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1.
Medicine (Baltimore) ; 99(2): e18719, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914086

RESUMO

BACKGROUND: Hematoma expansion (HE) is related to clinical deterioration and unfavorable prognosis in intracerebral hemorrhage (ICH). Some studies have revealed that low serum magnesium level is associated with larger hematoma volume at admission, HE, and unfavorable outcomes. However, the conclusions remain unsettled. The purpose of this study is to evaluate the association between low serum magnesium level and HE by meta-analysis. METHODS: We will search the following electronic bibliographic databases: PubMed, Medline, Embase, Web of Science, and The Cochrane Library. Studies will be included if they reported a relationship of low serum magnesium level and HE, mortality or poor outcome. RESULTS: The results of this study will be submitted to a peer-reviewed journal for publication. CONCLUSION: This will be the first systematic review and meta-analysis to evaluate the association of HE following ICH with Hypomagnesemia. We look forward to the results will offer scientific proof to predict HE for ICH patients with low serum magnesium level. PROSPERO REGISTRATION NUMBER: This protocol has been registered in the PROSPERO network with number: CRD42019135995.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31916741

RESUMO

The development of high-performance electrode materials is of great significance for the next generation room temperature sodium-ion batteries. In this work, a new Na super-ionic conductor (NASICON) negative electrode, AgTi2(PO4)3, is prepared by a facile solid-state reaction and employed as sodium storage material for the first time. In situ X-ray diffraction during battery operation reveals an electrochemically Ag nanoparticle coating mechanism upon sodiation, facilitating the electron transfer in the complex. In addition, two steps of highly reversible biphasic transformation are observed. As a result, a reversible capacity of 214.9 mA h g-1 can be achieved, corresponding to the insertion/extraction of nearly four sodium ions. The AgTi2(PO4)3 electrode also demonstrates better kinetic properties than bare NaTi2(PO4)3 material. Such an "in situ" decorating method can open up a new direction for the design of NASICON-structured materials.

4.
Pest Manag Sci ; 76(1): 215-226, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31149772

RESUMO

BACKGROUND: Cuticle penetration plays an important role as a mechanism of insecticide resistance, but the underlying molecular mechanism remains poorly understood. In Blattella germanica, the cytochrome P450 gene, CYP4G19, is overexpressed in a pyrethroid-resistant strain. Here, we investigated whether CYP4G19 is involved in the biosynthesis of hydrocarbons and further contributes to cuticular penetration resistance in B. germanica. RESULTS: Compared with the susceptible strain, pyrethroid-resistant cockroaches showed lower cuticular permeability with Eosin Y staining. Removal of epicuticular lipids, mainly nonpolar hydrocarbons, with a hexane wash intensified the cuticular permeability and decreased the resistance index of the resistant strain. CYP4G19 was predominately expressed in the abdominal integument and could be upregulated by desiccation stress or short exposure to beta-cypermethrin. Overexpression of CYP4G19 in the resistant strain was positively correlated with a higher level of cuticular hydrocarbons (CHCs). RNAi-mediated knockdown of CYP4G19 significantly decreased its expression and caused a reduction in CHCs. Meanwhile, CYP4G19 suppression resulted in a non-uniform array of the lipid layer, enhanced cuticle permeability, and compromised insecticide tolerance. CONCLUSION: Our findings confirm that CYP4G19 is involved in hydrocarbon production and appears to contribute to hydrocarbon-based penetration resistance in B. germanica. This study highlights the lipid-based penetration resistance, advancing our understanding of the molecular mechanism underlying P450-mediated cuticular penetration resistance in insects. © 2019 Society of Chemical Industry.

