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1.
Artigo em Inglês | MEDLINE | ID: mdl-31592881

RESUMO

BACKGROUND: Single-incision laparoscopic right hemicolectomy (SILS) has been promoted in clinic since 2008, but a systematic review of comparing SILS and traditional laparoscopic right hemicolectomy (TLS) with long-term follow-up is rare. Here, in this study, comparison of SILS and TLS with long-term follow-up was evaluated by a meta-analysis method. METHODS: All studies about SILS and TLS for right hemicolectomy from 2010 to 2018 were searched from databases including Medline, Embase, Cochrane Library, and Wanfang. Operation index, recovery, and midterm follow-up data were evaluated by fixed-effects models, random-effects models, and Begg test. RESULTS: We collected 22 studies with 2218 patients. SILS groups contained 1038 (46.7%) patients, and 1180 (53.3%) patients were observed in the TLS group. Patients' baseline data were similar in the 2 groups. Compared with TLS, SILS had shorter operation duration [standardized mean difference (SMD): -0.35, 95% confidence interval (CI): -0.61 to -0.08, P<0.001, χ=49.40], shorter hospitalization time (SMD: -0.27, 95% CI: -0.37 to -0.16, P<0.001, χ=9.17), slightly less blood loss (SMD: -0.23, 95% CI: -0.36 to -0.10; P<0.001; χ=5.36), and smaller incision length (SMD: -2.19, 95% CI: -3.66 to -0.71, P<0.001; χ=316.1). No statistical differences were observed in other figures. CONCLUSION: SILS is more convenient and has better efficacy than TLS and could provide a promising surgical approach for right colon diseases.

2.
Crit Rev Food Sci Nutr ; : 1-23, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31547671

RESUMO

Lignin is the second most abundant biorenewable polymers only next to cellulose and is ubiquitous in various plant foods. In food industry, lignin often presented as a major component of by-products from plant foods. In the last decade, the food and nutritional interests of lignin attracted more and more attentions and great progresses have been accomplished. In the present review, the structure, physicochemical properties, dietary occurrence and preparation methods of lignin from food resources were summarized. Then, the versatile activities of food lignin were introduced under the subtitles of antioxidant, antimicrobial, antiviral, antidiabetic and other activities. Finally, the potential applications of food lignin were proposed as a food bioactive ingredient, an improver of food package films and a novel material in fabricating drug delivery vehicles and contaminant passivators. Hopefully, this review could bring new insights in exploiting lignin from nutrition- and food-directed views.

3.
J Colloid Interface Sci ; 557: 227-235, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31521972

RESUMO

TiO2-mediated photoelectrocatalysis is emerging as a promising way to degrade refractory contaminates. Nevertheless, the concrete application of TiO2 is seriously limited because of its poor conductivity, unexpected recombination of photoinduced charges, and broad bandgap (3.2 eV). In this work, two-dimensional (2D) TiO2-g-C3N4 with both TiN and CO bridges is successfully constructed and assembled with carbon fibers to realize efficient photoelectrochemical (PEC) pollutant degradation. Density functional theory (DFT) calculations suggest that the generated interface heterojunction of 2D TiO2-g-C3N4 can provide quick charge separation and transfer via both TiN and CO bridges, resulting in a prepared catalyst that can facilitate the effective separation and transportation of photoinduced electron-hole pairs. In addition, according to electrochemical impedance spectroscopy, the 2D TiO2-g-C3N4 composition with the generated interface heterojunction reduces internal resistance and becomes more conducive to electrocatalysis compared with pure TiO2 or g-C3N4. Using bisphenol A (BPA) as a typical refractory contaminate, the 2D TiO2-g-C3N4/carbon fiber electrode exhibits a higher PEC activity, with reaction rates 1.7, 2.5, and 3 times faster than that of g-C3N4, TiO2, and commercial P25, respectively. Furthermore, the greatest BPA degradation of the PEC system is much higher than the sum of the photocatalytic (PC) and electrocatalytic (EC) systems. Additionally, the enhanced activities of electrocatalysis and photocatalysis for the degradation of BPA is attributed to the collaboration of the interfacial effect and excellent electrical conductivity derived from the 2D structure of the TiO2-g-C3N4 heterojunction. This study proposes a new tactic for the design and construction of photoelectrocatalysts via a synergistic interfacial effect to improve the photocatalytic and electrocatalytic degradation activities for refractory pollutants.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31553556

