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81.
Zhen Wang Xiaoyan Du Daoyang Yu Yang Yang Gaoen Ma Xueli Jia Lulu Cheng 《European journal of histochemistry : EJH》2022,66(1)
Stroke is a brain system disease with a high fatality rate and disability rate. About 80% of strokes are ischemic strokes. Cerebral ischemia-reperfusion injury (CIRI) caused by ischemic stroke seriously affects the prognosis of stroke patients. The purpose of this study is to investigate the effect of sufentanil (SUF) on CIRI model rats. We used middle cerebral artery occlusion (MCAO) to make the CIRI model in rats and monitored region cerebral blood flow (rCBF) to ensure that blood flow was blocked and recanalized. We used ELISA and RT-PCR to detect the expression of inflammatory factors in rat serum and brain tissue. In addition, we detected the expression of metalloproteinase (MMP) 2, MMP9 and collagen IV in brain tissues and performed Evans blue (EB) assay to determine the permeability of the blood-brain barrier (BBB). Finally, we clarified the apoptosis of brain tissue through the TUNEL staining and the detection of caspase 3, Bcl2 and Bax. Various concentrations of SUF, especially 5, 10 and 25μg/kg of SUF, all alleviated the infarct size, neurological function and brain edema of MCAO rats. SUF pretreatment also effectively reduced the expression of inflammatory cytokines in MCAO rats, including interleukin (IL)-1β, IL-4, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF)-α. In addition, SUF also inhibited MMP2 and MMP9 and promoted the expression of collagen IV, indicating that SUF attenuated the destruction of the BBB. SUF also inhibited caspase 3 and Bax rats and promoted Bcl2 in MCAO rats, thus inhibiting cell apoptosis. SUF pretreatment effectively improved the neurological function and cerebral infarction of MCAO rats, inhibited excessive inflammation in rats, protected the BBB, and inhibited cell apoptosis in brain tissue.Key words: Sufentanil, cerebral ischemia-reperfusion injury, inflammation, blood-brain barrier 相似文献
82.
Ya-Ping Li Chen-Rui Liu Hui-Ling Deng Mu-Qi Wang Yan Tian Yuan Chen Yu-Feng Zhang Shuang-Suo Dang Song Zhai 《PLoS neglected tropical diseases》2022,16(1)
BackgroundThis research aimed to explore the association between the RIG-I-like receptor (RIG-I and MDA5 encoded by DDX58 and IFIH1, respectively) pathways and the risk or severity of hand, foot, and mouth disease caused by enterovirus 71 (EV71-HFMD). In this context, we explored the influence of gene methylation and polymorphism on EV71-HFMD.Methodology/Principal findings60 healthy controls and 120 EV71-HFMD patients, including 60 mild EV71-HFMD and 60 severe EV71-HFMD patients, were enrolled. First, MiSeq was performed to explore the methylation of CpG islands in the DDX58 and IFIH1 promoter regions. Then, DDX58 and IFIH1 expression were detected in PBMCs using RT-qPCR. Finally, imLDR was used to detect DDX58 and IFIH1 single-nucleotide polymorphism (SNP) genotypes. Severe EV71-HFMD patients exhibited higher DDX58 promoter methylation levels than healthy controls and mild EV71-HFMD patients. DDX58 promoter methylation was significantly associated with severe HFMD, sex, vomiting, high fever, neutrophil abundance, and lymphocyte abundance. DDX58 expression levels were significantly lower in mild patients than in healthy controls and lower in severe patients than in mild patients. Binary logistic regression analysis revealed statistically significant differences in the genotype frequencies of DDX58 rs3739674 between the mild and severe groups. GeneMANIA revealed that 19 proteins displayed correlations with DDX58, including DHX58, HERC5, MAVS, RAI14, WRNIP1 and ISG15, and 19 proteins displayed correlations with IFIH1, including TKFC, IDE, MAVS, DHX58, NLRC5, TSPAN6, USP3 and DDX58.Conclusions/SignificanceDDX58 expression and promoter methylation were associated with EV71 infection progression, especially in severe EV71-HFMD patients. The effect of DDX58 in EV71-HFMD is worth further attention. 相似文献
83.
