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排序方式: 共有202条查询结果,搜索用时 15 毫秒
41.
Rosalba Paesano Enrica Pacifici Samanta Benedetti Francesca Berlutti Alessandra Frioni Antonella Polimeni Piera Valenti 《Biometals》2014,27(5):999-1006
Objective Evaluate the safety and efficacy of bovine lactoferrin (bLf) versus the ferrous sulphate standard intervention in curing iron deficiency (ID) and ID anaemia (IDA) in pregnant women affected by hereditary thrombophilia (HT). Design Interventional study. Setting Secondary-level hospital for complicated pregnancies in Rome, Italy. Population 295 HT pregnant women (≥18 years) suffering from ID/IDA. Methods Women were enrolled in Arm A or B in accordance with their personal choice. In Arm A, 156 women received oral administration of 100 mg of bLf twice a day; in Arm B, 139 women received 520 mg of ferrous sulphate once a day. Therapies lasted until delivery. Main outcome measures Red blood cells, haemoglobin, total serum iron, serum ferritin (haematological parameters) were assayed before and every 30 days during therapy until delivery. Serum IL-6, key factor in inflammatory and iron homeostasis disorders, was detected at enrolment and after therapy at delivery. Possible maternal, foetal, and neonatal adverse effects were assessed. Results Haematological parameters were significantly higher in Arm A than in Arm B pregnant women (P ≤ 0.0001). Serum IL-6 significantly decreased in bLf-treated women and increased in ferrous sulphate-treated women. BLf did not exert any adverse effect. Adverse effects in 16.5 % of ferrous sulphate-treated women were recorded. Arm A women experienced no miscarriage compared to five miscarriages in Arm B women. Conclusions Differently from ferrous sulphate, bLf is safe and effective in curing ID/IDA associated with a consistent decrease of serum IL-6. The absence of miscarriage among bLf-treated women provided an unexpected benefit. Trial registration: ClinicalTrials.gov Identifier NCT01221844. 相似文献
42.
Alessandra Frioni Maria Pia Conte Antimo Cutone Catia Longhi Giovanni Musci Maria Carmela Bonaccorsi di Patti Tiziana Natalizi Massimiliano Marazzato Maria Stefania Lepanto Patrizia Puddu Rosalba Paesano Piera Valenti Francesca Berlutti 《Biometals》2014,27(5):843-856
Conflicting data are reported on pro- or anti-inflammatory activity of bovine lactoferrin (bLf) in different cell models as phagocytes or epithelial cell lines infected by bacteria. Here we evaluated the bLf effect on epithelial models mimicking two human pathologies characterized by inflammation and infection with specific bacterial species. Primary bronchial epithelium from a cystic fibrosis (CF) patient and differentiated intestinal epithelial cells were infected with Pseudomonas aeruginosa LESB58 isolated from a CF patient and Adherent-Invasive Escherichia coli LF82 isolated from a Crohn’s disease patient. Surprisingly, bLf significantly reduced the intracellular bacterial survival, but differently modulated the inflammatory response. These data lead us to hypothesize that bLf differentially acts depending on the epithelial model and infecting pathogen. To verify this hypothesis, we explored whether bLf could modulate ferroportin (Fpn), the only known cellular iron exporter from cells, that, by lowering the intracellular iron level, determines a non permissive environment for intracellular pathogens. Here, for the first time, we describe the bLf ability to up-regulate Fpn protein in infected epithelial models. Our data suggest that the mechanism underlying the bLf modulating activity on inflammatory response in epithelial cells is complex and the bLf involvement in modulating cellular iron homeostasis should be taken into account. 相似文献
43.
Cesarina Giallongo Nunziatina Parrinello Daniele Tibullo Piera La Cava Alessandra Romano Annalisa Chiarenza Ignazio Barbagallo Giuseppe A. Palumbo Fabio Stagno Paolo Vigneri Francesco Di Raimondo 《PloS one》2014,9(7)
Tumor immune tolerance can derive from the recruitment of suppressor cell population, including myeloid derived suppressor cells (MDSCs), able to inhibit T cells activity. We identified a significantly expanded MDSCs population in chronic myeloid leukemia (CML) patients at diagnosis that decreased to normal levels after imatinib therapy. In addition, expression of arginase 1 (Arg1) that depletes microenvironment of arginine, an essential aminoacid for T cell function, resulted in an increase in patients at diagnosis. Purified CML CD11b+CD33+CD14-HLADR- cells markedly suppressed normal donor T cell proliferation in vitro. Comparing CML Gr-MDSCs to autologous polymorphonuclear leukocytes (PMNs) we observed a higher Arg1 expression and activity in PMNs, together with an inhibitory effect on T cells in vitro. Our data indicate that CML cells create an immuno-tolerant environment associated to MDSCs expansion with immunosuppressive capacity mediated by Arg1. In addition, we demonstrated for the first time also an immunosuppressive activity of CML PMNs, suggesting a strong potential immune escape mechanism created by CML cells, which control the anti-tumor reactive T cells. MDSCs should be monitored in imatinib discontinuation trials to understand their importance in relapsing patients. 相似文献
44.
