带血管蒂髌腱移植物的力学性能

背景：临床上研究膝关节交叉韧带生物材料的力学性能具有重要意义,可为临床研制组织结构、生物力学及相容性好的材料提供理论依据。目的：分析带血管蒂髌腱移植物的力学性能。方法：切断42只新西兰大白兔左前腿前交叉韧带,随机分为2组,实验组植入自体带血管蒂髌腱移植物进行前交叉韧带修复,对照组植入自体不带血管蒂髌腱移植物进行前交叉韧带修复。移植后8,12,16周,检测两组移植标本的生物力学性能。结果与结论：两组不同时间点的断裂位置比较差异无显著性意义;实验组移植后12,16周的膝关节前后松弛度高于对照组(P < 0.05),两组移植后8周的膝关节前后松弛度比较差异无显著性意义;实验组移植后8,12,16周的最大载荷均高于对照组(P < 0.05),移植后8,12,16周的刚度均高于对照组(P < 0.05);两组移植后不同时间点的最大拉伸长度比较差异无显著性意义。表明带血管蒂髌腱移植物具有良好的力学性能。 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

枸杞多糖对胎儿卵巢组织冷冻保存的影响

背景：抗氧化剂的应用对于提高卵巢组织冻存后的活力起着很重要的作用。 目的：通过观察冷冻保存的胎儿卵巢组织异种移植到裸鼠肾被膜下的发育情况,探索枸杞多糖在卵巢组织冷冻保存中的作用。 方法：实验分为4组。①新鲜移植组：取材后的新鲜胎儿卵巢组织直接进行移植。②冻存对照组：冷冻保护液为基液。③β-巯基乙醇组：冷冻保护液为基液添加100 μmol/L β-巯基乙醇。④枸杞多糖组：冷冻保护液为基液添加 400 mg/L枸杞多糖。对冷冻复温后的胎儿卵巢皮质块进行祼鼠的肾被膜下移植,并于移植后12周取材。 结果与结论：各组在移植物的存活率上差异无显著性意义(P > 0.05)。在卵泡计数上冷冻对照组最低(P < 0.05)。在卵泡的存活率上,各组间差异均有显著性意义,其中以冷冻对照组最低,枸杞多糖组最高。β-巯基乙醇组和枸杞多糖组卵巢超微结构较冷冻对照组保存的好。提示400 mg/L的枸杞多糖和100 μmol/L的β-巯基乙醇有利于卵巢组织的冷冻保存,并可显著提高冷冻卵巢组织移植后的存活率。     

Caspase抑制剂对冻融卵巢组织的影响

目的研究Caspase抑制剂z-DEVD-fmk对冻融小鼠卵巢组织的影响。方法将15只小鼠随机分为3组：A组（新鲜对照组）、B组（添加z-DEVD-fmk组）和C组（未添加z-DEVD-fmk组）,B组和C组的卵巢组织进行玻璃化冷冻,一部分卵巢皮质组织进行组织学分析,另一部分卵巢皮质组织进行自体移植,手术后1个月后测血清雌二醇浓度和移植物增值细胞核抗原（PCNA）表达率。结果光镜观察发现冷冻组的始基卵泡和初级卵泡的形态正常率均明显低于对照组,B组的始基卵泡和初级卵泡的形态正常率与C组比较无明显差异。然而,B组血清雌二醇浓度高于C组,差异有统计学意义。同样,B组移植物卵细胞和间质细胞PCNA蛋白表达率高于C组。结论实验结果提示：Caspase抑制剂z-DEVD-fmk在卵巢组织冻融过程中具有保护作用。     

