茶多酚对沙土鼠脑缺血后再灌注氧化损伤的保护作用

采用蒙古沙土鼠（Ｇｅｒｂｉｌ）制作脑缺血后再灌注模型,用化学发光法（Ｃｈｅｍｉｌｕｍｉｎｓｃｅｎｅ,ＣＬ）测定缺血后再灌注、喂饲茶多酚后脑组织内源性超氧化物歧化酶（ＳＯＤ）的活性、脂质过氧化程度（ＬＰＯ）及脑组织ＡＴＰ能量代谢的变化;运用顺磁共振法（ＥＳＲ）检测了缺血后再灌注过程中产生的活性氧（ＲｅａｃｔｉｖｅＯｘｙｇｅｎＳｐｅｃｉｅｓ,ＲＯＳ）,探讨了脑缺血后再灌注的损伤机制及抗氧化剂的保护作用。在整体模型的研究中表明,茶多酚对沙土鼠脑缺血后再灌注氧化损伤具有显著的保护作用;内源性超氧化物歧化酶活性提高,脂质过氧化程度下降,ＡＴＰ水平升高     

微生物SOD的提纯、育种及分子生物学研究

超氧化物歧化酶（ＳＯＤ）是广泛存在于生物体内的一种对机体起保护作用的金属酶,其制品在医疗、食品与化妆品等领域显示出良好的应用前景。常规制取动物ＳＯＤ受血液来源和得率的限制,而以微生物为原料制备ＳＯＤ则具有可以大规模培养的优势。本文集中介绍了有关微生物ＳＯＤ提纯、育种和分子生物学等的研究结果,并就继续研究与应用中的某些问题作了初步探讨。     

螺旋藻对小鼠SOD和GSH—Px活力的影响

采用微量测定法,观察螺旋藻对３２只昆明种小白鼠全血中超氧化物歧化酶（ＳＯＤ）和谷光甘肽过氧化物酶（ＧＳＨ－Ｐｘ）活性的影响。结果表明,灌胃螺旋藻试验组（ＳＯＤ）活性（１５７７．１６±１６９．８８ＩＵ／ｇＨｂ）,与相应对照组（１３３６．２７±１５８．２３ＩＵ／ｇＨｂ）比较,ＧＳＨ－Ｐｘ活性（２８．３３±２．３７ＩＵ／ｍｌ）与相应对照组（２４．８７±３．２６ＩＵ／ｍｌ）比较,差别均有非常显著意义（Ｐ＜０．０１）;提示螺旋藻有提高动物ＳＯＤ和ＧＳＨ－Ｐｘ活性的功效     

普通小麦细胞质雄性不育系及其保持系线粒体DNA的RAPD分析

应用随机扩增多态ＤＮＡ（ＲａｎｄｏｍａｍｐｌｉｆｉｅｄｐｏｌｙｍｏｒｐｈｉｃＤＮＡｓ,ＲＡＰＤ）技术,对普通小麦细胞质雄性不育系（Ａ）及其保持系（Ｂ）线粒体基因组（ｍｉｔｏｃｈｏｎｄｒｉａｌｇｅｎｏｍｅ）的指纹图谱进行了分析。共使用引物４１个,其中２０个引物得到了扩增产物,部分引物扩增结果表现多态性。说明线粒体ＤＮＡ（ｍｉｔｏｃｈｏｎｄｒｉａｌＤＮＡ,ｍｔＤＮＡ）序列在不育系和保持系之间存在差异,进一步明确了小麦细胞质雄性不育（ｃｙｔｏｐｌａｓｍｉｃｍａｌｅｓｔｅｒｉｌｅ,ＣＭＳ）与ｍｔＤＮＡ的关系。     

