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1.
Talanta ; 206: 120199, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514856

RESUMO

A new class of intracellular signal amplification approach, integrating biodegradable manganese dioxide (MnO2) nanosheet with target-triggered DNAzyme recycling amplification in one nanosystem, was developed for highly specific and sensitive monitoring of microRNAs (miRNAs) in living cells. Briefly, the MnO2 nanosheets were employed as carrier and quencher for the hairpin-locked-DNAzyme strands (H1). Upon entering cells, the surface-adsorbed strands (H1) can be released due to the degradation of the MnO2 nanosheets by cellular glutathione. Subsequently, the hybridization reaction between target miRNAs and H1 probe induced the conformation alteration of the hairpin probes H1, formed an "active" DNAzyme. With the assistor of Mg2+, the DNAzyme was activated and induced the release of the fluorophores labeled DNA fragment, which achieved the restoration of fluorescence signal. Meanwhile, the target molecules was released and hybridized with the other H1 strand to initiate another cycle of activation, cleavage, and turnovers, which producing enhanced fluorescence signal for sensitive analysis of intracellular miRNAs. Furthermore, fluorescence imaging experiments demonstrated that the MnO2-DNAzyme nanosystem could visually detect microRNA-21 in cancer cells. The proposed strategy provides a good platform for highly sensitive detection and imaging analysis of various intracellular miRNAs in situ.

2.
J Hazard Mater ; 382: 121120, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31487667

RESUMO

Low-cost and high-performance materials or techniques that could synergistically remove inorganic heavy metals and organic pollutants in a simple manner are highly desired. Herein, we report a simple and facile strategy by converting poisonous heavy metals into photocatalyst for the in-situ photodegradation of organic pollutants employing steel slag-derived calcium silicate hydrate (CSH). The CSH was synthesized by alkali activation method and showed hierarchical structure and amorphous phase. And, the material exhibited excellent adsorption performance towards all selected heavy metals. After adsorption, the heavy metals were converted into the corresponding amorphous metal hydroxides on the surface of CSH. The resulting CSH-supported amorphous metal hydroxides can act as visible-light photocatalysts for the photodegradation of organic pollutants. The optimal results for the whole water purification route using CSH are > 100 mg/g adsorption capacity for Cu2+ and ˜63% / 8 h photodegradation efficiency for methylene blue under visible light. The total cost for the whole route is < 0.1 $/g pollutants, much lower than traditional technologies. The strategy using steel slag derived-CSH not only meets the requirements for high-performance and low-cost materials, but also resolves the challenging issues of developing an all-in-one treatment for heavy metal ions and organic pollutants, which will be of great significance to wastewater purification.

3.
Acta Neurochir Suppl ; 127: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407066

RESUMO

BACKGROUND: Subarachnoid hemorrhage (SAH) is a severe and emergent cerebrovascular disease, the prognosis of which usually very poor. Microthrombi formation highlighted with inflammation occurs early after SAH. As the main cause of DCI, microthrombosis associated with the prognosis of SAH. The aim of this study was to show HSP90 inhibitor 17-AAG effect on microthrombosis after SAH in rats. METHODS: Ninety-five SD rats were used for the experiment. For time course study, the rats were randomly divided into five groups: sham group and SAH group with different time point (1d, 2d, 3d, 5d). Endovascular perforation method was conducted for SAH model. Neurological score, SAH grade, and mortality were measured after SAH. The samples of the left hemisphere brain were collected. The expression of HSP90 was detected by Western blot. The microthrombosis after SAH in rats' brain was detected by immunohistochemistry. For mechanism study, rats were randomly divided into three groups: sham, SAH + vehicle, and SAH +17-AAG (n = 6/group). 17-AAG was given by intraperitoneal injection (80 mg/kg) 1 h after SAH. Neurological function were measured at 24 h after SAH. The expression of RIP3, NLRP3, ASC, and IL-1ß was measured by Western blot. Microthrombosis was detected by immunohistochemistry. RESULTS: Our results showed that the HSP90 protein level increased and peaked at 2 days after SAH. Microthrombosis caused by SAH was increased in 1 day and peaked at 2 days after SAH. Administration HSP90 specific inhibitor 17-AAG reduced expression of RIP3, NLRP3, ASC, and IL-1ß, reduced microthrombosis after SAH, and improved neurobehavior when compared to vehicle group. CONCLUSIONS: 17-AAG can ameliorate microthrombosis via HSP90/RIP3/NLRP3 pathway and improve neurobehavior after SAH.


