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1.
Sci Total Environ ; 916: 170098, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38278250

RESUMO

Soil moisture (SM) directly controls the land surface energy partition which plays an important role in the formation of extreme weather events. However, its dependence on specific climatic conditions is not thoroughly understood due to the complexity of soil moisture effects. Here, we examine the relationship between SM and surface energy partitioning under different climate conditions, and identify the influence paradigms of soil moisture on surface energy partition. We find that temperature changes can explicitly determine the impact paradigm of different physical processes, i.e. evapotranspiration, soil freezing and thawing, and such influence paradigms are also affected by atmospheric aridity (VPD). Globally, there are five paradigms that effects on surface energy partitioning, including the warm-wet paradigm (WW), transitional paradigm (TP), warm-dry paradigm (WD), cool-wet paradigm (CW) and cold paradigm (CP). Since 1981, the global area proportion for TP is observed to increase pronouncedly. We also find that the critical SM threshold exhibits regional variations and the global average is 0.45 m3/m3. The identified paradigms and their long-term change trends provide new insights into the global intensification of land-atmosphere interaction, which has important implications for global warming and the formation of heatwaves.

2.
iScience ; 26(6): 106837, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37250783

RESUMO

Soil moisture (SM) and atmospheric humidity (AH) are crucial climatic variables that significantly affect the climate system. However, the combined influencing mechanisms of SM and AH on the land surface temperature (LST) under global warming are still unclear. Here, we systematically analyzed the interrelationships among annual mean values of SM, AH, and LST using ERA5-Land reanalysis data and revealed the role of SM and AH on the spatiotemporal variations of LST through mechanism analysis and regression methods. The results showed that net radiation, SM, and AH could well model the long-term variability of LST well and explain 92% of the variability. Moreover, SM played an essential and different role under the different LST backgrounds. The AH always displayed a greenhouse effect on the LST. This study provides essential insights into the global climate change mechanism from the surface hydrothermal processes perspective.

3.
PLoS One ; 17(12): e0278574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36469532

RESUMO

The objective of this study was to assess the quantitative diagnostic value of T2 relaxation time for determining liver iron grades in the presence of fat and fibrosis. Sixty Sprague-Dawley (SD) male rats were randomly divided into control (10 rats) and model (50 rats) groups. The model group of coexisting iron, steatosis, and liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride (CCl4) dissolved in edible vegetable oil (40% v/v). The control group received an intraperitoneal injection of 0.9% saline. All rats underwent multi-echo gradient and spin echo (M-GRASE) magnetic resonance imaging, and the T2 relaxation time of the liver was measured. The rats were killed immediately after imaging, and liver specimens were extracted for histological evaluation of steatosis, iron, and fibrosis. The relationship and differences between T2 relaxation time and liver fibrosis stage, as well as the pathological grade of hepatic steatosis, were assessed by Spearman's rank correlation coefficient, non-parametric Mann-Whitney test, and the Kruskal-Wallis test. The area under the receiver operating characteristic curve and interaction analysis were used to quantify the diagnostic performance of T2 relaxation time for detecting different degrees of liver iron grades. Six normal control rats and 34 model rats were included in this study. Fibrosis stages were F0 (n = 6), F1 (n = 6), F2 (n = 8), F3 (n = 10), and F4 (n = 10). Steatosis grades were S0 (n = 5), S1 (n = 8), S2 (n = 12), and S3 (n = 15). Hepatocyte or Kupffer cell iron grades were 0 (n = 7), 1 (n = 9), 2 (n = 12), 3 (n = 10), and 4 (n = 2). The liver fibrosis stages were positively correlated with the iron grades (P < 0.01), and the iron grades and fibrosis stages were negatively correlated with the T2 relaxation time (P < 0.01). The T2 relaxation times exhibited strongly significant differences among rats with different histologically determined iron grades (P < 0.01). Pairwise comparisons between each grade of liver iron indicated significant differences between all iron grades, except between grades 0 and 1, and between grades 1 and 2 (P > 0.05). The T2 relaxation time of the liver had an area under the receiving operating characteristic curve (AUC) of 0.965 (95% CI 0.908-0.100, P < 0.001) for distinguishing rats with a pathological grade of hepatic iron (grade ≥ 1) from those without, an AUC of 0.871 (95% CI 0.757-0.985, P < 0.001) for distinguishing rats with no iron overload (grade ≤ 1) from rats with moderate or severe iron overload (grade ≥ 2), and an AUC of 0.939 (95% CI 0.865-1.000, P < 0.001) for distinguishing rats with no to moderate iron overload (grade ≤ 2) from rats with severe iron overload (grade 3). The interaction of different pathological grades of iron, steatosis, and fibrosis has a negligible influence on the T2 relaxation time (P > 0.05). In conclusion, T2 relaxation time can assess histologically determined liver iron grades, regardless of coexisting liver steatosis or fibrosis; therefore, it is suitable for distinguishing between the presence and absence of iron deposition and it is more accurate for higher iron grading.