家庭内性传播疾病感染研究

为了解性传播疾病（ＳｅｘｕａｌｌｙＴｒａｎｓｍｉｔｔｅｄＤｉｓｅａｓｅｓＳＴＤ）对家庭内传播的影响,用多聚酶链反应（ＰＣＲ）等方法检测了９４对夫妻和其中１５户家庭中１６名子女的ＳＴＤ病原体ＮＧ、ＣＴ、ＵＵ、ＨＰＶ、梅毒螺旋体和白色念珠菌。结果表明：男性不洁性史为６８．１５％而女性为４．２６％,两者间有显著差异（Ｐ＜０．０１）,但其发病率无统计上显著差异（男７６．６０％、女７３．４０％）。ＳＴＤ感染以ＣＴ感染最高,达４４．６８％,ＮＧ感染为３１．９１％,ＨＰＶ感染是１５．９６％,未检出梅毒和ＨＳＶ感染。患者中两种及以上病原感染过３５．１１％。５６．２５％的子女ＳＴＤ感染系其患ＳＴＤ父母传染的。这提示如果夫妻任何一方检出有ＳＴＤ感染,另一方须做系统监测与咨询,以便及时采取治疗和预防措施并避免子女受到感染。     

三种类型辐射对质粒超螺旋DNA损伤的研究

用ａｇａｒｏｓｅ电泳和图象处理技术比较了６０Ｃｏγ射线、ＵＶ及低能Ｎ＋离子处理ｐＵＣ１９ＤＮＡ超螺旋结构的损伤效应及若干自由基清除剂的保护效应。结果表明：（１）γ射线和ＵＶ照射干燥ＤＮＡ的损伤显著低于水溶液样品;（２）Ｎ＋离子注入后超螺旋ＤＮＡ的减少（ＳＣ％）与剂量呈良好线性关系,而γ射线和ＵＶ组的ＳＣ％随剂量升高呈指数下降;（３）干燥ＤＮＡγ辐照组的Ｄ３７值为８２０Ｇｙ,ＳＣ完全消失的剂量ＬＤ为３８１４Ｇｙ,ＬＤ／Ｄ３７＝４．６５;ＵＶ照射组的相应值分别为：１．６５Ｊ／ｃｍ２,７．６５Ｊ／ｃｍ２,４．６４;Ｎ＋离子组的相应值为：３．２×１０１５Ｎ＋／ｃｍ２,５．０×１０１５Ｎ＋／ｃｍ２和１．５６。虽然上述三种辐射的剂量单位不同,不能直接比较其相对生物学效应,但从ＬＤ与Ｄ３７的比值可反映ＤＮＡＳＣ破坏的程度和终点剂量（ＳＣ％＝０）的大小。从而看出,Ｎ＋离子（高ＬＥＴ辐射）比γ射线（低ＬＥＴ辐射）ＵＶ（非电离辐射）对ＤＮＡ损伤作用更强;（４）乙醇、甘露醇等自由基清除剂对电离辐射损伤有很强的保护作用,但对ＵＶ损伤未见明显的保护效应     

精胺和Mg~（2＋）对tRNA~（Ile）圆二向色谱的影响

由于精胺（ｓｐｅｒｍｉｎｅ）能特异地刺激哺乳动物ｔＲＮＡ~（Ｉｌｅ）的氨基酰化,本文用纯化的牛肝ｔＲＮＡ~（Ｉｌｅ）观察了精胺和Ｍｇ（２＋）对ｔＲＮＡ~（Ｉｌｅ）ＣＤ光谱的影响。结果显示：Ｍｇ（２＋）可使牛肝ｔＲＮＡ~（Ｉｌｅ）ＣＤ光谱峰向短波方向偏移２ｎｍ,波峰为２６３ｎｍ,峰值被增大约１０％,ΔθＭｇ（２＋）＝２．３×１０３ｄｅｇ·ｃｍ２／ｄｍｏｌ;而精胺使牛肝ｔＲＮＡ~（Ｉｌｅ）ＣＤ光谱峰减少４０％,Δθｓｐｅｒｍｉｎｅ＝１×１０（－４）ｄｅｇ·ｃｍ２／ｄｍｏｌ;精胺和Ｍｇ（２＋）对肝ｔＲＮＡ~（Ｉｌｅ）－ＩｌｅＲＳ复合物或ＩｌｅＲＳ的ＣＤ光谱基本无影响。表明Ｍｇ（２＋）和精胺可影响牛肝ｔＲＮＡ~（Ｉｌｅ）的构象。实验同时以酵母ｔＲＮＡ（Ｐｈｅ）和Ｅ·ｃｏｌｉｔＲＮＡ~（Ｉｌｅ）作为对照。     

