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1.
ACS Appl Mater Interfaces ; 15(50): 58356-58366, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38054241

ABSTRACT

Sodium-ion batteries (SIBs) suffer from limited ion diffusion and structural expansion, generating the urgent demand for Na+ accommodable materials with promising architectures. In this work, the rational exploration for Co4S3 nanoparticles confined in an MnS nanorod-grafted N, S-codoped carbon polyhedron (Co-Mn-S@N-S-C) is achieved by the in situ growth of MOF on MnO2 nanorod along with the subsequent carbonization and sulfurization. Benefiting from the distinctive nanostructure, the Co-Mn-S@N-S-C anode delivers excellent structural stability, resulting in prolonged cycling stability with a capacity retention of 90.2% after 1000 cycles at 2 A g-1. Moreover, the reaction storage mechanism is clarified by the in situ X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements. The results indicate that properly designed electrode materials have huge potential applications for highly efficient energy storage devices.

2.
Nano Lett ; 23(12): 5762-5769, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37310729

ABSTRACT

Lithium-sulfur batteries (LSBs) are known to be potential next-generation energy storage devices. Recently, our group reported an LSB cathode made using sulfur spheres that has been spherically templated by MXene nanosheets decorated with CoSe2 nanoparticles, forming a "loose-templating" configuration. It was postulated that the minimal restacking of the outer nanoparticle-decorated MXene layer helps to enable facile ionic transport. However, as the nanosheets do not adhere conformally to the internal sphere's surface, such a configuration can be controversial, thus requiring a more systematic understanding. In this work, we report and quantify for the first time the independent and dependent variables involved in this morphology, allowing us to identify that having smaller nanoparticles resulted in better Li+ ion transport and enhanced electrochemical performances. The optimized cathode structure exhibited an initial specific capacity of 1274 mAh/g and a 0.06% decay rate per cycle at 0.5 C over 1000 cycles in LSBs.

3.
ACS Appl Mater Interfaces ; 15(22): 26650-26659, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37226049

ABSTRACT

The rational design of advanced catalysts for sodium-sulfur (Na-S) batteries is important but remains challenging due to the limited understanding of sulfur catalytic mechanisms. Here, we propose an efficient sulfur host consisting of atomic low-coordinated Zn-N2 sites dispersed on N-rich microporous graphene (Zn-N2@NG), which realizes state-of-the-art sodium-storage performance with a high sulfur content of 66 wt %, high-rate capability (467 mA h g-1 at 5 A g-1), and long cycling stability for 6500 cycles with an ultralow capacity decay rate of 0.0062% per cycle. Ex situ methods combined with theoretical calculations demonstrate the superior bidirectional catalysis of Zn-N2 sites on sulfur conversion (S8 ↔ Na2S). Furthermore, in situ transmission electron microscopy was applied to visualize the microscopic S redox evolution under the catalysis of Zn-N2 sites without liquid electrolytes. During the sodiation process, both surface S nanoparticles and S molecules in the mircopores of Zn-N2@NG quickly convert into Na2S nanograins. During the following desodiation process, only a small part of the above Na2S can be oxidized into Na2Sx. These results reveal that, without liquid electrolytes, Na2S is difficult to be decomposed even with the assistance of Zn-N2 sites. This conclusion emphasizes the critical role of liquid electrolytes in the catalytic oxidation of Na2S, which was usually ignored by previous works.

