IL-21 collaborates with anti-TIGIT to restore NK cell function in chronic HBV infection.

Available therapies for chronic hepatitis B virus (HBV) infection are not satisfying, and interleukin-21 (IL-21) and checkpoint inhibitors are potential therapeutic options. However, the mechanism underlying IL-21 and checkpoint inhibitors in treating chronic HBV infection is unclear. To explore whether IL-21 and checkpoint inhibitors promote HBV clearance by modulating the function of natural killer (NK) cells, we measured the phenotypes and functions of NK cells in chronic HBV-infected patients and healthy controls on mRNA and protein levels. We found that chronic HBV infection disturbed the transcriptome of NK cells, including decreased expression of KLRK1, TIGIT, GZMA, PRF1, and increased expression of CD69. We also observed altered phenotypes and functions of NK cells in chronic HBV-infected patients, characterized by decreased NKG2D expression, increased TIGIT expression and impaired interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α) production. Furthermore, these alterations cannot be restored by telbivudine treatment but can be partially restored by IL-21 and anti-TIGIT stimulation. IL-21 upregulated the expression of activating receptor CD16, CD69, and NKG2D on NK cells, enhanced IFN-γ production, cytolysis, and proliferation of NK cells, while anti-TIGIT promoted IFN-γ production in CD56dim subset exclusively in chronic HBV infected patients. Additionally, IL-21 was indispensable for anti-TIGIT in HBsAg clearance in mice bearing HBV. It enhanced IFN-γ production in splenic NK cells rather than intrahepatic NK cells, indicating a brand-new mechanism of IL-21 in HBV clearance when combined with anti-TIGIT. Overall, our findings contribute to the design of immunotherapy through enhancing the antiviral efficacy of NK cells in chronic HBV infection.

Approaching Theoretical Performances of Electrocatalytic Hydrogen Peroxide Generation by Cobalt-Nitrogen Moieties.

Electrocatalytic oxygen reduction reaction (ORR) has been intensively studied for environmentally benign applications. However, insufficient understanding of ORR 2 e- -pathway mechanism at the atomic level inhibits rational design of catalysts with both high activity and selectivity, causing concerns including catalyst degradation due to Fenton reaction or poor efficiency of H2 O2 electrosynthesis. Herein we show that the generally accepted ORR electrocatalyst design based on a Sabatier volcano plot argument optimises activity but is unable to account for the 2 e- -pathway selectivity. Through electrochemical and operando spectroscopic studies on a series of CoNx /carbon nanotube hybrids, a construction-driven approach based on an extended "dynamic active site saturation" model that aims to create the maximum number of 2 e- ORR sites by directing the secondary ORR electron transfer towards the 2 e- intermediate is proven to be attainable by manipulating O2 hydrogenation kinetics.

Regiocontrolled and Stereoselective Syntheses of Tetrahydrophthalazine Derivatives using Radical Cyclizations.

Tetrahydrophthalazine derivatives have found important applications in pharmaceutical research, but existing synthetic methods are unable to access them regio- and stereoselectively. Here, a new approach is presented that addresses these challenges by utilizing a 6-endo-trig radical cyclization in the key step. The desired tetrahydrophthalazines can be accessed in high yields (55-98 %) and high diastereoselectivities for the trans-product (>95:5) starting either from readily accessible hydrazones, or from the corresponding aldehydes and substituted Boc-hydrazides in a one-pot process. The synthetic versatility of the tetrahydrophthalazine core was demonstrated by its straightforward conversion to dihydro-phthalazines, phthalazines, or pyrazolo dione derivatives. Furthermore, the N-N bond was reduced to afford a new route to 1,4-diamines.

The Importance of Ligand-Induced Backdonation in the Stabilization of Square Planar d10 Nickel π-Complexes.

