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1.
Ecotoxicol Environ Saf ; 262: 115119, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37327520

RESUMO

Eicosanoids play important roles in inflammation, allergy, fever, and immune responses. In the eicosanoid pathway, cyclooxygenase (COX) catalyzes the conversion of arachidonic acid to prostaglandins and is a crucial target of nonsteroidal anti-inflammatory drugs (NSAIDs). Thus, toxicological studies on the eicosanoid pathway are important for drug discovery and the evaluation of adverse health outcomes due to environmental contaminants. However, experimental models are limited owing to concerns regarding ethical standards. Thus, new alternative models for evaluating toxic effects on the eicosanoid pathway must be developed. To this end, we adopted an invertebrate species, Daphnia magna, as an alternative model. D. magna was exposed to ibuprofen, a major NSAID, for 6 and 24 h. Transcription of eicosanoid-related genes (pla2, cox, pgd synthase, pgd2r2, ltb4dh, and lox) was analyzed by qPCR, eicosanoids (arachidonic acid, prostaglandin F2, dihydroxy prostaglandin F2, and 5-hydroxyeicosatetraenoate) were quantified by multiple reaction monitoring, and enzyme-linked immunosorbent assay was used to determine protein levels of arachidonic acid and prostaglandin E2 (PGE2). After 6 h of exposure, transcription of the pla2 and cox genes was downregulated. In addition, the whole-body level of arachidonic acid, an upstream of COX pathway, increased by over 1.5-fold. The levels of PGE2, a downstream of COX pathway, decreased after 24 h of exposure. According to our results, it is expected that the eicosanoid pathway might be conserved in D. magna, at least partially. This indicates the plausibility of D. magna as an alternative model for the screening of new drugs or chemical toxicity.

2.
Mikrochim Acta ; 189(1): 35, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34940914

RESUMO

MicroRNAs (miRNAs), found in blood and body fluids, have emerged as potential non-invasive biomarkers for disease and injury. miRNAs are quantitatively evaluated using typical RNA analysis methods such as the quantitative reverse transcription polymerase chain reaction, microarrays, and Northern blot, all of which require complex procedures and expensive reagents. To utilize miRNAs as practical biomarkers, it will be helpful to develop simple and user-friendly sensors. In this study, a paper-based miRNA sensor was developed by combining two methods: (1) target-recycled DNAzyme (Dz) amplification and (2) graphene oxide-assisted Dz blotting on paper. The Dz spots on paper caused a miRNA-dependent color change in presence of colorimetric reagents and facilitated the quantification of absolute amount of the target miRNA, irrespective of the volume, with high reproducibility. This approach is technologically straightforward and enables quantification of as low as 7.75 fmol miRNA using a portable smartphone.


Assuntos
Colorimetria/métodos , Grafite/química , MicroRNAs/análise , Papel , Benzotiazóis/química , Colorimetria/instrumentação , DNA Catalítico/química , Hemina/química , Peróxido de Hidrogênio/química , Indicadores e Reagentes/química , Limite de Detecção , MicroRNAs/química , Reprodutibilidade dos Testes , Smartphone , Ácidos Sulfônicos/química
3.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805345

RESUMO

Acrylamide is a commonly used industrial chemical that is known to be neurotoxic to mammals. However, its developmental toxicity is rarely assessed in mammalian models because of the cost and complexity involved. We used zebrafish to assess the neurotoxicity, developmental and behavioral toxicity of acrylamide. At 6 h post fertilization, zebrafish embryos were exposed to four concentrations of acrylamide (10, 30, 100, or 300 mg/L) in a medium for 114 h. Acrylamide caused developmental toxicity characterized by yolk retention, scoliosis, swim bladder deficiency, and curvature of the body. Acrylamide also impaired locomotor activity, which was measured as swimming speed and distance traveled. In addition, treatment with 100 mg/L acrylamide shortened the width of the brain and spinal cord, indicating neuronal toxicity. In summary, acrylamide induces developmental toxicity and neurotoxicity in zebrafish. This can be used to study acrylamide neurotoxicity in a rapid and cost-efficient manner.


