The Relationship Between the hOGG1 rs1052133 Polymorphism and the Occurrence of Nasopharyngeal Carcinoma: A Systematic Review and Meta-Analysis.

Objectives: Exploring the relationship between the hOGG1 rs1052133 polymorphism and the occurrence of nasopharyngeal carcinoma (NPC). Methods: PubMed, Web of Science, Scopus, CNKI, Wanfangdata, and VIP were used to search for studies and the NOS evaluation scale was used to evaluate the quality. All studies were grouped according to different genotypes. The Cochrane's Q test and I2 test were used for heterogeneity evaluations. If heterogeneity was small, the fixed effects model was used, and conversely, the random effects model was used. Publication bias was also detected. P < .05 in all results indicated statistically significant. Results: We ultimately included 6 studies with 2021 NPC patients in the study group and 2375 healthy populations in the control group. After meta-analysis, it was found that the total OR value of the "Ser/Cys (CG) vs Ser/Ser (CC)" group was 1.00 (95% CI: 0.85-1.18) and the "Cys/Cys (GG) vs Ser/Ser (CC)" group was 1.06 (95% CI: 0.87-1.28). These results were not statistically significant (P > .05). Furthermore, the integrated total OR values of each group were not statistically significant with or without the smoking history, even in other genotype models (Allele, Dominant, Recessive, and Additive) (P > .05). Conclusion: There is no clear correlation between the hOGG1 rs1052133 polymorphism and the occurrence of NPC, even with or without the smoking history.

Preparation, structural analysis of alcohol aroma compounds/ß-cyclodextrin inclusion complexes and the application in strawberry preservation.

The dynamic combination of aromas and cyclodextrins is an important means to achieve their stability and controllability, and accurately revealing their interaction rules is the key to designing and constructing high-quality aroma nanocarriers. In this study, the inclusion mechanism between alcohol aroma compounds with different structures and ß-cyclodextrin (ß-CD) was studied by combining molecular dynamics simulation and experimental methods. Results showed that the selected alcohol aroma compounds formed inclusion complexes (ICs) with ß-CD in a 1:1 ratio, while alcohol aroma compounds containing cyclic structures were more tightly bound to ß-CD. Van der Waals forces were the primary forces driving the formation and stabilization of the ICs. Cinnamyl alcohol/ß-CD ICs showed the most significant antimicrobial effect and notably prolonged the shelf life of strawberries. This study aimed to provide theoretical support for precisely designing and preparing highly stable flavours and fragrances, as well as expanding their application range.

Scalable and Effective Temporal Graph Representation Learning With Hyperbolic Geometry.

Real-life graphs often exhibit intricate dynamics that evolve continuously over time. To effectively represent continuous-time dynamic graphs (CTDGs), various temporal graph neural networks (TGNNs) have been developed to model their dynamics and topological structures in Euclidean space. Despite their notable achievements, the performance of Euclidean-based TGNNs is limited and bounded by the representation capabilities of Euclidean geometry, particularly for complex graphs with hierarchical and power-law structures. This is because Euclidean space does not have enough room (its volume grows polynomially with respect to radius) to learn hierarchical structures that expand exponentially. As a result, this leads to high-distortion embeddings and suboptimal temporal graph representations. To break the limitations and enhance the representation capabilities of TGNNs, in this article, we propose a scalable and effective TGNN with hyperbolic geometries for CTDG representation (called STGNh ). It captures evolving behaviors and stores hierarchical structures simultaneously by integrating a memory-based module and a structure-based module into a unified framework, which can scale to billion-scale graphs. Concretely, a simple hyperbolic update gate (HuG) is designed as the memory-based module to store temporal dynamics efficiently; for the structure-based module, we propose an effective hyperbolic temporal Transformer (HyT) model to capture complex graph structures and generate up-to-date node embeddings. Extensive experimental results on a variety of medium-scale and billion-scale graphs demonstrate the superiority of the proposed STGNh for CTDG representation, as it significantly outperforms baselines in various downstream tasks.

