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1.
Ultrasonics ; 118: 106576, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34530394

RESUMO

Compressed sensing-based synthetic transmit aperture (CS-STA) was previously proposed to recover the full radio-frequency (RF) channel dataset of synthetic transmit aperture (STA) from that of a smaller number of randomly apodized plane wave (PW) transmissions. In this way, the imaging frame rate (FR) and contrast are improved with maintained spatial resolution, compared with those of STA. Because CS-STA reconstruction is repeated for all receive elements and RF samples (with a high sampling frequency), the recovery of STA dataset in RF domain is time-consuming. In the meantime, a large amount of RF data needs to be transferred and stored, resulting in an increase of system complexity and required memory space. In this study, CS-STA is extended to in-phase/quadrature (IQ) domain (with lower sampling frequency) for the recovery of baseband STA IQ dataset to accelerate the CS-STA reconstruction by reducing the amount of data to be processed. More importantly, CS-STA reconstruction using IQ data is of practical importance, as clinical ultrasound systems typically record baseband IQ signal instead of RF signal. Simulations, phantom and in vivo experiments verify the feasibility of CS-STA in IQ domain for the recovery of STA dataset. More specifically, CS-STA using IQ data achieves similar image quality and appreciably improves reconstruction speed (by ∼3 times) compared with that using RF data. These findings demonstrate that IQ-domain CS-STA is capable of relieving the computational and storage burdens, which may facilitate the implementation of CS-STA in practical ultrasound systems.

3.
Nanoscale ; 13(30): 12874-12884, 2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34477771

RESUMO

Here, a series of LaFe1-xMnxO3-δ perovskite nanocatalysts were synthesized and tested for the catalytic ozonation of m-cresol for the first time. The B-site cation is regulated by metal doping, and the resulting LaFe0.26Mn0.74O3-δ with a rhombohedral structure showed excellent catalytic performance and structural stability owing to the abundant oxygen vacancies and the higher Fe2+/Fe3+ and Mn3+/Mn4+ ratios. Theoretical calculations have revealed that the oxygen vacancy has a strong affinity for ozone adsorption, and thus facilitated ozone decomposition by extending the O-O bond. Combined with low-valence Fe2+ and Mn3+ cations, the electron transfer in the catalytic ozonation reaction has been enhanced, which has promoted the production of reactive oxygen species (ROS). Taken together, the degradation pathway of m-cresol was proposed. Additionally, the LaFe0.26Mn0.74O3-δ catalyst remained stable during a 60 h reaction. This study has not only revealed the adsorption/decomposition pathways of ozone using LaFe0.26Mn0.74O3-δ perovskite nanocatalysts but also provided indepth insight into the electron transfer pathway on the surface of nanocatalysts during the process of catalytic ozonation.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34482470

RESUMO

A large amount of fresh tobacco waste with high water content are produced in farmland, and it may cause environmental pollution if it is not properly treated. The fresh tobacco waste is not easily collected and transported, resulting in its centralized treatment is expensive. This study is to clarify whether it is feasible to treat fresh tobacco wastes by co-composting of them and soil in farmland and applied the obtained compost product into the soil instead of a part of tobacco-specific fertilizer. The results showed that, compared with that in original soil, the relative abundance of Pseudomonas, Azotobacter, and Coprinus of the co-composted products increased by roughly 244%, 323%, and 675%, respectively, and effective nitrogen and available potassium increased by roughly 157% and 132%, respectively. In addition, the nicotine content in co-composted products decreased dramatically compared with the discarded tobacco leaves. The application of the co-composted products and 20% fertilizer amount (15 g/plant) (YD5) exhibited the highest relative abundance of beneficial microbial communities in the soil and the best growth of tobacco plants. The co-composting of fresh tobacco waste and soil in farmland is an effective measure to treat the fresh tobacco waste, and its products increased beneficial microorganisms and stimulate the growth of tobacco plants by replacing an amount of the fertilizer.

5.
Artigo em Inglês | MEDLINE | ID: mdl-34488343

RESUMO

Organic compounds are promising electrode materials because of their resource sustainability, environmental friendliness, and highly tailorable properties. The porous conjugated polymer shows great potential as an electrode material for its tunable redox nature, conjugated skeleton, and porous structure. Herein, a novel conjugated porous polymer, polydiaminophenylsulfone-triazine, was synthesized by a simple nucleophilic substitution reaction. The conjugated structure and triazine ring can improve the conductivity, charge-transfer efficiency, and physicochemical stability. Also, the porous polymeric framework shows a large specific surface area and high porosity, providing a large contact area with electrolytes and reducing diffusion distance. The polymer demonstrates highly stable cycling performance and good rate capability as an anode for lithium-ion batteries, suggesting a promising strategy to design a competitive electrode material.

