Aplicación de modelos metabolómicos para la identificación de EPOC en poblaciones expuestas a humo de leña en una comunidad indígena de México / Application of metabolomic models for the identificaron of coPD in populations exposed to wood smoke in an indigenous community in Mexico

Resumen Propósito: Para la evaluación metabólica de la fisiopatología pulmonar se utiliza principalmente el aliento exhalado, el cual ha tomado una gran relevancia como método de diagnóstico no invasivo, de bajo costo, rápido y seguro. El objetivo del presente estudio fue aplicar modelos metabolómicos para la identificación de la Enfermedad Pulmonar Obstructiva Crónica (EPOC) en población vulnerable expuesta a la quema de biomasa en una comunidad indígena de México. Métodos: El estudio se conformó por 142 participantes, 44 pacientes con EPOC asociado a la quema de biomasa, 60 controles y 38 población indígena expuesta a la quema de biomasa (PIE). Las muestras de aliento exhalado se analizaron mediante una nariz electrónica (HERACLES II, Alpha MOS). Con los datos obtenidos se realizó un Análisis Canónico de Coordenadas principales (CAP), que fue utilizado para la predicción de EPOC de la PIE y se determinó la concentración de 1-hidroxipireno (1-OHP) en muestras de orina. Resultados: Se logró identificar un total 59 COVs en las muestras de aliento exhalado de los grupos de estudio, los cuales se utilizaron para establecer un modelo de discriminación entre la huella química del grupo de pacientes con EPOC y el grupo control. El modelo CAP indicó una separación entre las huellas químicas de los pacientes con EPOC y sujetos sanos, con una correcta predicción de 91,34%, con una sensibilidad y especificidad de 93,2 y 96,7% respectivamente. Se encontraron 10 participantes de la PIE con patrón obstructivo y una alta concentración de 1-OHP, determinando que existe una concentración del 1,31 ± 0,67gg/mol de creatinina. Esta concentración se encuentra más de 5 veces arriba de los valores de referencia establecidos en el 2001, que es de 0,24 gg/mol de creatinina. Al comparar los resultados de la huella química de la PIE se posicionó en el grupo de EPOC. Conclusión: Se logró obtener un diagnóstico oportuno en población vulnerable mediante el uso de la metabolómica y se demostró la exposición y los efectos pulmonares en población indígena de San Luis Potosí.

Abstract Purpose: to evaluate metabolic disorders of the pathophysiology of the lung, the exhaled breath is mainly used, this has become highly relevant as a non-invasive, low-cost, fast and safe diagnostic method. The objective of this study is to apply metabolomic models for the identification of Chronic Obstructive Pulmonary Disease (COPD) in a vulnerable population exposed to biomass burning in an indigenous community in Mexico. Methods: The study consisted of 142 participants, 44 patients with COPD associated with biomass burning, 60 controls and 38 indigenous population exposed to biomass burning (PIE). Exhaled breath samples were analyzed using an electronic nose (HERACLES II, Alpha MOS). With the data obtained, a Canonical Analy-sis of Principal Coordinates (CAP) was performed, which was used for the prediction of COPD of IEP and the concentration of 1-hydroxypyrene (1-OHP) in urine samples was determined. Results: A total of 59 VOCs were identified in the exhaled breath samples of the study groups, which were used to establish a discrimination model between the chemical fingerprint of the COPD patient group and the control group. The CAP model indicated a separation between the chemical fingerprints of COPD patients and healthy subjects, with a correct prediction of 91,34%, with a sensitivity and specificity of 93,2 and 96,7%, respectively. 10 IEP participants with an obstructive pattern and a high concentration of 1-OHP were found, determining that there is a concentration of 1,31 ± 0,67gg/mol of creatinine. This concentration is more than 5 times above the reference values established in 2001, which is 0,24 -jg/mol of creatinine. When comparing the results of the Chemical fingerprint of the PIE, it was positioned in the COPD group. Conclusion: It was possible to obtain an opportune diagnosis in a vulnerable population using metabolomics and exposure and pulmonary effects were demonstrated in the indigenous population of San Luis Potosí.

Identification of profiles of volatile organic compounds in exhaled breath by means of an electronic nose as a proposal for a screening method for breast cancer: a case-control study.

The objective of the present study was to identify volatile prints from exhaled breath, termed breath-print, from breast cancer (BC) patients and healthy women by means of an electronic nose and to evaluate its potential use as a screening method. A cross-sectional study was performed on 443 exhaled breath samples from women, of whom 262 had been diagnosed with BC by biopsy and 181 were healthy women (control group). Breath-print analysis was performed utilizing the Cyranose 320 electronic nose. Group data were evaluated by principal component analysis (PCA), canonical discriminant analysis (CDA), and support vector machine (SVM), and the test's diagnostic power was evaluated by means of receiver operating characteristic (ROC) curves. The results obtained using the model generated from the CDA, which best describes the behavior of the assessed groups, indicated that the breath-print of BC patients was different from that of healthy women and that they presented with a variability of up to 98.8% and a correct classification of 98%. The sensitivity, specificity, negative predictive value, and positive predictive value reached 100% according to the ROC curve. The present study demonstrates the capability of the electronic nose to separate between healthy subjects and BC patients. This research could have a beneficial impact on clinical practice as we consider that this test could probably be used at the first point before the application of established gold tests (mammography, ultrasound, and biopsy) and substantially improve screening tests in the general population.