Concurrent subarachnoid haemorrhage and internal carotid artery dissection: a transcranial colour-coded sonography diagnosis

We report the case of a young woman affected by an aneurysmal subarachnoid haemorrhage (SAH) and numerous anatomic abnormalities. A Transcranial Colour-Coded Duplex Sonography, performed with the aim of monitoring the vasospasm, showed a non-pulsatile flow with loss of sharp systolic peak and lowering of mean flow velocities in the right extracranial Internal Carotid Artery (ICA) and all its intra-cranial branches. This event suggested a possible concomitant acute right ICA sub-occlusion with a lack of collateral circulation. This type of flow is typically found in systemic and brain arteries of patients undergoing to venous-arterial extracorporeal membrane oxygenation or to left ventricular assist devices. The absence of an adequate cerebral collateral circulation might be the explanation for this type of atypical flow. Aneurysms and arterial dissections contribute to SAH and ischemic stroke events, leading to long-term physical and cognitive disability. In our case, the prompt neurosonological diagnosis leaded to patient's good outcome.

Design of a custom-made device for real-time optical measurement of differential mineral concentrations in three-dimensional scaffolds for bone tissue engineering

Monitoring bone tissue engineered (TEed) constructs during their maturation is important to ensure the quality of applied protocols. Several destructive, mainly histochemical, methods are conventionally used to this aim, requiring the sacrifice of the investigated samples. This implies (i) to plan several scaffold replicates, (ii) expensive and time consuming procedures and (iii) to infer the maturity level of a given tissue construct from a cognate replica. To solve these issues, non-destructive techniques such as light spectroscopy-based methods have been reported to be useful. Here, a miniaturized and inexpensive custom-made spectrometer device is proposed to enable the non-destructive analysis of hydrogel scaffolds. Testing involved samples with a differential amount of calcium salt. When compared to a reference standard device, this custom-made spectrometer demonstrates the ability to perform measurements without requiring elaborate sample preparation and/or a complex instrumentation. This preliminary study shows the feasibility of light spectroscopy-based methods as useful for the non-destructive analysis of TEed constructs. Based on these results, this custom-made spectrometer device appears as a useful option to perform real-time/in-line analysis. Finally, this device can be considered as a component that can be easily integrated on board of recently prototyped bioreactor systems, for the monitoring of TEed constructs during their conditioning.

Temporal modes of hub synchronization at rest

The brain is a dynamic system that generates a broad repertoire of perceptual, motor, and cognitive states by the integration and segregation of different functional domains represented in large-scale brain networks. However, the fundamental mechanisms underlying brain network integration remain elusive. Here, for the first time to our knowledge, we found that in the resting state the brain visits few synchronization modes defined as clusters of temporally aligned functional hubs. These modes alternate over time and their probability of switching leads to specific temporal loops among them. Notably, although each mode involves a small set of nodes, the brain integration seems highly vulnerable to a simulated attack on this temporal synchronization mechanism. In line with the hypothesis that the resting state represents a prior sculpted by the task activity, the observed synchronization modes might be interpreted as a temporal brain template needed to respond to task/environmental demands .

Study of the Hemocoagulative Parameters in Hemoperfusion on Polymer Coated Resins

A hemoperfusion column containing anionic exchange resin coated with a new polymer has been tested in vivo for blood compatibility.

The hemocoagulative parameters, evaluated before and after the cartridge during hemoperfusion, did not show any significant alteration even as regards the number and the functionality of the platelets nor as regards a possible activation of the fibrinolysis process.

On the basis of these results, the hemoperfusion system examined can be regarded as hemocompatible from the hemocoagulative standpoint.

[Evaluation of the biocompatibility of grafts for bone defects]

BACKGROUND

This paper examines a new material composed of polylactic and polyglycolic acids mixed with destrane easy to handle in bone defect reconstruction in periodontology and implantology: its name is fisiograft.

METHODS

According to the European directives, fisiograft was checked for some biological tests selected for its specific use. In particular, tests of cytotoxicity, genotoxicity, sensitization and implantation in rabbit's femurs were carried out.

RESULTS

The results show that the composite material is not cytotoxic when it is in direct and indirect contact with murine fibroblasts. It is not genotoxic and not allergenic. The implantation in rabbit, already after 30 days, shows that around the material there is a rapid bone growth and the material is reabsorbing. The degradation is suitable for its clinical use.

CONCLUSIONS

Fisiograft showed to be biocompatible, easy to handle and its degradation kinetics in bone is appropriate.

Study of the hemocoagulative parameters in hemoperfusion on polymer coated resins

A hemoperfusion column containing anionic exchange resin coated with a new polymer has been tested in vivo for blood compatibility. The hemocoagulative parameters, evaluated before and after the cartridge during hemoperfusion, did not show any significant alteration even as regards the number and the functionality of the platelets nor as regards a possible activation of the fibrinolysis process. On the basis of these results, the hemoperfusion system examined can be regarded as hemocompatible from the hemocoagulative standpoint.