Imaging cervical cytology with scanning near-field optical microscopy (SNOM) coupled with an IR-FEL

Cervical cancer remains a major cause of morbidity and mortality among women, especially in the developing world. Increased synthesis of proteins, lipids and nucleic acids is a pre-condition for the rapid proliferation of cancer cells. We show that scanning near-field optical microscopy, in combination with an infrared free electron laser (SNOM-IR-FEL), is able to distinguish between normal and squamous low-grade and high-grade dyskaryosis, and between normal and mixed squamous/glandular pre-invasive and adenocarcinoma cervical lesions, at designated wavelengths associated with DNA, Amide I/II and lipids. These findings evidence the promise of the SNOM-IR-FEL technique in obtaining chemical information relevant to the detection of cervical cell abnormalities and cancer diagnosis at spatial resolutions below the diffraction limit (?0.2 \ensuremathμm). We compare these results with analyses following attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy; although this latter approach has been demonstrated to detect underlying cervical atypia missed by conventional cytology, it is limited by a spatial resolution of ~3 \ensuremathμm to 30 \ensuremathμm due to the optical diffraction limit

Mass spectrometry and multivariate analysis to classify cervical intraepithelial neoplasia from blood plasma: an untargeted lipidomic study

Cervical cancer is still an important issue of public health since it is the fourth most frequent type of cancer in women worldwide. Much effort has been dedicated to combating this cancer, in particular by the early detection of cervical pre-cancerous lesions. For this purpose, this paper reports the use of mass spectrometry coupled with multivariate analysis as an untargeted lipidomic approach to classifying 76 blood plasma samples into negative for intraepithelial lesion or malignancy (NILM, n = 42) and squamous intraepithelial lesion (SIL, n = 34). The crude lipid extract was directly analyzed with mass spectrometry for untargeted lipidomics, followed by multivariate analysis based on the principal component analysis (PCA) and genetic algorithm (GA) with support vector machines (SVM), linear (LDA) and quadratic (QDA) discriminant analysis. PCA-SVM models outperformed LDA and QDA results, achieving sensitivity and specificity values of 80.0% and 83.3%, respectively. Five types of lipids contributing to the distinction between NILM and SIL classes were identified, including prostaglandins, phospholipids, and sphingolipids for the former condition and Tetranor-PGFM and hydroperoxide lipid for the latter. These findings highlight the potentiality of using mass spectrometry associated with chemometrics to discriminate between healthy women and those suffering from cervical pre-cancerous lesions

Tracking the Impact of Excisional Cervical Treatment on the Cervix using Biospectroscopy

Local excisional treatment for cervical intra-epithelial neoplasia (CIN) is linked to significant adverse sequelae including preterm birth, with cone depth and radicality of treatment correlating to the frequency and severity of adverse events. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy can detect underlying cervical disease more accurately than conventional cytology. The chemical profile of cells pre- and post-treatment may differ as a result of altered biochemical processes due to excision, or treatment of the disease. Since pre-treatment cervical length varies amongst women, the percentage of cervix excised may correlate more accurately to risk than absolute dimensions. We show that treatment for CIN significantly alters the biochemistry of the cervix, compared with women who have not had treatment; this is due to the removal of cervical tissue rather than the removal of the disease. However, the spectra do not seem to correlate to the cone depth or proportion of cervical length excised. Future research should aim to explore the impact of treatment in a larger cohort

Determinantes individuales y sociales del estado de salud subjetivo y bienestar de la población de la tercera edad de Portugal

This article aims to identify the main determinants of self-rated health and well-being in the elderly Portuguese population, using a set of dimensions including demographic and socioeconomic indicators, characteristics of interpersonal networks and social activities, health, sexual activity, representations of aging, and feeling of happiness. Taking socioeconomic, behavioral, and attitudinal predictors into account to analyze the explanatory value of the interrelated dimensions and weights for each factor, the author argues that social capital, activities associated with active aging, and greater optimism towards aging can contribute greatly to better self-rated health and wellbeing among the elderly, partially offsetting the effect of socioeconomic factors and illness associated with age.Neste artigo pretende-se identificar os principais determinantes da autoavaliação do estado de saúde e do bem-estar da população sênior, tendo em conta um conjunto de dimensões que reúnem indicadores demográficos e socioeconômicos, características das redes interpessoais e atividades sociais praticadas, de saúde, atividade sexual, de representações sobre o envelhecimento e sentimento de felicidade. A equação em simultâneo de preditores socioeconômicos e de caráter comportamental e atitudinal dessas várias vertentes, com o intuito de analisar o valor explicativo de cada uma das dimensões inter-relacionadas e o peso de cada um dos fatores, permite concluir que o social capital, a prática de atividades associadas ao envelhecimento ativo e um maior otimismo em relação ao envelhecimento podem contribuir em grande medida para uma melhor autoavaliação do estado de saúde e do bemestar dos mais velhos, compensando, em parte, o efeito de fatores socioeconômicos e de doença associados à idade

Simultaneous determination of BTX and total hydrocarbons in water employing near infrared spectroscopy and multivariate calibration

