Topical dexpanthenol effects on physiological parameters of the stratum corneum by Confocal Raman Microspectroscopy.

BACKGROUND: Topical use of dexpanthenol presents well-established moisturizing properties and maintenance and repair of the skin barrier function, however, its exact action mechanisms are not completely elucidated. In this context, Confocal Raman Microspectroscopy is an optical method that enables non-invasive and non-destructive in vivo analysis with the sensitive acquisition of molecular changes in different skin layers. Herein, the aim was to evaluate the effects of topical dexpanthenol on the components and physiological parameters of the stratum corneum (SC). MATERIALS AND METHODS: Ten healthy female subjects underwent skin evaluation by means of a Confocal Raman Spectrometer Skin Analyzer 3510. Spectral data were obtained from the skin of the anterior forearm region, before and 2 h after applying a cosmetic formulation containing or not containing 5% dexpanthenol. RESULTS: Semiquantitative analysis of the natural moisturizing factor showed a significant decrease in content after 2 h of topical dexpanthenol application, while the analysis of the lamellar organization of intercellular lipids and the secondary structure of keratin showed a significant increase in hexagonal organization of lipids at the first half of the SC and a significant increase in ß-pleated sheet conformation of keratin. CONCLUSION: Effects of topical dexpanthenol on SC suggest a contribution in increasing fluidity of both lipidic and protein components of the SC and are compatible with dexpanthenol activity in maintaining adequate physiological conditions and preventing transepidermal water loss. This study also contributes to the elucidation of action mechanisms and other concurrent biochemical processes.

Identification of biomarkers in diabetic nails by Raman spectroscopy.

BACKGROUND: The growth of Diabetes Mellitus (DM) is a serious public health issue which is more prevalent in developing countries. The main problems related to DM are the gradual changes in the structural and functional integrity of tissues caused by hyperglycemia, which calls for early diagnosis and periodic monitoring exams. Recent studies suggest that the quality of the nail plate has great potential to assess the secondary complications of DM. Hence, this study aimed to determine the biochemical characteristics of the nails of individuals with DM2 by Raman confocal spectroscopy (CRS). METHODS: We collected fragments from the distal region of the fingernails of 30 healthy volunteers and 30 volunteers with DM2. The samples were analyzed by CRS (Xplora - Horiba) coupled to a 785 nm laser. RESULTS: Alterations in different biochemical components, such as proteins, lipids, amino acids, and final agents of advanced glycation, and alterations in the disulfide bridges, which are important in stabilizing keratin in nails were identified. CONCLUSION: The spectral signatures and new DM2 markers in nails were identified. Therefore, the possibility of acquiring biochemical information by evaluating the nails of diabetics, a simple and easily acquired material associated with the CRS technique, may allow health complications to be detected quickly.

Correlation between ankle-brachial index and thermography measurements in patients with peripheral arterial disease.

OBJECTIVES: To correlate the ankle-brachial index and photographic thermography findings in patients with peripheral arterial disease. METHODS: Photographic thermography was performed at the foot level, and ankle-brachial index was measured in 72 lower limbs of 53 patients with peripheral arterial disease who were divided into calcified artery, patients with an ankle-brachial index greater than 1.4; and non-calcified artery classified as asymptomatic, mild, moderate, and severe on the basis of peripheral arterial disease severity. Fisher's exact test was used for categorical data, and Wilcoxon test was used for numerical data. RESULTS: Spearman's correlation analysis showed a strong correlation (R = 0.7) between the ankle-brachial index and the mean plantar temperature in patients without lower limb artery calcification. Linear regression yielded the predictor equation Y = 3.296 × X + 29.75, wherein ankle-brachial index (X) can be predicted on the basis of temperature values. Spearman's correlation test showed no significance (p = 0.2174) in patients with arterial calcification. Kruskal-Wallis test with post hoc analysis using Dunn's test for multiple comparisons showed that the mean plantar temperature was lower in patients with arterial calcification. CONCLUSION: Photographic thermography findings show a strong correlation with ankle-brachial index in patients with non-calcified arteries.

