Background::Radiation (IR)-induced DNA damage triggers cell cycle arrest and has a suppressive effect on the tumor microenvironment (TME). Wee1, a cell cycle regulator, can eliminate G2/M arrest by phosphorylating cyclin-dependent kinase 1 (CDK1). Meanwhile, programed death-1/programed death ligand-1 (PD-1/PDL-1) blockade is closely related to TME. This study aims to investigate the effects and mechanisms of Wee1 inhibitor AZD1775 and anti-PD-1 antibody (anti-PD-1 Ab) on radiosensitization of hepatoma.Methods::The anti-tumor activity of AZD1775 and IR was determined by 3-(4,5-dimethylthiazol-2-y1)-2,5-diphenyltetrazolium bromide (MTT) assay on human and mouse hepatoma cells HepG2, Hepa1-6, and H22. The anti-hepatoma mechanism of AZD1775 and IR revealed by flow cytometry and Western blot in vitro. A hepatoma subcutaneous xenograft mice model was constructed on Balb/c mice, which were divided into control group, IR group, AZD1775 group, IR + AZD1775 group, IR + anti-PD-1 Ab group, and the IR + AZD1775 + anti-PD-1 Ab group. Cytotoxic CD8 + T cells in TME were analyzed by flow cytometry. Results::Combining IR with AZD1775 synergistically reduced the viability of hepatoma cells in vitro. AZD1775 exhibited antitumor effects by decreasing CDK1 phosphorylation to reverse the IR-induced G2/M arrest and increasing IR-induced DNA damage. AZD1775 treatment also reduced the proportion of PD-1 +/CD8 + T cells in the spleen of hepatoma subcutaneous xenograft mice. Further studies revealed that AZD1775 and anti-PD-1 Ab could enhance the radiosensitivity of hepatoma by enhancing the levels of interferon γ (IFNγ) + or Ki67 + CD8 T cells and decreasing the levels of CD8 + Tregs cells in the tumor and spleen of the hepatoma mice model, indicating that the improvement of TME was manifested by increasing the cytotoxic factor IFNγ expression, enhancing CD8 + T cells proliferation, and weakening CD8 + T cells depletion. Conclusions::This work suggests that AZD1775 and anti-PD-1 Ab synergistically sensitize hepatoma to radiotherapy by enhancing IR-induced DNA damage and improving cytotoxic CD8 + T cells in TME.

Objective: To investigate GATA3 expression and the regulatory mechanism of m6A modification in the re- sponse of alveolar epithelial cells to radiation, and to provide a new therapeutic target for radiation-induced lung injury based on its pathogenesis. Methods: Human lung epithelial cell line (A549) and mouse lung epithelial cell line (MLE-12) were exposed to X-ray irradiation with a single dose of 10 Gy (dose rate 1 Gy/min) and 6 Gy (dose rate 0.75 Gy/min), respect- ively. The expression of VIRMA gene (RNA methylase) was inhibited by lipofection of A549 cells and MLE-12 cells with shRNA-VIRMA plasmid and siRNA-VIRMA interfering fragment, respectively. Quantification of m6A RNA methylation was performed by colorimetry. Changes in the expression of mRNAs of VIRMA, GATA3, and epithelial-mesenchymal transition (EMT) markers in irradiated A549 and MLE-12 cells were determined by qRT-PCR. Changes in the expression of VIRMA,  GATA3,  and  EMT  marker  proteins  in  irradiated  A549  and  MLE-12  cells  were  determined  by  Western  blot. Results: Radiation up-regulated the expression of methylase VIRMA in A549 and MLE-12 cells, which in turn enhanced the m6A of total RNA and the expression of GATA3 gene and protein, resulting in EMT. Furthermore, in A549 and MLE-12 cells, interference of the VIRMA gene significantly reduced the expression of GATA3 gene and protein and the expression of EMT-related molecules. Conclusion　 Radiation induces m6A modification in alveolar epithelial cells, which up-regu- lates the expression of GATA3 gene and induces EMT, thus playing an important role in the process of radiation-induced lung injury.

Objective: To propose reasonable suggestions to promote the standardization of clinical studies by reviewing the systematic reviews and meta-analyses of acupuncture-moxibustion treatment of essential hypertension (EH). Methods: Computer retrieval was conducted through Excerpta Medica Database (EMBASE), PubMed, China National Knowledge Infrastructure (CNKI), Chongqing VIP Database (CQVIP), China Biology Medicine Disc (CBM), and Wanfang Academic Journal Full-text Database (Wanfang) to collect systematic reviews and meta-analyses relevant to treating EH with acupuncture-moxibustion therapy. The time range was from the database's inception till July, 2020. The studies were screened based on the inclusion and exclusion criteria and then data-extracted. The study's quality and evidence ratings were performed by referring to the preferred reporting items for systematic review and meta-analysis (PRISMA), a measurement tool to assess systematic reviews 2 (AMSTAR 2), and the grading of recommendations, assessment, development, and evaluation (GRADE). Results: A total of 14 studies, 10 in Chinese and 4 in English, published between 2012 and 2019, were included, involving 70 outcome measures. The methodological quality was rated as critically low, the reporting was relatively complete or had certain flaws, and the evidence strength was rated as low or very low. Conclusion: Regarding the acupuncture-moxibustion treatment of EH, the methodological quality and outcome measure evidence of existing systematic reviews and meta-analyses are relatively low, and the reporting quality also expects further improvements.

