Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 207
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
EMBO Rep ; 24(6): e56319, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-37114473

RESUMO

Vitamins are essential micronutrients, but the mechanisms of vitamin chemoreception in animals are poorly understood. Here, we provide evidence that vitamin C doubles starvation resistance and induces egg laying in Drosophila melanogaster. Our behavioral analyses of genetically engineered and anatomically ablated flies show that fruit flies sense vitamin C via sweet-sensing gustatory receptor neurons (GRNs) in the labellum. Using a behavioral screen and in vivo electrophysiological analyses of ionotropic receptors (IRs) and sweet-sensing gustatory receptors (GRs), we find that two broadly tuned IRs (i.e., IR25a and IR76b) and five GRs (i.e., GR5a, GR61a, GR64b, GR64c, and GR64e) are essential for vitamin C detection. Thus, vitamin C is directly detected by the fly labellum and requires at least two distinct receptor types. Next, we expand our electrophysiological study to test attractive tastants such as sugars, carboxylic acids, and glycerol. Our analysis elucidates the molecular basis of chemoreception in sweet-sensing GRNs.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/fisiologia , Drosophila melanogaster/genética , Paladar/fisiologia , Ácido Ascórbico/farmacologia , Proteínas de Drosophila/genética , Vitaminas , Receptores de Superfície Celular/genética
2.
Chem Rev ; 123(16): 9982-10078, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37542724

RESUMO

Recent advancements in wearable electronics offer seamless integration with the human body for extracting various biophysical and biochemical information for real-time health monitoring, clinical diagnostics, and augmented reality. Enormous efforts have been dedicated to imparting stretchability/flexibility and softness to electronic devices through materials science and structural modifications that enable stable and comfortable integration of these devices with the curvilinear and soft human body. However, the optical properties of these devices are still in the early stages of consideration. By incorporating transparency, visual information from interfacing biological systems can be preserved and utilized for comprehensive clinical diagnosis with image analysis techniques. Additionally, transparency provides optical imperceptibility, alleviating reluctance to wear the device on exposed skin. This review discusses the recent advancement of transparent wearable electronics in a comprehensive way that includes materials, processing, devices, and applications. Materials for transparent wearable electronics are discussed regarding their characteristics, synthesis, and engineering strategies for property enhancements. We also examine bridging techniques for stable integration with the soft human body. Building blocks for wearable electronic systems, including sensors, energy devices, actuators, and displays, are discussed with their mechanisms and performances. Lastly, we summarize the potential applications and conclude with the remaining challenges and prospects.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Eletrônica
3.
Acta Neurochir (Wien) ; 166(1): 34, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38270816

RESUMO

PURPOSE: A consensus on decompressive craniectomy for intracerebral hemorrhage (ICH) has not yet been established. We aimed to investigate the development of shunt-dependent hydrocephalus based on the method of ICH surgery, with a focus on craniectomy. METHODS: We retrospectively enrolled 458 patients with supratentorial ICH who underwent surgical hematoma evacuation between April 2005 and December 2021 at two independent stroke centers. Multivariate analyses were performed to characterize risk factors for postoperative shunt-dependent hydrocephalus. Propensity score matching (1:2) was undertaken to compensate for group-wise imbalances based on probable factors that were suspected to affect the development of hydrocephalus, and the clinical impact of craniectomy on shunt-dependent hydrocephalus was evaluated by the matched analysis. RESULTS: Overall, 43 of the 458 participants (9.4%) underwent shunt procedures as part of the management of hydrocephalus after ICH. Multivariate analysis revealed that intraventricular hemorrhage (IVH) and craniectomy were associated with shunt-dependent hydrocephalus after surgery for ICH. After propensity score matching, there were no statistically significant intergroup differences in participant age, sex, hypertension status, diabetes mellitus status, lesion location, ICH volume, IVH occurrence, or IVH severity. The craniectomy group had a significantly higher incidence of shunt-dependent hydrocephalus than the non-craniectomy group (28.9% vs. 4.3%, p < 0.001; OR 9.1, 95% CI 3.7-22.7), craniotomy group (23.2% vs. 4.3%, p < 0.001; OR 6.6, 95% CI 2.5-17.1), and catheterization group (20.0% vs. 4.0%, p = 0.012; OR 6.0, 95% CI 1.7-21.3). CONCLUSION: Decompressive craniectomy seems to increase shunt-dependent hydrocephalus among patients undergoing surgical ICH evacuation. The decision to perform a craniectomy for patients with ICH should be carefully individualized while considering the risk of hydrocephalus.


