An effective two-stage NMBzA-induced rat esophageal tumor model revealing that the FAT-Hippo-YAP1 axis drives the progression of ESCC

Rat model of N-nitrosomethylbenzylamine (NMBzA)-induced esophageal squamous cell carcinoma (ESCC) is routinely used to study ESCC initiation, progression and new therapeutic strategies. However, the model is time-consuming and malignant tumor incidences are low. Here, we report the usage of multi-kinase inhibitor sorafenib as a tumor promoter to establish an efficient two-stage NMBzA-induced rat ESCC carcinogenesis model, resulting in increments of tumor incidences and shortened tumor formation times. By establishing the model and applying whole-genome sequencing, we discover that benign papillomas and malignant ESCCs harbor most of the "driver" events found in rat ESCCs (e.g. recurrent mutations in Ras family, the Hippo and Notch pathways and histone modifier genes) and the mutational landscapes of rat and human ESCCs overlap extensively. We generate tumor cell lines derived from NMBzA-induced papillomas and ESCCs, showing that papilloma cells retain more characteristics of normal epithelial cells than carcinoma cells, especially their exhibitions of normal rat cell karyotypes and inabilities of forming tumors in immunodeficient mice. Three-dimensional (3-D) organoid cultures and single cell RNA sequencing (scRNA-seq) indicate that, when compared to control- and papilloma-organoids, ESCC-organoids display salient abnormalities at tissue and single-cell levels. Multi-omic analyses indicate that NMBzA-induced rat ESCCs are accompanied by progressive hyperactivations of the FAT-Hippo-YAP1 axis and siRNA or inhibitors of YAP1 block the growth of rat ESCCs. Taken together, these studies provide a framework of using an effective rat ESCC model to investigate multilevel functional genomics of ESCC carcinogenesis, which justify targeting YAP1 as a therapeutic strategy for ESCC.

Low-Temperature Oxidation of Methane on Rutile TiO2(110): Identifying the Role of Surface Oxygen Species

Understanding the microkinetic mechanism underlying photocatalytic oxidative methane (CH4) conversion is of significant importance for the successful design of efficient catalysts. Herein, CH4 photooxidation has been systematically investigated on oxidized rutile(R)-TiO2(110) at 60 K. Under 355 nm irradiation, the C-H bond activation of CH4 is accomplished by the hole-trapped dangling OTi- center rather than the hole-trapped Ob- center via the Eley-Rideal reaction pathway, producing movable CH3• radicals. Subsequently, movable CH3• radicals encounter an O/OH species to form CH3O/CH3OH species, which could further dissociate into CH2O under irradiation. However, the majority of the CH3• radical intermediate is ejected into a vacuum, which may induce radical-mediated reactions under ambient conditions. The result not only advances our knowledge about inert C-H bond activation but also provides a deep insight into the mechanism of photocatalytic CH4 conversion, which will be helpful for the successful design of efficient catalysts.

[Expression of neutrophil extracellular traps and phagocytic functions among patients with hepatic alveolar echinococcosis]

OBJECTIVE

To investigate the expression of neutrophil extracellular traps (NETs) and phagocytic function in the peripheral blood of patients with hepatic alveolar echinococcosis (HAE), and to examine their correlations with clinical inflamma tory indicators and liver functions.

METHODS

A total of 50 patients with HAE admitted to Department of Hepatobiliary and Pancreatic Surgery, The Affiliated Hospital of Qinghai University from August 2022 to June 2023 were enrolled, while 50 age- and gender-matched healthy individuals from the Centre for Healthy Examinations of the hospital during the same period served as controls. The levels of NETs markers neutrophil myeloperoxidase (MPO) and neutrophil elastase (NE) were measured using enzyme-linked immunosorbent assay (ELISA). Peripheral blood neutrophils were isolated using density gradient centrifugation, stimulated in vitro using phorbol 12-myristate 13 acetate (PMA), and the levels of MPO and citrullination histone H3 (CitH3) released by neutrophils were quantified using flow cytometry. The phagocytic functions of neutrophils were examined using flow cytometry. In addition, the correlations of MPO and NE levels with clinical inflammatory indicators and liver biochemical indicators were examined using Spearman correlation analysis among HAE patients.

RESULTS

The peripheral blood plasma MPO［(417.15 ± 76.08) ng/mL vs. (255.70 ± 80.84) ng/mL; t = 10.28, P < 0.05］, NE［(23.16 ± 6.75) ng/mL vs. (11.92 ± 3.17) ng/mL; t = 10.65, P < 0.05］and CitH3 levels［(33.93 ± 18.93) ng/mL vs. (19.52 ± 13.89) ng/mL; t = 4.34, P < 0.05］were all significantly higher among HAE patients than among healthy controls, and a lower phagocytosis rate of neutrophils was detected among HAE patients than among healthy controls［(70.85 ± 7.32)% vs. (94.04 ± 3.90)%; t = 20.18, P < 0.05］, and the ability to produce NETs by neutrophils was higher among HAE patients than among healthy controls following in vitro PMA stimulation. Pearson correlation analysis showed that the phagocytosis rate of neutrophils correlated negatively with platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), interleukin-6 (IL-6) level and C-reactive protein (CRP) level (rs = -0.515 to -0.392, all P values < 0.05), and the MPO and NE levels positively correlated with inflammatory markers NLR, PLR, CRP and IL-6 (rs = 0.333 to 0.445, all P values < 0.05) and clinical liver biochemical indicators aspartic transaminase, alanine aminotransferase, direct bilirubin and total bilirubin among HAE patients (rs = 0.290 to 0.628, all P values < 0.001).

CONCLUSIONS

Excessive formation of NETs is found among HAE patients, which affects the phagocytic ability of neutrophils and results in elevated levels of inflammatory indicators. NETs markers may be promising novel biomarkers for early diagnosis, monitoring, and severity assessment of liver disease.

Cerebrospinal fluid drainage and chronic hydrocephalus in aneurysmal subarachnoid hemorrhage patients with intraventricular hemorrhage

Background

Patients with intraventricular hemorrhage (IVH) are at a higher risk of developing hydrocephalus and often require external ventricular drainage or long-term ventriculoperitoneal shunt surgery.

Objective

To investigate whether cerebrospinal fluid drainage in patients with IVH due to aneurysmal subarachnoid hemorrhage (aSAH) reduces the incidence of chronic hydrocephalus.

Method

A retrospective analysis was conducted on patients with aSAH treated at our hospital between January 2020 and December 2022. The first analysis compared patients with and without IVH, while the second analysis compared IVH patients with and without chronic hydrocephalus. The third analysis compared IVH patients who underwent in different drainage methods which is lumbar drainage (LD) or external ventricular drainage (EVD). The primary outcome measure was the incidence of chronic hydrocephalus.

Result

Of the 296 patients hospitalized with aSAH, 108 (36.5%) had IVH, which was associated with a significantly higher incidence of chronic hydrocephalus compared to patients without IVH (49.1% vs. 16.5%, p < 0.001). Multivariate logistic regression analysis showed that IVH was independently associated with the formation of chronic hydrocephalus (OR: 3.530, 95% CI: 1.958-6.362, p < 0.001). Among the 108 IVH patients, 53 (49.1%) developed chronic hydrocephalus. Multivariate logistic regression analysis revealed that the Hunt Hess grade at admission (OR: 3.362, 95% CI: 1.146-9.863, p = 0.027) and postoperative cerebrospinal fluid drainage (OR: 0.110, 95% CI: 0.036-0.336, p < 0.001) were independent risk factors for the development of chronic hydrocephalus in IVH patients. Among all IVH patients who underwent cerebrospinal fluid drainage, 45 (75%) received continuous lumbar puncture drainage, and 15 (25%) received external ventricular drainage. Univariate analysis did not show a statistically significant difference between the two groups in terms of postoperative chronic hydrocephalus (p = 0.283). However, multivariate logistic regression analysis suggested that the drainage methods of LD and EVD might be associated with the development of chronic hydrocephalus.

