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191.
George Calin Guglielmina N Ranzani Dino Amadori Vlad Herlea Irina Matei Giuseppe Barbanti-Brodano Massimo Negrini 《BMC genetics》2001,2(1):14-7
Background
Genomic instability has been reported at microsatellite tracts in few coding sequences. We have shown that the Bloom syndrome BLM gene may be a target of microsatelliteinstability (MSI) in a short poly-adenine repeat located in its coding region. To further characterize the involvement of BLM in tumorigenesis, we have investigated mutations in nine genes containing coding microsatellites in microsatellite mutator phenotype (MMP) positive and negative gastric carcinomas (GCs). 相似文献192.
Santini E Feyder M Gangarossa G Bateup HS Greengard P Fisone G 《The Journal of biological chemistry》2012,287(33):27806-27812
Dyskinesia, a motor complication caused by prolonged administration of the antiparkinsonian drug l-3,4-dihydroxyphenylalanine (l-DOPA), is accompanied by activation of cAMP signaling and hyperphosphorylation of the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32). Here, we show that the abnormal phosphorylation of DARPP-32 occurs specifically in medium spiny neurons (MSNs) expressing dopamine D1 receptors (D1R). Using mice in which DARPP-32 is selectively deleted in D1R-expressing MSNs, we demonstrate that this protein is required for l-DOPA-induced activation of the extracellular signal-regulated protein kinases 1 and 2 and the mammalian target of rapamycin complex 1 (mTORC1) pathways, which are implicated in dyskinesia. We also show that mutation of the phosphorylation site for cAMP-dependent protein kinase on DARPP-32 attenuates l-DOPA-induced dyskinesia and reduces the concomitant activations of ERK and mTORC1 signaling. These studies demonstrate that, in D1R-expressing MSNs, l-DOPA-induced activation of ERK and mTORC1 requires DARPP-32 and indicates the importance of the cAMP/DARPP-32 signaling cascade in dyskinesia. 相似文献
193.
Sara Benedetti Pia Bernasconi Enrico Bertini Elena Biagini Giuseppe Boriani Cristina Capanni Nicola Carboni Giovanna Cenacchi Marta Columbaro Monica D’Adamo Adele D’Amico Maria Rosaria D’Apice Marianna Fontana Alessandra Gambineri Giovanna Lattanzi Rocco Liguori Nadir M Maraldi Laura Mazzanti Eugenio Mercuri Tiziana Mongini Lucia O Morandi Iria Neri Giovanni Nigro Giuseppe Novelli Michela Ortolani Renato Pasquali Antonella Pini Stefania Petrini Luisa Politano Stefano Previtali Lisa Pucci Claudio Rapezzi Giulia Ricci Carmelo Rodolico Paolo Sbraccia Emanuela Scarano Gabriele Siciliano Stefano Squarzoni Antonio Toscano Liliana Vercelli Matteo Ziacchi 《Orphanet journal of rare diseases》2012,7(1):1-3
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy. 相似文献
194.
Histone H4K20 tri‐methylation at late‐firing origins ensures timely heterochromatin replication 下载免费PDF全文
Charlotte Grimaud Paulina Prorok Christelle Cayrou Gunnar Schotta Alhassan F Abdelsamie Jérôme Déjardin Marcel Méchali Giuseppe Baldacci Claude Sardet Jean‐Charles Cadoret Aloys Schepers Eric Julien 《The EMBO journal》2017,36(18):2726-2741
Among other targets, the protein lysine methyltransferase PR‐Set7 induces histone H4 lysine 20 monomethylation (H4K20me1), which is the substrate for further methylation by the Suv4‐20h methyltransferase. Although these enzymes have been implicated in control of replication origins, the specific contribution of H4K20 methylation to DNA replication remains unclear. Here, we show that H4K20 mutation in mammalian cells, unlike in Drosophila, partially impairs S‐phase progression and protects from DNA re‐replication induced by stabilization of PR‐Set7. Using Epstein–Barr virus‐derived episomes, we further demonstrate that conversion of H4K20me1 to higher H4K20me2/3 states by Suv4‐20h is not sufficient to define an efficient origin per se, but rather serves as an enhancer for MCM2‐7 helicase loading and replication activation at defined origins. Consistent with this, we find that Suv4‐20h‐mediated H4K20 tri‐methylation (H4K20me3) is required to sustain the licensing and activity of a subset of ORCA/LRWD1‐associated origins, which ensure proper replication timing of late‐replicating heterochromatin domains. Altogether, these results reveal Suv4‐20h‐mediated H4K20 tri‐methylation as a critical determinant in the selection of active replication initiation sites in heterochromatin regions of mammalian genomes. 相似文献
195.
