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1.
J Sex Med ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31668731

RESUMO

INTRODUCTION: Acellular dermal matrix (ADM) is a common filler used widely in clinical practice to increase penile girth for cosmetic reasons, but there are few studies on its complications. AIM: The aim of this study was to investigate and analyze the complications of penile girth enhancement (PGE) with ADM. METHODS: The medical records of 78 patients who underwent PGE with ADM between June 2016 and January 2019 were retrospectively reviewed. MAIN OUTCOME MEASURE: Related complications and their subsequent management were summarized and analyzed. RESULTS: 78 patients (mean age 31.14 years [21-66 years]) received PGE with ADM. At the 3-month follow-up, the penile circumference was increased by 1.1 (0.5-2.1) cm on average. There were 47 patients with erectile discomfort, 12 with delayed healing, 10 with unobvious augmentation effect, 8 with wound hematoma, 7 with prepuce edema, 4 with wound infection, and 3 patients with skin necrosis of the dorsal side. 7 patients eventually underwent ADM removal. CLINICAL IMPLICATIONS: These adverse complications indicate that ADM should be used with caution for PGE. STRENGTH & LIMITATIONS: This study adds important data, as there are few published reports on the complications of PGE with ADM. However, this study did not compare postoperative complications with ADM to those seen with other filler material. CONCLUSION: Even with standardized surgical methods and rigorous postoperative care, complications of PGE using ADM are severe, which indicates that it is not an ideal or safe method for PGE. Xu T, Zhang G, Bai W, et al. Complications and Management of Penile Girth Enhancement with Acellular Dermal Matrix. J Sex Med 2019;XX:XXX-XXX.

2.
Environ Int ; 134: 105230, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31704569

RESUMO

Aquatic ecosystems are monitored worldwide using a range of biological quality elements that are morphologically identified. The environmental DNA (eDNA)-based approach has unprecedented advantages (e.g., high throughput, high efficiency and low cost) for biodiversity surveys in both freshwater and marine ecosystems compared with traditional sampling and image recognition. The use of eDNA has been mostly limited to biodiversity estimation, how to apply the eDNA approach in assessing the ecological health status is largely unexplored. Here, using zooplankton as an example, we examined the application of eDNA monitoring for ecological status assessment in an aquatic ecosystem. The results showed that eDNA monitoring reflected the spatial and temporal variations in zooplankton structure. Both species composition and bio-interactions varied significantly between sampling seasons (dry, normal and wet). A total of 60 different zooplankton indices were calculated based on eDNA monitoring and most of these indices were highly correlated with the level of water pollution, which was indicated by the water quality index in one or all three seasons. Both qualitative and quantitative eDNA-based biological indices were correlated with water quality. The season-dependent eDNA zooplankton integrity index (IZI) reflected the ecological status, and this method improves the timeliness of bioassessment.

3.
Mol Plant ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31706032

RESUMO

Symbiotic microorganisms improve nutrient uptake by plants. To initiate mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, plants perceive Myc factors, including lipochitooligosaccharides (LCOs) and short-chain chitooligosaccharides (CO4/CO5), secreted by AM fungi. However, the molecular mechanism of Myc factors perception remains elusive. Here, we identified a heteromer of LysM receptor-like kinases, OsMYR1/OsLYK2 and OsCERK1, that mediates perception of AM fungi in rice. CO4 directly binds to OsMYR1, promoting the dimerization and phosphorylation of this receptor complex. Compared to control plants, Osmyr1 and Oscerk1 mutant rice plants are less sensitive to Myc factors and show decreased AM colonization. We engineered transgenic rice by expressing chimeric receptors that respectively replaced the ectodomains of OsMYR1 and OsCERK1 with those from the homologous Nod factor receptors MtNFP and MtLYK3 of Medicago truncatula. Transgenic plants displayed increased calcium oscillations in response to Nod factors compared to control rice. Our findings reveal a mechanism for mycorrhizal symbiotic signal perception in rice, and the ectopic expression of chimeric Nod/Myc receptors achieves a potentially important step towards generating cereals that host nitrogen-fixing bacteria.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31658507

