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1.
BMC Plant Biol ; 24(1): 383, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724888

RESUMO

Taxus chinensis (Taxus cuspidata Sieb. et Zucc.) is a traditional medicinal plant known for its anticancer substance paclitaxel, and its growth age is also an important factor affecting its medicinal value. However, how age affects the physiological and metabolic characteristics and active substances of T. chinensis is still unclear. In this study, carbon and nitrogen accumulation, contents of active substances and changes in primary metabolites in barks and annual leaves of T. chinensis of different diameter classes were investigated by using diameter classes instead of age. The results showed that leaves and barks of small diameter class (D1) had higher content of non-structural carbohydrates and C, which were effective in enhancing defense capacity, while N content was higher in medium (D2) and large diameter classes (D3). Active substances such as paclitaxel, baccatin III and cephalomannine also accumulated significantly in barks of large diameter classes. Moreover, 21 and 25 differential metabolites were identified in leaves and barks of different diameter classes, respectively. The differential metabolites were enhanced the TCA cycle and amino acid biosynthesis, accumulate metabolites such as organic acids, and promote the synthesis and accumulation of active substances such as paclitaxel in the medium and large diameter classes. These results revealed the carbon and nitrogen allocation mechanism of different diameter classes of T. chinensis, and its relationship with medicinal components, providing a guidance for the harvesting and utilization of wild T. chinensis.


Assuntos
Carbono , Metabolômica , Nitrogênio , Folhas de Planta , Taxus , Taxus/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Folhas de Planta/metabolismo , Casca de Planta/metabolismo , Casca de Planta/química
2.
Anal Chim Acta ; 1307: 342627, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719406

RESUMO

BACKGROUND: Hydrogen peroxide (H2O2) is an important reactive oxygen species (ROS) molecule involved in cell metabolism regulation, transcriptional regulation, and cytoskeleton remodeling. Real-time monitoring of H2O2 levels in live cells is of great significance for disease prevention and diagnosis. RESULTS: We utilized carbon cloth (CC) as the substrate material and employed a single-atom catalysis strategy to prepare a flexible self-supported sensing platform for the real-time detection of H2O2 secreted by live cells. By adjusting the coordination structure of single-atom sites through P and S doping, a cobalt single-atom nanoenzyme Co-NC/PS with excellent peroxidase-like activity was obtained. Furthermore, we explored the enzyme kinetics and possible catalytic mechanism of Co-NC/PS. Due to the excellent flexibility, high conductivity, strong adsorption performance of carbon cloth, and the introduction of non-metallic atom-doped active sites, the developed Co-NC/PS@CC exhibited ideal sensing performance. Experimental results showed that the linear response range for H2O2 was 1-17328 µM, with a detection limit (LOD) of 0.1687 µM. Additionally, the sensor demonstrated good reproducibility, repeatability, anti-interference, and stability. SIGNIFICANCE: The Co-NC/PS@CC prepared in this study has been successfully applied for detecting H2O2 secreted by MCF-7 live cells, expanding the application of single-atom nanoenzymes in live cell biosensing, with significant implications for health monitoring and clinical diagnostics.


Assuntos
Cobalto , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Cobalto/química , Humanos , Técnicas Eletroquímicas/métodos , Células MCF-7 , Carbono/química , Limite de Detecção , Técnicas Biossensoriais/métodos
3.
Int J Mol Sci ; 25(9)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38732193

RESUMO

One-carbon (1-C) metabolic deficiency impairs homeostasis, driving disease development, including infertility. It is of importance to summarize the current evidence regarding the clinical utility of 1-C metabolism-related biomolecules and methyl donors, namely, folate, betaine, choline, vitamin B12, homocysteine (Hcy), and zinc, as potential biomarkers, dietary supplements, and culture media supplements in the context of medically assisted reproduction (MAR). A narrative review of the literature was conducted in the PubMed/Medline database. Diet, ageing, and the endocrine milieu of individuals affect both 1-C metabolism and fertility status. In vitro fertilization (IVF) techniques, and culture conditions in particular, have a direct impact on 1-C metabolic activity in gametes and embryos. Critical analysis indicated that zinc supplementation in cryopreservation media may be a promising approach to reducing oxidative damage, while female serum homocysteine levels may be employed as a possible biomarker for predicting IVF outcomes. Nonetheless, the level of evidence is low, and future studies are needed to verify these data. One-carbon metabolism-related processes, including redox defense and epigenetic regulation, may be compromised in IVF-derived embryos. The study of 1-C metabolism may lead the way towards improving MAR efficiency and safety and ensuring the lifelong health of MAR infants.


