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ABSTRACT The newly discovered complete ammonia-oxidizing (comammox) Nitrospira has been identified in different environments, including coastal environments, where salinity is one of the most important factors for the abundance and activity of nitrifiers. Here, we demonstrate the effect of salinity on comammox Nitrospira, canonical ammonia-oxidizing bacteria (AOB), and ammonia-oxidizing archaea (AOA) in the intertidal sediments of the Yangtze River estuary based on microcosm experiments, DNA stable-isotope probing (DNA-SIP), and potential ammonium-oxidation rate (PAR) tests for different groups of ammonia oxidizers with selective inhibitors. During microcosm incubations, the abundance of comammox Nitrospira was more sensitive to increased salinity than that of other ammonia oxidizers. The results obtained with DNA-SIP heavy fractions showed that the dominant phylotype in clade A.2 (containing genes involved in the adaptation to haloalkaline environments) had high proportions in comammox Nitrospira community under both freshwater (0.06% salinity) and highly saline water (3% salinity) conditions. In contrast, another phylotype of clade A.2 (which lacks these genes) was dominant only under freshwater conditions. The PARs confirmed that comammox Nitrospira presented greater contributions to nitrification under freshwater conditions with a PAR of 4.37 ± 0.53 mg N·day–1·kg soil–1 (54%) than under saline water conditions with a PAR of 0.60 ± 0.94 mg N·day–1·kg soil–1 (18%). Moreover, AOA were specific to saline water conditions, whereas AOB were common under both freshwater and saline water conditions (44% and 52%, respectively). The present study provided evidence that salinity markedly affects the activity of comammox Nitrospira, and that the salt sensitivity of different phylotypes varies. IMPORTANCE Complete ammonia oxidation (comammox) is a newly discovered type of nitrification through which ammonia is oxidized to nitrate in an organism. Comammox Nitrospira were abundantly found in coastal ecosystems and demonstrated high community diversity. Changes in salinity are considered one of the most important factors to comammox Nitrospira in coastal ecosystems; however, reports on the correlation between them remain inconsistent. Therefore, it is critical to experimentally determine the influence of salinity on comammox Nitrospira in the coastal ecosystem. This study demonstrated a clear effect of salinity on the abundance, activity, and relative contribution of different ammonia oxidizers, especially for comammox Nitrospira. To the best of our knowledge, this is the first study demonstrating comammox Nitrospira activity at seawater salinities, implying the existence of a salt-tolerant type comammox Nitrospira, despite its activity being much lower than in freshwater conditions. The indicated correlation between the activity of specific comammox Nitrospira and salinity is anticipated to provide insights into the distribution of comammox Nitrospira and their potential contributions in estuaries and coastal ecosystems.

Abstract Objective Post-hepatectomy liver failure (PHLF) is a severe complication in patients with hepatocellular carcinoma (HCC) who underwent hepatectomy. This study aims to develop a nomogram of PHLF grade B–C in patients with huge HCC (diameter ≥ 10 cm). Methods We retrospectively collected clinical information of 514 and 97 patients who underwent hepatectomy for huge HCC at two medical centers between 2016 and 2021. Univariate and multivariate analysis were carried out to screen the independent risk factors of PHLF grade B–C, which were visualized as a nomogram. Results Three Hundred Forty Three Thousand One Hundred Seventy One and 97 HCC patients were included in the training cohort, internal validation cohort, and external validation cohort, with probabilities of PHLF grade B–C of 15.1%, 12.9%, and 22.7%, respectively. Pre-operative modified albumin-bilirubin (mALBI) grade (p