RESUMO

BACKGROUND: Parasympathetic nerve hypersensitivity contributes to the severity of allergic rhinitis (AR), but the precise mechanism underlying neuroimmune regulation in patients with AR remains unclear. This study investigated the effect of cholinergic nerve inhibition on AR CD4+ T-helper (Th)2-cell polarization and the underlying regulatory mechanism in vitro. METHODS: An in-vitro neuroimmune coculture model of D-U87 cells and CD4+ T cells was established. D-U87 cells with cholinergic neuron characteristics were used as cholinergic neuron models. CD4+ T cells were derived from peripheral blood monocytes from AR patients (n = 60) and control subjects (n = 40). Th1- and Th2-cell percentages were measured by flow cytometry. Proteins involved in related signaling pathways were analyzed by protein chip assay and Western blotting. RESULTS: The Th2-cell percentage among CD4+ T cells from AR patients was significantly increased after coculture with D-U87 cells and was decreased by ipratropium bromide (IB) treatment. In contrast, the Th1-cell percentage among control CD4+ T cells was significantly increased after coculture with D-U87 cells, but was unaltered by IB treatment. Furthermore, phosphorylated Akt (p-Akt) protein levels increased in CD4+ T cells from both controls and AR patients after coculture with D-U87 cells and decreased after IB treatment. However, higher p-Akt levels were observed in cells from AR patients than in cells from control subjects. Moreover, Akt inhibition decreased Th2-cell percentage in AR patients. CONCLUSION: In-vitro cholinergic nerve inhibition with IB decreased AR CD4+ T-cell polarization into Th2 cells partially through an Akt-dependent mechanism.

5.
J Agric Food Chem ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31630515

RESUMO

Biochanin A is a dietary isoflavone with multiple biological functions. Owing to a lack of comprehensive studies of biochanin A metabolism, this study was designed to further clarify the processes involved in biochanin A metabolism. In this study, ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) was utilized to characterize the metabolism of biochanin A in vivo and in vitro. As a result, 43 metabolites in rats, 22 metabolites in liver microsomes, and 18 metabolites in intestinal flora were elucidated, and 5 metabolites were identified by comparison with standards. Oxidation, demethylation, hydrogenation, internal hydrolysis, conjugation (e.g., glucuronidation, sulfonation, glucose conjugation, methylation, and acetylation), and their composite reactions were determined to be major processes involved in biochanin A biotransformation. The results contribute to a better understanding of the pharmacological mechanism of biochanin A and provide a basis for comprehension of the safety and toxicity of biochanin A.

6.
Phys Chem Chem Phys ; 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31657411

RESUMO

A series of MIL-101-SO3H/Nafion composite membranes was synthesized. They show an improved proton conductivity, due to the abundance of SO3H groups, which fosters proton conduction by binding the water molecules and enabling a larger number of conducting sites. Gas (including water vapor, hydrogen, and oxygen) permeability, crystallinity, and free volumes of the MIL-101-SO3H/Nafion composite membranes were investigated, as well as their correlation. By increasing the MIL-101-SO3H content, the gas permeability of the membranes significantly decreases, since the crystalline region is larger and the water-bearing MIL-101-SO3H particles are efficient barriers for the gas molecules. The gas permeation in the composite membranes is a very complex process and the results indicate no simple linear relation between the gas permeability and the free volume size (VFV), or between the gas permeability and the crystallinity. Moreover, it is very interesting to observe that the influence of VFV on the gas permeability is closely related to the size of the particular gas molecules: the larger the size of the gas molecules, the larger the free volume needed to achieve their rapid diffusion in the membrane. The results suggest the presence of a threshold value for VFV, which depends on the size of the gas molecules: when VFV is lower than this value, the gas molecules cannot easily jump through neighboring free volumes to a neighboring site, and, as a result, the permeability drops quickly.

