721 resultados para BIPOLAR LOCALIZATION
Resumo:
Bipolar affective disorder (BD) is a severe, recurrent and disabling disorder with devastating consequences for individuals, families and society. Although these hazards and costs provide a compelling rationale for development of early detection and early intervention strategies in BD, the development of at-risk criteria for first episode mania is still in an early stage of development. In this paper we review the literature with respect to the clinical, neuroantomical and neuropsychological data, which support this goal. We also describe our recently developed bipolar at-risk criteria (BAR). This criteria comprises the peak age range of the first onset of bipolar disorder, genetic risk, presenting with sub-threshold mania, cyclothymic features or depressive symptoms. An initial pilot evaluation of the BAR criteria in 22 subjects indicated conversion rates to proxies of first-episode mania of 23% within 265 days on average, and high specificity and sensitivity of the criteria. If prospective studies confirm the validity of the BAR criteria, then the criteria would have the potential to open up new avenues of research for indicated prevention in BD and might therefore offer opportunities to ameliorate the severity of, or even prevent BD.
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Cilengitide is a high-affinity cyclic pentapeptdic alphaV integrin antagonist previously reported to suppress angiogenesis by inducing anoikis of endothelial cells adhering through alphaVbeta3/alphaVbeta5 integrins. Angiogenic endothelial cells express multiple integrins, in particular those of the beta1 family, and little is known on the effect of cilengitide on endothelial cells expressing alphaVbeta3 but adhering through beta1 integrins. Through morphological, biochemical, pharmacological and functional approaches we investigated the effect of cilengitide on alphaVbeta3-expressing human umbilical vein endothelial cells (HUVEC) cultured on the beta1 ligands fibronectin and collagen I. We show that cilengitide activated cell surface alphaVbeta3, stimulated phosphorylation of FAK (Y(397) and Y(576/577)), Src (S(418)) and VE-cadherin (Y(658) and Y(731)), redistributed alphaVbeta3 at the cell periphery, caused disappearance of VE-cadherin from cellular junctions, increased the permeability of HUVEC monolayers and detached HUVEC adhering on low-density beta1 integrin ligands. Pharmacological inhibition of Src kinase activity fully prevented cilengitide-induced phosphorylation of Src, FAK and VE-cadherin, and redistribution of alphaVbeta3 and VE-cadherin and partially prevented increased permeability, but did not prevent HUVEC detachment from low-density matrices. Taken together, these observations reveal a previously unreported effect of cilengitide on endothelial cells namely its ability to elicit signaling events disrupting VE-cadherin localization at cellular contacts and to increase endothelial monolayer permeability. These effects are potentially relevant to the clinical use of cilengitide as anticancer agent.
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We present a combined shape and mechanical anisotropy evolution model for a two-phase inclusion-bearing rock subject to large deformation. A single elliptical inclusion embedded in a homogeneous but anisotropic matrix is used to represent a simplified shape evolution enforced on all inclusions. The mechanical anisotropy develops due to the alignment of elongated inclusions. The effective anisotropy is quantified using the differential effective medium (DEM) approach. The model can be run for any deformation path and an arbitrary viscosity ratio between the inclusion and host phase. We focus on the case of simple shear and weak inclusions. The shape evolution of the representative inclusion is largely insensitive to the anisotropy development and to parameter variations in the studied range. An initial hardening stage is observed up to a shear strain of gamma = 1 irrespective of the inclusion fraction. The hardening is followed by a softening stage related to the developing anisotropy and its progressive rotation toward the shear direction. The traction needed to maintain a constant shear rate exhibits a fivefold drop at gamma = 5 in the limiting case of an inviscid inclusion. Numerical simulations show that our analytical model provides a good approximation to the actual evolution of a two-phase inclusion-host composite. However, the inclusions develop complex sigmoidal shapes resulting in the formation of an S-C fabric. We attribute the observed drop in the effective normal viscosity to this structural development. We study the localization potential in a rock column bearing varying fraction of inclusions. In the inviscid inclusion case, a strain jump from gamma = 3 to gamma = 100 is observed for a change of the inclusion fraction from 20% to 33%.
