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821.
Piezoelectric Pump Used in Bionic Underwater Propulsion Unit 总被引:1,自引:0,他引:1
A new piezoelectric pump can pump liquid either forward or backward and adjust the flow rate. Thus an object can be driven forward or backward at different speeds. The driver of the pump, a circular piezoelectric plate, is modelled by Finite Element Method (FEM) in ANSYS and its performance is simulated and analyzed. The pump gives the best performance when the driving signals of the inlet and outlet valves have a bigger duty cycle and the plate has a higher voltage applied. 相似文献
822.
Suping Li Yuxia Jin Ping Tang Xiaodan Liu Xiaojun Chai Jinhua Dong Xuan Che Qinqin Zhou Meidi Ni Fan Jin 《Experimental biology and medicine (Maywood, N.J.)》2022,247(6):488
Among different types of congenital heart diseases, ventricular septal defect is the most frequently diagnosed type and is frequently missed in early prenatal screening programs. Herein, we explored the role of maternal serum-derived exosomes in detecting and predicting ventricular septal defect in fetuses in the early stage of pregnancy. A total of 104 pregnant women consisting of 52 ventricular septal defect cases and 52 healthy controls were recruited. TMT/iTRAQ proteomic analysis uncovered 15 maternal serum exosomal proteins, which showed differential expression between ventricular septal defect and control groups. Among these, four down-regulated proteins, lactoferrin, SBSN, DCD, and MBD3, were validated by Western blot. The protein lactoferrin was additionally verified by ELISA which was able to distinguish ventricular septal defects from controls with area under the ROC curve (AUC) 0.804 (p < 0.001). Our findings reveal that lactoferrin in maternal serum-derived exosomes may be a potential biomarker for non-invasive prenatal diagnosis of fetal ventricular septal defects. 相似文献
823.
Yuan Qin Wei Sun Zhihong Wang Wenwu Dong Liang He Ting Zhang Chengzhou Lv Hao Zhang 《Cell death & disease》2022,13(3)
Papillary thyroid carcinoma (PTC) is the main type of thyroid carcinoma. Despite the good prognosis, some PTC patients may deteriorate into more aggressive diseases, leading to poor survival. Molecular technology has been increasingly used in the diagnosis and treatment of thyroid carcinoma. In this study, we identified that RNA Binding Motif Protein 47 (RBM47) was downregulated in PTC tissues and cells, and overexpression of RBM47 could activate autophagy and inhibit proliferation in PTC cells. RBM47 promotes but can not bind directly to Forkhead Box O3 (FOXO3). FOXO3 activates Autophagy Related Gene 3 (ATG3), ATG5, and RBM47 to form a loop and promote autophagy. RBM47 can bind directly to and stabilized lncRNA Small Nucleolar RNA Host Gene 5 (SNHG5) to inhibit PTC cells proliferation and activate autophagy in vitro and in vivo. SNHG5 inhibits ubiquitination and degradation of FOXO3 by recruiting Ubiquitin Specific Peptidase 21 (USP21), then promotes the translocation of FOXO3 from cytoplasm to nucleus. Our study revealed the regulatory mechanism of RBM47/SNHG5/FOXO3 axis on cell proliferation and autophagy in PTC, which may provide valuable insight for the treatment of PTC.Subject terms: Oncogenes, Head and neck cancer 相似文献
824.
825.
Jong Taik Moon Sung Hoon Ha So Hyung Lee Tae Hui Kwon Chun Rim Oh Young Deuk Kim Jungahn Kim Dong Joon Choo Jae Yeol Lee 《Bioorganic & medicinal chemistry letters》2010,20(1):52-55
First total synthesis of methylgerambullone (MGB, 1) isolated from Glycosmis angustifolia was completed via a convergent route. The effect of MGB on the contractile responses of the isolated guinea-pig ileum induced by acetylcholine was investigated. As a result, it showed a potent relaxation rate (78.66 ± 4.30% at 100 mg/L) in a concentration-dependent manner on longitudinal smooth muscle contraction of isolated guinea-pig ileum induced by 1 μM acetylcholine. 相似文献
826.
827.
Up-regulation of apoptosis inhibitory protein IAP-2 by hypoxia. Hif-1-independent mechanisms 总被引:15,自引:0,他引:15
Dong Z Venkatachalam MA Wang J Patel Y Saikumar P Semenza GL Force T Nishiyama J 《The Journal of biological chemistry》2001,276(22):18702-18709
828.
