Multimodal evaluation of ultra-short laser pulses treatment for skin burn injuries.

Thousands of people die every year from burn injuries. The aim of this study is to evaluate the feasibility of high intensity femtosecond lasers as an auxiliary treatment of skin burns. We used an in vivo animal model and monitored the healing process using 4 different imaging modalities: histology, Optical Coherence Tomography (OCT), Second Harmonic Generation (SHG), and Fourier Transform Infrared (FTIR) spectroscopy. 3 dorsal areas of 20 anesthetized Wistar rats were burned by water vapor exposure and subsequently treated either by classical surgical debridement, by laser ablation, or left without treatment. Skin burn tissues were non-invasively characterized by OCT images and biopsied for further histopathology analysis, SHG imaging and FTIR spectroscopy at 3, 5, 7 and 14 days after burn. The laser protocol was found as efficient as the classical treatment for promoting the healing process. The study concludes to the validation of femtosecond ultra-short pulses laser treatment for skinburns, with the advantage of minimizing operatory trauma.

Analytical quantification of low-density lipoprotein using europium tetracycline indicator.

Low-density lipoprotein (LDL) is known as 'bad' cholesterol. If too much LDL circulates in the blood it can be retained in the walls of the arteries, causing atherosclerosis. In this paper we showed an alternative method to quantify LDL using the europium tetracycline (EuTc) indicator. The optical properties of the EuTc complex were investigated in aqueous solutions containing LDL. An enhancement was observed of the europium luminescence in the solutions with LDL compared those without the lipoprotein. A method to quantify the amount of LDL in a sample, based on EuTc enhanced luminescence, is proposed. The enhancement mechanism is also discussed.

Hair fiber characteristics and methods to evaluate hair physical and mechanical properties / Características da fibra do cabelo e métodos para avaliar o cabelo propriedades físicas e mecânicas

The hair thread is a natural fiber formed by keratin, a protein containing high concentration of sulfur coming from the amino acid cystine. The main physical proprieties of the hair depend mostly on its geometry; the physical and mechanical properties of hair involve characteristics to improve: elasticity, smoothness, volume, shine, and softness due to both the significant adherence of the cuticle scales and the movement control (malleability), as well as the easiness of combing, since they reduce the fibers static electricity. The evaluation of these effects on hair may be carried out by several methods, as: optical and electron microscopy, mechanical resistance measuring, shine evaluation and optical coherence tomography (OCT).

O cabelo é uma fibra natural formada por queratina, uma proteína composta por teor elevado de enxofre proveniente da cistina. As propriedades principais do cabelo dependem de sua geometria, estrutura física. Características físicas e mecânicas das fibras capilares envolvem propriedades que melhoram: elasticidade, maciez, volume, maleabilidade, facilidade para o ato de pentear e brilho. A avaliação de tais propriedades do cabelo pode ser obtida por métodos diversos, como: microscopia óptica e eletrônica, mensuração da resistência mecânica, determinação do brilho e tomografia por coerência óptica (OCT).

Enhancement of europium luminescence in tetracycline-europium complexes in the presence of urea hydrogen peroxide.

An increase in the europium emission band was observed, for the first time, with addition of urea hydrogen peroxide to the tetracycline-europium (Tc-Eu)solution. We have observed that the wavelength, the band width and the area of 5D0-->7F2 europium transition change with the urea hydrogen peroxide concentration. We claim that the tetracycline-europium complexes can be used as probes of urea hydrogen peroxide concentration.