BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithel...BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.展开更多
The most common and aggressive type of brain tumor is glioblastoma multiforme (GBM). The prognosis for GBM remains poor with a five-year survival rate between 1% and 2%. The prospects for patients with recurrent GBM (...The most common and aggressive type of brain tumor is glioblastoma multiforme (GBM). The prognosis for GBM remains poor with a five-year survival rate between 1% and 2%. The prospects for patients with recurrent GBM (RGBM) are much worse, with the majority dying within 6 months. This publication provides a brief description of the treatment of 11 GBM patients treated with sodium phenylbutyrate (PB) in combination with pazopanib, m-TOR inhibitors, and other agents. The treatment was associated with tolerable side effects and resulted in objective responses in 54.5% of cases (complete response 18.2%, partial response 36.3%) and 27.3% cases of stable disease. The preferable treatment regimen consisted of PB, pazopanib, dasatinib, everolimus, and bevacizumab (BVZ). For various reasons not all patients were compliant with the treatment regimen. In patients who strictly complied with the treatment plan, all responded as CR or PR. Based on preliminary findings, the authors propose further phase I/II clinical trials with PB in combination with pazopanib, dasatinib, everolimus, and BVZ in patients with RGBM who failed standard surgery, radiation therapy and chemotherapy. With proper dose reductions, the treatment appears to be well-tolerated. Molecular profiling of patient subgroups with favorable genomic signatures may help to select patients for future studies.展开更多
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ...Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.展开更多
Excess water production has become an important issue in the oil and gas extraction process.Preformed particle gels(PPGs),show the capability to control the conformance and reduce excess water cut.However,conventional...Excess water production has become an important issue in the oil and gas extraction process.Preformed particle gels(PPGs),show the capability to control the conformance and reduce excess water cut.However,conventional PPGs have poor mechanical properties and their swollen particles are easily damaged by shearing force when passing through the fractures in formations,meanwhile PPGs can be also degraded into various byproducts,leading to permanent damage to the reservoir permeability after temporary plugging.Herein,a novel type of dual cross-linked PPGs(dPPGs)was designed and synthesized using sodium alginate(SA)and acrylamide(AAm),cross-linked with N,N’-methylenebisacrylamide(MBA)and Fe^(3+).Results show that dPPGs have excellent mechanical properties with a storage modulus up to 86,445 Pa,which is almost 20 times higher than other reported PPGs.Meanwhile,dPPGs can be completely degraded into liquid without any solid residues or byproducts and the viscosity of dPPGs degraded liquid was found to be lower than 5 mPa·s.A laboratory coreflooding test showed that the plugging efficiency of dPPGs was up to 99.83%on open fractures.The obtained results demonstrated that dPPGs could be used as economical and environment-friendly temporary plugging agent with high-strength,self-degradation,thermal stability,and salt stability,thus making it applicable to a wide range of conformance control to enhance oil recovery.展开更多
Colorectal cancer (CRC) is the second leading cause of cancer death related mortality with 1.2 million new cases diagnosed annually worldwide. Despite remarkable advances in the treatment of resectable CRC, advanced d...Colorectal cancer (CRC) is the second leading cause of cancer death related mortality with 1.2 million new cases diagnosed annually worldwide. Despite remarkable advances in the treatment of resectable CRC, advanced disease that recurs following initial two lines of chemotherapy, remains incurable. Targeted therapies using a single agent or in combination with other drugs have been tested in a number of clinical trials, with only moderate improvement. Here we present preliminary findings of improved overall survival (OS) using a combination of sodium phenylbutyrate with various targeted and chemotherapeutic agents in stage IV CRC patients who had failed at least two lines of chemotherapy. Results suggest a strategy of simultaneous interruption of signal transduction involving EGFR (VEGF)?KRAS-ERK and PI3K-AKT pathways and interference with cell cycle, cancer cell metabolism, maintenance of cancerous stem cells, and promotion of apoptosis. In a group of 15 patients, median OS was higher compared to other third-line therapies (14.7 months compared to between 4.8 and 9.5 months in other studies). Given the understanding that our findings are preliminary, we propose the validation of our initial results using a well-designed phase I/II trial in recurrent advanced colorectal cancer.展开更多
