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1.
Small ; 20(2): e2305506, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37661344

RESUMO

Bilayer semiconductors have attracted much attention due to their stacking-order-dependent properties. However, as both 3R- and 2H-stacking are energetically stable at high temperatures, most of the high-temperature grown bilayer materials have random 3R- or 2H-stacking orders, leading to non-uniformity in optical and electrical properties. Here, a chemical vapor deposition method is developed to grow bilayer semiconductors with controlled stacking order by modulating the resolidified chalcogen precursors supply kinetics. Taking tungsten disulfide (WS2 ) as an example, pure 3R-stacking (100%) and 2H-stacking dominated (87.6%) bilayer WS2 are grown by using this method and both show high structural and optical quality and good uniformity. Importantly, the bilayer 3R-stacking WS2 shows higher field effect mobility than 2H-stacking samples, due to the difference in stacking order-dependent surface potentials. This method is universal for growing other bilayer semiconductors with controlled stacking orders including molybdenum disulfide and tungsten diselenide, paving the way to exploit stacking-order-dependent properties of these family of emerging bilayer materials.

2.
Nano Lett ; 23(1): 192-197, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36594477

RESUMO

The development of integrated circuits (ICs) based on a complementary metal-oxide-semiconductor through transistor scaling has reached the technology bottleneck; thus, alternative approaches from new physical mechanisms are highly demanded. Valleytronics in two-dimensional (2D) material systems has recently emerged as a strong candidate, which utilizes the valley degree of freedom to process information for electronic applications. However, for all-electrical valleytronic transistors, very low room-temperature "valley on-off" ratios (around 10) have been reported so far, which seriously limits their practical applications. In this work, we successfully illustrated both n- and p-type valleytronic transistor performances in monolayer MoS2 and WSe2 devices, with measured "valley on-off" ratios improved up to 3 orders of magnitude greater compared to previous reports. Our work shows a promising way for the electrically controllable manipulation of valley degree of freedom toward practical device applications.

3.
Am J Emerg Med ; 72: 20-26, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37453221

RESUMO

BACKGROUND: Croup caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emerging disease, and data on the risk factors associated with disease severity are still limited. The Westley croup score (WS) is widely used to assess croup severity. The current study aimed to analyze biomarkers associated with the WS and clinical outcomes in patients with croup and coronavirus disease 2019 in the pediatric emergency department (PED). POPULATION AND METHOD: Patients diagnosed with croup caused by SARS-CoV-2 were admitted at two PEDs. Clinical data including age, WS, length of hospital stay, initial laboratory data, and treatment were analyzed. Clinical parameters were evaluated via multivariate logistic regression analysis. The best cutoff values for predicting croup severity and outcomes were identified using the receiver operating characteristic curve. RESULT: In total, 250 patients were assessed. Moreover, 128 (51.2%) patients were discharged from the PED, and 122 (48.8%) were admitted to the hospital. Mild, moderate, and severe croup accounted for 63.6% (n = 159), 32% (n = 80), and 4.4% (n = 11) of all cases, respectively. A high mean age (years), neutrophil count (%), neutrophil-to-lymphocyte ratio (NLR), ALT (U/L), procalcitonin (ng/mL), and hemoglobin (g/dL) level, and length of hospital stay (days), and a low lymphocyte count (%) and blood pH were associated with croup severity and need for intensive care. Based on the multivariate logistic regression model, the NLR remained independent factors associated with croup severity and prognosis. Further, NLR was significantly correlated with WS. The area under the receiver operating characteristic curve of NLR for predicting a WS of ≥3 was 0.895 (0.842-0.948, p < 0.001), and that for predicting ICU admission was 0.795 (0.711-0.879, p < 0.001). The best cutoff values for a WS of ≥3 and ICU admission were 1.65 and 2.06, respectively. CONCLUSION: NLR is correlated with WS and is a reliable, easy-to-use, and cheap biomarker for the early screening and prognosis of croup severity in the PED. A higher NLR may indicate severe croup and the need for further treatment. And the WS score remains reliable for estimating the severity of croup caused by SARS-CoV-2 and the risk of intensive care.


