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2.
Obesity (Silver Spring) ; 31(4): 934-944, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36855025

RESUMEN

OBJECTIVE: The aim of this study was to evaluate the role of obstructive sleep apnea (OSA) treatment on heart remodeling and diastolic dysfunction in patients with metabolic syndrome (MS). METHODS: This study is a prespecified analysis of a randomized placebo-controlled trial that enrolled patients with a recent diagnosis of MS and moderate-to-severe OSA to undergo continuous positive airway pressure (CPAP) or nasal dilators (placebo) for 6 months. Patients were invited to perform a transthoracic echocardiogram by a single investigator blinded to treatment assignment. RESULTS: A total of 99 (79% men; mean [SD], age: 48 [9] years; BMI: 33 [4] kg/m2 ) completed the study. At follow-up, in the placebo group, patients had a significant increase in atrial diameter: from 39.5 (37.0-43.0) mm to 40.5 (39.0-44.8) mm (p = 0.003). CPAP prevented atrial enlargement: from 40.0 (38.0-44.0) to 40.0 (39.0-45.0) mm (p = 0.194). In patients with diastolic dysfunction at baseline, almost half had diastolic dysfunction reversibility with CPAP (in comparison with only two patients in the placebo group, p = 0.039). In the regression analysis, the chance of diastolic dysfunction reversibility by CPAP was 6.8-fold (95% CI: 1.48-50.26, p = 0.025) compared with placebo. CONCLUSIONS: In patients with MS and OSA, 6 months of CPAP therapy prevented atrial remodeling and increased the chance of diastolic dysfunction reversibility.


Asunto(s)
Fibrilación Atrial , Remodelación Atrial , Síndrome Metabólico , Apnea Obstructiva del Sueño , Masculino , Humanos , Persona de Mediana Edad , Femenino , Presión de las Vías Aéreas Positiva Contínua , Síndrome Metabólico/complicaciones , Síndrome Metabólico/terapia , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia
3.
Chest ; 161(5): 1370-1381, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35063452

RESUMEN

BACKGROUND: OSA is associated with metabolic syndrome (MS), but it is unclear whether OSA treatment with CPAP can revert MS. RESEARCH QUESTION: Does OSA treatment with CPAP per se have effects on the MS reversibility and the associated metabolic, adiposity and vascular parameters? STUDY DESIGN AND METHODS: The TREATOSA-MS trial is a randomized placebo-controlled trial that enrolled adult patients with a recent diagnosis of MS and moderate or severe OSA (apnea-hypopnea index [AHI], ≥ 15 events/h) to undergo therapeutic CPAP or nasal dilator strips (placebo group) for 6 months. Before and after each intervention, we measured anthropometric variables, BP, glucose, and lipid profile. To control potential-related mechanisms and consequences, we also measured adiposity biomarkers (leptin and adiponectin), body composition, food intake, physical activity, subcutaneous and abdominal fat (visceral and hepatic fat), and endothelial function. RESULTS: One hundred patients (79% men; mean age, 48 ± 9 years; BMI, 33 ± 4 kg/m2; AHI, 58 ± 29 events/h) completed the study (n = 50 per group). The mean CPAP adherence was 5.5 ± 1.5 h/night. After 6 months, most patients with OSA randomized to CPAP retained the MS diagnosis, but the rate of MS reversibility was higher than observed in the placebo group (18% vs 4%; OR, 5.27; 95% CI, 1.27-35.86; P = .04). In the secondary analysis, CPAP did not promote significant reductions in the individual components of MS, weight, hepatic steatosis, lipid profile, adiponectin, and leptin, but did promote a very modest reduction in visceral fat and improved endothelial function (all analyses were adjusted for baseline values). INTERPRETATION: Despite the higher rate of MS reversibility after CPAP therapy as compared with placebo, most patients retained this diagnosis. The lack of significant or relevant effects on adiposity biomarkers and depots supports the modest role of OSA in modulating MS. TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02295202; URL: www. CLINICALTRIALS: gov.


