Up to date,solid-state carbon dots(CDs)with bright red fluorescence have scarcely achieved due to aggregation-caused quenching(ACQ)effect and extremely low quantum yield in deep-red to near infrared region.Here,we rep...Up to date,solid-state carbon dots(CDs)with bright red fluorescence have scarcely achieved due to aggregation-caused quenching(ACQ)effect and extremely low quantum yield in deep-red to near infrared region.Here,we report a novel fluorine-defects induced solid-state red fluorescence(λ_(em)=676 nm,the absolute fluorescence quantum yields is 4.17%)in fluorine,nitrogen and sulfur co-doped CDs(F,N,S-CDs),which is the first report of such a long wavelength emission of solid-state CDs.As a control,CDs without fluorine-doping(N,S-CDs)show no fluorescence in solid-state,and the fluorescence quantum yield/emission wavelength of N,S-CDs in solution-state are also lower/shorter than that of F,N,S-CDs,which is mainly due to the F-induced defect traps on the surface/edge of F,N,S-CDs.Moreover,the solid-state F,N,S-CDs exhibit an interesting temperature-sensitive behavior in the range of 80-420 K,with the maximum fluorescence intensity at 120 K,unveiling its potential as the temperature-dependent fluorescent sensor and the solid-state light-emitting device adapted to multiple temperatures.展开更多
The heat sensitivity of Human gingival squamous carcinoma Ca9-22 cells with oncogene erbB-1/EGFR and Chinese hamster V79 cells of normal thermosensitivity as control was investigated.Colony forming ability of the trea...The heat sensitivity of Human gingival squamous carcinoma Ca9-22 cells with oncogene erbB-1/EGFR and Chinese hamster V79 cells of normal thermosensitivity as control was investigated.Colony forming ability of the treated cells was assayed in vitro. Heat-treatment period-survival and the concerned curves were drawn.The slopes of exponentially regressing parts of the survival curves were estimated in the TO values of cellular thermosensitivity and subjected to Arrhenius analysis-The 42-44℃ time-survival curves of Ca9-22 cells showed biphasic slopes which indicated the presence of thermotolerance induction during continuous heating even at 44℃ while for the V79 cells the biphasic slopes due to thermotolerance induction were shown in temperatures at and before 42℃. In comparison of TO values with V79 cells, those of Ca9-22 cells were longer (less thermosensitive) by about 2.1 fold at 43℃ and 1-2 fold at 44℃. Both V79 and Ca9-22 cells were sensitized by 44--42℃ step-down heating (SDH).42℃ beat treatment period-survival curves of 44℃ ( 5minute) preheated V79 cells; while Ca9-22 cells under the same treatment condition for not only 5 minutes but 20 minutes showed biphasic slope, which indicated the Presence of thermotolerance. The thermosensitization ratio (TSR) of Ca9-22 cells were smaller than V79 cells.Arrhenius curves a breaking points at 44℃ and 43℃ for Ca9-22 and V79 cells, respectively. The activation energies of V79 cells were 145kcallmole and 400kcal/mole above and below 43℃ (p < 0.05), respectively,while those of Ca9-22 cells were 200 kcal/mole and 250kcal/mole above and below 44℃ (P <0.05), respectively.These data suggested that oncogene erbB-1 /EGFRcontained in Ca9-22 cells may contribute to reducethermosensitivity and variety in term of G ̄1 phase as shown in fractionated Hydroxyurea treatment.展开更多
The lower critical solution temperature (LCST) behavior of poly(acrylamide-co-diacetone acrylamide) (poly(AM-co-DAM)) copolymer in aqueous solutions was studied. The results demonstrate the LCST linearly decre...The lower critical solution temperature (LCST) behavior of poly(acrylamide-co-diacetone acrylamide) (poly(AM-co-DAM)) copolymer in aqueous solutions was studied. The results demonstrate the LCST linearly decreases as the molar fraction of DAM (fDAM) increases. In the range of fDAM 〈 0.36, the transmittance increases as fDAM decreases because the more hydrophilic copolymer chains can form looser aggregates with a lower refractive index. The transmittance exhibits a minimum when fDAM is less than 0.28 as the chains form micelle-like structure with a size smaller than the wavelength. The LCST decreases with the initial polymer concentration, but it levels off when the polymer concentration is high enough. Moreover, no hysteresis can be observed in the change of transmittance during the heating-cooling process because no additional hydrogen bonds are formed in the collapsed state due to the steric hindrance of the large side groups in DAM units.展开更多
Novel complex hydrogels of methylcellulose (MC) and poly(vinyl alcohol) (PVA) with wide-spectrum thermoresponsivity were prepared via physical and mild process. Thermal phase transition of MC/PVA hydrogels exhib...Novel complex hydrogels of methylcellulose (MC) and poly(vinyl alcohol) (PVA) with wide-spectrum thermoresponsivity were prepared via physical and mild process. Thermal phase transition of MC/PVA hydrogels exhibited two forms including sol/sol to gel/sol and sol/gel to gel/gel. The phase transition temperature of MC/PVA solution ranged from 38,7 to 60.6 ℃ and was able to be adjusted by simply changing the feeding ratios of two components. The interior morphology of MC/PVA gels was examined with fluorescence analysis and scanning electron microscopy analysis, which showed that MC was well dispersed in matrix before and after thermally gelling.展开更多
Controlled polymerization of N-n-propylacrylamide was achieved by atom transfer radical polymerization(ATRP) in a N,N-dimethylformamide-water mixture(50 vol%)at room temperature with methyl 2-chloropropinonate as init...Controlled polymerization of N-n-propylacrylamide was achieved by atom transfer radical polymerization(ATRP) in a N,N-dimethylformamide-water mixture(50 vol%)at room temperature with methyl 2-chloropropinonate as initiator and CuCl/tris(2-dimethylaminoethyl)amine as the catalytic system in a ratio of 1:1:1.High molecular weight homopolymers(up to 3.7×10~4)with narrow molecular weight distribution(less than 1.2)were obtained.The living character of the polymerization was further demonstrated by self-blocking...展开更多
The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this stu...The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this study,a thermal-deformative polymer embedding ultrasmall ceria(CeO_(2))was rationally designed for deep tumor drug shuttling and hypoxia reversal to improve chemotherapy.Structurally,the CeO_(2)nanozyme was covalently grafted with a polymer of p(NIPAM-co-AM)that could sharply shrink for DOX loading,which was consolidated with polydopamine(PDA)film encapsulation.Thereafter,a tumor penetration guide of apolipoprotein A-I(apoA-I)conjugated iRGD peptide(apoA-I-iRGD)was further decorated onto the PDA shell via Michael addition for preparing CeO_(2)P/DOX@iAPDA.With the aid of apoA-I-iRGD,CeO_(2)P/DOX@iAPDA penetrated both the tumor spheroids(∼78μm)and the tumors of the mouse model deeply.After internalization by tumor cells and triggering by low pH in lysosomes,rapid DOX release was achieved by peeling off the PDA shell and thermosensitive deformation of p(NIPAM-co-AM).CeO_(2)P/DOX@iAPDA provided 66.4%tumor suppression in 4T1-derived tumor spheroids and 63.2%in 4T1-tumorbearing mice,respectively.Preliminary mechanistic research involving western blotting and immunohistochemistry revealed that CeO_(2)P/DOX@iAPDA reversed resistance through the through HIF-1α-P-gp/lipid axis.Collectively,this study intelligently integrated CeO_(2)nanozymes,temperature-sensitive polymers,and imitated biochemical modifications to improve chemotherapy for breast cancer.展开更多
