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1.
Clin Gastroenterol Hepatol ; 21(13): 3270-3284.e77, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37331411

RESUMO

BACKGROUND AND AIMS: Owing to 2018 expanded diagnostic criteria for eosinophilic esophagitis (EoE) and thus a possible increase in diagnosis, previous studies on the global incidence and prevalence of EoE may need to be updated. We aimed to describe global, regional, and national trends in the incidence and prevalence of EoE from 1976 to 2022 and analyze their associations with geographic, demographic, and social factors through a systematic review. METHODS: We searched the PubMed/MEDLINE, Embase, CINAHL, Google Scholar, and Cochrane databases from their inception dates to December 20, 2022, for studies that reported the incidence or prevalence of EoE in the general population. We calculated the global incidence and prevalence of EoE using pooled estimates with 95% confidence intervals (CIs) and performed subgroup analysis based on age, sex, race, geographical area, World Bank income group, and diagnostic criteria of EoE. RESULTS: Forty studies met the eligibility criteria, including over 288 million participants and 147,668 patients with EoE from 15 countries across the five continents. The global pooled incidence and prevalence of EoE were 5.31 cases per 100,000 inhabitant-years (95% CI, 3.98-6.63; number of studies, 27; sample population, 42,191,506) and 40.04 cases per 100,000 inhabitant-years (95% CI, 31.10-48.98; number of studies, 20; sample population, 30,467,177), respectively. The pooled incidence of EoE was higher in high-income countries (vs low- or middle-income countries), males, and North America (vs Europe and Asia). The global prevalence of EoE followed a similar pattern. The pooled prevalence of EoE gradually increased from 1976 to 2022 (1976-2001; 8.18; 95% CI, 3.67-12.69 vs 2017-2022; 74.42; 95% CI, 39.66-109.19 cases per 100,000 inhabitant-years). CONCLUSIONS: The incidence and prevalence of EoE have increased substantially and vary widely across the world. Further research is needed to evaluate the incidence and prevalence of EoE in Asia, South America, and Africa.


Assuntos
Esofagite Eosinofílica , Masculino , Humanos , Esofagite Eosinofílica/diagnóstico , Prevalência , Incidência , Europa (Continente) , América do Norte
2.
Bioinformatics ; 38(22): 5116-5118, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36130060

RESUMO

MOTIVATION: Multi-omic profiling data, such as The Cancer Genome Atlas and pharmacogenomic data, facilitate research into cancer mechanisms and drug development. However, it is not easy for researchers to connect, integrate and analyze huge and heterogeneous data, which is a major obstacle to the utilization of cancer genomic data. RESULTS: We developed Cancer Genome Viewer (CGV), a user-friendly web service that provides functions to integrate and visualize cancer genome data and pharmacogenomic data. Users can easily select and customize the samples to be analyzed with the pre-defined selection options for patients' clinic-pathological features from multiple datasets. Using the customized dataset, users can perform subsequent data analyses comprehensively, including gene set analysis, clustering or survival analysis. CGV also provides pre-calculated drug response scores from pharmacogenomic data, which may facilitate the discovery of new cancer targets and therapeutics. AVAILABILITY AND IMPLEMENTATION: CGV web service is implemented with the R Shiny application at http://cgv.sysmed.kr and the source code is freely available at https://git.sysmed.kr/sysmed_public/cgv. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Neoplasias , Farmacogenética , Humanos , Análise de Dados , Software , Genoma , Neoplasias/tratamento farmacológico , Neoplasias/genética
3.
J Med Virol ; 95(2): e28456, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36602052

