Spectrum-effect relationship between HPLC fingerprint and hypoglycemic of litchi leaves (Litchi chinensis Sonn) in vitro.

Litchi chinensis Sonn (Litchi) has been listed in the Chinese Pharmacopeia, and is an economically and medicinally valuable species within the family Sapindaceae. However, the material basis of its pharmacological action and the pharmacodynamic substances associated with its hypoglycemic effect are still unclear. The predominant objective of this study was to establish the fingerprint profile of litchi leaves and to evaluate the relationship between the components of the high-performance liquid chromatography (HPLC) fingerprint of litchi leaves, assess its hypoglycemic effect by measuring α-glucosidase and α-amylase inhibition, and find the spectrum-effect relationship of litchi leaves by bivariate correlation analysis, Grey relational analysis and partial least squares regression analysis. In this study, the fingerprint of litchi leaves was established by HPLC, and a total of 15 common peaks were identified that clearly calibrated eight components, with P1 being gallic acid, P2 being protocatechuic acid, P3 being catechin, P6 being epicatechin, P12 being rutin, P13 being astragalin, P14 being quercetin and P15 being kaempferol. The similarities between the fingerprints of 11 batches of litchi leaves were 0.766-0.979. Simultaneously, the results of the spectrum-effect relationship showed that the chemical constituents represented by peaks P8, P3, P12, P14, P2, P13, and P11 were relevant to the hypoglycemic effect.

[Identification of HSP70 gene family members in Fritillaria cirrhosa and expression analysis in different tissues under high temperature stress].

The heat shock protein 70 family contains the stress proteins ubiquitous in plants. These proteins are involved in the responses to different abiotic stress conditions and have highly conserved gene sequences. However, little is known about the molecular mechanisms of Fritillaria cirrhosa in response to high-temperature stress. Here, 26 HSP70s, FcHSP70-1 to FcHSP70-26, were identified from the transcriptome data of root, bulb, stem, leaf, and fruit samples of F. cirrhosa. The proteins encoded by FcHSP70s had the lengths ranging from 560 aa to 944 aa, with the molecular weight of 61.64-100.01 kDa and the theoretical isoelectric point between 5.00 and 6.59. The secondary structural elements of HSP70s were mainly random coils and α-helixes. Subcellular localization prediction revealed that FcHSP70s were distributed in mitochondria, chloroplasts, nuclei, endoplasmic reticulum, and cytoplasm. The phylogenetic tree showed that 7 members of the HSP70 family belonged to the Dnak subfamily and 19 members belonged to the HSP110/SSE subfamily. In addition, the qRT-PCR results showed that the expression of FcHSP70-5, FcHSP70-8, FcHSP70-17, FcHSP70-18, and FcHSP70-23 in F. cirrhosa was significantly up-regulated at 35 ℃, which indicated that these genes might play a role in the response to high temperature stress. In addition, compared with other tissues, stems and leaves were sensitive to high temperature stress, with the expression of 18 genes up-regulated by 18.18 and 8.03 folds on average, respectively. These findings provide valuable information about the molecular mechanism of HSP70s of F. cirrhosa in response to high temperature stress.

Genome-wide identification and expression analysis of the C2H2-zinc finger transcription factor gene family and screening of candidate genes involved in floral development in Coptis teeta Wall. (Ranunculaceae).

Background: C2H2-zinc finger transcription factors comprise one of the largest and most diverse gene superfamilies and are involved in the transcriptional regulation of flowering. Although a large number of C2H2 zinc-finger proteins (C2H2-ZFPs) have been well characterized in a number of model plant species, little is known about their expression and function in Coptis teeta. C. teeta displays two floral phenotypes (herkogamy phenotypes). It has been proposed that the C2H2-zinc finger transcription factor family may play a crucial role in the formation of floral development and herkogamy observed in C. teeta. As such, we performed a genome-wide analysis of the C2H2-ZFP gene family in C. teeta. Results: The complexity and diversity of C. teeta C2H2 zinc finger proteins were established by evaluation of their physicochemical properties, phylogenetic relationships, exon-intron structure, and conserved motifs. Chromosome localization showed that 95 members of the C2H2 zinc-finger genes were unevenly distributed across the nine chromosomes of C. teeta, and that these genes were replicated in tandem and segmentally and had undergone purifying selection. Analysis of cis-acting regulatory elements revealed a possible involvement of C2H2 zinc-finger proteins in the regulation of phytohormones. Transcriptome data was then used to compare the expression levels of these genes during the growth and development of the two floral phenotypes (F-type and M-type). These data demonstrate that in groups A and B, the expression levels of 23 genes were higher in F-type flowers, while 15 genes showed higher expressions in M-type flowers. qRT-PCR analysis further revealed that the relative expression was highly consistent with the transcriptome data. Conclusion: These data provide a solid basis for further in-depth studies of the C2H2 zinc finger transcription factor gene family in this species and provide preliminary information on which to base further research into the role of the C2H2 ZFPs gene family in floral development in C. teeta.

