT

Sulfur mustard (SM) is a highly reactive alkylation vesicant and cytotoxic agent that has been recognized as an animal and human carcinogen. Although the exact mechanism of toxicology is vague, DNA alkylation seems to be responsible for the triggering of apoptosis. In this study, after male adult Sprague-Dawley rats were cutaneous exposed to a low concentration of SM at parts-per-million levels, their lungs, livers, pancreases, spleens, marrow, and brains were collected at 11 different time points and analyzed. N7-[2-[(2-hydroxyethyl)thio]-ethyl]guanine (N7-HETEG), N3-[2-[(2-hydroxyethyl)thio]-ethyl]adenine (N3-HETEA), and bis[2-(guanin-7-yl)ethyl]sulfide (Bis-G) as the biomarkers for DNA damage were measured in the vital tissues by isotope dilution ultraperformance liquid chromatography tandem mass spectrometry (ID-UPLC-MS/MS). At the same time, general variations and pathological changes were monitored and detected to evaluate the tissue damage. Time- and dose-dependent data showed that SM had strong permeability and reactivity and that three SM-DNA adducts were detected in all investigated tissues only after 10 min after exposure. Obvious dose-dependency was observed except in the brain and pancreas. Most times to peak (tmax) of all three adducts were less than 3 h, while half-lifetimes (t1/2) were less than 24 h. We also suggested that the lipophilic SM can easily pass through the blood-brain barrier and can be stored in the fatty organs. To the best of our knowledge, the abundant adducts in marrow were found and reported for the first time. The surveillance of N7-HETEG in vivo, which was the most abundant adduct, may be the most efficient indicator to validate SM exposure even without any symptoms. Bis-G can be regarded as a biomarker of effect, which is directly related to the extent of damage. The most abundant Bis-G was found in the most sensitive tissues, marrow, spleen, and lung, which is in good accordance with histopathologic results. General variations and pathological changes were evaluated as well. After cutaneous exposure to SM, the body weights of rats heavily decreased in the first 4 days and were inversely proportional to the applied doses, and then recovered at the last experimental day except for those of the rats at the highest dosing level, in which the relative weights of rat spleens were obviously lost. Moreover, we found remarkable histological changes of the lung and skin, such as encephalemia, at the very beginning of the sampling procedure, and plentiful mononuclear cells in marrow appeared 6 h after exposure. The micronucleus test of marrow cells showed that the micronucleus rate had a positively dose-dependent effect.


Subject(s)
Alkylating Agents/toxicity , Carcinogens/toxicity , Mustard Gas/toxicity , Administration, Cutaneous , Alkylating Agents/administration & dosage , Animals , Bone Marrow/metabolism , Brain/metabolism , Carcinogens/administration & dosage , DNA Adducts/metabolism , Liver/metabolism , Lung/drug effects , Lung/metabolism , Lung/pathology , Male , Micronucleus Tests , Mustard Gas/administration & dosage , Pancreas/drug effects , Pancreas/metabolism , Rats, Sprague-Dawley , Skin/drug effects , Skin/pathology , Spleen/drug effects , Spleen/metabolism , Spleen/pathology
17.
Article in English | MEDLINE | ID: mdl-24858262

