Plasma-induced oxygen defects in titanium dioxide to address the long-term stability of pseudocapacitive MnO2 anode for lithium ion batteries.

In this work, we developed Manganese and Titanium based oxide composites with oxygen defects (MnOx@aTiOy) via plasma processing as anodes of lithium ion batteries. By appropriately adjusting the defect concentration, the ion transport kinetics and electrical conductivity of the electrodes are significantly improved, showing stable capacity retention. Furthermore, the incremental capacity is further activated and long-term stable cycling performance is achieved, with a specific capacity of 829.5 mAh/g at 1 A/g after 2000 cycles. To scrutinize the lithium migration paths and energy barriers in MnO2 and Mn2O3, the density functional theory (DFT) calculations is performed to explore the lithium migration paths and energy barriers. Although the transformation of MnO2 into Mn2O3 through oxygen defects was initially surmised to inhibit Li ions along their standard routes, our results indicate quite the contrary. In fact, the composite's lithium diffusion rate saw a substantial increase. This can be accredited to the pronounced enhancement of conductivity and ion transport efficiency in the amorphous and porous TiOy.

Role of Fe/Co Ratio in Dual Phase Ce0.8Gd0.2O2-δ-Fe3-xCoxO4 Composites for Oxygen Separation.

Dual-phase membranes are increasingly attracting attention as a solution for developing stable oxygen permeation membranes. Ce0.8Gd0.2O2-δ-Fe3-xCoxO4 (CGO-F(3-x)CxO) composites are one group of promising candidates. This study aims to understand the effect of the Fe/Co-ratio, i.e., x = 0, 1, 2, and 3 in Fe3-xCoxO4, on microstructure evolution and performance of the composite. The samples were prepared using the solid-state reactive sintering method (SSRS) to induce phase interactions, which determines the final composite microstructure. The Fe/Co ratio in the spinel structure was found to be a crucial factor in determining phase evolution, microstructure, and permeation of the material. Microstructure analysis showed that all iron-free composites had a dual-phase structure after sintering. In contrast, iron-containing composites formed additional phases with a spinel or garnet structure which likely contributed to electronic conductivity. The presence of both cations resulted in better performance than that of pure iron or cobalt oxides. This demonstrated that both types of cations were necessary to form a composite structure, which then allowed sufficient percolation of robust electronic and ionic conducting pathways. The maximum oxygen flux is jO2 = 0.16 and 0.11 mL/cm2·s at 1000 °C and 850 °C, respectively, of the 85CGO-FC2O composite, which is comparable oxygen permeation flux reported previously.

Direct Visualization of Distorted Twin Boundaries in Ce-Doped GdFeO3.

Utilizing advanced transmission electron microscopy (TEM), the structure at the (110)-type twin boundary (TB) of Ce-doped GdFeO3 (C-GFO) has been investigated with picometer precision. Such a TB is promising to generate local ferroelectricity within a paraelectric system, while precise knowledge about its structure is still largely missing. In this work, a direct measurement of the cation off-centering with respect to the neighboring oxygen is enabled by integrated differential phase contrast (iDPC) imaging, and up to 30 pm Gd off-centering is highly localized at the TB. Further electron energy loss spectroscopy (EELS) analysis demonstrates a slight accumulation of oxygen vacancies at the TB, a self-balanced behavior of Ce at the Gd sites, and a mixed occupation of Fe2+ and Fe3+ at the Fe sites. Our results provide an informative picture with atomic details at the TB of C-GFO, which is indispensable to further push the potential of grain boundary engineering.

Ti3C2 MXene Membranes for Gas Separation: Influence of Heat Treatment Conditions on D-Spacing and Surface Functionalization.

