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1.
Int J Phytoremediation ; : 1-10, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973396

RESUMO

Vesicular sequestration is a potential strategy for enhancing plant tolerance to cadmium (Cd) and arsenic (As). In this study, the ectopic overexpression of yeast-derived ScSMF2 in Arabidopsis thaliana was found to enhance the accumulation and tolerance of Cd and As in transgenic plants. ScSMF2 was localized on vacuole membranes and formed puncta structures in plant cells when agro-infiltrated for transient expression. Transgenic Arabidopsis showed less retardation on root elongation and shoot weight and more accumulation of Cd, As (III) and As (V) when cultured on medium containing Cd or As. Overexpression of ScSMF2 promoted accumulation of Cd and arsenic in transgenic Arabidopsis, which were over twice higher than in WT plants when cultured in soil. This study provides insights into the mechanisms involved in the vesicular sequestration of heavy metals in plant and presents a potential strategy for enhancing the phytoremediation capacity of plants toward heavy metals.


Ectopic overexpression of the yeast Mn2+ transporter SMF2 in Arabidopsis thaliana substantially boosts the accumulation and tolerance to Cd and As in plants. This augmentation is attributed to the enhanced efficacy of intracellular vesicle sequestration, thereby bolstering the capacity of plants to sequester and detoxify these toxic heavy metals. This investigation introduces a potential approach for cultivating plants with improved phytoremediation capabilities, thereby advancing eco-friendly and sustainable remediation initiatives against heavy metal pollution.

2.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791210

RESUMO

Functional microexons have not previously been described in filamentous fungi. Here, we describe a novel mechanism of transcriptional regulation in Trichoderma requiring the inclusion of a microexon from the Xlr2 gene. In low-glucose environments, a long mRNA including the microexon encodes a protein with a GAL4-like DNA-binding domain (Xlr2-α), whereas in high-glucose environments, a short mRNA that is produced encodes a protein lacking this DNA-binding domain (Xlr2-ß). Interestingly, the protein isoforms differ in their impact on cellulase and xylanase activity. Deleting the Xlr2 gene reduced both xylanase and cellulase activity and growth on different carbon sources, such as carboxymethylcellulose, xylan, glucose, and arabinose. The overexpression of either Xlr2-α or Xlr2-ß in T. virens showed that the short isoform (Xlr2-ß) caused higher xylanase activity than the wild types or the long isoform (Xlr2-α). Conversely, cellulase activity did not increase when overexpressing Xlr2-ß but was increased with the overexpression of Xlr2-α. This is the first report of a novel transcriptional regulation mechanism of plant-cell-wall-degrading enzyme activity in T. virens. This involves the differential expression of a microexon from a gene encoding a transcriptional regulator.


Assuntos
Celulases , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Trichoderma , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Trichoderma/genética , Trichoderma/metabolismo , Trichoderma/enzimologia , Celulases/metabolismo , Celulases/genética , Endo-1,4-beta-Xilanases/metabolismo , Endo-1,4-beta-Xilanases/genética , Parede Celular/metabolismo , Açúcares/metabolismo
3.
Neuroimage ; 282: 120398, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37778420

RESUMO

Magnetic Resonance Imaging (MRI) is widely applied in medical diagnosis due to its excellent non-invasiveness. With the increasing intensity of static magnetic field (SMF), the safety assessment of MRI has been ongoing. In this study, zebrafish larvae were exposed to SMFs of 0.4, 3.0, and 9.4 T for 2 h (h), and we found that there was no significant difference in the number of spontaneous tail swings, heart rate, and body length of zebrafish larvae in the treatment groups. The expression of development-related genes shha, pygo1, mylz3 and runx2b in the three SMF groups was almost not significantly different from the control group. Behavior tests unveiled a notable reduction in both the average speed and duration of high-speed movements in zebrafish larvae across all three SMF groups. In addition, the 0.4 and 3.0 T SMFs increased the migration of neutrophils in caudal fin injury, and the expression of pro-inflammatory cytokines was also increased. To explore the mechanism of SMFs on zebrafish immune function, this study utilized aanat2-/- mutant fish to demonstrate the effect of melatonin (MT) involvement in SMFs on zebrafish immune function. This study provides experimental data for understanding the effects of SMFs on organisms, and also provides a new insight for exploring the relationship between magnetic fields and immune function.


