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1.
Small ; : e2406249, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221532

RESUMO

Aqueous Zn-ion batteries (AZIBs) are promising energy-storage devices owing to their exceptional safety, long cycle life, simple production, and high storage capacity. Manganese oxides are considered potential cathode materials for AZIBs, primarily because of their safety, low cost, simple synthesis, and high storage capacity. However, MnO2-based cathodes tend to deteriorate structurally during long-term cycling, which reduces their reversible capacity. In this study, an advanced α-MnO2@SnO2 nanocomposite via facile hydrothermal synthesis is developed. The synergistic effects of lattice disorder and increased electron conductivity in the α-MnO2@SnO2 nanocomposite mitigate structural degradation and enhance the overall electrochemical performance. The nanocomposite exhibits a high reversible capacity of 347 mAh g-1 at a current density of 100 mA g-1 after 50 cycles. Furthermore, it exhibits excellent rate performance and stable capacity even after 1000 cycles, maintaining a capacity of 78 mAh g-1 at a high current density of 5 A g-1. This excellent electrochemical performance is attributed to the reversible Zn intercalation in α-MnO2@SnO2 nanocomposites due to the increased structural stability and fast ion/electron exchange caused by the distortion of the tunnel structure, on the basis of various ex situ experiments, density functional theory calculations, and electrochemical characterizations.

2.
J Perinat Med ; 52(2): 143-149, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38102892

RESUMO

OBJECTIVES: To compare the frequency of Ureaplasma-positive gastric fluid (GF) cultures based on the cause and mode of delivery in preterm newborns. METHODS: This retrospective cohort study included women with a singleton pregnancy who delivered prematurely (between 23+0 and 32+0 weeks of gestation, n=464) at a single university hospital in South Korea. The newborns' GF was obtained on the day of birth via nasogastric intubation. The frequency of Ureaplasma spp. in GF cultures was measured and compared according to the cause and mode of delivery. RESULTS: Ureaplasma spp. was detected in 20.3 % of the GF samples. The presence of Ureaplasma spp. was significantly higher in the spontaneous preterm birth group than in the indicated preterm birth group (30.2 vs. 3.0 %; p<0.001). Additionally, Ureaplasma spp. was more frequently found in the vaginal delivery group than in the cesarean delivery group, irrespective of the cause of preterm delivery [indicated preterm birth group (22.2 vs. 1.9 %, p=0.023); spontaneous preterm birth group (37.7 vs. 24.2 %, p=0.015)]. CONCLUSIONS: Ureaplasma spp. were found in 20.3 % of the GFs. However, only 1.9 % of newborns in the indicated preterm birth group with cesarean delivery had a Ureaplasma-positive GF culture.


Assuntos
Corioamnionite , Nascimento Prematuro , Humanos , Gravidez , Recém-Nascido , Feminino , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Líquido Amniótico , Ureaplasma , Parto , Corioamnionite/etiologia
3.
BMC Pediatr ; 23(1): 137, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991415

RESUMO

BACKGROUND: This study aimed to evaluate whether mucous fistula refeeding (MFR) is safe and beneficial for the growth and intestinal adaptation of preterm infants with enterostomies. METHODS: This exploratory randomized controlled trial enrolled infants born before 35 weeks' gestation with enterostomy. If the stomal output was ≥ 40 mL/kg/day, infants were assigned to the high-output MFR group and received MFR. If the stoma output was < 40 mL/kg/day, infants were randomized to the normal-output MFR group or the control group. Growth, serum citrulline levels, and bowel diameter in loopograms were compared. The safety of MFR was evaluated. RESULTS: Twenty infants were included. The growth rate increased considerably, and the colon diameter was significantly larger after MFR. However, the citrulline levels did not significantly differ between the normal-output MFR and the control group. One case of bowel perforation occurred during the manual reduction for stoma prolapse. Although the association with MFR was unclear, two cases of culture-proven sepsis during MFR were noted. CONCLUSIONS: MFR benefits the growth and intestinal adaptation of preterm infants with enterostomy and can be safely implemented with a standardized protocol. However, infectious complications need to be investigated further. TRIAL REGISTRATION: clinicaltrials.gov NCT02812095, retrospectively registered on June 6, 2016.


