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1.
Bioorg Chem ; 139: 106727, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37451147

RESUMEN

In this work, a series of 2-(trifluoromethyl)quinolin-4-amine derivatives were designed and synthesized through structural optimization strategy as a microtubule-targeted agents (MTAs) and their cytotoxicity activity against PC3, K562 and HeLa cell lines were evaluated. The half maximal inhibitory concentration (IC50) of 5e, 5f, and 5o suggested that their potency of anti-proliferative activities against HeLa cell lines were better than the combretastatin A-4. Compound 5e showed the higher anti-proliferative activity against PC3, K562 and HeLa in vitro with IC50 values of 0.49 µM, 0.08 µM and 0.01 µM, respectively. Further mechanism study indicated that the representative compound 5e was new class of tubulin inhibitors by EBI competition assay and tubulin polymerization assays, it is similar to colchicine. Immunofluorescence staining revealed that compound 5e apparently disrupted tubulin network in HeLa cells, and compound 5e arrested HeLa cells at the G2/M phase and induced cells apoptosis in a dose-dependent manner. Molecular docking results illustrated that the hydrogen bonds of represented compounds reinforced the interactions in the pocket of colchicine binding site. Preliminary results suggested that 5e deserves further research as a promising tubulin inhibitor for the development of anticancer agents.


Asunto(s)
Antineoplásicos , Tubulina (Proteína) , Humanos , Estructura Molecular , Células HeLa , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismo , Simulación del Acoplamiento Molecular , Polimerizacion , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Antineoplásicos/farmacología , Antineoplásicos/química , Moduladores de Tubulina/farmacología , Moduladores de Tubulina/química , Microtúbulos/metabolismo , Colchicina/metabolismo
2.
Opt Express ; 26(2): 1681-1688, 2018 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-29402039

RESUMEN

A broadband tunable metamaterial graphene absorber is investigated in this paper. The unit cell of the proposed metamaterial graphene absorber is composed of four patch resonators. By tuning the chemical potential of graphene and the geometric size of each patch, the simulated total reflectivity is less than -10 dB from 22.02 to 36.61 THz and with the total thickness of 0.76 um (only 0.09λ at the lowest frequency). The analysis of the surface current, magnetic field and power flow distributions has been performed to better understand the absorption mechanism. Moreover, this proposed absorber achieves its bandwidth tunable characteristics through a voltage biasing of the graphene's Fremi level. This proposed metamaterial graphene absorber (MGA) could be used as smart absorbers, photovoltaic devices and tunable sensors.

3.
Huan Jing Ke Xue ; 44(2): 1029-1039, 2023 Feb 08.
Artículo en Zh | MEDLINE | ID: mdl-36775626

RESUMEN

Phthalic acid esters (PAEs) are ubiquitous environmental pollutants and are recognized as a threat to the environment and agricultural product safety across the world. In order to investigate the level of PAEs in garlic, soils, and agricultural films from Pizhou City, Jiangsu province, China, 11 garlic samples, 106 soil samples, and 4 agricultural film samples were collected and analyzed using GC-MS. In addition, the uptake and transport characteristics of six PAEs compounds classified as priority pollutants by the United States Environmental Protection Agency (EPA) in the garlic cultivar Daqingke were investigated under hydroponic conditions. The results indicated that dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) were the dominant PAEs species in garlic cloves of the different garlic varieties from Pizhou City. The average contents of DBP and DEHP in garlic cloves were 0.611 mg·kg-1 and 0.167 mg·kg-1, respectively, which were significantly higher than those of the commercial varieties of garlic. The concentrations of DBP and DEHP differed in three tissues of garlic bulbs, ordered as the skin of garlic bulb>skin of garlic clove>garlic clove. Dimethyl phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), DBP, and DEHP were the main PAEs species and were detected in all the surface soils collected from Pizhou City. Compared with the soil allowable concentrations of the six PAEs in the United States, the DMP and DBP concentrations in approximately 100% and 63.2% of soil samples exceeded the recommended allowable concentrations set by the EPA. However, the levels of DEP, DIBP, and DEHP in the soils were below the maximum allowable concentrations set by the EPA. Nevertheless, the average content of DEHP in soils was 486 µg·kg-1 and was found to be much higher than that in the other four PAEs. Six PAEs, including DMP, DEP, DIBP, DBP, butyl benzyl phthalate (BBP), and DEHP, were detected in all the agricultural film samples. Among them, the contents of DBP and DEHP in the agricultural films were the highest, accounting for 53.7%-63.2% of the total PAEs. The amount of PAEs present in the residual film was significantly lower than that in the new film, and all six PAEs were detected in garlic or soil samples, suggesting that agricultural film can be an important source of PAEs in garlic farming soils and garlic. Furthermore, the garlic plants absorbed DMP and DEP efficiently from the substrate and showed higher translocation factors (TFs) for DMP and DEP than those for DBP, BBP, DEHP, and di-n-octyl phthalate (DnOP), resulting in a higher accumulation of DMP and DEP in the over-ground parts of garlic. In contrast, DBP and BBP in roots of garlic displayed higher bioconcentration factors (57.4 and 81.5, respectively) compared to those of the other four PAEs, whereas the TFs of DBP and BBP were lower; this may have contributed to the high accumulation of DBP in garlic bulbs. The BCFs and TFs of DEHP and DnOP in garlic were relatively lower, but the DEHP had been detected in all garlic cloves, which may be a result of the higher DEHP contents in soils.