Short-term and long-term effects of osteoporosis on incisor teeth and femoral bones evaluated by Raman spectroscopy and energy dispersive X-ray analysis in ovariectomized rats.

There are few published data on the relationship between loss of bone mass due to osteoporosis and poor tooth quality. This study analyzed the effects of osteoporosis on incisor teeth and femoral bones using optical techniques in rats. Twenty female Wistar rats aged 6 months (n = 20) were randomized into two groups: control group, non-ovariectomized rats (n = 10); ovariectomy group, ovariectomized rats to induce osteoporosis (n = 10). Each group was subdivided randomly into two groups containing five rats each as follows. Control group 1: non-ovariectomized rats euthanized at the age of 9 or 3 months post-ovariectomy (n = 5); Control group 2: non-ovariectomized rats euthanized at the age of 1 year or 6 months post-ovariectomy (n = 5); ovariectomy group 1: ovariectomized rats euthanized at the age of 9 months or 3 months post-ovariectomy (n = 5); ovariectomy group 2: ovariectomized rats euthanized at the age of 1 year or 6 months post-ovariectomy (n = 5). The incisor teeth and femoral bones of Wistar rats were removed to perform Raman spectroscopy using an excitation laser at 785 nm. In addition, an energy-dispersive X-ray spectrometer system was used to evaluate calcium (Ca) and phosphorus (P). The main findings included significant changes (p < 0.05) for phosphate and carbonate band areas for both incisor teeth and femur bones. In addition, there was significant negative correlation between the P concentration and phosphate/carbonate ratio (lower P content-larger ratio, p < 0.05) for incisor teeth and femoral bones. The proline and CH2 wag band areas were significantly reduced only for the incisor teeth (p < 0.05). Therefore, Raman spectroscopy assessed the compositional, physicochemical and structural changes in hard tissue. The current study also pointed out the possible action mechanisms of these changes, bone fracture risk and dental fragility. It is important to emphasize that poor dental quality may also occur due to osteoporosis.

In vitro effects of alcohol-containing mouthwashes on human enamel and restorative materials.

The objective of this study was to evaluate the in vitro effects, including surface morphological characteristics and chemical elemental properties, of different mouthwash formulations on enamel and dental restorative materials, simulating up to 6 months of daily use. Human enamel samples, hydroxyapatite, composite resin, and ceramic surfaces were exposed to 3 different mouthwashes according to label directions - Listerine® Cool Mint®, Listerine® Total Care, and Listerine® Whitening - versus control (hydroalcohol solution) to simulate daily use for up to 6 months. The samples were analyzed using scanning electron microscopy (SEM), infrared spectrophotometry (µ-Fourier transform infrared microscopy), energy-dispersive X-ray (EDX) spectroscopy, and color analysis before and after exposure. No relevant changes were observed in the morphological characteristics of the surfaces using SEM techniques. The physical and chemical aspects of the enamel surfaces were evaluated using mid-infrared spectroscopy, and EDX fluorescence was used to evaluate the elemental aspects of each surface. There was no variation in the relative concentrations of calcium and phosphorus in enamel, silicon and barium in composite resin, and silicon and aluminum in the ceramic material before and after treatment. No relevant changes were detected in the biochemical and color properties of any specimen, except with Listerine® Whitening mouthwash, which demonstrated a whitening effect on enamel surfaces. Long-term exposure to low pH, alcohol-containing, and peroxide-containing mouthwash formulations caused no ultra-structural or chemical elemental changes in human enamel or dental restorative materials in vitro.

In vivo study of dermal collagen of striae distensae by confocal Raman spectroscopy.

This research work mainly deals with studying qualitatively the changes in the dermal collagen of two forms of striae distensae (SD) namely striae rubrae (SR) and striae albae (SA) when compared to normal skin (NS) using confocal Raman spectroscopy. The methodology includes an in vivo human skin study for the comparison of confocal Raman spectra of dermis region of SR, SA, and NS by supervised multivariate analysis using partial least squares discriminant analysis (PLS-DA) to determine qualitatively the changes in dermal collagen. These groups are further analyzed for the extent of hydration of dermal collagen by studying the changes in the water content bound to it. PLS-DA score plot showed good separation of the confocal Raman spectra of dermis region into SR, SA, and NS data groups. Further analysis using loading plot and S-plot indicated the participation of various components of dermal collagen in the separation of these groups. Bound water content analysis showed that the extent of hydration of collagen is more in SD when compared to NS. Based on the results obtained, this study confirms the active involvement of dermal collagen in the formation of SD. It also emphasizes the need to study quantitatively the role of these various biochemical changes in the dermal collagen responsible for the variance between SR, SA, and NS.

