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PURPOSE: To examine if excessive in-stent neointimal formation causing a subcritical stenosis may indicate enhanced vascular reactivity in response to injury, thus predicting late cardiovascular events. METHODS: One hundred consecutive patients (64 men; median age 71 years) with high-grade internal carotid artery stenoses (68 asymptomatic, 32 symptomatic) underwent carotid artery stenting (CAS). High-sensitivity C-reactive protein (hs-CRP) was measured before CAS. Patients were monitored with duplex ultrasound for excessive in-stent neointimal formation (flow-compromising lumen diameter reduction >/=50%), critical restenosis (>/=70%), or the occurrence of late major adverse cardiovascular events (MACE) defined as myocardial infarction (MI), stroke, and death occurring later than 30 days poststenting. RESULTS: Over a median 23-month follow-up, excessive neointimal formation was observed in 14 (14%) patients, restenosis in 2 (2%), and 30 late MACE in 25 [25%: 4 MIs, 2 ipsilateral strokes (in the patients with restenosis), 8 contralateral strokes, and 16 cardiovascular deaths]. Cumulative MACE-free survival rates at 6, 12, and 24 months were 92%, 84%, and 77%, respectively. Baseline hs-CRP levels were associated both with neointimal hyperplasia (p=0.024) and MACE (p=0.021). Patients with excessive neointimal formation exhibited a significantly increased adjusted risk for MACE (hazard ratio 3.56, p=0.010). CONCLUSIONS: Excessive in-stent neointimal formation after CAS indicates an increased risk for late MACE, potentially reflecting a state of exaggerated vascular reactivity in response to injury. Inflammation, which is associated both with neointimal hyperplasia and MACE, seems a common characteristic of different vascular pathologies.  相似文献   
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Reversible ligands were attached covalently to membrane-bound acetylcholine receptor from Torpedo marmorata by a method which is generally applicable and does not require the synthesis of specially designed molecules. UV irradiation of the receptor in the presence of [3H]trimethisoquin, [3H]phencyclidine, or [3H]perhydrohistrionicotoxin resulted in the labeling of the binding site(s) for these noncompetitive blockers of the permeability response. The labeling of the delta chain was enhanced by carbamoylcholine, and this increase was blocked by snake alpha-toxins. The effect of carbamoylcholine on [3H]trimethisoquin binding was more pronounced than with the other two noncompetitive blockers; in all instances, the labeling was abolished by unlabeled histrionicotoxin. These three compounds therefore interact with the high-affinity site for noncompetitive blockers. Incorporation of radioactivity also occurred into the alpha chain but either was insensitive to cholinergic effectors or decreased in the presence of carbamoylcholine (or snake alpha-toxin), probably as a result of an interaction with the acetylcholine-binding site. In contrast to the other noncompetitive blockers tested, [3H]chlorpromazine heavily labeled the four receptor polypeptides (alpha, beta, gamma, delta), and this labeling also was enhanced by carbamoylcholine and decreased by histrionicotoxin. These data indicate a contribution of the delta chain to the binding site(s) of several well-characterized noncompetitive blockers and suggest that other receptor polypeptides may also contribute to this binding.  相似文献   
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The cycle inhibiting factors (Cifs) are a family of translocated effector proteins, found in diverse pathogenic bacteria, that interfere with the host cell cycle by catalyzing the deamidation of a specific glutamine residue (Gln40) in NEDD8 and the related protein ubiquitin. This modification prevents recycling of neddylated cullin-RING ligases, leading to stabilization of various cullin-RING ligase targets, and also prevents polyubiquitin chain formation. Here, we report the crystal structures of two Cif/NEDD8 complexes, revealing a conserved molecular interface that defines enzyme/substrate recognition. Mutation of residues forming the interface suggests that shape complementarity, rather than specific individual interactions, is a critical feature for complex formation. We show that Cifs from diverse bacteria bind NEDD8 in vitro and conclude that they will all interact with their substrates in the same way. The "occluding loop" in Cif gates access to Gln40 by forcing a conformational change in the C terminus of NEDD8. We used native PAGE to follow the activity of Cif from the human pathogen Yersinia pseudotuberculosis and selected variants, and the position of Gln40 in the active site has allowed us to propose a catalytic mechanism for these enzymes.  相似文献   
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Lesions of the ventromedial prefrontal cortex can result in a deficient decision-making behavior. So far, most experimental results in the neuropsychological decision-making research have been obtained with gambling tasks. Due to their high complexity, it is difficult to evaluate the underlying processes of the decision-making deficits. The aim of this study was to assess if patients with ventromedial prefrontal damage compared to patients with dorsolateral prefrontal damage and controls show a deficit in an early stage of the decision-making process. Nine patients with ventromedial prefrontal damage, three with dorsolateral prefrontal damage, and eleven healthy controls were tested with a newly developed decision task in which they had to search actively for the information they needed for their decisions. Our results show that patients with ventromedial prefrontal damage compared to the brain-lesioned dorsolateral prefrontal control group and healthy controls searched less for information with regard to risk defusing operators or consequences of their decisions indicating impairment already in the early stage of the decision-making process.  相似文献   
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Objective

To investigate the prevalence of high-risk (HR) and low-risk (LR) human papillomavirus (HPV) in prepuces of boys and men without any HPV related lesions.

Patients and methods

Between 2009 and 2011, a total collective of 250 boys and men were investigated in this prospective study. The samples were subdivided into 3 groups regarding their age, consisting of 125 (50 %) children (0–10 years), 38 (15.2 %) adolescents (11–20 years) and 87 (34.8 %) adults (>20 years). In situ hybridization (ISH) was performed to detect HR and LR virus types within the epithelium, followed by microscopic interpretation and determination between episomal and integrative signal pattern.

Results

Our results revealed high levels of HPV concentration (HR and LR) in all age groups: HR versus LR positivity was seen in 45.5 versus 35 % (children), 60.6 versus 63.6 % (adolescents) and 58.3 versus 48.6 % (adults). The topmost rate of HR (59.8 %)- and LR (50.6 %)-positive probes was found in the group with high estimated sexual activity (>14 years).

Conclusion

Concerning the high prevalence of male HPV infection even in children, indicating non-sexual transmission pathways, inclusion of boys in the vaccination program seems to be required reducing their burden of HPV related disease.  相似文献   
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