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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.
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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 TempoRESUMO
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.
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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.
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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/fisiologiaRESUMO
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 â¼190 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.
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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.
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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.
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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/genéticaRESUMO
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.
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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/genéticaRESUMO
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.
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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/metabolismoRESUMO
Although social species as diverse as humans and ants are among the most abundant organisms on Earth, animals cooperate and form groups for many reasons. How these different reasons for grouping affect a species' ecological dominance remains unknown. Here we use a theoretical model to demonstrate that the different fitness benefits that animals receive by forming groups depend on the quality of their environment, which in turn impacts their ecological dominance and resilience to global change. We then test the model's key predictions using phylogenetic comparative analysis of >6500 bird species. As predicted, we find that cooperative breeders occurring in harsh and fluctuating environments have larger ranges and greater abundances than non-cooperative breeders, but cooperative breeders occurring in benign and stable environments do not. Using our model, we further show that social species living in harsh and fluctuating environments will be less vulnerable to climate change than non-social species.
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Formigas , Comportamento Social , Animais , Humanos , Filogenia , Reprodução , Aves , Comportamento CooperativoRESUMO
Thermal interfaces are vital for effective thermal management in modern electronics, especially in the emerging fields of flexible electronics and soft robotics that impose requirements for interface materials to be soft and flexible in addition to having high thermal performance. Here, a novel sandwich-structured thermal interface material (TIM) is developed that simultaneously possesses record-low thermal resistance and high flexibility. Frequency-domain thermoreflectance (FDTR) is employed to investigate the overall thermal performance of the sandwich structure. As the core of this sandwich, a vertically aligned copper nanowire (CuNW) array preserves its high intrinsic thermal conductivity, which is further enhanced by 60% via a thick 3D graphene (3DG) coating. The thin copper layers on the top and bottom play the critical roles in protecting the nanowires during device assembly. Through the bottom-up fabrication process, excellent contacts between the graphene-coated CuNWs and the top/bottom layer are realized, leading to minimal interfacial resistance. In total, the thermal resistance of the sandwich is determined as low as ~0.23 mm2 K W-1 . This work investigates a new generation of flexible thermal interface materials with an ultralow thermal resistance, which therefore renders the great promise for advanced thermal management in a wide variety of electronics.
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Deforestation is a major contributor to biodiversity loss, yet the impact of forest loss on daily microclimate variability and its implications for species with different daily activity patterns remain poorly understood. Using a recently developed microclimate model, we investigated the effects of deforestation on the daily temperature range (DTR) in low-elevation tropical regions and high-elevation temperate regions. Our results show that deforestation substantially increases DTR in these areas, suggesting a potential impact on species interactions. To test this hypothesis, we studied the competitive interactions between nocturnal burying beetles and all-day-active blowfly maggots in forested and deforested habitats in Taiwan. We show that deforestation leads to increased DTR at higher elevations, which enhances the competitiveness of blowfly maggots during the day and leads to a higher failure rate of carcass burial by the beetles at night. Thus, deforestation-induced temperature variability not only modulates exploitative competition between species with different daily activity patterns, but also likely exacerbates the negative impacts of climate change on nocturnal organisms. In order to limit potential adverse effects on species interactions and their ecological functions, our study highlights the need to protect forests, especially in areas where deforestation can greatly alter temperature variability.
