XELOX (capecitabine plus oxaliplatin) plus bevacizumab (anti-VEGF-A antibody) with or without adoptive cell immunotherapy in the treatment of patients with previously untreated metastatic colorectal cancer: a multicenter, open-label, randomized, controlled, phase 3 trial.

Fluoropyrimidine-based combination chemotherapy plus targeted therapy is the standard initial treatment for unresectable metastatic colorectal cancer (mCRC), but the prognosis remains poor. This phase 3 trial (ClinicalTrials.gov: NCT03950154) assessed the efficacy and adverse events (AEs) of the combination of PD-1 blockade-activated DC-CIK (PD1-T) cells with XELOX plus bevacizumab as a first-line therapy in patients with mCRC. A total of 202 participants were enrolled and randomly assigned in a 1:1 ratio to receive either first-line XELOX plus bevacizumab (the control group, n = 102) or the same regimen plus autologous PD1-T cell immunotherapy (the immunotherapy group, n = 100) every 21 days for up to 6 cycles, followed by maintenance treatment with capecitabine and bevacizumab. The main endpoint of the trial was progression-free survival (PFS). The median follow-up was 19.5 months. Median PFS was 14.8 months (95% CI, 11.6-18.0) for the immunotherapy group compared with 9.9 months (8.0-11.8) for the control group (hazard ratio [HR], 0.60 [95% CI, 0.40-0.88]; p = 0.009). Median overall survival (OS) was not reached for the immunotherapy group and 25.6 months (95% CI, 18.3-32.8) for the control group (HR, 0.57 [95% CI, 0.33-0.98]; p = 0.043). Grade 3 or higher AEs occurred in 20.0% of patients in the immunotherapy group and 23.5% in the control groups, with no toxicity-associated deaths reported. The addition of PD1-T cells to first-line XELOX plus bevacizumab demonstrates significant clinical improvement of PFS and OS with well tolerability in patients with previously untreated mCRC.

Theoretical study on electrocatalytic carbon dioxide reduction over copper with copper-based layered double hydroxides.

The conversion of CO2 into valuable fuels and multi-carbon chemical substances by electrical energy is an effective strategy to solve environmental problems by using renewable energy sources. In this work, the density functional theory (DFT) method is used to reveal the electrocatalytic mechanism of CO2 reduction reaction (CO2RR) over the surface of CuAl-Cl-layered double hydroxides (LDHs) with Cu monoatoms (Cu@CuAl-Cl-LDH), Cu2 diatoms (Cu2@CuAl-Cl-LDH), orthotetrahedral Cu4 clusters (Td-Cu4@CuAl-Cl-LDH) and planar Cu4 clusters (Pl-Cu4@CuAl-Cl-LDH). The active sites, density of states, adsorption energy, charge density difference and free energy are calculated. The results show that CO2RR over all the above five catalysts can generate C2 products. Pl-Cu4@CuAl-Cl-LDH tends to generate C2H5OH, while the remaining four structures all tend to produce C2H4. Cuδ+ favors CO2RR, and Td-Cu4@CuAl-Cl-LDH with a larger positively charged area at the active site has the better electrocatalytic performance among the calculated systems with a maximum step height of 0.78 eV. The selectivity of the products C2H4 and C2H5OH depends on the dehydration of the intermediate *C2H2O to *C2H3O or *CCH; if the dehydration produces *CCH intermediate, the final product is C2H4, and if no dehydration occurs, C2H5OH is produced. This work provides theoretical information and guidance for further rational design of efficient CO2RR catalysts for energy saving and emission reduction.

A DFT study on methanol decomposition over single atom Pt/CeO2 catalysts: the effect of the position of Pt.

