转mtlD/gutD双价基因稻米对大鼠的毒性试验

对转mtlD/gutD双价基因稻米进行了大鼠急性、亚急性毒性实验,致突变试验和30 d喂养试验。结果表明,大鼠经口LD50＞30 g/kg体质量,无致突变作用;30 d喂养试验中,18、36、54 g/kg体质量各剂量组大鼠发育、增重、食物利用率、血常规、脏体比及病理组织学观察等各项指标与基础对照组相比均无显著差异。初步表明转mtlD/gutD双价基因稻米对大鼠来说是安全的。     

转反义PEP基因油菜超油1号菜籽油毒理性评价

为评价转反义PEP基因油菜超油1号菜籽油的食用安全性,对该样品进行了急性毒性试验和致突变试验.结果表明,转反义PEP基因超高油油菜菜籽油属无毒级,无致突变作用.大鼠90d喂养试验结果显示,各试验组大鼠体重、进食量、食物利用率、血常规、脏体比及病理组织学观察等各项指标与阴性对照均无显著性差异,无作用剂量为10.0ml/kg体重.     

转基因与常规杂交相结合改良水稻耐盐性

通过农杆菌介导法和基因枪法将CMO、BADH、mtlD、gutD和SAMDC基因以单价或双价的形式导入水稻常规品种中,再结合常规杂交育种,选育5价强耐盐性的转基因水稻植株。1~5价9类组合的水稻品系,经PCR分子检测,在转基因后代中多价目的基因聚合,遗传稳定,且分子检测与田间耐盐性的表现一致。转基因植株在盐碱地中能正常生长,拓展了水稻常规品种耐盐性。并已获得耐0.5%~1.0%NaCl的T秀水11——品3、品6和品7等9份优良株系或中间材料。     

1-磷酸甘露醇脱氢酶基因转化水稻的研究

摘要：PCR和Southern blotting检测表明,来自大肠杆菌的[i]mtlD[/i]基因已通过农杆菌介导整合进水稻基因组。[i]mtlD[/i]基因在T1代出现分离, T2代出现纯系。在0.75% NaCl胁迫下,7个转基因T3代株系都能检测到mtlD酶活性,与对照相比细胞膜的相对电导率和大分子渗漏值明显降低。部分转基因株系能在 1.0% NaCl浓度下正常生长,而对照在0.5% NaCl浓度下已不能存活。通过有性杂交途径实现了[i]mtlD[/i]和[i]gutD[/i]两个基因的聚合,部分杂交后代株系能在1.25%NaCl胁迫下正常生长结实。     

长生牌鹿茸片抗疲劳及大鼠30天喂养试验研究

为检测长生牌鹿茸片的抗疲劳功能及安全性,通过大鼠30天喂养试验观察和小鼠负重游泳试验,确定长生牌鹿茸片对大鼠各项指标的影响,及其短期毒性作用及抗疲劳功能。试验选用SPF级Wistar大鼠,雌雄各40只,随机分为低、中、高剂量组及对照组,每组雌雄各10只,连续喂养30天后对大鼠各项指标进行检测观察。选用SPF级ICR雄性小鼠40只,末次给予受试物30 min后,置小鼠在游泳箱中游泳,记录小鼠自游泳开始至死亡时间。结果表明30天喂养试验对照组及各剂量组大鼠的生长发育良好、无死亡,未观察到任何异常;体重增长、食物利用率、血常规、血生化等指标及脏体比均在正常范围内,无显著性差异(P0.05);高剂量组大鼠肝、肾、脾、睾丸、卵巢未见病理改变。小鼠负重游泳试验表明长生牌鹿茸片能延长小鼠负重游泳时间而对小鼠增重无影响。综上所述,在本实验条件下,长生牌鹿茸片对大鼠30天喂养无短期毒副作用且具有抗疲劳功能。     