RESUMO

With the ongoing COVID-19 pandemic, several previous studies from different countries showed that physical activity (PA) decreased during the COVID-19 outbreak. However, few studies have examined the recent tendency of PA in the adolescent population. Thus, we aimed to investigate the long-term trend of PA in Korean youth and the prevalence changes between before and during the COVID-19 pandemic. Data from Korea Youth Risk Behavior Web-Based Survey (KYRBS) was collected for consecutive years between 2009 and 2021. The period was separated into prepandemic (2009-2019), early-pandemic (2020), and mid-pandemic (2021). Self-reported amount of PA was categorized into four groups (insufficient, aerobic, muscle strengthening, and both physical activities) according to World Health Organization (WHO) PA guidelines. A total of 840 488 adolescents aged 12-18 who fully responded to the survey were selected (response rate: 95.2%). The 13-year trends in the proportion of adolescents who reported aerobic and muscle-strengthening activities met or exceeded 2020 WHO exercise guidelines for adolescents plateaued (11.9% from 2009 to 2011, 14.2% from 2018 to 2019, 14.4% from 2020, and 14.0% from 2021); however, the slope decreased during the pandemic (ßdiff , -0.076; 95% confidence interval [CI], -0.123 to -0.029). Proportion of sufficient aerobic exercise among adolescents sharply decreased midst the pandemic (28.0% from 2009 to 2011, 29.4% from 2018 to 2019, and 23.8% from 2020; ßdiff , -0.266; 95% CI, -0.306 to -0.226) but increased again in 2021 (26.0% from mid-COVID 19; 95% CI, 25.4-26.7). Similar patterns were observed in Metabolic Equivalent Task (MET) score (MET-min/week; 804.1 from 2018 to 2019, 720.9 from 2020, and 779.6 from 2021). The mean difference in MET score between pre-COVID and post-COVID was -55.4 MET-min/week (95% CI, -70.5 to -40.3). Through a nationwide representative study, there was no significant difference with regard to the number of Korean adolescents who achieved the PA guidelines (pre and postpandemic); however, the prevalence of recommended levels of PA needs to increase more based on the trend before the COVID-19 outbreak. The findings of this study suggest reinforcement of the importance of public health policies for Korean youths to be more physically active, especially during and after the pandemic.


Assuntos
COVID-19 , Pandemias , Humanos , Adolescente , Estudos Transversais , COVID-19/epidemiologia , Exercício Físico/fisiologia , República da Coreia/epidemiologia
4.
Clin Exp Allergy ; 50(5): 585-596, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32053269

RESUMO

BACKGROUND: Immunologic function in innate and adaptive immunity changes with the ageing process. Thus, age-related cytokine profiles in chronic rhinosinusitis (CRS) need to be investigated for precision medicine. OBJECTIVE: The objective of this study was to characterize age-related changes in immunologic profiles according to CRS subtypes. METHODS: Subjects in control (n = 29), CRS without nasal polyps (CRSsNP, n = 86), and CRS with nasal polyps (eosinophilic NP: ENP, n = 81; non-eosinophilic NP: NENP, n = 113) were enrolled in this study. Twenty markers for type 1/2/3 inflammation and other inflammatory processes were measured in homogenates of sinonasal tissues and statistically analysed. RESULTS: In control tissues, type 2/3 and proinflammatory mediators showed an inverse correlation with age. CRSsNP and NENP showed an age-related increase in type 2 cytokines and a decline in type 3 cytokines. Interestingly, the age-related decrease in type 3 mediators was associated with those of CT scores in NENP. ENP showed an age-related increase in type 3 cytokines with type 2 mediators sustained at high levels. Smokers with ENP demonstrated age-associated increases in type 1/2/3 mediators as well as CT scores. These age-related patterns in each CRS were confirmed by statistically adjusting atopy status, smoking history, and disease duration. CONCLUSION: Age-associated cytokine changes differed among CRS subtypes and control tissues. CRSsNP and NENP demonstrated a decline in type 3 mediators and increase in type 2 mediators, whereas type 3 mediators increased with age in ENP.


