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1.
Chemosphere ; 239: 124803, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520973

RESUMO

Nitrogen biogeochemistry occupies a central role in nitrogen cycles and exerts a significant influence on primary productivity and global carbon cycles. In order to better understand the nitrogen biogeochemistry in coastal regions, spatiotemporal nitrogen fixation, denitrification and anammox were investigated in the coastal regions of northern Beibu Gulf (NBG), South China Sea (SCS). Nitrogen fixation was mainly detected in the water column of outer bays, attributed to the low nitrate concentration and low N/P (N/P < 16). Comparisons of the nitrogen fixation rates between unicellular (<10 mm) and the filamentous diazotrophs (>10 mm) indicated that the contribution of unicellular diazotrophs was more important than filamentous diazotrophs. Besides, field investigation revealed that Richelia was the dominant species in filamentous diazotrophs. On the other hand, both denitrification and anammox were found in the surface sediment and denitrification dominated the nitrogen loss process. Denitrification was mainly related to the nitrate concentration in pore water and organic matter in the sediment, while anammox was mainly regulated by the concentration of nitrate and nitrite in pore water. Additionally, temperature, dissolved oxygen (DO) and salinity also had an impact on denitrification and anammox. The net areal yield of nitrogen biogeochemical processes was estimated to be -1079t/a, as an important pathway of nitrogen removal. This study adds to the knowledge of nitrogen biogeochemistry in the nutrient-replete coastal region and highlights its significance in such an environment.

2.
Chemosphere ; 240: 124820, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31568942

RESUMO

A novel activated primary tank (APT) with an elutriation unit was developed for recovering carbon by the fermentation and elutriation of primary sludge, and the mechanical elutriation mechanism was analysed by conducting a batch fermentation experiment to improve carbon source recovery. The results indicated that a high stirring velocity gradient could cause sludge disintegration, which could not only shorten the fermentation time, but also increase the production of soluble chemical oxygen demand (SCOD) and volatile fatty acids (VFAs) by 8.3% and 9.5%, respectively. Moreover, mechanical elutriation could also promote the release of SCOD from sludge to water, resulting in an increase in the yield of SCOD by 9.2%, it was observed that elutriation intensity plays a more important role than the elutriation time. The microbial community structure of the fermentation system was influenced by the stirring intensity. The relative abundance of fermentative bacteria in the reactor with a stirring intensity (G) of 160 s-1 was 13.8%, which was significantly higher than that in the reactor with G = 31 s-1 (8.037%), so the accumulation of VFAs and SCOD in the reactor with G = 160 s-1 was improved.

3.
J Cell Biochem ; 121(1): 25-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31433522

RESUMO

Myocardial dysfunction is an important manifestation of sepsis. In addition, inactivation of the mitogen-activated protein kinase (MAPK) signaling pathway has been reported to be beneficial in sepsis. The current study used gene expression profiling to demonstrate the overexpression of angiotensin II type 1 receptor (AT1R) and activation of the MAPK signaling pathway in sepsis. In this study, we used a rat model of sepsis established by cecal ligation and puncture to explore the mechanism of AT1R silencing in relation to the MAPK signaling pathway on myocardial injury. Various parameters including blood pressure, heart rate, and cardiac function changes were observed. Enzyme-linked immunosorbent assay was used to measure the concentration of cardiac troponin T (TnT), cardiac troponin I (cTnI), and creatine kinase isoenzyme muscle/brain (CK-MB). Myocardial enzyme, tissue antioxidant capacity, mitochondria swelling, and membrane potential were also detected. Terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling staining was applied to measure cell apoptosis, and messenger RNA and protein levels of apoptosis-related proteins (Fas ligand [Fasl], B-cell CLL/lymphoma [Bcl-2], p53) were also detected. Initially, sepsis rats exhibited decreased survival rate, but increased ejection fraction (EF), heart rate, and concentrations of TnT, cTnI, and CK-MB. Furthermore, decreased AT1R expression inactivated the MAPK signaling pathway (shown as decreased extracellular signal-regulated kinase and cyclic adenosine 3',5'-monophosphate response element binding protein expression), decreased EF, heart rate, and concentrations of TnT, cTnI, and CK-MB, but increased sepsis rat survival rate. Eventually, decreased AT1R expression inhibited myocardial cell apoptosis (shown as decreased apoptosis rate and p53 and Fasl expression as well as increased Bcl-2 expression). These findings indicated that AT1R silencing plays an inhibitory role in sepsis-induced myocardial injury by inhibiting the MAPK signaling pathway.

