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1.
Sci Rep ; 13(1): 6101, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055539

RESUMEN

Solar flares are one of the severest solar activities that have important effects on near-Earth space. Previous studies have shown that flight arrival delays increase as a result of solar flares, but the intrinsic mechanism behind this relationship is still unknown. In this study, we conducted a comprehensive analysis of flight departure delays during 57 solar X-ray events by using a huge amount of flight data (~ 5 × 106 records) gathered over a 5-year period. It is found that the average flight departure delay time during solar X-ray events increased by 20.68% (7.67 min) compared to quiet periods. Our analysis also revealed apparent time and latitude dependencies, with flight delays being more serious on the dayside than on the nightside and longer (shorter) delays tending to occur in lower (higher) latitude airports during solar X-ray events. Furthermore, our results suggest that the intensity of solar flares (soft X-ray flux) and the Solar Zenith Angle directly modulate flight departure delay time and delay rate. These results indicate that communication interferences caused by solar flares directly affect flight departure delays. This work expands our conventional understanding of the impacts of solar flares on human society and provides new insights for preventing or coping with flight delays.

2.
Sci Rep ; 13(1): 3246, 2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828884

RESUMEN

Although the sun is really far away from us, some solar activities could still influence the performance and reliability of space-borne and ground-based technological systems on Earth. Those time-varying conditions in space caused by the sun are also called solar storm or space weather. It is known that aviation activities can be affected during solar storms, but the exact effects of space weather on aviation are still unclear. Especially how the flight delays, the top topic concerned by most people, will be affected by space weather has never been thoroughly researched. By analyzing huge amount of flight data (~ 4 × 106 records), for the first time, we quantitatively investigate the flight delays during space weather events. It is found that compared to the quiet periods, the average arrival delay time and 30-min delay rate during space weather events are significantly increased by 81.34% and 21.45% respectively. The evident negative correlation between the yearly flight regularity rate and the yearly mean total sunspot number during 22 years also confirms such correlation. Further studies show that the flight delay time and delay rate will monotonically increase with the geomagnetic field fluctuations and ionospheric disturbances. These results indicate that the interferences in communication and navigation during space weather events may be the most probable reason accounting for the increased flight delays. The above analyses expand the traditional field of space weather research and could also provide us with brand new views for improving the flight delay predications.

3.
Eur Rev Med Pharmacol Sci ; 22(18): 5899-5905, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30280770

RESUMEN

OBJECTIVE: Hepatocarcinoma is a great threat to global health. MicroRNA-23a was suggested to regulate growth and apoptosis in certain cell lines. Our study was focused on growth, proliferation, and apoptosis of hepatocarcinoma cell line MHCC97H under the influence of microRNA-23a, and explored the mechanism of pro-apoptosis microRNA-23a. MATERIALS AND METHODS: MicroRNA-23a and control microRNA (scramble miRNA, for short as miRNA) were synthesized with the routine protocol. Lipofection transfection was performed in hepatocarcinoma cell line MHCC97H. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, caspase-3 activity detection, and flow cytometry were performed to examine growth, proliferation, and apoptosis of hepatocarcinoma cell line MHCC97H, respectively. Kidney inhibitor of apoptosis protein (KIAP) and small interfere RNA (siRNA) was synthesized for inhibition of KIAP. KIAP plasmid was established for activation of KIAP. Western blot was performed to examine the protein expression of KIAP and caspase protein family after transfection of KIAP siRNA or KIAP plasmid. RESULTS: Compared with miRNA transfection, microRNA-23a transfection significantly reduced the growth of MHCC97H cells, and decreased the expression of KIAP (p < 0.05). Enhanced translocation of phosphatidylserine and activation of caspase-3 were observed in microRNA-23a transfection cells. Moreover, inhibition of KIAP enhanced the pro-apoptosis effect of microRNA-23a, while activation of KIAP abrogated pro-apoptosis effect of microRNA-23a. CONCLUSIONS: MicroRNA-23a inhibits growth and proliferation of MHCC97H cells, and induces apoptosis of MHCC97H cells via down-regulating KIAP. KIAP could be a potential therapeutic target for hepatocarcinoma treatment.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/genética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteínas de Neoplasias/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Apoptosis , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis/genética , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/genética
5.
Eur Rev Med Pharmacol Sci ; 21(18): 3982, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29028108

RESUMEN

The article "Effect of VEGF on neuronal degeneration and interaction between Alzheimer's disease biomarkers" by H.-C. Yuan, C.-W. Jiang, L.-Y. Hou, Y.-B. Lv, X.-Z. Feng, L.-F. Guo, G. Sun, K. Liu, Y.-J. Liu, B. Xu, C.-Y. Wang, published in Eur Rev Med Pharmacol Sci 2017; 21 (16): 3649-3657 has been withdrawn.

