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1.
Carbohydr Polym ; 251: 117100, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33142638

RESUMO

The objective of this study was to develop a new hydrophobic film based on konjac glucomannan and kappa-carrageenan (KGM-KC) incorporating camellia oil (CO) (2, 4, and 6 %). CO was directly emulsified as a dispersed phase into KGM-KC matrix. The physical, structural, and water barrier properties of the film were studied. The results of Fourier transform infrared and scanning electron microscopy suggested that CO was successfully distributed in KGM-KC matrix by emulsification. Contact angle of the film indicated that addition of CO increased the hydrophobicity and water-resistance properties of film, which corresponding to the moisture content, total soluble mass, water vapor permeability, water vapor adsorption kinetics and water vapor adsorption isotherms. Addition of CO by emulsification improved thermal stability of film, optical properties, and mechanical properties. In conclusion, the incorporation of CO by emulsification is an effective and promising pathway to improve the properties of polysaccharide-based film.

2.
J Ethnopharmacol ; 265: 113195, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32800930

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Apigenin is a natural flavonoid compound present in chamomile (Matricaia chamomilla L.) from the Asteraceae family, which is used in the treatment of cardiovascular diseases by traditional healers, but its effects on differentiation and extracellular matrix (ECM) production of cardiac fibroblasts (CFs) induced by transforming growth factor beta 1 (TGF-ß1) are poorly understood. AIM OF THE STUDY: This study aimed to examine these effects and potential molecular mechanisms and to provide a new application of apigenin in the prevention and treatment of cardiac fibrosis. MATERIALS AND METHODS: The TGF-ß1-stimulated CFs or the combination of TGF-ß1-stimulated and microRNA-155-5p (miR-155-5p) inhibitor- or mimic-transfected CFs were treated with or without apigenin. The expression levels of intracellular related mRNA and proteins were detected by real-time polymerase chain reaction and Western blot methods, respectively. The luciferase reporter gene containing cellular Sloan-Kettering Institute (c-Ski) wild or mutant type 3'-UTR was used and the luciferase activity was examined to verify the direct link of miR-155-5p and c-Ski. RESULTS: After treatment of TGF-ß1-stimulated CFs with 6-24 µM apigenin, the expression of c-Ski was increased, while levels of miR-155-5p, α-smooth muscle actin, collagen Ⅰ/Ⅲ, Smad2/3, and p-Smad2/3 were decreased. After transfection of CFs with the miR-155-5p inhibitor or mimic, the similar or inverse results were respectively observed as well. The combination of TGF-ß1 and miR-155-5p inhibitor or mimic might cause an antagonistical or synergistic effect, respectively, and apigenin addition could enhance the effects of the inhibitor and antagonize the effects of the mimic. Luciferase reporter gene assay demonstrated that c-Ski was a direct target of miR-155-5p. CONCLUSION: These findings suggested that apigenin could inhibit the differentiation and ECM production in TGF-ß1-stimulated CFs, and its mechanisms might partly be attributable to the reduction of miR-155-5p expression and subsequent increment of c-Ski expression, which might result in the inhibition of Smad2/3 and p-Smad2/3 expressions.

3.
Mycologia ; : 1-23, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175671

RESUMO

Four epitypes and three new species of Amanita (Amanitaceae, Agaricales, Agaricomycetes, Basidiomycota) are described from Guineo-Congolian rainforests of Cameroon. Amanita echinulata, A. fulvopulverulenta, A. robusta, and A. bingensis are epitypified based on collections that are the first since the species were described nearly a century ago. Morphological features of the epitypes are described and enumerated. Amanita minima, Amanita luteolamellata, and A. goossensfontanae are described as new and added to the known macromycota of tropical Africa. Habit, habitat, and known distribution are provided for each species. Sequence data for the internal transcribed spacer (ITS) locus are provided for types and other collections of all taxa, and a molecular phylogenetic analysis across the genus Amanita corroborates morphology-based infrageneric placement for each.