多胺在肿瘤研究中的意义

多胺（Ｐｏｌｙａｍｉｎｅ）是一类含二个或二个以上氨基的脂肪族化合物,它包括腐胺（Ｐｕｔｒｅｓｃｉｎｅ,Ｐｕｔ）、精脒（亚精胺）（Ｓｐｅｒｍｉｄｉｎｅ,Ｓｐｄ）、精胺（ｓｐｅｒｍｉｎｅｓｐｍ）。多胺来源于Ｌ－鸟氨酸;鸟氨酸脱羧酶（ＯｒｎｉｔｈｉｎｅＤｅｃａｒｂｏｘｙｌａｓｅ,ＯＤＣ）是多胺合成的限速酶。多胺与细胞的分裂分化、核酸代谢、蛋白质生物合成等有密切关系。细胞外液中浓度升高的多胺主要来源于肿瘤细胞。现已发现神经系统肿瘤、白血病、淋巴瘤、恶性黑色素瘤、肺癌、乳腺癌、消化系统肿瘤、泌尿生殖系统肿瘤病人体液中的多胺含量有不同程度的升高,作为恶性肿瘤辅助诊断、疗效及预后的制定,是一项较好的（临床诊断肿瘤）指标。多胺的分析方法、多胺合成抑制剂、鸟氨酸脱羧酶的调控机制及多胺与癌基因之间关系是值得进一步研究的新颖内容。     

稀土Nd~（3＋）对植物叶绿体类囊体蛋白复合物影响的研究

Ｎｄ￣（３＋）对植物叶绿体类囊体蛋白复合物的影响,不仅表现在对叶绿体类囊体膜溶液的吸收光谱改变上,而且也表现在对色素蛋白复合物ＳＤＳ－ＰＡＧＡ电泳带扫描图谱吸收峰面积变化上;同时也对ＤＣＩＰ光还原活力表现出抑制作用,对Ｃａ￣（２＋）－ＡＴＰａｓｅ的活力表现出低浓度激活,高浓度抑制的作用。     

光（温）敏核雄性不育水稻育性转换中幼穗和花药的某些生理指标变化

光（温）敏核雄性不育水稻（Ｐｈｏｔｏｐｅｒｉｏｄ／ｔｅｍｐｅｒａｔｕｒｅ－ｓｅｎｓｉｔｉｖｅｇｅｎｉｃｍａｌｅ－ｓｔｅｒｉｌｅｒｉｃｅ,简称Ｐ／ＴＧＭＲ）８９０２５和培矮６４ｓ在秋季从不育阶段经半不育阶段向可育阶段转变进程中,对其花粉母细胞形成期（Ⅴ）、花粉母细胞减数分裂期（Ⅵ）的幼穗和成熟花药（Ⅷ）中过氧化物酶（Ｐｅｒｏｘｉｄｓｅ,简称ＰＯＤ）、超氧物歧化酶（Ｓｕｐｅｒｏｘｉｄｅｄｉｓｍｕｔａｓｅ,简称ＳＯＤ）．和过氧化氢酶（Ｃａｔａｌａｓｅ,简称ＣＡＴ）活性测定表明,幼穗和花药相同发育时期的酶活性随正常花粉的比率升高而增加,但以成熟花药中增加最多．并伴有丙二醛（Ｍａｌｏｎａｌｄｅｈｙｄｅ,简称ＭＤＡ）含量减少．表明自由基代谢的变化可能与光（温）敏核雄性不育水稻花粉败育有关,且自由基代谢变化在幼穗发育中期即已开始．     

Patterns of pollen removal and deposition in Polemonium brandegeei (Polemoniaceae): the role of floral visitors,floral design and sexual interference

