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3.
Sci Total Environ ; 698: 134316, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783464

RESUMO

Dark carbon fixation (DCF) by chemolithotrophic microbes can make considerable contribution to inorganic carbon fixation in aquatic ecosystems. However, little is known about the importance and diversity of chemolithotrophic microbes in cascade reservoir sediments. In this study, we determined the potential DCF rates of sediments of three cascade reservoirs in Wujiang River basin by carbon isotopic labeling. The results showed that the DCF rates of the surface sediments ranged from 1.5 to 14.7 mmol C m-2 d-1. The ratio of DCF to mineralization rate of sediment organic matter of surface sediment was between 11.6%~60.9%. High-throughput sequencing analysis of cbbL and cbbM genes involved in Calvin Benson Cycle indicated that cbbL-carrying CO2-assimilating bacteria included diverse functional groups, while cbbM type was mostly involved in sulfur oxidation. The sediments of Hongfeng (HF) reservoir, which has much longer hydraulic residence time (HRT) and locates in most upstream of a major tributary of Wujiang River, have substantially higher DCF rates. The cbbL and cbbM communities in HF were dominated by sulfur oxidizing bacteria, and were largely different from that in the other two reservoirs. Our results suggested that chemolithotrophy plays an important role in carbon cycling of sediments in cascade reservoir. Meanwhile, HRT and relative location of cascade reservoirs are the key control factors of both DCF and composition of autotrophic microbial communities in cascade reservoir sediments.

4.
Cancer Lett ; 468: 14-26, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31600529

RESUMO

Deregulation of SOX9 in esophageal cancer has been reported. However, the regulatory mechanisms underlying SOX9 during esophageal squamous cell carcinoma (ESCC) progression remain poorly understood. Here, we independently confirmed the increased SOX9 expression in two ESCC cohorts and its correlation with poor prognosis. We demonstrated that SOX9 was required for maintaining self-renewal, motility, and chemoresistance in vitro and that ectopic expression of SOX9 promoted tumorigenicity in vivo. Screening for potential SOX9-regulated miRNAs revealed that target genes of differentially expressed miRNAs were enriched in the PI3K/AKT signaling pathway and identified the downregulated miR-203a as a candidate. Mechanistically, SOX9 activation caused repression of miR-203a transcription by binding to miR-203a promoter, thus preventing the miR-203a-mediated inhibition of multiple PI3K/AKT/mTOR components, including PIK3CA, AKT2, and RPS6KB1. The association between SOX9 expression and PI3K/AKT/mTOR signaling was further validated in clinical samples. Moreover, rapamycin treatment attenuated the SOX9-mediated malignant phenotypes and potentiated cisplatin-mediated inhibition of tumor growth. Together, these findings uncover a novel activation of the PI3K/AKT pathway by the SOX9/miR-203a axis and define a subgroup of patients who may benefit from targeted therapy.

5.
Sci Total Environ ; 698: 134304, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514024

RESUMO

To mitigate the grassland degradation in the Mongolian Plateau (MP), both China and Mongolia governments have carried out a series of new policies and ecological projects. However, the effect of such restoration measures on the productivity of grassland in the MP under different political systems remains unclear. Here we study the effects of land use and land cover change, human activities and climate change on the net primary productivity (NPP) of grassland in Mongolia (MG) and Inner Mongolia (IM) from 2001 to 2014. Results showed that the area of grassland increased in both MG and IM, accounted for 4.45 × 104 and 10.31 × 104 km2, respectively. The extended grassland contributed 4.34 × 108 Gg C (Gg = 109 g) to the total NPP, while the loss of grassland led to a decrease of 0.19 × 108 Gg C. The total NPP of grasslands in 2014 increased about 17.88% and 30.49% respectively in MG and IM since 2001. Specifically, IM exhibited a higher increase in land converted NPP than MG. The area of grassland restoration in IM and MG accounted for 90.21% and 81.45%, respectively, indicating that the grassland of the MP was restored. Although human activity was the dominant factor on grassland degradation, which was accounted for 9.79% and 18.55% in IM and MG, it has a positive effect on most of the grassland NPP in the MP. Overall, policy measures and ecological projects in IM brought a more positive effect compared with that in MG.