196.
Tarabbo M Lapa D Castilletti C Tommaselli P Guarducci R Lucà G Emanuele A Zaccaria O La Gioia VF Girardi E Capobianchi MR Ippolito G 《PloS one》2011,6(1):e15933
Background
Clinical surveillance may have underestimated the real extent of the spread of the new strain of influenza A/H1N1, which surfaced in April 2009 originating the first influenza pandemic of the 21st century. Here we report a serological investigation on an influenza A/H1N1pdm outbreak in an Italian military ship while cruising in the Mediterranean Sea (May 24-September 6, 2009).Methods
The contemporary presence of HAI and CF antibodies was used to retrospectively estimate the extent of influenza A/H1N1pdm spread across the crew members (median age: 29 years).Findings
During the cruise, 2 crew members fulfilled the surveillance case definition for influenza, but only one was laboratory confirmed by influenza A/H1N1pdm-specific RT-PCR; 52 reported acute respiratory illness (ARI) episodes, and 183 reported no ARI episodes. Overall, among the 211 crew member for whom a valid serological result was available, 39.3% tested seropositive for influenza A/H1N1pdm. The proportion of seropositives was significantly associated with more crowded living quarters and tended to be higher in those aged <40 and in those reporting ARI or suspected/confirmed influenza A/H1N1pdm compared to the asymptomatic individuals. No association was found with previous seasonal influenza vaccination.Conclusions
These findings underline the risk for rapid spread of novel strains of influenza A in confined environment, such as military ships, where crowding, rigorous working environment, physiologic stress occur. The high proportion of asymptomatic infections in this ship-borne outbreak supports the concept that serological surveillance in such semi-closed communities is essential to appreciate the real extent of influenza A/H1N1pdm spread and can constitute, since the early stage of a pandemic, an useful model to predict the public health impact of pandemic influenza and to establish proportionate and effective countermeasures. 相似文献197.
198.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
199.
The genetic differentiation among 33 populations of the Italian treefrog, Hyla intermedia (Anura: Hylidae), was investigated using both biparentally (23 allozyme loci) and maternally (partial mitochondrial cytochrome
b gene) inherited markers. Two main population groups were evidenced by both markers, located north and south of the northern
Apennines. However, the pattern of differentiation between these two groups was much less pronounced at allozymes than at
mtDNA, leading to gene flow estimates that were 25 times lower at mitochondrial than at nuclear level. Also, the mtDNA divergence
between the two groups was particularly marked for two cospecific lineages of anuran amphibians (the P-distance being on average 9.04%), while their average genetic distance at allozymes was comparatively low (D
NEI = 0.07). This contrasting pattern of nuclear versus mitochondrial genetic variation is discussed in the context of: (1) marker
specific selection, (2) secondary contact and sex-biased gene flow and (3) ancestral polymorphism and colonization from north
to south. Finally we emphasize how, for population genetic studies, the use of multiple markers having distinct evolutionary
properties can help unravel the existence of more complex evolutionary histories. 相似文献
200.
A general class of lumped parameter models describing the local dynamics of a tri-trophic chain in a controlled environment is analyzed in detail. The trophic functions characterizing the interactions are defined only by some properties and allow us to treat both prey-dependent and ratio-dependent models in a unified manner. Conditions for existence and stability of extinction and coexistence equilibrium states are determined. Some peculiar aspects of the dynamics of the system depending on the bioecological parameters are presented, with particular attention to bistability situations, limit cycles and chaotic behaviours. 相似文献