Two-dimensional (2D) MXene materials have recently been the focus of membrane research due to their unique properties, such as their single-atomic-layer thickness, flexibility, molecular filtration abilities and microstructural similarities with graphene, which is currently the most efficient precursor material for gas separation applications. In addition, the potential to process nanoscale channels has motivated investigations of parameters which can improve membrane permeability and selectivity. Interlayer spacing and defects, which are still challenging to control, are among the most crucial parameters for membrane performance. Herein, the effect of heat treatment on the d-spacing of MXene nanosheets and the surface functionalization of nanolayers was shown regarding its impact on the gas diffusion mechanism. The distance of the layers was reduced by a factor of over 10 from 0.345 nm to 0.024 nm, the defects were reduced, and the surface functionalization was maintained upon treatment of the Ti3C2 membrane at 500 °C under an Ar/H2 atmosphere as compared to 80 °C under vacuum. This led to a change from Knudsen diffusion to molecular sieving, as demonstrated by single-gas permeation tests at room temperature. Overall, this work shows a simple and promising way to improve H2/CO2 selectivity via temperature treatment under a controlled atmosphere.

Sevoflurane preconditioning alleviates myocardial ischemia reperfusion injury through mitochondrial NAD+-SIRT3 pathway in rats. / 七氟醚预处理通过线粒体NAD+-SIRT3é€šè·¯å‡è½»å¤§é¼ å¿ƒè‚Œç¼ºè¡€å†çŒæ³¨æŸä¼¤.

OBJECTIVES: Myocardial ischemia reperfusion injury (IRI) occurs occasionally in the process of ischemic heart disease. Sevoflurane preconditioning has an effect on attenuating IRI. Preserving the structural and functional integrity of mitochondria is the key to reduce myocardial IRI. Silent information regulator 3 (SIRT3), a class of nicotinamide adenine dinucleotide (NAD+) dependent deacetylases, is an important signal-regulating molecule in mitochondria. This study aims to explore the role of mitochondrial NAD+-SIRT3 pathway in attenuating myocardial IRI in rats by sevoflurane preconditioning. METHODS: A total of 60 male Sprague Dawley (SD) rats were randomly divided into 5 groups (n=12): A sham group (Sham group), an ischemia reperfusion group (IR group), a sevoflurane preconditioning group (Sev group, inhaled 2.5% sevoflurane for 30 min), a sevoflurane preconditioning+SIRT3 inhibitor 3-TYP group (Sev+3-TYP group, inhaled 2.5% sevoflurane for 30 min and received 5 mg/kg 3-TYP), and a 3-TYP group (5 mg/kg 3-TYP). Except for the Sham group, the IR model in the other 4 groups was established by ligating the left anterior descending coronary artery. The size of myocardial infarction was determined by double staining. Serum cardiac troponin I (cTnI) level was measured. The contents of NAD+ and ATP, the activities of mitochondrial complexes I, II, and IV, the content of MDA, the activity of SOD, and the changes of mitochondrial permeability were measured. The protein expression levels of SIRT3, SOD2, catalase (CAT), and voltage dependent anion channel 1 (VDAC1) were detected by Western blotting. The ultrastructure of myocardium was observed under transmission electron microscope. MAP and HR were recorded immediately before ischemia (T0), 30 min after ischemia (T1), 30 min after reperfusion (T2), 60 min after reperfusion (T3), and 120 min after reperfusion (T4). RESULTS: After ischemia reperfusion, the content of NAD+ in cardiac tissues and the expression level of SIRT3 protein were decreased (both P<0.01), and an obvious myocardial injury occurred, including the increase of myocardial infarction size and serum cTnI level (both P<0.01). Correspondingly, the mitochondria also showed obvious damage on energy metabolism, antioxidant function, and structural integrity, which was manifested as: the activities of mitochondrial complexes I, II, and IV, ATP content, protein expression levels of SOD2 and CAT were decreased, while MDA content, VDAC1 protein expression level and mitochondrial permeability were increased (all P<0.01). Compared with the IR group, the content of NAD+ in cardiac tissues and the expression level of SIRT3 protein were increased in the Sev group (both P<0.01); the size of myocardial infarction and the level of serum cTnI were decreased in the Sev group (both P<0.01); the activities of mitochondrial complexes I, II, and IV, ATP content, protein expression levels of SOD2 and CAT were increased, while MDA content, VDAC1 protein expression level, and mitochondrial permeability were decreased in the Sev group (all P<0.01). Compared with the Sev group, the content of NAD+ in cardiac tissues and the expression level of SIRT3 protein were decreased in the Sev+3-TYP group (both P<0.01); the size of myocardial infarction and the level of serum cTnI were increased in the Sev+3-TYP group (both P<0.01); the activities of mitochondrial complexes I, II, and IV, ATP content, protein expression levels of SOD2 and CAT were decreased, while MDA content, VDAC1 protein expression level, and mitochondrial permeability were increased in the Sev+3-TYP group (all P<0.01). CONCLUSIONS: Sevoflurane preconditioning attenuates myocardial IRI through activating the mitochondrial NAD+-SIRT3 pathway to preserve the mitochondrial function.