Assuntos
Envelhecimento , Citocinas/metabolismo , Pólipos Nasais , Rinite , Sinusite , Adolescente , Adulto , Idoso , Envelhecimento/metabolismo , Envelhecimento/patologia , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/metabolismo , Pólipos Nasais/patologia , Rinite/metabolismo , Rinite/patologia , Sinusite/metabolismo , Sinusite/patologia
5.
Int J Mol Sci ; 20(3)2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30736433

RESUMO

Severe asthma is an extremely heterogeneous clinical syndrome in which diverse cellular and molecular pathobiologic mechanisms exist, namely endotypes. The current system for endotyping severe asthma is largely based on inflammatory cellular profiles and related pathways, namely the dichotomy of type 2 response (resulting in eosinophilic inflammation) and non-type 2 response (reinforcing non-eosinophilic inflammation involving neutrophils or less inflammatory cells), forming the basis of a development strategy for novel therapies. Although specific subgroups of type 2 severe asthma patients may derive benefit from modern precision medicine targeting type 2 cytokines, there is no approved and effective therapeutic agent for non-type 2 severe asthma, which comprises nearly 50% of all asthma patients. Importantly, the critical implication of endoplasmic reticulum (ER) stress and unfolded protein response-in close relation with several pivotal cellular immune/inflammatory platforms including mitochondria, NLRP3 inflammasome, and phosphoinositide 3-kinase-δ-in the generation of corticosteroid resistance is now being increasingly demonstrated in numerous experimental settings of severe asthma. Consistent with these findings, recent clinical data from a large European severe asthma cohort, in which molecular phenotyping as well as diverse clinical and physiological parameters from severe asthmatic patients were incorporated, suggest a brand new framework for endotyping severe asthma in relation to ER-associated mitochondria and inflammasome pathways. These findings highlight the view that ER stress-associated molecular pathways may serve as a unique endotype of severe asthma, and thus present a novel insight into the current knowledge and future development of treatment to overcome corticosteroid resistance in heterogeneous severe asthma.


Assuntos
Asma/etiologia , Asma/metabolismo , Estresse do Retículo Endoplasmático , Imunidade , Alérgenos/imunologia , Animais , Asma/diagnóstico , Biomarcadores , Citocinas/metabolismo , Eosinófilos/imunologia , Eosinófilos/metabolismo , Eosinófilos/patologia , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Organelas/metabolismo , Índice de Gravidade de Doença , Avaliação de Sintomas
6.
Thorax ; 73(8): 758-768, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29622694

RESUMO

BACKGROUND: Respiratory fungal exposure is known to be associated with severe allergic lung inflammation. Airway epithelium is an essential controller of allergic inflammation. An innate immune recognition receptor, nucleotide-binding domain, leucine-rich-containing family, pyrin-domain-containing-3 (NLRP3) inflammasome, and phosphoinositide 3 kinase (PI3K)-δ in airway epithelium are involved in various inflammatory processes. OBJECTIVES: We investigated the role of NLRP3 inflammasome in fungi-induced allergic lung inflammation and examined the regulatory mechanism of NLRP3 inflammasome, focusing on PI3K-δ in airway epithelium. METHODS: We used two in vivo models induced by exposure to Aspergillus fumigatus (Af) and Alternaria alternata (Aa), as well as an Af-exposed in vitro system. We also checked NLRP3 expression in lung tissues from patients with allergic bronchopulmonary aspergillosis (ABPA). RESULTS: Assembly/activation of NLRP3 inflammasome was increased in the lung of Af-exposed mice. Elevation of NLRP3 inflammasome assembly/activation was observed in Af-stimulated murine and human epithelial cells. Similarly, pulmonary expression of NLRP3 in patients with ABPA was increased. Importantly, neutralisation of NLRP3 inflammasome derived IL-1ß alleviated pathophysiological features of Af-induced allergic inflammation. Furthermore, PI3K-δ blockade improved Af-induced allergic inflammation through modulation of NLRP3 inflammasome, especially in epithelial cells. This modulatory role of PI3K-δ was mediated through the regulation of mitochondrial reactive oxygen species (mtROS) generation. NLRP3 inflammasome was also implicated in Aa-induced eosinophilic allergic inflammation, which was improved by PI3K-δ blockade. CONCLUSION: These findings demonstrate that fungi-induced assembly/activation of NLRP3 inflammasome in airway epithelium may be modulated by PI3K-δ, which is mediated partly through the regulation of mtROS generation. Inhibition of PI3K-δ may have potential for treating fungi-induced severe allergic lung inflammation.


