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81.
Jang Hye Jin Choi Ji Yeon Kim Kangjoon Yong Seung Hyun Kim Yeon Wook Kim Song Yee Kim Eun Young Jung Ji Ye Kang Young Ae Park Moo Suk Kim Young Sam Cho Young-Jae Lee Sang Hoon 《Respiratory research》2021,22(1):1-9
IL-35 subunit EBI3 is up-regulated in pulmonary fibrosis tissues. In this study, we investigated the pathological role of EBI3 in pulmonary fibrosis and dissected the underlying molecular mechanism. Bleomycin-induced pulmonary fibrosis mouse model was established, and samples were performed gene expression analyses through RNAseq, qRT-PCR and Western blot. Wild type and EBI3 knockout mice were exposed to bleomycin to investigate the pathological role of IL-35, via lung function and gene expression analyses. Primary lung epithelial cells were used to dissect the regulatory mechanism of EBI3 on STAT1/STAT4 and STAT3. IL-35 was elevated in both human and mouse with pulmonary fibrosis. EBI3 knockdown aggravated the symptoms of pulmonary fibrosis in mice. EBI3 deficiency enhanced the expressions of fibrotic and extracellular matrix-associated genes. Mechanistically, IL-35 activated STAT1 and STAT4, which in turn suppressed DNA enrichment of STAT3 and inhibited the fibrosis process. IL-35 might be one of the potential therapeutic targets for bleomycin-induced pulmonary fibrosis. 相似文献
82.
Riptortus pedestris (Hemiptera: Alydidae) is a serious pest of soybean and sweet persimmon and uses male produced aggregation pheromone, (E)-2-hexenyl (Z)-3-hexenoate, (E)-2-hexenyl (E)-2-hexenoate, and tetradecyl isobutyrate to facilitate food location and recognition by conspecifics. Using electroantennogram (EAG) and greenhouse bioassay, we determined which antennal segment is involved in the detection of their aggregation pheromone. In the first EAG test using individual antennal segments, significant EAG responses to 1:1:1 mixture of the aggregation pheromone were observed only from the disti-flagellum segments of both male and female antennae at both pheromone doses tested (1 µg and 100 µg). In the following EAG tests using gradually removed antennal segment(s), EAG response was still maintained when the distal half of a disti-flagellum was surgically removed, while EAG response was lost when whole segment of disti-flagellum or other whole segments were gradually removed from intact antenna of both sexes. In greenhouse experiment, removing one or both segment(s) of disti-flagellum from male or female antennae resulted in significant reduction in their attraction to the aggregation pheromone. Together, these findings support that the disti-flagellum of R. pedestris houses olfactory neurons associated with attraction to their aggregation pheromone. 相似文献
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84.
BackgroundWe investigated the relationship between genetic alterations and 18F-FDG PET/CT findings in head and neck squamous cell carcinoma (HNSC).MethodsUsing mRNA-sequences of HNSC samples (480 patients) from the Cancer Genome Atlas (TCGA) portal, gene coexpression networks were constructed via a weighted correlation network analysis (WGCNA) algorithm, and their association with the tumor-to-blood signal ratio on 18F-FDG PET/CT data (21 patients) was explored. An elastic-net regression model was developed to estimate the PET tumor-to-blood ratio from the gene networks and to derive an FDG signature score (FDGSS). The FDGSS was evaluated with regard to clinical variables and general mutational profiles, as well as alterations to oncogenic signaling pathways.FindingsThe FDGSS values differed across clinical stages (p = 0.027), HPV-status (p< 0.001), and molecular subtypes of HNSC (p< 0.001). Multivariate Cox regression demonstrated that FDGSS was an independent predictor for overall (p = 0.019) and progression-free survival (p = 0.024). FDGSS positively correlated with total mutation rate (p = 0.016), aneuploidy (p < 0.001), and somatic copy number alteration scores (p < 0.001). CDKN2A in the cell cycle pathway (q = 0.014) and the TP53 gene in the TP53 pathway (q = 0.005) showed significant differences between high and low FDGSS patients.ConclusionFDGSS based on the gene coexpression network was associated with the mutational landscape of HNSC. 18F-FDG PET/CT is therefore a valuable tool for the in vivo imaging of these cancers, being able to visualize the glucose metabolism of the tumor and allow inferences to be made on the underlying genetic alterations in the tumor. 相似文献
85.
Interstitial cells of Cajal (ICCs) are the pacemakers of the gastrointestinal tract, and transient receptor potential melastatin type 7 (TRPM7) and Ca2+ activated Cl− channels (ANO1) are candidate the generators of pacemaker potentials in ICCs. The effects of D-erythro-sphingosine (SPH) and structural analogues of SPH, that is, N,N-dimethyl-Derythro-sphingosine (N,N-DMS), FTY720, and FTY720-P on the pacemaking activities of ICCs were examined using the whole cell patch clamp technique. SPH, N,N-DMS, and FTY720 decreased the amplitudes of pacemaker potentials in ICC clusters, but resting membrane potentials displayed little change. Also, perfusing SPH, N,N-DMS, or FTY720 in the bath reduced both inward and outward TRPM7-like currents in single ICCs, and inhibited ANO1 currents. The another structural analogue of SPH, FTY720-P was ineffective at the pacemaker potentials in ICC clusters and the TRPM7-like currents in single ICCs. Furthermore, FTY720- P had no effect on ANO1. These results suggest that SPH, N,N-DMS, and FTY720 modulate the pacemaker activities of ICCs, and that TRPM7 and ANO1 channels affect intestinal motility. 相似文献
86.
