Short-term PET-derived kinetic estimation for the diagnosis of hepatocellular carcinoma: a combination of the maximum-slope method and dual-input three-compartment model.

BACKGROUND: Kinetic estimation provides fitted parameters related to blood flow perfusion and fluorine-18-fluorodeoxyglucose (18F-FDG) transport and intracellular metabolism to characterize hepatocellular carcinoma (HCC) but usually requires 60 min or more for dynamic PET, which is time-consuming and impractical in a busy clinical setting and has poor patient tolerance. METHODS: This study preliminarily evaluated the equivalence of liver kinetic estimation between short-term (5-min dynamic data supplemented with 1-min static data at 60 min postinjection) and fully 60-min dynamic protocols and whether short-term 18F-FDG PET-derived kinetic parameters using a three-compartment model can be used to discriminate HCC from the background liver tissue. Then, we proposed a combined model, a combination of the maximum-slope method and a three-compartment model, to improve kinetic estimation. RESULTS: There is a strong correlation between the kinetic parameters K1 ~ k3, HPI and [Formula: see text] in the short-term and fully dynamic protocols. With the three-compartment model, HCCs were found to have higher k2, HPI and k3 values than background liver tissues, while K1, k4 and [Formula: see text] values were not significantly different between HCCs and background liver tissues. With the combined model, HCCs were found to have higher HPI, K1 and k2, k3 and [Formula: see text] values than background liver tissues; however, the k4 value was not significantly different between HCCs and the background liver tissues. CONCLUSIONS: Short-term PET is closely equivalent to fully dynamic PET for liver kinetic estimation. Short-term PET-derived kinetic parameters can be used to distinguish HCC from background liver tissue, and the combined model improves the kinetic estimation. CLINICAL RELEVANCE STATEMENT: Short-term PET could be used for hepatic kinetic parameter estimation. The combined model could improve the estimation of liver kinetic parameters.

Feasibility of perfusion and early-uptake 18F-FDG PET/CT in primary hepatocellular carcinoma: a dual-input dual-compartment uptake model.

PURPOSE: PET enables a concurrent evaluation of perfusion status and metabolic activity. We aimed to evaluate the feasibility of perfusion and early-uptake 18F-FDG PET/CT in hepatocellular carcinoma (HCC) using a dual-input dual-compartment uptake model. MATERIALS AND METHODS: Data from 5 min dynamic PET/CT and conventional PET/CT scans were retrospectively collected from 17 pathologically diagnosed HCCs. Parameters such as hepatic arterial blood flow (Fa), portal vein blood flow (Fv), total blood flow (F), hepatic arterial perfusion index (HPI), portal vein perfusion index (PPI), blood volume (BV), extracellular mean transit time (MTT) and intracellular uptake rate (Ki) were calculated. Fa, HPI, MTT and Ki images were generated and used to identify HCC. RESULTS: Compared with the surrounding liver tissue, HCCs showed significant increases in Fa, HPI, Ki and the maximum standard uptake value (SUVmax) (all P < 0.001) and significant reductions in Fv (P < 0.05) and PPI (P < 0.001). F, BV and MTT (all P > 0.05) did not differ significantly between HCCs and the surrounding liver tissue. Perfusion and early-uptake PET/CT increased the positivity rate of HCCs from 52.9% with conventional PET/CT alone to 88.2% with the combined method (P < 0.05). CONCLUSIONS: Perfusion and early-uptake PET/CT are feasible for diagnosing HCC and provide added functional information to enhance diagnostic performance.

A PVA/LiCl/PEO interpenetrating composite electrolyte with a three-dimensional dual-network for all-solid-state flexible aluminum-air batteries.

Aluminum-air batteries are promising electronic power sources because of their low cost and high energy density. However, traditional aluminum-air batteries are greatly restricted from being used in the field of flexible electronics due to the rigid battery structure, and the irreversible corrosion of the anode by the alkaline electrolyte, which greatly reduces the battery life. To address these issues, a three-dimensional dual-network interpenetrating structure PVA/LiCl/PEO composite gel polymer electrolyte (GPE) is proposed. The gel polymer electrolyte exhibits good flexibility and high ionic conductivity (σ = 6.51 × 10-3 S cm-1) at room temperature. Meanwhile, benefiting from the high-performance GPE, an assembled aluminum-air coin cell shows a highest discharge voltage of 0.73 V and a peak power density (P max) of 3.31 mW cm-2. The Al specific capacity is as high as 735.2 mA h g-1. A flexible aluminum-air battery assembled using the GPE also performed stably in flat, bent, and folded states. This paper provides a cost-effective and feasible way to fabricate a composite gel polymer electrolyte with high performance for use in flexible aluminum-air batteries, suitable for a variety of energy-related devices.

[Monthly deworming in dogs for echinococcosis control in two counties of Xinjiang Uygur Autonomous Region].

OBJECTIVE: To verify the application and effectiveness of monthly deworming for all dogs in the control of Echinococcus granulosus infection. METHODS: Baited praziquantel was used to treat all registered dogs monthly by hydatid disease control officers at village level and all stray (unowned) dogs were eliminated in the counties of Hutubi and Wensu in 1987-1990 and 1990-1994 respectively. Prevalence of echinococcosis in dogs and sheep was recorded yearly. RESULTS: The infection rate in dogs decreased from 18.5% and 14.7% before implementation of the control measure to zero in 3-4 years in Hutubi and Wensu Counties respectively. Prevalence of hydatid disease in new born sheep was reduced by more than 85% in comparison to the same age sheep before the control program in both counties. CONCLUSION: "Monthly drug administration to all dogs" is an effective way to the control of echinococcosis in dogs and of hydatid disease in sheep.