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1.
Plant Mol Biol ; 102(4-5): 389-401, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31894456

RESUMO

KEY MESSAGE: This study revealed that the Arabidopsis UGT75B1 plays an important role in modulating ABA activity by glycosylation when confronting stress environments. The cellular ABA content and activity can be tightly controlled in several ways, one of which is glycosylation by family 1 UDP-glycosyltransferases (UGTs). Previous analysis has shown UGT75B1 activity towards ABA in vitro. However, the biological role of UGT75B1 remains to be elucidated. Here, we characterized the function of UGT75B1 in abiotic stress responses via ABA glycosylation. GUS assay and qRT-PCR indicated that UGT75B1 is significantly upregulated by adverse conditions, such as osmotic stress, salinity and ABA. Overexpression of UGT75B1 in Arabidopsis leads to higher seed germination rates and seedling greening rates upon exposure to salt and osmotic stresses. In contrast, the big UGT75B1 overexpression plants are more sensitive under salt and osmotic stresses. Additionally, the UGT75B1 overexpression plants showed larger stomatal aperture and more water loss under drought condition, which can be explained by lower ABA levels examined in UGT75B1 OE plants in response to water deficit conditions. Consistently, UGT75B1 ectopic expression leads to downregulation of many ABA-responsive genes under stress conditions, including ABI3, ABI5 newly germinated seedlings and RD29A, KIN1, AIL1 in big plants. In summary, our results revealed that the Arabidopsis UGT75B1 plays an important role in coping with abiotic stresses via glycosylation of ABA.

2.
FEBS Open Bio ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901223

RESUMO

Lung adenocarcinoma (LUAD) accounts for ~40% of lung cancer cases, and the 5-year relative survival rate is no more than 1%. Dysregulation of components of striatin-interacting phosphatase and kinase (STRIPAK) complexes is associated with various diseases, including cancer. Striatin-interacting protein 2 (STRIP2), also called Fam40b, has been reported to regulate tumor cell growth and migration. Here, we investigated the role of STRIP2 in LUAD growth, migration and the underlying mechanisms. Analysis of data from The Cancer Genome Atlas database revealed that STRIP2 is highly expressed and predicted poor outcomes in patients with LUAD. Moreover, quantitative RT-PCR (qRT-PCR) analysis revealed that the mRNA expression of STRIP2 is greater in all tested LUAD cells than in a normal lung cell line. To investigate the function of STRIP2, we overexpressed STRIP2 in SPC-A1 cells and depleted STRIP2 in Calu-3 cells. Cell proliferation was evaluated by Cell Counting Kit-8 and colony-forming assays, and Transwell assay was employed to test cell invasion and migration. Our results indicate that STRIP2 depletion suppressed cell proliferation, invasion and migration in Calu-3 cells, and overexpression of STRIP2 had the opposite effects in SPC-A1 cells. Moreover, we discovered that STRIP2 depletion reduced the protein levels of p-Akt and phosphorylated-mammalian target of rapamycin (p-mTOR) in Calu-3 cells, whereas STRIP2 overexpression increased levels of these proteins in SPC-A1 cells. Furthermore, we found that silencing of STRIP2 clearly enhanced protein levels of E-cadherin and reduced levels of N-cadherin, Vimentin and matrix metalloproteinase-9 in Calu-3 cells, whereas overexpression of STRIP2 had the opposite effect in SPC-A1 cells. Our data indicate that STRIP2 promotes the proliferation and motility of LUAD cells, and this may be mediated through the regulation of the Akt/mTOR pathway and epithelial-mesenchymal transition. These results may facilitate the development of therapeutic strategies to treat LUAD.

