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1.
Nanotechnology ; 32(1): 015708, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32937609

RESUMO

In this paper, we used tannic acid (TA) functionalized carbon nanotubes (TCNTs), and silver nanowires (AgNWs) to construct a new type of transparent conductive film (TCF) with a double-layered conductive network structure. The hybrid film exhibits excellent light transmittance, high electrical conductivity, ultra-flexibility, and strong adhesion. These outstanding performances benefit from the filling and adhesion of hydrophilic TCNT layers to the AgNW networks. Besides, we introduced the post-treatment process of mechanical pressing and covering polymer conductive polymer PEDOT:PSS, which obtained three layers of TCNT/AgNW/PEDOT hybrid film and greatly improved the comprehensive properties. The hybrid film can reach a sheet resistance of 9.2 Ω sq-1 with a transmittance of 83.4% at 550 nm wavelength, and a low root mean square (RMS) roughness (approximately 3.8 nm). After 10 000 bends and tape testing, the conductivity and transmittance of the hybrid film remain stable. The resistance of the film has no significant degradation after 14 d of exposure to high temperature of 85 °C and humidity of 85%, indicating excellent stability. The organic light-emitting diodes (OLEDs) with TCNT/AgNW/PEDOT hybrid film as anode exhibit high current density and luminosity, confirming this process has considerable potential application in photovoltaic devices.

2.
Talanta ; 221: 121451, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33076074

RESUMO

In this paper, a rationally designed aptasensing platform based on Hybridization Chain Reaction (HCR) and G-quadruplex DNAzyme for the fluorescence detection of Carcinoembryonic Antigen (CEA) has been developed. In the presence of target CEA, the aptamer sequence in Aptamer Probe (AP) specifically bound to CEA, resulting in the AP conformation change and thus releasing initiator, which triggered the autonomous cross-opening of Hairpin 1 (H1) and Hairpin 2 (H2) that yielded extended nicked double-stranded DNA via HCR. Upon the addition of hemin, G-rich segments at the end of H1 and H2 self-assembled into the peroxidase-mimicking hemin/G-quadruplex DNAzymes, which catalyzed the hydrogen peroxide-mediated oxidation of thiamine to achieve fluorescence detection of CEA. The HCR product, and the formation and catalytic performance of DNAzyme were characterized by agarose gel electrophoresis, UV-vis spectroscopy and fluorescence spectroscopy, respectively. Under optimal conditions, the fluorescent aptasensor showed a linear relationship ranging from 0.25 to 1.5 nM toward CEA with a detection limit of 0.2 nM. In addition, this aptasensor exhibited high selectivity for CEA without being affected by other interfering proteins, such as IgG, AFP and PSA. Furthermore, this proposed aptasensor was successfully applied to CEA analysis in diluted human serum samples. It is believed that this strategy has a promising potential in biochemical analysis and clinic application.

3.
PLoS Genet ; 16(10): e1009070, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33064773

RESUMO

The major glycerophospholipid phosphatidylethanolamine (PE) in the nervous system is essential for neural development and function. There are two major PE synthesis pathways, the CDP-ethanolamine pathway in the endoplasmic reticulum (ER) and the phosphatidylserine decarboxylase (PSD) pathway in mitochondria. However, the role played by mitochondrial PE synthesis in maintaining cellular PE homeostasis is unknown. Here, we show that Drosophila pect (phosphoethanolamine cytidylyltransferase) mutants lacking the CDP-ethanolamine pathway, exhibited alterations in phospholipid composition, defective phototransduction, and retinal degeneration. Induction of the PSD pathway fully restored levels and composition of cellular PE, thus rescued the retinal degeneration and defective visual responses in pect mutants. Disrupting lipid exchange between mitochondria and ER blocked the ability of PSD to rescue pect mutant phenotypes. These findings provide direct evidence that the synthesis of PE in mitochondria contributes to cellular PE homeostasis, and suggest the induction of mitochondrial PE synthesis as a promising therapeutic approach for disorders associated with PE deficiency.

