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1.
Artif Life ; 30(1): 16-27, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38358121

RESUMO

In the mid-20th century, two new scientific disciplines emerged forcefully: molecular biology and information-communication theory. At the beginning, cross-fertilization was so deep that the term genetic code was universally accepted for describing the meaning of triplets of mRNA (codons) as amino acids. However, today, such synergy has not taken advantage of the vertiginous advances in the two disciplines and presents more challenges than answers. These challenges not only are of great theoretical relevance but also represent unavoidable milestones for next-generation biology: from personalized genetic therapy and diagnosis to Artificial Life to the production of biologically active proteins. Moreover, the matter is intimately connected to a paradigm shift needed in theoretical biology, pioneered a long time ago, that requires combined contributions from disciplines well beyond the biological realm. The use of information as a conceptual metaphor needs to be turned into quantitative and predictive models that can be tested empirically and integrated in a unified view. Successfully achieving these tasks requires a wide multidisciplinary approach, including Artificial Life researchers, to address such an endeavour.


Assuntos
Biologia , Código Genético
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 250: 119387, 2021 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-33422883

RESUMO

The presented study is devoted to the investigation of the micellization-induced liquid-liquid fluctuations in sodium decanoate (NaD) aqueous solutions, based on the vibrational spectroscopic study of NaD and the determination of critical micelle concentration (CMC) of this system. At the same time, we focused on monitoring the effect of the addition of decanol to this system and changing its basic parameters from the point of view of CMC. CMC is an important parameter from a practical point of view and a characteristic feature of each micelle-forming compound. Upon analyzing the spectroscopic data we focus our attention mainly on the intensity and band position variations of both the symmetrical and antisymmetrical vibrational modes of CH2 groups situated in the high-frequency part of the spectrum. The study used normal (non-enhanced) Raman spectroscopy with excitation wavelength 785 nm, surface-enhanced Raman spectroscopy (SERS) on large-scaled gold-coated SERS-active substrates and infrared spectral measurements. The results of spectroscopic measurements were supported by tensiometry and potentiometry.

5.
Oxid Med Cell Longev ; 2020: 7435260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32655773

RESUMO

Corneal alkali burns are potentially blinding injuries. Alkali induces oxidative stress in corneas followed by excessive corneal inflammation, neovascularization, and untransparent scar formation. Molecular hydrogen (H2), a potent reactive oxygen species (ROS) scavenger, suppresses oxidative stress and enables corneal healing when applied on the corneal surface. The purpose of this study was to examine whether the H2 pretreatment of healthy corneas evokes a protective effect against corneal alkali-induced oxidative stress. Rabbit eyes were pretreated with a H2 solution or buffer solution, by drops onto the ocular surface, and the corneas were then burned with 0.25 M NaOH. The results obtained with immunohistochemistry and pachymetry showed that in the corneas of H2-pretreated eyes, slight oxidative stress appeared followed by an increased expression of antioxidant enzymes. When these corneas were postburned with alkali, the alkali-induced oxidative stress was suppressed. This was in contrast to postburned buffer-pretreated corneas, where the oxidative stress was strong. These corneas healed with scar formation and neovascularization, whereas corneas of H2-pretreated eyes healed with restoration of transparency in the majority of cases. Corneal neovascularization was strongly suppressed. Our results suggest that the corneal alkali-induced oxidative stress was reduced via the increased antioxidant capacity of corneal cells against reactive oxygen species (ROS). It is further suggested that the ability of H2 to induce the increase in antioxidant cell capacity is important for eye protection against various diseases or external influences associated with ROS production.