Assuntos
Carbono , Técnicas de Reprodução Assistida , Humanos , Carbono/metabolismo , Vitamina B 12/metabolismo , Fertilização in vitro/métodos , Feminino , Homocisteína/metabolismo , Homocisteína/sangue , Ácido Fólico/metabolismo , Suplementos Nutricionais , Colina/metabolismo , Zinco/metabolismo , Betaína/metabolismo , Biomarcadores
4.
Anal Chem ; 96(19): 7516-7523, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691765

RESUMO

Herein, single-atom iron doped carbon dots (SA Fe-CDs) were successfully prepared as novel electrochemiluminescence (ECL) emitters with high ECL efficiency, and a biosensor was constructed to ultrasensitively detect microRNA-222 (miRNA-222). Importantly, compared with the conventional without single-atom doped CDs with low ECL efficiency, SA Fe-CDs exhibited strong ECL efficiency, in which single-atom iron as an advanced coreactant accelerator could significantly enhance the generation of reactive oxygen species (ROS) from the coreactant S2O82- for improving the ECL efficiency. Moreover, a neoteric amplification strategy combining the improved strand displacement amplification with Nt.BbvCI enzyme-induced target amplification (ISDA-EITA) could produce 4 output DNAs in every cycle, which greatly improved the amplification efficiency. Thus, a useful ECL biosensor was built with a detection limit of 16.60 aM in the range of 100 aM to 1 nM for detecting traces of miRNA-222. In addition, miRNA-222 in cancer cell lysate (MHCC-97L) was successfully detected by using the ECL biosensor. Therefore, this strategy provides highly efficient single-atom doped ECL emitters for the construction of sensitive ECL biosensing platforms in the biological field and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Carbono , Técnicas Eletroquímicas , Ferro , Medições Luminescentes , MicroRNAs , Pontos Quânticos , MicroRNAs/análise , Carbono/química , Ferro/química , Técnicas Eletroquímicas/métodos , Pontos Quânticos/química , Humanos , Técnicas Biossensoriais/métodos , Limite de Detecção
5.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731398

RESUMO

(1) Background: Alzheimer's disease (AD) is characterized by ß-amyloid (Aß) peptide accumulation and mitochondrial dysfunction during the early stage of disease. PINK1 regulates the balance between mitochondrial homeostasis and bioenergy supply and demand via the PINK1/Parkin pathway, Na+/Ca2+ exchange, and other pathways. (2) Methods: In this study, we synthesized positively charged carbon dots (CA-PEI CDs) using citric acid (CA) and polyethyleneimine (PEI) and used them as vectors to express PINK1 genes in the APP/PS1-N2a cell line to determine mitochondrial function, electron transport chain (ETC) activity, and ATP-related metabolomics. (3) Results: Our findings showed that the CA-PEI CDs exhibit the characteristics of photoluminescence, low toxicity, and concentrated DNA. They are ideal biological carriers for gene delivery. PINK1 overexpression significantly increased the mitochondrial membrane potential in APP/PS1-N2a cells and reduced reactive-oxygen-species generation and Aß1-40 and Aß1-42 levels. An increase in the activity of NADH ubiquinone oxidoreductase (complex I, CI) and cytochrome C oxidase (complex IV, CIV) induces the oxidative phosphorylation of mitochondria, increasing ATP generation. (4) Conclusions: These findings indicate that the PINK gene can alleviate AD by increasing bioenergetic metabolism, reducing Aß1-40 and Aß1-42, and increasing ATP production.


