Advancing Lithium-Magnesium Separation: Pioneering Swelling-Embedded Cation Exchange Membranes Based on Sulfonated Poly(ether ether ketone)

With the continuous advancement of electrodialysis (ED) technology, there arises a demand for improved monovalent cation exchange membranes (CEMs). However, limitations in membrane materials and structures have resulted in the low selectivity of monovalent CEMs, posing challenges in the separation of Li+ and Mg2+. In this investigation, a designed CEM with a swelling-embedded structure was created by integrating a polyelectrolyte containing N-oxide Zwitterion into a sulfonated poly(ether ether ketone) (SPEEK) membrane, leveraging the notable solubility characteristic of SPEEK. The membranes were prepared by using N-oxide zwitterionic polyethylenimine (ZPEI) and 1,3,5-benzenetrlcarbonyl trichloride (TMC). The as-prepared membranes underwent systematic characterization and testing, evaluating their structural, physicochemical, electrochemical, and selective ED properties. During ED, the modified membranes demonstrated notable permeability selectivity for Li+ ions in binary (Li+/Mg2+) systems. Notably, at a constant current density of 2.5 mA cm-2, the modified membrane PEI-TMC/SPEEK exhibited significant permeability selectivity ( P Mg 2 + Li + = 5.63 ) in the Li+/Mg2+ system, while ZPEI-TMC/SPEEK outperformed, displaying remarkable permeability selectivity ( P Mg 2 + Li + = 12.43 ) in the Li+/Mg2+ system, surpassing commercial monovalent cation-selective membrane commercial monovalent cation-selective membrane (CIMS). Furthermore, in the Li+/Mg2+ binary system, Li+ flux reached 9.78 × 10-9 mol cm-2 s-1 for ZPEI-TMC/SPEEK, while its Mg2+ flux only reached 2.7 × 10-9 mol cm-2 s-1, showing potential for lithium-magnesium separation. In addition, ZPEI-TMC/SPEEK was tested for performance and stability at high current densities. This work offers a straightforward preparation process and an innovative structural approach, presenting methodological insights for the advancement of lithium and magnesium separation techniques.

Hypoxia-driven tumor stromal remodeling and immunosuppressive microenvironment in scirrhous HCC

BACKGROUND AND AIMS

Scirrhous HCC (SHCC) is one of the unique subtypes of HCC, characterized by abundant fibrous stroma in the tumor microenvironment. However, the molecular traits of SHCC remain unclear, which is essential to develop specialized therapeutic approaches for SHCC.

APPROACH AND RESULTS

We presented an integrative analysis containing single-cell RNA-sequencing, whole-exome sequencing, and bulk RNA-sequencing in SHCC and usual HCC samples from 134 patients to delineate genomic features, transcriptomic profiles, and stromal immune microenvironment of SHCC. Multiplexed immunofluorescence staining, flow cytometry, and functional experiments were performed for validation. Here, we identified SHCC presented with less genomic heterogeneity while possessing a unique transcriptomic profile different from usual HCC. Insulin-like growth factor 2 was significantly upregulated in SHCC tumor cells compared to usual HCC, and could serve as a potential diagnostic biomarker for SHCC. Significant tumor stromal remodeling and hypoxia were observed in SHCC with enrichment of matrix cancer-associated fibroblasts and upregulation of hypoxic pathways. Insulin-like growth factor 2 was identified as a key mediator in shaping the hypoxic stromal microenvironment of SHCC. Under this microenvironment, SHCC exhibited an immunosuppressive niche correlated to enhanced VEGFA signaling activity, where CD4 + T cells and CD8 + T cells were dysfunctional. Furthermore, we found that another hypoxic-related molecule SPP1 from SHCC tumor cells suppressed the function of dendritic cells via the SPP1-CD44 axis, which also probably hindered the activation of T cells.

CONCLUSION

We uncovered the genomic characteristics of SHCC, and revealed a hypoxia-driven tumor stroma remodeling and immunosuppressive microenvironment in SHCC.

A TGF-β-dominant chemoresistant phenotype of hepatoblastoma associated with aflatoxin exposure in children

BACKGROUND AND AIMS

Hepatoblastoma (HB) is the most common liver cancer in children, posing a serious threat to children's health. Chemoresistance is the leading cause of mortality in patients with HB. A more explicit definition of the features of chemotherapy resistance in HB represents a fundamental urgent need.

APPROACH AND RESULTS

We performed an integrative analysis including single-cell RNA sequencing, whole-exome sequencing, and bulk RNA sequencing in 180 HB samples, to reveal genomic features, transcriptomic profiles, and the immune microenvironment of HB. Multicolor immunohistochemistry staining and in vitro experiments were performed for validation. Here, we reported four HB transcriptional subtypes primarily defined by differential expression of transcription factors. Among them, the S2A subtype, characterized by strong expression of progenitor ( MYCN , MIXL1 ) and mesenchymal transcription factors ( TWIST1 , TBX5 ), was defined as a new chemoresistant subtype. The S2A subtype showed increased TGF-β cancer-associated fibroblast and an immunosuppressive microenvironment induced by the upregulated TGF-β of HB. Interestingly, the S2A subtype enriched SBS24 signature and significantly higher serum aflatoxin B1-albumin (AFB1-ALB) level in comparison with other subtypes. Functional assays indicated that aflatoxin promotes HB to upregulate TGF-β. Furthermore, clinical prognostic analysis showed that serum AFB1-ALB is a potential indicator of HB chemoresistance and prognosis.

CONCLUSIONS

Our studies offer new insights into the relationship between aflatoxin and HB chemoresistance and provide important implications for its diagnosis and treatment.

Ion Resource Recovery via Electrodialysis Fabricated with Poly(Arylene Ether Sulfone)-Based Anion Exchange Membrane in Organic Solvent System

Ion resource recovery from organic wastewater is beneficial for achieving emission peaks and carbon neutrality targets. Advanced organic solvent-resistant anion exchange membranes (AEMs) for treating organic wastewater via electrodialysis (ED) are of significant interest. Herein, a kind of 3D network AEM based on poly(arylene ether sulfone) cross-linked with a flexible cross-linker (DBH) for ion resource recovery via ED in organic solvent system is reported. Investigations demonstrate that the as-prepared AEMs show excellent dimensional stability in 60% DMSO (aq.), 60% ethanol (aq.), and 60% acetone (aq.), respectively. For example, the optimized AEM shows very low swelling ratios of 1.04-1.10% in the organic solvents. ED desalination ratio can reach 99.1% after exposure of the AEM to organic solvents for 30 days, and remain > 99% in a mixture solution containing organic solvents and 0.5 m NaCl. Additionally, at a current density of 2.5 mA cm-2, the optimized AEM soaked in organic solvents for 30 days shows a high perm-selectivity (Cl-/SO4 2-) of 133.09 (vs 13.11, Neosepta ACS). The superior ED performance is attributed to the stable continuous sub-nanochannels within AEM confirmed by SAXS, rotational energy barriers, etc. This work shows the potential application of cross-linked AEMs for resource recovery in organic wastewater.

