982 resultados para D2
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A central feature of drugs of abuse is to induce gene expression in discrete brain structures that are critically involved in behavioral responses related to addictive processes. Although extracellular signal-regulated kinase (ERK) has been implicated in several neurobiological processes, including neuronal plasticity, its role in drug addiction remains poorly understood. This study was designed to analyze the activation of ERK by cocaine, its involvement in cocaine-induced early and long-term behavioral effects, as well as in gene expression. We show, by immunocytochemistry, that acute cocaine administration activates ERK throughout the striatum, rapidly but transiently. This activation was blocked when SCH 23390 [a specific dopamine (DA)-D1 antagonist] but not raclopride (a DA-D2 antagonist) was injected before cocaine. Glutamate receptors of NMDA subtypes also participated in ERK activation, as shown after injection of the NMDA receptor antagonist MK 801. The systemic injection of SL327, a selective inhibitor of the ERK kinase MEK, before cocaine, abolished the cocaine-induced ERK activation and decreased cocaine-induced hyperlocomotion, indicating a role of this pathway in events underlying early behavioral responses. Moreover, the rewarding effects of cocaine were abolished by SL327 in the place-conditioning paradigm. Because SL327 antagonized cocaine-induced c-fos expression and Elk-1 hyperphosphorylation, we suggest that the ERK intracellular signaling cascade is also involved in the prime burst of gene expression underlying long-term behavioral changes induced by cocaine. Altogether, these results reveal a new mechanism to explain behavioral responses of cocaine related to its addictive properties.
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A series of new benzolactam derivatives was synthesized and the derivatives were evaluated for theiraffinities at the dopamine D1, D2, and D3 receptors. Some of these compounds showed high D2 and/orD3 affinity and selectivity over the D1 receptor. The SAR study of these compounds revealed structuralcharacteristics that decisively influenced their D2 and D3 affinities. Structural models of the complexesbetween some of the most representative compounds of this series and the D2 and D3 receptors wereobtained with the aim of rationalizing the observed experimental results. Moreover, selected compoundsshowed moderate binding affinity on 5-HT2A which could contribute to reducing the occurrence of extrapyramidalside effects as potential antipsychotics.
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FANCM binds and remodels replication fork structures in vitro. We report that in vivo, FANCM controls DNA chain elongation in an ATPase-dependent manner. In the presence of replication inhibitors that do not damage DNA, FANCM counteracts fork movement, possibly by remodelling fork structures. Conversely, through damaged DNA, FANCM promotes replication and recovers stalled forks. Hence, the impact of FANCM on fork progression depends on the underlying hindrance. We further report that signalling through the checkpoint effector kinase Chk1 prevents FANCM from degradation by the proteasome after exposure to DNA damage. FANCM also acts in a feedback loop to stabilize Chk1. We propose that FANCM is a ringmaster in the response to replication stress by physically altering replication fork structures and by providing a tight link to S-phase checkpoint signalling.
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The complex etiology of schizophrenia has prompted researchers to develop clozapine-related multitargetstrategies to combat its symptoms. Here we describe a series of new 6-aminomethylbenzofuranones in aneffort to find new chemical structures with balanced affinities for 5-HT2 and dopamine receptors. Throughbiological and computational studies of 5-HT2A and D2 receptors, we identified the receptor serine residuesS3.36 and S5.46 as the molecular keys to explaining the differences in affinity and selectivity betweenthese new compounds for this group of receptors. Specifically, the ability of these compounds to establishone or two H-bonds with these key residues appears to explain their difference in affinity. In addition, wedescribe compound 2 (QF1004B) as a tool to elucidate the role of 5-HT2C receptors in mediating antipsychoticeffects and metabolic adverse events. The compound 16a (QF1018B) showed moderate to high affinitiesfor D2 and 5-HT2A receptors, and a 5-HT2A/D2 ratio was predictive of an atypical antipsychotic profile.
