Prenatal exposure to low concentrations of carbon monoxide alters habituation and non-spatial working memory in rat offspring

Inhalation of low concentrations (75 and 150 ppm) of carbon monoxide (CO) by pregnant rats from days 0 to 20 of gestation leads to alterations in habituation and working memory in young adult male offspring subjected to the novel exploration object test. In particular, lack of habituation upon the second presentation of the objects and failure in the ability to discriminate between the novel and the familiar object were found in CO (75 and 150 ppm)-exposed offspring. These alterations were not accompanied by changes in spontaneous motor activity (open field test). The subtle behavioral deficits observed in the present study have been produced by prenatal exposure to CO levels resulting in maternal blood carboxyhaemoglobin (HbCO) concentrations equivalent to those observed in human cigarette smokers. (C) 1999 Elsevier Science B.V. All rights reserved

The functional anatomy of the cerebrocerebellar circuit: A review and new concepts

The cerebrocerebellar circuit is a feedback circuit that bidirectionally connects the neocortex and the cerebellum. According to the classic view, the cerebrocerebellar circuit is specifically involved in the functional regulation of the motor areas of the neocortex. In recent years, studies carried out in experimental animals by morphological and physiological methods, and in humans by magnetic resonance imaging, have indicated that the cerebrocerebellar circuit is also involved in the functional regulation of the nonmotor areas of the neocortex, including the prefrontal, associative, sensory and limbic areas. Moreover, a second type of cerebrocerebellar circuit, bidirectionally connecting the hypothalamus and the cerebellum, has been detected, being specifically involved in the regulation of the hypothalamic functions. This review analyzes the morphological features of the centers and pathways of the cerebrocerebellar circuits, paying particular attention to their organization in different channels, which separately connect the cerebellum with the motor areas and nonmotor areas of the neocortex, and with the hypothalamus. Actually, a considerable amount of new data have led, and are leading, to profound changes on the views on the anatomy, physiology, and pathophysiology of the cerebrocerebellar circuits, so much they may be now considered to be essential for the functional regulation of many neocortex areas, perhaps all, as well as of the hypothalamus and of the limbic system. Accordingly, clinical studies have pointed out an involvement of the cerebrocerebellar circuits in the pathophysiology of an increasing number of neuropsychiatric disorders

DETECTION LIMITS OF DIFFERENT APPROACHES IN BEHAVIORAL TERATOLOGY, AND CORRELATION OF EFFECTS WITH NEUROCHEMICAL PARAMETERS

Five laboratories collaborated in the evaluation of detection limits of different testing concepts in behavioral teratology. In one laboratory, rat dams were treated by gavage with five doses of methylmercury (0.0, 0.025, 0.05, 0.5, and 5.0 mg/kg/day). The treatment period was restricted to days 6 to 9 of gestation. The usual reproduction parameters were assessed in the dams. The offspring (88-99 per group) were subjected to a routine developmental and behavioral testing battery. After completion of these tests, random samples of the animals were further investigated in four other laboratories using the following techniques: auditory startle habituation, visual discrimination and figure-8 activity monitor; wheel-shaped activity monitor and spatial alternation operant conditioning; two-compartment locomotor activity, passive avoidance and male ultrasonic vocalization during sexual behavior; assays of the weight of different brain areas, their glial fibrillary acidic (GFA) protein and S-100 protein concentration. The following dose-dependent effects were noted in ascending dose sensitivity order: delayed vaginal opening; increased and more variable passiveness in spatial alternation; impaired swimming behavior, increased GFA protein concentration in the cerebellar vermis; increased auditory startle amplitude, decreased intertrial interval pokes in the visual discrimination test, increased percentage of visits in passive area of figure-8 activity monitor, increased path iteration frequencies and decreased local activity in the wheel-shaped activity monitor, decreased locomotor activity in the two-compartment monitor, increased cerebellar vermis weight, and decreased S-100 protein in the hippocampus. Therefore, this study showed comparable sensitivities for the behavioral testing battery, for some automated multiparametric test systems and for the neurochemical assays. © 1988

Prenatal exposure to a cannabinoid agonist produces memory deficits linked to dysfunction in hippocampal long-term potentiation and glutamate release

To investigate the possible long-term consequences of gestational exposure to cannabinoids on cognitive functions, pregnant rats were administered with the CB1 receptor agonist WIN 55,212-2 (WIN), at a dose (0.5 mg/kg) that causes neither malformations nor overt signs of toxicity. Prenatal WIN exposure induced a disruption of memory retention in 40- and 80-day-old offspring subjected to a passive avoidance task. A hyperactive behavior at the ages of 12 and 40 days was also found. The memory impairment caused by the gestational exposure to WIN was correlated with alterations of hippocampal long-term potentiation (LTP) and glutamate release. LTP induced in CA3–CA1 synapses decayed faster in brain slices of rats born from WIN-treated dams, whereas posttetanic and short-term potentiation were similar to the control group. In line with LTP shortening, in vivo microdialysis showed a significant decrease in basal and K(+)-evoked extracellular glutamate levels in the hippocampus of juvenile and adult rats born from WIN-treated dams. A similar reduction in glutamate outflow was also observed in primary cell cultures of hippocampus obtained from pups born from mothers exposed to WIN. The decrease in hippocampal glutamate outflow appears to be the cause of LTP disruption, which in turn might underlie, at least in part, the long-lasting impairment of cognitive functions caused by the gestational exposure to this cannabinoid agonist. These findings could provide an explanation of cognitive alterations observed in children born from women who use marijuana during pregnancy

Dental and Maxillofacial Alterations in Patients Affected From Odontochondrodysplasia: A Rare Case Report and Review of Literature

INTRODUCTION: This paper has evaluated the dental and or facial disorders associated to Goldblatt syndrome, also known as odontochondrodysplasia. AIM: We report the analysis performed on a female young patient affected by this disease. We analyzed her dental and or facial features. MATERIALS AND METHODS: We adopted several diagnostic criteria: firstly, we performed radiographic investigations, followed by rhinomanometric measurements and by clinical analysis performed in order to determine the salivary flow in this typology of patients. The evidences obtained after a careful clinical, anamnestic, and radiographic analysis of our female patient allowed us to identify a number of odontostomatologic features, which are very likely to be related to this syndrome. Our patient showed some pathognomonic signs of odontochondrodysplasia already identified in the literature, that is, pectus carinatum, joint hyperextensibility, coxa valga and genu valgum, upper and lower limb asymmetry, and vertebral abnormalities. Moreover, we focused our attention on those odontostomatologic aspects that had never been analyzed by other reports in the literature: dentinogenesis imperfecta, ligamentous hyperlaxity of all joints and of temporomandibular joints in particular, poor lip competence, ogival palate, and oral respiration. Besides these, dental crowding and other important elements were identified through cephalometric measurements. DISCUSSION AND CONCLUSIONS: In the light of all these elements and of their comparison with the existing literature, it is possible to stereotype a few recurrent odontostomatologic and systemic-generalized features in patients with odontochondrodysplasia, which can be considered as closely associated with this syndrome

Drain tip cultures do not predict infections in primary total knee arthroplasty

The possibility to predict surgical site infections development could be of high prognostic value. We aimed to investigate whether cultures obtained from the tip of the closed passive wound drain may provide early signs of progression towards periprosthetic joint infections