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91.
Orlistat, an inhibitor of fatty acid synthase (FASN), acts as an antitumor agent by blocking de novo fatty acid synthesis of tumor cells. Although, myelopoiesis also depends on de novo fatty acid synthesis, the effect of orlistat on differentiation of macrophages, which play a central role in host’s antitumor defence, remains unexplored in a tumor-bearing host. Therefore, the present investigation was undertaken to examine the effect of orlistat administration on macrophage differentiation in a T cell lymphoma bearing host. Administration of orlistat (240 mg/kg/day/mice) to tumor-bearing mice resulted in a decline of tumor load accompanied by an augmentation of bone marrow cellularity and survival of bone marrow cells (BMC). The expression of apoptosis regulatory caspase-3, Bax and Bcl2 was modulated in the BMC of orlistat-administered tumor-bearing mice. Orlistat administration also resulted in an increase in serum level of IFN-γ along with decreased TGF-β and IL-10. BMC of orlistat-administered tumor-bearing mice showed augmented differentiation into macrophages accompanied by enhanced expression of macrophage colony stimulating factor (M-CSF) and its receptor (M-CSFR). The macrophages differentiated from BMC of orlistat-administered mice showed characteristic features of M1 macrophage phenotype confirmed by expression of CD11c, TLR-2, generation of reactive oxygen species, phagocytosis, tumor cell cytotoxicity, production of IL-1,TNF-α and nitric oxide. These novel findings indicate that orlistat could be useful to support myelopoesis in a tumor-bearing host.  相似文献   
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Interleukin-10 (IL-10) is an anti-inflammatory cytokine with important immunoregulatory functions. It is primarily secreted by antigen-presenting cells such as activated T-cells, monocytes, B-cells and macrophages. In biologically functional form, it exists as a homodimer that binds to tetrameric heterodimer IL-10 receptor and induces downstream signaling. IL-10 is associated with survival, proliferation and anti-apoptotic activities of various cancers such as Burkitt lymphoma, non-Hodgkins lymphoma and non-small scell lung cancer. In addition, it plays a central role in survival and persistence of intracellular pathogens such as Leishmania donovani, Mycobacterium tuberculosis and Trypanosoma cruzi inside the host. The signaling mechanisms of IL-10 cytokine are not well explored and a well annotated pathway map has been lacking. To this end, we developed a pathway resource by manually annotating the IL-10 induced signaling molecules derived from literature. The reactions were categorized under molecular associations, activation/inhibition, catalysis, transport and gene regulation. In all, 37 molecules and 76 reactions were annotated. The IL-10 signaling pathway can be freely accessed through NetPath, a resource of signal transduction pathways previously developed by our group.  相似文献   
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Purified polyhedron proteins and purified, ultrasonicated virions of four nuclear polyhedrosis viruses (NPVs), separable into two morphologic groups of singly and multiply embedded virion types (SEVs and MEVs), were investigated by immunodiffusion and immunoelectrophoresis. The four viruses were Pseudoplusia includens SEV, Trichoplusia ni SEV, T. ni MEV, and Autographa californica MEV. In immunodiffusion, SEV polyhedron proteins formed two precipitin bands with antiserum to SEV polyhedron proteins, while MEV polyhedron proteins formed only one. All four proteins formed one precipitin band with antiserum to MEV polyhedron protein, with a spur between SEV and MEV proteins. In immunoelectrophoresis, mobilities of SEV proteins were significantly different from those of MEVs. Precipitin arc patterns were similar to those in immunodiffusion when electrophoresis was carried out at 4 C; at room temperature, a single arc of precipitation formed with all four proteins. SEV virions formed five possibly identical precipitin bands in immunodiffusion with antiserum to SEV virions. MEV virions formed three possibly identical precipitin bands when reacted with antiserum to MEV virions. Little or no cross-reactions were observed between SEV and MEV virions or between virions and polyhedron proteins. In immunoelectrophoresis, SEV virions formed three precipitin arcs in reactions with SEV antisera and none with MEV antisera; MEV virions formed two arcs with MEV antisera and none with SEV antisera. When antisera were subjected to electrophoresis, five arcs were formed by SEVs and three by MEVs in homologous systems, and none were formed in heterologous systems.  相似文献   
