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1.
J Environ Manage ; 348: 119184, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37832291

RESUMEN

Grazing and climate change both contribute to diversity loss and productivity fluctuations. Sensitive climate conditions and long-term grazing activities have a profound influence on community change, particularly in high-altitude mountain grassland ecosystems. However, knowledge about the role of long-term continuous grazing management on diversity, productivity and the regulation mechanisms in fragile grassland ecosystems is still rudimentary. We conducted a long-term grazing experiment on an alpine typical steppe in the Qilian Mountains to assess effects of grazing intensity on soil, diversity, productivity and the regulation mechanisms. Plants and soil were sampled along grazing gradients at different distances from the pasture entrance (0, 0.3, 0.6, 0.9, 1.2 and 1.5 km) under the non-growing (WP) and the growing season grazing pasture (SAP). The results revealed that community diversity and biomass did not change significantly on a time scale, while the concentration of soil organic carbon and total phosphorus increased significantly. Heavy grazing (0-0.3 km) decreased community diversity and biomass. Grazing increased soil chemical properties in heavy grazed areas of WP, while the opposite was recorded in SAP. Soil chemical properties explained the largest variances in community diversity and community biomass. The prediction model indicates that grazing in WP mainly affects community diversity through soil chemical properties, and promotes a positive correlation between community diversity and community biomass; in SAP, the direct effect of grazing gradients on community diversity and biomass is the main pathway, but not eliminating the single positive relationship between diversity and biomass, which means that diversity can still be used as a potential resource to promote productivity improvement. Therefore, we should focus on the regulation of soil chemical properties in WP, such as the health and quality of soil, strengthening its ability to store water, sequester carbon and increase nutrients; focus on the management of livestock in SAP, including providing fertilizer and sowing to increase diversity and production in heavily grazed regions and reducing grazing pressure through regional rotational grazing. Ultimately, we call for strengthening the stability and sustainability of ecosystems through targeted and active human intervention in ecologically sensitive areas to cope with future grazing pressures and climate disturbances.


Asunto(s)
Ecosistema , Pradera , Humanos , Suelo/química , Carbono , Biomasa
2.
Ying Yong Sheng Tai Xue Bao ; 33(1): 180-190, 2022 Jan.
Artículo en Chino | MEDLINE | ID: mdl-35224940

RESUMEN

Clarifying the regional natural capital utilization and its spatial effects and influencing factors has important theoretical and practical significance for regional sustainable development. Here, we used a three-dimensional ecological footprint model, exploratory spatial data analysis, a spatial Markov chain, and a spatial panel Durbin model to explore the spatial effects and influencing factors of overall and subcategory natural capital flow and stock occupancy of 112 prefecture-level cities in the Yangtze River Economic Belt from 2008 to 2018. The results showed that the total, per capita, and subcategory natural capital flow and stock occupancy increased during the study period. Most of the regions with low overall and subcategory natural flow occupancy were located in the East, whereas most of the regions with high overall and subcategory natural flow occupancy were mostly located in the Central and Wes-tern area. However, their stock occupancy behaved differently. Except for farmland stock, the overall and subcategory natural capital flow and stock occupancy showed spatial agglomeration. The traditional and spatial Markov chain presented a "Matthew effect" and a "spatial spillover effect" in natural capital flow and stock occupancy. Economic growth and industrial structure positively affected natural capital flow and stock occupancy. Population growth positively affected natural capital flow occupancy. Urbanization rate negatively affected natural capital flow occupancy, and positively impacted natural capital stock occupancy. Government intervention negatively affected the farmland flow and fossil fuels land stock occupancy. Environmental governance negatively affected the natural capital flow occupancy, but positively affected the natural capital stock occupancy. Environmental pollution positively affected natural capital flow and stock occupancy.