Pt/CeO2 catalysts exhibit excellent catalytic performance for the methanol dehydrogenation (MD) reaction. In this work, MD reactions on three systems of Pt1/CeO2(110)), Pt7/CeO2(110), and Pt1/Ce1-xO2(110) are investigated via density functional theory (DFT) calculations. The CH3OH adsorption, electronic structure of the catalyst, and mechanism of methanol decomposition (MD) are systematically calculated. The results reveal that the d-band center of the Pt atom moves away from the Fermi level in the order of Pt1/CeO2(110) < Pt7/CeO2(110) < Pt1/Ce1-xO2(110), and the order of the activity of the MD reaction is Pt1/CeO2(110) < Pt7/CeO2(110) < Pt1/Ce1-xO2(110). The results of the microkinetic dynamics simulation verify that only Pt1/Ce1-xO2(110) is conducive to the decomposition of methanol at low temperatures (373 K), and the products CO and H2 are easily dissociated from the catalyst surface. This work uncovers that both the small size and the Ce vacancy substituted sites of Pt favor the performance of the Pt/CeO2 catalyst, and provides theoretical guidance for the construction and design of efficient metal-support catalysts for the MD reaction.

Efficacy and Safety of Low-Dose versus High-Dose Postoperative Intrathecal Morphine in 62 Women Undergoing Elective Cesarean Section Delivery at Full Term.

BACKGROUND Adequate pain control is desired in women undergoing cesarean section. This study aimed to compare the efficacy and safety of low- and high-dose postoperative intrathecal morphine in 62 women undergoing elective cesarean section delivery at full term. MATERIAL AND METHODS We performed a prospective, randomized, controlled, multicenter clinical study from April to November 2022. Full-term, 22-38-year-old pregnant women who were singleton pregnancies, weighing 55-80 kg, scheduled for elective cesarean section, were enrolled. A total of 62 patients were randomly assigned into either the low-dose (60 µg morphine, N=32) or high-dose (100 µg morphine, N=30) group. Post-cesarean pain intensity was recorded at 4, 12, and 24 hours. Patients requiring additional rescue analgesics or with adverse effects were documented. RESULTS There were no differences in age, weight, height, gestational age, or operating time between the 2 groups (all P>0.05). The 2 groups also had no statistically significant differences in the resting and exercise pain intensities at 4, 12, and 24 hours after cesarean section (P>0.05). Most patients (53 patients) did not require additional analgesics, suggesting an overall successful analgesic rate of 85.5%. The low-dose group had a lower incidence of pruritus than the high-dose group (13% vs 40%, P=0.029). The 2 groups had no differences in the other adverse effects. CONCLUSIONS A single dose of intrathecal 60 µg morphine could provide adequate analgesia comparable with 100 µg morphine, with a lower incidence of pruritus, in Chinese women after cesarean delivery.

Characterization of the volatile profile and its estrogenic activity in Kadsura coccinea fruit.

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Kadsura coccinea (Lem.) A. C. Smith is an ethnomedicine used to treat abnormal menstruation, menopausal syndrome, and female infertility among the Dong Nationality in China. AIM OF THE STUDY: Our study aimed to identify the volatile oil profiles of the K. coccinea fruit and elucidate their estrogenic activity. MATERIALS AND METHODS: The peel volatile oil (PeO), pulp volatile oil (PuO), and seed volatile oil (SeO) of K. coccinea were extracted using hydrodistillation and qualitatively analyzed using gas chromatography-mass spectrometry (GC-MS). Estrogenic activity was evaluated in vitro using cell assay and in vivo using immature female rats. Serum 17ß-Estradiol (E2) and follicle-stimulating hormone (FSH) levels were detected using ELISA. RESULTS: In total, 46 PeO, 27 PuO, and 42 SeO components representing 89.96%, 90.19%, and 97% of the total composition, respectively, were identified. The compounds with the highest content in PeO, PuO, and SeO were ß-caryophyllene, γ-amorphene, and n-hexadecanoic acid, respectively. PeO induced proliferation of MCF-7 cells with an EC50 of 7.40 µg/mL. Subcutaneous administration of 10 mg/kg PeO significantly increased the weight of the uteri in immature female rats, with no effect on serum E2 and FSH levels. PeO acted as an agonist of ERα and ERß. PuO and SeO showed no estrogenic activity. CONCLUSION: The chemical compositions of PeO, PuO, and SeO of K. coccinea are different. PeO is the main effective fraction for estrogenic activities, providing a new source of phytoestrogen for the treatment of menopausal symptoms.

