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1.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1729-1736, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694455

RESUMEN

The process of plant water use is complex and changeable, which is affected by various factors. Exploring the sources and influencing factors of plant water use can provide reference for clarifying the mechanisms of forest water adaptation under climate change. We chosen the typical forest communities in the hilly region of Sou-thern China, Pinus massoniana and Quercus acutissima mixed forest as the research object. By analyzing water sources of plants in different seasons, the factors affecting the changes of water sources were explored in combination with soil water, precipitation, and plant roots. The results showed that water use characteristics of P. massoniana and Q. acutissima were similar and both mainly utilized 0-40 cm soil water during the dry season, with proportions of 60.0% and 66.6%. During the rainy season, as soil water content of deep layers increased, the main water sources of both gradually shifted towards deep soil. The similarity proportion indices of P. massoniana and Q. acutissima were above 60%, indicating that there was an obvious water competition between them. Root system of Q. acutissima had plasticity in water absorption, and played a dominant role in absorbing shallow water during the dry season. Water was the main driving factor for water source transformation of Q. acutissima and P. massoniana during the rainy season. Compared with P. massoniana, Q. acutissima was more sensitive to the changes of water sources. Under the background of future warming and drying, the competition between the two species for shallow water sources might be intensified. Those two species should be sparsely planted or thinned to optimize forest structure to cope with water stress.


Asunto(s)
Pinus , Quercus , Aclimatación , China , Suelo
2.
Ying Yong Sheng Tai Xue Bao ; 32(4): 1424-1432, 2021 Apr.
Artículo en Chino | MEDLINE | ID: mdl-33899411

RESUMEN

Given the facts that urban land is extremely limited and ecological environment protection is confronted with severe challenges, it is of great importance to effectively construct green infrastructure (GI) network and identify relatively important landscape ecological components. We identified and prioritized GI network centers in Fuzhou downtown area using the MSPA and the landscape connectivity evaluation. The least cost path method and gravity model were used to construct the potential corridors at multiple levels. The density analysis and blind area analysis were used to extract and prioritize the GI nodes and to obtain the optimized GI network. The results showed that the first-level GI network centers were mainly distributed in the north and south of Fuzhou downtown, while those in the central region were small and scattered. The comprehensive resistance of landscape was low in the periphery but high in the middle, with poor integral connectivity. The GI corridor system with existing corridors and potential corridors was employed to enhance the connectivity among network centers. Furthermore, the GI nodes were extracted to provide a "transfer station" for material circulation and energy flow, which could partly solve the problems including excessive substrate resistance and the long connection corridor in some areas. The spatial prioritization of GI elements could make the construction of GI network more scientific and also provide reference for the future planning period and construction timing of GI network in Fuzhou.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China
3.
Front Genet ; 10: 1040, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31708972

RESUMEN

Pre-implantation development is a dynamic, complex and precisely regulated process that is critical for mammalian development. There is currently no description of the role of the long noncoding RNAs (lncRNAs) during the pre-implantation stages in the goat. The in vivo transcriptomes of oocytes (n = 3) and pre-implantation stages (n=19) at seven developmental stages in the goat were analyzed by RNA sequencing (RNA-Seq). The major zygotic gene activation (ZGA) event was found to occur between the 8- and 16-cell stages in the pre-implantation stages. We identified 5,160 differentially expressed lncRNAs (DELs) in developmental stage comparisons and functional analyses of the major and minor ZGAs. Fourteen lncRNA modules were found corresponding to specific pre-implantation developmental stages by weighted gene co-expression network analysis (WGCNA). A comprehensive analysis of the lncRNAs at each developmental transition of high correlation modules was done. We also identified lncRNA-mRNA networks and hub-lncRNAs for the high correlation modules at each stage. The extensive association of lncRNA target genes with other embryonic genes suggests an important regulatory role for lncRNAs in embryonic development. These data will facilitate further exploration of the role of lncRNAs in the developmental transformation in the pre-implantation stage.

