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1.
Polymers (Basel) ; 16(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38891451

RESUMO

This work aimed to investigate the effects of aging on the microstructures and rheological properties of modified asphalt with a GO/SBS composite, since the styrene-butadiene-styrene block copolymer is potentially compatible with graphene oxide (GO). The GO/SBS composites, which were used as a kind of modifier, were prepared via the solution-blending method. GO/SBS composites with varying GO contents were employed to prepare the GO/SBS-compound-modified asphalt (GO/SBS-MA). Then, the GO/SBS-MA underwent PAV (pressure aging vessel) or UV (ultraviolet) aging tests to simulate different aging circumstances. The microstructures of the asphalt binders were studied using FTIR (Fourier-transform infrared spectroscopy) and AFM (atomic force microscope) tests. Moreover, DSR (dynamic shear rheometer) and BBR (bending beam rheometer) experiments were carried out to investigate the rheological properties of the GO/SBS-MA. The results showed that the addition of GO improved the high-temperature stability of the asphalt binder while slightly impairing its performance at low temperatures. GO restrained the formation of carbonyl and sulfoxide groups as well as the breakdown of C=C bonds in the polybutadiene (PB) segment, promoting the anti-aging performance of GO/SBS-MA. Furthermore, the interactions between the GO/SBS and the asphalt binder resulted in the formation of needle-like aggregates, enhancing the stability of the asphalt binder. The asphalt binders with a higher content of graphene oxide (GO) exhibited not only a better high-temperature performance, but also a better aging resistance. It was concluded that the macroscopic properties and microstructures were significantly affected by GO, and a moderate increase in the amount of GO could contribute to a better aging resistance for GO/SBS-MA.

2.
PLoS One ; 18(5): e0280971, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37195935

RESUMO

Breast cancer ranks first among female cancers and has become a major public health problem in the current society. More studies indicated that these cancers are related to the change in the gut microbiome that can cause metabolic and immune system disorders in the body. However, there are few studies on the changes in gut microbiome caused by the onset of breast cancer, and the relationship between breast cancer and gut microbiome needs to be further clarified. In this study, we inoculated 4T1 breast cancer cells to induce breast cancer tumorigenesis in mice and collected their feces samples at different stages during this process. These intestinal florae were analyzed using 16S rRNA gene amplicon sequencing, and the results showed that at the phylum level, the ratio of Firmicutes/Bacteroidetes decreased with the development of the tumor; at the family level, the intestinal microbiome had obvious variations of Lachnospiraceae, Bacteroidaceae, Erysipelotrichaceae, etc. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and COG annotation demonstrated that decreased abundance of cancer-related signaling pathways. This study elucidated the relationship between breast cancer and intestinal microbiome, and the research results can be used as an important biomarker for the diagnosis of breast cancer.


Assuntos
Microbioma Gastrointestinal , Animais , Feminino , Camundongos , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Firmicutes/genética , Bacteroidetes/genética , Carcinogênese , Fezes
3.
Materials (Basel) ; 15(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36556678

RESUMO

Coal gasification slag is an inevitable by-product of the coal gasification process. This paper explored the feasibility of using activators (calcium hydroxide, sodium hydroxide, calcium sulfate, sodium sulfate) to promote the pozzolanic activity of milled coal gasification coarse slags (MCS), and analyzed the effect of alkali and sulfate activators on the hydration characteristic of cement-based materials containing MCS. Coal gasification slags with ignition lossses more than 15% were removed and the remaining slags were considered as cementitious material after milling. Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and hydration heat tests were employed to analyze the hydration mechanism of the samples. Besides, the compressive strength values of cement mortars with MCS and activators were evaluated. The results showed that calcium hydroxide was conductive to the formation of hydration products and its crystallization could contribute to the strength improvement of the sample. Calcium sulfate mainly participated in the hydration process of cement to form ettringite (AFt) phases. Sodium hydroxide could accelerate the dissolution of active mineral phases of MCS, resulting in the pozzolanic activity being enhanced. Moreover, sodium sulfate could not only increase the formation of AFt phases, but also improved the alkalinity in sample to facilitate the production of gels. Among them, a better promotion effect could be obtained from the combined application of calcium hydroxide and sodium sulfate. In addition, the compressive strength values of cement mortars containing MCS tended to increase when activators were used. The sample activated by calcium hydroxide and sodium sulfate exhibited the highest strength, increasing by 18.55% at 28 days compared with the sample without an activator.