Assuntos
Enterocolite Necrosante , Enterostomia , Fístula , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Citrulina , Intestinos , Enterocolite Necrosante/cirurgia
4.
J Pediatr ; 247: 53-59.e1, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35460702

RESUMO

OBJECTIVE: To compare the effects of noninvasive neurally adjusted ventilatory assist (NIV-NAVA) to nasal continuous positive airway pressure (NCPAP) in achieving successful extubation in preterm infants. STUDY DESIGN: This prospective, single-center, randomized controlled trial enrolled preterm infants born at <30 weeks of gestation who received invasive ventilation. Participants were assigned at random to either NIV-NAVA or NCPAP after their first extubation from invasive ventilation. The primary outcome of the study was extubation failure within 72 hours of extubation. Electrical activity of the diaphragm (Edi) values were collected before extubation and at 1, 4, 12, and 24 hours after extubation. RESULTS: A total of 78 infants were enrolled, including 35 infants in the NIV-NAVA group and 35 infants in the NCPAP group. Extubation failure within 72 hours of extubation was higher in the NCPAP group than in the NIV-NAVA group (28.6% vs 8.6%; P = .031). The duration of respiratory support and incidence of severe bronchopulmonary dysplasia were similar in the 2 groups. Peak and swing Edi values were comparable before and at 1 hour after extubation, but values at 4, 12, and 24 hours after extubation were lower in the NIV-NAVA group compared with the NCPAP group. CONCLUSIONS: In the present trial, NIV-NAVA was more effective than NCPAP in preventing extubation failure in preterm infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02590757.


Assuntos
Recém-Nascido Prematuro , Suporte Ventilatório Interativo , Extubação , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos , Respiração
5.
Ann Allergy Asthma Immunol ; 128(2): 193-198, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34626783

RESUMO

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a rare non-immunoglobulin E-mediated food allergy with necrotizing enterocolitis (NEC)-like symptoms which requires differential diagnosis as treatments differ. OBJECTIVE: To evaluate the clinical, laboratory, and radiologic findings that differentiate FPIES from NEC in preterm and term infants. METHODS: Clinical features, comorbidities, and laboratory and radiologic findings of neonates with presumed NEC were reviewed retrospectively and compared between FPIES and NEC in preterm and term infants who were admitted to the neonatal intensive care unit at Seoul National University Bundang Hospital between May 2003 and February 2020. RESULTS: A total of 10 of 150 (6.7%) preterm and 17 of 38 (44.7%) term infants with presumed NEC were confirmed to have FPIES; the remainder had NEC by modified Bell's criteria. Demographics and comorbidities were similar between these groups. Symptoms such as hematochezia, shock, leukocytosis, peripheral eosinophilia, and feeding of extensively hydrolyzed milk formula or elemental formula after discharge were significantly different between the 2 groups in term infants (P <.05), but not in preterm infants. On abdominal ultrasonography, pneumatosis intestinalis was more common among preterm FPIES (44.4%) than NEC cases (21.6%) (P =.04). Among the preterm infants, 4 FPIES (40%) and 25 NEC (17.9%) cases required surgery (P =.10). CONCLUSION: Differentiating FPIES in neonates suspected of having NEC is important as dietary elimination of the triggering milk protein can be recommended instead of prolonged fasting and antibiotic treatment, which are indicated for NEC, in both term and preterm infants.


Assuntos
Enterocolite Necrosante , Enterocolite , Doenças do Recém-Nascido , Enterocolite/diagnóstico , Enterocolite Necrosante/diagnóstico , Enterocolite Necrosante/cirurgia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Estudos Retrospectivos
6.
J Pediatr Orthop ; 42(1): e55-e58, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619721

