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2.
Math Biosci Eng ; 20(5): 9159-9178, 2023 03 14.
Article in English | MEDLINE | ID: mdl-37161238

ABSTRACT

About 6.5 million people are infected with Chagas disease (CD) globally, and WHO estimates that $ > million people worldwide suffer from ChHD. Sudden cardiac death (SCD) represents one of the leading causes of death worldwide and affects approximately 65% of ChHD patients at a rate of 24 per 1000 patient-years, much greater than the SCD rate in the general population. Its occurrence in the specific context of ChHD needs to be better exploited. This paper provides the first evidence supporting the use of machine learning (ML) methods within non-invasive tests: patients' clinical data and cardiac restitution metrics (CRM) features extracted from ECG-Holter recordings as an adjunct in the SCD risk assessment in ChHD. The feature selection (FS) flows evaluated 5 different groups of attributes formed from patients' clinical and physiological data to identify relevant attributes among 57 features reported by 315 patients at HUCFF-UFRJ. The FS flow with FS techniques (variance, ANOVA, and recursive feature elimination) and Naive Bayes (NB) model achieved the best classification performance with 90.63% recall (sensitivity) and 80.55% AUC. The initial feature set is reduced to a subset of 13 features (4 Classification; 1 Treatment; 1 CRM; and 7 Heart Tests). The proposed method represents an intelligent diagnostic support system that predicts the high risk of SCD in ChHD patients and highlights the clinical and CRM data that most strongly impact the final outcome.


Subject(s)
Death, Sudden, Cardiac , Machine Learning , Humans , Bayes Theorem , Death, Sudden, Cardiac/epidemiology , Risk Assessment , Electrocardiography
3.
Sci Rep ; 12(1): 10112, 2022 06 16.
Article in English | MEDLINE | ID: mdl-35710933

ABSTRACT

Very long-chain (> C24) polyunsaturated fatty acids (VLC-PUFA) play an important role in the development of nervous system, retinal function and reproductive processes in vertebrates. Their presence in very small amounts in specific lipid classes, the lack of reference standards and their late elution in chromatographic analyses render their identification and, most important, their quantification, still a challenge. Consequently, a sensitive and feasible analytical methodology is needed. In this work, we have studied the effect of chain length, as well as the number and position of unsaturations (or double bonds) on the response of GC-APCI-(Q)TOF MS, to establish an analytical method for VLC-PUFA quantification. The developed methodology allows the quantification of these compounds down to 2.5 × 10-3 pmol/mg lipid. The reduction of VLC-PUFA levels in lipid fractions of the organs from the herein sampled farmed fish suggesting a yet undetected effect on these compounds of high vegetable oil aquafeed formulations, that currently dominate the market.


Subject(s)
Sea Bream , Animals , Brain , Fatty Acids , Fatty Acids, Unsaturated/analysis , Gonads/chemistry , Sea Bream/physiology
4.
Anal Bioanal Chem ; 413(4): 1039-1046, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33210175

ABSTRACT

The characterization of very long-chain (>C24) polyunsaturated fatty acids (VLC-PUFAs), which are essential in the vision, neural function, and reproduction of vertebrates, is challenging because of the lack of reference standards and their very low concentrations in certain lipid classes. In this research, we have developed a new methodology for VLC-PUFA identification based on gas chromatography coupled to quadrupole/time-of-flight mass spectrometry with an atmospheric pressure chemical ionization source (GC-APCI-QTOF MS). The mass accuracy attainable with the innovative QTOF instrument, together with the soft ionization of the APCI source, provides valuable information on the intact molecule, traditionally lost with electron ionization sources due to the extensive fragmentation suffered. We have identified, for the first time, VLC-PUFAs with chains up to 44 carbons in eyes, brain, and gonads of gilthead sea bream, a commercially important fish in the Mediterranean. The added value of ion mobility-mass spectrometry (IMS), recently developed in combination with GC-QTOF MS, and the contribution of the collisional cross section (CCS) parameter in the characterization of novel VLC-PUFAs (for which reference standards are not available) have been also evaluated. The methodology developed has allowed assessing qualitative differences between farmed and wild fish, and opens new perspectives in a still scarcely known field of research.


