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Abstract Currently, conventional dimethoxymethane synthesis methods are environmentally unfriendly. Here, we report a photo-redox catalysis system to generate dimethoxymethane using a silver and tungsten co-modified blue titanium dioxide catalyst (Ag.W-BTO) by coupling CO2 reduction and CH3OH oxidation under mild conditions. The Ag.W-BTO structure and its electron and hole transfer are comprehensively investigated by combining advanced characterizations and theoretical studies. Strikingly, Ag.W-BTO achieve a record photocatalytic activity of 5702.49 µmol g−1 with 92.08% dimethoxymethane selectivity in 9 h of ultraviolet-visible irradiation without sacrificial agents. Systematic isotope labeling experiments, in-situ diffuse reflectance infrared Fourier-transform analysis, and theoretical calculations reveal that the Ag and W species respectively catalyze CO2 conversion to *CH2O and CH3OH oxidation to *CH3O. Subsequently, an asymmetric carbon-oxygen coupling process between these two crucial intermediates produces dimethoxymethane. This work presents a CO2 photocatalytic reduction system for multi-carbon production to meet the objectives of sustainable economic development and carbon neutrality.

Abstract To realize economically feasible electrochemical CO2 conversion, achieving a high partial current density for value-added products is particularly vital. However, acceleration of the hydrogen evolution reaction due to cathode flooding in a high-current-density region makes this challenging. Herein, we find that partially ligand-derived Ag nanoparticles (Ag-NPs) could prevent electrolyte flooding while maintaining catalytic activity for CO2 electroreduction. This results in a high Faradaic efficiency for CO (>90%) and high partial current density (298.39 mA cm‒2), even under harsh stability test conditions (3.4 V). The suppressed splitting/detachment of Ag particles, due to the lipid ligand, enhance the uniform hydrophobicity retention of the Ag-NP electrode at high cathodic overpotentials and prevent flooding and current fluctuations. The mass transfer of gaseous CO2 is maintained in the catalytic region of several hundred nanometers, with the smooth formation of a triple phase boundary, which facilitate the occurrence of CO2RR instead of HER. We analyze catalyst degradation and cathode flooding during CO2 electrolysis through identical-location transmission electron microscopy and operando synchrotron-based X-ray computed tomography. This study develops an efficient strategy for designing active and durable electrocatalysts for CO2 electrolysis.

Abstract The design of high‐entropy single‐atom catalysts (HESAC) with 5.2 times higher entropy compared to single‐atom catalysts (SAC) is proposed, by using four different metals (FeCoNiRu‐HESAC) for oxygen reduction reaction (ORR). Fe active sites with intermetallic distances of 6.1 Å exhibit a low ORR overpotential of 0.44 V, which originates from weakening the adsorption of OH intermediates. Based on density functional theory (DFT) findings, the FeCoNiRu‐HESAC with a nitrogen‐doped sample were synthesized. The atomic structures are confirmed with X‐ray photoelectron spectroscopy (XPS), X‐ray absorption (XAS), and scanning transmission electron microscopy (STEM). The predicted high catalytic activity is experimentally verified, finding that FeCoNiRu‐HESAC has overpotentials of 0.41 and 0.37 V with Tafel slopes of 101 and 210 mVdec−1 at the current density of 1 mA cm−2 and the kinetic current densities of 8.2 and 5.3 mA cm−2, respectively, in acidic and alkaline electrolytes. These results are comparable with Pt/C. The FeCoNiRu‐HESAC is used for Zinc–air battery applications with an open circuit potential of 1.39 V and power density of 0.16 W cm−2. Therefore, a strategy guided by DFT is provided for the rational design of HESAC which can be replaced with high‐cost Pt catalysts toward ORR and beyond.

