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We report that stimulation of Mycobacterium tuberculosis secretory antigen- and tumor necrosis factor alpha-matured BALB/c mouse bone marrow dendritic cells (BMDCs) with anti-CD80 monoclonal antibody up-regulated CD86 levels on the cell surface. Coculture of these BMDCs with na?ve, allogeneic T cells now down-regulated T helper cell type 1 (Th1) responses and up-regulated suppressor responses. Similar results were obtained with splenic CD11c(+)/CD8a(-) DCs but not to the same extent with CD11c(+)/CD8a(+) DCs. Following coculture with T cells, only BMDCs and CD11c(+)/CD8a(-) DCs and not CD11c(+)/CD8a(+) DCs displayed increased levels of surface CD86, and further, coculturing these DCs with a fresh set of T cells attenuated Th1 responses and increased suppressor responses. Not only na?ve but even antigen-specific recall responses of the Th1-committed cells were modulated by DCs expressing up-regulated surface CD86. Further analyses showed that stimulation with anti-CD80 increased interleukin (IL)-10 and transforming growth factor-beta-1 levels with a concomitant reduction in IL-12p40 and interferon-gamma levels from BMDCs and CD11c(+)/CD8a(-) DCs and to a lesser extent, from CD11c(+)/CD8a(+) DCs. These results suggest that cross-talk between costimulatory molecules differentially regulates their relative surface densities leading to modulation of Th responses initiated from some DC subsets, and Th1-committed DCs such as CD11c(+)/CD8a(+) DCs may not allow for such modulation. Cognate antigen-presenting cell (APC):T cell interactions then impart a level of polarization on APCs mediated via cross-regulation of costimulatory molecules, which govern the nature of subsequent Th responses.  相似文献   
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Interleukin (IL)-1β is a key innate cytokine that is essential for immune activation and promoting the inflammatory process. However, abnormal elevation in IL-1β levels has been associated with unwanted clinical outcomes. IL-1β is the most extensively studied cytokine among the IL-1 family of cytokines and its role in pathology is well established. During the course of human immunodeficiency virus type 1 (HIV-1) infection, the level of this proinflammatory cytokine is increased in different anatomical compartments, particularly in lymphatic tissues, and this elevation is associated with disease progression. The aim of this review is to address the pathological roles play by IL-1β in the light of enhancing HIV-1 replication, driving immune cell depletion, and chronic immune activation. The role of IL-1β in HIV-1 transmission (sexually or vertically ‘from mother-to-child’) will also be discussed. Additionally, the impact of the available antiretroviral therapy regimens on the levels of IL-1β in HIV-1 treated patients is also discussed. Finally, we will provide a glance on how IL-1β could be targeted as a therapeutic strategy.  相似文献   
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Animal and human studies have shown that nerve stimulation enhances some effects of botulinum toxin (btx A) injection. Voluntary muscle activity might work similarly and would focus the effect of an injection into the active muscles. We studied the effects of exercise immediately after btx A injection in eight patients with writer's cramp with established response to btx A over two injection cycles with a single-blinded, randomized, crossover design. Immediately after the first study injection, they were randomly assigned to write continuously for 30 min or have their hand and forearm immobilized for 30 min. Following the second injection, they were assigned the alternate condition. Patients were assessed just before each injection, and at 2 weeks, 6 weeks, and 3 months post-injection. Assessment included objective strength testing, self-reported rating of benefit and weakness, and blinded evaluation of videotapes and writing samples of the patients writing a standard passage. Strength testing showed that the maximum weakness occurred at 2 weeks post-injection, but the benefit was maximum at 6 weeks post-injection. The "write" condition resulted in greater reduction in strength than the "rest" condition. Btx A treatment led to improvement in self-reported ratings, writer's cramp rating scale scores by blinded raters, and reduction in writing time, but the differences between the "write" and "rest" conditions were not significant. We conclude that voluntary muscle activity immediately after btx A injection leads to greater reduction in muscle strength. Our findings raise the possibility that voluntary muscle activation may allow reduction of btx A doses and favorably alter the balance of benefit and side effects of btx A injections.  相似文献   
