Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 182
Filtrar
1.
Cell ; 184(5): 1377-1391.e14, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33545088

RESUMO

Rich fossil evidence suggests that many traits and functions related to terrestrial evolution were present long before the ancestor of lobe- and ray-finned fishes. Here, we present genome sequences of the bichir, paddlefish, bowfin, and alligator gar, covering all major early divergent lineages of ray-finned fishes. Our analyses show that these species exhibit many mosaic genomic features of lobe- and ray-finned fishes. In particular, many regulatory elements for limb development are present in these fishes, supporting the hypothesis that the relevant ancestral regulation networks emerged before the origin of tetrapods. Transcriptome analyses confirm the homology between the lung and swim bladder and reveal the presence of functional lung-related genes in early ray-finned fishes. Furthermore, we functionally validate the essential role of a jawed vertebrate highly conserved element for cardiovascular development. Our results imply the ancestors of jawed vertebrates already had the potential gene networks for cardio-respiratory systems supporting air breathing.


Assuntos
Evolução Biológica , Peixes/genética , Nadadeiras de Animais/fisiologia , Animais , Fenômenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/anatomia & histologia , Extremidades/fisiologia , Peixes/classificação , Genoma , Pulmão/anatomia & histologia , Pulmão/fisiologia , Filogenia , Receptores Odorantes/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Vertebrados/classificação , Vertebrados/genética
2.
Cell ; 184(5): 1362-1376.e18, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33545087

RESUMO

Lungfishes are the closest extant relatives of tetrapods and preserve ancestral traits linked with the water-to-land transition. However, their huge genome sizes have hindered understanding of this key transition in evolution. Here, we report a 40-Gb chromosome-level assembly of the African lungfish (Protopterus annectens) genome, which is the largest genome assembly ever reported and has a contig and chromosome N50 of 1.60 Mb and 2.81 Gb, respectively. The large size of the lungfish genome is due mainly to retrotransposons. Genes with ultra-long length show similar expression levels to other genes, indicating that lungfishes have evolved high transcription efficacy to keep gene expression balanced. Together with transcriptome and experimental data, we identified potential genes and regulatory elements related to such terrestrial adaptation traits as pulmonary surfactant, anxiolytic ability, pentadactyl limbs, and pharyngeal remodeling. Our results provide insights and key resources for understanding the evolutionary pathway leading from fishes to humans.


Assuntos
Adaptação Biológica , Evolução Biológica , Peixes/genética , Sequenciamento Completo do Genoma , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/fisiologia , Animais , Extremidades/anatomia & histologia , Extremidades/fisiologia , Peixes/anatomia & histologia , Peixes/classificação , Peixes/fisiologia , Filogenia , Fenômenos Fisiológicos Respiratórios , Sistema Respiratório/anatomia & histologia , Vertebrados/genética
3.
Nature ; 610(7933): 661-666, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36198794

RESUMO

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

4.
Mol Biol Evol ; 40(3)2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36805964

RESUMO

Freeze tolerance, the ability of an organism to survive internal ice formation, is a striking survival strategy employed by some ectotherms living in cold environments. However, the genetic bases of this remarkable adaptation are largely unknown. The Amur sleeper (Perccottus glenii), the only known freeze-tolerant fish species, can overwinter with its entire body frozen in ice. Here, we sequenced the chromosome-level genome of the Amur sleeper and performed comparative genomic, transcriptomic, and metabolomic analyses to investigate its strategies for surviving freezing. Evolutionary analysis suggested that the Amur sleeper diverged from its closest non-cold-hardy relative about 15.07 million years ago and has experienced a high rate of protein evolution. Transcriptomic and metabolomic data identified a coordinated and tissue-specific regulation of genes and metabolites involved in hypometabolism, cellular stress response, and cryoprotectant accumulation involved in freezing and thawing. Several genes show evidence of accelerated protein sequence evolution or family size expansion were found as adaptive responses to freezing-induced stresses. Specifically, genetic changes associated with cytoskeleton stability, cryoprotectant synthesis, transmembrane transport, and neuroprotective adaptations were identified as potentially key innovations that aid in freezing survival. Our work provides valuable resources and opportunities to unveil the molecular adaptations supporting freeze tolerance in ectothermic vertebrates.