The shape of the Himalayan "Arc": An Ellipse pinned by syntaxial strike-slip fault tips.

Trans-Himalayan geodetic data show that, between both syntaxes, India/Asia convergence is steadily oriented ≈ N20°E. However, surface faulting near both syntaxes, along the 2005 and 1950 earthquake ruptures, imply long-term thrusting directed ≈ 130° apart, and post-LGM (last Glacial Maximum) shortening rates of ≈ 5 to 6 mm/y, ≈ 2 to 3 times slower than in Nepal (≈ 15 to 20 mm/y). Syntaxial earthquakes' return-time are also ≈ 3 times longer (>2,000 y) than in Nepal (≈ 700 y). In a structural frame centered halfway between the syntaxial cusps, the tectonic features of the range show remarkable symmetry. In map view, the overall shapes of the Main Front Thrust (MFT) and the Main Central Thrust (MCT) closely fit ellipses, with major-to-minor axis ratios of ≈ 2.5 to 3. This suggests that the range growth atop subducting India is "pinned" by the strike-slip faults that bound it to the east and west. Discrete Element Modeling corroborates a late-Tertiary elliptical range growth. This accounts for the ≈ 65° angles and twofold to threefold decrease in active thrusting between Nepal and the syntaxes, for the maximum Himalayan heights (≥8,000 m), larger magnitudes (≥8), and shorter return-time (≈ 700 y) of great earthquakes in Nepal, for the existence of two 500- to 600 km-long, south-concave mountain ranges north of both syntaxes and for the ≈ 9 mm/y, N100 to 110°E extension across southern Tibet. It also suggests that predictions of impending or frequent great earthquakes in the eastern- and westernmost Himalayas may be overstated.

Amino acid-based enteral nutrition is effective for pediatric Crohn's disease: a multicenter prospective study.

Background: Exclusive enteral nutrition (EEN) therapy effectively induces remission in pediatric Crohn's disease (CD). However, this may depend on the type of enteral formula used. Moreover, data on the efficacy of amino acid-based EEN are limited. Thus, we aimed to prospectively evaluate the efficacy of amino acid-based formulas for EEN in pediatric patients with active CD. Methods: Patients with active CD aged between 6 and 17 years were recruited into this prospective study from four hospitals in China between March 2019 and December 2021. Patients received EEN for 8 weeks. Inflammatory and nutrition-associated indices were evaluated at 0, 4, and 8 weeks after treatment. Paired t-tests and Wilcoxon signed-rank tests were used to compare continuous and categorical variables before and after intervention, respectively. Results: Twenty-four patients were included in the analysis. After an 8-week intervention period, the CD activity index significantly decreased (26.3 ± 12.2 vs 7.1 ± 8.3, P < 0.001). Most patients (66.7%) achieved complete clinical remission. Among the 22 patients who had ulcers and erosions diagnosed endoscopically at baseline, 10 (45.5%) achieved complete mucosal healing. The degree of thickening of the intestinal wall was significantly reduced after EEN intervention, with a transmural healing rate of 42.9%. Furthermore, the serum inflammatory markers decreased and there was a significant improvement in the nutrition-related indices (P < 0.05). There were no severe adverse effects. Conclusions: Amino acid-based EEN is effective and safe for treating pediatric-onset CD. Studies with larger sample sizes and mechanistic and follow-up studies are required to further validate these findings.

Novel supramolecular deep eutectic solvent pretreatment for obtaining fluorescent lignin and promoting biomass pyrolytic saccharification.

In this study, ß-CD was used as a receptor to prepare three novel SDES, which were used to pretreat corn stalks for obtaining fluorescent lignin and promoting biomass pyrolytic saccharification. It was found that GA-residue had a high cellulose retention ratio (94.63%) and the highest lignin removal ratio (61.78%). Besides, the yield of carbohydrates in bio-oil was increased from 0.63% to 49.37%, and fluorescent lignin was prepared for explosion detection, fluorescent film, and information encryption. It was confirmed that the weak interaction between ß-CD and HBDs or dimer was mainly performed by hydrogen bond and van der Waals force. The minimum frontier orbital energy difference ΔEU (0.1976 a.u.) and high binding energy (-5456.71 kJ/mol) between molecules were calculated by DFT. Moreover, the mechanism of biomass pretreatment was explored. The green and efficient SDES developed in this study were of great significance for biomass pretreatment and efficient utilization of components.