6.
Hum Exp Toxicol ; : 9603271211041678, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34488496

RESUMO

Resveratrol has been reported as an ideal medicine in the treatment of colorectal cancer. Meanwhile, cadmium could affect the occurrence and development of tumors in various ways. Epithelial-mesenchymal transition is a major progress regulated with colorectal cancer (CRC). We aimed to determine the effect and mechanism of resveratrol on the Cd-promoted EMT in CRC cells. First, we investigated the migration and invasion of CRC cells with or without the treatment of different concentrations of Cd in vitro by the transwell assay. Second, Western blot and RT-qPCR assay were used to detect the expressions of EMT-related markers (ZEB1, vimentin, E-cadherin, and N-cadherin) in Cd-exposed CRC cells. Subsequently, after treating with different concentrations of resveratrol, the migration and invasion of Cd-exposed CRC cells were detected again, as well as the expressions of EMT-related markers. Moreover, m6A-related RNAs in Cd-exposed CRC cells after treating with resveratrol were immunoprecipitated and validated by Me-RIP and RT-qPCR. These indicated that Cd promoted the migration and invasion of CRC cells. In addition, Cd up-regulated the expressions of N-cadherin, vimentin, and ZEB1, while it down-regulated that of E-cadherin in CRC cells. Resveratrol could reverse the Cd-promoted migration, invasion, and EMT procession by regulating the expression of ZEB1.

7.
Cytotherapy ; 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34465514

RESUMO

BACKGROUND AIMS: Human mesenchymal stem cells (MSCs) from various tissues have emerged as attractive candidates for the prevention and treatment of graft-versus-host disease (GVHD). However, the molecular machinery that defines and channels the behavior of these cells remains poorly understood. METHODS: In this study, the authors compared the efficacy of four tissue-derived MSC types in controlling GVHD in a murine model and investigated their immunomodulatory effects. RESULTS: Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) effectively decreased the incidence and severity of GVHD, which was mediated by the enrichment of myeloid-derived suppressor cells in GVHD target tissues. RNA sequencing results showed that hUCMSCs highly expressed CXCL1. CONCLUSIONS: These results suggest a novel prophylactic application of hUCMSCs for controlling GVHD after allogeneic hematopoietic stem cell transplantation.

8.
Cell Prolif ; : e13116, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469018

RESUMO

OBJECTIVES: The discrepancy between supply and demand of organ has led to an increased utilization of steatotic liver for liver transplantation (LT). Hepatic steatosis, however, is a major risk factor for graft failure due to increased susceptibility to ischaemia-reperfusion (I/R) injury during transplantation. MATERIALS AND METHODS: To assess the plasticity and phenotype of immune cells within the microenvironment of steatotic liver graft at single-cell level, single-cell RNA-sequencing (scRNA-Seq) was carried out on 23 675 cells from transplanted rat livers. Bioinformatic analyses and multiplex immunohistochemistry were performed to assess the functional properties, transcriptional regulation, phenotypic switching and cell-cell interactions of different cell subtypes. RESULTS: We have identified 11 different cell types in transplanted livers and found that the highly complex ecosystem was shaped by myeloid-derived cell subsets that transit between different states and interact mutually. Notably, a pro-inflammatory phenotype of Kupffer cells (KCs) with high expression of colony-stimulating factor 3 (CSF3) that was enriched in transplanted steatotic livers was potentially participated in fatty graft injury. We have also detected a subset of dendritic cells (DCs) with highly expressing XCR1 that was correlated with CD8+ T cells, mediating the severer steatotic liver damage by I/R injury. CONCLUSIONS: The findings of our study provide new insight into the mechanisms by which steatosis exacerbates liver damage from I/R injury. Interventions based on these observations create opportunities in attenuating fatty liver graft injury and expanding the donor pool.

9.
Artigo em Inglês | MEDLINE | ID: mdl-34477299

RESUMO

Exploration of effective ways to integrate various functional species into hydrogen-bonded organic frameworks (HOFs) is critically important for their applications but highly challenging. In this study, according to the "bottle-around-ship" strategy, core-shell heterostructure of upconversion nanoparticles (UCNPs) and HOFs was first time fabricated via a ligand-grafting stepwise method. UCNPs "core" can effectively upconvert near-infrared (NIR) irradiation (980 nm) into visible light (540 nm and 653 nm), which further excites the perylenediimide-based HOF "shell" through resonance energy transfer. In this way, the nanocomposite inherits the high porosity, excellent photothermal and photodynamic efficiency, NIR photoresponse from two parent materials, achieving intriguing NIR-responsive bacterial inhibition toward Escherichia coli . This study may shed light on the design of functional HOF-based composite materials, not only enriching the HOF library but also broadening the horizon of their potential applications.

