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1.
Clin Transl Gastroenterol ; 11(11): e00262, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33259161

RESUMO

OBJECTIVES: To establish and verify a simple noninvasive model based on the left gastric vein (LGV) to predict the grade of esophageal varices (EV) and high-risk EV (HEV), to facilitate clinical follow-up and timely treatment. METHODS: We enrolled 320 patients with B-viral cirrhosis. All patients underwent endoscopy, laboratory tests, liver and spleen stiffness (SS), and ultrasonography. HEV were analyzed using the χ test/t test and logistic regression in the univariate and multivariate analyses, respectively. EV grades were analyzed using the variance/rank-sum test and logistic regression. A prediction model was derived from the multivariate predictors. RESULTS: In the training set, multivariate analysis showed that the independent factors of different EV grades were SS, LGV diameter, and platelet count (PLT). We developed the LGV diameter-SS to PLT ratio index (LSPI) and LGV diameter/PLT models without SS. The area under the receiver operating characteristic curve of the LSPI for diagnosis of small EV, medium EV, large EV, and HEV was 0.897, 0.899, 0.853, and 0.954, respectively, and that of the LGV/PLT was 0.882, 0.890, 0.837, and 0.942, respectively. For the diagnosis of HEV, the negative predictive value was 94.07% when LSPI < 19.8 and the positive predictive value was 91.49% when LSPI > 23.0. The negative predictive value was 95.92% when LGV/PLT < 5.15, and the positive predictive value was 86.27% when LGV/PLT > 7.40. The predicted values showed similar accuracy in the validation set. DISCUSSION: Under appropriate conditions, the LSPI was an accurate method to detect the grade of EV and HEV. Alternatively, the LGV/PLT may also be useful in diagnosing the varices when condition limited.

2.
ACS Omega ; 5(23): 13482-13488, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32566813

RESUMO

Interfacial localization of solar thermal energy conversion to drive evaporation is a promising water treatment technology, especially for gaining pure water in freshwater-deficient areas. Phoenix tree bark is chosen as the raw material mainly because of its low cost and renewability. The carbonized bark with broadened pore sizes possess efficient steam escape channels and light absorption structure. The film with a double-layer structure is constructed through converting the surface of the bark into the carbonized structure under controllable laser treatment. The evaporation efficiency is calculated to be 74% under 1 sun by enhancing the photothermal conversion ability and efficiently opening the surface water transport channels simultaneously. The distillation water exhibits large resistance values (9.65 MΩ) and low concentrations of four primary ions (Na+, K+, Mg2+, and Ca2+), which achieves international standard for drinking water. In addition, the carbonized bark also exhibits all-right purified performance toward water evaporation from dye wastewater. The low cost and clean technology provides new inspiration for the future development of applicable solar thermal energy-driven water treatment systems.

3.
Front Oncol ; 9: 441, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31192137

RESUMO

Background: Although gemcitabine plus cisplatin (GP) is considered as standard chemotherapy for patients with advanced biliary tract cancer (BTC), the optimal regimen remains unknown. Methods: Using Network meta-analysis (NMA), a systematic review was conducted to find the most effective chemotherapy regimen for advanced BTC. We searched PubMed, Web of Science, Embase, Scopus and the Cochrane Library for articles published before October 6, 2018. Articles about chemotherapeutic comparisons were included. Hazard ratios (HRs) for overall survival (OS) and progression free survival (PFS) were estimated while odd ratios (ORs) was assessed for objective response rate (ORR). Results: The NMA included 25 studies and 3,312 individuals. Among all the regimens, Folfox-4 regimen obtained a superior difference in OS (BSC vs. Folfox-4, HR 3.4, 95% CI 1.7-6.7). XP was slightly better than GP in OS and GS approximately obtained the same efficacy to GP (HR for XP vs. GP 0.74, 95% CI 0.51-1.1; HR for GS vs. GP 1.1, 95% CI 0.71-1.5). Most of the targeted therapies included in this study tend to achieve better results in PFS and ORR but failed to improve OS, in which E-GEMOX achieved the best ORR when compared to BSC (OR 0.03, 95% CI 0.00-0.94). Conclusions: Folfox-4 regimen is likely to be the optimal chemotherapy for patients with advanced BTC and the predominant targeted therapy hasn't achieved significant success currently. XP and GS can be considered as alternatives for advanced BTC.

