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1.
Int J Legal Med ; 137(6): 1875-1885, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37402012

RESUMEN

INTRODUCTION: Due to its peculiar anatomy and physiology, the pericardial fluid is a biological matrix of particular interest in the forensic field. Despite this, the available literature has mainly focused on post-mortem biochemistry and forensic toxicology, while to the best of authors' knowledge post-mortem metabolomics has never been applied. Similarly, estimation of the time since death or post-mortem interval based on pericardial fluids has still rarely been attempted. OBJECTIVES: We applied a metabolomic approach based on 1H nuclear magnetic resonance spectroscopy to ascertain the feasibility of monitoring post-mortem metabolite changes on human pericardial fluids with the aim of building a multivariate regression model for post-mortem interval estimation. METHODS: Pericardial fluid samples were collected in 24 consecutive judicial autopsies, in a time frame ranging from 16 to 170 h after death. The only exclusion criterion was the quantitative and/or qualitative alteration of the sample. Two different extraction protocols were applied for low molecular weight metabolites selection, namely ultrafiltration and liquid-liquid extraction. Our metabolomic approach was based on the use of 1H nuclear magnetic resonance and multivariate statistical data analysis. RESULTS: The pericardial fluid samples treated with the two experimental protocols did not show significant differences in the distribution of the metabolites detected. A post-mortem interval estimation model based on 18 pericardial fluid samples was validated with an independent set of 6 samples, giving a prediction error of 33-34 h depending on the experimental protocol used. By narrowing the window to post-mortem intervals below 100 h, the prediction power of the model was significantly improved with an error of 13-15 h depending on the extraction protocol. Choline, glycine, ethanolamine, and hypoxanthine were the most relevant metabolites in the prediction model. CONCLUSION: The present study, although preliminary, shows that PF samples collected from a real forensic scenario represent a biofluid of interest for post-mortem metabolomics, with particular regard to the estimation of the time since death.

2.
Int J Legal Med ; 137(3): 887-895, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36799966

RESUMEN

INTRODUCTION: The estimation of post-mortem interval (PMI) remains a major challenge in forensic science. Most of the proposed approaches lack the reliability required to meet the rigorous forensic standards. OBJECTIVES: We applied 1H NMR metabolomics to estimate PMI on ovine vitreous humour comparing the results with the actual scientific gold standard, namely vitreous potassium concentrations. METHODS: Vitreous humour samples were collected in a time frame ranging from 6 to 86 h after death. Experiments were performed by using 1H NMR metabolomics and ion capillary analysis. Data were submitted to multivariate statistical data analysis. RESULTS: A multivariate calibration model was built to estimate PMI based on 47 vitreous humour samples. The model was validated with an independent test set of 24 samples, obtaining a prediction error on the entire range of 6.9 h for PMI < 24 h, 7.4 h for PMI between 24 and 48 h, and 10.3 h for PMI > 48 h. Time-related modifications of the 1H NMR vitreous metabolomic profile could predict PMI better than potassium up to 48 h after death, whilst a combination of the two is better than the single approach for higher PMI estimation. CONCLUSION: The present study, although in a proof-of-concept animal model, shows that vitreous metabolomics can be a powerful tool to predict PMI providing a more accurate estimation compared to the widely studied approach based on vitreous potassium concentrations.


Asunto(s)
Cambios Post Mortem , Potasio , Ovinos , Animales , Potasio/análisis , Cuerpo Vítreo/química , Reproducibilidad de los Resultados , Metabolómica
3.
Elife ; 112022 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-36583441