4.
ACS Appl Mater Interfaces ; 15(16): 20064-20074, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37043701

ABSTRACT

Lithium-sulfur (Li-S) batteries have shown exceptional theoretical energy densities, making them a promising candidate for next-generation energy storage systems. However, their practical application is limited by several challenging issues, such as uncontrollable Li dendrite growth, sluggish electrochemical kinetics, and the shuttling effect of lithium polysulfides (LiPSs). To overcome these issues, we designed and synthesized hierarchical matrixes on carbon cloth (CC) by using metal-organic frameworks (MOFs). ZnO nanosheet arrays were used as anode hosts (CC-ZnO) to enable stable Li plating and stripping. The symmetric cell with CC-ZnO@Li was demonstrated to have enhanced cycling stability, with a voltage hysteresis of ∼25 mV for over 800 h at 1 mA cm-2 and 1 mAh cm-2. To address the cathode challenges, we developed a multifunctional CC-NC-Co cathode host with physical confinement, chemical anchoring, and excellent electrocatalysis. The full cells with CC-ZnO@Li anodes and CC-NC-Co@S cathodes exhibited excellent electrochemical performance, with long cycling life (0.02% and 0.03% capacity decay per cycle when cycling 900 times at 0.5 C and 600 times at 1 C, respectively) and outstanding rate performance (793 mAh g-1 at 4 C). Additionally, the pouch cell based on the flexible CC-ZnO@Li anode and CC-NC-Co@S cathode showed good stability in different bending states. Overall, our study presents an effective strategy for preparing flexible Li and S hosts with hierarchical structures derived from MOF, which can pave the way for high-performance Li-S batteries.

5.
Nano Lett ; 22(21): 8679-8687, 2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36315106

ABSTRACT

Two-dimensional MXenes produce competitive performances when incorporated into lithium-sulfur batteries (LSBs), solving key problems such as the poor electronic conductivity of sulfur and dissolution of its polysulfide intermediates. However, MXene nanosheets are known to easily aggregate and restack during electrode fabrication, filtration, or water removal, limiting their practical applicability. Furthermore, in complex electrocatalytic reactions like the multistep sulfur reduction process in LSBs, MXene alone is insufficient to ensure an optimal reaction pathway. In this work, we demonstrate for the first time a loose templating of sulfur spheres using Ti3C2Tx MXene nanosheets decorated with polymorphic CoSe2 nanoparticles. This work shows that the templating of sulfur spheres using nanoparticle-decorated MXene nanosheets can prevent nanosheet aggregation and exert a strong electrocatalytic effect, thereby enabling improved reaction kinetics and battery performance. The S@MXene-CoSe2 cathode demonstrated a long cycle life of 1000 cycles and a low capacity decay rate of 0.06% per cycle in LSBs.

6.
Small ; 17(35): e2101728, 2021 09.
Article in English | MEDLINE | ID: mdl-34278715

ABSTRACT

Zinc metal is an ideal candidate for aqueous rechargeable batteries due to its high theoretical capacity and natural abundance. However, its commercialization is inevitably challenged by several critical factors such as dendrite growth and parasitic side-reactions, leading to low coulombic efficiency and a limited lifespan. Herein, a modified Zn foil with a zincophilic ZnSe layer deposited by a simple selenization process is proposed. An order of magnitude stronger adsorption capability toward Zn2+ ions and uniform ion diffusion tunnels of ZnSe enables lower nucleation energy barrier and faster ion-diffusion kinetics. Meanwhile, detrimental Zn corrosion in aqueous system is also effectively mitigated. As a result, ZnSe@Zn anode shows reversible Zn plating/stripping (1700 h at 1 mA cm-2 ) with ultra-low voltage hysteresis (41 mV), contributing to exceptional cycling stability over 500 cycles with negligible capacity fading for the ZnSe@Zn/MnO2 full cell.


Subject(s)
Manganese Compounds , Zinc , Electrodes , Oxides
7.
ACS Nano ; 15(5): 8507-8516, 2021 May 25.
Article in English | MEDLINE | ID: mdl-33900061

ABSTRACT

Zinc sulfide (ZnS) exhibits promise in sodium-ion batteries (SIBs) because of its low operation voltage and high theoretical specific capacity. However, pristine ZnS is not adequate in realizing rapid and robust sodium storage owing to its low reversibility, poor structure stability, and sluggish kinetics. To date, most efforts focus on utilizing carbonaceous incorporation to improve its electrochemical performances. Nevertheless, it remains an arduous challenge for realizing superior rate capability while obtaining stable cycling. Herein, inspired by the crystal structure of hexagonal ZnIn2S4, which possesses an intrinsic layered feature with larger unit-cell volume versus that of ZnS, indium incorporation is thus deployed as an immediate remedy. In/ex situ investigations combined with density functional theory calculations are conducted to reveal the superior kinetics, high reversibility, and good structure stability of ZnIn2S4. Notably, the formed indium-based derivatives during cycling manifest a Na+ (de)intercalation process, thereby exciting a synergetic mechanism to stabilize electrochemical cycling. As a result, the electrochemical performances of Zn-based sulfide are significantly improved via the indium incorporation. Furthermore, a full cell based on the ZnIn2S4 anode with the superior electrochemical performance is developed. This work provides an effective tactic of heteroatom incorporation for optimizing structure as well as exciting a complementary reaction process toward developing superior anodes for high-performance alkali-ion batteries.

