Biomedical subjects

G Calamandrei

Publications and source records attributed to G Calamandrei.

43 records · Page 3Linked to original sources

PubMedDate not supplied

Nerve growth factor plasma levels and ventricular repolarization in Rett syndrome.

Rett syndrome is a severe neurological developmental disorder. In this syndrome, the high incidence of sudden death is correlated with an alteration of ventricular repolarization. The purpose of this study was to evaluate plasmatic levels of nerve growth factor (NGF) in Rett patients with prolonged corrected QT (QTc) interval in comparison with those of Rett patients with normal QTc. We observed 23 female Rett patients (9.9+/-4.7 years). NGF plasma levels and QTc interval were measured in all patients. Student t-test was performed for statistical analysis. NGF plasma levels were significantly lower in Rett patients with QTc interval prolongation (QTc > 0.44 sec) in comparison with Rett patients with a normal QTc interval (4.5+/-4.5 vs 11+/-8.3 pg/ml, p = 0.02). The alteration of NGF levels, observed in Rett patients with a long QTc interval, may explain the presence of an altered ventricular repolarization associated with a higher risk of cardiac arrhythmias.

Adolescent↗

PubMedDate not supplied

Nerve growth factor influences neurobehavioral development of newborn mice.

Thirty-six male pups of the CD-1 outbred strain received from postnatal day 2 to day 10 a daily subcutaneous injection of either highly purified murine Nerve Growth Factor (NGF; 5 mg/kg), cytochrome c (5 mg/kg), or saline solution. NGF-treated pups showed a slight, but significant, reduction in body weight gain and a concomitant acceleration in the appearance of early signs of neurobehavioral maturation such as righting reflex, cliff aversion, and response to tactile stimulation of the perioral area. Other responses, including the ultrasonic vocalization pattern on day 7, were unaffected or affected to a lesser extent.

Animals↗

PubMedDate not supplied

Neonatal exposure to bFGF exerts NGF-like effects on mouse behavioral development.

Brain cells are naturally exposed to a variety of trophic factors during development. Basic Fibroblast Growth Factor (bFGF), a protein found in the central nervous system (CNS) enhances both survival and proliferation of several CNS cell lines. Neonatal mice of the CD1 outbred strain were injected intracerebroventricularly (ICV) with bovine bFGF on postnatal days 2, 4, and 7. bFGF, dissolved in 25 microliters of saline, was given in the 1, 5, 25, and 1000 ng doses. Physical traits such as body weight gain, body length, and tail length were recorded from postnatal day (PND) 2 to PND 12. Neurobehavioral development was scored according to a modified Fox's Scale. The ultrasonic vocalization pattern (PND 8), homing performance (PND 10), open-field activity and exploration of a novel object (PND 18) were also assessed. Pups receiving 25 and 1000 ng doses of bFGF showed a slight but significant acceleration in the appearance of some early sensorimotor reflexes, such as weak and tactile stimulation, forelimb placing and grasping, and screen climbing, during the first postnatal weeks. The other responses were less affected or not affected at all. Data are compared with similar systemic exposure of neonatal mice to Nerve Growth Factor (NGF).

Animals↗

PubMedDate not supplied

Neonatal exposure to anti-nerve growth factor antibodies affects exploratory behavior of developing mice in the hole board.

The aim of this study was to assess in developing mice whether the neutralization of endogenous NGF following ICV administration of anti-NGF antibodies (50 micrograms/2 microliters) on postnatal days 3, 6, 9, and 12 affected locomotor activity, exploratory behavior, and response to the cholinergic blocker scopolamine. In Experiments 1 and 2 activity and age-typical scopolamine effects were evaluated on PND 13 or 17 in an automated apparatus. No significant main effect of anti-NGF treatment was found at either age. On day 13 scopolamine (0.2, 1, or 2 mg/kg) decreased locomotion in both anti-NGF and control animals. In Experiment 3, locomotion and exploratory behavior were analyzed in an open field arena or in a hole board apparatus on PND 16. No significant effects of anti-NGF treatment on general motor activity and investigation of a novel object in the open field was found, though anti-NGF animals tended to be less active than controls. In the hole board anti-NGF pups showed a different pattern of head dipping behavior from controls, exploring mainly the holes located in the periphery of the apparatus.

