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1.
BMC Plant Biol ; 24(1): 600, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926811

RESUMO

BACKGROUND: Delphinium L. represents a taxonomically intricate genus of significant phylogenetic and economic importance in Ranunculaceae. Despite the existence of few chloroplast genome datasets, a comprehensive understanding of genome structures and selective pressures within the genus remains unknown. Furthermore, several taxa in this genus are exclusively found in Xinjiang, China, a region renowned for its distribution and diversity of Chinese and Central Asian Delphinium species. Therefore, investigating the features of chloroplast genomes in this area will provide valuable insights into the evolutionary processes and phylogenetic relationships of the genus. RESULTS: In this study, the eight newly completed chloroplast genomes are examined, ranging in length from 153,979 bp to 154,284 bp. Alongside these, analysing six previously reported taxa re-annotated in Delphinium, 111 unique genes are identified across all samples. Genome structure, distributions of simple sequence repeats and short dispersed repeats, as well as gene content are similar among these Delphinium taxa. Nine hypervariable intergenic spacers and protein coding regions, including ndhF-trnL(TAG), rpl16-intron, rpl33, rps15, rps18, trnK(TTT)-trnQ(TTG), trnP(TGG)-psaJ, trnT(GGT)-psbD and ycf1, are identified among 13 perennial Delphinium. Selective pressure and codon usage bias of all the plastid genes are performed within 14 Delphinium taxa. Phylogenetic analysis based on 14 Delphinium plastomes, alongside two Aconitum (Ranunculaceae) species serving as outgroup taxa, reveals the monophyletic nature of Delphinium. Our findings further discern Delphinium into two distinct clades: perennial species (clade I) and annual species (clade II). In addition, compared with the nrDNA ITS topology, cytological data and morphological characters, D. mollifolium and D. maackianum showed potential involvement in hybridization or polyploidization processes. Excluding these two species, the perennial Delphinium (clade I) exhibits a stronger consistency with the morphology-based system that utilized seed morphology. CONCLUSION: This study represents the first comprehensive analysis of plastomic variations among Delphinium taxa, based on the examination of 14 complete plastomes. The chloroplast genome structure of Delphinium is similar to other angiosperms and possesses the typical quadripartite structure with the conserved genome arrangement and gene features. In addition, the variation of non-coding regions is larger than coding regions of the chloroplast genome. Through DNA sequence divergence across Delphinium plastomes and subsequent phylogenomic analyses ndhF-trnL(TAG) and ycf1 are identified as promising molecular markers. These highly variable loci held significant potential for future phylogenetic and phylogeographic studies on Delphinium. Our phylogenomic analyses based on the whole plastomes, concatenation of 132 unique intergenic spacer regions, concatenation of 77 unique protein-coding genes and nrDNA ITS, all support the monophyly of Delphinium and perennial taxa clusters together into one clade within this genus. These findings provide crucial data for systematic, phylogenomic and evolutionary research in the genus for future studies.


Assuntos
Delphinium , Genoma de Cloroplastos , Filogenia , Delphinium/genética , Delphinium/classificação , China , Ranunculaceae/genética , Ranunculaceae/classificação
2.
Cell Signal ; 120: 111196, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38697448

