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1.
Nat Mater ; 22(8): 992-998, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37365226

RESUMO

Conventional antiferroelectric materials with atomic-scale anti-aligned dipoles undergo a transition to a ferroelectric (FE) phase under strong electric fields. The moiré superlattice formed in the twisted stacks of van der Waals crystals exhibits polar domains alternating in moiré length with anti-aligned dipoles. In this moiré domain antiferroelectic (MDAF) arrangement, the distribution of electric dipoles is distinguished from that of two-dimensional FEs, suggesting dissimilar domain dynamics. Here we performed an operando transmission electron microscopy investigation on twisted bilayer WSe2 to observe the polar domain dynamics in real time. We find that the topological protection, provided by the domain wall network, prevents the MDAF-to-FE transition. As one decreases the twist angle, however, this transition occurs as the domain wall network disappears. Exploiting stroboscopic operando transmission electron microscopy on the FE phase, we measure a maximum domain wall velocity of 300 µm s-1. Domain wall pinnings by various disorders limit the domain wall velocity and cause Barkhausen noises in the polarization hysteresis loop. Atomic-scale analysis of the pinning disorders provides structural insight on how to improve the switching speed of van der Waals FEs.

2.
Diabetologia ; 66(5): 931-954, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36759348

RESUMO

AIMS/HYPOTHESIS: Non-alcoholic fatty liver disease (NAFLD) associated with type 2 diabetes may more easily progress towards severe forms of non-alcoholic steatohepatitis (NASH) and cirrhosis. Although the Wnt effector transcription factor 7-like 2 (TCF7L2) is closely associated with type 2 diabetes risk, the role of TCF7L2 in NAFLD development remains unclear. Here, we investigated how changes in TCF7L2 expression in the liver affects hepatic lipid metabolism based on the major risk factors of NAFLD development. METHODS: Tcf7l2 was selectively ablated in the liver of C57BL/6N mice by inducing the albumin (Alb) promoter to recombine Tcf7l2 alleles floxed at exon 5 (liver-specific Tcf7l2-knockout [KO] mice: Alb-Cre;Tcf7l2f/f). Alb-Cre;Tcf7l2f/f and their wild-type (Tcf7l2f/f) littermates were fed a high-fat diet (HFD) or a high-carbohydrate diet (HCD) for 22 weeks to reproduce NAFLD/NASH. Mice were refed a standard chow diet or an HCD to stimulate de novo lipogenesis (DNL) or fed an HFD to provide exogenous fatty acids. We analysed glucose and insulin sensitivity, metabolic respiration, mRNA expression profiles, hepatic triglyceride (TG), hepatic DNL, selected hepatic metabolites, selected plasma metabolites and liver histology. RESULTS: Alb-Cre;Tcf7l2f/f essentially exhibited increased lipogenic genes, but there were no changes in hepatic lipid content in mice fed a normal chow diet. However, following 22 weeks of diet-induced NAFLD/NASH conditions, liver steatosis was exacerbated owing to preferential metabolism of carbohydrate over fat. Indeed, hepatic Tcf7l2 deficiency enhanced liver lipid content in a manner that was dependent on the duration and amount of exposure to carbohydrates, owing to cell-autonomous increases in hepatic DNL. Mechanistically, TCF7L2 regulated the transcriptional activity of Mlxipl (also known as ChREBP) by modulating O-GlcNAcylation and protein content of carbohydrate response element binding protein (ChREBP), and targeted Srebf1 (also called SREBP1) via miRNA (miR)-33-5p in hepatocytes. Eventually, restoring TCF7L2 expression at the physiological level in the liver of Alb-Cre;Tcf7l2f/f mice alleviated liver steatosis without altering body composition under both acute and chronic HCD conditions. CONCLUSIONS/INTERPRETATION: In mice, loss of hepatic Tcf7l2 contributes to liver steatosis by inducing preferential metabolism of carbohydrates via DNL activation. Therefore, TCF7L2 could be a promising regulator of the NAFLD associated with high-carbohydrate diets and diabetes since TCF7L2 deficiency may lead to development of NAFLD by promoting utilisation of excess glucose pools through activating DNL. DATA AVAILABILITY: RNA-sequencing data have been deposited into the NCBI GEO under the accession number GSE162449 ( www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE162449 ).