Xiaoman Li Liang Wang Jialin Hao Qingfeng Zhu Min Guo Changjing Wu Sihui Li Qiqiang Guo Qiuhong Ren Ning Bai Fei Yi Bo Jiang Wenyu Zhang Yanling Feng Hongde Xu Han Jiang Xiaoyue Zhai Guohua Zhang Hong-long Ji Xuesong Yang Dan Zhang Jianhua Fu Jianjun Chang Xiaoyu Song Liu Cao 《International journal of biological sciences》2022,18(3):1107
The lamellar body (LB), a concentric structure loaded with surfactant proteins and phospholipids, is an organelle specific to type 2 alveolar epithelial cells (AT2). However, the origin of LBs has not been fully elucidated. We have previously reported that autophagy regulates Weibel-Palade bodies (WPBs) formation, and here we demonstrated that autophagy is involved in LB maturation, another lysosome-related organelle. We found that during development, LBs were transformed from autophagic vacuoles containing cytoplasmic contents such as glycogen. Fusion between LBs and autophagosomes was observed in wild-type neonate mice. Moreover, the markers of autophagic activity, microtubule-associated protein 1 light chain 3B (LC3B), largely co-localized on the limiting membrane of the LB. Both autophagy-related gene 7 (Atg7) global knockout and conditional Atg7 knockdown in AT2 cells in mice led to defects in LB maturation and surfactant protein B production. Additionally, changes in autophagic activity altered LB formation and surfactant protein B production. Taken together, these results suggest that autophagy plays a critical role in the regulation of LB formation during development and the maintenance of LB homeostasis during adulthood. 相似文献
84.
85.
Zhai Huqu Cao Shuqing Wan Jianmin Zhang Rongxian Lu Wei Li Liangbi Kuang Tingyun Min Shaokai Zhu Defeng Cheng Shihua 《中国科学:生命科学英文版》2002,45(6):637-646
The characteristics of dry matter production before and after heading and the relationships between photosynthesis of flag
leaves and dry matter accumulation in panicles were investigated on super high-yielding rice cv. Xieyou 9308 (the yield of
up to 12 t/ha) with rice cv. Xieyou 63 as a control. The results showed that (i) the capacity of dry matter production before
and after heading in Xieyou 9308, i.e. biomass and daily dry matter production, was remarkably higher than that in Xieyou
63, especially after heading; (ii) CO2 assimilation capacity in flag leaves in Xieyou 9308, namely Leaf Source Capacity (LSC), was also significantly higher than
that in Xieyou 63, and the supply of photosynthate in leaves and the demand of grain filling were completely synchronous in
Xieyou 9308, but photosynthetic function in flag leaves in Xieyou 63 declined sharply 20 days after heading and it was not
enough to meet the demand of grain filling. These results confirmed that high efficient photosynthetic function in leaves
after heading and its complete synchronization with grain filling are the key approaches to super high yield of rice. 相似文献
86.
寇氏隐甲藻(Crypthecodinium cohnii)细胞核骨架与中间纤维... 总被引:4,自引:2,他引:4
Nuclear matrix (NM) and intermediate filament (IF) scaffold in primitive eukaryote Crypthecodinium cohnii were shown using selective extraction together with embedment-free electron microscopy, whole mount cell preparation and immunoblot techniques. There exists a delicate NM-IF network spreading over cytoplasm and nucleus in dinoflagellate cells, however, nuclear lamina is undeveloped. The diameter of NM fiber is about 3-5 nm and IF is 10 nm. Chromosomes are connected with NM filament network. Immunoblot analysis showed that dinoflagellate contained keratin-like polypeptides (63 kD and 67 kD) while mammalian lamin antibodies did not crossreact with dinoflagellate total protein. Our experiment results demonstrated that a framework similar to NM-IF scaffold in mammalian cell appeared in primitive eukaryote. We propose that: (1) NM-IF scaffold is not restrict to vertebrate cell, and it may be originated from early stages of eukaryote evolution; (2) Keratin is probably very conservative; (3) Compared with IF, lamina might appear late in evolution, and some of primitive characteristics of dinoflagellate nucleus may be related to the lack of lamina. 相似文献
87.