4.
J Ind Microbiol Biotechnol ; 46(6): 759-767, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30820723

RESUMO

α-Arbutin is an effective skin-whitening cosmetic ingredient and can be synthesized through hydroquinone glycosylation. In this study, amylosucrase (Amy-1) from Xanthomonas campestris pv. campestris 8004 was newly identified as a sucrose-utilizing glycosylating hydroquinone enzyme. Its kinetic parameters showed a seven-time higher affinity to hydroquinone than maltose-utilizing α-glycosidase. The glycosylation of HQ can be quickly achieved with over 99% conversion when a high molar ratio of glycoside donor to acceptor (80:1) was used. A batch-feeding catalysis method was designed to eliminate HQ inhibition with high productivity (> 36.4 mM h-1). Besides, to eliminate the serious inhibition caused by the accumulated hydroquinone oxidation products, the whole-cell catalysis was further proposed. 306 mM of α-arbutin was finally achieved with 95% molar conversion rate within 15 h. Hence, the batch-feeding whole-cell biocatalysis by Amy-1 is a promising technology for α-arbutin production with enhanced yield and molar conversion rate.


Assuntos
Arbutina/biossíntese , Glucosiltransferases/metabolismo , Hidroquinonas/metabolismo , Xanthomonas campestris/metabolismo , Biocatálise , Cosméticos , Glicosilação , Oxirredução
5.
Front Pharmacol ; 10: 139, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30873025

RESUMO

Background: Studies evaluating the prognostic significance of programmed death-ligand 1 (PD-L1) expression in colorectal cancer (CRC) are limited and remain controversial. This meta-analysis was conducted in order to evaluate the clinicopathological and prognostic significance of PD-L1 expression in CRC patients. Methods: A comprehensive search was performed against the Medline/PubMed, Embase, Cochrane Library, Web of Science (WoS) and Scopus databases. Data were extracted with name of the first author, year of publication, country of origin, tumor type, number of cases, staining method, cut-off values, PD-L1 positive expression, clinicopathological parameters, outcome, and quality assessment score, and statistical analysis was conducted using Review Manager Version 5.3 (Revman the Cochrane Collaboration; Oxford, England) and STATA version 14 (Stata Corporation; College Station, TX, USA). Results: Ten studies were included in this meta-analysis, in which the pooled hazard ratio (HR) showed that PD-L1 expression in tumor cells was significantly associated with a poor overall survival (HR = 1.50, 95% CI 1.05-2.13, P = 0.03). The pooled HR for disease-free survival (DFS) indicated that PD-L1 expression was significantly associated with shorter DFS (HR = 2.57, 95% CI 1.40-4.75, P = 0.002). The pooled odds ratios (ORs) showed that PD-L1 expression was associated with poor differentiation (OR = 3.47, 95% CI 1.37-8.77, P = 0.008) and right colon cancer (OR = 2.38, 95% CI 1.57-3.60, P < 0.0001). However, the expression of PD-L1 was independent of gender, age, tumor size, tumor stage, lymph node metastasis, and tumor-node metastasis stage. Conclusion: This meta-analysis indicated that a high level of PD-L1 expression might be a biomarker for a poor prognosis in CRC patients. This information may be helpful for clinicians to stratify CRC patients for anti-PD-1/PD-L1 therapy, particularly patients with microsatellite instability high (MSI-H).

6.
Sci Rep ; 9(1): 1781, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30742006

RESUMO

Bi2Se3 nanofilm has exhibited many promising potentials application in the field of photo-to-heat conversion. A highly-efficient photo-to-heat conversion system of Ag/Bi2Se3 composite nanofilm is successfully fabricated through laser direct writing (LDW) technique. The localized heat induced by laser simultaneously achieve Ag particles synthesis, transfer and patterning in a single processing step. The thermal reaction process includes the forming of nanoparticles based on the process of the thermal reduction, laser ablation, sputtering deposition and so on. The thermal storage capability and photothermal conversion stability have been greatly improved through preventing the heat from loss and efficient LSPR enhancing. The photothermal conversion mechanism of composition film is discussed in detail. This work suggests that the laser-assisted transfer technique give rise to a new expectation of functional composite nanofilm application for energy conversion.

