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101.
Previous work found that high‐molecular‐weight fractions in the egg extract of Latrodectus tredecimguttatus exhibited strong toxicities. For investigating the possible relationship of proteins in the eggs with the toxic effect, the protein composition of the eggs was analyzed using proteomic strategies and compared with that of the spider's venom. SDS‐PAGE showed that the proteins of eggs were primarily distributed in the molecular weight range of higher than 55 kDa as well as around 34 kDa, having high abundance proteins with molecular weights of about 60 kDa and 130 kDa. A total of 157 proteins were identified from the egg extract, which were involved in important cellular functions and processes including catalysis, transport, and metabolism regulation. Comparison indicated that the protein composition of eggs is more complex than that of venom, and there are few similarities between the protein composition of the two materials, demonstrating that the eggs have their own distinct toxic mechanism. © 2012Wiley Periodicals, Inc. J BiochemMol Toxicol 26:510‐515, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21460  相似文献   
102.
IL-10 is a potent immunoregulatory cytokine attenuating a wide range of immune effector and inflammatory responses. In the present study, we assess whether endogenous levels of IL-10 function to regulate the incidence and severity of collagen-induced arthritis. DBA/1 wildtype (WT), heterozygous (IL-10+/-) and homozygous (IL-10-/-) IL-10-deficient mice were immunized with type II collagen. Development of arthritis was monitored over time, and collagen-specific cytokine production and anticollagen antibodies were assessed. Arthritis developed progressively in mice immunized with collagen, and 100% of the WT, IL-10+/-, and IL-10-/- mice were arthritic at 35 days. However, the severity of arthritis in the IL-10-/- mice was significantly greater than that in WT or IL-1+/- animals. Disease severity was associated with reduced IFN-γ levels and a dramatic increase in CD11b-positive macrophages. Paradoxically, both the IgG1 and IgG2a anticollagen antibody responses were also significantly reduced. These data demonstrate that IL-10 is capable of controlling disease severity through a mechanism that involves IFN-γ. Since IL-10 levels are elevated in rheumatoid arthritis synovial fluid, these findings may have relevance to rheumatoid arthritis.  相似文献   
103.
Porcine orthoreoviruses belong to the family Reoviridae and cause mainly mild enteritis in piglets. We present here the complete genome sequence of a novel porcine orthoreovirus strain (GD-1) isolated from a piglet in southern China. Our data will facilitate future investigations of the molecular characteristics and epidemiology of porcine orthoreoviruses.  相似文献   
104.
Several recent studies suggest the isolation of stem cells in skeletal muscle, but the functional properties of these muscle-derived stem cells is still unclear. In the present study, we report the purification of muscle-derived stem cells from the mdx mouse, an animal model for Duchenne muscular dystrophy. We show that enrichment of desmin(+) cells using the preplate technique from mouse primary muscle cell culture also enriches a cell population expressing CD34 and Bcl-2. The CD34(+) cells and Bcl-2(+) cells were found to reside within the basal lamina, where satellite cells are normally found. Clonal isolation and characterization from this CD34(+)Bcl-2(+) enriched population yielded a putative muscle-derived stem cell, mc13, that is capable of differentiating into both myogenic and osteogenic lineage in vitro and in vivo. The mc13 cells are c-kit and CD45 negative and express: desmin, c-met and MNF, three markers expressed in early myogenic progenitors; Flk-1, a mouse homologue of KDR recently identified in humans as a key marker in hematopoietic cells with stem cell-like characteristics; and Sca-1, a marker for both skeletal muscle and hematopoietic stem cells. Intramuscular, and more importantly, intravenous injection of mc13 cells result in muscle regeneration and partial restoration of dystrophin in mdx mice. Transplantation of mc13 cells engineered to secrete osteogenic protein differentiate in osteogenic lineage and accelerate healing of a skull defect in SCID mice. Taken together, these results suggest the isolation of a population of muscle-derived stem cells capable of improving both muscle regeneration and bone healing.  相似文献   
105.
Xu  Xiuwen  Cao  Xiaojuan  Gao  Jian 《Transgenic research》2019,28(3-4):341-356

CRISPR/Cas9 system has been developed as a highly efficient genome editing technology to specifically induce mutations in a few aquaculture species. In this study, we described induction of targeted gene (namely tyrosinase, tyr) mutations in large-scale loach Paramisgurnus dabryanus, an important aquaculture fish species and a potential model organism for studies of intestinal air-breathing function, using the CRISPR/Cas9 system. Tyr gene in large-scale loach was firstly cloned and then its expressions were investigated. Two guide RNAs (gRNAs) were designed and separately transformed with Cas9 in the loach. 89.4% and 96.1% of injected loach juveniles respectively displayed a graded loss of pigmentation for the two gRNAs, in other words, for target 1 and target 2. We classified the injected loach juveniles into five groups according to their skin color phenotypes, including four albino groups and one wild-type-like group. And one of them was clear albino group, which was of high ornamental and commercial value. More than 50 clones for each albino transformant with a visible phenotype in each target were randomly selected and sequenced. Results obtained here showed that along with the increase of pigmentation, wild-type alleles appeared in the injected loach juveniles more often and insertion/deletion alleles less frequently. This study demonstrated that CRISPR/Cas9 system could be practically performed to modify large-scale loach tyr to produce an albino mutant of high ornamental and commercial value, and for the first time showed successful use of the CRISPR/Cas9 system for genome editing in a Cobitidae species.

