Search

BackgroundBreast cancer is the most frequently diagnosed cancer and a leading cause of cancer-related death in women. Endoplasmic reticulum stress (ERS) plays a crucial role in the pathogenesis of several malignancies. However, the prognostic value of ERS-related genes in breast cancer has not been thoroughly investigated.MethodsWe downloaded and analyzed expression profiling data for breast invasive carcinoma samples in The Cancer Genome Atlas-Breast Invasive Carcinoma (TCGA-BRCA) and identified 23 ERS-related genes differentially expressed between the normal breast tissue and primary breast tumor tissues. We constructed and validated risk models using external test datasets. We assessed the differences in sensitivity to common antitumor drugs between high- and low-scoring groups using the Genomics of Drug Sensitivity in Cancer (GDSC) database, evaluated the sensitivity of patients in high- and low-scoring groups to immunotherapy using the Tumor Immune Dysfunction and Exclusion (TIDE) algorithm, and assessed immune and stromal cell infiltration in the tumor microenvironment (TME) using the Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression data (ESTIMATE) algorithm. We also analyzed the expression of independent factors in the prognostic model using the Western-blot analysis for correlation in relation to breast cancer.ResultsUsing multivariate Cox analysis, FBXO6, PMAIP1, ERP27, and CHAC1 were identified as independent prognostic factors in patients with breast cancer. The risk score in our model was defined as the endoplasmic reticulum score (ERScore). ERScore had high predictive power for overall survival in patients with breast cancer. The high-ERScore group exhibited a worse prognosis, lower drug sensitivity, and lower immunotherapy response and immune infiltration than did the low-ERScore group. Conclusions based on ERScore were consistent with Western-blot results.ConclusionWe constructed and validated for the first time an endoplasmic reticulum stress-related molecular prognostic model for breast cancer with reliable predictive properties and good sensitivity, as an important addition to the prognostic prediction model for breast cancer.

The nano-drug delivery system activated by the tumour microenvironment (TME) can effectively treat tumours with low toxicity. Based on a high level of reductive GSH in TME and the different coordination properties of Fe ions, this project intended to prepare a GSH-activated cascade catalytic nanoreactor for breast cancer treatment using Fe3+/Fe2+ as the molecular switch. In this study, the glucose oxidase (GOx) loaded iron alginate nano hydrogel (FeAlg/GOx) was prepared by the simple one-step titration method. Results showed that FeAlg/GOx could remain stable during in vivo circulation to avoid hypoglycaemia. When it reached the targeted tumour site, reductive GSH can reduce Fe3+ to Fe2+. Thereafter, FeAlg/GOx nanogel was broken and GOx was released to consume the essential nutrient glucose (Glu) to achieve tumour starvation therapy. Next, the substrate H2O2 generated by the reaction between GOx and Glu can be catalysed by Fe2+ to produce highly cytotoxic •OH in situ, which could further kill tumour cells. The in vivo pharmacodynamics results demonstrated that compared with the control group (V/V0 = 8.36 ± 1.73), FeAlg/GOx group showed the most significant anti-tumour effect with V/V0 of 3.08 ± 1.06. In conclusion, this "inactivated" FeAlg/GOx nanogel can be converted into "activated" therapeutic substances in situ to achieve starvation-chemodynamic combined treatment for breast cancer.

BackgroundHematopoietic stem cell transplantation (HSCT), as a mature technology, has significantly improved the survival rate of children. However, there lack efficient scales to assess the quality of life (QoL) of children with HSCT in China, which has important implications in the care of this population. This study aimed to translate the original English Pediatric Quality of Life Inventory™ (PedsQL™) Stem Cell Transplant Module into a Chinese mandarin version, and evaluate its reliability.MethodsChildren of ages 2–18 years who had received HSCT at Children's Hospital of Nanjing Medical University and Children's Hospital of Fudan University were recruited. Children or their parents were asked to fill the PedsQL™ 4.0 Generic Core Scales, PedsQL™ Stem Cell Transplant Module, and PedsQL™ Family Information Form. Feasibility was evaluated by completion rate and the percentage of missing items, reliability by the internal consistency and test-retest reliability, and validity by factor analysis and correlation analysis between the scores of total scale and each dimension.ResultsA total of 120 children (mean age 6.37, SD = 3.674) and some parents were included. A low percentage of items were missed in returned reports. Cronbach's alpha coefficient reached 0.70 in the majority of dimensions of both child self-report and parent proxy-report. Test-retest reliability was 0.685 in parents' forms and 0.765 in child's forms. Eight factors were extracted, with a cumulative contribution rate of 74.54%. The correlation between PedsQL™ 4.0 and Transplant Module was 0.748 for children self-report and 0.808 for parent proxy-report.ConclusionsThis study provides evidence that the Chinese mandarin version of the PedsQL™ Stem Cell Transplant is feasible, reliable and valid in evaluating the QoL of Chinese children after HSCT.