7.
J Am Heart Assoc ; 8(20): e012338, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31576776

RESUMO

Background Heart failure (HF) is one of the most significant causes of morbidity and mortality for the cardiovascular risk population. We found previously that extracellular HSP70 (heat shock protein) is an important trigger in cardiac hypertrophy and fibrosis, which are associated with the development of heart dysfunction. However, the potential role of HSP70 in response to HF and whether it could be a target for the therapy of HF remain unknown. Methods and Results An HF mouse model was generated by a single IP injection of doxorubicin at a dose of 15 mg/kg. Ten days later, these mice were treated with an HSP70 neutralizing antibody for 5 times. We observed that doxorubicin treatment increased circulating HSP70 and expression of HSP70 in myocardium and promoted its extracellular release in the heart. Blocking extracellular HSP70 activity by its antibody significantly ameliorated doxorubicin-induced left ventricular dilation and dysfunction, which was accompanied by a significant inhibition of cardiac fibrosis. The cardioprotective effect of the anti-HSP70 antibody was largely attributed to its ability to promote the resolution of myocardial inflammation, as evidenced by its suppression of the toll-like receptor 2-associated signaling cascade and modulation of the intracellular distribution of the p50 and p65 subunits of nuclear factor-κB. Conclusions Extracellular HSP70 serves as a noninfectious inflammatory factor in the development of HF, and blocking extracellular HSP70 activity may provide potential therapeutic benefits for the treatment of HF.

8.
Environ Int ; 133(Pt B): 105214, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31665682

RESUMO

Understanding the extent and directionality of the impact of human activities on ecosystems is directly related to their management and protection. However, the lack of historical data limits our understanding of ecosystem changes with long-term exposure to human activities. Recently, lake sedimentary DNA (sedDNA) has become a powerful tool for revealing changes in ecosystems at the century and millennium scales. Here, we used sedDNA to reveal the dynamic of the microbial community (including bacteria and micro-eukaryotes) in Lake Chao over the past 150 years, and further explored the effects of long-term nutrient and heavy metal loads on these communities. Our data show that nutrient and heavy metal loads in Lake Chao have increased by ca. 2 to 4-fold since the 1960s. In response, the community structure, diversity, and ecological network of bacteria and micro-eukaryotes changed significantly during the 1960s, the 1980s and the 2010s. Importantly, community structure was more sensitive to human activities than diversity. We also found that the relative abundance of some taxa associated with nitrification and algal blooms (e.g., taxa in Nitrospira sp., Peridinales) has increased ca. 100-fold since the 1960s. Nutrient could better explain the variation in the bacterial community (ca. twice as much as heavy metal), while heavy metal explained micro-eukaryotes better (ca. 3 or 5-fold as much as nutrient). In particular, based on parsimonious models from distance-based linear model (distLM), we further identified that Pb is the key factor affecting the bacterial and micro-eukaryotes community in Lake Chao in addition to nutrient. Our study reveals the impacts of long-term human activities on lake ecosystems from multiple perspectives of nutrient and heavy metal loads, community structure, diversity and ecological network, these findings will contribute to the management and conservation of lakes in the future.

9.
Plant J ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31571281

RESUMO

Drought stress induces anthocyanin biosynthesis in many plant species. However, the underlying molecular mechanism remains unclear. Ethylene response factors (ERFs) play key roles in plant growth and various stress responses including affecting anthocyanin biosynthesis. Here, we characterized an ERF protein MdERF38 involved in drought stress-induced anthocyanin biosynthesis. Biochemical and molecular analyses showed that MdERF38 interacted with MdMYB1, a positive modulator of anthocyanin biosynthesis, and facilitated the binding of MdMYB1 to its target genes. Therefore, MdERF38 promoted anthocyanin biosynthesis in response to drought stress. Furthermore, we found that MdBT2, a negative modulator of anthocyanin biosynthesis, decreased MdERF38-promoted anthocyanin biosynthesis by accelerating the degradation of the MdERF38 protein. In summary, our data provide a mechanism of the drought stress-induced anthocyanin biosynthesis that involves dynamic modulation of MdERF38 at both transcriptional and post-translational levels.

