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101.
Giovanna Calabrese Raffaella Giuffrida Debora Lo Furno Nunziatina Laura Parrinello Stefano Forte Rosario Gulino Cristina Colarossi Luciana Rita Schinocca Rosario Giuffrida Venera Cardile Lorenzo Memeo 《International journal of molecular sciences》2015,16(7):15609-15624
The Low-Affinity Nerve Growth Factor Receptor (LNGFR), also known as CD271, is a member of the tumor necrosis factor receptor superfamily. The CD271 cell surface marker defines a subset of multipotential mesenchymal stromal cells and may be used to isolate and enrich cells derived from bone marrow aspirate. In this study, we compare the proliferative and differentiation potentials of CD271+ and CD271− mesenchymal stromal cells. Mesenchymal stromal cells were isolated from bone marrow aspirate and adipose tissue by plastic adherence and positive selection. The proliferation and differentiation potentials of CD271+ and CD271− mesenchymal stromal cells were assessed by inducing osteogenic, adipogenic and chondrogenic in vitro differentiation. Compared to CD271+, CD271− mesenchymal stromal cells showed a lower proliferation rate and a decreased ability to give rise to osteocytes, adipocytes and chondrocytes. Furthermore, we observed that CD271+ mesenchymal stromal cells isolated from adipose tissue displayed a higher efficiency of proliferation and trilineage differentiation compared to CD271+ mesenchymal stromal cells isolated from bone marrow samples, although the CD271 expression levels were comparable. In conclusion, these data show that both the presence of CD271 antigen and the source of mesenchymal stromal cells represent important factors in determining the ability of the cells to proliferate and differentiate. 相似文献
102.
Chris Ying Cao May Lei Mei Quan-Li Li Edward Chin Man Lo Chun Hung Chu 《International journal of molecular sciences》2015,16(3):4615-4627
This study aimed to review the laboratory methods on biomimetic remineralization of demineralized human dentine. A systematic search of the publications in the PubMed, TRIP, and Web of Science databases was performed. Titles and abstracts of initially identified publications were screened. Clinical trials, reviews, non-English articles, resin-dentine interface studies, hybrid layer studies, hybrid scaffolds studies, and irrelevant studies were excluded. The remaining papers were retrieved with full texts. Manual screening was conducted on the bibliographies of remaining papers to identify relevant articles. A total of 716 studies were found, and 690 were excluded after initial screening. Two articles were identified from the bibliographies of the remaining papers. After retrieving the full text, 23 were included in this systematic review. Sixteen studies used analogues to mimic the functions of non-collagenous proteins in biomineralization of dentine, and four studies used bioactive materials to induce apatite formation on demineralized dentine surface. One study used zinc as a bioactive element, one study used polydopamine, and another study constructed an agarose hydrogel system for biomimetic mineralization of dentine. Many studies reported success in biomimetic mineralization of dentine, including the use of non-collagenous protein analogues, bioactive materials, or elements and agarose hydrogel system. 相似文献
103.
Hernán G. Góngora Pablo Ledesma Victor R. Lo Valvo Ana E. Ruiz Javier D. Breccia 《Food and Bioproducts Processing》2012,90(4):767-772
Sixteen strains of lactic acid bacteria were evaluated for their capacity of acidification of Merluccius hubbsi fish wastes obtained from a processing factory. Only three lactobacilli (Lactobacillus buchneri B-1837, Lactobacillus arizonensis B-14768 and Lactobacillus plantarum B-4496) were able to reduce the pH value to 4.0 or below when using glucose or sucrose as carbon source. Either with only 25 g l?1 of glucose or sucrose, L. arizonensis B-14768 reduced the pH to 3.8 ± 0.2 within 24 h of fermentation. The acid tolerance test (pH 3.0 at 37 °C) for the strains presented DpH3-values of 192, 383 and 767 min for L. buchneri, L. plantarum and L. arizonensis, respectively. However, at a lower pH value (pH 2.0) only L. arizonensis was significantly recovered after 45 min of exposure (DpH2 68 min). Considering together the acidification capacity, the tolerance to other stresses (heat and bile salts) and the lower optimum temperature for the process, L. arizonensis is described as a suitable strain for M. hubbsi silage; constituting a promissory alternative for fish fermentation at location with temperate or cold climes. 相似文献
104.