Assuntos
COVID-19 , Crupe , Humanos , Criança , COVID-19/epidemiologia , COVID-19/terapia , SARS-CoV-2 , Prognóstico , Biomarcadores , Gravidade do Paciente , Linfócitos , Curva ROC , Neutrófilos , Serviço Hospitalar de Emergência , Estudos Retrospectivos
4.
Pediatr Allergy Immunol ; 33(5): e13785, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35616893

RESUMO

BACKGROUND: Several studies have reported the relevance between serum vitamin D and allergic immunoglobulin E (IgE) responses and atopic diseases. However, a metabolomics-based approach to the impacts of vitamin D on allergic reactions remains unclear. METHODS: A total of 111 children completed a 3-year follow-up were enrolled and classified based on longitudinal vitamin D status (≥ 30 ng/ml, n = 54; 20-29.9 ng/ml, n = 41; <20 ng/ml, n = 16). Urinary metabolomic profiling was performed using 1 H-Nuclear magnetic resonance (NMR) spectroscopy at age 3. Integrative analyses of their associations related to vitamin D levels, atopic indices, and allergies were performed, and their roles in functional metabolic pathways were also assessed. RESULTS: Six and five metabolites were identified to be significantly associated with vitamin D status and atopic diseases, respectively (FDR-adjusted p-value <.05). A further correlation analysis revealed that vitamin D-associated 3-hydroxyisobutyric acid and glutamine were positively correlated with atopic disease-associated succinic acid and alanine, respectively. Furthermore, hippuric acid was negatively correlated with atopic disease-associated formic acid, which was positively correlated with vitamin D level (p < .01). Absolute eosinophil count (AEC) was positively correlated with serum D. pteronyssinus- and D. farinae-specific IgE level (p < .01) but negatively correlated with vitamin D level (p < .05). Amino acid metabolisms were significantly associated with vitamin D related to childhood allergies. CONCLUSION: Integrative metabolomic analysis provides the link of vitamin D-associated metabolites with the gut microbiome and immunoallergic reactions related to childhood allergies.


Assuntos
Asma , Hipersensibilidade , Animais , Criança , Pré-Escolar , Dermatophagoides farinae , Humanos , Hipersensibilidade/epidemiologia , Imunoglobulina E , Metabolômica/métodos , Vitamina D
5.
Pediatr Allergy Immunol ; 32(8): 1673-1680, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34176158

RESUMO

BACKGROUND: Dysregulation of eicosanoids is associated with asthma and a composite of oxylipins, including exhaled leukotriene B4 (LTB4 ), characterizes childhood asthma. While fractional exhaled nitric oxide (FeNO) has been used as the standard for monitoring steroid responsiveness, the potential utility of eicosanoids in monitoring the therapeutic outcomes remains unclear. We aimed to examine the levels of major eicosanoids representing different metabolic pathways in exhaled breath condensates (EBCs) of children with asthma during exacerbation and after treatment. METHODS: Levels of 6 exhaled eicosanoid species in asthmatic children and healthy subjects were evaluated using ELISA. RESULTS: In addition to those previously reported, including LTB4 , the levels of exhaled 15-hydroxyeicosatetraenoic acid (15-HETE), but not thromboxane B2 (TXB2 ), showed significant difference between asthmatics (N = 318) and healthy controls (N = 97), particularly the severe group showed the lowest levels of exhaled 15-HETE. Receiver operating characteristic (ROC) curve analyses revealed similar distinguishing power for the levels of 15-HETE, FEV1 (forced expiratory volume in the first second), and FeNO, while the 15-HETE/LTB4 ratio was significantly lower in subjects with asthma as compared to that of healthy controls (p < 0.0001). Analysis of asthmatics (N = 75) during exacerbation and convalescence showed significant improvement in lung function (FEV1 , p < .001), but not FeNO, concomitant with significantly increased levels of 15-HETE (p < .001) and reduced levels of TXB2 (p < .05) at convalescence, particularly for those who at the top 30% level during exacerbation. Further, decreased LTB4 and lipoxin A4 (LXA4 ) at convalescence were noted only in those at the top 30 percentile during exacerbation. CONCLUSION: The exhaled 15-HETE was found to discriminate childhood asthma while decreased levels of exhaled TXB2 and increased levels of 15-HETE were prominent at convalescence.


