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71.
More than 70 % of women with ovarian cancer are diagnosed with advanced-stage disease, which is initially treated with cytoreductive surgery, and combination chemotherapy with platinum-based compounds. Most patients initially respond to platinum-based therapy, but eventually up to 80 % of this responsive cohort becomes refractory due to the development of platinum resistance. This review discusses current and potential therapeutic approaches that exploit biomaterial-based applications to combat platinum resistance either by enhancing the delivery of platinum-based drugs or prodrugs, delivering other toxic non-platinum-based bioactive factors (by themselves or in combination with platinum-based drugs) or by delivering other bioactive factors that re-sensitize resistant ovarian cancer cells to these drugs. The types of materials that are used, the bioactive factors applied (i.e., drug or gene delivery), and the specific agents that are employed to target these types of cancer cells are discussed. We conclude that the unique attributes of biomaterial-based applications can be further explored toward overcoming platinum-resistant ovarian cancer as monotherapy, or in combination with other treatment strategies. 相似文献
72.
Carolina Tallon Monika Limacher George V. Franks 《Journal of the European Ceramic Society》2010,30(14):2819-2826
The effect of the nanometric-ranged particle size of the starting powder through a simple and well-established shaping method, slip casting, has been studied. Several alumina suspensions with the same viscosity (but different solid content suspensions) and different particle size (11, 44, 190 and 600 nm) were prepared and shaped into a dense body. The green and sintered densities ranged between 30–67% and 63–99% of the theoretical value, respectively. These values, together with the microstructure observations reveal the effect of the solid content of the suspensions and the characteristics of the ceramic powder, leading to the determination of an optimal particle size. Based on both processability (rheological behaviour) and microstructure (density and grain size) it has been determined that particles with sizes ranging 100–300 nm are the best for preparing concentrated suspensions with low viscosity and bodies with density close to the theoretical value when using conventional pressureless sintering densification. 相似文献
73.
Kinetic,thermodynamic parameters and in vitro digestion of tannase from Aspergillus tamarii URM 7115
Amanda Reges de Sena Tonny Cley Campos Leite Talita Camila Evaristo da Silva Nascimento Anna Carolina da Silva Catiane S. Souza Antônio Fernando de Mello Vaz 《Chemical Engineering Communications》2018,205(10):1415-1431
Tannase is an enzyme used in various industries and produced by a large number of microorganisms. The aim of this study was to evaluate tannase production to determine the biochemical, kinetic, and thermodynamic properties and to simulate tannase in vitro digestion. The tannase-producing fungal strain was isolated from “jamun” leaves and identified as Aspergillus tamarii. Temperature at 26°C for 67?h was the best combination for maximum tannase activity (6.35-fold; initial activity in Plackett–Burman design—15.53?U/mL and average final activity in Doehlert design—98.68?U/mL). The crude extract of tannase was optimally active at 40°C, pH 5.5 and 6.5. Moreover, tannase was stimulated by Na+, Ca2+, Mg2+, and Mn2+. The half-life at 40°C lasted 247.55?min. The free energy of Gibbs, enthalpy, and entropy, at 40°C, was 81.47, 16.85, and ?0.21?kJ/mol?·?K, respectively. After total digestion, 123.95% of the original activity was retained. Results suggested that tannase from A. tamarii URM 7115 is an enzyme of interest for industrial applications, such as gallic acid production, additive for feed industry, and for beverage manufacturing, due to its catalytic and thermodynamic properties. 相似文献
74.
Dr. Md Kausar Alam Carolina Gonzalez Wayne Hill Dr. Ayman El-Sayed Dr. Humphrey Fonge Dr. Kris Barreto Prof. Dr. C. Ronald Geyer 《Chembiochem : a European journal of chemical biology》2017,18(22):2217-2221
Efforts to engineer recombinant antibodies for specific diagnostic and therapy applications are time consuming and expensive, as each new recombinant antibody needs to be optimized for expression, stability, bio-distribution, and pharmacokinetics. We have developed a new way to construct recombinant antibody-like “devices” by using a bottom-up approach to build them from well-behaved discrete recombinant antibody domains or “parts”. Studies on antibody structure and function have identified antibody constant and variable domains with specific functions that can be expressed in isolation. We used the SpyTag/SpyCatcher protein ligase to join these parts together, thereby creating devices with desired properties based on summed properties of parts and in configurations that cannot be obtained by using genetic engineering. This strategy will create optimized recombinant antibody devices at reduced costs and with shortened development times. 相似文献
75.