L Tamborini A Pinto TK Smith LL Major MC Iannuzzi S Cosconati L Marinelli E Novellino L Lo Presti PE Wong MP Barrett C De Micheli P Conti 《ChemMedChem》2012,7(9):1623-1634
Acivicin analogues with an increased affinity for CTP synthetase (CTPS) were designed as potential new trypanocidal agents. The inhibitory activity against CTPS can be improved by increasing molecular complexity, by inserting groups able to establish additional interactions with the binding pocket of the enzyme. This strategy has been pursued with the synthesis of α‐amino‐substituted analogues of Acivicin and N1‐substituted pyrazoline derivatives. In general, there is direct correlation between the enzymatic activity and the in vitro anti‐trypanosomal efficacy of the derivatives studied here. However, this cannot be taken as a general rule, as other important factors may play a role, notably the ability of uptake/diffusion of the molecules into the trypanosomes. 相似文献
105.
The mammalian cell cycle is important in controlling normal cell proliferation and the development of various diseases. Cell cycle checkpoints are well regulated by both activators and inhibitors to avoid cell growth disorder and cancerogenesis. Cyclin dependent kinase 20 (CDK20) and p21Cip1/Waf1 are widely recognized as key regulators of cell cycle checkpoints controlling cell proliferation/growth and involving in developing multiple cancers. Emerging evidence demonstrates that these two cell cycle regulators also play an essential role in promoting cell survival independent of the cell cycle, particularly in those cells with a limited capability of proliferation, such as cardiomyocytes. These findings bring new insights into understanding cytoprotection in these tissues. Here, we summarize the new progress of the studies on these two molecules in regulating cell cycle/growth, and their new roles in cell survival by inhibiting various cell death mechanisms. We also outline their potential implications in cancerogenesis and protection in heart diseases. This information renews the knowledge in molecular natures and cellular functions of these regulators, leading to a better understanding of the pathogenesis of the associated diseases and the discovery of new therapeutic strategies. 相似文献
106.
Low-Temperature Sintering and Microwave Dielectric Properties of Anorthite-Based Glass-Ceramics 总被引:6,自引:0,他引:6
Chung-Lun Lo Jenq-Gong Duh Bi-Shiou Chiou Wen-Hsi Lee 《Journal of the American Ceramic Society》2002,85(9):2230-2235
TiO2 nucleated anorthite-based glass-ceramics were fabricated from glass powders. After sintering and crystallization heat treatment, various physical properties, including apparent bulk density and water absorption, were examined to evaluate the sintering behavior of anorthite-based glass-ceramic. Results showed that the complete-densification temperature for specimens was as low as 900°C. Sufficient crystallization was achieved by subsequently raising the firing temperature to 950°C, and the dielectric quality factor was promoted to the maximum value. Contents of nucleating agent (TiO2 ) played an important role in the dielectric constants. The crystallinity was controlled by raising the firing temperature at a constant heating rate. The degree of crystallization affected the dielectric properties of sintered glass-ceramics. At the resonant frequency of 10 GHz, anorthite glass-ceramics with 5 wt% TiO2 possessed the lowest permittivity of 8 and exhibited appropriate dielectric properties as compared with those with B2 O3 and 10 wt% TiO2 . 相似文献
107.
Environmental factors such as oxygen, temperature, and microbial species may have significant effects on decomposition of biodegradable polymers. A representative biodegradable, thermoplastic polymer, poly(3‐hydroxybutyrate‐co‐hydroxyvalerate) (PHBV), was decomposed in an aqueous medium under controlled laboratory conditions by soil microbes for the intrinsic degradation kinetics and the effects of the environmental factors on polymer biodegradation. The amount of proteins, including the PHBV depolymerases, that attached to the polymer surfaces was quite constant during the period of significant mass loss of the polymer specimens. The microbial polymer degradation followed a zero‐order rate model, so the residual mass fraction of PHBV films declined linearly with time. The mixed aerobic microbial organisms from fertile soil showed a higher activity of polymer degradation than an aerobic PHBV‐producing bacterium and the mixed anaerobes in the same soil. The mixed anaerobic microorganisms from barren soil decomposed the polymer at a slower rate than the anaerobes from fertile soil, and this was attributed to fewer microbial cells in the barren soil instead of the difference in the microbial species. The temperature effect on PHBV degradation can be described with an Arrhenius equation, and the activation energy is around 16 kcal/mol. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 205–213, 2003 相似文献
108.
