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Slow firing septal neurons modulate hippocampal and neocortical functions. Electrophysiologically, it is unclear whether slow firing neurons belong to a homogeneous neuronal population. To address this issue, whole-cell patch recordings and neuronal reconstructions were performed on rat brain slices containing the medial septum/diagonal band complex (MS/DB). Slow firing neurons were identified by their low firing rate at threshold (5 Hz) and lack of time-dependent inward rectification (Ih). Unsupervised cluster analysis was used to investigate whether slow firing neurons could be further classified into different subtypes. The parameters used for the cluster analysis included latency for first spike, slow after-hyperpolarizing potential, maximal frequency and action potential (AP) decay slope. Neurons were grouped into three major subtypes. The majority of neurons (55%) were grouped as cluster I. Cluster II (17% of neurons) exhibited longer latency for generation of the first action potential (246.5+/-20.1 ms). Cluster III (28% of neurons) exhibited higher maximal firing frequency (25.3+/-1.7 Hz) when compared with cluster I (12.3+/-0.9 Hz) and cluster II (11.8+/-1.1 Hz) neurons. Additionally, cluster III neurons exhibited faster action potentials at suprathreshold. Interestingly, cluster II neurons were frequently located in the medial septum whereas neurons in cluster I and III appeared scattered throughout all MS/DB regions. Sholl's analysis revealed a more complex dendritic arborization in cluster III neurons. Cluster I and II neurons exhibited characteristics of "true" slow firing neurons whereas cluster III neurons exhibited higher frequency firing patterns. Several neurons were labeled with a cholinergic marker, Cy3-conjugated 192 IgG (p75NTR), and cholinergic neurons were found to be distributed among the three clusters. Our findings indicate that slow firing medial septal neurons are heterogeneous and that soma location is an important determinant of their electrophysiological properties. Thus, slow firing neurons from different septal regions have distinct functional properties, most likely related to their diverse connectivity.

Methylmalonic acid (MMA) is an endogenous convulsing compound that accumulates in methylmalonic acidemia, an inborn error of the metabolism characterized by severe neurological dysfunction, including seizures. The mechanisms by which MMA causes seizures involves the activation of the N-methyl-D-aspartate (NMDA) receptors, but whether GABAergic mechanisms are involved in the convulsions induced by MMA is not known. Therefore, in the current study we investigated the involvement of GABAergic mechanisms in the convulsions induced by MMA. Adult rats were injected (i.c.v.) with muscimol (46 pmol/1 microl), baclofen (0.03, 0.1 and 0.3 micromol/1 microl), MK-801 (6 nmol/1 microl), pyridoxine (2 micromol/4 microl) or physiological saline (0.15 micromol/1 microl). After 30 min, MMA (0.3, 0.1 and 3 micromol/1 microl) or NaCl (6 micromol/1 microl, i.c.v.) was injected. The animals were immediately transferred to an open field and observed for the appearance of convulsions. After behavioral evaluation, glutamic acid decarboxylase (GAD) activity was determined in cerebral cortex homogenates by measuring the 14CO2 released from l-[14C]-glutamic acid. Convulsions were confirmed by electroencephalographic recording in a subset of animals. MMA caused the appearance of clonic convulsions in a dose-dependent manner and decreased GAD activity in the cerebral cortex ex vivo. GAD activity negatively correlated with duration of MMA-induced convulsions (r=-0.873, P

Epilepsy is characterized by hyperexcitability of hippocampal networks, excessive release of glutamate, and progressive neurodegeneration. Presynaptic group II metabotropic receptors (mGluR2 and mGluR3) are among different mechanisms that modulate presynaptic release of glutamate, especially at the mossy fibers in the hippocampus. Here, we explore whether mGluR2/3 expression is affected in a rat model of temporal lobe epilepsy obtained via pilocarpine-induced status epilepticus (SE). Immunohistochemical assays were performed in age-matched controls and two groups of epileptic rats sacrificed at 25-35 days (1 month post-SE) and at 55-65 days (2 months post-SE) following SE onset. A dramatic lessening of mGluR2/3 immunofluorescence was observed at CA1 and CA3 stratum lacunosum/molecular (SLM) declining to 60% and 68% of control values in 1-month and 2-month post-SE, respectively. Additionally, thickness of mGluR2/3-stained SLM layer narrowed up to 70% of controls indicating atrophy at this branch of the perforant path. Epileptic rats exhibited a marked and progressive down-regulation of mGluR2/3 expression in mossy fiber at hilus and CA3 stratum lucidum in contrast with an enhanced expression of vesicular glutamate transporter type 1 (VGluT1) at the mossy fibers. Intense VGluT1 punctated staining was detected at the inner third molecular layer indicating glutamatergic sprouting. In the molecular layer, mGluR2/3 labeling slightly declined in the 1-month post-SE group but then increased in the 2-month post-SE group although it was diffusely distributed. Down-regulation of mGluR2/3 at the mossy fibers and the SLM may render epileptic hippocampal networks hyperexcitable and susceptible to glutamate-mediated excitotoxicity and neurodegeneration.

We apply the Time Dependent Convection (TDC) treatment presented in Grigahcene et al. (2005) to the study of Pre-main sequence pulsating stars. The stabilization of the p-modes at the red edge of the Instability Strip (IS) is obtained by our models. The theoretical IS obtained with Mixing Length (ML) parameter α =1.8 is compared to observations and a good agreement is obtained.

