Physiological regulation of salicylic acid on Helianthus tubeuosus upon copper stress and root FTIR analysis / 生物工程学报

Phytoremediation plays an important role in the treatment of heavy metal pollution in soil. In order to elucidate the mechanism of salicylic acid (SA) on copper absorption, seedlings from Xuzhou (with strong Cu-tolerance) and Weifang Helianthus tuberosus cultivars (with weak Cu-tolerance) were selected for pot culture experiments. 1 mmol/L SA was sprayed upon 300 mg/kg soil copper stress, and the photosynthesis, leaf antioxidant system, several essential mineral nutrients and the changes of root upon copper stress were analyzed to explore the mechanism of copper resistance. The results showed that Pn, Tr, Gs and Ci upon copper stress decreased significantly compared to the control group. Meanwhile, chlorophyll a, chlorophyll b and carotenoid decreased with significant increase in initial fluorescence (F0), maximum photochemical quantum yield of PSⅡ (Fv/Fm), electron transfer rate (ETR) and photochemical quenching coefficient (qP) content all decreased. The ascorbic acid (AsA) content was decreased, the glutathione (GSH) value was increased, the superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in the leaves were decreased, and the peroxidase (POD) activity was significantly increased. SA increased the Cu content in the ground and root system, and weakened the nutrient uptake capacity of K, Ca, Mg, and Zn in the root stem and leaves. Spray of exogenous SA can maintain the opening of leaf stomata, improve the adverse effect of copper on photosynthetic pigment and PSⅡ reaction center. Mediating the SOD and APX activity started the AsA-GSH cycle process, effectively regulated the antioxidant enzyme system in chrysanthemum taro, significantly reduced the copper content of all parts of the plant, and improved the ion exchange capacity in the body. External SA increased the content of the negative electric group on the root by changing the proportion of components in the root, promoted the absorption of mineral nutrient elements and the accumulation of osmoregulatory substances, strengthened the fixation effect of the root on metal copper, and avoided its massive accumulation in the H. tuberosus body, so as to alleviate the inhibitory effect of copper on plant growth. The study revealed the physiological regulation of SA upon copper stress, and provided a theoretical basis for planting H. tuberosus to repair soil copper pollution.

Development of professional grief scale for medical postgraduate students and its reliability and validity / 中华行为医学与脑科学杂志

Objective:To develop a professional grief scale for medical postgraduate students(PGS-MPS) and test its reliability and validity.Methods:Based on the integrated model of professional grief, the initial item pool was formed after literature analysis, semi-structured interviews, group discussion, and 5 experts were invited to assess the relevance of the items and provided revision suggestion.A total of 506 valid questionnaires were collected.SPSS 25.0 and AMOS 26.0 were used to test its reliability and validity.Results:The PGS-MPS included 41 items, including the professional grief reaction subscale and disenfranchised grief subscale.The professional grief reaction subscale included emotional reaction (14 items), physiological and cognitive reaction (20 items), and the cumulative variance contribution rate of the two factors model was 52.908%.Disenfranchised grief subscale included 7 items, with a single dimension and a variance contribution rate of 51.730%.Confirmatory factor analysis indicated the model fitting well.The Cronbach’s α coefficients for the professional grief reaction subscale and disenfranchised grief subscale were 0.947 and 0.850, respectively.Conclusion:The PGS-MPS has good reliability and validity and can be used to evaluate professional grief of medical postgraduate students.

Effects of glycogen synthase kinase 3 inhibitors on the proliferation and apoptosis of chronic myelogenous leukemia K562 cells induced by imatinib / 白血病·淋巴瘤

Objective:To explore the effects of glycogen synthase kinase 3 (GSK3) inhibitors on the proliferation and apoptosis of chronic myelogenous leukemia (CML) K562 cells induced by imatinib.Methods:K562 cells were treated with 1 μmol/L imatinib combined with GSK3 inhibitor lithium chloride with different concentrations of 1.0, 2.0, 4.0 mmol/L, SB216763 with different concentrations of 0.5, 1.0, 5.0 μmol/L andTWS119 with different concentrations of 0.5, 1.0, 5.0 μmol/L, and then 1μmol/L imatinib was used as the control group. The proliferation activity of K562 cells was determined by using CCK8 assay. Flow cytometry was used to detect the cell apoptosis. The level changes of Wnt-β-catenin pathway related-protein were analyzed by using Western blot.Results:There were statistically significant differences of K562 cell survival rate between 1 μmol/L imatinib combined with different concentrations of SB216763, lithium chloride, TWS1193 groups and the control groups (all P < 0.01). The cell survival rate of 1 μmol/L imatinib + 1.0 μmol/L SB216763 group, 1 μmol/L imatinib + 5.0 μmol/L SB216763 group was (73.6±3.0)%, (77.0±3.6)%, which was higher than that of the control group [(68.0±2.8)%], and the difference was statistically significant (both P < 0.05). The cell survival rate of 1 μmol/L imatinib + 0.5 μmol/L SB216763 group was (70.0±2.2)%, and there was no statistical difference between 1 μmol/L imatinib + 0.5 μmol/L SB216763 group and the control group ( P > 0.05). The cell survival rate of 1 μmol/L imatinib + 2.0 mmol/L lithium chloride group and 1μmol/L imatinib + 4.0 mmol/L lithium chloride group was (75.5±3.6)%, (83.4±3.9)%, which was higher than that of the control group [(69.5±2.1)%], and the difference was statistically significant (both P < 0.05); there was no statistical difference in the cell survival rate of 1 μmol/L imatinib + 1.0 mmol/L lithium chloride group [(72.3±6.0)%] and the control group ( P > 0.05). The cell survival rate of 1 μmol/L imatinib combined with 0.5, 1.0, 5.0 μmol/L TWS119 was (70.0±1.1)%, (72.1±0.8)%, (73.8±0.7)%, respectively, which was higher than that of the control group [(67.9±7.5)%] (all P < 0.01). The cell apoptosis rate of 1 μmol/L imatinib + 5.0 μmol/L SB216763, 1 μmol/L imatinib + 4.0 mmol/L lithium chloride, 1 μmol/L imatinib + 5.0 μmol/L TWS119 was (18.16±3.59)%, (20.11±2.98)%, (16.27±2.36)%, respectively, which was lower than that of the control group [(28.26±2.20)%], and the difference was statistically significant (all P < 0.05). Compared with the imatinib group alone, there was no statistical difference in the protein expression levels of t-GSK3β, t-GSK3α of K562 cells treated with imatinib combined with GSK3 inhibitors, while the protein expression levels of p-GSK3β, p-GSK3α, β-catenin were increased. Conclusion:GSK3 inhibitors could reduce the effect of imatinib on the proliferation and apoptosis of CML K562 cells through regulating the related-protein level of Wnt-β-catenin pathway.

