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1.
ACS Nano ; 18(41): 28292-28300, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39364669

RESUMO

Selectors are critical components for reducing the sneak path leakage currents in emerging resistive random-access memory (RRAM) arrays. Two-dimensional (2D) materials provide a rich choice of materials with van der Waals stacking to form the heterostructure selectors with controllable energy barriers. Here, we experimentally demonstrate 2D-material-based heterostructure selectors with exponential current-voltage (I-V) relationships and integrate them with hafnium oxide (HfOx)-based RRAMs, forming one-selector-one-resistor (1S1R) cells. The multilayer graphene (MG)/tungsten disulfide (WS2)/platinum (Pt) selector contains two asymmetric heterojunctions with different Schottky barriers, which lead to highly nonlinear and asymmetric I-V characteristics. The 2D selectors in 1S1R cells can successfully drive RRAMs, reduce sneak path leakage current by more than 100 times, and provide the set compliance current. The 1S1R cells are further modeled and integrated into both planar and 3D memory arrays, with circuit-level simulations demonstrating that the presence of 2D selectors in large memory arrays can reduce the power consumption by up to 86%, improve the read/write margin by up to 31%, and avoid write failure. Such a platform holds high potential for constructing 3D high-density memories and performing in-memory computing.

2.
RSC Adv ; 14(43): 31723-31729, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39376526

RESUMO

Oxidative chemical vapor deposition (oCVD) has emerged as one of the most promising techniques for conjugated polymer deposition, especially for unsubstituted polythiophene thin films. oCVD overcomes the insolubility challenge that unsubstituted polythiophene (PT) presents and adds the ability to control morphological and molecular structure. This control is important for enhancing the performance of devices which incorporate organic conductors. In this work, Raman spectroscopy, UV-vis spectroscopy, and AFM reveal that the relative amount of distortion in the polymer chains, the conjugation length and the film roughness are all affected by the CVD deposition conditions, in particular the reactor pressure. PT films deposited at 150 mT and 300 mT are found to have lower chain distortion, longer conjugation lengths and lower surface roughness compared to other deposition pressures. The oCVD PT film is also directly grafted to the trichloro(phenylethyl)silane (PTS) treated substrates, where the effect of PTS grafting is observed to significantly affect film roughness. In addition, we report the first study of the effect of oCVD PT films on the performance of lithium-ion battery electrodes. These oCVD PT films are used to engineer a LiCoO2 cathode in lithium-ion batteries. The observed improvements are a 52% increase in the discharge capacity (67 mA h g-1 to 102 mA h g-1) at 10C and a 500% improvement in cycling stability tested at 5C within the voltage range of 3.0-4.5 V (capacity fading rate is reduced from 1.92%/cycle to 0.32%/cycle).

3.
Medicine (Baltimore) ; 103(42): e39744, 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39432591

RESUMO

One person suffers from dementia every 3 seconds globally. Thirteen older adults aged 65 and older will have dementia, and 1 in 5 older adults over the age of 80 years will have dementia in Taiwan. Older adults should be equipped with demonstrated health beliefs regarding dementia prevention and health promotion about Ascertain Dementia 8-item Questionnaire (AD8), cues to action, health beliefs, self-efficacy, and behavioral intention in daily life. The purpose of this study was to survey older adults' demographic background, AD8, cues to action, health beliefs, self-efficacy, and behavioral intention for dementia prevention and health promotion. A cross-sectional survey design was used. Convenience sampling was performed. A total of 330 older adults participated in the study. The questionnaire used in this study included questions on older adults' demographic background, AD8, cues to action, health beliefs, self-efficacy, and behavioral intention. The researcher collected complete data by receiving the sampling on paper or by interview from October 8, 2021, to February 12, 2022. The SPSS 23.0 statistical package was employed for quantitative analysis. Data analysis included frequency, percentage, mean, standard deviation (SD), Spearman's rho correlation, and simple regression analysis. The findings showed that older adults had the following mean scores on health beliefs (perceived susceptibility 13.45 ± SD 2.34, perceived severity 13.54 ± SD 2.69, perceived benefits 16.57 ± SD 2.84, perceived barriers 8.20 ± SD 3.69), self-efficacy 16.96 ± SD3.52, and behavioral intention 19.56 ± SD 3.51. Older adults' demographic background, perceived susceptibility, perceived severity, perceived benefits, perceived barriers, and self-efficacy explained 56.1% of the variance in behavioral intention. The conclusions of the study indicated that older adults' demographic background, AD8, cues to action, health beliefs, self-efficacy, and behavioral intention constituted the main factors for effective dementia prevention and health promotion. In the future, the research team will continue to explore older adults' dementia prevention and develop many strategies on health promotion, as well as slowing the aging brain process.


