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1.
Nanotechnology ; 35(9)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37995375

RESUMO

Polyethylene glycol (PEG) is widely used as a phase change material (PCM) in thermal energy storage systems due to its high latent heat and chemical stability. However, practical application has been hindered by its low thermal conductivity and leakage issues. Therefore, developing shape-stable high thermal conductivity PCM is of great importance. In this study, new shape-stable composite PCM with high thermal conductivity and leak-prevention capabilities were designed. The porous carbon skeleton of diamond foam (DF) and dual-3D carbon nanotube-diamond foam (CDF) were prepared using the microwave plasma chemical vapor deposition method. The composite materials (DF/PEG and CDF/PEG) were produced by vacuum impregnation with PEG and skeletons. The results showed that CDF/PEG had the highest thermal conductivity, measuring 2.30 W·m-1·K-1, which is 707% higher than that of pure PEG. The employing of 3D networks of CNTs, which can improve the phonon mean free path in DF/PEG (1.79 W·m-1·K-1) while reducing phonon dispersion.The phonon vibration of dual-3D CDF plays an important role in heat transfer. PEG was physically absorbed and well-distributed in CDF, alleviating leakage of liquid PEG. The weight loss of CDF/PEG was only 25% at 70 °C for 120 s. Using CDF is an attractive and efficient strategy to increase the heat transfer of PEG and improve heat storage efficiency, alleviate the problem of poor shape-stability.

2.
J Integr Plant Biol ; 65(10): 2380-2394, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37534615

RESUMO

Mitogen-activated protein kinase (MAPK) cascades play pivotal roles in plant defense against phytopathogens downstream of immune receptor complexes. The amplitude and duration of MAPK activation must be strictly controlled, but the underlying mechanism remains unclear. Here, we identified Arabidopsis CPL1 (C-terminal domain phosphatase-like 1) as a negative regulator of microbe-associated molecular pattern (MAMP)-triggered immunity via a forward-genetic screen. Disruption of CPL1 significantly enhanced plant resistance to Pseudomonas pathogens induced by the bacterial peptide flg22. Furthermore, flg22-induced MPK3/MPK4/MPK6 phosphorylation was dramatically elevated in cpl1 mutants but severely impaired in CPL1 overexpression lines, suggesting that CPL1 might interfere with flg22-induced MAPK activation. Indeed, CPL1 directly interacted with MPK3 and MPK6, as well as the upstream MKK4 and MKK5. A firefly luciferase-based complementation assay indicated that the interaction between MKK4/MKK5 and MPK3/MPK6 was significantly reduced in the presence of CPL1. These results suggest that CPL1 plays a novel regulatory role in suppressing MAMP-induced MAPK cascade activation and MAMP-triggered immunity to bacterial pathogens.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas Quinases Ativadas por Mitógeno/genética , Arabidopsis/metabolismo , RNA Polimerase II/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas de Arabidopsis/metabolismo , Monoéster Fosfórico Hidrolases/genética , Regulação da Expressão Gênica de Plantas , Imunidade Vegetal/genética , Fosfoproteínas Fosfatases/genética , Fatores de Transcrição/metabolismo , Proteínas de Ligação a RNA/metabolismo
3.
Int Immunopharmacol ; 123: 110736, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549513

