百合组培中鳞片处理及其颜色变化与鳞茎形成的关系

 研究了百合鳞片发育程度、切割段数、形态及生理变化、培养基的P 和K含量与鳞茎形成的关系。结果表明: 取中层鳞片、每片横切6 段的繁殖系数最高, 基部鳞片结鳞茎数最多, 且鳞茎发生最早。鳞片由基部向顶部繁殖系数递减。培养过程中鳞片颜色和形态变化依次为乳白色、浅黄、浅紫色、绿紫、鳞片干枯、鳞茎增大, 鳞片由浅黄变为绿紫色过程中叶绿素含量增加, 淀粉和可溶性糖含量下降。适当增加培养基中P、K的含量可提高鳞茎形成的数量和质量。     

球根海棠离体培养的形态发生研究

 球根海棠外植体可在同一条件下同时诱导不定芽和胚状体, 经间接途径和直接途径的体细胞胚胎发生频率均很高, 体细胞胚为单细胞起源或多细胞起源。以再生嫩叶为继代中间体, 在较高温度(28 ℃) 下诱导, 可建立高效扩繁体系。纵切芽丛继代形成大量愈伤组织, 愈伤组织继代半年后几乎完全丧失分化能力, 发生激素驯化作用, 而且愈伤组织细胞染色体数目已发生广泛变异。     

60%敌草隆·环嗪酮可湿性粉剂的高效液相色谱分析方法

反相高效液相色谱法测定60%敌草隆·环嗪酮可湿性粉剂有效成分含量,流动相为甲醇和水(57∶43),波长为254nm,环嗪酮和敌草隆的标准偏差分别为0.07和0.052;变异系数分别为0.53%和0.11%;平均回收率分别为98.9%和99.2%。线性相关系数分别为0.9999和0.9995。     

Taurine reduced oxygen free radical production induced by homocysteine in electron transport chain and homocysteine inhibites taurine transporter in mitochondria membrane

AIM: To observe effects of homocysteine and antagonized effects of taurine on electronic leakage and free radical production in myocardial mitochondria. METHODS: Myocardial mitochondria of rat heart was isolated, and was broken by supersonic wave to prepare submitochondria. Recombinant of succinic acid cytochrome c reductase was prepared with mitochondria of porcine heart. They were co-incubated with homocysteine and/or taurine with various concentration. The H₂O₂ and O₂^- were determined by chemiluminescence methods. The taurine transporter of heart mitochondria and its propert, and effects of homocysteine on its function were studied with glass filter. RESULTS: Homocysteine stimulated oxygen free radical production in heart mitochondria, submitochondria, and succinic acid cytochrome c in a concentration-dependent manner. Although taurine itself did not affect oxygen free radical production, taurine did inhibit oxygen free radical production in mitochondria, submitochondria and succinic acid cytochrome c in a concentration-dependent manner. Taurine transporters of Na⁺-dependent were existed in mitochondria membrane. Homocysteine inhibited taurine transtport in mitochondria in a concentration-dependent manner. CONCLUSIONS: Taurine inhibited electronic leakage and oxygen free radical production induced by homocysteine in electron transport chain. There were taurine transporters in mitochondria membrane, and transport functions of taurine transporter were inhibited by homocysteine.     

细胞因子对小尾寒羊胎盘成熟的影响

为了研究细胞因子对小尾寒羊胎盘成熟的影响 ,本实验采用液相竞争法和平衡法 ,对小尾寒羊空怀期 (n=5 )和妊娠期 (n=13)第 85天、10 5天、12 5天、14 0天和 15 0天 (足月 )时的血清白细胞介素 - 1β(IL - 1β)、白细胞介素 - 6 (IL - 6 )和肿瘤坏死因子(TNF)的含量分别进行检测。结果表明 ,IL - 1β和 IL - 6含量在 12 5天时与对照组间差异极显著 (P<0 .0 1) ,TNF含量在各时期与对照组差异均显著 (P<0 .0 1或 P<0 .0 5 )。随着妊娠过程的进展 ,三种细胞因子含量逐渐增加 ,12 5天时达到最高值 ,分别为 0 .390± 0 .196 ng/ ml,5 79.8± 15 2 .8pg/ ml和 2 .348± 0 .396 ng/ ml。而后逐渐下降 ,到足月前略有回升 ,但仍低于 12 5天时的最高值。由此看出小尾寒羊在妊娠期间 ,细胞因子与妊娠之间有着密切的关系 ,前者对于维持妊娠起到重要作用。由于 14 0天至足月3种细胞因子基本稳定 ,这表明胎盘于 14 0天左右达到成熟 ,IL- 1β和 IL- 6与启动分娩有关 ,而 TNF可能参与小尾寒羊分娩的启动。     

