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Judit Telegdi 《Materials》2020,13(22)
The review will first discuss shortly the phenomenon of corrosion and enroll some general possibilities to decrease the rate of this deterioration. The stress will be laid upon the presentation of anticorrosive self-assembled molecular (SAM) layers as well as on the preparation technology that is a simple technique, does not need any special device, and can be applied on different solids (metals or non-metals) alone or in combination. The paper groups the chemicals (mainly amphiphiles) that can develop nanolayers on different pure or oxidized metal surfaces. The history of the self-assembled molecular layer will be discussed from the beginning of the first application up to now. Not only the conditions of the nanofilm preparation as well as their characterization will be discussed, but the methods that can evaluate the corrosion-inhibiting efficiency of the SAM layers under a corrosive environment will be demonstrated as well. 相似文献
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Control of T helper 2 cell function and allergic airway inflammation by PKCzeta 总被引:2,自引:0,他引:2 下载免费PDF全文
Martin P Villares R Rodriguez-Mascarenhas S Zaballos A Leitges M Kovac J Sizing I Rennert P Márquez G Martínez-A C Diaz-Meco MT Moscat J 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(28):9866-9871
Asthma is a disease of chronic airway inflammation in which T helper (Th) 2 cells play a critical role. The molecular mechanisms controlling Th2 differentiation and function are of paramount importance in biology and immunology. PKCzeta has been implicated in the regulation of apoptosis and NF-kappaB, as well as in the control of T-dependent responses, although no defects were detected in na?ve T cells from PKCzeta-/- mice. Here, we report that PKCzeta is critical for IL-4 signaling and Th2 differentiation. Thus, PKCzeta levels are increased during Th2 differentiation, but not Th1 differentiation, of CD4+ T cells, and the loss of PKCzeta impairs the secretion of Th2 cytokines in vitro and in vivo, as well as the nuclear translocation and tyrosine phosphorylation of Stat6 and Jak1 activation, essential downstream targets of IL-4 signaling. Moreover, PKCzeta-/- mice display dramatic inhibition of ovalbumin-induced allergic airway disease, strongly suggesting that PKCzeta can be a therapeutic target in asthma. 相似文献
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Sylvia Vogl Paolo Picker Judit Mihaly-Bison Nanang Fakhrudin Atanas G. Atanasov Elke H. Heiss Christoph Wawrosch Gottfried Reznicek Verena M. Dirsch Johannes Saukel Brigitte Kopp 《Journal of ethnopharmacology》2013
Ethnopharmacological relevance
In Austria, like in most Western countries, knowledge about traditional medicinal plants is becoming scarce. Searching the literature concerning Austria's ethnomedicine reveals its scant scientific exploration.Aiming to substantiate the potential of medicinal plants traditionally used in Austria, 63 plant species or genera with claimed anti-inflammatory properties listed in the VOLKSMED database were assessed for their in vitro anti-inflammatory activity.Material and methods
71 herbal drugs from 63 plant species or genera were extracted using solvents of varying polarities and subsequently depleted from the bulk constituents, chlorophylls and tannins to avoid possible interferences with the assays. The obtained 257 extracts were assessed for their in vitro anti-inflammatory activity. The expression of the inflammatory mediators E-selectin and interleukin-8 (IL-8), induced by the inflammatory stimuli tumor necrosis factor alpha (TNF-α) and the bacterial product lipopolysaccharide (LPS) was measured in endothelial cells. The potential of the extracts to activate the nuclear factors PPARα and PPARγ and to inhibit TNF-α-induced activation of the nuclear factor-kappa B (NF-κB) in HEK293 cells was determined by luciferase reporter gene assays.Results
In total, extracts from 67 of the 71 assessed herbal drugs revealed anti-inflammatory activity in the applied in vitro test systems. Thereby, 30 could downregulate E-selectin or IL-8 gene expression, 28 were strong activators of PPARα or PPARγ (inducing activation of more than 2-fold at a concentration of 10 µg/mL) and 21 evoked a strong inhibition of NF-κB (inhibition of more than 80% at 10 µg/mL).Conclusion
Our research supports the efficacy of herbal drugs reported in Austrian folk medicine used for ailments associated with inflammatory processes. Hence, an ethnopharmacological screening approach is a useful tool for the discovery of new drug leads. 相似文献57.
