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991.
992.
c-mos基因在动物卵母细胞减数分裂调控中起作用,但其作用机制目前仍不清楚。本实验通过RT-PCR、免疫荧光激光共聚焦检测方法检测了猪卵母细胞在体外成熟培养过程中c-mos基因在转录水平、翻译水平上的表达以及蛋白的分布,并应用注射小干扰RNA(siRNA)方法对其进行了RNA干扰(RNAi)研究。结果显示,猪卵母细胞在体外成熟培养过程中c-mos基因mRNA量逐渐增高,电激活后6h接近完全降解;MOS(c-mos基因蛋白产物)在GV卵母细胞生发泡中有一定量的表达,生发泡破裂(GVBD)前表达量增加且开始向卵母细胞胞质弥散,成熟培养44h未成熟卵母细胞中的MOS表达量要高于成熟卵母细胞,激活后6h核区MOS明显减少,但仍然有少量MOS分布于胞质中;成熟培养前干扰c-mos基因,所用三个siRNA都能成功敲低mRNA量,分别是同时期对照组mRNA量的0.08±0.03,0.11±0.06和0.20±0.06倍,干扰后虽然没有完全剔除MOS,但MOS量比同期卵母细胞有明显下降,仍可以引发成熟卵母细胞染色体解凝集。研究结果揭示了猪卵母细胞体外成熟及发育进程中c-mos基因在转录和翻译水平上的动态表达规律,建立了猪卵母细胞c-mos基因RNAi体系,为MOS在猪卵母细胞发育过程中的功能研究建立了重要的基础。 相似文献
993.
Iorio R Scrimaglio R Rantucci E Delle Monache S Di Gaetano A Finetti N Francavilla F Santucci R Tettamanti E Colonna R 《Bioelectromagnetics》2007,28(1):72-75
Some effects of extremely low frequency electromagnetic fields (ELF-EMFs) on human spermatozoa are reported. Significant increases in the values of the motility and of the other kinematic parameters have been observed when spermatozoa were exposed to an ELF-EMF with a square waveform of 5 mT amplitude and frequency of 50 Hz. By contrast, a 5 mT sine wave (50 Hz) and a 2.5 mT square wave (50 Hz) exposure did not produce any significant effect on sperm motility. The effects induced by ELF-EMF (50 Hz; 5 mT) during the first 3 h of exposure persisted for 21 h after the end of the treatment. These results indicate that ELF-EMF exposure can improve spermatozoa motility and that this effect depends on the field characteristics. 相似文献
994.
The oviducal gland of the female of Octopus vulgaris lies about halfway along the oviduct. Progesterone and 17beta-estradiol receptors have been immunolocalized in the nuclei of the cells of the glandular compartment of previtellogenic glands. We also have evidence of FMRFamide-like and cGnRH-I-like immunoreactivity in the nerve endings that reach the oviducal gland. Moreover, we have recently shown APGWamide immunoreactivity in the glandular cells of the inner part of the oviducal gland. Here we report a review on these findings as well as our latest studies on the effect that neuropeptides may exert on the secretory activity of the oviducal gland. cAMP seems to be a possible second messenger involved in such a process. We discuss the findings of a neuropeptidergic action on the glandular cells of oviducal gland in a more complex frame of molecules, such as steroids, biogenic amines and neuromodulators, controlling the activity of the gland. 相似文献
995.
996.
Jesudason EP Baben B Ashok BS Masilamoni JG Kirubagaran R Jebaraj WC Jayakumar R 《Molecular and cellular biochemistry》2007,298(1-2):69-81
Aβ vaccination as a therapeutic intervention of Alzheimer’s has many challenges, key among them is the regulation of inflammatory
processes concomitant with excessive generation of free radicals seen during such interventions. Here we report the beneficial
effects of melatonin on inflammation associated with Aβ vaccination in the central and peripheral nervous system of mice.