4.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683587

RESUMO

Zhenjiang aromatic vinegar (ZAV) is a kind of traditional fermented food worldwide. In this study, the changes of physicochemical properties, total phenolic content (TPC), total flavonoid content (TFC), and total antioxidant activity (TAA) were evaluated during the brewing process of ZAV. In addition, the correlation between phenolic compound contents and antioxidant activities was investigated during the aging process (AP) of ZAV. The results showed that total acids, non-volatile acids, and amino nitrogen increased gradually during the brewing process. Reducing sugar decreased sharply at the early fermentation stage and then increased during the AP. Meanwhile, TPC, TFC, and TAA kept a very low level at the stage of alcohol fermentation (AF), and increased to the highest level at the sixth year of the AP. TAA has a high positive correlation with TPC and TFC during the brewing process of ZAV. In addition, the contents of p-hydroxybenzoic acid, vanillic acid, and catechin were higher than other phenolic compounds and reached the highest level at the sixth year of the AP, and were the main composition of phenolic compounds during the AP. Moreover, gallic acid, ferulic acid, and sinapic acid had the higher contribution at the early stage of the AP, and then declined to a lower level. Catechin, vanillic acid, and syringic acid had a higher contribution during the AP. These findings would be helpful in controlling the quality of vinegar and improving its functional properties.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31683665

RESUMO

Dementia is a serious public health problem. The more extensive dementia knowledge is, the more conducive it is to early prevention and treatment of dementia. However, no assessment of the general population's dementia awareness has been conducted so far in China. Thus, this study assessed the national public knowledge of dementia based on mobile internet in China. We assessed 10,562 national respondents recruited based on the most popular social networking service in China, WeChat and analyzed the data using quantitative methods. The overall correct rate of total dementia knowledge was 63.14%. Only half of the participants (50.84%) could identify risk factors accurately. The level of dementia knowledge was positively associated with high education, city residency, and experience of exposure to information on dementia. The sandwich generation (aged 20-60 years) had the highest level of dementia knowledge. Chinese people were found to have a low level of knowledge about dementia, especially those aged over 60 years, with low education and living in rural areas. Further educational programs and campaigns are needed to improve dementia knowledge, with greater focus on the older population as the target audience, emphasis on dementia risk factors as educational content, correcting misconceptions about dementia, and providing more experience of exposure to dementia.

6.
Opt Express ; 27(22): 32337-32348, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684448

RESUMO

This paper proposes an achromatic annular folded lens (AFL) with a reflective-diffractive optical element (RDOE). We derive novel mathematical models of the diffraction efficiency and polychromatic integral diffraction efficiency (PIDE) of the RDOE and an expression for its microstructure height. An AFL with an RDOE made of an optical plastic substrate material is designed in the visible waveband. To minimize the influence of incident angle on the diffraction efficiency and PIDE, the microstructure height is optimized. The design results indicate that the lateral color of the AFL is corrected, the modulation transfer function considering the diffraction efficiency is larger than 0.25 at 111 cycles/mm for all field of views. The hybrid AFL outperforms the conventional refractive imaging system in terms of the system size, volume, and image quality under the same specifications. It can be used in new-generation miniaturized imaging systems.