RESUMO

AIMS: Doxorubicin (DOX) is an effective anti-tumor drug, but the cardiotoxicity severely limits its clinical use. Interestingly, a hypothesis has emerged suggesting an association between DOX-induced cardiotoxicity and mitochondrial disorders and oxidative stress. The mitochonic acid 5 (MA5) shows promise in alleviating mitochondrial dysfunction by promoting mitochondrial ATP synthesis and reducing reactive oxygen species (ROS) accumulation, though its potential in ameliorating DOX-induced cardiotoxicity remains elusive. METHODS: Network pharmacology approach, molecular docking techniques, and molecular dynamics simulation (MDS) were used to reveal the specific drug targets and pharmaceutical mechanisms involved in the treatment of DOX-induced cardiotoxicity using MA5. For experimental verification, cardiomyocytes (H9c2) and mice were exposed to DOX in the presence or absence of MA5. Our investigation involved the assessment of echocardiographic parameters, cardiac enzymes, inflammatory factors, mitochondrial function, myocardial structure, and cardiomyocyte pyroptosis. RESULTS: Among the 100 core targets identified in network pharmacology, MA5 was pharmacologically active against DOX-induced cardiotoxicity via pathways implicated in cancer, prostate cancer, lipids and atherosclerosis. Molecular docking analysis confirmed that MA5 docked well with TNF-α, interleukin-6 (IL-6), and caspase-3. Furthermore, MA5 exhibited a stronger affinity toward TNF-α than IL-6 and caspase-3. Subsequent MDS revealed the stability of binding between MA5 and TNF-α. The DOX-challenged mice also displayed abnormal myocardial enzymogram, disrupted systolic and diastolic function, and elevated inflammation and cardiomyocyte pyroptosis, which could be mitigated by the administration of MA5. Similarly, H9c2 cells exposed to DOX showed increased intracellular ROS production and impaired mitochondrial function, which were relieved by MA5 treatment. CONCLUSION: Our findings suggest that MA5 attenuates DOX-induced cardiac anomalies through the TNF-α-mediated regulation of inflammation and pyroptosis. These insights offer a potential therapeutic strategy for managing DOX-induced cardiac complications, thereby improving the safety and efficacy of cancer treatments.


Assuntos
Miócitos Cardíacos , NF-kappa B , Masculino , Camundongos , Animais , NF-kappa B/metabolismo , Miócitos Cardíacos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Piroptose , Caspase 3/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Interleucina-6/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Simulação de Acoplamento Molecular , Doxorrubicina/efeitos adversos , Estresse Oxidativo , Inflamação/metabolismo , Apoptose
4.
Front Plant Sci ; 14: 1096831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342142

RESUMO

Sclerotinia sclerotiorum, the causal agent of Sclerotinia stem rot (SSR) on more than 450 plant species, is a notorious fungal pathogen. Nitrate reductase (NR) is required for nitrate assimilation that mediates the reduction of nitrate to nitrite and is the major enzymatic source for NO production in fungi. To explore the possible effects of nitrate reductase SsNR on the development, stress response, and virulence of S. sclerotiorum, RNA interference (RNAi) of SsNR was performed. The results showed that SsNR-silenced mutants showed abnormity in mycelia growth, sclerotia formation, infection cushion formation, reduced virulence on rapeseed and soybean with decreased oxalic acid production. Furthermore SsNR-silenced mutants are more sensitive to abiotic stresses such as Congo Red, SDS, H2O2, and NaCl. Importantly, the expression levels of pathogenicity-related genes SsGgt1, SsSac1, and SsSmk3 are down-regulated in SsNR-silenced mutants, while SsCyp is up-regulated. In summary, phenotypic changes in the gene silenced mutants indicate that SsNR plays important roles in the mycelia growth, sclerotia development, stress response and fungal virulence of S. sclerotiorum.

5.
Fitoterapia ; 165: 105393, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36528150

RESUMO

Four novel iridoid glycosides neocornuside E-H (1-4), together with nine known ones (5-13), were isolated from fruits of Cornus officinalis. Their chemical structures were determined on the basis of spectroscopic analyses and comparing of the literature data. All of the isolated compounds were evaluated for their antidiabetic activity in insulin resistant HepG2 cells. Compounds 2, 4, 5, 8, and 12 exhibited antidiabetic activities with EC50 values of 40.12, 2.54, 70.43, 15.31, and 4.86 µM, respectively. Flow Sight cytometry analysis indicated that compounds 2, 4, 5, 8, and 12 improved the ability of 2-NBDG uptake of insulin-induced HepG2 cells.


Assuntos
Cornus , Glicosídeos Iridoides , Glicosídeos Iridoides/farmacologia , Glicosídeos Iridoides/química , Hipoglicemiantes/farmacologia , Cornus/química , Frutas/química , Estrutura Molecular , Insulina , Glicosídeos/química
6.
Molecules ; 27(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35897906

RESUMO

Four previously undescribed iridoid glycosides neocornuside A-D (1-4), along with six known ones (5-10), were isolated from Cornus officinalis fruit. Their structures were elucidated by extensive spectroscopic (NMR, UV, IR, and MS) analysis and comparison with data reported in the literature. All isolates were assessed for their antidiabetic activity on the relative glucose consumption in insulin-induced insulin-resistant HepG2 cells. The results showed that compounds 1, 3, and 7 exhibited significant antidiabetic activities with EC50 values of 0.582, 1.275, and 0.742 µM, respectively. Moreover, compounds 1, 3, and 7 could improve the ability of 2-NBDG uptake of insulin-induced HepG2 cells.