The biological effects of low-dose radiation (LDR) are still a research hotspot in the field of radiobiology. As research deepens on LDR-induced biological effects and the mechanisms, growing evidence shows that LDR produces distinct biological effects from high-dose radiation, which questions the linear non-threshold model. This article reviews LDR-induced bystander effect, hormesis, adaptive response, and hyper-radiosensitivity, as well as the mechanisms, in order to provide a reference for the transformation of basic research on LDR-related biological effects to clinical application.

N 6-methyladenosine (m 6A) is the most abundant RNA base modification in mammals, especially in eukaryotic messenger RNA (mRNA). N 6-methyladenosine modification can regulate RNA splicing, translocation, stability and ultimately affect protein synthesis. m 6A modification is catalyzed by RNA writers, reduced by erasers and also be recognized by readers. Abnormal changes ofm 6A levels are closely related to tumor occurrence and development, including proliferation, growth, invasion and metastasis. In the process of tumor radiotherapy, m 6A modification affects the efficacy of radiotherapy by affecting DNA damage, tumor stem cell generation and tumor cell radiation sensitivity. This article reviews the role of m 6A-modified epigenetic regulation in malignant tumors and the research progress of its mechanism in tumor radiotherapy, in order to provide new ideas for the development of clinical tumor molecular targeted therapies and radiosensitizers.

L-2-aminobutyric acid (L-ABA) is an important chemical raw material and chiral pharmaceutical intermediate. The aim of this study was to develop an efficient method for L-ABA production from L-threonine using a trienzyme cascade route with Threonine deaminase (TD) from Escherichia. coli, Leucine dehydrogenase (LDH) from Bacillus thuringiensis and Formate dehydrogenase (FDH) from Candida boidinii. In order to simplify the production process, the activity ratio of TD, LDH and FDH was 1:1:0.2 after combining different activity ratios in the system in vitro. The above ratio was achieved in the recombinant strain E. coli 3FT+L. Moreover, the transformation conditions were optimized. Finally, we achieved L-ABA production of 68.5 g/L with a conversion rate of 99.0% for 12 h in a 30-L bioreactor by whole-cell catalyst. The environmentally safe and efficient process route represents a promising strategy for large-scale L-ABA production in the future.
Aminobutyrates ; chemical synthesis ; Bacillus thuringiensis ; enzymology ; Candida ; enzymology ; Escherichia coli ; enzymology ; Formate Dehydrogenases ; metabolism ; Leucine Dehydrogenase ; metabolism ; Threonine ; metabolism ; Threonine Dehydratase ; metabolism

Objective To investigate the effect of neuropilin-1 (NRP1) on radiation-induced epithelial-mesenchymal transition (EMT) by measuring the expressions of EMT-related transcription factors in the irradiated cells with different levels of NRP 1.Methods Human lung type Ⅱ epithelial cells (A549) were transfected with NRP1 over-expression lentiviral vector and NRP1 inhibition vector to construct two cell models of NRP1high-A549 and NRP1low-A549.A NRP1 knock-down cell model was also constructed by transferring siNRP1 into normal mouse lung epithelial MLE-12 cells that was validated at both protein and mRNA levels.A single dose of 10 Gy X-ray was delivered to these cell models,then total protein and RNA were extracted at 0,12,24 and 48 h after irradiation.The expressions of EMT-related transcription factors (Twist and ZEB1) and EMT markers (β3-catenin,N-cadherin,and Vimentin) in each cell model were detected by Western blot and qPCR.Results After 10 Gy irradiation,the expressions of NRP1 mRNA and protein were significantly increased in A549 and MLE-12 cells.The expressions of the mesenchymal markers (Vimentin and N-cadherin) and the transcription factors of ZEB1 and Twist were also significantly increased (A549:t=2.917,7.361,4.852,9.278,P＜0.01;MLE-12:t=9.652,31.357,30.985,17.266,P ＜0.01).The expressions of Vimentin and N-cadherin were significantly decreased in NRP1low-A549 (t =10.077,15.707,P ＜ 0.01) and siNRP1-MLE-12 cells (t =5.745,P ＜ 0.01),but the expression of epithelial marker (β3-catenin) was significantly increased in these cells.The expressions of N-Cadherin and Vimentin were significantly elevated (t =16.055,5.560,P ＜ 0.01),while β-catenin decreased significantly in NRP1high-A549 cells.After irradiation,the transcription factor of Twist in NRP1low-A549 group was significantly decreased (t=3.987,P＜0.01),while the transcription factors of ZEB1 and Twist in the NRP1high-A549 group increased in a time-dependent manner (t =11.289,2.903,P＜0.01).After irradiation,the transcription factor of ZEB1 decreased significantly in siNRP1-MLE-12 cells (t=13.449,P＜0.01),and the protein expressions of ZEB1 and Twist in siNRP1-MLE-12 cells were lower than those of control group in a time-dependent manner.Conclusions NRP1 promotes radiation-induced EMT in human and mouse epithelial cells through up-regulation of transcription factors of ZEB1 and Twist.

