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A. V. Alesenko N. A. Babenko M. Yu. Pushkareva V. N. Nikitin 《Bulletin of experimental biology and medicine》1989,108(3):1246-1248
Institute of Chemical Physics, Academy of Sciences of the USSR, Moscow. A. M. Gor'kii Kharkov University. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 9, pp. 287–289, September, 1989. 相似文献
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Lifetime exposure to a soluble TGF-beta antagonist protects mice against metastasis without adverse side effects 总被引:14,自引:0,他引:14 下载免费PDF全文
Yang YA Dukhanina O Tang B Mamura M Letterio JJ MacGregor J Patel SC Khozin S Liu ZY Green J Anver MR Merlino G Wakefield LM 《The Journal of clinical investigation》2002,109(12):1607-1615
TGF-betas play diverse and complex roles in many biological processes. In tumorigenesis, they can function either as tumor suppressors or as pro-oncogenic factors, depending on the stage of the disease. We have developed transgenic mice expressing a TGF-beta antagonist of the soluble type II TGF-beta receptor:Fc fusion protein class, under the regulation of the mammary-selective MMTV-LTR promoter/enhancer. Biologically significant levels of antagonist were detectable in the serum and most tissues of this mouse line. The mice were resistant to the development of metastases at multiple organ sites when compared with wild-type controls, both in a tail vein metastasis assay using isogenic melanoma cells and in crosses with the MMTV-neu transgenic mouse model of metastatic breast cancer. Importantly, metastasis from endogenous mammary tumors was suppressed without any enhancement of primary tumorigenesis. Furthermore, aged transgenic mice did not exhibit the severe pathology characteristic of TGF-beta null mice, despite lifetime exposure to the antagonist. The data suggest that in vivo the antagonist may selectively neutralize the undesirable TGF-beta associated with metastasis, while sparing the regulatory roles of TGF-betas in normal tissues. Thus this soluble TGF-beta antagonist has potential for long-term clinical use in the prevention of metastasis. 相似文献
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Chen M Gavrilova O Zhao WQ Nguyen A Lorenzo J Shen L Nackers L Pack S Jou W Weinstein LS 《The Journal of clinical investigation》2005,115(11):3217-3227
The G protein G(s)alpha is essential for hormone-stimulated cAMP generation and is an important metabolic regulator. We investigated the role of liver G(s)-signaling pathways by developing mice with liver-specific G(s)alpha deficiency (LGsKO mice). LGsKO mice had increased liver weight and glycogen content and reduced adiposity, whereas survival, body weight, food intake, and metabolic rates at ambient temperature were unaffected. LGsKO mice had increased glucose tolerance with both increased glucose-stimulated insulin secretion and increased insulin sensitivity in liver and muscle. Fed LGsKO mice were hypoglycemic and hypoinsulinemic, with low expression of hepatic gluconeogenic enzymes and PPARgamma coactivator-1. However, LGsKO mice maintained normal fasting glucose and insulin levels, probably due to prolonged breakdown of glycogen stores and possibly increased extrahepatic gluconeogenesis. Lipid metabolism was unaffected in fed LGsKO mice, but fasted LGsKO mice had increased lipogenic and reduced lipid oxidation gene expression in liver and increased serum triglyceride and FFA levels. LGsKO mice had very high serum glucagon and glucagon-like peptide-1 levels and pancreatic alpha cell hyperplasia, probably secondary to hepatic glucagon resistance and/or chronic hypoglycemia. Our results define novel roles for hepatic G(s)-signaling pathways in glucose and lipid regulation, which may prove useful in designing new therapeutic targets for diabetes and obesity. 相似文献
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Fedor A. Platonov Kathrin Tyryshkin Dmitriy G. Tikhonov Tatyana S. Neustroyeva Tatyana M. Sivtseva Natalya V. Yakovleva Valerian P. Nikolaev Oksana G. Sidorova Sardana K. Kononova Lev G. Goldfarb Neil M. Renwick 《Neurogenetics》2016,17(3):179-185
Spinocerebellar ataxia type 1 (SCA1) is the major and likely the only type of autosomal dominant cerebellar ataxia in the Sakha (Yakut) people of Eastern Siberia. The prevalence rate of SCA1 has doubled over the past 21 years peaking at 46 cases per 100,000 rural population. The age at death correlates closely with the number of CAG triplet repeats in the mutant ATXN1 gene (r = ?0.81); most patients with low-medium (39–55) repeat numbers survived until the end of reproductive age. The number of CAG repeats expands in meiosis, particularly in paternal transmissions; the average total increase in intergenerational transmissions in our cohort was estimated at 1.6 CAG repeats. The fertility rates of heterozygous carriers of 39–55 CAG repeats in women were no different from those of the general Sakha population. Overall, the survival of mutation carriers through reproductive age, unaltered fertility rates, low childhood mortality in SCA1-affected families, and intergenerational transmission of increasing numbers of CAG repeats in the ATXN1 gene indicate that SCA1 in the Sakha population will be maintained at high prevalence levels. The low (0.19) Crow’s index of total selection intensity in our SCA1 cohort implies that this mutation is unlikely to be eliminated through natural selection alone. 相似文献
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Jenna B. Honeycutt Angela Wahl Caroline Baker Rae Ann Spagnuolo John Foster Oksana Zakharova Stephen Wietgrefe Carolina Caro-Vegas Victoria Madden Garrett Sharpe Ashley T. Haase Joseph J. Eron J. Victor Garcia 《The Journal of clinical investigation》2016,126(4):1353-1366
Macrophages have long been considered to contribute to HIV infection of the CNS; however, a recent study has contradicted this early work and suggests that myeloid cells are not an in vivo source of virus production. Here, we addressed the role of macrophages in HIV infection by first analyzing monocytes isolated from viremic patients and patients undergoing antiretroviral treatment. We were unable to find viral DNA or viral outgrowth in monocytes isolated from peripheral blood. To determine whether tissue macrophages are productively infected, we used 3 different but complementary humanized mouse models. Two of these models (bone marrow/liver/thymus [BLT] mice and T cell–only mice [ToM]) have been previously described, and the third model was generated by reconstituting immunodeficient mice with human CD34+ hematopoietic stem cells that were devoid of human T cells (myeloid-only mice [MoM]) to specifically evaluate HIV replication in this population. Using MoM, we demonstrated that macrophages can sustain HIV replication in the absence of T cells; HIV-infected macrophages are distributed in various tissues including the brain; replication-competent virus can be rescued ex vivo from infected macrophages; and infected macrophages can establish de novo infection. Together, these results demonstrate that macrophages represent a genuine target for HIV infection in vivo that can sustain and transmit infection. 相似文献
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Serologic screening of United States blood donors for Babesia microti using an investigational enzyme immunoassay 下载免费PDF全文
Andrew E. Levin Phillip C. Williamson Evan M. Bloch Joan Clifford Sherri Cyrus Beth H. Shaz Debra Kessler Jed Gorlin James L. Erwin Neil X. Krueger Greg V. Williams Oksana Penezina Sam R. Telford IV John A. Branda Peter J. Krause Gary P. Wormser Anna M. Schotthoefer Thomas R. Fritsche Michael P. Busch 《Transfusion》2016,56(7):1866-1874