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1.
Front Pediatr ; 11: 1269797, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900679

RESUMO

Background: Currently, the treatment of anemia in preterm infants is based on packed red blood cell (RBC) transfusions from adult donors. Oxygen (O2) is mainly transported to the tissues bound to hemoglobin (Hb). In extremely low gestational age neonates (ELGANs), fetal hemoglobin (HbF), which has a higher affinity for O2, represents up to 95% of circulating hemoglobin. During the first month of life, the majority of ELGANs will require an adult-donor RBC transfusion causing HbF levels to rapidly drop. HbA releases 50% more oxygen in peripheral tissues than HbF. Increased release of O2 in the retina is one of the main factors related to the development of retinopathy of prematurity (ROP). Collecting umbilical cord blood and using autologous umbilical cord whole blood (UCB) transfusions would contribute to maintaining physiological HbF concentrations in newborns and avoid oxygen-in-excess derived damage. Methods: This is a randomized, double-blinded, multicenter clinical trial. ELGANs ≤28 weeks of gestational age will be randomized 1:1 to receive an autologous umbilical cord blood transfusion (intervention arm) or standard transfusion of packed RBC from an adult donor (control arm) to assess ROP development. Assuming a 50% reduction in ROP incidence, 134 patients (67 per group) will be recruited. When blood transfusion is indicated, the Blook Bank will supply UCB or RCB according to the patient's group. The primary endpoint is the incidence of any ROP. Secondary endpoints are assessessment of treatment safety, results of biomarkers related to ROP and its chronology, and urine oxidative stress markers. In addition, the cellular composition of umbilical cord blood and its relationship with prematurity-related pathologies will be analyzed. All patients will be followed-up to 24 months of corrected age to evaluate their neurodevelopment. Discussion: ROP is a major cause of irreversible blindness in preterm newborns. Transfusions with adult donor blood can lead to complications, including ROP. UCB transfusions offer advantages by maintaining physiological HbF levels and potentially optimizing postnatal development. Moreover, autologous UCB transfusion could reduce risks associated with heterologous blood products, although volume collection remains challenging. UCB contains growth factors and progenitor cells that may impact ROP.

3.
Molecules ; 28(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241874

RESUMO

Wheat is critical for food security, and is challenged by biotic stresses, chiefly aphids and the viruses they transmit. The objective of this study was to determine whether aphids feeding on wheat could trigger a defensive plant reaction to oxidative stress that involved plant oxylipins. Plants were grown in chambers with a factorial combination of two nitrogen rates (100% N vs. 20% N in Hoagland solution), and two concentrations of CO2 (400 vs. 700 ppm). The seedlings were challenged with Rhopalosiphum padi or Sitobion avenae for 8 h. Wheat leaves produced phytoprostanes (PhytoPs) of the F1 series, and three types of phytofurans (PhytoFs): ent-16(RS)-13-epi-ST-Δ14-9-PhytoF, ent-16(RS)-9-epi-ST-Δ14-10-PhytoF and ent-9(RS)-12-epi-ST-Δ10-13-PhytoF. The oxylipin levels varied with aphids, but not with other experimental sources of variation. Both Rhopalosiphum padi and Sitobion avenae reduced the concentrations of ent-16(RS)-13-epi-ST-Δ14-9-PhytoF and ent-16(RS)-9-epi-ST-Δ14-10-PhytoF in relation to controls, but had little or no effect on PhytoPs. Our results are consistent with aphids affecting the levels of PUFAs (oxylipin precursors), which decreased the levels of PhytoFs in wheat leaves. Therefore, PhytoFs could be postulated as an early indicator of aphid hosting for this plant species. This is the first report on the quantification of non-enzymatic PhytoFs and PhytoPs in wheat leaves in response to aphids.


