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1.
Nat Commun ; 14(1): 733, 2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36759612

RESUMEN

Superconductivity in the cuprates is found to be intertwined with charge and spin density waves. Determining the interactions between the different types of order is crucial for understanding these important materials. Here, we elucidate the role of the charge density wave (CDW) in the prototypical cuprate La1.885Sr0.115CuO4, by studying the effects of large magnetic fields (H) up to 24 Tesla. At low temperatures (T), the observed CDW peaks reveal two distinct regions in the material: a majority phase with short-range CDW coexisting with superconductivity, and a minority phase with longer-range CDW coexisting with static spin density wave (SDW). With increasing magnetic field, the CDW first grows smoothly in a manner similar to the SDW. However, at high fields we discover a sudden increase in the CDW amplitude upon entering the vortex-liquid state. Our results signify strong coupling of the CDW to mobile superconducting vortices and link enhanced CDW amplitude with local superconducting pairing across the H - T phase diagram.

2.
Clin. transl. oncol. (Print) ; 24(1): 104-111, enero 2022.
Artículo en Inglés | IBECS | ID: ibc-203419

RESUMEN

PurposeImmunotherapy is now a first-line treatment for metastatic non-small cell lung cancer (NSCLC) and melanomaQuery. It is important to understand the relationship between immunotherapy and radiation to the brain. The aim of this study was to assess the role of stereotactic radiosurgery (SRS) or WBRT in addition to immunotherapy in patients with melanoma or NSCLC metastatic to the brain.Methods/patientsUsing the National Cancer Database, 2951 patients with NSCLC and 936 patients with melanoma treated with immunotherapy were identified. Patients were classified as having received immunotherapy alone, immunotherapy with SRS, or immunotherapy with whole-brain radiation therapy (WBRT). Kaplan–Meier, multivariate Cox regression analyses, and propensity matching were performed to evaluate the impact of adding SRS to immunotherapy on overall survival (OS). Immortal survival bias was accounted for by only including patients who received radiation before immunotherapy and time zero was defined as the start of immunotherapy.Results205(6.9%) and 75(8.0%) patients received immunotherapy with no radiation, 822(27.9%) and 326(34.8%) received SRS and immunotherapy, and 1924(65.2%) and 535(57.2%) received WBRT and immunotherapy for NSCLC and melanoma, respectively. Adding SRS to immunotherapy was associated with improved OS in multivariate analyses (NSCLC HR = 0.81, 95% CI 0.66–0.99, p = 0.044; melanoma HR = 0.63, 95% CI 0.45–0.90, p = 0.011). The addition of WBRT to immunotherapy did not improve OS in patients with melanoma nor NSCLC.ConclusionsThis analysis suggests that treatment with SRS and immunotherapy is associated with improved OS compared to immunotherapy alone for patients with melanoma or NSCLC metastatic to the brain.


Asunto(s)
Humanos , Ciencias de la Salud , Radiocirugia , Inmunoterapia , Melanoma , Neoplasias Pulmonares , Neoplasias , Metástasis de la Neoplasia
3.
Clin Transl Oncol ; 24(1): 104-111, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34236616

