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2.
J Pediatr Surg ; 59(6): 1077-1082, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38168548

RESUMO

BACKGROUND: Right-sided congenital diaphragmatic hernia (RCDH) is a rare and often fatal congenital anomaly, primarily attributed to lung hypoplasia, which is associated with small branch pulmonary artery (PA). This study investigated whether postnatal PA measurements obtained through echocardiography are associated with mortality or the extracorporeal membrane oxygenation (ECMO) requirement in neonates with RCDH. METHODS: A retrospective study was conducted on neonates with RCDH born between 2008 and 2022. Echocardiography was performed on the day of birth. The diameter of the main PA (MPA) was measured at the maximal dimension, and the diameters of the left PA (LPA) and right PA (RPA) were measured at the bifurcation. The primary outcome was mortality or ECMO requirement. Parameters, including the LPA:MPA ratio, RPA:MPA ratio, Nakata index, McGoon ratio, and ejection fraction (EF), were analyzed and compared with the observed-to-expected lung-to-head ratio (o/e LHR), initial blood gas, and defect size as predictive values. RESULTS: Among 39 neonates with RCDH, 25 (64.1 %) survived without ECMO. The non-survivor or ECMO group exhibited lower o/e LHR, reduced EF, smaller LPA and RPA diameters, and larger MPA diameter than survivors. Lower LPA:MPA ratio, Nakata index, McGoon ratio, and higher initial PaCO2 were associated with adverse outcomes. Notably, the LPA:MPA ratio showed the highest predictive capability (area under the curve, 0.983; p < 0.001). CONCLUSION: The LPA:MPA ratio is a promising postnatal predictor of mortality or ECMO requirement in neonates with RCDH. Additionally, Nakata index, McGoon ratio, and initial PaCO2 are significantly correlated with outcomes. LEVEL OF EVIDENCE: This is a level III. TYPE OF STUDY: Prognostic study.


Assuntos
Ecocardiografia , Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas , Artéria Pulmonar , Humanos , Hérnias Diafragmáticas Congênitas/mortalidade , Hérnias Diafragmáticas Congênitas/terapia , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Estudos Retrospectivos , Recém-Nascido , Artéria Pulmonar/diagnóstico por imagem , Feminino , Masculino , Prognóstico
3.
Neonatology ; 121(1): 74-80, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37866355

RESUMO

INTRODUCTION: This study aimed to investigate the outcomes of infants at 18-24 months born in the Korean Neonatal Network with a birth weight <500 g. METHODS: The anthropometric and neurodevelopmental data of infants with a birth weight <500 g at a gestational age of ≥22 weeks who were registered in the Korean Neonatal Network 2013-2017 and followed up at a corrected age of 18-24 months were reviewed. Neurodevelopmental impairment was defined as the presence of any of the following: (1) cerebral palsy; (2) severe visual impairment; (3) hearing impairment; or (4) cognitive impairment. Cognitive impairment was defined as (1) a Bayley Scales of Infant Development-II Mental Development Index score <70; and (2) Bayley Scales of Infant and Toddler Development-III Cognitive and Language Composite scores <85. Cognitive testing was performed for infants with suspected problems upon clinician's referral to developmental specialists. RESULTS: At a median corrected age of 20 months, 26/52 (50%) of included infants had neurodevelopmental impairment. Cerebral palsy, severe visual impairment, wearing of glasses, hearing impairment, and cognitive impairment occurred in 22%, 0%, 8%, 5%, and 57% of the included infants, respectively. The proportions of infants with <2 standard deviations of weight, length, and head circumference were 54%, 52%, and 56%, respectively. The majority (70%) of infants were rehospitalized, and the most common cause was respiratory problems. CONCLUSION: Half of infants with a birth weight <500 g in Korea may exhibit neurodevelopmental impairment and growth retardation at a corrected age of 18-24 months. Multidisciplinary follow-up along with continuous rehabilitation will be needed to improve neurological and physical development in this special population.