An aqueous solution containing sodium polyacrylate（PAAS） was used in diffusive gradient in thin-films technique（DGT） to measure DGT-labile Ni2＋ concentrations.The DGT devices（PAAS DGT） were validated in four ty...An aqueous solution containing sodium polyacrylate（PAAS） was used in diffusive gradient in thin-films technique（DGT） to measure DGT-labile Ni2＋ concentrations.The DGT devices（PAAS DGT） were validated in four types of solutions,including synthetic river water containing metal ions with complexing EDTA or that without complexing EDTA,natural river water（Ling River,Jinzhou,China） spiked with Ni2＋,and an industrial wastewater （Jinzhou,China）.Results show that only free metal ions were measured by PAAS DGT,recovery=97.36% in the solutions containing only free metal ions,recovery=49.62% in a solution with metal/EDTA molar ratio of 2：1 and recovery=0 in the solutions with metal/EDTA molar ratios of 1：1 and 1：2.These indicated that the complexes of Ni-EDTA were DGT-inert.The DGT performance in spiked river water（recovery=18.24%） and in industrial wastewater（recovery=12.25%） were investigated,which indicated that the measurement of metals by this DGT device did not include the humic substances complexed fractions of metals.The binding properties of PAAS DGT for Ni2＋ were investigated under different conditions of pH value and ionic strength.Conditional stability constants（lgK） of PAAS-Ni complexes were also evaluated.展开更多
By using the experimental approach of dropping liquid, the coupling of three anionic wetting agents with ten dust samples of sulfide ores was studied, and particularly the wetting effects of the wetting agents on the ...By using the experimental approach of dropping liquid, the coupling of three anionic wetting agents with ten dust samples of sulfide ores was studied, and particularly the wetting effects of the wetting agents on the sulfide dust influenced by factors of agent concentration and sulfate additive in the wetting agent solutions were investigated. The results show that when the solution temperature is about 20 ℃, all the selected wetting agents are effective to most dust samples, but the effect is different. Wetting agents are more effective to the dust which is difficult to be wetted. Wetting agent solution with sodium sulfate can improve the wetting ability of sulfide dust. For sodium dodecyl benzene sulfonate, the suitable concentration of sodium sulfate is 12 mmol/L. The cost of wetting agents can be reduced because the sodium sulfate is much cheaper than many surfactants. Since the dust of sulfide ores is composed of various minerals and elements, the whole effect of depressing dust should be considered while innovating a wetting agent.展开更多
In this study,a hydrophobic material,ethylcellulose,which was used as its aqueous suspension Surelease^(®),was combined with a swelling agent as the swelling layer to prepare delayed-release pellets for Danshensu...In this study,a hydrophobic material,ethylcellulose,which was used as its aqueous suspension Surelease^(®),was combined with a swelling agent as the swelling layer to prepare delayed-release pellets for Danshensu,which is a hydrophilic drug with low MW.A rupturable,delayed-release pellet consists of a drug core,a swelling layer containing a swelling agent(cross-linked sodium carboxymethyl cellulose)with a hydrophobic agent(Surelease^(®)),and a controlled layer composed by an insoluble,water-permeable polymeric coating(aqueous ethylcellulose dispersions)was developed in a fluidised bed.Results showed that blending Surelease^(®)into the swelling layer could effectively extend the release of Danshensu from the pellets,which may be attributed to the slowed swelling rate by reduction of water penetration and improvement of mechanical integrity of the swelling layer.Drug in the delayed pellets showed sustained release in beagle dogs after oral administration with comparable in-vivo exposure to the uncoated drug pellets.In conclusion,blends of hydrophobic and swelling agents in the swelling layer in doublemembrane pellets could achieve a delayed drug-release profile in vitro,as well as delayed and sustained absorption in vivo for highly soluble,low-MW drug.The present study highlighted the potential use of a delayed-release system for other hydrophilic,low-MW drugs to meet the formulation requirements for chronopharmacological diseases.展开更多
The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochem...The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochemical measurement.The results showed that both the independent and mixed additions of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7),can reduce the corrosion rate of Q235 steel in RRA containing sodium bentonite.And the inhibition effect of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7)increased with their dosage increase.With the same dosage,the inhibition efficiency of the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7),was higher than that of their independent addition.The passivation effect of Q235 steel was easy to obtain in the RRA with the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7).The optimized inhibitor for the RRA containing sodium bentonite was the mixture of Na_(2)B_(4)O_(7) and Na_(2)MoO_(4) with a total concentration of 1.5 wt.%.Furthermore,the increase in corrosion potential E_(corr) and the decrease in corrosion current density i_(cor) in carbon steel were one of the important criteria for the formation of passivation film.展开更多
Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Fact...Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Factors affecting the reductive bleaching of kaolin ore with sodium dithionite as the bleaching agent were studied and optimized to increase the whiteness of the kaolin ore from 38. 5% to about 65%. However, it was found that in the conventional bleaching process, a washing step to remove the ferrous ions from the bleached kaolin suspension was indispensable, which made the process complicated and restricted the capacity of the production. In addition, the whiteness of the bleached kaolin products was unstable. To solve the above problems, a new technique with the application of chelating agents in the bleaching process was developed to remove ferrous ions and get rid of the washing step. The bleaching process of kaolin was simplified. The whiteness of the bleached kaolin products was stabilized as well as increased to about 70%. The mechanism of the bleaching process and the action of the chelating agents were discussed.展开更多
The transport of sodium ions by erythrocytes and the plasma level of endogenous digitalis-like compound (EDLC) were assessed in 59 patients with essential hypertension before and after theadminstration of nifedipine a...The transport of sodium ions by erythrocytes and the plasma level of endogenous digitalis-like compound (EDLC) were assessed in 59 patients with essential hypertension before and after theadminstration of nifedipine and prazosin. 20 normal subjects were studied similarly and served as con-trol. It was found that (1) EH patients had a pronounced defect of both the active and passive trans-port of sodium ions by the erythrocytes; (2) a higher plasma level of EDLC was detected in EH pa-tients as compared with that of the control, but the changes of EDLC and soudium pump were notparallel; (3) after the administration of nifedipine and prazosin, the function of sodium pump wasmarkedly improved and the plasma level of EDLC decreased. In addition, the relationship betweenthe transport of sodium ions by erythrocytes and the pathogenesis of EH, and the effects of anti-hypertensive agents were discussed.展开更多
In order to improve the flow ability and early-stage strength of colloidal alumina bonded corundum castables,the colloidal alumina with 20%of solid content was used as the binder,and tabular corundum aggregates and fi...In order to improve the flow ability and early-stage strength of colloidal alumina bonded corundum castables,the colloidal alumina with 20%of solid content was used as the binder,and tabular corundum aggregates and fines,and active alumina micropowder CL370 as the main starting materials.Influences of setting accelerating agents(magnesia fines and sodium meta-aluminate)on the linear change rate,the modulus of rupture and the microstructure of corundum castables after different heat-treatments were researched.The results show(1)cement bonded corundum castables have the highest modulus of rupture after 24 h of demolding,and colloidal alumina bonded corundum castables have the lowest one;both magnesia fines and sodium meta-aluminate can improve the strength after 24 h of demolding;(2)after firing at 1000℃for 3 h,the modulus of rupture of all specimens decreases,even lower than that after 24 h of demolding;(3)after firing at 1600℃for 3 h,the castable specimen added with 0.1 mass%magnesia fines has the highest modulus of rupture;the tabular phases appear interwovenly in the specimen;(4)taking the comprehensive properties into account,0.1 mass%of magnesia fines is appropriate,and the addition of sodium meta-aluminate shall be lower than 0.3%.展开更多
Sodium alginate and gelatin are both remarkable natural biomaterials; they all have been extensively applied in tissue engineering and other relative fields,due to their low price and good biocompatibility. In this pa...Sodium alginate and gelatin are both remarkable natural biomaterials; they all have been extensively applied in tissue engineering and other relative fields,due to their low price and good biocompatibility. In this paper,we oxidized sodium alginate with sodium periodate to convert 1,2-hydroxyl groups into aldehyde groups to get aldehyde-sodium alginate( A-SA). Gelatin was modified with ethylenediamine( ED) in the presence of water-soluble1-ethyl-3( 3-dimethylaminopropyl) carbodiimide( EDC) to introduce additional amino groups to get amino-gelatin. Upon mixing the A-SA and amino-gelatin aqueous solutions together,a gel rapidly formed based on the Schiff's base reaction between the aldehyde groups in A-SA and the amino groups in amino-gelatin.Fourier transform infrared spectroscopy( FTIR) analysis confirmed the characteristic peak of Schiff's base group in the hydrogel. The gelation time measure has confirmed the gelation time is dependent on the aldehyde group content in A-SA and amino group content in amino-gelatin. The fasted hydrogel formation takes place within 30 s. The entire test suggested that this gel could be a promising candidate as soft tissue adhesive.展开更多