Assuntos
Campos Magnéticos , Peixe-Zebra , Animais , Imunidade
4.
Prep Biochem Biotechnol ; 53(9): 1013-1042, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37651735

RESUMO

Microbial surfactants are green molecules with high surface activities having the most promising advantages over chemical surfactants including their ability to efficiently reducing surface and interfacial tension, nontoxic emulsion-based formulations, biocompatibility, biodegradability, simplicity of preparation from low cost materials such as residual by-products and renewable resources at large scales, effectiveness and stabilization under extreme conditions and broad spectrum antagonism of pathogens to be part of the biocontrol strategy. Thus, biosurfactants are universal tools of great current interest. The present work describes the major types and microbial origin of surfactants and their production optimization from agro-industrial wastes in the batch shake-flasks and bioreactor systems through solid-state and submerged fermentation industries. Various downstream strategies that had been developed to extract and purify biosurfactants are discussed. Further, the physicochemical properties and functional characteristics of biosurfactants open new future prospects for the development of efficient and eco-friendly commercially successful biotechnological product compounds with diverse potential applications in environment, industry, biomedicine, nanotechnology and energy-saving technology as well.


HighlightsBiosurfactants are important biotechnological products with unique superior potentials over their synthetic counterparts.Physiological roles of biosurfactants in survival of the producing microorganisms under unfavorable conditions.Classification of biosurfactants.Biosurfactant types produced by yeasts, fungi and bacteria.Production efficiency optimization of biosurfactants.Utilization of agro-industrial wastes as economic renewable substrates for biosurfactants production.Production of biosurfactants by solid-state and submerged fermentation industries.Potential applications of biosurfactants in environment.Glycolipid biosurfactants efficiently control pathogens causing their membrane disruption.Potential application of biosurfactants in the oil industry.Natural surfactants are novel capping and stabilizing agents for nanoparticles synthesis.

5.
Curr Genet ; 68(1): 125-141, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34761291

RESUMO

Cryptococcus neoformans, basidiomycetous pathogenic yeast, is basically an environmental fungus and, therefore, challenged by ever changing environments. In this study, we focused on how C. neoformans responds to stress caused by cadmium that is one of high-risk pollutants. By tracking phenotypes of the resistance or sensitivity to cadmium, we undertook forward and reverse genetic studies to identify genes involved in cadmium metabolism in C. neoformans. We found that the main route of Cd2+ influx is through Mn2+ ion transporter, Smf1, which is an ortholog of Nramp (natural resistance-associated macrophage protein 1) of mouse. We found that serotype A strains are generally more resistant to cadmium than serotype D strains and that cadmium resistance of H99, a representative of serotype A strains, was found to be due to a partial defect in SMF1. We found that calcium channel has a subsidiary role for cadmium uptake. We also showed that Pca1 (P-type-ATPase) functions as an extrusion pump for cadmium. We examined the effects of some metals on cadmium toxicity and suggested (i) that Ca2+ and Zn2+ could exert their protective function against Cd2+ via restoring cadmium-inhibited cellular processes and (ii) that Mg2+ and Mn2+ could have antagonistic roles in an unknown Smf1-independent Cd2+ uptake system. We proposed a model for Cd2+-response of C. neoformans, which will serve as a platform for understanding how this organism copes with the toxic metal.


Assuntos
Criptococose , Cryptococcus neoformans , Cádmio/toxicidade , Criptococose/microbiologia , Cryptococcus neoformans/genética
6.
J Magn Reson Imaging ; 56(2): 354-365, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34921571

