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1.
Eur J Surg Oncol ; 49(12): 107118, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37844471

RESUMO

BACKGROUND: Early recurrence (ER) is a significant concern following curative resection of advanced colorectal cancer (CRC) and is linked to poor long-term survival. Reliable prediction of ER is challenging, necessitating the development of a novel radiomics-based nomogram for CRC patients. METHODS: We enrolled 405 patients, with 298 in the training set and 107 in the external test set. Radiomic features were extracted from preoperative venous-phase computed tomography (CT) images. A radiomics signature was created using univariate logistic regression analyses and the least absolute shrinkage and selection operator algorithm. Clinical factors were integrated into the analyses to develop a comprehensive predictive tool in a multivariate logistic regression model, resulting in a radiomics nomogram. Subsequently, the calibration, discrimination, and clinical usefulness of the nomogram were evaluated. RESULTS: The radiomics signature, consisting of four selected CT features, was significantly associated with ER in both the training and test datasets (P < 0.05). Independent predictors of ER included TNM stage, carcinoembryonic antigen level and differentiation grade were identified. The radiomics nomogram, incorporating all these predictors, exhibited good predictive ability in both the training set with an area under the curve (AUC) of 0.82 (95 % confidence interval (CI), 0.74-0.90) and the test set with an AUC of 0.85 (95 % CI, 0.72-0.99), surpassing the performance of any single candidate factor alone. Furthermore, additional analysis demonstrated that the nomogram was clinically useful. CONCLUSIONS: We have developed a radiomics-based nomogram that effectively predicts early recurrence in CRC patients, enhancing the potential for timely intervention and improved outcomes.


Assuntos
Neoplasias Colorretais , Nomogramas , Humanos , Tomografia Computadorizada por Raios X/métodos , Veias , Algoritmos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/cirurgia
2.
J Am Chem Soc ; 145(16): 9198-9206, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37125453

RESUMO

Aryl-ketone derivatives have been acknowledged as promising organic photocatalysts for photosynthesis. However, they are limited by their photostability and have been less explored for photoinduced electron transfer (PET) applications. Herein we demonstrate a novel strategy to cover the shortage of aryl-ketone photocatalysts and control the photoreactivity by implanting symmetric aryl ketones into the conjugated covalent organic frameworks (COFs). To prove the concept, three comparative materials with the same topology and varied electronic structures were built, adopting truxenone knot and functionalized terephthalaldehyde linkers. Spectroscopic investigation and excited carrier dynamics analysis disclosed improvements in the photostability and electronic transfer efficiency as well as the structure-performance relationships toward N-aryl tetrahydroisoquinoline oxidation. This system provides a robust rule of thumb for designing new-generation aryl-ketone photocatalysts.

3.
Sci Rep ; 11(1): 18063, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34508146

RESUMO

Current research on DNA storage usually focuses on the improvement of storage density by developing effective encoding and decoding schemes while lacking the consideration on the uncertainty in ultra-long-term data storage and retention. Consequently, the current DNA storage systems are often not self-contained, implying that they have to resort to external tools for the restoration of the stored DNA data. This may result in high risks in data loss since the required tools might not be available due to the high uncertainty in far future. To address this issue, we propose in this paper a self-contained DNA storage system that can bring self-explanatory to its stored data without relying on any external tool. To this end, we design a specific DNA file format whereby a separate storage scheme is developed to reduce the data redundancy while an effective indexing is designed for random read operations to the stored data file. We verified through experimental data that the proposed self-contained and self-explanatory method can not only get rid of the reliance on external tools for data restoration but also minimise the data redundancy brought about when the amount of data to be stored reaches a certain scale.


Assuntos
DNA/genética , Bases de Dados Genéticas , Armazenamento e Recuperação da Informação/métodos , Algoritmos , DNA/química , Humanos , Modelos Teóricos , Pesquisa
4.
Nanomedicine (Lond) ; 16(19): 1657-1671, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34261362

RESUMO

Aim: To evaluate the gastroprotective effects of Nelumbinis Rhizomatis Nodus carbon dots (NRN-CDs) on ethanol-induced gastric ulcers in rats. Materials & methods: NRN-CDs synthesized and characterized by transmission electron microscopy, ultraviolet, fluorescence and Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, x-ray diffraction and zeta potential analyzer. Their gastroprotective effects toward ethanol-induced gastric ulcers were evaluated in male Sprague-Dawley rats. Results: NRN-CDs showed an average diameter of 2.33 ± 0.42 nm and a lattice spacing of 0.29 nm. Pretreatment with NRN-CDs significantly decreased the ulcer index and attenuated the severity of gastric mucosal damage, indicating that NRN-CDs exerted potent gastric protective effect. Moreover, the gastroprotection effect was related to the regulation of oxidative stress and inflammatory factors. Conclusion: NRN-CDs could be developed as a potential drug for the treatment of gastric ulcers.


Assuntos
Medicamentos de Ervas Chinesas , Úlcera Gástrica , Animais , Carbono , Etanol/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico
5.
Int J Nanomedicine ; 16: 2461-2475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814910

RESUMO

AIM: To explore the effects of Radix Sophorae Flavescentis carbonisata-based carbon dots (RSFC-CDs) on an ethanol-induced acute gastric ulcer rat model. METHODS: The structure, optical properties, functional groups and elemental composition of RSFC-CDs synthesized by one-step pyrolysis were characterized. The gastric protective effects of RSFC-CDs were evaluated and confirmed by applying a rat model of ethanol-induced acute gastric ulcers. The underlying mechanisms were investigated through the nuclear factor-kappa B (NF-κB) signalling pathway and oxidative stress. RESULTS: RSFC-CDs with a diameter ranging from 2-3 nm mainly showed gastric protective effects by reducing the levels of NF-κB, tumour necrosis factor-α (TNF-α), interleukin (IL)-6, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione (GSH), malondialdehyde (MDA) and inducible nitric oxide synthase (iNOS) to inhibit ethanol-induced inflammation and oxidative stress. CONCLUSION: RSFC-CDs have anti-inflammatory and anti-oxidative effects, making them promising for application in ethanol-induced gastric injury.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Carbono/química , Medicamentos de Ervas Chinesas/uso terapêutico , Substâncias Protetoras/uso terapêutico , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Doença Aguda , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Etanol/efeitos adversos , Interleucina-6/metabolismo , Masculino , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Úlcera Gástrica/patologia , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
Int J Nanomedicine ; 15: 9049-9059, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33235451

RESUMO

INTRODUCTION: The charcoal processed product of Paeoniae Radix Alba (PRA), PRA Carbonisata (PRAC), has long been used for its hepatoprotective effects. However, the material basis and mechanism of action of PRAC remain unclear. AIM: To explore the hepatoprotective effects of Paeoniae Radix Alba Carbonisata-derived carbon dots (PRAC-CDs). METHODS: PRAC-CDs were characterized using transmission electron microscopy, high-resolution transmission electron microscopy, ultraviolet, fluorescence, Fourier transform infrared and X-ray photoelectron spectroscopy, X-ray diffraction, and high-performance liquid chromatography. The hepatoprotective effect of PRAC-CDs was evaluated and confirmed using the classic carbon tetrachloride acute liver injury model. RESULTS: PRAC-CDs averaged 1.0-2.4 nm in size and exhibited a quantum yield of 5.34% at a maximum excitation wavelength of 320 nm and emission at 411 nm. PRAC-CDs can reduce the ALT and AST levels of mice with carbon tetrachloride-induced acute liver injury and have a mitigating effect on the rise in TBA and TBIL. More interestingly, PRAC-CDs can significantly reduce MDA and increase SOD levels, demonstrating that PRAC-CDs can improve the body's ability to scavenge oxygen free radicals and inhibit free radical-induced liver cell lipid peroxidation, thereby preventing liver cell damage. CONCLUSION: These results demonstrate the remarkable hepatoprotective effects of PRAC-CDs against carbon tetrachloride-induced acute liver injury, which provide new insights into potential biomedical and healthcare applications of CDs.


Assuntos
Carbono/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Fígado/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Pontos Quânticos/química , Animais , Ductos Biliares/efeitos dos fármacos , Tetracloreto de Carbono , Morte Celular/efeitos dos fármacos , Carvão Vegetal , Cromatografia Líquida de Alta Pressão , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Espectroscopia Fotoeletrônica , Pontos Quânticos/ultraestrutura , Células RAW 264.7 , Superóxido Dismutase/metabolismo , Transaminases/metabolismo
7.
Int J Nanomedicine ; 15: 4139-4149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606669

RESUMO

INTRODUCTION: A correlation is established between the efficacy of Chinese herbal medicine and its charcoal drugs. Lonicerae japonicae Flos (LJF) is commonly used to treat fever, carbuncle, and tumors, among others. LJF Carbonisatas (LJFC) is preferred for detoxifying and relieving dysentery and its related symptoms. However, the mechanisms underlying the effects of LJFC remain unknown. AIM: The aim of this study was to explore the effects of LJFC-derived carbon dots (LJFC-CDs) on lipopolysaccharide (LPS)-induced fever and hypothermia rat models. METHODS: LJFC-CDs were characterized using transmission electron microscopy, high-resolution transmission electron microscopy, Fourier-transform infrared, ultraviolet, fluorescence, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. The anti-inflammatory effects of LJFC-CDs were evaluated and confirmed using rat models of LPS-induced fever or hypothermia. RESULTS: The LJFC-CDs ranged from 1.0 to 10.0 nm in diameter, with a yield of 0.5%. LJFC-CDs alleviated LPS-induced inflammation, as demonstrated by the expression of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 and the recovery of normal body temperature. CONCLUSION: LJFC-CDs may have an anti-inflammatory effect and a potential to alleviate fever and hypothermia caused by inflammation.


Assuntos
Carbono/química , Febre/tratamento farmacológico , Hipotermia/tratamento farmacológico , Lonicera/química , Extratos Vegetais/uso terapêutico , Animais , Temperatura Corporal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , AMP Cíclico/metabolismo , Citocinas/metabolismo , Dinoprostona/metabolismo , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Mediadores da Inflamação/sangue , Lipopolissacarídeos , Masculino , Camundongos , Extratos Vegetais/toxicidade , Células RAW 264.7 , Ratos Sprague-Dawley , Espectrometria de Fluorescência
8.
ACS Synth Biol ; 7(11): 2577-2589, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30274509

RESUMO

To produce chemicals and fuels from renewable resources, various strategies and genetic tools have been developed to redesign pathways and optimize the metabolic flux in microorganisms. However, in most successful cases, the target chemicals are synthesized through a linear pathway, and regular methodologies for the identification of bottlenecks and metabolic flux optimization in multibranched and multilevel regulated pathways, such as the l-methionine biosynthetic pathway, have rarely been reported. In the present study, a systematic analysis strategy was employed to gradually reveal and remove the potential bottlenecks limiting the l-methionine biosynthesis in E. coli. 80 genes in central metabolism and selected amino acids biosynthetic pathways were first repressed or upregulated to probe their effects on l-methionine accumulation. The l-methionine biosynthetic pathway was then modularized and iteratively genetic modifications were performed to uncover the multiple layers of limitations and stepwise improve the l-methionine titer. The metabolomics data further revealed a more evenly distributed metabolic flux in l-methionine biosynthesis pathway of the optimal strain and provided valuable suggestions for further optimization. The optimal strain produced 16.86 g/L of l-methionine in 48 h by fed-batch fermentation. This work is the first to our knowledge to systematically elucidate the molecular fundamentals of multilevel regulation of l-methionine biosynthesis. It also demonstrated that the systematic analysis strategy can boost our ability to identify the potential bottlenecks and optimize the metabolic flux in multibranched and multilevel regulated pathways for the production of corresponding chemicals.


Assuntos
Escherichia coli/metabolismo , Metionina/biossíntese , Sistemas CRISPR-Cas/genética , Carbono/metabolismo , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Edição de Genes , Regulação Bacteriana da Expressão Gênica , Espectrometria de Massas , Engenharia Metabólica/métodos , Metionina/análise , Plasmídeos/genética , Plasmídeos/metabolismo , Regiões Promotoras Genéticas
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