Assuntos
Fígado Gorduroso , Fígado , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Fígado Gorduroso/patologia , Imageamento por Ressonância Magnética/métodos , Fibrose
4.
Sci Total Environ ; 850: 158013, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970467

RESUMO

Potato production plays an important role in safeguarding food security in China since the central government implemented the 'Potato-as-Staple-Food' policy in 2015. However, a key challenge facing China's potato production is to realize a tradeoff between economic return and environmental impact. Effective strategies for reducing carbon emission without compromising potato yield remain to be developed. This study conducted a comprehensive assessment by integrating climate, soil, crop, and agricultural input data, crop model and life cycle impact assessment model to quantify potato yields, GHG emission amounts and intensities (GHGI), and economic benefits under the conventional planting pattern (CPP), the lowest GHG emission pattern (LEP), and the highest yield pattern (HYP) across China's potato planting regions including four sub-regions, i.e., North Single planting region (NS), Central Double planting region (CD), South Winter planting region (SW), and Southwest Mixed planting region (SWM). Averaged fresh potato yield, GHG emission amount, and GHGI under the CPP were 21.7 t ha-1, 2815.1 kg CO2eq ha-1, and 137.3 kg CO2eq t-1, respectively, in China's potato planting region. Compared with the CPP, averaged GHG emission amount and GHGI under the LEP could be decreased by 48.2 % and 51.5 % respectively while the fresh potato yield and economic benefit could be enhanced by 8.1 % and 18.5 %, respectively. For the HYP, averaged GHG emission amount and GHGI could be decreased by 24.2 % and 39.8 % respectively while the fresh potato yield and economic benefit could be enhanced by 18.7 % and 39.6 %, respectively, compared with the CPP. Across the four potato planting regions, SW had the largest potential in reducing GHG emissions owing to a high reduction amount of nitrogen application rate. Our study demonstrates that optimizing agronomic management could reduce environmental impact without compromising economic benefit and provides a scientific method for assessing crop potential to realize the climate-smart planting.


Assuntos
Solanum tuberosum , Agricultura/métodos , Carbono , China , Fertilizantes , Nitrogênio , Solo
5.
Sci Total Environ ; 847: 157662, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35907552

RESUMO

Excessive urban temperature exerts a substantially negative impact on urban sustainability. Three-dimensional (3D) landscapes have a great impact on urban thermal environments, while their heat conditions and driving factors still remain unclear. This study mapped urban 3D neighborhoods and their associated SUHI (surface urban heat island) intensities in summer daytime across 57 Chinese cities, and then explored their relationships, driving factors as well as implications. Nine categories of urban 3D neighborhoods existed in Chinese cities and the 3D neighborhood of High Density & Medium Rise (HDMR) contributed the largest share of urban areas. The distribution of 3D neighborhoods varied among cities due to their distinct natural and economic traits. The average SUHI intensity can amount to 4.27 °C across all Chinese 3D neighborhoods. High Density & Low Rise (HDLR) and HDMR presented higher SUHI intensities than other 3D neighborhoods in China. Urban green space (UGI) and building height (BH) had great influences on SUHI intensities. The relative contribution of UGI decreased with the increase of building density and building height, but BH presented the opposite trend. The interaction of urban 3D landscapes and function zones led to highly complicated urban thermal environments, with higher SUHI intensities in industrial zones. Besides, the SUHI intensities of 3D neighborhoods presented great diurnal and seasonal variations, with higher SUHI intensities in HDHR and HDMR at nighttime in winter and summer. What's more, urban residents may suffer unequal heat risk inside cities due to the deviations of SUHI intensities among different 3D neighborhoods. It could be a highly effective way to mitigate SUHI effects in cities by increasing urban greening and improving urban ventilation.