4.
Water Res ; 142: 354-362, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29908463

RESUMEN

Tetrabromobisphenol A (TBBPA) has attracted considerable attention due to its ubiquitous presence in different environmental compartments worldwide. However, information on its aerobic biodegradability in coastal environments remains unknown. Here, the aerobic biodegradation of TBBPA using a Pseudoalteromonas species commonly found in the marine environment was investigated. We found that extracellular biogenic siderophore, superoxide anion radical (O2•-), hydrogen peroxide (H2O2), and hydroxyl radical (•OH) were involved in TBBPA degradation. Upregulation of genes (nqrA and lodA) encoding Na+-translocating NADH-quinone oxidoreductase and l-lysine-ε-oxidase supported the extracellular O2•- and H2O2 production. The underlying mechanism of TBBPA biodegradation presumably involves both O2•- reduction and •OH-based advanced oxidation process (AOP). Furthermore, TBBPA intermediates of tribromobisphenol A, 4-isopropylene-2,6-dibromophenol, 4-(2-hydroxyisopropyl)-2,6-dibromophenol, 2,4,6-tribromophenol (TBP), 4-hydroxybenzoic acid, and 2-bromobenzoic acid were detected in the culture medium. Debromination and ß-scission pathways of TBBPA biodegradation were proposed. Additionally, membrane integrity assays revealed that the increase of intracellular catalase (CAT) activity and the extracellular polymeric substances (EPS) might account for the alleviation of oxidative damage. These findings could deepen understanding of the biodegradation mechanism of TBBPA and other related organic pollutants in coastal and artificial bioremediation systems.


Asunto(s)
Bifenilos Polibrominados/química , Pseudoalteromonas/metabolismo , Especies Reactivas de Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo , Contaminantes Químicos del Agua/química , Biodegradación Ambiental , Oxidación-Reducción
5.
Sci Rep ; 8(1): 3909, 2018 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-29500394

RESUMEN

This study found that miR-27 is expressed in muscle and regulates muscle proliferation and differentiation. We explored the function and regulatory mechanism of miR-27b in goat muscle proliferation and differentiation. Compared with the Boer goat, higher expression of miR-27b was observed in all of the collected muscle tissues of Anhuai goat, excluding the kidney, whereas the opposite expression pattern was observed for Pax3, which showed lower expression in Anhuai goat. Expression of miR-27b decreased gradually during the proliferation of skeletal muscle satellite cells in Anhuai goat and increased during differentiation; however, the expression pattern of Pax3 was opposite. The regulatory activity of miR-27b demonstrated that miR-27b inhibited the proliferation of skeletal muscle satellite cells, but promoted their differentiation. Moreover, function research demonstrated that Pax3 negatively regulated myogenic differentiation of goat skeletal muscle satellite cells, but accelerated their proliferation. The results of a dual-luciferase reporter analysis showed that miR-27b directly targeted the 3'-untranslated regions of Pax3 mRNA, and western blot and immunofluorescence staining analyses showed that miR-27b inhibited expression of the Pax3 protein. In goats, miR-27b can regulate myogenic proliferation and differentiation by targeting Pax3.


Asunto(s)
Diferenciación Celular , Proliferación Celular , Regulación del Desarrollo de la Expresión Génica , MicroARNs/genética , Desarrollo de Músculos , Factor de Transcripción PAX3/metabolismo , Células Satélite del Músculo Esquelético/citología , Animales , Células Cultivadas , Femenino , Cabras , Factor de Transcripción PAX3/genética , Células Satélite del Músculo Esquelético/metabolismo
6.
Neurol Res ; 40(6): 433-444, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29600891

RESUMEN

Background Normobaric oxygen (NBO) has received considerable attention due to controversial data in brain protection in patients with acute stroke. This study aims to analyze current data of NBO on brain protection as used in the clinic. Methods We searched for and reviewed relevant articles and references from Pubmed, Medline, Embase, Cochrane, and Clincialtrials.gov that were published prior to October 2017. Data from prospective studies were processed using RevMan5.0 software, provided by Cochrane collaboration and transformed using relevant formulas. Results A total of 11 prospective RCT studies including 6366 patients with acute stroke (NBO group, 3207; control group, 3159) were enrolled in this analysis. △NIHSS represented the values of NIHSS at 4, 24 h, or 7 days post-stroke minus baseline NIHSS. Compared to controls, there was a minor trend toward NBO benefits in short-term prognostic indices, as indicated by decreased ΔNIHSS at our defined time points. By contrast, NBO decreased Barthel Index scores between 3 and 7 months, and increased death rates at 3, 6 months, and 1 year, whereas, modified Rankin Scale scores between 3 and 6 months were unchanged. Conclusions The existing trends toward benefits revealed in this meta-analysis help us appreciate the promising value of NBO, although current evidence of NBO on improving clinical outcomes of stroke is insufficient. Well-designed multi-center clinical trials are encouraged and urgently needed to further explore the efficacy of NBO on brain protection.


