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1.
Mol Cell ; 70(5): 920-935.e7, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29883609

RESUMO

Receptor-interacting protein kinase-3 (RIP3 or RIPK3) is a central protein in necroptosis, but posttranslational processes that regulate RIP3 activity and stability remain poorly understood. Here, we identify pellino E3 ubiquitin protein ligase 1 (PELI1) as an E3 ligase that targets RIP3 for proteasome-dependent degradation. Phosphorylation of RIP3 on T182 leads to interaction with the forkhead-associated (FHA) domain of PELI1 and PELI1-mediated K48-linked polyubiquitylation of RIP3 on K363. This same phosphorylation event is also important for RIP3 kinase activity; thus, PELI1 preferentially targets kinase-active RIP3 for degradation. PELI1-mediated RIP3 degradation effectively prevents cell death triggered by RIP3 hyperactivation. Importantly, upregulated RIP3 expression in keratinocytes from toxic epidermal necrolysis (TEN) patients is correlated with low expression of PELI1, suggesting that loss of PELI1 may play a role in the pathogenesis of TEN. We propose that PELI1 may function to control inadvertent activation of RIP3, thus preventing aberrant cell death and maintaining cellular homeostasis.


Assuntos
Queratinócitos/enzimologia , Proteínas Nucleares/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Síndrome de Stevens-Johnson/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Morte Celular , Fibroblastos/enzimologia , Fibroblastos/patologia , Células HEK293 , Células HT29 , Células HeLa , Humanos , Queratinócitos/patologia , Camundongos , Proteínas Nucleares/genética , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteólise , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais , Síndrome de Stevens-Johnson/genética , Síndrome de Stevens-Johnson/patologia , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
2.
Nucleic Acids Res ; 52(9): 5088-5106, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38412240

RESUMO

Exploring the connection between ubiquitin-like modifiers (ULMs) and the DNA damage response (DDR), we employed several advanced DNA damage and repair assay techniques and identified a crucial role for LC3B. Notably, its RNA recognition motif (RRM) plays a pivotal role in the context of transcription-associated homologous recombination (HR) repair (TA-HRR), a particular subset of HRR pathways. Surprisingly, independent of autophagy flux, LC3B interacts directly with R-loops at DNA lesions within transcriptionally active sites via its RRM, promoting TA-HRR. Using native RNA immunoprecipitation (nRIP) coupled with high-throughput sequencing (nRIP-seq), we discovered that LC3B also directly interacts with the 3'UTR AU-rich elements (AREs) of BRCA1 via its RRM, influencing its stability. This suggests that LC3B regulates TA-HRR both proximal to and distal from DNA lesions. Data from our LC3B depletion experiments showed that LC3B knockdown disrupts end-resection for TA-HRR, redirecting it towards the non-homologous end joining (NHEJ) pathway and leading to chromosomal instability, as evidenced by alterations in sister chromatid exchange (SCE) and interchromosomal fusion (ICF). Thus, our findings unveil autophagy-independent functions of LC3B in DNA damage and repair pathways, highlighting its importance. This could reshape our understanding of TA-HRR and the interaction between autophagy and DDR.


Assuntos
Proteína BRCA1 , Proteínas Associadas aos Microtúbulos , Estruturas R-Loop , Reparo de DNA por Recombinação , Transcrição Gênica , Humanos , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Dano ao DNA , Reparo do DNA por Junção de Extremidades , Regiões 3' não Traduzidas , Recombinação Homóloga , Linhagem Celular Tumoral , Troca de Cromátide Irmã
3.
Nucleic Acids Res ; 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39217466

RESUMO

PARP inhibitors (PARPi) show selective efficacy in tumors with homologous recombination repair (HRR)-defects but the activation mechanism of HRR pathway in PARPi-treated cells remains enigmatic. To unveil it, we searched for the mediator bridging PARP1 to ATM pathways by screening 211 human ubiquitin-related proteins. We discovered TRIM44 as a crucial mediator that recruits the MRN complex to damaged chromatin, independent of PARP1 activity. TRIM44 binds PARP1 and regulates the ubiquitination-PARylation balance of PARP1, which facilitates timely recruitment of the MRN complex for DSB repair. Upon exposure to PARPi, TRIM44 shifts its binding from PARP1 to the MRN complex via its ZnF UBP domain. Knockdown of TRIM44 in cells significantly enhances the sensitivity to olaparib and overcomes the resistance to olaparib induced by 53BP1 deficiency. These observations emphasize the central role of TRIM44 in tethering PARP1 to the ATM-mediated repair pathway. Suppression of TRIM44 may enhance PARPi effectiveness and broaden their use even to HR-proficient tumors.