Animals↗

PubMedDate not supplied

Prenatal exposure to anti-HIV drugs. long-term neurobehavioral effects of lamivudine (3TC) in CD-1 mice.

The present study was aimed at investigating the long-term effects of prenatal exposure to lamivudine (3TC), an antiretroviral drug used in clinical practice alone or in combination with zidovudine (AZT) to prevent mother-to-child transmission of the HIV virus. Pregnant CD-1 mice were given per os twice daily either 3TC at different doses (125, 250, or 500 mg/kg) or vehicle solution (NaCl 0. 9%) from pregnancy day 10 to delivery. Offspring behavior was examined on postnatal day 35 in a 20-min social interaction test. At adulthood different behavioral endpoints were analyzed, including locomotor activity and exploration in an open field following administration of the muscarinic antagonist scopolamine (2 mg/kg), spatial learning in either radial arm or Morris water maze, virgin female behavior in a maternal induction test, and pain sensitivity in a hot-plate test (52 +/- 0.1 degrees C). Our findings confirm the low neurotoxicity of 3TC in comparison to AZT. However some significant behavioral alterations were found, namely (1) a decrease in immobility in the open field test, (2) an increase in the responsiveness to scopolamine shown by the 500-mg/kg 3TC mice (sniffing behavior) in the open field, and (3) a longer escape latency in the first day of the reversal phase in the Morris task (particularly marked in the 250-mg/kg treatment group). No significant changes in either pain sensitivity, social/affiliative, or maternal behavior were found, although a higher occurrence of aggressive behavior toward foster pups was noted in both 125- and 500-mg/kg 3TC females.

Animals↗

PubMedDate not supplied

Effects of prenatal AZT on mouse neurobehavioral development and passive avoidance learning.

Recent evidence has shown that perinatal administration of zidovudine (AZT) to HIV-infected mothers reduces the risk of maternal-infant transmission of the virus. Treatment of pregnant seropositive women with AZT is becoming a common medical practice, despite the paucity of information about the potential neurotoxic/behavioral-teratogenic effects of AZT on the developing organism. The aim of the present study is to evaluate in mice the short-, medium-, and long-term effects of prenatal exposure to AZT on neurobehavioral development. Pregnant mice were given 0.2, 0.4, and 2.0 mg/ml AZT in drinking water from day 10 of gestation to delivery. Offspring's viability was severely affected in the 2.0 mg/ml AZT group. Thus, behavioral analysis was carried out in offspring of 0.2 and 0.4 mg/ml AZT-treated females only. Some limited but significant alterations were found, such as stunted body weight, delayed appearance of the pole-grasping reflex, and a slight impairment in the acquisition phase of a passive avoidance response. Moreover, sexual differences in some items of the social behavior repertoire appeared to be affected by AZT treatment.

Agonistic Behavior↗

PubMedDate not supplied

Neurobehavioral effects of prenatal lamivudine (3TC) exposure in preweaning mice.

The present study provides a characterization of the behavioral changes induced in preweaning mice by prenatal exposure to lamivudine (3TC), an antiviral drug recently entered in the clinical practice to treat HIV patients. Pregnant CD1 mice were given per os bidaily either 3TC at different doses (125, 250, or 500 mg/kg) or vehicle solution (saline 0.9%) from pregnancy day 10 to delivery. Data on reproductive performance, such as gestation length, litter size, and offspring viability, were collected. Offspring were then examined for a series of different somatic and behavioral end points, including sensorimotor development, ontogenetic pattern of ultrasonic vocalization, passive avoidance learning, and locomotor activity. In the absence of gross changes in somatic and sensorimotor development, a slight change in ultrasound emission was found on postnatal day (PND) 3, with 125 and 500 mg/kg 3TC-treated offspring emitting a lower number of ultrasounds. Learning and retention performances of a passive-avoidance task on PND 20-21 were unaffected by 3TC treatment, while decreased habituation in an automated locomotor activity test was evident in male offspring exposed to 250 and 500 mg/kg 3TC.

Animals↗