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Using plant bio-components for Designing green metal nanoparticles was considered as one of the most important methods in nanomedical application field due to their eco-friendly, cheap source, easily obtainable and having a high detection result. In this report, we fabricated eco-friendly engineering and cost-effective technique for green selenium nanoparticles from 0.01 M H2SeO3 solution using Asteriscus graveolens leaves extract as reducing and a capping agent at ambient temperature. Spectral techniques have been used to identify the formatted Selenium nanoparticles such as UV–Vis, pH, XPs, FT-IR, XRD, LDS, Z.P, EDS, TEM and AFM spectroscopy, which showed a size of 20 nm with spherical shape. Herein, the multi-effect of decorated Se-NPs surface have been evaluated, firstly on the hemolysis that showed completely hemocompatibility. Cytotoxicity assay showed that Se-NPs have a high selective effect on the HepG2 apoptosis and which proved by phase-contrast microscopy. Furthermore, the effect of nanoparticles on the action of the mechanism internal revealed that Se-NPs significantly and rapidly increased the level of reactive oxygen species and lipid peroxidation, while caused decreased the potential of mitochondrial membrane and glutathione level, which they together responsible on regulating the HepG2 cells fate. Furthermore, Flow cytometry analysis gave high values about S and G2/M phases of cell cycle resulting from Se-NPs effectiveness. In the end, with all the recorded information that has been measured in this study, this report provides a suitable and effective pathway for the green fabrication of Se-NPs decorated by biomolecules having high anticancer inhibited.  相似文献   
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3′-Hydroxy-4′-methoxy-chroman-7-O-β-d-glucopyranoside 4 was first isolated from a natural source, together with three known compounds, the ferulic acid heptyl ester 1, naringenin 2, and 4,2′,4′-trihydroxy-6′-methoxychalcone-4′-O-β-d-glucopyranoside 3, which were isolated from peach [Prunus persica (L.) Batsch] fruits. These compounds were subjected to different virtual screening strategies in order to examine their activity to combat the COVID-19 outbreak. The study design composed of some major aspects: (a) docking with main protease (Mpro), (b) docking with spike protein, (c) 3D shape similarity study (Rapid Overlay Chemical Similarity-ROCS) to the clinically used drugs in COVID-19 patients, and finally, (d) the rule of five and the estimated pre-ADMT properties of the separated flavonoids. Docking study with Mpro of SARS-CoV-2 (PDB ID:6LU7, and 6Y2F) showed that compound 3, its aglycone part, and compound 4 have a strong binding mode to a protease receptor with key amino acids, especially Gln:166AA, and having a similar docking pose to co-crystalized ligands. Docking with the spike protein of SARS-CoV-2 illustrated that compounds 3 and 4 have a good binding affinity to PDB ID:6VSB through the formation of HBs with Asp:467A and Asn:422A. According to ROCS analysis, compounds 1, 3, and 4 displayed high similarities to drugs that prevent SARS-Co2 entry to the lung cells or block the inflammatory storm causing lung injury. Compounds 3 and 4 are good candidates for drug development especially because they showed predicted activity against SARS-CoV-2 through different mechanisms either by preventing genome replication or by blocking inflammatory storm that trigger lung injury. These compounds were isolated from peach fruit, and the study supports data and continues with the recommendation of peach fruits in controlling and managing COVID-19 cases.

3′-Hydroxy-4′-methoxy-chroman-7-O-β-d-glucopyranoside 4, together with three known compounds, ferulic acid heptyl ester 1, naringenin 2, and 4,2′,4′-trihydroxy-6′-methoxychalcone-4′-O-β-d-glucopyranoside 3, was isolated from peach fruits.  相似文献   
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