8.
Nanoscale ; 12(20): 10964-10971, 2020 May 28.
Article in English | MEDLINE | ID: mdl-32419003

ABSTRACT

The electrochemical method can directly convert N2 into the high-value-added NH3 under ambient conditions and is considered to be a green and sustainable alternative to the traditional Haber-Bosch process. However, the electrochemical nitrogen reduction reaction (NRR) suffers from a low ammonia yield rate over the reported electrocatalysts. Herein, we have developed a general strategy to boost the NRR performance, enabled by the metallic 1T phase dominated transition metal dichalcogenide quantum dots (TMD QDs). Impressively, the obtained MoSe2 QDs achieved a superior ammonia yield rate of 340 µg mg-1 cat. h-1 with excellent ammonia generation sustainability. Experimental and theoretical studies revealed that the excellent catalytic activity of MoSe2 QDs mainly originates from the ultra-small quantized size (high surface area and high-density active edge/defect sites) and high-percentage metallic 1T phase (the N2 adsorption on the 1T phase is spontaneous, and the energy barrier of the potential determining step on the 1T phase is very low). Most importantly, our concept is universal for TMD materials (i.e., MoS2, WSe2, WS2 and NbSe2) that also exhibit a much-enhanced ammonia yield rate as compared to other electrocatalysts.

9.
Adv Sci (Weinh) ; 8(1): 2002722, 2020 Jan.
Article in English | MEDLINE | ID: mdl-33437582

ABSTRACT

Zinc-ion batteries (ZIBs) have attracted intensive attention due to the low cost, high safety, and abundant resources. However, up to date, challenges still exist in searching for cathode materials with high working potential, excellent electrochemical activity, and good structural stability. To address these challenges, microstructure engineering has been widely investigated to modulate the physical properties of cathode materials, and thus boosts the electrochemical performances of ZIBs. Here, the recent research efforts on the microstructural engineering of various ZIB cathode materials are mainly focused upon, including composition and crystal structure selection, crystal defect engineering, interlayer engineering, and morphology design. The dependency of cathode performance on aqueous electrolyte for ZIB is further discussed. Finally, future perspectives and challenges on microstructure engineering of cathode materials for ZIBs are provided. It is aimed to provide a deep understanding of the microstructure engineering effect on Zn2+ storage performance.

10.
ChemSusChem ; 13(6): 1379-1391, 2020 Mar 20.
Article in English | MEDLINE | ID: mdl-31821700

ABSTRACT

Lamellar molybdenum disulfide (MoS2 ) has attracted a wide range of research interests in recent years because of its two-dimensional layered structure, ultrathin thickness, large interlayer distance, adjustable band gap, and capability to form different crystal structures. These special characteristics and high anisotropy have made MoS2 widely applicable in energy storage and harvesting. In this Minireview, a systematic and comprehensive introduction to MoS2 , as well as its composites, is presented. It is aimed to summarize the various synthetic methods of MoS2 -based composites and their application in energy-storage devices (lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, and supercapacitors) in detail. Based on recent studies, this Minireview provides important and comprehensive guidelines for further study and development efforts in the MoS2 in energy-storage field.