Assuntos
Álcalis/toxicidade , Antioxidantes/metabolismo , Queimaduras Químicas/tratamento farmacológico , Córnea/metabolismo , Queimaduras Oculares/tratamento farmacológico , Hidrogênio/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Animais , Queimaduras Químicas/metabolismo , Queimaduras Químicas/patologia , Córnea/irrigação sanguínea , Córnea/efeitos dos fármacos , Córnea/patologia , Neovascularização da Córnea/prevenção & controle , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Queimaduras Oculares/induzido quimicamente , Queimaduras Oculares/metabolismo , Queimaduras Oculares/patologia , Feminino , Hidrogênio/farmacologia , Coelhos , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/efeitos dos fármacos
6.
Artif Life ; 26(3): 315-326, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32697160

RESUMO

Self-organizing precipitation processes, such as chemical gardens forming biomimetic micro- and nanotubular forms, have the potential to show us new fundamental science to explore, quantify, and understand nonequilibrium physicochemical systems, and shed light on the conditions for life's emergence. The physics and chemistry of these phenomena, due to the assembly of material architectures under a flux of ions, and their exploitation in applications, have recently been termed chemobrionics. Advances in understanding in this area require a combination of expertise in physics, chemistry, mathematical modeling, biology, and nanoengineering, as well as in complex systems and nonlinear and materials sciences, giving rise to this new synergistic discipline of chemobrionics.


Assuntos
Biologia , Biomimética , Química , Engenharia , Pesquisa Interdisciplinar , Origem da Vida , Física , Ciência dos Materiais , Modelos Teóricos , Nanoestruturas
7.
Oxid Med Cell Longev ; 2019: 1857086, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31641422

RESUMO

Our previous research revealed that trehalose, a nonreducing disaccharide of glucose and an important stress responsive factor, proved to have anti-inflammatory, antiapoptotic, and particularly antioxidant properties in UVB-irradiated corneas. Trehalose reduced oxidative stress in corneas induced by UVB irradiation, by means of a decrease in the antioxidant/prooxidant imbalance in the corneal epithelium. In this study, we demonstrate that trehalose of 3% or 6% concentration in eye drops directly decreases oxidative stress in UVB-irradiated corneas, by removing the excessive amount of reactive oxygen species (ROS). Trehalose drops applied on corneas during UVB irradiation once daily for four days resulted in a reduction or even absence of the oxidative stress, DNA damage, and peroxynitrite formation (detected by nitrotyrosine residues), seen in buffer-treated corneas. Furthermore, trehalose treatment applied curatively after repeated irradiation for the subsequent fourteen days led to the renewal of corneal transparency and significant suppression or even absence of neovascularization. This was in contrast to buffer-treated irradiated corneas, where the intracorneal inflammation was developed and the untransparent corneas were vascularized. In conclusion, the treatment of UVB-irradiated corneas with trehalose eye drops removed the excessive amount of ROS in the corneal epithelium, leading to the suppression of oxidative stress and favorable corneal healing. The 6% trehalose showed a higher intensive antioxidant effect.


Assuntos
Córnea/patologia , Córnea/efeitos da radiação , Lesões da Córnea/tratamento farmacológico , Estresse Oxidativo , Trealose/uso terapêutico , Raios Ultravioleta , Cicatrização/efeitos dos fármacos , Animais , Córnea/efeitos dos fármacos , Dano ao DNA , Feminino , Interleucina-1beta/metabolismo , Queratinas/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Coelhos , Reepitelização/efeitos dos fármacos , Reepitelização/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Trealose/farmacologia , Tirosina/análogos & derivados , Tirosina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos da radiação
8.
Stem Cells Int ; 2019: 5909524, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30805009