Assuntos
Acrilamida/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Síndromes Neurotóxicas/fisiopatologia , Peixe-Zebra/crescimento & desenvolvimento , Acrilamida/farmacologia , Sacos Aéreos/patologia , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Embrião não Mamífero/fisiopatologia , Desenvolvimento Embrionário/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Escoliose/etiologia , Natação , Peixe-Zebra/fisiologia
4.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199418

RESUMO

Since neurodevelopmental disorders (NDDs) influence more than 3% of children worldwide, there has been intense investigation to understand the etiology of disorders and develop treatments. Although there are drugs such as aripiprazole, risperidone, and lurasidone, these medications are not cures for the disorders and can only help people feel better or alleviate their symptoms. Thus, it is required to discover therapeutic targets in order to find the ultimate treatments of neurodevelopmental disorders. It is suggested that abnormal neuronal morphology in the neurodevelopment process is a main cause of NDDs, in which the serotonergic system is emerging as playing a crucial role. From this point of view, we noticed the correlation between serotonin receptor subtype 7 (5-HT7R) and NDDs including autism spectrum disorder (ASD), fragile X syndrome (FXS), and Rett syndrome (RTT). 5-HT7R modulators improved altered behaviors in animal models and also affected neuronal morphology via the 5-HT7R/G12 signaling pathway. Through the investigation of recent studies, it is suggested that 5-HT7R could be a potential therapeutic target for the treatment of NDDs.


Assuntos
Terapia de Alvo Molecular/métodos , Transtornos do Neurodesenvolvimento/metabolismo , Receptores de Serotonina/metabolismo , Animais , Humanos , Transtornos do Neurodesenvolvimento/tratamento farmacológico , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico , Agonistas do Receptor de Serotonina/farmacologia , Agonistas do Receptor de Serotonina/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
5.
Br J Clin Pharmacol ; 86(2): 372-379, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31658396

RESUMO

AIMS: We performed a first-in-human study with HL2351, a novel hybrid Fc-fused interleukin (IL)-1 receptor antagonist, to evaluate its tolerability, pharmacokinetics and pharmacodynamics (PD) after a single subcutaneous (SC) administration in healthy subjects. METHODS: A randomized, double-blind, placebo- and active-controlled, dose-escalation study was conducted. Eligible subjects randomly received a single SC administration of HL2351 (1, 2, 4, 8 and 12 mg/kg) or placebo in a ratio of 8:2. Subjects in the active-controlled group received a single SC administration of anakinra at 100 mg. Serial blood samples were collected for pharmacokinetics and PD analyses. An ex-vivo activation test was performed to evaluate the PD using peripheral blood mononuclear cells treated with IL-1ß. Anti-HL2351 antibodies were determined at baseline and 29 days postdose. Tolerability was assessed throughout the study. RESULTS: HL2351 was eliminated more slowly than anakinra (terminal half-life: 27.21-45.28 vs 3.97 h). Serum concentrations of HL2351 were increased dose-proportionally. The mean apparent clearance of HL2351 were 0.6, 0.66, 0.75, 0.51, 0.65 L/h at 1, 2, 4, 8 and 12 mg/kg, respectively. The percent inhibition of IL-6 expression varied widely (range: 0-92.1%), showing no clear trend or discernible difference between HL2351, anakinra and placebo. HL2351 was well tolerated after a single SC administration. CONCLUSION: HL2351 was well tolerated and showed linear pharmacokinetic characteristics after a single SC administration at doses up to 12 mg/kg in healthy subjects. HL2351 remained in the body 7-11 times longer than anakinra. HL2351 can be developed as a potential therapeutic alternative to anakinra.