RESUMO

INTRODUCTION: Identifying risk factors associated with developmental dysplasia of the hip (DDH) is essential for early diagnosis and treatment. Breech presentation is a major DDH risk factor, possibly because of crowding of the fetus within the uterus. In multifetal pregnancy, fetuses are generally smaller than singletons, which may obscure the effect of breech presentation on fetal hips. Only a few studies have investigated the occurrence of DDH in multifetal pregnancies. In this study, we aimed to evaluate whether the breech presentation is a major risk factor of DDH in twin pregnancies. METHODS: This retrospective study included 491 consecutive live births (after 23+0 weeks gestation) delivered through cesarean section with at least 1 baby with noncephalic presentation in single or twin pregnancies from April 2013 to October 2018. We analyzed the incidence of DDH and its associated factors, including sex, breech, and multifetal pregnancy, with a generalized linear mixed model. RESULTS: The incidence of DDH was 12.5% in singleton with breech presentation, 9.8% in twin-breech presentation, and 0.7% in twin-cephalic presentation. Multivariate analysis showed that singleton-breech presentation (P=0.003), twin-breech presentation (P=0.003), and female sex (P=0.008) were independent risk factors for DDH. CONCLUSION: Breech presentation is an independent risk factor for DDH in twin pregnancies, although twin pregnancy itself is not an independent risk factor for DDH.


Assuntos
Apresentação Pélvica , Displasia do Desenvolvimento do Quadril , Luxação Congênita de Quadril , Apresentação Pélvica/epidemiologia , Cesárea , Feminino , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/epidemiologia , Luxação Congênita de Quadril/etiologia , Humanos , Gravidez , Estudos Retrospectivos , Fatores de Risco
7.
Small ; 17(30): e2100146, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34145759

RESUMO

Layered transition metal oxides, in particular P2-type ones, are considered as promising cathode materials for sodium-ion batteries on account of their high specific capacity and rate capability. Nevertheless, conventional layered compounds involve detrimental phase transformation throughout repeated cycles, which results in electrochemical performance degradation. Therefore, finding structurally stable layered compounds, featuring minimal phase transition has been a key theme of the sodium-ion battery research. Here lithium substituted Fe/Mn-based P2/O3 layered oxide-Na0.67 Li0.2 Fe0.2 Mn0.6 O2 -that overcomes the inherited structural instability, is reported. In situ synchrotron-based diffraction measurements and DFT calculations are utilized, in order to identify the association between P2/O3 biphasic structure and electrochemical performances. The lithium honeycomb ordering within the P2/O3 biphasic layered compound effectively constrains the undesirable phase transitions; more specifically, both P2-Z phase transition and Jahn-Teller distortion are suppressed throughout wide potential range of 1.5-4.5 V. The DFT calculation further discovers that the presence of honeycomb ordering is crucial for achieving the structural stability by forming Na-vac-Li and Na-Li-Na pairing at highly charged state. The results highlight that the synergetic effect of P2/O3 biphasic structure and lithium substitution can provide an effective strategy toward achieving electrochemically stable layered cathode material for sodium-ion batteries.

8.
BMC Pediatr ; 21(1): 114, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685414

RESUMO

BACKGROUND: Several studies have suggested that adverse neurodevelopment could be induced by systemic inflammation in preterm infants. We aimed to investigate whether preterm infants with systemic inflammation would have impaired neurodevelopment and which biomarkers and neurophysiologic studies during inflammation are associated with poor neurodevelopment. METHODS: This prospective cohort study enrolled infants born before 30 weeks of gestation or with birth weight < 1250 g. Infants were grouped according to the presence of systemic inflammation: Control (no inflammation, n = 49), I (systemic inflammation, n = 45). Blood and cerebrospinal fluid samples for markers of brain injury and inflammation were collected and amplitude-integrated electroencephalography (aEEG) was performed within 4 h of septic workup. We evaluated aEEG at 35 weeks postmenstrual age (PMA), head circumference at 36 weeks PMA, and brain MRI at discharge. The Bayley Scales of Infant and Toddler Development III (Bayley-III) was performed at a corrected age (CA) of 18 months. RESULTS: The I group had more white matter injuries (2 vs. 26.7%, Control vs. I, respectively) at the time of discharge, lower brain functional maturation (9.5 vs. 8), and smaller head size (z-score - 1.45 vs. -2.12) at near-term age and poorer neurodevelopment at a CA of 18 months than the control (p < 0.05). Among the I group, the proportion of immature neutrophils (I/T ratios) and IL-1 beta levels in the CSF were associated with aEEG measures at the day of symptom onset (D0). Seizure spike on aEEG at D0 was significantly correlated with motor and social-emotional domains of Bayley-III (p < 0.05). The I/T ratio and CRP and TNF-α levels of blood at D0, white matter injury on MRI at discharge, head circumference and seizure spikes on aEEG at near-term age were associated with Bayley-III scores at a CA of 18 months. CONCLUSIONS: Systemic inflammation induced by clinical infection and NEC are associated with neurodevelopmental impairment in preterm infants. The seizure spike on aEEG, elevated I/T ratio, CRP, and plasma TNF-alpha during inflammatory episodes are associated with poor neurodevelopment.