Conclusion

The presence of IVH increases the risk of chronic hydrocephalus in patients with aSAH, and postoperative cerebrospinal fluid drainage appears to reduce this risk. The specific effects of lumbar puncture drainage and ventricular drainage on the incidence of chronic hydrocephalus require further investigation.

Analysis of the Genetic Model of the Extremely Narrow Channel Shallow Water Delta in DL-A Oilfield, Bohai Bay Basin

In recent years, the oil and gas reserves discovered in shallow water deltas in China have continued to grow. The research on shallow water delta deposition models and depositional genesis is becoming more and more mature. In this latest discovery, a unique type of extremely narrow channel shallow water delta deposit was found at the top of the V oil group in the lower part of the Minghuazhen Formation during the Neogene period at DL-A Oilfield, located in the Bohai Bay Basin. The width of most single channels in this deposit measures between 100 and 200m, which is relatively rare and differs from existing research. To better understand this unique narrow channel shallow water delta deposit, a range of analysis methods were conducted including trace element analysis, major element analysis, grain size analysis, core observation, casting thin section observation, 3D seismic analysis, and other methods. These analyses were used to determine the sedimentary environment and sedimentary genesis of the deposit in the study area. The results show the following: (1) The top of the V oil group in the lower part of Minghuazhen Formation was deposited with a strong oxidizing environment. In the early stage, the climate was dry and cold, and gradually changed to warm and humid in the late stage. (2) Due to the frequent exposure to the surface, obvious weathered surfaces and sedimentary discontinuities were observed on the cores; the particle size analysis shows that the lamina types developed in the study area are clastic-clay laminae and clay-clastic laminae, which are mostly developed in shallow lakes area. (3) Observations of cores and thin sections also indicated that the hydrodynamic conditions frequently changed in the study area, alternating between strong and weak hydrodynamic conditions in a short period due to the alternating occurrence of flood and dry periods during the rainy season. Weak hydrodynamic conditions and slow water flow result in insufficient undercutting and sidecutting of rivers. The alternating occurrence of flood periods and dry periods has led to the development of crevasse splays and frequent river channel diversions, resulting in the inability of long-term stable development of the river channel. Besides, the change of water level has also led to the rebuilding of the river. Therefore, the multiple effects led to the formation of an extremely narrow channel shallow water delta. The accuracy of the sedimentary model is verified by a comparative study of the Shaliu River and Buha River in the modern Qinghai Lake. The new extremely narrow channels deposition model proposed this time further improves the deposition theory. At the same time, the modern depositional characteristics of the Shaliu River and Buha River also reveal the reservoir deposition between channels that cannot be distinguished by seismic data, providing guidance for the development of oil and gas in the study area.

Effect and mechanism of HMG-CoA reductase inhibitor on the improvement of elderly essential hypertension-induced vascular endothelial function impairment based on the JAK/STAT pathway

OBJECTIVE

Our research was designed to figure out the influence and mechanism of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor on the improvement of elderly essential hypertension-induced vascular endothelial function impairment based on the JAK/STAT pathway.

METHODS

Eighty-six elderly patients with essential hypertension were randomized into a control group (oral Amlodipine Besylate Tablets) and an observation group (oral Amlodipine Besylate Tablets + HMG-CoA reductase inhibitor atorvastatin calcium). Patients in both groups were treated with the drug for 12 weeks. Blood pressure, serum levels of inflammatory factors, and vascular endothelial function indicators, and levels of blood lipids were measured. The modeled rats were treated with atorvastatin calcium and a JAK/STAT pathway inhibitor (AG490), and the levels of cardiac function-related indices, left ventricular mass index, lipid levels, serum inflammatory factors and vascular endothelial function-related indices were detected in each group.

RESULTS

HMG-CoA reductase inhibitor improved blood pressure levels, lipid levels, serum inflammatory factor levels and cardiac function in elderly patients with essential hypertension. Both HMG-CoA reductase inhibitor and AG490 improved blood pressure levels, lipid levels, serum inflammatory factor levels and cardiac function in SHR rats. Both HMG-CoA reductase inhibitor and AG490 decreased p-JAK2/JAK2 and p-STAT3/STAT3 expression levels.

CONCLUSION

Our study demonstrates that HMG-CoA reductase inhibitor improves elderly essential hypertension-induced vascular endothelial function impairment by blocking the JAK/STAT pathway.

[Traditional Chinese medicine for treatment of echinococcosis: a review]

Echinococcosis is a zoonotic parasitic disease caused by infection with Echinococcus species. As the drug of first choice for treatment of echinococcosis, albendazole suffers from problems of large doses and remarkable adverse reactions in clinical therapy. Development of novel drugs against echinococcosis is of urgent need. Recently, great advances have been achieved in the research on traditional Chinese medicine for treatment of echinococcosis. This review summarizes the progress of researches on traditional Chinese medicine for treatment of echinococcosis, aiming to provide insights into development of anti-echinococcosis drugs.

Selective nucleophilic α-C alkylation of phenols with alcohols via Ti=Cα intermediate on anatase TiO2 surface

C-C bond forming reaction by alkylation of aryl rings is a main pillar of chemistry in the production of broad portfolios of chemical products. The dominant mechanism proceeds via electrophilic substitution of secondary and tertiary carbocations over acid catalysts, forming multiple aryl alkylation products non-selectively through all secondary and tertiary carbons in the alkyl chains but producing little α-C alkylation products because primary carbocations are poorly stable. Herein, we report that anatase TiO2 (TiO2-A) catalyzes nucleophilic α-C alkylation of phenols with alcohols in high selectivity to simply linear alkylphenols. Experimental and computational studies reveal the formation of Ti=C- bond with the α-carbon of the alkyl group at oxygen vacancies of the TiO2-A surface. The subsequent α-C alkylation by selective substitution of phenol ortho-C-H bond is verified by deuterium exchanged substrate and DFT calculations.

Dinitrogen Activation by Heteronuclear Bimetallic Cluster Anion FeV- in the Gas Phase

Nitrogen activation is a significant but difficult project in the chemical area. Photoelectron spectroscopy (PES) and calculated results are used to investigate the reaction mechanism of the heteronuclear bimetallic cluster FeV^- toward N₂ activation. The results clearly show that N₂ can be fully activated by FeV^- at room temperature, forming the FeV(μ₂-N)₂^- complex with the totally ruptured N≡N bond. Electronic structure analysis reveals that the activation of N₂ by FeV^- is achieved by the electron transfer of bimetallic atoms and electron back-donation to the metal core, which demonstrates that heteronuclear bimetallic anionic clusters are very important to nitrogen activation. This study provides important information for the rational design of synthetic ammonia catalysts.

Capturing Hydrogen Radicals by Neutral Metal Hydroxides

Capturing the hydrogen radical is of central importance in various systems ranging from catalysis to biology to astronomy, but it has been proven to be challenging experimentally because of its high reactivity and short lifetime. Here, neutral MO₃H₄ (M = Sc, Y, La) complexes were characterized by size-specific infrared-vacuum ultraviolet spectroscopy. All these products were determined to be the hydrogen radical adducts in the form of H•M(OH)₃. The results indicate that the addition of the hydrogen radical to the M(OH)₃ complex is both thermodynamically exothermic and kinetically facile in the gas phase. Moreover, the soft collisions in the cluster growth channel with the helium expansion were found to be demanded for the formation of H•M(OH)₃. This work highlights the pivotal roles played by the soft collisions in the formation of hydrogen radical adducts and also opens new avenues toward the design and chemical control of compounds.