Asunto(s)
Síndrome Metabólico , Apnea Obstructiva del Sueño , Adiponectina , Adulto , Presión de las Vías Aéreas Positiva Contínua , Femenino , Humanos , Leptina , Lípidos , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/terapia , Persona de Mediana Edad , Obesidad/complicaciones , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia
4.
J Spinal Cord Med ; 44(6): 966-971, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32043922

RESUMEN

OBJECTIVE: To observe the seminal plasma proteomic composition in men with spinal cord injury orally treated with probenecid, in order to observe pathways associated with increased sperm motility. STUDY DESIGN: Prospective study. SETTING: Miami Project to Cure Paralysis - University of Miami/Miller School of Medicine. PARTICIPANTS: Nine men with spinal cord injury, who agreed to participate in the study. INTERVENTION: Oral treatment with probenecid - 500 mg per day for one week, then 500 mg twice daily [1000 mg total] per day for three weeks. OUTCOME MEASURES: Semen analysis as per WHO 2010 guidelines, and seminal plasma proteomics analysis by LC-MS/MS. RESULTS: In total, 783 proteins were identified, of which, 17 were decreased, while 6 were increased after treatment. The results suggest a new pathway that could be treated by the decrease of biglycan after probenecid treatment. CONCLUSION: Oral treatment with probenecid is able to alter the seminal plasma proteome, in pathways that explain decreased innate immune response.


Asunto(s)
Semen , Traumatismos de la Médula Espinal , Cromatografía Liquida , Humanos , Masculino , Probenecid/farmacología , Probenecid/uso terapéutico , Estudios Prospectivos , Proteómica/métodos , Semen/metabolismo , Motilidad Espermática/fisiología , Espermatozoides/metabolismo , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/metabolismo , Espectrometría de Masas en Tándem
5.
Trends Cardiovasc Med ; 31(4): 242-249, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32413393

RESUMEN

Obstructive sleep apnea (OSA) is a common clinical condition associated with increased cardiovascular morbidity and mortality. Recent evidence from clinical studies and animal models suggest that OSA can promote cardiovascular disease by inducing autonomic, hemodynamic, inflammatory and metabolic dysregulation. However, most of the evidence addressing hard endpoints in humans is derived from observational studies. Several challenges have been noted in the pursuit of a comprehensive knowledge base about the impact of OSA including: 1) the precise mechanisms by which OSA causes metabolic and cardiovascular consequences are not clear, which limits our current ability to address potential targets in OSA; 2) several patients with OSA, even with severe forms, present with no or mild daytime symptoms. Beyond the obvious challenges for obtaining good adherence for conventional OSA treatments, there is evidence that symptomatic vs. asymptomatic patients with OSA do not necessarily have the same metabolic and cardiovascular outcomes; and 3) the cardiovascular response to OSA treatment may vary even in those patients with good adherence. In this scenario, there is an obvious need to develop biomarkers in the OSA research area. This review focuses on describing the advances that have occurred so far in exploring potential OSA biomarkers with clear emphasis for the cardiovascular risk. Particular attention will be devoted to discuss molecular biomarkers including the potential role of microRNAs, proteomics and metabolomics. We also discuss the major challenges and perspectives in this growing research field.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Metaboloma , Proteoma , Apnea Obstructiva del Sueño/complicaciones , Transcriptoma , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , Perfilación de la Expresión Génica , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Metabolómica , Valor Predictivo de las Pruebas , Proteómica , Medición de Riesgo , Apnea Obstructiva del Sueño/genética , Apnea Obstructiva del Sueño/metabolismo
6.
Andrologia ; 52(5): e13562, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32150769