杂交香稻的香味遗传模式及育种研究

 以川香28A和川香84A与无香味的恢复系CDR22、成恢177等杂交,研究F₁和F₂单粒稻米的香味遗传特点。结果表明F₁稻米无香味,恢复系的无香味表现胚乳直感现象;杂种稻米(F₂)无香味∶有香味符合15∶1的遗传分离比。川香28A与香稻恢复系636杂交,F₁和杂种稻米(F₂)的每粒米都有香味。结合过去的有关研究,提出杂交香稻香味遗传的双基因模式。介绍了运用香稻亲本转育香味基因,选育香稻保持系、恢复系和杂交香稻的育种方法和进展。     

转基因烟草生产生物可降解塑料(PHA)遗传稳定性的初步分析

为检测转只pseudoalkaligenese YS1的PHA合成酶phaC1、phaC2双价基因在转基因烟草后代植株的遗传稳定性，以已获得的两株转PHA合成酶phaC1、phaC2双价基因的烟草及其后代为材料，通过对转基因烟草各后代进行PCR、PCR-Southern检测，初步确定了P.pseudoalkaligenese YS1 PHA合成酶phaC1、vhaC2双价基因能在转基因植株的后代中稳定地遗传；利用卡那霉素抗性大田直接筛选、Southern blot等方法对阳性植株作了进一步检测。用氯仿-次氯酸钠对74株PCR-Southern检测为阳性的转化植株中进行PHAs抽提，有61株中得到目的产物。所转化的烟草在产物合成水平上转化率为67．7％。     

转Bar基因抗除草剂稻谷喂养小鼠的食用安全性评价

以转Bar基因抗除草剂水稻品种Bar 68 -1及其受体品种D68(CK)为材料,将其稻谷配制饲料后饲喂体重在18～24 g的SPF级昆明小鼠,喂养90 d后分别检测小鼠腿肌、肝脏、肾脏、脾脏、小肠中是否含有Bar基因片段及其表达蛋白磷丝菌素乙酰转移酶(PAT),同时检测了小鼠消化道内外源蛋白的消化降解和小肠线粒体基因组(mtDNA)的突变情况.结果表明:饲喂转Bar基因稻谷的实验组小鼠各脏器组织中没有检测到Bar基因片段和其表达的PAT蛋白;外源蛋白PAT在小鼠胃肠道内无耐受性,能够被机体完全消化;小鼠小肠mtDNA的测序结果无异常,没有发现突变位点.说明转基因成分没有在小鼠体内残留或发生转移,也没有导致小鼠肠道基因突变.     

转抗病基因棉花的培育研究初报

目前,我国棉花主产区相当一部分为重茬地,棉花黄萎病不断蔓延和增长,对棉花生产造成了很大的威胁,部分重病棉田因病产量损失严重,纤维品质下降,经济损失大,直接制约农村经济的发展和农民的收入。如何解决抗病性,成了棉花基因工程研究的新课题。1材料来源采用基因工程技术获得β-1,3-葡聚糖酶及几丁质酶基因双价植物表达栽体GO、GCE转化棉株。在田间对转化植株进行卡那霉素抗性检测及多代抗病性筛选,获得性状优良的抗病转基因棉花品系材料15个。2结果与分析2.1转抗病基因材料病圃抗病性检测。2003、2004年将田间选育的纯合转抗病基因棉花品…     