Assuntos
Gelo , Perciformes , Animais , Congelamento , Multiômica , Vertebrados , Adaptação Fisiológica/fisiologia , Aclimatação/genética
5.
Mol Biol Evol ; 40(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247387

RESUMO

Recent genomic analyses of evolutionary radiations suggest that ancient introgression may facilitate rapid diversification and adaptive radiation. The loach genus Triplophysa, a genus with most species endemic to Tibetan Plateau, shows ecological diversity and rapid evolution and represents a potential example of adaptive radiation linked to the uplift of the Tibetan Plateau. Here, we interrogate the complex evolutionary history of Triplophysa fishes through the analysis of whole-genome sequences. By reconstructing the phylogeny of Triplophysa, quantifying introgression across this clade, and simulating speciation and migration processes, we confirm that extensive gene flow events occurred across disparate Triplophysa species. Our results suggest that introgression plays a more substantial role than incomplete lineage sorting in underpinning phylogenetic discordance in Triplophysa. The results also indicate that genomic regions affected by ancient gene flow exhibit characteristics of lower recombination rates and nucleotide diversity and may associate with selection. Simulation analysis of Triplophysa tibetana suggests that the species may have been affected by the Gonghe Movement in the third uplift of the Tibetan Plateau, resulting in founder effects and a subsequent reduction in Ne.


Assuntos
Altitude , Cipriniformes , Animais , Filogenia , Tibet , Cipriniformes/genética , Adaptação Fisiológica/genética
6.
Phys Rev Lett ; 132(23): 233802, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905673

RESUMO

Non-line-of-sight (NLOS) imaging has the ability to reconstruct hidden objects, allowing a wide range of applications. Existing NLOS systems rely on pulsed lasers and time-resolved single-photon detectors to capture the information encoded in the time of flight of scattered photons. Despite remarkable advances, the pulsed time-of-flight LIDAR approach has limited temporal resolution and struggles to detect the frequency-associated information directly. Here, we propose and demonstrate the coherent scheme-frequency-modulated continuous wave calibrated by optical frequency comb-for high-resolution NLOS imaging, velocimetry, and vibrometry. Our comb-calibrated coherent sensor presents a system temporal resolution at subpicosecond and its superior signal-to-noise ratio permits NLOS imaging of complex scenes under strong ambient light. We show the capability of NLOS localization and 3D imaging at submillimeter scale and demonstrate NLOS vibrometry sensing at an accuracy of dozen Hertz. Our approach unlocks the coherent LIDAR techniques for widespread use in imaging science and optical sensing.

7.
J Environ Manage ; 352: 120026, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38184873

RESUMO

The emission of large amounts of carbon dioxide has caused serious environmental problems and hindered the construction of a green and low-carbon society. Efficient carbon dioxide capture has become an important means to slow down global climate warming and achieve effective utilization of carbon dioxide. Membranes synthesized by electrospinning technology are becoming promising carbon capture materials due to their unique characteristics. This review describes the features of membranes prepared from available raw materials and presents their application performances in carbon capture. The preparation methods of various types of membrane materials with excellent capture performance are summarized, and the effects of electrospinning parameters on electrospun fibers are systematically analyzed. Furthermore, recommendations and expectations for further development of electrospun membranes for carbon capture applications are given. These works provide important references for an in-depth understanding of the development status of electrospun membranes in the field of carbon capture and for expanding future research.


