Hollow Ni Mo-based nitride heterojunction with super-hydrophilic/aerophobic surface for efficient urea-assisted hydrogen production

Hydrogen evolution reaction(HER)and urea oxidation reaction(UOR)are key reactions of the watercycling associated catalytic process/device.The design of catalysts with a super-hydrophilic/aerophobic structure and optimized electron distribution holds great promise.Here,we have designed a threedimensional(3D)hollow Ni/NiMoN hierarchical structure with arrayed-sheet surface based on a onepot hydrothermal route for efficient urea-assisted HER based on a simple hydrothermal process.The Ni/NiMoN catalyst exhibits super-hydrophilic/aerophobic properties with a small droplet contact angle of 6.07°and an underwater bubble contact angle of 155.7°,thus facilitating an escape of bubbles from the electrodes.Density functional theory calculations and X-ray photoelectron spectroscopy results indicate the optimized electronic structure at the interface of Ni and NiMoN,which can promote the adsorption/desorption of reactants and intermediates.The virtues combining with a large specific surface area endow Ni/NiMoN with efficient catalytic activity of low potentials of 25 mV for HER and 1.33 V for UOR at10 mA cm^(-2).The coupled HER and UOR system demonstrates a low cell voltage of 1.42 V at 10 mA cm^(-2),which is approximately 209 mV lower than water electrolysis.

Tissue optical clearing enhances efficacy of vascular targeted photodynamic therapy of mouse dorsal skin

Vascular-targeted photodynamic therapy(V-PDT)is an effective treatment for port wine stains(PWS).However,repeated treatment is usually needed to achieve optimal treatment outcomes,possibly due to the limited treatment light penetration depth in the PWS lesion.The optical clearing technique can increase light penetration in depth by reducing light scattering.This study aimed to investigate the V-PDT in combination with an optical clearing agent(OCA)for the therapeutic enhancement of V-PDT in the rodent skinfold window chamber model.Vascular responses were closely monitored with laser speckle contrast imaging(LSCI),optical coherence tomography angiography,and stereo microscope before,during,and after the treatment.We further quantitatively demonstrated the effects of V-PDT in combination with OCA on the blood flow and blood vessel size of skin microvasculature.The combination of OCA and V-PDT resulted in significant vascular damage,including vasoconstriction and the reduction of blood flow.Our results indicate the promising potential of OCA for enhancing V-PDT for treating vascular-related diseases,including PWS.

Anti-PD1 antibody and not anti-LAG-3 antibody improves the antitumor effect of photodynamic therapy for treating metastatic breast cancer

Photodynamic therapy(PDT)has limited effects in treating metastatic breast cancer.Immune checkpoints can deplete the function of immune cells;however,the expression of immune checkpoints after PDT is unclear.This study investigates whether the limited e±cacy of PDT is due to upregulated immune checkpoints and tries to combine the PDT and immune checkpoint inhibitor to observe the e±cacy.A metastatic breast cancer model was treated by PDT mediated by hematoporphyrin derivatives(HpD-PDT).The anti-tumor effect of HpD-PDT was observed,as well as CD4þT,CD8þT and calreticulin(CRT)by immunohistochemistry and immunofluorescence.Immune checkpoints on T cells were analyzed byflow cytometry after HpD-PDT.When combining PDT with immune checkpoint inhibitors,the antitumor effect and immune effect were assessed.For HpD-PDT at 100 mW/cm2 and 40,60 and 80 J/cm2,primary tumors were suppressed and CD4þT,CD8þT and CRT were elevated;however,distant tumors couldn't be inhibited and survival could not be prolonged.Immune checkpoints on T cells,especially PD1 and LAG-3 after HpD-PDT,were upregulated,which may explain the reason for the limited HpD-PDT effect.After PDT combined with anti-PD1 antibody,but not with anti-LAG-3 antibody,both the primary and distant tumors were signi-cantly inhibited and the survival time was prolonged,additionally,CD4þT,CD8þT,IFN-þCD4þT and TNF-þCD4þT cells were signi-cantly increased compared with HpD-PDT.HpD-PDT could not combat metastatic breast cancer.PD1 and LAG-3 were upregulated after HpD-PDT.Anti-PD1 antibody,but not anti-LAG-3 antibody,could augment the antitumor effect of HpD-PDT for treating metastatic breast cancer.

