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1.
Tissue Cell ; 84: 102170, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37494831

RESUMO

LPS-induced injury in lung epithelial cells is a crucial part of the process of acute lung injury (ALI). The aim of this study is to explore whether Xanthorrhizol, a medicine that has antioxidant and anti-inflammatory activity, could mitigate the injury of lung epithelial cells caused by LPS. Mouse lung epithelial cell line (MLE-12 cells) were treated with LPS in the absence and presence of Xanthorrhizol. As a results, we observed that LPS could induce MLE-12 cells death, mitochondrial dysfunction, oxidative stress and inflammation, and activate MAPK signaling pathways. However, Xanthorrhizol mitigated the injury in MEL-12 caused by LPS by promoting cell viability and MDA, GSH production as well as inhibiting LDH release, mitochondria damage, IL-1ß, IL-6 and TNF-α production and the phosphorylation levels of ERK, P38 and JNK. Our results indicated that Xanthorrhizol could protect lung epithelial cells from LPS-induced injury, more likely by inhibiting the phosphorylation of MAPK pathway related proteins.


Assuntos
Lipopolissacarídeos , Pulmão , Animais , Camundongos , Lipopolissacarídeos/toxicidade , Lipopolissacarídeos/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Estresse Oxidativo
2.
Immunobiology ; 228(3): 152336, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37173190

RESUMO

R-spondin 3 (Rspo3) is involved in various cellular processes. The alteration of Rspo3 participates in the differentiation of intestinal epithelial cells which are the crucial effector cells during necrotizing enterocolitis (NEC) development. Amniotic fluid stem cells (AFSCs) were recently indicated as a potential approach for NEC therapy. This study aimed to illustrate the regulatory role and mechanism of Rspo3 in the pathogenesis of NEC and whether AFSCs therapy would impact NEC by mediating Rspo3. First, the alteration of Rspo3 was investigated in the serum and tissues of NEC patients, and an in vitro cell model induced by LPS. A gain-of-function assay was conducted to explore the function of Rspo3 in NEC. Through the analysis of adenosine 5'-monophosphate-activated protein kinase α (AMPKα) activation, the mechanism of Rspo3-mediated NEC progression was demonstrated. Finally, AFSCs were used to coculture human intestinal epithelial cells (HIECs) and the impacts on NEC development were also explored. The results found that Rspo3 was dramatically depressed during NEC progression and reversing Rspo3 expression ameliorated LPS-induced injury, inflammation, oxidative stress and tight junction dysregulation in HIECs. Besides, Rspo3 overexpression reversed AMPKα inactivation induced by NEC and an AMPKα inhibitor, Compound C, blocked the effect of Rspo3 overexpression on NEC. AFSCs treatment was beneficial for NEC therapy by restoring Rspo3 expression which was counteracted by exosome inhibitor. Generally, AFSCs attenuated NEC progression by promoting the Rspo3/AMPKα axis which might exert via the secretion of exosomes. Our conclusions might be valuable for NEC diagnosis and therapy.


Assuntos
Enterocolite Necrosante , Humanos , Líquido Amniótico/metabolismo , Enterocolite Necrosante/etiologia , Mucosa Intestinal/metabolismo , Intestinos , Lipopolissacarídeos/metabolismo , Células-Tronco/metabolismo , Células-Tronco/patologia , Proteínas Quinases Ativadas por AMP
3.
Hum Exp Toxicol ; 41: 9603271221099589, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35607288

RESUMO

CLINICAL RELEVANCE: MicroRNAs (miRNAs) have been reported to be involved in the progression of various diseases. Studying the regulatory mechanisms of miRNAs can help clinical treatment. BACKGROUND: Diabetic retinopathy (DR) is one of the complications of diabetes. The objective of this study was to elucidate the underlying molecular mechanisms by which miR-200c-3p regulates the pyroptosis of DR cell. METHODS: Human retinal microvascular endothelial cells (HRMECs) and high glucose (HG) cultures established DR cell model in vitro. RT-qPCR is used to detect the expression level of miRNAs. CCK-8 assays and flow cytometry are used to detect apoptosis of HRMECs cell. Western blotting is used to detect cleaved caspase-3, cleaved caspase-1, and N-GSDMD proteins levels in HRMECs. The ELISA assay is used to detect the expression of IL-1ß and IL-18. Predict and validate potential binding sites between miR-200c-3p and SLC30A7 by dual luciferase reporter gene analysis. RESULTS: The results showed that HG caused damage to HRMECs through the pyroptosis pathway rather than the apoptosis pathway. MiR-200c-3p is highly expressed in HG induced-HRMECs, and knockdown of miR-200c-3p mitigates HG-induced HRMECs pyroptosis. MiR-200c-3p negatively targets SLC30A7 in HRMECs, and miR-200c-3p regulates pyroptosis of HG-induced HRMECs by targeting SLC30A7. CONCLUSION: The results suggest that miR-200c-3p might be a promising interference target for DR prevention and treatment. The results of current study may provide new insights into development of therapeutic strategies for DR.


