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OBJECTIVES: To study the role and mechanism of platelet-derived growth factor BB (PDGF-BB) on platelet production in Kawasaki disease (KD) mice and human megakaryocytic Dami cells through in vitro and invivo experiments. METHODS: ELISA was used to measure the expression of PDGF in the serum of 40 children with KD and 40 healthy children. C57BL/6 mice were used to establish a model of KD and were then randomly divided into a normal group, a KD group, and an imatinib group (30 mice in each group). Routine blood test was performed for each group, and the expression of PDGF-BB, megakaryocyte colony forming unit (CFU-MK), and the megakaryocyte marker CD41 were measured. CCK-8, flow cytometry, quantitative real-time PCR, and Western blot were used to analyze the role and mechanism of PDGF-BB in platelet production in Dami cells. RESULTS: PDGF-BB was highly expressed in the serum of KD children (P<0.001). The KD group had a higher expression level of PDGF-BB in serum (P<0.05) and significant increases in the expression of CFU-MK and CD41 (P<0.001), and the imatinib group had significant reductions in the expression of CFU-MK and CD41 (P<0.001). In vitro experiments showed that PDGF-BB promoted Dami cell proliferation, platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). Compared with the PDGF-BB group, the combination group (PDGF-BB 25 ng/mL + imatinib 20 µmol/L) had significantly lower levels of platelet production, mRNA expression of PDGFR-ß, and protein expression of p-Akt (P<0.05). CONCLUSIONS: PDGF-BB may promote megakaryocyte proliferation, differentiation, and platelet production by binding to PDGFR-ß and activating the PI3K/Akt pathway, and the PDGFR-ß inhibitor imatinib can reduce platelet production, which provides a new strategy for the treatment of thrombocytosis in KD.
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Síndrome de Linfonodos Mucocutâneos , Trombocitose , Criança , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Becaplermina , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Trombocitose/tratamento farmacológico , Trombocitose/etiologia , RNA MensageiroRESUMO
Cleaning robot has the highest penetration rate among the service robots. This paper proposes a high-efficiency mechanism for an intelligent cleaning robot automatically returns to charging in a short time when the power is insufficient. The proposed mechanism initially combines the robot's own motor encoder with neural network linear regression to calculate the moving distance and rotation angle for the location estimation of the robot itself. At the same time, a self-rotating camera is applied to scan the number of infrared spots on the docking station to find the location of the docking station so that the cleaning robot returns to charging properly in two stages, existing infrared range and extended infrared range. In addition, six-axis acceleration and ultrasound are both applied to deal with the angle error that is caused by collision. Experimental results show that the proposed recharging mechanism significantly improves the efficiency of recharging.
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Li3V2(PO4)3 (LVP) particles dispersed in different inorganic carbons (LVP@C) have been successfully synthesized via an in situ synthesis method. The inorganic carbon materials with different dimensions including zero-dimensional Super P (SP) nanospheres, one-dimensional carbon nanotubes (CNTs), two-dimensional graphene nanosheets, and three-dimensional graphite particles. The effects of carbon dimensions on the structure, morphology, and electrochemical performance of LVP@C composites have been systematically investigated. The carbon materials can maintain their original morphology even after oxidation (by NH4VO3) and high-temperature sintering (850 °C). LVP@CNT exhibits the best electrochemical performances among all of the samples. At an ultrahigh discharge rate of 100C, it presents a discharge capacity of 91.94 mAh g(-1) (69.13% of its theoretical capacity) and maintains 79.82% of its original capacity even after 382 cycles. Its excellent electrochemical performance makes LVP@CNT a promising cathode candidate for lithium-ion batteries.
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LC-MS/MS is a promising analytical platform for the quantification of recombinant therapeutic proteins in biological fluids for pharmacokinetic (PK) studies. Herein, an absolute quantification method based on LC-MS/MS technique was developed to quantify endostar, which is modified from the recombinant human endostatin by adding a nine-amino acid sequence (MGGSHHHHH) at the N-terminal. A reproducible three-step analytical procedure was adopted: (1) Ni(2+) Sepharose was used to selectively extract endostar; (2) the signature peptide "TEAPSATGQASSLLGGR" (m/z 802.3(2+)-651.8(2+)) of endostar and a synthetic peptide "TEAPSATGQVSSLLGGR" (m/z 816.9(2+)-666.4(2+)) as internal standard (IS) were selected and analyzed in the multiple reaction monitoring (MRM) mode; (3) the proposed method was validated and applied to the pharmacokinetic study of endostar. The lower limit of quantification (LLOQ) for quantifying endostar was 50 ng/ml and this method is linear over 50-10,000 ng/ml. The accuracy was between 85% and 115%, and the intra-batch and inter-batch analytic precision and accuracy were below 15%. This LC-MS/MS approach was validated for the application to the pharmacokinetic study of endostar in rats.
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Inibidores da Angiogênese/sangue , Inibidores da Angiogênese/farmacocinética , Cromatografia Líquida , Endostatinas/sangue , Endostatinas/farmacocinética , Espectrometria de Massas em Tandem , Inibidores da Angiogênese/administração & dosagem , Animais , Calibragem , Cromatografia Líquida/normas , Estabilidade de Medicamentos , Endostatinas/administração & dosagem , Feminino , Humanos , Injeções Intravenosas , Limite de Detecção , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacocinética , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sefarose/análogos & derivados , Sefarose/química , Espectrometria de Massas em Tandem/normasRESUMO
Freshwater crabs and snails were collected from Ninghai County in Zhejiang Province, and examined respectively for Paragonimus metacercariae and cercariae. Among 97 freshwater crabs found, the prevalence was 11.3% (11/97) with a mean intensity of 1 metacercariae per crab. It was 10.2% (5/49) and 20.2% (4/20) in the groups weighted 5-15 g and 15-25 g respectively, with an average intensity of 1, and no metacercariae were found in weight group of 25-35 g. Two positive crabs were found from 20 crabs with a low weight (< 5 g). Male to female crabs ratio was 2.5:1, and there was no significant difference in prevalence between males [12.7%(7/55)] and females [9.1% (2/22)]. No cercariae or metacercariae were found in 200 snails (Semisulcospira libertino).
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Braquiúros/parasitologia , Paragonimíase/epidemiologia , Paragonimus , Caramujos/parasitologia , Animais , China/epidemiologia , Feminino , Água Doce , Interações Hospedeiro-Parasita , Masculino , Paragonimíase/parasitologiaRESUMO
AIM: To explore the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes. METHODS: Experimental animals were divided into the plain control group(control) and simulated altitude hypoxia group (altitude). The AC impedance of mouse erythrocytes was measured with the Agilent 4294A impedance analyzer, the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes was observed by cell dielectric spectroscopy, Cole-Cole plots, loss factor spectrum, loss tangent spectrum, and curve fitting analysis of Cole-Cole equation. RESULTS: After mice were exposed to hypoxia at simulated 5000 m altitude for 4 weeks, permittivity at low frequency (epsilonl) and dielectric increment (deltaepsilon) increased 57% and 59% than that of control group respectively, conductivity at low frequency (kappal) and conductivity at high frequency (kappah) reduced 49% and 11% than that of control group respectively. CONCLUSION: The simulated altitude hypoxia could arise to increase dielectric capability and depress conductive performance on mouse erythrocytes.