7.
Opt Express ; 27(20): 28792-28799, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684623

RESUMO

A terahertz (THz) nonvolatile in situ electrically erasable-rewritable photo-memory based on indium oxide (In2O3) nanoparticles is reported. The In2O3/PEDOT:PSS/quartz sample increases its conductivity and attenuates its THz transmission under optical excitation. When this optical excitation is terminated, the modulated THz transmission recovers to its original value in an air environment slightly. The modulated THz transmission recovered more rapidly with increasing bias voltage. Nonvolatile digital information storage is enabled when the In2O3/PEDOT:PSS/quartz structure is encapsulated in nitrogen. The photo-memory can be rewritten after in situ electrical erasure. The results show that in situ electrically erasable terahertz nonvolatile rewritable photo-memories are feasible.

8.
Anal Chem ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31718151

RESUMO

Knowledge of the chemical identity of metabolite molecules is critical for the understanding of the complex biological systems they belong to. Since metabolite identities and their concentrations are often directly linked to the phenotype, such information can be used to map biochemical pathways and understand their role in health and disease. A very large number of metabolites however are still unknown, i.e. their spectroscopic signatures do not match those in existing databases, suggesting unknown molecule identification is both imperative and challenging. Although metabolites are structurally highly diverse, the majority shares a rather limited number of structural motifs, which are defined by sets of 1H, 13C chemical shifts of the same spin system. This allows one to characterize unknown metabolites by a divide-and-conquer strategy that identifies their structural motifs first. Here we present the structural motif-based approach "SUMMIT Motif" for the de novo identification of unknown molecular structures in complex mixtures, without the need for extensive purification, using NMR in tandem with two newly curated NMR molecular structural motif metabolomics databases (MSMMDB). In identifying structural motif(s), first the 1H and 13C chemical shifts of all the individual spin systems are extracted from 2D and 3D NMR spectra of the complex mixture. Next, the molecular structural motifs are identified by querying these chemical shifts against the new MSMMDBs. One database, COLMAR MSMMDB, was derived from experimental NMR chemical shifts of known metabolites taken from the COLMAR metabolomics database, while the other MSMMDB, pNMR MSMMDB, is based on empirically predicted chemical shifts of metabolites of several existing large metabolomics databases. For molecules consisting of multiple spin systems, spin systems are connected via a long-range scalar J-coupling NMR experiment. When this motif-based identification method was applied to the hydrophilic extract of mouse bile fluid, two unknown metabolites could be successfully identified. This approach is both accurate and efficient for the identification of unknown metabolites and hence contribute to the understanding of human health and disease.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31713959

RESUMO

Black phosphorene has attracted much attention as a semiconducting two-dimensional material. Violet phosphorus is another layered semiconducting phosphorus allotrope with unique electronic and optoelectronic properties. However, no confirmed violet crystals or reliable lattice structure of violet phosphorus has been obtained. The further exploration of violet phosphorus and violet phosphorene are restricted. The violet phosphorus single crystal has been produced and the lattice structure has been obtained by single-crystal x-ray diffraction to be monoclinic with space group of P 2/n (13) (a=9.210, b=9.128, c=21.893 Å, ß=97.776°). The lattice structure obtained has been confirmed to be reliable and stable compared with the well adopted one by dynamical stability investigation. The optical bandgap of the violet phosphorus was measured to be around 1.7 eV, consistent with the calculated one. The thermal decomposition temperature of violet phosphorus was measured to be 52 °C higher than its black phosphorus counterpart which was assumed to be the most sable one, indicating that violet phosphorus is the most stable phosphorus allotrope. The violet phosphorene was easily obtained by both mechanical and solution exfoliation under ambient conditions.