Efficacy of apatinib combined with temozolomide in the treatment of recurrent high­grade glioma: A meta­analysis.

Recurrent high-grade glioma is a refractory disease, and its prognosis is poor. Although the treatment of apatinib combined with temozolomide provides improved efficacy and is able to prolong survival, this conclusion has been based on small samples. In order to clarify this treatment's efficacy, a meta-analysis was performed in the present study. Different databases were screened and finally, 10 studies were included, comprising 357 patients with recurrent high-grade gliomas. The efficacy and prognosis were analyzed using Stata software. The results indicated that the overall objective response rate (ORR) and disease control rate (DCR) of apatinib combined with temozolomide were 0.36 (95% CI, 0.26-0.46) and 0.86 (95% CI, 0.82-0.89), respectively. Subgroup analysis indicated that the overall ORR was 0.43 (95% CI, 0.29-0.57) and 0.26 (95% CI, 0.14-0.38), and the DCR was 0.89 (95% CI, 0.85-0.93) and 0.76 (95% CI, 0.69-0.84) in the treatment of apatinib with temozolomide dose-dense group and the conventional-dose group (5/28 regimen), respectively. Further prognostic analysis indicated that the median overall survival of patients with high-grade glioma treated with apatinib combined with temozolomide was 8.21 months (95% CI, 7.20-9.22 months) and the median progression-free survival was 5.45 months (95% CI, 4.53-6.37). Analysis of the publication bias of the effect size revealed that there was bias in the DCR, while no bias was found in the remaining effect size (ORR, median overall survival and median progression-free survival). After correction by the trim-and-fill method, bias was indicated to have no significant impact on the results. In conclusion, apatinib combined with temozolomide has the effect that, compared with traditional Bevacizumab treatment, it can improve the efficacy in the treatment of recurrent high-grade glioma and improve prognosis. When combining with dose-dense temozolomide, the effect may be better than that of the conventional 5/28 regimen.

Diagnostic Value of Dynamic 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (18F-FDG PET-CT) in Cervical Lymph Node Metastasis of Nasopharyngeal Cancer.