Objective: Active surveillance (AS) has been suggested as a management option for low-risk papillary thyroid microcarcinoma (PTMC). However, the currently proposed selection criteria for AS application do not consider various clinical factors. The purpose of this study was to analyze clinical factors related to recurr ence that could be confirmed preoperatively in patients who underwent surgery for PTMC and to identify factors worth considering when deciding whether to apply AS. Materials and methods: Data were collected from patients with PTMC who underwent surgical treatment at Chungnam National University Hospital. A retrospective cohort was established according to the presence or absence of recurrence during the follow-up period. In total, 2717 patients were enrolled, of whom 60 experienced recurrence. Various clinical factors that could be identified before surgery were analyzed. Results: The relationship between various clinical factors that could be confirmed preoperatively and recurrence was confirmed through Cox regressi on analysis and Kaplan–Meier curve analysis. BRAF mutation and the tall cell variant were significantly more common in patients with recurrence. In patients aged 55 years or older, the risk of recurrence was lower than in younger patients, while the recurrence-free survival (RFS) rate was higher. Conclusion: When choosing between surgical treatment or AS in PTMC patients, additional consideration of the patient’s clinical factors, such as age and BRAF mutation status, may be required in addition to the existing criteria.

Abstract Electrocatalytic CO2‐to‐formate conversion is considered an economically viable process. In general, Zn‐based nanomaterials are well‐known to be highly efficient electrocatalysts for the conversion of CO2 to CO, but seldom do they exhibit excellent selectivity toward formate. In this article, we demonstrate that a heterointerface catalyst ZnO/ZnSnO3 with nanosheet morphology shows enhanced selectivity with a maximum Faradaic efficiency (FE) of 86% at −0.9 V versus reversible hydrogen electrode and larger current density for the conversion of CO2 to formate than pristine ZnO and ZnSnO3. In particular, the FEs of the C1 products (CO + HCOO−) exceed 98% over the potential window. The experimental measurements combined with theoretical calculations revealed that the ZnO in ZnO/ZnSnO3 heterojunction delivers the valence electron depletion and accordingly optimizes Zn d‐band center, which results in moderate Zn–O hybridization of HCOO* and weakened Zn–C hybridization of competing COOH*, thus greatly boosting the HCOOH generation. Our study highlights the importance of charge redistribution in catalysts on the selectivity of electrochemical CO2 reduction.

We report the growth of single crystals and X-ray diffraction characterization of the quasi-one-dimensional spin chain compound, Li2CuO2. The single crystals were grown using the high-temperature solution growth technique. The resulting blade-shaped crystals exhibit a shiny black color, with dimensions reaching several millimeters along the crystallographic b-axis. The as-grown crystals were characterized using powder X-ray diffraction and Laue back reflection. The I-centered orthorhombic, Immm, structure was confirmed. Crystal structure parameters were determined to be a = 3.6744 Å, b = 2.8600 Å, and c = 9.4257 Å from Rietveld analysis. Our work helps to remove obstacles to the synthesis and study of a model cuprate system, Li2CuO2, facilitating the use of experimental probes that require sizable crystals.

Objective The purpose of our study is to develop a spoken dialogue system (SDS) for pain questionnaire in patients with spinal disease. We evaluate user satisfaction and validated the performance accuracy of the SDS in medical staff and patients. Methods The SDS was developed to investigate pain and related psychological issues in patients with spinal diseases based on the pain questionnaire protocol. We recognized patients’ various answers, summarized important information, and documented them. User satisfaction and performance accuracy were evaluated in 30 potential users of SDS, including doctors, nurses, and patients and statistically analyzed. Results The overall satisfaction score of 30 patients was 5.5 ± 1.4 out of 7 points. Satisfaction scores were 5.3 ± 0.8 for doctors, 6.0 ± 0.6 for nurses, and 5.3 ± 0.5 for patients. In terms of performance accuracy, the number of repetitions of the same question was 13, 16, and 33 (13.5%, 16.8%, and 34.7%) for doctors, nurses, and patients, respectively. The number of errors in the summarized comment by the SDS was 5, 0, and 11 (5.2%, 0.0%, and 11.6 %), respectively. The number of summarization omissions was 7, 5, and 7 (7.3%, 5.3%, and 7.4%), respectively. Conclusion This is the first study in which voice-based conversational artificial intelligence (AI) was developed for a spinal pain questionnaire and validated by medical staff and patients. The conversational AI showed favorable results in terms of user satisfaction and performance accuracy. Conversational AI can be useful for the diagnosis and remote monitoring of various patients as well as for pain questionnaires in the future.

