Analysis of Human Tooth Pulp Chamber Temperature After 670 nm Laser Irradiation: In Vitro Study.

Objective: One of the limiting factors of employing laser radiation on dental therapies is the potential of causing thermal injuries to pulp tissues. The purpose of this study was to evaluate intra-chamber temperature increase on extracted human teeth exposed to 670 nm wavelength InGaAlP laser diode radiation.

Materials And Methods: In vitro intra-chamber temperature measurements of 12 standardized human teeth (incisors, canines, premolars, and molars; n = 3) were taken both before and after laser radiation.

Paraconsistent analysis network applied in the treatment of Raman spectroscopy data to support medical diagnosis of skin cancer.

Paraconsistent logic (PL) is a type of non-classical logic that accepts contradiction as a fundamental concept and has produced valuable results in the analysis of uncertainties. In this work, algorithms based on a type of PL-paraconsistent annotated logic of two values (PAL2v)-are interconnected into a network of paraconsistent analysis (PANnet). PANnet was applied to a dataset comprising 146 Raman spectra of skin tissue biopsy fragments of which 30 spectra were determined to represent normal skin tissue (N), 96 were determined to represent tissue with basal cell carcinoma, and 19 were determined to be tissue with melanoma (MEL).

Discrimination of non-melanoma skin lesions from non-tumor human skin tissues in vivo using Raman spectroscopy and multivariate statistics.

Background And Objective: Raman spectroscopy was used to discriminate human non-melanoma skin lesions from non-tumor tissues in vivo. This work proposed the discrimination between non-melanoma (basal cell carcinoma, BCC; squamous cell carcinoma, SCC) and pre-cancerous lesions (actinic keratosis, AK) from benign lesions and normal (non-tumor group, NT) tissues, using near-infrared Raman spectroscopy with a Raman probe.

Materials And Methods: Prior to surgery, the spectra of suspicious lesions were obtained in situ.

Identification of different forms of cocaine and substances used in adulteration using near-infrared Raman spectroscopy and infrared absorption spectroscopy.

Identification of cocaine and subsequent quantification immediately after seizure are problems for the police in developing countries such as Brazil. This work proposes a comparison between the Raman and FT-IR techniques as methods to identify cocaine, the adulterants used to increase volume, and possible degradation products in samples seized by the police. Near-infrared Raman spectra (785 nm excitation, 10 sec exposure time) and FT-IR-ATR spectra were obtained from different samples of street cocaine and some substances commonly used as adulterants.

Could the bone mineral density (T-score) be correlated with the Raman spectral features of keratin from women's nails and be used to predict osteoporosis?

Osteoporosis is a disease with great importance in current public health due to the associated risk of fracture; therefore, a rapid and accurate diagnosis becomes increasingly important. Recent literature has described a possible relationship between the changes in the organic phase of bone and the changes in nail keratin measured through Raman spectroscopy, aiming at the development of a standard for measuring bone quality and fracture risk both rapid and accurately. This work evaluated the correlation between the bone mineral density (BMD) scores of women with and without osteoporotic disease with the changes in the Raman spectra of the nail keratin, by assessing the intensity of the peak at 510 cm(-1) (S-S bridge) and the scores of principal component analysis (PCA), correlated with the values of BMD measured at the lumbar and hip.

Discrimination of prostate carcinoma from benign prostate tissue fragments in vitro by estimating the gross biochemical alterations through Raman spectroscopy.

Raman spectroscopy has been proposed for detecting biochemical alterations in prostate cancer (PrCa) compared to benign prostate tissue in in vitro fragments from surgery for diagnostic purposes. Freezer-stored fragments of human prostate tissues were unfrozen and submitted to Raman spectroscopy with a dispersive spectrometer (830-nm and 200-mW laser parameters, 30-s exposure time). Fragments were fixed and submitted to histopathology to grade PrCa according to Gleason score.

Discriminating neoplastic and normal brain tissues in vitro through Raman spectroscopy: a principal components analysis classification model.

Background And Objective: Because of their aggressiveness, brain tumors can lead to death within a short time after diagnosis. Optical techniques such as Raman spectroscopy may be a technique of choice for in situ tumor diagnosis, with potential use in determining tumor margins during surgery because of its ability to identify biochemical changes between normal and tumor brain tissues quickly and without tissue destruction.

Methods: In this work, fragments of brain tumor (glioblastoma, medulloblastoma, and meningioma) and normal tissues (cerebellum and meninges) were obtained from excisional intracranial surgery and from autopsies, respectively.

Discriminating model for diagnosis of basal cell carcinoma and melanoma in vitro based on the Raman spectra of selected biochemicals.

