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1.
J Autoimmun ; 145: 103204, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520895

RESUMO

Epidemiological studies show that cardiovascular events related to platelet hyperactivity remain the leading causes of death among multiple sclerosis (MS) patients. Quantitative or structural changes of platelet cytoskeleton alter their morphology and function. Here, we demonstrated, for the first time, the structural changes in MS platelets that may be related to their hyperactivity. MS platelets were found to form large aggregates compared to control platelets. In contrast to the control, the images of overactivated, irregularly shaped MS platelets show changes in the cytoskeleton architecture, fragmented microtubule rings. Furthermore, MS platelets have long and numerous pseudopodia rich in actin filaments. We showed that MS platelets and megakaryocytes, overexpress ß1-tubulin and ß-actin mRNAs and proteins and have altered post-translational modification patterns. Moreover, we identified two previously undisclosed mutations in the gene encoding ß1-tubulin in MS. We propose that the demonstrated structural changes of platelet cytoskeleton enhance their ability to adhere, aggregate, and degranulate fueling the risk of adverse cardiovascular events in MS.


Assuntos
Plaquetas , Proteínas do Citoesqueleto , Citoesqueleto , Esclerose Múltipla , Tubulina (Proteína) , Humanos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/sangue , Plaquetas/metabolismo , Tubulina (Proteína)/metabolismo , Tubulina (Proteína)/genética , Feminino , Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Adulto , Masculino , Pessoa de Meia-Idade , Actinas/metabolismo , Actinas/genética , Megacariócitos/metabolismo , Megacariócitos/patologia , Processamento de Proteína Pós-Traducional , Mutação
2.
Molecules ; 29(20)2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39459204

RESUMO

Outer membrane vesicles (OMVs) are extracellular structures, ranging in size from 10 to 300 nm, produced by Gram-negative bacteria. They can be incorporated into the outer membrane of a recipient's cells, which may enable the transfer of substances with lytic properties. Due to the scarce information regarding the OMVs produced by Proteus mirabilis, the aim of this study was to test the blebbing abilities of the clinical P. mirabilis O77 and O78 strains and to determine the blebs' interactions with bacterial cells, including their possible bactericidal activities. The production of OMVs was visualised by Transmission electron microscopy (TEM). The presence of OMVs in the obtained samples as well as the phenomenon of OMV fusion to recipient cells were confirmed by Enzyme-Linked ImmunoSorbent Assay (ELISA) and Western blotting assays. The bacteriolytic activity of the OMVs was examined against P. mirabilis clinical strains and reference Staphylococcus aureus and Escherichia coli strains. It was shown that each of the two tested P. mirabilis strains could produce OMVs which were able to fuse into the cells of the other strain. The lytic properties of the O78 OMVs against another P. mirabilis O78 strain were also demonstrated. This promising result may help in the future to better understand the mechanisms of the pathogenesis and to treat the infections caused by P. mirabilis.


Assuntos
Membrana Externa Bacteriana , Vesículas Extracelulares , Proteus mirabilis , Proteus mirabilis/metabolismo , Membrana Externa Bacteriana/metabolismo , Vesículas Extracelulares/metabolismo , Escherichia coli/metabolismo , Humanos , Staphylococcus aureus/metabolismo , Bacteriólise , Microscopia Eletrônica de Transmissão
3.
J Sci Food Agric ; 100(7): 2911-2921, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32034777

RESUMO

BACKGROUND: Cherry fruit cracking is a costly problem for cherry growers. The effect of repeated sprayings (gibberellic acid - GA3 ; abscisic acid - ABA; salicylic acid - SA; glycine betaine - GB, and Ascophyllum nodosum - AN) combined with CaCl2 , on 'Sweetheart' cherry fruit-cracking characteristics was investigated. Cracking was quantified in terms of cracking incidence, crack morphology, confocal scanning laser microscopy, cuticular wax content, cell-wall modification, and cuticular wax gene expression. RESULTS: All spray treatments reduced cracking compared with an untreated control (H2 O), with fewer cheek cracks. The least cracking incidence was observed for ABA + CaCl2 - and GB + CaCl2 -treated fruits, indicating an added benefit compared to spraying with CaCl2 alone. In addition, GB + CaCl2 -treated fruits showed higher fruit diameter. ABA + CaCl2 and GB + CaCl2 sprays showed higher wax content and higher cuticle and epidermal thickness compared with the control, including increased expression of wax synthase (ABA + CaCl2 ) and expansin 1 (GB + CaCl2 ). CONCLUSION: In general, factors that improve the cuticle thickness appear to be important at the fruit-coloring stage. At the fruit-ripening stage, larger cell sizes of the epidermis, hypodermis, and parenchyma cells lower cracking incidence, indicating the importance of flexibility and elasticity of the epidermis. © 2020 Society of Chemical Industry.