Assuntos
Cornus , Insulinas , Cornus/química , Frutas/química , Glicosídeos/química , Hipoglicemiantes/análise , Hipoglicemiantes/farmacologia , Insulinas/análise , Glicosídeos Iridoides/química
7.
Phytochemistry ; 202: 113314, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35810878

RESUMO

Epimesatines A-I, nine undescribed prenylated flavonoids, along with ten known analogues, were isolated from the aerial parts of Epimedium sagittatum Maxim. The structures and absolute configurations of epimesatines A-I were determined using a combination of spectroscopic data, Rh2(OCOCF3)4-induced electronic circular dichroism (ECD) experiments, ECD comparisons, and X-ray crystallography analysis. Epimesatines A and I displayed notable activities on the viabilities of human non-small cell lung cancer (NSCLC) A549 cells with IC50 values of 1.77 and 9.97 µM, respectively. Furthermore, epimesatines A and I significantly inhibited the expression of sphingosine kinase 1 (SPHK1) in A549 cells. In addition, none of these compounds showed obvious toxicity on normal human lung bronchial epithelial BEAS-2B cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Epimedium , Neoplasias Pulmonares , Epimedium/química , Epimedium/metabolismo , Flavonoides/química , Humanos , Fosfotransferases (Aceptor do Grupo Álcool)
8.
Phytochemistry ; 200: 113230, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35568259

RESUMO

Seven undescribed lignans, equiselignan A-F, and six undescribed terpenoids, equiseterpenoid A-E (including two pairs of enantiomers, (+/-)-equiselignan A and (+/-)-equiseterpenoid E), were isolated from the stems of Ephedra equisetina Bunge. Their structures were elucidated by spectroscopic methods, and the absolute configurations of the undescribed compounds were determined by interpretation of their electronic circular dichroic (ECD) and optical rotation data. In ß-hexosaminidase (ß-Hex) release assay, anti-asthmatic activities of all of the compounds were evaluated by releasing ß-Hex in C48/80-induced RBL-2H3 cells. The ß-Hex release rates of equiselignan B and equiseterpenoid B were 0.86 ± 0.094 and 0.86 ± 0.012 by comparing with model group, whereupon equiselignan B and equiseterpenoid B exhibited significant anti-asthmatic activities.


Assuntos
Antiasmáticos , Ephedra , Lignanas , Ephedra/química , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Estereoisomerismo , Terpenos/farmacologia
9.
Plant Cell ; 34(8): 3088-3109, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35639755

RESUMO

Rice false smut caused by Ustilaginoidea virens is emerging as a devastating disease of rice (Oryza sativa) worldwide; however, the molecular mechanisms underlying U. virens virulence and pathogenicity remain largely unknown. Here we demonstrate that the small cysteine-rich secreted protein SCRE6 in U. virens is translocated into host cells during infection as a virulence factor. Knockout of SCRE6 leads to attenuated U. virens virulence to rice. SCRE6 and its homologs in U. virens function as a novel family of mitogen-activated protein kinase phosphatases harboring no canonical phosphatase motif. SCRE6 interacts with and dephosphorylates the negative immune regulator OsMPK6 in rice, thus enhancing its stability and suppressing plant immunity. Ectopic expression of SCRE6 in transgenic rice promotes pathogen infection by suppressing the host immune responses. Our results reveal a previously unidentified fungal infection strategy in which the pathogen deploys a family of tyrosine phosphatases to stabilize a negative immune regulator in the host plant to facilitate its infection.


Assuntos
Oryza , Doenças das Plantas , Interações Hospedeiro-Patógeno/genética , Hypocreales , Oryza/genética , Oryza/microbiologia , Monoéster Fosfórico Hidrolases/genética , Doenças das Plantas/microbiologia , Imunidade Vegetal/genética
10.
J Asian Nat Prod Res ; : 1-7, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35611800

RESUMO

Two new cyclotrypyamine alkaloids equisetinines A and B, as well as three known alkaloids (3-5) were isolated from the stems of Ephedra equisetina Bunge. Their structures were characterized by spectroscopic methods, and the absolute configurations of the new compounds were determined by interpretation of their electronic circular dichroism. Anti-asthmatic activities of compounds were evaluated by releasing ß-Hex in C48/80-induced RBL-2H3 cells, and compound 5 exhibited significant anti-asthmatic activities.

