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Supercross-linked polymers are widely used as carbon precursor materials due to their abundant carbon sources and low cost. In this paper, a supercross-linked polymer was prepared by the solvothermal method. The supercross-linked polymer as a precursor and the PPyC-800-A was synthesized by activating this with KOH. The microstructure, structure, and electrochemical performances of porous carbon PPyC-800-A were studied at different of temperature and carbon alkali ratio. According to the results, the porous carbon PPyC-800-1:2 is mainly composed of a stack of spherical particles with a high surface area of 1427.03 m2g−1, an average pore diameter of 2.32 nm, and a high specific capacitance of 217.7 F g−1at a current density of 1.0 A g−1in a 6 M KOH electrolyte. It’s retention rate is 97.58% after 5000 constant current charges and discharges. With a specific capacitance decay rate of 21.91 percent, an energy density of 11.96 Wh kg−1, and a power density of 500.0 W kg−1, the current density rises from 1.0 A g−1to 10.0 A g−1, exhibiting remarkable electrochemical properties, cycling stability, and energy production performance This study contributes experimental ideas to the field of supercross-linked polymer-derived carbon materials and energy storage.

Transfer RNA fragments are proposed to regulate numerous processes in eukaryotes, including translation inhibition, epigenetic inheritance, and cancer. In the bacterium Salmonella entericaserovar Typhimurium, 5′ tRNA halves ending in 2′,3′ cyclic phosphate are proposed to bind the RtcR transcriptional activator, resulting in transcription of an RNA repair operon. However, since 5′ and 3′ tRNA halves can remain base paired after cleavage, the 5′ tRNA halves could potentially bind RtcR as nicked tRNAs. Here we report that nicked tRNAs are ligands for RtcR. By isolating RNA from bacteria under conditions that preserve base pairing, we show that many tRNA halves are in the form of nicked tRNAs. Using a circularly permuted tRNA that mimics a nicked tRNA, we show that nicked tRNA ending in 2′,3′ cyclic phosphate is a better ligand for RtcR than the corresponding 5′ tRNA half. In human cells, we show that some tRNA halves similarly remain base paired as nicked tRNAs following cleavage by anticodon nucleases. Our work supports a role for the RNA repair operon in repairing nicked tRNAs and has implications for the functions proposed for tRNA fragments in eukaryotes.

ABSTRACTThe expression of circRNA_FOXO3 was found to be positively associated with the expression of Forkhead Box O3 (FOXO3), which is targeted and regulated by miR-23a. Polymorphisms in rs12196996 and rs2232365 have been reported in various diseases. In this study, we recruited intensive care unit (ICU)-acquired sepsis patients and grouped them according to their genotypes of rs12196996 and rs2232365. Quantitative real-time PCR was performed to analyze the expression of circRNA_FOXO3, FOXO3 mRNA, and miR-23a. ELISA was carried out to evaluate the abundance of cytokines and luciferase assay was used to explore the inhibitory role of miR-23a on circRNA_FOXO3 and FOXO3. Accordingly, we found that rs12196996 GG and rs2232365 AA were significantly correlated with prolonged survival of ICU-acquired sepsis patients. Rs12196996 GG and rs2232365 AA were also correlated with increased level of miR-23a, IL-10 and decreased level of TNF, IL-2, IFN, IL-6 and IL-1β in the peripheral blood cell samples of patients with ICU-acquired sepsis. The luciferase activity of wild-type (WT) circRNA_FOXO3 and FOXO3 were severely reduced by miR-23a. MiR-23a precursors could effectively suppress the expression of circRNA_FOXO3 and FOXO3 in the cells. Moreover, LPS-induced cell viability loss and dysregulation of cytokines were effectively restored by the knockdown of FOXO3 or circRNA_FOXO3 siRNA in the cells. This study revealed that the minor allele of rs12196996 polymorphism and rs2232365 polymorphism collaboratively contributed to the increased survival and suppressed severity of ICU-acquired sepsis.

Hypercrosslinked polymers HCPs have been widely used as precursors to prepare porous carbon materials because of their highly ordered porous structure and large specific surface area. In this paper, we used a solvothermal method to prepare a hypercrosslinked polymer, and the HCPC-700-A was prepared using an activation method with the hypercrosslinked polymer as the precursor. The effects of different carbon–alkali ratios on the microstructure, composition and electrochemical properties of porous carbon HCP were studied. The results show that the surface of porous carbon HCPC-700-A presents a relatively regular geometric shape, and a large number of pore structures are mainly micro- and mesopores. The specific surface area is 2074.53 m2g−1, and the average pore size is between 1.29 and 1.93 nm. Porous carbon HCPC-700-1:2 has excellent electrochemical performance in 1 M H2SO4, and the specific capacitance is up to 464.4 F g−1 at a current density of 1 A g−1. The specific capacitance decay rate is 29.72% when the current density is increased from 1 A g−1to 8 A g−1. After 5000 cycles, the capacitance retention rate is 91.16% at a current density of 2 A g−1, showing excellent electrochemical performance, good cycle stability and perfect energy storage performance. This research provides new experimental ideas for HCPs in the electrochemical energy storage field.

ABSTRACTBackgroundThere is an unmet need to identify novel mechanism-based prognostic genes associated with hepatocellular carcinoma (HCC) recurrence that can predict patient outcomes and provide therapeutic targets. This study aims to identify potential novel driver genes and mutations in HCC.MethodsSingle nucleotide variations (SNVs) contributing to HCC recurrence were identified using whole-exome sequencing of 5 DNA samples extracted from a single HCC patient with HBV-induced cirrhosis. SNVs were verified in primary HCC (n = 87), recurrent HCC (n = 34), and benign liver disease with cirrhosis tissues (n = 43). A candidate gene was identified, and its association and function in HCC development and recurrence were examined.Results177 SNVs were identified and 70 SNVs were verified. A MPPE1missense mutation on chr18_11897016 was the most frequent mutation (16.5%) in primary and recurrent HCC tissues, occurring with a higher frequency in recurrent HCC than primary HCC or benign liver tumor tissues. The MPPE1mutation was significantly associated with HCC recurrence (P= .003), TNM stage (P= .002), and Child–Pugh classification (P= .039), and was an independent risk factor for HCC recurrence (HR = 1.969; 95%CI = 1.043–3.714, P= .037). Analysis of publically available data deposited in the GEO and TCGA showed MPPE1 expression levels were significantly increased in HCC tumor samples compared to adjacent nontumor tissues. The knockdown of MPPE1 in HCC cell lines significantly inhibited cell proliferation, migration and invasion, induced cell cycle arrest and apoptosis in vitro, and inhibited xenograft tumor growth in nude mice in vivo(P< .05).ConclusionsMPPE1is a novel gene associated with HCC malignancy and recurrence.

A method of hyper-crosslinked polymers-derived carbon compounded with transition metal sulfides was employed in this study for suppressing the severe disadvantage of specific capacitance (SC) decay of transition metal sulfides due to volume variation and to enhancing supercapacitors' performance from the perspectives of power density and energy density, with the aim of addressing the challenge that carbon-based supercapacitors exhibit relatively lower energy density (ED). In this study, PNOC-800-3@NiS composites were well prepared based on the direct carbonization-chemical activation method with hyper-crosslinked polymer (PNO) as the precursor. Subsequently, PNOC-800-3@NiS composites were well prepared based on the hydrothermal approach with thiourea and PNOC-800-3 as the sulfur source and the substrate, separately. The effects exerted by different nickel-sulfur ratios and synthesis temperatures on the composites' electrochemical characteristics were studied. As revealed by the results, the surface area of PNOC-800-3@NiS-2-180 reached 1006.31 m2 g−1, and the pore diameter on average was 1.86 nm at the ratio of nickel to sulfur of 1:2 and the synthesis temperature of 180 °C. In the 6 M KOH electrolyte solution, composites exhibited the SC of 1051.2 F g−1under a current density (CD) of 1 A g−1. With the rising CD in a range between 1 A g−1and 10 A g−1, SC achieved a decay rate of 49.58 %. Under a power density (PD) of 700 W kg−1, a prominent ED was achieved by the assembled asymmetric supercapacitor, which was of 20.98 Wh kg−1. When 5000 cycles of discharging and charging was achieved, the composite PNOC-800-3@NiS-2-180 exhibited a capacitance retention rate of 72.63 %. Furthermore, as indicated by the result, the composite PNOC-800-3@NiS-2-180 exhibited prominent electrochemical characteristics, and can serve as one of the highly suitable electrode materials to be used in supercapacitors.

Zr modified spherical mesostructured cellular silica foams (MCFs) with different Zr contents were successfully synthesized via an incipient wetness impregnation method. The characterization results of FTIR, SEM, and SAXS indicated that zirconium was fabricated into the silicon framework; meanwhile, the parent sphere-like morphology and topological structure were retained. Additionally, BET results showed that the as-synthesized materials possessed ultralarge pore volume (1.56 cm3/g), large pore size (15.9 nm), and high surface area (467 m2/g) when the weight percentage of Zr in the support was 12.6%, demonstrating that MCFs would be an alternative support for hydrotreating catalyst. Furthermore, the corresponding supported NiMo/Zr-MCFs catalysts were well-characterized. It was found that zirconium as an electronic promoter not only facilitated the formation of NiMoO4precursor but also enhanced the redox ability of the catalysts as well as brought Brønsted and Lewis acid sites into MCFs, which were conducive to the hydrodesulfurization (HDS) performance. Then the catalyst activities were evaluated by using FCC diesel as feedstock, in which NiMo/Zr-MCFs-6.9 catalyst (Si/Zr = 20) had the highest hydrodesulfurization (97.3%) and hydrodenitrogenation efficiencies (98.1%); correspondingly, the main reasons could be ascribed to its desirable textural property, suitable redox ability, appropriate dispersion degree of active metals, and moderate acid property.

