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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.

We set out to determine whether near infrared reflectance spectroscopy (NIRS) combined with principal component analysis-linear discriminant analysis (LDA) or, variable selection techniques employing successive projection algorithm or genetic algorithm (GA) could evaluate the bone repair in cranial critical-size (5 mm) defect after stimulation with collagen sponge scaffold and/or infrared low-level laser therapy directly on the local. Forty-five Winstar rats were divided into nine groups of five each, namely: group H - healthy, n = 5 (without treatment and without cranial critical-size defect), (GI positive control - n = 5, 21 days or n = 5, 30 days) without treatment and with cranial critical-size defect; (GII-n = 5, 21 days or n = 5, 30 days) cranial critical-size defect filled with collagen sponge scaffold; (GIII-n = 5, 21 days or n = 5, 30 days) cranial critical-size defect submitted to low-level laser therapy; (GIV-n = 5, 21 days or n = 5, 30 days) cranial critical-size defect submitted to combined collagen sponge scaffold + low-level laser therapy treatment. In relation to the histological analysis, the collagen sponge scaffold + low-level laser therapy treatment group (GIV) 30 days showed the best result with the presence of secondary bone, immature bone (osteoid) and newly formed connective tissue (periosteum). GA-LDA model also successfully classified control class of the others classes. Thus, the results provided by the good-quality classification model revealed the feasibility of NIRS for application to evaluation of the wound healing in rat cranial defect, thanks to the short analysis time of a few seconds and nondestructive advantages of NIRS as an alternative approach for bone repair purposes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1160-1168, 2017., (© 2017 American Institute of Chemical Engineers.)

Cyanobacteria are a group of photosynthetic, nitrogen-fixing bacteria present in a wide variety of habitats such as freshwater, marine, and terrestrial ecosystems. In this work, the effects of As(III), a major toxic environmental pollutant, on the lipidomic profiles of two cyanobacteria species (Anabaena and Planktothrix agardhii) were assessed by means of a recently proposed method based on the concept of regions of interest (ROI) in liquid chromatography mass spectroscopy (LC-MS) together with multivariate curve resolution alternating least squares (MCR-ALS). Cyanobacteria were exposed to two concentrations of As(III) for a week, and lipid extracts were analyzed by ultrahigh-performance liquid chromatography/time-of-flight mass spectrometry in full scan mode. The data obtained were compressed by means of the ROI strategy, and the resulting LC-MS data sets were analyzed by the MCR-ALS method. Comparison of profile peak areas resolved by MCR-ALS in control and exposed samples allowed the discrimination of lipids whose concentrations were changed due to As(III) treatment. The tentative identification of these lipids revealed an important reduction of the levels of some galactolipids such as monogalactosyldiacylglycerol, the pigment chlorophyll a and its degradation product, pheophytin a, as well as carotene compounds such as 3-hydroxycarotene and carotene-3,3'-dione, all of these compounds being essential in the photosynthetic process. These results suggested that As(III) induced important changes in the composition of lipids of cyanobacteria, which were able to compromise their energy production processes. Graphical abstract Steps of the proposed LC-MS + MCR-ALS procedure.

The aim of this work was to develop an analytical method to predict total anthocyanins content (TAC) and total phenolic compounds (TPC) in intact wax jambu fruit [Syzygium malaccense (L.) Merryl et Perry] using near-infrared spectroscopy (NIRS) and partial least squares (PLS). The estimation accuracy was based on parameters such as root mean square error of prediction (RMSEP), correlation coefficients [calibration (rc) and prediction (rp) set] and ratio of performance to deviation (RPD). TAC, rp = 0.98, RMSEP = 9.0 mg L(-1) and RPD = 5.19 were attained using second derivative pre-treatment. TPC, rp = 0.94, RMSEP = 22.18 (mg gallic acid equivalents (GAE)/100g) and RPD = 3.27 (excellent accuracy) were also obtained using second derivative pre-treatment. These findings suggest that the NIRS and PLS algorithms can be used to determine TCA and TPC in intact wax jambu fruit., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Klebsiella pneumoniae Carbapenemase (KPC-2)-producing and non-producing Klebsiella pneumoniae (KP) have rapidly disseminated worldwide, challenging the diagnostics of Gram-negative infections. We evaluate the potential of a novel non-destructive and rapid method based on Near-Infrared Spectroscopic (NIRS) and multivariate analysis for distinguishing KPC-2-producing and non-producing KP. Thirty-nine NIRS spectra (24 KPC-2-producing KP, 15 KPC-2 non-producing KP) were acquired; different pre-processing methods such as baseline correction, derivative and Savitzky-Golay smoothing were performed. A spectral region fingerprint was achieved after using genetic algorithm-linear discriminant analysis (GA-LDA) and successive projection algorithm (SPA-LDA) algorithms for variable selection. The variables selected were then used for discriminating the microorganisms.Accuracy test results including sensitivity and specificity were determined. Sensitivity in KPC-2 producing and non-producing KP categories was 66.7% and 75%, respectively, using a SPA-LDA model with 66 wavenumbers. The resulting GA-LDA model successfully classified both microorganisms with respect to their "fingerprints" using only 39 wavelengths. Sensitivity in KPC-2 producing category was moderate(≈66.7%) using a GA-LDA model. However, sensitivity in KPC-2 non-producing category using GA-LDA accurately predicted the correct class (with 100% accuracy). As100% accuracy was achieved, this novel approach identifies potential biochemical markers that may have a relation with microbial functional roles and means of rapid identification of KPC-2 producing and non-producing KP strains., (Copyright © 2014 Elsevier B.V. All rights reserved.)