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INTRODUCTION: The use of different growth charts can lead to confusion in discussions between professionals. There are obstetric charts (of fetal growth) and neonatal charts (of measurements at birth and of postnatal growth). These charts can be descriptive (derived from an unselected population) or prescriptive (derived from of a population at low risk and with optimal conditions for growth). OBJECTIVES: (1) To describe available charts for infants at birth and in the neonatal period and compare them, and (2) to recommend one or more charts for use in neonatology in France. METHODS: Bibliographic research was conducted on MEDLINE and completed by the guidelines of professional societies. RESULTS: Antenatal information about fetal growth restriction or fetuses identified as small-for-gestational-age using Intrauterine charts must be integrated into the identification of newborns at risk, but the use of Intrauterine charts to evaluate birthweight is not recommended to allow consistency with postnatal charts used in neonatal practice. Z-score variations using the updated Fenton postnatal charts are the most appropriate for the assessment of birthweight and postnatal growth for infants born preterm. These charts are sex-specific, include the three measurements (length, weight, and head circumference) and enable longitudinal follow-up of growth up to 50 weeks of corrected age and are linked to the World Health Organization charts at term. The French Audipog charts, although are individualized, accessible online and can be used in maternity units to evaluate birthweight for term infants, but do not allow the follow-up of postnatal growth, while Fenton charts may be used to evaluate birthweight and postnatal growth in the first month for hospitalized term infants. CONCLUSION: The updated Fenton charts are the neonatal charts that best suit the objectives of pediatricians in France for monitoring the growth of preterm newborns. The use of the Audipog charts at term remains an alternative in maternity wards, while Fenton charts can be used for hospitalized term newborns.
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Peso ao Nascer , Gráficos de Crescimento , Humanos , Recém-Nascido , França , Feminino , Desenvolvimento Fetal , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Masculino , Neonatologia/normas , Neonatologia/métodos , Retardo do Crescimento Fetal/diagnóstico , Idade Gestacional , Gravidez , Peso CorporalRESUMO
BACKGROUND: Feeding supplemented mother milk during hospital stay improves neurodevelopment in preterm infants. Yet the composition of mother milk varies widely between subjects. The relationship between this variation and outcome is unknown. OBJECTIVE: To determine whether the protein content in native breast milk (BM) correlates with 2-year infant outcome. DESIGN: In a monocentric prospective observational study, LACTACOL, preterm infants born between 28 and 34 weeks of gestation, whose mothers decided to exclusively breastfeed, were enrolled during the first week of life. Samples of expressed breast milk obtained at several times of the day were pooled over a 24-h period, and such pool was used for macronutrient analysis, using mid-infrared analyzer. Age and Stages questionnaire (ASQ) was used to assess 2-year neurodevelopmental outcome. We analyzed the relationship between protein content in BM, and (i) infant neurodevelopment at 2-year (primary outcome), and (ii) growth until 2-year (secondary outcome). RESULTS: 138 infants were enrolled. The main analysis concerned 130 infants (including 40 twin infants) and 110 mothers with BM samples collected at week 3 after birth. Native BM samples were ranked in three tertiles of protein content (g/100 ml): 0.91 ± 0.09 (lower), 1.14 ± 0.05 (middle) and 1.40 ± 0.15 (upper); 48, 47 and 35 infants were ranked, respectively, in these three tertiles. Infants in the upper tertile were more often singleton (P = 0.012) and were born with lower birth weight and head circumference Z-scores (P = 0.005 and 0.002, respectively). Differences in weight and head circumference were no longer observed at 2-year. ASQ score at age 2 did not differ between the three tertiles (P = 0.780). Sensitivity analyses with imputations, including all 138 infants, confirmed the main analysis as well as analyses based on fortified BM as exposure. CONCLUSIONS: Protein content of BM (native or fortified) is not associated with preterm infant neurodevelopment at 2-year. Higher protein content was associated with a lower birth weight.