Assuntos
Benchmarking , Temperatura Alta , China , Cidades , Monitoramento Ambiental/métodos , Crescimento Sustentável
6.
Sci Total Environ ; 838(Pt 2): 156214, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35618123

RESUMO

The water and energy in the land surface and lower atmosphere have a strong coupling relationship. Apart from the land surface temperature (Ts) and air temperature (Ta), the land surface-air temperature difference (Ts-Ta) is also an essential parameter reflecting the coupling process. However, the global spatiotemporal variations and influencing factors of Ts-Ta remain not well explored. Here, ERA5-land reanalysis data, GIMMS NDVI data, and elevation data were used to analyze the global spatiotemporal heterogeneity and influencing factors of Ts-Ta. It was found that annual mean Ts-Ta exhibited a decreasing trend from the equator to polar areas. And the annual Ts-Ta increased at 0.009 °C/10a from 1981 to 2020. The variations of global net radiation mainly determined the spatiotemporal heterogeneity of global Ts-Ta. The different properties of the land surface and near-surface atmosphere were the main factors affecting the Ts-Ta, including soil moisture, vegetation, snow cover, and the water vapor content in the atmosphere. In addition, Ts and Ta also affected each other. These findings are conducive to a better understanding of the land-atmosphere coupling, and it is of great significance to take better measures to adapt the global climate change.


Assuntos
Mudança Climática , Solo , Estações do Ano , Temperatura
7.
Sci Total Environ ; 822: 153607, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35114238

RESUMO

The surface-air temperature difference (Ts-Ta) is the main contributor to the sensible heat flux, and also an important indicator for land degradation. However, as the main influencing factor, the effect of soil moisture (SM) on Ts-Ta at the global scale has not been well articulated. Here, based on the ERA5-land reanalysis data from 1981 to 2019, the impacts of SM on Ts-Ta were studied. It was found that Ts-Ta over 54% of the global land increased, and SM across 70.7% of the world land decreased. In the increased SM areas, the increased soil evaporation weakened the increasing trend of Ts resulting in smaller Ts-Ta. In the decreased SM areas, the latent heat flux increased with soil evaporation and Ts-Ta decreased when SM was relatively high, and the larger sensible heat flux due to decreased soil evaporation aggravated Ts-Ta when SM was relatively low. The effect of SM on Ts-Ta presented nonlinear relationship due to the different background value of SM and temperature. The variation of SM at low SM or low temperature areas had an amplification effect on Ts-Ta. These findings will provide new insights into the different regional characteristics of global changing climate and the improvement of land degradation assessment indicators.


Assuntos
Temperatura Alta , Solo , Temperatura
8.
J Environ Manage ; 302(Pt B): 114070, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34775336

RESUMO

Understanding the impact of climate change on terrestrial wet and dry changes and the relationship between the two is of great significance to the sustainable development of terrestrial ecosystems. The farming-pastoral ecotone of northern China (FPENC) is an area that is sensitive to climate change, suffering from perennial drought and a clear aridification trend. Unlike previous single-factor, single-timescale studies, we identified aridification in the region based on a dataset established by remote sensing and ground-based monitoring stations from a combination of two perspectives: climate and soil. The results show that, in terms of climate, the period from 2000 to 2019 was the driest in the region during the last 120 years , and the summer drought was the most severe and shifted from a summer to spring drought; in terms of soil, the soil aridification trend in the region was severe, with 16.1% of the areas becoming significantly drier (P < 0.1) among the years and 41.6% in spring, respectively. Similar to climate change, soils exhibited recessive aridification due to the counterbalancing effect of the dry and wet seasons within the year. Then the coupling relationship between climate change and soil aridification was established in time and space. Moreover, the spatiotemporal response patterns of both were obtained. The results showed that the frequency of soil drought under meteorological drought conditions showed an increasing trend and that the sensitivity of soil drought occurrence increased. Among them, the effect of precipitation on relative soil moisture (RSM) was immediate, and the effect of prolonged warming on RSM is greater. The area of soil aridification that was caused by climatic aridification in spring accounted for 13.7% of the entire area. The regional aridification research mode proposed in this paper can provide ideas for subsequent studies.