The arrangement, colour, shape and size of floral parts (collectively floral design) have evolved primarily to promote mating success via animal‐mediated pollen transfer. Although numerous studies have examined variation in pollinator assemblages, relatively few have examined patterns of pollen removal and deposition in the presence of fluctuating pollinators and ineffective floral visitors; therefore, net pollen removal and deposition by entire visitor assemblages are unclear. We studied the timing (diurnal or nocturnal) and effects of floral traits on pollen removal and deposition under a dynamic visitor assemblage of Polemonium brandegeei. We quantified pollen grains remaining in anthers (pollen removal) and deposited on stigmas (pollen deposition) of plants visited during either the day (07:30–20:00 h) or night (20:30–07:30 h) in natural populations over two flowering seasons. Pollen removal and deposition occurred both diurnally and nocturnally during our study. Increased diurnal removal and deposition coincided with peak floral visitations in 2006. This increase in pollen removal and deposition may reflect increased visits by pollen consumers, effective hawkmoth pollinators and increased self‐pollen deposition due to hot, dry weather. Nonlinear effects of style length significantly affected pollen removal, with less pollen remaining in flowers with intermediate style lengths. Pollen deposition was more complex, with herkogamy and anther height affecting deposition. Further, close proximity of stigmas and anthers increased the potential for sexual interference between pollen removal and deposition. Overall, flower visitations and pollen removal and deposition varied between years and populations, but sex organ placement consistently influenced the removal and deposition of pollen.     

Ectopic expression of Arabidopsis thaliana plasma membrane intrinsic protein 2 aquaporins in lily pollen increases the plasma membrane water permeability of grain but not of tube protoplasts

To investigate the role of aquaporin-mediated water transport during pollen grain germination and tube growth, Arabidopsis thaliana plasma membrane intrinsic proteins (PIPs) were expressed in pollen of Lilium longiflorum (lily). Successful expression of AtPIPs in particle-bombarded lily pollen grains was monitored by co-expression with fluorescent proteins and single-cell RT-PCR, and by measuring the water permeability coefficient (P(os)) in swelling assays using protoplasts prepared from transformed pollen grains and tubes. Expression of AtPIP1;1 and AtPIP1;2 in pollen grains resulted in P(os) values similar to those measured in nontransformed pollen grain protoplasts (6.65 +/- 2.41 microm s(-1)), whereas expression of AtPIP2 significantly increased P(os) (AtPIP2;1, 13.79 +/- 6.38; AtPIP2;2, 10.16 +/- 3.30 microm s(-1)). Transformation with combinations of AtPIP1 and AtPIP2 did not further enhance P(os). Native pollen tube protoplasts showed higher P(os) values (13.23 +/- 4.14 microm s(-1)) than pollen grain protoplasts but expression of AtPIP2;1 (18.85 +/- 7.60 microm s(-1)) did not significantly increase their P(os) values. Expression of none of the tested PIPs had any effect on pollen tube growth rates. The ectopic expression of AtPIP2s in lily pollen increased the water permeability of the plasma membrane in pollen grains, but not in pollen tubes. The measured endogenous water permeability does not limit water uptake during tube growth, but has to be regulated to prevent tube bursting.     

Germination and <Emphasis Type="Italic">In Vitro</Emphasis> Growth of Petunia Male Gametophyte Are Affected by Exogenous Hormones and Involve the Changes in the Endogenous Hormone Level

The data obtained characterize the changes in the contents of endogenous phytohormones (IAA, cytokinins, GA, and ABA) in germinating pollen grains and growing pollen tubes of a self-compatible clone of petunia (sPetunia hybrida L.) within an 8-h period under in vitro conditions. The hydration and initiation of germination of pollen grains brought the ABA content down to a zero level, while the levels of GA, IAA, and cytokinins increased 1.5–2-fold. Later, in the growing pollen tubes, the GA content increased twofold, while the levels of IAA and cytokinins decreased. The exogenous ABA and GA₃ considerably promoted pollen germination and pollen tube growth; however, only the treatment with GA₃ produced the maximum length of pollen tubes. The exogenous IAA promoted and the exogenous cytokinins hindered the growth of pollen tubes. The membrane potential, as assessed with a potential-sensitive dye diS-C₃-(5), considerably increased in the pollen grains treated with ABA and benzyladenine, whereas IAA and GA₃ did not practically affect it. The authors conclude that the mature pollen grains contain the complete set of hormones essential for pollen germination and pollen tube growth. ABA, GA, and IAA together with cytokinins control the processes of pollen grain hydration, germination, and pollen tube growth, respectively.__________Translated from Fiziologiya Rastenii, Vol. 52, No. 4, 2005, pp. 584–590.Original Russian Text Copyright © 2005 by Kovaleva, Zakharova, Minkina, Timofeeva, Andreev.     