The problem of the interaction between convection and pulsations is considered. A precise modeling of this interaction is required for the seismic study of stars with non-negligible convective envelope. After a short introduction to the Time-Dependent Convection theory of Gabriel (1996) and Grigahc ene et al. (2005), we give a summary of the main results obtained with this treatment for Sct, Dor and solar-like stars.

Multi-site and multi-year differential photometry of the triple star DG Leo reveals a complex frequency spectrum that can be modelled as the combination of at least three Delta Scuti type frequencies in the range 11.5-13 c/d (with semi-amplitudes of 2-7 mmag) and a superimposed slow variability of larger amplitude. The period of the slow variation fits very well with half the orbital period of the inner spectroscopic binary indicating the presence of ellipsoidal variations caused by the tidally deformed components in a close configuration. These findings, together with the results of a recent spectroscopic analysis (showing that the system consists of a pair of mild Am stars and one A-type component of normal solar composition), infer that DG Leo is an extremely interesting asteroseismic target. Identification of which component(s) of this multiple system is (or are) pulsating and determination of the excited pulsation modes will both contribute to a much better understanding of the non-trivial link between multiplicity, chemical composition, rotation, and pulsation in the lower part of the classical Cepheid instability strip., 10 pages, 5 Postscript figures, uses rotate.sty. Astronomy and Astrophysics, in press (2005)

International audience; We apply for the first time the time-dependent convection (TDC) treatment of Gabriel and Grigahcène et al. to the photometric mode identification in gamma Doradus (gamma Dor) stars. We consider the influence of this treatment on the theoretical amplitude ratios and phase differences. Comparison with the observed amplitudes and phases of the stars gamma Dor, 9 Aurigae, HD 207223 = HR 8330, HD 12901 and 48501 is presented and enables us to identify the degree l of the pulsation modes for four of them. We also determine the mode stability for different models of these stars. We show that our TDC models agree better with observations than with frozen convection models. Finally, we compare the results obtained with different values of the mixing-length parameter alpha.

International audience; The effect of rotation on the Frequency Ratio Method (Moya et al. 2005, A&A, 432, 189) is examined. Its applicability to observed frequencies of rotating gamma Doradus stars is discussed taking into account the following aspects: the use of a perturbative approach to compute adiabatic oscillation frequencies; the effect of rotation on the observational Brunt-Väisälä integral determination and finally, the problem of disentangling multiplet-like structures from frequency patterns due to the period spacing expected for high-order gravity modes in asymptotic regime. This analysis reveals that the FRM produces reliable results for objects with rotational velocities up to 70 {km s-1}, for which the FRM intrinsic error increases one order of magnitude with respect to the typical FRM errors given in Moya et al. (2005, A&A, 432, 189). Our computations suggest that, given the spherical degree l identification, the FRM may be discriminating for m=0 modes, in the sense that the method avoids any misinterpretation induced by the presence of rotationally split multiplet-like structures, which reinforces the robustness of the method. However, if l is unknown, such discrimination is not ensured. In order to check the FRM in presence of slow-moderate rotation, we have applied it to the three observed frequencies of the slowly rotating ({v sin i}=29 {km s-1}) gamma Doradus star HD 48501.

En este art´ #305;culo se presenta un m´etodo para determinar los par´ametros del atractor de R¨ossler de forma muy aproximada, por medio de la observaci´on de una variable disponible. Se demuestra que el sistema es algebraicamente observable e identificable con respecto a la salida elegida. Este hecho permite construir una parametrizaci´on diferencial de la salida y de sus respectivas derivadas. A partir de esta parametrizaci´on, se establece un esquema de identificaci´on basado en el m´etodo de m´ #305;nimos cuadrados y la soluci´on es encontrada por un algoritmo gen´etico.

We undertook a multisite photometric campaign for the Beta Cephei star Nu Eridani. More than 600 hours of differential photoelectric uvyV photometry were obtained with 11 telescopes during 148 clear nights. The frequency analysis of our measurements shows that the variability of Nu Eri can be decomposed into 23 sinusoidal components, eight of which correspond to independent pulsation frequencies between 5 - 8 c/d. Some of these are arranged in multiplets, which suggests rotational m-mode splitting of nonradial pulsation modes as the cause. If so, the rotation period of the star must be between 30 - 60 d. One of the signals in the light curves of Nu Eri has a very low frequency of 0.432 c/d. It can be a high-order combination frequency or, more likely, an independent pulsation mode. In the latter case Nu Eri would be both a Beta Cephei star and a slowly pulsating B (SPB) star. The photometric amplitudes of the individual pulsation modes of Nu Eri appear to have increased by about 20 per cent over the last 40 years. So do the amplitudes of the dominant combination frequencies of the star. Among the latter, we only could identify sum frequencies with certainty, not difference frequencies, which suggests that neither light-curve distortion in its simplest form nor resonant mode coupling are their single cause. One of our comparison stars, Mu Eridani, turned out to be variable with a dominant time scale of 1.62 d. We believe that it is either an SPB star just leaving its instability strip or that its variations are of rotational origin., Comment: 10 pages, 5 figures