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Biodiversidade , Besouros , Animais , Temperatura , Mudança Climática , Febre , LarvaRESUMO
Tegument, which occupies the space between the nucleocapsid and the envelope, is a unique structure of a herpesvirion. Tegument proteins are major components of tegument and play critical roles in virus life cycle. Murine gammaherpesvirus 68 (MHV-68), a member of the gammaherpesvirus subfamily, is closely related to two human herpesviruses, Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV). We have previously shown that MHV-68 ORF33, conserved among all herpesviruses, encodes a tegument protein that is associated with intranuclear capsids and is essential for virion morphogenesis and egress. Another tegument protein ORF45, which is conserved only among gammaherpesviruses, also plays an essential role in virion morphogenesis of MHV-68. In this study, we investigated the underlying mechanism and showed that these two proteins colocalize and interact with each other during virus infection. We mapped the ORF33-interacting domain to the conserved carboxyl-terminal 23 amino acids (C23) of ORF45. Deletion of the C23 coding sequence in the context of viral genome abolished the production of infectious virions. Transmission electron microscopy results demonstrated that C23 of ORF45 are essential for virion tegumentation in the cytoplasm. We further mapped the ORF45-interacting domain to the N-terminal 17 amino acids (N17) of ORF33. Deletion of the N17 coding sequence in the context of viral genome also abolished production of infectious virions, and N17 of ORF33 are also essential for virion tegumentation in the cytoplasm. Taken together, our data strongly indicate that the interaction between ORF45 and ORF33 plays an essential role in cytoplasmic maturation of MHV-68 virions. IMPORTANCE A critical step in viral lytic replication is the assembly of progeny viral particles. Herpesviruses are important pathogens. A herpesvirus particle comprises, from inside to outside, four layers: DNA core, capsid, tegument, and envelope. The tegument layer contains dozens of virally encoded tegument proteins, which play critical roles in virus assembly. Murine gammaherpesvirus 68 (MHV-68) is a tumor-associated herpesvirus and is closely related to Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus. We previously found that the absence of either tegument protein ORF33 or ORF45 inhibits the translocation of nucleocapsids to the cytoplasm and blocks virion maturation, but the underlying mechanism remained unclear. Here, we showed that ORF33 interacts with ORF45. We mapped their interaction domains and constructed viral mutants with defects in ORF33-ORF45 interaction. Transmission electron microscopy data demonstrated that the assembly of these viral mutants in the cytoplasm is blocked. Our results indicate that ORF33-ORF45 interaction is essential for gammaherpesvirus replication.
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Proteínas do Capsídeo , Proteínas Imediatamente Precoces , Rhadinovirus , Montagem de Vírus , Animais , Camundongos , Citoplasma/metabolismo , Herpesvirus Humano 4 , Herpesvirus Humano 8 , Rhadinovirus/genética , Rhadinovirus/fisiologia , Vírion/genética , Vírion/fisiologia , Replicação Viral , Proteínas do Capsídeo/metabolismo , Proteínas Imediatamente Precoces/metabolismoRESUMO
Chronic HBV infection can hardly be cured due to the persistence of an intrahepatic pool of viral covalently closed circular DNA (cccDNA) transcription template, which is refractory to current antivirals. The direct analyses of cccDNA quantity and transcriptional activity require an invasive biopsy. Recently, circulating HBV RNA has been identified as a promising noninvasive surrogate marker of cccDNA and can be used for monitoring disease progression and predicting prognosis of patients with chronic HBV infection. To better understand this surrogate biomarker of cccDNA, we reviewed the current knowledge about the molecular characteristics and potential clinical applications of circulating HBV RNA. Specifically, we summarized the reported species and existing forms of circulating HBV RNA and discussed their biogenesis and the capacity of de novo infection by RNA virions. Moreover, we described the potential applications of circulating HBV RNA in different clinical scenarios, such as classifying the phases of chronic HBV infection, analyzing sustained on-treatment and off-treatment outcomes of treated patients, as well as predicting HCC development. Perspectives on future research of circulating HBV RNA were also proposed in this review.
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Carcinoma Hepatocelular , Ácidos Nucleicos Livres , Neoplasias Hepáticas , Humanos , Vírus da Hepatite B/genética , DNA Viral/genética , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , DNA Circular , Antivirais/uso terapêutico , RNA , Biomarcadores , Biologia , Replicação Viral/genéticaRESUMO
Hepatitis B Virus (HBV) replication has been reported to be restricted by the intrahepatic host restriction factors and antiviral signaling pathways. The intracellular mechanisms underlying the significant viremia difference among different phases of the natural history chronic HBV infection remain elusive. We herein report that the hypoxia-induced gene domain protein-1a (HIGD1A) was highly expressed in the liver of inactive HBV carriers with low viremia. Ectopic expression of HIGD1A in hepatocyte-derived cells significantly inhibited HBV transcription and replication in a dose-dependent manner, while silence of HIGD1A promoted HBV gene expression and replication. Similar results were also observed in both de novo HBV-infected cell culture model and HBV persistence mouse model. Mechanistically, HIGD1A is located on the mitochondrial inner membrane and activates nuclear factor kappa B (NF-κB) signaling pathway through binding to paroxysmal nonkinesigenic dyskinesia (PNKD), which further enhances the expression of a transcription factor NR2F1 to inhibit HBV transcription and replication. Consistently, knockdown of PNKD or NR2F1 and blockage of NF-κB signaling pathway abrogated the inhibitory effect of HIGD1A on HBV replication. Mitochondrial HIGD1A exploits the PNKD-NF-κB-NR2F1 nexus to act as a host restriction factor of HBV infection. Our study thus shed new lights on the regulation of HBV by hypoxia-related genes and related antiviral strategies.