4.
Plants (Basel) ; 9(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33065969

RESUMO

Nucleotide-binding site and leucine-rich repeat (NBS-LRR) genes represent the most important disease resistance genes in plants. The genome sequence of kiwifruit (Actinidia chinensis) provides resources for the characterization of NBS-LRR genes and identification of new R-genes in kiwifruit. In the present study, we identified 100 NBS-LRR genes in the kiwifruit genome and they were grouped into six distinct classes based on their domain architecture. Of the 100 genes, 79 are truncated non-regular NBS-LRR genes. Except for 37 NBS-LRR genes with no location information, the remaining 63 genes are distributed unevenly across 18 kiwifruit chromosomes and 38.01% of them are present in clusters. Seventeen families of cis-acting elements were identified in the promoters of the NBS-LRR genes, including AP2, NAC, ERF and MYB. Pseudomonas syringae pv. actinidiae (pathogen of the kiwifruit bacterial canker) infection induced differential expressions of 16 detected NBS-LRR genes and three of them are involved in plant immunity responses. Our study provides insight of the NBS-LRR genes in kiwifruit and a resource for the identification of new R-genes in the fruit.

5.
J Neurointerv Surg ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067258

RESUMO

BACKGROUND: Drug-coated balloon (DCB) is a potential treatment for patients with low restenosis risk in vertebral artery origin stenosis (VAOS). However, the clinical data of long-term outcome are limited. OBJECTIVE: To evaluate the safety and efficacy of a DCB in patients with severe VAOS. METHODS: A prospective, non-randomized, single-center pilot study enrolled 30 patients with severe VAOS treated with DCB between 2017 and 2018. The first 20 patients were treated with a balloon-to-vessel ratio of predilation (pBVR)<0.8 (small-size balloon predilation) and the following 10 patients were treated with a pBVR 0.8-1.0 (large-size balloon predilation). Primary safety endpoints included 30-day death, stroke, and transient ischemic attack (TIA). The main efficacy outcome was restenosis at 6 months, defined as a peak systolic velocity >140 cm/s measured by Doppler ultrasound. Long-term outcomes, including TIAs, stroke, death, and modified Rankin Scale score, were followed up to 2 years. RESULTS: Technical success (<50% residual stenosis) was achieved in 26 patients (mean age 66.2±7.0; seven women). Four patients received bailout stenting and were excluded. Ultrasound confirmed restenosis at 6 months in 10 (38.5%) of 26, which was significantly less frequent in LSBP (LSBP vs SSBP=10% vs 56.3%, p<0.05). No adverse events occurred within 30 days of treatment. 19 patients were followed up for 2 years, with two deaths due to cancer. CONCLUSION: This pilot study suggests that DCB is a safe approach for VAOS. The relatively low restenosis rate indicates the its potential long-term efficacy for VAOS. Future randomized controlled trials to confirm its efficacy are warranted.

7.
Environ Sci Technol ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33054212

RESUMO

The mechanisms by which lime and/or phosphate addition impacts the preservation of soil organic matter (OM) are poorly understood. We explored the changes in quantity and chemistry of water-extractable organic matter (WEOM) in the bulk soil and its heavy density fraction (>1.6 g/cm3) of an unmanaged C-rich volcanic soil caused by lime and/or phosphate application. The addition of lime or phosphate caused (i) a significant increase in the WEOM, along with a decrease in its C/N ratio and an increase in its aromaticity, and (ii) changes in the WEOM chemical composition, measured with pyrolysis-gas chromatography/mass spectrometry, this being most impacted by lime application. The combined effect of lime and phosphate addition on the quantity and chemistry of WEOM was larger than the effects of separate lime and phosphate additions. By comparing the response of the bulk soil and the heavy fraction, we infer that phosphate has a greater contribution to the destabilization of vulnerable particulate OM, while lime causes a comparable disruption in the particulate OM and that in the heavy fraction. These findings provide a mechanistic insight into the decreased OM stability after liming and/or P fertilizing Andosols. They have implications for designing climate-smart management practices for these soils.

8.
Nano Lett ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33054225

RESUMO

Optical wavefront engineering has been rapidly developing in fundamentals from phase accumulation in the optical path to the electromagnetic resonances of confined nanomodes in optical metasurfaces. However, the amplitude modulation of light has limited approaches that usually originate from the ohmic loss and absorptive dissipation of materials. Here, an atomically thin photon-sieve platform made of MoS2 multilayers is demonstrated for high-quality optical nanodevices, assisted fundamentally by strong excitonic resonances at the band-nesting region of MoS2. The atomic thin MoS2 significantly facilitates high transmission of the sieved photons and high-fidelity nanofabrication. A proof-of-concept two-dimensional (2D) nanosieve hologram exhibits 10-fold enhanced efficiency compared with its non-2D counterparts. Furthermore, a supercritical 2D lens with its focal spot breaking diffraction limit is developed to exhibit experimentally far-field label-free aberrationless imaging with a resolution of ∼0.44λ at λ = 450 nm in air. This transition-metal-dichalcogenide (TMDC) photonic platform opens new opportunities toward future 2D meta-optics and nanophotonics.

