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1.
Chin Med J (Engl) ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32044815

RESUMO

BACKGROUND: After neoadjuvant chemotherapy (NAC), non-pathological complete response of breast cancer patients can benefit from tailored adjuvant chemotherapy. However, it is difficult to select patients with poorer prognosis for additional adjuvant chemotherapy to maximize the benefits. Our study aimed to explore whether the subtypes of tumor-infiltrating lymphocytes (TILs) in residual tumors (RT) is related to the prognosis of triple-negative breast cancer (TNBC) after NAC. METHODS: Data from patients with primary TNBC consecutively diagnosed at the Breast Disease Center of Peking University First Hospital from 2008 to 2014 were retrieved, and the cases with RT in the breast after NAC were enrolled. TILs subtypes in RT were observed by double-staining immunohistochemistry, and counted with the median TILs value per square millimeter as the cut-off to define high versus low TILs density in each subtype. The relationships between the TIL density of each subgroup and the clinicopathological characteristics of the RT after NAC patients were analyzed by Fisher exact test. Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method and log-rank statistics. RESULTS: A total of 37 eligible patients were included in this study, and the median follow-up period was 50 months (range 17-106 months). There was no significant correlation between the infiltrate density of CD4, CD8, CD20, and CD68 lymphocytes and clinic-pathological characteristics. Significantly better prognosis was observed in patients with high CD4-TILs (DFS: P = 0.005, OS: P = 0.021) and high CD8-TILs (DFS: P = 0.018) and low CD20-TILs (OS: P = 0.042). Further analysis showed that patients with CD4/CD20 ratio greater than 1 (DFS: P = 0.001, OS: P = 0.002) or CD8/CD20 ratio greater than 1 (DFS: P = 0.009, OS: P = 0.022) had a better prognosis. CONCLUSIONS: Subtypes of TILs in RT is a potential predictive biomarker of survival in TNBC patients after NAC.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32030593

RESUMO

Environmental innovation is an important way to low-carbon economic growth. Outward foreign direct investment (OFDI) can produce reverse technology transfer to promote innovation. This study aims to examine whether OFDI to developed countries can transfer reverse green technology and promote the environmental innovation of manufacturing enterprises in emerging economies (EEs). Based on the technology gap theory, resource bricolage theory, resource-based view, and Potter hypothesis, this study constructs a conceptual model including the direct effect of OFDI on environmental innovation and the moderating effects of the knowledge level of the host country, multinational strategy, absorptive capacity, and environmental regulation. To verify the model, we also use a panel dataset of 424 Chinese manufacturing enterprises during 2010-2017, and the results indicate that OFDI to developed countries can produce reverse green technology transfer and promote parent companies' environmental innovation. The knowledge level of the host country and multinational strategy can further improve the impacts on environmental product innovation. However, absorptive capacity and environmental regulation in EEs do not play a significant moderating role. Consequently, this study expands the application scope of existing theories and enriches the theoretical basis of the relationship between OFDI and environmental innovation.

3.
ACS Nano ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32057223

RESUMO

As one of the major air pollutants, NOX is rather challenging to remove. The main treatment method is catalytic reduction with plenty of reducing agents, which lacks any effective control in an open air environment such as urban spaces. It is necessary to seek a self-powered electrochemical process for environmental treatment. The triboelectric nanogenerator (TENG), a developing technology with various advantages, is widely used in energy and environmental monitoring and cleaning. In this work, a radial-engine-shaped TENG system with five stacked TENGs is designed to synchronously absorb NOX and degrade its main enrichment forms of nitrate and nitrite in aqueous solution. In addition, the system possesses inherent phase differences and outputs continuous direct current after rectification. Moreover, we demonstrated that, driven by artificial wind at a speed of 6 m/s, the NOX generated by a chemical method was effectively degraded by the radial-engine-shaped TENG system.

