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1.
J Environ Manage ; 351: 119977, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38160549

RESUMEN

Moso bamboo (Phyllostachys edulis) is a valuable nontimber forestry product with a biennial cycle, producing abundant bamboo shoots within one year (on-year) and few shoots within the following year (off-year). Moso bamboo plants undergo clonal reproduction, resulting in similar genetic backgrounds. However, the number of moso bamboo shoots produced each year varies. Despite this variation, the impact of soil nutrients and the root microbiome on the biennial bearing of moso bamboo is poorly understood. We collected 139 soil samples and determined 14 major physicochemical properties of the rhizosphere, rhizoplane, and bulk soil in different seasons (i.e., the growing and deciduous seasons) and different years (i.e., on- and off-years). Based on 16S rRNA and metagenomic sequencing, major variations were found in the rhizospheric microbial composition during different seasons and years in the moso bamboo forest. Environmental driver analysis revealed that essential nutrients (i.e., SOC, TOC, TN, P, and NH4+) were the main drivers of the soil microbial community composition and were correlated with the on- and off-year cycles. Moreover, 19 MAGs were identified as important biomarkers that could distinguish on- and off-years. We found that both season and year influenced both the microbial community structure and functional pathways through the biosynthesis of nutrients that potentially interact with the moso bamboo growth rhythm, especially the on-year root-associated microbiome, which had a greater abundance of specific nutrients such as gibberellins and vitamin B6. This work provides a dynamic perspective of the differential responses of various on- and off-year microbial communities and enhances our understanding of bamboo soil microbiome biodiversity and stability.


Asunto(s)
Poaceae , Rizosfera , ARN Ribosómico 16S/genética , Bosques , Suelo/química
2.
J Sci Food Agric ; 103(13): 6416-6428, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37209269

RESUMEN

BACKGROUND: Phytophthora infestans causes late blight, threatening potato production. The tropane alkaloid scopolamine from some industrial plants (Datura, Atropa, etc.) has a broad-spectrum bacteriostatic effect, but its effect on P. infestans is unknown. RESULTS: In the present study, scopolamine inhibited the mycelial growth of phytopathogenic oomycete P. infestans, and the half-maximal inhibitory concentration (IC50 ) was 4.25 g L-1 . The sporangia germination rates were 61.43%, 16.16%, and 3.99% at concentrations of zero (control), 0.5 IC50 , and IC50 , respectively. The sporangia viability of P. infestans was significantly reduced after scopolamine treatment through propidium iodide and fluorescein diacetate staining, speculating that scopolamine destroyed cell membrane integrity. The detached potato tuber experiment demonstrated that scopolamine lessened the pathogenicity of P. infestans in potato tubers. Under stress conditions, scopolamine showed good inhibition of P. infestans, indicating that scopolamine could be used in multiple adverse conditions. The combination effect of scopolamine and the chemical pesticide Infinito on P. infestans was more effective than the use of scopolamine or Infinito alone. Moreover, transcriptome analysis suggested that scopolamine leaded to a downregulation of most P. infestans genes, functioning in cell growth, cell metabolism, and pathogenicity. CONCLUSION: To our knowledge, this is the first study to detect scopolamine inhibitory activity against P. infestans. Also, our findings highlight the potential of scopolamine as an eco-friendly option for controlling late blight in the future. © 2023 Society of Chemical Industry.

