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2007年  第28卷  第5期

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论文
Abstract: Alpha-bungarotoxin is one of the post-synaptic neurotoxins, which widely exists in the Elapidae venom. The polymorphism of α-bungarotoxin’s cDNA sequences has been controversial in previous reports. In the present study, cloning of α-bungarotoxin gene from the genomic DNA, sequencing of five clones and analysis of their polymorphism were reported. Furthermore, we cloned and sequenced the nerve growth factor (NGF) gene from the same cDNA pool as a standard, and compared the mutation rates among different sources of α-bungarotoxin cDNAs, α-bungarotoxin genes and NGF cDNA. The results indicated that there was no diversification in the genome or comparability in the mutative points between different cDNA sequences. Therefore, we speculate that the polymorphism of α-bungarotoxin cDNA resulted neither from different transcripts, nor from RNA editing, but possibly from reverse transcript processes and gene-cloning processes.
Abstract: Double-stranded RNA activated protein kinase (PKR) is an important antiviral protein induced by interferon (IFN). PKR was discovered as the enzyme responsible for inhibition of protein synthesis. CaPKR-like is the first fish PKR-like gene isolated from crucian carp. In the present study, the expression of CaPKR-like in the tissues of crucian and grass carp were analyzed by Western blots. In both species, CaPKR-like had a very low level of constitutive expression in un-stimulated tissues, but was up-regulated in all tissues tested in animals stimulated with Poly I:C for seven days. The expression analysis revealed the same characterization of CaPKR-like as mammalian PKR genes.
The fragments of the mitochondrial ND1 and COI gene of 20 Chinese species in the subfamily Elymninae were newly amplified and sequenced in this study. Combining the homologous sequences of 4 foreign species from GenBank and using 3 species of the families Papilionidae and Parnassiidae as the outgroups, the phylogenetic trees of these Elymninae groups were reconstructed with neighbor joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesina inference (BI) methods. The results showed that the tribes Zetherini and Elymniini are closely related to each other. The tribe Lethini is not monophyletic, with the genera Lethe and Neope are closely related to the tribe Mycalesini, the genera Chonala, Tatinga, Lasiommata and Pararge form a monophyletic clade, and what is more, the Chonala and Tatinga clustered together in all the trees with support of 100% bootstrap value or 1.00 posterior probability, and should be consequently grouped into one genus.
Abstract: Oxygen/glucose deprivation (OGD) has been widely used as an in vitro model of focal ischemia, where the blood flow is severely reduced and neurons rapidly die. However, adjacent to the focal region is ‘penumbra’, where residual blood flow remains oxygen and glucose supplies are at low levels. To model this pathological genesis, we developed a partial OGD (pOGD) protocol in a rat brain slice. This model met two requirements: oxygen was partially deprived and glucose was reduced in the perfusion buffer. Therefore we investigated the effect of pOGD on gama-aminobutyric acid (GABAA) receptor-mediated inhibitory postsynaptic currents (IPSCs) in CA1 neurons of a hippocampal slice through whole-cell patch-clamp technique. We found that the amplitude and decay time of IPSCs were increased immediately during pOGD treatment. And the enhancement of IPSCs amplitude resulted from an increase of the synaptic conductance without a significant change in the reversal potential of chloride. These results suggested that the nervous system could increase inhibitory neurotransmission to offset excitation by homeostasis mechanisms during the partial oxygen and glucose attack.
In this paper,the data on the soil mites under different vegetation reclamation practices were collected using the Tullgren method, in seriously alkalinized and degraded grasslands of Songnen, Northeastern China between May and October in 2005. Using the community parameters of generic richness, abundance, diversity index, and maturity index (MI) (Mesostigmata), the community structure and its seasonal changes were described. A total of 1 104 soil mite individuals were captured and classified into 41 genera. Our results showed that fencing an enclosure and planting Puccinellia chinampoensis substantially improved soil mite communities after five years reclamation, and less mites were taken in the control treatment. Mite abundance and MI were significantly increased when P. chinampoensis was planted than under fencing enclosure treatments. MI index indicated that planting P. chinampoensis altered the ratio of K-selection of soil predatory mites after reclamation. The results suggested that planting P. chinampoensis may be more beneficial to restoring soil mite communities, than fencing enclosures in seriously alkalinized and degraded grasslands of Songnen.