4.
Biol Psychiatry ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-33183762

RESUMO

BACKGROUND: Dentate gyrus (DG), a "gate" that controls information flow into the hippocampus, plays important roles in regulating both cognitive (e.g., spatial learning and memory) and mood behaviors. Deficits in DG neurons contribute to the pathogenesis of not only neurological, but also psychiatric, disorders, such as anxiety disorder. Whereas DG's function in spatial learning and memory has been extensively investigated, its role in regulating anxiety remains elusive. METHODS: Using c-Fos to mark DG neuron activation, we identified a group of embryonic born dorsal DG (dDG) neurons, which were activated by anxiogenic stimuli and specifically express osteocalcin (Ocn)-Cre. We further investigated their functions in regulating anxiety and the underlying mechanisms by using a combination of chemogenetic, electrophysiological, and RNA-sequencing methods. RESULTS: The Ocn-Cre+ dDG neurons were highly active in response to anxiogenic environment but had lower excitability and fewer presynaptic inputs than those of Ocn-Cre- or adult born dDG neurons. Activating Ocn-Cre+ dDG neurons suppressed anxiety-like behaviors and increased adult DG neurogenesis, whereas ablating or chronically inhibiting Ocn-Cre+ dDG neurons exacerbated anxiety-like behaviors, impaired adult DG neurogenesis, and abolished activity (e.g., voluntary wheel running)-induced anxiolytic effect and adult DG neurogenesis. RNA-sequencing screening for factors induced by activation of Ocn-Cre+ dDG neurons identified BDNF, which was required for Ocn-Cre+ dDG neurons mediated antianxiety-like behaviors and adult DG neurogenesis. CONCLUSIONS: These results demonstrate critical functions of Ocn-Cre+ dDG neurons in suppressing anxiety-like behaviors but promoting adult DG neurogenesis, and both functions are likely through activation of BDNF.

5.
J Cell Physiol ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33184860

RESUMO

Morphine, a mu-opioid receptor (MOR) agonist, has been extensively used to treat advanced cancer pain. In particular, in patients with cancer metastasis, both morphine and anticancer drugs are given simultaneously. However, evidence showed that morphine might be a risk factor in promoting the tumor's malignant potential. In this study, we report that treatment with morphine could activate MOR and lead to the promotion of proliferation, migration, and invasion in HCT116 and DLD1 colorectal cancer (CRC) cells with time-concentration dependence. Moreover, morphine can also contribute to cetuximab's drug resistance, a targeted drug widely used to treat advanced CRC by inducing the activation of epidermal growth factor receptor (EGFR). The cell phenotype includes proliferation, migration, invasion, and drug resistance, which may be reversed by MOR knockdown or adding nalmefene, the MOR receptor antagonist. Receptor tyrosine kinase array analysis revealed that morphine selectively induced the transactivation of EGFR. EGFR transactivation resulted in the activation of ERK1/2 and AKT. In conclusion, morphine induces the transactivation of EGFR via MOR. It activates the downstream signal pathway AKT-MTOR and RAS-MAPK, increases proliferation, migration, and invasion, and promotes resistance to EGFR inhibitors in a CRC cell line. Furthermore, we verified that EGFR inhibition by cetuximab strongly reversed the protumoral effects of morphine in vitro and in vivo. Collectively, we provide evidence that morphine-EGFR signaling might be a promising therapeutic target for CRC patients, especially for cetuximab-resistant CRC patients.

