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1.
Cancer Cell Int ; 23(1): 282, 2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-37981709

RESUMO

Hsa_circ_0022383 (circ_0022383) is a newly discovered circRNA. Its functions and relevant molecular mechanisms in tumorigenesis have not been reported. Here we aimed to explore how circ_0022383 regulates the tumorigenesis of non-small-cell lung cancer (NSCLC). We found thatcirc_0022383 expression was dramatically elevated in NSCLC tissues and cell lines. Upregulation of circ_0022383 was associated with poor prognosis in NSCLC patients. Silencing of circ_0022383 repressed cell proliferation and migration in vitro and inhibited oncogenesis and tumor metastasis in vivo. Moreover, our results discovered that circ_0022383 was mainly located in the cytoplasm of NSCLC cells. Mechanistically, circ_0022383 sponged miR-495-3p to modulate KPNA2 expression, thereby regulating NSCLC tumorigenesis and progression. In conclusion, our study demonstrates that circ_0022383 facilitates NSCLC tumorigenesis by regulating the miR-495-3p/KPNA2 axis, providing new insights into NSCLC development.

2.
Environ Pollut ; 338: 122653, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37778492

RESUMO

Forests are important sinks of atmospheric mercury. Quantifying mercury pools in forest ecosystem tissues are essential for understanding the global mercury cycle. To reveal the characteristics of Hg concentration and Hg pool distribution in natural forests at different ages, samples from the vegetation layer, organic horizons, coarse wood debris, and mineral soil layers were collected in young forest, middle forest, near-mature forest, and mature forest of Larix gmelinii forests at the Daxing'an Mountain. The results showed that there were differences in the absorption and accumulation of Hg by different tree species and tissues. In Larix gmelinii, the concentration of Hg followed the order of bark > branch > leaf > root > core, whereas in Betula platyphylla, the order was bark > leaf > branch > root > core. The mercury concentration in the organic horizons increased gradually with the decomposition process. There were no obvious regular patterns in the mercury concentrations of each tissue in different age groups Larix gmelinii forests. Furthermore, total biomass mercury pools (overstory, shrub layer, herb layer, moss layer, and coarse woody debris (CWD)) in the young, middle, near-mature, and mature forests of Larix gmelinii forests at Daxing'an Mountain were estimated to be 99.0 µg m-2,207 µg m-2,207 µg m-2 and 194 µg m-2, respectively. On ecosystem scale, total mercury pools were 16.9 mg m-2 (young), 27.5 mg m-2 (middle), 17.0 mg m-2 (near-mature), and 11.8 mg m-2(mature). The mineral soil mercury pool accounts for 94.0%-98.1% of the total ecosystem mercury pool, and its mercury pool proportion gradually decreased with the increase in forest age. These obtained results are quite valuable for further assessing the role of forest ecosystems in the atmospheric mercury cycle and estimating potential mercury emissions from biomass burning during forest wildfires.


Assuntos
Larix , Mercúrio , Ecossistema , Florestas , Árvores , Solo , Minerais , China
3.
Front Vet Sci ; 9: 1076906, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578437

RESUMO

The fermented feed has been used extensively as a growth promoter in agricultural animal production. However, the effects of fermented feed on swine gut microbiota are still largely unknown. The work presented here aimed to investigate the growth performance and gut microbiota of nursery pigs receiving the LPF diet (10% Lactobacillus plantarum and Pediococcus acidilactici co-fermented feed + basal diet) compared with pigs receiving the NC diet (basal diet). The data showed LPF diet numerically improved average daily gain and significantly increased fecal acetate, butyrate, and total short-chain fatty acid (SCFA) concentrations. Furthermore, gut microbiota structure and membership significantly changed in response to the addition of fermented feed in the diet. Gut microbiota results indicated that LPF treatment significantly enriched SCFA-producing bacteria such as Megasphaera, Roseburia, Faecalibacterium, Blautia, Selenomonas, Dialister, Acidaminococcus, Ruminococcus, and Bifidobacterium. Some of these bacteria also had anti-inflammatory and other beneficial functions. Overall, these findings suggested that Lactobacillus plantarum and Pediococcus acidilactici co-fermented feed benefited growth performance and established potential health impacts on the gut microbiota of nursery pigs.