Assuntos
Proteínas de Transporte de Cátions , Diabetes Mellitus , Retinopatia Diabética , MicroRNAs , Apoptose/genética , Proteínas de Transporte de Cátions/genética , Diabetes Mellitus/metabolismo , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Células Endoteliais/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Piroptose/fisiologia
4.
Fetal Pediatr Pathol ; 41(3): 499-504, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33213248

RESUMO

Background: Extraskeletal Ewing's Sarcoma (EES) may harbor more than one tumor-specific genetic abnormality, leading to diagnostic difficulties. Case report: We report a nine-year-old boy with recurrent mass of his right thigh. Tumor cells were round, with scant cytoplasm, finely dispersed chromatin, and inapparent, small nucleoli. The initial misdiagnosis was T-lymphoblastic lymphoma due to CD7 and TCR/Ig monoclonal rearrangement. As it expressed NKX2.2 and harbored an EWSR1-FLI1 fusion transcript, the diagnosis was changed to EES. The child underwent EES therapy with good initial response, but had a subcutaneous relapse at 22 months. Conclusion: In addition to typical genetic alterations, Ewing sarcoma can also express CD7 and TCR/Ig rearrangement, which are not limited to lymphoma.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Sarcoma de Ewing , Criança , Humanos , Imunoglobulinas , Masculino , Recidiva Local de Neoplasia , Receptores de Antígenos de Linfócitos T , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia
5.
Chemistry ; 27(42): 10898-10902, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33780036

RESUMO

Anthrathiadiazole is a key synthon for the construction of large azaacenes, however, the attachment of different substituents onto the skeleton of anthrathiadiazole is difficult but highly desirable because it could be easy to enrich the structures of azaacenes. Here, it is demonstrated that anthrathiadiazole derivatives with -Br, -CN, and -OCH3 groups could be easily constructed through a simple [4+2] cycloaddition reaction between a,a,a',a'-tetrabromo-o-xylenes derivatives and benzo[c][1,2,5]thiadiazole-4,7-dione. The structures of the as-prepared compounds with different substituents were carefully characterized. Moreover, the basic physical properties of the as-prepared anthrathiadiazole derivatives were fully investigated, where the cyano-substituted derivative (BTH-CN) has the highest stability and the methoxy-substituted derivative (BTH-OCH3 ) is easy to be oxidized. Moreover, the two-photon absorption (TPA) characteristics of different anthrathiadiazoles are also studied by using the femtosecond Z-scan technique. The results show that the fused anthrathiadiazole skeletons possess large TPA cross-section values δ2 in the range of 3000-5000 GM, where the nature, position and strength of the substituted groups have strong effect on these values.

6.
PLoS One ; 16(2): e0247339, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33621234

RESUMO

The vertical stratification of the stand may lead to a high heterogeneity of microenvironment in the forest, which further influences the understory regeneration and succession of the forest. Most relevant previous studies emphasized the overall effects of the Whole-stand structural characteristics on understory regeneration, while the strata-specific impacts of the overstory should be explored especially for those forests with a complicated combination of overstory species and heights. In this study, a subtropical evergreen broad-leaved forest in Tianmu Mountain of China was intensively investigated within 25 plots of 20 m × 20 m, aiming to find out how significant the stratified overstory (trees with diameter at breast height (DBH) ≥ 5 cm) structure and non-structure characteristics impact the understory (trees with DBH < 5 cm) regeneration. Regardless of species composition, the studied overstory was evenly divided into three strata (i.e. upper, middle and lower strata) according to their heights. Redundancy analysis was applied to explore both overall and strata-specific forest structure on characteristics (height, DBH, species diversity, and density) of tree regeneration. We found that the overall effect of the whole overstory on the forest regeneration depended mostly on diameter at breast height (DBH), tree species richness index and crown width. However, when analyzing with the strata-specific characteristics, the most pronounced impact factors for the regeneration were tree height of the upper and lower forest strata, tree species richness index and crown width of the middle and lower forest strata, and the competition index impact of the lower forest stratum. Among the three strata, the lower forest stratum showed the most significant impact with three characteristics on the understory regeneration, which may be attributed to their direct competition within the overlapping near-ground niches. Among the new generations, seedlings and saplings were more sensitive to the overstory structural characteristics than young trees. Our results suggest that the overstory showed strata-specific effects on the understory regeneration of evergreen broad-leaved forests in subtropical China, which provides theoretical basis for strata-specific forest management in similar forests.


