Ce-Based Nanoparticles Loaded with Cisplatin for Tumour Radiotherapy

2020 ◽  
Vol 16 (10) ◽  
pp. 1482-1494
Author(s):  
Li Sun ◽  
Chang Jiang ◽  
Wenhai Li ◽  
Zelai He ◽  
Gengming Wang ◽  
...  
Keyword(s):  
Photoelectric Effect ◽  
Inhibitory Effect ◽  
Precipitation Method ◽  
Treatment Mode ◽  
X Ray ◽  
Transmission Electron ◽  
Good Biocompatibility ◽  
Synergistic Inhibitory Effect

The combination of radiotherapy and chemotherapy is a common and useful treatment mode for tumours. But traditional methods inevitably lead to a variety of side effects. A drug delivery system (DDS), which has good biocompatibility and strong anti-tumour ability, is expected to solve this problem. Studies have shown that Ce-based nanoparticles (NPs) have good radiosensitization effect through the photoelectric effect. Hence, cisplatin-loaded LiLuF4 :Ce3+scintillation NPs (NP + Cis) were first constructed in this study, which was synthesized by the crystal precipitation method and characterized by transmission electron microscopy (TEM). Subsequently, its toxicity was verified, and the radiosensitization effect and basic radiosensitization mechanism on tumour cells and tumour-bearing mice were researched. Results showed that NP + Cis triggered massive DNA damage and effectively inhibited cell viability in vitro under the exposure of X-ray irradiation (IR). Moreover, the experiments in vivo showed that the NP + Cis had higher biosafety, which could absorb enough irradiation and produce a synergistic inhibitory effect on tumours through the releasing of Cis. NP + Cis can improve the performance of DDS in chemoradiotherapy.

Dialysis Preparation of Zinc-Substituted Nano-Hydroxyapatite and Its Characterization

2007 ◽  
Vol 330-332 ◽  
pp. 219-222 ◽  
Author(s):  
Sheng Min Zhang ◽  
W. Hu ◽  
W. Zhou ◽  
J. Li ◽  
Y.H. Liu ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Limited Range ◽  
Transmission Electron Microscopy Observation ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Microscopy Observation ◽  
X Ray ◽  
Zinc Fractions ◽  
Transmission Electron

Nano-sized zinc-substituted hydroxyapatite (nano-ZnHA) has stimulatory effect on bone formation and inhibitory effect on osteoclastic bone resorption in vivo. Nano-ZnHA with serial zinc fractions (0, 2, 5, 10 mol%) were synthesized by an improved precipitation method based on dialysis process. Transmission electron microscopy observation indicated that the increase of Zn fraction led to smaller crystallite. X-ray diffraction of the products revealed that some typical characteristic peaks of HA displayed when the Zn fraction was below 10%. Fourier transform infrared spectroscopy showed that the bending peaks of the group-OH in HA became wider with the increase of Zn fraction and it disappeared at 10 mol%. The current work demonstrated that zinc could substitute for calcium into hydroxyapatite in the limited range of composition by using dialysis process.

The Influence of Hydrophilic Decoration on X-ray Excited Luminescence Nanoparticles to Singlet Oxygen Production

NANO ◽  
2020 ◽  
Vol 15 (07) ◽  
pp. 2050092
Author(s):  
Xiaosheng Zhu ◽  
Yi Tian ◽  
Lei Dai ◽  
Qiaofeng Wang ◽  
Mei Shi ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Exchange Reaction ◽  
X Ray ◽  
Good Biocompatibility ◽  
Place Exchange ◽  
High Concentrations ◽  
Excited Luminescence ◽  
Tumor Inhibition Rate