Parkinson's disease(PD)is a debilitating and progressive neurodegenerative disorder with complex pathology and multiple membrane barriers that hinder drug delivery,resulting in the absence of ideal therapeutic dru...Parkinson's disease(PD)is a debilitating and progressive neurodegenerative disorder with complex pathology and multiple membrane barriers that hinder drug delivery,resulting in the absence of ideal therapeutic drugs with minimal side effects[1].Recently,natural medicine has garnered significant attention due to its remarkable efficacy and limited side effects.Icariin,a naturally occurring flavonoid,exhibits excellent potential as a therapeutic agent for neurodegenerative disease[2].However,its clinical application is limited by poor water solubility,low bioavailability,and high clearance rates.Here,an aqueous formulation of icariin/hydroxypropyl-β-cyclodextrin(HP-β-CD)supramolecular inclusion complex was obtained to optimize icariin properties.Furthermore,icariin cyclodextrin supramolecular inclusion complex based thermosensitive(icariin gels)was innovated.At lower temperatures,it remained in a liquid phase with high fluidity.Upon reaching the gelation temperature,it underwent a transition to a gel phase with significantly reduced fluidity,which may be suitable for the design of an intranasal delivery system for PD treatment.The innovative approach capitalizes on the exceptional characteristics of HP-β-CD,which was utilized to synergize with nasal delivery for targeted brain delivery and with icariin for PD treatment[3,4].展开更多
Carbon dots(CDs)with superior fluorescence properties have attracted a growing number of research interests in anti-counterfeiting.However,the preparation of CDs with thermally turn-on fluorescence and full-color-emit...Carbon dots(CDs)with superior fluorescence properties have attracted a growing number of research interests in anti-counterfeiting.However,the preparation of CDs with thermally turn-on fluorescence and full-color-emitting in visible spectrum is still a big challenge due to the complicated reaction mechanism in the formation of CDs.Here,a simple precursor-oriented strategy for the preparation of multicolor CDs with heat-stimuli turn-on fluorescence is reported.Comprehensive experimental characterizations and theoretical calculations revealed that the emission wavelength of CDs can be readily tuned from 460 nm to 654 nm with selected precursors,which was ascribed to the extent of conjugated sp2-domains(core states)and the amount of oxygen-and nitrogen-containing groups bound to sp2-domains(surface states).After simply mixing two or three kinds of CDs,a full-color range of fluorescence emission was realized,and the CDs-based fluorescence inks were successfully fabricated.Particularly,all the printed patterns from the inkjet exhibited a thermal-induced enhancement in fluorescence.On this basis,combining CDs with heating-induced“turn-off”fluorescence materials can lead to multidimensional and multistage encryption.These results demonstrate that the thermochromic and photochromic CDs with much more enhanced security exhibit promising application in data storage and encryption.展开更多
The main goal of the article is the creation and study of thermosensitive and wound-healing gelatin-alginate bio-polymer hydrogels modified with humic acids.Their rheological properties,swelling and contraction behavi...The main goal of the article is the creation and study of thermosensitive and wound-healing gelatin-alginate bio-polymer hydrogels modified with humic acids.Their rheological properties,swelling and contraction behavior were experimentally investigated,elucidated using Fourier transform infrared spectroscopy and used to achieve the physiological melting point,which is necessary for successful drug delivery.It has been shown that in the gelatin-alginate-humic acid biopolymer hydrogels systems,it is possible to obtain a gel-sol transition temperature close to the physiological temperature of 37℃,which is important for drug delivery in the treatment of wounds.By changing the type and concentration of humic acids in the gelatin-alginate hydrogel,it turned out to be achiev-able to regulate the softening time of the gel on the human body in the range from 6 to 20 min,which provides the possibility of controlled prolonged delivery of drugs.Based on the study of the influence of calcium ions on the properties of humic acids and ion exchange,as well as the interaction of humic acids,sodium alginate and gelatin with the formation of tighter gel networks,approaches to regulate the rate of softening of hydrogels at physiological temperature and their swelling,which simulates the absorption of exudate,were proposed and implemented.In addition,low shrinkage of the hydrogel surface due to cross-linking of gelatin-alginate networks when modified with humic acids was experimentally confirmed,which is important for avoiding problems of wound contracture and contour deformations when using dressings for wound healing.Thus,the developed opti-mized innovative biopolymer hydrogels synergistically combine the outstanding properties of natural molecular polymers and humic acids and are promising for the creation of effective medicines for wound healing.展开更多
Precision therapy has become the preferred choice attributed to the optimal drug concentration in target sites,increased therapeutic efficacy,and reduced adverse effects.Over the past few years,sprayable or injectable...Precision therapy has become the preferred choice attributed to the optimal drug concentration in target sites,increased therapeutic efficacy,and reduced adverse effects.Over the past few years,sprayable or injectable thermosensitive hydrogels have exhibited high therapeutic potential.These can be applied as cell-growing scaffolds or drug-releasing reservoirs by simply mixing in a free-flowing sol phase at room temperature.Inspired by their unique properties,thermosensitive hydrogels have been widely applied as drug delivery and treatment platforms for precision medicine.In this review,the state-of-theart developments in thermosensitive hydrogels for precision therapy are investigated,which covers from the thermo-gelling mechanisms and main components to biomedical applications,including wound healing,anti-tumor activity,osteogenesis,and periodontal,sinonasal and ophthalmic diseases.The most promising applications and trends of thermosensitive hydrogels for precision therapy are also discussed in light of their unique features.展开更多
Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic ker...Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.展开更多
Polyelectrolyte solutions are more variable than uncharged macromolecule due to electrical interaction between charged molecules and surrounding counterions.Therefore,the subject of polyelectrolyte solutions has attra...Polyelectrolyte solutions are more variable than uncharged macromolecule due to electrical interaction between charged molecules and surrounding counterions.Therefore,the subject of polyelectrolyte solutions has attracted a wide range of interests in both basic and applied research,and has also been extensively explored.However,the understanding of the molecular dynamics and conformation of polyelectrolytes in solution remains to be deepened,and universal consensus on some key issues have not been reached.Many methods have contributed to solving the above problems in different ways,including dielectric relaxation spectroscopy(DRS).In this perspective,we briefly reviewed the history of dielectric spectroscopic research on polyelectrolyte solution,with emphasis on summarizing our efforts.In particular,we expound the characteristics of DRS and its ability to obtain the internal information of the system of interest.Finally,we evaluate the advantages and limitations of the dielectric method and discussed future prospects of this field.展开更多
Bladder cancer is a common malignant tumor of the urinary system with the potential to be treated by nano drug delivery system.The current work describes the synthesis and characterization of a novel nanomaterial to c...Bladder cancer is a common malignant tumor of the urinary system with the potential to be treated by nano drug delivery system.The current work describes the synthesis and characterization of a novel nanomaterial to construct a nano-carrier based on 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatecholine(POPC)loaded doxorubicin(DOX)and embedded with gold nanoparticles and poly(N-isopropyl acry-lamide)(PNIPAM)(GNPS@PNIPAM-POPC-DOX,GPPD).The dual-sensitive nanosystem gives simultaneous photothermal treatment and chemotherapy for bladder cancer.In vitro and in vivo properties were as-sessed using bladder cancer cell lines and mice and GPPD system distribution,tumor inhibition,and biocompatibility are reported.The system had favorable stability,low biological toxicity,controlled re-lease efficiency,photothermal synergistic action,efficient photothermal transition,and favorable tumor suppressive effects.As a result,GPPD is a potential therapeutic approach for bladder cancer.展开更多
Amultifunctional liposomal polydopamine nanoparticle(MPM@Lipo)was designed in this study,to combine chemotherapy,photothermal therapy(PTT)and oxygen enrichment to clear hyperproliferating inflammatory cells and improv...Amultifunctional liposomal polydopamine nanoparticle(MPM@Lipo)was designed in this study,to combine chemotherapy,photothermal therapy(PTT)and oxygen enrichment to clear hyperproliferating inflammatory cells and improve the hypoxic microenvironment for rheumatoid arthritis(RA)treatment.MPM@Lipo significantly scavenged intracellular reactive oxygen species and relieved joint hypoxia,thus contributing to the repolarization of M1 macrophages into M2 phenotype.Furthermore,MPM@Lipo could accumulate at inflammatory joints,inhibit the production of inflammatory factors,and protect cartilage in vivo,effectively alleviating RA progression in a rat adjuvant-induced arthritis model.Moreover,upon laser irradiation,MPM@Lipo can elevate the temperature to not only significantly obliterate excessively proliferating inflammatory cells but also accelerate the production of methotrexate and oxygen,resulting in excellent RA treatment effects.Overall,the use of synergistic chemotherapy/PTT/oxygen enrichment therapy to treat RA is a powerful potential strategy.展开更多
Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylami...Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylamide)(PNIPAM)single chain and cross-linking thermosensitive hydrogel through molecular dynamics simulation.Specifically,the impact of lower critical solution temperature(LCST)on the conformation of polymer chain and the interaction between water and polymer chain were also investigated.The polymer chain conformation underwent a transition from coil to globule when the temperature exceeded the LCST,indicating the temperature responsiveness of PNIPAM.Additionally,thermosensitive hydrogel samples with different cross-linking degrees(DOC)were studied,and relevant parameters such as the number of free water,the diffusion coefficient of water,and the pore size distribution were counted to evaluate the temperature responsiveness and water release characteristics of thermosensitive hydrogel.展开更多
In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkag...In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkage map of rice. Total of 142 newly screened AFLP markers and 30 anchor markers (25 SSR markers and 5 RFLP markers) were mapped on the 12 chromosomes covering 1537.4 cM of rice genome. The average interval between these markers was 9.0 cM. The total work which usually was finished in more than one year was finished within only 3 months by one person. This is the first plant AFLP map developed in China. A new thermosensitive genic male sterile gene in rice, tms5, was Egged and mapped onto chromosome 2 during the development of the linkage map.展开更多
Aim To develop pluronic F127 (PF127) based formulations of penciclovir (PCV) aimed at enhancing its ocular bioavailability. Methods Thermosensitive in situ gels of penciclovir were prepared through combination of ...Aim To develop pluronic F127 (PF127) based formulations of penciclovir (PCV) aimed at enhancing its ocular bioavailability. Methods Thermosensitive in situ gels of penciclovir were prepared through combination of HPMC K4M or carbopol 934P and pluronic F127. Optimized formulations were examined through measuring gelation temperature, rheology speciality, drug release behavior, pharmacokinetics and ocular irritation. Results The gelation temperature was reduced by adding HPMC K4M or carbopol 934P, and the viscosity was enhanced slightly. Either HPMC K4M or carbopol 934P delayed the release of PCV from in situ gel. PCV was released by non-Fickian diffusion. The study of ocular irritation for different PCV formulations did not show any irritation or damage for the cornea. PCV bioavailability from combination of carbopol 934P and pluronic F127 gels was higher than that obtained from any other gels. Conclusion Pluronic F127 formulations of PCV can be used as liquid for administration by instilling into the eye. Facilitated by the appropriate eye temperature, the formulations were transformed to gel phase. On the basis of in vitro and in vivo results, PCV formulations containing HPMC K4M or carbopol 934P and low concentration of pluronic F127 (12%) showed potential for use as a drug delivery system with improved ocular bioavailability.展开更多