RESUMO

Photoelectrocatalytic (PEC) reduction and removal of atrazine, one typical endocrine disruptor chemical, was achieved on Pd quantum dots modified TiO2 nanotubes (PdQDs@TiO2NTs) under regulating potentials. Compared with that on TiO2NTs, the PEC reduction efficiency of atrazine on PdQDs@TiO2NTs significantly increased, mainly attributed to the reduced electron transfer resistance, longer lifetime of the photogenerated electrons and the faster electron injection from the catalyst to atrazine in the solution. Meanwhile, PdQDs could also function as cocatalyst so that the electrocatalytic activity of PdQDs@TiO2NTs was evidently improved. Moreover, the investigation indicated that the applied potential not only played important role in accelerating the separation of photogenerated electrons and holes, but also with the increment of the cathodic potential, the PEC reduction mechanism of atrazine underwent the variation of electro-assisted photocatalysis, synergetic photoelectro-catalysis, and photoassisted electro-catalysis. A highest atrazine PEC reduction efficiency was achieved as 99.5% on PdQDs@TiO2NTs in about 5 h under the potential of -1.3 V vs. SCE, whereas the highest synergetic effect of photo- and electro- catalysis was achieved at a lower potential of -0.9 V vs. SCE.

5.
J Hazard Mater ; 382: 121017, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31446350

RESUMO

Enhanced and selective photocatalytic oxidation of nonylphenol (NP), a typical hydrophobic endocrine disrupting chemicals (EDCs), was realized on hydrophobic titanium dioxide nanotubes (H-TiO2NTs), which was fabricated by an electrochemical anodization method, followed by grafting of perfluorooctyl groups. The water contact angle of catalyst surface changed from 21.1° to 128.4° after hydrophobic modification. H-TiO2NTs showed excellent photocatalytic oxidation performance for NP, that it was completely converted in 40 min under irradiation, which was improved for about 17% compared with the hydrophilic TiO2NTs. The enhanced photocatalytic performance of H-TiO2NTs was attributed to the stronger adsorption ability toward NP identified by ATR-FTIR, with an initial adsorption rate of 4 times as higher as that of bare TiO2NTs. Meanwhile, the hydrophobic surface of H-TiO2NTs was beneficial for generation of more hydroxyl radicals. The apparent rate constant of hydroxyl radicals' generation on H-TiO2NTs, which was the main oxidizing species, could reach 1.83 times that of the hydrophilic TiO2NTs. Both the two factors contributed to the successful competition of NP against the coexistent hydrophilic contaminates in the adsorption and oxidation on the catalyst surface, leading to the selective removal of NP in mixed systems finally.

6.
BMC Plant Biol ; 19(1): 287, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262258

RESUMO

BACKGROUND: The majority of apricot (Prunus armeniaca L.) cultivars display orange or yellow background skin, whereas some cultivars are particularly preferred by consumers because of their red blushed skin on the background. RESULTS: In this study, two blushed ('Jianali' and 'Hongyu') and two nonblushed ('Baixing' and 'Luntaixiaobaixing') cultivars were used to investigate the formation mechanism of blushed skin in apricots. High-performance liquid chromatography (HPLC) analysis showed that the blushed cultivars accumulated higher cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside and peonidin-3-O-rutinoside levels during fruit ripening than the nonblushed cultivars. Based on coexpression network analysis (WGCNA), a putative anthocyanin-related R2R3-MYB, PaMYB10, and seven structural genes were identified from transcriptome data. The phylogenetic analysis indicated that PaMYB10 clustered in the anthocyanin-related MYB clade. Sequence alignments revealed that PaMYB10 contained a bHLH-interaction motif ([DE]Lx2[RK]x3Lx6Lx3R) and an ANDV motif. Subcellular localization analysis showed that PaMYB10 was a nuclear protein. Real-time qRT-PCR analysis demonstrated that the transcript levels of PaMYB10 and seven genes responsible for anthocyanin synthesis were significantly higher in blushed than in nonblushed apricots, which was consistent with the accumulation of anthocyanin. In addition, bagging significantly inhibited the transcript levels of PaMYB10 and the structural genes in 'Jianali' and blocked the red coloration and anthocyanin accumulation. Transient PaMYB10 overexpression in 'Luntaixiaobaixing' fruits resulted in the red blushed skin at the maturation stage. CONCLUSIONS: Taken together, these data reveal that three anthocyanins are responsible for the blushed skin of apricots, identify PaMYB10 as a positive regulator of anthocyanin biosynthesis in apricots, and demonstrate that blush formation depends on light.