Abstract Cancer immunoediting drives the adaptation of tumor cells to host immune surveillance. Previously, we have demonstrated that immunoediting driven by cytotoxic T lymphocytes (CTLs) enriches NANOG+ tumor cells with immune-refractory properties. Here, we found that CTL-mediated immune pressure triggered cross-resistance of tumor cells to the complement system, a part of the innate immune system. In this process, NANOG upregulated the membrane-bound complement regulatory protein (mCRP) CD59 through promoter occupancy, thereby contributing to the resistance of tumor cells against complement-dependent cytotoxicity (CDC). Notably, targeting of NANOG sensitized the immune-refractory tumor cells to trastuzumab-mediated CDC. Collectively, our results revealed a possible mechanism through which selection imposed by T-cell based immunotherapy triggered complement-resistant phenotypes in the tumor microenvironment (TME), by establishing a firm molecular link between NANOG and CD59 in immune-edited tumor cells. We believe these results hold important implications for the clinical application of CDC-mediated therapeutic antibody.

Though stannic oxides can catalyze CO2 electroreduction to formate, the stability of these catalysts has been limited. Here, the authors demonstrate stable fluorine-doped SnO2 materials toward formate production at current densities of >300 mA/cm2.

Although ruthenium nanomaterials have proven to be effective catalysts for H2 evolution, there is still room for activity improvements. Here, authors develop an efficient Ru/HfO2 electrocatalyst with tuned Ru-O-Hf bonds and oxygen vacancies that shows high activities for alkaline H2 evolution.

Background and Objective The numbers of prescriptions for continuous positive airway pressure and automatic positive airway pressure (APAP) machines have increased dramatically since the Korean government changed national health insurance coverage. This study examined adherence to APAP therapy in patients with obstructive sleep apnea who completed the 3-month adaptation period required by the insurance service, and evaluated the factors predictive of good adherence. Methods We retrospectively reviewed the medical records of a total of 315 patients who received APAP prescriptions between July 2018 and December 2019. After screening, 189 patients were analyzed. Patients were divided into an adherent (AD) group and a non-adherent (NAD) group based on 9 months’ APAP adherence. Patient demographics, medical history, body mass index and pretreatment polysomnography results, as well as APAP therapy adherence-related variables, the 90th percentile pressure, residual apnea hypopnea status, and type of devices or managers were compared between the two groups. Results We found mean usage times, mean pressures, days with ≥ 4 hours of use a day, and 90th percentile pressures differed significantly between the AD and NAD groups. The device-related data at months 1 and 3 and 9 were similar. One type of device performed differently compared to the other devices, but this did not affect adherence. Conclusions The mean pressure and 90th percentile pressure were the main determinants of adherence in patients who passed a 3-month compliance assessment conducted by the Korean National Institute of Health. The data on adherence at months 1, 3 and 9 were similar.

While single, dispersed atoms enable efficient atomic utilization, controllably preparing single-atom dimers remains challenging. Here, authors prepare nickel-cobalt single-atom dimers as high-performance pH-universal H2 evolution electrocatalysts.

The poor catalyst stability for oxygen evolution in acidic media has been a long-time issue. Here, authors demonstrate iridium on MoO3 exhibits a low overpotential for oxygen evolution and excellent durability in acidic media due to the high oxidation state of iridium metal on MoO3.

Acute mesenteric ischemia is a state in which intestinal infarction can be caused by a sudden decrease in blood flow. A 68-year-old man was transferred to Hanyang University Guri hospital with abdominal pain. A computed tomography scan performed before the transfer showed no abnormal findings. Examination and evaluation revealed abnormal electrocardiogram findings and increased troponin I. Although emergency coronary angiography was normal, the patient continued to complain of severe abdominal pain. A computed tomography scan showed occlusion of the superior mesenteric artery. Percutaneous aspiration embolectomy was successfully performed prior to surgery, and subsequent laparoscopic exploration revealed an area of bowel necrosis which was then resected. The length of the small intestine remaining after resection measured 1.6 m. On postoperative Day 6, the patient began a soft food diet and was prescribed medication after being diagnosed with atrial fibrillation. He was discharged on the 13th postoperative day without postoperative complications.