RESUMEN

PURPOSE: Immunotherapy is now a first-line treatment for metastatic non-small cell lung cancer (NSCLC) and melanomaQuery. It is important to understand the relationship between immunotherapy and radiation to the brain. The aim of this study was to assess the role of stereotactic radiosurgery (SRS) or WBRT in addition to immunotherapy in patients with melanoma or NSCLC metastatic to the brain. METHODS/PATIENTS: Using the National Cancer Database, 2951 patients with NSCLC and 936 patients with melanoma treated with immunotherapy were identified. Patients were classified as having received immunotherapy alone, immunotherapy with SRS, or immunotherapy with whole-brain radiation therapy (WBRT). Kaplan-Meier, multivariate Cox regression analyses, and propensity matching were performed to evaluate the impact of adding SRS to immunotherapy on overall survival (OS). Immortal survival bias was accounted for by only including patients who received radiation before immunotherapy and time zero was defined as the start of immunotherapy. RESULTS: 205(6.9%) and 75(8.0%) patients received immunotherapy with no radiation, 822(27.9%) and 326(34.8%) received SRS and immunotherapy, and 1924(65.2%) and 535(57.2%) received WBRT and immunotherapy for NSCLC and melanoma, respectively. Adding SRS to immunotherapy was associated with improved OS in multivariate analyses (NSCLC HR = 0.81, 95% CI 0.66-0.99, p = 0.044; melanoma HR = 0.63, 95% CI 0.45-0.90, p = 0.011). The addition of WBRT to immunotherapy did not improve OS in patients with melanoma nor NSCLC. CONCLUSIONS: This analysis suggests that treatment with SRS and immunotherapy is associated with improved OS compared to immunotherapy alone for patients with melanoma or NSCLC metastatic to the brain.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/terapia , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/terapia , Inmunoterapia , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/terapia , Melanoma/mortalidad , Melanoma/terapia , Radiocirugia , Anciano , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/secundario , Terapia Combinada , Bases de Datos Factuales , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Melanoma/secundario , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Estados Unidos
4.
Neoplasma ; 67(5): 1002-1011, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32453597

RESUMEN

Renal cell carcinoma (RCC) is the most common malignant tumor of the kidney. In this study, we investigated the role of miR-346 in RCC cells under hypoxia. OS-RC-2 and 786-O cells were cultured in 1% O2 or normal oxygen. Cell proliferation, migration, and invasion abilities were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, transwell migration, and invasion assays, respectively. Quantitative real-time PCR (qRT-PCR) was performed to detect the expression of miR-346 and N-myc downstream-regulated gene 2 (NDRG2). Then bioinformatics analysis, dual-luciferase reporter assay, and RNA immunoprecipitation were carried out to determine the relationship between miR-346 and NDRG2. The protein expression of NDRG2 was detected by western blot assay. Hypoxia promoted cell proliferation, migration, and invasion in OS-RC-2 and 786-O cells. Meanwhile, we found that miR-346 was upregulated in RCC cells under hypoxia as relative to normoxia. miR-346 deletion could decrease the viability, migration, and invasion abilities of RCC cells under hypoxia. Besides, our data demonstrated that NDRG2 was a target gene of miR-346. The expression of NDRG2 in OS-RC-2 and 786-O cells was lower under hypoxia than under normal oxygen conditions. Moreover, NDRG2 overexpression could inhibit cell proliferation, migration, and invasion in RCC cells under hypoxia. And NDRG2 silencing reversed the inhibitory effects of the miR-346 inhibitor on the viability, migration, and invasion abilities of RCC cells in hypoxia conditions. miR-346 promoted the viability, migration, and invasion of RCC cells under hypoxia by targeting NDRG2.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , MicroARNs/genética , Proteínas Supresoras de Tumor/genética , Carcinoma de Células Renales/genética , Hipoxia de la Célula , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Humanos , Neoplasias Renales/genética
5.
J Viral Hepat ; 25(9): 1017-1025, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29624802

RESUMEN

The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large-sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)-positive chronic HBV infection (n = 588), HBeAg-positive chronic hepatitis B (n = 596), and HBeAg-negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%-90% confidence interval: 3.52 log10 IU/mL-4.99 log10 IU/mL]) in patients with HBeAg-positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg-positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg-negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg-positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg-negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/patología , Cirrosis Hepática/patología , Suero/química , Adulto , Alanina Transaminasa/sangre , China , ADN Viral/sangre , Femenino , Antígenos e de la Hepatitis B/sangre , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
6.
Zhonghua Yi Xue Za Zhi ; 97(44): 3492-3497, 2017 Nov 28.
Artículo en Chino | MEDLINE | ID: mdl-29275586

