*H migration-assisted MvK mechanism for efficient electrochemical NH3 synthesis over TM-TiNO.

The electrochemical NH3 synthesis on TiNO is proposed to follow the Mars-van Krevelen (MvK) mechanism, offering more favorable N2 adsorption and activation on the N vacancy (Nv) site, compared to the conventional associative mechanism. The regeneration cycle of Nv represents the rate-determining step in this process. This study investigates a series of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt)-TiNO to explore the *H migration (from TM to TiNO)-promoted Nv cycle. The screening results indicate that Ni-TiNO exhibits strong H2O decomposition for *H production with 0.242 eV and low *H migration resistance with 0.913 eV. Notably, *H migration from Ni to TiNO significantly reduces the Nv formation energy to 0.811 eV, compared to 1.387 eV on pure TiNO. Meanwhile, in the presence of *H, Nv formation takes precedence over Tiv and Ov. Lastly, electronic performance calculations reveal that the collaborative function provided by Ni and Nv enables highly stable and efficient NH3 synthesis. The *H migration-assisted MvK mechanism demonstrates effective catalytic cycle performance in electrochemical N2 fixation and may have potential applicability to other hydrogenation reactions utilizing water as a proton source.

Alter codon bias of the P. pastoris genome to overcome a bottleneck in codon optimization strategy development and improve protein expression.

Apart from its role in translation, codon bias is also an important mechanism to regulate mRNA levels. The traditional frequency-based codon optimization strategy is rather efficient in organisms such as N. crassa, but much less in yeast P. pastoris which is a popular host for heterologous protein expression. This is because that unlike N. crassa, the preferred codons of P. pastoris are actually AU-rich and hence codon optimization for extremely low GC content comes with issues of pre-mature transcriptional termination or low RNA stability in spite of translational advantages. To overcome this bottleneck, we focused on three reporter genes in P. pastoris first and confirmed the great advantage of GC-prone codon optimization on mRNA levels. Then we altered the codon bias profile of P. pastoris by introducing additional rare tRNA gene copies. Prior to that we constructed IPTG-regulated tRNA species to enable chassis cells to switch between different codon bias status. As demonstrated again with reporter genes, protein yield of luc and 0788 was successfully increased by 4-5 folds in chassis cells. In summary, here we provide an alternative codon optimization strategy for genes with unsatisfactory performance under traditional codon frequency-based optimization.

Fe-Bi dual sites regulation of Bi2O2.33 nanosheets to promote photocatalytic nitrogen fixation activity.

In the process of photocatalytic ammonia synthesis, efficient activation of nitrogen molecules constitutes a fundamental challenge. During the N2 activation, the close interdependence between the acceptance and donation of electron results in their mutual limitation, leading to high energy barrier for N2 activation and unsatisfactory photocatalytic performance. This work decoupled the electron acceptance and donation processes by constructing Fe-Bi dual active sites, resulting in enhancing N2 activation through the high electron trapping ability of Fe3+ and strong electron donating ability of Bi2+. The photocatalytic nitrogen reduction efficiency of 3%Fe/Bi2O2.33 (118.71 µmol gcat-1h-1) is 5.3 times that of Bi2O2.33 (22.41 µmol gcat-1h-1). In-situ Fourier transform infrared (In situ FTIR) spectroscopy and density functional theory (DFT) calculations manifest that Fe3+-Bi2+ dual active sites work together to promote nitrogen adsorption and activation, and the reaction path is more inclined toward alternate hydrogenation path. N2 adsorption and activation properties are optimized by heteronuclear bimetallic active sites, which offers a new way for the rational design of nitrogen-fixing photocatalysts.

Enhanced photocatalytic hydrogen evolution of Ru/TiO2-x via oxygen vacancy-assisted hydrogen spillover process.

Hydrogen spillover effects will significantly improve the activity of photocatalytic hydrogen evolution reactions (HER), while their introduction and optimization require the construction of an excellent metal/support structure. In this study, we have synthesized Ru/TiO2-x catalysts with controlled oxygen vacancy (OVs) concentrations using a simple one-pot solvothermal method. The results show that Ru/TiO2-x3 with the optimal OVs concentration exhibits an unprecedentedly high H2 evolution rate of 13604 µmol·g-1·h-1, which was 45.7 and 2.2 times higher than that of TiO2-x (298 µmol·g-1·h-1) and Ru/TiO2 (6081 µmol·g-1·h-1). Controlled experiments, detailed characterizations, and theoretical calculations have revealed that the introduction of OVs on the carrier contributes to the hydrogen spillover effect in the metal/support system photocatalyst and that the process of hydrogen spillover in this system can be optimized by modulating the OVs concentration. This study proposes a strategy to decrease the energy barrier of hydrogen spillover and enhance photocatalytic HER activity. Moreover, it investigates the effect of OVs concentration on the hydrogen spillover effect in the photocatalytic metal/supports system.

