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1.
Front Nutr ; 9: 1060783, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36545470

RESUMEN

Catechins are a cluster of polyphenolic bioactive components in green tea. Anticarcinogenic effects of tea catechins have been reported since the 1980s, but it has been controversial. The present paper reviews the advances in studies on the anticarcinogenic activities of tea and catechins, including epidemiological evidence and anticarcinogenic mechanism. Tea catechins showed antagonistic effects on many cancers, such as gynecological cancers, digestive tract cancers, incident glioma, liver and gallbladder cancers, lung cancer, etc. The mechanism underlying the anticarcinogenic effects of catechins involves in inhibiting the proliferation and growth of cancer cells, scavenging free radicals, suppressing metastasis of cancer cells, improving immunity, interacting with other anticancer drugs, and regulating signaling pathways. The inconsistent results and their causes are also discussed in this paper.

2.
Front Chem ; 10: 984652, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072706

RESUMEN

High strength polyvinyl alcohol (PVA)/soy protein isolate (SPI) composite hydrogels (EPSG) were constructed by the introduction of PVA into SPI through the crosslinking with epichlorohydrin (ECH) and a freezing-thawing process. The EPSG hydrogels were characterized by scanning electron microscopy, FTIR, X-ray diffraction and compressive test. The results revealed that chemical crosslinking interactions occurred for SPI and PVA during the fabrication process. The composite hydrogels exhibited a homogenous porous structure, indicating certain miscibility between PVA and SPI. The introduction of PVA increased the compressive strength of SPI hydrogels greatly, which could reach as high as 5.38 MPa with the water content ratio of 89.5%. Moreover, the water uptake ratio of completely dried SPI hydrogel (namely xerogel) decreased gradually from 327.4% to 148.1% with the incorporation of PVA, showing a better potential as implants. The cytocompatibility and hemocompatibility of the EPSG hydrogels were evaluated by a series of in vitro experiments. The results showed that the EPSG hydrogels had no cytotoxicity (cell viability values were above 86.7%), good biocompatibility and hemocompatibility, showing potential applications as a direct blood contact material in the field of tissue engineering.

3.
Foods ; 12(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36613339

RESUMEN

Excessive intake of high-caffeine tea will induce health-related risk. Therefore, breeding and cultivating tea cultivars with less caffeine is a feasible way to control daily caffeine intake. Cocoa tea (Camellia ptilophylla Chang) is a wild tea plant which grows leaves with little or no caffeine. However, the vegetative propagation of cocoa tea plants is difficult due to challenges with rooting. Whether natural seeds collected from wild cocoa tea plants can be used to produce less-caffeinated tea remains unknown, because research on the separation of traits among the seed progeny population is lacking. The present study was set to investigate the variation of caffeine and other chemical compositions in seed-propagated plant individuals using colorimetric and HPLC methods. It shows that there were great differences in chemical composition among the seed-propagated population of wild cocoa tea plants, among which some individuals possessed caffeine contents as high as those of normal cultivated tea cultivars (C. sinensis), suggesting that the naturally seed-propagated cocoa tea seedlings are not suitable for directly cultivating leaf materials to produce low-caffeine tea. Therefore, the cocoa tea plants used for harvesting seeds for growing low-caffeine tea plants should be isolated in order to prevent their hybridization with normal cultivated C. sinensis plants. Interestingly, the leaves of cocoa tea seedlings contained high levels of gallocatechin gallate (GCG) and would be a good source of leaf materials for extracting more stable antioxidant, because GCG is a more stable antioxidant than epigallocatechin gallate (EGCG), the dominant component of catechins in normal cultivated tea cultivars. Some plant individuals which contained low levels of caffeine along with high levels of amino acids and medium levels of catechins, are considered to be promising for further screening of less-caffeinated green tea cultivars.