Multilayered regulation of secondary metabolism in medicinal plants.

Medicinal plants represent a huge reservoir of secondary metabolites (SMs), substances with significant pharmaceutical and industrial potential. However, obtaining secondary metabolites remains a challenge due to their low-yield accumulation in medicinal plants; moreover, these secondary metabolites are produced through tightly coordinated pathways involving many spatiotemporally and environmentally regulated steps. The first regulatory layer involves a complex network of transcription factors; a second, more recently discovered layer of complexity in the regulation of SMs is epigenetic modification, such as DNA methylation, histone modification and small RNA-based mechanisms, which can jointly or separately influence secondary metabolites by regulating gene expression. Here, we summarize the findings in the fields of genetic and epigenetic regulation with a special emphasis on SMs in medicinal plants, providing a new perspective on the multiple layers of regulation of gene expression.

EbbHLH80 Enhances Salt Responses by Up-Regulating Flavonoid Accumulation and Modulating ROS Levels.

bHLH transcription factors are involved in multiple aspects of plant biology, such as the response to abiotic stress. Erigeron breviscapus is a composite plant, and its rich flavonoids have strong preventive and therapeutic effects on cardio cerebral vascular disease. EbbHLH80, a gene from E. breviscapus that positively regulates flavonoid synthesis, was previously characterized. However, it is unclear whether EbbHLH80 increases flavonoid accumulation, which affects salt tolerance. The function of EbbHLH80 in transgenic tobacco seeds was identified by phylogenetic analysis and metabolome-transcriptome analysis. We investigated the role of EbbHLH80 in salt stress response. Our results showed that the expression of EbbHLH80 increased following salt treatment. Integrating the metabolome and transcriptome analysis of EbbHLH80-OE and Yunyan 87 (WT) seeds, we identified several genes and metabolites related to flavonoid biosynthesis and salt stress. Moreover, EbbHLH80-OE plants displayed higher salt tolerance than wild-type plants during seed germination and seedling growth. After salt treatment, transgenic tobacco had significantly lower levels of reactive oxygen species (ROS) than WT, with enhanced levels of antioxidant enzyme expression. Altogether, our results demonstrated that EbbHLH80 might be a positive regulator, promoting salt tolerance by modulating ROS scavenging and increasing stress-responsive genes.

Site-directed mutagenesis identified the key active site residues of 2,3-oxidosqualene cyclase HcOSC6 responsible for cucurbitacins biosynthesis in Hemsleya chinensis.

Hemsleya chinensis is a Chinese traditional medicinal plant, containing cucurbitacin IIa (CuIIa) and cucurbitacin IIb (CuIIb), both of which have a wide range of pharmacological effects, including antiallergic, anti-inflammatory, and anticancer properties. However, few studies have been explored on the key enzymes that are involved in cucurbitacins biosynthesis in H. chinensis. Oxidosqualene cyclase (OSC) is a vital enzyme for cyclizing 2,3-oxidosqualene and its analogues. Here, a gene encoding the oxidosqualene cyclase of H. chinensis (HcOSC6), catalyzing to produce cucurbitadienol, was used as a template of mutagenesis. With the assistance of AlphaFold2 and molecular docking, we have proposed for the first time to our knowledge the 3D structure of HcOSC6 and its binding features to 2,3-oxidosqualene. Mutagenesis experiments on HcOSC6 generated seventeen different single-point mutants, showing that single-residue changes could affect its activity. Three key amino acid residues of HcOSC6, E246, M261 and D490, were identified as a prominent role in controlling cyclization ability. Our findings not only comprehensively characterize three key residues that are potentially useful for producing cucurbitacins, but also provide insights into the significant role they could play in metabolic engineering.