4.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38233089

RESUMO

With the recent advent of single-cell level biological understanding, a growing interest is in identifying cell states or subtypes that are homogeneous in terms of gene expression and are also enriched in certain biological conditions, including disease samples versus normal samples (condition-specific cell subtype). Despite the importance of identifying condition-specific cell subtypes, existing methods have the following limitations: since they train models separately between gene expression and the biological condition information, (1) they do not consider potential interactions between them, and (2) the weights from both types of information are not properly controlled. Also, (3) they do not consider non-linear relationships in the gene expression and the biological condition. To address the limitations and accurately identify such condition-specific cell subtypes, we develop scDeepJointClust, the first method that jointly trains both types of information via a deep neural network. scDeepJointClust incorporates results from the power of state-of-the-art gene-expression-based clustering methods as an input, incorporating their sophistication and accuracy. We evaluated scDeepJointClust on both simulation data in diverse scenarios and biological data of different diseases (melanoma and non-small-cell lung cancer) and showed that scDeepJointClust outperforms existing methods in terms of sensitivity and specificity. scDeepJointClust exhibits significant promise in advancing our understanding of cellular states and their implications in complex biological systems.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/genética , Redes Neurais de Computação
5.
Am J Respir Crit Care Med ; 210(3): 343-351, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38564365

RESUMO

Rationale: Observational studies suggest that high-dose isoniazid may be efficacious in treating multidrug-resistant tuberculosis. However, its activity against Mycobacterium tuberculosis (M.tb) with katG mutations (which typically confer high-level resistance) is not established. Objectives: To characterize the early bactericidal activity (EBA) of high-dose isoniazid in patients with tuberculosis caused by katG-mutated M.tb. Methods: A5312 was a phase IIA randomized, open-label trial. Participants with tuberculosis caused by katG-mutated M.tb were randomized to receive 15 or 20 mg/kg isoniazid daily for 7 days. Daily sputum samples were collected for quantitative culture. Intensive pharmacokinetic sampling was performed on Day 6. Data were pooled across all A5312 participants for analysis (drug-sensitive, inhA-mutated, and katG-mutated M.tb). EBA was determined using nonlinear mixed-effects modeling. Measurements and Main Results: Of 80 treated participants, 21 had katG-mutated M.tb. Isoniazid pharmacokinetics were best described by a two-compartment model with an effect of NAT2 acetylator phenotype on clearance. Model-derived maximum concentration and area under the concentration-time curve in the 15 and 20 mg/kg groups were 15.0 and 22.1 mg/L and 57.6 and 76.8 mg ⋅ h/L, respectively. Isoniazid bacterial kill was described using an effect compartment and a sigmoidal maximum efficacy relationship. Isoniazid potency against katG-mutated M.tb was approximately 10-fold lower than in inhA-mutated M.tb. The highest dose of 20 mg/kg did not demonstrate measurable EBA, except against a subset of slow NAT2 acetylators (who experienced the highest concentrations). There were no grade 3 or higher drug-related adverse events. Conclusions: This study found negligible bactericidal activity of high-dose isoniazid (15-20 mg/kg) in the majority of participants with tuberculosis caused by katG-mutated M.tb. Clinical trial registered with www.clinicaltrials.gov (NCT01936831).