RESUMO

The wide use of human multipotent mesenchymal stromal cells (MSCs) in clinical trials requires a full-scale safety and identity evaluation of the cellular product and subsequent transportation between research/medical centres. This necessitates the prolonged hypothermic storage of cells prior to application. The development of new, nontoxic, and efficient media, providing high viability and well-preserved therapeutic properties of MSCs during hypothermic storage, is highly relevant for a successful clinical outcome. In this study, a simple and effective trehalose-based solution was developed for the hypothermic storage of human bone marrow MSC suspensions for further clinical applications. Human bone marrow MSCs were stored at 4°C for 24, 48, and 72 hrs in the developed buffered trehalose solution and compared to several research and clinical grade media: Plasma-Lyte® 148, HypoThermosol® FRS, and Ringer's solution. After the storage, the preservation of viability, identity, and therapeutically associated properties of MSCs were assessed. The hypothermic storage of MSCs in the new buffered trehalose solution provided significantly higher MSC recovery rates and ability of cells for attachment and further proliferation, compared to Plasma-Lyte® 148 and Ringer's solution, and was comparable to research-grade HypoThermosol® FRS. There were no differences in the immunophenotype, osteogenic, and adipogenic differentiation and the immunomodulatory properties of MSCs after 72 hrs of cold storage in these solutions. The obtained results together with the confirmed therapeutic properties of trehalose previously described provide sufficient evidence that the developed trehalose medium can be applied as a low-cost and efficient solution for the hypothermic storage of MSC suspensions, with a high potential for translation into clinical practice.

9.
Free Radic Res ; 53(3): 237-247, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30773939

RESUMO

Oxidative stress initiates, accompanies and contributes to the development of several human diseases and injuries, including ocular diseases. Reactive oxygen species (ROS) can generate oxidative stress via excessive ROS production and/or decreased physiologically occurring antioxidants. To replace these weakened antioxidants, substances with effective antioxidant properties are needed in order to suppress oxidative stress and enable healing. Molecular hydrogen (H2) is very suitable for this purpose due to its unique properties. H2 is the only antioxidant that crosses the blood-brain and blood-ocular barriers. It quickly penetrates through tissue due to its small molecular size and effectively removes ROS, mainly hydroxyl radicals and peroxynitrite. Apart from its antioxidant effects, H2 also displays anti-inflammatory, antiapoptotic, cytoprotective and mitohormetic properties. A significant advantage of H2 is its nontoxicity, even when applied at high concentrations. In this review, we present the results of studies utilising H2 in the treatment of ocular diseases involving oxidative stress. These results, obtained in experimental animals as well as in human clinical studies, show that the suppression of oxidative stress by H2 treatment leads to the prevention or improvement of ocular diseases. In severe degenerative diseases, H2 slows disease progression.


Assuntos
Oftalmopatias/tratamento farmacológico , Hidrogênio/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Oftalmopatias/patologia , Humanos , Hidrogênio/farmacologia
10.
J Pharm Sci ; 108(6): 2136-2142, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30721711

RESUMO

Many new therapeutic candidates and active pharmaceutical ingredients (APIs) are poorly soluble in an aqueous environment, resulting in their reduced bioavailability. A promising way of enhancing the release of an API and, thus, its bioavailability seems to be the use of liquid oil marbles (LOMs). An LOM system behaves as a solid form but consists of an oil droplet in which an already dissolved API is encapsulated by a powder. This study aims to optimize the oil/powder combination for the development of such systems. LOMs were successfully prepared for 15 oil/powder combinations, and the following properties were investigated: particle mass fraction, dissolution time, and mechanical stability. Furthermore, the release of API from both LOMs and LOMs encapsulated into gelatine capsules was studied.


Assuntos
Portadores de Fármacos/química , Composição de Medicamentos/métodos , Óleos/química , Água/química , Disponibilidade Biológica , Cápsulas , Química Farmacêutica , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Gelatina/química , Pós , Solubilidade , Fatores de Tempo
11.
Histol Histopathol ; 34(6): 611-618, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30623968

