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1.
Toxicology ; 508: 153924, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39147091

RESUMEN

Nicotine, the primary constituent of tobacco, is one of the important factors that induce the occurrence of hepatocellular carcinoma (HCC). The ß2-adrenergic receptor (ß2-AR) is implicated in the growth and advancement of tumors. However, the role of ß2-AR and its mediated cascades in nicotine-induced HCC remains unclear. This present study aims to observe the effects of nicotine on the proliferation, migration, and invasion of immortalized human liver epithelial (THLE-2) cells, as well as to explore the underlying mechanisms of action. The results of cell counting kit-8 (CCK-8) assay showed that 0.3125 µM nicotine had the ability to promote the proliferation of THLE-2 cells with a significant time-dependent manner. Therefore, THLE-2 cells were mainly selected for chronic treatment with 0.3125 µM nicotine in the later stage to cause transformation. After 30 passages of THLE-2 cells with 0.3125 µM nicotine treatment, chronic exposure to nicotine significantly enhanced the proliferation, metastasis, and invasion of cells. Besides, it also upregulated the intracellular levels of ß2-AR, phosphoinositide 3-kinase (PI3K), AKT, matrix metalloproteinase-2 (MMP-2) and Cyclin D1, as well as downregulated the expression of p53. More importantly, the ß2-AR/PI3K/AKT pathway was found to mediate the expression of MMP-2, Cyclin D1, and p53 in THLE-2 cells, playing a crucial role in their proliferation, migration, and invasion after continuous exposure to nicotine. Simply put, it demonstrated the role of ß2-AR/PI3K/AKT pathway in the transformation of THLE-2 cells induced by nicotine. This study could provide valuable insights into the relationship between nicotine and HCC. Additionally, it lays the groundwork for investigating potential anticancer treatments for liver cancer linked to tobacco consumption.

2.
Nat Mater ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112738

RESUMEN

Reusable point-of-care biosensors offer a cost-effective solution for serial biomarker monitoring, addressing the critical demand for tumour treatments and recurrence diagnosis. However, their realization has been limited by the contradictory requirements of robust reusability and high sensing capability to multiple interactions among transducer surface, sensing probes and target analytes. Here we propose a drug-mediated organic electrochemical transistor as a robust, reusable epidermal growth factor receptor sensor with striking sensitivity and selectivity. By electrostatically adsorbing protonated gefitinib onto poly(3,4-ethylenedioxythiophene):polystyrene sulfonate and leveraging its strong binding to the epidermal growth factor receptor target, the device operates with a unique refresh-in-sensing mechanism. It not only yields an ultralow limit-of-detection concentration down to 5.74 fg ml-1 for epidermal growth factor receptor but, more importantly, also produces an unprecedented regeneration cycle exceeding 200. We further validate the potential of our devices for easy-to-use biomedical applications by creating an 8 × 12 diagnostic drug-mediated organic electrochemical transistor array with excellent uniformity to clinical blood samples.

3.
Soft Robot ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963793

RESUMEN

In recent years, the exploration of worm-like robots has garnered much attention for their adaptability in confined environments. However, current designs face challenges in fully utilizing the mechanical properties of structures/materials to replicate the superior performance of real worms. In this article, we propose an approach to address this limitation based on the stacked Miura origami structure, achieving the seamless integration of structural design, mechanical properties, and robotic functionalities, that is, the mechanical properties originate from the geometric design of the origami structure and at the same time serve the locomotion capability of the robot. Three major advantages of our design are: the implementation of origami technology facilitates a more accessible and convenient fabrication process for segmented robotic skin with periodicity and flexibility, as well as robotic bristles with anchoring effect; the utilization of the Poisson's ratio effect for deformation amplification; and the incorporation of localized folding motion for continuous peristaltic locomotion. Utilizing the high geometric designability inherent in origami, our robot demonstrates customizable morphing and quantifiable mechanical properties. Based on the origami worm-like robot prototype, we experimentally verified the effectiveness of the proposed design in realizing the deformation amplification effect and localized folding motion. By comparing this to a conventional worm-like robot with discontinuous deformation, we highlight the merits of these mechanical properties in enhancing the robot's mobility. To sum up, this article showcases a bottom-up approach to robot development, including geometric design, mechanical characterization, and functionality realization, presenting a unique perspective for advancing the development of bioinspired soft robots.

