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941.
942.
Physiological basis of different allelopathic reactions of cucumber and figleaf gourd plants to cinnamic acid 总被引:11,自引:0,他引:11
To provide an insight into the mechanism of interspecific interactions mediated by allelochemicals, cucumber and figleaf gourd seedlings were compared on their response to cinnamic acid, an autotoxin from root exudates of cucumber. Reactive oxygen species metabolism and plasma membrane H(+)-ATPase activity were examined in roots upon exposure to cinnamic acid. This exposure resulted in significant increases in activities of NADPH oxidase, superoxide dismutase, guaiacol peroxidase, and catalase, as well as in O(2)(.-) production and H(2)O(2) content, in cucumber roots but not in figleaf gourd roots. Notably, the cucumber roots produced significant amount of reactive oxygen species (ROS) immediately after cinnamic acid treatment, consequently increasing membrane peroxidation, decreasing membrane H(+)-ATPase activity, and losing root viability. By contrast, no such changes were observed in figleaf gourd roots. All these results indicated that there was an interspecies difference in the recognition of allelochemicals, which induced oxidative stress accompanied by root cell death in cucumber, an autotoxic plant, but not in figleaf gourd, a cucumber relative. 相似文献
943.
Circular RNA (circRNA) represents an important regulator in infantile pneumonia progression. To clarify the role of circ_0026579 in this disease, LPS was used to treat WI-38 cells to mimic inflammation injury. The levels of inflammatory factors were determined by ELISA assay. Cell proliferation and apoptosis were measured by MTT assay, EdU staining and flow cytometry. The protein levels of cyclinD1, cleaved-caspase-3 and insulin-like growth factor 2 (IGF2) were examined using Western blot analysis. Cell oxidative stress was assessed by detecting MDA level and SOD activity. The expression of circ_0026579, miR-24-3p and IGF2 were analyzed using quantitative real-time PCR, and the interaction between miR-24-3p and circ_0026579 or IGF2 was confirmed by dual-luciferase reporter assay and RIP assay. LPS induced inflammation in WI-38 cells. Circ_0026579 expression was promoted in LPS-induced WI-38 cells, and its knockdown alleviated LPS-induced WI-38 cells inflammation. MiR-24-3p was sponged by circ_0026579, and its expression was reduced by LPS. MiR-24-3p inhibitor reversed the regulation of circ_0026579 knockdown on LPS-induced WI-38 cells inflammation. IGF2 was targeted by miR-24-3p, and its expression could be enhanced by LPS. MiR-24-3p relieved the inflammation of WI-38 cells which could be abolished by IGF2 overexpression. Circ_0026579 positively regulated IGF2 expression through sponging miR-24-3p. Circ_0026579 knockdown alleviated LPS-induced WI-38 cells inflammation by miR-24-3p/IGF2 axis, suggesting that circ_0026579 might contribute to infantile pneumonia progression. 相似文献
944.
Yunzhong Zhang Ketao Jiang Guoqing Xie Jie Ding Su Peng Xiaoyu Liu Cheng Sun Xin Tang 《Journal of cellular physiology》2021,236(2):1345-1361
Fibroblast growth factor 21 (FGF21) as a metabolic stress hormone, is mainly secreted by the liver. In addition to its well‐defined roles in energy homeostasis, FGF21 has been shown to promote remyelination after injury in the central nervous system. In the current study, we sought to examine the potential roles of FGF21 in the peripheral nervous system (PNS) myelination. In the PNS myelin development, Fgf21 expression was reversely correlated with myelin gene expression. In cultured primary Schwann cells (SCs), the application of recombinant FGF21 greatly attenuates myelination‐associated gene expression, including Oct6, Krox20, Mbp, Mpz, and Pmp22. Accordingly, the injection of FGF21 into neonatal rats markedly mitigates the myelination in sciatic nerves. On the contrary, the infusion of the anti‐FGF21 antibody accelerates the myelination. Mechanistically, both extracellular signal‐regulated kinase (ERK) and p38 mitogen‐activated protein kinase (MAPK) were stimulated by FGF21 in SCs and sciatic nerves. Following experiments including pharmaceutical intervention and gene manipulation revealed that the p38 MAPK/c‐Jun axis, rather than ERK, is targeted by FGF21 for mediating its repression on myelination in SCs. Taken together, our data provide a new aspect of FGF21 by acting as a negative regulator for the myelin development process in the PNS via activation of p38 MAPK/c‐Jun. 相似文献
945.
Po-Chih Chang Ming-Li Hsieh Shih-Tsung Huang Hsin-Chieh Huang Yu-Chao Hsu Ching-Wei Huang Wei-Feng Ding Yu Chen 《Polish journal of microbiology》2022,71(3):301
This study aims to evaluate associations between the immunochromatographic rapid test technique and Trichomonas vaginalis (TV) infection in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in Taiwan. All patients received post-prostate massage urine (VB3) Trichomonas rapid tests. The demographic characteristics and urogenital symptoms of CP/CPPS were recorded. Routine urinalysis of VB3 was also performed, and laboratory examination results of semen were recorded if available. A total of 29 patients with TV infection and 109 without TV infection were enrolled, which reflected that the prevalence in patients with TV infection was approximately 21%. Patients with TV infection displayed a significantly higher frequency of suprapubic/lower abdominal pain (p = 0.034), semen leukocyte > 5/high-power field (HPF) (p = 0.020), and an inflammatory type (category IIIA) (p = 0.005) than patients without TV infection. A higher prevalence of TV infection was found in patients with category IIIA (47.37%). No significant difference was found in the symptom duration and other clinical symptoms. In conclusion, the high prevalence of TV infection was revealed in CP/CPPS patients using the VB3 rapid Trichomonas test, especially in CP/CPPS patients with category IIIA. Thus, rapid TV testing might be vital for CP/CPPS patients in the hospital. 相似文献
946.