A mutation confers Monochoria vaginalis resistance to sulfonylureas that target acetolactate synthase

Acetolactate synthase (ALS) is the target enzyme for four distinct families of compounds: sulfonylureas (SUs), imidazolinones, triazolopyrimidine sulfonanilides, and pyrimidinyl oxybenzoates. We cloned and sequenced the fragments encoding ALS genes from biotypes of Monochoria vaginalis susceptible (S) and resistant (R) to SU-herbicides. The nucleotide sequences of the 39 bp Domain A region for R M. vaginalis biotype differed from that of the S biotype by a single nucleotide substitution at variable Pro codon of Domain A (CCT to TCT), predicting a Pro in the S but a Ser in the R biotype. No nucleotide differences between S and R M. vaginalis were observed in Domain D. We suggest that the amino acid substitution at Domain A region is responsible for resistance to SU-herbicides in M. vaginalis collected from Ushiku City, Ibaraki Prefecture, Japan.     

小叶锦鸡儿根瘤固氮活性的动态变化

对多年生小叶锦鸡儿不同生育期根瘤固氮能力、不同树龄小叶锦鸡儿根瘤固氮能力进行调查,结果表明:开花期固氮酶活性最高,此时土壤含氮量和植株含氮量最高;新瘤多发生于果后营养期,植株生物量的峰值出现在结实期;二年生和五年生植株的根瘤固氮能力强于三年、四年生植株,随生长年限的延长,植株生物量逐渐增大,含氮量呈小幅度下降趋势。     

马动脉炎病毒RT-PCR检测方法的建立

根据已报道的马动脉炎病毒基因组保守基因核苷酸序列，设计并合成了1对引物，通过对影响PCR扩增因素的筛选，成功地从病毒感染的细胞中扩增出约200bp的片段，与理论设计值(204bp)大小一致。而正常的RK-13、BHK-21和Vero细胞和同为动脉炎病毒科的猪繁殖与呼吸道综合征病毒(PRRSV)作为对照的扩增结果均为阴性。敏感性试验表明，该方法可以检测出10^-4个TCID50的病毒含量，说明具有较好的敏感性。     

隐性白肉鸡羽速自别雌雄系的选育(1)

本研究根据现代遗传学基因测交理论,共用32只表型慢羽公鸡与245只快羽母鸡组成测交试验.结果表明,所测的32只公鸡无一只为纯合慢羽基因型.但发现测交后代的快慢羽分布比例与孟德尔遗传上的分离定律完全吻合.同时通过混合精液输精,实施扩群繁育,其中选留慢羽种母雏1460只,表型慢羽种公雏150只,从而为建立隐性白鸡慢羽系奠定了基础.     

Canine GM2‐Gangliosidosis Sandhoff Disease Associated with a 3‐Base Pair Deletion in the HEXB Gene

Background

GM2‐gangliosidosis is a fatal neurodegenerative lysosomal storage disease (LSD) caused by deficiency of either β‐hexosaminidase A (Hex‐A) and β‐hexosaminidase B (Hex‐B) together, or the GM2 activator protein. Clinical signs can be variable and are not pathognomonic for the specific, causal deficiency.

Objectives

To characterize the phenotype and genotype of GM2‐gangliosidosis disease in an affected dog.

Animals

One affected Shiba Inu and a clinically healthy dog.

Methods

Clinical and neurologic evaluation, brain magnetic resonance imaging (MRI), assays of lysosomal enzyme activities, and sequencing of all coding regions of HEXA, HEXB, and GM2A genes.

Results

A 14‐month‐old, female Shiba Inu presented with clinical signs resembling GM2‐gangliosidosis in humans and GM1‐gangliosidosis in the Shiba Inu. Magnetic resonance imaging (MRI) of the dog's brain indicated neurodegenerative disease, and evaluation of cerebrospinal fluid (CSF) identified storage granules in leukocytes. Lysosomal enzyme assays of plasma and leukocytes showed deficiencies of Hex‐A and Hex‐B activities in both tissues. Genetic analysis identified a homozygous, 3‐base pair deletion in the HEXB gene (c.618‐620delCCT).

Conclusions and Clinical Importance

Clinical, biochemical, and molecular features are characterized in a Shiba Inu with GM2‐gangliosidosis. The deletion of 3 adjacent base pairs in HEXB predicts the loss of a leucine residue at amino acid position 207 (p.Leu207del) supporting the hypothesis that GM2‐gangliosidosis seen in this dog is the Sandhoff type. Because GM1‐gangliosidosis also exists in this breed with almost identical clinical signs, genetic testing for both GM1‐ and GM2‐gangliosidosis should be considered to make a definitive diagnosis.