Search

Copper-cysteamine (Cu-Cy) nanoparticles (NPs) are a new type of sensitizers that can be activated by UV light, X-rays, microwaves and ultrasound to produce reactive oxygen species for cancer treatment. Here, for the first time, we explored Cu-Cy NPs for bacteria inactivation by treating gram-positive bacteria (methicillin-resistant Staphylococcus aureus and Enterococcus faecalis ) and gram-negative bacteria ( Escherichia coli and Acinetobacter baumannii ), respectively. The results show that Cu-Cy NPs are very effective in killing gram-positive bacteria but are quite limited in killing gram-negative bacteria yet. The major killing mechanism is cell damage by singlet oxygen and Cu-Cy NPs are potential agents for bacteria inactivation.

Photodynamic therapy (PDT), a treatment that uses a photosensitizer, molecular oxygen, and light to kill target cells, is a promising cancer treatment method. However, a limitation of PDT is its dependence on light that is not highly penetrating, precluding the treatment of tumors located deep in the body. Copper-cysteamine nanoparticles are a new type of photosensitizer that can generate cytotoxic singlet oxygen molecules upon activation by X-rays. In this paper, we report on the use of copper-cysteamine nanoparticles, designed to be targeted to tumors, for X-ray-induced PDT. In an in vivo study, results show a statistically significant reduction in tumor size under X-ray activation of pH-low insertion peptide-conjugated, copper-cysteamine nanoparticles in mouse tumors. This work confirms the effectiveness of copper-cysteamine nanoparticles as a photosensitizer when activated by radiation and suggests that these Cu-Cy nanoparticles may be good candidates for PDT in deeply seated tumors when combined with X-rays and conjugated to a tumor-targeting molecule., Competing Interests: The authors declare no conflict of interest.

Aim: To clarify the effectiveness and safety of x-ray-activated photodynamic therapy (X-PDT) for cutaneous squamous cell carcinoma (SCC) and melanoma. Materials & methods: Copper-cysteamine nanoparticles were used as a photosensitizer of X-PDT. The dark toxicity and cytotoxicity were studied in vitro. Tumor volume, microvessel density and acute toxicity of mice were evaluated in vivo . Results: Without x-ray irradiation, copper-cysteamine nanoparticles were nontoxic for keratinocyte cells. XL50 cells (SCC) were more sensitive to X-PDT than B16F10 cells (melanoma). X-PDT successfully inhibited the growth of SCC in vivo (p < 0.05), while the B16F10 melanoma was resistant. Microvessel density in SCC tissue was remarkably reduced (p < 0.05). No obvious acute toxicity reaction was observed. Conclusion: X-PDT is a safe and effective treatment for SCC.

Photodynamic therapy (PDT) and photothermal therapy (PTT) have been emerging as attractive and promising methods for tumor treatment in clinical approaches. CuS nanoparticles are effective and cost-effective agents for PTT. Recently, it was observed that CuS nanoparticles are also excellence candidates for PDT. However, the mechanisms for CuS nanoparticles as PDT agents have never been discussed. The goal here is to explore the killing mechanisms of CuS nanoparticles as PTT and PDT agents. CuS nanoparticles were synthesized by a simple wet chemistry method by coating with amphiphilic polymer and examined for their therapeutic potential on lung adenocarcinoma cell line SPC-A-1 in vitro and in vivo using a murine cancer model. The CuS nanoparticles produce heat as well as reactive oxygen species (ROS) when excited by 808nm laser and show strong anticancer effects both in vitro and in vivo. The heating effects and release of copper ions from CuS upon heating in the tumor acidic environments are the main mechanisms for the generation of reactive oxygen species which are lethal bullets for cancer destruction. As a dual-function agent for PTT and PDT, CuS nanoparticles are promising phototherapy agents for cancer treatment., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Photodynamic therapy (PDT) has attracted ever-growing attention as a promising modality for cancer treatment. However, due to poor tissue penetration by light, photodynamic therapy has rarely been used for deeply situated tumors. This problem can be solved if photosensitizers are activated by microwaves (MW) that are able to penetrate deeply into tissues. Here, for the first time, we report microwave-induced photodynamic therapy and exploit copper cysteamine nanoparticles as a new type of photosensitizer that can be activated by microwaves to produce singlet oxygen for cancer treatment. Both in vitro and in vivo studies on a rat osteosarcoma cell line (UMR 106-01) have shown significant cell destruction using copper cysteamine (Cu-Cy) under microwave activation. The heating effects and the release of copper ions from Cu-Cy upon MW stimulation are the main mechanisms for the generation of reactive oxygen species that are lethal bullets for cancer destruction. The copper cysteamine nanoparticle-based microwave-induced photodynamic therapy opens a new door for treating cancer and other diseases.

