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991.
The long pentraxin PTX3 up-regulates tissue factor in activated monocytes: another link between inflammation and clotting activation 总被引:4,自引:0,他引:4
Napoleone E di Santo A Peri G Mantovani A de Gaetano G Donati MB Lorenzet R 《Journal of leukocyte biology》2004,76(1):203-209
Pentraxin-3 (PTX3), an acute-phase protein that belongs to the family of the PTXs, is found elevated in septic shock and increased in patients with acute myocardial infarction. As tissue factor (TF) plays a key role in thrombosis and inflammation associated with atherosclerosis and as we have recently reported that PTX3 increases TF synthesis in endothelial cells, we tested whether PTX3 could modulate TF expression in monocytes. Monocytes from peripheral blood of healthy donors were incubated with highly purified PTX3 with or without lipopolysaccharide (LPS). Cells were then disrupted, and procoagulant activity was assessed by a one-stage clotting time. PTX3 enhanced TF activity and antigen from LPS-stimulated monocytes in a dose-dependent way. The effect was specific, as other PTXs, such as C-reactive protein and serum amyloid P component, were ineffective. Moreover, the increase in activity was specific for LPS, as in the presence of other TF-inducing agents such as interleukin-1beta and tumor necrosis factor alpha, PTX3 was not effective. The increase in TF activity requires mRNA synthesis, as assessed by polymerase chain reaction. The mechanism by which PTX3 modulates TF synthesis resides in an enhanced IkappaB, alpha phosphorylation and degradation and increased migration of the transacting factor c-Rel/p65 into the nucleus, as determined by Western blot and electro-mobility shift assay. These results show that PTX3 is an enhancer of the expression of TF by mononuclear cells. In the area of vascular injury, during the inflammatory response, cell-mediated fibrin deposition takes place. PTX3 increases TF expression, thus potentially playing a role in thrombogenesis and wound healing. 相似文献
992.
Glucocorticoid-induced TNF receptor family gene (GITR) knockout mice exhibit a resistance to splanchnic artery occlusion (SAO) shock 总被引:2,自引:0,他引:2
Cuzzocrea S Nocentini G Di Paola R Mazzon E Ronchetti S Genovese T Muià C Caputi AP Riccardi C 《Journal of leukocyte biology》2004,76(5):933-940
In the present study, we used glucocorticoid-induced tumor necrosis factor (TNF) receptor family gene knockout (GITR-KO) mice to evaluate a possible role of GITR on the pathogenesis of splanchnic artery occlusion (SAO) shock, which was induced in mice by clamping the superior mesenteric artery and the celiac artery for 30 min, followed thereafter by release of the clamp (reperfusion). At 60 min after reperfusion, animals were killed for histological examination and biochemical studies. There was a marked increase in the lipid peroxidation in the ileum of the SAO-shocked, GITR wild-type (WT) mice after reperfusion. The absence of GITR significantly reduced the lipid peroxidation in the intestine. SAO-shocked WT mice developed a significant increase of ileum tissue, TNF-alpha, and myeloperoxidase activity and marked histological injury. SAO shock was also associated with a significant mortality (5% survival at 24 h after reperfusion). Reperfused ileum tissue sections from SAO-shocked WT mice showed positive staining for P-selectin, intercellular adhesion molecule 1 (ICAM-1), and E-selectin. The intensity and degree of P-selectin, E-selectin, and ICAM-1 were markedly reduced in tissue section from SAO-shocked, GITR-KO mice. SAO-shocked, GITR-KO mice also showed a significant reduction of the TNF-alpha production and neutrophil infiltration into the reperfused intestine, an improved histological status of the reperfused tissues, and an improved survival. Taken together, our results clearly demonstrate that GITR plays an important role in the ischemia and reperfusion injury and put forward the hypothesis that modulation of GITR expression may represent a novel and possible strategy. 相似文献
993.
Rolla G Nebiolo F Marsico P Guida G Bigo P Riva G Zanotta S 《International archives of allergy and immunology》2004,135(4):293-295
BACKGROUND: The European tick, Argas reflexus, is an urban pest parasitizing urban pigeons and may cause a wide range of allergic reactions. METHODS: Specific IgE to A. reflexus, SDS-PAGE and IgE immunoblotting, performed with tick extract, were carried out in the sera of 6 patients who reported allergic reactions after tick bite. RESULTS: Specific IgE to A. reflexus (RAST class ranging from 1 to 3) were detected in the sera of 6 patients who reported allergic reactions (urticaria and angioedema in 2 and anaphylaxis in the other 4 patients) after tick bite. IgE reactivity to two bands of 22 and 40 kDa were identified in the patient sera. CONCLUSIONS: Allergy to A. reflexus has to be considered in allergic patients living in buildings where pigeons have their nests. The powerful sensitizing property of tick allergen is underlined by the observation that none of our patients was atopic. 相似文献
994.