Assuntos
Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Desenvolvimento Infantil , Eletroencefalografia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Inflamação , Estudos Prospectivos
9.
BMC Pediatr ; 21(1): 373, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465300

RESUMO

BACKGROUND: Adverse metabolic outcomes later in life have been reported among children or young adults who were born as preterm infants. This study was conducted to examine the impact of very preterm/very low birth weight (VP/VLBW) birth and subsequent growth after hospital discharge on cardiometabolic outcomes such as insulin resistance, fasting glucose, and systolic and diastolic blood pressure (BP) among children at 6-8 years of age. METHODS: This retrospective cohort study included children aged 6-8 years and compared those who were born at < 32 weeks of gestation or weighing < 1,500 g at birth (n = 60) with those born at term (n = 110). Body size, fat mass, BP, glucose, insulin, leptin, adiponectin, and lipid profiles were measured. Weight-for-age z-score changes between discharge and early school-age period were also calculated, and factors associated with BP, fasting glucose, and insulin resistance were analyzed. RESULTS: Children who were born VP/VLBW had significantly lower fat masses, higher systolic BP and diastolic BP, and significantly higher values of fasting glucose, insulin, and homeostatic model assessment of insulin resistance (HOMA-IR), compared to children born at term. VP/VLBW was correlated with HOMA-IR and BPs after adjusting for various factors, including fat mass index and weight-for-age z-score changes. Weight-for-age z-score changes were associated with HOMA-IR, but not with BPs. CONCLUSIONS: Although children aged 6-8 years who were born VP/VLBW showed significantly lower weight and fat mass, they had significantly higher BPs, fasting glucose, HOMA-IR, and leptin levels. The associations of VP/VLBW with cardiometabolic factors were independent of fat mass and weight gain velocity.


Assuntos
Doenças Cardiovasculares , Resistência à Insulina , Nascimento Prematuro , Assistência ao Convalescente , Criança , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Alta do Paciente , Gravidez , Estudos Retrospectivos , Instituições Acadêmicas , Adulto Jovem
10.
J Korean Med Sci ; 36(39): e260, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34636503

RESUMO

BACKGROUND: School-aged children born very preterm have been suggested to have worse cognitive and behavioral outcomes than children born full-term. Executive function (EF) is a higher level of cognitive function related to academic achievement. The present study aimed to evaluate the cognitive (including EF) and behavioral outcomes of Korean children born extremely preterm (EP) and to analyze any biological or socioeconomic risk factors for poor cognitive outcomes in this population. METHODS: A total of 71 infants weighing < 1,000 g at birth or born before 30 weeks of gestation (EP group) who were admitted to the neonatal intensive care unit from 2008 to 2009 were included in this study and compared with 40 term-birth controls. The Korean Wechsler Intelligence Scale for Children-Fourth Edition, Advanced Test of Attention (ATA), Stroop test, Children's Color Trails Test (CCTT), and Wisconsin Card Sorting Test (WCST) were used. Additionally, the Korean Child Behavior Checklist (K-CBCL) and Korean ADHD Rating Scale (K-ARS) were completed. Perinatal and demographic data were collected and analyzed. RESULTS: The mean full-scale intelligence quotient (FSIQ) score in the EP group was significantly lower than that of the term control group (89.1 ± 18.3 vs. 107.1 ± 12.7; P < 0.001). In the EP group, 26 (37%) children had an FSIQ score below 85, compared to only one child (3%) in the control group. Furthermore, the EP group showed significantly worse EF test results (ATA, Stroop test, CCTT, WCST). Except for the higher social immaturity subscore in the EP group, the K-CBCL and K-ARS scores were not different between the two groups. EP children who received laser treatment for retinopathy of prematurity (ROP) had an 8.8-fold increased risk of a low FSIQ score, and a 1-point increase in the discharge weight Z-score decreased the risk of a low FSIQ score by approximately half in this EP cohort. CONCLUSION: This is the first Korean study to investigate the cognitive and behavioral outcomes of school-aged children born EP. In the study cohort, EP children exhibited significantly lower FSIQ scores and EF than their full-term peers, and 37% of them had cognitive problems. Nonetheless, except for social immaturity, the behavioral problems were not different in EP children. Severe ROP and low discharge weight Z-score were identified as independent risk factors for low FSIQ score after adjusting for birth weight.