Assuntos
Antocianinas/biossíntese , Regulação da Expressão Gênica de Plantas , Pigmentos Biológicos/biossíntese , Proteínas de Plantas/genética , Prunus armeniaca/fisiologia , Fatores de Transcrição/genética , Sequência de Aminoácidos , Antocianinas/genética , Cromatografia Líquida de Alta Pressão , Cor , Frutas/genética , Frutas/fisiologia , Glucosídeos/biossíntese , Glucosídeos/genética , Filogenia , Pigmentos Biológicos/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Prunus armeniaca/genética , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
7.
Analyst ; 144(16): 4841-4847, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31290489

RESUMO

Polychlorinated biphenyl (PCB) detection in the environment is significant for both environmental protection and human health. Herein, a highly sensitive aptamer sensor has been established by employing a 2,3',5,5'-tetrachlorobiphenyl (PCB72) targeting aptamer as a highly specific recognition element and a gold/silver (Au@Ag) nanocomposite as the surface-enhanced Raman spectroscopy (SERS) substrate for detecting environmental PCB72. The Au@Ag nanoparticles (NPs) exhibit a strong SERS enhancement and provide an efficient substrate for immobilizing the PCB72 aptamer and Raman signal labelled molecule, 4-mercaptobenzoic acid (4-MBA). The targeted PCB72 could competitively bind with the PCB72 aptamer, resulting in a few aptamers sticking to the Au@Ag NPs and the "hot spot" strengthening effect of the substrate. Under optimal conditions, this aptamer sensor exhibits great performance with high sensitivity, excellent selectivity and stability for the monitoring of PCB72, which shows an excellent linear correlation ranging from 1 to 1000 pg mL-1 with a limit of detection of 0.3 pg mL-1. Furthermore, this aptamer assay exhibits high specificity and selectivity for PCB72 with the detection error of less than 0.27 for other PCBs and 0.21 for other interfering species, even if the coexisting interferents are 100-fold concentration in the system. Additionally, the recognition mechanism of the binding of aptamers to PCB72 is analyzed via UV-vis spectroscopy and molecular docking simulations, which suggest that PCB72 could insert into the aptamers. Furthermore, this method is successfully utilized for PCB72 detection in real water samples with a simple pre-treatment. In general, this work provides a new and effective method using an environmental aptamer sensor for rapid and sensitive PCB72 detection.

8.
Biosens Bioelectron ; 140: 111352, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31163397

RESUMO

Atrazine (ATZ) is one of the most widely used and highly toxic triazine herbicides in the world. Photoelectrochemical (PEC) method is an attractive and sensitive alternate for ATZ. However, for conventional PEC sensors, recognition elements usually need to immobilize on electrode surface, where a complex procedure is unavoidable and the reproducibility of sensors fabrication is usually poor. Therefore, we herein proposed a new and feasible strategy for developing a signal-on immobilization-free PEC aptasensor to ATZ. Aptamer for ATZ is combined with graphene to obtain APT-GN complex, serving as the recognition element in solution. TiO2 nanotubes (NTs) electrode deposited with Au nanoparticles (NPs) is used as the substrate electrode. After further self-assembled with 1-Mercaptooctane (MCT), the photo-generated carriers transfer between the resultant electrode and the electrolyte will be blocked, leading to a signal-off of the photocurrent. But when sensing ATZ, aptamers on APT-GN will be grasped by ATZ, leaving free graphene to assemble onto MCT/Au NPs/TiO2 NTs, which will largely "turn on" the photocurrent response of the substrate electrode due to the efficient carrier transport efficiency of graphene. Meanwhile, simultaneous addition of deoxyribonuclease I (DNase I) can bring about further cycling amplification of the signal enhancement. The as-designed PEC aptasensor exhibits a linear range from 50.0 fM to 0.3 nM with detection limit of 12.0 fM for ATZ. Since the reaction of recognition elements and targets ATZ occurs in homogeneous solution rather than on the photoelectrode surface, this PEC aptasensor exhibits advantages of high stability, anti-interference ability, reproducibility, and wide pH and ion strength feasibility range. A promising immobilization-free aptasensing platform has thus been provided not only for ATZ but also for other kinds of environmental pollutants.

