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1.
Mol Omics ; 20(1): 27-36, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37751172

RESUMO

Cancer is one of the deadliest diseases in humans and dogs. Nevertheless, most tumor types spread faster in canines, and early cancer detection methods are necessary to enhance animal survival. Here, cerumen (earwax) was tested as a source of potential biomarkers for cancer evaluation in dogs. Earwax samples from dogs were collected from tumor-bearing and clinically healthy dogs, followed by Headspace/Gas Chromatography-Mass Spectrometry (HS/GC-MS) analyses and multivariate statistical workflow. An evolutionary-based multivariate algorithm selected 18 out of 128 volatile metabolites as a potential cancer biomarker panel in dogs. The candidate biomarkers showed a full discrimination pattern between tumor-bearing dogs and cancer-free canines with high accuracy in the test dataset: an accuracy of 95.0% (75.1-99.9), and sensitivity and specificity of 100.0% and 92.9%, respectively. In summary, this work raises a new perspective on cancer diagnosis in dogs, being carried out painlessly and non-invasive, facilitating sample collection and periodic application in a veterinary routine.


Assuntos
Neoplasias , Compostos Orgânicos Voláteis , Humanos , Cães , Animais , Cerume/química , Cerume/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Neoplasias/diagnóstico , Neoplasias/veterinária , Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos
2.
Environ Monit Assess ; 195(2): 270, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36607465

RESUMO

Water analyses in conjunction with hydrological and geotechnical investigations were carried out to assess the potential for groundwater contamination from the decomposition of buried human bodies. Water samples were collected from 2007 to 2018 in three monitoring wells built within the cemetery area. Water quality was evaluated based on the determination of 25 analytical parameters (20 physical-chemical and 5 microbiological). Laboratory data reported by the local sewage water company for water collected in household cisterns located outside the cemetery area were also evaluated. Multivariate analysis showed a similar pattern between iron content, turbidity, and rainfall data collected at the rainfall station closest to the study area. This behavior is a direct consequence of soil leaching (oxisol). The physical characterization of the soil of the unsaturated area above the aquifer indicates that the absorption of body waste by the soil is favored, preventing surface contaminants from reaching the aquifer. This work also found that the water samples collected outside the cemetery area do not comply with the Brazilian limits for drinking water. In conclusion, water samples collected from monitoring wells located within the cemetery area have little to none impact on both subsurface and underground contamination.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Humanos , Monitoramento Ambiental , Cemitérios , Água Subterrânea/química , Solo , Análise Multivariada , Poluentes Químicos da Água/análise
3.
Metabolomics ; 18(7): 42, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739279

RESUMO

INTRODUCTION: Trypanosomiasis caused by Trypanosoma vivax (T. vivax, subgenus Duttonella) is a burden disease in bovines that induces losses of billions of dollars in livestock activity worldwide. To control the disease, the first step is identifying the infected animals at early stages. However, convention tools for animal infection detection by T. vivax present some challenges, facilitating the spread of the pathogenesis. OBJECTIVES: This work aims to develop a new procedure to identify infected bovines by T. vivax using cerumen (earwax) in a volatilomic approach, here named cerumenolomic, which is performed in an easy, quick, accurate, and non-invasive manner. METHODS: Seventy-eight earwax samples from Brazilian Curraleiro Pé-Duro calves were collected in a longitudinal study protocol during health and inoculated stages. The samples were analyzed using Headspace/Gas Chromatography-Mass Spectrometry followed by multivariate analysis approaches. RESULTS: The cerumen analyses lead to the identification of a broad spectrum of volatile organic metabolites (VOMs), of which 20 VOMs can discriminate between healthy and infected calves (AUC = 0.991, sensitivity = 0.967, specificity = 1.000). Furthermore, 13 VOMs can indicate a pattern of discrimination between the acute and chronic phases of the T. vivax infection in the animals (AUC = 0.989, sensitivity = 0.944, specificity = 1.000). CONCLUSION: The cerumen volatile metabolites present alterations in their occurrence during the T.vivax infection, which may lead to identifying the infection in the first weeks of inoculation and discriminating between the acute and chronic phases of the illness. These results may be a breakthrough to avoid the T. vivax outbreak and provide a faster clinical approach to the animal.


Assuntos
Metabolômica , Tripanossomíase Bovina , Animais , Brasil/epidemiologia , Bovinos , Estudos Longitudinais , Trypanosoma vivax , Tripanossomíase Bovina/diagnóstico
4.
Biomed Chromatogr ; 34(11): e4935, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32598079