Assuntos
Proteína Antagonista do Receptor de Interleucina 1 , Leucócitos Mononucleares , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Meia-Vida , Voluntários Saudáveis , Humanos , Proteína Antagonista do Receptor de Interleucina 1/efeitos adversos , Receptores de Interleucina-1
6.
Anal Bioanal Chem ; 412(1): 233-242, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31828375

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs, which are involved in RNA silencing and post-transcriptional regulation of gene expression. Numerous studies have determined the expression of certain miRNAs in specific tissues and cell types, and their aberrant expression is associated with a variety of serious diseases such as cancers, immune-related diseases, and many infectious diseases. This suggests that miRNAs may be attractive and promising non-invasive biomarkers of diseases. In this study, we established a graphene oxide (GO)-based fluorescence/colorimetric dual sensing platform for miRNA by using a newly designed probe. The probe was designed to form a hairpin-like configuration with a fluorescent dye-labeled long tail, possessing a guanine (G)-rich DNAzyme domain in the loop region and target binding domain over the stem region and tail. By introducing this new hairpin-like probe in a conventional GO-based fluorescence platform, we observed both the miRNA-responsive color change by direct observation and sensitive fluorescence increase even below the nanomolar levels in a single solution without an additional separation step.


Assuntos
Colorimetria/métodos , Grafite/química , MicroRNAs/análise , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Células Hep G2 , Humanos , Limite de Detecção
8.
Nucleic Acids Res ; 45(20): 11643-11657, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28977425

RESUMO

Hypoxia increases both active and repressive histone methylation levels via decreased activity of histone demethylases. However, how such increases coordinately regulate induction or repression of hypoxia-responsive genes is largely unknown. Here, we profiled active and repressive histone tri-methylations (H3K4me3, H3K9me3, and H3K27me3) and analyzed gene expression profiles in human adipocyte-derived stem cells under hypoxia. We identified differentially expressed genes (DEGs) and differentially methylated genes (DMGs) by hypoxia and clustered the DEGs and DMGs into four major groups. We found that each group of DEGs was predominantly associated with alterations in only one type among the three histone tri-methylations. Moreover, the four groups of DEGs were associated with different TFs and localization patterns of their predominant types of H3K4me3, H3K9me3 and H3K27me3. Our results suggest that the association of altered gene expression with prominent single-type histone tri-methylations characterized by different localization patterns and with different sets of TFs contributes to regulation of particular sets of genes, which can serve as a model for coordinated epigenetic regulation of gene expression under hypoxia.


Assuntos
Hipóxia Celular/fisiologia , Epigênese Genética/genética , Código das Histonas/genética , Histonas/metabolismo , Células-Tronco/metabolismo , Tecido Adiposo/citologia , Linhagem Celular , Expressão Gênica/genética , Regulação da Expressão Gênica , Humanos , Metilação , Oxigênio/metabolismo , RNA Mensageiro/genética , Células-Tronco/citologia
9.
J Korean Med Sci ; 33(53): e298, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30595680

