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Serotonin is a signal molecule with a wide range of functions in vertebrates. In Antarctic fishes, the serotonergic system has been studied in the brain, revealing differences from temperate fishes related to the long-term cold adaptation. To date, little is known regarding the peripheral nervous system, and no information is available for the stomach. In the present work, we contribute to fill the gaps by investigating the presence and the immunohistochemical distribution of serotonin in the stomach of the Antarctic silverfish Pleuragramma antarcticum, a cold-adapted key species of the Southern Ocean shelf food web. The main aim was to investigate the serotonergic system at the gastric level, in order to reveal possible peculiarities related to long-term cold adaptation, similar to the ones seen in the central nervous system of Antarctic fishes. Serotonin immunoreactivity was detected in the pyloric and cardiac mucosa of P. antarcticum stomach with immunopositive cells in the pyloric and cardiac surface epithelia and in the tubular glands. No immunopositive fibers and neuronal cell bodies were found. Our results highlight that the serotonin distribution pattern at the gastric level is similar to that described in temperate teleosts. This finding suggests that in P. antarcticum, long-term adaptations to the Antarctic condition do not affect the serotonergic system at the gastric level. In addition, our data constitute the baseline information for further investigations aimed at clarifying the effects of short-term temperature variations on the gastric serotonergic system of Antarctic species in the frame of the global climate change.  相似文献   
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Gliobastoma (GB), the most common adult brain tumor, infiltrates normal brain area rendering impossible the complete surgical resection, resulting in a poor median survival (14–15 months), despite the aggressive multimodality treatments post‐surgery, such as radiation and chemo‐therapy. GB is characterized by hypoxic and necrotic regions due to a poorly organized tumor vascularization, leading to inadequate blood supply and consequently to hypoxic and necrotic areas. We have previously shown that, under hypoxia GB primary cells increased the expression of stemness markers as well as the expression of the nuclear receptor peroxisome proliferator‐activated receptor α (PPARα) and also the crucial role played by PPARs in mouse neural stem cells maintenance and differentiation. Due to the importance of lipid signaling in cell proliferation and differentiation, in this work, we analyzed the expression of PPARs in GB neurospheres both in normoxic and hypoxic conditions. The results obtained suggest a differential regulation of the three PPARs by hypoxia, thus indicating a possible therapeutic strategy to counteract GB recurrencies. J. Cell. Biochem. 113: 3342–3352, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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The performance of the nitrate reductase assay (NRA) was compared with the proportion method (PM) on Lowenstein-Jensen medium and the BACTEC MGIT960 assay under routine conditions using 160 clinical isolates of Mycobacterium tuberculosis with a high proportion of resistant strains. The mean time to obtain results was 8.8 days and the overall agreements between NRA and PM and NRA and M960 were 95% and 94%, respectively. NRA was easy to perform and represents a useful tool for the rapid screening of drug-resistant M. tuberculosis strains in low-resource countries.  相似文献   
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The effects of tau hyperphosphorylation and aggregation on axonal transport were investigated in the optic nerve of mice transgenic for human mutant P301S tau. Transport was examined using cholera toxin B tracing. Retrograde transport was reduced in transgenic mice at 3 and 5 months of age, when compared to C57/Bl6 control mice. Anterograde axonal transport was also reduced in 3-month-old transgenic mice. Mild excitotoxic injury of retinal ganglion cells resulted in greater nerve cell loss in retinas from 3- and 5-month old P301S transgenic mice, when compared to controls. In conjunction with the detection of abnormal tau in the optic nerve in human and experimental glaucoma, the present findings suggest that tau hyperphosphorylation and aggregation may constitute targets for neuroprotective therapies in glaucoma as well as tauopathies.  相似文献   
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The aim of this study was to evaluate the efficacy of a food supplement combination based on isoflavones and berberine (ISB) in the treatment of menopausal symptoms and dyslipidaemia. Isoflavones are extracted from soy and absorbed in the body after being activated by lactobacillus. Berberine, extracted from the plant Berberis aristata, lowers plasma cholesterol and triglycerides (TG) by increasing low-density lipoprotein (LDL) receptors and reducing hepatic synthesis of TG. One hundred twenty women with a mean age of 54.8?±?0.6 years were enrolled and randomized to treatment with ISB (estromineral lipid [EL]?=?60 cases) or calcium and vitamin D(3) (CaD?=?60 cases). Menopausal symptoms, plasma cholesterol, and TG were evaluated at baseline, and after 4 and 12 weeks. EL treatment significantly lowered plasma total cholesterol (-13.5% ± 0.7 vs -0.2% ± 0.5), LDL cholesterol (-12.4% ± 1.5 vs + 0.8 % ± 0.7) and TG (-18.9% ± 2.5 vs -1.3% ± 1.2) and improved menopausal symptoms compared with CaD treatment. Safety parameters were unchanged during the study. The combination of berberine and isoflavones was effective in lowering cardiovascular (CV) risk factors in menopausal women with moderate dyslipidaemia and in improving their quality of life.  相似文献   
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The effect of a homologue series of nonionic surfactants, namely poly(ethylene glycol) (PEG) fatty acid esters, differing in oxyethylene (PEG 8, PEG 12, and PEG 40) and fatty acid (stearate, mono and di-laurate, and mono and di-oleate) chain lengths, on in vitro skin permeability of ketoprofen (KTP) vehicled in plasters was investigated. The drug diffusion through hairless mouse skin as well as the effect of the surfactant type and strength was studied by Franz diffusion cells and ATR-FTIR spectroscopy. The use of PEG stearate series revealed that the surfactant with the largest polar head, namely PEG 40, was ineffective in enhancing the skin permeation of KTP, independently of the plaster concentrations. The effect of the hydrophobic chain was investigated only by using the shortest oxyethylene chains. The experimental results revealed that the oxyethylene chain length of surfactants appeared to be more influent than the alkyl chain. The prediction of the absorption enhancing capability of these PEG derivatives appeared related to the vehicle other than the proper combination of the number of ethylene oxide groups and alkyl groups.  相似文献   
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