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D Lepore

Publications and source records attributed to D Lepore.

11 recordsLinked to original sources
PubMed2003

Efficacy and safety of continuous intravenous infusion of remifentanil in preterm infants undergoing laser therapy in retinopathy of prematurity: clinical experience.

BACKGROUND: Preterm infants often require surgery. As experimental evidence suggests that premature infants may experience pain and this could even result in fatal complications, the anaesthesiologist must face problems related to lowbirth weight, high risk of hypothermia, concomitant pulmonary disease and metabolic and receptor immaturity. Recently remifentanil has been considered an optimal analgesic drug in a preterm infant undergoing mechanical ventilation and frequent surgical manoeuvres, but no clinical studies have been reported in the literature. The aim of our study was to evaluate the efficacy of a continuous intravenous infusion of remifentanil in premature infants undergoing laser therapy for retinopathy of prematurity (ROP). METHODS: Six premature infants with ROP were scheduled for laser therapy. The procedure was performed in the neonatal intensive care unit. Transcutaneous carbon dioxide, pulse oximetry, respiratory rate, ECG and noninvasive blood pressure were continuously monitored. Infusion of remifentanil started with a dose of 0.75-1 microg x kg-1x min-1, 1 h before surgery. A midazolam bolus dose (0.20 mg x kg-1) was administered and the remifentanil infusion was increased to 3-5 microg x kg-1x min-1 taking into account haemodynamic and respiratory changes or spontaneous movements. RESULTS: Increased dosage was necessary only for 10 min during the procedure. No changes in temperature and ventilatory settings were observed and after 2 h from the surgical procedure the preterm infants were back to their preoperative status. CONCLUSIONS: A continuous infusion of remifentanil allowed optimal control of surgical stress and a return to preoperative status and ventilatory settings without side-effects.

Anesthetics, Intravenous↗
PubMed2002

Chronic taurine supplementation ameliorates oxidative stress and Na+ K+ ATPase impairment in the retina of diabetic rats.

This study evaluates the effect of 4 months supplementation with 2% and 5% taurine (w/w) on the retina of diabetic rats. In non-diabetic rats, taurine does not modify glycemia, body weight, retinal conjugated dienes (CD), lipid hydroperoxide (LP), and Na(+)K(+)ATPase activity. In diabetic rat, at 2, 4, 8, 16 weeks following the onset of diabetes, retinal CD and LP are significantly and progressively increased, while pump activity is gradually and significantly reduced. In taurine supplemented diabetic rats, glycemia is not affected but lipid peroxidation is significantly decreased. Finally, taurine preserves ATPase activity being 5% more effective than 2% taurine. We conclude that taurine supplementation ameliorates biochemical retinal abnormalities caused by diabetes, thereby suggesting that taurine may have a role in the prevention of retinal changes in diabetes.

Animals↗
PubMed1991

[Ocular anomalies in Alagille's syndrome].

The authors examine a family, in which two brothers were affected by a severe expression of arteriohepatic dysplasia (ADH, Alagille syndrome), an autosomal dominant disorder associated with intrahepatic cholestasis, characteristic facial appearance, congenital embryotoxon. One of these two cases presented a keratoconus and both had retinal pigmentary degeneration with pigment clumping. The father showed a benign expression of ADH, including the characteristic facial appearance and posterior embryotoxon. Another brother presented only retinal pigmentary abnormalities and a bilateral arcus senilis-like corneal opacity, without any other clinical sign of ADH. The presence of posterior embryotoxon in all the cases of Alagille syndrome confirms that this sign is a hallmark of ADH, also in its benign expression.

Abnormalities, Multiple↗
PubMed1989

Variations in the severity of retinopathy seen in newborn rats supplemented with oxygen under different conditions of hyperbarism.

