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1.
Sci Rep ; 14(1): 11700, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778184

RESUMEN

Jiarong Tibetan is a regional group with distinctive regional characteristics and possess precious traditional village resources. Studying the spatial distribution and influencing factors of traditional villages is of vital significance for the protection and renewal of villages and the revitalization of cultural heritage. Nevertheless, due to the fact that the Jiarong Tibetan inhabited area has not been clearly defined for a long time, there is a lack of holistic discussion on the distribution features and driving mechanisms of traditional villages in this region. In order to fill this research gap, the paper is the first to break away from the existing county administrative divisions to define the study area. Moreover, the analysis is carried out by using the nearest neighbor index, kernel density, GoeDa and Geodetector, etc. for traditional villages at national-level and provincial-level. The results show that the spatial distribution of the traditional villages of Jiarong Tibetan is characterized by typical aggregation, with the core intensive area in Danba County and the sub-core intensive area in the central and northern parts. The results of factor detection show that the spatial distribution pattern of the traditional villages is the consequence of the synergistic effect of multiple factors, and the interaction effect is significantly enhanced. The economic level and climatic conditions play a controlling role, and population, elevation, intangible cultural heritage and rivers also have notable effects. The findings of study can offer scientific guidance and suggestions for the inheritance and development of traditional villages in Jiarong Tibetan settlement area.

2.
Materials (Basel) ; 17(8)2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38673283

RESUMEN

This pilot investigation identifies the influence that changing the process variables of curing pressure, curing temperature, and mix ratio of a polyurethane/agglomerated cork matrix has on the mechanical properties of energy absorption, Young's modulus of elasticity, and spring stiffness in safety helmets intended for micro-transport riders. The results are compared to expanded polystyrene, a material commonly used in micro-transport helmets. Mechanical testing of the various samples found that, over the range tested, curing pressure had no effect on any of the mechanical properties, while increasing amounts of resin caused a stiffer structure, and increasing curing temperature led to increased energy absorption. Consistent with the elastic modulus findings, all polyurethane/agglomerated cork test samples demonstrated higher median levels of spring stiffness, ranging from 7.1% to 61.9% greater than those found for expanded polystyrene. The sample mixed at a 1.5:1 binder/cork ratio and cured at 40 °C displayed the closest spring stiffness to EPS. While the mechanical properties of the eco-friendly polyurethane/agglomerated cork matrix did not match those of expanded polystyrene, the difference in performance found in this study is promising. Further investigation into process variables could characterise this more ecologically based matrix with equivalent energy-absorbing and structural characteristics, making it equivalent to currently used expanded polystyrene and suitable for use in micro-transport helmets.

3.
Polymers (Basel) ; 15(19)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37835991

RESUMEN

Cellulose-based aerogels have been seen as a promising sorbent for oil and organic pollutant cleaning; however, their intrinsic hydrophilicity and difficulty of recycling has hindered their practical application. In this work, a superhydrophobic, magnetic cellulose-based aerogel was fabricated as a highly efficient sorbent for the adsorption of oils and organic solvents. The aerogel was prepared via a simple freeze-drying method, followed by chemical vapor deposition (CVD). The incorporation of Fe3O4 nanoparticles into the aerogel not only makes it responsive to external magnetic field, but also contributes to the better hydrophobicity of the aerogel, in which the water contact angle (WCA) was about 20° higher than the aerogel without loading with Fe3O4 nanoparticles. The adsorption test showed that the resultant aerogel can selectively adsorb a wide range of oils and organic solvents from oil/water mixtures with a high adsorption capacity (up to 113.49 g/g for silicone oil). It can retain about 50% of its adsorption capacity even after 10 adsorption-squeezing cycles, which indicates its outstanding reusability. Moreover, the aerogels can be easily controlled by an external magnet, which is preferred for the adsorption of oily contaminants in harsh environments and enhanced the recyclability of the aerogel. We believe that this study provides a green and convenient approach for the practical fabrication of cellulose-based oil sorbents.