4.
Materials (Basel) ; 15(1)2021 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-35009352

RESUMEN

Zirconia ceramics are widely used in many fields because of their excellent physical and mechanical properties. However, there are some challenges to machine zirconia ceramics with high processing efficiency. In order to optimize parameters for milling zirconia ceramics by polycrystalline diamond tool, finite element method was used to simulate machining process based on Johnson-Cook constitutive model. The effects of spindle speed, feed rate, radial and axial cutting depth on cutting force, tool flank wear and material removal rate were investigated. The results of the simulation experiment were analyzed and optimized by the response surface method. The optimal parameter combination was obtained when the spindle speed, feed rate, radial and axial cutting depth were 8000 r/min, 90.65 mm/min, 0.10 mm and 1.37 mm, respectively. Under these conditions, the cutting force was 234.81 N, the tool flank wear was 33.40 µm when the milling length was 60 mm and the material removal rate was 44.65 mm3/min.

5.
Nucleic Acids Res ; 48(20): 11762-11772, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33068413

RESUMEN

Mfd-dependent transcription termination plays an important role in transcription-coupled DNA repair, transcription-replication conflict resolution, and antimicrobial resistance development. Despite extensive studies, the molecular mechanism of Mfd-dependent transcription termination in bacteria remains unclear, with several long-standing puzzles. How Mfd is activated by stalled RNA polymerase (RNAP) and how activated Mfd translocates along the DNA are unknown. Here, we report the single-particle cryo-electron microscopy structures of T. thermophilus Mfd-RNAP complex with and without ATPγS. The structures reveal that Mfd undergoes profound conformational changes upon activation, contacts the RNAP ß1 domain and its clamp, and pries open the RNAP clamp. These structures provide a foundation for future studies aimed at dissecting the precise mechanism of Mfd-dependent transcription termination and pave the way for rational drug design targeting Mfd for the purpose of tackling the antimicrobial resistance crisis.


Asunto(s)
Proteínas Bacterianas/química , Factores de Transcripción/química , Terminación de la Transcripción Genética , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/química , Microscopía por Crioelectrón , ADN Bacteriano/química , ARN Polimerasas Dirigidas por ADN/química , Modelos Moleculares , Thermus thermophilus
6.
Waste Manag ; 109: 222-230, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32416564

RESUMEN

The metal in the waste printed circuit boards (WPCBs) is an excellent secondary metal resource. WPCBs were ground to dissociate, and impurities in the dissociated product were removed by gradient flotation to recover valuable metals in this study. The effects of crushing methods on size composition and dissociation state of the crushed products were studied. Then the gradient flotation experiment was designed to verify the natural floatability of ground materials. Grinding test shows that impact crushing has greater grinding fineness (-0.074 mm) than shear crushing, which is 42.14% and 26.18% respectively with 5 min grinding. The flotation test results illustrate that the natural floatability of impurities increases with the grinding fineness, that is, the yield of floats increases without flotation reagents. For impact crushing and shear crushing, the floats yields are 38.48% and 31.75% respectively, accompanied by 70.53% and 65.46% impurity removal for ground materials with 5 min grinding. Subsequently, 21.61% and 26.35% of impurities can be further removed with the aid of collector. Finally, the recovery of Cu in concentrate reaches 67.84% and 65.75%, respectively. FT-IR proves that the excellent floatability of particles is caused by the significant hydrophobic group. Mechanical grinding has been proved to have double effects of improving dissociation and natural floatability.


Asunto(s)
Residuos Electrónicos , Interacciones Hidrofóbicas e Hidrofílicas , Metales , Reciclaje , Espectroscopía Infrarroja por Transformada de Fourier
7.
Life Sci ; 202: 124-130, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29605445