Assuntos
Antituberculosos , Proteínas de Bactérias , Isoniazida , Mutação , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Isoniazida/farmacocinética , Isoniazida/administração & dosagem , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Humanos , Antituberculosos/farmacocinética , Antituberculosos/administração & dosagem , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Feminino , Masculino , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Adulto , Pessoa de Meia-Idade , Proteínas de Bactérias/genética , Catalase/genética , Relação Dose-Resposta a Droga , Idoso , Testes de Sensibilidade Microbiana
6.
Proc Natl Acad Sci U S A ; 119(30): e2206588119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35867821

RESUMO

Oncogenic mutations within the epidermal growth factor receptor (EGFR) are found in 15 to 30% of all non-small-cell lung carcinomas. The term exon 19 deletion (ex19del) is collectively used to refer to more than 20 distinct genomic alterations within exon 19 that comprise the most common EGFR mutation subtype in lung cancer. Despite this heterogeneity, clinical treatment decisions are made irrespective of which EGFR ex19del variant is present within the tumor, and there is a paucity of information regarding how individual ex19del variants influence protein structure and function. Herein, we identified allele-specific functional differences among ex19del variants attributable to recurring sequence and structure motifs. We built all-atom structural models of 60 ex19del variants identified in patients and combined molecular dynamics simulations with biochemical and biophysical experiments to analyze three ex19del mutations (E746_A750, E746_S752 > V, and L747_A750 > P). We demonstrate that sequence variation in ex19del alters oncogenic cell growth, dimerization propensity, enzyme kinetics, and tyrosine kinase inhibitor (TKI) sensitivity. We show that in contrast to E746_A750 and E746_S752 > V, the L747_A750 > P variant forms highly active ligand-independent dimers. Enzyme kinetic analysis and TKI inhibition experiments suggest that E746_S752 > V and L747_A750 > P display reduced TKI sensitivity due to decreased adenosine 5'-triphosphate Km. Through these analyses, we propose an expanded framework for interpreting ex19del variants and considerations for therapeutic intervention.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Éxons , Neoplasias Pulmonares , Alelos , Motivos de Aminoácidos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ativação Enzimática/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Receptores ErbB/genética , Éxons/genética , Humanos , Cinética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Recidiva Local de Neoplasia/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Deleção de Sequência
7.
J Allergy Clin Immunol ; 153(1): 122-131, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37742934

RESUMO

BACKGROUND: Little is known about nasal epithelial gene expression and total IgE in youth. OBJECTIVE: We aimed to identify genes whose nasal epithelial expression differs by total IgE in youth, and group them into modules that could be mapped to airway epithelial cell types. METHODS: We conducted a transcriptome-wide association study of total IgE in 469 Puerto Ricans aged 9 to 20 years who participated in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study, separately in all subjects and in those with asthma. We then attempted to replicate top findings for each analysis using data from 3 cohorts. Genes with a Benjamini-Hochberg-adjusted P value of less than .05 in the Epigenetic Variation and Childhood Asthma in Puerto Ricans study and a P value of less than .05 in the same direction of association in 1 or more replication cohort were considered differentially expressed genes (DEGs). DEGs for total IgE in subjects with asthma were further dissected into gene modules using coexpression analysis, and such modules were mapped to specific cell types in airway epithelia using public single-cell RNA-sequencing data. RESULTS: A higher number of DEGs for total IgE were identified in subjects with asthma (n = 1179 DEGs) than in all subjects (n = 631 DEGs). In subjects with asthma, DEGs were mapped to 11 gene modules. The top module for positive correlation with total IgE was mapped to myoepithelial and mucus secretory cells in lower airway epithelia and was regulated by IL-4, IL5, IL-13, and IL-33. Within this module, hub genes included CDH26, FETUB, NTRK2, CCBL1, CST1, and CST2. Furthermore, an enrichment analysis showed overrepresentation of genes in signaling pathways for synaptogenesis, IL-13, and ferroptosis, supporting interactions between interleukin- and acetylcholine-induced responses. CONCLUSIONS: Our findings for nasal epithelial gene expression support neuroimmune coregulation of total IgE in youth with asthma.


