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991.

Objectives:  

To examine how adolescent physical activity (PA) and screen-based media sedentary behaviours (SBM) relate to psychological and social health and identify cross-national differences in these relationships.  相似文献   
992.
Motor neuron degeneration is the predominant pathological feature of spinal muscular atrophy (SMA). In patients with severe forms of the disease, additional sensory abnormalities have been reported. However, it is not clear whether the loss of sensory neurons is a common feature in severe forms of the disease, how many neurons are lost and how loss of sensory neurons compares with motor neuron degeneration. We have analysed dorsal root ganglionic sensory neurons in Smn-/-;SMN2 mice, a model of type I SMA. In contrast to lumbar motor neurons, no loss of sensory neurons in the L5 dorsal root ganglia is found at post-natal days 3-5 when these mice are severely paralyzed and die from motor defects. Survival of cultured sensory neurons in the presence of NGF and other neurotrophic factors is not reduced in comparison to wild-type controls. However, isolated sensory neurons have shorter neurites and smaller growth cones, and beta-actin protein and beta-actin mRNA are reduced in sensory neurite terminals. In footpads of Smn-deficient mouse embryos, sensory nerve terminals are smaller, suggesting that Smn deficiency reduces neurite outgrowth during embryogenesis. These data indicate that pathological alterations in severe forms of SMA are not restricted to motor neurons, but the defects in the sensory neurons are milder than those in the motor neurons.  相似文献   
993.
Natural IgE production in the absence of MHC Class II cognate help   总被引:1,自引:0,他引:1  
IgE induction by parasites and allergens is antigen driven and cognate T cell help dependent. We demonstrate that spontaneously produced IgE in T cell-deficient and germ-free wild-type (wt) mice is composed of natural specificities and induced by a mechanism independent of MHC class II (MHC II) cognate help. This does not require secondary lymphoid structures or germinal center formation, although some bystander T cell-derived IL-4 is necessary. The pathway of spontaneous IgE production is not inhibited by regulatory T cells and increases with age to constitute significant serum concentrations, even in naive animals.  相似文献   
994.
995.
To optimize the development of stem cell (SC)-based therapies for the treatment of glioblastoma (GBM), we compared the pathotropism of 2 SC sources, human mesenchymal stem cells (hMSCs) and fetal neural stem cells (fNSCs), toward 2 orthotopic GBM models, circumscribed U87vIII and highly infiltrative GBM26. High resolution and contrast-enhanced (CE) magnetic resonance imaging (MRI) were performed at 14.1 Tesla to longitudinally monitor the in vivo location of hMSCs and fNSCs labeled with the same amount of micron-size particles of iron oxide (MPIO). To assess pathotropism, SCs were injected in the contralateral hemisphere of U87vIII tumor-bearing mice. Both MPIO-labeled SC types exhibited tropism to tumors, first localizing at the tumor edges, then in the tumor masses. MPIO-labeled hMSCs and fNSCs were also injected intratumorally in mice with U87vIII or GBM26 tumors to assess their biodistribution. Both SC types distributed throughout the tumor in both GBM models. Of interest, in the U87vIII model, areas of hyposignal colocalized first with the enhancing regions (ie, regions of high vascular permeability), consistent with SC tropism to vascular endothelial growth factor. In the GBM26 model, no rim of hyposignal was observed, consistent with the infiltrative nature of this tumor. Quantitative analysis of the index of dispersion confirmed that both MPIO-labeled SC types longitudinally distribute inside the tumor masses after intratumoral injection. Histological studies confirmed the MRI results. In summary, our results indicate that hMSCs and fNSCs exhibit similar properties regarding tumor tropism and intratumoral dissemination, highlighting the potential of these 2 SC sources as adequate candidates for SC-based therapies.  相似文献   
996.
997.

Background

To evaluate tolerability and maintenance of dose intensity of 2 weekly treatment with vincristine, doxorubicin, cyclophosphamide alternating with ifosfamide, etoposide (VDC/IE) in patients with advanced small round cell sarcomas including Ewing family tumours (EFT), desmoplastic small round cell tumours (DSRCT) and undifferentiated high grade round cell sarcomas (UHGRCS).

Methods

Retrospective review of 16 patients treated at a single centre with VDC/IE. Dose received, treatment delay, toxicity and clinical outcome were recorded for each cycle up to a maximum of 14 cycles.

