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1.
Inflammopharmacology ; 31(4): 1715-1729, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37261627

RESUMEN

Cardiovascular diseases (CVDs) are a leading cause of global mortality and have a high incidence rate worldwide. The function of inflammasomes in CVDs has received a lot of attention recently, and the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome may be a new target for the prevention and treatment of CVDs. Flavonoids, which are found in food and plant extracts, inhibited inflammation in CVDs by regulating the NLRP3 inflammasome. CB-Dock was used to investigate whether 34 flavonoids from natural products acted on NLRP3 inflammasome. In brief, the PDB format of NLRP3 was selected as a protein file, and 34 flavonoids in SDF format were selected as the ligand file, and then input to CB-Dock for molecular docking. The docking results showed that epigallocatechin-3-gallate (EGCG), amentoflavone, baicalin, scutellarin, vitexin, silibinin, and puerarin had good binding affinities to NLRP3, which could be used as NLRP3 inhibitors, and aid in the discovery of lead compounds for the design and development of CVDs.


Asunto(s)
Enfermedades Cardiovasculares , Inflamasomas , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedades Cardiovasculares/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Flavonoides/farmacología
2.
Ying Yong Sheng Tai Xue Bao ; 32(8): 2886-2894, 2021 Aug.
Artículo en Chino | MEDLINE | ID: mdl-34664462

RESUMEN

Rainfall intensity, slope length, and slope gradient are the important factors affecting runoff and sediment yield. In order to quantitatively analyze the effects of rainfall intensity, slope length, and slope gradient on the erosion process of Ansai loess slope in loess hilly and gully region, we analyzed the variation of runoff and sediment yield on Ansai loess with two slope lengths (5, 10 m), three slopes (5°, 10°, 15°) and two rainfall intensities (60, 90 mm·h-1) in an indoor simulated rainfall experiment. The results showed that the initial runoff generation time decreased with the increases of slope length, though the overall change was not significant. The initial runoff generation time decreased with the increases of rainfall intensity. Compared with the intensity of 60 mm·h-1, the initial runoff generation time decreased by 5.7-18 min under the intensity of 90 mm·h-1. Among them, the runoff initiation time on the slope of 10° was the fastest. With the duration of rainfall, runoff yield rate increased rapidly at first, and then gradually fluctuated around a certain value. The sediment yield rate increased rapidly in a short period of time at the initial stage of runoff generation, and then decreased after reaching the maximum, and being gradua-lly stable. The rates of runoff and sediment yield increased with the increases of slope length and rainfall intensity, but the law of change with slope was not obvious. With the increases of rainfall intensity, slope length and gradient, the total sediment yield increased accordingly. Under the rainfall intensity of 90 mm·h-1, the slope surface with the length of 10 m and slope of 15° generated rill, leading to the highest total erosion amount (11885.66 g). Under the rainfall intensity of 60 mm·h-1, the erosion amount per unit area decreased with the increases of slope length, and there was a critical erosion slope length in 5-10 m slope section. Slope length, slope and rainfall intensity all played a promoting role in runoff process. Rainfall intensity, slope length, and their interaction contributed more to runoff yield rate and total erosion amount. Rainfall intensity contributed the most to runoff yield rate, with a contribution rate of 49.8%. The contribution rate of slope length to the total erosion was the largest, which reached 37.8%.


Asunto(s)
Lluvia , Movimientos del Agua , China , Sedimentos Geológicos , Suelo
3.
Materials (Basel) ; 13(18)2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32967241

RESUMEN

A new green and sustainable extraction technique, namely osmosis extraction (OE), was developed for efficient extracting flavonoids from Folium nelumbinis by changing the osmotic pressure. The antioxidant activities of the extracted flavonoids were also evaluated. Ethanol and ammonium sulfate were selected for the OE system because they are environmentally friendly. The maximum flavonoids concentration in the top phase was obtained with an ethanol volume fraction of 42.0% and the salt mass of 1.9 g. The kinetic behavior of the extraction process showed that OE had higher efficiencies especially coupled with ultrasonication due to the accompanying and serious morphological changes of Folium nelumbinis cells observed by digital microscope and nano-computed tomography (nano-CT). Results of morphological and anatomical features showed that the higher intracellular chemical potential made the cell expand and even led to bursting. The results also showed that the extraction efficiency of flavonoids with high antioxidant activities was higher than that of the traditional method. The interface effect enhanced the extraction during the salting-out extraction and osmosis was the main factor that improved the extraction efficiency.