10.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2633-2644, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34472284

RESUMO

Endothelial cells that form the inner layers of both blood and lymphatic vessels are important components of the vascular system and are involved in the pathogenesis of vascular and lymphatic diseases. Angiopoietin (Ang)-Tie axis in endothelial cells is the second endothelium-specific ligand-receptor signaling system necessary for embryonic cardiovascular and lymphatic development in addition to the vascular endothelial growth factor receptor pathway. The Ang-Tie axis also maintains vascular homeostasis by regulating postnatal angiogenesis, vessel remodeling, vascular permeability, and inflammation. Therefore, the dysfunction of this system leads to many vascular and lymphatic diseases. In light of the recent advances on the role of the Ang-Tie axis in vascular and lymphatic system-related diseases, this review summarizes the functions of the Ang-Tie axis in inflammation-induced vascular permeability, vascular remodeling, ocular angiogenesis, shear stress response, atherosclerosis, tumor angiogenesis, and metastasis. Moreover, this review summarizes the relevant therapeutic antibodies, recombinant proteins, and small molecular drugs associated with the Ang-Tie axis.


Assuntos
Angiopoietinas , Doenças Linfáticas , Células Endoteliais/metabolismo , Humanos , Sistema Linfático/metabolismo , Receptor TIE-2/genética , Receptor TIE-2/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular
11.
Microbiol Resour Announc ; 10(36): e0054221, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34498928

RESUMO

Synechococcus cultures in the laboratory are often associated with heterotrophic bacteria. Here, we report the genome sequence of the bacterium Microbacterium sp. strain R1, isolated from a culture of the estuarine Synechococcus strain CBW1107. Several secondary metabolites and transporter-related genes were identified in the genome of Microbacterium sp. strain R1.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34498949

RESUMO

SIGNIFICANCE: Hydrogen sulfide (H2S) is an endogenous signaling molecule, regulating numerous physiological functions from vasorelaxation to neuromodulation. Iron is a well-known bioactive metal ion, being the central component of hemoglobin for oxygen transportation and participating in biomolecule degradation, redox balance, and enzymatic actions. The interplay between H2S and iron metabolisms and functions impact significantly on the fate and wellness of different types of cells. Recent advances: Iron level in vivo affects the production of H2S via non-enzymatic reactions. On the other hand, H2S quenches excessive iron inside the cells and regulates the redox status of iron. CRITICAL ISSUES: Abnormal metabolisms of both iron and H2S are associated with various conditions and diseases like iron overload, anemia, oxidative stress, cardiovascular and neurodegenerative diseases. The molecular mechanisms for the interactions of H2S and iron are unsettled yet. Here we review signaling links of the production, metabolism and their respective and integrative functions of H2S and iron in normalcy and diseases. Future direction: Physiological and pathophysiological importance of H2S and iron as well as their therapeutic applications should be evaluated jointly, not separately. Future investigation should expand from iron-rich cells and tissues to the others in which H2S and iron interaction has not received due attention.

13.
Dalton Trans ; 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34505851

RESUMO

Transition-metal selenides are regarded as promising electrode materials due to their superior electrochemical performances for supercapacitors. In this study, a nanorod-like hybrid of Ni0.85Se@Cu2-xSe on a Ni-foam substrate is successfully synthesized via a facile one-step route. The Ni0.85Se@Cu2-xSe nanorods are found to be deposited uniformly on the Ni-form substrates. When used as a battery-type electrode in a supercapacitor, the as-deposited Ni0.85Se@Cu2-xSe electrode exhibits a high specific capacity of 1831 F g-1 at 1 A g-1 and 78.4% of capacitance retention after 8000 cycles at 10 A g-1. Moreover, the assembled Ni0.85Se@Cu2-xSe//AC asymmetric supercapacitor (ASC) exhibits an energy density of 63.2 W h kg-1 at a power density of 800.1 W kg-1, as well as good cycling stability (92.1% capacitance retention after 5000 cycles).