In vitro effects of alcohol-containing mouthwashes on human enamel and restorative materials

Abstract The objective of this study was to evaluate the in vitro effects, including surface morphological characteristics and chemical elemental properties, of different mouthwash formulations on enamel and dental restorative materials, simulating up to 6 months of daily use. Human enamel samples, hydroxyapatite, composite resin, and ceramic surfaces were exposed to 3 different mouthwashes according to label directions — Listerine® Cool Mint®, Listerine® Total Care, and Listerine® Whitening — versus control (hydroalcohol solution) to simulate daily use for up to 6 months. The samples were analyzed using scanning electron microscopy (SEM), infrared spectrophotometry (µ-Fourier transform infrared microscopy), energy-dispersive X-ray (EDX) spectroscopy, and color analysis before and after exposure. No relevant changes were observed in the morphological characteristics of the surfaces using SEM techniques. The physical and chemical aspects of the enamel surfaces were evaluated using mid-infrared spectroscopy, and EDX fluorescence was used to evaluate the elemental aspects of each surface. There was no variation in the relative concentrations of calcium and phosphorus in enamel, silicon and barium in composite resin, and silicon and aluminum in the ceramic material before and after treatment. No relevant changes were detected in the biochemical and color properties of any specimen, except with Listerine® Whitening mouthwash, which demonstrated a whitening effect on enamel surfaces. Long-term exposure to low pH, alcohol-containing, and peroxide-containing mouthwash formulations caused no ultra-structural or chemical elemental changes in human enamel or dental restorative materials in vitro.

Molecular and morphological surface analysis: effect of filling pastes and cleaning agents on root dentin.

OBJECTIVE: This study evaluated the effect of different filling pastes and cleaning agents on the root dentin of primary teeth using Fourier-transformed Raman spectroscopy (FT-Raman), micro energy-dispersive X-ray fluorescence (µ-EDXRF) and scanning electron microscopic (SEM) analysis. MATERIAL AND METHODS: Eighty roots of primary teeth were endodontically prepared and distributed into 4 groups and filled according to the following filling pastes: Control-no filling (CP), Calen®+zinc oxide (CZ), Calcipex II® (CII), Vitapex® (V). After seven days, filling paste groups were distributed to 4 subgroups according to cleaning agents (n=5): Control-no cleaning (C), Ethanol (E), Tergenform® (T), 35% Phosphoric acid (PA). Then, the roots were sectioned and the dentin root sections were internally evaluated by FT-Raman, µ-EDXRF and SEM. Data was submitted to two-way ANOVA and Tukey tests (α=0.05). RESULTS: Regarding filling pastes, there was no significant difference in organic content. CP provided the lowest calcium values and, calcium/phosphoric ratio (Ca/P), and the highest phosphoric values. For cleaning agents there was no difference in organic content when compared to the C; however, T showed significantly higher calcium and Ca/P than PA. All groups showed similar results for phosphorus. The dentin smear layer was present after use of the cleaning agents, except PA. CONCLUSION: The filling pastes changed the inorganic content, however they did not change the organic content. Cleaning agents did not alter the inorganic and organic content. PA cleaned and opened dentin tubules.