Investigations of missing proteins (MPs) are being endorsed by many bioanalytical strategies. We proposed that proteogenomics of testis tissue was a feasible approach to identify more MPs because testis tissues have higher gene expression levels. Here we combined proteomics and transcriptomics to survey gene expression in human testis tissues from three post-mortem individuals. Proteins were extracted and separated with glycine- and tricine-SDS-PAGE. A total of 9597 protein groups were identified; of these, 166 protein groups were listed as MPs, including 138 groups (83.1%) with transcriptional evidence. A total of 2948 proteins are designated as MPs, and 5.6% of these were identified in this study. The high incidence of MPs in testis tissue indicates that this is a rich resource for MPs. Functional category analysis revealed that the biological processes that testis MPs are mainly involved in are sexual reproduction and spermatogenesis. Some of the MPs are potentially involved in tumorgenesis in other tissues. Therefore, this proteogenomics analysis of individual testis tissues provides convincing evidence of the discovery of MPs. All mass spectrometry data from this study have been deposited in the ProteomeXchange (data set identifier PXD002179).

The use of serum anti-hepatitis B core antibody (HBc)–positive/hepatitis B surface antigen (HBsAg)-negative liver donors for patients with hepatitis B virus (HBV)–related liver disease (HBRLD) is a promising means of expanding the organ donor pool and does not increase the risk of HBV recurrence. However, whether such donors will compromise the histology of the liver grafts is unclear.

Many bacteria encode an ortholog of the Ro60 autoantigen, a ring-shaped protein that is bound in animal cells to noncoding RNAs (ncRNAs) called Y RNAs. Studies in Deinococcus radioduransrevealed that Y RNA tethers Ro60 to polynucleotide phosphorylase, specializing this exoribonuclease for structured RNA degradation. Although Ro60 orthologs are present in a wide range of bacteria, Y RNAs have been detected in only two species, making it unclear whether these ncRNAs are common Ro60 partners in bacteria. In this study, we report that likely Y RNAs are encoded near Ro60 in >250 bacterial and phage species. By comparing conserved features, we discovered that at least one Y RNA in each species contains a domain resembling tRNA. We show that these RNAs contain nucleotide modifications characteristic of tRNA and are substrates for several enzymes that recognize tRNAs. Our studies confirm the importance of Y RNAs in bacterial physiology and identify a new class of ncRNAs that mimic tRNA.

Non-coding RNAs (ncRNAs) called Y RNAs are abundant components of both animal cells and a variety of bacteria. In all species examined, these ~100 nt RNAs are bound to the Ro 60 kDa (Ro60) autoantigen, a ring-shaped protein that also binds misfolded ncRNAs in some vertebrate nuclei. Although the function of Ro60 RNPs has been mysterious, we recently reported that a bacterial Y RNA tethers Ro60 to the 3′ to 5′ exoribonuclease polynucleotide phosphorylase (PNPase) to form RYPER (Ro60/YRNA/PNPase Exoribonuclease RNP), a new RNA degradation machine. PNPase is a homotrimeric ring that degrades single-stranded RNA, and Y RNA-mediated tethering of Ro60 increases the effectiveness of PNPase in degrading structured RNAs. Single particle electron microscopy of RYPER suggests that RNA threads through the Ro60 ring into the PNPase cavity. Further studies indicate that Y RNAs may also act as gates to regulate entry of RNA substrates into the Ro60 channel. These findings reveal novel functions for Y RNAs and raise questions about how the bacterial findings relate to the roles of these ncRNAs in animal cells. Here we review the literature on Y RNAs, highlighting their close relationship with Ro60 proteins and the hypothesis that these ncRNAs function generally to tether Ro60 rings to diverse RNA-binding proteins.

