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Mario Lapecorella Assunta Orecchioni Luigi Dell'Orso Guglielmo Mariani 《Blood coagulation & fibrinolysis》2007,18(5):513-517
The intake of steroid hormone contraceptives is a strong and independent risk factor for venous thromboembolism. Several studies have assessed an increased risk of venous thromboembolism in women using oral contraceptives who are carriers of the G20210A mutation in the prothrombin gene. Most trials evaluating the thrombotic risk of oral contraceptives are based on combined oral preparations, but only a few focus on progestogen-only oral preparations. Results from such studies are conflicting and globally assess the thrombotic risk, ranging from modest to slightly increased. Furthermore, little is known about the relationship between the C677T mutation in the methylenetetrahydrofolate reductase gene and the progestogen-based preparations. Herewith we report the case of a 49-year-old woman with a complex genetic thrombosis risk factor who had taken oral progesterone for 15 months without any complication, but then experienced severe left upper extremity deep vein thrombosis 2 months after the drug suspension. 相似文献
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Di Biase AM Pietrantoni A Tinari A Siciliano R Valenti P Antonini G Seganti L Superti F 《Journal of medical virology》2003,69(4):495-502
Lactoferrin, a member of the transferrin family of approximately 80 kDa, consists of a single polypeptide chain folded in two symmetric, globular lobes (N- and C-lobes), each able to bind one ferric ion. This glycoprotein, found in physiological fluids of mammals, plays an important role in immune regulation and in defense mechanisms against bacteria, fungi, parasites, and viruses. Although the antiviral activity of lactoferrin is one of the major biological functions of such protein, the mechanism of action is still under debate. We have investigated both the role of tryptic fragments of bovine lactoferrin and the mechanism of lactoferrin antiviral effect toward adenovirus infection in HEp-2 cells. The results obtained demonstrated that the anti-adenovirus activity of lactoferrin is mediated by the N-terminal half of the protein as the N-lobe was able to inhibit adenovirus infection, even if at lower extent than undigested lactoferrin, whereas C-lobe was ineffective. The results also showed that the anti-adenovirus action of lactoferrin and of its N-terminal peptide lactoferricin took place on virus attachment to cell membrane, mainly through competition for common glycosaminoglycan receptors. The data provide evidence that the anti-adenovirus activity of lactoferrin is mediated mainly by the cluster of positive charges at the N-terminus of whole molecule and that the N-terminal peptide lactoferricin alone is sufficient to prevent infection. 相似文献
4.
Anti-MOG autoantibodies in Italian multiple sclerosis patients: specificity, sensitivity and clinical association 总被引:2,自引:0,他引:2
Mantegazza R Cristaldini P Bernasconi P Baggi F Pedotti R Piccini I Mascoli N La Mantia L Antozzi C Simoncini O Cornelio F Milanese C 《International immunology》2004,16(4):559-565
There is considerable evidence that multiple sclerosis (MS) is an immune-mediated disease characterized by infiltration of inflammatory cells into the CNS and demyelination. Several myelin proteins may be encephalitogenic, including myelin basic protein, proteolipid protein and myelin oligodendrocyte glycoprotein (MOG), the latter being expressed on the external layer of myelin sheaths and hence accessible to antibody attack. We investigated MOG autoreactivity in serum and cerebrospinal fluid (CSF) by ELISA, employing the recombinant extracellular domain of MOG as antigen. We tested serum samples from 262 MS patients (175 relapsing-remitting, 43 primary progressive and 44 secondary progressive), 131 patients with other neurological diseases (OND) and 307 healthy controls. No patients or controls were receiving immunomodulating treatments. We found anti-MOG antibodies in the serum of 13.7% MS patients, mainly in those with secondary progressive MS (25%), in 13.7% of OND patients and in 6.2% of controls. We found a direct correlation (R(2) = 0.6, P = 0.002) between disease severity and anti-MOG titer only in patients with primary and secondary progressive MS. Anti-MOG antibodies were present in the CSF of 11.4% MS patients and 18.9% OND patients. Intrathecal synthesis of anti-MOG antibodies was demonstrated in four (4.5%) of MS patients and no OND patients. Anti-MOG antibodies are not specific for MS; however, they may characterize a subset of MS patients and this may be revealed by serial assays in relation to changing disease phase. 相似文献
5.