4.
Anal Chim Acta ; 1252: 341052, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-36935140

RESUMEN

Oral health is an essential part of overall health. Matrix metalloproteinase-2 (MMP-2) is a potential biomarker for diseases. The ability to accurately detect MMP-2 in vivo and in vitro is of great importance for the early diagnosis and prognosis, as well as the treatment evaluation, of oral diseases. In this study, cyanine 3 (Cy3) polypeptide containing the specific peptide substrate (PLGVR) of MMP-2 was modified onto SiO2-coated upconversion nanoparticles to fabricate a fluorescence resonance energy transfer (FRET)-based ratiometric fluorescent nanoplatform (UCNPs@SiO2@Cy3-pep). The green upconversion luminescence of UCNPs@SiO2 is quenched by Cy3, while its red upconversion luminescence is undisturbed. After Cy3 is cleaved at the PLGVR peptide by MMP-2, it is detached from the surface of UCNPs@SiO2, resulting in the recovery of green luminescence. Based on this principle, we applied UCNPs@SiO2@Cy3-pep to detect MMP-2 activity in different oral disease samples and models. We found that the level of MMP-2 in saliva of patients with oral cancer was 10 times higher than that of healthy individuals. In addition, the MMP-2 level in patients with periodontitis and severe dental caries also increased to varying degrees compared with that in healthy patients. Finally, in vitro and in vivo imaging experiments revealed that the nanoplatform was effective in monitoring MMP-2 level. Together, the developed nanoplatform can be an ideal tool for medical diagnosis of MMP-2-related diseases.


Asunto(s)
Caries Dental , Enfermedades de la Boca , Nanopartículas , Humanos , Colorantes , Transferencia Resonante de Energía de Fluorescencia/métodos , Luminiscencia , Metaloproteinasa 2 de la Matriz , Péptidos , Dióxido de Silicio , Salud Bucal , Enfermedades de la Boca/diagnóstico
5.
Hematology ; 27(1): 1056-1061, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36112003

RESUMEN

BACKGROUND: The CYP2C19 gene is highly polymorphic, and CYP2C19 is involved in the broad interindividual variability of the clinical efficacy of certain clinical medications, such as clopidogrel. However, data on the CYP2C19 genotype in the Chinese population of the Foshan area of Guangdong Province are scarce. The purpose of this study was to determine CYP2C19 genetic polymorphisms in patients in the Foshan area and to compare the CYP2C19 genotype frequencies in different populations to determine the allele distribution pattern to identify the most appropriate prescription. METHODS: The CYP2C19 gene was detected in 1231 patients on a gene chip platform, and the genotype frequencies of CYP2C19 in Foshan populations from different populations were compared. RESULTS: The frequencies of CYP2C19*1, *2 and *3 in the Foshan population were 63.89%, 30.46% and 5.65%, respectively. For the three metabolic types, the frequency associated with the rapid metabolism type (*1/*1) was 41.51 [95% confidence interval (CI) 40.11 to 42.91%]; that for the intermediate metabolism type (*1/*2, *1/*3) was 44.76% (95% CI 43.34 to 46.18) and that for the slow metabolism type (*2/*2, *2/*3, *3/*3) was 13.73% (95% CI 12.75 to 14.71%). In the Foshan population, the frequencies of the CYP2C19 *2 and *3 alleles were similar to those previously reported for Chinese and other Asian populations. CONCLUSION: Our study is a report on the genetic basis of CYP2C19 polymorphism in the Foshan population. Our results will potentially contribute to the improvement of pharmacotherapy effectiveness by providing personalized medicine for the Foshan population.


