The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different pol...The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies.展开更多
A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-g...A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.展开更多
A novel poly-/-arginine microcapsule was prepared due to its nutritional function and pharmacological efficacy. A high-voltage electrostatic droplet generator was used to make uniform microcapsules. The results show t...A novel poly-/-arginine microcapsule was prepared due to its nutritional function and pharmacological efficacy. A high-voltage electrostatic droplet generator was used to make uniform microcapsules. The results show that the membrane strength and permeating property are both remarkably affected with the changes of sodium alginate concentration. With the sodium alginate concentration increasing, gel beads sizes increase from 233μm to 350μm, release ratio is also higher at the same time, but the membrane strength decreases.展开更多
Two-dimensional nuclear overhauser enhancement (2D NOESY)measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of ...Two-dimensional nuclear overhauser enhancement (2D NOESY)measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the. Normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.展开更多
Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. ...Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. The effects of the factors such as solvent, amount of the initiator and reaction time were investigated. The copolymers were characterized by IR, H-1-NMR, H-1{P-31}-NMR, C-13-NMR, P-31{H-1}-NMR, and DSC. High molecular weight of the copolymer and high yield of the polymerization were achieved within 3 min at 25 degrees C. The polymerization process was studied by P-31{H-1}-NMR and transesterification was found during longer polymerization time.展开更多
The interaction of poly(sodium sulfodecyl methacrylate) (PSSM) with cetyltrimethyl ammonium bromide (CTAB)was studied. It was found that the precipitate formed from PSSM and CTAB will be dissolved by excessive CTAB, r...The interaction of poly(sodium sulfodecyl methacrylate) (PSSM) with cetyltrimethyl ammonium bromide (CTAB)was studied. It was found that the precipitate formed from PSSM and CTAB will be dissolved by excessive CTAB, resultingin the appearance of two maxima of the solution viscosity at the molar ratio (CTAB/-SO_3^-) of≈ 0.68 and≈1.30,respectively. The first one is related closely to the aggregation of polymer chains via CTAB molecules and the second oneshould be ascribed to the formation of the mixed micelles comprising surfactant and the polymer's hydrophobic chains. Theeffect of NaCl on the viscosity, the transmittance of the aqueous solution and the solubility of oil-soluble dye (dimethyl yellow) in the mixed system were also investigated.展开更多
Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficac...Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80~120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy.展开更多
Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS), then irradiated by Co γ-rays at 25℃. The effects of reaction 60...Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS), then irradiated by Co γ-rays at 25℃. The effects of reaction 60 time,absorbed dose, dose-rate, inhibitor and monomer concentration on the grafting yield were studied. Grafting yields of both AA and SSS onto FEP, respectively, increase with irradiation dose, but some saturation will appear at high dose and monomer concentration. The grafting yield increases with reaction time and then levels off. The graft- ing of SSS onto FEP is more difficult than the grafting of AA. The analysis of grafted membranes using DSC and FT-IR have been done.展开更多
Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,...Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3^-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.展开更多
In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membrane...In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and their performance was examined by varying experimental parameters such as feed composition (0 - 100 wt%), operating temperature (30℃ - 50℃) and membrane thickness (30 - 90 micrometer (μm)). Blending NaAlg with PVP, decreased separation factor whereas increased the permeation rate as the permeation temperature was increased in Vapor Permeation (VP) and Vapor Permeation with Temperature Difference (TDVP) methods. In the TDVP method, the separation factors increased and the permeation rates decreased as the temperature of the membrane surrounding is decreased. The highest separation factor of 60 was obtained in TDVP method for 90 wt% DMF concentration in the feed.展开更多
AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium(DSS)-induced acute colitis.METHODS Thirty C57BL/6 mice were given either regular drinking ...AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium(DSS)-induced acute colitis.METHODS Thirty C57BL/6 mice were given either regular drinking water(control group) or 2%(w/v) DSS drinking water(model and poly I:C groups) ad libitum for 7 d. Poly I:C was administrated subcutaneously (20 μg/mouse) 2 h prior to DSS induction in mice of the poly I:C group. Severity of colitis was evaluated by disease activity index, body weight, colon length, histology and myeloperoxidase (MPO) activity, as well as the production of proinflammatory cytokines, including tumor necrosis factor-α(TNF-α), interleukin 17(IL-17) and interferon-γ (IFN-γ). Intestinal permeability was analyzed by the fluorescein isothiocyanate labeleddextran (FITC-D) method. Ultrastructural features of the colon tissue were observed under electron microscopy. Expressions of tight junction(TJ) proteins, including zo-1, occludin and claudin-1, were measured by immunohistochemistry/immunofluorescence, Western blot and real-time quantitative polymerase chain reaction(RT-qPCR).RESULTS DSS caused significant damage to the colon tissue in the model group. Administration of poly I:C dramatically protected against DSS-induced colitis, as demonstrated by less body weight loss, lower disease activity index score, longer colon length, colonic MPO activity, and improved macroscopic and histological scores. It also ameliorated DSS-induced ultrastructural changes of the colon epithelium, as observed under scanning electron microscopy, as well as FITC-D permeability. The m RNA and protein expressions of TJ protein, zo-1, occludin and claudin-1 were also found to be significantly enhanced in the poly I:C group, as determined by immunohistochemistry/immunofluorescence, Western blot and RT-q PCR. By contrast, poly I:C pretreatment markedly reversed the DSS-induced up-regulated expressions of the inflammatory cytokines TNF-α, IL-17 and IFN-γ.CONCLUSION Our study suggested that poly I:C may protect against DSS-induced colitis through maintaining integrity of the epithelial barrier and regulating innate immune responses, which may shed light on the therapeutic potential of poly I:C in human colitis.展开更多
In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25®by using the spray drying technique. The...In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25®by using the spray drying technique. The systems obtained were characterized by Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic Laser Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The NMR <sup>13</sup>C and FTIR techniques showed that both polymers were present in the microparticles and the DSC analysis revealed a small variation in the glass transition temperature of the PCL. The XRD and SEM analyses showed that the microparticles produced were amorphous and had a concave morphology. The NT-25 nanoload reduced the microparticles’ size due to the multiple interactions formed in the hybrid nanocomposite material. Therefore, it was possible to develop microparticles by using biodegradable and biocompatible polymers, with different polarities, allowing the incorporation of hydrophilic and hydrophobic materials and enabling the inclusion of otherwise incompatible materials in the same system.展开更多
The available alkaline recovery membranes are currently dominated by polymeric materials,but they suffer from a permeation-selectivity trade-off and inferior chemical resistance.Robust two dimensional(2D) lamellar mem...The available alkaline recovery membranes are currently dominated by polymeric materials,but they suffer from a permeation-selectivity trade-off and inferior chemical resistance.Robust two dimensional(2D) lamellar membranes with sub-nanometer wide channels are promising candidates for discerning OH^(-)and other anions.Here,we report the development of alkaline recycling membranes through stacking MoS_(2) nanosheets.Benefiting from the ordered and narrow 2D channels,MoS_(2) membranes show excellent alkaline recovery performances.The OH^(-)dialysis coefficient (U_(OH)-) and separation factor (S)towards simulated OH^(-) and WO_(4)^(2-) across the 500 nm thick MoS_(2) laminates reach 6.9×10^(-3)m·h^(-1)and 34.3 respectively.Furthermore,the chemical environments of MoS_(2) laminates were modulated by intercalating ionic poly(sodium 4-styrene sulfonate)(PSS@MoS_(2)).The U_(OH)-and S values of PSS@MoS_(2) membrane further improve to 11.7×10^(-3)m·h^(-1)and 49.8 respectively.Besides,both MoS_(2) and PSS@MoS_(2) membranes exhibit promising stability.展开更多
文摘The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies.
基金This work was supported by National Natural Science Foundation of China (No. 29504029).