10.
ACS Chem Neurosci ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31682397

RESUMO

Morphine tolerance is a classic, challenging clinical issue. However, the mechanism underlying this phenomenon remains poorly understood. Recently, studies have shown that ferroptosis correlates with drug resistance. Therefore, this study investigated whether spinal cord ferroptosis contributes to morphine tolerance. C57BL/6 mice were continuously subcutaneously injected with morphine, with or without the ferroptosis inhibitor liproxstatin-1. We found that chronic morphine exposure led to morphine antinociception tolerance, accompanied by loss of spinal cord neurons, increase in the levels of iron, malondialdehyde, and reactive oxygen species, and decreases in the levels of superoxide dismutase. Additionally, inflammatory response and mitochondrial shrinkage, processes that are involved in ferroptosis, were observed. Simultaneously, we found that 10 mg/kg of liproxstatin-1 could alleviate iron overload by balancing transferrin receptor protein 1/ferroportin expression and attenuate morphine tolerance by increasing glutathione peroxidase 4 levels, while reducing the levels of malondialdehyde and reactive oxygen species. It also downregulated the expression of extracellularly regulated protein kinases that had been induced by chronic morphine exposure. Our results indicate that spinal cord ferroptosis contributes to morphine tolerance, while liproxstatin-1 attenuates the development of morphine tolerance. These findings suggest that ferroptosis may be a potential therapeutic target for morphine tolerance.

11.
J Stroke Cerebrovasc Dis ; : 104468, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31694784

RESUMO

OBJECTIVES: Intracerebral hemorrhage (ICH) is one of the leading causes of disability and mortality in adult, which lacks effective therapies. Edaravone has showed its neuroprotective effects after ischemia stroke, but its effects and possible mechanisms after ICH are poorly understood. Here, we investigated whether edaravone confers neuroprotection after ICH in rats and explored the potential mechanisms involved. METHODS: ICH was induced in the right basal ganglia of Sprague-Dawley rats by stereotacticly injection of 200 µl autologous blood. Edaravone (3 mg/kg) or vehicle (saline) was administered intravenously and NLRP3 selective antagonist (MCC950, 10 mg/kg) was intraperitoneally injected to study the potential mechanism. Water Morris Maze Test and Rotarod test were used to elucidate neurological function and Fluoro-Jade C was used to study neurodegeneration after ICH. Western blot assay, Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunohistochemistry were used to check the expression of molecules involved. RESULTS: As a result, we found that edaravone significantly alleviated brain edema and conferred the neurological deficits of rats after ICH. Hematoma increased NLRP3 expression in microglia, which was decreased by edaravone. Moreover, we demonstrated that edaravone shared a similar effect with MCC950 on alleviating neurodegeneration and decreasing the expression of IL-1ß, Caspase 1 and NF-κB in protein or mRNA. Lastly, edaravone and MCC950 both increased the number of Tuj-1 positive neuronal cells peripheral hematoma. CONCLUSIONS: The present study demonstrated that edaravone conducted neuroprotection after ICH partially via suppressing NF-κB-dependent NLRP3 in microglia, which contributed a novel evidence for clinic usage of edaravone after ICH.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31690994

RESUMO

PURPOSE: Tunnel enlargement and graft rupture are common complications associated with ACL reconstruction (ACLR). This study aims to explore how variations in graft stiffness and shape affect the strain energy density (SED) around bone tunnel entrances and stress on the graft and subsequently influencing the level of tunnel enlargement and graft wear. METHODS: Finite element ACLR models were developed using different graft stiffnesses (323 N/mm, 545 N/mm and 776 N/mm) and shapes (circular and elliptical). The models were subjected to a combined loading of 103 N anterior tibial load, 7.5 Nm internal tibial moment, and 6.9 Nm valgus tibial moment at joint flexion of 30°. SED at tunnel entrances and stresses on the graft was recorded and compared among the different models. RESULTS: Increasing the graft stiffness resulted in greater stress on the graft (17.2, 24.4 and 31.7 MPa for graft stiffnesses of 323 N/mm, 545 N/mm and 776 N/mm), but had little effect on the SED reduction around the tunnel entrances. Changing the cross section of the graft from circular to elliptical caused an additional reduction in SED (56.8 vs 2.8 kJ/m3) at the posterior zone of the femoral tunnel entrance and increased the stress on the graft (31.7 MPa vs 38.9 MPa). CONCLUSIONS: This study recommends using ACL grafts with lower stiffness and a circular cross section to reduce tunnel enlargement and graft wear following ACLR.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31699591

