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1.
Physiol Behav ; 277: 114479, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309608

RESUMO

Institutionalized children are often deprived of affective touch. Such tactile deprivation often leads to constant stress, as measured by the levels of salivary cortisol. We report here the impact of an affective touch program, optimized to activate a specific population of unmyelinated mechanosensitive nerves in the skin called c-tactile afferents (CT) on stress resistance. Two populations of children (age 4-10) were recruited: (i) a cohort living in an orphanage and (ii) a fostered cohort. Both groups received the affective touch program daily for 10-15 min for 5-6 weeks. A cohort of age-matched children living in a family environment acted as a control group and did not receive any instructions for tactile stimulation. Salivary cortisol was collected at the beginning (T1) and at the end (T2) of the study in all three groups. For institutionalized and fostered children there was a significant improvement in the level of cortisol (p < 0.0001) between T1 and T2, which is manifested in the balancing cortisol levels: a decrease where it was elevated and an increase, where the critically low level testified to the distress of the child. Balancing cortisol levels is a process of recovery to normal values, which indicates the restoration of neurohumoral mechanisms of stress regulation. The effect of balancing cortisol levels was more pronounced in the group of fostered children compared to the group of orphanage children (p = 0.0326). The children in the control group had no significant differences.


Assuntos
Percepção do Tato , Tato , Criança , Humanos , Pré-Escolar , Tato/fisiologia , Hidrocortisona , Criança Institucionalizada , Percepção do Tato/fisiologia , Pele/inervação
2.
Biotechnol Rep (Amst) ; 40: e00818, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38020727

RESUMO

Biologically active compounds, including polysaccharides isolated from microalgae, have various properties. Although Nannochloropsis spp. have the potential to produce secondary metabolites important for biotechnology, only a small part of the research on these microalgae has focused on their ability to produce polysaccharide fractions. This study aims to evaluate the physicochemical growth factors of Nannochloropsis spp. microalgae, which ensure the maximum accumulation of polysaccharides, as well as to optimize the parameters of polysaccharide extraction. The optimal nutrient medium composition was selected to maximize biomass and polysaccharide accumulation. The significance of selecting the extraction module and extraction temperature regime, as well as the cultivation conditions (temperature and active acidity value) is emphasized. Important chemical components of polysaccharides responsible for their biological activity were identified.

3.
Mol Ther Nucleic Acids ; 32: 267-288, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37090419

RESUMO

Here, we present DNA aptamers capable of specific binding to glial tumor cells in vitro, ex vivo, and in vivo for visualization diagnostics of central nervous system tumors. We selected the aptamers binding specifically to the postoperative human glial primary tumors and not to the healthy brain cells and meningioma, using a modified process of systematic evolution of ligands by exponential enrichment to cells; sequenced and analyzed ssDNA pools using bioinformatic tools and identified the best aptamers by their binding abilities; determined three-dimensional structures of lead aptamers (Gli-55 and Gli-233) with small-angle X-ray scattering and molecular modeling; isolated and identified molecular target proteins of the aptamers by mass spectrometry; the potential binding sites of Gli-233 to the target protein and the role of post-translational modifications were verified by molecular dynamics simulations. The anti-glioma aptamers Gli-233 and Gli-55 were used to detect circulating tumor cells in liquid biopsies. These aptamers were used for in situ, ex vivo tissue staining, histopathological analyses, and fluorescence-guided tumor and PET/CT tumor visualization in mice with xenotransplanted human astrocytoma. The aptamers did not show in vivo toxicity in the preclinical animal study. This study demonstrates the potential applications of aptamers for precise diagnostics and fluorescence-guided surgery of brain tumors.