Geographical, climatic, and soil factors control the altitudinal pattern of rhizosphere microbial diversity and its driving effect on root zone soil multifunctionality in mountain ecosystems.

Shifts in rhizosphere soil microorganisms of dominant plants' response to climate change profoundly impact mountain soil ecosystem multifunctionality; relatively little is known about the relationship between them and how they depend on long-term environmental drivers. Here, we conducted analyses of rhizosphere microbial altitudinal pattern, community assembly, and co-occurrence network of 6 dominant plants in six typical vegetation zones ranging from 1350 to 2900 m (a.s.l.) in Helan Mountains by absolute quantitative sequencing technology, and finally related the microbiomes to root zone soil multifunctionality ('soil multifunctionality' hereafter), the environmental dependence of the relationship was explored. It was found that the altitudinal pattern of rhizosphere soil bacterial and fungal diversities differed significantly. Higher co-occurrence and more potential interactions of Stipa breviflora and Carex coninux were found at the lowest and highest altitudes. Bacterial α diversity, the identity of some dominant bacterial and fungal taxa, had significant positive or negative effects on soil multifunctionality. The effect sizes of positive effects of microbial diversity on soil multifunctionality were greater than those of negative effects. These results indicated that the balance of positive and negative effects of microbes determines the impact of microbial diversity on soil multifunctionality. As the number of microbes at the phylum level increases, there will be a net gain in soil multifunctionality. Our study reveals that geographical and climatic factors can directly or modulate the effects of soil properties on rhizosphere microbial diversity, thereby affecting the driving effect of microbial diversity on soil multifunctionality, and points to the rhizosphere bacterial diversity rather than the fungi being strongly associated with soil multifunctionality. This work has important ecological implications for predicting how multiple environment-plant-soil-microorganisms interactions in mountain ecosystems will respond to future climate change.

Geographic Distribution of HCV Genotypes and Efficacy of Direct-Acting Antivirals in Chronic HCV-Infected Patients in North and Northeast China: A Real-World Multicenter Study.

Objective: To assess the geographic distribution of HCV genotypes, effectiveness, and safety of DAA treatment for HCV-infected patients in North and Northeast China. Methods: The geographic distribution of HCV genotypes was analyzed in 2162 patients recruited from April 2018 to February 2021. Sustained virologic response rates at 12 (SVR12) or 24 (SVR24) weeks posttreatment and safety were analyzed in 405 patients who completed DAA treatment according to patient baseline characteristics and treatment. Results: Four genotypes and six subtypes were identified as follows: 1b (1187, 54.90%), 2a (790, 36.54%), 3a/b (134, 6.20%), 6a/n (44, 2.04%), mixed genotypes (2a-6a or 2a-3a) (7, 0.32%). Overall, 99.01% patients achieved SVR12, while 98.43% achieved SVR24. All patients treated with elbasvir/grazoprevir (EBR/GZR), sofosbuvir/velpatasvir ± ribavirin (SOF/VEL ± RBV), and SOF/ledipasvir (LDV) achieved SVR12 or SVR24; 92.86% SVR12 and 95.83% SVR24 were observed in patients using SOF + RBV. SVR12 was higher in noncirrhosis versus compensated cirrhosis patients (100% vs. 97.09%, p=0.022). No severe drug-related adverse event was observed. Conclusions: Genotypes 1b and 2a were dominant subtypes in North and Northeast China. The approved drug regimens EBR/GZR and SOF/LDV for subtype 1b and SOF/VEL for nongenotype 1b are the optimal effective and safety profile.

Identification and Validation of Novel Biomarkers for Hepatocellular Carcinoma, Liver Fibrosis/Cirrhosis and Chronic Hepatitis B via Transcriptome Sequencing Technology.