Assuntos
Dióxido de Carbono , Aquecimento Global , Clima , Tecnologia
8.
Neuroimage ; 283: 120421, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37879424

RESUMO

Elevated impulsivity has been frequently reported in individuals with opioid addiction receiving methadone maintenance therapy (MMT), but the underlying neural mechanisms and cognitive subprocesses are not fully understood. We acquired functional magnetic resonance imaging (fMRI) data from 37 subjects with heroin addiction receiving long-term MMT and 33 healthy controls who performed a probabilistic reversal learning task, and measured their resting-state brain glucose using fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Subjects receiving MMT exhibited significantly elevated self-reported impulsivity, and computational modeling revealed a marked impulsive decision bias manifested as switching more frequently without available evidence. Moreover, this impulsive decision bias was associated with the dose and duration of methadone use, irrelevant to the duration of heroin use. During the task, the switch-related hypoactivation in the left rostral middle frontal gyrus was correlated with the impulsive decision bias while the function of reward sensitivity was intact in subjects receiving MMT. Using prior brain-wide receptor density data, we found that the highest variance of regional metabolic abnormalities was explained by the spatial distribution of µ-opioid receptors among 10 types of neurotransmitter receptors. Heightened impulsivity in individuals receiving prolonged MMT is manifested as atypical choice bias and noise in decision-making processes, which is further driven by deficits in top-down cognitive control, other than reward sensitivity. Our findings uncover multifaceted mechanisms underlying elevated impulsivity in subjects receiving MMT, which might provide insights for developing complementary therapies to improve retention during MMT.


Assuntos
Dependência de Heroína , Humanos , Dependência de Heroína/tratamento farmacológico , Metadona/uso terapêutico , Heroína/efeitos adversos , Encéfalo/diagnóstico por imagem , Comportamento Impulsivo
9.
Ann Rheum Dis ; 82(2): 198-211, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36198439

RESUMO

OBJECTIVES: To uncover the function and underlying mechanism of an essential transcriptional factor, PU.1, in the development of rheumatoid arthritis (RA). METHODS: The expression and localisation of PU.1 and its potential target, FMS-like tyrosine kinase 3 (FLT3), in the synovium of patients with RA were determined by western blot and immunohistochemical (IHC) staining. UREΔ (with PU.1 knockdown) and FLT3-ITD (with FLT3 activation) mice were used to establish collagen antibody-induced arthritis (CAIA). For the in vitro study, the effects of PU.1 and FLT3 on primary macrophages and fibroblast-like synoviocytes (FLS) were investigated using siRNAs. Mechanistically, luciferase reporter assays, western blotting, FACS and IHC were conducted to show the direct regulation of PU.1 on the transcription of FLT3 in macrophages and FLS. Finally, a small molecular inhibitor of PU.1, DB2313, was used to further illustrate the therapeutic effects of DB2313 on arthritis using two in vivo models, CAIA and collagen-induced arthritis (CIA). RESULTS: The expression of PU.1 was induced in the synovium of patients with RA when compared with that in osteoarthritis patients and normal controls. FLT3 and p-FLT3 showed opposite expression patterns compared with PU.1 in RA. The CAIA model showed that PU.1 was an activator, whereas FLT3 was a repressor, of the development of arthritis in vivo. Moreover, results from in vitro assays were consistent with the in vivo results: PU.1 promoted hyperactivation and inflammatory status of macrophages and FLS, whereas FLT3 had the opposite effects. In addition, PU.1 inhibited the transcription of FLT3 by directly binding to its promoter region. The PU.1 inhibitor DB2313 clearly alleviated the effects on arthritis development in the CAIA and CIA models. CONCLUSIONS: These results support the role of PU.1 in RA and may have therapeutic implications by directly repressing FLT3. Therefore, targeting PU.1 might be a potential therapeutic approach for RA.