4.
Biomed Res Int ; 2020: 1537873, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32149079

RESUMO

In this study, a yeast strain with an outstanding NH3-N degradation ability was isolated from the sediment of a black-odor water channel in Guangdong Province, China. Based on phenotypic and phylogenetic analysis, this strain was identified as Pichia kudriavzevii GW1. The optimum conditions for NH3-N degradation by the GW1 strain were as follows: 0.3% inoculum concentration, 1.5 L/min aeration, pH 7, and a temperature of 35°C. Under optimized conditions, the GW1 strain degraded 95.5% of the NH3-N. The strain was then added to simulated black-odor water under optimal degradation conditions to investigate changes to the bacterial community over time. 16S rRNA sequencing of samples collected on days 0, 7, 14, and 21 showed that, in the presence of the GW1 strain, the relative abundances of the phyla Proteobacteria, Bacteroidetes, Chloroflexi, and Firmicutes increased in the black-odor water. In addition, the relative abundance of Propionivibrio, a known NH3-N degrading genus, increased. This study will facilitate the use of microbiological methods to repair black-odor water.


Assuntos
Amônia/metabolismo , Pichia , Esgotos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Análise da Demanda Biológica de Oxigênio , China , Nitrogênio/metabolismo , Odorantes , Pichia/classificação , Pichia/genética , Pichia/isolamento & purificação , Pichia/metabolismo , Esgotos/química , Temperatura , Purificação da Água
5.
Fish Shellfish Immunol ; 58: 96-102, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27633674

RESUMO

Antimicrobial peptides (AMPs) are ubiquitously found in living organisms and are an important component in innate immune response. Tachyplesin I is a potent antimicrobial peptide isolated from the hemocytes of the horseshoe crab, Tachypleus tridentatus. Previous studies have shown that the 17-residue peptide exhibits a wide spectrum of antimicrobial activity against Gram-negative and Gram-positive bacteria, fungi, protozoa, and viruses. However, the efficiencies and defense mechanisms of the Tachyplesin I against fish viruses are still unknown. In this study, Tachyplesin I showed a key role in inhibiting the infection and replication of two kinds of newly emerging marine fish viruses, an enveloped DNA virus of Singapore grouper iridovirus (SGIV), and a non-enveloped RNA virus of viral nervous necrosis virus (RGNNV). Synthetic peptides of Tachyplesin I incubated with virus or cells before infection reduced the viral infectivity. Synthetic peptides of Tachyplesin I drastically decreased SGIV and RGNNV titers and viral gene expression. Grouper spleen (GS) and brain (GB) cells over-expressing Tachyplesin I (GS/pcDNA3.1-flag-Tac I and GB/pcDNA3.1-flag-Tac I) support the inhibition of viral infection. Tachyplesin I activated type I IFN and Interferon-sensitive response element (ISRE) in vitro. The promoter activity of IFN-ß and ISRE were significantly up-regulated in cells transfected with pcDNA3.1-flag-Tac I after infection with SGIV and VNNV. These results suggest that Tachyplesin I is importantly involved in host immune responses to invasion of viral pathogens.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Artrópodes/metabolismo , Proteínas de Ligação a DNA/metabolismo , Caranguejos Ferradura/imunologia , Caranguejos Ferradura/virologia , Nodaviridae/fisiologia , Peptídeos Cíclicos/metabolismo , Ranavirus/fisiologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Proteínas de Artrópodes/genética , Proteínas de Ligação a DNA/genética , Caranguejos Ferradura/genética , Interferon Tipo I/genética , Interferon Tipo I/metabolismo , Peptídeos Cíclicos/genética
6.
Mol Cancer ; 14: 3, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25608466