Assuntos
Trifosfato de Adenosina , Carbono , Ácido Cítrico , Mitocôndrias , Polietilenoimina , Proteínas Quinases , Polietilenoimina/química , Carbono/química , Trifosfato de Adenosina/metabolismo , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Pontos Quânticos/química , Animais , Peptídeos beta-Amiloides/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Humanos , Linhagem Celular , Espécies Reativas de Oxigênio/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo
6.
Molecules ; 29(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731499

RESUMO

Carbon nanodots (CDs) are commonly found in food products and have attracted significant attention from food scientists. There is a high probability of CD exposure in humans, but its impacts on health are unclear. Therefore, health effects associated with CD consumption should be investigated. In this study, we attempted to create a model system of the Maillard reaction between cystine and glucose using a simple cooking approach. The CDs (CG-CDs) were isolated from cystine-glucose-based Maillard reaction products and characterized using fluorescence spectroscopy, X-ray diffractometer (XRD), and transmission electron microscope (TEM). Furthermore, human mesenchymal stem cells (hMCs) were used as a model to unravel the CDs' cytotoxic properties. The physiochemical assessment revealed that CG-CDs emit excitation-dependent fluorescence and possess a circular shape with sizes ranging from 2 to 13 nm. CG-CDs are predominantly composed of carbon, oxygen, and sulfur. The results of the cytotoxicity evaluation indicate good biocompatibility, where no severe toxicity was observed in hMCs up to 400 µg/mL. The DPPH assay demonstrated that CDs exert potent antioxidant abilities. The qPCR analysis revealed that CDs promote the downregulation of the key regulatory genes, PPARγ, C/EBPα, SREBP-1, and HMGCR, coupled with the upregulation of anti-inflammatory genes. Our findings suggested that, along with their excellent biocompatibility, CG-CDs may offer positive health outcomes by modulating critical genes involved in lipogenesis, homeostasis, and obesity pathogenesis.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Carbono , Reação de Maillard , Células-Tronco Mesenquimais , PPAR gama , Proteína de Ligação a Elemento Regulador de Esterol 1 , Humanos , Carbono/química , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Pontos Quânticos/química , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Enxofre/química
7.
J Colloid Interface Sci ; 668: 618-633, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38696990

RESUMO

Tumor metastasis and recurrence are closely related to immune escape and hypoxia. Chemodynamic therapy (CDT), photodynamic therapy (PDT), and photothermal therapy (PTT) can induce immunogenic cell death (ICD), and their combination with immune checkpoint agents is a promising therapeutic strategy. Iron based nanomaterials have received more and more attention, but their low Fenton reaction efficiency has hindered their clinical application. In this study, Fe3O4-carbon dots complex (Fe3O4-CDs) was synthesized, which was modified with ferrocenedicarboxylic acid by amide bond, and crosslinked into Fe3O4-CDs@Fc nano complex. The CDs catalyzed the Fenton reaction activity of Fe3O4 by helping to improve the electron transfer efficiency, extended the reaction pH condition to 7.4. The Fe3O4-CDs@Fc exhibit exceptional optical activity, achieving a thermal conversion efficiency of 56.43 % under 808 nm light and a photosensitive single-line state oxygen quantum yield of 33 % under 660 nm light. Fe3O4-CDs@Fc improved intracellular oxygen level and inhibited hypoxia-inducing factor (HIF-1α) by in-situ oxygen production based on Fenton reaction. The multimodal combination of Fe3O4-CDs@Fc (CDT/PDT/PTT) strongly induced immune cell death (ICD). The expression of immune-related protein and HIF-1α was investigated by immunofluorescence method. In vivo, Fe3O4-CDs@Fc combined with immune checkpoint blocker (antibody PD-L1, αPD-L1) effectively ablated primary tumors and inhibited distal tumor growth. Fe3O4-CDs@Fc is a promising immune-antitumor drug.


Assuntos
Carbono , Oxigênio , Pontos Quânticos , Camundongos , Animais , Pontos Quânticos/química , Carbono/química , Humanos , Catálise , Oxigênio/química , Imunoterapia , Tamanho da Partícula , Antineoplásicos/farmacologia , Antineoplásicos/química , Fotoquimioterapia , Camundongos Endogâmicos BALB C , Linhagem Celular Tumoral , Ferro/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Propriedades de Superfície , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino
8.
J Colloid Interface Sci ; 668: 132-141, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38669991