4.
Ying Yong Sheng Tai Xue Bao ; 31(2): 590-598, 2020 Feb.
Artículo en Chino | MEDLINE | ID: mdl-32476353

RESUMEN

The variations of runoff and sediment flux are important factors influencing the socioeconomic development of Thailand. Based on the dataset of runoff and sediment flux during 1980-2014 at the Ubon hydrological station in the lower Mun River, a tributary of the Mekong River, the temporal variations of runoff and sediment flux were analyzed with the linear regression method, Mann-Kendall test, and wavelet transform method. The driving forces for the variations of runoff and sediment flux were discussed. The results showed that annual runoff in the Mun River basin increased slightly, while the sediment flux presented a decreasing trend. The changes of sediment flux and runoff were consistent before 2000. However, the sediment flux significantly decreased after 2000. During the study period, both the runoff and sediment flux during the flood seasons showed decrease trend. The abrupt change points of runoff and sediment flux did not occur in the same year, which were in 1999, 2006 and 2011 for runoff and in 1986, 1999 and 2011 for sediment, respectively. The main cycles of runoff amount were 14, 8 and 4 years, respectively, while those of sediment flux were 32, 12, 9 and 4 years, respectively. Except for the 32-year cycle of sediment flux, the main cycles of runoff and sediment flux were almost similar and both were mainly related to the Southern Oscillation, polar movement, sunspot activity, and other factors. There was a significant correlation between monthly runoff and sediment flux. Sea-air interaction and human activity were important factors influencing runoff and sediment flux in the Mun River basin. El Nino and La Nina were closely related to rainfall which in turn affected the runoff and sediment flux in the basin. Since 2000, the construction area increased and the forest area decreased, which increased the runoff in the basin, while the reservoirs and other engineering measures reduced the runoff and sediment flux, and thus offset the impact of decreased forest lands on sediment flux.


Asunto(s)
Monitoreo del Ambiente , Ríos , Actividades Humanas , Humanos , Hidrología , Tailandia
5.
Am J Physiol Endocrinol Metab ; 318(5): E723-E735, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31910027

RESUMEN

Gestational diabetes mellitus (GDM) is a metabolic disorder characterized by insulin resistance, and patients with GDM have a higher risk of cardiovascular disease. Multiple microRNAs (miRNAs) are reported to be involved in the regulation of myocardial injury. Moreover, miR-873 was predicted to target insulin-like growth factor binding protein 2 (IGFBP2) through bioinformatic analysis, which was further confirmed using a luciferase assay. Thus, our objective was to assess whether microRNA-873 (miR-873) affects insulin resistance and myocardial injury in an established GDM rat model. The GDM rats were treated with miR-875 mimic or inhibitor or IGFBP2 siRNA. The effects of miR-875 and IGFBP2 on the cardiac function, insulin resistance, and myocardial injury were evaluated by hemodynamic measurements, determination of biochemical indices of myocardium and serum, and insulin homeostatic model assessment. The results indicated that downregulation of miR-873 upregulated the expression of IGFBP2 and promoted the activation of phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) axis. With downregulation of miR-873 in GDM rats, the cardiac function was improved and the myocardial apoptosis was inhibited, coupled with elevated activity of superoxide dismutase, carbon monoxide synthase, and the nitric oxide content. In addition, the inhibition of miR-873 in GDM rats modulated the insulin resistance and reduced myocardial apoptosis. Overall, the data showed that inhibition of miR-873 by targeting IGFBP2 may regulate the insulin resistance and curtail myocardial injury in GDM rats through activating the PI3K/AKT/mTOR axis, thus providing a potential means of impeding the progression of GDM.