7.
Phys Rev Lett ; 121(15): 150502, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30362796

RESUMO

Secret sharing is a conventional technique for realizing secure communications in information networks, where a dealer distributes to n players a secret, which can only be decoded through the cooperation of k (n/2

8.
PLoS One ; 13(4): e0196315, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689113

RESUMO

The ability to determine the origin of soybeans is an important issue following the inclusion of this information in the labeling of agricultural food products becoming mandatory in South Korea in 2017. This study was carried out to construct a prediction model for discriminating Chinese and Korean soybeans using Fourier-transform infrared (FT-IR) spectroscopy and multivariate statistical analysis. The optimal prediction models for discriminating soybean samples were obtained by selecting appropriate scaling methods, normalization methods, variable influence on projection (VIP) cutoff values, and wave-number regions. The factors for constructing the optimal partial-least-squares regression (PLSR) prediction model were using second derivatives, vector normalization, unit variance scaling, and the 4000-400 cm-1 region (excluding water vapor and carbon dioxide). The PLSR model for discriminating Chinese and Korean soybean samples had the best predictability when a VIP cutoff value was not applied. When Chinese soybean samples were identified, a PLSR model that has the lowest root-mean-square error of the prediction value was obtained using a VIP cutoff value of 1.5. The optimal PLSR prediction model for discriminating Korean soybean samples was also obtained using a VIP cutoff value of 1.5. This is the first study that has combined FT-IR spectroscopy with normalization methods, VIP cutoff values, and selected wave-number regions for discriminating Chinese and Korean soybeans.


Assuntos
Especiação Genética , Soja/química , Soja/classificação , China , Evolução Molecular , Análise de Fourier , Análise Multivariada , República da Coreia , Soja/genética , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Hepatol Commun ; 2(4): 376-392, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29619417

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of atherosclerotic cardiovascular disease. In our meta-analysis, we aimed to assess the correlation of NAFLD and four surrogate markers of subclinical atherosclerosis. PubMed, Embase, and the Cochrane Library were searched up until April 2017. Original studies investigating the association between NAFLD and subclinical atherosclerosis were included. The outcome data were extracted and pooled for the effect estimate by using a random-effects model. We used the Newcastle-Ottawa Quality Assessment Scale to assess the quality of the included studies. Of the 434 initially retrieved studies, 26 studies involving a total of 85,395 participants (including 29,493 patients with NAFLD) were included in this meta-analysis. The Newcastle-Ottawa Quality Assessment Scale scores suggested the included studies were of high quality. The pooled effects estimate showed that subjects with NAFLD exhibited a significant independent association with subclinical atherosclerosis compared to the non-NAFLD group (odds ratio, 1.60; 95% confidence interval, 1.45-1.78). Subgroup analysis suggested that the presence of NAFLD yielded a remarkable higher risk of increased carotid artery intima-media thickness/plaques, arterial stiffness, coronary artery calcification, and endothelial dysfunction with odds ratios (95% confidence interval) of 1.74 (1.47-2.06), 1.56 (1.24-1.96), 1.40 (1.22-1.60), and 3.73 (0.99-14.09), respectively. Conclusion: Our meta-analysis revealed a close link between NAFLD and subclinical atherosclerosis in light of four different indices. Patients with NAFLD might benefit from screening and surveillance of early atherosclerosis, which would facilitate the prediction of potential cardiovascular disease burden, risk stratification, and appropriate intervention in the long term. (Hepatology Communications 2018;2:376-392).

10.
Talanta ; 180: 120-126, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332789

RESUMO

A novel fluorescence method for the determination of hydrogen peroxide (H2O2) and uric acid (UA) was developed. The procedure was based on the hydroxyl radicals (·OH), which effectively quenched the fluorescence of the Mn2+-doped NaYF4:Yb,Er upconversion nanoparticles (UCNPs). Based on the property of Mn2+-doped NaYF4:Yb,Er upconversion nanoparticles, the Fenton reaction and enzymatic reaction of uric acid, this method could be used for highly sensitive detection of H2O2 and uric acid. Under optimal conditions, we observed that the fluorescence quenching signal showed good linearity with the H2O2 concentration in the range of 3.00×10-8 M ~ 6.00×10-5 M, and the detection limit of this assay was 1.30×10-8 M. Meanwhile, the linear concentration range for UA was 4.00×10-9 M ~ 1.00×10-5 M, and the lower limit of detection was 1.90×10-9 M. Furthermore, the developed method was successfully used for the determination of UA levels in human serum with satisfactory results.