4.
Front Plant Sci ; 13: 912916, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35720605

RESUMO

Of all forest biomes, boreal forests are experiencing the most significant warming. Drought caused by warming has a dramatic impact on species in boreal forests. However, little is known about whether the growth of trees and shrubs in boreal forests responds consistently to warming and drought. We obtained the tree-ring width data of 308 trees (Larix gmelinii and Pinus sylvestris var. mongolica) and 133 shrubs (Pinus pumila) from 26 sites in northeastern China. According to the climate data from 1950 to 2014, we determined three extreme drought years (1954, 1967, and 2008). The response difference of radial growth of trees and shrubs in boreal forests to drought was compared using resilience index, moving correlation and response analysis. The results showed that high temperature (mean and maximum temperature) in previous and current growing seasons promoted the growth of P. pumila, but inhibited the growth of trees. On the contrary, wetter conditions (higher PDSI) promoted tree growth but were not conducive to P. pumila growth in high latitudes. Moving correlation analysis showed similar results. In addition, water deficit was more likely to inhibit P. pumila growth in low latitudes. The drought resistance of P. pumila was stronger than that of L. gmelinii and P. sylvestris var. mongolica. Therefore, the growth loss and recovery time of P. pumila during drought was less than those of trees. We concluded that L. gmelinii and P. sylvestris var. mongolica are more prone to growth decline than P. pumila after the drought caused by climate warming. In the future climate warming, shrub growth may benefit more than trees. Our findings are of great significance in predicting the future changes in ecosystem composition and species distribution dynamics in extreme climate susceptible areas.

5.
Sci Total Environ ; 838(Pt 2): 156056, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35605849

RESUMO

Measurement and analysis of CO2 concentration at the ecosystem scale is the basis for studying ecosystem feedback to global climate change, and it is particularly useful for understanding the processes and mechanisms of ecosystem C exchange. Through observation of CO2 concentration at different heights, this study examined whether a CO2 lake phenomenon exists in the Larix gmelinii ecosystem of the Greater Khingan Mountains (China), and how it might be changed and what might represent its driving factors if such a phenomenon were found to exist. Plants and soils were sampled regularly to determine δ13C and to quantify the proportion of C released by each component of the ecosystem. The main path of C release and the main source of CO2 lake formation were investigated. Statistical analysis revealed that a CO2 lake phenomenon does exist in the L. gmelinii ecosystem. Comparative analysis showed that on the daily scale, when the ecosystem was a C source, the CO2 lake phenomenon often occurred. On the scale of the growing season, the strongest CO2 lake was accompanied by emergence of the peak respiratory flux. Stepwise regression analysis showed that environmental factors could explain 74.87% of the CO2 lake phenomenon. The occurrence and strength of the CO2 lakes were found to mainly respond to changes in temperature. Linear model analysis revealed that the rate of C release from autotrophic respiration in the forest was 51.18%; the rate of C release from heterotrophic respiration during litter decomposition was 51.78%. Therefore, the C release of the L. gmelinii ecosystem is mainly from autotrophic respiration. The CO2 released during decomposition of litter represented the main source for the formation of CO2 lakes. The CO2 lake effect has substantial impact on the net C flux and plays an important role in the C source/sink effect of the ecosystem.


Assuntos
Carbono , Ecossistema , Carbono/análise , Dióxido de Carbono/análise , China , Florestas , Estações do Ano
6.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3415-3427, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676702

RESUMO

Daxing'an Mountains is one of regions in China with the most significant climate change. Larix gmelinii and Pinus sylvestris var. mongolica are the most important species in this area. The study of their radial growth response to climate change would provide a scientific basis for predicting the dynamics of boreal forests under climate change. A total of 451 tree-ring cores of L. gmelinii and P. sylvestris var. mongolica were collected from six sites in the Daxing'an region, and 12 standard chronologies were established. We compared the tree growth trend since 1900, and analyzed their response to the climate factor in each site using Pearson correlation analysis. Effects of temperature and precipitation on the annual radial growth of L. gmelinii and P. sylvestris var. mongolica were investigated by linear mixed models. The time stability of the relationship between two species growth-climate was compared by moving correlation. The results showed that the radial growth of L. gmelinii was negatively correlated with mean temperature in March and positively correlated with precipitation in the previous winter and July of current year. The radial growth of P. sylvestris var. mongolica was positively correlated with temperature in August and precipitation in the growing season (from May to September) of current year. Snow in winter played an important role in promoting the radial growth of L. gmelinii, whereas precipitation in summer limited the radial growth of P. sylvestris var. mongolica. The responses of L. gmelinii and P. sylvestris var. mongolica to climate change were significantly different, which affected tree growth, species composition, and spatial distribution in the boreal forests.