大鼠冻存卵巢组织自体异位移植后长期功能评估

目的 评估成年大鼠冻存卵巢组织自体异位移植后的长期生殖、内分泌功能. 方法 78只Wistar成年大鼠,随机分为假手术组(1组,15只)、新鲜组织移植组(2组,24只)、冻存组织移植组(3组,24只)、去势组(4组,15只).将去势后成年大鼠的新鲜卵巢组织及冻存卵巢组织自体异位移植于肾被膜下,分别于移植后5、8、10个月处死各处理组1/3数量动物,取卵巢及子宫组织作组织学检查.通过阴道脱落细胞学检查、动情期雌、孕激素水平监测评估移植后卵巢组织的生殖内分泌功能. 结果 所有动物模型中,新鲜及冻存卵巢组织移植后都可观察到存活组织块.2、3组动情期雌、孕激素水平与假手术组无显著性差异(P>0.05),且均明显高于去势组(P<0.01).冷冻复苏后组织与新鲜组织各级卵泡构成比无显著性差异(P>0.05),各组不同时间取得的卵巢组织各级卵泡构成比相比较均无显著性差异(P>0.05).移植后5个月,2、3组原始卵泡明显减少,分别为假手术组的59.1%和54.5%. 结论 小块卵巢组织可耐受冻融过程;冻存卵巢组织自体肾被膜下移植后,卵巢组织形态无明显改变,原始卵泡总数虽然明显减少,但有成熟卵泡发育并排卵,并能长期维持生殖内分泌功能.     

冻融囊胚及冻融胚胎养囊胚后移植的临床效果分析

目的探讨新鲜胚胎行囊胚培养后冷冻,再经囊胚复苏移植与冻融胚胎复苏后再行囊胚培养形成囊胚后移植的效率比较。方法解冻后有2个以上的II级胚胎或者Ⅲ级胚胎超过4个者行囊胚培养,形成3CC以上囊胚则进行移植,同期将新鲜卵裂期胚胎移植或冷冻部分优胚后剩余的胚胎进行囊胚培养,形成3CC以上的囊胚进行冷冻,再次复苏囊胚移植。结果冻融胚胎解冻行囊胚培养共139个周期,解冻存活694个胚胎,形成3CC以上囊胚228个,囊胚形成率32.85%,有囊胚形成的119个周期,移植118个周期,移植妊娠率和种植率分别为41.5%和30.2%,同期进行新鲜剩余胚胎的囊胚培养141个周期共1204个胚胎,形成3CC以上的囊胚386个,有囊胚形成的128个周期进行冷冻,解冻移植38个周期,移植妊娠率和种植率分别为50.0%和35.7%。结果解冻囊胚移植的妊娠率与种植率比解冻后养囊胚获移植的妊娠率与种植率高,但两组无统计学差异。新鲜胚胎养囊胚和冻融胚胎复苏后养囊胚的形成率和取消率没有统计学差异。结论经历多次优质胚胎移植后妊娠失败的患者可考虑将复苏胚胎行囊胚培养后移植囊胚来改善妊娠结局;在新鲜周期移植冷冻部分优胚后剩余的胚胎行囊胚培养后再冷冻,可提高胚胎的有效利用率。     

玻璃化法处理同种异体动脉的移植

背景:体外血管预处理及保存方法有多种,经过学者们长期大量的研究观察,各种方法均得到了改进,但是仍然存在弊端。因此找到一种更有效的或者几种体外血管预处理保存方法的结合,还需要大量的研究实践。目的:拟通过比较玻璃化法和传统冷冻法保存处理的同种异体血管移植后效果,找出一种更为实用且制作简便的血管处理方法。方法:选用健康青紫兰兔96只,手术切除双侧股动脉,根据不同体外血管预处理方法将实验分为3组,即新鲜血管自体移植组、冷冻+辐照预处理血管同种异体移植组及玻璃化+辐照预处理血管同种异体移植组。血管移植后1,2,8,12周,每组取6只动物进行腹主动脉数字减影血管造影、扫描电子显微镜、组织病理学观察,观察移植血管通畅率、动脉瘤形成情况及组织形态学变化。结果与结论:移植后12周,新鲜血管自体移植组血管的累计通畅率显著高于冷冻+辐照预处理组(P0.05),玻璃化+辐照预处理组与其他两组比较,差异无显著性意义(P0.05)。组织病理学检查显示,玻璃化+辐照处理的同种异体血管内膜及中层平滑肌增生较冷冻+辐照预处理组轻,管腔狭窄不明显,炎症反应较轻。经玻璃化法+辐照保存的同种异体血管制作程序简单,移植血管通畅率高,组织反应轻,是一种比较理想的同种异体血管体外处理方法。     

