Orexin A in cortical cultures: expression and effect on synaptogenesis during development

Orexin-A (OXA) is an excitatory hypothalamic neurotransmitter and ligand for Orexin Receptor-1 (OR1), isolated from a small group of hypothalamic neurons. OXA orchestrates different brain functions, and at the cognitive level some of the effects of insufficiency of OXA are well-known, for example in Parkinson’s disease. It is widely assumed that deteriorated cognitive processes are related to impaired network connectivity. However, little is known about the effects of OXA in network connectivity and synaptogenesis. Therefore, to obtain insight into this problem we designed experiments with two groups of networks of dissociated cortical neurons: one group incubated in a plain medium and another chronically treated with OXA. After one, two, three or four weeks in vitro we applied immunocytochemistry for detection of OXA, OR1 and synaptic marker synaptophysin. Shortly after plating, 91±8% of the neurons cultivated in a plain medium expressed OXA-immunoreactivity, which does normally not occur in vivo indicating that neurons may change their phenotype under non-natural culture conditions to develop synaptically coupled networks. The fraction of orexinergic neurons decreased to 33±21% after 4 weeks in vitro. OXA expression was highest in the first week of network formation, the period of maximum synaptogenesis, and then decreased and stabilized in the weeks thereafter. Our hypothesis that OXA plays a role in the network development as a synaptogenic factor was supported by higher levels, earlier onset, and sustained increase of synaptophysin-expression in experiments with chronic OXA application to the culture medium

Identication of linear slow sausage waves in magnetic pores

The analysis of an 11-hour series of high resolution white light observations of a large pore in the sunspot group NOAA 7519, observed on 5 June 1993 with the Swedish Vacuum Solar Telescope at La Palma on Canary Islands, has been recently described by Dorotovič et al. (2002). Special attention was paid to the evolution of a filamentary region attached to the pore, to horizontal motions around the pore, and to small-scale morphological changes. One of the results, relevant to out work here, was the determination of temporal area evolution of the studied pore where the area itself showed a linear trend of decrease with time at an average rate of −0.23 Mm2h−1 during the entire observing period. Analysing the time series of the are of the pore, there is strong evidence that coupling between the solar interior and magnetic atmosphere can occur at various scales and that the referred decrease of the area may be connected with a decrease of the magnetic field strength according to the magnetic field-to-size relation. Periods of global acoustic, e.g. p-mode, driven waves are usually in the range of 5–10 minutes, and are favourite candidates for the coupling of interior oscillations with atmospheric dynamics. However, by assuming that magneto-acoustic gravity waves may be there too, and may act as drivers, the observed periodicities (frequencies) are expected to be much longer (smaller), falling well within the mMHz domain. In this work we determine typical periods of such range in the area evolution of the pore using wavelet analysis. The resulted periods are in the range of 20–70 minutes, suggesting that periodic elements of the temporal evolution of the area of this studied pore could be linked to, and considered as, observational evidence of linear low-frequency slow sausage (magneto-acoustic gravity) waves in magnetic pores. This would give us further evidence on the coupling of global solar oscillations to the overlaying magnetic atmosphere

Kosten en effecten van esomeprazol in de behandeling van reflux ziekte

Doel. Het bepalen van de kosten-effectiviteit van esomeprazol (Nexium(r)) ten opzichte van alle andere in Nederland geregistreerde protonpomp remmers in de behandeling van reflux ziekte. Voor de effectiviteit vormt het hebben van voldoende controle over de symptomen het uitgangspunt. Perspectief. De studie is uitgevoerd zowel vanuit het perspectief van de verzekeraars als vanuit het maatschappelijk perspectief. Methoden. Gegevens met betrekking tot effectiviteit zijn afgeleid uit een systematische analyse van de literatuur. Gegevens omtrent zorgconsumptie zijn afkomstig uit interviews met huisartsen en gastro-enterologen. Een model is ontwikkeld, dat de gegevens over effectiviteit en kosten van behandeling bijeen brengt. De structuur van het model is vervolgens bediscussieerd met een panel van deskundigen. Tenslotte zijn de berekeningen uitgevoerd met het aangepaste model. Resultaten. Behandeling met esomeprazol 40 mg is dominant ten opzichte van de andere protonpomp remmers: 96,4% van de patiënten heeft na 8 weken voldoende controle over de klachten, tegen totale kosten van EUR 89 (maatschappelijk;m) / EUR 83 (verzekeraar;v). Na esomeprazol 40 mg is omeprazol 40 mg het meest effectief (95,2%), gevolgd door esomeprazol 20 mg (94%)

Cognitive functioning in meningioma patients:A systematic review

This systematic review evaluates relevant findings and methodologic aspects of studies on cognitive functioning in meningioma patients prior to and/or following surgery with or without adjuvant radiotherapy. PubMed and Web of Science electronic databases were searched until December 2015. From 1012 initially identified articles, 11 met the inclusion criteria for this review. Multiple methodological limitations were identified which include the lack of pre-treatment assessments, variations in the number and types of neuropsychological tests used, the normative data used to identify patients with cognitive deficits, and the variety of definitions for cognitive impairment. Study results suggest that most of meningioma patients are faced with cognitive deficits in several cognitive domains prior to surgery. Following surgery, most of these patients seem to improve in cognitive functioning. However, they still have impairments in a wide range of cognitive functions compared to healthy controls. Suggestions are given for future research. Adequate diagnosis and treatment of cognitive deficits may ultimately lead to improved outcome and quality of life in meningioma patients

