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231.
S Y Yan Z R Mao H Y Yang M A Tu S H Li G P Huang G S Li L Guo G Q Jin R F He 《The International journal of developmental biology》1991,35(4):429-435
The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence. 相似文献
232.
Jing Chen Cheng-Shi Jiang Wen-Quan Ma Li-Xin Gao Jing-Xu Gong Jing-Ya Li Jia Li Yue-Wei Guo 《Bioorganic & medicinal chemistry letters》2013,23(18):5061-5065
Bruguiesulfurol (1), a cyclic 4-hydroxy-dithiosulfonate isolated from mangrove plant Bruguiera gymnorrhiza, was concisely synthesized for the first time in four steps, and a series of its synthetic derivatives were evaluated for in vitro inhibitory effects on PTP1B and related PTPs. Some derivatives were found to have improved pharmacological profile compared with hit 1. Among them, 5a showed the potent selectivity towards PTP1B over other PTPs, including TCPTP, and 7j exhibited the strongest PTP1B inhibitory activity with an IC50 value of 4.54 μM. 相似文献
233.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
234.
Liang Guo Jia-Xin Huang Yuan Liu Xi Li Shui-Rong Zhou Shu-Wen Qian Yang Liu Hao Zhu Hai-Yan Huang Yong-Jun Dang Qi-Qun Tang 《Molecular and cellular biology》2013,33(16):3180-3190
Autophagy is a highly conserved self-digestion pathway involved in various physiological and pathophysiological processes. Recent studies have implicated a pivotal role of autophagy in adipocyte differentiation, but the molecular mechanism for its role and how it is regulated during this process are not clear. Here, we show that CCAAT /enhancer-binding protein β (C/EBPβ), an important adipogenic factor, is required for the activation of autophagy during 3T3-L1 adipocyte differentiation. An autophagy-related gene, Atg4b, is identified as a de novo target gene of C/EBPβ and is shown to play an important role in 3T3-L1 adipocyte differentiation. Furthermore, autophagy is required for the degradation of Klf2 and Klf3, two negative regulators of adipocyte differentiation, which is mediated by the adaptor protein p62/SQSTM1. Importantly, the regulation of autophagy by C/EBPβ and the role of autophagy in Klf2/3 degradation and in adipogenesis are further confirmed in mouse models. Our data describe a novel function of C/EBPβ in regulating autophagy and reveal the mechanism of autophagy during adipocyte differentiation. These new insights into the molecular mechanism of adipose tissue development provide a functional pathway with therapeutic potential against obesity and its related metabolic disorders. 相似文献
235.
Ya-Nan Chang Haili Guo Juan Li Yan Song Mingyi Zhang Junjiang Jin Gengmei Xing Yuliang Zhao 《PloS one》2013,8(10)
The nature of macrophage allows the possibility that this cell type could be used as drug delivery system to track therapeutic drug nanoparticles (NPs) in cancer. However, there is no existing research on the regulation between effective loading of NPs and targeted delivery of macrophages. Here, we investigated the important parameters of intracellular NP quantity and the vector migration rate. Macrophage loading capacity was obtained by comparing the uptake quantity of varisized NPs, and the delivery ability of loaded cells was determined by measuring vector migration rates. We observed a positive correlation between the size of NPs and directed macrophage migration. Our findings suggest that the molecular mechanism of migration vector rate regulation involved increased expression levels of colony-stimulating factor-1 (CSF-1) receptor and integrin induced by 100-nm and 500-nm particles. The ability of macrophages uptake to varisized NPs showed the opposite trend, with the increased vector rate of cell migration influenced by NPs. We are able to demonstrate the important balance between effective macrophage loading and targeted delivery. By adjusting the balance parameters, it will be possible to utilize NPs in macrophage-mediated disease diagnosis and therapy. 相似文献
236.
The partial genomic library of Acetobacter suboxydans was constructed using Yeast\| E.coli shuttle plasmid YEp352 as vector.Two positive transformants,designated as DH5α(pAD91) and DH5α(pAD98),were obtained by screening the growth of transformants on the agar plate in which D\|arabitol was used as the sole carbon source.The results of Southern blot and restriction endonuclease analysis showed that the two recombinants are identical.The insert is about 2.3kb.Arabitol dehydrogenase activity assay indic… 相似文献
237.