Asunto(s)
Oxígeno/uso terapéutico , Accidente Cerebrovascular/terapia , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Opt Express ; 23(10): 13499-504, 2015 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-26074597

RESUMEN

We experimentally demonstrate an end-to-end ultra-broadband cloud-DSL network using passive optical network (PON) based fronthaul with electronic code-division-multiple-access (eCDMA) encoding and decoding. Forty-eight signals that are compliant with the very-high-bit-rate digital subscriber line 2 (VDSL2) standard are transmitted with a record throughput of 5.76 Gb/s over a hybrid link consisting of a 20-km standard single-mode fiber and a 100-m twisted pair.

8.
Neurotherapeutics ; 12(3): 667-77, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25956401

RESUMEN

UNLABELLED: Symptomatic intracranial arterial stenosis (SIAS) is very common in octo- and nonagenarians, especially in the Chinese population, and is likely the most common cause of stroke recurrence worldwide. Clinical trials demonstrate that endovascular treatment, such as stenting, may not be suitable for octogenarians with systemic diseases. Hence, less invasive methods for the octogenarian patients are urgently needed. Our previous study (unique identifier: NCT01321749) showed that repetitive bilateral arm ischemic preconditioning (BAIPC) reduced the incidence of stroke recurrence by improving cerebral perfusion (confirmed by single photon emission computed tomography and transcranial Doppler sonography) in patients younger than 80 years of age; however, the safety and effectiveness of BAIPC on stroke prevention in octo- and nonagenarians with SIAS are still unclear. The objective of this study was to evaluate the safety and effectiveness of BAIPC in reducing stroke recurrence in octo- and nonagenarian patients with SIAS. Fifty-eight patients with SIAS were enrolled in this randomized controlled prospective study for 180 consecutive days. All patients enrolled in the study received standard medical management. Patients in the BAIPC group (n = 30) underwent 5 cycles consisting of bilateral arm ischemia followed by reperfusion for 5 min each twice daily. Those in the control group (n = 28) underwent sham-BAIPC twice daily. Blood pressure, heart rate, local skin status, plasma myoglobin, and plasma levels of thrombotic and inflammatory markers were documented in both groups before beginning the study and for the first 30 days. Finally, the incidences of stroke recurrence and magnetic resonance imaging during the 180 days of treatment were compared. Compared with the control, BAIPC had no adverse effects on blood pressure, heart rate, local skin integrity, or plasma myoglobin, and did not induce cerebral hemorrhage in the studied cohort. BAIPC reduced plasma high sensitive C-reactive protein, interleukin-6, plasminogen activator inhibitor-1, leukocyte count, and platelet aggregation rate and elevated plasma tissue plasminogen activator (all p < 0.01). In 180 days, 2 infarctions and 7 transient ischemic attacks were observed in the BAIPC group compared with 8 infarctions and 11 transient ischemic attacks in the sham BAIPC group (p < 0.05). BAIPC may safely inhibit stroke recurrence, protect against brain ischemia, and ameliorate plasma biomarkers of inflammation and coagulation in octo- and nonagenarians with SIAS. A multicenter trial is ongoing. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov, unique identifier: NCT01570231.


Asunto(s)
Brazo/irrigación sanguínea , Precondicionamiento Isquémico/métodos , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/terapia , Anciano de 80 o más Años , Presión Sanguínea , Femenino , Frecuencia Cardíaca , Humanos , Inflamación/sangre , Precondicionamiento Isquémico/efectos adversos , Masculino , Músculos/patología , Estudios Prospectivos , Piel/patología , Resultado del Tratamiento
9.
Environ Sci Technol ; 48(21): 12876-85, 2014 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-25296002

RESUMEN

Cr(VI) biotreatment has attracted a substantial amount of interest due to its cost effectiveness and environmental friendliness. However, the slow Cr(VI) bioreduction rate and the formed organo-Cr(III) in solution are bottlenecks for biotechnology application. In this study, a novel strain, Acinetobacter sp. HK-1, capable of reducing Cr(VI) and immobilizing Cr(III) was isolated. Under optimal conditions, the Cr(VI) reduction rate could reach 3.82 mg h(-1) g cell(-1). To improve the Cr(VI) reduction rate, two quinone/graphene oxide composites (Q-GOs) were first prepared via a one-step covalent chemical reaction. The results showed that 2-amino-3-chloro-1,4-naphthoquinone-GO (NQ-GO) exhibited a better catalytic performance in Cr(VI) reduction compared to 2-aminoanthraquinone-GO. Specifically, in the presence of 50 mg L(-1) NQ-GO, a Cr(VI) removal rate of 190 mg h(-1) g cell(-1), which was the highest rate obtained, was achieved. The increased Cr(VI) reduction rate is mainly the result of NQ-GO significantly increasing the Cr(VI) reduction activity of cell membrane proteins containing dominant Cr(VI) reductases. X-ray photoelectron spectroscopy analysis found that Cr(VI) was reduced to insoluble Cr(III), which was immobilized by glycolipids secreted by strain HK-1. These findings indicate that the application of strain HK-1 and NQ-GO is a promising strategy for enhancing the treatment of Cr(VI)-containing wastewater.