A new, fanged frog Limnonectes bannaensis sp. nov. ( Holotype: CIB 570798, adult male, SVL 87.5 mm) has been recognized based on the collections from Jinghong City and Mengla County, Yunnan Province in China, which was previously recognized as L. kuhlii (Tschudi). This new species can be distinguished from the latter by a combination of the following characteristics: (1) Skin on the body is smooth, with few fine folds on the back and a few small rounded tubercles scattered on the rear of the body; (2) Dorsum is brownish or gray brown in color, black stripes are present on areas around the folds; (3) the tail of tadpoles from Mengyang have black spots, but the rear half is not black; (4) Karyotype: 2n = 22 (20 m+2 st); the chromosome length decreases gradually and does not form distinct size groups. Limnonectes kuhlii has: (1) Skin on its body is very wrinkled, covered densely with star-shaped tubercles; (2) marbled black to complete black all over the back; (3) the tadpoles from Java, the terminal half of their tail is black in color; (4) Karyotype: 2n = 26, consists of five large pairs and eight small pairs.
Abstract : A new odor frog Odorrana (Odorrana) nanjiangensis sp. nov. (Holotype: CIB610623, adult male, SVL 59.6 mm) has been recognized based on the collections from Nanjiang County, Sichuan Province in China, which was previously recognized as O. schmackeri. This new species can be distinguished from the latter by the combination of the following characteristics: (1) the sexual dimorphism ratio is smaller in size between males and females of O. nanjiangensis; 1∶1.34 (male to female), males’ mean SVL 55.6 mm, females’ mean SVL 74.6 mm, compared to the ratio of males (mean SVL 44.6 mm) to females (mean SVL 80.0 mm) of O. schmackeri is 1∶1.93, (2) vomerine teeth have two short series in O. nanjiangensis, compared to two long series in O. schmackeri; (3) dark spots present on green body back and have no light edge on O. nanjiangensis, while light-edged compared to dark spots with light edge on O. schmackeri; (4) rear of the thigh of O. nanjiangensis has large, scattered dark brown markings, compared to the rear of the thigh of O. schmackeri has small, densely marbled or spotted, dark brown markings; (5) webs of toes are rather small, web on fourth toe reaches distal sub-articulate tubercle of O. nanjiangensis, compared to the webs on the toes of O. schmackeri, which reaches the disc of the toe; (6) eggs of O. nanjiangensis are creamy white without pigment, whereas the eggs of O. schmackeri are pigmented and the animal pole is brown in color.
HIV vaccine has become one of the research hotspot for the researchers in the world. Animal model is an important tool for AIDS vaccine research. The slow progress in AIDS vaccine partially imputes to be lack of appropriate animal models. SIV/SHIV macaque model has been widely used in AIDS research. However, there are some limitations inherent in the current models that use either macaque animals or viruses. In order to exploit the potential of nonhuman primate models in AIDS vaccine development, finding a better standardization animal model is an urgent necessity in HIV research. In this review, the strategy and progress towards development of a HIV vaccine, and the present research status and applied prospects of SIV/SHIV macaque model in HIV vaccine research were summarized.
AbstractEpigenetic reprogramming has a crucial role in establishing nuclear totipotency in normal development and in cloned animals. In the current study, the method of Real-time fluorescent quantitative PCR (FQ-PCR) was applied to detect Igf2r mRNA in Madin–Darby bovine kidney(MDBK )cells after being treated with 5’-azacytidine (5’-aza, a DNA methyltransferase inhibitor). And then we used the method of Bisulfite DNA Sequencing to detect DNA methylation status of Igf-2r DMR 2(DNA differentially methylated region,DMR)and 3’UTR(3’-untranslated region,UTR)in several tissues, such as brain, liver, lung, and heart in normal and cloned cattle. Results suggested that Igf2r mRNA were up-regulated in MDBK cells after being treated with 5’-aza. DNA methylation at DMR 2 significantly varied in normal cattle tissues but without significant variation at Igf-2r 3¢-UTR. DNA methylation at Igf-2r DMR2 in cloned cattle was markedly altered compared with a normal fetus, while it was similar to a normal fetus at Igf-2r 3¢-UTR. Based on the results, it is suggested that DNA methylation inhibitor down-regulated the expression of Igf-2r in MDBK cells. In normal cattle, patterns of DNA methylation at Igf-2r DMR2 was variable in different tissues, suggesting that the mechanism of gene imprinting was differently regulated in these tissues. Results also showed that in cloned cattle, Igf-2r DMR2 DNA methylation was disrupted while the non-imprinting control region (3'-UTR) was not. It suggested that disruption of the gene imprinting control region was likely to result in the abnormalities of cloned cattle.