Emricasan for the treatment of liver cirrhosis: a meta-analysis of randomized controlled trials.

Introduction: The efficacy of emricasan for liver cirrhosis remains controversial. We conduct a systematic review and meta-analysis to explore the influence of emricasan versus placebo on the treatment of liver cirrhosis. Methods: We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through August 2021 and included randomized controlled trials (RCTs) assessing the efficacy of emricasan versus placebo for liver cirrhosis. This meta-analysis was performed using the random-effect model. Results: Four RCTs were included in the meta-analysis. Overall, compared with control group for liver cirrhosis, emricasan treatment had no substantial impact on MELD (SMD=-0.19; 95% CI=-0.44 to 0.06; P=0.14), INR (SMD=0.12; 95% CI=-0.13 to 0.37; P=0.36), total bilirubin (SMD=-0.27; 95% CI=-0.56 to 0.01; P=0.06), serum albumin (SMD=0; 95% CI=-0.25 to 0.25; P=1.00) or adverse events (OR=1.35; 95% CI=0.56 to 3.24; P=0.50). Conclusions: Emricasan treatment provided no benefit for the treatment of liver cirrhosis.

The role and value of surgeon-engineer interaction during preoperative planning of patient-specific instrumentation assisted total knee arthroplasty / 中华骨科杂志

Objective:To investigate the significance and importance of the interaction between surgeons and engineers during the preoperative planning phase of total knee arthroplasty (TKA) when utilizing patient-specific instrumentation (PSI).Methods:A retrospective review was conducted on 202 knees of PSI-assisted TKA performed on 178 patients between June 2018 and August 2022. The patients' mean age was 68.4±6.2 years, ranging from 53 to 86 years. Among the participants, there were 149 females and 29 males, 93 left knees and 109 right knees. The study involved 171 patients of osteoarthritis (193 knees) and 7 patients of rheumatoid arthritis (9 knees), with 194 knees presenting varus knees and 8 knees with valgus knees. The preoperative plan documents, from the initial engineer-designed plan to the final plan approved by the surgeon, were analyzed to assess the frequency, parameters, and reasons for adjustments made during the planning process.Results:The planning of the 202 PSI-assisted TKA was subjected to at least one round of surgeon-engineer interaction. Among the 202 TKA planning, 117 knees (57.9%) underwent modifications after discussion, with most plans (100 knees, 49.5%) being confirmed after one round of modification. Two rounds of modifications were performed on 10 knees (5.0%), and three rounds on 5 knees (2.5%). A maximum of four rounds of modifications were made on two knees (0.9%). Furthermore, in the case of the remaining 85 knees (42.1%), the surgeons promptly consented to the engineers' initial planning following the discussions. Specific adjustments were made in 106 knees (52.5%) regarding femoral parameters, 57 knees (28.2%) concerning tibial parameters, and 46 knees (22.8%) requiring adjustments to both femoral and tibial parameters. Notably, the most frequently adjusted parameter was the osteotomy thickness of the posterior femoral condyles, which was modified in 94 knees (80.3%). The reasons for adjusting femoral or tibial parameters were summarized, revealing the main factors as follows: 1) Discrepancy between the mediolateral and anteroposterior diameters of the femoral condyle; 2) Twisted deformity of the proximal tibia; 3) Severe flexion contracture deformity of the knee; 4) Collapse of the medial or lateral tibial plateau; 5) Evident anterior arch deformity of the femur.Conclusion:The interaction between surgeons and engineers plays a pivotal role in the preoperative phase of PSI-assisted TKA. Effective collaboration allows surgeons to accurately analyze the unique anatomical characteristics and pathological changes of each patient in a three-dimensional perspective, facilitating the formulation of individualized surgical plans.