9.
J Agric Food Chem ; 67(26): 7416-7427, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31180666

RESUMO

The core-shell structured micelles from octenylsuccinated oat ß-glucan (OSßG) are able to solubilize ß-carotene (ßC). This study reveals molecular interactions governing the formation, stabilization, and ßC uptake of OSßG micelles (OSßG-Ms) by means such as water contact angle, 1H nuclear magnetic resonance, dynamic light scattering, and confocal laser scanning microscopy. The results indicated that the micellization of OSßG molecules is triggered by hydrophobic interactions between octenylsuccinate (OSA) moieties, while OSßG-Ms are stabilized via both hydrophobic interactions and hydrogen bonds. For their uptake of ßC, ßC molecules are first adsorbed onto OSßG-Ms by interacting with OSA moieties scattered on micelle surface. By further interacting with OSA moieties located in micelle shell, ßC molecules travel across the shell and finally are trapped in the hydrophobic core. In simulated gastrointestinal fluids, ßC is controlled released from OSßG-Ms as an integrated consequence of its diffusion as well as the swelling and erosion of OSßG-Ms. As a result, this study first uncovered the mechanism underlying the uptake of ßC by OSßG-Ms, which will certainly facilitate the effective loading of hydrophobic ingredients by OSßG-Ms.


Assuntos
Avena/química , Preparações de Ação Retardada/química , Extratos Vegetais/química , Succinatos/química , beta Caroteno/química , beta-Glucanas/química , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Micelas , Estrutura Molecular
10.
Chem Commun (Camb) ; 55(44): 6173-6176, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31045185

RESUMO

A COOH-terminated nitrogen-doped carbon aerogel exhibited 100% selectivity to two-electron oxygen reduction, exceeding reported carbonaceous and noble metal catalysts. The optimal electrode with the synergistic effect of C-N/C-COOH resulted in a minimum ηO2/H2O2 and gave an evolution rate of 60 mg L-1 g-1 h-1 for H2O2 with satisfactory mechanical and electrochemical stability for practical applications.

11.
Ultrason Sonochem ; 56: 240-253, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101259

RESUMO

In considering the adverse nutritional and flavor consequences of thermal pasteurization on fruit juices, freshly squeezed and unpasteurized fruit juices, commonly called raw juices, are of increasing demand as they are served in bars, restaurants and at home. Apparently, due to lack of controlled processing regime as did in a juice factory, the raw juice often undergoes a rapid phase separation and is at the risk of microbial unsafety. To this end, an attempt of cold ultrasound treatment (CUT, 87.52 W/cm2, 10 °C) was implemented to a raw tomato juice up to 30 min. Appreciatively, the physical stability, nutritional value and microbial safety substantially improved. On a CUT time scale, cloud stability and total phenolic content continuously increased; the total plate count was adversely altered; the rheological parameters (viscosity, thixotropy and shear-thinning tendency) and total carotenoids obtained shared a parabolic changing pattern but peaked at 15 min and 10 min, respectively. Finally, the ascorbic acid sharply increased at an earlier stage (5 min), and then remained stable throughout the whole process. Notably, the occurrences of these improvements are of spatial-temporal nature and resulted from different cavitation induced stress fields. At the initial stage, CUT chiefly worked via the mechanical field with the particles in pulp phase, making them smaller and releasing the soluble materials into serum phase. When the particles larger than approximately of 160 µm were completely disintegrated, the CUT entered its second stage and mainly functioned in the serum phase via both mechanical and chemical fields. As a result, the serum pectin and carotenoids were depolymerized and degraded, respectively. The present results are valuable in uncovering the mechanism and kinetics underlying the ultrasound treatment of fruit juices and the present CUT is highly recommended due to its high maneuverability and excellent performance.