Assuntos
Artrite Experimental , Artrite Reumatoide , Proteínas Proto-Oncogênicas , Sinoviócitos , Transativadores , Animais , Camundongos , Artrite Experimental/metabolismo , Artrite Reumatoide/tratamento farmacológico , Proliferação de Células , Células Cultivadas , Fibroblastos/metabolismo , Tirosina Quinase 3 Semelhante a fms/metabolismo , Tirosina Quinase 3 Semelhante a fms/farmacologia , Tirosina Quinase 3 Semelhante a fms/uso terapêutico , Membrana Sinovial/metabolismo , Sinoviócitos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo
10.
Cancer Cell Int ; 23(1): 333, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115111

RESUMO

DPY30 belongs to the core subunit of components of the histone lysine methyltransferase complex, which is implicated in tumorigenesis, cell senescence, and other biological events. However, its contribution to colorectal carcinoma (CRC) progression and metastasis has yet to be elucidated. Therefore, this study aimed to investigate the biological function of DPY30 in CRC metastasis both in vitro and in vivo. Herein, our results revealed that DPY30 overexpression is significantly positively correlated with positive lymph nodes, epithelial-mesenchymal transition (EMT), and CRC metastasis. Moreover, DPY30 knockdown in HT29 and SW480 cells markedly decreased EMT progression, as well as the migratory and invasive abilities of CRC cells in vitro and lung tumor metastasis in vivo. Mechanistically, DPY30 increased histone H3K4me3 level and promoted EMT and CRC metastasis by upregulating the transcriptional expression of ZEB1. Taken together, our findings indicate that DPY30 may serve as a therapeutic target and prognostic marker for CRC.

11.
Scand J Gastroenterol ; 58(12): 1466-1473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37525405

RESUMO

BACKGROUND: Recent studies have suggested a potential causal association between Interleukins (ILs) and Colorectal Cancer (CRC), and thus, it is important to examine the causal relationship between them using a Mendelian randomization (MR) approach. METHODS: The instrumental variables were extracted for IL-1ra, IL-6, IL-6ra, IL-8, IL-16, IL-18, IL-27 from genome-wide association studies of European ancestry. Summary statistics of CRC were also retrieved. An inverse variance-weighted MR approach was implemented as the primary method to compute overall effects from multiple instruments. Additional MR approaches and sensitivity and heterogeneity pleiotropy analyses were also conducted respectively. RESULTS: Our analysis suggested a causal effect between an increase of IL-8 and a reduced risk of CRC (odds ratio 0.65; 95% confidence interval, 0.43-0.98; p = 0.041) and did not provide evidence for causal effects of IL-1ra, IL-6, IL-6ra, IL-16, IL-18, IL-27. Sensitivity analyses suggested the robustness of MR results and that they were unlikely to be affected by unbalanced pleiotropy or significant heterogeneity. CONCLUSIONS: This study investigated the role of ILs in the development of CRC and we found a causal effect between an increase of IL-8 and a reduced risk of CRC but not found evidence for causal effects of IL-1ra, IL-6, IL-6ra, IL-16, IL-18, IL-27. Sensitivity analyses suggested the robustness of MR results and that they were unlikely to be affected by unbalanced pleiotropy or significant heterogeneity.


Assuntos
Neoplasias Colorretais , Interleucina-27 , Humanos , Interleucina-18/genética , Interleucina-16 , Proteína Antagonista do Receptor de Interleucina 1 , Estudo de Associação Genômica Ampla , Interleucina-6/genética , Interleucina-8/genética , Análise da Randomização Mendeliana , Interleucinas/genética , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética
12.
Int J Med Sci ; 20(7): 901-917, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324189

RESUMO

DPY30, a core subunit of the SET1/MLL histone H3K4 methyltransferase complexes, plays an important role in diverse biological functions through the epigenetic regulation of gene transcription, especially in cancer development. However, its involvement in human colorectal carcinoma (CRC) has not been elucidated yet. Here we demonstrated that DPY30 was overexpressed in CRC tissues, and significantly associated with pathological grading, tumor size, TNM stage, and tumor location. Furthermore, DPY30 knockdown remarkably suppressed the CRC cell proliferation through downregulation of PCNA and Ki67 in vitro and in vivo, simultaneously induced cell cycle arrest at S phase by downregulating Cyclin A2. In the mechanistic study, RNA-Seq analysis revealed that enriched gene ontology of cell proliferation and cell growth was significantly affected. And ChIP result indicated that DPY30 knockdown inhibited H3 lysine 4 trimethylation (H3K4me3) and attenuated interactions between H3K4me3 with PCNA, Ki67 and cyclin A2 respectively, which led to the decrease of H3K4me3 establishment on their promoter regions. Taken together, our results demonstrate overexpression of DPY30 promotes CRC cell proliferation and cell cycle progression by facilitating the transcription of PCNA, Ki67 and cyclin A2 via mediating H3K4me3. It suggests that DPY30 may serve as a potential therapeutic molecular target for CRC.


