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961.
962.
Alfredo Ferro Rosalba Giugno Giuseppe Pigola Alfredo Pulvirenti Cinzia Di Pietro Michele Purrello Marco Ragusa 《BMC bioinformatics》2007,8(1):58
Background
Backtranslation is the process of decoding a sequence of amino acids into the corresponding codons. All synthetic gene design systems include a backtranslation module. The degeneracy of the genetic code makes backtranslation potentially ambiguous since most amino acids are encoded by multiple codons. The common approach to overcome this difficulty is based on imitation of codon usage within the target species. 相似文献963.
964.
Alessandra Battaglia Alexia Buzzonetti Cinzia Baranello Gabriella Ferrandina Enrica Martinelli Francesco Fanfani Giovanni Scambia Andrea Fattorossi 《Cancer immunology, immunotherapy : CII》2009,58(9):1363-1373
Objective We compared the immune system state in metastatic tumour draining lymph nodes (mTDLN) and metastasis free TDLN (mfTDLN) in
53 early stage cervical cancer patients to assess whether the presence of metastatic tumour cells worsen the balance between
an efficacious anti-tumour and a tolerogenic microenvironment.
Methods The immune system state was measured by immunophenotypic and functional assessment of suppressor and effector immune cell
subsets.
Results Compared to mfTDLN, mTDLN were significantly enriched in CD4+Foxp3+ regulatory T cells (Treg), which, in addition, exhibited an activated phenotype (HLA-DR+ and CD69+). Treg in mTDLN were also significantly enriched in neuropilin-1 (Nrp1) expressing cells, a subset particularly potent in
dampening T cell responses. mTDLN tended to be enriched in a population of CD8+Foxp3+T cells (operationally defined as CD8+Treg) that showed a suppressor potency similar to Treg under the same experimental conditions. Plasmacytoid dendritic cells
(pDC) and myeloid DC (mDC) generally show distinct roles in inducing T cell tolerance and activation, respectively. In line
with the excess of suppressor T cells, the ratio pDC to mDC was significantly increased in mTDLN. Immunohistochemical testing
showed that metastatic tumour cells produced the vascular endothelial growth factor, a natural ligand for Nrp1 expressed on
the cell surface of Nrp1+Treg and pDC, and therefore a potential mediator by which tumour cells foster immune privilege in mTDLN. Consistent with the
overall tolerogenic profile, mTDLN showed a significant Tc2 polarisation and tended to contain lower numbers of CD45RA+CD27− effector memory CD8+T cells.
Conclusions The increased recruitment of suppressor type cells concomitant with the scarcity of cytotoxic type cells suggests that in
mTDLN the presence of tumour cells could tip the balance against anti-tumour immune response facilitating the survival of
metastatic tumour cells and possibly contributing to systemic tolerance. 相似文献
965.
Susanna Amadio Fabrizio Vacca Alessandro Martorana Giuseppe Sancesario Cinzia Volonté 《BMC developmental biology》2007,7(1):77
Background
In the CNS, several P2 receptors for extracellular nucleotides are identified on neurons and glial cells to participate to neuron-neuron, glia-glia and glia-neuron communication. 相似文献966.
Adriano Guido Antonella Cinzia Marra Adelaide Mastandrea Fabio Tosti Franco Russo 《Facies》2012,58(2):179-190
The site of Cessaniti (Vibo Valentia, Italy) has been well known since the 19th century for the richness and good preservation
of its Miocene fauna and flora. The sedimentary succession of the site represents a paralic system that evolved toward an
open-marine environment recording the Tortonian transgression. The fossil assemblage contains rich invertebrate (corals, bivalves,
gastropods, brachiopods, echinoids, benthic and planktonic foraminifers) and vertebrate faunas (proboscideans, rhinoceroses,
giraffids, bovids, sirenids, marine turtles, and fish remains). The fossils recovered at the Cessaniti site have a relevant
role in phylogenetic studies and paleogeographic reconstructions of Late Miocene environments of the southern Italy. This
research is focused on the microstructure and preservation state of the fossil bones. Samples of Metaxytherium sp. bones have been analyzed to understand the diagenetic profile of the bone assemblages that characterizes the taphonomic history
of the Cessaniti site. The analyses provided a comprehensive account of how bone mineral (bioapatite) has been altered and
demonstrated that the post-burial processes did not significantly affect the micromorphological and biogeochemical features
of the bones. The excellent preservation state of the bones strengthens the importance of the Cessaniti site for studies of
the Mediterranean Miocene vertebrate fauna. 相似文献
967.
Deletion of DNA lying close to the glkA locus induces ectopic sporulation in Streptomyces coelicolor A3(2) 总被引:1,自引:1,他引:0
Gabriella H. Kelemen Kitty A. Plaskitt Cinzia G. Lewis Kim C. Findlay Mark J. Buttner 《Molecular microbiology》1995,17(2):221-230
Streptomyces coelicolor A3(2) J1668 sporulated ectopically in the substrate hyphae (the Esp phenotype) with the same time course as sporulation in the aerial hyphae. Examination of related strains implied that the Esp phenotype was caused by the deletion of DNA that lies close to, but is distinct from, the glucose kinase gene ( glkA ). Co-transduction of the Esp phenotype with the deletion present in J1668 confirmed this hypothesis. The size of the deletion was found to be 7.4 kb. Construction of a strain carrying both the J1668 deletion and a whiG mutation demonstrated that the Esp phenotype depends on at least one of the genes required for the differentiation of aerial hyphae into spores. 相似文献
968.
Diversity, Dynamics, and Activity of Bacterial Communities during Production of an Artisanal Sicilian Cheese as Evaluated by 16S rRNA Analysis 总被引:15,自引:1,他引:14 下载免费PDF全文
969.
970.
Semiparametric regression for count data 总被引:3,自引:0,他引:3