蔓性千斤拔组织培养中种子灭菌和芽增殖的研究

[目的]研究蔓性千斤拔组织培养中种子灭菌的方法,筛选适宜芽增殖的外植体及激素组合。[方法]用乙醇、次氯酸钠和升汞的不同组合对种子进行灭菌,然后比较顶芽和带腋芽的茎段作为外植体进行继代增殖的效果,探讨不同激素组合对芽增殖的影响。[结果]较好的种子灭菌方法为:75%乙醇30 s+10%NaClO10 min+0.1%HgCl25 min;带腋芽的茎段为较好的继代增殖外植体。6-BA对芽增殖有显著促进作用;KT对芽的增殖效果不如6-BA;芽增殖的最佳激素组合为6-BA2.0 mg/L+IAA0.1 mg/L,增殖倍数为6.74。[结论]获得了较好的种子灭菌方法,筛选出适合继代增殖培养的外植体和激素组合,为蔓性千斤拔组织培养的深入研究提供实验基础。     

Quantitative analysis of pattern of gonial proliferation during sexual maturation in Japanese scallop <Emphasis Type="Italic">Patinopecten yessoensis</Emphasis>

ABSTRACT:   This study was undertaken to describe and quantitatively analyze the pattern of development of gametes in the Japanese scallop Patinopecten yessoensis . Incorporation of 5-bromo-2'-deoxyuridine (BrdU) into gonial cells was used to quantitatively detect mitotically active gonial cells. Oogonia increased in number from November to December and decreased rapidly to March. A small number of oocytes was detected in November. Oocytes steadily increased in number and size up to March. The number of spermatogonia slightly increased from November to December, and increased markedly from January to March. Both ratios of BrdU-immunopositive gonial cells in the ovary and testis to gonial cells moderately increased from September to December. The ratio of BrdU-immunopositive spermatogonia to gonial cells drastically increased from January to February and kept an elevated level in March, whereas the oogonia started to disappear in January. The results suggest that the pattern of proliferation of gonial cells can be divided into two phases: (i) phase I, oogonia and spermatogonia slowly proliferate through the growing stage; and (ii) phase II, oogonia develop into oocytes and spermatogonia begin to proliferate rapidly through the mature and spawning stages. The proliferation of gonial cells is likely under different endocrine controls in phases I and II.     

Direct somatic embryogenesis in Epipactis veratrifolia,a temperate terrestrial orchid

Most temperate terrestrial orchids are endangered species. Attempts to produce plantlets from plants of the genus Epipactis by asexual methods have totally failed. This study was conducted using somatic embryogenesis as a rapid vegetative propagation technique for conservation of E. veratrifolia. For these purposes, effects of different types of plant growth regulators (PGRs), different types of explants, light and dark conditions, and the effect of gibberellic acid (GA₃) and Paclobutrazol (PBZ) were investigated on somatic embryogenesis induction. Abscisic acid (ABA) pre-treatment effectiveness on inducting somatic embryogenesis and increasing the number of embryos per explant were investigated. Subsequently, 16 media were tested to find the best medium for plant regeneration and shoot and root proliferation. BA (3 mg L^?1) resulted in a better response than the other PGRs by supporting the development of 17 embryos per protocorm. PBZ, which resulted in 11 embryos per explant, was better than GA₃. FAST medium supplemented with organic substances was recognized as the best medium for plant regeneration and shoot and root proliferation. ABA pre-treatment had positive effect on somatic embryogenesis initiation. This study, for the first time, succeeded in finding a rapid and suitable protocol for propagation and genetic resource conservation of E. veratrifolia.     

SNAT2介导蛋氨酸对牛乳腺上皮细胞增殖与自噬的调节作用

钠离子依赖性中性氨基酸转运体2（SNAT2）是一种氨基酸转运蛋白,可转运中性氨基酸,广泛分布于多种细胞中。氨基酸既可作为蛋白质合成的底物,也是调节细胞新陈代谢的关键信号分子,但SNAT2是否介导氨基酸调节BMECs增殖和自噬尚未见报道。本研究利用CASY细胞计数和Western blotting技术检测SNAT2过表达和siRNA干扰后牛乳腺上皮细胞（BMECs）增殖情况以及SNAT2对自噬标志蛋白LC3-Ⅰ/Ⅱ表达量的影响,并利用免疫荧光检测细胞自噬斑点（LC3-Ⅱ）变化。结果显示,SNAT2过表达时,p-PI3K、p-mTOR和Cyclin D1表达量增加,反之,p-PI3K、p-mTOR和Cyclin D1表达量下降。SNAT2抑制时,LC3-Ⅱ表达量增加,免疫荧光检测自噬斑点增多。添加自噬增强剂海藻糖（trehalose,Tre）和蛋氨酸（methionine,Met）后,与单一添加Tre组相比,Met+Tre组p-mTOR表达量增加,LC3-Ⅱ表达量降低,胞浆内绿色自噬斑点减少;添加Tre和Met并抑制SNAT2时,p-mTOR表达量下降,LC3-Ⅱ表达量增多,胞浆内绿色自噬斑点增加。以上结果表明,SNAT2可介导Met通过调控PI3K-mTOR/Cyclin D1信号通路调节BMECs的增殖与自噬。     