冻融单囊胚移植在IVF高获卵患者中的应用

目的探讨冻融单囊胚移植在高获卵患者中的应用价值。方法回顾性分析2013年2月至2014年2月460例体外受精高获卵患者的临床资料,按移植方案不同分为3组:A组:移植新鲜细胞期胚胎者120例;B组:移植新鲜单囊胚者160例;C组:将胚胎行囊胚培养,冷冻后择期行冻融单囊胎移植者180例。比较3组患者的超促排卵方案、妊娠率、着床率、OHSS发生率及其他并发症情况。结果 3组患者的超排卵方案及早期流产率比较,差异均无统计学意义(P0.05)。冻融单囊胚组着床率及妊娠率与高于其他两组,差异有统计学意义,且异位妊娠率及多胎率低于新鲜胚胎组,差异均有统计学意义(P0.05);3组间早发OHSS率比较无明显差异,冻融单囊胎组避免了迟发型OHSS的发生,与其它两组比较,差异有统计学意义(P0.05)。结论高获卵患者行冻融单囊胚移植在保证较高妊娠率的同时减少了OHSS发生率、异位妊娠率及多胎率。     

不同冷冻方案保存人类卵巢组织的活性比较

背景：卵巢组织冷冻保存被认为是保存女性生殖内分泌功能安全、有效的方法,但目前尚无统一确定的方案。目的：探讨3种冷冻方案对人类卵巢组织保存冷冻效果及卵泡活性的影响。方法：采用丙二醇慢速程序冷冻法、二甲基亚砜玻璃化冷冻法、液氮直投法对20例人类卵巢组织进行冷冻保存,复苏后采用细胞存活/死亡荧光分析法计数有活性的细胞,体外培养测定培养液雌二醇浓度及各级卵泡计数,判断3种不同冷冻方案对人类卵巢组织活性的影响。结果与结论：不同冷冻方案冻融后卵巢组织块的活性卵泡率均低于新鲜卵巢组(P < 0.05),二甲基亚砜组最低,液氮直投法组与慢速程序冷冻法组差异无显著性意义。体外培养各冷冻组分泌的雌二醇水平比较,第4天时二甲基亚砜组低于液氮直投法组和慢速程序冷冻法组(P < 0.05),至第8天时各冷冻组雌二醇水平与新鲜卵巢组一致。培养14 d组织学观察,各组卵巢组织内生长期卵泡比例增多,始基卵泡仍然占最主要的。新鲜卵巢组织正常卵泡的总数高于冷冻组(P < 0.05),二甲基亚砜组的正常卵泡数低于液氮直投法组和慢速程序冷冻法组(P < 0.05)。提示冷冻保存对卵巢组织卵泡有一定的损伤,但仍能保存大部分始基卵泡的活性,经体外培养后可进一步发育并具有分泌功能,在3种冷冻方案中,慢速程序冷冻法和液氮直投法的冷冻效果优于二甲基亚砜玻璃化冷冻法,液氮直投法操作简便,冷冻效果稳定。 中国组织工程研究杂志出版内容重点：肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程全文链接：     

纤维蛋白胶介导内皮祖细胞再生心肌梗死血管的可行性

背景:有研究显示纤维蛋白胶可促进成肌细胞移植物的保持和生存,减少梗死范围并在梗死区诱导新生血管化。目的:了解内皮祖细胞经可降解材料纤维蛋白胶移植到大鼠梗死心肌后的血管再生情况。方法:将27只SD大鼠随机均分为3组,非心肌梗死组9只、心肌梗死即刻移植组9只与心肌梗死1周移植组9只。每个大组又再分为两个亚组,即移植人脐带源内皮祖细胞-纤维蛋白胶复合物的实验组与移植纤维蛋白胶的对照组。移植后3,8周处死,通过显微镜、免疫组织化学和心脏超声观察其在梗死心肌的血管再生和心功能改善情况。结果与结论:显微镜观察到,实验组大鼠心脏和胸部之间有一些疏松的结缔组织,而其与对照组之间无明显差异。组织和免疫学观察发现,各实验组和对照组的心脏结构不易区分且相对正常,未发现血管瘤、血管畸形和肿瘤等。血管测量结果显示实验组和对照组之间,以及各实验组之间均无差异,并且实验组和对照组之间心功能检查也没有统计学意义。此次研究内皮祖细胞结果没有阳性表现,将修改并提高细胞通过纤维蛋白基质传递的方法策略,确信细胞传递系统提供的有益性和有效性将会进一步得到证实。     