The activities related to the preparation of the asteroseismic, photometric space mission COROT are described. Photoelectric observations, wide--field CCD photometry, uvbyB calibrations and further time--series have been obtained at different observatories and telescopes. They have been planned to complete the COROT programme in the direction of the galactic Anticenter. In addition to suitable asteroseismic targets covering the different evolutionary stages between ZAMS and TAMS, we discovered several other variable stars, both pulsating and geometrical. We compared results on the incidence of variability in the galactic Center and Anticenter directions. Physical parameters have been obtained and evolutionary tracks fitting them have been calculated. The peculiarities of some individual stars alre pointed out. Paper based on observations collected at the San Pedro Martir, Sierra Nevada, Teide, La Silla, Haute-Provence and Roque de Los Muchachos (Telescopio Nazionale Galileo and Mercator telescopes) observatories., Comment: 13 pages, 9 figures. Accepted for The Astronomical Journal (2005 May volume)

HD34282 has been found to pulsate during a systematic search for short-term photometric variability in Herbig Ae/Be stars with the goal of determining the position and size of the pre-Main Sequence instability strip. Simultaneous Stromgren photometry is used in the frequency analysis, yielding two frequencies with values of ν1 = 79.5 and ν2 = 71.3 cycle d −1. The main period, with a value of 18.12 min, represents the shortest period observed up to now for a δ Scuti-type pulsator. A preliminary seismic modelling, including instability predictions and rotation effects, has been attempted. Both, Main Sequence and pre-Main Sequence models predict modes in the range of 56 to 82 cycle d−1 (between 648 and 949 μHz), corresponding to oscillations of radial order n from 6 to 8. The mode identification is not discriminating due to the large error bars attached to the data, therefore, all possible non-radial and radial modes up to = 3 are compatible with the observed oscillations.

HD 34282 has been found to pulsate during a systematic search for short-term photometric variability in Herbig Ae/Be stars with the goal of determining the position and size of the pre-main sequence instability strip. Simultaneous Stromgren photometry is used in the frequency analysis, yielding two frequencies with values of nu1=79.5 and nu2=71.3 c/d. The light curve with the largest amplitude is that of the u band. This behaviour, which is not common for delta Scuti stars, is explained as pulsation in a high radial order in stars near the blue edge of the instability strip. The main period, with a value of 18.12 min, represents the shortest period observed so far for a delta Scuti-type pulsator. A seismic modelling, including instability predictions and rotation effects, has been attempted. It is found that both main sequence and pre-main sequence models predict modes in the range of 56 to 82 c/d (between 648 and 949 microHz), corresponding to oscillations of radial order n from 6 to 8. The highest of the observed frequencies only becomes unstable for models of low metallicity, in agreement with results from spectroscopic measurements., 5 pages, 5 figures, Accepted by MNRAS

Succinate is a dicarboxylic acid that accumulates due to succinate dehydrogenase inhibition by malonate and methylmalonate exposure. These neurotoxins cause increased excitability and excitotoxic damage, which can be prevented by administering high amounts of succinate. In the present study we investigated whether succinate alters hippocampal field excitatory post-synaptic potentials. Bath application of succinate at intermediate concentrations (0.3–1 mM) increased the slope of field excitatory post-synaptic potentials in hippocampal slices, and at high concentrations (above 1 mM) did not alter or decrease field excitatory post-synaptic potentials slope. Succinate-induced enhancement of field excitatory post-synaptic potentials slope was abolished by the addition of d -2-amino-5-phosphonovaleric acid (50 μM) to the perfusate, supporting the involvement of N-methyl- d -aspartate receptors in the excitatory effect of this organic acid. Accordingly, succinate (0.8–7.5 μmol) i.c.v. administration caused dose-dependent convulsive behavior in mice. The i.c.v. co-administration of MK-801 (7 nmol) fully prevented succinate-induced convulsions, further suggesting the involvement of N-methyl- d -aspartate receptors in the convulsant action of succinate. Our data indicate that accumulation of moderate amounts of succinate may contribute to the excitotoxicity induced by succinate dehydrogenase inhibitors, through the activation of N-methyl- d -aspartate receptors.

"Se ha obtenido fotometr??a fotoel?ectrica uvby para el sistema estelar triple DG Leo desde dos diferentes observatoriosequipados con instrumentaci?on semejante. El an?alisis preliminar de per??odos indica la presencia deal menos 3 frecuencias pr?oximas (10-12 c/d, 3-6 mmag) en la ? Scuti y una variaci?on lenta. Esta variaci?onlenta concuerda muy bien con la mitad del per??odo ?orbital de la binaria espectrosc?opica; el nivel de ruido en elespectro de amplitudes es de 3"

A method for obtaining asteroseismological information of a Gamma Doradus oscillating star showing at least three pulsation frequencies is presented. This method is based on a first-order asymptotic g-mode expression, in agreement with the internal structure of Gamma Doradus stars. The information obtained is twofold: 1) a possible identification of the radial order n and degree l of observed frequencies (assuming that these have the same l), and 2) an estimate of the integral of the buoyancy frequency (Brunt-Vaisala) weighted over the stellar radius along the radiative zone. The accuracy of the method as well as its theoretical consistency are also discussed for a typical Gamma Doradus stellar model. Finally, the frequency ratios method has been tested with observed frequencies of the Gamma Doradus star HD 12901. The number of representative models verifying the complete set of constraints (the location in the HR diagram, the Brunt-Vaisala frequency integral, the observed metallicity and frequencies and a reliable identification of n and l) is drastically reduced to six., Comment: 11 pages, 12 figures