Subject(s)
Fatty Acids, Unsaturated/analysis , Sea Bream/metabolism , Animals , Atmospheric Pressure , Fatty Acids, Unsaturated/metabolism , Gas Chromatography-Mass Spectrometry/methods , Ion Mobility Spectrometry
5.
Food Res Int ; 137: 109698, 2020 11.
Article in English | MEDLINE | ID: mdl-33233272

ABSTRACT

With the increase of the demand of low flavouring smoked seafood products, there is a need of methodologies able to distinguish between different seafood treatments, as not all of them are allowed in all markers. Following this objective, in the present work an untargeted volatolomics approach was applied to identify volatile markers that demonstrate that Cold smoked products can be distinguished from Tasteless smoke neither Carbon monoxide treated seafood, which are prohibited in the European Union. The use of dynamic headspace for the volatile extraction followed by thermal desorption in combination with Gas Chromatography (GC) coupled to single quadrupole Mass Spectrometry (MS) has been employed for the determination of volatile composition of smoked fish. Data processing consisted on the use of PARADISe software, applied for GC/MS data treatment, followed by the multivariate analysis with PLS_Toolbox (MATLAB), and finally the creation and validation of statistical classification model. All 107 variables obtained allowed the construction of a model reaching the correct classification of 97% of the blind samples, while a simplified model with only 11 variables correctly classified up to 93% of the blind samples. These 11 compounds were elucidated to develop subsequent target volatolomics approaches, if needed. Ordered according to the importance in the classification model, the elucidated compounds were: 3-methyl-cyclopentanone, ethylbenzene, 2-methyl-2-cyclopenten-1-one, 2-methyl-benzofuran, furfuryl alcohol, 2-acetylfuran, acetophenone, guaiacol, 1-hydroxy-2-butanone, 4-vinylguaicol and acetoin. The results demonstrated the great potential of untargeted volatolomics for smoked seafood treatments classification.


Subject(s)
Volatile Organic Compounds , Animals , Gas Chromatography-Mass Spectrometry , Mass Spectrometry , Seafood/analysis , Smoke , Volatile Organic Compounds/analysis
6.
Pharmaceutics ; 12(5)2020 May 25.
Article in English | MEDLINE | ID: mdl-32466339

ABSTRACT

Gene therapy is a therapeutic process consisting of the transport of genetic material into cells. The design and preparation of novel carriers to transport DNA is an important research line in the medical field. Hybrid compounds such as metallo-liposomes, containing a mixture of lipids, were prepared and characterized. Cationic metal lipids derived from the [Ru(bpy)3]2+ complex, RuC11C11 or RuC19C19, both with different hydrophobic/lipophilic ratios, were mixed with the phospholipid DOPE. A relation between the size and the molar fraction α was found and a multidisciplinary study about the interaction between the metallo-liposomes and DNA was performed. The metallo-liposomes/DNA association was quantified and a relationship between Kapp and α was obtained. Techniques such as AFM, SEM, zeta potential, dynamic light scattering and agarose gel electrophoresis demonstrated the formation of lipoplexes and showed the structure of the liposomes. L/D values corresponding to the polynucleotide's condensation were estimated. In vitro assays proved the low cell toxicity of the metallo-liposomes, lower for normal cells than for cancer cell lines, and a good internalization into cells. The latter as well as the transfection measurements carried out with plasmid DNA pEGFP-C1 have demonstrated a good availability of the Ru(II)-based liposomes for being used as non-toxic nanovectors in gene therapy.