11.
Sci Total Environ ; 820: 153267, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35074368

RESUMO

Cyanobacterial blooms are increasingly threatening the aquatic ecosystem functioning as a result of the global warming and eutrophication. The "top-down" control of cyanobacteria from consumers like the protozoans shows great potential because of the effectiveness and environment-friendliness. To reveal how the nutrition availability and elevated temperature affect the cyanobacteria removal through protozoans grazing, we grew the toxic Microcystis aeruginosa and the mixotrophic Ochromonas gloeopara in monocultures and cocultures at environmentally relevant nitrogen levels (0.5-8.0 mg L-1) under 25 °C and 30 °C, respectively. The growth of M. aeruginosa in monocultures was significantly enhanced as nitrogen concentration and temperature rose, partially benefitting from the promoted photosynthesis. By contrast, nitrogen availability affected neither the photoautotrophic growth nor the feeding on Microcystis of the mixotrophic O. gloeopara, but high temperature induced the mixotroph to be more heterotrophic as evidenced by the suppressed photosynthesis but strengthened feeding activity. Accordingly, the M. aeruginosa removal through O. gloeopara grazing in cocultures was delayed with increasing nitrogen, which, however, was sharply accelerated by elevated temperature. Based on the Gaussian models fitting, the theoretical time that the Microcystis was removed at 25 °C was prolonged from about 7.5 days to 10 days with increased nitrogen, but it was reduced to less than 4.6 days in all groups at 30 °C. While the intensity of Microcystis blooms is strongly positively correlated to the nutrition availability and temperature, the present study provided references for the practical application of Microcystis removal through grazing outdoors.


Assuntos
Microcystis , Ochromonas , Ecossistema , Microcistinas , Nitrogênio , Temperatura
12.
PLoS One ; 16(12): e0260977, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34882717

RESUMO

Ramp metering on freeway is one of the effective methods to alleviate traffic congestion. This paper advances the field of freeway ramp metering by introducing an application to the on-ramp, capitalizing on the macro traffic follow theory and improved the freeway traffic flow. The Particle Swarm Optimization (PSO) based on Proportional Integral Derivative (PID) controller is further developed to single ramp metering as well as to optimize the PID parameters. The approach is applied to a case study of the Changyi Freeway(G5513) in Hunan, China. The simulation is conducted by applying the actual profile traffic data to PID controller to adjust the entering traffic flow on the freeway on-ramp. The results show that the PSO-PID controller tends to converge in about 80 minutes, and the density tends to be stable after 240 iterations. The system has smaller oscillation, more accurate adjustment of ramp regulation rate, and more ideal expected traffic flow density. The traffic congestion on mainline is effectively slowed down, traffic efficiency is improved, and travel time and cost are reduced. The nonlinear processing ability of PSO-PID controller overcomes the defects of the traditional manual closing ramp, and can be successfully applied in the field of intelligent ramp metering.


Assuntos
Acidentes de Trânsito/prevenção & controle , Algoritmos , Condução de Veículo/estatística & dados numéricos , Simulação por Computador , Humanos , Segurança
13.
Mol Med Rep ; 24(5)2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34498705

RESUMO

Tubular atrophy/interstitial fibrosis (TA/IF) is a major cause of late allograft loss, and inflammation within areas of TA/IF is associated with adverse outcomes in kidney transplantation. However, there is currently no satisfactory method to suppress this inflammation to improve TA/IF. The present study aimed to determine the proinflammatory role of receptor­interacting protein 3 (RIP3) in TA/IF to discover a novel therapeutic target. Reverse transcription­quantitative PCR and western blotting were performed to detect the expression of RIP3 and inflammation­associated factors. Lactate dehydrogenase release assay was used to determine necroptosis. Fluorescent 2,7­dichlorodihydrofluorescein diacetate was used to detect the levels of reactive oxygen species (ROS). The results demonstrated that patients with chronic TA/IF exhibited upregulated receptor­interacting protein 3 (RIP3) expression compared with the patients who had a favorable recovery after renal transplant. Therefore, the current study used normal renal tubular epithelial cells HK­2 to establish a cellular model with a high expression level of RIP3 in order to investigate the effect of RIP3 on renal epithelial cells after transplantation. The western blotting results demonstrated that overexpression of RIP3 could significantly increase the phosphorylation level of the necroptosis executive molecule mixed lineage kinase domain­like protein. Lactate dehydrogenase release, a key feature of necroptosis, was also markedly improved by RIP3 overexpression. Moreover, a higher inflammatory response was detected in HK­2 cells with RIP3 overexpression, and this elevated inflammation could be restored by the necroptosis inhibitor necrosulfonamide. Of note, it was found that overexpression of RIP3 activated the NF­κB signaling pathway via the excessive accumulation of ROS to induce necroptosis, which ultimately led to inflammation. Collectively, these findings indicated that overexpression of RIP3 promoted necroptosis via a ROS­dependent NF­κB pathway to induce chronic inflammation, suggesting that RIP3 may have the potential to be a therapeutic target against inflammation in TA/IF.


