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41.
TGF-beta1 is a potent immunoregulatory cytokine. However, its impact on the generation and effector function of Ag-specific human effector memory CD8 T cells had not been evaluated. Using Ag-specific CD8 T cells derived from melanoma patients immunized with the gp100 melanoma Ag, we demonstrate that the addition of TGF-beta1 to the initial Ag activation cultures attenuated the gain of effector function by Ag-specific memory CD8 T cells while the phenotypic changes associated with activation and differentiation into effector memory were comparable to control cultures. These activated memory CD8 T cells consistently expressed lower mRNA levels for T-bet, suggesting a mechanism for TGF-beta1-mediated suppression of gain of effector function in memory T cells. Moreover, TGF-beta1 induced a modest expression of CCR7 on Ag-activated memory CD8 T cells. TGF-beta1 also suppressed cytokine secretion by Ag-specific effector memory CD8 T cells, as well as melanoma-reactive tumor-infiltrating lymphocytes and CD8 T cell clones. These results demonstrate that TGF-beta1 suppresses not only the acquisition but also expression of effector function on human memory CD8 T cells and tumor-infiltrating lymphocytes reactive against melanoma, suggesting that TGF-beta1-mediated suppression can hinder the therapeutic benefits of vaccination, as well as immunotherapy in cancer patients.  相似文献   
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A new series of 1,3-dipropyl-8-(1-phenylacetamide-1H-pyrazol-3-yl)-xanthine derivatives has been identified as potent A(2B) adenosine receptor antagonists. The products have been evaluated for their binding affinities for the human A(2B), A(1), A(2A), and A(3) adenosine receptors. N-(4-chloro-phenyl)-2-[3-(2,6-dioxo-1,3-dipropyl-2,3,6,7-tetrahydro-1H-purin-8-yl)-5-methyl-pyrazol-1-yl] (11c) showed a high affinity for the human A(2B) adenosine receptor K(i)=7nM and good selectivity (A(1), A(2A), A(3)/A(2B)>140). Synthesis and SAR of this novel class of compounds is presented herein.  相似文献   
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Oral poliovirus vaccine (OPV) is reported to be effective in treatment of recurrent herpes simplex (RHS). According to our observation during recent years, OPV was not only effective in management of RHS but also in some patients with concomitant recurrent aphthous stomatitis (RAS) reducing its severity and frequency. The purpose of this study was to evaluate the efficacy of OPV in the management of RAS. In a longitudinal, case--control study 48 patients with RAS were recruited. Twenty patients received OPV and 28 patients received placebo. OPV was administered in a dose of 4 drops at monthly intervals for 3 months to the study group while the control group received placebo. The results were registered in 3 months after the last dose. Eight cases (40%) in the OPV group showed significant reduction in the duration of the ulcers, while no change was seen in the control group (P = 0.048). The frequency of recurrence of RAS was reduced in 13 cases (65%) in the OPV group, and in 6 cases (21.4%) of the placebo group (P = 0.006). The severity of attacks was reduced in 12 cases (60%) in the OPV group and in 4 cases (14.3%) in the placebo group (P = 0.008). In conclusion OPV appeared to be effective in the management of RAS.  相似文献   
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The transport of auxin controls the rate, direction and localization of plant growth and development. The course of auxin transport is defined by the polar subcellular localization of the PIN proteins, a family of auxin efflux transporters. However, little is known about the composition and regulation of the PIN protein complex. Here, using blue‐native PAGE and quantitative mass spectrometry, we identify native PIN core transport units as homo‐ and heteromers assembled from PIN1, PIN2, PIN3, PIN4 and PIN7 subunits only. Furthermore, we show that endogenous flavonols stabilize PIN dimers to regulate auxin efflux in the same way as does the auxin transport inhibitor 1‐naphthylphthalamic acid (NPA). This inhibitory mechanism is counteracted both by the natural auxin indole‐3‐acetic acid and by phosphomimetic amino acids introduced into the PIN1 cytoplasmic domain. Our results lend mechanistic insights into an endogenous control mechanism which regulates PIN function and opens the way for a deeper understanding of the protein environment and regulation of the polar auxin transport complex.  相似文献   
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Background

Small for gestational age (SGA) has high frequency which increases the risk of long-term adverse outcomes. Thus the aim of this study was to evaluate peak systolic velocity Doppler of middle cerebral artery (MCA) in SGA fetus in order to find appropriate method to diagnosis SGA sooner.

Materials and Methods

This prospective longitudinal study was conducted on 90 pregnant women with a diagnosis of SGA fetus and 90 pregnant women with normal fetus. Then MCA and umbilical artery assessment were performed for all subjects and compared between two groups.

Results

Doppler assessment showed that umbilical artery PI was significantly higher in SGA group as compared to normal group (1.11±0.37 vs 0.98±0.18, P = 0.003), while MCA PI was significantly lower in SGA group (1.77±0.44 vs 1.92±0.47, P = 0.028). On the other hand, PSV did not differ between the groups (P = 0.592). Moreover, we found that PSV was more in SGA group by grouping maternal age (<27 years) (P = 0.006), and gestational age (>34 weeks) (P<0.001).

Conclusion

The results of this study suggest that MCA PI decreased significantly in SGA fetuses, while UA PI increased in this group. Moreover, PSV increased in this group when evaluated in different subgroups (based on maternal age and gestational age).
  相似文献   
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The study presents length‐weight relationships (LWRs) and length‐lenght relationships (LLRs) for two freshwater fish species from the Cheshmeh‐Langan River (Iran; 32°50′N, 50°04′E), a part of the Tigris drainage basin. Fish were sampled by electrofishing (Samus 725M) in August and September 2017. The LWRs and LLRs obtained showed a high level of correlation (r2 > .98).  相似文献   
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