5.
Chemosphere ; 240: 124896, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563716

RESUMO

Groundwater contaminated by hexavalent chromium (Cr(VI)) has posed severe threat to the environment and public health. Although heterotrophic bioremediation has been known as an efficient approach, little is explored on mineral nutrient source addition such as phosphorus minerals. In this study, the stabilization and sustainability of phosphorus minerals for providing phosphorus has been investigated, and the enhancement of Cr(VI) removal by mixed bacterial consortium coupled with phosphorus minerals was also observed and further verified, with 1.4-3.9 times K values (first-order) increase under different conditions. We demonstrated that the applied of phosphorus minerals facilitated the reduction of Cr(VI) and the removal of Cr(III), promoted the resistance of Cr(VI) and the generation of antioxidase, and engendered the evolution of microbial community structures and functional genes. These findings provide a new insight for enhancement of Cr(VI)-contaminated groundwater in-situ remediation.


Assuntos
Biodegradação Ambiental , Cromo/metabolismo , Fósforo/química , Poluentes Químicos da Água/metabolismo , Bactérias , Cromo/química , Água Subterrânea/química , Microbiota , Minerais , Oxirredução
6.
Biomed Microdevices ; 22(1): 10, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31875940

RESUMO

The organ-on-a-chip model mimics the structural and functional features of human tissues or organs and has great importance in translational research. For vessel-on-a-chip model, conventional fabrication techniques are unable to efficiently imitate the intimal-medial unit of the vessel wall. Bioprinting technology, which can precisely control the organization of cells, biomolecules, and the extracellular matrix, has the potential to fabricate three-dimensional (3D) tissue constructs with spatial heterogeneity. In this study, we applied the gelatin-methacryloyl-based bioprinting technology to print 3D construct containing endothelial cells (ECs) and smooth muscle cells (SMCs) on a microfluidic chip. Compared with traditional culture system, EC-SMC coculturing chip model upregulated αSMA and SM22 protein expression of the SMC to a greater degree and maintains the contractile phenotype of the SMC, which mimics the natural vascular microenvironment. This strategy enabled us to establish an in vitro vascular model for studies of the physiologic and pathologic process in vascular wall.

7.
Opt Express ; 27(23): 34247-34257, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878476

RESUMO

The influence of the high index ring layer (HIRL) in a tapered fiber Mach-Zehnder interferometer (MZI) on the interference observed, and thus on its potential applications in temperature sensing, has been investigated. The MZI was comprised of a tapered Ring Core Fiber (RCF), spliced between two single mode fibers (SMF). Since part of core mode from the SMF was converted into cladding modes in the RCF, due to the mismatch in the cores between the RCF and SMF, the residual power enters and then propagates along the center of the RCF (silica). The difference in phase between the radiation travelling along these different paths is separated by the HIRL to generate an interference effect. Compared with fiber interferometers based on core and cladding mode interference, the thin fiber HIRL is capable of separating the high order cladding modes and the silica core mode, under grazing incident conditions. Therefore, the optical path difference (OPD) and the sensitivity are both substantially improved over what is seen in conventional devices, showing their potential for interferometric temperature sensor applications. The optimum temperature sensitivity obtained was 186.6 pm/°C, which is ∼ 11.7 times higher than has been reported previously.

8.
Opt Express ; 27(24): 34603-34610, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878647

RESUMO

A micro-fiber Mach-Zehnder interferometer (MZI), with a thousands-µm-long ring-core fiber (RCF), is demonstrated, and its performance investigation is also implemented. In this paper, the proposed MZI is manufactured by ends-splicing the short RCF segment with single-mode fiber (SMF-28), respectively. The scheme of the MZI is a typically core-mismatch structure, which has the advantages of miniaturization and simplification. Due to the core mismatch between RCF and SMF, the light from the SMF can be well separated into ring core (RC) and silica center (SC) of the RCF at the first splicing point. After transmitting through the RC and SC, the two separated light beams encounter each other and interfere at the second splicing point. Different from conventional micro-fiber MZIs using SMFs or few-mode fibers, the RCF has a higher numerical aperture, which can generate a larger optical path-length difference with a short length fiber, accumulates a higher extinction ratio and suppresses the crosstalk between the core and cladding modes. Therefore, our proposed MZI is more stable and the best extinction ratios can reach up to 18.2 dB. Meanwhile, owing to the core structure of RCF (where SC is surrounded by high-index ring core), the power propagating through low-index area of RCF is mostly confined into SC (termed the silica-center modes). These characteristics would lead to the lower sensitivity to external disturbances.