Time-dependent changes in ghrelin-immunoreactivity in dissociated neuronal cultures of the newborn rat neocortex

Ghrelin is a hormone, initially described as a gastric peptide stimulating appetite and growth hormone secretion, which also has an important role in the regulation of many other processes, including higher brain functions. Ghrelin has been described in situ in different parts of the brain, but so far there has been no data about its expression in cell cultures. Therefore, we aimed in this study to investigate the levels of ghrelin in dissociated cortical neurons at various times in culture. We applied the ABC immunocytochemical method for the detection of ghrelin in one-day-, one-week-, and two-week-old cultures. Our results clearly show that at the early stages after plating the cultures 86.2% (± 8.93) of the neurons are ghrelin-positive and their number decreases during the culturing period. As ghrelin is present in the majority of cultured newborn neurons, when the neuronal differentiation and network formation take place, it may also influence the early synaptic formation and cell-to-cell interactions, which are both very important for network functions like learning and memory

HST/FOS Eclipse Observations of the Nova-like Cataclysmic Variable UX Ursae Majoris

[abridged abstract] We present and analyze Hubble Space Telescope observations of the eclipsing nova-like cataclysmic variable UX UMa obtained with the Faint Object Spectrograph. Two eclipses each were observed with the G160L grating (covering the ultraviolet waveband) in August of 1994 and with the PRISM (covering the near-ultraviolet to near-infrared) in November of the same year. The system was 50% brighter in November than in August, which, if due to a change in the accretion rate, indicates a fairly substantial increase in Mdot_acc by >~ 50%. Model disk spectra constructed as ensembles of stellar atmospheres provide poor descriptions of the observed post-eclipse spectra, despite the fact that UX UMa's light should be dominated by the disk at this time. Suitably scaled single temperature model stellar atmospheres with T_eff = 12,500-14,500 K actually provide a better match to both the ultraviolet and optical post-eclipse spectra. Evidently, great care must be taken in attempts to derive accretion rates from comparisons of disk models to observations. One way to reconcile disk models with the observed post-eclipse spectra is to postulate the presence of a significant amount of optically thin material in the system. Such an optically thin component might be associated with the transition region (``chromosphere'') between the disk photosphere and the fast wind from the system, whose presence has been suggested by Knigge & Drew (1997).Comment: 35 pages, including 12 figures; to appear in the ApJ (Vol. 499

Modeling Eclipses in the Classical Nova V Persei: The Role of the Accretion Disk Rim

Multicolor (BVRI) light curves of the eclipsing classical nova V Per are presented, and a total of twelve new eclipse timings are measured for the system. When combined with previous eclipse timings from the literature, these timings yield a revised ephemeris for the times of mid-eclipse given by HJD = 2,447,442.8260(1) + 0.107123474(3) E. The eclipse profiles are analyzed with a parameter-fitting model that assumes four sources of luminosity: a white dwarf primary star, a main-sequence secondary star, a flared accretion disk with a rim, and a bright spot at the intersection of the mass-transfer stream and the disk periphery. A matrix of model solutions are computed, covering an extensive range of plausible parameter values. The solution matrix is then explored to determine the optimum values for the fitting parameters and their associated errors. For models that treat the accretion disk as a flat structure without a rim, optimum fits require that the disk have a flat temperature profile. Although models with a truncated inner disk (R_in >> R_wd) result in a steeper temperature profile, steady-state models with a temperature profile characterized by T(r) \propto r^{-3/4} are found only for models with a significant disk rim. A comparison of the observed brightness and color at mid-eclipse with the photometric properties of the best-fitting model suggests that V Per lies at a distance of ~ 1 kpc.Comment: Accepted for publication in The Astrophysical Journal. Thirty-nine pages, including 9 figures. V2 - updated to include additional references and related discussion to previous work overlooked in the original version, and to correct a typo in the ephemeris given in the abstract. V3 - Minor typos corrected. The paper is scheduled for the 20 June 2006 issue of the ApJ. V4 - An error in equation (9) has been corrected. The results presented in the paper were not affected, as all computations were made using the correct formulation of this equatio

Formations of monoids, congruences, and formal languages

The main goal in this paper is to use a dual equivalence in automata theory started in [25] and developed in [3] to prove a general version of the Eilenberg-type theorem presented in [4]. Our principal results confirm the existence of a bijective correspondence between three concepts; formations of monoids, formations of languages and formations of congruences. The result does not require finiteness on monoids, nor regularity on languages nor finite index conditions on congruences. We relate our work to other results in the field and we include applications to non-r-disjunctive languages, Reiterman's equational description of pseudovarieties and varieties of monoid