934 resultados para Anti-ADN topoisomérase I
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Thesis (Master's)--University of Washington, 2016-06
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Thesis (Master's)--University of Washington, 2016-06
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The role of growth hormone (GH) in embryonic growth is controversial, yet preimplantation embryos express GH, insulin-like growth factor I (IGF-I) and their receptors. In this study, addition of bovine GH doubled the proportion of two-cell embryos forming blastocysts and increased by about 25% the number of cells in those blastocysts with a concentration-response curve showing maximal activity at 1 pg bovine GH ml(-1), with decreasing activity at higher and lower concentrations. GH increased the number of cells in the trophectoderm by 25%, but did not affect the inner cell mass of blastocysts. Inhibition of cell proliferation by anti-GH antiserum indicated that GH is a potent autocrine or paracrine regulator of the number of trophectoderm cells in vivo. Type 1 IGF receptors (IGF1R) were localized to cytoplasmic vesicles and plasma membrane in the apical domains of uncompacted and compacted eight-cell embryos, but were predominantly apparent in cytoplasmic vesicles of the trophectoderm cells of the blastocyst, similar to GH receptors. Studies using alphaIR3 antiserum which blocks ligand activation of IGF1R, showed that IGF1R participate in the autocrine or paracrine regulation of the number of cells in the inner cell mass by an endogenous IGF-I-IGF1R pathway. However, alphaIR3 did not affect GH stimulation of the number of trophectoderm cells. Therefore, CH does not use secondary actions via embryonic IGF-I to modify the number of blastocyst cells. This result indicates that GH and IGF-I act independently. GH may selectively regulate the number of trophectoderm cells and thus implantation and placental growth. Embryonic GH may act in concert with IGF-I, which stimulates proliferation in the inner cell mass, to optimize blastocyst development.
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Advanced metastatic melanoma is incurable by standard treatments, but occasionally responds to immunotherapy. Recent trials using dendritic cells (DC) as a cellular adjuvant have concentrated on defined peptides as the source of antigens, and rely on foreign proteins as a source of help to generate a cell-mediated immune response. This approach limits patient accrual, because currently defined, non-mutated epitopes are restricted by a small number of human leucocyte antigens. It also fails to take advantage of mutated epitopes peculiar to the patient's own tumour, and of CD4(+) T lymphocytes as potential effectors of anti-tumour immunity. We therefore sought to determine whether a fully autologous DC vaccine is feasible, and of therapeutic benefit. Patients with American Joint Cancer Committee stage IV melanoma were treated with a fully autologous immunotherapy consisting of monocyte-derived DC, matured after culture with irradiated tumour cells. Of 19 patients enrolled into the trial, sufficient tumour was available to make treatments for 17. Of these, 12 received a complete priming phase of six cycles of either 0.9X10(6) or 5X10(6) DC/intradermal injection, at 2-weekly intervals. Where possible, treatment continued with the lower dose at 6-weekly intervals. The remaining five patients could not complete priming, due to progressive disease. Three of the 12 patients who completed priming have durable complete responses (average duration 3 5 months +), three had partial responses, and the remaining six had progressive disease (WHO criteria). Disease regression was not correlated with dose or with the development of delayed type hypersensitivity responses to intradermal challenge with irradiated, autologous tumour. However, plasma S-100B levels prior to the commencement of treatment correlated with objective clinical response (P = 0.05) and survival (log rank P < 0.001). The treatment had minimal side-effects and was well tolerated by all patients. Mature, monocyte-derived DC preparations exposed to appropriate tumour antigen sources can be reliably produced for patients with advanced metastatic melanoma, and in a subset of those patients with lower volume disease their repeated administration results in durable complete responses.
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[GRAPHICS] The major cuticular hydrocarbons from the cane beetle species Antitrogus parvulus are 4,6,8,10,16-penta- and 4,6,8,10,16,18-hexamethyldocosanes, I and 2, respectively. Stereoisomers of 2,4,6,8-tetramethylundecanal of established relative stereochemistry were derived from 2,4,6-trimethylphenol and were then coupled with appropriate methyl-substituted phosphoranes 62 and 25 to furnish alkenes, which on reduction provided diastereomers of I and 2, respectively. Capillary gas chromatography, mass spectrometry, and high resolution C-13 NMR spectroscopy confirmed 1 as either 84a or 84b and 2 as either 15a or 15b. The novelty of these structures and their relative stereochemistry is briefly related to polyketide assembly.