6.
J Pediatr Nurs ; 57: 43-49, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33221696

RESUMO

BACKGROUND: Magnet®-designated hospitals are seeking to reduce the frequency of falls that lead to injury, which is considered a hospital-acquired condition. Patients with cancer are at high risk to fall, due to multiple factors. Synthesis of the literature supports team efforts and shared learning sessions for patient-care staff as part of the fall prevention process. The purpose was to improve collaboration between Registered Nurses (RNs) and Senior Nurse Aides (SNAs), as well as to enhance their knowledge of fall risk factors and evidence-based prevention guidelines for pediatric oncology patients. METHODS: An evidence-based practice project was implemented using a quality improvement pilot based on the Magnet® framework. Oncology RNs and SNAs at a large pediatric hospital were invited to attend one of five educational sessions. Pre-and post-session learning was assessed based on an adapted fall risk knowledge assessment tool. FINDINGS: Thirty participants attended an educational session with 27 (25 RNs and 2 SNAs) matched pre- and post-session assessments. Median post-session assessment scores were statistically significantly higher than pre-session scores (Z =  -3.11, p = 0.001). Overall knowledge scores increased for 63% of participants. DISCUSSION: An educational intervention focused on pediatric oncology nursing enhanced knowledge of patient-care roles and fall prevention efforts, leading to improved fall outcomes. APPLICATION TO PRACTICE: Ensuring that RNs and SNAs fully embrace their shared role in harm prevention is vital when considering the complexity of delivering nursing care in our current healthcare environment.

7.
Phys Chem Chem Phys ; 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33226034

RESUMO

We herein aim to probe the emission quenched by O2 on silica gel. Our special focus is on the O2 quenching of the fluorescence of a series of organic D-π-A phosphonium compounds 1-3. The results show that the O2 quenching rate constants for the fluorescence of 1-3 are on the order of 1010 M-1 s-1, which are nearly on the same order as those measured for 1-3 and common organic compounds in solution. In yet another approach, the study of O2 quenching of phosphorescence in the solid phase indicates that the O2 quenching rate constant for the triplet state, i.e., , is smaller than by two orders of magnitude. Detailed investigation indicates that this distinction stems from the intrinsic O2 quenching rate constants for the singlet and triplet states subsequent to the formation of collisional complexes. In the absence of the solvent cage effect, is greatly influenced by the formation energy of the O2-dye CT complex, whereas in the solid phase is a nearly diffusion-controlled rate. Due to the larger distinction between and in the solid phase, O2 quenching of fluorescence is efficient for dyes in the solid phase. This leads to a feasible application of sensing O2 with regular fluorescent dyes adsorbed on porous solid substrates.

8.
Zhongguo Zhong Yao Za Zhi ; 45(19): 4652-4657, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33164429

RESUMO

High performance liquid chromatography-ultraviolet(HPLC-UV) fingerprint is one of the most important methods for the quality control of Chinese medicines in Chinese Pharmacopoeia. However, certain subjectivity is present in selection of specific band of UV, and the inherent quality differences of Chinese medicine can't be well characterized by this method. Therefore, with different grades of Scrophulariae Radix were taken as the research object in this study, a new quality control model of HPLC-UV was established in this study based on the ultraviolet full-wavelength scanning spectrum. Firstly, different grades of Scrophulariae Radix samples were collected, and the full-wavelength ultraviolet absorption spectra of all the samples were established at the bands of 200-400 nm. In order to analyze the differences among samples, the analysis model was built following multivariate statistical analysis methods such as principal component analysis(PCA) and partial least squares discrimination analysis(PLS-DA) after the pretreatment of spectral data. The result showed that the ultraviolet band at 251 nm may contribute most to distinguish the quality differences among different grades of samples. Then, the HPLC fingerprints of samples were established with the band at 251 nm. The multivariate statistical analysis showed that there was a more significant classification trend in HPLC fingerprints than that in the original UV fingerprints, which could be used to distinguish different grades of samples, and could better reflect the differences among different grades. The method reported in this study can be of a great guidance and reference for the establishment of specific fingerprints of Chinese medicines as well as for the quality control of Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Raízes de Plantas , Análise de Componente Principal , Controle de Qualidade
9.
Zhongguo Zhong Yao Za Zhi ; 45(19): 4705-4711, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33164436