11.
Med Sci Monit ; 24: 7119-7129, 2018 Oct 06.
Article in English | MEDLINE | ID: mdl-30291716

ABSTRACT

BACKGROUND This study aimed to discover the common cause of non-variceal upper-gastrointestinal bleeding (NVUGIB) by conducting a multi-center retrospective study from 2008 to 2012. MATERIAL AND METHODS Hospitalized patients ages ≥18 years old, from 8 hospitals in China, diagnosed with NVUGIB by endoscopy from 1 January 2008 to 31 December 2012 were enrolled. Questionnaires were developed and a data-entry graphical user interface was designed by using EpiData software. RESULTS Total of 2977 hospitalized patients from 8 medical centers were included. A total of 95.47% (2842/2977) of patients were admitted to a general ward, 3.53% (105/2977) were admitted to an emergency ward, and 1.00% (31/2977) were admitted to an intensive care unit. Peptic ulcer remained the most common cause of NVUGIB (73.26%), but there was a declining trend in its constituent ratio, from 2008 to 2012. A total of 14.41% (429/2977) of patients had co-morbid conditions, 92.85% (2764/2977) used proton-pump inhibitors (PPIs) prior to endoscopic treatment, 19.65% (585/2977) underwent emergency endoscopy, and 23.45% (698/2977) received a transfusion of red blood cell suspensions. A total of 5.34% (159/2977) underwent endoscopic therapy, with a treatment rate of 16.9% in high-risk peptic ulcer patients (96/568). A total of 7.69% (237/2977) were administered aspirin, of whom 32.50% (77/237) resumed aspirin intake after gastrointestinal bleeding was controlled. The median length of hospitalization was 8 days (IQR, 5-11) and the mortality rate was 1.71% (51/2977). CONCLUSIONS Peptic ulcer was still the most common cause of NVUGIB in China. The proportion of patients with high-risk peptic ulcer bleeding who received endoscopic therapy was 16.9%. Only 19.65% of NVUGIB patients underwent emergency endoscopy.


Subject(s)
Peptic Ulcer Hemorrhage/etiology , Peptic Ulcer/complications , Adult , Aged , China , Endoscopy, Gastrointestinal/methods , Female , Gastrointestinal Hemorrhage/etiology , Humans , Male , Middle Aged , Retrospective Studies , Upper Gastrointestinal Tract/blood supply
12.
Sci Rep ; 8(1): 9334, 2018 06 19.
Article in English | MEDLINE | ID: mdl-29921870

ABSTRACT

Nesfatin-1, a satiety molecule processed from nucleobindin2 (NUCB2), is implicated in visceral hypersensitivity in rats and colocalized with 5-hydroxytryptamine (5-HT) in the dorsal raphe nucleus (DRN). Maternal separation (MS) in rats contributes to visceral hypersensitivity via elevated expression of 5-HT in the DRN. Intracerebroventricular injection of nesfatin-1 activates DRN 5-HT neurons. In this study, A model of visceral hypersensitivity was developed by subjecting rats to MS. Colorectal distension was used to detect visceral sensitivity, which was evaluated by abdominal withdrawal reflex (AWR) scores and electromyogram (EMG) magnitude. MS rats exhibited higher AWR scores and EMG magnitude compared with controls. The numbers of nesfatin-1- and tryptophan hydroxylase (TPH, the rate-limiting enzyme for 5-HT synthesis)-positive cells in the DRN were significantly elevated accordingly. Visceral hypersensitivity was significantly alleviated in MS rats treated with intra-DRN administration of anti-nesfatin-1/NUCB2, accompanied by decreased expression of 5-HT and TPH in the DRN, compared with the vehicle-treated group. In contrast, intra-DRN administration of nesfatin-1 into normal adult rats induced visceral hypersensitivity, which correlated with elevated expression of 5-HT and TPH in the DRN. In conclusion, Nesfatin-1 has critical effects on visceral hypersensitivity; the underlying mechanisms might be related to the activation of DRN 5-HT neurons.


Subject(s)
Calcium-Binding Proteins/metabolism , DNA-Binding Proteins/metabolism , Dorsal Raphe Nucleus/metabolism , Nerve Tissue Proteins/metabolism , Neurons/metabolism , Serotonin/metabolism , Animals , Electromyography , Female , Immunohistochemistry , Male , Nucleobindins , Pregnancy , Rats , Tryptophan Hydroxylase/metabolism
13.
Zhongguo Zhong Yao Za Zhi ; 42(20): 3974-3982, 2017 Oct.
Article in Chinese | MEDLINE | ID: mdl-29243436