Assuntos
Asma , Teste da Fração de Óxido Nítrico Exalado , Asma/diagnóstico , Asma/tratamento farmacológico , Testes Respiratórios , Criança , Volume Expiratório Forçado , Humanos , Ácidos Hidroxieicosatetraenoicos , Óxido Nítrico , Resultado do Tratamento
6.
Environ Res ; 191: 110123, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32905812

RESUMO

BACKGROUND: Reports on the relationship between prenatal exposure to bisphenol-A (BPA) and the development of childhood allergy have been conflicting. This study aimed to investigate the impact of prenatal BPA exposure on several objective outcomes such as cytokine profile, atopic sensitization, and infant lung function (ILF) tests in addition to clinical allergic symptoms. METHODS: A subset of 274 children from the PATCH cohort study with available cord BPA data were followed until 3 years of age. Total and specific IgE level and Toll-like receptor (TLR) stimulated cytokine production were assessed yearly since birth. ILF such as tidal volume, VmaxFRC, airway resistance and compliance were performed at least once before the age of 2 years. Allergic outcome was determined by questionnaires and physician's assessment. RESULTS: There was significant association between BPA concentration and IgE level in the cord blood (p < 0.01), but the correlation was no longer significant at ages 1 through 3 years. In addition, cord BPA concentration was associated with dysregulated TLR stimulated TNF-α and IL-6 production, but the correlation was significant only at birth. No relationship was found between cord BPA concentration and ILF measurements or allergic symptoms (wheezing, rhino-conjunctivitis, or eczema) throughout early childhood. CONCLUSION: Results showed that prenatal exposure to BPA was not associated with increased risk of childhood allergy or impaired ILF. However, with its impact on biomarkers for allergy such as alterations in perinatal cytokine profile and elevated cord IgE level, the potential role of prenatal BPA exposure on the development of allergy cannot be disregarded.


Assuntos
Hipersensibilidade , Efeitos Tardios da Exposição Pré-Natal , Compostos Benzidrílicos/toxicidade , Criança , Pré-Escolar , Estudos de Coortes , Citocinas , Feminino , Humanos , Hipersensibilidade/epidemiologia , Hipersensibilidade/etiologia , Imunoglobulina E , Lactente , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente
7.
J Proteome Res ; 18(3): 1248-1254, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30757903

RESUMO

Fibrin formation in infectious parapneumonic effusion (IPE) characterizes complicated parapneumonic effusion and is important for providing guidelines for the management of IPEs that require aggressive interventions. We aim to identify metabolic mechanisms associated with bacterial invasion, inflammatory cytokines, and biochemical markers in cases of fibrinous infectious pleural effusions in children with pneumonia. Pleural fluid metabolites were determined by 1H nuclear magnetic resonance spectroscopy. Metabolites that contributed to the separation between fibrinous and nonfibrinous IPEs were identified using supervised partial least squares discriminant analysis ( Q2/ R2 = 0.84; Ppermutation < 0.01). IL-1ß in the inflammatory cytokines and glucose in the biochemical markers were significantly correlated with 11 and 9 pleural fluid metabolites, respectively, and exhibited significant overlaps. Four metabolites, including glucose, lactic acid, 3-hydroxybutyric acid, and hypoxanthine, were significantly correlated with plasminogen activator inhibitor type 1 in the fibrinolytic system enzymes. Metabolic pathway analysis revealed that anaerobic bacterial fermentation with increased lactic acid and butyric acid via glucose consumption and adenosine triphosphate hydrolysis with increased hypoxanthine appeared to be associated with fibrinous IPE. Our results demonstrate that an increase in lactic acid anaerobic fermentation and hypoxanthine accumulation under hypoxic conditions are associated with fibrin formation in IPE, representing advanced pleural inflammatory progress in children with pneumonia.


Assuntos
Fibrina/metabolismo , Hipoxantina/metabolismo , Pulmão/diagnóstico por imagem , Derrame Pleural/metabolismo , Pneumonia/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Adolescente , Anaerobiose/genética , Bactérias Anaeróbias/metabolismo , Bactérias Anaeróbias/patogenicidade , Criança , Pré-Escolar , Citocinas/genética , Citocinas/metabolismo , Feminino , Fermentação , Fibrina/genética , Fibrinólise/genética , Glucose/metabolismo , Humanos , Lactente , Ácido Láctico/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Masculino , Metabolômica/métodos , Derrame Pleural/microbiologia , Derrame Pleural/patologia , Pneumonia/diagnóstico por imagem , Pneumonia/microbiologia , Pneumonia/patologia
8.
Pediatr Allergy Immunol ; 30(2): 204-213, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30561094

