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1.
Appl Spectrosc ; 78(5): 477-485, 2024 May.
Article in English | MEDLINE | ID: mdl-38373402

ABSTRACT

Core needle biopsy is a part of the histopathological process, which is required for cancerous tissue examination. The most common method to guide the needle inside of the body is ultrasound screening, which in greater part is also the only guidance method. Ultrasound screening requires user experience. Furthermore, patient involuntary movements such as breathing might introduce artifacts and blur the screen. Optically enhanced core needle biopsy probe could potentially aid interventional radiologists during this procedure, providing real-time information on tissue properties close to the needle tip, while it is advancing inside of the body. In this study, we used diffuse optical spectroscopy in a custom-made core needle probe for real-time tissue classification. Our aim was to provide initial characteristics of the smart needle probe in the differentiation of tissues and validate the basic purpose of the probe of informing about breaking into a desired organ. We collected optical spectra from rat blood, fat, heart, kidney, liver, lungs, and muscle tissues. Gathered data were analyzed for feature extraction and evaluation of two machine learning-based classifiers: support vector machine and k-nearest neighbors. Their performances on training data were compared using subject-independent k-fold cross-validation. The best classifier model was chosen and its feasibility for real-time automated tissue recognition and classification was then evaluated. The final model reached nearly 80% of correct real-time classification of rat organs when using the needle probe during real-time classification.


Subject(s)
Support Vector Machine , Animals , Rats , Needles , Liver/pathology , Liver/diagnostic imaging , Kidney/pathology , Kidney/chemistry , Lung/pathology , Lung/diagnostic imaging , Spectrum Analysis/methods , Spectrum Analysis/instrumentation , Biopsy, Large-Core Needle/instrumentation , Biopsy, Large-Core Needle/methods , Male , Machine Learning
2.
Sci Rep ; 13(1): 2370, 2023 02 09.
Article in English | MEDLINE | ID: mdl-36759533

ABSTRACT

The study was aimed to evaluate the performance of a newly developed spectroscopy-based non-invasive and noncontact device (SAMIRA) for the simultaneous measurement of hemoglobin, bilirubin and oxygen saturation as an alternative to the invasive biochemical method of blood sampling. The accuracy of the device was assessed in 4318 neonates having incidences of either anemia, jaundice, or hypoxia. Transcutaneous bilirubin, hemoglobin and blood saturation values were obtained by the newly developed instrument which was corroborated with the biochemical blood tests by expert clinicians. The instrument is trained using Artificial Neural Network Analysis to increase the acceptability of the data. The artificial intelligence incorporated within the instrument determines the disease condition of the neonate. The Pearson's correlation coefficient, r was found to be 0.987 for hemoglobin estimation and 0.988 for bilirubin and blood gas saturation respectively. The bias and the limits of agreement for the measurement of all the three parameters were within the clinically acceptance limit.


Subject(s)
Bilirubin , Hemoglobins , Oxygen Saturation , Oxygen , Point-of-Care Systems , Spectrum Analysis , Humans , Infant, Newborn , Artificial Intelligence , Bilirubin/blood , Hemoglobins/analysis , Oxygen/blood , Spectrum Analysis/instrumentation , Spectrum Analysis/methods , Optical Imaging/instrumentation , Optical Imaging/methods
3.
Braz. J. Pharm. Sci. (Online) ; 59: e22111, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439497