6.
J Cell Physiol ; 235(2): 1339-1348, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31256441

RESUMO

This study aimed to investigate the molecular mechanisms underlying the roles of metformin (MET) and Sorafenib (SOR) in the treatment of endometrial hyperplasia (EH) in polycystic ovary syndrome (PCOS). Effects of MET and SOR on the area of endometrium and myometrium were detected. Western blot analysis and immunohistochemistry assays were carried out to detect the levels of mammalian target of rapamycin complex 1 (mTORC1), mTORC2, LC3-II, P62, and Caspase-3 in rats and cultured cells. Furthermore, cell counting kit-8 assay and flow cytometry analysis was carried out to determine the apoptotic profiles of treated cells. MET and SOR could apparently decrease the areas of endometrium and myometrium in PCOS. MET notably enhanced the expression of LC3-II and Caspase-3 in PCOS while substantially reducing the level of mTORC1 and P62. Similarly, SOR also enhanced the expression of LC3-II and Caspase-3 in PCOS while substantially reducing the level of mTORC2 and P62. Treatment with MET and SOR significantly inhibited the proliferation of HCC-94 and HEC-1-A cells while promoting their apoptosis by upregulating the expression of Caspase-3. In cells treated with MET, the expression of mTORC1 and LC3-II was upregulated while the expression of P62 was downregulated. Similarly, in cells treated with SOR, the expression of mTORC2 and LC3-II was also upregulated while the expression of P62 was also downregulated. Furthermore, MET showed no effect on mTORC2 expression, while SOR showed no effect on mTORC1 expression. In this study, we suggested that MET and SOR alleviated the risk of EH in PCOS via the mTORC1/autophagy/apoptosis axis and mTORC2/autophagy/apoptosis axis, respectively.

7.
J Nanosci Nanotechnol ; 20(4): 2308-2315, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492241

RESUMO

While most of the fluorescent nanoparticles used in stimulated emission depletion (STED) microscopy have a long excitation wavelength, many applications need shorter wavelength fluorophores, which are yet to be developed for STED microscopy applications. Here, three kinds of fluorescent nanoparticles, namely silica nanoparticles (NFv465), fluoro-max blue aqueous fluorescent nanoparticles (FBs) and light yellow nanoparticles (LYs) with short excitation wavelength in violet band have been studied to assess whether they are applicable in STED microscopy. The experimental configuration utilizes a 405 nm continuous wave (CW) laser as excitation beam and a 532 nm CW laser as depletion beam. We compare the photostability, photobleaching and depletion efficiency of three kinds of fluorescent nanoparticles in a series of experiments. Light yellow nanoparticles are proved to be a good candidate as fluorophore in STED microscopy.

8.
J Nanosci Nanotechnol ; 20(4): 2416-2422, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492256

RESUMO

In this paper, loofah sponge-based activated carbon (LAC) is prepared via loofah sponge as precursors and KOH as activator. N2 adsorption, X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the surface morphology and the structure of loofah sponge-based activated carbon. Cyclic voltammetry (CV), galvanostatic charge/discharge cycle and electrochemical impedance spectroscopy (EIS) were utilized to test electrochemical properties of loofah spongebased activated carbon. The results showed that loofah sponge-based activated carbon (LAC-700) prepared at 700 °C has the highest specific surface area (936 m²·g-1). The material delivers specific capacitance of 152.89 F·g-1 at the current density of 0.1 A·g-1, and specific capacitance of 116.69 F·g-1 at the current density of 5 A·g-1 in 30 wt% KOH aqueous electrolyte.

9.
Int J Biol Macromol ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794826

RESUMO

Agouti signaling protein (ASP) is a secreted paracrine protein that has been widely reported to function in melanogenesis and obesity and could potentially be a core protein that regulates the color and fatty phenotype of P. sinensis. In this study, we screened out interacting proteins of ASP by combined co-immunoprecipitation mass spectrometry (CoIP-MS), yeast two hybrid (Y2H) analysis, and computational predictions. We performed docking of ASP with its well-known receptor melanocortin receptor 4 (MC4R) to predict the binding capacity and to screen out actual ASP interacting proteins, CoIP-MS was performed where identified 32 proteins that could bind with ASP and Y2H confirmed seven proteins binding with ASP directly. CoIP-MS and Y2H screening results including PPI prediction revealed that vitronectin (VTN), apolipoprotein A1 (APOA1), apolipoprotein B (APOB), and filamin B (FLNB) were the key interacting proteins of ASP. VTN, APOA1, and APOB are functional proteins in lipid metabolism and various skin disorders, suggesting ASP may function in lipid metabolism through these partners. This study provided protein-protein interaction information of ASP, and the results will promote further research into the diverse roles of ASP, as well as its binding partners, and their function in different strains of P. sinensis.

10.
J Chromatogr A ; : 460723, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31796249

RESUMO

Quantitative determination of endogenous compounds in biological samples has still been challenged by the absence of authentic blank matrix. Alternative strategy of surrogate matrix for preparing reference samples are prevalent due to its low cost and high availability. However, the evaluation system of surrogate matrix is not perfect. Herein, a novel multifunctional isotopic standards based steroidomics strategy was developed. Isotope-labeled standards were used not only as internal standards but also for the evaluation the feasibility of surrogate matrix, which improved the accuracy of assessment and could provide a new prospect for the quantitative analysis of endogenous compounds. Based on this approach, a detailed optimization from LC separation, MS detection to extraction conditions for global steroids in the steroidogenesis was firstly carried out. Characteristics and regularities of steroids in LC-MS were summarized to make references for further targeted or untargeted steroidomics study. Then eighteen steroids were quantified with high accuracy and high sensitivity in plasma from four types of cancer patients and healthy subjects using 1% BSA in PBS as surrogate matrix. And multi-steroids indexes with the best discriminating ability for lung, colorectal, breast and gastric cancer in different genders were identified successfully with Student's t-test, PLS-DA and logistic regression- ROC curve analysis. Finally, efficient cancer screening workflow was established by integrating the amine submetabolomics and lipidomics data of our previous studies. Taken together, the integrated steroidomics strategy could shed a light on the guidance for further steroidome as well as other endogenous compounds analysis and may provide a powerful tool for cancer diagnosis.

11.
Mol Ther Nucleic Acids ; 18: 1039-1048, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31785579

RESUMO

Alternative splicing (AS), an important post-transcriptional regulatory mechanism that regulates the translation of mRNA isoforms and generates protein diversity, has been widely demonstrated to be associated with oncogenic processes. In this study, we systematically analyzed genome-wide AS patterns to explore the prognostic implications of AS in endometrial cancer (EC). A total of 2,324 AS events were identified as being associated with the overall survival of EC patients, and eleven of these events were further selected using a random forest algorithm. With the implementation of a generalized, boosted regression model, a prognostic AS model that aggregated these eleven markers was ultimately established with high performance for risk stratification in EC patients. Functional analysis of these eleven AS markers revealed various potential signaling pathways implicated in the progression of EC. Splicing network analysis demonstrated the notable correlation between the expression of splicing factors and AS markers in EC and further determined eight candidate splicing factors that could be therapeutic targets for EC. Taken together, the results of this study present the utility of AS profiling in identifying biomarkers for the prognosis of EC and provide comprehensive insight into the molecular mechanisms involved in EC processes.

12.
Nucleic Acids Res ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799604

RESUMO

Genome editing typically involves recombination between donor nucleic acids and acceptor genomic sequences subjected to double-stranded DNA breaks (DSBs) made by programmable nucleases (e.g. CRISPR-Cas9). Yet, nucleases yield off-target mutations and, most pervasively, unpredictable target allele disruptions. Remarkably, to date, the untoward phenotypic consequences of disrupting allelic and non-allelic (e.g. pseudogene) sequences have received scant scrutiny and, crucially, remain to be addressed. Here, we demonstrate that gene-edited cells can lose fitness as a result of DSBs at allelic and non-allelic target sites and report that simultaneous single-stranded DNA break formation at donor and acceptor DNA by CRISPR-Cas9 nickases (in trans paired nicking) mostly overcomes such disruptive genotype-phenotype associations. Moreover, in trans paired nicking gene editing can efficiently and precisely add large DNA segments into essential and multiple-copy genomic sites. As shown herein by genotyping assays and high-throughput genome-wide sequencing of DNA translocations, this is achieved while circumventing most allelic and non-allelic mutations and chromosomal rearrangements characteristic of nuclease-dependent procedures. Our work demonstrates that in trans paired nicking retains target protein dosages in gene-edited cell populations and expands gene editing to chromosomal tracts previously not possible to modify seamlessly due to their recurrence in the genome or essentiality for cell function.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31786739

RESUMO

PROPOSE: Poly (ADP-ribose) polymerase 1 inhibitors were originally investigated as anti-cancer therapeutics with BRCA1/2 genes mutation. Here, we investigate the effectiveness of a novel PARP1 inhibitor fluzoparib, for enhancing the radiation sensitivity of NSCLC cells lacking BRCA1/2 mutation. METHODS: We used MTS assays, western blotting, colony formation assays, immunofluorescence staining, and flow cytometry to evaluate the radiosensitization of NSCLC cells to fluzoparib and explore the underlying mechanisms in vitro. Through BRCA1 and RAD50 genes knockdown, we established dysfunctional homologous recombination (HR) DNA repair pathway models in NSCLC cells. We next investigated the radiosensitization effect of fluzoparib in vivo using human NSCLC xenograft models in mice. The expression of PARP1 and BRCA1 in human NSCLC tumor samples was measured by immunohistochemistry. Furthermore, we sequenced HR-related gene mutations and analyzed their frequencies in advanced NSCLC. RESULTS: In vitro experiments in NSCLC cell lines along with in vivo experiments using an NSCLC xenograft mouse model demonstrated the radiosensitization effect of fluzoparib. The underlying mechanisms involved increased apoptosis, cell-cycle arrest, enhanced irradiation-induced DNA damage, and delayed DNA-damage repair. Immunohistochemical staining showed no correlation between the expression of PARP1 and BRCA1. Moreover, our sequencing results revealed high mutation frequencies for the BRCA1/2, CHEK2, ATR, and RAD50 genes. CONCLUSION: The potential therapeutic value of fluzoparib for increasing the radiation sensitivity of NSCLC is well confirmed. Moreover, our findings of high mutation frequencies among HR genes suggest that PARP1 inhibition may be an effective treatment strategy for advanced non-small cell lung cancer patients.

14.
J Environ Sci (China) ; 86: 154-163, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787180

RESUMO

Previous studies have reported associations of short-term exposure to different sources of ambient fine particulate matter (PM2.5) and increased mortality or hospitalizations for respiratory diseases. Few studies, however, have focused on the short-term effects of source-specific PM2.5 on emergency room visits (ERVs) of respiratory diseases. Source apportionment for PM2.5 was performed with Positive Matrix Factorization (PMF) and generalized additive model was applied to estimate associations between source-specific PM2.5 and respiratory disease ERVs. The association of PM2.5 and total respiratory ERVs was found on lag4 (RR = 1.011, 95%CI: 1.002, 1.020) per interquartile range (76 µg/m3) increase. We found PM2.5 to be significantly associated with asthma, bronchitis and chronic obstructive pulmonary disease (COPD) ERVs, with the strongest effects on lag5 (RR = 1.072, 95%CI: 1.024, 1.119), lag4 (RR = 1.104, 95%CI: 1.032, 1.176) and lag3 (RR = 1.091, 95%CI: 1.047, 1.135), respectively. The estimated effects of PM2.5 changed little after adjusting for different air pollutants. Six primary PM2.5 sources were identified using PMF analysis, including dust/soil (6.7%), industry emission (4.5%), secondary aerosols (30.3%), metal processing (3.2%), coal combustion (37.5%) and traffic-related source (17.8%). Some of the sources were identified to have effects on ERVs of total respiratory diseases (dust/soil, secondary aerosols, metal processing, coal combustion and traffic-related source), bronchitis ERVs (dust/soil) and COPD ERVs (traffic-related source, industry emission and secondary aerosols). Different sources of PM2.5 contribute to increased risk of respiratory ERVs to different extents, which may provide potential implications for the decision making of air quality related policies, rational emission control and public health welfare.

15.
Chemistry ; 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31788882

RESUMO

Ultralong organic phosphorescence (UOP) of metal-free organic materials has received considerable attention owing to their long-lived emission lifetimes recently, which are attractive alternatives to persistent luminescence in inorganic phosphors. The enormous research efforts have been devoted on improving UOP performance in metal-free organic phosphors by promoting intersystem crossing (ISC) process and suppressing the non-radiative decay of triplet state excitons. This minireview summarizes recent advance of the rational approaches in manipulating UOP properties of small molecular crystals, such as phosphorescence lifetime, efficiency and emission colors. Finally, the present challenges and future development of this field are prospected at last. This review will outline a guideline to rationally design more advanced metal-free organic phosphorescence materials for potential applicaitons.

16.
Sci Eng Ethics ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755006

RESUMO

In order to solve a series of problems brought about by rapid development of science and technology, it is necessary not only to conduct in-depth research on science and technology ethics, but also to strengthen ethics education in science and technology. China's five technical universities (5TU) exemplify the specific situation and characteristics of ethics at Chinese technical universities, and can be compared to the situation in South Africa. China's ethics education in the 5TU emphasizes the use of traditional ideological and cultural resources, and practical cases. The teaching methods focus on combining traditional Chinese ethics with foreign experience and teaching methods, aiming at cultivating students' ability to solve specific problems in the real world. This paper also evaluates and reflects on the short-term and long-term effects of China's ethics education in science and technology, revealing some special problems. Ethics education in science and technology at the 5TU is based on the principle of "unity of knowledge and behaviour". It is hoped that China's ethics education founded on traditional Chinese thought, can make a valuable contribution to the development of global engineering ethics.

17.
J Fish Biol ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755106

RESUMO

A continuous cell line MPF derived from the fin of black carp Mylopharyngodon piceus was established and characterized in this study. Mylopharyngodon piceus fin (MPF) cells were subcultured for more than 80 passages with high viability recovery after long-term storage. The karyotyping analysis revealed that MPF had a modal diploid chromosome number (2n = 48) and identical ribosomal RNA sequence with black carp. In addition, the expression of pluripotency-associated markers including nanog, oct4 and vasa, were detected in MPF. The transient transfection efficiency of MPF reached 23% with a fluorescent reporter by modified electroporation and stable expression of red fluorescent MPF was established by the baculovirus system, indicating that MPF is an ideal platform for studying gene functions in vitro. Lastly, cytopathic effects were also observed and RNA transcripts of a viral gene increased after infection by spring viremia of carp virus (SVCV), suggesting that MPF could be an alternative tool for investigating pathogen-host interactions in black carp. In conclusion, a fin cell line that is susceptible to SVCV was established as a potential adult stem-cell line, providing a suitable tool for future genetic analyses and pathogen-host studies in black carp. This article is protected by copyright. All rights reserved.

18.
Mol Ther Nucleic Acids ; 18: 1009-1022, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31778954

RESUMO

Recently, emerging evidence shows that dysregulation of circadian genes is closely associated with liver fibrosis. However, how dysregulation of circadian genes promotes liver fibrosis is unknown. In this study, we show that neuronal PAS domain protein 2 (NPAS2), one of the core circadian molecules that has been shown to promote hepatocarcinoma cell proliferation, significantly contributed to liver fibrogenesis. NPAS2 is upregulated in hepatic stellate cells (HSCs) after fibrogenic injury, which subsequently contributes to the activation of HSCs. Mechanistically, NPAS2 plays a profibrotic role via direct transcriptional activation of hairy and enhancer of split 1 (Hes1), a critical transcriptor of Notch signaling for the fibrogenesis process, in HSCs. Our findings demonstrate that NPAS2 plays a critical role in liver fibrosis through direct transcriptional activation of Hes1, indicating that NPAS2 may serve as an important therapeutic target to reverse the progression of liver fibrosis.

19.
Opt Express ; 27(20): 27726-27736, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684535

RESUMO

The Au@SiO2 nanorods with two plasmonic resonance bands are used to enhance and tune the emission of binary lanthanide (Eu/Tb) complexes. The emissions of Tb and Eu ions are both enhanced, the maximum enhancement is over 100-fold. Meanwhile the ratio and relative intensity of the red/green bands is altered by the strong coupling between complexes and nanorods, tuning the color of emission from green to yellow under excitation of 292 nm and improving the color purity from orange to red under excitation of 360 nm. The underlying physics of the lanthanide complex-plasmonic nanorod composite system is analyzed, which deepen the understanding of the interaction between complexes and plasmon nanoparticles.

20.
Endocr J ; 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31685721

RESUMO

Ectopic parathyroid adenomas (PAs) can occur in numerous locations and are thought to be the cause of a significant portion of failed primary surgery for hyperparathyroidism. PA is a rare cause of hoarseness, which may be harbingers of a malignant process. Here, we describe an unusual case of an ectopic PA in the carotid sheath presenting as unilateral vocal cord paralysis (VCP). A 49-year-old lady presented with a 1-week history of hoarseness, irritating cough and shortness of breath. Fibreoptic laryngoscopy revealed left VCP. Ultrasound and computed tomography of the neck demonstrated a mass in the carotid sheath. Laboratory investigations revealed hypercalcemia (3.10 mmol/L), hypophosphatemia (0.81 mmol/L) and elevated intact parathyroid hormone (iPTH) level (381.6 pg/mL), despite of a negative 99mTc-sestamibi scan. After more rigorous tests, the ectopic tumor adjacent to the left vagus nerve was successfully resected, with subsequent histopathological confirmation of PA. The patient eventually got a normal iPTH level and serum calcium postoperatively, and regular voice function was also regained 4 months after surgery. This case emphasizes the importance of broad differential diagnosis and thorough workup. Although most patients with PA present with hypercalcemia, this disease entity also need to be considered in the differentials of neck masses and VCP.

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