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91.

Objectives

Glioblastoma (GBM) is the most common malignant primary brain tumour in adults. Surgery and radiotherapy constitute the cornerstones for the therapeutic management of GBM. The standard treatment today is maximal surgical resection followed by concomitant chemo-radiation therapy followed by adjuvant TMZ according to Stupp protocol. Despite the progress in neurosurgery, radiotherapy and oncology, the prognosis still results poor.In order to reduce the long time of standard treatment, maintaining or improving the clinical results, in our institute we have investigated the effects of hypo-fractionated radiation therapy for patients with GBM.

Patients and methods

Sixty-seven patients affected by GBM who had previously undergone surgical resection (total, subtotal or biopsy) were enrolled between October 2005 and December 2011 in a single institutional study of hypo-fractionated intensity modulated radiation therapy (IMRT) followed or not by adjuvant chemotherapy with TMZ (6–12 cycles). The most important eligibility criteria were: biopsy-proven GBM, KPS ≥ 60, age ≥ 18 years, no previous brain irradiation, informed consensus. Hypo-fractionated IMRT was delivered to a total dose of 25 Gy in 5 fractions prescribed to 70% isodose. Response to treatment, OS, PFS, toxicity and patterns of recurrence were evaluated, and sex, age, type of surgery, Karnofsky performance status, Recursive Partitioning Analysis (RPA) classification, time between surgery and initiation of radiotherapy were evaluated as potential prognostic factors for survival.

Results

All patients have completed the treatment protocol. Median age was 64.5 years (range 41–82 years) with 31 females (46%) and 36 males (54%). Median KPS at time of treatment was 80. The surgery was gross total in 38 patients and subtotal in 14 patients; 15 patients underwent only biopsy.No grade 3–4 acute or late neurotoxicity was observed. With median follow-up of 14.9 months, the median OS and PFS were 13.4 and 7.9 months, respectively.

Conclusions

The hypo-fractionated radiation therapy can be used for patients with GBM, resulting in favourable overall survival, low rates of toxicity and satisfying QoL. Future investigations are needed to determine the optimal fractionation for GBM.  相似文献   
92.

Background

Fundoplication is considered a mainstay in the treatment of gastro-esophageal reflux. However, the literature reports significant recurrences and limited data on long-term outcome.

Aims

To evaluate our long-term outcomes of antireflux surgery in children and to assess the results of redo surgery.

Methods

We retrospectively analyzed all patients who underwent Nissen fundoplication in 8 consecutive years. Reiterative surgery was indicated only in case of symptoms and anatomical alterations. A follow-up study was carried out to analyzed outcome and patients’ Visick score assessed parents’ perspective.

Results

Overall 162 children were included for 179 procedures in total. Median age at first intervention was 43 months. Comorbidities were 119 (73 %), particularly neurological impairments (73 %). Redo surgery is equal to 14 % (25/179). Comorbidities were risk factors to Nissen failure (p = 0.04), especially children suffering neurological impairment with seizures (p = 0.034). Follow-up datasets were obtained for 111/162 = 69 % (median time: 51 months). Parents’ perspectives were excellent or good in 85 %.

Conclusions

A significant positive impact of redo Nissen intervention on the patient’s outcome was highlighted; antireflux surgery is useful and advantageous in children and their caregivers. Children with neurological impairment affected by seizures represent significant risk factors.
  相似文献   
93.
The 5-lipoxygenase (5-LO) pathway of arachidonic acid metabolism is an important source of inflammatory mediators, and is also present in the central nervous system. In this study, we assayed the expression levels and activity of 5-LO in different brain regions of young versus old C57Bl/6 mice. 5-LO mRNA was expressed in all the brain regions considered, i.e. cortex, hippocampus, and cerebellum. The highest expression level was observed in cerebellum compared with cortex and hippocampus, although it was not affected by aging. By contrast, 5-LO mRNA and protein levels were significantly increased in the hippocampus of old (25 months) versus young (3 months) mice. Finally, levels of the leukotriene B4, a metabolic product of 5-LO, were significantly increased in the hippocampus of old mice, but no difference was observed in cortex and cerebellum. These results demonstrate that the 5-LO enzymatic pathway is widely expressed in the mouse CNS, where significant changes are region-specific and age-dependent. This observation supports the hypothesis that 5-LO may be involved in diseases of the brain associated with aging.  相似文献   
94.
Rearrangement of the BCL6 gene is found in follicular lymphomas and in diffuse large B cell lymphomas of follicular center cell origin. The breakpoints cluster mainly in a region spanning the first noncoding exon of the gene (the major breakpoint region). A second breakpoint cluster has also been identified upstream of the first BCL6 noncoding exon (the alternative breakpoint region [ABR]). To date, eight different rearrangements involving the ABR have been reported. Here, we describe a novel rearrangement involving a t(2;3)(p11;q27) translocation that affects the ABR in an unusual combination with the IGK locus.  相似文献   
95.
Ultrasound (US) imaging is a well-established diagnostic technique to image soft tissues in real time, while photoacoustic (PA) is an emerging imaging technique employed to collect molecular information. Integration of PA and US imaging provides complementary information enhancing diagnostic accuracy without employing ionizing radiations. The development of contrast agents able to combine PA and US features is pivotal to improve the significance of PAUS imaging and for PAUS-guided treatment of neoplasms. Here, we demonstrate in relevant ex-vivo models that disassembling passion fruit-like nano-architectures (pfNAs) can be employed in PAUS imaging. pfNAs are composed by silica nanocapsules comprising aggregates of commercial NIR-dyes-modified polymers and ultrasmall gold nanoparticles. The intrinsic US and PA features of pfNAs have been fully characterized and validated in tissue-mimicking materials and in ex vivo preparations. Moreover, the application of a multi-parametric approach has allowed the increase of information extrapolated from collected images for a fine texture analysis.  相似文献   
96.
Background

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) leads to prolonged survival for selected patients with colorectal (CRC) peritoneal metastases (PM). This study aimed to analyze the prognostic role of micro-satellite (MS) status and RAS/RAF mutations for patients treated with CRS.