RESUMO

A key challenge to enhance the therapeutic outcome of photothermal therapy (PTT) is to improve the efficiency of passive targeted accumulation of photothermal agents at tumor sites. Carbon dots (CDs) are an ideal choice for application as photothermal agents because of their advantages such as adjustable fluorescence, high photothermal conversion efficiency, and excellent biocompatibility. Here, we synthesized polylysine-modified near-infrared (NIR)-emitting CDs assemblies (plys-CDs) through post-solvothermal reaction of NIR-emitting CDs with polylysine. The encapsulated structure of plys-CDs was confirmed by determining morphological, chemical, and luminescent properties. The particle size of CDs increased to approximately 40 ± 8 nm after polylysine modification and was within the size range appropriate for achieving superior enhanced permeability and retention effect. Plys-CDs maintained a high photothermal conversion efficiency of 54.9 %, coupled with increased tumor site accumulation, leading to a high efficacy in tumor PTT. Thus, plys-CDs have a great potential for application in photothermal ablation therapy of tumors.


Assuntos
Carbono , Raios Infravermelhos , Tamanho da Partícula , Terapia Fototérmica , Polilisina , Pontos Quânticos , Polilisina/química , Carbono/química , Animais , Pontos Quânticos/química , Camundongos , Humanos , Camundongos Endogâmicos BALB C , Propriedades de Superfície , Feminino , Sobrevivência Celular/efeitos dos fármacos , Neoplasias/terapia , Neoplasias/patologia
9.
Bioresour Technol ; 401: 130733, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670287

RESUMO

This study investigated the mediating effect of Triethanolamine on Fe@C-Rhodobacter sphaeroides hybrid photosynthetic system to achieve efficient biohydrogen production. The biocompatible Fe@C generates excited electrons upon exposure to light, releasing ferrum for nitrogenase synthesis, and regulating the pH of the fermentation environment. Triethanolamine was introduced to optimize the electron transfer chain, thereby improving system stability, prolonging electron lifespan, and facilitating ferrum corrosion. This, in turn, stimulated the lactic acid synthetic metabolic pathway of Rhodobacter sphaeroides, resulting in increased reducing power in the biohybrid system. The ternary coupling system was analyzed through the regulation of concentration, initial pH, and light intensity. The system achieved the highest total H2 production of 5410.9 mL/L, 1.29 times higher than the control (2360.5 mL/L). This research provides a valuable strategy for constructing ferrum-carbon-based composite-cellular biohybrid systems for photo-fermentation H2 production.


Assuntos
Etanolaminas , Hidrogênio , Luz , Rhodobacter sphaeroides , Rhodobacter sphaeroides/metabolismo , Hidrogênio/metabolismo , Etanolaminas/metabolismo , Etanolaminas/química , Ferro/química , Catálise , Concentração de Íons de Hidrogênio , Carbono , Fermentação , Fotossíntese
10.
J Colloid Interface Sci ; 668: 293-302, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38678885

RESUMO

Understanding the cytotoxicity of fluorescent carbon dots (CDs) is crucial for their applications, and various biochemical assays have been used to study the effects of CDs on cells. Knowledge on the effects of CDs from a biophysical perspective is integral to the recognition of their cytotoxicity, however the related information is very limited. Here, we report that atomic force microscopy (AFM) can be used as an effective tool for studying the effects of CDs on cells from the biophysical perspective. We achieve this by integrating AFM-based nanomechanics with AFM-based imaging. We demonstrate the performance of this method by measuring the influence of CDs on living human neuroblastoma (SH-SY5Y) cells at the single-cell level. We find that high-dose CDs can mechanically induce elevated normalized hysteresis (energy dissipation during the cell deformation) and structurally impair actin skeleton. The nanomechanical change highly correlates with the alteration of actin filaments, indicating that CDs-induced changes in SH-SY5Y cells are revealed in-depth from the AFM-based biophysical aspect. We validate the reliability of the biophysical observations using conventional biological methods including cell viability test, fluorescent microscopy, and western blot assay. Our work contributes new and significant information on the cytotoxicity of CDs from the biophysical perspective.


