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1.
Biochem Biophys Res Commun ; 733: 150715, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39317113

RESUMO

Post-translational modifications of histones play a crucial role in chromatin structure maintenance and epigenetic regulation. The LiveMIEL (Live-cell Microscopic Imaging of Epigenetic Landscape) method represents a promising approach for tracking histone modifications. It involves visualization of epigenetic modifications using genetically encoded fluorescent sensors and further analysis of the obtained intranuclear patterns by multiparametric image analysis. In this study, we designed three new red fluorescent sensors-MPP8-Red, AF9-Red and DPF3-Red-for live-cell visualization of patterns of H3K9me3, H3K8ac and H3K4me1, respectively. The observed fluorescent patterns were visually distinguishable, and LiveMIEL analysis clearly classified them into three corresponding groups. We propose that these sensors can be used for live-cell dynamic analysis of changes in organization of three epigenetic types of chromatin.

2.
Dev Neurosci ; 46(1): 1-21, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37231803

RESUMO

The genesis of a mature complement of neurons is thought to require, at least in part, precursor cell lineages in which neural progenitors have distinct identities recognized by exclusive expression of one or a few molecular markers. Nevertheless, limited progenitor types distinguished by specific markers and lineal progression through such subclasses cannot easily yield the magnitude of neuronal diversity in most regions of the nervous system. The late Verne Caviness, to whom this edition of Developmental Neuroscience is dedicated, recognized this mismatch. In his pioneering work on the histogenesis of the cerebral cortex, he acknowledged the additional flexibility required to generate multiple classes of cortical projection and interneurons. This flexibility may be accomplished by establishing cell states in which levels rather than binary expression or repression of individual genes vary across each progenitor's shared transcriptome. Such states may reflect local, stochastic signaling via soluble factors or coincidence of cell surface ligand/receptor pairs in subsets of neighboring progenitors. This probabilistic, rather than determined, signaling could modify transcription levels via multiple pathways within an apparently uniform population of progenitors. Progenitor states, therefore, rather than lineal relationships between types may underlie the generation of neuronal diversity in most regions of the nervous system. Moreover, mechanisms that influence variation required for flexible progenitor states may be targets for pathological changes in a broad range of neurodevelopmental disorders, especially those with polygenic origins.


Assuntos
Transtornos do Neurodesenvolvimento , Neurônios , Masculino , Humanos , Neurônios/metabolismo , Córtex Cerebral/metabolismo , Linhagem da Célula/fisiologia , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Transdução de Sinais , Neurogênese/fisiologia , Diferenciação Celular/fisiologia
3.
J Pak Med Assoc ; 73(Suppl 1)(2): S62-S68, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36788393

RESUMO

Oral mesenchymal stem cell populations in humans have been discovered in close vicinity to oral mucosal tissues and both primary (deciduous) and secondary (permanent) teeth. All these different kinds of stem cells have the ability to divide and replenish themselves, however they vary in their gene expression profiles and their capacity to give rise to distinct cell lineages. They all have multipotentiality i.e. chondrogenic, osteogenic, adipogenic, and neurogenic. Due to their relative accessibility, these cell types may form a source of stem cells with substantial potential for application in tissue regeneration. In this review, discoveries outlining stem cell potential are discussed on various aspects as, are their various applications in orthodontics i.e. orthodontic tooth movement, fixing external root resorption, correcting craniofacial anomalies, accelerating craniofacial distraction osteogenesis, recreating the TMJ, and ensuring a stable maxillary expansion.


Assuntos
Células-Tronco Mesenquimais , Ortodontia , Humanos , Dente Decíduo , Diferenciação Celular , Células-Tronco
4.
J Mater Sci Mater Med ; 31(12): 118, 2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33247778