Assuntos
Ecossistema , Solo , Agricultura , China , Mudança Climática
9.
J Exp Clin Cancer Res ; 40(1): 297, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34551797

RESUMO

BACKGROUND: Chemoresistance is the major cause of chemotherapy failure in patients with colorectal cancer (CRC). Protein tyrosine kinase 6 (PTK6) is aberrantly overexpressed in clinical CRC tissues undergoing chemotherapy. We studied if PTK6 contributed to the chemoresistance of CRC in human and mice. METHODS: We obtained tissue samples from patients with CRC and measured the expression of PTK6 by immunohistochemistry. Gain- and loss-of-function assays were performed to study the biological functions of PTK6. We constructed the FLAG-tagged wild type (WT), kinase-dead, and inhibition-defective recombinant mutants of PTK6 to study the effect phosphorylated activation of PTK6 played on CRC cell stemness and chemoresistance. We used small molecule inhibitor XMU-MP-2 to test the influence of PTK6 on sensitivity of CRC cells to 5-FU/L-OHP in both nude mouse and patient-derived xenograft (PDX) animal models. RESULTS: PTK6 is overexpressed in CRC tissues and plays a stimulatory role in the proliferation and chemoresistance of CRC cells both in vitro and in vivo. PTK6, especially the phosphorylated PTK6, can promote the stemness of CRC cells through interacting with JAK2 and phosphorylating it to activate the JAK2/STAT3 signaling. Pharmacological inhibition of PTK6 using XMU-MP-2 effectively reduces the stemness property of CRC cells and improves its chemosensitivity to 5-FU/L-OHP in both nude mice subcutaneously implanted tumor model and PDX model constructed with NOD-SCID mice. CONCLUSIONS: PTK6 interacts with JAK2 and phosphorylates it to activate JAK2/STAT3 signaling to promote the stemness and chemoresistance of CRC cells. Pharmacological inhibition of PTK6 by small molecule inhibitor dramatically enhances the sensitivity to chemotherapy in nude mice and PDX models.


Assuntos
Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Janus Quinase 2/metabolismo , Proteínas de Neoplasias/antagonistas & inibidores , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Fosforilação , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Front Vet Sci ; 8: 645807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791356

RESUMO

The deposition of Schistosoma japonicum (S. japonicum) eggs commonly induces inflammation, fibrosis, hyperplasia, ulceration, and polyposis in the colon, which poses a serious threat to human health. However, the underlying mechanism is largely neglected. Recently, the disorder of glucose and lipid metabolism was reported to participate in the liver fibrosis induced by the parasite, which provides a novel clue for studying the underlying mechanism of the intestinal pathology of the disease. This study focused on the metabolic reprogramming profiles of glucose and lipid in the colon of mice infected by S. japonicum. We found that S. japonicum infection shortened the colonic length, impaired intestinal integrity, induced egg-granuloma formation, and increased colonic inflammation. The expression of key enzymes involved in the pathways regulating glucose and lipid metabolism was upregulated in the colon of infected mice. Conversely, phosphatase and tensin homolog deleted on chromosome ten (PTEN) and its downstream signaling targets were significantly inhibited after infection. In line with these results, in vitro stimulation with soluble egg antigens (SEA) downregulated the expression of PTEN in CT-26 cells and induced metabolic alterations similar to that observed under in vivo results. Moreover, PTEN over-expression prevented the reprogramming of glucose and lipid metabolism induced by SEA in CT-26 cells. Overall, the present study showed that S. japonicum infection induces the reprogramming of glucose and lipid metabolism in the colon of mice, and PTEN may play a vital role in mediating this metabolic reprogramming. These findings provide a novel insight into the pathogenicity of S. japonicum in hosts.

