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61.
From the Cover: The chemodiversity of wines can reveal a metabologeography expression of cooperage oak wood 下载免费PDF全文
Régis D. Gougeon Marianna Lucio Moritz Frommberger Dominique Peyron David Chassagne Hervé Alexandre Fran?ois Feuillat Andrée Voilley Philippe Cayot Istvan Gebefügi Norbert Hertkorn Philippe Schmitt-Kopplin 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(23):9174-9179
Wine chemical compositions, which result from a complex interplay between environmental factors, genetic factors, and viticultural practices, have mostly been studied using targeted analyses of selected families of metabolites. Detailed studies have particularly concerned volatile and polyphenolic compounds because of their acknowledged roles in the organoleptic and therapeutic properties. However, we show that an unprecedented chemical diversity of wine composition can be unraveled through a nontargeted approach by ultrahigh-resolution mass spectrometry, which provides an instantaneous image of complex interacting processes, not easily or possibly resolvable into their unambiguous individual contributions. In particular, the statistical analysis of a series of barrel-aged wines revealed that 10-year-old wines still express a metabologeographic signature of the forest location where oaks of the barrel in which they were aged have grown. 相似文献
62.
Cytotoxicity is mandatory for CD8(+) T cell-mediated contact hypersensitivity 总被引:8,自引:0,他引:8 下载免费PDF全文
Kehren J Desvignes C Krasteva M Ducluzeau MT Assossou O Horand F Hahne M Kägi D Kaiserlian D Nicolas JF 《The Journal of experimental medicine》1999,189(5):779-786
Contact hypersensitivity (CHS) is a T cell-mediated skin inflammation induced by epicutaneous exposure to haptens in sensitized individuals. We have previously reported that CHS to dinitrofluorobenzene in mice is mediated by major histocompatibility complex (MHC) class I-restricted CD8(+) T cells. In this study, we show that CD8(+) T cells mediate the skin inflammation through their cytotoxic activity. The contribution of specific cytotoxic T lymphocytes (CTLs) to the CHS reaction was examined both in vivo and in vitro, using mice deficient in perforin and/or Fas/Fas ligand (FasL) pathways involved in cytotoxicity. Mice double deficient in perforin and FasL were able to develop hapten-specific CD8(+) T cells in the lymphoid organs but did not show CHS reaction. However, they did not generate hapten-specific CTLs, demonstrating that the CHS reaction is dependent on cytotoxic activity. In contrast, Fas-deficient lpr mice, FasL-deficient gld mice, and perforin-deficient mice developed a normal CHS reaction and were able to generate hapten-specific CTLs, suggesting that CHS requires either the Fas/FasL or the perforin pathway. This was confirmed by in vitro studies showing that the hapten-specific CTL activity was exclusively mediated by MHC class I-restricted CD8(+) T cells which could use either the perforin or the Fas/FasL pathway for their lytic activity. Thus, cytotoxic CD8(+) T cells, commonly implicated in the host defence against tumors and viral infections, could also mediate harmful delayed-type hypersensitivity reactions. 相似文献
63.
Homeostatic regulation of CD8+ T cells by perforin. 总被引:9,自引:0,他引:9
To prevent uncontrolled expansion, the massive proliferation of T cells during an acute immune response has to be followed by controlled deletion. Here we show that similar to Fas, perforin is not only an important effector molecule of cytotoxic T lymphocytes (CTL) but also involved in down-regulating peripheral T cells. Mice deficient for both the CTL effector molecule perforin and the apoptosis-inducing Fas ligand spontaneously develop infiltration of highly activated CD8(+) T cells in kidney and liver and die between 5 and 12 weeks of age. Injection of staphylococcal enterotoxin B (SEB) into perforin-deficient mice results in dramatically increased selective expansion and prolonged persistence of CD8(+), but not CD4(+), SEB-reactive T cells. Also, secondary immunization of TCR transgenic perforin-deficient mice with the lymphocytic choriomeningitis virus glycoprotein-derived epitope peptide leads to an increased proliferation of transgenic CD8(+) T cells, that is not explained by failure to deplete professional antigen-presenting cells. These results point to a novel mechanism of T cell homeostasis in which the acquisition of perforin-dependent cytotoxic activity regulates the expansion and persistence of CD8(+) effector T cells in vivo. 相似文献
64.
65.
