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1.
J Exp Bot ; 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32453821

RESUMO

Although the salt overly sensitive (SOS) pathway plays essential roles in conferring salt tolerance in Arabidopsis thaliana, the regulatory mechanism underlying SOS gene expression remains largely unclear. In this study, AtPLATZ2 was found to function as a direct transcriptional suppressor of CBL4/SOS3 and CBL10/SCaBP8 in the Arabidopsis salt stress response. Compared with wild-type (WT) plants, transgenic plants constitutively overexpressing AtPLATZ2 exhibited increased sensitivity to salt stress. Loss of function of PLATZ2 had no observed salt-stress phenotype in Arabidopsis, while the double mutant of PLATZ2 and PLATZ7, led to weak salt stress tolerance than WT plans. Overexpression of AtPLATZ2 in transgenic plants decreased the expression of CBL4/SOS3 and CBL10/SCaBP8 both under normal and salt conditions. AtPLATZ2 directly bound to A/T-rich sequences in the CBL4/SOS3 and CBL10/SCaBP8 promoters in vitro and in vivo and inhibited CBL4/SOS3 promoter activity in the plant leaves. The salt sensitivity of #11 plants constitutively overexpressing AtPLATZ2 was restored by the overexpression of CBL4/SOS3 and CBL10/SCaBP8. Salt stress-induced Na+ accumulation in both the shoots and roots was more exaggerated in AtPLATZ2 overexpressing plants than WT. The salt stress-induced Na+ accumulation in #11 seedlings was also rescued by the overexpression of the CBL4/SOS3 and CBL10/SCaBP8. Furthermore, the transcription of AtPLATZ2 was induced in response to salt stress. Collectively, these results suggest that AtPLATZ2 suppresses plant salt tolerance by directly inhibiting of CBL4/SOS3 and CBL10/SCaBP8 and functions redundantly with PLATZ7.

2.
Phys Chem Chem Phys ; 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32458900

RESUMO

Electric-field-mediated magnetic properties were investigated in CoFe2O4/La0.67Sr0.33MnO3/Pb(Mg1/3Nb2/3)0.7Ti0.3O3 (CFO/LSMO/PMN-PT) heterostructures. The butterfly-like behavior of the magnetization under different electric fields indicates that the strain effect plays a critical role in the electric-field-mediated magnetic properties, leading to an increase in magnetization along the [100] direction but a decrease along the [01-1] direction in the CFO/LSMO/PMN-PT heterostructures. More interestingly, due to the large magnetostriction of the CFO layer, the coercivity of the CFO/LSMO/PMN-PT heterostructures decreases ∼50% along the [01-1] direction under the electric fields. The large modulation of the coercivity makes it possible to achieve electric-field-controlled magnetoresistance in the metal/CFO/LSMO/PMN-PT spin filter magnetic tunneling junctions.

4.
Reprod Biol Endocrinol ; 18(1): 41, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398019

RESUMO

BACKGROUND: Patients with severe oligospermia and nonobstructive azoospermia have very limited numbers of viable sperm in their epididymal and testicular samples. Thus, cryopreservation of their sperm is performed to avoid repeated sperm retrievals and to preserve their sperm from any side effects of any treatment regimens. MAIN BODY: The development of intracytoplasmic sperm injection technology has extended the therapeutic capacity of assisted reproductive technology for men with azoospermia via the surgical or percutaneous isolation of sperm from the testis/epididymis. The conventional cryopreservation techniques are inadequate for preserving individually selected sperm. The technique for freezing single sperm was first developed in 1997 and has been explored from the perspective of frozen carriers, freezing programs, and cryoprotectant formulations. Among these methods, advances in frozen carriers have directly improved single-sperm freezing technology. In this review, we evaluate the different technologies for the cryopreservation of single sperm by discussing the advantages and disadvantages of different freezing methods, their clinical applications, and the outcomes for a range of frozen carriers. CONCLUSION: Our review article describes the latest and current technologies implemented for the cryopreservation of single sperm that could potentially benefit patients with severe oligospermia and who rarely have any sperm in their ejaculate. This review provides a platform to understand the process and pitfalls of single-sperm cryopreservation to ensure further improvements in the cryopreservation technology in future studies.