RESUMO

In this work, a primary method was constructed for detecting hydrazine in plant, thus accomplished the closed-loop monitoring of hydrazine circulation within manufacture, environment, plants, animals and human. From a series of sensors, QYL-1 was selected to present the hydrazine sensing properties. As a preliminary tool, QYL-1 suggested the ultra-wide linear range (0-20.0 equivalent) and high selectivity, which were extremely essential for linking the monitoring in various scale and field. For the first time, concentration-dependent tracking of hydrazine was successfully performed in Arabidopsis Thaliana root tips. Afterwards applications in water samples and living MCF-7 cells then fulfilled the demonstration of closing the loop by linking both the upstream and downstream nodes. More than raising a practical method, this work offered initial information for the closed-loop monitoring of hydrazine circulation, which might be significant for the ideal systematic managing in future.

14.
Chembiochem ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31702879

RESUMO

The activation of toll like receptors (TLRs) plays important roles in the immune response. The ability to control the activities of TLRs could be used as a switch for immune response. Herein, we rationally designed and synthesized a photoswitchable Pam3CSK4 derivative (P10) to control the activation of TLR1/2. The ground state trans-P10 could stimulate and activate antigen-presenting cells (APCs) through promoting the TLR1/2 dimerization. However, the cis-P10, derived from UV irradiation of trans-P10, reduced the activities of APCs by impeding the TLR1/2 dimerization. In the absence of UV radiation, the cis-P10 slowly returned to its ground trans state, restoring the activities of the APCs stimulating. Our results indicated that the optical control of TLR1/2 dimerization mediated by the photoswitchable P10 holds potential to regulate the immune activation and inflammation.

15.
J Cell Mol Med ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755219

RESUMO

Myocardial infarction (MI) remains the leading cause of morbidity and mortality worldwide, and novel therapeutic targets still need to be investigated to alleviate myocardial injury and the ensuing maladaptive cardiac remodelling. Accumulating studies have indicated that lncRNA H19 might exert a crucial regulatory effect on cardiovascular disease. In this study, we aimed to explore the biological function and molecular mechanism of H19 in MI. To investigate the biological functions of H19, miRNA-22-3p and KDM3A, gain- and loss-of-function experiments were performed. In addition, bioinformatics analysis, dual-luciferase reporter assays, RNA immunoprecipitation (RIP) assays, RNA pull-down assays, quantitative RT-PCR and Western blot analyses as well as rescue experiments were conducted to reveal an underlying competitive endogenous RNA (ceRNA) mechanism. We found that H19 was significantly down-regulated after MI. Functionally, enforced H19 expression dramatically reduced infarct size, improved cardiac performance and alleviated cardiac fibrosis by mitigating myocardial apoptosis and decreasing inflammation. However, H19 knockdown resulted in the opposite effects. Bioinformatics analysis and dual-luciferase assays revealed that, mechanistically, miR-22-3p was a direct target of H19, which was also confirmed by RIP and RNA pull-down assays in primary cardiomyocytes. In addition, bioinformatics analysis and dual-luciferase reporter assays also demonstrated that miRNA-22-3p directly targeted the KDM3A gene. Moreover, subsequent rescue experiments further verified that H19 regulated the expression of KDM3A to ameliorate MI-induced myocardial injury in a miR-22-3p-dependent manner. The present study revealed the critical role of the lncRNAH19/miR-22-3p/KDM3A pathway in MI. These findings suggest that H19 may act as a potential biomarker and therapeutic target for MI.