BACKGROUND AND PURPOSE: Dynamic 18F-FDG PET-CT scanning can accurately quantify 18F-FDG uptake and has been successfully applied in diagnosing and evaluating therapeutic effects in various malignant tumors. There is no conclusion as to whether it can accurately distinguish benign and malignant lymph nodes in nasopharyngeal cancer. The main purpose of this study is to reveal the diagnostic value of dynamic PET-CT in cervical lymph node metastasis of nasopharyngeal cancer through analysis. METHOD: We first searched for cervical lymph nodes interested in static PET-CT, measured their SUV-Max values, and found the corresponding lymph nodes in magnetic resonance images before and after treatment. The valid or invalid groups were included according to the changes in lymph node size before and after treatment. If the change in the product of the maximum diameter and maximum vertical transverse diameter of the lymph node before and after treatment was greater than or equal to 50%, they would be included in the valid group. If the change was less than 50%, they would be included in the invalid group. Their Ki values were measured on dynamic PET-CT and compared under different conditions. Then, we conducted a correlation analysis between various factors and Ki values. Finally, diagnostic tests were conducted to compare the sensitivity and specificity of Ki and SUV-Max. RESULT: We included 67 cervical lymph nodes from different regions of 51 nasopharyngeal cancer patients and divided them into valid and invalid groups based on changes before treatment. The valid group included 50 lymph nodes, while the invalid group included 17. There wer significant differences (p < 0.001) between the valid and the invalid groups in SUV-Max, Ki-Mean, and Ki-Max values. When the SUV-Max was ≤4.5, there was no significant difference in the Ki-Mean and Ki-Max between the two groups (p > 0.05). When the SUV-Max was ≤4.5 and pre-treatment lymph nodes were <1.0 cm, the valid group had significantly higher Ki-Mean (0.00910) and Ki-Maximum (0.01004) values than the invalid group (Ki-Mean = 0.00716, Ki-Max = 0.00767) (p < 0.05). When the SUV-Max was ≤4.5, the pre-treatment lymph nodes < 1.0 cm, and the EBV DNA replication normal, Ki-Mean (0.01060) and Ki-Max (0.01149) in the valid group were still significantly higher than the invalid group (Ki-Mean = 0.00670, Ki-Max = 0.00719) (p < 0.05). The correlation analysis between different factors (SUV-Max, T-stage, normal EB virus DNA replication, age, and pre-treatment lymph node < 1.0 cm) and the Ki value showed that SUV-Max and a pre-treatment lymph node < 1.0 cm were related to Ki-Mean and Ki-Max. Diagnostic testing was conducted; the AUC value of the SUV-Max value was 0.8259 (95% confidence interval: 0.7296-0.9222), the AUC value of the Ki-Mean was 0.8759 (95% confidence interval: 0.7950-0.9567), and the AUC value of the Ki-Max was 0.8859 (95% confidence interval: 0.8089-0.9629). After comparison, it was found that there was no significant difference in AUC values between Ki-Mean and SUV-Max (p = 0.220 > 0.05), and there was also no significant difference in AUC values between Ki max and SUV-Max (p = 0.159 > 0.05). By calculating the Youden index, we identified the optimal cut-off value. It was found that the sensitivity of SUV-Max was 100% and the specificity was 66%, the sensitivity of Ki-Mean was 100% and the specificity was 70%, and the sensitivity of Ki-Max was 100% and the specificity was 72%. After Chi-Square analysis, it was found that there was no significant difference in specificity between Ki-Mean and SUV-Max (p = 0.712), and there was also no significant difference in specificity between Ki-Max and SUV-Max (p = 0.755). CONCLUSION: Dynamic PET-CT has shown a significant diagnostic value in diagnosing cervical lymph node metastasis of nasopharyngeal cancer, especially for the small SUV value, and lymph nodes do not meet the metastasis criteria before treatment, and EBV DNA replication is normal. Although the diagnostic accuracy, sensitivity, and specificity of dynamic PET-CT were not significantly different from traditional static PET-CT, the dynamic PET-CT had a more accurate tendency.

In-situ forming dynamic covalently crosslinked nanofibers with one-pot closed-loop recyclability.

Polymeric nanofibers are attractive nanomaterials owing to their high surface-area-to-volume ratio and superior flexibility. However, a difficult choice between durability and recyclability continues to hamper efforts to design new polymeric nanofibers. Herein, we integrate the concept of covalent adaptable networks (CANs) to produce a class of nanofibers ⎯ referred to dynamic covalently crosslinked nanofibers (DCCNFs) via electrospinning systems with viscosity modulation and in-situ crosslinking. The developed DCCNFs possess homogeneous morphology, flexibility, mechanical robustness, and creep resistance, as well as good thermal and solvent stability. Moreover, to solve the inevitable issues of performance degradation and crack of nanofibrous membranes, DCCNF membranes can be one-pot closed-loop recycled or welded through thermal-reversible Diels-Alder reaction. This study may unlock strategies to fabricate the next generation nanofibers with recyclable features and consistently high performance via dynamic covalent chemistry for intelligent and sustainable applications.

The valuable role of dynamic 18F FDG PET/CT-derived kinetic parameter Ki in patients with nasopharyngeal carcinoma prior to radiotherapy: A prospective study.