5.
Sci Total Environ ; 720: 137408, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32325558

RESUMO

Solar-induced chlorophyll fluorescence (SIF) is a novel optical signal that has been successfully used to track plant dynamics with the influence of soil water deficit. However, the effect of atmospheric water deficit on SIF under the impact of soil water deficit still remains unclear. Here, continuous measurements of SIF (at 760 nm, F760) of winter wheat under different soil water deficit were collected with a self-developed system. Additionally, soil moisture and atmosphere parameters [including air temperature (Ta), relative air humidity (Rh), and photosynthetically active radiation at 400-700 nm (PAR)] were also synchronously collected by common commercial devices. Vapor pressure deficit (VPD) was calculated based on the measurements of Ta and Rh. The results showed that the driving effect of PAR on F760 was obvious as we expected. Additionally, such effects of PAR on AF760 (F760/PAR) and Fy760 (F760/L685, L685 was canopy radiance at 685 nm) still existed when the PAR influences were partially removed by the calculation of F760/PAR and F760/L685. Furthermore, the relationship of PAR with AF760 or Fy760 was observed to be strengthened under the situation of water deficit through the analysis of Pearson correlations. With the influence of PAR, the accelerative effect of VPD on SIF under soil water deficit was not always observed in our study. Nevertheless, when the effect of PAR was removed by using partial correlation, VPD showed much stronger correlation with SIF in soil water stressed plot than that in unstressed one both at diurnal and seasonal scales. These results revealed that soil water deficit might promote the effect of atmospheric water deficit on SIF. This study has great significance for the application of SIF in drought monitoring and health assessments in terrestrial ecosystem.

6.
PLoS One ; 15(3): e0230111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134976

RESUMO

Hypertension is the leading risk factor of cardiovascular disease and has profound effects on both the structure and function of the microvasculature. Abnormalities of the retinal vasculature may reflect the degree of microvascular damage due to hypertension, and these changes can be detected with fundus photographs. This study aimed to use deep learning technique that can detect subclinical features appearing below the threshold of a human observer to explore the effect of hypertension on morphological features of retinal microvasculature. We collected 2012 retinal photographs which included 1007 from patients with a diagnosis of hypertension and 1005 from normotensive control. By method of vessel segmentation, we removed interference information other than retinal vasculature and contained only morphological information about blood vessels. Using these segmented images, we trained a small convolutional neural networks (CNN) classification model and used a deep learning technique called Gradient-weighted Class Activation Mapping (Grad-CAM) to generate heat maps for the class "hypertension". Our model achieved an accuracy of 60.94%, a specificity of 51.54%, a precision of 59.27%, and a recall of 70.48%. The AUC was 0.6506. In the heat maps for the class "hypertension", red patchy areas were mainly distributed on or around arterial/venous bifurcations. This indicated that the model has identified these regions as being the most important for predicting hypertension. Our study suggested that the effect of hypertension on retinal microvascular morphology mainly occurred at branching of vessels. The change of the branching pattern of retinal vessels was probably the most significant in response to elevated blood pressure.

7.
Bioresour Technol ; 307: 123192, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32220819

RESUMO

This study investigated the interactions between volatile and char during biomass pyrolysis at 400 °C, employing a ß-5 lignin dimer and amino-modified graphitized carbon nanotube (CNT-NH2) as their models, respectively. The results demonstrated that both -NH2 and its carrier (CNT) facilitated the conversion of the ß-5 dimer, which significantly increased from 9.7% (blank run), to 61.6% (with CNT), and to 96.6% (with CNT-NH2). CNT mainly favored the breakage of C-O bond in the feedstock to produce dimers with a yield of 55.5%, while CNT-NH2 promoted the cleavage of both C-O and C-C bonds to yield monomers with a yield up to 63.4%. Such significant changes in the pyrolysis behaviors of the ß-5 lignin dimer after the introduction of CNT-NH2 were considered to be mainly caused by hydrogen-bond formations between -NH2 and the dimeric feedstock/products, in addition to the π-π stacking between CNT and aromatic rings.