Assuntos
Paralisia Cerebral , Perda Auditiva , Recém-Nascido , Lactente , Feminino , Humanos , Pré-Escolar , Criança , Peso ao Nascer , Estudos de Coortes , Paralisia Cerebral/diagnóstico , Paralisia Cerebral/epidemiologia , Paralisia Cerebral/etiologia , Perda Auditiva/epidemiologia , Perda Auditiva/complicações , Transtornos da Visão/epidemiologia , República da Coreia/epidemiologia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Deficiências do Desenvolvimento/etiologia
4.
BMC Pediatr ; 23(1): 499, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37784067

RESUMO

BACKGROUND: To predict whether the left pulmonary artery (LPA) to the main pulmonary artery (MPA) ratio measured by echocardiography in left congenital diaphragmatic hernia (CDH) was related to death or need for extracorporeal membrane oxygenation (ECMO). METHODS: This retrospective study analyzed neonates with left CDH born between 2018 and 2022 in a single tertiary medical institution. Echocardiography was performed immediately after birth. The diameter of the LPA was measured at the bifurcation, and the diameter of the MPA was measured at the maximal dimension during the systolic phase. The Nakata index, McGoon ratio, and ejection fraction (EF) were analyzed and compared with the LPA: MPA ratio as predictive values. RESULTS: Seventy-two neonates with left CDH were included, 19 (26.4%) died or needed ECMO, and 53 (73.6%) survived without ECMO. The lower observed/expected lung-to-head ratio, lower EF, lower LPA: MPA ratio, lower RPA: MPA ratio, lower Nakata index, and lower McGoon ratio were associated with death or need for ECMO. By multivariate analysis, lower LPA: MPA ratio, RPA: MPA ratio, and Nakata index were independent postnatal risk factors for death or need for ECMO. Among the measurements, the LPA: MPA ratio had the highest area under the curve (0.957) with a sensitivity of 84.2% and specificity of 96.3% at a cut-off value of 31.2%. CONCLUSION: In patients with left CDH, the LPA: MPA ratio measured by echocardiography could be used as an independent postnatal predictor of death or need for ECMO.


Assuntos
Hérnias Diafragmáticas Congênitas , Recém-Nascido , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/terapia , Artéria Pulmonar/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos , Ecocardiografia
5.
Anal Chem ; 93(2): 792-800, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33175513

RESUMO

In this study, a signal-amplifiable nanoprobe-based chemiluminescent lateral flow immunoassay (CL-LFA) was developed to detect avian influenza viruses (AIV) and other contagious and fatal viral avian-origin diseases worldwide. Signal-amplifiable nanoprobes are capable of size-selective immobilization of antibodies (binding receptors) and enzymes (signal transducers) on sensitive paper-based sensor platforms. Particle structure designs and conjugation pathways conducive for antigen accessibility to maximum amounts of immobilized enzymes and antibodies have advanced. The detection limit of the CL-LFA using the signal-amplifiable nanoprobe for the nucleoprotein of the H3N2 virus was 5 pM. Sensitivity tests for low pathogenicity avian influenza H9N2, H1N1, and high pathogenicity avian influenza H5N9 viruses were conducted, and the detection limits of CL-LFA were found to be 103.5 50% egg infective dose (EID50)/mL, 102.5 EID50/mL, and 104 EID50/mL, respectively, which is 20 to 100 times lower than that of a commercial AIV rapid test kit. Moreover, CL-LFA demonstrated high sensitivity and specificity against 37 clinical samples. The signal-amplifiable probe designed in this study is a potential diagnostic probe with ultrahigh sensitivity for applications in the field of clinical diagnosis, which requires sensitive antigen detection as evidenced by enhanced signaling capacity and sensitivity of the LFAs.


Assuntos
Anticorpos Antivirais/química , Aves/virologia , Enzimas Imobilizadas , Proteínas Imobilizadas , Nanoestruturas , Animais , Especificidade de Anticorpos , Antígenos Virais , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/diagnóstico , Influenza Aviária/virologia , Sensibilidade e Especificidade
6.
ACS Appl Mater Interfaces ; 10(9): 7562-7573, 2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-28937738

RESUMO

A significant effort is currently being invested to improve the electrochemical performance of classical lithium-ion batteries (LIBs) or to accelerate the advent of new chemistry-based post-LIBs. Regardless of the governing chemistry associated with charge storage, stable electrode-electrolyte interface and wet-adhesion among the electrode particles are universally desired for rechargeable batteries adopting liquid electrolytes. In this regard, recent studies have witnessed the usefulness of mussel-inspired polydopamine or catechol functional group in modifying the key battery components, such as active material, separator, and binder. In particular, the uniform conformal coating capability of polydopamine protects active materials from unwanted side reactions with electrolytes and increases the wettability of separators with electrolytes, both of which significantly contribute to the improvement of key battery properties. The wet-adhesion originating from catechol functional groups also largely increases the cycle lives of emerging high-capacity electrodes accompanied by huge volume expansion. This review summarizes the representative examples of mussel-inspired approaches in rechargeable batteries and offers central design principles of relevant coating and adhesion processes.