Ana C. Lo Prete Clederson H. Dina Carolina H. Azevedo Camila G. Puk Neuza H. M. Lopes Whady A. Hueb Raul Cavalcante Maranhão 《Lipids》2009,44(10):917-924
The exchange of lipids with cells and other lipoproteins is a crucial process in HDL metabolism and for HDL antiatherogenic
function. Here, we tested a practical method to quantify the simultaneous transfer to HDL of phospholipids, free-cholesterol,
esterified cholesterol and triacylglycerols and to verify the lipid transfer in patients with coronary artery disease (CAD)
or undergoing statin treatment. Twenty-eight control subjects without CAD, 27 with CAD and 25 CAD patients under simvastatin
treatment were studied. Plasma samples were incubated with a donor nanoemulsion prepared by ultrasonication of the constituent
lipids and labeled with radioactive lipids; % lipids transferred to HDL were quantified in the HDL-containing supernatant
after chemical precipitation of non-HDL fractions and the nanoemulsion. The assay was precise and reproducible. Increase of
temperature (4–37 °C), of incubation period (5 min to 2 h), of HDL-cholesterol concentration (33–244 mg/dL) and of mass of
nanoemulsion lipids (0.075–0.3 mg/μL) resulted in increased lipid transfer from the nanoemulsion to HDL. In contrast, increasing
pH (6.5–8.5) and albumin concentration (3.5–7.0 g/dL) did not affect lipid transfer. There was no difference between CAD and
control non-CAD with regard to the lipid transfer, but statin treatment reduced the transfer to HDL of all four lipids. The
test herein described is a valid and practical tool for exploring an important aspect of HDL metabolism. 相似文献
76.
Marcela Boroski Ana Carolina de AguiarJoana Schuelter Boeing Eliza Mariane RottaCamila Leite Wibby Elton Guntendorfer BonaféNilson Evelázio de Souza Jesuí Vergílio Visentainer 《Food chemistry》2011
Five different pasta formulations were prepared using different concentrations of carrot leaf meal (CLM) and oregano leaf meal (OLM). One control formulation (wheat flour and semolina, 70:30 w/w) and four other formulations were prepared using the following amounts of leaf meals: 5% CLM and 5% OLM (I), 10% CLM (II), 10% OLM (III), and 10% CLM, 10% OLM (IV). The highest content of alpha-linolenic acid was found in formulations II and IV, which also had a reduced n-6/n-3 ratio, 3.6 (IV), when compared to the control, which was 19.8. All the samples enhanced with leaf meals showed antioxidant activity by the DPPH radical method; however, it was higher in formulation IV, which was the same observed for phenolic compounds. Pasta added with leaf meals lost more solubles, had shorter cooking time and a lower weight increase than the control pasta. All formulations had significant sensory acceptance. 相似文献
77.
Stephen Tanurdjaja Carolina Tallon Peter J. Scales George V. Franks 《Advanced Powder Technology》2011,22(4):476-481
The surface of alumina, which is hydrophilic in general, was made hydrophobic either by adsorption of polymer (phys-adsorption) or by an alkylation reaction with alcohol (chem-adsorption) to enable dispersion in dodecane. Hypermer A70 (8.2 nm) was used as the polymer and 1-octanol (1.2 nm), 1-decanol (1.5 nm) and 1-hexadecanol (2.5 nm) were used as the alcohol (values in brackets are the approximate thickness of the steric barrier). Rheological measurements of ceramic suspensions indicate that it is possible to achieve a high solid loading (50 vol.%) with relatively low viscosity (0.25 Pa s at 100 s?1, the typical shear rate for pumping of liquids in pipes) as long as the stabilising molecule is large enough. The observed rheological behaviour fitted the Quemada viscosity model quite well when excluded volume effects were taken into account. Addition of 2.8 wt.% of Hypermer A70 with respect to weight of alumina was enough to stabilise the particles. 相似文献
78.
The effect of chlorine and oxygen concentrations on the removal of mercury at an FGD-batch reactor 总被引:2,自引:0,他引:2
A series of laboratory scale experiments were conducted in an FGD-batch reactor. A synthetic flue gas was produced and directed through a CaCO3 suspension contained in a glass reactor vessel. The suspension temperature was set at 54 °C through a water bath. In order to observe the distribution of mercury species in the system, solid, liquid and gaseous samples were taken and analysed. For gaseous mercury determination, continuous measurements were carried out, up and downstream the reactor. Furthermore, the concentration of chlorine in the scrubber solution of the system was varied from 0 to 62 g/l under different oxidative conditions.In a first approach, a concentration drop of elemental mercury coming out of the system was observed. The latter occurs only when high concentrations of Cl− are present, combined with a high O2 availability in the scrubber. It was also observed that mercury species distribution in the different phases varies, depending on the available chemical form of chlorine and oxygen concentration. 相似文献
79.
Spectrophotometric data followed by a suitable treatment of chemometric analysis were used for the simultaneous determination of monosodium glutamate (MSG), guanosine 5′-monophosphate (GMP) and inosine 5′-monophosphate (IMP) in stock cube samples, without any previous extraction step. By this way, the overlapping of the absorption spectra was resolved using a PLS-1 model. The concentration for experimental calibration matrix were varied between 5.03–34.2 μg mL−1 for IMP and GMP, and 448–1399 μg mL−1 for MSG. The relative errors of prediction (REPCV %) were 1.8, 2.8 and 3.1 for IMP, GMP and MSG, respectively. 相似文献
80.
Today, in addition to traditional mobile services, there are new ones already being used, thanks to the advances in 3G-related technologies. Our work contributed to the emerging body of research by integrating TAM and Diffusion Theory. Based on a sample of 542 Dutch consumers, we found that traditional antecedents of behavioral intention, ease of use and perceived usefulness, can be linked to diffusion-related variables, such as social influence and perceived benefits (flexibility and status). 相似文献