Assuntos
Inibidores Enzimáticos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Hemorragia Subaracnóidea , Trombose , Animais , Córtex Cerebral , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP90 , Inflamação , Ratos , Ratos Sprague-Dawley , Proteína Serina-Treonina Quinases de Interação com Receptores , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/metabolismo , Trombose/tratamento farmacológico
4.
J Cell Physiol ; 235(2): 1001-1012, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31240707

RESUMO

Emerging evidence has indicated that long noncoding RNA (lncRNAs) play crucial roles in regulating thyroid cancer (TC) development. Linc00210 is a newly identified lncRNA which plays an oncogenic role in hepatocellular carcinoma and nasopharyngeal carcinoma, but whether Linc00210 can modulate the development of TC remains elusive. Here, we found that Linc00210 expression was upregulated in TC tissues compared to the matched noncancerous tissues. Overexpression of Linc00210 augmented the proliferation, migration, and invasion of TC cells. Mechanistically, Linc00210 served as a sponge for miR-195-5p, thereby counteracting its ability in downregulating the expression of IGF1R and the activation of PI3K/Akt signaling. Moreover, inhibition of Linc00210 suppressed the growth of TC cells in nude mice. Our findings for the first time uncovered the oncogenic property of Linc00210 in TC.

5.
Int J Cancer ; 146(2): 475-486, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31107971

RESUMO

Long noncoding RNAs (lncRNAs) promote cell proliferation, migration, invasion and castration resistance in prostate cancer (PCa). Understanding the inherited molecular mechanisms by which lncRNAs contribute to the progression of PCa to a lethal disease could have an important impact on cancer detection, diagnosis and prognosis. In our study, PCa-associated lncRNA transcripts from RNA-seq data were identified and screened via bioinformatics analysis, NCBI annotations and literature review. We identified a novel lncRNA, lncAPP (lncRNA activated in PCa progression), which activates in PCa progression and is expressed in primary tumor tissues and urine samples of patients with localized or advanced PCa. Urinary-based lncAPP is a promising biomarker for predicting PCa progression. In vitro and in vivo studies demonstrated that lncAPP enhanced cell proliferation and promoted migration and invasion. The underlying mechanism of lncRNA was investigated by RNA immunoprecipitation, dual-luciferase reporter system assay, etc. Upregulation of lncAPP promoted cell migration and invasion via competitively binding miR218 to facilitate ZEB2/CDH2 expression. In addition, in vivo subcutaneous tumor xenograft models and tail intravenously injection metastatic models were constructed to evaluate lncRNA function. Targeting lncAPP/miR218 axis in cell lines and tumor xenografts restrained tumor progression properties both in vitro and in vivo. These results establish that lncAPP/miR218 axis plays a critical role in PCa progression, and they also suggest new strategies to prevent tumor progression for therapeutic purposes.

6.
J Nanosci Nanotechnol ; 20(4): 2495-2502, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492267

RESUMO

A major reduction in energy consumption and the costs of catalysts will be required in future chemical manufacturing processes. To reach this goal, the transitional metal oxides (TMOs) as photocatalysts under solar energy have been widely studied. Nb2O5, as a promising photocatalyst, has attracted increasing attention owing to their unique properties. However, the intrinsic large bandgap of Nb2O5 hinder its potential applications in a variety of fields. Herein, we report an effective and simple strategy to synthesize black mesoporous Nb2O5-x nanorods (BMNb) with abundant oxygen vacancies. The formation of oxygen vacancy reduces the bandgap of Nb2O5 which extend the photoresponse from the ultraviolet to the visible and infrared light regions. In addition, The mesoporous structure of BMNb lead to a higher surface area than the as-prepared Nb2O5 precursor (36.24 m²/g cf 8.69 m²/g). Benefitting from coordinated regulation of structure and composition, the BMNb exhibits better photocatalytic performance than Nb2O5 in aerobic oxidative coupling of amines to imines under visible light irradiation at room temperature. The yield of BMNb for benzylamine oxidation increases by 63% over the Nb2O5. This work could open new perspectives to design TMOs with enhanced photocatalytic properties.