RNA-seq analysis reveals key genes associated with seed germination of Fritillaria taipaiensis P.Y.Li by cold stratification.

Seed dormancy is an adaptive strategy for environmental evolution. However, the molecular mechanism of the breaking of seed dormancy at cold temperatures is still unclear, and the genetic regulation of germination initiated by exposure to cold temperature requires further investigation. In the initial phase of the current study, the seed coat characteristics and embryo development of Fritillaria taipaiensis P.Y.Li at different temperatures (0°C, 4°C, 10°C & 25°C) was recorded. The results obtained demonstrated that embryo elongation and the dormancy-breaking was most significantly affected at 4°C. Subsequently, transcriptome analyses of seeds in different states of dormancy, at two stratification temperatures (4°C and 25°C) was performed, combined with weighted gene coexpression network analysis (WGCNA) and metabolomics, to explore the transcriptional regulation of seed germination in F. taipaiensis at the two selected stratification temperatures. The results showed that stratification at the colder temperature (4°C) induced an up-regulation of gene expression involved in gibberellic acid (GA) and auxin biosynthesis and the down-regulation of genes related to the abscisic acid (ABA) biosynthetic pathway. Thereby promoting embryo development and the stimulation of seed germination. Collectively, these data constitute a significant advance in our understanding of the role of cold temperatures in the regulation of seed germination in F. taipaiensis and also provide valuable transcriptomic data for seed dormancy for other non-model plant species.

Constructing a Pt/YMn2O5 Interface to Form Multiple Active Centers to Improve the Hydrothermal Stability of NO Oxidation.

The hydrothermal stability of NO oxidation is the key to the practical application of diesel oxidation catalysts in diesel engines, which in the laboratory requires that NO activity does not decrease after aging for 10 h with 10% H2O/air at 800 °C. On the one hand, the construction of a metal/oxide interface can lead to abundant oxygen vacancies (Ov), which compensate for the loss of activity caused by the aggregation of Pt particles after aging. On the other hand, YMn2O5 (YMO) has excellent thermal stability and NO oxidation capacity. Therefore, a Pt/YMn2O5-La-Al2O3 (Pt/YMO-LA) catalyst was prepared by the impregnation method. The support of the catalyst, YMn2O5-La-Al2O3 (YMO-LA), was obtained by mixing high specific surface LA and YMO ball-milling. Under laboratory-simulated diesel exhaust flow, the NO oxidation performance of Pt/YMO-LA did not decrease after hydrothermal aging. Combining high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and oxygen temperature-programmed desorption (O2-TPD), the Pt/YMn2O5 interface was formed after hydrothermal aging, and the increased Ov can provide reactive oxygen to Pt and YMO. The cooperative catalysis of multiple active centers composed of Pt, YMO, and Ov is the crucial factor to maintain the NO oxidation performance. In addition, in situ diffuse reflectance infrared Fourier transform spectra (DRIFTs) show that an increase in Ov is beneficial to the adsorption and desorption of more nitrate and nitrite intermediates, thus achieving the hydrothermal stability of NO oxidation.

Highly Efficient Dehydrogenation of Formic Acid over Binary Palladium-Phosphorous Alloy Nanoclusters on N-Doped Carbon.

Highly efficient dehydrogenation of formic acid (FA) at room temperature is a safe and suitable way to obtain hydrogen and promote the development of hydrogen storage application. Herein, the phosphorous-alloyed Pd nanoclusters loading on nitrogen-doped carbon (PdP/NC) were prepared and recognized as the highly active nanocatalysts for the dehydrogenation of FA. The PdP/NCs with controlled sizes and compositions were prepared by an easy self-limiting synthesis in an aqueous solution. The best PdP/NC exhibited a remarkable catalytic activity with a high turnover frequency of ∼3253.0 h-1 than the compared nanocatalysts for the dehydrogenation of FA at room temperature. The catalytic kinetics and durability studies showed that both the alloyed P in Pd crystals and doped N in the carbon support could effectively tailor the electronic states of the Pd surface and further optimize the adsorption energy of FA. Based on the Sabatier principle, the proper adsorption energy accelerated the dehydrogenation reaction and correspondingly enhanced the activity and durability. The work proposed a high-efficiency nanocatalyst for safe hydrogen generation and may be extended to create other similar nanocatalysts with different compositions and nanostructures.