Assuntos
Afídeos , Oxilipinas , Animais , Afídeos/fisiologia , Triticum , Dióxido de Carbono , Folhas de Planta
4.
Nutrients ; 15(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36904100

RESUMO

Human milk (HM) is a complex biofluid containing a wide cell variety including epithelial cells and leukocytes. However, the cellular compositions and their phenotypic properties over the course of lactation are poorly understood. The aim of this preliminary study was to characterize the cellular metabolome of HM over the course of lactation. Cells were isolated via centrifugation and the cellular fraction was characterized via cytomorphology and immunocytochemical staining. Cell metabolites were extracted and analyzed using ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-QqTOF-MS) in the positive and negative electrospray ionization modes. Immunocytochemical analysis revealed a high variability of the number of detected cells with relative median abundances of 98% of glandular epithelial cells, 1% of leukocytes, and 1% of keratinocytes. Significant correlations between the milk postnatal age with percentage of epithelial cells and leukocytes, and with total cell count were observed. Results from the Hierarchical Cluster Analysis of immunocytochemical profiles were very similar to those observed in the analysis of the metabolomic profiles. In addition, metabolic pathway analysis showed alterations in seven metabolic pathways correlating with postnatal age. This work paves the way for future investigations on changes in the metabolomic fraction of the cellular compartment of HM.


Assuntos
Lactação , Leite Humano , Feminino , Humanos , Lactação/metabolismo , Metabolômica/métodos , Espectrometria de Massas/métodos , Aleitamento Materno , Metaboloma , Cromatografia Líquida de Alta Pressão/métodos
5.
Pediatr Res ; 94(1): 331-340, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36639516

RESUMO

BACKGROUND: Neonatal encephalopathy (NE) is a major cause of mortality and severe neurological disability in the neonatal period and beyond. We hypothesized that the degree of brain injury is reflected in the molecular composition of peripheral blood samples. METHODS: A sub-cohort of 28 newborns included in the HYPOTOP trial was studied. Brain injury was assessed by magnetic resonance imaging (MRI) once per patient and neurodevelopment at 24 months of age was evaluated using the Bayley III Scales of Infant and Toddler Development. The nuclear magnetic resonance (NMR) profile of 60 plasma samples collected before, during, and after cooling was recorded. RESULTS: In total, 249 molecular features were quantitated in plasma samples from newborns and postnatal age showed to affect detected NMR profiles. Lactate, beta-hydroxybutyrate, pyruvate, and three triglyceride biomarkers showed the ability to discern between different degrees of brain injury according to MRI scores. The prediction performance of lactate was superior as compared to other clinical and biochemical parameters. CONCLUSIONS: This is the first longitudinal study of an ample compound panel recorded by NMR spectroscopy in plasma from NE infants. The serial determination of lactate confirms its solid position as reliable candidate biomarker for predicting the severity of brain injury. IMPACT: The use of nuclear magnetic resonance (NMR) spectroscopy enables the simultaneous quantitation of 249 compounds in a small volume (i.e., 100 µL) of plasma. Longitudinal perturbations of plasma NMR profiles were linked to magnetic resonance imaging (MRI) outcomes of infants with neonatal encephalopathy (NE). Lactate, beta-hydroxybutyrate, pyruvate, and three triglyceride biomarkers showed the ability to discern between different degrees of brain injury according to MRI scores. Lactate is a minimally invasive candidate biomarker for early staging of MRI brain injury in NE infants that might be readily implemented in clinical guidelines for NE outcome prediction.


Assuntos
Lesões Encefálicas , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Doenças do Recém-Nascido , Lactente , Humanos , Recém-Nascido , Estudos Longitudinais , Ácido 3-Hidroxibutírico , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Lesões Encefálicas/diagnóstico por imagem , Ácido Láctico , Hipóxia-Isquemia Encefálica/terapia , Biomarcadores , Piruvatos , Hipotermia Induzida/métodos
6.
Antioxidants (Basel) ; 11(2)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35204182