Asunto(s)
Diabetes Gestacional/metabolismo , Regulación de la Expresión Génica , Resistencia a la Insulina/fisiología , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocardio/metabolismo , Animales , Apoptosis/fisiología , Diabetes Gestacional/genética , Regulación hacia Abajo , Femenino , Hemodinámica , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , MicroARNs/genética , Daño por Reperfusión Miocárdica/genética , Embarazo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba
6.
Zhongguo Zhong Yao Za Zhi ; 40(7): 1388-91, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26281566

RESUMEN

OBJECTIVE: The study aimed to test if Paridis Rhizoma total saponins (PRTS) could induce apoptosis of human gastric cancer cell MKN-45. METHOD: Based on the previous researches, PRTS was set by different concentrations to treat human gastric cancer cell for 12 h (5, 10, 20 mg x L(-1)). Fluorescent staining methods were adopted to observe apoptotic morphological changes of MKN-45. The apoptosis rates were analyzed by flow cytometry with Annexin V-FITC/PI staining. The enzymatic activities of caspase-3 and caspase-8 were measured by ELISA. The protein levels of Fas and FasL were detected by Western blotting. RESULT: Under a fluorescence microscope, MKN-45 treated by PRTS was seen typical apoptotic morphological features. PRTS significantly increased the rate of apoptosis. Compared with the control group, there exsited significant differences in apoptosis rate of PRTS concentration of 20 mg x L(-1) (P < 0.01); besides, the enzymatic activities of caspase-3 and caspase-8 were promoted obviously after the effect of PRTS on MKN-45 cells for 12 h (P < 0.01). The protein levels of Fas and FasL in the MKN-45 were upgraded significantly. CONCLUSION: PRTS can induce apoptosis of human gastric cancer cell MKN-45 , which is concerned with caspase-3 and caspase-8 and upgraded Fas and FasL.


Asunto(s)
Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Proteína Ligando Fas/metabolismo , Magnoliopsida/química , Saponinas/farmacología , Neoplasias Gástricas/metabolismo , Receptor fas/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 8/genética , Caspasa 8/metabolismo , Línea Celular Tumoral , Humanos , Rizoma/química , Transducción de Señal/efectos de los fármacos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/fisiopatología
7.
Melanoma Res ; 24(6): 545-55, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25244079

RESUMEN

The TLR4/NF-κB signaling pathway plays a critical role in tumor progression. Andrographolide (Andro) has been reported to have anticancer activity in multiple types of cancer. However, the pharmacological activities of Andro in melanoma are not completely understood. In this study, we defined the anticancer effects of Andro in melanoma and elucidated its potential mechanisms of action. Our experiments showed that Andro significantly inhibited melanoma tumor growth and metastasis by inducing cell cycle arrest and apoptosis. In addition, Andro significantly inhibited the TLR4/NF-κB signaling pathway. Furthermore, the inactivation of TLR4/NF-κB signaling inhibited the mRNA and protein expression of CXCR4 and Bcl-6, which are antitumor genes. This work provides evidence that the TLR4/NF-κB signaling pathway is a potential therapeutic target and may also be indispensable in the Andro-mediated anticancer effect in melanoma.


Asunto(s)
Antiinflamatorios/farmacología , Proliferación Celular/efectos de los fármacos , Diterpenos/farmacología , Melanoma Experimental/patología , Neoplasias Cutáneas/patología , Animales , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Femenino , Neoplasias Pulmonares/prevención & control , Neoplasias Pulmonares/secundario , Melanoma Experimental/metabolismo , Ratones , Ratones Endogámicos C57BL , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/metabolismo , Receptor Toll-Like 4/antagonistas & inhibidores , Receptor Toll-Like 4/metabolismo , Carga Tumoral/efectos de los fármacos
8.
Ying Yong Sheng Tai Xue Bao ; 24(7): 1856-62, 2013 Jul.
Artículo en Chino | MEDLINE | ID: mdl-24175514

RESUMEN

Soil cores were collected from a 28.5 hm2 slope farmland in the black soil region of Northeast China. Based on the sampled data of 137Cs, 210Pb(ex) and SOC, the potentials of applying 137Cs and 210Pb(ex) for assessing SOC redistribution were evaluated, aimed to approach the impact of soil erosion on soil organic carbon (SOC) in black soil region. At both planar and vertical directions, the 137Cs, 210Pb(ex) and SOC in the farmland had similar distribution patterns. Although there were large planar variations in the 137Cs and 210Pb(ex) areal activities and the SOC stock as affected by soil erosion and deposition, the 137Cs, 210Pb(ex) and SOC had similar changing trends over the landscape. Two depth distribution profiles were also used to study the relations of 137Cs and 210Pb(ex) with SOC. At eroded site, the radioactivities of 137Cs and 210Pb(ex) and the SOC mass fraction did not show large variations in 0-25 cm soil layer, but decreased sharply below 25 cm. For the deposition sample, the radioactivities of 137Cs and 210Pb(ex) in 0-100 cm soil increased firstly and then decreased. The SOC mass fraction also had similar depth distribution pattern in this soil layer. The 137Cs and 210Pb(ex) presented positive linear correlations with the SOC, indicating that 137Cs, 210Pb(ex) and SOC moved with the same physical mechanism in the farmland, and fallout 137Cs and 210Pb(ex) could be used to study spatio-temporal distribution characteristics of SOC in the black soil region under the condition of soil erosion.