A vibration-damping steel panel is used for lightweight vehicles to block any noise subjected to the passenger cabin replacing heavy fiber-based insulators. Conventional weld joining methods often encounter problems due to the presence of viscoelastic compounds reducing the joint quality and making the joining process unproductive. In this work, we present experimental results that show the self-piercing riveting (SPR) process can be used to produce high-quality joints between vibration-damping steel and (i) commonly used steel alloy (SPFC590DP), (ii) carbon-fiber-reinforced-plastic (CFRP) panels. Various die shapes are used to investigate the resulting interlock width and bottom thickness of the joints and tensile shear load tests were performed to evaluate the joining strength. The results show that high-quality joints between vibration-damping steel and the steel alloy are possible for all the dye types and panel configurations, used in this study, producing up to 6.2 kN of tensile shear load. High-quality joints were also possible with CFRP producing up to 4.0 kN, however, acceptable joints were formed only when the CFRP panels were on top during the riveting process due to severe cracking.

A sand dam is an old technology used to trap sand materials and store water in dry riverbeds. Besides the volume of sand stored, the water storage and supply capacity of the sand dam depends principally on material properties including hydraulic conductivity (K) and the specific yield (Sy). In this study, the water supply capacity of a sand dam, applied in South Korea with a modified scheme, was analyzed. Imported sand materials were placed in three layers, and perforated drain pipes were installed to abstract the water to a collection tank. Using a Modular Finite-Difference Groundwater Flow (MODFLOW) model, the drain pipe discharge related to aquifer properties and supply capacity of a sand dam was evaluated. Using the model, the productivity of the sand storage with several cases of inflow conditions was assessed. For the period from 9 March 2020 to 16 May 2022, the results of calculation of water supply for the installation and operation of new sand dam are as follows. Regarding the actual inflow condition, compared to the average water supply of the existing water intake source, the sand dam installation increased water supply by 61.6%, and the sand dam installation showed an effect of improving the water supply by 36.0% for the minimum water supply. The calculated water supply for the condition where the inflow was reduced by 50% showed an effect of improving water supply by over 70% on average due to the installation of the sand dam. The findings would be a benchmark for future expansions of the scheme in related places, and management and maintenance of the system.

Abstract Ru nanoparticles (NPs) and single atoms (SAs)‐based materials have been investigated as alternative electrocatalysts to Pt/C for hydrogen evolution reaction (HER). Exploring the dominant role of atomic‐ and nano‐ruthenium as active sites in acidic and alkaline media is very necessary for optimizing the performance. Herein, an electrocatalyst containing both Ru SAs and NPs anchored on defective carbon (RuSA+NP/DC) has been synthesized via a Ru–alginate metal–organic supramolecules conversion method. RuSA+NP/DC exhibits low overpotentials of 16.6 and 18.8 mV at 10 mA cm−2 in acidic and alkaline electrolytes, respectively. Notably, its mass activities are dramatically improved, which are about 1.1 and 2.4 times those of Pt/C at an overpotential of 50 mV in acidic and alkaline media, respectively. Theoretical calculations reveal that Ru SAs own the most appropriate H* adsorption strength and thus, plays a dominant role for HER in acid electrolyte, while Ru NPs facilitate the dissociation of H2O that is the rate‐determining step in alkaline electrolyte, leading to a remarkable HER activity.

Water oxidation is considered the bottleneck reaction for light-driven water splitting due to the sluggish kinetics and poor stability. Here, authors show metal- and heteroatom-doped carbons as effective catalysts for both electrochemical and photoelectrochemical water splitting.

