Follow-up of atheroma burden with sequential whole body contrast enhanced MR angiography:a feasibility study

Assess the feasibility of whole body magnetic resonance angiography (WB-MRA) for monitoring global atheroma burden in a population with peripheral arterial disease (PAD). 50 consecutive patients with symptomatic PAD referred for clinically indicated MRA were recruited. Whole body MRA (WB-MRA) was performed at baseline, 6 months and 3 years. The vasculature was split into 31 anatomical arterial segments. Each segment was scored according to degree of luminal narrowing: 0 = normal, 1 = <50 %, 2 = 50–70 %, 3 = 71–99 %, 4 = vessel occlusion. The score from all assessable segments was summed, and then normalised to the number of assessable vessels. This normalised score was divided by four (the maximum vessel score) and multiplied by 100 to give a final standardised atheroma score (SAS) with a score of 0–100. Progression was assessed with repeat measure ANOVA. 36 patients were scanned at 0 and 6 months, with 26 patients scanned at the 3 years follow up. Only those who completed all three visits were included in the final analysis. Baseline atherosclerotic burden was high with a mean SAS of 15.7 ± 10.3. No significant progression was present at 6 months (mean SAS 16.4 ± 10.5, p = 0.67), however there was significant disease progression at 3 years (mean SAS 17.7 ± 11.5, p = 0.01). Those with atheroma progression at follow-up were less likely to be on statin therapy (79 vs 100 %, p = 0.04), and had significantly higher baseline SAS (17.6 ± 11.2 vs 10.7 ± 5.1, p = 0.043). Follow up of atheroma burden is possible with WB-MRA, which can successfully quantify and monitor atherosclerosis progression at 3 years follow-up

Expression of Constitutively Active CDK1 Stabilizes APC-Cdh1 Substrates and Potentiates Premature Spindle Assembly and Checkpoint Function in G1 Cells

Mitotic progression in eukaryotic cells depends upon the activation of cyclin-dependent kinase 1 (CDK1), followed by its inactivation through the anaphase-promoting complex (APC)/cyclosome-mediated degradation of M-phase cyclins. Previous work revealed that expression of a constitutively active CDK1 (CDK1AF) in HeLa cells permitted their division, but yielded G1 daughter cells that underwent premature S-phase and early mitotic events. While CDK1AF was found to impede the sustained activity of APC-Cdh1, it was unknown if this defect improperly stabilized mitotic substrates and contributed to the occurrence of these premature M phases. Here, we show that CDK1AF expression in HeLa cells improperly stabilized APC-Cdh1 substrates in G1-phase daughter cells, including mitotic kinases and the APC adaptor, Cdc20. Division of CDK1AF-expressing cells produced G1 daughters with an accelerated S-phase onset, interrupted by the formation of premature bipolar spindles capable of spindle assembly checkpoint function. Further characterization of these phenotypes induced by CDK1AF expression revealed that this early spindle formation depended upon premature CDK1 and Aurora B activities, and their inhibition induced rapid spindle disassembly. Following its normal M-phase degradation, we found that the absence of Wee1 in these prematurely cycling daughter cells permitted the endogenous CDK1 to contribute to these premature mitotic events, since expression of a non-degradable Wee1 reduced the number of cells that exhibited premature cyclin B1oscillations. Lastly, we discovered that Cdh1-ablated cells could not be forced into a premature M phase, despite cyclin B1 overexpression and proteasome inhibition. Together, these results demonstrate that expression of constitutively active CDK1AF hampers the destruction of critical APC-Cdh1 targets, and that this type of condition could prevent newly divided cells from properly maintaining a prolonged interphase state. We propose that this more subtle type of defect in activity of the APC-driven negative-feedback loop may have implications for triggering genome instability and tumorigenesis

The T/J boundary in shallow marine environments: the example of Mount Messapion section (Chalkida, Greece). Rivista Italiana di Paleontologia e Stratigrafia.

In the Mount Messapion area (Chalkida, Greece) a continuous and expanded section of Triassic/Jurassic (T/J) limestone outcrops. This section consists of a pile, 710 m thick, of the classic shallowing-upward peritidal cycles; the persistence of the facies and the lack of paleoenvironmental changes across the T/J boundary allowed studying the distribution of shallow water microfossils. The T/J boundary was placed in the upper part of the section in correspondence with (i) the last occurrence of Triasina hantkeni, (ii) the abrupt disappearance of megalodontid faunas and (iii) the presence of Lower Jurassic microfossil assemblages. This paleontological reorganization happens suddenly, it is not controlled by any facies change, and surprisingly, it seems to produce no evident modification in the vertical stacking pattern of the cycles. A detailed facies analysis, performed along a stratigraphic interval about 290 m thick (60 metres above the T/J boundary and 230 below), allowed the recognition of peritidal cycles: five different elementary cyclothemes are described and their distribution along the section is given. This integrated stratigraphic study represents an attempt to highlight the relationship between the changes of carbonate producers and sea level variations across the T/J boundary

What’s happen at the T/J boundary in shallow marine environments – The example of Mount Messapion Section (Chalkis, Greece)

This work starts from an integrated stratigraphic study performed on a continuous and expanded section of Triassic-Jurassic (T/J) limestones outcropping at Mt. Messapion. The section consists of a pile, 710 metres thick, of the classic shallowing-upward, peritidal cycles and their age is constrained to Late Triassic - Early Jurassic by micro and macro fossils as foraminifers, green algae and bivalves.The multidisciplinary investigations on this section allow to obtain a new integrated stratigraphic data helpful for the identification of the Late Triassic-Early Jurassic events in shallow water successions

Periapical cemento-osseous dysplasia: clinicopathological features.

periapical cemento-osseus dysplasia is a rare benign lesion. case repor