BMI1 Silencing Liposomes Suppress Postradiotherapy Cancer Stemness against Radioresistant Hepatocellular Carcinoma

Radiotherapy causes DNA damage by direct ionization and indirect generation of reactive oxygen species (ROS) thereby destroying cancer cells. However, ionizing radiation (IR) unexpectedly elicits metastasis and invasion of cancer cells by inducing cancer stem cells' (CSCs) properties. As BMI1 is a crucial gene that causes radioresistance and an unfavorable prognosis of hepatocellular carcinoma (HCC), BMI1 inhibitor PTC-209 has been encapsulated in a ROS-responsive liposome (LP(PTC-209)) to be temporally and spatially delivered to radioresistant HCC tissue. The ROS generated during IR was not only considered to directly cause tumor cell death but also be used as a stimulator to trigger ROS-responsive drug release from LP(PTC-209). The PTC-209 released into resistant HCC tissue under radiotherapy further led to cancer stem cell (CSC) differentiation and then recovered radiosensitivity of HCC tumor. The suppression of the radioresistant performance of LP(PTC-209) has been proved on radiosensitive and radioresistant Hepa1-6 CSC tumor models, respectively. Our study clarified the relationship between radiotherapy and cancer stemness and provided insights to achieve complete suppression of radioresistant HCC tumor by inhibiting cancer stemness.

Size-Tunable Nanoregulator-Based Radiofrequency Ablation Suppresses MDSCs and Their Compensatory Immune Evasion in Hepatocellular Carcinoma

Radiofrequency ablation (RFA) is a widely used therapy for hepatocellular carcinoma (HCC). However, in cases of insufficient RFA (iRFA), nonlethal temperatures in the transition zone increase the risk of postoperative relapse. The pathological analysis of HCC tissues shows that iRFA-induced upregulation of myeloid-derived suppressor cells (MDSCs) in residual tumors is critical for postoperative recurrence. Furthermore, this study demonstrates, for the first time, that combining MDSCs suppression strategy during iRFA can unexpectedly lead to a compensatory increase in PD-L1 expression on the residual MDSCs, attributed to relapse due to immune evasion. To address this issue, a novel size-tunable hybrid nano-microliposome is designed to co-deliver MDSCs inhibitors (IPI549) and αPDL1 antibodies (LPIP) for multipathway activation of immune responses. The LPIP is triggered to release immune regulators by the mild heat in the transition zone of iRFA, selectively inhibiting MDSCs and blocking the compensatory upregulation of PD-L1 on surviving MDSCs. The combined strategy of LPIP + iRFA effectively ablates the primary tumor by activating immune responses in the transition zone while suppressing the compensatory immune evasion of surviving MDSCs. This approach avoids the relapse of the residual tumor in a post-iRFA incomplete ablation model and appears to be a promising strategy in RFA for the eradication of HCC.

METTL5-mediated 18S rRNA m6A modification promotes oncogenic mRNA translation and intrahepatic cholangiocarcinoma progression

Intrahepatic cholangiocarcinoma (ICC) is a deadly cancer with rapid tumor progression. While hyperactive mRNA translation caused by mis-regulated mRNA or tRNA modifications promotes ICC development, the role of rRNA modifications remains elusive. Here, we found that 18S rRNA m6A modification and its methyltransferase METTL5 were aberrantly upregulated in ICC and associated with poorer survival (log rank test, p < 0.05). We further revealed the critical role of METTL5-mediated 18S rRNA m6A modification in regulation of ICC cell growth and metastasis using loss- and gain-of function assays in vitro and in vivo. The oncogenic function of METTL5 is corroborated using liver-specific knockout and overexpression ICC mouse models. Mechanistically, METTL5 depletion impairs 18S rRNA m6A modification that hampers ribosome synthesis and inhibits translation of G-quadruplex-containing mRNAs that are enriched in the transforming growth factor (TGF)-β pathway. Our study uncovers the important role of METTL5-mediated 18S rRNA m6A modification in ICC and unravels the mechanism of rRNA m6A modification-mediated oncogenic mRNA translation control.

Comparison of clinical efficacy between LAPS and ALPPS in the treatment of hepatitis B virus-related hepatocellular carcinoma

Background

Insufficient post-operative future liver remnant (FLR) limits the feasibility of hepatectomy for patients. Staged hepatectomy is an effective surgical approach that can improve the resection rate of hepatocellular carcinoma (HCC). This study aimed to compare the safety and efficacy of laparoscopic microwave ablation and portal vein ligation for staged hepatectomy (LAPS) and classical associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in the treatment of hepatitis B virus (HBV)-related HCC.

Methods

Clinical data of patients with HBV-related HCC who underwent LAPS or ALPPS in our institute between January 2017 and May 2022 were retrospectively analysed.

Results

A total of 18 patients with HBV-related HCC were retrospectively analysed and divided into the LAPS group (n = 9) and ALPPS group (n = 9). Eight patients in the LAPS group and eight patients in the ALPPS group proceeded to a similar resection rate (88.9% vs 88.9%, P = 1.000). The patients undergoing LAPS had a lower total comprehensive complication index than those undergoing ALPPS but there was not a significant different between the two groups (8.66 vs 35.87, P = 0.054). The hypertrophy rate of FLR induced by ALPPS tended to be more rapid than that induced by LAPS (24.29 vs 13.17 mL/d, P = 0.095). The 2-year recurrence-free survival (RFS) was 0% for ALPPS and 35.7% for LAPS (P = 0.009), whereas the 2-year overall survival for ALPPS and LAPS was 33.3% and 100.0% (P = 0.052), respectively.

Conclusions

LAPS tended to induce lower morbidity and FLR hypertrophy more slowly than ALPPS, with a comparable resection rate and better long-term RFS in HBV-related HCC patients.

Rechargeable Multifunctional Anti-Bacterial AEMs for Electrodialysis: Improving Anti-Biological Performance via Synergistic Antibacterial Mechanism

Constructing a functional layer on the surface of commercial membrane (as a substrate) to inhibit the formation of biofilms is an efficient strategy to prepare an antibacterial anion exchange membrane (AEM). Herein, a rechargeable multifunctional anti-biological system is reported by utilizing the mussel-inspired L-dopa connection function on commercial AEMs. Cobalt nanoparticles (Co NPs) and N-chloramine compounds are deposited on the AEM surface by a two-step modification procedure. The anti-biofouling abilities of the membranes are qualitatively and quantitatively analyzed by adopting common Gram-negative (E. coli) and Gram-positive (S. aureus & Bacillus) bacteria as model biofouling organisms. The optimized membrane exhibits a high stability concerning the NaCl solution separation performance within 240 min. Meantime, the mechanism of the anti-adhesion is un-veiled at an atomic level and molecular dynamics (MD) simulation are conducted to measure the interaction, adsorption energy and average loading by using lipopolysaccharide (LPS) of E. coli. In view of the superior performance of antibacterial surfaces, it is believed that this work could provide a valuable guideline for the design of membrane materials with resistance to biological contamination.

