Effects of liver regeneration on the proliferation of rat fetal hepatocytes after intrasplenical transplantation

AIM:To study the effect of environment of liver regeneration on the proliferation of rat fetal hepatocytes after intrasplenical transplantation. METHODS:Fetal hepatocytes isolated from 3-week SD rat fetuses bred were transplanted into the spleens of liver regeneration model rats with 70% partial hepatectomy. The cell cycle of the hepatocytes in the remnants liver was analyzed by flow cytometer and the density dimensions of the donor fetal hepatocytes in spleen were measured by image analysis system 7 and 30 days post-transplantation, respectively. RESULTS:Compared with the control group, the proportions of S and G₂ /M cells in the remnants liver were obviously decreased (P＜0.05), but the density dimensions of the donor fetal hepatocytes in spleen increased significantly (P＜0.05) in rats with hepatectomy 7 days post-transplantation. CONCLUSION:The environment of liver regeneration is propitious to the proliferation of fetal hepatocytes after transplantation into spleen.     

Changes of Ca2＋ activated potassium channels and cellular-proliferation in autogenous vein grafts

AIM: To investigate changes of Ca^2＋ activated potassium channels (K_Ca) in autogenous vein grafts. METHODS: The contraction of venous ring was measured by means of perfusion in vitro. The intimal proliferation and proliferation of cultured smooth muscle cells (vascular smooth muscle cells, VSMCs) were observed by the means of computerised image analysis and MTT method, respectively. Furthermore, whole cell mode of patch clamp was used to record K_Ca of VSMCs isolated from autogenous vein grafts. RESULTS: 1 week after transplantation there were no significant differences of contraction and intimal relative thickness between autogenous vein grafts and control. Contraction and intimal relative thickness of autogenous vein graft were significantly increased 2 weeks after transplantation (P＜0.05, n=8 vs control), and they were more enhanced 4 weeks after vein transplantation (P＜0.01, n=8 vs control). TEA (blocker of Ca^2＋ activated potassium channels) increased MTT A₄₉₀ value of VSMCs from femoral vein in a dose-dependent manner (P＜0.05, n=8). K_Ca current density was significantly attenuated in VSMCs from autogenous vein grafts 1-4 weeks after transplantation (P＜0.05, n=5). CONCLUSION: K_Ca was inhibited in autogenous vein graft, which accounted for vasospasm and intimal proliferation.     

朱砂根穴盆苗育苗及移植技术研究

朱砂根苗木生产是朱砂根产业化的基础,通过选择不同类型的穴盆进行育苗试验,比较不同类型穴盆育苗对朱砂根出苗率、存活率、苗木叶片的影响;通过对穴盆苗不同时期的移植试验,选择穴盆苗最佳移植时间。     

我国大树移植的现状与对策

上世纪未,伴随我国城市建设和城市绿化高速发展而来的滥挖滥移大树的歪风吹遍中华大地,使我国脆弱的生态系统雪上加霜,严重破坏了大树原生地的生态环境,制造了一大堆城市“景观垃圾”,同时也突显了我国苗圃技术和苗圃建设严重滞后的现实。几年以来,作者利用工作之便,对广东、浙江、上海、福建、海南、湖南等地的部分苗圃和城市绿地就“大树移植”问题进行了调研,收集了大量的资料、数据和现场照片;着重分析了这股歪风的缘起、发展和危害;并就如何解决这一问题作了深入的探讨,提出了一些对策和建议。     

单杆芦荟离体快速繁殖技术研究

单杆芦荟离体快速繁殖，芽增殖培养基以MS＋BA2．5mg/L NAA0.2-0.3mg/L，生根培养基以1／2MS＋NAA 2.0mg/L 活性炭0．2％－0．3％，壮苗培养基以1／2MS＋IBA2.0mg/L为好。培养温度以28℃最佳。快速繁殖方法用分叶法比常用的分株、分芽方法，繁殖系数高。培养出的壮苗移栽于河沙中，成活率一般在80％以上。     

Cell-cycle-dependent Colonization of Mouse Spermatogonial Stem Cells After Transplantation into Seminiferous Tubules

Spermatogonial stem cells (SSCs) migrate to the niche upon introduction into the seminiferous tubules of the testis of infertile animals. However, only 5–10% of the transplanted cells colonize recipient testes. In this study, we analyzed the impact of cell cycle on spermatogonial transplantation. We used fluorescent ubiquitination-based cell cycle indicator transgenic mice to examine the influence of cell cycle on SSC activity of mouse germline stem (GS) cells, a population of cultured spermatogonia enriched for SSCs. GS cells in the G1 phase are more efficient than those in the S/G2-M phase in colonizing the seminiferous tubules of adult mice. Cells in the G1 phase not only showed higher expression levels of GFRA1, a component of the GDNF self-renewal factor receptor, but also adhered more efficiently to laminin-coated plates. Furthermore, this cell cycle-dependency was not observed when cells were transplanted into immature pup recipients, which do not have the blood-testis barrier (BTB) between Sertoli cells, suggesting that cells in the G1 phase may passage through the BTB more readily than cells in the S/G2-M phase. Thus cell cycle status is an important factor in regulating SSC migration to the niche.     

园林大树夏季全冠移植的几项关键技术

园林大树夏季全冠移植是现阶段园林绿化建设的常用手段,通过分析大树移栽的几个关键技术,认为铁勾网包扎可代替木箱移植,抗蒸腾剂技术应深入研究推广,成熟后可用于代替全光喷雾技术。易积水的移栽地可使用根部土壤透气技术。营养液滴注技术使用时应注意输液孔处病虫害的侵袭。文章总结提出了断根处理、树干钉板、根部固定和浇水节律等配套技术,可为园林大树夏季全冠移植工作提供参考。     

大通红松大田移植育苗技术

2013年进行了红松大田移植育苗试验,本文介绍了红松大田育苗的整地做床、栽培及苗期管理等技术。     

柑桔三倍体苗的试管嫁接及微繁殖研究

甜橙胚乳三倍体试管苗茎段及顶芽采用试管扦插培养难于生根,亦不能正常生长;而将其茎段和顶芽嫁接于试管中的砧木上,成苗率达90％以上。在含BA0.1mg/L的MT培养基中,每株嫁接苗形成3～4个芽,可作试管快速繁殖。嫁接苗移植于无菌土中,成活率高达95％以上。田间二重接可加速三倍体小苗生长。本方法为解决柑桔试管苗移植问题提供了一条新途径。