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An efficient transformation system was developed for multiple soybean [Glycine max (L.) Merrill.] cultivars using Agrobacterium-mediated gene transfer. A significantly high number of hygromycin-resistant somatic embryos (SEs) was obtained when immature zygotic cotyledons were inoculated with Agrobacterium tumefaciens strain KYRT1 and when the abaxial side of explants was oriented upwards (i.e., the adaxial side of explants was in contact with the medium). Most hygromycin-resistant SEs on selective medium were induced along the periphery of the abaxial side of cotyledonary explants. Extended periods of selection (up to 10 weeks post-cocultivation) increased the frequency of somatic embryogenesis, and more than 50% of selected SEs tested positive for beta-glucuronidase (GUS). Following maturation and regeneration of selected SEs, ten independent transgenic soybean plants of cv Jack were obtained, and the overall transformation frequency ranged from 1.1 to 1.7%. Six and two transgenic plantlets were obtained from cvs Dwight and Williams, respectively. In addition, transgenic suspension lines were established from cvs Jack, Williams, Dwight, Rend and Ina. Molecular analysis of embryogenic lines and/or transgenic plants, established from different cultivars, confirmed stable integration, expression, and/or inheritance of transgenes in both T0 and T1 plants.  相似文献   
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Respiratory syncytial virus (RSV) is one of the most important pathogens of infancy and early childhood. Here a fruit-based edible subunit vaccine against RSV was developed by expressing the RSV fusion (F) protein gene in transgenic tomato plants. The F-gene was expressed in ripening tomato fruit under the control of the fruit-specific E8 promoter. Oral immunization of mice with ripe transgenic tomato fruits led to the induction of both serum and mucosal RSV-F specific antibodies. The ratio of immunoglobulin subclasses produced in response to immunization suggested that a type 1 T-helper cell immune response was preferentially induced. Serum antibodies showed an increased titer when the immunized mice were exposed to inactivated RSV antigen.  相似文献   
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Background

Whether inhaled corticosteroids suppress airway inflammation in chronic obstructive pulmonary disease (COPD) remains controversial. We sought to determine the effects of inhaled corticosteroids on sputum indices of inflammation in stable COPD.

Methods

We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Databases for randomized, controlled clinical trials that used induced sputum to evaluate the effect of inhaled corticosteroids in stable COPD. For each chosen study, we calculated the mean differences in the concentrations of sputum cells before and after treatment in both intervention and control groups. These values were then converted into standardized mean differences to accommodate the differences in patient selection, clinical treatment, and biochemical procedures that were employed across original studies. If significant heterogeneity was present (p < 0.10), then a random effects model was used to pool the original data. In the absence of significant heterogeneity, a fixed effects model was used.

Results

We identified six original studies that met the inclusion criteria (N = 162 participants). In studies with higher cumulative dose (≥ 60 mg) or longer duration of therapy (≥ 6 weeks), inhaled corticosteroids were uniformly effective in reducing the total cell, neutrophil, and lymphocyte counts. In contrast, studies with lower cumulative dose (< 60 mg) or shorter duration of therapy (< 6 weeks) did not demonstrate a favorable effect of inhaled corticosteroids on these sputum indices.