Ultra-thin graphene cube framework@TiO2 heterojunction as high-performance anode materials for lithium ion batteries.

Here, we proposed a new strategy to build the integrated graphene cube (Gr) framework@TiO2 composite to improve the ion transport kinetics and electrical conductivity of TiO2 as a long-life and high-capacity anode for lithium ion batteries. Combined with the salt template method for ultra-thin framework, the distinct structure of Gr@TiO2 shows an excellent electrochemical performance, e.g., initial coulombic efficiency (ICE), rate performance and specific capacity, due to the increased kinetics of lithium ions. Through this method, the integrity is dramatically improved and the pulverization and agglomeration of the anode after long-term cycles are restrained. The optimized Gr@TiO2 displays a high stable reversible capacity of 179.5 mAh g-1 after 4000 cycles at 1 A g-1, excellent rate performance (125.5 mAh g-1 at 5 A g-1). Kinetic studies through Electrochemical Impedance Spectra, Galvanostatic Intermittent Titration Technique and Linear Sweep Voltammetry confirm that the electrical conductivity and ion transport kinetics are dramatically improved through the ultra-thin graphene cube framework as a heterojunction structure of Gr@TiO2.

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy.

In this study, a dual phase composite (CSO-FC2O) consisting of 60 vol % Ce0.8Sm0.2O1.9 as oxygen-conductive phase and 40 vol % FeCo2O4 as electron-conductive phase was synthesized. TEM measurements showed a relatively pure dual-phase material with only minor amounts of a tertiary (Sm,Ce)(Fe,Co)O3 perovskite phase and isolated residues of a rock salt phase at the grain boundaries. The obtained material was used as a model to demonstrate that a combination of polarization relaxation measurements and Kelvin probe force microscopy (KPFM)-based mapping of the Volta potential before and after the end of polarization can be used to determine the chemical diffusion coefficient of the ceria component of the composite. The KPFM measurements were performed at room temperature and show diffusion coefficients in the range of 3 × 10-13 cm2·s-1, which is comparable to values measured for single-phase Gd-doped ceria thin films using the same method.

DNA introduces an independent temperature responsiveness to thermosensitive microgels and enables switchable plasmon coupling as well as controlled uptake and release.

A novel DNA-microgel hybrid system with dual thermal responsiveness is introduced uitilizing covalent coupling of single stranded DNA (ssDNA) to thermoresponsive microgels (µGs). The spatial distribution of the coupling sites for the ssDNA was characterized with 3D superresolution fluorescence microscopy. The DNA-functionalized µGs remain thermoresponsive and can take up dye-labeled complementary ssDNA, which can be released again by overcoming the dehybridization temperature of the DNA independently of the volume phase transition (VPT) of the µGs. The same holds for nano-objects represented by plasmonic gold nanoparticles (AuNPs), the penetration depth of which was visualized via TEM tomography and 3D reconstruction and which show enhanced plasmonic coupling in the collapsed state of the µG and thus gets switchable. In contrast, if ssDNA was taken up just by non-specific interactions, i.e. into non-functionalized µGs, its release is temperature-independent and can only be induced by increasing the salt concentration. Thus, the incorporated ssDNA represents highly selectice binding sites determined by their base number and sequence, which makes the VPT, beeing determined by the µG composition, and the reversible uptake and release enabled through programmable DNA hybridization are independent features. The combination with the typically high biocompatibility and the retained swellability and permeability hold promise for new fundamental insights as well as for potential applications in biological environments.

