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Predictability and prognosis of PTCA-induced coronary artery aneurysms   总被引:9,自引:0,他引:9  
The natural history of coronary aneurysms, defined as local dilatations exceeding the diameter of the normal adjacent vessel segments by at least 1.5 times, is not significantly different from the natural history of nonaneurysmal coronary disease. However, little is known about the prognosis of percutaneous transluminal coronary angioplasty (PCTA)-induced coronary aneurysms. Therefore, we investigated the occurrence and the medium long-term prognosis of such aneurysms in 728 patients who, after successful PTCA, underwent repeat coronary angiography at mean 4.5 months post-PTCA. A coronary aneurysm at the site of PTCA ws noted in 3.9% of patients (n = 28). Of the potentially predictive factors analyzed, only a coronary dissection at the time of PTCA had statistically significant influence. The long-term prognosis of PTCA-induced coronary aneurysms was excellent. One patient underwent (unrelated) cardiac surgery, all other 27 patients remained eventfree. We conclude that the same benign nature of coronary aneurysmal disease holds true for those aneurysms that develop after PTCA.  相似文献   
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Streptogramins are potent drugs against numerous highly resistant pathogens and therefore are used as antibiotics of last-resort human therapy. They consist of a mixture of two different types of chemical substances – the group A streptogramins, which are polyunsaturated macrolactones, and the group B streptogramins, representing cyclic hexadepsipeptides. Streptogramins are unique in their mode of action: each component alone exhibits a moderate bacteriostatic activity by binding to the bacterial 50S ribosomal subunit and thereby blocking translation, whereas the synergic combination of both substances is up to hundred fold more effective than the single compounds, resulting in a bactericidal activity. The streptogramin biosynthetic genes are organized as large antibiotic superclusters. These clusters harbour numerous regulatory genes, which encode different types of regulators that together form a complex hierarchical signalling system, which governs the regulation of streptogramin biosynthesis. Resistance is also regulated by this cascade. However, whereas resistance against streptogramins is quite well understood in diverse pathogenic organisms, only little is known about how the natural producer strains protect themselves against these toxic compounds.  相似文献   
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Stenting for restenotic lesions with the BARD XT stent   总被引:1,自引:0,他引:1  
BACKGROUND: Conventional PTCA for the treatment of restenotic lesions is associated with a high rate of recurrence (30-50%). Primary stenting decreases the restenosis rate at long-term follow-up. METHODS: One-hundred consecutive patients with restenosis received a Bard XT stent. Follow-up angiography was performed after 6 months. Angiograms were compared by means of computed quantitative analysis. RESULTS: The mean pretreatment reference diameter was 2.88 +/- 0.51 mm. The mean minimal luminal diameter (MLD) increased from 1.09 +/- 0.57 mm to 2.70 +/- 0.44 mm. The percent diameter stenosis decreased from 66 +/- 13% to 15 +/- 10%. The procedural success rate was 99%. At 6 month follow-up repeat angiography was performed in 86 patients. The mean MLD was 1.74 +/- 0.67 mm with a mean diameter stenosis of 41 +/- 20%. Residual anginal complaints were reported in 29% of patients. In-stent restenosis (defined as diameter stenosis of more than 50%) occurred in 18% of the patients. CONCLUSION: Placement of the Bard XT stent in restenotic lesions is feasible, has an excellent short term outcome and yields a favorable result at 6 month follow-up angiography.  相似文献   
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Innes AM, Boycott KM, Puffenberger EG, Redl D, MacDonald IM, Chudley AE, Beaulieu C, Perrier R, Gillan T, Wade A, Parboosingh JS. A founder mutation in BBS2 is responsible for Bardet‐Biedl syndrome in the Hutterite population: utility of SNP arrays in genetically heterogeneous disorders. Bardet‐Biedl syndrome (BBS) is a multisystem genetically heterogeneous disorder, the clinical features of which are largely the consequence of ciliary dysfunction. BBS is typically inherited in an autosomal recessive fashion, and mutations in at least 14 genes have been identified. Here, we report the identification of a founder mutation in the BBS2 gene as the cause for the increased incidence of this developmental disorder in the Hutterite population. To ascertain the Hutterite BBS locus, we performed a genome‐wide single nucleotide polymorphism (SNP) analysis on a single patient and his three unaffected siblings from a Hutterite family. The analysis identified two large SNP blocks that were homozygous in the patient but not in his unaffected siblings, one of these regions contained the BBS2 gene. Sequence analysis and subsequent RNA studies identified and confirmed a novel splice site mutation, c.472‐2A>G, in BBS2. This mutation was also found in homozygous form in three subsequently studied Hutterite BBS patients from two different leuts, confirming that this is a founder mutation in the Hutterite population. Further studies are required to determine the frequency of this mutation and its role, if any, in the expression of other ciliopathies in this population.  相似文献   
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Insomnia symptoms are highly prevalent in depressed older adults. This study investigates the association between hypothalamic–pituitary–adrenal (HPA) axis activity and symptoms of insomnia, respectively, sleep duration among 294 depressed and 123 non‐depressed older adults of the Netherlands Study of Depression in Older people (NESDO) study. Insomnia symptoms were defined as clinically relevant when having a score ≥ 10 points on the Women's Health Initiative Insomnia Rating Scale (WHIIRS). Sleep duration was categorized in short (≤ 6 h per night), normal (7–8 h per night) and long (≥ 9 h per night) duration. Salivary cortisol levels were used to assess the following cortisol parameters for HPA axis activity: area under the curve with respect to the increase (AUCi) and to the ground (AUCg), diurnal slope, evening cortisol level and dexamethasone suppression ratio. Clinically relevant insomnia symptoms were present in 46% of the participants. Thirty‐two per cent of the participants were short sleepers, whereas 16% were long sleepers. However, univariate analyses showed no differences in any of the HPA axis parameters between people with and without insomnia symptoms or between the three groups with different sleep duration. In addition, no significant interaction was found between a diagnosis of depression or the severity of depressive symptoms and any of the cortisol parameters in relation to insomnia symptoms or sleep duration.  相似文献   
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