Assuntos
Neoplasias Colorretais , Ciclina A2 , Humanos , Ciclina A2/genética , Fatores de Transcrição , Epigênese Genética , Antígeno Ki-67 , Antígeno Nuclear de Célula em Proliferação , Proliferação de Células/genética , Ciclo Celular/genética , Neoplasias Colorretais/genética
13.
J Fish Dis ; 46(3): 261-271, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36504104

RESUMO

Largemouth bass virus (LMBV) is a systemic viral pathogen that can cause high mortality rates in cultivated largemouth bass. However, no treatment is currently approved. Therapeutic strategies against LMBV infection are urgently needed. In this study, we investigated the antiviral activity of piperine against LMBV in vitro and in vivo. In vitro antiviral activity assay showed that 210.28 µM piperine significantly decreased LMBV major capsid protein (MCP) gene expression in epithelioma papulosum cyprinid (EPC) cells by a maximum inhibitory rate of >95%. Piperine treatment inhibited LMBV replication in a dose-dependent manner, with the half-maximal activity (IC50 ) of 34.61 µM. Moreover, piperine significantly decreased the viral titers and cytopathic effects (CPE), contributing to the protection of infected cells. With regard to the steps of piperine affecting the life cycle of viruses, piperine had a direct inactivating effect on LMBV. During the virus adsorption phase, piperine prevented the adsorption of LMBV to EPC cells. Furthermore, piperine played an antiviral role mainly in the later stages of viral infection (4-8 h). To further evaluate the antiviral activity of piperine against LMBV in vivo, largemouth bass as a model organism was carried out in relevant experiments. Intraperitoneal injection of piperine (25 mg/kg) effectively improved the survival rate of LMBV-infected largemouth bass by 20%. In addition, RT-qPCR results of viral replication in liver, spleen, kidney, gill and swim bladder tissues showed that piperine significantly inhibited LMBV replication in vivo, thus protecting largemouth bass from LMBV-induced death. Together, our results suggested that piperine is a therapeutic and preventative agent against LMBV infection.


Assuntos
Bass , Infecções por Vírus de DNA , Doenças dos Peixes , Animais , Proteínas Virais , Aquicultura , Replicação Viral , Antivirais
14.
Angew Chem Int Ed Engl ; 62(13): e202218717, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728627

RESUMO

The aqueous electrocatalytic reduction of NO3 - into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<-0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 - and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L-1 at 10 mA cm-2 and a power density of 14.1 mW cm-2 , which is well beyond all previously reported similar concepts.

15.
Angew Chem Int Ed Engl ; 62(30): e202305695, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235524

RESUMO

Redox flow batteries have been discussed as scalable and simple stationary energy storage devices. However, currently developed systems encounter less competitive energy density and high costs, restricting their wider application. There is a lack of appropriate redox chemistry, preferably based on active materials that are abundant in nature and show high solubility in aqueous electrolytes. A nitrogen-centered redox cycle operating between the limiting species ammonia and nitrate via an eight-electron redox reaction stayed practically unnoticed, albeit its ubiquity in biological processes. Ammonia or nitrate are world-scale chemicals with high aqueous solubility, and are then comparably safe. We demonstrate here the successful implementation of such a nitrogen-based redox cycle between ammonia and nitrate with eight-electron transfer as a catholyte for Zn-based flow batteries, which continuously worked for 12.9 days with 930 charging-discharging cycles. A very competitive energy density of 577 Wh L-1 can be reached, which is well above most reported flow batteries (e.g. 8 times the standard Zn-bromide battery), demonstrating that the nitrogen cycle with eight-electron transfer can offer promising cathodic redox chemistry for safe, affordable, and scalable high-energy-density storage devices.