Assuntos
Hemorragia Cerebral , Hidrocefalia , Humanos , Pontuação de Propensão , Estudos Retrospectivos , Hemorragia Cerebral/cirurgia , Craniotomia , Hidrocefalia/etiologia , Hidrocefalia/cirurgia
4.
Sensors (Basel) ; 23(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37960637

RESUMO

In this paper, we propose a novel simultaneous Correlative Interferometer (CI) technique that elaborately estimates the Direction of Arrival (DOA) of multiple source signals incident on an antenna array. The basic idea of the proposed technique is that the antenna-array-based receiver compares the phase of the received signal with one of the candidates at each time sample and jointly exploits these multiple time samples to estimate the DOAs of multiple signal sources. The proposed simultaneous CI-based DOA estimation technique collectively utilizes multiple time-domain samples and can be regarded as a generalized version of the conventional CI algorithm for the case of multiple time-domain samples. We first thoroughly review the conventional CI algorithm to comprehensively explain the procedure of the direction-finding algorithm that adopts the phase information of received signals. We also discuss several technical issues of conventional CI-based DOA estimation techniques that are originally proposed for the case of a single time-domain sample. Then, we propose a simultaneous CI-based DOA estimation technique with multi-sample diversity as a novel solution for the case of multiple time-domain samples. We clearly compare the proposed simultaneous CI technique with the conventional CI technique and we compare the existing Multiple Signal Classification (MUSIC)-based DOA estimation technique with the conventional CI-based technique by using the DOA spectrum as well. To the best of our knowledge, the simultaneous CI-based DOA estimation technique that effectively utilizes the characteristics of multiple signal sources over multiple time-domain samples has not been reported in the literature. Through extensive computer simulations, we show that the proposed simultaneous CI technique significantly outperforms both the conventional CI technique in terms of DOA estimation even in harsh environments and with various antenna array structures. It is worth noting that the proposed simultaneous CI technique results in much better performance than the classical MUSIC algorithm, which is one of the most representative subspace-based DOA estimation techniques.

5.
Sensors (Basel) ; 23(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36904724

RESUMO

The importance of monitoring the electron density uniformity of plasma has attracted significant attention in material processing, with the goal of improving production yield. This paper presents a non-invasive microwave probe for in-situ monitoring electron density uniformity, called the Tele-measurement of plasma Uniformity via Surface wave Information (TUSI) probe. The TUSI probe consists of eight non-invasive antennae and each antenna estimates electron density above the antenna by measuring the surface wave resonance frequency in a reflection microwave frequency spectrum (S11). The estimated densities provide electron density uniformity. For demonstration, we compared it with the precise microwave probe and results revealed that the TUSI probe can monitor plasma uniformity. Furthermore, we demonstrated the operation of the TUSI probe beneath a quartz or wafer. In conclusion, the demonstration results indicated that the TUSI probe can be used as an instrument for a non-invasive in-situ method for measuring electron density uniformity.

6.
Nano Lett ; 22(1): 524-532, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34665632

RESUMO

The worldwide proliferation of COVID-19 poses the urgent need for sterilizable and transparent air filters to inhibit virus transmission while retaining ease of communication. Here, we introduce copper nanowires to fabricate transparent and self-sterilizable air filters. Copper nanowire air filter (CNAF) allowed visible light penetration, thereby can exhibit facial expressions, helpful for better communication. CNAF effectively captured particulate matter (PM) by mechanical and electrostatic filtration mechanisms. The temperature of CNAF could be controlled by Joule-heating up to 100 °C with thermal stability. CNAF successfully inhibited the growth of E. coli because of the oligodynamic effect of copper. With heat sterilization, the antibacterial efficiency against G. anodireducens was greatly improved up to 99.3% within 10 min. CNAF showed high reusability with stable filtration efficiency and thermal antibacterial efficacy after five repeated uses. Our result suggests an alternative form of active antimicrobial air filter in preparation for the current and future pandemic situations.