G. Fü st E. Ujhelyi T. Hidv gi K. P l czi R. Mihalik S. Holl n K. Nagy M. Kirschfink 《Immunological investigations》1991,20(2):231-241
Different aspects of the relationship between the HIV infection and the complement system were studied. 1. No significant differences were found between seronegative controls, asymptomatic, and symptomatic (ARC, AIDS) HIV-seropositive patients in the plasma levels of complement components C4, Bf, and C3. 2. Using sensitive ELISA assays, a significant increase was observed in the levels of protein-protein complexes which are formed at the activation of the classical (C1r-C1s-C1-INH) and alternative (C3b-Bb-F) pathways, indicating that both complement pathways are activated in the HIV disease. No significant differences were found, however, in the levels of these complexes between the groups of asymptomatic and symptomatic HIV-infected patients. 3. Artificial immune complexes of synthetic peptides representing some immunodominant epitopes of HIV envelope (gp120, and gp41) proteins, and human polyclonal anti-HIV IgG were found to weakly activate both the classical and alternative complement pathways. 4. An elevated percentage of the lymphocytes carrying a complement activation fragment, C3d, was detected in the blood of HIV seropositive patients as compared to the seronegative controls. No significant positive correlation was found between the percentage of these cells and that of any T cell subsets tested. 相似文献
66.
67.
The supposed immunostimulatory actions of MSC, a new fermented wheat germ extract standardized to its benzoquinone composition (trade name: AVEMAR) were studied examining blastic transformation of peripheral blood lymphocytes of mice treated with MSC. It was found that MSC significantly increased the degree of blastic transformation caused by Concanavalin A. Using the B10LP to C57Bl skin graft system, MSC (0.03 and 3.0 g kg(-1) applied orally) acted in favour of restoring the immune function. On the other hand, 2,6-dimethoxy-p-benzoquinone (DMBQ), applied in equivalent doses (0.012 and 1.2 mg kg(-l)), did not shorten the rejection time of skin grafts. The immune restoring effect, as well as the blastic transformation enhancing potential of MSC may be exploited in various cases of decreased immune response. 相似文献
68.
Jacob Sands Martin C. Tammemägi Sebastien Couraud David R. Baldwin Andrea Borondy-Kitts David Yankelevitz Jennifer Lewis Fred Grannis Hans-Ulrich Kauczor Oyunbileg von Stackelberg Lecia Sequist Ugo Pastorino Brady McKee 《Journal of thoracic oncology》2021,16(1):37-53
Lung cancer is the leading cause of cancer-related deaths worldwide, accounting for almost a fifth of all cancer-related deaths. Annual computed tomographic lung cancer screening (CTLS) detects lung cancer at earlier stages and reduces lung cancer-related mortality among high-risk individuals. Many medical organizations, including the U.S. Preventive Services Task Force, recommend annual CTLS in high-risk populations. However, fewer than 5% of individuals worldwide at high risk for lung cancer have undergone screening. In large part, this is owing to delayed implementation of CTLS in many countries throughout the world. Factors contributing to low uptake in countries with longstanding CTLS endorsement, such as the United States, include lack of patient and clinician awareness of current recommendations in favor of CTLS and clinician concerns about CTLS-related radiation exposure, false-positive results, overdiagnosis, and cost. This review of the literature serves to address these concerns by evaluating the potential risks and benefits of CTLS. Review of key components of a lung screening program, along with an updated shared decision aid, provides guidance for program development and optimization. Review of studies evaluating the population considered “high-risk” is included as this may affect future guidelines within the United States and other countries considering lung screening implementation. 相似文献
69.
Changes in heart rate (HR) and finger mean blood pressure (MBP) during registration of the flow‐volume loop of forced respiration in healthy young subjects were studied. Breathing patterns of performing the flow‐volume loop of forced respiration (forced respiratory manoeuvre, FRM) as well as the related responses of cardiovascular parameters in different subjects were found to vary to a large extent. FRM has a remarkable influence on the cardiovascular system: during FRM the peak values of MBP were 19 ± 9 mmHg higher than baseline values and the peak values of HR were 30 ± 11 beats min–1 higher. We conclude that it is essential to pay attention to a remarkable elevation of blood pressure in functional breathing tests in patients with high blood pressure. 相似文献
70.
Eszter Rausz Agnes Szilgyi Boguslaw Nedoszytko Magdalena Lange Marek Niedoszytko Orsolya Lautner‐Csorba Andrs Falus Istvn Aladzsity Mrta Kokai Peter Valent Mrta Marschalko Bernadett Hidvgi Jzsef Szakonyi Judit Csomor Judit Vrkonyi 《British journal of haematology》2013,160(2):216-219
Mastocytosis is a rare disease with reported high interleukin‐6 (IL6) levels influencing disease severity. The present study investigated polymorphisms within the genes that encode IL6 and its receptor (IL6R) in relation to mastocytosis development in a case‐control design. Analysis of the IL6R Asp358Ala polymorphism showed that carriers of the AA genotype had a 2·5‐fold lower risk for mastocytosis than those with the AC or CC genotypes. No association with mastocytosis was found for the IL6−174G/C polymorphism, however, it may influence the effect of IL6R polymorphism. To the best of our knowledge this is the first study analysing IL6/IL6R polymorphisms in mastocytosis. 相似文献