Wx与ALK主要等位基因不同组合对稻米品质的影响

【目的】稻米蒸煮和食味品质主要受Wx和ALK两个主效基因的调控。这两个基因在栽培稻中存在多个复等位变异,本研究旨在明确Wx和ALK基因的主要等位变异及其组合对稻米品质的影响。【方法】将Wx的3个主要等位基因(Wx^a、Wx^b和wx)与ALK的2个主要等位基因(ALK^a和ALK^c)进行不同的组合,在粳稻品种日本晴(Nip)背景下创建6个含有Wx和ALK基因不同等位变异组合的近等基因系。通过测定近等基因系的稻米理化品质明确不同等位基因及其组合对稻米品质的效应。【结果】在相同的ALK基因型背景下,含Wx^a等位基因稻米的糊化温度极显著低于wx型和Wxb型的近等基因系。稻米黏滞性受Wx和ALK等位基因组合影响较大,Wx等位变异主要影响稻米的峰值黏度、峰值时间和冷胶黏度;在相同Wx背景下,ALK等位基因主要影响稻米RVA谱的起浆温度,对稻米崩解值和消减值的影响不显著。总体来看,Nip-Wx^a/ALK^a和Nip-Wx^a/ALK^c型稻米具有较高直链淀粉含量和崩解值,较低的胶稠度,因而食味值较差;Nip-wx/ALK^a和Nip-Wx^b/ALK^a型水稻具有适中的直链淀粉含量、较软的胶稠度以及较低的糊化温度,因此这两个近等基因系热饭和冷饭的食味值较好;虽然Nip-Wx^b/ALK^c的糊化温度较高,但因其适中的直链淀粉含量和较高的胶稠度,其冷饭食味值降幅较小;Nip-wx/ALK^c稻米的热饭食味值与Nip-wx/ALK^a、Nip-Wx^b/ALK^a和Nip-Wx^b/ALK^c无差异,但因其较高的糊化温度,其冷饭食味值显著下降。【结论】Wx基因变异主要影响稻米直链淀粉含量和胶稠度,对糊化温度有一定的影响;ALK基因变异主要影响糊化温度,对直链淀粉含量无显著影响,对胶稠度存在微效影响。     

海南普通野生稻的花粉育性观察及杂交亲和性

对海南3个不同居群的普通野生稻(O.rufipogon Griff.)的花粉育性进行了观察研究,并采用荧光显微镜技术观察了转基因水稻花粉在不同居群的普通野生稻柱头上的萌发和在花柱内的生长过程。结果表明,以转基因水稻为对照,3个不同居群的野生稻相互之间花粉可育率在1%水平上差异极显著。用荧光显微镜观察时发现,转基因水稻花粉能在3个居群的普通野生稻的柱头上萌发并能到达胚珠,二者杂交亲和,同时发现,花粉管进入三亚居群胚珠的数目比儋州、万宁居群的数目多,说明相对于儋州、万宁居群来说,三亚居群与转基因水稻的杂交亲和性更高。     

Comparative study of the effects of gentamicin, neomycin, streptomycin and ofloxacin antibiotics on sperm parameters and testis apoptosis in rats

The aim of this study was to investigate the comparative effects of aminoglycosides and fluoroquinolones on testis apoptosis and sperm parameters in rats. Fifty male Wistar rats were randomly divided into control (n = 10) and experimental (n = 40) groups. The experimental groups subdivided into four groups often. Each received 5 mg kg(-1) (IP) gentamicin, 50 mg kg(-1) (IP) neomycin, 40 mg kg(-1) (IP) streptomycin and 72 mg kg(-1) (IP) ofloxacin daily for 14 days, respectively; however, the control group just received vehicle (IP). In the fourteenth day, rats were killed and sperm analyzed for sperm parameters. Testis tissues were also prepared for TUNEL assay for detection of apoptosis. There was a significant decrease in sperm count, viability and motility in all of experimental groups when compared with control group. Although in streptomycin group these parameters were less decreased than in the other experimental groups. The apoptotic cells were significantly increased in all experimental groups when compared with those seen in the controlled group. Gentamicin, neomycin and streptomycin and ofloxacin have negative effects on sperm parameters and testis apoptosis in rats. However, these side effects are less seen in the streptomycin group. Therefore, it is recommended that usage of this drug have fewer side effects on male fertility.     

