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1.
Fundam Res ; 4(1): 103-112, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933835

RESUMO

Oceanic uptake and storage of anthropogenic CO2 (CANT) are regulated by ocean circulation and ventilation. To decipher the storage and redistribution of CANT in the western North Pacific, where a major CANT sink develops, we investigated the water column carbonate system, dissolved inorganic radiocarbon and ancillary parameters in May and August 2018, spanning the Kuroshio Extension (KE, 35-39 °N), Kuroshio Recirculation (KR, 27-35 °N) and subtropical (21-27 °N) zones. Water column CANT inventories were estimated to be 40.5 ± 1.1 mol m-2 in the KR zone and 37.2 ± 0.9 mol m-2 in the subtropical zone. In comparison with historical data obtained in 2005, relatively high rates of increase of the CANT inventory of 1.05 ± 0.20 and 1.03 ± 0.12 mol m-2 yr-1 in the recent decade were obtained in the KR and subtropical zones, respectively. Our water-mass-based analyses suggest that formation and transport of subtropical mode water dominate the deep penetration, storage, and redistribution of CANT in those two regions. In the KE zone, however, both the water column CANT inventory and the decadal CANT accumulation rate were small and uncertain owing to the dynamic hydrology, where the naturally uplifting isopycnal surfaces make CANT penetration relatively shallow. The findings of this study improve the understanding of the spatiotemporal variations of CANT distribution, storage, and transport in the western North Pacific.

2.
Front Vet Sci ; 11: 1399776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38868501

RESUMO

Poultry broodiness can cause ovarian atresia, which has a detrimental impact on egg production. Non-coding RNAs (ncRNAs) have become one of the most talked-about topics in life sciences because of the increasing evidence of their novel biological roles in regulatory systems. However, the molecular mechanisms of ncRNAs functions and processes in chicken ovarian development remain largely unknown. Whole-transcriptome RNA sequencing of the ovaries of broodiness and laying chickens was thus performed to identify the ncRNA regulatory mechanisms associated with ovarian atresia in chickens. Subsequent analysis revealed that the ovaries of laying chickens and those with broodiness had 40 differentially expressed MicroRNA (miRNAs) (15 up-regulated and 25 down-regulated), 379 differentially expressed Long Noncoding RNA (lncRNAs) (213 up-regulated and 166 down-regulated), and 129 differentially expressed circular RNA (circRNAs) (63 up-regulated and 66 down-regulated). The competing endogenous RNAs (ceRNA) network analysis further revealed the involvement of ECM-receptor interaction, AGE-RAGE signaling pathway, focal adhesion, cytokine-cytokine receptor interaction, inflammatory mediator regulation of TRP channels, renin secretion, gap junction, insulin secretion, serotonergic synapse, and IL-17 signaling pathways in broodiness. Upon further analysis, it became evident that THBS1 and MYLK are significant candidate genes implicated in the regulation of broodiness. The expression of these genes is linked to miR-155-x, miR-211-z, miR-1682-z, gga-miR-155, and gga-miR-1682, as well as to the competitive binding of novel_circ_014674 and MSTRG.3306.4. The findings of this study reveal the existence of a regulatory link between non-coding RNAs and their competing mRNAs, which provide a better comprehension of the ncRNA function and processes in chicken ovarian development.

3.
Nat Commun ; 15(1): 4897, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851742

RESUMO

DNA base editors enable direct editing of adenine (A), cytosine (C), or guanine (G), but there is no base editor for direct thymine (T) editing currently. Here we develop two deaminase-free glycosylase-based base editors for direct T editing (gTBE) and C editing (gCBE) by fusing Cas9 nickase (nCas9) with engineered human uracil DNA glycosylase (UNG) variants. By several rounds of structure-informed rational mutagenesis on UNG in cultured human cells, we obtain gTBE and gCBE with high activity of T-to-S (i.e., T-to-C or T-to-G) and C-to-G conversions, respectively. Furthermore, we conduct parallel comparison of gTBE/gCBE with those recently developed using other protein engineering strategies, and find gTBE/gCBE show the outperformance. Thus, we provide several base editors, gTBEs and gCBEs, with corresponding engineered UNG variants, broadening the targeting scope of base editors.


