Search

Multiple Sclerosis (MS) displays a heterogeneous clinical onset and progression, which are mostly unpredictable, but demyelination of the central nervous system (CNS) leads to substantial deficits of sensory, motor, autonomic, and neurocognitive functions. Considering all genetic studies on MS, including the advanced genome-wide association studies, the risk linked to HLA alleles remains the highest among other susceptibility genetic variants. However, given the genetic variability of HLA alleles in different ethnic groups, we conducted a systematic review of reviews and meta-analyses aiming at summarizing all the results on the association between MS and HLA class II genes. We systematically searched meta-analyses and systematic reviews dealing with MS and HLA in all ethnicities. From 154 records, we included 5 articles collecting HLA data from 15,232 MS patients and 24,194 ethnically matched controls. DRB1∗15 (OR ranging from 1.39 in Chinese Han to 2.59 in Caucasians) and DQB1∗06:02 (OR ranging from 1.91 in Caucasians to 2.49 in Colombian) alleles confer an increased risk for MS transethnically (Caucasians, Chinese, South Americans, Carribeans, Middle Easterners, Japanese, and North Africans). DRB1∗01, DRB1∗09, DRB1∗11, DRB1∗12, and DRB1∗16 alleles were protective, in agreement with the type of amino-acidic (aa) residues (ranging from position 9 to 90) included in pockets 1, 4, 6, 7, and 9, which are most involved in peptide presentation. Changes in aa residues affect the capability of HLA molecules in binding myelin peptides. DQB1∗06:02 risk allele seems to be the most interesting target as humanized mice expressing only DQB1∗06:02 develop MS-like disease mediated by autoimmune reactions against myelin oligodendrocytic basic protein that stabilizes the myelin. Our summary of results from a high number of patients and controls suggests that allelic variants from both DQB1 and DRB1 genes are equally involved in MS susceptibility/protection transethnically.

Updating a knowledge base to remove an unwanted consequence is a challenging task. Some of the original sentences must be either deleted or weakened in such a way that the sentence to be removed is no longer entailed by the resulting set. On the other hand, it is desirable that the existing knowledge be preserved as much as possible, minimising the loss of information. Several approaches to this problem can be found in the literature. In particular, when the knowledge is represented by an ontology, two different families of frameworks have been developed in the literature in the past decades with numerous ideas in common but with little interaction between the communities: applications of AGM-like Belief Change and justification-based Ontology Repair. In this paper, we investigate the relationship between pseudo-contraction operations and gentle repairs. Both aim to avoid the complete deletion of sentences when replacing them with weaker versions is enough to prevent the entailment of the unwanted formula. We show the correspondence between concepts on both sides and investigate under which conditions they are equivalent. Furthermore, we propose a unified notation for the two approaches, which might contribute to the integration of the two areas.

International audience; Hundreds of fossil marine vertebrates cropping out at Cerro Colorado (Pisco Basin, Peru) are identified and reported on a 1:6500 scale geological map and in a joined stratigraphic section. All the fossils are from the lower strata of the Pisco Formation, dated in this area to the late middle or early late Miocene. They are particularly concentrated (88%) in the stratigraphic interval from 40 to 75 m above the unconformity with the underlying Chilcatay Formation. The impressive fossil assemblage includes more than 300 specimens preserved as bone elements belonging mostly to cetaceans (81%), represented by mysticetes (cetotheriids and balaenopteroids) and odontocetes (kentriodontid-like delphinidans, pontoporiids, ziphiids, and physeteroids, including the giant raptorial sperm whale Livyatan melvillei). Seals, crocodiles, sea turtles, seabirds, bony fish, and sharks are also reported. Isolated large teeth of Carcharocles and Cosmopolitodus are common throughout the investigated stratigraphical interval, whereas other shark teeth, mostly of carcharinids, are concentrated in one sandy interval. This work represents a first detailed census of the extraordinary paleontological heritage of the Pisco Basin and the basis for future taphonomic, paleoecological, and systematic studies, as well as a much needed conservation effort for this extremely rich paleontological site.