Objective:To compare cerumenolytic effects of docusate sodium and of 2.5%sodium bicarbonate-In vitro study;observe characteristics of the solution,using ultravioletevisible(UV/Vis)spectroscopy,and measurement of chole...Objective:To compare cerumenolytic effects of docusate sodium and of 2.5%sodium bicarbonate-In vitro study;observe characteristics of the solution,using ultravioletevisible(UV/Vis)spectroscopy,and measurement of cholesterol levels.Methods:Samples of human cerumen were mixed to form a relatively homogenous paste.Samples of about 500mg were weighed and packed at the bottom of the test tubes.To each tube was added 1.5 ml of either docusate sodium or 2.5%sodium bicarbonate.Tubes were incubated at 36.4C in a water bath for 15,30 or 60 min.Following incubation,the supernatant solution was pipetted into a cuvette.The cerumenolytic efficacy was defined as the absorbance(recorded at 350 nm and 400 nm)of the solutions.Results were the average of three replicates.A cholesterol level of each sample was then determined to confirm the result.Results:Turbidity was much greater in tubes containing 2.5%sodium bicarbonate,indicating dissolution of cerumen.Mean difference of absorbance values measured at 350 nm and 400 nm after 15,30,60 min digestions were 1.93[95%CI 1.49e2.38,p-value<0.001]and 1.81[95%CI 1.21e2.41,p-value<0.001],respectively.Furthermore,levels of cholesterol were greater in tubes containing 2.5%sodium bicarbonate solution after digestion than in tubes containing docusate sodium;11 mg/dl[95%CI 1.47e24.14,pvalue?0.083]Conclusion:Both spectrophotometric and cholesterol level assessments suggest that 2.5%sodium bicarbonate has a higher cerumenolytic effect than docusate sodium.In other words,cerumen can be dissolved in 2.5%sodium bicarbonate much better than docusate sodium in a time-dependent manner.展开更多
The present work proposes a mean for recovery of metals used in current ion-lithium batteries, like lithium, cobalt and nickel, using organic agents and ultrasound instead of the more aggressive and less environment f...The present work proposes a mean for recovery of metals used in current ion-lithium batteries, like lithium, cobalt and nickel, using organic agents and ultrasound instead of the more aggressive and less environment friendly method with sulfuric acid. This is especially useful in those countries that doesn’t have lithium deposits and have a growing demand of such batteries, reducing the economic loss this represents. During the process, variables such as temperature, leaching agent concentration and ultrasound frequency were modified, using concentrations of 0.5 M (molar), 1 M and 1.5 M of sodium citrate, temperatures of 25°C, 55°C and 60°C and also ultrasound frequencies of 20 KHz, 30 KHz and 40 KHz. It was found that the best combination of these variables that yielded the most quantity of the desired metal was 0.5 M concentration for both lithium and nickel, while using 60°C and no ultrasound with Li and 55°C and 40 KHz for Ni. For Co the best variables discovered were 1.5 molar concentration, 60°C and 40 KHz.展开更多
Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used...Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used to deliver drugs with short biological half-life and can maintain plasma levels of very potent drugs within a narrow therapeutic range for prolonged periods. In this study, cryogels have been used in a different area--transdermal controlled-release system, to obtain controlled drug release medium. For this purpose, naproxen sodium has been selected as a model drug. Naproxen, a propionic acid derivative, is a NSAID （nonsteroidal anti-inflammatory drug）. For controlled releasing of naproxen sodium, cryogels that have naproxen sodium in macropores have been prepared in sheet form for local application. Acrylamide based cryogel bands have been synthesized by flee radical cryogelation process. These cryogel bands have different pore size and includes naproxen sodium in their pores. This cryogel material has been characterized by swelling tests and SEM. Then, releasing ofnaproxen sodium from cryogels has been investigated at two different pH values, 7.4 and 5.5. According to experimental data, it has seen that these cryogel matrices that including naproxen sodium in macropores could be used in controlled drug releasing systems as bandages or other transdermal controlled releasing agents at room temperature展开更多
文摘BACKGROUND Ulcerative colitis(UC)is a chronic and debilitating inflammatory bowel disease.Cumulative evidence indicates that excess hydrogen peroxide,a potent neutrophilic chemotactic agent,produced by colonic epithelial cells has a causal role leading to infiltration of neutrophils into the colonic mucosa and subsequent development of UC.This evidence-based mechanism identifies hydrogen peroxide as a therapeutic target for reducing agents in the treatment of UC.CASE SUMMARY Presented is a 41-year-old female with a 26-year history of refractory UC.Having developed steroid dependence and never achieving complete remission on treatment by conventional and advanced therapies,she began treatment with oral R-dihydrolipoic acid(RDLA),a lipid-soluble reducing agent with intracellular site of action.Within a week,rectal bleeding ceased.She was asymptomatic for three years until a highly stressful experience,when she noticed blood in her stool.RDLA was discontinued,and she began treatment with oral sodium thiosulfate pentahydrate(STS),a reducing agent with extracellular site of action.After a week,rectal bleeding ceased,and she resumed oral RDLA and discontinued STS.To date,she remains asymptomatic with normal stool calprotectin while on RDLA.CONCLUSION STS and RDLA are reducing agents that serve as highly effective and safe therapy for the induction and maintenance of remission in UC,even in patients refractory or poorly controlled by conventional and advanced therapies.Should preliminary findings be validated by subsequent clinical trials,the use of reducing agents could potentially prevent thousands of colectomies and represent a paradigm shift in the treatment of UC.