BACKGROUND AND PURPOSE: Dynamic positron emission tomography/computed tomography (PET/CT) served the potential role of characterizing malignant foci. The main objective of this prospective study was to explore the advantage of dynamic PET/CT imaging in characterizing nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: Patients with probable head and neck disease underwent a local dynamic PET/CT scan followed by a whole-body static scan. Patlak analysis was used to generate parametric influx rate constant (Ki) images from 48 frames obtained from a dynamic PET/CT scan. By delineating the volumes-of-interest (VOIs) of: primary tumor (PT), lymph node (LN), and normal nasopharyngeal tissues (N), we acquired the corresponding Ki mean and SUVmean of each site respectively to perform the quantitative statistical analysis. RESULTS: Qualified images of 71 patients with newly diagnosed NPC and 8 without nasopharyngeal malignant lesions were finally included. We found the correlations between Ki mean-PT and critical clinical features, including clinical stage (r = 0.368), T category (r = 0.643) and EBV-DNA copy status (r = 0.351), and Ki mean-PT differed within the group. SUVmean-PT showed correlations with clinical stage (r = 0.280) and T category (r = 0.472), but could hardly differ systematically within group of clinical features except T category. Ki mean-LN offered the positive correlations with N category (r = 0.294), M category (r = 0.238) and EBV-DNA copy status (r = 0.446), and differed within the group. In addition, Ki mean represented a sensitivity of 94.4 % and a specificity of 100 %, in distinguishing NPC from the non-NPC, when the cut-off was defined as 0.0106. When the cut-off of SUV being defined as 2.03, the sensitivity and specificity were both 100 %. CONCLUSION: Our research confirmed Ki compared favorably to SUV in characterizing NPC and found that Ki can serve as an effective imaging marker of NPC.

Dual-Dynamic Chemistries-Based Fast-Reprocessing and High-Performance Covalent Adaptable Networks.

Covalent adaptable networks (CANs) possess multiple functions including reprocessing (or recyclability), self-healing, welding, shape shifting, 3D printing, etc., due to the network rearrangement from dynamic bonds, and favorable performance from their cross-linked feature, and they are supposed to be as sustainable alternatives to thermosets. However, the thermal and mechanical properties, and stability of CANs are often sacrificed for rapid network rearrangement. In this paper, fast-reprocessing CANs with high performance are facilely constructed by in situ polymerization and dynamic cross-linking of styrene (St), maleic anhydride (MA), and acetal diol (BHAD). The rigid and hydrophobic polymer backbone endow the materials with high glass transition temperatures, mechanical performance, and water resistance. Besides, carboxylic group-catalyzed dual dynamic ester and acetal-based networks exhibit faster stress relaxation and realize extrusion reprocessing. This work provides an ingenious and simple strategy of construction of CANs combining rapid network rearrangement and excellent comprehensive performance, which is beneficial for the application of CANs.

[Clinical and gastroscopic features of children with cyclic vomiting syndrome: an analysis of 63 cases]. / 儿童周期性呕吐综合征63例临床与胃镜分析.

OBJECTIVES: To study the clinical and gastroscopic features of children with cyclic vomiting syndrome. METHODS: A retrospective analysis was performed on the medical data of 63 children with cyclic vomiting syndrome who were hospitalized and followed up in Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University from August 2019 to March 2022. RESULTS: Among the 63 children, there were 30 boys and 33 girls, with a mean age of 6.11 years, a mean course of disease of 2.57 years, and a mean vomiting period of 4.04 days. The most common accompanying symptom was listlessness or somnolence (55/63, 87%), followed by anorexia (45/63, 71%), abdominal pain or abdominal discomfort (40/63, 63%), constipation (19/63, 30%), salivation (12/63, 19%), nausea (11/63, 17%), headache (11/63, 17%), fever (6/63, 10%), and rash (1/63, 2%). All 63 children underwent gastroscopy, among whom 3 had no marked abnormalities, 22 (35%) had chronic superficial gastritis or chronic non-atrophic gastritis alone, and 38 (60%) had other abnormal changes aside from chronic gastritis (16 children with reflux esophagitis, 12 with bile reflux gastritis, 13 with duodenitis, 10 with erosive gastritis, and 5 with gastric or duodenal ulcer). Among the 63 children, 42 underwent pathological examinations of gastric mucosa, among whom 5 had no marked abnormalities, 34 had mild chronic gastritis, 2 had moderate chronic gastritis, and 1 had severe chronic gastritis. Among the 63 children, 15 received 24-hour dynamic esophageal pH monitoring during the interictal period, among whom 9 children were found to have pathological acid reflux. CONCLUSIONS: In addition to recurrent vomiting, most children with cyclic vomiting syndrome also have the symptoms such as somnolence or listlessness, anorexia, and abdominal pain. The main manifestation on gastroscopy is chronic gastritis, and most children may also have reflux esophagitis, bile reflux gastritis, and erosive gastritis. Mild chronic gastritis is the main pathological change of gastric mucosa.

