拉萨市某三甲医院院内感染及多重耐药菌感染特点分析

目的了解院内感染及多重耐药菌(MDROs)感染特点。方法对2016年10月~2017年6月入院所有患者进行前瞻性调查,调查医院感染及多重耐药菌感染情况。结果全院15674例患者中发生医院感染100例,医院感染率为0.64%;ICU感染率最高(13.90),明显高于其他科室(P<0.001);感染部位主要为呼吸道和手术部位;47株医院感染病原体以大肠埃希菌(23.40%)鲍曼不动杆菌(23.40%)和肺炎克雷伯菌(17.02%)为主。MDROs总的检出率为14.19%;以CR-AB和MRSA检出率最高,分别为71.43%和42.59%,而且这两种MDRO也是医院感染主要病原体。结论医院感染防控的重点为呼吸道感染,应重视抗菌药物合理使用,并贯彻多重耐药菌防控措施。

Tyrosine Induces Anthocyanin Biosynthesis in <i>Arabidopsis thaliana</i>

Anthocyanins are widely found in plants and are responsible for the purple coloration of plants. Anthocyanin biosynthesis is induced by environmental stresses, plant hormones, sugar, and so on. Tyrosine (Tyr) is the precursor of melanin that exits in both animals and plants. However, until now it has been unknown whether Tyr induces anthocyanin biosynthesis. In this study, the seedlings of Arabidopsis thaliana were treated with exogenous Tyr and then the anthocyanin accumulation was determined. The results showed that Tyr induced anthocyanin accumulation in Arabidopsis thaliana in a dose-dependent manner. Furthermore, the expression of the late anthocyanin biosynthetic genes including DFR, LDOX, and UF3GT, and the transcription factor genes PAP1, PAP2, and EGL3 was induced by Tyr. Taken together, these results demonstrated that Tyr is able to induce anthocyanin accumulation and suggested that Tyr up-regulates transcription factors PAP1, PAP2, and EGL3, which mediates the expression of the late anthocyanin biosynthetic genes and then induces anthocyanin biosynthesis.

Sucrose Enhances Tyrosine-induced Inhibition of Growth in Arabidopsis Seedlings

Tyrosine (Tyr) and sucrose (Suc) play an important role in plant growth.However,the crosstalk between Tyr and Suc in regulating the plant growth has remained unclear.In this study,it was found that Suc is able to enhance Tyr-induced inhibition of growth in Arabidopsis seedlings.Both fresh weight and root length of Arabidopsis seedlings were significantly reduced when the medium was added with high concentrations (such as 0.5 or 1.0 mM)of Tyr whereas they were clearly increased with an addition of appropriate concentrations of Suc (such as 1 or 3%) in the medium,which suggested that the growth of Arabidopsis seedlings is inhibited by high concentrations of Tyr but promoted by appropriate concentrations of Suc.Interestingly,the inhibition of growth in Arabidopsis seedlings by 0.5 or 1.0 mM Tyr was significantly intensified once 1%or 3%of Suc was added in the medium.This study revealed a positive effect of Suc on the Tyr-induced inhibition of plant growth,and the results help us to further investigate the crosstalk of Suc and Tyr in the regulation of plant growth.

Source rupture model of the 2018 M_(W)6.7 Iburi,Hokkaido earthquake from joint inversion of strong motion and InSAR observations

The 2018 M_(W)6.7 Iburi earthquake shocked the eastern Iburi region to the west of the Hidaka Collision Zone in Hokkaido,which is a destructive inland earthquake.We resolved the kinematic rupture process of the event by combining strong motions(SM)and synthetic aperture radar(SAR)images in a joint inversion.The results reveal that the duration of the whole rupture is about 17s,yielding a total seismic moment of 1.4×10^(19)N·m(M_(W)=6.7).The main slip area is located at a depth of approximately 24 km with a peak slip of~0.8m above the hypocenter.The comparison with the regional velocity model shows the earthquake was initiated in the upper mantle,while the majority of slips are located in the lower crust,which is an“aseismic”domain in the typical sandwich model.The location of the major slip area is consistent with a high-conductivity volume.We proposed a mechanism of low frictional property(<0.3)produced by high pore pressure to explain the abnormal high dip angle and centroid depth located in the ductile lower-crust.Aftershocks are distributed in areas where the Coulomb frictional stress increases due to co-seismic displacement with a mechanism conjugating to the mainshock.

Study on In vitro Regeneration System of Melon

[ Objective] This study aimed to optimize the in vitro regeneration system of melon. [ Method] Melon variety Nanxiang91023 was selected as experi- mental materials, with the cotyledons and hypocotyls as explants, different types and concentrations of growth regulators were supplemented at different stages of tis- sue culture, to explore the simple and effective medium formula for regeneration of melon. [ Result] MS ＋ 1.5 mg/L of 6-BA ＋0.2 mg/L of LAA was the optimal medium for induction and proliferation of callus; MS ＋ 1.0 mg/L of 6-BA ＋ 0. 2 mg/L of 2, 4-D was the optimal medium for differentiation of adventitious buds; MS ＋ 1.0 mg/L of ZT ＋ 0.2 mg/L of LAA was the optimal medium for rooting of seedlings. On the basis of above conditions, melon seedlings had high roofing rate and strong roots. [ Conclusion] This study provided a guarantee for the further genetic transformation of improved melon varieties.

Brassinosteroid Enhances Jasmonate-Induced Anthocyanin Accumulation in Arabidopsis Seedlings

Jasmonate （JA） regulates plant development, mediates defense responses, and induces anthocyanin biosynthesis as well. Previously, we isolated the psc1 mutant that partially suppressed coi1 insensitivity to JA, and found that brassinosteroid （BR） was involved in JA signaling and negatively regulated JA inhibition of root growth in Arabidopsis. In this study it was shown that JA-induced anthocyanin accumulation was reduced in BR mutants or in wild type treated with brassinazole, an inhibitor of BR biosynthesis, whereas it was induced by an application of exogenous BR. It was also shown that the‘late’anthocyanin biosynthesis genes including DFR, LDOX , and UF3GT, were induced slightly by JA in the BR mutants relative to wild type. Furthermore, the expression level of JA-induced Myb/bHLH transcription factors such as PAP1, PAP2, and GL3, which are components of the WD-repeat/Myb/bHLH transcriptional complexes that mediate the ‘late’ anthocyanin biosynthesis genes, was lower in the BR mutants than that in wild type. These results suggested that BR affects JA-induced anthocyanin accumulation by regulating the ‘late’ anthocyanin biosynthesis genes and this regulation might be mediated by the WD-repeat/Myb/bHLH transcriptional complexes.