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21.
Fabio Moda Chiara Vimercati Ilaria Campagnani Margherita Ruggerone Giorgio Giaccone Michela Morbin Lorena Zentilin Mauro Giacca Ileana Zucca Giuseppe Legname Fabrizio Tagliavini 《朊病毒》2012,6(4):383-390
Prion diseases are caused by a conformational modification of the cellular prion protein (PrPC) into disease-specific forms, termed PrPSc, that have the ability to interact with PrPC promoting its conversion to PrPSc. In vitro studies demonstrated that anti-PrP antibodies inhibit this process. In particular, the single chain variable fragment D18 antibody (scFvD18) showed high efficiency in curing chronically prion-infected cells. This molecule binds the PrPC region involved in the interaction with PrPSc thus halting further prion formation. These findings prompted us to test the efficiency of scFvD18 in vivo. A recombinant Adeno-Associated Viral vector serotype 9 was used to deliver scFvD18 to the brain of mice that were subsequently infected by intraperitoneal route with the mouse-adapted scrapie strain RML. We found that the treatment was safe, prolonged the incubation time of scrapie-infected animals and decreased the burden of total proteinase-resistant PrPSc in the brain, suggesting that scFvD18 interferes with prion replication in vivo. This approach is relevant for designing new therapeutic strategies for prion diseases and other disorders characterized by protein misfolding. 相似文献
22.
Pyriforms are ovarian follicle nurse cells that undergo apoptosis at the end of previtellogenesis and are completely eliminated
by the epithelium. This event is accompanied by the active transfer of organelles and macromolecules to the oocyte via an
intercellular bridge. Since it would be a nonsense for damaged mitochondria to reach the oocyte, we have postulated that pyriform
cells have adapted their apoptotic machinery to prevent mitochondrial degradation. To verify this hypothesis, we have studied
mitochondrial morphology and functionality during follicle cell regression. Cytological and biochemical evidence indicates
that mitochondria in pyriforms maintain their size, organization and membrane potential. This clearly indicates that they
are not involved in apoptosis signalling/progression. This block would favour both the oocyte, by increasing the pool of organelles
available from follicle cells, and also the regressing pyriforms, by maintaining the energy resources required for completion
of their nurse function. The block is probably attributable to an over-expression of Bcl-2 and might be carried out by sequestering
cytochrome c inside the organelles. As demonstrated by in vitro experiments, the mitochondrial apoptosis pathway can be activated
by stress induction, such as serum deprivation, but not following physiological pro-apoptotic signalling, such as treatment
with gonadotrophin-releasing hormone.
These studies were supported by a grant from the MIUR (PRIN project: Molecular responses of embryonic, differentiated and
tumoral cells exposed to cadmium intoxication). 相似文献
23.
24.
Ekaterini Blaveri Fiona Kelly Alessandra Mallei Kriss Harris Adam Taylor Juliet Reid Maria Razzoli Lucia Carboni Chiara Piubelli Laura Musazzi Girogio Racagni Aleksander Mathé Maurizio Popoli Enrico Domenici Stewart Bates 《PloS one》2010,5(9)
Background
The Flinders model is a validated genetic rat model of depression that exhibits a number of behavioural, neurochemical and pharmacological features consistent with those observed in human depression.Principal Findings
In this study we have used genome-wide microarray expression profiling of the hippocampus and prefrontal/frontal cortex of Flinders Depression Sensitive (FSL) and control Flinders Depression Resistant (FRL) lines to understand molecular basis for the differences between the two lines. We profiled two independent cohorts of Flinders animals derived from the same colony six months apart, each cohort statistically powered to allow independent as well as combined analysis. Using this approach, we were able to validate using real-time-PCR a core set of gene expression differences that showed statistical significance in each of the temporally distinct cohorts, representing consistently maintained features of the model. Small but statistically significant increases were confirmed for cholinergic (chrm2, chrna7) and serotonergic receptors (Htr1a, Htr2a) in FSL rats consistent with known neurochemical changes in the model. Much larger gene changes were validated in a number of novel genes as exemplified by TMEM176A, which showed 35-fold enrichment in the cortex and 30-fold enrichment in hippocampus of FRL animals relative to FSL.Conclusions
These data provide significant insights into the molecular differences underlying the Flinders model, and have potential relevance to broader depression research. 相似文献25.