Assuntos
Carbono , Sobrevivência Celular , Microscopia de Força Atômica , Pontos Quânticos , Humanos , Carbono/química , Pontos Quânticos/química , Sobrevivência Celular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Linhagem Celular Tumoral , Tamanho da Partícula , Propriedades de Superfície , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/efeitos dos fármacos , Actinas/metabolismo , Actinas/química
11.
ACS Nano ; 18(18): 11560-11572, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38682810

RESUMO

Second near-infrared (NIR-II) carbon dots, with absorption or emission between 1000 and 1700 nm, are gaining increasing attention in the biomaterial field due to their distinctive properties, which include straightforward preparation processes, stable photophysical characteristics, excellent biocompatibility, and low cost. As a result, there is a growing focus on the controlled synthesis and modulation of the photochemical and photophysical properties of NIR-II carbon dots, with the aim to further expand their biomedical applications, a current research hotspot. This account aims to provide a comprehensive overview of the recent advancements in NIR-II carbon dots within the biomedical field. The review will cover the following topics: (i) the design, synthesis, and purification of NIR-II carbon dots, (ii) the surface modification strategies, and (iii) the biomedical applications, particularly in the domain of cancer theranostics. Additionally, this account addresses the challenges encountered by NIR-II carbon dots and will outline future directions in the realm of cancer theranostics. By exploring carbon-based NIR-II biomaterials, we can anticipate that this contribution will garner increased attention and contribute to the development of next-generation advanced functional carbon dots, thereby offering enhanced tools and strategies in the biomedical field.


Assuntos
Carbono , Raios Infravermelhos , Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Humanos , Neoplasias/tratamento farmacológico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Animais , Nanomedicina Teranóstica
12.
Proc Natl Acad Sci U S A ; 121(19): e2319022121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38683986

RESUMO

Growth is a function of the net accrual of resources by an organism. Energy and elemental contents of organisms are dynamically linked through their uptake and allocation to biomass production, yet we lack a full understanding of how these dynamics regulate growth rate. Here, we develop a multivariate imbalance framework, the growth efficiency hypothesis, linking organismal resource contents to growth and metabolic use efficiencies, and demonstrate its effectiveness in predicting consumer growth rates under elemental and food quantity limitation. The relative proportions of carbon (%C), nitrogen (%N), phosphorus (%P), and adenosine triphosphate (%ATP) in consumers differed markedly across resource limitation treatments. Differences in their resource composition were linked to systematic changes in stoichiometric use efficiencies, which served to maintain relatively consistent relationships between elemental and ATP content in consumer tissues and optimize biomass production. Overall, these adjustments were quantitatively linked to growth, enabling highly accurate predictions of consumer growth rates.


Assuntos
Biomassa , Carbono , Nitrogênio , Fósforo , Fósforo/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Trifosfato de Adenosina/metabolismo , Modelos Biológicos , Animais
13.
J Photochem Photobiol B ; 255: 112920, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38669742

RESUMO

As a sort of fluorescent carbon nanomaterial with a particle size of less than 10 nm, carbon dots (CDs) have their own merits of good dispersibility in water, stable optical properties, strong chemical inertness, stable optical properties, and good biosecurity. These excellent peculiarities facilitated them like sensing, imaging, medicine, catalysis, and optoelectronics, making them a new star in the field of nanotechnology. In particular, the development of CDs in the fields of chemical probes, imaging, cancer therapy, antibacterial and drug delivery has become a hot topic in current research. Although the biomedical applications in CDs have been demonstrated in many research articles, a systematic summary of their role in biomedical applications is scarce. In this review, we introduced the basic information of CDs in detail, including synthesis approaches of CDs as well as their favorable properties including photoluminescence and low cytotoxicity. Subsequently, the application of CDs in the field of biomedicine was emphasized. Finally, the main challenges and research prospects of CDs in this field were proposed, which might provide some detailed information in designing new CDs in this promising biomedical field.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Humanos , Animais
14.
Chemosphere ; 357: 141910, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582170