RESUMO

BACKGROUND: The renal function of individuals is one of the reasons for the variations in therapeutic response to various drugs. Patients with renal impairment are often exposed to drug toxicity, even with drugs that are usually eliminated by hepatic metabolism. Previous study has reported an increased plasma concentration of indoxyl sulfate and decreased plasma concentration of 4ß-hydroxy (OH)-cholesterol in stable kidney transplant recipients, implicating indoxyl sulfate as a cytochrome P450 (CYP) inhibiting factor. In this study, we aimed to evaluate the impact of renal impairment severity-dependent accumulation of indoxyl sulfate on hepatic CYP3A activity using metabolic markers. METHODS: Sixty-six subjects were enrolled in this study; based on estimated glomerular filtration rate (eGFR), they were classified as having mild, moderate, or severe renal impairment. The plasma concentration of indoxyl sulfate was quantified using liquid chromatography-mass spectrometry (LC-MS). Urinary and plasma markers (6ß-OH-cortisol/cortisol, 6ß-OH-cortisone/cortisone, 4ß-OH-cholesterol) for hepatic CYP3A activity were quantified using gas chromatography-mass spectrometry (GC-MS). The total plasma concentration of cholesterol was measured using the enzymatic colorimetric assay to calculate the 4ß-OH-cholesterol/cholesterol ratio. The correlation between variables was assessed using Pearson's correlation test. RESULTS: There was a significant negative correlation between MDRD eGFR and indoxyl sulfate levels. The levels of urinary 6ß-OH-cortisol/cortisol and 6ß-OH-cortisone/cortisone as well as plasma 4ß-OH-cholesterol and 4ß-OH-cholesterol/cholesterol were not correlated with MDRD eGFR and the plasma concentration of indoxyl sulfate. CONCLUSION: Hepatic CYP3A activity may not be affected by renal impairment-induced accumulation of plasma indoxyl sulfate.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Fígado/metabolismo , Insuficiência Renal/patologia , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/urina , Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Cortisona/química , Cortisona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Taxa de Filtração Glomerular , Humanos , Hidrocortisona/química , Hidrocortisona/urina , Indicã/sangue , Rim/metabolismo , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Insuficiência Renal/metabolismo , Índice de Gravidade de Doença
10.
J Korean Med Sci ; 33(9): e58, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29441737

RESUMO

BACKGROUND: In 2011, two roads in a residential area in Seoul were found to be contaminated with the radionuclide cesium-137 (137Cs). In response to public concerns, an epidemiological study was conducted. METHODS: The standardized cancer incidence ratios in the affected and neighboring regions were calculated based on the central cancer registry. Households in the region were sampled using the random stratified sampling technique, and questionnaires were administered to family members, via home visit and via students in elementary to high schools. Information on duration of residency and frequency of use of the roads was applied to calculate cumulative radiation exposure dose from the roads, alongside with the reported 137Cs contamination amounts. Information on past medical history, perceived risk, anxiety and psychological stress was also obtained. Of the 31,053 residents, 8,875 were analyzed. To examine possible associations between radiation exposure and health problems, logistic regression adjusted for covariates were performed with consideration of the sampling design, population weight and stratification. RESULTS: No significant association was found between self-informed diseases, including cancers, and estimated radiation exposure dose. According to an increase of radiation level, a significant increase in anxiety in all and a decline in the psychosocial wellbeing of the adults was noted. The risk perception level was higher in the elderly, females, the less educated, and the highest exposed individuals. CONCLUSION: This study provides a basis for risk communication with residents and community environmental health policy.


Assuntos
Exposição à Radiação , Adolescente , Adulto , Idoso , Radioisótopos de Césio/química , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Saúde Mental , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/etiologia , Exposição à Radiação/efeitos adversos , Medição de Risco , Adulto Jovem
11.
AAPS J ; 26(3): 56, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671158

RESUMO

Advair Diskus is an essential treatment for asthma and chronic obstructive pulmonary disease. It is a dry powder inhaler with a combination of fluticasone propionate (FP) and salmeterol xinafoate (SX). However, the pharmacokinetics (PK) batch-to-batch variability of the reference-listed drug (RLD) hindered its generic product development. This work developed the PK models for inhaled FP and SX that could represent potential batch variability. Two batches each of the reference and the test product (R1, R2, T1, T2) of Advair Diskus (100 µg FP/50 µg SX inhalation) were administered to 60 healthy subjects in a 4-period, 4-sequence crossover study. The failure of the bioequivalence (BE) between R1 and R2 confirmed the high between-batch variability of the RLD. Non-linear mixed effect modeling was used to estimate the population mean PK parameters for each batch. For FP, a 2-compartment model with a sequential dual zero-order absorption best described the PK profile. For SX, a 2-compartment model with a first-order absorption model best fit the data. Both models were able to capture the plasma concentration, the maximum concentration, and the total exposure (AUCinf) adequately for each batch, which could be used to simulate the BE study in the future. In vitro properties were also measured for each batch, and the batch with a higher fraction of the fine particle (diameter < 1 µm, < 2 µm) had a higher AUCinf. This positive correlation for both FP and SX could potentially assist the batch selection for the PK BE study.