16.
Mol Biol Evol ; 38(6): 2413-2427, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33533895

RESUMO

Endothermy is a typical convergent phenomenon which has evolved independently at least eight times in vertebrates, and is of significant advantage to organisms in extending their niches. However, how vertebrates other than mammals or birds, especially teleosts, achieve endothermy has not previously been fully understood. In this study, we sequenced the genomes of two billfishes (swordfish and sailfish), members of a representative lineage of endothermic teleosts. Convergent amino acid replacements were observed in proteins related to heat production and the visual system in two endothermic teleost lineages, billfishes and tunas. The billfish-specific genetic innovations were found to be associated with heat exchange, thermoregulation, and the specialized morphology, including elongated bill, enlarged dorsal fin in sailfish and loss of the pelvic fin in swordfish.


Assuntos
Evolução Biológica , Perciformes/genética , Termogênese/genética , Nadadeiras de Animais/anatomia & histologia , Animais , Genoma , Masculino , Perciformes/anatomia & histologia , Fenótipo , Visão Ocular/genética
17.
J Fish Dis ; 45(11): 1599-1607, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35801398

RESUMO

Nocardiosis caused by Nocardia seriolae is a major threat to the aquaculture industry. Given that prolonged therapy administration can lead to a growth of antibiotic resistant strains, new antibacterial agents and alternative strategies are urgently needed. In this study, 80 medicinal plants were selected for antibacterial screening to obtain potent bioactive compounds against N. seriolae infection. The methanolic extracts of Magnolia officinalis exhibited the strongest antibacterial activity against N. seriolae with the minimal inhibitory concentration (MIC) of 12.5 µg/ml. Honokiol and magnolol as the main bioactive components of M. officinalis showed higher activity with the MIC value of 3.12 and 6.25 µg/ml, respectively. Sequentially, the evaluation of antibacterial activity of honokiol in vivo showed that honokiol had good biosafety, and could significantly reduce the bacterial load of nocardia-infected largemouth bass (p < .001). Furthermore, the survival rate of nocardia-infected fish fed with 100 mg/kg honokiol was obviously improved (p < .05). Collectively, these results suggest that medicinal plants represent a promising reservoir for discovering active components against Nocardia, and honokiol has great potential to be developed as therapeutic agents to control nocardiosis in aquaculture.


Assuntos
Bass , Doenças dos Peixes , Magnolia , Nocardiose , Nocardia , Plantas Medicinais , Compostos Alílicos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Compostos de Bifenilo , Doenças dos Peixes/tratamento farmacológico , Nocardiose/tratamento farmacológico , Nocardiose/veterinária , Fenóis , Extratos Vegetais/farmacologia
18.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36142360

RESUMO

The outbreak of white spot syndrome (WSS) is a looming challenge, due to dramatic losses to the crustacean aquaculture industry. However, at present, there are no prophylactic or therapeutic means to control this infectious viral disease. Here, we screened fifteen medicinal plants for their inhibitory activity on the white spot syndrome virus (WSSV), using red swamp crayfish (Procambarus clarkii) as a model species. The results showed that the crude extracts of Pinellia ternata (Thunb.) Breit. had the highest inhibitory effect (91.59%, 100 mg/kg) on WSSV proliferation, and its main component, beta-sitosterol, showed a much higher activity (95.79%, 50 mg/kg). Further, beta-sitosterol potently reduced (p < 0.01) viral loads and viral gene transcription levels in a concentration-dependent fashion, and significantly promoted the survival rate of WSSV-challenged crayfish (57.14%, 50 mg/kg). The co-incubation assay indicated that beta-sitosterol did not influence the infectivity of WSSV particles. Both pre- and post-treatment of beta-sitosterol exerted a significant inhibitory effect (p < 0.01) on the viral load in vivo. Mechanistically, beta-sitosterol not only interfered with the expression of viral genes (immediate early gene 1, ie1; DNA polymerase, DNApol) that are important in initiating WSSV transcription, but it also attenuated the hijacking of innate immune signaling pathways (Toll, IMD, and JAK/STAT pathways) by viral genes to block WSSV replication. Moreover, the expression of several antiviral immune, antioxidant, pro-inflammatory, and apoptosis-related genes changed significantly in beta-sitosterol-treated crayfish. Beta-sitosterol is a potent WSSV inhibitor and has the potential to be developed as an effective anti-WSSV agent against a WSS outbreak in crustacean aquaculture.