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)A method for the simultaneous determination of benzene, toluene and xylenes (BTX) in water based on the use of a silicone sensing phase, detection by near infrared spectroscopy and multivariate calibration is described. A Doehlert design was employed to define the calibration and external validation sets, which were prepared in the concentration ranges of 2.0-30 mg L(-1) for benzene, 4.0-40 mg L(-1) for toluene and 1.0-15 mg L(-1) for xylenes: these ranges were selected after evaluation of the concentration of these compounds in a water sample contaminated by gasoline. The determinations were performed by inserting a polydimethylsiloxane (PDMS) rod (3.2 mm diameter and 5.0 mm long) into a flask containing the aqueous BTX solution (without headspace), made 3.0 mol L(-1) with sodium chloride in order to improve the extraction of the hydrocarbons by the polymer. After extraction, the cylinder was placed in a home-made cell for absorbance measurements from 800 to 2500 nm. The calibration models were constructed using Partial Least Square (PLS) regression and Multiple Linear Regression (MLR), with variables selected by the Successive Projection Algorithm (SPA). PLS models provided relative errors of prediction of 10.9%, 13.3%, 21.9% and 9.6% for benzene, toluene, xylenes and total hydrocarbons, respectively. These values can be considered acceptable for the concentration range studied, indicating that the proposed method can be useful for simultaneous determination of aromatic compounds in water employing NIR. (C) 2011 Elsevier B.V. All rights reserved.1601691697Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FACEPEFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2008/57808-1]CNPq [573894/2008-6

Improving the detection limits of near infrared spectroscopy in the determination of aromatic hydrocarbons in water employing a silicone sensing phase

This work describes the use of a silicone sensing phase for the detection of aromatic hydrocarbons in water employing near infrared spectroscopy and the exploitation of the salting-out effect as a means of improving the limits of detection of the method. Sensing phases of polydimethylsiloxane (PDMS) were prepared from Silastic T2 (Dow Corning). Determinations were carried out by immersing a disk in a flask containing an aqueous solution of aromatic hydrocarbon (benzene, toluene, ethylbenzene and the xylenes, commonly called BTEX) and left under constant stirring. Afterwards, the disk was removed from the contaminated water, dried and placed in a home-made holder for absorbance measurements from 800 to 2500 nm, employing an MB 160 Bomem spectrophotometer. By employing a 2.0-mm height disk, measurements performed in water provided detection limits (3(sblank)/sensitivity) of 1.1, 1.8, 1.1 and 1.1 mg L-1 for benzene, toluene, ethylbenzene and xylenes, respectively, while LOD values of 0.6, 0.7, 0.6 and 0.7 mg L-1 were obtained when sample solutions contained 2.0 mol L-1 sodium chloride. Detection limits of 0.080, 0.12, 0.14 and 0.27 mg L-1 were obtained with the use of a 5.0-mm height disk and 2.0 mol L-1 sodium chloride. Sodium chloride improves the limits of detection due to its salting out effect; however, headspace in the flask must be avoided during measurements, as the hydrocarbons are preferentially lost to the air. The precision of the proposed method was evaluated by constructing three analytical curves for toluene, providing average slopes and linear coefficients with relative standard deviations of 5.8 and 3.8%, respectively. (c) 2007 Elsevier B.V. All rights reserved.125122923

CLASSIFICATION OF BRAZILIAN COFFEE USING NEAR-INFRARED SPECTROSCOPY AND MULTIVARIATE CALIBRATION

This work describes the use of near infrared spectroscopy (NIRS) and chemometric techniques calibration for the classification of coffee samples from different lots and producers acquired in supermarkets and roasting industries in some Brazilian cities. Seventy-three samples of finely ground roasted coffee were acquired in the market and 91 samples of roasted ground Arabica beans were analyzed in the full NIR spectral range (800-2500 nm) using a diffuse reflectance accessory coupled to an MB160 Bomem spectrophotometer. Two classification models were constructed: Soft Independent Modeling Class Analogy (SIMCA) and PLS Discriminant Analysis (PLS-DA). All findings reveal that NIR spectroscopy, coupled with either SIMCA or PLS-DA multivariate models, can be a useful tool to differentiate roasted coffee grains and to replace sensory tests.45777478

Barcoding without DNA? Species identification using near infrared spectroscopy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Hennig's holomorphology concept defines taxonomy as a process that synthesizes evidence from all relevant comparative sources. One possible source is metabolomics, in which the global metabolic profile is analyzed. An integral metabolic profile can be quickly obtained, nondestructively, through spectroscopy in the near infrared region. Here we use near infrared spectroscopy and chemometry to identify nine species of flies in the genus Neodexiopsis Malloch (Muscidae, Diptera). This genus is the most species-rich of the Muscoidea in the Neotropical region. Identification success demonstrates that near infrared spectroscopy may provide a new source of data to test and organize hypotheses of species delimitation. Comparing near infrared spectroscopy with DNA barcoding, spectroscopy may have even greater conceptual merit as a true barcode of life.29334654Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Active bacterial flora surrounding foraminifera (xenophyophorea) living on the deep-sea floor

Using a scanning near-field optical microscope coupled to an infrared free electron laser (SNOM-IR-FEL) in low-resolution transmission mode, we collected chemical data from whole cervical cells obtained from 5 pre-menopausal, non-pregnant women of reproductive age, and cytologically classified as normal or with different grades of cervical cell dyskaryosis. Imaging data are complemented by demography. All samples were collected before any treatment. Spectra were also collected using attenuated total reflection, Fourier-transform (ATR-FTIR) spectroscopy, to investigate the differences between the two techniques. Results of this pilot study suggests SNOM-IR-FEL may be able to distinguish cervical abnormalities based upon changes in the chemical profiles for each grade of dyskaryosis at designated wavelengths associated with DNA, Amide I/II, and lipids. The novel data sets are the first collected using SNOM-IR-FEL in transmission mode at the ALICE facility (UK), and obtained using whole cells as opposed to tissue sections, thus providing an ‘intact’ chemical profile. These data sets are suited to complementing future work on image analysis, and/or applying the newly developed algorithm to other datasets collected using the SNOM-IR-FEL approach