Assuntos
Inflamação/metabolismo , Nefropatias/metabolismo , Túbulos Renais/patologia , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Adulto , Atrofia/etiologia , Atrofia/metabolismo , Atrofia/patologia , Estudos de Casos e Controles , Feminino , Fibrose/etiologia , Fibrose/metabolismo , Fibrose/patologia , Humanos , Inflamação/etiologia , Inflamação/patologia , Nefropatias/etiologia , Nefropatias/patologia , Túbulos Renais/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/genética , Necroptose/fisiologia , Fosforilação , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais
14.
Iran J Public Health ; 50(5): 908-918, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34183949

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) have recently shown promise for the treatment of various types of chronic kidney disease models. However, the mechanism of this effect is still not well understood. Our study is aimed to investigate the effect of MSCs on transforming growth factor beta 1 (TGF-ß1)-induced epithelial mesenchymal transition (EMT) in renal tubular epithelial cells (HK-2 cells) and the underlying mechanism related to the reciprocal balance between hepatocyte growth factor (HGF) and TGF-ß1. METHODS: Our study was performed at Ningbo University, Ningbo, Zhejiang, China between Mar 2017 and Jun 2018. HK-2 cells were initially treated with TGF-ß1, then co-cultured with MSCs. The induced EMT was assessed by cellular morphology and the expressions of alpha-smooth muscle actin (α-SMA) and EMT-related proteins. MTS assay and flow cytometry were employed to detect the effect of TGF-ß1 and MSCs on HK-2 cell proliferation and apoptosis. SiRNA against hepatocyte growth factor (siHGF) was transfected to decrease the expression of HGF to identify the role of HGF in MSCs inhibiting HK-2 cells EMT. RESULTS: Overexpressing TGF-ß1 decreased HGF expression, induced EMT, suppressed proliferation and promoted apoptosis in HK-2 cells; but when co-cultured with MSCs all the outcomes were reversed. However, after treated with siHGF, all the benefits taken from MSCs vanished. CONCLUSION: TGF-ß1 was a motivating factor of kidney cell EMT and it suppressed the HGF expression. However, MSCs provided protection against EMT by increasing HGF level and decreasing TGF-ß1 level. Our results also demonstrated HGF is one of the critical factor in MSCs anti- fibrosis.

15.
Environ Pollut ; 278: 116918, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33743270

RESUMO

Many prey organisms adaptively respond to predation risk by inducible defenses with underlying tradeoffs in resource allocation. Cyanobacterial blooms expose zooplankton to poor food conditions, affecting the herbivores' fitness. Given the interferences on resources allocation and life history traits, poor-quality cyanobacteria are predicted to affect the adaptive predator-induced responses in zooplankton. Here, we exposed two clones (i.e., clones SH and ZJ) of the cladoceran Daphnia mitsukuri to different combinations of fish predation cues and diets containing toxic Microcystis aeruginosa (0%-30%). D. mitsukuri matured at a small size and had elongated relative tail spine as adaptive responses to fish cues. Despite the comparable tail spine defense, fish cue-induced changes in growth and reproduction in the clone SH were more pronounced than those in the clone ZJ under no M. aeruginosa. Animals accumulated microcystin in the whole body with increasing abundance of M. aeruginosa. However, the inducible enhanced tail spine allometry was not affected, resulting in unchanged tail spine defense by Daphnia under all M. aeruginosa treatments. By contrast, M. aeruginosa remarkably decreased the adaptive maturation size and the offspring number in all animals. However, the inducible reproductive effort tended to increase or remain unchanged depending on clones associated with the constant or decreased responses of the somatic growth effort under increasing M. aeruginosa. Our results suggested that toxic M. aeruginosa did not alter the resource allocation to antipredator morphological defense but affected the somatic growth and reproduction in D. mitsukuri under fish cues. The present study highlights the different effects of toxic cyanobacteria on adaptive predator-induced responses in zooplankton, promoting the understanding for the morphological defense-mediated predator-prey interactions in eutrophic environments.