Asunto(s)
Dietilhexil Ftalato , Contaminantes Ambientales , Ajo , Ácidos Ftálicos , Contaminantes del Suelo , Dietilhexil Ftalato/análisis , Contaminantes del Suelo/análisis , Ésteres/análisis , Ácidos Ftálicos/análisis , Dibutil Ftalato , Suelo/química , Contaminantes Ambientales/análisis , China
4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(1): 1-6, 2019 Feb.
Artículo en Zh | MEDLINE | ID: mdl-30738439

RESUMEN

OBJECTIVE: To explore the possible molecular mechanism of Ikaros regulation on FUT4 expression by analyzing the correlation of the functional state of Ikaros with level of FUT4 expression, so as to provide the theoretical basis for personalized treatment in children with ALL. METHODS: The subtypes of Ikaros were identified by nested PCR and sequencing. The expression level of FUT4 was detected by quantitative PCR and analyzed by ΔΔCt method in the early stage of treatment, remission and relapse of ALL. RESULTS: Ik1 and Ik2 were the main functional subtypes, and the dominant negative Ikaros was Ik6; the Ik6 was detected in 23 patients with ALL. It was found that 2.73% patients expressing Ik6 alone and 18.18% patients with heterozygous expression were detected. The expression of FUT4 in the newly diagnosed ALL was higher than that in the control group, and the functional Ikaros negatively correlated with the FUT4 expression(r=-0.6329). CONCLUSION: Dominant negative Ikaros closely correlated with the relapse of acute lymphoblastic leukemia in children. The functional Ikaros negatively correlated with FUT4 expression. Ikaros inhibit the transcriptional activity of FUT4, that may be the molecular mechanism of Ikaros regulating the expression of FUT4.


Asunto(s)
Fucosiltransferasas/metabolismo , Factor de Transcripción Ikaros/metabolismo , Antígeno Lewis X/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras , Enfermedad Aguda , Niño , Humanos , Isoformas de Proteínas , Recurrencia
5.
Comput Methods Programs Biomed ; 84(2-3): 162-73, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16962203

RESUMEN

This paper presents a strategy for segmenting urinary sediment based on wavelet, morphology and combination method. Firstly, the wavelet transforms and morphology are used to get rid of the effect of the defocusing and get the subimages that include the particles. Then based on the characteristics of the subimages, edge detection and adaptive thresholding are employed adaptively. Finally, a simplified watershed algorithm for the overlapping particles is used. The experiment results show that the method can segment the defocusing urinary sediment images effectively and precisely.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Urinálisis , Orina , Humanos
6.
Zhongguo Yi Liao Qi Xie Za Zhi ; 30(3): 184-7, 223, 2006 May.
Artículo en Zh | MEDLINE | ID: mdl-16929775

RESUMEN

The portable gastrointestinal wireless endoscope image receiver is developed and based on TMS320C6211 DSP. It can receive and demodulate the modulated signal which is transmitted from the camera-capsule, and then output the video signal. The synchronizing signals offered by SAA7114H are made best of and are used to design the time logic circuit. The fitful video signal can be collected under the control of the time logic circuit. The circuit can automatically get rid of useless blank data and only collect effective and good-quality video signals, and storage them in CF card. In addition, the image signal can be processed and compressed by DSP, and thus the data storage space and the data- analyzing time can be saved.