Assuntos
Demência , Promoção da Saúde , Autoeficácia , Humanos , Estudos Transversais , Taiwan , Masculino , Feminino , Idoso , Demência/prevenção & controle , Demência/psicologia , Promoção da Saúde/métodos , Idoso de 80 Anos ou mais , Modelo de Crenças de Saúde , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
4.
Commun Biol ; 7(1): 1197, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342051

RESUMO

Superparamagnetic iron oxide nanoparticles (SPIONs) are characterized by their exceptional susceptibility and relaxivity at ultra-low field (ULF) regimes, make them a promising contrast agent (CA) for ULF MRI. Despite their distinct advantages, the translation of these properties into clinically valuable image contrast in ULF MRI remains underexplored. In this study, we investigate the use of SPIONs to generate in vivo MRI contrast at 6.5 mT within the organs and vascular system of rodents. This investigation includes comprehensive SPION characterization and phantom imaging experiments to validate the utility of SPIONs to produce positive image contrast and to facilitate phase-sensitive imaging at ULF. Optimized balanced steady-state free precession (bSSFP) and spoiled gradient echo (SPGR) MRI sequences are used to generate in vivo contrast by leveraging the distinctive properties of SPIONs at ULF. Imaging studies in rodents reveal positive organ contrast attainable in magnitude images, and MRI phase maps can be used to visualize the vascular system. This work demonstrates the effectiveness of SPIONs in enhancing preclinical organ and vascular imaging at ULF; it bridges the gap between the study of the distinctive physical properties of SPIONs and the demonstration of in vivo image contrast.


Assuntos
Meios de Contraste , Nanopartículas Magnéticas de Óxido de Ferro , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Animais , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Ratos , Camundongos , Masculino , Ratos Sprague-Dawley
5.
PLoS Pathog ; 20(9): e1012485, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39259704

RESUMO

Hepatitis B virus (HBV) exploits the endosomal sorting complexes required for transport (ESCRT)/multivesicular body (MVB) pathway for virion budding. In addition to enveloped virions, HBV-replicating cells nonlytically release non-enveloped (naked) capsids independent of the integral ESCRT machinery, but the exact secretory mechanism remains elusive. Here, we provide more detailed information about the existence and characteristics of naked capsid, as well as the viral and host regulations of naked capsid egress. HBV capsid/core protein has two highly conserved Lysine residues (K7/K96) that potentially undergo various types of posttranslational modifications for subsequent biological events. Mutagenesis study revealed that the K96 residue is critical for naked capsid egress, and the intracellular egress-competent capsids are associated with ubiquitinated host proteins. Consistent with a previous report, the ESCRT-III-binding protein Alix and its Bro1 domain are required for naked capsid secretion through binding to intracellular capsid, and we further found that the ubiquitinated Alix binds to wild type capsid but not K96R mutant. Moreover, screening of NEDD4 E3 ubiquitin ligase family members revealed that AIP4 stimulates the release of naked capsid, which relies on AIP4 protein integrity and E3 ligase activity. We further demonstrated that AIP4 interacts with Alix and promotes its ubiquitination, and AIP4 is essential for Alix-mediated naked capsid secretion. However, the Bro1 domain of Alix is non-ubiquitinated, indicating that Alix ubiquitination is not absolutely required for AIP4-induced naked capsid secretion. Taken together, our study sheds new light on the mechanism of HBV naked capsid egress in viral life cycle.