ABSTRACT

The present study was designed to evaluate the cardioprotective effect of latifolin on pituitrin(Pit) or isoproterenol(ISO)-induced myocardial injury in rats, and further investigate its underlying mechanisms. Rats were administrated sublingually with pituitrin or subcutaneously with isoproterenol to induce acute myocardial ischemia in rats, and lead II electrocardiograph was recorded. In rats with isoproterenol, ELISA assay or colorimetric method was used to detect the content or activity of myocardial injury markers in serum, and the SOD activity and MDA content in myocardium were detected by colorimetric assay; histopathological examination was conducted by HE staining; the frozen section of myocardial tissues was used for DCFH-DA fluorescent staining to detect the content of ROS in myocardium; Western blot was used to detect the protein expression levels of Nrf2, Keap1, HO-1 and NQO1 in myocardium. Results showed that latifolin significantly inhibited ST-segment changes induced by pituitrin or isoproterenol, and increased heart rate. Further mechanism study showed that latifolin reduced cardiac troponin I(cTnI) level, aspartate transaminase(AST) and lactate dehydrogenase(LDH) activities in serum, increased myocardial superoxide dismutase(SOD) activity and reduced myocardial malondialdehyde(MDA) level, and protected myocardium with less necrosis, infiltration of inflammatory cells and fracture of myocardial fibers. Furthermore, latifolin obviously reduced ROS level in myocardium, inhibited the expression of Kelch-like ECH-associated protein-1(Keap1), increased the nuclear translocation of nuclear factor erythroid 2 related factor 2(Nrf2), and promoted the expression of Heme oxygenase-1(HO-1) and NAD(P)H quinone oxidoreductase-1 (NQO1) in myocardial tissues. Our data suggest that latifolin has a potent protective effect against pituitrin or isoproterenol-induced myocardial injury, which may be related to inhibition of oxidative stress by activating Nrf2 signaling pathway.


Subject(s)
Dalbergia/chemistry , Myocardial Ischemia/drug therapy , NF-E2-Related Factor 2/metabolism , Phenols/pharmacology , Animals , Heme Oxygenase (Decyclizing)/metabolism , Malondialdehyde/metabolism , Myocardial Ischemia/chemically induced , NAD(P)H Dehydrogenase (Quinone)/metabolism , Oxidative Stress , Rats , Reactive Oxygen Species/metabolism , Signal Transduction , Superoxide Dismutase/metabolism
14.
Soft Matter ; 11(28): 5727-37, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26083487

ABSTRACT

A series of chiral aryl amide compounds bearing peptide pendants have been investigated as low molecular weight gelators. A mechanistic study reveals that complementary hydrogen bonding from peptide pendants is the main driving force for the formation of organogels. This new class of organogels can exhibit multi-stimuli-responsive behavior upon applying (1) thermal, (2) pH, (3) enantiomeric purity, and (4) fluoride anion stimuli. Enantiomeric purity as a new external stimulus displays sensitive stimuli-responsiveness; only 0.02 equiv. of the enantiomer can completely disassemble the gel aggregate. They will serve as excellent smart materials with potential applications in chiral sensors, recognition, and separation.


Subject(s)
Amides/chemistry , Gels/chemistry , Peptides/chemistry , Hydrogen Bonding , Stereoisomerism
15.
World J Gastroenterol ; 20(37): 13521-9, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-25309082

ABSTRACT

AIM: To investigate the role of epidermal growth factor (EGF) in visceral hypersensitivity and its effect on the serotonin transporter (SERT). METHODS: A rat model for visceral hypersensitivity was established by intra-colonic infusion of 0.5% acetic acid in 10-d-old Sprague-Dawley rats. The visceral sensitivity was assessed by observing the abdominal withdrawal reflex and recording electromyographic activity of the external oblique muscle in response to colorectal distension. An enzyme-linked immunosorbent assay was used to measure the EGF levels in plasma and colonic tissues. SERT mRNA expression was detected by real-time PCR while protein level was determined by Western blot. The correlation between EGF and SERT levels in colon tissues was analyzed by Pearson's correlation analysis. SERT function was examined by tritiated serotonin (5-HT) uptake experiments. Rat intestinal epithelial cells (IEC-6) were used to examine the EGF regulatory effect on SERT expression and function via the EGF receptor (EGFR). RESULTS: EGF levels were significantly lower in the rats with visceral hypersensitivity as measured in plasma (2.639 ± 0.107 ng/mL vs 4.066 ± 0.573 ng/mL, P < 0.01) and in colonic tissue (3.244 ± 0.135 ng/100 mg vs 3.582 ± 0.197 ng/100 mg colon tissue, P < 0.01) compared with controls. Moreover, the EGF levels were positively correlated with SERT levels (r = 0.820, P < 0.01). EGF displayed dose- and time-dependent increased SERT gene expressions in IEC-6 cells. An EGFR kinase inhibitor inhibited the effect of EGF on SERT gene upregulation. SERT activity was enhanced following treatment with EGF (592.908 ± 31.515 fmol/min per milligram vs 316.789 ± 85.652 fmol/min per milligram protein, P < 0.05) and blocked by the EGFR kinase inhibitor in IEC-6 cells (590.274 ± 25.954 fmol/min per milligram vs 367.834 ± 120.307 fmol/min per milligram protein, P < 0.05). CONCLUSION: A decrease in EGF levels may contribute to the formation of visceral hypersensitivity through downregulation of SERT-mediated 5-HT uptake into enterocytes.