(1) Background: Though X-ray excited photodynamic therapy (X-PDT) breakthrough the bottom neck of PDT application in deep tumor by overcoming light penetration depth limitation, the quantum yield of the hydrophilic X-PDT nanoparticles (NPs) still hampered its further application in vivo. Thus, establishing a proper hydrophilic decoration method which can maximally maintain the quantum yield of X-ray excited luminescent NPs is of urgent demand. (2) Methods: We synthesized NaGdF4: [Formula: see text] (NGF) as X-ray excited luminescent NPs and conducted hydrophilic decoration by two hydrophilic ligands, polyethylene glycol-NH2 (PEG) and cysteamine (Cy) via place exchange reaction, and coupled with photosensitizer (MC540) to form a X-PDT nanosystem. We also conducted experiments in vitro and in vivo to evaluate the efficacy of the X-PDT system. (3) Results: Both PEG and Cy decoration NPs presented excellent emission intensity, which could well excite the coupled photosensitizer MC540 to generate significant X-PDT efficacy under low-dose X-ray radiation. Especially for the NGF-Cy-MC540 treatment group, the cell viability reduced to [Formula: see text]% under 0.3[Formula: see text]Gy radiation and [Formula: see text]% under only 0.1[Formula: see text]Gy radiation, which is the lowest radiation dosage in the literature reports so far. In vivo experiment showed about 36% of tumor inhibition rate under 0.3[Formula: see text]Gy X-ray. Besides, no biotoxicity was observed in NGF groups even in high concentrations, demonstrating good biocompatibility. (4) Conclusions: The hydrophilic decoration method by Cy or PEG via place exchange reaction may pave a brand new way and strategy for X-PDT further clinical application.

scholarly journals Secretory protein decondensation as a distinct, Ca2+-mediated event during the final steps of exocytosis in Paramecium cells.

1981 ◽  
Vol 88 (1) ◽  
pp. 179-188 ◽  
Author(s):  
M Bilinski ◽  
H Plattner ◽  
H Matt
Keyword(s):  
Intact Cell ◽  
Scanning Transmission Electron Microscope ◽  
Secretory Protein ◽  
Condensed State ◽  
Optimal Timing ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission

The contents of secretory vesicles ("trichocysts") were isolated in the condensed state from Paramecium cells. It is well known that the majority portion of trichocysts perform a rapid decondensation process during exocytosis, which is visible in the light microscope. We have analyzed this condensed leads to decondensed transition in vitro and determined some relevant parameters. In the condensed state, free phosphate (and possibly magnesium) ions screen local surplus charges. This is supported by x-ray spectra recorded from individual trichocysts (prepared by physical methods) in a scanning transmission electron microscope. Calcium, as well as other ions that eliminate phosphate by precipitation, produces decondensation in vitro. Under in vivo conditions, Ca2+ enters the vesicle lumen from the outside medium, once an exocytic opening has been formed. Consequently, within the intact cell, membrane fusion and protein decondensation take place with optimal timing. Ca2+ might then trigger decondensation in the same way by precipitating phosphate ions (as it does in vitro) and, indeed, such precipitates (again yielding Ca and P signals in x-ray spectra) can be recognized in situ under trigger conditions. As decondensation is a unidirectional, rapid process in Paramecium cells, it would contribute to drive the discharge of the secretory contents to the outside. Further implications on the energetics of exocytosis are discussed.

Loading of siRNA on Magnetic PLL-Fe2O3@SiO2 Nanocomposites and their Transfection In Vitro

2014 ◽  
Vol 1053 ◽  
pp. 444-449
Author(s):  
Xue Wen Cui ◽  
Gang Cheng ◽  
Rui Jiang Liu ◽  
Li Wei Wang ◽  
Yan Shuai Wang
Keyword(s):  
Electron Microscope ◽  
Precipitation Method ◽  
Blue Staining ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sd Rat ◽  
Gene Carriers ◽  
Transmission Electron ◽  
Co Precipitation

The magnetic Fe2O3 nanoparticles were prepared by co-precipitation method with FeCl3 and NaOH as starting reagents. The surface of Fe2O3 nanoparticles was modified with tetraethyl orthosilicate. Fe2O3@SiO2 nanocomposites were calcined at 600 °C. The nanocomposites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). The PLL-Fe2O3@SiO2 (SMNP) was prepared by modifying with poly-L-lysine on the surface. The SMNP combined with plasmid siRNA by static electrical charges as one of gene carriers was transfected into SD rat neurons. The results of fluorescence microscope and Prussian blue staining show that SMNP can effectively enter cells. Therefore, SMNP are one kind of novel and effective gene carriers, it can transfect the plasmid which carries the siRNA into SD rats neurons in vitro.