Mice were divided into three groups (n = 8 in each): control, inflammation (IA), and melatonin-treated (IAM). The brain, liver, and spleen samples were collected
after 5 days for quantitative assessment of plasma lipid peroxides (LPO), an oxidative stress marker, and antioxidant enzymes
such as superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and glutathione peroxidase (Gpx). IA group mice have
shown the elevated concentration of LPO significantly while there was a reduction at antioxidant enzyme levels. In addition,
a significant (P < 0.05) reduction in neurotransmitters like dopamine (DA), 5-hydroxytryptamine (5-HT), and norepinephrine (NE) was also observed
in the IA group mice. Nevertheless, their metabolites, such as homovanillic acid (HVA) and 5-hydroxyindole acetic acid (5-HIAA)
increased significantly (P < 0.05) as compared to control. Samples were further evaluated at microscopic level to examine the neuropathological changes
by immunohistochemical methods. Melatonin treatment effectively reversed these above changes and normalized the LPO and antioxidant
enzyme levels (P < 0.05). Furthermore, melatonin salvaged the brain cells from inflammation. Our Immunohistochemical findings in the samples
of melatonin-treated animals (IAM group) indicated diminished expression of glial fibrillary acidic protein (GFAP) and nuclear
factor kappa B (NfκB) than those observed in the IA group samples. Our results suggest that administration of melatonin protects
inflammation associated with Aβ vaccination, through its direct and indirect actions and it can be an effective adjuvant in
the development of vaccination in immunotherapy for Alzheimer’s disease (AD). 相似文献
997.
Microbial Community Structure and Dynamics of Dark Fire-Cured Tobacco Fermentation 总被引:2,自引:0,他引:2
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Michele Di Giacomo Marianna Paolino Daniele Silvestro Giovanni Vigliotta Francesco Imperi Paolo Visca Pietro Alifano Dino Parente 《Applied microbiology》2007,73(3):825-837
The Italian Toscano cigar production includes a fermentation step that starts when dark fire-cured tobacco leaves are moistened and mixed with ca. 20% prefermented tobacco to form a 500-kg bulk. The dynamics of the process, lasting ca. 18 days, has never been investigated in detail, and limited information is available on microbiota involved. Here we show that Toscano fermentation is invariably associated with the following: (i) an increase in temperature, pH, and total microbial population; (ii) a decrease in reducing sugars, citric and malic acids, and nitrate content; and (iii) an increase in oxalic acid, nitrite, and tobacco-specific nitrosamine content. The microbial community structure and dynamics were investigated by culture-based and culture-independent approaches, including denaturing gradient gel electrophoresis and single-strand conformational polymorphism. Results demonstrate that fermentation is assisted by a complex microbial community, changing in structure and composition during the process. During the early phase, the moderately acidic and mesophilic environment supports the rapid growth of a yeast population predominated by Debaryomyces hansenii. At this stage, Staphylococcaceae (Jeotgalicoccus and Staphylococcus) and Lactobacillales (Aerococcus, Lactobacillus, and Weissella) are the most commonly detected bacteria. When temperature and pH increase, endospore-forming low-G+C content gram-positive bacilli (Bacillus spp.) become evident. This leads to a further pH increase and promotes growth of moderately halotolerant and alkaliphilic Actinomycetales (Corynebacterium and Yania) during the late phase. To postulate a functional role for individual microbial species assisting the fermentation process, a preliminary physiological and biochemical characterization of representative isolates was performed. 相似文献
998.
In order to define the ancestors of the Eurasian genera Axis and Rusa, the representatives of the tribe Pliocervini have been reviewed, with the exclusion of the genus Pliocervus. The fossil remains referred to Pliocervini stored in the Palaeontological Museum of Mechnikov Odessa National University and studied by Khomenko [Khomenko, I., 1913. Meotian fauna of v. Tarakliya of Bendery district. Annuaire géologique et minéralogique de la Russie. 1. The ancestors of modern and fossil Cervinae. 2. Giraffidae and Cavicornia 15, 107-132 (in Russian)] are reappraised: these remains are attributed to Cervavitus novorossiae (Khomenko, 1913). The fossil deer collected from the locality of Novoelizavetovka (Odessa region, Ukraine) and observed in the same Museum of the Odessa National University, is referred to Cervavitus variabilis Alexeev (1915).The fossil material from Shanxi and Honan provinces (China), described by Zdansky [Zdansky, O., 1925. Fossil Hirsche Chinas. Palaeontologia Sinica C 2, 1-94] and Teilhard de Chardin and Trassaert [Teilhard de Chardin, P., Trassaert, M., 1937. The Pliocene Camelidae, Giraffidae and Cervidae of southeastern Shansi.] is referred to Cervavitus shanxius Dong and Hu, 1994. The phylogenetic relationships between Pliocervini from China and the European ones are investigated on the basis of the morphological, biochronological and paleogeographical data. These elements and the suggestions of the more recent genetical and biometrical data may indicate that the origin of the two genera Axis and Rusa could be recognized into the Chinese pliocervines. 相似文献
999.
1000.