Assuntos
Transtornos do Comportamento Infantil/diagnóstico , Cognição/fisiologia , Estudos de Casos e Controles , Criança , Feminino , Seguimentos , Idade Gestacional , Humanos , Lactente Extremamente Prematuro , Inteligência , Masculino , Testes Neuropsicológicos , República da Coreia , Fatores de Risco , Fatores Socioeconômicos
11.
Pediatr Nephrol ; 35(12): 2369-2372, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32870361

RESUMO

BACKGROUND: Various perinatal morbidities may adversely affect postnatal nephrogenesis in preterm infants. Kidney ultrasonographic findings following acute kidney injury (AKI) have not been well described in preterm infants. Herein, we describe three cases of extremely preterm infants who showed abnormal kidney ultrasonographic findings resembling dysplasia of the kidneys following AKI. CASE-DIAGNOSIS/TREATMENT: Their median gestational age and birth weight were 25+6 (range 23+3-26+6) weeks and 620 (480-840) g, respectively. All infants suffered severe AKI during their third to seventh week of life. Their kidney function recovered with conventional management. Kidney ultrasonographies performed after AKI revealed increased kidney echogenicity, loss of corticomedullary differentiation, and multiple cortical cysts, which were similar to cystic dysplasia of the kidneys and were absent in previous kidney imaging. Three infants eventually developed at least one of the long-term kidney sequelae following AKI, including proteinuria, hypertension, and elevated levels of serum creatinine or cystatin C as determined during the last follow-up at the corrected age of 9-18 months. CONCLUSIONS: Based on these cases, we can infer that AKI occurring during the early postnatal period may result in dysplasia of the kidneys with cortical cysts in extremely preterm infants, which may lead to chronic kidney disease in their later life. It is useful to follow up not only laboratory parameters but also kidney ultrasonographic findings in extremely preterm infants who suffered AKI during their early postnatal periods.


Assuntos
Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/patologia , Creatinina/sangue , Permeabilidade do Canal Arterial/complicações , Enterocolite Necrosante/complicações , Feminino , Idade Gestacional , Humanos , Lactente , Lactente Extremamente Prematuro , Recém-Nascido , Doenças do Prematuro , Masculino , Ultrassonografia
12.
BMC Pediatr ; 19(1): 298, 2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31462232

RESUMO

BACKGROUND: Various types of noninvasive respiratory modalities that lead to successful extubation in preterm infants have been explored. We aimed to compare noninvasive neurally adjusted ventilatory assist (NIV-NAVA) and nasal continuous positive airway pressure (NCPAP) for the postextubation stabilization of preterm infants. METHODS: This retrospective study was divided into two distinct periods, between July 2012 and June 2013 and between July 2013 and June 2014, because NIV-NAVA was applied beginning in July 2013. Preterm infants of less than 30 weeks GA who had been intubated with mechanical ventilation for longer than 24 h and were weaned to NCPAP or NIV-NAVA after extubation were enrolled. Ventilatory variables and extubation failure were compared after weaning to NCPAP or NIV-NAVA. Extubation failure was defined when infants were reintubated within 72 h of extubation. RESULTS: There were 14 infants who were weaned to NCPAP during Period I, and 2 infants and 16 infants were weaned to NCPAP and NIV-NAVA, respectively, during Period II. At the time of extubation, there were no differences in the respiratory severity score (NIV-NAVA 1.65 vs. NCPAP 1.95), oxygen saturation index (1.70 vs. 2.09) and steroid use before extubation. Several ventilation parameters at extubation, such as the mean airway pressure, positive end-expiratory pressure, peak inspiratory pressure, and FiO2, were similar between the two groups. SpO2 and pCO2 preceding extubation were comparable. Extubation failure within 72 h after extubation was observed in 6.3% of the NIV-NAVA group and 37.5% of the NCPAP group (P = 0.041). CONCLUSIONS: The data in the present showed promising implications for using NIV-NAVA over NCPAP to facilitate extubation.