4.
Cell Rep ; 43(7): 114460, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38996068

RESUMEN

Natural silks are renewable proteins with impressive mechanical properties and biocompatibility that are useful in various fields. However, the cellular and spatial organization of silk-secreting organs remains unclear. Here, we combined single-nucleus and spatially resolved transcriptomics to systematically map the cellular and spatial composition of the silk glands (SGs) of mulberry silkworms late in larval development. This approach allowed us to profile SG cell types and cell state dynamics and identify regulatory networks and cell-cell communication related to efficient silk protein synthesis; key markers were validated via transgenic approaches. Notably, we demonstrated the indispensable role of the ecdysone receptor (ultraspiracle) in regulating endoreplication in SG cells. Our atlas presents the results of spatiotemporal analysis of silk-secreting organ architecture late in larval development; this atlas provides a valuable reference for elucidating the mechanism of efficient silk protein synthesis and developing sustainable products made from natural silk.


Asunto(s)
Bombyx , Proteínas de Insectos , Larva , Seda , Transcriptoma , Animales , Bombyx/genética , Bombyx/metabolismo , Seda/metabolismo , Larva/metabolismo , Larva/genética , Transcriptoma/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Núcleo Celular/metabolismo , Receptores de Esteroides/metabolismo , Receptores de Esteroides/genética , Regulación del Desarrollo de la Expresión Génica , Perfilación de la Expresión Génica
5.
Ecotoxicol Environ Saf ; 282: 116686, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38971100

RESUMEN

Constituents of cigarette smoke are known to be carcinogens. Additionally, there is mounting evidence that the liver is an organ susceptible to tobacco carcinogenicity. Nicotine, the primary constituent of tobacco, plays a role in cancer progression. In our previous study, it was found that nicotine enhances the proliferation of a human normal fetal hepatic (WRL68) cell due to the activation of p53 mutation at Ser249 (p53-RS)/STAT1/CCND1 signaling pathway. Here, we further elucidated the mechanism of regulating this pathway. Firstly, dose-dependent increase of SETDB1 protein level in WRL68 cells upon exposure to nicotine (1.25, 2.5, and 5 µM), significantly enhanced cellular proliferation. In addition, the upregulation of SETDB1 protein was necessary for the nuclear translocation of p53-RS to establish a ternary complex with STAT1 and SETDB1, which facilitated p53-RS di-methylation at K370 (p53-RS/K370me2). After that, the activation of CCND1/PI3K/AKT pathway was initiated when STAT1 stability was enhanced by p53-RS/K370me2, ultimately resulting in cell proliferation. Altogether, the study revealed that the increase in SETDB1 expression could potentially have a significant impact on the activation of CCND1/PI3K/AKT pathway through p53-RS/K370me2, leading to the proliferation of WRL68 cells induced by nicotine, which could contribute to hepatocellular carcinoma for smokers. Besides, the results of this study provided a foundation for the development of anticancer therapies for cancers associated with tobacco use.


Asunto(s)
Proliferación Celular , Ciclina D1 , N-Metiltransferasa de Histona-Lisina , Nicotina , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Proteína p53 Supresora de Tumor , Humanos , Nicotina/toxicidad , Ciclina D1/metabolismo , Ciclina D1/genética , N-Metiltransferasa de Histona-Lisina/genética , Proliferación Celular/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal/efectos de los fármacos , Metilación/efectos de los fármacos , Línea Celular , Factor de Transcripción STAT1/metabolismo
6.
Bioresour Technol ; 407: 131097, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38986882

RESUMEN

Sponge iron (SFe) coupled with a sludge system has great potential for improving biological denitrification; however, the underlying mechanism is not yet fully understood. In this study, the denitrification performance and microbial characteristics of ordinary sludge and SFe-sludge systems were investigated. Overall, the SFe-sludge reactor had faster ammonium degradation rate (94.0 %) and less nitrate accumulation (1.5-53.3 times lower) than ordinary reactor during the complete operation cycle of sequencing batch reactors. The addition of SFe increased the activities of nitrate and nitrite reductases. The total relative abundance of autotrophic denitrifying bacteria (Acidovorax, Arenimonas, etc.) in the SFe-sludge system after 38 days of operation was found to be 10.6 % higher than that in the ordinary sludge reactor. The aerobic denitrifying bacteria (Dokdonella, Phaeodactylibacter, etc.) was 5.3 % higher than ordinary sludge. The SFe-sludge system improved denitrification by enriching autotrophic/aerobic denitrifying bacteria in low carbon-to-nitrogen ratio wastewater treatment.


