Ultrafine powders of nano-crystalline rare earth (Gd+3) doped manganese cobalt ferrite with composition Mn0.5Co0.5Fe2-xGdxO4 (x = 0.00, 0.02, 0.04, 0.06, and 0.08) were synthesized using combustion ...synthesis. Powders obtained through the combustion process were characterized using X-ray diffraction and Fourier transform infrared spectroscopy for structural analysis. Particle size was determined using a Transmission electron microscope (TEM) and was seen to remain in narrow range of 15 nm–30 nm with increasing Gd+3 concentrations. The magnetic alterations triggered by Gd+3 incorporation were studied using a vibrating sample magnetometer (VSM) which showed that the magnetic parameters such as Saturation magnetization (MS) and Coercivity (HC) of the nano-powders depend remarkably on Gd+3 concentrations in the ferrite unit cell. The electrical transport properties such as DC resistivity and dielectric constant were also seen to depend on the extent of rare earth doping in the ferrite material.
•Synthesis of Gd+3 doped Mn–Co Ferrite nanoparticles through combustion method.•Increase in saturation magnetization with increasing Gd+3 concentrations.•Marginal increase in room temperature DC resistivity for higher Gd+3 concentrations.•Reduction in Dielectric constant with increase in Gd+3 concentrations.
The metastatic potential of cancer cells is directly attributed to their ability to invade through the extracellular matrix. The mechanisms regulating this cellular invasiveness are poorly ...understood. Here, we show that junctional adhesion molecule A (JAM-A), a tight junction protein, is a key negative regulator of cell migration and invasion. JAM-A is robustly expressed in normal human mammary epithelium, and its expression is down-regulated in metastatic breast cancer tumors. In breast cancer cell lines, an inverse relationship between JAM-A expression and the ability of these cells to migrate on a collagen matrix was observed, which correlates with the known ability of these cells to metastasize. The T47D and MCF-7 cells, which migrate least, are found to express high levels of JAM-A, whereas the more migratory MDA-MB-468 cells have lower levels of JAM-A on the cell surface. MDA-MB-231 cells, which are highly migratory, express the least amount of JAM-A. Overexpression of JAM-A in MDA-MB-231 cells inhibited both migration and invasion through collagen gels. Furthermore, knockdown of JAM-A using short interfering RNAs enhanced the invasiveness of MDA-MB-231 cells as well as T47D cells. The ability of JAM-A to attenuate cell invasion correlated with the formation of increased numbers of focal adhesions and the formation of functional tight junctions. These results show for the first time that an immunoglobulin superfamily cell adhesion protein expressed at tight junctions could serve as a key negative regulator of breast cancer cell invasion and possibly metastasis. Furthermore, loss of JAM-A could be used as a biomarker for aggressive breast cancer.
Water blown rigid polyurethane foam (PUF) was prepared with melamine polyphosphate (MPP) and melamine cyanurate (MC) as fire retardant (FR) additives. The effect of these additives on the properties ...of rigid PUF such as physico-mechanical, morphological, thermo-oxidative stability, flame retardancy and smoke density properties were studied. The mechanical and thermo-oxidative stability of PUF filled with MC was found to be better than those of MPP filled PUF. The insulation property of both MPP and MC filled PUF was improved with respect to the neat PUF. The FR properties of these filled PUF were evaluated by cone calorimeter, limiting oxygen index (LOI), smoke density, rate of burning and char residue estimation. The FR property of MPP filled PUF was better than that of the MC filled PUF.
This study was designed to examine the interaction of dexamethasone (DEX) with bovine serum albumin (BSA) and human serum albumin (HSA) under physiological conditions with drug concentrations in the ...range of 2.5–20
μM and BSA/HSA was fixed at 5.0
μM. Spectroscopic analysis of the emission quenching at different temperatures revealed that the quenching mechanism of serum albumin by dexamethasone is static quenching mechanism. The binding sites number,
n and binding constant,
K were obtained at various temperatures. The distance
r between dexamethasone and the protein was evaluated according to the theory of Föster energy transfer. The result of fluorescence spectra UV–vis absorption spectra and FT-IR spectra showed that the conformation of bovine serum albumin and human serum albumin has been changed in the presence of dexamethasone. The thermodynamic parameters, free energy change (Δ
G
0), enthalpy change (Δ
H
0) and entropy change (Δ
S
0) for BSA–DEX and HSA–DEX were calculated according to van’t Hoff equation and discussed.