Analysis of CT doses to paediatric patients in four children′s hospitals in Shanghai / 中华放射医学与防护杂志

Objective:To study the distribution of CT doses to paediatric patients in Shanghai by investigating the CT dose parameters availiable in Shanghai′s children′s hospticals, and to provide the basis for establishing the diagnostic reference level for the paediatic patients subjected to CT scanning in Shanghai.Methods:In 2021, a general survey was carried out of the CT doses to the head, chest and abdomen of the scanned paediatric patients in four children′s hospitals in the municipality. The scanned paediatic patients were divided into four age groups of 0-, 1-, 5- and 10-15 years old, each with 30 subjects. The basic information were collected on the subjects, CT scanning parameters, volume CT dose index (CTDI vol) and dose length product (DLP). SPSS 16.0 was used to carry out statistical analysis of the differences in CTDI vol and DLP between different age groups at the same site and between different hospitals for the same age group at the same site. Results:The 75 th percentile values of CTDI vol and DLP for 0-, 1-, 5- and 10-15 age groups were 25, 25, 28, 43 mGy and 402, 477, 504, 752 mGy·cm, respectively, for head scanning; 2.7, 2.2, 2.8, 5.4 mGy and 40, 48, 75 and 176 mGy·cm for chest; and 4.9, 4.4, 8.2, 12 mGy and 106, 131, 273, 471 mGy·cm for abdomen. There were significant differences in CTDI vol and DLP between different age groups at the same site and between different hospitals for the same age group at the same site (head, chest and abdomen CTDI vol:χ2=221.68, 167.27, 127.07, DLP: χ2=220.63, 261.46, 216.61; for four age groups, CTDI vol: head χ2=30.46, 38.39, 25.21, 73.04, chest χ2=30.46, 35.69, 58.92, and 48.03, abdomen χ2=66.58, 41.62, 48.93, and 67.38; DLP: head χ2=28.82, 72.49, 47.72, 52.34, chest χ2=28.82, 35.95, 50.66, 41.64, abdomen χ2=45.53, 26.02 39.34, 44.24, P <0.05 ). Conclusions:The 75 th percentile values of CTDI vol and DLP for head, chest and abdomen in 4 children′s hospitals in Shanghai are lower or close to the values given in the relevant national standards and the diagnostic reference levels in some European countries, with higher DLP values on some scanning sites. The CT scanning procedures for paediatric patients needs to be further optimized.

Diagnostic method and value of echocardiography for screening right patent ductus arteriosus in infants / 中华超声影像学杂志

Objective:To investigate the diagnostic method and value of echocardiography in screening right patent ductus arteriosus(PDA) of infants.Methods:This was a prospective study.Thirty-one infants with right PDA diagnosed by ultrasound and confirmed by prenatal ultrasonography, electronic computed tomography angiography, angiocardiography and/or surgery in Hebei Children′s Hospital from April 2014 to May 2022 were collected as research subjects, and the association of right ductus arteriosus with aortic arch anomalies and complex cardiac malformations were summarized. The diagnostic method and value of ultrasonic screening were summed up.Results:Of the 31 cases, 30 cases were correctly diagnosed by ultrasound and 1 case was misdiagnosed, who was a left aortic arch descending to the right, a crossover variation of the right and left pulmonary arteries, and a rightward displacement of the ductus arteriosus. Among these cases diagnosed correctly, 27 cases (including 24 cases with right aortic arch and 3 cases with left aortic arch) presented that ductus arteriosus was open and its ostium of pulmonary artery end was located in the proximal right pulmonary artery in views of parasternal short-axis view of great vessels at cardiac base with the combination of two dimensions and color Doppler flow imaging. Other 3 cases of right aortic arch were all single ventricle with transposition of the great artery. Due to the parallel relationship of the two great arteries, the standard parasternal short-axis view of great vessels could not be obtained, and the right ductus arteriosus was found in the high parasternal views.In all of the 27 cases with right aortic arch and right ductus arteriosus, high parasternal views showed that one end of the ductus arteriosus was connected to the right aortic arch isthmus and the other end was connected to the right pulmonary artery. In all of the 3 cases with left aortic arch and right ductus arteriosus, the high parasternal views showed that one end of the ductus arteriosus was connected to the right subclavian artery and the other end was connected to the right pulmonary artery. Among the 27 cases with right aortic arch, 16 cases were accompanied with mirror image branches, 9 cases of which had complex cardiac malformations; 10 cases were associated with aberrant left subclavian artery, 1 case of which had complex cardiac malformations; 1 case was with isolated left subclavian artery, and without complex cardiac malformations. All 3 cases of left aortic arch were accompanied with isolated right subclavian artery and none of them were associated with complex cardiac malformations. Clinical outcomes of 30 cases with right PDA: 14 cases underwent ductus arteriosus ligation due to thick ductus or other heart malformations. In other 16 cases, 4 cases were closed spontaneously, 9 cases had persistent small ductus arteriosus, and 3 cases were lost to follow-up.Conclusions:Right ductus arteriosus is mostly related to the right aortic arch, and those with mirror image branches are prone to complex cardiac malformations; cases of left aortic arch with right ductus arteriosus are tend to accompany isolated right subclavian artery. Ultrasound has an important application in the screening and diagnosis of right PDA.