3.
J Environ Qual ; 43(6): 1953-62, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25602212

RESUMEN

To date, little is known about the effects of heavy metals on the sorption of organic contaminants by phytoplankton. In this study, the effects of Cu, Cd, and Ag on the sorption of polycyclic aromatic hydrocarbons (PAHs) by were studied. Phenanthrene sorption was facilitated by low concentrations of metal salts (≤20 µmol L) and was significantly suppressed in the presence of 50 to 200 µmol L metal salts and rebounded and exceeded the control in the presence of 500 to 5000 µmol L Cu(NO) and AgNO, respectively. Although the ionic strengths of the solutions were the same, phenanthrene sorption was different in the presence of the same concentrations of Cu(NO) and Cd(NO) especially in the high concentration range. In the high concentration range, Ag was much more effective than Cu and Cd to increase phenanthrene sorption. In contrast to phenanthrene, sorption of both pyrene and benzo[a]pyrene increased dramatically in the presence of Cu(NO). The cation-π interactions between the metal cations and PAHs facilitated the sorption of the PAHs. Sorption enhancement of the PAHs caused by the cation-π interactions increased with the softness order of the metals (Cd < Cu < Ag) and the π donor strength order of the PAHs (phenanthrene < pyrene < benzo[a]pyrene). This study suggests that sorption of PAHs by cyanobacteria can be significantly altered by concentrations and properties of both heavy metals and PAHs.

4.
Acta Biomater ; 182: 171-187, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38759743

RESUMEN

Photodamage is one of the most common causes of skin injury. High molecular weight hyaluronic acid (HHA) has shown immense potential in the treatment of skin photodamage by virtue of its anti-inflammatory, reparative, and antioxidative properties. However, due to its large molecular structure of HHA, HHA solution could only form a protective film on the skin surface in conventional application, failing to effectively penetrate the skin, which necessitates the development of new delivery strategies. Liposomes, with a structure similar to biological membranes, have garnered extensive attention as transdermal drug delivery carriers because of their advantages in permeability, dermal compatibility, and biosafety. Herein, we have developed a HHA-liposome transdermal system (HHL) by embedding HHA into the liposome structure using reverse evaporation, high-speed homogenization, and micro-jet techniques. The effective penetration and long-term residence of HHA in skin tissue were multidimensionally verified, and the kinetics of HHA in the skin were extensively studied. Moreover, it was demonstrated that HHL significantly strengthened the activity of human keratinocytes and effectively inhibits photo-induced cellular aging in vitro. Furthermore, a murine model of acute skin injury induced by laser ablation was established, where the transdermal system showed significant anti-inflammatory and immunosuppressive properties, promoting skin proliferation and scar repair, thereby demonstrating immense potential in accelerating skin wound healing. Meanwhile, HHL significantly ameliorated skin barrier dysfunction caused by simulated sunlight exposure, inhibited skin erythema, inflammatory responses, and oxidative stress, and promoted collagen expression in a chronic photodamage skin model. Therefore, this transdermal delivery system with biocompatibility represents a promising new strategy for the non-invasive application of HHA in skin photodamage, revealing the significant potential for clinical translation and broad application prospects. STATEMENT OF SIGNIFICANCE: The transdermal system utilizing hyaluronic acid-based liposomes enhances skin permeability and retains high molecular weight hyaluronic acid (HHL). In vitro experiments with human keratinocytes demonstrate significant skin repair effects of HHL and its effective inhibition of cellular aging. In an acute photodamage model, HHL exhibits stronger anti-inflammatory and immunosuppressive properties, promoting skin proliferation and scar repair. In a chronic photodamage model, HHL significantly improves skin barrier dysfunction, reduces oxidative stress induced by simulated sunlight, and enhances collagen expression.


Asunto(s)
Administración Cutánea , Ácido Hialurónico , Liposomas , Envejecimiento de la Piel , Piel , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Liposomas/química , Animales , Humanos , Piel/patología , Piel/efectos de los fármacos , Piel/metabolismo , Envejecimiento de la Piel/efectos de los fármacos , Ratones , Peso Molecular , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Sistemas de Liberación de Medicamentos , Células HaCaT
5.
Viruses ; 15(4)2023 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-37112889

RESUMEN

Amphioxus species are considered living fossils and are important in the evolutionary study of chordates and vertebrates. To explore viral homologous sequences, a high-quality annotated genome of the Beihai amphioxus (Branchiostoma belcheri beihai) was examined using virus sequence queries. In this study, 347 homologous fragments (HFs) of viruses were identified in the genome of B. belcheri beihai, of which most were observed on 21 genome assembly scaffolds. HFs were preferentially located within protein-coding genes, particularly in their CDS regions and promoters. A range of amphioxus genes with a high frequency of HFs is proposed, including histone-related genes that are homologous to the Histone or Histone H2B domains of viruses. Together, this comprehensive analysis of viral HFs provides insights into the neglected role of viral integration in the evolution of amphioxus.