Assuntos
Alternariose/enzimologia , Alternariose/imunologia , Aspergilose Broncopulmonar Alérgica/enzimologia , Aspergilose Broncopulmonar Alérgica/imunologia , Estresse do Retículo Endoplasmático/imunologia , Imunidade Inata/imunologia , Fosfatidilinositol 3-Quinases/imunologia , Animais , Aspergillus fumigatus , Biomarcadores/análise , Brônquios/citologia , Células Cultivadas , Células Epiteliais/imunologia , Feminino , Humanos , Inflamassomos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/imunologia
10.
Curr Allergy Asthma Rep ; 17(12): 82, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29119328

RESUMO

PURPOSE OF REVIEW: In this review, we will integrate recent knowledge on endoplasmic reticulum (ER) stress and allergy, thereby highlighting the therapeutic potential of ER stress in the context of precision medicine for allergic diseases. RECENT FINDINGS: Emerging evidence suggests that allergic diseases are very heterogeneous having numerous endotypes. This leads to the new era of modern medicine, which assumes that a particular endotype-driven therapy, called precision medicine, would be more efficacious in a specific group of patients rather than in all patients. Currently, a dichotomy involving type 2/non-type 2 immune response underlies most of the studies on inflammatory and immunologic mechanisms of allergic disorders. Whereas there are several approved or investigational endotype-driven therapeutic agents targeting type 2 immune responses, investigation of mechanisms and endotype-driven interventions regarding non-type 2 immune response lags far behind. Considering that non-type 2 immune response may represent a significant proportion of allergic disease, particularly corticosteroid-resistant severe disease, defining a novel concept of endotype-driven approach may be essential. Recently, stress responses originate from the endoplasmic reticulum (ER) and the associated inflammatory molecular platform has been suggested as a crucial player of immune and inflammatory responses. This implies that ER stress-related pathways may represent a new endotype-driven therapeutic strategy in the treatment of allergic diseases.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Hipersensibilidade/fisiopatologia , Animais , Humanos , Hipersensibilidade/terapia , Medicina de Precisão
11.
Nature ; 479(7373): 338-44, 2011 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-22094694

RESUMO

As silicon-based electronics approach the limit of improvements to performance and capacity through dimensional scaling, attention in the semiconductor field has turned to graphene, a single layer of carbon atoms arranged in a honeycomb lattice. Its high mobility of charge carriers (electrons and holes) could lead to its use in the next generation of high-performance devices. Graphene is unlikely to replace silicon completely, however, because of the poor on/off current ratio resulting from its zero bandgap. But it could be used to improve silicon-based devices, in particular in high-speed electronics and optical modulators.

12.
Thorax ; 71(1): 52-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26543090

RESUMO

BACKGROUND: Sensitisation with Aspergillus fumigatus (Af) is known to be associated with severe allergic lung inflammation, but the mechanism remains to be clarified. Phosphoinositide 3-kinase (PI3K)-δ and endoplasmic reticulum (ER) stress are suggested to be involved in steroid-resistant lung inflammation. We aimed to elucidate the role of PI3K-δ and its relationship with ER stress in fungus-induced allergic lung inflammation. METHODS: Using Af-exposed in vivo and in vitro experimental systems, we examined whether PI3K-δ regulates ER stress, thereby contributing to steroid resistance in fungus-induced allergic lung inflammation. Moreover, we checked expression of an ER stress marker in lung tissues isolated from patients with allergic bronchopulmonary aspergillosis. RESULTS: Af-exposed mice showed that ER stress markers, unfolded protein response (UPR)-related proteins, phosphorylated Akt, generation of mitochondrial reactive oxygen species (mtROS), eosinophilic allergic inflammation, and airway hyperresponsiveness (AHR) were increased in the lung. Similarly, glucose-regulated protein 78 was increased in lung tissues of patients with ABPA. A PI3K-δ inhibitor reduced Af-induced increases in ER stress markers, UPR-related proteins, allergic inflammation and AHR in mice. However, dexamethasone failed to reduce Af-induced allergic inflammation, AHR and elevation of ER stress. Administration of an ER stress inhibitor or a mtROS scavenger improved Af-induced allergic inflammation. The PI3K-δ inhibitor reduced Af-induced mtROS generation and the mtROS scavenger ameliorated ER stress. In primary cultured tracheal epithelial cells, Af-induced ER stress was inhibited by blockade of PI3K-δ. CONCLUSIONS: These findings suggest that PI3K-δ regulates Af-induced steroid-resistant eosinophilic allergic lung inflammation through ER stress.