11.
Oncogene ; 40(14): 2581-2595, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33686242

RESUMO

LIM kinase 1 (LIMK1) is a serine/threonine and tyrosine kinase that is predominantly located in the cytoplasm. In our study, nuclear translocation of LIMK1 in clinical hepatocellular carcinoma (HCC) samples was demonstrated for the first time, especially in samples from those with intravascular tumour thrombus. LIMK1 was overexpressed in HCC tissues, and nuclear LIMK1 expression was associated with poor prognosis in HCC patients. Although the effects of cytoplasmic LIMK1 on cofilin phosphorylation and actin filament dynamics have been well studied, the function of nuclear LIMK1 is still unclear. Gain- and loss-of-function experiments were performed both in vitro and in vivo and demonstrated a correlation between nuclear LIMK1 and the enhanced aggressive phenotype of HCC. EGF could drive the nuclear translocation of LIMK1 by activating the interaction of p-ERK and LIMK1 and facilitating their roles in nuclear shuttling. Moreover, nuclear LIMK1 could directly bind to the promoter region of c-Myc and stimulate c-Myc transcription. Although the EGFR monoclonal antibody cetuximab has a poor therapeutic effect on advanced HCC patients, in vivo animal study showed that cetuximab achieved a significant inhibitory effect on the progression of nuclear LIMK1-overexpressing HCC cells. In addition, recent data have demonstrated the potential of cetuximab in combination therapy for HCC patients with LIMK1 nuclear translocation.


Assuntos
Carcinoma Hepatocelular/genética , Fator de Crescimento Epidérmico/metabolismo , Genes myc/genética , Quinases Lim/metabolismo , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/patologia , Progressão da Doença , Humanos , Neoplasias Hepáticas/patologia
12.
Sci Rep ; 9(1): 17227, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754126

RESUMO

Soil moisture plays an important role in land-atmosphere interactions, agricultural drought monitoring, and water resource management, particularly across arid regions. However, it is challenging to simulate soil moisture of high spatial resolution and to evaluate soil moisture at fine spatial resolution in arid regions in Northwest China due to considerable uncertainties in forcing data and limited in situ measurements. Then, the data set was used to produce the 1 km high-resolution atmospheric forcing datasets and to drive the Community Land Model version 3.5 (CLM3.5) for simulating spatiotemporally continuous surface soil moisture. The capabilities of soil moisture simulation using CLM3.5 forced by the XJLDAS-driven field were validated against data obtained at three soil layers (0-10, 0-20, and 0-50 cm) from 54 soil moisture stations in Xinjiang. Results show that the simulated soil moisture agreed well with the observations [CORR > 0.952], and the intra-annual soil moisture in Xinjiang gradually increased during May through August. The main factors that affect changes in soil moisture across the study region were precipitation and snowmelt. The overall finding of this study is that an XJLDAS, high-resolution forcing data driven CLM3.5 can be used to generate accurate and continuous soil moisture of high resolution (1km) in Xinjiang. This study can help understand the spatiotemporal features of the soil moisture, and provide important input for hydrological studies and agricultural water resources management over the arid region.

13.
Artigo em Inglês | MEDLINE | ID: mdl-30708935

RESUMO

Urban particulate air pollution is a known cause of adverse human health effects worldwide. Urumqi is a large oasis city in which rapid urbanization has caused a series of eco-environmental problems including serious air pollution, water shortage, dense population, excess energy consumption, and the creation of an urban heat island, among others. Coal is the most important source of energy and air pollutants that are poorly dispersed into the natural surroundings are the main reasons for serious pollution in the Urumqi urban area. Using differential optical absorption spectroscopy (DOAS), aerosol levels were determined using the double optical path method. We found that aerosol concentrations in Urumqi increased rapidly in winter, and that the concentration of fine particles was much higher than that of coarse particles. The background aerosol concentration was highest in winter in the research area, and the air-flow speed had a significant impact on this because high speed surface winds that correspond to high air flows can transport the aerosol to other places. Some of the observed day-to-night differences may be caused by differing wind directions that transport air masses from different emission sources during the day and the night. Daily and seasonal differences in PM1.0 concentrations of different grades of polluted air were statistically analyzed using average daily concentration data for particles smaller than 10, 2.5 and 1.0 microns (PM10, PM2.5 and PM1.0), and meteorological observations for Urumqi, Tianshan District in 2010.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Estações do Ano , Aerossóis/análise , Poluentes Atmosféricos/química , China , Cidades , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/química , Vento
14.
Int J Cancer ; 142(9): 1853-1864, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29226323