RESUMO

Triple negative breast cancer (TNBC) is insensitive to conventional targeted therapy and endocrine therapy, and is characterized by high invasiveness and high recurrence rate. This study aimed to explore the role and mechanism of RHOXF2 and HOXC13 on the malignant progression of TNBC. RT-qPCR and western blot were used to detect RHOXF2 and HOXC13 expression in TNBC cells. The proliferation, colony formation, invasion, migration, apoptosis and cell cycle of TNBC cells after transfection were analyzed by CCK-8 assay, colony formation assay, transwell assay, wound healing assay and flow cytometry analysis. Co-Immunoprecipitation and GST pull-down assays were used to analyze the combination between RHOXF2 and HOXC13. ChIP-PCR and luciferase reporter gene assay were used to examine the regulation of H3K27ac on RHOXF2. Besides, the expression of Ki67 and cleaved Caspase3 in tumor tissues of nude mice was determined by immunofluorescence. Results revealed that RHOXF2 and HOXC13 expression was increased in TNBC cells. RHOXF2 knockdown suppressed the proliferation, invasion and migration, as well as induced G0/G1 cell cycle arrest and apoptosis of TNBC cells. Besides, RHOXF2 could bind to HOXC13 and RHOXF2 knockdown suppressed HOXC13 expression in TNBC cells. Furthermore, HOXC13 overexpression reversed the impacts of RHOXF2 downregulation on the proliferation, invasion, migration, G0/G1 cell cycle arrest and apoptosis of TNBC cells. In addition, RHOXF2 silencing limited the tumor volume in nude mice, which was reversed by HOXC13 overexpression. Moreover, RHOXF2 knockdown interfered with Wnt2/ß-catenin pathway in vitro and in vivo by binding to HOXC13. Importantly, H3K27ac acetylation could activate the expression of RHOXF2 promoter region. In conclusion, RHOXF2 activated by H3K27ac functioned as a tumor promoter in TNBC via mediating Wnt2/ß-catenin pathway by binding to HOXC13, which provided promising insight into exploration on TNBC therapy.


Assuntos
Movimento Celular , Proliferação de Células , Proteínas de Homeodomínio , Camundongos Nus , Neoplasias de Mama Triplo Negativas , Via de Sinalização Wnt , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Animais , Feminino , Via de Sinalização Wnt/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Histonas/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Progressão da Doença , beta Catenina/metabolismo
3.
Chemosphere ; 349: 140903, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38092167

RESUMO

CO2 absorption-microalgae conversion (CAMC) system is a promising carbon capture and utilization technology. However, the use of HCO3- as a carbon source often led to a slower growth rate of microalgae, which also limited the application of CAMC system. In this study, the assimilation efficiency of HCO3- in CAMC system was improved through mixotrophic, and the potential mechanism was investigated. The HCO3- assimilation efficiency and biomass under mixotrophic were 34.79% and 31.76% higher than that of control. Mixotrophic increased chlorophyll and phycocyanin content, which were beneficial to capture more light energy. The content of ATP and NADPH reached 566.86 µmol/gprot and 672.86 nmol/mgprot, which increased by 31.83% and 27.67% compared to autotrophic. The activity of carbonic anhydrase and Rubisco increased by 18.52% and 22.08%, respectively. Transcriptome showed that genes related to photosynthetic and respiratory electron transport were up-regulated. The synergy of photophosphorylation and oxidative phosphorylation greatly improved energy metabolism efficiency, thus accelerating the assimilation of HCO3-. These results revealed a potential mechanism of promoting the HCO3- assimilation under mixotrophic, it also provided a guidance for using CAMC system to serve carbon neutrality.


Assuntos
Bicarbonatos , Microalgas , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Fotossíntese , Carbono/metabolismo , Biomassa
4.
Sci Total Environ ; 904: 166919, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37689188