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The concentrations of the general neuronal markers D2-protein (N-CAM), D3-protein and neuron specific enolase (NSE) in reaggregating cultures of fetal rat telencephalon cells were affected by the presence of 30 nM triiodothyronine in the defined culture medium. The extent of normal developmental changes were enhanced by triiodothyronine, as demonstrated by crossed immunoelectrophoresis. From 13 to 19 days in culture, the concentration of D2-protein decreased, and the concentrations of both D3-protein and NSE increased. Nerve growth factor (NGF) was without effect on the development of these general neuronal markers. However, as shown previously both triiodothyronine and NGF increased the activity of choline acetyltransferase, a marker for cholinergic neurons. The results suggest an enhanced overall differentiation of several types of telencephalon neurons in the presence of triiodothyronine, and a specific stimulation of cholinergic telencephalon neurons by NGF.
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RésuméDie Grabung 1989/5 der Archäologischen Bodenforschung Basel-Stadt im Zentrum der Siedlung Basel-Gasfabrik umfasste eine Fläche von etwa 900 m2. Auf etwa 370 m2 konnten intakte latènezeitliche Strukturen festgestellt werden. Der ehemalige Gehhorizont und die darunter liegende Siedlungsschicht waren jedoch nirgends erhalten geblieben.Die in den gewachsenen Boden eingetieften Pfostengrub en erlaubten die Rekonstrulction von zwei rechteckigen Häusern mit je vier Eckpfosten, die als Wohngebäude gedeutet werden.Über das ganze Areal verteilt wurden 14 Gruben unterschiedlicher Form und Grösse ganz oder teilweise ausgegraben. Bei der flachen Grube 261 handelt es sich wohl um den eingetieften Bereich eines kleinen Grubenhauses, das für nicht näher bestimmbare handwerkliche Aktivitäten genutzt wurde. Die beiden mit einem Pfostenbau überdeckten Gruben 258 und 259 können hingegen mit grosser Wahrscheinlichkeit als Schmiedegruben gedeutet werden. In Grube 258 waren gar die Reste von zwei Feuerstellen und der Unterbau eines kaminartigen Abzugs in situ erhalten. Die Gruben 253, 254A, 254B, 255,256 und 257 mit Resten von Lehmausideidungen dienten vermutlich als Getreidesilos. Sie liegen alle im Zentrum des Grabungsareals im Bereich einer anstehenden Lehmschicht. Bei einigen weiteren Gruben könnte es sich um Keller handeln.Im Westen der Grabungsfläche kamen die Heizkanäle von zwei Töpferöfen zum Vorschein. Es handelt sich um einfache Kuppelöfen mit gegenständiger Feuerung. In geringer Entfernung lagen drei kleine Gruben, die vielleicht zur Aufbereitung des Töpferlehms dienten. Aufgrund der klimatischen Verhältnisse ist mit einem saisonalen Betrieb der Töpferöfen während der Sommermonate zu rechnen. Die notwendigen Arbeiten wurden mit grosser Wahrscheinlichkeit von Frauen ausgeführt, da die Männer während dieser Jahreszeit in der Landwirtschaft beschäftigt waren. Der Töpfereibetrieb produzierte grössere Serien scheibengedrehter, reduzierend gebrannter Feinkeramik, von der im Bereich der Öfen zahlreiche Scherben gefunden wurden.Die räumliche Organisation der Bebauung zeugt von einer einheitlichen und wohl kontinuierlichen Nutzung der Grabungsfläche. ImWesten gruppieren sich Haus 1 und die Einrichtungen des Töpfereibetriebs um eine unbebaute Hofzone. Nach Osten zu folgt dann die Zone mit den Getreidesilos. Das östliche Bauensemble besteht aus Haus 2, den Schmiedegruben, dem Grubenhaus sowie einer mutmasslichen Kellergrube. Stratigra-phische Überschneidungen von Befunden sind nur im Bereich der Töpferöfen vorhanden.Die Grubenfüllungen erwiesen sich als sehr fundreich. Die gegen 20000 Keramikscherben repräsentieren das gesamte Spektrum