Assuntos
Microcystis , Animais , Sinais (Psicologia) , Daphnia , Comportamento Predatório , Alocação de Recursos
16.
Environ Pollut ; 273: 116496, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33484999

RESUMO

Cadmium (Cd) is one of the predominant anthropogenic pollutants in aquatic systems. As Cd has negative effects on species at all trophic levels, the community composition in aquatic habitats can be changed as a result of Cd stress. The response of mixotrophic protists to environmental stressors is particularly important as they act as both producers and consumers in complex planktonic communities. In this study, we used mixotrophic Ochromonas gloeopara to study its growth and photosynthetic responses to Cd, and specially focused on the effects of initial Cd concentrations and nutrient levels on its capacity to remove Cd. Results showed that when Cd concentration reached 0.5 mg L-1, the growth rate and carrying capacity were significantly inhibited, whereas the photosynthesis was markedly decreased when Cd concentration reached 0.15 mg L-1. Moreover, under Cd concentration 0.15, 0.5, 0.9, 1.6, and 2.0 mg L-1, the removal efficiencies of Cd by O. gloeopara were 83.2%, 77.7%, 74.6%, 70.1%, and 68.8%, respectively. The increase of nitrogen did not cause significant effect on the removal capacity of Cd by O. gloeopara, but increased concentration of phosphorus significantly enhanced the removal capacity of Cd. Our findings indicated that the mixotrophic O. gloeopara has strong tolerance and capacity to remove Cd, and increasing concentration of phosphorus can increase its removal capacity, suggesting that O. gloeopara has great potential application value in mitigating Cd pollution in waters.

17.
Chemosphere ; 272: 129645, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33465615

RESUMO

The solar ultraviolet-B radiation (UVB) is increasingly affecting the aquatic ecosystems due to the long-term antropic damage to the stratospheric ozone. The distrupted interspecies competition is one of the primary causes driving the plankton community composition shifts under UVB stress. To reveal the competitive responses to enhanced UVB radiation, we grew two green algae Scenedesmus obliquus and Chlorella pyrenoidosa, and the unicellular cyanobacterium Microcystis aeruginosa in monocultures and in cocultures under differerent UVB intensities (0, 0.3 and 0.7 W m-2), respectively. Results showed that elevated UVB radiation consistently decreased the population carrying capacies and the photosynthesis of the three species in monocultures. While cocultivated, C. pyrenoidosa was competively excluded by the presence of S. obliquus, and the competitive outcome was not affected by UVB exposure. By contrast, unicellular M. aeruginosa overwhelmingly suppressed the population growth of S. obliquus under no UVB, yet S. obliquus tended to be a better competitor under 0.3-0.7 W m-2 UVB exposure. The species-specific photosynthesis sensitivity to UVB can partly explain the different tolerance of the algae to UVB and the change of competition outcome under elevated UVB. The present study elucidated the potential role of increased UVB radiation in determining the competitions between phytoplankton species, contributing to the understanding of phytoplankton community shifts under enhanced UVB stress.


Assuntos
Chlorella , Microcystis , Ecossistema , Fotossíntese , Dinâmica Populacional
18.
Materials (Basel) ; 12(15)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390738

RESUMO

In the present investigation, a nitrogen-doped multilayer homoepitaxial single crystal diamond is synthesized on a high-pressure high temperature (HPHT) Ib-type diamond substrate using the microwave plasma chemical vapor deposition (MPCVD) method. When 0.15 sccm of nitrogen was added in the gas phase, the growth rate of the doped layer was about 1.7 times that of the buffer layer, and large conical and pyramidal features are formed on the surface of the sample. Raman mapping and photoluminescence imaging of the polished cross sectional slice shows a broadband emission, with a characteristic zero phonon line (ZPL) at 575 nm in the doped layers, and large compressive stress was formed in the nitrogen-doped layers. X-ray topography shows that the defects at the interface can induce dislocation. The pyramid feature is formed at the defect, and more nitrogen-related defects are formed in the pyramid region. Thin nitrogen-doped multilayers were successfully prepared, and the thickness of the nitrogen-doped and buffer layers was about 650 nm each. The indentation measurements reveal that the thin nitrogen-doped multilayers are ultra-tough (at least ~22 MPa m1/2), compared to the Ib-type HPHT seed substrate (~8 MPa m1/2) and the unintentionally doped chemical vapor deposition (CVD) single crystal diamond (~14 MPa m1/2).