3.
Environ Res ; 181: 108946, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31780051

RESUMO

BACKGROUND: Longer ambulance response time (ART) delaying treatment would worsen conditions of seriously ill or injured patients, but limited evidence is available on the effects of weather factors on ART. This study aims to assess precipitation- and temperature-ART associations and their potential lagged effects using a novel modeling strategy. METHODS: Based on 779,156 emergency records during 2010-2016 from the whole population in Shenzhen, China, we creatively combined quantile regression with distributed-lag nonlinear models to examine the non-linear and lagged effects of hourly precipitation and temperature on ART at the 50th and 90th percentiles. RESULTS: A linear precipitation-ART association with a delay of 9.01 (95%CI, 7.82-10.20) seconds at median ART for a 1 mm increase in hourly precipitation, and the effects lasted for 5 h with the greatest effect at the current hour. A two linear thresholds temperature-ART association revealed 1 °C decrease below 19 °C caused 1.68 (95%CI, 0.92-2.44) seconds delay in total ART over lag 0-7 h, and 1 °C increase above 24 °C caused 2.44 (95%CI, 1.55-3.33) seconds delay. The hourly call volumes exceeding 54 calls caused 8.79 (95%CI, 8.71-8.86) seconds delay in total ART for 1 more call, but not affected the effects of weather factors. The internal ART suffered more from the hourly call volumes, while the external ART suffered more from precipitation and temperature. The effects were apparently greater on ART at the 90th percentile than median. CONCLUSIONS: Precipitation and temperature are independent risk factors for ambulance services performance, and their lagged effects are notable. The external ART and patients with long ART are vulnerable. More attention should be paid to weather and ART, and these findings may have implications for effective policies to reduce ART to protect public health.

4.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4003-4011, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840444

RESUMO

Nitrogen deposition will affect the morphology of fine roots and its absorption of nutrien-ts, resulting in changes nutrient cycling in terrestrial ecosystems. In order to understand the effects of nitrogen deposition on fine root morphological traits of Castanopsis fabri and C. carlesii, two ectomycorrhizas tree species, we carried out in situ experiment using the root bags method in an evergreen broadleaved forest in the subtropical zone. The results showed that the plastic responses of specific root length and specific root surface area of low-order roots (first to third order) to nitrogen addition was higher than that of high-order roots (fourth order). The plastic responses of root tissue density to nitrogen addition increased from the first-order to the fourth-order, while the average root diameter of each order had no significant plastic responses to nitrogen addition. There was a certain synergistic change between the plastic response of specific root length and specific surface area in the low order fine root and the plastic response of tissue density in the high order fine root. The specific root length, specific root surface area and root tissue density of the two species showed opposite plastic responses to nitrogen addition, indicating that different ectomycorrhizal tree species had different nutrient foraging strategies. C. fabri adopted rapid absorption strategy by increasing specific root length, specific root surface area, and proliferation rate of fine root length, while C. carlesii adopted a relatively conservative resource absorption strategy by increasing tissue density of fine roots.


Assuntos
Ecossistema , Nitrogênio , Florestas , Raízes de Plantas , Plásticos , Árvores
5.
ACS Omega ; 4(19): 18334-18341, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31720535

RESUMO

Here, we report our trials to regulate the luminescence performance of the macrocyclic samarium(III) complex and prepare four excellent luminescent Sm(III) complex-doped poly(methylmethacrylate) (PMMA) composites. Four 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(III) complexes, Sm-2 a -Sm-2 d , originating from dialdehydes with different pendant arms and 1,2-bis(2-aminoethoxy)ethane, have been constructed by the template method. Crystal structures reveal that every Sm(III) ion with the coordination geometry of a distorted bicapped square antiprism is capsulated by the macrocyclic cavity environment forming the "lasso-type" protection. Relative photophysical properties of macrocyclic Sm(III) complexes are carefully investigated in solid-state, methanol solution, and doped PMMA film, and all these show characteristic emissions of the Sm(III) ion associated with satisfactory lifetimes and quantum yields in all media, which could be comparable to reported outstanding examples. Especially, the luminescence performance for this type of Sm(III) complex could be regulated in the solid state by the use of different functional groups in the pendant arm while it is not achieved in solution and the doped PMMA composite. High emitting and air-stable plastic materials could be obtained when these Sm(III) complexes are doped in PMMA with 0.1 wt % mixing ratio, and the corresponding maximum lifetime and quantum yield are 61.2 µs and 0.63% in the case of complex Sm-2 a , respectively. We believe that these highly luminescent "lasso-type" Sm(III) complexes and doped PMMA composites are valuable references in the design of luminescent lanthanide(III) hybrid materials.