Assuntos
Filtros de Ar , COVID-19 , Escherichia coli , Filtração , Humanos , SARS-CoV-2 , Esterilização
7.
Sensors (Basel) ; 22(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36015787

RESUMO

As low-temperature plasma plays an important role in semiconductor manufacturing, plasma diagnostics have been widely employed to understand changes in plasma according to external control parameters, which has led to the achievement of appropriate plasma conditions normally termed the process window. During plasma etching, shifts in the plasma conditions both within and outside the process window can be observed; in this work, we utilized various plasma diagnostic tools to investigate the causes of these shifts. Cutoff and emissive probes were used to measure the electron density and plasma potential as indicators of the ion density and energy, respectively, that represent the ion energy flux. Quadrupole mass spectrometry was also used to show real-time changes in plasma chemistry during the etching process, which were in good agreement with the etching trend monitored via in situ ellipsometry. The results show that an increase in the ion energy flux and a decrease in the fluorocarbon radical flux alongside an increase in the input power result in the breaking of the process window, findings that are supported by the reported SiO2 etch model. By extending the SiO2 etch model with rigorous diagnostic measurements (or numerous diagnostic methods), more intricate plasma processing conditions can be characterized, which will be beneficial in applications and industries where different input powers and gas flows can make notable differences to the results.


Assuntos
Semicondutores , Dióxido de Silício , Temperatura Baixa , Temperatura
8.
Sensors (Basel) ; 22(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35162035

RESUMO

Although the recently developed cutoff probe is a promising tool to precisely infer plasma electron density by measuring the cutoff frequency (fcutoff) in the S21 spectrum, it is currently only applicable to low-pressure plasma diagnostics below several torr. To improve the cutoff probe, this paper proposes a novel method to measure the crossing frequency (fcross), which is applicable to high-pressure plasma diagnostics where the conventional fcutoff method does not operate. Here, fcross is the frequency where the S21 spectra in vacuum and plasma conditions cross each other. This paper demonstrates the fcross method through three-dimensional electromagnetic wave simulation as well as experiments in a capacitively coupled plasma source. Results demonstrate that the method operates well at high pressure (several tens of torr) as well as low pressure. In addition, through circuit model analysis, a method to estimate electron density from fcross is discussed. It is believed that the proposed method expands the operating range of the cutoff probe and thus contributes to its further development.

9.
Sensors (Basel) ; 22(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36016029

RESUMO

As the importance of ion-assisted surface processing based on low-temperature plasma increases, the monitoring of ion energy impinging into wafer surfaces becomes important. Monitoring methods that are noninvasive, real-time, and comprise ion collision in the sheath have received much research attention. However, in spite of this fact, most research was performed in invasive, not real-time, and collisionless ion sheath conditions. In this paper, we develop a noninvasive real-time IED monitoring system based on an ion trajectory simulation where the Monte Carlo collision method and an electrical model are adopted to describe collisions in sheaths. We technically, theoretically, and experimentally investigate the IED measurement with the proposed method, and compared it with the result of IEDs measured via a quadrupole mass spectrometer under various conditions. The comparison results show that there was no major change in the IEDs as radio-frequency power increased or the IED gradually became broad as gas pressure increased, which was in a good agreement with the results of the mass spectrometer.

10.
Sensors (Basel) ; 22(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36081045

RESUMO

As the analysis of complicated reaction chemistry in bulk plasma has become more important, especially in plasma processing, quantifying radical density is now in focus. For this work, appearance potential mass spectrometry (APMS) is widely used; however, the original APMS can produce large errors depending on the fitting process, as the fitting range is not exactly defined. In this research, to reduce errors resulting from the fitting process of the original method, a new APMS approach that eliminates the fitting process is suggested. Comparing the neutral densities in He plasma between the conventional method and the new method, along with the real neutral density obtained using the ideal gas equation, confirmed that the proposed quantification approach can provide more accurate results. This research will contribute to improving the precision of plasma diagnosis and help elucidate the plasma etching process.