RESUMO

BACKGROUND: Ultra-high field magnetic resonance imaging (MRI) has obvious advantages in acquiring high-resolution images. 7 T MRI has been clinically approved and 21.1 T MRI has also been tested on rodents. PURPOSE: To examine the effects of ultra-high field on mice behavior and neuron activity. STUDY TYPE: Prospective, animal model. ANIMAL MODEL: Ninety-eight healthy C57BL/6 mice and 18 depression model mice. FIELD STRENGTH: 11.1-33.0 T SMF (static magnetic field) for 1 hour and 7 T for 8 hours. Gradients were not on and no imaging sequence was used. ASSESSMENT: Open field test, elevated plus maze, three-chambered social test, Morris water maze, tail suspension test, sucrose preference test, blood routine, biochemistry examinations, enzyme-linked immunosorbent assay, immunofluorescent assay. STATISTICAL TESTS: The normality of the data was assessed by Shapiro-Wilk test, followed by Student's t test or the Mann-Whitney U test for statistical significance. The statistical cut-off line is P < 0.05. RESULTS: Compared to the sham group, healthy C57/6 mice spent more time in the center area (35.12 ± 4.034, increased by 47.19%) in open field test and improved novel index (0.6201 ± 0.02522, increased by 16.76%) in three-chambered social test a few weeks after 1 hour 11.1-33.0 T SMF exposure. 7 T SMF exposure for 8 hours alleviated the depression state of depression mice, including less immobile time in tail suspension test (58.32% reduction) and higher sucrose preference (increased by 8.80%). Brain tissue analysis shows that 11.1-33.0 T and 7 T SMFs can increase oxytocin by 164.65% and 36.03%, respectively. Moreover, the c-Fos level in hippocampus region was increased by 14.79%. DATA CONCLUSION: 11.1-33.0 T SMFs exposure for 1 hour or 7 T SMF exposure for 8 hours did not have detrimental effects on healthy or depressed mice. Instead, these ultra-high field SMFs have anti-depressive potentials. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 1.


Assuntos
Campos Magnéticos , Imageamento por Ressonância Magnética , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Estudos Prospectivos , Sacarose
7.
Arch Microbiol ; 205(1): 11, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36460824

RESUMO

Solid-state fermentation (SSF) is a type of fermentation process with potential to use agro-industrial by-products as a carbon source. Nonetheless, there are few studies evaluating SSF compared to submerged fermentation (SmF) to produce polyhydroxyalkanoates (PHAs). Different methodologies are available associating the two processes. In general, the studies employ a 1st step by SSF to hydrolyze the agro-industrial by-products used as a carbon source, and a 2nd step to produce PHA that can be carried out by SmF or SSF. This paper reviewed and compared the different methodologies described in the literature to assess their potential for use in PHA production. The studies evaluated showed that highest PHA yields (86.2% and 82.3%) were achieved by associating SSF and SmF by Cupriavidus necator. Meanwhile, in methodologies using only SSF, Bacillus produced the highest yields (62% and 56.8%). Since PHA (%) does not necessarily represent a higher production by biomass, the productivity parameter was also compared between studies. We observed that the highest productivity results did not necessarily represent the highest PHA (%). C. necator presented the highest PHA yields associating SSF and SmF, however, is not the most suitable microorganism for PHA production by SSF. Concomitant use of C. necator and Bacillus is suggested for future studies in SSF. Also, it discusses the lack of studies on the association of the two fermentation methodologies, and on the scaling of SSF process for PHA production. In addition to demonstrating the need for standardization of results, for comparison between different methodologies.


Assuntos
Bacillus , Cupriavidus necator , Fermentação , Biomassa , Carbono
8.
Eur Radiol ; 32(8): 5596-5605, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35294587

RESUMO

OBJECTIVES: Higher static magnetic field (SMF) enables higher imaging capability in magnetic resonance imaging (MRI), which encourages the development of ultra-high field MRIs above 20 T with a prerequisite for safety issues. However, animal tests of ≥ 20 T SMF exposure are very limited. The objective of the current study is to evaluate mice behaviour consequences of 3.5-23.0 T SMF exposure. METHODS: We systematically examined 112 mice for their short- and long-term behaviour responses to a 2-h exposure of 3.5-23.0 T SMFs. Locomotor activity and cognitive functions were measured by five behaviour tests, including balance beam, open field, elevated plus maze, three-chamber social recognition, and Morris water maze tests. RESULTS: Besides the transient short-term impairment of the sense of balance and locomotor activity, the 3.5-23.0 T SMFs did not have long-term negative effects on mice locomotion, anxiety level, social behaviour, or memory. In contrast, we observed anxiolytic effects and positive effects on social and spatial memory of SMFs, which is likely correlated with the significantly increased CaMKII level in the hippocampus region of high SMF-treated mice. CONCLUSIONS: Our study showed that the short exposures to high-field SMFs up to 23.0 T have negligible side effects on healthy mice and may even have beneficial outcomes in mice mood and memory, which is pertinent to the future medical application of ultra-high field SMFs in MRIs and beyond. KEY POINTS: • Short-term exposure to magnetic fields up to 23.0 T is safe for mice. • High-field static magnetic field exposure transiently reduced mice locomotion. • High-field static magnetic field enhances memory while reduces the anxiety level.


Assuntos
Campos Magnéticos , Imageamento por Ressonância Magnética , Animais , Cognição , Imageamento por Ressonância Magnética/efeitos adversos , Camundongos
9.
Bioelectromagnetics ; 43(4): 278-291, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35485707

RESUMO

With the wide application of magnetic resonance imaging in hospitals and permanent magnets in household items, people have increased exposure to various types of static magnetic fields (SMFs) with moderate and high intensities, which has caused a considerable amount of public concern. Studies have shown that some aspects of gametogenesis and early embryonic development can be significantly affected by SMFs, while others have shown no effects. This review summarizes the experimental results of moderate to high-intensity SMFs (1 mT-16.7 T) on the reproductive development of different model animals, and we find that the effects of SMFs are variable depending on experimental conditions. In general, the effects of inhomogeneous SMFs seem to be more significant compared to that of homogeneous SMFs, which is likely due to magnetic forces generated by the magnetic field gradient. Moreover, some electromagnetic fields may have induced bioeffects because of nonnegligible gradient and heat effect, which are much reduced in superconducting magnets. We hope this review can provide a starting point for more in-depth analysis of various SMFs on reproduction, which is indispensable for evaluating the safety and potential applications of SMFs on living organisms in the future. © 2022 Bioelectromagnetics Society.


Assuntos
Campos Eletromagnéticos , Campos Magnéticos , Animais , Humanos , Imageamento por Ressonância Magnética , Imãs , Reprodução
10.
Ecotoxicol Environ Saf ; 240: 113671, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35653972

RESUMO

With the wide application of static magnetic fields (SMFs), the risk of living organisms exposed to man-made magnetic fields that the intensity is much higher than geomagnetic field has gradually increased. Reproductive system is highly sensitive to environmental stress; however, the influence of high SMFs on reproduction system is still largely unknown. Here we explored the biological responses of SMFs exposure at an intensity of 10 T on the sperms and their offspring in him-5 male mutants of Caenorhabditis elegans (C. elegans). The size of unactivated sperms was deceased by 10 T SMF exposure, instead of the morphology. Exposure to 10 T SMF significantly altered the function of sperms in him-5 worms including the activation of sperms and the non-transferred ratio of sperms. In addition, the brood size assay revealed that 10 T SMF exposure eventually diminished the reproductive capacity of him-5 male worms. The lifespan of outcrossed offspring from exposed him-5 male mutants and unexposed fog-2 female mutants was decreased by 10 T SMF in a time dependent manner. Together, our findings provide novel information regarding the adverse effects of high SMFs on the sperms of C. elegans and their offspring, which can improve our understanding of the fundamental aspects of high SMFs on biological system.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Feminino , Humanos , Longevidade , Campos Magnéticos , Masculino , Reprodução
11.
Surg Endosc ; 35(7): 3732-3743, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32794046

RESUMO

BACKGROUND: Peroral endoscopic myotomy (POEM) has been shown to be effective for achalasia patients. Our study aimed to analyze the clinical outcomes of POEM for challenging patients. METHODS: We retrospectively enrolled 278 challenging achalasia patients who underwent POEM from January 2011 to July 2019. The outcomes of POEM such as procedure time, adverse events, and risk factors of adverse events were analyzed. RESULTS: Of the 278 patients (134 males and 144 females) with a mean age of 47.0 years, 103, 223, 93, and 98 patients had prior treatment and were Ling classification IIc/III, submucosal fibrosis (SMF) classification 2/3, and esophageal mucosa in achalasia (EMIA) classification c/d/e/f, respectively. The mean procedure time was 45.9 min (range, 15-158 min). The mean length of the tunnel and myotomy were 10.1 cm (range, 7-17 cm) and 6.6 cm (range, 5-13 cm), respectively. The major adverse event rate was 14.1%, while the minor adverse event rate was 4.7%. SMF classification 2/3 was an independent risk factor for incomplete tunneling, adverse events, and procedure time ≥ 90 min. The mean follow-up time was 37.2 months (range 1-99 months). The mean Eckardt score and esophageal sphincter pressure were both significantly declined postoperatively. The clinical success rate was 95.6%. CONCLUSION: POEM is safe and effective for challenging achalasia patients. SMF classification grade 2/3 was shown to be an independent risk factor for incomplete tunneling, adverse events, and procedure time ≥ 90 min. For these patients, POEM should be performed by experienced endoscopists, some cases are better served with traditional surgery, such as minimally invasive Heller with Dor fundoplication.


Assuntos
Acalasia Esofágica , Miotomia , Cirurgia Endoscópica por Orifício Natural , Acalasia Esofágica/cirurgia , Esfíncter Esofágico Inferior/cirurgia , Esofagoscopia , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Estudos Retrospectivos , Resultado do Tratamento
12.
Bioelectromagnetics ; 42(2): 115-127, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33508148

RESUMO

Pain is one of the most common reasons why people seek medical care, which is related to most disease states. Magnetic fields (MFs) can be applied locally to specific parts of human bodies with high penetration and temporal control, which have a long-debated history in folk therapy. The purpose of this review is to collect and analyze experimental data about the analgesic effects of static magnetic fields (SMFs) so that we can have a scientific understanding regarding this topic. We collected 28 studies (25 English and 3 Chinese papers) with proper sham controls that investigated the effects of SMFs on pain relief in humans or mice. We found that 64% of the human studies and all mice studies in the literature showed positive analgesic effects of SMFs, which are related to factors including SMF intensity, treatment time, and pain types. Higher intensity and/or longer treatment time, as well as some specific pain types, may have better pain relief effects. Initial mechanistic studies indicated that membrane receptors, such as capsaicin receptor VR1/TRPV1, opioid receptors, and P2X3 receptors, might be involved. By describing experimental evidence and analysis, we found that SMFs actually hold considerable promise for managing some specific types of pain if proper SMF parameters are used. More studies comprehensively evaluating the parameters of SMF and its corresponding analgesic effects on different pain types, as well as the underlying molecular mechanisms, will be necessary to further validate its therapeutic potential in pain management in the future. Bioelectromagnetics. 00:00-00, 2021. © 2021 Bioelectromagnetics Society.


Assuntos
Analgésicos , Campos Magnéticos , Manejo da Dor/métodos , Animais , Humanos , Camundongos
13.
Ecotoxicol Environ Saf ; 209: 111791, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360211

RESUMO

A recently isolated osmo-tolerant yeast Candida tropicalis A1, which could decolorize various azo dyes under high-salinity conditions, was systematically characterized in the present study. Stimulating dye-decolorization effectiveness and osmo-tolerance of the yeast by static magnetic field (SMF) was investigated and transcriptomic responses of the yeast to SMF was analyzed to propose possible mechanisms. The results demonstrated that the yeast A1 effectively decolorized (≥ 97.50% within 12 h) and detoxified (from high toxicity to low toxicity within 24 h) 70 mg/L Acid Red B (ARB) under the optimized conditions through a series of steps including naphthalene-amidine bond cleavage, reductive or oxidative deamination/desulfurization, open-loop of hydroxy-substituted naphthalene or benzene and TCA cycle. Moreover, dye decolorization performance and osmo-tolerance of the yeast A1 were further improved by 24.6 mT SMF. Genes encoding high-affinity hexose/glucose transporter proteins and NADH-ubiquinone oxidoreductase were up-regulated by 24.6 mT SMF, which might be responsible for the increase of dye decolorization. Significant up-regulation of glycerol-3-phosphate dehydrogenase and cell wall protein RHD3 suggested that osmo-tolerance was enhanced by 24.6 mT SMF through promoting production and intracellular accumulation of glycerol as compatible solute, as well as regulation of cell wall component. In conclusion, 24.6 mT SMF led to the up-regulation of related genes resulting in enhanced dye biodegradation efficiency and osmo-tolerance of the yeast A1.


Assuntos
Compostos Azo/metabolismo , Biodegradação Ambiental , Candida tropicalis/fisiologia , Antagonistas de Receptores de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Compostos Azo/química , Candida tropicalis/metabolismo , Corantes/química , Naftalenossulfonatos , Transcriptoma
14.
Electromagn Biol Med ; 40(1): 11-25, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33073612

RESUMO

Among haematological parameters of patients seriously ill with the coronavirus infectious disease 2019 (COVID-19), leucocytosis, lymphocytopenia, and the abnormal release of circulating cytokines, termed cytokine storm syndrome (CSS, also known as cytokine release syndrome or CRS), were found associated with disease severity. In particular, according to the serum cytokine profiling, pro-inflammatory interleukin 6 (IL-6) and anti-inflammatory interleukin 10 (IL-10) were observed to be considerably higher in patients experiencing respiratory distress, septic shock and/or multi-organ failure, namely "critical cases" requiring intensive care unit (ICU) admission, very often resulting in death. Interestingly, the production of these cytokines from human lymphocytes was found to be modulated by exposure of 24 h to a 554.2-553.8 mT inhomogeneous static magnetic field (SMF), which elicits IL-10 and suppresses IL-6. Thus, herein, with the aim of restoring lymphocyte count and physiological serum levels of IL-6 and IL-10, the infusion of human leukocyte antigen (HLA)-matched and SMF-exposed allogenic lymphocytes is proposed for the first time as an easy and affordable treatment option for COVID-19 patients. Even if the count of lymphocytes in COVID-19 patients is very low, SMF exposure may be a valuable tool for reprogramming autologous lymphocytes towards physiological conditions. Furthermore, the same procedure could be extended to include the whole autologous or allogenic white blood cells (WBCs). Time-varying/pulsed magnetic fields exerting comparable cell effects could also be employed.


Assuntos
COVID-19/complicações , Síndrome da Liberação de Citocina/terapia , Antígenos HLA/imunologia , Linfócitos/citologia , Linfopenia/terapia , Campos Magnéticos , Síndrome da Liberação de Citocina/complicações , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/patologia , Humanos , Imunoterapia , Interleucina-6/química , Interleucina-6/metabolismo , Linfócitos/imunologia , Linfopenia/complicações , Linfopenia/imunologia , Linfopenia/patologia , Modelos Moleculares , Conformação Proteica , Transdução de Sinais/imunologia
15.
Chemistry ; 26(71): 17097-17102, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-32592412

RESUMO

Reasonably designing and synthesizing advanced electrode materials is significant to enhance the electrochemical performance of lithium ion batteries (LIBs). Herein, a metal-organic framework (MOF, Mil-125) was used as a precursor and template to successfully synthesize the porous mooncake-shaped Li4 Ti5 O12 (LTO) anode material assembled from nanoparticles. Even more critical, SmF3 was used to modify the prepared porous mooncake-shaped LTO material. The SmF3 -modified LTO maintained a porous mooncake-shaped structure with a large specific surface area, and the SmF3 nanoparticles were observed to be attach on the surface of the LTO material. It has been proven that the SmF3 modification can further facilitate the transition from Ti4+ to Ti3+ , reduce the polarization of electrode, decrease charge transfer impedance (Rct ) and solid electrolyte interface impedance (Rsei ), and increase the lithium ion diffusion coefficient (DLi ), thereby enhancing the electrochemical performance of LTO. Therefore, the porous mooncake-shaped LTO modified using 2 wt % SmF3 displays a large specific discharge capacity of 143.8 mAh g-1 with an increment of 79.16 % compared to pure LTO at a high rate of 10 C (1 C=170 mAh g-1 ), and shows a high retention rate of 96.4 % after 500 cycles at 5 C-rate.