9.
Chemosphere ; 245: 125571, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31881387

RESUMO

Double pollution with phosphorus (P) losses and potential lead (Pb) accumulation in rice fields could lead to eutrophication and crop toxicity, respectively, and affect people's health. To promote the sustainable and environmentally friendly development of agriculture, we conducted field experiments using a randomized block design to explore P losses, Pb accumulation and any potential association between P and Pb forms in rice-duck (RD) co-culture system and rice monoculture (RM) system combined with different fertilizers applied: the no fertilizer (RD and RM), chemical fertilizer (RDF and RMF), organic fertilizer (RDO and RMO), and a mixture of 70% chemical and 30% organic fertilizers (RDFO and RMFO) treatments with consistent P inputs. The results showed that RDFO had the best advantages in reducing the losses of TP (total phosphorous) (by 6.67%) and DRP (dissolved reactive phosphate) (32.72%) as well as the contents of available Pb (by 7.57%) and the accumulation of Pb in grains (26.32%) compared with RMF. RDFO also achieved the highest grain yield, reaching 10.97 t ha-1, and exhibited a lower soil weak-acid-extracted Pb (readily be taken up by plants) concentration than RDF and RMF. RDO resulted in greater TP leaching (increase by 10.62%) and lower DRP leaching (decrease by 36.57%) than RMF. It also exhibited the lowest concentration of weak-acid-extracted Pb and higher the concentration of grain Pb than that in other treatments. RDF reduced TP (by 5.33%) and DRP (by 16.36%) losses to a greater extent and the concentration of available and grain Pb were respectively 6.58% and 25.57% lower than RMF. Therefore, RDFO was the most recommended agricultural system for the studied region. Furthermore, different soil Pb forms were correlated with different P forms of soil and leakage and runoff water, which depended mainly on the fertilizer type and specific soil redox environment in the rice fields. The ratio of organic to inorganic fertilizer, the choice of organic fertilizer type, the assessment and timing of the detection of potential farmland pollution risks and association between different forms of P and Pb are worthy of further discussion.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31670685

RESUMO

Lung cancer postoperative complication prediction (PCP) is significant for decreasing the perioperative mortality rate after lung cancer surgery. In this paper we concentrate on two PCP tasks: (1) the binary classification for predicting whether a patient will have postoperative complications; and (2) the three-class multi-label classification for predicting which postoperative complication a patient will experience. Furthermore, an important clinical requirement of PCP is the extraction of crucial variables from electronic medical records. We propose a novel multi-layer perceptron (MLP) model called medical MLP (MediMLP) together with the gradient-weighted class activation mapping (Grad-CAM) algorithm for lung cancer PCP. The proposed MediMLP, which involves one locally connected layer and fully connected layers with a shortcut connection, simultaneously extracts crucial variables and performs PCP tasks. The experimental results indicated that MediMLP outperformed normal MLP on two PCP tasks and had comparable performance with existing feature selection methods. Using MediMLP and further experimental analysis, we found that the variable of "time of indwelling drainage tube" was very relevant to lung cancer postoperative complications.

