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1.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38474902

RESUMEN

Underwater optical imaging for information acquisition has always been an innovative and crucial research direction. Unlike imaging in the air medium, the underwater optical environment is more intricate. From an optical perspective, natural factors such as turbulence and suspended particles in the water cause issues like light scattering and attenuation, leading to color distortion, loss of details, decreased contrast, and overall blurriness. These challenges significantly impact the acquisition of underwater image information, rendering subsequent algorithms reliant on such data unable to function properly. Therefore, this paper proposes a method for underwater image restoration using Stokes linearly polarized light, specifically tailored to the challenges of underwater complex optical imaging environments. This method effectively utilizes linear polarization information and designs a system that uses the information of the first few frames to calculate the enhanced images of the later frames. By doing so, it achieves real-time underwater Stokes linear polarized imaging while minimizing human interference during the imaging process. Furthermore, the paper provides a comprehensive analysis of the deficiencies observed during the testing of the method and proposes improvement perspectives, along with offering insights into potential future research directions.

3.
Nat Prod Res ; : 1-7, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38084375

RESUMEN

A new sesquiterpene, named (1S, 4aS, 7 R, 8 R, 8aR) Decahydro-1,4a-dimethyl-7-(1-methylethyl)-1,8-naphthalenediol (1), and six known compounds (2-7) were obtained from Colletotrichum sp. B-89, an endophytic fungus isolated from Dracaena cochinchinensis collected at Xishuangbanna, Yunnan. Their structures were elucidated by detailed analysis of comprehensive spectroscopic data, and the structure of 1 was further determined by X-ray diffraction analysis. The antibacterial activities of above compounds were assayed and compound 6 exhibited certain activities against S. aureus ATCC 25923, B. subtilis ATCC 6633, E. coli ATCC 25922, and K. pneumoniae ATCC 13883.

4.
J Antibiot (Tokyo) ; 76(12): 735-740, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37789127

RESUMEN

Two new diketopiperazines, namely samsoniellain A (1) and samsoniellain B (2), together with two known compounds (3, 4) were isolated from Cordyceps fungus Samsoniella sp. XY4. The planar structures of 1 and 2 were determined by HRESIMS, 1D and 2D NMR spectroscopy. The absolute configurations of 1 and 2 were determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Results of antimicrobial activity indicated that compound 2 showed weak bacteriostatic activities against S. typhimurium χ 8956, H. influenza ATCC 10211, MRSA 2024 with the MIC values of 128, 256, and 256 µg ml-1, respectively. This is the first report about secondary metabolites of Samsoniella sp.


Asunto(s)
Cordyceps , Hypocreales , Cordyceps/química , Dicetopiperazinas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular
5.
Nat Prod Res ; : 1-11, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37378495

RESUMEN

Coronarin E is a main diterpene ever isolated from Hedychium yunnanense. With the aim to enlarge its potential application, four butenolide derivatives (compounds 4a, 4b, 5a and 5b) were obtained from coronarin E via synthetic method, and their antibacterial effects were also evaluated. It is noteworthy that compounds 5a and 5b exhibited stronger antibacterial activities against most of the tested bacterial strains than ampicillin and kanamycin, two first- and second-line antimicrobials in clinical. For example, minimum inhibitory concentration (MIC) of 5a, 5b, ampicillin and kanamycin against Acinetobacter baumanii were 2, 1, 8 and 4 µg/mL, respectively, and MIC of the four compounds mentioned above against Klebsiella pneumonia were 1, 0.5, 16 and 4 µg/mL, respectively. The current studies not only enrich the structural diversity of diterpenes derived from Hedychium genus, but also provide potent candidates for the development of antibacterial medicines.

6.
Bioinspir Biomim ; 18(3)2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36867873

RESUMEN

Biomimetic and bioinspired design is not only a potent resource for roboticists looking to develop robust engineering systems or understand the natural world. It is also a uniquely accessible entry point into science and technology. Every person on Earth constantly interacts with nature, and most people have an intuitive sense of animal and plant behaviour, even without realizing it. The Natural Robotics Contest is novel piece of science communication that takes advantage of this intuition, and creates an opportunity for anyone with an interest in nature or robotics to submit their idea and have it turned into a real engineering system. In this paper we will discuss the competition's submissions, which show how the public thinks of nature as well as the problems people see as most pressing for engineers to solve. We will then show our design process from the winning submitted concept sketch through to functioning robot, to offer a case study in biomimetic robot design. The winning design is a robotic fish which uses gill structures to filter out microplastics. This was fabricated into an open source robot with a novel 3D printed gill design. By presenting the competition and the winning entry we hope to foster further interest in nature-inspired design, and increase the interplay between nature and engineering in the minds of readers.