RESUMEN

Objective: To explore a relationship between screening and incidence for colorectal cancer (CRC). Methods: Medline, Scopus, BIOSIS Previews, and the Cochrane Library were searched for studies, which included any randomized controlled trial (RCT) about CRC screening with a report on using endoscopy in screening arms and a usual care in control arms. Results: Nine qualified trials, four one-time and five two-or-more-time screening programs, were included in this review with 997 131 persons randomized and a median follow-up of 10-28 years. In an intention-to-screen analysis, screening was associated with a reduced incidence of advanced CRCs by 10%-60%. Compared with control groups, incidence of CRC firstly increased and then decreased following a screening procedure. Five RCT with six screening arms reported incidences at different follow-up time points, and the incidence ratios at the last time of follow-up were 0.96 (95%CI: 0.86-1.06), 0.80 (95%CI: 0.70-0.92), 1.02 (95%CI: 0.91-1.14), 0.80 (95%CI: 0.70-0.90), 0.83 (95%CI: 0.73-0.94) and 0.94 (95%CI: 0.85-1.05) at the 9.0th, 10.9th, 13.0th, 18.0th, 18.0th, and 19.5th year after baseline, respectively. Compared with population-based screening, people in the hospital/clinic-based screenings had more benefits from CRC incidence reduction, particularly for those with high endoscopy rates, more lesions detected and resected by screening. Conclusions: This study indicates that screening is likely associated with reduction of CRC incidence after 10 years since baseline screening, and this reduction seems to be highly affected by CRC risk of population screened, screening procedure program, and compliance to screening program including accepting endoscopy.


Asunto(s)
Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Neoplasias del Colon , Neoplasias Colorrectales/epidemiología , Incidencia , Tamizaje Masivo
7.
Zhonghua Yi Xue Za Zhi ; 97(13): 1024-1029, 2017 Apr 04.
Artículo en Chino | MEDLINE | ID: mdl-28395423

RESUMEN

Objective: To explore a registry method for acute cardiovascular events in large-scale fields across China. Methods: This study was based on a community-based Kazakh cohort, including 1 668 persons with complete baseline data, conducted in Altay, Xinjiang. Acute cardiovascular events included acute myocardial infarction(ICD-10: I21-I22), sudden cardiac death (I46.1), and incident stroke (I60-I64) that occurred during the period from Oct 1, 2012 to Jun 30, 2016. There were three stages, a hospital-based search for checking medical records of inpatients in all four local hospitals, a community-based supplementary registry, and an extra survey for reducing false negatives, to complete this registry. The incidence referred to all events within one year per 100 000 people and mortality rate was the number of fatal events within 28 days per 100 000 people. The incidence and mortality was standardized with the weights from distribution of age and gender in the Sixth National Census of China. Results: Forty two cases with 46 acute cardiovascular events including 7 acute myocardial infarctions, 3 sudden cardiac deaths, and 36 incident strokes were found. The ratio of events was 3.6∶1 for stroke and heart attacks and this ratio was 1.6∶1 for ischemic or hemorrhagic strokes. A total of 28(60.9%) events and 18(39.1%) events were collected in the hospitals and by community-based supplementary registry physicians, respectively. False negatives were not found at the last stage. The crude and standardized incidence rates were 742 and 926 per 100 000 people and the related mortality rates were 194 and 272 per 100 000 people, respectively. Conclusion: Primary Care physicians are"net bottom" of a monitoring system which needs to combine preventive and clinical medicine with all kinds of governmental resources including health and social benefit.


Asunto(s)
Infarto del Miocardio/epidemiología , Sistema de Registros , Accidente Cerebrovascular/epidemiología , China , Humanos , Incidencia , Proyectos Piloto
8.
Genet Mol Res ; 15(4)2016 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-27813550

RESUMEN

The genetic diversity and spatial autocorrelation of Toona ciliata populations were analyzed with eight microsatellite markers to determine an appropriate sampling strategy for the effective conservation of natural T. ciliata populations. The average number of alleles and effective number of alleles were 6.1 and 2.7, respectively. The mean expected heterozygosity was 0.6006. Overall, 96.6% of the genetic variation existed in two natural populations, which was concluded from the coefficient of genetic differentiation (FST = 0.1854). Therefore, two natural populations were selected for conservation and sampling. The mean effective number of alleles and expected heterozygosity increased with increasing sample number. The mean expected heterozygosity tended to be stable when the sampling number exceeded 30. The maximum value of expected heterozygosity was 0.4770 when the sampling number was 45. Therefore, 45 sampled individuals were sufficient for conservation and sampling. Similarity relationships existed between individuals within 240 m. There were marked differences among individuals over 240 m away. The distance between individuals exceeded 240 m when natural populations were sampled.