7.
Biomater Sci ; 7(12): 5177-5186, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31588463

RESUMO

The development of gene therapy puts forward the requirements for efficient delivery of genetic information into diverse cells. However, in some cases of transfection, especially those for transfecting some primary cells and for delivering large size plasmid DNA (pDNA), the existing conventional transfection methods show poor efficiency. How to further improve transfection efficiency in these hard-to-achieve issues remains a crucial challenge. Here, we report a photothermal-assisted surface-mediated gene delivery based on a polydopamine-polyethylenimine (PDA-PEI) surface. The PDA-PEI surface was prepared through PEI-accelerated dopamine polymerization, which showed efficiency in the immobilization of PEI/pDNA polyplexes and remarkable photothermal properties. Upon IR irradiation, we observed improved transfection efficiencies of two important hard-to-achieve transfection issues, namely the transfection of primary endothelial cells, which are kinds of typical hard-to-transfect cells, and the transfection of cells with large-size pDNA. We demonstrate that the increases of transfection efficiency were due to the hyperthermia-induced pDNA release, the local cell membrane disturbance, and the polyplex internalization. This work highlights the importance of local immobilization and release of pDNA to gene deliveries, showing great potential applications in medical devices in the field of gene therapy.

8.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(8): 801-805, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31416506

RESUMO

OBJECTIVE: To study the clinical effect and safety of clopidogrel combined with aspirin in antithrombotic therapy for children with Kawasaki disease (KD) complicated by coronary artery aneurysm (CAA). METHODS: A total of 77 KD children who were diagnosed with multiple small/medium-sized CAAs by echocardiography between January 2013 and June 2018 were enrolled. They were randomly divided into observation group with 38 children (treated with clopidogrel and aspirin) and control group with 39 children (treated with low-molecular-weight heparin and aspirin). All children were followed up regularly, and the first 3 months of the course of the disease was the observation period. The children were observed in terms of the change of the coronary artery and the incidence of complications. RESULTS: At month 3 of follow-up, among the children in the observation group, 6 had normal coronary artery, 11 had coronary artery retraction, 19 had stable coronary artery, and 2 progressed to giant coronary aneurysm; among the children in the control group, 7 had normal coronary artery, 12 had coronary artery retraction, 19 had stable coronary artery, and 1 progressed to giant coronary aneurysm; there was no significant difference in the change of the coronary artery between the two groups (P>0.05). There were 2 cases of epistaxis and 6 cases of skin ecchymosis in the observation group, and 1 case of epistaxis and 7 cases of petechiae and ecchymosis at the injection site in the control group, and no other serious bleeding events were observed in either group. CONCLUSIONS: Clopidogrel combined with low-dose aspirin is safe and effective in antithrombotic therapy for children with KD complicated by CAA.


Assuntos
Aspirina/uso terapêutico , Aneurisma Coronário , Síndrome de Linfonodos Mucocutâneos , Criança , Clopidogrel , Aneurisma Coronário/tratamento farmacológico , Aneurisma Coronário/etiologia , Vasos Coronários , Fibrinolíticos , Humanos , Síndrome de Linfonodos Mucocutâneos/complicações
9.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2156-2164, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418217

RESUMO

A three-factor experiment with air temperature manipulation, soil temperature manipulation and nutrients distribution pattern was conducted in Forest Ecosystem and Global Change Research Station of Fujian Normal University in Chenda, Sanming, Fujian Province. We examined the effects of heterogeneous distribution of soil resources and warming on underground and aboveground growth of Chinese fir (Cunninghamia lanceolata) seedlings, and whether warming could change the recognition of fine roots to the heterogeneous distribution of soil resources, to understand the response of Chinese fir seedlings to heterogeneous distribution of soil resources under the background of global warming. The results showed that the recognition degree of Chinese fir to the nutrients distribution pattern was mainly reflected by the absorbing root (0-1 mm diameter class) rather than by the 1-2 mm diameter class fine roots. There were no significant effects of warming on the ratio of fine root biomass between nutrient-poor and nutrient-rich patches, the coefficient of nutrients-avoidance and the coefficient of nutrients-preference of fine roots of young Chinese fir except for the single air warming. Chinese fir had higher fine root biomass (0-1 mm diameter class) and lower height in the heterogeneous soil resource environment. Air warming decreased the biomass of fine roots (both 0-1 and 0-2 mm diameter classes) and increased the height of trees. Soil warming decreased the fine root biomass of 1-2 mm diameter class and increased the height of trees and the length of lateral branches. There was no significant interactive effect of air warming, soil warming and heterogeneity of soil resource on aboveground and belowground growth of Chinese fir. The results demonstrated that the absorbing roots of Chinese fir seedlings could recognize the heterogeneous distribution of soil resources,which was not altered by warming.


