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1.
Nanotechnol Sci Appl ; 17: 107-125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645468

RESUMO

Purpose: Biofilms, which are created by most microorganisms, are known for their widely developed drug resistance, even more than planktonic forms of microorganisms. The aim of the study was to assess the effectiveness of agents composed of farnesol and nanoparticles (silver, gold, copper, and zinc oxide) in the degradation of biofilms produced by pathogenic microorganisms. Methods: Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans were used to create the biofilm structure. Colloidal suspensions of silver, gold, copper, and zinc oxide (Ag, Au, Cu, ZnO) with the addition of farnesol (F) were used as the treatment factor. The size distribution of those composites was analyzed, their zeta potential was measured, and their structure was visualized by transmission electron microscopy. The viability of the microorganism strains was assessed by an XTT assay, the ability to form biofilms was analyzed by confocal microscopy, and the changes in biofilm structure were evaluated by scanning electron microscopy. The general toxicity toward the HFFF2 cell line was determined by a neutral red assay and a human inflammation antibody array. Results: The link between the two components (farnesol and nanoparticles) caused mutual stability of both components. Planktonic forms of the microorganisms were the most sensitive when exposed to AgF and CuF; however, the biofilm structure of all microorganism strains was the most disrupted (both inhibition of formation and changes within the structure) after AgF treatment. Composites were not toxic toward the HFFF2 cell line, although the expression of several cytokines was higher than in the not-treated group. Conclusion: The in vitro studies demonstrated antibiofilm properties of composites based on farnesol and nanoparticles. The greatest changes in biofilm structure were triggered by AgF, causing an alteration in the biofilm formation process as well as in the biofilm structure.

2.
Biomed Pharmacother ; 170: 116090, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38169187

RESUMO

PURPOSE: The aim of the study was to evaluate the effect of silver nanoparticles hydrocolloids (AgNPs) on human corneal epithelial cells. Epithelial cells form the outermost and the most vulnerable to environmental stimuli layer of the cornea in the eye. Mechanical stress, UV radiation, and pathogens such as bacteria, viruses, and parasites challenge the fragile homeostasis of the eye. To help combat stress, infection, and inflammation wide portfolio of interventions is available. One of the oldest treatments is colloidal silver. Silver nanoparticle suspension in water is known for its anti-bacterial anti-viral and antiprotozoal action. However, AgNPs interact also with host cells, and the character of the interplay between corneal cells and silver seeks investigation. METHODS: The human epithelial corneal cell line (HCE-2) was cultured in vitro, treated with AgNPs, and subjected to UV. The cell's viability, migration, calcium concentration, and expression/protein level of selected proteins were investigated by appropriate methods including cytotoxicity tests, "wound healing" assay, Fluo8/Fura2 AM staining, qRT-PCR, and western blot. RESULTS: Incubation of human corneal cells (HCE-2) with AgNP did not affect cells viability but limited cells migration and resulted in altered calcium homeostasis, decreased the presence of ATP-activated P2X7, P2Y2 receptors, and enhanced the expression of PACAP. Furthermore, AgNPs pretreatment helped restrain some of the deleterious effects of UV irradiation. Interestingly, AgNPs had no impact on the protein level of ACE2, which is important in light of potential SARS-CoV-2 entrance through the cornea. CONCLUSIONS: Silver nanoparticles are safe for corneal epithelial cells in vitro.


Assuntos
Nanopartículas Metálicas , Prata , Humanos , Prata/metabolismo , Cálcio/metabolismo , Nanopartículas Metálicas/toxicidade , Receptores Purinérgicos P2Y2/metabolismo , Córnea , Células Epiteliais
3.
Nanotechnol Sci Appl ; 16: 41-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111798

