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1.
Sensors (Basel) ; 22(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35062652

RESUMO

Cameras are widely used in the detection and tracking of moving targets. Compared to target visual tracking using a single camera, cooperative tracking based on multiple cameras has advantages including wider visual field, higher tracking reliability, higher precision of target positioning and higher possibility of multiple-target visual tracking. With vast ocean and sea surfaces, it is a challenge using multiple cameras to work together to achieve specific target tracking and detection, and it will have a wide range of application prospects. According to the characteristics of sea-surface moving targets and visual images, this study proposed and designed a sea-surface moving-target visual detection and tracking system with a multi-camera cooperation approach. In the system, the technologies of moving target detection, tracking, and matching are studied, and the strategy to coordinate multi-camera cooperation is proposed. The comprehensive experiments of cooperative sea-surface moving-target visual tracking show that the method used in this study has improved performance compared with contrapositive methods, and the proposed system can meet the needs of multi-camera cooperative visual tracking of moving targets on the sea surface.


Assuntos
Processamento de Imagem Assistida por Computador , Movimento , Humanos
2.
Bioorg Chem ; 102: 104076, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32683180

RESUMO

A new series of derivatives characterized by the presence of the 3,4,5-trimethoxylbenzamide substituted benzofurans were synthesized and evaluated for antiproliferative activity against four cancer cell lines and one normal human cell line. Among them, derivative 6g with greatest cytotoxicity significantly inhibited the growth of MDA-MB-231, HCT-116, HT-29 and HeLa cell lines with IC50 values of 3.01, 5.20, 9.13, and 11.09 µM, respectively. Importantly, 6g possessed excellent selectivity over non-tumoral cell lines HEK-293 (IC50 > 30 µM). Moreover, mechanistic studies revealed that 6g induced HeLa cells arrested in G2/M phase in a concentration-dependent manner, and inhibited polymerization of tubulin via a consistent way with CA-4. In general, these observations suggest that 6g is a promising anti-cancer lead and is worth further investigation to generate potential antitumor agents.


Assuntos
Benzamidas/síntese química , Benzamidas/uso terapêutico , Polimerização/efeitos dos fármacos , Moduladores de Tubulina/uso terapêutico , Tubulina (Proteína)/química , Benzamidas/farmacologia , Desenho de Fármacos , Células HeLa , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Moduladores de Tubulina/farmacologia
3.
Bioorg Med Chem Lett ; 29(1): 22-27, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30448234

RESUMO

Based on our previous research, three series of new triazolylthioacetamides possessing 3,4,5-trimethoxyphenyl moiety were synthesized, and evaluated for antiproliferative activities and inhibition of tubulin polymerization. The most promising compounds 8b and 8j demonstrated more significant antiproliferative activities against MCF-7, HeLa, and HT-29 cell lines than our lead compound 6. Moreover, analogues 8f, 8j, and 8o manifested more potent antiproliferative activities against HeLa cell line with IC50 values of 0.04, 0.05 and 0.16 µM, respectively, representing 100-, 82-, and 25-fold improvements of the activity compared to compound 6. Furthermore, the representative compound, 8j, was found to induce significant cell cycle arrest at the G2/M phase in HeLa cell lines via a concentration-dependent manner. Meanwhile, compound 8b exhibited the most potent tubulin polymerization inhibitory activity with an IC50 value of 5.9 µM, which was almost as active as that of CA-4 (IC50 = 4.2 µM). Additionally, molecular docking analysis suggested that 8b formed stable interactions in the colchicine-binding site of tubulin.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Tioacetamida/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Polimerização/efeitos dos fármacos , Relação Estrutura-Atividade , Tioacetamida/síntese química , Tioacetamida/química , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química
4.
Sensors (Basel) ; 19(24)2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31817517

