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171.
Online resources for the bovine genome analysis are provided at the most important Web sites. Nonetheless, retrieval of single-nucleotide polymorphism (SNP)-related information is not always easy when searches must focus on complementary features. In this work, we present the Bovine SNP Retriever: a user-friendly tool for bovine SNP retrieval that also facilities the retrieval of SNP-related information within user-selected quantitative traits loci regions and reverse electronic polymerase chain reaction analysis on the bovine genome. The Bovine SNP Retriever is available at http://www.itb.cnr.it/ptp/bovine_snp_retriever/.  相似文献   
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The Fe3+ chelating ability of some curcumin glucosyl derivatives (Glc-H; Glc-OH; Glc-OCH3) is tested by means of UV and NMR study. The pK a values of the ligands and the overall stability constants of Fe3+ and Ga3+ complexes are evaluated from UV spectra. The only metal binding site of the ligand is the β-diketo moiety in the keto-enolic form; the glucosyl moiety does not interact with metal ion but it contributes to the stability of metal/ligand 1:2 complexes by means of hydrophilic interactions. These glucosyl derivatives are able to bind Fe3+ in a wide pH rage, forming complex species thermodynamically more stable than those of other ligands commonly used in the treatment of iron deficiency. In addition they demonstrate to have a poor affinity for competitive biological metal ions such as Ca2+. All ligands and their iron complexes have a good lypophilicity (log P > −0.7) suggesting an efficient gastrointestinal absorption in view of their possible use as iron supplements in oral therapy. The ligand molecules are also tested for their antioxidant properties in “ex vivo” biological system.  相似文献   
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The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.  相似文献   
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The cellular prion protein (PrP(C)) is a cell-surface glycoprotein mainly expressed in the CNS. The structural conversion of PrP(C) generates the prion, the infectious agent causing transmissible spongiform encephalopathies, which are rare and fatal diseases affecting animals and humans. Despite decades of intensive research, the mechanism of prion-associated neurodegeneration and the physiologic role of PrP(C) are still obscure. Recent evidence, however, supports the hypothesis that PrP(C) may be involved in the control of Ca(2+) homeostasis. Given the universal significance of Ca(2+) as an intracellular messenger for both the life and death of cells, this possibility may help explain the complex, often controversial, dataset accumulated on PrP(C) physiology, and the events leading to prion-associated neuronal demise. In this study, we have compared local Ca(2+) movements in cerebellar granule neurons (CGN) derived from wild-type (WT), or PrP-knockout (KO), mice, by means of the Ca(2+)-sensitive photo-probe, aequorin, genetically targeted to specific intracellular domains and delivered to CGN by lentiviral vectors. The use of an aequorin that localizes to the cytosolic domains proximal to the plasma membrane has allowed us to demonstrate that there was a dramatic increase of store-operated Ca(2+) entry in PrP-KO CGN compared to WT neurons. Notably, this phenotype was rescued upon restoring PrP(C) expression. The Ca(2+)-phenotype of PrP-KO neurons can in part be explained by the lower expression of two major Ca(2+)-extruding proteins, namely the plasma membrane and the sarco-endoplasmic reticulum Ca(2+)-ATPases. The lower sarco-endoplasmic reticulum Ca(2+)-ATPase content may also contribute to explain why PrP-KO CGN accumulated less Ca(2+) in the endoplasmic reticulum than the WT counterpart.  相似文献   
176.
Warm microemulsions based on lipids characterized by a melting point over 50 degrees C have been successfully used as starting matrix in a quenching process to obtain solid lipid nanoparticles (SLN). In this work, we have investigated the effect of 1-butanol (B) on the phase behavior of the lecithin (LCT)/water (W)/tripalmitin (TP) system at 70 degrees C. The study has been carried out at LCT/B=1 (weight ratio). Emulsion and liquid crystalline phase regions have been observed in the ternary phase diagram, while the presence of 1-butanol in the LCT/W/B/TP system allows the formation of a wide area of liquid isotropic phase from the whole (LCT+B)/TP binary axis up to 37 wt% of water. The microstructure of this isotropic phase has been investigated by means of 1H NMR PGSE technique. The self-diffusion coefficients of the different components along oil and water dilution lines indicate a microstructural organization characterized by a highly connected water in oil domains.  相似文献   
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The simple eyes (ocelli) of recently emerged adult Triatoma infestans exhibit a narrow elongated "pupil", surrounded by a ring of brown-reddish pigment, the "iris". This pupil does not respond to changes in the illumination, but varies in size after the imaginal ecdysis. This change corresponds, internally, with the growth of the corneal lens and the associated retina up to an age of about 20 days. This has not been previously observed in an insect. The use of this characteristic for recognising young adults of this species is suggested.  相似文献   
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