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201.
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   
202.
The mortality of patients with malignant gliomas remains high despite the advancement in multi-modal therapy including surgery, radio- and chemotherapy. Glioma stem cells (GSCs), sharing some characteristics with normal neural stem cells (NSCs), contribute to the cellular origin for primary gliomas and the recurrence of malignant gliomas after current conventional therapy. Accordingly, targeting GSCs proves to be a promising avenue of therapeutic intervention. The specific tropism of NSCs to GSCs provides a novel platform for targeted delivery of therapeutic agents. Tropism and mobilization of NSCs are enhanced by hypoxia through upregulating chemotactic cytokines and activating several signaling pathways. Moreover, hypoxia-inducible factors (HIFs) produced under hypoxic microenvironment of the stem cell niche play critical roles in the growth and stemness phenotypes regulation of both NSCs and GSCs. However, the definite cellular and molecular mechanisms of HIFs involvement in the process remain obscure. In this review, we focus on the pivotal roles of HIFs in migration of NSCs to GSCs and potential roles of HIFs in dictating the fates of migrated NSCs and targeted GSCs.  相似文献   
203.
204.
It has been verified that prochymosin is characterized by a two-stage refolding: dilution of unfolded protein into pH 11 buffer followed by neutralization at pH 8; the high-pH step is indispensable. Here we demonstrate that one-stage refolding around pH 8 can be achieved when GroE or 10-fold molar excess (rather than catalytic concentration) of protein disulfide isomerase (PDI) over prochymosin is present. The helping effect varies with the oxidation states of prochymosin. GroE and PDI increase the reactivation of the unfolded, partially reduced and the unfolded, oxidized prochymosin from 5% to 40% and from 50% to 100%, respectively. For the unfolded and fully reduced prochymosin, GroE does not have a positive effect, whereas PDI promotes renaturation from 2% to 28%. Based on our previous and present observations, we propose that at pH 8 there may be two kinds of incorrect interactions within and between prochymosin polypeptides leading to unproductive pathways: one prevents disulfide rearrangement, which can be avoided by high pH; the other interferes with acquisition of native conformation, which can be relieved by GroE and PDI.  相似文献   
205.
In this contribution, a simple, rapid, colorimeteric and selective assay for lysine was achieved by a controllable end-to-end assembly of gold nanorods (AuNRs) in the presence of Eu(3+) and lysine. This one-pot end-to-end assembly of 11-mercaptoundecanoic acid (MUA) modified AuNRs was occurred in Britton-Robinson buffer of pH 6.0, which involves the coordination binding between Eu(3+) and COO(-) groups as well as the electrostatic interaction of the COO(-) groups of MUA with the -NH(3)(+) group of lysine. As monitored by absorption spectra, scanning electron microscopic (SEM) images and dynamic light scattering (DLS) measurement, the end-to-end chain assembly results in large red-shift in the longitudinal plasmon resonance absorption (LPRA), giving red-to-blue color change of AuNRs. Importantly, it was found that the red-shift of LPRA is linearly proportional to the concentrations of lysine in the range of 5.0×10(-6)-1.0×10(-3)M with the limit of detection (LOD) being 1.6×10(-6)M (3σ/k). This red-shift of LPRA is highly selective, making it possible to develop a rapid, selective and visual assay for lysine in food samples.  相似文献   
206.
Aseptic loosening is the most common long-term complication of total joint replacement, which is associated with the generation of wear debris. The purpose of this study was to investigate the inhibitory effect of small interfering RNA (siRNA) targeting tumor necrosis factor-α (TNF-α) on wear debris-induced inflammation. A local delivery of lentivirus-mediated TNF-α siRNA into the modified murine air pouch, which was stimulated by polymethylmethacrylate (PMMA) particles, resulted in significant blockage of TNF-α both in mRNA and protein levels for up to 4 weeks. In addition, significant down-regulation of interleukin-1 (IL-1) and interleukin-6 (IL-6) was observed in TNF-α siRNA-treated pouches. The safety profile of gene therapy was proven by Bioluminescent assay and quantitative fluorescent flux. Histological analysis revealed less inflammatory responses (thinner pouch membrane and decreased cellular infiltration) in TNF-α siRNA-treated pouches. These findings suggest that local delivery of TNF-α siRNA might be an excellent therapeutic candidate to inhibit particle-induced inflammation.  相似文献   
207.
Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction to ice adhesion strength.We tried to partially-embed siliea nanopnarticles into microscale fabrics of a commercial polyamide mesh.Then,the area fraction could be determined by altering the mesh size.Generally,the ice adhesion strength decreases as the area fraction decreases.An ice adhesion strength of~1.9 kPa and a delayed freezing time of~1048 s can be obtained.We attribute the low ice adhesion strength to the combination of superhydro-phobicity and stress concentration.The superhydrophobicity prohibits the water from penetrating into the voids of the meshes,and the small actual contact area leads to stress concentration which promotes interfacial crack propagation.Moreover,our superhydrophobic mesh simultaneously exhibis a micro-nano hierarchical structure and a partally-cmbedded structure.Therefore,the as-prepared superhydrophobic mesh retained the ieephobicity after 20 icingldeicing cycles,and maintained its superhydrophobicity even afier 60 sandpaper-abrasion cycles and a 220"C thermal treatment.  相似文献   
208.
Liu  Zhenyang  Wang  Junyu  Tong  Haibo  Wang  Xiangyang  Zhang  Dong  Fan  Qin 《Neurochemical research》2020,45(7):1614-1625
Neurochemical Research - Glioma is a common invasive cancer with unfavorable prognosis in patients. Long non-coding RNAs (lncRNAs) exert significant functions in carcinogenesis of various cancers...  相似文献   
209.

Background

Tetherin is a recently identified antiviral restriction factor that restricts HIV-1 particle release in the absence of the HIV-1 viral protein U (Vpu). It is reminiscent of APOBEC3G and TRIM5a that also antagonize HIV. APOBEC3G and TRIM5a have been demonstrated to evolve under pervasive positive selection throughout primate evolution, supporting the red-queen hypothesis. Therefore, one naturally presumes that Tetherin also evolves under pervasive positive selection throughout primate evolution and supports the red-queen hypothesis. Here, we performed a detailed evolutionary analysis to address this presumption.

Methodology/Principal Findings

Results of non-synonymous and synonymous substitution rates reveal that Tetherin as a whole experiences neutral evolution rather than pervasive positive selection throughout primate evolution, as well as in non-primate mammal evolution. Sliding-window analyses show that the regions of the primate Tetherin that interact with viral proteins are under positive selection or relaxed purifying selection. In particular, the sites identified under positive selection generally focus on these regions, indicating that the main selective pressure acting on the primate Tetherin comes from virus infection. The branch-site model detected positive selection acting on the ancestral branch of the New World Monkey lineage, suggesting an episodic adaptive evolution. The positive selection was also found in duplicated Tetherins in ruminants. Moreover, there is no bias in the alterations of amino acids in the evolution of the primate Tetherin, implying that the primate Tetherin may retain broad spectrum of antiviral activity by maintaining structure stability.

Conclusions/Significance

These results conclude that the molecular evolution of Tetherin may be attributed to the host–virus arms race, supporting the Red Queen hypothesis, and Tetherin may be in an intermediate stage in transition from neutral to pervasive adaptive evolution.  相似文献   
210.
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