Assuntos
Capsídeo , Vírus da Hepatite B , Ubiquitina-Proteína Ligases Nedd4 , Ubiquitina-Proteína Ligases , Liberação de Vírus , Humanos , Proteínas de Ligação ao Cálcio , Capsídeo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Hepatite B/metabolismo , Hepatite B/virologia , Vírus da Hepatite B/metabolismo , Vírus da Hepatite B/fisiologia , Vírus da Hepatite B/genética , Ubiquitina-Proteína Ligases Nedd4/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Liberação de Vírus/fisiologia
6.
Ecol Evol ; 14(8): e70175, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39170054

RESUMO

Investigating fundamental processes in biology requires the ability to ground broad questions in species-specific natural history. This is particularly true in the study of behavior because an organism's experience of the environment will influence the expression of behavior and the opportunity for selection. Here, we provide a review of the natural history and behavior of burying beetles of the genus Nicrophorus to provide the groundwork for comparative work that showcases their remarkable behavioral and ecological diversity. Burying beetles have long fascinated scientists because of their well-developed parenting behavior, exhibiting extended post-hatching care of offspring that varies extensively within and across taxa. Despite the burgeoning success of burying beetles as a model system for the study of behavioral evolution, there has not been a review of their behavior, ecology, and evolution in over 25 years. To address this gap, we leverage a developing community of researchers who have contributed to a detailed knowledge of burying beetles to highlight the utility of Nicrophorus for investigating the causes and consequences of social and behavioral evolution.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39181427

RESUMO

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) risk prediction models established in patients with chronic hepatitis B receiving a nucleos(t)ide analogue (NA) rarely include viral factors because of mediocre predictability of traditional viral markers. Here, we investigate the role of serum hepatitis B virus (HBV) RNA, a novel biomarker, in predicting HCC risk in NA-treated patients. METHODS: A total of 1374 NA-treated patients were enrolled from 2 prospective chronic hepatitis B cohorts. Serum HBV RNA was detected at baseline, year 1, 2 and 3 of treatment. Cox proportional-hazard model was used to investigate the association of HBV RNA kinetics with HCC risk. RESULTS: After a median follow-up of 5.4 years, 76 patients developed HCC. HBV RNA declines at year 1 (adjusted hazard ratio, 0.70, P = .009) and 2 (adjusted hazard ratio, 0.71; P = .016) were independently associated with HCC risk. Patients with less HBV RNA decline at year 1 (≤0.4 log10 copies/mL) or 2 (≤0.6 log10 copies/mL) had 2.22- and 2.09-folds higher HCC risk, respectively, than those with more declines. When incorporating these early on-treatment HBV RNA declines into existing HCC risk scores, including PAGE-B (age, sex, and platelets), modified PAGE-B (mPAGE-B) (age, sex, platelets, and albumin), and aMAP (age, sex, platelets, and albumin-bilirubin score) score, they could enhance their predictive performance (ie, C-index 0.814 vs 0.78 [model (PAGE-B + year-1 HBV RNA decline) vs PAGE-B score based on baseline parameters]). CONCLUSIONS: Serum HBV RNA declines at year 1 and 2 were significantly associated with on-treatment HCC risk. Incorporating early on-treatment HBV RNA declines into HCC risk prediction models can be useful tools to guide appropriate surveillance strategies in NA-treated patients.

8.
Methods Mol Biol ; 2837: 159-170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044083

RESUMO

In recent years, serum hepatitis B virus (HBV) RNA has been identified as a promising noninvasive surrogate biomarker of intrahepatic covalently closed circular DNA (cccDNA), detection of which requires an invasive liver biopsy in patients with chronic HBV infection. It is impractical to detect intrahepatic cccDNA as a routine diagnosis for chronic hepatitis B (CHB) patients in clinical management. Here, we describe a detailed protocol for serum HBV RNA quantification, which can reflect the activity of intrahepatic cccDNA. The procedure includes three major steps: (1) Simultaneous isolation of HBV DNA and RNA from patients' serum, (2) DNase I digestion for removing HBV DNA contamination, and (3) HBV RNA quantification by one-step reverse transcription qPCR.


