Search

The Maps of Geohazard features of the Western Sardinia produced by the Magic project (MArine Geohazard along Italian Coasts) were presented. The maps were created using morphobathymetric data obtained by surveying with a multi-beam echo sounder. The main potential geo-hazards on the western Sardinian margin are related with the presence of three pockmark fields which include hundreds of elements from few meters to several hundred meters in diameter. The pockmark fields are located ~25-35 km off the coastline and at more than 400 m depth. [ABSTRACT FROM AUTHOR]

The generation and conduction state of breakdown spot patterns in HfO2-based metal-insulatormetal structures are investigated using transient infrared thermography in combination with spatial statistics. The spots are created at a low generation rate by applying an appropriate constant voltage stress to the devices. Because of the important thermal effects involved during degradation, the breakdown events leave their fingerprints on the top metal electrode in the form of two-dimensional point patterns. Contrary to what is expected, thermal mappings reveal that many of these failure sites do not longer conduct after their creation, which is consistent with a self-healing behavior. In order to investigate whether the local heat dissipation and thermal propagation induce spatial correlation among the failure events or not, the final breakdown spot spatial distributions are compared with simulations of homogeneous Poisson point processes in the plane and the results are validated against the smoothed residual field and quantile-quantile plots. [ABSTRACT FROM AUTHOR]

The evolution of coastal and transitional environments depends upon the interplay of human activities and natural drivers, two factors that are strongly connected and many times conflicting. The urge for efficient tools for characterising and predicting the behaviour of such systems is nowadays particularly pressing, especially under the effects of a changing climate, and requires a deeper understanding of the connections among different drivers and different scales. To this aim, the present paper reviews the results of a set of interdisciplinary and coordinated experiences carried out in the Adriatic Sea (north-eastern Mediterranean region), discussing state-of-the art methods for coastal dynamics assessment and monitoring, and suggests strategies towards a more efficient coastal management. Coupled with detailed geomorphological information, the methodologies currently available for evaluating the different components of relative sea level rise facilitate a first identification of the flooding hazard in coastal areas, providing a fundamental element for the prioritization and identification of the sustainability of possible interventions and policies. In addition, hydro- and morpho-dynamic models are achieving significant advances in terms of spatial resolution and physical insight, also in a climatological context, improving the description of the interactions between meteo-oceanographic processes at the regional scale to coastal dynamics at the local scale. We point out that a coordinated use of the described tools should be promptly promoted in the design of survey and monitoring activities as well as in the exploitation of already collected data. Moreover, expected benefits from this strategy include the production of services and infrastructures for coastal protection with a focus on short-term forecast and rapid response, enabling the implementation of an event-oriented sampling strategy. [ABSTRACT FROM AUTHOR]

Background: Sub-Sahara Africa hosts up to 71 % of all HIV infected people in the world. With this high incidence of Human immunodeficiency virus ( HIV) comes the burden of co-morbidities such as malignant and premalignant lesions. Aids defining malignancies have been listed as Kaposi's sarcoma, Non-Hodgkin's lymphoma and invasive squamous cell carcinoma of the cervix. People with HIV/AIDS(PLWAS) have a higher risk of developing these neoplasms than the rest of the population. The pathogenesis of these neoplasms in people with HIV has been linked to immune suppression, persistent antigenic stimulation and cytokine dysregulation. Current study analyzes and presents the patterns and trends in the presentation of HIV related malignancies in patients diagnosed through histopathology at Kenyatta National Hospital. Aim: To describe the patterns of AIDS- defining and non-AIDS- defining malignancies and premalignant lesions 10 years pre- and post HAART period at Kenyatta National hospital, Kenya. Methods and techniques: This was a hospital based descriptive cross sectional study. The Formalin fixed paraffin embedded (FFPE) blocks and histological reports of patients diagnosed between 2000 and 2011 were traced from archives. The patients' demographic data and clinical presentation was entered in an excel spreadsheet and the diagnosis and coding confirmed by a histopathologist. The data was then cleaned and analyzed using SSPS version 17.0 Ink. Results: A total of 173 lesions were reviewed and analyzed. Of these 118 (68 %) were from females and 55 from males (32 %). The male to female ratio was 1:2. The age range was from two to 56 years with a median of 36 years. Kaposi sarcoma is the leading AIDS defining malignancy in Kenya while invasive squamous cell carcinoma of the conjunctiva is the leading non-AIDS defining malignancy. This is closely followed by invasive squamous cell carcinoma of the cervix and NHL. Conclusion: Kaposi sarcoma is the leading AIDS associated neoplasm in Kenya. Physicians and caretakers managing and following up on HIV/AIDS patients should look out for Kaposi sarcoma as a form of IRIS following the institution of HAART in all HIV/AIDS patients. The incidence of invasive squamous cell carcinoma of the conjunctiva is increasing in PLWAS in Kenya. There is therefore a need to introduce early screening programs for squamous intraepithelial neoplasm of the conjunctiva in HIV/AIDS patients. [ABSTRACT FROM AUTHOR]