Assuntos
Extubação/métodos , Pressão Positiva Contínua nas Vias Aéreas , Suporte Ventilatório Interativo , Ventilação não Invasiva , Desmame do Respirador/métodos , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Oximetria , Estudos Retrospectivos , Esteroides/uso terapêutico
13.
BMC Pediatr ; 19(1): 121, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014304

RESUMO

BACKGROUND: Despite significant advances in neonatology, bronchopulmonary dysplasia (BPD) remains the most common cause of serious morbidity and mortality in premature infants. The aim of the present study was to determine associations between the respiratory severity score (RSS) with death or BPD in premature infants. METHODS: This was a retrospective study conducted between January 2010 and December 2014. We enrolled preterm infants with a gestational age of less than 28 weeks who were supported by mechanical ventilation for more than a week during the first 4 weeks of life. We collected the RSS scores on day of life 2, 7, 14, 21 and 28. The correlations between postnatal RSSs and death or severe BPD were analyzed using multivariate logistic regression. RESULTS: Of the 138 eligible infants, 66 infants (47.8%) either died or developed severe BPD. The RSS cut-off values for predicting severe BPD or death were 3.0 for postnatal day (PND) 14 with an odds ratio (OR) of 11.265 (p = 0.0006, 95% confidence interval (CI), 2.842 to 44.646), 3.6 for PND 21 with an OR of 15.162 (p = 0.0003, 95% CI, 3.467 to 66.316), and 3.24 for PND 28 with an OR of 10.713 (p = 0.0005, 95% CI, 2.825 to 40.630). CONCLUSION: Strong correlations were observed between the RSSs on PND 14, 21, and 28 and death or subsequent severe BPD. The RSS could provide a simple estimate of severe BPD or death., Further research with a larger study population is necessary to validate the usefulness of the RSS for predicting severe BPD or death.


Assuntos
Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/mortalidade , Mortalidade Hospitalar , Lactente Extremamente Prematuro , Respiração Artificial/efeitos adversos , Área Sob a Curva , Displasia Broncopulmonar/fisiopatologia , Estudos de Coortes , Feminino , Seguimentos , Hospitais Universitários , Humanos , Incidência , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Modelos Logísticos , Masculino , Análise Multivariada , República da Coreia , Respiração Artificial/métodos , Testes de Função Respiratória , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Análise de Sobrevida
15.
BMC Pediatr ; 19(1): 391, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664954

RESUMO

BACKGROUND: Thyroid hormones are critical for growth and brain development during the newborn period and infancy. Because of delayed maturation of the hypothalamic-pituitary-thyroid axis in preterm infants, thyroid dysfunction is common, and thyroid stimulating hormone (TSH) elevation is often delayed in preterm infants. The objective of this study was to determine the incidence of thyroid dysfunction requiring levothyroxine treatment and to identify its risk factors in preterm infants. METHODS: A retrospective cohort study was performed on preterm infants who were born before 32 gestational weeks and admitted to a single tertiary academic center for more than 8 weeks between January 2008 and December 2014. In these infants, serial thyroid function tests (TFTs) measuring serum TSH and free thyroxine (fT4) were routinely performed at 1, 3, and 6 weeks of postnatal age. RESULTS: Of the 220 preterm infants enrolled, 180 infants underwent TFTs at 1, 3, and 6 weeks of postnatal age and were included in the study. Of the 180 infants, 35 infants (19.4%) were started on levothyroxine treatment based on the results of serial TFTs. Among the 35 infants who were treated with levothyroxine, 16 infants (45.7%) had normal results on the initial TFT. Three of these 16 infants continued to have normal results on the second TFT. Thyroid dysfunction requiring levothyroxine treatment was significantly associated with maternal pregnancy-induced hypertension (adjusted odds ratio 2.64, 95% confidence interval 1.02-6.81). CONCLUSIONS: Thyroid dysfunction requiring levothyroxine treatment occurred in nearly one-fifth of preterm infants born before 32 gestational weeks. Nearly half of the preterm infants who were treated with levothyroxine had normal TSH and fT4 levels at 1 week of postnatal age. The findings of the present study suggest that serial TFTs is important to find preterm infants who require levothyroxine treatment.


