939 resultados para Ferencz, Rákóczy II, Prince of Translyvania, 1676-1735.
Resumo:
In the paper of Bonora et al. (2008) [3] we have shown, in the context of type II superstring theory, the classification of the allowed B-field and A-field configurations in the presence of anomaly-free D-branes, the mathematical framework being provided by the geometry of gerbes. Here we complete the discussion considering in detail the case of a stack of D-branes, carrying a non-abelian gauge theory, which was just sketched in Bonora et al. (2008) [3]. In this case we have to mix the geometry of abelian gerbes, describing the B-field, with the one of higher-rank bundles, ordinary or twisted. We describe in detail the various cases that arise according to such a classification, as we did for a single D-brane, showing under which hypotheses the A-field turns out to be a connection on a canonical gauge bundle. We also generalize to the non-abelian setting the discussion about "gauge bundles with non-integral Chern classes", relating them to twisted bundles with connection. Finally, we analyze the geometrical nature of the Wilson loop for each kind of gauge theory on a D-brane or stack of D-branes.
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Noonan syndrome (NS) and Noonan-related disorders [cardio-facio-cutaneous (CFC), Costello, Noonan syndrome with multiple lentigines (NS-ML), and neurofibromatosis-Noonan syndromes (NFNS)] are a group of developmental disorders caused by mutations in genes of the RAS/MAPK pathway. Mutations in the KRAS gene account for only a small proportion of affected Noonan and CFC syndrome patients that present an intermediate phenotype between these two syndromes, with more frequent and severe intellectual disability in NS and less ectodermal involvement in CFC syndrome, as well as atypical clinical findings such as craniosynostosis. Recently, the first familial case with a novel KRAS mutation was described. We report on a second vertical transmission (a mother and two siblings) with a novel mutation (p.M72L), in which the proband has trigonocephaly and the affected mother and sister, prominent ectodermal involvement. Metopic suture involvement has not been described before, expanding the main different cranial sutures which can be affected in NS and KRAS gene mutations. The gene alteration found in the studied family is in close proximity to the one reported in the other familial case (close to the switch II region of the G-domain), suggesting that this specific region of the gene could have less severe effects on intellectual ability than the other KRAS gene mutations found in NS patients and be less likely to hamper reproductive fitness. (c) 2012 Wiley Periodicals, Inc.
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Diffusely infiltrating gliomas (WHO grade II-IV) are the most common primary brain tumours in adults. These tumours are not amenable to cure by surgery alone, so suitable biomarkers for adjuvant modalities are required to guide therapeutic decision-making. Epigenetic silencing of the O(6)-methylguanine-DNA methyltransferase (MGMT) gene by promoter methylation has been associated with longer survival of patients with high-grade gliomas who receive alkylating chemotherapy; and molecular testing for the methylation status of the MGMT promoter sequence is regarded as among the most relevant of such markers. We have developed a primer extension-based assay adapted to formalin-fixed paraffin-embedded tissues that enables quantitative assessment of the methylation status of the MGMT promoter. The assay is very sensitive, highly reproducible, and provides valid test results in nearly 100% of cases. Our results indicate that oligodendrogliomas, empirically known to have a relatively favourable prognosis, are also the most homogeneous entities in terms of MGMT promoter methylation. Conversely, astrocytomas, which are more prone to spontaneous progression to higher grade malignancy, are significantly more heterogeneous. In addition, we show that the degree of promoter methylation correlates with the prevalence of loss of heterozygosity on chromosome arm 1p in the oligodendroglioma group, but not the astrocytoma group. Our results may have potentially important implications for clinical molecular diagnosis.
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Sphingosine kinase 1 (SK1) is a key enzyme in the generation of sphingosine 1-phosphate (S1P) which critically regulates a variety of important cell responses such as proliferation and migration. Therefore, inhibition of SK-1 has been suggested to be an attractive approach to treat tumor growth and metastasis formation.
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There is no standard treatment for patients with locally advanced esophageal carcinoma without systemic metastasis in whom surgery is no longer considered a reasonable option.