International audience; We present the first results of a 2-year high-resolution spectroscopy campaign of 59 candidate $\gamma$ Doradus stars which were mainly discovered from the HIPPARCOS astrometric mission. More than 60% of the stars present line profile variations which can be interpreted as due to pulsation related to $\gamma$ Doradus stars. For all stars we also derived the projected rotation velocity (up to more than 200 km s -1). The amplitude ratios $2K/\Delta m$ for the main HIPPARCOS frequency are in the range 35-96 km s -1 mag -1. About 50% of the candidates are possible members of binary systems, with 20 stars being confirmed $\gamma$ Doradus. At least 6 stars present composite spectra, and in all but one case (for which only one spectrum could be obtained), the narrow component shows line profile variations, pointing towards an uncomfortable situation if this narrow component originates from a shell surrounding the star. This paper is the first of a series concerning mode identification using both photometric and spectroscopic methods for the confirmed $\gamma$ Doradus stars of the present sample.

Idiopathic velopalatine palsy is a condition of unknown etiology and is rarely seen in childhood. Consequently, diagnosis requires a high degree of suspicion. We report a case of sudden onset dysfunction of the lower cranial pairs (IX and X) in a 5-year-old girl who was previously asymptomatic. The clinical course was favorable and the results of complementary investigations were normal and the patient was diagnosed with velopalatine palsy. Based on this case, we aim to report our experience of this condition and provide a review of the literature. This disease should be suspected in patients aged between 5 and 15 years old who present a palsy of the IX and X cranial nerves of sudden onset and without any other symptoms in order to rationalize diagnostic and therapeutic tools. Treatment is based on support measures. The prognosis is excellent, with a high percentage of complete recovery and absence of recurrences.

We tested the hypothesis that endogenous N-acetylaspartylglutamate (NAAG) presynaptically inhibits glutamate release at mossy fiber-CA3 synapses. For this purpose, we made use of 2-(3-mercaptopropyl)pentanedioic acid (2-MPPA), an inhibitor of glutamate carboxypeptidase II [GCP II; also known as N-acetylated alpha-linked acidic dipeptidase (NAALADase)], the enzyme that hydrolyzes NAAG into N-acetylaspartate and glutamate. Application of 2-MPPA (1–20 μM) had no effect on intrinsic membrane properties of CA3 pyramidal neurons recorded in vitro in whole cell current- or voltage-clamp mode. Bath application of 10 μM 2-MPPA suppressed evoked excitatory postsynaptic current (EPSC) amplitudes. Attenuation of EPSC amplitudes was accompanied by a significant increase in paired-pulse facilitation (50-ms interpulse intervals), suggesting that a presynaptic mechanism is involved. The group II metabotropic glutamate receptor (mGluR) antagonist 2 S-2-amino-2-(1 S,2 S-2-carboxycyclopropyl-1-yl)-3-(xanth-9-y l) propanoic acid (LY341495) prevented the 2-MPPA-dependent suppression of EPSC amplitudes. 2-MPPA reduced the frequencies of TTX-insensitive miniature EPSCs (mEPSC), without affecting their amplitudes, further supporting a presynaptic action for GCP II inhibition. 2-MPPA-induced reduction of mEPSC frequencies was prevented by LY341495, reinforcing the role of presynaptic group II mGluR. Because GCP II inhibition is thought to increase NAAG levels, these results suggest that NAAG suppresses synaptic transmission at mossy fiber-CA3 synapses through presynaptic activation of group II mGluRs.

We present an improved version of the method of photometric mode identification based upon the inclusion of non-adiabatic eigenfunctions determined in the stellar atmosphere, according to the formalism recently proposed by Dupret et al. (2002). We apply our method to β Cephei, Slowly Pulsating B, δ Scuti and γ Doradus stars. Besides identifying the degree l of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on the metallicity for β Cephei and SPBs, the characteristics of the superficial convection zone for δ Scuti and γ Doradus stars and the limb-darkening law.

By pursuing the goal to find new variables in the COROT field-of-view we characterised a sample of stars located in the lower part of the instability strip. Our sample is composed of stars belonging to the disk population in the solar neighbourhood. We found that 23% of the stars display multiperiodic light variability up to few mmag of amplitude. uvbyBeta photometry fixed most of the variables in the middle of the instability strip and high-resolution spectroscopy established that they have vsin i>100 km/s. The comparison with delta Sct stars in the whole Galaxy shows slightly different features, i.e., most delta Sct stars have a 0.05-mag redder (b-y)_0 index and lower vsin i values. Additional investigation in the open cluster NGC 6633 confirms the same incidence of variability, i.e., around 20%. The wide variety of pulsational behaviours of delta Sct stars (including unusual objects such as a variable beyond the blue edge or a rapidly rotating high-amplitude pulsator) makes them very powerful asteroseismic tools to be used by COROT. Being quite common among bright stars, delta Sct stars are suitable targets for optical observations from space., 9 pages, 9 figures Accepted for publication in Astronomy & Astrophysics, Main Journal

In this study we investigated the role of endogenous endothelin in the cardiovascular response to acute stress, ie mild footshocks in conscious rats. Footshock-stress significantly increased mean arterial pressure and heart rate (P0.05). Peripheral or intracerebroventricular (IVT) administration of BQ 788, a selective antagonist of ET(B) receptor, did not alter pressor response to footshocks. Intraperitoneal injections of BQ 123 (1 mg/kg), a selective antagonist of the ET(A)-receptor, had a tendency to decrease, while BQ 123 (203 ng/5 microl) IVT administration significantly reduced the pressor response to footshocks (-12 mm Hg, P0.001). Neither ET(A) nor ET(B) antagonists, when injected centrally or peripherally, altered basal blood pressure or heart rate. Our results may indicate a role of brain endothelin in the sympathetic mediated cardiovascular response to stress, via stimulation of ET(A) receptor.