RESUMO

BACKGROUND: This study aimed to investigate whether maternal allergy is associated with soluble CD14 (sCD14) and fatty acid composition in different stages of lactation and the onset of atopic dermatitis (AD) in early childhood. METHODS: In total, 443 mother-child groups (445 children) were enrolled in the Prediction of Allergies in Taiwanese Children birth cohort study. Colostrum and mature milk at 2 months postpartum (2-month HM) were collected from lactating mothers. Information regarding parental allergy histories and physician-diagnosed atopic diseases was obtained using age-specific questionnaires (0-2 years). We compared sCD14 levels and the composition of 30 fatty acids in the colostrum and 2-month HM, respectively, between allergic and non-allergic mothers and between children with and without AD by the age of 2 years. RESULTS: In total, 185 (41.8%) mothers presented with allergies, and 154 (34.6%) children had physician-diagnosed AD by the age of 2 years. Both in the colostrum and 2-month HM of 289 lactating mothers, sCD14 levels were significantly lower in allergic mothers whose children presented with AD compared with children who did not (P = 0.015 and 0.044, respectively). Among the children with AD who were born to non-allergic mothers, sCD14 levels were lower. However, the result was not statistically significant (P = 0.376 and 0.264, respectively). Our data revealed the lack of associations between fatty acid composition and AD (P > 0.05). CONCLUSION: Decreased sCD14 levels in the colostrum and 2-month HM were associated with AD at 2 years of age, particularly among children born to mothers with allergies.


Assuntos
Dermatite Atópica/etiologia , Ácidos Graxos/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Leite Humano/metabolismo , Efeitos Tardios da Exposição Pré-Natal/imunologia , Pré-Escolar , Estudos de Coortes , Colostro/imunologia , Colostro/metabolismo , Dermatite Atópica/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Lactação , Masculino , Leite Humano/imunologia , Mães , Gravidez , Inquéritos e Questionários , Taiwan
9.
Pediatr Allergy Immunol ; 29(3): 254-259, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29240264

RESUMO

BACKGROUND: There are few studies addressing the longitudinal analysis of vitamin D deficiency and its impact on the development of atopic diseases in early childhood. METHODS: We investigated 155 children who regularly followed up at our clinic for 5 years as subjects enrolled in a birth cohort study. The pattern of vitamin D levels from birth to 5 years of age was clustered using K-means method in R software. Absolute eosinophil count (AEC), and total serum and specific immunoglobulin E antibodies against food (egg white, milk, and wheat) and inhalant allergens (Dermatophagoides pteronyssinus, Dermatophagoides farina, and Cladosporium herbarum) were measured at 1.5, 3, 4 and 5 years of age. RESULTS: A total of 137 children with serum samples obtained over at least 3 time points during the follow-up period were recruited. Using K-means clustering, the dynamic changes in vitamin D levels were significantly stratified into 3 clusters (cluster A, ≥30 ng/mL, n = 61; cluster B, 20-29.9 ng/mL, n = 53; cluster C, <20 ng/mL, n = 23). Despite no statistical association with atopic diseases, a persistent vitamin D deficiency appeared to be associated with eosinophilia at age 3, and total serum and mite-specific immunoglobulin E (IgE) levels at age 4. Furthermore, an associated higher prevalence of mite sensitization at age 4 was significantly associated with the risk of allergic rhinitis and asthma. CONCLUSIONS: Vitamin D deficiency is inversely associated with AEC and mite-specific IgE levels, which may potentially increase susceptibility to develop allergies including rhinitis and asthma in early childhood.


