Fractures non traumatiques en fin de grossesse: s'agit-il toujours d'une ostéoporose? A propos de deux cas [Non-traumatic fractures at the end of a pregnancy: are there always of osteoporotic origin].

Pregnancy-associated osteoporosis usually appears during the first pregnancy and does not affect the followings. We report two cases where non-traumatic fractures have been diagnosed shortly after delivery of second pregnancies. Wide investigations could not find a cause of secondary osteoporosis. In the first case we came to the diagnosis of pregnancy-associated osteoporosis and an intravenous treatment of ibandronate has been prescribed. In the second case the bone mineral density (BMD) being almost normal and the localisation of the fracture being atypical, we concluded to a fracture of non-osteoporotic origin, probably due to mechanical stress during pregnancy. No therapy against osteoporosis has been prescribed.

Differences in Frontal Activation in Adult Patients with Schizophrenia and in Psychotic Adolescents with Schizophrenic Symptoms in Two Fmri Tasks

Background: Language processing abnormalities and inhibition difficulties are hallmark features of schizophrenia. The objective of this study is to asses the blood oxygenation level-dependent (BOLD) response at two different stages of the illness and compare the frontal activity between adolescents and adults with schizophrenia. Methods: 10 adults with schizophrenia (mean age 31,5 years) and 6 psychotic adolescents with schizophrenic symptoms (mean age 16,2 years) underwent functional magnetic resonance imaging while performing two frontal tasks. Regional activation is compared in the bilateral frontal areas during a covert verbal fluency task (letter version) and a Stroop task (inhibition task). Results: Preliminary results show poorer task performance and less frontal cortex activation during both tasks in the adult group of patients with schizophrenia. In the adolescent patients group, fMRI analysis show significant and larger activity in the left frontal operculum (Broca's area) in the verbal fluency task and greater activity in the medium cingulate during the inhibition phase of the Stroop task. Conclusions: These preliminary findings suggest a decrease of frontal activity in the course of the illness. We assume that schizophrenia contributes to frontal brain activity reduction.

Propofol anesthesia impairs the maturation and survival of adult-born hippocampal neurons.

BACKGROUND: Adult neurogenesis occurs in the hippocampus of most mammals, including humans, and plays an important role in hippocampal-dependent learning. This process is highly regulated by neuronal activity and might therefore be vulnerable to anesthesia. In this article, the authors investigated this possibility by evaluating the impact of propofol anesthesia on mouse hippocampal neurons generated during adulthood, at two functionally distinct maturational stages of their development. METHODS: Adult-born hippocampal neurons were identified using the cell proliferation marker bromodeoxyuridine or a retroviral vector expressing the green fluorescent protein in dividing cells and their progenies. Eleven or 17 days after the labeling procedure, animals (n = 3-5 animals per group) underwent a 6-h-long propofol anesthesia. Twenty-one days after labeling, the authors analyzed the survival, differentiation, and morphologic maturation of adult-born neurons using confocal microscopy. RESULTS: Propofol impaired the survival and maturation of adult-born neurons in an age-dependent manner. Anesthesia induced a significant decrease in the survival of neurons that were 17 days old at the time of anesthesia, but not of neurons that were 11 days old. Similarly, propofol anesthesia significantly reduced the dendritic maturation of neurons generated 17 days before anesthesia, without interfering with the maturation of neurons generated 11 days before anesthesia. CONCLUSIONS: These results reveal that propofol impairs the survival and maturation of adult-born hippocampal neurons in a developmental stage-dependent manner in mice.

Low density polyethylene (LDPE) passive samplers for the investigation of polychlorinated biphenyl (PCB) point sources in rivers

This study aims to provide a passive sampling approach which can be routinely used to investigate polychlorinated biphenyl (PCB) sources in rivers. The approach consists of deploying low density polyethylene (LDPE) strips downstream and upstream of potential PCB sources as well as in their water discharges. Concentrations of indicator PCBs (iPCBs) absorbed in samplers (Cs) from upstream and downstream sites are compared with each other to reveal increases of PCB levels. Cs measured in water discharges are used to determine if released amounts of PCBs are compatible with increases revealed in the river. As water velocity can greatly vary along a river stretch and influences the uptake at each site in a different way, differences in velocity have to be taken into account to correctly interpret Cs. LDPE strips were exposed to velocities between 1.6 and 37 cm s−1 using a channel system built in the field. Relationships between velocity and Cs were established for each iPCB to determine the expected change in Cs due to velocity variations. For PCBs 28 and 52, this change does not exceed a factor 2 for velocity variations in the range from 1.6 to 100 cm s−1 (extrapolated data above 37 cm s−1). For PCBs 101, 138, 153 and 180, this change only exceeds a factor 2 in the case of large velocity variations. The approach was applied in the Swiss river Venoge to first conduct a primary investigation of potential PCB sources and then conduct thorough investigations of two suspected sources.

