10 research outputs found
Pathological changes in the liver of a senescence accelerated mouse strain (SAMP8): A mouse model for the study of liver diseases
Liver disease is characterized by fatty liver,
hepatitis, fibrosis and cirrhosis and is a major cause of
illness and death worldwide. The prevalence of liver
diseases highlights the need for animal models for
research on the mechanism of disease pathogenesis and
efficient and cost-effective treatments. Here we show
that a senescence-accelerated mouse strain (SAMP8
mice), displays severe liver pathology, which is not seen
in senescence-resistant mice (SAMR1). The livers of
SAMP8 mice show fatty degeneration, hepatocyte death,
fibrosis, cirrhotic changes, inflammatory mononuclear
cell infiltration and sporadic neoplastic changes. SAMP8
mice also show abnormal liver function tests:
significantly increased levels of alanine aminotransferase
(ALT) and aspartate aminotransferase (AST).
Furthermore, titers of murine leukemia virus are higher
in livers of SAMP8 than in those of SAMR1 mice. Our
observations suggest that SAMP8 mouse strain is a
valuable animal model for the study of liver diseases.
The possible mechanisms of liver damage in SAMP8
mice are also discussed
Multicriteria transformer asset management with maintenance and planning perspectives
Strategic asset management of transformer fleets in electrical power systems is a critical aspect for distribution utilities. In this study, an integrated framework for multicriteria asset management is presented. A multiobjective optimisation model is deployed, simultaneously minimising the maintenance costs and the predicted cost of unexpected failures, based on statistical estimates of failure probability and on the expected economic impact of failures. A multicriteria decision-support system is used for the selection of the recommended maintenance policy for a given time window. A criticality score for each transformer, which can assist planning engineers in defining replacement investments, is also provided. The application of the proposed framework is illustrated using the database of Brazilian power distribution utility CEMIG
Granulocyte-macrophage colony-stimulating factor and the immune system
Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multifunctional cytokine currently used for the reversal of neutropenia associated with cytotoxic chemotherapy, bone marrow and haemopoietic stem cell transplantation. GM-CSF also modulates the function of differentiated white blood cells. In the context of local inflammatory responses, GM-CSF stimulates macrophages for antimicrobial and antitumor effects. GM-CSF further enhances healing and repair by its actions on fibroblasts and epidermal cells. GM-CSF is the pivotal mediator of the maturation and function of dendritic cells, the most important cell type for the induction of primary T cell immune responses. GM-CSF may enhance antibody dependent cellular cytotoxicity (ADCC) in several cell types, and the generation and cytotoxicity of natural killer (NK) cells. On this basis, GM-CSF may be useful for inducing or augmenting antibody responses to antimicrobial vaccines, to enhance killing of intracellular microorganisms, to accelerate epidermal and mucosal wound healing, and to stimulate protective immunity against tumors
A review of the role of emerging environmental contaminants in the development of breast cancer in women
The incidence of breast cancer is on a rise worldwide; it is a disease having a complex etiology. Besides genetics, environmental and other lifestyle factors play a role in the development of the disease. There has been a keen interest in studying associations between breast cancer and exposures to emerging environmental chemicals, which mimic estrogens or influence estrogen levels and signaling in the human body. The common consequence of an endocrine disrupting chemical exposure is that it may have an impact on breast cancer etiology by stimulating formation as well as progression of breast cancer. Exposures to selected emerging environmental contaminants such as alkylphenols (APs), bisphenol A (BPA), parabens, perfluoroalkyl substances (PFASs), phthalates, polybrominated diphenyl ethers (PBDEs), synthetic musks and triclosan, and their probable role in breast cancer development are reviewed. Studies evaluated include the experimental in vitro and in vivo studies as well as human population based studies. In vitro and in vivo evidences indicate that a number of emerging environmental contaminants may play a role in the initiation and/or progression of breast cancer. Although exposures have been assessed in some human populations, breast and other cancer risks associated with these exposures are largely unknown. Efforts should be focussed on the evaluation of these environmental exposures in human populations and their interactions with each other and other genetic and lifestyle risk factors