利用卡氏白和尼罗红染色观察稻瘟病菌有性世代的结构

稻瘟病菌(Magnaporthe oryzae)是异宗配合的子囊菌,但至目前,关于其有性世代产生过程和结构的研究相对较少。本研究利用两个稻瘟病菌菌株Guy-11与2539在多种培养基上进行杂交试验,观察有性世代产生情况。结果表明,两菌株在所有参试培养基上杂交后均能产生子囊壳,但子囊壳的数量、产生速度和成熟度各不相同,以燕麦培养基为最佳。为了进一步观察有性世代的结构,我们采用卡氏白和尼罗红对子囊和子囊孢子进行染色和荧光观察。荧光显微镜下,子囊和子囊孢子的细胞壁均能被卡氏白染成清晰的亮蓝色,细胞结构清晰可辨。成熟的子囊壳内可产生大量的子囊,子囊中含有8个子囊孢子,子囊孢子通常含有4个细胞。同时,子囊孢子能够被尼罗红染成橘红色,表明子囊孢子中储藏大量的脂肪类物质。本研究提供了一种有效的观察稻瘟病菌有性世代结构的荧光染色方法,为后续的研究奠定了基础。     

Effect of high protein rice on nitrogen retention and growth of preschool children on a rice-based diet

The effect of high protein milled rices (IR480-5-9 and IR2153-338-3, 10% protein) on the nitrogen retention and growth of preschool Indian children was assessed in two feeding trials in a residential home. The children were offered, ad libitum, a rice-based diet in four meals daily without vitamin and mineral supplement. The children in the experimental group were given the high protein rice; those in the control group were given a local rice (7% protein). The groups had similar percent apparent digestibility and retention of dietary nitrogen. Statistically significant differences in increase in height and weight between the two groups were not consistently observed at the end of 4.5 to 5 months or 1 year. Possible factors contributing to these results are discussed.     

The effect of Rosa damascena essential oil on the amygdala electrical kindling seizures in rat

We investigated the effect of Rosa damascena Mill, essential oil on the development of induced amygdala kindling seizures. Male Wistar rats were implanted with one tripolar and two monopolar electrodes in right basolateral amygdala and dura surface, respectively. The control group was injected solvent of essential oil and two experimental groups were injected 750 and 1000 mg kg(-1) of essential oil (ip), 30 min before a daily kindling stimulation. The number of stimulations required for the first appearance of seizure stages was significantly larger in two experimental groups than in control group. Mean after discharge duration was significantly different and essential oil reduced the increase of after discharge duration. Mean after discharge amplitude was also shorter in the groups treated with essential oil than in control group. Duration time for 5th stage of seizure at fully-kindled rats was significantly shorter in two experimental groups than control group. These results suggest that Rosa damascena essential oil significantly retarded the development of seizure stages and possesses the ability to counteract kindling acquisition. The flavonoids of Rosa damascena may act via GABAA receptors as previous studies have proposed for flavonoids of other medicinal plants. More detailed studies are recommended to define the effective component(s) of Rosa on different types of epilepsy.     

Morphological changes of rabbit lacrimal gland cells from amiodarone administration

Background: Amiodarone is a drug that is used for treatment of cardiac arrhythmia after cardiac ischemia. This drug as beta blocker decreases arrhythmia rate but it has many side effects on different tissues. Since there are rare reports about changes of lacrimal glands, this research has been carried out to study the morphological and ultrastructural changes of lacrimal gland cells after amiodarone administration. Methods: Male rabbits (n = 14) were divided into control and experimental groups. Experimental group were intra peritoneally injected with a daily single dose of 80 mg/kg amiodarone for two weeks. The control group only received normal saline. At the end of the injection period, the two groups were anesthetized and perfused with Karnovsky's fixative. The lacrimal glands were removed, fixed and then prepared for light and electron microscopic studies. Quantitative studies on lacrimal gland cell micrographs were performed by point counting method. The results were statistically compared between the two groups. Results: Light microscopic observation showed many secretory granules in the cytoplasm of the lacrimal gland cells, which were also seen in the lumen of acini. Ultrastructure study of these cells showed the presence of inclusions in their cytoplasm with homogenous and dense structure. In quantitative analysis, the volume fractions (Vv) of mitochondria and nucleus to the cell showed no differences between the two groups but the Vv of euchromatin to the nucleus was different (P<0.05 ). Conclusion: The presented results show adverse effects of amiodarone on rabbit lacrimal gland cells.     

