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401.
Rosalba Encarnación Lennart Kenne Gunnar Samuelsson Finn Sandberg 《Phytochemistry》1981,20(8):1939-1942
Four triterpenoid saponins isolated from the stem bark of Lecaniodiscus cupanioides and denoted S-2,S-3,S-4 and S-5, were identified as follows. S-2:3-O-[α-l-arabinopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyl]-hederagenin; S-3:3-O-[α-d-xylopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-l-arabino-pyranosyl ]-hederagenin; S-4:3-O- [α-l-arabinopyranosyl-(1→3)-α-l-rhamnopyranosyl-(1→ 2)-α-l-arabinopyranosyl]-hederagenin; S-5:3-O- [α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranosyl ]-hederagenin. Of these, S-2 and S-4 are new substances. 相似文献
402.
Paolo Mondola Rosalba Seru Simona Damiano Mariarosaria Santillo 《Central European Journal of Biology》2007,2(3):337-350
The CuZn superoxide dismutase (SOD1), a member of a group of isoenzymes involved in the scavenger of superoxide anions, is
a dimeric carbohydrate free protein, mainly localized in the cytosol. The reactive oxygen species (ROS) are involved in many
pathophysiological events correlated with mutagenesis, cancer, degenerative processes and aging. In the first part of this
mini-review the well known role of SOD1 and ROS are briefly summarized. Following, a potential novel biological action that
SOD1 could exert is described, based on the recent researches demonstrating the secretion of this enzyme in many cellular
lines. Moreover, the role of impaired mutant SOD1 secretion, associated with cytoplasmic toxic inclusion, which occurs in
familial amyotrophic lateral sclerosis (ALS), is summarized. In addition, a depolarization-dependent release of SOD1 in pituitary
GH3 cells and in rat synaptosomes through a calcium and SNARE-dependent mechanism is reported. 相似文献
403.
404.
Jonatan Barrera-Chimal Rosalba Pérez-Villalva Juan Antonio Ortega Andrea Sánchez Roxana Rodríguez-Romo Marta Durand Frederic Jaisser Norma A. Bobadilla 《International journal of biological sciences》2015,11(8):892-900
Administration of the mineralocorticoid receptor antagonist spironolactone prevents the development of chronic kidney disease (CKD) after a severe ischemic injury. However, whether brief periods of ischemia lead to CKD and whether spironolactone administration after ischemia may be a useful therapeutic strategy to prevent the gradual deterioration of structure and function remains unexplored.Nineteen male Wistar rats were divided into four groups: rats that underwent renal bilateral ischemia for 10, 20, or 45 min were compared with sham operated rats. Additionally, thirteen male Wistar rats that underwent renal bilateral ischemia for 20 min were divided into an untreated ischemic group (I) and two groups receiving spironolactone, 20 mg/kg by gavage, at either 0 (Sp0) or 1.5-h after ischemia (Sp1.5). The rats were followed up and studied after 9 months.Mild (20 min) and severe (45 min) ischemia induced a progressive increase in proteinuria at varying magnitudes, whereas minor ischemia (10 min) did not modify proteinuria. CKD induced by moderate ischemia was characterized by renal hypertrophy and tubulointerstitial fibrosis. These effects were associated with activation of the transforming growth factor β (TGFβ) signaling pathway and up-regulation of endothelin receptor A (ETA) and alpha smooth muscle actin (αSMA). Spironolactone treatment immediately or 1.5-h after the ischemic insult prevented the onset of these disorders.Our results show that moderate ischemic insult leads to long-term structural and molecular changes that may compromise renal function in later stages. Additionally, we demonstrate that spironolactone administration after mild ischemia prevents this detrimental effect. 相似文献
405.
Murray Goodman Alvin Steinfeld Alan Tonelli Ugo Lepore Manlio Palumbo Bernard Donzel 《Bioorganic chemistry》1974,3(2):184-203
The synthesis of the cyclo-hexadepsipeptide [l-valyl-d-hexahydromandelyl]3 is described. Examination of this macrocyclic compound by 220-MHz nuclear magnetic resonance spectroscopy shows that symmetrical conformations are stabilized in strongly polar solvents (trifluoroacetic acid, acetonitrile), whereas asymmetric conformations are preferred in nonpolar or slightly polar media such as carbon tetrachloride, chloroform, cyclohexane, and benzene.From analysis of the temperature dependence of the chemical shift and of the coupling constants, together with conformational energy calculations, a model is proposed for the preferred conformation of this molecule in nonpolar solvents. 相似文献
406.
Rosalba M. Farnesi Marinella Marinelli Simonetta Tei Daniela Vagnetti 《Journal of morphology》1982,173(2):237-245
The surface receptors in Branchiobdella pentodonta consist of “sense buttons” prevalent on the prostomium, isolated sense cells all along the body of the animal, and free nerve endings. The “sense buttons” are uni- and multiciliated neurosensitive elements and supporting cells together with mucus glandular processes and muscle fibers. In the neurosensitive elements the cilia are always surrounded by cytoplasmic extroversion. The cytoplasm of the apical zone has abundant small dense granules, mitochondria, bands of tonofilaments, and microtubules. The cilium of uniciliated elements originates from three short roots. The highly vacuolated support cells surround the neurosensitive elements, separating them from each other. The “sense buttons” appear to be mechanoreceptors and chemoreceptors, and the isolated sense cells tactile mechanoreceptors, as are the free nerve endings. The surface receptors are compared with those of other Oligochaeta and Hirudinea. 相似文献
407.
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
408.
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409.
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
410.