The Cooling-Storage-Ring External-target Experiment (CSR-CEE) is a spectrometer to study the nature of nuclear matter created in heavy ion collision at $\sqrt{s_{NN}} = $ 2.1 - 2.4 GeV, aiming to reveal Quantum Chromodynamics (QCD) phase structure in the high-baryon density region. Collective flow is regarded as an effective probe for studying the properties of the medium in high-energy nuclear collisions. One of the main functions of the Zero-Degree Calorimeter (ZDC), a sub-detector system in CEE, is to determine the reaction-plane in heavy ion collisions, which is crucial for the measurements of collective flow and other reaction plane related analysis. In this paper, we illustrate the procedures of event plane determination from ZDC. Finally, predictions of the rapidity dependence of directed and elliptic flow for $p$, $d$, $t$, $^3$He and $^4$He, from 2.1 GeV U+U collisions of IQMD model calculations, are presented., Comment: 7 pages, 9 figures

Additional file 1: Supplementary Figure S1. Localization of TP53 mutations at CpG and non-CpG sites in GC samples from Eastern Europe, China, and Japan (exon 4-8). Mutation-distribution maps were created using the cBioPortal mutation mapper ( http://www.cbioportal.org/mutation_mapper ). Black dots indicate truncating mutations (nonsense and frameshift mutations). The light purple dot indicates a silent mutation. P53_TAD, TP53 transcriptional activation domain; P53, TP53 DNA-binding domain; P53 tetramer, TP53 tetramer domain.

Supplementary Material 1

Additional file 5: Supplementary Figure S5. Mutation spectrum of the TP53 gene in GC in each population. Six substitution types are depicted in the bar graph as follows: C > A (light blue), C > G (black), C > T (red), T > A (gray), T > C (yellow-green), and T > G (pale orange).

Additional file 4: Supplementary Figure S4. Designations of populations based on TCGA classification. The majority of the data were from the “White” population. The “Asian” population was not defined, especially whether they were only residing in Asia or not. NA, not available.

Additional file 3: Supplementary Figure S3. Mutation spectra in intestinal and diffuse-type GCs in East Europe, China, and Japan. The TP53 mutations were classified into six types of single nucleotide substitutions, as well as deletions (del), insertions (ins), deletion-insertion (delins), and splice mutations. The G:C > A:T transition was subdivided into G:C > A:T at CpG and non-CpG sites. Each spectrum is shown in the pie graph as follows: G:C > A:T at CpG sites (blue), G:C > A:T at non-CpG sites (orange), A:T > G:C (gray), G:C > C:G (yellow), G:C > T:A (light blue), A:T > C:G (light green), A:T > T:A (dark blue), del (brown), delins (dark gray), ins (light brown), and splice mutations (light navy). The prevalence of G:C > A:T at non-CpG sites (orange) in diffuse-type GCs in Asia was significantly different from that in Eastern Europe (p < 0.05). * Statistically significant difference (p < 0.05).

Additional file 2: Supplementary Figure S2.TP53 mutation types in the intestinal and diffuse types of GC samples from Eastern Europe, China, and Japan (exon 4-8). The pie graphs show the percentages of the mutations, including missense (blue), nonsense (orange), and silent mutations (gray), deletions (del) (yellow), deletion-insertion (delins) (light blue), insertions (ins) (light green), and splice site mutations (dark blue) in TP53 in GC samples from Eastern Europe, China, and Japan. The prevalence of silent mutations (gray) in diffuse-type GCs was significantly different between Europe and Asia (P < 0.01). * Statistically significant difference (p < 0.05).

In the tumor microenvironment, tumor-infiltrating immune cells (TIICs) are a key component. Different types of TIICs play distinct roles. CD8+ T cells and natural killer (NK) cells could secrete soluble factors to hinder tumor cell growth, whereas regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs) release inhibitory factors to promote tumor growth and progression. In the meantime, a growing body of evidence illustrates that the balance between pro- and anti-tumor responses of TIICs is associated with the prognosis in the tumor microenvironment. Therefore, in order to boost anti-tumor response and improve the clinical outcome of tumor patients, a variety of anti-tumor strategies for targeting TIICs based on their respective functions have been developed and obtained good treatment benefits, including mainly immune checkpoint blockade (ICB), adoptive cell therapies (ACT), chimeric antigen receptor (CAR) T cells, and various monoclonal antibodies. In recent years, the tumor-specific features of immune cells are further investigated by various methods, such as using single-cell RNA sequencing (scRNA-seq), and the results indicate that these cells have diverse phenotypes in different types of tumors and emerge inconsistent therapeutic responses. Hence, we concluded the recent advances in tumor-infiltrating immune cells, including functions, prognostic values, and various immunotherapy strategies for each immune cell in different tumors.

