The influence of folic acid and vitamin B<SUB>12</SUB> on nucleic acid metabolism in microorganisms

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A Mini-Review: Comparison between curcumin and tetrahydrocurcumin based on their activities

Curcumin, a natural ingredient present in turmeric rhizome is known for its various therapeutic activities such as antioxidant, anti-inflammatory, anticancer, antidiabetic, NF-kB activation suppresser. The hydrogenated derivative of curcumin, i.e., tetrahydrocurcumin, is also found to reveal the same activities. Moreover, the pro-oxidant effect of curcumin is reported, whereas tetrahydrocurcumin does not show any pro-oxidant effects. This contrasting behaviour of the two is attributed to their structures, because conjugation is involved only in curcumin, not in the tetrahydrocurcumin. It can be evidently concluded that double bonds affect the keto-enol ratio of the molecules and are therefore responsible for the degradation of curcumin, whereas tetrahydrocurcumin remains stable. Nevertheless, these double bonds are liable to affect the kinetics of beneficial activities of curcumin and tetrahydrocurcumin

Mapping solar irradiance within Schrödinger Basin for future robotic sample return missions

The US National Research Council (NRC) identified eight scientific concepts and thirty-five prioritized investigations to be addressed with continued lunar exploration. These objectives are broadly consistent with those identified throughout the international community. the majority of these objectives require sample return from the Moon. Schrödinger basin has been highlighted as a particularly attractive location to find suitable samples

Structure-based stabilization of insulin as a therapeutic protein assembly via enhanced aromatic-aromatic interactions

Key contributions to protein structure and stability are provided by weakly polar interactions, which arise from asymmetric electronic distributions within amino acids and peptide bonds. Of particular interest are aromatic side chains whose directional π-systems commonly stabilize protein interiors and interfaces. Here, we consider aromatic-aromatic interactions within a model protein assembly: the dimer interface of insulin. Semi-classical simulations of aromatic-aromatic interactions at this interface suggested that substitution of residue TyrB26 by Trp would preserve native structure while enhancing dimerization (and hence hexamer stability). The crystal structure of a [TrpB26]insulin analog (determined as a T3Rf3 zinc hexamer at a resolution of 2.25 Å) was observed to be essentially identical to that of WT insulin. Remarkably and yet in general accordance with theoretical expectations, spectroscopic studies demonstrated a 150-fold increase in the in vitro lifetime of the variant hexamer, a critical pharmacokinetic parameter influencing design of long-acting formulations. Functional studies in diabetic rats indeed revealed prolonged action following subcutaneous injection. The potency of the TrpB26-modified analog was equal to or greater than an unmodified control. Thus, exploiting a general quantum-chemical feature of protein structure and stability, our results exemplify a mechanism-based approach to the optimization of a therapeutic protein assembly

Thy-1 Expressing Mesenchymal Cells in Rat Nephrogenesis in Correlation with Cells Immunoreactive for α-Smooth Muscle Actin and Vimentin

Thy-1 expression may influence myofibroblast development. Through the epithelial-mesenchymal transition (EMT), injured renal epithelial cells undergo regression to the metanephric mesenchymal phenotype and then acquire a myofibroblastic nature (expressing α-smooth muscle actin; α-SMA). Because the metanephric blastema differentiates into mesenchymal and renal epithelial cells, we investigated Thy-1 immunoexpression during nephrogenesis in F344 rats in correlation with vimentin and α-SMA expressions. Kidney samples were obtained from fetuses on gestation days 18 and 21, neonates on days 1-18 and adults at 6 weeks of age. Mesangial cells in S-shaped bodies and immature and mature glomeruli continuously expressed both Thy-1 and α-SMA during early nephrogenesis (fetuses and neonates on days 1-9). During early nephrogenesis, loosely-arranged blastemal cell-derived mesenchymal cells in the cortex and medulla also exhibited Thy-1 and α-SMA, although the α-SMA expression was weaker than that of Thy-1. Vimentin expression coincided with that of Thy-1. These findings indicate that the derivation of α-SMA-expressing myofibroblastic cells may be related to mesangial or blastemal cells expressing both Thy-1 and α-SMA. Interestingly, there was a difference in Thy-1 expression between cortical and medullary tubulointerstitial cells from late nephrogenesis (neonates on days 12-18) and those from adults in that the cortical cells reacted faintly or negatively to Thy-1, whereas the medullary cells reacted strongly to Thy-1; additionally, bundle-arranged mesenchymal cells that were only observed in the neonates on days 1-12 reacted strongly to α-SMA, but faintly to Thy-1. Blastemal cell-derived mesenchymal cells seem to alter the immunoexpressions of Thy-1 and α-SMA, depending on the conditions which they develop. Thy-1 immunoexpression would be useful for investigation of reverse embryogenesis, which might occur in fibrotic kidneys