[Analysis of enterovirus infection type among acute respiratory tract infection cases in Luohe City, Henan Province from 2017 to 2021]

Objective: To understand the infection status of Enterovirus (EV) in cases of acute respiratory infections (ARIs) in Luohe City, Henan Province from 2017 to 2021, and analyze the prevalence and type composition of EV in ARIs. Methods: From October 2017 to May 2021, pharyngeal swab samples were collected from 1 828 patients with ARIs in Luohe Central Hospital and the clinical epidemiological data of these cases were also collected. EV-positive samples were identified by Quantitative Real-time Polymerase Chain Reaction (qPCR). The 5'-untranslated region (5'UTR) was amplified by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). The results of 5'UTR region were initially typed by Enterovirus Genotyping Tool Version 1.0. Based on the typing results, the full-length of VP1 region was amplified by RT-PCR. The EV typing was identified again by VP1 region. Results: Among 1 828 cases of ARIs, 56.7% (1 036) were males. The median (Q₁, Q₃) age was about 3 (1, 5) years. Patients under 5 years old accounted for 71.6% (1 309 cases). Among all cases, a total of 71 EV-positive samples were identified by qPCR, with a detection rate of 3.88% (71/1 828). The EV detection rates for men and women were 3.28% (34/1 036) and 4.67% (37/792), without statistically significant differences (χ²=2.32, P=0.14). The EV detection rates for 2 to <6 years, 6 months to <2 years, 6 to <10 years, and <6 months were 6.29% (48/763), 3.00% (18/600), 2.52% (4/159), and 1.67% (1/60) (χ²=27.91, P<0.001). The EV detection rate was 0.92% (3/326) in autumn and winter of 2017. The EV detection rates were 1.18% (6/508), 2.47% (12/485) and 8.31% (34/409) in each year from 2018 to 2020, with an increasing trend year by year(χ²_trend=29.76, P<0.001). The main prevalent seasons were summer and autumn. The detection rate in spring of 2021 was 4.00% (4/100). A total of 12 types were identified and classified as CVA2, CVA4, CVA5, CVA6, CVA10, CVB3, CVB5, E5, E11, E30, PV-1, and EV-D68. The types of CVA2, CVA10, CVA6, and CVB3 were the dominant phenotypes. In 59 sample of EV typing, the main clinical manifestation was upper respiratory tract infection (36/59, 61.01%). The dominant types detected in upper respiratory tract infections were CVA10 (10/36, 27.78%), CVA6 (9/36, 25.00%) and CVB3 (8/36, 22.22%). The dominant type detected in lower respiratory tract infections was CVA2 (7/19, 36.84%). Conclusion: In Luohe City, Henan Province from 2017 to 2021, EV infection in ARIs cases has clear seasonal and age-specific patterns, and the dominant types of upper and lower respiratory tract infections are different.

Solvent-mediated precipitating synthesis and optical properties of polyhydrido Cu13 nanoclusters with four vertex-sharing tetrahedrons

Structurally defined metal nanoclusters facilitate mechanism studies and promote functional applications. However, precisely constructing copper nanoclusters remains a long-standing challenge in nanoscience. Developing new efficient synthetic strategies for Cu nanoclusters is highly desirable. Here, we propose a solvent-mediated precipitating synthesis (SMPS) to prepare Cu₁₃H₁₀(SR)₃(PPh₃)₇ nanoclusters (H-SR = 2-chloro-4-fluorobenzenethiol). The obtained Cu₁₃ nanoclusters are high purity and high yield (39.5%, based on Cu atom), proving the superiority of the SMPS method. The Cu₁₃ nanoclusters were comprehensively studied via a series of characterizations. Single crystal X-ray crystallography shows that the Cu₁₃ nanoclusters contain a threefold symmetry axis and the Cu₁₃ kernel is protected by a monolayer of ligands, including PPh₃ and thiolates. Unprecedentedly, the aesthetic Cu₁₃ kernel is composed of four vertex-sharing tetrahedrons, rather than the common icosahedral or cuboctahedral M₁₃. The intramolecular π⋯π interactions between thiolates and PPh₃ on the surface contribute to the stable configuration. Furthermore, electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) revealed the existence of ten hydrides, including four types of hydrides. Density functional theory (DFT) calculations without simplifying the ligands simulated the location of the 10 hydrides in the crystal structure. Additionally, the steady-state ultraviolet-visible absorption and fluorescence spectra of the Cu₁₃ nanoclusters exhibit unique optical absorbance and photoluminescence. The ultrafast relaxation dynamics were also studied via transient absorption spectroscopy, and the three decay components are attributed to the relaxation pathways of internal conversion, structural relaxation and radiative relaxation. This work provides not only a novel SMPS strategy to efficiently synthesize Cu₁₃ nanoclusters, but also a better insight into the structural characteristics and optical properties of the Cu nanoclusters.

Spectroscopic Identification of the Dinitrogen Fixation and Activation by Metal Carbide Cluster Anions PtCn- (n = 4-6)

Nitrogen fixation is confronted with great challenges in the field of chemistry. Herein, we report that single metal carbides PtC_n^- and PtC_nN₂^- (n = 4-6) are indispensable intermediates in the process of nitrogen fixation by mass spectrometry coupled with anionic photoelectron spectroscopy, quantum chemical calculations, and simulated density-of-state spectra. The most stable isomers of these cluster anions are characterized to have linear chain structures. The fixation and activation of dinitrogen are facilitated by the charge transfer from Pt and C_n to N₂. The significance of π back-donation of the 5d orbital of the Pt atom to the antibonding π orbits of N₂ for dinitrogen fixation and activation is discussed in detail. This study not only provides a theoretical basis at the molecular level for the activation of dinitrogen by mononuclear metal carbide clusters but also provides a new paradigm for dinitrogen fixation.

Photocatalytic Oxidative Dehydrogenation of Propane for Selective Propene Production with TiO2

Oxidative dehydrogenation of propane (ODHP) as an exothermic process is a promising method to produce propene (C₃H₆) with lower energy consumption in chemical industry. However, the selectivity of the C₃H₆ product is always poor because of overoxidation. Herein, the ODHP reaction into C₃H₆ on a model rutile(R)-TiO₂(110) surface at low temperature via photocatalysis has been realized successfully. The results illustrate that photocatalytic oxidative dehydrogenation of propane (C₃H₈) into C₃H₆ can occur efficiently on R-TiO₂(110) at 90 K via a stepwise manner, in which the initial C-H cleavage occurs via the hole coupled C-H bond cleavage pathway followed by a radical mediated C-H cleavage to the C₃H₆ product. An exceptional selectivity of ∼90% for C₃H₆ production is achieved at about 13% propane conversion. The mechanistic model constructed in this study not only advances our understanding of C-H bond activation but also provides a new pathway for highly selective ODHP into C₃H₆ under mild conditions.

[Role of type 2 innate lymphoid cells in helminth infections: a review]

Helminth infections may trigger host innate and adaptive immune responses. Group 2 innate lymphoid cells (ILC2) are an important factor involved in type 2 immune responses, and produce a large number of T helper 2 cell (Th2) cytokines following stimulation by interleukin (IL)-25, IL-33 and thymic stromal lymphopoietin (TSLP), which play a critical role in parasite clearance and tissue repair. Following helminth infections, autocrine factors, mast cells, enteric nervous system and Th2 cells have been recently found to be involved in regulation of ILC2. Unraveling the role of ILC2 in immune response against helminth infections is of great value for basic research and drug development. This review summarizes the research progress on ILC2 and its role in helminth infections.