Enhanced 5-fluorouracil cytotoxicity in high COX-2 expressing hepatocellular carcinoma cells by wogonin via the PI3K/Akt pathway

2013 ◽  
Vol 91 (4) ◽  
pp. 221-229 ◽  
Author(s):  
Li Zhao ◽  
Yun-Ying Sha ◽  
Qing Zhao ◽  
Jing Yao ◽  
Bin-Bin Zhu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Human Tumor ◽  
Inhibitory Effect ◽  
Chemotherapeutic Agents ◽  
Carcinoma Cells ◽  
Antitumor Effects ◽  
Synergistic Inhibitory Effect ◽  
Cox 2

Combination therapies may increase the antitumor effects and reduce the adverse effects for the treatment of hepatocellular carcinoma. In this study, we determined the effects of 5-fluorouracil alone or in combination with wogonin in vitro and in vivo, and we investigated the possible mechanisms. The combination of these 2 drugs led to a decrease in survival and a significant synergistic inhibitory effect on high COX-2 expression in SMMC-7721 hepatocellular carcinoma (HCC) cells. Furthermore, the results show that this combination inhibits COX-2 expression and increases sensitivity to chemotherapeutic agents partly through regulating the PI3K/Akt signaling pathway. Moreover, the combination treatment caused a significant growth inhibition of human tumor xenografts in vivo. In conclusion, wogonin may increase the cytotoxicity of some antineoplastic agents and it can be used in combination with these agents as a novel therapeutic regimen for HCC treatment.

scholarly journals Synthesis, characterization, biological activities, and catalytic applications of alcoholic extract of saffron (Crocus sativus) flower stigma-based gold nanoparticles

2021 ◽  
Vol 10 (1) ◽  
pp. 230-245
Author(s):  
Fahad A. Alhumaydhi ◽  
Ibrahim Khan ◽  
Abdur Rauf ◽  
Muhammad Nasimullah Qureshi ◽  
Abdullah S. M. Aljohani ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Biological Activities ◽  
Inhibitory Effect ◽  
Biological Properties ◽  
Crocus Sativus ◽  
Alcoholic Extract ◽  
X Ray ◽  
Vis Spectroscopy

Abstract Currently, nanotechnology is gaining massive attention compared to conventional methods as the biosynthesis of plant-based nanoparticles is considered safe, effective, and ecofriendly. Therefore, keeping in view the importance of nanotechnology, the present study was designed to synthesize, characterize, and evaluate the biological effectiveness of saffron stigma-based gold nanoparticles (SS-AuNPs) for their in vitro and in vivo biological properties. These gold nanoparticles were characterized by UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The highest antibacterial effect was observed by the saffron extract against Escherichia coli (22 mm). SS-AuNPs significantly inhibited the activity of enzyme urease (54.98%) and CA-II (64.29%). However, the nonsignificant inhibitory effect was observed in the case of α-chymotrypsin. Maximum analgesic (84.98%) and antiinflammatory (88.98%) effects were observed for SS-AuNPs (10 mg/kg). Similarly, SS-AuNPs demonstrated a significant (P < 0.01) sedative effect at all tested doses.

scholarly journals Synthesis, Characterization, and Biodistribution of GdF3:Tb3+@RB Nanocomposites

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 569
Author(s):  
Oleg E. Polozhentsev ◽  
Ilia A. Pankin ◽  
Darya V. Khodakova ◽  
Pavel V. Medvedev ◽  
Anna S. Goncharova ◽  
...  
Keyword(s):  
Rose Bengal ◽  
Electrostatic Interactions ◽  
Cost Effective ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
X Ray ◽  
Transmission Electron ◽  
Size And Morphology ◽  
Peg Coating

Herein we report the development of a nanocomposite for X-ray-induced photodynamic therapy (X-PDT) and computed tomography (CT) based on PEG-capped GdF3:Tb3+ scintillating nanoparticles conjugated with Rose Bengal photosensitizer via electrostatic interactions. Scintillating GdF3:Tb3+ nanoparticles were synthesized by a facile and cost-effective wet chemical precipitation method. All synthesized nanoparticles had an elongated “spindle-like” clustered morphology with an orthorhombic structure. The structure, particle size, and morphology were determined by transmission electron microscopy (TEM), X-ray diffraction (XRD), and dynamic light scattering (DLS) analysis. The presence of a polyethylene glycol (PEG) coating and Rose Bengal conjugates was proved by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), and ultraviolet–visible (UV-vis) analysis. Upon X-ray irradiation of the colloidal PEG-capped GdF3:Tb3+–Rose Bengal nanocomposite solution, an efficient fluorescent resonant energy transfer between scintillating nanoparticles and Rose Bengal was detected. The biodistribution of the synthesized nanoparticles in mice after intravenous administration was studied by in vivo CT imaging.

