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91.
Giuseppe Barraco Isabelle Sylvestre Giovanni Iapichino Florent Engelmann 《Scientia Horticulturae》2011
In this study in vitro shoot tips of a Sicilian genotype of Limonium serotinum were successfully cryopreserved using the droplet-vitrification technique. Growth recovery of cryopreserved shoot tips was possible only when samples were pretreated for 16 h in liquid medium with 0.3 M sucrose, then for 5 h in liquid medium with 0.7 M sucrose before performing the cryopreservation protocol. Optimal conditions included treatment for 20 min in a loading solution containing 1.9 M glycerol + 0.5 M sucrose, treatment with vitrification solution B5 (glycerol 40.0%, sucrose 40.0%, w/v) for 60 and 90 min or vitrification solution A9 (glycerol 30.0%, dimethylsulfoxide 20.0%, ethylene glycol 20.0%, sucrose 15.0%) for 20 min, rapid cooling in minute droplets of vitrification solution, rapid rewarming by immersion for 20 min in unloading solution containing 1.2 M sucrose. Under these conditions, 37% recovery of cryopreserved shoot tips was achieved. Regrowth of cryopreserved samples was slow but always direct, without callus formation. 相似文献
92.
Takayuki ISHIKAWA Toshihiko KYOYA Yusuke NAKAMURA Eimei SATO Tatsuhiro TOMIYAMA Koichi KYONO 《The Journal of reproduction and development》2014,60(6):460-467
The study of human ovarian tissue transplantation and cryopreservation has advanced significantly. Autotransplantation of human pre-antral follicles isolated from cryopreserved cortical tissue is a promising option for the preservation of fertility in young cancer patients. The purpose of the present study was to reveal the effect of vitrification after low-temperature transportation of human pre-antral follicles by using the oxygen consumption rate (OCR). Cortical tissues from 9 ovaries of female-to-male transsexuals were vitrified after transportation (6 or 18 h). The follicles were enzymatically isolated from nonvitrified tissue (group I, 18 h of transportation), vitrified-warmed tissue (group II, 6 and 18 h of transportation) and vitrified-warmed tissue that had been incubated for 24 h (group III, 6 and 18 h of transportation). OCR measurement and the LIVE/DEAD viability assay were performed. Despite the ischemic condition, the isolated pre-antral follicles in group
I consumed oxygen, and the mean OCRs increased with developmental stage. Neither the transportation time nor patient age seemed to affect the OCR in this group. Meanwhile, the mean OCR was significantly lower (P < 0.05) in group II but was comparable to that of group I after 24 h of incubation. The integrity of vitrified-warmed primordial and primary follicles was clearly corroborated by the LIVE/DEAD viability assay. These results demonstrate that the OCR can be used to directly estimate the effect of vitrification on the viability of primordial and primary follicles and to select the viable primordial and primary follicles from vitrified-warmed follicles. 相似文献
93.
Delgado M. VALDEZ JR . Ryoma TSUCHIYA Shinsuke SEKI Naoya SAIDA Saori NIIMI Chihiro KOSHIMOTO Kazutsugu MATSUKAWA Magosaburo KASAI Keisuke EDASHIGE 《The Journal of reproduction and development》2013,59(2):205-213
Fish oocytes have not been cryopreserved successfully, probably because it is difficult
to prevent intracellular ice from forming. Previously, we have shown in medaka that
immature oocytes are more suitable for cryopreservation than mature oocytes or embryos, in
terms of permeability. We have also shown in immature medaka oocytes that the exogenous
expression of aquaporin 3 (AQP3), a water/cryoprotectant channel, promotes the movement of
water and cryoprotectants through the plasma membrane. In the present study, we attempted
to cryopreserve immature medaka oocytes expressing AQP3. We first examined effects of
hypertonic stress and the chemical toxicity of cryoprotectants on the survival of the
AQP3-expressing oocytes. Exposure to hypertonic solutions containing sucrose decreased the
survival of oocytes, but the expression of AQP3 did not affect sensitivity to hypertonic
stress. Also, AQP3 expression did not markedly increase sensitivity to the toxicity of
cryoprotectants. Of the four cryoprotectants tested, propylene glycol was the least toxic.
Using a propylene glycol-based solution, therefore, we tried to cryopreserve immature
oocytes by vitrification. During cooling with liquid nitrogen, all intact oocytes became
opaque, but many AQP3-expressing oocytes remained transparent. This indicates that the
expression of AQP3 is effective in preventing intracellular ice from forming during
cooling. During warming, however, all the AQP3-expressing oocytes became opaque,
indicating that intracellular ice formed. Therefore, the dehydration and permeation by
propylene glycol were still insufficient. Further studies are necessary to realize the
cryopreservation of fish oocytes. 相似文献
94.
