Type A Aortic Dissection Masquerading as an Inferior Myocardial Infarction.

Type A aortic dissection is a life-threatening condition with a wide range of clinical manifestations. Dissection can sometimes mimic an acute myocardial infarction due to similar presenting symptoms and initial clinical investigations. We report the case of a 52-year-old male who presented with an inferior ST-segment elevation myocardial infarction with two drug-eluting stents inserted as a stabilizing intervention prior to surgical repair of an acute aortic dissection.

Microbial communities of polyhydroxyalkanoate (PHA)-based biodegradable composites plastisphere and of surrounding environmental matrix: a comparison between marine (seabed) and coastal sediments (dune sand) over a long-time scale.

Most researches on the plastisphere in coastal environments deal with plastics floating in seawater. Comparatively smaller attention has been devoted to the plastisphere of plastics buried in marine sediments, and very little is known on that of plastics on coastal sand dunes. Yet, limited information is available on the impact of plastics, especially biodegradable plastics, on microbial organisms in their surroundings. Nevertheless, a large amount of plastics sink on the seabed or is deposited on beach-dune systems. We investigated the succession of plastisphere microbial community on two biodegradable composites based on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and seagrass fibres (PHBV/PO), buried in seabed and dune sediments over a 27 months period in mesocosm. PHBV is regarded as a valuable alternative to conventional plastics and PHBV/PO has recently been designed for applications in coastal habitat restoration. We also examined the degradation rate and impact of these plastics on the microbial communities of surrounding sediments. Microbial communities of the surface of PHBV and PHBV/PO in seabed and dune sand differ from those of surrounding sediments, displaying a lower richness. Plastics colonization occurs largely from bacteria present in surrounding sediments, although the contribution from the water column bacterial pool could be not negligible for plastics in the seabed. No significant differences were detected between the communities of the two plastics and no significant impact of plastics on microbial community of the surrounding sediments was detected. The exceptional long duration of this study allowed to gain information on the succession of a plastisphere community over a previously unexplored time scale. Succession appears highly dynamic in dune sand even after two years, while the community structure in seabed seems to reach stability after one year. These findings highlight the importance of performing long-term studies when trying to characterize composition and dynamics of plastisphere bacterial communities.

Detecting Associations Between Ciliated Protists and Prokaryotes with Culture-Independent Single-Cell Microbiomics: a Proof-of-Concept Study.

Symbioses between prokaryotes and microbial eukaryotes, particularly ciliated protists, have been studied for a long time. Nevertheless, researchers have focused only on a few host genera and species, mainly due to difficulties in cultivating the hosts, and usually have considered a single symbiont at a time. Here, we present a pilot study using a single-cell microbiomic approach to circumvent these issues. Unicellular ciliate isolation followed by simultaneous amplification of eukaryotic and prokaryotic markers was used. Our preliminary test gave reliable and satisfactory results both on samples collected from different habitats (marine and freshwater) and on ciliates belonging to different taxonomic groups. Results suggest that, as already assessed for many macro-organisms like plants and metazoans, ciliated protists harbor distinct microbiomes. The applied approach detected new potential symbionts as well as new hosts for previously described ones, with relatively low time and cost effort and without culturing. When further developed, single-cell microbiomics for ciliates could be applied to a large number of studies aiming to unravel the evolutionary and ecological meaning of these symbiotic systems.

Novel Sustainable Composites Based on Poly(hydroxybutyrate-co-hydroxyvalerate) and Seagrass Beach-CAST Fibers: Performance and Degradability in Marine Environments.

In order to produce sustainable, bio-based and highly biodegradable materials, composites based on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and fibers of Posidonia oceanica (PO), a dominant Mediterranean seagrass, were produced by simple melt mixing and characterized in terms of thermal stability, morphology and rheological/mechanical properties. In view of their potential application in marine environments, degradation of the developed composites was evaluated under simulated and real marine environmental conditions for 1 year. Using 10 wt % of acetyl tributyl citrate (ATBC) as a plasticizer, smooth processing was achieved for up to 30 wt % of PO fibers, despite the reduction of the melt fluidity observed with increasing fiber loading. The tensile modulus slightly increased (from 2 to 2.4 GPa) while the tensile strength and the elongation decreased (from 23.6 to 21.5 MPa and from 3.2 to 1.9%, respectively) by increasing the PO fiber content from 0 to 30 wt %. Interestingly, the impact resistance of the composites increased with the increasing of the PO content: the Charpy’s impact energy increased from 3.6 (without fiber) to 4.4 kJ/m² for the composite with 30 wt %. The results of the aerobic biodegradation under simulated marine conditions showed that the presence of PO fibers favored the physical disintegration of the composite increasing the biodegradation rate of the polymeric matrix: after 216 days, the composite with 20 wt % PO fibers showed a biodegradability of about 30% compared to 20% of the composite without fibers. Under real marine conditions, the specimens containing PO fibers showed higher weight losses and deterioration of tensile properties compared to those without fibers. Presumably, biodegradation occurred after colonization of the specimen, and the specimens with 20 wt % PO fibers showed well-developed biofilm consisting of bacteria and fungi on the surface after only 3 months of incubation in marine sediments, unlike the no-fiber specimens. Consequently, the persistence of an adequate mechanical performance for a relatively long period (1 year), due to a moderate rate of biodegradation in the marine environment, make the developed PHBV/PO composites particularly suitable for the production of relatively low-cost and biodegradable items which are usable in the sea and/or sand dunes, increasing the market opportunities for biopolymers such as PHBV and, at the same time, finding an eco-sustainable valorization for the PO fibrous residues accumulated in large quantities on Mediterranean beaches, which represents a problem for coastal municipalities.