RESUMEN

To verify a possible synergistic effect of smoking and varicocele on the seminal plasma proteome and biological functions, a cross-sectional study was performed in 25 smokers and 24 nonsmokers. Samples were used for conventional semen analysis, functional analysis (DNA fragmentation, acrosome integrity and mitochondrial activity) and proteomics by a shotgun approach. Functional enrichment of biological pathways was performed in differentially expressed proteins. Smokers presented lower ejaculate volume (p = .027), percentage of progressively motile spermatozoa (p = .002), total sperm count (p = .039), morphology (p = .001) and higher percentage of immotile spermatozoa (p = .03), round cell (p = .045) and neutrophil count (p = .009). Smokers also presented lower mitochondrial activity and acrosome integrity and higher DNA fragmentation. We identified and quantified 421 proteins in seminal plasma, of which one was exclusive, 21 were overexpressed and 70 were underexpressed in the seminal plasma of smokers. The proteins neprilysin, beta-defensin 106A and histone H4A were capable of predicting the smoker group. Enriched functions were related to immune function and sperm machinery in testis/epididymis. Based on our findings, we can conclude that cigarette smoking leads to the establishment of inflammatory protein pathways in the testis/epididymis in the presence of varicocele that seems to act in synergy with the toxic components of the cigarette.


Asunto(s)
Fumar Cigarrillos/efectos adversos , Infertilidad Masculina/inmunología , Semen/química , Proteínas de Plasma Seminal/análisis , Varicocele/complicaciones , Acrosoma/efectos de los fármacos , Acrosoma/inmunología , Acrosoma/patología , Adulto , Brasil , Estudios Transversales , Fragmentación del ADN/efectos de los fármacos , Epidídimo/irrigación sanguínea , Epidídimo/efectos de los fármacos , Epidídimo/inmunología , Humanos , Infertilidad Masculina/patología , Masculino , Persona de Mediana Edad , No Fumadores/estadística & datos numéricos , Proteómica/estadística & datos numéricos , Semen/inmunología , Semen/metabolismo , Análisis de Semen/estadística & datos numéricos , Proteínas de Plasma Seminal/metabolismo , Transducción de Señal/inmunología , Fumadores/estadística & datos numéricos , Testículo/irrigación sanguínea , Testículo/efectos de los fármacos , Testículo/inmunología , Nicotiana/toxicidad , Varicocele/inmunología , Adulto Joven
7.
Sleep Breath ; 24(4): 1463-1472, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31898194

RESUMEN

PURPOSE: Obstructive sleep apnea (OSA) is associated with multiple comorbid conditions including cardiovascular diseases and cancer. There is a growing interest in exploring biomarkers to understand the related mechanisms and improve the risk stratification of OSA. Circulating microRNAs (miRNAs) are single noncoding strands of nearly 22 nucleotides that posttranscriptionally regulate target gene expression. Our aim was to identify miRNA profiles associated with OSA. METHODS: We studied 48 male subjects, mostly Caucasian (63%) and overweight, divided by polysomnography into the no OSA control group (n = 6), mild OSA group (n = 12), moderate OSA group (n = 15), and severe OSA group (n = 15). The study groups were matched for age, body mass index (BMI), and body fat composition. miRNA profiles were measured from peripheral whole blood using two steps: (1) microarray analysis comprising more than 2500 miRNAs in a subsample of 12 subjects (three from each group); and (2) validation phase using real-time quantitative polymerase chain reaction (RTqPCR). RESULTS: The microarray assessment identified 21 differentially expressed miRNAs among the groups. The RT-qPCR assessment showed that miR-1254 and miR-320e presented a gradual increase in expression parallel to OSA severity. Linear regression analysis showed that severe OSA was independently associated with miR-1254 (ß = 68.4; EP = 29.8; p = 0.02) and miR-320e (ß = 76.1; EP = 31.3; p = 0.02). CONCLUSION: Severe OSA is independently associated with miRNAs that are involved in heart failure (miR-1254), myocardial ischemia/reperfusion (miR-320e), and cell proliferation in some cancer types (miR-1254 and miR-320e). Future investigations addressing whether these miRs may provide prognostic information in OSA are needed.


