Bipolar

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Bipolar

  • bipolar affective disorder
  • bipolar cell
  • bipolar depressed patient
  • bipolar depression
  • bipolar disorder
  • bipolar disorder patient
  • bipolar disorders
  • bipolar electrode
  • bipolar electrogram
  • bipolar group
  • bipolar i
  • bipolar i disorder
  • bipolar i mania
  • bipolar i patient
  • bipolar ii
  • bipolar ii depression
  • bipolar ii disorder
  • bipolar illness
  • bipolar lead
  • bipolar mania
  • bipolar patient
  • bipolar spectrum
  • bipolar spectrum disorders
  • bipolar spindle
  • bipolar subject
  • bipolar surface electrode
  • bipolar transistor

  • Selected Abstracts


    Bipolar, anastral spindle development in artificially activated sea urchin eggs

    DEVELOPMENTAL DYNAMICS, Issue 5 2008
    John H. Henson
    Abstract The mitotic apparatus of the early sea urchin embryo is the archetype example of a centrosome-dominated, large aster spindle organized by means of the centriole of the fertilizing sperm. In this study, we tested the hypothesis that artificially activated sea urchin eggs possess the capacity to assemble the anastral, bipolar spindles present in many acentrosomal systems. Control fertilized Lytechinus pictus embryos and ammonia-activated eggs were immunolabeled for tubulin, centrosomal material, the spindle pole structuring protein NuMA and the mitotic kinesins MKLP1/Kinesin-6, Eg5/Kinesin-5, and KinI/Kinesin-13. Confocal imaging showed that a subset of ammonia-activated eggs contained bipolar "mini-spindles" that were anastral; displayed metaphase and anaphase-like stages; labeled for centrosomal material, NuMA, and the three mitotic kinesins; and were observed in living eggs using polarization optics. These results suggest that spindle structural and motor proteins have the ability to organize bipolar, anastral spindles in sea urchin eggs activated in the absence of the paternal centriole. Developmental Dynamics 237:1348-1358, 2008. © 2008 Wiley-Liss, Inc. [source]


    Modelling and design considerations on CML gates under high-current effects

    INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 6 2005
    M. Alioto
    Abstract In this paper, the effect of the transit time degradation of bipolar transistors on the power-delay trade-off in CML gates and their design is dealt with. A delay model which accounts for the transit time increase due to the high bias current values used in high-speed applications is derived by generalizing an approach previously proposed by the same authors (IEEE Trans. CAD 1999; 18(9):1369,1375; Model and Design of Bipolar and MOS Current,Mode Logic (CML, ECL and SCL Digital Circuits), Kluwer Academic Publisher: Dordrecht, 2005). The resulting closed-form delay expression is achieved by properly simplifying the SPICE model, and has an explicit dependence on the bias current which determines the power consumption of CML gates. Accordingly, the delay model is used to gain insight into the power-delay trade-off by considering the effect of the transit time degradation in high-speed designs. In particular, the cases where such effects can be neglected are identified, to better understand how the transit time degradation affects the performance of CML gates for current bipolar technologies. The proposed model has a simple and compact expression, thus it turns out to be suitable for pencil-and-paper evaluations, as well as fast timing analysis. Simulations of CML circuits with a 20-GHz bipolar process show that the model has a very good accuracy in a wide range of current and loading conditions. Copyright © 2005 John Wiley & Sons, Ltd. [source]


    Ultrastructure of the tentacle nerve plexus and putative neural pathways in sea anemones

    INVERTEBRATE BIOLOGY, Issue 3 2002
    Jane A. Westfall
    Abstract. Neurons of sea anemone tentacles receive stimuli via sensory cells and process and transmit information via a plexus of nerve fibers. The nerve plexus is best revealed by scanning electron microscopy of epidermal peels of the tentacles. The nerve plexus lies above the epidermal muscular layer where it appears as numerous parallel longitudinal and short interconnected nerve fibers in Calliactis parasitica. Bipolar and multipolar neurons are present and neurites form interneuronal and neuromuscular synaptic contacts. Transmission electron microscopy of cross sections of tentacles of small animals, both C. parasitica and Aiptasia pallida, reveals bundles of 50,100 nerve fibers lying above groups of longitudinal muscle fibers separated by intrusions of mesoglea. Smaller groups of 10,50 slender nerve fibers are oriented at right angles to the circular muscle formed by the bases of the digestive cells. The unmyelinated nerve fibers lack any glial wrapping, although some bundles of epidermal fibers are partially enveloped by cytoplasmic extensions of the muscle cells; small gastrodermal nerve bundles lie between digestive epithelial cells above their basal myonemes. A hypothetical model for sensory input and motor output in the epidermal and gastrodermal nerve plexuses of sea anemones is proposed. [source]


    Randomized Comparison of Bipolar versus Unipolar Plus Bipolar Recordings During Segmental Ostial Ablation of Pulmonary Veins