Asunto(s)
Endoscopía Capsular/métodos , Endoscopios Gastrointestinales , Interpretación de Imagen Asistida por Computador/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Endoscopios en Cápsulas , Sistemas de Computación , Diseño de Equipo , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Programas Informáticos
7.
Ying Yong Sheng Tai Xue Bao ; 24(1): 49-56, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23717989

RESUMEN

In this study, measurements were made on the leaf water potential (psi1), stomatal conductance (g(s)), transpiration rate, leaf area index, and sapwood area of mature Acacia mangium, aimed to understand the relationships of the leaf hydraulic conductance (K1) with the leaf water use and photosynthetic characteristics of the A. mangium in wet season (May) and dry season (November). The ratio of sapwood area to leaf area (A(sp)/A(cl)) of the larger trees with an average height of 20 m and a diameter at breast height (DBH) of 0.26 m was 8.5% higher than that of the smaller trees with an average height of 14.5 m and a DBH of 0.19 m, suggesting that the larger trees had a higher water flux in their leaf xylem, which facilitated the water use of canopy leaf. The analysis on the vulnerability curve of the xylem showed that when the K1 decreased by 50%, the psi1 in wet season and dry season was -1.41 and -1.55 MPa, respectively, and the vulnerability of the xylem cavitation was higher in dry season than in wet season. The K1 peak value in wet season and dry season was 5.5 and 4.5 mmol x m(-2) x s(-1) x MPa(-1), and the maximum transpiration rate (T(r max)) was 3.6 and 1.8 mmol x m(-2) x s(-1), respectively. Both the K1 and T(r max), were obviously higher in wet season than in dry season. Within a day, the K1 and T(r), fluctuated many times, reflecting the reciprocated cycle of the xylem cavitation and refilling. The leaf stomatal closure occurred when the K1 declined over 50% or the psi1 reached -1.6 MPa. The g(s) would be maintained at a high level till the K1 declined over 50%. The correlation between the hydraulic conductance and photosynthetic rate was more significant in dry season than in wet season. The loss of leaf hydraulic conductance induced by seasonal change could be the causes of the decrease of T(r) and CO2 gas exchange.


Asunto(s)
Acacia/fisiología , Fotosíntesis/fisiología , Hojas de la Planta/metabolismo , Transpiración de Plantas/fisiología , Estaciones del Año , Agua/metabolismo , Acacia/metabolismo , China , Ecosistema
8.
Ying Yong Sheng Tai Xue Bao ; 23(4): 979-84, 2012 Apr.
Artículo en Zh | MEDLINE | ID: mdl-22803463

RESUMEN

Based on the validation of Granier's empirical formula for calculating tree stem sap flux density, a comparative study was conducted on the measurement of Bambusa chungi sap flow by using different lengths of thermal dissipation probe (TDP), aimed to approach the applicability of TDP in measuring the sap flow of B. chungii. The difference in the daily change of the sap flow between B. chungii and nearby growing Schima superb was also analyzed. Because of the thinner bamboo wall and the heterogeneous anatomy, the sap flux density of B. chungii measured by 10 mm long probe could be underestimated, but that measured by 8 and 5 mm long probes could be relatively accurate. The comparison of the sap flow between B. chungii and nearby growing S. superba revealed that both the mean sap flux density and its daily change pattern' s skewness of B. chungii were higher than those of S. superba, but the nighttime sap flow of B. chungii was less than that of S. superba, indicating that the water recharge of B. chungii during nighttime was less active than that of S. superba. It was suggested that using TDP to investigate the sap flow of bamboo would be feasible, but careful calibration would be required before the TDP was put into application on different bamboo species.


Asunto(s)
Bambusa/fisiología , Técnicas de Química Analítica/instrumentación , Transpiración de Plantas/fisiología , Agua/metabolismo , Bambusa/metabolismo , Tallos de la Planta/metabolismo , Tallos de la Planta/fisiología
9.
Ying Yong Sheng Tai Xue Bao ; 23(7): 1751-7, 2012 Jul.
Artículo en Zh | MEDLINE | ID: mdl-23173445

RESUMEN

To understand the nighttime water recharge of tree through its sap flow is beneficial to the precise estimation of total transpiration and canopy stomatal conductance, and to the further understanding of the time lag between canopy transpiration and stem sap flow. By using Granier's thermal dissipation probe, this paper measured the stem sap flow of Schima superba, and synchronously measured the main environmental factors including air temperature, relative humidity, photosynthetically active radiation, and soil moisture content, and also analyzed the water recharge through nighttime stem flow of S. superba at daily and seasonal scales. The sap flow density of S. superba was lower at night than at daytime, and the nighttime sap flow density had a larger variation in dry season than in wet season. The water recharge at night generally started from sunset when radiation was approaching zero, and lasted up to midnight (18:00-22:00). No significant difference was observed in the nighttime water recharge among seasons, and no significant correlations were found between the nighttime water recharge and environmental factors, but the nighttime water recharge was well regressed with the diameter at breast height, tree height, tree canopy size, stem biomass, and canopy biomass, suggesting that tree form features and biomass could better explain the nighttime water recharge. The contribution of nighttime water recharge to the total transpiration varied significantly with seasons, and was obviously higher in dry season than in wet season.