Adenine phosphoribosyltransferase (APRT) is the major enzyme that converts adenine into adenosine-3'-phosphate (AMP). APRT-deficient mutant caused by APRT gene mutation results in the male sterility in Arabidopsis...Adenine phosphoribosyltransferase (APRT) is the major enzyme that converts adenine into adenosine-3'-phosphate (AMP). APRT-deficient mutant caused by APRT gene mutation results in the male sterility in Arabidopsis thaliana L. In order to confirm the existence of rice APRT gene and to investigate its association with thermo-sensitive genic male sterile (TGMS) phenotype of rice, a APRT gene was identified from BLAST search of the rice genome database using APRT gene sequences from other plant species as probes. Further, the gene was cloned from rice and named APRT(GenBank accession number AY238894) using the combination of bioinformatic and experimental approaches. The rice APRT was located in the 56 000 bp to 63 000 bp region of a rice bacterial artificial chromosome (BAC) clone (AL606604) on chromosome 4 and was deduced by software from the positive DNA clone. Its cDNA was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) using primers designed according to the sequence of the putative gene. The full-length cDNA was obtained by rapid amplification of cDNA ends (RACE) procedure and was sequenced. Open reading frame (ORF) analysis indicated that the rice APRT gene encodes a peptide of 212 amino acid residues, including seven exons and six introns. Using reverse position specific BLAST (RPS-BLAST), the APRT domain was identified in the polypeptide. The homology comparison demonstrated that the polypeptide exhibits 54.9%, 54.9%, 49.6% and 59.5% identity with that from Hordeum vulgare, Ttriticum aestivum, and A. thaliana (APRT types 1 and 2), respectively. Comparing the sequence of APRT gene from TGMS mutant lines 'Annong S-1' (Oryza sativa subsp. indica) with that from its corresponding wild type 'Annong F' (Oryza sativa. subsp. indica), we found that there are five single nucleotid polymorphism (SNP) sites in the gene of 'Annong S-1', which locate mainly in the second intron. However, the result of cDNA sequencing showed that these SNP sites do not damage the successful splicing of intron 2. Qualitative RT-PCR and Northern blot indicated that the gene tran-scription in the 'Annong S-1' young panicles that were verified to be the thermo-sensitive organ at the early stage of pollen fertility alternation is down-regulated by high temperature stress (28 V), which is the critical temperature causing 'Annong S-1' fertility conversion. These results revealed that the change of expression pattern of APRT in young particles of 'Annong S-1' in high temperature conditions is perhaps related to the TGMS of 'Annong S-1'.展开更多
Novel colloidal processing using thermosensitive poly(N-isopropylacrylamide) (PNIPAM) as a coagulating agent has beendeveloped to prepare complex-shaped ceramic components. In this work, the properties of PNIPAM a...Novel colloidal processing using thermosensitive poly(N-isopropylacrylamide) (PNIPAM) as a coagulating agent has beendeveloped to prepare complex-shaped ceramic components. In this work, the properties of PNIPAM aqueous solutions and therheological behavior of ZnO suspensions with PNIPAM were investigated. The results show that the PNIPAM solutions exhibitobvious thermosensitivity and its transition temperature is around 32℃. When the temperature is above 40℃ (Tc, the criticaltransition temperature of thermosensitive suspension), the 50% ZnO (volume fraction) suspension with 8 mg/mL PNIPAM has asharp increase in viscosity and reaches up to 11.49 Pa·s at 50℃, displaying strong elasticity. The main reasons are the increase ofeffective volume fraction attributed to precipitation of PNIPAM segments and the flocculation between ZnO powder particles. Inaddition, the maximum solid loading (volume fraction) at 20 ℃ is higher than that at 40℃, which proves that the phase transition ofPNIPAM can induce the flocculation of suspension.展开更多
Global warming threatens food security.Rice(Oryza sativa L.),a vital food crop,is vulnerable to heat stress,especially at the reproductive stage.Here we summarize putative mechanisms of high-temperature perception(via...Global warming threatens food security.Rice(Oryza sativa L.),a vital food crop,is vulnerable to heat stress,especially at the reproductive stage.Here we summarize putative mechanisms of high-temperature perception(via RNA secondary structure,the phyB gene,and phase separation)and response(membrane fluidity,heat shock factors,heat shock proteins,and ROS(reactive oxygen species)scavenging)in plants.We describe how rice responds to heat stress at different cell-component levels(membrane,endoplasmic reticulum,chloroplasts,and mitochondria)and functional levels(denatured protein elimination,ROS scavenging,stabilization of DNA and RNA,translation,and metabolic flux changes).We list temperature-sensitive genetic male sterility loci available for use in rice hybrid breeding and explain the regulatory mechanisms associated with some of them.Breeding thermotolerant rice species without yield penalties via natural alleles mining and transgenic editing should be the focus of future work.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51772001)Anhui Province Key Research and Development Plan Project International Science and Technology Cooperation Special Project(No.202004bll020015)support of the Key Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University),Ministry of Education.
文摘Up to date,solid-state carbon dots(CDs)with bright red fluorescence have scarcely achieved due to aggregation-caused quenching(ACQ)effect and extremely low quantum yield in deep-red to near infrared region.Here,we report a novel fluorine-defects induced solid-state red fluorescence(λ_(em)=676 nm,the absolute fluorescence quantum yields is 4.17%)in fluorine,nitrogen and sulfur co-doped CDs(F,N,S-CDs),which is the first report of such a long wavelength emission of solid-state CDs.As a control,CDs without fluorine-doping(N,S-CDs)show no fluorescence in solid-state,and the fluorescence quantum yield/emission wavelength of N,S-CDs in solution-state are also lower/shorter than that of F,N,S-CDs,which is mainly due to the F-induced defect traps on the surface/edge of F,N,S-CDs.Moreover,the solid-state F,N,S-CDs exhibit an interesting temperature-sensitive behavior in the range of 80-420 K,with the maximum fluorescence intensity at 120 K,unveiling its potential as the temperature-dependent fluorescent sensor and the solid-state light-emitting device adapted to multiple temperatures.
