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.

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.

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.

Nanostructured transdermal hormone replacement therapy for relieving menopausal symptoms: a confocal Raman spectroscopy study

OBJECTIVE: To determine the safety and efficacy of a transdermal nanostructured formulation of progesterone (10%) combined with estriol (0.1%) + estradiol (0.25%) for relieving postmenopausal symptoms. METHODS: A total of 66 postmenopausal Brazilian women with climacteric symptoms of natural menopause received transdermal nanostructured formulations of progesterone and estrogens in the forearm daily for 60 months to mimic the normal ovarian secretory pattern. Confocal Raman spectroscopy of hormones in skin layers was performed. Clinical parameters, serum concentrations of estradiol and follicle-stimulating hormone, blood pressure, BI-RADS classification from bilateral mammography, and symptomatic relief were compared between baseline and 60 months post-treatment. Clinicaltrials.gov: NCT02033512. RESULTS: An improvement in climacteric symptoms was reported in 92.5% of women evaluated before and after 60 months of treatment. The serum concentrations of estradiol and follicle-stimulating hormone changed significantly (p<0.05) after treatment; the values of serum follicle-stimulating hormone decreased after 60 months from 82.04±4.9 to 57.12±4.1 IU/mL. A bilateral mammography assessment of the breasts revealed normal results in all women. No adverse health-related events were attributed to this hormone replacement therapy protocol. CONCLUSION: The nanostructured formulation is safe and effective in re-establishing optimal serum levels of estradiol and follicle-stimulating hormone and relieving the symptoms of menopause. This transdermal hormone replacement therapy may alleviate climacteric symptoms in postmenopausal women. .