Assuntos
Proteína 9 Associada à CRISPR , Edição de Genes , Engenharia de Proteínas , Uracila-DNA Glicosidase , Humanos , Edição de Genes/métodos , Uracila-DNA Glicosidase/metabolismo , Uracila-DNA Glicosidase/genética , Engenharia de Proteínas/métodos , Proteína 9 Associada à CRISPR/metabolismo , Proteína 9 Associada à CRISPR/genética , Citosina/metabolismo , Timina/metabolismo , Sistemas CRISPR-Cas , Células HEK293 , Mutagênese , Guanina/metabolismo , DNA/metabolismo , DNA/genética
4.
Sci Rep ; 14(1): 5582, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448540

RESUMO

This study presents a data-driven assisted real-time optimization model which is an innovative approach to address the challenges posed by integrating Submerged Arc Furnace (SAF) systems with renewable energy sources, specifically photovoltaic (PV) and wind power, with modern intelligent energy terminals. Specifically, the proposed method is divided into two stages. The first stage is related to data-driven prediction for addressing local time-varying renewable energy and electricity market prices with predicted information, and the second stage uses an optimization model for real-time SAF dispatch. Connections between intelligent energy terminals, demand-side devices, and load management systems are established to enhance local renewable resource utilization. Additionally, mathematical formulations of the operating resistance in SAF are explored, and deep neuron networks are employed and modified for dynamic uncertainty prediction. The proposed approach is validated through a case study involving an intelligent energy terminal with a 12.5 MVA SAF system and 12 MW capacity renewable generators in an electricity market with fluctuating prices. The findings of this research underscore the efficacy of the proposed optimization model in reducing operational costs and enhancing the utilization of localized renewable energy generation. By integrating four distinct dissatisfaction coefficients into the optimization framework, we demonstrate the model's adaptability and efficiency. The application of the optimization strategy delineated herein results in the SAF system's profitability oscillating between $111 and $416 across various time intervals, contingent upon the coefficient settings. Remarkably, an aggregate daily loss recovery amounting to $1,906.84 can be realized during the optimization period. Such outcomes not only signify considerable economic advantages but also contribute to grid stability and the diminution of renewable energy curtailment, thereby underscoring the dual benefits of economic efficiency and sustainability in energy management practices.

7.
Environ Sci Technol ; 57(15): 6216-6227, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37019690

RESUMO

Black carbon (BC), a group of environmentally concentrated organic pollutants, is widely distributed in marine sediments via riverine run-off and atmospheric deposition. The fate of BC transformation and cycling in marine sediments, however, has not been well studied. Here, we present radiocarbon measurements for sedimentary solid-phase BC (SBC) and porewater-dissolved BC (DBC) in surface sediments collected from the Yangtze and Yellow River estuaries and their adjacent coastal regions. Radiocarbon results revealed that two distinct BC pools in the sediments of the SBC had ancient radiocarbon ages (7110-15,850 years BP) that were 5370-14,935 years older than the 14C ages of porewater DBC. Using a radiocarbon mass balance model, we calculated that modern biomass-derived BC contributed 77-97% of the DBC pool and that fossil material-produced BC accounted for 61-87% of the SBC pools. This discrepancy between modern and dead BC contributions was associated with the BC budget after particulate BC (PBC) deposition; 38 ± 13% of the PBC was transferred to porewater as DBC and 62 ± 13% was sequestrated as SBC in sediments, serving as an important CO2 sink in marine sediments. We also provide evidence suggesting that DBC likely comprises some very fine particulate forms that are not completely dissolved as molecules. The nature and transformation mechanisms of DBC in natural aquatic systems need to be further studied.


Assuntos
Carbono , Poluentes Químicos da Água , Sedimentos Geológicos , Rios , Estuários , Poluentes Químicos da Água/análise , Fuligem , Poeira , Monitoramento Ambiental
8.
Sci Adv ; 9(14): eadg7541, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37018399

RESUMO

Photonic time crystals are artificial materials whose electromagnetic properties are uniform in space but periodically vary in time. The synthesis of these materials and experimental observation of their physics remain very challenging because of the stringent requirement for uniform modulation of material properties in volumetric samples. In this work, we extend the concept of photonic time crystals to two-dimensional artificial structures-metasurfaces. We demonstrate that time-varying metasurfaces not only preserve key physical properties of volumetric photonic time crystals despite their simpler topology but also host common momentum bandgaps shared by both surface and free-space electromagnetic waves. On the basis of a microwave metasurface design, we experimentally confirmed the exponential wave amplification inside a momentum bandgap and the possibility to probe bandgap physics by external (free-space) excitations. The proposed metasurface serves as a straightforward material platform for realizing emerging photonic space-time crystals and as a realistic system for the amplification of surface-wave signals in future wireless communications.