人胎儿卵巢组织异种移植的实验研究

目的探讨人胎儿卵巢组织异种移植后的卵泡生长发育情况。方法28只裸鼠行去势手术后分为3组:O组为对照组;A组为新鲜胎儿卵巢组织移植组;B组为冻融人胎儿卵巢组织移植组。A、B两组均于移植1个月后开始隔天注射5 IU的PMSG持续2个月,获取移植物36h前注射HCG。将获取胎儿卵巢组织进行光学显微镜的观察并测各组血清雌二醇(E2)的浓度。结果A、B两组血清E2水平明显高于O组,差异有显著性(P<0.01),A、B两组间无显著性差异(P>0.05)。移植后存活的卵巢组织中有40%~50%的原始卵泡丢失。A、B两组织中均以原始卵泡为主,可见少量初级卵泡和次级卵泡,未见窦卵泡的生长。移植后人胎儿卵巢组织中初级卵泡和次级卵泡的比例较移植前显著增加(P<0.01),A、B两组相比各级卵泡比例无显著性差异(P>0.05)。结论冻融人胎儿卵巢组织移植于裸鼠的背部皮下能存活,其卵泡处于良好的生长发育状态。     

Antigenicity of cryopreserved arterial allografts: comparison with fresh and glutaraldehyde treated grafts

The use of cryopreserved aortic allografts in cardiovascular surgery is widespread and has resulted in excellent outcomes. However, it is controversial whether cryopreservation suppresses the antigenicity of tissue. We designed experimental models to study whether the cryopreservation process alters antigenicity in comparison with that found in fresh and glutaraldehyde treated tissues. Fresh, cryopreserved, and glutaraldehyde treated thoracic aorta from Brown Norway rats were subcutaneously implanted into Lewis rats. Inflammatory cells infiltrating around the grafts were measured on days 7, 14, 28, and 56 after implantation. The glutaraldehyde treated grafts showed significantly less infiltration than the fresh or cryopreserved grafts (p < 0.005). No significant difference was detected between the fresh and cryopreserved grafts. Another study examined the effect of modifications of the aortic allograft on subsequent allogeneic skin graft antigenicity. Subcutaneous implantation of fresh, cryopreserved, and glutaraldehyde treated aortic grafts from Brown Norway into Lewis rats resulted in subsequent skin graft rejection at 4.4+/-0.7, 5.1+/-0.8, and 6.6+/-2.1 days, respectively. There was no significant difference between the fresh and cryopreserved groups; whereas skin grafts in the glutaraldehyde group survived longer than those in the cryopreserved group. These results indicate that cryopreservation had no significant influence on antigenic suppression of arterial allografts.     

Comparison of adrenal and foetal nigral grafts on drug-induced rotation in rats with 6-OHDA lesions

Summary Separate groups of rats with unilateral 6-OHDA lesions of the nigrostriatal pathway received intrastriatal foetal (E14) substantia nigra suspension grafts, intrastriatal postnatal (P22–25) adrenal medulla suspension grafts using either collagenaseor trypsin-based dissociation procedures, intraventricular adrenal medulla grafts, or remained with lesions alone. Rats with nigral or adrenal suspension grafts, but not rats with adrenal solid grafts, showed reduced apomorphine-induced rotation in comparison with lesion rats. The nigral graft group alone showed substantial reduction of amphetamine-induced rotation, and this was the only group manifesting good long-term graft survival. These results indicate that nigral and adrenal grafts do not have comparable mechanisms of functional action, and suggest that adrenal grafts can ameliorate apomorphine-induced rotation by a non-specific mechanism.     