Asunto(s)
Técnicas Genéticas , Meliaceae/genética , Alelos , Análisis por Conglomerados , Variación Genética , Genética de Población , Geografía , Heterocigoto , Filogenia
9.
J Clin Virol ; 72: 85-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26469738

RESUMEN

This report describes a pediatric case of severe fever with thrombocytopenia syndrome (SFTS), which is an emerging disease that is caused by a novel bunyavirus. Interestingly, the previously reported SFTS cases typically involved elderly patients, while our case involved a 5-year-old child from Zhejiang Province, China. In this report, we describe our investigation of the clinical and epidemiological characteristics of this case, to improve our understanding of this emerging disease. Our principle finding was that the present case's clinical symptoms were milder than those that have been reported in adult cases of SFTS. Therefore, we recommend more careful screening of pediatric patients who present with mild symptoms that are consistent with SFTS.


Asunto(s)
Orthobunyavirus/aislamiento & purificación , Fiebre por Flebótomos/diagnóstico , Fiebre por Flebótomos/patología , Preescolar , China , Femenino , Humanos
10.
Acta Hortic ; 1061: 281-288, 2015 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-27158184

RESUMEN

Many species of berries are nutritious food and offer health benefits. However, among the different types of berries, information on health effects of American elderberries (Sambucus nigra subsp. canadensis) has been lacking and little is known about whether elderberry consumption can confer neuroprotective effects on the central nervous system. Microglial cells constitute a unique class of immune cells and exhibit characteristic properties to carry out multifunctional duties in the brain. Activation of microglial cells has been implicated in brain injury and in many types of neurodegenerative diseases. Our recent studies demonstrated the ability for endotoxin (lipopolysaccharide, LPS) and interferon gamma (IFNγ) to induce reactive oxygen species (ROS) and nitric oxide (NO) in murine microglial cells (BV-2) through activating NADPH oxidase and the MAPK pathways. In this study, BV-2 microglial cells were used to examine effects of elderberry juice obtained from different genotypes on oxidative and inflammatory responses induced by LPS and IFNγ. Results show that 'Wyldewood' extract demonstrated antioxidant properties by inhibiting IFNγ-induced ROS production and p-ERK1/2 expression. On the other hand, most juice extracts exerted small effects on LPS-induced NO production and some extracts showed an increase in NO production upon stimulation with IFNγ. The disparity of responses on ROS and NO production from different extracts suggests possible presence of unknown endogenous factor(s) in the extract in promoting the IFNγ-induced iNOS synthesis pathway.

11.
Genet Mol Res ; 14(4): 17799-808, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26782425

RESUMEN

We investigated the effect of neural stem cells (NSC) and erythropoietin (EPO) on axon regeneration in adult rats with transected spinal cord injury, and provided an experimental basis for clinical treatment. Forty Wistar rats with T10-transected spinal cord injury were randomly divided into four groups of ten rats: a control group (group A), an NSC-transplant group (group B), an NSC-transplant and EPO group (group C), and an EPO group (group D). Biotinylated dextran amines (BDA) anterograde corticospinal cord neuronal tracing and Fluoro-Gold (FG) retrograde tracing were carried out at the 8th week after operation to observe the regeneration of nerve fibers. The Basso, Beattie, and Bresnahan (BBB) locomotor score was used to evaluate restoration. 1) BDA and FG immunofluorescence staining: in group C, a large number of regenerated axons were observed and some penetrated the injured area. In group B, only a small number of regenerated axons were observed and none penetrated the injured area. In group D, only sporadic regenerated nerve fibers were observed occasionally, while in group A, no axonal regeneration was observed. In group C, a small number of cones and axons emitted yellow fluorescence, and no FG-labeled cells were observed in the other groups. 2) The BBB scores for group C were higher than those for the other groups, and the differences were statistically significance (P < 0.05). NSC transplantation combined with EPO intraperitoneal injection may benefit axon regeneration in rats with transected spinal cord injury, and accelerate the functional recovery of the hindlimb locomotor.