4.
J Funct Biomater ; 14(4)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37103269

RESUMO

One of the promising novel methods for radical tumor resection at a single-cell level is magneto-mechanical microsurgery (MMM) with magnetic nano- or microdisks modified with cancer-recognizing molecules. A low-frequency alternating magnetic field (AMF) remotely drives and controls the procedure. Here, we present characterization and application of magnetic nanodisks (MNDs) as a surgical instrument ("smart nanoscalpel") at a single-cell level. MNDs with a quasi-dipole three-layer structure (Au/Ni/Au) and DNA aptamer AS42 (AS42-MNDs) on the surface converted magnetic moment into mechanical and destroyed tumor cells. The effectiveness of MMM was analyzed on Ehrlich ascites carcinoma (EAC) cells in vitro and in vivo using sine and square-shaped AMF with frequencies from 1 to 50 Hz with 0.1 to 1 duty-cycle parameters. MMM with the "Nanoscalpel" in a sine-shaped 20 Hz AMF, a rectangular-shaped 10 Hz AMF, and a 0.5 duty cycle was the most effective. A sine-shaped field caused apoptosis, whereas a rectangular-shaped field caused necrosis. Four sessions of MMM with AS42-MNDs significantly reduced the number of cells in the tumor. In contrast, ascites tumors continued to grow in groups of mice and mice treated with MNDs with nonspecific oligonucleotide NO-MND. Thus, applying a "smart nanoscalpel" is practical for the microsurgery of malignant neoplasms.

5.
Dent J (Basel) ; 11(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36826175

RESUMO

Dental implant therapy is a well-accepted treatment modality. Despite good predictability and success in the early stages, the risk of postplacement inflammation in the long-term periods remains an urgent problem. Surgical access and decontamination with chemical and mechanical methods are more effective than antibiotic therapy. The search for the optimal and predictable way for peri-implantitis treatment remains relevant. Here, we evaluated four cleaning methods for their ability to preserve the implant's surface for adequate mesenchymal stem cell adhesion and differentiation. Implants isolated after peri-implantitis were subjected to cleaning with diamond bur; Ti-Ni alloy brush, air-flow, or Er,Cr:YSGG laser and cocultured with mice MSC for five weeks. Dental bur and titanium brushes destroyed the implants' surfaces and prevented MSC attachment. Air-flow and laser minimally affected the dental implant surface microroughness, which was initially designed for good cell adhesion and bone remodeling and to provide full microbial decontamination. Anodized with titanium dioxide and sandblasted with aluminum oxide, acid-etched implants appeared to be better for laser treatment. In implants sandblasted with aluminum oxide, an acid-etched surface better preserves its topology when treated with the air-flow. These cleaning methods minimally affect the implant's surface, so it maintains the capability to absorb osteogenic cells for further division and differentiation.

6.
Psychol Russ ; 16(4): 37-54, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162805

RESUMO

Background: The range of digital technologies that children use from an early age has expanded significantly. Most studies demonstrate that preschoolers now spend substantially longer on digital devices and start using them at a younger age. Finding a solution for this challenge has research merits and relevance, as the data on benefits and harm of early preschoolers' exposure to digital devices is contradictory. This poses a need to determine theoretically sound and practically validated criteria that could guide the duration and quality of children's exposure to the digital environment. Objective: To review studies that contain recommendations on preschoolers' exposure to the digital environment, namely, exposure limits and evidence to justify the limitation of preschoolers' time on digital media. Design: The analysis starts by identifying theoretical foundations that researchers use in their studies of children's behavior in the digital environment. This is followed by an overview of 40 studies that include research papers, official reports, and methodological recommendations made by healthcare and governmental organizations. Results: The review identified the following ground rules for children's exposure to the digital environment: to provide for child's interaction with a digital device, to use educational applications that will develop skills appropriate to the child's age, to ensure mandatory supervision of children's engagement by an adult who limits the exposure according to child's age-related capabilities and creates conditions for active exploration of the real rather than a virtual world. Children's cognitive development suffers the most from passive intake of digital content. Conclusion: The data herein can help to develop strategies to promote healthy and educational engagement of children with digital devices and media; however, the review highlights the insufficiency of psychophysiological research that would make it possible to practically validate the recommendations on the duration of preschoolers' exposure to the digital environment.