The results of a multisite photometric campaign of Theta2 Tau are reported. This binary system consists of evolved and main-sequence A stars inside the instability strip. The 12th Delta Scuti Network campaign included 152 hours of high-precision photometry obtained at four observatories. This leads to the derivation of 11 frequencies of pulsation in the 10.8 to 14.6 c/d range. These frequencies confirm the results from previous Earth-based (1982-1986) as well as satellite (2000) photometry,although amplitude variability on a time scale of several years is present. We show that at least two high frequencies (26.18 and 26.73 c/d are also present in Theta 2 Tau. Arguments are given that these high frequencies originate in the main-sequence companion and are not combination frequencies, fi+fj, from the primary. Models for both the primary and the secondary components were checked for the instability against radial and nonradial oscillations. All hot models of the primary with Teff > 8000K are stable in the observed frequency range. The best fit between the theoretical and observed frequency ranges is achieved by models with Teff approximately equal to 7800K (or slightly higher), in agreement with photometric calibrations. The instability range spans two or three radial orders in the range p4 to p6 for radial modes. Post-main-sequence models (with or without overshooting) are preferable for the primary, but main-sequence models with overshooting cannot be excluded. For the less luminous secondary component the instability range is wider and spans 5 to 7 radial orders from p2 to p8. The observed frequencies lie around radial modes p5 to p6. The main uncertainties of these results are caused by a simple treatment of the convective flux in the hydrogen ionization zone., 11 pages, 7 figures, 4 tables

One of the goals of the ground-based support program for the COROT and MONS/Roemer satellite missions is to select and characterise suitable target stars for the part of the missions dedicated to asteroseismology. While the global atmospheric parameters may be determined with good accuracy from the Stromgren indices, careful abundance analysis must be made for the proposed main targets. This is a time consuming process considering the long list of primary and secondary targets. We have therefore developed new software called VWA for this task. The VWA automatically selects the least blended lines from the atomic line database VALD, and consequently adjusts the abundance in order to find the best match between the calculated and observed spectra. The variability of HD 49434 was discovered as part of COROT ground-based support observations. Here we present a detailed abundance analysis of HD 49434 using VWA. For most elements we find abundances somewhat below the Solar values, in particular we find [Fe/H] = -0.13(14). We also present the results from the study of the variability that is seen in spectroscopic and photometric time series observations. From the characteristics of the variation seen in photometry and in the line profiles we propose that HD 49434 is a variable star of the gamma Doradus type., 10 pages, 6 figures

The trans-activator protein Tat of the human immunodeficiency virus type 1 (HIV-1) is regarded as an injurious molecule in the pathogenesis of HIV-1 associated encephalopathy (HIVE). We investigated the effects of Tat on neuroligand-induced intracellular Ca2+ increase in cultured astroglial cells. Rat cortical astrocytes, human glioblastoma cells and glial restricted precursor cells, from a human embryonic teratocarcinoma cell line, were incubated with recombinant Tat (100 ng/mL for 60 min) which induced a significant reduction of glutamate or ATP-induced intracellular Ca2+ increase ("glutamate response", "ATP response"). The reduction of the glutamate response was also observed following cell incubation with cell extracts of HeLa-T4+ cells transiently transfected with an expression plasmid coding for Tat. However, inactivation of the transcriptional trans-activity of Tat, by using a mutant form of Tat, as well as inhibition of de novo protein synthesis by cycloheximide abolished the effect on the glutamate response. This suggests that Tat acts upon induction of a so far unknown cellular gene whose gene product causes the reduction of glutamate responses. As the effect of Tat resembles the effect of TNFalpha on glutamate responses [Köller et al. (2001) Brain Res., 893, 237-243] which is locally released within the brains of HIVE patients, we also tested for synergistic effects of Tat and TNFalpha on the glutamate response. Low concentrations of Tat in combination with subthreshold concentrations of TNFalpha also elicited a marked reduction of astroglial glutamate responses. Our data suggest that Tat and TNFalpha, both by itself and synergistically, induce astroglial dysfunction.

Die Fahrtauglichkeit ist bei mittelschweren und schweren psychischen Erkrankungen sowie zu Beginn einer medikamentosen Therapie in der Regel nicht gegeben.

Die nachfolgenden Tabellen (modifiziert nach Benkert, Hippius 2000) fassen die notwendigen Kontrollen zusammen.