RESUMO

Fetuses with congenital heart disease (CHD) have circulatory changes that may lead to predictable blood flow disturbances that may affect normal brain development. Hypoxemia and hypoperfusion may alter the redox balance leading to oxidative stress (OS), that can be assessed measuring stable end-products. OS biomarkers (OSB) were measured in amniotic fluid in fetuses with (n = 41) and without CHD (n = 44) and analyzed according to aortic flow, expected cyanosis after birth, and a CHD classification derived from this. Birth head circumference (HC) was used as a neurodevelopment biomarker. CHD fetuses had higher levels of ortho-Tyrosine (o-Tyr) than controls (p = 0.0003). There were no differences in o-Tyr levels considering aortic flow obstruction (p = 0.617). Fetuses with expected extreme cyanosis presented the highest levels of o-Tyr (p = 0.003). Among groups of CHD, fetuses without aortic obstruction and extreme cyanosis had the highest levels of o-Tyr (p = 0.005). CHD patients had lower HC than controls (p = 0.023), without correlation with OSB. Patients with HC < 10th percentile, presented high levels of o-Tyr (p = 0.024). Fetuses with CHD showed increased OSB and lower HC when compared to controls, especially those with expected extreme cyanosis. Our results suggest that increased levels of OSB are more influenced by the effect of low oxygenation than by aortic flow obstruction. Future studies with larger sample size are needed to further investigate the role of OSB as an early predictor of neurodevelopmental problems in CHD survivors.

7.
Free Radic Biol Med ; 179: 164-169, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34971756

RESUMO

Oxidative stress in the fetal period is associated with preterm birth as well as short and long-term adverse clinical outcomes. Here, an Ultra-Performance Liquid Chromatography-tandem Mass Spectrometry (UPLC-MS/MS) method for the simultaneous quantification of biomarkers of oxidative stress-derived damage to proteins and DNA in amniotic fluid (AF) samples is presented. Appropriate accuracy and precision levels, as well as sensitivity with limits of detection in the low nanomolar (<2 nM) range were achieved. The analytical method was applied to a set of AF samples and reference ranges of the biomarker panel are presented. Median concentrations of biomarkers of protein oxidation (ortho-, 3-chloro-, and 3-nitrotyrosine) and their precursors (para-tyrosine and phenylalanine) ranged between 0.6 and 3 nM and 23 and 30 µM, respectively, while levels of a biomarker of DNA-oxidation (8-hydroxydeoxyguanosine, 8OHdG) and its precursor (2'-deoxyguanosine) were found to be 0.18 and 3 nM, respectively. Detection frequencies of all metabolites were 100% with exception of 3-chlorotyrosine (3Cl-Tyr) and 8OHdG, that were only detected in 8% of samples. The developed method may be applied in research studies focusing on oxidative stress-related complications during pregnancy.


Assuntos
Nascimento Prematuro , Espectrometria de Massas em Tandem , Líquido Amniótico , Biomarcadores , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Feminino , Humanos , Recém-Nascido , Estresse Oxidativo , Gravidez
9.
Antioxid Redox Signal ; 35(17): 1467-1475, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34409848

RESUMO

The pathogenesis and progression of hypoxic-ischemic encephalopathy (HIE), a major cause of severe neurological disability and mortality in the perinatal period, are shaped by the interplay of multiple processes, including inflammation, oxidative stress, and excitotoxicity. We conducted a longitudinal study to determine biomarkers of oxidative stress and inflammation in noninvasive urine samples of newborns with moderate/severe HIE (N = 51), employing liquid chromatography-mass spectrometry. We noted that levels of several biomarkers of oxidative stress increased over time, demonstrating the ongoing propagation of oxidative injury. Prostaglandins, in contrast, showed a decreasing trend in their concentration profiles over time, which probably reflects their mediation in pathogenic mechanisms, including the inflammatory response. Statistically significant differences in the levels of oxidative stress of neonates with distinct brain lesion patterns, as detected with magnetic resonance imaging (MRI), were observed, revealing an increase of lipid peroxidation biomarkers in newborns with cerebral lesions (MRI score of 1 compared with scores of 0 and 2). Moreover, a gender-dependent study showed no statistically significant differences in biomarker concentrations between male and female infants. Our observation leads to the hypothesis that monitoring of noninvasive lipid peroxidation biomarkers could aid in diagnosis and prediction of long-term outcomes as a complementary tool to standard exploration. Antioxid. Redox Signal. 35, 1467-1475.


Assuntos
Lesões Encefálicas , Hipóxia-Isquemia Encefálica , Biomarcadores , Lesões Encefálicas/diagnóstico , Feminino , Humanos , Hipóxia-Isquemia Encefálica/diagnóstico , Lactente , Recém-Nascido , Peroxidação de Lipídeos , Estudos Longitudinais , Masculino , Gravidez
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