Assuntos
Asma , Interleucina-13 , Criança , Humanos , Adolescente , Interleucina-13/genética , Nariz , Transcriptoma , Imunoglobulina E
8.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619226

RESUMO

Halide perovskite-based resistive switching memory (memristor) has potential in an artificial synapse. However, an abrupt switch behavior observed for a formamidinium lead triiodide (FAPbI3)-based memristor is undesirable for an artificial synapse. Here, we report on the δ-FAPbI3/atomic-layer-deposited (ALD)-SnO2 bilayer memristor for gradual analogue resistive switching. In comparison to a single-layer δ-FAPbI3 memristor, the heterojunction δ-FAPbI3/ALD-SnO2 bilayer effectively reduces the current level in the high-resistance state. The analog resistive switching characteristics of δ-FAPbI3/ALD-SnO2 demonstrate exceptional linearity and potentiation/depression performance, resembling an artificial synapse for neuromorphic computing. The nonlinearity of long-term potentiation and long-term depression is notably decreased from 12.26 to 0.60 and from -8.79 to -3.47, respectively. Moreover, the δ-FAPbI3/ALD-SnO2 bilayer achieves a recognition rate of ≤94.04% based on the modified National Institute of Standards and Technology database (MNIST), establishing its potential in an efficient artificial synapse.

9.
J Biol Chem ; 299(7): 104914, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37315787

RESUMO

The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) commonly targeted for inhibition by anticancer therapeutics. Current therapeutics target EGFR's kinase domain or extracellular region. However, these types of inhibitors are not specific for tumors over healthy tissue and therefore cause undesirable side effects. Our lab has recently developed a new strategy to regulate RTK activity by designing a peptide that specifically binds to the transmembrane (TM) region of the RTK to allosterically modify kinase activity. These peptides are acidity-responsive, allowing them to preferentially target acidic environments like tumors. We have applied this strategy to EGFR and created the PET1 peptide. We observed that PET1 behaves as a pH-responsive peptide that modulates the configuration of the EGFR TM through a direct interaction. Our data indicated that PET1 inhibits EGFR-mediated cell migration. Finally, we investigated the mechanism of inhibition through molecular dynamics simulations, which showed that PET1 sits between the two EGFR TM helices; this molecular mechanism was additionally supported by AlphaFold-Multimer predictions. We propose that the PET1-induced disruption of native TM interactions disturbs the conformation of the kinase domain in such a way that it inhibits EGFR's ability to send migratory cell signals. This study is a proof-of-concept that acidity-responsive membrane peptide ligands can be generally applied to RTKs. In addition, PET1 constitutes a viable approach to therapeutically target the TM of EGFR.


Assuntos
Regulação Alostérica , Membrana Celular , Receptores ErbB , Peptídeos , Humanos , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Receptores ErbB/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Estrutura Secundária de Proteína/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/metabolismo , Regulação Alostérica/efeitos dos fármacos , Membrana Celular/química , Membrana Celular/metabolismo , Concentração de Íons de Hidrogênio , Peptídeos/farmacologia , Movimento Celular/efeitos dos fármacos , Domínios Proteicos/efeitos dos fármacos , Antineoplásicos/farmacologia
10.
Br J Nutr ; 132(2): 141-150, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804177

RESUMO

The Dietary Approaches to Stop Hypertension (DASH) diet is highly effective in controlling blood pressure (BP). Although Na restriction is not a primary focus within the DASH diet, it is recommended that it be added to control BP. Therefore, we aimed to systematically review the characteristics and BP-lowering effects of Na-restricted DASH diet interventions. We searched thirteen databases, namely, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, KoreaMed, KISS, KMbase, RISS, CINAHL, Scopus, ClinicalTrials.gov, Grey Literature Report, OpenGrey and PQDT Global, for articles published through May 2023. The randomised controlled trials assessing the BP-lowering effect of the Na-restricted DASH diet in adults aged 18 years and older were included. The study protocol was registered in the PROSPERO registry (CRD42023409996). The risk of bias in the included studies was also assessed. Nine articles were included in this review. Interventions were categorised into three types: feeding, provision and education, and the study results were compared by intervention type. BP was significantly reduced in two of the three feeding studies, one of the three provisional studies and none of the educational studies. In eight studies, effect sizes varied among both systolic BP (-7·7 to -2·4) and diastolic BP (-8·3 to 0·1). Six studies showed an overall high risk of bias. In conclusion, Na-restricted DASH may have beneficial effects on BP control. Additionally, compared with control interventions, feeding interventions appeared to have a greater BP-lowering effect. Further high-quality studies are needed to improve the quality of the evidence.