Asunto(s)
MicroARN Circulante/sangre , Insuficiencia Cardíaca/sangre , Isquemia Miocárdica/sangre , Neoplasias/sangre , Apnea Obstructiva del Sueño/sangre , Adulto , Proliferación Celular , Insuficiencia Cardíaca/complicaciones , Humanos , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Isquemia Miocárdica/complicaciones , Neoplasias/complicaciones , Sobrepeso/complicaciones , Índice de Severidad de la Enfermedad , Apnea Obstructiva del Sueño/complicaciones
8.
Sci Rep ; 8(1): 11270, 2018 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-30050090

RESUMEN

The use of metabolomic and lipidomic strategies for selecting potential biomarkers for obstructive sleep apnoea (OSA) has been little explored. We examined adult male patients with OSA (defined by an apnoea-hypopnoea index ≥15 events/hour), as well as age-, gender-, and fat-composition-matched volunteers without OSA. All subjects were subjected to clinical evaluation, sleep questionnaires for detecting the risk of OSA (Berlin and NoSAS score), metabolomic analysis by gas chromatography coupled to mass spectrometry and lipidomic analysis with liquid chromatography followed by detection by MALDI-MS. This study included 37 patients with OSA and 16 controls. From the 6 metabolites and 22 lipids initially selected, those with the best association with OSA were glutamic acid, deoxy sugar and arachidonic acid (metabolites), and glycerophosphoethanolamines, sphingomyelin and lyso-phosphocholines (lipids). For the questionnaires, the NoSAS score performed best with screening for OSA (area under the curve [AUC] = 0.724, p = 0.003). The combination of the NoSAS score with metabolites or lipids resulted in an AUC for detecting OSA of 0.911 and 0.951, respectively. In conclusion, metabolomic and lipidomic strategies suggested potential early biomarkers in OSA that could also be helpful in screening for this sleep disorder beyond traditional questionnaires.


Asunto(s)
Biomarcadores/sangre , Enfermedades Cardiovasculares/epidemiología , Lípidos/sangre , Metaboloma , Apnea Obstructiva del Sueño/diagnóstico , Apnea Obstructiva del Sueño/patología , Adulto , Brasil , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Encuestas y Cuestionarios
9.
Mar Drugs ; 16(4)2018 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-29649159

RESUMEN

Astaxanthin (ASTA) is a ketocarotenoid found in many marine organisms and that affords many benefits to human health. ASTA is particularly effective against radical-mediated lipid peroxidation, and recent findings hypothesize a "mitochondrial-targeted" action of ASTA in cells. Therefore, we examined the protective effects of ASTA against lipid peroxidation in zwitterionic phosphatidylcholine liposomes (PCLs) and anionic phosphatidylcholine: phosphatidylglycerol liposomes (PCPGLs), at different pHs (6.2 to 8.0), which were challenged by oxidizing/nitrating conditions that mimic the regular and preapoptotic redox environment of active mitochondria. Pre-apoptotic conditions were created by oxidized/nitr(osyl)ated cytochrome c and resulted in the highest levels of lipoperoxidation in both PCL and PCPGLs (pH 7.4). ASTA was less protective at acidic conditions, especially in anionic PCPGLs. Our data demonstrated the ability of ASTA to hamper oxidative and nitrative events that lead to cytochrome c-peroxidase apoptosis and lipid peroxidation, although its efficiency changes with pH and lipid composition of membranes.


Asunto(s)
Peroxidación de Lípido/efectos de los fármacos , Liposomas/química , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/química , Apoptosis/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Xantófilas/química , Xantófilas/farmacología
10.
Dermatoendocrinol ; 9(1): e1361571, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29497466

