Synthetic ratiometric fluorescent probes for detection of ions.

Metal cations and anions are essential for versatile physiological processes. Dysregulation of specific ion levels in living organisms is known to have an adverse effect on normal biological events. Owing to the pathophysiological significance of ions, sensitive and selective methods to detect these species in biological systems are in high demand. Because they can be used in methods for precise and quantitative analysis of ions, organic dye-based ratiometric fluorescent probes have been extensively explored in recent years. In this review, recent advances (2015-2019) made in the development and biological applications of synthetic ratiometric fluorescent probes are described. Particular emphasis is given to organic dye-based ratiometric fluorescent probes that are designed to detect biologically important and relevant ions in cells and living organisms. Also, the fundamental principles associated with the design of ratiometric fluorescent probes and perspectives about how to expand their biological applications are discussed.

Differential Chest Computed Tomography Findings of Pulmonary Parasite Infestation Between the Paragonimiasis and Nonparagonimiatic Parasite Infestation.

OBJECTIVE: The aims of this study were to evaluate the chest computed tomography findings of parasite infestation regardless of pathogen and to compare the differential findings between paragonimiasis and nonparagonimiatic parasite infestation (NPPI). METHODS: Between January 2008 and November 2011, 75 patients (46 men; 52.9 ± 14.1 years) with serologically proven parasite infestation and available chest computed tomography images were evaluated. Computed tomography images of 40 patients with paragonimiasis and 35 patients with NPPI (13 with sparganosis, 12 with toxocariasis, 8 with cysticercosis, and 2 with clonorchiasis) were assessed for the presence or absence of pleural abnormalities, consolidation, cavitary lesions, aggregated cysts, worm-migration tracts, and pure ground-glass opacity. Findings associated with consolidation were further assessed for characteristics including size, perilesional ground-glass opacity, presence of perilesional centrilobular nodules, and internal low attenuation, and multisegmentality and bilaterality were assessed for all patients. RESULTS: In both groups, the most common pleural abnormality was pleural effusion (42.5% in paragonimiasis vs 22.9% in NPPI, P = 0.09), and the most common pulmonary abnormality was consolidation (82.5% vs 80.0%, P = 1.00). Multisegmentality (35% vs 42.9%, P = 0.64) and bilaterality (55.0% vs 60%, P = 0.82) of pleuropulmonary lesions were often observed in both groups. Internal low attenuation, perilesional centrilobular nodules, cavitary lesions, and worm-migration tracts were more frequently found in the paragonimiasis group (P ≤ 0.05). CONCLUSIONS: The presence of internal low attenuation and perilesional centrilobular nodules associated with pulmonary consolidative lesions, along with cavitary lesions and worm-migration tracts, is more frequent in patients with paragonimiasis than in patients with NPPI.

Impact of respiratory motion on liver stiffness measurements according to different shear wave elastography techniques and region of interest methods: a phantom study.

PURPOSE: This study quantified the impact of respiratory motion on liver stiffness measurements according to different shear wave elastography (SWE) techniques and region of interest (ROI) methods, using liver fibrosis phantoms. METHODS: Three operators measured stiffness values in four phantoms with different stiffness on a moving platform with two SWE techniques (point-SWE [pSWE] and 2-dimensional SWE [2D-SWE]), three types of motion (static mode and moving mode at low and high speeds), and four ROI methods in 2D-SWE (circle, point, box, and multiple). The circular ROI method was used to compare the two SWE techniques. The occurrence of technical failure and unreliable measurements, stiffness values, and measurement time were evaluated. RESULTS: Technical failure was observed only in moving mode for pSWE and 2D-SWE (n=1 for both). Unreliable measurements were also only observed in moving mode and were significantly less common in 2D-SWE (n=1) than in pSWE (n=12) (P<0.001). No statistically significant differences in the technical failure rate or stiffness values were noted between the static and moving modes for both SWE techniques. The technical failure and unreliable measurement rates were not significantly different among the ROI methods for 2D-SWE. Stiffness values did not differ significantly according to the ROI method used in any moving mode. However, the multiple ROI method had significantly shorter measurement times than the circular ROI method for all moving modes. CONCLUSION: 2D-SWE may be preferable for evaluating liver fibrosis in patients with poor breath-hold. Furthermore, 2D-SWE with multiple ROIs enables rapid measurements, without affecting liver stiffness values.