AIM: To investigate whether high-fat-feeding is associ- ated with increased intestinal permeability via altera- tions in bile acid metabolism.METHODS: Male C57BI/6J mice were fed on a high-fat (n = 26) or low-fat ...AIM: To investigate whether high-fat-feeding is associ- ated with increased intestinal permeability via altera- tions in bile acid metabolism.METHODS: Male C57BI/6J mice were fed on a high-fat (n = 26) or low-fat diet (n = 24) for 15 wk. Intestinal permeability was measured from duodenum, jejunum, ileum and colon in an Ussing chamber system using 4 kDa FITC-labeled dextran as an indicator. Fecal bile ac- ids were analyzed with gas chromatography. Segments of jejunum and colon were analyzed for the expression of farnesoid X receptor (FXR) and tumor necrosis factor展开更多
AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A contr...AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.展开更多
Voltage-dependent anion channel (VDAC)I is the main channel of the mitochondrial outer membrane (MOM) and it has been proposed to be part of the permeability transition pore (PTP), a putative multiprotein comple...Voltage-dependent anion channel (VDAC)I is the main channel of the mitochondrial outer membrane (MOM) and it has been proposed to be part of the permeability transition pore (PTP), a putative multiprotein complex candidate agent of the mitochondrial permeability transition (MPT). Working at the single live cell level, we found that overexpression of VDAC1 triggers MPT at the mitochondrial inner membrane (MIM). Conversely, silencing VDAC1 ex- pression results in the inhibition of MPT caused by selenite-induced oxidative stress. This MOM-MIM crosstalk was modulated by Cyclosporin A and mitochondrial Cyclophilin D, but not by Bcl-2 and BcI-XL, indicative of PTP operation. VDAC1-dependent MPT engages a positive feedback loop involving reactive oxygen species and p38-MAPK, and secondarily triggers a canonical apoptotic response including Bax activation, cytochrome e release and caspase 3 activation. Our data thus support a model of the PTP complex involving VDAC1 at the MOM, and indicate that VDACl-dependent MPT is an upstream mechanism playing a causal role in oxidative stress-induced apoptosis.展开更多
As is the case in all parts of gastroenterology and hepatology,there have been many advances in our knowledge and understanding of small intestinal diseases.Over 1000 publications were reviewed for 2008 and 2009,and t...As is the case in all parts of gastroenterology and hepatology,there have been many advances in our knowledge and understanding of small intestinal diseases.Over 1000 publications were reviewed for 2008 and 2009,and the important advances in basic science as well as clinical applications were considered.In Part Ⅰ of this Editorial Review,seven topics are considered:intestinal development;proliferation and repair;intestinal permeability;microbiotica,infectious diarrhea and probiotics;diarrhea;salt and water absorption;necrotizing enterocolitis;and immunology/allergy.These topics were chosen because of their importance to the practicing physician.展开更多
Created a new damage model for explosive for LS-DYNA3D,taking advantageof the Taylor method aimed at the high gassy and low permeability coal seam,and numericallysimulated and analyzed the deep-hole presplitting explo...Created a new damage model for explosive for LS-DYNA3D,taking advantageof the Taylor method aimed at the high gassy and low permeability coal seam,and numericallysimulated and analyzed the deep-hole presplitting explosion.The entire processof explosion was represented,including cracks caused by dynamic pressure,transmissionand vibration superposition of stress waves,as well as cracks growth driven by gas generatedby explosion.The influence of the cracks generated in the process of explosion andthe performance of improving permeability caused by the difference of interval between.explosive holes were analyzed.A reasonable interval between explosive holes of deepholepresplitting explosions in high gassy and low permeability coal seams was proposed,and the resolution of gas drainage in high gassy and low permeability coal seam was putforward.展开更多
The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (...The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (Machilus yunnanensis) in Yunnan Province and the introduced tree species (Cinnamomum camphora). The leaf water potential, chlorophyll content, proline content and plasma membrane permeability for two species seedlings were measured in different soil drought conditions. The results showed that, on the 9th day of drought stress, the leaf water potential of two species decreased obviously, whereas the free proline content and plasma membrane permeability increased sharply. On the 11th day, the leaf water potential of C. camphora seedlings was lower than that of M. yunnanensis seedlings; the plasma membrane permeability in C. camphora seedling leaves increased much more than that in M. yunnanensis seedling leaves, which showed that the injury to the former by soil drought stress was more severe than that to the latter. The free proline content in M. yunnanensis seedling leaves continued to increase on the 11th day, but that in the C. camphora seedling leaves started to drop obviously, indicating that the reduction of osmotic regulation substance in C. camphora seedling leaves after the 11th day was unable to maintain the osmotic balance between the plasma system and its surroundings and the water loss occurred inevitably. Comprehensively, M. yunnanensis seedlings enhanced the drought-resistance in the course of soil drought stress by maintaining higher leaf water potential and by increasing osmotic regulation substance to promote cell plasma concentration and maintain membrane structure integrity so as to reduce water loss. The subordination function index evaluated with fuzzy mathematic theory also showed that the drought-resistant capacity of M. yunnanensis seedlings was stronger than that of C. camphora seedlings.展开更多
AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate...AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate as an index of IP,induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α,assessed the results using an enzymatic-spectrophotometric method,transmission electron microscopy,immunohistochemistry,Western blotting and real-time quantitative polymerase chain reaction.The effect of the administration of antiTNF-α immunoglobulin G(IgG) antibody,before the administration of D-galactosamine/lipopolysaccharide,on TNF-α was also assessed.RESULTS:IP was significantly increased in the mouse model of FHF 6 h after injection(13.57 ± 1.70 mg/L,13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.001).Electron microscopic analysis revealed tight junction(TJ) disruptions,epithelial cell swelling,and atrophy of intestinal villi.Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models(occludin:0.57 ± 0.159 fold vs baseline,P = 0.000;claudin-1:0.3067 ± 0.1291 fold vs baseline,P = 0.003),as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein(occludin:0.61 ± 0.0473 fold vs baseline,P = 0.000;claudin-1:0.6633 ± 0.0328 fold vs baseline,P = 0.000).Prophylactic treatment with antiTNF-α IgG antibody prevented changes in IP(4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.791),intestinal tissue ultrastructure,and the mRNA levels of occludin and claudin-1 expression(occludin:0.8865 ± 0.0274 fold vs baseline,P = 0.505;claudin-1:0.85 ± 0.1437 fold vs baseline,P = 0.1),and in the protein levels(occludin:0.9467 ± 0.0285 fold vs baseline,P > 0.05;claudin-1:0.9533 ± 0.0186 fold vs baseline,P = 0.148).CONCLUSION:Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1,and destruction of the TJ in the colon,which were induced by TNF-α in FHF mice.展开更多
Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability increase.Slotting the seam by auxiliary drilling with a water jet...Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability increase.Slotting the seam by auxiliary drilling with a water jet that breaks the coal and slots the coal seam during the process of retreat drilling achieves pressure relief and permeability increase.Improved efficiency of gas extraction from a field test,high gas coal seam was observed.Investigating the theory of pressure relief and permeability increase required analyzing the characteristics of the double power slotting process and the effects of coal pressure relief and permeability increase.The influence of confining pressure on coal physical properties was examined by using FLAC3D software code to simulate changes of coal stress within the tool destruction area.The double power joint drilling method was modeled.Field experiments were performed and the effects are analyzed.This research shows that there is an ''islanding effect'' in front of the joint double power drill and slotting equipment.The failure strength of the coal seam is substantially reduced within the tool destruction area.Drilling depths are increased by 72% and the diameter of the borehole is increased by 30%.The amount of powdered coal extracted from the drill head increases by 17 times when using the new method.A 30 day total flow measurement from the double power drilled and slotted bores showed that gas extraction increased by 1.3 times compared to the standard drilled bores.Gas concentrations increased from 30% to 60% and were more stable so the overall extraction efficiency increased by a factor of two times.展开更多
Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue type...Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue (dBPI), 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 (BPIL1) and BPI like 3 (BPIL3) of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 (5) : 376 - 382, 2009].展开更多
As for the coal seam with high stress,high gas and low permeability,a single technology cannot prevent the complex dynamic disasters.Because of this,the study proposes a new method of pressure-relief and permeability-...As for the coal seam with high stress,high gas and low permeability,a single technology cannot prevent the complex dynamic disasters.Because of this,the study proposes a new method of pressure-relief and permeability-increase technology of the high liquid–solid coupling blast.Through coal seam injection and charging structure change,the paper fully works out the dual functions of the water and explosion.Using the theoretical calculation,numerical simulation and physical experiments,we obtained that the initial blasting stress,displacement and overpressure of the liquid–solid coupling blast are much better than that of ordinary blasting.The technology has been used in the relative coal mine,and the application results show that the technique has effectively prevented the coal and gas outburst,which has a wide range of application.展开更多
AIM:To investigate the effect of administration of agmatine(AGM) on gastric protection against ischemia reperfusion(I/R) injury.METHODS:Three groups of rats(6/group);sham,gastric I/R injury,and gastric I/R + AGM(100 m...AIM:To investigate the effect of administration of agmatine(AGM) on gastric protection against ischemia reperfusion(I/R) injury.METHODS:Three groups of rats(6/group);sham,gastric I/R injury,and gastric I/R + AGM(100 mg/kg,i.p.given 15 min prior to gastric ischemia) were recruited.Gastric injury was conducted by ligating celiac artery for 30 min and reperfusion for another 30 min.Gastric tissues were histologically studied and immunostained with angiopoietin 1(Ang-1) and Ang-2.Vascular endothelial growth factor(VEGF) and monocyte chemoattractant protein-1(MCP-1) were measured in gastric tissue homogenate.To assess whether AKt/phosphatidyl inositol-3-kinase(PI3K) mediated the effect of AGM,an additional group was pretreated with Wortmannin(WM)(inhibitor of Akt/PI3K,15 μg/kg,i.p.),prior to ischemic injury and AGM treatment,and examined histologically and immunostained.Another set of experiments was run to study vascular permeability of the stomach using Evan's blue dye.RESULTS:AGM markedly reduced Evan's blue dye extravasation(3.58 ± 0.975 μg/stomach vs 1.175 ± 0.374 μg/stomach,P < 0.05),VEGF(36.87 ± 2.71 pg/100 mg protein vs 48.4 ± 6.53 pg/100 mg protein,P < 0.05) and MCP-1 tissue level(29.5 ± 7 pg/100 mg protein vs 41.17 ± 10.4 pg/100 mg protein,P < 0.01).It preserved gastric histology and reduced congestion.Ang-1 and Ang-2 immunostaining were reduced in stomach sections of AGM-treated animals.The administration of WM abolished the protective effects of AGM and extensive hemorrhage and ulcerations were seen.CONCLUSION:AGM protects the stomach against I/R injury by reducing vascular permeability and inflammation.This protection is possibly mediated by Akt/PI3K.展开更多