Subject(s)
Epidermal Growth Factor/metabolism , Hyperalgesia/metabolism , Intestinal Mucosa/metabolism , Irritable Bowel Syndrome/metabolism , Pain Threshold , Serotonin Plasma Membrane Transport Proteins/metabolism , Visceral Pain/metabolism , Acetic Acid , Animals , Cell Line , Disease Models, Animal , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Epidermal Growth Factor/blood , Epidermal Growth Factor/pharmacology , Epithelial Cells/metabolism , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , Gene Expression Regulation , Hyperalgesia/chemically induced , Hyperalgesia/genetics , Hyperalgesia/physiopathology , Intestines/drug effects , Intestines/innervation , Irritable Bowel Syndrome/chemically induced , Irritable Bowel Syndrome/genetics , Irritable Bowel Syndrome/physiopathology , Male , Pain Threshold/drug effects , RNA, Messenger/metabolism , Rats, Sprague-Dawley , Serotonin Plasma Membrane Transport Proteins/genetics , Signal Transduction , Time Factors , Visceral Pain/chemically induced , Visceral Pain/genetics , Visceral Pain/physiopathology
16.
Mol Biol Rep ; 41(12): 8303-17, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25218841

ABSTRACT

This study aimed to identify gene expression profile in the rat brain resulting from acute alcohol intoxication (AAI). Eighteen SD rats were divided into the alcohol-treated group (n = 9) and saline control group (n = 9). Periorbital blood samples were taken to determine their blood alcohol content by gas chromatography. Tissue sections were analyzed by H and E staining and biochemical assays. Real-time reverse transcription PCR was used to validate microarray data. Statistical analysis was carried out using SPSS18.0 software (Version 18.0, SPSS Inc., Chicago, IL, USA). H and E staining demonstrated that alcohol-treated rats showed no obvious pathological changes in nerve cells compared with those in the control group. Biochemical tests revealed that alcohol-treated rats had lower superoxide dismutase activity than those in the control group (167.3 ± 10.3 U/mg vs. 189.2 ± 5.9 U/mg, P < 0.05). Furthermore, the malondialdehyde levels in alcohol-treated rats were higher than those in the control group (3.48 ± 0.24 mmol/mg vs. 2.51 ± 0.23 mmol/mg, P < 0.05). Microarray data presented 366 up-regulated genes and 300 down-regulated genes in the AAI rat brain. Gene ontology analysis identified 31 genes up-regulated and 39 down-regulated among all differentially expressed genes. Twenty-four pathways showed significant differences, including 12 pathways involved with up-regulated genes and 12 pathways involved with down-regulated genes. Selected genes showed significantly different expression in both alcohol-treated and control groups (P < 0.05). Gene expression analysis enabled clustering of alcohol intoxication-related genes by function. These genes expression may be potential targets for treatment or drug screening for acute alcohol intoxication.