RESUMO

Introduction: Disorganisation of the extracellular matrix (ECM) is strongly connected to tumor progression. Even small-scale changes can significantly influence the adhesion and proliferation of cancer cells. Therefore, the use of biocompatible nanomaterials capable of supporting and partially replenishing degraded ECM might be essential to recover the niche after tumor resection. The objective of this study was to evaluate the influence of graphene, graphene oxide, fullerene, and diamond nanofilms on breast cancer and glioblastoma grade IV cell lines. Methods: Nanomaterials were characterized using SEM and TEM techniques; zeta potential analysis was also performed. Nanofilms of graphene, fullerene, and diamond nanoparticles were also characterized using AFM. The toxicity was tested on breast cancer MDA.MB.231 and glioblastoma grade IV U-87 MG cell lines, using LDH assay and by counting stained dead cells in bioprinted 3D models. The following parameters were analyzed: proliferation, adhesion to the nanofilm, and adhesion to particular ECM components covered with diamond nanoparticles. Results and Discussion: Our studies demonstrated that nanofilms of graphene and diamond nanoparticles are characterized by cell-specific toxicity. Those nanomaterials were non-toxic to MDA.MB.231 cells. After applying bioprinted 3D models, diamond nanoparticles were not toxic for both cell lines. Nanofilms made of diamond nanoparticles and graphene inhibit the proliferation of MDA.MB.231 cells after 48 and 72 hours. Increased adhesion on nanofilm made of diamond nanoparticles was only observed for MDA.MB.231 cells after 30 and 60 minutes from seeding the cells. However, analysis of adhesion to certain ECM components coated with diamond nanoparticles revealed enhanced adhesion to tenascin and vitronectin for both tested cell lines. Conclusion: Our studies show that nanofilm made of diamond nanoparticles is a non-toxic and pro-adhesive nanomaterial that might stabilize and partially replenish the niche after breast tumor resection as it enhances the adhesion of breast cancer cells and inhibits their proliferation.

4.
Nanoscale ; 15(46): 18639-18659, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37975795

RESUMO

Nanostructuring is a process involving surface manipulation at the nanometric level, which improves the mechanical and biological properties of biomaterials. Specifically, it affects the mechanotransductive perception of the microenvironment of cells. Mechanical force conversion into an electrical or chemical signal contributes to the induction of a specific cellular response. The relationship between the cells and growth surface induces a biointerface-modifying cytophysiology and consequently a therapeutic effect. In this study, we present the fabrication of graphene oxide (GO)-based nanofilms decorated with metallic nanoparticles (NPs) as potential coatings for biomaterials. Our investigation showed the effect of decorating GO with metallic NPs for the modification of the physicochemical properties of nanostructures in the form of nanoflakes and nanofilms. A comprehensive biocompatibility screening panel revealed no disturbance in the metabolic activity of human fibroblasts (HFFF2) and bone marrow stroma cells (HS-5) cultivated on the GO nanofilms decorated with gold and copper NPs, whereas a significant cytotoxic effect of the GO nanocomplex decorated with silver NPs was demonstrated. The GO nanofilm decorated with gold NPs beneficially managed early cell adhesion as a result of the transient upregulation of α1ß5 integrin expression, acceleration of cellspreading, and formation of elongated filopodia. Additionally, the cells, sensing the substrate derived from the nanocomplex enriched with gold NPs, showed reduced elasticity and altered levels of vimentin expression. In the future, GO nanocomplexes decorated with gold NPs can be incorporated in the structure of architecturally designed biomimetic biomaterials as biocompatible nanostructuring agents with proadhesive properties.


Assuntos
Grafite , Nanopartículas Metálicas , Nanoestruturas , Humanos , Adesão Celular , Nanoestruturas/química , Nanopartículas Metálicas/química , Grafite/farmacologia , Grafite/química , Ouro/farmacologia , Ouro/química , Materiais Biocompatíveis/farmacologia
5.
Int J Nanomedicine ; 18: 4839-4855, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662685

RESUMO

Introduction: Graphene oxide (GO) is a single layer of carbon atoms with unique properties, which are beneficial due to its surface functionalisation by miRNA. miRNAs are a non-coding small form of RNA that suppress the expression of protein-coding genes by translational repression or degradation of messenger RNA. Antisense miRNA-21 is very promising for future investigation in cancer therapy. This study aimed to detect cytokine expression levels after the administration of GO-antisense miRNA-21 into U87, U118, U251 and T98 glioma cell lines. Methods: U87, U118, U251 and T98 glioma cell line were investigated in term of viability, human cytokine expression level at protein and genes after treatment with GO, GO-antisense miRNA-21 and antisense miRNA-21. The delivery of antisense miRNA-21 into the glioma cell at in vitro investigation were conducted by GO based transfection and electroporation. Results: The results of the protein microarray and gene expression profile showed that complexes of GO-antisense miRNA-21 modified the metallopeptidase inhibitor 2 (TIMP-2), interleukin-6 (IL-6), interleukin 8 (IL-8), intercellular adhesion molecule 1 (ICAM-1), and monocyte chemoattractant protein-1 (MCP-1) expression level compared to transfection by electroporation of antisense miRNA-21 at investigated glioblastoma cell lines. The TIMP-2 protein and gene expression level was upregulated after antisense miRNA-21 delivery by GO complex into U87, U251 and T98 glioblastoma cell lines comparing to the non-treated control group. The downregulation at protein expression level of ICAM - 1 was observed at U87, U118, U251 and T98 glioma cell lines. Moreover, the IL-8 expression level at mRNA for genes and protein was decreased significantly after delivery the antisense-miRNA-21 by GO compared to electroporation as a transfection method. Discussion: This work demonstrated that the graphene oxide complexes with antisense miRNA-21 can effectively modulate the cytokine mRNA and protein expression level at U87, U118, U251 and T98 glioma cell lines.


Assuntos
Glioblastoma , Glioma , MicroRNAs , Humanos , Citocinas/genética , Glioblastoma/genética , Glioblastoma/terapia , Interleucina-8/genética , Inibidor Tecidual de Metaloproteinase-2 , Linhagem Celular , MicroRNAs/genética
6.
J Plant Physiol ; 287: 154020, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37301037

RESUMO

Due to their unpredicted scope, duration, and effects, soil droughts pose a serious threat to agriculture. Gradual steppe formation and desertification of farming and horticultural lands are the consequences of climate change. Irrigation systems for field crops do not offer the most viable solution, as they depend heavily on freshwater resources, which are currently scarce. For these reasons, it is necessary to obtain crop cultivars that are not only more tolerant to soil drought, but also capable of effective use of water during and after drought. In this article, we highlight the importance of cell wall-bound phenolics in the efficient adaptation of crops to arid environments and protection of soil water resources.


Assuntos
Agricultura , Conservação dos Recursos Naturais , Solo , Produtos Agrícolas , Parede Celular , Secas
7.
Int J Nanomedicine ; 18: 2821-2838, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37273285

RESUMO

Introduction: Diamond nanoparticles are considered to be one of the most cytocompatible carbon nanomaterials; however, their toxicity varies significantly depending on the analysed cell types. The aim was to investigate the specific sensitivity of endothelial cells to diamond nanoparticles dependent on exposure to nanoparticles. Methods: Diamond nanoparticles were characterized with Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS). Toxicity of diamond nanoparticles was assessed for endothelial cells (HUVEC), human mammary epithelial cells (HMEC) and HS-5 cell line. The effect of diamond nanoparticles on the level of ROS, NO, NADPH and protein synthesis of angiogenesis-related proteins of endothelial cells was evaluated. Results and Discussion: Our studies demonstrated severe cell type-specific toxicity of diamond nanoparticles to endothelial cells (HUVEC) depending on nanoparticle surface interaction with cells. Furthermore, we have assessed the effect on cytotoxicity of the bioconjugation of nanoparticles with a peptide containing the RGD motive and a serum protein corona. Our study suggests that the mechanical interaction of diamond nanoparticles with the endothelial cell membranes and the endocytosis of nanoparticles lead to the depletion of NADPH, resulting in an intensive synthesis of ROS and a decrease in the availability of NO. This leads to severe endothelial toxicity and a change in the protein profile, with changes in major angiogenesis-related proteins, including VEGF, bFGF, ANPT2/TIE-2, and MMP, and the production of stress-related proteins, such as IL-6 and IL-8. Conclusion: We confirmed the presence of a relationship between the toxicity of diamond nanoparticles and the level of cell exposure to nanoparticles and the nanoparticle surface. The results of the study give new insights into the conditioned toxicity of nanomaterials and their use in biomedical applications.