10.
Int J Cardiol ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31521437

RESUMO

BACKGROUND: Angiotensin-(1-12) [Ang-(1-12)] is a renin-independent precursor for direct angiotensin-II production by chymase. Substantial evidence suggests that heart failure (HF) may alter cardiac Ang-(1-12) expression and activity; this novel Ang-(1-12)/chymase axis may be the main source for angiotensin-II deleterious actions in HF. We hypothesized that HF alters cardiac response to Ang-(1-12). Its stimulation may produce cardiac negative modulation and exacerbate left ventricle (LV) systolic and diastolic dysfunction. METHODS AND RESULTS: We assessed the effects of Ang-(1-12) (2 nmol/kg/min, iv, 10 min) on LV contractility, LV diastolic filling, and LV-arterial coupling (AVC) in 16 SD male rats with HF-induced by isoproterenol (3 mo after 170 mg/kg sq. for 2 consecutive days) and 10 age-matched male controls. In normal controls, versus baseline, Ang-(1-12) increased LV end-systolic pressure, without altering heart rate, arterial elastance (EA), LV end-diastolic pressure (PED), the time constant of LV relaxation (τ) and ejection fraction (EF). Ang-(1-12) significantly increased the slopes (EES) of LV end-systolic pressure (P)-volume (V) relations and the slopes (MSW) of LV stroke wok-end-diastolic V relations, indicating increased LV contractility. AVC (quantified as EES/EA) improved. In contrast, in HF, versus HF baseline, Ang-(1-12) produced a similar increase in PES, but significantly increased τ, EA, and PED. The early diastolic portion of LV PV loop was shifted upward with reduced in EF. Moreover, Ang-(1-12) significantly decreased EES and MSW, demonstrating decreased LV contractility. AVC was decreased by 43%. CONCLUSIONS: In both normal and HF rats, Ang-(1-12) causes similar vasoconstriction. In normal, Ang-(1-12) increases LV contractile function. In HF, Ang-(1-12) has adverse effects and depresses LV systolic and diastolic functional performance.

11.
Immunity ; 51(3): 522-534.e7, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31471107

RESUMO

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31478879

RESUMO

Currently, depression has become a common mental disorder and one of the main causes of disability worldwide. Due to the difference in depressive symptoms evoked by individual differences, how to design comprehensive and effective depression detection methods has become an urgent demand. This study explored from physiological and behavioral perspectives simultaneously and fused pervasive electroencephalography (EEG) and vocal signals to make the detection of depression more objective, effective and convenient. After extraction of several effective features for these two types of signals, we trained six representational classifiers on each modality, then denoted diversity and correlation of decisions from different classifiers using co-decision tensor and combined these decisions into the ultimate classification result with multi-agent strategy. Experimental results on 170 (81 depressed patients and 89 normal controls) subjects showed that the proposed multi-modal depression detection strategy is superior to the single-modal classifiers or other typical late fusion strategies in accuracy, f1-score and sensitivity. This work indicates that late fusion of pervasive physiological and behavioral signals is promising for depression detection and the multi-agent strategy can take advantage of diversity and correlation of different classifiers effectively to gain a better final decision.

13.
Adv Mater ; 31(43): e1903378, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31523873

RESUMO

Water scarcity is one of the greatest challenges facing human society. Because of the abundant amount of water present in the atmosphere, there are significant efforts to harvest water from air. Particularly, solar-driven atmospheric water generators based on sequential adsorption-desorption processes are attracting much attention. However, incomplete daytime desorption is the limiting factor for final water production, as the rate of water desorption typically decreases very quickly with decreased water content in the sorbents. Hereby combining tailored interfacial solar absorbers with an ionic-liquid-based sorbent, an atmospheric water generator with a simultaneous adsorption-desorption process is generated. With enhanced desorption capability and stabilized water content in the sorbent, this interfacial solar-driven atmospheric water generator enables a high rate of water production (≈0.5 L m-2 h-1 ) and 2.8 L m-2 d-1 for the outdoor environment. It is expected that this interfacial solar-driven atmospheric water generator, based on the liquid sorbent with a simultaneous adsorption-desorption process opens up a promising pathway to effectively harvest water from air.

