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3.
GigaByte ; 2022: gigabyte50, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36824514

RESUMO

Between 2012 and 2014, 715 green coffee samples were gathered by Almacafé S.A. (Bogotá, Colombia) from 27 countries. These were analysed at the nuclear magnetic resonance (NMR) laboratory at Universidad del Valle (Cali, Colombia). Over 1000 methanolic coffee extracts were prepared and 4563 spectra were acquired in a fully automatic manner using a 400 ï»¿MHz NMR spectrometer (Bruker Biospin, Germany). The dataset spans the variance that could be expected for an industrial application of origin monitoring, including samples from different harvest times, collected over several years, and processed by at least two distinct operators. The resulting 1D and 2D spectra can be used to develop and evaluate feature extraction methods, multivariate algorithms, and automation monitoring techniques. They can also be used as datasets for teaching, or as a reference for new studies of similar samples and approaches.

5.
PLoS One ; 13(2): e0190958, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29438405

RESUMO

Breast cancer (BC) is a highly heterogeneous disease associated with metabolic reprogramming. The shifts in the metabolome caused by BC still lack data from Latin populations of Hispanic origin. In this pilot study, metabolomic and lipidomic approaches were performed to establish a plasma metabolic fingerprint of Colombian Hispanic women with BC. Data from 1H-NMR, GC-MS and LC-MS were combined and compared. Statistics showed discrimination between breast cancer and healthy subjects on all analytical platforms. The differentiating metabolites were involved in glycerolipid, glycerophospholipid, amino acid and fatty acid metabolism. This study demonstrates the usefulness of multiplatform approaches in metabolic/lipid fingerprinting studies to broaden the outlook of possible shifts in metabolism. Our findings propose relevant plasma metabolites that could contribute to a better understanding of underlying metabolic shifts driven by BC in women of Colombian Hispanic origin. Particularly, the understanding of the up-regulation of long chain fatty acyl carnitines and the down-regulation of cyclic phosphatidic acid (cPA). In addition, the mapped metabolic signatures in breast cancer were similar but not identical to those reported for non-Hispanic women, despite racial differences.


Assuntos
Neoplasias da Mama/sangue , Carcinoma Ductal de Mama/sangue , Lipídeos/sangue , Adulto , Idoso , Análise Química do Sangue/métodos , Estudos de Casos e Controles , Colômbia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hispânico ou Latino , Humanos , Espectroscopia de Ressonância Magnética , Redes e Vias Metabólicas , Metabolômica/métodos , Pessoa de Meia-Idade , Projetos Piloto
6.
Int J Anal Chem ; 2017: 7210463, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29201055

RESUMO

The sensorial properties of Colombian coffee are renowned worldwide, which is reflected in its market value. This raises the threat of fraud by adulteration using coffee grains from other countries, thus creating a demand for robust and cost-effective methods for the determination of geographical origin of coffee samples. Spectroscopic techniques such as Nuclear Magnetic Resonance (NMR), near infrared (NIR), and mid-infrared (mIR) have arisen as strong candidates for the task. Although a body of work exists that reports on their individual performances, a faithful comparison has not been established yet. We evaluated the performance of 1H-NMR, Attenuated Total Reflectance mIR (ATR-mIR), and NIR applied to fraud detection in Colombian coffee. For each technique, we built classification models for discrimination by species (C. arabica versus C. canephora (or robusta)) and by origin (Colombia versus other C. arabica) using a common set of coffee samples. All techniques successfully discriminated samples by species, as expected. Regarding origin determination, ATR-mIR and 1H-NMR showed comparable capacity to discriminate Colombian coffee samples, while NIR fell short by comparison. In conclusion, ATR-mIR, a less common technique in the field of coffee adulteration and fraud detection, emerges as a strong candidate, faster and with lower cost compared to 1H-NMR and more discriminating compared to NIR.

7.
J Anal Methods Chem ; 2016: 8564584, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27516919

RESUMO

In a previous work using (1)H-NMR we reported encouraging steps towards the construction of a robust expert system for the discrimination of coffees from Colombia versus nearby countries (Brazil and Peru), to assist the recent protected geographical indication granted to Colombian coffee in 2007. This system relies on fingerprints acquired on a 400 MHz magnet and is thus well suited for small scale random screening of samples obtained at resellers or coffee shops. However, this approach cannot easily be implemented at harbour's installations, due to the elevated operational costs of cryogenic magnets. This limitation implies shipping the samples to the NMR laboratory, making the overall approach slower and thereby more expensive and less attractive for large scale screening at harbours. In this work, we report on our attempt to obtain comparable classification results using alternative techniques that have been reported promising as an alternative to NMR: GC-MS and GC-C-IRMS. Although statistically significant information could be obtained by all three methods, the results show that the quality of the classifiers depends mainly on the number of variables included in the analysis; hence NMR provides an advantage since more molecules are detected to obtain a model with better predictions.

9.
Ann Hepatol ; 10(1): 43-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21301009

RESUMO

BACKGROUND/AIM: The main objective of this study was to describe the profile of patients who were benefitted in a collective effort to perform liver biopsies in Bahia, Brazil. METHOD: A cross-sectional study was conducted with a sample composed of all the patients who were submitted to liver biopsy during a collective effort carried out in Bahia between July 2007 and November 2009. At the time of the procedure, date on the age and gender of patients and the reason for performing the biopsy were recorded. Data on the degree of fibrosis and the presence of co-morbidities. Following statistical analysis, the frequency of the liver diseases that led to the biopsy procedure was described, and the profile of the patients was stratified into groups according to the most prevalent etiologies. RESULTS: Of the 550 patients evaluated, 55.3% were men and 44.7% women. Mean age was 46.63 ± 11.59 years and there was no statistically significant difference in age between males and females. Of the 550 patients, 72% had hepatitis C and the mean age of these patients was 48.49 ± 10.1 years, significantly higher than the mean age of the patients with hepatitis B (40.41 ± 12.43 years). Furthermore, 70.7% of the patients with hepatitis C were between 41 and 60 years of age. The most frequent fibrosis grade was F2 (44%) and the prevalence of advanced fibrosis was 27.7%. Overall, 85 patients, most of them men, had some degree of iron overload. With respect to the safety of the biopsy procedure, severe complications occurred in only two patients. CONCLUSION: Hepatitis C is the predominant liver disease that demanded liver biopsy. The profile of the patients who benefitted from this collective effort is similar to that of patients in the rest of the country. Moreover, non-Ultrasonography guided liver biopsy is safe and the collective effort to carry out liver biopsies in Bahia was found to be a viable venture.


Assuntos
Biópsia/normas , Hepatopatias/epidemiologia , Fígado/patologia , Adulto , Biópsia/efeitos adversos , Brasil/epidemiologia , Distribuição de Qui-Quadrado , Comorbidade , Estudos Transversais , Feminino , Hepatite B/epidemiologia , Hepatite B/patologia , Hepatite C/epidemiologia , Hepatite C/patologia , Hepatite Autoimune/epidemiologia , Hepatite Autoimune/patologia , Humanos , Hipertensão Portal/epidemiologia , Hipertensão Portal/patologia , Cirrose Hepática/epidemiologia , Cirrose Hepática/patologia , Hepatopatias/diagnóstico , Hepatopatias/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Encaminhamento e Consulta/normas , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
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