Asunto(s)
Carbono/análisis , Radioisótopos de Cesio/análisis , Monitoreo del Ambiente/métodos , Radioisótopos de Plomo/análisis , Suelo/química , China , Ecosistema , Compuestos Orgánicos/análisis , Trazadores Radiactivos , Contaminantes Radiactivos del Suelo/análisis , Análisis Espacio-Temporal
9.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(4): 394-8, 2013 Aug.
Artículo en Chino | MEDLINE | ID: mdl-23926002

RESUMEN

OBJECTIVE: To clone an A3IP gene and investigate its cellular and histological localization based on previous research which has identified part of A3IP sequence interacting with carboxyl-terminal of ataxin-3. METHODS: Bioinformatic and Northern blotting were applied to clone the A3IP gene and detect the expression of its transcripts in various human tissues and brain regions. Western blotting and immunofluorescence staining were applied to detect expression of A3IP protein in cultured cells. Immunohistochemistry staining was applied to study the expression of A3IP protein in various human tissues and brain regions. RESULTS: cDNA cloning of A3IP gene's reading frame and its sequence assembly were completed. Three transcripts (1 kb, 1.35 kb and 6 kb, respectively) of A3IP were found to express in various human tissues and brain regions. A3IP pEGFP expresses in cytoplasm of cultured COS-7 cells and various human tissues and brain regions including cerebral cortex, cerebellum, muscle, peripheral nerve, liver and kidney. CONCLUSION: The cloned A3IP gene encodes A3IP, a novel ataxin-3 interacting protein. Three transcripts of A3IP are expressed in various human tissues and brain regions. A3IP is a cytosolic protein.


Asunto(s)
Proteínas Portadoras/metabolismo , Clonación Molecular , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Ataxina-3 , Secuencia de Bases , Proteínas Portadoras/genética , Humanos , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Unión Proteica , Transporte de Proteínas , Proteínas Represoras/genética
10.
J Zhejiang Univ Sci B ; 12(3): 193-200, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21370504

RESUMEN

Central composite design (CCD), together with multiple linear regression, was successfully used to optimize the electrophoretic buffer system of micellar electrokinetic capillary chromatography (MEKC) for the determination of albiflorin, paeoniflorin, liquiritin, and glycyrrhizic acid in the traditional Chinese medicine (TCM) prescription, Yangwei granule. Concentrations of sodium deoxycholate (SDC) and borate, and proportions of ammonia, acetonitrile, and methanol were optimized. The total resolutions of peaks between the analytes and their adjacent peaks in real samples were integrated into the evaluation index of separation efficiency. The optimum electrophoretic buffer contained 80 mmol/L SDC, 20 mmol/L borate, 5% (v/v) methanol, 0.5% (v/v) ammonia, and 5% (v/v) acetonitrile. The correlation coefficients (R(2)) between the peak areas and the corresponding concentrations of analytes were greater than 0.9956. The limits of detection (LODs) (S/N=3) of the analytes were 0.97-4.00 µg/ml. The results indicate the superiority of CCD in optimizing the separation conditions of complex samples such as TCM prescriptions.