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Psoriasis is a polygenic chronic skin condition, associated with many systemic disorders. Though it is most studied dermatological condition, molecular mechanism leading to its pathogenesis is still unclear. An insight into its proteome may help unrevealing some biomarkers and therapeutic targets. In this study, we carried out mass spectrometry based quantitative proteomic analysis of serum from psoriasis patients by employing Tandem Mass Tags (TMT) approach. We identified 861,887 MS/MS spectra corresponding to 493 proteins. These dysregulated proteins were further classified by Gene Ontology and protein-protein interaction of dys-regulated proteins revealed networks in psoriasis patients.  相似文献   
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International Journal of Peptide Research and Therapeutics - Escherichia coli is one of the simplest hosts which is widely being used to express heterologous proteins. However, without appropriate...  相似文献   
99.
The search for genetic causes involved in alcohol dependence/response has been challenging. Understanding the mechanisms of action and interaction of the genes implicated in alcohol response is a key towards understanding the problem. Sixty-nine ethanol responsive genes were used in a detailed genome-wide examination to study their neuro-metabolomics. These genes displayed very close interactions among themselves with over 400 regulation events and 100 expression events contributing to 15 different cell processes including cell signaling, transport and proliferation. Acute ethanol produces a global effect on the neuro-metabolome. Ethanol alone was found to interact with over 1000 genes and cell events. The study revealed that the ethanol responsive genes directly regulate and are themselves regulated by the activity of other proteins and cell processes. We propose a pathway involving nine interacting ethanol responsive genes, which may determine differential ethanol effects in the brain in vivo.  相似文献   
100.
Transgene copy number is an important criterion for determining the utility of transgenic events. Single copy integration events are highly desirable when the objective is to produce marker free plants through segregation or when it is necessary to introgress different transgenes into commercial cultivars from different transgenic events. In contrast multi-copy events are advocated by several authors for higher expression of the transgene. Till recently, it was thought that employment of the particle gun for transformation results in the production of a high proportion of multi-copy events often with complex integration pattern when compared to Agrobacterium-mediated transformation. However, it has been demonstrated that usage of cassette DNA for bombardment in place of whole plasmids would result in simple insertion pattern of the transgenes. While investigating the effect of varying the cassette DNA amount on stable transformation, the frequency of occurrence of low copy events was observed to increase when lower doses of cassette DNA was employed for bombardment. Large scale experimentation with rigorous statistical analysis performed to verify the above observations employing Helium gun and the Electric discharge gun for gene delivery confirmed the above observations. Helium gun experiments involving production of more than 1,600 corn events consistently yielded single copy events at higher frequencies at lower cassette DNA load (46% at 2.5 ng/shot) as compared to higher cassette DNA load (29% at 25 ng/shot) across 18 independent experiments. Results were nearly identical with the Electric discharge particle gun device where single copy events were recovered at frequencies of 54% at 2.5 ng cassettes DNA per shot as compared to 18% at 25 ng cassette DNA per shot. The transformation frequency declined from 41 to 34% (Helium gun) and from 48 to 31% (Electric discharge gun) with reduction in cassette DNA quantity from 25 to 2.5 ng per shot. This reduction in the transformation frequency is more than compensated by the savings in time and effort involved in the production and screening of events if the desired outcome is single copy events. These results demonstrate the flexibility of the particle gun method for controlling the frequency of production of either low copy or high copy events by altering the quantity of cassette DNA used for bombardment. The transgene expression levels over generations in relation to its integration need further investigations.  相似文献   
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