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51.
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
52.
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55.
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
58.
The frequency of occurrence of amnesia, analgesia and time distortion during hypnotic dental treatments (n = 60) was investigated on high dental anxiety patients. Hypnosis with and without standardised direct suggestions related to amnesia, analgesia and time distortion were compared. Treatment of alert patients without direct suggestions (n = 10) were also used for comparison. Amnesia and time distortion was higher (p < or = 0.05) with the use of suggestions under hypnotic conditions, but analgesia was not significantly different. Alert appearance of the events were in all cases less (p < or = 0.01) than under hypnotic conditions. 相似文献
59.
We performed liver resection for focal liver disease in 266 patients between January 1, 1992 and December 31, 2001 at the University of Debrecen Medical and Health Science Center, Medical School of Medicine, 2nd Department of Surgery in Debrecen, Hungary. The indication was primary liver cancer in 35 cases, liver metastasis in 97 cases. The primary tumour and its liver metastases were removed synchronously in 28 patients (29.9%). Comparing the results of different operating methods we found the need of transfusion significantly less in "anterior" liver resections. Regarding operating time, complications and survival time there were no significant differences between the different operations. One patient died in the perioperative period because of cardiac failure and one because of DIC (1.5%). There were 4 complications which needed reoperation in the early postoperative period. Eighty of the patients were treated with systemic adjuvant chemotherapy (Mayo protocol), with added chemoembolisation in another 26 patients. This has not increased life expectancy significantly. Thirty-two patients are still alive, their average survival time is 21.2 (5 to 59) months. The average survival time of the 78 patients' who died is 16.5 (3 to 58) months. Twenty-two patients were lost out of our follow-up. 相似文献
60.
Simon E Péter M Benkó K Horkay E Erdélyi G Péter M Szúcs-Farkas Z Tóth J Kovács I Fülöp B 《Orvosi hetilap》2002,143(14):721-723
INTRODUCTION: The screening mammography decreases the mortality of female breast cancer. METHODS: A complex, independent centre of screening mammography has been operating in Debrecen since 1999. RESULTS: The number of the examinations were 10,399 in 1999 and 13,800 in 2000. The number of explored breast cancer cases were 43 (0.41%) in 1999 and 62 (0.45%) in 2000. CONCLUSION: Although the mortality reduction can be exactly measured after several years, we are convinced that the chances for a better life of these 107 women operated on with breast cancer in early state increased thanks to our project. The results of the breast cancer screening program in Debrecen fulfilled the professional requirements of mammographic service-screening. 相似文献