15.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2931-2941, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467683

RESUMO

As a new strategy capable of uncovering the characteristics of traditional Chinese medicines, the quantitative analysis of multi-components by single-marker(QAMS) has been widely employed for the quality evaluation of Chinese medicinal materials, slices, and extracts. However, its application in the assessment of Chinese patent medicines is yet to be explored. By referring to the determination of three bufogenins in Bufonis Venenum by QAMS described in Chinese Pharmacopoeia(2020 Edition), this paper selected seven representative preparations containing Bufonis Venenum and explored whether the relative correction factors(RCFs) of cinobufagin(CB) to bufalin(BF) and resibufogenin(RB) could be directly used for the quality control of Bufonis Venenum-contained preparations. Based on the qualitative analyses under the same chromatographic conditions as used for toad venom, combing specificity test, five preparations such as Yatong Yili Pills, Houzheng Pills, Xiongdan Jiuxin Pills, Liushen Pills and Niuhuang Xiaoyan Pills, were expected to use validated RCFs for the direct determination of three components. Taking Houzheng Pills as an example, the methodological validation of bufalin, cinobufagin and resibufogenin was carried out, and the recoveries of bufalin, cinobufagin and resibufogenin were 90.64%-106.1%. The obvious difference was not observed between the contents of bufalin and resibufogenin in 24 batches of preparation samples by QAMS and external reference method. In the tested samples, the content of bufalin, cinobufagin and resibufogenin were 1.27-2.61, 2.44-5.66 and 0.988-3.16 mg·g~(-1) in 10 batches of Liushen Pills samples. The contents of bufalin, cinobufagin and resibufogenin were 0.760-1.32, 1.35-2.39 and 0.600-1.55 mg·g~(-1) in 10 batches of Houzheng Pills samples from three manufacturers. The obtained data contribute to improving the quality standard of Bufonis Venenum-contained preparations, and they also provide some ideas for the application of QAMS in the quality evaluation and control of Chinese patent medicines.


Assuntos
Medicina Tradicional Chinesa , Medicamentos sem Prescrição , China , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
16.
Zhongguo Zhong Yao Za Zhi ; 46(12): 3133-3143, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467705

RESUMO

To study the effect of mineral Chloriti Lapis on pulmonary metabolites and metabolic pathways in lung tissues of rats with acute exacerbation of chronic obstructive pulmonary disease(AECOPD). The AECOPD rat model of phlegm heat syndrome was replicated by the method of smoking combined with Klebsiella pneumoniae infection. Except for using UPLC-Q-TOF-MS analysis, SPSS 18.0, SIMCA 13.0 and other software were also used for statistical analysis. Through literature search and online database comparison, the differential metabolites were identified, and the possible metabolic pathways were analyzed. After 15 days of administration, PLS-DA analysis was carried out on lung tissue samples of rats in each group. The results showed that the metabolic profiles of lung tissues of rats in each group could be well separated, which indicated that Chloriti Lapis and aminophylline had significant intervention effect on the lung metabolic profile of rats with AECOPD. Moreover, the metabolic profile of Chloriti Lapis group was closer to that of control group, and the intervention effect was better than that of aminophylline group. As a result, 15 potential differential metabolites were identified: phytosphingosine, sphinganine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], lysoPC(18∶0), stearic acid, lysoPC(15∶0), arachidonic acid, docosapentaenoic acid, linoleic acid and palmitic acid. Among them, Chloriti Lapis could significantly improve the levels of 10 differential metabolites of phytosphingosine, tetradecanoylcarnitine, L-palmitoylcarnitine, elaidic carnitine, lysoPC[18∶2(9Z,12Z)], lysoPC(16∶0), lysoPC[18∶1(9Z)], stearic acid, lysoPC(15∶0), and palmitic acid(P<0.05). The intervention effect of Chloriti Lapis group was better than that of aminophylline group. Analysis of metabolic pathways showed that there were 8 possible metabolic pathways that could be affected, and three of the most important metabolic pathways(pathway impact>0.1) were involved: linoleic acid metabolism, arachidonic acid metabolism, and sphingolipid metabolism. Chloriti Lapis had obvious intervention effects on lung tissue-related metabolites and metabolic pathways in rats with AECOPD, and the effect was better than that of aminophyllinne.