Direction observation of the grain boundary segregation in molybdenum substituted lanthanum tungstate membranes.

Molybdenum substituted lanthanum tungstate membranes (LWO-Mo) offer a good alternative for the separation of hydrogen from gas mixtures. During several essential steps of the membrane processing, an intensive employment of ZrO2 milling balls is usually inevitable. However, how these milling balls affect the final LWO-Mo membranes, is still largely unknown. Employing comprehensive transmission electron microscopy (TEM) techniques, the residual Zr was found to segregate to the grain boundaries (GBs) of the LWO-Mo, either as thin layers or as individual nanograins. At atomic scale, structural and chemical analyses on these GB features were carried out quantitatively. The segregated Zr took more than half of the W sites of the LWO-Mo, resulting in a strained LWO structure and locally concentrated oxygen vacancies. To minimize any Zr contamination, either a competent alternative for ZrO2 or a careful introduction of certain secondary phases (SPs) was proposed. Our results unravel the processing-induced GB behaviors in LWO-Mo, which pave the way towards further optimized processing for various types of functional membranes.

Molecular identification of Cerithiidae (Mollusca: Gastropod) in Hainan island, China.

A number of same species of Cerithiidae are morphologically unlike, whereas most of species in the same genus are morphologically similar and just exhibit subtle differences. It is difficult to identify them by morphological methods alone. DNA barcoding is a modern molecular technique that can be used to identify species accurately, and is particularly helpful when distinguishing morphologically similar species. In order to identify species of Cerithiidae using DNA barcoding technology based on mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal RNA (16S rRNA) genes, this study calculated intraspecific and interspecific genetic distance and constructed the phylogenetic trees. A total of 80 COI and 16S rRNA barcode sequences were obtained from 10 species and 3 genera. Some unknown specimens were further identified and a cryptic species may exist in Cerithium traillii, showing that DNA barcoding technology has the potential to discover new species and cryptic species. The phylogenetic trees revealed that all of the cerithiids could converge upon a monophyly with high support values and two genera (Cerithium and Clypeomorus) maybe support the reclassification. It is necessary for traditional morphological methods to combine with the DNA barcoding for classification and identification of Cerithiidae.

Effect of obesity on the prognosis and recurrence of prostate cancer after radical prostatectomy: a meta-analysis.

BACKGROUND: Obesity has been found to be closely related to the increased risk of fatal prostate cancer (PCa), however there remains no evidence that further clarifies the relationship between obesity and the postoperative recurrence and poor prognosis of PCa. In this study, a systematic review and meta-analysis were performed to systematically evaluate the effect of obesity on the prognosis and recurrence of PCa after radical prostatectomy (RP). METHODS: A literature search of the PubMed, Web of Science, and Embase databases was performed covering articles published between January 2013 and January 2020. Articles regarding the correlation between body mass index (BMI) and the prognosis and recurrence of PCa following RP were included in the meta-analysis. Two investigators independently screened the literature and extracted relevant data including publication information, key results, number of cancer cases, and multivariable-adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Meta-analysis was performed using RevMan 5.3 and Stata 16.0 software, and forest plots, funnel plots, and sensitivity analysis were also conducted. RESULTS: A total of 14 articles were included, all of which were analyzed for clinicopathological characteristics. Eight articles reported the biochemical recurrence (BCR) with prostate-specific antigen (PSA) as the predictor, and six articles reported the positive surgical margins (PSM). The meta-analysis showed that obese PCa patients had more postoperative recurrence and poor prognosis compared with the normal weight PCa patients, and the difference was statistically significant (OR =1.25, 95% CI: 1.10, 1.43). BCR exhibited no significant difference between obese and non-obese PCa patients after surgery (OR =1.2, 95% CI: 0.96, 1.46), and there were also no notable differences in PSM between the groups (OR =1.16, 95% CI: 0.99, 1.36). Subgroup analysis showed that obese PCa patients in the Americas (95% CI: 1.11, 1.37) and Europe (95% CI: 1.11, 1.78) were more likely to have surgical recurrence and poor prognosis (OR =1.40). Obese patients in the Americas were also more likely to have BCR after surgery (95% CI: 1.07, 1.36). CONCLUSIONS: Obesity easily leads to poor prognosis and recurrence of PCa after RP.