Lobe-dominatedγ-Ray Emission of Compact Symmetric Objects

Theγ-ray emitting compact symmetric objects(CSOs)PKS 1718-649,NGC 3894,and TXS 0128+554 are lobedominated in the radio emission.In order to investigate theirγ-ray radiation properties,we analyze the~14yr Fermi/LAT observation data of the three CSOs.They all show the low luminosity(1041-1043 erg s-1)and no significant variability in theγ-ray band.Theirγ-ray average spectra can be well fitted by a power-law function.These properties ofγ-rays are clearly different from theγ-ray emitting CSOs CTD 135 and PKS 1413+135,for which theγ-rays are produced by a restarted aligned jet.In the L_(γ)-Γ_(γ)plane,the three CSOs are also located at the region occupied by radio galaxies(RGs)while CTD 135 and PKS 1413+135 display a similar feature to blazars.Together with a similar radio emission property toγ-ray emitting RGs Cen A and Fornax A,we speculate that theγ-rays of the three CSOs stem from their extended mini-lobes.The broadband spectral energy distributions of the three CSOs can be well explained by the two-zone leptonic model,where theirγ-rays are produced by the inverse Compton process of the relativistic electrons in extended regions.By extrapolating the observed Fermi/LAT spectra to the very high energy band,we find that TXS 0128+554 among the three CSOs may be detected by the Cherenkov Telescope Array in the future.

深度学习在内镜下内痔诊断及危险分级中的应用

目的建立内镜下内痔诊断及危险分级的深度学习模型,探讨人工智能辅助内镜下内痔诊疗的可行性。方法收集该院内镜中心的肛齿状线上倒镜图片,分为内痔组和正常组(A任务);根据LDRf分级标准,将内痔组进一步分为Rf0组、Rf1组和Rf2组(B任务)。选取基于卷积神经网络(CNN)框架的Xception、ResNet和EfficientNet,以及基于Transformer框架的ViT和ConvMixer等5个神经网络,建立针对A、B两项计算机视觉任务的深度学习模型。模型评价指标包括准确率、召回率、精确度、F1值和读片时间。将深度学习模型的读片表现与两位不同年资内镜医生进行比较。结果5种深度学习模型在A与B任务测试集中皆展现出较好的准确性。其中,最优模型为ConvMixer,准确性最高(0.961和0.911),其次为EfficientNet(0.956和0.901),均优于高年资内镜医生(0.952和0.881)和低年资内镜医生(0.913和0.832)。同时,所有深度学习模型在验证集中读片用时均<10 s,速度快于内镜医生(均>300 s)。此外,笔者采用梯度加权分类激活映射(Grad-CAM)方法突出图像中对模型判断较重要的区域。结论建立的内痔诊断及危险分级的深度学习模型,其表现优于内镜医生。基于深度学习的计算机视觉模型可辅助内镜医师进行内痔诊断和分级,展现出潜在的临床应用前景。