RESUMO

An innovative volatolomic approach employs the detection of biomarkers present in cerumen (earwax) to identify cattle intoxication by Stryphnodendron rotundifolium Mart., Fabaceae (popularly known as barbatimão). S. rotundifolium is a poisonous plant with the toxic compound undefined and widely distributed throughout the Brazilian territory. Cerumen samples from cattle of two local Brazilian breeds ('Curraleiro Pé-Duro' and 'Pantaneiro') were collected during an experimental intoxication protocol and analyzed using headspace (HS)/GC-MS followed by multivariate analysis (genetic algorithm for a partial least squares, cluster analysis, and classification and regression trees). A total of 106 volatile organic metabolites were identified in the cerumen samples of bovines. The intoxication by S. rotundifolium influenced the cerumen volatolomic profile of the bovines throughout the intoxication protocol. In this way, it was possible to detect biomarkers for cattle intoxication. Among the biomarkers, 2-octyldecanol and 9-tetradecen-1-ol were able to discriminate all samples between intoxicated and nonintoxicated bovines. The cattle intoxication diagnosis by S. rotundifolium was accomplished by applying the cerumen analysis using HS/GC-MS, in an easy, accurate, and noninvasive way. Thus, the proposed bioanalytical chromatography protocol is a useful tool in veterinary applications to determine this kind of intoxication.


Assuntos
Doenças dos Bovinos/diagnóstico , Cerume/química , Fabaceae/efeitos adversos , Intoxicação por Plantas/diagnóstico , Intoxicação por Plantas/veterinária , Animais , Biomarcadores/análise , Brasil , Bovinos , Cromatografia Gasosa-Espectrometria de Massas , Análise dos Mínimos Quadrados , Masculino , Compostos Orgânicos Voláteis/análise
5.
J Am Soc Mass Spectrom ; 31(7): 1525-1535, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32453588

RESUMO

Petroleomics, which is the characterization, separation, and quantification of the components of petroleum and crude oil, is an emerging area of study. However, the repertoire of analytical methods available to understand commercial automotive lubricant oils (ALOs) is very limited. Ambient mass spectrometry is one of the most sensitive analytical methods for real-time and in situ chemical analysis. With this technique, the chemical fingerprinting of ALOs can be performed quickly and simply using dielectric barrier discharge ionization time-of-flight mass spectrometry. In this study, the mass spectra of 35 samples were obtained without any sample preparation in positive-ion mode, and no carryover was observed. To elucidate the similarities and differences between the ALO samples, the data generated from these spectra were analyzed using four chemometric techniques: principal component analysis, multivariate curve resolution, hierarchical cluster analysis, and pattern recognition entropy. The ALO samples were readily differentiated according to their American Petroleum Institute classification and base oil types: mineral, semisynthetic, and synthetic. The development of this new methodology will aid in the semiquantitative control analysis of ALOs and offers an improved ability to identify the components therein.

6.
Pharmacogn Mag ; 13(50): 270-274, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28539720

RESUMO

BACKGROUND: Tithonia diversifolia belongs to the Asteraceae family. The leaves of T. diversifolia have been studied lately because of the presence of tagitinin C. OBJECTIVE: Looking for an easy and inexpensive method to extract tagitinin C from T. diversifolia leaves, this work aims to conduct a screening to evaluate the influence of different experimental factors using the dynamic maceration and ultrasound-assisted extraction methods with 23 factorial design based on response surface methodology in enhancing this chemical marker extraction. MATERIALS AND METHODS: The experimental factors were: extraction time (ET) of 30 and 60 minutes, solid: liquid ratio (SLR) of 5 and 10 grams/grams and ethanolic strength (ES) 48 and 96% (w/w). The experiments were done tripled. The content of tagitinin C in each produced extract was quantified by HPLC method. RESULTS: The highest concentrations of tagitinin C obtained under the experimental design were 0.53 mg/mL and 0.71 mg/mL, respectively for dynamic maceration (DM) and ultrasound-assisted extraction (UAE) from Tithonia diversifolia powdered leaves. For the UAE method, the main parameter for higher contents of tagitinin C was the solid: liquid ratio, followed by the ethanolic strength, and the extraction time was not significant for this method. As for the DM method, all the parameters (SLR, ES, and ET) were significant for a higher content of tagitinin C. CONCLUSION: Based on the obtained results, it was revealed that the ultrasound-assisted extraction was more effective than dynamic maceration for tagitinin C extraction from T. diversifolia powdered leaves. SUMMARY: Tithonia diversifolia leaves possess tagitinin C, a sesquiterpene lactone, as an important secondary metabolite with several biological activities, such as antimalarial, gastroprotective, chemotherapeutic adjuvants, and toxic activities.Ultrasound-assisted extraction was more effective to obtain higher levels of tagitinin C when compared with dynamic maceration extraction.Factorial design can be employed as a screening tool to find the effects of factors investigated in the extraction processes. Abbreviation used: DME: dynamic maceration extraction, UAE: ultrasound-assisted extraction, ET: extraction time, ES: ethanolic strength, SLR: solid:liquid ratio, Tag C: tagitinin C, HPLC: high-performance liquid chromatography.