der aus Basel-Gasfabrik bekannten einheimischen Grobund Feinkeramik. Bei den seltenen Scherben von Graphittonkeramik handelt es sich um Importe aus dem ostkeltischen Bereich.Die zahlreichen Amphorenscherben stammen von mindestens 35 verschiedenen Gefässindividuen des Typs Dressel 1A, von denen aber immer nur ein kleiner Prozentsatz vorhanden war. Die Typologie und die Datierung der Befunde zeigen, dass der Amphorenimport erst im Laufe von LT D1 einsetzte.Unter den Kleinfunden verdienen die zahlreichen Silber- und Potinmünzen sowie die Glasfunde besondere Erwähnung. Das Fragment eines möglicherweise latènezeitlichen Glasgefässes stammt leider aus einem unsicheren Fundzusammenhang.Die über 70 Fibeln und Fibelteile sind zu 70% aus Bronze gefertigt. Das Fibelspektrum wird von den Nauheimer Fibeln dominiert. Besonders bei den Eisenfibeln konnten aber auch typologisch ältere Typen identifiziert werden, welche in die Stufen LT C2 und LT D1a gehören. Bei den Glasarmringen machen mittellatènezeitliche Typen gegen 20 % der Fundmenge aus.Von besonderer Bedeutung sind die 23 Menschenknochen von 19 verschiedenen Individuen. Es handelt sich dabei um einen fast vollständigen Schädel, Schädelteile und Fragmente von Langknochen sowie wenige weitere Skelettteile. Die Zusammensetzung des Ensembles und der Zustand der Einzelknochen lässt sich sehr gut mit den Menschenknochen aus den Altgrabungen von Basel-Gasfabrik und aus Manching vergleichen. Eine detaillierte Untersuchung zeigt, dass die Knochen am Ende eines langwierigen Totenrituals, das aufgrund ethno - logischer Vergleiche als mehrstufige Bestattung bezeichnet werden kann, in der Siedlung vergraben wurden. In der Umgebung der Menschenknochen wurden in einigen Fällen auffallend viele Amphorenscherben gefunden, die bezeugen, dass der importierte Wein bei diesen Riten eine bedeutende Rolle spielte. Wahrscheinlich wurden diese Knochen auch als Ahnenrelikte verehrt.Neben den mehrstufigen Bestattungen konnten auch zwei Säuglingsbestattungen identifiziert werden.Die Analyse von Fundmenge und Fundverteilung in den Gruben zeigt, dass die Funde nicht direkt, sondern auf dem Umweg über primäre Deponien in die Gruben gelangten. In den pri-mären Deponien wurden Funde über längere Zeit akkumuliert und mit verschiedenen Erdmaterialien intensiv vermischt.Für den Grossteil der Funde wird eine profane Deutung als Abfälle vorgeschlagen. Daneben können aber auch einige Funde als gezielte Deponierungen angesprochen werden. Ver-schiedene Fibelpaare und wahrscheinlich auch Münzen wurden wohl als Opfergaben in die Gruben gegeben. Ein Zusammenhang dieser Opfergaben mit den Bestattungen von Men-schenknochen ist nicht erkennbar.Die Datierung der Funde zeigt einen Siedlungsbeginn in LT C2 und ein Ende noch vor dem Beginn der Stufe LT D2. Die Kombination dieser Datierungen mit den stratigraphischen Überschneidungen einiger Befunde erlaubt eine Rekonstruktion der Besiedlungsentwicklung auf dem Grabungsareal. Die Gruben 259 und 260 wurden bereits in LT C2 verfüllt, die Schmiedegrube 259 anschliessend durch Grube 258 ersetzt. Die beiden Töpferöfen waren nacheinander in LT D1 in Betrieb. Die beiden Häuser können leider nicht genauer datiert werden.Die Besiedlung des Area's setzte noch vor 150 V. Chr. ein und dauerte maximal 80 Jahre.Die Synthese aller Untersuchungen zeigt, dass auf dem Grabungsareal eine Gruppe von etwa 15 Personen ansässig war, die sich v. a. der Landwirtschaft widmete. Die handwerkliche Tätigkeit (Töpferei, Metallverarbeitung) erreichte keinen vollberuflichen Standard.Die dörfliche Siedlungsgemeinschaft bestand aus bäuerlichen Selbstversorgern, mit anderen Gemeinschaften wurden jedoch Keramik, Handwerksprodukte und Schlachtvieh ausge-tauscht. Von besonderer Bedeutung war offenbar das Getreide, das in grossen Mengen in der Siedlung gelagert wurde und mit grosser Wahrscheinlichkeit für den Export bestimmt war. Die Herkunft dieses Getreides und die sozialen Strukturen hinter diesem Austausch sind nicht ldar, aber mit hoher Wahrscheinlichkeit wurden durch den Getreideexport die Importe wie Salz, Rohstoffe (Metall) und Wein ermöglicht.
