Seasonal variations of DNA-adduct patterns in open field farmers handling pesticides.

Seasonal variations of DNA-adduct levels in peripheral blood cells were evaluated in open field farmers (n=26) by use of the 32P-postlabelling assay. Samples were collected before (sample S0) and during (sample S4) the period of intensive pesticide use. A similar sampling procedure was applied to a referent group (n=29).

Are cytomegalic neurons and balloon cells generators of epileptic activity in pediatric cortical dysplasia?

Purpose: Severe cortical dysplasia (CD) is characterized by the presence of cytomegalic neurons and balloon cells. These aberrant cells could participate in the generation of epileptic activity. The aim of this study was to morphologically and electrophysiologically characterize cells in pediatric CD tissue.

Pediatric cortical dysplasia: correlations between neuroimaging, electrophysiology and location of cytomegalic neurons and balloon cells and glutamate/GABA synaptic circuits.

Seizures in cortical dysplasia (CD) could be from cytomegalic neurons and balloon cells acting as epileptic 'pacemakers', or abnormal neurotransmission. This study examined these hypotheses using in vitro electrophysiological techniques to determine intrinsic membrane properties and spontaneous glutamatergic and GABAergic synaptic activity for normal-pyramidal neurons, cytomegalic neurons and balloon cells from 67 neocortical sites originating from 43 CD patients (ages 0.2-14 years).

Phase I study of docetaxel in combination with the P-glycoprotein inhibitor, zosuquidar, in resistant malignancies.

Purpose: To determine the maximum tolerated dose, dose-limiting toxicity, and pharmacokinetics of docetaxel infused over 1 hour when given in combination with oral zosuquidar to patients with resistant solid tumors.

Experimental Design: In cycle 1, patients received docetaxel alone. In subsequent cycles, zosuquidar was administered with docetaxel, which was escalated from 75 to 100 mg/m2.

Increased GABAergic function in mouse models of Huntington's disease: reversal by BDNF.

Huntington's disease (HD) is characterized by loss of striatal gamma-aminobutyric acid (GABA)ergic medium-sized spiny projection neurons (MSSNs), whereas some classes of striatal interneurons are relatively spared. Striatal interneurons provide most of the inhibitory synaptic input to MSSNs and use GABA as their neurotransmitter. We reported previously alterations in glutamatergic synaptic activity in the R6/2 and R6/1 mouse models of HD.

Human cortical dysplasia and epilepsy: an ontogenetic hypothesis based on volumetric MRI and NeuN neuronal density and size measurements.

In epilepsy patients with cortical dysplasia (CD), this study determined the probable ontogenetic timing of pathogenesis based on the number, location and appearance of neurons. Magnetic resonance imaging (MRI) determined gray and white matter volumes of affected and non-affected cerebral hemispheres, and gray and white matter neuronal-nuclear protein (NeuN) densities and sizes were assessed in epilepsy surgery patients (0.2-38 years) with CD (n = 25) and non-CD etiologies (n = 14), and compared with autopsy cases (n = 13; 0-33 years).

NMDA receptor alterations in neurons from pediatric cortical dysplasia tissue.

The subunit composition of glutamate receptors affects their functional properties, and could contribute to abnormal electrophysiology in pediatric cortical dysplasia (CD). We examined electrophysiological responses and subunit assembly of N-methyl-D-aspartate (NMDA) receptors in acutely dissociated normal-appearing pyramidal and cytomegalic neurons from CD tissue and normal-appearing pyramidal neurons from non-CD tissue. In most cytomegalic and approximately 30% of normal-appearing pyramidal neurons from CD tissue, NMDA currents showed decreased Mg(2+) sensitivity compared with neurons from non-CD tissue.

Urine mutagenicity and lymphocyte DNA damage in fruit growers occupationally exposed to the fungicide captan.

Aims: To determine haematological parameters, urine mutagenicity (on three Salmonella typhimurium strains), and DNA damage (using the comet assay) in mononuclear leucocytes of farmers before and after a one-day spraying period of pear and apple trees with the fungicide captan in usual conditions.

Methods: Fruit growers were exposed to captan during the 1998 (n = 12) and/or the 2000 spraying seasons (n = 17). Biological samples were collected on the morning of the day of spraying (S1), the evening after spraying (S2), and the morning of the day after (S3).