Tamsulosin Monotherapy Is Effective in Reducing Ureteral Stent-related Symptoms: A Meta-analysis of Randomized Controlled Studies.

This study aimed to evaluate the effectiveness of tamsulosin monotherapy for the treatment of ureteral stent-related symptoms (SRSs) and compare it with that of solifenacin monotherapy and combined therapy of tamsulosin and silifenacin. Randomized controlled trials (RCTs), which evaluated the effectiveness of tamsulosin for the treatment of SRSs, were searched from the databases PubMed, EMBASE and the Cochrane Library published up to November 2018. Eight RCTs involving 1087 participants were finally included in this meta-analysis. The results showed that tamsulosin monotherapy could significantly decrease the urinary symptoms [mean difference (MD) -7.56, 95% confidence interval (CI) (-11.47, -3.65), P=0.0001] and body pain [MD -5.25, 95% CI (-8.03, -2.46), P=0.0002], and improve the sexual performance [MD -1.06, 95% CI (-1.89, -0.24), P=0.01] compared with the control group. Moreover, there was no significant difference between tamsulosin monotherapy and solifenacin monotherapy in all outcomes except for significantly better sexual performance in solifenacin group [MD 0.29, 95% CI (0.06, 0.51), P=0.01]. In addition, the effectiveness of combined therapy of tamsulosin and solifenacin was not superior to that of tamsulosin monotherapy. Our study demonstrated that tamsulosin monotherapy was effective for the treatment of patients with SRSs; evident superiority could not be found for therapy of tamsulosin and solifenacin combined.

Dexmedetomidine may upregulate the expression of caveolin­1 in lung tissues of rats with sepsis and improve the short­term outcome.

Dexmedetomidine (DXM) is a selective α2-adrenoceptor (α2­AR) and imidazoline receptor (IR) agonist that has been reported to regulate inflammatory responses mediated by diverse signaling pathways through α2­AR. The majority of the reported receptors or downstream molecules have been demonstrated to locate with caveolin­1, a protein suggested to participate in regulating Toll­like receptor 4 (TLR4)­mediated inflammatory responses and the pathogen endocytosis capability of macrophages. The present study hypothesized that DXM may influence these pathways by regulating the expression of caveolin­1 and mediating the subsequent effects. Using a cecal­ligation and puncture­induced rat sepsis model, it was initially observed that pre­emptive DXM is able to upregulate and stabilize the amount of caveolin­1 expression, which may be partly antagonized by both α2­AR and the IR antagonist atepamezole (APZ). The pathophysiological parameters indicated that DXM is able to inhibit secondary lung injury, in addition to the rise of body temperature and arterial lactate accumulation, however it marginally increased arterial glucose and the murine sepsis score, which can be largely antagonized by APZ. The overall effect was beneficial and improved the 24­h cumulative survival rate of rats with sepsis. In conclusion, preemptive clinical sedative doses of DXM may upregulate the expression of caveolin­1 downregulated by sepsis, which may contribute to the inhibition of inflammatory pathways such as TLR4­mediated pathways. Furthermore, DXM may favor the improvement of short­term outcomes by the regulation of other metabolic pathways.

Switching behaviour of individual Ag-TCNQ nanowires: an in situ transmission electron microscopy study.

