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oe1(光电查) - 科学论文

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?? 中文(中国)
  • Fluorine-containing graphene quantum dots with a high singlet oxygen generation applied for photodynamic therapy

    摘要: Recently, graphene quantum dots (GQDs) have been extensively studied in biomedical areas such as bio-imaging, bio-sensing and photothermal therapy due to their superior optical and physiochemical properties compared to traditional organic biomarkers. Application of GQDs in photodynamic therapy (PDT) has been explored since 2014, but currently the main challenges are inadequate singlet oxygen (1O2) quantum yield (QY), poor solubility and biocompatibility. Herein, we report on the synthesis of a new kind of fluorine-containing GQDs (F-GQDs) by an oxidative cutting method using fluorinated graphite as the raw material. The as-synthesized F-GQDs sample demonstrates an average particle size of 2.1 nm with the fluorine doping content of 1.43%. The F-GQDs have a more excellent water solubility and biocompatibility than the GQDs, and emit strong green fluorescence at 365 nm excitation with the relative fluorescence QY of 13.72%. Moreover, the fluorescence imaging effect as well as photodynamic activity successfully tested in both in vitro HepG2 cell line model and a 3D multicellular spheroids model that mimics the tumour microenvironment. Further studies using UV-visible spectroscopy through the degradation of water-soluble 9,10-anthracenediyl-bis(methylene) dimalonic acid(ABDA) demonstrate that the F-GQDs sample generate 1O2 efficiently (QY = 0.49) under a visible light irradiation. Compared to non-fluorinated GQDs, the as-reported F-GQDs manifest to be a more promising photosensitizer for image-guided PDT.

    关键词: singlet oxygen,photodynamic therapy,biocompatibility,fluorine-containing,graphene quantum dots

    更新于2025-09-19 17:13:59

  • Insight into the efficiency of oxygen introduced photodynamic therapy (PDT) and deep PDT against cancers with various assembled nanocarriers

    摘要: Photodynamic therapy (PDT) has been used in the treatment of cancers and other benign diseases for several years in clinic. However, the hypoxia of tumors and the penetration limitation of excitation light to tissues can dramatically reduce the efficacy of PDT to cancers. To overcome these drawbacks, various assembled nanocarriers such as nanoparticles, nanocapsules, nanocrystals, and so on were introduced. The assembled nanocarriers have the ability of loading photosensitizers, delivering O2 into tumors, generating O2 in situ in tumors, as well as turning near-infrared (NIR) light, X-rays, and chemical energy into ultraviolet or visible light. Therefore, it is easy for the nanocarriers to improve the hypoxia microenvironment or increase the treatment depth of cancers, which will improve the efficiency of PDT to some degree. In recent years, a number of investigations were focused on these subjects. We will summarize the advances of nanocarriers in PDT, especially in O2 introduction PDT and deep PDT. The perspectives, challenges, and potential in translation of PDT will also be discussed.

    关键词: Oxygen introduction,Photodynamic therapy (PDT),Cancers,Nanocarriers,Deep PDT

    更新于2025-09-19 17:13:59

  • Photodynamic activation of irrigation (using different laser prototypes) on push out bond strength of fiber posts

    摘要: Background: To evaluate the influence of photodynamic therapy (PDT) and light activated irrigation (LAI) using different laser prototypes Er,Cr:YSGG (ECYL), Er:Yag (EYL), Nd-Yag (NYL) on pushout bond strength of Pre-fabricated fiber reinforced composite (PFRC) post to radicular dentin. Material and method: Fifty maxillary and mandibular teeth were collected, cleaned and decoronated. Canals were instrumented using crown-down technique. Flaring of canals was performed using protaper S1, SX files. F1, F2 and F3 files were utilized for finishing of canal preparations. Prepared root canals were dried and obturated with gutta percha. Teeth were placed vertically within the section of polyvinyl pipes using acrylic resin. Post space preparation was completed using peso-reamers. Based on the PDT and laser activated irrigation (LAI) with different laser prototypes, samples were divided into five groups of 10 specimens each. Group 1- PDT, group 2–5.25 % NaOCl (sodium hypochlorite) and 17 % EDTA (ethylene diamine tetra acetic acid), group 3–5.25 % NaOCl with 17 % EDTA and NYL, group 4–5.25 % NaOCl with 17 % EDTA and EYL ; and group 5–5.25 % NaOCl +17 % EDTA and ECYL. Fiber post were luted in root canals with self-etch dual cure cement and teeth were sectioned at three levels (apical, middle and coronal). Push-out test was performed by placing the specimens in universal testing machine. Failure analysis of debonded surfaces was evaluated using stereomicroscope at 40× magnification. Means and standard deviations of push out bond strength were assessed by one-way analysis of variance (ANOVA). Comparison between means of push out bond strength was evaluated using Tukey multiple comparison tests (p = 0.05). Result: The highest push out bond strength was observed in group 5 at all three levels, coronal (10.08 ± 0.74 MPa), middle (8.95 ± 0.94 MPa) and apical (6.00 ± 0.88 MPa). The lowest push out bond strength was demonstrated by group 2 at all levels, coronal (6.15 ± 1.22 MPa), middle (5.65 ± 0.95 MPa) and apical (2.25 ± 0.55 MPa). Intra-group comparison showed decrease in push out bond strength in the coronal to apical direction among all investigated groups. Inter-group comparison exhibited comparable push out bond strength at all three levels of root for group 1 and group 2 specimens (p > 0.05). Conclusion: LAI with different laser prototypes improved push out bond values of PFRC post to root dentin as an adjunct to NaOCl and EDTA treatment. PDT improved push out strength compared to conventional canal cleaning regime.