9.
Nanotechnology ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059341

RESUMO

Graphene and its derivatives have shown fascinating potential in biomedical applications. However, the biocompatibility of graphene with vascular smooth muscle cells (VSMCs) and applications to vascular engineering have not been explored extensively. Using a rat aortic smooth muscle cell line, A7r5, as a VSMC model, we have explored the effects of graphene oxide (GO) on the growth and behaviours of VSMCs. Results demonstrated that GO had no obvious toxicity to VSMCs. Cells cultured on GO retained the expression of smooth muscle cell-specific markers CNN1, ACTA2 and SMTN, on both mRNA and protein levels. A wound healing assay demonstrated no effect of GO on cell migration. We also found that small-flaked GO favoured the proliferation of VSMCs, suggesting a potential of using surface chemistry or physical properties of GO to influence cell growth behaviour. These results provide insight into the suitability of GO as a scaffold for vascular tissue engineering.

10.
Chem Commun (Camb) ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063062

RESUMO

Lithium-oxygen batteries (LOBs) can suffer from large charge overpotentials during the sluggish oxygen evolution reaction (OER). Here, a strategy used in the photo-electrochemical (PEC) water oxidation area is integrated into hybrid LOBs. Coating α-Fe2O3 with NiOOH results in enhanced electrochemical properties, and the as-assembled hybrid LOBs deliver a low charge voltage of 3.03 V, high energy efficiency of 88%, and long-term stability for over 350 hours.

11.
BMC Gastroenterol ; 20(1): 323, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008291

RESUMO

BACKGROUND: Foreign body ingestion is a common clinical problem. The upper esophagus is the most common site of foreign body, accounting for more than 75% of all cases, but cases with a foreign body in the duodenal papilla or common bile duct are rarely reported. CASE PRESENTATION: Herein, we report a rare case that a patient's abdominal pain resembling gastric ulcer was caused by a 3 cm long fishbone inserted into the duodenal papilla. CONCLUSION: Fishbone inserted into the duodenal papilla can cause an abdominal pain resembling gastric ulcer. Endoscopy is useful for the diagnosis and treatment of fishbone ingestion in clinical.

12.
Nat Cell Biol ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020597

RESUMO

PIWI-interacting RNAs (piRNAs) are abundantly expressed during cardiac hypertrophy. However, their functions and molecular mechanisms remain unknown. Here, we identified a cardiac-hypertrophy-associated piRNA (CHAPIR) that promotes pathological hypertrophy and cardiac remodelling by targeting METTL3-mediated N6-methyladenosine (m6A) methylation of Parp10 mRNA transcripts. CHAPIR deletion markedly attenuates cardiac hypertrophy and restores heart function, while administration of a CHAPIR mimic enhances the pathological hypertrophic response in pressure-overloaded mice. Mechanistically, CHAPIR-PIWIL4 complexes directly interact with METTL3 and block the m6A methylation of Parp10 mRNA transcripts, which upregulates PARP10 expression. The CHAPIR-dependent increase in PARP10 promotes the mono-ADP-ribosylation of GSK3ß and inhibits its kinase activity, which results in the accumulation of nuclear NFATC4 and the progression of pathological hypertrophy. Hence, our findings reveal that a piRNA-mediated RNA epigenetic mechanism is involved in the regulation of cardiac hypertrophy and that the CHAPIR-METTL3-PARP10-NFATC4 signalling axis could be therapeutically targeted for treating pathological hypertrophy and maladaptive cardiac remodelling.

13.
Respir Med ; 173: 106159, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33010731

RESUMO

BACKGROUND: The outbreak of COVID-19 caused by SARS-CoV-2 has been a pandemic. The objective of our study was to explore the association between sex and clinical outcomes in patients with COVID-19. METHODS: Detailed clinical data including clinical characteristics, laboratory tests, imaging features and treatments of 1190 cases of adult patients with confirmed COVID-19 were retrospectively analyzed. Associations between sex and clinical outcomes were identified by multivariable Cox regression analysis. RESULTS: There were 635 (53.4%) male and 555 (46.6%) female patients in this study. Higher rates of acute kidney injury (5.5% vs. 2.9%, p = 0.026), acute cardiac injury (9.1% vs. 4.3%, p = 0.001), and disseminated intravascular coagulation (2.5% vs. 0.7%, P = 0.024) were observed in males. Compared with female patients, male patients with COVID-19 had a higher inhospital mortality rate (15.7% vs. 10.3%, p = 0.005). However, Cox regression analysis showed that sex did not influence inhospital mortality of COVID-19 patients. CONCLUSIONS: Male sex was associated with a worse prognosis of COVID-19, but it seems not to be an independent prognostic factor.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33046243