Tannic acid-Aluminum (Ⅲ) coordination-enabled microcapsules for pH-responsive protein vaccine delivery / 国际生物医学工程杂志

Objective To establish a simple and gentle antigen loading method to prepare pH-responsive and biodegradable microcapsules for efficient antigen delivery.Methods Co-precipitation method was used to embed chicken egg albumin (OVA) in CaCO3 particles.Then,TA and Al (Ⅲ) were coated on the surface of CaCO3 particles template by metal-organic coordination bonds.The CaCO3 template was removed from disodium edetate to obtain TA-Al(Ⅲ) microcapsules carrying OVA,i.e.the OVA@TA-Al(Ⅲ) microcapsules.The microcapsules were characterized by field emission scanning electron microscopy,transmission electron microscopy,X-ray energy spectrometry and atomic force microscopy.The distribution of OVA in the microcapsules was observed by laser scanning confocal microscopy.The cumulative release rate of OVA in the microcapsules at different pH phosphate buffers was also investigated.The cytotoxicity of the microcapsules on immortalized mouse dendritic cells DC2.4 was observed by thiazolyl blue assay.The phagocytosis of the microcapsules by DC2.4 cells was observed by laser scanning confocal microscopy.Results The results of field emission scanning electron microscope and transmission electron microscopy showed that the OVA@TA-Al(Ⅲ) microcapsules have a intact structure and a hollow and collapsed appearance with a diameter of about 4 μm.X-ray energy spectrum showed that there are five kinds of elements,i.e.C,O,Al,Si and Na,in the microcapsules,among which C,Al and some O elements belong to the composition of the microcapsules.Atomic force microscopy showed that the microcapsules have an ultra-thin wall,and the walls of the microcapsules are uniform in thickness (about 16 nm).Laser scanning confocal microscopy showed that OVAs were evenly distributed in the CaCO3 particles.Moreover,the pH sensitivity of the coordination bond makes the OVA@TA-Al(Ⅲ) microcapsules have pH responsiveness.In addition,the microcapsules also have good biocompatibility,and the DC2.4 cells also have good phagocytic ability to the microcapsules.Conclusion A simple and gentle antigen-encapsuling method was developed to achieve effective antigen payload and pH responsive delivery.The prepared microcapsules are expected to be used as a novel antigen delivery vector for clinical research.

Common Walking Fault of Multileaf Collimator in Linear Accelerator / 中国医疗器械杂志

This paper introduces the failure phenomenon, failure analysis, maintenance process and method of SIEMENS PRIMUS linear accelerator.

Screening of early prediction ultrasonic index for prognosis of severe hepatitis and its value evaluation / 中华超声影像学杂志

Objective To select early prediction indexes related to the prognosis of severe hepatitis in ultrasonography,and evaluate its clinical value.Methods Clinical data of 269 cases of severe hepatitis patients was analyzed retrospectively.Cox proportional hazards regression model was adopted to analyze 13 possible prediction ultrasonic parameters for severe hepatitis,including thickness of the right hepatic lobe,portal vein (PV) diameter,volume of ascites,etc.After selected from these parameters,the clinical value of early prediction factor was evaluated with ROC curve.Results Multivariate analysis showed that thickness of the right hepatic lobe,portal vein (PV) diameter,opening of paraumbilical vein and bile viscosity were related to the death of severe hepatitis patients (P ＜ 0.05).The thickness of the right hepatic lobe contributed most (Wald =40.479),its sensitivity and specificity for prediction were 93.4％,82.8％ respectively(P ＜ 0.01).Conclusions Thickness of the right hepatic lobe,PV diameter,opening paraumbilical vein and bile viscosity are early prediction factors for severe hepatitis,need to be monitored in treatment,especially for thickness of the right hepatic lobe.

(TTTTA)n polymorphism analysis in the 5' control region of apollipoprotein(a) gene in patients with coronary heart disease and the association with serum lipid level / 中国病理生理杂志

AIM: To investigate the pentanucleotide repeat(PNR) polymorphism of apolipoprotein(a) in patients with coronary heart disease(CHD) in Hubei area, and evaluate the association of polymorphism of apo(a) PNR with the level of serum lipid. METHODS: Objects examined were composed of two groups: 88 patients with CHD and 153 healthy controls. Lp(a), TC,TG, HDL-C, LDL-C, ApoAⅠand ApoB of two groups were tested. Meanwhile,the PNR in the 5' control region of the Apo(a) was detected by using polymerase chain reaction (PCR) and high voltage polyacrylamid gels electropherosis. RESULTS: The serum Lp(a), TC, TG and LDL-C levels were remarkably higher in the CHD than that in control( P