Asunto(s)
Acinetobacter/metabolismo , Cromo/metabolismo , Grafito/metabolismo , Quinonas/metabolismo , Acinetobacter/aislamiento & purificación , Biodegradación Ambiental , Electrones , Glucosa/análisis , Concentración de Iones de Hidrógeno , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
10.
Sci China Life Sci ; 53(1): 87-93, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20596959

RESUMEN

This study aimed to investigate the effects of arsenic trioxide (As(2)O(3)) on the mitochondrial DNA (mtDNA) of acute promyelocytic leukemia (APL) cells. The NB4 cell line was treated with 2.0 micromol/L As(2)O(3) in vitro, and the primary APL cells were treated with 2.0 micromol/L As(2)O(3) in vitro and 0.16 mg kg(-1) d(-1) As(2)O(3) in vivo. The mitochondrial DNA of all the cells above was amplified by PCR, directly sequenced and analyzed by Sequence Navigatore and Factura software. The apoptosis rates were assayed by flow cytometry. Mitochondrial DNA mutation in the D-loop region was found in NB4 and APL cells before As(2)O(3) use, but the mutation spots were remarkably increased after As(2)O(3) treatment, which was positively correlated to the rates of cellular apoptosis, the correlation coefficient: r (NB4-As2O3)=0.973818, and r (APL-As2O3)=0.934703. The mutation types include transition, transversion, codon insertion or deletion, and the mutation spots in all samples were not constant and regular. It is revealed that As(2)O(3) aggravates mtDNA mutation in the D-loop region of acute promyelocytic leukemia cells both in vitro and in vivo. Mitochondrial DNA might be one of the targets of As(2)O(3) in APL treatment.


Asunto(s)
Apoptosis/efectos de los fármacos , Arsenicales/farmacología , ADN Mitocondrial/genética , Mutación/efectos de los fármacos , Óxidos/farmacología , Antineoplásicos/farmacología , Trióxido de Arsénico , Secuencia de Bases , Línea Celular Tumoral , Análisis Mutacional de ADN , Humanos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patología , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Células Tumorales Cultivadas
11.
Protein Sci ; 11(12): 2947-57, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12441392

RESUMEN

H-N-H is a motif found in the nuclease domain of a subfamily of bacteria toxins, including colicin E7, that are capable of cleaving DNA nonspecifically. This H-N-H motif has also been identified in a subfamily of homing endonucleases, which cleave DNA site specifically. To better understand the role of metal ions in the H-N-H motif during DNA hydrolysis, we crystallized the nuclease domain of colicin E7 (nuclease-ColE7) in complex with its inhibitor Im7 in two different crystal forms, and we resolved the structures of EDTA-treated, Zn(2+)-bound and Mn(2+)-bound complexes in the presence of phosphate ions at resolutions of 2.6 A to 2.0 A. This study offers the first determination of the structure of a metal-free and substrate-free enzyme in the H-N-H family. The H-N-H motif contains two antiparallel beta-strands linked to a C-terminal alpha-helix, with a divalent metal ion located in the center. Here we show that the metal-binding sites in the center of the H-N-H motif, for the EDTA-treated and Mg(2+)-soaked complex crystals, were occupied by water molecules, indicating that an alkaline earth metal ion does not reside in the same position as a transition metal ion in the H-N-H motif. However, a Zn(2+) or Mn(2+) ions were observed in the center of the H-N-H motif in cases of Zn(2+) or Mn(2+)-soaked crystals, as confirmed in anomalous difference maps. A phosphate ion was found to bridge between the divalent transition metal ion and His545. Based on these structures and structural comparisons with other nucleases, we suggest a functional role for the divalent transition metal ion in the H-N-H motif in stabilizing the phosphoanion in the transition state during hydrolysis.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Cationes Bivalentes/metabolismo , Colicinas , Desoxirribonucleasas/química , Desoxirribonucleasas/metabolismo , Metales/metabolismo , Fosfatos/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sitios de Unión , ADN/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Estructura Terciaria de Proteína , Difracción de Rayos X
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