The activity of whole-cell biocatalysts is strongly compromised by the cell envelope, which is a permeability harrier against the diffusion of substrates and products. Although common chemical or physical permeahiliza...The activity of whole-cell biocatalysts is strongly compromised by the cell envelope, which is a permeability harrier against the diffusion of substrates and products. Although common chemical or physical permeahilization methods used in cultured cells enhance cell permeability, these methods inevitably add several extra processing steps after cell cultivation, as well as impede large scale processing. To increase membrane permeability and cell- bound glutamate decarboxylase (GAD) activity of recombinant Escherichia coil (BL21 (DE3)-pET28a-gadB) cells without the need for an additional permeabilization step, we investigated the permeabilizing effects of adding cell wall synthesis inhibitors or suffactants to the culture media. Ampidllin was the most effective at improving cell-bound GAD activity of the BL21 (DE3)-pET28a-gadB, although it decreased the cell biomass yield. The best permeabilization effect was observed using an ampicillin concentration of 5 pg. ml-1. Using this concentration, the cell hiomass did decrease by 40.58%, but the cell-bound GAD activity of BL21 (DE3)-pET28a-gadB and total cell-bound GAD activity per milliliter of culture was enhanced by 6.24- and 3.64-fold, respectively. Treatment ofBL21 (DE3)-pET28a-gadB cells with 5 tag.ml 1 ampicillin resulted in structural changes to the cell envelope, but did not substantially affect GAD expression. By entrapping the ampicillin-treated cells in an open pore gelation matrix, which is a polymer derived from polyvinyl alcohol (PVA), alginate, and boric acid, the transfor- mation rate of γ-aminobutyric acid (GABA) at the 10th cycle produced by immobilized and permeabilized cells remained 46% of the first cycle. GAD activity of the immobilized, permeabilized cells remained over 90% after 30 days of storage at 4 ℃.展开更多
Cromakalim,an adenosine triphosphate-sensitive potassium channel opener,exhibits protective effects on cerebral ischemia/reperfusion injury.However,there is controversy as to whether this effect is associated with aqu...Cromakalim,an adenosine triphosphate-sensitive potassium channel opener,exhibits protective effects on cerebral ischemia/reperfusion injury.However,there is controversy as to whether this effect is associated with aquaporin-4 and blood-brain barrier permeability.Immunohistochemistry results show that preventive administration of cromakalim decreased aquaporin-4 and IgG protein expression in rats with ischemia/reperfusion injury;it also reduced blood-brain barrier permeability,and alleviated brain edema,ultimately providing neuroprotection.展开更多
In normal condition, intestine mucosa possesses barrier function. When the barrier function of intestine mucosa was damaged, intestinal bacteria, endotoxin, or other substances would enter blood. It is generally accep...In normal condition, intestine mucosa possesses barrier function. When the barrier function of intestine mucosa was damaged, intestinal bacteria, endotoxin, or other substances would enter blood. It is generally accepted that biliary bacteria origins from the intestine either via duodenal papilla or intestinal mucosa. In this study, we aimed to investigate the intestinal permeability changes of cholelithiasis patients to elucidate the possible pathogenesis of cholelithiasis.展开更多
Background Hypoxemia sometimes occurs in the emergency room in the patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI), even in those with administration of conventional ...Background Hypoxemia sometimes occurs in the emergency room in the patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI), even in those with administration of conventional high-flow oxygen inhalation. The objective of the present study was to evaluate the effectiveness of non-invasive ventilation (NIV) in improving blood oxygen content and hemorheology in patients with AMI and hypoxemia. Methods This prospective study enrolled 50 consecutive eligible patients with AMI (aged 72.3 ± 9.5 years), who had undergone PCI and been administered high-flow oxygen but still had hypoxemia. Blood was taken before NIV and at 0.5, 1, and 2 h after NIV. Blood gases, hemorheological variables including erythrocyte deformability, erythrocyte aggregation, erythrocyte osmotic fragility, membrane fluidity, and oxidative stress level were measured. Results Blood PaO2 increased to normal by 1 h after NIV. Assessed hemorheological variables had all improved and plasma malondialdehyde concentration decreased significantly after 2 h of NIV. Conclusions Our data suggest that NIV can help to improve blood oxygen content, hemorheological status, and minimize plasma lipid peroxidation injury in hypoxemic patients with AMI who have undergone PCI.展开更多