16.
Orthop Surg ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755233

RESUMO

OBJECTIVE: To compare the efficacy of the restoration of tibial component coronal alignment with a double-check technique and the conventional surgical technique during total knee arthroplasty (TKA) in knee osteoarthritis patients, and to investigate the distribution of the medial proximal tibial angle (MPTA) after TKA. METHODS: A retrospective review was performed of 151 patients (179 knees) with knee osteoarthritis undergoing primary TKA in Beijing Chaoyang Hospital, Capital Medical University from February 2013 to January 2015 to evaluate the differences in MPTA in patients undergoing the conventional TKA and those undergoing a modified TKA with a double-check technique after the surgery. All patients were evaluated by MPTA, range of motion (ROM), Knee Society Clinical Rating System (KSS) clinical scores, and KSS functional scores. An MPTA deviation of 3° or greater was considered malalignment. RESULTS: A total of 130 TKA procedures in 119 patients were included in the study: 64 knees treated with conventional TKA and 66 knees treated with the double-check technique TKA. The mean postoperative MPTA was 88.6° ± 2.2° in the conventional TKA group and 89.1° ± 1.5° in the double-check TKA group. The mean postoperative MPTA between the two groups was not significantly different. In the conventional TKA group, 79.7% (51 knees) had a postoperative MPTA deviation within 3° and 20.3% (13 knees) had a MPTA deviation greater than 3°. In the double-check TKA group, 93.9% (62 knees) had a postoperative MPTA deviation within 3°and 6.1% (4 knees) had a MPTA deviation greater than 3°. The postoperative MPTA deviation within 3° showed a statistically significant difference between the two groups. In the double-check TKA group, a 21.2% (14 knees) tibial malalignment was detected after the first check and a 9.1% (6 knees) tibial malalignment was detected after the second check. The mean postoperative ROM was 118.1° ± 9.2° in the conventional TKA group and 115.7° ± 10.1° in the double-check TKA group. The mean postoperative KSS clinical score was 89.3 ± 3.5 in the conventional TKA group and 89.0 ± 3.7 in the double-check TKA group. The mean postoperative KSS functional score was 84.8 ± 10.0 in the conventional TKA group and 84.9 ± 9.0 in the double-check TKA group. The mean postoperative ROM, KSS clinical scores, and KSS functional scores between the two groups were not statistically significantly different. CONCLUSION: Malalignment of the tibial component can occur after conventional TKA, and the double-check technique is an effective method to improve tibial component coronal alignment.

17.
Eur J Pharmacol ; : 172787, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31712061

RESUMO

Zinc finger E-box binding homeobox 1 (ZEB1) (previously known as TCF8), a transcriptional repressor, is a member of the zinc-finger family of proteins. Numerous studies have demonstrated that abnormal expression of ZEB1 in many types of liver disease including hepatocellular carcinoma (HCC). Liver fibrosis is the basis and central link in the progression of liver disease. Thereby, the function of ZEB1 in liver fibrosis has been investigated. The aim of the present study was to investigate the role of ZEB1 in liver fibrosis and to elucidate the mechanism. In this study, we explored the effect of ZEB1 in hepatic stellate cells (HSCs) activation and the regulatory mechanism of the Wnt/ß-catenin signaling pathway. Additionally, ZEB1 positively regulated the expression levels of α-SMA and Col.I in vivo and in vitro, which were correlated with the activated HSCs. Furthermore, overexpression of ZEB1 could inhibit HSCs apoptosis and promote IL-6 and TNF-α secretion in LX-2 cells. Conversely, ZEB1 silencing led to the promotion of cell proliferation and the reduction of IL-6 and TNF-α secretion in LX-2 cells. Mechanically, canonical Wnt/ß-catenin signaling pathway could be regulated by ZEB1. Collectively, the data suggested that ZEB1 might play a significant role in the activation of LX-2 cells, and Wnt/ß-catenin signaling pathway might participate in this progression.