TMEM16F may be a new therapeutic target for Alzheimer's disease

TMEM16F is involved in many physiological processes such as blood coagulation,cell membrane fusion and bone mineralization.Activation of TMEM16F has been studied in various central nervous system diseases.High TMEM16F level has been also found to participate in microglial phagocytosis and transformation.Microglia-mediated neuroinflammation is a key factor in promoting the progression of Alzheimer’s disease.However,few studies have examined the effects of TMEM16F on neuroinflammation in Alzheimer’s disease.In this study,we established TMEM16F-knockdown AD model in vitro and in vivo to investigate the underlying regulatory mechanism about TMEM16F-mediated neuroinflammation in AD.We performed a Morris water maze test to evaluate the spatial memory ability of animals and detected markers for the microglia M1/M2 phenotype and NLRP3 inflammasome.Our results showed that TMEM16F was elevated in 9-month-old APP/PS1 mice.After TMEM16F knockdown in mice,spatial memory ability was improved,microglia polarization to the M2 phenotype was promoted,NLRP3 inflammasome activation was inhibited,cell apoptosis and Aβplaque deposition in brain tissue were reduced,and brain injury was alleviated.We used amyloid-beta(Aβ_(25-35))to stimulate human microglia to construct microglia models of Alzheimer’s disease.The levels of TMEM16F,inducible nitric oxide synthase(iNOS),proinflammatory cytokines and NLRP3 inflammasome-associated biomarkers were higher in Aβ_(25-35) treated group compared with that in the control group.TMEM16F knockdown enhanced the expression of the M2 phenotype biomarkers Arg1 and Socs3,reduced the release of proinflammatory factors interleukin-1,interleukin-6 and tumor necrosis factor-α,and inhibited NLRP3 inflammasome activation through reducing downstream proinflammatory factors interleukin-1βand interleukin-18.This inhibitory effect of TMEM16F knockdown on M1 microglia was partially reversed by the NLRP3 agonist Nigericin.Our findings suggest that TMEM16F participates in neuroinflammation in Alzheimer’s disease through participating in polarization of microglia and activation of the NLRP3 inflammasome.These results indicate that TMEM16F inhibition may be a potential therapeutic approach for Alzheimer’s disease treatment.

Cu/碳纳米纤维负载脂肪酸定形相变材料的制备与性能

结合静电纺丝、物理吸附、预氧化炭化和原位还原的技术与原理,制备了3种不同铜纳米粒子含量的Cu/碳纳米纤维膜(Cu/CNFs1~3),从此作为定形相变材料(FSPCM)的支撑基体;根据最低共熔点理论和Schrader方程计算出月桂酸-肉豆蔻酸-硬脂酸(LA-MA-SA)三元脂肪酸的质量比例,用作制备FSPCM的相变物质。通过物理吸附法制备了Cu/CNFs负载LA-MA-SA的FSPCM1~3。探讨了不同铜纳米粒子含量的CNFs对FSPCM形貌与导热性能的影响。结果表明,FSPCM1~3的熔融时间分别缩短了23.0%、51.8%和38.2%,结晶时间分别缩短了47.8%、64.0%和62.6%。制备的FSPCM1~3的熔融相变温度和熔融热焓在32~36℃和88~122 kJ/kg之间,结晶相变温度和结晶热焓分别在24~26℃和89~120.9 kJ/kg之间。

Photodynamic therapy for high-grade dysplasia of bile duct via a choledochoscope

When a distal common bile duct neoplasm is at the stage of carcinoma in situ or high-grade dysplasia,it is difficult for the surgeon to decide whether to perform pancreaticoduodenectomy.Here we describe a patient with a progressive dysplastic lesion in the common bile duct,which developed from moderate-high to highgrade dysplasia in approximately 2 mo.The patient refused major surgery.Therefore,endoscopic-assisted photodynamic therapy was performed.The result at follow-up using a trans-T-tube choledochoscope showed that the lesion was completely necrotic.This report is the first to describe the successful treatment of highgrade dysplasia of the distal bile duct using photodynamic therapy via a choledochoscope.