RESUMO

To explore the effect of Fuke Qianjin Capsules on anti-endometrial fibrosis in intrauterine adhesion(IUA) rats through TGF-ß1-PI3 K/Akt signaling pathway. With female SD rats as the object, IUA rat models were established through mechanical injury and infection, and they were randomly divided into normal group, sham operation group, Bujiale group(0.63 mg·kg~(-1)·d~(-1)), and high-dose Fuke Qianjin Capsules group(1.008 g·kg~(-1)·d~(-1)), medium-dose Fuke Qianjin Capsules group(0.504 g·kg~(-1)·d~(-1)), low-dose Fuke Qianjin Capsules group(0.252 g·kg~(-1)·d~(-1)). The rats were sacrificed 21 days after drug administration, and the uterus and liver were removed after blood collection from the abdominal aorta. The morphology of the uterus was observed with the naked eyes; the pathological and morphological changes of the uterine tissue and liver were observed by HE staining; the degree of fibrosis of the uterine tissue was observed by Masson staining; the expressions of TGF-ß1, TNF-α and IL-6 in serum were detected; the expressions of TGF-ß1, PI3 K, Akt, p-Akt protein in uterine tissue were detected by Western blot. The results showed that Fuke Qianjin Capsules could improve the pathological changes of uterine tissues in IUA rats, without damage to liver tissues, and reduce the expressions of TGF-ß1, TNF-α and IL-6 in serum(P<0.01); significantly reduce TGF-ß1, PI3 K, p-Akt protein expression in uterine tissues(P<0.05, P<0.01). It is indicated that Fuke Qianjin Capsules could exert the anti-endometrial fibrosis effect by regulating the TGF-ß1-PI3 K/Akt signal pathway, so as to achieve the effect in treating IUA rats, especially with the best effect in medium-dose Fuke Qianjin Capsules group.


Assuntos
Medicamentos de Ervas Chinesas , Fator de Crescimento Transformador beta1 , Animais , Cápsulas , Feminino , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética
10.
Sensors (Basel) ; 20(20)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050252

RESUMO

Silver nanoplates (AgP) were prepared and used in a colorimetric method for the evaluation of Xanthine (Xan) in blood plasma and fish meat. The detection mechanism for Xan was observed to occur via etching of AgP particles/aggregation/fusion steps, resulting in a color change from blue to grey. First, the basic Xan solution is adsorbed through partial substitution of capping molecules around the AgP with Xan, and then intermolecular hydrogen bonds form between AgP and AgP. Subsequently, the titrant Xan solution further etches the AgP and finally fuses particles together. Owing to the step by step mechanism, the response range towards Xan has two linear regression ranges: 0.15-0.60 µM and 0.61-3.00 µM, respectively. The detection limit in the range of 0.15-0.60 µM is 0.011 µM (S/N = 3). AgP exhibits good selectivity for Xan over other potential interferents such as amino acids and blood proteins. AgP achieves rapid detection of Xan and can be applied to the satisfactory determination of Xan in blood plasma and fish meat. This colorimetric sensor is easy to use, cost effective, fast, selective and user friendly.

11.
Molecules ; 25(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007982

RESUMO

The discovery of IDO1 and HDAC1 dual inhibitors may provide a novel strategy for cancer treatment by taking advantages of both immunotherapeutic and epigenetic drugs. In this paper, saprorthoquinone (1) and 13 of its analogues from Salvia prionitis Hance were investigated for their SAR against IDO1, the results demonstrated the ortho-quinone was a key pharmacophore. Then a series of IDO1 and HDAC dual inhibitors connected by appropriate linkers were designed, synthesized, and evaluated from the hit compound saprorthoquinone (1). Among them, compound 33d showed balanced activity against both IDO1 (IC50 = 0.73 µM) and HDAC1 (IC50 = 0.46 µM). Importantly, the structure of 33d suggested that an ortho-quinone pharmacophore and a N-(2-aminophenyl) amide pharmacophore were necessary for the IDO inhibition and HDAC inhibition respectively. Meanwhile, these two pharmacophore groups should be combined by a pentane linker. Moreover, the binding modes of 33d to the enzyme active site showed that the hydrogen bond with Leu234 of IDO1 appeared to confer increased potency to this class of inhibitors, which may explain the higher activity of 33d. This study provides a new strategy for future IDO1/HDAC dual inhibitors with synergistic antitumor activity started from lead compound 33d.

