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Bone is a very common metastatic site for breast cancer. In bone metastasis, there is a vicious circle wherein bone-residing metastatic cells stimulate osteoclast-mediated bone resorption, and bone-derived growth factors released from resorbed bone promote tumor growth. The contribution of tumor angiogenesis in the growth of bone metastases is, however, unknown. By using an experimental model of bone metastasis caused by MDA-MB-231/B02 breast cancer cells that quite closely mimics the conditions likely to occur in naturally arising metastatic human breast cancers, we demonstrate here that when MDA-MB-231/B02 cells were engineered to produce at the bone metastatic site an angiogenesis inhibitor, angiostatin, there was a marked inhibition in the extent of skeletal lesions. Inhibition of skeletal lesions came with a pronounced reduction in tumor burden in bone. However, although angiostatin produced by MDA-MB-231/B02 cells was effective at inhibiting in vitro endothelial cell proliferation and in vivo angiogenesis in a Matrigel implant model, we have shown that it inhibited cancer-induced bone destruction through a direct inhibition of osteoclast activity and generation. Overall, these results indicate that, besides its well known anti-angiogenic activity, angiostatin must also be considered as a very effective inhibitor of bone resorption, broadening its potential clinical use in cancer therapy.  相似文献   
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Abstract: Mitogen-activated protein (MAP) kinases have been implicated in multiple responses to extracellular stimuli. In this study we show that MAP kinase activity is enhanced after a KCI pulse. This activation correlates with an increased tyrosine phosphorylation of a 42-kDa protein as determined by antiphosphotyrosine immunoblot. The same band is found in an anti-MAP kinase immunoblot. Activity is enhanced within 1 min, reaches a maximum at 2 min, and returns to basal level after 10 min. A second peak of activity is observed between 12 and 30 min. The activation is completely blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), showing the involvement of the AMPA type of glutamate receptor. Partial inhibition of MAP kinase activation by 2-amino-5-phosphonovalerate (APV) also shows the involvement of the NMDA receptor. Because the KCI pulse used induces long-term potentiation (LTP) in rat hippocampal slice, we conclude that MAP kinase may be involved in neuronal transduction events leading to LTP.  相似文献   
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Haematology parameters (N = 24) and serum biochemistry parameters (N = 35) were determined for wild Eurasian beavers (Castor fiber), between 6 months – 12 years old. Of the population tested in this study, N = 18 Eurasian beavers were from Norway and N = 17 originating from Bavaria but now living extensively in a reserve in England. All blood samples were collected from beavers via the ventral tail vein. All beavers were chemically restrained using inhalant isoflurane in 100% oxygen prior to blood sampling. Results were determined for haematological and serum biochemical parameters for the species and were compared between the two different populations with differences in means estimated and significant differences being noted. Standard blood parameters for the Eurasian beaver were determined and their ranges characterised using percentiles. Whilst the majority of blood parameters between the two populations showed no significant variation, haemoglobin, packed cell volume, mean cell haemoglobin and white blood cell counts showed significantly greater values (p<0.01) in the Bavarian origin population than the Norwegian; neutrophil counts, alpha 2 globulins, cholesterol, sodium: potassium ratios and phosphorus levels showed significantly (p<0.05) greater values in Bavarian versus Norwegian; and potassium, bile acids, gamma globulins, urea, creatinine and total calcium values levels showed significantly (p<0.05) greater values in Norwegian versus Bavarian relict populations. No significant differences were noted between male and female beavers or between sexually immature (<3 years old) and sexually mature (≥3 years old) beavers in the animals sampled. With Eurasian beaver reintroduction encouraged by legislation throughout Europe, knowledge of baseline blood values for the species and any variations therein is essential when assessing their health and welfare and the success or failure of any reintroduction program. This is the first study to produce base-line blood values and their variations for the Eurasian beaver.  相似文献   
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Human induced pluripotent stem cells (iPSCs) are potential renewable sources of hepatocytes for drug development and cell therapy. Differentiation of human iPSCs into different developmental stages of hepatic cells has been achieved and improved during the last several years. We have recently demonstrated the liver engraftment and regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo. Here we describe the in vitro and in vivo activities of hepatic cells derived from patient specific iPSCs, including multiple lines established from either inherited or acquired liver diseases, and discuss basic and clinical applications of these cells for disease modeling, drug screening and discovery, gene therapy and cell replacement therapy.  相似文献   
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Termites are an important component of tropical rain forests, and have been included in many studies focusing on the influence of human disturbance. Their distribution among primary rain forest has, however, rarely been investigated. Here we studied the termite fauna in seven mostly undisturbed forest sites, representing several rain forest types. Overall, approximately 70 percent of species were soil‐feeders and 25 percent were wood‐feeders, the remaining 5 percent being classified here as litter‐feeders. Termite species richness did not differ significantly among sites, but sites differed in termite abundance. The palm swamp and the low forest situated on the foothills of an inselberg, hosted different termite communities to the other sites. These two sites presented a singular physiognomy suggesting that forest type is an important factor influencing species composition. We found no correlation between termite species composition and distance between sites, highlighting that at the scale of our study (about 100 km), forest sites share a similar species pool.  相似文献   
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Glycosylation analysis of recombinant glycoproteins is of importance for the biopharmaceutical industry and the production of glycoprotein pharmaceuticals. A commercially available lectin array technology was evaluated for its ability to present a reproducible fingerprint of a recombinant CTLY4-IgG fusion glycoprotein expressed in large scale CHO-cell fermentation. The glycosylation prediction from the array was compared to traditional negative mode capillary LC-MS of released oligosaccharides. It was shown that both methods provide data that allow samples to be distinguished by their glycosylation pattern. This included information about sialylation, the presence of reducing terminal galactose β1-, terminal N-acetylglucosamine β1-, and antennary distribution. With both methods it was found that a general trend of increased sialylation was associated with an increase of the antenna and reduced amount of terminal galactose β1-, while N-acetylglucosamine β1- was less affected. LC-MS, but not the lectin array, provided valuable information about the sialic acid isoforms present, including N-acetylneuraminic acid, N-glycolylneuraminic acid and their O-acetylated versions. Detected small amounts of high-mannose structures by LC-MS correlated with the detection of the same epitope by the lectin array.  相似文献   
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