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Copyright of Canadian Journal of Psychiatry is the property of Sage Publications Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Chaperone-mediated autophagy (CMA) is a major pathway of lysosomal proteolysis critical for cellular homeostasis and metabolism, and whose defects have been associated with several human pathologies. While CMA has been well described in mammals, functional evidence has only recently been documented in fish, opening up new perspectives to tackle this function under a novel angle. Now we propose to explore CMA functions in the rainbow trout (RT, Oncorhynchus mykiss ), a fish species recognized as a model organism of glucose intolerance and characterized by the presence of two paralogs of the CMA-limiting factor Lamp2A (lysosomal associated membrane protein 2A). To this end, we validated a fluorescent reporter (KFERQ-PA-mCherry1) previously used to track functional CMA in mammalian cells, in an RT hepatoma-derived cell line (RTH-149). We found that incubation of cells with high-glucose levels (HG, 25 mM) induced translocation of the CMA reporter to lysosomes and/or late endosomes in a KFERQ- and Lamp2A-dependent manner, as well as reduced its half-life compared to the control (5 mM), thus demonstrating increased CMA flux. Furthermore, we observed that activation of CMA upon HG exposure was mediated by generation of mitochondrial reactive oxygen species, and involving the antioxidant transcription factor Nfe2l2/Nrf2 (nfe2 like bZIP transcription factor 2). Finally, we demonstrated that CMA plays an important protective role against HG-induced stress, primarily mediated by one of the two RT Lamp2As. Together, our results provide unequivocal evidence for CMA activity existence in RT and highlight both the role and regulation of CMA during glucose-related metabolic disorders. Abbreviations : AREs: antioxidant response elements; CHC: α-cyano -4-hydroxycinnamic acid; Chr: chromosome; CMA: chaperone-mediated autophagy; CT: control; DMF: dimethyl fumarate; Emi: endosomal microautophagy; HG: high-glucose; HMOX1: heme oxygenase 1; H 2 O 2 : hydrogen peroxide; KFERQ: lysine-phenylalanine-glutamate-arginine-glutamine; LAMP1: lysosomal associated membrane protein 1; LAMP2A: lysosomal associated membrane protein 2A; MCC: Manders' correlation coefficient; Manders' correlation coefficient Mo: morpholino oligonucleotide; NAC: N-acetyl cysteine; NFE2L2/NRF2: NFE2 like bZIP transcription factor 2; PA-mCherry: photoactivable mCherry; PCC: Pearson's correlation coefficient; ROS: reactive oxygen species; RT: rainbow trout; siRNAs: small interfering RNAs; SOD: superoxide dismutase; Tsg101: tumor susceptibility 101; TTFA: 2-thenoyltrifluoroacetone; WGD: whole-genome duplication. more...

Developing modulatory antibodies against G protein-coupled receptors is challenging. In this study, we targeted the follicle-stimulating hormone receptor (FSHR), a significant regulator of reproduction, with variable domains of heavy chain-only antibodies (VHHs). We built two immune VHH libraries and submitted them to multiplexed phage display approaches. We used next-generation sequencing to identify 34 clusters of specifically enriched sequences that were functionally assessed in a primary screen based on a cAMP response element (CRE)-dependent reporter gene assay. In this assay, 23 VHHs displayed negative or positive modulation of FSH-induced responses, suggesting a high success rate of the multiplexed strategy. We then focused on the largest cluster identified (i.e., PRC1) that displayed positive modulation of FSH action. We demonstrated that PRC1 specifically binds to the human FSHR and human FSHR/FSH complex while potentiating FSH-induced cAMP production and Gs recruitment. We conclude that the improved selection strategy reported here is effective for rapidly identifying functionally active VHHs and could be adapted to target other challenging membrane receptors. This study also led to the identification of PRC1, the first potential positive modulator VHH reported for the human FSHR. more...

