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ObjectiveTo investigate the effects of the inoculation of potassium-solubilizing bacteria on the rhizosphere soil microenvironment of Paris polyphylla var. yunnanensis. MethodThe effects of different potassium-solubilizing bacteria on the physical and chemical properties， microbial community structure， and soil enzyme activity in the rhizosphere soil of P. polyphylla var. yunnanensis were investigated by pot planting at room temperature. The correlation of various indexes was analyzed. ResultThe inoculation with different potassium-solubilizing bacteria could significantly affect the physical and chemical properties of rhizosphere soil of P. polyphylla var. yunnanensis. The mass fractions of available nitrogen， available phosphorus， and available potassium were 24.5-90.5 mg·kg-1， 2.53-25.9 mg·kg-1， and 132-312 mg·kg-1， respectively， and the soil pH was 7.08-7.75， which were in line with the optimal ranges of P. polyphylla var. yunnanensis planting. The inoculation of different potassium-solubilizing bacteria could affect the number of bacteria， actinomycetes， and fungi in rhizosphere soil to varying degrees. The transformation of soil from "fungal type" to "bacterial type" marks the improvement of soil fertility. It also affected the enzyme activity of rhizosphere soil， and the activities of neutral phosphatase， protease， and polyphenol oxidase showed an increasing trend. The correlation analysis showed that the number of bacteria was negatively correlated with the number of fungi （r=-0.856， P<0.01）， positively correlated with the number of actinomycetes， the content of available nitrogen and available potassium， and negatively correlated with soil pH. ConclusionThe inoculation of potassium-solubilizing bacteria can effectively improve the content of available potassium， available nitrogen， available phosphorus， and other nutrients in the rhizosphere soil of P. polyphylla var. yunnanensis， improve soil fertility， alleviate the continuous cropping obstacles of P. polyphylla var. yunnanensis， and lay a theoretical foundation for the green and sustainable development of P. polyphylla var. yunnanensis.
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ObjectiveTo investigate the effects of inoculation of potassium-solubilizing bacteria on the physiological characteristics of Paris polyphylla var. yunnanensis. MethodThe effects of different potassium-solubilizing bacteria on leaf area，photosynthetic pigment content， and active component indexes of P. polyphylla var. yunnanensis were investigated by pot planting at room temperature. ResultThe results showed that the inoculation of potassium-solubilizing bacteria could increase the leaf area of P. polyphylla var. yunnanensis. The largest average leaf area was observed in the S3 group，reaching 10.497 cm2，with a maximum increase of 11.0% compared with that of the CK group. The inoculation of potassium-solubilizing bacteria could increase the content of photosynthetic pigments in leaves. Among them，the increase in chlorophyll a content was significant （P<0.05），which was 80.6% higher than that of the CK group. The chlorophyll a/b values in all treatment groups were higher than that of the CK group. The activities of superoxide dismutase（SOD），catalase（CAT） and peroxidase（POD） in the leaves of P. polyphylla var. yunnanensis increased by 88.4%，33.8%， and 30.6%，respectively， as compared with that in the CK group. The inoculation of potassium-solubilizing bacteria could promote the accumulation of osmoregulation substances such as soluble sugar and soluble protein in leaf cells of P. polyphylla var. yunnanensis，with a maximum increase of 55.3% and 70.5% respectively compared with that of the CK group. Meanwhile，it also reduced the content of malondialdehyde（MDA），with a maximum decrease of 34.1% compared with that of the CK group. The results of correlation analysis showed that there were some correlations between different chemical components in P. polyphylla var. yunnanensis leaves. ConclusionThe inoculation of potassium-solubilizing bacteria can effectively promote the growth and development of P. polyphylla var. yunnanensis and improve its survival ability in adversity. It is of practical scientific significance and potential application value for improving the survival rate of P. polyphylla var. yunnanensis by artificial planting.