Probenecid Inhibits Platelet Responses to Aggregating Agents in Vitro and Has a Synergistic Inhibitory Effect with Penicillin G

1996 ◽  
Vol 76 (02) ◽  
pp. 239-244 ◽  
Author(s):  
M A Packham ◽  
M L Rand ◽  
D W Perry ◽  
D H Ruben ◽  
R L Kinlough-Rathbone
Keyword(s):  
Platelet Activating Factor ◽  
Anion Channel ◽  
Inhibitory Effect ◽  
Penicillin G ◽  
Dependent Manner ◽  
Fura 2 ◽  
Synergistic Inhibitory Effect ◽  
Dose Dependent

SummaryProbenecid is an anion channel blocker and uricosuric agent, originally developed to slow the rate of excretion of penicillin. It is now also administered with many other drugs to reduce their required dosages. Recently, probenecid (2.5 mM) has been used to prevent leakage of fura-2 or fluo-3 when these indicators of cytosolic Ca2+ levels have been introduced into cells. However, we found that probenecid markedly inhibited the increases in cytosolic Ca2+ caused by ADP, thrombin, the thrombin receptor-activating peptide (SFLLRN, TRAP), ADP, sodium arachidonate, the thromboxane A2 (TXA2) mimetic U46619, and platelet-activating factor (PAF). This finding precluded the use of probenecid with platelets in measurements of cytosolic Ca2+ with indicators such as fura-2. We then investigated the effects of probenecid on aggregation and release of 14C-serotonin from prelabeled platelets. Responses to all the agonists were inhibited by 2.5 mM probenecid, but concentrations as low as 0.25-0.5 mM inhibited responses to agonists that act largely via TXA2 (collagen, sodium arachidonate and U46619). Collagen-induced TXA2 formation was inhibited in a dose-dependent manner. Responses of aspirin-pretreated platelets to thrombin, SFLLRN, U46619 and PAF were also inhibited by probenecid, indicating that prevention of TXA2 formation does not account for all the inhibitory effects. The combination of probenecid with penicillin G produced additive or synergistic inhibition of platelet responses; responses dependent on TXA2 were synergistically inhibited by concentrations of the drugs that are reached in vivo. The synergistic inhibitory effect of probenecid on platelet functions could further impair hemostasis if it has already been partially compromised by the administration of other drugs.

scholarly journals Effect of Flavonoid-Coated Gold Nanoparticles on Bacterial Colonization in Mice Organs

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1769 ◽  
Author(s):  
Sundus Riaz ◽  
Nosheen Fatima Rana ◽  
Irshad Hussain ◽  
Tahreem Tanweer ◽  
Afrah Nawaz ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Bacterial Colonization ◽  
X Ray ◽  
Transmission Electron ◽  
Nano Drug Delivery ◽  
Vis Spectroscopy ◽  
Scanning Transmission ◽  
Synthesis Approach

Multidrug resistance (MDR) has been a potentiator for the exploration of antibiotics. Nano drug delivery systems have opened new avenues to overcome this challenge. Although antibacterial nanocarriers are extensively realized, their effect on the bacteria residing inside the tissues and their toxicity is rarely explored. This study investigated the effects of flavonoid coated gold nanoparticles (FAuNPs) on the colonization of Enterococcus faecalis in the mouse liver and kidneys. Flavonoids were extracted from the leaves of Berberis lycium Royle and used to stabilize gold following a green synthesis approach. FAuNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), X-ray powder diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). FAuNPs showed significantly higher reduction in bacterial counts in in-vitro and in-vivo in mice organs as compared to the free flavonoids owing to their biocompatibility and effectiveness.

Sign in / Sign up

Export Citation Format

Share Document