RESUMO

Growing quantities of biomass ashes (phyto-ashs) are currently produced worldwide due to the increasing biomass consumption in energy applications. Utilization of phyto-ash in agriculture is environmentally friendly solution. However, mechanisms involving the coordination of carbon metabolism and distribution in plants and soil amendment are not well known. In the present study, tobacco plants were chemically-fertilized with or without 2‰ phyto-ash addition. The control had sole chemical fertilizer; for two phyto-ash treatments, the one (T1) received comparable levels of nitrogen, phophorus, and potassium from phyto-ash and fertilizers as the control and another (T2) had 2‰ of phyto-ash and the same rates of fertilizers as the control. Compared with the control, phyto-ash addition improved the soil pH from 5.94 to about 6.35; T2 treatment enhanced soil available potassium by 30% but no difference of other elements was recorded among three treatments. Importantly, bacterial (but not fungal) communities were significantly enriched by phyto-ash addition, with the rank of richness as: T2 > T1 > control. Consistent with amelioration of soil properties, phyto-ash promoted plant growth through enlarged leaf area and photosynthesis and induced outgrowth of lateral roots (LRs). Interestingly, increased auxin content was recorded in 2nd and 3rd leaves and roots under phyto-ash application, also with the rank level as T2 > T1 > control, paralleling with higher transcripts of auxin synthetic genes in the topmost leaf and stronger [3H]IAA activity under phyto-ash addition. Furthermore, exogenous application of analog exogenous auxin (NAA) restored leaf area, photosynthesis and LR outgrowth to the similar level as T2 treatment; conversely, application of auxin transport inhibitor (NPA) under T2 treatment retarded leaf and root development. We demonstrated that phyto-ash addition improved soil properties and thus facilitated carbon balance within plants and biomass accumulation in which shifting auxin distribution plays an important role.


Assuntos
Biomassa , Fertilizantes , Ácidos Indolacéticos , Solo , Solo/química , Ácidos Indolacéticos/metabolismo , Nicotiana/metabolismo , Nicotiana/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Agricultura/métodos , Nitrogênio/metabolismo , Microbiologia do Solo , Carbono/metabolismo , Potássio/metabolismo
15.
Environ Sci Technol ; 58(18): 7802-7813, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38578665

RESUMO

Carbon neutral or negative mining can potentially be achieved by integrating carbon mineralization processes into the mine design, operations, and closure plans. Brucite [Mg(OH)2] is a highly reactive mineral present in some ultramafic mine tailings with the potential to be rapidly carbonated and can contain significant amounts of ferrous iron [Fe(II)] substituted for Mg; however, the influence of this substitution on carbon mineralization reaction products and efficiency has not been thoroughly constrained. To better assess the efficiency of carbon storage in brucite-bearing tailings, we performed carbonation experiments using synthetic Fe(II)-substituted brucite (0, 6, 23, and 44 mol % Fe) slurries in oxic and anoxic conditions with 10% CO2. Additionally, the carbonation process was evaluated using different background electrolytes (NaCl, Na2SO4, and Na4SiO4). Our results indicate that carbonation efficiency decreases with increasing Fe(II) substitution. In oxic conditions, precipitation of ferrihydrite [Fe10IIIO14(OH)2] and layered double hydroxides {e.g., pyroaurite [Mg6Fe2III(OH)16CO3·4H2O]} limited carbonation efficiency. Carbonation in anoxic environments led to the formation of Fe(II)-substituted nesquehonite (MgCO3·3H2O) and dypingite [Mg5(CO3)4(OH)2·âˆ¼5H2O], as well as chukanovite [Fe2IICO3(OH)2] in the case of 23 and 44 mol % Fe(II)-brucite carbonation. Carbonation efficiencies were consistent between chloride- and sulfate-rich solutions but declined in the presence of dissolved Si due to the formation of amorphous SiO2·nH2O and Fe-Mg silicates. Overall, our results indicate that carbonation efficiency and the long-term fate of stored CO2 may depend on the amount of substituted Fe(II) in both feedstock minerals and carbonate products.


Assuntos
Ferro , Ferro/química , Hidróxido de Magnésio/química , Carbono/química , Mineração , Soluções
16.
Int J Biol Macromol ; 267(Pt 1): 131445, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588839

RESUMO

Carbonized bacterial cellulose embedded with highly dispersed nano zero-valent iron (nZVI), denoted as nZVI@CBC, was prepared through one-step in situ carbothermal treatment of bacterial cellulose adsorbing iron(III) nitrate. The structure characteristics of nZVI@CBC and its performance in removing hexavalent chromium Cr(VI) were investigated. Results showed the formation of nZVI@CBC with a surface area of 409.61 m2/g at 800 °C, with nZVI particles of mean size 28.2 nm well distributed within the fibrous network of CBC. The stability of nZVI was enhanced by its carbon coating, despite some inevitable oxidation of exposed nZVI. Batch experiments demonstrated that nZVI@CBC exhibited superior removal efficiency compared to bare nZVI and CBC. Under optimal conditions, nZVI@CBC exhibited a high Cr(VI) adsorption capacity of up to 372.42 mg/g. Therefore, nZVI@CBC shows promise as an effective adsorbent for remediating Cr(VI) pollution in water.