Assuntos
Frutas/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Prunus avium/efeitos dos fármacos , Cloreto de Cálcio/farmacologia , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Epiderme Vegetal/efeitos dos fármacos , Prunus avium/genética , Prunus avium/fisiologia
4.
Biochim Biophys Acta ; 1848(4): 907-15, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25576765

RESUMO

AIMS: We have investigated the effect of surface charge of model lipid membranes on their interactions with dendriplexes formed by HIV-derived peptides and 2 types of positively charged carbosilane dendrimers (CBD). METHODS: Interaction of dendriplexes with lipid membranes was measured by fluorescence anisotropy, dynamic light scattering and Langmuir-Blodgett techniques. The morphology of the complexes was examined by transmission electron microscopy. RESULTS: All dendriplexes independent of the type of peptide interacted with model lipid membranes. Negatively charged vesicles composed of a mixture of DMPC/DPPG interacted more strongly, and it was accompanied by an increase in anisotropy of the fluorescent probe localized in polar domain of lipid bilayers. There was also an increase in surface pressure of the lipid monolayers. Mixing negatively charged liposomes with dendriplexes increased liposome size and made their surface charges more positive. CONCLUSIONS: HIV-peptide/dendrimer complexes interact with model lipid membranes depending on their surface charge. Carbosilane dendrimers can be useful as non-viral carriers for delivering HIV-peptides into cells.


Assuntos
Dendrímeros/metabolismo , HIV-1/química , Bicamadas Lipídicas/metabolismo , Lipídeos de Membrana/metabolismo , Fragmentos de Peptídeos/metabolismo , Silanos/metabolismo , Dendrímeros/química , Polarização de Fluorescência , Humanos , Interações Hidrofóbicas e Hidrofílicas , Bicamadas Lipídicas/química , Lipossomos , Fluidez de Membrana , Lipídeos de Membrana/química , Microscopia Eletrônica de Transmissão , Fragmentos de Peptídeos/química , Fosfolipídeos/química , Fosfolipídeos/metabolismo , Silanos/química
5.
Physiol Plant ; 154(2): 194-209, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25214438

RESUMO

During their lifetime, plants need to adapt to a changing environment, including light and temperature. To understand how these factors influence plant growth, we investigated the physiological and antioxidant responses of two Arabidopsis accessions, Shahdara (Sha) from the Shahdara valley (Tajikistan, Central Asia) in a mountainous area and Lovvik-5 (Lov-5) from northern Sweden to different light and temperature conditions. These accessions originate from different latitudes and have different life strategies, both of which are known to be influenced by light and temperature. We showed that both accessions grew better in high-light and at a lower temperature (16°C) than in low light and at 23°C. Interestingly, Sha had a lower chlorophyll content but more efficient non-photochemical quenching than Lov-5. Sha, also showed a higher expression of vitamin E biosynthetic genes. We did not observe any difference in the antioxidant prenyllipid level under these conditions. Our results suggest that the mechanisms that keep the plastoquinone (PQ)-pool in more oxidized state could play a role in the adaptation of these accessions to their local climatic conditions.