The presence and distribution of harmful algal species were investigated along the coasts of Sardinia in the summer of 2012. Fourteen potentially noxious taxa were identified at 74 beaches. The majority of the recovered taxa were potentially toxic and/or high biomass producers.Alexandrium taylorii,Gymnodinium instriatum, andOstreopsiscf.ovatawere the most frequent and abundant taxa, althoughBarrufeta bravensisreached the highest density (4.4 × 106cells L−1).Barrufeta bravensis,A. taylorii, andG. instriatumwere responsible for intense water discoloration at two of the beaches sampled. Polymerase chain reaction (PCR) analyses supported the identification of several taxa and decisively identifiedB. bravensis. PCR assays increased the information available on the species distributions. The locations studied were heterogeneous in their prevailing environmental conditions and their morphodynamic profiles. Statistical analyses indicated that the distributions of harmful algal species correlated with gravel and medium-fine sand substrata. These data provide substantial knowledge on the distributions of harmful algal species on beaches, which have been poorly studied on a global scale. The apparent relationship between noxious species and grain size suggests that vegetative cells may be recruited from cyst beds in beach sediments. [ABSTRACT FROM AUTHOR]

The effect of ethanol addition in ethylene laminar premixed flames on the characteristics of soot precursor nanoparticles was investigated by aerosol photoionization technique. The fifth harmonic of a Nd:YAG laser, 213 nm (5.82 eV), was used as ionization source, while a differential mobility analyzer (DMA) coupled to a Faraday cup electrometer was used for ionized particle classification and detection. Carbonaceous nanoparticles in the nucleation mode, i.e., with sizes ranging from 1 to 10 nm, show a photoionization charging efficiency clearly dependent on the percentage of ethanol used as dopant in the flame. In particular, we observed that the more ethanol was added as fuel, the lower the particle photo-charging efficiency was. This result indicates a modification in the nanoparticle chemical structure as the amount of ethanol is increased. These experimental evidences may be explained by a decrease of aromaticity of the particles and/or by the presence of oxygen bonds within the nanoparticles. [ABSTRACT FROM PUBLISHER]

Sporadic Burkitt lymphoma (sBL) can be delineated from diffuse large B-cell lymphoma (DLBCL) by a very homogeneous mRNA expression signature. However, it remained unclear whether all three BL variants-sBL, endemic BL (eBL) and human immunodeficiency virus-associated BL (HIV-BL)-represent a uniform biological entity despite their differences in geographical occurrence, association with immunodeficiency and/or incidence of Epstein-Barr virus (EBV) infection. To address this issue, we generated micro RNA (miRNA) profiles from 18 eBL, 31 sBL and 15 HIV-BL cases. In addition, we analyzed the miRNA expression of 86 DLBCL to determine whether miRNA profiles recapitulate the molecular differences between BL and DLBCL evidenced by mRNA profiling. A signature of 38 miRNAs containing MYC regulated and nuclear factor-kB pathway-associated miRNAs was obtained that differentiated BL from DLBCL. The miRNA profiles of sBL and eBL displayed only six differentially expressed miRNAs, whereas HIV and EBV infection had no impact on the miRNA profile of BL. In conclusion, miRNA profiling confirms that BL and DLBCL represent distinct lymphoma categories and demonstrates that the three BL variants are representatives of the same biological entity with only marginal miRNA expression differences between eBL and sBL. [ABSTRACT FROM AUTHOR]