7.
Nucleic Acid Ther ; 32(6): 497-506, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35921069

RESUMO

Cisplatin is an effective drug for treating various cancer types. However, it is highly toxic for both healthy and tumor cells. Therefore, there is a need to reduce its therapeutic dose and increase targeted bioavailability. One of the ways to achieve this could be the coating of cisplatin with polysaccharides and specific carriers for targeted delivery. Nucleic acid aptamers could be used as carriers for the specific delivery of medicine to cancer cells. Cisplatin-arabinogalactan-aptamer (Cis-AG-Ap) conjugate was synthesized based on Cis-dichlorodiammineplatinum, Siberian larch arabinogalactan, and aptamer AS-42 specific to heat-shock proteins (HSP) 71 kDa (Hspa8) and HSP 90-beta (Hsp90ab1). The antitumor effect was estimated using ascites and metastatic Ehrlich tumor models. Cis-AG-Ap toxicity was assessed by blood biochemistry on healthy mice. Here, we demonstrated enhanced anticancer activity of Cis-AG-Ap and its specific accumulation in tumor foci. It was shown that targeted delivery allowed a 15-fold reduction in the therapeutic dose of cisplatin and its toxicity. Cis-AG-Ap sufficiently suppressed the growth of Ehrlich's ascites carcinoma, the mass and extent of tumor metastasis in vivo. Arabinogalactan and the aptamers promoted cisplatin efficiency by enhancing its bioavailability. The described strategy could be very promising for targeted anticancer therapy.


Assuntos
Ácidos Nucleicos , Animais , Camundongos , Cisplatino/farmacologia
8.
Children (Basel) ; 9(3)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35327775

RESUMO

BACKGROUND: We analyzed the hypothesis that the vestibular and auditory systems are integrative functions. METHODS: The study involved 383 children (5.5 ± 2.4 years old). We assessed the conduct of auditory information by recording the auditory brain stem response (ABR), post-rotational nystagmus (PRN), and cervical vestibular evoked myogenic potentials (cVEMP), and calculated the integration of the parameters. All procedures were carried out using the JACOBI 4 software package. RESULTS: We have found out that PRN, ABR, and cVEMP represent three different groups of integrative functions, each of which is conditioned by its own integrative mechanism. We have proven that PRN and ABR are associated with age, but no relationship was found between cVEMP and age. CONCLUSION: According to our data, the severity of ABR and PRN depended on age, while cVEMP was not associated with age. The functional immaturity of the child's vestibular system, which probably arose in utero, often becomes apparent only at school when reading and writing must be mastered. These skills require maturity of both the vestibule ocular and vestibule spinal functions of the vestibular system.

9.
Contemp Clin Dent ; 10(4): 637-642, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32792823

RESUMO

AIMS: The aim of this study is to study the colonization of subgingival biofilm (SGB) with periodontopathogenic bacteria species and endothelium-dependent vasodilation in patients with coronary heart disease and concomitant periodontitis. SUBJECTS AND METHODS: Forty-five patients with cardiovascular diseases (CVDs) were examined - 28 women (62%) and 17 men (38%) aged 53-76 years, including 15 patients with acute myocardial infarction (AMI), 15 patients with exertional angina (pectoris), and 15 patients with chronic periodontitis (CP) without CVD. Dental and cardiological health conditions were determined, a biochemical blood test was conducted, endothelium-dependent vasodilation in the brachial artery was measured, and DNA of periodontopathogenic bacteria in SGB was detected. RESULTS: A reliable interrelation between the colonization of SGB with periodontopathogenic bacteria and development of AMI was established. In AMI patients, the frequency of Porphyromonas gingivalis, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans detection was significantly higher than in the group of participants without cardiovascular disease. The presence of P. gingivalis and A. actinomycetemcomitans in patients with CP directly correlated with severity of periodontal tissue destruction. Endothelium-dependent vasodilation in the brachial artery moderately correlated with patient's cardiological condition (r = 0.3284), biochemical markers of atherosclerosis development (r = 0.6465), and frequency of P. intermedia detection in periodontal pockets (r = 0.3828). CONCLUSIONS: Periodontal status in patients with AMI is characterized by unsatisfactory and poor hygiene, increased indices of bleeding on probing, and periodontal pocket depth in comparison to groups of patients with angina pectoris and CP without cardiovascular pathology.