RESUMO

Trehalose, a disaccharide of glucose, is a naturally occurring nontoxic and nonreducing bioactive sugar. Trehalose is synthetized by many organisms when cells are exposed to stressful conditions, including dehydration, heat, oxidation, hypoxia or even anoxia. Although trehalose is not synthesized by mammalian cells, it has recently been demonstrated to have a number of important properties that indicate its utility in humans. Trehalose enables wound healing by protecting cells, especially cell membranes, from oxidative injury and dessication. When the injured cornea is treated with trehalose, corneal inflammation, scar formation and corneal neovascularization are suppressed. In dry eye disease, trehalose decreased cell apoptosis and reduced oxidative, inflammatory and proteolytic activity at the ocular surface. In UVB irradiated cornea, trehalose suppressed photodamage evoked by UVB rays. It decreased the intracorneal inflammation and reduced corneal neovascularization. Trehalose prevented postoperative fibrous scar formation after ocular surgery, such as glaucoma filtration surgery. The non-toxicity of trehalose allows its administration in humans for extended periods and enables its use in various disease states.


Assuntos
Apoptose , Córnea/efeitos dos fármacos , Estresse Oxidativo , Trealose/farmacologia , Cicatrização , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ensaios Clínicos como Assunto , Córnea/efeitos da radiação , Modelos Animais de Doenças , Síndromes do Olho Seco/tratamento farmacológico , Humanos , Oftalmologia , Coelhos , Trealose/química , Raios Ultravioleta
12.
Artif Life ; 24(1): 71-79, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29369709

RESUMO

Protocells are objects that mimic one or several functions of biological cells and may be embodied as solid particles, lipid vesicles, or droplets. Our work is based on using decanol droplets in an aqueous solution of sodium decanoate in the presence of salt. A decanol droplet under such conditions bears many qualitative similarities with living cells, such as the ability to move chemotactically, divide and fuse, or change its shape. This article focuses on the description of a shape-changing process induced by the evaporation of water from the decanoate solution. Under these conditions, the droplets perform complex shape changes, whereby the originally round decanol droplets grow into branching patterns and mimic the growth of appendages in bacteria or axon growth of neuronal cells. We report two outcomes: (i) the morphological changes are reversible, and (ii) multiple protocells avoid contact between each other during the morphological transformation. The importance of these morphological changes in the context of artificial life are discussed.


Assuntos
Células Artificiais/química , Ácidos Decanoicos/química , Álcoois Graxos/química , Gotículas Lipídicas/química , Biologia Sintética , Água/química
13.
Sci Rep ; 7(1): 18017, 2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29269749

RESUMO

The aim of this study is to examine whether molecular hydrogen (H2) is able to reduce oxidative stress after corneal damage induced by UVB irradiation. We previously found that UVB irradiation of the cornea caused the imbalance between the antioxidant and prooxidant enzymes in the corneal epithelium, followed by the imbalance between metalloproteinases and their physiological inhibitors (imbalances in favour of prooxidants and metalloproteinases) contributing to oxidative stress and development of the intracorneal inflammation. Here we investigate the effect of H2 dissolved in PBS in the concentration 0.5 ppm wt/vol, applied on rabbit corneas during UVB irradiation and healing (UVB doses 1.01 J/cm2 once daily for four days). Some irradiated corneas remained untreated or buffer treated. In these corneas the oxidative stress appeared, followed by the excessive inflammation. Malondiladehyde and peroxynitrite expressions were present. The corneas healed with scar formation and neovascularization. In contrast, in H2 treated irradiated corneas oxidative stress was suppressed and malondiladehyde and peroxynitrite expressions were absent. The corneas healed with the restoration of transparency. The study provides the first evidence of the role of H2 in prevention of oxidative and nitrosative stress in UVB irradiated corneas, which may represent a novel prophylactic approach to corneal photodamage.