Assuntos
Vírus da Hepatite B , RNA Viral , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , RNA Viral/sangue , RNA Viral/genética , RNA Viral/isolamento & purificação , DNA Viral/sangue , DNA Viral/genética , Hepatite B Crônica/virologia , Hepatite B Crônica/sangue , Hepatite B Crônica/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , DNA Circular/sangue , DNA Circular/isolamento & purificação , DNA Circular/genética , Carga Viral/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos
9.
Sci Rep ; 14(1): 16455, 2024 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014184

RESUMO

Diffusion Kurtosis Imaging (DKI)-derived metrics are recognized as indicators of maturation in neonates with low-grade germinal matrix and intraventricular hemorrhage (GMH-IVH). However, it is not yet known if these factors are associated with neurodevelopmental outcomes. The objective of this study was to acquire DKI-derived metrics in neonates with low-grade GMH-IVH, and to demonstrate their association with later neurodevelopmental outcomes. In this prospective study, neonates with low-grade GMH-IVH and control neonates were recruited, and DKI were performed between January 2020 and March 2021. These neonates underwent the Bayley Scales of Infant Development test at 18 months of age. Mean kurtosis (MK), radial kurtosis (RK) and gray matter values were measured. Spearman correlation analyses were conducted for the measured values and neurodevelopmental outcome scores. Forty controls (18 males, average gestational age (GA) 30 weeks ± 1.3, corrected GA at MRI scan 38 weeks ± 1) and thirty neonates with low-grade GMH-IVH (13 males, average GA 30 weeks ± 1.5, corrected GA at MRI scan 38 weeks ± 1). Neonates with low-grade GMH-IVH exhibited lower MK and RK values in the PLIC and the thalamus (P < 0.05). The MK value in the thalamus was associated with Mental Development Index (MDI) (r = 0.810, 95% CI 0.695-0.13; P < 0.001) and Psychomotor Development Index (PDI) (r = 0.852, 95% CI 0.722-0.912; P < 0.001) scores. RK value in the caudate nucleus significantly and positively correlated with MDI (r = 0.496, 95% CI 0.657-0.933; P < 0.001) and PDI (r = 0.545, 95% CI 0.712-0.942; P < 0.001) scores. The area under the curve (AUC) were used to assess diagnostic performance of MK and RK in thalamus (AUC = 0.866, 0.787) and caudate nucleus (AUC = 0.833, 0.671) for predicting neurodevelopmental outcomes. As quantitative neuroimaging markers, MK in thalamus and RK in caudate nucleus may help predict neurodevelopmental outcomes in neonates with low-grade GMH-IVH.


Assuntos
Imagem de Tensor de Difusão , Humanos , Masculino , Recém-Nascido , Feminino , Imagem de Tensor de Difusão/métodos , Estudos Prospectivos , Hemorragia Cerebral/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/etiologia , Lactente , Hemorragia Cerebral Intraventricular/diagnóstico por imagem , Idade Gestacional , Desenvolvimento Infantil , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia
10.
Viruses ; 16(6)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38932182

RESUMO

Tripartite motif (TRIM) proteins, comprising a family of over 100 members with conserved motifs, exhibit diverse biological functions. Several TRIM proteins influence viral infections through direct antiviral mechanisms or by regulating host antiviral innate immune responses. To identify TRIM proteins modulating hepatitis B virus (HBV) replication, we assessed 45 human TRIMs in HBV-transfected HepG2 cells. Our study revealed that ectopic expression of 12 TRIM proteins significantly reduced HBV RNA and subsequent capsid-associated DNA levels. Notably, TRIM65 uniquely downregulated viral pregenomic (pg) RNA in an HBV-promoter-specific manner, suggesting a targeted antiviral effect. Mechanistically, TRIM65 inhibited HBV replication primarily at the transcriptional level via its E3 ubiquitin ligase activity and intact B-box domain. Though HNF4α emerged as a potential TRIM65 substrate, disrupting its binding site on the HBV genome did not completely abolish TRIM65's antiviral effect. In addition, neither HBx expression nor cellular MAVS signaling was essential to TRIM65-mediated regulation of HBV transcription. Furthermore, CRISPR-mediated knock-out of TRIM65 in the HepG2-NTCP cells boosted HBV infection, validating its endogenous role. These findings underscore TRIM proteins' capacity to inhibit HBV transcription and highlight TRIM65's pivotal role in this process.