Asunto(s)
Conservación de los Recursos Naturales , Ríos , China , Ciudades , Desarrollo Económico , Política Ambiental , Urbanización
3.
Am J Transl Res ; 14(12): 8457-8472, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36628246

RESUMEN

Distinguishing between N6-methyladenosine (m6A)-associated long noncoding RNAs (lncRNAs) is crucial in non-small-cell lung cancer (NSCLC) patients. In this research, the prognosis and immunotherapeutic response of lncRNAs and m6A in NSCLC were examined. lncRNAs related to m6A were identified using co-expression analyses, and their prognostic impact on patients with NSCLC was assessed using univariate Cox regression analysis. Sixty-three m6A-associated lncRNAs were determined as prognostic lncRNAs, and on this basis, 25 m6A-associated lncRNAs were screened by least absolute shrinkage and selection operator (lasso) Cox regression. Multivariable Cox analysis obtained 14 m6A-associated lncRNAs for the construction of risk model. The NSCLC patients were grouped into different risk subgroups in accordance with the median of the risk fraction in each data, and we evaluated the differences of potential immunotherapeutic characteristics and drug sensitivity prediction between the two subgroups. By using this model to recombine patients, they can be effectively distinguished in terms of the immunotherapy response. Furthermore, candidate compounds for the differentiation of NSCLC subtypes were identified. The model based on 14 m6A-associated lncRNAs is a promising prognostic biomarker, which may help to predict the efficacy of immunotherapy in NSCLC patients and provide a theoretical basis for improving the outcome of patients.

4.
PLoS One ; 10(6): e0127257, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26053874

RESUMEN

Gynaephora (Lepidoptera Erebidae: Lymantriinae) is a small genus, consisting of 15 nominated species, of which eight species are endemic to the Qinghai-Tibetan Plateau (QTP). In this study, we employed both mitochondrial and nuclear loci to infer a molecular phylogeny for the eight QTP Gynaephora spp. We used the phylogeny to estimate divergence dates in a molecular dating analysis and to delimit species. This information allowed us to investigate associations between the diversification history of the eight QTP species and geological and climatic events. Phylogenetic analyses indicated that the eight QTP species formed a monophyletic group with strong supports in both Bayesian and maximum likelihood analyses. The low K2P genetic distances between the eight QTP species suggested that diversification occurred relatively quickly and recently. Out of the eight species, five species were highly supported as monophyletic, which were also recovered by species delimitation analyses. Samples of the remaining three species (G. aureata, G. rouergensis, and G. minora) mixed together, suggesting that further studies using extensive population sampling and comprehensive morphological approaches are necessary to clarify their species status. Divergence time estimation results demonstrated that the diversification and speciation of Gynaephora on the QTP began during the late Miocene/early Pliocene and was potentially affected by the QTP uplift and associated climate changes during this time.


Asunto(s)
Pradera , Lepidópteros/genética , Filogenia , Animales , Datos de Secuencia Molecular , Polimorfismo Genético , Análisis de Secuencia de ADN , Programas Informáticos , Especificidad de la Especie , Tibet , Factores de Tiempo
5.
Huan Jing Ke Xue ; 35(5): 1832-7, 2014 May.
Artículo en Chino | MEDLINE | ID: mdl-25055674

RESUMEN

High salinity wastewater is one of the difficulties in the field of wastewater treatment. As a new desalination technology, electrosorption technology has many advantages. This paper studied a new type of carbon-based electrodes, the graphite and activated carbon fiber composite electrodes. And the influencing factors of electrosorption and its desalination effect were investigated. The electrosorption device had optimal desalination effect when the voltage was 1. 6 V, the retention time was 60 min and the plate spacing was 1 cm. The graphite and activated carbon fiber composite electrodes were used to treat the black liquor of refined cotton and sodium copper chlorophyll wastewater to investigate its desalination effect. When the electrodes were used to treat the black liquor of refined cotton after acid treatment, the removal rate of conductivity and COD reached 58. 8% and 75. 6% respectively when 8 pairs of electrodes were used. And when the electrode was used to treat the sodium copper chlorophyll wastewater, the removal rate of conductivity and COD reached higher than 50. 0% and 13. 5% respectively when 6-8 pairs of electrodes were used.