[Predictive value of serum HBV RNA for therapeutic effect of entecavir in patients with chronic hepatitis B]

OBJECTIVE

To investigate the value of HBV RNA for predicting the therapeutic effect of long-term entecavir (ETV) antiviral therapy in patients with chronic hepatitis B (CHB).

METHODS

Serum samples were collected from 59 CHB patients treated with ETV for 96 or 108 months. HBV RNA levels, HBV DNA levels, and serological marker (HBeAg) levels were measured at baseline and 3, 6, 9, 12, 36, 72, and 96 (or 108) months during the therapy.

RESULTS

Although HBV RNA level decreased after 12 and 36 months of ETV antiviral therapy, no significance changes occurred in HBV RNA negative conversion rate (P>0.05). After 72 months of treatment or longer, 33 patients had HBV RNA levels lower than 100 copies/mL, and among them 29 patients had HBV RNA levels lower than the detection limit, and HBV RNA negative conversion rate was statistically significant (P < 0.05). A lower HBV RNA level was associated with a higher HBeAg negative conversion rate (P < 0.05). Age and HBV RNA level were positively correlated with HBeAg negative conversion rate (P < 0.05).

CONCLUSION

Prolonged ETV antiviral therapy results in better clearance of HBV RNA and a higher negative conversion rate in CHB patients. The length of antiviral therapy and age are positively correlated with the negative conversion rate of HBV RNA, and earlier administration of the antiviral treatment achieves better therapeutic effect. Serum HBV RNA level can be used as an indicator for predicting conversion to negative HBeAg in CHB patients receiving ETV therapy.

The Role of Redox-Inactive Metals in Modulating the Redox Potential of the Mn4CaO4 Model Complex

Photosynthetic oxygen-evolving center (OEC), the "engine of life", is a unique Mn₄CaO₅ cluster catalyzing the water oxidation. The role of redox-inactive component Ca²⁺, which can only be functionally replaced by Sr²⁺ in a biological environment, has been under debate for a long time. Recently, its modulating effect on the redox potential of native OEC and artificial structural OEC model complex has received great attention, and linear relationship between the potential and the Lewis acidity of the redox-inactive metal has been proposed for the MMn₃O₄ model complex. In this work, the modulating effect has been studied in detail using the Mn₄CaO₄ model complex, which is the closest structural model to OEC to date and has a similar redox potential at the S₁-S₂ transition. We found the redox-inactive metal only has a weak modulating effect on the potential, which is comparable in strength to that of the ligand environments. Meanwhile, the net charge of the complex, which could be changed along with the redox-inactive metal, has a high impact on the potential and can be unified by protonation, deprotonation, or ligand modification. Although the modulating effect of the redox-inactive metal is not very strong, the linear relationship between the potential and the Lewis acidity is still valid for Mn₄MO₄ complexes. Our results of strong modulating effects for net charge and weak modulating effects for redox-inactive metal fit with the previous experimental observations on Mn₄MO₄ (M = Ca²⁺, Y³⁺, and Gd³⁺) model complexes, and suggest that Ca²⁺ can be structurally and electrochemically replaced with other metal cations, together with proper ligand modifications.

Aerosol mass spectrometry of neutral species based on a tunable vacuum ultraviolet free electron laser

A vacuum ultraviolet free electron laser (VUV-FEL) photoionization aerosol mass spectrometer (AMS) has been developed for online measurement of neutral compounds in laboratory environments. The aerosol apparatus is mainly composed of a smog chamber and a reflectron time-of-flight mass spectrometer (TOF-MS). The indoor smog chamber had a 2 m³ fluorinated ethylene propylene film reactor placed in a temperature- and humidity-controlled room, which was used to generate the aerosols. The aerosols were sampled via an inlet system consisting of a 100 μm orifice nozzle and aerodynamic lenses. The application of this VUV-FEL AMS to the α-pinene ozonolysis under different concentrations reveals two new compounds, for which the formation mechanisms are proposed. The present findings contribute to the mechanistic understanding of the α-pinene ozonolysis in the neighborhood of emission origins of α-pinene. The VUV-FEL AMS method has the potential for chemical analysis of neutral aerosol species during the new particle formation processes.

[Progress in the study of antiviral activity of cepharanthine against SARS-CoV-2]

As a member of the dibenzyl isoquinoline alkaloid family, cepharathine is an alkaloid from the traditional Chinese medicine cepharathine, which is mainly used for treatment of leukopenia and other diseases. Recent studies of the inhibitory effect of cepharathine against SARS-CoV-2 have attracted widespread attention and aroused heated discussion. As the original discoverer of the anti-SARS-CoV-2 activity of cepharanthine, here we briefly summarize the discovery of cepharanthine and review important progress in relevant studies concerning the discovery and validation of anti-SARS-CoV-2 activity of cepharathine, its antiviral mechanisms and clinical trials of its applications in COVID-19 therapy.

Spectroscopic Characterization of the Synergistic Mechanism of Ruthenium-Lithium Hydrides for Dinitrogen Cleavage

Elucidating the role of alkali/alkaline earth metal hydrides in dinitrogen activation remains an important and challenging goal for spectroscopic studies of bulk systems, because their spectral signatures are often masked by the collective effects. Herein, mass-selected photoelectron velocity-map imaging spectroscopic and quantum chemical calculation techniques are utilized to explore the promotion mechanism of LiH in the Ru-based catalysts toward N₂ activation. The RuHN₂^- anion is determined to be a N₂-tagged complex. In contrast, the RuHN₂(LiH)_n^- (n = 1 and 2) anions are characterized to have N≡N bond-cleaved ring structures. These observations indicate that the complexation of LiH to RuH^- significantly facilitates N≡N bond cleavage. Theoretical analyses show that the synergy between Ru and LiH efficiently lowers the energy barrier of N≡N bond cleavage. These findings clarify the pivotal roles played by the LiH species in the transition metal catalysts for N₂ activation and have important practical implications for the prospective design of high-performance catalysts via metal tuning strategies.

A compact x-ray diffraction system for dynamic compression experiments on pulsed-power generators

Pulsed-power generators can produce well-controlled continuous ramp compression of condensed matter for high-pressure equation-of-state studies using the magnetic loading technique. X-ray diffraction (XRD) data from dynamically compressed samples provide direct measurements of the elastic compression of the crystal lattice, onset of plastic flow, strength-strain rate dependence, structural phase transitions, and density of crystal defects, such as dislocations. Here, we present a cost-effective, compact, pulsed x-ray source for XRD measurements on pulsed-power-driven ramp-loaded samples. This combination of magnetically driven ramp compression of materials with a single, short-pulse XRD diagnostic will be a powerful capability for the dynamic materials' community to investigate in situ dynamic phase transitions critical to equation of states. We present results using this new diagnostic to evaluate lattice compression in Zr and Al and to capture signatures of phase transitions in CdS.

The expression of PHOX2B in bone marrow and peripheral blood predicts adverse clinical outcome in non-high-risk neuroblastoma

Paired-like homeobox 2B (PHOX2B) is a highly sensitive and specific biomarker for diagnosing neuroblastoma, as well as detecting minimal residual disease in neuroblastoma. The clinical significance of PHOX2B expression in bone marrow (BM) and peripheral blood (PB) samples of newly diagnosed patients with very low-, low- and intermediate-risk neuroblastoma remains unknown, to the best of our knowledge. The expression level of PHOX2B in paired BM and PB samples of patients with newly diagnosed neuroblastoma was validated using reverse transcription-quantitative polymerase chain reaction (RTqPCR). Among the 132 patients, 26 exhibited a positive PHOX2B expression BM (19.7%) and 11 in PB (8.3%) samples. PHOX2B was highly expressed in BM and PB samples from patients aged <18 months, with International Neuroblastoma Risk Group Staging System stages M and MS, 1p loss of heterozygosity, and high levels of lactate dehydrogenase, serum ferritin and neuron-specific enolase (p < 0.05). In all eligible patients, the 2-year event-free survival (EFS) and overall survival (OS) rates were 94.7 ± 2.0% and 97.7 ± 1.3%, respectively. However, the 2-year EFS rates were significantly decreased to 76.9 ± 8.3% and 63.6 ± 14.5% in patients with a positive PHOX2B expression in BM and PB samples, respectively (p < 0.05). Similarly, the 2-year OS rates were also decreased to 88.5 ± 6.3% and 81.8 ± 11.6% in patients with a positive PHOX2B expression in BM and PB samples, respectively (p < 0.05). In conclusion, a positive PHOX2B expression in BM and PB samples at diagnosis had a strong adverse prognostic effect on patients with non-high-risk neuroblastoma.