Asunto(s)
Clopidogrel , Citocromo P-450 CYP2C19 , Hidrocarburo de Aril Hidroxilasas/genética , Hidrocarburo de Aril Hidroxilasas/metabolismo , China , Clopidogrel/farmacología , Clopidogrel/uso terapéutico , Citocromo P-450 CYP2C19/genética , Frecuencia de los Genes , Humanos , Polimorfismo Genético
6.
MycoKeys ; 83: 181-208, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720643

RESUMEN

Cryphaluspiceae attacks various economically important conifers. Similar to other bark beetles, Cr.piceae plays a role as a vector for an assortment of fungi and nematodes. Previously, several ophiostomatoid fungi were isolated from Cr.piceae in Poland and Japan. In the present study, we explored the diversity of ophiostomatoid fungi associated with Cr.piceae infesting pines in the Shandong Province of China. We isolated ophiostomatoid fungi from both galleries and beetles collected from our study sites. These fungal isolates were identified using both molecular and morphological data. In this study, we recovered 175 isolates of ophiostomatoid fungi representing seven species. Ophiostomaips was the most frequently isolated species. Molecular and morphological data indicated that five ophiostomatoid fungal species recovered were previously undescribed. Thus, we proposed these five novel species as Ceratocystiopsisyantaiensis, C.weihaiensis, Graphilbumtranslucens, Gr.niveum, and Sporothrixvillosa. These new ophiostomatoid fungi add to the increasing number of fungi known from China, and this evidence suggests that numerous novel taxa are awaiting discovery in other forests of China.

7.
BMC Infect Dis ; 19(1): 71, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30658581

RESUMEN

BACKGROUND: To provide a scientific basis for the prevention and treatment of cervical cancer (CC), we investigated the distribution characteristics and genotypes of human papillomavirus (HPV) and the prevalence of multiple HPV infections in women of different ages seeking management for abnormal cytology in Foshan City. METHODS: Screening for the 21 genotypes of HPV was carried out in 9945 females seeking management of abnormal cervical cytology results using rapid flow-through hybridization of nucleic acid molecules. The overall prevalence, genotype distribution and age-specific prevalence were examined. RESULTS: Our results indicate that the prevalence of overall, high-risk, intermediate-risk, and low-risk HPV infections was 13.5%, 12.1%, 1.3%, and 1.9%, respectively. Of the 1346 women who tested positive, 89.5% were positive for a single HPV genotype, and 10.5% were positive for ≥2 genotypes. The most frequently detected HPV genotype was HPV-16 (2.9%), followed by HPV-52 (2.9%), HPV-58 (1.5%), and HPV-CP8304 (1.0%). The highest infection prevalence was found in patients 21-30 years old (271/1670, 16.2%). CONCLUSION: The prevalence of HPV infection in women seeking management for abnormal cytology in Foshan City is highest in the younger population (21-30 years old). Similar to most previous surveys, HPV-58 and HPV-52 infections are as common as HPV-16 infection.


Asunto(s)
Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Genotipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Persona de Mediana Edad , Hibridación de Ácido Nucleico , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/epidemiología , Prevalencia , Adulto Joven
8.
RSC Adv ; 9(3): 1476-1486, 2019 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-35518021

RESUMEN

B, N dual-doped sisal-based activated carbon (BN-SAC) with a multiscale porous structure for high-rate supercapacitor electrode was prepared through a novel and facile strategy. With the inherent cellular channels serving as primary macropores, secondary mesopores and micropores are generated on the fiber surface and tracheid walls through low-pressure rapid carbonization of (NH4)2B4O7-containing sisal fibers and successive KOH activation. In addition to introducing B, N atoms into the BN-SAC, the additive also facilitates the formation of mesopores due to the rapid gas evaporation during its decomposition, leading to significantly increased specific surface area (2017 m2 g-1) and mesoporosity (68.6%). As a result, the BN-SAC-3 shows highly enhanced electrochemical performance including a high specific capacitance of 304 F g-1, excellent rate capability (with 72.6% retention at 60 A g-1) and superior cycling stability (4.6% capacitance loss after 3000 cycles). After assembling the BN-SAC-3 into symmetric supercapacitor, it shows a specific capacitance of 258 F g-1 at 1 A g-1 with 76.4% retention at 40 A g-1 in 6 M KOH electrolyte, and delivers a maximum energy density of 24.3 W h kg-1 at a power density of 612.8 W kg-1 in 1 M TEABF4/AN electrolyte. This work provides a new strategy for the synthesis of multiscale porous ACs for high-performance supercapacitors or other energy storage and conversion devices and is expected to be applied on other biomasses for large-scale production.