RESUMO

Overexpression of LIM and SH3 protein 1 (LASP1) is required for colorectal cancer (CRC) development and progression. Here, C-Jun activation domain-binding protein-1 (Jab1), also known as COP9 signalosome subunit 5 (COPS5), was verified as a new LASP1-interacting protein through yeast two-hybrid assay. The role of COPS5 in LASP1-mediated CRC progression remains unknown. GST pull-down assay indicated that the SH3 domain of LASP1 could directly bind to MPN domain of COPS5. In vitro gain- and loss-of-function analyses revealed the stimulatory role of COPS5 on CRC cell proliferation, migration and invasion. Endogenous overexpression of COPS5 could also enhance the homing capacity of CRC cells in vivo. Further analysis showed that COPS5 and LASP1 synergistically interact to stimulate the ubiquitination and degradation of 14-3-3σ and promote colorectal cancer progression via PI3K/Akt dependent signaling pathway. Clinically, the expression of COPS5 was studied in CRC tissues and it is associated with CRC differentiation, metastasis and poor prognosis. The colocalization of LASP1 and COPS5 was demonstrated in both nonmetastatic and metastatic CRC tissues. A positive correlation was found between the expression of LASP1 and COPS5 while a negative correlation existed between 14-3-3σ and COPS5/LASP1 in most CRC samples. A combination of COPS5 and LASP1 tends to be an independent prognostic indicator for CRC patients, and this is also suitable for CRC without lymph node metastasis. The current research has further advanced our understanding on the complicated molecular mechanism underlying LASP1-mediated CRC progression, which hopefully will contribute to the development of novel diagnostic and therapeutic strategies in CRC.


Assuntos
Proteínas 14-3-3/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/biossíntese , Complexo do Signalossomo COP9/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas do Citoesqueleto/metabolismo , Exorribonucleases/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Peptídeo Hidrolases/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas 14-3-3/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Biomarcadores Tumorais/genética , Complexo do Signalossomo COP9/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/genética , Progressão da Doença , Regulação para Baixo , Ativação Enzimática , Exorribonucleases/genética , Células HCT116 , Células HT29 , Xenoenxertos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Camundongos , Camundongos Nus , Peptídeo Hidrolases/genética , Transdução de Sinais
15.
PLoS One ; 12(11): e0185690, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29099842

RESUMO

Understanding the regional relationships between climate change and crop production will benefit strategic decisions for future agricultural adaptation in China. In this study, the combined effects of climatic factors on spring wheat phenophase and grain yield over the past three decades in Inner Mongolia, China, were explored based on the daily climate variables from 1981-2014 and detailed observed data of spring wheat from 1981-2014. Inner Mongolia was divided into three different climate type regions, the eastern, central and western regions. The data were gathered from 10 representative agricultural meteorological experimental stations in Inner Mongolia and analysed with the Agricultural Production Systems Simulator (APSIM) model. First, the performance of the APSIM model in the spring wheat planting areas of Inner Mongolia was tested. Then, the key climatic factors limiting the phenophases and yield of spring wheat were identified. Finally, the responses of spring wheat phenophases and yield to climate change were further explored regionally. Our results revealed a general yield reduction of spring wheat in response to the pronounced climate warming from 1981 to 2014, with an average of 3564 kg·ha-1. The regional differences in yields were significant. The maximum potential yield of spring wheat was found in the western region. However, the minimum potential yield was found in the middle region. The air temperature and soil surface temperature were the optimum climatic factors that affected the key phenophases of spring wheat in Inner Mongolia. The influence of the average maximum temperature on the key phenophases of spring wheat was greater than the average minimum temperature, followed by the relative humidity and solar radiation. The most insensitive climatic factors were precipitation, wind speed and reference crop evapotranspiration. As for the yield of spring wheat, temperature, solar radiation and air relative humidity were major meteorological factors that affected in the eastern and western Inner Mongolia. Furthermore, the effect of the average minimum temperature on yield was greater than that of the average maximum temperature. The increase of temperature in the western and middle regions would reduce the spring wheat yield, while in the eastern region due to the rising temperature, the spring wheat yield increased. The increase of solar radiation in the eastern and central regions would increase the yield of spring wheat. The increased air relative humidity would make the western spring wheat yield increased and the eastern spring wheat yield decreased. Finally, the models describing combined effects of these dominant climatic factors on the maturity and yield in different regions of Inner Mongolia were used to establish geographical differences. Our findings have important implications for improving climate change impact studies and for local agricultural production to cope with ongoing climate change.