Identification and validation of a plasma metabolomics-based model for risk stratification of intrahepatic cholangiocarcinoma

BACKGROUND

Liver resection is the mainstay of curative treatment for intrahepatic cholangiocarcinoma (ICC) while the postoperative prognosis varies greatly, with no recognized biomarker. We aimed to identify the plasma metabolomic biomarkers that could be used for preoperative risk stratification of ICC patients.

METHODS

108 eligible ICC patients who underwent radical surgical resection between August 2012 and October 2020 were enrolled. Patients were randomly divided into a discovery cohort (n = 76) and a validation cohort (n = 32) by 7:3. Metabolomics profiling of preoperative plasma was performed and clinical data were collected. The least absolute shrinkage and selection operator (LASSO) regression, Cox regression, and receiver operating characteristic (ROC) analyses were used to screen and validate the survival-related metabolic biomarker panel and construct a LASSO-Cox prediction model.

RESULTS

10 survival-related metabolic biomarkers were used for construction of a LASSO-Cox prediction model. In the discovery and validation cohorts, the LASSO-Cox prediction model achieved an AUC of 0.876 (95%CI: 0.777-0.974) and 0.860 (95%CI: 0.711-1.000) in evaluating 1-year OS of ICC patients, respectively. The OS of ICC patients in the high-risk group was significantly worse than that in the low-risk group (discovery cohort, p < 0.0001; validation cohort: p = 0.041). Also, the LASSO-Cox risk score (HR 2.43, 95%CI: 1.81-3.26, p < 0.0001) was a significant independent risk factor associated with OS.

CONCLUSIONS

The LASSO-Cox prediction model has potential as an important tool in evaluating the OS of ICC patients after surgical resection and can be used as prediction tools to implement the best treatment options that could result in better outcomes.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Predicting Drug Treatment Outcomes in Childrens with Tuberous Sclerosis Complex-Related Epilepsy: A Clinical Radiomics Study

BACKGROUND AND PURPOSE

Highly predictive markers of drug treatment outcomes of tuberous sclerosis complex-related epilepsy are a key unmet clinical need. The objective of this study was to identify meaningful clinical and radiomic predictors of outcomes of epilepsy drug treatment in patients with tuberous sclerosis complex.

MATERIALS AND METHODS

A total of 105 children with tuberous sclerosis complex-related epilepsy were enrolled in this retrospective study. The pretreatment baseline predictors that were used to predict drug treatment outcomes included patient demographic and clinical information, gene data, electroencephalogram data, and radiomic features that were extracted from pretreatment MR imaging scans. The Spearman correlation coefficient and least absolute shrinkage and selection operator were calculated to select the most relevant features for the drug treatment outcome to build a comprehensive model with radiomic and clinical features for clinical application.

RESULTS

Four MR imaging-based radiomic features and 5 key clinical features were selected to predict the drug treatment outcome. Good discriminative performances were achieved in testing cohorts (area under the curve = 0.85, accuracy = 80.0%, sensitivity = 0.75, and specificity = 0.83) for the epilepsy drug treatment outcome. The model of radiomic and clinical features resulted in favorable calibration curves in all cohorts.

CONCLUSIONS

Our results suggested that the radiomic and clinical features model may predict the epilepsy drug treatment outcome. Age of onset, infantile spasms, antiseizure medication numbers, epileptiform discharge in left parieto-occipital area of electroencephalography, and gene mutation type are the key clinical factors to predict the epilepsy drug treatment outcome. The texture and first-order statistic features are the most valuable radiomic features for predicting drug treatment outcomes.

Integrated analysis of long non-coding RNAs and mRNA expression profiles identified potential interactions regulating melanogenesis in chicken skin

1. Long non-coding RNAs (lncRNAs) play important roles in various physiological functions. However, the mechanisms underlying the regulation of lncRNAs in melanogenesis remain unclear. To determine the molecular mechanisms involved in skin melanogenesis, the present study depicted the expression profiles of lncRNAs and messenger RNAs (mRNAs) in black- (B group) and white- (W group) skinned chickens using RNA sequencing.2. In total, 373 differentially expressed lncRNAs (DELs; 203 up-regulated and 170 down-regulated) and 253 differentially expressed genes (DEGs; 152 up-regulated and 101 down-regulated) were identified between the B and W groups. A total of eight known melanogenesis-related genes were identified (KIT, TYRP1, DCT (TYRP2), SLC45A2, OCA2, EDNRB2, TRPM1 and RAB38).3. Functional annotation of the co-expressed DEGs and DELs was performed using Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analyses. The co-expressed DEGs were mainly involved in melanogenesis and the co-expressed genes of 117 and 108 DELs were significantly enriched in the melanogenesis and tyrosine metabolism pathways, respectively.4. The DEL-DEG interaction network revealed that three lncRNAs (XR_003072387.1, XR_003075112.1, and XR_003077033.1) and DCT genes may have key roles in regulating melanogenesis in chicken skin. This data provides the groundwork for studying the lncRNA regulatory mechanisms of skin melanogenesis and suggested a new perspective on the modulation of melanogenesis in chicken skin based on a lncRNA-mRNA causal regulatory network.

METTL1-Mediated m7G tRNA Modification Promotes Lenvatinib Resistance in Hepatocellular Carcinoma

The tyrosine kinase inhibitor lenvatinib is a first-line drug for treating patients with advanced hepatocellular carcinoma (HCC). However, its efficacy is severely hampered by drug resistance. Insights into the molecular mechanisms underlying lenvatinib resistance could provide new strategies to improve and prolong responses. Here, we performed unbiased proteomic screening of parental and lenvatinib-resistant HCC cells and discovered that methyltransferase-like protein-1 (METTL1) and WD repeat domain 4 protein (WDR4), the two key components of the tRNA N7-methylguanosine (m7G) methyltransferase complex, were dramatically upregulated in lenvatinib-resistant cells. METTL1 knockdown overrode resistance by impairing the proliferation capacity of HCC cells and promoting apoptosis under lenvatinib treatment. In addition, overexpression of wild-type METTL1 but not its catalytic dead mutant induced lenvatinib resistance. Animal experiments including hydrodynamic injection, subcutaneous implantation, and orthotopic xenograft mouse models further demonstrated the critical function of METTL1/WDR4-mediated m7G tRNA modification in promoting lenvatinib resistance in vivo. Mechanistically, METTL1 promoted translation of EGFR pathway genes to trigger drug resistance. This work reveals the important role of METTL1-mediated m7G tRNA modification in promoting lenvatinib resistance and provides a promising prediction marker and intervention target for resistance.