The organic semiconductor silver-tetracyanoquinodimethane (Ag-TCNQ) exhibits electrical switching and memory characteristics. Employing a scanning tunnelling microscopy setup inside a transmission electron microscope, the switching behaviour of individual Ag-TCNQ nanowires (NWs) is investigated in detail. For a large number of NWs, the switching between a high (OFF) and a low (ON) resistance state was successfully stimulated by negative bias sweeps. Fitting the experimental I-V curves with a Schottky emission function makes the switching features prominent and thus enables a direct evaluation of the switching process. A memory cycle including writing, reading and erasing features is demonstrated at an individual NW. Moreover, electronic failure mechanisms due to Joule heating are discussed. These findings have a significant impact on our understanding of the switching behaviour of Ag-TCNQ.

A microspectroscopic insight into the resistivity switching of individual Ag-TCNQ nanocrystals.

We investigate the resistivity switching in individual Ag-TCNQ wires with on/off-ratios of up to 10(3). Raman and soft X-ray absorption microspectroscopy studies disclose reverse charge transfer. Quantifying of the fraction of neutral TCNQ within the switched material yields values up to 22.3%. These findings expedite the understanding of the switching process in Ag-TCNQ nanowires.

Differential hippocampal protein expression between normal aged rats and aged rats with postoperative cognitive dysfunction: A proteomic analysis.

The aim of the present study was to investigate the differences in the expression of hippocampal proteins between normal control aged rats and aged rats with postoperative cognitive dysfunction (POCD). A total of 24 aged rats were randomly divided into a surgery group (n=12) and a control group (n=12). The rats in the surgery group were treated with 2 h isoflurane anesthesia and splenectomy, while the rats in the control group received 40% oxygen for 2 h without surgery. The cognitive functions of the two groups were examined using a Y-maze test. The protein expression profiles of the hippocampus of six aged rats (three rats with POCD and three from the normal control group) were assessed using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time of flight mass spectrometry. A total of three differential proteins were further confirmed between the POCD rats and normal rats using reverse transcription quantitative polymerase chain reaction (RT-qPCR). The expression levels of 21 proteins in the rats with POCD were significantly different compared with the normal control rats. These proteins were functionally clustered to synaptic plasticity (three proteins), oxidative stress (four proteins), energy production (six proteins), neuroinflammation (three proteins) and glutamate metabolism (two proteins). In addition, three proteins (fatty acid binding protein 7, brain, glutamate dehydrogenase 1 and glutamine synthetase), associated with astrocytic function, were significantly different in the rats with POCD compared with those in the normal control (P<0.05). Similar changes in the mRNA expression levels of the three proteins in the hippocampi of POCD rats were also detected using RT-qPCR. Neuroinflammation, glutamate toxicity and oxidative stress were possibly involved in the pathological mechanism underlying POCD in aged rats. In addition, astrocytes may also be important in POCD in aged rats.

Self-healing of bended WS2 nanotubes and its effect on the nanotube's properties.

Individual WS(2) nanotubes (NTs) were bended and released in-situ inside a transmission electron microscope. Kinks appeared in the NTs suddenly during the bending process. Shell distortion, shell breaking and rotation of broken shells were observed in these kinks. Spontaneous self-healing and focused electron beam-assisted healing of the structure were observed after the load was removed. More importantly, the strength and electrical conductivity of the NTs were also restored to their original level when the structure recovered.

[Effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats].

OBJECTIVE: To investigate the effects of hydrogen sulfide preconditioning on myocardial ischemia reperfusion injury in rats. METHODS: Sprague-Dawley male rats were divided into 4 groups with 10 in each group: in S group rats received sham operation; in IR group rats were given with NS (1.0 ml/kg iv) 24 h before ischemia; in H group rats were treated with NaHS (0.05 mg/kg iv) 24 h before ischemia; and in D group, NaHS-treated rats received 5-hydroxydecanoate (5-HD) 15 min before ischemia. Rats in IR group,H group and D group were subjected to ischemia by occlusion of coronary artery for 30 min followed by 2 h of reperfusion. At the end of the reperfusion,myocardial infarct size was measured. SAM-s was measured by Western blotting. Plasma SOD activity and MDA were determined at the end of reperfusion. RESULTS: The infarct size was significantly lesser in H group (25.40 % ± 3.54%) than that in IR group (38.27% ±5.64%,P<0.05). The SAM-s protein expression in myocardium was significantly lower in H group than that in IR group. The plasma MDA content was significantly lower and SOD activity was higher in H group than those in IR group,but there was no difference between IR group and D group. CONCLUSION: The hydrogen sulfide preconditioning attenuates myocardial IR injury possibly through down-regulating SAM-s expression,reducing the production of oxygen free radicals and enhancing anti-oxidize effect in rats.