甜柿巨大花粉萌发特征及辐射敏感性研究

以‘禅寺丸’（Diospyros kakiL.f)为试材,对巨大花粉萌发率,花粉管伸长,亲和性及辐射敏感性进行了研究。结果表明：（1）巨大花粉在培养基和柱头上正常萌发,不存在萌发及亲和性障碍;（2）巨大花粉萌发迟缓及低萌发率造成其与普通花粉受精竞争中处于劣势;（3）巨大花粉和普通花粉对^60Coγ-射线辐射敏感性有差异。巨大花粉的敏感性低于普通花粉,1200Gy为刺激巨大花粉萌发的适合剂量,同时可抑制普通花粉萌发,从而可相对提高巨大花粉的受精竞争力;（4）辐射延迟效应造成巨大花粉的萌发率在一定期间内有下降趋势。但自身的修复机制可部分恢复其生活力。     

Induction of embryogenic pollen grains in situ and subsequent in vitro pollen embryogenesis in Nicotiana tabacum by treatments of the pollen donor plants with feminizing agents

Tobacco plants ( Nicotiana tabacum L., var. Badischer Burley) were treated with chemicals (sprays and soil drenches) known to affect sex expression in other species. Their effect was tested on sex balance, pollen sterility, embryogenic pollen grain (P-grain) formation in situ, and on pollen plant formation in anther and pollen cultures after anther preculture. Napthalene acetic acid (NAA) increased the length of pistils and stamens and shifted sex balance towards femaleness when the plants were raised in long or short days at 24 or 15°C. In parallel, pollen sterility, P-grain frequency in situ and pollen plant production from anther and pollen cultures were increased by NAA. Alar 85 redueed the length of pistils and stamens and shifted sex balance towards femaleness when the plants were raised in long days at 24°C, but shifted it towards maleness in short days and/or at 15°C. In parallel, pollen sterility, P-grain frequency in situ, and pollen plant production in vitro were increased when plants in long days at 24°C were treated with Alar 85, but decreased when plants in short days and/or at 15°C were treated. Ethrel, Cycocel, and GA₃ applied in a similar manner, were ineffective. Water sprays and nitrogen starvation shifted sex balance towards femaleness in long days at 15°C and increased pollen sterility, P-grain frequency in situ and pollen plant production in vitro. At 24°C, water sprays and nitrogen starvation had no effect.     

Pollen as a source of food for egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae)

The value of corn pollen as a food source for Trichogramma brassicae Bezdenko (Hymenoptera: Trichogrammatidae) was assessed in the laboratory by testing the effect of different pollen diets on the longevity, capacity of parasitism and other life-table parameters. T. brassicae females that fed on corn pollen and water (wet filter paper dusted with pollen) lived significantly longer (4.97 days) than females that fed on water alone (2.67 days), but significantly shorter than those feeding on honey alone (8.37 days) or corn pollen and honey (8.23 days), respectively, in the absence of host eggs. The presence of European corn borer eggs (Ostrinia nubilalis Huebner, Lepidoptera: Pyralidae) significantly increased longevity. With host eggs available, female T. brassicae that fed on corn pollen and water lived significantly longer (4.9 days) than on water alone (2.60 days), but significantly shorter than on honey alone (12.33 days) or corn pollen and honey (12.17 days), respectively. The cumulative lifetime fecundity was 82.53 offspring pupae when fed on pollen and water, which was significantly higher than 61.70 for water alone but lower than feeding on honey alone (95.70) or corn pollen and honey (99.97), respectively. Compared to water alone, corn pollen and water increased the net reproduction rate (R₀), intrinsic rate of increase (r_m), and finite rate of increase (λ), and reduced the doubling time (T₂), but had no effects on the emergence rate, sex ratio, and mean generation time (T_c). In another set of experiments, 13 out of 30 females reduced the number of pollen grains offered to them. The average number of pollen grains utilized per female in this 48-h test 2.46±0.40 (mean±SE). Hence, T. brassicae used corn pollen as food that significantly increased longevity and fecundity of the tested females. Pollen and honey supplied a complete diet for T. brassicae, compared to pollen and water or water alone.     