RESUMO

A portable capacitive sensor was designed to assess frying oil degradation by measuring the changes in electrical capacitance. An interdigital electrode (IDE) was designed to be implemented as the testing probe (as IDEs are resistive to parasitic capacitance), together with an adjacent capacitive chip Pcap01 and a further microprocessor STM32, which were used as the data-processing elements. Experimental results demonstrated that viscosity could be a useful frying oil quality indicator, and also proved a preliminary correlation between IDE capacitance and oils' total polar materials. This implies that IDE capacitance could be a suitable metric for conveniently assessing frying oil degradation. The designed capacitance sensor is light in weight, cost effective, and has excellent potential for simple, inexpensive, on-the-spot testing of the current quality of frying oil.

5.
Mol Cancer ; 17(1): 69, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29510730

RESUMO

BACKGROUND: Metabolic plasticity has been increasingly thought to be a determinant of tumor growth and metastasis. MACC1, a transcriptional regulator of MET, was recognized as an oncogene in gastric cancer (GC); however, its transcriptional or post-translational regulation was not clear. We previously reported the metabolic role of MACC1 in glycolysis to promote GC progression. MACC1-AS1 is the antisense lncRNA of MACC1, yet its function was previously unknown. METHODS: We profiled and analyzed the expression of MACC1-AS1 utilizing the TCGA database as well as in situ hybridization using 123 pairs of GC tissues and matched adjacent normal gastric mucosa tissues (ANTs). The biological role of MACC1-AS1 in cell growth and metastasis was determined by performing in vitro and in vivo functional experiments. Glycolysis and antioxidant capabilities were assayed to examine its metabolic function. Further, the specific regulatory effect of MACC1-AS1 on MACC1 was explored transcriptionally and post-transcriptionally. RESULTS: MACC1-AS1 was shown to be expressed significantly higher in GC tissues than in ANTs, which predicted poor prognosis in GC patients. MACC1-AS1 promoted GC cell proliferation and inhibited cell apoptosis under metabolic stress. Mechanistically, MACC1-AS1 stabilized MACC1 mRNA and post-transcriptionally augmented MACC1 expression. Further, MACC1-AS1 was shown to mediate metabolic plasticity through MACC1 upregulation and subsequent enhanced glycolysis and anti-oxidative capabilities, and this was suggested to be coordinated by the AMPK/Lin28 pathway. CONCLUSIONS: Elevated expression of MACC1-AS1 in gastric cancer tissues is linked to poor prognosis and promotes malignant phenotype upon cancer cells. MACC1-AS1 is elevated under metabolic stress and facilitates metabolic plasticity by promoting MACC1 expression through mRNA stabilization. Our study implicates lncRNA MACC1-AS1 as a valuable biomarker for GC diagnosis and prognosis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , RNA Antissenso , RNA Longo não Codificante , Proteínas de Ligação a RNA/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Fatores de Transcrição/genética , Adulto , Idoso , Biomarcadores Tumorais , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Progressão da Doença , Metabolismo Energético , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estabilidade de RNA , Transdução de Sinais , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Estresse Fisiológico , Transativadores
6.
Int J Cancer ; 142(12): 2578-2588, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29363109

RESUMO

Cetuximab resistance is a key barrier in treating metastatic colorectal cancer (mCRC). Targeting of metabolic resources import could resensitize drug-resistant cancer cells to anticancer treatments. Here we showed that the expression of the glutamine transporter solute carrier 1 family member 5 (SLC1A5) in clinical CRC samples of patients resisted to cetuximab was significantly higher than in those of patients responded to cetuximab. Inhibition of SLC1A5 by shRNA-mediated gene silencing or pharmacological inhibitor significantly suppressed the growth of CRC. Moreover, inhibition of SLC1A5 significantly enhanced the inhibitory efficacy of cetuximab on CRC proliferation both in vitro and in vivo. Mechanistically, SLC1A5 inhibition facilitated EGFR degradation through the ubiquitin-proteasome pathway, and decreased the expression of nuclear EGFR, both of which might have contribution to the improved response to cetuximab. This study provides the metabolic molecule SLC1A5 as a potential therapeutic target to increase the efficacy of cetuximab on CRC.