The mechanical recycling method of the carbon fiber-reinforced polymer (CFRP) has the advantages of simple process, less pollution and low cost, but only low utilization value of carbon fibers in powder or short fibers form can be obtained. To reduce the length and strength loss of the recycled carbon fibers, a novel and cost-effective dimethylacetamide (DMAC) swelling technique was developed to achieve rapid delamination of the CFRP laminates under mild conditions (120°C–160°C, 1 h). The corresponding swelling ratios and mass-loss rates of cured epoxy resin (CEP) were about 121.39%–157.39% and 0–0.69%, respectively. Excessive swelling of CEP in DMAC resulted in the cracking of the resin matrix between the adjacent carbon fiber layers. Thus the CFRP laminates were delaminated into soft single carbon fiber layers, which showed excellent cutting performance and reinforcing properties. The delamination products were cut into thin strips of different sizes and vacuum bag molded into new CFRP laminates. The flexural strength and tensile strength of the newly produced CFRP laminates were about 76.38%–90.98% and 94.61%–98.54% of the original CFRP laminates, respectively. More importantly, the chemical compositions of DMAC and CEP were unchanged during the physical swelling process. No organic pollutants (caused by resin degradation) were generated. And the used DMAC can be easily recycled by filtration. Therefore, this study provides a strategy for low-cost and high-valued recycling of CFRP waste.

BackgroundThe Coronavirus disease 2019 (COVID-19) has presented a major challenge to the health, economic, and social sectors of the entire world. This study aimed to investigate the mental health and academic performance of medical postgraduates during the COVID-19 pandemic in China.MethodsA cross-sectional online survey was conducted from March 20 to April 20, 2022 at the Zhejiang University School of Medicine in China. The questionnaire consisted of three parts: general information, mental health and academic performance. Mental health outcomes were assessed according to the Generalized Anxiety Scale (GAD-7) and the Patient Health Questionnaire-9 Scale (PHQ-9).ResultsA total of 153 valid questionnaires were obtained. Of the medical postgraduates in this study, (1) 41.8% had no anxiety symptoms. In addition, 51.0% had mild anxiety symptoms during the COVID-19 pandemic. None of the participants had a severe anxiety or depression disorder; (2) Females experienced significantly more symptoms in mental health measure scores than the males (P < 0.01); (3) 78.4% believed that the COVID-19 pandemic had varying degrees of impact on their academics. Doctoral postgraduates showed greater academic stress, and they were more worried about not meeting graduation standards than the master's postgraduates (P < 0.05). There were no significant differences between the surgical postgraduates and internal postgraduates in either mental health or academic performance.ConclusionsOur study found that the COVID-19 pandemic has had a mild impact on the mental health and academic performance of medical postgraduates in China. Females experienced significantly more symptoms on mental health measure scores than the males. Doctoral postgraduates showed greater academic stress than the master's postgraduates. There is uncertainty regarding how long this COVID-19 situation will persist and increasing recognition that there may be periods of recurrence in the future. We need more active curricular innovation and transformation to maintain and improve medical postgraduates' mental health and academic performance.

Depression is one of most common psychiatric disorders, and the detailed molecular mechanism remains to be fully elucidated. Brain-derived neurotrophic factor (BDNF) is a critical neurotrophic factor that is decreased and closely involved in the development of depression. Noncoding RNAs are central regulators of cellular activities that modulate target genes. However, the roles of long noncoding RNA (lncRNA) MIR155HG and miRNA-155 (miR-155) in the pathophysiology of depression are unclear. In the present study, we aimed to explore the effects of lncRNA MIR155HG and miR-155 on the development of depression and uncover the underlying molecular mechanism. Real-time quantitative polymerase chain reaction was used to examine the expression of MIR155HG and miR-155. Western blotting was applied to measure the expression of BDNF. A luciferase reporter assay was utilized to determine the regulatory relationship between MIR155HG and miR-155. Our current work found that lncRNA MIR155HG and BDNF levels decreased while miR-155 levels increased in the hippocampal region of CUMS (chronic unpredictable mild stress) mice, a well-accepted mouse model of depression. Moreover, MIR155HG rescued while miR-155 exacerbated the depression-like behaviors of CUMS mice. Through bioinformatics analysis and luciferase reporter assays, we found that MIR155HG directly bound to and negatively modulated the expression of miR-155. Moreover, increased miR-155 was found to repress the expression of BDNF, a critical neurotrophic factor that has been reported to alleviate the depression-like behaviors of CUMS mice. Our present study revealed that lncRNA MIR155HG protected CUMS mice by regulating the miR-155/BDNF axis. Our study aimed to understand the pathophysiology of depression and provided potential therapeutic targets to diagnose and treat depression.

