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1.
Vet Med Sci ; 8(1): 177-186, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34561963

RESUMO

BACKGROUND: Tibetan pigs have exhibited unique characteristics from low-altitudes pigs and adapted well to the Qinghai-Tibet Plateau. OBJECTIVES: The current study was undertaken to investigate the hypoxic adaptation of heart in Tibetan pigs. METHODS: The hearts of Tibetan pigs and Landrace pigs raised at high or low altitudes were compared using 3D casting technology, scanning electron microscopy and real-time quantitative PCR (qRT-PCR). RESULTS: We found that the ratio of the major axis to the minor axis and the density of the heart were significantly higher in Tibetan pigs than in Landrace pigs (p < 0.05). Tibetan pigs had larger diameters and higher densities of arterioles than Landrace pigs (p < 0.05), and these features have a similar variation with the expression of vascular endothelial growth factor (VEGF). The cardiac expression levels of hypoxia-inducible factor-1α (HIF-1α) and endothelial nitric oxide synthase (eNOS) were significantly higher in pigs reared at high altitudes than in those reared at low altitudes (p < 0.05). In contrast, Egl nine homolog 1 (EGLN1) had the opposite trend with respect to HIF-1α and eNOS and was related to red blood cell (RBC) counts. Notably, the expressions of erythropoietin (EPO) and endothelial PAS domain-containing protein 1 (EPAS1) were significantly higher in Landrace pigs kept at high altitudes than in the others (p < 0.05) and were associated with haemoglobin. CONCLUSIONS: These findings show that the regulation of the heart function of Tibetan pigs in a hypoxic environment is manifested at various levels to ensure the circulation of blood under extreme environmental conditions.


Assuntos
Altitude , Fator A de Crescimento do Endotélio Vascular , Aclimatação/genética , Animais , Hipóxia/genética , Hipóxia/veterinária , Suínos/genética , Tibet , Fator A de Crescimento do Endotélio Vascular/genética
2.
Front Genet ; 12: 691592, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691141

RESUMO

To adapt to a low-oxygen environment, Tibetan pigs have developed a series of unique characteristics and can transport oxygen more effectively; however, the regulation of the associated processes in high-altitude animals remains elusive. We performed mRNA-seq and miRNA-seq, and we constructed coexpression regulatory networks of the lung tissues of Tibetan and Landrace pigs. HBB, AGT, COL1A2, and EPHX1 were identified as major regulators of hypoxia-induced genes that regulate blood pressure and circulation, and they were enriched in pathways related to signal transduction and angiogenesis, such as HIF-1, PI3K-Akt, mTOR, and AMPK. HBB may promote the combination of hemoglobin and oxygen as well as angiogenesis for high-altitude adaptation in Tibetan pigs. The expression of MMP2 showed a similar tendency of alveolar septum thickness among the four groups. These results indicated that MMP2 activity may lead to widening of the alveolar wall and septum, alveolar structure damage, and collapse of alveolar space with remarkable fibrosis. These findings provide a perspective on hypoxia-adaptive genes in the lungs in addition to insights into potential candidate genes in Tibetan pigs for further research in the field of high-altitude adaptation.

3.
Arch Anim Breed ; 64(1): 283-292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235247

RESUMO

To adapt to the plateau environment, Tibetan pigs' lungs have developed a unique physiological mechanism during evolution. The vascular corrosion casting technique and scanning electron microscopy were used to understand arterial architecture. Blood physiological index and quantitative real-time PCR (qRT-PCR) were used for assessing whether the lung can regulate the body through anatomical, physiological and molecular mechanisms to adapt to hypoxic environments. Our study showed that the lungs of Tibetan pigs were heavier and wider and that the pulmonary arteries were thicker and branched and had a denser vascular network than those of Landrace pigs. The hemoglobin (HGB), mean corpuscular hemoglobin concentration (MCHC) values of high-altitude pigs were significantly higher than those of low-altitude pigs. The expression levels of HIF- 1 α , EPAS1, EPO and VEGF, but not those of eNOSand EGLN1, were significantly higher in the lungs of high-altitude pigs than in those from pigs at a lower altitude ( P < 0.05 ). These findings and a comprehensive analysis help elucidate the pulmonary mechanism of hypoxic adaptation in pigs.