Weichang'an and 5-fluorouracil suppresses colorectal cancer in a mouse model

AIM: To examine the effect of Weichang'an(WCA) and 5-fluorouracil(5-Fu) on colorectal tumor and hepatic metastasis in a mouse model. METHODS: Quantitative determination of hesperidin, the effective component in WCA decoction, was performed using Hp LC. In vitro cytotoxicity of WCA was determined by treating HCT-116 cells with WCA diluents or serum extracted from rats that received WCA by oral gavage for 1 wk and MTT assays. Forty-eight nude mice received cecum implantation with tumor blocks subcutaneously amplified from human colon cancer cell line HCT-116. Mice were randomly divided into four treatment groups: control(CON), WCA, 5-Fu and combination(WCA + 5-Fu). pathological examination of tumors consisted of tissue sectioning and hematoxylin and eosin staining. Tumor weight and size were measured, and the number of metastatic l e s i o n s wa s c o u n t e d. S e r u m c a r c i n o e m b r yo n i c antigen(CEA) level was determined by ELISA. The expression levels of tumor genesis and metastasisrelated proteins β-catenin and matrix metalloproteinase(MMp)-7 were measured by real-time quantitative reverse transcriptase polymerase chain reaction(RTp CR), immunohistochemistry and immunoblotting. Cell fractionation was used to investigate intracellular distribution of β-catenin.RESULTS: parenchymal tumors were palpable in the abdomens of nude mice 2 wk post-implantation and orthotopic tumor formation rate was 100% in all groups. 5-Fu treatment alone significantly decreased tumor weight compared to the CON group(1.203 ± 0.284 g vs 1.804 ± 0.649 g, p < 0.01). WCA treatment alone reduced the rate of metastasis(50% vs 100%,p < 0.05). Combination treatment of WCA + 5-Fu was the most effective, reducing the tumor weight(1.140 ± 0.464 g vs 1.804 ± 0.649 g, p < 0.01) and size(1493.438 ± 740.906 mm3 vs 2180.259 ± 816.556 mm3, p < 0.05), the rate of metastases(40% vs 100%, p < 0.01), and serum CEA levels(31.263 ± 7.421 μg/L vs 43.040 ± 11.273 μg/L, p < 0.05). Expression of β-catenin and MMp-7 was decreased in drug-treated groups compared to controls, as detected using realtime quantitative RT-p CR, immunohistochemistry and immunoblotting, respectively. Cell fractionation assays revealed that nuclear translocation of β-catenin was reduced by WCA and/or 5-Fu treatments. CONCLUSION: Combination of WCA with 5-Fu significantly inhibited colon tumor growth and hepatic metastases. Decreased expression of β-catenin and MMp-7 may be important.

Immune response induced by hematoporphyrin derivatives mediated photodynamic therapy:Immunogenic cell death and elevated costimulatory molecules

Photodynamic therapy(PDT)not only destroys tumor cells directly but also induced anti-tumor immune response through damage-associated molecular patterns(DAMPs).It is reported that anti-tumor response was associated with light dose and photosensitizer used in PDT.In this study,4T1 tumor cells were implanted on both the right and left flanks of mice.Only the right tumor was treated by HpD-PDT,while the left tumor was not irradiated.The anti-tumor immune response induced by HpD-PDT was investigated.The expression of DAMPs and costimulatory molecules induced by HpD-PDT were tested by immuno fluorescence and flow cytometry in vivo.Different light doses of PDT were designed to treat 4T1 cells.The killing effect was assessed by CCK-8 kit and apoptosis kit.The expression of DAMPs on 4T1 cells after HpDPDT were evaluated by flow cytometry,western blot and ATP kit.This study showed that CD4^(+)T,CD8^(+)T and the production of IFN-γwere increased significantly on day 10 in righttumor after PDT treatment compared with control group.HpD-PDT enhanced the expression of calreticulin(CRT)on tumor tissue.Importantly,co-stimulatory molecular OX-40 and 4-1BB were elevated on CD8^(+)T cells.In vitro,immunogenic death of 4T1 cells was induced after PDT.Besides,the expression of DAMPs increased with the increasing of energy density.This study indicates that anti-tumor immune effect was induced by HpD-PDT.The knowledge of the involvement of CRT,ATP and co-stimulatory molecules uncovers important mechanistic insight into the anti-tumor immunogenicity.It was the first time that co-stimulatory molecules were investigated and found to elevate after PDT.