Assuntos
Sistema ASC de Transporte de Aminoácidos/metabolismo , Antineoplásicos Imunológicos , Cetuximab , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Antígenos de Histocompatibilidade Menor/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
BMC Cancer ; 18(1): 515, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720123

RESUMO

BACKGROUND: Gastric cancer is common in developing regions, and we hope to find out an economical but practical prognostic indicator. It was reported that pre-treatment peripheral neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), as well as differentiation status, were associated with cancer progression. Hence, we introduced a novel combined Neutrophil/platelet/lymphocyte/differentiation Score (cNPLDS) to improve the prediction value of palliative chemotherapeutic response in advanced gastric cancer. METHODS: According to statistical sample size estimation, 136 primary diagnosed unresectable advanced ptaients were included for a retrospective study. The follow-up end-point was progression free survival (PFS) during the first-line palliative chemotherapy. Differentiation stratified patients into well, medium and poor groups by score 1 to 3, while patients with neither elevated NLR and PLR, only one elevated, or both elevated were of the combined NLR-PLR score (cNPS) 1 to 3, respectively. The cNPLDS was calculated by multiplying the tumor differentiation score and cNPS. RESULTS: Determined by the receiver operating characteristic (ROC) curve, the optimal cut-off points for NLR and PLR were 3.04 and 223. Through univariate analysis and survival analysis, poor differentiation, high NLR, high PLR, high cNPS, and high cNPLDS respectively indicated inferior PFS during the first-line palliative chemotherapy. Patients were furhter classified into low to high risk groups by cNPLDS. Groups of elevated NLR, PLR, cNPS, and cNPLDS showed lower disease control rate. Compared to other parameters, cNPLDS significantly improved the accuracy in predicing the first-progression. CONCLUSIONS: This study indicates that the novel parameter cNPLDS is superior to NLR or PLR alone, or even cNPS, in predicting the first-line chemosensitivity in advanced gastric cancer.


Assuntos
Plaquetas/imunologia , Linfócitos/imunologia , Neutrófilos/imunologia , Neoplasias Gástricas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Biomarcadores Tumorais/análise , Plaquetas/patologia , Diferenciação Celular/imunologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Feminino , Humanos , Contagem de Linfócitos , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Contagem de Plaquetas , Prognóstico , Intervalo Livre de Progressão , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia
8.
BMC Complement Altern Med ; 16: 56, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26852136

RESUMO

BACKGROUND: Xue-Fu-Zhu-Yu decoction (XFZYD), Tian-Ma-Gou-Teng-Yin (TMGTY) and Wen-Dan decoction (WDD) are Chinese herbal formulas used to treat hypertension and cardiovascular diseases in traditional Chinese medicine (TCM). The goal of our study is to determine if XFZYD, TMGTY or WDD treatment ameliorated myocardial fibrosis in spontaneously hypertensive rats (SHRs) and to identify the mechanisms underlying any beneficial effects observed during the courses of the investigation. METHODS: Forty-five 12-week-old male spontaneously hypertensive rats and five age-matched male Wistar-Kyoto control rats were studied for 16 weeks. Each day 6 g∙kg(-1) or 12 g∙kg(-1) of XFZYD, TMGTY or WDD was orally administered at the indicated dose, and the systolic blood pressure (SBP) of all rats was measured using the tail-cuff method. Collagen levels were measured via hydroxyproline content assays and histological examination. Transforming growth factor beta-1 (TGF-ß1) protein levels were determined via immunhistochemical and Western blot analysis. TGF-ß1 mRNA levels were assessed using real-time reverse transcription polymerase chain reaction. RESULTS: Systolic blood pressure was unaffected, but collagen and TGF-ß1 levels in SHRs treated with captopril and XFZYD (12 g∙kg(-1)) were significantly reduced when compared with untreated control SHRs. Administration of 12 g∙kg(-1) XFZYD increased myocardial cell protection and decreased TGF-ß1 mRNA and protein expression when compared with the other SHR treatment groups. CONCLUSIONS: XFZYD treatment demonstrated a superior ability to reverse myocardial fibrosis when compared with WDD or TMGTY treatment in SHRs. XFZYD also decreased TGF-ß1 mRNA and protein expression, suggesting that the TGF-ß1 signaling pathway plays a role in the therapeutic effects of XFZYD treatment.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Fibrose Endomiocárdica/tratamento farmacológico , Hipertensão/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Fibrose Endomiocárdica/patologia , Hidroxiprolina/metabolismo , Masculino , Ratos , Ratos Endogâmicos WKY , Fator de Crescimento Transformador beta/metabolismo
9.
ACS Appl Mater Interfaces ; 15(37): 44433-44443, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37682724