Wanzhen Liu David A. S. Smith Gayatri Raina Rowan Stanforth Ivy Ng'Iru Piera Ireri Dino J. Martins Ian J. Gordon Simon H. Martin 《Biology letters》2022,18(6)
Warning coloration provides a textbook example of natural selection, but the frequent observation of polymorphism in aposematic species presents an evolutionary puzzle. We investigated biogeography and polymorphism of warning patterns in the widespread butterfly Danaus chrysippus using records from citizen science (n = 5467), museums (n = 8864) and fieldwork (n = 2586). We find that polymorphism in three traits controlled by known mendelian loci is extensive. Broad allele frequency clines, hundreds of kilometres wide, suggest a balance between long-range dispersal and predation of unfamiliar morphs. Mismatched clines for the white hindwing and forewing tip in East Africa are consistent with a previous finding that the black wingtip allele has spread recently in the region through hitchhiking with a heritable endosymbiont. Light/dark background coloration shows more extensive polymorphism. The darker genotype is more common in cooler regions, possibly reflecting a trade-off between thermoregulation and predator warning. Overall, our findings show how studying local adaptation at the global scale provides a more complete picture of the evolutionary forces involved. 相似文献
45.
Expression of distinct conformations of free HLA-Cw4 heavy chains in transfected neuroblastoma cells
Anna Marozzi Raffaella Meneveri Claudio De Santis Piera Robbioni Elena Molteni Alberto Beretta Antonio G. Siccardi Enrico Ginelli 《Immunogenetics》1996,43(5):289-295
Epitope mapping of HLA-Cw4 indicates that the two monoclonal antibodies (mAbs) L31 and M38, specific for beta 2-microglobulin
(β2m)-free HLA-C heavy chains, react preferentially with the KYK motif, located in the binding groove (α1 domain). Transfection
of HLA-Cw4 cDNA into a neuroblastoma cell line, which normally expresses negligible HLA class I, resulted in the constitutive
surface expression of molecules displaying different reactivities with the two mAbs. This cellular system was used to determine
whether L31 and M38 recognize distinct conformations of β2m-free HLA-C proteins, and to investigate their mechanism of expression. Interferon-γ greatly enhanced the expression of L31-reactive
free chains, while abolishing that of M38-reactive molecules. The cytokine-induced expression of L31-reactive molecules was
inhibited by anti-sense oligonucleotides specific for β2m mRNA, while constitutive expression of L31-reactive molecules was only partially affected. Exogenous β2m resulted in a reduction of constitutive L31 reactivity, and in a concomitant increase of M38 reactivity. These results indicate
that: 1) at the cell surface, L31 and M38 react with two distinct conformations of HLA-Cw4 β2m-free heavy chains, of which the L31-reactive conformation is the least folded; 2) the expression of both conformers can
be modulated by endogenous or exogenous β2m; and (3) L31-reactive molecules exposed at the cell surface are likely to derive from the dissociation of empty HLA-Cw4/β2m complexes. 相似文献
46.