10.
Toxicol Rep ; 6: 74-90, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30581762

RESUMO

The morphotypes of human macrophages (MPh) were studied in the culture on nano-structured biopolymer substrates, made from polyhydroxyalcanoates (PHAs) of five various monomer compositions, followed by the solvent evaporation. Its surface relief, which was further in direct contact with human cells in vitro, was analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). It was shown, that the features of the micro/nano relief depend on the monomeric composition of the polymer substrates. Monocytes (MN) of patients with atherosclerosis and cardiac ischemia, undergoing stenting and conventional anti-atherosclerotic therapy, were harvested prior and after stenting. MN were isolated and cultured, with the transformation into MPh in direct contact with biopolymer culture substrates with different monomer composition and nano-reliefs, and transformed into MPh, in comparison with the same process on standard culture plastic. Sub-populations of cells with characteristic morphology in each phenotypic class were described, and their quantitative ratios for each sample of polymers were counted as an intermediate result in the development of "smart" material for cardiovascular devices. The results obtained allow us to assume, that the processes of MPh differentiation and polarization in vitro depend not only on the features of the micro/nano relief of biopolymer substrates, but also on the initial state of MN in vivo and general response of patients.

11.
Sci Rep ; 7(1): 264, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28325906

RESUMO

Nowadays, spintronics considers magnetic domain walls as a kind of nanodeviсe that demands for switching much less energy in comparison to homogeneous process. We propose and demonstrate a new concept for the light control via electric field applied locally to a magnetic domain wall playing the role of nanodevice. In detail, we charged a 15-µm-thick metallic tip to generate strong non-uniform electric field in the vicinity of the domain wall in the iron garnet film. The electric field influences the domain wall due to flexomagnetoelectric effect and causes the domain wall shift. The resulting displacement of the domain wall is up to 1/3 of domain width and allows to demonstrate a novel type of the electrically controlled magneto-optical shutter. Polarized laser beam focused on the electric-field-driven domain wall was used to demonstrate the concept of a microscale Faraday modulator. We obtained different regimes of the light modulation - linear, nonlinear and tri-stable - for the same domain wall with corresponding controllable displacement features. Such variability to control of domain wall's displacement with spatial scale of about 10 µm makes the proposed concept very promising for nanophotonics and spintronics.

12.
Pest Manag Sci ; 73(5): 925-935, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27447847

RESUMO

BACKGROUND: An important line of research is the development of a new generation of formulations with targeted and controlled release of the pesticide, using matrices made from biodegradable materials. In this study, slow-release formulations of the fungicide tebuconazole (TEB) have been prepared by embedding it into the matrix of poly-3-hydroxybutyrate (P3HB) in the form of films, microgranules and pellets. RESULTS: The average rates of P3HB degradation were determined by the geometry of the formulation, reaching, for 63 days, 0.095-0.116, 0.081-0.083 and 0.030-0.055 mg day-1 for films, microgranules and pellets respectively. The fungicidal activity of P3HB/TEB against the plant pathogen Fusarium moniliforme was compared with that of the commercial formulation Raxil Ultra. A pronounced fungicidal effect of the experimental P3HB/TEB formulations was observed in 2-4 weeks after application, and it was retained for 8 weeks, without affecting significantly the development of soil aboriginal microflora. CONCLUSION: TEB release can be regulated by the process employed to fabricate the formulation and the fungicide loading, and the TEB accumulates in the soil gradually, as the polymer is degraded. The experimental forms of TEB embedded in the slowly degraded P3HB can be used as a basis for developing slow-release fungicide formulations. © 2016 Society of Chemical Industry.