The purposes of this experimental study were to evaluate the effects of oxygen supplementation delivered under hyperbaric conditions on the retinas of newborn rats and to determine the minimum and maximum levels of hyperbarism capable of protecting the retinal vessels from the toxic effects of oxygen without determining lethal effects in this experimental model. A control group of newborn rats were maintained with their mother for the first 12 days of life under room-air conditions. A second group of animals were exposed to a hyperbaric environment (+81 kPa) under normoxic conditions for the first 7 days of life and subsequently returned to normobaric conditions for the next 5 days. Examination of the retinal flat mounts from this latter group of animals revealed essentially normal vascular networks with only a modest degree of vasoconstriction. Two other litters of ratlings, with their mothers, were given supplemental oxygen at an FiO2 of 80% under a compression pressure of +101.25 kPa. In this group of animals, death of both of the mother rats from pulmonary edema occurred on the first day of treatment, and, in spite of immediate mother substitution, the newborn rats succumbed to the same complication. Five other groups, each containing two litters of newborn rats with their mothers, were exposed to FiO2s of 80% at hyperbaric levels ranging from +20.25- to +81.0 kPa for the first 7 days of life. On the eighth day, the FiO2s were reduced to 21%. After 5 days of room-air recovery, the animals were killed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Oxygen-induced retinopathy in newborn rats: orthograde axonal transport changes in optic pathways.

The aim of this study was to evaluate axonal transport along the optic pathways of neonatal rats in which oxygen-induced retinopathy had been experimentally produced. One group of 116 rats was exposed to an FiO2 of 80% for the first 5 days of life and then kept under room-air conditions for the following 10 days. A second group of 108 rats was maintained under room-air conditions for the first 15 days of life. On the 16th day of life, 1.5 microliter of [35S]taurine was injected into the vitreous of the right eye of each animal and radioactivity was measured, at various intervals from the injection, in the right optic nerve, the chiasma and the left optic tract. Statistically significant reductions in axonal transport were observed in all three segments of the optic pathways of the oxygen-supplemented animals compared with the control group. The authors discuss various explanations for their findings and hypothesize that the alterations observed in this study may have significant and more or less long-term effects on the normal maturation of the visual system.

Animals↗
PubMedDate not supplied

Oxygen-induced retinopathy in the newborn rat: a scoring system for the evaluation of retinal vascular changes. Scoring system for OIR in the rat.

The authors describe a scoring system they have developed for evaluating damage produced in the retinal vascular network of the newborn rat by exposure to oxygen. India ink-injected retinal flat mounts are used. The scoring system provides for division of the retina into three concentric zones with the optic disk as a center point. Each retinal quadrant is then examined for the presence of the following lesions of progressive severity: vaso-obliteration of the capillary network, loss of the periarteriolar capillary-free zone, newly formed capillary tufts. When more than one type of lesion is present in a quadrant, only the most severe lesion is considered. The numerical score corresponding to that lesion is then multiplied by the factor corresponding to the concentric zone in which the lesion lies to give the quadrant score. The total retinal score is represented by the sum of the four quadrant scores. This type of system, if adopted by other investigators, can facilitate precise and systematic description of the results of different experimental protocols.

Animals↗
PubMedDate not supplied

Effect of light on oxygen-induced retinopathy in the rat model. Light and OIR in the rat.

The purpose of this study was to establish whether exposure to intense lighting favors the development or aggravates experimental oxygen-induced retinopathy in the newborn rat. Five groups of Wistar rats were studied. The control group was maintained for the first 14 days of life under conditions of cyclical (12L:12D) lighting at 12 Lx in room air. Two other groups were subjected, for the same amount of time, to semi-darkness (2 Lx; 12L: 12D), one with room air and the other with supplemental 80% oxygen. The final two groups were exposed to the same room air and hyperoxic treatments under intense lighting conditions (600 Lx; 12L:12D). After the treatment period, four rats were randomly chosen from each group, sacrificed and their retinas examined under electron microscope. Marked structural changes were seen only in the photoreceptor outer segments of those rats exposed to intense light. In eighty-five of the remaining rats retinal vascular morphology was examined in retinal flat mounts after intracardiac injection of India ink. Retinopathy was observed in rats treated with hyperoxia but no significant differences could be attributed to the light conditions under which the retinopathic rats had been maintained. In the rest of the rats, axonal transport along the optical pathways was evaluated after intravitreal injection of (3H) taurine. In the two groups exposed to hyperoxia, axonal transport was altered, but less markedly in those exposed to intense lighting than in those exposed to semi-darkness. Intense illumination under conditions of normoxia favors axonal transport. Exposure to intense lighting does not seem to aggravate oxygen induced retinopathy in the rat though it does produce structural lesions of the photoreceptors.

Animals↗