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L Pannarale

Publications and source records attributed to L Pannarale.

27 records · Page 2Linked to original sources
PubMed1988

Microcorrosion casting in normal and pathological biliary tree morphology.

The organization of the intrahepatic biliary tree was studied in three dimensions by scanning electron microscopic (SEM) corrosion casts, in normal and cholestatic rat liver. In the normal liver the observation revealed the features of the biliary passages from the bile canaliculi to the canaliculo-ductular junction, to the ductules and the bile ducts, confirming previous SEM observations. In cholestatic liver, the modifications and the proliferation of bile ductules appear clearly. Resin flow from canalicular to sinusoidal network was never observed. The method was found to be very useful in the evaluation of the architecture of the intrahepatic biliary tree, under normal as well as under pathological conditions.

Animals↗
PubMed1986

Microcorrosion casts in the microcirculation of skeletal muscle.

The authors review the contribution of microcorrosion cast studies towards clarifying the structure of skeletal muscle microcirculation. Former studies performed on naturally contracted muscles show the presence of a primary and a secondary arterial network and a capillary network. At the level of the capillary network pericyte imprints are present. Muscles characterized by different types of metabolism show different features of the capillary pattern. Other authors have affirmed that the extended muscle is characterized by long and straight capillaries, while the contracted one features clusters of vessels all around a muscle fiber. The authors have made the present observations in order to determine how the capillary pattern of muscles with different metabolism is modified by extension and shortening of the muscle belly. The capillary pattern observed appears very similar to that observed in former studies. The differences between the oxidative and the glycolytic muscle are evident in every condition of the muscle belly. These data confirm the theory that there is a permanent endogenous difference in microcirculation between oxidative and glycolytic muscle, determined by muscle fiber metabolism.

Animals↗
PubMed1985

An S.E.M. corrosion cast study on pericyte localization and role in microcirculation of skeletal muscle.

The authors used the microcorrosion cast technique to study the localization and the role of pericytes in the microcirculation of skeletal muscle. Both fast twitch muscles, the tibialis anterior and the pectineus muscles, and a slow twitch one, the soleus muscle, were studied, because of morphological differences of their capillary networks. The observation of peculiar imprints on the surface of vascular casts, strategically sited in the microvascular bed, were related to the presence of pericytes apposed to the endothelial lining. The role of pericytes in equalizing the local blood flow to metabolic needs and in maintaining capillary blood flow despite pinching of vessels is discussed.

Animals↗
PubMedDate not supplied

Topical ibopamine and corticosteroids in the treatment of post-surgery ocular hypotony.

PURPOSE: The aim of the present preliminary study, performed on post-surgical hypotony, was the evaluation of the effects on ocular hypotony of the concomitant administration of ibopamine and corticosteroids. METHODS: 14 patients (11 males-3 females; mean age 47 years) with ocular hypotony following several vitroretinal surgical intervention in different districts, were enrolled. The inclusion criteria were: mean IOP during tonometric curve equal or lower than 6 mmHg, stable IOP for at least 60 days, ongoing treatment with 0.1% dexamethasone (4 times/day), successful surgical intervention, 2% ibopamine (4 times/day) was added to the corticosteroid therapy for 30-60 days. RESULTS: Before ibopamine administration, mean IOP was 4.07 mmHg SD 1.71. At the end of the treatment period, mean IOP increased by 89% in comparison to baseline values (+ 3.64 mmHg SD 5.57). This difference was statistically significant (paired t = 2.39; P = 0.03). One month after ibopamine-treatment discontinuation, mean IOP decreased to pre-treatment values (4.86 mmHg SD 3.50). CONCLUSIONS: The results of the present study, although preliminary, suggest the possibility of a future pharmacological treatment of ocular hypotony with ibopamine, whose rationale is based on the increase of aqueous humor production by stimulating the D1 dopaminergic receptor.

Administration, Topical↗
PubMedDate not supplied

Ibopamine in glaucoma diagnostics: a new pharmacological provocative test.