RESUMO

Redox-responsive cationic polymers have gained considerable attention in gene delivery due to low cytotoxicity and spatio-temporal release of DNA into the cells. Here, we reported the synthesis of reducible disulfide conjugated polyethyleneimine (1.8 kDa) (denoted as SS-PEI) and its application to transfer pEGFP-ZNF580 plasmid (pZNF580) into EA.hy926 cell. This reducible SS-PEI polymer was prepared by one-step polycondensation reaction of low molecular weight PEI with bis-(p-nitrophenyl)-3,3'-dithiodipropionate. The SS-PEI successfully condensed pZNF580 into nano-sized complexes (170 ± 1.5 nm to 255 ± 1.6 nm) with zeta potentials of 3 ± 0.4 mV to 17 ± 0.9 mV. The complexes could be triggered to release pZNF580 when exposed to the reducing environment of 5 mM dithiothreitol. Besides, the SS-PEI exhibited low cytotoxicity. In vitro transfection results showed that SS-PEI exhibited good transfection efficiency comparable to PEI25kDa. Thus, the SS-PEI could act as an reducible gene carrier with good transfection efficiency and low cytotoxicity.


Assuntos
Dissulfetos/química , Técnicas de Transferência de Genes , Polietilenoimina/química , Células Cultivadas , DNA/química , Vetores Genéticos/química , Humanos , Oxirredução , Polímeros/química , Fatores de Transcrição/genética , Transfecção/métodos
5.
Int J Phytoremediation ; 21(11): 1098-1103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244330

RESUMO

Biochar is considered a novel soil amendment for cadmium (Cd) stabilization in contaminated soils. A pot experiment was conducted to examine the efficiency of wheat straw and sugarcane bagasse induced biochar on Cd mobility in soil and its bioavailability to spinach in contaminated soil. Soil pH, Cd contents in plant tissues and microbial biomass were examined. Results showed that Cd was significantly decreased by 30.95% and 20.83% with wheat straw and sugarcane bagasse biochar at 2% application rate respectively, relative to the control. Similarly, Cd contents were decreased in plants shoots by 15.41 and 14.33%, while in roots by 48.3 and 35.54%, when wheat straw and sugarcane biochar were added at 2% application rate respectively. Moreover, soil microbial biomass was significantly increased with the application of all biochar types and their applications rates. Finally, wheat straw biochar at 2% application rate can be considered as an effective approach for Cd stabilization in contaminated soils.


Assuntos
Saccharum , Poluentes do Solo , Biodegradação Ambiental , Disponibilidade Biológica , Cádmio , Celulose , Carvão Vegetal , Solo , Spinacia oleracea , Triticum
6.
Artigo em Inglês | MEDLINE | ID: mdl-35668783

RESUMO

The research work presented in this study is mainly concerned with the bioactivity-directed phytochemical and biological evaluation of Persea duthiei. Persea duthiei is a typical medicinal plant used to treat a variety of ailments such as asthma, edema, and bronchitis. Ethyl acetate, n-hexane, n-butanol, and compounds that are soluble in water were used to examine the antibacterial as well as antifungal capacities of the plant. The antibacterial activity of the soluble parts of ethyl acetate and n-hexane against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Bacillus subtilis was high, even though there was no activity against Pseudomonas aeruginosa. Likewise, the n-hexane and ethyl acetate fractions were found to have substantial efficacy against several fungal strains such as Aspergillus flavus, Aspergillus fumigates, Fusarium solani, and Aspergillus niger, but not against Candida glabrata. Among the studied fractions, the ethyl acetate soluble fraction had potent antibacterial activity against all of the tested species. This fraction was submitted to phytochemical analysis utilizing various chromatographic methods for the extraction of various pure components. As a consequence, four compounds were isolated, and their structures were elucidated using various spectroscopic methods such as IR, EIMS, HR-EIMS, 1H-NMR, 13C-NMR, NOESY, COSY, HMBC, and HMQC. Urs-12-en-3ß-ol (α-amyrine) (1), Urs-12-ene-2α-3ß-diol (chamaedrydiol) (2), 3ß-hydroxyurs-12-en-28-aldehyde (ursolic aldehyde) (3), and 12-oleanex-3ß-ol (ß-amyrine) (4) were extracted. Compounds 1, 2, 3, and 4 were examined for antibacterial and antifungal activity and found to have zones of inhibition ranging from 0 to 11 mm against tested bacteria strains and percent inhibition ranging from 0 to 25 percent against fungus strains. Compounds 1 and 4 showed strong efficacy against the investigated fungal species, with a 25% inhibition rate. In the case of antibacterial activity, compounds 4 and 1 showed potent activity with zones of inhibition of 11 mm and 10 mm, respectively. Compounds 2 and 3 were observed to have nonsignificant antimicrobial activity. However, docking studies reflected the complex formation of compound 1 with beta-hydroxyacyl-ACP dehydratase HadAB and S. aureus tyrosyl-tRNA synthetase and compound 2 with topoisomerase II DNA gyrase complex, and they were reported to have antibacterial properties. Similarly, compound 4 was discovered to be well compatible with the lanosterol 14-demethylase (fungal enzyme) and is thus regarded as having antifungal capabilities. Chimera software was used to identify the binding pockets of these complexes. These results indicated that Persea duthiei is a valuable source of medicinal compounds for medication development.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36498365