    关键词: Light activated irrigation,Bond failure,Photodynamic therapy,Push out bond strength,Laser prototypes

    更新于2025-09-19 17:13:59

  • A Nanosystem Loaded Perfluorohexane and Rose Bengal Coupled Upconversion Nanoparticles for Multimodal Imaging and Synergetic Chemo-Photodynamic Therapy in Cancer

    摘要: Theranostics is a new trend integrating diagnostic and therapeutic functions in tumour research. Theranostic nanoparticles that enabling both tumour imaging and drug delivery are a promising platform for image-guided cancer therapy. Photodynamic therapy (PDT) has great potential in synergy with traditional chemotherapy while facing great challenges due to hypoxia, poor targeting ability and limited penetration depth of visible light. To solve these problems, we presented a novel nanosystem of FA/UCNPs-RB/HCPT/PFH@Lipid (denoted as FURH-PFH-NPs), with a perfluorohexane (PFH) carrying rich oxygen core and a folic acid-modified lipid shell. The shell contains 10-hydroxycamptothecin (HCPT) and self-fluorescing photosensitizer compounds, namely, of upconversion nanoparticles and Rose Bengal (UCNPs-RB). In this study, FURH-PFH-NPs aggregated at SKOV3 cells (in vitro) and the nude xenograft tumour region when combined with folic acid receptor. When triggered by low-intensity focused ultrasound (LIFU), FURH-PFH-NPs released PFH, UCNPs-RB and HCPT. The above procedure was monitored through multimodal imaging, which simultaneously guided the tumour therapy. UCNPs-RB and PFH promoted the PDT effect under LIFU. Through PDT and HCPT, we obtained better therapeutic effects and good biosafety in SKOV3 nude xenograft tumours. FURH-PFH-NPs combined with LIFU and laser irradiation might be a promising strategy for ovarian cancer.

    关键词: Photodynamic therapy,Theranostics,ovarian cancer,multimodal imaging,nanoparticles

    更新于2025-09-19 17:13:59

  • Manganese‐doped green tea‐derived carbon quantum dots as a targeted dual imaging and photodynamic therapy platform

    摘要: In this work, manganese-doped carbon quantum dots (Mn-CQDs) have been synthesized through a one-pot hydrothermal method by using waste green tea. The Mn2+ dopants were introduced to impart magnetic resonance capability. Upon optimization of the experimental conditions, magnetofluorescent Mn-CQDs exhibit an excitation-dependent blue emission. The abundant functional groups on Mn-CQDs not only promote water solubility but also allow straightforward functionalization with amine groups. The amine-terminated Mn-CQDs were then subsequently conjugated to folic acid (FA) and chlorin e6 (Ce6) to obtain the Mn-CQDs@FA/Ce6 magnetofluorescent photodynamic therapy (PDT) agent. in vitro studies using three different cells indicated specific targeting of Mn-CQDs@FA/Ce6 to the overexpressing folate receptor human epithelial carcinoma cell line (HeLa) cancer cells. Furthermore, Mn-CQDs@FA/Ce6 enhanced magnetic resonance imaging (MRI) signal with an r2/r1 ratio of 5.77. Favorably, by using the Mn-CQDs@FA delivery system, active Ce6 can reach the cellular interior while its red fluorescence (FL) and reactive oxygen species generation can be retained, as has been verified by confocal microscopy. in vitro cell viability studies verified the biocompatibility of Mn-CQDs@FA/Ce6 nanohybrid with no significant toxicity up to 500 ppm while PDT treatment with 5 min irradiation (671 nm, 1 W cm?2) was effective in killing >90% of cells. The light-triggered Mn-CQDs@FA/Ce6 multifunctional hybrid can serve as a dual-modal FL/MRI probe and as an efficient PDT agent to detect and eradicate cancer cells remotely.

