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Magnetic ferrite nanoparticles (MFNPs) have great application potential in biomedical fields such as magnetic resonance imaging, targeted drugs, magnetothermal therapy and gene delivery. MFNPs can migrate under the action of a magnetic field and target specific cells or tissues. However, to apply MFNPs to organisms, further modifications on the surface of MFNPs are required. In this paper, the common modification methods of MFNPs are reviewed, their applications in medical fields such as bioimaging, medical detection, and biotherapy are summarized, and the future application directions of MFNPs are further prospected.
Subject(s)
Ferric Compounds , Magnetic Resonance Imaging/methods , Magnetics , Magnetite Nanoparticles/therapeutic use , NanoparticlesABSTRACT
Diseases caused by trypanosomatid parasites affect millions of people mainly living in developing countries. Novel drugs are highly needed since there are no vaccines and available treatment has several limitations, such as resistance, low efficacy, and high toxicity. The drug discovery process is often analogous to finding a needle in the haystack. In the last decades a so-called rational drug design paradigm, heavily dependent on computational approaches, has promised to deliver new drugs in a more cost-effective way. Paradoxically however, the mainstay of these computational methods is data-driven, meaning they need activity data for new compounds to be generated and available in databases. Therefore, high-throughput screening (HTS) of compounds still is a much-needed exercise in drug discovery to fuel other rational approaches. In trypanosomatids, due to the scarcity of validated molecular targets and biological complexity of these parasites, phenotypic screening has become an essential tool for the discovery of new bioactive compounds. In this article we discuss the perspectives of phenotypic HTS for trypanosomatid drug discovery with emphasis on the role of image-based, high-content methods. We also propose an ideal cascade of assays for the identification of new drug candidates for clinical development using leishmaniasis as an example.
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Accurately delineating tumor boundaries is key to predicting survival rates of cancer patients and assessing response of tumor microenvironment to various therapeutic techniques such as chemotherapy and radiotherapy. This review discusses various strategies that have been deployed to accurately delineate tumor boundaries with particular emphasis on the potential of chemotherapeutic nanomaterials in tumor boundary delineation. It also compiles the types of tumors that have been successfully delineated by currently available strategies. Finally, the challenges that still abound in accurate tumor boundary delineation are presented alongside possible perspective strategies to either ameliorate or solve the problems. It is expected that the information communicated herein will form the first compendious baseline information on tumor boundary delineation with chemotherapeutic nanomaterials and provide useful insights into future possible paths to advancing current available tumor boundary delineation approaches to achieve efficacious tumor therapy.
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Microalgae is an easy-to-obtain natural biological material with many varieties and abundant natural reserves. Microalgae are rich in natural fluorescein, which can be used as a contrast agent for fluorescence imaging and photoacoustic imaging for medical imaging. With its active surface, microalgae can effectively adsorb functional molecules, metal elements, etc., and have good application prospects in the field of drug delivery. Microalgae can generate oxygen through photosynthesis to increase local oxygen concentration, reverse local hypoxia to enhance the efficacy of hypoxic tumors and promote wound healing. In addition, microalgae have good biocompatibility, and different administration methods have no obvious toxicity. This paper reviews the research progress on the biomedical application of microalgae in bioimaging, drug delivery, hypoxic tumor treatment, wound healing.
Subject(s)
Humans , Drug Delivery Systems , Hypoxia , Microalgae , Oxygen , Wound HealingABSTRACT
Metal-organic frameworks (MOFs) are porous crystalline polymers constructed from the coordination reaction between organic ligands and metal ions. Due to their advantages: adjustable periodic pore structure, large specific surface area and easy functional modification, etc., MOFs have been widely used in the fields of gas storage/separation, catalysis, sensing, biological imaging and drug delivery. In recent years, MOFs have shown great potential in disease diagnosis and treatment. This review summarizes the application of MOFs in the fields of bio-sensing, cell imaging, in vivo imaging, drug delivery, etc., discusses the problems and corresponding solutions in the application of MOFs for biomedicine. We hope this review can provide reference for the designing new methods for disease diagnosis and treatment.
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BACKGROUND: Biopolymeric in situ hydrogels play a crucial role in the regenerative repair and replacement of infected or injured tissue. They possess excellent biodegradability and biocompatibility in the biological system, however only a few biopolymeric in situ hydrogels have been approved clinically. Researchers have been investigating new advancements and designs to restore tissue functions and structure, and these studies involve a composite of biometrics, cells and a combination of factors that can repair or regenerate damaged tissue. METHODS: Injectable hydrogels, cross-linking mechanisms, bioactive materials for injectable hydrogels, clinically applied injectable biopolymeric hydrogels and the bioimaging applications of hydrogels were reviewed. RESULTS: This article reviews the different types of biopolymeric injectable hydrogels, their gelation mechanisms, tissue engineering, clinical applications and their various in situ imaging techniques. CONCLUSION: The applications of bioactive injectable hydrogels and their bioimaging are a promising area in tissue engineering and regenerative medicine. There is a high demand for injectable hydrogels for in situ imaging.