7.
Anal Biochem ; 588: 113468, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585097

RESUMO

Interleukin 6 (IL-6) is an interleukin that acts as both a proinflammatory and anti-inflammatory cytokine. It can be used as a potential diagnostic biomarker for sepsis. The aim of this study was to establish an easy-to-use detection kit for rapid, quantitative and on-site detection of IL-6. To develop the new IL-6 quantitative detecting kit, a double-antibody sandwich immunofluorescent assay was employed based on europium nanoparticles (Eu-np) combined with lateral flow immunoassay (LFIA). The performance of the new developed kit was evaluated in the aspects of parallel analysis, linearity, sensitivity, precision, accuracy, specificity and clinical sample analysis. Two-hundred and fourteen serum samples were used to carry out the clinical sample analysis. The new IL-6 quantitative detecting kit exhibited a wide linear range (2-500 pg/mL) and a good sensitivity (0.37 pg/mL). The intra-assay coefficient of variation (CV) and the inter-assay CV were 5.92%-8.87% and 7.59%-9.04%, respectively. The recovery rates ranged from 102% to 106%. Furthermore, a high correlation (n = 214, r = 0.9756, p < 0.01) was obtained when compared with SIEMENS CLIA IL-6 kit. Thus, the new quantitative method for detecting IL-6 has been successfully established. The results indicated that the newly-developed strip based on Eu-np combined with LFIA was a facile, fast, highly sensitive, low-cost, reliable biosensor and suitable for rapid and point-of-care test (POCT) for IL-6 in serum.

8.
Chemosphere ; 239: 124759, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518920

RESUMO

Ammonia is an important environmental stress factor in aquaculture. Long-term ammonia stress could affect the normal growth, and also increase the risk for the occurrence of various diseases. In order to learn the mechanism that ammonia caused the outbreak of the shrimp disease, transcriptomics and metabolomics approaches were used to analyze the differential expressions of the genes in hemocytes and different metabolites in the serum of the Pacific white shrimp Litopenaeus vannamei under ammonia exposure. Transcriptional analysis showed that 17 cell apoptosis related genes, seven phagocytosis related genes, 10 immunity related genes and seven cell cycle and lipid metabolism related genes showed differential expressions after ammonia exposure. Metabolomics analysis on the serum showed that 25 differential metabolites were identified in positive and negative ion patterns. They are involved in purine metabolism, amino acids metabolism and lipid metabolism. Injection of two up-regulated metabolites triethanolamine and oxypurinol to normal shrimp could induce apoptosis in normal shrimp. The total hemocytes counts in shrimp showed a significant decrease and the apoptotic cell ratio increased significantly under ammonia exposure. These results suggested that ammonia exposure increased the apoptosis of hemocytes, which affected the immunity of shrimp, and thus caused susceptibility to pathogenic infection. These data will help us understand the mechanism of ammonia stress leading to the immunity decline of shrimp.

9.
Carbohydr Polym ; 228: 115358, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635727

RESUMO

Following the main idea of a two-step method, microcrystalline cellulose is firstly pretreated to prepare regenerated cellulose (RC) with low crystallinity. Then, RC is continuously hydrolyzed to sugar in aqueous system by microwave driving. With the establishment of ZrO2 contained low acid catalytic system, an advanced route driven by microwave radiation to induce highly efficient hydrolysis of RC to sugar is formed. Due to the effect of ZrO2 on the molecular chain of cellulose, the recrystallization of RC is obviously weakened, and higher hydrolysis reactivity is achieved. Under the optimal conditions, the average conversion of RC and the yield of total reducing sugar highly reach 98.4 ±â€¯0.5% and 97.9 ±â€¯0.6%, respectively. The result is extremely superior to the efficiency of hydrolysis initiated only by pure acid. As a result, a novel and simple thinking to establish an advanced two-step methodology to hydrolyze cellulose to sugar with high efficiency is achieved.

10.
Gait Posture ; 76: 85-91, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31743872

RESUMO

BACKGROUND: Prosthetic alignment directly affects the biomechanical loading in individuals with lower-limb amputation, and improper alignment may be contribute to the high incidence of hip and knee osteoarthritis (OA). The biomechanical changes caused by different alignments should be considered in prosthetic fitting. However, the quantitative effect of alignment on the kinetic features of individuals with transfemoral amputation remains unclear. RESEARCH QUESTION: As important kinetics indexes, how are the hip and knee joint moments affected by prosthetic alignment in individuals with transfemoral amputation? METHODS: Gait tests of ten individuals with transfemoral amputation and fifteen individuals without amputation (control group) were performed. Several prosthetic alignment conditions were used, including the so-called "initial" alignment and eight malalignments. The hip and knee joint moments of the individuals with amputation under various alignments were analysed and compared with those of the control group. Statistical analyses were performed by one-way ANOVA, repeated measure multivariate ANOVA, and paired t tests. RESULTS: The peaks and impulses of the hip abductor and external rotator moments on the residual side were significantly smaller than those of the control group (P < 0.0056). The peaks of the hip extensor, adductor and external rotator moments on the intact side were significantly larger than those on the residual side (P < 0.05). Alignment significantly affected the intact hip and knee joint moments for each individual with amputation (P < 0.00625), but there was no consistent effect among individuals. SIGNIFICANCE: The significantly larger hip joint moment on the intact side of individuals with transfemoral amputation may be associated with the higher incidence of hip OA on the intact side. Alignment significantly affects the hip and knee joint moments of each individual with transfemoral amputation, but the individual responses to alignment changes are different. This situation may imply that the method for optimizing alignment should be personalized.

