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991.
Golubovskaya V Beviglia L Xu LH Earp HS Craven R Cance W 《The Journal of biological chemistry》2002,277(41):38978-38987
The focal adhesion kinase (FAK) and epidermal growth factor receptor (EGFR) are protein-tyrosine kinases that are overexpressed and activated in human breast cancer. To determine the role of EGFR and FAK survival signaling in breast cancer, EGFR was stably overexpressed in BT474 breast cancer cells, and each signaling pathway was specifically targeted for inhibition. FAK and EGFR constitutively co-immunoprecipitated in EGFR-overexpressing BT474 cells. In low EGFR-expressing BT474-pcDNA3 vector control cells, inhibition of FAK by the FAK C-terminal domain caused detachment and apoptosis via pathways involving activation of caspase-3 and -8, cleavage of poly(ADP-ribose) polymerase, and caspase-3-dependent degradation of AKT. This apoptosis could be rescued by the dominant-negative Fas-associated death domain, indicating involvement of the death receptor pathway. EGFR overexpression did not inhibit detachment induced by the FAK C-terminal domain, but did suppress apoptosis, activating AKT and ERK1/2 survival pathways and inhibiting cleavage of FAK, caspase-3 and -8, and poly(ADP-ribose) polymerase. Furthermore, this protective effect of EGFR signaling was reversed by EGFR kinase inhibition with AG1478. In addition, inhibition of FAK and EGFR in another breast cancer cell line (BT20) endogenously overexpressing these kinases also induced apoptosis via the same mechanism as in the EGFR-overexpressing BT474 cells. The results of this study indicate that dual inhibition of FAK and EGFR signaling pathways can cooperatively enhance apoptosis in breast cancers. 相似文献
992.
Merendino RA Di Rosa AE Di Pasquale G Minciullo PL Mangraviti C Costantino A Ruello A Gangemi S 《Mediators of inflammation》2002,11(4):265-267
Interleukin-18 (IL-18), a pro-inflammatory cytokine that plays an important role in the T-cell-helper type 1 response, is a new member of the family of cytokines produced in the brain. CD30 is a marker of T-cell-helper type 2 lymphocytes. We evaluated IL-18 and CD30 serum levels in 10 patients affected by moderate-severe depression (MSD). We demonstrated for the first time that serum IL-18 levels of MSD patients were significantly higher than those of healthy donors. On the contrary, no significant difference was found between serum CD30 levels of MSD patients compared with those of healthy donors. These data strengthen the hypothesis that MSD disease is associated with an inflammatory response, mainly T-cell-helper type 1, and suggest an important role for IL-18 in the pathophysiology of MSD. 相似文献
993.
Wocial L 《Bioethics forum》2002,18(1-2):15-23
Moral distress is a common occurrence for individuals involved in the care of critically ill infants. The ability to reason through difficult situations is often complicated by intensely emotional circumstances. Ethics consultation in the Neonatal Intensive Care Unit is a useful tool for caregivers and families who face moral problems. Understanding the responsibility of caregivers and parents to act as independent moral agents is an essential element in reducing moral distress and working collaboratively to resolve moral problems. 相似文献
994.
Fate map of the chicken neural plate at stage 4 总被引:4,自引:0,他引:4
Fernández-Garre P Rodríguez-Gallardo L Gallego-Díaz V Alvarez IS Puelles L 《Development (Cambridge, England)》2002,129(12):2807-2822
A detailed fate map was obtained for the early chick neural plate (stages 3d/4). Numerous overlapping plug grafts were performed upon New-cultured chick embryos, using fixable carboxyfluorescein diacetate succinimidyl ester to label donor chick tissue. The specimens were harvested 24 hours after grafting and reached in most cases stages 9-11 (early neural tube). The label was detected immunocytochemically in wholemounts, and cross-sections were later obtained. The positions of the graft-derived cells were classified first into sets of purely neural, purely non-neural and mixed grafts. Comparisons between these sets established the neural plate boundary at stages 3d/4. Further analysis categorized graft contributions to anteroposterior and dorsoventral subdivisions of the early neural tube, including data on the floor plate and the eye field. The rostral boundary of the neural plate was contained within the earliest expression domain of the Ganf gene, and the overall shape of the neural plate was contrasted and discussed with regard to the expression patterns of the genes Plato, Sox2, Otx2 and Dlx5 (and others reported in the literature) at stages 3d/4. 相似文献
995.
In acetate buffer, pH 4, at room temperature, nitrite ions can mediate an unusual decarboxylative conjugation of caffeic acid with glutathione leading to novel isomeric 2-(3,4-dihydroxyphenyl)-2-S-glutathionylacetaldehyde oximes. These results hint at a possible role of endogenous and/or dietary glutathione in the mechanisms by which caffeic acid can affect the burden of carcinogenic N-nitroso compounds in the digestive tract. 相似文献
996.
997.