Catalytic performance promoted on Pt-based diesel oxidation catalyst assisted by polyvinyl alcohol.

Eliminating vehicle emission is of importance due to the severe limit value. The work reports a convenient strategy of improving dispersion of platinum-based catalyst with the assistance of polyvinyl alcohol in a varied addition amount. Following the "two-step" annealing techniques, the catalytic performance of the polymer-assisted catalysts in diesel was obviously enhanced because of the improved dispersion of the platinum. Based on experimental results, the long chains of polymer resulting in the steric effect are presumed to isolate platinum ion, inhibiting the aggregation of platinum particles and then improving its dispersion. And the hydroxyl bonding between the polymers could convey electron to platinum species, leading to the lower platinum valence state. Both effects are positive resulting in an excellent NO maximum conversion of around 65% at the optimal introduction of 5 mass% of polymer, as the diesel oxidation catalyst (DOC), which could be inclined to a good purification in the diesel aftertreatment. Hopefully, the convenient research method could initiate the exploration and application of polymer-assisted catalysts for well-dispersed noble metal nanoparticles in eliminating exhaust emission.

Cerebral functional activity and connectivity changes in anti-N-methyl-D-aspartate receptor encephalitis: A resting-state fMRI study.

BACKGROUND: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis showing severe neuropsychiatric symptoms is the most common type of autoimmune encephalitis. However, the corresponding standard clinical magnetic resonance imaging (MRI) presents normal or atypical in the majority of patients with anti-NMDAR encephalitis. Here, this study aimed to investigate the alterations in brain functional activity in patients with anti-NMDAR encephalitis and whether these alterations contributed to cognition and mood disorders. METHODS: Seventeen patients with anti-NMDAR encephalitis and eighteen gender, age and education-matched healthy controls were recruited. All participants underwent neuropsychological tests (including Montreal Cognitive Assessment (MoCA), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD24)) and resting-state functional MRI. MRI data was firstly analyzed by amplitude of low-frequency fluctuation (ALFF), and brain regions with altered ALFF between groups were selected as regions of interest for the further functional connectivity (FC) analysis. Correlation analyses were performed to investigate the associations between brain dysfunction and neuropsychological performance. RESULTS: Relative to the healthy controls, patients with anti-NMDAR encephalitis performed inferiorly in the MoCA score, and showed anxiety and depression disorders with higher HAMA and HAMD24 scores (all p < 0.05). In the brain functional activity analysis, the patients showed decreased ALFF values in the bilateral posterior cingulate gyrus, left precuneus, and bilateral cerebellum (false- discovery- rate corrected, p < 0.05). Furthermore, relative to the control group, the patients showed significantly increased FC between the left posterior cingulate cortex (PCC) and the bilateral lingual gyrus, right calcarine, right cuneus, also between the right PCC and the right fusiform gyrus, bilateral lingual gyrus, left calcarine, left cuneus, and right posterior central gyrus (false- discovery- rate corrected, p < 0.05). FC strength between the left posterior cingulate gyrus and right cuneus, and between the right posterior cingulate gyrus and left cuneus were both positively correlated with MoCA memory scores (r = 0.485, p = 0.048; r = 0.550, p = 0.022). CONCLUSION: The present study highlight that decreased spontaneous neural activities and abnormal FC exhibited in the patients with anti-NMDAR encephalitis, which may participate in the process of cognition and emotion deficits. These results may help to elucidate the clinical radiological contradictions in anti-NMDAR encephalitis and contribute to deeper understanding of the pathophysiological mechanism of the disease.

EbARC1, an E3 Ubiquitin Ligase Gene in Erigeron breviscapus, Confers Self-Incompatibility in Transgenic Arabidopsis thaliana.