RESUMEN

AIMS: This study aimed to assess plasma lncRNA microRNA-31 hist gene (MIR31HG) as a novel diagnostic and therapeutic biomarker for esophageal squamous cell carcinoma (ESCC) and to investigate its role in ESCC. MAIN METHODS: The expression of MIR31HG, Furin and MMP1 was examined via quantitative real-time polymerase chain reaction. MIR31HG expression between plasma and ESCC tissues was compared using Pearson correlation analysis; furthermore, the association between Furin/MMP1 levels and MIR31HG levels in ESCC tissues was analyzed. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of plasma MIR31HG. A WST-1 assay was performed to assess cell proliferation. The migratability and invasiveness of cells was determined via Transwell assays. KEY FINDINGS: MIR31HG was significantly upregulated in ESCC tissues and plasma (P < 0.01). A significant positive association was obtained between plasma and tissue MIR31HG expression in ESCC (r = 0.78, P < 0.01). Furthermore, MIR31HG displayed high diagnostic sensitivity and specificity for predicting ESCC occurance. Furthermore, knockdown of MIR31HG suppressed the capacity for proliferation, migration, and invasion of ESCC cells (P < 0.01). In addition, silencing of MIR31HG inhibited the expression of Furin and MMP1 in EC9706 and EC1 and the level of Furin/MMP1 in ESCC tissues displayed a significant positive correlation with MIR31HG (P < 0.01). SIGNIFICANCE: MIR31HG can be used as a novel potential diagnostic biomarker and a potential therapeutic target for ESCC.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , ARN Largo no Codificante/sangre , ARN Largo no Codificante/genética , Biomarcadores de Tumor/sangre , Movimiento Celular/genética , Proliferación Celular , Carcinoma de Células Escamosas de Esófago , Furina/genética , Silenciador del Gen , Humanos , Metaloproteinasa 1 de la Matriz/genética , Invasividad Neoplásica/genética , Valor Predictivo de las Pruebas , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Regulación hacia Arriba/genética
8.
Dis Markers ; 2017: 3437679, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28386155

RESUMEN

[This corrects the article DOI: 10.1155/2016/1857067.].

9.
Medicine (Baltimore) ; 95(12): e2983, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27015172

RESUMEN

A total knee arthroplasty (TKA) has always been associated with moderate-to-severe pain. A systematic review of randomized controlled trials (RCTs) and non-RCTs was performed to evaluate the efficacy and safety of pain control of adductor canal block (ACB) and femoral nerve block (FNB) after TKA.Relevant literatures about the ACB and FNB after TKA for reducing pain were searched from Medline (1996-January, 2015), Embase (1980-January, 2015), PubMed (1980-January, 2015), Web of Science (1980-January, 2015), and The Cochrane Central Register of Controlled Trials. High-quality RCTs and non-RCTs were picked to evaluate the visual analogue scale (VAS) and other outcome. This systematic review and meta-analysis were performed according to the PRISMA statement criteria. The software RevMan 5.30 was used for the meta-analysis.Eight literatures fitted into the inclusion criteria. There were no significant differences in VAS score with rest or mobilization at 4, 24, and 48 h between ACB group and FNB group. There were also no significant differences in the strength of quadriceps and adductor, the length of hospital stay, and complications of vomiting and nausea.Present meta-analysis indicated that ACB shows no superiority than FNB group. Both of them can reduce the pain score after TKA. As referred to which method to adopt, it is determined by the preference of the surgeons and anesthesiologists.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Bloqueo Nervioso/métodos , Dolor Postoperatorio/terapia , Humanos , Tiempo de Internación , Fuerza Muscular , Dimensión del Dolor , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Dis Markers ; 2016: 1857067, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26989293

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is a common human malignancy with poor survival, which was usually diagnosed at an advanced stage. MicroRNAs (miRNAs), a class of single stranded noncoding RNAs with only 17-25 ribonucleotides, were demonstrated to play an important role in lots of cancers. In the recent years, increasing evidence revealed that circulating miRNAs exhibited great potential in the diagnosis of various types of cancers. The present study was designed to evaluate the diagnostic value of plasma miRNA-216a/b for ESCC. Our results showed that the expression level of plasma miRNA-216a/b was significantly lower in ESCC patients compared with that of healthy controls. The receiver operating characteristic (ROC) curve analysis yielded an area under the ROC curve (AUC) value of 0.877 [95% CI (confidence interval): 0.818-0.922] for miRNA-216a and 0.756 (95% CI: 0.685-0.819) for miRNA-216b. Clinical data indicated that plasma miRNA-216a/b were inversely correlated with lymph node metastasis and TNM stage. Additionally, the plasma miRNA-216b expression level was significantly upregulated in postoperative samples compared to preoperative samples. Our study, for the first time, demonstrated that plasma miRNA-216a/b might serve as potential biomarkers for the diagnosis of ESCC and dysregulation of miRNA-216a/b might be involved in the progression of ESCC.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , MicroARNs/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/patología , Regulación hacia Abajo , Detección Precoz del Cáncer , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Femenino , Predisposición Genética a la Enfermedad , Humanos , Metástasis Linfática , Masculino , Valor Predictivo de las Pruebas , Curva ROC
11.
Cancer Biomark ; 16(2): 265-73, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26756617