A comparative study was performed of three instruments used to measure the grain-size distribution of thirty sediment samples from shallow lagoonal flats: the hydrometer, the Sedigraph 5100 and the CIS-1. The hydrometer and Sedigraph are based on sedimentation whereas the CIS-1 uses the time of transition. The percentage of the samples accounted for by the <8 μm fraction was not affected by the technique used, but this was not the case with the clay fraction (<2 μm). Due to its relative independence from the analytical method applied, the <8 μm fraction can be used in ternary diagram classifications. This fraction also has an environmental significance in coastal lagoons in terms of hydrodynamics, organic enrichment and macrozoobenthos assemblages. The linear relationships obtained in this study may provide useful operational indications for similar studies. [ABSTRACT FROM AUTHOR]

Marine cage aquaculture has the potential to severely impact Posidonia oceanica seagrass meadows and its associated fauna. In order to assess the impact of fish farming in a littoral bay of Corsica, France, physico-chemical (mud and organic matter) and biological (density and compactness of P. oceanica beds and associated macrofauna) variables have been examined in two stations putatively impacted to different degrees (St1 and St2) and in two unimpacted stations (Controls: C1 and C2). Principal Component Analysis of meadow structural variables (shoot density and compactness of matte) and abiotic variables (mud and organic matter percentage into sediment) highlighted differences among stations and, particularly, differences between impacted stations and controls. Results from C1 and C2 totally overlapped. St1 was the station which differed the most from controls. Compared with control stations, St1 and St2 were characterized by higher values of organic matter and mud and by lower values of shoot density and matte compactness. Permutational multivariate analysis of variance (PERMANOVA) did not show significant differences between C1 and C2 in the structure of macrofauna assemblages, whereas significant differences between the two impacted sites and between these and the control conditions emerged. Differences in assemblages were well correlated with the measured abiotic variables. The analysis showed that the species most responsible for difference among stations were typical of muddy sediment with high organic matter content. These species had higher mean abundance values at impacted stations than at controls. This study suggests fish farming determines an increase of organic matter and sedimentation, which resolve in changes in structural properties of the seagrass meadows and, consequently, changes in the associated macrofauna assemblages. [ABSTRACT FROM AUTHOR]