Assuntos
Clima , Produtos Agrícolas , Estações do Ano , Triticum/fisiologia , China , Solo , Luz Solar , Triticum/crescimento & desenvolvimento
16.
Br J Cancer ; 117(4): 563-571, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28664914

RESUMO

BACKGROUND: LIM kinase 1 (LIMK1) is a key regulator of the cytoskeletal organisation involved in cell proliferation and migration. Even though LIMK1 is frequently dysregulated in epithelial cancers, the role and mechanisms of LIMK1 in colorectal cancer (CRC) remains unclear. METHODS: Immunohistochemical analysis was performed to examine the expression and clinical significance of LIMK1 in CRC samples. Loss- and gain-of-function assay was performed to investigate the effects of aberrant expression on cellular biological behaviour of CRC cells in vitro and in vivo. Immunoblotting and immunoprecipitation was used to screen LIMK1-related signalling pathways and downstream factors. RESULTS: In this study, our results showed that LIMK1 was upregulated in CRC tissues and localised in both the cytoplasm and the nucleus of CRC cells. Overexpression of LIMK1 in cytoplasmic and nuclear subcellular compartments was closely related to tumour metastasis and poor prognosis of CRC patients. Enhanced expression of cytoplasmic and nuclear LIMK1 significantly increased cell proliferation and migration by driving epithelial-mesenchymal transition and activating the PI3K/Akt signal pathway in vitro as well as promoting growth and metastasis of CRC xenografts, whereas opposite effects were achieved in LIMK1-silenced cells. Furthermore, we identified two tumour metastasis-associated proteins, MYH9 and ACTN4, as direct targets of LIMK1, which were required for a LIMK1-mediated aggressive phenotype. CONCLUSIONS: These findings indicate that LIMK1 plays a critical role in promoting CRC progression at subcellular level. Our findings provide new insights into the metastasis of CRC and advocate for the development of clinical intervention strategies against advanced CRC.


Assuntos
Actinina/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Quinases Lim/metabolismo , Proteínas Motores Moleculares/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Núcleo Celular/química , Proliferação de Células , Neoplasias Colorretais/química , Neoplasias Colorretais/genética , Citoplasma/química , Progressão da Doença , Transição Epitelial-Mesenquimal , Inativação Gênica , Humanos , Quinases Lim/análise , Quinases Lim/genética , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fenótipo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Regulação para Cima
17.
Int J Clin Exp Pathol ; 10(11): 11353-11359, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31966490

RESUMO

Colon cancer is the third most common cancer diagnosed in both men and women worldwide and one of the leading causes of cancer-related deaths. Based on where the cancer stared, we focused on the left-sided colon cancer and right-sided colon cancer in this study to reveal their pathological characteristics and their relationship to the KRAS gene mutation. From examining a total of 198 colorectal cancer specimens collected during 2013 and 2016 in Nan fang Hospital, we noticed that whether the cancer developed in left side or right side of the colon are highly relevant to the patients gender, age, tumor size, differentiation and distant metastasis. We found that right-sided colon cancers (RCC) are more likely to occur in women, be greater than 5 cm, and occur in patients older than 60 years, while left-sided colon cancers (LCC) are more prevalent in patients with poorly differentiated tumors and tumors with distant metastases. We then randomly selected 113 of the 198 samples and performed Sanger sequencing to examine their KRAS gene mutation. The result indicates that KRAS mutation is prominently higher in RCC compare to LCC, especially the mutation on the 12th codon GGT>GAT (G12D). In addition to the location in which the cancer developed, the KRAS mutation was also closely associated with the tumor size, degree of tumor differentiation, and lymph node metastasis. There was a significantly higher incidence of KRAS mutation in cases with RCC, poorly differentiated tumors, and non-lymph node metastasis compared to LCC with well- or moderately differentiated tumors with lymph node metastasis. Taken together, we determined that there are distinct differences in the clinicopathological characteristics of right-versus left-sided colon cancers and their correlation with the KRAS mutation. These differences suggest that practitioners need to diagnose and treat RCC and LCC differently.

18.
Int J Biometeorol ; 61(5): 911-919, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27913871

RESUMO

Representing an important greenhouse gas, nitrous oxide (N2O) emission from cultivated land is a hot topic in current climate change research. This study examined the influences of nitrogen fertilisation, temperature and soil moisture on the ammonia monooxygenase subunit A (amoA) gene copy numbers and N2O emission characteristics. The experimental observation of N2O fluxes was based on the static chamber-gas chromatographic method. The ammonia-oxidising bacteria (AOB) and ammonia-oxidising archaea (AOA) gene copy numbers in different periods were measured by real-time polymerase chain reaction (PCR). The results indicated that rain-fed potato field was a N2O source, and the average annual N2O emission was approximately 0.46 ± 0.06 kgN2O-N/ha/year. N2O emissions increased significantly with increase in fertilisation, temperatures below 19.6 °C and soil volumetric water content under 15%. Crop rotation appreciably decreases N2O emissions by 34.4 to 52.4% compared to continuous cropping in rain-fed potato fields. The significant correlation between N2O fluxes and AOB copy numbers implied that N2O emissions were primarily controlled by AOB in rain-fed potato fields. The research has important theoretical and practical value for understanding N2O emissions from rain-fed dry farmland fields.


