arXiv subjects

Herculano da Silva Martinho

Publications and source records attributed to Herculano da Silva Martinho.

4 recordsLinked to original sources

arXiv2014

Low-level laser irradiation-induced changes in bovine spermatozoa

Some biochemical and metabolic characteristics of bovine sperm cells irradiated with low-level laser were probed and correlated to the irradiation parameters. Bovine spermatozoa were exposed to spatially filtered light from a He-Ne laser (633 nm) with fluences from 150 to 600 mJ/cm2. General biochemical alterations were assessed by vibrational spectroscopy (micro-Fourier-Transform Infrared technique). The mitochondrial membrane potential was assessed by flow cytometry. Lipid peroxidation due to reactive oxygen species (ROS) production was assessed by thiobarbituric acid reactive substances (TBARS) assay. Sperm morphologic characteristics changes were probed by atomic force microscopy (AFM) technique. LLLI was able to induce, at different fluences, changes in lipid, DNA and protein contents. Moreover, LLLI also induced changes in TBARS production, suggesting an irradiation effect on lipid peroxidation. Acrosomal reaction induction evidences was found based on changes in protein structure (Amides I and II bands) and AFM characterization. The most interesting result, however, was the changes in methyl and DNA groups, which strongly suggests that LLLI can modify DNA methylation patterns, important for pregnancy establishment. The observed changes in the above-cited parameters have direct impact on sperm quality. The low-level laser irradiation has the potential to improve the fertilizing capacity of bovine sperm cells.

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arXiv2009

Spectral region optimization for Raman-based optical diagnosis of inflammatory lesions

FT-Raman Spectroscopy was applied to identify biochemical alterations existing between inflammatory fibrous hyperplasia (IFH) and normal tissues of buccal mucosa. One important implication of this study is related to the cancer lesion border. In fact, the cancerous normal border line is characterized by the presence of inflammation and its correct discrimination would increase the accuracy in delimiting the lesion frontier. Seventy spectra of IFH from 14 patients were compared to 30 spectra of normal tissue from 6 patients. The statistical analysis was performed with Principal Components Analysis and Soft Independent Modeling Class Analogy methodologies. After studying several spectral ranges it was concluded that the best discrimination capability (sensibility of 95% and specificity of 100%) was found using the 530 to 580 cm$^{-1}$ wavenumbers. The bands in this region are related to vibrational modes of Collagen aminoacids Cistine, Cysteine, and Proline and their relevant contribution to the classification probably relies on the extracellular matrix degeneration process occurring in the inflammatory tissues.

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arXiv2006

Diagnosis of rotator cuff lesions by FT-Raman spectroscopy: a biochemical study

The biochemical changes on normal and degenerated tissues of rotator cuff supraspinatus tendons were probed by FT-Raman spectroscopy. The Raman spectra showed differences on the spectral regions of cysteine, amino acids, nucleic acids, carbohydrates, and lipids. These spectral differences were assigned to pathological biochemical alterations due to the degenerative process of the tendon. Principal Components Analysis was performed on the spectral data and enabled the correct classification of the spectra as normal (grade 1) and degenerated (grades 2 and 3). These findings indicate that Raman spectroscopy could be a very promising tool for the rotator cuff supraspinatus tendon diagnosis and for quantification of their degenerative degree.

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arXiv2006

Biochemical analysis of human breast tissues using FT-Raman spectroscopy

In this work we employ the Fourier Transform Raman Spectroscopy to study normal and tumoral human breast tissues, including several subtypes of cancers. We analyzed 194 Raman spectra from breast tissues that were separated into 9 groups according to their corresponding histopathological diagnosis. The assignment of the relevant Raman bands enabled us to connect the several kinds of breast tissues (normal and pathological) to their corresponding biochemical moieties alterations and distinguish among 7 groups: normal breast, fibrocystic condition, duct carcinoma-in-situ, duct carcinoma-in-situ with necrosis, infiltrating duct carcinoma not otherwise specified, colloid infiltrating duct carcinoma and invasive lobular carcinomas. We were able to establish the biochemical basis for each spectrum, relating the observed peaks to specific biomolecules that play special role in the carcinogenesis process. This work is very useful for the premature optical diagnosis of a broad range of breast pathologies. We noticed that we were not able to differentiate inflammatory and medullary duct carcinomas from infiltrating duct carcinoma not otherwise specified.

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