Assuntos
Ecossistema , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Hidroxibutiratos/química , Poliésteres/química , Microbiologia do Solo , Triazóis/química , Triazóis/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo
13.
J Mater Sci Mater Med ; 27(11): 165, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27655431

RESUMO

The present study reports construction of wound dressing materials from degradable natural polymers such as hydroxy derivatives of carboxylic acids (PHAs) and 3-hydroxybutyrate/4-hydroxybutyrate [P(3HB/4HB)] as copolymer. The developed polymer films and electrospun membranes were evaluated for its wound healing properties with Grafts-elastic nonwoven membranes carrying fibroblast cells derived from adipose tissue multipotent mesenchymal stem cells. The efficacy of nonwoven membranes of P(3HB/4HB) carrying the culture of allogenic fibroblasts was assessed against model skin defects in Wistar rats. The morphological, histological and molecular studies revealed the presence of fibroblasts on dressing materials which facilitated wound healing, vascularization and regeneration. Further it was also observed that cells secreted extracellular matrix proteins which formed a layer on the surface of membranes and promoted the migration of epidermal cells from the neighboring tissues surrounding the wound. The wounds under the P(3HB/4HB) membrane carrying cells healed 1.4 times faster than the wounds under the cell-free membrane and 3.5 times faster than the wounds healing under the eschar (control).The complete wound healing process was achieved at Day 14. Thus the study highlights the importance of nonwoven membranes developed from degradable P(3HB/4HB) polymers in reducing inflammation, enhancing angiogenic properties of skin and facilitating better wound healing process.


Assuntos
Ácido 3-Hidroxibutírico/química , Bandagens , Poli-Hidroxialcanoatos/química , Dermatopatias/metabolismo , Pele/patologia , Cicatrização , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Materiais Biocompatíveis/química , Fibroblastos/metabolismo , Teste de Materiais , Membranas Artificiais , Células-Tronco Multipotentes/citologia , Polímeros/química , Ratos , Ratos Wistar , Regeneração , Transplante de Pele , Alicerces Teciduais
14.
Environ Sci Pollut Res Int ; 23(23): 23936-23950, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27628924

RESUMO

Slow-release formulations of the herbicide metribuzin (MET) embedded in the polymer matrix of degradable poly-3-hydroxybutyrate [P(3HB)] in the form of microparticles, films, microgranules, and pellets were developed and tested. The kinetics of polymer degradation, MET release, and accumulation in soil were studied in laboratory soil microecosystems with higher plants. The study shows that MET release can be controlled by using different techniques of constructing formulations and by varying MET loading. MET accumulation in soil occurs gradually, as the polymer is degraded. The average P(3HB) degradation rates were determined by the geometry of the formulation, reaching 0.17, 0.12, 0.04, and 0.05 mg/day after 60 days for microparticles, films, microgranules, and pellets, respectively. The herbicidal activities of P(3HB)/MET formulations and commercial formulation Sencor Ultra were tested on the Agrostis stolonifera and Setaria macrocheata plants. The parameters used to evaluate the herbicidal activity were plant density and the weight of fresh green biomass measured at days 10, 20, and 30 after sowing. All P(3HB)/MET formulations had pronounced herbicidal activity, which varied depending on MET loading and the stage of the experiment. In the early phases of the experiment, the herbicidal effect of P(3HB)/MET formulations with the lowest MET loading (10 %) was comparable with that of the commercial formulation. The herbicidal effect of P(3HB)/MET formulations with higher MET loadings (25 and 50 %) at later stages of the experiment were stronger than the effect of Sencor Ultra.


Assuntos
Herbicidas/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Microbiologia do Solo , Triazinas/metabolismo , Agrostis/efeitos dos fármacos , Preparações de Ação Retardada , Herbicidas/química , Herbicidas/farmacologia , Hidroxibutiratos/química , Hidroxibutiratos/farmacologia , Cinética , Poliésteres/química , Poliésteres/farmacologia , Setaria (Planta)/efeitos dos fármacos , Solo , Triazinas/química , Triazinas/farmacologia
15.
J Environ Sci Health B ; 51(2): 113-125, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26621217

RESUMO

Polymer poly(3-hydroxybutyrate) [P(3HB)] has been used as a matrix in slow-release formulations of the herbicide metribuzin (MET). Physical P(3HB)/MET mixtures in the form of solutions, powders, and emulsions were used to construct different metribuzin formulations (films, granules, pellets, and microparticles). SEM, X-Ray, and DSC proved the stability of these formulations incubated in sterile water in vitro for long periods of time (up to 49 days). Metribuzin release from the polymer matrix has been also studied. By varying the shape of formulations (microparticles, granules, films, and pellets), we were able to control the release time of metribuzin, increasing or decreasing it.