BACKGROUND: Mucinous colorectal cancer (CRC) exhibits distinct clinical and pathological features, including poorer response to fluorouracil (FU) compared with non-mucinous tumours.PATIENTS AND METHODS: We compared the expression of thymidylate synthase (TYMS) and topoisomerase-1 (TOPO1) and DNA microsatellite instability (MSI) in 87 patients (35 mucinous and 52 non-mucinous CRCs) enrolled in three randomized trials, evaluating infused FU as first-line treatment.RESULTS: Mucinous CRCs more frequently had high TOPO1 expression than did non-mucinous tumors (41% vs. 15%, p=0.028). The median overall survival was 14.2 months for patients with mucinous CRC with low TOPO1 expression compared with 9.7 months for high TOPO1-expressing cases (p=0.016). After adjusting for confounding variables, low TOPO1 expression was statistically favourably associated with overall survival (hazard ratio=0.55; p=0.041).CONCLUSION: Our data suggest the TOPO1 expression levels to be a prognostic marker in patients with mucinous CRC treated with FU. If further verified, these data might redefine therapeutic strategies by identifying categories of patients with a worse prognosis.

We report the preliminary description of recent discoveries of Pliocene marine fauna from Arcille (Grosseto, Italy) and application of Ground Penetrating Radar to locate fossil vertebrate. During the past years four partially articulated sirenian skeletons were found in shallow siliciclastic deposits exposed in the Arcille area. All these fossil remains can be referred to Metaxytherium subapenninum, an extinct species of haliteriine dugongid (Mammalia, Sirenia) spread along the northwestern coasts of Mediterranean Basin and became extinct in the upper part of the Pliocene because of the progressive climatic cooling occurred after 3.1 Ma (Sorbi et al. 2008). Planktonic foraminiferal assemblages are consistent with an attribution of the sirenian specimens to the lower part of the Zanclean, in particular to the MPl2 zone of Cita (1975) dated between 5.08 and 4.52 Ma (age after Lourens et al., 2004). Three specimens were collected in a sand quarry and one of this is almost complete. The fourth specimen, discovered in a sunflower field near the quarry, was collected as a consequence of a preliminary georadar prospection. This technique is a non destructive method based on propagation and reflection of electromagnetic (EM) waves and it is sensitive to variations of the EM parameters in the subsoil, especially the dielectric constant and electric conductivity (Davis and Annan, 1989). The GPR survey was performed using the Radar System device of IDS Company, equipped with a monostatic antenna of 200 MHz. Two adjacent areas have been mapped. Time slices at various depths indicated the presence of several reflective zones: one of this was located at the centre of the first area at 0.20 m from surface. The other zones were smaller and not persistent and rapidly changing in shape with depth. In the second area, two small zones were recorded. We decided to verify the nature of this GPR signals through an excavation. In corrispondance with the central reflective zone of the first area, some fossil bones emerged: in particular, the skull with tusks, the mandibles with teeth, some cervical and dorsal vertebrae and a considerable number of ribs. Other bones (humerus, radius and scapula) were found in correspondance with smaller reflective zones of the same area. In the second area, we discovered several caudal vertebrae in correspondence of one of the two reflective zones. The results obtained from this study are very interesting, although further experimentations are required for a better refinement of this surveying method for paleontological research. Cita M. B. (1975). Studi sul Pliocene e sugli strati di passaggio del Miocene al Pliocene. VIII. Planktonic foraminiferal biozonation of the Mediterranean Pliocene deep sea record. A revision. Rivista Italiana di Paleontologia e Stratigrafia 81, pp. 527-544. Davis J. L., Annan A. P. (1989). Ground Penetrating Radar for high-resolution mapping of soil and rock stratigraphy. Geophysical Prospecting, 37, 531-551. Lourens L. J., Hilgen F. J., Laskar J., Shackleton N.J., Wilson D. (2004). Appendix 2. Orbital tuning calibrations and conversions for the Neogene period, pp. 469―484 in: F. Gradstein, J. Ogg, and A. Smith (eds), A Geologic Time Scale (2004). Cambridge University Press, Cambridge. Sorbi S., Vaiani S. C., Bianucci G. (2008). Metaxytherium subapenninum: l’ultimo sirenio del Mediterraneo. Giornate di Paleontologia VIII edizione, Simposio della Società Paleontologica Italiana (Siena, 2008), pp. 97-99.