Objective: The prognostic role of tumor biological markers (biomarkers) in predicting recurrence of hepatocellular carcinoma (HCC) was investigated in this study, the results of which may help to select appropriate candidates for liver transplantation (LT).Methods: Tissue samples from 82 HCC patients with cirrhosis who had undergone LT were immunohistochemically stained with antibodies of anti-CD147, anti-matrix metalloproteinases-2 (MMP-2), MMP-9 and anti-vascular endothelial growth factor (VEGF). Tumor microvessel density (MVD) was evaluated by using CD34. Multivariate Cox regression analysis was performed to identify the relevant prognostic factors.Results: A significant correlation was found between the expression of CD147, VEGF, MMP-2, MMP-9 and MVD-CD34 in HCC. Tumor CD147 expression (P<0.0001), tumor MVD-CD34 (P < 0.0001), MMP-9 in stromal compartment (P=0.0257) and tumor VEGF expression (P=0.0335) were significantly associated with the recurrence in HCC patients after LT. Univariate analysis showed that strong CD147 expression and high MVD-CD34 were significantly associated with poor tumor recurrence-free survival after LT (P < 0.0001). Multivariate analysis indicated that CD147 (P=0.0001), MVD-CD34 (P=0.0118), MMP-2 (P =0.0312) and MMP-9 (P =0.0280) in stromal compartment were all significant predictors in predicting HCC recurrence, while VEGF, MMP-2 and MMP-9 in tumor compartment were not significantly associated with poor prognosis.Conclusions: The tumor biomarkers CD147 and MVD-CD34 are more feasible markers for rational selection of LT candidates with HCC. MMP-9 and MMP-2 expression in stromal compartment, combined with pTNM tumor grade, may be helpful in predicting poor prognosis in HCC patients after LT.

Sm-like (Lsm) proteins function in a variety of RNA-processing events. In yeast, the Lsm2–Lsm8 complex binds and stabilizes the spliceosomal U6 snRNA, whereas the Lsm1–Lsm7 complex functions in mRNA decay. Here we report that a third Lsm complex, consisting of Lsm2–Lsm7 proteins, associates with snR5, a box H/ACA snoRNA that functions to guide site-specific pseudouridylation of rRNA. Experiments in which the binding of Lsm proteins to snR5 was reconstituted in vitro reveal that the 3′ end of snR5 is critical for Lsm protein recognition. Glycerol gradient sedimentation and sequential immunoprecipitation experiments suggest that the Lsm protein-snR5 complex is partly distinct from the complex formed by snR5 RNA with the box H/ACA proteins Gar1p and Nhp2p. Consistent with a separate complex, Lsm proteins are not required for the function of snR5 in pseudouridylation of rRNA. We demonstrate that in addition to their known nuclear and cytoplasmic locations, Lsm proteins are present in nucleoli. Taken together with previous findings that a small fraction of pre-RNase P RNA associates with Lsm2–Lsm7, our experiments suggest that an Lsm2–Lsm7 protein complex resides in nucleoli, contributing to the biogenesis or function of specific snoRNAs.

The liver plays a unique role as a metabolic center of the body, and also performs other important functions such as detoxification and immune response. Here, we establish a cell type-resolved healthy human liver proteome including hepatocytes (HCs), hepatic stellate cells (HSCs), Kupffer cells (KCs), and liver sinusoidal endothelial cells (LSECs) by high-resolution mass spectrometry. Overall, we quantify total 8354 proteins for four cell types and over 6000 proteins for each cell type. Analysis of this data set and regulatory pathway reveals the cellular labor division in the human liver follows the pattern that parenchymal cells make the main components of pathways, but nonparenchymal cells trigger these pathways. Human liver cells show some novel molecular features: HCs maintain KCs and LSECs homeostasis by producing cholesterol and ketone bodies; HSCs participate in xenobiotics metabolism as an agent deliverer; KCs and LSECs mediate immune response through MHC class II–TLRs and MHC class I–TGFβ cascade, respectively; and KCs play a central role in diurnal rhythms regulation through sensing diurnal IGF and temperature flux. Together, this work expands our understandings of liver physiology and provides a useful resource for future analyses of normal and diseased livers.

Many bacteria contain an RNA repair operon, encoding the RtcB RNA ligase and the RtcA RNA cyclase, that is regulated by the RtcR transcriptional activator. Although RtcR contains a divergent version of the CARF (CRISPR-associated Rossman fold) oligonucleotide-binding regulatory domain, both the specific signal that regulates operon expression and the substrates of the encoded enzymes are unknown. We report that tRNA fragments activate operon expression. Using a genetic screen in Salmonella entericaserovar Typhimurium, we find that the operon is expressed in the presence of mutations that cause tRNA fragments to accumulate. RtcA, which converts RNA phosphate ends to 2′, 3′-cyclic phosphate, is also required. Operon expression and tRNA fragment accumulation also occur upon DNA damage. The CARF domain binds 5′ tRNA fragments ending in cyclic phosphate, and RtcR oligomerizes upon binding these ligands, a prerequisite for operon activation. Our studies reveal a signaling pathway involving broken tRNAs and implicate the operon in tRNA repair.

Commensal bacterial orthologs of the human autoantigen Ro60 may trigger cross-reactive T and B cells that initiate and sustain chronic autoimmunity in lupus.

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