PURPOSE: Ibopamine is used when performing provocative tests, thanks to its pharmacological property of increasing ocular pressure in eyes with outflow system impairment. This study summarizes the latest results that we have achieved with reference to its clinical-diagnostic use. METHODS: 175 (250 eyes) POAG patients, 101 (190 eyes) glaucoma suspects with mild ocular hypertension, 39 (64 eyes) NTG patients and 163 (326 eyes) healthy volunteers underwent an ibopamine provocative test. Among the POAG and the glaucoma suspects, 49 (92 eyes) and 20 (38 eyes) patients were selected who, starting from the performing of ibopamine test, had at least one year of perimetric follow-up. These patients have been assessed for the perimetric defect progression in relation to the (negative or positive) response to ibopamine. RESULTS: the ibopamine test was positive for 92% of the glaucomatous patients, 61% of the glaucoma suspects, 52% of the NTG patients and 0% of the healthy volunteers. It was observed that 28% of the ibopamine-positive glaucoma suspects showed a perimetric deterioration during an average 2.5-year follow-up. No perimetric deterioration was found on ibopamine-negative glaucoma suspects (Fisher's exact test: p = 0.038). Among glaucomatous patients, 46% of the test-positive individuals showed a progressive trend of the perimetric defect, as against about 8% of glaucomatous test-negative patients (Fisher's exact test: p = 0.003). CONCLUSIONS: We believe that the ibopamine provocative test can be usefully applied especially to epidemiological screening studies to identify patients who might develop ocular hypertension or glaucoma and in the follow-up of glaucoma suspects, to identify individuals who have a greater risk of developing perimetric defects.

Administration, Topical↗
PubMedDate not supplied

Retinal microcirculation as revealed by SEM corrosion casts in the rat.

The morphology of the retinal microcirculation has been extensively studied by different techniques. Nevertheless, some problems concerning the capillary bed lamination and pre- and postcapillary patterns have not yet been clarified. In the present study the SEM corrosion cast technique was employed to study the three-dimensional relationships of rat retinal vessels and to follow the smallest vascular branches. Rat retina is considered a useful experimental model for a number of pathologies which affect the microvascular bed deeply. Two precapillary patterns have been observed. Precapillary arterioles gave rise to capillaries both as terminal branches or as collaterals. The former pattern of ramification allows only a regulation of flow in a whole group of capillaries downstream, the latter pattern could provide a finer regulation of blood flow. SEM corrosion casts have shown very well the lamination of the capillary bed: one can easily realize this by seeing the overlapped meshes of the two different planes, vessels in between the two capillary laminae can always be followed from one meshwork to the other. This three-dimensional organization is an interesting model for retinal circulation because it shows many features in common with the retina of humans and primates.

Animals↗
PubMedDate not supplied

A morphological study on femoral heads in human hip joint osteoarthrosis.

Several pathogenetical and clinical interpretation of osteoarthritic modifications are given in the literature. In this work we tried to compare in humans macroscopic, structural and ultrastructural observations on eight osteoarthritic with four femural heads from control patients. The sample for Light Microscopy and Scanning Electron Microscopy observations came from selected regions of the femural head, which included both cartilage and bone tissue of loaded and unloaded regions. The cartilage showed superficial lesions, such as erosions and fissures, and deep lesions that included matrix alterations and chondrocyte proliferation. In relation to the thickening of the subchondral bone we noticed an irregular bone-cartilage surface with signs of bone tissue proliferation. The trabeculae appeared thickened in loaded zones and rarefied in unloaded ones. Cavities were sometimes present at different depths in cancellous bone. Our observations allow us to conclude that cartilage lesions are precocious, diffusely located and relatively independent of the considered zone of the femural head, while bone tissue alterations seem evenly sited and chronologically subsequent. The cavities in the cancellous bone could produce load modifications and consequent bone deformity.

Aged↗