Assuntos
Lignina , Nanotubos de Carbono , Biomassa , Carvão Vegetal , Temperatura Alta , Pirólise
8.
Ann Clin Transl Neurol ; 7(2): 210-218, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32031755

RESUMO

OBJECTIVE: To determine the efficacy and the prognostic value of amplitude-integrated electroencephalography (aEEG) in term and near-term neonates with high risk of neurological sequelae. METHODS: Infants of ≥35 weeks of gestation diagnosed with neonatal encephalopathy or with high risk of brain injury were included. All eligible infants underwent aEEG within 6 h after clinical assessment. The infants were followed up 12 months to evaluate neurological development. RESULTS: A total of 250 infants were eligible, of which 85 had normal aEEG, 81 had mildly abnormal aEEG, and 84 had severely abnormal aEEG. Of these infants, 168 were diagnosed with different neonatal encephalopathies, 27 with congenital or metabolic diseases, and 55 with high risk of brain injury. In all, 22 infants died, 19 were lost to follow-up, and 209 completed the follow-up at 12 months, of which 62 were diagnosed with a neurological disability. Statistical analysis showed that severely abnormal aEEG predicted adverse neurological outcome with a sensitivity of 70.2%, a specificity of 87.1%, a positive predictive value of 75.6%, and a negative predictive value of 83.7%. INTERPRETATION: aEEG can predict adverse outcomes in high-risk neonates and is a useful method for monitoring neonates with high risk of adverse neurological outcomes.

9.
Sci Total Environ ; 710: 136302, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31927285

RESUMO

Antimony (Sb) pollution was an emerging environmental risk in several contaminated waters, whereas its removal still presented as a severe challenge due to the lack of efficient adsorbent and its further removal mechanism. In this study, synthesized absorbents, Fe3O4 magnetic nanoparticles (Fe-MNPs) modified and dispersed with commonly used cationic surfactants, were applied to remove Sb contamination in real surface waters, its synthesized conditions, removal performance and mechanism were investigated by using batch experiments and characterization analyses. Optimum conditions on Sb(V) (the dominant form is Sb(OH)6-) removal by modified adsorbents were obtained as: cetylpyridinium chloride (CPC) coated on Fe-MNPs, mass ratio of Fe-MNPs: CPC = 4:1 and pH = 3-5. Magnetic properties of synthesized adsorbent were not affected, dispersibility was enhanced after fabrication of CPC, that indicated the Fe-MNPs@CPC could be separated and reused with external magnetic field. The adsorption efficiency of this low-cost adsorbent coated with CPC was superior than several traditional adsorbents. The practical application of Fe-MNPs@CPC in five types real waters from the Xikuangshan (XKS) Sb mine area and regeneration experiments by 1 M (mol/L) NaOH solution further confirm its practicability and reusability. Removal experiment results, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) spectra suggested that electrostatic attraction and surface bonding might responsible for the Sb(V) removal by Fe-MNPs modified with cationic surfactants.

10.
Environ Sci Pollut Res Int ; 27(10): 11000-11011, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31953759

RESUMO

The characteristics of subfractions of soil fulvic acid (FA3, FA5, FA7, FA9, and FA13) using stepwise elution from XAD-8 resin with pyrophosphate buffers were investigated by differential absorption spectroscopy (DAS) and differential fluorescence spectroscopy (DFS) combined with mathematical deconvolution and spectral indices. The log-transformed absorbance spectra (LTAS) exhibited three regions for both acidic-buffer-eluted subfractions (AESF) and neutral-buffer-eluted subfraction (NESF) and four regions for basic-buffer-eluted subfractions (BESF) according to the differences in spectral slopes. The DAS spectra of FA subfractions were closely fitted with seven Gaussian bands with maxima location at 199.66, 216.18 ± 1.50, 246.20 ± 3.85, 285.22 ± 7.26, 345.64 ± 5.30, 389.27, and 307.37 nm, respectively (R2 > 0.993). The content of salicylic-like and carboxyl groups in FA subfractions decreased, while the phenolic chromophore increased with elution sequence. From the 11 spectral indices, AESF had greater molecular weight, condensation, polymerization, hydroxyl radical production, humification degree, and terrigenous contribution, as well as contained more conjugated aromatic structures and less N-containing groups than NESF and BESF. The humification degree and humic characters of FA subfractions were closely associated to the aromaticity, molecular condensation, and DOM-metal-bound functional groups. The proper separation of FA into subfractions is beneficial for reducing its complexity and heterogeneity, which helps us to further explore its chemical properties and interactions with various contaminants in soil environments. Graphical abstract.