Assuntos
Córnea/efeitos dos fármacos , Lesões da Córnea/tratamento farmacológico , Hidrogênio/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Raios Ultravioleta , Animais , Córnea/metabolismo , Córnea/efeitos da radiação , Lesões da Córnea/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos da radiação , Ácido Peroxinitroso/metabolismo , Coelhos , Espécies Reativas de Oxigênio/metabolismo
14.
Artif Life ; 23(4): 528-549, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28985113

RESUMO

Liquid droplets are very simple objects present in our everyday life. They are extremely important for many natural phenomena as well as for a broad variety of industrial processes. The conventional research areas in which the droplets are studied include physical chemistry, fluid mechanics, chemical engineering, materials science, and micro- and nanotechnology. Typical studies include phenomena such as condensation and droplet formation, evaporation of droplets, or wetting of surfaces. The present article reviews the recent literature that employs droplets as animated soft matter. It is argued that droplets can be considered as liquid robots possessing some characteristics of living systems, and such properties can be applied to unconventional computing through maze solving or operation in logic gates. In particular, the lifelike properties and behavior of liquid robots, namely (i) movement, (ii) self-division, and (iii) group dynamics, will be discussed.


Assuntos
Movimento , Robótica/instrumentação , Molhabilidade , Engenharia Química , Físico-Química , Hidrodinâmica , Ciência dos Materiais , Microtecnologia , Nanotecnologia
15.
Oxid Med Cell Longev ; 2017: 8906027, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28400915

RESUMO

The aim of this study was to examine the effect of molecular hydrogen (H2) on the healing of alkali-injured cornea. The effects of the solution of H2 in phosphate buffered saline (PBS) or PBS alone topically applied on the alkali-injured rabbit cornea with 0.25 M NaOH were investigated using immunohistochemical and biochemical methods. Central corneal thickness taken as an index of corneal hydration was measured with an ultrasonic pachymeter. Results show that irrigation of the damaged eyes with H2 solution immediately after the injury and then within next five days renewed corneal transparency lost after the injury and reduced corneal hydration increased after the injury to physiological levels within ten days after the injury. In contrast, in injured corneas treated with PBS, the transparency of damaged corneas remained lost and corneal hydration elevated. Later results-on day 20 after the injury-showed that in alkali-injured corneas treated with H2 solution the expression of proinflammatory cytokines, peroxynitrite, detected by nitrotyrosine residues (NT), and malondialdehyde (MDA) expressions were very low or absent compared to PBS treated injured corneas, where NT and MDA expressions were present. In conclusion, H2 solution favorably influenced corneal healing after alkali injury via suppression of oxidative stress.


Assuntos
Lesões da Córnea/etiologia , Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Hidróxido de Sódio/toxicidade , Actinas/metabolismo , Animais , Córnea/metabolismo , Córnea/patologia , Lesões da Córnea/metabolismo , Lesões da Córnea/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Queratina-12/metabolismo , Queratina-3/metabolismo , Malondialdeído/metabolismo , Ácido Peroxinitroso/metabolismo , Coelhos , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Photochem Photobiol ; 92(5): 720-7, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27317620

RESUMO

Tissue inhibitors of metalloproteinases (TIMPs) are the major endogenous regulators of metalloproteinase activity in tissues. TIMPs are able to inhibit activity of all known matrix metalloproteinases (MMPs) and thus participate in controlling extracellular matrix synthesis and degradation. We showed previously elevated expressions of MMPs in the rabbit corneal epithelium upon UVB exposure and suggested that these enzymes might be involved in corneal destruction caused by excessive proteolysis. The aim of this study was to investigate TIMPs in the corneal epithelium after UV irradiation using immunohistochemical and biochemical methods. We found that as compared to control rabbit corneas where relatively high levels of TIMPs were present in the epithelium, repeated irradiation of the cornea with UVB rays (not with UVA rays of similar doses) significantly decreased TIMPs in corneal epithelial cells. The results of this study point to the suggestion that the decrease in TIMPs in the corneal epithelium after UVB irradiation contributes to increased proteolytic activity of MMPs in UVB-irradiated corneal epithelium found previously.