Assuntos
Hipersensibilidade/etiologia , Ácaros/imunologia , Deficiência de Vitamina D/complicações , Vitamina D/sangue , Alérgenos/imunologia , Animais , Pré-Escolar , Estudos de Coortes , Eosinofilia/etiologia , Eosinofilia/imunologia , Feminino , Humanos , Hipersensibilidade/epidemiologia , Imunoglobulina E/sangue , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Prevalência , Taiwan/epidemiologia
10.
Pediatr Allergy Immunol ; 29(5): 496-503, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29679407

RESUMO

BACKGROUND: Several metabolites and altered metabolic pathways have been reported to be associated with asthma. However, longitudinal analysis of the dynamics of metabolites contributing to the development of asthma has not yet been fully clarified. METHODS: We sought to identify the metabolic mechanisms underlying asthma development in early childhood. Thirty children with asthma and paired healthy controls from a prospective birth cohort were enrolled. Time series analysis of urinary metabolites collected at ages 1, 2, 3, and 4 years was assessed using 1 H nuclear magnetic resonance (NMR) spectroscopy coupled with partial least squares discriminant analysis (PLS-DA). Metabolites identified were studied in relation to changes over time in a linear mixed model for repeated measures. RESULTS: A total of 172 urine samples collected from the enrolled children were analyzed. Urinary metabolomics identified four metabolites significantly associated with childhood asthma development, with longitudinal analysis. Among them, dimethylamine, a metabolite produced by intestinal bacteria, appeared to shift from higher to lower level during asthma development. A persistent lower level of 1-methylnicotinamide and allantoin was found in children with asthma, with a peak difference at age 3 years (P = .032 and P = .021, respectively). Furthermore, a significant inverse correlation was found between allantoin and house dust mite sensitization (Spearman's r = -.297 P = .035). CONCLUSIONS: Longitudinal urinary metabolomic profiling provides a link of microbe-environment interactions in the development of childhood asthma. 1-Methylnicotinamide and allantoin may participate in allergic reactions in response to allergen exposure, potentially serving as specific biomarkers for asthma.


Assuntos
Asma/imunologia , Hipersensibilidade/imunologia , Metabolômica/métodos , Alantoína/urina , Animais , Antígenos de Dermatophagoides/imunologia , Biomarcadores/urina , Estudos de Casos e Controles , Pré-Escolar , Estudos de Coortes , Dimetilaminas/urina , Feminino , Microbioma Gastrointestinal , Humanos , Lactente , Estudos Longitudinais , Espectroscopia de Ressonância Magnética , Masculino , Estudos Prospectivos , Pyroglyphidae/imunologia
11.
Phys Chem Chem Phys ; 20(3): 1447-1459, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29255815

RESUMO

Garnet-type cubic Li7La3Zr2O12 exhibits one of the highest lithium-ion conductivity values amongst oxides (up to ∼2 mS cm-1 at room temperature). This compound has also emerged as a promising candidate for solid electrolytes in all-solid-state lithium batteries, due to its high ionic conductivity, good chemical stability against lithium metal, and wide electrochemical stability window. Defect chemistry of this class of materials, although less studied, is critical to the understanding of the nature of ionic conductivity and predicting the properties of grain boundaries and heterogeneous solid interfaces. In this study, the electrical properties of nominally undoped cubic Li7La3Zr2O12 are characterized as a function of temperature and pO2 using a suite of AC impedance and DC polarization techniques. The formation of ionic defects and defect pairs as well as their impact on the transport properties are discussed, and a Brouwer-type diagram is constructed.

12.
Pediatr Res ; 82(5): 733-740, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29040259

RESUMO

BackgroundIn this study, we aimed to determine whether introducing various allergenic foods during infancy is associated with IgE sensitization at 12 months of age.MethodsDetailed information on feeding practices regarding six possible allergenic foods (fruits, egg white, egg yolk, fish, shellfish, and peanuts) was obtained by administering age-specific questionnaires to parents of infants at ages 6 and 12 months. Fecal secretory IgA (sIgA), fecal eosinophil cationic protein (ECP), and serum levels of total IgE and IgE specific to 20 foods, and IgE specific to 20 inhalant allergens were also quantified at 12 months of age.ResultsAt 12 months of age, infants with IgE sensitization had been introduced to fewer allergenic food items during infancy (3.2±1.4 vs. 3.7±1.3 items). Compared with infants who were given 0-2 allergenic food items, infants introduced to 3-4 or ≥5 allergenic food items showed a significantly lower risk of IgE sensitization (odds ratios (ORs) 0.62 and 0.61, respectively) and lower total IgE levels. In addition, non-introduction of egg white or egg yolk was significantly related to IgE sensitization (ORs 1.41 and 1.26, respectively).ConclusionIncreasing the diversity of allergenic foods in infancy, including fruits, egg white, egg yolk, fish, shellfish, and peanuts, may protect infants from IgE sensitization at 12 months of age.


