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Abstract Loss of algal canopies can result in a shift towards a turf-dominated state, where variability in species life-history traits can determine new mechanisms of feedback, and influence the degraded system under variable regimes of disturbance. By focusing on rockpools dominated by Cystoseira brachycarpa , we tested the hypothesis that the alga Dictyopteris polypodioides could take advantage of extreme regimes of disturbance related to storms, and outcompete other turfs through a distinctive combination of life traits. Replacement of the canopy was initially driven by a mix of taxon-specific life-traits and resulting assemblages were susceptible to intense events of disturbance. Subsequently, D. polypodioides dominated removal quadrats, favored by density-dependent abilities to intercept more light and reach larger size than the rest of turf. These new positive feedbacks may contribute to maintain the modified state of the system and influence its ability to withstand extreme abiotic conditions. Highlights • Replacement of Cystoseira by turf was initially driven by a mix of taxon-specific life-traits. • Turf-dominated assemblages were influenced by intense events of disturbance. • On a longer time scale, Dictyopteris polypodioides outcompeted other turf algae. • Dominance of D. polypodioides established new feedback mechanisms in the system. [ABSTRACT FROM AUTHOR]

Summary: The success of MPAs in conserving fishing resources and protecting marine biodiversity relies strongly on how well they meet their planned (or implicit) management goals. From a review of empirical studies aiming at assessing the ecological effects of Mediterranean and Macaronesian MPAs, we conclude that establishing an MPA is successful for (i) increasing the abundance/biomass, (ii) increasing the proportion of larger/older individuals, and (iii) enhancing the fecundity of commercially harvested populations; also, MPAs demonstrated to be effective for (iv) augmenting local fishery yields through biomass exportation from the protected area, and (v) inducing shifts in fish assemblage structure by increasing the dominance of large predator species. However, the attraction for tourism and diving due to ecological benefits of protection can cause damages likely to reverse some of the MPA effects. Other expected effects are more subject to uncertainty, and hence need more research, such as (vi) causing density-dependent changes in life history traits and (vii) protecting the recruitment of commercially important species, (viii) protecting marine biodiversity (including genetic diversity), (ix) causing ecosystem-wide effects such as trophic cascades, and (x) increasing community and ecosystem stability, thus promoting resilience and faster recovery from disturbance. Meta-analysis of data arising from these case studies are used to establish the overall effect of MPAs, and its relationship to MPA features, such as size of no-take area or time since protection. Based on the review and the meta-analyses, specific recommendations are provided for MPA management, regarding the establishment of goals and objectives, site selection, MPA design and zoning, planning, and monitoring. Finally, a series of recommendations for MPA research are offered to drive future research in MPA issues in the Mediterranean and Macaronesia. [Copyright &y& Elsevier]

Objective: Proliferation and chondrogenic commitment of cultured articular chondrocytes are impaired when cells derive from aged donors. In those subjects the feasibility of cell-based therapies for articular surface repair is reduced. Moreover, the use of serum as medium supplement elicits non-physiological responses in cultured chondrocytes. This study was therefore undertaken to identify the expansion culture conditions needed to sustain growth and chondrogenic commitment of chondrocytes harvested from aged human subjects.Design: Articular cartilage was obtained from aged (69-75 years) and from young adult subjects (27-35 years). Chondrocytes were isolated and cultured in serum-free (SF) or in serum-supplemented [fetal calf serum (FCS)] conditions. Chondrocytes were expanded in monolayer for five duplications and processed for RNA extraction and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. The differentiation potential was assessed by micromass pellet cultures before and after expansion in either culture medium, or after a prolonged exposure to serum followed by a period in SF condition.Results: Only SF-cultured chondrocytes reached five duplications within 25-35 days, maintaining the expression of some chondrogenic markers and without altering the levels of active matrix metalloproteinase 3 (MMP-3). Only the pellets derived from SF-expanded cultures positively stained for cartilage matrix deposition. On the contrary, exposure to serum diminished the proliferation capacities, abolished the differentiation potential in the same cells and elicited transcription of the MMP-3 gene. Shifting culture conditions from FCS to SF resumed growth rates but proper extracellular matrix deposition was only partially restored.Conclusions: The SF conditions have proven valuable to prime cell proliferation and to sustain proper commitment in chondrocytes from aged patients. This culturing approach may represent a therapeutic chance extendable to a range of patients normally excluded from clinical protocols based on autologous chondrocyte implantation (ACI). [ABSTRACT FROM AUTHOR]

Insular assemblages of species are often considered unique because they are exposed to unpredictable patterns of colonization/extinction that depend on distance from other sources of colonists and on size of islands. An alternative explanation is that islands provide fundamentally different habitats of those of the mainland, regardless of any possible effect of size and isolation. These alternatives were examined by comparing assemblages of rocky shores on islands of the Tuscany Archipelago with those of the mainland in the same geographical region. Sandy beaches created a pattern of discrete areas of rock along the mainland with spatial discontinuities and extents comparable to those of the insular environment. Possible effects of isolation and size were therefore controlled in this study, so that one would expect no difference between islands and the mainland if only size and isolation matter. In contrast, differences are expected if historical events or other processes have distinct influences on assemblages in these environments. These hypotheses were tested by comparing assemblages of midshore and lowshore habitats of two islands with those of two similarly distributed locations on the mainland over a period of 2 years, using a hierarchical sampling design. Multivariate and univariate analyses revealed various patterns in the data. There were differences between islands and the mainland in structure of assemblages, in mean abundance of common taxa and in the magnitude of spatial and temporal variance in abundance in both habitats. Collectively, these findings support the model that islands in the Tuscany Archipelago have distinct assemblages from the mainland, thereby contributing to the regional diversity and complexity of assemblages of rocky shores over and above any possible effect of size or isolation. [Copyright &y& Elsevier]

