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51.
Xiong XH Han S Wang JH Jiang ZH Chen W Jia N Wei HL Cheng H Yang YX Zhu B You S He JY Hou W Chen MX Yu CJ Jiao YH Zhang WC 《Journal of bacteriology》2011,193(1):315-316
Ketogulonicigenium vulgare is characterized by the efficient production of 2KGA from L-sorbose. Ketogulonicigenium vulgare Y25 is known as a 2-keto-L-gulonic acid-producing strain in the vitamin C industry. Here we report the finished, annotated genome sequence of Ketogulonicigenium vulgare Y25. 相似文献
52.
Li-bo Cheng Lei Cheng Hui-e Bi Zhi-qing Zhang Jin Yao Xiao-zhong Zhou Qin Jiang 《Biochemical and biophysical research communications》2014
Patients with age related macular degeneration (AMD) will develop vision loss in the center of the visual field. Reactive oxygen species (ROS)-mediated retinal pigment epithelium (RPE) cell apoptosis is an important contributor of AMD. In this study, we explored the pro-survival effect of α-melanocyte stimulating hormone (α-MSH) on oxidative stressed RPE cells. We found that α-MSH receptor melanocortin 1 receptor (MC1R) was functionally expressed in primary and transformed RPE cells. RPE cells were response to α-MSH stimulation. α-MSH activated Akt/mammalian target of rapamycin (mTOR) and Erk1/2 signalings in RPE cells, which were inhibited by MC1R siRNA knockdown. α-MSH protected RPE cells from hydrogen peroxide (H2O2)-induced apoptosis, an effect that was almost abolished when MC1R was depleted by siRNA. α-MSH-mediated S6K1 activation and pro-survival effect against H2O2 was inhibited by Akt inhibitors (perifosine, MK-2206 and LY294002). Further, mTOR inhibition by rapamycin, or by mTOR siRNA knockdown, diminished α-MSH’s pro-survival effect in RPE cells. Thus, Akt and its downstream mTOR signaling mediates α-MSH-induced survival in RPE cells. In summary, we have identified a new α-MSH–MC1R physiologic pathway that reduces H2O2-induced RPE cell damage, and might minimize the risk of developing AMD. 相似文献
53.
54.
Shengsong Xu Rui Guo Pei-Zhi Li Ke Li Yu Yan Jianlong Chen Guang Wang Beate Brand-Saberi Xuesong Yang Xin Cheng 《Journal of cellular physiology》2019,234(9):15167-15181
Dexamethasone (Dex), a synthetic glucocorticoid (GC) with long-lasting treatment effects, has been proved to exert a modulatory effect on osteoblast proliferation and differentiation during embryonic osteogenesis. However, it is still controversial if Dex exposure influences endochondral ossification and the underlying mechanism. In this study, chick embryos in vivo and preosteoblast cell cultures in vitro were utilized to investigate the effects of Dex on osteoblast formation and differentiation during the skeletal development. We first demonstrated that Dex exposure could shorten the long bones of 17-day chick embryos in vivo, and also downregulated the expressions of osteogenesis-related genes. Next, we established that Dex exposure inhibited the proliferation and viability of preosteoblasts-MC3TC-E1 cells, and the addition of insulin-like growth factor 1 (IGF-1) could dramatically rescue these negative effects. On the basis of remarkable changes in the rescue experiments, we next verified the important role of angiogenesis in osteogenesis by culturing isolated embryonic phalanges in Dulbecco's modified Eagle's medium culture or on the chick chorioallantoic membrane (CAM). Then, we transplanted MC3T3-E1 cell masses onto the CAM. The data showed that Dex exposure reduced the vessel density within the developed cell mass, concomitantly with the downregulation of IGF-1 pathway. We verified that the inhibition of blood vessel formation caused by Dex could be rescued by IGF-1 treatment using the CAM angiogenesis model. Eventually, we demonstrated that the shortened length of the phalanges in the presence of Dex could be reversed by IGF-1 addition. In summary, these findings suggested that the inhibition of Igf-1 signal caused by Dex exposure exerts a detrimental impact on the formation of osteoblasts and angiogenesis, which consequently shortens long bones during osteogenesis. 相似文献
55.
56.