Erigeron breviscapus (Vant.) Hand.-Mazz. is a famous traditional Chinese medicine that has positive effects on the treatment of cardiovascular and cerebrovascular diseases. With the increase of market demand (RMB 500 million per year) and the sharp decrease of wild resources, it is an urgent task to cultivate high-quality and high-yield varieties of E. breviscapus. However, it is difficult to obtain homozygous lines in breeding due to the self-incompatibility (SI) of E. breviscapus. Here, we first proved that E. breviscapus has sporophyte SI (SSI) characteristics. Characterization of the ARC1 gene in E. breviscapus showed that EbARC1 is a constitutive expression gene located in the nucleus. Overexpression of EbARC1 in Arabidopsis thaliana L. (Col-0) could cause transformation of transgenic lines from self-compatibility (SC) into SI. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays indicated that EbARC1 and EbExo70A1 interact with each other in the nucleus, and the EbARC1-ubox domain and EbExo70A1-N are the key interaction regions, suggesting that EbARC1 may ubiquitinate EbExo70A to regulate SI response. This study of the SSI mechanism in E. breviscapus has laid the foundation for further understanding SSI in Asteraceae and breeding E. breviscapus varieties.

Voxel-based analysis and multivariate pattern analysis of diffusion tensor imaging study in anti-NMDA receptor encephalitis.

PURPOSE: This study aimed to investigate brain white matter (WM) changes and their relationship to cognition in patients with anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis. Multivariate pattern analysis (MVPA) was used to explore brain regions that play an important role in classification. METHODS: Fifteen patients and fifteen controls underwent Montreal Cognitive Assessment (MoCA) and diffusion tensor imaging. Based on fractional anisotropy (FA) and mean diffusivity (MD) for MVPA classification, the weights of each brain region were calculated. RESULTS: Compared with the controls, the patients showed an FA reduction in right middle temporal gyrus, left middle cerebellar peduncle, right praecuneus, and an MD increase in left medial temporal gyrus and left frontal lobe. The MoCA score for patients was lower than controls, especially in executive function, fluency, delayed recall and visual perception items. The FA value of right praecuneus was positively correlated with total MoCA score and fluency score. The MD of left frontal lobe was negatively correlated with total MoCA score, and MD of the left medial temporal gyrus was positively correlated with delayed recall. The accuracy, sensitivity and specificity of classification based on FA were 70%, 60% and 80%, respectively. Based on MD, they were each 80%. The brain regions with large weights from FA and MD overlap in temporal lobe, cerebellum and hippocampus. CONCLUSIONS: These results suggest that WM changes are associated with cognitive deficits. MVPA based on FA and MD has good classification ability. Our study may provide new insights into the pathophysiological mechanisms of residual cognitive deficits.

Radiomics approach for preoperative identification of stages I-II and III-IV of esophageal cancer.

OBJECTIVE: To predict preoperative staging using a radiomics approach based on computed tomography (CT) images of patients with esophageal squamous cell carcinoma (ESCC). METHODS: This retrospective study included 154 patients (primary cohort: n=114; validation cohort: n=40) with pathologically confirmed ESCC. All patients underwent a preoperative CT scan from the neck to abdomen. High throughput and quantitative radiomics features were extracted from the CT images for each patient. A radiomics signature was constructed using the least absolute shrinkage and selection operator (Lasso). Associations between radiomics signature, tumor volume and ESCC staging were explored. Diagnostic performance of radiomics approach and tumor volume for discriminating between stages I-II and III-IV was evaluated and compared using the receiver operating characteristics (ROC) curves and net reclassification improvement (NRI). RESULTS: A total of 9,790 radiomics features were extracted. Ten features were selected to build a radiomics signature after feature dimension reduction. The radiomics signature was significantly associated with ESCC staging (P<0.001), and yielded a better performance for discrimination of early and advanced stage ESCC compared to tumor volume in both the primary [area under the receiver operating characteristic curve (AUC): 0.795vs. 0.694, P=0.003; NRI=0.424)] and validation cohorts (AUC: 0.762 vs. 0.624, P=0.035; NRI=0.834). CONCLUSIONS: The quantitative approach has the potential to identify stage I-II and III-IV ESCC before treatment.