The laser scanning confocal mircroscope and fluorescence speotrophotometer were used to investigate the effects of the L-type calcium channel agonist 1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl] pyridine-3- carboxylic acid ((±)-Bay K8644) and antagonist nimodipine on intra-cellular calcium concentration ([Ca2+]i ) of caltured mouse astrocyetes. Bay K8644 can evidently increase the [Ca2+]i in caltured astrocytes with the doses of 0.0001mM、0.001mM and 0.01mM, whereas nimodipine can decrease the [Ca2+]i with the dose of 0.001mM、0.01mM and 0.1mM. Nimodipine also can decrease the elevation of [Ca2+]i which was elicited by KCl .Our results suggested that the effets of L-type calcium channel agonist and antagonist on astrocye are same as neurons, it indicated that astrocytes also have L-type calcium channel.
Abstract: To study the effects of glucose on the development of ICR mouse embryos in vitro. Experiment 1: ICR female mice (6-8 weeks of age) were super-ovulated with i.p. injections of PMSG and hCG, and mated overnight with males. One-cell embryos were collected at 22-26 hrs after hCG and cultured in CZB supplemented with 0, 0.5, 1.0, 3.0, 5.0 or 10 mmol/L glucose respectively. Experiment 2: One-cell embryos were collected from the oviducts of ICR female mice, super-ovulated and cultured in glucose-free CZB. The embryos,respectively at one-cell, two-cell, four-cell or morula stage,were removed from glucose-free CZB medium and placed in CZB medium supplemented with 3.0 mmol/L glucose (optimal concentration) and removed to glucose-free CZB 24 h later (except the morula stage embryo). The embryos in another group were cultured in CZB supplemented with 3.0 mmol/L glucose during the entire culture time. The embryos in the control group were continuously cultured in glucose-free CZB. Embryos were cultured for 120 h at 37℃ under 5% CO2 in sealed culture chambers and observed every 24 h under a Nikon inverted microscope. The culture efficiency was evaluated by determining the proportion of embryos reaching the four-cell (48 h), blastocyst (96 h), or hatched blastocyst (120 h) stage. The total cell numbers were counted in the blastocyst and hatched blastocyst embryos. The experiment results were: 1) There were no significant differences in the rates of four-cell embryos between every glucose-containing group and the glucose-free group. 2)The blastocyst rates of glucose-containing groups were significantly higher than that of the control. 3)The total cell numbers in the concentration group containing 3.0 mmol/L glucose were significantly higher than one another. 4)Addition of glucose from the two-cell to four-cell stage or from the four-cell to morula stage, significantly increased the blastocyst rates compared with the control. In contrast, addition of glucose from one-cell to two-cell, at morula or after morula, did not increase the blastocyst rates compared with the control. It indicates that addition of glucose to CZB does not result in two-cell block of the embryo development, and addition of glucose to CZB in a concentration as high as 10 mmol/L does not inhibit the development of ICR mouse one-cell to hatched blastocyst development. The optimal concentration of glucose added in CZB could be 3.0 mmol/L in the culture of ICR mouse embryos in vitro. Exposure of embryos to glucose, beginning at the two-cell and extending to the four-cell stage or beginning at the four-cell and extending to the morula stage, is necessary for the development of ICR mouse embryos in vitro.