16.
PLoS One ; 9(2): e87551, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24586280

RESUMO

This study investigates kinetic and production parameters of a glucose-utilizing bacterial strain, C. eutrophus B-10646, and its ability to synthesize PHA terpolymers. Optimization of a number of parameters of bacterial culture (cell concentration in the inoculum, physiological activity of the inoculum, determined by the initial intracellular polymer content, and glucose concentration in the culture medium during cultivation) provided cell concentrations and PHA yields reaching 110 g/L and 80%, respectively, under two-stage batch culture conditions. Addition of precursor substrates (valerate, hexanoate, propionate, γ-butyrolactone) to the culture medium enabled synthesis of PHA terpolymers, P(3HB/3HV/4HB) and P(3HB/3HV/3HHx), with different composition and different molar fractions of 3HB, 3HV, 4HB, and 3HHx. Different types of PHA terpolymers synthesized by C. eutrophus B-10646 were used to prepare films, whose physicochemical and physical-mechanical properties were investigated. The properties of PHA terpolymers were significantly different from those of the P3HB homopolymer: they had much lower degrees of crystallinity and lower melting points and thermal decomposition temperatures, with the difference between these temperatures remaining practically unchanged. Films prepared from all PHA terpolymers had higher mechanical strength and elasticity than P3HB films. In spite of dissimilar surface structures, all films prepared from PHA terpolymers facilitated attachment and proliferation of mouse fibroblast NIH 3T3 cells more effectively than polystyrene and the highly crystalline P3HB.


Assuntos
Cupriavidus/crescimento & desenvolvimento , Cupriavidus/metabolismo , Glucose/metabolismo , Polímeros/metabolismo , 4-Butirolactona/metabolismo , Animais , Caproatos/metabolismo , Linhagem Celular , Meios de Cultura/metabolismo , Fibroblastos/metabolismo , Cinética , Camundongos , Células NIH 3T3 , Propionatos/metabolismo , Temperatura , Valeratos/metabolismo
17.
J Biomater Sci Polym Ed ; 25(4): 370-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24295429

RESUMO

In this study, electrospinning was used to prepare ultrafine fibers from PHAs with different chemical compositions: P(3HB) and copolymers: P(3HB-co-4HB), P(3HB-co-3HV), and P(3HB-co-3HHx). The main process parameters that influence ultrafine fiber diameter and properties (polymer concentration, solution feeding rate, working distance, and applied voltage) have been investigated and their effects evaluated. The study revealed electrospinning parameters for the production of high-quality ultrafine fibers and determined which parameters should be varied to tailor the properties of the products. This study is the first to compare biological and physical-mechanical parameters of PHAs with different chemical compositions as dependent upon the fractions of monomers constituting the polymers and ultrafine fiber orientation. Mechanical strength of aligned ultrafine fibers prepared from different PHAs is higher than that of randomly oriented ones; no significant effect of ultrafine fiber orientation on surface properties has been found. None of the fibrous scaffolds produced by electrospinning from PHAs had any adverse effects on attachment, growth, and viability of NIH 3T3 mouse fibroblast cells, and all of them were found to be suitable for tissue engineering applications.


Assuntos
Materiais Biocompatíveis , Poli-Hidroxialcanoatos/química , Poli-Hidroxialcanoatos/síntese química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Adesão Celular , Sobrevivência Celular , Fibroblastos/citologia , Teste de Materiais , Fenômenos Mecânicos , Camundongos , Microscopia Eletrônica de Varredura , Células NIH 3T3 , Polímeros/química , Polímeros/farmacologia , Soluções/química , Engenharia Tecidual/instrumentação
18.
Hum Mol Genet ; 21(18): 4104-14, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22723015

RESUMO

Exposure to the antiepileptic drug valproic acid (VPA) during gestation causes neurofunctional and anatomic deficits in later life. At present, there are little human data on how early neural development is affected by chemicals. We used human embryonic stem cells, differentiating to neuroectodermal precursors, as a model to investigate the modes of action of VPA. Microarray expression profiling, qPCR of specific marker genes, immunostaining and the expression of green fluorescent protein under the control of the promoter of the canonical neural precursor cell marker HES5 were used as readouts. Exposure to VPA resulted in distorted marker gene expression, characterized by a relative increase in NANOG and OCT4 and a reduction in PAX6. A similar response pattern was observed with trichostatin A, a potent and specific histone deacetylase inhibitor (HDACi), but not with several other toxicants. Differentiation markers were disturbed by prolonged, but not by acute treatment with HDACi, and the strongest disturbance of differentiation was observed by toxicant exposure during early neural fate decision. The increased acetylation of histones observed in the presence of HDACi may explain the up-regulation of some genes. However, to understand the down-regulation of PAX6 and the overall complex transcript changes, we examined further epigenetic markers. Alterations in the methylation of lysines 4 and 27 of histone H3 were detected in the promoter region of PAX6 and OCT4. The changes in these activating and silencing histone marks provide a more general mechanistic rational for the regulation of developmentally important genes at non-cytotoxic drug concentrations.


Assuntos
Anormalidades Induzidas por Medicamentos/genética , Células-Tronco Embrionárias/metabolismo , Epigênese Genética/efeitos dos fármacos , Placa Neural/embriologia , Anormalidades Induzidas por Medicamentos/patologia , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células-Tronco Embrionárias/fisiologia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Metilação , Proteína Homeobox Nanog , Placa Neural/patologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/fisiologia , Células Neuroepiteliais/metabolismo , Células Neuroepiteliais/fisiologia , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/genética , Fatores de Transcrição Box Pareados/metabolismo , Análise de Componente Principal , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transcrição Gênica , Transcriptoma , Ácido Valproico/efeitos adversos
19.
Intervirology ; 48(6): 362-71, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16024940

RESUMO

OBJECTIVE: Mycosis fungoides (MF) is the most frequent form of cutaneous T cell lymphoma (CTCL). Human T cell leukemia virus type 1 (HTLV-1) involvement in MF progression is a matter of debate. The goal of the investigation was to search for HTLV-1 markers in a group of MF patients from a nonendemic area to HTLV-1. MATERIALS AND METHODS: Fifty MF patients and 60 healthy donors from Moscow and the Moscow region were examined for HTLV-1 markers by Western blot, PCR, nested PCR, PCR/Southern hybridization, TaqMan real-time PCR and sequencing. RESULTS: Plasma samples from MF patients were repeatedly negative for antibodies to HTLV-1 structural proteins. HTLV-1 tax-related sequences (corresponding to the second exon) were found in blood from 20 of 50 MF patients and in 3 of 5 saliva specimens. Three of 8 sequenced tax-like amplimers were identical and 5 of 8 contained 1-2 substitutions. tax transcripts and antibodies to p40(tax) were detected in some 'PCR-tax'-positive MF patients. Defective HTLV-1 genomes were demonstrated in 2 of 50 MF patients. Phylogenetic analysis of the defective genome 5'-LTR sequence revealed a relationship with HTLV-1a sequences from the transcontinental subgroup of HTLV-1. CONCLUSIONS: HTLV-1 tax-like sequences were revealed in blood and for the first time in saliva from MF patients living in an HTLV-1 nonendemic region. Expression of tax-like sequences was confirmed by both reverse transcription PCR and Western blot.


Assuntos
Sangue/virologia , Genes pX , Anticorpos Anti-HTLV-I/sangue , Vírus Linfotrópico T Tipo 1 Humano/genética , Micose Fungoide/virologia , Saliva/virologia , Neoplasias Cutâneas/virologia , Adulto , Substituição de Aminoácidos , Southern Blotting , Western Blotting , DNA Viral/química , DNA Viral/genética , Vírus Defeituosos , Feminino , Genoma Viral , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Micose Fungoide/imunologia , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Federação Russa , Análise de Sequência de DNA , Neoplasias Cutâneas/imunologia , Sequências Repetidas Terminais/genética
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