Monografias, Dissertações e Teses
URI permanente desta comunidadehttps://repositorioacademico.universidadebrasil.edu.br/handle/123456789/1
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Item Aplicação in vivo não invasiva da espectroscopia Raman confocal na identificação de alterações relacionadas à idade no estrato córneo e epiderme humana(Universidade Brasil, 2024) Abdala, Julia Marinzeck de Alcantara; Martin, Airton Abrahão; Fávero, Priscila PereiraHuman skin comprises layers known as the stratum corneum and the epidermis, each possessing biomolecules, structure and functions. The Raman spectroscopy technique enables research on the biochemical composition of biological samples in vivo, such as skin, its biomolecules and biomarkers, in a selective and non-destructive way, allowing for in vivo examination of tissue layers. This elucidates the biophysical links between vibrational characteristics and changes in specific chemical compositions. This study aims to use confocal Raman spectroscopy to evaluate age related biochemical and spectral changes in the stratum corneum and human epidermis, focusing specifically on spectral modifications in the natural moisturizing factor (NMF), keratin, lipids and proteins. Skin-related data were acquired using a confocal Raman system with a 785 nm diode laser, which consisted of two defined age groups, group I, 27±3 years, and group II, 55±4 years, comprising 71 volunteers. Multivariate statistical analyses were used to interpret and classify the average spectral data from each skin layer. Analyses measured two different skin groups and revealed the most representative peaks for the stratum corneum and epidermis. Amide III and amide I, both in the α-helical conformation, showed increased signals in the spectra of the epidermis and stratum corneum of group I. It was observed that increased keratin filament cross-linking with age is a possible contributor to the increase in stiffness, which consequently led to a decrease in the Raman signal in group II. The opposite occurred with the lipid signal, as changes in the lateral packaging of lipids indicated skin aging with an increase in the Raman signal in group II. The difference between the NMF means was statistically significant between the two age groups. Thus, the present research fills an important current research gap in differentiating skin characteristics across different age groups and their layers using confocal Raman spectroscopy.Item Estudo dos efeitos bioquímicos da luz azul na pele humana por Espectroscopia Raman Confocal(Universidade Brasil, 2021) Bello, Larissa Karoline Zago Rogoni; Fávero, Priscila Pereira; Martin, Airton AbrahãoIntroduction: Raman spectroscopy is a recent and non-invasive technique that can be used to assess a biochemical structure of the skin under different conditions. This technique is already useful in several contexts, although additional studies are still being published. The effect of blue light on the skin and its clinical functions, such as photoaging, have been described in the literature. In addition, the light component of solar radiation is shown to be a risk factor for several diseases, such as melanoma, such as skin patches, pigmented nevi and other skin lesions. Thus, an investigation of the effects of blue light using Raman spectroscopy is useful and necessary for the current scenario. Objective: To understand biochemical changes in human skin due to the incidence of blue light, using Raman Conforcal Spectroscopy. Method: This is a monocentric, retrospective study, based on the analysis of a database with prospective collection carried out in accordance with DermoProbes' operational procedure. Results: After irradiation of the blue LED for 15 minutes (100 J / cm2), damage was observed in the stratum corneum, which corresponds to disulfide, tyrosine, phenylanine and beta-carotene bonds, and damage to Amide I in the viable epidermis. After subsequent irradiation, in the same area, for another 15 minutes (totaling 200 J / cm2), an increase in the damage to the viable epidermis was observed. For this irradiation the signatures in the bands of felilalanine, L-glutamano, valine, lipoic acid and beta-carotene stand out. When compared to irradiated skin with virgin skin for 45 minutes (corresponding to 3 incidences of 15 minutes, totaling 300 J / cm2), it was observed that the separation by cluster of virgin and irradiated skin is complete, for this irradiation, it stands out as signatures of oleic acid and Amide III. It was found that different doses act on different molecular groups of the stratum corneum and dermis. When the damage is intense as proteins are the most affected and when the damage is less, the antioxidant beta carotene and amino acids such as tyrosine and phenylalanine are activated. Conclusion: The present study, from the analysis of Raman spectroscopy, as the main biochemical changes in the skin after different intensities of blue light irradiation. From the results obtained, it was possible to verify that the damage to the biochemistry of the skin increases as the exposure to blue light increases, at a wavelength similar to the visible component of sunlight.Item Caracterização e padronização bioquímica de bactérias (ATCC) de interesse clínico para dermatite atópica: espectrocospia Raman(Universidade Brasil, 2020) Oliveira, Rogério Philippov de; Martin, Airton Abrahão; Téllez-Soto, Cláudio Alberto; Khouri, SoniaThe present work deals with the analysis and characterization of the most important microorganisms related to intact skin and in patients affected by atopic dermatitis (AD). During the course of this research, it was proposed to observe the behavior and mechanisms of action of colonizing microorganisms involved in skin tissue damaged by AD and the consequent loss of philagrin with changes in the skin barrier. The analyzes were performed by collection with a disposable loop directly from the colonies in the cultures in Petri dishes. Four microorganisms were analyzed by Raman spectroscopy, namely ATCC (American Type Culture Collection) strains of Staphylococcus aureus-25923, Staphylococcus epidermidis-12228, Streptococcus pyogenes-19615 and Pseudomonas aeruginosa 10145. Through 2nd derivatives, the Raman spectra showed different characteristics in relation to the protein and lipid content among the four bacteria analyzed. Statistical methods such as spectral mean and standard deviation, PCA (Principal Component Analysis) and Ward's Dendogram were also applied, in which all showed low dispersion and discrepancy in their data. The methodology employed can show the efficacy of Raman spectroscopy applied to biological samples as a tool for determining the skin barriers integrity and presenting paths for the future development of new drugs, lotions or ointments in helping the treatment of patients affected by atopic dermatitis resulting from microbial biofilms.