A new strategy of using periphyton to simultaneously promote remediation of PAHs-contaminated soil and production of safer crops.

Contaminated farmland leads to serious problems for human health through biomagnification in the soil-crop-human chain. In this paper, we have established a new soil remediation strategy using periphyton for the production of safer rice. Four representative polycyclic aromatic hydrocarbons (PAHs), including phenanthrene (Phe), pyrene (Pyr), benzo[b]fluoranthene (BbF), and benzo[a]pyrene (BaP), were chosen to generate artificially contaminated soil. Pot experiments demonstrated that in comparison with rice cultivation in polluted soil with ΣPAHs (50 mg kg-1) but without periphyton, adding periphyton decreased ΣPAHs contents in both rice roots and shoots by 98.98% and 99.76%, respectively, and soil ΣPAHs removal reached 94.19%. Subsequently, risk assessment of ΣPAHs based on toxic equivalent concentration (TEQ), pollution load index (PLI), hazard index (HI), toxic unit for PAHs mixture (TUm), and incremental lifetime cancer risk (ILCR) indicated that periphyton lowered the ecological and carcinogenicity risks of PAHs. Besides, the role of periphyton in enhancing the rice productivity was revealed. The results indicated that periphyton alleviated the oxidative stress of PAHs on rice by reducing malondialdehyde (MDA) content and increasing total antioxidant capacity (T-AOC). Periphyton reduced the toxic stress of PAHs on the soil by promoting soil carbon cycling and metabolic activities as well. Periphyton also improved the soil's physicochemical properties, such as the percentage of soil aggregate, the contents of humic substances (HSs) and nutrients, which increased rice biomass. These findings confirmed that periphyton could improve rice productivity by enhancing soil quality and health. This study provides a new eco-friendly strategy for soil remediation and simultaneously enables the production of safe crops on contaminated land.

Development of a prognostic scoring system for hepatic vena cava Budd-Chiari syndrome with hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a serious complication of hepatic vena cava Budd-Chiari syndrome (HVC-BCS) that significantly reduces the survival time of patients. Our study aimed to analyze the prognostic factors influencing the survival of HVC-BCS patients with HCC and to develop a prognostic scoring system. METHODS: The clinical and follow-up data of 64 HVC-BCS patients with HCC who received invasive treatment at the First Affiliated Hospital of Zhengzhou University between January 2015 and December 2019 were retrospectively analyzed. Kaplan-Meier curves and log-rank tests were used to analyze the survival curve of patients and the difference in prognoses between the groups. Univariate and multivariate Cox regression analyses were performed to analyze the influence of biochemical, tumor, and etiological characteristics on the total survival time of patients, and a new prognostic scoring system was developed according to the regression coefficients of the independent predictors in the statistical model. The prediction efficiency was evaluated using the time-dependent receiver operating characteristics curve and concordance index. RESULTS: Multivariate analysis showed that serum albumin level < 34 g/L [hazard ratio (HR) = 4.207, 95% confidence interval (CI): 1.816-8.932, P = 0.001], maximum tumor diameter > 7 cm (HR = 3.612, 95% CI: 1.646-7.928, P = 0.001), and inferior vena cava stenosis (HR = 8.623, 95% CI: 3.771-19.715, P < 0.001) were independent predictors of survival. A prognostic scoring system was developed according to the above-mentioned independent predictors, and patients were classified into grades A, B, C and D. Significant differences in survival were found among the four groups. CONCLUSIONS: This study successfully developed a prognostic scoring system for HVC-BCS patients with HCC, which is helpful for clinical evaluation of patient prognosis.