Comparative study on Photobiomodulation between 630 nm and 810 nm LED in diabetic wound healing both in vitro and in vivo

Photobiomodulation(PBM)promoting wound healing has been demonstrated by many studies.Currently,630 nm and 810 nm light-emitting diodes(LEDs),as light sources,are frequently used in the treatment of diabetic foot ulcers(DFUs)in clinics.However,the dose-effect relationship of LED-mediated PBM is not fully understood.Furthermore,among the 630 nm and 810 nm LEDs,which one gets a better effect on accelerating the wound healing of diabetic ulcers is not clear.The aim of this study is to evaluate and compare the effects of 630 nm and 810 nm LED-mediated PBM in wound healing both in vitro and in vivo.Our results showed that both 630 nm and 810 nm LED irradiation significantly promoted the proliferation of mouse fibroblast cells(L929)at different light irradiances(1,5,and 10 mW/cm^(2)).The cell proliferation rate increased with the extension of irradiation time(100,200,and 500 s),but it decreased when the irradiation time was over 500 s.Both 630 nm and 810nm LED irradiation(5 mW/cm^(2))significantly improved the migration capability of L929 cells.No difference between 630 nm and 810 nm LED-mediated PBM in promoting cell proliferation and migration was detected.In vivo results presented that both 630 nm and 810 nm LED irradiation promoted the wound healing and the expression of the vascular endothelial growth factor(VEGF)and transforming growth factor(TGF)in the wounded skin of type 2 diabetic mice.Overall,these results suggested that LED-mediated PBM promotes wound healing of diabetic mice through promoting fibroblast cell proliferation,migration,and the expression of growth factors in the wounded skin.LEDs(630 nm and 810 nm)have a similar outcome in promoting wound healing of type 2 diabetic mice.

Improvement in Resolution of Multiphoton Scanning Structured Illumination Microscopy via Harmonics

We describe a multiphoton(mP)-structured illumination microscopy(SIM)technique,which demonstrates substantial improvement in image resolution compared with linear SIM due to the nonlinear response of fluorescence.This nonlinear response is caused by the effect of nonsinusoidal structured illumination created by scanning a sinusoidally modulated illumination to excite an mP fluorescence signal.The harmonics of the structured fluorescence illumination are utilised to improve resolution.We present an mP-SIM theory for reconstructing the super-resolution image of the system.Theoretically,the resolution of our m P-SIM is unlimited if all the high-order harmonics of the nonlinear response of fluorescence are considered.Experimentally,we demonstrate an 86 nm lateral resolution for two-photon(2P)-SIM and a 72 nm lateral resolution for second-harmonic-generation(SHG)-SIM.We further demonstrate their application by imaging cells stained with F-actin and collagen fibres in mouse-tail tendon.Our method can be directly used in commercial mP microscopes and requires no specific fluorophores or high-intensity laser.

SINGLET OXYGEN DETECTION DURING PHOTOSENSITIZATION

Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifcation of^(1)O_(2) generation during in vitro and in vivo pho-tosensitization is still technically challenging.To address this problem,indirect and direct methods for^(1)O_(2)detection have been intensively studied.This review presents the available methods currently in use or under development for detecting and quantifying^(1)O_(2) generation during photosensitization.The advantages and limitations of each method will be presented.Moreover,the future trends in developing PDT-^(1)O_(2) dosimetry will be briefly discussed.

AUTOMATED ASSESSMENT OF EPIDERMAL THICKNESS AND VASCULAR DENSITY OF PORT WINE STAINS OCT IMAGE

Optical coherence tomography(OCT)enables in vivo imaging of port wine stains(PWS)lesions.The knowledge of vascular struct ure and epidermal thickness(ET)of PWS may aid the objectivediagnosis and optimal treatment.To obtain the structural parameters more rapidly and avoiduser intervention,an automated algorithm of energy map is introduced based on intensity andedge information to extract the skin surface using dynamic programming method.Subsequently,an averaged A-scan analysis is performed to obtain the mean ET and the relative intensity ofdermis indicating the corresponding vascular density.This approach is currently successfullyapplied in clinical diagnosis and shows promising guidance and assessment of PDT treatment.