RESUMO

Global soil cadmium (Cd(II)) contamination threatens the soil environment, food safety, and human health. Conventional electrokinetic remediation (EKR) and enhancement methods usually operate in strong electric fields, leading to strong side reactions and uneven removal. In this work, to remove Cd(II) from soil effectively in a low-voltage electric field, a new-style electrokinetic-adsorption remediation using double-group electrodes coupled with chitosan-activated carbon composite membranes (DE-EKR-CAC) was developed. Chitosan-activated carbon (CAC) composite membranes were synthesized for easy recovery and reuse of adsorbents. The effects of pH, contact time, initial concentration, and foreign ions on the removal of Cd(II) by the CAC composite membranes were determined. The CAC composite membranes performed well except in a strongly acidic environment (pH = 2.0). The soil pH varied between 3.4 and 5.0 in DE-EKR-CAC, where the CAC composite membranes were applicable. High concentrations of Ca2+ interfered with the adsorption of Cd(II), which means that the selectivity of CAC composite membranes for Cd(II) is not high enough. The Langmuir (R2 = 0.999) and pseudo-second-order kinetic (R2 = 1.0) models revealed the monolayer coverage and chemisorption mechanism, and the maximum adsorption capacity was 40.81 mg/g. Furthermore, SEM, FTIR, and XPS analyses suggest that physical adsorption, complexation of oxygen-containing functional groups, chelation of amino groups, and ion exchange are potential mechanisms for the adsorption of Cd(II) on CAC. DE-EKR-CAC performed better than the group remediated with one set of electrodes, with higher removal efficiencies and more uniform removal. The lowest energy consumption was 3.33 kWh/m3, which is lower than other enhancement methods. Separation of CAC composite membranes from soil is easy, and reuse performance is good. DE-EKR-CAC provides a potential option for Cd(II) removal from soil because of its better performance using low-voltage direct current, low energy consumption, and ease of recycling the adsorbent.

5.
BMC Plant Biol ; 23(1): 444, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37730528

RESUMO

BACKGROUND: The genus Sanicula comprises ca. 45 taxa, widely distributed from East Asia to North America, which is a taxonomically difficult genus with high medicinal value in Apiaceae. The systematic classification of the genus has been controversial for a long time due to varied characters in key morphological traits. China is one of the most important distributed centers, with ca. 18 species and two varieties. At present, chloroplast genomes are generally considered to be conservative and play an important role in evolutionary relationship study. To investigate the plastome evolution and phylogenetic relationships of Chinese Sanicula, we comprehensively analyzed the structural characteristics of 13 Chinese Sanicula chloroplasts and reconstructed their phylogenetic relationships. RESULTS: In present study, four newly complete chloroplast genome of Sanicula taxa by using Illumina sequencing were reported, with the typical quadripartite structure and 155,396-155,757 bp in size. They encoded 126 genes, including 86 protein-coding genes, 32 tRNA genes and 8 rRNA genes. Genome structure, distributions of SDRs and SSRs, gene content, among Sanicula taxa, were similar. The nineteen intergenic spacers regions, including atpH-atpI, ndhC-trnM, petB-petD, petD-rpoA, petN-psbM, psaJ-rpl33, rbcL-accD, rpoB-trnC, rps16-trnQ, trnE-psbD, trnF-ndhJ, trnH-psbA, trnN-ndhF, trnS-psbZ, trnS-trnR, trnT-trnF, trnV-rps12, ycf3-trnS and ycf4-cemA, and one coding region (ycf1 gene) were the most variable. Results of maximum likelihood analysis based on 79 unique coding genes of 13 Chinese Sanicula samples and two Eryngium (Apiaceae-Saniculoideae) species as outgroup taxa revealed that they divided into four subclades belonged to two clades, and one subclade was consistent with previously traditional Sanicula section of its system. The current classification based on morphology at sect. Sanicla and Sect. Tuberculatae in Chinese Sanicula was not supported by analysis of cp genome phylogeny. CONCLUSIONS: The chloroplast genome structure of Sanicula was similar to other angiosperms and possessed the typical quadripartite structure with the conserved genome arrangement and gene features. However, their size varied owing to expansion/contraction of IR/SC boundaries. The variation of non-coding regions was larger than coding regions of the chloroplast genome. Phylogenetic analysis within these Chinese Sanicula were determined using the 79 unique coding genes. These results could provide important data for systematic, phylogenomic and evolutionary research in the genus for the future studies.