4.
Clin Sci (Lond) ; 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32091078

RESUMO

Sphingolipids have been implicated in the etiology of atherosclerosis. The commonly used sphingolipid inhibitors, myriocin (a ceramide inhibitor) and D-PDMP (a glycosphingolipid inhibitor), have shown therapeutic potential but their efficacy and their underlying mechanisms remain unclear. Here, apoE-/- mice were fed a high-fat diet and treated with a control, myriocin, D-PDMP, or atorvastatin for 12 weeks. We analyzed the effects of these drugs on the size and detailed composition of atherosclerotic plaques. Molecular biological approaches were used to explore how the inhibitors affect lipid metabolism and foam-cell formation. Treatment with myriocin or D-PDMP led to smaller and less vulnerable atherosclerotic lesions and was almost as effective as atorvastatin. Sphingolipid inhibitors downregulated the expression of MCP-1 and its receptor CCR2, which play a key role in monocyte recruitment. They also decreased pro-inflammatory Ly-6chighmonocytes and influenced the uptake of modified LDL by downregulating the expression of CD36 and LOX-1. The inhibitors exhibited the advantage of maintaining normal glucose homeostasis compared with atorvastatin. These findings reveal for the first time that the modulation of sphingolipid synthesis can effectively alleviate atherosclerosis progression by preventing lipid uptake and reducing inflammatory responses in the arterial walls.

5.
Behav Processes ; : 104087, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32088295

RESUMO

Tracking variation in hosts' responses to parasitism across space in a metapopulation is critical to assess the current status of parasitism/anti-parasitism in a host-parasite system, which is also helpful to infer its coevolutionary history. The barn swallow Hirundo rustica is a tractable bird species to understand potential fine-tuned adaptations to avian brood parasitism across small geographic scales, both in the context of variation in its foreign-egg rejection pattern, and its widespread distribution in cuckoo-free urban areas and in cuckoo-present rural habitats, including reedbeds. Here we tested whether variation in co-occurrence between the host and its rare brood parasite, the common cuckoo Cuculus canorus (i.e., high level of co-occurrence in reed habitats, low in town habitats) at the metapopulation level predicts patterns of antiparasitic egg rejection behaviors in barn swallows in response to different types of model and natural eggs. Contrary to our predictions, higher parasite detectability in the reed habitat did not translate into higher parasitism rate in the reed habitat and, in turn, we also found similarly low egg rejection rates across both sampled habitat types. These patterns implied a lack of fine-tuned increase of egg rejection rate in the reed-breeding population of barn swallows as a response to the increased perceived cuckoo encounter rate, perhaps because higher potential parasitism threat did not transfer into greater actual parasitism rate. It remains to be assessed whether the lack of small-scale geographic variation in barn swallows' egg rejection rates persists because this species responds to selection by parasitism as a spatially contiguous evolutionary unit.

6.
Sensors (Basel) ; 20(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948060

RESUMO

The control effect of various intelligent terminals is affected by the data sensing precision. The filtering method has been the typical soft computing method used to promote the sensing level. Due to the difficult recognition of the practical system and the empirical parameter estimation in the traditional Kalman filter, a neuron-based Kalman filter was proposed in the paper. Firstly, the framework of the improved Kalman filter was designed, in which the neuro units were introduced. Secondly, the functions of the neuro units were excavated with the nonlinear autoregressive model. The neuro units optimized the filtering process to reduce the effect of the unpractical system model and hypothetical parameters. Thirdly, the adaptive filtering algorithm was proposed based on the new Kalman filter. Finally, the filter was verified with the simulation signals and practical measurements. The results proved that the filter was effective in noise elimination within the soft computing solution.

7.
Cardiovasc Pathol ; 45: 107190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31896440

RESUMO

Myocarditis continues to present challenges in diagnosis and management. The goal of this study is to determine the occurrence and manifestations of myocarditis in a heart failure (HF) population. The analyzed patients had acute or persistent HF and were referred over a 6-year period to a quaternary HF center for advanced HF therapies including mechanical circulatory support, left ventricular assist device (LVAD) implantation, and/or heart transplantation. The histopathological diagnosis of myocarditis was made based on the presence of an inflammatory infiltrate of the myocardium, typically with associated cardiomyocyte (CMC) damage, combined as indicated with immunohistochemical and molecular biology characterization. The pathological findings were correlated with a panel of clinical parameters and clinical course of the patients. Myocarditis was identified in 36 patients, with initial diagnoses made in 10 (40%) of 25 by endomyocardial biopsy (EMB), 1 by atrial biopsy (maze procedure), 7 (2.1%) of 331 at LVAD implantation, and 18 (7.8%) of 229 in the explanted heart. There were 20 cases of lymphocytic myocarditis, 4 cases of giant cell myocarditis, 3 cases of eosinophilic myocarditis, and 9 cases of lymphohistocytic with granulomas myocarditis - cardiac sarcoidosis. EMB was performed in 25 patients and was positive in 10 (40%) of cases. Myocarditis was found in 23 explanted hearts including 18 cases de novo and 5 cases with a previously positive specimen. Of the 23 explanted hearts, 21 were nonischemic cardiomyopathy and 2 were ischemic cardiomyopathy. Our findings show that, in patients presenting to a quaternary medical center, myocarditis can be manifest as acute HF as well as a complicating factor in chronic HF.