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The mechanisms responsible for the immunosuppression associated with sepsis or some chronic blood infections remain poorly understood. Here we show that infection with a malaria parasite (Plasmodium berghei) or simple systemic exposure to bacterial or viral Toll-like receptor ligands inhibited cross-priming. Reduced cross-priming was a consequence of downregulation of cross-presentation by activated dendritic cells due to systemic activation that did not otherwise globally inhibit T cell proliferation. Although activated dendritic cells retained their capacity to present viral antigens via the endogenous major histocompatibility complex class I processing pathway, antiviral responses were greatly impaired in mice exposed to Toll-like receptor ligands. This is consistent with a key function for cross-presentation in antiviral immunity and helps explain the immunosuppressive effects of systemic infection. Moreover, inhibition of cross-presentation was overcome by injection of dendritic cells bearing antigen, which provides a new strategy for generating immunity during immunosuppressive blood infections.
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Arsenic trioxide appears to be effective in the treatment of pro-myelocytic leukaemia. The substituted phenylarsen(III)oxides are highly polar, they have a high tendency to undergo oxidation to As (V) and to form oligomers, to prevent this we protected the As-(OH)2 group as cyclic dithiaarsanes. To increase the compound's biological stability and passive diffusion we conjugated the compound of interest with lipoamino acids (Laas). Alternatively, we further conjugated the dithiaarsane derivative with a carbohydrate to utilize active transport systems and to target compound. We investigated two novel glyco-lipid arsenicals (III) (compounds 9 and 11) for their ability to initiate MCF-7 breast cancer cell death and characterized the mechanism by which death was initiated. A significant decrease in MCF-7 cell proliferation was observed using 1 μM and 10 μM compound (11) and 10 μM of compound (9). Treatment with compound (11) triggered apoptosis of MFC-7 cells while compound (9) induced inhibition of cellular proliferation was not via rapid induction of apoptosis and more likely reflected necrosis and/ or alterations in the cell cycle. Differences in the anti-proliferative potency of the two compounds indicate that structural modifications influence effectiveness. © 2006 Bentham Science Publishers Ltd.
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Perceptions of America as a powerful but malevolent nation decrease its security. On the basis of measures derived from the stereotype content model (SCM) and image theory (IT), 5,000 college students in I I nations indicated their perceptions of the personality traits of, intentions of, and emotional reactions to the United States as well as their reactions to relevant world events (e.g., 9/11). The United States was generally perceived as competent but cold and arrogant. Although participants distinguished between the United States' government and its citizens, differences were small. Consistent with the SCM and IT, viewing the United States as intent on domination predicted perceptions of lack of warmth and of arrogance but not of competence and status. The discussion addresses implications for terrorist recruitment and ally support.
Why are consumers with heart failure still receiving non-steroidal anti-inflammatory drugs (NSAIDS)?
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In this article about ‘For Better or Worse? Lesbian and Gay Marriage’ (Feminism & Psychology, 14[1]) we focus on the contributions to the special feature, the commentaries provided by Ellen Lewin (2004), Sheila Jeffreys (2004) and Sue Wise and Liz Stanley (2004), and on wider debates about lesbian and gay marriage and partnership recognition. We agree that ‘there is a lot of confusion/assumptions made about what “it” (i.e. “marriage”) is’ (Wise and Stanley, 2004: 333). Thus, when talking about same-sex partnership recognition we are concerned with civil marriage (or civil union, or civil partnership), and not religious marriage. Our emphasis is on the public not on the private sphere; we are less interested with the personal aspects of relationships (such as intimacy or commitment) than with their public function in, for instance, obtaining ‘rights and responsibilities’.
