New fluorinated montmorillonites for the preparation of UV-cured coatings.

Montmorillonite was modified by means of a cation exchange reaction with two fluorinated ammonium salts, containing either a fluoroalkylic or a perfluoropolyether chain. The introduction of the fluorinated ammonium salts into the clay mineral galleries led in both cases to an increase of the interlayer distance, as revealed from the XRD spectra. However, the surfactant conformation achieved was different: a double layer structure was formed by the fluoroalkylic modifier, a paraffinic structure was present when the perfluoropolyether surfactant was used. This led to different results when the organoclays were dispersed into a typical UV curable dimethacrylate: a good degree of intercalation was achieved only with the clay modified by the fluoroalkylic surfactant.

Adenoviral gene transfer of Akt enhances myocardial contractility and intracellular calcium handling.

The serine-threonine kinase Akt/PKB mediates stimuli from different classes of cardiomyocyte receptors, including the growth hormone/insulin like growth factor and the beta-adrenergic receptors. Whereas the growth-promoting and antiapoptotic properties of Akt activation are well established, little is known about the effects of Akt on myocardial contractility, intracellular calcium (Ca(2+)) handling, oxygen consumption, and beta-adrenergic pathway. To this aim, Sprague-Dawley rats were subjected to a wild-type Akt in vivo adenoviral gene transfer using a catheter-based technique combined with aortopulmonary crossclamping. Left ventricular (LV) contractility and intracellular Ca(2+) handling were evaluated in an isolated isovolumic buffer-perfused, aequorin-loaded whole heart preparations 10 days after the surgery. The Ca(2+)-force relationship was obtained under steady-state conditions in tetanized muscles. No significant hypertrophy was detected in adenovirus with wild-type Akt (Ad.Akt) versus controls rats (LV-to-body weight ratio 2.6+/-0.2 versus 2.7+/-0.1 mg/g, controls versus Ad.Akt, P, NS). LV contractility, measured as developed pressure, increased by 41% in Ad.Akt. This was accounted for by both more systolic Ca(2+) available to the contractile machinery (+19% versus controls) and by enhanced myofilament Ca(2+) responsiveness, documented by an increased maximal Ca(2+)-activated pressure (+19% versus controls) and a shift to the left of the Ca(2+)-force relationship. Such increased contractility was paralleled by a slight increase of myocardial oxygen consumption (14%), while titrated dose of dobutamine providing similar inotropic effect augmented oxygen consumption by 39% (P<0.01). Phospholamban, calsequestrin, and ryanodine receptor LV mRNA and protein content were not different among the study groups, while sarcoplasmic reticulum Ca(2+) ATPase protein levels were significantly increased in Ad.Akt rats. beta-Adrenergic receptor density, affinity, kinase-1 levels, and adenylyl cyclase activity were similar in the three animal groups. In conclusion, our results support an important role for Akt/PKB in the regulation of myocardial contractility and mechanoenergetics.

[Telemedicine in neonatal emergencies]. / Consultazioni telematiche per emergenze neonatali.

UNLABELLED: Telemedicine is the transmission of medical notices and images among remote sites, that uses adequate audio-video systems. OBJECTIVE: To increase the quality and the amount of medical informations, avoiding unnecessary carriages. Among main fields of interest in Telemedicine, monitoring of cardiovascular parameters and medical emergency represent situations that need to be promptly and appropriately approached. In such a similar conditions, a preliminary transmission to III level Health Institutions of informations as Electrocardiograms or even Echocardiograms may play an essential role in the diagnosis, prognosis and treatment of emergent cardiovascular disease. METHODS: Since March 1998, an Audio-Video PC-based system that uses integrated services digital network (ISDN) at a bandwith of 384 Kbps, was installed at Pediatric Cardiac Surgery Department of Giovanni XXIII Hospital, Bari, Italy. On July 1999, thanks to Research Funds of the Health Ministry of Italy, similar audio-video systems that use ISDN were installed in the main pediatric institutions of provinces of Puglia and linked in a wide area network. RESULTS: We report the experience of Telemedicine of a Department of Pediatric Cardiology and Cardiac Surgery, and we try to analyze its impact on improvement of quality of care, once employed in provincial field.