8.
Int J Biol Sci ; 16(2): 194-203, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929748

RESUMO

Ruxolitinib is a selective inhibitor of Jak1/2. Downstream signaling pathways of Jak, such as Stat3 and Akt/mTOR, are overactivated and contribute to renal interstitial fibrosis. Therefore, we explored the effect of Ruxolitinib on this pathological process. Unilateral ureteral obstruction (UUO) models and TGF-ß1-treated fibroblasts and renal tubular epithelial cells were adopted in this study. Ruxolitinib was administered to UUO mice and TGF-ß1-treated cells. Kidneys from UUO mice with Ruxolitinib treatment displayed less tubular injuries compared with those without Ruxolitinib treatment. Ruxolitinib treatment suppressed fibroblast activation and extracellular matrix (ECM) production in UUO kidneys and TGF-ß1-treated fibroblasts. Ruxolitinib treatment also blocked epithelial-mesenchymal transition (EMT) in UUO kidneys and TGF-ß 1-treated renal tubular epithelial cells. Moreover, Ruxolitinib treatment alleviated UUO-induced inflammation, oxidative stress and apoptosis. Mechanistically, Ruxolitinib treatment attenuated activation of both Stat3 and Akt/mTOR/Yap pathways. In conclusion, Ruxolitinib treatment can ameliorate UUO-induced renal interstitial fibrosis, suggesting that Ruxolitinib may be potentially used to treat fibrotic kidney disease.

9.
J Cell Commun Signal ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31925646

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors with poor prognosis. Aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor and emerging evidence shows it is associated with tumor initiation and promotion. However, the relationship between AHR and ESCC is not clear and it is meaningful to explore whether AHR could be a therapeutic target. In the present study, immunohistochemistry was performed to determine AHR expression levels in ESCC tissues. Knockdown of AHR expression in ESCC cell lines genetically and modulation of AHR by 3, 3'-diindolylmethane (DIM) pharmacologically both in vitro and in vivo were utilized to examine the corresponding alterations in cell growth, migration and invasion. Our study indicated that AHR expression levels were elevated in ESCC and associated with poor prognosis. Both knockdown and modulation of AHR inhibited tumor progression through down-regulating expression levels of PCNA, Bcl-2, Cyclin D1, MMP1, MMP2, MMP9 and up-regulating expression levels of Bax, Cleaved-Caspase 3. Our findings also indicated that repressing COX2/PGE2/STAT3 axis exerted inhibitory effects on ESCC both in vitro and in vivo assays. Taken together, AHR plays the key role in ESCC progression and targeting AHR as a therapeutic strategy with DIM is deserved for further exploration.

11.
Oncol Res ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907106

RESUMO

Cancer cell stemness is responsible for cancer relapse, distal metastasis, and drug resistance. Herewe identified that Frizzled 2 (Fzd2), one member of Wnt receptor Frizzled family, induced humanbreast cancer (BC) cell stemness via non-canonical Wnt pathways. Fzd2 was overexpressed inhuman BC tissues, and Fzd2 overexpression was associated with an unfavorable outcome. Fzd2knockdown (KD) disturbed the mesenchymal-like phenotype, migration and invasion of BC cells.Moreover, Fzd2 KD impaired BC cell mammosphere formation, reduced Lgr5+ BC cellsubpopulation, and enhanced sensitivity of BC cells to chemical agents. Mechanistically, Fzd2modulated and bound with Wnt5a/b and Wnt3 to activate several oncogenic pathways such as IL-6/Stat3, Yap1 and TGF-ß1/Smad3. These data indicate that Fzd2 contributes to BC cellmesenchymal-like stemness; targeting Fzd2 may inhibit BC recurrence, metastasis andchemoresistance.