7.
Nano Lett ; 17(3): 1870-1876, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28191851

RESUMO

Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiOx composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO4]4-. During the dynamic course of spray pyrolysis, [SiO4]4- transforms to SiOx matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiOx composite, in which Si nanodomains are homogeneously embedded in the SiOx matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g-1 at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate.

8.
ACS Comb Sci ; 19(2): 81-84, 2017 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-28045248

RESUMO

Combinatorial optical screening of aprotic electrocatalysts has not yet been achieved primarily due to H+-associated mechanisms of fluorophore modulation. We have overcome this problem by using fluorophore metal-organic complexes. In particular, eosin Y and quinine can be coordinated with various metallic cations (e.g., Li+, Na+, Mg2+, Zn2+, and Al3+) in aprotic solvents, triggering changes in their fluorescent properties. These interactions have been used in a reliable screening method to determine oxygen reduction/evolution reaction activities of 100 Mn-based binary catalysts for the aprotic Li-air battery.


Assuntos
Técnicas de Química Combinatória/métodos , Complexos de Coordenação/química , Corantes Fluorescentes/química , Lítio/química , Oxigênio/química , Catálise , Cátions/química , Fontes de Energia Elétrica , Técnicas Eletroquímicas , Amarelo de Eosina-(YS)/química , Metais/química , Modelos Moleculares , Oxirredução , Quinina/química
9.
Nanotechnology ; 26(20): 205601, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25913069

RESUMO

In this work, we demonstrate an environmentally benign and facile flash light irradiation process to reduce graphene oxide (GO). GO thin films were prepared by a vacuum filtration process, and these films were reduced by exposure to flash light irradiation for a few milliseconds at room temperature under ambient conditions. Flash light conditions such as energy, pulse width, and pulse number were varied to determine optimal conditions for this photothermal reduction of GO. The flash light irradiation treatment completely reduced the GO thin films, transforming them into pure graphene films. The resulting graphene films were characterized by x-ray diffraction, x-ray photoelectron spectroscopy, Raman spectroscopy, transmission electron microscopy, and thermogravimetric analysis.

10.
ACS Appl Mater Interfaces ; 7(10): 5674-84, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25714508

RESUMO

In this work, copper nanowires (NWs) and Cu nanoparticles (NPs) were employed to increase the reliability of a printed electrode pattern under mechanical bending fatigue. The fabricated Cu NW/NP inks with different weight fractions of Cu NWs were printed on a polyimide substrate and flash light-sintered within a few milliseconds at room temperature under ambient conditions. Then, 1000 cycles of outer and inner bending fatigue tests were performed using a lab-made fatigue tester. The flash light-sintered Cu NW/NP ink film with 5 wt % Cu NWs prepared under the flash light-sintering conditions (12.5 J·cm­2 irradiation energy, 10 ms pulse duration, and one pulse) showed a lower resistivity (22.77 µΩ·cm) than those of the only Cu NPs and Cu NWs ink (94.01 µΩ·cm and 104.15 µΩ·cm, respectively). In addition, the resistance change (ΔR·R0(­1)) of the 5 wt % Cu NWs Cu NW/NP film was greatly enhanced to 4.19 compared to the 92.75 of the Cu NPs film obtained under mechanical fatigue conditions over 1000 cycles and an outer bending radius of 7 mm. These results were obtained by the densification and enhanced mechanical flexibility of flash light-sintered Cu NW/NP network, which resulted in prevention of crack initiation and propagation. To characterize the Cu NW/NP ink film, X-ray diffraction and scanning electron microscopy were used.

11.
ACS Comb Sci ; 16(12): 670-7, 2014 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-25372997

RESUMO

Combinatorial high-throughput optical screening method was developed to find the optimum composition of highly active Pd-based catalysts at the cathode of the hybrid Li-air battery. Pd alone, which is one-third the cost of Pt, has difficulty in replacing Pt; therefore, the integration of other metals was investigated to improve its performance toward oxygen reduction reaction (ORR). Among the binary Pd-based catalysts, the composition of Pd-Ir derived catalysts had higher performance toward ORR compared to other Pd-based binary combinations. The composition at 88:12 at. % (Pd: Ir) showed the highest activity toward ORR at the cathode of the hybrid Li-air battery. The prepared Pd(88)Ir(12)/C catalyst showed a current density of -2.58 mA cm(-2) at 0.8 V (vs RHE), which was around 30% higher compared to that of Pd/C (-1.97 mA cm(-2)). When the prepared Pd(88)Ir(12)/C catalyst was applied to the hybrid Li-air battery, the polarization of the cell was reduced and the energy efficiency of the cell was about 30% higher than that of the cell with Pd/C.