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1. S-adenosyl-L-methionine (SAMe) had no effect on cytochrome C reduction by superoxide generated from xanthine oxidase except at high concentrations. This was due to direct inhibition of the enzyme. 2. SAMe inhibited the neutrophil respiratory burst , measured by luminol enhanced chemiluminescence, to FMLP and zymosan A but not to PMA. 3. Adenosine and methylthioadenosine (MTA) inhibited the respiratory burst elicited by FMLP. 4. SAMe inhibited the phagocytosis of latex particles by neutrophils at high concentrations but methionine and S-adenosyl L-homocysteine had no effect. 5. Treatment with SAMe had no effect on cell infiltration or PGE2 production in 6-day air pouches. 6. Treatment with SAMe at the optimum dose of 50mg/kg inhibited the early phases of carrageenan induced rat hind paw inflammation but had a lesser effect on the secondary response. The antiinflammatory effect was sustained after inhibiton of polyamine synthesis. 7. SAMe increased liver putrescine levels in the presence and absence of inflammation Spermidine levels were increased in the presence of inflammation but spermine levels were unaffected by any of the treatments. 8. MT A and adenosine increased liver putrescine and spermidine levels 9. Treatment with SAMe had no effect on the polyamine status of blood. lO.Treatment with SAMe had no effect on the levels of glutathione in liver or blood. 11.SAMe and MTA inhibited histamine and platelet-activating factor (PAF) induced hind paw inflammation but had no effect on inflammation induced by dextran, zymosan, compound 48/80, 5-hydroxytryptamine, arachidonic acid or glucose oxidase. MTA was more effective than SAMe. 12. PAP-induced rat hind paw inflammation was inhibited by isoprenaline and verapamil. Combinations of these drugs with SAMe or MT A had no further enhancement of effect. 13. Incubation of rat PMNLs with [14c ] SAMe increased the intracellular levels of S-adenosyl-L-homocysteine in a dose dependent manner, but had no effect on the intracellular levels of SAMe, adenosine or MT A. 14. Pharmacokinetic studies of plasma SAMe following a single dose of the drug (50mg/kg) i.p. demonstrated that SAMe is rapidly absorbed and metabolised
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We have evaluated the cytotoxicity of a series of novel anti-tubercular 2-pyridyl carboxamidrazones through incubation with human mononuclear leucocytes (MNL), with and without a rat microsomal metabolising system. Isoniazid (INH), the closest structurally related agent, was used as a positive control. Incubation of the 3-benzyloxy-benzylidene, dimethylpropyl-benzylidene and 4-phenyl-benzylidene with MNL showed no significant toxicity in comparison with either INH or DMSO vehicle control. However, the 4-N,N-dimethylamino-1-naphthylidene derivative exerted more than sevenfold greater toxicity compared with INH, while the 4-N,N-dimethylamino-1-naphthylidene, 2-benzyloxy-3-methoxy-benzylidene, 2-t-butylthio-benzylidene and 4-i-propyl-benzylidene derivatives showed toxicity which ranged from five to fourfold that of INH. In the presence of either rat microsomes with or without NADPH, the 3-benzyloxy-benzylidene, dimethylpropyl-benzylidene and 4-phenyl-benzylidene derivatives showed no metabolically-mediated cytotoxicity. The latter two derivatives showed a combination of low toxicity and considerable efficacy against Mycobacteria tuberculosis in vitro and show promise for future development. © 2001 Elsevier Science B.V.
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Cells dying by apoptosis are normally cleared by phagocytes through mechanisms that can suppress inflammation and immunity. Molecules of the innate immune system, the pattern recognition receptors (PRRs), are able to interact not only with conserved structures on microbes (pathogen-associated molecular patterns, PAMPs) but also with ligands displayed by apoptotic cells. We reasoned that PRRs might therefore interact with structures on apoptotic cells-apoptotic cell-associated molecular patterns (ACAMPs)-that are analogous to PAMPs. Here we show that certain monoclonal antibodies raised against the prototypic PAMP, lipopolysaccharide (LPS), can crossreact with apoptotic cells. We demonstrate that one such antibody interacts with a constitutively expressed intracellular protein, laminin-binding protein, which translocates to the cell surface during apoptosis and can interact with cells expressing the prototypic PRR, mCD14 as well as with CD14-negative cells. Anti-LPS cross reactive epitopes on apoptotic cells colocalised with annexin V-and C1q-binding sites on vesicular regions of apoptotic cell surfaces and were released associated with apoptotic cell-derived microvesicles (MVs). These results confirm that apoptotic cells and microbes can interact with the immune system through common elements and suggest that anti-PAMP antibodies could be used strategically to characterise novel ACAMPs associated not only with apoptotic cells but also with derived MVs. © 2013 Macmillan Publishers Limited All rights reserved.