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1.
Food Chem ; 305: 125382, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525590

RESUMO

During the mashing process for brewing beer, incomplete degradation of arabinoxylan in barley malt may cause an intense filterability problem. The present study cloned a putative arabinofuranosidase (AnAbf), one of the debranching enzymes, from Aspergillus niger, to explore its application for improving filterability. Recombinant AnAbf (rAnAbf) showed activity towards both synthetic and natural substrates, such as 4-nitrophenyl α-l-arabinofuranoside (pNPαAraf) and malt water extractable arabinoxylan (WEAX), which was maximized at a temperature of 50 °C and pH of 5.5. Metal ions did not increase the activity of rAnAbf, indicating a difference in its C-terminal domain from that of type II GH43 family members. rAnAbf also exhibited a synergistic effect with ß-xylanase against WEAX. The filtration rate of the wort increased by 12.8% after supplementing with rAnAbf during the initial stage of mashing. A slight decrease in viscosity and an unexpected increase in turbidity were observed.

2.
J Hazard Mater ; 382: 121025, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31446351

RESUMO

The fate of antibiotic resistance genes (ARGs) in reclaimed water reuse system with integrated membrane process (IMR) was firstly investigated. Results indicated that ARGs, class 1 integrons (intI1) and 16S rRNA gene could be reduced efficiently in the IMR system. The absolute abundance of all detected ARGs in the reuse water after reverse osmosis (RO) filtration of the IMR system was 4.03 × 104 copies/mL, which was about 2-3 orders of magnitude lower than that in the raw influent of the wastewater treatment plants (WWTPs). Maximum removal efficiency of the detected genes was up to 3.8 log removal values. Daily flux of the summation of all selected ARGs in the IMR system decreased sharply to (1.02 ±â€¯1.37) ×1014 copies/day, which was 1-3 orders of magnitude lower than that in the activated sludge system (CAS) system. The strong clustering based on ordination analysis separated the reuse water from other water samples in the WWTPs. Network analysis revealed the existence of potential multi-antibiotic resistant bacteria. The potential multi-antibiotic resistant bacteria, including Clostridium and Defluviicoccus, could be removed effectively by microfiltration and RO filtration. These findings suggested that the IMR system was efficient to remove ARGs and potential multi-antibiotic resistant bacteria in the wastewater reclamation system.

3.
J Hazard Mater ; 382: 121040, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470294

RESUMO

Dyes and heavy-metal ions are common pollutants in printing and dyeing wastewater, and are thus attracting considerable attention. Herein, an eco-friendly straw-based adsorbent, WS-CA-AM, was prepared by grafting with acrylamide (AM) and citric acid (CA) groups to remove representative dyes and heavy metals from aqueous solution. The adsorption capacities of WS-CA-AM for methyl orange (MO) and methylene blue (MB) were 3053.48 and 120.84 mg/g, which were 54 and 3 times those of unmodified straw, respectively. Moreover, the adsorption capacities for MB, MO, Cr2O72- and Cu2+ in the mixed system increased by 210%, 133%, 196% and 151%, respectively, compared with those in the single system. The significant increase in adsorption capacity can be attributed to the collaborative effect through electrostatic attraction. The functional groups and adsorbed pollutants all served as adsorption sites for pollutants. These results indicate that WS-CA-AM is a potential applicant for the removal of dyes and heavy-metal ions from mixed aqueous solution.

4.
Ecotoxicol Environ Saf ; 187: 109852, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31670243

RESUMO

Microplastics have become emerging pollutants and served as potential vectors for harmful bacteria, while rare information on the emergency and propagation of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) on the surface of microplastics is available. This study investigated the enrichment of ARB, especially multi-antibiotic resistant bacteria (MARB), on the surface of microplastics in mariculture system. Polyethylene terephthalate accounted for the highest proportion (75%) in the collected microplastics. The counts of cultivable ARB in microplastic samples were 6.40 × 106-2.48 × 108 cfu/g, which were 100-5000 times higher than those in water samples. The ratios of cultivable ARB to total cultivable bacteria from microplastic samples were higher than those from water samples. High-throughput sequencing showed that the diversity and abundance of cultivable ARB in the microplastic samples was high with the predominant bacterial genera of Vibrio, Muricauda and Ruegeria. Total 160 MARB isolates were obtained and most of isolates were obtained from the microplastic samples. MARB isolates resisting or intermediating to four and three antibiotics accounted for much higher proportions in the microplastic samples, and the higher percentage of antibiotic resistance was to penicillin, sulfafurazole, erythromycin and tetracycline. The dominant multiple antibiotic resistance profile was TET-SFX-ERY-PEN, which accounted for 25.4% in microplastic samples and 23.9% in water samples. In typical MARB isolates, the positive detection rate of ARGs was up to 80.0% in microplastic samples while that was 65.3% in water samples. Five types of class 1 integrons (intI1) associated gene cassette arrays and seven types of gene cassettes were detected in microplastic samples, which were more than those in water samples. These results revealed that microplastics were hazardous pollutants for the enrichment of ARB, especially superbugs, and the spread of antibiotic resistance.