[Proteomics analysis of myocardium after delayed preconditioning with hydrogen sulfide in rat].

OBJECTIVE: To investigate the changes in protein of myocardium after hydrogen sulfide delayed preconditioning by using proteomics technology. METHODS: Sixteen Sprague-Dawley rats were randomly assigned to control (group S) or hydrogen sulfide group (group H), n = 8 for each group. Myocardial ischemia/reperfusion injury model (ischemia 30 minutes followed by reperfusion 120 minutes) was reproduced at 24 hours after preconditioning either with normal saline or hydrogen sulfide for proteomics analysis in group S or group H, and the myocardial tissue was harvested. The total proteins were extracted and separated by two dimensional gel electrophoresis (2-DE), and the differential protein expression spots were analyzed with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). RESULTS: Analysis of 2-DE showed that 929 ± 14 protein spots were found in group S and 906 ± 10 protein spots in group H, and the expression of 15 protein spots was different between two groups. These protein spots were chosen to undergo MALDI-TOF-MS analysis, and 11 proteins were preliminarily identified, including DNA ligase, cystathionine gamma-lyase, transcription initiation factor, NADH dehydrogenase, guanine nucleotide-releasing factor, fructose-bisphosphate aldolase A, glycogen synthase kinase-3, electron transfer flavoprotein subunit beta, glutathione S-transferase, soluble calcium-activated nucleotidase and S-adenosylmethionine synthetase. CONCLUSIONS: Hydrogen sulfide delayed preconditioning of myocardium resulted in the changes in protein expression profiles in the myocardium. The differential proteins might function as anti-oxidants, to improve the energy metabolism of myocardium, confer cytoprotection and protection of respiratory chain, thus conferring cardioprotection.

[Effect of Gingkgo biloba leaf extract induced delayed preconditioning on cytochrome c oxidase expression during myocardial ischemia-reperfusion in rats].

OBJECTIVE: To determine the effect of Gingkgo biloba leaf extract (EGb761) induced delayed preconditioning on cytochrome c oxidase (CcO) expression during myocardial ischemia-reperfusion in rats. METHODS: Four groups (10 in each) of Sprague-Dawley male rats were studied. In the sham group, the rats received no treatment. Rats in the ischemia-reperfusion (IR) group were treated with NS (1.0 mL/kg intravenously) 24 h before ischemia. Rats in the M group were treated with EGb761 (100 mg/kg intravenously) 24 h before the ischemia. In the D group , EGb761-treated rats that received the 5-hydroxydecanoate (5-HD), an inhibitor of mitochondrial KATP channels 15 min before the ischemia. The IR, M, and D groups were subjected to ischemia by 30 min of coronary artery occlusion before 2 h of reperfusion. At the end of the reperfusion, myocardial infarct size was measured. CcO was measured by Western blot. The myocardial ultrastructure was observed under the electron microscope. RESULTS: The infarct size was significantly smaller in the M group [(23.78 ± 4.82)%] than in the I/R group [(37.87 ± 5.92)%] (P<0.05). The CcO protein expression in the myocardium was significantly higher in the M group than in the I/R group(P<0.05). Microscopic examination showed less myocardial damage in the M group than that in the I/R group. The infarct size, CcO protein expression, and myocardial damage had no significant difference between the D group and the I/R group (P>0.05). CONCLUSION: EGb761 induced delayed preconditioning attenuates myocardial ischemia-reperfusion injury possibly through up-regulating CcO expression in rats.