95.
利用解剖学方法,对东方百合试管正常苗和玻璃苗叶片解剖结构进行了观察比较,结果表明:二类苗叶都为等面叶,其表皮均由单层细胞构成,气孔突出,且叶肉中通气组织发达.与试管正常苗相比,玻璃苗的叶片厚;叶肉组织无细胞的分化;气孔突出明显,表皮细胞、叶肉细胞体积膨大;有的叶肉细胞壁发育不全,在某些区域出现空洞,壁的形态呈现不完整的现象;玻璃苗叶片的维管组织呈现退化的现象. 相似文献
96.
番木瓜茎尖超低温保存过程中的细胞超微结构 总被引:12,自引:1,他引:12
采用透射电子显微镜对番木瓜(Carica papaya L. ) 茎尖超低温保存过程中细胞超微结构变化进行观察。结果表明: 细胞在经过预培养、60% PVS2 预处理和PVS2 脱水处理, 细胞质壁分离程度逐渐加重,细胞的抗冻力增加。细胞严重伤害主要发生在液氮保存的降温及解冻的过程中, 一部分细胞的细胞壁、细胞膜以及细胞核膜均有不可逆的损伤, 可能是导致部分细胞致死的原因之一。也有部分细胞结构完整, 虽然细胞结构发生了变化, 但是程度不深, 是可逆的伤害, 在恢复培养3 d时可自动修复, 然后再生出植株。 相似文献
97.
98.
玻璃化液对鲢鱼胚胎成活的影响 总被引:3,自引:0,他引:3
本文通过5种不同抗冻剂,55组不同浓度组合,筛选出11组冷冻时能形成玻璃化最低浓度的抗冻剂和10组解冻时能形成玻璃化的抗冻剂。并对11组玻璃化液在低温下的一些物理特性进行了测定。不同组合的玻璃化液其冰点和融点各不相同,最高冰点在-19.5℃,最低达-39℃。融点最高-40℃,最低-90℃。鳝鱼胚胎在5-e中心跳时间最长达30分钟,在10-c、5-e中换17号解冻液后存活最多,达89.0%以上。 相似文献
99.
菘蓝试管苗玻璃化过程中抗氧化物酶活性的变化 总被引:3,自引:0,他引:3
为明确植物体内抗氧化酶活性变化与组培玻璃苗发生的关系,以菘蓝(Isatis indigotica Fort.)正常试管苗和玻璃苗为研究材料,对其抗氧化物酶活性和膜脂质过氧化水平进行了比较分析.结果表明:正常苗和玻璃苗中过氧化物酶(POD)活性随培养时间的延长先降低后升高,过氧化氢酶(CAT)活性先升高后降低,过氧化物歧化酶(SoD)活性和丙二醛(MDA)含量始终呈上升趋势.同一培养时期,玻璃苗中CAT、SOD活性均低于正常苗,而MDA水平远远高于正常苗.表明组培过程中有氧自由基的胁迫,而玻璃苗细胞内保护酶的调节功能紊乱,从而发生了更严重的脂质过氧化.此外,与正常苗相比,玻璃苗中POD同工酶电泳谱带出现增加、缺失等异常现象,表明玻璃苗中酶的表达失常,遗传稳定性改变. 相似文献
100.
新疆杨组织培养技术 总被引:6,自引:0,他引:6
以新疆杨(Populus alba L.vat.pyramidalis Bge.)叶片和腋芽为外植体,对适合植株再生的培养基、激素配比和培养条件进行了研究。结果表明:对于叶片,添加0.05ms/LTDZ、0.03mg/L IBA的1/2MS培养基诱导出的愈伤组织容易分化成茎丛,愈伤组织转接到含0.5mg/L BA、0.05mg/L NAA的1/2MS培养基内产生大量的丛生芽。腋芽诱导茎丛的培养基为1/2MS BA1.0mg/L NAA1.0mg/L。不定芽在IBA0.03mg/L 1/2MS的培养基内可诱导产生大量的根,生根试管苗驯化、移栽后成活率可达91%。对实验过程中的玻璃化问题进行了系统实验,发现大量元素中NH4^ 浓度过高和多次继代是引起玻璃化的主要原因,并提出了3点防止措施。 相似文献