Assuntos
Apiaceae , Sanicula , Filogenia , China , Cloroplastos/genética , DNA Intergênico
6.
IEEE Trans Pattern Anal Mach Intell ; 45(12): 15996-16012, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37531304

RESUMO

Semantic segmentation has achieved huge progress via adopting deep Fully Convolutional Networks (FCN). However, the performance of FCN-based models severely rely on the amounts of pixel-level annotations which are expensive and time-consuming. Considering that bounding boxes also contain abundant semantic and objective information, an intuitive solution is to learn the segmentation with weak supervisions from the bounding boxes. How to make full use of the class-level and region-level supervisions from bounding boxes to estimate the uncertain regions is the critical challenge for the weakly supervised learning task. In this paper, we propose a mixture model to address this problem. First, we introduce a box-driven class-wise masking model (BCM) to remove irrelevant regions of each class. Moreover, based on the pixel-level segment proposal generated from the bounding box supervision, we calculate the mean filling rates of each class to serve as an important prior cue to guide the model ignoring the wrongly labeled pixels in proposals. To realize the more fine-grained supervision at instance-level, we further propose the anchor-based filling rate shifting module. Unlike previous methods that directly train models with the generated noisy proposals, our method can adjust the model learning dynamically with the adaptive segmentation loss. Thus it can help reduce the negative impacts from wrongly labeled proposals. Besides, based on the learned high-quality proposals with above pipeline, we explore to further boost the performance through two-stage learning. The proposed method is evaluated on the challenging PASCAL VOC 2012 benchmark and achieves 74.9 % and 76.4 % mean IoU accuracy under weakly and semi-supervised modes, respectively. Extensive experimental results show that the proposed method is effective and is on par with, or even better than current state-of-the-art methods.

7.
Chemistry ; 29(41): e202300993, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37154210

RESUMO

A polymer-stabilized liquid crystal (PSLC)-based environment-adaptative smart window with multi-modulations is demonstrated. This PSLC system contains a right-handed dithienyldicyanoethene-based chiral photoswitch and a chiral dopant, S811, with opposite handedness, of which the reversible cis-trans photoisomerization of the switch can drive self-shading of the smart window under UV light stimulus because of the transition from nematic phase to cholesteric one. With the assistance of solar heat, the opacity of the smart window can be deepened because the heat promotes the isomerization conversion rate of the switch. This switch has no thermal relaxation at room temperature, therefore, the smart window exhibits dual stabilization: transparent state (cis-isomer) and opaque state (trans-isomer). Moreover, the incident intensity of sunlight can be regulated by an electric field, which allows the smart window to adapt to some specific situations. Such an energy-saving device can be used in buildings and vehicles to control indoor temperature and adapt to the required ambiance.

8.
ACS Appl Mater Interfaces ; 15(21): 26037-26046, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37194604

RESUMO

Developing circularly polarized room-temperature phosphorescent (CPRTP) materials with a high dissymmetry factor (glum) and long afterglow is very attractive but highly challenging. Here, a CPRTP emission featuring ultrahigh glum value and desired visualization characteristic in a bilayer composite photonic film is achieved for the first time. In the constructed system, N and P co-doped carbonized polymer dots (NP-CPDs) are dispersed into polyvinyl alcohol (PVA) as the phosphorescent emitting layer, and helically structured cholesteric polymer films are used as selective reflective layers to convert the unpolarized emission of NP-CPDs into circularly polarized emission. On the basis of the modulation of the helical structure period of the cholesteric polymer, the bilayer composite film enables NP-CPDs to obtain a high glum value. Notably, the optimized photonic film emits CPRTP with glum as high as 1.09 and a green afterglow lasting above 8.0 s. Moreover, the composite photonic array films featuring information encryption characteristics are developed by modulating the liquid crystal phase of the cholesteric polymer film and the dot coating position of the NP-CPDs/PVA layer, thus expanding the application of CPRTP materials in cryptography and anti-counterfeiting.

