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101.
The microRNAs (miRNAs) are involved in multiple pathological processes among various types of tumors. However, the functions of miRNAs in benign brain tumors are largely unexplored. In order to explore the pathogenesis of the invasiveness in non-functional pituitary adenoma (NFPA), the miRNAs expression profile was analyzed between invasive and non-invasive non-functional pituitary adenoma by miRNAs microarray. Six most significant differentially expressed miRNAs were identified including four upregulated miRNAs hsa-miR-181b-5p, hsa-miR-181d, hsa-miR-191-3p, and hsa-miR-598 and two downregulated miRNAs hsa-miR-3676-5p and hsa-miR-383. The functions and corresponding signaling pathways of differentially expressed miRNAs were investigated by bioinformatics techniques, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The result of GO analysis indicates regulation of voltage-gated potassium channel activity, positive regulation of sodium ion transport, positive regulation of GTPase activity, negative regulation of Notch signaling pathway, etc. KEGG pathway reveals a series of biological processes, including prolactin signaling pathway, endocrine and other factor-regulated calcium reabsorption, fatty acid metabolism, neuroactive ligand-receptor interaction, etc. The miRNAs hsa-miR-181a-5p was verified by quantitative real-time PCR, and the expression level was in accordance with the microarray result. Our result can provide the evidence on featured miRNAs which play a prominent role in pituitary adenoma as effective biomarkers and therapeutic targets in the future.  相似文献   
102.
对TMV不同抗性番茄品种的叶绿体DNA限制性内切酶酶谱分析   总被引:1,自引:0,他引:1  
选用对TMV有抗性和敏感的番茄品种、制备其ct-DNA, 用限制性内切酶BumHI、EcoRI和PstI完全酶解, 三种酶切图谱与前人报道一致, 由酶切片段计算番茄ct-DNA。分子量约为156.9kb。比较抗性和敏感品种的ct-DNA图谱, 发现三种酶切图谱均存在差异, 但由差异片段计算分子量之和又很除近。我们推测这是由于检基顺序变异或小段DNA顺序插入或缺失所造成, 由此证明, 叶绿体基因组与核中的TMV抗性基因, 共同决定着植物体对TMV的抗性。  相似文献   
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IFN-alpha, a cytokine crucial for the innate immune response, also demonstrates antitumor activity. However, use of IFN-alpha as an anticancer drug is hampered by its short half-life and toxicity. One approach to improving IFN-alpha's therapeutic index is to increase its half-life and tumor localization by fusing it to a tumor-specific Ab. In the present study, we constructed a fusion protein consisting of anti-HER2/neu-IgG3 and IFN-alpha (anti-HER2/neu-IgG3-IFN-alpha) and investigated its effect on a murine B cell lymphoma, 38C13, expressing human HER2/neu. Anti-HER2/neu-IgG3-IFN-alpha exhibited potent inhibition of 38C13/HER2 tumor growth in vivo. Administration of three daily 1-microg doses of anti-HER2/neu-IgG3-IFN-alpha beginning 1 day after tumor challenge resulted in 88% of the mice remaining tumor free. Remarkably, anti-HER2/neu-IgG3-IFN-alpha demonstrated potent activity against established 38C13/HER2 tumors, with complete tumor remission observed in 38% of the mice treated with three daily doses of 5 microg of the fusion protein (p = 0.0001). Ab-mediated targeting of IFN-alpha induced growth arrest and apoptosis of lymphoma cells contributing to the antitumor effect. The fusion protein also had a longer in vivo half-life than rIFN-alpha. These results suggest that IFN-alpha Ab fusion proteins may be effective in the treatment of B cell lymphoma.  相似文献   
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Genetic differentiations and phylogeographical patterns of small organisms may be shaped by spatial isolation, environmental gradients, and gene flow. However, knowledge about genetic differentiation of rotifers at the intercontinental scale is still limited. Polyarthra dolichoptera and P. vulgaris are cosmopolitan rotifers that are tolerant to environmental changes, offering an excellent model to address the research gap. Here, we investigated the populations in Southeastern China and eastern North America and evaluated the phylogeographical patterns from their geographical range sizes, geographic–genetic distance relationships and their responses to spatial‐environmental factors. Using the mitochondrial