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Proteínas do Leite , Leite Humano , Pré-Escolar , Feminino , Alimentos Fortificados , Humanos , Lactente , Fórmulas Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro , Aumento de PesoRESUMO
Preterm infants have a deficit of fat-free mass accretion during hospitalization. This study suggests that z score of fat-free mass at discharge is associated with neurologic outcome (P = .003) at 2 years of age, independent of sex, gestational age, and birth weight z score. Interventions to promote quality of growth should be considered.
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Composição Corporal , Doenças do Prematuro/etiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Transtornos do Neurodesenvolvimento/etiologia , Desenvolvimento Infantil , Pré-Escolar , Feminino , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Doenças do Prematuro/epidemiologia , Unidades de Terapia Intensiva Neonatal , Masculino , Transtornos do Neurodesenvolvimento/epidemiologia , Alta do Paciente , Pletismografia , Estudos ProspectivosRESUMO
Very premature and/or low-birth-weight infants are at risk of developing necrotizing ulcerative enterocolitis (NEC). Prophylactic use of probiotics would change the composition of the gut microbiota and thus reduce the risk of NEC. In order to choose a probiotic at the local level, international recommendations were compared, and the available specialties were listed. Discrepancies between the different recommendations appeared, and the great variability of infant specialties available, as well as their status, did not allow us to select one. The local objective will therefore be to participate in the discussion of this subject at a national level.
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OBJECTIVE: To determine whether the relative measurement of birth weight (BW) and head circumference (HC) in preterm infants is associated with neurological outcomes. METHODS: The EPIPAGE-2 Study included 3473 infants born before 32 weeks' gestation, classified based on their Z-score of BW and HC on the Fenton curves as concordant (≤1 SD apart) or discordant (>1 SD difference). We defined four mutually exclusive categories: discordant smaller BW (sBW) with BW
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Peso ao Nascer , Cabeça , Recém-Nascido Prematuro , Humanos , Recém-Nascido , Cabeça/anatomia & histologia , Feminino , Masculino , Cefalometria/métodos , Pré-Escolar , Idade Gestacional , Desenvolvimento Infantil/fisiologiaRESUMO
To determine the effects of length of gestation and sex on infant body composition, air displacement plethysmography was performed in forty-six full-term neonates at 3 d of life and during the week prior to hospital discharge in 180 preterm neonates. Fat mass, as a percentage of body weight, was higher in preterm than in term infants (13.4 (SD 4.2) v. 10.1 (sd 3.7) %, respectively; P= 0.001). The absolute amount of fat mass did not differ between preterm and full-term newborns (323 (SD 126) v. 335 (SD 138) g; P= 0.58), whereas lean body mass was lower in preterm than in term infants (2055 (SD 280) v. 2937 (SD 259) g, respectively; P< 0.001). Among full-term infants, fat mass was higher in females than in males (11.1 (SD 3.7) v. 9.0 (SD 3.3) %, respectively; P= 0.047), whereas we did not observe any sex difference in preterm infants (13.5 (SD 4.1) v. 13.4 (SD 4.3) %; P= 0.89). Our data suggest that by the time they are discharged from hospital: (1) preterm infants have a higher percentage of body fat than term neonates and (2) this is presumably due to a lesser accretion in lean body mass in the first few weeks of extra-uterine life, particularly in boys.
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Composição Corporal , Idade Gestacional , Fatores Sexuais , Tecido Adiposo , Adiposidade , Peso ao Nascer , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Feminino , Humanos , Fórmulas Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Leite Humano , Nutrição Parenteral , Estudos ProspectivosRESUMO
We report the case of a preterm infant presenting a thrombosis, discovered on ultrasound at 22 weeks of gestational age and confirmed at birth following additional examinations. We describe the anticoagulant treatment of this patient by intravenous enoxaparin, tinzaparin and rivaroxaban, from questioning to practice.