9.
IEEE Trans Pattern Anal Mach Intell ; 45(2): 1963-1980, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35417346

RESUMO

Thanks to the advent of deep neural networks, recent years have witnessed rapid progress in person re-identification (re-ID). Deep-learning-based methods dominate the leadership of large-scale benchmarks, some of which even surpass the human-level performance. Despite their impressive performance under the single-domain setup, current fully-supervised re-ID models degrade significantly when transplanted to an unseen domain. According to the characteristics of the re-ID task, such degradation is mainly attributed to the dramatic variation within the target domain and the severe shift between the source and target domain, which we call dual discrepancy in this paper. To achieve a model that generalizes well to the target domain, it is desirable to take such dual discrepancy into account. In terms of the former issue, a prevailing solution is to enforce consistency between nearest-neighbors in the embedding space. However, we find that the search of neighbors is highly biased in our case due to the discrepancy across cameras. For this reason, we equip the vanilla neighborhood invariance approach with a camera-aware learning scheme. As for the latter issue, we propose a novel cross-domain mixup scheme. It works in conjunction with virtual prototypes which are employed to handle the disjoint label space between the two domains. In this way, we can realize the smooth transfer by introducing the interpolation between the two domains as a transition state. Extensive experiments on four public benchmarks demonstrate the superiority of our method. Without any auxiliary models and offline clustering procedure, it achieves competitive performance against existing state-of-the-art methods. The code is available at https://github.com/LuckyDC/generalizing-reid-improved.

10.
IEEE Trans Pattern Anal Mach Intell ; 45(3): 2801-2815, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35704543

RESUMO

Gait recognition plays a special role in visual surveillance due to its unique advantage, e.g., long-distance, cross-view and non-cooperative recognition. However, it has not yet been widely applied. One reason for this awkwardness is the lack of a truly big dataset captured in practical outdoor scenarios. Here, the "big" at least means: (1) huge amount of gait videos; (2) sufficient subjects; (3) rich attributes; and (4) spatial and temporal variations. Moreover, most existing large-scale gait datasets are collected indoors, which have few challenges from real scenes, such as the dynamic and complex background clutters, illumination variations, vertical view variations, etc. In this article, we introduce a newly built big outdoor gait dataset, called CASIA-E. It contains more than one thousand people distributed over near one million videos. Each person involves 26 view angles and varied appearances caused by changes of bag carrying, dressing and walking styles. The videos are captured across five months and across three kinds of outdoor scenes. Soft biometric features are also recorded for all subjects including age, gender, height, weight, and nationality. Besides, we report an experimental benchmark and examine some meaningful problems that have not been well studied previously, e.g., the influence of million-level training videos, vertical view angles, walking styles, and the thermal infrared modality. We believe that such a big outdoor dataset and the experimental benchmark will promote the development of gait recognition in both academic research and industrial applications.


Assuntos
Algoritmos , Marcha , Reconhecimento Automatizado de Padrão , Humanos , Gravação de Videoteipe , Caminhada , Aprendizado Profundo , Biometria
11.
Sci Total Environ ; 858(Pt 2): 159920, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356767

RESUMO

Mixotrophic cultivation was proposed to enhance the biomass and carbon sequestration efficiency of Spirulina in CO2 absorption and microalgae conversion (CAMC) system, and the underlying metabolic mechanism was also explored. The result showed that mixotrophic enhanced the performance of CAMC system, the maximum biomass, total carbon conversion capacity and efficiency was obtained at 0.5 g/L acetate group, which was 60.47 %, 63.06 % and 59.77 % higher than control. Adding 0.5 g/L acetate enhanced the activities of Rubisco and Acetyl-CoA, arrived at 89.59 U/g and 5.16 nmol/g, respectively. Metabolomics analyses suggested that mixotrophic changed metabolic flux and affected intracellular composition. Mixotrophic up-regulated Calvin cycle, glycolysis, and tricarboxylic acid (TCA) cycle, induced more carbon fluxes into central carbon metabolism for the growth of Spirulina. These results suggested that mixotrophic could supply effective energy and carbon skeleton for rapid growth of Spirulina, and provided a theoretical basis for large-scale application of CAMC system.