RESUMO

We explored the electrical activity and extremes inside individual suspended zinc oxide (ZnO) nanowires (NWs) (diameter: 50-550 nm, length: 5-50 µm) subjected to high forward bias-induced Joule heating using two-terminal current-voltage measurements. NWs were isolated using a reproducible nanometrology technique, employing a nanomanipulator inside a scanning electron microscope. Schottky behavior is observed between installed tips and ZnO NW. The suspended ZnO NWs exhibited an average electrical resistivity ρ (approximately 2.3 × 10-2 Ω cm) and a high electron density n (exceeding 1.89 × 1018 cm-3), comparable to that of InP NWs, GaN NWs, and InAs NWs (1018∼1019 cm-3), suggesting the potential to drive advancements in high-performance NW devices. A maximum breakdown current density (JBD) of ∼0.14 MA/cm2 and a maximum breakdown power density (PBD) of 6.93 mW/µm3 were obtained, both of which are higher than substrate-bound ZnO NWs and consistent with previously reported results obtained from probed ZnO NWs grown vertically on the substrate. Moreover, we discovered that NWs experienced thermal breakdown due to Joule heating and exploited this breakdown mechanism to further investigate the temperature distribution along the ZnO NWs, as well as its dependence on the electrical properties and thermal conductance of contact electrodes. Thermal conductance was determined to be ∼0.4 nW K-1 and ∼1.66 pW K-1 at the tungsten(W)-ZnO NW and platinum(Pt)-ZnO NW contacts, respectively. In addition, we measured the elastic modulus (130-171 GPa), which closely approximated bulk values. We also estimated the nanoindentation hardness to be between 5 and 10 GPa. This work provides valuable insights into the electrical activity and extreme mechanisms, thus providing a better understanding of the potentials and limitations associated with utilizing suspended NWs in 3D nanodevices.

10.
Micromachines (Basel) ; 13(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35744441

RESUMO

Using the skeletal structure and muscle distribution of the hind limbs of a jumping kangaroo as inspiration, a bionic jumping leg was designed with pneumatic artificial muscles (PAMs) as actuators. Referring to the position of biarticular muscles in kangaroos, we constructed a bionic joint using biarticular and monoarticular muscle arrangements. At the same time, the problem of the joint rotation angle limitations caused by PAM shrinkage was solved, and the range of motion of the bionic joint was improved. Based on the output force model of the PAM, we established a dynamic model of the bionic leg using the Lagrange method. In view of the coupling problem caused by the arrangement of the biarticular muscle, an extended state observer was used for decoupling. The system was decoupled into two single-input and single-output systems, and angle tracking control was carried out using active disturbance rejection control (ADRC). The simulation and experimental results showed that the ADRC algorithm had a better decoupling effect and shorter adjustment time than PID control. The jumping experiments showed that the bionic leg could jump with a horizontal displacement of 320 mm and a vertical displacement of 150 mm.