Chemical derived graphene oxide, an atomically thin sheet of graphite with two-dimensional construction, offers interesting physical, electronic, thermal, chemical, and mechanical properties that are currently being explored for advanced physics electronics, membranes, and composites. Herein, we study graphene quantum dots (GQD) with the blue photoluminescence under various parameters. The GQD samples were prepared at different temperatures, and the blue photoluminescence intensity of the solution improved radically as the heating temperatures increased. Concerning PL peak and intensity of the quantum dots, the results demonstrated dependence on time under heating, temperature of heating, and pH adjusted by the addition of sodium hydroxide. After hydrothermal synthesis routes, the functional groups of graphene oxide were altered the morphology showed the stacking configuration, and self-assembled structure of the graphene sheets with obvious wrinkles appeared at the edge structures. In addition, absorption, PL, and PLE spectra of the graphene quantum dots increase with different quantities of sodium hydroxide added. Finally, using GQD to target PNTIA cells was carried out successfully. High uptake efficiency and no cytotoxic effects indicate graphene quantum dots can be suitable for bio-targeting.

We developed new optic devices - singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light - for improvement of visual system functions. Tb(3+) or Eu(3+) singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and thereby provide extra visible light to the eye. In zebrafish (wild-type larvae and adult control animals, retinal degeneration mutants, and light-induced photoreceptor cell degeneration models), the use of Tb(3+) or Eu(3+) doped luminescence glass or CdS-QD coated glass lenses provide additional visible light to the rod and cone photoreceptor cells, and thereby improve the visual system functions. The data provide proof-of-concept for the future development of optic devices for improvement of visual system functions in patients who suffer from photoreceptor cell degeneration or related retinal diseases.

Human norovirus is a leading cause of acute gastroenteritis worldwide in a plethora of residential and commercial settings, including restaurants, schools, and hospitals. Methods for easily detecting the virus and for treating and preventing infection are critical to stopping norovirus outbreaks, and inactivation via nanoparticles (NPs) is a more universal and attractive alternative to other physical and chemical approaches. Using norovirus GI.1 (Norwalk) virus-like particles (VLPs) as a model viral system, this study characterized the antiviral activity of Au/CuS core/shell nanoparticles (NPs) against GI.1 VLPs for the rapid inactivation of HuNoV. Inactivation of VLPs (GI.1) by Au/CuS NPs evaluated using an absorbance-based ELISA indicated that treatment with 0.083 μM NPs for 10 min inactivated ~50% VLPs in a 0.37 μg/ml VLP solution and 0.83 μM NPs for 10 min completely inactivated the VLPs. Increasing nanoparticle concentration and/or VLP-NP contact time significantly increased the virucidal efficacy of Au/CuS NPs. Changes to the VLP particle morphology, size, and capsid protein were characterized using dynamic light scattering, transmission electron microscopy, and Western blot analysis. The strategy reported here provides the first reported proof-of-concept Au/CuS NPs-based virucide for rapidly inactivating human norovirus.

Aim: In this study, Ce(3+)-doped lanthanum(III) fluoride (LaF3:Ce(3+)) nanoparticles were synthesized by a wet-chemistry method in dimethyl sulfoxide (DMSO) and their application as an intracellular light source for photodynamic activation was demonstrated., Materials & Methods: The LaF3:Ce(3+)/DMSO nanoparticles have a strong green emission with a peak at approximately 520 nm, which is effectively overlapped with the absorption of protoporphyrin IX (PPIX). The nanoparticles were encapsulated into poly(D,L-lactide-co-glycolide (PLGA) microspheres along with PPIX. Upon irradiation with x-rays (90 kV), energy transfer from the LaF3:Ce(3+)/DMSO nanoparticles to PPIX occurs and singlet oxygen is generated for cancer cell damage., Results: The LaF3:Ce(3+)/DMSO/PLGA or LaF3:Ce(3+)/DMSO/PPIX/PLGA microspheres alone caused only sublethal cytotoxicity to the cancer cells. Upon x-ray irradiation, the LaF3:Ce(3+)/DMSO/PPIX/PLGA microspheres induced oxidative stress, mitochondrial damage and DNA fragmentation on prostate cancer cells (PC3)., Discussion: The results indicate that x-rays can activate LaF3:Ce(3+) and PPIX nanocomposites, which can be a novel method for cancer destruction.