Comparison of anxiety and depressive symptoms of head and neck cancer patients in a closed-loop management system before and during the 2019 coronavirus pandemic: a comparative study.

BACKGROUND: The coronavirus disease of 2019 (COVID-19) poses an unprecedented challenge to health and the financial system, especially the healthcare of patients with cancer. However, the research on the negative effect of the pandemic on the anxiety and depressive symptoms of cancer patients in closed-loop is rarely reported at present. In view of the limitations of previous studies. In this study, we compared the anxiety and depressive symptoms of head and neck cancer patients in the closed-loop management system before and during the 2019 coronavirus pandemic. METHODS: In this comparative study, a total of 526 head and neck cancer patients (269 and 257 patients before and during the COVID-19 pandemic) were enrolled in the present study. The two groups of patients' median age (53 years, 52 years), female distribution (70.26%, 66.15%) and male distribution (29.74%, 33.85%) were analyzed before and after the COVID-19 epidemic. They received questionnaires using the standardized data forms of Self-Rating Anxiety Scale (SAS) and the Self-Rating Depression Scale (SDS) to collect the relevant data of patients for retrospective investigation. For data analysis, either the chi-squared test or Fisher's exact test was employed for categorical variables, and we described the time trend of psychological states before and after the outbreak with Cochran-Armitage trend (CAT) test. RESULTS: A total of 526 head and neck cancer patients were included in the final analysis; 26.85% and 50.19% of cases experienced anxiety and depression during the COVID-19 epidemic. In contrast, 18.22% and 33.46% of cases had experienced anxiety and depression before the pandemic. According to the statistical results, the prevalence of anxiety and depression in patients during the COVID-19 epidemic was higher compared to that of patients prior to the pandemic (P=0.018). More importantly, both anxiety and depression incidence trends increased significantly before and after the outbreak of COVID-19 (P=0.000). CONCLUSIONS: The present study demonstrates the significant impact of COVID-19 on the psychological states of cancer patients in the case of closed-loop management system, effectively indicating the need for appropriate changes in treatment decisions, enhanced psychotherapy, and interventions to reduce the incidence of anxiety, depression, and even suicide during this pandemic.

DDX24 regulates the chemosensitivity of hepatocellular carcinoma to sorafenib via mediating the expression of SNORA18.

Sorafenib (SFN) is a multi-kinase inhibitor drug for the treatment of advanced hepatocellular carcinoma (HCC), but its limited efficacy is a major obstacle to the clinical outcomes of patients with HCC. We aimed to explore a novel molecular mechanism underlying the chemosensitivity of HCC to SFN, and to identify a promising therapeutic target for HCC treatment. In this study, bioinformatic analysis revealed that DDX24 was associated with poor survival in HCC cases, and significantly related to the pathways modulating tumor development. DDX24 regulated HCC cell proliferation and migration potentials. Moreover, reduction of DDX24 promoted the sorafenib-mediated inhibition of HCC cell growth and migration, the elevation of sorafenib-induced HCC cell apoptosis. DDX24 overexpression suppressed the inhibitory effect of SFN on cell proliferation and migration and reduced the apoptosis induced by SFN. Further, DDX24, combined with SFN treatment, presented a synergistic enhancement of the sensitivity of SFN to the growth and migration of HCC cells via AKT/ERK and the epithelial-mesenchymal transition (EMT) pathways, and that it modulated apoptosis via the caspase/PARP pathway. Mechanistically, SNORA18 served as a target gene for DDX24, regulating the chemosensitivity of sorafenib-treated HCC cells. Furthermore, SNORA18 knockdown or overexpression could partially reverse the inhibition or elevation of cell viability, colony formation and migration induced by DDX24 in sorafenib-treated HCC cells, respectively. Collectively, our results suggest that DDX24 regulates the chemosensitivity of HCC to SFN by mediating the expression of SNORA18, which may act as an effective therapeutic target for improving SFN efficiency in HCC treatment.