Asunto(s)
Química Farmacéutica/métodos , Cromatografía Capilar Electrocinética Micelar/métodos , Medicamentos Herbarios Chinos/síntesis química , Acetonitrilos/análisis , Amoníaco/análisis , Benzoatos/análisis , Boratos/química , Hidrocarburos Aromáticos con Puentes/análisis , Tampones (Química) , Ácido Desoxicólico/análisis , Medicamentos Herbarios Chinos/química , Flavanonas/análisis , Glucósidos/análisis , Ácido Glicirrínico/análisis , Metanol/análisis , Metanol/química , Micelas , Monoterpenos , Reproducibilidad de los Resultados
11.
Pharmacology ; 83(5): 294-300, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19365154

RESUMEN

Effects of the cholinesterase inhibitors tacrine and bis(7)- tacrine (0.25-20 micromol/kg, s.c.) on locomotor activity and passive-avoidance response were investigated in mice treated with scopolamine (SCP, 1 or 5 micromol/kg, i.p.), using an open-field test and step-through task with a 24-hour retention interval. Drugs were given 30 min prior to the first session. During the acquisition session, SCP treatment increased the locomotor activity (10-16%). Tacrine, but not bis(7)-tacrine, cotreatment significantly reduced the locomotor activity by 23 or 27%, when compared with the SCP-treated control mice. In the step-through task, tacrine or bis(7)-tacrine coadministration dose-dependently attenuated the increase in the number of footshocks (by 50 or 58%) in SCP-treated mice. The lowest dose of tacrine and bis(7)-tacrine for prolonging the retention latency (up to 500%) in SCP-treated mice was 5 and 1 micromol/kg, respectively. Tacrine and bis(7)-tacrine inhibited brain acetylcholinesterase (AChE) activity 15 min (but not 30 min) after the drug administration in mice. At the same dose of 20 micromol/kg, the bis(7)-tacrine-induced AChE inhibition in serum was 14-fold higher than that of tacrine. The results indicated that bis(7)-tacrine was less potent than tacrine in causing motor dysfunction. However, bis(7)-tacrine was more potent than tacrine in the cognitive enhancement of SCP-induced memory loss and in AChE inhibition.


Asunto(s)
Acetilcolinesterasa/sangre , Acetilcolinesterasa/metabolismo , Reacción de Prevención/efectos de los fármacos , Inhibidores de la Colinesterasa/farmacología , Escopolamina/farmacología , Tacrina/análogos & derivados , Tacrina/farmacología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Inhibidores de la Colinesterasa/administración & dosificación , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Masculino , Ratones , Ratones Endogámicos ICR , Actividad Motora/efectos de los fármacos , Escopolamina/administración & dosificación , Tacrina/administración & dosificación
12.
J Pharm Pharmacol ; 60(3): 399-403, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18284822

RESUMEN

The effects of schisandrin B (Sch B) on liver and serum lipid contents were investigated in mice with experimentally-induced hypercholesterolaemia. Hypercholesterolaemia was induced either by oral administration of a cholesterol/bile salts mixture (2/0.5 g kg(-1)) for four days or by feeding a high fat/cholesterol/bile salts (10/1/0.3%, w/w) diet for seven days. Daily co-administration of Sch B (50-200 mg kg(-1), i.g.) for four or six days, respectively, decreased hepatic total cholesterol (TC) and triglyceride (TG) levels (by up to 50% and 52%, respectively) in hypercholesterolaemic mice. Sch B treatment also increased hepatic indices (14-84%) in hypercholesterolaemic mice. The results indicated that Sch B treatment could decrease hepatic TC and TG levels, and increase liver weight, in mouse models of hypercholesterolaemia. Fenofibrate treatment (100 mg kg(-1)) produced effects similar to those of Sch B on the hepatic index and lipid levels of hypercholesterolaemic mice.


Asunto(s)
Hígado Graso/tratamiento farmacológico , Hipercolesterolemia/tratamiento farmacológico , Hipolipemiantes/farmacología , Lignanos/farmacología , Compuestos Policíclicos/farmacología , Schisandra/química , Animales , Ácidos y Sales Biliares/toxicidad , Colesterol/metabolismo , Colesterol en la Dieta/toxicidad , Ciclooctanos/administración & dosificación , Ciclooctanos/aislamiento & purificación , Ciclooctanos/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Hígado Graso/etiología , Hígado Graso/patología , Fenofibrato/farmacología , Hipercolesterolemia/complicaciones , Hipolipemiantes/aislamiento & purificación , Lignanos/administración & dosificación , Lignanos/aislamiento & purificación , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Ratones Endogámicos ICR , Compuestos Policíclicos/administración & dosificación , Compuestos Policíclicos/aislamiento & purificación , Triglicéridos/metabolismo
13.
J Environ Sci (China) ; 19(4): 482-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17918649