Assuntos
Aspergilose Broncopulmonar Alérgica/enzimologia , Aspergilose Broncopulmonar Alérgica/etiologia , Estresse do Retículo Endoplasmático/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Biomarcadores/análise , Western Blotting , Lavagem Broncoalveolar , Proteínas Estimuladoras de Ligação a CCAAT/análise , Feminino , Glutationa/análise , Dissulfeto de Glutationa/análise , Imunoglobulina E/sangue , Inflamação/enzimologia , Inflamação/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Quinazolinas/farmacologia , RNA Interferente Pequeno/análise
13.
Cell Immunol ; 297(1): 40-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26123077

RESUMO

Incomplete clearance of apoptotic cells and reactive oxygen species (ROS) release are known to trigger inflammasome activation causing severe inflammation in acute lung injury and various metabolic and autoimmune diseases. Moreover, it has been reported that apoptotic cell clearance and ROS-mediated apoptosis critically depend on mitochondrial uncoupling protein-2 (UCP2). However, the relationship between UCP2 and inflammasome activation has not been studied. This report investigates the role of UCP2 in the expression and activation of NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome in human macrophages. We found that UCP2 overexpression significantly enhanced the expression levels of NLRP3. The NLRP3 expression levels were significantly suppressed in THP1 cells treated with genipin, a UCP2 inhibitor, compared to controls. In addition, genipin altered adenosine triphosphate (ATP)- and hydrogen peroxide (H2O2)-mediated interleukin-1 beta (IL-1ß) secretion and significantly suppressed caspase-1 activity in inflammasome-activated human macrophages. Taken together, our results suggest that genipin modulates NLRP3 inflammasome activation and ATP- or H2O2-mediated IL-1ß release.


Assuntos
Proteínas de Transporte/antagonistas & inibidores , Inflamassomos/efeitos dos fármacos , Canais Iônicos/imunologia , Iridoides/farmacologia , Proteínas Mitocondriais/imunologia , Apoptose/imunologia , Proteínas de Transporte/biossíntese , Proteínas de Transporte/metabolismo , Caspase 1/imunologia , Células Cultivadas , Ativação Enzimática/imunologia , Regulação da Expressão Gênica , Humanos , Inflamassomos/metabolismo , Inflamação/imunologia , Interleucina-1beta/imunologia , Canais Iônicos/antagonistas & inibidores , Canais Iônicos/biossíntese , Macrófagos/imunologia , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/biossíntese , Proteína 3 que Contém Domínio de Pirina da Família NLR , Espécies Reativas de Oxigênio/imunologia , Proteína Desacopladora 2
14.
J Nanosci Nanotechnol ; 15(11): 8706-10, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26726580

RESUMO

We report on new fabrication methods for a transparent, hierarchical, and patterned electrode comprised of either carbon nanotubes or zinc oxide nanorods. Vertically aligned carbon nanotubes or zinc oxide nanorod arrays were fabricated by either chemical vapor deposition or hydrothermal growth, in combination with photolithography. A transparent conductive graphene layer or zinc oxide seed layer was employed as the transparent electrode. On the patterned surface defined using photoresist, the vertically grown carbon nanotubes or zinc oxides could produce a concentrated electric field under applied DC voltage. This periodic electric field was used to align liquid crystal molecules in localized areas within the optical cell, effectively modulating the refractive index. Depending on the material and morphology of these patterned electrodes, the diffraction efficiency presented different behavior. From this study, we established the relationship between the hierarchical structure of the different electrodes and their efficiency for modulating the refractive index. We believe that this study will pave a new path for future optoelectronic applications.