11.
J Cell Mol Med ; 24(2): 1233-1244, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31779055

RESUMO

Lung adenocarcinoma (LUAD), the most common non-small-cell lung cancer, is characterized by a dense lymphocytic infiltrate, which indicates that the immune system plays an active role in the development and growth of this cancer. However, no investigations to date have proposed robust models for predicting survival outcome for patients with LUAD in terms of tumour immunology. A total of 761 LUAD patients were included in this study, in which the database of The Cancer Genome Atlas (TCGA) was utilized for discovery, and the Gene Expression Omnibus (GEO) database was utilized for validation. Bioinformatics analysis and R language tools were utilized to construct an immune prognostic model and annotate biological functions. Lung adenocarcinoma showed a weakened immune phenotype compared with adjacent normal tissues. Immune-related gene sets were profiled, an immune prognostic model based on 2 immune genes (ANLN and F2) was developed with the TCGA database to distinguish cases as having a low or high risk of unfavourable prognosis, and the model was verified with the GEO database. The model was prognostically significant in stratified cohorts, including stage I-II, stage III-IV and epidermal growth factor receptor (EGFR) mutant subsets, and was considered to be an independent prognostic factor for LUAD. Furthermore, the low- and high-risk groups showed marked differences in tumour-infiltrating leucocytes, tumour mutation burden, aneuploidy and PD-L1 expression. In conclusion, an immune prognostic model was proposed for LUAD that is capable of independently identifying patients at high risk for poor survival, suggesting a relationship between local immune status and prognosis.

12.
Sci Total Environ ; 703: 134764, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31726300

RESUMO

Autochthonous dissolved organic matter (DOM) is increasingly released in lakes due to eutrophication, and thus affects the composition and environmental behaviors of DOM in eutrophic lakes. However, there are only limited studies on the molecular characteristics of autochthonous DOM and its influencing mechanisms. Herein, end-member DOM samples of macrophytes, algae, sediments and freshwater DOM samples in eutrophic lakes (Ch:Taihu and Dianchi) were collected and characterized by optical spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The results revealed the chemical structures of autochthonous DOM were more aliphatic and less oxidized, which was marked by increases in lipid compounds and decreases in the lignin components as compared to the allochthonous DOM-dominated freshwaters. More specially, algae-derived DOM contains more lipid compounds, while macrophyte-derived DOM was dominated by lignin and tannin compounds according to Van Krevelen plots. Sediment-derived DOM contained more N-containing compounds. The traditional optical indices indicated the relative aromaticity covaried with polyphenolic and polycyclic aromatics, whereas those reflecting autochthonous DOM covaried with more aliphatic compounds. Multivariate analysis of FT-ICR-MS data of end-members and freshwaters revealed the predominant terrestrial input to Lake Taihu and greater contribution of algae released DOM to Dianchi. This study provides critical information about the characteristics of autochthonous DOM at a molecular level and confirmed autochthonous DOM was compositionally distinct from allochthonous DOM. Overall autochthonous DOM should be gained more attention in the eutrophic lakes.