11.
Micromachines (Basel) ; 12(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671034

RESUMO

ZnO nanomaterials have been widely used in micro/nano devices and structure due to special mechanical/electrical properties, and its characterization is still deficient and challenging. In this paper, ZnO nanomaterials, including nanorod and nanowire are characterized by atomic force microscope (AFM) and nanomanipulator embedded in scanning electron microscope (SEM) respectively, which can manipulate and observe simultaneously, and is efficient and cost effective. Surface morphology and mechanical properties were observed by AFM. Results showed that the average Young's modulus of ZnO nanorods is 1.40 MPa and the average spring rate is 0.08 N/m. Electrical properties were characterized with nanomanipulator, which showed that the ZnO nanomaterial have cut-off characteristics and good schottky contact with the tungsten probes. A two-probe strategy was proposed for piezoelectric property measurement, which is easy to operate and adaptable to multiple nanomaterials. Experiments showed maximum voltage of a single ZnO nanowire is around 0.74 mV. Experiment criteria for ZnO manipulation and characterization were also studied, such as acceleration voltage, operation duration, sample preparation. Our work provides useful references for nanomaterial characterization and also theoretical basis for nanomaterials application.

12.
Eur J Med Chem ; 220: 113449, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33895499

RESUMO

By removing 5-methyl and 6-acetyl groups in our previously reported compound 3, we designed a series of novel 2,7-diaryl-[1,2,4]triazolo[1,5-a]pyrimidine derivatives as potential tubulin polymerization inhibitors. Among them, compound 5e displayed low nanomolar antiproliferative efficacy on HeLa cells which was 166-fold higher than the lead analogue 3. Interestingly, 5e displayed significant selectivity in inhibiting cancer cells over HEK-293 (normal human embryonic kidney cells). In addition, 5e dose-dependently arrested HeLa in G2/M phase through the alterations of the expression levels of p-cdc2 and cyclin B1, and caused HeLa cells apoptosis by regulation of expressions of cleaved PARP. Further evidence demonstrated that 5e effectively inhibited tubulin polymerization and was 3-fold more powerful than positive control CA-4. Moreover, molecular docking analysis indicated that 5e overlapped well with CA-4 in the colchicine-binding site. These studies demonstrated that 2,7-diaryl-[1,2,4]triazolo[1,5-a]pyrimidine skeleton might be used as the leading unit to develop novel tubulin polymerization inhibitors as potential anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Pirimidinas/farmacologia , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Polimerização/efeitos dos fármacos , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/química
13.
Acta Pharmacol Sin ; 31(8): 953-62, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20686520

RESUMO

AIM: To investigate whether geniposide, an iridoid glucoside extracted from gardenia jasminoides ellis fruits, inhibits cell adhesion to human umbilical vein endothelial cells (HUVECs) induced by high glucose and its underlying mechanisms. METHODS: HUVECs were isolated from human umbilical cords and cultured. The adhesion of monocytes to HUVECs was determined using fluorescence-labeled monocytes. The mRNA and protein levels of vascular cell adhesion molecule-1 (VCAM-1) and endothelial selectin (E-selectin) were measured using real-time RT-PCR and ELISA. Reactive oxygen species (ROS) production was measured using a fluorescent probe. The amounts of nuclear factor-kappa B (NF-kappaB) and inhibitory factor of NF-kappaB (IkappaB) were determined using Western blot analysis. The translocation of NF-kappaB from the cytoplasm to the nucleus was determined using immunofluorescence. RESULTS: Geniposide (10-20 mumol/L) inhibited high glucose (33 mmol/L)-induced adhesion of monocytes to HUVECs in a dose-dependent manner. This compound (5-40 mumol/L) also inhibited high glucose-induced expression of VCAM-1 and E-selectin at the gene and protein levels. Furthermore, geniposide (5-20 micromol/L) decreased ROS production and prevented IkappaB degradation in the cytoplasm and NF-kappaB translocation from the cytoplasm to the nucleus in HUVECs. CONCLUSION: Geniposide inhibits the adhesion of monocytes to HUVECs and the expression of CAMs induced by high glucose, suggesting that the compound may represent a new treatment for diabetic vascular injury. The mechanism underlying this inhibitory effect may be related to the inhibition of ROS overproduction and NF-kappaB signaling pathway activation by geniposide.