Assuntos
Plasma , Humanos , Masculino , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes
11.
Sensors (Basel) ; 22(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897990

RESUMO

As the importance of measuring electron density has become more significant in the material fabrication industry, various related plasma monitoring tools have been introduced. In this paper, the development of a microwave probe, called the measurement of lateral electron density (MOLE) probe, is reported. The basic properties of the MOLE probe are analyzed via three-dimensional electromagnetic wave simulation, with simulation results showing that the probe estimates electron density by measuring the surface wave resonance frequency from the reflection microwave frequency spectrum (S11). Furthermore, an experimental demonstration on a chamber wall measuring lateral electron density is conducted by comparing the developed probe with the cutoff probe, a precise electron density measurement tool. Based on both simulation and experiment results, the MOLE probe is shown to be a useful instrument to monitor lateral electron density.


Assuntos
Elétrons , Micro-Ondas , Simulação por Computador , Monitorização Fisiológica , Vibração
12.
Sensors (Basel) ; 22(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35957427

RESUMO

As the conventional voltage and current (VI) probes widely used in plasma diagnostics have separate voltage and current sensors, crosstalk between the sensors leads to degradation of measurement linearity, which is related to practical accuracy. Here, we propose a VI probe with a floating toroidal coil that plays both roles of a voltage and current sensor and is thus free from crosstalk. The operation principle and optimization conditions of the VI probe are demonstrated and established via three-dimensional electromagnetic wave simulation. Based on the optimization results, the proposed VI probe is fabricated and calibrated for the root-mean-square (RMS) voltage and current with a high-voltage probe and a vector network analyzer. Then, it is evaluated through a comparison with a commercial VI probe, with the results demonstrating that the fabricated VI probe achieved a slightly higher linearity than the commercial probe: R2 of 0.9967 and 0.9938 for RMS voltage and current, respectively. The proposed VI probe is believed to be applicable to plasma diagnostics as well as process monitoring with higher accuracy.

13.
Biochem Biophys Res Commun ; 552: 44-51, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33743348

RESUMO

Hepatocellular carcinoma (HCC) is the fifth common types of cancer with poor prognosis in the world. Honokiol (HNK), a natural biphenyl compound derived from the magnolia plant, has been reported to exert anticancer effects, but its mechanism has not been elucidated exactly. In the present study, HNK treatment significantly suppressed the migration ability of HepG2 and Hep3B human hepatocellular carcinoma. The treatment reduced the expression levels of the genes associated with cell migration, such as S100A4, MMP-2, MMP-9 and Vimentin. Interestingly, treatment with HNK significantly reduced the expression level of Cyclophilin B (CypB) which stimulates cancer cell migration. However, overexpressed CypB abolished HNK-mediated suppression of cell migration, and reversed the apoptotic effects of HNK. Altogether, we concluded that the suppression of migration activities by HNK was through down-regulated CypB in HCC. These finding suggest that HNK may be a promising candidate for HCC treatment via regulation of CypB.


Assuntos
Compostos de Bifenilo/farmacologia , Carcinoma Hepatocelular/genética , Movimento Celular/efeitos dos fármacos , Ciclofilinas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Lignanas/farmacologia , Neoplasias Hepáticas/genética , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ciclofilinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
14.
EMBO Rep ; 20(2)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30622216

RESUMO

Saponins function as a natural self-defense mechanism for plants to deter various insects due to their unpleasant taste and their toxicity. Here, we provide evidence that saponin from Quillaja saponaria functions as an antifeedant as well as an insecticide to ward off insects in both the larval and the adult stages. Using a behavioral screen of 26 mutant fly lines, we show that the Gr28b gene cluster plays a role in saponin avoidance in the labellum. The Gr28b mutant does not avoid saponin and exhibits increased lethality when fed saponin-mixed food. Tissue-specific rescue experiments with five different Gr28b isoforms revealed that only the Gr28b.c isoform is required for saponin sensation. We propose that in contrast to sensing many other bitter compounds, saponin sensing does not require the function of core taste receptors, such as GR32a, GR33a, and GR66a. Our results reveal a novel role for GR28b in taste. In addition, the ability of saponin to act as insecticides as well as antifeedants suggests its potential application in controlling insect pests.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Receptores de Superfície Celular/metabolismo , Saponinas/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster/efeitos dos fármacos , Inseticidas/farmacologia , Ligação Proteica , Receptores de Superfície Celular/genética
15.
Am J Dermatopathol ; 43(5): 356-361, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33055535