Assuntos
Microalgas , Spirulina , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Biomassa , Carbono/metabolismo , Acetatos/metabolismo , Metabolômica
12.
Mitochondrial DNA B Resour ; 7(7): 1199-1200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814182

RESUMO

Hydrocotyle pseudoconferta was an important medicinal plant. The complete plastid genome of this species was reported for the first time. The full length of the complete chloroplast genome is 153,302 bp, with a typical quadripartite organization: a large single-copy (LSC) region of 84,417 bp, a small single-copy (SSC) region of 18,767 bp, and a pair inverted repeat regions (IRa and IRb) with 25,059 bp for each. The complete chloroplast genome of H. pseudoconferta encoded 133 genes, comprising 86 protein-coding genes, 37 tRNA genes, 8 rRNA genes, and 2 pseudogenes. The phylogenetic analysis suggested the closest relationship between H. pseudoconferta and Hydrocotyle nepalensis.

13.
ChemSusChem ; 15(16): e202200702, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35778818

RESUMO

Constructing metal-organic frameworks (MOFs) with high volatile organic compounds (VOCs) adsorption capacity and excellent water resistance remain challenging. Herein, a monocarboxylic acid-assisted mixed ligands strategy was designed to synthesize a novel fluorinated MOFs, MIL-53 (Al). The monocarboxylic acid promoted crystallization and produced abundant crystal defects, which increased pore volume. Moreover, the competitive coordination between tetrafluoroterephthalic acid and 1,4-dicarboxybenzene was moderated by monocarboxylic modulators, significantly improving the hydrophobicity. The toluene uptake of the optimal sample reached 254.85 mg g-1 under humid conditions, increased by 33.56 % of MIL-53(Al), and the QWet /QDry (the ratio of adsorption quality under wet to adsorption quality under dry) was 0.92, remarkably surpassing that of origin MIL-53 (0.72). The recycle experiment showed superior reusability with no performance degradation after 10 recycle under RH=50 % (relative humidity). The adsorptive kinetic and thermodynamic analysis proves that the adsorption process is controlled by surface mono-layer adsorption and pore diffusion. The fluorine group affects the internal diffusion, which weakens the transfer rate. This strategy opens a new prospect of obtaining hierarchical functional MOFs for meeting the VOCs uptake under the practical application.

14.
Environ Sci Technol ; 56(14): 9854-9871, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35635373

RESUMO

The severe hazard of chlorinated volatile organic compounds (CVOCs) to human health and the natural environment makes their abatement technology a key topic of global environmental research. Due to the existence of Cl, the byproducts of CVOCs in the catalytic combustion process are complex and toxic, and the possible generation of dioxin becomes a potential risk to the environment. Well-qualified CVOC catalysts should process favorable low-temperature catalytic oxidation ability, excellent selectivity, and good resistance to poisoning, which are governed by the reasonable adjustment of acidity and redox properties. This review overviews the application of different types of multicomponent catalysts, that is, supported noble metal catalysts, transition metal oxide/zeolite catalysts, composite transition metal oxide catalysts, and acid-modified catalysts, for CVOC degradation from the perspective of balance between acidity and redox properties. This review also highlights the synergistic degradation of CVOCs and NOx from the perspective of acidity and redox properties. We expect this work to inspire and guide researchers from both the academic and industrial communities and help pave the way for breakthroughs in fundamental research and industrial applications in this field.


Assuntos
Compostos Orgânicos Voláteis , Catálise , Humanos , Metais , Oxirredução , Óxidos
15.
Front Microbiol ; 13: 840562, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369425

