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Recent investigations have showed that the functional thermogenic adipocytes are present in both infants and adult humans. Accumulating evidence suggests that the coexistence of classical and inducible brown (brite) adipocytes in humans at adulthood and these adipocytes function to generate heat from energy resulting in reducing body fat and improving glucose metabolism. Human thermogenic adipocytes can be differentiated in vitro from stem cells, cell lines, or adipose stromal vascular fraction. Pre-activated human brite adipocytes in vitro can maintain their thermogenic function in normal or obese immunodeficient mice; therefore, they improve glucose homeostasis and reduce fat mass in obese animals. These key findings have opened a new door to use in vitro thermogenic adipocytes as a cell therapy to prevent obesity and related disorders. Thus, this paper intends to highlight our knowledge in aspects of in vitro human brite/brown adipocytes for the further studies.  相似文献   
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Intermediary metabolism, a dominant research area before the emergence of molecular biology, is attracting renewed interest for fundamental and applied reasons as documented here. Nonetheless, the field may appear to be a thicket precluding entry to all but the most determined. Here we present a metabolic overview that makes this important and fascinating area accessible to a broad range of the molecular biological and biotechnological communities that are being attracted to biological problems crying out for metabolic solutions. This is accomplished by identifying seven key concepts, a so-called metabolic central dogma, that provide a core understanding analogous to the “Central Dogma of Molecular Biology” which focused upon maintenance and flow of genetic information.  相似文献   
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We investigated the basic technology of cell culture conditions for production of useful substances such as cytokines, and related proteins produced by Namalwa cells. Namalwa cells (Klein, 1972), human B lymphoblastoid cells, were used for large scale production of alpha-interferon (Klein, 1979). Namalwa KJM-1, a subline of Namalwa cells, adapted to serum- and albumin-free medium, can grow at a high density above 1 × 107 cells/ml in suspension mode by the use of a perfusion culture system, Biofermenter?, containing a cone-type cell-sedimentation column as cell separator (Sato, 1983).Several kinds of cytokine cDNA can be introduced and expressed in Namalwa KJM-1 cells (Miyaji, 1990a,b,c). Some of these were produced in large quantities by use of a gene amplification method with dhfr (Miyaji, 1990c), even though the Namalwa KJM-1 cells contained endogenous dhfr genes. For stable production of the target protein, Namalwa KJM-1 cells are very useful host cells, because they have no effective endogenous protease activity in the conditioned medium.Using Biofermenter with micro-silicone fibers and a dialysis system, the specific productivity of the target proteins was not depressed at a high cell density.  相似文献   
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The new EU-regulations on organic farming (1804/1999) are also influencing the animal welfare. A lot of positive regulations is to find, but also regulations that seen to mind more about the general public and customer and their view on organic farming, than the health and welfare of the animals.The paper specially focus on the impact of the regulations and the recommendations that phytotherapeutic essences and homeopathic products take precedence over the so called chemically-synthesised allopatic veterinary medical products, and that the use of the same is prohibited for preventive treatments. Key questions here are the lack of scientific evidence concerning homeopathy in animals, and that Swedish veterinarians are not allowed to work with homeopathy.Differences in interpretation of the regulations between animal owners and veterinarians will also be discussed. What is a disease that needs treatment? Who is to decide about the treatment? Parasitic infections are discussed as an illustrative example.Other consequences of the regulations concerning the animal welfare are problems in certain geographical zones, for instance subarctic areas where necessary crops are impossible to grow.Animal transports and splitting mother-offspring are briefly discussed as future problems to be handled in the regulations, and the paper ends by presenting the need of regulated herd health control programs in organic husbandry, which can detect and focus on welfare and production problems. The organic movement is not static, and must not be so.  相似文献   
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