Relationship between nursing student's learning engagement and teacher's support in a medical school in Shaanxi Province: mediating role of professional identity / 中华医学教育探索杂志

Objective:To analyze the mediating effect of professional identity between teacher's support and student's learning engagement in nursing students.Methods:A total of 409 nursing students were enrolled in this cross-sectional study. Their professional identity, teacher's support, learning engagement were evaluated by Professional Identification Scale (PIS), Nursing Students' Perceptions of Instructor Caring (NSPIC), and Utrecht Work Engagement Scale-Student (UWES-S). A mediating model was proposed and the impacts of professional identity on teacher's support and learning engagement were observed.Results:The average score of NSPIC was (4.60±0.67) points, that of PIS was (3.58±0.63) points, and that of UWES-S was (4.79±0.97) points. The scores of NSPIC and PIS were a highly positive correlation ( r=0.504, P<0.001). The scores of NSPIC was positively correlated with the scores of UWES-S ( r=0.362, P<0.001). The scores of PIS was positively correlated with the scores of UWES-S ( r=0.315, P<0.001). Multiple linear regression analysis showed that learning engagement of nursing students was associated with the total score of PIS and supportive learning atmosphere, which accounted for 16.6% of the total variability. Professional identity had a mediating effect between teacher's support and learning engagement, with statistic significance among all coefficients of each path ( P<0.05), and all the fitting indexes were good. Teachers support had direct effect (0.31) on learning engagement and indirect effect (0.11) on learning engagement through professional identity. Conclusion:Teacher's support can directly predict student's learning engagement and professional identity plays an mediating role between them.

Effect of H2O2 on Secondary Metabolism in Atractylodes chinensis and Its Mechanism / 中国实验方剂学杂志

ObjectiveTo investigate the effect of exogenous H2O2 on secondary metabolism in Atractylodes chinensis and its mechanism. MethodFresh rhizomes of A. chinensis were treated with 5.0， 1.0， 0.2， 0.04 mmol·L-1 H2O2 solution and clean water， and the relationships between the contents of reactive oxygen species， activities of antioxidant enzymes， activities of key enzymes of secondary metabolites， and contents of secondary metabolites in A. chinensis were compared. ResultUnder treatment with exogenous H2O2， the content of reactive oxygen species and malondialdehyde （MDA） in the fresh rhizomes of A. chinensis were significantly elevated on the 4th day， and returned to normal level on the 6th-8th day. The activities of superoxide dismutase （SOD）， catalase （CAT） and peroxidase （POD） were all increased first and then decreased， and reached the peak on the 4th， 4th-6th and 2th-4th day， respectively. The activities of 3-hydroxy-3-methyl glutaryl coenzyme A reductase （HMGR） and acetyl CoA carboxylase （ACC）， key enzymes of the secondary metabolites， were remarkably enhanced， and under treatments with different concentrations of H2O2， the activities of key synthetic enzymes of the secondary metabolites in 0.2 mmol·L-1 H2O2 group were increased most， with the highest biosynthesis of secondary metabolites. The contents of atractylodin， β-eudesmol， atractylone， atractylenolide Ⅱ， and atractylenolide Ⅲ on the 6th day of 0.2 mmol·L-1 H2O2 treatment were 89.5%， 108.7%， 308.8%， 64.7% and 9.3%， respectively higher than those in the control. ConclusionThe antioxidant enzymes and secondary metabolites in A. chinensis synergistically maintain the balance of reactive oxygen species， and exogenous H2O2 can improve the medicinal quality of A. chinensis remarkably.