Molecular and morphological surface analysis: effect of filling pastes and cleaning agents on root dentin

Abstract The quality of the dentin root is the most important factor for restoration resin sealing and drives the outcome of endodontic treatment. Objective This study evaluated the effect of different filling pastes and cleaning agents on the root dentin of primary teeth using Fourier-transformed Raman spectroscopy (FT-Raman), micro energy-dispersive X-ray fluorescence (µ-EDXRF) and scanning electron microscopic (SEM) analysis. Material and Methods Eighty roots of primary teeth were endodontically prepared and distributed into 4 groups and filled according to the following filling pastes: Control-no filling (CP), Calen®+zinc oxide (CZ), Calcipex II® (CII), Vitapex® (V). After seven days, filling paste groups were distributed to 4 subgroups according to cleaning agents (n=5): Control-no cleaning (C), Ethanol (E), Tergenform® (T), 35% Phosphoric acid (PA). Then, the roots were sectioned and the dentin root sections were internally evaluated by FT-Raman, µ-EDXRF and SEM. Data was submitted to two-way ANOVA and Tukey tests (α=0.05). Results Regarding filling pastes, there was no significant difference in organic content. CP provided the lowest calcium values and, calcium/phosphoric ratio (Ca/P), and the highest phosphoric values. For cleaning agents there was no difference in organic content when compared to the C; however, T showed significantly higher calcium and Ca/P than PA. All groups showed similar results for phosphorus. The dentin smear layer was present after use of the cleaning agents, except PA. Conclusion The filling pastes changed the inorganic content, however they did not change the organic content. Cleaning agents did not alter the inorganic and organic content. PA cleaned and opened dentin tubules.

Estudo de linfonodos por espectroscopia Raman confocal / Lymph node study by confocal Raman spectroscopy

Dentre os órgãos linfoides encontram-se os linfonodos. Também conhecidos como nódulos linfáticos, os quais são considerados como filtros da linfa por serem ricos em linfócitos e outras células de defesa. Entre os fatores que contribuem para o seu comprometimento temos a invasão de sua estrutura por células neoplásicas. A citologia constitui o exame padrão ouro no diagnóstico sendo, a PAAF a técnica mais utilizada para a obtenção do material a ser analisado. Entretanto, alguns estudos questionam a sua utilização, devido à perda da arquitetura celular. A espectroscopia Raman confocal por meio da sua capacidade em utilizar as diferenças bioquímicas de tecidos e células vem se destacando cada vez mais neste tipo de diagnóstico. O estudo teve por objetivo identificar as principais características bioquímicas em linfonodos normais, comprometidos e lesão cervical utilizando a espectroscopia Raman confocal. Foram analisadas 12 amostras de linfonodos normais e alterados de pacientes com indicação cirúrgica para linfadenectomia pela espectroscopia seguida pela análise estatística de componentes principais (PCA) e análise de discriminante linear (LDA). Após as análises observou-se que a técnica utilizada conseguiu discriminar os tecidos com valores de especificidade, sensibilidade e acurácia de 83%. Portanto, a espectroscopia Raman confocal se mostrou uma importante ferramenta na caracterização de linfonodos podendo futuramente auxiliar no diagnóstico de lesões linfonodais.

Among the lymphoid organs there are lymph nodes,, which are considered as lymph filters because they are rich in lymphocytes and other defense cells. Among the factors that contribute to their impairment we note the invasion of its structure by neoplastic cells. Cytology is the gold-standard diagnostic test, and FNA is the technique most used to obtain the material to be analyzed. However, some studies question its use, due to the loss of cellular architecture. Confocal Raman spectroscopy, through its ability to utilize biochemical differences in tissues and cells, has been increasingly prominent in this type of diagnosis. The study aimed to identify the main biochemical characteristics in normal and compromised lymph nodes and cervical lesion using confocal Raman spectroscopy. We analyzed 12 normal and altered lymph node samples from patients with medical indications for a lymphadenectomy by spectroscopy, followed by statistical analysis of the main components (PCA) and linear discriminant analysis (LDA). After the analysis, it was observed that this technique was able to discriminate the tissues with values of specificity, sensitivity and accuracy of up to 83%. Therefore, confocal Raman spectroscopy has been shown to be an important tool in the characterization of lymph nodes, and may help in the diagnosis of lymph node lesions in the future.

Analysis of molecular markers as predictive factors of lymph node involvement in breast carcinoma.

