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1.
Biol Direct ; 17(1): 1, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991683

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) have been reported to be vital factors to affect the expression of genes and proteins. Also, it has been proved that the abnormal expression or mutation of lncRNAs stands as a signal of metastasis and proliferation of cancer. Nevertheless, the majority of lncRNAs still need to be explored in abundant cancers especially in oral squamous cell carcinoma (OSCC). METHODS: RT-qPCR assays were applied to test the expression of RNAs. Mechanism assays were performed to verify the combination among NORAD, TPM4 and miR-577. Also, functional assays were conducted to verify the function of RNAs on OSCC cells. RESULTS: LncRNA NORAD was highly expressed in OSCC tissues and cells. NORAD silencing repressed the biological behaviors of OSCC cells. MiR-577 was found in OSCC with low expression, and RIP assays illustrated that NORAD, miR-577 and TPM4 coexisted in RNA-induced silencing complexes. Rescue assays proved that the overexpression of TPM4 could recover the effect of NORAD silencing on OSCC progression. CONCLUSIONS: It was revealed that NORAD functioned as a tumor promoter to sponge miR-577 thus elevating TPM4 in OSCC, which indicated that NORAD was worthy to be studied as a target for the treatment of OSCC.

2.
J Hazard Mater ; 423(Pt A): 127078, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523496

RESUMO

Beibu Gulf is an important shellfish aquaculture area in the northwest of the South China Sea, China. In this study, the toxin profile and spatial-temporal distribution of domoic acid (DA) and 10 lipophilic phycotoxins were systematically analyzed in the bivalve mollusks collected in Beibu Gulf from October 2018 to October 2020. Neurotoxin DA was first detected in the mollusks from the investigative regions with a prevalence of 17.7%, peaking at 401 µg kg-1. Cyclic imines (CIs) including gymnodimine-A (GYM-A, 46.6%) and 13-desmethyl-spirolide-C (SPX1, 15.8%) predominated the lipophilic phycotoxins in shellfish, peaking at 10.1 µg kg-1 and 19.6 µg kg-1, respectively. Gymnodimine-A partially accompanied by SPX1 was detected in all batches of shellfish samples, suggesting that Alexandrium ostenfeldii and Karenia selliformis were possible sources of CIs-group toxins in Beibu Gulf. During the investigative period, relatively higher levels of DA occurred in shellfishes from March to August, while slightly higher contents of CIs in mollusks appeared in October and December. Spatial distribution of the targeted phycotoxins demonstrated that shellfishes tended to accumulate relatively higher contents of toxins in Lianzhou, Qinzhou and Tieshan bays.


Assuntos
Bivalves , Toxinas Marinhas , Animais , China , Iminas , Ácido Caínico/análogos & derivados , Prevalência
3.
J Colloid Interface Sci ; 606(Pt 2): 1111-1119, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34487931

RESUMO

Lithium-sulfur (Li-S) batteries are considered to be promising candidates for next-generation storage systems. However, the practical applications are still hindered by the severe capacity decay, mainly caused by the large volume change, polysulfide shuttle and sluggish sulfur conversion kinetics. Herein, hollow urchin-like Mn3O4 (HU-Mn3O4) microspheres as sulfur hosts have been synthesized by the hydrothermal method and calcination treatment, aiming to prevent the polysulfide dissolution (benefiting from the strong polysulfide anchoring effect of Mn3O4) and alleviate the volume expansion of sulfur (benefiting from the special hollow structure). Meanwhile, the urchin-like thorny surface also facilitates the rapid ion/electron transfer and the abundant active sites for the fast sulfur redox kinetics. When used as the sulfur host in Li-S batteries, the S@HU-Mn3O4 cathode delivers a high initial capacity of 1137.4 mAh g-1 with a slow capacity decay of 0.042% after 200 cycles at 0.2 C. Even under the conditions of lean electrolyte (E/S = 7 mL g-1) and low N/P ratio (N/P = 2.1), the S@HU-Mn3O4 cathode still enables a stable cycling performance with a high gravimetric energy density (202 Wh kg cell-1), demonstrating its great potential in the development of future practical Li-S battery materials.