13.
Rapid Commun Mass Spectrom ; 34(9): e8715, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31886926

RESUMO

RATIONALE: Macleaya microcarpa (Maxim.) Fedde belongs to the genus Macleaya of the Papaveraceae family. Benzylisoquinoline alkaloids (BIAs) are considered the main bioactive constituents of M. microcarpa. METHODS: Using high-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (HPLC/QTOFMS/MS) we identified BIAs in the aerial parts of M. microcarpa in the early flowering stage. Target profiling and identification of BIAs in the extracted samples from the fresh aerial parts of M. microcarpa were exclusively based on a personal, accurate, mass database of known compounds and the mass spectral fragmentation behavior of Macleaya alkaloids. RESULTS: A total of 97 alkaloids, comprising 7 benzyltetrahydroisoquinolines, 1aporphine, 9 tetraprotoberberines, 3 protoberberines, 2 N-methyltetrahydroprotoberberines, 4 protopines, 47 dihydrobenzophenanthridines, and 24 benzophenanthridines, were identified from the fresh aerial parts of M. microcarpa, and 77 of these were detected for the first time in M. microcarpa. In addition, some of the screened alkaloids were related to the biosynthetic pathways of sanguinarine and chelerythrine. CONCLUSIONS: The integrated method is sensitive and reliable for screening and identifying trace or ultra-trace isoquinoline alkaloids and has contributed to a better understanding of BIAs in the fresh aerial parts of M. microcarpa.

14.
Mikrochim Acta ; 186(12): 806, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745660

RESUMO

A fluorescent "turn off-on" nanoprobe is described for highly sensitive and selective determination of the activity of the enzyme ß-glucosidase (ß-Glu). Firstly, cysteine modified CuInS2 quantum dots (Cys-CuInS2 QDs) were prepared from indium(III) and copper(II) salts and the presence of thiourea. The red fluorescence of the Cys-CuInS2 QDs, with excitation/emission maxima at 590/656 nm, is quenched by Cu(II). However, in the presence of ß-Glu and the cyanogenic glycoside, enzymatic hydrolysis leads to the formation of cyanide. The latter competitively binds to Cu(II) owing to its high affinity for cyanide. This restores the fluorescence of the Cys-CuInS2 QDs. Under the optimum conditions, fluorescence increases linearly in the 0.5-700 U·L-1 ß-Glu activity range. The detection limit is 0.2 U·L-1. The nanoprobe was applied to analyze spiked soil samples, and satisfactory results were obtained. The average recoveries of ß-Glu were in the range of 96-103%, and the RSD was lower than 4.0%. The fluorescent probe can also be used to screen for ß-Glu inhibitors as demonstrated for castanospermine as an example. Graphical abstractSchematic representation of the fluorescent nanoprobe for ß-glucosidase activity detection and inhibitor screening by taking advantage of the fluorescence (FL) "turn-off" and "turn-on" feature of cysteine capped CuInS2 quantum dots (Cys-CuInS2 QDs).

15.
Sci Rep ; 9(1): 16600, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719630

RESUMO

One of the health hazards of PM2.5 exposure is to induce pulmonary inflammatory responses. In our previous study, we demonstrated that exposing both the immortalized and primary human bronchial epithelial cells to PM2.5 results in a significant upregulation of VEGF production, a typical signaling event to trigger chronic airway inflammation. Further investigations showed that PM2.5 exposure strongly induces ATR/CHK1/p53 cascade activation, leading to the induction of DRAM1-dependent autophagy to mediate VEGF expression by activating Src/STAT3 pathway. In the current study, we further revealed that TIGAR was another transcriptional target of p53 to trigger autophagy and VEGF upregulation in Beas-2B cells after PM2.5 exposure. Furthermore, LKB1, but not ATR and CHK1, played a critical role in mediating p53/TIGAR/autophagy/VEGF pathway activation also by linking to Src/STAT3 signaling cascade. Therefore, on combination of the previous report, we have identified both ATR/CHK1/p53/DRAM1- and LKB1/p53/TIGAR- dependent autophagy in mediating VEGF production in the bronchial epithelial cells under PM2.5 exposure. Moreover, the in vivo study further confirmed VEGF induction in the airway potentially contributed to the inflammatory responses in the pulmonary vascular endothelium of PM2.5-treated rats. Therefore, blocking VEGF expression or autophagy induction might be the valuable strategies to alleviating PM2.5-induced respiratory injuries.