Aqueous and solid complexes of iron(III) with hyaluronic acid. Potentiometric titrations and infrared spectroscopy studies 总被引:1,自引:0,他引:1
Mercê AL Marques Carrera LC Santos Romanholi LK Lobo Recio MA 《Journal of inorganic biochemistry》2002,89(3-4):212-218
The coordination of iron(III) ion to hyaluronic acid (Hyal) in aqueous solutions and solid state was accomplished by potentiometric titrations and infrared spectroscopy. The potentiometric titration studies provided the binding constants for the complexes found in the systems and the speciation of these species according to the variation of pH values. The complexes found presented a complexing ability through both the chelating moieties of Hyal (via the N-glucosamine and D-glucoronic acid), showing no special preference for either one while in solid state, but when in aqueous solution the complexation via the N-glucosamine moiety was the preferred, forming two complexed species, ML and ML(2) (log K(ML)=8.2 and log K(ML2)=7.9). The presence of a mu-oxo complex via the D-glucoronic acid was also detected in both aqueous (log K=6.7) and solid states via the N-glucosamine and D-glucoronic acid simultaneously linked to two Hyal chains. A structure for this latter complex was suggested. The results indicated that these complexes could be used in eliminating the excess iron(III) in living organisms. 相似文献
998.
Toma S Colucci L Scarabelli L Scaramuccia A Emionite L Betta PG Mutti L 《Journal of cellular physiology》2002,193(1):37-41
Malignant mesothelioma (MM) still remains a therapeutic and diagnostic problem to which new therapeutic perspectives are being continuously tried and tested. Three different primary cultures (MMGe-1, MES MM 98, and MES 1) and one immortalized cell line (MSTO 211 H) of human MM were studied in order to evaluate the HER-2/neu expression. Three out of four cell lines showed a different level of c-erbB-2 expression, the highest being detected on the MSTO 211 H cell line (fibroblastic phenotype), whereas MMGe-1 resulted negative. The effect of the anti-HER-2/neu antibody (Trastuzumab) alone, and in combination with cisplatin (CDDP) at different doses (ranging from 0.1 to 100 microg/ml), was studied on all the c-erB-2 positive cell lines. Trastuzumab was able to inhibit cell proliferation in a time-dependent manner, with growth inhibition also obtained at low concentrations (0.1-1 microg/ml). Combined treatment with Trastuzumab (10 microg/ml) and CDDP (1 microg/ml) showed synergism. Our results were encouraging, and suggest a rationale for further investigations in a clinical setting. 相似文献
999.
CD80+Gr-1+ myeloid cells inhibit development of antifungal Th1 immunity in mice with candidiasis 总被引:5,自引:0,他引:5
Mencacci A Montagnoli C Bacci A Cenci E Pitzurra L Spreca A Kopf M Sharpe AH Romani L 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(6):3180-3190
To find out whether polymorphonuclear neutrophils (PMN), abundantly recruited in disseminated Candida albicans infection, could directly affect the activation of Th cells we addressed the issues as to whether murine PMN, like their human counterparts, express costimulatory molecules and the functional consequence of this expression in terms of antifungal immune resistance. To this purpose, we assessed 1) the expression of CD80 (B7-1) and CD86 (B7-2) molecules on peripheral, splenic, and inflammatory murine Gr-1+ PMN; 2) its modulation upon interaction with C. albicans in vitro, in vivo, and in human PMN; 3) the effect of Candida exposure on the ability of murine PMN to affect CD4+ Th1 cell proliferation and cytokine production; and 4) the mechanism responsible for this effect. Murine PMN constitutively expressed CD80 molecules on both the surface and intracellularly; however, in both murine and human PMN, CD80 expression was differentially modulated upon interaction with Candida yeasts or hyphae in vitro as well as in infected mice. The expression of the CD86 molecule was neither constitutive nor inducible upon exposure to the fungus. In vitro, Gr-1+ PMN were found to inhibit the activation of IFN-gamma-producing CD4+ T cells and to induce apoptosis through a CD80/CD28-dependent mechanism. A population of CD80+Gr-1+ myeloid cells was found to be expanded in conventional as well as in bone marrow-transplanted mice with disseminated candidiasis, but its depletion increased the IFN-gamma-mediated antifungal resistance. These data indicate that alternatively activated PMN expressing CD80 may adversely affect Th1-dependent resistance in fungal infections. 相似文献
1000.
Pinto-da-Silva LH Camurate M Costa KA Oliveira SM da Cunha-e-Silva NL Saraiva EM 《International journal for parasitology》2002,32(11):1371-1377
In this study we characterised metacyclogenesis in axenic culture of Leishmania (Viannia) braziliensis, the causative agent of mucocutaneous leishmaniasis in the New World. Metacyclogenesis of other species of Leishmania has been shown by morphological changes as well as molecular modifications in the lipophosphoglycan, the major cell surface glycoconjugate of the promastigotes. In order to obtain metacyclic forms of L. braziliensis we tested a panel of different lectins. Our results showed that Bauhinia purpurea lectin facilitated the purification of metacyclic promastigotes from stationary-phase culture by negative selection. The B. purpurea non-agglutinated promastigotes had a slender short cell body and long flagella, typical of metacyclic morphology. The ultrastructural analysis showed that B. purpurea non-agglutinated promastigotes have a dense and thicker glycocalyx. They are resistant to complement lysis, and highly infective for macrophage in vitro and hamsters in vivo. Contrary to procyclic promastigotes, B. purpurea non-agglutinated forms were poorly recognised by sand fly gut epithelial cells. These results suggest that the B. purpurea non-agglutinated promastigotes are the metacyclic forms of L. braziliensis. 相似文献