RESUMO

BACKGROUND: Recent studies have demonstrated that long non-coding RNAs (lncRNAs) were present in the blood of cancer patients and have shown great potential as powerful and non-invasive tumor markers. However, little is known about the value of lncRNAs in the diagnosis of esophageal squamous cell carcinoma (ESCC). We hypothesized that ESCC-related lncRNAs might be released into the circulation during tumor initiation and could be utilized to detect and monitor ESCC. METHODS: Ten lncRNAs (HOTAIR, AFAP1-AS1, POU3F3, HNF1A-AS1, 91H, PlncRNA1, SPRY4-IT1, ENST00000435885.1, XLOC_013104 and ENST00000547963.1) which previously found to be differently expressed in esophageal cancer were selected as candidate targets for subsequent circulating lncRNA assay. A four-stage exploratory study was conducted to test the hypothesis: (1) optimization of detected method to accurately and reproducibly measure ESCC-related lncRNAs in plasma and serum; (2) evaluation of the stability of circulating lncRNAs in human plasma or serum; (3) exploration the origin of ESCC-related lncRNAs in vitro and in vivo; (4) evaluation the diagnostic power of circulating lncRNAs for ESCC. RESULTS: ESCC-related lncRNAs were detectable and stable in plasma of cancer patients, and derived largely from ESCC tumor cells. Furthermore, plasma levels of POU3F3, HNF1A-AS1 and SPRY4-IT1 were significantly higher in ESCC patients compared with normal controls. By receiver operating characteristic curve (ROC) analysis, among the three lncRNAs investigated, plasma POU3F3 provided the highest diagnostic performance for detection of ESCC (the area under the ROC curve (AUC), 0.842; p < 0.001; sensitivity, 72.8%; specificity, 89.4%). Moreover, use of POU3F3 and SCCA in combination could provide a more effective diagnosis performance (AUC, 0.926, p < 0.001, sensitivity, 85.7%; specificity, 81.4%). Most importantly, this combination was effective to detect ESCC at an early stage (80.8%). CONCLUSIONS: Plasma POU3F3 could serve as a potential biomarker for diagnosis of ESCC, and the combination of POU3F3 and SCCA was more efficient for ESCC detection, in particular for early tumor screening.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/diagnóstico , RNA Longo não Codificante/sangue , Animais , Antígenos de Neoplasias/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estadiamento de Neoplasias , Estabilidade de RNA , Curva ROC , Reprodutibilidade dos Testes , Serpinas/metabolismo
7.
Tumour Biol ; 35(8): 7743-54, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24810925

RESUMO

LncRNA SPRY4-IT1 has been shown to promote the progression of melanoma. However, the role of lncRNA SPRY4-IT1 in human esophageal squamous cell carcinoma (ESCC) remains unclear. The purpose of this study is to investigate the clinical significance and biological functions of SPRY4-IT1 in ESCC. The expression levels of lncRNA SPRY4-IT in 92 ESCC patients and 8 ESCC cell lines were evaluated by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). The prognostic significance was evaluated using Kaplan-Meier and Cox regression analyses. Small interfering RNA (siRNA) was used to suppress SPRY4-IT1 expression in ESCC cell lines. Both in vitro and in vivo assays were performed to further explore its role in tumor progression. SPRY4-IT1 levels were significantly higher in ESCC tissues and cells than in corresponding adjacent noncancerous tissues and nontumorigenic esophageal epithelial cells, and the ESCC patients with higher SPRY4-IT1 expression had an advanced clinical stage and poorer prognosis than those with lower SPRY4-IT1 expression. The multivariate analysis revealed that SPRY4-IT1 expression level is an independent prognostic factor in ESCC patients. In vitro assays demonstrated that knockdown of SPRY4-IT1 reduced cell proliferation, invasiveness, and migration. In vivo assays demonstrated that knockdown of SPRY4-IT1 decreases cell growth. SPRY4-IT1 is a novel molecule involved in ESCC progression, which may provide a potential prognostic biomarker and a potential target for therapeutic intervention.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/fisiologia , Idoso , Animais , Carcinoma de Células Escamosas/mortalidade , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , RNA Longo não Codificante/genética , Regulação para Cima
8.
Dig Dis Sci ; 59(3): 591-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24337686

