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Influenza is a major cause of morbidity and mortality in immunosuppressed persons, and vaccination often confers insufficient protection. IL-28B, a member of the interferon (IFN)-λ family, has variable expression due to single nucleotide polymorphisms (SNPs). While type-I IFNs are well known to modulate adaptive immunity, the impact of IL-28B on B- and T-cell vaccine responses is unclear. Here we demonstrate that the presence of the IL-28B TG/GG genotype (rs8099917, minor-allele) was associated with increased seroconversion following influenza vaccination (OR 1.99 p = 0.038). Also, influenza A (H1N1)-stimulated T- and B-cells from minor-allele carriers showed increased IL-4 production (4-fold) and HLA-DR expression, respectively. In vitro, recombinant IL-28B increased Th1-cytokines (e.g. IFN-γ), and suppressed Th2-cytokines (e.g. IL-4, IL-5, and IL-13), H1N1-stimulated B-cell proliferation (reduced 70%), and IgG-production (reduced>70%). Since IL-28B inhibited B-cell responses, we designed antagonistic peptides to block the IL-28 receptor α-subunit (IL28RA). In vitro, these peptides significantly suppressed binding of IFN-λs to IL28RA, increased H1N1-stimulated B-cell activation and IgG-production in samples from healthy volunteers (2-fold) and from transplant patients previously unresponsive to vaccination (1.4-fold). Together, these findings identify IL-28B as a key regulator of the Th1/Th2 balance during influenza vaccination. Blockade of IL28RA offers a novel strategy to augment vaccine responses.  相似文献   
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Six T-DNA/Ds launch pad lines (T0) previously generated by Agrobacterium-mediated transformation of M 35-1 genotype of sorghum were confirmed by PCR. T1 plants of all six lines showed 3:1 segregation when sprayed with 12 ppm Basta herbicide, indicating single copy insertion, which was also confirmed by left border flanking sequence tag. Calli derived from pNU435-T0(1) primary transformant was co-infected with Agrobacterium-carrying iAc construct for transient expression of transposase to generate stable Ds-tagged mutants in the T0 generation. All nine regenerants were PCR-positive for Ds. However, four contained intact T-DNA/Ds launch pad, while five plants carried empty launch pad, indicating transposition of the Ds. One of these plants, IDs-T0(8), was negative for iAc PCR, indicating that it was a stable Ds-tagged mutant. Of the four plants with intact T-DNA/Ds, IDs-T0(5) carrying iAc was a double transformant and mutagenic, which can generate mutants in the subsequent generation. Hence, the transient expression of transposase system in sorghum reported here can be employed for high throughput mutagenesis.  相似文献   
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The present study was designed to investigate the effect of temperature (20 °C, 24 °C, 28 °C and 32 °C) on the heamato-biochemical and histological alterations of Cyprinus carpio communis. Increase in the temperature showed significant decrease in the serum protein, while a reduced level of blood glucose at high temperature of 32 °C was observed leading to hypoglycemic conditions in the experimental fishes. A significant correlation (P<0.01) was observed between cholesterol (Cho) and triglycerides (TG) for different temperature treatments. Elevated blood urea nitrogen (BUN) at high temperatures was a good indicator of gill osmoregulatory failure. A variation of 86.40% and 38.33%, respectively, was noticed in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) at 32 °C over minimum experimental temperature of 20 °C. The increase in red blood cell (RBC) and Heamoglobin (Hb) concentration is associated with the decrease of mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC), could be the reason for observed poikilo-anisocytosis. Histological studies of different organs of experimental fishes showed accumulation of MMC's (melanomacrophagic centers) and atrophy of the interrenal tissue on exposure to various levels of temperature. These changes were related to severity of thermal stress, being most marked when high temperature was prolonged during acclimatization. Some fishes were found infested by protozoan parasite at elevated temperature of 32 °C. Increased levels of certain biochemical and haemotological parameters studied were strongly correlated with disease in the Cyprinus carpio communis species.  相似文献   
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Cholesterol is a fundamental molecule necessary for the maintenance of cell structure and is vital to various normal biological functions. It is a key factor in lifestyle-related diseases including obesity, diabetes, cardiovascular disease, and cancer. Owing to its altered serum chemistry status under pathological states, it is now being investigated to unravel the mechanism by which it triggers various health complications. Numerous clinical studies in cancer patients indicate an alteration in blood cholesterol level (either decreased or increased) in comparison to normal healthy individuals. This article elaborates on our understanding as to how cholesterol is being hijacked in the malignancy for the development, survival, stemness, progression, and metastasis of cancerous cells. Also, it provides a glimpse of how cholesterol derived entities, alters the signaling pathway towards their advantage. Moreover, deregulation of the cholesterol metabolism pathway has been often reported to hamper various treatment strategies in different cancer. In this context, attempts have been made to bring forth its relevance in being targeted, in pre-clinical and clinical studies for various treatment modalities. Thus, understanding the role of cholesterol and deciphering associated molecular mechanisms in cancer progression and therapy are of relevance towards improvement in the management of various cancers.  相似文献   
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