RESUMO

ABSTRACT: Actinic keratosis (AK) and Bowen's disease (BD) are common premalignant lesions of invasive squamous cell carcinoma that have different pathogenesis and clinical significance. Fatty acid-binding protein 5 (FABP5) is responsible for keratinocyte homeostasis and differentiation; however, no study has revealed its expression in AK and BD. Our study aimed to investigate the differential expression and significance of FABP5 in these lesions. Patients with pathologically confirmed cases of AK (n = 37) and BD (n = 12) were included in this study. FABP5 immunostaining pattern was assessed in the normal skin, AK and BD lesions, with a focus on the staining patterns of basal cells, atypical keratinocytes, and uninvolved epidermal keratinocytes. All patients with AK showed negative FABP5 expression in the atypical cells in the basal layer, whereas the uninvolved upper layers showed diffuse, strong FABP5 expression, regardless of the grade of AK. All patients with BD showed heterogeneous and diffuse FABP5 expression in atypical cells of all layers of the epidermis. This study is the first to investigate the role of FABP5 in premalignant skin lesions. The unique immunohistochemical localization of the FABP5 can be a helpful diagnostic marker, and altered fatty acid metabolism may be the key in understanding the different pathophysiology of AK and BD.


Assuntos
Doença de Bowen/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Ceratose Actínica/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Doença de Bowen/diagnóstico , Doença de Bowen/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Ceratose Actínica/diagnóstico , Ceratose Actínica/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
16.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204438

RESUMO

Hepatitis C virus (HCV) is associated with various liver diseases. Chronic HCV infection is characterized by an abnormal host immune response. Therefore, it is speculated that to suppress HCV, a well-regulated host immune response is necessary. 2-O-methylhonokiol was identified by the screening of anti-HCV compounds using Renilla luciferase assay in Huh 7.5/Con 1 genotype 1b replicon cells. Here, we investigated the mechanism by which 2-O-methylhonokiol treatment inhibits HCV replication using real-time PCR. Our data shows that treatment with 2-O-methylhonokiol activated innate immune responses via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) pathway. Additionally, the immunoprecipitation result shows that treatment with 2-O-methylhonokiol augmented tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) by preventing p62 from binding to TRAF6, resulting in reduced autophagy caused by HCV. Finally, we reproduced our data with the conditioned media from 2-O-methylhonokiol-treated cells. These findings strongly suggest that 2-O-methylhonokiol enhances the host immune response and suppresses HCV replication via TRAF6-mediated NF-kB activation.


Assuntos
Hepacivirus/fisiologia , Hepatite C/metabolismo , Hepatite C/virologia , Interações Hospedeiro-Patógeno , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Replicação Viral , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Células Cultivadas , Hepatite C/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Modelos Biológicos , Estrutura Molecular
17.
Wound Repair Regen ; 28(2): 202-210, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31688987

RESUMO

The aim of this study was to determine novel candidate genes for Dupuytren's disease by performing a meta-analysis. We identified 261 genes (111 up-regulated and 150 down-regulated) that were consistently expressed differentially in Dupuytren's disease across the studies. We performed functional enrichment on total sets of the identified 261 genes and confirmed that most of the genes were closely related to common processes of diseases in general. From the integrated studies of the gene-correlation network and the protein-protein interaction network, we identified three functional modules in the gene co-expression network and four hub gene clusters in the protein-protein interaction network that shared the same genes and represented similar biological functions, implying that the seven groups identified in the systematic analysis of these two networks might be involved in the pathogenesis of Dupuytren's disease. This work demonstrates potential in developing experimental and clinical strategies for understanding and treating Dupuytren's disease.


Assuntos
Contratura de Dupuytren/genética , Transcriptoma , Linhagem Celular , Bases de Dados Genéticas , Regulação para Baixo , Contratura de Dupuytren/diagnóstico , Contratura de Dupuytren/terapia , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , Terapia de Alvo Molecular , Mapas de Interação de Proteínas , Fatores de Transcrição/genética , Regulação para Cima
18.
Sensors (Basel) ; 20(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198214