Assuntos
Pressão Sanguínea , Dieta Hipossódica , Abordagens Dietéticas para Conter a Hipertensão , Hipertensão , Humanos , Abordagens Dietéticas para Conter a Hipertensão/métodos , Hipertensão/dietoterapia , Hipertensão/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
11.
Inorg Chem ; 63(32): 15044-15052, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39074868

RESUMO

Two o-carboranes with (i) 9,9-dimethyl-9H-xanthene and (ii) spiro[fluorene-9,9'-xanthene] moieties (XTC and sXTC, respectively) were prepared and characterized. Single X-ray crystallography analysis revealed the presence of intermolecular hydrogen bonds in XTC crystals. Although both compounds did not exhibit emission in tetrahydrofuran solutions at 298 K, intense bluish emission was observed in the solid states and frozen tetrahydrofuran solutions at 77 K. According to the results of theoretical calculations, this emission originated from an intramolecular charge transfer (ICT) transition with the o-carborane moiety. The absolute quantum efficiency (Φem) of the ICT-based emission in the film state equaled 49% for XTC and 20% for sXTC but was as high as 90% for the crystals of both compounds. The crystal structures of XTC and sXTC revealed that the o-carboranyl-appended phenyl plane was orthogonal (85-89°) to the carbon-carbon bonding axis in the o-carborane, indicating the existence of a strong exo-π-interaction, which was identified as the structural basis for the ICT-based transition. These results implied that the intermolecular structural effect of XTC in the randomly aggregated solid state (film) helped maintain the above orthogonality and, hence, the high efficiency from the ICT radiative mechanism. Thus, we concluded that the ICT radiative efficiency of o-carboranyl luminophores in the aggregated solid state can be controlled by specific intermolecular interactions and that the molecular geometric design inducing this feature can be important for developing highly efficient carboranyl luminophores.

12.
J Toxicol Environ Health A ; 87(9): 371-380, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38440899

RESUMO

Exposure to microplastics may be associated with damage of immune system. Polypropylene microplastics (PP-MPs) with a wide range of beneficial applications have not been extensively studied with respect to the immune system. The aim of this investigation is to examine the influence of two different sizes of PP-MPs (5.2 and 23.9 µm diameter) on immune system components in ICR mice. PP-MPs were administered orally to female and male mice at 0 (corn oil vehicle), 500, 1000, or 2000 mg/kg/d for single and daily for 4-week repeated toxicity test, respectively. No significant differences were observed in number of thymic CD4+, CD8+, CD4+CD8+ T lymphocytes, splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-γ to interleukin-4 in culture supernatants from activated splenocytes ex vivo (48 hr) was lower in females which were repeatedly administered with PP-MPs compared to vehicle irrespective of PP-MPs size and dose. In contrast, the opposite trend was observed in males. Production of tumor necrosis factor-α was upregulated in females that were repeatedly exposed to PP-MPs. The serum IgG2a/IgG1 ratio was lowered in female receiving large-size PP-MPs. Data suggest that immune disturbances resulting in predominant type-2 helper T cell reactivity may occur in mice, especially in females, when repeatedly exposed to PP-MPs. Further investigations with longer exposure periods are necessary to determine the immunotoxicities attributed to PP-MPs.


Assuntos
Microplásticos , Poluentes Químicos da Água , Camundongos , Masculino , Feminino , Animais , Camundongos Endogâmicos ICR , Plásticos , Polipropilenos/toxicidade , Baço
13.
Ecotoxicol Environ Saf ; 276: 116294, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574646