Assuntos
Vírus da Hepatite B , Transcrição Gênica , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Replicação Viral , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Células Hep G2 , Proteínas com Motivo Tripartido/metabolismo , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Hepatite B/virologia , Hepatite B/genética , Hepatite B/imunologia , Regiões Promotoras Genéticas , RNA Viral/genética , RNA Viral/metabolismo
11.
Molecules ; 29(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38792214

RESUMO

BACKGROUND: Staphylococcus aureus is a common pathogenic microorganism in humans and animals. Type II NADH oxidoreductase (NDH-2) is the only NADH:quinone oxidoreductase present in this organism and represents a promising target for the development of anti-staphylococcal drugs. Recently, myricetin, a natural flavonoid from vegetables and fruits, was found to be a potential inhibitor of NDH-2 of S. aureus. The objective of this study was to evaluate the inhibitory properties of myricetin against NDH-2 and its impact on the growth and expression of virulence factors in S. aureus. RESULTS: A screening method was established to identify effective inhibitors of NDH-2, based on heterologously expressed S. aureus NDH-2. Myricetin was found to be an effective inhibitor of NDH-2 with a half maximal inhibitory concentration (IC50) of 2 µM. In silico predictions and enzyme inhibition kinetics further characterized myricetin as a competitive inhibitor of NDH-2 with respect to the substrate menadione (MK). The minimum inhibitory concentrations (MICs) of myricetin against S. aureus strains ranged from 64 to 128 µg/mL. Time-kill assays showed that myricetin was a bactericidal agent against S. aureus. In line with being a competitive inhibitor of the NDH-2 substrate MK, the anti-staphylococcal activity of myricetin was antagonized by MK-4. In addition, myricetin was found to inhibit the gene expression of enterotoxin SeA and reduce the hemolytic activity induced by S. aureus culture on rabbit erythrocytes in a dose-dependent manner. CONCLUSIONS: Myricetin was newly discovered to be a competitive inhibitor of S. aureus NDH-2 in relation to the substrate MK. This discovery offers a fresh perspective on the anti-staphylococcal activity of myricetin.


Assuntos
Flavonoides , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Flavonoides/farmacologia , Flavonoides/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/enzimologia , Antibacterianos/farmacologia , Antibacterianos/química , NADH Desidrogenase/antagonistas & inibidores , NADH Desidrogenase/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Animais , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Humanos , Fatores de Virulência/antagonistas & inibidores , Fatores de Virulência/metabolismo
12.
iScience ; 27(5): 109659, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38706841

RESUMO

Abnormal mTORC1 activation by the lysosomal Ragulator complex has been implicated in cancer and glycolytic metabolism associated with drug resistance. Fasting upregulates RNF152 and mediates the metabolic status of cells. We report that RNF152 regulates mTORC1 signaling by targeting a Ragulator subunit, p18, and attenuates gemcitabine resistance in gallbladder cancer (GBC). We detected levels of RNF152 and p18 in tissues and undertook mechanistic studies using activators, inhibitors, and lentivirus transfections. RNF152 levels were significantly lower in GBC than in adjacent non-cancer tissues. Fasting impairs glycolysis, induces gemcitabine sensitivity, and upregulates RNF152 expression. RNF152 overexpression increases the sensitivity of GBC cells to gemcitabine, whereas silencing RNF152 has the opposite effect. Fasting-induced RNF152 ubiquitinates p18, resulting in proteasomal degradation. RNF152 deficiency increases the lysosomal localization of p18 and increases mTORC1 activity, to promote glycolysis and decrease gemcitabine sensitivity. RNF152 suppresses mTORC1 activity to inhibit glycolysis and enhance gemcitabine sensitivity in GBC.