SIGNIFICANCE

Upregulation of tRNA m7G methyltransferase complex components METTL1 and WDR4 promotes lenvatinib resistance in HCC and confers a sensitivity to METTL1 targeting, providing a promising strategy to override resistance.

[Application of robot-assisted laparoscopic sentinel lymph node tracing in treating endometrial carcinoma]

Objective: To investigate the value of robot-assisted laparoscopic indocyanine green sentinel lymph node (SLN) tracing in treating endometrial carcinoma. Methods: Thirty-two patients with early-staging endometrial carcinoma were operated with laparoscopic comprehensive staging laparotomy from January 2019 to December 2021. At the same time, the SLN detection was performed by near-infrared fluorescence imaging tracer technology, in which the tracer was indocyanine green. Sixteen cases were injected with indocyanine green before laparoscopic surgery, and 16 cases were injected with indocyanine green before robot-assisted laparoscopic surgery. The operation index, postoperative complications, prognosis, and lymph node dissection were compared between the two groups. Results: (1) The mean age of patients in the robot group was (54.7±8.1) years old, and was (54.9±8.8) years old in the laparoscopic group. There were no significant difference between the two groups (t=0.06, P=0.951). (2) Intraoperative blood loss [(131±40) vs (169±57) ml], hemoglobin difference before and after surgery [(11.2±5.4) vs (15.5±5.7) g/L], the length of stay after operation [(6.2±1.3) vs (8.6±1.4) days] between the robot group and the laparoscopic group were compared, and the differences were statistically significant (all P<0.05). (3) SLNs were detected in all 16 patients in the robotic group, and a total of 41 SLNs were detected. SLNs were detected in 15 of the 16 patients in the laparoscopy group, and a total of 40 SLNs were detected. Compared with the laparoscopic group (15/16), the total detection rate of SLN in the robotic group (16/16), there were no statistical significance (χ²=1.03, P=0.310). Compared with the laparoscopic group (7/15), the SLN bilateral detection rate in the robotic group (10/16), there were also no significant difference (χ²=0.78, P=0.376). The number of lymph nodes detected in surgery group (16.6±4.1) were lower than those in the laparoscopy surgery group (21.0±7.1), while there were no statistically difference between the two groups (χ²=2.01, P=0.054). There was no tumor metastasis in the resected lymph nodes and SLN between the two groups. The false negative rate of SLN in diagnosing endometrial cancer postoperative lymph node metastasis was 0, and the negative predictive value was 100%. (4) The pelvic and retroperitoneal lymph nodes were divided into five regions, which were the left pelvis, the right pelvis, the presacral region, the deep inguinal region, and the abdominal aorta. The numbers of SLN of unilateral detection and bilateral pelvic detection between two groups showed no significant differences (all P>0.05). The left pelvis had the most SLN imaging in both groups, followed by the right pelvis, para-aortic, and deep groin. (5) There was one patient in both robotic group and laparoscopic group with postoperative complications, which were urinary retention and pelvic lymph node cyst respectively. There were no significant differences in the incidence of complications between the two groups (χ²=0.97, P=1.000). The median follow-up time after operation was 14 months (range 6-24 months). During the follow-up period, no local recurrence or distant metastasis was found between the two groups of endometrial cancer patients. Conclusions: Compared with the laparoscopic group, the robot group has less intraoperative blood loss and shorter postoperative hospital stay. The bilateral detection rate of SLN in the group was better than that of laparoscopy.

Antimony release and volatilization from rice paddy soils: Field and microcosm study

The fate of antimony (Sb) in submerged soils and the impact of common agricultural practices (e.g., manuring) on Sb release and volatilization is understudied. We investigated porewater Sb release and volatilization in the field and laboratory for three rice paddy soils. In the field study, the porewater Sb concentration (up to 107.1 μg L^-1) was associated with iron (Fe) at two sites, and with pH, Fe, manganese (Mn), and sulfate (SO₄^2-) at one site. The surface water Sb concentrations (up to 495.3 ± 113.7 μg L^-1) were up to 99 times higher than the regulatory values indicating a potential risk to aquaculture and rice agriculture. For the first time, volatile Sb was detected in rice paddy fields using a validated quantitative method (18.1 ± 5.2 to 217.9 ± 160.7 mg ha^-1 y^-1). We also investigated the influence of two common rice agriculture practices (flooding and manuring) on Sb release and volatilization in a 56-day microcosm experiment using the same soils from the field campaign. Flooding induced an immediate, but temporary, Sb release into the porewater that declined with SO₄^2-, indicating that SO₄^2- reduction may reduce porewater Sb concentrations. A secondary Sb release, corresponding to Fe reduction in the porewater, was observed in some of the microcosms. Our results suggest flooding-induced Sb release into rice paddy porewaters is temporary but relevant. Manuring the soils did not impact the porewater Sb concentration but did enhance Sb volatilization. Volatile Sb (159.6 ± 108.4 to 2237.5 ± 679.7 ng kg^-1 y^-1) was detected in most of the treatments and was correlated with the surface water Sb concentration. Our study indicates that Sb volatilization could be occurring at the soil-water interface or directly in the surface water and highlights that future works should investigate this potentially relevant mechanism.

Methyltransferase 1 is required for nonhomologous end-joining repair and renders hepatocellular carcinoma resistant to radiotherapy

BACKGROUND AND AIMS

Radiotherapy is an increasingly essential therapeutic strategy in the management of hepatocellular carcinoma (HCC). Nevertheless, resistance to radiotherapy is one of the primary obstacles to successful treatment outcomes. Hence, we aim to elucidate the mechanisms underlying radioresistance and identify reliable biotargets that would be inhibited to enhance the efficacy of radiotherapy in HCC.

APPROACH AND RESULTS

From a label-free quantitative proteome screening, we identified transfer RNA (tRNA; guanine-N [7]-) methyltransferase 1 (METTL1), a key enzyme for N7-methylguanosine (m⁷ G) tRNA modification, as an essential driver for HCC cells radioresistance. We reveal that METTL1 promotes DNA double-strand break (DSB) repair and renders HCC cells resistant to ionizing radiation (IR) using loss-of-function and gain-of-function assays in vitro and in vivo. Mechanistically, METTL1-mediated m⁷ G tRNA modification selectively regulates the translation of DNA-dependent protein kinase catalytic subunit or DNA ligase IV with higher frequencies of m⁷ G-related codons after IR treatment, thereby resulting in the enhancement of nonhomologous end-joining (NHEJ)-mediated DNA DSB repair efficiency. Clinically, high METTL1 expression in tumor tissue is significantly correlated with poor prognosis in radiotherapy-treated patients with HCC.