Seung Hyeok Seok Jong-Ik Heo Ji-Hye Hwang Yi-Rang Na Jang-Hyuk Yun Eun Hui Lee Jong-Wan Park Chung-Hyun Cho 《Molecules and cells》2013,35(6):550-556
The angiopoietin/Tie2 system is an important regulator of angiogenesis and inflammation. In addition to its functions in endothelial cells, Tie2 expression on non-endothelial cells allows for angiopoietin ligands to stimulate the cells. Although Ang1 is a strong Tie2 receptor agonist, little is known regarding the effect of Ang1 on non-endothelial cells, such as monocytes and macrophages. In this study, we found that Ang1 functionally binds to and stimulates monocytes via p38 and Erk1/2 phosphorylation. Ang1-mediated monocyte stimulation is associated with proinflammatory cytokine TNF-α expression. We also determined that Ang1 switched macrophage differentiation toward a pro-inflammatory phenotype, even in the presence of an anti-inflammatory mediator. These findings suggest that Ang1 plays a role in stimulating pro-inflammatory responses and could provide a new strategy by which to manage inflammatory responses. 相似文献
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88.
Na Na Kim Hyun Suk Shin Young Jae Choi Yuzo Yamamoto Kosuke Fukaya Hiroshi Ueda 《Marine and Freshwater Behaviour and Physiology》2013,45(6):397-410
Migrating fish such as salmonids are affected by external environmental factors and salinity changes are particularly important, influencing spawning migration. The aim of this study was to test whether changes in salinity would affect the expression of the hypothalamic-pituitary-gonadal (HPG) axis hormones (gonadotropin-releasing hormones (GnRHs) [salmon GnRH and chicken GnRH-II], GnRH receptors [GnRHR1 and GnRHR5], and mRNA of the gonadotropin hormone [GTH] subunits [GTHα, follicle stimulating hormone β, and luteinizing hormone β]) in chum salmon (Oncorhynchus keta). Fish were progressively transferred from seawater (SW) through 50% SW to freshwater (FW), and the relationship between the osmoregulatory hormone prolactin (PRL) and sexual maturation was determined. The expression and activity of HPG hormones and their receptors, and levels of estradiol-17β and PRL increased after fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis and PRL production in migrating chum salmon. These findings reveal details about the role of the endocrine system in maintaining homeostasis and stimulating sexual maturation and reproduction in response to salinity changes in this species. 相似文献
89.
Hyun Suk Shin Na Na Kim Gyung-Suk Kil 《Marine and Freshwater Behaviour and Physiology》2013,45(4):223-238
To establish the molecular basis of circadian rhythm control by melatonin receptors (MTs), we investigated the mitochondrial ribonucleic acid (mRNA) expressions of three types of MTs in different tissues of the olive flounder (Paralichthys olivaceus). All three types of MT mRNAs were expressed in the neural tissues, while MT1 mRNA was expressed in the peripheral tissues and MT2 and MT3 mRNAs were weakly expressed or undetected in these tissues. We observed increased MT mRNA expression in the neural tissues at night under both light–dark (LD) and constant dark (DD) conditions. Although the melatonin-treated cultured pineal gland samples showed similar diurnal variations with high-MT mRNA expression levels at night compared to those of untreated cultured pineal gland samples, the expression levels were considerably higher in the melatonin-treated samples. The plasma melatonin level also significantly increased at night. Under DD conditions, the expression patterns of MT mRNAs were similar to those under the LD photocycle, but the peak was lower and the circadian change patterns were less clear. These findings reinforce the hypothesis that MTs are active in processing light information, and that these genes are regulated by the circadian clock and light, thus suggesting that MTs play an important role in daily and circadian variations in the brain and retina of olive flounders. 相似文献
90.
Seung Ho Jung Arpit Saxena Kamaljeet Kaur Emma Fletcher Venkatesh Ponemone James M. Nottingham Joseph A. Sheppe Maria Petroni Jennifer Greene Kelly Graves Manjeshwar Shrinath Baliga Raja Fayad 《Cytokine》2013,61(2):459-468
Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the gastrointestinal tract that affect more than 3 million people worldwide, but the pathological etiology is still unknown. The overall purpose of our investigations was to elucidate the possibility of pathological causes of IBD, and therefore, we determined the difference of inflammatory cytokine profiles in adipose tissue macrophages (ATMs) and T lymphocytes (ATTs) obtained near active lesions of IBD; investigated whether the alteration in ATM activation induces genes involved in collagen formation; and evaluated the effects of fatty acid oxidation inhibitors on factors involved in inflammation and collagen production by ATMs in IBD. Adipose tissues (ATs) were collected near active lesions and also at the margin of resected segments of the bowel from IBD patients with ulcerative colitis (UC) and CD (n = 14/group). Normal appearing ATs from control subjects (n = 14) who had colon resection for adenocarcinoma were collected as far away from the cancer lesion as possible to rule out possible changes. Compared with inactive disease lesions, ATMs and ATTs from active lesions released more IL-6, IL-4 and IL-13. Treatments of cytokine IL-4 and/or IL-13 to ATMs reduced iNOS expression but increased Arg-I expression which were exacerbated when treated with T cell- and adipocyte-conditioned medium. However, fatty acid oxidation inhibitors prevented the effects of cytokines IL-4 and/or IL-13 on iNOS and Arg-I expressions. This study was the first to show the effect of IL-4 and IL-13 on collagen formation, through iNOS and Arg-I expressions, that was exacerbated in a condition that mimics in vivo condition of active lesions. Moreover, our study was the first to provide potential benefits of fatty acid oxidation inhibitors to ATMs on preventing collagen formation; thus, providing therapeutic implications for individuals with intestinal fibrosis and stricture lesions, although future study should be guaranteed to elucidate the underlying mechanisms. 相似文献