Purpose: The aim of this study was to identify and validate novel biomarkers for distinguishing among hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), liver fibrosis/liver cirrhosis (LF/LC) and chronic hepatitis B (CHB). Patients and Methods: Transcriptomic sequencing was conducted on the liver tissues of 5 patients with HCC, 5 patients with LF/LC, 5 patients with CHB, and 4 healthy controls. The expression levels of selected mRNAs and proteins were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical (IHC) staining, and were verified in validation set (n=200) and testing set (n=400) via enzyme-linked immunosorbent assay (ELISA). Results: A total of 9 hub mRNAs were identified by short time-series expression miner and weighted gene co-expression network analysis. Of note, the results of qRT-PCR and IHC staining demonstrated that SHC adaptor protein 1 (SHC1), SLAM family member 8 (SLAMF8), and interleukin-32 (IL-32) exhibited gradually increasing trends in the four groups. Subsequent ELISA tests on the validation cohort indicated that the plasma levels of SHC1, SLAMF8 and IL-32 also gradually increased. Furthermore, a diagnostic model APFSSI (age, PLT, ferritin, SHC1, SLAMF8 and IL-32) was established to distinguish among CHB, LF/LC and HCC. The performance of APFSSI model for discriminating CHB from healthy subjects (AUC=0.966) was much greater compared to SHC1 (AUC=0.900), SLAMF8 (AUC=0.744) and IL-32 (AUC=0.821). When distinguishing LF/LC from CHB, APFSSI was the most outstanding diagnostic parameter (AUC=0.924), which was superior to SHC1, SLAMF8 and IL-32 (AUC=0.812, 0.684 and 0.741, respectively). Likewise, APFSSI model with the greatest AUC value displayed an excellent performance for differentiating between HCC and LF/LC than other variables (SHC1, SLAMF8 and IL-32) via ROC analysis. Finally, the results in the test set were consistent with those in the validation set. Conclusion: SHC1, SLAMF8 and IL-32 can differentiate among patients with HCC, LF/LC, CHB and healthy controls. More importantly, the APFSSI model greatly improves the diagnostic accuracy of HBV-associated liver diseases.

Plasma Golgi protein 73 levels predict prognosis of HCV-related hepatic fibrosis.

OBJECTIVES: To explore the correlation between plasma Golgi protein 73 (GP73) and progression of hepatitis C virus (HCV)-induced hepatic fibrosis. METHODS: A total of 232 subjects of chronic hepatitis C and 31 healthy controls were enrolled from the Third Hospital of Hebei Medical University from January 2010 to September 2018. The plasma GP73 levels were detected by ELISA. Liver tissue sections stained with hematoxylin and eosin and Masson-trichrome were examined under a light microscope based on the METAVIR scoring system and "Beijing classification (P-I-R)". The correlation analysis and receiver operating characteristic (ROC) curve were performed to analyze the diagnostic efficiency of plasma GP73, APRI, and FIB-4 for staging hepatic fibrosis and predicting the disease progression. RESULTS: The plasma GP73 levels were increased with the progression of liver fibrosis, and GP73 concentrations in healthy controls, HCV patients with fibrosis stage 1, 2, 3 and 4 were 94.82, 151.3, 157.9, 181.7 and 208.5 ng/ml, respectively. According to "Beijing classification", There was a statistically significant difference in plasma GP73 concentrations between patients in the progression and regressive / indeterminate group (177.08 vs 154.00 ng/ml , P = 0.007).The area under the ROC curves (AUCs) of GP73, APRI, and FIB-4 for diagnosis of liver cirrhosis were 0.89, 0.77, and 0.82, respectively, and GP73 for progressive fibrosis was 0.73. The plasma GP73 levels were significantly positively correlated with hepatic inflammation, serum ALT, and negatively correlated with albumin levels. CONCLUSION: The plasma GP73 might be a potential biomarker for staging liver fibrosis, and could predict regression or progression of HCV-related liver fibrosis.

Heme oxygenase-1 alleviated non-alcoholic fatty liver disease via suppressing ROS-dependent endoplasmic reticulum stress.

AIMS: The endoplasmic reticulum (ER) stress response plays a crucial role in the development of nonalcoholic steatohepatitis (NASH). Heme oxygenase-1 (HO-1) exerts beneficial effects against oxidative injury in NASH. This study is aimed to clarify whether HO-1 is an effective therapeutic strategy for NASH via regulation of ER stress. METHODS: The C57BL/6J mice were fed with methionine-choline deficient (MCD) for 4 weeks and high fat-high carbohydrate-high cholesterol (HFD) diet for 16 weeks, with hemin or zinc protoporphyrin IX (ZnPP-IX), respectively. The LO-2 cells were cultured in palmitic medium, with transfected pEX-HO-1 or sh-HO-1 plasmid for 24 h. Meanwhile, thirty NASH patients and 15 health controls were enrolled. The ER ultrastructure was observed by transmission electron microscopy (TEM) and confocal microscopy. The expressions of mRNAs and proteins of HO-1, ER stress related genes were detected by real time PCR, western blot and immunohistochemical staining, respectively. RESULTS: The swelled and broken rough endoplasmic reticulums were observed in MCD and HFD fed mice. The reactive hepatic expression of HO-1 was related with the increased ROS production and ER stress, companied with upregulation of GRP78, p-IRE1, PERK, ATF6. Through hemin administration, hepatocyte apoptosis was suppressed companied down-regulation of CHOP, caspase12 and up-regulation of BCL2. Conserved results were exhibited in ZnPP-IX administrated mice and HO-1 silent cells. Consistent results were observed in the NASH Patients. CONCLUSIONS: HO-1 could serve as a protective factor in the progression of nutritional steatohepatitis by suppresses hepatocyte excessive ER stress and might be a potential target for therapy of nonalcoholic steatohepatitis.