Asunto(s)
Carbón Orgánico/química , Grafito/química , Aguas Residuales/química , Purificación del Agua/métodos , Electrodos , Iones , Salinidad , Sales (Química) , Purificación del Agua/instrumentación
6.
BMC Cancer ; 14: 280, 2014 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-24758329

RESUMEN

BACKGROUND: Malignant pleural effusion (MPE) is a common complication of advanced lung cancer. Research has shown that secreted phosphoprotein-1 (SPP1) is essential in MPE associated with lung cancer. This retrospective study was performed to evaluate the prognostic significance of SPP1 in the MPE of patients with non-small cell lung cancer (NSCLC). METHODS: MPE specimens were obtained from 85 NSCLC patients (study group), and pleural effusion specimens were obtained from 24 patients with benign lung disease (control group). Specimens were tested for SPP1 using enzyme-linked immunosorbent assay (ELISA). Based on the cutoff value of receiver operating characteristic (ROC) curve analysis, the study patients were divided into a high-SPP1-expression subgroup and a low-expression subgroup. The primary and secondary endpoints of this study were progression-free survival (PFS) and overall survival (OS). RESULTS: The SPP1 levels of the study group were significantly higher compared to those of the controls (Mann-Whitney U test, P = 0.017). The number of extrapulmonary metastases was significantly higher in the high-SPP1-expressing patients than in the low-expressing patients (P = 0.03). Kaplan-Meier survival analysis showed that SPP1 levels were negatively associated with OS and PFS in both subgroups of study patients (P = 0.026; P = 0.039, respectively). Cox regression analysis showed that SPP1 was an independent prognostic factor in patients with NSCLC (HR = 1.832, 95% confidence interval: 1.003-3.345; P = 0.049). CONCLUSION: SPP1 in pleural effusion can be used for the auxiliary diagnosis of MPE and used to determine the prognosis of patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Osteopontina/genética , Pronóstico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Osteopontina/biosíntesis
7.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(1): 121-4, 2013 Feb.
Artículo en Chino | MEDLINE | ID: mdl-23469802

RESUMEN

GATA transcription factor family members have been found to involve in the growth and differentiation of mammary gland. Among them GATA-3 is regarded as the most critical regulator involving the tumorigenesis of breast cancer (BC). Recently, trichorhinophalangeal syndrome-1 gene (TRPS-1), a new GATA family member, has been identified to be highly prevalent in breast cancer. Compared with ER-negative breast cancer, the expression of TRPS-1 is higher in ER-positive breast cancer and was significantly correlates with estrogen receptor, progesterone receptor, and GATA-3, indicating it may serve as a ductal epithelial cell-specific regulator in the differentiation of breast ductal epithelial cells. Studies have shown that miR221/222 is able to downregulate the expression of an epithelial cell marker E-cadherin by targeting TRPS-1, resulting in mammary epithelial cells transition to mesenchymal cell (EMT). In addition, it has been well accepted that, and the Science and Technology Bureau of Jiaxing (2012AY1071-2)TRPS-1 plays a role in the differentiation of several other cell types including kidney nephric mesenchymal cells, columnar chondrocytes, and osteoclasts, indicating that TRPS-1 involves in mesenchymal-to-epithelial cell transition (MET). In this article, we summarize the roles of GATA transcription factor TRPS-1 in ductal epithelial cells and the roles of its gene and protein expressions in predicting the prognosis of breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Proteínas de Unión al ADN/genética , Factores de Transcripción/genética , Neoplasias de la Mama/patología , Transición Epitelial-Mesenquimal , Femenino , Factor de Transcripción GATA3/genética , Humanos , Proteínas Represoras
8.
Zhonghua Yi Xue Za Zhi ; 93(38): 3027-30, 2013 Oct 15.
Artículo en Chino | MEDLINE | ID: mdl-24417921