Promotion of biomass pyrolytic saccharification and lignin depolymerization via nucleophilic reagents quenching of the carbonium ions.

The condensation of lignin under acidic conditions inhibited the subsequent value-added utilization of lignin, and the condensed lignin covered the biomass surface. Here, a method of benzenesulfonic acid pretreatment combined with nucleophilic reagents promoted pyrolytic saccharification and lignin hydrogenation was reported. The anhydrosugar content in the pyrolysis bio-oil increased from 66.91% to 69.00%, 72.88%, and 72.16% via adding methanol, propionaldehyde, 3-hydroxylic-2-naphthoic acid, respectively. The characterization of the biomass surface structure and the calculation of bond lengths indicated that carbonium ions prefer to bind with the added nucleophilic reagent rather than the lignin fragment. Furthermore, the quenching of the carbonium ions preserved the ß-O-4 bond, as demonstrated in 2D NMR. In the subsequent hydrogenation reaction, it was found that methanol facilitated the production of lignin monomer. The calculation also revealed that the quenching of the carbonium ions with methanol reduced the bond-breaking energy of the ß-O-4 bond.

Hydrothermal and photocatalytic synergistic pretreatment to improve the full utilization of corn stalk.

In this study, the hydrothermal and photocatalytic synergistic pretreatment for improving the full component utilization of corn stalk based on lignin first biorefining was employed to generate carbohydrates and obtain modified lignin. The results showed that the highest lignin removal ratio (40.70 %) and cellulose retention ratio (92.64 %) were obtained due to the smallest energy gap (6.05 eV) and the largest penetration distance (1.73 Å) between GVL and the lignin. And the yield of carbohydrates increased from 1.95 % to 58.17 % after hydrothermal pretreatment at 180 ℃. Furthermore, the modified lignin enhanced the flocculation effect, resulting in the increase of the removal of safranine-T by 6 times. In addition, the chemical and physical properties of modified lignin were studied and the mechanism of photocatalysis modification was explored. The research provides a new pretreatment method for the utilization of biomass and simultaneously achieves carbohydrate enrichment in bio-oil and purification of dye wastewater.

Crystallizable Aliphatic Chains Enhanced Covalent Adaptable Networks: Fast Reprocessing and Improved Performance.

Covalent adaptable networks (CANs) exhibit recyclability such as reprocessing, but it's a challenge to address the contradiction between reprocessing rate and performance. Here, pendent aliphatic chain anhydride monoesters are innovatively introduced into epoxy CANs based on transesterification, which efficiently accelerates the reprocessing without sacrificing thermal and mechanical properties. The transesterification rate is raised on account of the flexible aliphatic chain-promoted segment movement and dynamic transfer auto-catalysis. When the carbon number reflecting the length of the pendent chain is 12, the epoxy CAN exhibits the fastest stress relaxation or reprocessing. Computation via molecular dynamics simulation demonstrates that the increased segmental mobility from the pendent aliphatic chains contributes to enhanced reprocessability. Interestingly, the crystallization of the pendent aliphatic chains maintains or even improves the thermal and mechanical properties. Thus, introducing a flexible and crystallizable aliphatic side chain is an innovative and efficient approach to accelerate dynamic reactions and network arrangement while improving performance.

1α, 25-Dihydroxyvitamin D3 protects gastric mucosa epithelial cells against Helicobacter pylori-infected apoptosis through a vitamin D receptor-dependent c-Raf/MEK/ERK pathway.

