711 research outputs found
Effect of Qufeng Xuanbi Formula on experimental asthma guinea pigs' airway inflammation and Th1/Th2 cytokines
目的 观察祛风宣痹方对哮喘豚鼠气道炎症和Th1/Th2细胞因子的影响,探讨其作用机制。方法 用卵蛋白和雾化吸入致敏法,复制豚鼠哮喘模型;取肺泡灌洗液进行嗜酸性粒细胞(Eos)计数;肺组织切片HE染色形态学观察;ELASA方法检测BALF中IFN-γ和IL-4的含量。结果 模型组较正常组肺泡灌洗液(BALF)中气道Eos炎症细胞表达异常,组织形态学病变明显,IFN-γ含量显著下降,IL-4的含量明显升高;地塞迷松米组、中药高剂量组、中药低剂量组较模型组均有显著性差异,BALF中Eos的数量明显降低,组织形态学改善明显,IFN-γ含量显著升高,IL-4的含量明显下降,中药高剂量组效果强于低剂量组。结论 祛风宣痹方能减少EOS浸润,抑制气道炎症,调节Th1/Th2失衡,这可能是其阻断哮喘发生发展的机制之一。Objective: To explore the therapeutic effect and mechanism of Qufeng Xuanbi Formula on experimental asthma guinea pigs' airway inflammation and regulation Th1/Th2 imbalance in treatment of bronchia asthma. Methods: Animal models were established in guinea pigs by a combination of intraperitional injection and repeated intranasal challenges. Immune adjustment influence of medicine on Th1/Th2 imbalance was observed.Eos in BALF were counted and tissue slice dyed with HE were observed; Content of IFN-γand IL-4 were detected by ELASA. Results: Compared with normal group, the alveolar lavage fluid (BALF) in the marked increase in the number of Eos, histomorphology lesions, obviously abnormal Eos of the airway inflammatory cells express; the level of IFN-γwas dramatically decreased, neutrophil and level of IL- 4 were all significantly increased in the BALF. DXM group, high and low dose group are significant different compared with model group (P<0.01), However, the percentages of EOS and level of IFN-γwas dramatically increased, the level of IL-4 was dramatically decreased (P<0.01), high dose group‘s effect is better than the low dose group. Conclusion: Qufeng Xuanbi Formula can reduce the EOS infiltration, inhibit airway inflammation, regulate Th1/Th2 imbalance, it could be one of the blocking mechanism of occurrence and development of asthma.
The Binding of Platinum (II) Complexes to Rabbit Skeletal Muscle G-Actin Induces Conformation Changes
The binding of cis-diamminedichloroplatinum (DDCP) and cis-diaquodiammine platinum (DADP) to
rabbit skeletal muscle G-actin and the consequent conformation changes were studied as the function of the
Pt/actin molar ratio (R) and time by intrinsic and NPM labeled fluorescence, CD spectra as well as gelfiltration
chromatography. The results indicated that the unhydrolyzed DDCP can react with G-actin in
presence of Cl- ion. The reaction differs from that of its hydrolysis product DADP in a higher specificity and
a lower capacity. Both of them induced exposure of the tryptophane residues and labeled Cys374 and the
increase in α-helix content depending on R, but the conformation changes caused by DADP are more
significant than DDCP at the same R. These are related to the binding of DADP to groups other than thiols.
The rate constants of conformation change suggested that DADP quenched the intrinsic fluorescence more
rapid. The temporal change in fluorescence of NPM labeled actin has a biphasic feature: in the first 16
minutes, the fluorescence was quenched, then it recovered slowly, indicating a multi-step reaction including
high affinity platinum binding → labeled Cys374 moving to hydrophilic environment → low affinity platinum
binding → Cys374-related conformation compacting in sequence
Draft Genome of the Leopard Gecko, \u3cem\u3eEublepharis Macularius\u3c/em\u3e
Background
Geckos are among the most species-rich reptile groups and the sister clade to all other lizards and snakes. Geckos possess a suite of distinctive characteristics, including adhesive digits, nocturnal activity, hard, calcareous eggshells, and a lack of eyelids. However, one gecko clade, the Eublepharidae, appears to be the exception to most of these ‘rules’ and lacks adhesive toe pads, has eyelids, and lays eggs with soft, leathery eggshells. These differences make eublepharids an important component of any investigation into the underlying genomic innovations contributing to the distinctive phenotypes in ‘typical’ geckos. Findings
We report high-depth genome sequencing, assembly, and annotation for a male leopard gecko, Eublepharis macularius (Eublepharidae). Illumina sequence data were generated from seven insert libraries (ranging from 170 to 20 kb), representing a raw sequencing depth of 136X from 303 Gb of data, reduced to 84X and 187 Gb after filtering. The assembled genome of 2.02 Gb was close to the 2.23 Gb estimated by k-mer analysis. Scaffold and contig N50 sizes of 664 and 20 kb, respectively, were compble to the previously published Gekko japonicus genome. Repetitive elements accounted for 42 % of the genome. Gene annotation yielded 24,755 protein-coding genes, of which 93 % were functionally annotated. CEGMA and BUSCO assessment showed that our assembly captured 91 % (225 of 248) of the core eukaryotic genes, and 76 % of vertebrate universal single-copy orthologs. Conclusions
Assembly of the leopard gecko genome provides a valuable resource for future comptive genomic studies of geckos and other squamate reptiles
Mathematical Analysis for a Discrete Predator-Prey Model with Time Delay and Holling II Functional Response
This paper is concerned with a discrete predator-prey model with Holling II functional response and delays. Applying Gaines and Mawhin's continuation theorem of coincidence degree theory and the method of Lyapunov function, we obtain some sufficient conditions for the existence global asymptotic stability of positive periodic solutions of the model
Large deflection and rotation of Timoshenko beams with frictional end supports under three-point bending
Reply to “Comments on ‘Large deflection and rotation of Timoshenko beams with frictional end supports under three-point bending’ ” [C. R. Mecanique 345 (2017), doi:10.1016/j.crme.2017.01.004]
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