ABSTRACT

Abstract Chagas disease is a neglected parasitic disease caused by Trypanosoma cruzi, whose treatment has remained unsatisfactory for over 50 years, given that it is limited to two drugs. Benznidazole (BZN) is an efficient antichagasic drug used as the first choice, although its poor water-solubility, irregular oral absorption, low efficacy in the chronic phase, and various associated adverse effects are limiting factors for treatment. Incorporating drugs with such characteristics into nanostructured lipid carriers (NLC) is a promising alternative to overcome these limiting obstacles, enhancing drug efficacy and bioavailability while reducing toxicity. Therefore, this study proposed NLC-BZN formulations in different compositions prepared by hot-melt homogenization followed by ultrasound, and the optimized formulation was characterized by FTIR, DRX, DSC, and thermogravimetry. Biological activities included in vitro membrane toxicity (red blood cells), fibroblast cell cytotoxicity, and trypanocidal activity against epimastigotes of the Colombian strain of T. cruzi. The optimized NLC-BZN had a small size (110 nm), negative zeta potential (-18.0 mV), and high encapsulation (1.64% of drug loading), as shown by infrared spectroscopy, X-ray diffraction, and thermal analysis. The NLC-BZN also promoted lower in vitro membrane toxicity (<3% hemolysis), and 50% cytotoxic concentration (CC50) for NLC-BZN in L929 fibroblast cells (110.7 µg/mL) was twice the value as the free BZN (51.3 µg/mL). Our findings showed that the NLC-BZN had higher trypanocidal activity than free BZN against the epimastigotes of the resistant Colombian strain, and this novel NLC-BZN formulation proved to be a promising tool in treating Chagas disease and considered suitable for oral and parenteral administration


Subject(s)
Trypanosoma cruzi/isolation & purification , X-Ray Diffraction/instrumentation , Chagas Disease/pathology , Neglected Diseases/classification , Parasitic Diseases/pathology , Spectrum Analysis/instrumentation , Sprains and Strains/classification , Thermogravimetry/methods , In Vitro Techniques/methods , Pharmaceutical Preparations/analysis , Spectroscopy, Fourier Transform Infrared/methods
4.
Dig Dis Sci ; 67(2): 613-621, 2022 02.
Article in English | MEDLINE | ID: mdl-33761089

ABSTRACT

BACKGROUND: Colonoscopic screening and surveillance for colorectal cancer could be made safer and more efficient if endoscopists could predict histology without the need to biopsy and perform histopathology on every polyp. Elastic-scattering spectroscopy (ESS), using fiberoptic probes integrated into standard biopsy tools, can assess, both in vivo and in real time, the scattering and absorption properties of tissue related to its underlying pathology. AIMS: The objective of this study was to evaluate prospectively the potential of ESS to predict polyp pathology accurately. METHODS: We obtained ESS measurements from patients undergoing screening/surveillance colonoscopy using an ESS fiberoptic probe integrated into biopsy forceps. The integrated forceps were used for tissue acquisition, following current standards of care, and optical measurement. All measurements were correlated to the index pathology. A machine learning model was then applied to measurements from 367 polyps in 169 patients to prospectively evaluate its predictive performance. RESULTS: The model achieved sensitivity of 0.92, specificity of 0.87, negative predictive value (NPV) of 0.87, and high-confidence rate (HCR) of 0.84 for distinguishing 220 neoplastic polyps from 147 non-neoplastic polyps of all sizes. Among 138 neoplastic and 131 non-neoplastic polyps ≤ 5 mm, the model achieved sensitivity of 0.91, specificity of 0.88, NPV of 0.89, and HCR of 0.83. CONCLUSIONS: Results show that ESS is a viable endoscopic platform for real-time polyp histology, particularly for polyps ≤ 5 mm. ESS is a simple, low-cost, clinically friendly, optical biopsy modality that, when interfaced with minimally obtrusive endoscopic tools, offers an attractive platform for in situ polyp assessment.


Subject(s)
Adenocarcinoma/diagnosis , Adenomatous Polyps/diagnosis , Colonic Polyps/diagnosis , Colonoscopy/methods , Colorectal Neoplasms/diagnosis , Diagnosis, Computer-Assisted/methods , Spectrum Analysis/methods , Adenocarcinoma/pathology , Adenomatous Polyps/pathology , Artificial Intelligence , Colonic Polyps/pathology , Colorectal Neoplasms/pathology , Humans , Sensitivity and Specificity , Spectrum Analysis/instrumentation
5.
Braz. J. Pharm. Sci. (Online) ; 58: e19233, 2022. tab, graf
Article in English | LILACS | ID: biblio-1374569