Conclusions

Our study suggests that prolonged therapy with inhaled corticosteroids is effective in reducing airway inflammation in stable COPD.  相似文献   
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IntroductionMicrochimeric male fetal cells (MFCs) have been associated with systemic lupus erythematosus, and published studies have further correlated MFC with lupus nephritis (LN). In the present study, we evaluated the frequency of MFC in the renal tissue of patients with LN.MethodsTwenty-seven renal biopsies were evaluated: Fourteen were from women with clinical and laboratory findings of LN, and thirteen were from controls. Genomic DNA was extracted from kidney biopsies, and the male fetal DNA was quantified using real-time quantitative polymerase chain reactions for the detection of specific Y chromosome sequences.ResultsMFCs were detected in 9 (64%) of 14 of patients with LN, whereas no MFCs were found in the control group (P = 0.0006). No differences in pregnancy history were found between patients with LN and the control group. Significantly higher amounts of MFCs were found in patients with LN with serum creatinine ≤1.5 mg/dl. Furthermore, women with MFCs had significantly better renal function at the time of biopsy (P = 0.03). In contrast, patients with LN without MFCs presented with more severe forms of glomerulonephritis (World Health Organization class IV = 60% and class V = 40%).ConclusionsOur data indicate a high prevalence of MFCs in renal biopsy specimens from women with LN, suggesting a role for MFCs in the etiology of LN. The present report also provides some evidence that MFCs could have a beneficial effect in this disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0615-4) contains supplementary material, which is available to authorized users.  相似文献   
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The sugar alcohol mannitol is a carbohydrate with well-documented roles in both metabolism and osmoprotection in plants and fungi. In addition, however, mannitol is an antioxidant, and current research suggests that pathogenic fungi can secrete mannitol into the plant’s extracellular spaces during infection to suppress reactive oxygen-mediated host defenses. In response to pathogen attack, plants have been shown to secrete the normally symplastic enzyme, mannitol dehydrogenase (MTD). Given that MTD converts mannitol to the sugar mannose, extracellular MTD may be an important defense against mannitol-secreting fungal pathogens. Previous work demonstrated that overexpression of MTD in tobacco did, in fact, provide increased resistance to the mannitol-secreting fungal pathogen Alternaria alternata. In the present work we demonstrate that the fungal pathogen Botrytis cinerea also can secrete mannitol, and that overexpression of MTD in zonal geranium (Pelargonium × hortorum) in turn provides increased resistance to B. cinerea. These results are not only an important validation of previous work, but support the idea that MTD-overexpression might be used to engineer a broad variety of plants for resistance to mannitol-secreting fungal pathogens like B. cinerea for which specific resistance is lacking.  相似文献   
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We tested the hypothesis that excessive portal venous supply of long-chain fatty acids to the liver contributes to the development of insulin resistance via activation of the hypothalamus-pituitary-adrenal axis (HPA axis) and sympathetic system. Rats received an intraportal infusion of the long-chain fatty acid oleate (150 nmol/min, 24 h), the medium-chain fatty acid caprylate, or the solvent. Corticosterone (Cort) and norepinephrine (NE) were measured as indexes for HPA axis and sympathetic activity, respectively. Insulin sensitivity was assessed by means of an intravenous glucose tolerance test (IVGTT). Oleate infusion induced increases in plasma Cort (Delta = 13.5 +/- 3.6 microg/dl; P < 0.05) and NE (Delta = 235 +/- 76 ng/l; P < 0.05), whereas caprylate and solvent had no effect. The area under the insulin response curve to the IVGTT was larger in the oleate-treated group than in the caprylate and solvent groups (area = 220 +/- 35 vs. 112 +/- 13 and 106 +/- 8, respectively, P < 0.05). The area under the glucose response curves was comparable [area = 121 +/- 13 (oleate) vs. 135 +/- 20 (caprylate) and 96 +/- 11 (solvent)]. The results are consistent with the concept that increased portal free fatty acid is involved in the induction of visceral obesity-related insulin resistance via activation of the HPA axis and sympathetic system.  相似文献   
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BACKGROUND: Quantitative proteomics is an emerging field that encompasses multiplexed measurement of many known proteins in groups of experimental samples in order to identify differences between groups. Antibody arrays are a novel technology that is increasingly being used for quantitative proteomics studies due to highly multiplexed content, scalability, matrix flexibility and economy of sample consumption. Key applications of antibody arrays in quantitative proteomics studies are identification of novel diagnostic assays, biomarker discovery in trials of new drugs, and validation of qualitative proteomics discoveries. These applications require performance benchmarking, standardization and specification. RESULTS: Six dual-antibody, sandwich immunoassay arrays that measure 170 serum or plasma proteins were developed and experimental procedures refined in more than thirty quantitative proteomics studies. This report provides detailed information and specification for manufacture, qualification, assay automation, performance, assay validation and data processing for antibody arrays in large scale quantitative proteomics studies. CONCLUSION: The present report describes development of first generation standards for antibody arrays in quantitative proteomics. Specifically, it describes the requirements of a comprehensive validation program to identify and minimize antibody cross reaction under highly multiplexed conditions; provides the rationale for the application of standardized statistical approaches to manage the data output of highly replicated assays; defines design requirements for controls to normalize sample replicate measurements; emphasizes the importance of stringent quality control testing of reagents and antibody microarrays; recommends the use of real-time monitors to evaluate sensitivity, dynamic range and platform precision; and presents survey procedures to reveal the significance of biomarker findings.  相似文献   
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