CONCLUSIONS

Our findings show that METTL1 is a critical enhancer for HCC cell NHEJ-based DNA repair following IR therapy. These findings give insight into the role of tRNA modification in messenger RNA translation control in HCC radioresistance.

[Transcriptomic analysis of the ΔPaLoc mutant of Clostridioides difficile and verification of its toxicity]

Objective: Comparative analyses of wild-type Clostridioides difficile 630 (Cd630) strain and pathogenicity locus (PaLoc) knockout mutant (ΔPaLoc) by using RNA-seq technology. Analysis of differential expression of Cd630 wild-type strain and ΔPaLoc mutant strain and measurement of its cellular virulence changes. Lay the foundation for the construction of an toxin-attenuated vaccine strain against Clostridioides difficile. Methods: Analysis of Cd630 and ΔPaLoc mutant strains using high-throughput sequencing (RNA-seq). Clustering differentially expressed genes and screening differentially expressed genes by DESeq software. Further analysis of differential genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Finally, cytotoxicity assays of ΔPaLoc and Cd630 strains were performed in the African monkey kidney epithelial cell (Vero) and the human colonic cell (Caco-2) lines. Results: The transcriptome data showed that the ΔPaLoc mutant toxin genes tcdA and tcdB were not transcribed. Compared to the wild-type strain, CD630_36010, CD630_020910,CD630_02080 and cel genes upregulated 17.92,11.40,8.93 and 7.55 fold, respectively. Whereas the hom2 (high serine dehydrogenase), the CD630_15810 (spore-forming protein), CD630_23230 (zinc-binding dehydrogenase) and CD630_23240 (galactitol 1-phosphate 5-dehydrogenase) genes were down-regulated by 0.06, 0.075, 0.133 and 0.183 fold, respectively. The GO and KEGG enrichment analyses showed that the differentially transcribed genes in ΔPaLoc were enriched in the density-sensing system, ABC transport system, two-component system, phosphotransferase (PTS) system, and sugar metabolism pathway, as well as vancomycin resistance-related pathways. Cytotoxicity assays showed that the ΔPaLoc mutant strain lost its virulence to Vero and Caco-2 cells compared to the wild-type Cd630 strain. Conclusion: Transcriptional sequencing analysis of the Cd630 and ΔPaLoc mutant strains showed that the toxin genes were not transcribed. Those other differential genes could provide a reference for further studies on the physiological and biochemical properties of the ΔPaLoc mutant strain. Cytotoxicity assays confirmed that the ΔPaLoc mutant lost virulence to Vero and Caco-2 cells, thus laying the foundation for constructing an toxin-attenuated vaccine strain against C. difficile.

Subnanometer Ion Channel Anion Exchange Membranes Having a Rigid Benzimidazole Structure for Selective Anion Separation

Ion-conductive polymers having a well-defined phase-separated structure show the potential application of separating mono- and bivalent ion separation. In this work, three side-chain-type poly(arylene ether sulfone)-based anion exchange membranes (AEMs) have been fabricated to investigate the effect of the stiffness of the polymer backbone within AEMs on the Cl^-/NO₃^- and Cl^-/SO₄^2- separation performance. Our investigations via small-angle X-ray scattering (SAXS), positron annihilation, and differential scanning calorimetry (DSC) demonstrate that the as-prepared AEM with a rigid benzimidazole structure in the backbone bears subnanometer ion channels resulting from the arrangement of the rigid polymer backbone. In particular, SAXS results demonstrate that the rigid benzimidazole-containing AEM in the wet state has an ion cluster size of 0.548 nm, which is smaller than that of an AEM with alkyl segments in the backbone (0.760 nm). Thus, in the electrodialysis (ED) process, the former exhibits a superior capacity of separating Cl^-/SO₄^2- ions relative to latter. Nevertheless, the benzimidazole-containing AEM shows an inability to separate the Cl^-/NO₃^- ions, which is possibly due to the similar ion size of the two. The higher rotational energy barrier (4.3 × 10^-3 Hartree) of benzimidazole units and the smaller polymer matrix free-volume (0.636%) in the AEM significantly contribute to the construction of smaller ion channels. As a result, it is believed that the rigid benzimidazole structure of this kind is a benefit to the construction of stable subnanometer ion channels in the AEM that can selectively separate ions with different sizes.

P-L11 Comparison of clinical efficacy between LAPS and ALPPS in the Treatment of Hepatitis B Virus-related Hepatocellular Carcinoma

Background

The aim of the study is to compare the safety and efficacy of modified ALPPS (laparoscopic microwave ablation and portal vein ligation for staged hepatectomy, LAPS) and classical associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in the treatment of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

Methods

Clinical data of patients with HBV-related HCC who underwent LAPS or ALPPS surgery in our institute from April 2013 to October 2020 were retrospectively analyzed.

Results

31 patients with HBV-related HCC were retrospectively collected in this study (LAPS = 8, ALPPS = 23). 7 patients with LAPS and 19 patients with ALPPS proceeded to resection (resection rate: 87.5% vs. 82.6%, P &gt; 0.05). The hypertrophy rate of future liver remnant (FLR) caused by ALPPS was higher than that of LAPS (24.3 vs. 11.7 mL/d, P = 0.024). Compared with the ALPPS, LAPS was associated with less blood loss (300ml vs. 40ml, P &lt; 0.001) during stage 1, lower comprehensive complication index (CCI) after stage 1 (8.7 vs. 0, P = 0.023) and lower total CCI (20.9 vs 0, P = 0.018) for two stages. Two years’ recurrence-free survival rate and over survival rate for ALPPS and LAPS were 17.3%, 34.3% (P = 0.105), and 28.9%, 100.0% (P = 0.011) respectively.

Conclusions

Compared with ALPPS, LAPS can reduce the occurrence of complications in patients with HBV-related HCC and improve patients’ prognoses.

METTL1 promotes hepatocarcinogenesis via m7 G tRNA modification-dependent translation control

BACKGROUND

N7 -methylguanosine (m7 G) modification is one of the most common transfer RNA (tRNA) modifications in humans. The precise function and molecular mechanism of m7 G tRNA modification in hepatocellular carcinoma (HCC) remain poorly understood.

METHODS

The prognostic value and expression level of m7 G tRNA methyltransferase complex components methyltransferase-like protein-1 (METTL1) and WD repeat domain 4 (WDR4) in HCC were evaluated using clinical samples and TCGA data. The biological functions and mechanisms of m7 G tRNA modification in HCC progression were studied in vitro and in vivo using cell culture, xenograft model, knockin and knockout mouse models. The m7 G reduction and cleavage sequencing (TRAC-seq), polysome profiling and polyribosome-associated mRNA sequencing methods were used to study the levels of m7 G tRNA modification, tRNA expression and mRNA translation efficiency.

RESULTS

The levels of METTL1 and WDR4 are elevated in HCC and associated with advanced tumour stages and poor patient survival. Functionally, silencing METTL1 or WDR4 inhibits HCC cell proliferation, migration and invasion, while forced expression of wild-type METTL1 but not its catalytic dead mutant promotes HCC progression. Knockdown of METTL1 reduces m7 G tRNA modification and decreases m7 G-modified tRNA expression in HCC cells. Mechanistically, METTL1-mediated tRNA m7 G modification promotes the translation of target mRNAs with higher frequencies of m7 G-related codons. Furthermore, in vivo studies with Mettl1 knockin and conditional knockout mice reveal the essential physiological function of Mettl1 in hepatocarcinogenesis using hydrodynamics transfection HCC model.

CONCLUSIONS

Our work reveals new insights into the role of the misregulated tRNA modifications in liver cancer and provides molecular basis for HCC diagnosis and treatment.

[Analysis on the imported Coronavirus Disease 2019 related cluster epidemic in rural areas of Chengdu]

An epidemiological investigation was carried out on a local cluster of outbreak caused by imported cases of Coronavirus Disease 2019 (COVID-19) in rural areas of Chengdu in December 2020, to find out the source of infection and the chain of transmission. According to Prevention and Control Protocol for COVID-19 (Version 7), field epidemiological investigation was adopted, combined with big data technology, video image investigation, gene sequencing and other methods to carry out investigation into COVID-19 cases and infections source tracing, analyze the epidemiological association, and map the chain of transmission. From December 7 to 17, 2020, 13 local COVID-19 confirmed cases and 1 asymptomatic case were diagnosed in Chengdu, of which 12 cases (85.71%) had a history of residence and activity in the village courtyard of Taiping (TP), Pidu (P) District, Chengdu. From November 8, 2020 to November 28, 2020, a group of inbound people form Nepal were transferred to the designated entry personnel quarantine hotel of P District which was adjacent to the TP village. During quarantine, there were 5 cases who tested positive for COVID-19. Through gene sequencing alignment, genes of local cases and Nepalese imported cases from the same period are homologous, all belong to the lineage of L2.2.3 (B.1.36 according to Pangolin lineage typing method). According to the results of field epidemiological investigation and gene sequencing analysis, the index case was most likely infected by contact with household waste of quarantine site. Under the situation of normalization prevention and control of COVID-19, sentinel monitoring of fever clinics in primary medical institutions is the key to early detection of the epidemic. The multi-department joint epidemiological investigation and the application of gene technology are the core links of the investigation and traceability of modern infectious diseases. The allocation of public health resources in rural areas needs to be strengthened. We need to improve the capacity for early surveillance and early warning of the epidemic in rural areas.

Insufficient Radiofrequency Ablation Promotes Hepatocellular Carcinoma Metastasis Through N6-Methyladenosine mRNA Methylation-Dependent Mechanism

BACKGROUND AND AIMS

The dynamic N6-methyladenosine (m⁶ A) mRNA modification is essential for acute stress response and cancer progression. Sublethal heat stress from insufficient radiofrequency ablation (IRFA) has been confirmed to promote HCC progression; however, whether m⁶ A machinery is involved in IRFA-induced HCC recurrence remains open for study.

APPROACH AND RESULTS

Using an IRFA HCC orthotopic mouse model, we detected a higher level of m⁶ A reader YTH N6-methyladenosine RNA binding protein 1-3 (YTHDF1) in the sublethal-heat-exposed transitional zone close to the ablation center than that in the farther area. In addition, we validated the increased m⁶ A modification and elevated YTHDF1 protein level in sublethal-heat-treated HCC cell lines, HCC patient-derived xenograft (PDX) mouse model, and patients' HCC tissues. Functionally, gain-of-function/loss-of-function assays showed that YTHDF1 promotes HCC cell viability and metastasis. Knockdown of YTHDF1 drastically restrains the tumor metastasis evoked by sublethal heat treatment in tail vein injection lung metastasis and orthotopic HCC mouse models. Mechanistically, we found that sublethal heat treatment increases epidermal factor growth receptor (EGFR) m⁶ A modification in the vicinity of the 5' untranslated region and promotes its binding with YTHDF1, which enhances the translation of EGFR mRNA. The sublethal-heat-induced up-regulation of EGFR level was further confirmed in the IRFA HCC PDX mouse model and patients' tissues. Combination of YTHDF1 silencing and EGFR inhibition suppressed the malignancies of HCC cells synergically.

CONCLUSIONS

The m⁶ A-YTHDF1-EGFR axis promotes HCC progression after IRFA, supporting the rationale for targeting m⁶ A machinery combined with EGFR inhibitors to suppress HCC metastasis after RFA.

P–547 Single-cell RNA sequencing identifies molecular regulations associated with poor maturation performance on rescue in vitro matured oocytes

Study question

What is the transcriptome signature associated with rescuein vitro matured (rIVM) oocytes?

Summary answer

GATA–1/CREB1/WNT signaling axis was repressed in rIVM oocytes of poor quality.

What is known already

rIVM aims to produce mature oocytes (MII) for in vitro fertilization (IVF) through IVM of immature oocytes collected from stimulated ovaries. It is less popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress, and the absence of cumulus cell support in oocytes could account for the failure of rIVM.

Study design, size, duration

We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo (IVO) oocytes (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors, followed by studying the maternal age effect and ovarian responses on rIVM oocyte transcriptomes.

Participants/materials, setting, methods

Human oocytes were collected from donors aged 28–41 years with a body mass index of &lt; 30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analyzed. Selected genes in therIVM vs. IVO comparison were validated by quantitative real-time PCR.

Main results and the role of chance

The transcriptome profiles of rIVM/IVO showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least two-fold change and adjusted p &lt; 0.05) were found to be enriched in metabolic processes, biosynthesis, and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/β-catenin signaling in rIVM when compared with IVO oocytes. We found that estradiol level exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio). rIVM oocytes with higher MII ratio showed over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor outcomes of rIVM, we compared oocytes collected from young donors with high MII ratio versus donors of advanced maternal age and revealed CREB1was an important regulator in rIVM. Our study identified GATA–1/CREB1/WNT signaling was repressed in both rIVM condition and rIVM oocytes of low-quality.

Limitations, reasons for caution

In the rIVM oocytes of high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle so polar body extrusion was the only indicator.

Wider implications of the findings: This study showed that GATA–1/CREB1/WNT signaling and antioxidant actions were repressed in rIVM condition and was further downregulated in rIVM oocytes of low-quality, providing us the foundation of subsequent follow-up research on human subjects.

Trial registration number

Not applicable

Single-cell RNA sequencing identifies molecular targets associated with poor in vitro maturation performance of oocytes collected from ovarian stimulation

STUDY QUESTION

What is the transcriptome signature associated with poor performance of rescue IVM (rIVM) oocytes and how can we rejuvenate them?

SUMMARY ANSWER

The GATA-1/CREB1/WNT signalling axis was repressed in rIVM oocytes, particularly those of poor quality; restoration of this axis may produce more usable rIVM oocytes.

WHAT IS KNOWN ALREADY

rIVM aims to produce mature oocytes (MII) for IVF through IVM of immature oocytes collected from stimulated ovaries. It is not popular due to limited success rate in infertility treatment. Genetic aberrations, cellular stress and the absence of cumulus cell support in oocytes could account for the failure of rIVM.

STUDY DESIGN, SIZE, DURATION

We applied single-cell RNA sequencing (scRNA-seq) to capture the transcriptomes of human in vivo oocytes (IVO) (n = 10) from 7 donors and rIVM oocytes (n = 10) from 10 donors. The effects of maternal age and ovarian responses on rIVM oocyte transcriptomes were also studied. In parallel, we studied the effect of gallic acid on the maturation rate of mouse oocytes cultured in IVM medium with (n = 84) and without (n = 85) gallic acid.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human oocytes were collected from donors aged 28-41 years with a body mass index of <30. RNA extraction, cDNA generation, library construction and sequencing were performed in one preparation. scRNA-seq data were then processed and analysed. Selected genes in the rIVM versus IVO comparison were validated by quantitative real-time PCR. For the gallic acid study, we collected immature oocytes from 5-month-old mice and studied the effect of 10-μM gallic acid on their maturation rate.

MAIN RESULTS AND THE ROLE OF CHANCE

The transcriptome profiles of rIVM/IVO oocytes showed distinctive differences. A total of 1559 differentially expressed genes (DEGs, genes with at least 2-fold change and adjusted P < 0.05) were found to be enriched in metabolic processes, biosynthesis and oxidative phosphorylation. Among these DEGs, we identified a repression of WNT/β-catenin signalling in rIVM when compared with IVO oocytes. We found that oestradiol levels exhibited a significant age-independent correlation with the IVO mature oocyte ratio (MII ratio) for each donor. rIVM oocytes from women with a high MII ratio were found to have over-represented cellular processes such as anti-apoptosis. To further identify targets that contribute to the poor clinical outcomes of rIVM, we compared oocytes collected from young donors with a high MII ratio with oocytes from donors of advanced maternal age and lower MII ratio, and revealed that CREB1 is an important regulator. Thus, our study identified that GATA-1/CREB1/WNT signalling was repressed in both rIVM oocytes versus IVO oocytes and in rIVM oocytes of lower versus higher quality. Consequently we investigated gallic acid, as a potential antioxidant substrate in human rIVM medium, and found that it increased the mouse oocyte maturation rate by 31.1%.

LARGE SCALE DATA

Raw data from this study can be accessed through GSE158539.

LIMITATIONS, REASONS FOR CAUTION

In the rIVM oocytes of the high- and low-quality comparison, the number of samples was limited after data filtering with stringent selection criteria. For the oocyte stage identification, we were unable to predict the presence of oocyte spindle, so polar body extrusion was the only indicator.

WIDER IMPLICATIONS OF THE FINDINGS

This study showed that GATA-1/CREB1/WNT signalling was repressed in rIVM oocytes compared with IVO oocytes and was further downregulated in low-quality rIVM oocytes, providing us the foundation of subsequent follow-up research on human oocytes and raising safety concerns about the clinical use of rescued oocytes.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Collaborative Research Fund, Research Grants Council, C4054-16G, and Research Committee Funding (Research Sustainability of Major RGC Funding Schemes), The Chinese University of Hong Kong. The authors have no conflicts of interest to declare.

Asymmetric expression patterns of B- and C-class MADS-box genes correspond to the asymmetrically specified androecial identities of Canna indica

Canna indica is a common ornamental plant with asymmetric flowers having colourful petaloid staminodes. The only fertile stamen comprises a one-theca anther and a petaloid appendage and represents the lowest stamen number in the order Zingiberales. The molecular mechanism for the asymmetric androecial petaloidy remains poorly understood. Here, we studied the identity specification in Canna stamen. We observed four types of abnormal flower in terms of androecium identity transformation and analysed the corresponding floral symmetry changes. We further tested the expression patterns of B- and C-class MADS-box genes using in situ hybridization in normal Canna stamen. Homeotic conversions in the androecium were accompanied by floral symmetry changes, and the asymmetric stamen is key in contributing to the floral asymmetry. Both B- and C-class genes exhibited higher expression levels in the anther primordium than in other androecial parts. This asymmetric expression pattern precisely corresponded to the asymmetric identities of the Canna androecium. We identified C. indica as a model species for studying androecial organ identity and floral symmetry synthetically in Zingiberales. We hypothesized that homeotic genes specify floral organ identity in a putative dose-dependent manner. The results add to the current understanding of organ identity-related floral symmetry.

[CRISPR/Cas9-mediated TEAD1 knockout induces phenotypic modulation of corpus cavernosum smooth muscle cells in diabetic rats with erectile dysfunction]

OBJECTIVE

To construct a corpus cavemosum smooth muscle cell (CCSMCs) line with TEAD1 knockout from diabetic rats with erectile dysfunction (ED) using CRISPR/Cas9 technology and explore the role of TEAD1 in phenotypic modulation of CCSMCs in diabetic rats with ED.

OBJECTIVE

Models of diabetic ED were established in male Sprague-Dawley rats by intraperitoneal injection of streptozotocin. CCSMCs from the rat models were primarily cultured and identified with immunofluorescence assay. Three sgRNAs (sgRNA-1, sgRNA-2 and sgRNA-3) were transfected via lentiviral vectors into 293T cells to prepare the sgRNA-Cas9 lentivirus. CCSMCs from diabetic rats with ED were infected by the lentivirus, and the cellular expression of TEAD1 protein was detected using Western blotting. In CCSMCs infected with the sgRNA-Cas9 lentivirus (CCSMCs-sgRNA-2), or the empty lentiviral vector (CCSMCs-sgRNA-NC) and the blank control cells (CCSMCs-CK), the expressions of cellular phenotypic markers SMMHC, calponin and PCNA at the mRNA and protein levels were detected using real-time fluorescence quantitative RT-PCR (qRT-PCR) and Western blotting, respectively.

OBJECTIVE

The primarily cultured CCSMCs from diabetic rats with ED showed a high α-SMA-positive rate of over 95%. The recombinant lentivirus of TEAD1-sgRNA was successfully packaged, and stable TEAD1-deficient CCSMC lines derived from diabetic rat with ED were obtained. Western blotting confirmed that the protein expression of TEAD1 in TEAD1-sgRNA-2 group was the lowest (P < 0.05), and this cell line was used in subsequent experiment. The results of qRT-PCR and Western blotting showed significantly up-regulated expressions of SMMHC and calponin (all P < 0.05) and down-regulated expression of PCNA (all P < 0.05) at both the mRNA and protein levels in TEAD1-deficient CCSMCs from diabetic rats with ED.