Analysis of quality control and protection level test results of medical electron linear accelerators in Shanghai, China / 中国辐射卫生

@#<b>Objective</b> To investigate the quality control and protection level of medical electron linear accelerators in Shanghai, China. <b>Methods</b> The startified random sampling method was used to cover tertiary, secondary and ungraded hospitals, and a total of 30 medical electron linear accelerators in 15 hospitals were tested for quality control and protection level according to relevant standards. <b>Results</b> Five medical electron linear accelerators failed the quality control test, with an overall inspection pass rate of 83.3% and a re-inspection pass rate of 100%. The pass rate of flatness of square X-ray irradiation field (5 cm × 5 cm)-(30 cm × 30 cm) was 83.3%, the pass rate of symmetry of square X-ray irradiation field was 96.7%, and other indices were qualified. All medical electron linear accelerator rooms passed the protection test. <b>Conclusion</b> The protection of medical electron linear accelerator rooms in Shanghai meets the requirements of national standards, and some indices do not meet the requirements of national standards in the preliminary inspection. The quality control of medical electron linear accelerators should be further strengthened to ensure the treatment effect of patients.

Short-Term Changes of Graft Viscosity after Anterior Cruciate Ligament Reconstruction / 医用生物力学

Objective To study the short-term variation patterns of graft viscosity after anterior cruciate ligament reconstruction (ACLR) surgery. Methods Six male New Zealand rabbits were selected. The ACLR animal model of unilateral knee was made with Achilles tendon as the graft. The experimental rabbits were euthanized 15 days after ACLR surgery, with removal of the graft, healthy anterior cruciate ligament (ACL) and Achilles tendon. The cross-sectional area and viscosity coefficient of the graft were measured, and the creep experiments were carried out under equilibrium conditions of 0.1 MPa and 1 MPa, respectively. The viscosity coefficent was calculated. Variation patterns of graft viscosity were summarize. The grafts were compared with healthy ACL. Results The cross-sectional area of the graft increased slowly within 15 days after ACLR surgery. The viscosity of ACL and graft changed nonlinearly. The viscosity coefficient was quite different under different stresses. The viscosity coefficient of the graft decreased with the time after ACLR surgery, which was more obviously under the condition of low stress. Conclusions The results are helpful to guide the implementation of early postoperative rehabilitation plan after ACLR surgery .

Effects of Cyclic Strain on Neural Differentiation of Rat Bone Marrow-Derived Mesenchymal Stem Cells / 医用生物力学

Objective To study the mechanical effects of cyclic strain on neural differentiation of rat bone marrow mesenchymal stem cells (rBMSCs). Methods The rBMSCs were subjected to cyclic strain for 24 hours andthen cultured for 5 days. The expression of neural markers and the phosphorylation of relative signaling pathway proteins were evaluated. The stress distribution on cell surface was analyzed by finite element method. The differentially expressed genes induced by strain were identified by RNA sequencing analysis. Results The 0. 5 Hz strain with 5% magnitude could significantly induce higher expression of neural markers and elevated phosphorylation level of extracellular-signal-regulated kinase (ERK), protein kinase B (AKT) and mammalian target of rapamycin ( mTOR). KEGG pathway analysis showed that the focal adhesion and ECM-receptor interaction were significantly enriched under cyclic strain. Conclusions Cyclic strain could change the interaction of cells with the extracellular matrix ( ECM) and enhance the AKT/ mTOR and ERK pathway, finally promote rBMSC neural differentiation. Knowledge about the impact of mechanical stimulation on BMSC neural differentiation is expected to improve the efficiency of stem cell differentiation, shed light on device design for tissue engineering, and promote clinical application of mesenchymal stem cells in neural issue repair and regeneration.