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Exposure of parenteral nutrition (PN) to light induces hydroperoxide (HPO) formation whose toxicity, especially in pediatrics, is documented. In this context, we evaluated the efficacy of photoprotection medical devices used in our institution to protect PN from degradation after two different exposures to light. A mixed oil lipid emulsion (Smoflipid®) in standard or opaque syringes and a ternary PN mixture bags (Numetah®) with or without opaque overwrap were exposed for at least 420 min to a xenon lamp. Samples of Smoflipid® in standard or opaque syringes were also exposed for 24 h to conditions reproducing those of a neonatal intensive care unit. The use of opaque syringes for Smoflipid® administration or opaque overwraps for Numetah® administration reduced HPO formation by an average of 14% and 40%, respectively, compared to standard conditions after at least 420 min to a xenon lamp. When Smoflipid® samples were administered with standard or opaque syringes and exposed to a phototherapy lamp, the fold-change in the HPO concentration increased, respectively, by 6.3 or 5.4 at 24 h compared with syringes unexposed to phototherapy lamp. Although the observed differences were non-significant, it nonetheless appears prudent to use photoprotection of PN during administration, particularly in patients with immature or compromised antioxidant capacity.
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OBJECTIVE: To identify the characteristics of early life growth associated with later overweight or obesity (OWO) in very preterm population. DESIGN: Length, weight and body mass index (BMI) were prospectively recorded from three prospective, population-based cohorts with 5 years (Loire Infant Follow-up Team (LIFT), EPIPAGE2 (Etude EPIdémiologique sur les Petits Ages GEstationnels 2)) and 15 years (EPIPAGEADO, Etude EPIdémiologique sur les Petits Ages GEstationnels-Adolescents) of follow-up. Missing data were imputed. SETTING: Regional (LIFT), national (EPIPAGE2) and multiregional (EPIPAGEADO) cohorts in France. PATIENTS: Eligible infants born before 33 weeks of gestation in 1997 (EPIPAGEADO), between 2003 and 2014 (LIFT), and in 2011 (EPIPAGE2). MAIN OUTCOME MEASURES: OWO was determined as BMI Z-score >85th percentile of the WHO reference curves at 5 years (LIFT, EPIPAGE2) and 15 years (EPIPAGEADO). RESULTS: In EPIPAGEADO, LIFT and EPIPAGE2, BMI Z-scores were known for 302 adolescents, 1016 children and 2022 children, respectively. In EPIPAGEADO, OWO was observed in 42 (13.9%, 95% CI 10.5 to 18.3) adolescents. In multivariable models, birthweight Z-score, increase in weight Z-score during neonatal hospital stay and increase in BMI between discharge and at 2 years of corrected age were positively associated with OWO at 15 years (adjusted OR (aOR)=3.65, 95% CI 1.36 to 9.76; aOR=3.82, 95% CI 1.42 to 10.3; and aOR=2.55, 95% CI 1.72 to 3.78, respectively, by Z-score), but change in length Z-score during neonatal hospital stay was negatively associated (aOR=0.41, 95% CI 0.21 to 0.78, p=0.007). These four associations with OWO assessed at 5 years were confirmed in the LIFT and EPIPAGE2 cohorts. CONCLUSIONS: Change in length Z-score during hospitalisation, a putative proxy of quality of neonatal growth, was negatively associated with risk of later OWO when change in BMI between discharge and at 2 years was included in the multivariable model.
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Recém-Nascido Prematuro , Sobrepeso , Lactente , Criança , Feminino , Adolescente , Recém-Nascido , Humanos , Sobrepeso/epidemiologia , Estudos Prospectivos , Recém-Nascido de muito Baixo Peso , Retardo do Crescimento Fetal , Obesidade/epidemiologia , Índice de Massa CorporalAssuntos
Cuidado do Lactente/métodos , Recém-Nascido Prematuro/fisiologia , Tempo de Internação/estatística & dados numéricos , Nutrição Parenteral/estatística & dados numéricos , Gêmeos , Aumento de Peso , Peso ao Nascer , Pré-Escolar , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , SonoRESUMO
BACKGROUND & AIMS: The health benefit of human milk (HM) for preterm infant development is known but the role of human milk oligosaccharides (HMOs) contained in HM remains underexplored. We explored the relationship between exposure to HMOs contained in mother's milk and growth and neurodevelopment at 2-years corrected age in preterm infants. METHODS: Exclusively breastfed preterm infants born between 27 and 34 weeks of gestation were enrolled in a monocentric prospective observational study, LACTACOL. Samples of breast milk were collected once a week for 7 weeks after birth. HMOs and sialic acid were measured by liquid chromatography. Age and Stages questionnaire (ASQ) version 2 was used to assess 2-year neurodevelopmental outcome. We analyzed the relationship between HMO content and (i) infant neurodevelopment at 2-years, and (ii) growth outcome at discharge and at 2 years. A secondary analysis was performed among Secretor(+) Lewis(+) mothers. Only associations with a false discovery rate of 10% or less according to the Benjamini-Hochberg procedure were considered significant. RESULTS: 137 preterm infants (mean gestational age of 31.3 ± 1.7 weeks, mean birth weight of 1494 g ± 336 g) born to 117 mothers (mean age of 30.8 ± 5.0 years) were enrolled. Total HMOs and most individual HMOs and sialic acid concentrations decreased with advancing postnatal age, except for lacto-N-fucopentaose-III and 3-fucosyllactose, which increased. Total HMOs were positively correlated with neonatal length growth (adjusted p = 0.012). Neither total HMOs nor any individual HMO correlated with ASQ score in the overall cohort. However, lacto-N-fucopentaose-III (LNFP-III) was significantly associated with total ASQ score (adjusted p ≤ 0.015) among the 104 infants born to Secretor(+) Lewis(+) mothers. CONCLUSIONS: In this exploratory study in very preterm infants, total HMOs and most individual HMOs, except LNFP-III, decreased with advancing postnatal age. Neither the concentration of total HMOs nor that of any individual HMO were associated with ASQ score at 2 years, except for LNFP-III in Secretor(+) Lewis(+) mothers.
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Recém-Nascido Prematuro , Leite Humano , Adulto , Aleitamento Materno , Criança , Feminino , Humanos , Lactente , Recém-Nascido , Leite Humano/química , Ácido N-Acetilneuramínico/análise , OligossacarídeosRESUMO
BACKGROUND: Different methods are used to assess the growth of preterm infants during neonatal hospital stay. The primary objective was to compare two methods for assessing growth velocity: g/kg/d according to the Patel exponential model (EM) and change in weight z-score (ZS) according to Fenton curves. The secondary objective was to highlight factors influencing the level of agreement between the two methods. METHODS: Preterm infants born before 33 weeks were included. Growth velocity was computed by EM and ZS methods and linear regression was used to predict what growth velocity by EM method would be obtained using the ZS method. Differences between EM growth velocity and EM growth velocity predicted by ZS method were then used to assess the level of agreement between the two methods. A difference between -2 and +2 g/kg/day was considered as fair agreement, greater than ± 4 g/kg/day as poor agreement, and as disagreement otherwise. RESULTS: Among the 3954 children included, we observe a fair agreement in 2471 children (62.5%), a poor agreement in 1278 (32.3%) and a disagreement in 205 children (5.2%). Birth weight and gestational age explained 31% and 25%, respectively, of the variance in the difference between the two methods. CONCLUSIONS: In more than a third of enrolled children, the two methods for measuring growth velocity disagreed substantially. As variation of weight Z-score takes into account infant gestational age and gender, it could be more suitable to analyze a population of preterm infants with a wide range of gestational age.
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Desenvolvimento Infantil/fisiologia , Gráficos de Crescimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Peso Corporal , Feminino , Idade Gestacional , Hospitalização , Humanos , Lactente , Recém-Nascido , MasculinoRESUMO
BACKGROUND: In preterm infants, neonatal weight growth is associated with neurodevelopmental outcome but is a poor indicator of growth quality. OBJECTIVE: The aim of this work was to measure the relationship between neonatal length growth and the 2-year neurological outcome in preterm infants. METHODS: A total of 2,403 infants enrolled in the LIFT cohort with gestational age less than 34â weeks were studied. Neonatal observed length growth (OLG) was calculated as the change in length Z-score between birth and discharge. Expected length growth (ELG) was estimated based on gestational age, birth weight Z-score, birth length Z-score, gender, and observed neonatal weight growth. The difference between OLG and ELG (∆OLG-ELG) was calculated as OLG - ELG, and infants were ranked into 3 classes depending on their ∆OLG-ELG (≤-0.5, -0.49 to 0.49, ≥0.50 Z-score). We explored the relationship between ∆OLG-ELG and 2-year neurodevelopmental outcome (n = 2,036), and, in a subgroup (n = 85), between ∆OLG-ELG and body composition at discharge. RESULTS: ELG was strongly predicted from the above-mentioned parameters (R2 = 0.73, p = 0.001). OLG correlated closely with gestational age (p = 0.001) but ∆OLG-ELG did not (p = 1.0). OLG was not associated with a 2-year nonoptimal outcome after adjustment for gestational age, but ∆OLG-ELG ≤-0.5 was; the crude and adjusted odds ratios were 1.63 and 1.56, respectively. ∆OLG-ELG correlated negatively with fat mass (R2 = 0.29, p = 0.006) before and after adjustment for gestational age. CONCLUSION: ∆OLG-ELG is a marker of neonatal growth that does not depend on gestational age, and may reflect quality of growth. A ∆OLG-ELG ≤-0.5 Z-score is associated with a higher risk for 2-year nonoptimal neurodevelopmental outcome.
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Desenvolvimento Infantil , Deficiências do Desenvolvimento/epidemiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Antropometria , Peso ao Nascer , Pré-Escolar , Deficiências do Desenvolvimento/etiologia , Feminino , Seguimentos , França/epidemiologia , Idade Gestacional , Hospitalização , Humanos , Lactente , Cuidado do Lactente , Recém-Nascido , Modelos Lineares , Masculino , Fatores SexuaisRESUMO
While the effects of growth from birth to expected term on the subsequent development of preterm children has attracted plentiful attention, less is known about the effects of post-term growth. We aimed to delineate distinct patterns of post-term growth and to determine their association with the cognitive development of preterm children. Data from a prospective population-based cohort of 3,850 surviving infants born at less than 35 weeks of gestational age were used. Growth was assessed as the Body Mass Index (BMI) Z-scores at 3, 9, 18, 24, 36, 48, and 60 months. Cognitive development at five years of age was evaluated by the Global School Adaptation score (GSA). Latent class analysis was implemented to identify distinct growth patterns and logistic regressions based on propensity matching were used to evaluate the relationship between identified growth trajectories and cognitive development. Four patterns of post-term growth were identified: a normal group with a Z-score consistently around zero during childhood (n = 2,469; 64%); a group with an early rapid rise in the BMI Z-score, but only up to 2 years of age (n = 195; 5%); a group with a slow yet steady rise in the BMI Z-score during childhood (n = 510; 13%); and a group with a negative Z-score growth until 3 years of age (n = 676; 18%). The group with a slow yet steady rise in the BMI Z-score was significantly associated with low GSA scores. Our findings indicate heterogeneous post-term growth of preterm children, with potential for association with their cognitive development.
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Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido Prematuro/psicologia , Peso ao Nascer , Índice de Massa Corporal , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Aprendizagem/fisiologia , Modelos Logísticos , Masculino , Estudos ProspectivosRESUMO
Homozygous frameshift variants in CNTNAP1 have recently been reported in patients with arthrogryposis and abnormal axon myelination. In two brothers with severe congenital hypotonia and foot deformities, we identified compound heterozygous variants in CNTNAP1, reporting the first causative missense variant, p.(Cys323Arg). Motor nerve conductions were markedly decreased. Nerve microscopical lesions confirmed a severe hypomyelinating process and showed loss of attachment sites of the myelin loops on the axons, which could be a characteristic of Caspr loss-of-function. We discuss the pathophysiology of the myelination process and we propose to consider this disorder as a congenital hypomyelinating neuropathy.
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Artrogripose/genética , Moléculas de Adesão Celular Neuronais/genética , Deformidades do Pé/genética , Hipotonia Muscular/genética , Artrogripose/fisiopatologia , Deformidades do Pé/fisiopatologia , Predisposição Genética para Doença , Homozigoto , Humanos , Lactente , Recém-Nascido , Masculino , Hipotonia Muscular/fisiopatologia , Mutação de Sentido Incorreto , Bainha de Mielina/genética , IrmãosRESUMO
BACKGROUND: Birth length is correlated to height at 2 years and is a predictor of adult height. However, little is known about the relationship between length growth during neonatal hospitalization and height at 2 years. OBJECTIVES: The objective was to determine the relationship between length growth during neonatal hospitalization and height at 2 years in preterm infants. METHODS: A total of 1,760 preterm infants of less than 35 weeks of gestational age were included. Neonatal length growth was defined by the difference between length Z-scores at discharge and at birth according to Olsen curves. We calculated the odds ratios (OR) before and after adjustment for the risk of being in the 1st quintile of the height Z-score at 2 years. RESULTS: Height at 2 years was positively associated with birth length (p < 0.001) and with neonatal length growth (p < 0.001), whereas birth length and neonatal length growth were inversely correlated (p < 0.001). The risk of being in the 1st quintile of the height Z-score at 2 years was significantly associated with birth length (adjusted OR = 0.43, 95% CI: 0.38-0.49, for one Z-score) and with neonatal length growth (adjusted OR = 0.66, 95% CI: 0.56-0.76, for one Z-score) before and after adjustment for perinatal variables. CONCLUSIONS: In addition to birth length, neonatal length growth was associated with height at 2 years. These findings point to the need for a close follow-up of the length of preterm infants during hospitalization, so as to start an early management of those patients.
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Estatura , Lactente Extremamente Prematuro/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Peso Corporal , Feminino , França , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Fatores SexuaisRESUMO
BACKGROUND: Human milk composition analysis seems essential to adapt human milk fortification for preterm neonates. The Miris human milk analyzer (HMA), based on mid-infrared methodology, is convenient for a unique determination of macronutrients. However, HMA measurements are not totally comparable with reference methods (RMs). OBJECTIVE: The primary aim of this study was to compare HMA results with results from biochemical RMs for a large range of protein, fat, and carbohydrate contents and to establish a calibration adjustment. METHODS: Human milk was fractionated in protein, fat, and skim milk by covering large ranges of protein (0-3 g/100 mL), fat (0-8 g/100 mL), and carbohydrate (5-8 g/100 mL). For each macronutrient, a calibration curve was plotted by linear regression using measurements obtained using HMA and RMs. RESULTS: For fat, 53 measurements were performed, and the linear regression equation was HMA = 0.79RM + 0.28 (R(2) = 0.92). For true protein (29 measurements), the linear regression equation was HMA = 0.9RM + 0.23 (R(2) = 0.98). For carbohydrate (15 measurements), the linear regression equation was HMA = 0.59RM + 1.86 (R(2) = 0.95). A homogenization step with a disruptor coupled to a sonication step was necessary to obtain better accuracy of the measurements. Good repeatability (coefficient of variation < 7%) and reproducibility (coefficient of variation < 17%) were obtained after calibration adjustment. CONCLUSION: New calibration curves were developed for the Miris HMA, allowing accurate measurements in large ranges of macronutrient content. This is necessary for reliable use of this device in individualizing nutrition for preterm newborns.
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Carboidratos da Dieta/análise , Gorduras na Dieta/análise , Proteínas do Leite/análise , Leite Humano/química , Espectrofotometria Infravermelho/normas , Calibragem , Humanos , Modelos Lineares , Padrões de Referência , Reprodutibilidade dos Testes , Espectrofotometria Infravermelho/instrumentaçãoRESUMO
BACKGROUND AND AIMS: Human breast milk is an extremely dynamic fluid containing many biologically-active components which change throughout the feeding period and throughout the day. We designed a miRNA assay on minimized amounts of raw milk obtained from mothers of preterm infants. We investigated changes in miRNA expression within month 2 of lactation and then over the course of 24 hours. MATERIALS AND METHODS: Analyses were performed on pooled breast milk, made by combining samples collected at different clock times from the same mother donor, along with time series collected over 24 hours from four unsynchronized mothers. Whole milk, lipids or skim milk fractions were processed and analyzed by qPCR. We measured hsa-miR-16-5p, hsa-miR-21-5p, hsa-miR-146-5p, and hsa-let-7a, d and g (all -5p). Stability of miRNA endogenous controls was evaluated using RefFinder, a web tool integrating geNorm, Normfinder, BestKeeper and the comparative ΔΔCt method. RESULTS: MiR-21 and miR-16 were stably expressed in whole milk collected within month 2 of lactation from four mothers. Analysis of lipids and skim milk revealed that miR-146b and let-7d were better references in both fractions. Time series (5H-23H) allowed the identification of a set of three endogenous reference genes (hsa-let-7d, hsa-let-7g and miR-146b) to normalize raw quantification cycle (Cq) data. We identified a daily oscillation of miR-16-5p. PERSPECTIVES: Our assay allows exploring miRNA levels of breast milk from mother with preterm baby collected in time series over 48-72 hours.
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MicroRNAs/análise , Leite Humano/química , Reação em Cadeia da Polimerase em Tempo Real/métodos , Ritmo Circadiano , Feminino , Humanos , Recém-Nascido Prematuro , Reação em Cadeia da Polimerase em Tempo Real/normasRESUMO
BACKGROUND: Preterm infants have a higher fat mass (FM) percentage and a lower fat-free mass (FFM) than do term infants at the time of hospital discharge. OBJECTIVE: We determined perinatal and nutritional factors that affect the body composition of preterm infants at discharge. DESIGN: A total of 141 preterm infants born at <35 wk of gestation and admitted to Nantes University Hospital Neonatology Unit over a period of 2 y were enrolled. Nutritional intake and growth were monitored during hospitalization. Body composition was assessed by using air-displacement plethysmography at discharge. FFM was compared with reference data in term infants according to sex and gestational age. RESULTS: Linear regression produced an excellent model to predict absolute FFM from perinatal characteristics and nutrition (R(2) = 0.82) but not the FM percentage (R(2) = 0.24). Gestational and postnatal ages played an equal role in absolute FFM accretion, as did the initial growth (between birth and day 5) and growth between day 5 and discharge. Antenatal corticosteroid treatment slightly reduced FFM accretion. As concerns nutritional intake, a higher protein:energy ratio at days 10 and 21 was significantly associated with decreased risk of an FFM deficit when preterm infants were compared with reference values for term infants. Boys had higher risk of an FFM deficit than did girls. CONCLUSION: The initial growth and quality of nutrition were significantly associated with absolute FFM accretion during a hospital stay in preterm infants. This trial was registered at clinicaltrials.gov as NCT01450436.