Background The induced pluripotent stem cell (iPSC) has shown great potential in cellular therapy of myocardial infarction (MI), while its application is hampered by the low efficiency of cardiomyocyte differentia...Background The induced pluripotent stem cell (iPSC) has shown great potential in cellular therapy of myocardial infarction (MI), while its application is hampered by the low efficiency of cardiomyocyte differentiation. The present study was designed to investigate the effects of cardiotrophin-1 (CT-1) on cardiomyocyte differentiation from mouse induced pluripotent stem cells (miPSCs) and the underlying mechanisms involved. Methods The optimal treatment condition for cardiomyocyte differentiation from miPSCs was established with ideal concentration (10 ng/mL) and duration (from day 3 to day 14) of CT-1 administration. Up-regulated expression of cardiac specific genes that accounted for embryonic cardiogenesis was observed by quantitative RT-PCR. Elevated amount of a-myosin heavy chain (ct-MHC) and cardiac troponin I (cTn I) positive cells were detected by immunofluorescence staining and flow cytometry analysis in CT- 1 group. Results Transmission electron microscopic analysis revealed that cells treated with CT- 1 showed better organized sacromeric structure and more mitochondria, which are morphological characteristic of matured cardiomyocytes. Western blot demonstrated that CT-1 promotes cardiomyocyte differentiation from miPSCs partly via JAK2/STAT3/Pim-1 pathway as compared with control group. Conclusions These findings suggested that CT-1 could enhance the cardiomyocyte differentiation as well as the maturation of mouse induced pluripotent stem cell derived cardiomyocytes by regulating JAK2/STAT3/Pim-1 signaling pathway.展开更多
Cobalt-free perovskite-type oxides BaFel_yTayO3-6 (0 _〈 y -〈 0.2) were synthesized via a simple solid state reac- tion. The cubic perovskite structure can be obtained when y is over 0.1. BaFeo.Ta0.lO3-6 (BFT0.1)...Cobalt-free perovskite-type oxides BaFel_yTayO3-6 (0 _〈 y -〈 0.2) were synthesized via a simple solid state reac- tion. The cubic perovskite structure can be obtained when y is over 0.1. BaFeo.Ta0.lO3-6 (BFT0.1) membrane shows the highest oxygen permeation flux, which can reach 1.6 ml. min- 1. cm-2 at 950 ℃ under the gradient of air/He. The O2-TPD results reveal that BaFe0.9Ta0.lO3-a material shows an excellent reversibility and phase structure stability in air. The oxygen permeation flux is limited by the bulk diffusion when the membrane thick- ness is over 0.8 mm, and it is limited by both the bulk diffusion and the surface exchange when the membrane thickness is below 0.5 mm. Stable oxygen permeation fluxes are obtained during 180 h operation.展开更多
In this study, orange G dye was efficiently removed from aqueous solution by ultraflltration (UF) membrane separation enhanced with activated carbon adsorption. The powdered activated carbon (PAC) was deposited on...In this study, orange G dye was efficiently removed from aqueous solution by ultraflltration (UF) membrane separation enhanced with activated carbon adsorption. The powdered activated carbon (PAC) was deposited onto the UF membrane surface, forming an intact filter cake. The enhanced UF process simultaneously exploited the high water permeation flux of porous membrane and the high adsorption ability of PAC toward dye molecules. The influencing factors on the dye removal were investigated. The results indicated that with sufficient PAC incorporation, the formation of intact PAC filtration cake led to nearly complete rejection for dye solution under opti-mized dye concentration and operation pressure, without large sacnticlng the permeation tlux ot the filtration process. Typically, the dye rejection ratio increased from 43.6% for single UF without adsorption to nearly 100% for the enhanced UF process, achieving long time continuous treatment with water permeation flux of 47 L·m^-2·h^-1. The present study demonstrated that adsorption enhanced UF may be a feasible method for the dye wastewater treatment.展开更多
A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All trav...A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All travelers were divided into two classes. The first guided travelers were referred to as the equipped travelers who follow ATIS advice, while the second unguided travelers were referred to as the unequipped travelers and the equipped travelers who do not follow the ATIS advice(also referred to as non-complied travelers). Travelers were assumed to take travel time, congestion pricing, and travel time reliability into account when making travel route choice decisions. In order to arrive at on time, travelers needed to allow for a safety margin to their trip.The market penetration of ATIS was determined by a continuous increasing function of the information benefit, and the ATIS compliance rate of equipped travelers was given as the probability of the actually experienced travel costs of guided travelers less than or equal to those of unguided travelers. The analysis results could enhance our understanding of the effect of travel demand level and travel time reliability confidence level on the ATIS market penetration and compliance rate; and the effect of travel time perception variation of guided and unguided travelers on the mean travel cost savings(MTCS) of the equipped travelers, the ATIS market penetration, compliance rate, and the total network effective travel time(TNETT).展开更多
基金Supported by The Foundation for Nutrition Research and the Finnish Funding Agency of Technology and Innovation
文摘AIM: To investigate whether high-fat-feeding is associ- ated with increased intestinal permeability via altera- tions in bile acid metabolism.METHODS: Male C57BI/6J mice were fed on a high-fat (n = 26) or low-fat diet (n = 24) for 15 wk. Intestinal permeability was measured from duodenum, jejunum, ileum and colon in an Ussing chamber system using 4 kDa FITC-labeled dextran as an indicator. Fecal bile ac- ids were analyzed with gas chromatography. Segments of jejunum and colon were analyzed for the expression of farnesoid X receptor (FXR) and tumor necrosis factor
文摘AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice. METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity. RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling. CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.