Torreya grandis is an important economic tree species in China. It provides nutritional value and is important to the health care industry. There are ongoing issues with product quality which are primarily related to improper management and early harvest. This study was carried out during the fruit ripening processes to evaluate the influence of harvesting date on T. grandis quality, and to determine the optimal harvest period. The effects of harvest time on the variation of quality and nutritional parameters of T. grandis nuts and its oil were evaluated, and the optimal harvest period was determined. The results showed that harvest timing had a strong effect on both oil yield and quality. Prolonged ripening could induce higher levels of kernel rate, fruit inclusions, oil and nutritional quality. When the sample harvested in the mid-September, the kernel rate and oil content were increased by 1.88±0.31% and 6.65±0.47%, respectively, compared to samples harvested in the beginning of late-August. Similarly, the mid-September harvest resulted in total unsaturated fatty acids content of the oil being increased by 5.3±0.34%, the FFA and peroxide value being decreased by 40.7±0.15% and 76±0.08%, respectively, and total tocopherols and free amino acids were increased 7.5±0.24% and 47.3±0.15%, respectively, compared to the samples harvested on Aug. 25. The results indicated that the optimal harvest time of T. grandis fruits was mid-September as it was beneficial for improving the quality of T. grandis nut and its oil. It was suggested that T. grandis fruit should be harvested later.

Melanoma is a deadly form of skin cancer with high rates of resistance to traditional chemotherapy and radiotherapy. BRAF inhibitors (BRAFi) can achieve initial efficacy when used to treat melanoma patients, but drug resistance and relapse are common, emphasizing the need for new therapeutic strategies. Herein, we reported that combination of dimethyl fumarate (DMF) and vemurafenib (Vem) inhibited melanoma cell proliferation more significantly and induced more cell death than single agent did both in vitro and in vivo. DMF/Vem treatment induced cell death through inhibiting the expression and transcriptional activity of NRF2 thereby resulting in more reactive oxygen species (ROS) and via inhibiting the expression of YAP, a key downstream effector of Hippo pathway. DMF/Vem treatment also reduced phosphorylation of AKT, 4EBP1, P70S6K and ERK in AKT/mTOR/ERK signaling pathways. RNA-seq analysis revealed that DMF/Vem treatment specifically suppressed 4561 genes which belong to dozens of cell signaling pathways. These results indicated that DMF/Vem treatment manifested an enhanced antitumor efficacy through inhibiting multiple cell signaling pathways, and thus would be a novel promising therapeutic approach targeted for melanoma.

Additional file 7: Table S5. Oligonucleotide sequences used in the study.

Additional file 1: Fig. S1. Whole-genome bisulfite sequencing of the FMO and TYO fish groups. A and B Pearson’s correlation analysis (A) and principal component analysis (B) of the six samples from the two groups. C and D Distribution of mCs in different genomic regions (C) and in different gene elements (D). E and F Methylation levels (E) and length distribution (F) of DMRs.

Additional file 3: Table S1. Methylated cytosines percentage of different context

Additional File 2: Fig. S2. Correlation between DNA methylation and gene expression (A) The methylation levels of different gene groups (with different mRNA expression levels) in the TYO group. B The mRNA expression levels of different gene categories (with different methylation levels) in the promoter region of the TYO group. C mRNA expression levels of different gene categories (with different methylation levels) in the gene body regions of the TYO group. D Correlation between DNA methylation levels and gene expression levels of promoter hyper-DMGs. E Correlation between DNA methylation levels and gene expression levels of gene body hypo-DMGs.

Additional file 1: Fig. S1. Clustered heatmap of yaks in different health status at the bacterial genus level. The color values of the heatmap indicate the normalized relative richness of each species. Fig. S2. Clustered heatmap of yaks in different health status at the fungal genus level. The color values of the heatmap indicate the normalized relative richness of each species. Fig. S3. The gut bacterial comparisons between healthy and diarrheic yaks in phylum and genus levels. Metastats analysis was applied to identify the significantly differentially abundant bacterial genera between both groups and all of the data represent means ± SD. * p

Additional file 1: Supplement Figure 1. Association between the lipophilic index and oral cancer by stratified analysis.

Additional file 2: Supplement Table 1. Multivariable generalized Linear Models of mediation of outcome models.

Background The characterization of colonization and dynamic changes related to gut microorganisms might be vital, as it presents an opportunity to quantify the co-variation between stocking densities and gut microbiome of dynamic distribution. The objective of this study was to determine the stocking density on physiological performance and dynamic distribution of gut microbiome (including bacterial and fungal communities) of Langya laying hens in the two development stages. Methods A randomized design with 2 × 3 factorial controls consisting of two development stages (24, 43 weeks-old) with three different stocking densities was performed. Three different stocking densities were allocated to a total of 300 11-week-old Langya laying hens (450 cm2/bird, 675 cm2/bird, 900 cm2/bird). Three housing densities were accomplished by raising different chickens per cage with the same floor size. The dependent variables of stocking densities at each sampling point were; growth performance, organs index, egg quality and the changes of dynamic gut bacterial and fungal communities in the cecum. Results Results showed that the stocking density didn’t affect liver index, eggshell thickness, breaking shell strength and egg shape index. Hens from the highest stocking density had the lowest body weight, fallopian tube index, egg weight and yolk colour score. Except for the yolk colour score, the measurement changes caused by age followed the opposite pattern as stocking density. We observed a substantial rise in taxa linked with health threats when stocking density was increased, including Talaromyces, Oscillospiraceae_UCG-002, Oscillospira, and Dielma. The opposite was observed with Bacteroides, Bifidobacterium, Lachnoclostridium, Eisenbergiella, and Kurtzmaniella. Also, most taxa were linked to polymicrobial infection in clinical cases, especially species whose percentage declined as the hens aged, such as Terrisporobacter, Faecalicoccus, Dialister, Cylindrocarpon etc. Whereas Sellimonas, Mitsuokella, Eurotium, Wardomyces and Cephalotheca had the opposite trend. Conclusion We speculated that excessive high density drove the abundance of bacteria and fungi connected with health problems. Where the gut microecology gradually reach a mature and balance status with age. Overall, this study demonstrates gut microbiome ecological processes in Langya layers at various stocking densities and finds possible connections between stocking density, microbiome and production performance. Our study will contribute to new insights associating suitable density patterns and production performance in laying hens by harnessing such a relative microbiome.