Assuntos
Cunninghamia , Biomassa , Raízes de Plantas , Plântula , Solo , Árvores
10.
Biotechnol J ; : e1900135, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31464064

RESUMO

Microalgae have long been considered as potential biological feedstock for the production of wide array of bioproducts, such as biofuel feedstock because of their lipid accumulating capability. However, lipid productivity of microalgae is still far below commercial viability. Here, a glucose-6-phosphate dehydrogenase from the oleaginous microalga Nannochloropsis oceanica is identified and heterologously expressed in the green microalga Chlorella pyrenoidosa to characterize its function in the pentose phosphate pathway. It is found that the G6PD enzyme activity toward NADPH production is increased by 2.19-fold in engineered microalgal strains. Lipidomic analysis reveals up to 3.09-fold increase of neutral lipid content in the engineered strains, and lipid yield is gradually increased throughout the cultivation phase and saturated at the stationary phase. Moreover, cellular physiological characteristics including photosynthesis and growth rate are not impaired. Collectively, these results reveal the pivotal role of glucose-6-phosphate dehydrogenase from N. oceanica in NADPH supply, demonstrating that provision of reducing power is crucial for microalgal lipogenesis and can be a potential target for metabolic engineering.

11.
Medicine (Baltimore) ; 98(31): e16680, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31374049

RESUMO

BACKGROUND: Colorectal Adenomatous Polyp (CAP) was one precursor of colorectal cancer (CRC) and having a high chance of developing into CRC. There was a lack of conclusive chemoprevention evidences to prevention new CAP occurrence in post-polypectomy. Xiaoai Jiedu Decoction, Chinese National Medical Professor (Zhou Zhongying)'s experience formula, has been used to treat new CAP occurrence in post-polypectomy from the 20th century in China. However, clinical research of Xiaoai Jiedu Decoction in the treatment of CAP recurrence was lack. We design this study to evaluate the efficacy and safety of Xiaoai Jiedu Decoction in the treatment of new CAP occurrence in post-polypectomy on colonoscopy. METHODS/DESIGN: A randomized, controlled, blind and multicenter trial to evaluate the efficacy and safety of Xiaoai Jiedu Decoction is proposed. CAP patients (after complete polypectomy under colonoscopy) will be randomly assigned into Xiaoai Jiedu Decoction group and Xiaoai Jiedu Decoction mimetic agent group. Patients will receive 6-course treatments and a 2-year follow-up. Follow-up colonoscopy will be anticipated to perform in 1 and 2 years after the baseline examinations. The primary outcome measure is the new CAP occurrence in 1 and 2 years. The secondary outcome measure is the occurrence of advanced adenoma in 1 and 2 years. DISCUSSION: This study will provide objective evidences to evaluate the efficacy and safety of Xiaoai Jiedu Decoction as an adjuvant treatment for new CAP occurrence in post-polypectomy. TRIAL REGISTRATION: NCT03616444.


Assuntos
Pólipos Adenomatosos/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Lesões Pré-Cancerosas/prevenção & controle , Método Duplo-Cego , Humanos , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Analyst ; 144(17): 5254-5260, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31364615

RESUMO

In this paper we report a novel probe based on a luminescent 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(iii) complex Sm-2e, originating from the dialdehyde H2Qe and 1,2-bis(2-aminoethoxy)ethane precursors, which is synthesized by the Sm(iii) ion template method. X-ray structural analyses confirm that each ten-coordinate Sm(iii) center with the coordination geometry of a distorted bicapped square antiprism is fully encapsulated by a flexible macrocyclic ligand H2L2e to form a "lasso-type" architecture, and this architecture could enable efficient energy transfer in various solvents confirmed by long lifetimes (33.5-65.2 µs) and high quantum yields (0.23-0.76%) of the Sm(iii) ion. Simultaneously, complex Sm-2e could serve as a probe for sensing organic solvents. Particularly, this complex probe Sm-2e exhibits a highly selective, rapid and sensitive response to tetrahydrofuran (THF), which is easily distinguished by a large absorption shift, even visible to the naked eye, and complete fluorescence quenching. Moreover, the limit of detection for THF is about 0.20% determined by titration experiments, and good selectivity for THF could still be realized in mixture solvents. Consequently, this colorimetric and "turn off" fluorescent probe Sm-2e could be a valuable candidate as a sensor material for sensing THF which has been rarely reported.


Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Furanos/análise , Colorimetria/métodos , Complexos de Coordenação/síntese química , Fluorescência , Corantes Fluorescentes/síntese química , Limite de Detecção , Samário/química , Bases de Schiff/síntese química , Bases de Schiff/química , Espectrometria de Fluorescência/métodos
13.
Anal Chem ; 91(16): 10366-10370, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31343159

RESUMO

DNA nanomachines have received great interest due to their potential to mimic various natural biomolecular machines. Intracellular pH sensing and imaging are of great significance to understand cellular behaviors and disease diagnostics. In this work, we report the novel molecular switching of a self-assembled 3D DNA triangular prism nanomachine (TPN) for pH sensing and imaging in living cells. The TPN was self-assembled in quantitative yields by hybridization with two DNA triangles and three I-strands (containing i-motif sequences). At acidic conditions, the TPN was compressed due to the I-strand that formed an intramolecular i-tetraplex, which was in between the fluorophores Cy3 and Cy5, resulting in a significant fluorescence resonance energy transfer (FRET) signal. At neutral or weakly alkaline conditions, the TPN adopted an extended state due to the random coil form of the I-strand, leading to spatial separation of the two fluorophores and the FRET being blocked. The TPN was fully reversible and could rapidly respond to the pH changes, entered into living cells automatically via an endocytic pathway, monitored spatiotemporal pH changes during endocytosis, maintained its structural integrity after escape from lysosomes, still had the ability for pH sensing, and also visualized pH fluctuations under varying stimuli in living cells. We foresee that this TPN can become a generic platform for a pH-related cell biology study and in disease diagnostics.

14.
Clin Chim Acta ; 497: 114-119, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31344366

RESUMO

BACKGROUND: Klotho is an anti-aging protein and its increased plasma concentrations were related to good functional outcome of acute ischemic stroke. This study was designed to ascertain the prognostic significance of plasma Klotho in intracerebral hemorrhage. METHODS: Plasma Klotho concentrations in 96 intracerebral hemorrhage patients and 96 healthy controls were quantified. Poor prognosis was defined as modified Rankin scale scores >2 at 90 days. The association of plasma Klotho concentrations with stroke prognosis was assessed using regression model. RESULTS: Patients showed a substantially lower concentration of Klotho than healthy controls (P < .01). Klotho concentrations were highly correlated with National Institutes of Health Stroke Scale scores, Glasgow coma scale scores, intracerebral hemorrhage scores and hematoma volumes (r = -0.426, 0.382, -0.334 and - 0.432). Patients with the highest plasma Klotho concentration were less prone to have poor prognosis at 90 days compared with the lowest quartile (odds ratio, 0.092; 95% confidence interval, 0.015-0.562). Its optimal cutoff value for distinguishing patients at risk of poor prognosis was 345 pg/ml, which yielded a sensitivity value of 0.86 and a specificity value of 0.62. CONCLUSIONS: Decreased plasma Klotho concentrations were associated with increasing severity and poor prognosis significantly, indicating the prognostic role of plasma Klotho in intracerebral hemorrhage.

15.
Int Immunopharmacol ; 74: 105705, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31228814

RESUMO

OBJECTIVE: Surgical site infection (SSI) is a common complication in patients following posterior lumbar spinal surgery. Various laboratory data such as laboratory parameters derived neutrophil/lymphocyte count ratio (NLR), have been applied for the prediction of SSI, but more studies are necessary to evaluate the significance of these indicators. Here, our study aims to investigate the predictive value of total white blood cells (WBCs), count and percentages of neutrophils and leukocytes, NLR, and C-reactive protein (CRP) for surgical site infection (SSI) in patients after posterior lumbar spinal surgery. METHODS: A total of 293 patients who underwent posterior lumbar spinal surgery were enrolled in this study. Each patient's medical history was retrospectively reviewed, and patients were divided into the deep SSI group (n = 13) and the non-SSI group (n = 280). Laboratory data including total WBC, count and percentages of neutrophils and leukocytes, NLR at 1 week before the operation and the 4 and 7 days post-operation, and CRP at 4 and 7 days post-operation were analysed between the SSI and non-SSI groups. Moreover, predictive power and cut-off of NLR for SSI were determined by receiver operating characteristic curve (ROC) results. RESULTS: Data revealed that the medians of NLR were markedly increased in the SSI group as compared to that in non-SSI group at 4 days (p = 0.011) and 7 days (p = 0.047) post-operation. Moreover, the neutrophil percentage was also dramatically increased in the SSI group at both 4 and 7 days post-operation (p = 0.010 and p = 0.030) respectively compared to the non-SSI group. However, no significant difference was observed between the groups 1 week before the operation. ROC results showed that NLR at 4 days (cut-off >5.19; sensitivity: 61.5%; specificity: 77.6%; AUC = 0.708) and 7 days (cut-off >3.85; sensitivity: 69.2%; specificity: 62.7%; AUC = 0.663) post-operation could significantly discriminate the SSI and non-SSI groups. Logistic regression analysis showed that NLR at both post-operative time points (OR = 1.218; p = 0.003 and OR = 1.296; p = 0.048) could be valuable predictors for SSI. CONCLUSION: NLR at 4 and 7 days post-operation are valuable laboratory predictors for SSI in patients with posterior lumbar spinal surgery.

16.
Org Lett ; 21(10): 3808-3812, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31059269

RESUMO

A novel approach to α-amino-α-cyanophosphonates has been developed. The method features a Tf2O-mediated reductive geminal cyanation/phosphonylation of secondary amides. Mild reaction conditions, high bond-forming efficiency, inexpensive readily available starting materials, and good to excellent yields with wide functional group compatibility constitute the main advantages of this method. The protocol can be run on a gram scale.

17.
Brain Res Bull ; 149: 222-230, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31009699

RESUMO

Intracellular mechanical tension plays a vital role in maintaining neuronal function and is generated steerablely by motor proteins along microfilaments (MFs) and microtubules (MTs). To explore the interaction between these subcellular tensions and elucidate their underlying mechanisms, we constructed MF- and MT-dependent tension probes using the Förster resonance energy transfer technique. Hypotonic stress activated MF and MT tensions in calcium-dependent manner, which antagonized outward expansion of cells synergistically; conversely, hypertonic stress attenuated MF and MT tensions in a calcium-independent manner and their interaction is antagonistical. In response to ischemia/hypoxia-related factors, glutamic acid upregulated MF and MT tensions synergistically, similarly to calcium signaling. Energy depletion elicited by ammonium ions increased MT tension, but not MF tension. Oxygen free radical stimulus had no effect on MT and MT tensions. However, MT tension was involved in the antagonism of MF tension in response to energy depletion and oxygen free radicals. Our findings suggest that intracellular MF and MT tensions can interact synergistically or antagonistically in neuronal cells, which is indispensable in ischemia/hypoxia -induced neuron dysfunction.

18.
Environ Health ; 18(1): 38, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-31014345

RESUMO

BACKGROUND: People are exposed to mixtures of highly correlated gaseous, liquid and solid pollutants. However, in previous studies, the assessment of air pollution effects was mainly based on single-pollutant models or was simultaneously included as multiple pollutants in a model. It is essential to develop appropriate methods to accurately estimate the health effects of multiple pollutants in the presence of a high correlation between pollutants. METHODS: The flexible tensor product smooths of multiple pollutants was applied for the first time in a quasi-Poisson model to estimate the health effects of SO2, NO2 and PM10 on daily all-cause deaths during 2005-2012 in Guangzhou, China. The results were compared with those from three other conventional models, including the single-pollutant model and the three-pollutant model with and without first-order interactions. RESULTS: The tensor product model revealed a complex interaction among three pollutants and significant combined effects of PM10, NO2 and SO2, which revealed a 2.53% (95%CI: 1.03-4.01%) increase in mortality associated with an interquartile-range (IQR) increase in the concentrations of all three pollutants. The combined effect estimated by the single-pollutant model was 5.63% (95% CI: 3.96-7.34%). Although the conventional three-pollutant models produced combined effect estimates (2.20, 95%CI, 1.18-3.23%; 2.78, 95%CI: 1.35-4.23%) similar to those of the tensor product model, they distorted the estimates and inflated the variances of the estimates when attributing the combined health effects to individual pollutants. CONCLUSIONS: The single-pollutant model or conventional multi-pollutant model may yield misleading results in the presence of collinearity. The tensor product quasi-Poisson regression provides a novel approach to the assessment of the health impacts of multiple pollutants by flexibly fitting the interaction effects and avoiding the collinearity problem.