12.
Nanomaterials (Basel) ; 9(11)2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31717446

RESUMO

:A plasmonic sensor based on a dual-side polished photonic crystal fiber operating in a telecommunication wavelength range is proposed and investigated numerically by the finite element method (FEM). We study the effects of structural parameters on the sensor's performance and analyze their tuning effects on loss spectra. As a result, two configurations are found when the analyte refractive index (RI) changes from 1.395 to 1.415. For configuration 1, an RI resolution of 9.39 × 10-6, an average wavelength sensitivity of 10,650 nm/RIU (the maximum wavelength sensitivity is 12,400 nm/RIU), an amplitude sensitivity of 252 RIU-1 and a linearity of 0.99692 are achieved. For configuration 2, the RI resolution, average wavelength sensitivity, amplitude sensitivity and linearity are 1.19 × 10-5, 8400 nm/RIU, 85 RIU-1 and 0.98246, respectively. The combination of both configurations can broaden the wavelength range for the sensing detection. Additionally, the sensor has a superior figure of merit (FOM) to a single-side polished design. The proposed sensor has a maximum wavelength sensitivity, amplitude sensitivity and RI resolution of the same order magnitude as that of existing sensors as well as higher linearity, which allows it to fulfill the requirements for modern sensing of being densely compact, amenable to integration, affordable and capable of remote sensing.

13.
Materials (Basel) ; 12(22)2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31717898

RESUMO

Lanthanide-doped hexagonal ß-NaYF4 crystals have received much attention in recent years due to their excellent photoluminescence properties. However, lanthanide-doped ß-NaYF4 crystals with micron and submicron scales as well as uniform morphology have received less attention. In this study, Eu3+-doped ß-NaYF4 (ß-NaYF4:Eu3+) crystals of micron and submicron size scales were synthesized using the solvothermal method with ethylene glycol as the solvent. The ß-NaYF4:Eu3+ crystals were highly crystallized. A comparison of the characteristics of the ß-NaYF4:Eu3+ crystals synthesized with and without the use of oleic acid as a surfactant was conducted. It was found that the utilization of oleic acid as a surfactant during their synthesis greatly decreased their particle size from micron to submicron scale, while adding a small amount of ethanol further reduced their particle size. In addition, they exhibited much smoother surfaces and more uniform morphologies, which were hexagonal prism bipyramids. The microstructural characteristics and photoluminescence properties of the ß-NaYF4:Eu3+ crystals were studied in detail. Results showed that ß-NaYF4:Eu3+ crystals prepared with the aid of oleic acid as a surfactant during their synthesis exhibited stronger photoluminescence.

14.
Sensors (Basel) ; 19(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775240

RESUMO

A hexagonal photonic crystal fiber (PCF) sensor with a dual optofluidic channel based on surface plasmon resonance (SPR) effect is proposed. The sensor characteristic is numerically explored by software integrated with the finite element method (FEM). The numerical results show that, when the analyte refractive index (RI) varies from 1.32 to 1.38, high linearity between resonance wavelength and analyte RI is obtained and the value of adjusted R2 is up to 0.9993. Simultaneously, the proposed sensor has maximum wavelength sensitivity (WS) of 5500 nm/RIU and maximum amplitude sensitivity (AS) of 150 RIU-1, with an RI resolution of 1.82 × 10-5 RIU. Besides, owing to a simple structure and good tolerance of the proposed sensor, it can be easily fabricated by means of existing technology. The proposed sensor suggests promising applications in oil detection, temperature measurement, water quality monitoring, bio-sensing, and food safety.

15.
Jpn J Clin Oncol ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31735973

RESUMO

BACKGROUND: This meta-analysis aimed to investigate the prognostic value of lymph node ratio in non-small-cell lung cancer. METHODS: We searched systematically for eligible studies in PubMed, Web of Science, Medline (via Ovid) and Cochrane library through 6 November 2018. The primary outcome was overall survival. Disease-free survival and cancer-specific survival were considered as secondary outcomes. Hazard ratio with corresponding 95% confidence interval were pooled. Quality assessment of included studies was conducted. Subgroup analyses were performed based on N descriptors, types of tumor resection, types of lymphadenectomy and study areas. Sensitivity analysis and evaluation of publication bias were also performed. RESULTS: Altogether, 20 cohorts enrolling 76 929 patients were included. Mean Newcastle-Ottawa Scale was 7.65 ± 0.59, indicating the studies' quality was high. The overall result showed non-small-cell lung cancer patients with lower lymph node ratio was associated with better overall survival (HR: 1.946; 95% CI: 1.746-2.169; P < 0.001), disease-free survival (HR: 2.058; 95% CI: 1.717-2.467; P < 0.001) and cancer-specific survival (HR: 2.149; 95% CI: 1.864-2.477; P < 0.001). Subgroup analysis prompted types of lymphadenectomy and the station of positive lymph node have an important effect on the prognosis. No significant discovery was found in sensitivity analysis. CONCLUSION: Patients with lower lymph node ratio was associated with better survival, indicating that lymph node ratio may be a promising prognostic predictor in non-small-cell lung cancer. The type of lymphadenectomy, an adequate examined number and the removed stations should be considered for more accurate prognosis assessment.