9.
RSC Adv ; 9(5): 2763, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-35532510

RESUMEN

[This corrects the article DOI: 10.1039/C8RA09663E.].

10.
Laser Photon Rev ; 8(5): 717-725, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25793015

RESUMEN

The spatial and temporal coherence of the fluorescence emission controlled by a quasi-two-dimensional hybrid photonic-plasmonic crystal structure covered with a thin fluorescent-molecular-doped dielectric film is investigated experimentally. A simple theoretical model to describe how a confined quasi-two-dimensional optical mode may induce coherent fluorescence emission is also presented. Concerning the spatial coherence, it is experimentally observed that the coherence area in the plane of the light source is in excess of 49 µm2, which results in enhanced directional fluorescence emission. Concerning temporal coherence, the obtained coherence time is 4 times longer than that of the normal fluorescence emission in vacuum. Moreover, a Young's double-slit interference experiment is performed to directly confirm the spatially coherent emission. This smoking gun proof of spatial coherence is reported here for the first time for the optical-mode-modified emission.

11.
Food Funct ; 4(6): 960-71, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23673419

RESUMEN

High temperature and pH modification could produce functional pectins. In this study, high temperature-modified (HTCP) and pH-modified (MCP) citrus pectins were prepared for studying their anti-tumor activities in eight cancer cell lines and a mouse Sarcoma-180 (S-180) tumor model. HTCP inhibited the proliferation of these cancer cells and induced a caspase-3-dependent cell apoptosis and cell cycle arrest at G2/M phase. It also inhibited the growth of S-180 tumor to 49% of the control at the dose of 200 mg kg(-1) d(-1) and extended the survival time of the tumor-bearing mice. MCP had no anti-proliferative effects on these cancer cells and no anti-tumor effect in the mouse model. The anti-tumor activity of HTCP in the mouse tumor model was not correlated with immunomodulation and galectin-3 inhibition, but correlated well with proliferation inhibition. HTCP might be exploited as a functional food for cancer prevention and/or treatment.


Asunto(s)
Neoplasias/tratamiento farmacológico , Pectinas/administración & dosificación , Pectinas/química , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/genética , Caspasa 3/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Masculino , Ratones , Ratones Endogámicos ICR , Neoplasias/enzimología , Neoplasias/genética , Neoplasias/fisiopatología , Pectinas/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Temperatura
12.
Int J Biol Macromol ; 52: 99-106, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23072731

RESUMEN

A (1→6)-ß-D-glucan (WPLE-N-1) and two mannogalactoglucans (WPLE-N-2 and WPLE-N-3) were isolated from the basidiocarps of Lentinus edodes by hot water extraction, ethanol precipitation, anion exchange chromatography, and further purified by gel-permeation chromatography (GPC). Their structural features were investigated by high performance liquid chromatography (HPLC), high performance gel-permeation chromatography (HPGPC), methylation analysis, periodate oxidation-Smith degradation, Fourier transform-infrared (FT-IR) and NMR spectroscopy, including two-dimensional (2D) NMR. HPLC analysis revealed that WPLE-N-1 was mainly composed of glucose (92%) with small amount of galactose (3.9%) and mannose (4.1%), WPLE-N-2 and WPLE-N-3 contained mannose-galactose-glucose in the molar ratio of 10:27:63 and 5:12:83, respectively. GPC and HPGPC showed that WPLE-N-1, WPLE-N-2 and WPLE-N-3 are homogeneous fractions and their molecular weights were estimated to be 757.5 kDa, 20.9 kDa and 4.7 kDa, respectively. Chemical and spectroscopic studies indicated that WPLE-N-1 consisted of (1→6)-ß-D-glucopyranosyl residues; while WPLE-N-2 and WPLE-N-3 were found to contain (1→6)-, (1→4)- and (1→3)-α-D-glucopyranosyl residues, (1→6)-α-D-galactopyranosyl residues, (1→3,6)- and (1→2,4)-α-D-mannopyranosyl residues and terminal residues of D-glucopyranosyl residues. On a preliminary bioactivity test, these three polysaccharides exhibited antitumor activity against Sarcoma S-180, Carcinoma HCT-116 and HT-29 in vitro. This finding suggests that mannogalactoglucan should be explored as potential antitumor agents and utilized as tumor cell growth inhibitors for food and pharmaceutical industries.


