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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 196: 344-352, 2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-29475183

RESUMO

Dimethyl sulfoxide (DMSO) is one of the most versatile solvents in biological science, therefore it is frequently used as a solvent in biological studies and as a vehicle for drug therapy. DMSO readily penetrates, diffuses through biological membranes and ipso facto increases fluidity of liposomal membranes modelling stratum corneum. Thermal injury is associated with the appearance of lipid peroxidation products in the burned skin. The influence of DMSO on protein structure and stability is concentration and temperature dependant. The aim of this study was to assess the impact of DMSO on human burn wounds and examine the interactions between DMSO and skin surface. The real problem in burn treatment is hypoalbuminemia. At the level of the laboratory studies there was an attempt at answering the question of whether the DMSO will modify the standard serum solution. In the case of the incubation of skin fragments in 1%-100% DMSO, the following findings were reported: modification of the serum, appearance of low molecular weight oligomer bands, disappearance of albumin bands or reconstruction of native serum bands during incubation in antioxidant solutions. The result of the modification is also the exposure of FTIR 1603 and 1046cm-1 bands observed in frozen serum solutions. In the case of modification of the burned skin by DMSO solutions or antioxidants - frequency shifts, an increase in the intensity of amide I band as well as the appearance of the 1601cm-1 band can be specific biomarkers of the tissue regeneration process. In this study the areas 1780-1580cm-1 and 1418-1250cm-1 on the Raman spectra are particularly rich in spectral information.


Assuntos
Queimaduras/patologia , Dimetil Sulfóxido/farmacologia , Pele/efeitos dos fármacos , Pele/patologia , Animais , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Humanos , Masculino , Modelos Biológicos , Pele/química , Pele/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 185: 279-285, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28591686

RESUMO

Wound treatment and healing is complex and is comprised of an elaborate set of processes including cellular, spectroscopic and biochemical ones as well as the "reaction" of local tissue to thermal injury. Vitamin C as l-ascorbic acid (LA) prevents injurious effects of oxidants because it reduces reactive oxygen species to stable molecules, it becomes oxidized to the short-lived ascorbyl radical. As a result, antioxidant treatment may contribute to minimizing injury in burn patients. The aim of this study is to assess changes in molecular structure of collagen extracted from human epidermis burn wound scab during incubation of the epidermis in l-ascorbic acid solution. The study will be performed using FTIR and FT Raman spectroscopies. During this research it was observed that the intensity of Raman peaks increased where healing was being modified by LA. The intensity of the amide III band at 1247cm-1 relative to the intensity at 1326cm-1 was used to test tissue repair degree at the incision site. FTIR spectra were recorded from frozen specimens of serum modified by LA; an analysis of shifts in the amide I band position was conducted. The appearance of a new band for frozen samples modified by LA was observed around 1149-1220cm-1. The above conclusions confirmed the creation of hydrogen bonds between NH stretch and CO. Samples being incubated in solutions of l-ascorbic acid demonstrated the absence of electrophoretic bands of albumin. Alterations in the surface of the skin incubated in l-ascorbic acid were investigated with the use of Scanning Electron Microscopy (SEM). A decrease in external symptoms of burn injury was noted in the damaged epidermis incubated in l-ascorbic acid.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Queimaduras/patologia , Pele , Administração Tópica , Idoso , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Colágeno/química , Colágeno/efeitos dos fármacos , Colágeno/ultraestrutura , Eletroforese em Acetato de Celulose , Feminino , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Modelos Biológicos , Pele/química , Pele/efeitos dos fármacos , Pele/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas de Cultura de Tecidos
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 173: 924-930, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27835852