Assuntos
Larix , Pinus sylvestris , China , Mudança Climática , Árvores
7.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2316-2324, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313048

RESUMO

Understanding the emission factors of fine particulate matter (PM2.5) released by forest fuel combustion is important for revealing the impacts of forest fire on atmosphere and ecosystem. Water-soluble ions are important components of fine particulate matter, with great significance to the formation of particulate matter. A self-designed biomass combustion system was used to simulate the combustion of three components (trunks, branches, barks) and their surface dead fuel (litter, semi-humus, humus) of five tree species (Quercus mongolica, Betula platyphylla, Larix gmelinii, Betula dahurica, Populus davidiana) and branches of three shrub species (Corylus heterophylla, Lespedeza bicolor, Rhododendron dauricum) in Great Xing'an Mountains in Inner Mongolia. The water-soluble ion emission factors (Na+, NH4+, K+, Mg2+, Ca2+, F-, Cl-, NO3-, NO2-, SO42-) in PM2.5 under two combustion conditions (smoldering and flaming) were measured by ISC1100 ion chromatograph. The results showed that for the water-soluble ion detected in PM2.5 from combustion of all types of materials, K+, Cl- and Na+ were the main components in smoldering, while K+, Cl- and SO42- were the main components in flaming. There was significant difference in the total amount of water-soluble ions in PM2.5 from the same type of material under different combustion conditions. During the smoldering period, the emission factor of water-soluble inorganic ions in PM2.5 of shrub branches was higher than that of flaming. The cation to anion ratio in PM2.5 was 1.26 for all trees, 1.12 for surface dead fuel of trees, and 2.0 for branch of shrub, indicating that the particulate matter was alkaline. Forest fires in Great Xing'an Mountains could not result in ecosystem acidification by releasing water-soluble ions.


Assuntos
Poluentes Atmosféricos , Água , Poluentes Atmosféricos/análise , China , Ecossistema , Florestas , Íons/análise , Material Particulado/análise
8.
Pest Manag Sci ; 77(6): 2737-2746, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33527628

RESUMO

BACKGROUND: Carboxyl/cholinesterases (CCEs) are thought to play a pivotal role in the degradation of sex pheromones and plant-derived odorants in insects, but their exact biochemistry and physiological functions remain unclear. RESULTS: In this study, two paralogous antennae-enriched CCEs from Plutella xylostella (PxylCCE16a and 16c) were identified and functionally characterized. High-purity protein preparations of active recombinant PxylCCE16a and 16c have been obtained from Sf9 insect cells by Ni2+ affinity purification. Our results revealed that the purified recombinant PxylCCE016c is able to degrade two sex pheromone components Z9-14:Ac and Z11-16:Ac at 27.64 ± 0.79% and 24.40 ± 3.07%, respectively, while PxylCCE016a presented relatively lower activity. Additionally, a similar difference in activity was measured in plant-derived odorants. Furthermore, both CCEs displayed obvious preferences for the two sex pheromone components, especially on Z11-16:Ac (Km values are in the range 7.82-45.06 µmol L-1 ) which much lower than plant odorants (Km values are in the range 1290-4030 µmol L-1 ). Furthermore, the activity of the two newly identified CCEs is pH-dependent. The activity at pH 6.5 is obviously higher than that at pH 5.0. Interestingly, only PxylCCE016c can be inhibited by a common esterase inhibitor triphenyl phosphate (TPP) with LC50 of 1570 ± 520 µmol L-1 . CONCLUSION: PxylCCE16c plays a more essential role in odorant degradation than PxylCCE16a. Moreover, the current study provides novel potential pesticide targets for the notorious moth Plutella xylostella. © 2021 Society of Chemical Industry.


Assuntos
Mariposas , Atrativos Sexuais , Animais , Carboxilesterase/genética , Proteínas de Insetos/genética , Mariposas/genética , Odorantes , Feromônios , Plantas , Atrativos Sexuais/farmacologia
9.
Sci Total Environ ; 727: 138558, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32498208

RESUMO

Stable isotopes in wood lignin methoxyl groups (δ2HLM and δ13CLM values) have been suggested as valuable complementary paleoclimate proxies. In permafrost forests, tree growth is influenced by multiple factors, however temperature appears to have the strongest impact on tree growth and, therefore, on carbon cycling. To test whether δ2HLM and δ13CLM values of trees from permafrost regions might record climate parameters, two dominant tree species (Larix gmelinii, larch, and Pinus sylvestris var. mongolica, pine) collected from a permafrost forest in China's Greater Hinggan Mountains, were investigated. The two tree species larch and pine covered time spans of 1940 to 2013 and 1870 to 2013, respectively. Results showed significant correlations of pine and larch δ2HLM values and larch δ13CLM values with temperatures and in particular with the mean temperature of the growing season from April to August. However, only weak correlations of δ2HLM and δ13CLM values with moisture conditions, such as precipitation amount and relative humidity were observed. In addition, species specificity in the climate response was most obvious for δ13CLM values. Compared to a temperature reconstruction based on tree ring width, pine δ2HLM-based reconstruction showed strongest spatial correlations with regional temperature. Therefore, δ2HLM values might be a promising proxy to reconstruct growing-season temperatures in permafrost regions.