ABSTRACT

Sulfur mustard (SM) is a classic vesicant agent, which has been greatly employed in several wars or military conflicts. The most lesion mechanism is its strong alkylation of DNAs in vivo. Until now there are four specific DNA adducts of SM identified for further retrospective detection, i.e., N(7)-(2-hydroxyethylthioethyl)-2'-guanine (N(7)-HETEG), bis(2-ethyl-N(7)-guanine)thioether (Bis-G), N(3)-(2-hydroxyethylthioethyl)-2'-adenine (N(3)-HETEA) and O(6)-(2-hydroxyethylthioethyl)-2'-guanine (O(6)-HETEG), respectively. Here, a novel and sensitive method of isotope-dilution ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combining with solid phase extraction was reported for the simultaneous determination of four SM-DNA adducts. A lower limit of detection of 2-5ngL(-1), and a lower limit of quantitation of 5-10ngL(-1) were achieved, respectively, and the recoveries ranged from 87% to 116%. We applied this method in the determination of four SM-DNA adducts in rabbit urine after dermal exposure by SM in three dose levels (2, 5, 15mgkg(-1)), so as to investigate the related metabolic behavior in vivo. For the first time, in SM exposed rabbit urine, our results revealed the relative accumulation abundance of four SM-DNA adducts, i.e., 67.4% for N(7)-HETEG, 22.7% for Bis-G, 9.8% for N(3)-HETEA, 0.1% for O(6)-HETEG, and significant dose and time dependent responses of these SM-DNA adducts. The four adducts were detectable after 8h, afterwards, their contents continuously increased, achieved maximum in the first two or three days and then gradually decreased till the end of one month. Meanwhile, the amounts of SM-DNA adducts were positively correlated with the exposure doses.


Subject(s)
DNA Adducts/urine , Animals , Chromatography, High Pressure Liquid/methods , Guanine/analogs & derivatives , Guanine/analysis , Mustard Gas/administration & dosage , Mustard Gas/analysis , Mustard Gas/chemistry , Rabbits , Sulfhydryl Compounds/analysis , Sulfhydryl Compounds/chemistry , Tandem Mass Spectrometry/methods
18.
Chem Res Toxicol ; 27(4): 490-500, 2014 Apr 21.
Article in English | MEDLINE | ID: mdl-24467472

ABSTRACT

Sulfur mustard (SM) is a highly reactive alkylating vesicant and causes blisters upon contact with skin, eyes, and respiratory organs. It covalently links with DNAs by forming four mono- or cross-link adducts. In this article, the reference standards of SM-DNA adducts and deuterated analogues were first synthesized with simplified procedures containing only one or two steps and using less toxic chemical 2-(2-chloroethylthio)ethanol or nontoxic chemical thiodiglycol as starting materials. A sensitive and high-throughput simultaneous quantification method of N(7)-[2-[(2-hydroxyethyl)thio]-ethyl]guanine (N(7)-HETEG), O(6)-[2-[(2-hydroxyethyl)thio]-ethyl]guanine (O(6)-HETEG), N(3)-[2-[(2-hydroxyethyl)thio]-ethyl]adenine (N(3)-HETEA), and bis[2-(guanin-7-yl)ethyl]sulfide (Bis-G) in the Sprague-Dawley rat derma samples was developed by stable isotope dilution-ultrahigh performance liquid chromatography-tandem mass spectrometry (ID-UPLC-MS/MS) with the aim of revealing the real metabolic behaviors of four adducts. The method was validated, the limit of detection (S/N ratio greater than 10) was 0.01, 0.002, 0.04, and 0.11 fmol on column for N(7)-HETEG, O(6)-HETEG, Bis-G, and N(3)-HETEA, respectively, and the lower limit of quantification (S/N ratio greater than 20) was 0.04, 0.01, 0.12, and 0.33 fmol on column for N(7)-HETEG, O(6)-HETEG, Bis-G, and N(3)-HETEA, respectively. The accuracy of this method was determined to be 76% to 129% (n = 3), and both the interday (n = 6) and intraday (n = 7) precisions were less than 10%. The method was further applied for the quantifications of four adducts in the derma of adult male Sprague-Dawley rats exposed to SM ex vivo and in vivo, and all adducts had time- and dose-effect relationships. To the best of our knowledge, this is the first time that the real presented status of four DNA adducts was simultaneously revealed by the MS-based method, in which Bis-G showed much higher abundance than the result previously reported and N(3)-HETEA showed much less. It should be noted that since the interstrand cross-linked adduct is believed to stall DNA replication and finally induce a double-strand break, the higher abundance of Bis-G is a great indication of a more serious DNA lesion by SM alkylation.