Assuntos
Broncodilatadores , Estudos Cross-Over , Inaladores de Pó Seco , Combinação Fluticasona-Salmeterol , Modelos Biológicos , Equivalência Terapêutica , Humanos , Administração por Inalação , Masculino , Adulto , Combinação Fluticasona-Salmeterol/farmacocinética , Combinação Fluticasona-Salmeterol/administração & dosagem , Adulto Jovem , Broncodilatadores/farmacocinética , Broncodilatadores/administração & dosagem , Broncodilatadores/sangue , Feminino , Pessoa de Meia-Idade , Fluticasona/farmacocinética , Fluticasona/administração & dosagem , Xinafoato de Salmeterol/farmacocinética , Xinafoato de Salmeterol/administração & dosagem , Voluntários Saudáveis
12.
Int Immunopharmacol ; 130: 111706, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38382265

RESUMO

BACKGROUND: YH35324, a long-acting IgETrap-Fc fusion protein, is a novel therapeutic agent for immunoglobulin E (IgE)-mediated allergic diseases. This randomized, double-blind, placebo/active-controlled, single ascending dose Phase 1 study assessed the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of YH35324 in subjects with atopy. METHODS: Eligible subjects were healthy subjects or atopic adults with mild allergic rhinitis, atopic dermatitis, food allergy, or urticaria, and a serum total IgE level of 30-700 IU/mL (Part A) or > 700 IU/mL (Part B). In Part A, 35 subjects in 5 cohorts received YH35324 (0.3, 1, 3, 6, and 9 mg/kg), 8 received omalizumab (300 mg), and 9 received placebo. In Part B, 8 subjects received YH35324 and 8 received omalizumab. RESULTS: Twenty subjects (38.5 %) in Part A (YH35324: 37.1 %, omalizumab: 50.0 %, placebo: 33.3 %) and 10 subjects (62.5 %) in Part B (YH35324: 100 %; omalizumab: 25.0 %) experienced treatment-emergent adverse events (TEAEs). TEAEs were mostly grade 1/2; no serious AEs, AE-related treatment discontinuation, or anaphylaxis were reported. YH35324 exhibited dose-proportional increase in Cmax and AUClast over the dose range of 0.3-9 mg/kg. YH35324 rapidly suppressed serum-free IgE levels to a significant extent (< 25 and < 82.8 ng/mL, both P < 0.05) and with longer duration than omalizumab. CONCLUSION: This study showed that YH35324 has a favorable safety profile and is effective in reducing serum-free IgE levels in subjects with atopic conditions.


Assuntos
Anafilaxia , Dermatite Atópica , Adulto , Humanos , Omalizumab/efeitos adversos , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Anafilaxia/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/induzido quimicamente , Imunoglobulina E , Método Duplo-Cego , Ligante de CD40
13.
Food Res Int ; 167: 112665, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087250

RESUMO

Bacteriophages, bacterial viruses, are now being re-highlighted as one of the promising alternative antimicrobial agents to control bacterial pathogens in various fields, including the food industry. However, wild-type (WT) phages isolated from nature are vulnerable to external stresses such as heat, limiting the usability of phages in thermal processing. Here, we applied an adaptive laboratory evolution approach to improving the heat stability of newly isolated Salmonella-infecting lytic phage ΦYMFM0293 and examined its application in the poultry scalding process. After 15 cycles of exposure to sub-lethal temperature, the obtained adaptively evolved (AE) phages maintained approximately 3-log more infectious particles at 73 or 74 °C than the WT and non-heat-treated control phages. Missense mutations mainly concentrated in the genes related to the phage tail module were identified from the independently obtained heat-challenged phages, regardless of host Salmonella's heat-shock protein chaperone induction. These results demonstrated the necessity and sufficiency of the phage exposures to heat for thermal adaptation and suggested the involvement of the phage tail in heat stability. No significant physiological or morphological changes except the mutually offsetting phage replication parameters were observed in the AE phages. Accordingly, hot water supplemented with the AE phages significantly reduced the number of artificially contaminated Salmonella cells on chicken and duck skin in the mimicked scalding process. The AE strategy used here could be applied to other WT phages to improve their usability as more feasible antimicrobials for food safety.