ABSTRACT

Abstract In the present study, the metabolite profiling of methanolic extract from aerial parts of Satureja khuzistanica Jamzad, as an endemic medicinal plant from Iran, was evaluated using HPLC-PDA-ESI. Then, the main compound from the extract was isolated and purified by using extensive chromatographic techniques. In addition, the structure of the isolated compounds was elucidated using 1D, 2D NMR, and MS spectrometry, upon which 22 compounds were identified. The antibacterial activity of diosmetin 7-rutinoside (6) and linarin (13) in combination with carvacrol as a major compound of the essential oil was tested against Pseudomonas aeruginosa and Staphylococcus aureus through disc diffusion and minimum inhibitory concentration methods. The results indicated that the linarin, when mixed with carvacrol as the main compounds in the essential oil of the plant, has a satisfactory activity against both Pseudomonas aeruginosa and Staphylococcus aureus with MIC values of 0.16 and 0.18 µg/mL, respectively. Further, the fractional inhibitory concentration (FIC) index indicated that this compound had synergism with carvacrol.


Subject(s)
Plants, Medicinal/anatomy & histology , Oils, Volatile/analysis , Lamiaceae/chemistry , Satureja/classification , Pseudomonas aeruginosa/isolation & purification , Spectrum Analysis/instrumentation , Microbial Sensitivity Tests/instrumentation , Chromatography, High Pressure Liquid/methods
6.
Braz. J. Pharm. Sci. (Online) ; 58: e19967, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384000

ABSTRACT

Abstract Red lima bean (Phaseolus lunatus Linn) Family Fabaceae, has been modified by succinylation and annealing, and used as intra- and extra-granular disintegrants at concentrations of 5 and 10 %w/w in paracetamol tablet formulation in comparison with corn starch BP. The starches were characterised using FT-IR spectroscopy, SEM, proximate analysis, physicochemical and functional properties. FT-IR spectrometry revealed characteristic peaks at 1575.53 and 1713.99 cm-1 for the succinylated starch while the annealed showed no significant difference from the native starch. Modifications did not alter the ovoid shape of the native starch but reduced the particle size. Succinylation improved water absorption capacity, solubility and swelling of lima bean starch but annealing reduced the parameters. Tablets with disintegrants of lima bean starches generally had higher crushing strengths and lower friability than tablets with corn starch. Modifications reduced the disintegration time of the tablets when the starches were incorporated intra-granularly, which suggested particle-particle bond interruption and destruction of hydrogen bonds as mechanism of disintegration. Tablets containing 10 %w/w succinylated red lima bean starch incorporated intra-granularly had the highest disintegration efficiency ratio, DER, indicating a great balance between mechanical and disintegration properties. Modified red lima bean starches incorporated intra-granularly into paracetamol tablets led to faster disintegration and could efficiently substitute corn starch as disintegrant.


Subject(s)
Tablets/pharmacology , Abrus/classification , Starch and Fecula , Acetaminophen/classification , Spectrum Analysis/instrumentation , Spectroscopy, Fourier Transform Infrared/methods
7.
Braz. J. Pharm. Sci. (Online) ; 58: e19753, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384012

ABSTRACT

Abstract The study is aimed to assess the compatibility of bilberry leaf powder extract (BLPE) with six excipients selected for sustained-release (SR) tablet formulation. The BLPE was obtained with the addition of L-arginine and Myo-inositol as the carriers. Thermogravimetric (TG-DTG) analysis and Fourier-transform infrared spectroscopy (FTIR), supported by Pearson correlation analysis, were applied to detect possible interactions in the binary mixtures (1:1) of the BLPE with each excipient. The TG-DTG showed some deviations in the thermal behavior of the BLPE / excipient mixtures. However, only the thermal behavior of magnesium stearate in the mixture significantly differed from individual samples, which suggested chemical interaction for this excipient. The FTIR analysis confirmed that the BLPE is compatible with Eudragit L100, Methocel K4M, Methocel K100LV, Avicel PH-101, and Plasdone S-630. Whereas it undergoes solid-state chemical interaction in the binary mixture with magnesium stearate. According to the FTIR-spectra, it is suggested that this interaction results in the formation of stearic acid and alkalization of the medium. These findings evidence for the possibility of using TG-DTG analysis as an independent thermal technique for compatibility studies and also confirm the earlier reported interaction of basic lubricants, e.g., stearic salts, with active ingredients containing amino groups.