Csoma E Bácsi A Liu X Szabó J Ebbesen P Beck Z Kónya J Andirkó I Nagy E Tóth FD 《Journal of medical virology》2002,67(1):67-87
Human herpesvirus 6 (HHV-6) and human immunodeficiency virus type 1 (HIV-1) may interact during transplacental transmission of HIV-1. The placental syncytiotrophoblast layer serves as the first line of defense of the fetus against viruses. Patterns of replication of HHV-6 variant A (HHV-6A) and HIV-1 were analyzed in singly and dually infected human term syncytiotrophoblast cells cultured in vitro. For this purpose, the GS strain of HHV-6A and the Ba-L and IIIB strains of HIV-1 were used. HHV-6A replication was restricted at the level of early gene products in singly infected syncytiotrophoblasts, whereas no viral protein expression was found in cells infected with HIV-1 alone. Coinfection of syncytiotrophoblast cells with HHV-6A and HIV-1 resulted in production of infectious HIV-1. In contrast, no enhancement of HHV-6A expression was observed in cell cultures infected with both viruses. Uninfected syncytiotrophoblast cells were found to express CXCR4 and CCR3 but not CD4 or CCR5 receptors. Infection of syncytiotrophoblasts with HHV-6A did not induce CD4 expression and had no influence on chemokine receptor expression. Activation of HIV-1 from latency in coinfected cells was mediated by the immediate-early (IE)-A and IE-B gene products of HHV-6A. Open reading frames U86 and U89 of the IE-A region were able to activate HIV-1 replication in a synergistic manner. The data suggest that in vivo double infection of syncytiotrophoblast cells with HHV-6A and HIV-1 could contribute to the transplacental transmission of HIV-1 but not HHV-6A. 相似文献
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Kolev K Tenekedjiev K Ajtai K Kovalszky I Gombas J Váradi B Machovich R 《Blood》2003,101(11):4380-4386
Myosin modulates the fibrinolytic process as a cofactor of the tissue plasminogen activator and as a substrate of plasmin. We report now that myosin is present in arterial thrombi and it forms reversible noncovalent complexes with fibrinogen and fibrin with equilibrium dissociation constants in the micromolar range (1.70 and 0.94 microM, respectively). Competition studies using a peptide inhibitor of fibrin polymerization (glycl-prolyl-arginyl-proline [GPRP]) indicate that myosin interacts with domains common in fibrinogen and fibrin and this interaction is independent of the GPRP-binding polymerization site in the fibrinogen molecule. An association rate constant of 1.81 x 10(2) M(-1) x s(-1) and a dissociation rate constant of 3.07 x 10(-4) s(-1) are determined for the fibrinogen-myosin interaction. Surface plasmon resonance studies indicate that fibrin serves as a matrix core for myosin aggregation. The fibrin clots equilibrated with myosin are stabilized against dissolution initiated by plasminogen and tissue-type plasminogen activator (tPA) or urokinase (at fibrin monomer-myosin molar ratio as high as 30) and by plasmin under static and flow conditions (at fibrin monomer-myosin molar ratio lower than 15). Myosin exerts similar effects on the tPA-induced dissolution of blood plasma clots. Covalent modification involving factor XIIIa does not contribute to this stabilizing effect; myosin is not covalently attached to the clot by the time of complete cross-linking of fibrin. Thus, our in vitro data suggest that myosin detected in arterial thrombi binds to the polymerized fibrin, in the bound form its tPA-cofactor properties are masked, and the myosin fibrin clot is relatively resistant to plasmin. 相似文献
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Szolnoki Z Somogyvári F Kondacs A Szabó M Bene J Havasi V Komlósi K Melegh B 《Thrombosis research》2003,109(5-6):265-269
Introduction: Platelet glycoprotein IIb/IIIa is a membrane receptor with a central function in the platelet adhesion and ultimately in the thrombus formation. Two major variants of the gene encoding the IIIa subunit, called PLA1 (A1) and PLA2 (A2), have been identified in the general population. There are indications that the A2 allele can also be associated with acute thrombosis or stroke. The purpose of this study was to study the distribution of the A2 allele in different vascular subtypes of stroke disease. Materials and methods: A total of 638 consecutive patients were analyzed and classified as having large vessel pathology (n=168) or a small vessel infarct (n=210). Localization of the vascular occlusions was deducted from analysis of the magnetic resonance imaging (MRI) scan results in stroke patients. The remainder patients were listed into a mixed vascular pathology group (n=167). Patients with other or poorly characterized stroke etiology were excluded from the study (n=93). Results: In the small vessel and mixed vascular pathology groups, the PLA2 allele frequency was similar to that in the controls. By contrast, PLA2 allele frequency was approximately two-fold higher in patients with large vessel pathology (23.3%) than in the stroke-free control subjects (11.7%, p<0.0005). Multivariate logistic regression analysis of data confirmed this association with an odds ratio (OR) of 2.9 (95% confidence interval [CI]: 1.6–4.9, p<0.0005). Conclusions: These data suggest that the PLA2 allele is more frequent in brain infarcts associated with large-vessel occlusion. 相似文献