RESUMO

Arsenic (As) contaminated groundwater is a worldwide concern due to its chronic effects on human health. The objectives of the study were to evaluate natural inexpensive raw laterite (RL) and kaolinite (RK) for their potential use as As sorbents and to understand the As sorption on laterite and kaolinite by employing sorption and kinetic models. Raw laterite and RK were tested for EC, pH, XRF and CEC as basic parameters. Batch sorption and kinetic experiments data were fitted in the sorption (Langmuir and Freundlich) model and kinetic (pseudo-first and pseudo-second order) reaction equations, respectively. Morphological and structural changes were observed in RL and RK samples before and after As saturation by employing FTIR and SEM. The major constituent in RL was Fe and Al oxides while in RK major oxides were silica and Al. The Freundlich sorption model well explained the experimental data, indicating a greater sorption capacity of RL on a hetero-layered surface compared to RK. The kinetic reaction equations showed that equilibrium was achieved after a contact time of 240 min and the adsorption was chemisorption in nature. The RL and RK were found to be effective sorbents for As removal, however, RL showed maximum As adsorption and thus superior in comparison with RK. Structural and morphological characterization reveals the role of Fe and Al oxides in the case of RL, and Al oxides in the case of RK, in the adsorption of As. Hence this study concludes that these naturally occurring inexpensive resources can be used as sorbent agents for As-contaminated drinking water treatment.


Assuntos
Arsênio , Água Subterrânea , Poluentes Químicos da Água , Purificação da Água , Humanos , Arsênio/análise , Cinética , Argila , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Água Subterrânea/química , Adsorção , Minerais , Óxidos
8.
PeerJ ; 8: e8475, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32257630

RESUMO

BACKGROUND: During a preliminary study, effects of 0, 20, 40, and 60 mM NaCl salinity were assessed on germination rate in relation to electrolyte leakage (EL) in sweet pepper. Results explored significant rises in ethylene evolution from seeds having more EL. It was, therefore, hypothesized that excessive ethylene biosynthesis in plants due to salinity stress might be a root cause of low crop productivity. As salicylic acid is one of the potent ethylene inhibitors, thus SA was used to combat effects of ethylene produced under salinity stress of 60 mM NaCl on different physiological and morphological characteristics of sweet pepper. METHODOLOGY: The effect of 0.05, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 mM SA was evaluated on seed germination, growth and yield of sweet pepper cv. Yolo wonder at salinity stress on 60 mM NaCl. Seeds were primed with SA concentrations and incubated till 312 h in an incubator to study germination. Same SA concentrations were sprayed on foliage of plants grown in saline soil (60 mM NaCl). RESULTS: Seeds primed by 0.2 to 0.3 mM SA improved germination rate by 33% due to suppression of ethylene from 3.19 (control) to 2.23-2.70 mg plate-1. Electrolyte leakage reduced to 20.8-21.3% in seeds treated by 0.2-0.3 mM SA compared to 39.9% in untreated seeds. Results also explored that seed priming by 0.3 mM improved TSS, SOD and chlorophyll contents from 13.7 to 15.0 mg g-1 FW, 4.64 to 5.38 activity h-1 100 mg-1 and 89 to 102 ug g-1 compared to untreated seeds, respectively. Results also explore that SA up to 0.2 mM SA applied on plant foliage improved LAI (5-13%), photosynthesis (4-27%), WUE (11-57%), dry weight (5-20%), SOD activity (4-20%) and finally fruit yield (4-20%) compared to untreated plants by ameliorating effect of 60 mM NaCl. Foliar application of SA also caused significant increase in nutrient use efficiency due to significant variations in POD and SOD activities. CONCLUSION: Salicylic acid suppressed ethylene evolution from germinating seeds up to 30% under stress of 60 mM NaCl due to elevated levels of TSS and SOD activity. Foliar application of SA upgraded SOD by lowering POD activity to improve NUE particularly K use efficiency at salinity stress of 60 mM NaCl. Application of 0.2 and 0.3 mM SA emerged as the most effective concentrations of SA for mitigating 60 mM NaCl stress on different physiological and morphological characteristics of sweet pepper.

