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Xiaojin Liu Yan Wu Yanchun Zhou Liangming Zeng Tian Huang 《Biochemical and biophysical research communications》2009,386(1):181-185
Interleukin (IL)-33 is a recently described member of the IL-1 family and has been shown to induce production of T helper type 2 cytokines. In this study, an anti-IL-33 antibody was evaluated against pulmonary inflammation in mice sensitized and challenged with ovalbumin. The anti-IL-33 or a control antibody (150 μg/mouse) was given intraperitoneally as five doses before the sensitization and antigen challenge. Treatment with anti-IL-33 significantly reduced serum IgE secretion, the numbers of eosinophils and lymphocytes, and concentrations of IL-4, IL-5, and IL-13 in bronchoalveolar lavage fluid compared with administration of a control antibody. Histological examination of lung tissue demonstrated that anti-IL-33 significantly inhibited allergen-induced lung eosinophilic inflammation and mucus hypersecretion. Our data demonstrate for the first time that anti-IL-33 antibody can prevent the development of asthma in a mouse model and indicate that blockade of IL-33 may be a new therapeutic strategy for allergic asthma. 相似文献
23.
Low-cost, robust, and user-friendly diagnostic capabilities at the point-of-care (POC) are critical for treating infectious diseases and preventing their spread in developing countries. Recent advances in micro- and nanoscale technologies have enabled the merger of optical and fluidic technologies (optofluidics) paving the way for cost-effective lensless imaging and diagnosis for POC testing in resource-limited settings. Applications of the emerging lensless imaging technologies include detecting and counting cells of interest, which allows rapid and affordable diagnostic decisions. This review presents the advances in lensless imaging and diagnostic systems, and their potential clinical applications in developing countries. The emerging technologies are reviewed from a POC perspective considering cost effectiveness, portability, sensitivity, throughput and ease of use for resource-limited settings. 相似文献
24.
Autophagy is an intracellular degradation process for recycling macromolecules and organelles. It plays important roles in plant development and in response to nutritional demand, stress, and senescence. Organisms from yeast to plants contain many autophagy-associated genes (ATG). In this study, we found that a total of 33 ATG homologues exist in the rice [Oryza sativa L. (Os)] genome, which were classified into 13 ATG subfamilies. Six of them are alternatively spliced genes. Evolutional analysis showed that expansion of 10 OsATG homologues occurred via segmental duplication events and that the occurrence of these OsATG homologues within each subfamily was asynchronous. The Ka/Ks ratios suggested purifying selection for four duplicated OsATG homologues and positive selection for two. Calculating the dates of the duplication events indicated that all duplication events might have occurred after the origin of the grasses, from 21.43 to 66.77 million years ago. Semi-quantitative RT–PCR analysis and mining the digital expression database of rice showed that all 33 OsATG homologues could be detected in at least one cell type of the various tissues under normal or stress growth conditions, but their expression was tightly regulated. The 10 duplicated genes showed expression divergence. The expression of most OsATG homologues was regulated by at least one treatment, including hormones, abiotic and biotic stresses, and nutrient limitation. The identification of OsATG homologues showing constitutive expression or responses to environmental stimuli provides new insights for in-depth characterization of selected genes of importance in rice. 相似文献
25.
Hepatitis B virus(HBV) is a major cause of hepatocellular carcinoma(HCC). Its chronic infection can lead to chronic liver inflammation and the accumulation of genetic alterations to result in the oncogenic transformation of hepatocytes. HBV can also sensitize hepatocytes to oncogenic transformation by causing genetic and epigenetic changes of the host chromosomes. HBV DNA can insert into host chromosomes and recent large-scale whole-genome sequencing studies revealed recurrent HBV DNA integrations sites that may play important roles in the initiation of hepatocellular carcinogenesis. HBV can also cause epigenetic changes by altering the methylation status of cellular DNA, the post-translational modification of histones, and the expression of micro RNAs. These changes can also lead to the eventual hepatocellular transformation. These recent findings on the genetic and epigenetic alterations of the host chromosomes induced by HBV opened a new avenue for the development of novel diagnosis and treatments for HBV-induced HCC. 相似文献
26.
