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991.
Commercially available DOTAP is a racemic mixture of two enantiomers. The adjuvanticity of each isomer was examined using a peptide/lipid complex as a therapeutic vaccine in an established murine cervical cancer model. This simple vaccine consists of a cationic lipid (DOTAP) and a major histocompatibility complex (MHC) class I–restricted epitope of the Human Papillomavirus (HPV) 16 protein E7. Dose-dependent tumor regression experiments have been completed for racemic DOTAP/E7, (R)-DOTAP/E7 and (S)-DOTAP/E7. Tumor-bearing mice treated with (R)-DOTAP/E7 complexes have shown tumor regression in a dose-dependent manner comparable to those mice treated with a racemic DOTAP with E7 peptide. These data are supported by IFN-γ production by CD8+ splenocytes, in vivo cytotoxic T-lymphocytes (CTL) response, CD8+ tumor-infiltrating lymphocytes (TIL), and IFN-γ production by CD8+ TIL in (R)-DOTAP/E7-vaccinated mice. When (S)-DOTAP/E7 is delivered, tumor progression is delayed. While IFN-γ production is absent from CD8+ splenocytes in mice vaccinated with (S)-DOTAP/E7, IFN-γ production by CD8+ TIL is present, supporting our hypothesis that (S)-DOTAP has limited activity. Activation of bone marrow-derived dendritic cells by the enantiomeric formulations has also been evaluated, as well as cytokine production and toxicity with no considerable differences between the groups. The results show the DOTAP enantiomers act differently as adjuvants in vivo, with (R)-DOTAP being more effective at stimulating a CD8+ anti-tumor response.  相似文献   
992.
Recent studies have demonstrated that carotenoid-based traits are under the control of testosterone (T) by up-regulation of carotenoid carriers (lipoproteins) and/or tissue-specific uptake of carotenoids. T can be converted to dihydrotestosterone (DHT) and estradiol (E2), and variation in conversion rate may partly explain some contradictory findings in the literature. Moreover, most studies on the effect of T on sexual signals have focused on the male sex only, while in many species females show the same signal, albeit to a lesser extent. We studied the effects of T, DHT, and E2 treatment in male and female diamond doves Geopelia cuneata in which both sexes have an enlarged red eye ring, which is more pronounced in males. We first showed that this periorbital ring contains very high concentration of carotenoids, of which most are lutein esters. Both T and DHT were effective in enhancing hue, UV-chroma and size in both sexes, while E2 was ineffective. However, E2 dramatically increased the concentration of circulating lipoproteins. We conclude that in both sexes both color and size of the secondary sexual trait are androgen dependent. The action of androgens is independent of lipoproteins regulation. Potential mechanisms and their consequences for trade-off are discussed.  相似文献   
993.
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis (JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with 16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target for using probiotics in the management of IgE-mediated allergic disorders including JCPsis.  相似文献   
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Tomato leaf curl Taiwan virus (ToLCTWV) and Tomato spotted wilt virus (TSWV) are two major tomato viruses that cause serious economic losses. In this study, a partial C2 gene from ToLCTWV and the middle half of the N gene of TSWV were fused as a chimeric transgene to develop multiple virus resistance in transgenic plants. This construct was introduced into Nicotiana benthamiana and tomato by Agrobacterium-mediated transformation. Several transgenic lines showed no symptom post agro-inoculation with ToLCTWV and displayed high resistance to TSWV. The detection of siRNAs indicated that the resistance was via RNA silencing. This study demonstrated that linkage of gene segments from two viruses with distinct genomic organization, one DNA and the other RNA, can confer multiple virus resistance in transgenic plants via gene silencing.  相似文献   
998.
A strategy to obtain axenic cultures of the cyanobacterium Arthrospira sp. (‘platensis’) Lefevre 1963/M-132-1 strain, consisting of a series of physical and chemical procedures, and the application of an optimized pool of antibiotics, is described in this paper. This strategy, which is an inexpensive and fast way to obtain axenic cultures, can be applied to Arthrospira spp. from culture collections or samples from their natural habitats to eliminate a wide spectrum of contaminants. A high alkaline treatment (pH 12, using KOH) of 72 h is a determinant initial procedure applied to eliminate protozoa and Microcystis sp. Bacteria were eliminated by an optimal antibiotic pool treatment, and Chroococcus sp. residuals were discarded by serial dilution. Optimal concentrations of the antibiotics composing the pool were obtained by a 24 factorial central composite rotatable design (CCRD) and Response Surface Methodology (RSM), resulting in: ampicillin 61.6 μg/ml, penicillin 85.8 μg/ml, cefoxitin 76.9 μg/ml, and meropenem 38.9 μg/ml. The results also indicate that cefoxitin was the most effective antibiotic of this pool. After obtaining the axenic culture, identification of Lefevre 1963/M-132-1 strain was performed using amplification and sequencing of the ITS region (including part of 16S rRNA, tRNA Ile, ITS, tRNA Ala and part of 23S rRNA region) and fatty acid composition data. Data base comparison revealed that Lefevre strain is closely related to A. platensis species (99% identity), while fatty acid composition data suggested A. maxima. These seemingly contradictory results are discussed.  相似文献   
999.
In this research, ethanol production from carob pod extract (extract) using Zymomonas mobilis with medium optimized by Plackett–Burman (P–B) and response surface methodologies (RSM) was studied. Z. mobilis was recognized as useful for ethanol production from carob pod extract. The effects of initial concentrations of sugar, peptone, and yeast extract as well as agitation rate (rpm), pH, and culture time in nonhydrolyzed carob pod extract were investigated. Significantly affecting variables (P = 0.05) in the model obtained from RSM studies were: weights of bacterial inoculum, initial sugar, peptone, and yeast extract. Acid hydrolysis was useful to complete conversion of sugars to glucose and fructose. Nonhydrolyzed extract showed higher ethanol yield and residual sugar compared with hydrolyzed extract. Ethanol produced (g g−1 initial sugar, as the response) was not significantly different (P = 0.05) when Z. mobilis performance was compared in hydrolyzed and nonhydrolyzed extract. The maximum ethanol of 0.34 ± 0.02 g g−1 initial sugar was obtained at 30°C, initial pH 5.2, and 80 rpm, using concentrations (g per 50 mL culture media) of: inoculum bacterial dry weight, 0.017; initial sugar, 5.78; peptone, 0.43; yeast extract, 0.43; and culture time of 36 h.  相似文献   
1000.
A repetitive sequence of 491 bp, named pMD232-500, was isolated from S. cereale cv. Kustro using wheat SSR marker Xgwm232. GenBank BLAST search revealed that the sequence of pMD232-500 was highly similar to a part of retrotransposon Nusif-1. Fluorescence in situ hybridization (FISH) analysis using pMD232-500 as probe indicated that only 14 Thinopyrum intermedium chromosomes and all the chromosomes of S. cereale cv. Kustro bear FISH signals, however, no FISH signals were observed on Dasypyrum villosum chromosomes. In addition, the FISH signals were distributed on whole arms except their terminal regions. Further genomic in situ hybridization (GISH) analysis using genomic DNA from Pseudoroegneria spicata indicated that the 14 Th. intermedium chromosomes bearing FISH signals should belong to J genome. Thereafter, the repetitive elements pMD232-500 showed the unambiguous features of genomic constitution of Th. intermedium. In addition, the results in the present study have indicated the similarity of genomes from Th. intermedium and S. cereale.  相似文献   
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