PurposeWe aimed to investigate the feasibility of lenvatinib plus anti-PD-1 therapy as a conversion therapy for initially unresectable hepatocellular carcinoma (HCC).MethodsPatients with initially unresectable HCC who received combined lenvatinib and anti-PD-1 antibody between May 2020 and Jan 2022 in Zhongshan Hospital were retrospectively analyzed. Tumor response and resectability were assessed by imaging every two months according to RECIST version 1.1 and modified RECIST (mRECIST) criteria.ResultsA total of 107 patients were enrolled. 30 (28%) of them received conversion surgery within 90.5 (range: 53–456) days after the initiation of lenvatinib plus anti-PD-1 therapy. At baseline, the median largest tumor diameter of these 30 patients was 9.2 cm (range: 3.5-15.0 cm), 26 patients had Barcelona Clinic Liver Cancer stage B-C, and 4 had stage A. Prior to surgery, all cases displayed tumor regression and 15 patients achieved objective response. Pathological complete response (pCR) was observed in 10 patients. No severe drug-related adverse events or surgical complications were observed. After a median follow-up of 16.5 months, 28 patients survived and 11 developed tumor recurrence. Survival analysis showed patients achieving tumor response before surgery or pCR had a longer tumor-free survival. Notably, patients with microvascular invasion (MVI) had significantly higher recurrence rate and poorer overall survival than patients without.ConclusionsLenvatinib combined with anti-PD-1 therapy represents a feasible conversion strategy for patients with initially unresectable HCC. Patients achieving tumor responses are more likely to benefit from conversion resection to access a longer term of tumor-free survival.

Abstract Genotoxicity refers to the ability of harmful substances to damage genetic information in cells. Being exposed to chemical and biological agents can result in genomic instabilities and/or epigenetic alterations, which translate into a variety of diseases, cancer included. This concise review discusses, from both a genetic and epigenetic point of view, the current detection methods of different agents’ genotoxicity, along with their basic and clinical relation to human cancer, chemotherapy, germ cells and stem cells.

In order to study the corrosion behavior of a new type of 439 ferritic stainless steel in marine atmospheric environment,439 stainless steel samples were put into two test stations in typical marine atmospheric environment (Wenchang test station and Qingdao test station) and one inland urban atmospheric environment (Wuhan test station) for atmospheric exposure test.After two years of exposure,the samples were tested by electrochemical test and analyzed by ultra depth of field microscope,scanning electron microscope (SEM) and energy dispersive spectrometer (EDS).Results showed that the main corrosion form of 439 stainless steel in atmospheric environment was pitting corrosion,and the corrosion degree in Wenchang area was the highest.Meanwhile,the corrosion products were mainly composed of iron oxides,and the samples still had passivation ability in 3.5% (mass fraction) NaCl solution after exposure.The electrochemical test results were consistent with the macro and micro morphology judgment results,i.e.,the samples in Wenchang area corroded most seriously and had the lowest corrosion potential,revealing that the stability of the passive film on those samples was the worst.The samples in Qingdao test station also corroded seriously,while those in Wuhan test station had the lowest corrosion degree.

In order to study the initial soil corrosion behavior of Q235 steel and hot-dip galvanized steel， which are commonly used metallic materials for grounding grid equipment， in a brown loam soil environment， four soil corrosion experimental sites-both inside and outside of Dongjin and Qiaoying stations were chosen in the Xiangyang area of Hubei province.Macro-morphological analysis，micro-morphological analysis，corrosion product analysis and electrochemical testing were employed to analyze the specimens.The morphology analysis results showed that the surface of the carbon steel sample corroded for 1 a in the soil environment of Xiangyang was non-uniform corrosion with obvious pockmarked corrosion pits visible， while the galvanized steel material exhibited no obvious red rust without the obvious damage on the surface galvanized layer.The analysis of corrosion products showed that the brown soil in Xiangyang area was an alkaline soil with high moisture content.The main components of the rust layer on the surface of Q235 steel soil buried sample 1 a were iron oxides and trace amounts of SiO2， while the corrosion products on the surface of galvanized steel were mainly zinc oxides and trace amounts of SiO2.The correlation analysis between corrosion rate and soil physicochemical properties displayed that in the soil environment of Xiangyang， the corrosion rate of the two samples was positively correlated with soil physicochemical properties.Specifically， the soil pH value had the most significant impact on soil corrosion rate.The electrochemical results indicated that the galvanized layer on the surface of galvanized steel provided good protection for the substrate， and the corrosion current density of galvanized steel was 1～2 orders of magnitude lower than that of Q235 steel.Overall， galvanized steel materials exhibited superior corrosion resistance compared to Q235 steel materials in the brown soil environment of Xiangyang region.Notably，the pH of the local soil had a major impact on the galvanized steel material’s rate of corrosion in the soil.