Assuntos
Gardenia/química , Iridoides/farmacologia , NF-kappa B/metabolismo , Adesão Celular , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Glucose/farmacologia , Humanos , Iridoides/administração & dosagem , Iridoides/isolamento & purificação , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo
14.
Phytother Res ; 24(2): 219-24, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19610026

RESUMO

AIM: Hepatic glycogen phosphorylase (GP) and glucose-6-phosphatase (G6Pase) are important in control of blood glucose homeostasis, and are considered to be potential targets for antidiabetic drugs. Astragaloside IV has been reported to have a hypoglycemic effect. However, the biochemical mechanisms by which astragaloside IV regulates hepatic glucose-metabolizing enzymes remain unknown. The present study examines whether GP and G6Pase mediate the hypoglycemic effect of astragaloside IV. METHODS: Type 2 diabetic mice were treated with astragaloside IV for 2 weeks. Blood glucose and insulin levels were measured by a glucometer and the ELISA method, respectively. Total cholesterol (TC) and triglyceride (TG) levels were determined using Labassay kits. Activities of hepatic GP and G6Pase were measured by the glucose-6-phosphate dehydrogenase-coupled reaction. The mRNA and protein levels of both enzymes were determined by real-time RT-PCR and Western blotting. RESULTS: Astragaloside IV at 25 and 50 mg/kg significally decreased the blood glucose, TG and insulin levels, and inhibited the mRNA and protein expression as well as enzyme activity of GP and G6Pase in diabetic mice. CONCLUSIONS: Astragaloside IV exhibited a hypoglycemic effect in diabetic mice. The hypoglycemic effect of this compound may be explained, in part, by its inhibition of hepatic GP and G6Pase activities.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Glucose-6-Fosfatase/metabolismo , Glicogênio Fosforilase/metabolismo , Hipoglicemiantes/farmacologia , Fígado/enzimologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Diabetes Mellitus Experimental/enzimologia , Medicamentos de Ervas Chinesas/farmacologia , Insulina/sangue , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Estreptozocina , Triglicerídeos/sangue
15.
Acta Pharmacol Sin ; 30(2): 202-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19122671

RESUMO

AIM: Hepatic glycogen phosphorylase (GP) and glucose-6-phosphatase (G6Pase) play an important role in the control of blood glucose homeostasis and are proposed to be potential targets for anti-diabetic drugs. Geniposide is an iridoid glucoside extracted from Gardenia jasminoides Ellis fruits and has been reported to have a hypoglycemic effect. However, little is known about the biochemical mechanisms by which geniposide regulates hepatic glucose-metabolizing enzymes. The present study investigates whether the hypoglycemic effect of geniposide is mediated by GP or G6Pase. METHODS: Type 2 diabetic mice, induced by a high-fat diet and streptozotocin injection, were treated with or without geniposide for 2 weeks. Blood glucose levels were monitored by a glucometer. Insulin concentrations were analyzed by the ELISA method. Total cholesterol (TC) and triglyceride (TG) levels were measured using Labassay kits. Activities of hepatic GP and G6Pase were measured by glucose-6-phosphate dehydrogenase-coupled reaction. Real-time RT-PCR and Western blotting were used to determine the mRNA and protein levels of both enzymes. RESULTS: Geniposide (200 and 400 mg/kg) significantly decreased the blood glucose, insulin and TG levels in diabetic mice in a dose-dependent manner. This compound also decreased the expression of GP and G6Pase at mRNA and immunoreactive protein levels, as well as enzyme activity. CONCLUSION: Geniposide is an effective hypoglycemic agent in diabetic mice. The hypoglycemic effect of this compound may be mediated, at least in part, by inhibiting the GP and G6Pase activities.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Dieta , Gorduras na Dieta , Glucose-6-Fosfatase/metabolismo , Glicogênio Fosforilase/metabolismo , Hipoglicemiantes/metabolismo , Iridoides/metabolismo , Animais , Glicemia/metabolismo , Colesterol/sangue , Glucose-6-Fosfatase/genética , Glicogênio Fosforilase/genética , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Iridoides/administração & dosagem , Iridoides/química , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Distribuição Aleatória , Triglicerídeos/sangue
16.
Acta Pharmacol Sin ; 30(5): 589-96, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19349964