Susanna K. P. Lau Kim-Chung Lee George C. S. Lo Vanessa S. Y. Ding Wang-Ngai Chow Tony Y. H. Ke Shirly O. T. Curreem Kelvin K. W. To Deborah T. Y. Ho Siddharth Sridhar Sally C. Y. Wong Jasper F. W. Chan Ivan F. N. Hung Kong-Hung Sze Ching-Wan Lam Kwok-Yung Yuen Patrick C. Y. Woo 《International journal of molecular sciences》2016,17(3)
To identify potential biomarkers for improving diagnosis of melioidosis, we compared plasma metabolome profiles of melioidosis patients compared to patients with other bacteremia and controls without active infection, using ultra-high-performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry. Principal component analysis (PCA) showed that the metabolomic profiles of melioidosis patients are distinguishable from bacteremia patients and controls. Using multivariate and univariate analysis, 12 significant metabolites from four lipid classes, acylcarnitine (n = 6), lysophosphatidylethanolamine (LysoPE) (n = 3), sphingomyelins (SM) (n = 2) and phosphatidylcholine (PC) (n = 1), with significantly higher levels in melioidosis patients than bacteremia patients and controls, were identified. Ten of the 12 metabolites showed area-under-receiver operating characteristic curve (AUC) >0.80 when compared both between melioidosis and bacteremia patients, and between melioidosis patients and controls. SM(d18:2/16:0) possessed the largest AUC when compared, both between melioidosis and bacteremia patients (AUC 0.998, sensitivity 100% and specificity 91.7%), and between melioidosis patients and controls (AUC 1.000, sensitivity 96.7% and specificity 100%). Our results indicate that metabolome profiling might serve as a promising approach for diagnosis of melioidosis using patient plasma, with SM(d18:2/16:0) representing a potential biomarker. Since the 12 metabolites were related to various pathways for energy and lipid metabolism, further studies may reveal their possible role in the pathogenesis and host response in melioidosis. 相似文献
109.
New alginate foams: Box‐Behnken design of their manufacturing; fire retardant and thermal insulating properties 下载免费PDF全文
Thierry Vincent Loïc Dumazert Ludivine Dufourg Claire Cucherat Rodolphe Sonnier Eric Guibal 《应用聚合物科学杂志》2018,135(7)
A new method for preparing alginate foams with progressive release of copper in the presence of sodium lauryl sulfate (SLS, foaming agent) has been designed. Copper acts as the ionotropic gelling agent through the reaction of copper carbonate with gluconolactone. The process does not require freeze‐drying contrarily to the conventional method used for preparing macroporous alginate foams. The new materials investigated in this study have remarkable thermal properties, including thermal conductivity lower than 0.041 W m?1 K?1 and low heat release (below 2 kJ g?1), which allows labeling these foams self‐extinguishing materials. An experimental design methodology, based on a Box‐Behnken plan with three parameters and three levels, is successfully used for evaluating the impact of the amounts of alginate, SLS, and copper carbonate on the productivity, apparent density, and shrinking at air‐drying. It yielded an optimization of the process for the manufacturing of light, and stable/rigid insulating and thermally stable materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45868. 相似文献
110.
A highly insoluble metalloporphyrin polymeric material was used as sorbent for the solid‐phase extraction of phenolic compounds. Substantial quantities of phenols (40 to 60 mg/g polymer) were absorbed from aqueous solution comparing satisfactorily with other extraction methods. The polymeric phase presented similar KSPE values for the hydrophobic compounds tested such as p‐chlorophenol, BPA, p‐nitrophenol, and a significant lower value for the more hydrophilic p‐aminophenol and cresol. Several metallic complexes of protoporphyrin IX (Co2+, Cu2+, Ni2+, Zn2+, and Fe3+) have been tested. The analytes were extracted with high recoveries at acid and neutral pH values, whereas at pH 10 low recoveries were obtained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3038–3043, 2001 相似文献