RESUMEN

The combined use of multiple omics allows to study complex interrelated biological processes in their entirety. We applied a combination of metabolomics, lipidomics and proteomics to human bones to investigate their combined potential to estimate time elapsed since death (i.e., the postmortem interval [PMI]). This 'ForensOMICS' approach has the potential to improve accuracy and precision of PMI estimation of skeletonized human remains, thereby helping forensic investigators to establish the timeline of events surrounding death. Anterior midshaft tibial bone was collected from four female body donors before their placement at the Forensic Anthropology Research Facility owned by the Forensic Anthropological Center at Texas State (FACTS). Bone samples were again collected at selected PMIs (219-790-834-872days). Liquid chromatography mass spectrometry (LC-MS) was used to obtain untargeted metabolomic, lipidomic, and proteomic profiles from the pre- and post-placement bone samples. The three omics blocks were investigated independently by univariate and multivariate analyses, followed by Data Integration Analysis for Biomarker discovery using Latent variable approaches for Omics studies (DIABLO), to identify the reduced number of markers describing postmortem changes and discriminating the individuals based on their PMI. The resulting model showed that pre-placement metabolome, lipidome and proteome profiles were clearly distinguishable from post-placement ones. Metabolites in the pre-placement samples suggested an extinction of the energetic metabolism and a switch towards another source of fuelling (e.g., structural proteins). We were able to identify certain biomolecules with an excellent potential for PMI estimation, predominantly the biomolecules from the metabolomics block. Our findings suggest that, by targeting a combination of compounds with different postmortem stability, in the future we could be able to estimate both short PMIs, by using metabolites and lipids, and longer PMIs, by using proteins.


Asunto(s)
Lipidómica , Proteómica , Humanos , Femenino , Proteómica/métodos , Metabolómica/métodos , Cambios Post Mortem , Espectrometría de Masas
4.
J Pers Med ; 12(9)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36143182

RESUMEN

BACKGROUND: several blood-based biomarkers have been proposed for predicting vancomycin-associated kidney injury (VIKI). However, no systematic analysis has compared their prognostic value. OBJECTIVE: this systematic review and meta-analysis was designed to investigate the role of blood biomarkers and metabolomic profiling as diagnostic and prognostic predictors in pre-clinical studies of VIKI. METHODS: a systematic search of PubMed was conducted for relevant articles from January 2000 to May 2022. Animal studies that administered vancomycin and studied VIKI were eligible for inclusion. Clinical studies, reviews, and non-English literature were excluded. The primary outcome was to investigate the relationship between the extent of VIKI as measured by blood biomarkers and metabolomic profiling. Risk of bias was assessed with the CAMARADES checklist the SYRCLE's risk of bias tool. Standard meta-analysis methods (random-effects models) were used. RESULTS: there were four studies for the same species, dosage, duration of vancomycin administration and measurement only for serum creatine and blood urea nitrogen in rats. A statistically significant increase was observed between serum creatinine in the vancomycin group compared to controls (pooled p = 0.037; Standardized Mean Difference: 2.93; 95% CI: 0.17 to 5.69; I2 = 92.11%). Serum BUN levels were not significantly different between control and vancomycin groups (pooled p = 0.11; SMD: 3.05; 95% CI: 0.69 to 6.8; I2 = 94.84%). We did not identify experimental studies using metabolomic analyses in animals with VIKI. CONCLUSIONS: a total of four studies in rodents only described outcomes of kidney injury as defined by blood biomarkers. Blood biomarkers represented included serum creatinine and BUN. Novel blood biomarkers have not been explored.

5.
Int J Antimicrob Agents ; 60(1): 106593, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35460851

RESUMEN

BACKGROUND: Polymyxin B treatment is limited by kidney injury. This study sought to identify Polymyxin B-related urinary metabolomic profile modifications for early detection of polymyxin-associated nephrotoxicity. METHODS: Samples were obtained from a previously conducted study. Male Sprague-Dawley rats received dose-fractionated polymyxin B (12 mg/kg/day) once daily (QD), twice daily (BID), and thrice daily (TID) for three days, with urinary biomarkers and kidney histopathology scores determined. Daily urine was analysed for metabolites via 1H nuclear magnetic resonance (NMR). Principal components analyses identified spectral data trends with orthogonal partial least square discriminant analysis applied to classify metabolic differences. Metabolomes were compared across groups (i.e., those receiving QD, BID, TID, and control) using a mixed-effects models. Spearman correlation was performed for injury biomarkers and the metabolome. RESULTS: A total of 25 rats were treated with Polymyxin B, and n = 2 received saline, contributing 77 urinary samples. Pre-dosing samples clustered well, characterised by higher amounts of citrate, 2-oxoglutarate, and hippurate. Day 1 samples showed higher taurine; day 3 samples had higher lactate, acetate and creatine. Taurine was the only metabolite that significantly increased in both BID and TID compared with the QD group. Day 1 taurine correlated with increasing histopathology scores (rho = 0.4167, P = 0.038) and kidney injury molecule-1 (KIM-1) (rho = 0.4052, P = 0.036), whereas KIM-1 on day 1 and day 3 did not reach significance with histopathology (rho = 0.3248, P = 0.11 and rho = 0.3739, P = 0.066). CONCLUSIONS: Polymyxin B causes increased amounts of urinary taurine on day 1, which then normalizes to baseline concentrations. Taurine may provide one of the earlier signals of acute kidney damage caused by polymyxin B.