Assuntos
Antioxidantes/metabolismo , Arabidopsis/fisiologia , Aclimatação , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Arabidopsis/ultraestrutura , Clorofila/metabolismo , Luz , Oxirredução , Folhas de Planta/genética , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Folhas de Planta/ultraestrutura , Plastoquinona/metabolismo , Suécia , Temperatura
6.
Artigo em Inglês | MEDLINE | ID: mdl-39463206

RESUMO

RATIONALE: The literature indicates that nicotine exposure or its discontinuation impair adult hippocampal neurogenesis in rats, though the impact of exercise on this process remains unclear. We have previously shown that disturbances in the number of doublecortin (DCX, a marker of immature neurons)-positive (DCX+) cells in the dentate gyrus (DG) of the hippocampus during nicotine deprivation may contribute to a depression-like state in rats. OBJECTIVES: This study aimed to investigate the effect of running on hippocampal neurogenesis, depression-like symptoms, and drug-seeking behaviour during nicotine deprivation. METHODS: The rats were subjected to nicotine (0.03 mg/kg/inf) self-administration via an increasing schedule of reinforcement. After 21 sessions, the animals entered a 14-day abstinence phase during which they were housed in either standard home cages without wheels, cages equipped with running wheels, or cages with locked wheels. RESULTS: Wheel running increased the number of Ki-67+ and DCX+ cells in the DG of both nicotine-deprived and nicotine-naive rats. Wheel-running exercise evoked an antidepressant effect on abstinence Day 14 but had no effect on nicotine-seeking behaviour on abstinence Day 15 compared to rats with locked-wheel access. CONCLUSIONS: In summary, long-term wheel running positively affected the number of immature neurons in the hippocampus, which corresponded with an antidepressant response in nicotine-weaned rats. One possible mechanism underlying the positive effect of running on the affective state during nicotine cessation may be the reduction in deficits in DCX+ cells in the hippocampus.

7.
Ecotoxicol Environ Saf ; 74(1): 93-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20650531

RESUMO

The effect of exogenously applied 250 µM anthocyanin-rich (ATH-rich) extract from red cabbage leaves on the ultrastructure of Allium cepa root meristematic cells was investigated. The tested extract slightly affected mitochondria, endoplasmic reticulum (ER), Golgi apparatus and vacuoles. In the presence of ATH, 62% of mitochondria converted to condensed type. In addition swollen, circular ER cisternae were sporadically observed. In the ATH-treated roots, one third of Golgi structures was characterized by the reduced number of vesicles. Moreover in 54% of vacuoles, the electron-dense granular and circular material appeared. Additionally, in the cytoplasm, the presence of numerous multivesicular bodies (MVB) was noticed. The observed ultrastructural modifications of mitochondria, and presumably also ER, probably resulted from the ability of an ATH to affect mitochondrial respiratory activity. The other changes in A. cepa root meristematic cell ultrastructure were connected with the transport of exogenously applied ATH into vacuoles. It seems that they are transported from the plasmolemma to the vacuole by multivesicular bodies (MVB), and there trapped by anthocyanic vacuolar inclusions (AVIs). However, none of the observed ultrastructural changes seemed to disturb cell functions, therefore the ATH-rich extract from red cabbage leaves may be regarded as cell-friendly and can be safely used as a detoxifying agent against heavy metal poisoning, as it is more and more often postulated.


Assuntos
Antocianinas/farmacologia , Brassica/química , Cebolas/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Citoplasma/metabolismo , Citoplasma/ultraestrutura , Complexo de Golgi/metabolismo , Complexo de Golgi/ultraestrutura , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Cebolas/metabolismo , Cebolas/ultraestrutura , Folhas de Planta/química , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Vacúolos/metabolismo , Vacúolos/ultraestrutura
8.
Cells ; 10(11)2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34831328

RESUMO

Cerium oxide nanoparticles (CeO2 NPs) and zinc oxide nanoparticles (ZnO NPs) are emerging pollutants that are likely to occur in the contemporary environment. So far, their combined effects on terrestrial plants have not been thoroughly investigated. Obviously, this subject is a challenge for modern ecotoxicology. In this study, Pisum sativum L. plants were exposed to either CeO2 NPs or ZnO NPs alone, or mixtures of these nano-oxides (at two concentrations: 100 and 200 mg/L). The plants were cultivated in hydroponic system for twelve days. The combined effect of NPs was proved by 1D ANOVA augmented by Tukey's post hoc test at p = 0.95. It affected all major plant growth and photosynthesis parameters. Additionally, HR-CS AAS and ICP-OES were used to determine concentrations of Cu, Mn, Fe, Mg, Ca, K, Zn, and Ce in roots and shoots. Treatment of the pea plants with the NPs, either alone or in combination affected the homeostasis of these metals in the plants. CeO2 NPs stimulated the photosynthesis rate, while ZnO NPs prompted stomatal and biochemical limitations. In the mixed ZnO and CeO2 treatments, the latter effects were decreased by CeO2 NPs. These results indicate that free radicals scavenging properties of CeO2 NPs mitigate the toxicity symptoms induced in the plants by ZnO NPs.