Asunto(s)
Antineoplásicos , Proliferación Celular/efectos de los fármacos , Polisacáridos Fúngicos , Hongos Shiitake/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Conformación de Carbohidratos , Línea Celular Tumoral , Polisacáridos Fúngicos/química , Polisacáridos Fúngicos/aislamiento & purificación , Polisacáridos Fúngicos/farmacología , Humanos
14.
Glycoconj J ; 29(5-6): 357-64, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22684214

RESUMEN

Panax ginseng C. A. Meyer is a well-known plant medicine in the world. Ginseng polysaccharides mainly contain starch-like glucan and pectin. In this paper, a novel glucan WGPA-UH-N1 was purified from ginseng pectin by the treatment of de-esterification and endo-polygalacturonase, followed by the chromatographies on DEAE-Sepharose Fast Flow and Sephadex G-50 column. WGPA-UH-N1 has molecular weight about 17 kDa. WGPA-UH-N1 was determined to be a linear α-(1→6)-D-glucan without side chains by FT-IR, (13)C-NMR, (1)H-NMR, HMQC and HMBC spectra. It is the first time to isolate a linear α-(1→6)-D-glucan from Panax ginseng C. A. Meyer. Immunological activity assays showed that WGPA-UH-N1, although not effective on the phagocytosis of macrophage, could significantly induce lymphocyte proliferation without mitogenic stimuli at 1.0 mg/mL or with LPS at 0.5 mg/mL, also significantly increase NO production at the range of 0.1-1.0 mg/mL in a dose-dependent manner. The immunological activities of WGPA-UH-N1 are different from those of the ß-(1→6)-D-glucan (BIWP2) isolated from the fruit bodies of Bulgaria Inquinans (Fries).


Asunto(s)
Glucanos/química , Factores Inmunológicos/química , Panax/química , Animales , Ascomicetos/química , Proliferación Celular/efectos de los fármacos , Cromatografía , Glucanos/aislamiento & purificación , Glucanos/farmacología , Factores Inmunológicos/aislamiento & purificación , Factores Inmunológicos/farmacología , Linfocitos/citología , Linfocitos/efectos de los fármacos , Macrófagos/citología , Macrófagos/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos ICR , Peso Molecular , Óxido Nítrico , Fagocitosis/efectos de los fármacos , Poligalacturonasa/química , Espectroscopía Infrarroja por Transformada de Fourier
15.
Blood Cells Mol Dis ; 47(3): 198-204, 2011 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21783390

RESUMEN

Mutations of the TMPRSS6 gene are considered the major genetic factors for iron-refractory iron deficiency anemia (IRIDA). Artificial clone libraries containing 17 known mutations of the TMPRSS6 gene were used to develop a high-resolution melting (HRM) assay for the detection of 17 TMPRSS6 gene mutations. The melting temperatures and melting curves were able to distinguish the different genotypes of the 17 TMPRSS6 gene mutations. We used replicate experiments to evaluate the reproducibility of the assay, and the coefficients of variation were in the range 0.0091% to 0.0873%. A total of 145 Chinese patients with IDA were screened with this assay and no TMPRSS6 gene causative mutation was found in any patient. The HRM assay was proved to be rapid, accurate and cost-effective method to identify the TMPRSS6 gene mutations and can be used in the clinical diagnosis of IRIDA.


Asunto(s)
Anemia Ferropénica/genética , Análisis Mutacional de ADN/métodos , Técnicas de Genotipaje/métodos , Proteínas de la Membrana , Serina Endopeptidasas , Adolescente , Adulto , Pueblo Asiatico/genética , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Proteínas de la Membrana/análisis , Proteínas de la Membrana/genética , Mutación , Polimorfismo de Nucleótido Simple/genética , Reproducibilidad de los Resultados , Serina Endopeptidasas/análisis , Serina Endopeptidasas/genética
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