RESUMO

Antibiotic resistance is one of the most important environmental challenges. Microalgae has been considered as a promising green media for environmental purification. In this work, sulfadimethoxine (SDM) biodegradation potential of Chlorella sp. L38 and Phaeodactylum tricornutum MASCC-0025 is investigated. Experimental results indicated that the tested freshwater and marine microalgae strains presented stress response to SDM addition. For Chlorella sp. L38, it has a good adaptability to SDM condition via antioxidant enzyme secretion (SOD, MDA, and CAT up to 23.27 U/mg, 21.99 µmol/g, and 0.31 nmol/min/mg) with removal rate around 88%. P. tricornutum MASCC-0025 exhibited 100% removal of 0.5 mg/L SDM. With increasing salinity (adding a certain amount of NaCl) of cultivation media, the removal rate of SDM by microalgae increased. Although its adaptive process was slower than Chlorella sp. L38, the salinity advantage would facilitate enzyme accumulation. It indicated that microalgae could be used to remove SDM from freshwater and marine environment via suitable microalgae strain screening.

16.
Environ Sci Technol ; 56(3): 1905-1916, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34856794

RESUMO

The development of highly efficient and stable monolithic catalysts is essential for the removal of volatile organic compounds (VOCs). Copper foam (CF) is a potential ideal carrier for monolithic catalysts, but its low surface area is not conducive to dispersion of active species, thus reducing the interface interaction with active species. Herein, a vertically oriented Cu(OH)2 nanorod was in situ grown on the CF, which acted as the template and precursor to synthesize CoCu-MOF. The optimized catalyst (12CoCu-R) delivers excellent performance for acetone oxidation with a T90 of 195 °C. Impressively, the catalyst demonstrated satisfactory stability in long-term, cycle, water resistance, and high airspeed tests. Therefore, the present study provides a novel strategy for rationally designing efficient monolithic catalysts for VOC oxidation and other environmental applications.

17.
Sci Total Environ ; 801: 149791, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34467899

RESUMO

CO2 absorption and microalgae conversion (CAMC) hybrid system is a promising alternative for simultaneous carbon capture and utilization. It can not only overcome the challenge of high energy consumption solvent thermal regeneration in chemical CO2 absorption, but also enhance the carbon conversion efficiency in biological conversion process. However, the discordance between CO2 absorption and bio-conversion rate has become the key to limiting the development of CAMC system. Therefore, in this study, low temperature plasma (LTP) mutation breeding technology was used to training Chlorella strains by combining undirected mutagenesis and directional screening. Then, the mutagenic microalgae were cultivated and evaluated in CAMC system. It was found that compared with original Chlorella L166, the OD680 of mutant strain L166-M3 in CAMC system increased 7.8%, and the maximum specific growth rate improved 27.5%. The carbon sequestration rate of wild Chlorella L166 increased from 82.9% to 93.7% after mutation treatment, the activity of RubisCO, and the content of NADPH produced by photoreaction increased 37.2% and 17.2%. In addition, lipid production of L166-M3 increased to 6.89 mg/L, which was 15.4% higher than original Chlorella L166. It could be observed that LTP mutation breeding could be used as a potential method for training algae species and improve the overall performance of CAMC system.


Assuntos
Chlorella , Microalgas , Biomassa , Dióxido de Carbono , Melhoramento Vegetal , Temperatura
18.
Drug Des Devel Ther ; 15: 3735-3747, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511883