12.
Nanoscale Horiz ; 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33052993

RESUMO

Potassium ion hybrid capacitors (KIHCs) have drawn growing interest owing to their outstanding energy density, power density and excellent cycling stability. However, the large ionic radius of potassium triggers a huge volume change during continuous K+ insertion/extraction processes, restricting the development of KIHCs. Here, we report N-doped carbon nanotubes (NCNTs) for high-performance K+ storage. The NCNTs possess a hierarchical structure and N functional groups and not only offer sufficient space to relieve the volume expansion, but also provide highly efficient channels to transport electrons and ions. As a result, the NCNTs anode presents a high specific capacity and an excellent cycling stability with an average decay rate of 0.0238% per cycle (the lowest value among the reported carbon-based anodes for K-ions batteries) during 3600 continuous cycles. A potassium ion hybrid capacitor (KIHC) was also designed with the NCNT anode and a commercial active carbon cathode and achieved both a high energy/power density (117.1 W h kg-1/1713.4 W kg-1) and a long cycle life (2000 cycles at 1 A g-1). Moreover, the in situ Raman and ex situ element mapping characterization demonstrate the outstanding electrochemical reversibility of the NCNTs. This work provides a superior strategy to design low-cost anode materials with excellent K+ storage electrochemistry.

13.
Artigo em Inglês | MEDLINE | ID: mdl-33109908

RESUMO

Apart from respiratory symptoms, encephalopathy and a range of central nervous system complications have been described in COVID-19 (Coronavirus Disease 2019). However, there is a lack of published literature on the rehabilitative course and functional outcomes of severe COVID-19 with encephalopathy. Additionally, the presence of subclinical neurocognitive sequelae during post-acute rehabilitation has not been described and may be under-recognized by rehabilitation providers. We report the rehabilitative course of a middle-aged male patient with severe COVID-19 who required intensive care and mechanical ventilation. During post-acute inpatient rehabilitation for severe ICU-related weakness, an abnormal cognitive screen prompted brain MRI imaging which revealed destructive leukoencephalopathy. Subsequently, detailed psychometric evaluation revealed significant impairments in the domains of processing speed and executive function. After 40 days of intensive inpatient rehabilitation, he was discharged home with independent function. This report highlights the need for an increased awareness of covert subclinical neurocognitive sequalae, the role of comprehensive rehabilitation and value of routine cognitive screening therein; and describes the neurocognitive features in severe COVID-19.

14.
J Mater Chem B ; 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33112350

RESUMO

Docetaxel-based chemotherapy for prostate cancer is the clinical standard of care. However, nonspecific targeting, multiple drug resistance, and adverse side effects are common obstacles. Various natural compounds, including epigallocatechin-3-gallate (EGCG) in combination with taxane, have the potential to be developed as anticancer therapeutics. Although synergistic hydrophobic-hydrophilic combination drugs have been used with some success, the main drawbacks of this approach are poor bioavailability, unfavorable pharmacokinetics, and low tissue distribution. To improve their synergistic effect and overcome limitations, we encapsulated EGCG and low-dose docetaxel within TPGS-conjugated hyaluronic acid and fucoidan-based nanoparticles. This approach might facilitate simultaneous target-specific markers at the edge and center of the tumor and then might increase intratumoral drug accumulation. Additionally, the successful release of bioactive combination drugs was regulated by the pH-sensitive nanoparticles and internalization into prostate cancer cells through CD44 and P-selectin ligand recognition, and the inhibition of cell growth via induced G2/M phase cell cycle arrest was observed in in vitro study. In in vivo studies, treatment with cancer-targeted combination drug-loaded nanoparticles significantly attenuated tumor growth and increased M30 protein expression without causing organ damage. Overall, the multifunctional nanoparticle system improved the drugs' synergistic effect, indicating great potential in its development as a prostate cancer treatment.