4.
Front Plant Sci ; 12: 756433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868150

RESUMO

The quality of tea product and the metabolism of quality-related compounds in young shoots are significantly affected by the nitrogen(N) supply. However, little is known of the metabolic changes that take place in tea roots and mature leaves under different supplies, which has a large effect on the accumulation of quality-related compounds in young shoots. In this study, young shoots, mature leaves, and roots under different N conditions were subjected to metabolite profiling using gas chromatography and ultraperformance liquid chromatography, coupled with quadrupole time-of-flight mass spectrometry. The contents of free amino acids (e.g., theanine and glutamate) involved in N metabolism were significantly greater under high N than under low N, while a high N supply reduced soluble sugars (e.g., glucose) in all three tissues. Organic acids (e.g., malate, fumarate, α-ketoglutatare, and succinate) involved in tricarboxylic acid cycle remarkably increased as the nitrogen supply increased, which confirms that carbon (C) allocation was restricted by increasing the nitrogen supply, especially in mature leaves. RT-PCR results indicated that gene expression related to nitrogen assimilation significantly increased in roots with increasing nitrogen supply, which had a significant positive relationship with the level of free amino acids in young shoots. In addition, the expression of most genes involved in flavonoid synthesis was significantly upregulated under conditions of low nitrogen supply relative to high nitrogen supply in young shoot and roots. These data suggest that enhanced assimilation of N in tea roots and the coordinated regulation of C (sugars, organic acids, and flavonoids) and N(amino acids) in mature leaves can lead to a high accumulation of amino acids in young shoots. Furthermore, as the N supply increased, more C was partitioned into compounds containing N in mature leaves and roots, resulting in a decrease in flavonoids in young shoots. In conclusion, the accumulation of amino acids and flavonoids in young tea shoots is highly correlated with carbon and nitrogen metabolism in roots and mature leaves.

5.
Sci Total Environ ; 812: 152593, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34953837

RESUMO

To clarify the spatial patterns of disease burden caused by toxic metals in fine particulate matter (PM2.5) across China, annual concentration levels of typical toxic metals in PM2.5 over 60 cities of China were retrieved. Then, potential years of life lost (PYLL) attributable to toxic metal (As, Cd, Cr (VI), Mn, and Ni) exposure was calculated from health risk assessments and lifetable estimates. The results show that Cr(VI) and As were the most polluted metals and greatly exceeded the recommended annual values in the National Ambient Air Quality Standard of China. PYLL for each death (mean ± standard deviation) of 19.8 ± 4.5 years was observed for lung cancer, followed closely by COPD and pneumonia. Furthermore, the PYLL rate (years per 100,000 people) attributable to exposure to these toxic metals was 457 (male: 505, female: 402) years for different cities; therein, Cr(VI) contributed the highest PYLL among these toxic metals, with a proportion of 72.7% (male: 75.3%, female: 69.5%), followed by As of 16.4% (male: 13.8%, female: 19.8%). The concentration level and PYLL both showed large spatial variability, of which the top-ranking cities were observed to be affected by well-developed metal-related industries and coal-powered industrial sectors.

6.
Pathogens ; 10(11)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34832545

RESUMO

Tolypocladium, a diverse genus of fungicolous fungi belonging to Ophiocordycipitaceae, includes saprotrophic soil inhabitants, plant endophytes and pathogens of insects, nematodes, rotifers, and parasites of truffle-like fungi. Here, we review the research progress achieved for Tolypocladium regarding its taxonomy, species diversity, geographic distribution, host affiliations and ecological diversity. Furthermore, an undescribed taxon from China was established using morphology and multi-gene phylogeny. Tolypocladium inusitaticapitatum is introduced as a new species parasitizing ectomycorrhizal Elaphomyces species. It is diagnosed by its irregularly enlarged fertile heads and lemon, yellow-to-dark-brown, smooth and nearly cylindrical stipe. Phylogenetic analyses based on SSU, LSU, ITS, TEF1-α and RPB2 sequence data showed T. inusitaticapitatum to be an independent lineage separated from T. flavonigrum in the clade comprising T. capitatum, T. fractum and T. longisegmentatum. A key for identifying the sexual Tolypocladium species is also provided.