9.
Opt Lett ; 48(4): 1032-1035, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791003

RESUMO

Generalized duality transformations significantly modify the constitutive relations of electromagnetic media, preserving principal electromagnetic properties. Here, we contemplate transformation of Tellegen nihility as a specific type of extreme-property nonreciprocal bi-isotropic media and show that some intriguing electromagnetic properties of that medium can be realized in a particular class of isotropic magnetodielectric media without magnetoelectric coupling. We show that the permittivity and permeability of the corresponding transformed medium have equal absolute values and opposite signs. Depending on the value of the Tellegen parameter of the original medium, the transformed magnetodielectric medium can be Hermitian, non-Hermitian, or anti-Hermitian, which simultaneously exhibits loss and gain. Focusing on the latter class of anti-Hermitian media, we theoretically and numerically demonstrate that this extraordinary medium allows propagation of electromagnetic plane waves having zero time-averaged Poynting vector, similarly to the original Tellegen nihility media. Hopefully, this work can open novel opportunities for manipulating electromagnetic fields.

10.
Nat Biotechnol ; 41(8): 1080-1084, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36624150

RESUMO

Here we developed an adenine transversion base editor, AYBE, for A-to-C and A-to-T transversion editing in mammalian cells by fusing an adenine base editor (ABE) with hypoxanthine excision protein N-methylpurine DNA glycosylase (MPG). We also engineered AYBE variants enabling targeted editing at genomic loci with higher transversion editing activity (up to 72% for A-to-C or A-to-T editing).


Assuntos
Adenina , DNA Glicosilases , Animais , Adenina/metabolismo , Edição de Genes , Reparo do DNA/genética , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Mamíferos
12.
Nat Biotechnol ; 41(1): 108-119, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35953673

RESUMO

CRISPR-Cas13 systems have recently been used for targeted RNA degradation in various organisms. However, collateral degradation of bystander RNAs has limited their in vivo applications. Here, we design a dual-fluorescence reporter system for detecting collateral effects and screening Cas13 variants in mammalian cells. Among over 200 engineered variants, several Cas13 variants including Cas13d and Cas13X exhibit efficient on-target activity but markedly reduced collateral activity. Furthermore, transcriptome-wide off-targets and cell growth arrest induced by Cas13 are absent for these variants. High-fidelity Cas13 variants show similar RNA knockdown activity to wild-type Cas13 but no detectable collateral damage in transgenic mice or adeno-associated-virus-mediated somatic cell targeting. Thus, high-fidelity Cas13 variants with minimal collateral effects are now available for targeted degradation of RNAs in basic research and therapeutic applications.


Assuntos
Sistemas CRISPR-Cas , RNA , Animais , Camundongos , Sistemas CRISPR-Cas/genética , RNA/genética , Estabilidade de RNA/genética , Camundongos Transgênicos , Transcriptoma , Mamíferos/genética
13.
Environ Sci Technol ; 56(19): 14198-14207, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36125427

RESUMO

Deposition of atmospheric particulates is a major pathway for transporting materials from land to the ocean, with important implications for climate and nutrient cycling in the ocean. Here, we report the results of year-round measurements of particulate organic carbon (POC) and black carbon (BC) in atmospheric aerosols collected on Tuoji Island in the coastal Bohai-Yellow Sea of China (2019-2020) and during a cruise in the western North Pacific. Aerosol POC contents ranged from 1.9 to 11.9%; isotope values ranged from -18.8 to -29.0‰ for δ13C and -150 to -892‰ for Δ14C, corresponding to 14C ages of 1,235 to 17,780 years before present (BP). Mass balance calculations indicated that fossil carbon contributed 19-66% of the POC, with highest values in winter. BC produced from fossil fuel combustion accounted for 18-54% of the POC. "Old" BC (mean 6,238 ± 740 yr BP) was the major contributor to POC, and the old ages of aerosol POC were consistent with the 14C ages of total OC preserved in surface sediments of the Bohai-Yellow Sea and East China Sea. We conclude that atmospheric deposition is an important source of aged OC sequestered in marginal sea sediments and thus represents an important sink for carbon dioxide from the atmosphere.