文摘The heat sensitivity of Human gingival squamous carcinoma Ca9-22 cells with oncogene erbB-1/EGFR and Chinese hamster V79 cells of normal thermosensitivity as control was investigated.Colony forming ability of the treated cells was assayed in vitro. Heat-treatment period-survival and the concerned curves were drawn.The slopes of exponentially regressing parts of the survival curves were estimated in the TO values of cellular thermosensitivity and subjected to Arrhenius analysis-The 42-44℃ time-survival curves of Ca9-22 cells showed biphasic slopes which indicated the presence of thermotolerance induction during continuous heating even at 44℃ while for the V79 cells the biphasic slopes due to thermotolerance induction were shown in temperatures at and before 42℃. In comparison of TO values with V79 cells, those of Ca9-22 cells were longer (less thermosensitive) by about 2.1 fold at 43℃ and 1-2 fold at 44℃. Both V79 and Ca9-22 cells were sensitized by 44--42℃ step-down heating (SDH).42℃ beat treatment period-survival curves of 44℃ ( 5minute) preheated V79 cells; while Ca9-22 cells under the same treatment condition for not only 5 minutes but 20 minutes showed biphasic slope, which indicated the Presence of thermotolerance. The thermosensitization ratio (TSR) of Ca9-22 cells were smaller than V79 cells.Arrhenius curves a breaking points at 44℃ and 43℃ for Ca9-22 and V79 cells, respectively. The activation energies of V79 cells were 145kcallmole and 400kcal/mole above and below 43℃ (p < 0.05), respectively,while those of Ca9-22 cells were 200 kcal/mole and 250kcal/mole above and below 44℃ (P <0.05), respectively.These data suggested that oncogene erbB-1 /EGFRcontained in Ca9-22 cells may contribute to reducethermosensitivity and variety in term of G ̄1 phase as shown in fractionated Hydroxyurea treatment.
基金financially supported by the Ministry of Science and Technology of China(No.2012CB933802)the National Natural Science Foundation of China(Nos.21004057 and 21004058)
文摘The lower critical solution temperature (LCST) behavior of poly(acrylamide-co-diacetone acrylamide) (poly(AM-co-DAM)) copolymer in aqueous solutions was studied. The results demonstrate the LCST linearly decreases as the molar fraction of DAM (fDAM) increases. In the range of fDAM 〈 0.36, the transmittance increases as fDAM decreases because the more hydrophilic copolymer chains can form looser aggregates with a lower refractive index. The transmittance exhibits a minimum when fDAM is less than 0.28 as the chains form micelle-like structure with a size smaller than the wavelength. The LCST decreases with the initial polymer concentration, but it levels off when the polymer concentration is high enough. Moreover, no hysteresis can be observed in the change of transmittance during the heating-cooling process because no additional hydrogen bonds are formed in the collapsed state due to the steric hindrance of the large side groups in DAM units.
基金the support by Natural Science Foundation of Fujian Province of China(No.E0640005)for this project.
文摘Novel complex hydrogels of methylcellulose (MC) and poly(vinyl alcohol) (PVA) with wide-spectrum thermoresponsivity were prepared via physical and mild process. Thermal phase transition of MC/PVA hydrogels exhibited two forms including sol/sol to gel/sol and sol/gel to gel/gel. The phase transition temperature of MC/PVA solution ranged from 38,7 to 60.6 ℃ and was able to be adjusted by simply changing the feeding ratios of two components. The interior morphology of MC/PVA gels was examined with fluorescence analysis and scanning electron microscopy analysis, which showed that MC was well dispersed in matrix before and after thermally gelling.
基金This work was supported by the National Natural Science Foundation of China through Young Investigator Award(No.20328407)Nankai University,and the Canada Research Chair program.
文摘Controlled polymerization of N-n-propylacrylamide was achieved by atom transfer radical polymerization(ATRP) in a N,N-dimethylformamide-water mixture(50 vol%)at room temperature with methyl 2-chloropropinonate as initiator and CuCl/tris(2-dimethylaminoethyl)amine as the catalytic system in a ratio of 1:1:1.High molecular weight homopolymers(up to 3.7×10~4)with narrow molecular weight distribution(less than 1.2)were obtained.The living character of the polymerization was further demonstrated by self-blocking...
基金supported by National Natural Science Foundation of China(Nos.82473949 and 82273955)Scientific research project of Jiangsu Provincial Health Commission(No.M2022080)+1 种基金Jiangsu Province Capability Improvement Project through Science,Technology and Education(ZDXK202234)Jiangsu Provincial Research Hospital(YJXYY202204),China.
文摘The effective intracellular accumulation of doxorubicin(DOX)is crucial for improving antitumor efficacy,which is severely impeded by limited drug penetration,uncontrollable drug release,and drug resistance.In this study,a thermal-deformative polymer embedding ultrasmall ceria(CeO_(2))was rationally designed for deep tumor drug shuttling and hypoxia reversal to improve chemotherapy.Structurally,the CeO_(2)nanozyme was covalently grafted with a polymer of p(NIPAM-co-AM)that could sharply shrink for DOX loading,which was consolidated with polydopamine(PDA)film encapsulation.Thereafter,a tumor penetration guide of apolipoprotein A-I(apoA-I)conjugated iRGD peptide(apoA-I-iRGD)was further decorated onto the PDA shell via Michael addition for preparing CeO_(2)P/DOX@iAPDA.With the aid of apoA-I-iRGD,CeO_(2)P/DOX@iAPDA penetrated both the tumor spheroids(∼78μm)and the tumors of the mouse model deeply.After internalization by tumor cells and triggering by low pH in lysosomes,rapid DOX release was achieved by peeling off the PDA shell and thermosensitive deformation of p(NIPAM-co-AM).CeO_(2)P/DOX@iAPDA provided 66.4%tumor suppression in 4T1-derived tumor spheroids and 63.2%in 4T1-tumorbearing mice,respectively.Preliminary mechanistic research involving western blotting and immunohistochemistry revealed that CeO_(2)P/DOX@iAPDA reversed resistance through the through HIF-1α-P-gp/lipid axis.Collectively,this study intelligently integrated CeO_(2)nanozymes,temperature-sensitive polymers,and imitated biochemical modifications to improve chemotherapy for breast cancer.