CONTEXT: Due to the resistance of Helicobacter pylori to antibiotics, it is difficult to eradicate this pathogenic bacterium from the host. The role of 1α, 25-dihydroxyvitamin D3 (1,25-D3) in H. pylori-infected gastric mucosa epithelial cells remains unknown. OBJECTIVE: This study investigates the protective property of 1,25-D3 against H. pylori-infected apoptosis in gastric mucosa epithelial cells and its potential molecular mechanisms. MATERIALS AND METHODS: GES-1 cells were infected with H. pylori SS1 strain (MOI: 100) and treated with 1,25-D3 at 100, 200, and 300 nM for 24 h. Mice were orally gavaged with 108 CFUs of H. pylori and 25 µg/kg 1,25-D3 every other day for 1 month. CCK-8, LDH assay, TUNEL assay and western blot were used to determine the effect of 1,25-D3 on H. pylori-induced apoptosis. RESULTS: H. pylori infection decreased cell viability to 59.2%, while 100-300 nM 1,25-D3 increased cell viability to 62.2%, 78.4% and 87.1%, respectively. Compared with positive control (4.53-fold), 1,25-D3 reduced caspase-3 activity to 4.49-, 2.88- and 1.49-fold, reduced caspase-6 activity to 2.36-, 1.88- and 1.50-fold, reduced caspase-9 activity to 4.55-, 2.91- and 2.01-fold. 1,25-D3 alters Bcl-2 family, caspase protein expression and c-Raf/MEK/ERK phosphorylation levels in vivo and in vitro. Suppression of 1,25-D3 in apoptosis was reliant on binding to vitamin D receptor. The pharmacological inhibition of c-Raf/MEK/ERK phosphorylation blocked the anti-apoptotic effect of 1,25-D3. DISCUSSION AND CONCLUSION: 1,25-D3 protected gastric mucosa epithelial cells against H. pylori-infected apoptosis through a VDR-dependent c-Raf/MEK/ERK pathway.

Fast-Reprocessing, Postadjustable, Self-Healing Covalent Adaptable Networks with Schiff Base and Diels-Alder Adduct.

Covalent adaptable networks (CANs) are a new type of polymers, which possess excellent performance of thermosets and reprocessability of thermoplastics. Nevertheless, it is still a challenge to realize rapid reprocessing and postadjusting (adjust properties after preparation). Herein, for the first time, a method of combining Schiff base and Diels-Alder adduct in one network is developed to achieve rapid reprocessing and postadjusting. Through the dissociation of the Diels-Alder adduct at high temperatures, the cross-link densities of the networks are reduced, thereby accelerating the rearrangement of the networks and realizing the rapid reprocessing and self-healing. Moreover, the reconnecting degree of network after dissociation of Diels-Alder adduct can be easily controlled by annealing; as a result, the properties of the obtained CANs are postadjustable. This work provides a simple and promising approach of achieving excellent reprocessing and postadjusting for CANs via the synergism of an associative dynamic chemistry with a dissociative dynamic chemistry.

N,N-Dimethylformamide solvent assisted hydrothermal pretreatment of Chlorella for coproduction of sugar, nitrogenous compounds and carbon dots.

Microalgae are considered as a promising alternative to fossil fuels due to their ease of cultivation, short growth cycle and no occupation of cultivated land. In this study, N,N-Dimethylformamide (DMF) solvent was employed to assist hydrothermal pretreatment of Chlorella for coproduction of sugar, nitrogenous compounds and carbon dots (CDs). The effect of pretreatment conditions on the composition and pyrolysis bio-oil distribution of hydrothermal solid residues as well as CDs characteristic were investigated by varying the temperature (180-220 ℃) and reaction time (1-9 h). The results showed that pretreated residues had higher cellulose. And the yield of sugar and N-contained compounds reached 41.59% and 63.57% in the pyrolysis bio-oil of pretreated algae residues, respectively. Moreover, CDs obtained from hydrothermal solution fluoresced red under 365 nm excitation. The paper provides a new method for the complete utilization of microalgae.