Abstract Hybridization with conductive nanospecies has attracted intense research interest as a general effective means to improve the photocatalytic functionalities of nanostructured materials. To establish universal design rules for high‐performance hybrid photocatalysts, correlations between versatile roles of conductive species and interfacial interaction between hybridized species are systematically investigated through fine‐control of intersheet distance between photocatalytically active TiO2 and metallic reduced graphene oxide (rGO)/RuO2 nanosheets. Molecular‐level tailoring of intersheet distance and electronic coupling between 2D nanosheets can be successfully achieved by restacking of colloidal nanosheet mixture with variable‐sized organic intercalants. While the shortest intersheet distance between restacked TiO2 and rGO nanosheets leads to the highest visible‐light‐driven photocatalytic activity, the best UV–vis photocatalyst performance occurs for moderate intersheet spacing. These results highlight the greater sensitivity of photoinduced electronic excitation to the intersheet distance than that of interfacial charge transfer. The rGO nanosheet can function as effective charge transport pathway and cocatalyst within ≈1.7 nm distance from the semiconducting nanosheet, and as efficient stabilizer for hybridized photocatalyst within ≈1.8 nm. The present study underscores that the intercalative restacking of colloidal nanosheet mixture with intercalants enables molecular‐level control of distance between 2D inorganic/graphene nanosheets, which provides a rational design strategy for high‐performance hybrid photocatalysts.

Matrix metalloproteinase-11 (MMP-11) promote cancer invasion and metastasis through degrading the extracellular matrix. Protein degradation by MMP-11 in tumor cells may progressively suppress cancer surveillance activities with blocking immune response in breast cancer. The aim of study is to analyze clinicopathological parameters, molecular interactions and anticancer immune response in patients with MMP-11 expression and to provide candidate target drugs. We investigated the clinicopathologic parameters, specific gene sets, tumor antigenicity, and immunologic relevance according to MMP-11 expression in 226 and 776 breast cancer patients from the Hanyang University Guri Hospital (HUGH) cohort and The Cancer Genome Atlas (TCGA) data, respectively. We analyzed pathway networks and in vitro drug response. High MMP-11 expression was associated with worse survival rate in breast cancer from HUGH cohort and TCGA data (all p < 0.05). In analysis of immunologic gene sets, high MMP-11 expression was related to low immune response such as CD8+T cell, CD4+T cell and B cell. In silico cytometry, there was a decrease of cancer testis antigen and low tumor infiltrating lymphocyte in patient with high MMP-11 expression: activated dendritic cell, CD8+T cell, CD4+ memory T cell, and memory B cell. In pathway networks, MMP-11 was linked to the pathways including low immune response, response to growth hormone and catabolic process. We found that pictilisib and AZ960 effectively inhibited the breast cancer cell lines with high MMP-11 expression. Strategies making use of MMP-11-related hub genes could contribute to better clinical management/research for patients with breast cancer.

Abstract Sub‐nanometric particles (SNPs) of atomic cluster sizes have shown great promise in many fields such as full atom‐to‐atom utilization, but their precise production and stabilization at high mass loadings remain a great challenge. As a solution to overcome this challenge, a strategy allowing synthesis and preservation of SNPs at high mass loadings within multishell hollow metal–organic frameworks (MOFs) is demonstrated. First, alternating water‐decomposable and water‐stable MOFs are stacked in succession to build multilayer MOFs. Next, using controlled hydrogen bonding affinity, isolated water molecules are selectively sieved through the hydrophobic nanocages of water‐stable MOFs and transferred one by one to water‐decomposable MOFs. The transmission of water molecules via controlled hydrogen bonding affinity through the water‐stable MOF layers is a key step to realize SNPs from various types of alternating water‐decomposable and water‐stable layers. This process transforms multilayer MOFs into SNP‐embedded multishell hollow MOFs. Additionally, the multishell stabilizes SNPs by π‐backbonding allowing high conductivity to be achieved via the hopping mechanism, and hollow interspaces minimize transport resistance. These features, as demonstrated using SNP‐embedded multishell hollow MOFs with up to five shells, lead to high electrochemical performances including high volumetric capacities and low overpotentials in Li–O2 batteries.