RESUMO

PURPOSE: Oxidative stress-induced chondrocyte apoptosis and extracellular matrix (ECM) degradation plays an important role in the progression of osteoarthritis (OA). Bardoxolone methyl (BM), a semisynthetic triterpenoid, exerts strong effect against oxidative stress. The purpose of the present study was to determine the effectiveness of bardoxolone-methyl (BM) in preventing oxidative stress-induced chondrocyte apoptosis and extracellular ECM degradation in vitro and the role of alleviating OA progression in vivo. METHODS: Oxidative damage was induced by 25 mM tert-butyl hydroperoxide (TBHP) for 24 h in rat chondrocytes. 0.025 and 0.05 µM bardoxolone-methyl (BM) were used in vitro treatment. Ex-vivo cartilage explant model was established to evaluate the effect of BM on oxidative stress-induced ECM degradation. The mouse OA model was induced by surgical destabilization of the medial meniscus. RESULTS: In vitro, 0.025 and 0.05 µM BM reduced TBHP-induced excessive ROS generation, improved cell viability, increased malondialdehyde level and decreased superoxide dismutase level. 0.025 and 0.05 µM BM prevented TBHP-induced mitochondrial damage and apoptosis in chondrocytes BM activated heme oxygenase-1 (HO-1)/NADPH quinone oxidoreductase 1 (NOQ1) signaling pathway through targeting nuclear factor erythroid derived-2-related factor 2 (Nrf2). Additionally, BM treatment enhanced the expression levels of aggrecan and collagen II and inhibited the expression levels of matrix metalloproteinase 9 (MMP 9), MMP 13, Bax and cleaved-caspase-3. BM increased proteoglycan staining area and IOD value in ex vivo cultured experiment cartilage explants and improved the OARSI score, stands, max contact mean intensity, print area and duty cycle in mouse OA model. CONCLUSION: BM prevented oxidative stress-induced chondrocyte apoptosis and ECM degradation in vitro and alleviated OA in vivo, suggesting that BM serves as an effective drug for treatment with OA.


Assuntos
Artrite Experimental/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Osteoartrite/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Artrite Experimental/patologia , Cartilagem/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Relação Dose-Resposta a Droga , Matriz Extracelular/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ácido Oleanólico/administração & dosagem , Ácido Oleanólico/farmacologia , Osteoartrite/patologia , Ratos , Ratos Sprague-Dawley
19.
3 Biotech ; 11(6): 283, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34094802

RESUMO

A new deep-sea-derived actinomycete 12A22 was isolated from the sediment of the South China Sea which showed potential cytotoxic and antimicrobial activities. The actinomycete was identified as Actinoalloteichus cyanogriseus by investigating morphological characteristics and phylogenetic analyses based on its 16S rRNA gene sequence. Two compounds, cyclo-(L-Pro-D-Pro-L-Tyr-L-Tyr) (1) and 2-hydroxyethyl-3-methyl-1,4-naphthoquinone (2), were isolated and characterized from the fermentation broth of the strain 12A22. Compound 2 exhibited significant inhibitory activities against a variety of phytopathogenic fungi (Fusarium oxysporum f. sp. cucumerinum, Setosphaeria turcica, and Botrytis cinerea) and Gram-positive bacterium (Bacillus subtilis). In particular, this compound showed better antifungal activity against Botrytis cinerea than positive control amphotericin B. Besides, compound 2 showed moderate cytotoxic activity against human breast cancer MDA-MB-435 cells with IC50 10.59 µM, weaker than the positive control diaminedichloroplatinum with 5.91 µM. Our results suggested that this naphthoquinone could be used as a potential antimicrobial and antitumor agent. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02846-0.

20.
J Environ Sci (China) ; 105: 184-203, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34130835

RESUMO

Volatile organic compounds (VOCs) with high toxicity and carcinogenicity are emitted from kinds of industries, which endanger human health and the environment. Adsorption is a promising method for the treatment of VOCs due to its low cost and high efficiency. In recent years, activated carbons, zeolites, and mesoporous materials are widely used to remove VOCs because of their high specific surface area and abundant porosity. However, the hydrophilic nature and low desorption rate of those materials limit their commercial application. Furthermore, the adsorption capacities of VOCs still need to be improved. Porous organic polymers (POPs) with extremely high porosity, structural diversity, and hydrophobic have been considered as one of the most promising candidates for VOCs adsorption. This review generalized the superiority of POPs for VOCs adsorption compared to other porous materials and summarized the studies of VOCs adsorption on different types of POPs. Moreover, the mechanism of competitive adsorption between water and VOCs on the POPs was discussed. Finally, a concise outlook for utilizing POPs for VOCs adsorption was discussed, noting areas in which further work is needed to develop the next-generation POPs for practical applications.


Assuntos
Compostos Orgânicos Voláteis , Adsorção , Carvão Vegetal , Humanos , Polímeros , Porosidade
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