Chitin is a linear homopolymer of acetylated β-(1,4)-linked glucosamine residues and among the most abundant polysaccharides in the world. Here, we identified and purified a novel chitosanase (CCHA) from Aspergillus oryzae NKY2017 obtained from Hu’bei province in China. Construction of a cDNA library from this strain revealed the gene sequence subsequently expressed in Pichia pastoris and subsequent construction of multi-copy expression plasmids (CCHA1/2/3/4). The results demonstrated elevated levels of CCHA expression in multi-copy strains, with strain CCHA4 chosen for high-density fermentation and enzyme-activity experiments. High-density fermentation achieved a CCHA yield of 22,500 U/mL, and temperature and pH optimization resulted in the highest CCHA activity at 40°C and 4.0, respectively. We used this enzyme for a large-scale preparation of oligosaccharides: 4 g enzyme could convert 150 kg chitosan into oligosaccharides in 24 h at 40°C. These results demonstrated abundant CCHA expression in P. pastoris and suggested the efficacy of CCHA for use in industrial applications.

Two hypotheses for the blocking effect mechanisms under the electromagnetic radiation are presented, and the corresponding dual-frequency interference prediction models are proposed, which can be used to predict the working state of equipment under the condition that the single-frequency susceptibility is known. By taking a radar and a communication radio as the EUT, the experiments of dual-frequency continuous wave electromagnetic radiation are designed and carried out to verify the prediction models. The test results show that the sensitive bandwidth of blocking interference effect for the tested radar and the communication station is consistent with their working bandwidth, respectively. By substituting the test data into the proposed prediction models, the prediction errors of the models are less than 13%. Moreover, it can be found that the tested radar is more sensitive to the peak value of electric field, and the tested communication station is more sensitive to the effective value of electric field.

Data used for the plots and tables can be found. The data are saved as matlab data file. 1)burst characteristics.matis used for producing figures 10. 2)Heffects.matis used for producing figures 8. 3)tidal_contributions.matis used for producing figure9. 4)timeseries.matis used for producing figures 5, 6 and 7. 5)profile_timeseries.matis used for producing figures 4.

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultra-peripheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of $J/\psi$ photoproduction off the deuteron in UPCs at the center-of-mass energy $\sqrt{s_{_{\rm NN}}}=200~\rm GeV$ in d$+$Au collisions. The differential cross section as a function of momentum transfer $-t$ is measured. In addition, data with a neutron tagged in the deuteron-going Zero-Degree Calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the Color Glass Condensate saturation model and the gluon shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup, which provides insights into the nuclear gluonic structure., Comment: Final published version Phys. Rev. Lett. 128, 122303

L-amino acid oxidase (AAO) was reported to be capable of converting L-glutamic acid to α-aketoglutaric acid (α-KG). The sequence of AAO from Kitasatospora cheerisanensis was synthesized based on Pichia pastoris codon-usage preferences. AAO gene was cloned into plasmid pPICZα which was transformed into P. pastoris. Next, multi-copy expression plasmids were constructed by using plasmid pHBM905BDM. High-density fermentation was performed and the recombinant enzyme was characterized. The conversion conditions were optimized. By using Escherichia coli expression system, no soluble or active AAO was obtained from two strains after fermentation and induction. We can’t obtain high-level expression of recombinant strains by using plasmid pPICZα. Therefore, we constructed multi-copy expression plasmids using plasmid pHBM905BDM. By using this plasmid, multi-copy strains were constructed and named as PAAO1, PAAO2, PAAO3, PAAO4, and PAAO5, respectively. The following results showed that expression of AAO in multicopy strains increased as designed and strain PAAO5 was chosen for high-density fermentation and enzyme activity experiments. After high-density fermentation, we achieved an AAO-expression yield of 120.8 U/mL. After temperature and pH optimization, the highest AAO activity was observed at a temperature and pH of 20°C and 6, respectively. After optimization of the conversion conditions, the average production rate of L-glutamic acid to α-KG was 3.46 g/L/h and the highest α-KG titer (103 g/L) was converted from 120 g/L L-glutamic acid. In this study, AAO was abundantly expressed by using P. pastoris expression system. The following experiments indicated that AAO is suitable for use in industrial applications.