RESUMO

Particulate matter (PM), released into the air by a variety of natural and human activities, is a key indicator of air pollution. Although PM is known as the extensive health hazard to affect a variety of illness, few studies have specifically investigated the effects of PM10 exposure on schizophrenic development. In the present study, we aimed to investigate the impact of PM10 on MK-801, N-methyl-D-aspartate (NMDA) receptor antagonist, induced schizophrenia-like behaviors in C57BL/6 mouse. Preadolescent mice were exposed PM10 to 3.2 mg/m3 concentration for 4 h/day for 2 weeks through a compartmentalized whole-body inhalation chamber. After PM10 exposure, we conducted behavioral tests during adolescence and adulthood to investigate longitudinal development of schizophrenia. We found that PM10 exacerbated schizophrenia-like behavior, such as psychomotor agitation, social interaction deficits and cognitive deficits at adulthood in MK-801-induced schizophrenia animal model. Furthermore, the reduced expression levels of brain-derived neurotrophic factor (BDNF) and the phosphorylation of BDNF related signaling molecules, extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), were exacerbated by PM10 exposure in the adult hippocampus of MK-801-treated mice. Thus, our present study demonstrates that exposure to PM10 in preadolescence exacerbates the cognitive impairment in animal model of schizophrenia, which are considered to be facilitated by the decreased level of BDNF through reduced ERK-CREB expression.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Maleato de Dizocilpina , Camundongos Endogâmicos C57BL , Material Particulado , Esquizofrenia , Transdução de Sinais , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Esquizofrenia/induzido quimicamente , Material Particulado/toxicidade , Maleato de Dizocilpina/farmacologia , Camundongos , Masculino , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Poluentes Atmosféricos/toxicidade , Comportamento Animal/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo
14.
Sensors (Basel) ; 24(16)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39204828

RESUMO

Wireless local area networks (WLANs) have recently evolved into technologies featuring extremely high throughput and ultra-high reliability. As WLANs are predominantly utilized in Internet of Things (IoT) and Wi-Fi-enabled sensor applications powered by coin cell batteries, these high-efficiency, high-performance technologies often cause significant battery depletion. The introduction of the trigger frame-based uplink transmission method, designed to enhance network throughput, lacks adequate security measures, enabling attackers to manipulate trigger frames. Devices receiving such frames must respond immediately; however, if a device receives a fake trigger frame, it fails to enter sleep mode, continuously sending response signals and thereby increasing power consumption. This problem is specifically acute in next-generation devices that support multi-link operation (MLO), capable of simultaneous transmission and reception across multiple links, rendering them more susceptible to battery draining attacks than conventional single-link devices. To address this, this paper introduces a Secure Triggering Frame-Based Dynamic Power Saving Mechanism (STF-DPSM) specifically designed for multi-link environments. Experimental results indicate that even in a multi-link environment with only two links, the STF-DPSM improves energy efficiency by an average of approximately 55.69% over conventional methods and reduces delay times by an average of approximately 44.7% compared with methods that consistently utilize encryption/decryption and integrity checks.

15.
Am J Dent ; 37(5): 223-229, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39321101

RESUMO

PURPOSE: To explore the latest trends in research on whitening toothpaste and to present the issues and future perspectives of these studies. METHODS: An initial PubMed search was performed, followed by a meticulous manual review. A total of 543 papers were initially retrieved, and 54 final research papers were selected and analyzed through a manual review. RESULTS: The number of studies on whitening toothpastes has significantly increased, and while initial studies primarily focused on the efficacy of various whitening toothpastes, recent studies have shifted towards investigating the potential effects on dental hard tissues such as enamel and dentin. Common active ingredients used in these whitening toothpastes include hydrogen peroxide, activated charcoal, and blue covarine. Most studies have used commercial toothpastes with fixed ingredients rather than experimentally manufactured toothpaste, and it was noted that toothpastes from specific major manufacturers were frequently used. CLINICAL SIGNIFICANCE: Whitening toothpastes should be treated as separate entities based on their active ingredients, and more standardized experimental designs are required for better comparisons. Accurate analysis and labeling of other components of toothpaste are also essential.


Assuntos
Clareadores Dentários , Cremes Dentais , Cremes Dentais/química , Humanos , Clareamento Dental/métodos , Peróxido de Hidrogênio , Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Isoindóis , Metaloporfirinas , Pesquisa em Odontologia
16.
Am J Dent ; 37(4): 171-176, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39186595