4.
Ground Water ; 58(2): 278-290, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31131880

RESUMO

Excessive groundwater withdrawal has caused severe land subsidence worldwide. The pore water pressure and the deformation of pumped hydrostratigraphic units are complex. A fully coupled three-dimensional numerical simulation was carried out for different pumping plans in this paper. When groundwater is pumped from a confined aquifer, the great compaction occurs in the pumped aquifer and its upper and lower adjacent aquitard units. Land subsidence is smaller and the area affected by land subsidence is greater when groundwater is pumped from the deeper confined aquifer. The pore water pressure in the pumped confined aquifer changes immediately with pumpage. In the adjacent aquitard units, however, the pore water pressure increases in the early pumping time and decreases in the early recharging time. The decrease in the pore water pressure vertically spreads from the interface between aquitard and pumped aquifer to the other surface of the aquitard. The pumped aquifer compacts and rebounds immediately with pumping and non-pumping or recharging actions, while the compaction and rebounding of the aquitard units clearly lag behind. The compaction of the adjacent aquitard unit first occurs near the interface between aquitard and pumped aquifer units, and the compaction zone spreads outward as the pumping goes on. The aquitards may expand vertically within some zones. Due to the inelastic deformation of soil skeleton, different pumping plans result in different land subsidence. For the same net pumpage, maximal land subsidence and horizontal displacement are the smallest for constant discharge and the greatest for recharge-discharge cycle.


Assuntos
Água Subterrânea , Solo , Água , Movimentos da Água
5.
Sci Total Environ ; 702: 134939, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31733561

RESUMO

Large-scale contaminated dredger fills have comprehensively resulted from human activities and geological deposition processes, and their disposal is a worldwide challenge. Innovative soil remediation coupling foundation treatment methods, namely, clean foundation treatment methods (CFTMs), were proposed and verified using a hydraulic-mechanical-chemical coupling triaxial testing system. The CFTM exploration triaxial tests on undisturbed clayey, silty, and sandy dredger fills showed that the critical injection significantly dilated soil volume even after the soil was vacuum pumped. Critical injection-vacuum soil flushing (CIVF), critical injection soil flushing (CIF), and vacuum soil flushing (VF) were proposed to perform clean foundation treatment for clayey silt, sandy silt, and silty sand of 1900-2300 ppm Zn. EDDS, HCl + CaCl2, and HCl were selected as the three chelating agents. Orthogonal tests on three factors (CFTM, soil type, and eluent) showed that CIF with 5:1 EDDS aq. of pH 3.8 was the best CFTM scheme for the three soil types at a depth of 2.5-10 m. CIF with HCl aq. of pH 3.8 also reached a high comprehensive clean foundation treatment efficiency for silty sand at a depth of 2.5 m. The deep depth and heterogeneous texture resulted in low Zn contamination extraction efficiency.

6.
Mar Pollut Bull ; 149: 110496, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31425848

RESUMO

Heavy metal elements, including Zn, Cd, As, Ni, Cu, Pb and Cr, were detected in soils (no deeper than 75 m) from newly reclaimed zones of Shanghai, China. The Zn concentration exceeded soil quality limits. The Zn contamination was tested in both dredger fills and sedimentary layers (①3-3, ②3, ④ and ⑤1-1). However, it was not detected in layer ⑤1-2-⑨. PCA and HCA analysis show that exogenous Zn probably was the contaminant source of dredger fills before the fills were dredged from the neighboring waters. Stochastic heterogeneity of the dredger fills affects the Zn-depollution remarkably. Numerical simulations show both acid precipitation and widespread drainage channels in the zones contributed to Zn-decrease in the dredger fills no deeper than 1.2 m. Acid rainstorms work better than acid constant precipitation in Zn-remediation for layers below 0.4 m. To remove Zn contamination in deep dredger fills, un-consolidation of the fills should be utilized.


Assuntos
Poluentes do Solo , Zinco , China , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise , Zinco/análise
7.
Artigo em Inglês | MEDLINE | ID: mdl-31370177

RESUMO

Land subsidence was once a major geo-hazard in the city of Shanghai, China. From 1921 to 1965, the maximum cumulative land subsidence in the urban areas of China reached 2.6 m. This large subsidence has resulted in high economic losses for Shanghai. The Regulation of Prevention and Control of Land Subsidence of Shanghai Municipality was published in 2013 (simply cited as the 2013-regulation in the following context). The characteristics of the 2013-regulation included the combination of the subsidence monitoring network and the groundwater detection network due to both the effects of groundwater withdrawal and construction. In addition, the setting up of a supervision system was also incorporated in the 2013-regulation. To control the land subsidence, Shanghai demarcated three land subsidence control zones, where special measures have been implemented. From a strategic environmental assessment (SEA) point of view, the 2013-regulation attains a high total score, indicating that the control of groundwater withdrawal and recharge is effective. The observed land subsidence over the past six years also confirms the effectiveness of the 2013-regulation with the most consideration of SEA for sustainable environment protection in Shanghai. However, more effort should be made in the implementation of SEA in land subsidence control in the future.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Monitoramento Ambiental/legislação & jurisprudência , Política Ambiental , China , Cidades , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Hídricos/legislação & jurisprudência , Conservação dos Recursos Hídricos/métodos , Monitoramento Ambiental/métodos , Regulamentação Governamental , Água Subterrânea
8.
Sensors (Basel) ; 17(12)2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29186039

RESUMO

Since the Persistent Scatterer Synthetic Aperture Radar (SAR) Interferometry (PSI) technology allows the detection of ground subsidence with millimeter accuracy, it is becoming one of the most powerful and economical means for health diagnosis of major transportation infrastructures. However, structures of different types may suffer from various levels of localized subsidence due to the different structural characteristics and subsidence mechanisms. Moreover, in the complex urban scenery, some segments of these infrastructures may be sheltered by surrounding buildings in SAR images, obscuring the desirable signals. Therefore, the subsidence characteristics on different types of structures should be discussed separately and the accuracy of persistent scatterers (PSs) should be optimized. In this study, the PSI-based subsidence mapping over the entire transportation network of Shanghai (more than 10,000 km) is illustrated, achieving the city-wide monitoring specifically along the elevated roads, ground highways and underground subways. The precise geolocation and structural characteristics of infrastructures were combined to effectively guide more accurate identification and separation of PSs along the structures. The experimental results from two neighboring TerraSAR-X stacks from 2013 to 2016 were integrated by joint estimating the measurements in the overlapping area, performing large-scale subsidence mapping and were validated by leveling data, showing highly consistent in terms of subsidence velocities and time-series displacements. Spatial-temporal subsidence patterns on each type of infrastructures are strongly dependent on the operational durations and structural characteristics, as well as the variation of the foundation soil layers.

9.
Int J Psychophysiol ; 100: 44-51, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26386395

RESUMO

A great deal of evidence suggests that emotion enhances memory. Thus, it may be harder to forget emotional information. By means of fMRI, this question was investigated in the item-method directed forgetting paradigm. Behavioral results demonstrated that although all kinds of material could be forgotten, negative words showed reduced directed forgetting effect. At the neural level, the initial viewing of negative words elicited increased activities in inferior frontal gyrus and superior parietal lobule when contrasted with neutral words, which reflected the capture of attention by negative content. Forgetting instructions for negative and neutral words led to enhanced activations in frontal and parietal cortex, consistent with the engagement of an active inhibitory process. Surprisingly, whereas successful directed forgetting of neutral words elicited stronger activations in right middle frontal gyrus compared with incidental forgetting, no such activation was observed for negative words. The lack of activation for negative words may be due to an attentional bias in processing negative words, which may briefly interfere with the deployment of inhibitory control. The present findings are consistent with the engagement of an active forgetting mechanism that contributes to the item-method directed forgetting. However, evidence of impeded inhibitory control suggests that forgetting negative words is harder.


