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101.
Sala E Villa N Crosti F Miozzo M Perego P Cappellini A Bonazzi C Barisani D Dalprà L 《Cancer Genetics and Cytogenetics》2007,173(2):164-169
We describe the case of a young woman showing yolk sac tumors (YST) and a Sertoli-Leydig cell tumor (SLCT) in the right ovary, with recurrences in the right adnexum and with hepatic metastasis. To our knowledge, YST and SLCT have never been described as components of the same tumor or reported as associated in the same patient. The patient's karyotype showed the presence of Y chromosome inserted into the 1qh region; the inserted region corresponded to Yq12 heterochromatin. LOH analysis revealed 1p36 paternal allele loss in the proband tumor, thus supporting a germ cell origin for the tumor. The presence of Y heterochromatin in 1qh DNA might induce disturbances in the normal regulation of oncogenes located in 1q. 相似文献
102.
Chen JF Sonsalla PK Pedata F Melani A Domenici MR Popoli P Geiger J Lopes LV de Mendonça A 《Progress in neurobiology》2007,83(5):310-331
This review summarizes recent developments that have contributed to understand how adenosine receptors, particularly A2A receptors, modulate brain injury in various animal models of neurological disorders, including Parkinson's disease (PD), stroke, Huntington's disease (HD), multiple sclerosis, Alzheimer's disease (AD) and HIV-associated dementia. It is clear that extracellular adenosine acting at adenosine receptors influences the functional outcome in a broad spectrum of brain injuries, indicating that A2A Rs may modulate some general cellular processes to affect neuronal cells death. Pharmacological, neurochemical and molecular/genetic approaches to the complex actions of A2A receptors in different cellular elements suggest that A2A receptor activation can be detrimental or protective after brain insults, depending on the nature of brain injury and associated pathological conditions. An interesting concept that emerges from these studies is A2A R's ability to fine tune neuronal and glial functions to produce neuroprotective effects. While the data presented here clearly highlight the complexity of using adenosinergic agents therapeutically in PD and other neurodegenerative disorders and point out many areas for further inquiry, they also confirm that adenosine receptor ligands, particularly A2A receptor ligands, have many promising characteristics that encourage the pursuit of their therapeutic potential. 相似文献
103.
Popoli P Blum D Martire A Ledent C Ceruti S Abbracchio MP 《Progress in neurobiology》2007,81(5-6):331-348
The aim of this review is to summarize and critically discuss the complex role played by adenosine A2A receptors (A2ARs) in Huntington's disease (HD). Since A2ARs are mainly localized on the neurons, which degenerate early in HD, and given their ability to stimulate glutamate outflow and inflammatory gliosis, it was hypothesized that they could be involved in the pathogenesis of HD, and that A2AR antagonists could be neuroprotective. This was further sustained by the demonstration that A2ARs and underlying signaling systems undergo profound changes in cellular and animal models of HD. More recently, however, the equation A2A receptor blockade = neuroprotection has appeared too simplistic. First, it is now definitely clear that, besides mediating ‘bad’ responses (for example, stimulation of glutamate outflow and excessive glial activation), A2ARs also promote ‘good’ responses (such as trophic and antinflammatory effects). This implies that A2AR blockade results either in pro-toxic or neuroprotective effects according to the mechanisms involved in a given experimental model. Second, since HD is a chronically progressive disease, the multiple mechanisms involving A2ARs may play different relative roles along the degenerative process. Such different mechanisms can be influenced by A2AR activation or blockade in different ways, even leading to opposite outcomes depending on the time of agonist/antagonist administration. The number, and the complexity, of the possible scenarios is further increased by the influence of mutant Huntingtin on both the expression and functions of A2ARs, and by the strikingly different effects mediated by A2ARs expressed by different cell populations within the brain. 相似文献
104.
Borrelia lusitaniae in immature Ixodes ricinus (Acari: Ixodidae) feeding on common wall lizards in Tuscany, central Italy 总被引:1,自引:0,他引:1
Amore G Tomassone L Grego E Ragagli C Bertolotti L Nebbia P Rosati S Mannelli A 《Journal of medical entomology》2007,44(2):303-307
Lizards and small rodents were live captured in Tuscany, central Italy, from May through August 2005. Prevalence of infestation by larval Ixodes ricinus L. (Acari: Ixodidae) and mean numbers of larvae per host were not significantly different for common wall lizards, Podarcis muralis Laurenti, and Apodemus spp. mice, whereas infestation levels by nymphs were significantly greater on lizards. Borrelia lusitaniae, which was previously shown to be dominant in host-seeking I. ricinus in the same study area, was detected by polymerase chain reaction (PCR) in 19.8% (95% confidence interval: 14.4, 26.0) of larval ticks and in 52.9% (27.8, 77.0) of nymphs that were collected from lizards. Moreover, 18.8% (7.2, 36.4) and 25.0 (3.2, 65.1) of lizards' tail biopsies and blood samples, respectively, were positive for B. lusitaniae. Conversely, attached ticks and ear biopsies from Apodemus spp. mice were PCR negative. Passerine birds belonging to 10 species were live captured in March 2005, and Borrelia valaisiana was detected in 57.1% (18.4, 90.1) of I. ricinus nymphs feeding on Eurasian blackbirds, Turdus merula L. Results of this study suggest that lizards play an important role as reservoirs for B. lusitanae and may affect the dominance of this genospecies in the Mediterranean area. 相似文献
105.
Laura?VerganiEmail author Giulia?Vecchione Francesca?Baldini Elena?Grasselli Adriana?Voci Piero?Portincasa Pier?Francesco?Ferrari Bahar?Aliakbarian Alessandro?A.?Casazza Patrizia?Perego 《European journal of nutrition》2018,57(5):1793-1805
Purpose
Phenolic compounds (PC) of virgin olive oil exert several biochemical and pharmacological beneficial effects. Some dietary PC seem to prevent/improve obesity and metabolic-related disorders such as non-alcoholic fatty liver disease (NAFLD). We investigated the possible effects of PC extracted from olive pomace (PEOP) and of the main single molecules present in the extract (tyrosol, apigenin, oleuropein, p-coumaric and caffeic acid) in protecting hepatocytes and endothelial cells against triglyceride accumulation and oxidative stress.Methods
Rat hepatoma and human endothelial cells were exposed to a mixture of oleate/palmitate to mimic the condition of NAFLD and atherosclerosis, respectively. Then, cells were incubated for 24 h in the absence or in the presence of PC or PEOP. Different parameters were evaluated, such as lipid accumulation and oxidative stress-related markers.Results
In hepatic cells, expression of peroxisome proliferator-activated receptors (PPARs) and of stearoyl-CoA desaturase 1 (SCD-1) were assessed as index of lipid metabolism. In endothelial cells, expression of intercellular adhesion molecule-1 (ICAM-1), activation of nuclear factor kappa-B (NF-kB), release of nitric oxide (NO), and wound-healing rate were assessed as index of inflammation.Conclusion
PEOP extract ameliorated hepatic lipid accumulation and lipid-dependent oxidative imbalance thus showing potential applications as therapeutic agent tuning down hepatosteatosis and atherosclerosis.106.
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