LOX-1 Regulation in Anti-atherosclerosis of Active Compounds of Herbal Medicine: Current Knowledge and the New Insight / 中国结合医学杂志

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) have recently been identified to be closely related to the occurrence and development of atherosclerosis (AS). A growing body of evidence has suggested Chinese medicine takes unique advantages in preventing and treating AS. In this review, the related research progress of AS and LOX-1 has been summarized. And the anti-AS effects of 10 active components of herbal medicine through LOX-1 regulation have been further reviewed. As a potential biomarker and target for intervention in AS, LOX-1 targeted therapy might provide a promising and novel approach to atherosclerotic prevention and treatment.

Biological Mechanism of Drought Improving Quality of Rhizoma Atractylodis Chinensis / 中国实验方剂学杂志

ObjectiveTo explore the biological mechanism of drought improving the quality of Rhizoma Atractylodis Chinensis and establish a new method for the production of high-quality medicinal materials. MethodThe fresh roots of Atractylodes chinensis were soaked in 0 （control）， 5%， 10%， and 20% PEG-6000 solutions. The changes in reactive oxygen species （ROS） level， antioxidant enzyme activity， activities of key enzymes in primary metabolism and secondary metabolism， and content of secondary metabolites were compared. ResultCompared with the control group， the treatment with 20% PEG for 2 days elevated the levels of superoxide anion radicals （O2-·）， hydrogen peroxide （H2O2）， and malondialdehyde （MDA） by 172.5%， 56.9%， and 14.7%， respectively. The treatment did not change the activity of superoxide dismutase （SOD）， reduced the peroxidase （POD） activity， and increased the catalase （CAT） activity by 10.8%. It increased the activities of 3-hydroxy-3-methylglutaryl-CoA reductase （HMGR）， phosphoenolpyruvate carboxylase （PEPC）， and acetyl-CoA carboxylase （ACC） by 49.9%， 12.1%， and 19.0%， respectively. Furthermore， the content of atractylodin， β-eudesmol， atractylone， and atractylenolide Ⅱ was increased by 51.0%， 36.9%， 47.1%， and 91.5%， respectively. The simulated drought stress can cause the burst of ROS in the fresh roots of A. chinensis， induce the physiological state of plants under drought， change the antioxidant system， and promote the massive synthesis of secondary metabolites in a short time. ConclusionPEG-6000-simulated drought stress can greatly improve the quality of A. chinensis in cultivation.

Effectiveness of personal dose monitoring intercomparison results in a laboratory in Shanghai / 环境与职业医学