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Vírus da Hepatite B , Hepatite B , Animais , Camundongos , Antivirais/farmacologia , Vírus da Hepatite B/fisiologia , NF-kappa B/genética , NF-kappa B/metabolismo , Transcrição Viral , Viremia , Replicação Viral , HumanosRESUMO
With the development of three-dimensional (3D) light-field display technology, 3D scenes with correct location information and depth information can be perceived without wearing any external device. Only 2D stylized portrait images can be generated with traditional portrait stylization methods and it is difficult to produce high-quality stylized portrait content for 3D light-field displays. 3D light-field displays require the generation of content with accurate depth and spatial information, which is not achievable with 2D images alone. New and innovative portrait stylization techniques methods should be presented to meet the requirements of 3D light-field displays. A portrait stylization method for 3D light-field displays is proposed, which maintain the consistency of dense views in light-field display when the 3D stylized portrait is generated. Example-based portrait stylization method is used to migrate the designated style image to the portrait image, which can prevent the loss of contour information in 3D light-field portraits. To minimize the diversity in color information and further constrain the contour details of portraits, the Laplacian loss function is introduced in the pre-trained deep learning model. The three-dimensional representation of the stylized portrait scene is reconstructed, and the stylized 3D light field image of the portrait is generated the mask guide based light-field coding method. Experimental results demonstrate the effectiveness of the proposed method, which can use the real portrait photos to generate high quality 3D light-field portrait content.
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14-3-3 proteins are ubiquitous adapters combining with phosphorylated serine/threonine motifs to regulate multiple cellular processes. As a negative regulator, 14-3-3 proteins could sequester the phosphorylated YAP1 in cytoplasm to inhibit its activity. In this study, we identified the K50 acetylation (K50ac) of 14-3-3ε protein and investigated its roles and mechanism in cholangiocarcinoma progression. The NAD (+)-dependent protein deacetylases inhibitor, NAM treatment significantly up-regulated the K50ac of 14-3-3ε. K50R mutation resulted in the decrease of K50ac of 14-3-3ε. The K50ac of 14-3-3ε was reversibly mediated by PCAF acetyltransferase and sirt1 deacetylases. K50ac had no obvious effect on the protein stability of 14-3-3ε, but inhibited the combination of 14-3-3ε with phosphorylated YAP1, which resulted in the activation of YAP1 in cholangiocarcinoma. K50R significantly decreased cholangiocarcinoma cell proliferation in vitro and the growth of tumor xenograft in vivo compared with WT (wild type) 14-3-3ε. The level of K50ac were higher in cholangiocarcinoma tissues accompanied by the accumulation of YAP1 in nuclear than para-carcinoma tissues. Our study revealed the underlying mechanism of K50ac of 14-3-3ε and its roles in cholangiocarcinoma, providing a potential targeting for cholangiocarcinoma therapy.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Acetilação , Colangiocarcinoma/metabolismo , Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Linhagem Celular TumoralRESUMO
Cholesterol 25-hydroxylase (CH25H) is an interferon (IFN)-stimulated gene that shows broad antiviral activities against a wide range of enveloped viruses. Here, using an IFN-stimulated gene screen against vesicular stomatitis virus (VSV)-SARS-CoV and VSV-SARS-CoV-2 chimeric viruses, we identified CH25H and its enzymatic product 25-hydroxycholesterol (25HC) as potent inhibitors of SARS-CoV-2 replication. Internalized 25HC accumulates in the late endosomes and potentially restricts SARS-CoV-2 spike protein catalyzed membrane fusion via blockade of cholesterol export. Our results highlight one of the possible antiviral mechanisms of 25HC and provide the molecular basis for its therapeutic development.