Cografts of adrenal medulla with C6 glioma cells in rats with 6-hydroxydopamine-induced lesions

Amitotic [3H]thymidine-labeled C6 glioma cells, which are known to produce neurotrophic factor(s), were grafted alone and with adrenal chromaffin cells in an attempt to improve chromaffin cell survival and phenotypic differentiation. Long-Evans rats with unilateral 6-hydroxydopamine-induced lesions of the nigrostriatal pathway were divided into four groups: (1) those receiving adrenal medullary cells co-transplanted with C6 glioma cells; (2) those receiving adrenal medullary graft alone; (3) those receiving C6 glioma grafts alone; and (4) those serving as a vehicle control group. All rats were killed one month after transplantation. Immunohistochemical, neurochemical, and autoradiographic methods were used to identify and characterize the grafted cells. Tyrosine hydroxylase-immunoreactive cells were found in all animals that received grafts of the adrenal medulla alone or of adrenal medulla co-transplanted with C6 glioma cells. The cograft recipients had more tyrosine hydroxylase-immunoreactive cells than the hosts receiving just adrenal chromaffin cells (P less than 0.05). Additionally, more grafted chromaffin cells formed processes in the former group. All three tissue recipient groups (adrenal medullary, C6 glioma cell, and cografted animals) had a significant reduction (P less than 0.05) in ipsilateral rotations after amphetamine (0.5 mg/kg i.p.) injections as compared to the control vehicle recipient group. Moreover, the reduction in rotation was more marked in the cografted hosts than in the other two implanted groups (P less than 0.05). Significantly higher dopamine levels were found in the transplant sites of both cograft and adrenal medullary graft recipients than in sham grafted control animals.     

Cryopreservation,survival and function of intrastriatal fetal mesencephalic grafts in a rat model of Parkinson's disease

Summary In the present study we quantitatively assessed to what extent freeze-storage at liquid nitrogen temperature influences the survival and function of fetal mesencephalic grafts in the dopamine-depleted rat striatum. Ventral mesencephalic (VM) tissue was dissected from rat fetuses and stored overnight in a preservative medium at 4 °C (hibernation). It was grafted intrastriatally either as a fresh cell suspension or was frozen as tissue fragments or as a cell suspension after stepwise incubation in ascending concentrations of dimethyl-sulphoxide. Following a cryopreservation interval of 80 days in liquid nitrogen, the frozen samples were rapidly thawed, rinsed, and grafted. Cellular viabilities of graft cell suspensions, as assessed by ethidium bromide/acridine orange staining, were decreased from 90% in fresh tissue to 38-35% in frozen and thawed tissue. Amphetamine-induced turning behavior at 6 weeks post-grafting was significantly attenuated in hosts that had received fresh grafts or grafts that were frozen as tissue fragments. Tyrosine hydroxylase-(TH-) immunocytochemistry of recipient brains revealed significant decreases in TH-positive graft cell numbers in rats grafted with cryopreserved tissue (38–42% of fresh tissue). Moreover, the dye exclusion viability of thawed VM tissue was found to accurately predict the subsequent graft survival. There was no difference with respect to graft cell numbers between the two freezing methods employed, though block storage seems to be more simple from a practical point of view. The present study indicates that freezing in liquid nitrogen may be a feasible method for long-term storage of fetal neural tissue for grafting, although a marked decrease in graft survival and function of cryopreserved tissue must be taken into account.Present address: Dept. of Medical Physiology     

胚基底前脑原位移植与靶区移植对修复Alzheimer病鼠的影响

本文用使君子酸(quisqualic acid,QA)分两点注入Sprague-Dawley大鼠左侧基底大细胞核制成Alzheimer病动物模型。破坏1周后,一组动物将同种胚基底前脑悬液注入模型鼠的额叶和顶叶,另一组动物则将胚基底前脑悬液原点注入破坏区。移植后5个月行为测试被动回避试验及主动回避试验,与破坏后1周的测试结果相比有显著性差异(p<0.05),表明移植后行为有明显改善。但两组动物移植后行为改善的程度无明显差异。形态学观察发现两组动物移植区均有AChE阳性神经元及阳性纤维终末形成的斑片。原位移植区范围较皮质移植区略大,移植区所见AChE阳性神经元形态与正常基底大细胞核的细胞相似。实验结果表明原位移植亦能获得与靶区移植同样的效应,提示基底大细胞核区在受损后可能产生某种神经营养因子,促进了胚脑细胞的存活。Alzheimer病模型鼠机能的恢复不一定与神经网络的重建有关,而与具有产生ACh递质的内源性微泵有关。     

Comparison of mesencephalic free-floating tissue culture grafts and cell suspension grafts in the 6-hydroxydopamine-lesioned rat