7.
Food Chem ; 211: 465-73, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27283656

RESUMO

A green solvent-based optimization for rosmarinic acid (RA), carnosol (COH), and carnosic acid (CA) extraction, the three main antioxidants from rosemary, was performed. The conventional solid-liquid extraction was optimized using a central composite design (CCD) followed by the desirability approach. In the CCD analysis the quantitative effects of extraction time (4.8-55.2min), liquid-to-solid ratio (4.6-21.4mLg(-1)), and ethanol content (44.8-95.2% v/v) were determined for the extracted amount of antioxidants, their concentrations in the extract, and the extraction yield. Samples were analyzed by HPLC and the antioxidants were identified by comparison with pure standard retention times and UV spectra. The desirability function that simultaneously maximizes the antioxidants extraction and their concentrations in the final product was validated. The extraction using a hydroalcoholic solution 70% v/v, at low liquid-to-solid ratio (5mLg(-1)), and after 55-min yielded an antioxidant recovery rate of 89.8%, and a final product 4.75 times richer in the main antioxidants than the raw material.


Assuntos
Abietanos/análise , Antioxidantes/análise , Cinamatos/análise , Depsídeos/análise , Extratos Vegetais/análise , Rosmarinus/química , Pós/química , Ácido Rosmarínico
8.
Talanta ; 129: 143-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25127577

RESUMO

Power transformers are essential components in electrical energy distribution. One of their most important parts is the insulation system, consisting of Kraft paper immersed in insulating oil. Interfacial tension and color are major parameters used for assessing oil quality and the system׳s degradation. This work proposes the use of near infrared (NIR), molecular fluorescence, and (1)H nuclear magnetic resonance (NMR) spectroscopy methods combined with chemometric multivariate calibration methods (Partial Least Squares - PLS) to predict interfacial tension and color in insulating mineral oil samples. Interfacial tension and color were also determined using tensiometry and colorimetry as standard reference methods, respectively. The best PLS model was obtained when NIR, fluorescence, and NMR data were combined (data fusion), demonstrating synergy among them. An optimal PLS model was calculated using the selected group of variables according to their importance on PLS projections (VIP). The root mean square errors of prediction (RMSEP) values of 2.9 mN m(-1) and 0.3 were estimated for interfacial tension and color, respectively. Mean relative standard deviations of 1.5% for interfacial tension and 6% for color were registered, meeting quality control requirements set by electrical energy companies. The methods proposed in this work are rapid and simple, showing great advantages over traditional approaches, which are slow and environmentally unfriendly due to chemical waste generation.

9.
Acta Chim Slov ; 61(4): 778-85, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551717

RESUMO

Powder X-ray diffraction patterns for 29 samples of magnetite, acquired using a conventional diffractometer, were used to build PLS calibration-based methods and variable selection to estimate mean crystallite size of magnetite directly from powder X-ray diffraction patterns. The best IPLS model corresponds to the Bragg reflections at 35.4° (h k l = 3 1 1), 43.0° (h k l = 4 0 0), 53.6° (h k l = 4 2 2), and 57.0° (h k l = 5 1 1) in 2θ. The best model was a GA-PLS which produced a model with RMSEP of 0.9 nm, and a correlation coefficient of 0.9976 between mean crystallite sizes calculated using Williamson-Hall approach and the ones predicted by GA-PLS method. These results indicate that magnetite mean crystallite sizes can be predicted directly from Powder X-Ray Diffraction and multivariate calibration using PLS variable selection approach.

10.
J Phys Chem A ; 113(27): 7972-8, 2009 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-19522474

RESUMO

The infrared fundamental intensities of benzene and hexafluorobenzene have been calculated at the MP2/6-311++G(3d,3p) level. The theoretical values are in excellent agreement with the averaged experimental C(6)H(6) results having a rms error of 15.3 km mol(-1). However, the theory badly underestimates the CF stretching and ring deformation intensities of C(6)F(6) having an overall rms error of 141 km mol(-1). The theoretical results confirm the dipole moment derivative signs previously attributed on the basis of the comparison of C(6)H(6) and C(6)D(6) derivatives and semiempirical molecular orbital results. A quantum theory atoms in molecules charge-charge flux-dipole flux interpretation of the theoretical results shows that electronic density changes for out-of-plane vibrations can be explained using a simple bond moment-rehybridization moment model proposed many years ago. However, these changes were found to be much more complicated for the in-plane vibrations involving important charge flux and dipole flux contributions for both molecules as well as contributions from the displacement of equilibrium atomic charges for hexafluorobenzene.

11.
J Phys Chem A ; 109(3): 466-77, 2005 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-16833367

RESUMO

The CIS and EOM-CCSD adiabatic geometries for the first excited states of a set of small molecules (C2H4, C2H2, H2C=O, H2C=S, CS2, CO2, SO2, NO2) have been calculated using the 6-311++G** basis set to see if the former geometries can be good starting points for optimizations at the latter theoretical level. With most of the molecules, there is fairly good agreement between the results from the two methods, and EOM-CCSD gives good agreement with the available experimental data. A detailed discussion of the lowest-lying singlet excited states in CO2 and CS2 is presented, highlighting the pronounced differences in electronic character and equilibrium structure displayed by these isovalent species. The origins of the structural distortions that are frequently found for the adiabatic excited states are examined with the aid of deformation density plots and the electron localization function (ELF).

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