Assuntos
Poluentes Atmosféricos/análise , Óxido Nitroso/análise , Microbiologia do Solo , Solanum tuberosum , Agricultura/métodos , Amônia/metabolismo , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , China , Fertilizantes , Dosagem de Genes , Genes Arqueais , Genes Bacterianos , Oxirredução , Oxirredutases/genética , Chuva , Temperatura
19.
Sci Total Environ ; 573: 965-973, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27599060

RESUMO

Understanding the effects of climate change on crops is vital for food security. We aimed to characterise the coincidence of yield variations with weather variable for potato in northern China using long-term datasets. Daily climate variables obtained from 607 meteorological stations from 1961 to 2014, detailed field experimental data for the period of 1982 to 2012 in northern China, and multivariate linear statistical model were used in this study. In particular, the first difference method was used to disentangle the contributions of climate change to potato yield. We concluded that during the potato growing, the average daily, maximum and minimum temperatures significantly increased by 0.23°C per decade, 0.20°C per decade and 0.36°C per decade from 1961 to 2014 in northern China, respectively. However, average total radiation, total annual precipitation and potential evapotranspiration from April to September all exhibited downward trends, but the variation of evapotranspiration (-9.99mm per decade) was greater than that of precipitation (-2.65mm per decade). The key climatic factors limiting potato yields in northern China over the past 30years at a regional scale were diurnal temperature range, precipitation, radiation and ET0. The potato yield in northern China was the most sensitive to variation of the diurnal temperature range followed by radiation, precipitation and reference crop evapotranspiration (ET0). Specifically, when the diurnal temperature range decreased 1°C, the potato yield increased 543.9kg·ha-1. When the total radiation decreased 1MJ·m2, the potato yield increased 63.8kg·ha-1. When the ET0 decreased 1mm, the potato yield increased 62.7kg·ha-1. When the precipitation increased 1mm, the potato yield increased 62.9kg·ha-1. A regression model describing the combined effects of different climate variables on potato yield in northern China was established.

20.
PLoS One ; 10(9): e0137409, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26336098

RESUMO

It has long been concerned how crop water use efficiency (WUE) responds to climate change. Most of existing researches have emphasized the impact of single climate factor but have paid less attention to the effect of developed agronomic measures on crop WUE. Based on the long-term field observations/experiments data, we investigated the changing responses of crop WUE to climate variables (temperature and precipitation) and agronomic practices (fertilization and cropping patterns) in the semi-arid area of northern China (SAC) during two periods, 1983-1999 and 2000-2010 (drier and warmer). Our results suggest that crop WUE was an intrinsical system sensitive to climate change and agronomic measures. Crops tend to reach the maximum WUE (WUEmax) in warm-dry environment while reach the stable minimum WUE (WUEmin) in warm-wet environment, with a difference between WUEmax and WUEmin ranging from 29.0%-55.5%. Changes in temperature and precipitation in the past three decades jointly enhanced crop WUE by 8.1%-30.6%. Elevated fertilizer and rotation cropping would increase crop WUE by 5.6-11.0% and 19.5-92.9%, respectively. These results indicate crop has the resilience by adjusting WUE, which is not only able to respond to subsequent periods of favorable water balance but also to tolerate the drought stress, and reasonable agronomic practices could enhance this resilience. However, this capacity would break down under impact of climate changes and unconscionable agronomic practices (e.g. excessive N/P/K fertilizer or traditional continuous cropping). Based on the findings in this study, a conceptual crop WUE model is constructed to indicate the threshold of crop resilience, which could help the farmer develop appropriate strategies in adapting the adverse impacts of climate warming.


Assuntos
Mudança Climática , Clima , Produtos Agrícolas , Secas , Água , China , Fertilizantes
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