7.
Environ Sci Technol ; 52(4): 2331-2338, 2018 02 20.
Article in English | MEDLINE | ID: mdl-29376341

ABSTRACT

The occurrence of 14 organophosphorus flame retardants and plasticizers (PFRs) was investigated in 165 composite food samples purchased from the Belgian market and divided into 14 food categories, including fish, crustaceans, mussels, meat, milk, cheese, dessert, food for infants, fats and oils, grains, eggs, potatoes and derived products, other food (stocks), and vegetables. Seven PFRs [namely, tri-n-butyl phosphate (TnBP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPHP), 2-ethylhexyldiphenyl phosphate (EHDPHP), and tris(2-ethylhexyl) phosphate (TEHP)] were detected at concentrations above quantification limits. Fats and oils were the most contaminated category, with a total PFR concentration of 84.4 ng/g of wet weight (ww), followed by grains (36.9 ng/g of ww) and cheese (20.1 ng/g of ww). Our results support the hypothesis that PFR contamination may occur during industrial processing and manipulation of food products (e.g., packaging, canning, drying, etc.). Considering the daily average intake of food for the modal adult Belgian (15-64 years of age), the dietary exposure to sum PFRs was estimated to be ≤7500 ± 1550 ng/day [103 ± 21 ng/kg of body weight (bw)/day]. For individual PFRs, TPHP contributed on average 3400 ng/day (46.6 ng/kg of bw/day), TCIPP 1350 ng/day (18.5 ng/kg of bw/day), and EHDPHP 1090 ng/day (15 ng/kg of bw/day), values that were lower than their corresponding health-based reference doses. The mean dietary exposure mainly originated from grains (39%), followed by fats and oils (21%) and dairy products (20%). No significant differences between the intakes of adult men and women were observed.


Subject(s)
Flame Retardants , Adolescent , Adult , Aged , Animals , Belgium , Dietary Exposure , Female , Humans , Male , Middle Aged , Organophosphates , Organophosphorus Compounds , Plasticizers , Young Adult
8.
Anal Bioanal Chem ; 409(19): 4507-4515, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28593372

ABSTRACT

A sensitive method for the simultaneous quantification of dechloranes, polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NBFRs) has been developed for gas chromatography (GC) coupled to tandem mass spectrometry operating in electron capture negative ionization (ECNI) mode. The major advance has been achieved by combining selected ion monitoring (SIM) and multiple reaction monitoring (MRM) modes in well-defined time windows, to determine dechloranes, PBDEs and NBFRs at picogram per gram level in one single analysis in complex matrix biological samples. From the chromatographic point of view, efforts were devoted to study several injection modes using multimode inlet (MMI) in order to obtain low instrumental detection limits, necessary for trace compounds such as Dechlorane Plus (DP) isomers. Method performance was also evaluated: calibration curves were linear from 20 fg µL-1 to 100 pg µL-1 for the studied compounds, with method detection limits at levels of 50 fg g-1 for DPs. Repeatability and reproducibility, expressed as relative standard deviation, were better than 5% even in solvent vent mode for the injection of standards. The application to a wide range of complex samples (including food, human and animal serum samples) indicated a sensitive and reliable way to quantify at the picogram per gram level 4 halogenated norbornenes (HNs), Dechlorane Plus (anti-DP and syn-DP) and 2 of their homologues (Dechlorane-602 and Dechlorane-603), 11 PBDE congeners (no. 28, 47, 49, 66, 85, 99, 100, 153, 154, 183 and 209) and 5 novel BFRs, i.e. decabromodiphenyl ethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), hexabromobenzene (HBB), 2,3,4,5-tetrabromo-ethylhexyl-benzoate (TBB) and tetrabromophthalate (TBPH). Graphical Abstract GC-ECNI-MS/MS chromatograms showing the most sensitive transition for DPs when injecting 2 µL of a 16 fg/µL standard solution of s-DP and a-DP at three different source temperatures.