13.
Acta Biomater ; 180: 183-196, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38604465

RESUMO

The utilization of biodegradable magnesium (Mg) alloys in the fabrication of temporary non-vascular stents is an innovative trend in biomedical engineering. However, the heterogeneous degradation profiles of these biomaterials, together with potential bacterial colonization that could precipitate infectious or stenotic complications, are critical obstacles precluding their widespread clinical application. In pursuit of overcoming these limitations, this study applies the principles of biomimicry, particularly the hydrophobic and anti-fouling characteristics of lotus leaves, to pioneer the creation of nanocomposite coatings. These coatings integrate poly-trimethylene carbonate (PTMC) with covalent organic frameworks (COFs), to modify the stent's surface property. The strategic design of the coating's topography, porosity, and self-polishing capabilities collectively aims to decelerate degradation processes and minimize biological adhesion. The protective qualities of the coatings were substantiated through rigorous testing in both in vitro dynamic bile tests and in vivo New Zealand rabbit choledochal models. Empirical findings from these trials confirmed that the implementation of COF-based nanocomposite coatings robustly fortifies Mg implantations, conferring heightened resistance to both biocorrosion and biofouling as well as improved biocompatibility within bodily environments. The outcomes of this research elucidate a comprehensive framework for the multifaceted strategies against stent corrosion and fouling, thereby charting a visionary pathway toward the systematic conception of a new class of reliable COF-derived surface modifications poised to amplify the efficacy of Mg-based stents. STATEMENT OF SIGNIFICANCE: Biodegradable magnesium (Mg) alloys are widely utilized in temporary stents, though their rapid degradation and susceptibility to bacterial infection pose significant challenges. Our research has developed a nanocomposite coating inspired by the lotus, integrating poly-trimethylene carbonate with covalent organic frameworks (COF). The coating achieved self-polishing property and optimal surface energy on the Mg substrate, which decelerates stent degradation and reduces biofilm formation. Comprehensive evaluations utilizing dynamic bile simulations and implantation in New Zealand rabbit choledochal models reveal that the coating improves the durability and longevity of the stent. The implications of these findings suggest the potential COF-based Mg alloy stent surface treatments and a leap forward in advancing stent performance and endurance in clinical applications.


Assuntos
Implantes Absorvíveis , Materiais Revestidos Biocompatíveis , Magnésio , Nanocompostos , Stents , Animais , Coelhos , Magnésio/química , Magnésio/farmacologia , Nanocompostos/química , Corrosão , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Incrustação Biológica/prevenção & controle , Dioxanos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Polímeros/química , Polímeros/farmacologia , Ligas/química , Ligas/farmacologia
14.
medRxiv ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38633799

RESUMO

Breast cancer screening is necessary to reduce mortality due to undetected breast cancer. Current methods have limitations, and as a result many women forego regular screening. Magnetic resonance imaging (MRI) can overcome most of these limitations, but access to conventional MRI is not widely available for routine annual screening. Here, we used an MRI scanner operating at ultra-low field (ULF) to image the left breasts of 11 women (mean age, 35 years ±13 years) in the prone position. Three breast radiologists reviewed the imaging and were able to discern the breast outline and distinguish fibroglandular tissue (FGT) from intramammary adipose tissue. Additionally, the expert readers agreed on their assessment of the breast tissue pattern including fatty, scattered FGT, heterogeneous FGT, and extreme FGT. This preliminary work demonstrates that ULF breast MRI is feasible and may be a potential option for comfortable, widely deployable, and low-cost breast cancer diagnosis and screening.

