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41.
Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC50s) and IC90s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba.  相似文献   
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We report on a male patient with severe autistic disorder, lack of oral language, and dysmorphic features who carries a rare interstitial microdeletion of 4.96 Mb at chromosome 6q14.1‐q15. The patient also harbors a maternally inherited copy number gain of 1.69 Mb at chromosome Xp22.31, whose pathogenicity is under debate.  相似文献   
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Pathogenic strains of Acanthamoeba genus are the causative agents of fatal granulomatous amoebic encephalitis and a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. In a previous study, Acanthamoeba strains were isolated from nasal swabs collected from healthy individuals in Peru. In the present study, the pathogenic potential of the isolated strains was established based on temperature and osmotolerance assays as well as the secretion rate of extracellular proteases. Based on these experiments, four strains that showed the highest pathogenic potential were selected for sensitivity assays against two molecules (voriconazole and chlorhexidine) which are currently used for the treatment of Acanthamoeba infections. After performing sensitivity and activity assays, it was found that both drugs were active against the tested strains. However, voriconazole showed higher activity against the studied strains compared to chlorhexidine. Therefore, voriconazole should be established as a first-line treatment against Acanthamoeba infections at least in the studied region of Peru.  相似文献   
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Fibroelastotic changes (FEC) and especially elastotic polyps of the gastrointestinal (GI) tract are considered rare benign lesions. They consist of accumulations of elastic fibers within the mucosal, submucosal, or muscular layer, occurring in all parts of the GI tract and often appearing as polyps, but also as diffuse non-polyp-forming deposits. They have been the subject of only a few studies. To explore the clinical and histopathological features of FEC in the GI tract, a series of 162 elastotic lesions was collected within a 2-year period. The clinical data and endoscopic findings were correlated. FEC appeared as polyp-forming lesions of the large intestine in 23 samples (14 %), all other samples concerning histological findings without an identifiable gross mass. Frequently related findings were postinterventional status (9 %), previous irradiation (7 %), and history of GI lymphoma (4 %). Eight samples (5 %) presented endoscopically with lesions justifying surgical intervention. We identified three different histological patterns of FEC, which we have called fibroelastosis, angioelastosis, and elastofibroma. Consistent with previous studies, CD34 immunohistochemical staining (performed on 38 polypoid FEC specimens) showed an increase of CD34-positive mesenchymal cells in 95 % of immunostained samples, suggesting a potential role for CD34-positive mesenchymal cells in the accumulation of elastic fibers. In conclusion, FEC are more common in the GI tract than previously recognized. They often present as a benign polyp. Many accompany other diseases like ulcers and atrophic gastritis or represent a residual finding after an intervention.  相似文献   
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BackgroundEspecially in older people, physicians are faced with the coexistence of type 2 diabetes mellitus (T2DM) and Parkinson's disease (PD). Therefore, this research aimed to compare diabetes endpoints between T2DM with and without PD.MethodsBased on the standardized, multicenter, prospective DPV database, 178,992 T2DM patients (≥40 years) were analyzed. 1579 were diagnosed with PD and/or received specific treatment. Hierarchical multivariable regression models were used for group comparisons; adjusted estimates based on observed marginal frequencies were calculated.ResultsPD patients were significantly older (77.9 vs. 70.0 years; p < 0.0001) and had a longer diabetes duration (10.3 vs. 8.4 years; p < 0.0001). In young PD patients (<50 years), percentage of females was significantly higher compared to age-matched T2DM patients without PD or people of the German population (66.7 vs. 38.1 vs. 49.0%; p < 0.0001, p < 0.02).After demographic adjustment, T2DM patients with PD showed a significantly lower HbA1c (58.0 vs. 60.3 mmol/mol; p < 0.0001), OAD/GLP-1 treatment (41.9 vs. 45.9%; p < 0.01) and frequency of dyslipidemia (62.0 vs. 64.5%; p < 0.05). In contrast, rates of insulin therapy (57.8 vs. 54.8%; p < 0.05), hypertension (73.3 vs. 68.6%; p < 0.001), antihypertensive medication (60.4 vs. 56.1%; p < 0.01), stroke (12.0 vs. 7.3%; p < 0.0001), dementia (9.2 vs. 2.6%; p < 0.0001) and repeated inpatient care (15.7 vs. 12.0%; p < 0.0001) were significantly higher and duration of hospital stay (6.2 vs. 4.7 days; p < 0.0001) was significantly longer in T2DM with PD.ConclusionClear demographic and clinical differences were observed between T2DM with and without PD. In PD patients, metabolic control is better, potentially due to more intensive medical care.  相似文献   
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