16.
J Biol Phys ; 46(2): 151-167, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32193688

RESUMO

Continuous exposure of 395 nm light increases the fluorescence emission intensity of photosynthetic purple non-sulphur bacteria, Rhodobacter capsulatus (SB1003). We show that such an increase in fluorescence emission of extracellular pigment complexes (PC) from these photosynthetic bacteria depends on the concentration of the pigment and temperature and can also be modulated by the static magnetic field. The time-dependent enhanced emission disappears either at or below 300 K or below a threshold sample concentration (0.1 mg/ml). The enhanced emission reappears at this condition (T < 278 K) if a static magnetic field (395 mT) is introduced during fluorescence measurement. The time dependence of emission is expressed in terms of a first-order rate constant, k = dF/(Fdt). The sign of k shifts from positive to negative as PC concentration is lowered than a threshold value, implying onset of fluorescence decay (k < 0) rather than amplification (k > 0). At PC concentration higher than a threshold, k becomes negative if the temperature is lowered. But, surprisingly, at low temperature, a static magnetic field reverts the k value to positive. We explain the logical nature of k-switching and photo-dynamics of the aforesaid microbial fluorescence emission by aggregation of protoporphyrin rings present in the PC. While the simultaneous presence of decay in fluorescence and susceptibility to static magnetic field suggests the dominance of triplet states at low temperatures, the process is reversed by SMF-induced removal of spin degeneracy. At higher temperatures, the optical excitability and lack of magnetic response suggest the dominance of singlet states. We propose that the restructuring of the singlet-triplet distribution by intersystem crossing may be the basis of this logical behaviour. In context with microbial function, time-dependent enhancement of fluorescence also implies relay of red photons to the neighbouring microbes not directly exposed to the incident radiation, thus serving as an indirect photosynthetic regulator.


Assuntos
Fluorescência , Campos Magnéticos , Rhodobacter capsulatus/metabolismo , Temperatura , Pigmentação , Fatores de Tempo
17.
Molecules ; 25(6)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204392

RESUMO

One of the most relevant drawbacks in medicine is the ability of drugs and/or imaging agents to reach cells. Nanotechnology opened new horizons in drug delivery, and silver nanoparticles (AgNPs) represent a promising delivery vehicle for their adjustable size and shape, high-density surface ligand attachment, etc. AgNPs cellular uptake involves different endocytosis mechanisms, including lipid raft-mediated endocytosis. Since static magnetic fields (SMFs) exposure induces plasma membrane perturbation, including the rearrangement of lipid rafts, we investigated whether SMF could increase the amount of AgNPs able to pass the peripheral blood lymphocytes (PBLs) plasma membrane. To this purpose, the effect of 6-mT SMF exposure on the redistribution of two main lipid raft components (i.e., disialoganglioside GD3, cholesterol) and on AgNPs uptake efficiency was investigated. Results showed that 6 mT SMF: (i) induces a time-dependent GD3 and cholesterol redistribution in plasma membrane lipid rafts and modulates gene expression of ATP-binding cassette transporter A1 (ABCA1), (ii) increases reactive oxygen species (ROS) production and lipid peroxidation, (iii) does not induce cell death and (iv) induces lipid rafts rearrangement, that, in turn, favors the uptake of AgNPs. Thus, it derives that SMF exposure could be exploited to enhance the internalization of NPs-loaded therapeutic or diagnostic molecules.


Assuntos
Linfócitos/citologia , Microdomínios da Membrana/metabolismo , Prata/farmacocinética , Transportador 1 de Cassete de Ligação de ATP , Adulto , Transporte Biológico , Endocitose , Feminino , Humanos , Peroxidação de Lipídeos , Linfócitos/química , Campos Magnéticos , Masculino , Nanopartículas Metálicas , Espécies Reativas de Oxigênio/metabolismo , Prata/química
18.
Electromagn Biol Med ; 39(4): 298-309, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32666844