Laser cladding of Ni based powder on a Cu-Ni-Al glassmold: Influence of the process parameters on bonding quality and coating geometry

International audienceLaser cladding of a Ni based powder on cupro-nickel-aluminum (Cu-Ni-Al) substrate was performed with a 4 kW continuous laser. The Cu-Ni-Al alloy is used for its thermal properties in glass mold industry. The role of the Ni based alloy clad is to protect the mold without affecting its thermal properties by limiting the heat-affected zone. The objective of this research is to produce a well bonded Ni based melted powder without pores or cracks and with a very small dilution zone on a non-planar surface (curved section). The impact of the process parameters such as laser power, scanning speed and powder feeding rate on the coating geometry was investigated with an experimental design technique analysis using the ANOVA (Analysis of variance) method. It was used to determine and represent the influence of each process parameter on the coating geometry (width, height) and the bonding quality. This ANOVA analysis led to a parameter combination to optimize the bonding quality between the Ni coating and the Cu-Ni-Al substrate taking into account the industrial geometrical constraints. More, an analytical calculation allowed to estimate the power necessary for bonding as a function of laser scanning speed and powder feeding rate

Synergistic Antioxidant Activity of Capsicum Oleoresin, Lecithin and Curcuminoids in Sunflower Oil

Essential fatty acids (EFAs) have the tendency to undergo autoxidation. Hence, the addition of antioxidants becomes a key step during their storage. Synthetic antioxidants are found to be toxic in nature. Recently, many investigations were carried out where EFAs were stabilized by natural antioxidants those can even replace synthetic antioxidant totally. In the present study, capsicum oleoresin, soy lecithin and curcuminoids were used to stabilize EFAs in refined sunflower oil. The study showed that the synergism of these natural antioxidants in proper proportion increased the shelf life of sunflower oil. Consequently, the nutritive value of EFAs was restored because of their effective stabilization and the natural antioxidants added for their stabilization provided the medicinal benefits

Proof firm downsizing and diagnosis-specific disability pensioning in Norway

&lt;br&gt;Background: We wanted to investigate if firm downsizing is related to an increased rate of disability pensions among the former employed, especially for those with musculoskeletal and psychiatric diagnoses, and for those having to leave the firm.&lt;/br&gt; &lt;br&gt;Methods: Statistics Norway provided a linked file with demographic information and all social security grants from the National Insurance Administration for 1992–2004 for all inhabitants in Norway. Our sample was aged 30–55 years in 1995, being alive, employed and not having a disability pension at the end of 2000. Downsizing was defined as percent change in number of employed per firm from 1995 to end 2000. Employment data were missing for 25.6% of the sample.&lt;/br&gt; &lt;br&gt;Results: Disability pension rates in the next four years were 25% higher for those experiencing a 30-59% downsizing than for those not experiencing a reduction of the workforce. 1-29% and 60-100% downsizing did not have this effect. Stayers following down-sizing had higher disability pension rates than leavers. What we have called complex musculoskeletal and psychiatric diagnoses were relatively most common.&lt;/br&gt; &lt;br&gt;Conclusion: Moderate downsizing is followed by a significant increase in disability pension rates in the following four years, often with complex musculoskeletal and psychiatric diagnoses.&lt;/br&gt