Assuntos
Anti-Infecciosos , Bacteriófagos , Animais , Bacteriófagos/genética , Aves Domésticas , Salmonella , Galinhas , Inocuidade dos Alimentos/métodos
14.
Anal Chim Acta ; 1239: 340708, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36628715

RESUMO

Developing a ready-to-use miniaturized thermosensor is a great challenge due to its individual use on a large scale for daily business such as food industry and healthcare. Herein, a polyethylene glycol (PEG)-modified graphene oxide (GO)-based hydrogel thermosensor was established with a fluorescent dye-labeled peptide nucleic acid (F-PNA). The size-tunable hydrogel with high water content and sufficient solidity allowed free movement of the oligonucleotides through the pores and improved usability for handling the sensor. In the PEG-GO hydrogel, the DNA/F-PNA duplex could be denatured by increasing the temperature, followed by selective PNA capture on the PEG-GO. Using this principle, the PEG-GO hydrogel exhibited a change in the fluorescence signal of F-PNA in a temperature-dependent manner, allowing real-time visualization of temperature on a large scale. The temperature detection range of this system can be adjusted by designing the PNA strands based on the melting temperature of the DNAzyme/PNA duplex. Its sensing specificity and detection range could be increased and broadened by observing multi-color detection using PNA probes labeled with different fluorescent dyes of different lengths in a single hydrogel. In addition, the hydrogel platform is easy to store for long time periods via dehydration and can be restored with the addition of water, allowing easy transport, storage, and use of the thermosensor in everyday life.


Assuntos
Ácidos Nucleicos Peptídicos , Ácidos Nucleicos Peptídicos/química , Hidrogéis , Água , Polietilenoglicóis/química , Hibridização de Ácido Nucleico
15.
Org Lett ; 25(24): 4445-4450, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37310879

RESUMO

This study presents a DNA-compatible synthesis of diverse 5-arylimidazo[1,2-a]pyridin-3-amine derivatives using the Suzuki-Miyaura reaction, followed by a Groebke-Blackburn-Bienaymé (GBB) reaction. The GBB reaction demonstrates a wide substrate scope, mild one-pot reaction conditions, and compatibility with subsequent enzymatic ligation, highlighting its potential in DNA-encoded library technology.


Assuntos
Aminas , DNA , Ciclização , Biblioteca Gênica , Piridinas/síntese química , Piridinas/química
16.
Analyst ; 137(9): 2024-6, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22413127

RESUMO

A new assay platform for DNA exonuclease activity is developed based on the preferential binding of single-stranded DNA (ssDNA) over double-stranded DNA (dsDNA) to graphene oxide. This approach allows a simple and quantitative activity measurement in a short time at low cost.


Assuntos
Ensaios Enzimáticos/métodos , Exodesoxirribonucleases/metabolismo , Fluorometria/métodos , Grafite/química , Óxidos/química , Sequência de Bases , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Nanoestruturas/química , Especificidade por Substrato , Fatores de Tempo
17.
Int J Soc Robot ; 14(1): 193-211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33841588

RESUMO

Is it true that parents always prioritize educational effectiveness when selecting childcare services? The current study identified the potential requirements of dual-income parents toward social robots' diverse childcare functions (e.g., socialization, education, entertainment, and consultation). The results revealed that parental attitudes toward robots were made more positive by all the childcare functions of robots except for their educational features. Furthermore, parents' expectations of childcare functions varied based on their parenting characteristics. Spectral clustering analysis identified distinctive parenting styles (e.g., family-oriented, work-oriented, noninterventional, and dominant), and multigroup structural equation modeling suggested that the impact of robots' socialization function was significant in all parent groups, while other childcare functions exerted limited influence according to specific parenting styles. In addition, children's characteristics were found to alter parents' preferences for each childcare function. These results offer practical implications for the early adoption of childcare robots through predetermining parents' acceptability based on their specific parenting characteristics.