Assuntos
Conservação dos Recursos Naturais/métodos , Plântula/crescimento & desenvolvimento , China , Ecossistema , Florestas
8.
Front Plant Sci ; 11: 591852, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343597

RESUMO

Phytolith-occluded carbon (PhytOC), a promising long-term biogeochemical carbon sequestration mode, plays a crucial role in the global carbon cycle and the regulation of atmospheric CO2. Previous studies mostly focused on the estimation of the content and storage of PhytOC, while it remains unclear about how the management practices affect the PhytOC content and whether it varies with stand age. Moso bamboo (Phyllostachys heterocycla var. pubescens) has a great potential in carbon sequestration and is rich in PhytOC. Here, we selected four management treatments, including control (CK), compound fertilization (CF), silicon (Si) fertilization (SiF) (monosilicic acid can form phytoliths through silicification), and cut to investigate the variation of phytoliths and PhytOC contents in soil, leaves, and litters, and their storage in Moso bamboo forests. In soil, the SiF fertilizer treatment significantly (P < 0.05) increased phytolith content, PhytOC content, and storage compared to CK, while there were no significant differences between the treatments of CF and cut. In leaf, compared with CK, phytolith content of the second-degree leaves under SiF and the first-degree leaves under cut treatment significantly increased, and the three treatments significantly increased PhytOC storage for leaves with three age classes. In litter, the phytolith and PhytOC contents under the three treatments were not significantly different from that under the CK treatment. The PhytOC storage increased by 19.33% under SiF treatment, but significantly decreased by 40.63% under the CF treatment. For the entire Moso bamboo forest ecosystems, PhytOC storage of all the three management treatments increased compared with CK, with the largest increase by 102% under the SiF treatment. The effects of management practices on the accumulation of PhytOC varied with age. Our study implied that Si fertilization has a greater potential to significantly promote the capacity of sequestration of carbon in Moso bamboo forests.

9.
Pestic Biochem Physiol ; 167: 104584, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527419

RESUMO

Recently, photodynamic therapy (PDT) and photoactivated pesticides have attracted considerable research attention. In the present study, we aimed to investigate the photodynamic activity of a chlorophyllous derivative, sodium pheophorbide a (SPA), and to evaluate its potential as a photoactivated fungicide. The singlet oxygen quantum yield, the photoreaction process, the anti-photobleaching ability in sterile water (H2O), the effect of light conditions on its antifungal activity, and its stability were all investigated. SPA showed significant fungicidal activity and photostability, during which Type I and Type II photodynamic reactions occurred simultaneously on Pestalotiopsis neglecta, and the influence of Type I was slightly larger than that of Type II. In addition, light promoted the antifungal activity of SPA. In particular, the antifungal activity was enhanced with increasing light intensity, and was strongest under 8000 lx conditions. Under monochromatic light sources, antifungal activity was strongest under green light s; however, the effect of monochromatic light was not as good as that of white light. From 0 to 24 h, the antifungal effect of the SPA solution was enhanced; however, the activity of the solution began to weaken after 24 h. Furthermore, our study confirmed that the antifungal activity of SPA was stable under different temperatures, pH values, and UV irradiation durations.