RESUMO

Acidithiobacillus ferrooxidans ATCC23270 is a gram-negative and autotrophic bacillus acquiring energy via the oxidation of iron and sulfur. The pet II operon is involved in the sulfur metabolism of A. ferrooxidans. However, the mechanisms that control the expression of the pet II operon are poorly understood. We previously described that the AFE2726 protein is associated with the expression of the pet II operon. Here, we attempted to analyze the involvement of AFE2726 in the regulation of pet II operon expression. First, pEGF recombinant vectors driven by the promotor of the pet II operon, denoted pEGF-pet II, were constructed. Then, DH5α E. coli cultures containing the vector mentioned above were cultivated in Na2S2O3, as this medium substantially enhances the expression of green fluorescent proteins. To examine the regulatory effect of AFE2726 on the pet II operon, the C62/V and C72/V mutants for AFE2726 were constructed in pEGF-pet II vectors using the site-directed deletion method. Compared to pEFG-pet II and pEFG-pet II-Δ-C62/V, pEFG-pet II-Δ-C72/V reduced the expression of green fluorescent proteins dramatically when transformed into DH5α E.coli in Na2S2O3 medium. This suggested that the 72nd cysteine was a crucial residue of the AFE2726 protein, affecting the response of the pet II operon to sodium thiosulfate. Furthermore, the binding site of AFE2726 on the promotor of the pet II operon was identified using the electrophoretic mobility shift assay (EMSA), and it was found to be a 34bp inverted repeat sequence (named IR4), which ranged from -65 to -32. In summary, our results indicated that the AFE2726 protein regulates the pet II operon by binding to the IR4 sequence in its promotor region, whose function is likely affected by Na2S2O3 binding to its Cys72 residue counterpart.

15.
BMC Genomics ; 21(1): 700, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028208

RESUMO

BACKGROUND: A high-density genetic linkage map is essential for QTL fine mapping, comparative genome analysis, identification of candidate genes and marker-assisted selection in aquaculture species. Pelteobagrus vachelli is a very popular commercial species in Asia. However, some specific characters hindered achievement of the traditional selective breeding based on phenotypes, such as lack of large-scale genomic resource and short of markers tightly associated with growth, sex determination and hypoxia tolerance related traits. RESULTS: By making use of 5059 ddRAD markers in P. vachelli, a high-resolution genetic linkage map was successfully constructed. The map' length was 4047.01 cM by using an interval of 0.11 cm, which is an average marker standard. Comparative genome mapping revealed that a high proportion (83.2%) of markers with a one-to-one correspondence were observed between P. vachelli and P. fulvidraco. Based on the genetic map, 8 significant genome-wide QTLs for 4 weight, 1 body proportion, 2 sex determination, and 1 hypoxia tolerance related traits were detected on 4 LGs. Some SNPs from these significant genome-wide QTLs were observably associated with these phenotypic traits in other individuals by Kompetitive Allele Specific PCR. In addition, two candidate genes for weight, Sipa1 and HSD11B2, were differentially expressed between fast-, medium- and slow-growing P. vachelli. Sema7a, associated with hypoxia tolerance, was induced after hypoxia exposure and reoxygenation. CONCLUSIONS: We mapped a set of suggestive and significant QTLs as well as candidate genes for 12 growth, 1 sex determination and 1 hypoxia tolerance related traits based on a high-density genetic linkage map by making use of SNP markers for P. fulvidraco. Our results have offered a valuable method about the much more efficient production of all-male, fast growth and hypoxia tolerance P. vachelli for the aquaculture industry.