Strengths and Biases of High-Throughput Sequencing Data in the Characterization of Freshwater Ciliate Microbiomes.

Molecular surveys of eukaryotic microbial communities employing high-throughput sequencing (HTS) techniques are rapidly supplanting traditional morphological approaches due to their larger data output and reduced bench work time. Here, we directly compare morphological and Illumina data obtained from the same samples, in an effort to characterize ciliate faunas from sediments in freshwater environments. We show how in silico processing affects the final outcome of our HTS analysis, providing evidence that quality filtering protocols strongly impact the number of predicted taxa, but not downstream conclusions such as biogeography patterns. We determine the abundance distribution of ciliates, showing that a small fraction of abundant taxa dominates read counts. At the same time, we advance reasons to believe that biases affecting HTS abundances may be significant enough to blur part of the underlying biological picture. We confirmed that the HTS approach detects many more taxa than morphological inspections, and highlight how the difference varies among taxonomic groups. Finally, we hypothesize that the two datasets actually correspond to different conceptions of "diversity," and consequently that neither is entirely superior to the other when investigating environmental protists.

Ciliate communities and hidden biodiversity in freshwater biotopes of the Pistoia province (Tuscany, Italy).

Ciliates are essential components of aquatic environments, playing a pivotal role in microbial loops. Thus, the composition and dynamics of ciliate communities have been subjected to intense studying. Morphological methods have been traditionally employed, until the development of next-generation sequencing recently allowed to explore the topic with exclusively molecular techniques. However, the results of the two approaches are hardly comparable, and the pictures they offer can be quite different. This may be due, among other reasons, to two factors: (1) morphological descriptions may miss a large portion of "hidden biodiversity" (including rare species and resistance forms) that is detected instead by molecular methods; (2) identification errors may arise due to difficulties in recognizing microbial taxa without in-depth analyses. In this survey of freshwater systems of the Pistoia province (Tuscany, Italy) we address both issues, trying to quantify the hidden diversity through prolonged observations of differentially treated sample aliquots, combining morphological identification with Sanger sequencing. We provide the first insights into the ciliate fauna of this area presenting results that are suitable for future comparisons thanks to their multidisciplinary origin, and supply the first molecular data on well-known taxa such as Linostomella and Disematostoma.

Demography and conservation of the Mediterranean fin whale (Balaenoptera physalus): what clues can be obtained from photo-identification data.

Long-lived and slow reproducing species, such as cetaceans, are among the most critical conservation units: a demographic approach can be very useful for their management and conservation. In the present work, we examined, by demographic tools, the most exhaustive photo-identification database available for the Mediterranean fin whale (Balaenoptera physalus) population, recorded by Tethys Research Institute between 1990 and 2007 in the Western Ligurian Sea. A total of 31,782 km were covered and 548 fin whale sightings were recorded. The occurrence of the target species was uneven across the years and months: an anomalous reduction of sightings occurred between 2001 and 2004. Moreover, the target species is likely to concentrate in the study area in the summer months and probably moves to other areas in the early autumn. Using the photo-identification technique, 431 different individuals were photo-identified, but only 318 of them were sized: 6 calves (≤ 10 meters), 33 immature (10-15 m), 261 adolescent-adult (> 15 m) and 18 olds (≥ 20 m). For the first time the site of the fin whale sub-population in the Pelagos Sanctuary was obtained by photo-identification and mark-recapture techniques. These techniques were used to estimate the site of the sub-population composed by individuals > 15 meters as 539 fin whales (95% confidence interval = 345-732) over the period 1990-1999. The number of calves was likely underestimated, as the sighting period (late spring-summer) was shifted with respect to the peak of births (late autumn). To fill this gap of knowledge we propose a simple mathematical model for the yearly dynamics of calves. After correcting the number of calves, a static life history table for the period 1990-2007 was set out. Our results highlight the highest survival proportions between calf and immature (61.1%) and the minimum between adolescent-adult and old (2.5%) vital stages. The overall life expectancy is estimated to be 6.3 years while the life expectancy of individuals entering the adolescent-adult stage is 14.3 years. This paper aims at providing a contribution for improving the conservation efforts and the demographic knowledge on fin whales in the Pelagos Sanctuary.