OBJECTIVE： To study the improvement effect and mechanism of methylated urolithin A on oleic acid-induced lipid accumulation in human liver cancer Huh-7 cells. METHODS： Oleic acid was adopted to induce lipid accumulation model cells. Huh-7 cells were divided into control group （culture medium）， model group （1 mmol/L oleic acid）， low-dose group （1 mmol/L oleic acid+10 μmol/L methylated urolithin A） and high-dose group （1 mmol/L oleic acid+20 μmol/L methylated urolithin A）. Oil red O staining was used to observe lipid accumulation in cells. Triglyceride（TG） enzyme assay was applied to determine the TG content in cells. PCR was employed to detect the mRNA expression of FASN， SREBP-1， PPAR-α and PPAR-γ in cells. Western blotting was used to determine the protein expression of FASN in cells. RESULTS： After induced by oleic acid， a large amount of lipid droplet accumulated around the cells； the intracellular lipid and TG content， mRNA expression levels of FASN， SREBP-1 and PPAR-γ， protein expression levels of FASN were increased significantly， while mRNA expression level of PPAR-α was decreased significantly （P＜0.01）. After intervened with methylated urolithin A， lipid droplet around the cells decreased significantly； the contents of lipid and TG in cells were decreased significantly， while the mRNA expression levels of FASN， SREBP-1 and PPARγ and protein expression level of FASN were decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS： Methylated urolithin A can improve oleic acid-induced lipid accumulation in Huh-7 cells， the mechanism of which may be associated with inhibiting fat synthesis， promoting lipid metabolism and down-regulating the expression of metabolism-related factors as FASN， SREBP-1 and PPAR-γ.

Objective To evaluate the effect of the bladder scanner upon maintaining the consistency of bladder filling in cervical cancer patients during the intensity-modulated radiotherapy.Methods The bladder volume change of 20 patients diagnosed with cervical cancer throughout radiotherapy were retrospectively analyzed to determine the timing of introducing the bladder scanner. Ten patients undergoing cervical cancer radiotherapy were selected to analyze the consistency between the bladder volume measured by bladder scanner and cone-beam CT (CBCT).The changes of bladder volume before and after the intervention of bladder scanner were statistically compared. Results In total,100 CBCT images of 20 patients were retrospectively analyzed. Nonparametric test demonstrated that the bladder volume significantly differed compared with the planning volume ( P< 0. 05). Bland-Altman plot illustrated high consistency between the bladder volume measured by the bladder scanner and CBCT images with a mean difference of-6. 66 cm3 (95％CI: - 53. 1-39. 83 cm3 ). Paired-t test showed there was statistical difference between the bladder volume before intervention and the planning bladder volume (P= 0. 000).The bladder volume after intervention did not significantly differ from the planning bladder volume (P= 0. 745). Conclusions The bladder volume significantly varies throughout the treatment process. Bladder scanner should be utilized prior to treatment. The bladder volume measured by the portable bladder scanner is consistent with the planning bladder volume.

Objective To explore the feasibility to set the breast board support plate angle to 0° for breast cancer patient in the intensity modulated radiation therapy. Methods A total of 60 patients with breast cancer who received the simultaneous integrated boost intensity-modulated radiation therapy ( SIB-IMRT) after breast-conserving surgery were enrolled form Oct 2015 to Feb 2017. They were randomly divided into three groups that the angle of the breast board support plate was 12°, 7° and 0° respectively. The ipsilateral lung V20 , V5 , Dmean , the heart V10 , V30 , Dmean and the collimator angle were compared among three groups. In addition, the distribution of the setup error was analyzed and the group system error and random error were calculated. Results There were no statistically significant differences in the ipsilateral lung V20, V5, Dmean and the heart V10, V30, Dmean among the three groups(P >0. 05). The sum of the collimator angle and the angle of the support plate was about 13. 4° for each group. Only the setup error of z (vertical) direction was statistically different (χ2 =78. 32, P<0. 001) and the median of the 0° group was closest to the value 0 and the quartile spacing was the smallest. The absolute error of y ( longitudinal) , z directions was statistically different (χ2 =7. 63, 22. 61,P<0. 05). In the z direction, the absolute error was reduced as the angle of the support plate decreased and 0°group was the smallest. In the y direction, the absolute error at 12° was the smallest, but had little difference with that at 0°. Among three groups, the smallest system error of the x(lateral) direction and y direction was at 0°, while that of the z direction was at 12°. Conclusions To set the breast board support plate 0° is feasible. The angle of the support plate can be replaced by the collimator angle, while the setup error of z direction could be significantly reduced.