Hydrogen Production on Pt/TiO2: Synergistic Catalysis between Pt Clusters and Interfacial Adsorbates

Understanding the mechanism of hydrogen (H₂) formation from the conversion of water (H₂O) and renewables on TiO₂ surfaces with cocatalysts via either photocatalysis or other catalytic processes is of significant importance to the successful design of efficient catalysts. Herein, we have investigated H₂ production from H₂O, CH₃OH, and C₂H₅OH on a Pt cluster covered rutile (R)-TiO₂(110) surface (Pt_clut/R-TiO₂(110)) to address the mechanism of H₂ production. Experimental results demonstrate that surface adsorbates not only help H atom diffusion on Pt_clut/R-TiO₂(110) but also take part in H₂ production directly. Further density functional theory (DFT) calculations suggest that H₂ production on Pt_clut/R-TiO₂(110) occurs via a synergistic catalysis process between Pt clusters and interfacial adsorbates rather than a recombination reaction of H atoms on Pt clusters. This work provides new insight into H₂ production from H₂O and renewables with Pt/TiO₂ catalysts, which may be applicable to H₂ production on other Pt cluster deposited metal oxide catalysts.

Ligand-Induced Tuning of the Electronic Structure of Rhombus Tetraboron Cluster

A neutral boron carbonyl complex B₄ (CO)₃ is generated in the gas phase and is characterized by infrared plus vacuum ultraviolet (IR+VUV) two-color ionization spectroscopy and quantum chemical calculations. The complex is identified to have a planar C_2v structure with three CO ligands terminally coordinated to a rhombus B₄ core. It has a closed-shell singlet ground state that correlates to an excited state of B₄ . Bonding analyses on B₄ (CO)₃ as well as the previously reported B₄ and B₄ (CO)₂ indicate that the electronic structure of rhombus tetraboron cluster changes from a close-shell singlet to an open-shell singlet in B₄ (CO)₂ and to a close-shell singlet in B₄ (CO)₃ , demonstrating that the electronic structures of boron clusters can be effectively tuned via sequential CO ligand coordination.

[Analysis on incidence trend of liver cancer in China, 2005-2016]

Objective: To understand the incidence trend of liver cancer in China from 2005 to 2016, and explore the correlation between the incidence trend of liver cancer and the incidence trend of hepatitis B. Methods: The incidence data of liver cancer in China from 2005 to 2016 were collected from the Annual Report of Cancer Registry in China. The incidence data of hepatitis B were collected from China Public Health Science Data Center. World standardized incidence rate (WSR) was calculated according to the World Segi's population. Joinpoint regression model was used to analyze the trend of WSR of liver cancer [measured by average annual percentage change (AAPC)]. The age-period-cohort model was fitted to analyze the age, period and cohort effects in people aged 20- years and above. Pearson correlation coefficient was used to explore the correlation between the incidence of liver cancer and the incidence of hepatitis B. Results: The crude incidence of liver cancer in China showed a trend of first increase before 2009 and then relatively stable. The world standardized morbidity rate of liver cancer in China decreased from 19.11 per 100 000 in 2005 to 17.74 per 100 000 in 2016 (AAPC=-0.5%, 95%CI: -1.3%-0.3%, P=0.240). The incidence of liver cancer in male decreased significantly (AAPC=-1.0%, 95%CI: -1.5%--0.5%, P=0.001). The incidence of liver cancer in women increased from 2005 to 2010 [annual percentage change (APC)=1.7%, 95%CI: -0.1%-3.4%, P=0.059] but showed a significant decrease trend from 2010 to 2016 (APC=-1.6%, 95%CI: -2.3%--1.0%, P=0.001). From 2005 to 2016, the incidence of liver cancer showed a decreasing trend in urban areas (AAPC=-0.3%, 95%CI: -0.8%-0.3%, P=0.316) and rural areas (AAPC=-3.9%, 95%CI: -4.4%--3.3%, P<0.001). Risk for liver cancer increased with age, while the period effect showed a trend of first increase then decrease and cohort effect showed a decrease trend. The morbidity rates of both hepatitis B and liver cancer showed decrease trends from 2009 to 2016, and there was a significant correlation (r=0.71, 95%CI: 0.01-0.94, P=0.048). Conclusions: From 2005 to 2016, the morbidity rate of liver cancer in China showed a decrease trend, and there were significant gender and urban-rural area specific differences. Age effect had a great impact on the risk for liver cancer. With the progress of population aging in China, liver cancer is still a public health problem, to which close attention needs to be paid.

Isoelectronic IrC3-, PtC3, and AuC3+ Clusters Featuring the Structural and Bonding Resemblance to OC3

The IrC₃^- and PtC₃^- anions generated by laser vaporization were identified and characterized by gas-phase photoelectron spectroscopy and quantum-chemical calculations. The straight-chain structures with an MCCC (M = metal; C = carbon) connectivity are found for the isoelectronic IrC₃^-, PtC₃, and AuC₃⁺ clusters. Further elaborate analyses manifest the strikingly structural and bonding similarities between MC₃^-/0/+ clusters and OC₃ revealed. This finding has broadened the notion of autogenic isolobality to the gas-phase clusters that contain Ir^-, Pt, Au⁺, and C centers.

[Effects of N-trimethyl chitosan-recombinant tissue factor pathway inhibitor complex on avulsion flap with roll compaction in rat]