8.
Mitochondrial DNA B Resour ; 6(12): 3369-3371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805514

RESUMO

The plastid genome of the deep-shade plant Selaginella erythropus, which has highly unusual chloroplasts, was characterized using Illumina pair-end sequencing. This plastome is 140,151 bp in length with a large single-copy region (LSC) of 56,133 bp, a small single-copy region (SSC) of 61,268 bp, and two direct repeats (DRs) of 11,375 bp. The overall GC content is 50.68%, while those of LSC, SSC, and DR are 48.96%, 50.3%, and 55.96%, respectively. The plastome contains 102 genes, including 76 protein-coding, 15 tRNA (12 tRNA species), and 8 rRNA genes (4 rRNA species). The phylogenetic analysis shows that S. erythropus is closely related to S. moellendorffii and S. doederleinii. This result is consistent with the previous phylogenetic relationship inferred from multiple plastid and nuclear loci. However, only S. erythropus has the two-zoned giant chloroplast, the bizonoplast. The plastome provides an excellent reference for understanding the unique chloroplast differentiation in Selaginellaceae.

9.
Nano Lett ; 21(23): 9976-9982, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34813332

RESUMO

Electrochromic devices have attracted considerable interest for smart windows. However, current development suffers from the requirement of the external power sources and rigid ITO substrate, which not only causes additional energy consumption but also limits their applications in flexible devices. Inspired by galvanic cell, we demonstrate a self-powered flexible electrochromic device by integrating Ag/W18O49 nanowire film with the Al sheet. The Ag nanowire film first acted as the electrode to replace the ITO substrate, then coupled with the Al sheet to induce an open-circuit voltage of ∼0.83 V, which is high enough to drive the coloration of W18O49 nanowires. Remarkably, the flexible self-powered electrochromic device only expends ∼6.8 mg/cm2 of the Al sheet after 450 electrochromic switching cycles and the size can be easily expanded with an area of 20 × 20 cm2, offering significant potential applications for the next generation of flexible electrochromic smart window.

10.
World J Stem Cells ; 13(9): 1278-1292, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34630862

RESUMO

Brain diseases, including brain tumors, neurodegenerative disorders, cerebrovascular diseases, and traumatic brain injuries, are among the major disorders influencing human health, currently with no effective therapy. Due to the low regeneration capacity of neurons, insufficient secretion of neurotrophic factors, and the aggravation of ischemia and hypoxia after nerve injury, irreversible loss of functional neurons and nerve tissue damage occurs. This damage is difficult to repair and regenerate the central nervous system after injury. Neural stem cells (NSCs) are pluripotent stem cells that only exist in the central nervous system. They have good self-renewal potential and ability to differentiate into neurons, astrocytes, and oligodendrocytes and improve the cellular microenvironment. NSC transplantation approaches have been made for various neurodegenerative disorders based on their regenerative potential. This review summarizes and discusses the characteristics of NSCs, and the advantages and effects of NSCs in the treatment of brain diseases and limitations of NSC transplantation that need to be addressed for the treatment of brain diseases in the future.

11.
Cancer Med ; 10(23): 8507-8517, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34658153

RESUMO

PURPOSE: To explore the differences between prolonged continuous Pringle maneuver (CPM) and prolonged intermittent Pringle maneuver (IPM) in patients with hepatocellular carcinoma (HCC), who underwent complex hepatectomy. METHODS: This retrospective cohort study performed between June 2014 and May 2016 included 142 patients who underwent complex hepatectomy for HCC and concomitant chronic liver disease but with good liver function. Patients were categorized into CPM (n = 69) and IPM groups (n = 73). The differences in these aspects were compared between the two groups which include operation time, intraoperative bleeding, perioperative transfusion, postoperative complications, liver function injury, postoperative overall survival (OS), and tumor recurrence. RESULTS: The cumulative clamping time, operation time, intraoperative bleeding, and perioperative transfusion rates were 38.0, 132 min, 300 ml, and 17.4% in CPM and 40.0, 145 min, 400 ml, and 32.9% in IPM, respectively. There were significant intergroup differences in operation time (p = 0.018), intraoperative bleeding (p < 0.001), and perioperative transfusion rates (p = 0.034). Besides, the postoperative complications and postoperative liver function injury of the CPM group were better than those of IPM. There was no significant intergroup difference in OS (p = 0.908) and tumor recurrence (p = 0.671) between two groups. CONCLUSION: Compared with IPM, CPM with a cumulative clamping time between 30 and 50 min can shorten operation time, reduce intraoperative bleeding and perioperative transfusion, and reduce postoperative complications and postoperative liver function injury in patients who underwent complex hepatectomy for HCC and concomitant liver disease but with good liver function. There was no significant difference in OS and tumor recurrence between two groups.