RESUMEN

Acne vulgaris is a chronic inflammatory disease that affects the pilosebaceous unit. Recent studies have shown an increasing number of cases of acne in adult women. These cases are predominantly normoandrogenic and present some clinical differences compared to adolescent acne. Local glandular metabolism turns some weak hormonal precursors into more active substances that increase the production of sebum, leaving these areas more prone to an increasing the colonization by Propionibacterium acnes (P. acnes). Our objective was to evaluate the usefulness of an androgenic metabolite as an adult female acne biomarker. The study population consisted of 38 adult women with acne without any features of hyperandrogenism and a control group. They were recruited from the clinic of Dermatology Hospital Division of São Paulo, Federal University of São Paulo from January 2012 to September 2014. After the first hormonal dosages, patients with acne were randomized into two different groups: one receiving a combined oral contraceptive (COC) containing 0,02 mg of ethinylestradiol and 3 mg drospirenone in a regimen of 24 days of medication, and the other group was treated with a topical gel containing 15% azelaic acid (AA), twice daily, both for six months. With the end of treatment new dosages were performed. Regarding the hormones, total and free testosterone and dehydroepiandrosterone sultate were quantified. In addition, the detection and quantification of androsterone glucuronate (ADT-G), an androgenic metabolite, has been developed. Only ADT-G was sensitive in detecting differences between the control and acne groups, and presented reduction of their values with systemic treatment. Therefore, only ADT-G was able to analyze the peripheral hyperandrogenism in cases of adult female acne.

11.
BJU Int ; 118(5): 814-822, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27208688

RESUMEN

OBJECTIVE: To evaluate the effect of smoking on sperm functional quality and seminal plasma proteomic profile. PATIENTS AND METHODS: Sperm functional tests were performed in 20 non-smoking men with normal semen quality, according to the World Health Organization (2010) and in 20 smoking patients. These included: evaluation of DNA fragmentation by alkaline Comet assay; analysis of mitochondrial activity using DAB staining; and acrosomal integrity evaluation by PNA binding. The remaining semen was centrifuged and seminal plasma was used for proteomic analysis (liquid chromatography-tandem mass spectrometry). The quantified proteins were used for Venn diagram construction in Cytoscape 3.2.1 software, using the PINA4MS plug-in. Then, differentially expressed proteins were used for functional enrichment analysis of Gene Ontology categories, Kyoto Encyclopedia of Genes and Genomes and Reactome, using Cytoscape software and the ClueGO 2.2.0 plug-in. RESULTS: Smokers had a higher percentage of sperm DNA damage (Comet classes III and IV; P < 0.01), partially and fully inactive mitochondria (DAB classes III and IV; P = 0.001 and P = 0.006, respectively) and non-intact acrosomes (P < 0.01) when compared with the control group. With respect to proteomic analysis, 422 proteins were identified and quantified, of which one protein was absent, 27 proteins were under-represented and six proteins were over-represented in smokers. Functional enrichment analysis showed the enrichment of antigen processing and presentation, positive regulation of prostaglandin secretion involved in immune response, protein kinase A signalling and arachidonic acid secretion, complement activation, regulation of the cytokine-mediated signalling pathway and regulation of acute inflammatory response in the study group (smokers). CONCLUSION: In conclusion, cigarette smoking was associated with an inflammatory state in the accessory glands and in the testis, as shown by enriched proteomic pathways. This state causes an alteration in sperm functional quality, which is characterized by decreased acrosome integrity and mitochondrial activity, as well as by increased nuclear DNA fragmentation.


Asunto(s)
Proteómica , Análisis de Semen/métodos , Semen/fisiología , Proteínas de Plasma Seminal/análisis , Fumar/fisiopatología , Espermatozoides/fisiología , Acrosoma , Adulto , Estudios Transversales , Fragmentación del ADN , Humanos , Masculino , Persona de Mediana Edad , Mitocondrias/fisiología , Adulto Joven
12.
Rev. bras. farmacogn ; 21(2): 202-208, mar.-abr. 2011. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-590179

RESUMEN

Qualitative and quantitative studies of mycosporine-like amino acids (MAAs) in three species of the genus Gracilaria Greville (G. birdiae, G. domingensis and G. tenuistipitata) were performed. A simple and efficient extraction procedure based on ethanol was described. HPLC, UV and mass spectrometry experiments revealed different profiles between extracts obtained from one species cultivated in the laboratory (G. tenuistipitata) and two species collected in their natural environment (G. birdiae and G. domingensis). The levels detected in the latter two species were approximately 150 times higher than in the species cultivated in vitro. This study revealed that G. birdiae and G. domingensis present a potential source for economical exploration of MAAs.