OBJECTIVE

We successfully constructed a stable CCSMCs line with CRISPR/Cas9-mediated TEAD1 knockout from diabetic rats with ED. TEAD1 gene knockout can induce phenotype transformation of the CCSMCs from diabetic rats with ED from the synthetic to the contractile type.

Cation Exchange Membranes Coated with Polyethyleneimine and Crown Ether to Improve Monovalent Cation Electrodialytic Selectivity

Developing monovalent cation permselective membranes (MCPMs) with high-efficient permselectivity is the core concern in specific industrial applications. In this work, we have fabricated a series of novel cation exchange membranes (CEMs) based on sulfonated polysulfone (SPSF) surface modification by polyethyleneimine (PEI) and 4′-aminobenzo-12-crown-4 (12C4) codeposited with dopamine (DA) successively, which was followed by the cross-linking of glutaraldehyde (GA). The as-prepared membranes before and after modification were systematically characterized with regard to their structures as well as their physicochemical and electrochemical properties. Particularly, the codeposition sequence of modified ingredients was investigated on galvanostatic permselectivity to cations. The modified membrane (M-12C4-0.50-PEI) exhibits significantly prominent selectivity to Li⁺ ions (PMg2+Li+ = 5.23) and K⁺ ions (PMg2+K+ = 13.56) in Li⁺/Mg²⁺ and K⁺/Mg²⁺ systems in electrodialysis (ED), which is far superior to the pristine membrane (M-0, PMg2+Li+ = 0.46, PMg2+K+ = 1.23) at a constant current density of 5.0 mA·cm⁻². It possibly arises from the synergistic effects of electrostatic repulsion (positively charged PEI), pore-size sieving (distribution of modified ingredients), and specific interaction effect (12C4 ~Li⁺). This facile strategy may provide new insights into developing selective CEMs in the separation of specific cations by ED.

Nomogram development and validation to predict hepatocellular carcinoma tumor behavior by preoperative gadoxetic acid-enhanced MRI

OBJECTIVES

Pretreatment evaluation of tumor biology and microenvironment is important to predict prognosis and plan treatment. We aimed to develop nomograms based on gadoxetic acid-enhanced MRI to predict microvascular invasion (MVI), tumor differentiation, and immunoscore.

METHODS

This retrospective study included 273 patients with HCC who underwent preoperative gadoxetic acid-enhanced MRI. Patients were assigned to two groups: training (N = 191) and validation (N = 82). Univariable and multivariable logistic regression analyses were performed to investigate clinical variables and MRI features' associations with MVI, tumor differentiation, and immunoscore. Nomograms were developed based on features associated with these three histopathological features in the training cohort, then validated, and evaluated.

RESULTS

Predictors of MVI included tumor size, rim enhancement, capsule, percent decrease in T1 images (T1_D%), standard deviation of apparent diffusion coefficient, and alanine aminotransferase levels, while capsule, peritumoral enhancement, mean relaxation time on the hepatobiliary phase (T1_E), and alpha-fetoprotein levels predicted tumor differentiation. Predictors of immunoscore included the radiologic score constructed by tumor number, intratumoral vessel, margin, capsule, rim enhancement, T1_D%, relaxation time on plain scan (T1_P), and alpha-fetoprotein and alanine aminotransferase levels. Three nomograms achieved good concordance indexes in predicting MVI (0.754, 0.746), tumor differentiation (0.758, 0.699), and immunoscore (0.737, 0.726) in the training and validation cohorts, respectively.

CONCLUSION

MRI-based nomograms effectively predict tumor behaviors in HCC and may assist clinicians in prognosis prediction and pretreatment decisions.

KEY POINTS

• This study developed and validated three nomograms based on gadoxetic acid-enhanced MRI to predict MVI, tumor differentiation, and immunoscore in patients with HCC. • The pretreatment prediction of tumor microenvironment may be useful to guide accurate prognosis and planning of surgical and immunological therapies for individual patients with HCC.

Irreversible electroporation induces CD8+ T cell immune response against post-ablation hepatocellular carcinoma growth

Ablative treatment evokes antitumor immunity, but knowledge on the emerging irreversible electroporation (IRE)-induced immunity in hepatocellular carcinoma (HCC) is limited. To investigate the immune effects induced by IRE and its role in preventing post-ablation HCC progression, a C57BL/6J mouse model bearing subcutaneous H22 hepatoma was employed. IRE treatment significantly suppresses HCC growth, and treated mice are tumor-free after secondary tumor injection and show increased splenic interferon-gamma (IFN-γ)+CD8⁺ T cells. Additionally, more CD8⁺ T and dendritic cells, but not CD4⁺ T, B or NK cells, infiltrate into peri-ablation zones after IRE at day 7. Depletion of CD8⁺ T cells induces local tumor regrowth and distant metastasis after IRE. Vaccination using IRE-processed H22 lysates prevents tumorigenesis in mice, suggesting a protective immune response. IRE also alleviates immunosuppression by reducing local and splenic Treg and PD-1⁺ T cells. Regarding mechanism, IRE induces cell necrosis and significant release of danger-associated molecular patterns including ATP, high mobility group box 1 and calreticulin that are pivotal to CD8⁺ T cell immunity. Together, IRE is a promising approach to evoke CD8⁺ T cell immunity, which help prevent post-ablation HCC progression.

A functional mutation in the AMPD1 promoter region affects promoter activity and breast meat freshness in chicken

Freshness is an important index to determine the quality deterioration (protein degradation and changes in appearance) of chilled chicken meat and is a primary consideration of consumers. Adenosine monophosphate deaminase 1 (AMPD1) catalyzes the deamination of adenosine monophosphate to inosine monophosphate in skeletal muscle and is the rate-limiting step in the purine nucleotide cycle. Inosine monophosphate is regarded as an important indicator of meat freshness in chicken. This study investigated the association of polymorphisms in the chicken AMPD1 promoter region with meat freshness during freezing storage. An SNP (c. -905G>A) was found to be associated with the freshness (K-value) of chicken breast meat. Chickens with the AA genotype had significantly lower K-values than those with GG and AG genotypes (P < 0.01). Individuals with the AA genotype also had higher breast meat AMPD1 mRNA levels than did those with the GG and AG genotypes (P < 0.01, P < 0.05). A luciferase assay revealed that genotype AA had greater transcriptional activity than genotype GG. Transcription factor binding site analysis identified distinct putative transcription factor binding sites in the two alleles of mutation site c. -905. In summary, we identified an SNP (c. -905G>A) in the promoter region of the AMPD1 gene that may modulate the binding affinity of different transcription factors to control AMPD1 expression and affect the freshness K-value of chicken meat.