Nodal status is the most significant independent prognostic factor in breast cancer. Identification of molecular markers would allow stratification of patients who require surgical assessment of lymph nodes from the large numbers of patients for whom this surgical procedure is unnecessary, thus leading to a more accurate prognosis. However, up to now, the reported studies are preliminary and controversial, and although hundreds of markers have been assessed, few of them have been used in clinical practice for treatment or prognosis in breast cancer. The purpose of the present study was to determine whether protein phosphatase Mg2+/Mn2+ dependent 1D, ß-1,3-N-acetylglucosaminyltransferase, neural precursor cell expressed, developmentally down-regulated 9, prohibitin, phosphoinositide-3-kinase regulatory subunit 5 (PIK3R5), phosphatidylinositol-5-phosphate 4-kinase type IIα, TRF1-interacting ankyrin-related ADP-ribose polymerase 2, BCL2 associated agonist of cell death, G2 and S-phase expressed 1 and PAX interacting protein 1 genes, described as prognostic markers in breast cancer in a previous microarray study, are also predictors of lymph node involvement in breast carcinoma Reverse transcription-quantitative polymerase chain reaction analysis was performed on primary breast tumor tissues from women with negative lymph node involvement (n=27) compared with primary tumor tissues from women with positive lymph node involvement (n=23), and was also performed on primary tumors and paired lymph node metastases (n=11). For all genes analyzed, only the PIK3R5 gene exhibited differential expression in samples of primary tumors with positive lymph node involvement compared with primary tumors with negative lymph node involvement (P=0.0347). These results demonstrate that the PIK3R5 gene may be considered predictive of lymph node involvement in breast carcinoma. Although the other genes evaluated in the present study have been previously characterized to be involved with the development of distant metastases, they did not have predictive potential.

Micro-Raman spectroscopic study of thyroid tissues.

Thyroid carcinomas are the most common endocrine malignancy. Inconclusive results for the analysis of malignancies are an issue in the diagnosis of thyroid carcinomas; 20% of thyroid cancer diagnoses are indeterminate or suspicious, resulting in a surgical procedure without immediate need. The use of Raman spectroscopy may help improve the diagnosis of thyroid carcinoma. In this study, 30 thyroid samples, including normal thyroid, goiter and thyroid cancer, were analyzed by confocal Raman spectroscopy. Principal component analysis (PCA), linear discriminant analysis (LDA) with cross validation and binary logistic regression (BLR) analysis were applied to discriminate among tissues. Significant discrimination was observed, with a consistent rate of concordant pairs of 89.2% for normal thyroid versus cancer, 85.7% for goiter versus cancer and 80.6% for normal thyroid versus goiter using just the amide III region. Raman spectroscopy was thus proven to be an important and fast tool for the diagnosis of thyroid tissues. The spectral region of 1200-1400cm-1 discriminated normal versus goiter tissues despite the great similarity of these tissues.

In vivo Confocal Raman Spectroscopic Analysis of the Effects of Infrared Radiation in the Human Skin Dermis.

Human skin is the outer covering of the body, and its composition changes with overexposure to environmental pollution and solar radiation. Infrared (IR) radiation is capable of penetrating more deeply into the skin producing free radicals causing irreversible damage. Confocal Raman spectroscopy was considered as a potential tool for the in vivo analysis of the different metabolic conditions with respect to different depths of the skin. In this regard, this work verifies the influence of infrared radiation on the skin dermis after having been exposed to 432 J cm-2 which corresponds to the dose received in a day in the summer time in a tropical region. This study was performed with 17 female volunteers who were divided into two groups. The marked skin area was exposed twice to IR radiation for a duration of 30 min each with an interval of 30 min. The spectral signatures were collected in the fingerprint region before (T0) and after 60 min (T60) of IR irradiation. The analysis shows that, on average, no significant variations occurred in group I and decreased collagen was observed in group II. However, when considering the effect seen in each individual, collagen degradation was detected in 60% of volunteers.

DFT:B3LYP/3-21G theoretical insights on the confocal Raman experimental observations in skin dermis of healthy young, healthy elderly, and diabetic elderly women.

