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1.
Int J Mol Sci ; 24(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762509

RESUMO

Alkylresorcinols (ARs) are polyphenolic compounds with a wide spectrum of biological activities and are potentially involved in the regulation of host metabolism. The present study aims to establish whether ARs can be produced by the human gut microbiota and to evaluate alterations in content in stool samples as well as metabolic activity of the gut microbiota of C57BL, db/db, and LDLR (-/-) mice according to diet specifications and olivetol (5-n-pentylresorcinol) supplementation to estimate the regulatory potential of ARs. Gas chromatography with mass spectrometric detection was used to quantitatively analyse AR levels in mouse stool samples; faecal microbiota transplantation (FMT) from human donors to germ-free mice was performed to determine whether the intestinal microbiota could produce AR molecules; metagenome sequencing analysis of the mouse gut microbiota followed by reconstruction of its metabolic activity was performed to investigate olivetol's regulatory potential. A significant increase in the amounts of individual members of AR homologues in stool samples was revealed 14 days after FMT. Supplementation of 5-n-Pentylresorcinol to a regular diet influences the amounts of several ARs in the stool of C57BL/6 and LDLR (-/-) but not db/db mice, and caused a significant change in the predicted metabolic activity of the intestinal microbiota of C57BL/6 and LDLR (-/-) but not db/db mice. For the first time, we have shown that several ARs can be produced by the intestinal microbiota. Taking into account the dependence of AR levels in the gut on olivetol supplementation and microbiota metabolic activity, AR can be assumed to be potential quorum-sensing molecules, which also influence gut microbiota composition and host metabolism.

2.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34884843

RESUMO

X-ray photodynamic therapy (XPDT) has been recently considered as an efficient alternative to conventional radiotherapy of malignant tissues. Nanocomposites for XPDT typically consist of two components-a nanophosphor which re-emits X-rays into visible light that in turn is absorbed by the second component, a photosensitizer, for further generation of reactive oxygen species. In this study, BaGdF5 nanophosphors doped with different Eu:Gd ratios in the range from 0.01 to 0.50 were synthesized by the microwave route. According to transmission electron microscopy (TEM), the average size of nanophosphors was ~12 nm. Furthermore, different coatings with amorphous SiO2 and citrates were systematically studied. Micro-CT imaging demonstrated superior X-ray attenuation and sufficient contrast in the liver and the spleen after intravenous injection of citric acid-coated nanoparticles. In case of the SiO2 surface, post-treatment core-shell morphology was verified via TEM and the possibility of tunable shell size was reported. Nitrogen adsorption/desorption analysis revealed mesoporous SiO2 formation characterized by the slit-shaped type of pores that should be accessible for methylene blue photosensitizer molecules. It was shown that SiO2 coating subsequently facilitates methylene blue conjugation and results in the formation of the BaGdF5: 10% Eu3+@SiO2@MB nanocomposite as a promising candidate for application in XPDT.


Assuntos
Bário/química , Európio/química , Gadolínio/química , Nanocompostos/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Cristalografia por Raios X , Células HeLa , Humanos , Nanocompostos/toxicidade , Tamanho da Partícula , Fármacos Fotossensibilizantes/farmacologia , Dióxido de Silício/química , Raios X
3.
Exp Eye Res ; 203: 108394, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33310058

RESUMO

Micro-CT visualization allows reconstruction of eye structures with the resolution of light microscopy and estimation of tissue densities. Moreover, this method excludes damaging procedures and allows further histological staining due to the similar steps in the beginning. We have shown the feasibility of the lab-based micro-CT machine usage for visualization of clinically important compartments of human eye such as trabecular outflow pathway, retina, iris and ciliary body after pre-treatment with iodine in ethanol. We also identified the challenges of applying this contrasting technique to lens, cornea, and retina and proposed alternative staining methods for these tissues. Thereby this work provides a starting point for other studies for imaging of human eyes in normal and pathological conditions using lab-based micro-CT systems.