7.
Eur Rev Med Pharmacol Sci ; 21(10): 2385-2391, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28617551

RESUMEN

OBJECTIVE: The lung adenocarcinoma is a type of lung cancer. This research is to investigate the effects of miR-222 on the proliferation, migration and invasion of the lung adenocarcinoma cells. MATERIALS AND METHODS: At the beginning, MiR-222 and the controls were transfected to the lung adenocarcinoma cell line A549 for CCK-8 proliferation, transwell migration and Matrigel invasion, and then observed the effect of miR-222 on the proliferation, migration and invasion of lung adenocarcinoma cells. The miR-222 target was regulated by ETS1 downwards to participate in the regulation of the process by using the luciferase reporter assay, the Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) and the Western blotting. RESULTS: According to CCK-8 proliferation assay, the Transwell migration and the Matrigel invasion assay, it discovered that MiR-222 can promote the proliferation, migration and invasion of the lung adenocarcinoma cells. Luciferase reporter assay, RT-qPCR and Western blot assay showed that miR-222 could regulate the expression of ETS1 downwards and ETS1 participated in the regulation of the process CONCLUSIONS: ETS1 promotes proliferation, migration and invasion of lung adenocarcinoma cells by targeting the regulated miR-222 downwards.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Pulmonares/patología , MicroARNs/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma del Pulmón , Recuento de Células , Línea Celular Tumoral , Proliferación Celular , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , MicroARNs/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Transfección
9.
Zhongguo Yi Liao Qi Xie Za Zhi ; 25(6): 328-30, 341, 2001 Nov.
Artículo en Chino | MEDLINE | ID: mdl-12583263

RESUMEN

Our newly-designed computer-controlled equipment for delivering volatile anesthetic agent uses the subminiature singlechip processor as the central controlling unit. The variables, such as anesthesia method, anesthetic agent, the volume of respiratory loop, age of patient, sex, height, weight, environment temperature and the grade of ASA are all input from the keyboard. The anesthetic dosage, calculated by the singlechip processor, is converted into the signals controlling the pump to accurately deliver anesthetic agent into respiratory loop. We have designed an electrocircuit for the equipment to detect the status of the pump's operation, so we can assure of the safety and the stability of the equipment. The output precision of the equipment, with a good anti-jamming capability, is 1-2% for high flow anesthesia and 1-5% for closed-circuit anesthesia and its self-detecting working is reliable.


Asunto(s)
Anestesia por Circuito Cerrado/instrumentación , Anestésicos por Inhalación/administración & dosificación , Microcomputadores , Diseño de Equipo , Humanos , Diseño de Software
10.
Eur J Pharmacol ; 211(2): 163-7, 1992 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-1319340

RESUMEN

The effect of progesterone on isolated rabbit coronary arteries and its possible mechanism was investigated by measuring changes of isometric tension. Progesterone (1, 3, 10 and 30 microM) induced significant coronary relaxation in K+ (30 mM)-, prostaglandin F2 alpha (3 microM)- or Bay K 8644 (1 microM plus 15 mM K+)- precontracted arteries. There was no difference between endothelium-intact and -denuded coronary arteries from both male and female rabbits, precontracted with these three agents. Haemoglobin, indomethacin, methylene blue, glibenclamide or barium chloride did not affect the relaxation. In endothelium-denuded rabbit coronary arteries, progesterone shifted calcium concentration-dependent constrictor-response curves to the right, the maximal contraction was also reduced. The -log ED50s were 3.6 in control, and 3.3 and 2.9 after incubation with progesterone (3 and 30 microM), respectively. Similar results were obtained in rat aorta. We conclude that progesterone induces significant endothelium-independent relaxation in rabbit coronary arteries in vitro, possibly by affecting calcium influx.


Asunto(s)
Endotelio Vascular/fisiología , Músculo Liso Vascular/efectos de los fármacos , Progesterona/farmacología , Animales , Aorta Torácica/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , GMP Cíclico/fisiología , Endotelio Vascular/efectos de los fármacos , Femenino , Técnicas In Vitro , Masculino , Relajación Muscular/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Conejos , Ratas , Ratas Endogámicas
11.
Br J Pharmacol ; 104(4): 1033-7, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1810590