Subject(s)
Biopolymers , Hydrogels , Hydrogels , Regenerative Medicine , Tissue EngineeringABSTRACT
Functional groups may change the electrical characteristics of graphene quantum dots,thus leading to the improvement of their properties and related applications. To improve the optical properties,we designed and synthesized pentaethylene hexamine and dodecylamine functionalized graphene quantum dots (PEHA-GQD-DA). Citric acid was mixed with pentaethylene hexamine and heated at 170℃ for 0.5 h. Then dodecylamine was added and the reaction was continued at 160℃ for 1.5 h to obtain PEHA-GQD-DA. The Yesults revealed that the PEHA-GQD-DA was composed of the graphene sheets from 1 nm to 3 nm,and their edges contained abundant functional groups. The introduction of pentaethylene hexamine greatly improved the fluorescence emission. The fluorescence quantum yield reached 72.7%,which was much higher than that of the GQD prepared by the thermal hydrolysis of single citric acid. The introduction of dodecylamine created a special amphiphilic structure that allows the quantum dots more likely to enter cell through the phospholipid bilayer of cell membrane. The PEHA-GQD-DA exhibited an excellent optical behavior for pH value of the medium. Within pH range of 1.0-6.5, the fluorescence intensity increased with the increase of pH value. The fluorescence spectrum sensitively changed with the change of pH value. There was a good linear relationship between the maximum emission wavelength and the pH value. When the pH was in the range of 6.5-12.0,the fluorescence spectrum didn't change with the change of pH value. However, its fluorescence intensity linearly decreased with the increase of pH value. The existence of common inorganic ions and organic small molecules does not interfere with pH response of the quantum dots. The PEHA-GQD-DA has been successfully applied to fluorescent detection of pH value in water samples and Hela cell imaging.
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OBJECTIVE To explore a novel pH-sensitive fluorescent probe for in vivo tumor imaging. METHODS Zn5 were obtained in 140℃ after mixed with MeOH, water, Zn(NO3)2 · 6H2O, H4L and trimethylamine. The fluorescence spectra of Zn5 with the same concentration in different pH aqueous solutions were detected. And the stability of Zn5 was investigated by time dependent fluorescence emission spectra of Zn5 in BSA aqueous solution and 5.0% serum solution. Then, the cytotoxicity of Zn5 was detected by MTT assays. To clarify whether a similar fluorescence response occurs in biological organisms, HeLa cells were pretreated with probe Zn5 (0.5 μmol·L- 1) and fluorescence imaging were collected for targeting lysosomes in living cells because of lysosomes' acidic microenvironment. The A375 tumor-bearing mice were used to assess the imaging ability of Zn5 in vivo. Mouse tumor xenografts were established by injection of A375 cells with 2×106 cells per flank. Probe (1 μg·g-1) was administered to mice by injection. Images were obtained using IVIS Spectrum CT Imaging System. RESULTS There is a 11-fold intensity increasing as the pH values changing from 8 to 2. The almost unchanged emission intensities suggest Zn5 is stable in both BSA and serum. Zn5 has negligible cytotoxicity for HeLa, 293T and CHO-K1 cells. Zn5 can selectively display lysosomes in living cells. Both the 2D and 3D images in vivo distinguish the tumor from other tissues with good fluorescence contrast. CONCLUSION The high chemical stability, emission in the Vis/NIR range, pH sensitivity, a pKa located in the tumor pH range, and low toxicity make Zn5 is suitable for application as a pH- sensitive fluorescent probe for bio-imaging.
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Aptamers are single-stranded oligonucleotides ( DNA or RNA ) selected through a technology termed "Systematic evolution of ligands by exponential enrichment" ( SELEX ) . In addition to high affinity and high specificity for their target molecules, aptamers have some advantages such as low molecular weight, easy synthesis, high chemical stability, low immunogenicity, and convenient modification. Based on the Cell-SELEX technique, a panel of aptamers which can specifically recognize target cell lines has been generated. By targeting specific membrane proteins in their native state, these aptamers can identify subtle molecular differences among different cell lines, thus have attracted a broad interest in biomedical research. In this review, we summarized the development of aptamers and their use in detection, profiling and imaging of tumor cells. Also, their perspectives were discussed.