Asunto(s)
Anfioxos , Animales , Anfioxos/genética , Histonas/genética , Genoma , Genómica , Filogenia
6.
Environ Sci Pollut Res Int ; 29(17): 24716-24725, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34826083

RESUMEN

Owing to rapid socio-economic development in China, trace metal emissions have increased and lakes even in remote areas have experienced marked changes in the last century. However, there are limited studies revealing long-term trends, anthropogenic fluxes, and spatial characteristics of trace metals in lakes. In this study, we present a geochemical record from Lake Qinghai in the northeastern Qinghai-Tibetan Plateau and reconstruct trace metal pollution history during the last two centuries. The lacustrine sediment core was dated by 137Cs and 210Pb, and sediments deposited prior to the 1850s were selected as the pre-industrial background. Factor analysis and enrichment factor indicated Cr, Cu, and Ni generally originated from natural sources, while Cd, Pb, and Zn have been influenced by human contamination since the mid-1980s. The anthropogenic Cd mainly derived from non-ferrous metal smelting in Gansu Province, and fluxes to Lake Qinghai sharply increased after the mid-1980s. The metal reconstruction is similar to other lake sediment records from China and corresponds well with rapid economic development in China. The spatial pattern of anthropogenic Cd fluxes to lakes is primarily attributed to regional industrial emission, phosphate fertilizers, and manure applied in agriculture.


Asunto(s)
Metales Pesados , Oligoelementos , Contaminantes Químicos del Agua , Cadmio/análisis , China , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Humanos , Lagos , Plomo/análisis , Metales Pesados/análisis , Tibet , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis
7.
Gigascience ; 112022 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-36310246

RESUMEN

Bamboo, the fast-growing grass plant, and rattan, the spiky climbing palm, are both essential forest resources that have been closely linked with human lives, livelihoods and material culture since ancient times. To promote genetic and genomic research in bamboo and rattan, a comprehensive and coordinated international project, the Genome Atlas of Bamboo and Rattan (GABR), was launched in 2017. GABR achieved great success during Phase I (2017-2022). We will focus on investigating and protecting bamboo and rattan germplasm resources in Phase II ( 2022-2027). Here, we briefly review the achievements of Phase I and introduce the goals of Phase II.


Asunto(s)
Bosques , Desarrollo Sostenible , Humanos , Poaceae/genética
8.
Nanotechnology ; 22(40): 405201, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21896984

RESUMEN

Silicon based optoelectronic integration is restricted by its poor optoelectronic properties arising from the indirect band structure. Here, by combining silicon with another promising optoelectronic material, the CdS nanoribbon (NR), devices with heterojunction structure were constructed. The CdS NRs were also doped with gallium to improve their n-type conductivity. A host of nano-optoelectronic devices, including light emitting diodes, photovoltaic devices, and photodetectors, were successfully constructed on the basis of the CdS:Ga NR/Si heterojunctions. They all exhibited excellent device performances as regards high stability, high efficiency, and fast response speed. It is expected that the CdS NR/Si heterojunctions will have great potential for future applications of Si based optoelectronic integration.