Assuntos
Érbio/química , Corantes Fluorescentes/química , Fluoretos/química , Peróxido de Hidrogênio/química , Ferro/química , Manganês/química , Nanopartículas/química , Ácido Úrico/sangue , Ítrio/química , Humanos , Peróxido de Hidrogênio/análise , Limite de Detecção , Nanopartículas/ultraestrutura , Espectrometria de Fluorescência/métodos , Itérbio/química
11.
Eur J Gastroenterol Hepatol ; 30(6): 631-636, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29351115

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has been linked to an increased risk of cardiovascular disease (CVD). To explore the impact of diabetes mellitus (DM) as a cardiovascular risk factor, this meta-analysis quantitatively assessed the association of NAFLD and CVD in diabetic patients. METHODS: PubMed, EMBASE, and the Cochrane Library database were analyzed until the end of March 2017. Original studies analyzing the association between NAFLD and cardiovascular risk factors in the diabetic population were included. The available data related to outcome were extracted for the effect estimate using a random-effects model. The quality of the included studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. RESULTS: Of the 770 initially identified studies, 11 studies involving 8346 patients were finally included. The Newcastle-Ottawa Quality Assessment Scale scores suggested that the studies included were of high quality. The pooled effects estimate showed that diabetic patients with NAFLD showed a two times increased risk for CVD compared with patients without NAFLD (odds ratio=2.20, 95% confidence interval: 1.67-2.90). Subgroup analysis also yielded a markedly increased risk, with odds ratio (95% confidence interval) values of 2.28 (1.61-3.23) and 1.90 (1.48-2.45) in cross-sectional and cohort studies, respectively. CONCLUSION: This is the first meta-analysis investigating the relationship between NAFLD and CVD independent of the impact of DM. Our findings suggested that NAFLD increases the risk of CVD in populations with comparable DM profiles. Diabetic patients diagnosed with NAFLD might benefit from a more early cardiovascular risk assessment, thereby reducing CVD morbidity and mortality.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fatores Etários , Doenças Cardiovasculares/diagnóstico , Distribuição de Qui-Quadrado , Comorbidade , Diabetes Mellitus/diagnóstico , Feminino , Humanos , Estilo de Vida , Masculino , Análise Multivariada , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Razão de Chances , Prevalência , Prognóstico , Medição de Risco , Fatores de Risco , Fatores Sexuais
12.
Front Pharmacol ; 9: 1494, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30733677

RESUMO

Background: Programmed cell death ligand 1 (PD-L1) expression has been shown to correlate with poor prognosis in diverse human cancers. However, limited data exist on the prognostic and clinicopathologic significance of PD-L1 expression in prostate cancers (PCa), and the curative effect of anti-PD-1/PD-L1 therapy remains controversial. In this systematic review and meta-analysis, we aimed to evaluate the prognostic and clinicopathologic value of PD-L1 in PCa. Methods: We performed a systematic literature search in the PubMed, Cochrane Library, EMBASE, Web of Science, and SCOPUS databases up to July 21st, 2018. Pooled prevalence of PD-L1 in PCa was calculated using Freeman-Tukey double arcsine transformation by R software version 3.5.0. The data from the studies were examined by a meta-analysis using Review Manager software 5.3 to calculate pooled hazard ratios (HRs) and pooled odds ratios (ORs) with 95% confidence intervals (CIs) to estimate the prognostic and clinicopathologic value of PD-L1 in PCa. Heterogeneity was tested by the Chi-squared test and I 2 statistic. Results: Five studies with 2,272 patients were included in this meta-analysis. The pooled prevalence of PD-L1 in PCa was 35% (95% CI 0.32 to 0.37). Both PD-L1 expression (HR = 1.78; 95% CI 1.39 to 2.27; p < 0.00001) and PD-L1 DNA methylation (HR = 2.23; 95% CI 1.51 to 3.29; p < 0.0001) were significantly associated with poor biochemical recurrence-free survival (BCR-FS). PD-L1 tended to have high expression levels in high Gleason score cases (OR = 1.54; 95% CI, 1.17 to 2.03; P = 0.002) and androgen receptor-positive cases (OR = 2.42, 95% CI 1.31 to 4.50; P = 0.005). However, PD-L1 had relatively weak correlation with age, pathologic stage, lymph node metastasis and preoperative PSA level. Conclusions: This meta-analysis confirms the negative prognostic significance of PD-L1 expression and mPD-L1 in PCa patients. Additionally, PD-L1 has a statistically significant correlation with Gleason score and androgen receptor status, while the correlations with age, pathologic stage, lymph node metastasis, and preoperative PSA level were not statistically significant. However, the number of included studies is too small to make the conclusions more convincing, so more retrospective large-cohort studies are expected for the further confirmation of these findings.