Asunto(s)
Eritropoyetina/administración & dosificación , Regeneración Nerviosa/fisiología , Células-Madre Neurales/trasplante , Traumatismos de la Médula Espinal/terapia , Animales , Axones/fisiología , Humanos , Ratas , Recuperación de la Función , Traumatismos de la Médula Espinal/fisiopatología
12.
Epidemiol Infect ; 143(4): 851-6, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24866248

RESUMEN

Severe fever with thrombocytopenia syndrome virus (SFTSV) has been prevalent for some time in China and it was first identified in 2010. However, the seroprevalence of SFTSV in the general population in southeastern China and risk factors associated with the infection are currently unclear. Blood samples were collected from seven counties across Zhejiang province and tested for the presence of SFTSV-specific IgG antibodies by ELISA. A total of 1380 blood samples were collected of which 5·51% were seropositive for SFTSV with seroprevalence varying significantly between sites. Seroprevalence of SFTSV in people who were family members of the patient, lived in the same village as the patient, or lived in a different village than the patient varied significantly. There was significant difference in seroprevalence between participants who bred domestic animals and participants who did not. Domestic animals are probably potential reservoir hosts and contact with domestic animals may be a transmission route of SFTSV.


Asunto(s)
Infecciones por Bunyaviridae/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Infecciones por Bunyaviridae/etiología , Infecciones por Bunyaviridae/virología , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Phlebovirus , Factores de Riesgo , Estudios Seroepidemiológicos , Adulto Joven
13.
Genet Mol Res ; 13(2): 4579-90, 2014 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-25036507

RESUMEN

Our objective was to examine the genetic diversity of central and peripheral populations of Toona ciliata var. pubescens, to elucidate whether the central-peripheral hypothesis applies to these populations. We analyzed 392 individuals from nine natural populations using eight pairs of polymorphic SSR primers. The results showed that the mean numbers of observed and expected alleles in peripheral populations were higher than in central populations. Common widespread and rare local (RL) alleles were observed in all populations. However, common local alleles were found in five populations and rare widespread alleles were only found in three. The total numbers of the four types of alleles were higher in peripheral than in central populations, and the quantity of the RL allele was obviously higher in the peripheral populations than in the central populations. Both the observed and expected heterozygosities were higher in peripheral populations compared with the central populations. The coefficient of gene differentiation of the peripheral populations was 0.3045, which was significantly higher than that of the central populations. The gene flow between central populations was greater than one, but less than one between peripheral populations. This indicates that frequent gene flow exists between central populations, while terrain and habitat fragmentation prevent gene flow between peripheral populations. A Mantel test indicated that there was no relationship between genetic and geographical distance of T. ciliata var. pubescens.


Asunto(s)
Especies en Peligro de Extinción , Variación Genética , Meliaceae/genética , Flujo Génico , Genes de Plantas , Heterogeneidad Genética , Endogamia , Meliaceae/clasificación , Repeticiones de Microsatélite
14.
Genet Mol Res ; 12(3): 3689-97, 2013 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-23546979

RESUMEN

The genetic diversity of 10 Machilus thunbergii populations in eastern China was analyzed using inter-simple sequence repeat markers. The populations showed high genetic diversity, with an overall population genetic diversity of 0.2343. Genetic diversity varied largely among populations, and populations with the highest genetic diversity were mainly from the eastern and western parts of the natural distribution area. Small populations, lack of effective gene flow, and fragmentation of habitats have led to greater genetic differentiation among populations, with 41.18% of genetic variation existing among populations. Unweighted pair-group method with arithmetic mean cluster analysis indicated that populations distributed between latitudes 25° and 31°N were clustered together and should be prioritized for in situ conservation. Northern, eastern, and southern populations were located in peripheral areas of the distribution range and were clustered separately. Collection of distinctive germplasm from peripheral populations should be promoted and ex situ conservation of elite germplasm should be implemented.