Assuntos
Alérgenos/administração & dosagem , Dieta , Métodos de Alimentação , Hipersensibilidade Alimentar/prevenção & controle , Imunoglobulina E/sangue , Alimentos Infantis , Administração por Inalação , Fatores Etários , Alérgenos/efeitos adversos , Alérgenos/imunologia , Biomarcadores/sangue , Dieta/efeitos adversos , Proteínas Dietéticas do Ovo/administração & dosagem , Proteínas Dietéticas do Ovo/efeitos adversos , Proteínas Dietéticas do Ovo/imunologia , Fezes/química , Feminino , Hipersensibilidade Alimentar/sangue , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Frutas/efeitos adversos , Frutas/imunologia , Humanos , Imunoglobulina A Secretora/sangue , Lactente , Alimentos Infantis/efeitos adversos , Masculino , Razão de Chances , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/prevenção & controle , Fatores de Risco , Hipersensibilidade a Frutos do Mar/diagnóstico , Hipersensibilidade a Frutos do Mar/imunologia , Hipersensibilidade a Frutos do Mar/prevenção & controle
13.
J Electrochem Soc ; 164(8): H5189-H5196, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30034028

RESUMO

A comprehensive variable temperature, pressure and frequency multinuclear (1H, 2H, and 19F) magnetic resonance study was undertaken on selectively deuterated 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide (BMIM TFSA) ionic liquid isotopologues. This study builds on our earlier investigation of the effects of increasing alkyl chain length on diffusion and dynamics in imidazolium-based TFSA ionic liquids. Fast field cycling 1H T1 data revealed multiple modes of motion. Through calculation of diffusion coefficient (D) values and activation energies, the low- and high-field regimes were assigned to the translational and reorientation dynamics respectively. Variable-pressure 2H T1 measurements reveal site-dependent interactions in the cation with strengths in the order MD3 > CD3 > CD2, indicating dissimilarities in the electric field gradients along the alkyl chain, with the CD2 sites having the largest gradient. Additionally, the α saturation effect in T1 vs. P was observed for all three sites, suggesting significant reduction of the short-range rapid reorientational dynamics. This reduction was also deduced from the variable pressure 1H T1 data, which showed an approach to saturation for both the methyl and butyl group terminal methyl sites. Pressure-dependent D measurements show independent motions for both cations and anions, with the cations having greater D values over the entire pressure range.

14.
Pediatr Res ; 79(3): 438-44, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26571221

RESUMO

BACKGROUND: Despite widespread human exposure to biphenol A (BPA), limited studies exist on the association of BPA with adverse health outcomes in young children. This study aims to investigate the effect of prenatal exposure to BPA on toll-like receptor-induced cytokine responses in neonates and its association with infectious diseases later in life. METHODS: Cord bloods were collected from 275 full-term neonates. Production of TNF-α, IL-6, and IL-10 were evaluated after stimulating mononuclear cells with toll-like receptor ligands (TLR1-4 and 7-8). Serum BPA concentrations were analyzed by enzyme-linked immunosorbent assay. Bacteria from nasopharyngeal specimens were identified with multiplex PCR and culture method. RESULT: Result showed significant association between cord BPA concentration and TLR3- and TLR4-stimulated TNF-α response (P = 0.001) and that of TLR78-stimulated IL-6 response (P = 0.03). Clinical analysis did not show prenatal BPA exposure to be correlated with infection or bacterial colonization during the first year of life. CONCLUSION: This is the first cohort study that indicated prenatal BPA exposure to play a part in TLR-related innate immune response of neonatal infants. However, despite an altered immune homeostasis, result did not show such exposure to be associated with increased risk of infection during early infancy.