16.
Cancer Manag Res ; 11: 7813-7824, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695486

RESUMO

Background: Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors worldwide and the 5-year overall survival rate remains poor. Protein kinase, membrane associated tyrosine/threonine (PKMYT1) is overexpressed in several cancers and participate in tumor progression. However, the mechanism of PKMYT1 in ESCC is unclear. Purpose: The objective of our study was to demonstrate the the expression and role of PKMYT1 in ESCC. Patients and methods:   We detected the expression of PKMYT1 in ESCC patients and analysed the correlation with overall survival time and disease-free survival time. Then we detected PKMYT1 expression in ESCC cell lines and immortalized human esophageal epithelial cell line. Down-regulated PKMYT1 was carried out in KYSE70 and KYSE450 cells to invetigate the mechanism of PKMYT1 in ESCC cells. Results: PKMYT1 was up-regulated in tumor tissues and ESCC cell lines, and higher expression of PKMYT1 correlated with poorer overall survival in ESCC patients. Besides, in ESCC cell lines KYSE70 and KYSE450, knocking down PKMYT1 allowed more cells to skip G2/M checkpoint to complete mitosis, which promoted cell apoptosis, inhibited cell proliferation, and prevented the EMT phenotype in vitro. Meantime, we also observed that down-regulated PKMYT1 in ESCC cells suppressed AKT/mTOR signaling pathway. These results demonstrated PKMYT1 may act as an oncogene in ESCC. Conclusion: PKMYT1 plays an crutial role in ESCC progression, downregulated PKMYT1 might inhibit the development of ESCC by AKT/mTOR signaling pathway, and might be a novel target in the treatment of ESCC.

17.
Front Microbiol ; 10: 2035, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551972

RESUMO

Characterizing and engineering microbial communities for lignocellulosic biofuel production has received widespread attention. Previous research has established that Clostridium thermocellum JN4 and Thermoanaerobacterium thermosaccharolyticum GD17 coculture significantly improves overall cellulosic biofuel production efficiency. Here, we investigated this interaction and revealed the mechanism underlying the improved efficiency observed. In contrast to the previously reported mutualistic relationship, a harmful effect toward C. thermocellum JN4 was observed in these microbial consortia. Although T. thermosaccharolyticum GD17 relieves the carbon catabolite repression of C. thermocellum JN4 regarding obtaining more cellobiose or glucose released from lignocellulose, T. thermosaccharolyticum GD17 significantly hampers the growth of C. thermocellum JN4 in coculture. The increased formation of end products is due to the strong competitive metabolic advantage of T. thermosaccharolyticum GD17 over C. thermocellum JN4 in the conversion of glucose or cellobiose into final products. The possibility of controlling and rebalancing these microbial consortia to modulate cellulose degradation was achieved by adding T. thermosaccharolyticum GD17 stimulants into the system. As cellulolytic bacteria are usually at a metabolic disadvantage, these discoveries may apply to a large proportion of cellulosic biofuel-producing microbial consortia. These findings provide a reference for engineering efficient and modular microbial consortia for modulating cellulosic conversion.

18.
Front Immunol ; 10: 1843, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474976

RESUMO

Influenza A virus (IAV) remains a major public health threat in the world, as indicated by the severe pneumonia caused by its infection annually. Interleukin-6 (IL-6) involved excessive inflammatory response to IAV infection profoundly contributes to the virus pathogenesis. However, the precise mechanisms underlying such a response are poorly understood. Here we found from both in vivo and in vitro studies that IAV not only induced a surge of IL-6 release, but also greatly upregulated expression of suppressor of cytokine signaling-3 (SOCS3), the potent suppressor of IL-6-associated signal transducer and activator of transcription 3 (STAT3) signaling. Interestingly, there existed a cytokine-independent mechanism of the robust induction of SOCS3 by IAV at early stages of the infection. Furthermore, we employed SOCS3-knockdown transgenic mice (TG), and surprisingly observed from virus challenge experiments using these mice that disruption of SOCS3 expression provided significant protection against IAV infection, as evidenced by attenuated acute lung injury, a higher survival rate of infected animals and lower viral load in infected tissues as compared with those of wild-type littermates under the same condition. The activity of nuclear factor-kappa B (NFκB) and the expression of its target gene IL-6 were suppressed in SOCS3-knockdown A549 cells and the TG mice after infection with IAV. Moreover, we defined that enhanced STAT3 activity caused by SOCS3 silencing was important for the regulation of NFκB and IL-6. These findings establish a critical role for IL-6-STAT3-SOCS3 axis in the pathogenesis of IAV and suggest that influenza virus may have evolved a strategy to circumvent IL-6/STAT3-mediated immune response through upregulating SOCS3.