Assuntos
Temperatura Baixa , Qualidade dos Alimentos , Inocuidade dos Alimentos , Sucos de Frutas e Vegetais/análise , Lycopersicon esculentum/química , Sonicação/métodos , Paladar , Antioxidantes/análise , Ácido Ascórbico/análise , Carotenoides/análise , Sucos de Frutas e Vegetais/microbiologia , Fenóis/análise , Reologia , Análise Espaço-Temporal
12.
Nanoscale ; 11(25): 11992-12014, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31140537

RESUMO

Rapid global industrialization and explosive population growth have resulted in an increase in the discharge of harmful and toxic compounds. These toxic inorganic gases, volatile organic compounds, heavy metals, personal care products, endocrine-disrupting chemicals, dyes, and pharmaceuticals are destroying the balance in the Earth and increasing environmental toxicity at an alarming rate. Thus, their detection, adsorption and removal are of great significance. Various carbon nanomaterials including carbon nanotubes, graphene, mesoporous carbon, carbon dots, and boron-doped diamond have been extensively utilized and further proven to be ideal candidates for resolving environmental problems, emerging as adsorbents, electrochemical sensors and electrodes. Herein, we review the recent advances, progress and achievements in the design and properties of carbon nanomaterials and their applications for the electrochemical detection and removal of environmental pollutants.

13.
Anal Chem ; 91(12): 7639-7647, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31144808

RESUMO

Steroid estrogens, including 17ß-estradiol (TE2), estrone (TE1), and ethinyl estradiol (TEE2), which are the strongest endocrine disruptors and coexist in the environment, seriously harm the health of organisms; thus, the monitoring of total steroid estrogens (TEs) has attracted growing attention. Herein, a method based on surface-enhanced Raman spectroscopy (SERS) group-targeting detection is established to detect TEs in natural water for the first time. The TEs response detection range and detection limit were 0.01-50 nM and 5 pM, respectively. An anti-interference ability was observed: even if coexisting interfering species were present in the system at 100-fold the concentration of estrogens, the detection error of the method was less than 0.276. In addition, the association constants between the aptamers and TE1, TE2, and TEE2 were similar, and therefore, the recognition of TE1, TE2, and TEE2 by the aptamers was consistent. Furthermore, the interaction sites A44, T72, and G69 between the aptamers and TE1, TE2, and TEE2 were investigated by molecular docking. On this basis, the estrogens in environmental water samples, including animal farm wastewater, maternity hospital wastewater, surface water from near an animal farm, and surface water from near a maternity hospital, were successfully determined.

14.
Food Funct ; 10(6): 3044-3056, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31066412

RESUMO

As a group of non-coding RNA molecules, microRNAs have recently become more well-known due to their pivotal role in gene regulation. A large number of endogenous microRNAs naturally occur in the human body, and some of them act as regulatory targets of diet and its components. The wide presence of microRNAs in various food materials has inspired food scientists and nutritionists to explore their nutritive and bioactive significance. This article comprehensively reports updated insights into the accessibility, stability, absorbability, and bioactivity of dietary microRNAs by combining the current knowledge into figures and tables for reader's convenience. As one frontier in food science and nutrition, the research platform on dietary microRNAs is imperfect and even defective as indicated by the inconsistent and even contradictory results concluded by different investigations. The pros and cons as well as the limitations of current investigations have been critically discussed with attention chiefly paid to experimental designs and protocols. Moreover, future research directions have been recommended. Thus, this paper may not only provide a quick glance at the state-of-the-art of dietary microRNAs but also guide further research to clarify the present controversies and make the results more credible and persuasive.