The molecular feature of Burkitt lymphoma (BL) is the translocation that places c-Myc under the control of immunoglobulin gene regulatory elements. However, there is accumulating evidence that some cases may lack an identifiable MYC translocation. In addition, during the EUROFISH project, aiming at the standardization of FISH procedures in lymphoma diagnosis, we found that five cases out of 35 classic endemic BLs were negative for MYC translocations by using a split-signal as well as a dual-fusion probe. Here we investigated the expression pattern of miRNAs predicted to target c-Myc, in BL cases, to clarify whether alternative pathogenetic mechanisms may be responsible for lymphomagenesis in cases lacking the MYC translocation. miRNAs are a class of small RNAs that are able to regulate gene expression at the post-transcriptional level. Several studies have reported their involvement in cancer and their association with fragile sites in the genome. They have also been shown to control cell growth, differentiation, and apoptosis, suggesting that these molecules could act as tumour suppressors or oncogenes. Our results demonstrated a modulation of specific miRNAs. In particular, down-regulation of hsa-let-7c was observed in BL cases, compared to normal controls. More interestingly, hsa-mir-34b was found to be down-regulated only in BL cases that were negative for MYC translocation, suggesting that this event might be responsible for c-Myc deregulation in such cases. This hypothesis was further confirmed by our in vitro experiments, which demonstrated that increasing doses of synthetic hsa-mir-34b were able to modulate c-Myc expression. These results indicate for the first time that hsa-mir-34b may influence c-Myc expression in Burkitt lymphoma as the more common aberrant control exercised by the immunoglobulin enhancer locus. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Angiogenic switch marks the beginning of tumor’s strategy to acquire independent blood supply. In some subtypes of non-Hodgkin’s lymphomas, higher local vascular endothelial growth factor (VEGF) expression correlates with increased microvessel density. However, this local VEGF expression is higher only in tumors with elevated expression of the receptors of the growth factor, suggesting an autocrine growth-promoting feedback loop. Several studies have indicated that VEGF receptors are also targeted by Tat protein from the HIV-1-infected cells. Given the similarity of the basic region of Tat to the angiogenic factors (basic fibroblast growth factor, VEGF), Tat mimics these proteins and binds to their receptors. We evaluated the role of HIV-1 Tat in regulating the level of VEGF expression and microvessel density in the AIDS-related diffuse large B-cell (DLBCL) and Burkitt lymphomas (BL). By luciferase assay, we showed that VEGF promoter activity was downregulated in vitro in cells transfected with Tat. Reduced VEGF protein expression in primary HIV-1 positive BL and DLBCL, compared to the negative cases, supported the findings of promoter downregulation from the cell lines. Microvascular density assessed by CD34 expression was, however, higher in HIV-1 positive than in HIV-1 negative tumors. These results suggest that Tat has a wider angiogenic role, besides the regulation of VEGF expression. Thus, targeting Tat protein itself and stabilizing transient silencing of VEGF expression or use of monoclonal antibodies against their receptors in the AIDS-associated tumors will open a window for future explorable pathways in the management of angiogenic phenotypes in the AIDS-associated non-Hodgkin’s lymphomas. [ABSTRACT FROM AUTHOR]

We investigated macrofaunal species richness and composition in Posidonia oceanica, Cymodocea nodosa and Leaf litter beds within a coastal area of the Gulf of Oristano in proximity of the Cabras lagoon (western Sardinia, Italy). A total of 124 taxa were found, of which 116 were identified at the species level. They were analyzed based on both taxonomic and substrate affinity classification. Presence/absence analysis revealed that P. oceanica, C. nodosa and Leaf litter were all characterized by a conspicuous number of soft-bottom polychaetes (e.g., Prionospio multibranchiata and Ampharete acutifrons) and crustaceans (e.g., Corophium sextonae and Dynamene bidentatus), also known as detritivores. There were also major differences between the three habitats investigated. Consistent with its structural complexity, P. oceanica showed the highest species richness [ E( S 50)] and the most diversified macrofaunal assemblages, both in terms of taxonomic groups and taxa associated with different substrates. The two seagrasses, however, showed a similar species composition and differed from Leaf litter for the exclusive presence of hard-bottom species (e.g., the tunicate Phallusia fumigata) and seagrass-associated species (e.g., the polychaete Syllis garciai and the decapod Paguristes syrtensis). In contrast, Leaf litter showed the most differences between the habitats, and was characterized by the bivalves Abra alba and Cerastoderma glaucum, not found in seagrass beds, and by Loripes lacteus and Ruditapes decussatus. Leaf litter also had the highest content of organic matter (26.7% ± 1.4) and total organic carbon (10.3% ± 0.4). Our results confirmed the facilitative role of living seagrasses, in particular P. oceanica, as related to their structural complexity, for numerous species from different substrates (e.g., hard bottom species). This study also showed that leaf litter beds act as a particular environment where sediment instability, leaf breakdown, and organic matter enrichment and decomposition strongly influence animal distribution. Finally, our results highlighted the ecological and trophic importance of seagrass-derived detritus and the associated macroinvertebrate detritivores within seagrass-dominated systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Coastal Research is the property of KnowledgeWorks Global, Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Retinoblastoma is the most common primary intraocular tumor in childhood. Mutations in both the alleles of the RB1 gene represent the causative agent for the tumor to occur. It is becoming evident that, although these alterations represent key events in the genesis of retinoblastoma, they are not sufficient per se for the tumor to develop, and other additional genetic or epigenetic alterations must occur. A supportive role in the genesis of retinoblastoma has recently been proposed for the RB1-related gene RB2/p130. Additionally, several other genetic alterations involving different chromosomes have been described as relevant in the tumorigenic process. In this review we will analyse current knowledge about the molecular mechanisms involved in retinoblastoma, paying particular attention to the mechanisms of inactivation of the biological function of the retinoblastoma family of proteins.Oncogene (2006) 25, 5333–5340. doi:10.1038/sj.onc.1209614 [ABSTRACT FROM AUTHOR]