Validation of Breast Cancer Models for Predicting the Nonsentinel Lymph Node Metastasis After a Positive Sentinel Lymph Node Biopsy in a Chinese Population.

OBJECTIVES: Over the years, completion axillary lymph node dissection is recommended for the patients with breast cancer if sentinel lymph node metastasis is found. However, not all of these patients had nonsentinel lymph node metastasis on final histology. Some predicting models have been developed for calculating the risk of nonsentinel lymph node metastasis. The aim of our study was to validate some of the predicting models in a Chinese population. METHOD: Two hundred thirty-six patients with positive sentinel lymph node and complete axillary lymph node dissection were included. Patients were applied to 6 models for evaluation of the risk of nonsentinel lymph node involvement. The receiver-operating characteristic curves were shown in our study. The calculation of area under the curves and false negative rate was done for each model to assess the discriminative power of the models. RESULTS: There are 105 (44.5%) patients who had metastatic nonsentinel lymph node(s) in our population. Primary tumor size, the number of metastatic sentinel lymph node, and the proportion of metastatic sentinel lymph nodes/total sentinel lymph nodes were identified as the independent predictors of nonsentinel lymph node metastasis. The Seoul National University Hospital and Louisville scoring system outperformed the others, with area under the curves of 0.706 and 0.702, respectively. The area under the curve values were 0.677, 0.673, 0.432, and 0.674 for the Memorial Sloan-Kettering Cancer Center, Tenon, Stanford, and Shanghai Cancer Hospital models, respectively. With adjusted cutoff points, the Louisville scoring system outperformed the others by classifying 26.51% of patients with breast cancer to the low-risk group. CONCLUSION: The Louisville and Seoul National University Hospital scoring system were found to be more predictive among the 6 models when applied to the Chinese patients with breast cancer in our database. Models developed at other institutions should be used cautiously for decision-making regarding complete axillary lymph node dissection after a positive biopsy in sentinel lymph node.

Identification and Characterization of Genes Involved in Benzylisoquinoline Alkaloid Biosynthesis in Coptis Species.

The dried rhizomes of Coptis chinensis have been extensively used in heat clearing, dampness drying, fire draining, and detoxification by virtue of their major bioactive components, benzylisoquinoline alkaloids (BIAs). However, C. teeta and C. chinensis are occasionally interchanged, and current understanding of the molecular basis of BIA biosynthesis in these two species is limited. Here, berberine, coptisine, jatrorrhizine, and palmatine were detected in two species, and showed the highest contents in the roots, while epiberberine were found only in C. chinensis. Comprehensive transcriptome analysis of the roots and leaves of C. teeta and C. chinensis, respectively, identified 53 and 52 unigenes encoding enzymes potentially involved in BIA biosynthesis. By integrating probable biosynthetic pathways for BIAs, the jatrorrhizine biosynthesis ill-informed previously was further characterized. Two genes encoding norcoclaurine/norlaudanosoline 6-O-methyltransferases (Cc6OMT1 and Cc6OMT2) and one gene encoding norcoclaurine-7OMT (Ct7OMT) catalyzed enzymatically O-methylate (S)-norcoclaurine at C6 that yield (S)-coclaurine, along with a smaller amount of O-methylation occurred at C7, thereby forming its isomer (isococlaurine). In addition, scoulerine 9-OMT (CtSOMT) was determined to show strict substrate specificity, targeting (S)-scoulerine to yield (S)-tetrahydrocolumbamine. Taken together, the integration of the transcriptome and enzyme activity assays further provides new insight into molecular mechanisms underlying BIA biosynthesis in plants and identifies candidate genes for the study of synthetic biology in microorganisms.

Expression of PBMC apoptosis-related factors in patients with chronic hepatitis B and their relationships with clinical prognosis.

