Ultrasonic Heating Detects Lipiodol Deposition within Liver Tumors after Transarterial Embolization: An In Vivo Approach

Computed tomography (CT) is the standard method to evaluate Lipiodol deposition after transarterial embolization (TAE) for a long period. However, iodine but not Lipiodol can be observed on CT. A minimally invasive other method to detect Lipiodol has been needed to evaluate accurate evaluation after procedure. The purpose of this study was to evaluate the efficacy of using the rate of change in sound velocity caused by ultrasonic heating to reflect Lipiodol accumulation after TAE in a rat liver tumor model. We analyzed the association of this developed technique with CT images and histological findings. Eight rats bearing N1S1 cells were prepared. After confirmation of tumor development in a rat liver, Lipiodol was injected via the hepatic artery. Seven days after TAE, CT scan and sound velocity changes caused by ultrasonic heating were measured, and then the rats were sacrificed. An ultrasonic pulse-echo method was used to measure the sound velocity. The temperature coefficient of the sound velocity in each treated tumor was evaluated and compared with the mean CT value and the histological Lipiodol accumulation ratio. Pearson’s correlation coefficients were calculated to assess the correlation between the measured values. The correlation coefficient (r) of the mean CT value and histological Lipiodol accumulation ratio was 0.835 (p = 0.010), which was considered statistically significant. Also, those of the temperature coefficient of the sound velocity and the histological Lipiodol accumulation ratio were statistically significant (r = 0.804; p = 0.016). To our knowledge, this is the first study that reported the efficacy of ultrasonic heating to detect Lipiodol accumulation in rat liver tumors after TAE. Our results suggest that the rate of change in sound velocity caused by ultrasonic heating can be used to evaluate Lipiodol accumulation in liver tumors after TAE, and thus could represent an alternative to CT in this application. This new innovative technique is easy to treat and less invasive in terms of avoiding radiation compared with CT.

Study of the Effect of Chemical Pollution with Coal-Fired Power Plant on the Fish of Lake Kenon (Trans-Baikal Territory, Russia)

In this study, contamination of potentially toxic elements (Cr, Mn, Cu, Zn, Hg and Pb) and species dominant in the fish community of Lake Kenon – Carassius auratus gibelio (Bloch 1782) and Perca fluviatilis (Linnaeus 1758) – were investigated. Chemical elements in samples were determined by atomic emission spectrometry (iCAP-6500, Thermo Scientific, USA) and mass spectrometry (X-7, Thermo Elemental, USA). It was reported that water in Lake Kenon contained low concentrations of the studied metals. The bottom sediments are enriched with Mn, Zn, Hg and Pb. Bioaccumulation factors of chemical elements accumulated from the surrounding water for P. fluviatus and C. auratus gibelio in descending order are as follows: Zn > Pb > Hg > Cu. P. fluviatus accumulates Hg in equal measure from both water and bottom sediments. Manganese and mercury are accumulated in the muscles of C. auratus gibelio from bottom sediments. The high accumulation ratio of Zn and Hg in C. auratus gibelio was obtained from Chara sp. (24 times) and Chironomus spp. (38 times), respectively. High accumulation ratio of Zn (26 times) and Hg (29 times) in P. fluviatus was obtained from amphipods. At the same time, Hg in P. fluviatus muscles was accumulated at high level from Chironomus spp. (67 times). In this way, management decisions for mitigation practices in Lake Kenon should be focussed on for the disposal of wastewater from the ash dump contaminated with chemical elements.

NI-09 Amide Proton Transfer (APT) image is useful for diagnostic imaging of glioma

Introduction: APT image(APT),which images the concentration of amide groups that increases in tumors, is expected to be applied clinically in diagnostic imaging of glioma. Purpose: APT was compared with MET-PET based on the pathological diagnosis results, and it was retrospectively verified that APT was useful for diagnostic imaging of glioma. Methods: A total of 46cases with glioma (WHO 2016 Grade: GII/III/IV) and Pseudoprogression were included. APT measured the APT measurement value by placing the region of interest in the tumor part. MET-PET was administered with 370MBq and the accumulation ratio(TNR) between the tumor part and the normal part was measured. Results: The APT measurement value in all cases was 2.22±1.01 and the TNR was 2.58±1.50,and a correlation was observed between the APT measurement value and the TNR(r=0.6, p<0.001).When the accuracy of discrimination between GII/III/IV (32cases) and Pseudoprogression(14cases) by APT measurement was verified, the sensitivity was 91% and the specificity was 100% at the threshold of 1.81. In the verification of malignancy diagnosis, the measured APT value of GII (6cases) was 2.18±0.43,the measured APT value of GIII (11cases) was 2.67±0.69,and the measured APT value of GIV (15cases) was 2.99±0.61.The measured value showed a significant difference. The measured APT value in the oligodendroglioma group (GII/III:10cases) was 2.37±0.66,the TNR was 3.52±1.41,and the measured APT value in the astrocytoma group (GII/III: 7cases)Was 2.67±0.45 and TNR was 2.41±0.87.In the oligodendroglioma group, the measured APT value was lower and the TNR was higher than in the astrocytoma group. Conclusion: It was suggested that APT may have the same diagnostic ability as MET-PET in diagnosing malignant tumors and distinguishing between recurrence and Pseudoprogression. Patients with an actual APT of 1.81 or higher should consider treatment strategies, and follow-up may be an option for patients with an APT of <1.81.APT,which is not affected by the blood-brain barrier, has little variation in measured values and is considered to be useful for diagnostic imaging of glioma.

Accumulation and Elimination of Tetrodotoxin in the Pufferfish Takifugu obscurus by Dietary Administration of the Wild Toxic Gastropod Nassarius semiplicata

To investigate pufferfish accumulation, elimination, and distribution of tetrodotoxin (TTX), Takifugu obscurus was fed with wild TTX-containing gastropod Nassarius semiplicata to simulate the natural food chain. Three-month-old non-poisonous T. obscurus was fed with wild toxic N. semiplicata at three exposure dose for 28 days, and later, with toxin-free food until day 67. Three fish individuals from each treatment were sampled, and the distribution of TTX in different tissues was measured. The results showed that the accumulation ratio of TTX in the three exposure dose groups ranged from 35.76% to 40.20%. The accumulation ratio in the skin and liver was the highest amongst all tissues, accounting for more than 85% of the total TTX, whereas that in the kidney and gallbladder was the lowest (0.11–0.78%). Studies on the kinetic of TTX accumulation and elimination revealed that the skin was the tissue with the highest accumulation speed constant (8.06), while the liver, kidney, and intestinal tract showed the highest speed of TTX elimination. The time required for TTX reduction to reach the safety limit could be predicted by using standard elimination equations. Qualitative analysis by UPLC-MS/MS revealed the occurrence of seven TTX derivatives in T. obscurus; of these TTX, 5-deoxy TTX, 11-deoxy TTX, 4,9-anhydro TTX were found in all tested tissues.