T A multisite campaign of BI CMi was carried out with excellent frequency resolution and high photometric accuracy from 1997 to 2000, including two long observing seasons. 29 pulsation frequencies could be extracted from the 1024 h (177 nights) of photometry used. The detected frequencies include 20 pulsation modes in the main pulsation frequency range from 4.8 to 13.0 cycle d - 1 (55 to 150 μHz), eight linear combinations of these frequencies, and a very low frequency at 1.66 cycle d - 1 . Since the value of the low frequency at 1.66 cycle d - 1 cannot be identified with a linear combination of other frequencies, g-mode pulsation is suspected, but rotational modulation of abundance spots cannot be ruled out. BI CMi, which is situated near the cool edge of the classical instability strip, may be both a 8 Scuti and a γ Doradus star. Another outstanding property of BI CMi is the presence of a number of close frequency pairs in the power spectrum with separations as small as 0.01 cycle d - 1 . A rotational velocity of v sin i = 76 ′ 1 km s - 1 was determined from a high-dispersion spectrum. From phase differences, the dominant modes can be identified with values from 0 to 2. The spectral type and evolutionary status of BI CMi are examined.

Die Verordnung von Psychopharmaka wahrend Schwangerschaft und Stillzeit setzt stets ein sorgfaltiges Abwagen zwischen der pra- und postnatalen Exposition des Kindes auf der einen Seite und dem Risiko der Mutter andererseits (Wiedererkrankung nach Absetzen der Medikation, verzogerte Gesundung bei Therapie ohne Psychopharmaka etc.) voraus.

Wenn moglich, sollte die Behandlung mit nur einem Psychopharmakon erfolgen,da sich der Metabolismus mehrerer psychoaktiver Medikamente, v.a. der Abbau in der Leber, wechselseitig erheblich beeinflusst, sodass bei mehreren Psychopharmaka oft Wechselwirkungen (z.B. verstarkter sedierender Effekt etc.) auftreten. Nebenwirkungen konnen bei einer Monotherapie klar zugeordnet werden.

The need for a proper interpolation method for data coming from space missions like CoRoT is emphasized. A new gap-filling method is introduced which is based on auto-regressive moving average interpolation (ARMA) models. The method is tested on light curves from stars observed by the CoRoT satellite, filling the gaps caused by the South Atlantic Anomaly.

The observations were carried out in August, 1983 using the 75 cm telescope at Sierra Nevada Observatory in Spain. This telescope is equipped with a six-channel uvbyβ photometer for simultaneous measurements in uvby and the narrow and wide Hβ channels, respectively. The observations were collected during four nights in the four uvby filters and one more night was devoted to measuring β Cas in the n and w bands of the Hβ Crawford system. In all cases, a calibrated neutral filter was used for β Cas. The comparison star was Cl=HR 9085 (V=5.m55, F0III).The analysis of frequencies was carried out using the Discrete Fourier Transform method, as described in López de Coca et al. (1984), to the observational uvby points collected. The periodograms showed a principal peak at v=9.91 cd−l. After prewhitening for this frequency, the resulting periodograms did not show any trace of another peak, suggesting the monoperiodic nature of this star, in agreement with Antonello et al. (1986). Under the assumption of monoperiodicity of β Cas, the classical O-C method can easily be applied. Nine times of maxima were obtained for the four nights by using the method described in Rodriguez et al. (1990), where each light maximum has been derived as an average over the four uvby bands. When the O-C method was applied, the least squares fit converged to a linear ephemeris with the following elements: To=2445568.d5097 (±0.d0007) and Po=0.d10091 (±0.d00002). This linear ephemeris satisfactorily reproduces our data of β Cas.

Background Medicines reconciliation in healthcare transitions may help prevent adverse drug events and improve patient safety. Purpose To describe and review the system for medicines reconciliation in order to improve drug treatment in elderly patients, and to evaluate the results. Materials and methods Descriptive study conducted November 2012–March 2013 on elderly patients with polypharmacy. Patients were selected through the billing system who were prescribed medicines every day by the internal medicine service while admitted. Stage 1-Detection: review of individual histories (emergency, outpatient, primary care etc.), structured interview with the patient and/or caregiver, full treatment review (self-medication, medicinal herbs, etc.). Treatment at home and in hospital was compared and discrepancies were detected. Stage 2-Evaluation: internists were contacted with a report prepared by the Pharmacy Department, stating the usual treatment, discrepancies and making recommendations to review potentially inappropriate medicines (PIMs). Stage 3-Resolution: pharmacotherapeutic plan updated at discharge and the family doctor telephoned to communicate the availability of the report. Stage 4: Definition of indicators to monitor the implementation of the program: % coverage of stages. Process indicators to assess safety improvement: % patients with medicines discrepancies and PIMs reported at admission, % patients with unresolved PIMs at discharge. Results During the study period 85 patients were reviewed with a mean age of 79.67 years (SD: 6.58). Indicators of implementation of the system: Stage 1 and 2: 100%. Stage 3: 49%. Process indicators: % Patients with discrepancies at admission: 90.6% prescribed unnecessary drugs: 39% not prescribed necessary drugs: 34% different dose, route, frequency (24%). % Patients with PIMs at admission: 72% long-acting benzodiazepines (24%) anti-inflammatory drugs (10%) amiodarone (7%) doxazosin (5%) aspirin (antiplatelet) (4%) tricyclic antidepressants (3%) % Patients with unresolved PIMs at discharge: 6% Conclusions The usefulness of the new system was demonstrated, in terms of resolution of discrepancies at admission, medicines were updated and PIMs decreased in the transition between hospital and primary care. No conflict of interest.

