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Notes: Background: Peripheral pulmonary artery stenosis is a relatively frequent anomaly responsible for right ventricular hypertension, significantly affecting the quality of life and the long-term prognosis of patients with congenital heart disease. Balloon angioplasty has been used to relieve pulmonary artery stenosis, but immediate and long-term results have not been completely satisfactory. Conversely, stent implantation seems a promising and more effective technique for the treatment of this vascular anomaly. Methods: Between April 1987 and September 1997, indication for interventional cardiac catheterization has been estabilished for 150 patients. Balloon angioplasty was performed in 120 patients (162 procedures) and stent implantation in 60 patients (79 stents). In 30 patients, both procedures have been carried out. Indication was based on the presence of right ventricular hypertension (right ventricular/systemic peak systolic pressure ratio ≥ 0.5), right ventricular dysfunction, or a markedly unbalanced pulmonary blood flow, especially after bidirectional cavopulmonary anastomosis. Criteria for technical success of balloon dilation were defined as a ≥ 50% increase in the predilation diameter, a ≥ 50% decrease in the transstenotic pressure gradient, or a ≥ 20% decrease in the right ventricular-to-aortic pressure ratio. Mean balloon/stenosis diameter ratio was 3.0 ± 0.7 (range 1.8–4.2). Time between primary surgery/balloon angioplasty and stent implantation was 18 ± 7 months (range 8–21 months). Stainless steel balloon-expandable endovascular stents were maximally dilated to 12–18 mm of diameter, and high-pressure dilations were performed to further expand the stent, if necessary. Results: After balloon angioplasty, the diameter of the stenotic segment increased from 3.1 ± 0.3 to 5.1 ± 1.4 mm (P 〈 0.01), the gradient across the stenotic segment dropped from 51 ± 19 to 28 ± 8 mmHg (P 〈 0.01), and the right ventricular/systemic peak pressure ratio decreased from 0.81 ± 0.20 to 0.65 ± 0.15 (P 〈 0.05). No significant difference between procedures with low-pressure and high-pressure dilation was recorded. Success rates using the above-mentioned criteria could be assessed as high as 60%. After stent implantation, the diameter of the stenotic segments increased from 3.5 ± 1.2 to 13.2 ± 3.4 mm (P 〈 0.01), the pressure gradient across the stenotic segment dropped from 53 ± 30 to 13 ± 10 mmHg (P 〈 0.01), and the mean right ventricular/systemic pressure ratio decreased from 0.84 ± 0.2 to 0.40 ± 0.15 (P 〈 0.01). Immediate overall success for balloon angioplasty was achieved in 73 of 120 patients compared with 58 of 60 patients submitted to stent implantation (60% vs 97%, P 〈 0.001). The complication rate was 6.9% (5/162 procedures) in the balloon angioplasty group and 1.2% (1/79 implants) in the stent group. Restenosis has been recorded in 25% of the balloon group patients, in respect to 2% of the stent group. Conclusions: Peripheral pulmonary stenosis (PPS) is an important factor conditioning outcome of patients with congenital heart defects. Balloon angioplasty may be technically effective, but it often fails if clinical criteria and impact on patient's outcome are considered. In our experience, the use of high-pressure balloons did not change the success rate of balloon dilation. Stent implantation seems to offer a better and more definitive approach for the relief of PPS.

Notes: Abstract Our previous ultrastructural and immunohistochemical studies, in vivo and in vitro, have shown important modifications of the basement membrane of psoriatic skin, which could play a key role in the alterations of keratinocyte adhesion, migration, proliferation and differentiation. In order to complete the morphological examination of all the structures in the dermoepidermal junction of psoriatic skin, we carried out a scanning electron microscopic study using biopsies taken from eight psoriatic patients. The biopsies were fixed in a mixture of 0.2% paraformaldehyde and 0.25% glutaraldehyde in 0.1 M cacodylate buffer at pH 7.4. The specimens were then frozen in liquid nitrogen and fractured following the natural cleavage planes and observed under a Jeol JSM-6301F field emission scanning electron microscope operating at 1.8–2.0 kV. The basal keratinocytes observed showed pore-like depressions on the lateral plasmalemma and villous-like projections in very dilated intercellular spaces. Moreover the basal cell plasma membrane was seen to rest on the papillary dermis without interposition of the lamina densa. The detachment of some keratinocytes enabled the examination of the lamina densa, which appeared slightly granular with numerous focal interruptions through which it was possible to observe the underlying collagen fibres. These findings, together with previously reported findings, support the hypothesis that in psoriasis molecular and structural alterations of the dermoepidermal junction are present, that could fundamentally alter the regulation of the cytomorphological processes and the normal functions of the basement membrane.

Notes: Abstract • Background: These is no consensus in the literature regarding the differentiation of conjunctival goblet cells in vertebrates. • Method: The conjunctival epithelium of the chick was studied before and after hatching in order to demonstrate the morphological evolution of the goblet cells. The entire conjunctiva was processed for light microscopy either on semithin sections stained with toluidine blue-pironine or on traditional sections stained with Alcian blue pH 2.5-PAS. • Results: It was possible to demonstrate that goblet cells underwent remarkable changes in their secretory activity. At 12 h after hatching, isolated Alcian blue-positive cells were present in the fornix. At 24 h after hatching, cells positive for both Alcian blue and PAS were scattered among epithelial cells. Two days after hatching, cells which reacted positively only to PAS were also present. • Conclusion: It is suggested that the differentiation of conjunctival goblet cells occurs first in the fornix, probably due to the particular vascular environment of this region, and then spreads all over the conjunctiva.

Notes: Abstract In liver mitochondria isolated from hypothyroid rats, the rate of ATP synthesis is lower than in mitochondria from normal rats. Oligomycin-sensitive ATP hydrolase activity and passive proton permeability were significantly lower in submitochondrial particles from hypothyroid rats compared to those isolated from normal rats. In mitochondria from hypothyroid rats, the changes in catalytic activities of F0F1-ATP synthase are accompanied by a decrease in the amount of immunodetected β-F1, F01-PVP, and OSCP subunits of the complex. Northern blot hybridization shows a decrease in the relative cytosolic content of mRNA for β-F1 subunit in liver of hypothyroid rats. Administration of 3,5,3′-triodo-L-thyronine to the hypothyroid rats tends to remedy the functional and structural defects of F0F1-ATP synthase observed in the hypothyroid rats. The results obtained indicate that hypothyroidism leads to a decreased expression of F0F1-ATP synthase complex in liver mitochondria and this contributes to the decrease of the efficiency of oxidative phosphorylation.

Notes: Abstract The evaluability and reliability of proliferative activity (expressed as3H-thymidine labeling index,3H-TdR LI) and ploidy determinations on core needle biopsies were compared with those obtained on surgical material from the same breast cancers. The evaluability of3H-TdR LI on core needle biopsies was markedly lower than that on surgical material (53% vs 100%), and the association between3H-TdR LI values in the 16 cases with both evaluable determinations was poor (rs=0.45). Conversely, determinations of ploidy on core needle biopsy and surgical material provided superimposable results, in terms of evaluability (91% vs 100%) and reliability (rs=0.99). Further efforts are needed to improve sampling procedures for a reliable assessment of biological markers.