18.
Luminescence ; 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31736184

RESUMO

Based on the chemiluminescence (CL) phenomenon of peroxymonosulfate (PMS) and Tb(III) enhanced by its ligand in a micelle microenvironment, a fast and sensitive flow injection CL method for PMS detection was proposed and applied to the analysis of different samples and PMS decomposition. Under the optimized conditions, a linear range was obtained from 4.0 × 10-6  mol L-1 to 2.0 × 10-4  mol L-1 with a high correlation coefficient (r = 0.9997), detection limit of 5.0 × 10-7  mol L-1 (S/N = 3) and relative standard deviation of 2.4% for 1.0 × 10-5  mol L-1 PMS (n = 9). This was successfully applied to the determination of PMS in Virkon powder, tap water, and swimming pool water samples with satisfactory recoveries from 94.8% to 104.8%. In particular, the analytical frequency could be as fast as five samples per minute because there was no reaction step before analysis and the CL phenomenon was instantaneous. Therefore, this CL method has also been successfully applied to investigate the PMS decomposition profiles in carbon material (carbon nanotubes, carbon nanofibres, activated carbon and graphene oxide) catalysis systems, which followed pseudo-first-order kinetics with good correlation coefficients (r > 0.9305). Quenching experiments and electron spin resonance spectra verified that the CL phenomenon was due to the formation of singlet oxygen, and that hydroxyl and sulfate radicals might be important in the generation of singlet oxygen. Tb(III) is the luminescent emitter according to the characteristics emission bands of the fluorescence and CL spectra in different media.

19.
Mikrochim Acta ; 186(12): 746, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691865

RESUMO

Well-dispersed and graft-crosslinked gold nanoparticles (AuNPs) were synthesized by the reduction of tetrachloroaurate with hydrazine at room temperature. The AuNPs possess a high density of surface defects which is due to grafting of n-octanoic acid to polyvinylpyrrolidone. The physical and chemical properties of the resulting AuNPs were characterized by UV-vis, XRD, TEM/HRTEM, SAED, and XPS, respectively. The modified AuNPs were placed on a glassy carbon electrode (GCE) in an electropolymerized taurine layer to obtain a sensitive, selective, stable and rapid electrochemical dopamine sensor. The peak current, typically measured at 0.17 V (vs. SCE), increases linearly in the 1.0 to 120 µM dopamine concentration range, and the limit of detection (at S/N = 3) is 0.16 µM with a sensitivity of 2.94 µA·µM-1·cm-2. The sensor was successfully applied to the determination of dopamine in injections and spiked serum samples. The recoveries from spiked serum samples range from 97.5 to 102.4%, with RSDs ranging between 2.8 and 3.4%. Graphical abstract Schematic representation of a glassy carbon electrode modified with in-situ graft-crosslinked gold nanoparticles combined with an electropolymerized polytaurine membrane. The sensor exhibits excellent features towards dopamine determination.

20.
J Cosmet Dermatol ; 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31709745

RESUMO

BACKGROUND: Pretibial dystrophic epidermolysis bullosa (DEB-Pt) is an extremely rare subtype of dystrophic epidermolysis bullosa (DEB) characterized by blistering and scar formation. The pathogenesis of the disease is mainly due to the mutation of COL7A1 gene encoding type VII collagen fibers, resulting in the destruction of the anchoring structure of the epidermis and dermis. AIMS: The purpose of this study was to discover the major mutations in DEB-Pt by studying this family and reviewing the literature on DEB-Pt. PATIENTS/METHODS: We examined the patients by clinical manifestations and histopathology, extracted DNA from blood samples from 7 individuals in the family via FlexiGene DNA Kit, and then sequenced the samples using whole-exon sequencing (WES). RESULT: Characteristic clinical manifestations such as blisters and scars were found in the patients. Genetic analysis revealed a missense mutation in exon 87(c.6860G>A) of COL7A1 gene, which has never been reported before. CONCLUSION: The discovery of the new mutation extends the COL7A1 mutation database. We also reviewed all the mutation in DEB-Pt from relevant literature at home and abroad. This will facilitate the molecular diagnosis, treatment, and prognosis of DEB-Pt.

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