Asunto(s)
Especies en Peligro de Extinción , Variación Genética , Genética de Población , Lauraceae/genética , China , Análisis por Conglomerados , Conservación de los Recursos Naturales , ADN de Plantas/genética , Ecosistema , Flujo Génico , Sitios Genéticos , Repeticiones de Microsatélite , Filogenia , Reacción en Cadena de la Polimerasa , Árboles/genética
15.
Genet Mol Res ; 11(4): 4411-7, 2012 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-23079981

RESUMEN

Toona ciliata var. pubescens is considered an endangered tree species native to China. In order to help develop a conservation program for this species, we evaluated its genetic diversity and population genetics. We isolated microsatellite DNA loci using streptavidin beads. A genomic library, enriched with microsatellites, was constructed and screened by sequencing. We detected 8 polymorphic microsatellite loci from the tree tissue samples. The population of T. ciliata var. pubescens used in this study is located within the Guanshan National Nature Reserve, Jiangxi Province, China. Sixty-five individuals were collected for the study. The Guanshan population was split into two subpopulations due to terrain. The number of alleles per locus ranged from 2 to 6, with expected heterozygosity from 0.2386 to 0.6772. Four of the 8 loci, except loci Tc02, Tc04, Tc05, and Tc07 showed no significant departure from Hardy-Weinberg equilibrium. The mean observed heterozygosity was 0.59. The average coefficient of genetic differentiation between the two subpopulations was quite low (F(ST) = 0.0235). The level of gene flow (N(m)) was 10.39, reflecting a high degree of gene flow between the two subpopulations.


Asunto(s)
Meliaceae/genética , Repeticiones de Microsatélite , Alelos , Secuencia de Bases , ADN de Plantas/genética , ADN de Plantas/aislamiento & purificación , Especies en Peligro de Extinción , Genética de Población , Polimorfismo Genético
16.
Chemosphere ; 76(8): 1114-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19423148

RESUMEN

This study investigated the levels and potential transformation of matrix-bound phosphine in the intertidal sediments (0-5cm) of the Yangtze Estuary. Matrix-bound phosphine concentrations in sediments ranged from 0.65 to 3.25ngkg(-1), with an annual average of 1.53ngkg(-1). In freshwater sediments, the concentrations of matrix-bound phosphine were significantly higher than in the brackish sediments. The maximum concentrations of matrix-bound phosphine appeared in July (1.17-3.25ngkg(-1)), followed by May (0.92-3.01ngkg(-1)), November (0.65-2.41ngkg(-1)) and January (0.51-1.42ngkg(-1)). Matrix-bound phosphine derived probably from the mechanochemical reduction of apatite-bound phosphate and the microbial conversion of organic phosphorus in the intertidal sediments. Its spatial and seasonal distributions, however, were regulated by salinity and sediment temperature. Compared with other aquatic systems (e.g. rivers, lakes and coastal seas), a low level of matrix-bound phosphine was observed in the intertidal sediments, probably implicating a relatively rapid turnover of phosphine in the system.


Asunto(s)
Sedimentos Geológicos/análisis , Fosfinas/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Agua Dulce/análisis , Ríos , Estaciones del Año
17.
Mol Genet Genomics ; 270(3): 234-42, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14513364

RESUMEN

The availability of huge amounts of rice genome sequence now permits large-scale analysis of the structure and molecular characteristics of the previously identified transposase-encoding Rim2 (also called Hipa) element, which is transcriptionally activated by infection with the fungal pathogen Magnaporthe grisea and by treatment with the corresponding fungal elicitor. Based on genomic cloning and data mining from 230 Mb of rice genome sequence, 347 Rim2 elements, with an average size of 5.8 kb, were identified. This indicates that an estimated total of 600-700 Rim2 elements are present in the whole genome. Rim2 insertions occur non-randomly on the chromosomes, as visualized by fluorescence in situ hybridization. The elements harbor 16-bp terminal inverted repeats with the core sequence CACTG, 16-bp sub-terminal repeats, internal variable regions, 3-bp target sequence duplications in the flanking regions, and genes coding for Rim2 proteins (the putative transposase) and hydroxyproline-rich glycoproteins. High levels of insertion into genic regions are observed for members of this family, and the transposition history of the family can be deduced from the high level of shared sequences and analysis of repeat target sites of the elements. Phylogenetic analysis indicates that the putative RIM2 proteins fall into a subgroup distinct from the TNP2-like subgroup of transposases. Southern hybridization with genomic DNA from monocotyledonous and dicotyledonous plants demonstrates that the RIM2-coding sequence is unique to the Oryza genome. Our results demonstrate that the Rim2 elements from rice belong to a distinct superfamily of CACTA-like elements with evolutionary diversity.