Objective: To investigate the effect of N-trimethyl chitosan-recombinant tissue factor pathway inhibitor (rTFPI) complex on avulsion flap with roll compaction in rat. Methods: The experimental methods were adopted. The N-trimethyl chitosan-rTFPI complex solution was prepared by ion cross-linking method. The morphology of the complex was observed by scanning electron microscope, and its diameter was measured. The encapsulation rate of rTFPI in the complex and drug loading rate of the complex was determined and calculated by enzyme-linked immunosorbent assay (ELISA) method (n=3). The concentration of rTFPI in the solution at 0, 10, 30, 45, 60, 90, 120, 240 minutes of storage was measured by ELISA method to observe the release of rTFPI, and its half-life was calculated (n=3). Twenty-four 6-week-old male Sprague-Dawley rats were divided into phosphate buffered saline (PBS) group, N-trimethyl chitosan alone group, rTFPI alone group, and N-trimethyl chitosan-rTFPI group according to the random number table, with 6 rats in each group. The avulsion flaps with roll compaction were prepared on the backs of rats with pedicles located on the line of the bilateral iliac spine and lifted from the surface of the muscle membrane. One injection of corresponding reagents was carried out immediately after in-situ suture and on post operation day (POD) 1, 2, and 3. General changes of the flap were observed on POD 1, 3, and 7. On POD 7, the survival area of the flap was measured and the survival rate of the flap was calculated; the flaps were divided into pedicle, proximal, middle, and distal segments, and the blood perfusion in the proximal, middle, and distal segment tissue of the flap was detected by the laser speckle blood flow imager; tissue samples in the middle of the flap were cut and stained with hematoxylin and eosin to observe the changes in tissue structure and the infiltration of inflammatory cells, and the numbers of embolized blood vessels and new blood vessels per 100 times visual field were counted. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: The N-trimethyl chitosan-rTFPI complex had an irregular spherical structure with a diameter of 150-200 nm. The encapsulation rate of rTFPI in the complex and drug loading rate of the complex were (88.7±2.1)% and (2.83±0.09)%, respectively. The concentration of rTFPI in the solution of the N-trimethyl chitosan-rTFPI complex gradually increased with prolonged storage time, and the release was basically stable at 90 min, with half-life of (651±36) min. On POD 1, the distal parts of flaps of rats in N-trimethyl chitosan alone group darkened significantly. On POD 3, scabs and necrosis were relatively mild on the distal segment of the flaps of rats in rTFPI alone group and N-trimethyl chitosan-rTFPI group as compared with those of the other two groups. On POD 7, the necrosis boundaries of the flaps of rats in each group were clear. On POD 7, the flap survival rates of rats in rTFPI alone group and N-trimethyl chitosan-rTFPI group were (63±7)% and (73±5)%, respectively, which were significantly higher than (41±3)% in PBS group and (52±7)% in N-trimethyl chitosan alone group. Moreover, the flap survival rate of rats in N-trimethyl chitosan-rTFPI group was significantly higher than that in rTFPI alone group (P<0.05). On POD 7, the flaps of rats in each group had blood perfusion; the blood perfusion values in the proximal segment tissue of the rat flaps in N-trimethyl chitosan alone group and the blood perfusion values in the proximal, middle, and distal segment tissue of the rat flaps in rTFPI alone group and N-trimethyl chitosan-rTFPI group were significantly higher than those in PBS group (P<0.05 or P<0.01); the blood perfusion values in the distal segment tissue of the rat flaps in rTFPI alone group and the blood perfusion values in the middle and distal segment tissue of the rat flaps in N-trimethyl chitosan-rTFPI group were significantly higher than those in N-trimethyl chitosan alone group (P<0.05 or P<0.01); the blood perfusion value in the middle segment tissue of the rat flaps in N-trimethyl chitosan-rTFPI group was significantly higher than that in rTFPI alone group (P<0.01). On POD 7, inflammatory cells infiltrated more and cell edema was obvious in the middle segment tissue of the rat flaps in PBS group and N-trimethyl chitosan alone group. Compared with those of the previous two groups, the inflammation degrees in the middle segment tissue of the rat flaps in rTFPI alone group and N-trimethyl chitosan-rTFPI group were significantly milder, the number of embolized blood vessels was significantly decreased (P<0.05 or P<0.01), and the number of new blood vessels was significantly increased (P<0.05 or P<0.01). Compared with that of rTFPI alone group, the number of new blood vessels in the middle segment tissue of the rat flaps in N-trimethyl chitosan-rTFPI group increased significantly (P<0.05). Conclusions: The effect of sustained release of rTFPI can be achieved by loading rTFPI with N-trimethyl chitosan. Compared with rTFPI alone, the N-trimethyl chitosan-rTFPI complex can further improve the blood perfusion of the avulsion flaps with roll compaction in rat and improve the survival rate of the flap.

Divide-and-link peptide docking: a fragment-based peptide docking protocol

Protein-peptide interactions are crucial for various important cellular regulations, and are also a basis for understanding protein-protein interactions, protein folding and peptide drug design. Due to the limited structural data obtained using experimental methods, it is necessary to predict protein-peptide interaction modes using computational methods. In the present work, we designed a fragment-based docking protocol, Divide-and-Link Peptide Docking (DLPepDock), to predict protein-peptide binding modes. This protocol contains the following steps: dividing the peptide into fragments and separately docking the fragments using a third-party small molecular docking tool, linking the docked fragmental poses to form the whole peptide conformations via fragmental coordinate transformation using our in-house program, removing unreasonable poses according to several geometrical filters, extracting representative conformations after clustering for further minimization using the steepest descent and conjugation gradient methods based on a full-atom molecular force field and finally scoring using the MM/PBSA binding energy calculation implemented in Amber. When tested on the LEADS-PEP benchmark data set of 26 diverse complexes with peptides of 6-12 residues, FlexPepDock ab initio and AutoDock CrankPep achieved superior results. DLPepDock performed better than the other 15 docking protocols implemented in nine docking programs (HPepDock, DockThor, rDock, Glide, LeDock, AutoDock, AutoDock Vina, Surflex, and GOLD). The Linux scripts to call the third-party tools and run all the calculations.

[Urine proteomics signatures associated with alcohol drinking among residents attending the National Upper Gastrointestinal Cancer Early Detection Program in Linqu, Shandong province]

The liquid chromatography tandem mass spectrometry was used to detect the urinary proteomics of 223 residents aged 40-69 years old who participated in the National Upper Gastrointestinal Cancer Early Detection Program in Linqu County, Shandong Province from November 22 to December 7, 2018, and analyze the alcohol consumption related proteomic profiles and individual urinary protein. There were significant differences in urinary protein profiles between alcohol consumption group and non-alcohol consumption group. The expression of 26 urinary proteins was up-regulated and 20 urinary proteins were down-regulated in alcohol consumption group (P<0.05). The differentially expressed proteins had enzyme inhibitor activity and phospholipid binding function, and mainly enriched in pathways involving proximal tubule bicarbonate regeneration, complement and coagulation cascade, and cholesterol metabolism. The protein expressions of complement factor I (CFI), angiotensin converting enzyme 2 (ACE2) and protein C inhibitor (SERPINA5) were positively correlated with daily alcohol consumption.

Aspirin enhances the therapeutic efficacy of cisplatin in oesophageal squamous cell carcinoma by inhibition of putative cancer stem cells

BACKGROUND

Cancer stem cells (CSCs) are related to the patient's prognosis, recurrence and therapy resistance in oesophageal squamous cell carcinoma (ESCC). Although increasing evidence suggests that aspirin (acetylsalicylic acid, ASA) could lower the incidence and improve the prognosis of ESCC, the mechanism(s) remains to be fully understood.

METHODS

We investigated the role of ASA in chemotherapy/chemoprevention in human ESCC cell lines and an N-nitrosomethylbenzylamine-induced rat ESCC carcinogenesis model. The effects of combined treatment with ASA/cisplatin on ESCC cell lines were examined in vitro and in vivo. Sphere-forming cells enriched with putative CSCs (pCSCs) were used to investigate the effect of ASA in CSCs. Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) was performed to determine the alterations in chromatin accessibility caused by ASA in ESCC cells.

RESULTS

ASA inhibits the CSC properties and enhances cisplatin treatment in human ESCC cells. ATAC-seq indicates that ASA treatment results in remarkable epigenetic alterations on chromatin in ESCC cells, especially their pCSCs, through the modification of histone acetylation levels. The epigenetic changes activate Bim expression and promote cell death in CSCs of ESCC. Furthermore, ASA prevents the carcinogenesis of NMBzA-induced ESCC in the rat model.

CONCLUSIONS

ASA could be a potential chemotherapeutic adjuvant and chemopreventive drug for ESCC treatment.