Assuntos
Fotoquimioterapia , Sódio , Antifúngicos , Clorofila/análogos & derivados , Fármacos Fotossensibilizantes
10.
Sci Total Environ ; 729: 138949, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32387772

RESUMO

Moso bamboo (Phyllostachys Pubescens) forests exhibit a great potential to sequestrate carbon dioxide from atmosphere and to mitigate global climate change. However, they were increasingly under abandoned (i.e., no fertilization, the low intensity and frequency of felling and bamboo shoot digging) due to decreasing economic values of bamboo-related products and increasing labor cost. So far, the changes in soil carbon (C) and nitrogen (N) pools in bamboo forests following abandonment are poorly addressed. In this study, Moso bamboo stands under intensively management and abandonment for different durations were sampled to explore the C and N pool dynamics at the top 40 cm soil. We classified abandonment durations into three categories: discarded or abandoned management for 1-6 years (DM-I), 7-12 years (DM-II) and 13-18 years (DM-III). Our results indicated that (1) soil organic carbon (SOC) storage was significantly increased with abandonment management compared with intensive management (Control, CK), but the durations of abandonment management had no significant effects on SOC. Microbial biomass carbon (MBC) concentration increased from DM-I to DM-III in the 0-40 cm soil layer (P < 0.01), and water-soluble organic carbon (WSOC) concentration decreased through DM-I (P < 0.01). (2) Abandonment management did not significantly affect soil total nitrogen (TN) storage at depth of 0-40 cm, with 9.54 Mg ha-1 for CK, 9.59 Mg ha-1 for DM-I, 9.89 Mg ha-1 for DM-II and 9.69 Mg ha-1 for DM-III. Water-soluble organic nitrogen (WSON) concentration significantly decreased from CK to DM-III. Ammonium nitrogen (NH4+-N) concentration increased from DM-I to DM-III (P < 0.01), and nitrate nitrogen (NO3--N) concentration decreased from CK to DM-III (P < 0.01). The results of the effects of abandonment durations on soil properties in Moso bamboo forests provide valuable information for forest restoration and management.


Assuntos
Florestas , Solo , Biomassa , China , Nitrogênio , Poaceae
11.
BMJ Open ; 9(5): e024932, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31076468

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of removing blood stasis (RBS) herbal medicine for the treatment of acute intracerebral haemorrhage (AICH) within a 6-hour time window. STUDY DESIGN: A randomised, multicentre, double-blind, placebo-controlled study performed in 14 hospitals in China. PARTICIPANTS AND INTERVENTIONS: Patients with AICH were randomly assigned to receive a placebo, the ICH-1 (Intracerebral Haemorrhage) formula (eight herbs, including the RBS herbs hirudo and tabanus) or the ICH-2 formula (six herbs without the RBS herbs hirudo and tabanus) within 6 hours of ICH onset. OUTCOMES: The primary safety outcome was the incidence of haematoma enlargement at 24 hours and at 10 days after treatment. The secondary outcome was the incidence of poor prognosis (mortality or modified Rankin Scale score ≥5) assessed at 90 days after symptom onset. RESULTS: A total of 324 subjects were randomised between October 2013 and May 2016: 105 patients received placebo; 108 patients received the ICH-1 formula; and 111 patients received the ICH-2 formula. The incidence of haematoma enlargement at 24 hours was 7.8% in the placebo group, 12.3% in the ICH-1 group and 7.5% in the ICH-2 group; the incidence of haematoma enlargement on day 10 was 1.1% in the placebo group, 1.1% in the ICH-1 group, and 3.1% in the ICH-2 group, with no significant differences among the groups (P>0.05). The mortality rates were 3.8% in the placebo group, 2.8% in the ICH-1 group, and 0.9% in the ICH-2 group; the incidences of poor prognosis were 7.1% in the placebo group, 6.0% in the ICH-1 group and 4.8% in the ICH-2 group at 3 months, with no significant differences among the groups (p>0.05). However, the overall frequency of treatment-emergent adverse events in the ICH-1 group (12.1%) was higher among the three groups (5.8% and 2.8%, respectively, p<0.05). All three cases of serious adverse events were in the ICH-1 group. CONCLUSIONS: Ultra-early administration of ICH-1 formula for AICH patients did not exert significant beneficial effects on clinical outcomes but increased the risk of bleeding, which probably resulted from the inclusion of RBS herbal medicines in ICH-1. TRIALREGISTRATION NUMBER: NCT01918722.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Hemorragia Cerebral , Medicamentos de Ervas Chinesas , Hematoma , Hemorragia , Fitoterapia , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/tratamento farmacológico , Hemorragia Cerebral/mortalidade , China , Método Duplo-Cego , Monitoramento de Medicamentos/métodos , Monitoramento de Medicamentos/estatística & dados numéricos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Medicamentos de Ervas Chinesas/classificação , Feminino , Hematoma/diagnóstico , Hematoma/etiologia , Hematoma/prevenção & controle , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mortalidade , Fitoterapia/efeitos adversos , Fitoterapia/métodos , Tempo para o Tratamento , Resultado do Tratamento
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-750793