Asunto(s)
Colaboración de las Masas , Robótica , Animales , Biomimética , Plásticos , Conducta Animal , Diseño de Equipo
7.
Hepatol Int ; 17(4): 1016-1027, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36821045

RESUMEN

OBJECTIVES: In this multicenter study, we sought to develop and validate a preoperative model for predicting early recurrence (ER) risk after curative resection of intrahepatic cholangiocarcinoma (ICC) through artificial intelligence (AI)-based CT radiomics approach. MATERIALS AND METHODS: A total of 311 patients (Derivation: 160; Internal and two external validations: 36, 74 and 61) from 8 medical centers who underwent curative resection were collected retrospectively. In derivation cohort, radiomics and clinical-radiomics models for ER prediction were constructed by LightGBM (a machine learning algorithm). A clinical model was also developed for comparison. Model performance was validated in internal and two external cohorts by ROC. In addition, we investigated the interpretability of the LightGBM model. RESULTS: The combined clinical-radiomics model that included 15 radiomic features and 3 clinical features (CA19-9 > 1000 U/ml, vascular invasion and tumor margin), resulting in the area under the curves (AUCs) of 0.974 (95% CI 0.946-1.000) in the derivation cohort, and 0.871-0.882 (95% CI 0.672-0.962) in the internal and external validation cohorts, respectively, which are higher than the AJCC 8th TNM staging system (AUCs: 0.686-0.717, p all < 0.05). Especially, the sensitivity of this machine learning model could reach 94.6% on average for all the cohorts. CONCLUSIONS: This AI-driven combined radiomics model may provide as a useful tool to preoperatively predict ER and improve therapeutic management of ICC patients.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Inteligencia Artificial , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/cirugía , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/cirugía , Neoplasias de los Conductos Biliares/patología
8.
Nat Prod Res ; 37(13): 2144-2150, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35142588

RESUMEN

A new δ-valerolactone compound, named 8-hydroxy invictolide 2 (1), a new natural product 4-hydroxy-3,5-dimethyl-6-(pentan-2-yl) tetrahydro-2H-pyran-2-one (2) together with four known compounds cyclo (L-Pro-L-Tyr) (3), cyclo (D-Pro-L-Tyr) (4), acetyltryptophan methyl ester (5), 2-aminobenzoic acid (6) were isolated from marine Streptomyces sp. YIM 13591. Their structures were elucidated by NMR spectroscopic data, HRESIMS and specific rotation, and the absolute configurations of the stereo centre in lactone ring 1 and 2 were further confirmed by electronic circular dichroism (ECD) calculation. The antimicrobial effects of these compounds were evaluated by the paper diffusion method.


Asunto(s)
Streptomyces , Streptomyces/química , Estructura Molecular , Pironas , Espectroscopía de Resonancia Magnética
9.
Nat Prod Res ; : 1-6, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36323318

RESUMEN

Colletotrin A (1), a new 1,4-benzoxazine derivative, and eight known compounds, including two alkaloids (2-3), one acylamide (4), one benzaldehyde (5), and four sterols (6-9) were obtained from endophytic fungus Colletotrichum gloeosporioides B-142, which was isolated from Dracaena cochinchinensis. Among them, 1,2,3,4-tetrahydroquinoline-4,8-diol (2) was reported for the first time as natural product. The structure of compound 1 was elucidated with help of spectroscopic data including IR, UV, electronic circular dichroism (ECD) calculation, HRESIMS, 1D and 2D NMR (COSY, HSQC and HMBC). The antimicrobial activities were evaluated by disc diffusion method.