Assuntos
Cério/farmacologia , Nanopartículas Metálicas/química , Nutrientes , Fotossíntese , Pisum sativum/fisiologia , Óxido de Zinco/farmacologia , Cério/metabolismo , Pisum sativum/efeitos dos fármacos , Pisum sativum/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Pigmentos Biológicos/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Estômatos de Plantas/efeitos dos fármacos , Estômatos de Plantas/fisiologia , Transpiração Vegetal/efeitos dos fármacos , Ribulosefosfatos/metabolismo , Zinco/metabolismo
9.
Int J Pharm ; 573: 118867, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31765788

RESUMO

Heterofunctionalized gold nanoparticles (AuNPs) were obtained in a one pot reaction of gold precursor with cationic carbosilane dendrons (first to third generations, 1-3G) and (polyethylene)glycol (PEG) ligands in the presence of a reducing agent. The final dendron/PEG proportion on AuNPs depends on the initial dendron/PEG ratio (3/1, 1/1, 1/3) and dendron generation. AuNPs were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), ultraviolet spectroscopy (UV-VIS), thermogravimetric analysis (TGA), nuclear magnetic resonance (1H NMR) and zeta potential (ZP). Several assays have been carried out to determine the relevance of PEG/dendron ratio and dendron generation in the biomedical properties of PEGylated AuNPs and the results have been compared with those obtained for non-PEGylated AuNPs. Finally, analyses of PEG recognition by anti-PEG antibodies were carried out. In general, haemolysis, platelet aggregation and toxicity were reduced after PEGylation of AuNPs, the effect being dependent on dendron generation and dendron/PEG ratio. Dendron generation determines the exposure of PEG ligand and the interaction of this ligand with AuNPs environment. On the other hand, increasing PEG proportion diminishes toxicity but also favors interaction with antibodies.


Assuntos
Dendrímeros/toxicidade , Portadores de Fármacos/toxicidade , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Silanos/toxicidade , Cátions/química , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética/métodos , Química Farmacêutica/métodos , Dendrímeros/química , Portadores de Fármacos/química , Difusão Dinâmica da Luz , Eritrócitos/efeitos dos fármacos , Ouro/química , Células HeLa , Humanos , Leucócitos Mononucleares , Espectroscopia de Ressonância Magnética , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Agregação Plaquetária/efeitos dos fármacos , Polietilenoglicóis/química , Silanos/química , Testes de Toxicidade
10.
Sci Rep ; 9(1): 6248, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000799

RESUMO

The tissue culture of Phaseolus vulgaris has always been considered difficult. Its regenerative capacity and response to culture conditions are highly genotype-dependent and hamper the application of genetic engineering. The objective of this study was to develop a repeatable technique for organogenic bud induction from selected explants of the common bean. Epicotyls and hypocotyls of six cultivars were investigated to determine the effect of the genotype, and four variants of two basal media (Murashige-Skoog and Gamborg) were tested. The composition of these medium variants was based on the published data suggesting the most universal medium compounds that show the advantage of being applicable to different cultivars. As a result, the common bean epicotyls showed undisputed regeneration superiority over the hypocotyls. Moreover, a well-known observation was confirmed, namely that common bean regeneration is cultivar-specific or at least specific to the cluster of related cultivars. However, efficient regeneration was achieved most often when the epicotyls were incubated on the MS or B5 media amended with AgNO3 and BAP. Additionally, the positive synergistic influence of activated charcoal and silver nitrate on bud formation was demonstrated. The highest values of the epicotyl in vitro response for the common bean cultivars could be presented as follows: Czerwona (70.00%) > Goldpantera (58.89%) and Ibiza (58.89%) > Plus (55.56%) > Laponia (50.56%) > Zlota Saxa (46.11%).