Asunto(s)
Lesión Renal Aguda , Polimixina B , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/patología , Animales , Biomarcadores/metabolismo , Riñón , Masculino , Metabolómica , Polimixina B/efectos adversos , Ratas , Ratas Sprague-Dawley , Taurina/metabolismo , Taurina/farmacología
7.
Int J Legal Med ; 136(2): 569-575, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35018499

RESUMEN

A case report suspicious for a Sudden Infant Death Syndrome is here described. Pathological findings were consistent with an acute respiratory failure while toxicological analysis revealed an elevated blood methadone concentration. Death was then ascribed to an acute methadone intoxication. In addition to the routinary approach, the urinary sample collected at autopsy was investigated with a 1H NMR metabolomic approach and the identified metabolomic profile was challenged with the urinary metabolomic profiles previously obtained from 10 newborns who experienced perinatal asphyxia and 16 healthy control newborns. Intriguingly, the urinary profile of the methadone intoxicated infant was very similar to those belonging to the perinatal asphyxia newborns, especially to those belonging to the newborns characterised by the worst outcome. The results offer several hints on a shared metabolic derangement between different mechanisms of asphyxia/hypoxia. To the best of the authors' knowledge, this is the first report of the use of a metabolomic approach in a pathological case, in which metabolomics offers useful additional information regarding the mechanism and the cause of death.


Asunto(s)
Metadona , Muerte Súbita del Lactante , Asfixia , Femenino , Humanos , Lactante , Recién Nacido , Espectroscopía de Resonancia Magnética , Metabolómica/métodos , Embarazo
8.
Chem Res Toxicol ; 34(9): 1946-1947, 2021 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-34283584

RESUMEN

A growing body of evidence suggests that the post-mortem interval exerts a strong effect on the metabolome, independently of the biological matrix or the cause of death. A sound and shared approach in standardization is mandatory.


Asunto(s)
Medicina Legal/normas , Metaboloma/fisiología , Metabolómica/normas , Cambios Post Mortem , Humanos , Estándares de Referencia , Factores de Tiempo
9.
Sci Rep ; 11(1): 10102, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33980966

RESUMEN

The diagnosis of mechanical asphyxia remains one of the most difficult issues in forensic pathology. Asphyxia ultimately results in cardiac arrest (CA) and, as there are no specific markers, the differential diagnosis of primitive CA and CA secondary to asphyxiation relies on circumstantial details and on the pathologist experience, lacking objective evidence. Histological examination is currently considered the gold standard for CA post-mortem diagnosis. Here we present the comparative results of histopathology versus those previously obtained by 1H nuclear magnetic resonance (NMR) metabolomics in a swine model, originally designed for clinical purposes, exposed to two different CA causes, namely ventricular fibrillation and asphyxia. While heart and brain microscopical analysis could identify the damage induced by CA without providing any additional information on the CA cause, metabolomics allowed the identification of clearly different profiles between the two groups and showed major differences between asphyxiated animals with good and poor outcomes. Minute-by-minute plasma sampling allowed to associate these modifications to the pre-arrest asphyxial phase showing a clear correlation to the cellular effect of mechanical asphyxia reproduced in the experiment. The results suggest that metabolomics provides additional evidence beyond that obtained by histology and immunohistochemistry in the differential diagnosis of CA.