    关键词: Mn dopant,photoluminescence,carbon quantum dots,photodynamic therapy,MRI

    更新于2025-09-19 17:13:59

  • Preparation and characterization of seleniuma??decorated graphene quantum dots with high afterglow for application in photodynamic therapy

    摘要: Graphene quantum dots (GQDs) was synthesized using a simple, rapid and affordable method and decorated with selenium at different molar ratios for the first time to obtain an efficient sample for use in photodynamic therapy. Surface modification of GQDs was carried out using polyethylene glycol (PEG) for conjugation with protoporphyrin IX (PpIX). Synthesized GQDs (Se: 0.3%) at 180°C had an emission spectrum that fairly coincided with the absorption profile of PpIX. A relative decrease of about 62.48% in the emission intensity of anthracene was recorded under illumination with UVC light in the presence of GQDs (Se: 0.3%) and the reduction for clung GQDs (Se: 0.3%) and PpIX during 90 min was about 70.68%. Singlet oxygen (1O2) generation was examined using a chemical method that showed significant enhancement in decomposition rate constant in clung GQDs–PEG–PpIX compared with GQDs and PpIX alone. Afterglow over 600 s showed that GQDs (Se: 0.3%) could be effective for near skin and even deep tumours.

    关键词: photodynamic therapy,selenium,afterglow,protoporphyrin IX,graphene quantum dots

    更新于2025-09-19 17:13:59

  • The study of effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives

    摘要: To investigate the effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives (HPD) and provide theoretical basis for clinical photodynamic therapy (PDT). Human lung adenocarcinoma cell xenograft model in nude mice was established and randomly divided into four groups: control group, pure photosensitizer group, pure irradiation group, and photodynamic treatment group. The tumor volume growth was compared, and the tumor growth inhibition rate was calculated. HE staining was used for routine pathological observation of tumor sections, and gross conditions of cells, interstitium, and blood vessels in several groups of tumor tissues were observed. TUNEL staining was used to observe and compare the apoptosis induced by photodynamic therapy. Real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression level of angiogenesis-related factors VEGF, HIF-1α and apoptosis-related factors Bax and Bcl-2 mRNA in the transplanted tumor tissues. Western blot was employed to detect the expression of angiogenesis-related proteins VEGF, HIF-1α and apoptosis-related proteins Bax, Caspase-3, and Bcl-2. Compared with the other three groups, the tumor growth inhibition rate of the photodynamic treatment group was significantly increased and the difference was statistically significant (P < 0.05). HE staining showed that the animal model of lung adenocarcinoma A549 was successfully established. TUNEL staining revealed that more apoptotic cells were found in the photodynamic treatment group, and the apoptosis index was calculated. Compared with the other three groups, the difference was statistically significant (P < 0.05). RT-PCR results showed that compared with the other three groups, the mRNA expressions of VEGF, HIF-1α, and Bcl-2 in the photodynamic treatment group decreased, while the expression of Bax mRNA increased(P < 0.05), and the differences were statistically significant. Western blot results showed that protein expressions of VEGF, HIF-1α, and Bcl-2 decreased in the photodynamic treatment group, while protein expression level of Bax and Caspase-3 increased (P < 0.05), indicating statistically significant differences. The 630-nm laser mediated by hematoporphyrin derivatives can significantly inhibit the growth of human lung adenocarcinoma xenograft tumor in nude mice, the mechanism of which is related to the inhibition of tumor angiogenesis by down-regulating VEGF and HIF-1α gene expression, and the promotion of tumor apoptosis by up-regulating Bax, Caspase-3, and down-regulating Bcl-2 gene expression.