RESUMO

Objective@#To explore the inhibitory effect and possible mechanism of Baicalin on the human tongue squamous cell carcinoma cell line SCC15 and to provide a new idea and experimental basis for the clinical prevention and treatment of tongue squamous cell carcinoma.@*Methods @#SCC15 cells cultured in DMEM alone were used as the control group, and SCC15 cells cultured in 20 mg/mL baicalin solution were used as the baicalin group. Scratch tests and Transwell migration tests were performed to detect changes in cell migration ability, and flow cytometry was used to detect changes in the cell cycle. Western blotting was used to detect differences in the phosphorylation levels of signal transduction and transcription activator 3 (STAT3).@*Results @# Compared with the control group, the scratch test and the Transwell migration test showed that the cell migration ability of cells in the baicalin group was significantly decreased (t=4.927, P=0.008); flow cytometry showed that the number of cells of the baicalin group increased in the G0/G1 phase (t=9.893, P=0.001), decreased in the S phase (t=8.528, P=0.001), and decreased in the G2/M phase (t=3.550, P=0.024); Western blotting results showed that the STAT3 protein of SCC15 cells in the baicalin group decreased (t=3.550, P=0.024), and the phosphorylation level significantly decreased (t=8.262, P=0.001).@*Conclusion @#Baicalin inhibits the human tongue squamous cell carcinoma cell line SCC15, and its mechanism may be related to a decrease in STAT3 pathway phosphorylation activity.

13.
Cell Immunol ; 334: 31-37, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30153899

RESUMO

It has recently been recognized that a subset of asthma patients suffer from glucocorticoid (GC) insensitivity, and glucocorticoid receptor-ß (GR-ß) is associated with corticosteroid resistance, but the underlying mechanisms remain unknown. Here we demonstrated that Interleukin-17A induced glucocorticoid sensitivity in human bronchial epithelial cells (16HBE) is enhanced, which is depend on E4 promoter-binding protein 4 (E4BP4) mediated GR-ß expression. Our data show that the expression of E4BP4 is significantly up-regulated in 16HBE cells, and the depletion of E4BP4 dramatically decreased glucocorticoid sensitivity in IL-17A induced 16HBE cells. Mechanistic studies revealed that E4BP4 plays a crucial role in Interleukin-17A induced glucocorticoid sensitivity in 16HBE cells via down-regulating GR-ß, which is probably mediated by PI3K/Akt activation. Collectively, we can draw the conclusion that E4BP4 contribute to enhance the GCs sensitivity, which may offer a new strategy for therapeutic intervention for GC-insensitive asthma.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Brônquios/metabolismo , Regulação para Baixo/fisiologia , Glucocorticoides/metabolismo , Receptores de Glucocorticoides/metabolismo , Asma/metabolismo , Células Cultivadas , Células Epiteliais , Humanos , Interleucina-17/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima/fisiologia
14.
Proc Natl Acad Sci U S A ; 115(15): 3882-3887, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-29581283

RESUMO

We conducted a model-based assessment of changes in permafrost area and carbon storage for simulations driven by RCP4.5 and RCP8.5 projections between 2010 and 2299 for the northern permafrost region. All models simulating carbon represented soil with depth, a critical structural feature needed to represent the permafrost carbon-climate feedback, but that is not a universal feature of all climate models. Between 2010 and 2299, simulations indicated losses of permafrost between 3 and 5 million km2 for the RCP4.5 climate and between 6 and 16 million km2 for the RCP8.5 climate. For the RCP4.5 projection, cumulative change in soil carbon varied between 66-Pg C (1015-g carbon) loss to 70-Pg C gain. For the RCP8.5 projection, losses in soil carbon varied between 74 and 652 Pg C (mean loss, 341 Pg C). For the RCP4.5 projection, gains in vegetation carbon were largely responsible for the overall projected net gains in ecosystem carbon by 2299 (8- to 244-Pg C gains). In contrast, for the RCP8.5 projection, gains in vegetation carbon were not great enough to compensate for the losses of carbon projected by four of the five models; changes in ecosystem carbon ranged from a 641-Pg C loss to a 167-Pg C gain (mean, 208-Pg C loss). The models indicate that substantial net losses of ecosystem carbon would not occur until after 2100. This assessment suggests that effective mitigation efforts during the remainder of this century could attenuate the negative consequences of the permafrost carbon-climate feedback.