Assuntos
Doenças da Glândula Tireoide/tratamento farmacológico , Tiroxina/uso terapêutico , Feminino , Idade Gestacional , Terapia de Reposição Hormonal/métodos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Estudos Retrospectivos , Doenças da Glândula Tireoide/sangue , Doenças da Glândula Tireoide/diagnóstico , Testes de Função Tireóidea/estatística & dados numéricos , Tireotropina/sangue , Tiroxina/sangue
16.
Small ; 14(4)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29171687

RESUMO

To date, the possible depletion of lithium resources has become relevant, giving rise to the interest in Na-ion batteries (NIBs) as promising alternatives to Li-ion batteries. While extensive investigations have examined various transition metal oxides and chalcogenides as anode materials for NIBs, few of these have been able to utilize their high specific capacity in sodium-based systems because of their irreversibility in a charge/discharge process. Here, the mixed Sn-S nanocomposites uniformly distributed on reduced graphene oxide are prepared via a facile hydrothermal synthesis and a unique carbothermal reduction process, producing ultrafine nanoparticle with the size of 2 nm. These nanocomposites are experimentally confirmed to overcome the intrinsic drawbacks of tin sulfides such as large volume change and sluggish diffusion kinetics, demonstrating an outstanding electrochemical performance: an excellent specific capacity of 1230 mAh g-1 , and an impressive rate capability (445 mAh g-1 at 5000 mA g-1 ). The electrochemical behavior of a sequential conversion-alloying reaction for the anode materials is investigated, revealing both the structural transition and the chemical state in the discharge/charge process. Comprehension of the reaction mechanism for the mixed Sn-S/rGO hybrid nanocomposites makes it a promising electrode material and provides a new approach for the Na-ion battery anodes.

17.
Pediatr Int ; 59(5): 540-544, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28063223

RESUMO

BACKGROUND: Severe bronchopulmonary dysplasia often leads to prolonged mechanical ventilation lasting several months. Cyanotic episodes frequently occur in these patients, necessitating long-term sedation and/or intermittent muscle paralysis. Neurally adjusted ventilatory assist (NAVA) might provide precisely the amount of support that these patients need without sedation. METHODS: We reviewed the medical records of preterm infants who underwent tracheostomy and required mechanical ventilation for >6 months during a period of 6 years. We compared two groups of patients: those supported with NAVA for ≥2 months versus those supported by pneumatically triggered assist methods. We also evaluated any change after NAVA use in the NAVA group. RESULTS: Among 14 prematurely born patients who received prolonged ventilation, nine were supported with NAVA and five were supported using other ventilator modes. Duration of continuous sedation was significantly shorter and the bolus use of sedatives was also significantly lower in the NAVA group than in the pneumatically triggered assist group. In addition, the NAVA group received a lower dose of dexamethasone than the pneumatically triggered assist group. Compared with before NAVA, the frequency of cyanotic episodes and of the bolus sedatives was significantly decreased after implementation of NAVA. CONCLUSIONS: For infants on prolonged mechanical ventilation, NAVA could reduce cyanotic episodes and the need for sedatives and dexamethasone. NAVA may be superior to pneumatically triggered modes in terms of the minimization of patient-ventilator dyssynchrony while delivering appropriate respiratory support in premature infants with tracheostomy.


Assuntos
Displasia Broncopulmonar/terapia , Suporte Ventilatório Interativo , Cianose/etiologia , Cianose/prevenção & controle , Feminino , Seguimentos , Humanos , Hipnóticos e Sedativos/administração & dosagem , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Suporte Ventilatório Interativo/efeitos adversos , Masculino , Estudos Retrospectivos , Traqueostomia , Resultado do Tratamento
18.
J Korean Med Sci ; 32(1): 115-123, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27914140

RESUMO

The aim of this study was to assess the differences in the mortality and in-hospital outcomes of preterm infants with < 28 weeks of gestation who received ibuprofen treatment according to the presence of clinical symptoms (any of oliguria, hypotension, or moderate to severe respiratory difficulty) attributable to hemodynamically-significant patent ductus arteriosus (hsPDA) at the time of first ibuprofen treatment. In total, 91 infants born from April 2010 to March 2015 were included. Fourteen infants (15.4%) received ibuprofen treatment when there were clinical symptoms due to hsPDA (clinical symptoms group). In clinical symptoms group, infants were younger (25 [23-27] vs. 26 [23-27] weeks; P = 0.012) and lighter (655 [500-930] vs. 880 [370-1,780] grams; P < 0.001). Also, the clinical risk index for babies (CRIB)-II scores were higher and more infants received invasive ventilator care ≤ 2 postnatal days. More infants received multiple courses of ibuprofen in clinical symptoms group. Although the frequency of secondary patent ductus arteriosus (PDA) ligation and the incidence of bronchopulmonary dysplasia (BPD) was higher in the clinical symptoms group in the univariate analysis, after multivariate logistic regression analysis adjusting for the CRIB-II score, birthweight, birth year, and the invasive ventilator care ≤ 2 postnatal days, there were no significant differences in mortality, frequency of secondary ligation and in-hospital outcomes including necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), BPD or death. Our data suggest that we can hold off on PDA treatment until the clinical symptoms become prominent.


Assuntos
Permeabilidade do Canal Arterial/diagnóstico , Permeabilidade do Canal Arterial/tratamento farmacológico , Ibuprofeno/uso terapêutico , Displasia Broncopulmonar/epidemiologia , Hemorragia Cerebral/etiologia , Permeabilidade do Canal Arterial/mortalidade , Ecocardiografia , Enterocolite Necrosante/etiologia , Feminino , Idade Gestacional , Hemodinâmica , Mortalidade Hospitalar , Humanos , Incidência , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Masculino , Análise Multivariada , Peptídeo Natriurético Encefálico/análise , Estudos Retrospectivos , Risco
20.
J Pediatr ; 179: 49-53.e1, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27692860

RESUMO

OBJECTIVE: To describe the clinical course and risk factors for pulmonary arterial hypertension (PAH) after ibuprofen treatment to close patent ductus arteriosus. STUDY DESIGN: All neonates weighing < 1500 g at birth who received ibuprofen to close patent ductus arteriosus and were admitted to Seoul National University Children's Hospital's neonatal intensive care unit in 2010-2014 were eligible for this study. The study population was divided into the PAH and non-PAH groups, and medical records were retrospectively reviewed. RESULTS: Of the 144 eligible infants, 10 developed PAH (6.9%). Relative to the non-PAH group, the PAH group exhibited greater respiratory severity and more frequent severe bronchopulmonary dysplasia or death before 36 weeks postmenstrual age. Multivariable analysis demonstrated that lower gestational age, birth weight in less than the third percentile for age, maternal hypertension of pregnancy, and oligohydramnios were risk factors for developing PAH after ibuprofen treatment. CONCLUSION: A high incidence of PAH after ibuprofen treatment was observed in the study population. Furthermore, younger gestational age and several prenatal conditions were identified as risk factors for developing PAH after ibuprofen treatment. Additional large cohort studies are necessary to confirm our results.


Assuntos
Inibidores de Ciclo-Oxigenase/uso terapêutico , Permeabilidade do Canal Arterial/tratamento farmacológico , Hipertensão Pulmonar/induzido quimicamente , Ibuprofeno/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Estudos Retrospectivos
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