Assuntos
Dióxido de Carbono , Monitoramento Ambiental , Aerossóis/análise , China , Carvão Mineral , Combustíveis Fósseis , Oceanos e Mares , Fuligem
14.
Sci Total Environ ; 851(Pt 1): 158123, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988614

RESUMO

Tibetan Plateau lakes are sensitive to climate variabilities and affect regional temperature, precipitation and ecosystems. In this study, we investigated the concentrations and carbon isotope (14C and 13C) compositions of dissolved organic and inorganic carbon (DOC and DIC) along with the concentrations of major lithologic ions (Na+, Mg2+, K+, Ca2+) and dissolved silicate (DSi) in a large lake, namely, Qinghai Lake, and its seven inflowing rivers on the northeastern Qinghai-Tibetan Plateau of China. Our results revealed large differences in concentrations and isotopic compositions between DOC and DIC, as well as differences in the concentrations of major ions between the rivers and lake. The chemical weathering of carbonate and silicates in the catchments played important roles in controlling the fates of major ions in the rivers. In Qinghai Lake, evaporation resulted in 40-290 times the accumulation of Na+, Mg2+, and K+ observed in the rivers, while biological uptake and precipitation reduced the concentrations of Ca2+ and DSi in the lake by 4-17 times compared with those in the rivers. In addition, the concentrations of DOC and DIC in the lake were 6-7 times those in the rivers. The carbon isotope (δ13C and Δ14C) signatures of DOC and DIC revealed that the rivers transport millennium-aged DOC (1254 ± 316 years) and DIC (1513 ± 857 years), as influenced largely by the chemical weathering of rocks and preaged soil carbon on the plateau. In contrast, in Qinghai Lake, the ages of DOC are significantly younger (684 ± 378 years) than the ages of riverine DOC, as regulated by newly biologically produced modern DOC. Moreover, the DIC ages in Qinghai Lake are all modern, indicating that exchange with atmospheric CO2 is the dominant process controlling the lake DIC. The accumulation and removal of riverine-aged DIC in Qinghai Lake, however, are not well understood, and the unbalanced radiocarbon in lake DIC remains a mystery that needs further study.


Assuntos
Ecossistema , Lagos , Carbono/análise , Dióxido de Carbono , Isótopos de Carbono/análise , Carbonatos , Monitoramento Ambiental , Lagos/química , Rios/química , Silicatos , Solo , Tibet
15.
Mol Ther Oncolytics ; 25: 236-248, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35615266

RESUMO

To date, diverse combination therapies with immune checkpoint inhibitors (ICIs), particularly oncolytic virotherapy, have demonstrated enhanced therapeutic outcomes in cancer treatment. However, high pre-existing immunity against the widely used adenovirus human serotype 5 (AdHu5) limits its extensive clinical application. In this study, we constructed an innovative oncolytic virus (OV) based on a chimpanzee adenoviral vector with low seropositivity in the human population, named AdC68-spE1A-αPD-1, which endows the parental OV (AdC68-spE1A-ΔE3) with the ability to express full-length anti-human programmed cell death-1 monoclonal antibody (αPD-1). In vitro studies indicated that the AdC68-spE1A-αPD-1 retained parental oncolytic capacity, and αPD-1 was efficiently secreted from the infected tumor cells and bound exclusively to human PD-1 (hPD-1) protein. In vivo, intratumoral treatment with AdC68-spE1A-αPD-1 resulted in significant tumor suppression, prolonged overall survival, and enhanced systemic antitumor memory response in an hPD-1 knockin mouse tumor model. This strategy outperformed the unarmed OV and was comparable with combination therapy with intratumoral injection of AdC68-spE1A-ΔE3 and systemic administration of commercial αPD-1. In summary, AdC68-spE1A-αPD-1 is a cost-effective approach with potential clinical applications. ‬‬‬‬.

16.
ACS Appl Mater Interfaces ; 14(9): 11177-11191, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35192338

RESUMO

Silk sutures with antibacterial and anti-inflammatory functions were developed for sustained dual-drug delivery to prevent surgical site infections (SSIs). The silk sutures were prepared with core-shell structures braided from degummed silk filaments and then coated with a silk fibroin (SF) layer loaded with berberine (BB) and artemisinin (ART). Both the rapid release of drugs to prevent initial biofilm formation and the following sustained release to maintain effective concentrations for more than 42 days were demonstrated. In vitro assays using human fibroblasts (Hs 865.Sk) demonstrated cell proliferation on the materials, and hemolysis was 2.4 ± 0.8%, lower than that required by ISO 10993-4 standard. The sutures inhibited platelet adhesion and promoted collagen deposition and blood vessel formation. In vivo assessments using Sprague-Dawley (SD) rats indicated that the coating reduced the expression of pro-inflammatory cytokines interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α), shortening the inflammatory period and promoting angiogenesis. The results demonstrated that these new sutures exhibited stable structures, favorable biocompatibility, and sustainable antibacterial and anti-inflammatory functions with potential for surgical applications.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Seda/química , Seda/farmacologia , Infecção da Ferida Cirúrgica/prevenção & controle , Suturas , Animais , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Artemisininas/química , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Berberina/química , Berberina/farmacologia , Berberina/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Quimioterapia Combinada/métodos , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Masculino , Fenômenos Físicos , Ratos Sprague-Dawley , Seda/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/metabolismo , Infecção da Ferida Cirúrgica/patologia
18.
Biomed Res Int ; 2021: 9984357, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124268