Tetracysteine as a Reporter for Gene Therapy

Objective To study the feasibility of using tetracysteine （TC） reporter in gene therapy. Methods Effects of TC reporter and conventional reporter genes encoding green fluorescence protein （GFP） and luciferase （Luc） on expression and function of the therapeutic gene MGMT^P140K were compared. Cytotoxicity and drug resistance were studied by Western blot. TC reporter used in therapy was analyzed by flow cytometry （FCM）. Results The TC reporter had no toxicity to cells and neither affected the expression or activity of therapeutic gene as compared to GFP and Luc. TC could be used in blood sample detection. Conclusion TC is a new kind of reporter gene for lentiviral vector in future gene therapy.

Oncogenic role of Tc17 cells in cervical cancer development

BACKGROUND As one of the subsets of CD8+T cells,Tc17 cells have recently been identified and are characterized by the secretion of interleukin(IL)-17,which is related to inflammatory diseases.AIM To assess the status of Tc17 cells in cervical cancer and investigate the biological function of Tc17 cells in cervical cancer development.METHODS Flow cytometry assay,immunohistochemistry,and immunofluorescence were performed to detect the levels and phenotype of Tc17 cells in blood and tumor samples from patients with cervical cancer.Prior to cell suspension culture,ELISA was carried out to measure the production of IL-6,IL-1β,IL-23,CXCL12,and IL-17 in tumor tissue supernatant and co-cultured supernatant of patients with cervical cancer.In addition,multivariate analysis was performed to identify factors associated with overall survival using the Cox proportional hazards model.RESULTS Compared with normal tissues,Tc17 cells specifically accumulated in tumor tissues of cervical cancer patients.Cancer cells produced a greater amount of IL-6,IL-1β,and IL-23,which in turn promoted Tc17 cell polarization.Unlike the traditional cytotoxic CD8^+T cells,Tc17 cells secreted IL-17,which subsequently promoted CXCL12 expression in tumor cells,eventually enhancing the proliferation and migration of tumor cells.Thus,the ratio of tumor-infiltrating Tc17 cells was highly correlated with poor clinical outcome in patients with cervical cancer.CONCLUSION Our data identified the oncogenic role of Tc17 cells in the development of cervical cancer.We propose that the ratio of Tc17 cells may be a useful index in the prognosis of patients with cervical cancer.

Elsinochrome A photosensitizers:Alternative drugs for photodynamic therapy

Photodynamic therapy(PDT)has already been a multifunctional modality for various tumors and nontumorous diseases.However,the development of photosensitizers is relatively delayed,compared with the tremendous progress in laser technology.Elsinochrome A(EA),a per-ylenequinonoid pigment from China,has all the typical advantages of perylenequinones.More-over,singlet oxygen quantum yield of EA is superior to other kinds of photosensitizers and EA could be artifially biosynthesized at present,which make it an alternative candidate for PDT.In.this review,the photophysics,photochemistry,photobiology and chemical or biological syntheses of EA photosensitizers are brielty presented.Besides,the future prospects of EA photosensitizers are also proposed.

Chemical composition of oscillatory zoned garnets from the largescale Mengya'a Pb–Zn skarn deposit: implications for fluid physicochemical conditions and formation