18.
RSC Adv ; 12(25): 15652-15657, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35685716

RESUMO

Biomolecule detection based on the localized surface plasmon resonance (LSPR) phenomenon has advantages in label-free detection, good sensitivity, and measurement simplicity and reproducibility. However, in order to ultimately be used for actual diagnosis, the ability to detect trace amounts of biomarkers is necessary, which requires the development of signal enhancement strategies that enable ultrasensitive detection. In this paper, we provide a straightforward and efficient route to boost LSPR sensitivity based on multiple sample washings. We found that repeated washing and drying cycles lead to a shift in the LSPR peak in a concentration-dependent manner, where this process drives the accumulation of a precipitate, formed by an enzyme reaction with target specificity, in the sample's LSPR active plasmonic nano-valley structure. Results show that the washing and drying process leads to a signal enhancement of more 200 times compared to a sensor with only enzyme-based amplification. To maximize this effect, optimization of the plasmonic nanostructure was also carried out to finally achieve atto-molar detection of miRNA with a distinguishable LSPR peak shift.

19.
AAPS J ; 24(5): 98, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056223

RESUMO

Accurately predicting the spread of the SARS-CoV-2, the cause of the COVID-19 pandemic, is of great value for global regulatory authorities to overcome a number of challenges including medication shortage, outcome of vaccination, and control strategies planning. Modeling methods that are used to simulate and predict the spread of COVID-19 include compartmental model, structured metapopulations, agent-based networks, deep learning, and complex network, with compartmental modeling as one of the most widely used methods. Compartmental model has two noteworthy features, a flexible framework that allows users to easily customize the model structure and its high adaptivity that allows well-matured approaches (e.g., Bayesian inference and mixed-effects modeling) to improve parameter estimation. We retrospectively evaluated the prediction performances of the compartmental models on the CDC COVID-19 Mathematical Modeling webpage based on data collected between August 2020 and February 2021, and subsequently discussed in detail their corresponding model enhancement. Finally, we presented examples using the compartmental models to assist policymaking. By evaluating all models in parallel, we systemically evaluated the performance and evolution of using compartmental models for COVID-19 pandemic prediction. In summary, as a 100-year-old epidemic approach, the compartmental model presents a powerful tool that is extremely adaptive and can be readily customized and implemented to address new data or emerging needs during a pandemic.


Assuntos
COVID-19 , Idoso de 80 Anos ou mais , Teorema de Bayes , COVID-19/epidemiologia , Surtos de Doenças , Modelos Epidemiológicos , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
20.
J Hazard Mater ; 424(Pt B): 127524, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34879518

RESUMO

The chemiresistive response of metal-oxide gas sensors depends on ambient conditions. Humidity is a strongly influential parameter and causes large deviations in signals and, consequently, an inaccurate detection of target gases. Developing sensors unaffected by humidity, as documented by extensive works of research, comes at the cost of response - a significant drop in sensor response inevitably accompanies an increase in humidity-independence. This trade-off between humidity-independence and gas response is one of the major obstacles that limit practical applications of metal-oxide gas sensors. This study presents a novel approach to improve both the features by incorporating the rare-earth element, yttrium, into the host SnO2 sensor. The Y-doped SnO2 nanofibers are highly stable across relative humidity values ranging from 0% to 87%, and show improved selectivity and sensitivity in the detection of up to 20 ppb of NO2 target gas with the limit of detection at 103.71 ppt. Based on experimental results and van der Waals (vdW)-corrected DFT calculations, these improvements can be attributed to the synergistic effect of oxygen vacancy created by the introduction of aliovalent Y and the formation of Y2O3 nanoparticles that play a critical role in making the sensor surface hydrophobic.

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