12.
Natl Sci Rev ; 8(4): nwaa179, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34691611

RESUMO

The human retina is a complex neural tissue that detects light and sends visual information to the brain. However, the molecular and cellular processes that underlie aging primate retina remain unclear. Here, we provide a comprehensive transcriptomic atlas based on 119 520 single cells of the foveal and peripheral retina of humans and macaques covering different ages. The molecular features of retinal cells differed between the two species, suggesting distinct regional and species specializations of the human and macaque retinae. In addition, human retinal aging occurred in a region- and cell-type-specific manner. Aging of human retina exhibited a foveal to peripheral gradient. MYO9A- rods and a horizontal cell subtype were greatly reduced in aging retina, indicating their vulnerability to aging. Moreover, we generated a dataset showing the cell-type- and region-specific gene expression associated with 55 types of human retinal disease, which provides a foundation to understanding of the molecular and cellular mechanisms underlying human retinal diseases. Such datasets are valuable to understanding of the molecular characteristics of primate retina, as well as molecular regulation of aging progression and related diseases.

13.
Nano Lett ; 21(21): 9203-9209, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34677062

RESUMO

Assembling various nanowires together, enabling the assemblies with tailored optical, electrical, and multifunctional properties, represents a promising technology for next generation multifunctional electronics. Here we demonstrate a novel multicolor electrochromic device by coassembling W18O49 and V2O5 nanowires using solution-based Langmuir-Blodgett technique. The transparent W18O49 nanowire film became orange with the increasing addition of V2O5 nanowires and the film underwent a dynamic color change (orange, green, and gray) on application of different electrochemical biases of 2, 0, and -0.5 V (vs Ag/AgCl). Both the transmittance and color of the device can be easily controlled by manipulating the layers of coassembled nanowires and the ratios between the two nanowires. On the basis of this approach, different patterns can be easily fabricated with the addition of corresponding masks, and the solid electrochromic device is assembled, suggesting its significant potentials in smart windows and multicolor electrochromic displays.

14.
J Am Chem Soc ; 143(43): 17910-17914, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34677969

RESUMO

Herein, a single biomolecule is imaged by electrochemiluminescence (ECL) using Ru(bpy)32+-doped silica/Au nanoparticles (RuDSNs/AuNPs) as the ECL nanoemitters. The ECL emission is confined to the local surface of RuDSNs leading to a significant enhancement in the intensity. To prove the concept, a single protein molecule at the electrode is initially visualized using the as-prepared RuDSN/AuNPs nanoemitters. Furthermore, the nanoemitter-labeled antibody is linked at the cellular membrane to image a single membrane protein at one cell, without the interference of current and optical background. The success in single-biomolecule ECL imaging solves the long-lasting task in the ultrasensitive ECL analysis, which should be able to provide more elegant information about the protein in cellular biology.

15.
Chem Asian J ; 16(22): 3713-3718, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34533898

RESUMO

Mr. Chen Qian, Dr. Zhimin Ma, Mr. Jianwei Liu, Mrs. Xue Zhang, Prof. Shitao Wang and Prof. Zhiyong Ma. In this article, we report a newly designed molecule composed of a dihydroazulene (DHA) group and a phenothiazine (PTZ) moiety, which achieves aggregation-induced emission enhancement (AIEE), mechanochromism and "gated" solid-state photochromism upon stimulation by an external force. Grinding loosens intermolecular interactions in the crystal and causes a red-shift of fluorescence from 570 nm to 600 nm. Meanwhile, the ring-opening reaction of DHA unit is activated by grinding and a remarkable photochromism could be observed from the grinded powder. The reddish emission of the grinded powder peaked at 600 nm weakened gradually and finally became dark, and a new absorption band at 470 nm emerged in the absorption spectra. Time-dependent density functional theory (TD-DFT) calculation results reveal that the intramolecular intramolecular charge-transfer (ICT) process is replaced by a locally excited (LE) emission on the DHA group, which leads to the quenching of fluorescence. Its impressive photochromic property inspired us to a simple but effective way to develop an encryption system which can let the correct information be displayed upon external stimulation.