RESUMO

PURPOSE: To evaluate the impact of coffee attributes on tooth discoloration, emphasizing the importance of potential factors such as serving temperature, bean variety, and chlorogenic acid (CGA) content. METHODS: Coffee preparation involved the extraction of espresso from four types of roasted beans (Vietnam Robusta, Uganda Robusta, Ethiopia Yirgacheffe Arabica, and Colombia Supremo Arabica), followed by chlorogenic content analysis using high-performance liquid chromatography. Bovine tooth enamel specimens were carefully prepared and stained with coffee (hot and iced), with a color assessment conducted at different time intervals (3, 9, 24, 48, and 72 hours). The Vickers hardness tester was employed to ensure specimen quality, while spectrophotometry aided in color analysis using the CIEDE2000 formula. RESULTS: The results revealed varying effects of serving temperature, bean type, and CGA content on tooth discoloration. It was demonstrated that perceptible color differences occur after a 3-hour immersion in coffee, with hot coffee showing higher staining potential compared to iced variations. Furthermore, chlorogenic acid content and bean type significantly affected tooth discoloration, with higher chlorogenic acid levels associated with increased staining. Notably, Robusta coffee showed less discoloration compared to Arabica, potentially due to differences in pH levels. CLINICAL SIGNIFICANCE: The findings provide valuable insights for both dental practitioners and coffee consumers, assisting in making informed decisions regarding coffee intake and oral hygiene.


Assuntos
Ácido Clorogênico , Café , Descoloração de Dente , Café/química , Descoloração de Dente/induzido quimicamente , Ácido Clorogênico/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Cor , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/química , Espectrofotometria , Temperatura
17.
Am J Dent ; 37(1): 3-8, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458975

RESUMO

PURPOSE: To evaluate the effectiveness of whitening toothpaste in restoring tooth color after coffee staining and its potential impact on enamel surfaces compared with regular toothpaste. METHODS: Bovine tooth enamel specimens were prepared and stained with coffee solutions before undergoing brushing simulation with different toothpaste slurries (whitening, regular, reference). For precise evaluation, spectrophotometric measurements were taken at intervals to assess color changes using the CIELAB (Commission Internationale de l'Éclairage Lab*) color space. Additionally, profilometric measurements were taken to determine the impact of toothpaste type on the roughness and abraded depth of the enamel surface. To understand the effects of toothpaste and brushing on color change, surface roughness, and abraded depth, while also considering correlations between these factors, the findings were analyzed using mixed-effects models. RESULTS: The whitening toothpaste group demonstrated the highest recovery rate (71%) after 10,000 brushstrokes, followed by the regular toothpaste group (48%) and the reference slurry group (43%). The mixed-effects model analysis revealed that the reference group had a smaller change in lightness (ΔL) than those in the regular toothpaste group. The whitening toothpaste group showed a greater change in lightness on average than those in the regular toothpaste group, with an increase in lightness as the number of brushstrokes increased. According to the roughness and abraded depth data, the whitening toothpaste group was least affected by brushing, while the reference and regular toothpaste groups showed higher levels of roughness and abraded depth at all intervals. CLINICAL SIGNIFICANCE: Gaining a thorough understanding of the effectiveness of whitening toothpaste and its impact on the enamel surface plays a crucial role in refining toothpaste formulations and advancing tooth whitening techniques in dental care.


Assuntos
Clareamento Dental , Descoloração de Dente , Animais , Bovinos , Humanos , Cremes Dentais/uso terapêutico , Cremes Dentais/farmacologia , Café , Esmalte Dentário , Descoloração de Dente/tratamento farmacológico , Descoloração de Dente/prevenção & controle , Clareamento Dental/métodos , Escovação Dentária , Assistência Odontológica , Cor
18.
J Allergy Clin Immunol ; 152(4): 887-898, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37271320

RESUMO

BACKGROUND: Expression quantitative trait methylation (eQTM) analyses uncover associations between DNA methylation markers and gene expression. Most eQTM analyses of complex diseases have focused on cis-eQTM pairs (within 1 megabase). OBJECTIVES: This study sought to identify cis- and trans-methylation markers associated with gene expression in airway epithelium from youth with and without atopic asthma. METHODS: In this study, the investigators conducted both cis- and trans-eQTM analyses in nasal (airway) epithelial samples from 158 Puerto Rican youth with atopic asthma and 100 control subjects without atopy or asthma. The investigators then attempted to replicate their findings in nasal epithelial samples from 2 studies of children, while also examining whether their results in nasal epithelium overlap with those from an eQTM analysis in white blood cells from the Puerto Rican subjects. RESULTS: This study identified 9,108 cis-eQTM pairs and 2,131,500 trans-eQTM pairs. Trans-associations were significantly enriched for transcription factor and microRNA target genes. Furthermore, significant cytosine-phosphate-guanine sites (CpGs) were differentially methylated in atopic asthma and significant genes were enriched for genes differentially expressed in atopic asthma. In this study, 50.7% to 62.6% of cis- and trans-eQTM pairs identified in Puerto Rican youth were replicated in 2 smaller cohorts at false discovery rate-adjusted P < .1. Replicated genes in the trans-eQTM analysis included biologically plausible asthma-susceptibility genes (eg, HDC, NLRP3, ITGAE, CDH26, and CST1) and are enriched in immune pathways. CONCLUSIONS: Studying both cis- and trans-epigenetic regulation of airway epithelial gene expression can identify potential causal and regulatory pathways or networks for childhood asthma. Trans-eQTM CpGs may regulate gene expression in airway epithelium through effects on transcription factor and microRNA target genes.