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Objective To synthesize a quantum dot (QD) to recognize glioma cells for imaging and photodynamic therapy. Methods By one-pot aqueous approach, near infrared-emitting CdTe was produced. After detection of its physicochemical characterizations, RGD was conjugated. Emission images were observed with confocal microscopy. To test its toxicity, CdTe-RGD with various concentrations was separately added into U251 and 3T3 cells for incubation in dark circulation. To test its photodynamic effect, U251 and 3T3 cells were then irradiated for 5 ~ 60 min using 632.8 nm laser. Results The QD (Φ = 3.75 nm, PL peak wavelength =700 nm, PLQY=20%) achieved was a spherical crystal with excellent monodispersity. Under confocal microscope , U251 cells were visualized but 3T3 cells not. In dark circulation, the survival rates of both U251 and 3T3 cells were above 85%. After laser irradiation, the survival rate of U251 cells decreased to (37 ± 1.6)%with the increasing of irradiation time and CdTe-RGD concentration. Conclusion With good physicochemical characterization and low toxicity, CdTe-RGD could be applied in biomedical imaging and photodynamic therapy of gliomas.
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The aim of this study was to examine the therapeutic potential of sulfasalazine and prednisolone in a mouse collagen antibody-induced arthritis (CAIA) model. Twenty-five male BALB/c mice were randomly divided into five groups: group 1 (G1): control, group 2 (G2): probe control, group 3 (G3): CAIA, group 4 (G4): CAIA+sulfasalazine (10 mg/kg, oral), and group 5 (G5): CAIA+prednisolone (100 mg/kg, oral). Fluorescence bioimaging was performed in vivo 24 and 48 h after treatment with a fluorescence probe (OsteoSense® 680 EX), and all mice were sacrificed. The hind knee joints were fixed in 10% neutral phosphate-buffered formalin, and micro-computed tomography (micro-CT) and histopathological analyses were performed. The paw thickness increased in a time-dependent manner in G3 mice, but trended toward a decrease in both G4 and G5 mice. Fluorescence intensity increased in G3 mice at 24 and 48 h after fluorescence probe treatment, but the fluorescence intensity in G4 and G5 mice was lower than that in G3. Micro-CT analyses showed that the joint surfaces of G3 mice had a rough and irregular articular appearance, but the occurrence of these irregularities was lower in G4 and G5. Hematoxylin and eosin and Safranin O-fast green staining confirmed that destruction of the cartilage and bony structures, synovial hyperplasia, and inflammatory cell infiltration all occurred in G3, and that the occurrence of these phenomena was lower in G4 and G5 than in G3. Taken together, these results suggest that sulfasalazine and prednisolone can reduce acute rheumatoid arthritis in mice.
Subject(s)
Animals , Humans , Male , Mice , Arthritis , Arthritis, Rheumatoid , Cartilage , Collagen , Eosine Yellowish-(YS) , Fluorescence , Formaldehyde , Hematoxylin , Hyperplasia , Joints , Knee Joint , Prednisolone , SulfasalazineABSTRACT
Molecular imaging is a bioimaging that can detect biochemically and genetically relevant events in molecular level in cells and tissues via quantitative imaging signal. Molecular imaging provides potential advantages to examine early diagnosis of specific diseases, to screen new candidates of a drug, to monitor therapeutic effects in real time, and to communicate with both diagnosis and therapeutics. These diverse advantages of molecular imaging can be allowed by development of nanoplatform technology. The nanoplatform-based probes for molecular imaging is widely investigated to grant multimodal molecular imaging and drug delivery together with medical imagings, which includes the issues of biocompatibility, targeting moiety, proteasespecific peptide substrate, quenching/dequenching system etc. In this paper, nanoplatformbased probes are reviewed in aspects of cancer targeting for diagnosis and therapy and multimodal molecular imaging with inorganic/organic hybrid nanoparticles.
Subject(s)
Chimera , Early Diagnosis , Financing, Organized , Molecular Imaging , Nanoparticles , Organothiophosphorus CompoundsABSTRACT
Molecular imaging is a bioimaging that can detect biochemically and genetically relevant events in molecular level in cells and tissues via quantitative imaging signal. Molecular imaging provides potential advantages to examine early diagnosis of specific diseases, to screen new candidates of a drug, to monitor therapeutic effects in real time, and to communicate with both diagnosis and therapeutics. These diverse advantages of molecular imaging can be allowed by development of nanoplatform technology. The nanoplatform-based probes for molecular imaging is widely investigated to grant multimodal molecular imaging and drug delivery together with medical imagings, which includes the issues of biocompatibility, targeting moiety, proteasespecific peptide substrate, quenching/dequenching system etc. In this paper, nanoplatformbased probes are reviewed in aspects of cancer targeting for diagnosis and therapy and multimodal molecular imaging with inorganic/organic hybrid nanoparticles.