Scali C Prosperi C Bracco L Piccini C Baronti R Ginestroni A Sorbi S Pepeu G Casamenti F 《Neurobiology of aging》2002,23(4):523-530
To evaluate whether inflammation-like mechanisms present in the brain of Alzheimer's disease (AD) patients are reflected in the periphery, the expression of CD11b in peripheral blood neutrophils and the expression and activity of inflammatory markers in cultured skin fibroblasts were examined. We found significantly higher levels of CD11b in neutrophils from sporadic AD patients than in controls and this elevation was positively correlated with disease severity and progression rate of mental decline. Cultured skin fibroblasts from familial (FAD) and sporadic AD patients and from controls were immunopositive for both isoforms of cyclooxygenase with no differences between groups. In unstimulated culture, the production of prostaglandin-E2 in the medium was significantly higher in fibroblasts from sporadic AD and FAD patients than in controls, and this elevation was reverted by the addition of 25 microM of ibuprofen. Our findings provide further evidence of the presence of inflammatory and immuno-related markers in the periphery of AD patients and support those studies indicating the beneficial effects of anti-inflammatory therapy in AD. 相似文献
6.
Carta MG Serra P Ghiani A Manca E Hardoy MC Del Giacco GS Diaz G Carpiniello B Manconi PE 《Psychotherapy and psychosomatics》2002,71(4):233-236
BACKGROUND: People with Down's syndrome (DS) show early Alzheimer-like dementia. It has been suggested that the pro-inflammatory cytokine class plays a role in Alzheimer's disease (AD). The study aims at verifying whether pro-inflammatory cytokines in DS are correlated with age, affective symptoms and intellectual decline to a different degree than in subjects with non-DS learning disabilities. METHODS: Cases: 19 subjects with DS; controls: sex- and age-matched individuals with learning disabilities caused by perinatal ischaemic damage. The level of mental retardation was assessed according to DSM-IV; psychopathological symptoms were measured by the Assessment and Information Rating Profile. Serum levels of cytokines were determined with ELISA. RESULTS: DS patients showed higher levels of cytokines and chemokines, with the exception of RANTES; but the only significant difference detected was for MIP-1alpha. A correlation between the degree of mental retardation and IL-6, and between MIP-lalpha and age was found in patients with DS, but not in controls. CONCLUSIONS: The data obtained suggest a possible involvement of chemokines in the inflammatory and degenerative processes similar to AD in DS. Further longitudinal research is required to confirm these findings. 相似文献
7.
Distribution of, and immune response to, chicken anti-alpha Gal immunoglobulin Y antibodies in wild-type and alpha Gal knockout mice 下载免费PDF全文
Walsh WE Anderson BE Ivancic D Zhang Z Piccini JP Rodgers TG Pao W Fryer JP 《Immunology》2000,101(4):467-473
Chicken antibodies (immunoglobulin Y; IgY) to the alpha Gal epitope (galactose alpha-1,3-galactose) bind to alpha Gal antigens of mouse and porcine tissues and endothelial cells in vitro and block human anti-alpha Gal antibody binding, complement activation and antibody-dependent cell-mediated lysis mechanisms. The activities and toxicity of anti-alpha Gal IgY have not been tested in vivo. In this study, we tested the effects of multiple injections of affinity-purified anti-alpha Gal IgY (AP-IgY) in both wild-type (WT) and alpha-1,3-galactosyltransferase knockout (Gal KO) mice. WT and Gal KO mice were injected once, twice, three, or four times intravenously (i.v.) with AP-IgY and killed at 1 hr or 24 hr. Mice displayed no toxicity to four injections of AP-IgY. Heart, lung, liver, kidney, spleen and pancreatic tissue were evaluated using immunohistochemical techniques for the presence of the alpha Gal epitope using the GSI-B4 lectin, and for bound IgY, as well as mouse IgM and IgG. The binding of AP-IgY antibodies to the endothelium of WT mouse tissues was essentially identical to the pattern of binding of the GSI-B4 lectin after injection of WT mice and death at 1 hr. WT mice killed 24 hr after i.v. injection of AP-IgY showed little remaining bound IgY in their endothelia, indicating that IgY is cleared over that time period. We also evaluated the blood drawn at the time of death for the presence of anti-alpha Gal IgY, anti-IgY IgM and anti-IgY IgG by enzyme-linked immunosorbent assay. Anti-alpha Gal IgY was almost undetectable in WT mouse sera at all injection and killing times. In contrast, Gal KO mouse sera showed increasing anti-alpha Gal IgY levels until 24 hr after the fourth injection, when anti-alpha Gal IgY levels were almost undetectable. Anti-IgY IgM and IgG levels in WT and Gal KO mouse sera showed a typical increase in anti-IgY IgM 24 hr after the second injection (3 days after the first injection) and an increase in anti-IgY IgG 24 hr after the third injection (5 days after the first injection). These results show that IgY binds to alpha Gal epitopes in the WT mice and is cleared sometime over a 24-hr time period and that IgY is an expected immunogen in mice eliciting a rather typical anti-IgY IgM and IgG response. 相似文献
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