13.
J Photochem Photobiol B ; 178: 568-576, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29258053

RESUMO

Excessive exposure to ultraviolet (UV) B radiation may lead to skin damage, photosensitivity, or even tumorigenesis via induction of oxidative stress. Naturally derived antioxidants could play significant roles in cancer therapy due to their multi-targeted actions and lack of substantial toxicity. Drug combinations target at diverse pathway of cells and make cells export meticulous biological outcomes through the multifaceted signaling network. The UVB protective effects of combinations of naturally derived antioxidants- curcumin, resveratrol, proanthocyanidins, baicalein, and beta-nicotinamide adenine dinucleotide (NADH) were investigated. An oxidative cell damage model was established to study the ultraviolet irradiation system. An orthogonal array composite design (OACD) was employed in the optimization of antioxidants combinations. Combination of resveratrol (0.1µM) and baicalein in medium concentration (0.2µM), with NADH in high concentration (0.8µM) was found to be the most efficacious combination among all the 30 runs performed using OACD. The findings suggested that UVB exposure-inflicted cell apoptosis can be significantly reduced by naturally-derived antioxidant combinations. These results provide an insight into the discovery of synergistic antioxidant combinations in skin cancer, using orthogonal array composite design (OACD). The results also have practical implications in the understanding of drug mechanisms in skin cancer, which can assist clinical practice by recommending better drug combinations.


Assuntos
Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Raios Ultravioleta , Antioxidantes/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Curcumina/química , Curcumina/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Fragmentação do DNA/efeitos da radiação , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Flavanonas/química , Flavanonas/farmacologia , Humanos , Modelos Lineares , Estresse Oxidativo/efeitos da radiação , Proantocianidinas/química , Proantocianidinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Resveratrol , Pele/citologia , Estilbenos/química , Estilbenos/farmacologia
14.
PLoS One ; 12(11): e0187622, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29099862

RESUMO

In this study, the effects of coronatine treatment on the growth, comprehensive metabolic profiles, and productivity of bioactive compounds, including phenolics and phytosterols, in whole plant cultures of Lemna paucicostata were investigated using gas chromatography-mass spectrometry (GC-MS) coupled with multivariate statistical analysis. To determine the optimal timing of coronatine elicitation, coronatine was added on days 0, 23, and 28 after inoculation. The total growth of L. paucicostata was not significantly different between the coronatine treated groups and the control. The coronatine treatment in L. paucicostata induced increases in the content of hydroxycinnamic acids, such as caffeic acid, isoferulic acid, ρ-coumaric acid, sinapic acid, and phytosterols, such as campesterol and ß-sitosterol. The productivity of these useful metabolites was highest when coronatine was added on day 0 and harvested on day 32. These results suggest that coronatine treatment on day 0 activates the phenolic and phytosterol biosynthetic pathways in L. paucicostata to a greater extent than in the control. To the best of our knowledge, this is the first report to investigate the effects of coronatine on the alteration of metabolism in L. paucicostata based on GC-MS profiling. The results of this research provide a foundation for designing strategies for enhanced production of useful metabolites for pharmaceutical and nutraceutical industries by cultivation of L. paucicostata.


Assuntos
Aminoácidos/farmacologia , Araceae/crescimento & desenvolvimento , Araceae/metabolismo , Indenos/farmacologia , Araceae/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas
15.
Sci Rep ; 6: 33743, 2016 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-27642100