Assuntos
Celulose , Cromo , Ferro , Poluentes Químicos da Água , Purificação da Água , Cromo/química , Cromo/isolamento & purificação , Celulose/química , Adsorção , Ferro/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Carbono/química , Bactérias
17.
Sci Total Environ ; 927: 172179, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582103

RESUMO

While over-fertilization and nitrogen deposition can lead to the enrichment of nitrogen in soil, its effects on heavy metal fractions under gradient moisture conditions remains unclear. Here, the effect of intensive ammonium (NH4+) addition on the conversion and interaction of cadmium (Cd), iron (Fe) and carbon (C) was studied. At relatively low (30-80 %) water hold capacity (WHC) NH4+ application increased the carbonate bound Cd fraction (F2Cd), while at relatively high (80-100 %) WHC NH4+ application increased the organic matter bound Cd fraction (F4Cd). Iron­manganese oxide bound Cd fractions (F3Cd) and oxalate-Fe decreased, but DCB-Fe increased in NH4+ treatments, indicating that amorphous Fe was the main carrier of F3Cd. The variations in F1Cd and F4Cd observed under the 100-30-100 % WHC treatment were similar to those observed under low moisture conditions (30-60 % WHC). The C=O/C-H ratio of organic matter in soil decreased under the 30-60 % WHC treatment, but increased under the 80-100 % WHC treatment, which was the dominant factor influencing F4Cd changes. The conversion of NH4+ declined with increasing soil moisture content, and the impact on oxalate-Fe was greater at 30-60 % WHC than at 80-100 % WHC. Correspondingly, genetic analysis showed the effect of NH4+ on Fe and C metabolism at 30-60 % WHC was greater than at 80-100 % WHC. Specifically, NH4+ treatment enhanced the expression of genes encoding extracellular Fe complexation (siderophore) at 30-80 % WHC, while inhibiting genes encoding Fe transmembrane transport at 30-60 % WHC, indicating that siderophores simultaneously facilitated Cd detoxification and Fe complexation. Furthermore, biosynthesis of sesquiterpenoid, steroid, butirosin and neomycin was significantly correlated with F4Cd, while glycosaminoglycan degradation metabolism and assimilatory nitrate reduction was significantly correlated with F2Cd. Overall, this study gives a more comprehensive insight into the effect of NH4+ on activated Fe and C conversion on soil Cd redistribution under gradient moisture conditions.


Assuntos
Compostos de Amônio , Cádmio , Carbono , Fertilizantes , Ferro , Oxirredução , Poluentes do Solo , Solo , Cádmio/análise , Solo/química , Poluentes do Solo/análise , Agricultura/métodos , Oryza/metabolismo
18.
Int J Mol Sci ; 25(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38674080