Assuntos
Pergelissolo , China , Florestas , Lignina , Temperatura , Árvores , Madeira
10.
Tree Physiol ; 39(1): 88-103, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29920609

RESUMO

Tree-ring δ13C and δ18O of dominant Dahurian larch and Mongolia pine in the permafrost region of the northern Great Higgnan Mountains, China were used to elucidate species-specific ecophysiological responses to warming temperatures and increasing CO2 over the past century. Larch and pine stable carbon discrimination (Δ13C) 13C and δ18O in tree rings both showed synchronous changes during the investigated period (1901-2010), but with species-specific isotopic responses to atmospheric enriched CO2 and warming. Tree-ring Δ13C and δ18O were controlled by both maximum temperature and moisture conditions (precipitation, relative humidity and vapor pressure deficit), but with different growth periods (Δ13C in June-July and δ18O in July-August, respectively). In addition, stable isotopes of larch showed relatively greater sensitivity to moisture deficits than pine. Climatic conditions from 1920 to 1960 strongly and coherently regulated tree-ring Δ13C and δ18O through stomatal conductance. However, climatic-sensitivities of tree-ring Δ13C and δ18O recently diverged, implying substantial adjustments of stomatal conductance, photosynthetic rate and altered water sources over recent decades, which reveal the varied impacts of each factor on tree-ring Δ13C and δ18O over time. Based on expected changes in leaf gas-exchange, we isolated the impacts of atmospheric CO2 and climate change on intrinsic water-use efficiency (iWUE) over the past century. Higher intracellular CO2 in pine than larch from 1960 onwards suggests this species may be more resilient to severe droughts in the future. Our data also illustrated no weakening of the iWUE response to increasing CO2 in trees from this permafrost region. The overall pattern of CO2 enrichment and climate impacts on iWUE of pine and larch were similar, but warming increased iWUE of larch to a greater extent than that of pine over recent two decades. Taken together, our findings highlight the importance of considering how leaf gas-exchange responses to atmospheric CO2 concentration influence species-specific responses to climate and the alteration of the hydrological environment in forests growing in regions historically dominated by permafrost that will be changing rapidly in response to future warming and increased CO2.


Assuntos
Dióxido de Carbono/metabolismo , Aquecimento Global , Larix/fisiologia , Pergelissolo , Pinus/fisiologia , Árvores/fisiologia , China , Água/metabolismo
11.
Genome Announc ; 2(6)2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25540334

RESUMO

Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated disease (PCVAD). Here, we report the complete genome sequence of PCV2 strain HB-MC1, which belongs to PCV2d.

12.
Ying Yong Sheng Tai Xue Bao ; 23(8): 2149-56, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23189692

RESUMO

By using static chamber-gas chromatograph technique, an in situ measurement was conducted on the soil CH4, CO2, and N2O fluxes in a cold-temperate Larix gmelinii forest in Inner Mongolia from June to September 2007, aimed to understand the diurnal and seasonal variations of soil greenhouse gasses fluxes and their relations with the associated environmental factors in L. gmelinii forests in cold-temperate zone. In growth season, the soil in the L. gmelinii forest was the sink of atmospheric CH4, with the flux ranged from 22.3 to 107.8 microg CH4-C x m(-2) x h(-1). The mean monthly uptake of CH4 in June, July, August, and September was 34.0 +/- 7.1, 71.4 +/- 9.4, 86.3 +/- 7.9, and 40.7 +/- 6.2 microg x m(-2) x h(-1), respectively. The mean diurnal flux of soil CH4 from June to September showed the same variation trend, i. e., peaked at 10:00 am. The diurnal variation of soil CO2 flux showed an obvious double-peak, and the mean monthly CO2 flux was in the order of July > August > June > September. Soil N2O flux varied dramatically from -9.1 to 31.7 microg x m(-2) x h(-1). Soil temperature and humidity were the main factors affecting the CH4 and CO2 fluxes, and soil temperature mainly affected the N2O flux. In the L. gmelinii forest, the CH4, CO2, and N2O fluxes measured at 10:00 am could represent the diurnal CH4, CO2, and N2O fluxes on the same day.


Assuntos
Ecossistema , Monitoramento Ambiental , Larix/crescimento & desenvolvimento , Solo/química , Dióxido de Carbono/análise , China , Metano/análise , Óxido Nitroso/análise , Estações do Ano , Temperatura
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