Assuntos
Epitélio Corneano/efeitos da radiação , Metaloproteinases da Matriz/metabolismo , Raios Ultravioleta , Animais , Epitélio Corneano/enzimologia , Imuno-Histoquímica , Metaloproteinases da Matriz/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Reação em Cadeia da Polimerase em Tempo Real
17.
Exp Eye Res ; 147: 128-137, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27181227

RESUMO

In this study we tried to develop a new approach to suppress inflammation and neovascularization in the alkali-injured rabbit cornea. For this reason Cyclosporine A (CsA)-loaded electrospun nanofibers were transferred onto the ocular surface injured with alkali (0.25 N NaOH). Damaged corneas were divided into the following groups: untreated, treated with CsA eye drops, treated with nanofibers drug-free and treated with CsA-loaded nanofibers. Healthy rabbit corneas served as controls. Drug-free nanofibers and CsA-loaded nanofibers were transferred onto the damaged corneal surface immediately after the injury and sutured to conjunctiva. On day five after the injury the nanofibers were removed. The animals from all groups were sacrificed on day twelve after the injury. The extent of the inflammatory reaction and corneal healing were examined macroscopically, immunohistochemically and biochemically. The central corneal thickness was measured using an ultrasonic pachymeter. When compared with untreated injured corneas, injured corneas treated with drug-free nanofibers or injured corneas treated with CsA eye drops, the number of CD3-positive cells (T lymphocytes) and the production of pro-inflammatory cytokines were strongly reduced in corneas treated with CsA-loaded nanofibers, which was associated with the significantly decreased expression of matrix metalloproteinase 9, inducible nitric oxide synthase, vascular endothelial growth factor and active caspase-3. CsA-loaded nanofibers effectively suppressed corneal inflammation and corneal neovascularization. Central corneal thickness restored to levels before injury only in corneas treated with CsA-loaded nanofibers. Corneal transparency was highly restored in these corneas. It is suggested that the beneficial effect of CsA-loaded nanofibers was associated with the continuous release of CsA from nanofibers and continuous affection of damaged cornea by CsA. The suture of nanofibers to conjunctiva and the closed eyes contributed to beneficial corneal healing. This is in contrast to CsA eye drops, which are quickly washed from the ocular surface and the contact of CsA with the damaged cornea was limited. In conclusion, the approach with CsA-loaded nanofibers could represent an effective alternative mode of therapy for corneal chemical burns.


Assuntos
Álcalis/efeitos adversos , Queimaduras Químicas/tratamento farmacológico , Lesões da Córnea/induzido quimicamente , Ciclosporina/uso terapêutico , Queimaduras Oculares/tratamento farmacológico , Imunossupressores/uso terapêutico , Animais , Caspase 3/metabolismo , Lesões da Córnea/metabolismo , Lesões da Córnea/patologia , Neovascularização da Córnea/patologia , Ciclosporina/administração & dosagem , Modelos Animais de Doenças , Queimaduras Oculares/metabolismo , Queimaduras Oculares/patologia , Feminino , Imuno-Histoquímica , Nanofibras , Coelhos , Linfócitos T/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Oxid Med Cell Longev ; 2016: 5843809, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27057279

RESUMO

The aim of this study was to examine whether mesenchymal stem cells (MSCs) and/or corneal limbal epithelial stem cells (LSCs) influence restoration of an antioxidant protective mechanism in the corneal epithelium and renewal of corneal optical properties changed after alkali burns. The injured rabbit corneas (with 0.25 N NaOH) were untreated or treated with nanofiber scaffolds free of stem cells, with nanofiber scaffolds seeded with bone marrow MSCs (BM-MSCs), with adipose tissue MSCs (Ad-MSCs), or with LSCs. On day 15 following the injury, after BM-MSCs or LSCs nanofiber treatment (less after Ad-MSCs treatment) the expression of antioxidant enzymes was restored in the regenerated corneal epithelium and the expressions of matrix metalloproteinase 9 (MMP9), inducible nitric oxide synthase (iNOS), α-smooth muscle actin (α-SMA), transforming growth factor-ß1 (TGF-ß1), and vascular endothelial factor (VEGF) were low. The central corneal thickness (taken as an index of corneal hydration) increased after the injury and returned to levels before the injury. In injured untreated corneas the epithelium was absent and numerous cells revealed the expressions of iNOS, MMP9, α-SMA, TGF-ß1, and VEGF. In conclusion, stem cell treatment accelerated regeneration of the corneal epithelium, restored the antioxidant protective mechanism, and renewed corneal optical properties.