5.
Small ; : e1905731, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31668013

RESUMO

Memristors are emerging as a rising star of new computing and information storage techniques. However, the practical applications are severely challenged by their instability toward harsh conditions, including high moisture, high temperatures, fire, ionizing irradiation, and mechanical bending. In this work, for the first time, lead-free double perovskite Cs2 AgBiBr6 is utilized for environmentally robust memristors, enabling highly efficient information storage. The memory performance of the typical indium-tin-oxide/Cs2 AgBiBr6 /Au sandwich-like memristors is retained after 1000 switching cycles, 105 s of reading, and 104 times of mechanical bending, comparable to other halide perovskite memristors. Most importantly, the memristive behavior remains robust in harsh environments, including humidity up to 80%, temperatures as high as 453 K, an alcohol burner flame for 10 s, and 60 Co γ-ray irradiation for a dosage of 5 × 105 rad (SI), which is not achieved by any other memristors and commercial flash memory techniques. The realization of an environmentally robust memristor from Cs2 AgBiBr6 with a high memory performance will inspire further development of robust electronics using lead-free double perovskites.

6.
J Clin Pharm Ther ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31579951

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Hexavalent (VI) chromium is a powerful oxidant that can produce cellular oxidative stress and multi-organ system dysfunction. The role of antioxidants such as N-acetylcysteine (NAC) and ascorbic acid in alleviating organ damage in humans remains unclear. CASE DESCRIPTION: We present a 47-year-old male who ingested 30 mL of plating solution and developed hepatic injury. He was treated with NAC and ascorbic acid with improvement in hepatic function. However, his clinical conditions and jaundice worsened again after discontinuing these therapies. WHAT IS NEW AND CONCLUSION: Our findings suggest a potential role for antioxidant therapy for acute hexavalent chromium poisoning.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31581079

RESUMO

The point spread function (PSF) is often analyzed to determine the image quality of an ultrasound system. The formation of PSF is determined by practical factors such as transducer aperture, element directivity, apodization, pitch, imaging position and steering angle. Conventional numerical simulations provide an iterative approach to examine those factors' effects but cannot explain the inherent mechanism of PSF formation. This paper presents a theoretical approximation of PSF formation for plane wave imaging throughout the Fourier-based reconstruction process. Aforementioned factors are incorporated in the theory. The proposed theory is used to analyze the effects of those factors and presents a high degree of consistency with numerical simulations and experiments.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(5): 1585-1591, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31607316

RESUMO

OBJECTIVE: To perform genetic analysis, prenatal diagnosis and preimplantation genetic diagnosis (PGD) in a family with a rare deletional ß- thalassemia. METHODS: Hematological parameters of the peripheral blood collected from all the family members were analyzed by whole blood cell analysis and capillary zone electrophoresis (CZE). Polymerase chain reaction-reverse dot blot (PCR-RDB) was used to identify 17 common ß- thalassemia gene mutations, the multiplex ligation-dependent probe amplification (MLPA) and gap-polymerase chain reaction (gap-PCR) were used to identify ß- globin gene cluster deletions. Chorionic villus sample or umbilical cord blood was obtained for prenatal diagnosis. Oligo-cells from blastocyst biopsy were collected for preimplantation genetic diagnosis by whole genome amplification and next generation sequencing. RESULTS: The proband was a carrier of Taiwanese deletion ß- thalassemia, two fetuses were both thalassemia majors. The PGD results showed that 6 of 11 tested embryos could be choose for transplantation. CONCLUSION: The Taiwanese deletion is a rare type deletion of ß- globin gene cluster, and it can lead to thalassemia intermedia or thalassemia major when compounded with other ß- globin gene mutation. PGD is another choice for thalassemia couples.