基金supported by the National Natural Science Foundation of China(Grant No.:82104399)the Science and Technology Project of Haihe Laboratory of Modern Chinese Medicine,China(Grant No.:22HHZYSS00001).
文摘Parkinson's disease(PD)is a debilitating and progressive neurodegenerative disorder with complex pathology and multiple membrane barriers that hinder drug delivery,resulting in the absence of ideal therapeutic drugs with minimal side effects[1].Recently,natural medicine has garnered significant attention due to its remarkable efficacy and limited side effects.Icariin,a naturally occurring flavonoid,exhibits excellent potential as a therapeutic agent for neurodegenerative disease[2].However,its clinical application is limited by poor water solubility,low bioavailability,and high clearance rates.Here,an aqueous formulation of icariin/hydroxypropyl-β-cyclodextrin(HP-β-CD)supramolecular inclusion complex was obtained to optimize icariin properties.Furthermore,icariin cyclodextrin supramolecular inclusion complex based thermosensitive(icariin gels)was innovated.At lower temperatures,it remained in a liquid phase with high fluidity.Upon reaching the gelation temperature,it underwent a transition to a gel phase with significantly reduced fluidity,which may be suitable for the design of an intranasal delivery system for PD treatment.The innovative approach capitalizes on the exceptional characteristics of HP-β-CD,which was utilized to synergize with nasal delivery for targeted brain delivery and with icariin for PD treatment[3,4].
基金the Natural National Science Foundation of China (No. 51973083)the Fundamental Research Funds for the Central Universities (No. JUSRP22027)clinical research and translational medicine program of affiliated hospital of Jiangnan University (No. LCYJ202239).
文摘Carbon dots(CDs)with superior fluorescence properties have attracted a growing number of research interests in anti-counterfeiting.However,the preparation of CDs with thermally turn-on fluorescence and full-color-emitting in visible spectrum is still a big challenge due to the complicated reaction mechanism in the formation of CDs.Here,a simple precursor-oriented strategy for the preparation of multicolor CDs with heat-stimuli turn-on fluorescence is reported.Comprehensive experimental characterizations and theoretical calculations revealed that the emission wavelength of CDs can be readily tuned from 460 nm to 654 nm with selected precursors,which was ascribed to the extent of conjugated sp2-domains(core states)and the amount of oxygen-and nitrogen-containing groups bound to sp2-domains(surface states).After simply mixing two or three kinds of CDs,a full-color range of fluorescence emission was realized,and the CDs-based fluorescence inks were successfully fabricated.Particularly,all the printed patterns from the inkjet exhibited a thermal-induced enhancement in fluorescence.On this basis,combining CDs with heating-induced“turn-off”fluorescence materials can lead to multidimensional and multistage encryption.These results demonstrate that the thermochromic and photochromic CDs with much more enhanced security exhibit promising application in data storage and encryption.
文摘The main goal of the article is the creation and study of thermosensitive and wound-healing gelatin-alginate bio-polymer hydrogels modified with humic acids.Their rheological properties,swelling and contraction behavior were experimentally investigated,elucidated using Fourier transform infrared spectroscopy and used to achieve the physiological melting point,which is necessary for successful drug delivery.It has been shown that in the gelatin-alginate-humic acid biopolymer hydrogels systems,it is possible to obtain a gel-sol transition temperature close to the physiological temperature of 37℃,which is important for drug delivery in the treatment of wounds.By changing the type and concentration of humic acids in the gelatin-alginate hydrogel,it turned out to be achiev-able to regulate the softening time of the gel on the human body in the range from 6 to 20 min,which provides the possibility of controlled prolonged delivery of drugs.Based on the study of the influence of calcium ions on the properties of humic acids and ion exchange,as well as the interaction of humic acids,sodium alginate and gelatin with the formation of tighter gel networks,approaches to regulate the rate of softening of hydrogels at physiological temperature and their swelling,which simulates the absorption of exudate,were proposed and implemented.In addition,low shrinkage of the hydrogel surface due to cross-linking of gelatin-alginate networks when modified with humic acids was experimentally confirmed,which is important for avoiding problems of wound contracture and contour deformations when using dressings for wound healing.Thus,the developed opti-mized innovative biopolymer hydrogels synergistically combine the outstanding properties of natural molecular polymers and humic acids and are promising for the creation of effective medicines for wound healing.
基金financially supported by the National Natural Science Foundation of China(Grants 52172276)fund from Anhui Provincial Institute of Translational Medicine(2021zhyx-B15)。
文摘Precision therapy has become the preferred choice attributed to the optimal drug concentration in target sites,increased therapeutic efficacy,and reduced adverse effects.Over the past few years,sprayable or injectable thermosensitive hydrogels have exhibited high therapeutic potential.These can be applied as cell-growing scaffolds or drug-releasing reservoirs by simply mixing in a free-flowing sol phase at room temperature.Inspired by their unique properties,thermosensitive hydrogels have been widely applied as drug delivery and treatment platforms for precision medicine.In this review,the state-of-theart developments in thermosensitive hydrogels for precision therapy are investigated,which covers from the thermo-gelling mechanisms and main components to biomedical applications,including wound healing,anti-tumor activity,osteogenesis,and periodontal,sinonasal and ophthalmic diseases.The most promising applications and trends of thermosensitive hydrogels for precision therapy are also discussed in light of their unique features.
基金supported by PLA General Hospital Program,No.LB20201A010024(to LW).