Imaging the antiferromagnetic (AFM) domains facilitates the understanding and design of AFM spintronics but is still challenging. Here the authors show an imaging approach for antiphase domains in AFM Fe2Mo3O8 by resonantly scattered coherent soft X-rays, which is also applicable to collinear antiferromagnets.

There is growing interest in the fundamental understanding of the voltage decay mechanism in Li-excess layered cathode materials. Here, the authors report a multilateral and macroscopic analysis that considers interaction between oxygen and atomic arrangement of Li1+x Ni y Co z Mn1−x−y−z O2.

Nanomaterials exhibit extraordinary properties based on their size, shape, chemical composition, and crystal structure. Owing to their unique properties nanomaterials are preferred over their bulk counterparts for a number of applications. Although conventional physical and chemical routes were established for the massive production of nanomaterials, there are some drawbacks such as environmental burden and high cost that cannot be disregarded. Recently, there has been great interest toward the green synthesis of inorganic nanomaterials. It has been reported that dissimilatory metal reduction by microorganisms is a cost-effective process to remediate toxic organic and inorganic compounds under anaerobic conditions. Particularly, members of the Shewanella genus have been utilized to produce various biogenic nanomaterials with unique micro/nanostructured morphologies through redox transformations as well as to remove harmful metals and metalloids in eco-efficient and environment-friendly methods under ambient conditions. In the present mini-review, we specifically address the active utilization of microbial respiration processes for the synthesis of novel functional biogenic nanomaterials by the members of the Shewanella genus. This biosynthetic method may provide alternative approaches to produce electrode materials for sustainable energy storage applications.

Abstract Objective: Endoscopic resection(ER) is effective therapy on EGC and which is treated according to the histological diagnosis of forcep biopsy. But sometimes the histological diagnosis of forcep biopsy and post-ER does not match with each other and it might lead to wrong treatment. The aim of this study is to find the frequency of histologic differences between forcep biopsy and post-ER, and to confirm the characteristics of lesions which make errors. Methods: We selected the confirmed cancer cases of 141 patients of 1359 gastric tumor lesions which were treated under the ER in Eulji university hospital from May 2005 to March 2013. They were sorted by the age and sex of patient, location of lesion, present of ulcer and depression to identify the discordance between forcep biopsy and ER. The discordant group was compared with non-cancer-diagnosed controlled group, retrospectively. Results: 70 cases(5.5%) of 1283 cases of “cancer negative” in forceps biopsy were fo䴸nd to be diagnosed cancer on final diagnosis of cancer by post-ER result. In this discordant group showed characteristics of bigger size that are with more frequently in tumor size D15mm(17.9% vs. 31.4%, p=0.03), have depressed lesion(ᄀ 4.3% vs. 41.4%, p

For the past 10 to 13 million years, Antarctic notothenioid fish have undergone extraordinary periods of evolution and have adapted to a cold and highly oxygenated Antarctic marine environment. While these species are considered an attractive model with which to study physiology and evolutionary adaptation, they are poorly characterized at the molecular level, and sequence information is lacking. The transcriptomes of the Antarctic fishes Notothenia coriiceps, Chaenocephalus aceratus, and Pleuragramma antarcticum were obtained by 454 FLX Titanium sequencing of a normalized cDNA library. More than 1,900,000 reads were assembled in a total of 71,539 contigs. Overall, 40% of the contigs were annotated based on similarity to known protein or nucleotide sequences, and more than 50% of the predicted transcripts were validated as full-length or putative full-length cDNAs. These three Antarctic fishes shared 663 genes expressed in the brain and 1,557 genes expressed in the liver. In addition, these cold-adapted fish expressed more Ub-conjugated proteins compared to temperate fish; Ub-conjugated proteins are involved in maintaining proteins in their native state in the cold and thermally stable Antarctic environments. Our transcriptome analysis of Antarctic notothenioid fish provides an archive for future studies in molecular mechanisms of fundamental genetic questions, and can be used in evolution studies comparing other fish.