Subject(s)
Flame Retardants/analysis , Food Analysis , Halogenated Diphenyl Ethers/analysis , Hydrocarbons, Chlorinated/analysis , Animals , Halogenated Diphenyl Ethers/blood , Humans , Hydrocarbons, Chlorinated/blood
9.
Heart ; 102(5): 376-82, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26802099

ABSTRACT

OBJECTIVE: To assess the usefulness of hand-held cardiac ultrasound (HCU) performed by family doctors (FDs) in primary care, with web-based remote expert support interpretation, in a cohort of patient with symptoms or physical examination signs suggestive of cardiovascular disease. METHODS: This prospective observational study included 1312 consecutive patients, in three remote primary care areas, with symptoms or physical examination signs suggestive of cardiovascular disease. In 859 patients (group A), FDs had indicated conventional echocardiography (CE), and in 453 (Group B) the study was performed to complement the physical examination. HCU was carried out by 14 FDs after a short training period. The scans and preliminary FD reports were uploaded on a web-based program for remote expert support interpretation in <24 h. RESULTS: Experts considered HCU to be inconclusive in 116 (8.8%) patients. FD and expert agreement on diagnosis was moderate (K=0.40-0.70) except in mitral stenosis (K=0.29) and in left atrial dilation (K=0.38). Diagnostic agreement between expert interpretation and CE was good (K=0.66-0.85) except in mitral stenosis (K=0.43). After remote expert interpretation, conventional echocardiograms were finally requested by FDs in only 276 (32.1%) patients, and discharges increased by 10.2%. Furthermore, significant heart diseases were diagnosed in 32 (7%) patients of group B. CONCLUSIONS: HCU performed at the point of care by FDs with remote expert support interpretation using a web-based system is feasible, rapid and useful for detecting significant echocardiographic abnormalities and reducing the number of unnecessary echocardiographic studies.


Subject(s)
Diagnosis, Computer-Assisted/methods , Echocardiography, Doppler, Color/methods , Heart Diseases/diagnostic imaging , Physicians, Family , Point-of-Care Testing , Primary Health Care , Remote Consultation/methods , Rural Health Services , Adolescent , Adult , Aged , Aged, 80 and over , Echocardiography, Doppler, Color/instrumentation , Education, Medical, Continuing , Equipment Design , Feasibility Studies , Female , Heart Diseases/therapy , Humans , Inservice Training , Internet , Male , Middle Aged , Observer Variation , Physicians, Family/education , Point-of-Care Systems , Predictive Value of Tests , Prognosis , Prospective Studies , Reproducibility of Results , Spain , Transducers , Unnecessary Procedures , Young Adult
10.
Front Plant Sci ; 7: 1954, 2016.
Article in English | MEDLINE | ID: mdl-28119698

ABSTRACT

Drought and heat stresses are two of the most frequent environmental factors that take place simultaneously in the field constraining global crop productivity. Metabolism reconfiguration is often behind the adaptation of plants to adverse environmental conditions. Carrizo citrange and Cleopatra mandarin, two citrus genotypes with contrasting ability to tolerate combined heat and drought conditions, showed different metabolite patterns. Increased levels of phenylpropanoid metabolites were observed in Cleopatra in response to stress, including scopolin, a metabolite involved in defense mechanisms. Tolerant Carrizo accumulated sinapic acid and sinapoyl aldehyde, direct precursors of lignins. Finally, Cleopatra showed an accumulation of flavonols and glycosylated and polymethoxylated flavones such as tangeritin. The activation of flavonoid biosynthesis in Cleopatra could be aimed to mitigate the higher oxidative damage observed in this genotype. In general, limonoids were more severely altered in Cleopatra than in Carrizo in response to stress imposition. To conclude, all metabolite changes observed in Cleopatra suggest the activation of energy metabolism along with metabolic pathways leading to the accumulation of photoprotective and antioxidant secondary metabolites, oriented to mitigate the damaging effects of stress. Conversely, the higher ability of Carrizo to retain a high photosynthetic activity and to cope with oxidative stress allowed the maintenance of the metabolic activity and prevented the accumulation of antioxidant metabolites.