Redistribution of H3K27me3 and acetylated histone H4 upon exposure to azacitidine and decitabine results in de-repression of the AML1/ETO target gene IL3.

Human acute myeloid leukemia is characterized by a block in maturation caused by genetic and epigenetic alterations. We studied the effects of low concentrations of the DNA methyltransferase (DNMT) inhibitors 5-azacitidine and decitabine on apoptosis and on chromatin remodeling in an AML1/ETO inducible model of human AML. While both DNMT inhibitors induced apoptosis, only azacitidine did so via caspase activation, possibly through its exclusive non-DNA depending effects. We evaluated histone marks for permissive chromatin, H3K4me3, and acetylated histone H4, and for non-permissive chromatin, H3K9me2, and H3K27me3, at the promoter of the IL3 gene, which is under the direct control of AML1/ETO and is critical for myeloid maturation. We observed that low concentrations of DNMT inhibitors induced a loss of H3K27me3 and gain of acetylated histone H4 at the IL3 promoter exclusively in AML1/ETO-positive cells, which was associated with transcriptional reactivation of the IL3 gene.

Is lower limb venous drainage during peripheral extracorporeal membrane oxygenation necessary?

Extracorporeal membrane oxygenation (ECMO) is becoming a gold standard in acute heart failure, not responsive to inotrops and intra-aortic balloon contrapulsation. This diffusion is due to the possibility to implant it through peripheral cannulation and to perform long-time assistance. Nevertheless, this technique implies some problems concerning inferior limb perfusion. It is widely accepted that arterial distal cannulation and perfusion of the limb is mandatory, especially for long periods of assistance; but the necessity to implant a distal venous drainage is still discussed. We would like to present our experience on peripheral ECMO where we could avoid venous distal drainage uneventfully.

Postinfarction septal dissection and rupture evolved as an inferobasal pseudoaneurysm: a specific anatomical pattern.

In rare cases of posterior myocardial infarction, septal rupture is the consequence of a dissecting interventricular hematoma that evolves as a fibrotic septal chamber with two separate communications, towards left and right ventricle. This unusual anatomical pattern is generally unsuspected and described as a normal interventricular defect associated with a basal left ventricular aneurysm or pseudoaneurysm. We present a case where echocardiography and ventricular angiography did not detect this situation. As surgical implications are important, this peculiar anatomical pattern should be suspected especially in patients with asymptomatic postinfarction posterior septal rupture or in those with minimal clinical impairment.

Repair of posterior left ventricular aneurysm through transatrial approach.

Repair of posterior left ventricular ischemic aneurysms implies an extracardiac approach to reshape the ventricular geometry frequently associated with mitral surgery. A transatrial technique was described for lesions following mitral surgery or for subvalvular idiopathic cases. A transmitral approach was used for ischemic or traumatic pseudoaneurysm. We describe a case of postinfarction posterior true aneurysm with associated mitral incompetence. Both lesions were treated through an intracardiac approach. The posterior mitral leaflet was detached posteriorly to close the aneurysm with a patch, and the valve replaced sparing all subvalvular apparatus. This technique seems to be safe and allows to treat both lesions avoiding ventriculotomy.

Combined effects of 5-fluorouracil, folinic acid and oxaliplatin on the expression of carcinoembryonic antigen in human colon cancer cells: pharmacological basis to develop an active antitumor immunochemotherapy.

BACKGROUND: Five-fluorouracil (FU), mainly associated with leucovorin (L), plays an essential role in chemotherapy of colorectal carcinoma. Moreover, FU +/- L has been found to increase the expression of tumor-associated carcinoembryonic antigen (CEA), that may be an important target in therapeutic protocols of active specific immunotherapy. FU + L (FUL) are frequently combined with oxaliplatin (OXA) in advanced colon cancer patients. Thus, we investigated whether FUL in combination with OXA according to 2 different schedules may influence CEA expression in human colon cancer cells in vitro. METHODS: CEA protein expression was evaluated by cytofluorimetric and western blot analysis. Relative quantification of CEA mRNA was assessed by real time RT-PCR analysis. RESULTS: Levels of CEA protein and transcript were found to be higher in FUL-treated cells than in controls. However, when target cells were exposed to OXA before but not after FUL treatment, the up-regulation of CEA was partially inhibited. CONCLUSION: These results suggest that target cells must be exposed to OXA after but not before treatment with the fluoropyrimidine in order to exploit drug-induced up-regulation of CEA. This finding appears to provide useful information to design chemo-immunotherapy protocols based on FUL + OXA, combined with host's immunity against CEA directed cancer vaccines.