16.
Sci Total Environ ; 694: 133802, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756794

RESUMO

Airborne fungi are a primary component of bioaerosols and proved to impact human health and climatic change. Deoxyribonucleic acid (DNA) is the essential component of most living organisms with relatively stable physicochemical properties. Little is known about day-night and pollution-episode differences of DNA mass ratio and fungal community in fine particles (PM2.5) during serious winter haze events in China. Here we collected twenty-nine PM2.5 samples every day and night during an entire winter haze evolution process in a megacity of Central China, Wuhan. DNA extraction and high-throughput sequencing methods were adopted to analyze fungal community. Results showed that mass ratio of DNA in PM2.5 (RD/P %) changed with pollution process and showed significant negative correlations with PM2.5 concentration (r = -0.72, P < 0.05) and temperature (r = -0.74, P < 0.05). RD/P became lower (4.40 × 10-4%) after haze episodes than before (7.16 × 10-4%). RD/P of night-samples (1.98 × 10-4-4.97 × 10-4%) were all lower than those for day-samples (3.05 × 10-4-9.99 × 10-4%) for the same period. The fungal species richness became much lower (76 operational taxonomic units (OTUs)) after haze episodes than before (198 OTUs). The species richness of night-samples (119-537 OTUs) were all higher than those of day-samples (71-198 OTUs) for the same period. The OTUs specially owned by night-samples were also more than those by day-samples. Fungal community diversity showed random variations. The fungal community composition of each sample was classified from phylum to genus level. Pathogenic fungi accounted for 8.60% of the entire fungal community. The significantly enriched fungal taxa in the night-sample group (29 taxa) were also much more than that in the day-sample group (9 taxa), which could explain the higher species richness of airborne fungi community in the night during the haze evolution episodes. These findings may serve as an important reference or inspiration to other aerosol studies focusing on human health and behavior of aerosols in the atmosphere.

17.
Sci Total Environ ; : 135505, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31759719

RESUMO

Petrochemical industry (PI) is an important emission sector of anthropogenic volatile organic compounds (VOCs). The health impacts of VOCs from PI have caused a wide attention by both scientists and publics. In this study, compositions, sources and health risks of VOCs at a typical petrochemical industrial park along the middle reach of Yangtze River were studied. The total VOC concentrations were in the range of 5.59 to 541 ppbv with a mean value of 54.8 ppbv. Alkanes (41.4 ±â€¯15.7%) were the predominant group, followed by alkenes (19.9 ±â€¯18.3%), OVOCs (14.7 ±â€¯9.26%), halo hydrocarbon (11.2 ±â€¯6.42%), aromatics (8.17 ±â€¯5.08%), and acetylene (4.54 ±â€¯2.80%). Compound-specific health risk results showed that acrolein and 1,3-butadiene had the highest non-carcinogenic risk (expressed by hazard ratio, HR: 22.8) and carcinogenic risk (expressed by lifetime cancer risk, LCR: 6.7 × 10-3), respectively. Positive matrix factorization (PMF) model identified four VOC sources including fuel evaporation, industrial sources, ethylene industry and regional background with the average contributions of 35.6%, 12.0%, 26.5% and 25.9%, respectively. The receptor-originated approach combining the PMF model and conventional methods (HR and LCR) was used to assess the source-specific health risks. The non-cancer risks of four VOC sources were above safe level with regional background contributing most (38.3% or 4.91) to HR. The cancer risks of the four sources were below the tolerable level (<10-4) and regional background also contributed most, with relative contribution of 58.4% (or 10-4.22) to LCR. Our results are conductive to the formulation of countermeasures to reduce human exposure to ambient VOCs at petrochemical industrial parks in China.