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Peroxisome proliferator-activated receptors (PPARs) are essential in glucose and lipid metabolism and are implicated in metabolic disorders predisposing to atherosclerosis, such as diabetes and dyslipidemia. Conversely, antidiabetic glitazones and hypolipidemic fibrate drugs, known as PPARgamma and PPARalpha ligands, respectively, reduce the process of atherosclerotic lesion formation, which involves chronic immunoinflammatory processes. Major histocompatibility complex class II (MHC-II) molecules, expressed on the surface of specialized cells, are directly involved in the activation of T lymphocytes and in the control of the immune response. Interestingly, expression of MHC-II has recently been observed in atherosclerotic plaques, and it can be induced by the proinflammatory cytokine interferon-gamma (IFN-gamma) in vascular cells. To explore a possible role for PPAR ligands in the regulation of the immune response, we investigated whether PPAR activation affects MHC-II expression in atheroma-associated cells. In the present study, we demonstrate that PPARgamma but not PPARalpha ligands act as inhibitors of IFN-gamma-induced MHC-II expression and thus as repressors of MHC-II-mediated T-cell activation. All different types of PPARgamma ligands tested inhibit MHC-II. This effect of PPARgamma ligands is due to a specific inhibition of promoter IV of CIITA and does not concern constitutive expression of MHC-II. Thus, the beneficial effects of antidiabetic PPARgamma activators on atherosclerotic plaque development may be partly explained by their repression of MHC-II expression and subsequent inhibition of T-lymphocyte activation.
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A proposta deste estudo foi de avaliar o desenvolvimento pós-embrionário de Pattonella intermutans (Thomson, 1869) em dietas artificiais preparadas com agar-agar. Dieta D1: leite em pó integral + fermento biológico; Dieta D2: leite em pó integral + fermento biológico + caseína; Dieta D3: leite em pó integral + ovo cru; Dieta D4: carne bovina moída (dieta controle). A carne bovina moída foi a dieta mais eficiente (peso larval de 195,63 mg e viabilidade de neolarva a adulto de 86,5%), quando comparada com as dietas artificiais. Os seguintes resultados foram obtidos para o grupo experimental: Dieta D3: 180,15 mg e 63,5%; Dieta D2: 141,07 mg e 61% e na Dieta D1: 147,98 mg e 51,5%.
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Gas chromatography (GC) is an analytical tool very useful to investigate the composition of gaseous mixtures. However, hydrogen (H2) detection after a GC separation is only possible with a Thermal Conductivity Detector (TCD), a Helium Ionisation Detector (HID) or expensive Atomic Emission Detector (AED). Recently, indirect H2 detection by GC coupled to mass spectrometry (MS) was demonstrated but the mechanism of carrier gas protonation remained unclear. With electron impact as ionisation source of MS and helium (He) as GC carrier gas, H2 is not ionised according the expected Penning ionisation neither according to the Associative ionisation. Rearrangement ionisation (RI) was found to be the main channel for H2 and D2 ionisation under GC-MS conditions used in most of laboratories using GC-MS, leading to the formation of [He−H]+ and [He−D]+ ions.