RESUMO

Being a complex traumatic event, burn injury also affects other organ systems apart from the skin. Wounds undergo various pathological changes which are accompanied by alterations in the molecular environment. Information about molecules may be obtained with the use of Raman spectroscopy and Fourier-transform infrared spectroscopy, and when combined, both methods are a powerful tool for providing material characterization. Alterations in the molecular environment may lead to identifying objective markers of acute wound healing. In general, incubation of samples in solutions of l-ascorbic acid and 5% and 7% orthosilicic acid organizes the collagen structure, whereas the increased intensity of the Raman bands in the region of 1500-800cm-1 reveals regeneration of the burn tissue. Since oxidative damage is one of the mechanisms responsible for local and distant pathophysiological events after burn, antioxidant therapy can prove to be beneficial in minimizing burn wounds, which was examined on the basis of human skin samples and chicken skin samples, the latter being subject to modification when heated to a temperature sufficient for the simulation of a burn incident.


Assuntos
Antioxidantes/farmacologia , Queimaduras , Pele , Cicatrização/efeitos dos fármacos , Animais , Queimaduras/tratamento farmacológico , Queimaduras/metabolismo , Queimaduras/patologia , Galinhas , Humanos , Pele/metabolismo , Pele/patologia , Espectrofotometria Infravermelho , Análise Espectral Raman
4.
Electrophoresis ; 35(15): 2237-44, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24853731

RESUMO

Non-enzymatic glycation (Maillard reaction) in vitro could be a simple method to obtain glycoconjugates for studying their biological properties. Hence, fucoidan was retained by acetate electrophoresis indicating a strong interaction with the protein. A loss of colour in fucoidan bands was found for samples incubated with collagen as compared with samples of free fucoidan. Also under in vitro conditions at 100°C - simulating a sudden burn incident - fucoidan binds with collagen as a result of the Maillard reaction. In contrast, the colour of the fucoidan bands intensified for samples incubated with collagen, with the addition of glucose. Electrophoretic analyses were carried out after heating the samples to a temperature simulating a burn incident. The bands were found to intensify for samples incubated with collagen during a 30-day-long incubation. Thus, spontaneous in vitro glycation - i.e. without the addition of glucose - was confirmed. This process is highly intensified both by the temperature and time of incubation. For a sample incubated in vitro in a fucoidan solution containing glucose, glycation was confirmed in a preliminary FTIR and acetate electrophoresis examinations, occurring in collagen obtained from chicken skins. In particular, a new band emerging around 1746 cm(-1) was observed for above samples, as was its increasing intensity, as compared with samples without the addition of glucose. In the collagen glycation assay, while glucose reacts with collagen and forms cross-linked aggregates, fucoidan decreases the process of aggregation and recovery of native collagen.


Assuntos
Acetatos/química , Colágeno/química , Colágeno/metabolismo , Eletroforese/métodos , Polissacarídeos/química , Polissacarídeos/metabolismo , Animais , Galinhas , Colágeno/análise , Glicosilação/efeitos dos fármacos , Reação de Maillard , Polissacarídeos/farmacologia , Pele/química , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Polim Med ; 42(2): 115-20, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-23016442

RESUMO

BACKGROUND: Active dressings (biomaterials, hydrogels) are cross-linked three-dimensional macromolecular networks. One of the most important properties of active dressings, is their ability for controlled uptake, release and retention of molecules. The formation of advanced glycation end products AGEs progressively increases with normal aging. However, AGE products are formed at accelerated rates in age and stress-related diseases (burns, in wound healing) and also in vitro. OBJECTIVES: The aim will be also to develop a series of gels showing ability of controlled uptake, release and retention of molecules. The hydrogels can be used as biologically and therapeutically (antibacterial and anticancer) active biomaterials. MATERIAL AND METHODS: The following materials and reagents were used in the examination: dried plants: Equisetum arvense L., Pulmonaria officinalis L., Agropyron repens. Non-defatted films were extracted from the dried plants. The suspension was stirred and extracted. Temperature was controlled using a water bath. The filtrate was vacuum condensed. The gelling precipitate was poured onto Petri plates and dried. The swelling ratio and the percent loading were calculated. The released amount of CaCl2 at different time intervals was determined by measuring the conductivity. The extent of glycation in collagen was measured. RESULTS AND CONCLUSIONS: Novel types of swelling hydrogels have been prepared from dried plants and alginic acid. The active dressings showed swelling in aqueous medium, swelling characteristics were dependent on the chemical composition of hydrogel. The hydrogels were also loaded with CaCl2 and their potential for release was judged by measuring conductivity. The activity of hydrogels--active dressings on collagen incubated with glucose showed an decrease in glycation. So, hydrogels--active dressings, a known antiglycating agent which have therapeutic role in wound healing.