Asunto(s)
Proteínas Portadoras/genética , Elementos Transponibles de ADN , Proteínas de Escherichia coli/genética , Genoma de Planta , Proteínas Nucleares/genética , Oryza/genética , Proteínas de Plantas/genética , Transposasas , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Secuencia Conservada , Elementos Transponibles de ADN/genética , Escherichia coli/genética , Datos de Secuencia Molecular , Mutagénesis Insercional , Oryza/clasificación , Filogenia , Secuencias Repetitivas de Ácidos Nucleicos , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
18.
Life Sci ; 68(11): 1259-70, 2001 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-11233993

RESUMEN

Ilex latifolia is widely used as an ingredient to prepare traditional beverage drinks in southern China. In fact, various Ilex species have been used in Chinese folk medicine to treat coronary heart diseases. The mode of action is believed to be mediated by their coronary vasodilative effects. In this study, the water extract of the leaves of Ilex latifolia (IK-TP) was shown to increase the contractility and decrease the frequency of contraction in an isolated rat heart perfusion system. IK-TP was found to inhibit Na+/K+-ATPase activities in rat heart sarcolemma, rat brain microsomes and a purified enzyme from porcine cerebral cortex. IK-TP also inhibited Ca2+-dependent ATPase at a similar dose. Following exposure of the isolated rat heart to IK-TP at a dose that produces pronounced cardiac effects, inhibition of Na+/K+-ATPase activity can be readily detected in the heart. This study suggests the presence of ATPase inhibitory compounds in Ilex latifolia with specificities different from that of ouabain.


Asunto(s)
Medicamentos Herbarios Chinos , Inhibidores Enzimáticos/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Contracción Miocárdica/efectos de los fármacos , Extractos Vegetales/farmacología , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Animales , Encéfalo/enzimología , Encéfalo/ultraestructura , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Cardiotónicos/farmacología , Corteza Cerebral/enzimología , Cinética , Masculino , Microsomas/enzimología , Miocardio/enzimología , Ratas , Ratas Sprague-Dawley , Sarcolema/enzimología , Porcinos
19.
Zhongguo Zhong Yao Za Zhi ; 26(12): 853-6, 2001 Dec.
Artículo en Chino | MEDLINE | ID: mdl-12776338

RESUMEN

OBJECTIVE: To study the effects of Kudingcha (Ilex latifolia Thunb., IL) on the isolated guinea pig tracheal smooth muscle in vitro. METHOD: By obtaining CaCl2 and Histamine accumulative dose-response curves, to observe the influences of IL on the contraction of tracheal strips induced by calcium and some asthmogenic mediators. RESULT: CaCl2 and histamine caused significant contraction of tracheal smooth muscle and pD2 was 3.55 and 5.34 respectively. After incubated with IL, the dose-response curves of CaCl2 and histamine were significantly shifted to the right, and the maximal contractile force was reduced. IL could also inhibit isolated tracheal strip contraction induced by acetylcholine 3 x 10(-6) mol.L-1 and histamine 3 x 10(-6) mol.L-1, and IC50 was 0.16 mg.ml-1 and 0.21 mg.ml-1. CONCLUSION: Kudingcha has significant dilated effects on tracheal smooth muscle.


Asunto(s)
Broncodilatadores/farmacología , Medicamentos Herbarios Chinos/farmacología , Ilex/química , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Animales , Broncodilatadores/aislamiento & purificación , Cloruro de Calcio/antagonistas & inhibidores , Medicamentos Herbarios Chinos/aislamiento & purificación , Cobayas , Antagonistas de los Receptores Histamínicos/farmacología , Técnicas In Vitro , Masculino , Plantas Medicinales/química , Tráquea/efectos de los fármacos
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