Raman spectroscopy has been employed to identify differences in the biochemical constitution of malignant [basal cell carcinoma (BCC) and melanoma (MEL)] cells compared to normal skin tissues, with the goal of skin cancer diagnosis. We collected Raman spectra from compounds such as proteins, lipids, and nucleic acids, which are expected to be represented in human skin spectra, and developed a linear least-squares fitting model to estimate the contributions of these compounds to the tissue spectra. We used a set of 145 spectra from biopsy fragments of normal (30 spectra), BCC (96 spectra), and MEL (19 spectra) skin tissues, collected using a near-infrared Raman spectrometer (830 nm, 50 to 200 mW, and 20 s exposure time) coupled to a Raman probe.

Discrimination of basal cell carcinoma and melanoma from normal skin biopsies in vitro through Raman spectroscopy and principal component analysis.

Objective: Raman spectroscopy has been employed to discriminate between malignant (basal cell carcinoma [BCC] and melanoma [MEL]) and normal (N) skin tissues in vitro, aimed at developing a method for cancer diagnosis.

Background Data: Raman spectroscopy is an analytical tool that could be used to diagnose skin cancer rapidly and noninvasively.

Methods: Skin biopsy fragments of ≈ 2 mm(2) from excisional surgeries were scanned through a Raman spectrometer (830 nm excitation wavelength, 50 to 200 mW of power, and 20 sec exposure time) coupled to a fiber optic Raman probe.

Differential diagnosis between experimental endophthalmitis and uveitis in vitreous with Raman spectroscopy and principal components analysis.

Raman spectroscopy has been used for the diagnosis of various eye diseases. A diagnostic tool based on Raman spectroscopy has been developed to discriminate endophthalmitis from uveitis in vitreous tissues of rabbits' eyes in vitro. Twenty-two New Zealand rabbits suffering from endophthalmitis induced by Staphylococcus aureus (n=10), non-infectious uveitis induced by lipopolysaccharide from Escherichia coli (LPS) (n=10 animals) and control (n=2) were included in the study.

Classification model based on Raman spectra of selected morphological and biochemical tissue constituents for identification of atherosclerosis in human coronary arteries.

This study presents the results of Raman spectroscopy applied to the classification of arterial tissue based on a simplified model using basal morphological and biochemical information extracted from the Raman spectra of arteries. The Raman spectrograph uses an 830-nm diode laser, imaging spectrograph, and a CCD camera. A total of 111 Raman spectra from arterial fragments were used to develop the model, and those spectra were compared to the spectra of collagen, fat cells, smooth muscle cells, calcification, and cholesterol in a linear fit model.

Effects of different swimming exercise intensities on bone tissue composition in mice: a Raman spectroscopy study.

Objective: Raman spectroscopy was employed to evaluate the effect of different swimming intensities on femoral bone composition in an animal model.

Background Data: Intense swimming exercise may affect bone mineralization, and Raman technique has been shown to be effective in evaluating tissue composition (phosphate minerals and carbonate apatites - bands at 960 and 1170 cm(-1), as well as collagen matrix - amide I band at 1660 cm(-1)).

Materials And Methods: Eighteen female Swiss Webster mice were separated into three groups (n = 6 per group) of sedentary (SED), and swimming with an intensity of 40% (PT-40) and 80% (PT-80) of the maximum load, with 6 weeks of training.

Raman spectroscopy validation of DIAGNOdent-assisted fluorescence readings on tibial fractures treated with laser phototherapy, BMPs, guided bone regeneration, and miniplates.

Objectives: We aimed to assess through Raman spectroscopy and fluorescence the levels of calcium hydroxyapatite (CHA) and lipids and proteins in complete fractures treated with internal rigid fixation (IRF) treated or not with laser phototherapy (LPT) and associated or not with bone morphogenetic proteins (BMPs) and guided bone regeneration (GBR).

Background: Fractures have different etiologies and treatments and may be associated with bone losses. LPT has been shown to improve bone healing.

Effects of laser photherapy on bone defects grafted with mineral trioxide aggregate, bone morphogenetic proteins, and guided bone regeneration: a Raman spectroscopic study.

We have used Raman analysis to assess bone healing on different models. Benefits on the isolated or combined use of mineral trioxide aggregate, bone morphogenetic proteins, guided bone regeneration and laser on bone repair have been reported, but not their combination. We studied peaks of hydroxyapatite and CH groups on defects grafted with MTA, treated or not with laser, BMPs, and GBR.

Near-infrared Raman spectroscopy to detect anti-Toxoplasma gondii antibody in blood sera of domestic cats: quantitative analysis based on partial least-squares multivariate statistics.