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106.
曹巍 《生物技术通讯》2000,11(2):150-153
本概述了近年来生物制品研制领域的新动态,包括1999年我国新药研制相关法规的修订、有军事背景的生物制品的开发和研制,及在生物药物研制中值得重视的新生物技术领域。另外,介绍了生物制品的知识产权保护情况及如何查找生物技术专利资源。  相似文献   
107.
霍乱毒素A基因内部翻译调控元件具有翻译起始功能   总被引:3,自引:0,他引:3  
通过大肠杆菌体外转录-体外翻译系统,证明霍乱毒素A基因内部的翻译调控元件具有翻译起始功能,且其翻译起始效率较ctxA基因高得多,当ctxA的起始密码突变时,从该元件起始的翻译效率下降,说明基因内翻译起以ctxA翻译起始的调控。结果进一步证实了霍乱毒素A、B亚工比例表达调控的翻译弱化-翻译偶联机理。  相似文献   
108.
Plant lipid transfer proteins (LTPs) are a class of proteins whose functions are still unknown. Some are proposed to have antimicrobial activities. To understand whether LTP110, a rice LTP that we previously identified from rice leaves, plays a role in the protection function against some serious rice pathogens, we investigated the antifungal and antibacterial properties of LTP110. A cDNA sequence, encoding the mature peptide of LTP110, was cloned into the Impact-CN prokaryotic expression system. The purified protein was used for an in vitro inhibition test against rice pathogens, Pyricularia oryzae and Xanthomonas oryzae. The results showed that LTP110 inhibited the germination of Pyricularia oryzae spores, and its inhibitory activity decreased in the presence of a divalent cation. This suggests that the antifungal activity is affected by ions in the media; LTP110 only slightly inhibited the growth of Xanthomonas oryzae. However, the addition of LTP110 to cultured Chinese hamster ovarian cells did not retard growth, suggesting that the toxicity of LTP110 is only restricted to some cell types. Its antimicrobial activity is potentially due to interactions between LTP and microbe-specific structures.  相似文献   
109.
Six phenolic compounds isolated from Curculigo orchioides, including 2,6-dimethoxy benzoic acid (1), curculigoside A (2), curculigoside B (3), curculigine A (4), curculigine D (5) and 3,3′,5,5′-tetramethoxy-7,9′:7′,9-diepoxylignan-4,4′-di-O-β-d-glucopyranoside (6), together with the ethanol extract of Curculigo orchioides were evaluated for their activity on osteoblasts in neonatal rat calvaria cultures and multinucleated osteoclasts derived from rat marrow cells so as to characterize the antiosteoporotic components of this plant and explore the relationship of chemical structure with antiosteoporotic activity. The proliferation of osteoblast was assayed by MTT methods. The activity of ALP (alkaline phosphatase) and TRAP (tartrate-resistant acid phosphatase) was measured by p-nitrophenyl sodium phosphate assay. The TRAP stain was used to identify osteoclast in morphology. The resorption pit area on the bone slices formed by osteoclast was measured by computer image processing. The ethanol extract exhibited stimulatory effect on both the osteoblast proliferation and the ALP activity. Six compounds all increased the osteoblast proliferation, and compounds (1), (2) and (4) also slightly increased the osteoblastic ALP activity. Compounds (1), (2), (3), (6) and the ethanol extract decreased area of bone resorption pit, osteoclastic formation and TRAP activity. These results indicated that phenolic compounds are antiosteoporotic chemical constituents from Curculigo orchioides, and their activities are related with chemical structures.  相似文献   
110.
The translationally controlled tumor protein (TCTP) is an important component of the target of rapamycin (TOR) signaling pathway, the major regulator of cell growth in animals and fungi. Despite its relevance, knowledge on plant TCTP homologs is still limited. In the present study, the full-length BoTCTP cDNA was isolated from a cabbage (Brassica oleracea L.) cDNA library. The BoTCTP cDNA encodes a polypeptide of 168 amino acids and shared the highly conserved GTPase binding surface in all of the species analyzed. Northern blotting analysis showed that BoTCTP was specifically expressed in the root and stem. Furthermore, the expression of BoTCTP could be obviously enhanced by stress stimuli, including high temperature and salt stresses, while no significant changes in the BoTCTP expression were observed under ABA stress. Functional analysis of BoTCTP was performed by the silencing of BoTCTP using RNA interference (RNAi) and the BoTCTP RNAi plants exhibited reduced vegetative growth rate and decreased tolerance of the cold, high temperature, and salt stresses. The reported results clearly suggest that the BoTCTP gene is involved in the regulation of both growth and stress response in cabbage.  相似文献   
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