RESUMO

AIM: Exocytosis of endothelial Weibel-Palade bodies, which contain von Willebrand factor (VWF), P-selectin and other modulators, plays an important role in both inflammation and thrombosis. The present study investigates whether genipin, an aglycon of geniposide, inhibits endothelial exocytosis. METHODS: Human umbilical vein endothelial cells (HUVECs) were isolated from umbilical cords and cultured. The concentration of VWF in cell supernatants was measured using an ELISA Kit. P-selectin translocation on the cell surface was analyzed by cell surface ELISA. Cell viability was measured using a Cell Counting Kit-8. Mouse bleeding times were measured by amputating the tail tip. Western blot analysis was used to determine the amount of endothelial nitric oxide synthase (eNOS) and phospho-eNOS present. Nitric oxide (NO) was measured in the cell supernatants as nitrite using an NO Colorimetric Assay. RESULTS: Genipin inhibited thrombin-induced VWF release and P-selectin translocation in HUVECs in a dose- and time-dependent manner. The drug had no cytotoxic effect on the cells at the same doses that were able to inhibit exocytosis. The functional study that demonstrated that genipin inhibited exocytosis in vivo also showed that genipin prolonged the mouse bleeding time. Furthermore, genipin activated eNOS phosphorylation, promoted enzyme activation and increased NO production. L-NAME, an inhibitor of NOS, reversed the inhibitory effects of genipin on endothelial exocytosis. CONCLUSION: Genipin inhibits endothelial exocytosis in HUVECs. The mechanism by which this compound inhibits exocytosis may be related to its ability to stimulate eNOS activation and NO production. Our findings suggest a novel anti-inflammatory mechanism for genipin. This compound may represent a new treatment for inflammation and/or thrombosis in which excess endothelial exocytosis plays a pathophysiological role.


Assuntos
Células Endoteliais/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Iridoides/farmacologia , Óxido Nítrico/metabolismo , Veias Umbilicais/citologia , Animais , Tempo de Sangramento , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/fisiologia , Feminino , Humanos , Glicosídeos Iridoides , Camundongos , Selectina-P/metabolismo , Gravidez , Transporte Proteico/efeitos dos fármacos , Fator de von Willebrand/metabolismo
17.
Micromachines (Basel) ; 10(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817762

RESUMO

Reports on measurements of the rotational velocity by using giant magnetoimpedance sensors are rarely seen. In this study, a rotational-velocity sensing system based on giant magnetoimpedance (GMI) effect was established to measure rotational velocities of brushless direct-current motors. Square waves and sawtooth waves were observed due to the rotation of the shaft. We also found that the square waves gradually became sawtooth waves with increasing the measurement distance and rotational velocity. The GMI-based rotational-velocity measurement results (1000-4300 r/min) were further confirmed using the Hall sensor. This GMI sensor is capable of measuring ultrahigh rotational velocity of 84,000 r/min with a large voltage response of 5 V, even when setting a large measurement distance of 9 cm. Accordingly, the GMI sensor is very useful for sensitive measurements of high rotational velocity.