Abstract: The development of the digestive tract and accessory glands in the Mandarin fish (Siniperca chuatsi) larvae from hatching to 35 days after hatch (DAH) was morphologically and histologically examined using light microscopy. Hatched at the temperature varying from 18.0 to 20.0℃, the digestive tract of the newly hatched larva of the mandarin fish was a simple closed tube under the notochord and above the posterior segment of the oval yolk sac containing the oil globule. On 2 DAH, the mouth and the anus were opened, the digestive tract run through. On 4 DAH, the epithelium of the digestive tract was differentiated, the live and pancreas appeared, and fish began to turn endogenous feeding to exogenous feeding. On 5 DAH, the larvae begun to ingest exogenous food, the digestive tract was differentiated into five portions: buccopharyngeal cavity, esophagus, stomach, anterior and posterior intestine. The yolk was gradually absorbed and disappeared on 9 DAH. During the following developmental period of the larvae, the structure and function of the digestive system became mature gradually. Infranuclear vacuoles occurred in the anterior intestine on 7 DAH and esoinophilic granulae occurred in the posterior intestine on 8 DAH, which indicates the start of lipid and protein absorption. Gastric glands were observed on 13 DAH, which indicates the passage through the juvenile period
Abstract: The water environment has important features that affect the activities of anurans. The activities of Rana kukunoris around the seasonal pond was investigated using transects, in late July and September, respectively. The transects were set in eight directions: north, south, west, east, northwest, northeast, southwest and southeast. The transects were two meters in width and 70-150 m in length. It was indicated that R. kukunoris moved around the pond in summer and there was significant negative correlation between the percentage of frog numbers and distance to the aquatic site (Pearson, adult:r = -0.479, P < 0.05; sub-adult: r = -0.480, P < 0.05). Ninety percent of the frogs recorded were distributed in an area around the pond in a radius of 110 m. In contrast to sub-adults, the adult frogs tended to dissipate away from the pond and preferred to choose the mouth of the spring as a habitat. However, there was no significant correlation between the percentage of frog numbers and the distance from the seasonal pond in autumn (Pearson, r = -0.016, P > 0.05), the percentage of frog numbers was very low and frogs preferred the mouth of the spring as a habitat.
Abstract: Parasinilabeo longiventralis, a new species is here described from He jiang basin, a tributary of the Zhujiang River (Pearl River) drainage in Fuchuan County, Guangxi Province, southern China. It can be distinguished from all other congeners by having the following combination of characteristics: maxillary barbels length is 78.3-90.4% of rostral barbels length; pelvic-fin length is 83.7-89.4% of the distance between the ventral-fin origin and to the anal-fin origin; a longitudinal wide black stripe running along the posterior lateral line and irregular brown pigments on the sides of the body.
A new freshwater goby, Rhinogobius wuyiensis sp. nov., was found in the Wuyi river(28°55′N,119°50′E)in Wuyi, Zhejiang province, China. The spot pattern on head of this species was similar to R. lentiginis, but differed from this species by a combination of characters: head with cephalic lateralis canals; vertebral count 10+16=26; anal fin has 7~9 branched fin-rays; first dorsal fin in adult male with elongate filamentous rays; head with irregular spots which usually join together;branchiostegal memberane rare with dots in male.
Abstract: Studies show that the gene evolutionary mechanisms and modes, aminoacylation routes, and evolutionary mechanisms in structure and function of many aminoacyl-tRNA synthetases (aaRS), are diverse in some bacteria and eukaryotes. Thus, further studies on these diversities will be useful in understanding protein structural and functional evolution. Although the essential mechanism responsible for these diversities is not understood, these diversities suggest that certain aspects of the biological processes between bacteria and eukaryotes require further study.
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The aim of the present study was to found the object recognition learning paradigm in KM mice and evaluate the potential usefulness of the object recognition learning paradigm in safety pharmacology. The time dependent decay of object recognition memory was characterized in KM mice. Memory retention was tested 4 h or 1 h after training in KM mice. The impairment of scopolamine on the object recognition memory was assessed in KM mice. Results show that the object recognition task can easily be performed and scopolamine impairs the object recognition memory in KM mice. The object recognition task in KM mice, which is simple, rapid, and reliable, should be of great use in safety pharmacology to detect amnesic properties of new compounds.