Antioxidant Role of Oleuropein on Midbrain and Dopaminergic Neurons of Substantia Nigra in Aged Rats

Background: Oleuropein is a phenolic compound which is present in the olive leaf extract. The purpose of the present study was to investigate the neuroprotective effect of oleuropein as an antioxidant agent on the substantia nigra in aged rats. Methods: Twenty 18-month-old Wistar rats (450-550 g) were randomly divided into control and experimental groups. The experimental group received a daily single dose of 50 mg/kg of oleuropein by oral gavage for 6 months. The control group received only distilled water. All rats were sacrificed two hours after the last gavage and the brains were removed and midbrains were cut. One part of the midbrains were homogenized and centrifuged. The tissue supernatant was assayed for lipid peroxidation (LPO) and antioxidant enzyme activities. The other part of midbrains fixed and embedded in paraffin, then processed for Nissl and immunohistochemistry (IHC) staining. Data was analyzed using SPSS by t-test. Differences were considered significant for P<0.05. Results: The level of LPO in midbrain of the rats was decreased significantly in the experimental group, but superoxide dismutase, catalase and glutathione peroxidase activities were increased in experimental group compared to control group (P<0.05). Morphometric analyses showed significantly that the experimental group had more neurons in substantia nigra pars compacta (SNc) either in Nissl or IHC staining when compared to control (P<0.05). Conclusion: The results of the present study indicate that treatment of the old rats with oleuropein reduces the oxidative damage in SNc by increasing the antioxidant enzyme activities. Key Words: Oleuropein, Aging, Dopaminergic neurons, Substantia nigra     

臭氧胁迫对不同敏感型水稻干物质积累与分配的影响

【目的】研究臭氧胁迫对不同敏感型水稻物质生产与分配的影响,为耐性水稻品种的选育提供参考。【方法】利用自然光气体熏蒸平台,以23个水稻品种或株系为供试材料,设置室内对照(臭氧浓度为10 nL/L)和臭氧浓度增高臭氧浓度为(100 nL/L)处理,研究臭氧胁迫对水稻成熟期地上部物质积累与分配的影响及其与最终生长量响应的关系。采用组内最小平方和的动态聚类方法,将所有供试材料按地上部最终生物量对臭氧胁迫的响应从小到大依次分为A、B和C三类不同敏感型水稻。【结果】与对照相比,臭氧胁迫使A、B和C类水稻成熟期地上部干质量平均分别下降19%、39%和52%,B和C类达极显著水平。臭氧胁迫使A类水稻成熟期叶片干质量略增,但使B类(–11%)、C类水稻(–25%)极显著下降。臭氧胁迫下A、B和C类水稻的茎秆和稻穗干质量均显著或极显著下降,其中茎秆干质量分别下降26%、41%和57%,稻穗干质量分别下降34%、59%和62%。臭氧胁迫使叶片占地上部干质量的比例大幅增加(+46%),而茎秆(–8%)和稻穗(–24%)占地上部干质量的比例极显著下降。臭氧处理与水稻类型对上述参数均有不同程度的交互作用,表现为A类水稻对臭氧的响应明显小于其他两类水稻。【结论】100 nL/L臭氧浓度严重影响水稻器官建成,减少光合产物向茎秆和稻穗的分配比例,但使叶片干质量比例大幅增加,臭氧熏蒸还导致茎秆机械强度明显下降。这些变化敏感水稻总体上较钝感类型水稻表现更为明显。