Ventral mesencephalon (VM) of fetal rat and human origin grown as free-floating roller-tube (FFRT) cultures can survive subsequent grafting to the adult rat striatum. To further explore the functional efficacy of such grafts, embryonic day 13 ventral mesencephalic tissue was grafted either after 7 days in culture or directly as dissociated cell suspensions, and compared with regard to neuronal survival and ability to normalize rotational behavior in adult rats with unilateral 6-hydroxydopamine (6-OHDA) lesions. Other lesioned rats received injections of cell-free medium and served as controls. The amphetamine-induced rotational behavior of all 6-OHDA-lesioned animals was monitored at various time points from 18 days before transplantation and up to 80 days after transplantation. Tyrosine hydroxylase (TH) immunostaining of the histologically processed brains served to assess the long-term survival of grafted dopaminergic neurons and to correlate that with the behavioral effects. Additional cultures and acutely prepared explants were also fixed and stored for histological investigation in order to estimate the loss of dopaminergic neurons in culture and after transplantation. Similar behavioral improvements in terms of significant reductions in amphetamine-induced rotations were observed in rats grafted with FFRT cultures (127%) and rats grafted with cell suspensions (122%), while control animals showed no normalization of rotational behavior. At 84 days after transplantation, there were similar numbers of TH-immunoreactive (TH-ir) neurons in grafts of cultured tissue (775 ± 98, mean ± SEM) and grafts of fresh, dissociated cell suspension (806 ± 105, mean ± SEM). Cell counts in fresh explants, 7-day-old cultures, and grafted cultures revealed a 68.2% loss of TH-ir cells 7 days after explantation, with an additional 23.1% loss after grafting, leaving 8.7% of the original number of TH-ir cells in the intracerebral grafts. This is to be compared with a survival rate of 9.1% for the TH-ir cells in the cell-suspension grafts. Immunostaining for the calcium-binding proteins calretinin, calbindin, and parvalbumin showed no differences in the neuronal expression of these proteins between the two graft types. In conclusion, we found comparable dopaminergic cell survival and functional effects of tissue-culture grafts and cell-suspension grafts, which currently is the type of graft most commonly used for experimental and clinical grafting. In this sense the result is promising for the development of an effective in vitro storage of fetal nigral tissue, which at the same time would allow neuroprotective and neurotrophic treatment prior to intracerebral transplantation. Received: 11 March 1997 / Accepted: 19 August 1997     

Chronic implants of chromaffin tissue into the dopamine-denervated striatum. Effects of NGF on graft survival,fiber growth and rotational behavior

Summary Adult rat chromaffin tissue was transplanted into striatum of adult rat recipients whose nigrostriatal dopamine pathway had been lesioned on the grafted side by 6-hydroxydopamine. Long-term survival of the intrastriatal chromaffin grafts and the effects of treatment with nerve growth factor (NGF) was studied histochemically using Falck-Hillarp fluorescence histochemistry and functionally using rotational behavior induced by apomorphine. Small, cortex-free adrenal chromaffin tissue grafts survived permanently in striatum. The number of surviving cells was significantly increased by NGF. NGF treatment also caused transformation of many cells towards a more neuronal phenotype and greatly enhanced the adrenergic nerve fiber outgrowth into host brain tissue. NGF was either injected stereotaxically into the site of transplantation or infused continuously using implantable osmotic minipumps and a stereotaxically placed chronic indwelling dialysis fiber through striatum. The latter arrangement permitted continuous infusion of NGF for 14–28 days and caused a vigorous adrenergic nerve growth response by the grafts directed towards the source of NGF in the brain. There was a clearcut correlation between morphological signs of taking and rotational behavior. Grafts, and in particular grafts treated with NGF, were able to significantly and permanently counteract the rotational behavior induced by apomorphine. There seemed to be a dose relationship between NGF treatments and amount of reduction of asymmetric behavior. NGF treatment probably decreased the relative importance of diffuse release of catecholamines from chromaffin cells in the graft and increased the importance of adrenergic innervation of host striatum by cells in the graft. Immunofluorescence using antibodies against glial fibrillary acidic protein did not reveal any marked gliosis around the grafts nor were there any marked gliotic reactions around chronic indwelling dialysis fibers. We conclude that implantation of chromaffin tissue into striatum in conjunction with NGF treatments is an effective means of counteracting some of the symptoms of experimentally induced unilateral parkinsonism in rats.     

