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1.
J Photochem Photobiol B ; 153: 51-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26398811

RESUMO

A new approach to the study of the effects on human skin of mycosporine-like amino acids (MAAs) and gadusol (Gad) incorporated in polymer gel is proposed in this work. The depth profile and photoprotector effects of Pluronic F127® gels containing each of the natural actives were evaluated by in vivo confocal Raman spectroscopy aiming at the analysis of the biochemical changes on human skin. Hierarchical cluster analysis (HCA) showed that the data corresponding to different depths of the skin, from surface to 4 µm, and from 6 to 16 µm, remained in the same cluster. In vivo Raman spectra, classified into five different layers of epidermis according to their similarities, indicated that the amount of Gad gel increased by about 26% in the outermost layer of the stratum corneum (SC) and that MAAs gel at 2 µm depth was 103.4% higher than in the outermost layer of the SC. Variations in the SC of urocanic acid at 1490-1515 cm(-1) and 1652 cm(-1) and histidine at 1318 cm(-1) were calculated, before and after UV exposure with or without gels. With the application of gels the vibrational modes that correspond to lipids in trans conformation (1063 and 1128 cm(-1)) increased with respect to normal skin, whereas gauche conformation (1085 cm(-1)) disappeared. Our studies suggest that gels protected the skin against the stress of the natural defense mechanism caused by high levels of UV exposure.


Assuntos
Pele/efeitos da radiação , Raios Ultravioleta , Administração Tópica , Adulto , Aminoácidos/química , Aminoácidos/farmacologia , Análise por Conglomerados , Cicloexanóis/química , Cicloexanóis/farmacologia , Composição de Medicamentos , Feminino , Géis/química , Humanos , Microscopia Confocal , Poloxâmero/química , Análise de Componente Principal , Pele/efeitos dos fármacos , Pele/patologia , Análise Espectral Raman , Adulto Jovem
2.
Rev. argent. radiol ; 78(4): 223-226, dic. 2014. ilus
Artigo em Espanhol | BINACIS | ID: bin-131239

RESUMO

Si bien la mayoría de los lipomas intestinales son asintomáticos y se diagnostican de manera casual, en algunas ocasiones pueden tener síntomas, como sangrado, diarrea o, con menor frecuencia, obstrucción o invaginación intestinal. Esta última en el adulto es una patología poco común y por lo general tiene una presentación subaguda crónica, cuyo diagnóstico es complicado. La principal técnica de imagen para el diagnóstico de la invaginación intestinal en adultos es la tomografía computada (TC). Solamente un 20% de las invaginaciones son colo-cólicas y en su mayoría son secundarias a un carcinoma. No obstante, en algunas pocas oportunidades pueden ser secundarias a una causa benigna, siendo el lipoma la más usual.(AU)


Even though most of the intestinal lipomas are asymptomatic and are diagnosed by chance, sometimes may have symptoms such as bleeding or diarrhea, and less frequently obstruction or intussusception. Intussusception in adults is a rare condition, and usually has a chronic-subacute presentation, and diagnosis is difficult. CT is the main radiological imaging test for diagnosis. Only 20% of the colonic invaginations are colo-colic, and in most cases are secondary to carcinoma. Rarely are secondary to a benign cause, being the intussusception secondary to a lipoma the most frecuent.(AU)

3.
Rev. argent. radiol ; 78(4): 223-226, dic. 2014. ilus
Artigo em Espanhol | LILACS | ID: lil-734612

RESUMO

Si bien la mayoría de los lipomas intestinales son asintomáticos y se diagnostican de manera casual, en algunas ocasiones pueden tener síntomas, como sangrado, diarrea o, con menor frecuencia, obstrucción o invaginación intestinal. Esta última en el adulto es una patología poco común y por lo general tiene una presentación subaguda crónica, cuyo diagnóstico es complicado. La principal técnica de imagen para el diagnóstico de la invaginación intestinal en adultos es la tomografía computada (TC). Solamente un 20% de las invaginaciones son colo-cólicas y en su mayoría son secundarias a un carcinoma. No obstante, en algunas pocas oportunidades pueden ser secundarias a una causa benigna, siendo el lipoma la más usual.