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Résumé du travail de thèse Introduction : Les différentes cellules endothéliales du lit vasculaire ont de nombreuses similitudes fonctionnelles et morphologiques. Cependant, elles présentent également une importante hétérogénéité structurelle et fonctionnelle qui peut avoir des implications notamment dans l'angiogenèse et le développement des maladies cardio-vasculaires. Peu d'études ont été publiées au sujet de l'expression et de la distribution des marqueurs endothéliaux dans les tissus humain normaux. Objectif : Nous avons étudié l'expression immunohistochimique des marqueurs endothéliaux CD31, CD34, vWF et Fli-1 dans les vaisseaux périphériques du rein, du poumon, de la rate, du foie, du cour et des gros vaisseaux ; incluant l'aorte, la veine cave inférieure, l'artère rénale ainsi que les artères et veines pulmonaires et fémorales. Matériel et méthodes : Les échantillons tissulaires ont été obtenus à partir de matériel d'autopsie et de biopsies. Le matériel a été fixé en formaline et inclus en paraffine. Les coupes de paraffine ont été colorées immunohistochimiquement avec CD31, CD34 et vWF. Les biopsies ont également été colorées immunohistochimiquement avec Fli-1, D2-40 et Lyve-1. Résultats : L'expression immunohistochimique de ces marqueurs est hétérogène dans les différents organes étudiés. Dans le rein, l'endothélium fenêtré des glomérules exprime fortement CD31 et CD34. Par contre, il n'exprime pas ou alors de manière faible et focale vWF. Dans le poumon, les capillaires alvéolaires expriment fortement CD31 et CD34 mais sont habituellement négatifs pour le vWF. L'expression de vWF augmente graduellement avec le calibre vasculaire dans le poumon. Les sinusoïdes de la rate expriment CD31 de manière diffuse mais ils n'expriment pas CD34. Les sinusoïdes du foie expriment CD31 de part et d'autre des lobules. Par contre, CD34 est exprimé seulement dans la région périportale. L'expression de Fli-1 dans les cellules endothéliales est ubiquitaire et ne varie pas suivant le type de vaisseau ou d'organe. Fli-1 est également exprimé dans d'autres types de cellules, essentiellement des lymphocytes. D2-40 est exprimé seulement dans l'endothélium des vaisseaux lymphatiques. L'expression de Lyve-1 dans ce matériel de routine était inconstante et non reproductible. Conclusion : Ces résultats indiquent que l'expression des marqueurs endothéliaux CD31, CD34 et vWF est hétérogène dans le lit vasculaire et qu'elle varie entre différents vaisseaux et différents compartiments anatomiques du même organe. D2-40 ne marque que les cellules endothéliales lymphatiques.
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A máxima eficiência da calagem depende, além da qualidade do material corretivo, de uma incorporação adequada quanto à profundidade e homogeneidade. Diante disto, objetivou-se avaliar o efeito dos modos de incorporação de calcário na produção da aveia preta e na correção da acidez no perfil do solo. Para isto, foi realizado um experimento em um Latossolo Vermelho distrófico textura argilosa, na região do Triângulo Mineiro, em Uberlândia (MG), no período de maio de 1995 a fevereiro de 1996. O delineamento experimental foi em parcelas subdivididas, com as parcelas principais organizadas em blocos, com três repetições. As parcelas foram constituídas pelos modos de incorporação do calcário: grade aradora pesada e grade niveladora GP+GN (14x34"); modo tradicional, com aração (4x26") e grade niveladora A+GN (60x22"); grade aradora superpesada e grade niveladora GSP+GN (14x34"); nas subparcelas, pelas doses de calcário dolomítico, como se segue: D0 = zero de calcário; D1 = dose para elevar V = 70%; D2 = dose para elevar V = 100%, que corresponderam a 0; 6,0 e 9,2tha-1, respectivamente. O modo de incorporação do calcário influiu na eficiência da calagem no perfil do solo. A gradagem pesada não foi adequada para a incorporação do calcário. O arado de disco mais a gradagem niveladora tiveram desempenho satisfatório, atingindo até 0,20m de profundidade. A gradagem superpesada proporcionou maior uniformidade e profundidade de incorporação, com neutralização da acidez do solo até 0,30m de profundidade.
