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Purpose: The purpose of this study was to determine if CT and MRI features can accurately differentiate mucinous cystic neoplasms (MCNs) from simple liver cysts and to compare accuracy of CT and MRI in detecting these features., Methods: Eighty-four surgically treated lesions with pre-operative CT or MRI were evaluated by two abdominal radiologists for upstream biliary dilatation, perfusional change, internal hemorrhage, thin septations, thick septations/nodularity, lobar location, and number of coexistent liver cysts. Odds ratios, sensitivities, specificities, and positive and negative predictive values were calculated for association of each feature with MCNs., Results: Of 84 liver lesions, 13 (15%) were MCNs, all in women, and 71 (85%) were simple cysts, in 59 women and 12 men. Thick septations/nodularity, upstream biliary dilation, thin septations, internal hemorrhage, perfusional change, and fewer than 3 coexistent liver cysts were more frequent in MCNs than in simple cysts. The combination of thick septations/nodularity and at least one additional associated feature showed high specificity for MCNs (94-98%). MRI detected significant associations of biliary dilation, thin septations, and hemorrhage/debris with MCNs which CT did not., Conclusion: Surgically treated MCNs of the liver with preoperative imaging occurred at our institution only in women. Thick septations or nodularity, biliary dilation, thin septations, internal hemorrhage or debris, perfusional change, and fewer than 3 coexistent liver cysts are features that help differentiate MCNs from simple cysts. MRI has advantages over CT in detecting these features., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Novel citric acid based photoluminescent dyes and biodegradable polymers are synthesized via a facile "one-pot" reaction. A comprehensive understanding of the fluorescence mechanisms of the resulting citric acid-based fluorophores is reported. Two distinct types of fluorophores are identified: a thiozolopyridine family with high quantum yield, long lifetime, and exceptional photostability, and a dioxopyridine family with relatively lower quantum yield, multiple lifetimes, and solvent-dependent band shifting behavior. Applications in molecular labeling and cell imaging were demonstrated. The above discoveries contribute to the field of fluorescence chemistry and have laid a solid foundation for further development of new fluorophores and materials that show promise in a diversity of fluorescence-based applications., Statement of Significance: Photoluminescent materials are pivotal for fluorescence based imaging, labeling and sensing applications. Understanding their fluorescence mechanism is challenging and imperative. We develop a new class of citric acid-derived fluorescent materials in forms of polymers and small molecular dyes by a one-step solvent free reaction. We discovered two different classes of citric acid-derived fluorophores. A two-ring thiozolopyridine structure demonstrates strong fluorescence and exceptional resistance to photo-bleaching. A one-ring dioxopyridine exhibits relative weak fluorescence but with intriguing excitation and solvent-dependent emission wavelength shifting. Our methodology of synthesizing citric acid-derived fluorophores and the understanding on their luminescence are instrumental to the design and production of a large number of new photoluminescent materials for biological and biomedical applications., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)