Assuntos
Asma , MicroRNAs , Criança , Adolescente , Humanos , Transcriptoma , Epigênese Genética , Asma/metabolismo , Metilação de DNA , Epitélio/metabolismo , Marcadores Genéticos , Mucosa Nasal/metabolismo , Fatores de Transcrição/genética , MicroRNAs/genética , MicroRNAs/metabolismo
19.
Odontology ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904919

RESUMO

The enamel surface may undergo demineralization due to exposure to acidic substances and the remineralization of the etched enamel is crucial to regain or maintain integrity. This study aimed to investigate the erosive effect of 10 acidic solutions on tooth enamel and the remineralization capacity of milk and artificial saliva by measuring surface roughness (Ra), enamel depth, and microhardness. A total of 80 bovine incisor enamel specimens were immersed in 10 different acidic solutions, including four different acidic drinks, three different citric acid solutions, and three different citric acid buffer solutions, for 1 h. After demineralization, the specimens were immersed in milk and artificial saliva for 3 h. Surface roughness, enamel abraded depth, and microhardness were measured before demineralization, in-between time intervals and after remineralization. Data were analyzed using Friedman and Kruskal-Wallis tests (p < 0.05). The results indicate a significant difference in surface roughness between the measurements taken at different time intervals, particularly between the baseline and after 1 h demineralization. Also, the specimens immersed in CAB1 exhibited greatest increase in Ra among other acidic solutions (Δ: 0.18 ± 0.07). Moreover, only the microhardness increased after remineralization (p < 0.05). Enamel demineralization using various acidic solutions revealed increased Ra and enamel abraded depth, and decreased microhardness. The use of remineralization agents, milk and artificial saliva, demonstrated an increase in microhardness. This study provides insights into the effects of different acidic solutions and potential remineralization agents on tooth enamel.

20.
Acta Odontol Scand ; 82(1): 1-8, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37565724

RESUMO

OBJECTIVE: Coffee is one of the most popular beverages in the world, with millions of people consuming it every day. The effect of coffee on teeth discoloration has long been a concern for both coffee drinkers and dental professionals. To address this concern, this study aimed to investigate the role of chlorogenic acids (CGAs) and the type of coffee in coffee-induced teeth discoloration. MATERIALS AND METHODS: High-performance liquid chromatography with a photodiode array detector was used to determine the CGA contents of instant coffee produced by five manufacturers (Starbucks, Dunkin' Donuts, Kanu, Ediya, Coffee Bean). A total of 180 bovine tooth specimens were immersed in the coffee samples for varying durations (3, 9, 24, 48, and 72 h), and the discoloration levels were measured using a spectrophotometer. A linear mixed-effects model analysis was used to determine the significance of L*, a*, and b* values in relation to the duration of coffee immersion and coffee type. RESULTS: Both immersion time and coffee type had significant effects on tooth discoloration (p < 0.001), with some types of coffee being more strongly associated with tooth discoloration than others. The amount of CGAs present in coffee was found to be positively correlated with the degree of discoloration (p = 0.030). CONCLUSIONS: Prolonged exposure to coffee can exacerbate teeth staining, and different types of coffee can cause varying degrees of discoloration. Furthermore, coffee with higher levels of CGAs may lead to greater tooth discoloration.


Assuntos
Descoloração de Dente , Animais , Bovinos , Humanos , Ácido Clorogênico/efeitos adversos , Bebidas , Espectrofotometria , Nucleotidiltransferases , Cor , Teste de Materiais
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