The electronic nature of Ni π-complexes is underexplored even though these complexes have been widely postulated as intermediates in organometallic chemistry. Herein, the geometric and electronic structure of a series of nickel π-complexes, Ni(dtbpe)(X) (dtbpe=1,2-bis(di-tert-butyl)phosphinoethane; X=alkene or carbonyl containing π-ligands), is probed using a combination of 31 P NMR, Ni K-edge XAS, Ni Kß XES, and DFT calculations. These complexes are best described as square planar d10 complexes with π-backbonding acting as the dominant contributor to M-L bonding to the π-ligand. The degree of backbonding correlates with 2 JPP from NMR and the energy of the Ni 1s→4pz pre-edge in the Ni K-edge XAS data, and is determined by the energy of the π*ip ligand acceptor orbital. Thus, unactivated olefinic ligands tend to be poor π-acids whereas ketones, aldehydes, and esters allow for greater backbonding. However, backbonding is still significant even in cases in which metal contributions are minor. In such cases, backbonding is dominated by charge donation from the diphosphine, which allows for strong backdonation, although the metal centre retains a formal d10 electronic configuration. This ligand-induced backbonding can be formally described as a 3-centre-4-electron (3c-4e) interaction, in which the nickel centre mediates charge transfer from the phosphine σ-donors to the π*ip ligand acceptor orbital. The implications of this bonding motif are described with respect to both structure and reactivity.

Direct experimental evaluation of ligand-induced backbonding in nickel metallacyclic complexes.

The details of ligand-induced backbonding in nickel diphosphine π complexes are explored using nickel L-edge (3d←2p) X-ray absorption spectroscopy as a means of quantifying the degree of backbonding derived from direct Ni 3d donation into the π ligand. It is observed that backbonding into weakly π acidic ligands such as alkenes and arenes is dominated by contributions from the diphosphine ligand via σ-donation, leading to activated metallacycles with a Ni(0) d10 metal centre. With more strongly π acidic ligands, however, metal contributions to backbonding increase substantially leading to a more electron-deficient metal centre that is best described as having a Ni(i) spectroscopic oxidation state.

Polyketides with New Delhi metallo-ß-lactamase 1 inhibitory activity from Penicillium sp.

Three new polyketide compounds (1-3), a new quinolone alkaloid (4), and seven known polyketide derivatives were identified from the cultures of Penicillium sp. I09F 484, a strain isolated from the rhizosphere soil of the plant Picea asperata from Kanas Lake, Xinjiang, China. Their structures were elucidated by extensive spectroscopic data analysis. The absolute configurations of 1 and 4 were established by quantum chemical time-dependent density functional theory electronic circular dichroism calculation and Marfey's method, respectively. Compounds 1 and 2 displayed inhibitory activity against New Delhi metallo-ß-lactamase 1 with IC50 values of 94.9 and 87.9 µM, respectively.

Synthesis and anti-influenza virus activities of a novel class of gastrodin derivatives.

A series of substituted aryl glycoside analogues of gastrodin have been identified as potential anti-influenza agents. The most potent inhibitor 1a exhibited moderate inhibitory activity against the A/Hanfang/359/95(H3N2) and A/FM/1/47(H1N1) strains of the influenza A virus (IC(50) values of 44.40 and 34.45 µM, respectively) and the oseltamivir-null B/Jifang/13/97 strain of influenza B (IC(50) value of 33.01 µM). In this article, multiple doses of compound 1a (80 mg/kg/day, oral administration) were used for the treatment of mice infected with influenza A/FM/1/47-MA (H1N1), and surprisingly we found that compound 1a significantly increased the number of survivors and prolonged the mean survival time. The preliminary studies on the mechanism of antiviral activity showed no interaction between compound 1a and the neuraminidase or the M2 protein. The novel target to overcome drug resistance combined with its good in vivo profile support compound 1a to be a new lead for further development of antiviral agents.

Synthesis and antiviral activity of N-phenylbenzamide derivatives, a novel class of enterovirus 71 inhibitors.

A series of novel N-phenylbenzamide derivatives were synthesized and their anti-EV 71 activities were assayed in vitro. Among the compounds tested, 3-amino-N-(4-bromophenyl)-4-methoxybenzamide (1e) was active against the EV 71 strains tested at low micromolar concentrations, with IC50 values ranging from 5.7 ± 0.8-12 ± 1.2 µM, and its cytotoxicity to Vero cells (TC50 = 620 ± 0.0 µM) was far lower than that of pirodavir (TC50 = 31 ± 2.2 µM). Based on these results, compound 1e is a promising lead compound for the development of anti-EV 71 drugs.