Asunto(s)
Asfixia/diagnóstico , Metabolómica/métodos , Espectroscopía de Protones por Resonancia Magnética/métodos , Animales , Asfixia/metabolismo , Asfixia/patología , Modelos Animales de Enfermedad , Femenino , Técnicas Histológicas , Humanos , Porcinos
10.
Diagnostics (Basel) ; 11(3)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670928

RESUMEN

Postmortem analysis of the ocular globe is an important topic for forensic pathology and transplantology. Although crucial elements may be gathered from examining cadaveric eyes, the latter do not routinely undergo in-depth analysis. The paucity of quantitative and objective data that are obtainable using current, invasive necroscopic techniques is the main reason for the limited interest in this highly specialized procedure. The aim of the current study is to describe and to object for the first time the postmortem ocular changes by mean of portable optical coherence tomography for evaluating ocular tissues postmortem. The design involved the postmortem analysis (in situ, and without enucleation) of 12 eyes by portable spectral-domain Optical Coherence Tomography. The scans were performed, in corneal, retinal and angle modality at different intervals: <6 h, 6th, 12th, and 24th hour and after autopsy (25th-72nd hour). The morphological changes in the cornea, sclera, vitreous humor and aqueous humor were easy to explore and objectify in these tissues in first 72 h postmortem. On the other hand, the "in situ" observation of the retina was difficult due to the opacification of the lenses in the first 24 h after death.

11.
Int J Legal Med ; 135(3): 845-852, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33219398

RESUMEN

Estimation of the post-mortem interval (PMI) remains a matter of concern in the forensic scenario. Traditional and novel approaches are not yet able to fully address this issue, which relies on complex biological phenomena triggered by death. For this purpose, eye compartments may be chosen for experimental studies because they are more resistant to post-mortem modifications. Vitreous humour, in particular, has been extensively investigated, with potassium concentration ([K+]) being the marker that is better correlated with PMI estimation. Recently, a 1H nuclear magnetic resonance (NMR) metabolomic approach based on aqueous humour (AH) from an animal model was proposed for PMI estimation, resulting in a robust and validated regression model. Here we studied the variation in [K+] in the same experimental setup. [K+] was determined through capillary ion analysis (CIA) and a regression analysis was performed. Moreover, it was investigated whether the PMI information related to potassium could improve the metabolome predictive power in estimating the PMI. Interestingly, we found that a part of the metabolomic profile is able to explain most of the information carried by potassium, suggesting that the rise in both potassium and metabolite concentrations relies on a similar biological mechanism. In the first 24-h PMI window, the AH metabolomic profile shows greater predictive power than [K+] behaviour, suggesting its potential use as an additional tool for estimating the time since death.


Asunto(s)
Humor Acuoso/química , Metabolómica , Cambios Post Mortem , Potasio/análisis , Animales , Modelos Animales de Enfermedad , Electroforesis Capilar , Espectroscopía de Protones por Resonancia Magnética , Análisis de Regresión , Ovinos
12.
Metabolomics ; 16(11): 118, 2020 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-33159593

RESUMEN

INTRODUCTION: NMR metabolomics is increasingly used in forensics, due to the possibility of investigating both endogenous metabolic profiles and exogenous molecules that may help to describe metabolic patterns and their modifications associated to specific conditions of forensic interest. OBJECTIVES: The aim of this work was to review the recent literature and depict the information provided by NMR metabolomics. Attention has been devoted to the identification of peculiar metabolic signatures and specific ante-mortem and post-mortem profiles or biomarkers related to different conditions of forensic concern, such as the identification of biological traces, the estimation of the time since death, and the exposure to drugs of abuse. RESULTS AND CONCLUSION: The results of the described studies highlight how forensics can benefit from NMR metabolomics by gaining additional information that may help to shed light in several forensic issues that still deserve to be further elucidated.


Asunto(s)
Ciencias Forenses/métodos , Espectroscopía de Resonancia Magnética/métodos , Metabolómica/métodos , Animales , Biomarcadores , Humanos , Metaboloma
13.
Int J Legal Med ; 134(5): 1939-1948, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32676888

RESUMEN

Cadaveric rigidity-also referred to as rigor mortis-is a valuable source of information for estimating the time of death, which is a fundamental and challenging task in forensic sciences. Despite its relevance, assessing the level of cadaveric rigidity still relies on qualitative and often subjective observations, and the development of a more quantitative approach is highly demanded. In this context, ultrasound shear wave elastography (US SWE) appears to be a particularly well-suited technique for grading cadaveric rigidity, as it allows non-invasive quantification of muscle stiffness in terms of Young's modulus (E), which is a widely used parameter in tissue biomechanics. In this pilot study, we measured, for the first time in the literature, changes in the mechanical response of muscular tissues from 0 to 60 h post-mortem (hpm) using SWE, with the aim of investigating its applicability to forensic practice. For this purpose, 26 corpses were included in the study, and the muscle mechanical response was measured at random times in the 0-60 hpm range. Despite the preliminary nature of this study, our data indicate a promising role of SWE in the quantitative determination of cadaveric rigidity, which is still currently based on qualitative and semiquantitative methods. A more in-depth study is required to confirm SWE applicability in this field in order to overcome some of the inherent limitations of the present work, such as the rather low number of cases and the non-systematic approach of the measurements.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Antropología Forense/métodos , Rigor Mortis , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Reproducibilidad de los Resultados
14.
Metabolites ; 10(4)2020 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-32260446