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Introduction: The primary somatosensory cortex (SI) contains Brodmann areas (BA) 1, 2, 3a, and 3b. Research in non-human primates showed that BAs 3b, 1, and 2 each contain one full representation of the hand with separate representations for each finger. This research also showed that the finger representation in BA3b has larger and clearer finger somatotopy than BA1 and 2. Although several efforts to map finger somatotopy in SI by fMRI have been made at 1.5 and 3T these studies have yielded variable results and were not able to detect single subject finger somatotopy, probably due to the limited spatial extent of the cortical areas representing a digit (close to the resolution in most fMRI experiments), complications due to acquisition of consistent maps for individual subjects (Schweizer et al 2008), or inter-individual variability in sulcal anatomy impeding group studies. Here, we used 7T fMRI to investigate finger somatotopy in SI, some of its functional characteristics, and its reproducibility. Methods: Eight right-handed male subjects were scanned on a 7T scanner (Siemens Medical, Germany) with an 8-channel Tx/Rx rf-coil (Rapid Biomedical, Germany). 1.3x1.3x1.3mm3 resolution fMRI data were acquired using a sinusoidal readout EPI sequence (Speck et al, 2008) and FOV=210mm, TE/TR=27ms/2.5s, GRAPPA=2. Each volume contained 28 transverse slices covering SI. A single EPI volume with 64 slices was acquired to aid coregistration. 1x1x1mm3 anatomical data were acquire using the MP2RAGE sequence (Marques et al, 2009; TE/TR/TI1,2/TRmprage=2.63ms/7.2ms/0.9,3.2s/5s). Subjects were positioned supine in the scanner with their right arm comfortably against the magnet bore. An experimenter was positioned at the entrance of the bore where he could easily reach and stroke successively the two distal phalanxes of each digit. The order of stroked digit was D1 (thumb)-D3-D5-D2-D4, with 20s ON, 10s OFF alternated. This sequence was repeated four times per run and two functional runs were acquired per subject. Realignment, smoothing (FWHM 2 mm), coregistration of the anatomical to the fMRI data and calculation of t-statistics were done using SPM8. An SI mask was obtained via an F-contrast (p<0.001) over all digits. Within the mask, voxels were labeled with the number of the digit demonstrating the highest t-value for that particular voxel. Results: For all subjects, areas corresponding to the five digits were identified in contralateral SI. BA3b showed the most consistent somatotopic finger representation (see an example in Fig.1). The five digits were localized in a consecutive order in the cortex, with D1 most anterior, inferior and distal and D5, most posterior, superior and medial (mean distance between centres of mass of digit representations ±stderr: 4.2±0.7mm; see Fig. 2). The analysis of average beta values within each finger representation region revealed the specificity of the somatotopic region to the tactile input for each tested finger (except digit 4 and 5). Five of these subjects also presented an orderly and consecutive representation of the five digits in BA1 and 2. Conclusions: Our data reveal that the increased BOLD sensitivity at 7T and the high spatial resolution used in this study allow consistent somatotopic mapping using human touch as a stimulus and that human SI contains at least three separate regions that contain five separate representations of all single contralateral fingers. Moreover, adjacent fingers were represented at adjacent cortical regions across the three SI regions. The spatial organization of SI as reflected in individual subject topography corresponds well with previous electrophysiological data in non-human primates. The small distance between digit representations highlights the need for the high spatial resolution available at 7T.