RESUMEN

This study addresses the adaptation of Nitraria sphaerocarpa to blown sand at the edge of a desert oasis with regard to the aspects of soil seed banks, seedlings, and population. Horizontally, the total number of seeds per unit area decreased from the shrub canopy center to intershrub areas, and most seeds were found under shrub canopies. Vertically, the highest proportion of seeds was found at depths of 5-10 cm. The emergence percentage, seedling mass, and seedling height, which were significantly affected by both burial depth and seed size, were highest at the optimal burial depth of 2 cm, and decreased with increasing burial depth in each seed size-class. Although seedling mass was usually greatest for large seeds and least for small seeds at each burial depth, little difference was observed in seedling height at shallow burial depths of 0-3 cm. The population shows a patchy and discontinuous distribution pattern. Population height increases with increasing sand depth. Also the density increases with increasing depth of sand in the desert; however, there is a steady decrease when the depth of sand is more than 100 cm. This result indicates that the depth of sand that is most suitable for the growth of Nitraria sphaerocarpa is 100 cm. The size of the population is significantly correlated with the sand depth, which increases with increasing depth in the desert.


Asunto(s)
Adaptación Fisiológica , Magnoliopsida/fisiología , Dióxido de Silicio , Viento , Clima Desértico , Plantones/crecimiento & desarrollo , Semillas/crecimiento & desarrollo
14.
Cell Res ; 16(7): 610-21, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16721357

RESUMEN

RNA polymerase (Pol) II transcription persists in TATA-box-binding protein (TBP)(-/-) mutant mouse embryos, indicating TBP-independent mechanisms for Pol II transcription in early development. TBP-related factor 3 (TRF3) has been proposed to substitute for TBP in TBP(-/-) mouse embryos. We examined the expression of TRF3 in maturing oocytes and early embryos and found that TRF3 was co-expressed with TBP in the meiotic oocytes and early embryos from the late one-cell stage onward. The amounts of TBP and TRF3 changed dynamically and correlated well with transcriptional activity. Chromatin immunoprecipitation (ChIP) assay revealed that different gene promoters in mouse embryonic stem (ES) cells recruited TRF3 and TBP selectively. Comparative analyses of TRF3 and TBP during cell cycle showed that both factors proceeded through cell cycle in a similar pace, except that TRF3 was slightly delayed than TBP in entering the nucleus when cells were exiting the M-phase. Data from expression and biochemical analyses therefore support the hypothesis that TRF3 plays a role in early mouse development. In addition, results from co-localization study suggest that TRF3 may be also involved in Pol I transcription.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Proteínas Nucleares/metabolismo , Proteínas Similares a la Proteína de Unión a TATA-Box/metabolismo , Animales , Embrión de Mamíferos/citología , Embrión de Mamíferos/fisiología , Femenino , Ratones , Ratones Noqueados , Células 3T3 NIH , Proteínas Nucleares/genética , Oocitos/fisiología , Regiones Promotoras Genéticas , Proteínas Similares a la Proteína de Unión a TATA-Box/genética , Proteína de Unión a TATA-Box/genética , Proteína de Unión a TATA-Box/metabolismo
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 31(1): 40-4, 2006 Feb.
Artículo en Chino | MEDLINE | ID: mdl-16562673

RESUMEN

OBJECTIVE: To screen for proteins interacting with ataxin-3 by yeast two-hybrid system 3, and to discuss the function of ataxin-3 and pathogenesis of spinocerebellar ataxia type 3 and Machado-Joseph disease (SCA3/MJD). METHODS: First we sub-cloned the full reading frame of both wild-type and mutant ataxin-3 into carrier pGBKT7 (ataxin-3-bait), and then screened human brain cDNA library with ataxin-3-bait. RESULTS: We found five positive clones in 6.5 x 10(6) transformers. After sequencing, we knew all of them were novel ataxin-3 interacting proteins. Three were corresponded to the known sequences coding the known proteins, which were human Rho GDP dissociation inhibitor alpha, small ubiquitin-like modifier 1, and human neuronal amiloride-sensitive cation channel 2. Another two of the five were unknown. CONCLUSION: Small ubiquitin-like modifier 1 probably interacted with ataxin-3, suggesting that the sumoylation probably participated in post-translation modifying of ataxin-3 and pathogenesis of SCA3/MJD.