Background Individual monitoring of occupational external exposure is an essential part of the occupational health management of radiation workers, and is an important basis for the evaluation of individual absorbed dose and the diagnosis of occupational radiation diseases. Continuous participation of monitoring service providers in intercomparison is a fundamental quality assurance for routine monitoring, which can identify problems and improve them in time. Objective Taking the Laboratory of Radiation Protection in Shanghai Institute of Preventive Medicine as an example, to evaluate the performance of an individual occupational external dose monitoring system in the laboratory, identify influencing factors of the monitoring results, and provide a basis for improving the quality of daily monitoring by analyzing the process and results of a national intercomparison of individual dose monitoring. Methods According to the Testing criteria of personnel dosimetry performance for external exposure (GBZ 207-2016), and the relevant requirements of Class II (photon) inspection, a total of 20 groups of blind sample dosimeters were measured for four consecutive years from 2018 to 2021. The radiation energy source of each group was identified, and related personal dose equivalent Hp(10), the uncertainty of measurement results, and the deviation between the reported value and the reference value were calculated. The national intercomparison process and results of individual dose monitoring were also analyzed. Results The energy sources of the blind samples in the tested laboratory for four years were N100 or Cs-137. The reported dose values of the blind samples were 0.57-4.61 mSv, the combined uncertainties were 0.043-0.365 mSv, the expanded uncertainties (k=2) were 0.09-0.73 mSv, and the relative expanded uncertainties (k=2) were 13.8%-16.4%. The single-group performance ∣Pi∣ of 20 sets of blind samples in the four years was ≤0.10, the yearly comprehensive performance of 5 sets of blind samples was ≤0.10, and the yearly Q score of the test report was >15 points. The laboratory achieved excellent results in the national intercomparison of individual dose monitoring in four consecutive years, except the Q value not reaching full score. Conclusion The laboratory exhibits standardized data processing of individual dose monitoring, generates accurate and reliable results, and meets the requirements of relevant national standards; but it should continue to participate in the national intercomparison of individual dose monitoring, strengthen the angular response research of energy identified dosimeter, improve the monitoring ability of low-dose X-rays, analyze the key points of reducing the uncertainty of measurement results, and continuously improve the monitoring ability.

Enhanced recombinant carbonic anhydrase in T7RNAP-equipped Escherichia coli W3110 for carbon capture storage and utilization (CCSU).

Sulfurihydrogenibium yellowstonense carbonic anhydrase (SyCA) is a well-known thermophilic CA for carbon mineralization. To broaden the applications of SyCA, the activity of SyCA was improved through stepwise engineering and in different cultural conditions, as well as extended to co-expression with other enzymes. The engineered W3110 strains with 4 different T7 RNA polymerase levels were employed for SyCA production. As a result, the best strain WT7L cultured in modified M9 medium with temperature shifted from 37 to 30 °C after induction increased SyCA activity to 9122 U/mL. The SyCA whole-cell biocatalyst was successfully applied for carbon capture and storage (CCS) of CaCO3. Furthermore, SyCA was applied for low-carbon footprint synthesis of 5-aminolevulinic acid (5-ALA) and cadaverine (DAP) by coupling with ALA synthetase (ALAS) and lysine decarboxylase (CadA), suppressing CO2 release to -6.1 g-CO2/g-ALA and -2.53 g-CO2/g-DAP, respectively. Harnessing a highly active SyCA offers a complete strategy for CCSU in a green process.

Pancreatic-Like Cells Derived From Mouse Embryonic Stem Cells Are Regulated by Pdx1 Involving the Notch Pathway.

OBJECTIVES: Embryonic stem cells (ESCs)-derived pancreatic precursor cells have great potential for pancreas repair. Expression of pancreatic duodenal homeobox 1 (Pdx1) in definitive endoderm (DE) cells is the premise that DE cells differentiate into pancreatic cells. To achieve the required number of Pdx1-expressing DE cells for cell transplantation therapy, a valid model must be established. Using this model, researchers investigated how Pdx1 regulates ESC differentiation into pancreatic cells. METHODS: Tet-On inducible lentiviral vector encoding Pdx1 or mock vector was transduced into mouse ESC (ES-E14TG2a). The mouse ESCs were divided into 3 groups: control (ESC), mock vector (Pdx1 - -ESC), and vector encoding Pdx1 (Pdx1 + -ESC). All groups were separately cocultured with the DE cells sorted by immune beads containing CXCR-4 + (C-X-C chemokine receptor type-4) antibody. Doxycycline induced the expression of Pdx1 on the Pdx1 + -ESC cells. The markers of cell differentiation and Notch pathway were examined. RESULTS: Significantly increased expression levels of Ptf1a, CK19, and amylase on day (d) 3 and d7, Neuro-D1 on d10 and d14, Pax6 and insulin on d14, as well as Notch1, Notch2, Hes1, and Hes5 on d3 and thereafter declined on d14 were observed in Pdx1 + -ESC group. CONCLUSIONS: Pdx1 + -ESC could differentiate into pancreatic-like cells with involvement of the Notch pathway.