文摘Neurotrophic keratopathy is a persistent defect of the corneal epithelium,with or without stromal ulceration,due to corneal nerve deficiency caused by a variety of etiologies.The treatment options for neurotrophic keratopathy are limited.In this study,an ophthalmic solution was constructed from a chitosan-based thermosensitive hydrogel with long-term release of murine nerve growth factor(CTH-mNGF).Its effectiveness was evaluated in corneal denervation(CD)mice and patients with neurotrophic keratopathy.In the preclinical setting,CTH-mNGF was assessed in a murine corneal denervation model.CTH-mNGF was transparent,thermosensitive,and ensured sustained release of mNGF for over 20 hours on the ocular surface,maintaining the local mNGF concentration around 1300 pg/mL in vivo.Corneal denervation mice treated with CTH-mNGF for 10 days showed a significant increase in corneal nerve area and total corneal nerve length compared with non-treated and CTH treated mice.A subsequent clinical trial of CTH-mNGF was conducted in patients with stage 2 or 3 neurotrophic keratopathy.Patients received topical CTH-mNGF twice daily for 8 weeks.Fluorescein sodium images,Schirmer’s test,intraocular pressure,Cochet-Bonnet corneal perception test,and best corrected visual acuity were evaluated.In total,six patients(total of seven eyes)diagnosed with neurotrophic keratopathy were enrolled.After 8 weeks of CTH-mNGF treatment,all participants showed a decreased area of corneal epithelial defect,as stained by fluorescence.Overall,six out of seven eyes had fluorescence staining scores<5.Moreover,best corrected visual acuity,intraocular pressure,Schirmer’s test and Cochet-Bonnet corneal perception test results showed no significant improvement.An increase in corneal nerve density was observed by in vivo confocal microscopy after 8 weeks of CTH-mNGF treatment in three out of seven eyes.This study demonstrates that CTH-mNGF is transparent,thermosensitive,and has sustained-release properties.Its effectiveness in healing corneal epithelial defects in all eyes with neurotrophic keratopathy suggests CTH-mNGF has promising application prospects in the treatment of neurotrophic keratopathy,being convenient and cost effective.
基金supported by the National Natural Science Foundation of China(Nos.21673002,21473012 and 21173025).
文摘Polyelectrolyte solutions are more variable than uncharged macromolecule due to electrical interaction between charged molecules and surrounding counterions.Therefore,the subject of polyelectrolyte solutions has attracted a wide range of interests in both basic and applied research,and has also been extensively explored.However,the understanding of the molecular dynamics and conformation of polyelectrolytes in solution remains to be deepened,and universal consensus on some key issues have not been reached.Many methods have contributed to solving the above problems in different ways,including dielectric relaxation spectroscopy(DRS).In this perspective,we briefly reviewed the history of dielectric spectroscopic research on polyelectrolyte solution,with emphasis on summarizing our efforts.In particular,we expound the characteristics of DRS and its ability to obtain the internal information of the system of interest.Finally,we evaluate the advantages and limitations of the dielectric method and discussed future prospects of this field.
基金funded by the National Natural Science Foundation of China(Nos.92059112,82072821,31470964)the Shanghai Songjiang Municipal Science and Technology Commission Natural Science Foundation(No.20SJKJGG250)+1 种基金University of Shanghai for Science and Technology(No.10–21–302–405)sponsored by the Program of Shanghai Academic Research Leader(No.22XD1404700)
文摘Bladder cancer is a common malignant tumor of the urinary system with the potential to be treated by nano drug delivery system.The current work describes the synthesis and characterization of a novel nanomaterial to construct a nano-carrier based on 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatecholine(POPC)loaded doxorubicin(DOX)and embedded with gold nanoparticles and poly(N-isopropyl acry-lamide)(PNIPAM)(GNPS@PNIPAM-POPC-DOX,GPPD).The dual-sensitive nanosystem gives simultaneous photothermal treatment and chemotherapy for bladder cancer.In vitro and in vivo properties were as-sessed using bladder cancer cell lines and mice and GPPD system distribution,tumor inhibition,and biocompatibility are reported.The system had favorable stability,low biological toxicity,controlled re-lease efficiency,photothermal synergistic action,efficient photothermal transition,and favorable tumor suppressive effects.As a result,GPPD is a potential therapeutic approach for bladder cancer.
文摘Amultifunctional liposomal polydopamine nanoparticle(MPM@Lipo)was designed in this study,to combine chemotherapy,photothermal therapy(PTT)and oxygen enrichment to clear hyperproliferating inflammatory cells and improve the hypoxic microenvironment for rheumatoid arthritis(RA)treatment.MPM@Lipo significantly scavenged intracellular reactive oxygen species and relieved joint hypoxia,thus contributing to the repolarization of M1 macrophages into M2 phenotype.Furthermore,MPM@Lipo could accumulate at inflammatory joints,inhibit the production of inflammatory factors,and protect cartilage in vivo,effectively alleviating RA progression in a rat adjuvant-induced arthritis model.Moreover,upon laser irradiation,MPM@Lipo can elevate the temperature to not only significantly obliterate excessively proliferating inflammatory cells but also accelerate the production of methotrexate and oxygen,resulting in excellent RA treatment effects.Overall,the use of synergistic chemotherapy/PTT/oxygen enrichment therapy to treat RA is a powerful potential strategy.
基金supported by National Natural Science Foundation of China(No.52206073)Fundamental Research Funds for the Central Universities(No.3132023119)Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515011379 and 2023A1515110613).
文摘Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylamide)(PNIPAM)single chain and cross-linking thermosensitive hydrogel through molecular dynamics simulation.Specifically,the impact of lower critical solution temperature(LCST)on the conformation of polymer chain and the interaction between water and polymer chain were also investigated.The polymer chain conformation underwent a transition from coil to globule when the temperature exceeded the LCST,indicating the temperature responsiveness of PNIPAM.Additionally,thermosensitive hydrogel samples with different cross-linking degrees(DOC)were studied,and relevant parameters such as the number of free water,the diffusion coefficient of water,and the pore size distribution were counted to evaluate the temperature responsiveness and water release characteristics of thermosensitive hydrogel.
