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OBJECTIVE@#Tissue uptake and distribution of nano-/microplastics was studied at a single high dose by gavage in vivo.@*METHODS@#Fluorescent microspheres (100 nm, 3 μm, and 10 μm) were given once at a dose of 200 mg/(kg∙body weight). The fluorescence intensity (FI) in observed organs was measured using the IVIS Spectrum at 0.5, 1, 2, and 4 h after administration. Histopathology was performed to corroborate these findings.@*RESULTS@#In the 100 nm group, the FI of the stomach and small intestine were highest at 0.5 h, and the FI of the large intestine, excrement, lung, kidney, liver, and skeletal muscles were highest at 4 h compared with the control group ( P < 0.05). In the 3 μm group, the FI only increased in the lung at 2 h ( P < 0.05). In the 10 μm group, the FI increased in the large intestine and excrement at 2 h, and in the kidney at 4 h ( P < 0.05). The presence of nano-/microplastics in tissues was further verified by histopathology. The peak time of nanoplastic absorption in blood was confirmed.@*CONCLUSION@#Nanoplastics translocated rapidly to observed organs/tissues through blood circulation; however, only small amounts of MPs could penetrate the organs.
Subject(s)
Microplastics , Plastics , Liver , Microspheres , Lung , Water Pollutants, ChemicalABSTRACT
Objective:To design a kind of head holder for small animal imaging without artifact. Methods: The head holder was designed for small animal imaging according to rodent head stereotaxic apparatus with lightweight and easy molding material (polymethyl methacrylate). The holder can be easily made with ordinary lathe and can be easily operated in small animal imaging device. Results:After the trial in small animal PET-CT, the holder can effectively solve the problems in small animal imaging such as the artifact caused by tiny displacement, tilt head position, deviating from the central field of view and respiratory depression. Conclusion: The small animal imaging device was designed in simple structure to overcome the shortcomings of the existing technology. The operation of the device is simple, which is worthy of popularization head holder of application.
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OBJECTIVE:To observe the distribution of fluorescent material in the respiratory tract of animals with the use of small animal imaging technology to quickly evaluate the effects of respiratory drug delivery. METHODS: The Kunming mice in the experimental group were administered with Cy5.5 fluorescent-labeled aerosol,meanwhile,a positive control group was set up by injecting same amount of compound anhydrous diethyl ether solution via tracheal incubation,with negative control group inhaled the same amount of non-Cy5.5 fluorescently-labeled aerosol. The fluorescent distribution of the aerosolized particles in the respiratory tract was observed. RESULTS: Fluorescently-labeled aerosol was observed in both the experimental group and the positive control group but not in negative control group. CONCLUSION: The small animal imaging technology is expected to be used as a rapid and effective method for evaluating the efficacy of respiratory drug delivery.
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Small animal models are extensively utilized in the study of biomedical sciences. Current animal experiments and analysis are largely restricted to in vitro measurements and need to sacrifice animals to perform tissue or molecular analysis. This prevents researchers from observing in vivo the natural evolution of the process under study. Imaging techniques can provide repeatedly in vivo anatomic and molecular information noninvasively. Small animal imaging systems have been developed to assess biological process in experimental animals and increasingly employed in the field of molecular imaging studies. This review outlines the current developments in nuclear medicine imaging instrumentations including fused multi-modality imaging systems for small animal imaging.