Cu(2+) and Co(2+) co-doped zinc sulfide water-soluble nanoparticles (ZnS:Cu,Co) were prepared and their afterglow luminescence was observed and reported for the first time. The nanoparticles have a cubic zinc blende structure with average sizes of about 4 nm as determined by high-resolution transmission electron microscopy (HRTEM) and x-ray diffraction (XRD). In the photoluminescence, two emission peaks are observed at 470 and 510 nm. However, in the afterglow, only one peak is observed at around 525 nm. The blue emission at 470 nm is from surface states and the green emission at 525 nm is from Cu(2+). This means that Cu(2+) is responsible for the afterglow from the nanoparticles, while the co-doping of Co(2+) is critical for the afterglow because no afterglow could be seen without co-doping with Co(2+). The successful observation of the afterglow from water-soluble nanoparticles may open up new applications of afterglow phosphors in biological imaging, detection and treatment.

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver and occurs predominantly in patients with underlying chronic liver disease and cirrhosis. HCC is now the third leading cause of cancer deaths worldwide, with over 500,000 people affected. However, there is no complete effective (ideal) treatment for liver cancer yet, and the new methods are expected to be discovered. Herein, for the first time, we report the anti-HCC effects of copper-cysteamine nanoparticles (Cu-Cy NPs), a new type of photosensitizers. An in vitro 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay shows that Cu-Cy NPs could significantly reduce the activity of HepG2 cells at a very low dose after a short time of ultraviolet radiation. In addition, we found that cell death was induced by Cu-Cy NPs, which is associated with cellular apoptosis. This implied that apoptosis might be the main mechanism of the Cu-Cy's anti-HCC activity. Furthermore, we found that Cu-Cy NPs obviously inhibited the tumor growth in vivo. More interestingly, we found that the soluble Cu-Cy NPs were able to enter exosomes which were secreted by tumor cells, and exosomes could be used to deliver Cu-Cy NPs to target tumor cells. All these observations suggest that Cu-Cy NPs have a good potential for cancer treatment. [ABSTRACT FROM AUTHOR]

Abstract: Sonodynamic therapy (SDT), as a newly emerging and promising modality for cancer treatment, has been extensively investigated but with limited therapeutic outcome because of the absence of highly efficient sonosensitizer. Copper–cysteamine (Cu–Cy), as a new sensitizer, has been reported for oxidative therapy which can be activated with light, X‐ray, or microwave. Herein, for the first time, Cu–Cy nanoparticles are reported as new sonosensitizers for SDT on breast cancer treatment. Upon exposure of Cu–Cy nanoparticles to ultrasound, a large quantity of reactive oxygen species (ROS) are generated for cancer cell destruction with a high SDT efficiency to induce cell apoptosis and necrosis as observed in vitro. In vivo animal studies show a significant inhibition of tumor growth for the xenografts of 4T1 cancer cells with the combination of 0.75 mg kg−1 Cu–Cy and ultrasound. Overall, the preliminary results show that Cu–Cy nanoparticles can significantly augment the levels of ROS induced by ultrasound, demonstrating Cu–Cy is a new kind of efficient sonosensitzers for SDT applications. Such therapeutic platform by integrating a noninvasive, highly safe, deep‐penetration ultrasound modality. and quickly developed versatile nanosensitizers for tumor eradication will facilitate SDT future clinical translation. [ABSTRACT FROM AUTHOR]

Nanosonosensitization by Using Copper-Cysteamine Nanoparticles Augmented Sonodynamic Cancer Treatment GLO:OLV/01dec22:ppsc202200155-fig-0001.jpg PHOTO (COLOR): 6 The in vivo ROS generation detected through fluorescence microscopy after different treatment. gl This correction does not change any results or conclusions of the original paper. B 2018 b , I 35 i , 1700378 DOI: 10.1002/ppsc.201700378 In the original version of Figure 6, the image of US (-) Cu-Cy (+) was mistakenly misplaced. [Extracted from the article]