Zhang Y Mattjus P Schmid PC Dong Z Zhong S Ma WY Brown RE Bode AM Schmid HH Dong Z 《The Journal of biological chemistry》2001,276(15):11775-11782
The sphingomyelin-ceramide pathway is an evolutionarily conserved ubiquitous signal transduction system that regulates many cell functions including apoptosis. Sphingomyelin (SM) is hydrolyzed to ceramide by different sphingomyelinases. Ceramide serves as a second messenger in mediating cellular effects of cytokines and stress. In this study, we find that acid sphingomyelinase (SMase) activity was induced by UVA in normal JY lymphoblasts but was not detectable in MS1418 lymphoblasts from Niemann-Pick type D patients who have an inherited deficiency of acid SMase. We also provide evidence that UVA can induce apoptosis by activating acid SMase in normal JY cells. In contrast, UVA-induced apoptosis was inhibited in MS1418 cells. Exogenous SMase and its product, ceramide (10-40 micrometer), induced apoptosis in JY and MS1418 cells, but the substrate of SMase, SM (20-80 micrometer), induced apoptosis only in JY cells. These results suggest that UVA-induced apoptosis by SM is dependent on acid SMase activity. We also provide evidence that induction of apoptosis by UVA may occur through activation of JNKs via the acid SMase pathway. 相似文献
829.
Abbott MB Dong WJ Dvoretsky A DaGue B Caprioli RM Cheung HC Rosevear PR 《Biochemistry》2001,40(20):5992-6001
Multidimensional heteronuclear magnetic resonance studies of the cardiac troponin C/troponin I(1-80)/troponin I(129-166) complex demonstrated that cardiac troponin I(129-166), corresponding to the adjacent inhibitory and regulatory regions, interacts with and induces an opening of the cardiac troponin C regulatory domain. Chemical shift perturbation mapping and (15)N transverse relaxation rates for intact cardiac troponin C bound to either cardiac troponin I(1-80)/troponin I(129-166) or troponin I(1-167) suggested that troponin I residues 81-128 do not interact strongly with troponin C but likely serve to modulate the interaction of troponin I(129-166) with the cardiac troponin C regulatory domain. Chemical shift perturbations due to troponin I(129-166) binding the cardiac troponin C/troponin I(1-80) complex correlate with partial opening of the cardiac troponin C regulatory domain previously demonstrated by distance measurements using fluorescence methodologies. Fluorescence emission from cardiac troponin C(F20W/N51C)(AEDANS) complexed to cardiac troponin I(1-80) was used to monitor binding of cardiac troponin I(129-166) to the regulatory domain of cardiac troponin C. The apparent K(d) for cardiac troponin I(129-166) binding to cardiac troponin C/troponin I(1-80) was 43.3 +/- 3.2 microM. After bisphosphorylation of cardiac troponin I(1-80) the apparent K(d) increased to 59.1 +/- 1.3 microM. Thus, phosphorylation of the cardiac-specific N-terminus of troponin I reduces the apparent binding affinity of the regulatory domain of cardiac troponin C for cardiac troponin I(129-166) and provides further evidence for beta-adrenergic modulation of troponin Ca(2+) sensitivity through a direct interaction between the cardiac-specific amino-terminus of troponin I and the cardiac troponin C regulatory domain. 相似文献
830.
Rozanova E. P. Borzenkov I. A. Tarasov A. L. Suntsova L. A. Dong Ch. L. Belyaev S. S. Ivanov M. V. 《Microbiology》2001,70(1):102-110
Thermophilic sulfate-reducing bacteria (SRB) oxidizing lactate, butyrate, and C12–C16
n-alkanes of oil at a temperature of 90°C were isolated from samples of water and oil originating from oil reservoirs of the White Tiger high-temperature oil field (Vietnam). At the same time, no thermophiles were detected in the injected seawater, which contained mesophilic microorganisms and was the site of low-temperature processes of sulfate reduction and methanogenesis. Thermophilic SRB were also found in samples of liquid taken from various engineering reservoirs used for oil storage, treatment, and transportation. These samples also contained mesophilic SRB, methanogens, aerobic oil-oxidizing bacteria, and heterotrophs. Rates of bacterial production of hydrogen sulfide varied from 0.11 to 2069.63 at 30°C and from 1.18 to 173.86 at 70°C g S/(l day); and those of methane production, varied from 58.4 to 100 629.8 nl CH4/(l day) (at 30°C). The sulfur isotopic compositions of sulfates contained in reservoir waters and of hydrogen sulfide of the accompanying gas indicate that bacterial sulfate reduction might be effective in the depth of the oil field. 相似文献