RESUMO

Pediatric lymphoma is a kind of malignant tumor with high mortality. The complexity of pediatric lymphoma shows a great challenge for effective diagnosis and treatment. In order to meet the challenge, the combination of pseudotargeted and targeted metabolomics was used to analyze the serum metabolites in pediatric lymphoma patients and healthy controls for discovering the metabolites related to pediatric lymphoma. The serum samples were obtained from the treatment group (n = 43), the control group (n = 26), and the patients group (n = 18). A total of 17 serum metabolites, including carnitine, leucine, creatine, urea, (6Z,9Z,12Z)-octadecatrienoic acid, linoleate, octadecenoic acid, L-palmitoylcarnitine, hexadecanoic acid, tetradecanoic acid, (9Z)-hexadecenoic acid, uric acid, glucose, 1-methylnicotinamide, hypoxanthine, L-glutamine, and taurine, were found to be related to pediatric lymphoma. They could provide a scientific diagnostic basis and therapeutic target for pediatric lymphoma and elucidate the mechanism of pediatric lymphoma.


Assuntos
Biomarcadores Tumorais/sangue , Sistemas de Liberação de Medicamentos , Linfoma , Metaboloma , Metabolômica , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Linfoma/sangue , Linfoma/diagnóstico , Linfoma/tratamento farmacológico , Masculino
19.
Environ Int ; 155: 106687, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34144477

RESUMO

Increasing macroalgal blooms as a consequence of climate warming and coastal eutrophication have profound effects on the marine environment. The outbreaks of Ulva prolifera in the Yellow Sea of China occurring every summer since 2007 to present have formed the world's largest green tide. The green tide releases huge amounts of dissolved organic matter (DOM) to the seawater, causing an organic overload. However, how marine bacteria respond to this issue and the potential impact on the marine environment are still unclear. Here, we monitored the highly temporally resolved dynamics of marine bacterial community that occur in response to Ulva prolifera-derived DOM by performing a 168-h microcosm incubation experiment. DOM inputs significantly increased bacterial abundances within 6 h, decreased bacterial diversity and triggered clear community successions during the whole period of incubation. Vibrio of Gammaproteobacteria robustly and rapidly grew over short timescales (6-24 h), with its relative abundance accounting for up to 52.5% of active bacteria. From 24 to 48 h, some genera of Flavobacteriia grew rapidly, which was more conspicuous at a higher DOM concentration than at a lower concentration. The genus Donghicola of Alphaproteobacteria was predominant at later time points (>48 h). This bacterial community succession was accompanied by significant variations in the activity of 12 different extracellular enzymes, resulting in a rapid reduction of dissolved organic carbon by 74.5% within the first 36 h. In summary, our study demonstrates rapid successions of bacterial community and extracellular enzyme activity after DOM inputs, suggesting that the bacterial response to Ulva prolifera-derived organic matter may contribute to environmental restoration and may pose a health threat due to the bloom of potential pathogenic Vibrio.


Assuntos
Ulva , Bactérias , China , Eutrofização , Estações do Ano , Água do Mar
20.
ACS Biomater Sci Eng ; 7(6): 2845-2857, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34043327

RESUMO

Medical sutures with sustainable antibacterial properties can effectively inhibit pathogens, thus avoiding the occurrence of surgical site infection and reducing the recurrence of patients resulting in postoperative death. This paper describes a facile scalable antibacterial surgical suture with sustainable antibacterial function and fair mechanical and biocompatible properties using a simple, efficient, and eco-friendly method. Silk filaments were braided into a core-shell structure using a braiding machine, and then silk fibroin (SF) films loaded with different percentages of berberine (BB) were coated onto the surface of the suture. The drug-loaded sutures performed a slow drug-release profile of more than 7 days. Retention of the knot-pull tensile strength of all groups was above 87% during in vitro degradation within 42 days. The sutures had no toxicity to the cells' in vitro cytotoxicity. The results of the in vivo biocompatibility test showed mild inflammation and clear signs of supporting angiogenesis in the implantation site of the rats. This work provides a new route for achieving a BB-loaded and high-performance antibacterial suture, which is of great potential in applications for surgical operations.


Assuntos
Berberina , Fibroínas , Animais , Antibacterianos/farmacologia , Berberina/farmacologia , Humanos , Ratos , Seda , Suturas
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