15.
Radiology ; 297(3): 622-629, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33078998

RESUMO

Background CT and bone scintigraphy have limitations in evaluating systemic anticancer therapy (SACT) response in bone metastases from metastatic breast cancer (MBC). Purpose To evaluate whether whole-body MRI enables identification of progressive disease (PD) earlier than CT and bone scintigraphy in bone-only MBC. Materials and Methods This prospective study evaluated participants with bone-only MBC between May 2016 and January 2019 (ClinicalTrials.gov identifier: NCT03266744). Participants were enrolled at initiation of first or subsequent SACT based on standard CT and bone scintigraphy imaging. Baseline whole-body MRI was performed within 2 weeks of entry; those with extraosseous disease were excluded. CT and whole-body MRI were performed every 12 weeks until definitive PD was evident with one or both modalities. In case of PD, bone scintigraphy was used to assess for bone disease progression. Radiologists independently interpreted images from CT, whole-body MRI, or bone scintigraphy and were blinded to results with the other modalities. Systematic differences in performance between modalities were analyzed by using the McNemar test. Results Forty-five participants (mean age, 60 years ± 13 [standard deviation]; all women) were evaluated. Median time on study was 36 weeks (range, 1-120 weeks). Two participants were excluded because of unequivocal evidence of liver metastases at baseline whole-body MRI, two participants were excluded because they had clinical progression before imaging showed PD, and one participant was lost to follow-up. Of the 33 participants with PD at imaging, 67% (22 participants) had PD evident at whole-body MRI only and 33% (11 participants) had PD at CT and whole-body MRI concurrently; none had PD at CT only (P < .001, McNemar test). There was only slight agreement between whole-body MRI and CT (Cohen κ, 0.15). PD at bone scintigraphy was reported in 50% of participants (13 of 26) with bone progression at CT and/or whole-body MRI (P < .001, McNemar test). Conclusion Whole-body MRI enabled identification of progressive disease before CT in most participants with bone-only metastatic breast cancer. Progressive disease at bone scintigraphy was evident in only half of participants with bone progression at whole-body MRI. © RSNA, 2020 Online supplemental material is available for this article.

16.
Proc Natl Acad Sci U S A ; 117(42): 26448-26459, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33020269

RESUMO

Wnt signaling plays a critical role in production and differentiation of neurons and undergoes a progressive reduction during cortical development. However, how Wnt signaling is regulated is not well understood. Here we provide evidence for an indispensable role of neddylation, a ubiquitylation-like protein modification, in inhibiting Wnt/ß-catenin signaling. We show that ß-catenin is neddylated; and inhibiting ß-catenin neddylation increases its nuclear accumulation and Wnt/ß-catenin signaling. To test this hypothesis in vivo, we mutated Nae1, an obligative subunit of the E1 for neddylation in cortical progenitors. The mutation leads to eventual reduction in radial glia progenitors (RGPs). Consequently, the production of intermediate progenitors (IPs) and neurons is reduced, and neuron migration is impaired, resulting in disorganization of the cerebral cortex. These phenotypes are similar to those of ß-catenin gain-of-function mice. Finally, suppressing ß-catenin expression is able to rescue deficits of Nae1 mutant mice. Together, these observations identified a mechanism to regulate Wnt/ß-catenin signaling in cortical development.

17.
Nanoscale ; 12(39): 20250-20257, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33026023

RESUMO

Hydrogen sulfide plays a significant role in living beings, while its abnormal concentration is related to many diseases. Besides, H2S gas is harmful to human beings and the environment. The detection of H2S has therefore attracted much attention in the past several decades. Herein, highly sensitive and selective H2S plasmonic nanoprobes (gold triangular nanoplate core)@(silver shell) (AuTNP@Ag) are reported. By virtue of the high refractive index sensitivity of Au TNPs to the surrounding medium and facile sulfurization of silver by sulfur ions, AuTNP@Ag exhibits great sensitivity to both sulfur ions and H2S gas. The shifts of the plasmon peak are as large as 16 nm for the ventilation of 1 ppm hydrogen sulfide. AuTNP@Ag nanoprobes also exhibit very good sensing linearity at low concentrations of sulfur ions. Moreover, excellent sensing selectivity for sulfur ions is obtained. A type of test gel, which can produce a naked-eye observable color change when exposed to 1-100 ppm hydrogen sulfide gas, is developed using AuTNP@Ag nanoprobes. Owing to the high sensitivity, linearity, and selectivity of the Au TNP@Ag nanoprobes for hydrogen sulfide sensing, this work paves the way for the plasmonic detection of hydrogen sulfide in both biological and environmental applications.