15.
Int J Mol Sci ; 20(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010109

RESUMO

Whole-genome duplications (WGDs) are widespread in plants and frequently coincide with global climatic change events, such as the Cretaceous-Tertiary (KT) extinction event approximately 65 million years ago (mya). Ferns have larger genomes and higher chromosome numbers than seed plants, which likely resulted from multiple rounds of polyploidy. Here, we use diploid and triploid material from a model fern species, Ceratopteris thalictroides, for the detection of WGDs. High-quality RNA-seq data was used to infer the number of synonymous substitutions per synonymous site (Ks) between paralogs; Ks age distribution and absolute dating approach were used to determine the age of WGD events. Evidence of an ancient WGD event with a Ks peak value of approximately 1.2 was obtained for both samples; however, the Ks frequency distributions varied significantly. Importantly, we dated the WGD event at 51-53 mya, which coincides with the Paleocene-Eocene Thermal Maximum (PETM), when the Earth became warmer and wetter than any other period during the Cenozoic. Duplicate genes were preferentially retained for specific functions, such as environment response, further support that the duplicates may have promoted quick adaption to environmental changes and potentially resulted in evolutionary success, especially for pantropical species, such as C. thalictroides, which exhibits higher temperature tolerance.


Assuntos
Adaptação Fisiológica/genética , Gleiquênias/genética , Duplicação Gênica , Genes Duplicados , Genoma de Planta , Cromossomos de Plantas/genética , Diploide , Genes de Plantas , Proteínas de Domínio MADS/genética , Modelos Genéticos , Família Multigênica , Filogenia , Poliploidia
16.
Anticancer Res ; 39(4): 1849-1857, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952725

RESUMO

BACKGROUND/AIM: Melanoma-associated antigen A12 (MAGEA12) has recently been reported as a repressor of tumor-suppressor genes. This study aimed to investigate the implications of MAGEA12 expression in the pathogenesis of cutaneous squamous cell carcinoma (cSCC). MATERIALS AND METHODS: MAGEA12 and p21 expression were investigated in 15 samples of normal skin and 111 of cSCC tissues by immunohistochemistry. The biological functions of MAGEA12 in cSCC were also investigated both in vitro and in vivo. RESULTS: Expression of both MAGEA12 and p21 was significantly increased in cSCC. MAGEA12 expression showed a positive correlation, while p21 expression showed negative correlation with the recurrence-free survival of patients with cSCC. In addition, MAGEA12 knockdown significantly attenuated proliferative, migratory, invasive, and tumorigenic activities of cSCC cells and was negatively correlated with p21 expression both in vitro and in vivo. CONCLUSION: MAGEA12-mediated down-regulation of p21 may be involved in cSCC pathogenesis and MAGEA12 may serve as a molecular biomarker in cSCC.


Assuntos
Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Intervalo Livre de Progressão , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Adulto Jovem
17.
Small ; : e1900153, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30848873

RESUMO

Boron-doped diamond-based electrochemical advanced oxidation processes (BDD-EAOPs) have attracted much attention. However, few systematic studies concerning the radical mechanism in BDD-EAOPs have been published. In situ electron paramagnetic resonance spectrometry is used to confirm that SO4 •- is directly electrogenerated from SO4 2- . Then, excess SO4 •- dimerizes to form S2 O8 2- and accumulates in the BDD-EAOP system. But no S2 O8 2- accumulates at pH = 10 owing to the rapid transformation of SO4 •- and S2 O8 2- . Above the overpotential of water oxidation, • OH is electrogenerated and cooperated with SO4 •- . In the power-off phase, the accumulated S2 O8 2- can be reactivated to SO4 •- via specific degradation intermediates to achieve sustainable degradation. Di-n-butyl phthalate (DnBP), a typical endocrine disruptor, is selected as a model contaminant. Surprisingly, 99.8% of DnBP (initial concentration of 1 mg L-1 ) is removed, using an intermittent power supply strategy with a periodic 10 min power-on phase at a duty ratio of 1:2, reducing the electrical energy consumption (1.8 kWh m-3 ) by more than 30% compared with continuous power supply consumption. These radical electrogeneration transformation mechanisms reveal an important new strategy for sustainable oxidation, especially for in situ water restoration, and are expected to provide a theoretical basis for BDD applications.