文摘A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.
文摘A novel poly-/-arginine microcapsule was prepared due to its nutritional function and pharmacological efficacy. A high-voltage electrostatic droplet generator was used to make uniform microcapsules. The results show that the membrane strength and permeating property are both remarkably affected with the changes of sodium alginate concentration. With the sodium alginate concentration increasing, gel beads sizes increase from 233μm to 350μm, release ratio is also higher at the same time, but the membrane strength decreases.
文摘Two-dimensional nuclear overhauser enhancement (2D NOESY)measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the. Normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.
基金Supported by the National Natural Science Foundation of China.
文摘Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. The effects of the factors such as solvent, amount of the initiator and reaction time were investigated. The copolymers were characterized by IR, H-1-NMR, H-1{P-31}-NMR, C-13-NMR, P-31{H-1}-NMR, and DSC. High molecular weight of the copolymer and high yield of the polymerization were achieved within 3 min at 25 degrees C. The polymerization process was studied by P-31{H-1}-NMR and transesterification was found during longer polymerization time.
基金This work was supported by the National Natural Science Foundation of China (Contract No: 39870227 & 50173002).
文摘The interaction of poly(sodium sulfodecyl methacrylate) (PSSM) with cetyltrimethyl ammonium bromide (CTAB)was studied. It was found that the precipitate formed from PSSM and CTAB will be dissolved by excessive CTAB, resultingin the appearance of two maxima of the solution viscosity at the molar ratio (CTAB/-SO_3^-) of≈ 0.68 and≈1.30,respectively. The first one is related closely to the aggregation of polymer chains via CTAB molecules and the second oneshould be ascribed to the formation of the mixed micelles comprising surfactant and the polymer's hydrophobic chains. Theeffect of NaCl on the viscosity, the transmittance of the aqueous solution and the solubility of oil-soluble dye (dimethyl yellow) in the mixed system were also investigated.
基金supported by National Natural Science Foundation of China (No. 51373168)
文摘Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80~120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy.
基金Supported partially by Exploration Project of Knowledge Innovation Program of the Chinese Academy of Sciences (No.55180219)
文摘Poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) films were immersed in aqueous solution of acrylic acid (AA) and sodium styrene sulfonate (SSS), then irradiated by Co γ-rays at 25℃. The effects of reaction 60 time,absorbed dose, dose-rate, inhibitor and monomer concentration on the grafting yield were studied. Grafting yields of both AA and SSS onto FEP, respectively, increase with irradiation dose, but some saturation will appear at high dose and monomer concentration. The grafting yield increases with reaction time and then levels off. The graft- ing of SSS onto FEP is more difficult than the grafting of AA. The analysis of grafted membranes using DSC and FT-IR have been done.
基金Contract grant sponsor:Key Laboratory of Radiation Physics and Technology of Education Ministry (No.2000-03)
文摘Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3^-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.
基金Gazi University Research Fund for the support of this study.
文摘In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and their performance was examined by varying experimental parameters such as feed composition (0 - 100 wt%), operating temperature (30℃ - 50℃) and membrane thickness (30 - 90 micrometer (μm)). Blending NaAlg with PVP, decreased separation factor whereas increased the permeation rate as the permeation temperature was increased in Vapor Permeation (VP) and Vapor Permeation with Temperature Difference (TDVP) methods. In the TDVP method, the separation factors increased and the permeation rates decreased as the temperature of the membrane surrounding is decreased. The highest separation factor of 60 was obtained in TDVP method for 90 wt% DMF concentration in the feed.