RESUMO

BACKGROUND: Recent studies revealed that long noncoding RNAs (lncRNAs) play critical regulatory roles in cancer biology. PlncRNA-1 is one of lncRNAs that is associated with cell apoptosis and proliferation of prostate cancer. AIM: This study aimed to assess the potential role of PlncRNA-1 in the pathogenesis of esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression level of PlncRNA-1 in 73 pairs of ESCC and their matched normal tissues. The correlation of PlncRNA-1 with clinicopathological features and clinical stages was also analyzed. Cancer cell proliferation and apoptosis were assessed following knock-down of PlncRNA-1 by MTT, colony formation assay, and flow cytometry. RESULTS: The expression of PlncRNA-1 was significantly higher in human ESCC compared with the adjacent noncancerous tissues (69.8 %, p < 0.05), and the high level of PlncRNA-1 expression was significantly correlated with advanced clinical stage (p < 0.01) and lymph node metastasis (p < 0.05). Furthermore, knockdown of PlncRNA-1 reduced cell proliferation and increased the apoptosis in vitro. CONCLUSIONS: PlncRNA-1 plays an important role in ESCC cell proliferation. Overexpression of PlncRNA-1 is correlated with advanced tumor stage and lymph node metastasis, and may serve as a potential prognostic marker and therapeutic target for ESCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/metabolismo , Regulação para Cima , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Citometria de Fluxo , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Mol Carcinog ; 52(11): 908-15, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24151120

RESUMO

Recent studies of the individual functionalities of long non-coding RNAs (lncRNAs) in the development and progression of cancer have suggested that HOX transcript antisense RNA (HOTAIR) is capable of reprogramming chromatin organization and promoting cancer cell metastasis. In order to ascertain the expression pattern of the lncRNA HOTAIR and assess its biological role in the development and progression of esophageal squamous cell carcinoma (ESCC), HOTAIR expression in ESCC tissues and adjacent noncancerous tissues were collected from 78 patients and measured by real-time reverse transcription-polymerase chain reaction (RT-PCR). HOTAIR correlation with clinicopathological features and prognosis was also analyzed. Suppression of HOTAIR using siRNA treatment was performed in order to explore its role in tumor progression. Notably elevated HOTAIR expression levels were observed in cancerous tissues compared to adjacent noncancerous tissues (96%, P < 0.01), showing a high correlation with cancer metastasis (P < 0.01), elevated TNM (2009) stage classification (P < 0.01), and lowered overall survival rates (P = 0.003). Multivariate analysis revealed that HOTAIR expression (P = 0.003) is also an independent prognostic factor for comparison of TNM stage (P = 0.024) and lymph node metastasis (P = 0.010). Furthermore, in vitro assays of the ESCC cell line KYSE30 demonstrated that knockdown of HOTAIR reduced cell invasiveness and migration while increasing the response of cells to apoptosis. Thus, HOTAIR is a novel molecule involved in both ESCC progression and prognosis. Full elucidation of HOTAIR functionality relevant to ESCC may open avenues for the use of lncRNAs in identification of novel drug targets and therapies for ESCC and other prevalent cancers.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , RNA Longo não Codificante/genética , Regulação para Cima , Apoptose , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Esôfago/metabolismo , Esôfago/patologia , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Prognóstico
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(4): 902-6, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20842868