RESUMEN

OBJECTIVE: To explore the protein-tyrosine-phosphatase 1B (PTP1B) expression and its prognostic significance in non-small-cell lung cancer (NSCLC). METHODS: Immunohistochemical method of EnVision was applied to investigate the expression of PTP1B in lung specimens from 63 cases with NSCLC and 9 cases with pneumonia confirmed by pathological examination after surgical removals at Jinling Hospital from June 2000 to October 2010. The data of PTP1B expression in different lung tissues and its relationship with clinicopathological features and prognostic value for survival were analyzed by chi-square test, Kaplan-Meire survival analysis, Log rank test and multivariable Cox regression analysis. RESULTS: The expression of PTP1B was negative in pneumonia group while positive in NSCLC tissues (32/63, 50.8%) (χ(2) = 8.229, P = 0.004). The expression of PTP1B in NSCLC tissue was not correlated with gender, age, smoking history, tumor size, pathological type, lymph node metastasis and chemotherapy, but significantly associated with pTNM staging (χ(2) = 6.426, P = 0.040). Kaplan-Meire survival analysis showed that the expression of PTP1B was significantly correlated with overall survival (Log-rank, P = 0.047). Multivariable Cox regression analysis indicated that both PTP1B (HR = 2.050, P = 0.044) and pTNM staging (HR = 3.631, P = 0.000) were independent prognostic factors for NSCLC. CONCLUSIONS: PTP1B may be a biomarker for differential diagnosis of malignant lung disease. And PTP1B and pTNM were independent prognostic factors for NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Pulmón/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neumonía/patología , Pronóstico
9.
Org Lett ; 12(4): 720-3, 2010 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-20104883

RESUMEN

The direct asymmetric allylic alkylation of beta,gamma-butenolides with MBH carbonates to access gamma,gamma-disubstituted butenolides containing adjacent quaternary and tertiary chiral centers has been presented in excellent stereoselectivities (86-96% ee, dr >95:5) and moderate to good yield (50-83%). Their synthetic utility has been well demonstrated by the facile construction of bicyclic lactones bearing 4-5 stereogenic centers.


Asunto(s)
4-Butirolactona/análogos & derivados , Carbonatos/química , 4-Butirolactona/síntesis química , 4-Butirolactona/química , Alquilación , Compuestos Alílicos/química , Catálisis , Alcaloides de Cinchona/química , Técnicas Químicas Combinatorias , Estructura Molecular , Estereoisomerismo
10.
Yi Chuan Xue Bao ; 32(5): 481-6, 2005 May.
Artículo en Chino | MEDLINE | ID: mdl-16018258

RESUMEN

The mitochondrial DNA (mtDNA) D-loop sequences with 399 bp in 26 individuals from 5 donkey breeds in China were analyzed. Aligned by Clustal W software,the results showed that 23 polymorphic nucleotide sites and only transition with the percentage of 5.76% in 399 bp were observed. In reference to mtDNA D-loop sequences of European domestic donkey as a control, the average percentage of mtDNA D-loop nucleotide variation in 5 Chinese donkey breeds was 1.80%. The average percentages of D-loop nucleotide variation from Liangzhou donkey (LZ), Yunnan donkey (YN), Guanzhong donkey (GZ), Xinjiang donkey (XJ) and Jiami donkey (JM) were 0. 35%, 1.25%, 2.30%, 2.91% and 2.20% respectively. The average sequence divergence estimated from D-loop sequences varied from 0.25% - 5.01% within breeds and 4.51% - 5.51% among breeds, respectively, demonstrating that there existed rather abundant mitochondrial genetic diversity in Chinese donkeys. Comparisons of the 26 sequences revealed 11 mitochondrial haplotypes; the percentage of haplotype was 42.31%. This phenomenon demonstrated that the mitochondrial genetic diversity in Chinese donkey breeds is being reduced. It is urgent to protect the genetic resources of Chinese donkey. The molecular phylogenetic tree of mtDNA D-loop sequences in 5 Chinese donkey breeds,6 sequences of Asian wild ass (Equus asinus kiang, Equus asinus kulan, Equus asinus hemionus;) and 4 sequences of European domestic donkeys from GenBank was constructed by Neighbor-Joining method. It was the first time proved in molecular level that the origin of Chinese donkey breeds was from African wild ass (Equus africanus africanus and Equus africanus somaliensis), not from Asian wild ass as bescribed in the paper.


Asunto(s)
ADN Mitocondrial/genética , Equidae/genética , Haplotipos , Polimorfismo Genético , Animales , Secuencia de Bases , China , Equidae/clasificación , Variación Genética , Filogenia
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