9.
J Nanosci Nanotechnol ; 11(3): 2003-11, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21449340

RESUMEN

Single-crystal nitrogen doped CdS nanoribbons (NRs) with wurtzite structure were synthesized in ammonia atmosphere via a thermal evaporation deposition route. X-ray diffraction patterns reveal a significant contraction of the lattice constants due to the incorporation of nitrogen. Temperature-varied photoluminescence spectra of CdS:N NRs exhibit spectral features near the band edge, which can be ascribed to free excition and neutral acceptor-bound excition emissions. Electrical and photoelectrical properties of the CdS:N NRs were systemically studied by constructing the field-effect transistors based on individual NRs. The conductivity of the NRs can be tuned by two orders of magnitude by controlling the N doping concentration. Moreover, by post-annealing, the device performance is remarkably improved, in particular, the mobility of the CdS:N NRs is increased by nearly three orders of magnitude from approximately 10(-1) to hundreds of cm2/Vs. I(on)I(off) ratio of the annealed device reaches over 10(4). Photoconductive properties of the CdS:N NRs were also studied. The doped NRs show high sensitivity to the light with energy larger than band-gap and the response amplitude and speed depend on the doping concentration.


Asunto(s)
Compuestos de Cadmio/química , Mediciones Luminiscentes/instrumentación , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/instrumentación , Nitrógeno/química , Sulfuros/química , Transistores Electrónicos , Cristalización/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Ensayo de Materiales , Tamaño de la Partícula
10.
J Nanosci Nanotechnol ; 10(8): 5036-41, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21125847

RESUMEN

Spherical, octahedral, and cubic shaped PbSe quantum dots were successfully synthesized by virtue of a green chemical route, using environmentally friendly N,N-dimethyl-oleoyl amide as the solvent of Se. The process eliminates trioctylphoshine from the synthesis, using oleic acid as capping ligand in the noncoordinating solvent. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopic (EDS), were used to characterized the samples. The crystalline size can be tuned in a range from 8 nm to 16 nm by varing the reaction time or growth temperature. Based on the evidence of TEM images, the mechanism of PbSe quantum dots evolution from spherical to cubic structure has also been discussed. We found that the growth temperature played an important role in the morphology of PbSe quantum dots. This finding will enhance our understanding for the formation mechanism of nanomaterials with special shapes.

11.
Environ Sci Pollut Res Int ; 23(5): 4812-25, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26541148

RESUMEN

As the largest polycyclic aromatic hydrocarbons (PAHs) emission country, China is suffering from severe PAHs pollution. Twenty-eight lakes in the middle and lower reaches of the Yangtze River region (MLYR), where numerous lakes are located in and play very important roles in the development of the local economy and society, were selected to investigate the levels and sources of the PAHs in this region and the related influence factors. Concentrations of the 16 PAHs (∑PAHs) in the sediments ranged from 221.0 to 2418.8 ng g(-1) (dry weight). The mean ∑PAHs was higher in the lower reaches than in the middle reaches. ∑PAHs in the sediments was positively correlated with the local gross domestic product (GDP), which implies that GDP was the key factor to affect the PAHs level in the sediments of study area. According to the composition of 16 PAHs, the 28 lakes were grouped into 3 clusters. Major PAHs sources for the three types of lakes were significantly different, which were biomass combustion, coal combustion, and vehicle/coal source, respectively. The total toxic benzo(a)pyrene equivalent (TEQ(carc)) of the carcinogenic PAHs in the sediments varied from 12.9 to 472.9 ng TEQ(carc) g(-1). Benzo(a)pyrene (BaP) and dibenzo(a,h)anthracene (DaA) were the two main contributors to total TEQ(carc).