[Transepidermal water loss of scar skin in three types of scar patients and its correlation with scar severity]

Objective: To study the transepidermal water loss (TEWL) of scar skin in patients with superficial scars, hypertrophic scars, and atrophic scars, and to explore the correlation between TEWL and scar severity. Methods: A retrospective observational study was conducted. From February 2017 to February 2019, 120 scar patients who met the inclusion criteria were admitted to the General Hospital of Jilin Chemical Industry Group, including 78 males and 42 females, aged (35±14) years. According to the diagnosis on admission, there were 40 cases of superficial scar patients, 40 cases of hypertrophic scar patients, and 40 cases of atrophic scar patients. On admission, the Vancouver Scar Scale (VSS) was used to score the scar of each patient; the TEWL of scar skin and normal skin 1 cm from the edge of scar or the same site of the healthy side (hereinafter referred to as normal skin) of each patient was measured by water loss tester, and the difference value of TEWL between scar skin and normal skin (hereinafter referred to as the TEWL difference) was calculated. Data were statistically analyzed with chi-square test, Kruskal-Wallis rank sum test, paired sample t test, one-way analysis of variance, and Dunnett-t test for comparison, and the correlation between the difference value of TEWL and scar VSS score was analyzed with univariate linear regression analysis. Results: On admission, the scar VSS score of superficial scar patients was significantly lower than that of hypertrophic scar or atrophic scar patients (t=4.403, 4.768, P<0.01), and the scar VSS score of atrophic scar patients was significantly lower than that of hypertrophic scar patients (t=4.185, P<0.01). On admission, the TEWL of scar skin of superficial scar, hypertrophic scar, and atrophic scar patients were (18±4), (20±4), and (20±5) g·m^-2·h^-1 respectively, significantly higher than (12±3), (12±3), and (14±4) g·m^-2·h^-1 of normal skin (t=6.889, 10.221, 5.870, P<0.01). The difference values of TEWL of superficial scar, hypertrophic scar, and atrophic scar patients were (5.9±1.7), (8.1±1.7), and (6.4±2.1) g·m^-2·h^-1 respectively. In comparison among different types of scar patients, only the TEWL difference of hypertrophic scar patients was significantly higher than that of superficial scar patients (t=6.975, P<0.05). The TEWL difference and the scar VSS score in patients with superficial scars, hypertrophic scars, and atrophic scars were significantly positively correlated (r=0.805, 0.872, 0.826, P<0.01). Conclusions: The TEWL of scar skin in patients with superficial scars, hypertrophic scars, and atrophic scars is increased compared with normal skin, and the degree of increase was positively correlated with the severity of scars.

[PI3K/Akt signaling pathway mediates the protective effect of endomorphin-1 postconditioning against myocardial ischemia-reperfusion injury in rats]

OBJECTIVE

To investigate the role of PI3K/Akt signaling pathway in mediating the protective effect of endomorphin-1 against myocardial ischemia-reperfusion (IR) injury.

OBJECTIVE

Fifty SD male rats were randomly divided into sham operation group, myocardial IR group, endomorphin-1 post-treatment group (EM50 group), endomorphin-1+wortmannin (a PI3K/Akt signaling pathway inhibitor) treatment group (EM50+Wort group), and wortmannin treatment group (Wort group). Rat models of myocardial IR injury were established by ligation of the left anterior descending coronary artery for 30 min followed by reperfusion for 120 min. The heart rate and mean arterial pressure were monitored during the experiment. Plasma levels of LDH, CK-MB, cTnI, IL-6, TNF-α, SOD and MDA were measured after reperfusion. The mRNA expression of Bax and Bcl-2 was detected using RT-PCR, and the expression of apoptosis-related protein cleaved caspase-3, phosphorylated Akt protein and total Akt protein in myocardial tissue was detected using Western blotting.

OBJECTIVE

Myocardial IR injury significantly decreased heart rate and blood pressure of the rats in comparison with the sham operation (P < 0.05). Compared with those in the IR group, the rats in EM50 group showed significantly increased heart rate and blood pressure (P < 0.05) with decreased plasma LDH, CK-MB, cTnI, IL-6, TNF-α and MDA levels (P < 0.05), increased SOD activity (P < 0.05), increased expression of p-Akt protein and Bcl-2 mRNA (P < 0.05), and decreased expression of Bax mRNA and cleaved caspase-3 protein (P < 0.05). In EM50+Wort group, the heart rate and blood pressure were significantly lowered (P < 0.05), plasma LDH, CK-MB, cTnI, IL-6, TNF-α and MDA levels increased (P < 0.05), SOD activity decreased (P < 0.05), the expression of p-Akt protein and Bcl-2 mRNA was reduced (P < 0.05), and the expression of Bax mRNA and cleaved caspase-3 protein increased (P < 0.05) as compared with those in EM50 group.

OBJECTIVE

EM-1 postconditioning can regulate cardiac myocyte apoptosis and reduce myocardial IR injury in rats. The PI3K/Akt signaling pathway may play a role in mediating the myocardial protective effects of EM-1 postconditioning.

POS0651 CLINICAL AND FUNCTIONAL RESPONSE TO TOFACITINIB IN PATIENTS WITH RHEUMATOID ARTHRITIS: PROBABILITY PLOT ANALYSIS OF RESULTS FROM A 48-WEEK PHASE 3b/4 METHOTREXATE WITHDRAWAL STUDY

Background:

The Phase 3b/4 study ORAL Shift (NCT02831855) demonstrated sustained efficacy/safety of tofacitinib modified-release 11 mg QD following MTX withdrawal, that was non-inferior to continued tofacitinib + MTX use, in patients (pts) with moderate to severe RA who achieved LDA with tofacitinib + MTX at Week (W)24.1

Objectives:

To assess differences and similarities in clinical/functional responses in pts receiving tofacitinib ± MTX in ORAL Shift.

Methods:

In ORAL Shift, pts received open-label tofacitinib + MTX to W24; at W24, pts who achieved CDAI LDA were randomised to receive tofacitinib + MTX or tofacitinib + placebo (PBO) from W24–48. In this post hoc analysis, clinical efficacy endpoints were ACR-N (minimum % change from baseline [BL; Δ] at W48 achieved by each pt in 3 efficacy measures), ΔDAS28-4(ESR), and DAS28-4(ESR) remission/LDA (scores ≤3.2) and moderate/high disease activity (scores >3.2). Functional efficacy endpoints were ΔHAQ-DI and HAQ-DI clinically relevant functional progression (CRFP) status at W48, defined as failure to achieve improvement in HAQ-DI ≥ minimum clinically important difference (MCID; ≥0.22 decrease from BL in HAQ-DI). Thus, CRFP was defined as <0.22 decrease, no change or increase from BL in HAQ-DI at W48. All efficacy endpoints were summarised descriptively. Cumulative probability plots of ACR-N and ΔHAQ-DI were produced. Median of mean CRP values from BL–W24 and >W24–48 were assessed by response subgroups.

Results:

266 pts receiving tofacitinib + MTX and 264 pts receiving tofacitinib + PBO in W24–48 were included. At W48: mean ACR-N was numerically greater with tofacitinib + MTX vs tofacitinib + PBO (60.8 vs 53.1); mean decrease in HAQ-DI was generally similar between groups (-0.71 vs -0.67); mean decrease in DAS28-4(ESR) was numerically greater with tofacitinib + MTX vs tofacitinib + PBO (-2.95 vs -2.68). The differences/similarities between groups in ACR-N and ΔHAQ-DI were also seen in cumulative probability plots (Figure 1). CRFP rates were numerically lower with tofacitinib + MTX (18.7%) vs tofacitinib + PBO (23.5%), and in pts with remission/LDA (tofacitinib + MTX, 12.1%; tofacitinib + PBO, 16.8%) vs moderate/high disease activity (tofacitinib + MTX, 26.2%; tofacitinib + PBO, 30.8%). Median of mean CRP over time was generally numerically lower in pts with CRFP vs non-CRFP and DAS28-4(ESR)-defined remission/LDA vs moderate/high disease activity; and in those receiving tofacitinib + PBO vs tofacitinib + MTX, irrespective of CRFP or DAS28-4(ESR) disease status (Table 1).

Table 1.