文摘Voltage-dependent anion channel (VDAC)I is the main channel of the mitochondrial outer membrane (MOM) and it has been proposed to be part of the permeability transition pore (PTP), a putative multiprotein complex candidate agent of the mitochondrial permeability transition (MPT). Working at the single live cell level, we found that overexpression of VDAC1 triggers MPT at the mitochondrial inner membrane (MIM). Conversely, silencing VDAC1 ex- pression results in the inhibition of MPT caused by selenite-induced oxidative stress. This MOM-MIM crosstalk was modulated by Cyclosporin A and mitochondrial Cyclophilin D, but not by Bcl-2 and BcI-XL, indicative of PTP operation. VDAC1-dependent MPT engages a positive feedback loop involving reactive oxygen species and p38-MAPK, and secondarily triggers a canonical apoptotic response including Bax activation, cytochrome e release and caspase 3 activation. Our data thus support a model of the PTP complex involving VDAC1 at the MOM, and indicate that VDACl-dependent MPT is an upstream mechanism playing a causal role in oxidative stress-induced apoptosis.
文摘As is the case in all parts of gastroenterology and hepatology,there have been many advances in our knowledge and understanding of small intestinal diseases.Over 1000 publications were reviewed for 2008 and 2009,and the important advances in basic science as well as clinical applications were considered.In Part Ⅰ of this Editorial Review,seven topics are considered:intestinal development;proliferation and repair;intestinal permeability;microbiotica,infectious diarrhea and probiotics;diarrhea;salt and water absorption;necrotizing enterocolitis;and immunology/allergy.These topics were chosen because of their importance to the practicing physician.
基金Supported by the National Science Foundation of China(50534090,2007BAK28B01,2007BAK29B06)the Science Foundation of Anhui Province(050440403)Creative Team Plan for High School of Anhui(2006KJ005TD)
文摘Created a new damage model for explosive for LS-DYNA3D,taking advantageof the Taylor method aimed at the high gassy and low permeability coal seam,and numericallysimulated and analyzed the deep-hole presplitting explosion.The entire processof explosion was represented,including cracks caused by dynamic pressure,transmissionand vibration superposition of stress waves,as well as cracks growth driven by gas generatedby explosion.The influence of the cracks generated in the process of explosion andthe performance of improving permeability caused by the difference of interval between.explosive holes were analyzed.A reasonable interval between explosive holes of deepholepresplitting explosions in high gassy and low permeability coal seams was proposed,and the resolution of gas drainage in high gassy and low permeability coal seam was putforward.
基金This research was supported by Research Fund of Southwest Forestry College (200510)
文摘The soil drought stress experiment in different durations (no watering within 3d, 6d, 9d, 11d individually) was conducted to study the drought-resistant capacity of one-year-old seedlings for the native tree species (Machilus yunnanensis) in Yunnan Province and the introduced tree species (Cinnamomum camphora). The leaf water potential, chlorophyll content, proline content and plasma membrane permeability for two species seedlings were measured in different soil drought conditions. The results showed that, on the 9th day of drought stress, the leaf water potential of two species decreased obviously, whereas the free proline content and plasma membrane permeability increased sharply. On the 11th day, the leaf water potential of C. camphora seedlings was lower than that of M. yunnanensis seedlings; the plasma membrane permeability in C. camphora seedling leaves increased much more than that in M. yunnanensis seedling leaves, which showed that the injury to the former by soil drought stress was more severe than that to the latter. The free proline content in M. yunnanensis seedling leaves continued to increase on the 11th day, but that in the C. camphora seedling leaves started to drop obviously, indicating that the reduction of osmotic regulation substance in C. camphora seedling leaves after the 11th day was unable to maintain the osmotic balance between the plasma system and its surroundings and the water loss occurred inevitably. Comprehensively, M. yunnanensis seedlings enhanced the drought-resistance in the course of soil drought stress by maintaining higher leaf water potential and by increasing osmotic regulation substance to promote cell plasma concentration and maintain membrane structure integrity so as to reduce water loss. The subordination function index evaluated with fuzzy mathematic theory also showed that the drought-resistant capacity of M. yunnanensis seedlings was stronger than that of C. camphora seedlings.