Asunto(s)
Sedimentos Geológicos , Lagos , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , China , Monitoreo del Ambiente , Medición de Riesgo , Ríos
12.
Chemosphere ; 119: 719-726, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25180823

RESUMEN

Effects of Cu(2+), Zn(2+), Cd(2+), and Ag(+) on the uptake of phenanthrene, pyrene, and benzo[a]pyrene by Microcystis aeruginosa were investigated. A biomimic passive sampler, triolein embedded cellulose acetate membrane (TECAM) was used to help to study the related mechanisms. The facilitation effects of the metals on the uptake of the PAHs by M. aeruginosa increased with the softness order of the metals (Zn(2+)≈Cd(2+)

Asunto(s)
Metales Pesados/toxicidad , Microcystis/efectos de los fármacos , Microcystis/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad , Benzo(a)pireno/metabolismo , Celulosa/análogos & derivados , Celulosa/química , Fenantrenos/metabolismo , Pirenos/metabolismo , Trioleína/química
13.
Int J Cardiol ; 83(2): 175-8, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12007692

RESUMEN

This study was to evaluate the clinical effects of percutaneous balloon angioplasty of Budd-Chiari syndrome (BCS) caused by inferior vena cava (IVC) obstruction. Between 1993 and 1999, 28 men and 14 women with mean age of 44+/-12 years underwent percutaneous balloon angioplasty for primary BCS. Color Doppler ultrasound and venography showed membranous and segmental obstruction of IVC in 29 and 13 patients, respectively. Fourteen patients also had left- and/or mid-hepatic vein obstruction. Angioplasty of IVC was successful in 41 patients (97.6%), resulting in a reduction of pressure gradient between IVC and the right atrium from 15.0+/-2.5 to 5.5+/-0.8 mmHg (P<0.01). A stent was placed in the site of obstruction in the patient with unsuccessful balloon angioplasty. Patients with successful angioplasty or stent placement had significant improvement in clinical symptoms indicated by a reduction in hepatomegaly and the degree of ascites. No specific attempt was made to treat the occluded left- and/or mid-hepatic vein due to the presence of potent right hepatic vein. Over the follow-up period of 32+/-12 months, restenosis of IVC occurred in only one patient (2.4%), which was redilated successfully. Percutaneous balloon angioplasty is a safe and effective therapy for Budd-Chiari syndrome caused by IVC obstruction, therefore should be the first choice of treatment for this condition.


Asunto(s)
Angioplastia de Balón/métodos , Síndrome de Budd-Chiari/terapia , Vena Cava Inferior , Trombosis de la Vena/terapia , Adolescente , Adulto , Análisis de Varianza , Síndrome de Budd-Chiari/diagnóstico , Niño , Constricción Patológica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Flebografía , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía Doppler , Grado de Desobstrucción Vascular , Trombosis de la Vena/diagnóstico
14.
J Colloid Interface Sci ; 354(1): 15-22, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21040929

RESUMEN

A low-cost, green, and reproducibly non-injection one-pot synthesis of high-quality CdS quantum dots (QDs) is reported. The synthesis was performed in the open air by mixing precursors cadmium stearate and S powder into a new solvent N-oleoylmorpholine. An overlapped nucleation-growth stage followed by a dominated growth stage was observed. The resulting QDs exhibited well-resolved absorption fine substructure and a dominant band-edge emission with a narrow size distribution (the full width at half maximum (fwhm) was only 22-24nm). The maximum photoluminescence (PL) quantum yield (QY) was as high as 46.5%. Highly monodispersed CdS QDs with tunable sizes and similar PL fwhm and QYs could also be obtained from the CdS QDs in a large-scale synthesis. The high-resolution transmission electron microscopy (HRTEM) images and powder X-ray diffraction (XRD) pattern suggested that the as-prepared QDs with high crystallinity had a cubic structure. A significant PL improvement and a continuous QY increase for the CdS QDs were observed during a long storage time in air and in a glovebox under room temperature. A slow surface reconstruction was proposed to be the cause for the PL enhancement of CdS QDs.


Asunto(s)
Compuestos de Cadmio/síntesis química , Puntos Cuánticos , Sulfuros/síntesis química , Compuestos de Cadmio/química , Técnicas de Laboratorio Clínico/economía , Luminiscencia , Sulfuros/química
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