14.
Cells ; 8(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374826

RESUMO

Located at the skin surface, keratinocytes (KCs) are constantly exposed to external stimuli and are the first responders to invading pathogens and injury. Upon skin injury, activated KCs secrete an array of alarmin molecules, providing a rapid and specific innate immune response against danger signals. However, dysregulation of the innate immune response of KCs may lead to uncontrolled inflammation and psoriasis pathogenesis. Keratins (KRT) are the major structural intermediate filament proteins in KCs and are expressed in a highly specific pattern at different differentiation stages of KCs. While KRT14-KRT5 is restricted to basal proliferative KCs, and KRT10-KRT1 is restricted to suprabasal differentiated KCs in normal skin epidermis, the wound proximal KCs downregulate KRT10-K1 and upregulate KRT16/KRT17-KRT6 upon skin injury. Recent studies have recognized KRT6/16/17 as key early barrier alarmins and upregulation of these keratins alters proliferation, cell adhesion, migration and inflammatory features of KCs, contributing to hyperproliferation and innate immune activation of KCs in response to an epidermal barrier breach, followed by the autoimmune activation of T cells that drives psoriasis. Here, we have reviewed how keratins are dysregulated during skin injury, their roles in wound repairs and in initiating the innate immune system and the subsequent autoimmune amplification that arises in psoriasis.

15.
Int J Biol Macromol ; 140: 1073-1083, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31465798

RESUMO

Protein from Haematococcus pluvialis (H. pluvialis) residues after pigment removal was prepared by alkaline extraction and acid precipitation. And the structural and functional properties of protein extracts were measured and analyzed. The effect of extraction conditions (liquid/solid ratio 10-20 mL/g), pH 10-12 and 25-45 °C (temperature) on the yield of H. pluvialis protein (HP) was carried out using Box-Behnken design. Under optimum extraction conditions: liquid/solid 20 mL/g, pH 11.5 and lower extraction temperature 35 °C, the highest extraction yield (81.36%) of HP was gained, which was close to the predicted value (83.32%). The HP exhibited the better functional properties. The solubility could reach 93.65% at pH 10.0; the foaming capacity and stability were 88.32 and 89.62%, respectively; the emulsifying capacity and stability were 161.52 and 48.2%, respectively; the water holding capacity (WHC) and oil absorption capacity (OAC) were 4.06 and 3.29 g/g, respectively. Fourier Transform infrared spectroscopy (FTIR) data of the HP showed the ß-sheet content (30.37%) was the maximum, while α-helix content (14.86%) was the minimum, whereas the content of amino acids was rich in HP. These results demonstrated that the HP had potential use in food industry.

16.
ACS Appl Mater Interfaces ; 11(34): 31441-31451, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31370391

RESUMO

In this work, mesostructured metal-organic frameworks (MOFs) of MIL-101-Crs with different specific surface areas were synthesized successfully under solvothermal conditions using cationic surfactant cetyltrimethyl ammonium bromide (CTAB) as a structural template. It was found that crystallinity degrees, specific surface areas, and pore size distributions strongly depended on the loading of CTAB. Nitrogen adsorption and positron annihilation lifetime spectroscopy (PALS) results showed that the mean mesopore size increased with loading more CTAB due to the formation of larger templated mesopores. Although Langmuir adsorption of both methylene blue (MB) and methyl orange (MO) was confirmed in MIL-101-Crs, the experimental results showed different adsorption behaviors for them depending on the dye molecular size, pore structure, and charge properties of dye molecules/MOFs in solution. The MB molecules were found to be mainly adsorbed in the interspaces between grains and the templated mesopores, whereas the MO molecules were adsorbed in the inherent pores as well as the templated ones in MOFs due to the unsaturated metal sites' electrostatic attraction on them. Remarkably, MO adsorption capacity was observed to be proportional to the specific surface area, which allowed one to get a good linear fitting of experimental data. Interestingly, the good consistence between the fitting experimental parameter, that is, the number of adsorbed MO-s per unit specific surface area, and the calculated one according to our rough estimation strongly suggests that MO-s are electrostatically attracted and rotating around the unsaturated metal sites on MOFs' inner surfaces, which exclude other MO-s to be adsorbed around due to the "hindering effect" of the rotating motion.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31449017

RESUMO

This paper proposes to utilize supervised deep convolutional neural networks to take full advantage of the long-term spatial-temporal information in order to improve the video saliency detection performance. The conventional methods, which use the temporally neighbored frames solely, could easily encounter transient failure cases when the spatial-temporal saliency clues are less-trustworthy for a long period. To tackle the aforementioned limitation, we plan to identify those beyond-scope frames with trustworthy long-term saliency clues first and then align it with the current problem domain for an improved video saliency detection.