16.
Small ; 17(44): e2103406, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34561967

RESUMO

The controlled assembly of nanowires is one of the key challenges in the development of a range of functional 3D aerogels with unique physicochemical properties for practical applications. However, the deep understanding of the dynamic assemble process for fabricating nanowire aerogels remains elusive. Herein, a facile strategy is presented for the metallic ion-induced assembly of nanowires into macroscopic aerogels via a solution-based process. This method enables the interconnecting between polymer-decorated nanowires via metallic coordination, resulting in plenty of nanowire bundles with the same orientation. Besides, the coordinated binding strength of nanowires with different metallic ions is also discussed. The assembly mechanism that the metallic ions induced dynamic behavior of nanowires is revealed via molecular dynamics theoretical evaluation. These findings benefit for constructing nanowire-based aerogels with unique structural features and multi-function, which pave new opportunities for other material systems.

17.
Org Lett ; 23(18): 7069-7073, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34459614

RESUMO

The absolute configuration of rakicidin C was predicted by comparison of optical rotation data and absolute configuration of APD-cyclic depsipeptides and further determined by total synthesis. The absolute configuration of five chiral centers was determined as 2R, 15R, 16R, 17S, and 19S. Our efficient route involves 19 longest linear steps with an overall yield of 1.49%.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34449398

RESUMO

Android is undergoing unprecedented malicious threats daily, but the existing methods for malware detection often fail to cope with evolving camouflage in malware. To address this issue, we present Hawk, a new malware detection framework for evolutionary Android applications. We model Android entities and behavioral relationships as a heterogeneous information network (HIN), exploiting its rich semantic meta-structures for specifying implicit higher order relationships. An incremental learning model is created to handle the applications that manifest dynamically, without the need for reconstructing the whole HIN and the subsequent embedding model. The model can pinpoint rapidly the proximity between a new application and existing in-sample applications and aggregate their numerical embeddings under various semantics. Our experiments examine more than 80,860 malicious and 100,375 benign applications developed over a period of seven years, showing that Hawk achieves the highest detection accuracy against baselines and takes only 3.5 ms on average to detect an out-of-sample application, with the accelerated training time of 50x faster than the existing approach.

19.
Chemphyschem ; 22(20): 2093-2098, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34318995

RESUMO

In this article, we report a newly designed D-A-D' derivative (CNCzPTZ), which displays selective expression of chromophores. This enables CNCzPTZ with solvatochromism, rare dual-mode AIEE properties, solid-state dual-emissions with phosphorescence and distinctive mechanochromism.CNCzPTZ exhibits dual-mode AIEE properties, since the emission band abruptly shifts from 550 nm to 500 nm as the water fraction increases. In the crystalline state, CNCzPTZ demonstrated dual emission bands of 478 nm and 538 nm.CNCzPTZ shows distinctive mechanochromic property in the solid state due to the planarization.

20.
J Am Chem Soc ; 143(32): 12600-12608, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34288654

RESUMO

The kinetics of electrode reactions including mass transfer and surface reaction is essential in electrocatalysis, as it strongly determines the apparent reaction rates, especially on nanostructured electrocatalysts. However, important challenges still remain in optimizing the kinetics of given catalysts with suitable constituents, morphology, and crystalline design to maximize the electrocatalytic performances. We propose a comprehensive kinetic model coupling mass transfer and surface reaction on the nanocatalyst-modified electrode surface to explore and shed light on the kinetic optimization in electrocatalysis. Moreover, a theory-guided microchemical engineering (MCE) strategy has been demonstrated to rationally redesign the catalysts with optimized kinetics. Experimental measurements for methanol oxidation reaction in a 3D ordered channel with tunable channel sizes confirm the calculation prediction. Under the optimized channel size, mass transfer and surface reaction in the channeled microreactor are both well regulated. This MCE strategy will bring about a significant leap forward in structured catalyst design and kinetic modulation.

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