雏鸡感染巨型艾美耳球虫后细胞免疫的研究

通过用地塞米松处理鸡和用特异性抗原刺激因子的微量全淋巴细胞转化试验（ＬＰＡ）,研究雏鸡抗Ｅｉｍｅｒｉａｍａｘｉｍａ再感染中细胞免疫现象。结果表明,地塞米松处理可损伤鸡抗Ｅ．ｍａｘｉｍａ再感染的免疫力,这提示了ＣＤ８＋Ｔ细胞,γ－ＩＦＮ及ＩＬ－２等在抗．Ｅｍａｘｉｍａ再感染中的作用,利用Ｅ．ｍａｘｉｍａ卵囊抗原作刺激因子的微量全血ＬＰＡ结果表明,其刺激指数值与鸡抗Ｅ．ｍａｉｘｉｍａ再感染抵抗力有关。     

甲状腺素对猪小肠上皮细胞miR-let-7a基因表达及细胞增殖的影响

miR-let-7a在动物细胞的分化、增殖与凋亡等方面发挥越来越重要的作用。甲状腺激素(TH)作用非常广泛,机体的每个细胞几乎都是TH作用的靶细胞,其可以促进组织分化、生长和成熟。本实验用甲状腺素(T4)浓度分别为(0、0.02、0.03、0.05、0.075、0.1、0.2μmol/L)在体外培养猪的小肠上皮细胞。结果表明:T4处理组的细胞体积形态相对于空白对照组没有明显变化;当T4添加浓度为0.03μmol/L时,细胞的增殖率显著低于其他组(P0.05);当T4浓度为0~0.03μmol/L时,let-7a的表达随着添加剂量的增加而升高,浓度从0.03~0.2μmol/L变化时,let-7a的表达呈现降低趋势,浓度为0.03μmol/L时表达量极显著高于其他组(P0.01)。let-7a的表达量与细胞增殖呈负相关。     

Effects of IL-32γ on proliferation and cell cycle of rat vascular smooth muscle cells

AIM: To observe the effects of interleukin-32γ (IL-32γ)on the proliferation and cell cycle of rat vascular smooth muscle cells (VSMCs). METHODS: The VSMCs were isolated from the thoracic aorta of SD rats by the method of tissue-piece inoculation. The cells were cultured and treated with different concentrations of IL-32γ. The proliferation of the cells was examined by MTT assay. The cell cycles were analyzed by flow cytometry. The protein levels of NF-κB p65 and cyclin D1 were detected by Western blotting. The expression of proliferating cell nuclear antigen (PCNA)was examined by immunocytochemical staining. RESULTS: Administration of IL-32γ at the concentrations of 10~50 μg/L for 24~48 h significantly promoted the proliferation of VSMCs in a dose- and time-dependent manner. After stimulation with IL-32γ at the concentration of 50 μg/L for 24 h, the cell cycle transition from G₁ phase to S/G₂ phase was accelerated and the expression levels of NF-κB p65, cyclin D1 and PCNA increased as compared with those in control group. CONCLUSION: IL-32γ promotes the proliferation of rat VSMCs and accelerates the cell cycle transition via upregulating the expression of NF-κB p65 and cyclin D1.     

石海椒愈伤组织诱导与增殖研究

对石海椒幼嫩叶片和茎段进行了愈伤组织的诱导增殖研究,以期探寻其诱导和增殖的最佳条件。结果表明:石海椒的叶片和茎段都能诱导出愈伤组织,但最佳外植体为叶片,叶片和茎段在0.1%升汞中适合消毒时间为6 min和10 min。叶片最适诱导培养基为B5+0.6 mg/L6-BA+2.0 mg/L NAA,增殖培养基为B5+0.6 mg/L 6-BA+1.25 mg/L NAA。基本培养基和生长调节剂对愈伤诱导的影响是NAA>6-BA>基本培养基。     

德国鸢尾新品种"魂断蓝桥"离体快繁的研究

以"魂断蓝桥"的花葶为外植体进行不定芽的诱导和继代增殖的研究。结果表明:将花葶分节点接种在MS+BA 3.0 mg/L+NAA 1.0 mg/L中,其不定芽的分化率最高;在继代增殖过程中,把带芽量为4~5个的外植体接种在MS+BA 2.0 mg/L+NAA 1.0 mg/L中,继代周期为30 d,其增殖系数达到最大。     

Inhibitory effect of 1,25-(OH)2D3 on proliferation of airway smooth muscle cells from passively-sensitized patients

AIM: To investigate the effects of 1,25-dihydroxyvitamin D₃ on the proliferation of passively-sensitized human airway smooth muscle cells (HASMCs), and to explore its potential role in asthmatic airway remodeling.METHODS: HASMCs were passively sensitized with 10% serum from asthmatic patients.1,25-(OH)₂D₃ was used as the interventor.The effect of 1,25-(OH)₂D₃ on the cell proliferation and its optimal concentration were determined by MTT colorimetric assay.The cell cycle analysis was performed by flow cytometry.The expression of proliferating cell nuclear antigen (PCNA) was measured by the method of immunocytochemical staining.RESULTS: 1,25-(OH)₂D₃ at the concentrations of 10^-9-10^-7 mol/L markedly inhibited the cell proliferation and the maximum effect was observed at the concentration of 10^-7 mol/L.This concentration of 1,25-(OH)₂D₃ markedly suppressed the PCNA-positive rate and hampered the G₁/S transition in HASMCs passively-sensitized by asthmatic serum.CONCLUSION: 1,25-(OH)₂D₃ has direct inhibitory effects on the proliferation of passively-sensitized HASMCs in vitro, which may be concerned with the beneficial role of 1,25-(OH)₂D₃ on the prevention and therapy of asthmatic airway remodeling.