12.
Sci Total Environ ; 704: 135342, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31896216

RESUMO

Volatile organic compounds (VOCs) concentrations of dry building materials can significantly affect the quality of indoor air. In this paper, a spatial fractional diffusion model is established by introducing fractional Fick's law, based on the fact that the pore structure of porous building materials has a strongly impact on VOCs diffusion. Furthermore, the areal porosity of the material is drawn into the convection mass transfer equation. The relevant parameters are estimated by a kind of optimization algorithm. The fractional nonlinear equations are tackled by the finite difference method combined with L2-algorithm. Results indicate that spatial fractional diffusion model agrees better with the experimental data than Deng and Kim's model. The spatial fractional diffusion model is used to describe the formaldehyde concentration in the particleboard according to the experimental data. Taking formaldehyde as a common substance, the influences of physical parameters on VOCs diffusion are predicted by this model. The results of numerical simulation demonstrate that the diffusion is consistent with the actual situation.

13.
Anal Bioanal Chem ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901960

RESUMO

A novel online two-dimensional supercritical fluid chromatography/reversed-phase liquid chromatography-triple-quadrupole mass spectrometry (2D SFC/RPLC-QQQ MS) method based on a vacuum solvent evaporation interface was developed for lipid profiling in human plasma, in which lipid classes were separated by the first-dimension SFC and different lipid molecular species were further separated by the second-dimension RPLC. All separation condition parameters were carefully optimized, and their influence on the chromatographic behavior of lipids is discussed. Finally, the recoveries of 11 lipid standards were all more than 88% for the interface. Besides, the limit of detection for these lipid standards was on the order of nanograms per milliliter, and the relative standard deviations of the peak area and retention time ranged from 1.54% to 19.85% and from 0.00% to 0.10%, respectively. The final 2D SFC/RPLC-QQQ MS method allowed the identification of 370 endogenous lipid species from ten lipid classes, including diacylglycerol, triacylglycerol, ceramide, glucosylceramide, galactosylceramide, lactosylceramide, sphingomyelin, acylcarnitine, phosphatidylcholine, and lysophosphatidylethanolamine, in human plasma within 38 min, which was used for screening potential lipid biomarkers in breast cancer. The 2D SFC/RPLC-QQQ MS method is a potentially useful tool for in-depth studies focused on complex lipid metabolism and biomarker discovery. Graphical Abstract.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31948076

RESUMO

Pollutant analysis and pollution source tracing are critical issues in air quality management, in which correlation analysis is important for pollutant relation modeling. A dynamic correlation analysis method was proposed to meet the real-time requirement in atmospheric management. Firstly, the spatio-temporal analysis framework was designed, in which the process of data monitoring, correlation calculation, and result presentation were defined. Secondly, the core correlation calculation method was improved with an adaptive data truncation and grey relational analysis. Thirdly, based on the general framework and correlation calculation, the whole algorithm was proposed for various analysis tasks in time and space, providing the data basis for ranking and decision on pollutant effects. Finally, experiments were conducted with the practical data monitored in an industrial park of Hebei Province, China. The different pollutants in multiple monitoring stations were analyzed crosswise. The dynamic features of the results were obtained to present the variational correlation degrees from the proposed and contrast methods. The results proved that the proposed dynamic correlation analysis could quickly acquire atmospheric pollution information. Moreover, it can help to deduce the influence relation of pollutants in multiple locations.

15.
Micron ; 131: 102818, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31968300

RESUMO

The extremely cold and arid conditions of Antarctica make it uniquely positioned to investigate fundamental questions regarding the persistence of life in extreme environments. Within the McMurdo Dry Valleys and surrounding mountain ranges are multiple ancient relict lakes, paleolakes, with lacustrine deposits spanning from thousands to millions of years in age. Here we present data from light microscopy, scanning electron microscopy, electron dispersive x-ray spectroscopy, and radiocarbon dating to catalog the remarkable range of life preserved within these deposits. This includes intact microbes and nanobacteria-sized cocci, CaCO3 precipitations consistent with biogenic calcium, previously undescribed net-like structures, possible dormant spores, and long-extinct yet exquisitely preserved non-vascular plants. These images provide an important reference for further microbiome investigations of Antarctic paleolake samples. In addition, these findings may provide a visual reference for the use of subsurface groundwater microbial communities as an analog for paleolake subsurface water on planets such as Mars.

