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1.
Int J Mol Sci ; 24(18)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37762190

RESUMO

In recent research, there has been a growing awareness of the role of genetic factors in the positioning and eruption of teeth in the maxilla and mandible. This study aimed to evaluate the potential of specific polymorphic markers of single nucleotide polymorphisms (SNPs) located within the PAX9, MSX1, AXIN2, and IRF6 genes to determine the predisposition to tooth impaction. The study participants were divided into two groups: the first group consisted of individuals with at least one impacted secondary tooth. In contrast, the second group (control group) had no impacted teeth in their jaws. To analyze the genes, real-time PCR (polymerase chain reaction) and TaqMan probes were utilized to detect the selected polymorphisms. The findings suggest that disruptions in the structure and function of the mentioned genetic factors such as polymorphic and haplotype variants of PAX9, MSX1, AXIN2, and IRF6 genes, which play a direct role in tooth and periodontal tissue development, might be significant factors in tooth impaction in individuals with genetic variations. Therefore, it is reasonable to hypothesize that tooth impaction may be influenced, at least in part, by the presence of specific genetic markers, including different allelic variants of the PAX9, AXIN2, and IRF6 genes, and especially MSX1.

2.
BMC Microbiol ; 16: 59, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27044351

RESUMO

BACKGROUND: Low-copy-number vectors of potential wide application in biotechnology need to encode stabilization modules ensuring their stable inheritance. The efficiency of stabilization may vary depending on the plasmid host so a thorough analysis of stabilization functions is required before use. RESULTS: To facilitate such analysis highly unstable, mobilizable, broad-host-range (BHR) vectors based on RK2 replicon were constructed. The vectors are suitable for testing of various stabilization functions, including plasmid and chromosomal partitioning cassettes encoding ParB homologues capable of spreading on DNA. The xylE or lacZ reporter systems facilitate easy monitoring of plasmid segregation. CONCLUSION: The range of BHR vectors with different reporter cassettes and alternative mobilization systems expands their application in diverse bacterial species.


Assuntos
Bactérias/genética , Vetores Genéticos , Plasmídeos/genética , Proteínas de Bactérias/genética , Fatores R , Replicon
3.
Front Biosci (Landmark Ed) ; 28(10): 269, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37919085

RESUMO

Ischemic stroke is one of the major causes of death and disability. Since the currently used treatment option of reperfusion therapy has several limitations, ongoing research is focusing on the neuroprotective effects of microglia and stem cells. By exerting the bystander effect, secreting exosomes and forming biobridges, mesenchymal stem cells (MSCs), neural stem cells (NSCs), induced pluripotent stem cells (iPSCs), and multilineage-differentiating stress-enduring cells (Muse cells) have been shown to stimulate neurogenesis, angiogenesis, cell migration, and reduce neuroinflammation. Exosome-based therapy is now being extensively researched due to its many advantageous properties over cell therapy, such as lower immunogenicity, no risk of blood vessel occlusion, and ease of storage and modification. However, although preclinical studies have shown promising therapeutic outcomes, clinical trials have been associated with several translational challenges. This review explores the therapeutic effects of preconditioned microglia as well as various factors secreted in stem cell-derived extracellular vesicles with their mechanisms of action explained. Furthermore, an overview of preclinical and clinical studies is presented, explaining the main challenges of microglia and stem cell therapies, and providing potential solutions. In particular, a highlight is the use of novel stem cell therapy of Muse cells, which bypasses many of the conventional stem cell limitations. The paper concludes with suggestions for directions in future neuroprotective research.


Assuntos
AVC Isquêmico , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Humanos , Microglia , Acidente Vascular Cerebral/terapia , Alprostadil
4.
J Pept Sci ; 18(3): 192-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22252914

RESUMO

The utility of three various analytical techniques [ion chromatography (IC), capillary electrophoresis (CE) and isotachophoresis (ITP)] was tested in the determination of counter-ions in synthetic peptides. The analyzed ions were acetates, trifluoroacetates and chlorides. IC provided the best results; CE, except limit of detection and limit of quantification, exhibited the comparable results. ITP was classified as the less useful because of the problem with the determination of the chloride ions. Nevertheless, all the three techniques were able to analyze trifluoroacetates and acetates ions with satisfactory results. Except analytical methods, three procedures using hydrochloric acid (HCl) (at two different concentrations) and acetic acid as sample solvents processed by lyophilization were tested. It has been found that the lyophilization not only by HCl but also by acetic acid is a simple and cheap procedure for removal of toxic trifluoroacetic counter-ions from peptides on satisfactory levels.


Assuntos
Técnicas de Química Analítica , Íons/análise , Peptídeos/análise , Acetatos , Cloretos , Cromatografia , Eletroforese Capilar , Liofilização , Isotacoforese , Peptídeos/síntese química , Ácido Trifluoracético
5.
J Sep Sci ; 33(13): 1991-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20533350

RESUMO

Simple, selective and sensitive isotachophoretic methods for the analysis of ionic liquid (IL) compartments were developed in this study. A leading electrolyte containing 10 mM L-histidine + 10 mM histidine hydrochloride and a terminating electrolyte containing 5 mM glutamic acid + 5 mM L-histidine were selected to separate nitrate(V), chlorate(V), hexafluorophosphate, dicyanimide, trifluoromethanesulfonate, phosphate(V) and bis(trifluoromethanesulfonyl)imide in anionic mode. In contrast, seven short-chain alkylimidazolium, alkylpyrrolidinium, alkylpyridinium and non-chromophoric tetraalkylammonium and tetraalkylphosphonium IL cations were separated with 10 mM potassium hydroxide + 10 mM acetic acid as leading electrolyte, and 10 mM beta-alanine + 10 mM acetate as terminating electrolyte. Both methods were optimized and validated with good analytical performance parameters. LOD was about 3-5 microM, and the repeatability lay in the range of 1.06-5.59%. These methods were evaluated for their applicability to the analysis of soil samples and freshwater contaminated with ILs. In light of hitherto the absence of reports on the determination of non-chromophoric IL cations, this study delivers for the first time a universal method enabling analysis of these species. Moreover, as there is still significant lack of methodologies of IL anion analysis, the obtained results offer an interesting alternative in that matter.

6.
Molecules ; 14(11): 4396-405, 2009 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-19924073

RESUMO

Ionic liquids (ILs) are known to be non-volatile and thus to have low potential for atmospheric contamination or intoxication of humans by inhalation. However ILs have the potential to contaminate soil and water as they might be water soluble and can be sorbed onto solids. The investigation of possible natural ways of reducing the concentration of ILs in the environment is of high importance, especially because the requirement for biodegradable chemicals increases, together with pressure for reduction of incineration and landfill waste. It was found that the upper concentration threshold for primary biodegradation of 1-methyl-3-octylimidazolium chloride is 0.2 mM. At higher concentrations the dehydrogenase activity of the cells dropped markedly, indicating that the IL inhibits cell activity. This concentration is in good agreement with the minimal inhibitory concentration of the same compound found for a series of bacteria and fungi by this research group. The sorption of 1-methyl-3-octylimidazolium chloride was found to be significant, and the sorption coefficient was determined to be 98.2 L kg(-1).


Assuntos
Biodegradação Ambiental , Compostos de Piridínio/metabolismo , Esgotos/microbiologia , Poluentes Químicos da Água/metabolismo , Líquidos Iônicos/química
7.
J Microbiol Methods ; 88(1): 53-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22056795

RESUMO

Novel vectors for cloning and shuffling of gene cassettes based on minireplicon of broad-host-range RA3 plasmid from IncU incompatibility group were constructed. A series of minireplicon variants were prepared with copy number ranging from low (1-2 copies per chromosome), medium (10-15 copies per chromosome) to high copy number (80-90 copies per chromosome). The new cloning vectors are relatively small in size (4.5-5.4kb) and carry various resistance determinants: kanamycin (Km(R)), tetracycline (Tc(R)) or chloramphenicol (Cm(R)). The vectors were engineered to facilitate cloning and shuffling of the functional modules with or without transcriptional terminators. Using the described strategy, a bank of functional modules, ready for exchange, has been initiated.


Assuntos
Bactérias/genética , Clonagem Molecular/métodos , Vetores Genéticos/genética , Plasmídeos/genética , Escherichia coli/genética , Dosagem de Genes , Especificidade da Espécie
8.
Chemosphere ; 74(4): 515-21, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19027928

RESUMO

Ionic liquids (ILs) are nowadays emerging as alternative green solvents for various technological applications. In this context, their environmental impacts need to be assessed, and relatively simple and reproducible analytical techniques are required in order to do this. These must be applicable not only to different natural matrices but also to the very low concentrations likely to be present in environmental systems. Moreover, in the case of solid environmental samples, liquid-solid extraction procedures are prerequisite for gaining further insight into IL distribution in these matrices. This paper reports on extraction methods for isolating IL residues from a number of plants, seeds and soils. The efficiency of five organic and inorganic acids in these extractions ranged from 70.2% to 83.5%, depending on the matrix and acid used. IL recovery rates were highest for phosphoric and trifluoroacetic acids. Recoveries of alkylimidazolium IL from all the plant matrices increased with alkyl chain length. The inference from this study is that IL polarity and steric hindrance both influence the mechanism of their sorption onto the plant matrix, which has a significant impact on the extraction efficiency. Saturated ammonium chloride mixed with a large quantity of methanol was the most effective solvent for extracting soil-bound ILs. The extraction efficiency is inversely proportional to the distribution coefficients of particular soils: the higher the value of K(d), the lower the recovery rate. Both methods of extraction were validated for their analytical performance parameters.


Assuntos
Monitoramento Ambiental , Líquidos Iônicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Líquidos Iônicos/análise , Líquidos Iônicos/química , Plantas/química , Poaceae/química , Reprodutibilidade dos Testes , Secale/química , Poluentes do Solo/análise , Solanum tuberosum/química , Solventes/química , Espectrometria de Massas por Ionização por Electrospray
9.
Anal Sci ; 24(10): 1359-61, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18845901

RESUMO

The usefulness of a cation exchange system followed by conductometric detection for alkylimidazolium cations separation and analysis was found for the first time. Furthermore, the possibility of simultaneously separating cations and anions typically used in ionic liquids in one chromatographic run was tested. A tandem of columns containing silica-based strong anion exchange and strong cation exchange packings was used. The study's objective was to find the optimal mobile phase: the best results were obtained with one consisting of potassium hydrogen phthalate and phthalic acid modified with acetonitrile. The method is simple and selective, and is believed to be applicable to numerous ionic liquids based on a similar design.

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