Additional file 1. Supplementary materials of the full text, including of Table S1: The design of primers in six different amino acid sites; Figure S1: Thin-layer chromatography (TLC) to evaluate catalytic activities of the mutants for α-ketobutyric acid; Figure S2: SDS-PAGE to analyze the purified mutant protein. Figure S3: The concentration of L-2-Aminobutyric acid was detected by HPLC; Figure S4: Chiral analysis of aminobutyric acid; Figure S5: Enzyme kinetic curve of ω-transaminase.

Additional file 2. Additional methods.

Additional file 2. Raw materials of the full text, containing the original, unprocessed and uncropped version of the table 1, Fig 2 and Fig 5 in manuscript. The schematic view of the pET28 plasmid as well as the designed gene structure in assay.

Additional file 2: [44]

Additional file 1

Additional file 1. Additional tables.

Pure W, and W–0.5wt%ZrC (WZC) and W–2.0wt%Zr–0.5wt%ZrC (WZZC) alloys are fabricated using vacuum hot pressure (VHP) method to investigate the effects of trace ZrC or Zr/ZrC on the mechanical properties and microstructure of tungsten. It was found that from W to WZC and to WZZC, the average grain size was refined from 6.2 µm of W to 5.8 μm of WZC and finally to 4.8 um for WZZC and relative density increase continually from 97.0% to 98.0% and to 98.5%. The tensile tests indicated that ZrC or ZrC/Zr significantly increases the strength and ductility/plasticity. The comparison of VHPed and spark plasma sintered (SPSed) specimen are made. The microstructure analysis indicate that the W–Zr–O and/or Zr–C–O particles resulting from the reaction of Zr or ZrC with free O pin grain boundaries (GBs) of tungsten and inhibits the migration of GBs, and then refining the grain size. The synergistic effects of the decrease of free O impurity and nano-sized ZrC dispersion strengthening strengthen GBs and improve the mechanical properties. Keywords: Tungsten, Trace Zr/ZrC, Mechanical property, Microstructure

HIGHLIGHTS The antifungal effect of the active substance in camellia seed cake is evaluated on Aspergillus flavus. The n-butanol phase exhibited an apparent antagonistic effect on A. flavus. A reference and a guide for natural antifungal agents is provided. Knowledge of the utilization of the by-products of camellia seed is broadened.

Background DNA polymerases are important enzymes that synthesize DNA molecules and therefore are critical to various scientific fields as essential components of in vitro DNA synthesis reactions, including PCR. Modern diagnostics, molecular biology, and genetic engineering require DNA polymerases with improved performance. This study aimed to obtain and characterize a new CL7-Taq fusion DNA polymerase, in which the DNA coding sequence of Taq DNA polymerase was fused with that of CL7, a double-stranded DNA binding-like protein from Escherichia coli. Results The resulting novel recombinant gene was cloned and expressed in E. coli. The recombinant CL7-Taq protein exhibited excellent thermostability, extension rate, sensitivity, and resistance to PCR inhibitors. Our results showed that the sensitivity of CL7-Taq DNA polymerase was 100-fold higher than that of wild-type Taq, which required a template concentration of at least 1.8 × 105 aM. Moreover, the extension rate of CL7-Taq was 4 kb/min, which remarkably exceeded the rate of Taq DNA polymerase (2 kb/min). Furthermore, the CL7 fusion protein showed increased resistance to inhibitors of DNA amplification, including lactoferrin, heparin, and blood. Single-cope human genomic targets were readily available from whole blood, and pretreatment to purify the template DNA was not required. Conclusions Thus, this is a novel enzyme that improved the properties of Taq DNA polymerase, and thus may have wide application in molecular biology and diagnostics.

Background Nattokinase is a fibrinolytic enzyme that has huge market value as a nutritional supplement for health promotion. In order to increase nattokinase yields, fermentation conditions, strains, cultivation media, and feeding strategies have been optimized. Nattokinase has been expressed using several heterologous expression systems. Pichia pastoris heterologous expression system was the alternative. Results This report aimed to express high levels of nattokinase from B. subtilis natto (NK-Bs) using a Pichia pastoris heterologous expression system and assess its fibrinolytic activity in vivo. Multicopy expression strains bearing 1–7 copies of the aprN gene were constructed. The expression level of the target protein reached a maximum at five copies of the target gene. However, multicopy expression strains were not stable in shake-flask or high-density fermentation, causing significant differences in the yield of the target protein among batches. Therefore, P. pastoris bearing a single copy of aprN was used in shake-flask and high-density fermentation. Target protein yield was 320 mg/L in shake-flask fermentation and approximately 9.5 g/L in high-density fermentation. The recombinant nattokinase showed high thermo- and pH-stability. The present study also demonstrated that recombinant NK-Bs had obvious thrombolytic activity. Conclusions This study suggests that the P. pastoris expression system is an ideal platform for the large-scale, low-cost preparation of nattokinase.