18.
Epilepsy Behav ; 94: 47-51, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30884407

RESUMO

PURPOSE AND METHODS: Persons with epilepsy (PWE) remain completely and permanently prohibited from driving in China currently. Previous studies have shown that a considerable proportion of PWE with uncontrolled seizures in China continue to drive motor vehicles. Discrepancy between Chinese policy and driving practices for PWE is potentially concerning. We conducted a preliminary online electronic questionnaire (e-questionnaire) survey among neurologists in China aiming to explore neurologists' attitudes toward the issue of driving among PWE. RESULTS: A total of 358 neurologists completed the e-questionnaire with a response rate of 75.8%. 50.3% of neurologists stated that they knew the driving restriction law in China. With respect to reporting of cases to relevant driving authorities, 82.4% of neurologists never directly report PWE, and 90.8% consider that it is PWE's responsibility to report themselves. 87.4% of physicians surveyed indicated that the lack of clearly-articulated guidelines is a major impediment to their routine discussions of driving fitness for PWE. Subgroup analysis indicated that 76.2% of epileptologists were of the opinion that persons with well-controlled epilepsy should be allowed to drive versus 56.2% of general neurologists (P < 0.05). CONCLUSION: Currently, neurologists in China have a low awareness of the legal driving restriction for PWE and have highly varying practices with respect to counseling PWE about driving. According to our preliminary results, a clearly-articulated published national document for medical fitness for driving in China is necessary in order to standardize physicians' practices.

19.
Carbohydr Polym ; 213: 79-88, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879692

RESUMO

The effects of spontaneous fermentation on the molecular and physicochemical characteristics of sweet potato starch stored in tank during twelve months were investigated. From starch slurry collected during spontaneous fermentation, eight isolates showed amylolytic activity, which included two Acetobacter strains, five Bacillus strains and one Gluconacetobacter strain. By spontaneous fermentation, the amylose content and the average molecular weight of starch were significantly decreased. Besides, the native and fermented starches showed different amylopectin chain-length distribution patterns. Among them, no significant differences in granular morphology, granule size distribution, and crystalline structure. However, the thermal and pasting properties as well as the hardness of the starch gel differed significantly. Pearson's correlation analysis showed that the physicochemical properties was mainly influenced by the changes in the amylose content, amylopectin chain-length distribution as well as the average molecular weight of starch. These findings demonstrated the feasibility of spontaneous fermentation as a tool for modifying starches.


Assuntos
Ipomoea batatas/metabolismo , Amido/metabolismo , Química Física , Fermentação , Ipomoea batatas/química , Peso Molecular , Tamanho da Partícula , Amido/química , Propriedades de Superfície
20.
Int J Biol Macromol ; 131: 1057-1066, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30885733

RESUMO

Chitosan (CH) and pectin (PE) are considered as promising biomaterials in developing eco-friendly films due to their film-forming, biodegradable, and non-toxic characteristics, the films from pure CH or PE have obvious defects such as poor barrier and mechanical properties. In this study, the blend films of CH and PE at varying mass ratios were characterized. Structurally, numerous small pores evenly distributed in PE film while big caves unevenly scattered in CH film. CH film is semicrystalline but PE and blend films are totally amorphous, the two individual films presented comparable values in water content and solubility to blend films. The CH film showed lower water vapor permeability and surface wettability and these parameters of the blend films decreased with CH level, the blend films exhibited high transparence as PE film did, which is much higher than that of CH film. Mechanically, the PE film presented higher values in stretchability and tensile strength than CH film. Moreover, in a different blending ratios, synergistic effects were found with several characters of the CH/PE blend film, especially in transparence and mechanical properties. These synergistic effects were ascribed to the intermolecular electrostatic interactions between CH and PE.


Assuntos
Materiais Biocompatíveis/química , Fenômenos Químicos , Quitosana/química , Malus/química , Pectinas/química , Permeabilidade , Solubilidade , Análise Espectral , Vapor , Resistência à Tração , Água/química
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