19.
Purinergic Signal ; 14(4): 359-369, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30084084

RESUMO

Painful diabetic neuropathy (PDN) is a common and troublesome diabetes complication. Protein kinase C (PKC)-mediated dorsal root ganglia (DRG) P2X3 receptor upregulation is one important mechanism underlying PDN. Accumulating evidence demonstrated that electroacupuncture (EA) at low frequency could effectively attenuate neuropathic pain. Our previous study showed that 2-Hz EA could relieve pain well in PDN. The study aimed to investigate whether 2-Hz EA relieves pain in PDN through suppressing PKC-mediated DRG P2X3 receptor upregulation. A 7-week feeding of high-fat and high-sugar diet plus a single injection of streptozotocin (STZ) in a dose of 35 mg/kg after a 5-week feeding of the diet successfully induced type 2 PDN in rats as revealed by the elevated body weight, fasting blood glucose, fasting insulin and insulin resistance, and the reduced paw withdrawal threshold (PWT), as well as the destructive ultrastructural change of sciatic nerve. DRG plasma membrane P2X3 receptor level and DRG PKC expression were elevated. Two-hertz EA failed to improve peripheral neuropathy; however, it reduced PWT, DRG plasma membrane P2X3 receptor level, and DRG PKC expression in PDN rats. Intraperitoneal administration of P2X3 receptor agonist αß-meATP or PKC activator phorbol 12-myristate 13-acetate (PMA) blocked 2-Hz EA analgesia. Furthermore, PMA administration increased DRG plasma membrane P2X3 receptor level in PDN rats subject to 2-Hz EA treatment. These findings together indicated that the analgesic effect of EA in PDN is mediated by suppressing PKC-dependent membrane P2X3 upregulation in DRG. EA at low frequency is a valuable approach for PDN control.


Assuntos
Gânglios Espinais/metabolismo , Neuralgia/metabolismo , Receptores de Quinase C Ativada/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Animais , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Ratos Sprague-Dawley , Receptores de Quinase C Ativada/efeitos dos fármacos , Receptores Purinérgicos P2X3/efeitos dos fármacos , Regulação para Cima
20.
Onco Targets Ther ; 11: 3267-3280, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910622

RESUMO

BACKGROUND: The vitamin D receptor (VDR) plays a key role in vitamin-mediated signaling pathway. Emerging evidence has suggested that the VDR polymorphism may contribute to the risk of prostate cancer (PCa). However, the existing results are not conclusive in Asian population. METHODS: We aim to evaluate the potential role of VDR polymorphisms on PCa of Asian population. PubMed, Scopus, Embase, Web of Science, Chinese National Knowledge Infrastructure, Wang Fang Data, and VIP Periodical were retrieved, and eligible studies (case-control or cohort study) meeting the inclusion criteria were evaluated through an updated meta-analysis using Stata13.0 software. RESULTS: A total of 1,363 cases and 2,101 controls obtained from 13 eligible publications were eventually included in this meta-analysis. Our results show that a significant association of VDR taq1 polymorphism with PCa risk, especially in the Japanese population. In the clinical stage-stratified analysis, the pooled results revealed no significant difference in genetic polymorphisms between the local stage and control groups, whereas there was increased frequency of T allele and TT genotype in the advanced tumor stage group compared with local tumor stage or control groups. Similarly, no significant difference was seen in Gleason <7 and control groups, but the T allele and TT genotype were significantly higher in the Gleason ≥7 group compared with Gleason <7 or control groups. CONCLUSION: The VDR TaqI polymorphism might be associated with PCa risk in Asian population, especially in the Japanese population. Also, PCa patients carrying the T allele or TT genotype were more likely to progress to advanced stage. These results suggest that VDR TaqI polymorphisms may be potential diagnostic biomarkers for PCa susceptibility.

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