X. B. Li C. Z. Liang H. G. Wu W. X. Zhai N. Huang L. H. Zhu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(6):702-708
A tandemly repeated DNA sequence (RRS7) was isolated from Oryza alta (CCDD). RRS7-related sequences were also found tandemly arrayed in genomes AA, BB, BBCC, CC, and EE, and a small amount of RRS7-related sequences were detected in genome FF and the Oryza species with unknown genomes. DNA sequence analysis of the 1844-bp insert of RRS7 revealed that it contained six tandemly repeated units, of which five were 155 bp in length and one was 194 bp in length and contained an imperfect internal 39-bp duplication. Southern blot analysis showed that the boundary sequence contained in RRS7 is a single-copy sequence. A 155-bp consensus sequence derived from the six monomeric repeats contained no internal repeat and showed no significant homology to other currently known sequences. The results of Southern blot and sequence analysis revealed that there are at least two subfamilies present in the RRS7 family; these are represented by the DraI site and the MspI site, respectively. Restriction digestion with two pairs of isoschizomers MboI/Sau3A and MspI/HpaII demonstrated that most of the C residues in the GATC sites and the internal C in the CCGG sites of the RRS7 family in O. Alta were methylated. The usefulness of the RRS7 family in determining the evolutionary relationship of the genome DD and other Oryza genomes is discussed. 相似文献
88.
89.
长白山劲松林场植物群落的分类和排序 总被引:5,自引:2,他引:5
将长白山白河林业局劲松林场的54块样地用聚类分析法划分成6个植被类群,再用PC-VTAB程序中经过改进的Braun-Blanquet学派的植被排表分析法进行综合,产生了鉴别概要表,为各个等级的植被类群筛选出诊断种。此外,还用鉴别种地样地记录进行主成分分析,以验证诊断种的有效性,结果表明,PC-VTAB中的植被排表分析法是筛选鉴别种的有效方法,而鉴别种以显著地提高植被分析和排序的质量。 相似文献
90.
Chong-Jun Yang Zhi-Xi Zhai Yu-Hai Guo Peng Gao 《植物学报(英文版)》2007,49(4):550-555
We investigated the role of the "sieve tube-companion cell complex" lining the tube periphery, particularly the microfilament and microtubule, in assisting the pushing of phloem sap flow. We made a simple phloem transport system with a living radish plant, in which the conducting channel was exposed for local treatment with chemicals that are effective in modulating protoplasmic movement (acetylcholine, (ACh) a neurotransmitter in animals and insects; cytochalasin B, (CB) a specific inhibitor of many cellular responses that are mediated by microfilament systems and amiprophos-methyl, (APM) a specific inhibitor of many cellular responses that are mediated by microtubule systems). Their effects on phloem transport were estimated by two experimental devices: (i) a comparison of changes in the amount of assimilates in terms of carbohydrates and ^14C-labeled photosynthetic production that is left in the leaf blade of treated plants; and (ii) distribution patterns of ^14C-labeled leaf assimilates in the phloem transport system. The results indicate that CB and APM markedly inhibited the transfer of photosynthetic product from leaf to root via the leaf vein, while ACh enhanced the transfer of photosynthetic product in low concentrations (5.0×10^-4 mol/L) but inhibited it in higher concentrations (2.0×10^-3 mol/L) from leaf to root via the leaf vein. Autoradiograph imaging clearly reveals that ACh treatment is more effective than the control, and both CB and APM treatments effectively inhibit the passage of radioactive assimilates. All of the results support the postulation that the peripheral protoplasm in the sieve tube serves not only as a passive semi-permeable membrane, but is also directly involved in phloem transport. 相似文献