In the confocal Raman spectra of skin dermis, the band area in the spectral region of proline and hydroxyproline varies according to the age and health condition of the volunteers, classified as healthy young women, healthy elderly women, and diabetic elderly women. Another observation refers to the intensity variation and negative Raman shift of the amide I band. To understand these effects, we adopted a model system using the DFT/B3LYP:3-21G procedure, considering the amino acid chain formed by glycine, hydroxyproline, proline, and alanine, which interacts with two and six water molecules. Through these systems, polarizability variations were analyzed to correlate its values with the observed Raman intensities of the three groups of volunteers and to assign the vibrational spectra of the skin dermis. As a way to correlate other experimental trends, we propose a model of chemical reaction of water interchange between the bonding amino acids, in which water molecules are attached with glucose by hydrogen bonds. The theoretical results are in accordance with the observed experimental trends.

Effects of Bleaching Agents Combined with Regular and Whitening Toothpastes on Surface Roughness and Mineral Content of Enamel.

OBJECTIVE: The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes. BACKGROUND DATA: Bleaching treatment could promote morphological and chemical changes in enamel surface. METHODS: Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%). RESULTS: Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content. CONCLUSIONS: The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.

Biochemical imaging of normal, adenoma, and colorectal adenocarcinoma tissues by Fourier transform infrared spectroscopy (FTIR) and morphological correlation by histopathological analysis: preliminary results

Introduction The colorectal cancer is a major health problem worldwide. Histology is considered the gold standard for differential diagnosis. However, it depends on the observer's experience, which can lead to discrepancies and poor results. Spectroscopic imaging by Fourier transform infrared (FTIR) is a technique that may be able to improve the diagnosis, because it is based on biochemical differences of the structural constituents of tissue. Therefore, the main goal of this study was to explore the use of FTIR imaging technique in normal colon tissue, colorectal adenoma, and adenocarcinoma in order to correlate their morphological structures with their biochemical imaging. Methods Samples were collected from normal (n = 4), adenoma (n = 4), and adenocarcinoma human colorectal tissue (n = 4) from patients undergoing colonoscopy or surgical resection of colon lesions. The samples were sectioned with a cryostat in sequential sections; the first slice was placed on CaF2 slide and the second slice was placed on glass slide for histological analysis (HE staining). The cluster analyses were performed by the software Cytospec (1.4.02)®. Results In normal samples, biochemical analysis classified six different structures, namely the lamina propria of mucous glands (epithelial cells and goblet cells), central lumen of the gland, mucin, and conjunctive tissue. In samples with adenoma and adenocarcinoma, altered regions could also be identified with high sensitivity and specificity. Conclusion The results of this study demonstrate the potential and viability of using infrared spectroscopy to identify and classify colorectal tissues.

In vitro effects of hydrogen peroxide combined with different activators for the in-office bleaching technique on enamel.

OBJECTIVE: The aim of this study was to evaluate the alteration of human enamel bleached with high concentrations of hydrogen peroxide associated with different activators. MATERIALS AND METHODS: Fifty enamel/dentin blocks (4 × 4 mm) were obtained from human third molars and randomized divided according to the bleaching procedure (n = 10): G1 = 35% hydrogen peroxide (HP - Whiteness HP Maxx); G2 = HP + Halogen lamp (HL); G3 = HP + 7% sodium bicarbonate (SB); G4 = HP + 20% sodium hydroxide (SH); and G5 = 38% hydrogen peroxide (OXB - Opalescence Xtra Boost). The bleaching treatments were performed in three sessions with a 7-day interval between them. The enamel content, before (baseline) and after bleaching, was determined using an FT-Raman spectrometer and was based on the concentration of phosphate, carbonate, and organic matrix. Statistical analysis was performed using two-way ANOVA for repeated measures and Tukey's test. RESULTS: The results showed no significant differences between time of analysis (p = 0.5175) for most treatments and peak areas analyzed; and among bleaching treatments (p = 0.4184). The comparisons during and after bleaching revealed a significant difference in the HP group for the peak areas of carbonate and organic matrix, and for the organic matrix in OXB and HP+SH groups. Tukey's analysis determined that the difference, peak areas, and the interaction among treatment, time and peak was statistically significant (p < 0.05). CONCLUSION: The association of activators with hydrogen peroxide was effective in the alteration of enamel, mainly with regards to the organic matrix.