Numerical simulations are presented, which show that color information, as supplied by the exoplanetary camera of COROT, can be relevant to discriminate among several spherical degrees ` of the non-radial oscillations of δ Scuti stars. Introduction Multiperiodic δ Scuti stars show power spectra indicating that they pulsate in a mixing of radial and non-radial modes. Whereas period ratios can be used as an indication of the radial order n for radial modes they are not useful for the non-radial ones. Rotation and evolution –the so called “avoided crossing” phenomenon– complicate even more any mode identification. Spectroscopy – through line profile variations– and photometry –through the use of amplitude ratios and phase differences of different colors– have been widely utilized as techniques for mode identification. Here we will focus on the capability of the explanetary camera in COROT to supply color information which can be relevant for mode identification. Numerical simulations In front of the exoplanetary camera a bi-prism device will supply colored spotted images which will give three colors. These colors will depend on the spectral type of the considered star and on the position over the CCD plane. The full spot will be divided into three parts called “blue”, “green” and “red”, containing 20%, 20% and 60% respectively of the total flux. R. Garrido et al. 49 Figure 1: Amplitude ratio vs phase differences between “blue” and “green” bands of the exoplanetary camera of COROT for a model atmosphere of T = 7500 K, log g = 4.0 and periods close to a pulsation cosntant of Q = 0.035d. Regions for every ` value contain predictions for phase lags between 90 and 135 degrees and values of R between 0.25 and 1.00. The Kurucz model atmospheres have been improved in the way explained in detail in Heiter et al. (2002), basically by a better treatment of the convection and a larger number of shells in order to obtain good derivatives with respect to temperature and gravity. The linearised formula given by Watson (1988) has been used to compute the diagrams shown in Figure 1 and 2. Regions for different ` have been evaluated for an improved model atmosphere of T = 7500 K, log g = 4, Pop I and a period region around the fundamental radial mode –pulsation constant Q = 0.035 d– following the paper by Garrido et al. (1990). Basically the predictions are based on calculations assuming a phase lag –angle between temperature and radius variations– between 90 and 135 degrees and an R value –a parameter measuring the non-adiabaticity of the atmosphere– between 0.25 and 1.00. From these figures we can see a clear separation for high ` orders, giving very different regions in the amplitude ratio vs phase differences plane. For the lowest ` orders this separation is less evident but we expect that the accuracy at which COROT will supply light curves allows a precision for amplitudes and 50 Mode identification using the exoplanetary camera Figure 2: Same as figure 1 but for the central region. phases sufficient to discriminate among several ` orders and hence to help doing asteroseismology of these stars. References Garrido, R., Garcia-Lobo, E., Rodriguez, E. 1990, A&A 234, 262 Heiter, H., et al. 2002, in preparation Watson, R. D. 1988, Ap&SS 140, 255

We report photometric observations made at the Observatorio de Sierra Nevada of the secondary targets in the input catalogue of COROT. These observations consist of Stromgren {uvby- and Crawford {Hfl{ measurements of stars in Scenarios 1, 2 and 4. The cooler stars are being measured in the CaII H&K photometric system. We present here the present status of observations and reductions together with some preliminary results on the monitoring of photo- metric variability for some selected stars.

The fundus oculi is useful for observation of the interior of the eye and the retina. This study establishes a relationship between patients with established cerebral infarcts and the results observed in their fundi.A retrospective study of the clinical histories of 177 patients seen in the rehabilitation department over a period of one year.The patients were aged between 29 and 85 years. The majority were men; 101 patients (57.06%) had systolic-diastolic arterial hypertension. On study of the fundus oculi there was a predominance of alterations of the blood vessels of the retina due to vascular sclerosis (93.1%) but only 24.4% had frank alterations caused by arterial hypertension.We found a slight relation between arterial hypertension and the alterations observed in the fundus oculi of these patients.

Thrombotic thrombocytopenic purpura (TTP) or Moschovitz' syndrome is rare and is even rarer in childhood. Clinically, it is characterized by microangiopathic hemolytic anemia, thrombocytopenia, neurologic abnormalities, fever and renal dysfunction. The etiology is still unknown, although different factors such as large von Willebrand factor multimers and prostacyclin have been implicated. The acute form is more frequent, and in most cases the course is fulminant if treatment is not initiated. Laboratory data typically reveal hemolytic anemia, with schistocytes on the peripheral smear, diminished serum haptoglobin, and thrombocytopenia.We present the clinical cases of two children, aged 4 and 7 respectively, with TTP, but with different evolution and treatment. Evolution was favorable in both patients. The first child recovered spontaneously. In the second plasmapheresis was required and produced remission of all the symptomatology. Normality has been maintained for 36 and 24 months respectively, and the children have presented no clinico-biological alterations.

To determine the complaints leading adolescents to a third level emergency department, as well as the distinguishing features between the different groups of complaints.Retrospective study of the emergency department reports of 170 adolescents selected from the 1,172 adolescents who visited the Hospital Sant Joan de Déu pediatric emergency department in May 1997. We excluded 517 patients with trauma. Statistical analysis was carried out with the chi-square test for qualitative variables and analysis of variance for quantitative variables; differences were accepted as significant at p,0.05.Eighty-nine patients were female and 81 were male. Median age was 13.8 years. The most frequent discharge diagnoses were abdomen pain in 26 patients, viral illness in 15 and depression-anxiety in 14. Complementary investigations were carried out in 60 patients. One hundred forty-one patients were discharged. Of the 26 patients with psychiatric disorders, 18 were girls and 8 were boys. The proportion of girls was also higher among patients with abdominal and neurological symptoms, although not among patients with organic disorders (p50.03). Most of the patients with psychiatric antecedents were diagnosed with a psychiatric disorder. Ten (11.8%) of the 85 patients with organic complaints were admitted to hospital compared with 13(50%) of the 26 patients with psychiatric disorders (p,0.001).Adolescents visit emergency departments for a variety of complains. The proportion of psychiatric disorders and non-specific symptoms is high.