Clinical Implication of E2F Transcription Factor 1 in Hepatocellular Carcinoma Tissues.

Background: To date, the clinical management of advanced hepatocellular carcinoma (HCC) patients remains challenging and the mechanisms of E2F transcription factor 1 (E2F1) underlying HCC are obscure. Materials and Methods: Our study integrated datasets mined from several public databases to comprehensively understand the deregulated expression status of E2F1. Tissue microarrays and immunohistochemistry staining was used to validate E2F1 expression level. The prognostic value of E2F1 was assessed. In-depth subgroup analyses were implemented to compare the differentially expressed levels of E2F1 in HCC patients with various tumor stages. Functional enrichments were used to address the predominant targets of E2F1 and shedding light on their potential roles in HCC. Results: We confirmed the elevated expression of E2F1 in HCC. Subgroup analyses indicated that elevated E2F1 level was independent of various stages in HCC. E2F1 possessed moderate discriminatory capability in differentiating HCC patients from non-HCC controls. Elevated E2F1 correlated with Asian race, tumor classification, neoplasm histologic grade, eastern cancer oncology group, and plasma AFP levels. Furthermore, high E2F1 correlated with poor survival condition and pooled HR signified E2F1 as a risk factor for HCC. Enrichment analysis of differentially expressed genes, coexpressed genes, and putative targets of E2F1 emphasized the importance of cell cycle pathway, where CCNE1 and CCNA2 served as hub genes. Conclusions: We confirmed the upregulation of E2F1 and explored the prognostic value of E2F1 in HCC patients. Two putative targeted genes (CCNE1 and CCNA2) of E2F1 were identified for their potential roles in regulating cell cycle and promote antiapoptotic activity in HCC patients.

Pan-Cancer Analysis, Reveals COVID-19-Related BSG as a Novel Marker for Treatment and Identification of Multiple Human Cancers.

Background: Coronavirus disease 2019 (COVID-19) has been a public threat and healthcare concern caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. During the period of the pandemic of COVID-19, cancer patients should be paid more attention as more severe events are found in cancer patients infected with SARS-CoV-2. Basigin (BSG) is an essential factor for the infection and progression of COVID-19 and tumorigenesis of multiple tumors, which may serve as a novel target for the effective treatment against COVID-19 and multiple human cancers. Methods: A total of 19,020 samples from multiple centers were included in our research for the comprehensive investigation of the differences in BSG expression among human organs, cancer cells, cancer tissues, and normal tissues. Cox regression analysis and Kaplan-Meier curves were utilized to explore the prognosis factor of BSG in cancers. Correlation analyses were used to determine associations of BSG expression with tumor mutational burden, the immune microenvironment, etc. Gene set enrichment analysis was applied to explore the underlying mechanisms of BSG in cancers. Results: Compared with normal tissues, BSG expression was high in 13 types of cancers (cholangiocarcinoma, etc.) and low in colon adenocarcinoma and rectum adenocarcinoma. BSG expression was related to the prognosis of eight cancers (e.g., invasive breast carcinoma) (p < 0.05). The gene also demonstrated a pronounced effect in identifying 12 cancers (cholangiocarcinoma, etc.) from their control samples (AUC >0.7). The BSG expression was associated with DNA methyltransferases, mismatch repair genes, immune infiltration levels, tumor mutational burden, microsatellite instability, neoantigen, and immune checkpoints, suggesting the potential of BSG as an exciting target for cancer treatment. BSG may play its role in several cancers by affecting several signaling pathways such as drug cytochrome metabolism P450 and JAK-STAT. Conclusion: BSG may be a novel biomarker for treating and identifying multiple human cancers.

Construction and Validation of a Novel Prognostic Signature of Idiopathic Pulmonary Fibrosis by Identifying Subtypes Based on Genes Related to 7-Methylguanosine Modification.