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Objective:To investigate and analyze the effect of ubiquitin-editing protein A20 on monocytes activity in patients with ventilator-associated pneumonia (VAP).Methods:Twenty-four VAP patients (VAP group) and twelve healthy controls (control group) were included from the First Affiliated Hospital of Zhengzhou University between February 2019 and September 2019. Peripheral blood mononuclear cells (PBMCs) and bronchial alveolar lavage fluid (BALF) (both infection site and non-infection site) were collected from VAP patients, while PBMCs were collected from healthy controls. A20 level in CD14 + monocytes were measured. CD14 + monocytes and CD4 + T cells were purified from VAP patients. CD14 + monocytes were transfected by A20 siRNA. Transfected CD14 + monocytes were directly/indirectly co-cultured with autologous CD4 + T cells. The secretion of interferon-γ (IFN-γ) and interleukin-17 (IL-17) by CD4 + T cells was investigated. Transfected CD14 + monocytes were directly/indirectly co-cultured with NCI-H889 cells. Cytotoxicity, and cytokines/granzyme B level, and tumor necrosis factor-related apoptosis inducing ligand (TRAIL)/Fas ligand (FasL) level was assessed. Student t test or SNK-q test was used for comparison. Results:VAP group had elevated percentage of circulating CD14 +A20 + cells than control group [(66.14±19.62)% vs. (52.52±13.71)%, P<0.05], and also had increased A20 mean fluorescence intensity (MFI) than control group [(268.0±72.56) vs. (197.4±60.01), P<0.05]. The percentage of CD14 +A20 + cells in BALF from infection site was higher than from non-infection site in VAP group [(66.14±19.62)% vs. (52.52±13.71)%, P<0.05], while A20 MFI in infection site was also up-regulated compared with non-infection site [(268.0±72.56) vs. (197.4±60.01), P<0.05]. In direct contact co-culture, A20 siRNA transfected CD14 + monocytes, which were purified from peripheral blood and BALF of VAP patients, induced elevated percentage of IFN-γ and IL-17 secreting CD4 + T cells than un-transfection or control siRNA transfection ( P<0.05). However, there were no significant differences of CD4 +IFN-γ + or CD4 +IL-17 + percentages among un-transfection, control siRNA transfection, and A20 siRNA transfection ( P>0.05). A20 siRNA transfected CD14 + monocytes, which were purified from peripheral blood and BALF of VAP patients, induced increased target cell death in both direct and indirect contact co-culture than un-transfection or control siRNA transfection ( P<0.05). Tumor necrosis factor-α, IL-6, granzyme B level and TRAIL MFI was also up-regulated ( P<0.05). There was no remarkable difference of target cell death between direct and indirect contact co-culture ( P>0.05). Conclusions:A20 was increasingly expressed in monocytes of VAP patients, and might dampen the activity of monocytes.
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ObjectiveTo develop doxorubicine-loaded nanomicelles based on a type of novel starshaped 4-arm PLGA-PEG-NH2 amphiphilic block copolymers.Methods 4s-(PLGA-PEG-NH2) synthesized by 4s-PLGA and (H2N-PEG-NH2) according to N,N'-dicyclohexylcarbodiimide(DCC) condensation reaction was demonstrated by 1H NMR spectroscopy and gel permeation chromatography(GPC); DOX-loaded 4s-(PLGA-PEG-NH2) nanomicelles were self-assembled by doxorubicin(DOX) and 4s-(PLGA-PEG-NH2) via emulsion-solvent evaporation method and characterized in terms of morphology,particle size and size distribution,drug loading,encapsulation efficacy,cell uptake and cytotoxicity studies.Results4s-(PLGA-PEG-NH2) were capable of selfassembling intocore-shell nanomicelles structure and encapsulating DOX into their hydrophobic cores.The mean size of DOX-loaded 4s-(PLGA-PEG-NH2) was nanometer size; drug loading and encapsulation efficacy were around 7.5％ and 75.2％,respectively.Mean surface charge of the micelles was around -17.6 mV.In vitro cell uptake and cytotoxicity studies indicated that comparing to the DOX-loaded linear-(PLGA-PEG-PLGA)nanomicelles,DOX-loaded 4s-(PLGA-PEG-NH2) nanomicelles showed better performance in uptaking by HeLa cells and higher cytotoxicity to cancer cells.Conclusion4s-(PLGA-PEG-NH2) amphiphilic block copolymers can be successfully used in encapsulating DOX,self-assemblingcore-shell nanomicelles in aqueous solvent.Therefore,4s-(PLGA-PEG-NH2) copolymers can be considered as a promising drug carrier in effectively carrying hydrophobic drug,improving the efficacy while reducing the side effect.