RESUMO

Antidiabetic medication may modify the incidence of hepatocellular carcinoma (HCC). We aimed to compare the use of different antidiabetic strategies and the incidence of HCC. PubMed, Embase.com and Cochrane Library databases were searched up to 31 October 2015 and randomized controlled trials (RCTs), cohort studies or case-control studies were included for our analyses. A total of thirteen studies enrolling 481358 participants with 240678 HCC cases who received at least two different strategies were retrieved in this analysis. Direct comparisons showed that use of metformin (risk ratio [RR] 0.49, 95% CI 0.25-0.97) was associated with a significant risk reduction of HCC, while insulin (RR = 2.44, 95% CI 1.10- 5.56) may significantly increase the risk. Indirect evidence also suggested that insulin (RR = 2.37, 95% CI 1.21-4.75) was associated with a significantly increased risk of HCC. Additionally, metformin was effective in reducing the risk of HCC when compared with sulphonylurea (RR = 0.45, 95% CI 0.27-0.74) and insulin (RR = 0.28, 95% CI 0.17-0.47). Notably, metformin was hierarchically the best when compared with other antidiabetic therapies for the prevention of HCC. In summary, available evidence suggests that metformin was the most effective strategy to reduce HCC risk when compared with other antidiabetic interventions.


Assuntos
Carcinoma Hepatocelular , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Neoplasias Hepáticas , Metformina/uso terapêutico , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/prevenção & controle , Feminino , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/prevenção & controle , Masculino , Fatores de Risco
16.
Huan Jing Ke Xue ; 37(3): 816-24, 2016 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-27337871

RESUMO

In January 2013 large-scale, continuous and severe haze occurred in Nanjing. Three-wavelength photoacoustic soot spectrometer (PASS-3) was used for real-time, online and situ measurements of aerosol absorption and scattering coefficients in the northern suburb of Nanjing during January 2013. The results indicated that the average aerosol absorption and scattering coefficients were (83.20 ± 35.24) Mm⁻¹ and (670.16 ± 136.44) Mm⁻¹ during haze days, which were 3.85 and 3.45 times higher than those on clean days, respectively. The diurnal variation of absorption and scattering coefficients showed a bimodal distribution. The mean single scattering albedo and scattering Angstrom exponent were (0.89 ± 0.04) and (1.30 ± 0.27) respectively, indicating the predominance of scattering fine particles during haze days in Nanjing. Aerosols could be significantly removed by precipitation. The absorption and scattering coefficients showed negative correlations with surface wind speed, and the single scattering albedo and Angstrom exponent showed positive correlations with wind speed. Aerosol scattering coefficient was highest under southeasterly wind, whereas the absorption coefficient was highest under the southwesterly wind. In the three haze pollution events, Haze 1 and Haze 2 were mainly affected by long-range transportation of pollutants. Haze 1 was mainly affected by aging air mass from north Nanjing, Haze 2 was mainly affected by biomass burning air mass from southwest Nanjing, while Haze 3 was mainly caused by the high sulfate.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Biomassa , China , Tamanho da Partícula , Fuligem/análise , Sulfatos/análise , Vento
17.
J Environ Sci (China) ; 40: 35-43, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26969543

RESUMO

The optical properties of aerosol as well as their impacting factors were investigated at a suburb site in Nanjing during autumn from 14 to 28 November 2012. More severe pollution was found together with lower visibility. The average scattering and absorption coefficients (Bsca and Babs) were 375.7 ± 209.5 and 41.6 ± 18.7 Mm(-1), respectively. Higher Ångström absorption and scattering exponents were attributed to the presence of more aged aerosol with smaller particles. Relative humidity (RH) was a key factor affecting aerosol extinction. High RH resulted in the impairment of visibility, with hygroscopic growth being independent of the dry extinction coefficient. The hygroscopic growth factor was 1.8 ± 1.2 with RH from 19% to 85%. Light absorption was enhanced by organic carbon (OC), elemental carbon (EC) and EC coatings, with contributions of 26%, 44% and 75% (532 nm), respectively. The Bsca and Babs increased with increasing N100 (number concentration of PM2.5 with diameter above 100 nm), PM1 surface concentration and PM2.5 mass concentration with good correlation.


Assuntos
Aerossóis/análise , Aerossóis/química , Poluentes Atmosféricos/química , Poluentes Atmosféricos/análise , Carbono/análise , China , Monitoramento Ambiental/métodos , Umidade , Fenômenos Ópticos , Tamanho da Partícula , Material Particulado/análise , Molhabilidade
18.
Oncotarget ; 7(16): 21753-62, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943041