文摘In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkage map of rice. Total of 142 newly screened AFLP markers and 30 anchor markers (25 SSR markers and 5 RFLP markers) were mapped on the 12 chromosomes covering 1537.4 cM of rice genome. The average interval between these markers was 9.0 cM. The total work which usually was finished in more than one year was finished within only 3 months by one person. This is the first plant AFLP map developed in China. A new thermosensitive genic male sterile gene in rice, tms5, was Egged and mapped onto chromosome 2 during the development of the linkage map.
文摘Aim To develop pluronic F127 (PF127) based formulations of penciclovir (PCV) aimed at enhancing its ocular bioavailability. Methods Thermosensitive in situ gels of penciclovir were prepared through combination of HPMC K4M or carbopol 934P and pluronic F127. Optimized formulations were examined through measuring gelation temperature, rheology speciality, drug release behavior, pharmacokinetics and ocular irritation. Results The gelation temperature was reduced by adding HPMC K4M or carbopol 934P, and the viscosity was enhanced slightly. Either HPMC K4M or carbopol 934P delayed the release of PCV from in situ gel. PCV was released by non-Fickian diffusion. The study of ocular irritation for different PCV formulations did not show any irritation or damage for the cornea. PCV bioavailability from combination of carbopol 934P and pluronic F127 gels was higher than that obtained from any other gels. Conclusion Pluronic F127 formulations of PCV can be used as liquid for administration by instilling into the eye. Facilitated by the appropriate eye temperature, the formulations were transformed to gel phase. On the basis of in vitro and in vivo results, PCV formulations containing HPMC K4M or carbopol 934P and low concentration of pluronic F127 (12%) showed potential for use as a drug delivery system with improved ocular bioavailability.
文摘Adenine phosphoribosyltransferase (APRT) is the major enzyme that converts adenine into adenosine-3'-phosphate (AMP). APRT-deficient mutant caused by APRT gene mutation results in the male sterility in Arabidopsis thaliana L. In order to confirm the existence of rice APRT gene and to investigate its association with thermo-sensitive genic male sterile (TGMS) phenotype of rice, a APRT gene was identified from BLAST search of the rice genome database using APRT gene sequences from other plant species as probes. Further, the gene was cloned from rice and named APRT(GenBank accession number AY238894) using the combination of bioinformatic and experimental approaches. The rice APRT was located in the 56 000 bp to 63 000 bp region of a rice bacterial artificial chromosome (BAC) clone (AL606604) on chromosome 4 and was deduced by software from the positive DNA clone. Its cDNA was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) using primers designed according to the sequence of the putative gene. The full-length cDNA was obtained by rapid amplification of cDNA ends (RACE) procedure and was sequenced. Open reading frame (ORF) analysis indicated that the rice APRT gene encodes a peptide of 212 amino acid residues, including seven exons and six introns. Using reverse position specific BLAST (RPS-BLAST), the APRT domain was identified in the polypeptide. The homology comparison demonstrated that the polypeptide exhibits 54.9%, 54.9%, 49.6% and 59.5% identity with that from Hordeum vulgare, Ttriticum aestivum, and A. thaliana (APRT types 1 and 2), respectively. Comparing the sequence of APRT gene from TGMS mutant lines 'Annong S-1' (Oryza sativa subsp. indica) with that from its corresponding wild type 'Annong F' (Oryza sativa. subsp. indica), we found that there are five single nucleotid polymorphism (SNP) sites in the gene of 'Annong S-1', which locate mainly in the second intron. However, the result of cDNA sequencing showed that these SNP sites do not damage the successful splicing of intron 2. Qualitative RT-PCR and Northern blot indicated that the gene tran-scription in the 'Annong S-1' young panicles that were verified to be the thermo-sensitive organ at the early stage of pollen fertility alternation is down-regulated by high temperature stress (28 V), which is the critical temperature causing 'Annong S-1' fertility conversion. These results revealed that the change of expression pattern of APRT in young particles of 'Annong S-1' in high temperature conditions is perhaps related to the TGMS of 'Annong S-1'.
基金Project(51202296)supported by the National Natural Science Foundation of ChinaProject(20120162120006)supported by the Specialized Research Fund for the Doctoral Program of Higher Education,China
文摘Novel colloidal processing using thermosensitive poly(N-isopropylacrylamide) (PNIPAM) as a coagulating agent has beendeveloped to prepare complex-shaped ceramic components. In this work, the properties of PNIPAM aqueous solutions and therheological behavior of ZnO suspensions with PNIPAM were investigated. The results show that the PNIPAM solutions exhibitobvious thermosensitivity and its transition temperature is around 32℃. When the temperature is above 40℃ (Tc, the criticaltransition temperature of thermosensitive suspension), the 50% ZnO (volume fraction) suspension with 8 mg/mL PNIPAM has asharp increase in viscosity and reaches up to 11.49 Pa·s at 50℃, displaying strong elasticity. The main reasons are the increase ofeffective volume fraction attributed to precipitation of PNIPAM segments and the flocculation between ZnO powder particles. Inaddition, the maximum solid loading (volume fraction) at 20 ℃ is higher than that at 40℃, which proves that the phase transition ofPNIPAM can induce the flocculation of suspension.
基金supported by the National Natural Science Foundation of China(31630052,31788103)Chinese Academy of Sciences(XDB27010104,QYZDYSSW-SMC023,159231KYSB20200008)+1 种基金the National Key Research and Development Program of China(2016YFD0100604)the Shanghai Science and Technology Development(18JC1415000)。
文摘Global warming threatens food security.Rice(Oryza sativa L.),a vital food crop,is vulnerable to heat stress,especially at the reproductive stage.Here we summarize putative mechanisms of high-temperature perception(via RNA secondary structure,the phyB gene,and phase separation)and response(membrane fluidity,heat shock factors,heat shock proteins,and ROS(reactive oxygen species)scavenging)in plants.We describe how rice responds to heat stress at different cell-component levels(membrane,endoplasmic reticulum,chloroplasts,and mitochondria)and functional levels(denatured protein elimination,ROS scavenging,stabilization of DNA and RNA,translation,and metabolic flux changes).We list temperature-sensitive genetic male sterility loci available for use in rice hybrid breeding and explain the regulatory mechanisms associated with some of them.Breeding thermotolerant rice species without yield penalties via natural alleles mining and transgenic editing should be the focus of future work.