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Lipogênese/genética , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Hepatócitos/metabolismo , Dieta Hiperlipídica , Triglicerídeos/metabolismo , Glucose/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo
3.
Allergy ; 78(5): 1292-1306, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36609802

RESUMO

BACKGROUND: Staphylococcus (S) aureus colonization is known to cause skin barrier disruption in atopic dermatitis (AD) patients. However, it has not been studied how S. aureus induces aberrant epidermal lipid composition and skin barrier dysfunction. METHODS: Skin tape strips (STS) and swabs were obtained from 24 children with AD (6.0 ± 4.4 years) and 16 healthy children (7.0 ± 4.5 years). Lipidomic analysis of STS samples was performed by mass spectrometry. Skin levels of methicillin-sensitive and methicillin-resistant S. aureus (MSSA and MRSA) were evaluated. The effects of MSSA and MRSA were evaluated in primary human keratinocytes (HEKs) and organotypic skin cultures. RESULTS: AD and organotypic skin colonized with MRSA significantly increased the proportion of lipid species with nonhydroxy fatty acid sphingosine ceramide with palmitic acid ([N-16:0 NS-CER], sphingomyelins [16:0-18:0 SM]), and lysophosphatidylcholines [16:0-18:0 LPC], but significantly reduced the proportion of corresponding very long-chain fatty acids (VLCFAs) species (C22-28) compared to the skin without S. aureus colonization. Significantly increased transepidermal water loss (TEWL) was found in MRSA-colonized AD skin. S. aureus indirectly through interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-6, and IL-33 inhibited expression of fatty acid elongase enzymes (ELOVL3 and ELOVL4) in HEKs. ELOVL inhibition was more pronounced by MRSA and resulted in TEWL increase in organotypic skin. CONCLUSION: Aberrant skin lipid profiles and barrier dysfunction are associated with S. aureus colonization in AD patients. These effects are attributed to the inhibition of ELOVLs by S. aureus-induced IL-1ß, TNF-α, IL-6, and IL-33 seen in keratinocyte models and are more prominent in MRSA than MSSA.


Assuntos
Dermatite Atópica , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Criança , Humanos , Staphylococcus aureus , Interleucina-33/farmacologia , Interleucina-6 , Dermatite Atópica/patologia , Lipídeos
4.
Small ; 18(8): e2105492, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34889031

RESUMO

Isotropic InP/ZnSe/ZnS quantum dots (QDs) are prepared at a high reaction temperature, which facilitates ZnSe shell growth on random facets of the InP core. Fast crystal growth enables stacking faults elimination, which induces anisotropic growth, and as a result, improves the photoluminescence (PL) quantum yield by nearly 20%. Herein, the effect of the QD morphology on photophysical properties is investigated by observing the PL blinking and ultrafast charge carrier dynamics. It is found that hot hole trapping is considerably suppressed in isotropic InP QDs, indicating that the stacking faults in the anisotropic InP/ZnSe structures act as defects for luminescence. These results highlight the importance of understanding the correlation between QD shapes and hot carrier dynamics, and present a way to design highly luminescent QDs for further promising display applications.

5.
Int J Mol Sci ; 22(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925827

RESUMO

Liver disease is the spectrum of liver damage ranging from simple steatosis called as nonalcoholic fatty liver disease (NAFLD) to hepatocellular carcinoma (HCC). Clinically, NAFLD and type 2 diabetes coexist. Type 2 diabetes contributes to biological processes driving the severity of NAFLD, the primary cause for development of chronic liver diseases. In the last 20 years, the rate of non-viral NAFLD/NASH-derived HCC has been increasing rapidly. As there are currently no suitable drugs for treatment of NAFLD and NASH, a class of thiazolidinediones (TZDs) drugs for the treatment of type 2 diabetes is sometimes used to improve liver failure despite the risk of side effects. Therefore, diagnosis, prevention, and treatment of the development and progression of NAFLD and NASH are important issues. In this review, we will discuss the pathogenesis of NAFLD/NASH and NAFLD/NASH-derived HCC and the current promising pharmacological therapies of NAFLD/NASH. Further, we will provide insights into "adipose-derived adipokines" and "liver-derived hepatokines" as diagnostic and therapeutic targets from NAFLD to HCC.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica , Obesidade/complicações , Adipocinas/metabolismo , Carcinoma Hepatocelular/fisiopatologia , Diabetes Mellitus Tipo 2/metabolismo , Progressão da Doença , Humanos , Fígado/metabolismo , Cirrose Hepática/fisiopatologia , Falência Hepática , Neoplasias Hepáticas/fisiopatologia , Síndrome Metabólica/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo
6.
Nanotechnology ; 31(18): 185503, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945750

RESUMO

Biopolymer adsorption onto a membrane is a significant issue in the reliability of solid-state nanopore devices, since it degrades the device performance or promotes device failure. In this work, a poly(ethylene glycol) (PEG) layer was coated on a silicon nitride (SiNx) membrane by plasma-polymerized vapor deposition to inhibit biopolymer adsorption. From optical observations, the deposited PEG layer demonstrated increased hydrophilicity and anti-adsorption property compared to the SiNx surface. Electrical properties of the PEG/SiNx nanopore were characterized, showing Ohmic behavior and a 6.3 times higher flicker noise power due to the flexible conformation of PEG in water. Antifouling performance of each surface was analyzed by measuring the average time from voltage bias to the first adsorption during DNA translocation experiments, where the modified surface enabled two times prolonged device operation. The time to adsorption was dependent on the applied voltage, implying adsorption probability was dominated by the electrophoretic DNA approach to the nanopore. DNA translocation behaviors on each surface were identified from translocation signals, as the PEG layer promoted unfolded and fast movement of DNA through the nanopore. This work successfully analyzed the effect of the PEG layer on DNA adsorption and translocation in solid-state nanopore experiments.