Assuntos
Bandagens , Materiais Biocompatíveis , Colágeno/química , Hidrogéis/síntese química , Extratos Vegetais/química , Reagentes de Ligações Cruzadas/química , Sistemas de Liberação de Medicamentos , Glicosilação , Hidrogéis/química
6.
Polim Med ; 42(1): 69-77, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-22783735

RESUMO

BACKGROUND: The formation of AGEs progressively increases with normal aging, even in the absence of disease (the pathogenesis of diabetes associated vascular disorders and neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease). However, they are formed at accelerated rates in age-related diseases. The polysaccharides might play a role in wound healing, both internally and externally, and also that they could play a role against inflammation and may lead to the production of better medicines to be used as supplements in cancer treatment. OBJECTIVES: The acid hydrolysis was studied with H2SO4 at 80% concentration to determine the most effective procedure for total hydrolysis of beta-glucan. The standard of beta-glucans acid hydrolysate were compared for commercial oat and oatmeal, mushrooms: Pleurotus ostreatus, Fungus and yeast Saccharomyces cerevisiae. MATERIAL AND METHODS: The following materials and reagents were used in the examination: reference beta-(1 --> 3)-(1 --> 6)-glucan, oat and oatmeal, mushrooms: Pleurotus ostreatus, Fungus and yeast Saccharomyces cerevisiae. The Raman spectra of the sample solutions (beta-glucan acid hydrolysates) were recorded on a MAGNA-IR 860 with FT-Raman accessory. Sample was irradiated with a 1064 nm line of the T10-8S Nd spectra-physics model: YAG laser and scattered radiation were collected at 180 degrees, using 4 cm(-1) resolution. The polysaccharide was hydrolyzed into component monosaccharides with 80% H2SO4 at 0 degrees C for 30 minutes and monosaccharide derivatives were subjected to electrophoresis, as in a ealier authors study, on a strip of cellulose acetate membrane (CA-SYS-MINI Cellulose Acetate Systems) in 0.2 M Ca(OAc)2 (pH 7.5) at 10 mA, max. 240 V for 1.5 h. The strips were stained with 0.5% toluidine blue in 3% HOAc solution and then rinsed in distilled water and air-dried. RESULTS AND CONCLUSIONS: A part of the hexoses (for example glucose) are converted, to products such as 5-hydroxymethylfurfural. Various coloured substances, through the Maillard reaction have been reported for saccharides. The resulting mono- and oligosaccharides were analysed by cellulose acetate membrane electrophoresis CAE and Raman spectroscopy. Individual bands or CAE spots were selected to monitor the sugar content in medical plant cell walls and to confirm the identity of the analysed sample: oat and oatmeal, mushrooms: Pleurotus ostreatus, Fungus and yeast Saccharomyces cerevisiae. The possibility of a taxonomic classification of products rich in cell-wall materials based on cellulose acetate membrane electrophoresis CAE and Raman spectroscopy for authentication and detection of adulteration of products are discussed.


Assuntos
Materiais Biocompatíveis/análise , Eletroforese em Acetato de Celulose , Análise Espectral Raman , beta-Glucanas/análise , Agaricales/química , Avena/química , Materiais Biocompatíveis/química , Hidrólise , Pleurotus/química , Saccharomyces cerevisiae/química , beta-Glucanas/química
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