9.
Chemistry ; 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31654431

RESUMO

The precious metal catalyst (such Au, Pd, Rh, Ag, Ru, Pt and Pd) which was supported on transition metal oxide (for example, Al 2 O 3 , Fe 2 O 3 , CeO 2 , ZrO 2 , Co 3 O 4 , MnO 2 , TiO 2 and NiO) can effectively oxidize VOCs. In this study, porous platinum-supported zirconia materials were prepared by a "surface-casting" method. The synthesized catalyst presents an ordered nanotube structure and exhibits excellent performance toward the catalytic oxidation of formaldehyde. Herein, a facile method, utilizing a boiling water bath, was used to fabricate graphene aerogels (GA), and a macroscopic 3D Pt/ZrO 2 -GA was modified by introducing an adjustable MOF coating via a surface step-by-step method. The unblocked mesoporous structure of the graphene aerogel facilitates the ingress and egress of reactants and product molecules. The selected MOF-5 composite demonstrates excellent performance for HCHO adsorption. Additionally, the 7wt.% Pt/ZrO 2 -GA-MOF-5 catalyst achieved ~90% conversion when subjected to a reaction temperature of 70°C (T 90% =70°C). The Pt/ZrO 2 -GA-MOF-5 composite induces a catalytic cycle, that is, increasing the reaction rate by simultaneously adsorbing and oxidizing HCHO. This work provides a simple way to increase reactant concentration on the catalyst to increase the reaction rate.

10.
Nucleic Acids Res ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647098

RESUMO

Alternative splicing is emerging as an oncogenic mechanism. In prostate cancer, generation of constitutively active forms of androgen receptor (AR) variants including AR-V7 plays an important role in progression of castration-resistant prostate cancer (CRPC). AR-V7 is generated by alternative splicing that results in inclusion of cryptic exon CE3 and translation of truncated AR protein that lacks the ligand binding domain. Whether AR-V7 can be a driver for CRPC remains controversial as the oncogenic mechanism of AR-V7 activation remains elusive. Here, we found that KDM4B promotes AR-V7 and identified a novel regulatory mechanism. KDM4B is phosphorylated by protein kinase A under conditions that promote castration-resistance, eliciting its binding to the splicing factor SF3B3. KDM4B binds RNA specifically near the 5'-CE3, upregulates the chromatin accessibility, and couples the spliceosome to the chromatin. Our data suggest that KDM4B can function as a signal responsive trans-acting splicing factor and scaffold that recruits and stabilizes the spliceosome near the alternative exon, thus promoting its inclusion. Genome-wide profiling of KDM4B-regulated genes also identified additional alternative splicing events implicated in tumorigenesis. Our study defines KDM4B-regulated alternative splicing as a pivotal mechanism for generating AR-V7 and a contributing factor for CRPC, providing insight for mechanistic targeting of CRPC.

11.
Chem Asian J ; 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31617314

RESUMO

A triphenylamine derivative decorated with an azobenzene group (TDA) was synthesized via a SuFEx click reaction and its polymer, poly(triphenylamine) (PTDA), was polymerized through a redox polymerization. More interestingly, its polymeric metal complex, PTDA-Fe, can be simply obtained via one-pot reaction between TDA and FeCl3 owing to TDA showing a strong affinity to the Fe(III) ion.  The sandwich memory device based on PTDA nanofilms as active layers exhibited a binary memory performance.  However, the memory device based on its polymeric metal complex exhibited a unique ternary memory behavior. The different memory performances should come from the different conductive mechanism. The mechanism of such ternary memory devices is illustrated based on both the theoretical calculation and experiments. Our work provides new insights into the preparation of novel materials for multilevel memory devices.