7.
Nanotechnology ; 31(9): 095708, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31747645

RESUMO

A graphene/In2O3 bilayer (termed as GI-bilayer) is proposed as a transparent conducting electrode with remarkably improved areal-uniformity. To fabricate this new structure, an In2O3 layer with a thickness of less than 50 nm was grown by atomic layer deposition and then a graphene layer was grown by chemical vapor deposition and subsequently transferred onto the as-grown In2O3 layer. Electrical and optical properties of the GI-bilayer were systematically studied to verify effects of the underlying In2O3 layer. Hall measurements and following analysis showed a conductance enhancement of the GI-bilayer owing to p-type doping of graphene. Specifically, Raman analysis and ultraviolet photoelectron spectroscopy were performed to prove p-type doping of the graphene in the GI-bilayer. In addition, the GI-bilayer exhibited the significantly improved uniformity of the sheet resistance compared to that of a conventional monolayer of graphene. There was a duality on the role of the In2O3 underlayer in the GI-bilayer. It acted as a dopant layer to the graphene and lowered the sheet resistance from 863 to 510 Ω/sq as well as compensated microscale defects on graphene. More importantly, the In2O3 underlayer resulted in the extremely reduced standard deviation of sheet resistance from 150 to 7.5 Ω/sq over the area of 49 cm2.

8.
Indoor Air ; 30(5): 925-941, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32201992

RESUMO

Physicochemical properties between colloidal engineered nanomaterials (ENMs) and aerosols released from consumer spray products were characterized. A dynamic light scattering (DLS), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometer (ICP-MS) were used to evaluate the suspended ENMs in the products. Direct-reading instruments, TEM, and ICP-MS were used to characterize the properties of aerosolized ENMs. The aerosolized organic compounds with ENMs were assumed to be vaporized for a short time after spraying. The median diameter of ENMs in product solutions measured by DLS was about 200-350 nm, while individual particle was confirmed from 3 to 50 nm by TEM. The size of aerosolized ENMs was ranged from 7 to 44 nm, and their aggregates were about 100-1000 nm in near distance. Some inorganic substances including raw nanomaterials were also found in the aerosol. The particles released from the propellant sprays were identified in far distance, while they were not found in far distance when pump sprays were used. The number concentration from the propellant sprays increased up to 6000 particles/cm3 /g at near distance and dispersed to far distance, while the most of droplets emitted from pump sprays were settled down near sprayer's location. We found other metals besides labeled ENMs are included in each product and the characteristics of the particles are different when they are sprayed.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Nanoestruturas/análise , Aerossóis , Poeira , Exposição por Inalação , Tamanho da Partícula
9.
Neurosurg Focus ; 48(4): E13, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32234993

RESUMO

OBJECTIVE: The goal of this study was to evaluate the predictive value and relative contribution of noninvasive presurgical functional imaging modalities based on the authors' institutional experience in pursuing seizure-free surgical outcomes in children with medically refractory epilepsy. METHODS: This was a retrospective, single-institution, observational cohort study of pediatric patients who underwent evaluation and surgical treatment for medically refractory partial epilepsy between December 2003 and June 2016. During this interval, 108 children with medically refractory partial epilepsy underwent evaluation for localization and resective epilepsy surgery. Different noninvasive functional imaging modalities, including ictal SPECT, FDG-PET, and magnetoencephalography-magnetic source imaging, were utilized to augment a standardized paradigm (electroencephalography/semiology, MRI, and neuropsychology findings) for localization. Outcomes were evaluated at a minimum of 2 years (mean 7.5 years) utilizing area under the receiver operating characteristic curve analysis. Localizing modalities and other clinical covariates were examined in relation to long-term surgical outcomes. RESULTS: There was variation in the contribution of each test, and no single presurgical workup modality could singularly and reliably predict a seizure-free outcome. However, concordance of presurgical modalities yielded a high predictive value. No difference in long-term outcomes between inconclusive (normal or diffusely abnormal) and abnormal focal MRI results were found. Long-term survival analyses revealed a statistically significant association between seizure freedom and patients with focal ictal EEG, early surgical intervention, and no history of generalized convulsions. CONCLUSIONS: Comprehensive preoperative evaluation utilizing multiple noninvasive functional imaging modalities is not redundant and can improve pediatric epilepsy surgical outcomes.