红花胚珠和雌配子体发育 总被引:1,自引:2,他引:1
用石蜡切片法研究了红花的大孢子发生和雌配子体发育过程,得到以下结果:(1)胚珠发育为薄珠心类型,倒生胚珠,具单珠被。(2)胚囊发育蓼型。(3)有珠被绒毛层,珠被绒毡层起始于大孢子母细胞时期,单核胚囊阶段高度发育,受精后从合点端逐渐退化。珠孔塞细胞呈毛状。 相似文献
947.
Chen P Norris D Das J Spergel SH Wityak J Leith L Zhao R Chen BC Pitt S Pang S Shen DR Zhang R De Fex HF Doweyko AM McIntyre KW Shuster DJ Behnia K Schieven GL Barrish JC 《Bioorganic & medicinal chemistry letters》2004,14(24):6061-6066
A series of substituted 2-(aminoheteroaryl)-thiazole-5-carboxamide analogs have been synthesized as novel, potent inhibitors of the Src-family kinase p56Lck. Among them, compound 2 displayed superior in vitro potency and excellent in vivo efficacy. 相似文献
948.
Ting Hu Xiong Li Qinghua Zhang Kecheng Huang Yao Jia Ru Yang Fangxu Tang Qiang Tian Ding Ma Shuang Li 《PloS one》2015,10(4)
Background
The effect of neoadjuvant chemotherapy (NACT) on topographical distribution patterns of lymph node metastasis in cervical cancer was unknown.Methods
Patients with FIGO stage IB1-IIB who underwent radical surgery with or without NACT were enrolled (3527 patients). A matched-case comparison design was used to compare the effects of NACT on lymph node metastasis.Results
We analyzed groups of 167 and 140 patients who were diagnosed with lymph node metastasis in the matched primary surgery group and NACT group, respectively, and no significant difference was observed (p = 0.081). The incidence of lymph node metastasis was significantly decreased in the NACT-responsive group compared to the non-responsive group (18.4% vs. 38.6%, P<0.001). The metastatic rates for every lymph node group also declined in the NACT-responsive group except for the deep inguinal and the para-aortic lymph node groups. Clinical response, deep stromal, parametrial and lymph vascular invasions were independent risk factors for lymph node metastasis in the NACT group. Furthermore, deep stromal invasion and lymph vascular invasion, but not the response to NACT, were independently associated with upper LNM. The number of lymph nodes involved, response to NACT, tumor histology and a positive vaginal margin were independent prognostic factors affecting DFS or OS rates in node-positive patients treated with NACT plus radical surgery.Conclusion
The frequency and topographic distribution of LNM are not modified by NACT, and clinical non-responders showed more involved LNs. A systemic and extensive lymphadenectomy should be performed in patients treated with NACT plus surgery regardless of the response to NACT. 相似文献949.
Horizontal gene transfer (HGT), a process through which genomes acquire genetic materials from distantly related organisms, is believed to be one of the major forces in prokaryotic genome evolution.However, systematic investigation is still scarce to clarify two basic issues about HGT: (1) what types of genes are transferred; and (2) what influence HGT events over the organization and evolution of biological pathways. Genome-scale investigations of these two issues will advance the systematical understanding of HGT in the context of prokaryotic genome evolution. Having investigated 82 genomes, we constructed an HGT database across broad evolutionary timescales. We identified four function categories containing a high proportion of horizontally transferred genes: cell envelope, energy metabolism, regulatory functions, and transport/binding proteins. Such biased function distribution indicates that HGT is not completely random;instead, it is under high selective pressure, required by function restraints in organisms. Furthermore, we mapped the transferred genes onto the connectivity structure map of organism-specific pathways listed in Kyoto Encyclopedia of Genes and Genomes (KEGG). Our results suggest that recruitment of transferred genes into pathways is also selectively constrained because of the tuned interaction between original pathway members. Pathway organization structures still conserve well through evolution even with the recruitment of horizontally transferred genes. Interestingly, in pathways whose organization were significantly affected by HGT events, the operon-like arrangement of transferred genes was found to be prevalent. Such results suggest that operon plays an essential and directional role in the integration of alien genes into pathways. 相似文献
950.
Wu Lipeng Wang Yidong Zhang Shirong Wei Wenliang Kuzyakov Yakov Ding Xiaodong 《Plant and Soil》2021,463(1-2):523-535
Plant and Soil - Soil was sampled (0–20 cm) from a 5-year Yellow River Delta paddy field experiment: no fertilizers (Control), mineral fertilizers (NPK), and NPK plus organic... 相似文献