The application of amino acid-based surfactant in dishwasher detergent was studied in this paper. The foam and oil-removing performance of amino acid surfactants in alkaline condition were test to discuss feasibility ...The application of amino acid-based surfactant in dishwasher detergent was studied in this paper. The foam and oil-removing performance of amino acid surfactants in alkaline condition were test to discuss feasibility of amino acid-based surfactant from natural origin as the alternative to traditional nonionic surfactants from petroleum origin in dishwasher detergent. Comparative study was conducted through using various amino acid-based surfactants and nonionic surfactants respectively, together with enzymes and peroxide to formulate dishwasher detergents, and their application properties such as foam performance and detergency were also evaluated when washing different tableware in automatic dishwasher. The results showed that among all tested amino acid surfactants, glutamate surfactants showed low foaming and high oil-removing ability in alkaline condition, and excellent decontamination ability in dishwashing tests.展开更多
Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-...Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-Vis absorption and fluorescence spectral characteristics of these compounds in methanol were investigated. Their fluorescence emission spectra in different polarity solvents were further evaluated. Fluorescent properties and structural relationship of the compounds showed that fluorescence intensity and quantum yield inversely increase with the non-coplanar degree. In addition, the solvent polarity has different effects on the fluorescence emission spectra of two compounds.展开更多
In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various...In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various nucleic acid-based therapeutic approaches targeting the HCV genome,such as ribozymes,aptamers,siRNAs,and antisense oligonucleotides,have been suggested as potential tools against HCV.Nucleic acids are potentially immunogenic and typically require a delivery tool to be utilized as therapeutics.These limitations have hampered the clinical development of nucleic acid-based therapeutics.However,despite these limitations,nucleic acid-based therapeutics has clinical value due to their great specificity,easy and large-scale synthesis with chemical methods,and pharmaceutical flexibility.Moreover,nucleic acid therapeutics are expected to broaden the range of targetable molecules essential for the HCV replication cycle,and therefore they may prove to be more effective than existing therapeutics,such as interferon-αand ribavirin combination therapy.This review focuses on the current status and future prospects of ribozymes,aptamers,siRNAs,and antisense oligonucleotides as therapeutic reagents against HCV.展开更多
With more and more lithium-ion batteries(LIBs)being put into production and application,precious metals such as lithium and cobalt are scarce,so it is imminent to recover various strategic metal resources from spent L...With more and more lithium-ion batteries(LIBs)being put into production and application,precious metals such as lithium and cobalt are scarce,so it is imminent to recover various strategic metal resources from spent LIBs.Meanwhile,the complex and difficult problem of separating and recovering metals from leaching solutions has been an urgent question that needs to be resolved.In this work,a phosphoric acid-based deep eutectic solvent(DES)was developed for extracting metals from spent LIBs and one-step selectively separating and efficiently recovering transition metal.The prepared DES shows excellent extraction performance for Li(100%)and Co(92.8%)at 100°C.In addition,the extraction system can effectively separate and precipitate Co through its own components,avoiding the introduction of new precipitants and the destruction of the original composition structure of DES.This also contributes to the good cycle stability of the extraction system with excellent extraction performance for Li(94.3%)and Co(80.8%)after 5 cycles.This work proposes a green method for one-step selectively separating and recovering valuable metals from spent LIBs.展开更多
Infectious diseases,mostly caused by bacteria and viruses but also a result of fungal and parasitic infection,have been one of the most important public health concerns throughout human history.The first step in comba...Infectious diseases,mostly caused by bacteria and viruses but also a result of fungal and parasitic infection,have been one of the most important public health concerns throughout human history.The first step in combating these pathogens is to get a timely and accurate diagnosis at an affordable cost.Many kinds of diagnostics have been developed,such as pathogen culture,biochemical tests and serological tests,to help detect and fight against the causative agents of diseases.However,these diagnostic tests are generally unsatisfactory because they are not particularly sensitive and specific and are unable to deliver speedy results.Nucleic acid-based diagnostics,detecting pathogens through the identification of their genomic sequences,have shown promise to overcome the above limitations and become more widely adopted in clinical tests.Here we review some of the most popular nucleic acid-based diagnostics and focus on their adaptability and applicability to routine clinical usage.We also compare and contrast the characteristics of different types of nucleic acid-based diagnostics.展开更多
A series of dehydroabietic acid-based diarylamines have been synthesized in order to investigate their fluorescent properties, photostability, cell toxicity and in vitro fluorescence imaging. The geometries as well as...A series of dehydroabietic acid-based diarylamines have been synthesized in order to investigate their fluorescent properties, photostability, cell toxicity and in vitro fluorescence imaging. The geometries as well as their molecular properties were optimized at the B3LYP/6-31G~* level using Gaussian 03. The results indicate that molecular geometry, HOMO and LUMO energies, and energy gaps are important to predict absorption and fluorescent properties. Five of the compounds can be effectively taken up by human cervical carcinoma, human hepatocellular carcinoma SMMC-7721, human gastric cancer SGC-7901 and human lung adenocarcinoma A549 cells and strong blue fluorescent signals are detected in these cells. These compounds are potential candidates for fluorescent probes in biological diagnosis.展开更多
The more than three decades of research in nucleic acid nanotechnology has led to the thrilling progress in rationally designed structures and artificial molecular devices with programmable functions and various appli...The more than three decades of research in nucleic acid nanotechnology has led to the thrilling progress in rationally designed structures and artificial molecular devices with programmable functions and various applications.Nucleic acid–based aggregates feature precise molecular recognition and sequence programmability,versatility,as well as marked biocompatibility,providing promising candidates for biomedical applications.In this minireview,we summarize the recent,successful efforts to construct and employ nucleic acid–based aggregates for biomedical applications,including drug delivery,bioimaging,biosensing,cell analysis,and combined cancer therapy.We also discuss the remaining challenges and opportunities in the field.展开更多
Perivascular delivery of therapeutic agents against established aetiologies for occlusive vascular remodelling has great therapeutic potential for vein graft failure.However,none of the perivascular drug delivery syst...Perivascular delivery of therapeutic agents against established aetiologies for occlusive vascular remodelling has great therapeutic potential for vein graft failure.However,none of the perivascular drug delivery systems tested experimentally have been translated into clinical practice.In this study,we established a novel strategy to locally and sustainably deliver the cyclin-dependent kinase 8/19 inhibitor Senexin A(SenA),an emerging drug candidate to treat occlusive vascular disease,using graphene oxide-hybridised hyaluronic acid-based hydrogels.We demonstrated an approach to accommodate SenA in hyaluronic acid-based hydrogels through utilising graphene oxide nanosheets allowing for non-covalent interaction with SenA.The resulting hydrogels produced sustained delivery of SenA over 21 days with tunable release kinetics.In vitro assays also demonstrated that the hydrogels were biocompatible.This novel graphene oxide-incorporated hyaluronic acid hydrogel offers an optimistic outlook as a perivascular drug delivery system for treating occlusive vascular diseases,such as vein graft failure.展开更多
K-struvite was prepared by precipitation method,and the stability of K-struvite in high temperature and acid-base environment were investigated by X-ray diffraction(XRD),thermogravimetric analysis(TG/DSC),and infrared...K-struvite was prepared by precipitation method,and the stability of K-struvite in high temperature and acid-base environment were investigated by X-ray diffraction(XRD),thermogravimetric analysis(TG/DSC),and infrared spectroscopy(FT-IR).The results show that K-struvite decomposes from 50 to 110℃,and the mass loss begins at 50℃before being completely destroyed at 110℃,then further heating at temperature above 500℃leading to complete loss of the binding water in K-struvite.Moreover,K-struvite is more stable in alkaline environments than acidic environment.展开更多
Acid-Base Indicator, Turmeric Rhizome (Curcuma longa) was extracted from the root of a turmeric plant. The turmeric was peeled, washed and dried in an oven at 60°C. It was ground into powder and soaked in hot ...Acid-Base Indicator, Turmeric Rhizome (Curcuma longa) was extracted from the root of a turmeric plant. The turmeric was peeled, washed and dried in an oven at 60°C. It was ground into powder and soaked in hot and cold ethanol for the extraction. The extract was filtered and part of it was concentrated to yield a reasonable quantity of turmeric indicator. On standardization of acid with a base, 0.05 M base respectively of Sodium hydroxide (NaOH), sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>) and Disodium borate (B<sub>4</sub>Na<sub>2</sub>O<sub>7</sub>) were used. Hot and cold extracts of turmeric were used as indicators and were compared with methyl orange and phenolphthalein. On the preliminary test carried out, hot and cold turmeric indicator showed yellow colour in acid medium and orange colour in the base. Methyl orange showed red colour in acid but yellow in the base, phenolphthalein was colourless in acid but pink in the base. During titration there were colour changes at the end points in the entire test carried out. The average volumes at ends points were calculated, the molar concentrations and mass concentrations of the acids used were also determined. The results showed that there was no difference between the natural indicators used and the existing synthetic indicators which are toxic to our environment.展开更多
Developing the sensitive point-of-care testing(POCT)of oncogenic nucleic acids from human papillomavirus(HPV)infection is essential in preventing cervical can-cer,especially in resource-limited settings.Rolling circle...Developing the sensitive point-of-care testing(POCT)of oncogenic nucleic acids from human papillomavirus(HPV)infection is essential in preventing cervical can-cer,especially in resource-limited settings.Rolling circle amplification(RCA)is attractive in achieving POCT via nucleic acid-based aggregation under isothermal conditions.However,the influence of RCA product structure on the aggregation remains unexplored resulting in limited sensitivity.Here,a minimum secondary structured RCA technique(MSS-RCA)is developed by designing a unique circu-lar template,demonstrating significantly enhanced detection sensitivity with only one amplification step and one primer under isothermal conditions.The amplifi-cation efficiency of MSS-RCA could be kinetically manipulated by controlling the secondary structure of the circular template.Introducing the invertase probe to MSS-RCA,HPV16 E6/E7 nucleic acid target was detected with a personal glucose meter(PGM)with a sensitivity of 5 fM(50 zmol in 10µL).This integrated MSS-RCA-PGM detection system was successfully applied to detect HPV16 E6/E7 mRNA extracted from 54 cervical swab samples reaching a positive predictive value of 100.00%and negative predictive values of 96.00%(77.77%to 99.40%,95%CI).MSS-RCA-PGM provides a sensitive POCT platform for the detection of nucleic acid biomarkers for screening of cervical cancer or other diseases.展开更多
Metformin is a common diabetes drug that may reduce lactate clearance by inhibiting mitochondrial oxidative phosphorylation,leading to metforminassociated lactic acidosis(MALA).As diabetes mellitus is a common chronic...Metformin is a common diabetes drug that may reduce lactate clearance by inhibiting mitochondrial oxidative phosphorylation,leading to metforminassociated lactic acidosis(MALA).As diabetes mellitus is a common chronic metabolic condition found in critically ill patients,pre-existing metformin use can often be found in critically ill patients admitted to the intensive care unit or the high dependency unit.The aim of this narrative mini review is therefore to update clinicians about MALA,and to provide a practical approach to its diagnosis and treatment.MALA in critically ill patients may be suspected in a patient who has received metformin and who has a high anion gap metabolic acidosis,and confirmed when lactate exceeds 5 mmol/L.Risk factors include those that reduce renal elimination of metformin(renal impairment from any cause,histamine-2 receptor antagonists,ribociclib)and excessive alcohol consumption(as ethanol oxidation consumes nicotinamide adenine dinucleotides that are also required for lactate metabolism).Treatment of MALA involves immediate cessation of metformin,supportive management,treating other concurrent causes of lactic acidosis like sepsis,and treating any coexisting diabetic ketoacidosis.Severe MALA requires extracorporeal removal of metformin with either intermittent hemodialysis or continuous kidney replacement therapy.The optimal time to restart metformin has not been well-studied.It is nonetheless reasonable to first ensure that lactic acidosis has resolved,and then recheck the kidney function post-recovery from critical illness,ensuring that the estimated glomerular filtration rate is 30 mL/min/1.73 m^(2) or better before restarting metformin.展开更多
BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution th...BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis techniques.In a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital stay.AIM To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor outcomes.METHODS This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography scan.Laboratory and clinical data were obtained from electronic records.Categorical variables were compared using Fisher’s exact test.Continuous data were presented as median and interquartile range.The Mann-Whitney U test was used for comparisons.RESULTS In total,211 patients were analyzed.The mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus hydrogenii.Of those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory origin.The non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score 3.We did not find severe acid-base imbalance in this population.The analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not different between the groups.CONCLUSION Alkalemia is prevalent in COVID-19 patients.Although we did not find an association between acid-base variables and mortality,the use of Stewart’s methodology may provide insights into this severe disease.展开更多
Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical,...Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical, through oxidative esterification over Au-based catalysts. Detailed experimental studies showed that Au on amphoteric supports with appropriate strength and balanced ratio of acid and base sites can facilitate the desired oxidative-esterification pathway without accelerating undesired aldol-condensation or Cannizzaro reactions. In particular, hydroxyapatite (with a Ca/P ratio of 1.62) supported Au achieved 87% selectivity to methyl pyruvate at an acetol conversion of 62%.展开更多
As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in thi...As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments.展开更多
5-Hydroxymethylfurfural(5-HMF),as a key platform compound for the conversion of biomass to various biomass-derived chemicals and biofuels,has been attracted extensive attention.In this research,using Pickering high in...5-Hydroxymethylfurfural(5-HMF),as a key platform compound for the conversion of biomass to various biomass-derived chemicals and biofuels,has been attracted extensive attention.In this research,using Pickering high internal phase emulsions(Pickering HIPEs)as template and functional metal-organic frameworks(MOFs,UiO-66-SO;H and UiO-66-NH;)/Tween 85 as co-stabilizers to synthesis the dual acid-base bifunctional macroporous polymer catalyst by one-pot process,which has excellent catalytic activity in the cascade reaction of converting cellulose to 5-HMF.The effects of the emulsion parameters including the amount of surfactant(ranging from 0.5%to 2.0%(mass)),the internal phase volume fraction(ranging from 75%to 90%)and the acid/base Pickering particles mass ratio(ranging from 0:6 to 6:0)on the morphology and catalytic performance of solid catalyst were systematically researched.The results of catalytic experiments suggested that the connected large pore size of catalyst can effectively improve the cellulose conversion,and the synergistic effect of acid and base active sites can effectively improve the 5-HMF yield.The highest 5-HMF yield,about 40.5%,can be obtained by using polymer/MOFs composite as catalyst(Poly-P12,the pore size of(53.3±11.3)μm,the acid density of 1.99 mmol·g^(-1)and the base density of 1.13 mol·g^(-1))under the optimal reaction conditions(130℃,3 h).Herein,the polymer/MOFs composite with open-cell structure was prepared by the Pickering HIPEs templating method,which provided a favorable experimental basis and theoretical reference for achieving efficient production of high addedvalue product from abundant biomass.展开更多
Objective:To improve the diagnosis and therapeutic effect of occurrence and development of hyponatremia and disorder of acid-base balance among patients with hepatic encephalopathy(HE) by elucidating the regularity an...Objective:To improve the diagnosis and therapeutic effect of occurrence and development of hyponatremia and disorder of acid-base balance among patients with hepatic encephalopathy(HE) by elucidating the regularity and mechanism,as well as its influence on prognosis.Methods:327 HE patients admitted to our hospital from January 1990 to June 2010 were enrolled.Meanwhile 316 patients hospitalized in the medical department of the same hospital were chosen as the control group.Patients in both groups were given the same methods to measure arterial blood gas parameters(pH value,PaCO2,[HCO3-],TCO2,BE and SaO2),blood biochemistry([Na+],[K+],[Cl-]),liver function,kidney function and blood glucose,serum sodium,and thereupon tocalculate the anion gap(AG) and the potential [HCO3-],and acid-base balance disorder.Results:Among the 327 HE patients,hyponatremia was found in 188 cases(57.4%),of whom 132 patients died(70.2%).While among the 316 patients in control group,68 presented with hyponatremia(21.5%),and 19 died(27.9%).The incidence and mortality were significantly different between the two groups(P<0.001).All the 327 patients presented with different degrees of acid-base balance disorder and 178 died(54.4%),in whom 164(50.2%) belonged to simple acid-base balance disorder and 74(45.1%) died,136(41.6%) were dual acid-base balance disorder and 80(58.8%) died,27(8.2%) were triple acid-base disturbance and 24(88.9%) died.Whereas in the control group only 83 patients(26.2%) were recognized as simple and dual acid-base balance disorder,and 18(21.7%) died.There was higher incidence of acid-base balance disorder and mortality rate in HE group than control one(P<0.001).Conclusion:Hyponatremia is valuable to judge HE patients' prognosis.The key parameters in the judgment and evaluation on acid-base balance disorder among HE patients are the change of pH values and serum electrolyte values.When pH value ≤ 7.30 or > 7.55,it generally suggests a poor prognosis.展开更多
Cerium oxide(ceria)plays an important and fascinating role in heterogeneous catalysis as illustrated by its versatile use as a catalyst,a catalyst support,or a promotor in various oxidation and reduction reactions.Cen...Cerium oxide(ceria)plays an important and fascinating role in heterogeneous catalysis as illustrated by its versatile use as a catalyst,a catalyst support,or a promotor in various oxidation and reduction reactions.Central to these reactions is the rich defect chemistry,facile redox capability,and unusual acid-base properties of ceria.Understanding the unique redox and acid-base properties of ceria is essential to build the structure-catalysis relationship so that improved catalytic functions can be achieved for ceria-based materials.Among the characterization toolbox,spectroscopic approach indisputably stands out for its unparalleled power in offering chemical insights into the surface properties of ceria at atomic and molecular level.In this review,we summarize advances in revealing the redox and acid-base properties of ceria via a variety of spectroscopic methods including optical,X-ray,neutron,electronic and nuclear spectroscopy.Both direct spectroscopy characterization and its coupling with probe molecules are analyzed to illustrate how the nature,strength and density of different surface sites are influenced by the pretreatment,the morphology and size of ceria nanoparticles.Further directions in taking advantage of in situ/operando spectroscopy for better understanding the catalysis of ceria-based materials are proposed in the summary and outlook section.展开更多
The amphoteric properties of four sulfide minerals were characterized byacidimetric-alkalimetric titration. Chalcocite, galena, and sphalerite were found to bediprotic acids, while pyrite was determined to be a tripro...The amphoteric properties of four sulfide minerals were characterized byacidimetric-alkalimetric titration. Chalcocite, galena, and sphalerite were found to bediprotic acids, while pyrite was determined to be a triprotic acid. Intrinsic acidity con-stants for the four minerals are as follows: chalcocite-pK_(a1)=5.25, pK_(a2)=9.68;galena- pK_(a1)=5.26, pK_(a2)=9.62; sphalente- pK_(a1)= 5.08, pK_(a2)= 9.13;and pyrite - pK_(a1) = 3.50,pK_(a2)=5.32, pK_(a3)=9.81.展开更多
Sulfonated poly（phthalazinone）s （SPPENK, SPPESK and SPPBEK） were prepared by direct polymerization reaction from sulfonated monomers. The novel acid-base membranes were composed of sulfonated polymers as the acidi...Sulfonated poly（phthalazinone）s （SPPENK, SPPESK and SPPBEK） were prepared by direct polymerization reaction from sulfonated monomers. The novel acid-base membranes were composed of sulfonated polymers as the acidic compounds, and polyetherimide （PEI） as the basic compounds, casting from their N-methylpyrrolidone （NMP） solution directly onto clean glass plates at 60 ℃ aiming at enhancing membrane toughness and other relative properties. The resulted acid-base composite membranes had excellent resistance to swelling, thermo-stability, hydrolysis resistance and oxidative resistance properties with highly ion-exchange capacity （IEC）.展开更多
文摘The application of amino acid-based surfactant in dishwasher detergent was studied in this paper. The foam and oil-removing performance of amino acid surfactants in alkaline condition were test to discuss feasibility of amino acid-based surfactant from natural origin as the alternative to traditional nonionic surfactants from petroleum origin in dishwasher detergent. Comparative study was conducted through using various amino acid-based surfactants and nonionic surfactants respectively, together with enzymes and peroxide to formulate dishwasher detergents, and their application properties such as foam performance and detergency were also evaluated when washing different tableware in automatic dishwasher. The results showed that among all tested amino acid surfactants, glutamate surfactants showed low foaming and high oil-removing ability in alkaline condition, and excellent decontamination ability in dishwashing tests.
基金supported by the National Natural Science Foundation of China (No. 31170539)
文摘Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-Vis absorption and fluorescence spectral characteristics of these compounds in methanol were investigated. Their fluorescence emission spectra in different polarity solvents were further evaluated. Fluorescent properties and structural relationship of the compounds showed that fluorescence intensity and quantum yield inversely increase with the non-coplanar degree. In addition, the solvent polarity has different effects on the fluorescence emission spectra of two compounds.
基金Supported by National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning No.2012M3A9B6055200,No.2013R1A2A2A01004649
文摘In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various nucleic acid-based therapeutic approaches targeting the HCV genome,such as ribozymes,aptamers,siRNAs,and antisense oligonucleotides,have been suggested as potential tools against HCV.Nucleic acids are potentially immunogenic and typically require a delivery tool to be utilized as therapeutics.These limitations have hampered the clinical development of nucleic acid-based therapeutics.However,despite these limitations,nucleic acid-based therapeutics has clinical value due to their great specificity,easy and large-scale synthesis with chemical methods,and pharmaceutical flexibility.Moreover,nucleic acid therapeutics are expected to broaden the range of targetable molecules essential for the HCV replication cycle,and therefore they may prove to be more effective than existing therapeutics,such as interferon-αand ribavirin combination therapy.This review focuses on the current status and future prospects of ribozymes,aptamers,siRNAs,and antisense oligonucleotides as therapeutic reagents against HCV.
基金the financial support for the financial supports from the National Natural Science Foundation of China(grant Nos.21908082,22278426,21878133,and 22178154)the Natural Science Foundation of Jiangsu Province(BK20190854)+1 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent(2022ZB629)the China Postdoctoral Science Foundation(2021M701472)
文摘With more and more lithium-ion batteries(LIBs)being put into production and application,precious metals such as lithium and cobalt are scarce,so it is imminent to recover various strategic metal resources from spent LIBs.Meanwhile,the complex and difficult problem of separating and recovering metals from leaching solutions has been an urgent question that needs to be resolved.In this work,a phosphoric acid-based deep eutectic solvent(DES)was developed for extracting metals from spent LIBs and one-step selectively separating and efficiently recovering transition metal.The prepared DES shows excellent extraction performance for Li(100%)and Co(92.8%)at 100°C.In addition,the extraction system can effectively separate and precipitate Co through its own components,avoiding the introduction of new precipitants and the destruction of the original composition structure of DES.This also contributes to the good cycle stability of the extraction system with excellent extraction performance for Li(94.3%)and Co(80.8%)after 5 cycles.This work proposes a green method for one-step selectively separating and recovering valuable metals from spent LIBs.
基金supported by grants from the National Key Technology R&D Program(No.2008BAK41B01-5)the National Science and Technology Major Project—Development New Genetically Modified Organism(No.2009ZX08012-006B).
文摘Infectious diseases,mostly caused by bacteria and viruses but also a result of fungal and parasitic infection,have been one of the most important public health concerns throughout human history.The first step in combating these pathogens is to get a timely and accurate diagnosis at an affordable cost.Many kinds of diagnostics have been developed,such as pathogen culture,biochemical tests and serological tests,to help detect and fight against the causative agents of diseases.However,these diagnostic tests are generally unsatisfactory because they are not particularly sensitive and specific and are unable to deliver speedy results.Nucleic acid-based diagnostics,detecting pathogens through the identification of their genomic sequences,have shown promise to overcome the above limitations and become more widely adopted in clinical tests.Here we review some of the most popular nucleic acid-based diagnostics and focus on their adaptability and applicability to routine clinical usage.We also compare and contrast the characteristics of different types of nucleic acid-based diagnostics.
基金supported by the National Natural Science Foundation of China (31670576)Introduction of the International Advanced Forestry Science and Technology Program (20154-44)
文摘A series of dehydroabietic acid-based diarylamines have been synthesized in order to investigate their fluorescent properties, photostability, cell toxicity and in vitro fluorescence imaging. The geometries as well as their molecular properties were optimized at the B3LYP/6-31G~* level using Gaussian 03. The results indicate that molecular geometry, HOMO and LUMO energies, and energy gaps are important to predict absorption and fluorescent properties. Five of the compounds can be effectively taken up by human cervical carcinoma, human hepatocellular carcinoma SMMC-7721, human gastric cancer SGC-7901 and human lung adenocarcinoma A549 cells and strong blue fluorescent signals are detected in these cells. These compounds are potential candidates for fluorescent probes in biological diagnosis.
基金National Natural Science Foundation of China,Grant/Award Numbers:22025201,32071389,31700871,51761145044,21721002National Basic Research Program of China,Grant/Award Numbers:2016YFA0201601,2018YFA0208900+4 种基金Beijing Municipal Science&TechnologyCommission,Grant/Award Number:Z191100004819008KeyResearch Program of Frontier Sciences,CAS,Grant/Award Number:QYZDBSSW-SLH029Strategic Priority Research Program of Chinese Academy of Sciences,Grant/Award Number:XDB36000000CAS Interdisciplinary Innovation Team,and the K.C.Wong Education Foundation,Grant/Award Number:GJTD-2018-03Youth Innovation Promotion Association,CAS。
文摘The more than three decades of research in nucleic acid nanotechnology has led to the thrilling progress in rationally designed structures and artificial molecular devices with programmable functions and various applications.Nucleic acid–based aggregates feature precise molecular recognition and sequence programmability,versatility,as well as marked biocompatibility,providing promising candidates for biomedical applications.In this minireview,we summarize the recent,successful efforts to construct and employ nucleic acid–based aggregates for biomedical applications,including drug delivery,bioimaging,biosensing,cell analysis,and combined cancer therapy.We also discuss the remaining challenges and opportunities in the field.
基金The work was supported by United States NIH under the award Nos.R01 GM136877(to QW,JF),R43 HL137525(to TC),R21 EB022131(to TC),P20 GM1090991(to TC),and R01 HL160541(to TC).
文摘Perivascular delivery of therapeutic agents against established aetiologies for occlusive vascular remodelling has great therapeutic potential for vein graft failure.However,none of the perivascular drug delivery systems tested experimentally have been translated into clinical practice.In this study,we established a novel strategy to locally and sustainably deliver the cyclin-dependent kinase 8/19 inhibitor Senexin A(SenA),an emerging drug candidate to treat occlusive vascular disease,using graphene oxide-hybridised hyaluronic acid-based hydrogels.We demonstrated an approach to accommodate SenA in hyaluronic acid-based hydrogels through utilising graphene oxide nanosheets allowing for non-covalent interaction with SenA.The resulting hydrogels produced sustained delivery of SenA over 21 days with tunable release kinetics.In vitro assays also demonstrated that the hydrogels were biocompatible.This novel graphene oxide-incorporated hyaluronic acid hydrogel offers an optimistic outlook as a perivascular drug delivery system for treating occlusive vascular diseases,such as vein graft failure.
基金Funded by the National Natural Science Foundation of China(No.51972214)。
文摘K-struvite was prepared by precipitation method,and the stability of K-struvite in high temperature and acid-base environment were investigated by X-ray diffraction(XRD),thermogravimetric analysis(TG/DSC),and infrared spectroscopy(FT-IR).The results show that K-struvite decomposes from 50 to 110℃,and the mass loss begins at 50℃before being completely destroyed at 110℃,then further heating at temperature above 500℃leading to complete loss of the binding water in K-struvite.Moreover,K-struvite is more stable in alkaline environments than acidic environment.
文摘Acid-Base Indicator, Turmeric Rhizome (Curcuma longa) was extracted from the root of a turmeric plant. The turmeric was peeled, washed and dried in an oven at 60°C. It was ground into powder and soaked in hot and cold ethanol for the extraction. The extract was filtered and part of it was concentrated to yield a reasonable quantity of turmeric indicator. On standardization of acid with a base, 0.05 M base respectively of Sodium hydroxide (NaOH), sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>) and Disodium borate (B<sub>4</sub>Na<sub>2</sub>O<sub>7</sub>) were used. Hot and cold extracts of turmeric were used as indicators and were compared with methyl orange and phenolphthalein. On the preliminary test carried out, hot and cold turmeric indicator showed yellow colour in acid medium and orange colour in the base. Methyl orange showed red colour in acid but yellow in the base, phenolphthalein was colourless in acid but pink in the base. During titration there were colour changes at the end points in the entire test carried out. The average volumes at ends points were calculated, the molar concentrations and mass concentrations of the acids used were also determined. The results showed that there was no difference between the natural indicators used and the existing synthetic indicators which are toxic to our environment.
基金National Natural Science Foundation of China,Grant/Award Numbers:22174121,22211530067,T22507101802022 Natural Science Foundation of Guangdong Provincial Basic and Applied Basic Research Fund(Guangdong Hybribio)+4 种基金Shenzhen Bay Open Laboratory Fund 2021National Key Research and Development Program of China,Grant/Award Number:2020YFA0509400CUHK(SZ)-Boyalife Joint Laboratory of Regenerative Medicine Engineering FundCUHK(SZ)University Development Fund,Grant/Award Number:UDF01002012Shenzhen Key Laboratory of Functional Aggregate Materials,Grant/Award Number:ZDSYS20211021111400001。
文摘Developing the sensitive point-of-care testing(POCT)of oncogenic nucleic acids from human papillomavirus(HPV)infection is essential in preventing cervical can-cer,especially in resource-limited settings.Rolling circle amplification(RCA)is attractive in achieving POCT via nucleic acid-based aggregation under isothermal conditions.However,the influence of RCA product structure on the aggregation remains unexplored resulting in limited sensitivity.Here,a minimum secondary structured RCA technique(MSS-RCA)is developed by designing a unique circu-lar template,demonstrating significantly enhanced detection sensitivity with only one amplification step and one primer under isothermal conditions.The amplifi-cation efficiency of MSS-RCA could be kinetically manipulated by controlling the secondary structure of the circular template.Introducing the invertase probe to MSS-RCA,HPV16 E6/E7 nucleic acid target was detected with a personal glucose meter(PGM)with a sensitivity of 5 fM(50 zmol in 10µL).This integrated MSS-RCA-PGM detection system was successfully applied to detect HPV16 E6/E7 mRNA extracted from 54 cervical swab samples reaching a positive predictive value of 100.00%and negative predictive values of 96.00%(77.77%to 99.40%,95%CI).MSS-RCA-PGM provides a sensitive POCT platform for the detection of nucleic acid biomarkers for screening of cervical cancer or other diseases.
文摘Metformin is a common diabetes drug that may reduce lactate clearance by inhibiting mitochondrial oxidative phosphorylation,leading to metforminassociated lactic acidosis(MALA).As diabetes mellitus is a common chronic metabolic condition found in critically ill patients,pre-existing metformin use can often be found in critically ill patients admitted to the intensive care unit or the high dependency unit.The aim of this narrative mini review is therefore to update clinicians about MALA,and to provide a practical approach to its diagnosis and treatment.MALA in critically ill patients may be suspected in a patient who has received metformin and who has a high anion gap metabolic acidosis,and confirmed when lactate exceeds 5 mmol/L.Risk factors include those that reduce renal elimination of metformin(renal impairment from any cause,histamine-2 receptor antagonists,ribociclib)and excessive alcohol consumption(as ethanol oxidation consumes nicotinamide adenine dinucleotides that are also required for lactate metabolism).Treatment of MALA involves immediate cessation of metformin,supportive management,treating other concurrent causes of lactic acidosis like sepsis,and treating any coexisting diabetic ketoacidosis.Severe MALA requires extracorporeal removal of metformin with either intermittent hemodialysis or continuous kidney replacement therapy.The optimal time to restart metformin has not been well-studied.It is nonetheless reasonable to first ensure that lactic acidosis has resolved,and then recheck the kidney function post-recovery from critical illness,ensuring that the estimated glomerular filtration rate is 30 mL/min/1.73 m^(2) or better before restarting metformin.
文摘BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis techniques.In a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital stay.AIM To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor outcomes.METHODS This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography scan.Laboratory and clinical data were obtained from electronic records.Categorical variables were compared using Fisher’s exact test.Continuous data were presented as median and interquartile range.The Mann-Whitney U test was used for comparisons.RESULTS In total,211 patients were analyzed.The mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus hydrogenii.Of those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory origin.The non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score 3.We did not find severe acid-base imbalance in this population.The analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not different between the groups.CONCLUSION Alkalemia is prevalent in COVID-19 patients.Although we did not find an association between acid-base variables and mortality,the use of Stewart’s methodology may provide insights into this severe disease.
基金supported by the National Natural Science Foundation of China(91545114,91545203,and 21576227)the 985 Program of the Chemistry and Chemical Engineering disciplines of Xiamen University~~
文摘Acetol is a major light oxygenate and readily produced from staged or fast pyrolysis of lignocellulose biomass. Herein we report that acetol can be selectively converted to methyl pyruvate, an important fine chemical, through oxidative esterification over Au-based catalysts. Detailed experimental studies showed that Au on amphoteric supports with appropriate strength and balanced ratio of acid and base sites can facilitate the desired oxidative-esterification pathway without accelerating undesired aldol-condensation or Cannizzaro reactions. In particular, hydroxyapatite (with a Ca/P ratio of 1.62) supported Au achieved 87% selectivity to methyl pyruvate at an acetol conversion of 62%.
基金the support of Key Laboratory of Chinese Medicine Preparation of Solid Dispersion,Gansu Longshenrongfa Pharmaceutical Industry Co.,Ltd.,Gansu Province,China
文摘As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments.
基金financially supported by the National Natural Science Foundation of China(No.21606100)the Natural Science Foundation of Jiangsu Province(No.BK20180850)+1 种基金the China Postdoctoral Science Foundation(Nos.2019M651740 and 2019T120397)the Young Talent Cultivate Programme of Jiangsu University。
文摘5-Hydroxymethylfurfural(5-HMF),as a key platform compound for the conversion of biomass to various biomass-derived chemicals and biofuels,has been attracted extensive attention.In this research,using Pickering high internal phase emulsions(Pickering HIPEs)as template and functional metal-organic frameworks(MOFs,UiO-66-SO;H and UiO-66-NH;)/Tween 85 as co-stabilizers to synthesis the dual acid-base bifunctional macroporous polymer catalyst by one-pot process,which has excellent catalytic activity in the cascade reaction of converting cellulose to 5-HMF.The effects of the emulsion parameters including the amount of surfactant(ranging from 0.5%to 2.0%(mass)),the internal phase volume fraction(ranging from 75%to 90%)and the acid/base Pickering particles mass ratio(ranging from 0:6 to 6:0)on the morphology and catalytic performance of solid catalyst were systematically researched.The results of catalytic experiments suggested that the connected large pore size of catalyst can effectively improve the cellulose conversion,and the synergistic effect of acid and base active sites can effectively improve the 5-HMF yield.The highest 5-HMF yield,about 40.5%,can be obtained by using polymer/MOFs composite as catalyst(Poly-P12,the pore size of(53.3±11.3)μm,the acid density of 1.99 mmol·g^(-1)and the base density of 1.13 mol·g^(-1))under the optimal reaction conditions(130℃,3 h).Herein,the polymer/MOFs composite with open-cell structure was prepared by the Pickering HIPEs templating method,which provided a favorable experimental basis and theoretical reference for achieving efficient production of high addedvalue product from abundant biomass.
文摘Objective:To improve the diagnosis and therapeutic effect of occurrence and development of hyponatremia and disorder of acid-base balance among patients with hepatic encephalopathy(HE) by elucidating the regularity and mechanism,as well as its influence on prognosis.Methods:327 HE patients admitted to our hospital from January 1990 to June 2010 were enrolled.Meanwhile 316 patients hospitalized in the medical department of the same hospital were chosen as the control group.Patients in both groups were given the same methods to measure arterial blood gas parameters(pH value,PaCO2,[HCO3-],TCO2,BE and SaO2),blood biochemistry([Na+],[K+],[Cl-]),liver function,kidney function and blood glucose,serum sodium,and thereupon tocalculate the anion gap(AG) and the potential [HCO3-],and acid-base balance disorder.Results:Among the 327 HE patients,hyponatremia was found in 188 cases(57.4%),of whom 132 patients died(70.2%).While among the 316 patients in control group,68 presented with hyponatremia(21.5%),and 19 died(27.9%).The incidence and mortality were significantly different between the two groups(P<0.001).All the 327 patients presented with different degrees of acid-base balance disorder and 178 died(54.4%),in whom 164(50.2%) belonged to simple acid-base balance disorder and 74(45.1%) died,136(41.6%) were dual acid-base balance disorder and 80(58.8%) died,27(8.2%) were triple acid-base disturbance and 24(88.9%) died.Whereas in the control group only 83 patients(26.2%) were recognized as simple and dual acid-base balance disorder,and 18(21.7%) died.There was higher incidence of acid-base balance disorder and mortality rate in HE group than control one(P<0.001).Conclusion:Hyponatremia is valuable to judge HE patients' prognosis.The key parameters in the judgment and evaluation on acid-base balance disorder among HE patients are the change of pH values and serum electrolyte values.When pH value ≤ 7.30 or > 7.55,it generally suggests a poor prognosis.
文摘Cerium oxide(ceria)plays an important and fascinating role in heterogeneous catalysis as illustrated by its versatile use as a catalyst,a catalyst support,or a promotor in various oxidation and reduction reactions.Central to these reactions is the rich defect chemistry,facile redox capability,and unusual acid-base properties of ceria.Understanding the unique redox and acid-base properties of ceria is essential to build the structure-catalysis relationship so that improved catalytic functions can be achieved for ceria-based materials.Among the characterization toolbox,spectroscopic approach indisputably stands out for its unparalleled power in offering chemical insights into the surface properties of ceria at atomic and molecular level.In this review,we summarize advances in revealing the redox and acid-base properties of ceria via a variety of spectroscopic methods including optical,X-ray,neutron,electronic and nuclear spectroscopy.Both direct spectroscopy characterization and its coupling with probe molecules are analyzed to illustrate how the nature,strength and density of different surface sites are influenced by the pretreatment,the morphology and size of ceria nanoparticles.Further directions in taking advantage of in situ/operando spectroscopy for better understanding the catalysis of ceria-based materials are proposed in the summary and outlook section.
文摘The amphoteric properties of four sulfide minerals were characterized byacidimetric-alkalimetric titration. Chalcocite, galena, and sphalerite were found to bediprotic acids, while pyrite was determined to be a triprotic acid. Intrinsic acidity con-stants for the four minerals are as follows: chalcocite-pK_(a1)=5.25, pK_(a2)=9.68;galena- pK_(a1)=5.26, pK_(a2)=9.62; sphalente- pK_(a1)= 5.08, pK_(a2)= 9.13;and pyrite - pK_(a1) = 3.50,pK_(a2)=5.32, pK_(a3)=9.81.
基金This study was supported by the National Natural Science Foundation of China （No. 50373005）；the Chinese National Programs for High Technology Research and Development （＂863＂ plan, No. 2003AA33G030）.
文摘Sulfonated poly（phthalazinone）s （SPPENK, SPPESK and SPPBEK） were prepared by direct polymerization reaction from sulfonated monomers. The novel acid-base membranes were composed of sulfonated polymers as the acidic compounds, and polyetherimide （PEI） as the basic compounds, casting from their N-methylpyrrolidone （NMP） solution directly onto clean glass plates at 60 ℃ aiming at enhancing membrane toughness and other relative properties. The resulted acid-base composite membranes had excellent resistance to swelling, thermo-stability, hydrolysis resistance and oxidative resistance properties with highly ion-exchange capacity （IEC）.