15.
Proc Natl Acad Sci U S A ; 121(14): e2312700121, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498725

RESUMO

In nature, leafhoppers cover their body surfaces with brochosomes as a protective coating. These leafhopper-produced brochosomes are hollow, buckyball-shaped, nanoscopic spheroids with through-holes distributed across their surfaces, representing a class of deployable optical materials that are rare in nature. Despite their discovery in the 1950s, it remains unknown why the sizes of brochosomes and their through-holes consistently fall within the range of hundreds of nanometers across different leafhopper species. Here, we demonstrate that the hierarchical geometries of brochosomes are engineered within a narrow size range with through-hole architecture to significantly reduce light reflection. By utilizing two-photon polymerization three-dimensional printing to fabricate high-fidelity synthetic brochosomes, we investigated the optical form-to-function relationship of brochosomes. Our results show that the diameters of brochosomes are engineered within a specific size range to maximize broadband light scattering, while the secondary through-holes are designed to function as short-wavelength, low-pass filters, further reducing light reflection. These synergistic effects enable brochosomes to achieve a substantial reduction in specular reflection, by up to approximately 80 to 94%, across a broadband wavelength range. Importantly, brochosomes represent a biological example demonstrating short-wavelength, low-pass filter functionality. Furthermore, our results indicate that the geometries of natural brochosomes may have evolved to effectively reduce reflection from ultraviolet to visible light, thereby enabling leafhoppers to evade predators whose vision spectrum encompasses both ultraviolet and visible light. Our findings offer key design insights into a class of deployable bioinspired optical materials with potential applications in omnidirectional antireflection coatings, optical encryption, and multispectral camouflage.

16.
Nature ; 629(8010): 114-120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38538797

RESUMO

Mountain ranges contain high concentrations of endemic species and are indispensable refugia for lowland species that are facing anthropogenic climate change1,2. Forecasting biodiversity redistribution hinges on assessing whether species can track shifting isotherms as the climate warms3,4. However, a global analysis of the velocities of isotherm shifts along elevation gradients is hindered by the scarcity of weather stations in mountainous regions5. Here we address this issue by mapping the lapse rate of temperature (LRT) across mountain regions globally, both by using satellite data (SLRT) and by using the laws of thermodynamics to account for water vapour6 (that is, the moist adiabatic lapse rate (MALRT)). By dividing the rate of surface warming from 1971 to 2020 by either the SLRT or the MALRT, we provide maps of vertical isotherm shift velocities. We identify 17 mountain regions with exceptionally high vertical isotherm shift velocities (greater than 11.67 m per year for the SLRT; greater than 8.25 m per year for the MALRT), predominantly in dry areas but also in wet regions with shallow lapse rates; for example, northern Sumatra, the Brazilian highlands and southern Africa. By linking these velocities to the velocities of species range shifts, we report instances of close tracking in mountains with lower climate velocities. However, many species lag behind, suggesting that range shift dynamics would persist even if we managed to curb climate-change trajectories. Our findings are key for devising global conservation strategies, particularly in the 17 high-velocity mountain regions that we have identified.


Assuntos
Altitude , Migração Animal , Biodiversidade , Mapeamento Geográfico , Aquecimento Global , Animais , África Austral , Brasil , Conservação dos Recursos Naturais , Aquecimento Global/estatística & dados numéricos , Umidade , Indonésia , Chuva , Refúgio de Vida Selvagem , Imagens de Satélites , Especificidade da Espécie , Temperatura , Fatores de Tempo
17.
Sci Adv ; 10(9): eadl4027, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38427742

RESUMO

Microscale thermal signature control using incoherent heat sources remains challenging, despite recent advancements in plasmonic materials and phase-change materials. Inspired by leafhopper-generated brochosomes, we design binary metastructures functioning as pixel twins to achieve pixelated thermal signature control at the microscale. In the infrared range, the pixel twins exhibit distinct emissivities, creating thermal counterparts of "0-1" binary states for storing and displaying information. In the visible range, the engineered surface morphology of the pixel twins ensures similar scattering behaviors. This renders them visually indistinguishable, thereby concealing the stored information. The brochosome-like pixel twins are self-emitting when thermally excited. Their structure-enabled functions do not rely on the permittivities of specific materials, which distinguishes them from the conventional laser-illuminated plasmonic holographic metasurfaces. The unique combination of visible camouflage and infrared display offers a systemic solution to microscale spatial control of thermal signatures and has substantial implications for optical security, anticounterfeiting, and data encryption.