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2002
    HIROSHI TADA M.D.
    Unipolar vs Bipolar Electrograms.Introduction: Segmental ostial ablation to isolate pulmonary veins is guided by pulmonary vein potentials. The aim of this prospective randomized study was to compare the utility of unipolar plus bipolar electrograms versus only bipolar electrograms as a guide for segmental ablation to isolate the pulmonary veins in patients with atrial fibrillation. Methods and Results: Isolation of the left superior, right superior, and left inferior pulmonary veins was attempted in 44 patients (35 men and 9 women; mean age 54 ± 10 years) with paroxysmal atrial fibrillation. A decapolar Lasso catheter was positioned in the pulmonary veins, near the ostium, and a conventional ablation catheter was used for segmental ablation aimed at elimination of all pulmonary vein potentials. One hundred fourteen pulmonary veins were randomly assigned for ostial ablation guided by either bipolar or unipolar plus bipolar recordings. Electrical isolation was achieved in 51 (96%) of 53 pulmonary veins randomized to the bipolar approach, and 57 (93%) of 61 pulmonary veins randomized to the unipolar plus bipolar approach (P = 0.7). In the unipolar plus bipolar group, the total duration of radiofrequency energy needed to achieve isolation, 5.5 ± 2.8 minutes/vein, was significant shorter than in the bipolar group, 7.6 ± 4.1 minutes/vein (P < 0.01). Mean procedure and fluoroscopy durations per vein were 19% to 28% shorter in the unipolar plus bipolar group. Conclusion: Segmental ostial ablation to isolate the pulmonary veins can be achieved more efficiently and with less radiofrequency energy when guided by both unipolar and bipolar recordings than by bipolar recordings alone. [source]


    Distribution of Corticotropin-Releasing Factor Binding Protein-Immunoreactivity in the Rat Hypothalamus: Association With Corticotropin-Releasing Factor-, Urocortin 1- and Vimentin-Immunoreactive Fibres

    JOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2005
    B. A. Henry
    Abstract Corticotropin-releasing factor binding protein (CRF-BP) is a 37-kDa protein with high affinity binding sites for both corticotropin-releasing factor (CRF) and urocortin 1. Previous studies have examined the distribution of CRF-BP mRNA and peptide within the central nervous system. Due to the predominant cortical localisation, very little is known about CRF-BP in subcortical structures including the hypothalamus. The present study employed immunohistochemistry to characterise the distribution of CRF-BP-like-immunoreactive (-ir) cells and fibres in the rat hypothalamus. Bipolar and multipolar CRF-BP-ir neurones were scattered throughout the rostro-caudal extent of the hypothalamus. Distinct clusters of CRF-BP-ir neurones were identified in the anterior and posterior parvocellular and dorsal cap subdivisions of the paraventricular nucleus (PVN), as well as in the dorsal hypothalamic area, dorsomedial hypothalamic nucleus (DMN), ventral premammillary nucleus and zona incerta. CRF-BP-ir fibres extending from the third ventricle were found in the mediobasal hypothalamus and within the arcuate nucleus-median eminence region. Double immunostaining together with confocal microscopy demonstrated that the CRF-BP-immunostained fibres within the mediobasal hypothalamus coincided with vimentin immunostaining indicating that CRF-BP-ir is present within tanycytes. To define the relationship between CRF-BP-ir cells and endogenous ligands for CRF-BP, double immunohistochemistry was performed to examine possible sites within the hypothalamus where CRF- or urocortin 1-ir fibres innervate regions that contain CRF-BP-ir cell bodies. CRF-BP-ir cell bodies typically coincided with dense CRF-ir, but not urocortin 1-ir fibre innervation. CRF-ir fibre innervation was moderate to high within the anterior and posterior parvocellular subdivisions of the PVN, the dorsal cap of the PVN, DMN and the zona incerta; all regions that contained CRF-BP-ir cell populations. These studies demonstrate that, within the hypothalamus, CRF-BP-ir cells and fibres are concentrated within a circuitry known to be involved in mediating neuroendocrine and autonomic responses to stress. [source]


    Plant traits enabling survival in Mediterranean badlands in northeastern Spain suffering from soil erosion

    JOURNAL OF VEGETATION SCIENCE, Issue 4 2008
    Joaquín Guerrero-Campo
    Abstract Question: This study analysed the effect of severe soil erosion on species composition of plant communities by favouring species showing certain growth forms, root-sprouting and clonal growth abilities. Location: The study area was located between the middle Ebro Valley and the Pre-Pyrenees (northeastern Spain). Methods: Root-sprouting and shoot-rooting abilities, clonal reproduction and growth form were assessed for the 123 most common plant species from eroded lands in the study area. We obtained 260 vegetation relevés in three different substrata (gypsum outcrops, Miocene clays and Eocene marls) on areas with different degrees of soil erosion. The frequency of every plant trait in each relevé was estimated according to species presence. The effect of soil erosion on the frequency of plant attributes was assessed by correlation analyses. Results: Bipolar, non-clonal plants and annual species decreased their frequency with increasing soil erosion in the three substrata analyzed, whereas root-sprouters and woody plants (mostly sub-shrubs) increased their frequency in most of the substrata analysed. Conclusions: Woody sub-shrubs, root-sprouters and clonal species are favoured in eroded lands in NE Spain. Bipolar species and annual plants might not be plastic enough to survive the high stress and frequent disturbances prevailing in such eroded areas. [source]


    Bipolar disorder in older adults: a critical review

    BIPOLAR DISORDERS, Issue 5 2004
    Colin A Depp
    Objectives:, The goal of this article is to provide a comprehensive critical review of studies reporting the prevalence, features, age of onset, course, comorbidity, and neuropsychology of, as well as service utilization, in bipolar disorder in older age. Methods:, We searched the Medline, Pubmed, and PsycINFO databases using combinations of the keywords ,Bipolar', ,Manic/a', ,Manic Depression', ,Elderly', and ,Older'. We included English-language reports presenting quantitative data on the prevalence and/or any descriptive information about adults with bipolar disorder over age 50. Findings from similar studies were pooled when possible. A total of 61 studies met our broad criteria. Results:, Common methodological problems in the published studies included small sample sizes, retrospective chart review, lack of standardized measures, overemphasis on inpatients, and dearth of longitudinal data. Strong evidence indicates that bipolar disorder becomes less common with age, accounts for 8,10% of late life psychiatric admissions, is associated with neurologic factors in late-onset groups, and is a heterogeneous life-long illness. Weak or inconsistent evidence was found for a higher prevalence of mixed episodes in older adults, a lower treatment response, and the association with lower family history in late-onset groups. Minimal information is available on bipolar depression in late life. Conclusions:, Bipolar disorder in old age is a growing public health problem. Greater research on bipolar disorder in older people will assist in enhancing services to this group as well as inform research on bipolar disorder across the life span. [source]


    Single-layered microscale linear-gradient PDLC material for electro-optics

    CRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2009
    Y. G. Marinov
    Abstract We report on single-layered optical material of linear-gradient microscale polymer-dispersed liquid crystal (PDLC). E7/NOA65 composite films formed by pulsed UV laser photopolymerization-induced phase separation exhibit two morphology types, namely a bipolar and a hybrid alignment of liquid crystal droplets. The specific structural properties of the produced PDLC layers, such as the droplet shape uniformity and alignment, as well as the droplet size control through the film thickness, facilitate the efficient control on the electro-optical (EO) response, thus being of practical interest for EO device applications. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


    Mania associated with antidepressant treatment: comprehensive meta-analytic review

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010
    L. Tondo
    Tondo L, Vázquez G, Baldessarini RJ. Mania associated with antidepressant treatment: comprehensive meta-analytic review. Objective:, To review available data pertaining to risk of mania,hypomania among bipolar (BPD) and major depressive disorder (MDD) patients with vs. without exposure to antidepressant drugs (ADs) and consider effects of mood stabilizers. Method:, Computerized searching yielded 73 reports (109 trials, 114 521 adult patients); 35 were suitable for random effects meta-analysis, and multivariate-regression modeling included all available trials to test for effects of trial design, AD type, and mood-stabilizer use. Results:, The overall risk of mania with/without ADs averaged 12.5%/7.5%. The AD-associated mania was more frequent in BPD than MDD patients, but increased more in MDD cases. Tricyclic antidepressants were riskier than serotonin-reuptake inhibitors (SRIs); data for other types of ADs were inconclusive. Mood stabilizers had minor effects probably confounded by their preferential use in mania-prone patients. Conclusion:, Use of ADs in adults with BPD or MDD was highly prevalent and moderately increased the risk of mania overall, with little protection by mood stabilizers. [source]


    Electroconvulsive therapy is equally effective in unipolar and bipolar depression

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010
    S. Bailine
    Bailine S, Fink M, Knapp R, Petrides G, Husain MM, Rasmussen K, Sampson S, Mueller M, McClintock SM, Tobias KG, Kellner CH. Electroconvulsive therapy is equally effective in unipolar and bipolar depression. Objective:, To determine the relative efficacy of electroconvulsive therapy (ECT) in the treatment of bipolar (BP) and unipolar (UP) depressive illness and clarify its role in BP depression. Method:, Patients referred for ECT with both UP and BP depressions. [classified by Structured Clinical Interview for DSM (SCID-I) criteria for history of mania] were included in a multi-site collaborative, double-masked, randomized controlled trial of three electrode placements , right unilateral, bifrontal or bitemporal , in a permutated block randomization scheme. Results:, Of 220 patients, 170 patients (77.3%) were classified as UP and 50 (22.7%) as BP depression in the intent-to-treat sample. The remission and response rates and numbers of ECT for both groups were equivalent. Conclusion:, Both UP and BP depressions remit with ECT. Polarity is not a factor in the response rate. In this sample ECT did not precipitate mania in depressed patients. Treatment algorithms for UP and BP depression warrant re-evaluation. [source]


    Age at onset in 3014 Sardinian bipolar and major depressive disorder patients

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010
    L. Tondo
    Tondo L, Lepri B, Cruz N, Baldessarini RJ. Age at onset in 3014 Sardinian bipolar and major depressive disorder patients. Objective:, To test if onset age in major affective illnesses is younger in bipolar disorder (BPD) than unipolar-major depressive disorder (UP-MDD), and is a useful measure. Method:, We evaluated onset-age for DSM-IV-TR major illnesses in 3014 adults (18.5% BP-I, 12.5% BP-II, 69.0% UP-MDD; 64% women) at a mood-disorders center. Results:, Median and interquartile range (IQR) onset-age ranked: BP-I = 24 (19,32) < BP-II = 29 (20,40) < UP-MDD = 32 (23,47) years (P < 0.0001), and has remained stable since the 1970s. In BP-I patients, onset was latest for hypomania, and depression presented earlier than in BP-II or UP-MDD cases. Factors associated with younger onset included: i) being unmarried, ii) more education, iii) BPD-diagnosis, iv) family-history, v) being employed, vi) ever-suicidal, vii) substance-abuse and viii) ever-hospitalized. Onset-age distinguished BP-I from UP-MDD depressive onsets with weak sensitivity and specificity. Conclusion:, Onset age was younger among BPD than MDD patients, and very early onset may distinguish BPD vs. UP-MDD with depressive-onset. [source]


    Do the old psychostimulant drugs have a role in managing treatment-resistant depression?

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 4 2010
    G. Parker
    Parker G, Brotchie H. Do the old psychostimulant drugs have a role in managing treatment-resistant depression? Objective:, As the authors have observed clinical benefit from the psychostimulants methylphenidate and dexamphetamine for treating resistant melancholic and bipolar depression, those drugs were evaluated in a consecutively recruited sample of 50 such patients. Method:, Patients (27 bipolar, 23 unipolar) received either methylphenidate (n = 44) or dexamphetamine (n = 6), with 30 having it prescribed as an augmenting drug and 20 as monotherapy. At the final review, ranging from 6 weeks to 62 months (mean 57 weeks), 52% were still receiving their psychostimulant. Results:, Thirty-four per cent reported the psychostimulant as distinctly improving their depression, 30% reported some level of improvement and 36% reported no improvement and/or side-effects. For improvers, the modal dose of methylphenidate was 20 mg. Significant side-effects were reported by 18% (including one manic response), switching was rare and limited to the bipolar subjects, and most side-effects were minor. Any positive response occurred rapidly and loss of efficacy was rare. Testing of tricyclic levels in some patients suggested that stimulant drugs may raise tricyclic levels in those who are rapid metabolizers. Conclusion:, Although this study was not controlled, the high success rate in a diagnostically refined sample implies that the psychostimulants may be efficacious for patients with melancholic and bipolar depression who have failed to respond to orthodox antidepressant drugs. [source]


    White matter lesions in euthymic patients with bipolar disorder

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2009
    A. J. Lloyd
    Objective:, We aimed to quantify both load and regional distributions of hyperintensities on magnetic resonance imaging (MRI) in prospectively verified euthymic bipolar patients and matched controls. Method:, Cerebral hyperintensities on T2, proton density and fluid-attenuated inversion recovery (FLAIR) MRI were compared between 48 bipolar and 47 control subjects using semi-quantitative rating scales. Results:, Bipolar subjects had more severe frontal deep white matter lesions (DWML). Hyperintensity load was independent of age in bipolar patients but increased with age in controls. Global prevalence and severity of hyperintensities did not differ between groups. Exploratory analysis showed DWML in excess in the left hemisphere in bipolar subjects but not in controls. Conclusion:, Findings are consistent with clinical, particularly some neurocognitive, features of bipolar disorder and implicate fronto-subcortical circuits in its neurobiology. They more probably reflect a trait abnormality or illness scar rather than a mood state-dependent finding. Processes other than ageing and vascular factors may underlie their development. [source]


    Bipolar, anastral spindle development in artificially activated sea urchin eggs

    DEVELOPMENTAL DYNAMICS, Issue 5 2008
    John H. Henson
    Abstract The mitotic apparatus of the early sea urchin embryo is the archetype example of a centrosome-dominated, large aster spindle organized by means of the centriole of the fertilizing sperm. In this study, we tested the hypothesis that artificially activated sea urchin eggs possess the capacity to assemble the anastral, bipolar spindles present in many acentrosomal systems. Control fertilized Lytechinus pictus embryos and ammonia-activated eggs were immunolabeled for tubulin, centrosomal material, the spindle pole structuring protein NuMA and the mitotic kinesins MKLP1/Kinesin-6, Eg5/Kinesin-5, and KinI/Kinesin-13. Confocal imaging showed that a subset of ammonia-activated eggs contained bipolar "mini-spindles" that were anastral; displayed metaphase and anaphase-like stages; labeled for centrosomal material, NuMA, and the three mitotic kinesins; and were observed in living eggs using polarization optics. These results suggest that spindle structural and motor proteins have the ability to organize bipolar, anastral spindles in sea urchin eggs activated in the absence of the paternal centriole. Developmental Dynamics 237:1348-1358, 2008. © 2008 Wiley-Liss, Inc. [source]


    Proneural gene ash1 promotes amacrine cell production in the chick retina

    DEVELOPMENTAL NEUROBIOLOGY, Issue 2-3 2009
    Weiming Mao
    Abstract The diverse types of neurons and Müller glia in the vertebrate retina are believed to arise from common progenitor cells. To better understand how neural diversity is achieved during retinal neurogenesis, we examined the function of ash1, a proneural bHLH gene expressed in progenitor cells throughout retinal neurogenesis. Published studies using retinal explant culture derived from knockout mice concluded that ash1 is required for the production of late-born neurons, including bipolar cells. In this study, gain-of-function experiments were carried out in ovo in embryonic chick retina. In the developing chick retina, expression of ash1 temporally overlapped with, but spatially differed from, the expression of ngn2, also a proneural gene expressed in progenitor cells throughout retinal neurogenesis. Retrovirus-driven overexpression of ash1 in the developing chick retina decreased the progenitor population (BrdU+ or expressing ngn2), expanded the amacrine population (AP2,+ or Pax6+), and reduced bipolar (chx10 mRNA+) and Müller glial (vimentin+) populations. Photoreceptor deficiency occurred after the completion of neurogenesis. The number of ganglion cells, which are born first during retinal neurogenesis, remained unchanged. Similar overexpression of ngn2 did not produce discernible changes in retinal neurogenesis, nor in ash1 expression. These results suggest that ash1 promotes the production of amacrine cells and thus may participate in a regulatory network governing neural diversity in the chick retina. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source]


    Novel antipsychotics in bipolar and schizoaffective mania

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2004
    G. J. R. Mensink
    Objective:, Novel antipsychotics are increasingly used in the treatment of bipolar and schizoaffective mania. This paper presents an overview of the controlled studies in this field. Method:, Using cross-references, a computerized search was performed on MEDLINE and EMBASE psychiatry covering the period 1990,2002. Results:, Olanzapine and risperidone, added to mood stabilizers, and olanzapine as monotherapy enjoy the most evidential support in terms of efficacy and side-effect profile for their use in acute bipolar mania. The use of modern antipsychotics in bipolar prophylaxis and in both the short- and long-term treatment of schizomania has not been widely studied yet. Conclusion:, More controlled trials are still needed comparing modern antipsychotics as monotherapy and adjunctive to mood stabilizers with conventional antipsychotics, lithium, anticonvulsants and with each other in short-term and, especially, maintenance treatment of (schizo)mania. Partly based on controlled studies, olanzapine, risperidone and other modern antipsychotics could become preferable for these indications. [source]


    Dopamine transporter gene (DAT1) VNTR polymorphism in major psychiatric disorders: family-based association study in the Bulgarian population

    ACTA PSYCHIATRICA SCANDINAVICA, Issue 5 2002
    L. Georgieva
    Objective:,A 40-bp variable number tandem repeat in the 3,-UTR of dopamine transporter gene (DAT1) has been examined for association with major psychiatric disorders in several case,control studies. No significant results have been found. We used a new collection of parent,offspring trios to test for association with schizophrenia (SZ), bipolar 1 disorder (BPI) and schizoaffective (SA) disorder. Method:,We genotyped trios from Bulgarian origin where the proband had SZ (178 trios), BPI (77 trios) and SA (29 trios). Alleles ranging from 5 to 11 repeats were observed. The results were analysed with the extended TDT (ETDT). Results:,No preferential transmission of alleles was observed for any diagnostic group. The presence of allele DAT*10 was associated with the severity and frequency of auditory hallucinations, however, this result is not significant if corrected for multiple testing. Conclusion:,Our results are in agreement with previous reports of a lack of association between this polymorphism and major psychiatric disorders. [source]


    Antiepileptogenic and antiictogenic effects of retigabine under conditions of rapid kindling: An ontogenic study

    EPILEPSIA, Issue 10 2008
    Andréy Mazarati
    Summary Purpose:, To examine antiepileptogenic and antiictogenic potential of retigabine (RTG) under conditions of rapid kindling epileptogenesis during different stages of development. Methods:, The experiments were performed in postnatal day 14 (P14), P21, and P35 male Wistar rats. After stereotaxic implantation of hippocampal stimulating and recording electrodes, the effects of RTG on baseline afterdischarge (AD) properties were studied. Next, the animals underwent rapid kindling (sixty 10 s trains, bipolar 20 Hz square wave pulses delivered every 5 min). The progression of seizures (kindling acquisition), and responses to test stimulations after kindling (retention) were compared between RTG and vehicle-treated rats. Additionally, the effects of RTG on the severity of seizures in previously kindled animals were examined. Results:, When administered intraperitoneally in doses that induced only mild, or no motor deficits, RTG significantly dampened brain excitability, evident as the increase of AD threshold and shortening of AD duration. During kindling, RTG delayed the development of focal seizures in P14 rats, and prevented the occurrence of full limbic seizures at all three ages. At P14 and P21, but not at P35, pretreatment with RTG prevented the establishment of kindling-induced enhanced seizure susceptibility. Administration of RTG to kindled animals decreased the severity of seizures induced by test stimulation. The effect was most prominent at P14. Discussion:, RTG exerted both antiepileptogenic and antiictogenic effects under conditions of rapid kindling model. These effects were apparent during postneonatal, early childhood, and adolescent stages of development. [source]


    Plasma Concentrations of Risperidone and Olanzapine during Coadministration with Oxcarbazepine

    EPILEPSIA, Issue 5 2005
    Maria Rosaria Muscatello
    Summary:,Purpose: Oxcarbazepine (OZC) is a second-generation antiepileptic drug (AED) that also may be used as a mood stabilizer. Unlike carbamazepine (CBZ), which is an inducer of the cytochrome P-450 isoforms and may accelerate the elimination of several therapeutic agents, OXC seems to have only a modest inducing action. The aim of this investigation was to evaluate the effect of a treatment with OXC on plasma concentrations of the new antipsychotics risperidone and olanzapine. Methods: OXC, at a dosage of 900,1,200 mg/day, was administered for 5 consecutive weeks to 25 outpatients, 10 men and 15 women, aged 25 to 64 years, with bipolar or schizoaffective disorder. Twelve patients were stabilized on risperidone therapy (2,6 mg/day) and 13 on olanzapine (5,20 mg/day). Steady-state plasma concentrations of risperidone and its active metabolite 9-hydroxyrisperidone (9-OH-risperidone) and olanzapine were measured by high-pressure liquid chromatography (HPLC) before addition of OXC and after 5 weeks from the start of adjunctive treatment. Results: OXC caused only minimal and no significant changes in the mean plasma levels of risperidone (from 5.6 ± 3.6 ng/ml at baseline to 4.8 ± 2.6 ng/ml at week 5), 9-OH-risperidone (from 23.6 ± 7.5 to 24.7 ± 7.4 ng/ml), and olanzapine (from 26.5 ± 5.7 ng/ml at baseline to 27.8 ± 5.1 ng/ml). OXC coadministration with either risperidone or olanzapine was well tolerated. Conclusions: Our findings indicate that OXC does not affect the elimination of risperidone and olanzapine, thus confirming its weak inducing effect on hepatic drug-metabolizing enzymes. [source]


    Characterization and synaptic connectivity of melanopsin-containing ganglion cells in the primate retina

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2007
    Patricia R. Jusuf
    Abstract Melanopsin is a photopigment expressed in retinal ganglion cells, which are intrinsically photosensitive and are also involved in retinal circuits arising from rod and cone photoreceptors. This circuitry, however, is poorly understood. Here, we studied the morphology, distribution and synaptic input to melanopsin-containing ganglion cells in a New World monkey, the common marmoset (Callithrix jacchus). The dendrites of melanopsin-containing cells in marmoset stratify either close to the inner nuclear layer (outer stratifying), or close to the ganglion cell layer (inner stratifying). The dendritic fields of outer-stratifying cells tile the retina, with little overlap. However, the dendritic fields of outer-stratifying cells largely overlap with the dendritic fields of inner-stratifying cells. Thus, inner-stratifying and outer-stratifying cells may form functionally independent populations. The synaptic input to melanopsin-containing cells was determined using synaptic markers (antibodies to C-terminal binding protein 2, CtBP2, for presumed bipolar synapses, and antibodies to gephyrin for presumed amacrine synapses). Both outer-stratifying and inner-stratifying cells show colocalized immunoreactive puncta across their entire dendritic tree for both markers. The density of CtBP2 puncta on inner dendrites was about 50% higher than that on outer dendrites. The density of gephyrin puncta was comparable for outer and inner dendrites but higher than the density of CtBP2 puncta. The inner-stratifying cells may receive their input from a type of diffuse bipolar cell (DB6). Our results are consistent with the idea that both outer and inner melanopsin cells receive bipolar and amacrine input across their dendritic tree. [source]


    Glutamate enhances proliferation and neurogenesis in human neural progenitor cell cultures derived from the fetal cortex

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2006
    Masatoshi Suzuki
    Abstract Excitatory amino acids such as glutamate play important roles in the central nervous system. We previously demonstrated that a neurosteroid, dehydroepiandrosterone (DHEA), has powerful effects on the cell proliferation of human neural progenitor cells (hNPC) derived from the fetal cortex, and this effect is modulated through NMDA receptor signaling. Here, we show that glutamate can significantly increase the proliferation rates of hNPC. The increased proliferation could be blocked by specific NMDA receptor antagonists, but not other glutamate antagonists for kainate,AMPA or metabotropic receptors. The NR1 subunit of the NMDA receptor was detectable in elongated bipolar or unipolar cells with small cell bodies. These NR1-positive cells were colocalized with GFAP immunoreactivity. Detection of the phosphorylation of cAMP response element-binding protein (pCREB) revealed that a subset of NR1-positive hNPC could respond to glutamate. Furthermore, we hypothesized that glutamate treatment may affect mainly the hNPC with a radial morphology and found that glutamate as well as DHEA selectively affected elongated hNPC; these elongated cells may be a type of radial glial cell. Finally we asked whether the glutamate-responsive hNPC had an increased potential for neurogenesis and found that glutamate-treated hNPC produced significantly more neurons following differentiation. Together these data suggest that glutamate stimulates the division of human progenitor cells with neurogenic potential. [source]


    Patterns of calcium-binding proteins support parallel and hierarchical organization of human auditory areas

    EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003
    Oriana Chiry
    Abstract The human primary auditory cortex (AI) is surrounded by several other auditory areas, which can be identified by cyto-, myelo- and chemoarchitectonic criteria. We report here on the pattern of calcium-binding protein immunoreactivity within these areas. The supratemporal regions of four normal human brains (eight hemispheres) were processed histologically, and serial sections were stained for parvalbumin, calretinin or calbindin. Each calcium-binding protein yielded a specific pattern of labelling, which differed between auditory areas. In AI, defined as area TC [see C. von Economo and L. Horn (1930) Z. Ges. Neurol. Psychiatr.,130, 678,757], parvalbumin labelling was dark in layer IV; several parvalbumin-positive multipolar neurons were distributed in layers III and IV. Calbindin yielded dark labelling in layers I,III and V; it revealed numerous multipolar and pyramidal neurons in layers II and III. Calretinin labelling was lighter than that of parvalbumin or calbindin in AI; calretinin-positive bipolar and bitufted neurons were present in supragranular layers. In non-primary auditory areas, the intensity of labelling tended to become progressively lighter while moving away from AI, with qualitative differences between the cytoarchitectonically defined areas. In analogy to non-human primates, our results suggest differences in intrinsic organization between auditory areas that are compatible with parallel and hierarchical processing of auditory information. [source]


    Avoiding the effect of item wording by means of bipolar instead of unipolar items: An application to social optimism

    EUROPEAN JOURNAL OF PERSONALITY, Issue 2 2010
    Karl Schweizer
    Abstract Scales including positively and negatively worded items usually show an impaired degree of homogeneity. The transformation of unipolar positively and negatively worded items into bipolar items can avoid this disadvantageous effect. The precondition for this transformation is that each pair of items refers to the same topic. It is this topic that serves as the heading of the bipolar item. This scale construction method is demonstrated in the items of the social optimism scale (Schweizer & Schneider, 1997) that comprises unipolar items. The investigation of both the original and the transformed scales in a sample of 808 participants revealed equivalence and a high quality for both scales. Results of an additional sample confirmed the validity of both social optimism scales. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Liquid Crystal Emulsions as the Basis of Biological Sensors for the Optical Detection of Bacteria and Viruses

    ADVANCED FUNCTIONAL MATERIALS, Issue 14 2009
    Sri Sivakumar
    Abstract A versatile sensing method based on monodisperse liquid crystal (LC) emulsion droplets detects and distinguishes between different types of bacteria (Gram +ve and ,ve) and viruses (enveloped and non-enveloped). LCs of 4-cyano-4'-pentylbiphenyl transition from a bipolar to radial configuration when in contact with Gram ,ve bacteria (E. coli) and lipid-enveloped viruses (A/NWS/Tokyo/67). This transition is consistent with the transfer of lipid from the organisms to the interfaces of the micrometer-sized LC droplets. In contrast, a transition to the radial configuration is not observed in the presence of Gram +ve bacteria (Bacillus subtilis and Micrococcus luteus) and non-enveloped viruses (M13 helper phage). The LC droplets can detect small numbers of E. coli bacteria (1,5) and low concentrations (104,pfu mL,1) of A/NWS/Tokyo/67 virus. Monodisperse LC emulsions incubated with phosholipid liposomes (similar to the E. coli cell wall lipid) reveal that the orientational change is triggered at an area per lipid molecule of ,46,Å2 on an LC droplet (,1.6,×,108 lipid molecules per droplet). This approach represents a novel means to sense and differentiate between types of bacteria and viruses based on their cell-wall/envelope structure, paving the way for the development of a new class of LC microdroplet-based biological sensors. [source]


    Non-antagonistic relationship between mitogenic factors and cAMP in adult Schwann cell re-differentiation

    GLIA, Issue 9 2009
    Paula V. Monje
    Abstract The expression of myelination-associated genes (MGs) can be induced by cyclic adenosine monophosphate (cAMP) elevation in isolated Schwann cells (SCs). To further understand the effect of known SC mitogens in the regulation of SC differentiation, we studied the response of SCs isolated from adult nerves to combined cAMP, growth factors, including neuregulin, and serum. In adult SCs, the induction of MGs by cAMP coincided with the loss of genes expressed in non-myelin-forming SCs and with a change in cell morphology from a bipolar to an expanded epithelial-like shape. Prolonged treatment with high doses of cAMP-stimulating agents, as well as low cell density, was required for the induction of SC differentiation. Stimulation with serum, neuregulin alone, or other growth factors including PDGF, IGF and FGF, increased SC proliferation but did not induce the expression of MGs or the associated morphological change. Most importantly, when these factors were administered in combination with cAMP-stimulating agents, SC proliferation was synergistically increased without reducing the differentiating activity of cAMP. Even though the initiation of DNA synthesis and the induction of differentiation were mostly incompatible events in individual cells, SCs were able to differentiate under conditions that also supported active proliferation. Overall, the results indicate that in the absence of neurons, cAMP can trigger SC re-differentiation concurrently with, but independently of, growth factor signaling. © 2008 Wiley-Liss, Inc. [source]


    Simultaneous IR Material Recognition and Conductivity Mapping by Nanoscale Near-Field Microscopy,

    ADVANCED MATERIALS, Issue 17 2007
    J. Huber
    IR scattering-type near-field microscopy is applied to simultaneously map material composition and conduction properties in cross-sectional samples of industrial bipolar and metal-oxide- semiconductor devices with nanoscale spatial resolution. Within a single mid-IR image, all relevant materials such as metals, Si, Si3N4, and oxides can be identified by material-specific amplitude and phase contrasts. [source]