RESUMEN

BACKGROUND: Increasing evidence demonstrated that circulating miRNAs could serve as meaningfully non-invasive and reliable biomarkers for the detection of various cancers. OBJECTIVE: To investigate the expression level of plasma miRNA-718 in esophageal squamous cell carcinoma (ESCC) patients and its diagnostic value. METHODS: Quantitative real time polymerase chain reaction (qRT-PCR) method was performed to examine the expression levels of plasma miRNA-718 in 120 consecutive ESCC patients and 51 healthy controls. The difference of plasma miRNA-718 expression level between the paired pre- and postoperative patients was compared. The correlation between plasma miRNA-718 expression levels and clinicopathological characteristics was further analyzed and the receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic power of plasma miRNA-718 for ESCC. RESULTS: Plasma miRNA-718 expression level of ESCC patients was significantly lower than that of healthy controls. Compared with preoperative patients, the plasma miRNA-718 expression level of postoperative patients was significantly upregulated. Plasma miRNA-718 expression level was inversely correlated with the lymph node metastasis and TNM stage. The ROC curve analysis showed that plasma miRNA-718 yielded AUCs of 0.715, 0.689 and 0.620 for the detection of ESCC patients, early patients with Tis-T1 or early patients with TNM 0-I, respectively. CONCLUSION: Plasma miRNA-718 is downregulated in ESCC patients and might serve as a potential diagnostic marker for ESCC.


Asunto(s)
Biomarcadores de Tumor , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , MicroARNs/sangre , MicroARNs/genética , Adulto , Anciano , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirugía , Estudios de Casos y Controles , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Curva ROC
12.
Mol Cell Biochem ; 394(1-2): 137-44, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24833470

RESUMEN

MicroRNA (miRNAs) is demonstrated to be present in the blood of humans and has been increasingly suggested as a novel biomarker for various pathological processes in the heart, including myocardial infarction, myocardial remodeling and progression to heart failure. In this study, we aim to evaluate the diagnostic and prognostic value of circulating miR-328 and miR-134 in patients with acute myocardial infarction (AMI). Circulating levels of miR-328 and miR-134 were detected by quantitative real-time PCR in plasma samples from 359 AMI patients and 30 healthy volunteers. Concentrations of high-sensitivity cardiac troponin T (hs-cTnT) were measured using electrochemiluminescence-based methods. MiRNAs were assessed for discrimination of a clinical diagnosis of AMI and for association with primary clinical endpoint defined as a composite of cardiogenic death and development of heart failure within 6 months after infarction. Results showed that levels of plasma miR-328 and miR-134 were significantly higher in AMI patients than in healthy controls. Receiver operating characteristic curve analyses showed significant diagnostic value of miR-328 and miR-134 for AMI. However, neither of them was superior to hs-cTnT for the diagnosis. Additionally, increased miRNA levels were strongly associated with increased risk of mortality or heart failure within 6 months for miR-328 (OR 7.35, 95 % confidence interval 1.07-17.83, P < 0.001) and miR-134 (OR 2.28, 95 % confidence interval 1.03-11.32 P < 0.001). In conclusion, circulating miR-328 and miR-134 could be potential indicators for AMI, and the miRNA levels are associated with increased risk of mortality or development of heart failure.