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Isolated GH deficiency type II (IGHD II) is the autosomal dominant form of GHD. In the majority of the cases, this disorder is due to specific GH-1 gene mutations that lead to mRNA missplicing and subsequent loss of exon 3 sequences. When misspliced RNA is translated, it produces a toxic 17.5-kDa GH (Delta3GH) isoform that reduces the accumulation and secretion of wild-type-GH. At present, patients suffering from this type of disease are treated with daily injections of recombinant human GH in order to maintain normal growth. However, this type of replacement therapy does not prevent toxic effects of the Delta3GH mutant on the pituitary gland, which can eventually lead to other hormonal deficiencies. We developed a strategy involving Delta3GH isoform knockdown mediated by expression of a microRNA-30-adapted short hairpin RNA (shRNA) specifically targeting the Delta3GH mRNA of human (shRNAmir-Delta3). Rat pituitary tumor GC cells expressing Delta3GH upon doxycycline induction were transduced with shRNAmir-Delta3 lentiviral vectors, which significantly reduced Delta3GH protein levels and improved human wild-type-GH secretion in comparison with a shRNAmir targeting a scrambled sequence. No toxicity due to shRNAmir expression could be observed in cell proliferation assays. Confocal microscopy strongly suggested that shRNAmir-Delta3 enabled the recovery of GH granule storage and secretory capacity. These viral vectors have shown their ability to stably integrate, express shRNAmir, and rescue IGHD II phenotype in rat pituitary tumor GC cells, a methodology that opens new perspectives for the development of gene therapy to treat IGHD patients.
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Patients with brain metastases (BM) rarely survive longer than 6months and are commonly excluded from clinical trials. We explored two combined modality regimens with novel agents with single agent activity and radiosensitizing properties.
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Carnitine (Car) buffers excess acetyl-CoA through the formation of acetylCar (AcCar). AcCar's acetyl group (AG-AcCar) gives rise to a peak at 2.13 ppm in ¹H MR spectra of skeletal muscle, whereas the trimethylammonium (TMA) groups of both, AcCar and Car, are thought to contribute to the TMA peak at 3.23 ppm. Surprisingly, in previous studies both resonances, AG-AcCar and TMA, increased after exercise. The aim of this study was to assess if the exercise-related TMA increase correlated with AcCar production. Magnetic resonance spectroscopic imaging (pulse repetition time/echo time = 1200/35 ms) was performed before and after prolonged exercise in the lower leg and thigh of eight runners and eight cyclists, respectively. TMA and AG-AcCar increased after exercise (P < 0.001). TMA's increase correlated with the AG-AcCar increase (R² = 0.73, P < 0.001, lower leg; R² = 0.28, P < 0.001, thigh). The correlation of ΔTMA with ΔAG-AcCar suggests that the TMA increase is due to AcCar formation. As total Car (Car + AcCar) remains unchanged with exercise, these findings suggest that the contribution of free Car to the TMA peak is limited and, therefore, is partly invisible in muscle ¹H MR spectra. This indicates that the biochemically relevant cytosolic content of free Car is considerably lower than the overall concentration determined by radioisotopic assays, a potentially important result with respect to regulation of substrate oxidation.
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To determine the response rate to oral capsular fenretinide in children with recurrent or biopsy proven refractory high-risk neuroblastoma.
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Based on current data and experience, the joint working group of the European Society of Minimally Invasive Neurological Therapy (ESMINT) and the European Society of Neuroradiology (ESNR) make suggestions on trial design and conduct aimed to investigate therapeutic effects of mechanical thrombectomy (MT). We anticipate that this roadmap will facilitate the setting up and conduct of successful trials in close collaboration with our neighbouring disciplines.