Interactions of heparin with human skin cells: binding, location, and transdermal penetration.

The development of new materials for tissue engineering of skin substitutes requires an increasing knowledge of their interactions with human skin cells. Since carbohydrate recognition is involved in numerous biologic processes, including skin regeneration, the aim of this study was to identify sugar receptors expressed at the surface of human dermic and epidermic cells. Binding of fluorescent sugar-polyhydroxyethylacrylamide derivatives was analyzed by flow cytofluorimetry on cultured human skin fibroblasts, keratinocytes, and melanocytes.

Long-term pregabalin treatment protects basal cortices and delays the occurrence of spontaneous seizures in the lithium-pilocarpine model in the rat.

Purpose: To determine whether a pharmacologic treatment could delay or prevent the epileptogenesis induced by status epilepticus (SE) through the protection of some brain areas, we studied the effects of the long-term exposure to pregabalin (PGB) on neuronal damage and epileptogenesis induced by lithium-pilocarpine SE.

Methods: SE was induced in adult and 21-day-old (P21) rats. At 20 min after pilocarpine, rats received 50 mg/kg PGB (pilo-preg) or saline (pilo-saline).

Morphological and electrophysiological characterization of abnormal cell types in pediatric cortical dysplasia.

The mechanisms responsible for seizure generation in cortical dysplasia (CD) are unknown, but morphologically abnormal cells could contribute. We examined the passive and active membrane properties of cells from pediatric CD in vitro. Normal- and abnormal-appearing cells were identified morphologically by using infrared videomicroscopy and biocytin in slices from children with mild to severe CD.

Urine mutagenicity of farmers occupationally exposed during a 1-day use of chlorothalonil and insecticides.

Objectives: A study was conducted to evaluate the genotoxic impregnation consecutive to a 1-day open-field spraying of pesticides.

Methods: From 14 farmers (five smokers and nine non-smokers), three urine samples were collected at the end of the spraying season: the morning (S1) of the day of spraying, the evening (S2) and the morning (S3) of the following day. A fourth sample (S0) was obtained before the pesticide-handling period.

Dynamic variations of local cerebral blood flow in maximal electroshock seizures in the rat.

Purpose: Measurement of cerebral blood flow is routinely used to locate the areas involved in generation and spread of seizures in epilepsy patients. Because the nature of the hyperperfused regions varies with the timing of injection of tracer, in this study, we used a rat model of maximal electroshock seizures to follow up the time-dependent changes in the distribution of seizure-induced cerebral blood flow (CBF) changes.

Methods: CBF was measured by the quantitative autoradiographic [14C]iodoantipyrine technique over a 30-s duration.

Biomonitoring of urine mutagenicity with the Ames test: improvement of the extraction/concentration method.

Comparative extraction efficiency of the pre-packed Bakerbond-spe-SDB-1 resin and of Amberlite-AD2 (XAD-2) resin, for the preparation of urine extracts in biomonitoring studies. Urine extracts were prepared in parallel with the Bakerbond column and with the classical XAD-2 resin from urines (1) spiked with mutagenic chemicals, (2) collected from patients after chemotherapy, and (3) from smokers. Mutagenic activities were evaluated on Salmonella typhimurium tester strains TA97a, TA98, TA100 and TA102 with and without S9 mix.

Vigabatrin protects against hippocampal damage but is not antiepileptogenic in the lithium-pilocarpine model of temporal lobe epilepsy.

In temporal lobe epilepsy (TLE), the nature of the structures involved in the development of the epileptogenic circuit is still not clearly identified. In the lithium-pilocarpine model, neuronal damage occurs both in the structures belonging to the circuit of initiation and maintenance of the seizures (forebrain limbic system) as well as in the propagation areas (cortex and thalamus) and in the circuit of remote control of seizures (substantia nigra pars reticulata). In order to determine whether protection of some brain areas could prevent the epileptogenesis induced by status epilepticus (SE) and to identify the cerebral structures involved in the genesis of TLE, we studied the effects of the chronic exposure to Vigabatrin (gamma-vinyl-GABA, GVG) on neuronal damage and epileptogenesis induced by lithium-pilocarpine SE.

Alterations of hippocampal GAbaergic system contribute to development of spontaneous recurrent seizures in the rat lithium-pilocarpine model of temporal lobe epilepsy.

