Selection of culture conditions for callus induction and proliferation by somatic embryogenesis of Pinus koraiensis

The induction and proliferation of embryogenic callus are key steps for large-scale propagation of somatic embryogenesis pathway and long-term preservation of coniferous germplasm.Callus can be induced from immature embryos of Korean pine(Pinus koraiensis Sieb.et Zucc.;Pinaceae)as explants,but there are problems,such as low proliferation efficiency,loss of embryogenicity,poor vigor;thus,best conditions for proliferation and culture of immature embryos of Korean pine are not yet clear.To solve the problems with somatic embryogenesis of Korean pine and determine the best culture conditions for callus induction and proliferation,we varied hormone concentration,subculture cycle of proliferation and other plant growth regulators combinations in media to induce callus formation by megagametophytes of three Korean pine families at different developmental stages,then analyzed the effects on embryogenic callus retention and cell proliferation using a quadratic regression orthogonal rotation design.The results showed that the family origin and collection date of explants significantly affected callus induction(induction rate reached 1.67%).Embryogenic maintenance and callus proliferation were best on DCR medium supplemented with 0.25 mg L^(−1)6-benzyl adenine,1 mg L^(−1)naphthaleneacetic acid,30 g L^(−1)sucrose,500 mg L^(−1),L-glutamine,500 mg L^(−1)casein hydrolysis and 6.5 g L^(−1)agar.In addition,the combination of 2,4-dichlorophenoxyacetic acid+6-benzyl adenine also had a better proliferative effect on callus.The effects of different combinations of growth regulators on callus proliferation efficiency were significantly different.Transfer to new medium every 13–15 days not only maintained robust callus vigor,but also yielded a larger proliferation coefficient.The techniques and conditions for embryogenic callus induction and proliferation of Korean determined here will serve as a foundation for establishing a large-scale system for somatic embryogenesis and propagation of Korean pine.

Factors influencing the degree of participation in surgical decision-making among Chinese patients with prostate cancer:A qualitative research

Objective:There was increasingly demand of participation in surgical decision-making among Chinese patients with prostate cancer.However,due to the complex healthcare system and advanced care settings,it is quite challenging for the patients to gain sufficient support from the institute and the government.This research aimed to investigate the factors that impact the degree of participation in surgical decision-making among Chinese prostate cancer patients.Methods:A phenomenological approach of qualitative research based on the results of semi-structured interviews was adopted,to explore the influencing factors which hinder the participation in surgical decision-making.Consolidated Criteria for Reporting Qualitative Research were utilized.Up to 160 post-operative patients who had undergone radical prostatectomy along with 68 medical and nursing staffs,were purposively recruited in this research.This retrospective study was carried out from September 2018 to August 2019.After recording and transcribing the interviews,the interview materials were evaluated via the Colaizzi's seven step approach and the NVivo Version 10 software to analyze the interview content.Results:According to the analysis and summary of the interviews,there were three factors affecting the degree of participation in surgical decision-making.Firstly,insufficient information was provided by medical and nursing staffs because of their lack of time,proper communication skills,and career experience,as well as difficulties in the development of patient decision aid and inconsistent resource availability.Secondly,the cognitive level of decision-making among patients was relatively low due to poor psychological endurance,insufficient amount of education,senility,and less knowledge and information demand.Ultimately,decisions were constantly made by family members with/without patients.Conclusions:The degree of participation of Chinese prostate cancer patients in the surgical decision-making had much space for improvement.

Suspension Culture and Somatic Embryogenesis of Korean Pine

Korean pine is an important afforestation tree species in Northeast China,which has a high ecological and economic value.Although regeneration of somatic embryogenesis using immature zygotic embryos of Korean pine as explants has been successful,it cannot be applied to automation and large-scale production.Therefore,we urgently need a method that can increase the output of somatic embryos(SEs)to meet the needs of large-scale production.We used Korean pine 1-1 and 1-100 cell lines as research materials to evaluate the effects of inoculum-density,culture time,orbiting speed,vessel volume,plant growth regulator(PGR)concentration,and carbon source on the proliferation of embryogenic tissue(ET).The somatic embryogenesis ability of ET cultured in different liquid suspension media was also evaluated.We found that during liquid suspension culture of Korean pine ET,the sedimented cell volume(SCV),fresh weight(FW)and dry weight(DW)were affected by inoculumdensity,culture time,orbiting speed,2,4-D concentration,6-BA concentration and carbon source type.Fourty mg⋅mL^(−1)ET were transferred to a 200 mL Erlenmeyer flask containing 20 mL liquid medium,and cultured at 100 rpm/min for 14 days to obtain the maximum proliferation.In addition,we also found that SCV,FW and DW were higher when PGRs were reduced in the liquid suspension medium.The substitution of maltose for sucrose resulted in slow growth of cultures and limited SE yield(13 SEs g^(−1)FW).Although culture proliferation was high at 50 rpm,SE yield was inhibited by 48%compared with 100 rpm(50 rpm=33 SEs g^(−1)FW;100 rpm/min=70 SEs g^(−1)FW).Cultivation in low-concentration PGR(1.15μM⋅L^(−1)2,4-D,0.25μM⋅L^(−1)6-BA)and sucrose liquid medium at 100 rpm/min(80 SEs g^(−1)FW)could not only promote culture proliferation but also increase SE yield.The determination of the suspension culture scheme of Korean pine ET provides a reference for further expansion to bioreactor culture in the future and lays a foundation for the automation and scale of somatic embryogenesis of Korean pine.

不同构型挡板搅拌槽内液-液分散特性

以水和煤油为研究体系,利用数值模拟方法研究了标准挡板(Standard Baffle,SB)、标准穿流挡板(Standard Punched Baffle,SPB)和之字形穿流挡板(Zigzag Punched Baffle,ZPB)搅拌槽内液-液分散特性。结果表明,采用之字形穿流挡板可有效降低搅拌槽内挡板后方的死区。随着搅拌转速增加,三种挡板搅拌槽的搅拌功耗逐渐增大,煤油液滴直径逐渐减小。在相同搅拌转速下,之字形穿流挡板搅拌槽内液滴直径均小于标准挡板和标准穿流挡板。随着搅拌转速增加,ZPB和SPB搅拌槽内的液滴直径与SB搅拌槽的差距均呈现先增大后减小的趋势,当搅拌转速为400 r/min时,差异最大。此时,相较于SB搅拌槽,SPB和ZPB搅拌槽内液滴直径分别减小18.16%和36.87%。