Asunto(s)
MicroARNs/sangre , Infarto del Miocardio/diagnóstico , Adulto , Anciano , Área Bajo la Curva , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Progresión de la Enfermedad , Diagnóstico Precoz , Femenino , Marcadores Genéticos , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/mortalidad , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/sangre , Infarto del Miocardio/complicaciones , Infarto del Miocardio/genética , Infarto del Miocardio/mortalidad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Factores de Riesgo , Factores de Tiempo , Troponina T/sangre , Regulación hacia Arriba
13.
Int J Mol Sci ; 15(4): 5774-88, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24714087

RESUMEN

Left ventricular remodeling after acute myocardial infarction (AMI) is associated with adverse prognosis. It is becoming increasingly clear that circulating miRNAs could be promising biomarkers for various pathological processes in the heart, including myocardial infarction, myocardial remodeling and progression to heart failure. In the present study, a total of 359 consecutive patients were recruited. Plasma samples were collected on admission. Echocardiographic studies were performed during the admission and at six months follow-up after AMI. Remodeling was defined as an at least 10% increase from baseline in the left ventricular end-diastolic volume. Plasma miRNA levels were assessed for association with six months mortality or development of heart failure. Results showed that levels of plasma miR-208b and miR-34a were significantly higher in patients with remodeling than those without. Increased miRNA levels were strongly associated with increased risk of mortality or heart failure within six months for miR-208b (OR 17.91, 95% confidence interval=2.07-98.81, p=0.003), miR-34a (OR 4.18, 95% confidence interval=1.36-12.83, p=0.012) and combination of the two miRNAs (OR 18.73, 95% confidence interval=1.96-101.23, p=0.000). The two miRNA panels reclassified a significant proportion of patients with a net reclassification improvement of 11.7% (p=0.025) and an integrated discrimination improvement of 7.7% (p=0.002). These results demonstrated that circulating miR-208b and miR-34a could be useful biomarkers for predicting left ventricular remodeling after AMI, and the miRNA levels are associated with increased risk of mortality or heart failure.


Asunto(s)
Biomarcadores/sangre , MicroARNs/sangre , Infarto del Miocardio/genética , Remodelación Ventricular/genética , Femenino , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/mortalidad , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/mortalidad , Pronóstico
14.
Bioelectrochemistry ; 74(1): 164-9, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18722826

RESUMEN

Studies on the interaction of DNA with vitamin B(6) were carried out with a DNA-modified electrode by electrochemistry and Ultraviolet-visible spectroscopy. The results showed that there exists the supra-molecule interaction between base groups on DNA and vitamin B(6) by forming hydrogen binding, the binding equilibrium constant of the interaction is equal to 115.3 M(-1), the binding ratio of nucleotide to vitamin B(6) is 5:1. Based on the electrochemical and Ultraviolet-visible spectrum studies the interaction mode of DNA with vitamin B(6) was explored.


Asunto(s)
ADN/química , Electroquímica , Vitamina B 6/química , Sitios de Unión , Electrodos , Enlace de Hidrógeno , Espectrofotometría Ultravioleta
15.
Artículo en Chino | MEDLINE | ID: mdl-18051571

RESUMEN

OBJECTIVE: To evaluate the expression and clinical significance of Endostatin, vascular endothelial growth factor (VEGF) and fibroblast growth factor basic-2 (FGF-2) in the laryngeal squamous cell carcinoma (LSCC). METHODS: The expression of Endostatin, VEGF and FGF-2 in 50 specimens of LSCC, 40 specimens of para-carcinoma and 10 specimens of normal laryngeal tissues were examined by Flow cytometry. RESULTS: Compared with para-carcinoma and normal laryngeal tissues, the expression level and positive rate of Endostatin, VEGF, FGF-2 in LSCC were different in statistics (P < 0.05); the expression level and positive rate of endostatin, VEGF, FGF-2 in LSCC are obviously higher than those in para-carcinoma and normal laryngeal tissues. The expression level and positive rate of Endostatin, VEGF, FGF-2 were no difference in statistics between para-carcinoma and normal laryngeal tissues (P > 0.05). The expression level and positive rate of Endostatin, VEGF, FGF-2 in LSCC were associated with lymphoid metastasis and clinical stage, not associated with age, sex and clinical group. CONCLUSIONS: Endostatin, VEGF and FGF-2 play important role in the incidence, development and prognosis of the LSCC.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Endostatinas/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Neoplasias Laríngeas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico
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