Subject(s)
Behavior , Plant Extracts/analysis , Plant Leaves/classification , Vaccinium myrtillus/adverse effects , Vaccinium myrtillus/metabolism , Delayed-Action Preparations/analysis , Spectrum Analysis/instrumentation , Thermogravimetry/instrumentation , Spectroscopy, Fourier Transform Infrared/methods
8.
Braz. J. Pharm. Sci. (Online) ; 58: e20013, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394062

ABSTRACT

The aim of the present study is to improve the solubility and antimicrobial activity of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin by formulating its inclusion complexes with 2-hydroxypropyl-ß-cyclodextrin in solution and in solid state. The phase solubility study was used to investigate the interactions between 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin and 2-hydroxypropyl-ß-cyclodextrin and to estimate the molar ratio between them. The structural characterization of binary systems (prepared by physical mixing, kneading and solvent evaporation methods) was analysed using the FTIR-ATM spectroscopy. The antimicrobial activity of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin and inclusion complexes prepared by solvent evaporation method was tested by the diffusion and dilution methods on various strains of microorganisms. The results of phase solubility studies showed that 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin formed the inclusion complexes with 2-hydroxypropyl-ß-cyclodextrin of AP type. The solubility of 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin was increased 64.05-fold with 50% w/w of 2-hydroxypropyl-ß-cyclodextrin at 37 oC. The inclusion complexes in solid state, prepared by the solvent evaporation method, showed higher solubility in purified water and in phosphate buffer solutions in comparison with 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin alone. The inclusion complexes prepared by solvent evaporation method showed higher activity on Bacillus subtilis and Staphylococcus aureus compared to uncomplexed 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin due to improved aqueous solubility, thus increasing the amount of available 3-(3-(2-chlorophenyl)prop-2-enoyl)-4-hydroxycoumarin that crosses the bacterial membrane.


Subject(s)
Solubility , Cyclodextrins/agonists , Anti-Infective Agents , Spectrum Analysis/instrumentation , Staphylococcus aureus/classification , Bacillus subtilis/classification , Spectroscopy, Fourier Transform Infrared , Dilution
9.
Nutrients ; 13(11)2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34836051

ABSTRACT

Dietary behavior change is difficult to accurately measure in a low-income youth population. Objective tools to measure fruit and vegetable consumption without relying on self-report present the opportunity to do this with less respondent burden and bias. A promising tool for quantifying fruit and vegetable consumption via proxy is skin carotenoids as measured by reflection spectroscopy through a device called the Veggie Meter®. To assess whether the Veggie Meter® is able to detect changes in skin carotenoids as a proxy for fruit and vegetable consumption in a low-income school setting, skin carotenoid measurements were collected at three time points, along with student level demographics, anthropometric measurements, and nutrition knowledge. A secondary goal of this study was to refine the protocol to be used based on researcher observations. Repeated measures analysis of variance with Bonferroni correction for multiple comparisons indicate that there was a significant difference in VM scores over the course of the study (F(2, 68) = 6.63, p = 0.002), with an increase in skin carotenoids from Fall 2018 to Spring 2019 (p = 0.005). This increase was sustained over the summer months when measured in Fall 2019. Changes to the protocol included the addition of a hand cleaning step and using the non-dominant ring finger for data collection. With these refinements, the results demonstrate that the Veggie Meter® is usable as a non-invasive tool for measuring fruit and vegetable consumption in a population that is traditionally difficult to assess.