Evaluation of inorganic and organic bone components after application of an apatite-coated Al2O3 implants as scaffolds for bone repair

The aim of this work was to study the influence of uncoated and apatite-coated Al2O3 implants on bone regeneration after 30 days of surgery in New Zealand white rabbits. Twelve samples of Al2O3 implants were prepared and half of them (n = 6) were apatite-coated by the modified biomimetic method. Three experimental groups were tested as Group C - control, surgery procedure without cerami c implant, Group Ce - uncoated Al 2O3 implants (n = 6) and Group CeHA - apatite-coated Al2O3 implants (n = 6). The mineralization of the Al2O3 implants was analyzed in bone fragments using FT-Raman spectroscopy. Raman peaks at 959 cm-1 and 2940 cm-1 evaluated the inorganic and organic bone content, respectively. In vivo citotoxicity was analyzed using micronucleus test. Inorganic and organic content were higher in CeHA samples than in Ce and C (CeHA > Ce > C). FT-Raman spectroscopy showed that the higher the deposition of the organic matrix, more mineralization occurred. The micronucleus test showed that the uncoated and apatite-coated Al2O3 implants were non-cytotoxic and safe to in vivo applications.

Confocal Raman spectroscopy: determination of natural moisturizing factor profile related to skin hydration

INTRODUCTION: Skin health and skin care to reduce the effects of aging are the main interests of many researchers. The skin is very important because it protects the body from various effects of the external environment, and studies of the largest organ of the human body have been conducted since antiquity. In skin, aging effects are severe enough to promote changes in cell structure and biochemical composition. In this study, we quantitatively analyzed the water content and natural moisturizing factor of human facial skin in vivo and in real time by confocal Raman spectroscopy. This non-invasive technique is capable of providing detailed information on the biochemical composition at different depth profiles in the skin. METHODS: We studied 10 volunteers, phototype II (40 and 50 years old), using a confocal Raman system to examine the skin surface down to 25 µm. Raman spectra were obtained before product use (T0), and after 30 days of continuous use of cosmetics (T30). RESULTS: The results show a significant increase of 6.4% in water content in the surface layer of the facial skin after the cosmetic use. The amounts of natural moisturizing factor (NMF) compounds were also increased. Urocanic acid underwent a greater change in relation to carboxylic acid pyrrolidone, with a 38.5% increase in the stratum corneum. CONCLUSION: Confocal Raman spectroscopy identified changes in the biochemical composition of the superficial layers of the epidermis, which suggests the anti-aging efficacy of the formulation.

FT-Raman spectroscopic study of skin wound healing in diabetic rats treated with Cenostigma macrophyllum Tul

INTRODUCTION: Patients with diabetes mellitus exhibit a delay in the lesion repair process. The active components of Cenostigma macrophyllum may represent a viable alternative to facilitate the recovery of these lesions. The aim of this study was to evaluate the effects of emulsion oil-water Cenostigma macrophyllum in the repair process of lesions in rats with induced diabetes. METHODS: 63 male rats (Wistar, 200-250 g body weight, 30-40 days old) were distributed into the following groups: control (C), diabetic (D) and diabetic treated with Cenostigma macrophyllum (P), subdivided based on the experimental times, days 7, 14 and 28, with 21 animals per main group. Diabetes mellitus (DM) was induced by administration of streptozotocin (50 mg/kg via penile vein and 12-h fasting) and confirmed at day 21 (glycemic index > 240 mg/dL). In the animals of group P, 0.5 ml of the oil-water emulsion obtained from the plant seed was used. The samples were removed and hemisectioned, and one portion was used for the quantitative histological analysis of collagen using Masson's trichrome staining, while another portion was analyzed by FT-Raman spectroscopy. RESULTS: A higher percentage area of the volume of collagen fibers was observed for the experimental time Day 14 in group P compared with group D (p < 0.001). Regarding the ratio of areas of the amides I (1700‑1600 cm-1) and III (1245-1345 cm-1), the groups D and P show the opposite behavior. CONCLUSION: Cenostigma macrophyllum accelerated the repair process in skin of diabetic ratsfor14 days.