Even though most of the intestinal lipomas are asymptomatic and are diagnosed by chance, sometimes may have symptoms such as bleeding or diarrhea, and less frequently obstruction or intussusception. Intussusception in adults is a rare condition, and usually has a chronic-subacute presentation, and diagnosis is difficult. CT is the main radiological imaging test for diagnosis. Only 20% of the colonic invaginations are colo-colic, and in most cases are secondary to carcinoma. Rarely are secondary to a benign cause, being the intussusception secondary to a lipoma the most frecuent.


Assuntos
Humanos , Masculino , Intussuscepção , Lipoma , Vômito , Tomografia , Ultrassonografia , Gastrectomia , Náusea
4.
Lasers Med Sci ; 29(4): 1429-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24573956

RESUMO

The aim of this study was to find the apoptosis molecular markers involved in the cell death that might be related to photodynamic therapy (PDT) mechanisms in breast cancer. The mammary tumors were induced in 25 Sprague-Dawley female rats by a single, oral gavage of 7,12-dimethylbenz(a)anthracene (DMBA; 70 mg/kg body weight). Animals were divided into four groups: G1 (normal, without DMBA), G2 (control, without PDT treatment), G3 (euthanized 48 h after PDT), and G4 (euthanized 24 h after PDT). For PDT experiments, the photosensitizer used was Photodithazine, and 100 J/cm of light at a fluence rate of 100 mW/cm was delivered to treat lesions. A sample of each animal was investigated by quantitative real-time PCR using Rat Apoptosis RT2 Profiler™ PCR Array platform. The results showed 20 genes with differential expression between PDT and control groups. A significant upregulation was observed for pro-apoptotic genes CASP4, CASP12, CIDEA, GADD45A, and FAS and downregulation of anti-apoptotic genes MAPK8IP1, TNFRSF11B, and NAIP2 in PDT-treated tumors. These results indicate that these genes are more directly involved in cell apoptosis induced by PDT.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/genética , Glucosamina/análogos & derivados , Neoplasias Mamárias Experimentais/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Feminino , Expressão Gênica , Glucosamina/farmacologia , Glucosamina/uso terapêutico , Lasers Semicondutores , Neoplasias Mamárias Experimentais/induzido quimicamente , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
5.
Artigo em Inglês | MEDLINE | ID: mdl-23792287

RESUMO

Surface enhancement Raman scattering (SERS) of two tautomer of thiobarbituric acid was obtained using silver and gold nanoparticles. Large band enhancement in the region of the ν(C=S), ν(C=C), δ(CH2), and δ(CNH) vibrational modes was found. Natural bond analysis of the tautomer species revealed expressive values of charge transfer, principally from lone pair electron orbitals of the S, N, and O atoms. Complete vibrational assignment was done for the two tautomers using the B3LYP/6-311+G (d, p) procedure, band deconvolution analysis, and from a rigorous interpretation of the normal modes matrix. The calculated spectra agree well with the experimental ones.


Assuntos
Tiobarbitúricos/química , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Estereoisomerismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-23588299

RESUMO

Surface-enhanced Raman scattering (SERS) was used to study the interactions of the normal modes of the bis(diethyldithiocarbamate)zinc(II) complex, [Zn(DDTC)2], on nano-structured silver surfaces. The electronic spectrum of this complex was measured and the charge transfer bands were assigned through the TD-PBE1PBE procedure. To see the electronic dispersion, the Mulliken electronic charges were calculated for each normal mode and correlated with the SERS effect. Full assignment of the SERS spectra was also supported by carefully analysis of the distorted geometries generated by the normal modes.