The yield of high-density electric source imaging in focal epilepsy

Background: EEG is the cornerstone of epilepsy diagnostics and mandatory to determine the underlying epilepsy syndrome (e.g. focal vs idiopathic generalized). However, its potential as imaging tool is still underrecognized. In the present study, we aim to determine the prerequisites of maximal benefit of electric source imaging (ESI) to localize the irritative zone in patients with focal epilepsy. Methods: 150 patients suffering from focal epilepsy and with minimum 1 year post-operative follow-up were studied prospectively by reviewers blinded to the underlying diagnosis and outcome. We evaluated the influence of two important factors on sensitivity and specificity of ESI: the number of electrodes (low resolution, LR-ESI: \30 vs. high resolution, HR-ESI: 128-256 electrodes), and the use of individual MRI (i-MRI) vs. template MRI (t-MRI) as head model.Results: ESI had a sensitivity of 85% and a specificity of 87% when HR-ESI with i-MRI was used. Using LR-ESI, sensitivity decreased to 68%, or even 57% when only t-MRI was available. The sensitivity of HR-ESI/i-MRI compared favorably with those of MRI (76%), PET (69%) and ictal/interictal SPECT (64%).Interpretation: This study on a large patient group shows excellent sensitivity and specificity of ESI if 128 EEG channels or more are used for ESI and if the results are co-registered to the patient's individual MRI. Localization precision is as high as or even higher than established brain imaging techniques, providing excellent costeffectiveness in epilepsy evaluation. HR-ESI appears to be a valuable additional imaging tool, given that larger electrode arrays are easily and rapidly applied with modern EEG equipment and that structural MRI is nearly always available for these patients.

D-3 2008-2 Dependent Adult Abuse Report, January - June 2009

D-3 Dependent Adult Abuse Report

Long-term sequelae in children surviving adult respiratory distress syndrome.

Nine children surviving severe adult respiratory distress syndrome were studied 0.9 to 4.2 years after the acute illness. They had received artificial ventilation for a mean of 9.4 days, with an Fio2 greater than 0.5 during a mean time of 34 hours and maximal positive end expiratory pressure levels in the range of 8 to 20 cm H2O. Three children had recurrent respiratory symptoms (moderate exertional dyspnea and cough), and two had evidence of fibrosis on chest radiographs. All patients had abnormal lung function; the most prominent findings were ventilation inequalities, as judged by real-time moment ratio analysis of multibreath nitrogen washout curves (abnormal in eight of nine patients) and hypoxemia (seven of nine). Lung volumes were less abnormal; one patient had restrictive and two had obstructive disease. A significant correlation between intensive care measures (Fio2 greater than 0.5 in hours and peak inspiratory plateau pressure) and lung function abnormalities (moment ratio analysis and hypoxemia) was found. A possibly increased susceptibility of the pediatric age group to the primary insult or respiratory therapy of adult respiratory distress syndrome is suggested.

Thyroid hormone reduces the loss of axotomized sensory neurons in dorsal root ganglia after sciatic nerve transection in adult rat.

We have shown that a local administration of thyroid hormones (T3) at the level of transected rat sciatic nerve induced a significant increase in the number of regenerated axons. To address the question of whether local administration of T3 rescues the axotomized sensory neurons from death, in the present study we estimated the total number of surviving neurons per dorsal root ganglion (DRG) in three experimental group animals. Forty-five days following rat sciatic nerve transection, the lumbar (L4 and L5) DRG were removed from PBS-control, T3-treated as well as from unoperated rats, and serial sections (1 microm) were cut. The physical dissector method was used to estimate the total number of sensory neurons in the DRGs. Our results revealed that in PBS-control rats transection of sciatic nerve leads to a significant (P < 0.001) decrease in the mean number of sensory neurons (8743.8 +/- 748.6) compared with the number of neurons in nontransected ganglion (mean 13,293.7 +/- 1368.4). However, administration of T3 immediately after sciatic nerve transection rescues a great number of axotomized neurons so that their mean neuron number (12,045.8 +/- 929.8) is not significantly different from the mean number of neurons in the nontransected ganglion. In addition, the volume of ganglia showed a similar tendency. These results suggest that T3 rescues a high number of axotomized sensory neurons from death and allows these cells to grow new axons. We believe that the relative preservation of neurons is important in considering future therapeutic approaches of human peripheral nerve lesion and sensory neuropathy.

Immunodensity and mRNA expression of A2A adenosine, D2 dopamine, and CB1 cannabinoid receptors in postmortem frontal cortex of subjects with schizophrenia: effect of antipsychotic treatment.