蜂花粉抗脑衰老的实验动物研究

蜂花粉抗脑衰老的实验动物研究蒋滢,杨炳华,黄美英苏州医学院生化教研室苏州２１５００７２探索衰老机制,寻求延缓衰老的有效途径是生命科学中的重大问题,也是亟待解决的实际问题。脑是指挥全身一切活动的中枢,脑组织特别容易遭受自由基及活性氧的损伤,因此防治脑衰...     

Flavonols stimulate development, germination, and tube growth of tobacco pollen

The effect of anther-derived substances on pollen function was studied using pollen produced by in vitro culture of immature pollen of tobacco (Nicotiana tabacum L.) and petunia (Petunia hybrida). Addition of conditioned medium consisting of diffusates from in situ matured pollen strongly increased pollen germination frequency and pollen tube growth, as well as seed set after in situ pollination. Thin-layer chromatography and depletion of phenolic substances by Dowex treatment indicated that flavonols are present in the diffusate and may be the active compounds. When added to the germination medium, flavonols (quercetin, kaempferol, myricetin) but not other flavonoids strongly promoted pollen germination frequency and pollen tube growth in vitro. The best results were obtained at very low concentrations of the flavonols (0.15-1.5 μm), indicating a signaling function. The same compounds were also effective when added during pollen development in vitro.     

Mating system and the hybridization between self-compatible Phlox cuspidata and self-incompatible Phlox drummondii

Mating system can impact the frequency of hybridization and therefore the maintenance of species diversity. I evaluate the effects of weak self-incompatibility (SI) in Phlox cuspidata and SI in Phlox drummondii on mating success within species and on hybridization dynamics between species under controlled conditions. The effects of SI on hybridization frequency were assessed by manipulating the relatedness of conspecific pollen and the relative timing of pollen deposition in mixed-donor interspecific pollinations. Selfing as opposed to outcrossing increased hybridization by 16% in P. cuspidata maternal plants and by 48% in P. drummondii maternal plants because self pollen did not compete as well against heterospecific pollen. The relative timing of conspecific versus heterospecific pollen deposition also impacted hybridization. In self-compatible P. cuspidata, the deposition of self pollen 5 h earlier than heterospecific pollen decreased hybridization by 28%. In self-incompatible P. drummondii, a 5 h delay in the deposition of compatible conspecific pollen increased hybridization by 32%. In this hybrid system, early self-pollination can decrease hybridization (but increase inbreeding) by P. cuspidata maternal plants, and SI may increase hybridization by P. drummondii maternal plants.     

Effects of seasons and hormones on pre- and postfertilization barriers of crossability andin vitro hybrid development betweenVigna unguiculata andV. mungo crosses

Effect of two different seasons and hormones on pre- and postfertilization barriers in crossability were studied inVigna mungo, V. unguiculata and their crosses. Significant differences between the two seasons for pollen fall, pollen germination, tube growth and pod set were observed. In kharif season with an average temperature of 26 to 30 °C and 75 to 85 % humidity all the characters showed higher values than in the spring season with a higher temperature of 32 to 36 °C and low humidity of 40 to 50 %. Application of gibberellic acid (GA) alone and a combination of gibberellic acid, naphthaleneacetic acid (NAA) and kinetin (KIN) significantly increased the pollen fall by 7–13 %, pollen germination by 10–12 % and pollen tube growth by 27–30 %. More pollen tube abnormalities in interspecific crosses only indicates partly incompatible reaction of pollen tube in the stylar tisue. Hormonal treatments, especially GA, significantly increased the pod set and pod harvest by 20 % and 34 %, respectively. Higher pod harvest was seen in crosses withV. unguiculata as female parent. GA treatment enhanced pollen germination and pollen tube growth, and by partially overcoming embryo abortion for 10 to 12 d, immature embryos were successfully rescued forin vitro production of hybrid plantlets.