927 resultados para Fator de necrose tumoral alfa
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Background To perform a comprehensive study on the relationship between vitamin D metabolism and the response to interferon-α-based therapy of chronic hepatitis C. Methodology/Principal Findings Associations between a functionally relevant polymorphism in the gene encoding the vitamin D 1α-hydroxylase (CYP27B1-1260 rs10877012) and the response to treatment with pegylated interferon-α (PEG-IFN-α) and ribavirin were determined in 701 patients with chronic hepatitis C. In addition, associations between serum concentrations of 25-hydroxyvitamin D3 (25[OH]D3) and treatment outcome were analysed. CYP27B1-1260 rs10877012 was found to be an independent predictor of sustained virologic response (SVR) in patients with poor-response IL28B genotypes (15% difference in SVR for rs10877012 genotype AA vs. CC, p = 0.02, OR = 1.52, 95% CI = 1.061–2.188), but not in patients with favourable IL28B genotype. Patients with chronic hepatitis C showed a high prevalence of vitamin D insufficiency (25[OH]D3<20 ng/mL) during all seasons, but 25(OH)D3 serum levels were not associated with treatment outcome. Conclusions/Significance Our study suggests a role of bioactive vitamin D (1,25[OH]2D3, calcitriol) in the response to treatment of chronic hepatitis C. However, serum concentration of the calcitriol precursor 25(OH)D3 is not a suitable predictor of treatment outcome.
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We aimed to examine different intratumoral changes after single-dose and fractionated radiotherapy, using diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) MRI in a rat rhabdomyosarcoma model. Four WAG/Rij rats with rhabdomyosarcomas in the flanks received single-dose radiotherapy of 8 Gy, and four others underwent fractionated radiotherapy (five times 3 Gy). In rats receiving single-dose radiotherapy, a significant perfusion decrease was found in the first 2 days post-treatment, with slow recuperation afterwards. No substantial diffusion changes could be seen; tumor growth delay was 12 days. The rats undergoing fractionated radiotherapy showed a similar perfusion decrease early after the treatment. However, a very strong increase in apparent diffusion coefficient occurred in the first 10 days; growth delay was 18 days. DW-MRI and DCE-MRI can be used to show early tumoral changes induced by radiotherapy. Single-dose and fractionated radiotherapy induce an immediate perfusion effect, while the latter induces more intratumoral necrosis.
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BACKGROUND Nebulized surfactant therapy has been proposed as an alternative method of surfactant administration. The use of a perforated vibrating membrane nebulizer provides a variety of advantages over conventional nebulizers. We investigated the molecular structure and integrity of poractant alfa pre- and post-nebulization. METHOD Curosurf® was nebulized using an Investigational eFlow® Nebulizer System. Non-nebulized surfactant ("NN"), recollected surfactant droplets from nebulization through an endotracheal tube ("NT") and nebulization of surfactant directly onto a surface ("ND") were investigated by transmission electron microscopy. Biophysical characteristics were assessed by the Langmuir-Wilhelmy balance and the Captive Bubble Surfactometer. RESULTS Volume densities of lamellar body-like forms (LBL) and multi-lamellar forms (ML) were high for "NN" and "NT" samples (38.8% vs. 47.7% for LBL and 58.2% vs. 47.8% for ML). In the "ND" sample, we found virtually no LBL's, ML's (72.6%) as well as uni-lamellar forms (16.4%) and a new structure, the "garland-like" forms (9.4%). Surface tension for "NN" and "NT" was 23.33 ± 0.29 and 25.77 ± 1.12 mN/m, respectively. Dynamic compression-expansion cycling minimum surface tensions were between 0.91 and 1.77 mN/m. CONCLUSION The similarity of surfactant characteristics of nebulized surfactant via a tube and the non-nebulized surfactant suggests that vibrating membrane nebulizers are suitable for surfactant nebulization. Alterations in surfactant morphology and characteristics after nebulization were transient. A new structural subtype of surfactant was identified. Pediatr Pulmonol. 2014; 49:348-356. © 2013 Wiley Periodicals, Inc.
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Enzyme replacement therapy (ERT) with recombinant human alglucosidase alfa (rhGAA) in late-onset Pompe disease is moderately effective. Little is known about the clinical course after treatment termination and the resumption of ERT. In Switzerland, rhGAA therapy for Pompe disease was temporarily withdrawn after the federal court judged that the treatment costs were greatly out of proportion compared to the benefits. Re-treatment was initiated after the therapy was finally licensed. We retrospectively analysed seven Pompe patients, who underwent cessation and resumption of ERT (median age 43 years). The delay from first symptoms to final diagnosis ranged from 4 to 20 years. The demographics, clinical characteristics, assessments with the 6-min walking test (6-MWT), the predicted forced vital capacity (FVC) and muscle strength were analysed. Before initiation of ERT, all patients suffered from proximal muscle weakness of the lower limbs; one was wheelchair-bound and two patients received night-time non-invasive ventilation. Initial treatment stabilised respiratory function in most patients and improved their walking performance. After treatment cessation, upright FVC declined in most and the 6-MWT declined in all patients. Two patients needed additional non-invasive ventilatory support. Twelve months after resuming ERT, the respiratory and walking capacity improved again in most patients. However, aside for one patient, none of the patients reached the same level of respiratory function or distance walked in 6 min, as at the time of ERT withdrawal. We conclude that cessation of ERT in Pompe disease causes a decline in clinical function and should be avoided. Resuming treatment only partially recovers respiratory function and walking capacity.
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Übersetzung d. Hauptsachtitels, orientiert an Freimann-Kat.: Katalog der im Lehrhaus Ez Chajim der sefardischen Gemeinde in Amsterdam befindlichen Bücher
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Microbeam radiation therapy (MRT) is a new form of preclinical radiotherapy using quasi-parallel arrays of synchrotron X-ray microbeams. While the deposition of several hundred Grays in the microbeam paths, the normal brain tissues presents a high tolerance which is accompanied by the permanence of apparently normal vessels. Conversely, the efficiency of MRT on tumor growth control is thought to be related to a preferential damaging of tumor blood vessels. The high resistance of the healthy vascular network was demonstrated in different animal models by in vivo biphoton microscopy, magnetic resonance imaging, and histological studies. While a transient increase in permeability was shown, the structure of the vessels remained intact. The use of a chick chorioallantoic membrane at different stages of development showed that the damages induced by microbeams depend on vessel maturation. In vivo and ultrastructural observations showed negligible effects of microbeams on the mature vasculature at late stages of development; nevertheless a complete destruction of the immature capillary plexus was found in the microbeam paths. The use of MRT in rodent models revealed a preferential effect on tumor vessels. Although no major modification was observed in the vasculature of normal brain tissue, tumors showed a denudation of capillaries accompanied by transient increased permeability followed by reduced tumor perfusion and finally, a decrease in number of tumor vessels. Thus, MRT is a very promising treatment strategy with pronounced tumor control effects most likely based on the anti-vascular effects of MRT.
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Scan von Monochrom-Mikroform
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Jakob Pinkerfeld
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Scan von Monochrom-Mikroform
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Scan von Monochrom-Mikroform
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Scan von Monochrom-Mikroform