RATIONALE: Dopamine D2 receptors are the main target of antipsychotic drugs. In the brain, D2 receptors coexpress with adenosine A2A and CB1 cannabinoid receptors, leading to functional interactions. OBJECTIVES: The protein and messenger RNA (mRNA) contents of A2A, D2, and CB1 receptors were quantified in postmortem prefrontal cortex of subjects with schizophrenia. MATERIALS AND METHODS: The study was performed in subjects suffering schizophrenia (n=31) who mainly died by suicide, matched with non-schizophrenia suicide victims (n=13) and non-suicide controls (n=33). The density of receptor proteins was evaluated by immunodetection techniques, and their relative mRNA expression was quantified by quantitative real-time polymerase chain reaction. RESULTS: In schizophrenia, the densities of A2A (90+/-6%, n=24) and D2-like receptors (95+/-5%, n=22) did not differ from those in controls (100%). Antipsychotic treatment did not induce changes in the protein expression. In contrast, the immunodensity of CB1 receptors was significantly decreased (71+/-7%, n=11; p<0.05) in antipsychotic-treated subjects with schizophrenia but not in drug-free subjects (104+/-13%, n=11). The relative mRNA amounts encoding for A2A, D2, and CB1 receptors were similar in brains of drug-free, antipsychotic-treated subjects with schizophrenia and controls. CONCLUSIONS: The findings suggest that antipsychotics induce down-regulation of CB1 receptors in brain. Since A2A, D2, and CB1 receptors coexpress on brain GABAergic neurons and reductions in markers of GABA neurotransmission have been identified in schizophrenia, a lower density of CB1 receptor induced by antipsychotics could represent an adaptative mechanism that reduces the endocannabinoid-mediated suppression of GABA release, contributing to the normalization of cognitive functions in the disorder.

Iowa Railroad Traffic Density, July 1, 2009

Iowa railroad traffic density.

Schizophrenia connectivity: correlation between cognitive deficits and reduced thalamo-cortical fibers

Introduction: Schizophrenia is associated with multiple neuropsychological dysfunctions, such as disturbances of attention, memory, perceptual functioning, concept formation and executive processes. These cognitive functions are reported to depend on the integrity of the prefrontal and thalamo-prefrontal circuits. Multiple lines of evidence suggest that schizophrenia is related to abnormalities in neural circuitry and impaired structural connectivity. Here, we report a preliminary case-control study that showed a correlation between thalamo-frontal connections and several cognitive functions known to be impaired in schizophrenia. Materials and Methods: We investigated 9 schizophrenic patients (DSM IV criteria, Diagnostic Interview for Genetic Studies) and 9 age and sex matched control subjects. We obtained from each volunteer a DT-MRI dataset (3 T, _ _ 1,000 s/mm2), and a high resolution anatomic T1. The thalamo- frontal tracts are simulated with DTI tractography on these dataset, a method allowing inference of the main neural fiber tracks from Diffusion MRI data. In order to see an eventual correlation with the thalamo-frontal connections, every subject performs a battery of neuropsychological tests including computerized tests of attention (sustained attention, selective attention and reaction time), working memory tests (Plane test and the working memory sub-tests of the Wechsler Adult Intelligence Scale), a executive functioning task (Tower of Hanoï) and a test of visual binding abilities. Results: In a pilot case-control study (patients: n _ 9; controls: n _ 9), we showed that this methodology is appropriate and giving results in the excepted range. Considering the relation of the connectivity density and the neuropsychological data, a correlation between the number of thalamo- frontal fibers and the performance in the Tower of Hanoï was observed in the patients (Pearson correlation, r _ 0.76, p _ 0.05) but not in control subjects. In the most difficult item of the test, the least number of fibers corresponds to the worst performance of the test (fig. 2, number of supplementary movements of the elements necessary to realize the right configuration). It's interesting to note here that in an independent study, we showed that schizophrenia patients (n _ 32) perform in the most difficult item of the Tower of Hanoï (Mann-Whitney, p _ 0.005) significantly worse than control subjects (n _ 29). This has been observed in several others neuropsychological studies. Discussion: This pilot study of schizophrenia patients shows a correlation between the number of thalam-frontal fibers and the performance in the Tower of Hanoï, which is a planning and goal oriented actions task known to be associated with frontal dysfonction. This observation is consistent with the proposed impaired connectivity in schizophrenia. We aim to pursue the study with a larger sample in order to determine if other neuropsychological tests may be associated with the connectivity density.

The murine interleukin-2 receptor gamma chain gene: organization, chromosomal localization and expression in the adult thymus.

Defects in the interleukin-2 receptor gamma (IL-2R gamma) chain in the man result in an X-linked severe combined immunodeficiency, SCIDX1, characterized by an absence of T-cell differentiation. This phenotype may result from pertubations in IL-2, IL-4-, IL-7- or IL-15-mediated signaling, as the IL-2R gamma chain forms an integral component of these receptor systems. We have isolated and characterized cDNA and genomic clones for the murine IL-2R gamma. The gene (Il2rg) is well conserved between mouse and man with respect to overall structure and size, and contains regions of high conservation in the promoter region as well. Il2rg maps to mouse X chromosome region 40, in a region of synteny with human Xq12-13.1. We have also explored the expression of the IL-2R gamma during thymocyte development. IL-2R gamma transcripts are detected in the earliest thymocyte precursor cells and persist throughout intrathymic development into the mature peripheral compartment. Genomic clones for the murine IL-2R gamma will allow for further studies on the regulation and function of this gene in vivo.