Reorganization of excitatory and inhibitory circuits in the hippocampal formation following seizure-induced neuronal loss has been proposed to underlie the development of chronic seizures in temporal lobe epilepsy (TLE). Here, we investigated whether specific morphological alterations of the GABAergic system can be related to the onset of spontaneous recurrent seizures (SRS) in the rat lithium-pilocarpine model of TLE. Immunohistochemical staining for markers of interneurons and their projections, including parvalbumin (PV), calretinin (CR), calbindin (CB), glutamic acid decarboxylase (GAD), and type 1 GABA transporter (GAT1), was performed in brain sections of rats treated with lithium-pilocarpine and sacrificed after 24 h, during the silent phase (6 and 12 days), or after the onset of SRS (10-18 days after treatment).

The lesional and epileptogenic consequences of lithium-pilocarpine-induced status epilepticus are affected by previous exposure to isolated seizures: effects of amygdala kindling and maximal electroshocks.

In temporal lobe epilepsy, the occurrence of seizures seems to correlate with the presence of lesions underlying the establishment of a hyperexcitable circuit. However, in the lithium-pilocarpine model of epilepsy, neuronal damage occurs both in the structures belonging to the circuit of initiation and maintenance of the seizures (forebrain limbic system) as in the propagation areas (cortex and thalamus) and in the circuit of remote control of seizures (substantia nigra pars reticulata). To determine whether or not we could protect the brain from lesions and epileptogenesis induced by status epilepticus and identify cerebral structures involved in the genesis of epilepsy, we studied the effects of the chronic exposure to non-deleterious seizures, either focalized with secondary generalization (amygdala kindling, kindled-pilocarpine rats), or primary generalized (ear-clip electroshocks, electroshock-pilocarpine rats) on neuronal damage and epileptogenesis induced by lithium-pilocarpine status epilepticus.

Electroshocks delay seizures and subsequent epileptogenesis but do not prevent neuronal damage in the lithium-pilocarpine model of epilepsy.

Electroconvulsive therapy, which is used to treat refractory major depression in humans increases seizure threshold and decreases seizure duration. Moreover, the expression of brain derived neurotrophic factor induced by electroshocks (ECS) might protect hippocampal cells from death in patients suffering from depression. As temporal lobe epilepsy is linked to neuronal damage in the hippocampus, we tested the effect of repeated ECS on subsequent status epilepticus (SE) induced by lithium-pilocarpine and leading to cell death and temporal epilepsy in the rat.

Inhibitory effect of melatonin on 7, 12-dimethylbenz[a]anthracene-induced carcinogenesis of the uterine cervix and vagina in mice and mutagenesis in vitro.

Forty female CBA mice aged 3-4 months were exposed twice a week during 2 months to intravaginal applications of polyurethane sponges impregnated with 0.1% solution of 7,12-dimethylbenz[a]anthracene (DMBA) in triethyleneglycol. Three hours after each application the sponges were taken out.

Neuroprotective effects of chronic estradiol benzoate treatment on hippocampal cell loss induced by status epilepticus in the female rat.

Neuroprotective properties of estrogen are supported by extensive experimental evidence. In this study, the effects of estrogen were examined on the neurodegeneration secondary to status epilepticus induced by kainic acid in the rat. Chronic supplementation of ovariectomized rats with estradiol benzoate (20 microg/day) did not modify the expression of seizures monitored by electroencephalography, but significantly reduced cellular loss in the hippocampus.

[Spinal fractures in ankylosing spondylarthritis. Apropos of 4 cases].

Fractures of the spine in patients with ankylosing spondylitis may be the result of minor trauma. They may lead to severe neurological deficits. They are difficult to detect on plain radiographs and CT or MRI often are required for diagnosis.

[Clinical, electrophysiological and MRI correlations in carpal tunnel syndrome].

Unlabelled: Even though diagnosis of carpal tunnel syndrome is mainly based on clinical findings, other examinations are often useful for confirmation and management. The most useful of these examinations is EMG. However, EMG may be inconclusive and MRI may then be helpful.

[Intrathyroid parathyroid adenoma].

Parathyroid adenomas are embedded within thyroid tissue in about 2-5% of cases. Intrathyroid parathyroid adenomas are easily detected at US. As such, US should be performed prior to surgical intervention.