Katharine M. Dyne Maurizia Valli Antonella Forlino Monica Mottes Hans Kresse Giuseppe Cetta 《American journal of medical genetics. Part A》1996,63(1):161-166
In osteogenesis imperfecta (OI) the effects of mutations in type I collagen genes generally reflect their nature and localization. Unrelated individuals sharing identical mutations present, in general, similar clinical phenotypes. However, in some such cases the clinical phenotype differs. This variable clinical expression could be the result of abnormalities in other connective tissue proteins. Since decorin is a component of connective tissue, binds to type I collagen fibrils and plays a role in matrix assembly, we studied decorin production in skin fibroblasts from OI patients. Cultured fibroblasts from one patient with extremely severe osteogenesis imperfecta (classified as type II/III) who has an α1(I)gly415ser mutation were found to secrete barely detectable amounts of decorin into culture medium. Western blotting using antibodies raised against decorin confirmed the reduction of the decorin core protein and Northern blot analysis showed decorin mRNA levels below the limit of detection. Cells from a patient, with a less severe phenotype, bearing a mutation in the same position of the triple helix (α1(I)gly415) expressed decorin normally. The different clinical phenotypes could be due to the differing genetic backgrounds of the patients so it is tempting to conclude that in our most severely affected patient the absence of decorin aggravates the clinical phenotype. © 1996 Wiley-Liss, Inc. 相似文献
995.
Enrico Lupia Giuseppe Montrucchio Edda Battaglia Vittorio Modena Giovanni Camussi 《European journal of immunology》1996,26(8):1690-1694
The aim of the present study was to investigate in vivo in a mouse model the stimulation of neoangiogenesis by synovial fluids of patients with rheumatoid arthritis (RA) and to determine the role of tumor necrosis factor (TNF)-α and platelet-activating factor (PAF) in the formation of new vessels. Angiogenesis was studied in a mouse model in which Matrigel, injected subcutaneously, was used as a vehicle for the delivery of potential angiogenic stimuli. Synovial fluids of patients with RA but not with osteoarthritis (OA) were shown to induce neoangiogenesis. Since synovial fluid of patients with RA contained significantly higher levels of TNF-α-like bioactivity and of PAF than that of patients with OA, the role of these mediators was evaluated by using an anti-TNF-α neutralizing monoclonal antibody (mAb) and a PAF receptor antagonist, WEB 2170. When added to Matrigel, anti-TNF-α mAb and particularly WEB 2170 significantly reduced neoangiogenesis induced by synovial fluids of RA patients. Moreover, PAF extracted and purified from synovial fluid induced angiogenesis. These results suggest that the neoangiogenesis observed in rheumatoid synovitis may be due, at least in part, to the angiogenic effect of locally produced TNF-α and PAF. 相似文献
996.
Lubricin, which is a boundary joint lubricant, was investigated immunohistochemically in the bilaminar zone (BZ) of the human temporomandibular joint (TMJ), without any degenerative changes. Immunohistochemistry for lubricin detection was carried out on 33 TMJ discs obtained from 17 cadavers. Sections were incubated with diluted rabbit polyclonal anti-lubricin antibody and scored according to the percentage of lubricin immunopositive cells. Three different TMJ disc tissue compartments were analyzed, namely: the upper lamina, the inferior lamina and the loose connective tissue in the space between the laminae. The Mann-Whitney U test was used to compare protein expression (lubricin) among disc specimens’ regions. Staining was noted within the TMJ disc cell populations in every disc tissue sample, with almost every cell immunolabeled by the lubricin antibody. The number of disc cells immunolabeled was almost the same in the 3 bilaminar zone regions. Positive extracellular matrix staining was also seen. The results of the present study suggest that lubricin is expressed in the TMJ disc bilaminar zone. Lubricin may have a role in normal disc posterior attachment physiology through the prevention of cellular adhesion as well as providing lubrication during normal bilaminar zone function. 相似文献
997.