10.
Nature ; 609(7928): 709-717, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36131037

RESUMEN

Additive manufacturing methods1-4 using static and mobile robots are being developed for both on-site construction5-8 and off-site prefabrication9,10. Here we introduce a method of additive manufacturing, referred to as aerial additive manufacturing (Aerial-AM), that utilizes a team of aerial robots inspired by natural builders11 such as wasps who use collective building methods12,13. We present a scalable multi-robot three-dimensional (3D) printing and path-planning framework that enables robot tasks and population size to be adapted to variations in print geometry throughout a building mission. The multi-robot manufacturing framework allows for autonomous three-dimensional printing under human supervision, real-time assessment of printed geometry and robot behavioural adaptation. To validate autonomous Aerial-AM based on the framework, we develop BuilDrones for depositing materials during flight and ScanDrones for measuring the print quality, and integrate a generic real-time model-predictive-control scheme with the Aerial-AM robots. In addition, we integrate a dynamically self-aligning delta manipulator with the BuilDrone to further improve the manufacturing accuracy to five millimetres for printing geometry with precise trajectory requirements, and develop four cementitious-polymeric composite mixtures suitable for continuous material deposition. We demonstrate proof-of-concept prints including a cylinder 2.05 metres high consisting of 72 layers of a rapid-curing insulation foam material and a cylinder 0.18 metres high consisting of 28 layers of structural pseudoplastic cementitious material, a light-trail virtual print of a dome-like geometry, and multi-robot simulations. Aerial-AM allows manufacturing in-flight and offers future possibilities for building in unbounded, at-height or hard-to-access locations.

11.
Cancer Sci ; 113(11): 3766-3775, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35968603

RESUMEN

SHARPIN is a tumor-associated gene involved in the growth and proliferation of many tumor types. A function of SHARPIN in cholangiocarcinoma (CCA) is so far unclear. Here, we studied the role and function of SHARPIN in CCA and revealed its relevant molecular mechanism. The expression of SHARPIN was analyzed in cholangiocarcinoma tissues from patients using immunohistochemistry, quantitative PCR, and western blot analysis. Expression of SHARPIN was suppressed/overexpressed by siRNA silencing or lentiviral overexpression vector, and the effect on cell proliferation was determined by the CCK-8 assay and flow cytometry. Accumulation of reactive oxygen species was measured with MitoTracker, and JC-1 staining showed mitochondrial fission/fusion and mitochondrial membrane potential changes as a result of the silencing or overexpression. The ferroptosis marker solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and the antioxidant enzymes superoxide dismutase 1 (SOD-1) and SOD-2 were analyzed by western blot. The results showed that SHARPIN expression was increased in CCA tissue, and this was involved in cell proliferation. SHARPIN silencing resulted in accumulated reactive oxygen species, reduced mitochondrial fission, and a reduced mitochondrial membrane potential. Silencing of SHARPIN inhibited the ubiquitination and degradation of p53, and downregulated levels of SLC7A11, GPX4, SOD-1, and SOD-2, all of which contributed to excessive oxidative stress that leads to ferroptosis. Overexpression of SHARPIN would reverse the above process. The collected data suggest that in CCA, SHARPIN-mediated cell ferroptosis via the p53/SLC7A11/GPX4 signaling pathway is inhibited. Targeting SHARPIN might be a promising approach for the treatment of CCA.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Ferroptosis , Humanos , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Colangiocarcinoma/patología , Proliferación Celular/genética , Transducción de Señal , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/metabolismo , Sistema de Transporte de Aminoácidos y+/metabolismo , Ubiquitinas/metabolismo
12.
Sci Rep ; 12(1): 12684, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35879319

RESUMEN

Optical fiber bending, deformation or shape sensing are important measurement technologies and have been widely deployed in various applications including healthcare, structural monitoring and robotics. However, existing optical fiber bending sensors require complex sensor structures and interrogation systems. Here, inspired by the recent renewed interest in information-rich multimode optical fibers, we show that the multimode fiber (MMF) output speckles contain the three-dimensional (3D) geometric shape information of the MMF itself. We demonstrate proof-of-concept 3D multi-point deformation sensing via a single multimode fiber by using k-nearest neighbor (KNN) machine learning algorithm, and achieve a classification accuracy close to 100%. Our results show that a single MMF based deformation sensor is excellent in terms of system simplicity, resolution and sensitivity, and can be a promising candidate in deformation monitoring or shape-sensing applications.

13.
J Basic Microbiol ; 62(10): 1254-1273, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35852180

RESUMEN

Cordyceps sensu lato is a complex fungus-larva symbiote, and its distribution is affected by the geography, climate, soil environment, and cohabitating microorganisms. However, despite the fact Cordyceps militaris and Ophiocordyceps highlandensis are different species, they coexist in the Pinus armandi forest of Dashao in Songming County, Yunnan, China. We explored the microbial compositions and soil metabolism inhabited by C. militaris and O. highlandensis using high-throughput sequencing and nontargeted metabonomics. The results indicated that the bacterial and fungal compositions in the soil microhabitat communities of C. militaris, O. highlandensis, and null Cordyceps group were similar. However, the community compositions in the fruiting bodies of C. militaris and O. highlandensis were different. The dominant phylum Ascomycota and dominant genus Cordyceps were detected in the fruiting body of C. militaris. Except for Ascomycota, the dominant phylum Chytridiomycota and dominant genera Ophiocordyceps, Unclassified_k__Hypocreales, Circinotrichum, Cladosporium, and Unclassified_k__chytridiomycetesg were detected in the fruiting body of O. highlandensis. The plant probiotic bacteria Phyllobacterium was detected in the fruiting body of C. militaris. The growth-promoting bacteria Pseudomonas was detected in the fruiting body of O. highlandensis. Soil metabolism analysis revealed that pathways associated with amino acid metabolism was significantly enriched in O. highlandensis. Correlation analysis of bacterial diversity and soil metabolites revealed that the relative abundances of bacterial operational taxonomic units and the relative contents of metabolites were consistent. Our results provide insights into the microbial diversity and soil metabolism of naturally coexisting C. militaris and O. highlandensis.


Asunto(s)
Cordyceps , Hypocreales , Microbiota , Aminoácidos/metabolismo , China , Cordyceps/química , Cordyceps/genética , Cordyceps/metabolismo , Cuerpos Fructíferos de los Hongos , Hypocreales/genética , Suelo
14.
Soft Matter ; 17(28): 6697-6706, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34132322

RESUMEN

Soft robots are able to generate large and compliant deformation in an unconstructed environment, but their operation capability is limited by low stiffness. Thus, developing the function of variable stiffness while preserving its compliance is a challenging issue. This study proposes a new variable stiffness artificial muscle, as a complementary component for soft robots, using the principle of fringe electric field adhesion. Taking inspiration from the mechanism of multi-layer structures in biological muscles, the artificial muscle is composed of patterned conductive layers and interlayers and is 3D printable by direct ink writing (DIW). To further demonstrate the application, a vibration absorber by stacking this artificial muscle is proposed, whose natural frequency is tunable by the varying stiffness. The advantages of the fringe electric field-enabled variable stiffness (FEVS) artificial muscles include lightweight and irrelevance of the stiffness to the thickness of the interlayer, which can be beneficial to soft robots to achieve variable stiffness and semi-active vibration attenuation without extra weighting load.


Asunto(s)
Robótica , Vibración , Electricidad , Músculos
15.
Oncol Lett ; 20(3): 2579-2586, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32782575

RESUMEN

Shank-associated RH domain interactor (SHARPIN) is a component of the linear ubiquitin chain activation complex, which is essential for p53 signaling and inflammation. Previous studies have demonstrated that SHARPIN functions in tumor cell survival, growth, invasion and tumorigenesis. These functions include the regulation of p53 proteins via poly-ubiquitination, interaction with a type II protein arginine methyltransferase 5 in melanoma cells, modulating ras-associated protein-1 through p38 and c-Jun N-terminal kinases/c-Jun signaling, and mediating phosphoinositide 3-kinase/AKT signaling via phosphatase and tensin homologue deleted on chromosome 10. Hence, SHARPIN not only participates in the inflammatory response but also serves a critical role in tumor cells. The present review summarizes the biological functions of the absence or presence of SHARPIN with regard to activating the canonical NF-κB signaling pathway and the effects on p53 and other signaling pathways for the modulation of tumorigenesis. Therefore, this review provides insight into the underlying role and mechanisms of SHARPIN in tumorigenesis, as well as its potential application in cancer therapy.

16.
J Cell Mol Med ; 22(7): 3679-3690, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29722127

RESUMEN

The cell surface antigen CD90 has recently been established as a promising marker for liver cancer stem cells. This study aimed to investigate potential implications of SHH/Gli signalling in CD90+ liver cancer stem cells. Correlation of the expression of SHH signalling components and CD90 in liver cancer cells and clinical tissues, as well as in enriched CD90+ liver cancer stem cells and the TCGA database, were analysed by quantitative RT-PCR, Western blotting and flow cytometry. Functional analysis was conducted by siRNA-mediated CD90, Gli1 and Gli3 gene knockdown, SHH treatment and application of the JAK2 inhibitor AZD1480 and IL6 neutralizing antibody in CD90+ liver cancer stem cells, followed by cell proliferation, migration, sphere formation and tumorigenicity assays. CD90 expression exhibited a high positive correlation with Gli1 and Gli3 in multiple liver cancer cell lines and human cancerous liver tissues, both of which showed a significant increase in liver cancer. Analysis of TCGA data revealed an association of CD90, Gli1 and Gli3 with a short overall survival and positive correlation between CD90 expression and Gli3 expression level. The stem cell potentials of CD90+ 97L liver cancer cells were greatly impaired by Gli1/3 knockdown with siRNA but enhanced by SHH treatment. Application of the JAK2 inhibitor AZD1480 and IL6 neutralizing antibody showed the CD90 and SHH/Gli-regulated liver cancer stem cell functions were mediated by the IL6/JAK2/STAT3 pathway. The stem cell properties of CD90+ liver cancer cells are regulated by the downstream SHH/Gli and IL6/JAK2/STAT3 signalling pathways.


Asunto(s)
Neoplasias Hepáticas/patología , Células Madre Neoplásicas/patología , Proteínas del Tejido Nervioso/metabolismo , Antígenos Thy-1/metabolismo , Proteína con Dedos de Zinc GLI1/metabolismo , Proteína Gli3 con Dedos de Zinc/metabolismo , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/metabolismo , Humanos , Interleucina-6/metabolismo , Janus Quinasa 2/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidad , Masculino , Células Madre Neoplásicas/metabolismo , Proteínas del Tejido Nervioso/genética , Factor de Transcripción STAT3/metabolismo , Antígenos Thy-1/genética , Proteína con Dedos de Zinc GLI1/genética , Proteína Gli3 con Dedos de Zinc/genética
17.
Int J Mol Med ; 41(2): 946-954, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29251325

RESUMEN

Cluster of differentiation (CD)90 (Thy­1) was proposed as a marker for the liver cancer stem cells that are responsible for tumorigenic activity, however its involvement in the progression of hepatocellular carcinoma (HCC) remains unknown. The aim of the present study was to determine the effect of CD90 on the biological functions of HCC and to investigate the associated circular RNA (circRNA) involved in this process. The analysis of the in vitro data demonstrated that CD90+ cells isolated from SK­Hep­1 cells exhibited increased viability, migration and invasive abilities compared with CD90­ cells. In addition, circRNA expression profiles in CD90+ and CD90­ cells were screened using a microarray assay and hsa_circ_0067531 and hsa_circ_0057096 were identified to be expressed at significantly different levels. It was additionally demonstrated that the expression of hsa_circ_0067531 in HCC tissues was significantly decreased compared with normal adjacent tissues. Overall, the results of the present study suggested that CD90 may be used as a potential biomarker for HCC. Furthermore, it was demonstrated that hsa_circ_0067531 may affect the biological functions of CD90+ HCC cells and may be a promising candidate to aid in the diagnosis and therapy of HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Movimiento Celular/fisiología , Neoplasias Hepáticas/metabolismo , Antígenos Thy-1/metabolismo , Adulto , Anciano , Western Blotting , Carcinoma Hepatocelular/inmunología , Movimiento Celular/genética , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Femenino , Citometría de Flujo , Humanos , Neoplasias Hepáticas/inmunología , Masculino , Persona de Mediana Edad , Antígenos Thy-1/fisiología
18.
Am J Transl Res ; 9(5): 2106-2118, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28559964

RESUMEN

Glutamate dehydrogenase (GDH) produces a precursor to glutathione, an important molecule in maintaining cellular redox balance and the cancerous characteristics of tumor cells through intracellular signaling pathways. However, the underlying molecular mechanisms linking glutamate dehydrogenase and extrahepatic cholangiocarcinoma have not been elucidated yet. Herein, we examined GDH expression levels and evaluated its potential correlations with prognosis. Meanwhile, the therapeutic value of GDH targeting the Smad pathways in extrahepatic cholangiocarcinoma was explored. Immunohistochemical studies revealed that GDH expression level was correlated to CD34 expression, cellular differentiation, the presence or absence of capsular and vascular invasion, lymph node metastasis, neural invasion and patient age. Kaplan-Meier survival analysis and COX proportional hazards models demonstrated that the prognosis was closely associated with GDH expression, CD34 positivity, nerve infiltration and cell differentiation. GDH silencing significantly reduced the proliferation, migratory potential and invasive capability. We also demonstrated that GDH promoted cell proliferation and metastasis potentially through Smad-mediated induction of TGF-ß signaling pathway. Therefore, GDH may be an important prognostic indicator and may provide a new target for novel treatments of extrahepatic cholangiocarcinoma.

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