基金the Scientific Research Foundation of HealthDepartment of Hebei Province,No.20160483
文摘AIM To investigate potential effects of poly I:C on mucosal injury and epithelial barrier disruption in dextran sulfate sodium(DSS)-induced acute colitis.METHODS Thirty C57BL/6 mice were given either regular drinking water(control group) or 2%(w/v) DSS drinking water(model and poly I:C groups) ad libitum for 7 d. Poly I:C was administrated subcutaneously (20 μg/mouse) 2 h prior to DSS induction in mice of the poly I:C group. Severity of colitis was evaluated by disease activity index, body weight, colon length, histology and myeloperoxidase (MPO) activity, as well as the production of proinflammatory cytokines, including tumor necrosis factor-α(TNF-α), interleukin 17(IL-17) and interferon-γ (IFN-γ). Intestinal permeability was analyzed by the fluorescein isothiocyanate labeleddextran (FITC-D) method. Ultrastructural features of the colon tissue were observed under electron microscopy. Expressions of tight junction(TJ) proteins, including zo-1, occludin and claudin-1, were measured by immunohistochemistry/immunofluorescence, Western blot and real-time quantitative polymerase chain reaction(RT-qPCR).RESULTS DSS caused significant damage to the colon tissue in the model group. Administration of poly I:C dramatically protected against DSS-induced colitis, as demonstrated by less body weight loss, lower disease activity index score, longer colon length, colonic MPO activity, and improved macroscopic and histological scores. It also ameliorated DSS-induced ultrastructural changes of the colon epithelium, as observed under scanning electron microscopy, as well as FITC-D permeability. The m RNA and protein expressions of TJ protein, zo-1, occludin and claudin-1 were also found to be significantly enhanced in the poly I:C group, as determined by immunohistochemistry/immunofluorescence, Western blot and RT-q PCR. By contrast, poly I:C pretreatment markedly reversed the DSS-induced up-regulated expressions of the inflammatory cytokines TNF-α, IL-17 and IFN-γ.CONCLUSION Our study suggested that poly I:C may protect against DSS-induced colitis through maintaining integrity of the epithelial barrier and regulating innate immune responses, which may shed light on the therapeutic potential of poly I:C in human colitis.
文摘In this study, nanostructured microparticles was developed with polycaprolactone (PCL), poly(vinyl alcohol) (PVAL) and nanoparticles of the commercial sodium clay NT-25®by using the spray drying technique. The systems obtained were characterized by Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Dynamic Laser Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The NMR <sup>13</sup>C and FTIR techniques showed that both polymers were present in the microparticles and the DSC analysis revealed a small variation in the glass transition temperature of the PCL. The XRD and SEM analyses showed that the microparticles produced were amorphous and had a concave morphology. The NT-25 nanoload reduced the microparticles’ size due to the multiple interactions formed in the hybrid nanocomposite material. Therefore, it was possible to develop microparticles by using biodegradable and biocompatible polymers, with different polarities, allowing the incorporation of hydrophilic and hydrophobic materials and enabling the inclusion of otherwise incompatible materials in the same system.
基金partially supported by the National Key Research and Development Program of China (2022YFB3805102)the National Natural Science Foundation of China (22278105, 21978062)。
文摘The available alkaline recovery membranes are currently dominated by polymeric materials,but they suffer from a permeation-selectivity trade-off and inferior chemical resistance.Robust two dimensional(2D) lamellar membranes with sub-nanometer wide channels are promising candidates for discerning OH^(-)and other anions.Here,we report the development of alkaline recycling membranes through stacking MoS_(2) nanosheets.Benefiting from the ordered and narrow 2D channels,MoS_(2) membranes show excellent alkaline recovery performances.The OH^(-)dialysis coefficient (U_(OH)-) and separation factor (S)towards simulated OH^(-) and WO_(4)^(2-) across the 500 nm thick MoS_(2) laminates reach 6.9×10^(-3)m·h^(-1)and 34.3 respectively.Furthermore,the chemical environments of MoS_(2) laminates were modulated by intercalating ionic poly(sodium 4-styrene sulfonate)(PSS@MoS_(2)).The U_(OH)-and S values of PSS@MoS_(2) membrane further improve to 11.7×10^(-3)m·h^(-1)and 49.8 respectively.Besides,both MoS_(2) and PSS@MoS_(2) membranes exhibit promising stability.