Subject(s)
Hydrogen-Ion Concentration
17.
Cent Eur J Immunol ; 39(2): 152-8, 2014.
Article in English | MEDLINE | ID: mdl-26155116

ABSTRACT

To evaluated the effect and mechanism of leflunomide (LEF) in murine model of collage-induced arthritis (CIA) on modulating the balance of Th17/Treg cells. DBA mice were divided into: control, CIA, CIA + LEF and CIA + Ibuprofen group. After 14 days immunization with bovine type II collagen (CII), except control group, mice were orally administered saline (CIA group), LEF or ibuprofen daily for 14 days. The severity of arthritis joint was assessed by using arthritis score. The numbers of CD3 + CD4 + interleukin 17 (IL-17) + Th17 cells and CD4 + CD25 + Foxp3+ Tregs were determined by flow cytometry, the expression of ROR-γt, Foxp3 and IL-21 mRNA in spleen were quantified by RT-PCR and IL-17, IL-21 and transforming growth factor ß (TGF-ß) level in serum was measured by ELISA. In comparison with CIA group, CIA + LEF and CIA + Ibuprofen group reduced the disease severity obviously (p < 0.05). Leflunomide reduced Th17 cells, the expression of ROR-γt and IL-21 mRNA (p < 0.05) and the levels of IL-17 and IL-21 in serum. In addition, Ibuprofen but not LEF has effect on Treg cells number, Foxp3 mRNA expression and TGF-ß secretion. These results indicate that LEF effect on the balance od Th17/Treg through suppressing Th17 cells, but not stimulating Treg cells. Leflunomide may act as a potential immunomodulator for the treatment of rheumatoid arthritis (RA).

18.
Zhonghua Yi Xue Za Zhi ; 93(30): 2388-91, 2013 Aug 13.
Article in Chinese | MEDLINE | ID: mdl-24300209

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of submucosal tunneling endoscopic resection (STER) in the treatment of middle and lower esophagus submucosal tumors (SMT) originating from muscularis propria (MP) layer. METHODS: A total number of 33 esophagus submucosal tumor (SMT) originating from MP layer underwent tumor resection by STER after endoscopic ultrasonography (EUS) and CT examination at Endoscopy Center, Department of Gastroenterology, First Affiliated Hospital, Nanjing Medical University from March 2012 to March 2013. There were 17 males and 16 females with an age range of (50 ± 10) years. Their lesion size, lesion origin, pathology, operative duration and complication rate were analyzed. RESULTS: Among them, the origins were of submucosal (n = 4, 12.1%), superficial muscularis propria layer (SMP) (n = 18, 54.6%), deep muscularis layer (DMP) (n = 10, 30.3%) and serosa (n = 1, 3.0%). There were single tumor (n = 30, 90.9%), double tumors (n = 2, 6.1%) and triple tumors (n = 1, 3.0%). Except for 1 case of non-resected hemangioma, 36 operative specimens were examined pathologically, including 30 leiomyomas tumors (83.3%), 5 stromal tumors (GIST) (13.9%) and 1 lipoma tumor (2.8%). Thirty-two lesions were successfully resected by STER with a complete resection rate of 97.0%. Average lesion size was (1.7 ± 1.0) cm and average operative duration (49 ± 26) min. A number of (7.8 ± 2.5) hemostatic clips were used to close the mucosal incision site. Subcutaneous emphysema occurred in 3 patients (9.1%) while puncture and pneumothorax developed in one case (3.0%). All of them recovered uneventfully through conservative treatments. CONCLUSIONS: As a new safe, efficacious and feasible treatment for middle and lower esophagus submucosal tumors, STER may completely resect SMT and provide accurate histopathological evaluations. And it is feasible to regain the mucosal integrity of GI tract and prevent the occurrences of leakage and secondary infections.


Subject(s)
Endoscopy, Digestive System/methods , Esophageal Neoplasms/surgery , Mucous Membrane/surgery , Adult , Aged , Esophageal Neoplasms/pathology , Esophagus/pathology , Female , Humans , Male , Middle Aged , Mucous Membrane/pathology , Retrospective Studies , Treatment Outcome , Young Adult
19.
World J Gastroenterol ; 19(22): 3487-93, 2013 Jun 14.
Article in English | MEDLINE | ID: mdl-23801843