Asunto(s)
Procesos Autotróficos , Reactores Biológicos , Desnitrificación , Hierro , Aguas del Alcantarillado , Reactores Biológicos/microbiología , Aguas del Alcantarillado/microbiología , Hierro/metabolismo , Bacterias/metabolismo , Aerobiosis , Nitratos/metabolismo , Nitrógeno/metabolismo , Técnicas de Cultivo Celular por Lotes
7.
Nanoscale ; 16(26): 12309-12328, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38874095

RESUMEN

Compared to conventional heating techniques, the carbon carrier-based rapid Joule heating (CJH) method is a new class of technologies that offer significantly higher heating rates and ultra-high temperatures. Over the past few decades, CJH technology has spawned several techniques with similar principles for different application scenarios, including ultra-fast high temperature sintering (UHS), carbon thermal shock (CTS), and flash Joule heating (FJH), which have been widely used in material preparation research studies. Functional nanomaterials are a popular direction of research today, mainly including nanometallic materials, nanosilica materials, nanoceramic materials and nanocarbon materials. These materials exhibit unique physical, chemical, and biological properties, including a high specific surface area, strength, thermal stability, and biocompatibility, making them ideal for diverse applications across various fields. The CJH method is a remarkable approach to producing functional nanomaterials that has attracted attention for its significant advantages. This paper aims to delve into the fundamental principles of CJH and elucidate the efficient preparation of functional nanomaterials with superior properties using this technique. The paper is organized into three sections, each dedicated to introducing the process and characteristics of CJH technology for the preparation of three distinct material types: carbon-based nanomaterials, inorganic non-metallic materials, and metallic materials. We discuss the distinctions and merits of the CJH method compared to alternative techniques in the preparation of these materials, along with a thorough examination of their properties. Furthermore, the potential applications of these materials are highlighted. In conclusion, this paper concludes with a discussion on the future research trends and development prospects of CJH technology.

8.
Nat Nanotechnol ; 19(8): 1122-1129, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38649746

RESUMEN

Nanoresolved doping of polymeric semiconductors can overcome scaling limitations to create highly integrated flexible electronics, but remains a fundamental challenge due to isotropic diffusion of the dopants. Here we report a general methodology for achieving nanoscale ion-implantation-like electrochemical doping of polymeric semiconductors. This approach involves confining counterion electromigration within a glassy electrolyte composed of room-temperature ionic liquids and high-glass-transition-temperature insulating polymers. By precisely adjusting the electrolyte glass transition temperature (Tg) and the operating temperature (T), we create a highly localized electric field distribution and achieve anisotropic ion migration that is nearly vertical to the nanotip electrodes. The confined doping produces an excellent resolution of 56 nm with a lateral-extended doping length down to as little as 9.3 nm. We reveal a universal exponential dependence of the doping resolution on the temperature difference (Tg - T) that can be used to depict the doping resolution for almost infinite polymeric semiconductors. Moreover, we demonstrate its implications in a range of polymer electronic devices, including a 200% performance-enhanced organic transistor and a lateral p-n diode with seamless junction widths of <100 nm. Combined with a further demonstration in the scalability of the nanoscale doping, this concept may open up new opportunities for polymer-based nanoelectronics.

9.
Sci Rep ; 14(1): 6321, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491118

RESUMEN

To address issues of high water content and low calorific value during combustion of municipal sludge, we added water-absorbent, easy-to-burn agricultural waste to improve the overall combustion performance. Cotton straw or corn stover were added to the sludge and mixed at high-speed to compare their capacities for improving combustion performance. Scanning Electron Microscopy (SEM) revealed that cotton straw or corn stover attached to the surface of the municipal sludge particles after blending, while analysis of thermogravimetric curves and activation energies of the blends showed that combustion and exhaustion rates increased significantly when 40% cotton straw or corn stover were blended into the sludge. Using the quadrilateral cut-ring boiler as a prototype, the mix of sludge with cotton straw or corn stover was simulated, and FLUENT software was used to obtain the temperature and pollutant emissions of the boiler. Sludge blended with cotton straw or corn stover increased furnace temperature and reduced SO2 and NO emissions, while that with cotton straw burned at higher temperatures with lower SO2 and NO emissions. Overall, the CO content of sludge combustion was lower when blended with proportions of cotton straw or corn stover under 50%. The findings of this study lay a theoretical foundation for treatment of municipal sludge according to local conditions.