Assuntos
Complexos de Coordenação/química , Ditiocarb/química , Zinco/química , Elétrons , Modelos Moleculares , Espectrofotometria Ultravioleta , Análise Espectral Raman
7.
Artigo em Inglês | MEDLINE | ID: mdl-23376262

RESUMO

In this study, we evaluated models that can be used to simulate amino acids in biological environments via density functional theory (DFT). The goal was to obtain realistic representations that combine computational economy and result quality when compared to experimental data. We increased the complexity of the models by using a model of an amino acid in a vacuum, followed by a water-solvated amino acid model. To consider pH variation, we simulated zwitterionic and nonionic amino acid configurations. The amino acid chosen for testing was phenylalanine, an aromatic amino acid present in high concentrations in the natural moisturizing factor of skin that plays a fundamental role in ultraviolet protection and vitiligo disease. To validate the models, vibrational modes and electronic properties were calculated and compared to experimental results.


Assuntos
Fenilalanina/química , Modelos Moleculares , Teoria Quântica , Análise Espectral Raman , Água/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-23314390

RESUMO

Theoretical and experimental bands have been assigned for the Fourier Transform Infrared (FT-IR) and Fourier Transform Raman (FT-Raman) spectra of the bis-(diethydithiocarbamate)Zn(II) complex, [Zn(DDTC)(2)]. The calculations and spectra interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra as well as band deconvolution analysis. To assign the metal-ligand normal modes the deviation percentage of the geometrical parameters was used. Results confirms a pseudo tetrahedral structure around the Zn(II) cation. The calculated infrared and Raman spectra has an excellent agreement with the experimental spectra. The Natural Bond Orbital analysis (NBO) was carried out as a way to study the Zn(II) hybridization leading to the pseudo tetrahedral geometry of the framework of the [Zn(DDTC)(2)] complex, and to study also which are the donor NBO and the acceptor NBO in meaningful charge transfer through the Second Order Perturbation Theory Analysis of Fox Matrix in NBO basis.


Assuntos
Complexos de Coordenação/química , Ditiocarb/química , Zinco/química , Modelos Moleculares , Teoria Quântica , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 105: 259-66, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23314391

RESUMO

Theoretical and experimental bands have been assigned for the Fourier Transform Infrared (FT-IR) and FT-Raman spectra of the bis(diethydithiocarbamate)Cu(II) complex, [Cu(DDTC)(2)]. The calculations and spectra interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra, and band deconvolution analysis. To better assign the metal-ligand normal modes in the spectral region of low energy, the deviation percentage of the geometrical parameters was used, with values from the interpretation of the normal modes of L matrix. Results indicate a planar structure around the Cu(II) cation. The calculated infrared and Raman spectra, based on the proposed geometrical structure of the bis(diethyldithiocarbamate)copper(II) complex, agreed with the experimental spectra.


Assuntos
Complexos de Coordenação/química , Cobre/química , Ditiocarb/química , Complexos de Coordenação/síntese química , Ditiocarb/síntese química , Modelos Moleculares , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
10.
Artigo em Inglês | MEDLINE | ID: mdl-22925980

RESUMO

The aspartateguanidoacetatenickel (II) complex, [Ni(Asp)(GAA)], was synthesized and structural analysis was performed by means of the experimental methods: determination of the C, H, N and O contents, thermogravimetry, infrared and Raman spectroscopy. DFT:B3LYP/6-311G(d, p) calculations have been performed giving optimized structure and harmonic vibrational wavenumbers. Second derivative of the FT-infrared, FT-Raman and Surface Raman Enhanced Scattering (SERS) spectra, and band deconvolution analysis were also performed. Features of the FT-infrared, FT-Raman and SERS confirmed theoretical structure prediction. Full assignment of the vibrational spectrum was also supported by a carefully analysis of the distorted geometries generated by the normal modes. The Natural Bond Orbital analysis (NBO) was also carried out as a way to study the Ni (II) hybridization leading to the pseudo planar geometry of the framework, and the extension of the atomic N and O hybrid orbital of the different amino acids in the bond formation. Bands of charge transfer and d-d transitions were assigned in the UV-Vis spectrum.


Assuntos
Ácido Aspártico/química , Elétrons , Modelos Moleculares , Níquel/química , Compostos Organometálicos/química , Teoria Quântica , Análise Espectral Raman , Vibração , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
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