18.
J BUON ; 24(3): 1175-1180, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424676

RESUMO

PURPOSE: Oridonin, a diterpenoid, has been reported to exhibit anticancer activity against a wide range of cancer types.In this study, the effect Oridonin was examined against human osteosarcoma cells. METHODS: The human osteosarcoma cells U2OS were treated with various concentrations of Oridonin from 0-200 µM for 24 h. The anti-proliferative effects of Oridonin were measured by cell viability assay. DAPI and annexin V/propidium iodide (PI) assays were employed to examine the induction of apoptosis. Transwell assay was performed to examine the cell migration and invasion. Expression analysis was performed by western blot. RESULTS: Oridonin inhibited the proliferation of U2OScells and exhibited an IC50 of 30 µM. The antiproliferative effects were mainly found to be due to induction of apoptosis as indicated by DAPI staining. Moreover, the annexin V/PI staining showed that the percentage of the apoptotic cells increased with increase in the concentration of Oridonin. The induction of apoptosis was also related with upregulation of Bax, Caspase 3 and 9 expression and downregulation of Bcl-2. Oridonin was also found to cause significant decrease in the expression of MMP-2, 3 and 9 concentration-dependently. Transwell assay showed that Oridonin inhibited the migration and invasion of the U2OS cells. CONCLUSION: It is concluded that Oridonin exhibits significant antiproliferative effects on the osteosarcoma cells and may prove essential in the development of systemic therapy for osteosarcoma.

19.
Anal Chem ; 91(17): 11467-11473, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31393110

RESUMO

In this paper, we adapt the electrochemical, aptamer-based (E-AB) sensor platform to develop colorimetric aptamer-based sensors using a closed-bipolar electrode (C-BPE) system. The C-BPE E-AB sensors provide quantitative detection of target molecules based on the rate of color change of an electrochromic Prussian blue (PB) thin-film indicator electrode. The C-BPE cathode, or sensing electrode, is modified with a redox-labeled aptamer that binds to a specific target. More specifically, we employed sequences specific for adenosine triphosphate (ATP) and tobramycin as test-bed targets because these sequences are well vetted. The C-BPE anode, or indicator electrode, was coated with an electrochromic thin film comprising Prussian white (PW) that, when reduced to PB, is accompanied by a corresponding color change used for analytical detection. The rate of color change from PW to PB is facilitated by a potassium ferricyanide-catalyzed oxidation of leucomethylene blue (LB) to methylene blue (MB), the redox label conjugated to the aptamer on the sensing electrode. We demonstrate that the rate of color change is quantitatively related to the concentration of target analyte, which provides a means for naked eye determination. When combined with smartphone-based colorimetric detection, these C-BPE E-AB sensors present a user-friendly alternative to traditional E-AB sensors that rely on voltammetric analysis and a potentiostat, opening up the possibility of point-of-use applications.

20.
Environ Int ; 131: 104994, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302480

RESUMO

There is a wide concern that emerging organic pollutants (EOPs) in surface water could adversely affect human health and wildlife. However, the geographic distribution, exposure pattern and ecological risk of emerging organic pollutants are poorly understood at a global scale. This paper provides a comprehensive survey on the exposure level of EOPs in China, the US and the EU based on the published literature. The hazard level of three categories of EOPs, namely pharmaceuticals and personal care products (PPCPs), pesticides and industrial chemicals was further evaluated by adopting a novel Aquatic HazPi index that jointly accounts for the persistence, bioaccumulation, toxicity and bioactivity. Furthermore, a correlation analysis of land use with the surface water exposure status regarding the synthetic chemicals was conducted. According to the published data reported between 2010 and 2016, the concentration of pesticides in the US was higher than in the EU and China. The concentration of PPCPs in the EU was generally lower than in both the US and China, while the concentration of industrial chemicals in China was higher than in the EU and the US. Among the chemicals whose median concentration in surface water was >10 ng/L, the antiretroviral Efavirenz, the pesticide Fipronil, and octocrylene, an industrial chemical and cosmetic ingredient, were found with the highest aquatic HazPi value. Lastly, the spatial distribution and concentration of hazardous EOPs was shown to depend on local landscape and land usages. Our study provides the first broad overview on the geographic distribution, exposure pattern of hazardous EOPs in the three major economic entities: China, the US and the EU.

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