Background: Idiopathic pulmonary fibrosis (IPF) is the interstitial lung disease with the highest incidence and mortality. The lack of specific markers results in limited treatment methods for IPF patients. Numerous prognostic signatures represented effective indexes in predicting the survival of patients in various diseases; however, little is investigated on their application in IPF. Methods: This study attempted to explore the clinical markers suitable for IPF by constructing a prognostic signature from the perspective of 7-methylguanosine (m7G). An m7G-related prognostic signature (m7GPS) was established based on the discovery cohort with the LASSO algorithm and was verified by internal and external validation cohorts. The area under the curve (AUC) values were utilized to assess the accuracy of m7GPS in predicting the prognosis of IPF patients and the ability of m7GPS in screening IPF patients. Kaplan-Meier curves and Cox regression analyses were used to identify the relationship of m7GPS with the prognosis of IPF individuals. Enrichment analyses, CIBERSORT algorithm, and weighted gene co-expression network analysis were applied to explore the underlying mechanisms and correlation of m7GPS in IPF. Results: The two m7G regulatory genes can divide IPF into subtypes 1 and 2, and subtype 2 demonstrated a poor prognosis for IPF patients (p < 0.05). For the first time in this field, the m7GPS was constructed. m7GPS made it feasible to predict the 1-5 years survival status of IPF patients (AUC = 0.730-0.971), and it was an independent prognostic risk factor for IPF patients (hazard ratio > 1, p < 0.05). The conspicuous ability of m7GPS to screen IPF patients from the healthy was also revealed by an AUC value of 0.960. The roles of m7GPS in IPF may link to inflammation, immune response, and immune cell levels. Seven genes (CYR61, etc.) were identified as hub genes of m7GPS in IPF. Three drugs (ZM447439-1050, AZD1332-1463, and Ribociclib-1632) were considered sensitive to patients with high m7GPS risk scores. Conclusion: This study developed a novel m7GPS, which is a reliable indicator for predicting the survival status of IPF patients and is identified as an effective marker for prognosis and screening of IPF patients.

Impaired CD8+ T cells in term pregnancy decidua with chronic hepatitis B virus infection.

PROBLEM: Hepatitis B virus (HBV) infection is more likely to develop a state of chronicity in early life, particularly mother-to-child transmission (MTCT) of HBV in the fetus during pregnancy. Till now, little is known about the impact of chronic HBV infection on the immune status of the maternal-fetus interface, and the immune profile of placental lymphocytes in MTCT of HBV is poorly understood. METHOD OF STUDY: Thirteen term pregnant women with chronic HBV infection (HBV-PW) and thirteen normal pregnant women as healthy control (HC-PW) were enrolled. The profile of placental immune cells and paired peripheral blood were analyzed by flow cytometry and immunohistochemistry. RESULTS: Compared with HC-PW, the frequency of CD8+ T cells from the term placenta of HBV-PW was significantly reduced. These cells showed decreased expression of activation molecules CD69 and HLA-DR; thus, decidual CD8+ T cells from HBV-PW demonstrated hypofunctional signature as evidenced by significantly reduced production of IFN-γ, as well as compromised ability of degranulation and proliferation. CONCLUSIONS: These findings supported that hypoactivated decidual CD8+ T cells might possess compromised ability in chronically HBV-infected term pregnant women. Our study provides robust evidence for the necessity and importance of antiviral intervention in HBV-PW to prevent MTCT of HBV.

Direct metal-carbon bonding in symmetric bis(C-H) agostic nickel(i) complexes.

Agostic interactions are examples of σ-type interactions, typically resulting from interactions between C-H σ-bonds with empty transition metal d orbitals. Such interactions often reflect the first step in transition metal-catalysed C-H activation processes and thus are of critical importance in understanding and controlling σ bond activation chemistries. Herein, we report on the unusual electronic structure of linear electron-rich d9 Ni(i) complexes with symmetric bis(C-H) agostic interactions. A combination of Ni K edge and L edge XAS with supporting TD-DFT/DFT calculations reveals an unconventional covalent agostic interaction with limited contributions from the valence Ni 3d orbitals. The agostic interaction is driven via the empty Ni 4p orbitals. The surprisingly strong Ni 4p-derived agostic interaction is dominated by σ contributions with minor π contributions. The resulting ligand-metal donation occurs directly along the C-Ni bond axis, reflecting a novel mode of bis-agostic bonding.