Assuntos
Hipocótilo/crescimento & desenvolvimento , Organogênese Vegetal/fisiologia , Phaseolus/fisiologia , Técnicas de Cultura de Tecidos/métodos , Carvão Vegetal , Meios de Cultura/química , Meios de Cultura/farmacologia , Hipocótilo/efeitos dos fármacos , Organogênese Vegetal/efeitos dos fármacos , Phaseolus/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Nitrato de Prata/farmacologia
11.
Protoplasma ; 253(2): 367-77, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25902894

RESUMO

The effects of 50 and 300 mg L(-1) Zn(2+) (50 Zn and 300 Zn) were investigated in Triticum aestivum (cv. Zura) grown hydroponically for 7 days. Although wheat treated with 50 Zn took up relatively high amount of the metal (8,943 and 1,503 mg kg(-1) DW in roots and shoots, respectively), none of the morphological and cytological parameters were changed. After 300 Zn, the metal concentration increased to 32,205 and 5,553 mg kg(-1) DW in roots and shoots, respectively. It was connected with the depletion of shoot and root growth, their fresh and dry weight, water content and mitotic index of root meristematic cells. Microelement contents (Cu, Mn and Fe) after 50 Zn were changed only in roots, while 300 Zn disturbed ion balance in whole plants. The most evident ultrastructural alterations of root meristematic cells caused by both tested Zn(2+) doses included increased vacuolization, accumulation of granular deposits inside vacuoles and cell wall thickening. The effect of 300 Zn on root cell ultrastructure was greater that of 50 Zn. The majority of mitochondria had condensed matrix and swollen cristae, plastids contained plastoglobuli, nucleoli were ring-shaped, thinned down cytoplasm with lipid droplets and swollen endoplasmic reticulum cisternae appeared. In mesophyll cells, 50 Zn caused slight reorganization of chloroplast thylakoids and formation of condensed mitochondria. Three hundred Zn triggered more extensive, but not degenerative, changes: plasmolysis of some cells; chloroplasts with protrusions, changed thylakoid organisation and often large starch grains; irregular, condensed mitochondria. The results indicate that T. aestivum cv. Zura is relatively tolerant to Zn stress.


Assuntos
Plântula/efeitos dos fármacos , Triticum/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia , Zinco/farmacologia , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Meristema/ultraestrutura , Mitose/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/ultraestrutura , Plântula/crescimento & desenvolvimento , Plântula/ultraestrutura , Triticum/crescimento & desenvolvimento , Triticum/ultraestrutura , Vacúolos/efeitos dos fármacos
12.
Metallomics ; 8(12): 1294-1302, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27896349

RESUMO

Silver nanoparticles (AgNPs) are widely used in all branches of industry. However, their mechanisms of action towards moulds have not been studied yet. Thus we conducted this study in which we have used laser desorption/ionization time-of-flight mass spectrometry (LDI-ToF-MS) analysis to determine metabolomic changes, and microscopic analysis (transmission electron microscopy, fluorescent microscopy) to observe changes in mould cells. The AgNP treatment caused the downregulation of 162 (15 ppm) and 284 (62 ppm), and 19 (15 ppm) and 29 (62 ppm) metabolites of Aspergillus niger and Penicillium chrysogenum, respectively. All influenced features were below m/z 600 (mass-to-charge ratio). We have observed silver ions and their clusters (Ag, Ag2, and Ag3) accumulated in the mould mycelium. As well as, mono-silver ion adducts with nucleotide derivatives (Coenzyme A), amino acids (phenylglycine), peptides (LeuSerAlaLeuGlu) and lipids (fatty acids, diacylglycerophosphoglycerols, monoglicerides and glycerophospholipids). The ultrastructure analysis revealed many sever alterations due to the action of AgNPs, such us shortening and condensation of hyphae, ultrastructural reorganisation, cell plasmolysis, increased vacuolisation, numerous membranous structures, collapsed cytoplasm, accumulation of lipid material, condensed mitochondria, disintegration of organelles, nuclear deformation, condensation and fragmentation of chromatin, creation of apoptotic bodies, as well as a new inside cell wall in P. chrysogenum.