Assuntos
Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Procedimentos Neurocirúrgicos , Convulsões/diagnóstico por imagem , Convulsões/cirurgia , Adolescente , Adulto , Pré-Escolar , Estudos de Coortes , Eletroencefalografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos
10.
Toxicol Appl Pharmacol ; 378: 114609, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31173787

RESUMO

Benzalkonium chloride (BAC), a disinfectant, and triethylene glycol (TEG), an organic solvent/sanitizer, are frequently combined in commercially available household sprays. To assess the respiratory effect of this combination, Sprague-Dawley rats were exposed to an aerosol containing BAC (0.5%, w/v) and TEG (10%, w/v) for up to 2 weeks in a whole-body inhalation chamber. BAC (4.1-4.5 mg/m3, sprayed from 0.5% solution) promoted pulmonary cell damage and inflammation as depicted by the increase in total protein, lactate dehydrogenase, polymorphonuclear leukocytes, and macrophage inflammatory protein-2 in the bronchoalveolar lavage fluid, whereas TEG (85.3-94.5 mg/m3, sprayed from 10% solution) did not affect the lung. Rats exposed to the BAC/TEG mixture for 2 weeks showed severe respiratory symptoms (sneezing, wheezing, breath shortness, and chest tightness), but no lung damage or inflammation was observed. However, significant ulceration and degenerative necrosis were observed in the nasal cavities of rats repeatedly exposed to the BAC/TEG mixture. The mass median aerodynamic diameters of the aqueous, BAC, TEG and BAC/TEG aerosols were 1.24, 1.27, 3.11 and 3.24 µm, respectively, indicating that TEG-containing aerosols have larger particles than those of the aqueous and BAC alone aerosols. These results suggest that the toxic effects of BAC and BAC/TEG aerosols on the different respiratory organs may be associated with the difference in particle diameter, since particle size is important in determining the deposition site of inhaled materials.


Assuntos
Compostos de Benzalcônio/toxicidade , Exposição por Inalação/efeitos adversos , Polietilenoglicóis/toxicidade , Administração por Inalação , Aerossóis/toxicidade , Animais , Líquido da Lavagem Broncoalveolar , Quimiocina CXCL2/metabolismo , Pulmão/efeitos dos fármacos , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley
11.
Nanotechnology ; 30(22): 225501, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-30731431

RESUMO

Nanopore structures were originally proposed for detection of biomolecule translocation through nanometer-scale pores that perforate membranes by transient changes in ionic current. In this study, these changes are utilized to detect corrosion of different metals in aqueous chlorine media. The corrosion behaviors of Cu, Al, Ti, and Cr were analyzed by monitoring the changes in ion current resulting from ion concentration variations in solutions due to corrosion of the metals. We observed that the Cu layer passivated by CuO x was severely corroded when a drastic change of ion current was induced, from 10 to 30 nS to the level of 104 nS, as soon as the bias voltage was applied. In the case of Al passivated by thin AlO x , the conductance increased from 10-30 to 166 ± 52 nS and became saturated. Highly localized pitting corrosion was observed on the periphery of the nanopore, where the electrical field was most concentrated. Finally, we observed that Ti and Cr passivated by oxide showed long-term stability without corrosion in 1 M KCl in the pH range of 4-11.

12.
Nanotechnology ; 30(19): 195602, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30721897

RESUMO

Here, we explore the possibility of using peptide-based materials as a membrane in solid-state nanopore devices in an effort to develop a sequence-specific, programmable biological membrane platform. We use a recently developed tyrosine-mediated self-assembly peptide sheet. At the air/water interface, the 5mer peptide YFCFY self-assembles into a uniform and robust two-dimensional (2D) structure, and the peptide sheet is easily transferred to a low-noise glass substrate. The thickness of the peptide membrane can be adjusted to approximately 5 nm (or even to 2 nm) by an etching process, and the diameters of the peptide nanopores can be precisely controlled using a focused electron beam with an attuned spot size. The ionic current noise of the peptide nanopore is comparable to those of typical silicon nitride nanopores or multilayer 2D materials. Using this membrane, we successfully observe translocation of 1000 bp double-stranded DNA with a sufficient signal-to-noise ratio of ∼30 and an elongated translocation speed of ∼1 bp µs-1. Our results suggest that the self-assembled peptide film can be used as a sensitive nanopore membrane and employed as a platform for applying biological functionalities to solid-state substrates.