Céline Di Battista Antonella Amicucci Chiara Guidi Luana Bertini Davide Sisti Vilberto Stocchi 《Biotechnology Techniques》1999,13(5):331-335
A rapid procedure has been developed to isolate DNA from the ectomycorrhizae of Tuber spp. for use in PCR experiments. The method described is fast and sensitive and can overcome the amplification problems that can arise in the presence of inhibitors. For this reason it can be used to type ectomycorrhizae even starting from a single root tip and make mycorrhizae identification much more rapid. 相似文献
26.
Tivodar S Paladino S Pillich R Prinetti A Chigorno V van Meer G Sonnino S Zurzolo C 《FEBS letters》2006,580(24):5705-5712
Detergent-resistant membranes (DRMs) represent specialized membrane domains resistant to detergent extraction, which may serve to segregate proteins in a specific environment in order to improve their function. Segregation of glycosylphosphatidylinositol-anchored proteins (GPI-APs) in DRMs has been shown to be involved in their sorting to the apical membrane in polarized epithelial cells. Nonetheless, we have shown that both apical and basolateral GPI-APs associate with DRMs. In this report we investigated the lipid composition of DRMs associated with an apical and a basolateral GPI-AP. We found that apical and basolateral DRMs contain the same lipid species although in different ratios. This specific lipid ratio is maintained after mixing the cells before lysis indicating that DRMs maintain their identity after Triton extraction. 相似文献
27.
Artem Pankin Chiara Campoli Xue Dong Benjamin Kilian Rajiv Sharma Axel Himmelbach Reena Saini Seth J Davis Nils Stein Korbinian Schneeberger Maria von Korff 《Genetics》2014,198(1):383-396
Phytochromes play an important role in light signaling and photoperiodic control of flowering time in plants. Here we propose that the red/far-red light photoreceptor HvPHYTOCHROME C (HvPHYC), carrying a mutation in a conserved region of the GAF domain, is a candidate underlying the early maturity 5 locus in barley (Hordeum vulgare L.). We fine mapped the gene using a mapping-by-sequencing approach applied on the whole-exome capture data from bulked early flowering segregants derived from a backcross of the Bowman(eam5) introgression line. We demonstrate that eam5 disrupts circadian expression of clock genes. Moreover, it interacts with the major photoperiod response gene Ppd-H1 to accelerate flowering under noninductive short days. Our results suggest that HvPHYC participates in transmission of light signals to the circadian clock and thus modulates light-dependent processes such as photoperiodic regulation of flowering. 相似文献
28.
Michele Carbonelli Chiara La Morgia Giacomo Savini Maria Lucia Cascavilla Enrico Borrelli Filipe Chicani Carolina do V. F. Ramos Solange R. Salomao Vincenzo Parisi Jerry Sebag Francesco Bandello Alfredo A. Sadun Valerio Carelli Piero Barboni 《PloS one》2015,10(6)
Purpose
To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).Methods
All patients with molecularly confirmed MON, i.e. Leber’s Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.Results
MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.Conclusion
The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces. 相似文献29.
HOTAIR role in melanoma progression and its identification in the blood of patients with advanced disease 下载免费PDF全文
30.
Loredana R Barbara D Annamaria L Stefania T Maria MC Silvana F Piero A Marina P 《Molecular reproduction and development》2003,66(1):54-59
In the present paper we investigated the role played by apoptosis during oogenesis in the cartilaginous fish Torpedo marmorata. TEM, TUNEL and immunohistochemical techniques were employed to specifically reveal morphological and biochemical hallmarks of apoptosis in specimens from birth to sexual maturity. Data obtained demonstrate that apoptosis occurs in prefollicular oocyte selection, in maintaining the homeostasis of granulosa in healthy growing oocyte and in resorbing atretic follicles. In this respect, the involvement of apoptosis in Torpedo marmorata oogenesis closely parallels that found in mammals, thus confirming that strategies of germ cell selection among vertebrates have been evolutionarily preserved. 相似文献