18.
J Med Virol ; 96(2): e29400, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38293843

RESUMO

Serum hepatitis B virus (HBV) spliced RNAs (spRNAs) are ubiquitous in HBV-infected patients; however, their clinical significance remains unknown. Therefore, we aimed to explore the relationship between HBV spRNAs and liver disease progression in chronic hepatitis B (CHB) patients; in vitro cell line assessment was also performed. The serum HBV wild-type RNA (wtRNA) and spRNA levels were individually quantified in a cohort of 279 treatment-naïve, hepatitis B e antigen positive CHB patients with or without cirrhosis. The spRNA proportion was determined as (spRNA × 100%)/(spRNAs + wtRNA). 20 patients' serum samples underwent spRNA species profiling using next-generation sequencing. Serum spRNA species 1, 2, 3, 4, and 5 were the most common variants. The spRNA proportion varied from 0.00% to 19.02%, with higher levels in HBV genotype C patients than in those with genotype B (1.76% vs. 0.84%, p < 0.001). The spRNA proportion was positively associated with the alanine aminotransferase levels (r = 0.144, p = 0.053) and significantly higher in cirrhotic than in non-cirrhotic patients (1.69% vs. 1.04%, p = 0.001). Multivariate analysis revealed a 2.566-fold higher risk of cirrhosis in patients with elevated spRNA proportion (p = 0.024). In vitro experiments confirmed that spRNAs contributed to hepatic stellate cell activation, which is critical in liver fibrosis development. Therefore, increased HBV spRNA expression poses a risk for liver disease progression. Quantifying serum HBV spRNAs can aid in monitoring liver disease progression. Furthermore, the therapeutic targeting of spRNAs may improve the prognosis of patients with CHB.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , RNA/uso terapêutico , Cirrose Hepática/complicações , Antígenos E da Hepatite B , Progressão da Doença , DNA Viral/genética
19.
Nano Lett ; 24(5): 1502-1509, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277641

RESUMO

With the continuous advancement of nanotechnology, nanodevices have become crucial components in computing, sensing, and energy conversion applications. The structures of nanodevices typically possess subwavelength dimensions and separations, which pose significant challenges for understanding energy transport phenomena in nanodevices. Here, on the basis of a judiciously designed thermal photonic nanodevice, we report the first measurement of near-field energy transport between two coplanar subwavelength structures over temperature bias up to ∼190 K. Our experimental results demonstrate a 20-fold enhancement in energy transfer beyond blackbody radiation. In contrast with the well-established near-field interactions between two semi-infinite bodies, the subwavelength confinements in nanodevices lead to increased polariton scattering and reduction of supporting photonic modes and, therefore, a lower energy flow at a given separation. Our work unveils exciting opportunities for the rational design of nanodevices, particularly for coplanar near-field energy transport, with important implications for the development of efficient nanodevices for energy harvesting and thermal management.

20.
J Virol ; 97(10): e0076023, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37754759

RESUMO

IMPORTANCE: The biogenesis and clinical application of serum HBV pgRNA have been a research hotspot in recent years. This study further characterized the heterogeneity of the 3' terminus of capsid RNA by utilizing a variety of experimental systems conditionally supporting HBV genome replication and secretion, and reveal that the 3' truncation of capsid pgRNA is catalyzed by cellular ribonuclease(s) and viral RNaseH at positions after and before 3' DR1, respectively, indicating the 3' DR1 as a boundary between the encapsidated portion of pgRNA for reverse transcription and the 3' unprotected terminus, which is independent of pgRNA length and the 3' terminal sequence. Thus, our study provides new insights into the mechanism of pgRNA encapsidation and reverse transcription, as well as the optimization of serum HBV RNA diagnostics.


Assuntos
Capsídeo , Genoma Viral , Vírus da Hepatite B , RNA Viral , Replicação Viral , Capsídeo/metabolismo , Genoma Viral/genética , Hepatite B/diagnóstico , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/crescimento & desenvolvimento , Vírus da Hepatite B/metabolismo , Transcrição Reversa , Ribonuclease H/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Replicação Viral/genética
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