Assuntos
Antioxidantes/uso terapêutico , Queimaduras Químicas/terapia , Epitélio Corneano/patologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Substâncias Protetoras/uso terapêutico , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Álcalis , Animais , Queimaduras Químicas/enzimologia , Queimaduras Químicas/genética , Queimaduras Químicas/patologia , Diferenciação Celular/efeitos dos fármacos , Opacidade da Córnea/complicações , Opacidade da Córnea/terapia , Paquimetria Corneana , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Limbo da Córnea/citologia , Metaloproteinase 9 da Matriz/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Substâncias Protetoras/farmacologia , Coelhos , Superóxido Dismutase/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Langmuir ; 32(19): 4800-5, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27116007

RESUMO

Pattern formation in far-from-equilibrium systems is observed in several disciplines including biology, geophysics, and reaction-diffusion chemistry, comprising both living and nonliving systems. We aim to study such nonequilibrium dynamics on the laboratory scale with materials of simple composition. We present a novel system based on a 1-decanol droplet placed in a solution of alkaline decanoate. Previously, we showed the short time scale behavior of this system, which included chemotaxis and maze solving. Here we explore long time scale dynamics of the system (several hours) when open to the environment. We observe dramatic morphological changes in the droplet including long tentacular structures, and we analyze the morphology of these structures at both the macroscopic and microscopic scales across a large range of initial conditions. Such reproducible morphological changes in simple droplets open a path to the exploration of shape-based effects in larger-scale pattern-formation studies.

20.
Histol Histopathol ; 31(9): 969-80, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26797822

RESUMO

The aim of this study was to examine whether nanofiber scaffolds seeded with rabbit bone marrow mesenchymal stem cells (MSCs nanofibers) transferred onto the damaged corneal surface and covered with cyclosporine A (CsA)-loaded nanofiber scaffolds (CsA nanofibers) enable healing of the rabbit cornea injured with 1N NaOH. The healing of damaged corneas was examined morphologically, immunohistochemically and biochemically on day 24 after the injury. Compared to untreated injured corneas, where corneal ulceration or large corneal thinning or even perforation were developed, injured corneas treated with drug free nanofibers healed without profound disturbances in a majority of cases, although with fibrosis and scar formation. In injured corneas treated with CsA nanofibers or MSCs nanofibers, the development of scar formation was reduced. Best healing results were obtained with a combination of MSCs and CsA nanofibers (MSCs-CsA nanofibers). Corneas healed with highly restored transparency. Neovascularization highly expressed in untreated injured corneas and reduced in corneas treated with CsA nanofibers or MSCs nanofibers, was suppressed in corneas treated with MSCs-CsA nanofibers. The levels of matrix metalloproteinase 9, inducible nitric oxide synthase, interleukin 6, α-smooth muscle actin, tumor growth factor ß and vascular endothelial growth factor were significantly decreased in these corneas as compared to untreated corneas, where the levels of the above mentioned markers were high. In conclusion, MSCs-CsA nanofibers were effective in the treatment of severe alkali-induced corneal injury.


Assuntos
Lesões da Córnea/terapia , Neovascularização da Córnea/prevenção & controle , Ciclosporina/administração & dosagem , Imunossupressores/administração & dosagem , Transplante de Células-Tronco Mesenquimais/métodos , Animais , Cáusticos/toxicidade , Cicatriz/prevenção & controle , Modelos Animais de Doenças , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Nanofibras , Coelhos , Hidróxido de Sódio/toxicidade , Alicerces Teciduais , Cicatrização/efeitos dos fármacos
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