Subject(s)
Carotenoids/analysis , Diet Surveys/instrumentation , Poverty/statistics & numerical data , Spectrum Analysis/instrumentation , Students/statistics & numerical data , Adolescent , Analysis of Variance , California , Child , Diet Surveys/methods , Feasibility Studies , Feeding Behavior/physiology , Female , Fruit , Humans , Male , Nutrition Assessment , Schools , Seasons , Skin/chemistry , Spectrum Analysis/methods , Vegetables
10.
PLoS One ; 16(11): e0260056, 2021.
Article in English | MEDLINE | ID: mdl-34780569

ABSTRACT

An area of ancient and semi-natural woodland (ASNW) has been investigated by applied aerial spectroscopy using an unmanned aerial vehicle (UAV) with multispectral image (MSI) camera. A novel normalised difference spectral index (NDSI) algorithm was developed using principal component analysis (PCA). This novel NDSI was then combined with a simple segmentation method of thresholding and applied for the identification of native tree species as well as the overall health of the woodland. Using this new approach allowed the identification of trees at canopy level, across 7.4 hectares (73,934 m2) of ASNW, as oak (53%), silver birch (37%), empty space (9%) and dead trees (1%). This UAV derived data was corroborated, for its accuracy, by a statistically valid ground-level field study that identified oak (47%), silver birch (46%) and dead trees (7.4%). This simple innovative approach, using a low-cost multirotor UAV with MSI camera, is both rapid to deploy, was flown around 100 m above ground level, provides useable high resolution (5.3 cm / pixel) data within 22 mins that can be interrogated using readily available PC-based software to identify tree species. In addition, it provides an overall oversight of woodland health and has the potential to inform a future woodland regeneration strategy.


Subject(s)
Remote Sensing Technology/instrumentation , Spectrum Analysis/instrumentation , Trees/classification , Algorithms , Conservation of Natural Resources , England , Forests , Principal Component Analysis , Unmanned Aerial Devices
11.
Plant Physiol ; 187(4): 2623-2636, 2021 12 04.
Article in English | MEDLINE | ID: mdl-34601616

ABSTRACT

Environmental stresses from climate change can alter source-sink relations during plant maturation, leading to premature senescence and decreased yields. Elucidating the genetic control of natural variations for senescence in wheat (Triticum aestivum) can be accelerated using recent developments in unmanned aerial vehicle (UAV)-based imaging techniques. Here, we describe the use of UAVs to quantify senescence in wheat using vegetative indices (VIs) derived from multispectral images. We detected senescence with high heritability, as well as its impact on grain yield (GY), in a doubled-haploid population and parent cultivars at various growth time points (TPs) after anthesis in the field. Selecting for slow senescence using a combination of different UAV-based VIs was more effective than using a single ground-based vegetation index. We identified 28 quantitative trait loci (QTL) for vegetative growth, senescence, and GY using a 660K single-nucleotide polymorphism array. Seventeen of these new QTL for VIs from UAV-based multispectral imaging were mapped on chromosomes 2B, 3A, 3D, 5A, 5D, 5B, and 6D; these QTL have not been reported previously using conventional phenotyping methods. This integrated approach allowed us to identify an important, previously unreported, senescence-related locus on chromosome 5D that showed high phenotypic variation (up to 18.1%) for all UAV-based VIs at all TPs during grain filling. This QTL was validated for slow senescence by developing kompetitive allele-specific PCR markers in a natural population. Our results suggest that UAV-based high-throughput phenotyping is advantageous for temporal assessment of the genetics underlying for senescence in wheat.


Subject(s)
Chromosome Mapping , Crops, Agricultural/physiology , Quantitative Trait Loci , Spectrum Analysis/methods , Triticum/physiology , Unmanned Aerial Devices , Plant Senescence , Spectrum Analysis/instrumentation
12.
Physiol Rep ; 9(16): e14995, 2021 08.
Article in English | MEDLINE | ID: mdl-34427400

ABSTRACT

In vitro determination of the hemoglobin oxygen dissociation curve (ODC) requires highly elaborate, specialized, and costly technical equipment. In addition, there is a lack of methods that combine reliable ODC recordings with high throughput in small blood samples for routine analysis. We here introduce a modified, commercial 96-well plate with an integrated unidirectional gas flow system specifically adapted for use in fluorescence microplate readers. Up to 92 samples of whole or hemolyzed, buffered or unbuffered blood, including appropriate controls or internal standard hemoglobin solutions, can be analyzed within ~25 min. Oxygen saturation is measured in each well with dual wavelength spectroscopy, and oxygen partial pressure using fluorescence lifetime of commercial oxygen sensors at the in- and outlet ports of the gas-flow system. Precision and accuracy of this method have been determined and were compared with those of a standard method. We further present two applications that exemplarily highlight the usefulness and impact of this novel approach for clinical diagnostics or basic research.