Density is an important parameter that influences the properties and performances of rigid polyurethane foam (PUF). Rigid PUF with different densities were prepared by varying the amount of distilled ...water as blowing agent. This investigation reports the mechanical, morphological, water absorption, thermal conductivity, and thermal behavior of rigid PUF varying with the density, which controls the foam architecture. The density of the PUF decreased from 116 to 42 kg/m³ with an increase in the amount of water from 0.1 to 3.0 parts per hundred polyol by weight (phr), respectively. It was found that the mechanical properties of the PUFs changed with the foam density. The results of water absorption of the PUFs showed that water absorption increased with decrease in density, due to increase in the cell size and decrease in the cell-wall thickness. The thermal conductivity measurements showed that the thermal conductivity decreased with increase in density. It was due to the decrease in cell size. The thermal analysis of the PUFs shows that the glass transition temperature increases with the decrease in foam density, but the thermal stability decreases with the decrease in foam density.
We established a predictive kinetic metabolic-flux model for the 21 enzymes and 24 metabolites of the monolignol biosynthetic pathway using Populus trichocarpa secondary differentiating xylem. To ...establish this model, a comprehensive study was performed to obtain the reaction and inhibition kinetic parameters of all 21 enzymes based on functional recombinant proteins. A total of 104 Michaelis-Menten kinetic parameters and 85 inhibition kinetic parameters were derived from these enzymes. Through mass spectrometry, we obtained the absolute quantities of all 21 pathway enzymes in the secondary differentiating xylem. This extensive experimental data set, generated from a single tissue specialized in wood formation, was used to construct the predictive kinetic metabolic-flux model to provide a comprehensive mathematical description of the monolignol biosynthetic pathway. The model was validated using experimental data from transgenic P. trichocarpa plants. The model predicts how pathway enzymes affect lignin content and composition, explains a longstanding paradox regarding the regulation of monolignol subunit ratios in lignin, and reveals novel mechanisms involved in the regulation of lignin biosynthesis. This model provides an explanation of the effects of genetic and transgenic perturbations of the monolignol biosynthetic pathway in flowering plants.
Patients on dialysis are known to have higher risk for gastrointestinal (GI) bleeding. However, data on mild to moderate CKD, particularly elevated albuminuria, are limited.
Among 11,088 participants ...in the Atherosclerosis Risk in Communities (ARIC) Study, we investigated the association of eGFR and urinary albumin-to-creatinine ratio (ACR) with risk for hospitalization with GI bleeding. Kidney measures were assessed at visit four (1996-1998), and follow-up was continued through 2011.
During a median follow-up of 13.9 years, 686 first incident hospitalizations with GI bleeding were observed (incidence rate, 4.9 per 1000 person-years 95% confidence interval (95% CI), 4.5 to 5.3). Multivariable Cox proportional hazards models revealed that both lower eGFR and higher ACR were associated with higher risk for GI bleeding. With eGFR≥90 ml/min per 1.73 m
as a reference, risk for GI bleeding was significant in moderately decreased eGFR of 30-59 ml/min per 1.73 m
(hazard ratio HR, 1.51; 95% CI, 1.13 to 2.02), and was highest in severely decreased eGFR<30 ml/min per 1.73 m
(HR, 7.06; 95% CI, 3.91 to 12.76). Compared with ACR<10 mg/g, risk for GI bleeding became significantly higher in mild albuminuria with ACR 10-29 mg/g (HR, 1.36; 95% CI, 1.08 to 1.69), and was nearly double in moderate and severe albuminuria (HR, 2.13; 95% CI, 1.66 to 2.71 for ACR 30-299 mg/g, and HR, 2.07; 95% CI, 1.33 to 3.22 for ACR≥300 mg/g). These results were largely consistent in demographic and clinical subgroups and independent of incident cardiovascular events or dialysis during follow-up.
Individuals with even mild to moderate CKD warrant clinical attention regarding the risk of hospitalization with GI bleeding.
Apoptosis signal-regulating kinase 1 (ASK1) is a serine-threonine kinase that is ubiquitously expressed in nucleated cells and is responsible for the activation of multiple mitogen-activated protein ...kinases (MAPK) to regulate cell stress. Activation of ASK1 via cellular stress leads to activation of downstream signaling components, activation of transcription factors, and proinflammatory cytokine production. ASK1 is also expressed in anucleate platelets and is a key player in platelet activation as it is important for signaling. Interestingly, the mechanism of ASK1 activation is cell type-dependent. In this review we will explore how ASK1 regulates a variety of cellular processes from innate immune function to thrombosis and hemostasis. We will discuss how ASK1 influences FcγRIIA-mediated platelet reactivity and how that reactivity drives platelet clearance. Furthermore, we will explore the role of ASK1 in thromboxane (TxA
) generation, which highlights differences in the way ASK1 functions in mouse and human platelets.
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