文摘The most common and aggressive type of brain tumor is glioblastoma multiforme (GBM). The prognosis for GBM remains poor with a five-year survival rate between 1% and 2%. The prospects for patients with recurrent GBM (RGBM) are much worse, with the majority dying within 6 months. This publication provides a brief description of the treatment of 11 GBM patients treated with sodium phenylbutyrate (PB) in combination with pazopanib, m-TOR inhibitors, and other agents. The treatment was associated with tolerable side effects and resulted in objective responses in 54.5% of cases (complete response 18.2%, partial response 36.3%) and 27.3% cases of stable disease. The preferable treatment regimen consisted of PB, pazopanib, dasatinib, everolimus, and bevacizumab (BVZ). For various reasons not all patients were compliant with the treatment regimen. In patients who strictly complied with the treatment plan, all responded as CR or PR. Based on preliminary findings, the authors propose further phase I/II clinical trials with PB in combination with pazopanib, dasatinib, everolimus, and BVZ in patients with RGBM who failed standard surgery, radiation therapy and chemotherapy. With proper dose reductions, the treatment appears to be well-tolerated. Molecular profiling of patient subgroups with favorable genomic signatures may help to select patients for future studies.
基金Funded by the National Key Research and Development Program of China (No.2019YFC1906202)the Guangxi Key Research and Development Plan (Nos.Guike AA18242007-3, Guike AB19259008, and Guike AB20297014)。
文摘Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.
基金supported by Shanxi Provincial Key Research and Development Project(No.20201102002)the Science Foundation of China University of Petroleum,Beijing(No.2462020BJRC007,2462020YXZZ003)State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum(No.PRP/DX-2216)
文摘Excess water production has become an important issue in the oil and gas extraction process.Preformed particle gels(PPGs),show the capability to control the conformance and reduce excess water cut.However,conventional PPGs have poor mechanical properties and their swollen particles are easily damaged by shearing force when passing through the fractures in formations,meanwhile PPGs can be also degraded into various byproducts,leading to permanent damage to the reservoir permeability after temporary plugging.Herein,a novel type of dual cross-linked PPGs(dPPGs)was designed and synthesized using sodium alginate(SA)and acrylamide(AAm),cross-linked with N,N’-methylenebisacrylamide(MBA)and Fe^(3+).Results show that dPPGs have excellent mechanical properties with a storage modulus up to 86,445 Pa,which is almost 20 times higher than other reported PPGs.Meanwhile,dPPGs can be completely degraded into liquid without any solid residues or byproducts and the viscosity of dPPGs degraded liquid was found to be lower than 5 mPa·s.A laboratory coreflooding test showed that the plugging efficiency of dPPGs was up to 99.83%on open fractures.The obtained results demonstrated that dPPGs could be used as economical and environment-friendly temporary plugging agent with high-strength,self-degradation,thermal stability,and salt stability,thus making it applicable to a wide range of conformance control to enhance oil recovery.
文摘Colorectal cancer (CRC) is the second leading cause of cancer death related mortality with 1.2 million new cases diagnosed annually worldwide. Despite remarkable advances in the treatment of resectable CRC, advanced disease that recurs following initial two lines of chemotherapy, remains incurable. Targeted therapies using a single agent or in combination with other drugs have been tested in a number of clinical trials, with only moderate improvement. Here we present preliminary findings of improved overall survival (OS) using a combination of sodium phenylbutyrate with various targeted and chemotherapeutic agents in stage IV CRC patients who had failed at least two lines of chemotherapy. Results suggest a strategy of simultaneous interruption of signal transduction involving EGFR (VEGF)?KRAS-ERK and PI3K-AKT pathways and interference with cell cycle, cancer cell metabolism, maintenance of cancerous stem cells, and promotion of apoptosis. In a group of 15 patients, median OS was higher compared to other third-line therapies (14.7 months compared to between 4.8 and 9.5 months in other studies). Given the understanding that our findings are preliminary, we propose the validation of our initial results using a well-designed phase I/II trial in recurrent advanced colorectal cancer.
文摘An aqueous solution containing sodium polyacrylate（PAAS） was used in diffusive gradient in thin-films technique（DGT） to measure DGT-labile Ni2＋ concentrations.The DGT devices（PAAS DGT） were validated in four types of solutions,including synthetic river water containing metal ions with complexing EDTA or that without complexing EDTA,natural river water（Ling River,Jinzhou,China） spiked with Ni2＋,and an industrial wastewater （Jinzhou,China）.Results show that only free metal ions were measured by PAAS DGT,recovery=97.36% in the solutions containing only free metal ions,recovery=49.62% in a solution with metal/EDTA molar ratio of 2：1 and recovery=0 in the solutions with metal/EDTA molar ratios of 1：1 and 1：2.These indicated that the complexes of Ni-EDTA were DGT-inert.The DGT performance in spiked river water（recovery=18.24%） and in industrial wastewater（recovery=12.25%） were investigated,which indicated that the measurement of metals by this DGT device did not include the humic substances complexed fractions of metals.The binding properties of PAAS DGT for Ni2＋ were investigated under different conditions of pH value and ionic strength.Conditional stability constants（lgK） of PAAS-Ni complexes were also evaluated.
文摘By using the experimental approach of dropping liquid, the coupling of three anionic wetting agents with ten dust samples of sulfide ores was studied, and particularly the wetting effects of the wetting agents on the sulfide dust influenced by factors of agent concentration and sulfate additive in the wetting agent solutions were investigated. The results show that when the solution temperature is about 20 ℃, all the selected wetting agents are effective to most dust samples, but the effect is different. Wetting agents are more effective to the dust which is difficult to be wetted. Wetting agent solution with sodium sulfate can improve the wetting ability of sulfide dust. For sodium dodecyl benzene sulfonate, the suitable concentration of sodium sulfate is 12 mmol/L. The cost of wetting agents can be reduced because the sodium sulfate is much cheaper than many surfactants. Since the dust of sulfide ores is composed of various minerals and elements, the whole effect of depressing dust should be considered while innovating a wetting agent.
基金Financial support was provided by a research grant from the University of Macao(Research Grant RG085/09-10S/ZY/ICMS and UL016/09-Y4/CMS/WYT01/ICMS).
文摘In this study,a hydrophobic material,ethylcellulose,which was used as its aqueous suspension Surelease^(®),was combined with a swelling agent as the swelling layer to prepare delayed-release pellets for Danshensu,which is a hydrophilic drug with low MW.A rupturable,delayed-release pellet consists of a drug core,a swelling layer containing a swelling agent(cross-linked sodium carboxymethyl cellulose)with a hydrophobic agent(Surelease^(®)),and a controlled layer composed by an insoluble,water-permeable polymeric coating(aqueous ethylcellulose dispersions)was developed in a fluidised bed.Results showed that blending Surelease^(®)into the swelling layer could effectively extend the release of Danshensu from the pellets,which may be attributed to the slowed swelling rate by reduction of water penetration and improvement of mechanical integrity of the swelling layer.Drug in the delayed pellets showed sustained release in beagle dogs after oral administration with comparable in-vivo exposure to the uncoated drug pellets.In conclusion,blends of hydrophobic and swelling agents in the swelling layer in doublemembrane pellets could achieve a delayed drug-release profile in vitro,as well as delayed and sustained absorption in vivo for highly soluble,low-MW drug.The present study highlighted the potential use of a delayed-release system for other hydrophilic,low-MW drugs to meet the formulation requirements for chronopharmacological diseases.
基金support of Foundation of Science and Technology of State Grid(5216AJ20000U)Hunan Provincial Key R&D Program of China(2021GK2008).
文摘The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochemical measurement.The results showed that both the independent and mixed additions of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7),can reduce the corrosion rate of Q235 steel in RRA containing sodium bentonite.And the inhibition effect of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7)increased with their dosage increase.With the same dosage,the inhibition efficiency of the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7),was higher than that of their independent addition.The passivation effect of Q235 steel was easy to obtain in the RRA with the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7).The optimized inhibitor for the RRA containing sodium bentonite was the mixture of Na_(2)B_(4)O_(7) and Na_(2)MoO_(4) with a total concentration of 1.5 wt.%.Furthermore,the increase in corrosion potential E_(corr) and the decrease in corrosion current density i_(cor) in carbon steel were one of the important criteria for the formation of passivation film.
文摘Bleaching of the kaolin ore from Shaziling Kaolin Mine in Jiangxi Province of China was studied with the aim of enhancing the quality and value of the ore to meet the requirements from the ceramics manufacturers. Factors affecting the reductive bleaching of kaolin ore with sodium dithionite as the bleaching agent were studied and optimized to increase the whiteness of the kaolin ore from 38. 5% to about 65%. However, it was found that in the conventional bleaching process, a washing step to remove the ferrous ions from the bleached kaolin suspension was indispensable, which made the process complicated and restricted the capacity of the production. In addition, the whiteness of the bleached kaolin products was unstable. To solve the above problems, a new technique with the application of chelating agents in the bleaching process was developed to remove ferrous ions and get rid of the washing step. The bleaching process of kaolin was simplified. The whiteness of the bleached kaolin products was stabilized as well as increased to about 70%. The mechanism of the bleaching process and the action of the chelating agents were discussed.
文摘The transport of sodium ions by erythrocytes and the plasma level of endogenous digitalis-like compound (EDLC) were assessed in 59 patients with essential hypertension before and after theadminstration of nifedipine and prazosin. 20 normal subjects were studied similarly and served as con-trol. It was found that (1) EH patients had a pronounced defect of both the active and passive trans-port of sodium ions by the erythrocytes; (2) a higher plasma level of EDLC was detected in EH pa-tients as compared with that of the control, but the changes of EDLC and soudium pump were notparallel; (3) after the administration of nifedipine and prazosin, the function of sodium pump wasmarkedly improved and the plasma level of EDLC decreased. In addition, the relationship betweenthe transport of sodium ions by erythrocytes and the pathogenesis of EH, and the effects of anti-hypertensive agents were discussed.
文摘In order to improve the flow ability and early-stage strength of colloidal alumina bonded corundum castables,the colloidal alumina with 20%of solid content was used as the binder,and tabular corundum aggregates and fines,and active alumina micropowder CL370 as the main starting materials.Influences of setting accelerating agents(magnesia fines and sodium meta-aluminate)on the linear change rate,the modulus of rupture and the microstructure of corundum castables after different heat-treatments were researched.The results show(1)cement bonded corundum castables have the highest modulus of rupture after 24 h of demolding,and colloidal alumina bonded corundum castables have the lowest one;both magnesia fines and sodium meta-aluminate can improve the strength after 24 h of demolding;(2)after firing at 1000℃for 3 h,the modulus of rupture of all specimens decreases,even lower than that after 24 h of demolding;(3)after firing at 1600℃for 3 h,the castable specimen added with 0.1 mass%magnesia fines has the highest modulus of rupture;the tabular phases appear interwovenly in the specimen;(4)taking the comprehensive properties into account,0.1 mass%of magnesia fines is appropriate,and the addition of sodium meta-aluminate shall be lower than 0.3%.
基金National Natural Science Foundations of China(Nos.30973105,31271035)Shanghai Committee of Science and Technology of Nano Special,China(No.11nm0506200)Ph.D.Programs Foundation of Ministry of Education of China(No.20130075110005)
文摘Sodium alginate and gelatin are both remarkable natural biomaterials; they all have been extensively applied in tissue engineering and other relative fields,due to their low price and good biocompatibility. In this paper,we oxidized sodium alginate with sodium periodate to convert 1,2-hydroxyl groups into aldehyde groups to get aldehyde-sodium alginate( A-SA). Gelatin was modified with ethylenediamine( ED) in the presence of water-soluble1-ethyl-3( 3-dimethylaminopropyl) carbodiimide( EDC) to introduce additional amino groups to get amino-gelatin. Upon mixing the A-SA and amino-gelatin aqueous solutions together,a gel rapidly formed based on the Schiff's base reaction between the aldehyde groups in A-SA and the amino groups in amino-gelatin.Fourier transform infrared spectroscopy( FTIR) analysis confirmed the characteristic peak of Schiff's base group in the hydrogel. The gelation time measure has confirmed the gelation time is dependent on the aldehyde group content in A-SA and amino group content in amino-gelatin. The fasted hydrogel formation takes place within 30 s. The entire test suggested that this gel could be a promising candidate as soft tissue adhesive.