10.
Genes (Basel) ; 15(3)2024 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-38540379

RESUMEN

Toona ciliata is a deciduous or semi-deciduous tree species and belongs to the Toona genus of the Meliaceae family. Owing to low natural regeneration and over-exploitation, the species is listed as an endangered species at level II in China and its conservation has received increasing concern. Here, we sampled 447 individuals from 29 populations across the range-wide distribution of the T. ciliata complex in China and assessed their genetic variation using two chloroplast DNA markers. The results showed that the overall haplotype diversity and nucleotide diversity per site were high at h = 0.9767 and π = 0.0303 for the psbA-trnH fragment and h= 0.8999 and π = 0.0189 for the trnL-trnL fragment. Phylogenetic analysis supported the division of the natural distribution of T. ciliata complex into western and eastern regions. The genetic diversity was higher in the western region than in the eastern region, showing significant phylogeographic structure. Genetic differentiation among populations was moderate (Φst=42.87%), and the effects of isolation by distance (IBD) were significant. A neutrality test and mismatch distribution analysis indicated that the distribution of the T. ciliata complex generally did not expand, although a few local populations could likely expand after bottleneck effects. The overall results were complementary to and consolidated previous studies using mitochondrial and nuclear DNA markers. We finally discussed strategies for the genetic conservation of the T. ciliata complex.


Asunto(s)
Meliaceae , Humanos , Meliaceae/genética , Toona/genética , ADN de Cloroplastos/genética , Variación Genética/genética , Filogenia , Marcadores Genéticos
11.
Plants (Basel) ; 13(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38337968

RESUMEN

Forest genetic conservation is typically species-specific and does not integrate interspecific interaction and community structure. It mainly focuses on the theories of population and quantitative genetics. This approach depicts the intraspecific patterns of population genetic structure derived from genetic markers and the genetic differentiation of adaptive quantitative traits in provenance trials. However, it neglects possible interspecific interaction in natural forests and overlooks natural hybridization or subspeciation. We propose that the genetic diversity of a given species in a forest community is shaped by both intraspecific population and interspecific community evolutionary processes, and expand the traditional forest genetic conservation concept under the community ecology framework. We show that a community-specific phylogeny derived from molecular markers would allow us to explore the genetic mechanisms of a tree species interacting with other resident species. It would also facilitate the exploration of a species' ecological role in forest community assembly and the taxonomic relationship of the species with other species specific to its resident forest community. Phylogenetic ß-diversity would assess the similarities and differences of a tree species across communities regarding ecological function, the strength of selection pressure, and the nature and extent of its interaction with other species. Our forest genetic conservation proposal that integrates intraspecific population and interspecific community genetic variations is suitable for conserving a taxonomic species complex and maintaining its evolutionary potential in natural forests. This provides complementary information to conventional population and quantitative genetics-based conservation strategies.

12.
Sci Total Environ ; 912: 169604, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38157907

RESUMEN

Nicotine enters the environment mainly through human activity, as well as natural sources. This review article examines the increasing evidence implicating nicotine in the initiation and progression of lung cancer. Moreover, it primarily focuses on elucidating the activation mechanism of phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB, also known as AKT) signaling pathway, regulated by α7 subtype nicotinic acetylcholine receptor (α7-nAChR), in relation to the proliferation, invasion, and metastasis of lung cancer cells induced by nicotine, as well as nicotine-mediated anti-apoptotic effects. This process involves PI3K/AKT phosphorylated-B-cell lymphoma-2 (Bcl-2) family proteins, PI3K/AKT/mammalian target of rapamycin (mTOR), PI3K/AKT/nuclear factor-κB (NF-κB), hepatocyte growth factor (HGF)/cellular-mesenchymal epithelial transition factor (c-Met)-induced PI3K/AKT and PI3K/AKT activated-hypoxia-inducible factor-1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathways. In addition, we also deliberated on the related challenges and upcoming prospects within this field. These lay the foundation for further study on nicotine, lung tumorigenesis, and PI3K/AKT related molecular mechanisms. This work has the potential to significantly contribute to the treatment and prognosis of gastric cancer in smokers. Besides, the crucial significance of PI3K/AKT signaling pathway in multiple molecular pathways also suggests that its target antagonists may inhibit the development and progression of lung cancer, providing a possible new perspective for solving the problem of nicotine-promoted lung cancer. The emerging knowledge about the carcinogenic mechanisms of nicotine action should be considered during the environmental assessment of tobacco and other nicotine-containing products.


Asunto(s)
Neoplasias Pulmonares , Receptores Nicotínicos , Humanos , Neoplasias Pulmonares/patología , Nicotina/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptores Nicotínicos/fisiología , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
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