Assuntos
Aspergillus niger/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Penicillium chrysogenum/efeitos dos fármacos , Prata/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Microscopia de Fluorescência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Chem Biol Interact ; 222: 135-47, 2014 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-25451571

RESUMO

The development of nanotechnology opens up new ways for biomedical applications of unmodified and modified diamond nanoparticles which are one of the most popular nanomaterials used in biology, biotechnology, medicine, cosmetics and engineering. They have been applied as diagnostic and therapeutic agents because they can be targeted to and localized in cells causing apoptosis and necrosis. The problem of biocompatibility of nanodiamonds at higher concentrations is thus of primary importance. The first step in the modification of DNPs is usually the introduction of hydrogen groups, which can bind other functional groups. The basic method to introduce -OH groups onto nanoparticles is the Fenton reaction. The aim of this study was to compare the effect of unmodified nanodiamond particles and nanoparticles modified by introduction of -OH groups and etoposide onto their surface reaction on human non-small lung cancer cells. A549 cells were incubated with 2-100µg/ml nanopowders and at 0.6-24µg/ml etoposide in the DMEM medium. We observed a decrease of cells viability and generation of reactive oxygen/ nitrogen species in the cells after incubation, estimated by oxidation of H2DCF-DA and DAF-FM-DA. Modified detonation nanoparticles affected also the cellular content of glutathione and activities of main antioxidant enzymes (glutathione peroxidase, glutathione reductase, glutathione S-transferase, superoxide dismutase and catalase). The results of TEM microscopy show changes in cell morphology. These data demonstrate that modified nanoparticles induce oxidative stress in the target cells.


Assuntos
Antioxidantes/metabolismo , Pulmão/metabolismo , Nanodiamantes/efeitos adversos , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Humanos , Pulmão/efeitos dos fármacos , Pulmão/ultraestrutura , Teste de Materiais , Microscopia Eletrônica de Transmissão , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
14.
Chem Biol Interact ; 219: 90-100, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24882084

RESUMO

During the recent years nanodiamonds have been the subject of interest as possible means of targeted delivery of anticancer substances. Detonation nanodiamonds are attractive candidates for intracellular studies due to their synthesis methods, low cost, good biocompatibility and facile surface functionalizability. Our previous study, in which we used nanoparticles obtained by different methods showed the significance of size and way of production of nanodiamonds in their cellular effects. The aim of this study was to check the ability of surface-modified detonation nanodiamonds to reach intracellular compartments without degradation of the surface-conjugated drug or fluorescent marker. In this study we examined the penetration HUVEC-ST and A549 cells by detonation nanodiamonds (grain size <20 nm) modified by adding to, employing four pharmacological inhibitors of endocytosis, using optical, confocal and transmission electron microscopy We discuss the possibilities, the challenges of studying the endocytic pathways involved in cellular uptake of nanoparticles. Our results suggest that fluorescent nanomaterials are very promising for monitoring the intracellular fate of nanodiamonds.


Assuntos
Cromanos/farmacologia , Endocitose/fisiologia , Células Epiteliais/fisiologia , Fluoresceínas/farmacologia , Células Endoteliais da Veia Umbilical Humana/fisiologia , Nanodiamantes/uso terapêutico , Células Epiteliais/ultraestrutura , Células Endoteliais da Veia Umbilical Humana/ultraestrutura , Humanos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Nanodiamantes/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Protoplasma ; 250(2): 601-11, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22895797