Methyl parathion hydrolase (MPH) hydrolyses methyl parathion efficiently and specifically. Herein, we produced MPH from Plesiomonas sp. M6 using a Pichia pastoris multi-copy expression system. The original signal peptide sequence of the target gene was removed, and a modified coding sequence was synthesised. Multi-copy expression plasmids containing MPH were constructed using pHBM905BDM, and used to generate recombinant strains containing 1, 2, 3 or 4 copies of the MPH gene. The results showed that a higher target gene copy number increased the production of recombinant MPH (MPH-R), as anticipated. The expression level of the recombinant strain containing four copies of the MPH gene was increased to 1.9 U/ml using 500 ml shake flasks, and the specific activity was 15.8 U/mg. High-density fermentation further increased the target protein yield to 18.4 U/ml. Several metal ions were tested as additives, and Ni2+, Co2+ and Mg2+ at a concentration of 1 mM enhanced MPH-R activity by 196%, 201% and 154%, respectively. Enzyme immobilisation was then applied to overcome the difficulties in recovery, recycling and long-term stability associated with the free enzyme. Immobilised MPH-R exhibited significantly enhanced thermal and long-term stability, as well as broad pH adaptability. In the presence of inhibitors and chelating agents such as sodium dodecyl sulphate (SDS), immobilised MPH-R displayed 2-fold higher activity than free MPH-R, demonstrating its potential for industrial application.

Pseudomonas protegens SN15-2, a typical non-spore-forming rhizosphere bacterium, has excellent biocontrol capabilities; thus, it is necessary to explore the stress resistance of SN15-2. The choline-glycine betaine pathway is considered as an important mechanism by which bacteria adapt to stressful environments. In this work, we demonstrated that the expression of the betA and betB genes, which are involved in the choline- glycine betaine pathway in SN15-2, was highly increased by 12-fold and 26-fold, respectively, by hyperosmotic stress and choline treatment. The accumulation of betaine in SN15-2 (5.54 g/L) was significantly higher than that in the mutants Δ betA (3.44 g/L) and Δ betB (2.68 g/L) under hyperosmotic stress and choline treatment. Moreover, choline enhanced the growth of SN15-2 greatly, but it did not enhance the growth of Δ betB under hyperosmotic stress. Choline combined with hyperosmotic adaptation significantly increased the lethal stress resistance of SN15-2 while the resistance of Δ betA and Δ betB was significantly decreased. This research illuminated a strategy underlying the adaptation to osmotic stress in P. protegens and provided an effective method to improve the stress resistance of this species, thus provided a theoretical basis for the practical application of P. protegens SN15-2.

The deep combination of information technology and education has provided a complete technical support and deep foundation for smart education. With the advent of 5G, the smart learning environment based on the smart education system will be greatly developed. This paper presents the concepts and technical characteristics of 5G, explains the content of smart learning environment, analyzes the technical composition of smart learning environment in the context of 5G, and probes into the challenges faced by smart learning environment in 5G environment. The purpose of this paper is to provide new ideas for creating a smart learning environment in the context of 5G.

BackgroundAntiviral therapies against the novel coronavirus SARS-CoV-2, which has caused a global pandemic of respiratory illness called COVID-19, are still lacking.MethodsOur study (NCT04252885, named ELACOI), was an exploratory randomized (2:2:1) controlled trial assessing the efficacy and safety of lopinavir/ritonavir (LPV/r) or arbidol monotherapy for treating patients with mild/moderate COVID-19.FindingsThis study successfully enrolled 86 patients with mild/moderate COVID-19 with 34 randomly assigned to receive LPV/r, 35 to arbidol and 17 with no antiviral medication as control. Baseline characteristics of the three groups were comparable. The primary endpoints, the average time of positive-to-negative conversion of SARS-CoV-2 nucleic acid and conversion rates at days 7 and 14, were similar between groups (all P>0.05). There were no differences between groups in the secondary endpoints, the rates of antipyresis, cough alleviation, or improvement of chest CT at days 7 or 14 (all P>0.05). At day 7, eight (23.5%) patients in the LPV/r group, 3 (8.6%) in the arbidol group and 2(11.8%) in the control group showed a deterioration in clinical status from moderate to severe/critical(P =0.206). Overall, 12 (35.3%) patients in the LPV/r group and 5 (14.3%) in the arbidol group experienced adverse events during the follow-up period. No apparent adverse event occurred in the control group.ConclusionsLPV/r or arbidol monotherapy present little benefit for improving the clinical outcome of patients hospitalized with mild/moderate COVID-19 over supportive care.FundingThis study was supported by project 2018ZX10302103-002, 2017ZX10202102-003-004 and Infectious Disease Specialty of Guangzhou High-level Clinical Key Specialty (2019-2021).