基金Supported by National Ministry of Health of China,No.97100252
文摘AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate as an index of IP,induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α,assessed the results using an enzymatic-spectrophotometric method,transmission electron microscopy,immunohistochemistry,Western blotting and real-time quantitative polymerase chain reaction.The effect of the administration of antiTNF-α immunoglobulin G(IgG) antibody,before the administration of D-galactosamine/lipopolysaccharide,on TNF-α was also assessed.RESULTS:IP was significantly increased in the mouse model of FHF 6 h after injection(13.57 ± 1.70 mg/L,13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.001).Electron microscopic analysis revealed tight junction(TJ) disruptions,epithelial cell swelling,and atrophy of intestinal villi.Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models(occludin:0.57 ± 0.159 fold vs baseline,P = 0.000;claudin-1:0.3067 ± 0.1291 fold vs baseline,P = 0.003),as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein(occludin:0.61 ± 0.0473 fold vs baseline,P = 0.000;claudin-1:0.6633 ± 0.0328 fold vs baseline,P = 0.000).Prophylactic treatment with antiTNF-α IgG antibody prevented changes in IP(4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.791),intestinal tissue ultrastructure,and the mRNA levels of occludin and claudin-1 expression(occludin:0.8865 ± 0.0274 fold vs baseline,P = 0.505;claudin-1:0.85 ± 0.1437 fold vs baseline,P = 0.1),and in the protein levels(occludin:0.9467 ± 0.0285 fold vs baseline,P > 0.05;claudin-1:0.9533 ± 0.0186 fold vs baseline,P = 0.148).CONCLUSION:Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1,and destruction of the TJ in the colon,which were induced by TNF-α in FHF mice.
基金supports provided by the National Key Basic Research and Development Program of China (No. 2011CB201205)the National Natural Science Foundation of China (No. 51074161)the Independent research of State Key Laboratory of Coal Resources and Mine Safety of China University of Mining & Technology (No. SKLCRSM08X03)
文摘Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability increase.Slotting the seam by auxiliary drilling with a water jet that breaks the coal and slots the coal seam during the process of retreat drilling achieves pressure relief and permeability increase.Improved efficiency of gas extraction from a field test,high gas coal seam was observed.Investigating the theory of pressure relief and permeability increase required analyzing the characteristics of the double power slotting process and the effects of coal pressure relief and permeability increase.The influence of confining pressure on coal physical properties was examined by using FLAC3D software code to simulate changes of coal stress within the tool destruction area.The double power joint drilling method was modeled.Field experiments were performed and the effects are analyzed.This research shows that there is an ''islanding effect'' in front of the joint double power drill and slotting equipment.The failure strength of the coal seam is substantially reduced within the tool destruction area.Drilling depths are increased by 72% and the diameter of the borehole is increased by 30%.The amount of powdered coal extracted from the drill head increases by 17 times when using the new method.A 30 day total flow measurement from the double power drilled and slotted bores showed that gas extraction increased by 1.3 times compared to the standard drilled bores.Gas concentrations increased from 30% to 60% and were more stable so the overall extraction efficiency increased by a factor of two times.
基金funded by a grant from the local government of Zhejiang Province for the Specially Supported Discipline of Zoology
文摘Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue (dBPI), 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 (BPIL1) and BPI like 3 (BPIL3) of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 (5) : 376 - 382, 2009].
基金provided by the National Eleventh Five-Year scientific and Technological Support Plan Subject of China (No.2007BAK29B01)the National Natural Science Foundation (No.50534090)+2 种基金the National Key Basic Research Development Program of China (No.2011CB201205)State Key Laboratory of Coal Resources and Mine Safety of China University of Mining Technology of China (No.SKLCRSM08X03)the Youth Science and Technology Fund of China University of Mining and Technology (No.JGY101605)
文摘As for the coal seam with high stress,high gas and low permeability,a single technology cannot prevent the complex dynamic disasters.Because of this,the study proposes a new method of pressure-relief and permeability-increase technology of the high liquid–solid coupling blast.Through coal seam injection and charging structure change,the paper fully works out the dual functions of the water and explosion.Using the theoretical calculation,numerical simulation and physical experiments,we obtained that the initial blasting stress,displacement and overpressure of the liquid–solid coupling blast are much better than that of ordinary blasting.The technology has been used in the relative coal mine,and the application results show that the technique has effectively prevented the coal and gas outburst,which has a wide range of application.
基金Supported by The Deanship of Scientific Research at King Saud University,through research group project,No.RGPVPP-016,entitled "Cardiovascular research Group"
文摘AIM:To investigate the effect of administration of agmatine(AGM) on gastric protection against ischemia reperfusion(I/R) injury.METHODS:Three groups of rats(6/group);sham,gastric I/R injury,and gastric I/R + AGM(100 mg/kg,i.p.given 15 min prior to gastric ischemia) were recruited.Gastric injury was conducted by ligating celiac artery for 30 min and reperfusion for another 30 min.Gastric tissues were histologically studied and immunostained with angiopoietin 1(Ang-1) and Ang-2.Vascular endothelial growth factor(VEGF) and monocyte chemoattractant protein-1(MCP-1) were measured in gastric tissue homogenate.To assess whether AKt/phosphatidyl inositol-3-kinase(PI3K) mediated the effect of AGM,an additional group was pretreated with Wortmannin(WM)(inhibitor of Akt/PI3K,15 μg/kg,i.p.),prior to ischemic injury and AGM treatment,and examined histologically and immunostained.Another set of experiments was run to study vascular permeability of the stomach using Evan's blue dye.RESULTS:AGM markedly reduced Evan's blue dye extravasation(3.58 ± 0.975 μg/stomach vs 1.175 ± 0.374 μg/stomach,P < 0.05),VEGF(36.87 ± 2.71 pg/100 mg protein vs 48.4 ± 6.53 pg/100 mg protein,P < 0.05) and MCP-1 tissue level(29.5 ± 7 pg/100 mg protein vs 41.17 ± 10.4 pg/100 mg protein,P < 0.01).It preserved gastric histology and reduced congestion.Ang-1 and Ang-2 immunostaining were reduced in stomach sections of AGM-treated animals.The administration of WM abolished the protective effects of AGM and extensive hemorrhage and ulcerations were seen.CONCLUSION:AGM protects the stomach against I/R injury by reducing vascular permeability and inflammation.This protection is possibly mediated by Akt/PI3K.