19.
Sci Total Environ ; 692: 818-832, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539988

RESUMO

The past ecosystem responses to climate variability makes it possible to view the sensitivity of ecosystems to climate-forced state shifts. To test the hypothesis that the development of peatland in the Changbai Mountains responds to the variability of the East Asian summer monsoon (EASM), the developmental history of the Hani peatland was investigated based on peat basal ages. It can be concluded that the development of Hani peatland is the paludification. The development of the northern region started 13,685 cal. yr BP, while that of the southern region was initiated 7705 cal. yr BP. In addition, the moisture changes and development of the Hani peatland can be divided into three periods. From 16 to 7 ka cal. BP, the increase in the EASM was induced by the lower sea level and southward displacement of the Western Pacific Subtropical High (WPSH), resulting in increasing moisture in the Hani peatland. Peat was gradually established in the northern region. From 7 to 2 ka cal. BP, the increased relative sea level and northward displacement of the WPSH induced the maximum EASM. The EASM and Northeast Monsoon (NEM) induced the maximum moisture in the Hani peatland. Both the northern and southern regions were covered with peat during this period. Since 2 ka cal. BP, the decreasing EASM might be related to the seasonal decrease in the Northern Hemisphere summer insolation and ENSO intensity. Thus, the decreasing EASM induced the decrease in the moisture in the Hani peatland. Peat further accumulated in both the northern and southern regions. This study will help to understand the future EASM behavior in NE China and the development of similar peatlands in response to ongoing and future climatic change.


Assuntos
Solo/química , Áreas Alagadas , China , Mudança Climática , Estações do Ano
20.
J Immunother Cancer ; 7(1): 215, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395078

RESUMO

BACKGROUND: Colorectal cancer (CRC) is one of the most common forms of cancer worldwide. The tumor microenvironment plays a key role in promoting the occurrence of chemoresistance in solid cancers. Effective targets to overcome resistance are necessary to improve the survival and prognosis of CRC patients. This study aimed to evaluate the molecular mechanisms of the tumor microenvironment that might be involved in chemoresistance in patients with CRC. METHODS: We evaluated the effects of CCL20 on chemoresistance of CRC by recruitment of regulatory T cells (Tregs) in vitro and in vivo. RESULTS: We found that the level of CCL20 derived from tumor cells was significantly higher in Folfox-resistant patients than in Folfox-sensitive patients. The high level of CCL20 was closely associated with chemoresistance and poor survival in CRC patients. Among the drugs in Folfox chemotherapy, we confirmed that 5-FU increased the expression of CCL20 in CRC. Moreover, CCL20 derived from 5-FU-resistant CRC cells promoted recruitment of Tregs. Tregs further enhanced the chemoresistance of CRC cells to 5-FU. FOXO1/CEBPB/NF-κB signaling was activated in CRC cells after 5-FU treatment and was required for CCL20 upregulation mediated by 5-FU. Furthermore, CCL20 blockade suppressed tumor progression and restored 5-FU sensitivity in CRC. Lastly, the expression of these signaling molecules mediating chemoresistance was closely correlated with poor survival of CRC patients. CONCLUSIONS: CRC cell-secreted CCL20 can recruit Tregs to promote chemoresistance via FOXO1/CEBPB/NF-κB signaling, indicating that the FOXO1/CEBPB/NF-κB/CCL20 axis might provide a promising target for CRC treatment.

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