缺氧诱导因子1α基因转染脂肪干细胞与自体脂肪移植

背景：自体颗粒脂肪组织作为理想的填充材料用于美容与重建修复领域,但因其移植后组织大量被吸收,严重影响了远期效果。 目的：观察缺氧诱导因子1α基因转染脂肪干细胞对自体移植脂肪组织存活率的影响。 方法：取健康成年人吸脂术后的脂肪组织分离脂肪干细胞并行原代及传代培养,传至第3代,调整细胞浓度为1×109 L-1,经缺氧诱导因子1α基因转染后调整细胞浓度为1×1011 L-1备移植时使用;同时选用同一抽脂术后的脂肪组织颗粒并进行纯化,利用纤维蛋白胶的物理特性制备不同成分脂肪组织复合移植物,在20只裸鼠背部皮下随机分离3个腔隙,实验分为3组：基因修饰组移植经缺氧诱导因子1α基因修饰的脂肪干细胞+脂肪组织+纤维蛋白胶;基因未修饰组移植单纯脂肪干细胞+脂肪组织+纤维蛋白;生理盐水组移植生理盐水+脂肪组织+纤维蛋白。 结果与结论：移植后3个月和6个月,各组移植物血管密度比较,基因修饰组>基因未修饰组>生理盐水组,组间比较差异有显著性意义(P < 0.05);各组移植物脂肪细胞纤维坏死率比较,基因修饰组<基因未修饰组<生理盐水组,组间比较差异有显著性意义( P < 0.05);各组移植物脂肪质量保持率比较,基因修饰组>基因未修饰组>生理盐水组,组间比较差异有显著性意义(P < 0.05)。结果证实,缺氧诱导因子1α基因转染脂肪干细胞可促进移植脂肪组织局部的血管再生,促进脂肪细胞的成活,增加脂肪组织的质量保持率,减少脂肪移植术后的纤维坏死程度。     

Rathke's pouch grafts in adult brain sites

Donor tissue containing Rathke's pouch (RP) with its associated mesenchyme and neural lobe was isolated from 15-day fetal rats and stereotaxically transplanted either to hypothalamic hypophysiotropic sites or to cerebral cortex of adult females for 30 days. Hosts either were intact or had been hypophysectomized 2–4 weeks prior to transplantation of Rathke's pouch. Grafts in the hypothalamus of either intact or hypophysectomized hosts were pleomorphic and large, often as wide as 1–2 mm, and occasionally larger. Grafts in the cortex of either intact or hypophysectomized hosts were nodular and occasionally projected upward in association with the meninges (cortex/meninges grafts). Certain features were characteristic of the grafts in all experimental groups, i.e., development of histotypic pars distalis with cell cords and fenestrated capillaries. In all experimental groups gonadotrophs and somatotrophs, when present, were localized at the graft margin adjacent to the connective-tissue interface; mammotrophs, when present, were distributed throughout the graft. Features specific to each experimental group also were apparent. Grafts in the hypothalamus of both intact and hypophysectomized hosts typically were encapsulated by a labyrinthine meshwork of cell processes, whereas cortex/meninges grafts directly abutted dense connective tissue or neural tissue. In hypothalamic grafts in intact hosts, moderately differentiated mammotrophs, gonadotrophs, and somatotrophs could be identified by their cytological features and immunopositivity for prolactin, luteinizing hormone, and growth hormone, respectively. In hypothalamic grafts in hypophysectomized hosts, mammotrophs were absent, and gonadotrophs and somatotrophs were poorly granulated and not abundant. Grafts in the cortex of intact hosts contained numerous, well-differentiated mammotrophs, gonadotrophs, and somatotrophs. Many of the mammotrophs in these grafts were hypertrophied, and profiles of exocytosis were common. In grafts in the cortex of hypophysectomized hosts, mammotrophs were either absent or very few, whereas gonadotrophs and somatotrophs were numerous. Gonadotrophs in these grafts were dramatically hypertrophied, although exocytosis was rare. The results indicate that development of histotypic pars distalis may occur in hypophysiotropic and nonhypophysiotropic brain sites and that the hormonal state of the host as well as implantation site modulate cytodifferentiation of specific pars distalis cell types.