Assuntos
Compostos Benzidrílicos/efeitos adversos , Citocinas/antagonistas & inibidores , Fenóis/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Receptores Toll-Like/metabolismo , Fatores Etários , Estudos de Coortes , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Sangue Fetal/citologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Interleucina-10/sangue , Interleucina-6/sangue , Leucócitos Mononucleares/citologia , Ligantes , Masculino , Exposição Materna , Nasofaringe/microbiologia , Razão de Chances , Gravidez , Análise de Regressão , Risco , Receptores Toll-Like/sangue , Receptores Toll-Like/imunologia , Fator de Necrose Tumoral alfa/sangue
15.
Mediators Inflamm ; 2016: 8175898, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27298518

RESUMO

Reports on the effect of prenatal vitamin D status on fetal immune development and infectious diseases in childhood are limited. The aim of this study was to investigate the role of maternal and cord blood vitamin D level in TLR-related innate immunity and its effect on infectious outcome. Maternal and cord blood 25 (OH)D level were examined from 372 maternal-neonatal pairs and their correlation with TLR-triggered TNF-α, IL-6, and IL-10 response at birth was assessed. Clinical outcomes related to infection at 12 months of age were also evaluated. The result showed that 75% of the pregnant mothers and 75.8% of the neonates were vitamin deficient. There was a high correlation between maternal and cord 25(OH)D levels (r = 0.67, p < 0.001). Maternal vitamin D level was inversely correlated with IL-10 response to TLR3 (p = 0.004) and TLR7-8 stimulation (p = 0.006). However, none of the TLR-triggered cytokine productions were associated with cord 25(OH)D concentration. There was no relationship between maternal and cord blood vitamin D status with infectious diseases during infancy. In conclusion, our study had shown that maternal vitamin D, but not cord vitamin D level, was associated with viral TLR-triggered IL-10 response.


Assuntos
Doenças Transmissíveis/sangue , Interleucina-10/sangue , Receptores Toll-Like/sangue , Vitamina D/sangue , Adulto , Estudos de Coortes , Meios de Cultura/metabolismo , Feminino , Sangue Fetal/metabolismo , Humanos , Interleucina-6/sangue , Ligantes , Masculino , Monócitos/citologia , Gravidez , Estudos Prospectivos , Fator de Necrose Tumoral alfa/sangue , Vírus/metabolismo
16.
J Pediatr ; 165(6): 1098-1103.e1, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25282066

RESUMO

OBJECTIVE: To investigate the relationship of vitamin D status with lung function and fraction of exhaled nitric oxide (FeNO) in a population sample of children. STUDY DESIGN: A total of 1315 children aged 5-18 years were evaluated using serum 25-hydroxyvitamin D [25(OH)D] levels, spirometry, a single-breath online FeNO measurement, and questionnaires. RESULTS: After adjusting for confounders, the mean forced vital capacity was 53.4 mL (SE, 26.5 mL; P = .045), and the mean forced expiratory volume in 1 second was 48.2 mL (SE, 23.6 mL; P = .042) lower for children with insufficient serum 25(OH)D levels (20-29.9 ng/mL) compared with those with sufficient 25(OH)D levels (≥30 ng/mL). The mean difference between children with deficient (<20 ng/mL) and sufficient levels of serum 25(OH)D was 81.9 mL (SE, 26.7 mL; P = .002) for forced vital capacity and 55.2 mL (SE, 23.7 mL; P = .020) for forced expiratory volume in 1 second. There was no significant association between serum 25(OH)D levels and FeNO after adjusting for confounders. CONCLUSIONS: Our results demonstrate a significant relationship between insufficient serum vitamin D levels and worse lung function in children in the community with a suggested dose-response effect. Our findings also suggest that vitamin D status is not a significant determinant of FeNO in children in the general population.


Assuntos
Testes Respiratórios , Pulmão/fisiologia , Óxido Nítrico/análise , Vitamina D/análogos & derivados , Adolescente , Testes Respiratórios/métodos , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Análise Multivariada , Análise de Regressão , Capacidade Vital , Vitamina D/sangue , Vitamina D/fisiologia , Adulto Jovem
18.
Pediatr Allergy Immunol ; 25(5): 456-61, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25171739