Assuntos
DNA de Cadeia Simples/química , Peptídeos/química , Membranas Artificiais , Nanoporos , Nanotecnologia/instrumentação
13.
Dev Med Child Neurol ; 61(6): 661-666, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30714130

RESUMO

AIM: This population-based study aimed to estimate the impact of neonatal seizures on subsequent neurological outcomes, regardless of underlying etiology. METHOD: We performed a retrospective cohort study (1st January 2009-31st December 2014), using a USA nationwide claims database. Newborn infants enrolled in 2009 were followed for up to 6 years. Neonatal seizures were identified by combining the International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code of 779.0 (convulsions in newborn), procedure codes of electroencephalogram and brain imaging, and antiepileptic drugs claims. Cox regression models were built to estimate the independent impact of neonatal seizures on developing epilepsy, intellectual disability, psychiatric/behavioral disorders, and headache. RESULTS: Out of 490 071 newborn infants (251 850 males [51.4%], 238 221 females [48.6%]), 800 neonatal seizure cases were identified. After controlling for sex, birthweight, preterm birth status, and underlying etiology, neonates with seizures were more likely to have epilepsy (hazard ratio=32.7; 95% confidence interval [CI]=27.7-38.7; p<0.001), intellectual disability (hazard ratio=2.0; 95% CI=1.8-2.3; p<0.001), and headache (hazard ratio=1.6; 95% CI=1.1-2.2; p=0.013) than those without seizures. INTERPRETATION: Observed covariates being equal, seizures in neonates appeared to play a significant role in developing epilepsy, intellectual disability, and headache. The findings showed a detrimental impact of the event in the very early life on neurological outcomes in later life. WHAT THIS PAPER ADDS: Seizures had their own impact on the development of adverse neurological outcomes. The magnitude of impact was quite large in epilepsy.


Assuntos
Epilepsia/epidemiologia , Cefaleia/epidemiologia , Doenças do Recém-Nascido/epidemiologia , Deficiência Intelectual/epidemiologia , Convulsões/epidemiologia , Pré-Escolar , Bases de Dados Factuais , Epilepsia/etiologia , Feminino , Cefaleia/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Convulsões/complicações , Estados Unidos/epidemiologia
14.
BMC Pregnancy Childbirth ; 19(1): 241, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296172

RESUMO

BACKGROUND: The prediction of preterm birth (PTB) is important in the management of symptomatic preterm labour women. We evaluated the effectiveness of the foetal fibronectin (fFN) test for predicting PTB in symptomatic preterm labour women with consideration of physiologic changes in cervical length (CL) during pregnancy. METHODS: This prospective study included 85 women with symptomatic preterm labour of a singleton pregnancy. Positive fFN was defined as a fFN level of > 50 ng/mL in cervicovaginal secretion, while a short CL was defined as that below 25th percentile at the corresponding gestational age. We evaluated effectiveness of the fFN test, CL, and the combination of these two tests, including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), positive likelihood ratio (LR+), negative likelihood ratio (LR-) to predict the PTB within 7 and 14 days of testing and PTB at < 34 and 37 weeks of gestation. We also present the odds ratios (ORs) of the test results, defining the women with both negative results as the reference group. RESULTS: Of the 85 women, 31 (36.5%) showed a positive fFN and 44 (51.8%) had a short CL. PTB occurred within 7 and 14 days of testing and before 34 and 37 weeks of gestation in 17.6, 20.0, 23.5 and 49.4% of the women, respectively. The fFN and CL results showed low predictive effectiveness for the studied outcomes with LR+ (fFN, 1.5-1.9; CL, 1.0-1.5) and LR- (fFN, 0.7; CL, 0.7-0.9). The combined use of fFN and CL could not improve these results (LR+, 1.4-2.3; LR-, 0.7-0.9). However, the risk of PTB before 37 weeks was increased in women with positive fFN but not CL shortening compared to the reference group (odds ratio [OR], 3.8; 95% confidence interval [CI], 1.1-1.3). The risk of PTB before 34 weeks was increased in both positive fFN and CL compared to the reference group (OR, 8.1; 95% CI, 1.9-34.5). CONCLUSION: Although, our approach could not improve the ability to predict PTB, it could identify women at risk for delivery before 34 or 37 weeks of gestation. Therefore, it could be used to manage women with symptomatic preterm labour.