Assuntos
Enucleação Ocular , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Microtomografia por Raio-X , Câmara Anterior/anatomia & histologia , Câmara Anterior/diagnóstico por imagem , Segmento Anterior do Olho/anatomia & histologia , Segmento Anterior do Olho/diagnóstico por imagem , Estudos de Viabilidade , Humanos , Imageamento Tridimensional , Cristalino/anatomia & histologia , Cristalino/diagnóstico por imagem , Retina/anatomia & histologia , Retina/diagnóstico por imagem
4.
Mol Neurobiol ; 55(6): 4667-4680, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28707074

RESUMO

Presenilins regulate calcium homeostasis in the endoplasmic reticulum, and dysregulation of intracellular calcium has been implicated in the pathogenesis of Alzheimer disease. Elevated presenilin-1 (PS1) holoprotein levels have been detected in postmortem brains of patients carrying familial Alzheimer disease (FAD) PS1 mutations. This study examines the effect of the FAD presenilin mutant that lacks the ninth exon (PS1 ∆E9) and does not undergo endoproteolysis on store-operated calcium (SOC) entry. Significant enhancement of SOC channel activation was detected by electrophysiological measurements in hippocampal neurons with PS1 ∆E9 mutant expression. Here, we show that (i) the hyperactivation of SOC channels is mediated by the STIM1 sensor and can be attenuated by STIM1 knockdown or 2-aminoethoxydiphenyl borate application, (ii) the STIM2 is not involved in pathological changes of SOC entry, (iii) the pathological SOC entry demonstrates properties of both TRPC and Orai subunit composition, and (iiii) transgenic Drosophila flies with PS1 ∆E9 expression in the cholinergic neuron system show short-term memory loss, which can be abolished by 2-aminoethoxydiphenyl borate feeding.


Assuntos
Canais de Cálcio/metabolismo , Hipocampo/citologia , Ativação do Canal Iônico , Mutação/genética , Neurônios/metabolismo , Presenilina-1/genética , Molécula 1 de Interação Estromal/metabolismo , Animais , Animais Geneticamente Modificados , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Neurônios Colinérgicos/metabolismo , Drosophila melanogaster/genética , Técnicas de Silenciamento de Genes , Transtornos da Memória/patologia , Camundongos , Proteínas Mutantes/metabolismo , Proteína ORAI1/metabolismo , Canais de Cátion TRPC/metabolismo
5.
J Environ Radioact ; 160: 102-11, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27156169

RESUMO

Concentrations of cosmogenic beryllium-7((7)Be) and atmospheric aerosols were measured in the atmosphere of the coastal zone of Vladivostok in 2013-2014. The (7)Be concentrations ranged from 0.5 to 4.1 mBq/m(3), with the lowest values in summer and the highest in spring and autumn; the mean value was 2.2 mBq/m(3). Analysis of meteorological data in the synoptic scale showed an inverse correlation with wet deposition rates R = -0.55 (p = 0.0001) and H2O mixing ratio R = -0.49 (p = 0.0001) and a positive with an average maximum height of 120-h backward trajectories of air masses R = 0.65 (p = 0.0001). Angular cluster analysis showed the (7)Be concentration to be dependent on the north-western (R = 0.53, p = 0.001) and eastern winds (R = -0.7, p = 0.0001 for 2013 and R = -0.49, p = 0.002 for 2014). The multiple regression analysis identified five factors in (7)Be concentration: altitudes (b = 0.44), air temperature (b = 0.36), a portion of trajectories in the pacific (North-East direction) cluster (b = -0.32), aerosol concentrations (b = 0.28) and wet precipitation rates (b = -0.24). The model has a good correlation with the data (adjusted R(2) = 0.55). It was found that the direction and height of the air masses trajectories in the lower troposphere strongly influence the concentration of (7)Be.


Assuntos
Poluentes Radioativos do Ar/análise , Berílio/análise , Radioisótopos/análise , Aerossóis/análise , Movimentos do Ar , Atmosfera , Oceanos e Mares , Monitoramento de Radiação , Federação Russa , Estações do Ano
6.
Syst Biol Reprod Med ; 60(2): 98-104, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24304328

RESUMO

Uterine cervical incompetence (UCI) is a pregnancy complication affecting about 10% of the pregnancies in the western world. Studying the etiology of the UCI requires a specific approach adequate for this highly heterogenous syndrome. Oxidative status disorders are associated with various pathologies, including pregnancy complications. As such, general oxidative status profiling is a promising methodology to treat UCI. We aimed at assaying the closely interrelated oxidative status markers in the uterine cervical incompetence patients by means of the systems biology-oriented approach. Chemiluminescent assay, circulating thioredoxin 1 protein, uric acid, and homocysteine level measurements were used to assess the character of the oxidative status regulation in the UCI patients. We found UCI to be associated with the atypical plasma oxidative status deregulation; UCI plasma samples demonstrated lowered proneness to the pro-oxidative processes, and this was not due to the excessive antioxidant activity. There were neither signs of oxidative stress nor destructive pro-oxidant feedforward circuit locking in the UCI group. We also report increased circulating levels of uric acid in the UCI patients.


Assuntos
Estresse Oxidativo , Incompetência do Colo do Útero/metabolismo , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Gravidez , Adulto Jovem
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