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511.
Rosalba Paesano Francesca Berlutti Miriam Pietropaoli Fabrizio Pantanella Enrica Pacifici William Goolsbee Piera Valenti 《Biometals》2010,23(3):411-417
Iron deficiency (ID) and iron deficiency anemia (IDA) are the most common iron disorders throughout the world. ID and IDA,
particularly caused by increased iron requirements during pregnancy, represent a high risk for preterm delivery, fetal growth
retardation, low birth weight, and inferior neonatal health. Oral administration of ferrous sulfate to cure ID and IDA in
pregnancy often fails to increase hematological parameters, causes adverse effects and increases inflammation. Recently, we
have demonstrated safety and efficacy of oral administration of 30% iron saturated bovine lactoferrin (bLf) in pregnant women
suffering from ID and IDA. Oral administration of bLf significantly increases the number of red blood cells, hemoglobin, total
serum iron and serum ferritin already after 30 days of the treatment. The increasing of hematological values by bLf is related
to the decrease of serum IL-6 and the increase of serum hepcidin, detected as prohepcidin, whereas ferrous sulfate increases
IL-6 and fails to increase hematological parameters and prohepcidin. bLf is a more effective and safer alternative than ferrous
sulfate for treating ID and IDA in pregnant women. 相似文献
512.
P Parenti P Ferrari M Ferrandi G M Hanozet G Bianchi 《Biochemical and biophysical research communications》1992,183(1):55-61
The effect of ethylisopropyl-amiloride (EIPA) and phenamil on sodium uptake in renal brush border membrane vesicles from prehypertensive rats of the Milan strain (MHS) and their normotensive controls (MNS) was investigated. In the presence of both a membrane potential and a pH gradient a differential effect of EIPA and phenamil was evidenced between the two rat strains. In the absence of a pH gradient, but in the presence of a membrane potential, EIPA was about two-fold more potent than phenamil in inhibiting sodium transport in both rat strains, excluding the presence of epithelial sodium channels in our BBMV preparations. Taken together these results support the hypothesis that a structurally different Na+/H+ exchanger located on the brush border membrane may be involved in the increased tubular sodium reabsorption observed in vivo in hypertensive rats. 相似文献
513.
Alfredo Ferro Rosalba Giugno Giuseppe Pigola Alfredo Pulvirenti Cinzia Di Pietro Michele Purrello Marco Ragusa 《BMC bioinformatics》2007,8(1):58
Background
Backtranslation is the process of decoding a sequence of amino acids into the corresponding codons. All synthetic gene design systems include a backtranslation module. The degeneracy of the genetic code makes backtranslation potentially ambiguous since most amino acids are encoded by multiple codons. The common approach to overcome this difficulty is based on imitation of codon usage within the target species. 相似文献514.
Luigi Rosa Antimo Cutone Maria Stefania Lepanto Mellani Jinnett Scotti Maria Pia Conte Rosalba Paesano Piera Valenti 《Biometals》2018,31(3):301-312
Human and bovine lactoferrin (hLf and bLf) are multifunctional iron-binding glycoprotein constitutively synthesized and secreted by glandular epithelial cells and by neutrophils following induction. HLf and bLf possess very high similarity of sequence. Therefore, most of the in vitro and in vivo studies are carried out with commercial bLf (cbLf), available in large quantities and recognized by Food and Drug Administration (FDA, USA) as a safe substance. Physico-chemical heterogeneity of different cbLf preparations influences their effectiveness. CbLf iron-saturation affects thermal stability and resistance to proteolysis. Moreover, other metal ions such as Al(III), Cu(II), Mg(II), Mn(II), Zn(II) are chelated by cbLf, even if at lower affinity than Fe(III). Ca(II) is also sequestered by the carboxylate groups of sialic acid present on glycan chains of cbLf thus provoking the release of LPS, contributing to bactericidal activity. Similarly to more than 50% of eukaryotic proteins, cbLf possesses five N-glycosylation sites, also contributing to the resistance to proteolysis and, putatively, to the protection of intestinal mucosa from pathogens. CbLfs possess several functions as anti-microbial, anti-biofilm, anti-adhesive, anti-invasive and anti-inflammatory activities. They are also relevant modulators of iron and inflammatory homeostasis. However, the efficacy of cbLfs in exerting several functions can be erratic mainly depending from integrity, degree of iron and other metal ions saturation, N-glycosylation sites and chains, desialylated forms, Ca(II) sequestration, presence of contaminants and finally the ability to enter inside nucleus. 相似文献
515.
516.
A simple fluorometric method for cAMP: application to studies of brain adenylate cyclase activity 总被引:1,自引:0,他引:1
W Wojcik M Olianas M Parenti S Gentleman N H Neff 《Journal of cyclic nucleotide research》1981,7(1):27-35
A simple fluorometric method for the determination of cAMP is presented. The fluorescent derivative is 1,N6-etheno cyclic 3,5-monophosphate (etheno-cAMP). Maximal formation of this derivative occurs after reacting cAMP with chloroacetaldehyde for 15 minutes at 100 degrees C. Fluorescent derivatives are also produced from compounds which contain a 6-amino purine. The specificity of the method resides in the use of a reverse phase/HPLC system. The derivatization as well as the fluorescent response of etheno-cAMP is linear between 2.5 and 700 picomoles of cAMP. Studies of brain adenylate cyclase by the fluorometric/HPLC method indicated that this method is comparable to the established radioenzymatic method. Thus, the present method provides a simple rapid nonradioactive means for the determination of adenylate cyclase activity. 相似文献