Assuntos
Células Endoteliais , Nanopartículas , Humanos , Células Endoteliais/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NADP , Nanopartículas/toxicidade , Nanopartículas/química , Linhagem Celular
8.
Nanotoxicology ; 17(4): 310-337, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37262345

RESUMO

Reports on the cytotoxicity of diamond nanoparticles (ND) are ambiguous and depend on the physicochemical properties of the material and the tested cell lines. Thus, the aim of this research was to evaluate the influence of thirteen types of diamond nanoparticles, differing in production method, size, and surface functional groups, on their cytotoxicity against four tumor cell lines (T98G, U-118 MG, MCF-7, and Hep G2) and one non-tumor cell line (HFF-1). In order to understand the dependence of diamond nanoparticles on physicochemical properties, the following parameters were analyzed: viability, cell membrane damage, morphology, and the level of intracellular general ROS and mitochondrial superoxide. The performed analyses revealed that all diamond nanoparticles showed no toxicity to MCF-7, Hep G2, and HFF-1 cells. In contrast, the same nanomaterials were moderately toxic for the glioblastoma T98G and U-118 MG cell lines. In general, the effect of the production method did not influence ND toxicity. Some changes in cell response after treatment with modified nanomaterials were observed, with the presence of carboxyl groups having a more detrimental effect than the presence of other functional groups. Although nanoparticles of different sizes caused similar toxicity, nanomaterials with bigger particles caused a more pronounced effect.


Assuntos
Neoplasias da Mama , Carcinoma Hepatocelular , Glioblastoma , Neoplasias Hepáticas , Nanopartículas , Humanos , Feminino , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Glioblastoma/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Nanopartículas/toxicidade , Nanopartículas/química , Linhagem Celular Tumoral , Sobrevivência Celular
9.
Materials (Basel) ; 16(6)2023 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-36984330

RESUMO

This article presents the microstructure, hardness, fracture toughness coefficient KIC and phase composition of submicron WC-4Co carbides. The carbides were sintered using the innovative U-FAST (Upgraded Field Assisted Sintering Technology) method, from mixtures of WC-Co powders with an average WC grain size of 0.4 µm and 0.8 µm. The obtained sinters were characterized by a relative density above 99% of the theoretical density. The hardness of the obtained composites was above 2000 HV30, while the KIC coefficient was about 8 MPa m1/2.

10.
Physiol Plant ; 175(1): e13855, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36648214

RESUMO

The aim was to identify subgenome-related specific responses in two types of triticale, that is, of the wheat-dominated genome (WDG) and rye-dominated genome (RDG), to water stress induced in the early phase (tillering) of plant growth. Higher activity of the primary metabolism of carbohydrates is a feature of the WDG type, while the dominance of the rye genome is associated with a higher activity of the secondary metabolism of phenolic compounds in the RDG type. The study analyzed carbohydrates and key enzymes of their synthesis, free phenolic compounds and carbohydrate-related components of the cell wall, monolignols, and shikimic acid (ShA), which is a key link between the primary and secondary metabolism of phenolic compounds. Under water stress, dominance of the wheat genome in the WDG type was manifested by an increased accumulation of the large subunit of Rubisco and sucrose phosphate synthase and a higher content of raffinose and stachyose compared with the RDG type. In dehydrated RDG plants, higher activity of L-phenylalanine ammonia lyase (PAL) and L-tyrosine ammonia lyase (TAL), as well as a higher level of ShA, free and cell wall-bound p-hydroxybenzoic acid, free homovanillic acid, free sinapic acid, and cell wall-bound syringic acid can be considered biochemical indicators of the dominance of the rye genome.


Assuntos
Desidratação , Fenilalanina Amônia-Liase , Fenilalanina Amônia-Liase/genética , Carboidratos , Plantas/metabolismo , Fenóis/metabolismo
11.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36675285

RESUMO

Plant adaptation to soil drought is a topic that is currently under investigation [...].


Assuntos
Secas , Plantas , Plantas/genética , Estresse Fisiológico , Adaptação Fisiológica
12.
J Exp Bot ; 74(9): 2799-2810, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36124695

RESUMO

Sweet briar (Rosa rubiginosa) belongs to the group of wild roses. Under natural conditions it grows throughout Europe, and was introduced also into the southern hemisphere, where it has efficiently adapted to dry lands. This review focuses on the high adaptation potential of sweet briar to soil drought in the context of global climatic changes, especially considering steppe formation and desertification of agricultural, orchard, and horticultural areas. We provide a comprehensive overview of current knowledge on sweet briar traits associated with drought tolerance and particularly water use efficiency, sugar accumulation, accumulation of CO2 in intercellular spaces, stomatal conductance, gibberellin level, effective electron transport between photosystem II and photosystem I, and protein content. We discuss the genetics and potential applications in plant breeding and suggest future directions of study concerning invasive populations of R. rubiginosa. Finally, we point out that sweet briar can provide new genes for breeding in the context of depleting gene pools of the crop plants.


Assuntos
Rosa , Secas , Melhoramento Vegetal , Plantas , Agricultura
13.
Int J Mol Sci ; 25(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38203729

RESUMO

Ectromelia virus (ECTV) is a causative agent of mousepox. It provides a suitable model for studying the immunobiology of orthopoxviruses, including their interaction with the host cell cytoskeleton. As professional antigen-presenting cells, dendritic cells (DCs) control the pericellular environment, capture antigens, and present them to T lymphocytes after migration to secondary lymphoid organs. Migration of immature DCs is possible due to the presence of specialized adhesion structures, such as podosomes or focal adhesions (FAs). Since assembly and disassembly of adhesive structures are highly associated with DCs' immunoregulatory and migratory functions, we evaluated how ECTV infection targets podosomes and FAs' organization and formation in natural-host bone marrow-derived DCs (BMDC). We found that ECTV induces a rapid dissolution of podosomes at the early stages of infection, accompanied by the development of larger and wider FAs than in uninfected control cells. At later stages of infection, FAs were predominantly observed in long cellular extensions, formed extensively by infected cells. Dissolution of podosomes in ECTV-infected BMDCs was not associated with maturation and increased 2D cell migration in a wound healing assay; however, accelerated transwell migration of ECTV-infected cells towards supernatants derived from LPS-conditioned BMDCs was observed. We suggest that ECTV-induced changes in the spatial organization of adhesive structures in DCs may alter the adhesiveness/migration of DCs during some conditions, e.g., inflammation.


Assuntos
Vírus da Ectromelia , Ectromelia Infecciosa , Animais , Camundongos , Adesivos , Adesividade , Células Dendríticas
14.
Przegl Epidemiol ; 77(3): 302-316, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38329029

RESUMO

The article is an attempt to collect and describe non-medical aspects of the HIV epidemic in Poland in 2023, aspects that often elude epidemiology and treatment specialists. However, they are crucial to public health and, as such, require a presence in the discourse on the broader issue of the HIV epidemic in our country.


Assuntos
Síndrome de Imunodeficiência Adquirida , Epidemias , Infecções por HIV , Humanos , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Síndrome de Imunodeficiência Adquirida/epidemiologia , Polônia/epidemiologia , Saúde Pública
15.
Foods ; 11(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36553688

RESUMO

The aim of the study was to determine the influence of enriching liver sausages with different levels of walnut paste on the quality properties of this product. Sausages were produced with 5, 10, 15, 20, and 25% amount additions of walnut paste and without the addition of nuts (control product). It was found that walnut paste, especially when introduced at an amount >15%, was a component that limited thermal losses and significantly modified the characteristics of liver sausages. The addition of walnut paste also increased the fat content of liver sausages by two−three times, which was one of the factors that weakened their structure, including lowering their compression, shear, and penetration force but increasing their spreadability. Moreover, the addition of walnut paste at an amount of ≥20% resulted in the products having a slightly different color, with lower values for the a* color parameter. Such changes were assessed as a favorable modification to the product, increasing its overall desirability, especially with the addition of walnut paste at the level of 20%. Walnut paste can therefore be a valuable ingredient that allows for the development of a health-promoting product with improved quality features. However, with the addition of a walnut paste at an amount of 25%, it is necessary to take into account the more rapid and unfavorable fat changes that occur during the storage of the liver sausages, as indicated by about 50% higher TBARS values (compared to the control product).

16.
Nucleic Acids Res ; 50(21): 12202-12216, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36420903

RESUMO

Bacterial chromosome topology is controlled by topoisomerases and nucleoid-associated proteins (NAPs). While topoisomerases regulate DNA supercoiling, NAPs introduce bends or coat DNA upon its binding, affecting DNA loop formation. Streptomyces, hyphal, multigenomic bacteria known for producing numerous clinically important compounds, use the highly processive topoisomerase I (TopA) to remove excessive negative DNA supercoils. Elongated vegetative Streptomyces cells contain multiple copies of their linear chromosome, which remain relaxed and relatively evenly distributed. Here, we explored how TopA cooperates with HupA, an HU homologue that is the most abundant Streptomyces NAP. We verified that HupA has an increased affinity for supercoiled DNA in vivo and in vitro. Analysis of mutant strains demonstrated that HupA elimination is detrimental under high DNA supercoiling conditions. The absence of HupA, combined with decreased TopA levels, disrupted chromosome distribution in hyphal cells, eventually inhibiting hyphal growth. We concluded that increased HupA binding to DNA under elevated chromosome supercoiling conditions is critical for the preservation of chromosome organisation.


Assuntos
Streptomyces , Streptomyces/metabolismo , DNA Super-Helicoidal/genética , DNA Topoisomerases Tipo I/metabolismo , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/metabolismo , Replicação do DNA , DNA/genética , DNA Bacteriano/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
17.
Int J Mol Sci ; 23(9)2022 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-35563089

RESUMO

Soil drought is one of the major abiotic stresses that inhibits the growth, development, and yield of crops all over the world [...].


Assuntos
Secas , Estresse Fisiológico , Produtos Agrícolas/fisiologia , Solo , Estresse Fisiológico/fisiologia
18.
Materials (Basel) ; 15(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35591457

RESUMO

The resistance of microorganisms to antibiotics is a crucial problem for which the application of nanomaterials is among a growing number of solutions. The aim of the study was to create a nanocomposite (composed of graphene oxide and silver nanoparticles) with a precise mode of antibacterial action: what enables textiles to be coated in order to exhibit antibacterial properties. A characterization of nanomaterials (silver nanoparticles and graphene oxide) by size distribution, zeta potential measurements, TEM visualization and FT-IR was performed. The biological studies of the nanocomposite and its components included the toxicity effect toward two pathogenic bacteria species, namely Pseudomonas aeruginosa and Staphylococcus aureus, interaction of nanomaterials with the outer layer of microorganisms, and the generation of reactive oxygen species and lipid peroxidation. Afterwards, antibacterial studies of the nanocomposite's coated textiles (cotton, interlining fabric, polypropylene and silk) as well as studies of the general toxicity towards a chicken embryo chorioallantoic membrane model were conducted. The toxicity of the nanocomposite used was higher than its components applied separately (zones of growth inhibition for P. aeruginosa for the final selected concentrations were as follows: silver nanoparticles 21 ± 0.7 mm, graphene oxide 14 ± 1.9 mm and nanocomposite 23 ± 1.6 mm; and for S. aureus were: silver nanoparticles 27 ± 3.8 mm, graphene oxide 14 ± 2.1 mm, and nanocomposite 28 ± 0.4 mm. The viability of P. aeruginosa and S. aureus after treatment with selected GO-Ag decreased to 27% and 31%, respectively, compared to AgNPs, when the viability of both species was 31% and 34%, accordingly). The coated textiles showed encouraging antibacterial features without general toxicity towards the chicken embryo chorioallantoic membrane model. We demonstrated that graphene oxide might constitute a functional platform for silver nanoparticles, improving the antibacterial properties of bare silver. Due to the application of the nanocomposite, the textiles showed promising antibacterial features with a low general toxicity, thereby creating a wide possibility for them to be used in practice.