Assuntos
Sangue Fetal/química , Fibronectinas/sangue , Trabalho de Parto Prematuro/sangue , Nascimento Prematuro/diagnóstico , Diagnóstico Pré-Natal/estatística & dados numéricos , Adulto , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Valor Preditivo dos Testes , Gravidez , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Sensibilidade e Especificidade
15.
Environ Toxicol ; 34(5): 561-572, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30786124

RESUMO

Benzalkonium chloride (BAC) is a widely used disinfectant/preservative, and respiratory exposure to this compound has been reported to be highly toxic. Spray-form household products have been known to contain BAC together with triethylene glycol (TEG) in their solutions. The purpose of this study was to estimate the toxicity of BAC and TEG mixtures to pulmonary organs using in vitro and in vivo experiments. Human alveolar epithelial (A549) cells incubated with BAC (1-10 µg/mL) for 24 hours showed significant cytotoxicity, while TEG (up to 1000 µg/mL) did not affect cell viability. However, TEG in combination with BAC aggravated cell damage and inhibited colony formation as compared to BAC alone. TEG also exacerbated BAC-promoted production of reactive oxygen species (ROS) and reduction of glutathione (GSH) level in A549 cells. However, pretreatment of the cells with N-acetylcysteine (NAC) alleviated the cytotoxicity, indicating oxidative stress could be a mechanism of the toxicity. Quantification of intracellular BAC by LC/MS/MS showed that cellular distribution/absorption of BAC was enhanced in A549 cells when it was exposed together with TEG. Intratracheal instillation of BAC (400 µg/kg) in rats was toxic to the pulmonary tissues while that of TEG (up to 1000 µg/kg) did not show any harmful effect. A combination of nontoxic doses of BAC (200 µg/kg) and TEG (1000 µg/kg) promoted significant lung injury in rats, as shown by increased protein content and lactate dehydrogenase (LDH) activity in bronchoalveolar lavage fluids (BALF). Moreover, BAC/TEG mixture recruited inflammatory cells, polymorphonuclear leukocytes (PMNs), in terminal bronchioles and elevated cytokine levels, tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in BALF. These results suggest that TEG can potentiate BAC-induced pulmonary toxicity and inflammation, and thus respiratory exposure to the air mist from spray-form products containing this chemical combination is potentially harmful to humans.


Assuntos
Compostos de Benzalcônio/toxicidade , Lesão Pulmonar/induzido quimicamente , Pulmão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/induzido quimicamente , Polietilenoglicóis/toxicidade , Células A549 , Animais , Compostos de Benzalcônio/administração & dosagem , Compostos de Benzalcônio/metabolismo , Líquido da Lavagem Broncoalveolar/química , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Citocinas/análise , Sinergismo Farmacológico , Humanos , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Masculino , Estresse Oxidativo/imunologia , Pneumonia/metabolismo , Pneumonia/patologia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/metabolismo , Ratos Sprague-Dawley
16.
Toxicol Ind Health ; 35(8): 507-519, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31462197

RESUMO

In commercial products such as household deodorants or biocides, didecyldimethylammonium chloride (DDAC) often serves as an antimicrobial agent, citral serves as a fragrance agent, and the excipient ethylene glycol (EG) is used to dissolve the active ingredients. The skin sensitization (SS) potentials of each of these substances are still being debated. Moreover, mixtures of DDAC or citral with EG have not been evaluated for SS potency. The in vitro alternative assay called human Cell Line Activation Test (h-CLAT) and Direct Peptide Reactivity Assay (DPRA) served to address these issues. On three independent runs of h-CLAT, DDAC and citral were predicted to be sensitizers while EG was predicted to be a non-sensitizer and also by the DPRA. Mixtures of DDAC or citral with EG at ratios of 7:3 and 1:4 w/v were all positive by the h-CLAT in terms of SS potential but SS potency was mitigated as the proportion of EG increased. Citral and its EG mixtures were all positive but DDAC and its EG mixtures were all negative by the DPRA, indicating that the DPRA method is not suitable for chemicals with pro-hapten characteristics. Since humans can be occupationally or environmentally exposed to mixtures of excipients with active ingredients, the present study may give insights into further investigations of the SS potentials of various chemical mixtures.


Assuntos
Monoterpenos Acíclicos/efeitos adversos , Etilenoglicol/efeitos adversos , Excipientes/efeitos adversos , Compostos de Amônio Quaternário/efeitos adversos , Testes de Irritação da Pele/métodos , Pele/efeitos dos fármacos , Monoterpenos Acíclicos/administração & dosagem , Alternativas aos Testes com Animais/métodos , Antígeno B7-2/metabolismo , Bioensaio/métodos , Linhagem Celular , Etilenoglicol/administração & dosagem , Excipientes/administração & dosagem , Humanos , Molécula 1 de Adesão Intercelular/metabolismo
17.
Clin Exp Allergy ; 48(11): 1464-1473, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30126026