Resumo:
Our view of the RNA polymerase III (Pol III) transcription machinery in mammalian cells arises mostly from studies of the RN5S (5S) gene, the Ad2 VAI gene, and the RNU6 (U6) gene, as paradigms for genes with type 1, 2, and 3 promoters. Recruitment of Pol III onto these genes requires prior binding of well-characterized transcription factors. Technical limitations in dealing with repeated genomic units, typically found at mammalian Pol III genes, have so far hampered genome-wide studies of the Pol III transcription machinery and transcriptome. We have localized, genome-wide, Pol III and some of its transcription factors. Our results reveal broad usage of the known Pol III transcription machinery and define a minimal Pol III transcriptome in dividing IMR90hTert fibroblasts. This transcriptome consists of some 500 actively transcribed genes including a few dozen candidate novel genes, of which we confirmed nine as Pol III transcription units by additional methods. It does not contain any of the microRNA genes previously described as transcribed by Pol III, but reveals two other microRNA genes, MIR886 (hsa-mir-886) and MIR1975 (RNY5, hY5, hsa-mir-1975), which are genuine Pol III transcription units.
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The patterns of development of the vestibular nuclei (VN) and their main connections involving glutamate neurotransmission offer a good model for studying the function of the glial-derived neuromodulator D-serine in synaptic plasticity. In this study we show that D-serine is present in the VN and we analyzed its distribution and the levels of expression of serine racemase and D-amino acid oxidase (D-AAO) at different stages of postnatal (P) development. From birth to P21, high levels of D-serine were detected in glial cells and processes in all parts of the VN. This period corresponded to high expression of serine racemase and low expression of D-AAO. On the other hand, in the mature VN D-serine displayed very low levels and was mainly localized in neuronal cell bodies and dendrites. This drop of D-serine in adult stages corresponded to an increasing expression of D-AAO at mature stages. High levels of glial D-serine during the first 3 weeks of postnatal development correspond to an intense period of plasticity and synaptogenesis and maturation of VN afferents, suggesting that D-serine could be involved in these phenomena. These results demonstrate for the first time that changes in D-serine levels and distribution occur during postnatal development in the central nervous system. The strong decrease of D-serine levels and the glial-to-neuronal switch suggests that D-serine may have distinct functional roles depending on the developmental stage of the vestibular network.
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OBJECTIVE: Although genetic factors have been implicated in the etiology of bipolar disorder, no specific gene has been conclusively identified. Given the link between abnormalities in serotonergic neurotransmission and bipolar disorder, a candidate gene association approach was applied to study the involvement of the monoamine oxidase A (MAOA) gene, which codes for a catabolic enzyme of serotonin, in the susceptibility to bipolar disorder. METHOD: In France and Switzerland, 272 patients with bipolar disorder and 122 healthy subjects were typed for three polymorphic markers of the MAOA gene: the MAOA-CA repeat, the MAOA restriction fragment length polymorphism (RFLP), and a repeat directly adjacent to the variable number of tandem repeats (VNTR) locus. RESULTS: A significant difference in the distribution of the alleles for the MAOA-CA repeat was observed between the female bipolar patients and comparison group. CONCLUSIONS: The results obtained in the French and Swiss population confirm findings from two studies conducted in the United Kingdom.
Resumo:
Glucose-dependent insulinotropic polypeptide (GIP) is a hormone secreted by the endocrine K-cells from the duodenum that stimulates glucose-induced insulin secretion. Here, we present the molecular characterization of the human pancreatic islet GIP receptor. cDNA clones for the GIP receptor were isolated from a human pancreatic islet cDNA library. They encoded two different forms of the receptor, which differed by a 27-amino acid insertion in the COOH-terminal cytoplasmic tail. The receptor protein sequence was 81% identical to that of the rat GIP receptor. When expressed in Chinese hamster lung fibroblasts, both forms of the receptor displayed high-affinity binding for GIP (180 and 600 pmol/l). GIP binding was displaced by < 20% by 1 mumol/l glucagon, glucagon-like peptide (GLP-I)(7-36) amide, vasoactive intestinal peptide, and secretin. However exendin-4 and exendin-(9-39) at 1 mumol/l displaced binding by approximately 70 and approximately 100% at 10 mumol/l. GIP binding to both forms of the receptor induced a dose-dependent increase in intracellular cAMP levels (EC50 values of 0.6-0.8 nmol/l) but no elevation of cytoplasmic calcium concentrations. Interestingly, both exendin-4 and exendin-(9-39) were antagonists of the receptor, inhibiting GIP-induced cAMP formation by up to 60% when present at a concentration of 10 mumol/l. Finally, the physical and genetic chromosomal localization of the receptor gene was determined to be on 19q13.3, close to the ApoC2 gene. These data will help study the physiology and pathophysiology of the human GIP receptor.
