Development and validation of low-intensity pulsed ultrasound systems for highly controlled in vitro cell stimulation

This work aims to describe the development and validation of two low-intensity pulsed ultrasound stimulation systems able to control the dose delivered to the biological target. Transducer characterization was performed in terms of pressure field shape and intensity, for a high-frequency range (500 kHz to 5 MHz) and for a low-frequency value (38 kHz). This allowed defining the distance, on the beam axis, at which biological samples should be placed during stimulation and to exactly know the intensity at the target. Carefully designed retaining systems were developed, for hosting biological samples. Sealing tests proved their impermeability to external contaminants. The assembly/de-assembly time of the systems resulted ~3 min. Time-domain acoustic simulations allowed to precisely estimate the ultrasound beam within the biological sample chamber, thus enabling the possibility to precisely control the pressure to be transmitted to the biological target, by modulating the transducer's input voltage. Biological in vitro tests were also carried out, demonstrating the sterility of the system and the absence of toxic and inflammatory effects on growing cells after multiple immersions in water, over seven days.

[Double cardiac fibroma in a newborn infant]

The authors describe the autopsy finding of two fibromas within the left ventricular wall of a five-day-old newborn. Histochemistry and immunohistochemistry showed the lesion as a purely fibroblastic proliferation, with intense elastic fibers formation and secondary morphological alteration and biological damage of the pre-existing muscular fibers. The authors, on the basis of the phases of the cardiac metamers development and of myocardial tissue differentiation, exclude any relationship with disembryogenetic factors, and hence the hamartomatous origin of the lesion, despite their onset in the first months of intrauterine growth.

[Ventricular hypoplasia in congenital heart diseases]

Twenty-seven cases of autopsy showing hypoplasia of one of the ventricular cavities, prevalently the left, were selected from a series of 103 congenital cardiopathies (1979-1990). In 9 cases ventricular hypoplasia formed part of complex malformative syndromes with a well-known physiognomy: a further 18 cases showed a complete (9 cases) or incomplete (9 cases) hypoplastic heart syndrome. Subjects were prevalently female and the presence of other malformations indicating a genetic dysfunction was less evident than in other cardiopathies. The different pathogenetic hypotheses are discussed in the light of macro- and microscopic morphological factors, of which the most plausible is that involving an anomalous position or orientation of the musculo-membranous folds which give rise to the septation system of the various metamers of the cardiac tube.

[Cardiac malformations with septal defects. Apropos of a case of biloculate heart with transposition and aortic atresia]

The Authors describe a case of uniatrial univentricular heart with a right transposition and atresia of the aorta. This case forms part of an autoptic series of 74 congenital cardiopathies with defects of the septal system: monometameric (52 cases), polymetameric (22 cases), and limited (66 cases) or broad DIA, DIV or FAP types (8 cases). Having outlined the correlations between the type of defect and the complex morphogenetic events, whose close integration leads to a continuous septal system, the Authors focus their attention on the common associations between septal defects and other cardio-vascular anomalies (66 cases). The analysis of findings supports hypothesis that many of these are due to alterations in the position and direction of individual septal buds are should be seen against the overall background of septal pathology. Under these circumstances the pathogenetic importance of alterations of the complex movements presented by the cardiac type during the course of septal development and, to an event greater extent, possible alterations of the embryonal hematic flow are underlined.

[Evaluation at midterm of the clinico-instrumental efficacy and tolerance of picotamide in patients with obliterative arteriopathy of the lower limbs]

After a 4-week wash-out period, picotamide was administered to 25 patients affected by chronic arteriopathy of the lower limbs (scale 2 according to Fontaine) at a dose of 900 mg/die for 90 days, and then at a dose of 600 mg/die for a further 90 days, in order to assess its efficacy according to the following parameters: duration of gait, residual pressure index (RPI) resting the ankles, hematochemicals, electrocardiogram. At the end of the study a statistically significant increase was observed in the duration of gait and RPI at the ankles and, of the hematochemical parameters, in an increase in fibrogenic degradation products. Adverse reactions were only observed in 3 patients and regressed spontaneously. In conclusion, picotamide was found to be efficacious in patients affected by chronic obliterating arteriopathy of the lower limbs with the possibility of reducing the dose after 3 months of therapy.

A study on the effects of some drugs on DOCA induced hypertension in the rat

Chronic treatment with various drugs reduced the increase in arterial blood pressure, the ventricular hypertrophy and the thickening of pulmonary arterial and arteriolar walls.