Assuntos
Microeletrodos , Nanotecnologia/instrumentação , Nanotubos de Carbono/química , Nanotubos/química , Refratometria/instrumentação , Óxido de Zinco/química , Cristalização/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Teste de Materiais , Conformação Molecular , Nanotubos/efeitos da radiação , Nanotubos/ultraestrutura , Nanotubos de Carbono/efeitos da radiação , Nanotubos de Carbono/ultraestrutura , Espalhamento de Radiação , Óxido de Zinco/efeitos da radiação
15.
Am J Respir Cell Mol Biol ; 50(4): 667-77, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24219511

RESUMO

Insulin-like growth factor (IGF)-I has been recognized to play critical roles in the pathogenesis of asthma, whereas IGF-binding protein (IGFBP)-3 blocks crucial physiologic manifestations of asthma. IGF-I enhances subepithelial fibrosis, airway inflammation, airway hyperresponsiveness, and airway smooth muscle hyperplasia by interacting with various inflammatory mediators and complex signaling pathways, such as intercellular adhesion molecule-1, and the hypoxia-inducible factor/vascular endothelial growth factor axis. On the other hand, IGFBP-3 decreases airway inflammation and airway hyperresponsiveness through IGFBP-3 receptor-mediated activation of caspases, which subsequently inhibits NF-κB signaling pathway. It also inhibits the IGF-I/hypoxia-inducible factor/vascular endothelial growth factor axis via IGF-I-dependent and/or IGF-I-independent mechanisms. This Translational Review summarizes the role of IGF-I and IGFBP-3 in the context of allergic airway disease, and discusses the therapeutic potential of various strategies targeting the IGF-I and IGFBP-3 signaling pathways for the management of asthma.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/uso terapêutico , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Pulmão/efeitos dos fármacos , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos , Animais , Asma/metabolismo , Asma/fisiopatologia , Desenho de Fármacos , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Receptor IGF Tipo 1/metabolismo , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/uso terapêutico
16.
ScientificWorldJournal ; 2014: 431978, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24772022

RESUMO

We construct some results on the regularity of solutions and the approximate controllability for neutral functional differential equations with unbounded principal operators in Hilbert spaces. In order to establish the controllability of the neutral equations, we first consider the existence and regularity of solutions of the neutral control system by using fractional power of operators and the local Lipschitz continuity of nonlinear term. Our purpose is to obtain the existence of solutions and the approximate controllability for neutral functional differential control systems without using many of the strong restrictions considered in the previous literature. Finally we give a simple example to which our main result can be applied.


Assuntos
Modelos Teóricos , Algoritmos
17.
ACS Appl Mater Interfaces ; 15(23): 27853-27864, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37272377

RESUMO

Defect passivation using two-dimensional (2D)-layered perovskites with organic spacers on 3D bulk perovskites has been proposed as an effective strategy to improve perovskite solar cell stability and efficiency. Specifically, fluorination of the organic spacers has been employed due to the resulting hydrophobic nature and the defect passivation characteristics. In addition to the type of functional groups attached to the spacer molecules, conformational changes of fluorine isomers on layered perovskites can provide an extended strategy to control a variety of opto-electrical properties related to the interlayer spacing. As a model system for the structural isomer of fluorinated spacers, meta-CF3 and para-CF3 groups anchored to phenethylammonium iodide (PEAI) spacer molecules are employed to synthesize 2D perovskites and to investigate their full potential as an interfacial modifier for perovskite solar cells. The fluorination position change leads to altered opto-electrical characteristics in layered perovskites. Although they possess identical functional groups, the different orientations of the functional groups used in the perovskite layer deposited on the 3D perovskite absorber result in distinct electrical properties of 2D/3D heterostructures due to dissimilar intermolecular interactions. The 2D perovskite with meta-CF3-PEAI spacers exhibits an enhancement of the charge transport in the out-of-plane orientation and an improved suppression of the trap states of 3D perovskites while also providing a more favorable energy alignment for efficient charge transfers. Theoretical simulations are consistent with the experimental results. The structural isomers of fluorination anchoring to spacer cations alter the structural configuration of the spacer as well as the interlayer spacing that can improve the performance and the stability of 2D/3D perovskite solar cells.