Assuntos
Ligas/química , Técnicas de Química Combinatória/métodos , Fontes de Energia Elétrica , Eletroquímica/métodos , Eletrodos , Paládio/química , Catálise , Oxirredução , Espectroscopia Fotoeletrônica , Difração de Raios X
12.
ACS Comb Sci ; 15(11): 572-9, 2013 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-24144110

RESUMO

A combinatorial library having 66 different ternary compositions of Pd-Ir-Ce was prepared via the impregnation method to find the optimum ternary composition with the highest performance toward oxygen reduction reaction (ORR) in acid media. Its performance in ORR activity of the combinatorial array was evaluated through two different combinatorial high-throughput screening methods to gain validity: (1) multielectrode half-cell method and (2) optical screening method. From the combinatorial results, the spot at 79:12:9 for Pd-Ir-Ce (at. %) in the array showed the highest ORR activity. The electrochemical characterizations of the single catalyst demonstrates that the optimized Pd79Ir12Ce9/C catalyst shows 1.5 times the ORR activity compared to that of Pd/C catalyst at 0.85 V (vs. RHE). In the Pd-Ir-Ce based catalysts, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results reveal that Ir and Ce are present in the form of IrO2 and CeO2, respectively, and the electron configuration of Pd is effectively modified through the decoration with IrO2 and CeO2. From the results, we suggest that the electro-modification of Pd through strong metal-metal oxide interaction with IrO2-CeO2 was a reason for the enhanced ORR activity.


Assuntos
Cério/química , Técnicas de Química Combinatória , Técnicas Eletroquímicas , Irídio/química , Oxigênio/química , Paládio/química , Catálise , Oxirredução
13.
Phys Chem Chem Phys ; 15(6): 1802-5, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-23262967

RESUMO

Phosphorus and/or sulfur are additionally doped into N-doped carbon (NDC) using phosphoric acid and cysteine. The resulting catalysts demonstrate excellent oxygen reduction activities coupled with high stabilities in acidic media. Specially, additional S-doping in NDC reveals nearly 2.5 times higher activity than that of NDC at 0.75 V (vs. RHE).

14.
ACS Nano ; 6(8): 7084-91, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22769428

RESUMO

N-doped carbon, a promising alternative to Pt catalyst for oxygen reduction reactions (ORRs) in acidic media, is modified in order to increase its catalytic activity through the additional doping of B and P at the carbon growth step. This additional doping alters the electrical, physical, and morphological properties of the carbon. The B-doping reinforces the sp(2)-structure of graphite and increases the portion of pyridinic-N sites in the carbon lattice, whereas P-doping enhances the charge delocalization of the carbon atoms and produces carbon structures with many edge sites. These electrical and physical alternations of the N-doped carbon are more favorable for the reduction of the oxygen on the carbon surface. Compared with N-doped carbon, B,N-doped or P,N-doped carbon shows 1.2 or 2.1 times higher ORR activity at 0.6 V (vs RHE) in acidic media. The most active catalyst in the reaction is the ternary-doped carbon (B,P,N-doped carbon), which records -6.0 mA/mg of mass activity at 0.6 V (vs RHE), and it is 2.3 times higher than that of the N-doped carbon. These results imply that the binary or ternary doping of B and P with N into carbon induces remarkable performance enhancements, and the charge delocalization of the carbon atoms or number of edge sites of the carbon is a significant factor in deciding the oxygen reduction activity in carbon-based catalysts.


Assuntos
Boro/química , Carbono/química , Eletroquímica/métodos , Nitrogênio/química , Oxigênio/química , Fósforo/química , Teste de Materiais , Oxirredução
15.
Phys Chem Chem Phys ; 14(19): 6842-8, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22495246

RESUMO

Electrochemical properties of Pd-Mn3O4 nanoparticles toward oxygen reduction reaction (ORR) in acidic media were investigated. The catalysts were prepared by polyol reduction of Pd(acac)2 and thermal decomposition of Mn2(CO)10. Surface composition and structure of the particles vary depending on the injection temperature of Mn2(CO)10 and are closely related to the electrochemical properties. The presence of Mn3O4 promotes the performance towards ORR by facilitating oxygen transfer to the active sites of Pd. Through an accelerated degradation test (ADT), nanoparticles with a Pd-rich shell are obtained by dissolution of surface exposed Mn3O4 and at 0.57 V (vs. Ag/AgCl) this catalyst shows the highest activity towards ORR, 149% in mass activity and 142% in specific activity compared to that of Pd/C.

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