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Odor detection and discrimination by olfactory systems in vertebrates and invertebrates depend both on the selective expression of individual olfactory receptor genes in subpopulations of olfactory sensory neurons, and on the targeting of the encoded proteins to the exposed, ciliated endings of sensory dendrites. Techniques to visualize the expression and localization of olfactory receptor gene products in vivo have been essential to reveal the molecular logic of peripheral odor coding and to permit investigation of the developmental and cellular neurobiology of this sensory system. Here, we describe methods for detection of olfactory receptor transcripts and proteins in the antennal olfactory organ of the fruit fly, Drosophila melanogaster, an important genetic model organism. We include protocols both for antennal cryosections and whole-mount antennae. These methods can be adapted for detection of receptor expression in other olfactory and gustatory tissues in Drosophila, as well as in the chemosensory systems of other insects.
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The influence of second phases (e.g., pyroxenes) on olivine grain size was studied by quantitative microfabric analyses of samples of the Hilti massif mantle shear zone (Semail ophiolite, Oman). The microstructures range from porphyroclastic tectonites to ultramylonites, from outside to the center of the shear zone. Starting at conditions of ridge-related flow, they formed under continuous cooling leading to progressive strain localization. The dependence of the average olivine grain size on the second-phase content can be split into a second-phase controlled and a dynamic recrystallization-controlled field. In the former, the olivine grain size is related to the ratio between the second-phase grain size and volume fraction (Zener parameter). In the latter, dynamic recrystallization manifested by a balance between grain growth and grain size reduction processes yields a stable olivine grain size. In both fields the average olivine and second-phase grain size decreases with decreasing temperature. Combining the microstructural information with deformation mechanism maps suggests that the porphyroclastic tectonites (similar to 1100 degrees C) and mylonites (similar to 800 degrees C) formed under the predominance of dislocation creep. Since olivine-rich layers are intercalated with layer parallel, polymineralic bands in the mylonites, nearly equiviscous conditions can be assumed. In the ultramylonites, diffusion creep represents the major deformation mechanism in the polymineralic layers. It is this switch in deformation mechanism from dislocation creep to diffusion creep that forces strain to localize in the fine-grained polymineralic domains at low temperatures (<similar to 700 degrees C), underlining the role of the second phases on strain localization in cooling mantle rocks.
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Neurocognitive impairment constitutes a core feature of bipolar illness. The main domains affected are verbal memory, attention, and executive functions. Deficits in these areas as well as difficulties to get functional remission seem to be increased associated with illness progression. Several studies have found a strong relationship between neurocognitive impairment and low functioning in bipolar disorder, as previously reported in other illnesses such as schizophrenia. Cognitive remediation strategies, adapted from work conducted with traumatic brain injury patients and applied to patients with schizophrenia, also need to be adapted to individuals with bipolar disorders. Early intervention using functional remediation, involves neurocognitive techniques and training, but also psychoeducation on cognition-related issues and problem-solving within an ecological framework.