16.
Chem Commun (Camb) ; 56(14): 2163-2166, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31970374

RESUMO

The co-existing mechanism of visible light mediated direct oxidation and C-H functionalization of amines was investigated by capturing all the intermediates using online mass spectrometry. The two-step dehydrogenation of amine involving a proton coupled electron transfer (PCET) process was revealed for the first time.

17.
Talanta ; 209: 120357, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31892081

RESUMO

Mass spectrometry imaging can effectively detect and reflect the information of molecular spatial distribution, and has been widely used for in situ analysis of endogenous or exogenous molecules in organisms. The present work applied the atmospheric pressure matrix-assisted laser desorption ionization mass spectrometry (AP-MALDI-MS) in the imaging of whole zebrafish slices exposed to fipronil. The chemical fingerprints in the range of m/z 600-950 showed significant differences in phospholipids between the fipronil exposed and untreated zebrafish groups. The major perturbed phospholipids were identified as PC(34:2), PC(34:1), PC(34:2)+Na, PC(36:4), PC(38:6), and PS(18:0/22:6), PI(18:0/20:4), PI(18:1/20:4) etc. Our results indicated that the exposure of fipronil obviously affected the phospholipid metabolism of zebrafish, especially of the fish eye region. Our work provides a new method or possibility for toxicological study and related metabolic analysis of pesticides in animals.

18.
Drug Deliv ; 27(1): 180-190, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31924103

RESUMO

In this work, a pH-sensitive liposome-polymer nanoparticle (NP) composed of lipid, hyaluronic acid (HA) and poly(ß-amino ester) (PBAE) was prepared using layer-by-layer (LbL) method for doxorubicin (DOX) targeted delivery and controlled release to enhance the cancer treatment efficacy. The NP with pH-sensitivity and targeting effect was successfully prepared by validation of charge reversal and increase of hydrodynamic diameter after each deposition of functional layer. We further showed the DOX-loaded NP had higher drug loading capacity, suitable particle size, spherical morphology, good uniformity, and high serum stability for drug delivery. We confirmed that the drug release profile was triggered by low pH with sustained release manner in vitro. Confocal microscopy research demonstrated that the NP was able to effectively target and deliver DOX into human non-small cell lung carcinoma (A549) cells in comparison to free DOX. Moreover, the blank NP showed negligible cytotoxicity, and the DOX-loaded NP could efficiently induce the apoptosis of A549 cells as well as free DOX. Notably, in vivo experiment results showed that the DOX-loaded NPs effectively inhibited the growth of tumor, enhanced the survival of tumor-bearing mice and improved the therapeutic efficacy with reduced side-effect comparing with free drug. Therefore, the NP could be a potential intelligent anticancer drug delivery carrier for cancer chemotherapy, and the LbL method might be a useful strategy to prepare multi-functional platform for drug delivery.

20.
Thorac Cancer ; 11(1): 55-61, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31766078

RESUMO

BACKGROUND: Previous investigations have revealed that miR-563 is associated with a number of diseases including the ossification of posterior longitudinal ligament, Parkinson's disease or drug resistance to leukemia. Yet, the role of miR-563 and its molecular mechanism in the initiation and progression of cancers has not been previously explored. In this study, we aimed to provide clues to the function of miR-563 and its direct target in lung cancer. METHODS: Online informatics software was applied to predict the target genes of miR-563. MiR-563 targeting LIN28B was evaluated through the luciferase reporter gene analysis. The effect of miR-563 on LIN28B at the level of RNA and protein was detected using RT-PCR and immunoblotting. The ability of proliferation of human lung cancer A549 was examined by MTT assay. RNA interference targeting LIN28B was examined through immunoblotting. The level of miR-563 and LIN28B and their correlation were analyzed in 27 cases of lung tumor tissues by real-time PCR. RESULTS: Oncogenic LIN28B was identified as one of the target genes of miR-563 in lung cancer cells. MiR-563 dose-dependently decreased the LIN28B RNA level and subsequently its protein level in the cells. Cell proliferation was suppressed by ectopic miR-563 expression and was accelerated after endogenous miR-563 was knocked down by its inhibitor. However, silence in LIN28B reversed promotion of cell proliferation by the inhibition of miR-563. In lung cancer tissues, miR-563 was decreased and negative correlation of miR-563 and LIN28B was shown. CONCLUSION: MiR-563 plays a tumor suppressive role in lung cancer progression via targeting oncogenic LIN28B.

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