Asunto(s)
Encéfalo/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Degeneraciones Espinocerebelosas/metabolismo , Ataxina-3 , Biblioteca de Genes , Humanos , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Mapeo de Interacción de Proteínas , Proteínas Represoras/genética , Degeneraciones Espinocerebelosas/genética , Técnicas del Sistema de Dos Híbridos , Levaduras/genética
16.
J Environ Sci (China) ; 17(5): 857-60, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16313019

RESUMEN

The purpose of this present study is to investigate the frequency and variation of sandstorm in Minqin Oasis. Using daily observational data of sandstorm and other meteorologic data from 1954 to 2000, we have illuminated the relationship between sandstorm, meteorological parameters and human activities. The results of the analysis show that the highest frequency of sandstorms occurrence and their duration mainly focus on March, April and May, especially in April. Most of sandstorms occur from midday to nightfall, but relative few appear from midnight to forenoon, which apparently correlates to the daily variations of atmospheric thermal stability within atmospheric boundary layer. Monthly mean and annual mean duration of sandstorms coincide well with the frequencies of sandstorm occurrence.


Asunto(s)
Desastres/estadística & datos numéricos , Dióxido de Silicio , Viento , China , Clima Desértico , Lluvia , Factores de Tiempo
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 21(1): 52-5, 2004 Feb.
Artículo en Chino | MEDLINE | ID: mdl-14767910

RESUMEN

OBJECTIVE: To construct a phosphatidylinositol 4-kinase beta (PI4K-beta) mutant with the 325th to 373rd amino acid codons deleted, and try to develop a simple method for constructing middle fragment deletion mutant. METHODS: In line with the mechanism of gene splicing by overlap extension(SOE), an additional PCR was used to get the PI4K-beta mutant in which the 325th to 373rd amino acid codons were deleted. Then the mutated gene was cloned into pCMV-Tag4A mammalian expression vector. RESULTS: A mutant with the 325th to 373rd amino acid codons deleted was constructed successfully. CONCLUSION: The improved SOE is a very effective and reliable method to construct middle fragment deletion mutant. It is worthy to be popularized.


Asunto(s)
1-Fosfatidilinositol 4-Quinasa/genética , Mutación/genética , Eliminación de Secuencia , Secuencia de Bases , Vectores Genéticos/genética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa/métodos , Ingeniería de Proteínas/métodos , Proteínas Recombinantes/genética
18.
Artículo en Chino | MEDLINE | ID: mdl-12007000

RESUMEN

Connexin 31 is a member of connexin family. The carboxy-terminal cytosolic domain of connexin 31 contains several potential phosphorylation sites. In this work, a yeast two-hybrid protein interaction screen have been used to identify proteins that bind to the carboxy-terminus of connexin 31, and the p11 protein, an unique member of S100 protein family, and one of the two subunits of the annexin II tetramer was isolated. Interestingly, from yeast two-hybrid AD's coding sequence, three different reading frames of p11 DNA sequence were found,which come from different AD plasmids. By constructing AD plasmids using p11 ORF or 5' UTR, the protein coding by p11 ORF bind to connexin 31, while polypeptides coding by three kinds of 5 UTR did not bind to connexin 31, suggesting a translational frameshift of p11 fusion protein. To construct baits by dividing connexin 31 C-terminus into two domain, the p11 binding domain of connexin 31 was found located between 206-237 codons. The plasmid Cx31CT-pGEX-4T-2 was constructed for expression and purification of GST-Cx31CT; and p11-pQE30 for expression and purification of 6xHis-p11. In vitro binding assay showed that recombinant Cx31 interacted with recombinant p11.


Asunto(s)
Anexina A2 , Proteínas de Unión al Calcio/metabolismo , Conexinas/metabolismo , Sistema de Lectura Ribosómico , Proteínas S100 , Regiones no Traducidas 5'/genética , Secuencia de Bases , Sitios de Unión/genética , Proteínas de Unión al Calcio/genética , Conexinas/genética , ADN Complementario/genética , Genes Reporteros/genética , Datos de Secuencia Molecular , Unión Proteica , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Saccharomyces cerevisiae/genética , Homología de Secuencia de Ácido Nucleico , Técnicas del Sistema de Dos Híbridos
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