RESUMO

A new method for constructing the model of vascular trees was proposed in this paper. By use of this method, the arterial trees in good agreement with the actual structure could be grown. In this process, all vessels in the vascular tree were divided into two groups: the conveying vessels, and the delivering branches. And different branches could be built by different ways. Firstly, the distributing rules of conveying vessels were ascertained by use of measurement data, and then the conveying vessels were constructed in accordance to the statistical rule and optimization criterion. Lastly, delivering branches were modeled by constrained constructive optimization (CCO) on the conveying vessel-trees which had already been generated. In order to compare the CCO method and stepwise method proposed here, two 3D arterial trees of human tongue were grown with their vascular tree having a special structure. Based on the corrosion casts of real arterial tree of human tongue, the data about the two trees constructed by different methods were compared and analyzed, including the averaged segment diameters at respective levels, the distribution and the diameters of the branches of first level at respective directions. The results show that the vascular tree built by stepwise method is more similar to the true arterial of human tongue when compared against the tree built by CCO method.


Assuntos
Algoritmos , Artérias/anatomia & histologia , Artérias/fisiologia , Simulação por Computador , Modelos Cardiovasculares , Pressão Sanguínea/fisiologia , Hemodinâmica/fisiologia , Humanos , Imageamento Tridimensional , Resistência Vascular/fisiologia
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 27(6): 1220-3, 1232, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21374967

RESUMO

The parameters which can influence heat transfer of tongue were analyzed in order to reveal the reason why the tongue temperature fields of people with different diseases are distinct. Firstly, the research parameters were determined by experiment results, including the reference humidity of tongue surface, metabolic heat of tongue tissue, the entrance position of root vessel, the diameter of root vessel, the blood flow rate, and the bifurcation exponent of vascular tree. Then the effect of each parameter on the value and the distributing rule of tongue temperature field was analyzed by using a mathematic model of lingual temperature field. Results show that all these parameters have effects on the temperature value of tongue. The reference humidity of tongue surface, the metabolic heat of tongue tissue and the entrance position of root vessel are distinct influences on the distributing rule of tongue temperature.


Assuntos
Temperatura Corporal/fisiologia , Modelos Teóricos , Língua/fisiologia , Humanos , Umidade , Fluxo Sanguíneo Regional , Condutividade Térmica , Língua/irrigação sanguínea
12.
Mar Biotechnol (NY) ; 11(1): 109-17, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18670810

RESUMO

To produce tachyplesin, an antimicrobial peptide, by a stable and efficient gene engineering approach, cDNAs containing single tachyplesin gene sequence (tac)(1) and tandem repeat of tachyplesin gene sequence (tac2) were respectively developed by annealing two synthesized complementary single-stranded DNAs and constructed into pSBPTQ shuttle vector under the control of the SacB.p.s promoter. The vectors containing the target gene sequence were then transformed into Bacillus subtilis WB800, respectively. Both expression of tac and tac2 were induced by 2% sucrose. The fermentation supernatant was purified by regenerated cellulose membrane tubing (MWCO 2000) and the secreted TAC(2) and TAC2 were about 5 and 10 mg/l of supernatant, respectively. The antimicrobial activities of TAC and TAC2 were measured by the size of bacteriostatic circle of the fermentation supernatants against Escherichia coli K88. Ultrastructural alteration of E. coli K88 and Salmonella typhimurium was observed under scanning electron microscope and transmission electron microscopy. The results showed that in comparison with TAC, TAC2 was expressed at a higher level and also indicating strong antimicrobial activity both in vitro and in vivo.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/farmacologia , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Regulação Bacteriana da Expressão Gênica , Camundongos , Peptídeos Cíclicos/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/ultraestrutura
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