15.
Glob Chang Biol ; 24(5): 1919-1934, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29345031

RESUMO

Amazon droughts have impacted regional ecosystem functioning as well as global carbon cycling. The severe dry-season droughts in 2005 and 2010, driven by Atlantic sea surface temperature (SST) anomaly, have been widely investigated in terms of drought severity and impacts on ecosystems. Although the influence of Pacific SST anomaly on wet-season precipitation has been well recognized, it remains uncertain to what extent the droughts driven by Pacific SST anomaly could affect forest greenness and photosynthesis in the Amazon. Here, we examined the monthly and annual dynamics of forest greenness and photosynthetic capacity when Amazon ecosystems experienced an extreme drought in 2015/2016 driven by a strong El Niño event. We found that the drought during August 2015-July 2016 was one of the two most severe meteorological droughts since 1901. Due to the enhanced solar radiation during this drought, overall forest greenness showed a small increase, and 21.6% of forests even greened up (greenness index anomaly ≥1 standard deviation). In contrast, solar-induced chlorophyll fluorescence (SIF), an indicator of vegetation photosynthetic capacity, showed a significant decrease. Responses of forest greenness and photosynthesis decoupled during this drought, indicating that forest photosynthesis could still be suppressed regardless of the variation in canopy greenness. If future El Niño frequency increases as projected by earth system models, droughts would result in persistent reduction in Amazon forest productivity, substantial changes in tree composition, and considerable carbon emissions from Amazon.


Assuntos
Secas , Florestas , Carbono , El Niño Oscilação Sul , Fotossíntese , Estações do Ano , Luz Solar , Temperatura , Árvores
16.
Sci Rep ; 7(1): 5349, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28706271

RESUMO

Expression profiles of cancer are generally composed of three dimensions including gene probes, patients (e.g., metastasis or non-metastasis) and tissues (i.e., cancer or normal cells of a patient). In order to combine these three dimensions, we proposed a joint covariate detection that not only considered projections on gene probes and tissues simultaneously, but also concentrated on distinguishing patients into different groups. Due to highly lethal malignancy of hepatocellular carcinoma, we chose data GSE6857 to testify the effectiveness of our method. A bootstrap and accumulation strategy was introduced in, which could select candidate microRNAs to distinguish metastasis from non-metastasis patient group. Two pairs of microRNAs were further selected. Each component of either significant microRNA pair was derived from different cliques. Targets were sought and pathway analysis were made, which might reveal the mechanism of venous metastasis in primary hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , MicroRNAs/metabolismo , Biologia Computacional , Perfilação da Expressão Gênica , Humanos
17.
Sci Rep ; 7(1): 2783, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28584271

RESUMO

In order to investigate the effects of N deposition on soil biochemistry in secondary forests, one N addition experiment was conducted in a secondary evergreen broad-leaved forest in the western edge of Sichuan Basin, with the highest level of background N deposition (about 95 kg N ha-1 yr-1) in China. Three N treatment levels (+0, +50, +150 kg N ha-1 yr-1) were monthly added to soil surface in this forest beginning in April 2013. Soil biochemistry and root biomass of the 0-10 cm soil horizon were measured from May 2014 to April 2015. Soil respiration was measured for two years (September 2013 to August 2015). It was showed that N additions were correlated to significantly lower soil pH, microbial biomass C (MBC) concentration, MBC/microbial biomass N (MBN) ratio, root biomass, and soil respiration rate, and significantly higher concentrations of ammonium (NH4+) and nitrate (NO3-). These results indicate that N additions had a significant effect on the size of soil microbial community. In addition, soil C storage may potentially increase due to the dropped soil C release under N addition.