基金This work was supported by a grant from the Faculty of Medicine,Khon Kaen University,Thailand.
文摘Objective:To compare cerumenolytic effects of docusate sodium and of 2.5%sodium bicarbonate-In vitro study;observe characteristics of the solution,using ultravioletevisible(UV/Vis)spectroscopy,and measurement of cholesterol levels.Methods:Samples of human cerumen were mixed to form a relatively homogenous paste.Samples of about 500mg were weighed and packed at the bottom of the test tubes.To each tube was added 1.5 ml of either docusate sodium or 2.5%sodium bicarbonate.Tubes were incubated at 36.4C in a water bath for 15,30 or 60 min.Following incubation,the supernatant solution was pipetted into a cuvette.The cerumenolytic efficacy was defined as the absorbance(recorded at 350 nm and 400 nm)of the solutions.Results were the average of three replicates.A cholesterol level of each sample was then determined to confirm the result.Results:Turbidity was much greater in tubes containing 2.5%sodium bicarbonate,indicating dissolution of cerumen.Mean difference of absorbance values measured at 350 nm and 400 nm after 15,30,60 min digestions were 1.93[95%CI 1.49e2.38,p-value<0.001]and 1.81[95%CI 1.21e2.41,p-value<0.001],respectively.Furthermore,levels of cholesterol were greater in tubes containing 2.5%sodium bicarbonate solution after digestion than in tubes containing docusate sodium;11 mg/dl[95%CI 1.47e24.14,pvalue?0.083]Conclusion:Both spectrophotometric and cholesterol level assessments suggest that 2.5%sodium bicarbonate has a higher cerumenolytic effect than docusate sodium.In other words,cerumen can be dissolved in 2.5%sodium bicarbonate much better than docusate sodium in a time-dependent manner.
文摘The present work proposes a mean for recovery of metals used in current ion-lithium batteries, like lithium, cobalt and nickel, using organic agents and ultrasound instead of the more aggressive and less environment friendly method with sulfuric acid. This is especially useful in those countries that doesn’t have lithium deposits and have a growing demand of such batteries, reducing the economic loss this represents. During the process, variables such as temperature, leaching agent concentration and ultrasound frequency were modified, using concentrations of 0.5 M (molar), 1 M and 1.5 M of sodium citrate, temperatures of 25°C, 55°C and 60°C and also ultrasound frequencies of 20 KHz, 30 KHz and 40 KHz. It was found that the best combination of these variables that yielded the most quantity of the desired metal was 0.5 M concentration for both lithium and nickel, while using 60°C and no ultrasound with Li and 55°C and 40 KHz for Ni. For Co the best variables discovered were 1.5 molar concentration, 60°C and 40 KHz.
文摘Cryogels are gel matrices that have interconnected macropores and are formed in freezing-thawing systems. These interconnected macropores give elasticity to cryogels. Transdermal controlled-release systems can be used to deliver drugs with short biological half-life and can maintain plasma levels of very potent drugs within a narrow therapeutic range for prolonged periods. In this study, cryogels have been used in a different area--transdermal controlled-release system, to obtain controlled drug release medium. For this purpose, naproxen sodium has been selected as a model drug. Naproxen, a propionic acid derivative, is a NSAID （nonsteroidal anti-inflammatory drug）. For controlled releasing of naproxen sodium, cryogels that have naproxen sodium in macropores have been prepared in sheet form for local application. Acrylamide based cryogel bands have been synthesized by flee radical cryogelation process. These cryogel bands have different pore size and includes naproxen sodium in their pores. This cryogel material has been characterized by swelling tests and SEM. Then, releasing ofnaproxen sodium from cryogels has been investigated at two different pH values, 7.4 and 5.5. According to experimental data, it has seen that these cryogel matrices that including naproxen sodium in macropores could be used in controlled drug releasing systems as bandages or other transdermal controlled releasing agents at room temperature