RESUMEN

Brain damage related to perinatal asphyxia is the second cause of neuro-disability worldwide. Its incidence was estimated in 2010 as 8.5 cases per 1000 live births worldwide, with no further recent improvement even in more industrialized countries. If so, hypoxic-ischemic encephalopathy is still an issue of global health concern. It is thought that a consistent number of cases may be avoided, and its sequelae may be preventable by a prompt and efficient physical and therapeutic treatment. The lack of early, reliable, and specific biomarkers has up to now hampered a more effective use of hypothermia, which represents the only validated therapy for this condition. The urge to unravel the biological modifications underlying perinatal asphyxia and hypoxic-ischemic encephalopathy needs new diagnostic and therapeutic tools. Metabolomics for its own features is a powerful approach that may help for the identification of specific metabolic profiles related to the pathological mechanism and foreseeable outcome. The metabolomic profiles of animal and human infants exposed to perinatal asphyxia or developing hypoxic-ischemic encephalopathy have so far been investigated by means of 1H nuclear magnetic resonance spectroscopy and mass spectrometry coupled with gas or liquid chromatography, leading to the identification of promising metabolomic signatures. In this work, an extensive review of the relevant literature was performed.

15.
J Antimicrob Chemother ; 75(5): 1228-1236, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32011685

RESUMEN

BACKGROUND: Vancomycin and piperacillin/tazobactam are reported in clinical studies to increase acute kidney injury (AKI). However, no clinical study has demonstrated synergistic toxicity, only that serum creatinine increases. OBJECTIVES: To clarify the potential for synergistic toxicity between vancomycin, piperacillin/tazobactam and vancomycin + piperacillin/tazobactam treatments by quantifying kidney injury in a translational rat model of AKI and using cell studies. METHODS: (i) Male Sprague-Dawley rats (n = 32) received saline, vancomycin 150 mg/kg/day intravenously, piperacillin/tazobactam 1400 mg/kg/day intraperitoneally or vancomycin + piperacillin/tazobactam for 3 days. Urinary biomarkers and histopathology were analysed. (ii) Cellular injury was assessed in NRK-52E cells using alamarBlue®. RESULTS: Urinary output increased from Day -1 to Day 1 with vancomycin but only after Day 2 for vancomycin + piperacillin/tazobactam-treated rats. Plasma creatinine was elevated from baseline with vancomycin by Day 2 and only by Day 4 for vancomycin + piperacillin/tazobactam. Urinary KIM-1 and clusterin were increased with vancomycin from Day 1 versus controls (P < 0.001) and only on Day 3 with vancomycin + piperacillin/tazobactam (P < 0.001, KIM-1; P < 0.05, clusterin). The histopathology injury score was elevated only in the vancomycin group when compared with piperacillin/tazobactam as a control (P = 0.04) and generally not so with vancomycin + piperacillin/tazobactam. In NRK-52E cells, vancomycin induced cell death with high doses (IC50 48.76 mg/mL) but piperacillin/tazobactam did not, and vancomycin + piperacillin/tazobactam was similar to vancomycin. CONCLUSIONS: All groups treated with vancomycin demonstrated AKI; however, vancomycin + piperacillin/tazobactam was not worse than vancomycin. Histopathology suggested that piperacillin/tazobactam did not worsen vancomycin-induced AKI and may even be protective.


Asunto(s)
Lesión Renal Aguda , Vancomicina , Lesión Renal Aguda/inducido químicamente , Animales , Antibacterianos/toxicidad , Quimioterapia Combinada , Masculino , Ácido Penicilánico/toxicidad , Piperacilina/toxicidad , Combinación Piperacilina y Tazobactam/toxicidad , Ratas , Ratas Sprague-Dawley , Estudios Retrospectivos , Vancomicina/toxicidad
16.
Biomarkers ; 24(8): 727-734, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31613149

RESUMEN

Objectives: Arsenic is a toxic metal ubiquitous in the environment and in daily life items. Long-term arsenic exposure is associated with severe adverse health effects involving various target organs. It would be useful to investigate the existence of metabolic alterations associated with lifestyle and/or with the environment. For this purpose, we studied the correlation between urinary arsenic levels and urinary proton nuclear magnetic resonance spectroscopy (1H NMR) metabolomics profiles in a non-occupationally nor environmentally arsenic exposed general population.Methods: Urine samples were collected from 86 healthy subjects. Total and non-alimentary urinary arsenic (U-naAs) levels, namely the sum of arsenite, arsenate, monomethylarsonate and dimethylarsinate, were measured and 1H NMR analysis was performed. Orthogonal Projection to Latent Structures was applied to explore the correlation between the metabolomics profiles and U-naAs levels.Results: Despite the extremely low U-naAs levels (mean value = 6.13 ± 3.17 µg/g creatinine) of our studied population a urinary metabolomics profile related to arsenic was identified.Conclusion: The identified profile could represent a fingerprint of early arsenic biological effect and could be used in further studies as an indicator of susceptibility, also in subjects exposed to a low arsenic dose, with implications in occupational health, toxicology, and public health.


Asunto(s)
Arsénico/orina , Metabolómica/métodos , Adulto , Exposición a Riesgos Ambientales/análisis , Exposición a Riesgos Ambientales/normas , Voluntarios Sanos , Humanos , Italia , Metabolómica/normas , Espectroscopía de Protones por Resonancia Magnética
17.
Metabolomics ; 15(5): 76, 2019 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-31069551

RESUMEN

INTRODUCTION: The estimation of the time since death, or post-mortem interval (PMI), still remains a main conundrum in forensic science. Several approaches have been so far proposed from either a qualitative or a quantitative point of view, but they still lack reliability and robustness. Recently, metabolomics has shown to be a potential tool to investigate the time-related post-mortem metabolite modifications in animal models. OBJECTIVES: Here we propose, for the first time, the use of a 1H NMR metabolomic approach for the estimation of PMI from aqueous humour (AH) in an ovine model. METHODS: AH samples were collected at different times after death (from 118 to 1429 min). 1H NMR experiments were performed and spectral data analysed by multivariate statistical tools. RESULTS: A multivariate calibration model was built to estimate PMI on the basis of the metabolite content of the samples. The model was validated with an independent test set, obtaining a prediction error of 59 min for PMI < 500 min, 104 min for PMI from 500 to 1000 min, and 118 min for PMI > 1000 min. Moreover, the metabolomic approach suggested a picture of the mechanisms underlying the post-mortem biological modifications, highlighting the role played by taurine, choline, and succinate. CONCLUSION: The time-related modifications of the 1H NMR AH metabolomic profile seem to be encouraging in addressing the issue of a reproducible and robust model to be employed for the estimation of the time since death.


Asunto(s)
Humor Acuoso/metabolismo , Modelos Animales de Enfermedad , Metabolómica , Cambios Post Mortem , Animales , Femenino , Espectroscopía de Protones por Resonancia Magnética , Ovinos , Factores de Tiempo
18.
Metabolites ; 9(3)2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30884746

RESUMEN

Metabolomics is the systematic study of the small-molecule profiles of biological samples produced by specific cellular processes. The high-throughput technologies used in metabolomic investigations generate datasets where variables are strongly correlated and redundancy is present in the data. Discovering the hidden information is a challenge, and suitable approaches for data analysis must be employed. Projection to latent structures regression (PLS) has successfully solved a large number of problems, from multivariate calibration to classification, becoming a basic tool of metabolomics. PLS2 is the most used implementation of PLS. Despite its success, PLS2 showed some limitations when the so called 'structured noise' affects the data. Suitable methods have been recently introduced to patch up these limitations. In this study, a comprehensive and up-to-date presentation of PLS2 focused on metabolomics is provided. After a brief discussion of the mathematical framework of PLS2, the post-transformation procedure is introduced as a basic tool for model interpretation. Orthogonally-constrained PLS2 is presented as strategy to include constraints in the model according to the experimental design. Two experimental datasets are investigated to show how PLS2 and its improvements work in practice.

19.
PLoS One ; 13(4): e0194267, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29668681

RESUMEN

Perinatal asphyxia is an event affecting around four million newborns worldwide. The 0.5 to 2 per 1000 of full term asphyxiated newborns suffer from hypoxic-ischemic encephalopathy (HIE), which is a frequent cause of death or severe disability and, as consequence, the most common birth injury claim for obstetrics, gynaecologists, and paediatricians. Perinatal asphyxia results from a compromised gas exchange that leads to hypoxemia, hypercapnia, and metabolic acidosis. In this work, we applied a metabolomics approach to investigate the metabolic profiles of urine samples collected from full term asphyxiated newborns with HIE undergoing therapeutic hypothermia (TH), with the aim of identifying a pattern of metabolites associated with HIE and to follow their modifications over time. Urine samples were collected from 10 HIE newborns at birth, during hypothermia (48 hours), at the end of the therapeutic treatment (72 hours), at 1 month of life, and compared with a matched control population of 16 healthy full term newborns. The metabolic profiles were investigated by 1H NMR spectroscopy coupled with multivariate statistical methods such as principal component analysis and orthogonal partial least square discriminant analysis. Multivariate analysis indicated significant differences between the urine samples of HIE and healthy newborns at birth. The altered metabolic patterns, mainly originated from the depletion of cellular energy and homeostasis, seem to constitute a characteristic of perinatal asphyxia. The HIE urine metabolome changes over time reflected either the effects of TH and the physiological growth of the newborns. Of interest, the urine metabolic profiles of the HIE non-surviving babies, characterized by the increased excretion of lactate, resulted significantly different from the rest of HIE population.


Asunto(s)
Hipotermia Inducida , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/orina , Metaboloma , Metabolómica , Espectroscopía de Protones por Resonancia Magnética , Asfixia Neonatal , Estudios de Casos y Controles , Femenino , Humanos , Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/mortalidad , Recién Nacido , Estudios Longitudinales , Masculino , Metabolómica/métodos
20.
Exp Eye Res ; 169: 20-27, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29360448

RESUMEN

The aim of this work was to describe, for the first time, the morphological modifications, in a three-dimensional mode, of the central cornea at different intervals since death. The study design involved the analysis of 30 eyes (15 heads) of female, adult sheep (>2 years) sacrificed at a local slaughterhouse. The eyes, after animal decapitation, were examined in situ, without enucleation. Ocular globes were stored at well-known temperature (within a range of 12-22 °C) and humidity (within a range of 50-60%). The instrumental analysis was executed using a portable spectral-domain OCT (SD-OCT) system (iVue SD-OCT, Optovue Inc, Fremont, CA) calibrated to the corneal mode. OCT imaging was performed at different time-points since death. Pachymetric map, morphological and ultrastructural analysis (epithelium, stroma, and endothelium), were performed for each time-point. After an initial thinning of tissues and an enhancement of epithelial reflectivity, stromal thickness increased from the 2nd up to the 6th hour. Subsequently, a new trend incorneal thinning was observed in association with the appearance ofone or more demarcation lines between the anterior andposterior stroma. After the 12th hour, a recurrence of corneal swelling was detected in association with thedelamination of stromal tissue. Since the 24th hour, the epithelium disappeared in 50% of cases and the anterior chamberdepth progressively decreased. At the 48th hour, various ocular structures showed the onset of putrefaction processes, such as theappearance of hyper-reflective dots in anterior chamber, iridocorneal contact, and the massive vacuolization of theposterior stroma until the total delamination. The portable OCT system is a useful approach for in situ postmortem corneal examination, and it may be potentially applied for the selection of donor cornea in transplantology and for the determination of post-mortem intervals in forensic medicine.


Asunto(s)
Córnea/diagnóstico por imagen , Modelos Animales , Cambios Post Mortem , Tomografía de Coherencia Óptica/métodos , Animales , Córnea/ultraestructura , Paquimetría Corneal , Sustancia Propia/diagnóstico por imagen , Sustancia Propia/ultraestructura , Endotelio Corneal/diagnóstico por imagen , Endotelio Corneal/ultraestructura , Epitelio Corneal/diagnóstico por imagen , Epitelio Corneal/ultraestructura , Femenino , Imagenología Tridimensional , Ovinos , Factores de Tiempo
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