RESUMO

OBJECTIVES: Usage of statins is suggested to decrease the incidence of HCC. When it comes to different statin subtypes, the chemopreventive action remains controversial. We aim to compare the usage of different statins and reduction of HCC risk. METHODS: We searched PubMed, Embase.com and Cochrane Library database up to August 10, 2015. Duplicated or overlapping reports were eliminated. We performed a traditional pair-wise meta-analysis and a Bayesian network meta-analysis to compare different treatments with a random-effects model. RESULTS: We reviewed five observational studies enrolling a total of 87127 patients who received at least two different treatment strategies including rosuvastatin, atorvastatin, simvastatin, pravastatin, fluvastatin, cerivastatin, and lovastatin or observation alone. Direct comparisons showed that usage of atorvastatin (OR 0.63, 95%CI 0.45-0.89) and fluvastatin (OR 0.58, 95%CI 0.40-0.85) could significantly cut the risk of liver cancer. The difference of indirect comparisons between the included regimens is not statistically significant. However, usage of all types of statins, such as fluvastatin (RR 0.55, 95%CI 0.26-1.11), atorvastatin (RR 0.59, 95%CI 0.30-1.16), simvastatin (RR 0.69, 95%CI 0.38-1.25), cerivastatin (RR 0.71, 95%CI 0.19-2.70), pravastatin (RR 0.72, 95%CI 0.37-1.45), lovastatin (RR 0.81, 95%CI 0.34-1.96) and rosuvastatin (RR 0.92, 95%CI 0.44-1.80), appeared to be superior to observation alone. Notably, fluvastatin was hierarchically the best when compared with the six other statins. CONCLUSIONS: Our analyses indicate the superiority of usage of statins in reduction of liver cancer. Available evidence supports that fluvastatin is the most effective strategy for reducing HCC risk compared with other statin interventions.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Fígado/efeitos dos fármacos , Atorvastatina/uso terapêutico , Teorema de Bayes , Quimioterapia Combinada , Ácidos Graxos Monoinsaturados/uso terapêutico , Fluvastatina , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/classificação , Indóis/uso terapêutico , Fígado/patologia , Lovastatina/uso terapêutico , Estudos Observacionais como Assunto , Pravastatina/uso terapêutico , Piridinas/uso terapêutico , Rosuvastatina Cálcica/uso terapêutico , Sinvastatina/uso terapêutico , Resultado do Tratamento
19.
Huan Jing Ke Xue ; 36(6): 1926-34, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26387291

RESUMO

To investigate the characteristics of water-soluble ions in PM2.5 and their contribution to light extinction in haze days, on-line monitoring of PM2.5. was conducted at North Suburban Nanjing from 25 January through 3 February, 2013. Water-soluble components were collected with a particle-into-liquid sampler (PILS), and analyzed by ion chromatography (IC) for the contents of SO4(2-), NO3-, NH4+, Cl-, Na+, K+, Mg2+ and Ca2+ Simultaneously particle size distributions were measured using scanning mobility particle sizer (SMPS) and Aerodynamic Particle Sizer (APS). The absorption and scattering coefficients were measured by three-wavelength photoacoustic soot spectrometer (PASS-3). Trace gases (SO2, NO2 etc.) were also monitored. The results showed that the average concentrations of total water-soluble ions were 70.3 and 22.9 microg x m(-3) in haze and normal days, respectively. Secondary hygroscopic components including SO4(2-), NO3- and NH4+ were the major ionic pollutants. Hazy days favored the conversion of SO2 and NOx, to SO4(2-) and NO3-, respectively, and in particular the oxidation of NOx. Using multiple linear regression statistical method, the empirical relationship between the dry aerosol extinction coefficient and the chemical composition was established. NH4NO3 was found to be the largest contributor to aerosol extinction in winter in Nanjing, followed by (NH4)2SO4, OC and EC. In two heavy pollution events, the increase of ion concentrations was influenced by the increase of primary emissions and secondary transformation.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Aerossóis , China , Cidades , Monitoramento Ambiental , Gases , Íons , Luz , Tamanho da Partícula , Estações do Ano , Solubilidade , Água
20.
Sci Rep ; 5: 11132, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-26047357

RESUMO

The non-measurement based coherent feedback control (CFC) is a control method without introducing any backaction noise into the controlled system, thus is specially suitable to manipulate various quantum optical systems for preparing nonclassical states of light. By simply tuning the transmissivity of an optical controller in a CFC loop attached to a non-degenerate optical parametric amplifier (NOPA), the quantum entanglement degree of the output optical entangled state of the system is improved. At the same time, the threshold pump power of the NOPA is reduced also. The experimental results are in reasonable agreement with the theoretical expectation.

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