V Antonaglia M Ferluga G Capitanio U Lucangelo F Piller E Roman-Pognuz B Biancardi GD Caggegi WA Zin 《Respiratory physiology & neurobiology》2012,183(1):35-40
The purpose was to determine if 2 weeks of buspirone suppressed post-hypoxic breathing instability and pauses in the C57BL/6J (B6) mouse. Study groups were vehicle (saline, n=8), low-dose (1.5 mg/kg, n=8), and high-dose buspirone (5.0 mg/kg, n=8). Frequency, measured by plethysmography, was the major metric, and a pause defined by breathing cessation >2.5 times the average frequency. Mice were tested after 16 days of ip injections of vehicle or drug. On day 17, 4 mice in each group were tested after buspirone and the 5-HT(1A) receptor antagonist, 4-iodo-N-{2-[4-(methoxyphenyl)-1-piperazinyl] ethyl}-N-2-pyridinyl-benzamide (p-MPPI, 5 mg/kg). A post-hypoxic pause was present in 6/8 animals given vehicle and 1/16 animals given buspirone at either dose, but always present (8/8) with p-MPPI, regardless of buspirone dose. Post-hypoxic frequency decline was blunted by buspirone (-10% vehicle vs. -5% at both doses) and restored by p-MPPI; ventilatory stability as described by the coefficient of variation which was reduced by buspirone (p<0.04) was increased by p-MPPI (0.01). In conclusion, buspirone administration after 2 weeks acts through the 5-HT(1A) receptor to reduce post-hypoxic ventilatory instability in the B6 strain. 相似文献
998.
Individuals with anorexia nervosa (AN) have a disturbance in the way in which their body is experienced and tend to evaluate negatively their own body and body parts. It is controversial whether these symptoms are secondary to dysfunctions in the neuronal processes related to appetite and emotional regulation or reflect a primary disturbance in the way the body is experienced and remembered. According to the "Allocentric Lock Hypothesis--ALH" (http://dx.doi.org/10.1016/j.mehy.2011.10.039) individuals with AN may be locked to an allocentric (observer view) negative memory of the body that is no more updated by contrasting egocentric representations driven by perception. Recent neuroimaging studies are showing several structural and functional alterations in frame- and memory-related body-image-processing brain circuits that may support ALH. 相似文献
999.
Valetto A Orsini A Bertini V Toschi B Bonuccelli A Simi F Sammartino I Taddeucci G Simi P Saggese G 《European journal of medical genetics》2012,55(5):362-366
We report on a de novo interstitial deletion of chromosome 21q in a patient presenting with characteristic facial features, intellectual disability, and epilepsy. The deletion extent was about 4.9 Mb from position 37713441 bp (21q22.13) to position 42665162 bp (21q22.3) (NCBI36/hg18 map).Patients with partial monosomy 21 are quite rare; this anomaly has been associated with a wide spectrum of clinical signs, ranging from very mild to quite severe phenotypes. This variability results from variability in the deleted regions, thus accurate molecular definition of the chromosomal breakpoints is necessary to make better genotype-phenotype correlations.We compared our patient's phenotype with the few other patients reported in the literature and found to have similar deletion when analyzed by array CGH. The minimal overlapping region contains only two genes, DYRK1A and KCNJ6, which may play a major role in these patients' phenotype. 相似文献
1000.
The ring 14 syndrome is a rare condition, whose precise clinical and genetic characterization is still limited. This review summarizes literature data and it describes our own experience with 27 patients with ring 14 syndrome. Clinically, the ring 14 syndrome is characterized by a recognizable phenotype of shortness of stature, distinctive facial appearance, microcephaly, scoliosis, and ocular abnormalities, consisting mainly of abnormal retinal pigmentation, but also retinitis pigmentosa, strabismus, glaucoma, and abnormal macula. Virtually all patients are intellectually delayed, with aggressive and hyperactive behavior in some. Drug-resistant, mainly focal in type, epilepsy is another highly consistent finding. In our own sample of patients the ring was complete, with no apparent loss of chromosome material, in 6/27 cases, while it showed a small terminal deletion, varying in size from 0.3 to 5 Mb, in the other 21. In two of these a cryptic 14q duplication of 2.5 and 9.7 Mb, respectively, proximal to the deleted segment, was also identified. Deleted rings were 75% paternal and 25% maternal in origin. UPD (14) was excluded in all cases. Based on literature review of linear deletions, affecting either the proximal or the distal 14q region, we could deduce that retinal abnormalities and epilepsy map within the proximal 14q11.2- q12 region. Because this region is preserved in all patients with ring 14, we speculate that genes residing in the proximal 14q interval are disregulated through heterochromatinization spreading from the adjacent short arm of the chromosome. Behavior disorders and susceptibility to infections can be assigned to the 14q32 region, haploinsufficiency being the most likely underlying mechanism. 相似文献