Asunto(s)
Ecosistema , Tallos de la Planta/fisiología , Transpiración de Plantas/fisiología , Theaceae/fisiología , Agua/fisiología , Técnicas de Química Analítica/instrumentación , China , Estaciones del Año
10.
Ying Yong Sheng Tai Xue Bao ; 21(10): 2457-64, 2010 Oct.
Artículo en Zh | MEDLINE | ID: mdl-21328929

RESUMEN

The eigenvalues of continuous sap flow pattern, i. e. , skewness and kurtosis, were used to investigate the water usage of Schima superba with different diameter at breast height (DBH), and the method of normalization was firstly applied to eliminate the effects of strong affecting factor (photosynthetic active radiation, PAR) to explore the possible relationship between weak affecting factor (soil moisture) and sap flow. Generally, the trees with larger DBH had smaller skewness of sap flux density and later-appeared but larger peak values, suggesting that much more water was transpired, and the larger trees showed smaller skewness and later-appeared larger peak values in wet season than in dry season, suggesting that more water was transpired in wet season. On the other hand, smaller trees had lesser differences in the skewness between dry and wet seasons, suggesting that there was no significant difference in the transpiration between the two seasons. The relationship between individual tree's transpiration and soil moisture was significant and positive after the two parameters being normalized with PAR peak values. When the soil moisture content was higher, the transpiration of the trees with larger DBH was steadily increasing with soil moisture, while that of the trees with moderate or smaller DBH had opposite trend, presumably due to their transpiration and water absorption were approached to the limit.


Asunto(s)
Tallos de la Planta/anatomía & histología , Transpiración de Plantas , Suelo/análisis , Theaceae/metabolismo , Agua/análisis , Matemática , Theaceae/anatomía & histología
11.
Ying Yong Sheng Tai Xue Bao ; 20(3): 485-92, 2009 Mar.
Artículo en Zh | MEDLINE | ID: mdl-19637580

RESUMEN

Different parts of twenty dominant plant species in five plantation communities on the subtropical hilly lands in Heshan of Gunagdong as well as the litters from three of the five plantation communities were sampled, and their gross caloric value (GCV) and ash content were measured by using a PARR-1281 oxygen bomb calorimeter and a muffle furnace. Based on the measurements, the ash-free caloric value (AFCV) of the samples was calculated, and the characteristics of caloric value and ash content of the samples, according to plant part, individual, and plant growth form, were analyzed. The results showed that the GCV and AFCV of leaf, branch, stem wood, stem bark, and root were in the range of 10.7-22.17 kJ x g(-1) and 13.89-23.04 kJ x g(-1), respectively. The GCV and AFCV of leaf were significantly higher than those of other parts (P < 0.05), and the individual plant' s weighted mean values of GCV and AFCV were in the range of 14.24-19.43 and 16.63-20.99 kJ x g(-1), respectively. The mean AFCV of plantation communities was in the order of tree layer (19.55 kJ x g(-1)) > shrub layer (19.46 kJ x g(-1) > herb layer (18.77 kJ x g(-1)), with indigenous coniferous tree (19.86 kJ x g(-1)) > indigenous broad-leaved tree (19.55 kJ x g(-1)) > exotic eucalyptus (19.18 kJ x g(-1)), while the mean ash content was just the opposite. In Acacia mangium, coniferous, and Schima plantation communities, the GCV and AFCV of litters were higher than those of various plant parts (P < 0.01). The litter-falls in A. mangium and coniferous plantations had higher mean GCV and AFCV than the litters and fresh leaves of tree layer, while the fresh leaves of tree layer in Schima plantation showed higher mean GCV and AFCV.