    关键词: Angiogenesis,Animal models,Lung adenocarcinoma,Photodynamic therapy,Apoptosis

    更新于2025-09-19 17:13:59

  • Retrospective study of photodynamic therapy for pulsed dye lasera??resistant porta??wine stains

    摘要: Pulsed dye laser-resistant port-wine stains present a therapeutic challenge. The aim of this study was to evaluate the efficacy and safety of photodynamic therapy for treating these lesions. A total of 67 patients with pulsed dye laser-resistant cervicofacial port-wine stains were retrospectively assessed after undergoing photodynamic therapy mediated with a combination of hemoporfin and 532-nm light. For objective evaluation of photodynamic therapy efficacy, first, the colorimetric changes in the port-wine stain lesions were evaluated according to the L*a*b* color coordinate system, then the values of color changes (DE) and blanching rate were calculated. For subjective evaluation of improvement, photographs taken before and after photodynamic therapy were evaluated by three independent assessors blindly. Patient satisfaction was also used as a factor in the subjective evaluation. Adverse events were recorded after treatment. The median DE decreased significantly from the pretreatment value of 13.42 to 9.90 at the 2-month follow up (P < 0.001). The median blanching rate of port-wine stains was 28.04% after an average of 1.21 sessions of photodynamic therapy. Based on the overall visual assessment, 46.2% patients showed excellent or good levels of improvement (>50% color blanching). Adverse events were minimal, transient and self-limiting. In conclusion, photodynamic therapy serves as an alternative means to treat pulsed dye laser-resistant port-wine stains.

    关键词: pulsed dye laser,pulsed dye laser resistance,treatment efficacy,photodynamic therapy,port-wine stain

    更新于2025-09-19 17:13:59

  • [IEEE 2019 International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON) - Novosibirsk, Russia (2019.10.21-2019.10.27)] 2019 International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON) - Theoretical Substantiation for the Original Technique of Photodynamic Fractional Laser Photothermolysis (PFLP) for Dermatology, based on Intradermal Transport of Photosensibilisers

    摘要: This review demonstrates the progress, current status and problems of photodynamic therapy and laser photothermolysis for various skin diseases and rejuvenation. These new minimally invasive technologies are detailed from the points of view of their advantages and disadvantages. Particular attention is paid to complications, associated with prolonged dermal phototoxicity after insufficient intravenous intradermal penetration of photosensibilisers after local application to skin. Finding a compromise between phototoxicity and insufficiency of local photosensibilisation we've developed a technical approach employed to overcome of limitations associated with targeted delivery of photosensibilisers into deep dermal layers. Intradermal delivery of photosensibilisers through so-called microthermal zones or dermal micropores, formed by focused pulse-periodic radiation of fiber laser, previously never used for photodynamic therapy of dermal disorders.

    关键词: photodynamic therapy,intradermal transport,rejuvenation,drug delivery,skin diseases,photothermolysis

    更新于2025-09-19 17:13:59

  • Comparative evaluation of photodynamic therapy using LASER or light emitting diode on cariogenic bacteria: An in vitro study

    摘要: Objective: The aim of this study was to evaluate in vitro the effect of photodynamic therapy (PDT) using LASER or light emitting diode (LED) on cariogenic bacteria (Streptococcus mutans [SM] and Lactobacillus casei [LC]) in bovine dentin. Materials and Methods: Twenty five fragments of dentin were contaminated with SM and LC strands and divided into five experimental groups according to the therapy they received (n = 5): C – control (no treatment), SCLED – no dye/LED application (94 J/cm2), SCLASER – no dye/LASER application (94 J/cm2), CCLED – dye/LED application (94 J/cm2) and CCLASER – dye/LASER application (94 J/cm2). The dye used was methylene blue at 10 mM. Dentin scrapes were harvested from each fragment and prepared for counts of colony forming units (CFU)/mL. The data were analyzed using Kruskal–Wallis, followed by Student–Newman–Keuls (α =0.05). Results: Regarding SM, groups CCLASER and CCLED showed a significant reduction in CFU/mL, which was statistically superior to the SCLASER, SCLED and C groups. Regarding LC, the groups CCLASER and CCLED caused a significant reduction in CFU/mL when compared with SCLASER, which showed intermediate values. SCLED and C had a lesser effect on reducing CFU/mL, where the former showed values similar to those of SCLASER. Conclusions: In conclusion, PDT combined with LASER or LED and methylene blue had a significant antimicrobial effect on cariogenic bacteria in the dentin.

    关键词: Lactobacillus casei,Streptococcus mutans,semi-conductor lasers,photodynamic therapy

    更新于2025-09-16 10:30:52