Feature extraction is one of the challenging problems in fault diagnosis, and it has a direct bearing on the accuracy of fault diagnosis. Therefore, in this paper, a new method based on ensemble empirical mode decomposition (EEMD), wavelet semi-soft threshold (WSST) signal reconstruction, and multi-scale entropy (MSE) is proposed. First, the EEMD method is applied to decompose the vibration signal into intrinsic mode functions (IMFs), and then, the high-frequency IMFs, which contain more noise information, are screened by the Pearson correlation coefficient. Then, the WSST method is applied for denoising the high-frequency part of the signal to reconstruct the signal. Secondly, the MSE method is applied for calculating the MSE values of the reconstructed signal, to construct an eigenvector with the complexity measure. Finally, the eigenvector is input to a support vector machine (SVM) to find the fault diagnosis results. The experimental results prove that the proposed method, with a better classification performance, can better solve the problem of the effective signal and noise mixed in high-frequency signals. Based on the proposed method, the fault types can be accurately identified with an average classification accuracy of 100%.

Engineering practice education is an important contents of education and teaching in mechanical specialty, and experimental teaching plays a vital role in acquiring a better understanding of the theoretical knowledge of the course and cultivating their engineering practice ability for students. However, due to the low correlation of the experimental content of each course, causing the discretization of knowledge system, which is not conducive for system to cultivate students' practical ability, and at the same time, it also affects students' learning initiative. To solve this problem, taking the comprehensive experiment of numerical control technology and tool angle measurement as an example, the experimental platform and experimental teaching link based on multidisciplinary knowledge fusion are designed, which can integrate the experimental contents of related courses in mechanical engineering well, and that can enable students to master related knowledge in mechanical engineering systematically and cultivate engineering practical ability. At the same time, it can also change students' learning styles from passive to active, and better improve students' ability to solve complex mechanical engineering problems.

At present, a new round of scientific and technological revolution and industrial transformation are accelerating worldwide. The new economy characterized by new technology, new forms of business and new industry is developing vigorously. This requires engineering scientific and technological talents to have higher innovation and entrepreneurship ability and cross-border integration ability, which poses new challenges to the reform and development of high education. The construction of Emerging New Education is the response to this challenge. Based on this, this paper analyses and studies the objectives, main contents and main measures of teaching reform of Emerging New Education construction of mechanical specialty, and puts forward a training mode of outstanding and innovative talents of mechanical specialty for the construction of Emerging New Education, with a view to providing reference for the construction of Emerging New Education in colleges and universities.

Flower senescence is classified into ethylene-dependent and ethylene-independent manners and determines the flower longevity which is valuable for ornamental plants. However, the manner of petal senescence in tulip is still less defined. In this study, we characterized the physiological indexes in the process of petal senescence, as well as metabolic and ethylene responses in tulip cultivar 'American Dream', and further identified the role of ethylene biosynthesis genes TgACS by transgenic and transient assays. Primary metabolites profiling revealed that sugars, amino acids and organic acids preferentially accumulated in senescent petals. Additionally, senescence-associated genes were identified and significantly up-regulated, coupled with increased ROS contents, rapid water loss and accelerated cell membrane breakdown. Moreover, ethylene production was stimulated as evidenced by increasing in ACS activity and ethylene biosynthesis-related genes expression. Exogenous treatment of cutting flowers with 1-MCP or ethephon resulted in delayed or enhanced petal senescence, respectively. Transient down-regulation of TgACS by VIGS assay in tulip petals delayed senescence, while over-expressed TgACS1 in tobacco promoted leaf senescence. Taken together, this study provides evidences to certify ethylene roles and TgACS functions during flower senescence in tulip.

Objective High altitude pulmonary edema (HAPE) is a life threatening condition occurring in otherwise healthy individuals who rapidly ascend to high altitude. However, the molecular mechanisms of its pathophysiology are not well understood. The objective of this study is to evaluate differential gene expression in patients with HAPE during acute illness and subsequent recovery. Methods Twenty-one individuals who ascended to an altitude of 3780 m were studied, including 12 patients who developed HAPE and 9 matched controls without HAPE. Whole-blood samples were collected during acute illness and subsequent recovery for analysis of the expression of hypoxia-related genes, and physiologic and laboratory parameters, including mean pulmonary arterial pressure (mPAP), heart rate, blood pressure, and arterial oxygen saturation (SpO2), were also measured. Results Compared with control subjects, numerous hypoxia-related genes were up-regulated in patients with acute HAPE. Gene network analyses suggested that HIF-1α played a central role in acute HAPE by affecting a variety of hypoxia-related genes, including BNIP3L, VEGFA, ANGPTL4 and EGLN1. Transcriptomic profiling revealed the expression of most HAPE-induced genes was restored to a normal level during the recovery phase except some key hypoxia response factors, such asBNIP3L, EGR1, MMP9 and VEGF, which remained persistently elevated. Conclusions Differential expression analysis of hypoxia-related genes revealed distinct molecular signatures of HAPE during acute and recovery phases. This study may help us to better understand HAPE pathogenesis and putative targets for further investigation and therapeutic intervention.