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Tratamento Farmacológico da COVID-19 , Endossomos/genética , Hidroxicolesteróis/farmacologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Antivirais/farmacologia , COVID-19/metabolismo , COVID-19/patologia , COVID-19/virologia , Endossomos/metabolismo , Humanos , Interferons/metabolismo , Fusão de Membrana/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/efeitos dos fármacos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/genética , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacosRESUMO
Few-shot semantic segmentation has attracted much attention because it requires only a few labeled samples to achieve good segmentation performance. However, existing methods still suffer from insufficient contextual information and unsatisfactory edge segmentation results. To overcome these two issues, this paper proposes a multi-scale context enhancement and edge-assisted network (called MCEENet) for few-shot semantic segmentation. First, rich support and query image features were extracted, respectively, using two weight-shared feature extraction networks, each consisting of a ResNet and a Vision Transformer. Subsequently, a multi-scale context enhancement (MCE) module was proposed to fuse the features of ResNet and Vision Transformer, and further mine the contextual information of the image by using cross-scale feature fusion and multi-scale dilated convolutions. Furthermore, we designed an Edge-Assisted Segmentation (EAS) module, which fuses the shallow ResNet features of the query image and the edge features computed by the Sobel operator to assist in the final segmentation task. We experimented on the PASCAL-5i dataset to demonstrate the effectiveness of MCEENet; the results of the 1-shot setting and 5-shot setting on the PASCAL-5i dataset are 63.5% and 64.7%, which surpasses the state-of-the-art results by 1.4% and 0.6%, respectively.
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BACKGROUND: Whether serum hepatitis B virus (HBV) RNA associates with hepatocellular carcinoma (HCC) development in chronic hepatitis B (CHB) patients has not been fully elucidated. METHODS: We enrolled 2974 patients receiving nucleos(t)ide analogues (NAs) from a prospective, observational CHB cohort to investigate the effect of serum HBV RNA, measured at study entry (baseline), on HCC development, using Cox regression analyses. RESULTS: During median follow-up of 4.4 years, 90 patients developed HCC. Patients with detectable baseline HBV RNA (nâ =â 2072) exhibited significantly higher HCC risk than those with undetectable level (5-year HCC incidence estimated by Kaplan-Meier method: 4.1% versus 1.8%, Pâ =â .009; adjusted hazard ratio [aHR]â =â 2.21, Pâ =â .005). HBV RNA levels of 609-99 999 andâ ≥100 000 copies/mL were associated with incrementally increasing HCC risk (aHRâ =â 2.15 and 3.05, respectively; P for trendâ =â .003), compared to undetectable level (<609 copies/mL). Moreover, patients with single-detectable either HBV DNA or RNA and double-detectable DNA and RNA had 1.57- and 4.02-fold higher HCC risk, respectively, than those with double-undetectable DNA and RNA (P for trendâ =â .001). CONCLUSIONS: High-level HBV RNA is associated with increased HCC risk in NAs-treated patients. Achieving undetectable HBV RNA may contribute to better clinical outcomes, indicating it could be a valuable endpoint of anti-HBV treatment.
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Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Antivirais/farmacologia , Carcinoma Hepatocelular/epidemiologia , DNA Viral , Vírus da Hepatite B/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Humanos , Neoplasias Hepáticas/epidemiologia , Nucleosídeos/farmacologia , Estudos Prospectivos , RNARESUMO
Core-shell photoanodes have shown great potential for photoelectrochemical (PEC) water oxidation. However, the construction of a high-quality interface between the core and shell, as well as a highly catalytic surface, remains a challenge. Herein, guided by computation, we present a BiVO4 photoanode coated with ZnCoFe polyphthalocyanine using pyrazine as a coordination agent. The bidirectional axial coordination of pyrazine plays a dual role by facilitating intimate interfacial contact between BiVO4 and ZnCoFe polyphthalocyanine, as well as regulating the electron density and spin configuration of metal sites in ZnCoFe phthalocyanine, thereby promoting the potential-limiting step of *OOH desorption. The resulting photoanode displayed a high photocurrent density of 5.7±0.1â mA cm-2 at 1.23â VRHE . This study introduces a new approach for constructing core-shell photoanodes, and uncovers the key role of pyrazine axial coordination in modulating the catalytic activity of metal phthalocyanine.