18.
Chemosphere ; 243: 125283, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31760292

RESUMO

River sediment is the main internal pollution source of water body. This study evaluated the feasibility of electrochemical oxidation (EO) for polluted river sediment treatment. The hydrophilic and acute cytotoxicity (ACT) of dissolved organic matter (DOM) during electrolysis were mainly investigated. Meanwhile, the behavior of sediment evolution was also characterized. The results showed that the EO process was feasible for the treatment of polluted river sediment. The COD removal efficiency of polluted river sediment can achieve to 40.1% when the current density was 50 mA cm-2 with the chloride ion of 3000 mg L-1 and the initial pH of 8.5. The hydrophilicity of sediment DOM decreased with the decreasing molecule weight of humic-like substances, polar groups and the formation of aromatic aldehydes such as benzaldehyde. In this process, The ACT of sediment DOM can be reduced by the removal of aromatic compounds. In the process of electrolysis, the sediment particles were smaller than before, the dehydration was enhanced, and the crystal type tended to be stable, which was conducive to the utilization of resources. Therefore, EO method is a feasible alternative for the treatment of polluted river sediment.

19.
Eur J Med Chem ; : 111851, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31761381

RESUMO

Forty-eight analogues of CP-31398, an antitumor agent modulated the mutant p53 gene were synthesized and their cytotoxicities against four cancer cell lines with different p-53 status including bladder cell T24 (w-p53), gastric cell MGC-803 (m-p53), prostate cell DU145 (m-p53), prostate cell PC-3 (null-p53), lung cell A549 (w-p53) and normal liver cell line HL-7702 (w-p53) were examined. (E)-2-(4-Nitrostyryl)-4-(3-dimethylaminopropyl)-aminoquinazoline (10ah) was identified as the most potent compound in anti-proliferation against MGC-803 cells, with IC50 lowed to 1.73 µM, far potency than that of CP-31398. Molecular mechanism study revealed that 10ah and CP-31398 differ greatly in mechanism to exert their antitumor properties. 10ah could intercalate into DNA and resulted in significant DNA double-strand break. 10ah-treatment in MGC-803 cells increased the expression of p53, phosphorylated p53 (p-p53), CDK4, p21 to cause cell cycle arrest at G2/M phase, significantly up-regulated the levels of pro-apoptosis proteins Bak, Bax, Bim while down-regulated the anti-apoptosis proteins Bcl-2, Bcl-xL and the levels of cyclin B1, fluctuated the intracellular reactive oxygen species (ROS), Ca2+ and mitochondrial membrane potential, activated Caspase-9 and Caspase-3 to induce apoptosis. 10ah also displayed potent anticancer efficiency against MGC-803 xenograft tumors models, with tumor growth inhibition (TGI) up to 61.8% at 20 mg/kg without obvious toxicity.

20.
Materials (Basel) ; 12(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766381

RESUMO

For many optoelectronic applications, it is desirable for the lanthanide-doped phosphors to have broad excitation spectrum. The excitation mechanism of the lanthanide-doped YVO4, a high quantum efficient lasing material, primarily originates from the energy transfer process from the host VO43- complexes to the lanthanide ions, which has an excitation spectral bandwidth range of 230-330 nm. For applications in silicon solar cells, such phosphors can convert ultraviolet light to visible light for more efficient power generation, but this spectral range is still not broad enough to cover the entire ultraviolet spectrum of solar light. In this work, a novel core-shell and inorganic-organic hybridization strategy has been employed to fabricate Eu3+-doped YVO4 nanoparticles to broaden their photoluminescence excitation spectral bandwidth to the range of 230-415 nm, covering the entire ultraviolet spectrum of solar light and enabling their potential applications in silicon solar cells.

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