cytochrome c oxidase subunit I gene as the DNA marker, we analyzed a total of 170 individuals. Our results showed that some putative cryptic species, also known as entities were widely distributed, but most of them were limited to single areas. The divergence of P. dolichoptera and P. vulgaris indicated that gene flow between continents was limited while that within each continent was stronger. Oceanographic barriers do affect the phylogeographic pattern of rotifers in continental waters and serve to maintain genetic diversity in nature. The genetic distance of P. dolichoptera and P. vulgaris populations showed significant positive correlation with geographic distance. This might be due to the combined effects of habitat heterogeneity, long‐distance colonization, and oceanographic barriers. Furthermore, at the intercontinental scale, spatial distance had a stronger influence than environmental variables on the genetic differentiations of both populations. Wind‐ and animal‐mediated transport and even historical events of continental plate tectonics are potential factors for phylogeography of cosmopolitan rotifers.  相似文献   
108.
Broadly neutralizing antibodies (bNAbs) are promising agents to prevent HIV infection and achieve HIV remission without antiretroviral therapy (ART). As with ART, bNAb combinations are likely needed to cover HIV’s extensive diversity. Not all bNAbs are identical in terms of their breadth, potency, and in vivo longevity (half-life). Given these differences, it is important to optimally select the composition, or dose ratio, of combination bNAb therapies for future clinical studies. We developed a model that synthesizes 1) pharmacokinetics, 2) potency against a wide HIV diversity, 3) interaction models for how drugs work together, and 4) correlates that translate in vitro potency to clinical protection. We found optimization requires drug-specific balances between potency, longevity, and interaction type. As an example, tradeoffs between longevity and potency are shown by comparing a combination therapy to a bi-specific antibody (a single protein merging both bNAbs) that takes the better potency but the worse longevity of the two components. Then, we illustrate a realistic dose ratio optimization of a triple combination of VRC07, 3BNC117, and 10–1074 bNAbs. We apply protection estimates derived from both a non-human primate (NHP) challenge study meta-analysis and the human antibody mediated prevention (AMP) trials. In both cases, we find a 2:1:1 dose emphasizing VRC07 is nearly optimal. Our approach can be immediately applied to optimize the next generation of combination antibody prevention and cure studies.  相似文献   
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There are multiple reports of autoimmune response in patients with lung cancer. To investigate whether a novel autoantibody is present in patients with lung cancer and evaluate its clinical diagnostic and prognostic value, sera from 10 patients with lung cancer and 10 normal individuals were analyzed using immunofluorescence and Western blotting. It was found that one serum sample from the patients with squamous carcinoma gave a fine speckled pattern staining in nucleus and had a high titer antinuclear autoantibody which could recognize 31 kD of nuclear protein isolated from both cancer cells and normal cells. The same patient’s serum was further used to immunoprecipitate the target antigen. The protein bands were excised from the SDS-PAGE gels and were analyzed with a Qstar Pulser I Quadrupole time-flight mass spectrometer, and the 31 kD target antigen was identified as U1-AsnRNP. To test the prevalence of anti-U1-AsnRNP antibody, sera from 93 patients including 36 squmaous carcinomas (SCC), 26 adenocarcinomas (Ad), and 31 small cell carcinomas (SCLC) were screened by Western blotting. The results demonstrated that anti-U1-A snRNP antibody was present in 50% of SCC sera, 26.9% of Ad sera and 54.8% of SCLC sera. In this paper, we report for the first time that anti-U1-AsnRNP antibody could be detected in the patients with lung cancer.  相似文献   
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