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161.
Mast cells (MC) are a key effector cell in multiple types of immune responses, including atopic conditions. Allergic diseases have been steadily rising across the globe, creating a growing public health problem. IgE-mediated activation of MCs leads to the release of potent mediators that can have dire clinical consequences. Current therapeutic options to inhibit MC activation and degranulation are limited; thus, a better understanding of the mechanisms that regulate MC effector functions in allergic inflammation are necessary in order to develop effective treatment options with minimal side effects. Several cytokines have been identified that play multifaceted roles in regulating MC activation, including TGFβ, IL-10, and IL-33, and others that appear to serve primarily anti-inflammatory functions, including IL-35 and IL-37. Here, we review the literature examining cytokines that regulate MC-mediated allergic immune responses.  相似文献   
162.
Apoptosis plays a key role in the effective removal of excessive and defective germ cells, which is essential for sequential hermaphroditism and sex change in vertebrates. The ricefield eel, Monopterus albus is a protogynous hermaphroditic fish that undergoes a sequential sex change from female to male. Previous studies have demonstrated that apoptosis is involved in sex change in M. albus. However, the apoptotic signaling pathway is unclear. In the current study, we explored the underlying mechanism of apoptosis during gonadal development and focused on the role of the mitochondrial apoptosis signaling pathway in sex change in M. albus. Flow cytometry was performed to detect apoptosis in gonads at five sexual stages and ovary tissues exposed to hydrogen peroxide (H2O2) in vitro. Then the expression patterns of key genes and proteins in the mitochondrial pathway, death receptor pathway and endoplasmic reticulum (ER) pathway were examined. The results showed that the apoptosis rate was significantly increased in the early intersexual stage and then decreased with the natural sex change from female to male. Quantitative real-time PCR revealed that bax, tnfr1, and calpain were mainly expressed in the five stages. ELISA demonstrated that the relative content of cytochrome-c (cyt-c) in the mitochondrial pathway was significantly higher than that of caspase8 and caspase12, with a peak in the early intersexual stage, while the levels of caspase8 and caspase12 peaked in the late intersexual stage. Interestingly, the Pearson’s coefficient between cyt-c and the apoptosis rate was 0.705, which suggests that these factors are closely related during the gonadal development of M. albus. Furthermore, the cyt-c signal was found to be increased in the intersexual stage by immunohistochemistry. After incubation with H2O2, the mRNA expression of mitochondrial pathway molecules such as bax, apaf-1, and caspase3 increased in ovary tissues. In conclusion, the present results suggest that the mitochondrial apoptotic pathway may play a more important role than the other apoptotic pathways in sex change in M. albus.  相似文献   
163.
The selective antiproliferation to oral cancer cells of Physalis peruviana-derived physapruin A (PHA) is rarely reported. Either drug-induced apoptosis and DNA damage or DNA repair suppression may effectively inhibit cancer cell proliferation. This study examined the selective antiproliferation ability of PHA and explored detailed mechanisms of apoptosis, DNA damage, and repair. During an ATP assay, PHA provided high cytotoxicity to two oral cancer cell lines (CAL 27 and Ca9-22) but no cytotoxicity to two non-malignant oral cells (HGF-1 and SG). This selective antiproliferation of PHA was associated with the selective generation of reactive oxygen species (ROS) in oral cancer cells rather than in non-malignant oral cells, as detected by flow cytometry. Moreover, PHA induced other oxidative stresses in oral cancer cells, such as mitochondrial superoxide generation and mitochondrial membrane potential depletion. PHA also demonstrated selective apoptosis in oral cancer cells rather than non-malignant cells in annexin V/7-aminoactinmycin D and caspase 3/7 activity assays. In flow cytometry and immunofluorescence assays, PHA induced γH2AX expressions and increased the γH2AX foci number of DNA damages in oral cancer cells. In contrast, the mRNA expressions for DNA repair signaling, including homologous recombination (HR) and non-homologous end joining (NHEJ)-associated genes, were inhibited by PHA in oral cancer cells. Moreover, the PHA-induced changes were alleviated by the oxidative stress inhibitor N-acetylcysteine. Therefore, PHA generates selective antiproliferation, oxidative stress, and apoptosis associated with DNA damage induction and DNA repair suppression in oral cancer cells.  相似文献   
164.
Reversible protein phosphorylation mediated by protein kinases and phosphatases plays important roles in the regulation of leaf senescence. We previously reported that the senescence-associated leucine-rich repeat receptor-like kinase AtSARK autophosphorylates on both serine/threonine and tyrosine residues and functions as a positive regulator of Arabidopsis leaf senescence; the senescence-suppressed protein phosphatase SSPP interacts with and dephosphorylates the cytoplasmic domain of AtSARK, thereby negatively regulating leaf senescence. Here, 27 autophosphorylation residues of AtSARK were revealed by mass spectrometry analysis, and six of them, including two Ser, two Thr, and two Tyr residues, were further found to be important for the biological functions of AtSARK. All site-directed mutations of these six residues that resulted in decreased autophosphorylation level of AtSARK could significantly inhibit AtSARK-induced leaf senescence. In addition, mutations mimicking the dephosphorylation form of Ser384 (S384A) or the phosphorylation form of Tyr413 (Y413E) substantially reduced the interaction between AtSARK and SSPP. All results suggest that autophosphorylation of AtSARK is essential for its functions in promoting leaf senescence. The possible roles of S384 and Y413 residues in fine-tuning the interaction between AtSARK and SSPP are discussed herein.  相似文献   
165.
唐芹  马力 《科普研究》2008,3(2):47-51
采用查阅资料、现场观察、定量及定性调查等研究方法,以辽宁省农村居民、沈阳市社区居民及北京市农民建筑工为目标人群,了解到农村居民、城市居民、农民建筑工的卫生科普需求以及卫生科普传播方式的评价与选择存在差异,提出调整卫生科普内容、改进卫生科普传播方式及管理工作的建议.  相似文献   
166.
砂岩凝析气藏见水后开发效果迅速变差,见水后治理成本高、难度大.塔河油田AT1区块T2a3凝析气藏存在井网分布不均导致局部采速过高、储层非均质性严重、开发初期采气强度偏大、前期认识存在局限性等问题,通过捕捉生产动态中的异常信号,认为气藏存在底油,并据此形成了以油基堵剂堵水等为代表的改善开发效果的针对性技术手段.通过利用隔夹层和平面非均质性进行剩余油气挖潜,取得了较好的治理效果.  相似文献   
167.
塔河油田碳酸盐岩油藏具有埋藏深、非均质性强的特点,主要储集空间以溶孔、溶洞和裂缝为主,裂缝为主要渗流通道。随着油田能量的递减,注水做为补充能量最经济有效的方式得到大力推广。根据物质平衡原理,依托酸压曲线、注水指示曲线、能量指示曲线,对注水进行定量化计算,精细注水,明确注采关系,优化注采参数,推动油田提高水驱效率和采收率。  相似文献   
168.
Perovskite solar cells (PSCs) emerging as a promising photovoltaic technology with high efficiency and low manufacturing cost have attracted the attention from ...  相似文献   
169.
The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interfer?ence (EMI) shielding materials to ...  相似文献   
170.
As promising anodes for sodium-ion batteries, metal sulfides ubiquitously suffer from low-rate and high-plateau issues, greatly hindering their application in f...  相似文献   
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