RESUMO

The positive influence of anthocyanin (ATH) on toxic metal-treated plant material is well documented; however, it is still not explained if it is caused by changes in element absorption and distribution. Therefore, detailed analysis of the effect of the ATH-rich extract from red cabbage leaves on Pb uptake and localization at morphological, anatomical and ultrastructural level was the goal of this study. Two-day-old adventitious roots of Allium cepa L. (cv. Polanowska) were treated for 2 h with the aqueous solution of Pb(NO3)2 at the concentration of 100 µM with or without preliminary incubation in the anthocyanin-rich extract from Brassica oleracea L. var. capitata rubra leaves (250 µM, 3 h). The red cabbage extract did not change the total Pb uptake but it enhanced the translocation of accumulated metal from roots to shoots. Within the pretreated roots, more Pb was deposited in their basal part and definitely smaller amount of the metal was bound in the apoplast of the outer layers of cortex cells. The ultrastructural analysis (transmission electron microscopy and X-ray microanalysis) revealed that the ATH-rich extract lowered the number of Pb deposits in intracellular spaces, cell wall and cytoplasm of root meristematic cells as well as in such organelles important to cell metabolism as mitochondria, plastids and nucleus. The Pb deposits were preferably localised in those vacuoles where ATH also occurred. This sequestration of Pb in vacuoles is probably responsible for reduction of metal cytotoxicity and consequently could lead to better plant growth.


Assuntos
Antocianinas/farmacologia , Chumbo/metabolismo , Cebolas/efeitos dos fármacos , Cebolas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Microscopia Eletrônica de Transmissão , Cebolas/ultraestrutura , Raízes de Plantas/ultraestrutura
16.
Colloids Surf B Biointerfaces ; 101: 236-42, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010025

RESUMO

Dendrimers have been proposed as new carriers for selected HIV-1 peptides. This paper reports on the complexation behaviour of the three HIV-derived-peptides: Gp160, NH-EIDNYTNTIYTLLEE-COOH; P24, NH-DTINEEAAEW-COOH and Nef, NHGMDDPEREVLEWRFDSRLAF-COOH with second generation cationic carbosilane dendrimers (CBD) branched with carbonsilicon bonds (CBD-CS) or oxygensilicon bonds (CBD-OS). Studies on the formation of complexes between HIV peptides and CBDs by fluorescence polarization, zeta-potential, electrophoresis and transmission electron microscopy have shown that both studied dendrimers form complexes with HIV peptides. At a molar ratio of (2.5-3):1 (dendrimer:peptide), the complexes formed were in the size range of 180-275 nm and with significant positive surface charge. The results suggest that interactions between dendrimers and HIV peptides have electrostatic nature due to the negative charge of peptides backbone and positive charge of dendrimer functional groups. Dendriplex stability depended on the type of studied dendrimers. Time of peptides release from the complexes ranged from 1 (CBD-OS) to ~36 (CBD-CS)h. Basing on the obtained results, we propose that the water-soluble cationic carbosilane dendrimers can be considered for delivery of HIV peptides to dendritic cells.


Assuntos
Dendrímeros/química , HIV-1/química , Peptídeos/química , Silanos/química , Sequência de Aminoácidos , Eletroquímica , Eletroforese em Gel de Poliacrilamida , Polarização de Fluorescência , Indicadores e Reagentes , Microscopia Eletrônica de Transmissão , Tamanho da Partícula
17.
J Plant Physiol ; 169(1): 34-40, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22056070

RESUMO

Changes in phenolics (PhC - phenolic compounds) measured as UV-absorbing compounds (UVAC) and their localization as well as growth, lipid peroxidation (TBARS level) and proline (Pro) level in three-day-old roots of seedlings (T(o) stage) obtained from hydroprimed (H) and hydroprimed with melatonin (H-MEL) seeds after 2 days of chilling (5°C) and 2 days of re-warming were examined. H and H-MEL resulted in inhibition of root growth under optimal conditions, but after re-warming, a positive effect of MEL was noted. The results also showed a positive MEL impact on TBARS level already after chilling and especially after re-warming. Exposure of Vigna radiata seedlings to chilling caused a significant increase in Pro level, especially in H-MEL roots, but after re-warming it drastically decreased. Under chilling stress, accumulation of UVAC also decreased. However, after re-warming it returned to the level observed in the roots grown constantly at 25°C. Even if after re-warming of V. radiata seedlings only slight accumulation of total PhC was observed, phenolic deposits accumulating in the vacuoles of H-MEL roots were completely different from those in the vacuoles of the control and H roots. H-MEL application to the seeds resulted in a significant increase in small granular composite materials, while in the control and H roots, large oval deposits prevailed. Taken together, it is probable that all of these differences were connected with positive effects of MEL on chilled V. radiata seedlings after re-warming.