RESUMO

Thirteen million cancer deaths and 21.7 million new cancer cases are expected in the world by 2030. Glioblastoma is the most common primary malignant tumor of the central nervous system which is the most lethal type of primary brain tumor in adults with the survival time of 12-15 months after the initial diagnosis. Glioblastoma is the most common and most malignant type of brain tumor, and despite surgery, chemotherapy and radiation treatment, the average survival of patients is about 14 months. The current research showed that the frequency magnetic field (FMF) and static magnetic field (SMF) can influence cancer cell proliferation and coupled with anticancer drugs may provide a new strategy for cancer therapy. At the present study, we investigated the effects of FMF (10 Hz, 50 G), SMF (50 G) and Temozolomide (200 µm) on viability, free radical production, and p53 followed by p53 protein expression in the human glioblastoma cell line (A172) by MTT, NBT, RT-PCR and Western blot. Results showed that the effect of Temozolomide (TMZ) with SMF and FMF together increased the cytotoxicity, free radical production, and p53 followed by p53 protein expression in the human glioblastoma cell line (A172).


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Radicais Livres/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Campos Magnéticos , Temozolomida/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Proteína Supressora de Tumor p53/genética
19.
Neuroimage ; 199: 273-280, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158482

RESUMO

People are exposed to various magnetic fields, including the high static/steady magnetic field (SMF) of MRI, which has been increased to 9.4 T in preclinical investigations. However, relevant safety studies about high SMF are deficient. Here we examined whether 3.5-23.0 T SMF exposure for 2 h has severe long-term effects on mice using 112 C57BL/6J mice. The food/water consumption, blood glucose levels, blood routine, blood biochemistry, as well as organ weight and HE stains were all examined. The food consumption and body weight were slightly decreased for 23.0 T-exposed mice (14.6%, P < 0.01, and 1.75-5.57%, P < 0.05, respectively), but not the other groups. While total bilirubin (TBIL), white blood cells, platelet and lymphocyte numbers were affected by some magnetic conditions, most of them were still within normal reference range. Although 13.5 T magnetic fields with the highest gradient (117.2 T/m) caused spleen weight increase, the blood count and biochemistry results were still within the control reference range. Moreover, the highest field 23.0 T with no gradient did not cause organ weight or blood biochemistry abnormality, which indicates that field gradient is a key parameter. Collectively, these data suggest 3.5-23.0 T static magnetic field exposure for 2 h do not have severe long-term effects on mice.


Assuntos
Campos Magnéticos/efeitos adversos , Imageamento por Ressonância Magnética/efeitos adversos , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
RNA ; 23(7): 1068-1079, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28373290

RESUMO

To identify regulators of pre-mRNA splicing in plants, we developed a forward genetic screen based on an alternatively spliced GFP reporter gene in Arabidopsis thaliana In wild-type plants, three major splice variants issue from the GFP gene but only one represents a translatable GFP mRNA. Compared to wild-type seedlings, which exhibit an intermediate level of GFP expression, mutants identified in the screen feature either a "GFP-weak" or "Hyper-GFP" phenotype depending on the ratio of the three splice variants. GFP-weak mutants, including previously identified prp8 and rtf2, contain a higher proportion of unspliced transcript or canonically spliced transcript, neither of which is translatable into GFP protein. In contrast, the coilin-deficient hyper-gfp1 (hgf1) mutant displays a higher proportion of translatable GFP mRNA, which arises from enhanced splicing of a U2-type intron with noncanonical AT-AC splice sites. Here we report three new hgf mutants that are defective, respectively, in spliceosome-associated proteins SMU1, SmF, and CWC16, an Yju2/CCDC130-related protein that has not yet been described in plants. The smu1 and cwc16 mutants have substantially increased levels of translatable GFP transcript owing to preferential splicing of the U2-type AT-AC intron, suggesting that SMU1 and CWC16 influence splice site selection in GFP pre-mRNA. Genome-wide analyses of splicing in smu1 and cwc16 mutants revealed a number of introns that were variably spliced from endogenous pre-mRNAs. These results indicate that SMU1 and CWC16, which are predicted to act directly prior to and during the first catalytic step of splicing, respectively, function more generally to modulate splicing patterns in plants.


Assuntos
Arabidopsis/genética , Proteínas Nucleares/metabolismo , RNA de Plantas/genética , Processamento Alternativo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Genes Reporter , Mutação , Proteínas Nucleares/genética
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