16.
Curr Med Chem ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33050856

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, with nearly one million new cases and deaths every year. Owing to the complex pathogenesis, hidden early symptoms, rapidly developing processes and poor prognosis, the morbidity and mortality of HCC are increasing yearly. With the progress being made in modern medicine, the treatment of HCC is no longer limited to traditional methods. Targeted therapy and immunotherapy have emerged to treat advanced and metastatic HCC in recent years. Since Sorafenib is the first molecular targeting drug against angiogenesis, targeted drugs for HCC are continually emerging. Moreover, immunotherapy plays a vital role in clinical trials. In particular, the application of immune checkpoint inhibitors, which have received increasing attention in the field of cancer treatment, is a possible research path. Interestingly, these two therapies generally complement each other at some stages of HCC, bringing new hope for patients with advanced HCC. In this paper, we discuss the research progress of targeted therapy and immunotherapy for HCC in recent years, which will provide a reference for the further development of drugs for HCC.

17.
JAMA Dermatol ; 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33052383
18.
Eur Radiol ; 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33052465

RESUMO

OBJECTIVES: This study sought to validate the performance of simultaneous non-contrast angiography and intraplaque hemorrhage (SNAP) imaging in characterizing carotid IPH by histology. METHODS: Thirty-five patients with carotid atherosclerotic disease (symptomatic 50-70% stenosis or > 70% stenosis) scheduled for carotid endarterectomy underwent 3.0-T carotid MR imaging by acquiring SNAP and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) sequences. Presence and area of IPH were separately evaluated on SNAP and MP-RAGE images. Presence and area of IPH were also assessed on histology. Agreement between SNAP/MP-RAGE and histology was determined in identify and quantify IPH using Cohen kappa, Spearman correlation, and Bland-Altman analyses. RESULTS: Of all 35 patients (mean age: 63.1 ± 8.8 years; 27 males), 128 slices with successful registration were eligible for analysis. The accuracy, sensitivity, specificity, and positive and negative predictive values were 86.7%, 85%, 89.6%, 93.2%, and 78.2% for SNAP, and 76.6%, 75%, 79.2%, 85.7%, and 65.5% for MP-RAGE in identification of IPH, respectively. In identification of IPH, the kappa value between SNAP and histology and between MP-RAGE and histology was 0.725 and 0.520, respectively. The correlation between SNAP and histology (r = 0.805, p < 0.001) was stronger than that between MP-RAGE and histology (r = 0.637, p < 0.001) in measuring IPH area. Bland-Altman analysis showed that, in measuring IPH area, the bias of SNAP (1.4 mm2, 95% CI: - 0.016 to 2.883) was smaller than that of MP-RAGE (1.7 mm2, 95% CI: - 0.039 to 3.430) compared with histology. CONCLUSIONS: This validation study by histology demonstrates that SNAP sequence better identifies and quantifies carotid intraplaque hemorrhage compared with traditional MP-RAGE sequence. KEY POINTS: • SNAP imaging showed better agreement with histology compared with MP-RAGE imaging, especially for the IPHs with small size. • SNAP sequence is a more effective tool to identify and quantify carotid IPH than traditional sequence of MP-RAGE that can help clinicians to optimizing the treatment strategy. • The plaque components of rich lipid pools or loose matrix and chronic/old IPH (cholesterol crystals) can lead to false positive and false negative results in SNAP and MP-RAGE imaging for identifying IPH.

19.
PLoS Negl Trop Dis ; 14(10): e0008720, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001992

RESUMO

The parasitic mite Sarcoptes scabiei is an economically highly significant parasite of the skin of humans and animals worldwide. In humans, this mite causes a neglected tropical disease (NTD), called scabies. This disease results in major morbidity, disability, stigma and poverty globally and is often associated with secondary bacterial infections. Currently, anti-scabies treatments are not sufficiently effective, resistance to them is emerging and no vaccine is available. Here, we report the first high-quality genome and transcriptomic data for S. scabiei. The genome is 56.6 Mb in size, has a a repeat content of 10.6% and codes for 9,174 proteins. We explored key molecules involved in development, reproduction, host-parasite interactions, immunity and disease. The enhanced 'omic data sets for S. scabiei represent comprehensive and critical resources for genetic, functional genomic, metabolomic, phylogenetic, ecological and/or epidemiological investigations, and will underpin the design and development of new treatments, vaccines and/or diagnostic tests.

20.
Chem Asian J ; 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33089926

RESUMO

In this work, a series of gold-supported titanium oxide composites have been prepared and high selectivity (over 90%) of hydrogen peroxide is achieved. For the first time, electrochemical impedance spectroscopy and electron spin resonance analysis demonstrate that high charge transfer impedance of the catalyst can suppress the decomposition of OOH* intermediates thus promoting the two-electron process of the oxygen reduction reaction.

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