It appears more and more clear that retinoblastoma (RB) family of proteins represents key molecules in tumour suppression. This family consists of pRb/p105, p107 and pRb2/p130, which participate in a gene regulatory network that governs the cellular response to antimitogenic signals, and whose deregulation constitutes one of the hallmarks of cancer. Irrespective of their structural and biochemical similarities, RB proteins carry out different functional tasks. The expression of RB gene family in the reactive lymphoid tissues again confirms the different role of each member in cell cycle control and differentiation of normal cells. These different functional properties appear to be maintained in tumours lymphoid tissues, where alterations of the RB/p105 gene appear to be relatively rare. In this review, we will summarize the current knowledge about the role of the RB proteins in reactive and neoplastic lymphoid tissue.Oncogene (2006) 25, 5309–5314. doi:10.1038/sj.onc.1209619 [ABSTRACT FROM AUTHOR]

The protein product of the retinoblastoma (RB) gene is necessary for the completion of the muscle differentiation program and for myogenic basic helix–loop–helix-dependent transcription. In fact, in addition to induction and maintenance of permanent cell cycle withdrawal through negative regulation of E2F-responsive genes involved in proliferation, pRb also plays a positive role in the activation of muscle-specific genes. In pRb−/− myocytes, the expression of late myogenic markers is defective and myoblast fusion into myotubes occurs without irreversible cell cycle exit. This evidence demonstrates only a partial functional redundancy between pRb and its relatives p107 and pRb2/p130, as these pRb−/− multinucleated cells, which display p107 levels higher than normal myotubes, respond to mitogens with cell cycle re-entry and DNA synthesis. At the molecular level, pRb myogenic functions are mediated by cooperation with MyoD, Myocyte enhancer factor 2 (MEF2), High mobility group box protein-1 (HBP1) and histone deacetylase1, affecting chromatin configuration and tissue-specific transcription, and by post-translational modification in response to intracellular signaling cascades.Oncogene (2006) 25, 5244–5249. doi:10.1038/sj.onc.1209623 [ABSTRACT FROM AUTHOR]

Human polyomaviruses (JC virus, BK virus and simian virus 40) are causative agents of some human diseases and, interestingly, are involved in processes of cell transformation and oncogenesis. These viruses need the cell cycle machinery of the host cell to complete their replication; so they evolved mechanisms that can interfere with the growth control of infected cells and force them into DNA replication. The retinoblastoma family of proteins (pRb), which includes pRb/p105, p107 and pRb2/p130, acts as one of the most important regulators of the G1/S transition of the cell cycle. Rb proteins represent an important target for viral oncoproteins. Early viral T antigens can bind all members of the pRb family, promoting the activation of the E2F family of transcription factors, thus inducing the expression of genes required for the entry to the S phase.The interaction between early viral antigens and cell cycle regulators represents an important mechanism through which viruses deregulate cell cycle and lead to cell transformation. In this review, we will discuss the effects of the interaction between large T antigen and Rb proteins in JC virus-mediated oncogenesis.Oncogene (2006) 25, 5294–5301. doi:10.1038/sj.onc.1209681 [ABSTRACT FROM AUTHOR]