Assuntos
Vírus da Síndrome da Mancha Branca 1 , Animais , Antioxidantes/farmacologia , Antivirais/farmacologia , Astacoidea/genética , Misturas Complexas/farmacologia , Sitosteroides
19.
Entropy (Basel) ; 24(5)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35626619

RESUMO

When an unmanned aerial vehicle (UAV) performs tasks such as power patrol inspection, water quality detection, field scientific observation, etc., due to the limitations of the computing capacity and battery power, it cannot complete the tasks efficiently. Therefore, an effective method is to deploy edge servers near the UAV. The UAV can offload some of the computationally intensive and real-time tasks to edge servers. In this paper, a mobile edge computing offloading strategy based on reinforcement learning is proposed. Firstly, the Stackelberg game model is introduced to model the UAV and edge nodes in the network, and the utility function is used to calculate the maximization of offloading revenue. Secondly, as the problem is a mixed-integer non-linear programming (MINLP) problem, we introduce the multi-agent deep deterministic policy gradient (MADDPG) to solve it. Finally, the effects of the number of UAVs and the summation of computing resources on the total revenue of the UAVs were simulated through simulation experiments. The experimental results show that compared with other algorithms, the algorithm proposed in this paper can more effectively improve the total benefit of UAVs.

20.
Fish Shellfish Immunol ; 119: 432-441, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688864

RESUMO

White spot syndrome virus (WSSV) is a fatal pathogen threatening global crustacean industry with no commercially available drugs to control. Herbal medicines have been widely used to treat a number of viral infections, which could offer a rich reserve for antiviral drug discovery. Here, we evaluated the inhibition activities of 30 herbal medicines against WSSV in Chinese mitten crab Eriocheir sinensis. A WSSV infection model in E. sinensis was firstly established in order to determine the antiviral effects of the plant extracts and to explore the potential action mechanisms. Results showed that the highest anti-WSSV activity was obtained by the treatment of Ophiopogon japonicus extract (93.03%, 100 mg/kg). O. japonicus treatment decreased viral loads in a dose-dependent manner and significantly improved the survival of WSSV-challenged crabs. O. japonicus reduced the expression of vital genes in viral life cycle in vivo, particularly for the immediate-early stage gene ie1. Further results indicated that O. japonicus could repress the JAK-STAT signaling pathway to block ie1 transcription. Moreover, O. japonicus could modulate certain immune genes such as the myosin, toll-like receptor, crustin, and prophenoloxidase in the interactions between WSSV and crabs. The up-regulated expression of pro-autophagic factors (Gabarap and Atg7) and elevated levels of antioxidant enzymes (SOD, CAT and GSH) suggested that O. japonicus may induce autophagy and attenuate WSSV-induced oxidative stress. Taken together, O. japonicus could inhibit WSSV proliferation and improve the survival of WSSV-challenged crabs. Thus, O. japonicus may have the potential to be developed as a preventive or therapeutic agent against WSSV, and its effective compounds merit further isolation and identification.


Assuntos
Ophiopogon , Vírus da Síndrome da Mancha Branca 1 , Animais , Antivirais , Proteínas de Artrópodes/genética , Proliferação de Células , China , Imunidade Inata
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA