Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and ...Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.展开更多
In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general soluti...In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general solutions of displacements and stresses.Then,we obtain the analytical solutions of half-space and bimaterial Green’s functions.Besides,the interfacial Green’s function for bimaterials is also obtained in the analytical form.Before numerical studies,a comparative study is carried out to validate the present solutions.Typical numerical examples are performed to investigate the effects of multi-physics loadings such as the line force,the line dislocation,the line charge,and the phason line force.As a result,the coupling effect among the phonon field,the phason field,and the electric field is prominent,and the butterfly-shaped contours are characteristic in 2D PQCs.In addition,the changes of material parameters cause variations in physical quantities to a certain degree.展开更多
The combination of Ce6,an acknowledged photosensitizer,and TPL,a natural anticancer agent,has been demonstrated as a useful strategy to reinforce the tumor growth suppression,as well as decrease the systemic side effe...The combination of Ce6,an acknowledged photosensitizer,and TPL,a natural anticancer agent,has been demonstrated as a useful strategy to reinforce the tumor growth suppression,as well as decrease the systemic side effects compared with their monotherapy.However,in view of the optimal chemo-photodynamic combination efficiency,there is still short of the feasible nanovehicle to steadily co-deliver Ce6 and TPL,and stimuli-responsively burst release drugs in tumor site.Herein,we described the synergistic antitumor performance of a pH-sensitive supramolecular nanosystem,mediated by the host–guest complexing betweenβ-CD and acid pH-responsive amphiphilic co-polymer mPEG-PBAE-mPEG,showing the shell–core structural micelles with the tightβ-CD layer coating.Both Ce6 and TPLwere facilely co-loaded into the spherical supramolecular NPs(TPL+Ce6/NPs)by one-step nanoprecipitation method,with an ideal particle size(156.0 nm),acid pH-responsive drug release profile,and enhanced cellular internalization capacity.In view of the combination benefit of photodynamic therapy and chemotherapy,as well as co-encapsulation in the fabricated pH-sensitive supramolecular NPs,TPL+Ce6/NPs exhibited significant efficacy to suppress cellular proliferation,boost ROS level,lower MMP,and promote cellular apoptosis in vitro.Particularly,fluorescence imaging revealed that TPL+Ce6/NPs preferentially accumulated in the tumor tissue area,with higher intensity than that of free Ce6.As expected,upon 650-nm laser irradiation,TPL+Ce6/NPs exhibited a cascade of amplified synergistic chemo-photodynamic therapeutic benefits to suppress tumor progression in both hepatoma H22 tumor-bearingmice and B16 tumor-bearingmice.More importantly,lower systemic toxicitywas found in the tumor-bearingmice treated with TPL+Ce6/NPs.Overall,the designed supramolecular TPL+Ce6/NPs provided a promising alternative approach for chemo-photodynamic therapy in tumor treatment.展开更多
Background The well-known <pyrotherapy, of Julius Wagner-Jauregg might be the beginning of the study on the immunological concepts of schizophrenia. As the primary immune effector cells in the brain, microglia play...Background The well-known <pyrotherapy, of Julius Wagner-Jauregg might be the beginning of the study on the immunological concepts of schizophrenia. As the primary immune effector cells in the brain, microglia play a pivotal role in neuroinflammatory processes. Maternal viral infection during pregnancy is associated with an increased risk for psychiatric disorders with presumed neurodevelopmental origin, including autism spectrum disorders and schizophrenia. The present study was to quantify microglia activation in vivo in the mature offspring of rats exposed to polyriboinosinic-polyribocytidilicacid(Poly l:C) during pregnancy using 11 C'PK11195 positron emission tomography(PET) and immunohistochemistry.Objective The study aimed to quantify microglia activation in vivo in the prefrontal cortex and hippocampus in mature offspring of prenatal Poly l:C exposed rats.Methods Offspring of Poly l:C-treated dams were the model group, offspring of saline-treated dams were the control group. Behavioural test for two groups was taken by spontaneous activity, prepulse inhibition(PPI) and latent inhibition(LI) test(including active avoidance conditioning task and passive avoidance conditioning task). Randomly selected successful model rats were assessed by behavioural test in the model group and control group rats.11 C-PK11195 micro-PET/CT and immunohistochemistry were performed on the selected rats to measure microglia activation.Results The treatment group showed hyperlocomotion and deficits in PPI and LI compared with the control group. The treatment group also showed an increased11 C-PK11195 uptake ratio in the prefrontal cortex(f=-3.990, p=0.003) and hippocampus(f=-4.462,p=0.001). The number of activated microglia cells was significantly higher in the treatment group than in the control gro叩(hippocampus: f=8.204, p<0.001; prefrontal:f=6.995, p<0.001). Within the treatment group, there were significant correlations between the behavioural parameters and the activation of microglia as measured by PET and immunohistochemistry.Conclusions The present study demonstrated microglia activation in vivo in the prefrontal cortex and hippocampus in mature offspring of prenatal Poly l:C exposed rats.This study suggests that microglia activation may play a possible or potential role in the pathogenesis of schizophrenia.展开更多
Dear Editor,I am coauthor of the paper entitled 'Balance control of a humanoid robot based on the reaction null space method' by Akinori Nishio,Kentaro Takahashi and Dragomir N.Nenchev,published on pages
Two problems of a one-dimensional(1D)piezoelectric quasicrystal(QC)wedge are investigated,i.e.,the two sides of the wedge subject to uniform tractions and the wedge apex subject to the concentrated force.By virtue of ...Two problems of a one-dimensional(1D)piezoelectric quasicrystal(QC)wedge are investigated,i.e.,the two sides of the wedge subject to uniform tractions and the wedge apex subject to the concentrated force.By virtue of the Stroh formalism and Barnett-Lothe matrices,the analytical expressions of the displacements and stresses are derived,and the generalized solutions for the critical wedge angles are discussed.Numerical examples are given to present the mechanical behaviors of the wedge in each field.The results indicate that the effects of the uniform tractions and the concentrated force on the phonon field displacement are larger than those on the phason field.展开更多
The unusual properties of quasicrystals(QCs)have attracted tremendous attention from researchers.In this paper,a semi-analytical solution is presented for the static response of a functionally graded(FG)multilayered t...The unusual properties of quasicrystals(QCs)have attracted tremendous attention from researchers.In this paper,a semi-analytical solution is presented for the static response of a functionally graded(FG)multilayered two-dimensional(2 D)decagonal QC rectangular plate with mixed boundary conditions.Based on the elastic theory of FG 2 D QCs,the state-space method is used to derive the state equations composed of partial differential along the thickness direction.Besides,the Fourier series expansion and the differential quadrature technique are utilized to simulate the simply supported boundary conditions and the mixed boundary conditions,respectively.Then,the propagator matrix which connects the field variables at the upper interface to those at the lower interface of any homogeneous layer can be derived based on the state equations.Combined with the interface continuity condition,the static response can be obtained by imposing the sinusoidal load on the top surfaces of laminates.Finally,the numerical examples are presented to verify the effectiveness of this method,and the results are very useful for the design and understanding of the characterization of FG QC materials in their applications to multilayered systems.展开更多
A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method...A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method. The called "step strategy" can be modeled by means of the reaction null space method that introduced earlier to tackle dynamic interaction problems of free-floating robots, or moving base robots in general. 6-DOF biped robot model simulations are used to confirm the validity.展开更多
Background: The proximal femur is the most common site of bone metastasis, and metastasis at this site can cause chronic, intolerable pain and even result in pathologic fractures, thereby negatively affecting patients...Background: The proximal femur is the most common site of bone metastasis, and metastasis at this site can cause chronic, intolerable pain and even result in pathologic fractures, thereby negatively affecting patients’ quality of life. Selecting an appropriate method for resecting metastasis within the proximal femur requires thorough consideration of various factors, including the biological behavior of the primary tumor, the extent of the femur lesion, the current general systemic condition of the patient, and perioperative risks. Objective: To compare the perioperative safety of and early functional recovery following percutaneous femoroplasty (PFP) and proximal femoral replacement (PFR) in treating patients with metastasis of the proximal femur. Methods: We retrospectively analyzed the cases of 53 patients with proximal femur metastases who received surgical treatment by either PFP (n = 28) or PFR (n = 25). Perioperative blood loss, surgical time, and perioperative complications were compared between groups. Pain intensity according to the visual analogue scale (VAS) and early postoperative function according to the Karnofsky Performance Scale (KPS) were evaluated at 3, 7, and 30 days as well as 6 months after surgical treatment. Results: In the PFP group, the VAS scores were lower soon after operation than preoperation (P 0.05). PFP significantly and immediately improved patients’ quality of life as measured by the KPS in the early period after surgery (preoperative vs 3 days postoperative, P < 0.01), but the patients who underwent PFR suffered a short-term decrease in quality of life (preoperative vs 3 days postoperative, P < 0.01). Blood loss (P < 0.01) and operating time (P < 0.01) were significantly less than PFP. The complication rate was higher in the PFR group (28%) than in the PFP group (3.6%). The results also showed no difference in survival time between the two groups. Conclusion: PFP is an attractive minimally invasive therapeutic option for proximal femur metastasis that can significantly improve the patient’s quality of life in the short term.展开更多
Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA ...Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA separated from natto using microbial transglutaminase(MTG)as the crosslinker.The effects of the MTG mass concentration,gelation time,crosslinking temperature,pH,and the mass ratio of y-PGA to casein on the crosslinking ratio of y-PGA and swelling ratio of theγ-PGA/casein hydrogel were investigated.Furthermore,the synthesis conditions were optimized by response surface methodology to optimize three important factors,i.e.crosslinking temperature,pH and the mass ratio of y-PGA to casein.The results of single factor experiments showed that the MTG mass concentration and crosslinking time had little impacts on the crosslinking ratio of y-PGA and the swelling ratio;the preferred MTG mass concentration,crosslinking time,temperature and pH were selected as 0.3%,7 h,40℃and 7.5;and the preferred mass ratio ofγ-PGA to casein was 0.1 for the crosslinking ratio ofγ-PGA and 0.2 for the swelling ratio.The response surface experiment results showed that the optimum crosslinking temperature,pH and the mass ratio of y-PGA to casein ratio were 42.4℃,7.33,and 0.18,respectively.Under these optimum conditions,the predicted crosslinking ratio of y-PGA and swelling ratio reached 90.35%and 112.07%,which were highly consistent with the experimental values(88.00%and 115.87%).Theγ-PGA/casein composite hydrogel developed in this study shows promising application potential in food industry,biomedical field,and cosmetic industry.展开更多
Decades have passed since the first nanoparticles-base medicine was approved for human cancer treatment, and the research and development of nanoparticles for drug delivery are always undergoing.Nowadays, the signific...Decades have passed since the first nanoparticles-base medicine was approved for human cancer treatment, and the research and development of nanoparticles for drug delivery are always undergoing.Nowadays, the significant advances complicate nanoparticles’ branches, including liposomes, solid lipid nanoparticles, inorganic nanoparticles, micelles, nanovaccines and nano-antibodies, etc. These nanoparticles show numerous capabilities in treatment and diagnosis of stubborn diseases like cancer and neurodegenerative diseases, emerging as novel drug carriers or therapeutic agents in future. In this review, the complicated branches of nanoparticles are classified and summarized, with their property and functions concluded. Besides, there are also some delivery strategies that make nanoparticles smarter and more efficient in drug delivery, and frontiers in these strategies are also summarized in this review. Except these excellent works in newly-produced drug delivery nanoparticles, some points of view and future expectations are made in the end.展开更多
Water splitting by photoelectrochemical(PEC)processes to convert solar energy into hydrogen energy using semiconductors is regarded as one of the most ideal methods to solve the current energy crisis and has attracted...Water splitting by photoelectrochemical(PEC)processes to convert solar energy into hydrogen energy using semiconductors is regarded as one of the most ideal methods to solve the current energy crisis and has attracted widespread attention.Herein,Co-based metal-organic framework(Co(bpdc)(H_(2)O)_(4)(CoMOF)nanosheets as passivation layers were in-situ constructed on the surface of Bi VO_(4)films through an uncomplicated hydrothermal method(Co-MOF/Bi VO_(4)).Under AM 1.5G illumination,synthesized CoMOF/BiVO_(4)electrode exhibited a 4-fold higher photocurrent than bare Bi VO_(4),measuring 6.0 m A/cm^(2)at 1.23 V vs.RHE in 1 mol/L potassium borate electrolyte(pH 9.5)solution.Moreover,the Co-MOF/BiVO_(4)film demonstrated a 96%charge separation efficiency,a result caused by an inhibited recombination rate of photogenerated electrons and holes by the addition of Co-MOF nanosheets.This work provides an idea for depositing inexpensive 2D Co-MOF nanosheets on the photoanode as an excellent passivation layer for solar fuel production.展开更多
Herein,we proposed and demonstrated a facile and scalable strategy to fabricate multifunctional self-similar superhydrophobic coatings.Firstly,a hydrophobic cationic cellulose derivative containing imidazolium cation ...Herein,we proposed and demonstrated a facile and scalable strategy to fabricate multifunctional self-similar superhydrophobic coatings.Firstly,a hydrophobic cationic cellulose derivative containing imidazolium cation was synthesized by a controllable derivatization.It could effectively disperse one-dimensional(1D)multi-walled carbon nanotubes(MWCNT),because the imidazolium cations formed cation–πinteractions with MWCNT.Further,the synergy effect of the cationic cellulose derivative and MWCNT dispersed two-dimensional(2D)reduced graphene oxide(rGO)to obtain a three-components nano-dispersion.Finally,via a simple spaying process,a superhydrophobic coating with self-similar micro-nano structures spontaneously formed from inside to outside,owing to the various nanostructures with different shapes and sizes in the dispersion and the adhesive effect of the cellulose derivative.This superhydrophobic coating was easy to scale,exhibited superior stability owing to the renewal micro-nano structures.It retained the superhydrophobicity even if it was treated by rubbing for 1500 times.Moreover,it had outstanding photo-thermal and Joule-heating performance,because of the strong solar absorption and high electrical conductivity of MWCNT and rGO.It provided both passive anti-icing and active deicing effects.Thus,it could achieve all-weather anti-icing for wind power generators under sunlight and low voltage conditions.Such facile preparation method and multifunctional renewable superhydrophobic coating hold great application prospects.展开更多
Constructingeco-friendlystimuli-responsivephosphorescence materials remains challenging and fascinating.Herein,we use natural cellulose as the rawmaterial to prepare pH-responsive room-temperature phosphorescent(RTP)m...Constructingeco-friendlystimuli-responsivephosphorescence materials remains challenging and fascinating.Herein,we use natural cellulose as the rawmaterial to prepare pH-responsive room-temperature phosphorescent(RTP)materials with excellent biodegradability by introducing anionic structures.The introduction of a phenylcarboxylate substituent not only promotes intersystem crossing but also brings about electrostatic-attractive and strong hydrogenbonding interactions,which enhance the intermolecular chain interactions.Therefore,the obtained anionic cellulose derivatives containing phenylcarboxylate groups exhibit ultra-long RTP.More intriguingly,these cellulose-based phosphorescent materials have a distinctive pH-responsive behavior.Under acidic conditions,the carboxylate is converted into the carboxylic acid,resulting in phosphorescence quenching.This process is reversible.Moreover,the obtained cellulosebased phosphorescent materials have excellent processability and can be easily processed into various material forms,such as film,coating,and pattern,by using eco-friendly aqueous solution processing strategies.Such proof-of-concept biomass-based phosphorescent materials with unique pH-responsive behavior and excellent processability have a huge potential in information encryption,advanced anti-counterfeiting,and food monitoring.展开更多
How to achieve multicolor organic room-temperature phosphorescence(RTP)is still challenging and striking.Herein,we discovered a new principle to construct eco-friendly color-tunable RTP nanomaterials based on the nano...How to achieve multicolor organic room-temperature phosphorescence(RTP)is still challenging and striking.Herein,we discovered a new principle to construct eco-friendly color-tunable RTP nanomaterials based on the nano-surface confining effect.Cellulose nanocrystal(CNC)immobilized cellulose derivatives(CX)containing aromatic substituents via hydrogen-bonding interactions,which effectively inhibit the motion of cellulose chains and luminescent groups to suppress the nonradiative transitions.Meanwhile,CNC with a strong hydrogen-bonding network can isolate oxygen.CX with different aromatic substituents regulate the phosphorescent emission.After mixing CNC and CX directly,a series of polychromatic ultralong RTP nanomaterials were obtained.The RTP emission of the resultant CX@CNC can be finely adjusted through the introduction of various CX and the regulation of the CX/CNC ratio.Such a universal,facile,and effective strategy can be used to fabricate various colorful RTP materials with wide color gamut.Because of the complete biodegradability of cellulose,the multicolor phosphorescent CX@CNC nanomaterials can be used as eco-friendly security inks to fabricate disposable anticounterfeiting labels and information-storage patterns via conventional printing and writing processes.展开更多
The clinical application of triptolide(TPL)in tumor therapy has been greatly limited by its toxicity and inefficient delivery.Herein,a localized and sustained-release thermo-sensitive hydrogel was developed for the in...The clinical application of triptolide(TPL)in tumor therapy has been greatly limited by its toxicity and inefficient delivery.Herein,a localized and sustained-release thermo-sensitive hydrogel was developed for the intra-tumor administration of TPL.Based on the amphiphilic structure of poly(N-isopropylacrylamide-co-acrylic acid)-g-F68 copolymer,it was able to form nano-micelles to efficiently encapsulate TPL,and then turn into a hydrogel at 37C.TPL@nano-gel exhibited a sustained drug release profile in vitro and a stronger anticancer effect caused by"two strikes".The"first strike"was its enhanced cytotoxicity compared to free TPL,due to the enhanced pro-apoptosis effect observed in both MDA-MB-231 and MCF-7 cells caused by the regulation of endogenous mitochondrial pathways.Furthermore,TPL@nano-gel exhibited a"second-strike"through its anti-angiogenesis capabilities mediated through VEGFR-2 signaling inhibition.As expected,after intra-tumoral injection at a 0.45 mg/kg TPL-equivalent dose three times over 14 days in 4 T1 tumor-bearing mice,TPL@nano-gel led to lower systemic toxicity and higher antitumor efficacy compared to multiple injections of TPL.In this regard,these findings indicate that this injectable thermo-responsive hydrogel carries great potential for TPL as a safe and effective cancer therapy.展开更多
Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the r...Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica.Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid(9:1,v/v)as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black.Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode.Limit of detection(LOD)and limit of quantitation(LOQ)values were in the ranges 0.5-50 ng/g and 1-100 ng/g,respectively.The recoveries of the 39 pesticides were in the range 75-112% with precision(as relative standard deviation,RSD)<15%.The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.展开更多
基金supported by the National Natural Science Foundation of China(No.52173292)the National Key Research and Development Project of China(No.2020YFC1910303)the Youth Innovation Promotion Association CAS(No.2018040).
文摘Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.
基金the National Natural Science Foundation of China(Nos.11972365 and 12102458)。
文摘In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general solutions of displacements and stresses.Then,we obtain the analytical solutions of half-space and bimaterial Green’s functions.Besides,the interfacial Green’s function for bimaterials is also obtained in the analytical form.Before numerical studies,a comparative study is carried out to validate the present solutions.Typical numerical examples are performed to investigate the effects of multi-physics loadings such as the line force,the line dislocation,the line charge,and the phason line force.As a result,the coupling effect among the phonon field,the phason field,and the electric field is prominent,and the butterfly-shaped contours are characteristic in 2D PQCs.In addition,the changes of material parameters cause variations in physical quantities to a certain degree.
基金supported by National Natural Science Foundation of China (No.81973662)Distinguished Young Scholar of Sichuan Provincial Science and Technology Department (No.2019JDJQ0049)111 Project (No.B18035)
文摘The combination of Ce6,an acknowledged photosensitizer,and TPL,a natural anticancer agent,has been demonstrated as a useful strategy to reinforce the tumor growth suppression,as well as decrease the systemic side effects compared with their monotherapy.However,in view of the optimal chemo-photodynamic combination efficiency,there is still short of the feasible nanovehicle to steadily co-deliver Ce6 and TPL,and stimuli-responsively burst release drugs in tumor site.Herein,we described the synergistic antitumor performance of a pH-sensitive supramolecular nanosystem,mediated by the host–guest complexing betweenβ-CD and acid pH-responsive amphiphilic co-polymer mPEG-PBAE-mPEG,showing the shell–core structural micelles with the tightβ-CD layer coating.Both Ce6 and TPLwere facilely co-loaded into the spherical supramolecular NPs(TPL+Ce6/NPs)by one-step nanoprecipitation method,with an ideal particle size(156.0 nm),acid pH-responsive drug release profile,and enhanced cellular internalization capacity.In view of the combination benefit of photodynamic therapy and chemotherapy,as well as co-encapsulation in the fabricated pH-sensitive supramolecular NPs,TPL+Ce6/NPs exhibited significant efficacy to suppress cellular proliferation,boost ROS level,lower MMP,and promote cellular apoptosis in vitro.Particularly,fluorescence imaging revealed that TPL+Ce6/NPs preferentially accumulated in the tumor tissue area,with higher intensity than that of free Ce6.As expected,upon 650-nm laser irradiation,TPL+Ce6/NPs exhibited a cascade of amplified synergistic chemo-photodynamic therapeutic benefits to suppress tumor progression in both hepatoma H22 tumor-bearingmice and B16 tumor-bearingmice.More importantly,lower systemic toxicitywas found in the tumor-bearingmice treated with TPL+Ce6/NPs.Overall,the designed supramolecular TPL+Ce6/NPs provided a promising alternative approach for chemo-photodynamic therapy in tumor treatment.
基金provided by the National Natural Science Foundation of China(No 81571318 to XQSNo 81371472 to LXL+5 种基金No 81401110 to XL)the Science and Technology Planning Project of Health and Family Planning Commission(No 201501015 to XQS)the International Science and Technology Cooperation Program of Henan(No 162102410061 to XQS)the Henan Province Union Fund Project(162300410275)the Zhengzhou University doctor team projectthe Youth Fund of the First Affiliated Hospital of Zhengzhou University(to XL and LJP)
文摘Background The well-known <pyrotherapy, of Julius Wagner-Jauregg might be the beginning of the study on the immunological concepts of schizophrenia. As the primary immune effector cells in the brain, microglia play a pivotal role in neuroinflammatory processes. Maternal viral infection during pregnancy is associated with an increased risk for psychiatric disorders with presumed neurodevelopmental origin, including autism spectrum disorders and schizophrenia. The present study was to quantify microglia activation in vivo in the mature offspring of rats exposed to polyriboinosinic-polyribocytidilicacid(Poly l:C) during pregnancy using 11 C'PK11195 positron emission tomography(PET) and immunohistochemistry.Objective The study aimed to quantify microglia activation in vivo in the prefrontal cortex and hippocampus in mature offspring of prenatal Poly l:C exposed rats.Methods Offspring of Poly l:C-treated dams were the model group, offspring of saline-treated dams were the control group. Behavioural test for two groups was taken by spontaneous activity, prepulse inhibition(PPI) and latent inhibition(LI) test(including active avoidance conditioning task and passive avoidance conditioning task). Randomly selected successful model rats were assessed by behavioural test in the model group and control group rats.11 C-PK11195 micro-PET/CT and immunohistochemistry were performed on the selected rats to measure microglia activation.Results The treatment group showed hyperlocomotion and deficits in PPI and LI compared with the control group. The treatment group also showed an increased11 C-PK11195 uptake ratio in the prefrontal cortex(f=-3.990, p=0.003) and hippocampus(f=-4.462,p=0.001). The number of activated microglia cells was significantly higher in the treatment group than in the control gro叩(hippocampus: f=8.204, p<0.001; prefrontal:f=6.995, p<0.001). Within the treatment group, there were significant correlations between the behavioural parameters and the activation of microglia as measured by PET and immunohistochemistry.Conclusions The present study demonstrated microglia activation in vivo in the prefrontal cortex and hippocampus in mature offspring of prenatal Poly l:C exposed rats.This study suggests that microglia activation may play a possible or potential role in the pathogenesis of schizophrenia.
文摘Dear Editor,I am coauthor of the paper entitled 'Balance control of a humanoid robot based on the reaction null space method' by Akinori Nishio,Kentaro Takahashi and Dragomir N.Nenchev,published on pages
基金Project supported by the National Natural Science Foundation of China(Nos.11972365,12102458,11972354)the China Agricultural University Education Foundation(No.1101-2412001)。
文摘Two problems of a one-dimensional(1D)piezoelectric quasicrystal(QC)wedge are investigated,i.e.,the two sides of the wedge subject to uniform tractions and the wedge apex subject to the concentrated force.By virtue of the Stroh formalism and Barnett-Lothe matrices,the analytical expressions of the displacements and stresses are derived,and the generalized solutions for the critical wedge angles are discussed.Numerical examples are given to present the mechanical behaviors of the wedge in each field.The results indicate that the effects of the uniform tractions and the concentrated force on the phonon field displacement are larger than those on the phason field.
基金Project supported by the National Natural Science Foundation of China(Nos.11972354,11972365,12102458)the China Agricultural University Education Foundation(No.1101-2412001)。
文摘The unusual properties of quasicrystals(QCs)have attracted tremendous attention from researchers.In this paper,a semi-analytical solution is presented for the static response of a functionally graded(FG)multilayered two-dimensional(2 D)decagonal QC rectangular plate with mixed boundary conditions.Based on the elastic theory of FG 2 D QCs,the state-space method is used to derive the state equations composed of partial differential along the thickness direction.Besides,the Fourier series expansion and the differential quadrature technique are utilized to simulate the simply supported boundary conditions and the mixed boundary conditions,respectively.Then,the propagator matrix which connects the field variables at the upper interface to those at the lower interface of any homogeneous layer can be derived based on the state equations.Combined with the interface continuity condition,the static response can be obtained by imposing the sinusoidal load on the top surfaces of laminates.Finally,the numerical examples are presented to verify the effectiveness of this method,and the results are very useful for the design and understanding of the characterization of FG QC materials in their applications to multilayered systems.
基金supported by the National Natural Science Foundation of China (No.50675016)the Science and Technology Innovation Fund for the Doctor (No.48030)
文摘A biped walking robot should be able to keep balance even in the presence of disturbing forces. This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method. The called "step strategy" can be modeled by means of the reaction null space method that introduced earlier to tackle dynamic interaction problems of free-floating robots, or moving base robots in general. 6-DOF biped robot model simulations are used to confirm the validity.
文摘Background: The proximal femur is the most common site of bone metastasis, and metastasis at this site can cause chronic, intolerable pain and even result in pathologic fractures, thereby negatively affecting patients’ quality of life. Selecting an appropriate method for resecting metastasis within the proximal femur requires thorough consideration of various factors, including the biological behavior of the primary tumor, the extent of the femur lesion, the current general systemic condition of the patient, and perioperative risks. Objective: To compare the perioperative safety of and early functional recovery following percutaneous femoroplasty (PFP) and proximal femoral replacement (PFR) in treating patients with metastasis of the proximal femur. Methods: We retrospectively analyzed the cases of 53 patients with proximal femur metastases who received surgical treatment by either PFP (n = 28) or PFR (n = 25). Perioperative blood loss, surgical time, and perioperative complications were compared between groups. Pain intensity according to the visual analogue scale (VAS) and early postoperative function according to the Karnofsky Performance Scale (KPS) were evaluated at 3, 7, and 30 days as well as 6 months after surgical treatment. Results: In the PFP group, the VAS scores were lower soon after operation than preoperation (P 0.05). PFP significantly and immediately improved patients’ quality of life as measured by the KPS in the early period after surgery (preoperative vs 3 days postoperative, P < 0.01), but the patients who underwent PFR suffered a short-term decrease in quality of life (preoperative vs 3 days postoperative, P < 0.01). Blood loss (P < 0.01) and operating time (P < 0.01) were significantly less than PFP. The complication rate was higher in the PFR group (28%) than in the PFP group (3.6%). The results also showed no difference in survival time between the two groups. Conclusion: PFP is an attractive minimally invasive therapeutic option for proximal femur metastasis that can significantly improve the patient’s quality of life in the short term.
基金supported by the Doctoral Scientific Research Start-up Foundation from Henan University of Technology(No:2018BS072)。
文摘Theγ-PGA-based food hydrogel exhibits good biodegradability and biocompatibility,and is non-toxic to humans.In this study,a novel hydrogel(γ-PGA/casein composite hydrogel)was prepared by combining casein with y-PGA separated from natto using microbial transglutaminase(MTG)as the crosslinker.The effects of the MTG mass concentration,gelation time,crosslinking temperature,pH,and the mass ratio of y-PGA to casein on the crosslinking ratio of y-PGA and swelling ratio of theγ-PGA/casein hydrogel were investigated.Furthermore,the synthesis conditions were optimized by response surface methodology to optimize three important factors,i.e.crosslinking temperature,pH and the mass ratio of y-PGA to casein.The results of single factor experiments showed that the MTG mass concentration and crosslinking time had little impacts on the crosslinking ratio of y-PGA and the swelling ratio;the preferred MTG mass concentration,crosslinking time,temperature and pH were selected as 0.3%,7 h,40℃and 7.5;and the preferred mass ratio ofγ-PGA to casein was 0.1 for the crosslinking ratio ofγ-PGA and 0.2 for the swelling ratio.The response surface experiment results showed that the optimum crosslinking temperature,pH and the mass ratio of y-PGA to casein ratio were 42.4℃,7.33,and 0.18,respectively.Under these optimum conditions,the predicted crosslinking ratio of y-PGA and swelling ratio reached 90.35%and 112.07%,which were highly consistent with the experimental values(88.00%and 115.87%).Theγ-PGA/casein composite hydrogel developed in this study shows promising application potential in food industry,biomedical field,and cosmetic industry.
基金supported by National Natural Science Foundation of China (No. 81961138009)111 Project (No. B18035)the Key Research and Development Program of Science and Technology Department of Sichuan Province (No. 2020YFS0570)。
文摘Decades have passed since the first nanoparticles-base medicine was approved for human cancer treatment, and the research and development of nanoparticles for drug delivery are always undergoing.Nowadays, the significant advances complicate nanoparticles’ branches, including liposomes, solid lipid nanoparticles, inorganic nanoparticles, micelles, nanovaccines and nano-antibodies, etc. These nanoparticles show numerous capabilities in treatment and diagnosis of stubborn diseases like cancer and neurodegenerative diseases, emerging as novel drug carriers or therapeutic agents in future. In this review, the complicated branches of nanoparticles are classified and summarized, with their property and functions concluded. Besides, there are also some delivery strategies that make nanoparticles smarter and more efficient in drug delivery, and frontiers in these strategies are also summarized in this review. Except these excellent works in newly-produced drug delivery nanoparticles, some points of view and future expectations are made in the end.
基金financially supported by the National Natural Science Foundation of China(No.52173277)the Innovative Research Team for Science and Technology of Shaanxi Province(No.2022TD-04)+1 种基金the Fundamental Research Funds for the Central Universities of Chang’an University(Nos.300102299304,300102291403)the Natural Science Basic Research Fund of Shaanxi Province(No.2020JZ-20)。
文摘Water splitting by photoelectrochemical(PEC)processes to convert solar energy into hydrogen energy using semiconductors is regarded as one of the most ideal methods to solve the current energy crisis and has attracted widespread attention.Herein,Co-based metal-organic framework(Co(bpdc)(H_(2)O)_(4)(CoMOF)nanosheets as passivation layers were in-situ constructed on the surface of Bi VO_(4)films through an uncomplicated hydrothermal method(Co-MOF/Bi VO_(4)).Under AM 1.5G illumination,synthesized CoMOF/BiVO_(4)electrode exhibited a 4-fold higher photocurrent than bare Bi VO_(4),measuring 6.0 m A/cm^(2)at 1.23 V vs.RHE in 1 mol/L potassium borate electrolyte(pH 9.5)solution.Moreover,the Co-MOF/BiVO_(4)film demonstrated a 96%charge separation efficiency,a result caused by an inhibited recombination rate of photogenerated electrons and holes by the addition of Co-MOF nanosheets.This work provides an idea for depositing inexpensive 2D Co-MOF nanosheets on the photoanode as an excellent passivation layer for solar fuel production.
基金the National Natural Science Foundation of China(Nos.52173292,22122206,and U2004211)the Youth Innovation Promotion Association CAS(No.2018040).
文摘Herein,we proposed and demonstrated a facile and scalable strategy to fabricate multifunctional self-similar superhydrophobic coatings.Firstly,a hydrophobic cationic cellulose derivative containing imidazolium cation was synthesized by a controllable derivatization.It could effectively disperse one-dimensional(1D)multi-walled carbon nanotubes(MWCNT),because the imidazolium cations formed cation–πinteractions with MWCNT.Further,the synergy effect of the cationic cellulose derivative and MWCNT dispersed two-dimensional(2D)reduced graphene oxide(rGO)to obtain a three-components nano-dispersion.Finally,via a simple spaying process,a superhydrophobic coating with self-similar micro-nano structures spontaneously formed from inside to outside,owing to the various nanostructures with different shapes and sizes in the dispersion and the adhesive effect of the cellulose derivative.This superhydrophobic coating was easy to scale,exhibited superior stability owing to the renewal micro-nano structures.It retained the superhydrophobicity even if it was treated by rubbing for 1500 times.Moreover,it had outstanding photo-thermal and Joule-heating performance,because of the strong solar absorption and high electrical conductivity of MWCNT and rGO.It provided both passive anti-icing and active deicing effects.Thus,it could achieve all-weather anti-icing for wind power generators under sunlight and low voltage conditions.Such facile preparation method and multifunctional renewable superhydrophobic coating hold great application prospects.
基金supported by the Youth Innovation Promotion Association CAS(grant no.2018040)(J.M.Z.)the National Natural Science Foundation of China(grant nos.52173292 and U2004211)(J.M.Z.and J.Z.)the National Key Research and Development Project(grant no.2020YFC1910303)(J.Z.).
文摘Constructingeco-friendlystimuli-responsivephosphorescence materials remains challenging and fascinating.Herein,we use natural cellulose as the rawmaterial to prepare pH-responsive room-temperature phosphorescent(RTP)materials with excellent biodegradability by introducing anionic structures.The introduction of a phenylcarboxylate substituent not only promotes intersystem crossing but also brings about electrostatic-attractive and strong hydrogenbonding interactions,which enhance the intermolecular chain interactions.Therefore,the obtained anionic cellulose derivatives containing phenylcarboxylate groups exhibit ultra-long RTP.More intriguingly,these cellulose-based phosphorescent materials have a distinctive pH-responsive behavior.Under acidic conditions,the carboxylate is converted into the carboxylic acid,resulting in phosphorescence quenching.This process is reversible.Moreover,the obtained cellulosebased phosphorescent materials have excellent processability and can be easily processed into various material forms,such as film,coating,and pattern,by using eco-friendly aqueous solution processing strategies.Such proof-of-concept biomass-based phosphorescent materials with unique pH-responsive behavior and excellent processability have a huge potential in information encryption,advanced anti-counterfeiting,and food monitoring.
基金the National Natural Science Foundation of China(No.52173292 and U2004211)the Youth Innovation Promotion Association CAS(2018040)the National Key Research and Development Project(No.2020YFC1910303).
文摘How to achieve multicolor organic room-temperature phosphorescence(RTP)is still challenging and striking.Herein,we discovered a new principle to construct eco-friendly color-tunable RTP nanomaterials based on the nano-surface confining effect.Cellulose nanocrystal(CNC)immobilized cellulose derivatives(CX)containing aromatic substituents via hydrogen-bonding interactions,which effectively inhibit the motion of cellulose chains and luminescent groups to suppress the nonradiative transitions.Meanwhile,CNC with a strong hydrogen-bonding network can isolate oxygen.CX with different aromatic substituents regulate the phosphorescent emission.After mixing CNC and CX directly,a series of polychromatic ultralong RTP nanomaterials were obtained.The RTP emission of the resultant CX@CNC can be finely adjusted through the introduction of various CX and the regulation of the CX/CNC ratio.Such a universal,facile,and effective strategy can be used to fabricate various colorful RTP materials with wide color gamut.Because of the complete biodegradability of cellulose,the multicolor phosphorescent CX@CNC nanomaterials can be used as eco-friendly security inks to fabricate disposable anticounterfeiting labels and information-storage patterns via conventional printing and writing processes.
基金the financial support from the National Natural Science Foundation of China(Grant Nos.81973662and 8170371)Scientific Development Program of Sichuan Province(2019JDJQ0049,China)+1 种基金China Postdoctoral Science Foundation(Grant Nos.2017M612930 and 2019T120817)Young Elite Scientists Sponsorship Program by CAST(2018QNRC1-01,China)
文摘The clinical application of triptolide(TPL)in tumor therapy has been greatly limited by its toxicity and inefficient delivery.Herein,a localized and sustained-release thermo-sensitive hydrogel was developed for the intra-tumor administration of TPL.Based on the amphiphilic structure of poly(N-isopropylacrylamide-co-acrylic acid)-g-F68 copolymer,it was able to form nano-micelles to efficiently encapsulate TPL,and then turn into a hydrogel at 37C.TPL@nano-gel exhibited a sustained drug release profile in vitro and a stronger anticancer effect caused by"two strikes".The"first strike"was its enhanced cytotoxicity compared to free TPL,due to the enhanced pro-apoptosis effect observed in both MDA-MB-231 and MCF-7 cells caused by the regulation of endogenous mitochondrial pathways.Furthermore,TPL@nano-gel exhibited a"second-strike"through its anti-angiogenesis capabilities mediated through VEGFR-2 signaling inhibition.As expected,after intra-tumoral injection at a 0.45 mg/kg TPL-equivalent dose three times over 14 days in 4 T1 tumor-bearing mice,TPL@nano-gel led to lower systemic toxicity and higher antitumor efficacy compared to multiple injections of TPL.In this regard,these findings indicate that this injectable thermo-responsive hydrogel carries great potential for TPL as a safe and effective cancer therapy.
基金This work was supported by a project grant(No.09ZZ008)from the Scientific Research Fund of Sichuan Provincial Education Department,China.
文摘Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica.Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid(9:1,v/v)as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black.Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode.Limit of detection(LOD)and limit of quantitation(LOQ)values were in the ranges 0.5-50 ng/g and 1-100 ng/g,respectively.The recoveries of the 39 pesticides were in the range 75-112% with precision(as relative standard deviation,RSD)<15%.The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.