Macrofaunal communities and specific bulk properties of organically enriched sediments were investigated in the coastal lagoon of Cabras (Sardinia, western Mediterranean) on a grid of twenty-nine sampling stations, in spring 2001. Species composition and community structure indicated poor and heterogeneous macrofaunal communities, characterized by few predominant taxa typical of degraded environments, such as Polydora ciliata, Tubificidae nc and Neanthes succinea, distributed differently in some areas of the lagoon. Sediments were homogeneously muddy, with a mean silt þ clay content of 93%. The analysis of specific grain size intervals within the mud fraction, however, highlighted a marked spatial variability of sediment particle distribution. Simple associations included a positive relationship of both Ficopomatus enigmaticus and Corophium sextonae, patchily distributed along the shores, with sediment sorting (σ), an index of sediment selection due to hydrodynamic energy. By contrast, inner areas, characterized by a major accumulation of finer particles (and organic matter), with a sediment mean size (Φ) up to 8.2 phi, were least populated. The results suggest the existence of an early stage of faunal succession which might be related to an excessive organic content of sediments and the tendency to dystrophic events in the Cabras lagoon. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the spatial variability of sediment bulk properties in the surface sediments as well as down-core trends, and to assess the relationship between sediment distribution and levels of total organic carbon (TOC), in the Cabras lagoon, Sardinia. Grain size distributions and TOC contents were measured in the surface sediments (0–2 cm horizon) in a grid of 31 stations. Vertical profiles along the 0–24 cm depth horizon were also measured in three stations. In the superficial horizon, TOC content was very high, up to 43 mg g-1 , with a mean of 33 mg g-1 . Core profiles showed a marked reduction of TOC content with depth to ∼20–25 mg g-1 and a concomitant shift in particles size towards a sandier composition (mud content decreasing from 95–100% to 70–85%) at 3–7 cm core depth. Total organic carbon contents in the uppermost layers were associated with the grain size fraction <8 μm. The results suggest that a major change in the sedimentary regime of the lagoon, associated with internal trapping and re-distribution of organic C-bounding fine particles, has been occurring in the last few decades. The cause would appear to be the construction of a dam at the lagoon mouth rising up to the high tide level in order to maintain a constant lagoonal water level. [ABSTRACT FROM AUTHOR]

The World Health Organisation classification reports three subcategories of Burkitt's lymphoma (BL)—endemic, non-endemic, and immunodeficiency associated-proposed to reflect the major clinical and genetic subtypes of this disease. These different types of BL have been reviewed and studied by immunohistochemistry and molecular methods. The results point out the heterogeneity of BL and suggest that AIDS related BL may have a different pathogenesis from that of classic BL. [ABSTRACT FROM AUTHOR]

Relationships between sedimentary features and the distribution and structure of Posidonia oceanica meadows were investigated in the Gulf of Oristano (Sardinia) in a study site stretching from the mouth of the Tirso River in a more sheltered, inner sector of the gulf to an outer, more exposed sector near the rocky Cape San Marco. The results demonstrate that gradients in sediment texture and composition can be related to meadow distribution and areal coverage. We suggest that this involves the mechanical trapping of fine particles by the plants, enhanced mud deposition due to dampening of wave action in the meadows, and the admixture of bioclastic sediments linked to increased production by epiphytes and invertebrates. Independent evidence of seagrass erosion was recorded in an unvegetated breach in the meadow. The mass of fine sediment which would be resuspended in the wake of meadow destruction was estimated at 30–90 × 103 tonnes km−2, an amount which could substantially influence water quality and ecosystem stability in the gulf. [ABSTRACT FROM AUTHOR]