18.
Sci Total Environ ; 593-594: 449-461, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28351812

RESUMO

Snow cover dynamics are considered to play a key role on spring phenological shifts in the high-latitude, so investigating responses of spring phenology to snow cover dynamics is becoming an increasingly important way to identify and predict global ecosystem dynamics. In this study, we quantified the temporal trends and spatial variations of spring phenology and snow cover across the Tibetan Plateau by calibrating and analyzing time series of the NOAA AVHRR-derived normalized difference vegetation index (NDVI) during 1983-2012. We also examined how snow cover dynamics affect the spatio-temporal pattern of spring alpine vegetation phenology over the plateau. Our results indicated that 52.21% of the plateau experienced a significant advancing trend in the beginning of vegetation growing season (BGS) and 34.30% exhibited a delaying trend. Accordingly, the snow cover duration days (SCD) and snow cover melt date (SCM) showed similar patterns with a decreasing trend in the west and an increasing trend in the southeast, but the start date of snow cover (SCS) showed an opposite pattern. Meanwhile, the spatial patterns of the BGS, SCD, SCS and SCM varied in accordance with the gradients of temperature, precipitation and topography across the plateau. The response relationship of spring phenology to snow cover dynamics varied within different climate, terrain and alpine plant community zones, and the spatio-temporal response patterns were primarily controlled by the long-term local heat-water conditions and topographic conditions. Moreover, temperature and precipitation played a profound impact on diverse responses of spring phenology to snow cover dynamics.


Assuntos
Ecossistema , Desenvolvimento Vegetal , Estações do Ano , Neve , China , Análise Espaço-Temporal , Temperatura , Tibet
19.
Chin Med Sci J ; 32(4): 232-238, 2017 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-29301598

RESUMO

Objective The aim of this study was to investigate the relationship between peripheral plasma stem cell factor (SCF)/c-kit levels and the types of dipper and non-dipper hypertension in hypertensive patients. Methods This cross-sectional study included newly diagnosed hypertensive patients who underwent 24-hour ambulatory blood pressure monitor (ABPM) between January 2009 and 2012 in Jiangning city. Patients were divided into the dipper group and the non-dipper group according to ABPM measurements. The levels of SCF and its receptor c-kit, tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) in peripheral blood were measured via enzyme-linked immunosorbent assays. The serum levels of glucose and lipid were examined as well. The levels of SCF/c-kit were compared between the dippers and the non-dippers; and their correlation with 24-hour mean systolic blood pressure (MSBP), 24-hour mean diastolic blood pressure (MDBP), TNF-α and IL-6 were investigated using linear regression analyses statistically. Results A total of 247 patients with newly diagnosed hypertension were recruited into the study, including 116 non-dippers and 131 dippers. The levels of peripheral plasma SCF were higher in non-dipper group (907.1±52.7 ng/L vs. 778.7±44.6 ng/L; t=2.837, P<0.01), and the levels of c-kit were higher in non-dipper group too (13.2±1.7 µg/L vs 9.57±1.4 µg/L; t=2.831, P<0.01). Linear regression analysis revealed that SCF/c-kit levels were significantly positively correlated with MSBP, MDBP, plasma TNF-α, and IL-6 levels (all P<0.01). Conclusions Peripheral plasma SCF/c-kit levels are higher in patients with non-dipper hypertension than those with dipper one, and significantly correlate with 24-hour MSBP, 24-hour MDBP, serum TNF-α and IL-6 levels.


Assuntos
Pressão Sanguínea , Hipertensão/sangue , Fator de Células-Tronco/sangue , Adulto , Idoso , Feminino , Humanos , Hipertensão/fisiopatologia , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue
20.
Sci Total Environ ; 566-567: 627-640, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27236628

RESUMO

Due to rapid urbanization, industrialization and population growth, wetland area in China has shrunk rapidly and many wetland ecosystems have been reported to degrade during recent decades. Wetland health assessment could raise the public awareness of the wetland condition and guide policy makers to make reasonable and sustainable policies or strategies to protect and restore wetland ecosystems. This study assessed the health levels of wetland ecosystem at the Hangzhou Bay, China using the pressure-state-response (PSR) model through synthesizing remote sensing and statistical data. Ten ecological and social-economic indicators were selected to build the wetland health assessment system. Weights of these indicators and PSR model components as well as the normalized wetland health score were assigned and calculated based on the analytic hierarchy process (AHP) method. We analyzed the spatio-temporal changes in wetland ecosystem health status during the past 20years (1990-2010) from the perspectives of ecosystem pressure, state and response. The results showed that the overall wetland health score was in a fair health level, but displayed large spatial variability in 2010. The wetland health score declined from good health level to fair health level from 1990 to 2000, then restored slightly from 2000 to 2010. Overall, wetland health levels showed a decline from 1990 to 2010 for most administrative units. The temporal change patterns in wetland ecosystem health varied significantly among administrative units. Our results could help to clarify the administrative responsibilities and obligations and provide scientific guides not only for wetland protection but also for restoration and city development planning at the Hangzhou Bay area.

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