Resumo:
BACKGROUND: There is an increasing demand for comprehensive forms of palliative cancer care, meeting physical as well as emotional, cognitive, spiritual and social needs. Therapy programs of anthroposophic hospitals are aimed at improving health and quality of life (QoL) at these levels. However, data on the influence of these programs on QoL of patients with advanced cancer are scarce. PATIENTS AND METHODS: 144 in-patients with advanced epithelial cancers were treated at the anthroposophic Lukas Klinik, Arlesheim, Switzerland. QoL was assessed upon admission, discharge and after 4 months, using 20 functional scales from the questionnaires EORTC QLQ-C30, HADS and SELT-M. Statistical testing was performed with the Wilcoxon signed rank test. At month 4, subjectively perceived benefits from anthroposophic medicine (AM) and conventional cancer therapy (CCT) were assessed by telephone. OBJECTIVE: The aim was to provide an account of global, physical, emotional, cognitive-spiritual and social QoL developments in advanced cancer patients, during and after in-patient AM treatment, and to investigate subjective benefits from AM and CCT. RESULTS: QoL improvements were observed in all 20 dimensions (12 significant). Compared to related studies, improvements were fairly high. At month 4, QoL scores had decreased but were still above baseline in all 20 dimensions. Both AM and CCT were perceived as beneficial. CONCLUSION: Our data provide evidence that in-patient therapy at an anthroposophic hospital can lead to significant QoL improvements, especially in emotional, but also global, physical, cognitive-spiritual and social aspects. Benefits of AM were experienced on the physical, emotional, cognitive- spiritual and social level. Benefits of CCT were tumor-focused.
Resumo:
This study investigates whether adaptations of mitochondrial function accompany the improvement of endurance performance capacity observed in well-trained athletes after an intermittent hypoxic training program. Fifteen endurance-trained athletes performed two weekly training sessions on treadmill at the velocity associated with the second ventilatory threshold (VT2) with inspired O2 fraction = 14.5% [hypoxic group (Hyp), n = 8] or with inspired O2 fraction = 21% [normoxic group (Nor), n = 7], integrated into their usual training, for 6 wk. Before and after training, oxygen uptake (VO2) and speed at VT2, maximal VO2 (VO2 max), and time to exhaustion at velocity of VO2 max (minimal speed associated with VO2 max) were measured, and muscle biopsies of vastus lateralis were harvested. Muscle oxidative capacities and sensitivity of mitochondrial respiration to ADP (Km) were evaluated on permeabilized muscle fibers. Time to exhaustion, VO2 at VT2, and VO2 max were significantly improved in Hyp (+42, +8, and +5%, respectively) but not in Nor. No increase in muscle oxidative capacity was obtained with either training protocol. However, mitochondrial regulation shifted to a more oxidative profile in Hyp only as shown by the increased Km for ADP (Nor: before 476 +/- 63, after 524 +/- 62 microM, not significant; Hyp: before 441 +/- 59, after 694 +/- 51 microM, P < 0.05). Thus including hypoxia sessions into the usual training of athletes qualitatively ameliorates mitochondrial function by increasing the respiratory control by creatine, providing a tighter integration between ATP demand and supply.
Resumo:
BACKGROUND: Paclitaxel and capecitabine have proven activity in the treatment of metastatic breast cancer (MBC). Paclitaxel increases the expression of thymidine phosphorylase, the enzyme that activates capecitabine. The purpose of this study was to evaluate the efficacy and tolerability of capecitabine in combination with weekly paclitaxel largely as first-line therapy in patients with MBC. PATIENTS AND METHODS: From April 2002 to September 2004, 19 patients with MBC received oral capecitabine (1,000 mg/m(2) twice daily on days 1-14) plus i.v. paclitaxel (80 mg/m(2) on days 1, 8 and 15) in a 21-day cycle for a maximum of 6 cycles. RESULTS: After a median follow-up of 19.3 months the overall response rate was 63% with 1 complete response (5%) and 11 partial responses (58%). Disease was stabilized in 1 patient (5%) and 3 patients had progressive disease (16%). Three patients were unable to be assessed for response to treatment. Median time to progression was 3.3 months, median time to treatment failure 3.0 months and median overall survival 13.8 months. A substantial number of patients experienced major side effects. The most common treatment-related adverse events were hand-foot syndrome (53%; grade 3: 37%), alopecia (42%; grade 3: 26%), diarrhea (32%; grade 3: 11%) and neurotoxicity (32%; grade 3: 16%). Hematologic toxicities were uncommon. CONCLUSION: The combination of capecitabine and paclitaxel appears to be active in MBC but the safety profile with the dosages used in this trial was unacceptably high and led to a short time to treatment failure. However, based on the efficacy data alternative schedules deserve further evaluation.
Resumo:
This randomized phase II trial evaluated two docetaxel-based regimens to see which would be most promising according to overall response rate (ORR) for comparison in a phase III trial with epirubicin-cisplatin-fluorouracil (ECF) as first-line advanced gastric cancer therapy.