Subject(s)
Blood Cells/metabolism , High-Throughput Screening Assays/instrumentation , Oxygen/metabolism , Cells, Cultured , Hematologic Tests/instrumentation , Hematologic Tests/methods , Hemoglobins/metabolism , High-Throughput Screening Assays/methods , Humans , Spectrum Analysis/instrumentation , Spectrum Analysis/methods
13.
Plant J ; 108(3): 870-885, 2021 11.
Article in English | MEDLINE | ID: mdl-34407245

ABSTRACT

At the morphological and anatomical levels, the ionome, or the elemental composition of an organism, is an understudied area of plant biology. In particular, the ionomic responses of plant-pathogen interactions are scarcely described, and there are no studies on immune reactions. In this study we explored two X-ray fluorescence (XRF)-based ionome visualisation methods (benchtop- and synchrotron-based micro-XRF [µXRF]), as well as the quantitative inductively coupled plasma optical emission spectroscopy (ICP-OES) method, to investigate the changes that occur in the ionome of compatible and incompatible plant-pathogen interactions. We utilised the agronomically important and comprehensively studied interaction between potato (Solanum tuberosum) and the late blight oomycete pathogen Phytophthora infestans as an example. We used one late blight-susceptible potato cultivar and two resistant transgenic plant lines (only differing from the susceptible cultivar in one or three resistance genes) both in control and P. infestans-inoculated conditions. In the lesions from the compatible interaction, we observed rearrangements of several elements, including a decrease of the mobile macronutrient potassium (K) and an increase in iron (Fe) and manganese (Mn), compared with the tissue outside the lesion. Interestingly, we observed distinctly different distribution patterns of accumulation at the site of inoculation in the resistant lines for calcium (Ca), magnesium (Mg), Mn and silicon (Si) compared to the susceptible cultivar. The results reveal different ionomes in diseased plants compared to resistant plants. Our results demonstrate a technical advance and pave the way for deeper studies of the plant-pathogen ionome in the future.


Subject(s)
Host-Pathogen Interactions/physiology , Ions/analysis , Phytophthora infestans/pathogenicity , Solanum tuberosum/microbiology , Spectrum Analysis/methods , Disease Susceptibility , Ions/metabolism , Metals/metabolism , Phosphorus/metabolism , Plant Diseases/microbiology , Plants, Genetically Modified , Spectrometry, X-Ray Emission/instrumentation , Spectrometry, X-Ray Emission/methods , Spectrum Analysis/instrumentation , Synchrotrons
14.
Chem Commun (Camb) ; 57(58): 7156-7159, 2021 Jul 20.
Article in English | MEDLINE | ID: mdl-34184021

ABSTRACT

A low-cost and multi-channel smartphone-based spectrometer was developed for LIBS. As the CMOS detector is two-dimensional, simultaneous multichannel detection was achieved by coupling a linear array of fibres for light collection. Thus, besides the atomic information, the spectral images containing the propagation and spatial distribution characters of a laser induced plasma plume could be recorded. With these additional features, accurate rock type prediction was achieved by processing the raw data directly through a deep learning model.


Subject(s)
Deep Learning , Smartphone , Algorithms , Equipment Design , Image Processing, Computer-Assisted , Spectrum Analysis/instrumentation
15.
Nat Commun ; 12(1): 3246, 2021 05 31.
Article in English | MEDLINE | ID: mdl-34059690