Hydrolysis of membrane phospholipids of spinal cord neurons is one of the first events initiated in spinal cord trauma. In this process, free fatty acids, and in particular arachidonic acid, are released. Exposure of spinal cord neurons to free arachidonic acid can compromise cell survival and initiate apoptotic cell death. In order to determine potential mechanisms of apoptosis induced by arachidonic acid, activation of caspases -3, -8, and -9, as well as the release of cytochrome c into the cytoplasm were measured in cultured spinal cord neurons exposed to 10 microM of this fatty acid. In addition, because nicotine can exert a variety of neuroprotective effects, we hypothesized that it can prevent arachidonic acid induced apoptosis of spinal cord neurons. To study this hypothesis, spinal cord neurons were pretreated with nicotine (10 microM for 2 h) before arachidonic acid exposure and caspase activation as well as markers of apoptotic cell death were studied. Treatment of spinal cord neurons with arachidonic acid for up to 24 h significantly increased cytoplasmic levels of cytochrome c, induced caspase activation and induced DNA laddering, a hallmark of apoptotic cell death. Nicotine pretreatment markedly attenuated all these effects. In addition, antagonist studies suggest that the alpha7 nicotinic receptor is primarily responsible for these anti-apoptotic effects of nicotine. These results indicate that nicotine can exert potent neuroprotective effects by inhibiting arachidonic acid induced apoptotic cascades of spinal cord neurons.

Voluntary intoxication as form of attempted suicide is currently a significant problem among the teenage population. Suicide attempt is the most frequent psychiatric emergency in adolescents. We present our 2-year experience of voluntary intoxication in a pediatric population.Retrospective and descriptive study of patients admitted because of voluntary intoxication in our center from January 1996 to December 1997. We analyzed age, sex, approximate time of intoxication, toxic habit antecedents, psychiatric evaluations or previous intoxications, type of toxic substance and method of obtaining it, symptomatology on arrival at the emergency department, therapeutic attitude and most common complementary examinations, and days of hospital stay.Forty-six patients with voluntary intoxication were admitted during the study period. The mean age was 15.6 years; 40 patients (87%) were female. Twenty-eight patients (60.9%) had previously been evaluated in a psychiatric department. The toxic substance used was of pharmacological origin, and in 38 patients (82.6%) it was obtained from the home first-aid kit. In 22 patients (47.8%) intoxication was due to multiple drugs. Six patients (13%) required admission to the pediatric intensive care unit. Mean duration of admission was 3 days.Voluntary intoxication as a form of attempted suicide is a significant problem among the teenage population, especially among teenage girls. The best preventive measure would be identification of the at-risk population, which consists mainly of teenage girls with depression, eating disorders, or previous suicide attempts.

Multicolor photometric observations of a planetary transit in the system HD 209458 are analyzed. The observations, made in the Stromgren photometric system, allowed a recalculation of the basic physical properties of the star-planet system. This includes derivation of linear limb-darkening values of HD 209458, which is the first time that a limb-darkening sequence has observationally been determined for a star other than the Sun. As the derived physical properties depend on assumptions that are currently known with limited precision only, scaling relations between derived parameters and assumptions are given. The observed limb-darkening is in good agreement with theoretical predictions from evolutionary stellar models combined with ATLAS model atmospheres, verifying these models for the temperature (Teff ~ 6000K), surface gravity (log g ~ 4.3) and mass (~ 1.2 Msol) of HD 209458., Comment: 16 pages, 8 figures, uses elsart.cls, accepted for New Astronomy

This paper concentrates on progress made in fault detection using the Fuzzy Inductive Reasoning (FIR) methodology. The so-called envelope approach is presented and compared with previous research efforts published by the same group in SIMULATION in 1989 and 1994. The comparison is achieved simulating faults in a B-747 commercial aircraft, the same example that had been used in the previous publications. The previously used crisp detection has been replaced by a new approach, based on the computation of an acceptability interval for each predicted variable. The paper demonstrates the improved capabilities of the new approach to detect faults earlier and in a more reliable manner., This work was supported by the project 'Seguridad de funcionamiento en sistemas dinámicos complejos' (J-00289).

Many studies have suggested that caring for patients with dementia may be associated with increased burden, particularly when subjects present with prominent behavioural problems. The present work aimed to review studies appearing on MedLine between 1990 and January 1998 that included the following keywords: 'burden or impact or cost' and 'dementia or Alzheimer's disease' and 'carer or caregiver or caregiving or family'. Only fourteen of the studies retrieved fulfilled the entry criteria for this review: crossectional or longitudinal studies looking at the association between behavioural problems in patients with dementia and burden of carers. All studies indicated that behavioural disturbances are an important cause of burden, although there was little consistency on the definition of 'behavioural disturbances'. As a consequence, it is still unclear which behavioural symptoms are more closely associated with increased burden of care. Future research in the area should aim to clarify these issues and develop management strategies to decrease burden on carers of patients with dementia.