The sericulture industry plays a very important role in our national economy. Silkworm (Bombyx mori) is always regarded as a model animal and biological reactor. There have been detailed studies on the structure, expression and control and molecular evolution of silk genes. However, few, if any, reports are available on the localization of structural genes in silkworm by molecular cytogenetics. The present experiment has tentatively localized theFib-H gene at the distal end of the 25th linkage group, namely at the 25-0.0 position, and verified thatFib-H has only one locus, thus providing a temporary solution to the problem about its localization. 相似文献
57.
转化生长因子-β对基质金属蛋白酶及其组织抑制因子调控的研究进展 总被引:5,自引:0,他引:5
基质金属蛋白酶 (MMPs) 及其组织抑制因子 (TIMPs) 参与调控胞外基质 (ECM) 的降解与重建,二者的协同作用以及表达的动态平衡保证组织的生理/病理形态结构建成,并完成生长、分化、维持、降解的往复周期. 转化生长因子-β(TGF-β)通过对MMPs和TIMPs家族成员因细胞类型而异的基因表达调控作用,表现出调节ECM重建的生物学效应. TGF-β可通过激活Smad通路、促分裂原活化蛋白激酶 (MAPK) 通路,以及刺激激活蛋白-1(AP-1)复合体的形成,完成对MMPs和TIMPs基因表达的调控功能. 相似文献
58.
<正>The heavily transmitted and mutated SARS-CoV-2 has constitutes a sustained threat to global health. A recent article published in Nature, firstly provided solid evidence confirming the cross-species transmission of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) from human to free-ranging white-tailed deer(Hale et al., 2022).More importantly, circulation of SARS-CoV-2 among deer rapidly resulted into new phylogenetic clades of deer-only viruses which were believed linkin... 相似文献
59.
CC Cheng N Lu CL Peng CC Chang FD Mai LY Chen MH Liao WM Wang J Chang 《Proteomics》2012,12(15-16):2584-2597
The survivals of gastric cancer (GC) patients are associated with early diagnosis and effective treatments. Therefore, it is urgent for the discovery of early GC biomarkers and tumor-targeting therapeutics. The aim of this study was to uncover putative tissue biomarkers of GC using 2D DIGE and then apply one of these specific markers in GC treatment. We found three putative biomarkers of GC with significant differences in expression level compared to adjacent normal tissue, including glucose-regulated protein 78 (GRP78) and glutathione s-transferase pi (GSTpi) with increased expression level, and alpha-1 antitrypsin (A1AT) with reduced expression level. The overexpressed GRP78 was used as a targeted protein for guiding the drugs to tumor cells, leading to more effective treatment for GC xenografts. Our results demonstrated that the designated GRP78-binding peptide based on the sequence, WIFPWIQL, was selectively prone to recognize and bind to GC MKN45 cells in vitro, and also improve the delivery efficiency of polymeric micelles-encapsulated drugs into tumor cells and displayed better therapeutic outcome in experimental animals. This strategy of GRP78-mediated drug targeting system may bring chemotherapeutic drugs with more precise targeting to tumor cells, leading to minimize side effects on patients after chemotherapy. 相似文献
60.
Calcium regulation of growth and differentiation of mouse epidermal cells in culture 总被引:137,自引:0,他引:137
Modification of the ionic calcium concentration in the culture medium markedly alters the pattern of proliferation and differentiation in cultured mouse epidermal cells. When medium calcium is lowered to 0.05--0.1 mM, keratinocytes proliferate rapidly with a high growth fraction and do not stratify, but continue to synthesize keratin. The cells grow as a monolayer for several months and can be subcultured and cloned in low Ca++ medium. Ultrastructural examination of cells cultured under low Ca++ conditions reveals widened intercellular spaces, abundant microvilli and perinuclear organization of tonofilaments and cellular organelles. Desmosomes are absent. Epidermal cells growing as a monolayer in low Ca++ can be induced to terminally differentiate by adding calcium to the level normally found in the culture medium (1.2 mM). Cell-to-cell contact occurs rapidly and desmosomes form within 2 hr. The cells stratify by 1--2 days and terminally differentiate with cell sloughing by 3--4 days. After Ca++ addition, DNA synthesis decreases with a lag of 5--10 hr and is totally inhibited within 34 hr. In contrast, RNA and protein synthesis continue at 40--50% of the low Ca++ level at day 3, a time when many cells are detaching from the culture dish. Keratin synthesis is unaffected by the Ca++ switch. 相似文献