Phosphorylation of the Casein Kinase II Domain of B-50 (GAP-43) in Rat Cortical Growth Cones 总被引:1,自引:1,他引:0
†Michael A. N. Edgar ‡Piera Pasinelli M. DeWit §Brian Anton †Linda A. Dokas Lucia Pastorino Monica DiLuca Flaminio Cattabeni Willem H. Gispen Pierre N. E. De Graan 《Journal of neurochemistry》1997,69(5):2206-2215
Abstract: Growth-associated phosphoprotein B-50 is a neural protein kinase C (PKC) substrate enriched in nerve growth cones that has been implicated in growth cone plasticity. Here we investigated whether B-50 is a physiological substrate for casein kinase II (CKII) in purified rat cortical growth cone preparations. Using site-specific proteolysis and known modulators of PKC, in combination with immunoprecipitation, mass spectrometry, and phosphoamino acid analysis, we demonstrate that endogenous growth cone B-50 is phosphorylated at multiple sites, on both serine and threonine residues. Consistent with previous reports, stimulation of PKC activity increased the phosphorylation of only those proteolytic fragments containing Ser41 . Under basal conditions, however, phosphorylation was predominantly associated with fragments not containing Ser41 . Mass spectrometry of tryptic digests of B-50, which had been immunoprecipitated from untreated growth cones, revealed that in situ phosphorylation occurs within peptides B-50181–198 and B-5082–98 . These peptides contain the major and minor in vitro CKII phosphosites, respectively. In addition, cyanogen bromide digestion of immunoprecipitated chick B-50 generated a 4-kDa C-terminal B-50 phosphopeptide, confirming that phosphorylation of the CKII domain occurs across evolutionary diverse species. We conclude that B-50 in growth cones is not only a substrate for PKC, but also for CKII. 相似文献
47.
Giuseppina Mazzocchi Ludwig K. Malendowicz Piera Rebuffat Claudia Robba Giuseppe Gottardo Prof. Gastone G. Nussdorfer 《Cell and tissue research》1986,243(2):303-310
Summary Short-term ACTH treatment provoked a decrease in volume of the lipid-droplet compartment in rat zona glomerulosa cells, and a rise in plasma and intracellular concentrations of corticosterone and aldosterone. It enhanced activities of 3-hydroxysteroid dehydrogenase (3HSD), 11-hydroxylase (11OH) and 18-hydroxylase (18OH). Long-term ACTH administration produced a hypertrophy of the zona glomerulosa and its parenchymal cells, a result of the increase in volume of the smooth endoplasmic reticulum and the mitochondrial compartment. The surface area per cell of mitochondrial inner membranes increased; the tubular cristae were transformed into a homogeneous population of vesicles. The plasma and intracellular concentrations of corticosterone further increased, whereas those of aldosterone fell below basal levels (the aldosterone-escape phenomenon). The activities of 3HSD and 11OH were enhanced, that of 180H decreased. Therefore, ACTH stimulates zona glomerulosa growth and transforms parenchymal elements into zona fasciculata celltypes. Cyanoketone nullified acute ACTH effects on plasma and intracellular concentrations of corticosterone and aldosterone, but did not affect the activities of 11OH and 18OH. Chronic ACTH treatment produced similar results, although 18OH activity was not suppressed. The mechanism underlying the aldosterone-escape phenomenon may thus involve a rise in the intracellular concentration of corticosterone, caused by the enhanced synthesis and activation of 3HSD and 11OH. 相似文献
48.
The iron status of 50 patients with Ph'-positive chronic granulocytic leukaemia (CGL) was evaluated at diagnosis by means of bone marrow and blood studies. A decreased or absent iron in semiquantitative estimation on bone marrow smears was observed in 92% of patients, and 88% had a low sideroblast score. In contrast, normal Hb and serum iron concentrations were found in the majority of cases, and only two out of the 50 patients displayed a decreased serum ferritin. To ascertain whether the bone marrow pattern of iron depletion could be due to an expansion of the red cell mass, the latter parameter was measured by isotopic methods in a subgroup of 11 patients. Normal or slightly increased values were obtained in all cases. We conclude that absent or decreased marrow iron is a common feature in the chronic phase of CGL, that generally does not reflect true iron deficiency. Since such a finding is also usual in polycythaemia vera and idiopathic myelofibrosis, it should be included among the features shared by the chronic myeloproliferative disorders. 相似文献
49.
50.
The iron status of 26 patients with essential thrombocythaemia (ET) was evaluated at diagnosis by means of bone marrow iron and blood studies, including serum ferritin determination. Nine patients were males, 17 females, and the mean age was 53 years (range 7-81). A decreased or absent iron level by semiquantitative estimation on bone marrow smears was observed in 77% of patients, and 81% had a low sideroblast score. Such a marrow pattern of iron depletion was equally distributed between both sexes. Contrasting with this, normal Hb, MCV, serum iron and serum ferritin were registered in the majority of cases. According to these results, absent or decreased marrow iron would be a common feature in ET, generally not reflecting true iron deficiency, as it occurs in the remaining chronic myeloproliferative disorders. Thus, in patients in whom ET is suspected, the diagnostic criterion of ruling out iron deficiency would be better served by serum ferritin measurement than by bone marrow iron estimation. 相似文献