RESUMO

In this paper, a novel beamforming technique is proposed as the over-the-air computation (AirComp) framework in a multiple-input multiple-output (MIMO) Internet-of-things (IoT) network consisting of multiple IoT sensors (STAs) and a single access point (AP). We assume that each IoT device has the channel state information (CSI) from itself to the AP and the AP has the global CSI of all IoT devices. We consider the mean squared error (MSE), which represents the reliability of function computation, as a performance metric. In short, each IoT device exploits maximum-ratio transmission (MRT) as a transmit beamforming technique to improve MSE performance by taking full advantage of multiple transmit antennae. Moreover, for the receive beamforming, we first consider a receive antenna selection (RAS) technique as the simplest beamforming method at the AP. Then, a semi-definite relaxation (SDR) method and a successive convex approximation (SCA) algorithm are considered and compared with each other in terms of MSE. Finally, we propose a novel two-step beamforming algorithm to further improve the MSE performance of the aforementioned techniques. We have numerically verified through computer simulations that the proposed framework has an improved MSE performance of about 6dB compared to the conventional single-input multiple-output (SIMO) AirComp, even with only two transmit antennae, and the modified MRT outperforms the other transmit beamforming techniques. Furthermore, the proposed receive beamforming technique, a two-step algorithm, shows the best performance in terms of MSE compared to prior studies.

19.
Int J Mol Sci ; 21(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322579

RESUMO

Osteoporosis is a complex multifactorial condition of the musculoskeletal system. Osteoporosis and osteoporotic vertebral fracture (OVF) are associated with high medical costs and can lead to poor quality of life. Genetic factors are important in determining bone mass and structure, as well as any predisposition for bone degradation and OVF. However, genetic factors are not enough to explain osteoporosis development and OVF occurrence. Epigenetics describes a mechanism for controlling gene expression and cellular processes without altering DNA sequences. The main mechanisms in epigenetics are DNA methylation, histone modifications, and non-coding RNAs (ncRNAs). Recently, alterations in epigenetic mechanisms and their activity have been associated with osteoporosis and OVF. Here, we review emerging evidence that epigenetics contributes to the machinery that can alter DNA structure, gene expression, and cellular differentiation during physiological and pathological bone remodeling. A progressive understanding of normal bone metabolism and the role of epigenetic mechanisms in multifactorial osteopathy can help us better understand the etiology of the disease and convert this information into clinical practice. A deep understanding of these mechanisms will help in properly coordinating future individual treatments of osteoporosis and OVF.


Assuntos
Epigenômica/métodos , Fraturas Ósseas/genética , Osteoporose/genética , Fraturas por Osteoporose/genética , Metilação de DNA/genética , Metilação de DNA/fisiologia , Epigênese Genética/genética , Epigênese Genética/fisiologia , Fraturas Ósseas/patologia , Humanos , Fraturas da Coluna Vertebral/genética
20.
Int J Mol Sci ; 21(15)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752233

RESUMO

Hepatic hepcidin is a well-known major iron regulator and has been reported to be closely related to hepatitis C virus (HCV) replication. However, pharmacological targeting of the hepcidin in HCV replication has not been reported. A short-chain fatty acid, 4-Phenyl butyrate (4-PBA), is an acid chemical chaperone that acts as a histone deacetylase inhibitor (HDACi) to promote chromosomal histone acetylation. Here, we investigated the therapeutic effect of 4-PBA on hepcidin expression and HCV replication. We used HCV genotype 1b Huh 7.5-Con1 replicon cells and engraftment of NOD/SCID mice as in vitro and in vivo models to test the effect of 4-PBA. It was found that 4-PBA inhibited HCV replication in Huh7.5-Con1 replicon cells in a concentration- and time-dependent manner through the induction of hepcidin expression by epigenetic modification and subsequent upregulation of interferon-α signaling. HCV formed a membranous web composed of double-membrane vesicles and was utilized for RNA replication. Moreover, 4-PBA also disrupted the integrity of the membranous web and interfered with the molecular interactions critical for the assembly of the HCV replication complex. These findings suggest that 4-PBA is a key epigenetic inducer of anti-HCV hepatic hepcidin and might at least in part play a role in targeting host factors related to HCV infection as an attractive complement to current HCV therapies.


Assuntos
Epigênese Genética/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Hepcidinas/genética , Fenilbutiratos/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Expressão Gênica/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/fisiologia , Hepatite C/prevenção & controle , Hepatite C/virologia , Hepcidinas/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos NOD , Camundongos SCID , Estrutura Molecular , Fenilbutiratos/química , Bibliotecas de Moléculas Pequenas/química , Replicação Viral/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA