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1.
2.
Quantum Front ; 3(1): 12, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855163

RESUMO

FeSe is one of the most enigmatic superconductors. Among the family of iron-based compounds, it has the simplest chemical makeup and structure, and yet it displays superconducting transition temperature ( T c ) spanning 0 to 15 K for thin films, while it is typically 8 K for single crystals. This large variation of T c within one family underscores a key challenge associated with understanding superconductivity in iron chalcogenides. Here, using a dual-beam pulsed laser deposition (PLD) approach, we have fabricated a unique lattice-constant gradient thin film of FeSe which has revealed a clear relationship between the atomic structure and the superconducting transition temperature for the first time. The dual-beam PLD that generates laser fluence gradient inside the plasma plume has resulted in a continuous variation in distribution of edge dislocations within a single film, and a precise correlation between the lattice constant and T c has been observed here, namely, T c ∝ c - c 0 , where c is the c-axis lattice constant (and c 0 is a constant). This explicit relation in conjunction with a theoretical investigation indicates that it is the shifting of the d xy orbital of Fe which plays a governing role in the interplay between nematicity and superconductivity in FeSe. Supplementary Information: The online version contains supplementary material available at 10.1007/s44214-024-00058-0.

3.
Cancer Biol Ther ; 25(1): 2306676, 2024 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-38289287

RESUMO

Fusobacterium nucleatum, an anaerobic Gram-negative bacterium primarily residing in the oral cavity, has garnered significant attention for its emerging role in cancer progression and prognosis. While extensive research has revealed mechanistic links between Fusobacterium nucleatum and colorectal cancer, a comprehensive review spanning its presence and metastatic implications in cancers beyond colorectal origin is conspicuously absent. This paper broadens our perspective from colorectal cancer to various malignancies associated with Fusobacterium nucleatum, including oral, pancreatic, esophageal, breast, and gastric cancers. Our central focus is to unravel the mechanisms governing Fusobacterium nucleatum colonization, initiation, and promotion of metastasis across diverse cancer types. Additionally, we explore Fusobacterium nucleatum's adverse impacts on cancer therapies, particularly within the domains of immunotherapy and chemotherapy. Furthermore, this paper underscores the clinical research significance of Fusobacterium nucleatum as a potential tumor biomarker and therapeutic target, offering a novel outlook on its applicability in cancer detection and prognostic assessment.


Assuntos
Neoplasias Colorretais , Neoplasias Gástricas , Humanos , Fusobacterium nucleatum , Carcinogênese , Transformação Celular Neoplásica
4.
Environ Sci Technol ; 57(41): 15432-15442, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37802498

RESUMO

Herein, we propose a label-free chemiresistive sensor for the highly sensitive and selective detection of microcystin (MC)-LR in water samples. The sensor uses a layer-by-layer (LBL) assembled conductive film consisting of Ti3C2Tx nanosheets as the sensing channel. It is further modified by using an aptamer for the specific recognition of MC-LR. The response signal is based on the change in resistance of the conductive channel upon binding of MC-LR with the aptamer. Our novel strategy is the first concept proposed for immobilizing the aptamer containing -SH on the channel surface through a Ti-S bond under weakly alkaline condition. The resulting sensor is highly sensitive and stable for the detection of MC-LR, with a detection limit of 0.18 ng L-1 and a wide linear range from 1 to 104 ng L-1. We used the sensor to continuously monitor MC-LR released by cultivated Microcystis aeruginosa, showing a strong relationship between MC-LR and cell density. Furthermore, the sensor was successfully used to measure MC-LR in freshwater lakes with moderate algal blooms, and the results agreed well with those obtained by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The present study provides a reliable method for highly sensitive and selective detection of MC-LR in environmental waters.


Assuntos
Microcistinas , Espectrometria de Massas em Tandem , Microcistinas/análise , Microcistinas/química , Cromatografia Líquida , Titânio , Lagos/análise , Água/química
5.
Cancers (Basel) ; 15(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36980779

RESUMO

Cancer has been the first killer that threatens people's lives and health. Despite recent improvements in cancer treatment, metastasis continues to be the main reason for death from cancer. The functions of microbiome in cancer metastasis have been studied recently, and it is proved that microbiome can influence tumor metastasis, as well as positive or negative responses to therapy. Here, we summarize the mechanisms of microorganisms affecting cancer metastasis, which include epithelial-mesenchymal transition (EMT), immunity, fluid shear stress (FSS), and matrix metalloproteinases (MMPs). This review will not only give a further understanding of relationship between microbiome and cancer metastasis, but also provide a new perspective for the microbiome's application in cancer metastasis prevention, early detection, and treatment.

6.
Oncotarget ; 8(30): 49574-49591, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28484095

RESUMO

Cancer as a large group of complex diseases is believed to result from the interactions of numerous genetic and environmental factors but may develop in people without any known genetic or environmental risks, suggesting the existence of other powerful factors to influence the carcinogenesis process. Much attention has been focused recently on particular members of the intestinal microbiota for their potential roles in promoting carcinogenesis. Here we report the identification and characterization of intestinal bacteria that exhibited potent anti-malignancy activities on a broad range of solid cancers and leukemia. We collected fecal specimens from healthy individuals of different age groups (preschool children and university students), inspected their effects on cancer cells, and obtained bacteria with potent anti-malignancy activities. The bacteria mostly belonged to Actinobacteria but also included lineages of other phyla such as Proteobacteria and Firmicutes. In animal cancer models, sterile culture supernatant from the bacteria highly effectively inhibited tumor growth. Remarkably, intra-tumor administration of the bacterial products prevented metastasis and even cleared cancer cells at remote locations from the tumor site. This work demonstrates the prevalent existence of potent malignancy-killers in the human intestinal microbiota, which may routinely clear malignant cells from the body before they form cancers.


Assuntos
Microbioma Gastrointestinal , Neoplasias/etiologia , Adolescente , Adulto , Animais , Bactérias/classificação , Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Sobrevivência Celular , Criança , Pré-Escolar , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Células HeLa , Humanos , Masculino , Metagenoma , Metagenômica/métodos , Camundongos , Neoplasias/patologia , Filogenia , RNA Ribossômico 16S/genética , Adulto Jovem
7.
Am J Chin Med ; 44(8): 1543-1558, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27852123

RESUMO

Acanthopanax senticosus (previously classified as Eleutherococcus senticosus), commonly known as Ciwujia or Siberian Ginseng, is a traditional Chinese medicine (TCM), widely used for its high medicinal value, such as antifatigue, anti-inflammation, antistress, anti-ulcer and cardiovascular functions, in China, Korea, Japan and Russia. In the past decades, researchers worldwide have conducted systematic investigations on this herb, from chemistry to pharmacology, and a large number of chemical components have been characterized for their significant pharmacological effects. However, reports about the anticancer effects of this plant had been rare until recently, when considerable pharmacological experiments both in vitro and in vivo were conducted to study the anticancer effects of this herb. A. senticosus has been found to have inhibitory effects on malignant tumors, such as those in the lung and liver, suggesting that A. senticosus has potential to be developed as an effective anticancer drug. This paper reviews recent findings on the pharmacological properties of A. senticosus, with a focus on its anticancer effects.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Cumarínicos/farmacologia , Cumarínicos/uso terapêutico , Dioxóis/farmacologia , Dioxóis/uso terapêutico , Eleutherococcus/química , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Lignanas/farmacologia , Lignanas/uso terapêutico , Fenilpropionatos/farmacologia , Fenilpropionatos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes , Cumarínicos/isolamento & purificação , Dioxóis/isolamento & purificação , Relação Dose-Resposta a Droga , Glucosídeos/isolamento & purificação , Humanos , Fatores Imunológicos/uso terapêutico , Lignanas/isolamento & purificação , Medicina Tradicional Chinesa , Camundongos , Fenilpropionatos/isolamento & purificação , Fitoterapia , Ratos
8.
Carbohydr Polym ; 119: 101-9, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25563949

RESUMO

Rhizoma alismatis (the rhizome of Alisma orientalis) polysaccharides (RAP) have been reported to have a variety of important biological activities. However, effective extraction of RAP has been an unsolved issue. In this study, we used an ultrasound method for high yield extraction of RAP and optimized the conditions using the response surface methodology (RSM). Following multiple regression analyses of the experimental results, we applied the 3-D response surface and the contour plots to determine the optimal conditions, which were found to be ultrasound treatment at 76.1°C for 75.2 min, and water to material ratio at 30.1 ml/g. Under such conditions, the yield was 6.90% which was much higher than traditional hot water extraction yield (3.41%). The fractionated RAPs following stepwise ethanol precipitation showed strong antioxidant activities. The results indicated that ultrasound extraction was a very effective method for the extraction of RAP and the polysaccharides could be explored as a potential antioxidant agent for use in medicine or functional food.


Assuntos
Alisma/química , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Polissacarídeos/isolamento & purificação , Ultrassom/métodos , Análise de Variância , Animais , Compostos de Bifenilo/química , Eritrócitos/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Hemólise/efeitos dos fármacos , Temperatura Alta , Masculino , Peso Molecular , Picratos/química , Polissacarídeos/farmacologia , Ratos Wistar , Reprodutibilidade dos Testes , Espectrofotometria Infravermelho , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Água/farmacologia
9.
Bioorg Med Chem Lett ; 24(16): 4053-7, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24986658

RESUMO

Three kinds of chitooligosaccharides (COS) with different degrees of deacetylation were prepared and named MD90, MD70 and MD50, respectively. Antioxidation, antiglycation and nitric oxide (NO) promotion in erythrocyte of these samples were investigated. The results showed that COS, especially MD90 had obviously inhibitory effects on oxidation and glycation. In addition, MD90 displayed stronger effect on increasing endogenous NO content than both MD70 and MD50, whose degrees of deacetylation were lower. The results indicated that amino group in COS has a certain effect on the activities of COS. As COS have a conformed activity to treat diabetes, the results of this study may be meaningful for further understanding the mechanism of the action.


Assuntos
Antioxidantes/farmacologia , Quitosana/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Óxido Nítrico/biossíntese , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Acetilação , Antioxidantes/síntese química , Antioxidantes/química , Quitosana/síntese química , Quitosana/química , Relação Dose-Resposta a Droga , Glicosilação/efeitos dos fármacos , Humanos , Oligossacarídeos/síntese química , Oligossacarídeos/química , Oxirredução/efeitos dos fármacos , Relação Estrutura-Atividade
10.
Int J Biol Macromol ; 59: 290-4, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23628583

RESUMO

In this study, effects of several experimental parameters, including ultrasonic time, ratio of water to material, extraction temperature and ultrasonic power on the extraction yield of polysaccharides from Acanthopanax senticosus stem (ASS) were investigated by single factor experiment and an orthogonal test design (L9(3)(4)) was used to optimize the ultrasound extraction conditions. The polysaccharides from Acanthopanax senticosus stem (ASSP) and fruit (ASFP) were further fractionated by stepwise ethanol precipitation and the anti-oxidation activities of those fractions were evaluated by hydroxyl, superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Under the optimal conditions (ultrasonic time 75min, ratio of water to material 50ml/g, extraction temperature 80°C and ultrasonic power 100W), the yield was 10.9mg/g. All fractions of ASP possessed considerable antioxidant activity. The results indicated that the ultrasound extraction was a very useful method for the extraction of ASP and the polysaccharides could be explored as a potential antioxidant agent for use in medicine or functional food.


Assuntos
Eleutherococcus/química , Frutas/química , Caules de Planta/química , Polissacarídeos/química , Sonicação/normas , Compostos de Bifenilo/antagonistas & inibidores , Análise Fatorial , Radical Hidroxila/antagonistas & inibidores , Picratos/antagonistas & inibidores , Polissacarídeos/isolamento & purificação , Superóxidos/antagonistas & inibidores , Temperatura , Água
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