RESUMO

BACKGROUND: Although breastfed infants have consistently been reported as having fewer infections and respiratory morbidity during infancy, none have reached a definitive conclusion as to whether breastfeeding is an effective strategy to prevent allergic diseases. This study aims to investigate the relationship between exclusive breastfeeding and sequential changes of several biomarkers of allergy, such as absolute eosinophil count, total IgE level, and specific IgE level during the first 3 yrs of life. METHODS: This is an unselected, population-based study that is part of a prospective birth cohort called the PATCH (Prediction of Allergy in Taiwanese Children). Blood analysis was performed at ages 6, 12, 18, 24, and 36 months. Clinical records of breastfeeding and detailed questionnaires regarding to allergic diseases were also obtained. RESULTS: Analysis comparing exclusive breastfeeding ≥4 months with those <4 months and those partially breastfed showed a decreased risk of sensitization toward cow's milk protein up to the age of 2 yr (adjusted OR for cow's milk sensitization at 12 months was 0.2 [95% CI, 0.07-0.5]), at 18 months of age it was 0.2 [95% CI, 0.07-0.5], and at 24 months of age it was 0.2 [95% CI, 0.04-0.7]). In addition, although not significant, children of the exclusive breastfeeding group showed a trend of lower absolute eosinophil counts than their counterparts at all ages, and a lower total IgE level at the age of 3 yr. CONCLUSIONS: Results of this study suggest that exclusive breastfeeding is associated with a reduced risk of cow's milk protein sensitization during early childhood.


Assuntos
Aleitamento Materno , Hipersensibilidade a Leite/epidemiologia , Animais , Bovinos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Leite/efeitos adversos , Leite/imunologia , Hipersensibilidade a Leite/imunologia
19.
Pediatr Hematol Oncol ; 31(1): 87-94, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24383988

RESUMO

G6PD-deficient adults are reported to be susceptible to severe infection, and decreased cytokine responses have been postulated as the underlying mechanism. However, investigating the association of G6PD deficiency and cytokine responses during infancy is lacking. The current study aims to determine whether cytokine responses of tumor necrosis factor ()-α, interleukins (IL)-6, and IL-10 are impaired in the G6PD-deficient infants. Upon agreements with informed consents, peripheral blood mononuclear cells (PBMCs) of enrolled infants were collected twice at 1 month and 1 year of age. PBMCs were then stimulated with toll-like receptor (TLR) agonists-including PAM3csk4 for TLR1-2, poly (I:C) for TLR3, and lipopolysaccharide for TLR4-to analyze the expression of TNF-α, IL-6, and IL-10. Males (P = .004) and phototherapy during neonatal period (P = .008) were more common among G6PD-deficient infants than G6PD-normal subjects. After the stimulation of TLR agonists, there was no significant difference in the expression of TNF-α, IL-6, and IL-10 between PBMCs of G6PD-deficient and -normal infants at both 1 month and 1 year of age. In conclusion, the clinical characteristics of G6PD-deficient infants are different from those of G6PD-normal subjects. The data suggest that the innate immune responses to TLR agonists in G6PD-deficient infants are not different from those of G6PD-normal infants.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/imunologia , Interleucina-10/sangue , Interleucina-6/sangue , Fator de Necrose Tumoral alfa/análise , Células Cultivadas , Suscetibilidade a Doenças , Seguimentos , Deficiência de Glucosefosfato Desidrogenase/sangue , Deficiência de Glucosefosfato Desidrogenase/complicações , Humanos , Hiperbilirrubinemia/etiologia , Hiperbilirrubinemia/radioterapia , Lactente , Recém-Nascido , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Fototerapia , Receptores Toll-Like/agonistas , Fator de Necrose Tumoral alfa/metabolismo
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(3): 630-3, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-25208379

RESUMO

The Sb2O4:Yb3+, Tm3+ up-conversion luminescence powder with excellent physical, chemical stability and relative low phonon energy was synthesized by the high temperature solid-state reaction and its up-conversion luminescence property was investigated. Under the 980 nm excitation, infrared and blue up-conversion emissions centered at 800 and 480 nm were observed, which were assigned to the 1G4-->3H6 and 3H4-->3 He transitions of Tm2+, respectively. The influence of Yb3+ and Tm3+ concentration on the up-conversion emission property was also obtained. The up-conversion luminescence increases with increasing of Yb3+ and Tm3+ concentration. Additionally, the up-conversion luminescence mechanism was discussed based on the dependence of Tm3+ up-conversion luminescence on pump power. It is interesting that two photon excitation processes for blue and infrared emission were observed in the Sb2O04: Yb3+, Tm3+ powder under a 980 nm excitation. Based on the energy level diagram of Tma3 and Yb2+ ions, we think that two photons blue emission is contributed to the cooperation energy transfer between Tm"+ and Yb3+ ions. We believe that the Sbz04 : Yb3 , Tm2+ up-conversion luminescence powder will have potential application for new optical devices in up-conversion color displays, sensors, detection of infrared radiation, and lasers.

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