RESUMO

BACKGROUND: Clinical features of aspirin-exacerbated respiratory disease (AERD) are characterized by overproduction of cysteinyl leukotrienes (LT) and eosinophil activation, in which epithelial cells contribute to eosinophilic airway inflammation. Folliculin (FLCN) helps maintain the integrity of epithelial barrier, but little is known about FLCN in AERD. OBJECTIVE: We investigated the role of FLCN in the pathogenic mechanisms of AERD. METHODS: We recruited 178 subjects with AERD, 276 subjects with aspirin-tolerant asthma (ATA) and 71 normal healthy controls (NC) at Ajou Medical Center. Levels of FLCN and interleukin (IL)-8 in sera and supernatants were measured by ELISA. Peripheral blood eosinophils isolated from asthmatic patients were cocultured with human airway epithelial cells (HAECs) pretreated with LTE4 , dexamethasone and montelukast. The intracellular expressions of FLCN, tight (TJ) (occludins, claudin-1) and adherens (AJ) junctions (E-cadherin) were analysed by Western blotting. shRNA was used to down-regulate FLCN (shFLCN) in HAECs. RESULTS: Serum FLCN levels were significantly higher in AERD group than in ATA and NC groups (all P < 0.001). The cut-off value of 56.6 pg/mL was used to define the high FLCN phenotype (highFLCN). Asthmatic patients with highFLCN were associated with increased airway hyperresponsiveness to methacholine (P = 0.015). The serum FLCN level could discriminate AERD group from NC group with 82% sensitivity (AUC = 0.793, P < 0.001). When HAECs were exposed to LTE4 , FLCN release was increased significantly (P < 0.05), which were amplified along with disruption of TJ and AJ expressions when HAECs were cocultured with eosinophils and LTE4 (all P < 0.05); these effects were suppressed by dexamethasone and montelukast. FLCN knockdown reduced IL-8 release and occludin expression from shFLCN HAECs. CONCLUSIONS: Our findings suggest that high LT and airway eosinophilia increased FLCN release from HAECs, which enhance epithelial activation and disruption. Modulation of FLCN may be a potential target for AERD.


Assuntos
Aspirina/efeitos adversos , Estrona/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Doenças Respiratórias/etiologia , Doenças Respiratórias/metabolismo , Adulto , Asma Induzida por Aspirina , Biomarcadores , Linhagem Celular , Biologia Computacional/métodos , Citocinas/metabolismo , Eosinófilos/imunologia , Eosinófilos/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Inflamação/diagnóstico , Inflamação/etiologia , Inflamação/metabolismo , Junções Intercelulares/metabolismo , Masculino , Pessoa de Meia-Idade , Fenótipo , República da Coreia , Testes de Função Respiratória , Mucosa Respiratória/patologia , Doenças Respiratórias/diagnóstico
18.
Epilepsy Behav ; 85: 37-44, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29906700

RESUMO

OBJECTIVE: The objective of this study was to determine patient characteristics and antiepileptic drug (AED) treatment patterns in patients with newly diagnosed epilepsy in a United States (US) population followed for ≥180 days. METHODS: In this retrospective cohort study, Commercial, Supplemental Medicare, and Medicaid insurance claims from US-based Truven Health MarketScan® claims database were analyzed for incident epilepsy cases (index date: January 2010-June 2013; prior baseline of 2 years [1 year for ages 1 to <2 years; none for those <1 year]). Cases met epilepsy criteria consistent with the International League Against Epilepsy diagnostic guidelines, with continuous medical and pharmacy enrollment without an epilepsy or seizure diagnosis or AED prescription during baseline. Treatment was classified as monotherapy (one AED for ≥90 continuous days), polytherapy (at least two AEDs for ≥90 days), or untreated (no AED claims but other pharmacy or healthcare claims). Treatment pattern comparisons used matched cohorts across seizure types. RESULTS: Of 58,757 incident cases, 50,838 had a follow-up of ≥180 days. The median (range) follow-up duration was 529 (180-1096) days. Patient characteristics were similar across seizure types (matched focal vs. generalized epilepsy, N = 9949 each). At 6 and 12 months post-index, 46.8% and 52.2% of patients, respectively, had received AED treatment. Of 29,226 patients receiving treatment, 74.7% and 1.6% received monotherapy and polytherapy for ≥90 days, respectively, as first-line treatment; remaining patients received AED for <90 days and were excluded. The probability of remaining on initial treatment after 1 year was 61.0% for monotherapy and 36.5% for polytherapy. The most common first-line AEDs were levetiracetam (44.4%), phenytoin (6.5%), valproic acid (6.4%), lamotrigine (6.3%), oxcarbazepine (5.7%), topiramate (5.5%), and gabapentin (5.3%). CONCLUSION: Although the majority of treated patients received AED monotherapy consistent with guidelines, suboptimal rates of AED treatment and persistence of first-line treatment after initial epilepsy diagnosis suggest that efforts are needed to improve patient care.


Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/epidemiologia , Convulsões/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Bases de Dados Factuais , Quimioterapia Combinada , Epilepsia/diagnóstico , Epilepsia/tratamento farmacológico , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Estudos Retrospectivos , Convulsões/diagnóstico , Convulsões/tratamento farmacológico , Estados Unidos/epidemiologia , Adulto Jovem
19.
Biochim Biophys Acta ; 1859(8): 1056-70, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27206966

RESUMO

MAP kinase phosphatase (MKP)-1 plays a pivotal role in controlling MAP kinase (MAPK)-dependent (patho) physiological processes. Although MKP-1 gene expression is tightly regulated at multiple levels, the underlying mechanistic details remain largely unknown. In this study, we demonstrate that MKP-1 expression is regulated at the post-transcriptional level by 22(R)-hydroxycholesterol [22(R)-HC] through a novel mechanism. 22(R)-HC induces Hu antigen R (HuR) phosphorylation, cytoplasmic translocation and binding to MKP-1 mRNA, resulting in stabilization of MKP-1 mRNA. The resulting increase in MKP-1 leads to suppression of JNK-mediated inflammatory responses in brain astrocytes. We further demonstrate that 22(R)-HC-induced phosphorylation of nuclear HuR is mediated by PKCα, which is activated in the cytosol by increases in intracellular Ca(2+) levels mediated by the phospholipase C/inositol 1,4,5-triphosphate receptor (PLC/IP3R) pathway and translocates from cytoplasm to nucleus. In addition, pharmacological interventions reveal that metabotropic glutamate receptor5 (mGluR5) is responsible for the increases in intracellular Ca(2+) that underlie these actions of 22(R)-HC. Collectively, our findings identify a novel anti-inflammatory mechanism of 22(R)-HC, which acts through PKCα-mediated cytoplasmic shuttling of HuR to post-transcriptionally regulate MKP-1 expression. These findings provide an experimental basis for the development of a RNA-targeted therapeutic agent to control MAPK-dependent inflammatory responses.


Assuntos
Astrócitos/metabolismo , Fosfatase 1 de Especificidade Dupla/genética , Proteína Semelhante a ELAV 1/genética , Hidroxicolesteróis/farmacologia , Proteína Quinase C-alfa/genética , RNA Mensageiro/genética , Receptor de Glutamato Metabotrópico 5/genética , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Cálcio/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Fosfatase 1 de Especificidade Dupla/metabolismo , Proteína Semelhante a ELAV 1/agonistas , Proteína Semelhante a ELAV 1/metabolismo , Regulação da Expressão Gênica , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Ligação Proteica , Proteína Quinase C-alfa/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , Ratos , Receptor de Glutamato Metabotrópico 5/metabolismo , Transdução de Sinais , Fosfolipases Tipo C/genética , Fosfolipases Tipo C/metabolismo
20.
Pediatr Allergy Immunol ; 28(6): 551-556, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28631848

RESUMO

BACKGROUND: There are controversial data about the effects of sun exposure on atopic dermatitis (AD). We evaluated the association between solar ultraviolet radiation (UVR) exposure and AD symptoms in children. METHODS: Eighty-two children under 6 years (48 boys and 34 girls) with AD living in Seoul, Korea, were enrolled and followed for 12 months between September 2013 and August 2014. Daily symptoms were recorded to describe the degree of itching, sleep disturbance, erythema, dryness, oozing, and edema. We assessed solar UVR by measuring radiation heat flux over the 290-400 nm wavelength range using thermopiles. A generalized linear mixed model and a generalized additive mixed model were used to evaluate the effects of UVR exposure on AD symptoms after adjusting for age, sex, outdoor temperature, outdoor humidity, and ambient air pollution. RESULTS: Symptom records of 12 915 person-days were analyzed. UVR showed a significantly positive relationship with AD symptoms. Over the study period, an increase in UVR by 10 W/cm2 was associated with a 1.46% increase in AD symptoms (95% CI: 0.85-2.07) on the exposure day. An increase in the 6-day average level of UVR of the previous 5 days and the current day by 10 W/cm2 was associated with a 3.58% (95% CI: 2.60-4.56) increase in AD symptoms. UVR exposure significantly increased AD symptoms in autumn, but decreased them in winter. CONCLUSIONS: Atopic dermatitis symptoms in children are likely to be affected by exposure to solar UVR with a cumulative effect, and this effect is different according to season.


Assuntos
Dermatite Atópica/prevenção & controle , Exposição Ambiental , Estações do Ano , Raios Ultravioleta , Pré-Escolar , Dermatite Atópica/diagnóstico , Dermatite Atópica/etiologia , Feminino , Humanos , Lactente , Modelos Lineares , Estudos Longitudinais , Masculino , Fatores de Proteção , República da Coreia
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