Median of mean CRPa up to W48 by response subgroups

Tofacitinib 11 mg QD + MTXTofacitinib 11 mg QD + PBOMean CRP,amedian (IQR) [n]>BL–W24>W24–48>BL–W24>W24–48HAQ-DI CRFP2.84 (1.15–7.30)2.30 (0.82–4.75)1.45 (0.77–4.42)2.28 (0.53–7.28)[45][46][56][56]HAQ-DI non-CRFP2.81 (1.09–6.19)2.91 (1.19–5.84)2.26 (0.98–4.63)2.47 (1.13–5.53)[195][195][176][178]DAS28-4(ESR) remission/LDA2.48 (1.05–4.95)2.46 (1.07–4.76)1.70 (0.89–4.14)1.95 (0.81–3.82)[126][127][115][117]DAS28-4(ESR) moderate/high disease activity3.56 (1.17–7.13)3.58 (1.36–8.33)2.60 (0.87–5.16)2.68 (1.34–8.23)[107][107][115][115]

aMean CRP was calculated as the average CRP value during each time period (>BL–W24 or >W24–48)

CRP, C-reactive protein; DAS28-4(ESR), Disease Activity Score in 28 joints, erythrocyte sedimentation rate; HAQ-DI, Health Assessment Questionnaire-Disability Index; IQR, interquartile range; LDA, low disease activity; MTX, methotrexate; n, number of pts meeting assessment criteria; QD, once daily

Conclusion:

Although clinical/functional responses were generally similar between treatment groups, numerical improvements were seen for some efficacy endpoints with tofacitinib + MTX vs tofacitinib + PBO. A numerically higher CRFP rate may be associated with higher DAS28-4(ESR) disease activity. CRP changes up to W48 may not trend with CRFP status.

References:

[1]Cohen et al. Lancet Rheumatol 2019; 1: E23-34.

Acknowledgements:

Study sponsored by Pfizer Inc. Medical writing support was provided by Anthony G McCluskey, CMC Connect, and funded by Pfizer Inc.

Disclosure of Interests:

Stanley B. Cohen Consultant of: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Grant/research support from: AbbVie, Eli Lilly, Genentech, Gilead Sciences, Pfizer Inc, Yi-Hsing Chen Grant/research support from: Bristol-Myers Squibb, GlaxoSmithKline, Pfizer Inc, Naonobu Sugiyama Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Jose Luis Rivas Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Annette Diehl Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Tatjana Lukic Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Jerome Paulissen Consultant of: Pfizer Inc, Haiyun Fan Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Tomohiro Hirose Shareholder of: Pfizer Inc, Employee of: Pfizer Inc, Edward Keystone Speakers bureau: AbbVie, Amgen, F. Hoffman-La Roche, Janssen, Merck, Novartis, Pfizer Inc, Sanofi Genzyme, Consultant of: AbbVie, Amgen, Bristol-Myers Squibb, Celltrion, Eli Lilly, F. Hoffman-La Roche, Gilead Sciences, Janssen, Merck, Myriad Autoimmune, Pfizer Inc, Sandoz, Sanofi Genzyme, Samsung Bioepsis, Grant/research support from: Amgen, Merck, Pfizer Inc, PuraPharm

LncRNA SNHG15 promotes the proliferation of nasopharyngeal carcinoma via sponging miR-141-3p to upregulate KLF9

OBJECTIVE

Long non-coding RNAs (lncRNAs) have been identified to exert an oncogenic or anti-tumor function in malignant tumors. LncRNA SNHG15 is verified to be an oncogene in hepatocellular carcinoma, colorectal cancer, and prostate cancer. In this paper, we mainly investigate the potential influence of SNHG15 on the progression of nasopharyngeal carcinoma (NPC).

PATIENTS AND METHODS

SNHG15 levels in NPC tissues and cell lines were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Correlation between SNHG15 level and prognosis of NPC patients was evaluated by the Kaplan-Meier method. Regulatory effects of SNHG15 on proliferative, colony formation abilities, and apoptosis of SUNE1 and CNE1 cells were assessed through a series of functional experiments. Potential miRNAs binding SNHG15 and the downstream gene of the microRNA (miRNA) were predicted by bioinformatics method, which was confirmed by Dual-Luciferase reporter gene assay and Western blot.

RESULTS

SNHG15 was upregulated in NPC tissues and cells. High level of SNHG15 indicated worse survival in NPC patients. Knockdown of SNHG15 markedly suppressed proliferative ability and induced apoptosis in SUNE1 and CNE1 cells. It is verified that miR-141-3p was the direct target binding SNHG15, and KLF9 was the downstream gene of miR-141-3p. SNHG15 was demonstrated to be a ceRNA to upregulate KLF9 by competitively binding miR-141-3p.

CONCLUSIONS

SNHG15 is upregulated in NPC tissues, and this aggravates the progression of NPC by absorbing miR-141-3p to upregulate KLF9.

Low-Temperature Aldol Condensation of Aldehydes on R-TiO2(100)-(1 × 1): Exceptional Selectivity for α,β-Unsaturated Enal Production

Selective C-C coupling of oxygenates via aldol condensation has the potential to produce useful chemicals from aldehydes and ketones. Here we report a combined experimental and theoretical study on the aldol condensation of unbranched aldehydes (C_nH_2n+1-CHO, n = 1-4) on rutile (R)-TiO₂(100)-(1 × 1). Experimental results show that the R-TiO₂(100)-(1 × 1) surface has a very high reactivity and selectivity for aldol product formation from tested aldehydes at room temperature. Theoretical calculations indicate that the CH₃CHO enolization and the aldol dehydration occur with low energy barriers, and the 3-butanolal intermediate adsorbs on R-TiO₂(100)-(1 × 1) stably, suggesting that the surface has a "modest" acid-base strength for efficient crotonaldehyde formation. The adsorption configuration of CH₃CHO and surface structure of R-TiO₂(100)-(1 × 1) may contribute to the exclusive selectivity of (E)-crotonaldehyde formation, which provides us a deep insight into the high selectivity of aldol condensation of aldehydes on the TiO₂ catalyst.

Quantitative characterisation of the ring normal modes. Pyridine as a study case

In the present work, the vibrational normal modes (NM) of pyridine were revisited. Quantum Chemical calculations were performed to help understand the true nature of some ring related vibrational normal modes (RNM) and how they may be correlated with the electronic structure on the ring. The 27 vibrational normal modes were decomposed into the molecular internal coordinates, and the interest was focused on 7 of them, involving the in-plane ring motion. The electronic structure was analysed through frontier Molecular Orbitals (MO), maps of Molecular Electrostatic Potential surfaces (MEPs) and Natural Bond Orbital (NBO) analysis in a dynamic manner, wherein, each vibration was scanned. The present investigation is aimed to provide the Reader with a quantitative characterisation of the RNMs of pyridine.

Spectroscopic Identification of Transition-Metal M[η2-(O,O)C] Species for Highly-Efficient CO2 Activation

The CO₂ activation by transition metals is important in CO₂ utilization but has proven to be challenging for experimental targets. Here we report first synthesis and spectroscopic characterization of transition-metal M[η²-(O,O)C] species with bidentate double oxygen metal-CO₂ coordination in the [ZrO(CO₂)_n≥4]⁺ complexes. The Zr[η²-(O,O)C] species yields a CO₂^- radical ligand, showing a high efficiency in CO₂ activation. We find that two important prerequisites are demanded for certain metals to form this intriguing M[η²-(O,O)C] species. One is that the metal center has high reduction capability, and the other is that the oxidation state of the metal center is lower than its highest one by 1. This study highlights the pivotal roles played by the M[η²-(O,O)C] species in CO₂ activation and also open new avenues toward the development of related single-atom catalysts with isolated transition-metal atoms dispersed on supports.