    Caudate volume measurement in older adults with bipolar disorder

    INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2004
    John L. Beyer
    Abstract Background Decreased caudate volumes have been noted in unipolar depressed subjects, especially in the elderly and those with cognitive impairment. No differences have been noted in initial studies of multi-aged bipolar subjects; however, this region has not been examined in older bipolar subjects. Methods We examined the caudate nuclei volumes of 36 older bipolar subjects (mean age 58) and 35 older controls (mean age 62) using logistic regression analyses to control for age and gender differences. Differences between late- and early-onset (age-of-onset before age 45) bipolar subjects were also examined, as well as the effect of length of illness. Results The right caudate was noted to be smaller in older bipolar subjects compared with older controls when controlled for sex and age (p,=,0.0448). No differences were noted in overall brain volume nor lateral ventricular volume between the bipolar and control subjects. Late-onset bipolar subjects had a decrease in brain volume (p,=,0.035) compared with early-onset bipolar subjects. Late-onset bipolar subjects had a decrease in the right (p,=,0.044) and total (p,=,0.04) caudate size compared with older controls. Conclusions Right caudate volume is decreased in older bipolar subjects compared to controls. Bipolar subjects with late-onset illness have significantly decreased right and total caudate volumes compared to controls. This is affected by neither the length of illness nor the age of onset. Late-onset bipolar subjects have decreased total brain volume compared with early-onset bipolar subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Bipolarity in bilattice logics

    INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 10 2008
    Sébastien Konieczny
    This paper is centered on a family of propositional multivalued logics, based on bilattices. The semantics of such logics relies on a set of "truth values," with two orderings that give the set a bilattice structure. Many interesting inference relations can be defined on these grounds, especially paraconsistent ones and/or nonmonotonic ones. The focus is laid on Belnap's fundamental bilattice logic FOUR, with four "epistemic truth values," which proves sufficient for the purpose of inference. We show how the bilattice can be associated with a second biordinal structure, which no longer is bilatticial but bipolar. We show how additional inference relations in the logic FOUR can be obtained by exploiting the two preorders associated with this structure. © 2008 Wiley Periodicals, Inc. [source]


    Meta-analyses of agreement between diagnoses made from clinical evaluations and standardized diagnostic interviews

    INTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 3 2009
    David C. Rettew
    Abstract Standardized diagnostic interviews (SDIs) have become de facto gold standards for clinical research. However, because clinical practitioners seldom use SDIs, it is essential to determine how well SDIs agree with clinical diagnoses. In meta-analyses of 38 articles published from 1995 to 2006 (N = 15,967 probands), mean kappas (z -transformed) between diagnoses from clinical evaluations versus SDIs were 0.27 for a broad category of all disorders, 0.29 for externalizing disorders, and 0.28 for internalizing disorders. Kappas for specific disorders ranged from 0.19 for generalized anxiety disorder to 0.86 for anorexia nervosa (median = 0.48). For diagnostic clusters (e.g. psychotic disorders), kappas ranged from 0.14 for affective disorders (including bipolar) to 0.70 for eating disorders (median = 0.43). Kappas were significantly higher for outpatients than inpatients and for children than adults. However, these effects were not significant in meta-regressions. Conclusions: Diagnostic agreement between SDIs and clinical evaluations varied widely by disorder and was low to moderate for most disorders. Thus, findings from SDIs may not fully apply to diagnoses based on clinical evaluations of the sort used in the published studies. Rather than implying that SDIs or clinical evaluations are inferior, characteristics of both may limit agreement and generalizability from SDI findings to clinical practice. Copyright © 2009 John Wiley & Sons, Ltd. [source]


    Adhesion of Staphylococcus aureus and Staphylococcus epidermidis to the Episkin® reconstructed epidermis model and to an inert 304 stainless steel substrate

    JOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2004
    G. Lerebour
    Abstract Aims:, The aim of this study was to evaluate the respective influence of the physicochemical interactions and the roughness involved in the first part of the biological substrate biocontamination. Methods and Results:, Therefore we compared the bioadhesion results obtained on the biological model substrate (Episkin®) and on a commonly employed inert substrate (AISI 304 stainless steel), frequently used either in dermatology or in development of medical devices. The two studied strains presented different characteristics, both physicochemical and microbiological. Staphylococcus epidermidis, a relatively hydrophobic bacteria capable of exchanging interactions which are principally of the van der Waals type, adhered more to 304 steel than to the surface of reconstituted skin. As for S. aureus, an essentially basic, hydrophilic bacteria, was more adherent to Episkin® (a bipolar, hydrophilic substrate) than to stainless steel (a unipolar, basic, hydrophilic substrate). Conclusions:, In the absence of electrostatic interactions, the adhesion of substrate-dependent bacteria to the surface of reconstituted skin was dependent upon the balance between ,LW, ,+ and ,,. Significance and Impact of the Study:, Consequently, so as to restrict microbial adhesion and reduce adhesive binding between micro-organisms and the surface of the skin, it would be preferable to render this substrate hydrophobic and apolar through the use of appropriate surface treatment. [source]