11.
Sci Adv ; 5(11): eaax9800, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31763456

RESUMO

Satellite observations of nitrogen dioxide (NO2) provide valuable information on the location and strength of NO x emissions, but spatial resolution is limited by horizontal transport and smearing of temporal averages due to changing wind fields. In this study, we map NO x emissions on high spatial resolution from TROPOMI observations of NO2 combined with wind fields based on the continuity equation. The divergence of horizontal fluxes proves to be highly sensitive for point sources like exhaust stacks. Thus, NO x emissions from individual power plants can be resolved and quantified even on top of considerably high urban pollution from the Saudi Arabian capital city Riyadh. This allows us to catalog NO x emissions from large point sources globally, as demonstrated for South Africa and Germany, with a detection limit of about 0.11 kg/s down to 0.03 kg/s for ideal conditions.

12.
J Agric Food Chem ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31702908

RESUMO

The increase in the incidence of antibiotic-resistant Staphylococcus aureus (S. aureus) associated infections necessitates the urgent development of novel therapeutic strategies and antibacterial drugs. Antivirulence strategy is an especially compelling alternative strategy due to its low selective pressure for the development of drug resistance in bacteria. Plants and microorganisms are not only important food and medicinal resources but also serve as sources for the discovery of natural products that target bacterial virulence factors. This review discusses the mechanisms of the major virulence factors of S. aureus, including the accessory gene regulator quorum-sensing system, bacterial biofilm formation, α-hemolysin, sortase A, and staphyloxanthin. We also provide an overview of natural products isolated from plants and microorganisms with activity against the major virulence factors of S. aureus and their adjuvant effects on existing antibiotics to overcome antibiotic-resistant S. aureus. Finally, the limitations and solutions of these antivirulence compounds are discussed, which will help in the development of novel antibacterial drugs against antibiotic-resistant S. aureus.

14.
Biosens Bioelectron ; 148: 111832, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31706173

RESUMO

Fluorescence-activated cell sorting (FACS) has rarely been applied to screening of microorganisms because of poor detection resolution, which is compromised by poor stability, toxicity, or interference from background fluorescence of the fluorescence sensors used. Here, a fluorescence-based rapid high-throughput cell sorting method was first developed using a fluorescence resonance energy transfer (FRET) fluorescent nanoprobe NP-RA, which was constructed by coating a silica nanoparticle with Rhodamine B and methyl-red (an azo dye). Rhodamine B (inner layer) is the FRET donor and methyl-red (outer layer) is the acceptor. This ready-to-use NP-RA is non-fluorescent, but fluoresces once the outer layer is degraded by microorganisms. In our experiment, NP-RA was ultrasensitive to model strain Shewanella decolorationis S12, showing a broad detection range from 8.0 cfu/mL to 8.7 × 108 cfu/mL under confocal laser scanning microscopy, and from 1.1 × 107 to 9.36 × 108 cfu/mL under a fluorometer. In addition, NP-RA bioimaging can clearly identify other azo-respiring cells in the microbial community, including Bosea thiooxidans DSM 9653 and Lysinibacillus pakistanensis NCCP-54. Furthermore, the fluorescent probe NP-RA is compatible with downstream FACS so that azo-respiring cells can be rapidly sorted out directly from an artificial microbial community. To our knowledge, no fluorescent nanoprobe has yet been designed for tracking and sorting azo-respiration functional microorganisms.

15.
Zootaxa ; 4608(3): zootaxa.4608.3.12, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31717141

RESUMO

Ceraeocercus Uvarov, 1910 of Tettigoniinae; Drymadusini is receded in China for the first time. Ceraeocercus fuscipennis fuscipennis Uvarov, 1910 is documented. Morphology and male calling songs are described and illustrations are provided.