Guo S Cichy SB He X Yang Q Ragland M Ghosh AK Johnson PF Unterman TG 《The Journal of biological chemistry》2001,276(11):8516-8523
238.
Fan Ding Wen-Li Jiang Xian-Guo Guo Rong Fan Cheng-Fu Zhao Zhi-Wei Zhang Ke-Yu Mao Rong Xiang 《The Korean journal of parasitology》2021,59(4):377
This paper is to illustrate the infestation and related ecological characteristics of chigger mites on the Asian house rat (Rattus tanezumi). A total of 17,221 chigger mites were collected from 2,761 R. tanezumi rats, and then identified as 131 species and 19 genera in 2 families. Leptotrombidium deliense, the most powerful vector of scrub typhus in China, was the first major dominant species on R. tanezumi. All the dominant mite species were of an aggregated distribution among different individuals of R. tanezumi. The species composition and infestations of chiggers on R. tanezumi varied along different geographical regions, habitats and altitudes. The species-abundance distribution of the chigger mite community was successfully fitted and the theoretical curve equation was Ŝ (R)=37e−(0.28R)². The total chigger species on R. tanezumi were estimated to be 199 species or 234 species, and this further suggested that R. tanezumi has a great potential to harbor abundant species of chigger mites. The results of the species-plot relationship indicated that the chigger mite community on R. tanezumi in Yunnan was an uneven community with very high heterogeneity. Wide geographical regions with large host samples are recommended in the investigations of chigger mites. 相似文献
239.
Xu Y Zhang Y Guo Z Yin H Zeng K Wang L Luo J Zhu Q Wu L Zhang X Chen D 《Neurochemical research》2012,37(3):665-670
Recent studies suggest that angiogenesis and vascular endothelial growth factor (VEGF) are involved in the pathophysiology of epilepsy. However, relatively little data are available linking placenta growth factor (PIGF) with epilepsy. In this study, we assessed concentrations of PIGF in cerebrospinal fluid (CSF) of 60 epileptic patients and 24 non-seizure subjects using sandwich enzyme-linked immunosorbent assays. Epileptic patients in general had higher concentration of CSF-PIGF than controls (7.95 ± 0.88 ng/l vs. 5.87 ± 0.79 ng/l, P < 0.01). CSF-PIGF level in secondary epileptic patients (8.59 ± 1.26 ng/l) was higher than that in idiopathic epileptic patients (7.62 ± 0.20 ng/l) (P < 0.05). In idiopathic epilepsy, CSF-PIGF level in patients with high seizure frequency was higher than those in patients with low seizure frequency and seizure-free in recent 3 years (7.78 ± 0.23 ng/l vs. 7.49 ± 0.09 ng/l and 7.59 ± 0.10 ng/l, P < 0.05). Concentration of CSF-PIGF in patients with a disease duration of > 5 years was higher than those in patients with durations of 1-5 years and <1 year (7.72 ± 0.20 ng/l vs. 7.52 ± 0.09 ng/l and 7.41 ± 0.07 ng/l, P < 0.05). These results indicate that preexisting brain damage, seizure frequency and disease duration are important factors contributing to elevated PIGF. 相似文献
240.
It has been known that Rho-associated protein kinase (ROCK) signaling regulates the migration of vascular smooth muscle cells (VSMCs). However, the isoform-specific roles of ROCK and its underlying mechanism in VSMC migration are not well understood. The current study thus aimed to investigate the roles of ROCK1/2 and their relationship to the MAPK signaling pathway in platelet-derived growth factor (PDGF)-induced rat aorta VSMC migration by manipulating ROCK gene expression. The results revealed that ROCK1 small interfering ribonucleic acid (siRNA) rather than ROCK2 siRNA decreased PDGF-BB-generated VSMC migration, and upregulation of ROCK1 expression via transfection of constructed pEGFP-C1/ROCK1 plasmid further increased the migration of PDGF-BB-treated VSMCs. In PDGF-treated VSMCs, ROCK1 siRNA did not affect the phosphorylation levels of ERK and p38 in the cytoplasm, but decreased the level of ERK phosphorylation in the nucleus. These findings demonstrate that activated ROCK1 can promote VSMC migration through facilitating phosphorylation and nuclear translocation of ERK protein. 相似文献