Xiaoyu Zhang Hailang Tong Zhiqiang Han Long Huang Jing Tian Zhixing Fu Yunyi Wu Ting Wang Deyi Yuan 《Physiology and Molecular Biology of Plants》2021,27(5):959
Camellia oleifera is believed to exhibit a complex intraspecific polyploidy phenomenon. Abnormal microsporogenesis can promote the formation of unreduced gametes in plants and lead to sexual polyploidy, so it is hypothesized that improper meiosis probably results in the formation of natural polyploidy in Camellia oleifera. In this study, based on the cytological observation of meiosis in pollen mother cells (PMCs), we found natural 2n pollen for the first time in Camellia oleifera, which may lead to the formation of natural polyploids by sexual polyploidization. Additionally, abnormal cytological behaviour during meiosis, including univalent chromosomes, extraequatorial chromosomes, early segregation, laggard chromosomes, chromosome stickiness, asynchronous meiosis and deviant cytokinesis (monad, dyads, triads), was observed, which could be the cause of 2n pollen formation. Moreover, we confirmed a relationship among the length–width ratio of flower buds, stylet length and microsporogenesis. This result suggested that we can immediately determine the microsporogenesis stages by phenotypic characteristics, which may be applicable to breeding advanced germplasm in Camellia oleifera.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-01002-5. 相似文献
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Fetuses of 12 near-term sheep were prepared for microsphere determination of cerebral blood flow. Experiments were performed 5 days postsurgery. The regional blood flows were measured in successive high (HV), low (LV) and high voltage electrocorticographic states. Comparisons were made between the observations made in the LV and averaged flanking HV cycles. Total cerebral blood flow was 95 +/- 8, 119 +/- 11 and 100 +/- 9 ml/min/100 g in HV, LV and HV, respectively. Low voltage electrocortical activity increased average cerebral blood flow by 22% (P less than 0.01). Significant changes were seen in all regions except the occipital cortex. The maximum change was observed in the thalamus in which the flows were 152 +/- 23, 243 +/- 35 and 138 +/- 20 ml/min/per 100 g tissue, respectively. The increase was 68% (P less than 0.001). The percent changes seen in the cerebrum are as follows: Frontal grey + 18%, frontal white + 22%, parietal white + 22%, temporal + 18%. A + 17% change was seen in the cord (P less than 0.03). It is concluded that in low voltage electrocortical activity all of the brain, except the occipital region, shows an increase in cerebral blood flow. This is probably secondary to a variance in cerebral activity. This preparation may be useful in localizing function in the fetal brain. 相似文献
29.
STAT6 ASODN对哮喘小鼠脾淋巴细胞影响的实验研究 总被引:1,自引:0,他引:1
目的研究STAT6反义寡核苷酸对哮喘小鼠脾淋巴细胞的影响作用。方法实验细胞分组:正常鼠空白组(A组)、正常鼠OVA组(B组)、哮喘空白组(C组)、哮喘OVA组(D组)、哮喘治疗组(E组)。正常设计并人工合成一段互补于小鼠STAT6 mRNA翻译起始区271-290的反义寡核苷酸片段,全链硫代修饰。用卵白蛋白和氢氧化铝复制哮喘模型,用淋巴细胞分离液分离脾淋巴细胞,进行体外培养并导入由阳离子脂质体转染剂Geneshuttle携带的反义寡核苷酸,观察反义寡核苷酸的转染对脾淋巴细胞STAT6蛋白表达水平及细胞培养上清中IL-4分泌水平的影响。免疫细胞化学观察脾淋巴细胞中STAT6蛋白的表达水平,同时采用酶联免疫吸附(ELISA)法测定脾细胞培养上清液中IL-4的浓度。结果D组细胞STAT6蛋白表达明显高于其余各组,均具有显著性差异(P均<0.01),STAT6 ASODN转染后,E组细胞该蛋白的表达量明显下降(P<0.01);D组脾淋巴细胞培养上清中IL-4分泌水平明显高于其余各组,均具有显著性差异(P均<0.01);STAT6 ASODN转染后,E组培养上清中IL-4分泌水平显著低于D组(P<0.01)。结论STAT6 ASODN可特异性抑制哮喘鼠脾淋巴细胞中STAT6蛋白的表达,并可特异性抑制脾淋巴细胞中IL-4的分泌,为反义基因技术治疗哮喘提供了依据。 相似文献
30.
Biomarkers of neurodegenerative disorders: How good are they? 总被引:11,自引:0,他引:11
Biomarkers are very important indicators of normal and abnormal biological processes. Specific changes in pathologies,biochemistries and genetics can give us comprehensive information regarding the nature of any particular disease. A good biomarker should be precise and reliable, distinguishable between normal and interested disease, and differentiable between different diseases. It is believed that biomarkers have great potential in predicting chances for diseases, aiding in early diagnosis, and setting standards for the development of new remedies to treat diseases. New technologies have enabled scientists to identify biomarkers of several different neurodegenerative diseases. The followings, for instance,are only a few of the many new biomarkers that have been recently identified: the phosphorylated tau protein and aggregated β-amyloid peptide for Alzheimer‘s disease (AD), α-synuclein contained Lewy bodies and altered dopamine transporter (DAT) imaging for Parkinson‘s disease (PD), SOD mutations for familial amyotrophic lateral sclerosis (ALS), and CAG repeats resulted from Huntington‘s gene mutations in Huntington‘s disease (HD). This article will focus on the most-recent findings of biomarkers belonging to the four mentioned neurodegenerative diseases. 相似文献