RESUMO

Cellular hypoxia, detectable in up to 80% of non-small cell lung carcinoma (NSCLC) tumors, is a known cause of radioresistance. High linear energy transfer (LET) particle radiation might be effective in the treatment of hypoxic solid tumors, including NSCLC. Cellular hypoxia can activate nuclear factor κB (NF-κB), which can modulate radioresistance by influencing cancer cell survival. The effect of high-LET radiation on NF-κB activation in hypoxic NSCLC cells is unclear. Therefore, we compared the effect of low (X-rays)- and high (12C)-LET radiation on NF-κB responsive genes' upregulation, as well as its target cytokines' synthesis in normoxic and hypoxic A549 NSCLC cells. The cells were incubated under normoxia (20% O2) or hypoxia (1% O2) for 48 h, followed by irradiation with 8 Gy X-rays or 12C ions, maintaining the oxygen conditions until fixation or lysis. Regulation of NF-κB responsive genes was evaluated by mRNA sequencing. Secretion of NF-κB target cytokines, IL-6 and IL-8, was quantified by ELISA. A greater fold change increase in expression of NF-κB target genes in A549 cells following exposure to 12C ions compared to X-rays was observed, regardless of oxygenation status. These genes regulate cell migration, cell cycle, and cell survival. A greater number of NF-κB target genes was activated under hypoxia, regardless of irradiation status. These genes regulate cell migration, survival, proliferation, and inflammation. X-ray exposure under hypoxia additionally upregulated NF-κB target genes modulating immunosurveillance and epithelial-mesenchymal transition (EMT). Increased IL-6 and IL-8 secretion under hypoxia confirmed NF-κB-mediated expression of pro-inflammatory genes. Therefore, radiotherapy, particularly with X-rays, may increase tumor invasiveness in surviving hypoxic A549 cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , NF-kappa B , Humanos , NF-kappa B/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Raios X , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Transferência Linear de Energia , Hipóxia Celular/efeitos da radiação , Carbono , Sobrevivência Celular/efeitos da radiação , Tolerância a Radiação , Interleucina-8/metabolismo , Interleucina-8/genética
19.
Nanoscale ; 16(18): 8843-8850, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38644775

RESUMO

Extensive modifications have been made to the synthesis protocol for porous silica particles to improve the shape, size and yield percentage, but problems associated with improvement in biodegradability and decrease in chances to induce side effects still remain a concern. To circumvent these limitations, a facile modification strategy has been employed through in situ carbonization of porous silica particles. Herein, carbon particles were integrated within porous silica core-shell particles (Si-P-CNPs) during the synthesis process and found to preserve the ordered structural morphology. Curcumin was used as a model drug for loading in prepared Si-P-CNPs whereas lung cancer cells were used as a model system to study the in vitro fate. These Si-P-CNPs showed improved drug loading, drug effectivity, biodegradability and avoidance of interaction with transforming growth factor ß1 (TGF-ß1) indicating the possibility of reducing the chances of lung fibrosis and thereby enhancing the safety profile over conventional porous silica particles.


Assuntos
Carbono , Curcumina , Portadores de Fármacos , Dióxido de Silício , Fator de Crescimento Transformador beta1 , Dióxido de Silício/química , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/química , Humanos , Porosidade , Portadores de Fármacos/química , Carbono/química , Curcumina/química , Curcumina/farmacologia , Células A549 , Linhagem Celular Tumoral , Fibrose , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia
20.
J Hazard Mater ; 470: 134271, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608593

RESUMO

Rapid and sensitive monitoring of pH and histamine is crucial for bridging biological and food systems and identifying corresponding abnormal situations. Herein, N-doped carbon dots (CDs) are fabricated by a hydrothermal method employing dipicolinic acid and o-phenylenediamine as precursors. The CDs exhibit colorimetric and fluorescent dual-mode responses to track pH and histamine variations in living cells and food freshness, respectively. The aggregation-induced emission enhancement and intramolecular charge transfer result in a decrease in absorbance and an increase in fluorescence, which become readily apparent as the pH changes from acidic to neutral. This property enables precise differentiation between normal and cancerous cells. Furthermore, given the intrinsic basicity of histamine, pH-responsive CDs are advantageous for additional colorimetric and fluorescent monitoring of histamine in food freshness, achieving linearities of 25-1000 µM and 30-1000 µM, respectively, which are broader than those of alternative nanoprobes. Interestingly, the smartphone-integrated sensing platform can portably and visually evaluate pH and histamine changes due to sensitive color changes. Therefore, the sensor not only establishes a dynamic connection between pH and histamine for the purposes of biological and food monitoring, but also presents a novel approach for developing a multifunctional biosensor that can accomplish environmental monitoring and biosensing simultaneously.


Assuntos
Carbono , Colorimetria , Histamina , Pontos Quânticos , Histamina/análise , Carbono/química , Colorimetria/métodos , Concentração de Íons de Hidrogênio , Pontos Quânticos/química , Humanos , Técnicas Biossensoriais/métodos , Espectrometria de Fluorescência , Smartphone , Análise de Alimentos/métodos , Nitrogênio/química , Fluorescência , Corantes Fluorescentes/química
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