9.
Eur J Mass Spectrom (Chichester) ; 25(4): 391-396, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30939934

RESUMO

Investigation of the archeological material at the molecular level can reveal the composition of ancient paint, balsamic material, reveal cooking recipes, etc. High-resolution mass spectrometry is a powerful technique with underestimated potential for archeology. Here, we present the investigation of the 3000-year-old archeological remains, identified as parts of internal organs of an Egyptian mummy, using high-resolution Orbitrap mass spectrometry. We observed a diverse number of oxidized classes of compounds: O, O2, O3, O4, O5, N, NO, NO2, NO3, NO4, NO5, N2O, N2O2. Such chemical composition is unusual and we never observed it in our previous studies of petroleum, humic substances, products of wood pyrolysis or other natural complex mixtures. It is possible that such compounds are formed via biodegradation of lipids and other organic material used for funeral rites. We did not observe evidence of the presence of mineral bitumen, although there are many historical records of the use of mineral bitumen for mummification.

10.
J Mater Chem B ; 7(11): 1893-1905, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-32255052

RESUMO

Gene therapy is concerned with the transfer of complement genes to functionally defective cells in a safe and directed manner for the treatment of the most challenging diseases. But safety issues and low transfection efficiency of the gene vectors are the major challenges, which need to be overcome. Recently, redox-responsive bioreducible polymers containing disulfide linkages have been considered as efficient gene vectors, owing to the selective degradation of the disulfide bond in the reducing environment of the cells. This enables spatiotemporal release of pDNA with no or minimum toxicity. Herein, we reported a bioreducible poly(ethyleneglycol)-b-poly(disulfide-l-lysine) cationic polymer (denoted as PEG-SSL) via a Michael addition reaction of poly(ethyleneglycol)tetraacrylate PEG(Ac)4 and the terminal amine group of poly(disulfide-l-lysine). PEG-SSL efficiently condensed the plasmid ZNF580 gene (pZNF580) forming nano-sized polyplexes (155 ± 4 to 285 ± 3 nm) with zeta potentials of 1.9 ± 0.1 to 26.7 ± 0.4 mV. PEG-SSL successfully retarded pZNF580 at a small polymer/pDNA weight ratio of 10/1 and higher. When exposed to a reducing environment of 5 mM DTT, it rapidly released genes even at higher weight ratios of the PEG-SSL polymer in the PEG-SSL/pDNA complexes. The PEG-SSL/pZNF580 complexes exhibited good stability when exposed to DNase I and efficiently protected pDNA from degradation. In vitro transfection and cytotoxicity were investigated in EA.hy926 cells. The results showed that PEG-SSL successfully delivered pZNF580 into the cells with less cytotoxicity compared to PEI25kDa. The flow cytometry and confocal scanning laser microscopy results indicated that PEG-SSL polyplexes exhibited good cellular uptake and nuclear co-localization rates. All these results implied that PEG-SSL had the potential as a non-viral vector for gene transfection.


Assuntos
Terapia Genética/métodos , Vetores Genéticos , Transfecção/métodos , Linhagem Celular , Dissulfetos/química , Vetores Genéticos/síntese química , Vetores Genéticos/química , Humanos , Lisina/química , Plasmídeos , Polietilenoglicóis/química , Fatores de Transcrição/genética
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