12.
J Hazard Mater ; : 121271, 2019 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-31611021

RESUMO

Land spreading of sewage sludge is a major source of environmental microplastics (MPs) contamination. However, conventional sludge treatments are inefficient at removing sludge-based MPs. Herein, hyperthermophilic composting (hTC) technology is proposed and demonstrated in full-scale (200 t) for in situ biodegradation of sludge-based MPs. After 45 days of hTC treatment, 43.7% of the MPs was removed from the sewage sludge, which is the highest value ever reported for MPs biodegradation. The underlying mechanisms of MPs removal were investigated in lab-scale polystyrene-microplastics (PS-MPs) biodegradation experiments. The hTC inoculum degraded 7.3% of the PS-MPs at 70 °C in 56 days, which was about 6.6 times higher than that of the conventional thermophilic composting (cTC) inoculum at 40 °C. Analyses of the molecular weight and physicochemical properties of the PS-MPs residuals indicated that hyperthermophilic bacteria in hTC accelerated PS-MPs biodegradation through excellent bio-oxidation performance. High-throughput sequencing suggested that Thermus, Bacillus, and Geobacillus were the dominant bacteria responsible for the highly efficient biodegradation during hTC. These results reveal the critical role of hyperthermophilic bacteria in MPs biodegradation during hTC, highlighting a promising strategy for sludge-based MPs removal from the real environment.

13.
Mol Cancer ; 18(1): 146, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31647023

RESUMO

Programmed death ligand 1 (PD-L1), a type I transmembrane protein, binds to its receptor PD-1 to suppress the activation of T cells, thereby maintaining immunological homeostasis. In contrast, tumor cells highly express PD-L1, which binds to receptor PD-1 expressed on activated T cells, leading to immune escape. Anti-PD-1/PD-L1 immune checkpoint therapy blocks the binding of PD-1/PD-L1 to reinvigorate the exhausted T cells, thereby inhibiting tumor growth. Exosomes are biologically active lipid-bilayer nanovesicles secreted by various cell types that mediate intercellular signal communication. Numerous studies have shown that tumor cells are able to promote tumor epithelial-mesenchymal transition, angiogenesis, and immune escape by releasing exosomes. Recent studies imply that tumor-derived exosomes could carry PD-L1 in the same membrane topology as the cell surface, thereby resisting immune checkpoint therapy. In this review, we mainly discuss the role of exosomes in the regulation of tumor progression and the potential resistance mechanism to immunotherapy via exosomal PD-L1. In addition, we propose that exosomal PD-L1 may have the potential to be a target to overcome resistance to anti-PD-1/PD-L1 antibody therapy.

14.
Food Chem ; 308: 125665, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31655473

RESUMO

The effects of different dissolved oxygen concentrations (DOC) on the browning degree, amino acids, total phenols, reducing sugars, polyphenoloxidase (PPO), peroxidase (POD), phenylalanine ammonia-lyase (PAL) of pear wine, and the relationship between various quality indicators and browning degree were investigated. Dynamic model fitting analysis of the changes of physiochemical indicators of pear wine in the storage process were performed. The importance of the physiochemical indicators effect on the browning of pear wine during the storage process was analyzed by OPLS (orthogonal partial least squares discriminant analysis), and the effect of dissolved oxygen on the browning of pear wine was systematically revealed. The results showed that dissolved oxygen, total phenols and amino acids had the greatest influence on the browning degree of pear wine. It provided a theoretical basis for revealing the browning mechanism and inhibiting the browning of pear wine.

15.
BMC Cancer ; 19(1): 1020, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664937

RESUMO

BACKGROUND: Accumulating evidence suggests that Gamma-glutamyltransferase (GGT) may be involved in cancer occurrence and progression. However, the prognostic role of serum GGT in pancreatic cancer (PC) survival lacks adequate evaluation. In this study, we aimed to analyze the association between serum GGT measured at diagnosis and overall survival (OS) in patients with metastatic PC. METHODS: We identified 320 patients with histopathologically confirmed metastatic pancreatic ductal adenocarcinoma (PDAC) diagnosed during 2015 and 2016 at a specialized cancer hospital in southwestern China. Univariate and multivariate Cox proportional-hazards models were used to determine associations between serum GGT and OS in metastatic PDAC. RESULTS: Controlled for possible confounding factors, serum GGT was significantly associated with OS: serum GGT > 48 U/L yielded a hazard ratio of 1.53 (95% CI: 1.19-1.97) for mortality risk. A significant dose-response association between serum GGT and OS was also observed. Subgroup analysis showed a possible interaction between GGT and blood glucose level. CONCLUSION: Serum GGT could be a potential indicator of survival in metastatic PDAC patients. Underlying mechanisms for this association should be investigated.