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TERMINOLOGY AND PRINCIPLES OF COMBINING ANTIPSYCHOTICS WITH A SECOND MEDICATION: The term "combination" includes virtually all the ways in which one medication may be added to another. The other commonly used terms are "augmentation" which implies an additive effect from adding a second medicine to that obtained from prescribing a first, an "add on" which implies adding on to existing, possibly effective treatment which, for one reason or another, cannot or should not be stopped. The issues that arise in all potential indications are: a) how long it is reasonable to wait to prove insufficiency of response to monotherapy; b) by what criteria that response should be defined; c) how optimal is the dose of the first monotherapy and, therefore, how confident can one be that its lack of effect is due to a truly inadequate response? Before one considers combination treatment, one or more of the following criteria should be met; a) monotherapy has been only partially effective on core symptoms; b) monotherapy has been effective on some concurrent symptoms but not others, for which a further medicine is believed to be required; c) a particular combination might be indicated de novo in some indications; d) The combination could improve tolerability because two compounds may be employed below their individual dose thresholds for side effects. Regulators have been concerned primarily with a and, in principle at least, c above. In clinical practice, the use of combination treatment reflects the often unsatisfactory outcome of treatment with single agents. ANTIPSYCHOTICS IN MANIA: There is good evidence that most antipsychotics tested show efficacy in acute mania when added to lithium or valproate for patients showing no or a partial response to lithium or valproate alone. Conventional 2-armed trial designs could benefit from a third antipsychotic monotherapy arm. In the long term treatment of bipolar disorder, in patients responding acutely to the addition of quetiapine to lithium or valproate, this combination reduces the subsequent risk of relapse to depression, mania or mixed states compared to monotherapy with lithium or valproate. Comparable data is not available for combination with other antipsychotics. ANTIPSYCHOTICS IN MAJOR DEPRESSION: Some atypical antipsychotics have been shown to induce remission when added to an antidepressant (usually a SSRI or SNRI) in unipolar patients in a major depressive episode unresponsive to the antidepressant monotherapy. Refractoriness is defined as at least 6 weeks without meeting an adequate pre-defined treatment response. Long term data is not yet available to support continuing efficacy. SCHIZOPHRENIA: There is only limited evidence to support the combination of two or more antipsychotics in schizophrenia. Any monotherapy should be given at the maximal tolerated dose and at least two antipsychotics of different action/tolerability and clozapine should be given as a monotherapy before a combination is considered. The addition of a high potency D2/3 antagonist to a low potency antagonist like clozapine or quetiapine is the logical combination to treat positive symptoms, although further evidence from well conducted clinical trials is needed. Other mechanisms of action than D2/3 blockade, and hence other combinations might be more relevant for negative, cognitive or affective symptoms. OBSESSIVE-COMPULSIVE DISORDER: SSRI monotherapy has moderate overall average benefit in OCD and can take as long as 3 months for benefit to be decided. Antipsychotic addition may be considered in OCD with tic disorder and in refractory OCD. For OCD with poor insight (OCD with "psychotic features"), treatment of choice should be medium to high dose of SSRI, and only in refractory cases, augmentation with antipsychotics might be considered. Augmentation with haloperidol and risperidone was found to be effective (symptom reduction of more than 35%) for patients with tics. For refractory OCD, there is data suggesting a specific role for haloperidol and risperidone as well, and some data with regard to potential therapeutic benefit with olanzapine and quetiapine. ANTIPSYCHOTICS AND ADVERSE EFFECTS IN SEVERE MENTAL ILLNESS: Cardio-metabolic risk in patients with severe mental illness and especially when treated with antipsychotic agents are now much better recognized and efforts to ensure improved physical health screening and prevention are becoming established.