18.
Cancer Immunol Res ; 7(5): 737-750, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30842092

RESUMO

Tumor microenvironment (TME) cells constitute a vital element of tumor tissue. Increasing evidence has elucidated their clinicopathologic significance in predicting outcomes and therapeutic efficacy. Nonetheless, no studies have reported a systematic analysis of cellular interactions in the TME. In this study, we comprehensively estimated the TME infiltration patterns of 1,524 gastric cancer patients and systematically correlated the TME phenotypes with genomic characteristics and clinicopathologic features of gastric cancer using two proposed computational algorithms. Three TME phenotypes were defined, and the TMEscore was constructed using principal component analysis algorithms. The high TMEscore subtype was characterized by immune activation and response to virus and IFNγ. Activation of transforming growth factor ß, epithelial-mesenchymal transition, and angiogenesis pathways were observed in the low TMEscore subtype, which are considered T-cell suppressive and may be responsible for significantly worse prognosis in gastric cancer [hazard ratio (HR), 0.42; 95% confidence interval (CI), 0.33-0.54; P < 0.001]. Multivariate analysis revealed that the TMEscore was an independent prognostic biomarker, and its value in predicting immunotherapeutic outcomes was also confirmed (IMvigor210 cohort: HR, 0.63; 95% CI, 0.46-0.89; P = 0.008; GSE78220 cohort: HR, 0.25; 95% CI, 0.07-0.89; P = 0.021). Depicting a comprehensive landscape of the TME characteristics of gastric cancer may, therefore, help to interpret the responses of gastric tumors to immunotherapies and provide new strategies for the treatment of cancers.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Microambiente Tumoral/genética , Algoritmos , Humanos , Imunoterapia , Fenótipo , Prognóstico , Neoplasias Gástricas/patologia
19.
Micromachines (Basel) ; 10(10)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581655

RESUMO

Micro/nano-manipulation is the fabrication of particular constructs on devices at the micro/nano-scale. Precise manipulation of microparticles is one of the key technological difficulties in manufacturing micro/nano-scale components. Based on scanning electron microscopy and nanomanipulator, this paper adopts a direct push method to operate randomly distributed microparticles into ordered structures. A two-probe interaction strategy is proposed to enable microparticle movements in all directions efficiently and avoid scratching the substrate surface. To overcome the uncertainties in micromanipulation, a virtual nano-hand strategy was also implemented: long-range advance of each microparticle is realized by multiple single-step pushes, whose trajectory is theoretically analyzed. The pushes are well programmed to imitate effects of a more powerful and determined hand. Experimental results show that the theoretical single-step motion trajectory is in line with actual operation, and the proposed strategy can ensure precise operation of the microparticles in all directions and improve reliability and effectiveness of operation.

20.
Zhong Yao Cai ; 31(6): 847-50, 2008 Jun.
Artigo em Zh | MEDLINE | ID: mdl-18998566

RESUMO

OBJECTIVE: To investigate the anti-HIV effects of Eucommia ulmoides Oliver, so as to provide experimental basis for searching a new efficacious drug for treatment of AIDS. METHODS: Using phytochemistry to isolate compounds from Eucommia ulmoides Oliver, the inhibitory activity of Samples on the HIV gp41 six-helix bundle formation was determined by a modified sandwich ELISA and PAGE. RESULTS: The Samples from Eucommia ulmoides Oliver had potent inhibitory activity on the HIV gp41 six-helix bundle formation. CONCLUSION: Eucommia uloides Oliver can inhibit HIV by targeting HIV gp41.


Assuntos
Fármacos Anti-HIV/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Eucommiaceae/química , Proteína gp41 do Envelope de HIV/efeitos dos fármacos , Animais , Fármacos Anti-HIV/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática/métodos , Inibidores da Fusão de HIV/farmacologia , Casca de Planta/química , Plantas Medicinais/química , Tecnologia Farmacêutica/métodos
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