16.
Dev Comp Immunol ; 103: 103513, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585194

RESUMO

Adrenergic receptors (ARs) are members of the G-protein-coupled receptor superfamily that can be categorized into αARs and ßARs. The specific function of ARs in teleost monocytes/macrophages (MO/MФ) remains unknown. We determined the cDNA sequence of ARs from ayu (Plecoglossus altivelis; PaαAR and PaßAR). Sequence comparisons showed that PaαAR was most closely related to the αAR of the Japanese flounder and Nile tilapia, while PaßAR was most closely related to the ßAR of Atlantic salmon. The AR transcripts were mainly expressed in the spleen, and their expression was altered in various tissues upon infection with Vibrio anguillarum. PaαAR and PaßAR proteins were upregulated in MO/MФ after infection, and PaßAR knockdown resulted in a pro-inflammatory status in ayu MO/MФ upon V. anguillarum infection and lowered the phagocytic activity of MO/MФ. Our results indicate that PaßAR plays the role of an anti-inflammatory mediator in the immune response of ayu against bacterial infection.

17.
J Hazard Mater ; 384: 121267, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31574385

RESUMO

A novel hybrid nanoreactor with spatially separated co-catalysts (SH-CD-Au@CdS@MnOx) was successfully synthesised to remove bisphenol-A (BPA) from water by visible light. The photooxidation intermediates, degradation pathway of BPA and the enhancement mechanism were investigated in particular. Gold (Au) nanoparticles modified with SH-ß-cyclodextrin and MnOx nanoparticles were selectively decorated on the interior and exterior surface of hollow CdS nanoreactors, respectively. The directed migration of photogenerated electrons and holes induced by spatially separated co-catalysts lead to high utilization of light, and SH-ß-cyclodextrin modification makes catalytic active sites more accessible for oxidation intermediates. Compared with pristine CdS, the hybrid nanoreactor increased the BPA photooxidation reaction rate and the TOC removal efficiency by 5.6-fold and 3.6-fold, respectively. Moreover, the toxic intermediates, such as phenol, were further degraded by visible light. Molecular orbital calculation predicted that the sites on BPA molecule values of (FED2HOMO + FED2LUMO) can be easier attacked by the radical, whereas atoms with higher values of 2FED2HOMO can easily be extracted into electrons. Thus, SH-CD-Au@CdS@MnOx can provide a new strategy for the high-efficiency photodegradation of endocrine disrupter compounds in advanced water treatments.

18.
Chem Commun (Camb) ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31664282

RESUMO

Efficient cathode-ray scintillating metal-organic frameworks are constructed from a π-conjugated luminescent motif and light Ca(ii) ions. The luminescence self-quenching pathway has been effectively hindered through coordination. In situ vacuum ultraviolet fluorescent spectra have shown the excitons recombining in the scintillation process for the first time.

19.
Small ; : e1903188, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31650707

RESUMO

Conjugated coordination polymers have become an emerging category of redox-active materials. Although recent studies heavily focus on the tailoring of metal centers in the complexes to achieve stable electrochemical performance, the effect on different substitutions of the bridging bonds has rarely been studied. An innovative tailoring strategy is presented toward the enhancement of the capacity storage and the stability of metal-organic conjugated coordination polymers. Two nanostructured d-π conjugated compounds, Ni[C6 H2 (NH)4 ]n (Ni-NH) and Ni[C6 H2 (NH)2 S2 ]n (Ni-S), are evaluated and demonstrated to exhibit hybrid electrochemical processes. In particular, Ni-S delivers a high reversible capacity of 1164 mAh g-1 , an ultralong stability up to 1500 cycles, and a fully recharge ability in 67 s. This tailoring strategy provides a guideline to design future effective conjugated coordination-polymer-based electrodes.

20.
Org Lett ; 21(19): 8018-8021, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31553198

RESUMO

In the presence of a carboxylic acid directing group, Rh-catalyzed regioselective directed dialkylation of B(4,5)-H bonds in o-carboranes and oxidative coupling with allylic alcohols is reported. This strategy constructs a series of 4,5-dialkylated o-carboranes in good yields with excellent regioselectivity. A possible catalytic cycle is proposed that involves a tandem sequence of Rh-catalyzed cage B-H activation, alkene insertion, selective ß-H elimination, enol isomerization, and decarboxylation.

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