基金Supported by the grants from the National Natural Science Foundation of China(21176220,20876143,31470793)the Natural Science Foundation of Zhejiang Province(Z13B060008)the Key Technology Research and Development Project of Ningbo(2011C11023)
文摘The activity of whole-cell biocatalysts is strongly compromised by the cell envelope, which is a permeability harrier against the diffusion of substrates and products. Although common chemical or physical permeahilization methods used in cultured cells enhance cell permeability, these methods inevitably add several extra processing steps after cell cultivation, as well as impede large scale processing. To increase membrane permeability and cell- bound glutamate decarboxylase (GAD) activity of recombinant Escherichia coil (BL21 (DE3)-pET28a-gadB) cells without the need for an additional permeabilization step, we investigated the permeabilizing effects of adding cell wall synthesis inhibitors or suffactants to the culture media. Ampidllin was the most effective at improving cell-bound GAD activity of the BL21 (DE3)-pET28a-gadB, although it decreased the cell biomass yield. The best permeabilization effect was observed using an ampicillin concentration of 5 pg. ml-1. Using this concentration, the cell hiomass did decrease by 40.58%, but the cell-bound GAD activity of BL21 (DE3)-pET28a-gadB and total cell-bound GAD activity per milliliter of culture was enhanced by 6.24- and 3.64-fold, respectively. Treatment ofBL21 (DE3)-pET28a-gadB cells with 5 tag.ml 1 ampicillin resulted in structural changes to the cell envelope, but did not substantially affect GAD expression. By entrapping the ampicillin-treated cells in an open pore gelation matrix, which is a polymer derived from polyvinyl alcohol (PVA), alginate, and boric acid, the transfor- mation rate of γ-aminobutyric acid (GABA) at the 10th cycle produced by immobilized and permeabilized cells remained 46% of the first cycle. GAD activity of the immobilized, permeabilized cells remained over 90% after 30 days of storage at 4 ℃.
基金the Shandong Provincial Science and Technology Program,No. 2006GG202004
文摘Cromakalim,an adenosine triphosphate-sensitive potassium channel opener,exhibits protective effects on cerebral ischemia/reperfusion injury.However,there is controversy as to whether this effect is associated with aquaporin-4 and blood-brain barrier permeability.Immunohistochemistry results show that preventive administration of cromakalim decreased aquaporin-4 and IgG protein expression in rats with ischemia/reperfusion injury;it also reduced blood-brain barrier permeability,and alleviated brain edema,ultimately providing neuroprotection.
文摘In normal condition, intestine mucosa possesses barrier function. When the barrier function of intestine mucosa was damaged, intestinal bacteria, endotoxin, or other substances would enter blood. It is generally accepted that biliary bacteria origins from the intestine either via duodenal papilla or intestinal mucosa. In this study, we aimed to investigate the intestinal permeability changes of cholelithiasis patients to elucidate the possible pathogenesis of cholelithiasis.
文摘Background Hypoxemia sometimes occurs in the emergency room in the patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI), even in those with administration of conventional high-flow oxygen inhalation. The objective of the present study was to evaluate the effectiveness of non-invasive ventilation (NIV) in improving blood oxygen content and hemorheology in patients with AMI and hypoxemia. Methods This prospective study enrolled 50 consecutive eligible patients with AMI (aged 72.3 ± 9.5 years), who had undergone PCI and been administered high-flow oxygen but still had hypoxemia. Blood was taken before NIV and at 0.5, 1, and 2 h after NIV. Blood gases, hemorheological variables including erythrocyte deformability, erythrocyte aggregation, erythrocyte osmotic fragility, membrane fluidity, and oxidative stress level were measured. Results Blood PaO2 increased to normal by 1 h after NIV. Assessed hemorheological variables had all improved and plasma malondialdehyde concentration decreased significantly after 2 h of NIV. Conclusions Our data suggest that NIV can help to improve blood oxygen content, hemorheological status, and minimize plasma lipid peroxidation injury in hypoxemic patients with AMI who have undergone PCI.