ABSTRACT

Biosensors are indispensable tools for public, global, and personalized healthcare as they provide tests that can be used from early disease detection and treatment monitoring to preventing pandemics. We introduce single-wavelength imaging biosensors capable of reconstructing spectral shift information induced by biomarkers dynamically using an advanced data processing technique based on an optimal linear estimator. Our method achieves superior sensitivity without wavelength scanning or spectroscopy instruments. We engineered diatomic dielectric metasurfaces supporting bound states in the continuum that allows high-quality resonances with accessible near-fields by in-plane symmetry breaking. The large-area metasurface chips are configured as microarrays and integrated with microfluidics on an imaging platform for real-time detection of breast cancer extracellular vesicles encompassing exosomes. The optofluidic system has high sensing performance with nearly 70 1/RIU figure-of-merit enabling detection of on average 0.41 nanoparticle/µm2 and real-time measurements of extracellular vesicles binding from down to 204 femtomolar solutions. Our biosensors provide the robustness of spectrometric approaches while substituting complex instrumentation with a single-wavelength light source and a complementary-metal-oxide-semiconductor camera, paving the way toward miniaturized devices for point-of-care diagnostics.


Subject(s)
Biosensing Techniques , Breast Neoplasms/diagnosis , Microfluidic Analytical Techniques/instrumentation , Point-of-Care Testing , Refractometry/instrumentation , Breast Neoplasms/blood , Exosomes/chemistry , Female , Humans , Microfluidic Analytical Techniques/methods , Nanoparticles/chemistry , Refractometry/methods , Spectrum Analysis/instrumentation , Spectrum Analysis/methods
16.
Methods Mol Biol ; 2277: 101-124, 2021.
Article in English | MEDLINE | ID: mdl-34080147

ABSTRACT

This chapter describes the complementary experimental techniques Electron Transmission Spectroscopy and Dissociative Electron Attachment Spectroscopy, two of the most suitable means for investigating interactions between electrons and gas-phase molecules, resonance formation of temporary molecular negative ions, and their possible decay through the dissociative electron attachment (DEA) mechanism. The latter can be seen as the gas-phase counterpart of the transfer of a solvated electron in solution, accompanied by dissociation of the molecular anion, referred to as dissociative electron transfer (DET). DET takes place in vivo under reductive conditions, for instance, in the intermembrane space of mitochondria under interaction of xenobiotic molecules possessing high electron affinity with electrons "leaked" from the mitochondrial respiratory chain. A likely mechanism of the toxic activity of dichlorodiphenyltrichloroethane based on its DEA properties is briefly outlined, and compared with the well-established harmful effects of the model toxicant carbon tetrachloride ascribed to reductive dechlorination in a cellular ambient. A possible mechanism of the antioxidant activity of polyphenolic compounds present near the main site of superoxide anion production in mitochondria is also briefly discussed.


Subject(s)
Mitochondria/chemistry , Mitochondria/metabolism , Spectrum Analysis/methods , Antioxidants/chemistry , Antioxidants/metabolism , DDT/chemistry , DDT/toxicity , Electron Transport , Electrons , Mitochondrial Membranes , Polyphenols/chemistry , Polyphenols/metabolism , Spectrum Analysis/instrumentation , Xenobiotics/chemistry , Xenobiotics/toxicity
17.
Appl Radiat Isot ; 174: 109751, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33962118

ABSTRACT

The Tehran Research Reactor is the only appropriate and available neutron source in Iran for clinical boron neutron capture therapy (BNCT). One of the requirements for BNCT is to carefully evaluate and measure the therapeutic neutron beam (epithermal neutrons) as well as the fast and thermal neutron components for successful treatment. In this research, a multi-moderator neutron spectrometer (MMNS) with LiI(Eu) scintillator as neutron counter was proposed for these measurements in the range of 10-11 eV to 15 MeV. The results confirmed promising precision of the designed MMNS for the epithermal spectrum; however, the angular dependency of the therapeutic beam due to any probable change in the beam-shaping assembly should be considered.


Subject(s)
Boron Neutron Capture Therapy/methods , Neutrons , Spectrum Analysis/instrumentation , Borates/chemistry , Iran , Polyethylene/chemistry , Water/chemistry
18.
Breast Dis ; 40(2): 85-93, 2021.
Article in English | MEDLINE | ID: mdl-33646139