11.
Anal Bioanal Chem ; 408(2): 449-59, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26554601

ABSTRACT

A fast method for the screening and quantification of hexabromocyclododecane (sum of all isomers) by gas chromatography using a triple quadrupole mass spectrometer with atmospheric pressure chemical ionization (GC-APCI-QqQ) is proposed. This novel procedure makes use of the soft atmospheric pressure chemical ionization source, which results in less fragmentation of the analyte than by conventional electron impact (EI) and chemical ionization (CI) sources, favoring the formation of the [M - Br](+) ion and, thus, enhancing sensitivity and selectivity. Detection was based on the consecutive loses of HBr from the [M - Br](+) ion to form the specific [M - H5Br6](+) and [M - H4Br5](+) ions, which were selected as quantitation (Q) and qualification (q) transitions, respectively. Parameters affecting ionization and MS/MS detection were studied. Method performance was also evaluated; calibration curves were found linear from 1 pg/µL to 100 pg/µL for the total HBCD concentration; instrumental detection limit was estimated to be 0.10 pg/µL; repeatability and reproducibility, expressed as relative standard deviation, were better than 7% in both cases. The application to different real samples [polyurethane foam disks (PUFs), food, and marine samples] pointed out a rapid way to identify and allow quantification of this compound together with a number of polybrominated diphenyl ethers (BDE congeners 28, 47, 66, 85, 99, 100, 153, 154, 183, 184, 191, 196, 197, and 209) and two other novel brominated flame retardants [i.e., decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE)] because of their presence in the same fraction when performing the usual sample treatment.


Subject(s)
Flame Retardants/analysis , Gas Chromatography-Mass Spectrometry/methods , Hydrocarbons, Brominated/chemistry , Animals , Aquatic Organisms/chemistry , Decapodiformes , Dolphins , Environmental Pollutants/chemistry , Fishes , Humans , Milk, Human/chemistry , Molecular Structure , Tandem Mass Spectrometry/methods
12.
Food Chem ; 190: 689-700, 2016 Jan 01.
Article in English | MEDLINE | ID: mdl-26213027

ABSTRACT

A dynamic headspace purge-and-trap (DHS-P&T) methodology for the determination and quantification of 61 volatile compounds responsible for muskmelon and watermelon aroma has been developed and validated. The methodology is based on the application of purge-and-trap extraction followed by gas chromatography coupled to (ion trap) mass spectrometry detection. For this purpose two different P&T sorbent cartridges have been evaluated. The influence of different extraction factors (sample weight, extraction time, and purge flow) on extraction efficiency has been studied and optimised using response surface methodology. Precision, expressed as repeatability, has been evaluated by analysing six replicates of real samples, showing relative standard deviations between 3% and 27%. Linearity has been studied in the range of 10-6130 ng mL(-1) depending on the compound response, showing coefficients of correlation between 0.995 and 0.999. Detection limits ranged between 0.1 and 274 ng g(-1). The methodology developed is well suited for analysis of large numbers of muskmelon and watermelon samples in plant breeding programs.


Subject(s)
Citrullus/chemistry , Fruit/chemistry , Gas Chromatography-Mass Spectrometry/methods , Odorants/analysis , Volatile Organic Compounds/chemistry
13.
Anal Chem ; 87(19): 9892-9, 2015 Oct 06.
Article in English | MEDLINE | ID: mdl-26354040

ABSTRACT

The analysis of brominated flame retardants (BFRs) commonly relies on the use of gas chromatography coupled to mass spectrometry (GC-MS) operating in electron ionization (EI) and electron capture negative ionization (ECNI) modes using quadrupole, triple quadrupole, ion trap, and magnetic sector analyzers. However, these brominated contaminants are examples of compounds for which a soft and robust ionization technique might be favorable since they show high fragmentation in EI and low specificity in ECNI. In addition, the low limits of quantification (0.01 ng/g) required by European Commission Recommendation 2014/118/EU on the monitoring of traces of BFRs in food put stress on the use of highly sensitive techniques/methods. In this work, a new approach for the extremely sensitive determination of BFRs taking profit of the potential of atmospheric pressure chemical ionization (APCI) combined with GC and triple quadrupole (QqQ) mass analyzer is proposed. The objective was to explore the potential of this approach for the BFRs determination in samples at pg/g levels, taking marine samples and a cream sample as a model. Ionization and fragmentation behavior of 14 PBDEs (congeners 28, 47, 66, 85, 99, 100, 153, 154, 183, 184, 191, 196, 197, and 209) and two novel BFRs, decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), in the GC-APCI-MS system has been investigated. The formation of highly abundant (quasi) molecular ion was the main advantage observed in relation to EI. Thus, a notable improvement in sensitivity and specificity was observed when using it as precursor ion in tandem MS. The improved detectability (LODs < 10 fg) achieved when using APCI compared to EI has been demonstrated, which is especially relevant for highly brominated congeners. Analysis of samples from an intercomparison exercise and samples from the marine field showed the potential of this approach for the reliable identification and quantification at very low concentration levels.


Subject(s)
Bromobenzenes/analysis , Environmental Monitoring/methods , Flame Retardants/analysis , Gas Chromatography-Mass Spectrometry/methods , Halogenated Diphenyl Ethers/analysis , Animals , Environmental Monitoring/instrumentation , Equipment Design , Fishes/metabolism , Gas Chromatography-Mass Spectrometry/instrumentation , Limit of Detection , Reproducibility of Results , Tandem Mass Spectrometry/instrumentation , Tandem Mass Spectrometry/methods
14.
Bogotá; s.n; oct. 1991. 83 p. ilus, tab, graf.
Thesis in Spanish | LILACS | ID: lil-190065

ABSTRACT

Se revisaron 17 casos de Pancreatitis aguda de etiología biliar, en los cuales se practicó esfinteretomía endoscópica como parte fundamental de su tratamiento, entre 1987 a 1991. Se tuvieron en cuenta las siguientes variablaes: edad, sexo, antecedentes de patología biliar previa, criterios de Ranson; tiempo de evolución la enfermedad (fase aguda), que corresponde al tiempo transcurrido entre el inicio de los síntomas y el diagnóstico; Tiempo entre el diagnóstico y la Esfinteretomía endoscópica, es de notar que el 88.2 por ciento (15 pts) se practicó antes de las primeras 24 horas, factor de excelente pronóstico para el trabajo, porque es el tiempo en que creemos que se puede cambiar el curso de la enfermedad con el procedimiento; procedimiento con todas sus variables, encontrando un 100 por ciento de éxito, por lograr drenaje adecuado de la via biliar, con extracción de cálculo visible en el 53.3 por ciento (9 ptes) y expulsión posterior en 17.6 por ciento (3 ptes), uso de cateter nasobiliar en 2 ptes y uso de anestesia general en solo 2 ptes, lo que demuestra una buena tolerancia al procedimiento, las complicaciones fueron del 5.8 por ciento (1 pte) que presenta HDVA, de facil manejo; tiempo de recuperación que fue de 10.3 dias, métodos diagnósticos, tiempo de normalización de las amilasas, que fué de 3.3 días el cual es muy corto. Planteamos la esfinteretomía como una nueva alternativa en el tratamiento de la Pancreatitis aguda de etiología biliar, que presenta una morbilidad y mortalidad menor que cualquiera de los procedimientos quirúrgicos, logrando un drenaje adecuado y temprano de la vía biliar y alterando de alguna manera el curso de la enfermedad. Pensamos que en el tratamiento de urgencia,es la conducta casi ideal de intervencionismo inmediato pero no operatorio


Subject(s)
Sphincterotomy, Endoscopic , Pancreatitis/therapy
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