ABSTRACT

AIM: To explore the role of nesfatin-1 on irritable bowel syndrome (IBS)-like visceral hypersensitivity. METHODS: The animal model of IBS-like visceral hypersensitivity was induced by intracolonic infusion of 0.5% acetic acid (AA) in saline once daily from postnatal days 8-21. Experiments were performed when rats became adults. The visceral sensitivity of rats was evaluated by abdominal withdrawal reflex (AWR) and electromyographic (EMG) activity of the external oblique muscle to graded colorectal distension. The content of nesfatin-1 in serum was determined using enzyme-linked immunosorbent assay. After implantation of an intracerebroventricular (ICV) cannula and two electrodes into the external oblique muscle, model rats were randomly divided into four groups. Animals then received ICV injection of 8 µg of anti-nesfatin-1/nucleobindin-2 (NUCB2), 50 µg of α-helical corticotropin releasing factor (CRF) 9-41 (non-selective CRF receptor antagonist), 50 µg of NBI-27914 (selective CRF1 receptor antagonist) or 5 µL of vehicle. After 1 h of ICV administration, visceral sensitivity of each group was measured again, and comparisons between groups were made. RESULTS: Rats treated with AA showed higher mean AWR scores and EMG activity at all distension pressures compared with controls (P < 0.05). On histopathologic examination, no evidence of inflammation or abnormalities in structure were noted in the colon of either control or AA-treated groups. Myeloperoxidase values were not significantly different between the two groups. The level of nesfatin-1 in serum was significantly higher in the AA-treated group than in the control group (5.34 ± 0.37 ng/mL vs 4.81 ± 0.42 ng/mL, P < 0.01). Compared with rats injected with vehicle, rats which received ICV anti-nesfatin-1/NUCB2, α-helical CRF9-41 or NBI-27914 showed decreased mean AWR scores and EMG activity at all distension pressures (P < 0.05). CONCLUSION: Nesfatin-1 may be associated with IBS-like visceral hypersensitivity, which may be implicated in brain CRF/CRF1 signaling pathways.


Subject(s)
Abdominal Pain/blood , Behavior, Animal , Calcium-Binding Proteins/blood , Colon/innervation , DNA-Binding Proteins/blood , Irritable Bowel Syndrome/blood , Nerve Tissue Proteins/blood , Pain Perception , Pain Threshold , Abdominal Pain/chemically induced , Abdominal Pain/pathology , Abdominal Pain/physiopathology , Acetic Acid , Animals , Antibodies/administration & dosage , Behavior, Animal/drug effects , Colon/pathology , Disease Models, Animal , Electromyography , Enzyme-Linked Immunosorbent Assay , Injections, Intraventricular , Irritable Bowel Syndrome/chemically induced , Irritable Bowel Syndrome/pathology , Irritable Bowel Syndrome/physiopathology , Male , Mechanotransduction, Cellular , Nucleobindins , Pain Perception/drug effects , Pain Threshold/drug effects , Pressure , Rats , Rats, Sprague-Dawley , Reaction Time , Reflex , Time Factors
20.
Environ Sci Technol ; 46(18): 10341-8, 2012 Sep 18.
Article in English | MEDLINE | ID: mdl-22888826

ABSTRACT

Methane is a desirable alternative to conventional fossil fuels, and also a main component of biogas from anaerobic fermentation of organic wastes. However, its relatively lower purity and poor storage by existing adsorbent materials negatively affect its wide application. Thus, efficient, cost-effective, and safe adsorbent materials for methane purification and storage are highly desired. In this study, multilayer graphene nanostructures (MGNs) with optimized structure are investigated as a potential adsorbent for this purpose. The effects of layer distance and Li doping on MGN performance in terms of methane storage and acid gas (H(2)S and CO(2)) separation from biogas are examined by molecular simulations. The mechanisms for the interactions between gas molecules and substrates are elucidated by analyzing the binding energy, geometric structures, and charge distribution from the first-principles calculations. The results show that nonhydrocarbons in biogas can be effectively separated using Li-doped MGNs with the optimal layer distance of 0.68 nm, and then the pure methane gas can be stored in MGNs with capacity satisfying the DOE target. This work offers a molecular-level insight into the interactions between gas molecules and MGNs and might provide useful information for development of new materials for methane purification and storage.


Subject(s)
Biofuels/analysis , Graphite/chemistry , Lithium/chemistry , Methane/isolation & purification , Nanostructures/chemistry , Adsorption , Molecular Dynamics Simulation
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