ABSTRACT

BACKGROUND: Bioimpedance spectroscopy has been suggested as a useful tool for early diagnosis of breast cancer-related lymphedema (BCRL). We aimed to describe the outcomes of published studies that evaluated bioimpedance analysis as a method for prospective surveillance and early diagnosis of BCRL. METHODS: We queried the PubMed, Ovid Medline, and EMBASE databases to identify studies that evaluated use of bioimpedance spectroscopy as a diagnostic tool. We used the keywords "bioimpedance" AND ("lymphedema" OR "lymphoedema") in the search. Only English-language studies that reported quantitative outcomes for patients with BCRL were included. RESULTS: Of 152, 235 and 116 identified articles in PubMed, Ovid Medline and EMBASE databases, only 22 were included. Use of bioimpedance analysis for prospective surveillance has been shown to prevent chronic BCRL. All the cross-sectional and retrospective studies that evaluated bioimpedance for diagnosis of BCRL reported significantly different L-Dex scores between lymphedema patients and healthy participants; in addition, bioimpedance scores were positively correlated with volume of lymphedema. CONCLUSION: Bioimpedance analysis is a potential tool with demonstrated benefits for prevention of chronic BCRL and may be an economic and great alternative for early diagnosis of BCRL.


Subject(s)
Breast Cancer Lymphedema/diagnosis , Breast Neoplasms/complications , Early Detection of Cancer/methods , Spectrum Analysis/methods , Cross-Sectional Studies , Early Detection of Cancer/instrumentation , Epidemiological Monitoring , Female , Humans , Lymph Node Excision/adverse effects , Prospective Studies , Retrospective Studies , Spectrum Analysis/instrumentation
19.
Rev Sci Instrum ; 92(2): 023104, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33648131

ABSTRACT

Structures, kinetics, and chemical reactivities at interfaces and surfaces are key to understanding many of the fundamental scientific problems related to chemical, material, biological, and physical systems. These steady-state and dynamical properties at interfaces and surfaces require even-order techniques with time-resolution and spectral-resolution. Here, we develop fourth-order interface-/surface-specific two-dimensional electronic spectroscopy, including both two-dimensional electronic sum frequency generation (2D-ESFG) spectroscopy and two-dimensional electronic second harmonic generation (2D-ESHG) spectroscopy, for structural and dynamics studies of interfaces and surfaces. The 2D-ESFG and 2D-ESHG techniques were based on a unique laser source of broadband short-wave IR from 1200 nm to 2200 nm from a home-built optical parametric amplifier. With the broadband short-wave IR source, surface spectra cover most of the visible light region from 480 nm to 760 nm. A translating wedge-based identical pulses encoding system (TWINs) was introduced to generate a phase-locked pulse pair for coherent excitation in the 2D-ESFG and 2D-ESHG. As an example, we demonstrated surface dark states and their interactions of the surface states at p-type GaAs (001) surfaces with the 2D-ESFG and 2D-ESHG techniques. These newly developed time-resolved and interface-/surface-specific 2D spectroscopies would bring new information for structure and dynamics at interfaces and surfaces in the fields of the environment, materials, catalysis, and biology.


Subject(s)
Spectrum Analysis/instrumentation , Amplifiers, Electronic , Surface Properties , Vibration
20.
Acta sci., Health sci ; 43: e49846, Feb.11, 2021.
Article in English | LILACS | ID: biblio-1368509

ABSTRACT

Fibromyalgia is a disorder of the central nervous system, with the presence of chronic generalized pain, fatigue, morning stiffness, anxiety and depression symptoms. Higher amplitudes of the frequency band alpha2 have been associated with higher relaxationin this population. In the present study, we analysed the association between pain, anxiety, and the spectral power of alpha2 frontal in women with fibromyalgia. Thirty-one women diagnosed with fibromyalgia, for at least three months, took part in the study. Results revealed a statistically significant positive relationship between pain and anxiety levels. However, we found no association between the spectral power of alpha2 in the frontal cortex and the measures between anxiety and pain in the patients. Present findings emphasize the importance of understanding the cortical activity and the central control mechanisms in fibromyalgia.


Subject(s)
Humans , Female , Adult , Middle Aged , Pain/diagnosis , Women/psychology , Fibromyalgia/diagnosis , Frontal Lobe/pathology , Anxiety/psychology , Spectrum Analysis/instrumentation , Depression/psychology , Electroencephalography/instrumentation
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