Results

A total 193 cycles of VDC/IE were administered to 10 patients with EFT, 4 with DSRCT and 2 with UHGRCS. Median age was 22 years with 75% over 18 years. Metastases were present in 14 patients. The mean duration of each cycle was 16.7 days. Febrile neutropenia occurred in 14 % of cycles, and grade 3/4 haematologic toxicity including anaemia and thrombocytopenia in 16 % and 11 % of cycles respectively. Seven patients had a dose reduction. Five patients discontinued VDC/IE early due to toxicity.

Conclusions

This schedule of VDC/IE is feasible in patients with EFT and DSRCT including adults and those with metastases. Its comparison with other standard regimens for these diseases is justified.
  相似文献   
998.
A loss of neurons is observed in the hippocampus of many patients with epilepsies of temporal lobe origin. It has been hypothesized that damage limitation or repair, for example using neurotrophic factors (NTFs), may prevent the transformation of a normal tissue into epileptic (epileptogenesis). Here, we used viral vectors to locally supplement two NTFs, fibroblast growth factor–2 (FGF-2) and brain-derived neurotrophic factor (BDNF), when epileptogenic damage was already in place. These vectors were first characterized in vitro, where they increased proliferation of neural progenitors and favored their differentiation into neurons, and they were then tested in a model of status epilepticus-induced neurodegeneration and epileptogenesis. When injected in a lesioned hippocampus, FGF-2/BDNF expressing vectors increased neuronogenesis, embanked neuronal damage, and reduced epileptogenesis. It is concluded that reduction of damage reduces epileptogenesis and that supplementing specific NTFs in lesion areas represents a new approach to the therapy of neuronal damage and of its consequences.  相似文献   
999.
ObjectivesTo review the treatment, toxicity, and outcomes in patients with Stage II seminoma after orchidectomy.Materials and methodsA retrospective chart review of all patients with Stage II seminoma referred for initial treatment, from 1965 to 2005, was performed. Treatment approaches, toxicity, and outcomes were analyzed.ResultsA total of 106 patients (83 with Stage IIA, 19 with Stage IIB, and 4 with Stage IIC) were seen between 1965 and 2005. Median age at diagnosis was 36 years (range: 19–71). Median follow-up was 21 years (range: 1.2–42). Eighty-nine patients were treated with adjuvant radiotherapy alone; 13 patients received a combined treatment modality with chemotherapy and radiotherapy after orchidectomy, 4 patients were treated with chemotherapy alone. Generally the treatment was well tolerated, with the main toxicity occurring in patients treated with extended-field radiotherapy. The 5-year disease-specific survival was 96% for the entire group. The 5-year relapse-free survivals for Stages IIA, IIB, and IIC disease were 94%, 72.5%, and 75%, respectively. Fifteen patients developed a relapse and were managed by chemotherapy; 5 of them achieved complete remission and remain free from further recurrence at last follow-up, while 10 died of the disease. Second malignancies were diagnosed in 4 (3.7%) patients during the follow-up.ConclusionsIn Stage IIA seminoma, radiotherapy continues to provide excellent results, as the majority of patients will be cured with this treatment alone. Radiotherapy or chemotherapy should be offered as an alternative to Stage IIB patients. Chemotherapy remains the treatment of choice for Stage IIC seminoma.  相似文献   
1000.
Metallo-β-lactamases (MBLs) can confer resistance to most β-lactams, including carbapenems. Their emergence in gram-negative pathogens is a matter of major concern. Italy was the first European country to report the presence of acquired MBLs in gram-negative pathogens and is one of the countries where MBL producers have been detected repeatedly. Here, we present the results of the first Italian nationwide survey of acquired MBLs in gram-negative pathogens. Of 14,812 consecutive nonreplicate clinical isolates (12,245 Enterobacteriaceae isolates and 2,567 gram-negative nonfermenters) screened for reduced carbapenem susceptibility during a 4-month period (September to December 2004), 30 isolates (28 Pseudomonas aeruginosa isolates, 1 Pseudomonas putida isolate, and 1 Enterobacter cloacae isolate) carried acquired MBL determinants. MBL producers were detected in 10 of 12 cities, with a predominance of VIM-type enzymes over IMP-type enzymes (4:1). Although having an overall low prevalence (1.3%) and significant geographical differences, MBL-producing P. aeruginosa strains appeared to be widespread in Italy, with a notable diversity of clones, enzymes, and integrons carrying MBL gene cassettes.  相似文献   
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