We analysed the immunophenotypic and molecular expression of BCA-1 (B-cell-specific chemokine) and CXCR5 (BCA-1 receptor) in normal skin and different cutaneous lymphoproliferative disorders (cutaneous T-cell lymphoma (CTCL); cutaneous B-cell lymphoma (CBCL); cutaneous B-cell pseudolymphoma (PCBCL)), with the aim of investigating their possible involvement in the pathogenesis of cutaneous B-cell disorders. BCA-1 and CXCR5 were constantly expressed in CBCL and PCBCL, but not in normal skin and CTCL. BCA-1 and CXCR5 were constantly coexpressed by CD22+ B-cells, while CD35+ follicular dendritic cells coexpressed BCA-1 in PCBCL cells only. In low grade CBCL, as compared with high grade CBCL, the intensity of CXCR5 expression on neoplastic CD22+ cells was lower than that of BCA-1. The image analysis of reverse transcriptase-polymerase chain reaction (RT-PCR) products showed a significant quantitative difference between PCBCL/low grade CBCL and high grade CBCL. The above findings, although only observed in a small series of patients, are in keeping with findings in MALT gastric and gastric MALT lymphomas, adding further evidence of the close similarities between CBCL and MALT lymphomas. [Copyright &y& Elsevier]

Marine protected areas (MPAs) are increasingly used as a management tool to preserve species and habitats. Testing hypotheses about the effectiveness of MPAs is important for their implementation and to identify informative criteria to support management decisions. This study tested the general proposition that MPAs affected assemblages of algae and invertebrates between 0.0 and 0.5 m above the mean low water level of rocky coasts on two islands in the Tuscan Archipelago (northwest Mediterranean). Protection was concentrated mainly on the west coasts of the islands, raising the possibility that neither the full range of assemblages nor the relevant scales of variation were properly represented within MPAs. This motivated the comparison of assemblages on opposite sides of islands (habitats). The effects of MPAs and habitat were assessed with a multifactorial sampling design; hypotheses were tested about differences in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation. The design consisted of three replicate shores for each condition of protected and reference areas on the west side of each island and three unprotected shores on the eastern side. Assemblages were sampled independently four times on each island between June 1999 and January 2001. At each time of sampling two sites were selected randomly at each of two tidal heights to represent midshore and lowshore assemblages on each shore. Estimates of abundance were obtained using non-destructive sampling methods from five replicate 20×20 cm quadrats at each site. Results indicated differences among habitats in structure of assemblages, in mean abundance of common taxa and in univariate and multivariate measures of spatial variation at the scale of shores. Most of these patterns were inconsistent with the predicted effect of management through MPAs. The data suggest that designation of MPAs in the Tuscan Archipelago should proceed through management of multiple shores and types of habitat selected to guarantee protection to a representative sample of assemblages and to the processes responsible for maintenance of spatial patchiness at different scales. This study also shows that considerations of spatial heterogeneity are important to underpin management decisions about the number, size and location of MPAs. [Copyright &y& Elsevier]

Inflammation plays a crucial role in Alzheimer's disease (AD). AD neurodegeneration and concurrent involvement of the peripheral immune system may promote leukocyte division and telomere shortening. We examined genotypes and plasma levels of two proinflammatory cytokines, IL-1beta and IL-18, and leukocyte telomere length (LTL) in patients with mild cognitive impairment (MCI) and AD. We wanted to determine whether changes in plasma IL-1beta and IL-18 levels, together with LTL shortening, could be diagnostic for disease progression from MCI to AD. Median plasma IL-1beta levels were in the order MCI patients (2.2 pg/ml) < AD patients (4.0 pg/ml), both of which differed significantly from the controls (0.0 pg/ml). In the AD patients, the lowest IL-1beta levels were associated with the presence of the C allele of IL-1beta rs16944 SNP. Median plasma IL-18 levels were in the order MCI patients (116.3 pg/ml) > AD patients (85.8 pg/ml), both of which were significantly higher than in the controls (17.6 pg/ml). Analysis of LTL showed a progressive reduction in the order controls > MCI > AD patients (p < 0.0001). Overall LTL reduction was correlated with increased plasma IL-1beta levels, substantiating the hypothesis that inflammatory processes secondary to neuroinflammation may trigger telomere attrition. Changes in plasma IL-1beta and Il-18 levels, and LTL seem to reflect shifts in AD stage; they may have potential use as blood biomarkers to monitor disease onset and progression from MCI to AD. • Changes of plasma IL-1beta and IL-18 levels in AD and MCI patients were investigated. • Both interleukins had a distinctive behavior in the MCI group. • LTL in MCI group showed intermediate values between controls and AD groups. • LTL reduction was correlated with increased plasma IL-1beta levels. • Changes in serum IL-1beta and Il-18 levels and LTL seem to reflect shifts in AD stage. [ABSTRACT FROM AUTHOR]