Identifying the Prognostic Risk Factors of Synaptojanin 2 and Its Underlying Perturbations Pathways in Hepatocellular Carcinoma.

Synaptojanin 2 (SYNJ2) regulates cell proliferation and apoptosis via dephosphorylating plasma membrane phosphoinositides. Aim of this study is to first seek the full-scale expression levels and potential emerging roles of SYNJ2 in hepatocellular carcinoma (HCC). We systematically analyzed SYNJ2 mRNA expression and protein levels in HCC tissues based on large-scale data and in-house immunohistochemistry (IHC). The clinical significance and risk factors for SYNJ2-related HCC cases were identified. A nomogram of prognosis was created and its performance was validated by concordance index (C-index) and shown in calibration plots. Based on the identified differentially coexpressed genes (DCGs) of SYNJ2, enriched annotations and potential pathways were predicted, and the protein interacting networks were mapped. Upregulated SYNJ2 in 3,728 HCC and 3,203 non-HCC tissues were verified and in-house IHC showed higher protein levels of SYNJ2 in HCC tissues. Pathologic T stage was identified as a risk factor. Upregulated mRNA levels and mutated SYNJ2 might cause a poorer outcome. The C-index of the nomogram model constructed by SYNJ2 level, age, gender, TNM classification, grade, and stage was evaluated as 0.643 (95%CI = 0.619-0.668) with well-calibrated plots. A total of 2,533 DCGs were extracted and mainly functioned together with SYNJ2 in metabolic pathways. Possible transcriptional axis of CTCF/POLR2A-SYNJ2/INPP5B (transcription factor-target) in metabolic pathways was discovered based on ChIP-seq datasets. In summary, transcriptional regulatory axis CTCF/POLR2A-SYNJ2 might influence SYNJ2 expression levels. Increased SYNJ2 expression level could be utilized for predicting HCC prognosis and potentially accelerates the occurrence and development of HCC via metabolic perturbations pathways.

Upregulation of BIRC5 plays essential role in esophageal squamous cell carcinoma.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers in the world, the detection and prognosis of which are still unsatisfactory. Thus, it is essential to explore the factors that may identify ESCC and evaluate the prognosis of ESCC patients. RESULTS: Both protein and mRNA expression levels of BIRC5 are upregulated in ESCC group rather than non-ESCC group (standardized mean difference > 0). BIRC5 mRNA expression is related to the age, tumor location, lymph node stage and clinical stage of ESCC patients (p < 0.05). BIRC5 expression makes it feasible to distinguish ESCC from non-ESCC (area under the curve > 0.9), and its high expression is related to poor prognosis of ESCC patients (restrictive survival time difference = -0.036, p < 0.05). BIRC5 may play an important role in ESCC by influencing the cell cycle pathway, and CDK1, MAD2L and CDC20 may be the hub genes of this pathway. The transcription factors-MAZ and TFPD1 -are likely to regulate the transcription of BIRC5, which may be one of the factors for the high expression of BIRC5 in ESCC. CONCLUSIONS: The current study shows that upregulation of BIRC5 may have essential clinical value in ESCC, and contributes to the understanding of the pathogenesis of ESCC.

The underlying molecular mechanism and identification of transcription factor markers for laryngeal squamous cell carcinoma.

The screening and treatment of laryngeal squamous cell carcinoma (LSCC) still perplexes clinicians, making it necessary to explore new markers. To this end, this research examined the underlying molecular mechanism of LSCC based on high-throughput datasets (n = 249) from multiple databases. It also identified transcription factors (TFs) independently associated with LSCC prognosis. Through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, differential expression genes of LSCC were deemed relevant to the extracellular matrix and its related structures or pathways, suggesting that the extracellular matrix plays an important role in LSCC. At the same time, several hub genes that may also have important roles in LSCC were identified via protein-protein interaction analysis, including CDC45, TPX2, AURKA, KIF2C, NUF, MUC1, MUC7, MUC4, MUC15, and MUC21. Eight unreported LSCC prognostic TFs - BCAT1, CHD4, FOXA2, GATA6, HNF1A, HOXB13, MAFF, and TCF4 - were screened via Kaplan-Meier curves. Cox analysis determined for the first time that HOXB13 expression and gender were independently associated with LSCC prognosis. Compared to control tissues, elevated expression of HOXB13 was found in LSCC tissues (standardized mean difference = 0.44, 95% confidence interval [0.13-0.76]). HOXB13 expression also makes it feasible to screen LSCC from non-LSCC (area under the curve = 0.77), and HOXB13 may play an essential role in LSCC by regulating HOXB7. In conclusion, HOXB13 may be a novel marker for LSCC clinical screening and treatment.