18.
Nanoscale Horiz ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33118586

RESUMO

Correction for 'Nitrogen-doped carbon nanotubes as an anode for a highly robust potassium-ion hybrid capacitor' by Xiuqi Li et al., Nanoscale Horiz., 2020, DOI: 10.1039/d0nh00451k.

19.
J Neurosci ; 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097641

RESUMO

Myosin X (Myo X) transports cargos to the tips of filopodia for cell adhesion, migration, and neuronal axon guidance. Deleted in Colorectal Cancer (DCC) is one of Myo X cargos essential for Netrin-1-regulated axon pathfinding. Myo X's function in axon development in vivo and the underlying mechanisms remain elusive. Here, we provide evidence for Myo X's role in Netrin-1-DCC regulated axon development in developing mouse neocortex. Knocking-out (KO) or knocking-down (KD) Myo X in cortical neurons of embryonic mouse brain impairs axon initiation and contralateral branching/targeting. Similar axon deficits are detected in Netrin-1-KO or DCC-KD cortical neurons. Further proteomic analysis of Myo X binding proteins identifies KIF13B (a kinesin family motor protein). Myo X interaction with KIF13B is induced by Netrin-1. Netrin-1 promotes anterograde transportation of Myo X into axons in KIF13B dependent manner. KIF13B-KD cortical neurons exhibit similar axon deficits. Together, these results reveal Myo X-KIF13B as a critical pathway for Netrin-1 promoted axon initiation and branching/targeting.SIGNIFICANCE STATEMENTNetrin-1 increases Myo X interaction with KIF13B, and thus promotes axonal delivery of Myo X and axon initiation and contralateral branching in developing cerebral neurons, revealing unrecognized functions and mechanisms underlying Netrin-1 regulation of axon development.

20.
Huan Jing Ke Xue ; 41(10): 4382-4391, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124370

RESUMO

Based on the online monitoring data of gaseous pollutants and components in PM2.5 from Chengdu super observatory of atmospheric environment, the meteorological factors and component characteristics of three haze pollution process in Chengdu from 2019 to 2020 were analyzed. The CMB model was adopted to simulate the sources and variation trends of PM2.5 pollution during the study period, and the causes of each pollution process were analyzed. The results showed that all the three pollution processes occurred under adverse meteorological conditions, where the relative humidity and temperature continued to rise and the wind speed and boundary layer height continued to decrease. The average daily relative humidity was greater than 70%, average daily temperature was greater than 8℃, average daily wind speed was less than 0.8 m ·s-1, and average daily boundary layer height was less than 650 m. During the three events of pollution, the main components were NO3-, OC, NH4+, and SO42-. Among them, the mass concentration and proportion of NO3- increased by 1.47-2.09 and 0.22-0.35 times, respectively, during the pollution period as compared to those during the clean period. NO3- was a key component of PM2.5 pollution during winter in Chengdu. During the three pollution processes, the mean values of SOR and NOR were 0.40 and 0.27, respectively, and the secondary transformation degree of SO2 and NOx was high. The conversion of SO2 to SO42- was mainly dominated by heterogeneous oxidation at night, and the conversion of NOx to NO3- was dominated by heterogeneous hydrolysis. The characteristics of the three processes were slightly different. Process Ⅰ showed evident secondary nitrate-dominated characteristics. During the period of rising PM2.5 concentration in process Ⅱ, it was mainly affected by coal emissions, but during the periods of high PM2.5 concentration, it was mainly affected by NO3-. Process Ⅲ was also a nitrate-dominated process, but emissions of fossil fuel combustion had increased during certain polluted periods. Secondary nitrate, secondary sulfate, motor vehicles, and coal combustion were the main pollution sources during the study period. The PM2.5 concentration was positively correlated with the contribution of secondary nitrate and negatively correlated with the contribution of dust source.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
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