Subject(s)
Chromatography, High Pressure Liquid/methods , DNA Adducts/analysis , DNA/drug effects , Mustard Gas/toxicity , Tandem Mass Spectrometry/methods , Animals , Isotopes , Limit of Detection , Male , Rats , Rats, Sprague-Dawley
19.
Toxicol Rep ; 1: 533-543, 2014.
Article in English | MEDLINE | ID: mdl-28962267

ABSTRACT

In one event, Chinese male individuals accidentally exposed to unknown chemicals and emerged erythema or blisters on contacted organism derma, then hospitalized. To identify the causative agents, blood, urine and exudate samples were collected from the patients during the therapeutic course. Five established liquid chromatography-mass spectrometry (LC-MS) and gas chromatography (GC)-MS methods were employed to analyze the samples. Here, an overall analysis of four types of sulfur mustard biomarkers, including the hydrolysis/oxidation products, ß-lyase metabolites, DNA adducts and hemoglobin adducts, was conducted toward the samples from exposed individuals. The results of all the four types of biomarkers in different biomedical matrices showed high relevance, and verified that this exposure is indeed originated from sulfur mustard. The concentrations of the biomarkers in specimens revealed a good correlation with the severity of the patient's symptom. The concentration-time profile demonstrated that most of the biomarkers quickly achieved maximum at the beginning of the course, and then decreased and kept a detectable level until the 7th day after exposure. The DNA adducts in urine samples still appeared on the 30th day, and the N-terminal valine adducts in hemoglobin could be monitored for over 90 days, which was meaningful for the concurrent study of clinical samples. To the best of our knowledge, this work provides the total analysis and profile of four categories of biomarkers in human specimens for the first time, and the good accordance between concentration and level of burns, between time course and biomarkers will be of great importance for early diagnosis and medical treatment monitoring of sulfur mustard exposure.

20.
J Pharmacol Sci ; 118(4): 433-46, 2012.
Article in English | MEDLINE | ID: mdl-22447300

ABSTRACT

Multi-glycoside, one of the extracted compounds from Tripterygium wilfordii HOOK. f. (GTW), has been shown to be clinically effective in suppressing glomerular inflammation in chronic kidney disease. However, its clinical application is often limited by its cytotoxic actions on the liver. This study was performed to contrast the dose-effects of GTW on glomerular inflammation and hepatic damage in two types of anti-Thy1.1 glomerulonephritis (GN). Rats with acute or chronic anti-Thy1.1 GN were either left untreated (the Vehicle group) or treated with a high or low dose of GTW and sacrificed on day 7 or day 45. GTW was administrated 3 days before or at the same time as the antibody injection and lasted until sacrifice. GTW at high dose ameliorated glomerular macrophage accumulation, mesangial proliferation, proteinuria, and interleukin-2 expression in the acute anti-Thy1.1 GN model, but caused structural and functional lesions in the liver. In contrast, GTW at low dose improved activated macrophage and T lymphocyte infiltration, mesangial injury, proteinuria, and interleukin-2 and interferon-γ expressions without hepatic toxicity in the chronic model of GN induced by anti-Thy1.1 antibody. In conclusion, GTW at low dose not only effectively inhibits glomerular inflammation but also avoids severe injuries to the liver.


Subject(s)
Glomerulonephritis/drug therapy , Glomerulonephritis/pathology , Glycosides/physiology , Inflammation Mediators/physiology , Isoantibodies/toxicity , Liver Diseases/drug therapy , Plant Extracts/administration & dosage , Tripterygium , Animals , Dose-Response Relationship, Immunologic , Female , Glomerulonephritis/immunology , Kidney Glomerulus/drug effects , Kidney Glomerulus/immunology , Kidney Glomerulus/pathology , Liver Diseases/immunology , Liver Diseases/pathology , Plant Extracts/isolation & purification , Plant Extracts/toxicity , Rats , Rats, Wistar , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/pathology , Tripterygium/immunology
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