13.
J Photochem Photobiol B ; 94(3): 191-200, 2009 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-19128981

RESUMEN

Using a high-resolution reverse-phase liquid chromatography method we found that the tissues of the hermatypic coral Pocillopora capitata (collected in Santiago Bay, Mexico) contain a high diversity of primary and secondary mycosporine-like amino acids (MAAs) typical of some reef-building coral species: mycosporine-glycine, shinorine, porphyra-334, mycosporine-methylamine-serine, mycosporine-methylamine-threonine, palythine-serine, palythine and one additional novel predominant MAA, with an absorbance maximum of 320 nm. Here we document the isolation and characterization of this novel MAA from the coral P. capitata. Using low multi-stage mass analyses of deuterated and non deuterated compounds, high-resolution mass analyses (Time of Flight, TOF) and other techniques, this novel compound was characterized as palythine-threonine. Palythine-threonine was also present in high concentrations in the corals Pocillopora eydouxi and Stylophora pistillata indicating a wider distribution of this MAA among reef-building corals. From structural considerations we suggest that palythine-threonine is formed by decarboxylation of porphyra-334 followed by demethylation of mycosporine-methylamine-threonine.


Asunto(s)
Antozoos/química , Ciclohexanoles/aislamiento & purificación , Glicina/análogos & derivados , Treonina/aislamiento & purificación , Aminoácidos , Animales , Ciclohexanonas/metabolismo , Glicina/biosíntesis , Glicina/aislamiento & purificación , Glicina/metabolismo , Espectrometría de Masas/métodos , Estructura Molecular , Treonina/biosíntesis
14.
Artículo en Inglés | MEDLINE | ID: mdl-16901759

RESUMEN

In order to survive in a highly competitive environment, freshwater or marine algae have to develop defense strategies that result in a tremendous diversity of compounds from different metabolic pathways. Recent trends in drug research from natural sources have shown that algae are promising organisms to furnish novel biochemically active compounds. The current review describes the main substances biosynthesized by algae with potential economic impact in food science, pharmaceutical industry and public health. Emphasis is given to fatty acids, steroids, carotenoids, polysaccharides, lectins, mycosporine-like amino acids, halogenated compounds, polyketides and toxins.


Asunto(s)
Factores Biológicos/metabolismo , Eucariontes/metabolismo , Biología Marina/economía , Plancton/metabolismo , Adaptación Fisiológica , Factores Biológicos/química , Factores Biológicos/economía , Industria Farmacéutica/economía , Industria de Alimentos/economía , Agua Dulce , Plancton/química , Salud Pública/economía , Agua de Mar
15.
Rapid Commun Mass Spectrom ; 20(2): 253-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16345122

RESUMEN

The determination and identification of mycosporine-like amino acids (MAAs) from algae remain a major challenge due to the low concentration. Mass spectrometry (MS) can make an invaluable contribution in the search and identification of MAAs because of its high sensitivity, possibility of coupling with liquid chromatography, and the availability of powerful tandem mass spectrometric techniques. However, the unequivocal determination of the presence and location of important functional groups present on the basic skeleton of the MAAs is often elusive due to their inherent instability under MS conditions. In this study, the use of hydrogen/deuterium (H/D) exchange and electrospray ionisation tandem mass spectrometry (ESI-MS/MS) for characterisation of four MAAs (palythine, asterina, palythinol and shinorine) isolated from the macroalgae Gracilaria tenuistipitata Chang et Xia was investigated. The accurate-mass confirmation of the protonated molecules was performed on a Q-TOF instrument. We demonstrate that employing deuterium labelling in ESI-MS/MS analysis provides a convenient tool for the determination of new MAAs. Although the fragmentation patterns of MAAs were discussed earlier, to our knowledge, this is the first time that mechanisms are proposed.


Asunto(s)
Proteínas Algáceas/análisis , Aminoácidos/análisis , Medición de Intercambio de Deuterio/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Gracilaria/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Aminoácidos/química
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