Histone deacetylases (HDACs) are known to play a central role in the regulation of several cellular properties interlinked with the development and progression of cancer. Recently, HDAC1 has been reported to be overexpressed in hepatocellular carcinoma (HCC), but its biological roles in hepatocarcinogenesis remain to be elucidated. In this study, we demonstrated overexpression of HDAC1 in a subset of human HCCs and liver cancer cell lines. HDAC1 inactivation resulted in regression of tumor cell growth and activation of caspase-independent autophagic cell death, via LC3B-II activation pathway in Hep3B cells. In cell cycle regulation, HDAC1 inactivation selectively induced both p21(WAF1/Cip1) and p27(Kip1) expressions, and simultaneously suppressed the expression of cyclin D1 and CDK2. Consequently, HDAC1 inactivation led to the hypophosphorylation of pRb in G1/S transition, and thereby inactivated E2F/DP1 transcription activity. In addition, we demonstrated that HDAC1 suppresses p21(WAF1/Cip1) transcriptional activity through Sp1-binding sites in the p21(WAF1/Cip1) promoter. Furthermore, sustained suppression of HDAC1 attenuated in vitro colony formation and in vivo tumor growth in a mouse xenograft model. Taken together, we suggest the aberrant regulation of HDAC1 in HCC and its epigenetic regulation of gene transcription of autophagy and cell cycle components. Overexpression of HDAC1 may play a pivotal role through the systemic regulation of mitotic effectors in the development of HCC, providing a particularly relevant potential target in cancer therapy.

Histone deacetylase 2 (HDAC2) is crucial for embryonic development, affects cytokine signaling relevant for immune responses and is often significantly overexpressed in solid tumors; but little is known about its role in human hepatocellular carcinoma (HCC). In this study, we showed that targeted-disruption of HDAC2 resulted in reduction of both tumor cell growth and de novo DNA synthesis in Hep3B cells. We then demonstrated that HDAC2 regulated cell cycle and that disruption of HDAC2 caused G1/S arrest in cell cycle. In G1/S transition, targeted-disruption of HDAC2 selectively induced the expression of p16(INK4A) and p21(WAF1/Cip1), and simultaneously suppressed the expression of cyclin D1, CDK4 and CDK2. Consequently, HDAC2 inhibition led to the down-regulation of E2F/DP1 target genes through a reduction in phosphorylation status of pRb protein. In addition, sustained suppression of HDAC2 attenuated in vitro colony formation and in vivo tumor growth in a mouse xenograft model. Further, we found that HDAC2 suppresses p21(WAF1/Cip1) transcriptional activity via Sp1-binding site enriched proximal region of p21(WAF1/Cip1) promoter. In conclusion, we suggest that the aberrant regulation of HDAC2 may play a pivotal role in the development of HCC through its regulation of cell cycle components at the transcription level providing HDAC2 as a relevant target in liver cancer therapy.

Modulating the electronic asymmetricity of catalysts is an effective method for optimizating the elementary steps of water dissociation and hydrogen adsorption/desorption process for the alkaline hydrogen evolution reaction (HER). Herein, uniform Ru nanoclusters anchored on N doped ultrathin carbon nanosheets (Ru/NC) are synthesized to optimize the asymmetricity electronic properties of supported Ru for efficient HER. It is found that Ru and NC with a large work function difference (횫횽) leading to the formation of stronger asymmetrical charge distributions of Ru that electron-deficient high-valence Ru (Run+) coupling with low-valence Ru (Ru0). Experimental and theoretical studies indicate the Run+ sites lowered the energy barrier for water dissociation and provided enough hydrogen proton to promote the hydrogen spillover from the Run+ to Ru0 sites, and Ru0 sites can enhance H desorption process, thus synergistically enhancing the hydrogen evolution activity. Notably, the Ru/NC catalyst exhibits a high alkaline HER activity (21.9 mV@10 mA cm-2, 29.03 mV dec-1). The role of electronic asymmetricity on supported Ru nanoclusters for the alkaline HER are demonstrated, which will provide guidelines for the rational design of high-efficiency alkaline HER catalysts. [ABSTRACT FROM AUTHOR]