Assuntos
Ortópteros , Distribuição Animal , Animais , China , Masculino
16.
Artigo em Inglês | MEDLINE | ID: mdl-31740599

RESUMO

From 2013 to 2017, with the implementation of the toughest-ever clean air policy in China, significant declines in fine particle (PM2.5) concentrations occurred nationwide. Here we estimate the drivers of the improved PM2.5 air quality and the associated health benefits in China from 2013 to 2017 based on a measure-specific integrated evaluation approach, which combines a bottom-up emission inventory, a chemical transport model, and epidemiological exposure-response functions. The estimated national population-weighted annual mean PM2.5 concentrations decreased from 61.8 (95%CI: 53.3-70.0) to 42.0 µg/m3 (95% CI: 35.7-48.6) in 5 y, with dominant contributions from anthropogenic emission abatements. Although interannual meteorological variations could significantly alter PM2.5 concentrations, the corresponding effects on the 5-y trends were relatively small. The measure-by-measure evaluation indicated that strengthening industrial emission standards (power plants and emission-intensive industrial sectors), upgrades on industrial boilers, phasing out outdated industrial capacities, and promoting clean fuels in the residential sector were major effective measures in reducing PM2.5 pollution and health burdens. These measures were estimated to contribute to 6.6- (95% CI: 5.9-7.1), 4.4- (95% CI: 3.8-4.9), 2.8- (95% CI: 2.5-3.0), and 2.2- (95% CI: 2.0-2.5) µg/m3 declines in the national PM2.5 concentration in 2017, respectively, and further reduced PM2.5-attributable excess deaths by 0.37 million (95% CI: 0.35-0.39), or 92% of the total avoided deaths. Our study confirms the effectiveness of China's recent clean air actions, and the measure-by-measure evaluation provides insights into future clean air policy making in China and in other developing and polluting countries.

18.
Thromb Haemost ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705517

RESUMO

INTRODUCTION: Impaired plasminogen activation (PA) is causally related to the development of lung fibrosis. Prior studies demonstrate that enhanced PA in the lung limits the severity of scarring following injury and in vitro studies indicate that PA promotes matrix degradation and fibroblast apoptosis. These findings led us to hypothesize that increased PA in an in vivo model would enhance the resolution of established lung fibrosis in conjunction with increased myofibroblast apoptosis. METHODS: Transgenic C57BL/6 mice with doxycycline inducible lung-specific urokinase plasminogen activator (uPA) expression or littermate controls were treated (day 0) with bleomycin or saline. Doxycycline was initiated on days 1, 9, 14, or 21. Lung fibrosis, stiffness, apoptosis, epithelial barrier integrity, and inflammation were assessed. RESULTS: Protection from fibrosis with uPA upregulation from day 1 through day 28 was associated with reduced parenchymal stiffness as determined by atomic force microscopy. Initiation of uPA expression beginning in the late inflammatory or the early fibrotic phase reduced stiffness and fibrosis at day 28. Induction of uPA activity in mice with established fibrosis decreased lung collagen and lung stiffness while increasing myofibroblast apoptosis. Upregulation of uPA did not alter lung inflammation but was associated with improved epithelial cell homeostasis. CONCLUSION: Restoring intrapulmonary PA activity diminishes lung fibrogenesis and enhances the resolution of established lung fibrosis. This PA-mediated resolution is associated with increased myofibroblast apoptosis and improved epithelial cell homeostasis. These studies support the potential capacity of the lung to resolve existing scar in murine models.

20.
J Cell Mol Med ; 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680470

RESUMO

Evidence demonstrates that M1 macrophage polarization promotes inflammatory disease. Here, we discovered that (R)-salbutamol, a ß2 receptor agonist, inhibits and reprograms the cellular metabolism of RAW264.7 macrophages. (R)-salbutamol significantly inhibited LPS-induced M1 macrophage polarization and downregulated expressions of typical M1 macrophage cytokines, including monocyte chemotactic protein-1 (MCP-1), interleukin-1ß (IL-1ß) and tumour necrosis factor α (TNF-α). Also, (R)-salbutamol significantly decreased the production of inducible nitric oxide synthase (iNOS), nitric oxide (NO) and reactive oxygen species (ROS), while increasing the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio. In contrast, (S)-salbutamol increased the production of NO and ROS. Bioenergetic profiles showed that (R)-salbutamol significantly reduced aerobic glycolysis and enhanced mitochondrial respiration. Untargeted metabolomics analysis demonstrated that (R)-salbutamol modulated metabolic pathways, of which three metabolic pathways, namely, (a) phenylalanine metabolism, (b) the pentose phosphate pathway and (c) glycerophospholipid metabolism were the most noticeably impacted pathways. The effects of (R)-salbutamol on M1 polarization were inhibited by a specific ß2 receptor antagonist, ICI-118551. These findings demonstrated that (R)-salbutamol inhibits the M1 phenotype by downregulating aerobic glycolysis and glycerophospholipid metabolism, which may propose (R)-salbutamol as the major pharmacologically active component of racemic salbutamol for the treatment of inflammatory diseases and highlight the medicinal value of (R)-salbutamol.

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