19.
Ann Bot ; 130(3): 393-408, 2022 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-35294964

RESUMO

BACKGROUND AND AIMS: The study reports on four different types of flag leaf rolling under soil drought in relation to the level of cell wall-bound phenolics. The flag leaf colonization by aphids, as a possible bioindicator of the accumulation of cell wall-bound phenolics, was also estimated. METHODS: The proteins of the photosynthetic apparatus that form its core and are crucial for maintaining its stability (D1/PsbA protein), limit destructive effects of light (PsbS, a protein binding carotenoids in the antennas) and participate in efficient electron transport between photosystems II (PSII) and PSI (Rieske iron-sulfur protein of the cytochrome b6f complex) were evaluated in two types of flag leaf rolling. Additionally, biochemical and physiological reactions to drought stress in rolling and non-rolling flag leaves were compared. KEY RESULTS: The study identified four types of genome-related types of flag leaf rolling. The biochemical basis for these differences was a different number of phenolic molecules incorporated into polycarbohydrate structures of the cell wall. In an extreme case of non-rolling dehydrated flag leaves, they were found to accumulate high amounts of cell wall-bound phenolics that limited cell water loss and protected the photosynthetic apparatus against excessive light. PSII was also additionally protected against excess light by the accumulation of photosynthetic apparatus proteins that ensured stable and efficient transport of excitation energy beyond PSII and its dissipation as far-red fluorescence and heat. Our analysis revealed a new type of flag leaf rolling brought about by an interaction between wheat and rye genomes, and resulting in biochemical specialization of flexible, rolling and rigid, non-rolling parts of the flag leaf. The study confirmed limited aphid colonization of the flag leaves with enhanced content of cell wall-bound phenolics. CONCLUSIONS: Non-rolling leaves developed effective adaptation mechanisms to reduce both water loss and photoinhibitory damage to the photosynthetic apparatus under drought stress.


Assuntos
Secas , Água , Carotenoides/metabolismo , Clorofila/metabolismo , Complexo Citocromos b6f/metabolismo , Biomarcadores Ambientais , Fenóis/metabolismo , Fotossíntese/fisiologia , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/fisiologia , Solo , Água/metabolismo
20.
Biomedicines ; 11(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36672535

RESUMO

Brain-derived neurotrophic factor (BDNF) is a protein affecting survival of existing neurons and neuronal maturation. Patients suffering from several mental disorders exhibit reduced BDNF levels comparing to healthy population. In this systematic review we aim to evaluate the effect of broadly defined cognitive behavioral therapy (CBT) on BDNF levels in psychiatric patients. A literature search was performed using PubMed and Google Scholar data bases. The resources were searched between 14 January and 3 February 2022. Following the inclusion criteria, a total of 10 randomized-controlled trials were included. The results of our research indicate that BDNF levels might be considered an indicator of a result achieved in psychotherapy of cognitive functions. However, no such correlation was observed for mindfulness-based practices intended to lower stress levels or improve the quality of life. It is important to notice that present research showed no consistent correlation between the increase in BDNF levels and the perceived effectiveness of the procedures. Thus, the exact role of BDNF remains unknown, and so far, it cannot be taken as an objective measure of the quality of the interventions.

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