Asunto(s)
Ecosistema , Metabolismo Energético , Árboles/metabolismo , China , Árboles/química
12.
Ying Yong Sheng Tai Xue Bao ; 20(11): 2594-602, 2009 Nov.
Artículo en Zh | MEDLINE | ID: mdl-20135988

RESUMEN

By using stable carbon isotope technique, the leaf-level 13C discrimination was integrated to canopy-scale photosynthetic discrimination (Deltacanopy) through weighted the net CO2 assimilation (Anet) of sunlit and shaded leaves and the stand leaf area index (L) in an A. mangium plantation, and the carbon isotope fluxes from photosynthesis and respiration as well as their net exchange flux were obtained. There was an obvious diurnal variation in Deltacanopy, being lower at dawn and at noon time (18.47 per thousand and 19.87 per thousand, respectively) and the highest (21.21 per thousand) at dusk. From the end of November to next May, the Deltacanopy had an increasing trend, with an annual average of (20.37 +/- 0.29) per thousand. The carbon isotope ratios of CO2 from autotrophic respiration (excluding daytime foliar respiration) and heterotrophic respiration were respectively (- 28.70 +/- 0.75) per thousand and (- 26.75 +/- 1.3) per thousand in average. The delta13 C of nighttime ecosystem-respired CO2 in May was the lowest (-30.14 per thousand), while that in November was the highest (-28.01 per thousand). The carbon isotope flux of CO2 between A. mangium forest and atmosphere showed a midday peak of 178.5 and 217 micromol x m(-2) x s(-1) x per thousand in May and July, with the daily average of 638.4 and 873.2 micromol x m(-2) x s(-1) x per thousand, respectively. The carbon isotope flux of CO2 absorbed by canopy leaves was 1.6-2.5 times higher than that of CO2 emitted from respiration, suggesting that a large sum of CO2 was absorbed by A. mangium, which decreased the atmospheric CO2 concentration and improved the environment.


Asunto(s)
Acacia/crecimiento & desarrollo , Acacia/metabolismo , Dióxido de Carbono/metabolismo , Ecosistema , Fotosíntesis/fisiología , Dióxido de Carbono/análisis , Isótopos de Carbono/química , Hojas de la Planta/fisiología , Transpiración de Plantas/fisiología , Estaciones del Año
13.
Ying Yong Sheng Tai Xue Bao ; 20(1): 13-9, 2009 Jan.
Artículo en Zh | MEDLINE | ID: mdl-19449559

RESUMEN

By using Granier's thermal dissipation probe, the sap flow of 14 sample trees in a 22-year old Acacia mangium forest in hilly land of South China was continuously measured in 2004. Environmental factors including the photosynthetically active radiation, air temperature, and air humidity above canopy and the water content in 0-30 cm soil layer were monitored simultaneously. Combining with the tree morphological features and sap flux density, the whole-tree transpiration, canopy stomatal conductance, and ratio of leaf area to sapwood area were calculated by simplified Whitehead and Jarvis equation, and the effects of tree height on these three parameters were analyzed. The results indicated that under sufficient soil water supply, the whole-tree transpiration increased in a quadratic polynomial way with tree height (P < 0.01), and the diurnal variation of canopy stomatal conductance was of one-peak pattern. Within the measured range of photosynthetically active radiation, taller A. mangium trees had higher reference canopy stomatal conductance and higher sensitivity of canopy stomatal conductance to vapor pressure deficit, compared with the shorter ones. The ratio of leaf area to sapwood area was (1.837 +/- 0.048) m2 x cm(-2), and increased in power function with tree height. A. mangium had no obvious hydraulic limitation and


Asunto(s)
Acacia/metabolismo , Acacia/fisiología , Tallos de la Planta/fisiología , Transpiración de Plantas/fisiología , Agua/metabolismo , Ecosistema
14.
Ying Yong Sheng Tai Xue Bao ; 19(2): 225-30, 2008 Feb.
Artículo en Zh | MEDLINE | ID: mdl-18464623

RESUMEN

Based on the measurement of the stem sap flow of Acacia mangium with Granier' s thermal dissipation probe, and the cross-correlation and time serial analysis of the sap flow and corresponding photosynthetically active radiation and vapor pressure deficit, this paper studied the time lag effect between the stem sap flow of A. mangium and the driving factors of the tree canopy transpiration. The results indicated that the main driving factors of the transpiration were photosynthetically active radiation (PAR) and vapor pressure deficit (VPD). Sap flux density (Js) was more dependent on PAR than on VPD, and the dependence was more significant in dry season than in wet season. Sap flow lagged behind PAR but advanced than VPD in both dry and wet seasons. The time lag did not show any significant variation across different size tree individuals, but showed significant variation in different seasons. Time lag effect was not correlated with tree height, diameter at the breast, and canopy size. The time lag between Js and VPD was significantly related to nighttime water recharge in dry season, but reversed in wet season.


Asunto(s)
Acacia/fisiología , Fotosíntesis/fisiología , Tallos de la Planta/fisiología , Agua/metabolismo , Acacia/crecimiento & desarrollo , Transpiración de Plantas/fisiología , Estaciones del Año , Factores de Tiempo
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