18.
Database (Oxford) ; 20232023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37566630

RESUMO

Cell-cell interaction (CCI) is a crucial event in the development and function of multicellular organisms. The development of CCI databases is beneficial for researchers who want to analyze single-cell sequencing data or study CCI through molecular experiments. CCIs are known to act differently according to cellular and biological contexts such as cell types, gene mutations or disease status; however, previous CCI databases do not completely provide this contextual information pertaining to CCIs. We constructed a cell-cell interaction database (CCIDB) containing the biological and clinical contexts involved in each interaction. To build a database of cellular and tissue contexts, we collected 38 types of context features, which were categorized into seven categories, including 'interaction', 'cell type', 'cofactor', 'effector', 'phenotype', 'pathology' and 'reference'. CCIs were manually retrieved from 272 studies published recently (less than 6 years ago). In the current version of CCIDB, 520 CCIs and their 38 context features have been manually collected and curated by biodata engineers. We suggest that CCIDB is a manually curated CCI resource that is highly useful, especially for analyzing context-dependent alterations in CCIs. Database URL https://ccidb.sysmed.kr/.


Assuntos
Comunicação Celular , Bases de Dados Factuais
19.
Adv Mater ; 35(39): e2304533, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37390092

RESUMO

The small nanoparticle size and long-chain ligands in colloidal metal halide perovskite quantum dots (PeQDs) cause charge confinement, which impedes exciton dissociation and carrier extraction in PeQD solar cells, so they have low short-circuit current density Jsc , which impedes further increases in their power conversion efficiency (PCE). Here, a re-assembling process (RP) is developed for perovskite nanocrystalline (PeNC) films made of colloidal perovskite nanocrystals to increase Jsc in PeNC solar cells. The RP of PeNC films increases their crystallite size and eliminates long-chain ligands, and thereby overcomes the charge confinement in PeNC films. These changes facilitate exciton dissociation and increase carrier extraction in PeNC solar cells. By use of this method, the gradient-bandgap PeNC solar cells achieve a Jsc = 19.30 mA cm-2 without compromising the photovoltage, and yield a high PCE of 16.46% with negligible hysteresis and good stability. This work provides a new strategy to process PeNC films and pave the way for high performance PeNC optoelectronic devices.

20.
Nat Commun ; 14(1): 5819, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730734

RESUMO

Benefits of breastfeeding for both the mother and the child are well established, but a comprehensive and robust study to investigate the protective effect of breastfeeding and attenuated time effect stratified by cause of morbidity are lacking. This study is based on the nationwide birth cohort in Korea that includes data on all infants born from 2009 to 2015. Of 1,608,540 children, the median follow-up period was 8.41 years (interquartile range, 6.76-10.06). When compared to children with fully formula feeding, the hospital admission rate was 12% lower in those with partially breastfeeding and 15% lower in those with exclusive breastfeeding. The apparent protective effect of breastfeeding was reduced with increasing age. Our study provides potential evidence of the beneficial association of breastfeeding on subsequent hospital admissions. The protective effect declined over time as the children grew older. Encouraging any breastfeeding for at least the first 6 months among infants is an important public health strategy to improve overall child health.


Assuntos
Coorte de Nascimento , Aleitamento Materno , Criança , Lactente , Feminino , Humanos , República da Coreia/epidemiologia , Saúde da Criança , Hospitais
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