Methods

Data were collected from 13 Italian centers with PM expertise within a collaborative group of the Italian Society of Surgical Oncology. Clinical and pathologic variables and KRAS/NRAS/BRAF mutational and MS status were correlated with overall survival (OS) and disease-free survival (DFS).

Results

The study enrolled 437 patients treated with CRS-HIPEC. The median OS was 42.3 months [95% confidence interval (CI), 33.4–51.2 months], and the median DFS was 13.6 months (95% CI, 12.3–14.9 months). The local (peritoneal) DFS was 20.5 months (95% CI, 16.4–24.6 months). In addition to the known clinical factors, KRAS mutations (p = 0.005), BRAF mutations (p = 0.01), and MS status (p = 0.04) were related to survival. The KRAS- and BRAF-mutated patients had a shorter survival than the wild-type (WT) patients (5-year OS, 29.4% and 26.8% vs 51.5%, respectively). The patients with micro-satellite instability (MSI) had a longer survival than the patients with micro-satellite stability (MSS) (5-year OS, 58.3% vs 36.7%). The MSI/WT patients had the best prognosis. The MSS/WT and MSI/mutated patients had similar survivals, whereas the MSS/mutated patients showed the worst prognosis (5-year OS, 70.6%, 48.1%, 23.4%; p = 0.0001). In the multivariable analysis, OS was related to the Peritoneal Cancer Index [hazard ratio (HR), 1.05 per point], completeness of cytoreduction (CC) score (HR, 2.8), N status (HR, 1.6), signet-ring (HR, 2.4), MSI/WT (HR, 0.5), and MSS/WT-MSI/mutation (HR, 0.4). Similar results were obtained for DFS.

Conclusion

For patients affected by CRC-PM who are eligible for CRS, clinical and pathologic criteria need to be integrated with molecular features (KRAS/BRAF mutation). Micro-satellite status should be strongly considered because MSI confers a survival advantage over MSS, even for mutated patients.

  相似文献   
97.
Spinel phases, with unique and outstanding physical properties, are attracting a great deal of interest in many fields. In particular, MgFe2O4, a partially inverted spinel phase, could find applications in medicine thanks to the remarkable antibacterial properties attributed to the generation of reactive oxygen species. In this paper, undoped and Ag-doped MgFe2-xAgxO4 (x = 0.1 and 0.3) nanoparticles were prepared using microwave-assisted combustion and sol–gel methods. X-ray powder diffraction, with Rietveld structural refinements combined with micro-Raman spectroscopy, allowed to determine sample purity and the inversion degree of the spinel, passing from about 0.4 to 0.7 when Ag was introduced as dopant. The results are discussed in view of the antibacterial activity towards Escherichia coli and Staphylococcus aureus, representative strains of Gram-negative and Gram-positive bacteria. The sol–gel particles were more efficient towards the chosen bacteria, possibly thanks to the nanometric sizes of metallic silver, which were well distributed in the powders and in the spinel phase, with respect to microwave ones, that, however, acquired antibacterial activity after thermal treatment, probably due to the nucleation of hematite, itself displaying well-known antibacterial properties and which could synergistically act with silver and spinel.  相似文献   
98.
Journal of Interventional Cardiac Electrophysiology - The purpose of the study was to evaluate the impact of left atrial posterior wall isolation (LAPWI) in addition to pulmonary vein isolation...  相似文献   
99.
100.
Melatonin protects neurons from singlet oxygen-induced apoptosis   总被引:2,自引:2,他引:2  
Abstract: Singlet oxygen (O2[1Δg]) is a very reactive molecule that can be produced by living cells and may contribute to cytotoxicity. The pineal hormone melatonin has been reported to possess potent antioxidant activity, and to be capable of scavenging O2(1Δg). We investigated whether melatonin might reduce the neurotoxic action of O2(lΔg). The cytotoxic effect of singlet oxygen was studied in primary cultures of cerebellar granule neurons pretreated with a photosensitive dye, rose bengal, and exposed to light—a procedure that generates O2(1Δg). We found that this procedure triggers neuronal death, which is preceded by mitochondrial impairment (assayed by the rate of the reduction of MTT, 3-[4,5-di-methylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide, into formazan), and by DNA fragmentation—a marker of apoptosis. DNA fragmentation was determined in situ by terminal deoxynucleotidyl transferase assay; cell death was assayed with 0.4% trypan blue solution—viable cells with an intact membrane are not permeable to trypan blue; dead cells are, and thus, they are stained blue. Neuroprotection was obtained with the pineal hormone melatonin. In a cell-free system, melatonin also protected the enzyme creatine kinase (EC 2.7.3.2) from the rose bengal-induced injury. The results suggest that melatonin might counteract the cytotoxic action of singlet oxygen. Further studies are needed to clarify the exact role singlet oxygen and melatonin might play in neurodegenerative diseases.  相似文献   
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