Clinical significance and molecular mechanism of angiotensin-converting enzyme 2 in hepatocellular carcinoma tissues.

During the pandemic of the coronavirus disease 2019, there exist quite a few studies on angiotensin-converting enzyme 2 (ACE2) and SARS-CoV-2 infection, while little is known about ACE2 in hepatocellular carcinoma (HCC). The detailed mechanism among ACE2 and HCC still remains unclear, which needs to be further investigated. In the current study with a total of 6,926 samples, ACE2 expression was downregulated in HCC compared with non-HCC samples (standardized mean difference = -0.41). With the area under the curve of summary receiver operating characteristic = 0.82, ACE2 expression showed a better ability to differentiate HCC from non-HCC. The mRNA expression of ACE2 was related to the age, alpha-fetoprotein levels and cirrhosis of HCC patients, and it was identified as a protected factor for HCC patients via Kaplan-Meier survival, Cox regression analyses. The potential molecular mechanism of ACE2 may be relevant to catabolic and cell division. In all, decreasing ACE2 expression can be seen in HCC, and its protective role for HCC patients and underlying mechanisms were explored in the study.

Synthesis and antiviral activities of synthetic glutarimide derivatives.

A series of novel glutarimide compounds were synthesized and their antiviral activities were evaluated. The compounds displaying the strongest antiviral activities included 5, 6f, 7e and 9 against coxsackievirus B3 (Cox B3), 10 and 6f against influenza virus A (influenza A) and 7a against herpes simplex virus 2 (HSV-2). However, most of the synthetic glutarimides showed comparatively much weaker activity against influenza A, Cox B3 and HSV-2 than the natural glutarimide compounds tested. Based on the results, it seemed likely that a conjugated system at the ß-substituted moiety provides stronger antiviral activity.

[In vitro anti-influenza virus activity of 10 traditional Chinese medicines].

Influenza virus is a virus causing upper respiratory tract infection disease with high morbidity and mortality. China is considered as an area with high rate of influenza morbidity. Prevention and treatment of influenza currently rely on vaccines and antiviral agents in the world. In addition, traditional Chinese medicines also have been used in clinical for influenza therapy. In vitro anti-influenza virus activities of 10 traditional Chinese medicines were studied by cytopathic effect (CPE). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Guangdong Luohu/219/2006 (H1N1); Yinhuang oral liquid had strong antiviral activity against influenza virus A/Hanfang/359/95 and A/Yuefang/243/72 (H3N2). Qingkailing oral liquid (factory G) had strong antiviral activity against influenza virus A/Jifang/15/90 (H3N2). Qingre Jiedu oral liquid (factory H) had strong antiviral activity against influenza virus A/Jifang/15/90, A/Yuefang/243/72 (H3N2) and virus B.

[In vitro and in vivo anti-influenza virus activity of ribavirin injection].

Ribavirin is a broad-spectrum inhibitor against several unrelated DNA or RNA viruses in vitro and in vivo. In this paper the in vitro and in vivo study of anti-influenza virus activity of ribavirin (RBV) injection had been reported. The in vitro antiviral activity of ribavirin injection against influenza virus A and B was studied by CPE. The in vivo protective action of ribavirin injection against influenza A/FM/1/47(H1N1) mouse adapted strain infected mouse was studied with mouse model. The results showed ribavirin injection has strong inhibitory activity against 7 virus strains tested in vitro. Ribavirin injection could significantly increase virus infected mouse survival rate and survival days and improve lung pathogen and lung index.