Assuntos
Antioxidantes/farmacologia , Temperatura Baixa , Fabaceae/efeitos dos fármacos , Melatonina/farmacologia , Fenóis/metabolismo , Sementes/efeitos dos fármacos , Biomarcadores/metabolismo , Temperatura Baixa/efeitos adversos , Fabaceae/crescimento & desenvolvimento , Fabaceae/metabolismo , Temperatura Alta , Peroxidação de Lipídeos/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Pigmentos Biológicos/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Prolina/metabolismo , Sementes/metabolismo , Estresse Fisiológico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
Protoplasma ; 248(2): 353-61, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20625779

RESUMO

The effect of 2-48 h treatment of Lupinus angustifolius L. roots with lead nitrate at the concentration of 10(-4) M on the nucleoli in meristematic cells was investigated. In the lead presence the number of ring-shaped as well as segregated nucleoli increased especially after 12-48 h of treatment, while spindle-shaped nucleoli appeared after 24 h and 48 h. Lead presence also increased the frequency of cells with silver-stained particles in the nucleus and the number of these particles especially from the 12th hour of treatment. It was accompanied by significant decline of nucleolar area. Analysis of these cells in transmission electron microscope confirmed the presence of ring-shaped and segregated nucleoli. Moreover, electron microscopy revealed compact structure nucleoli without granular component. Additionally, one to three oval-shaped fibrillar structures attached to nucleolus or lying free in the nucleoplasm were visible. The possible mechanism of lead toxicity to the nucleolus is briefly discussed.


Assuntos
Nucléolo Celular/efeitos dos fármacos , Chumbo/farmacologia , Lupinus/citologia , Lupinus/efeitos dos fármacos , Meristema/citologia , Meristema/efeitos dos fármacos , Nitratos/farmacologia , Microscopia Eletrônica de Transmissão , Raízes de Plantas/citologia
19.
Ecotoxicol Environ Saf ; 68(3): 343-50, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17416417

RESUMO

The incubation of Allium cepa L. roots in Pb(NO3)2, Cd(NO3)(2)x4H2O or Cr(NO3)(3)x9H2O solution at the concentration of 100 microM lowered the mitotic index (MI) value in meristem by 58%, 39%, 48%, respectively. The proportion of mitotic phases (mainly prophases and telophases) in MI value was also changed. Moreover, mitotic disturbances such as: c-metaphases, sticky and lagging chromosomes, chromosome bridges, binucleate cells, micronuclei, "budding" nuclei and nucleoli partly outside nuclei were induced in the presence of the tested heavy metals, most frequently after Pb treatment. Pre-incubation in the ATH-rich extract from red cabbage leaves caused 2.5%, 1.8% or 1.6% increase in MI value as compared to the meristematic cells of A. cepa L. roots treated only with Cd, Pb, or Cr, respectively. Additionally, the ATH-rich extract was responsible for changing phase index values towards the control level in the material incubated in Pb or Cd. Moreover, the total number of mitotic abnormalities induced by the tested metals was reduced due to the preincubation in the ATH-rich extract, most effectively in the roots treated with Cd (by 2/3) while by half in Cr presence. These data suggest a protective action of the ATH-rich extract from red cabbage leaves against heavy metal toxicity.


Assuntos
Antocianinas/farmacologia , Antimitóticos/toxicidade , Antioxidantes/farmacologia , Brassica , Quelantes/farmacologia , Meristema/efeitos dos fármacos , Metais Pesados/toxicidade , Cebolas/efeitos dos fármacos , Antocianinas/análise , Antimitóticos/metabolismo , Antioxidantes/química , Compostos de Cádmio/toxicidade , Núcleo Celular/efeitos dos fármacos , Quelantes/química , Cromatografia Líquida de Alta Pressão , Compostos de Cromo/toxicidade , Cromossomos de Plantas/efeitos dos fármacos , Chumbo/toxicidade , Meristema/metabolismo , Meristema/ultraestrutura , Metais Pesados/metabolismo , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Mitose/efeitos dos fármacos , Índice Mitótico , Nitratos/toxicidade , Cebolas/metabolismo , Cebolas/ultraestrutura , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta
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