The present study was conducted to investigate the expression of apoptosis-related factors in peripheral blood mononuclear cells (PBMC) of patients with chronic hepatitis B and their correlation to clinical prognosis. Sixty-two patients that were diagnosed with chronic hepatitis B were admitted to Xuzhou Hospital from March 2015 to February 2016 and were enrolled as the observation group, while 60 healthy subjects who were examined in the health examination center were selected as the control group. The PBMC of patients were collected, and mRNA expression levels of the apoptotic molecules (FAS, CASP3, CASP8 and CASP9) were measured using real-time fluorescence quantitative PCR. The protein expression levels of apoptosis-related genes in the plasma were detected using enzyme-linked immunosorbent assay (ELISA) and the serum HBV-DNA was quantitatively measured using real-time fluorescence quantitative PCR. The mRNA and protein expression levels of FAS, CASP3, CASP8 and CASP9 in the observation group were significantly higher than those in the control group (P<0.05). The positive rate and log value of the copy amount of HBV DNA in the observation group were significantly higher than those in the control group (P<0.05). The Pearson correlation coefficient analysis showed that FAS, CASP3, CASP8 and CASP9 were positively correlated with HBV DNA (P<0.05). The mRNA expression levels of FAS, CASP3, CASP8 and CASP9 in patients with negative HBV-DNA were significantly lower than those with positive HBV-DNA (P<0.05). Apoptosis of PBMCs play an important role in the occurrence and development of chronic hepatitis B, and is closely correlated to the level of serum virus replication and prognosis.

Interactional effect of cerium and manganese on NO catalytic oxidation.

To preferably catalyze the oxidation of NO to NO2 in diesel after-treatment system, a series of CeO2-MnO x composite oxides was supported on silica-alumina material by the co-impregnation method. The maximum conversion of NO of the catalyst with a Ce/Mn weight ratio of 5:5 was improved by around 40%, compared to the supported manganese-only or cerium-only sample. And its maximum reaction rate was 0.056 µmol g-1 s-1 at 250 °C at the gas hourly space velocity of 30,000 h-1. The experimental results suggested that Ce-Mn solid solution was formed, which could modulate the valence state of cerium and manganese and exhibit great redox properties. Moreover, the strong interaction between ceria and manganese resulted in the largest desorption amount of strong chemical oxygen and oxygen vacancies, leading to the maximum O α area ratio of 62.26% from the O 1s result. These effective oxygen species could be continually transferred to the surface, leading to the best NO catalytic activity of 5Ce5Mn/SA catalyst. Graphical abstract.

Effect of the grafting ratio of poly(N-isopropylacrylamide) on thermally responsive polymer brush surfaces.

Four kinds of poly(N-isopropylacrylamide)-grafted silicas with different grafting ratios and the same grafting density were prepared by atom transfer radical polymerization. The chemical groups in the stationary phase was verified by FTIR spectroscopy, and the content of elements was measured by elemental analysis. The grafting ratio of thermoresponsive chromatographic materials was measured by thermogravimetric analysis and was 2.36-21.10% mg/m2 . The retention behaviors of the stationary phase with different grafting ratios were evaluated by separating five kinds of steroids and ten kinds of different hydrophobic properties compounds. With the increase in grafting ratio, the retention time of analytes was prolonged in high-performance liquid chromatography. The results showed that grafting ratio had a significant influence on the separation effect under the same grafting density. And the optimal grafting ratio of poly(N-isopropylacrylamide) was 5.81-13.15%.

CO oxidation catalyzed by the single Co atom embedded hexagonal boron nitride nanosheet: a DFT-D study.

A single metal atom stabilized on two dimensional materials (such as graphene and h-BN) exhibits extraordinary activity in the oxidation of CO. The oxidation of CO by molecular O2 on a single cobalt atom embedded in a hexagonal boron nitride monolayer (h-BN) is investigated using first-principles calculations with dispersion-correction. It is found that the single Co atom prefers to reside in a boron vacancy and possesses great stability. There are three mechanisms for CO oxidation: the traditional Eley-Rideal (ER) and Langmuir-Hinshelwood (LH) mechanisms and the termolecular Eley-Rideal (TER) mechanism proposed recently. Given the relatively small reaction barriers of the rate-limiting steps for the ER, LH and TER mechanisms (0.59, 0.55 and 0.41 eV, respectively), all three mechanisms are able to occur at low temperature. The current study may provide useful clues to develop low cost single atom catalysts.