Assuntos
Poluentes Atmosféricos/toxicidade , Modelos Teóricos , Idoso , Feminino , Humanos , Masculino , Mortalidade , Dióxido de Nitrogênio/toxicidade , Material Particulado/toxicidade , Análise de Regressão , Medição de Risco , Dióxido de Enxofre/toxicidade
19.
Phytomedicine ; 61: 152848, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31035048

RESUMO

BACKGROUND: 2-hydroxy-3-methylanthraquinone (HMA), an anthraquinone monomer in traditional Chinese medicine Hedyotis diffusa, has been reported to inhibit the growth of several types of cancer, but its effect on lung cancer has not been adequately investigated. HYPOTHESIS/PURPOSE: This study aimed to test the hypothesis that HMA inhibit the growth, migration, and invasion of lung cancer cells in part via downregulation of interleukin (IL)-6-induced JAK2/STAT3 pathway. METHODS: Growth and apoptosis of lung cancer cells were quantitated by CCK-8 assay and Annexin V-FITC/PI flow cytometric analysis, respectively. Migration and invasion of A549 cells were determined by wound-healing assay and transwell invasion assay, respectively. The effect of HMA on cytokines expression in A549 cells was evaluated by the cytokine antibody array assay. Gene expression and protein levels of related molecular markers were quantitated by real time-PCR and Western blot analysis, respectively. RESULTS: HMA significantly inhibited IL-6-stimulated growth and colony formation of A549 cells, increased the number of apoptotic cells, and inhibited invasion associated with downregulation of expression of IL-6-induced MMP-1, MMP-2, and MMP-9 genes. IL-6 increased the levels of tyrosine phosphorylation of JAK2 and STAT3 in A549 cells, which was reversed by HMA treatment. In addition, HMA reduced the expression of a series of inflammation-related cytokines in A549 cells supernatant, including IL-6, G-CSF, IL-6R, IL-8, MCP-1, RANTES, TNF-α. CONCLUSION: These results suggest that HMA may inhibit the growth and invasion of lung cancer cells in part via downregulation of IL-6-induced JAK2/STAT3 pathway.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Janus Quinase 2/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Células A549 , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Medicamentos de Ervas Chinesas/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Neoplasias Pulmonares/patologia , Metaloendopeptidases/genética , Metaloendopeptidases/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Transdução de Sinais/efeitos dos fármacos
20.
Plant Physiol ; 180(4): 2167-2181, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962291

RESUMO

Plant systemic acquired resistance (SAR) provides an efficient broad-spectrum immune response to pathogens. SAR involves mobile signal molecules that are generated by infected tissues and transported to systemic tissues. Methyl salicylate (MeSA), a molecule that can be converted to salicylic acid (SA), is an essential signal for establishing SAR, particularly under a short period of exposure to light after pathogen infection. Thus, the control of MeSA homeostasis is important for an optimal SAR response. Here, we characterized a uridine diphosphate-glycosyltransferase, UGT71C3, in Arabidopsis (Arabidopsis thaliana), which was induced mainly in leaf tissue by pathogens including Pst DC3000/avrRpt2 (Pseudomonas syringae pv tomato strain DC3000 expressing avrRpt2). Biochemical analysis indicated that UGT71C3 exhibited strong enzymatic activity toward MeSA to form MeSA glucosides in vitro and in vivo. After primary pathogen infection by Pst DC3000/avrRpt2, ugt71c3 knockout mutants exhibited more powerful systemic resistance to secondary pathogen infection than that of wild-type plants, whereas systemic resistance in UGT71C3 overexpression lines was compromised. In agreement, after primary infection of local leaves, ugt71c3 knockout mutants accumulated significantly more systemic MeSA and SA than that in wild-type plants. whereas UGT71C3 overexpression lines accumulated less. Our results suggest that MeSA glucosylation by UGT71C3 facilitates negative regulation of the SAR response by modulating homeostasis of MeSA and SA. This study unveils further SAR regulation mechanisms and highlights the role of glucosylation of MeSA and potentially other systemic signals in negatively modulating plant systemic defense.

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