The Mengya’a Lead–zinc deposit is a large skarn deposit in the north of the eastern segment of Gangdese metallogenic belt.The garnet is the main altered mineral in the Mengya’a area.The color of the garnet varies from chartreuse to dark yellow brown and to russet.The brown garnet(Grt1)is related to pyrrhotite and chalcopyrite,and the green garnet(Grt2)is associated with lead–zinc mineralization.LA-ICP-MS is the induced coupled plasma mass spectrometry.This paper has used this technique to investigate Grt1 and Grt2.Grt1 develops core–rim textures with strong oscillation zone occurring in rim,whereas Grt2lacks core–rim textures and featured by oscillation zone.LA–ICP–MS analysis shows that garnets of Mengya’a are rich in CaO(29.90–37.52%)and FeO(21.17–33.35%),but low in Al_(2)O_(3)(0.05–4.85%).The calculated end members belong to grandite(grossular–andradite)garnets andradite.The negative Al(IV)versus Fe^(3+),positive Al(IV)versus total Al stoichiometric number,the positive Al(IV)versus Fe^(3+),and the negative Al(IV)versus total REE,all indicate that the substitution of REEs in garnets is controlled by YAG.All Garnets are depleted in large lithophile elements(e.g.,Rb=0.00–4.01 ppm,Sr=0.03–8.56 ppm).The total REE in Grt1 core is high(ΣREE=233–625 ppm),with HREE enriched pattern(LREE/HREE=0.33–1.69)and weak negative Eu anomalies(δEu=0.21–0.47).In contrast,the total REEs in the Grt1 rim and Grt2 are low(ΣREE=12.4–354 ppm;ΣREE=21.0–65.3 ppm),with LREE enriched pattern(LREE/HREE=0.54–34.4;LREE/HREE=11.4–682)and positive Eu anomalies(δEu=0.35–27.2;δEu=1.02–30.7).After data compilation of garnet chemicals,we found that the early fluid responsible for the core of Grt1 was a relatively closed and chloride-depleted fluid system.It was close-to-neutral,with a low water–rock ratio.The core of garnet was formed by fluid diffusion in metasomatic processes.The fluid was changed into a relatively open system with reduced,chloride-rich,and weakacid fluid.It was fluid infiltration and metasomatism that resulted in the formation of Grt1 rim and Grt2.

Effects of pulse width and repetition rate of pulsed laser on kinetics and production of singlet oxygen luminescence

Pulsed and continuous-wave(CW)lasers have been widely used as the light sources for photodynamic therapy(PDT)treatment.Singlet oxygen(^(1)O_(2))is known to be a major cytotoxic agent in type-II PDT and can be directly detected by its near-infrared luminescence at 1270 nm.As compared to CW laser excitation,the effiects of pulse width and repetition rate of pulsed laser on the kinetics and production of^(1)O_(2)luminescence were quantitatively studied during photosensitization of Rose Bengal.Significant di®erence in kinetics of^(1)O_(2)luminescence was found under the excitation with various pulse widths of nanosecond,microsecond and CW irradiation with power of 20mW.The peak intensity and duration of^(1)O_(2)production varied with the pulse widths for pulsed laser excitation,while the^(1)O_(2)was generated continuously and its production reached a steady state with CW excitation.However,no significant di®erence(P>0:05)in integral^(1)O_(2)production was observed.The results suggest that the PDT efficacy using pulsed laser may be identical to the CW laser with the same wavelength and the same average°uence rate below a threshold in solution.

Immobilization of Trehalose Synthase on Mesoporous Molecular Sieve

[ Objective] This study aimed to explore the immobitizatian of trehalose synthase on mesoporous molecular sieves. [ Method] With trehalose synthase produced by genetically engineered bacteria as experimental material, rnesoporous molecular sieve MCM-41 was used as a carrier for immobilization of trehalase syn- thase. Properties of trehalose synthase before and after immobilization were compared. [ Result ] Trehalose synthase could be immohihzed on mesoporous molecular sieve MCM-41 by using physical adsorption method. Immobilization of trehalose synthase achieved the best effect at pH 3.0, with enzyme amount of 62.5 mg/g and immobilization duration of 12 h. Compared with the free u, ehalose synthase, immobilized trehalose synthase showed significantly improved pH stability and thermal stability with repeatable operation, which was conducive to the utilization and storage of enzyme. [ Conclusion] This study provided theoretical basis for the devel- opment of new immobilized trehalose synthase.