Resumo:
BACKGROUND: Studies in bipolar disorder (BD) to date are limited in their ability to provide a whole-disease perspective--their scope has generally been confined to a single disease phase and/or a specific treatment. Moreover, most clinical trials have focused on the manic phase of disease, and not on depression, which is associated with the greatest disease burden. There are few longitudinal studies covering both types of patients with BD (I and II) and the whole course of the disease, regardless of patients' symptomatology. Therefore, the Wide AmbispectiVE study of the clinical management and burden of Bipolar Disorder (WAVE-bd) (NCT01062607) aims to provide reliable information on the management of patients with BD in daily clinical practice. It also seeks to determine factors influencing clinical outcomes and resource use in relation to the management of BD. METHODS: WAVE-bd is a multinational, multicentre, non-interventional, longitudinal study. Approximately 3000 patients diagnosed with BD type I or II with at least one mood event in the preceding 12 months were recruited at centres in Austria, Belgium, Brazil, France, Germany, Portugal, Romania, Turkey, Ukraine and Venezuela. Site selection methodology aimed to provide a balanced cross-section of patients cared for by different types of providers of medical aid (e.g. academic hospitals, private practices) in each country. Target recruitment percentages were derived either from scientific publications or from expert panels in each participating country. The minimum follow-up period will be 12 months, with a maximum of 27 months, taking into account the retrospective and the prospective parts of the study. Data on demographics, diagnosis, medical history, clinical management, clinical and functional outcomes (CGI-BP and FAST scales), adherence to treatment (DAI-10 scale and Medication Possession Ratio), quality of life (EQ-5D scale), healthcare resources, and caregiver burden (BAS scale) will be collected. Descriptive analysis with common statistics will be performed. DISCUSSION: This study will provide detailed descriptions of the management of BD in different countries, particularly in terms of clinical outcomes and resources used. Thus, it should provide psychiatrists with reliable and up-to-date information about those factors associated with different management patterns of BD. TRIAL REGISTRATION NO: ClinicalTrials.gov: NCT01062607.
Resumo:
OBJECTIVE: This study aims to differentiate schizoaffective disorder (SAD) and bipolar-I-disorder (BD) in first-episode psychotic mania (FEPM). METHODS: All 134 patients from an epidemiological first-episode psychosis cohort (N=786) with FEPM and an 18-month follow-up final diagnosis of SAD (n=36) or BD (n=98) were assessed with respect to pre-treatment, baseline and outcome differences. Second, patients with baseline BD who shifted (shifted BD) or did not shift to SAD (stable BD) over the follow-up period were compared regarding pre-treatment and baseline differences. RESULTS: SAD patients displayed a significantly longer duration of untreated psychosis (DUP; effect size r=0.35), a higher illness-severity at baseline (r=0.20) and more traumatic events (Cramer-V=0.19). SAD patients displayed a significantly higher non-adherence rate (Cramer-V=0.19); controlling for time in treatment and respective baseline scores, SAD patients had significantly worse illness severity (CGI-S; partial η(2)=0.12) and psychosocial functioning (GAF; partial η(2)=0.07) at 18-months, while BD patients were more likely to achieve remission of positive symptoms (OR=4.9, 95% CI=1.8-13.3; p=0.002) and to be employed/occupied (OR=7.7, 95% CI=2.4-24.4, p=0.001). The main discriminator of stable and shifted BD was a longer DUP in patients shifting from BD to SAD. CONCLUSIONS: It is difficult to distinguish BD with psychotic symptoms and SAD in patients presenting with FEPM. Longer DUP is related to SAD and to a shift from BD to SAD. Compared to BD, SAD had worse outcomes and higher rates of non-adherence with medication. Despite these differences, both diagnostic groups need careful dimensional assessment and monitoring of symptoms and functioning in order to choose the right treatment.
Resumo:
In the last five years, Deep Brain Stimulation (DBS) has become the most popular and effective surgical technique for the treatent of Parkinson's disease (PD). The Subthalamic Nucleus (STN) is the usual target involved when applying DBS. Unfortunately, the STN is in general not visible in common medical imaging modalities. Therefore, atlas-based segmentation is commonly considered to locate it in the images. In this paper, we propose a scheme that allows both, to perform a comparison between different registration algorithms and to evaluate their ability to locate the STN automatically. Using this scheme we can evaluate the expert variability against the error of the algorithms and we demonstrate that automatic STN location is possible and as accurate as the methods currently used.