Assuntos
Medicina Tradicional Chinesa , Doença Pulmonar Obstrutiva Crônica , Animais , Pulmão , Metabolômica , Minerais , Ratos
17.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4069-4082, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34467716

RESUMO

Trigonella foenum-graecum is an annual plant of the genus Trigonella in the Leguminosae family. It is widely distributed in China and has a long history of application. According to phytochemistry research, the seeds, stem, and leaves of this herb contain not only a variety of bioactive ingredients, including alkaloids, saponins, polysaccharides, flavonoids, and phenols, but also abundant nutrients such as unsaturated fatty acids and amino acids and various trace elements. Pharmacological studies have shown that both the extract of T. foenum-graecum and its chemical constituents exhibit hypoglycemic, hypolipidemic, antitumor, antioxidative, antimicro-bial, and hepatoprotective activities. This paper reviews the research progress on the chemical constituents and pharmacological effects of T. foenum-graecum, which may contribute to further development, application, and clinical research of this herb.


Assuntos
Trigonella , Antioxidantes/farmacologia , Hipoglicemiantes , Extratos Vegetais/farmacologia , Sementes
18.
Adv Sci (Weinh) ; 8(13): 2100424, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34540558

RESUMO

Herein, a set of optogenetic tools (designated LiPOP) that enable photoswitchable necroptosis and pyroptosis in live cells with varying kinetics, is introduced. The LiPOP tools allow reconstruction of the key molecular steps involved in these two non-apoptotic cell death pathways by harnessing the power of light. Further, the use of LiPOPs coupled with upconversion nanoparticles or bioluminescence is demonstrated to achieve wireless optogenetic or chemo-optogenetic killing of cancer cells in multiple mouse tumor models. LiPOPs can trigger necroptotic and pyroptotic cell death in cultured prokaryotic or eukaryotic cells and in living animals, and set the stage for studying the role of non-apoptotic cell death pathways during microbial infection and anti-tumor immunity.

19.
Org Lett ; 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34543571

RESUMO

Aldehydes and aziridines are both intrinsic electrophilic reagents, and thus the coupling reaction between these two compounds is highly challenging. In this protocol, the merger of nickel and hydrogen-atom-transfer photocatalysis successfully enables the ring opening of N-tosyl styrenyl aziridines with aldehydes, providing a novel and atom-economical access to a variety of ß-amino ketones with complete regiocontrol. The preliminary mechanistic studies reveal that the ring opening reaction proceeds with a cooperative catalytic mode: aldehydes are converted into acyl radicals by tetrabutylammonium decatungstate under irradiation, whereas the nickel catalyst is engaged in the ring opening of aziridines and the following carbon-carbon bond-forming step.

20.
J Integr Med ; 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34544670

RESUMO

BACKGROUND: Influenza places a heavy public health burden in numerous countries every year. In addition to vaccines, there are some interventions that are effective in preventing influenza. OBJECTIVE: This overview of systematic reviews (SRs) aimed to evaluate the efficacy and safety of interventions for influenza prevention. SEARCH STRATEGY: We searched the Cochrane Database of Systematic Reviews, 2020, Issue 1 for relevant Cochrane SRs using the keywords "common cold," "influenza," and "flu." INCLUSION CRITERIA: Cochrane SRs that investigated the prevention of influenza were included. Participants included the general population without influenza or influenza-like symptoms, who were treated with preventative interventions and compared to individuals receiving no treatment or placebo. DATA EXTRACTION AND ANALYSIS: Two reviewers independently screened citations against pre-defined inclusion criteria and extracted data. The methodological quality of these SRs was evaluated using the Assessing the Methodological Quality of Systematic Reviews-II (AMSTAR-II) guidelines. The primary outcome of our analysis was the incidence of influenza, and the secondary outcomes were the incidence of influenza-like illness and hospitalization. In addition to the narrative summary of SR findings, we also pooled data from homogeneous trials among these SRs and produced evidence mapping. We conducted a network meta-analysis to compare the effect across interventions and used the Cochrane approach to grading of recommendations, assessment, development, and evaluation (GRADE) to assess the quality of evidence. RESULTS: Eleven Cochrane SRs were included, covering five medications, eleven vaccinations and four complementary therapies. Among these SRs, 73% scored "high" quality on AMSTAR-II rating. We found that eight interventions, including amantadine, garlic, and six different vaccines, were beneficial for reducing the incidence of influenza compared to placebo, while oseltamivir, zanamivir, Ganmao capsule, Echinacea, and another three types of vaccine were probably beneficial. Ganmao capsule ranked highest for influenza prevention in the network meta-analysis, followed by amantadine, garlic, and vaccines of all types. Monovalent inactivated parenteral vaccine was found to be beneficial in reducing the incidence of influenza-like illness. None of the interventions reduced the hospitalization rate. CONCLUSION: High-quality evidence showed that garlic or vaccine had advantages in preventing influenza, and that vitamin C is not effective. The effect of other interventions needs to be further verified with high-quality evidence.

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