Assuntos
Encéfalo/irrigação sanguínea , Inibição Psicológica , Transtornos da Memória/patologia , Transtornos da Memória/fisiopatologia , Adulto , Análise de Variância , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Adulto Jovem
10.
Neurosci Bull ; 31(6): 663-75, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26552800

RESUMO

Neuroimaging techniques such as functional magnetic resonance imaging and positron emission tomography have provided an unprecedented neurobiological perspective for research on personality traits. Evidence from task-related neuroimaging has shown that extraversion is associated with activations in regions of the anterior cingulate cortex, dorsolateral prefrontal cortex, middle temporal gyrus and the amygdala. Currently, resting-state neuroimaging is being widely used in cognitive neuroscience. Initial exploration of extraversion has revealed correlations with the medial prefrontal cortex, anterior cingulate cortex, insular cortex, and the precuneus. Recent research work has indicated that the long-range temporal dependence of the resting-state spontaneous oscillation has high test-retest reliability. Moreover, the long-range temporal dependence of the resting-state networks is highly correlated with personality traits, and this can be used for the prediction of extraversion. As the long-range temporal dependence reflects real-time information updating in individuals, this method may provide a new approach to research on personality traits.


Assuntos
Encéfalo/fisiologia , Extroversão Psicológica , Neuroimagem Funcional/métodos , Introversão Psicológica , Humanos
11.
PLoS One ; 10(9): e0133775, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26327292

RESUMO

Recent developments in graph theory have heightened the need for investigating the disruptions in the topological structure of functional brain network in major depressive disorder (MDD). In this study, we employed resting-state functional magnetic resonance imaging (fMRI) and graph theory to examine the whole-brain functional networks among 42 MDD patients and 42 healthy controls. Our results showed that compared with healthy controls, MDD patients showed higher local efficiency and modularity. Furthermore, MDD patients showed altered nodal centralities of many brain regions, including hippocampus, temporal cortex, anterior cingulate gyrus and dorsolateral prefrontal gyrus, mainly located in default mode network and cognitive control network. Together, our results suggested that MDD was associated with disruptions in the topological structure of functional brain networks, and provided new insights concerning the pathophysiological mechanisms of MDD.


Assuntos
Encéfalo/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Neuroimagem Funcional , Imageamento por Ressonância Magnética , Adulto , Estudos de Casos e Controles , Feminino , Giro do Cíngulo/fisiopatologia , Hipocampo/fisiopatologia , Humanos , Masculino , Modelos Biológicos , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Lobo Temporal/fisiopatologia
12.
Zhongguo Zhong Yao Za Zhi ; 31(17): 1445-6, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17087087

RESUMO

OBJECTIVE: To compare the ingredients of essential oils of Curcuma wenyujin extracted by supercritical-CO2 fluid extraction and by steam distillation. METHOD: GC-MS was applied in this experiment. RESULT: The ingredients and physical and chemical properties of essential oils of C. wenyujin extracted by supercritical-CO2 fluid extraction and by steam distillation are similar. CONCLUSION: Supercritical-CO2 fluid extraction is better than steam distillation in extraction time, power consumption, recovery and purity.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Curcuma/química , Óleos Voláteis/isolamento & purificação , Plantas Medicinais/química , Dióxido de Carbono , Óleos Voláteis/química , Rizoma/química , Volatilização
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