Toxoplasmosis is an important zoonosis in public health because domestic cats are the main agents responsible for the transmission of this disease in Brazil. We investigate a method for diagnosing toxoplasmosis based on Raman spectroscopy. Dispersive near-infrared Raman spectra are used to quantify anti-Toxoplasma gondii (IgG) antibodies in blood sera from domestic cats.

The effect of the association of near infrared laser therapy, bone morphogenetic proteins, and guided bone regeneration on tibial fractures treated with internal rigid fixation: a Raman spectroscopic study.

Fractures have different etiology and treatment and may be associated or not to bone losses. Laser light has been shown to improve bone healing. We aimed to assess, through Raman spectroscopy, the level of CHA (approximately 958 cm(-1)) on complete fractures animals treated with IRF treated or not with Low Level Laser Therapy-LLLT and associated or not to BMPs and GBR.

Differentiating normal and basal cell carcinoma human skin tissues in vitro using dispersive Raman spectroscopy: a comparison between principal components analysis and simplified biochemical models.

Objective: Raman spectroscopy has been used to detect spectral differences between normal and basocellular cell carcinoma (BCC) skin tissues that are related to biochemical alterations between tissues.

Background Data: Raman spectroscopy is an analytic tool that could detect biochemical alterations in tissues, and its use would lead to real-time and less-invasive cancer diagnosis.

Methods: Raman spectra from human tissue fragments (normal and BCC) were obtained in a dispersive, near-infrared Raman spectrometer (laser parameters: 830 nm, 80 mW) with a CCD detector.

Exercise order interacts with rest interval during upper-body resistance exercise.

The purpose of this study was to compare repetition performance when resting 1 minute vs. 3 minutes between sets and exercises for an upper-body workout performed in 2 different sequences. Sixteen recreationally trained men completed 4 experimental resistance exercise sessions.

Force, reaction time, and precision of Kung Fu strikes.

The goal was to compare values of force, precision, and reaction time of several martial arts punches and palm strikes performed by advanced and intermediate Kung Fu practitioners, both men and women. 13 Kung Fu practitioners, 10 men and three women, participated. Only the men, three advanced and seven intermediate, were considered for comparisons between levels.

Use of 660-nm diode laser in the prevention and treatment of human oral mucositis induced by radiotherapy and chemotherapy.

Objective: The aim of this multidisciplinary study was to evaluate quantitatively and qualitatively the effect of a 660-nm diode laser in the prevention and treatment of human oral mucositis (OM) in patients suffering from head and neck cancer who had undergone radiotherapy and chemotherapy.

Background Data: OM is a severe oral lesion resulting from the toxic effects of treatment for cancer in the head and neck region. Low-level laser therapy is indicated to prevent and treat this oral complication and may be used alone or in association with conventional drug treatment, producing pain relief and wound repair.

ProRaman: a program to classify Raman spectra.

The program ProRaman, developed for the Matlab platform, provides an interactive and flexible graphic interface to develop efficient algorithms to classify Raman spectra into two or three different classes. A set of preprocessing algorithms to decrease the variable dimensionality and to extract the main features which improve the correct classification ratio was implemented. The implemented classification algorithms were based on the Mahalanobis distance and neural network.

Cytotoxicity of octal-bromide zinc phthalocyanine after photodynamic therapy with different light sources.

Objective: The objective of this study was to investigate the cytotoxicity of octal-bromide zinc phthalocyanine (ZnPcBr8) at different concentrations (0.25, 0.5, and 1 microM) after irradiating HEp-2 cell cultures with two different light sources: a diode semiconductor laser (660 nm, 30 mW) or an LED (640 nm, 70 mW).

The effects of low-level light emitting diode on the repair process of Achilles tendon therapy in rats.

Thirty Wistar rats (350 +/- 20 g) were subjected to total Achilles tendon tenotomy of the right fore limb. They were submitted to a daily dose of 20 J/cm(2) light emitting diode (LED) (640 +/- 20 nm) therapy. The LED was applied punctually and transcutaneously to the lesioned region.

Catheters: instrumental advancements in biomedical applications of optical fibers.

This review is focused on the advancements in biomedical engineering regarding the elaboration of new prototypes of optical fiber catheters to be applied in spectroscopic analysis, such as Raman and fluorescence spectroscopy. Our group has contributed to the development of new prototypes with interesting properties, such as side-viewing signal excitation and collection, distal tip with bending control, and Raman scattering minimization from the optical fiber. In addition, several groups have contributed to other new catheter-improving properties of this spectroscopic device.