基金This work was supported by the National Funds for Distinguished Young Scientists of China (No. 81325009) and National Nature Science Foundation of China (No. 81270168, No. 81227901), (Feng Cao BWS12J037), Innovation Team granted by Ministry of Education PRC (IRT1053), National Basic Research Program of China (2012CB518101). Shaanxi Province Program (2013K12-02-03, 2014KCT-20). The authors declare no conflict of interest.
文摘Background The induced pluripotent stem cell (iPSC) has shown great potential in cellular therapy of myocardial infarction (MI), while its application is hampered by the low efficiency of cardiomyocyte differentiation. The present study was designed to investigate the effects of cardiotrophin-1 (CT-1) on cardiomyocyte differentiation from mouse induced pluripotent stem cells (miPSCs) and the underlying mechanisms involved. Methods The optimal treatment condition for cardiomyocyte differentiation from miPSCs was established with ideal concentration (10 ng/mL) and duration (from day 3 to day 14) of CT-1 administration. Up-regulated expression of cardiac specific genes that accounted for embryonic cardiogenesis was observed by quantitative RT-PCR. Elevated amount of a-myosin heavy chain (ct-MHC) and cardiac troponin I (cTn I) positive cells were detected by immunofluorescence staining and flow cytometry analysis in CT- 1 group. Results Transmission electron microscopic analysis revealed that cells treated with CT- 1 showed better organized sacromeric structure and more mitochondria, which are morphological characteristic of matured cardiomyocytes. Western blot demonstrated that CT-1 promotes cardiomyocyte differentiation from miPSCs partly via JAK2/STAT3/Pim-1 pathway as compared with control group. Conclusions These findings suggested that CT-1 could enhance the cardiomyocyte differentiation as well as the maturation of mouse induced pluripotent stem cell derived cardiomyocytes by regulating JAK2/STAT3/Pim-1 signaling pathway.
基金the National Science Fund for Distinguished Young Scholars of China(No.21225625)the National Natural Science Foundation of China(No.21176087)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20110172110013)
文摘Cobalt-free perovskite-type oxides BaFel_yTayO3-6 (0 _〈 y -〈 0.2) were synthesized via a simple solid state reac- tion. The cubic perovskite structure can be obtained when y is over 0.1. BaFeo.Ta0.lO3-6 (BFT0.1) membrane shows the highest oxygen permeation flux, which can reach 1.6 ml. min- 1. cm-2 at 950 ℃ under the gradient of air/He. The O2-TPD results reveal that BaFe0.9Ta0.lO3-a material shows an excellent reversibility and phase structure stability in air. The oxygen permeation flux is limited by the bulk diffusion when the membrane thick- ness is over 0.8 mm, and it is limited by both the bulk diffusion and the surface exchange when the membrane thickness is below 0.5 mm. Stable oxygen permeation fluxes are obtained during 180 h operation.
基金Supported by Drug Separation and Purification Project in Programme for Development of Novel Drug (2009ZX09301-008)the Program of Introducing Talents of Discipline to Universities (B06006)State Key Laboratory of Precision Measuring Technology and Instruments (Tianjin University)
文摘In this study, orange G dye was efficiently removed from aqueous solution by ultraflltration (UF) membrane separation enhanced with activated carbon adsorption. The powdered activated carbon (PAC) was deposited onto the UF membrane surface, forming an intact filter cake. The enhanced UF process simultaneously exploited the high water permeation flux of porous membrane and the high adsorption ability of PAC toward dye molecules. The influencing factors on the dye removal were investigated. The results indicated that with sufficient PAC incorporation, the formation of intact PAC filtration cake led to nearly complete rejection for dye solution under opti-mized dye concentration and operation pressure, without large sacnticlng the permeation tlux ot the filtration process. Typically, the dye rejection ratio increased from 43.6% for single UF without adsorption to nearly 100% for the enhanced UF process, achieving long time continuous treatment with water permeation flux of 47 L·m^-2·h^-1. The present study demonstrated that adsorption enhanced UF may be a feasible method for the dye wastewater treatment.
基金Project(12YJCZH309) supported by Humanities and Social Sciences Youth Foundation of the Ministry of Education of ChinaProject(20120041120006) supported by Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘A reliability-based stochastic system optimum congestion pricing(SSOCP) model with endogenous market penetration and compliance rate in an advanced traveler information systems(ATIS) environment was proposed. All travelers were divided into two classes. The first guided travelers were referred to as the equipped travelers who follow ATIS advice, while the second unguided travelers were referred to as the unequipped travelers and the equipped travelers who do not follow the ATIS advice(also referred to as non-complied travelers). Travelers were assumed to take travel time, congestion pricing, and travel time reliability into account when making travel route choice decisions. In order to arrive at on time, travelers needed to allow for a safety margin to their trip.The market penetration of ATIS was determined by a continuous increasing function of the information benefit, and the ATIS compliance rate of equipped travelers was given as the probability of the actually experienced travel costs of guided travelers less than or equal to those of unguided travelers. The analysis results could enhance our understanding of the effect of travel demand level and travel time reliability confidence level on the ATIS market penetration and compliance rate; and the effect of travel time perception variation of guided and unguided travelers on the mean travel cost savings(MTCS) of the equipped travelers, the ATIS market penetration, compliance rate, and the total network effective travel time(TNETT).