RESUMEN

1. We assessed the relaxant effect of 17 beta-oestradiol (10(-7), 10(-6) and 10(-5) M) on rabbit isolated coronary arteries precontracted with prostaglandin F2 alpha (3 x 10(-6) M), high extracellular potassium (30 mM) and Bay K 8644 (10(-6) M) plus high extracellular potassium (15 mM) by measuring isometric tension. 17 beta-Oestradiol (10(-6) and 10(-5) M) induced significant relaxation in coronary arteries from male and female rabbits. No differences were seen between arteries with or without endothelium. There were also no differences between coronary arteries isolated from male and female rabbits. 2. Inhibitors of endothelium-derived relaxing factor and vasodilator prostanoids, namely, reduced haemoglobin, N omega-nitro-L-arginine methyl ester and indomethacin, did not affect the relaxation induced by 17 beta-oestradiol in endothelium-intact coronary arteries. 3. Methylene blue, an inhibitor of guanylate cyclase, did not affect the coronary artery relaxation induced by 17 beta-oestradiol. 4. The calcium concentration-dependent contraction curve in potassium-depolarization medium was shifted to the right by 17 beta-oestradiol (10(-6) and 10(-5) M) in the rabbit coronary artery and rat aorta. The -log EC50s of calcium in control and after incubation with 17 beta-oestradiol (10(-6) and 10(-5) M) were 3.7 +/- 0.09, 3.1 +/- 0.10 and 2.8 +/- 0.08 respectively in rabbit coronary arteries and 3.8 +/- 0.11, 3.3 +/- 0.14 and 2.9 +/- 0.15 in rat aorta. 5. The results indicate that 17 beta-oestradiol induces rabbit coronary artery relaxation by an endothelium-independent mechanism in vitro. A calcium antagonistic property may be involved in the mechanism of rabbit coronary arterial relaxation by 17beta-oestradiol.


Asunto(s)
Vasos Coronarios/efectos de los fármacos , Endotelio Vascular/fisiología , Estradiol/farmacología , Músculo Liso Vascular/efectos de los fármacos , Animales , Aorta Torácica/efectos de los fármacos , Arginina/análogos & derivados , Arginina/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Femenino , Hemoglobinas/farmacología , Técnicas In Vitro , Indometacina/farmacología , Masculino , Azul de Metileno/farmacología , Relajación Muscular/efectos de los fármacos , NG-Nitroarginina Metil Éster , Óxido Nítrico/antagonistas & inhibidores , Embarazo , Conejos , Ratas , Ratas Endogámicas
12.
Cardiovasc Res ; 25(11): 930-5, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1813121

RESUMEN

STUDY OBJECTIVE: The purpose was to assess the role of ATP sensitive potassium channels (KATP) in endothelium dependent vasodilatation induced by acetylcholine, or endothelium independent vasodilatation induced by lemakalim in rabbit coronary arteries. DESIGN: The effect of glibenclamide, a specific inhibitor of KATP, on coronary artery relaxation induced by acetylcholine or lemakalim was investigated. The relaxing effectiveness of acetylcholine and lemakalim on coronary arteries precontracted with KCl (K+) or prostaglandin F2 alpha (PGF2 alpha) was compared. EXPERIMENTAL MATERIALS: Left epicardial coronary arteries from male New Zealand white rabbits (2.5-3.0 kg), killed by an overdose of pentobarbitone, were dissected free of connective tissue. Rings suspended in organ baths for the measurement of isometric tension. MEASUREMENTS AND MAIN RESULTS: K+ (30 mmol.litre-1) and PGF2 alpha (3 mumols.litre-1) caused comparable contraction (p greater than 0.05) in endothelium intact or endothelium denuded coronary arterial rings. Acetylcholine induced relaxation was greater in endothelium intact rings precontracted with PGF2 alpha than with K+ and was abolished by the removal of endothelium. Relaxations induced by acetylcholine (0.1 and 0.3 mumol.litre-1) were reduced from 82(SEM 2.7)% and 93(2.8)% to 71(2.4)% and 82(2.7)% (p less than 0.05), and to 63(3.2)% and 79(4.5)% (p less than 0.05 or less than 0.01) by glibenclamide (3 and 10 mumols.litre-1) respectively in PGF2 alpha precontracted rings; and also attenuated (p less than 0.05 or less than 0.01) in K+ precontracted rings. Lemakalim induced relaxation was greater in endothelium denuded rings precontracted with PGF2 alpha than with K+, and was markedly reduced by glibenclamide (p less than 0.01). CONCLUSIONS: These results suggest that activation of KATP may partially be involved in endothelium dependent relaxation induced by acetylcholine in rabbit coronary arteries. Lemakalim-induced endothelium independent relaxation results mainly from activation of KATP.


Asunto(s)
Acetilcolina/farmacología , Adenosina Trifosfato/metabolismo , Benzopiranos/farmacología , Vasos Coronarios/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Pirroles/farmacología , Vasodilatación/efectos de los fármacos , Animales , Cromakalim , Dinoprost/farmacología , Gliburida/farmacología , Técnicas In Vitro , Canales de Potasio/metabolismo , Conejos
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