The replacement of fishmeal by plant proteins in aquafeeds imposes the use of synthetic methionine (MET) sources to balance the amino acid composition of alternative diets and so to meet the metabolic needs of fish of agronomic interest such as rainbow trout (RT- Oncorhynchus mykiss ). Nonetheless, debates still exist to determine if one MET source is more efficiently used than another by fish. To address this question, the use of fish cell lines appeared a convenient strategy, since it allowed to perfectly control cell growing conditions notably by fully depleting MET from the media and studying which MET source is capable to restore cell growth/proliferation and metabolism when supplemented back. Thus, results of cell proliferation assays, Western blots, RT-qPCR and liquid chromatography analyses from two RT liver-derived cell lines revealed a better absorption and metabolization of DL-MET than DL-Methionine Hydroxy Analog (MHA) with the activation of the mechanistic Target Of Rapamycin (mTOR) pathway for DL-MET and the activation of integrated stress response (ISR) pathway for MHA. Altogether, the results clearly allow to conclude that both synthetic MET sources are not biologically equivalent, suggesting similar in vivo effects in RT liver and, therefore, questioning the MHA efficiencies in other RT tissues. more...

Ankyrin proteins (ANKRD) are key mediators linking membrane and sub-membranous cytoskeletal proteins. Recent findings have highlighted a new role of ANKRD31 during spermatogenesis, elucidating its involvement in meiotic recombination and male germ cell progression. Following testicular differentiation, spermatozoa (SPZ) enter into the epididymis, where they undergo several biochemical and enzymatic changes. The epididymal epithelium is characterized by cell-to-cell junctions that are able to form the blood-epididymal barrier (BEB). This intricate epithelial structure provides the optimal microenvironment needed for epididymal sperm maturation. To date, no notions have been reported regarding a putative role of ANKRD31 in correct BEB formation. In our work, we generated an Ankrd31 knockout male mouse model ( Ankrd31 -/- ) and characterized its reproductive phenotype. Ankrd31 -/- mice were infertile and exhibited oligo-astheno-teratozoospermia (a low number of immotile SPZ with abnormal morphological features). In addition, a complete deregulation of BEB was found in Ankrd31 -/- , due to cell-to-cell junction anomalies. In order to suggest that BEB deregulation may depend on Ankrd31 gene deletion, we showed the physical interaction among ANKRD31 and some epithelial junction proteins in wild-type (WT) epididymides. In conclusion, the current work shows a key role of ANKRD31 in the control of germ cell progression as well as sperm and epididymal integrity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Manfrevola, Martinez, Coutton, Rocco, Reynaud, Le Vern, Froment, Beauclair, Aubert, Pierantoni, Chianese and Guillou.) more...

Setmar is a gene specific to simian genomes. The function(s) of its isoforms are poorly understood and their existence in healthy tissues remains to be validated. Here we profiled SETMAR expression and its genome-wide binding landscape in colon tissue. We found isoforms V3 and V6 in healthy and tumour colon tissues as well as incell lines. In two colorectal cell lines SETMAR binds to several thousand Hsmar1 and MADE1 terminal ends, transposons mostly located in non-genic regions of active chromatin including in enhancers. It also binds to a 12-bp motifs similar to an inner motif in Hsmar1 and MADE1 terminal ends. This motif is interspersed throughout the genome and is enriched in GC-rich regions as well as in CpG islands that contain constitutive replication origins. It is also found in enhancers other than those associated with Hsmar1 and MADE1. The role of SETMAR in the expression of genes, DNA replication and in DNA repair are discussed., (Copyright © 2021 Elsevier Inc. All rights reserved.) more...

PiggyBac(PB)-like elements (pble) are members of a eukaryotic DNA transposon family. This family is of interest to evolutionary genomics because pble transposases have been domesticated at least 9 times in vertebrates. The amino acid sequence of pble transposases can be split into three regions: an acidic N-terminal domain (~100 aa), a central domain (~400 aa) containing a DD[D/E] catalytic triad, and a cysteine-rich domain (CRD; ~90 aa). Two recent reports suggested that a functional CRD is required for pble transposase activity. Here we found that two CRD-deficient pble transposases, a PB variant and an isoform encoded by the domesticated PB-derived vertebrate transposase gene 5 (pgbd5) trigger transposition of the Ifp2 pble. When overexpressed in HeLa cells, these CRD-deficient transposases can insert Ifp2 elements with proper and improper transposon ends, associated with deleterious effects on cells. Finally, we found that mouse CRD-deficient transposase Pgbd5, as well as PB, do not insert pbles at random into chromosomes. Transposition events occurred more often in genic regions, in the neighbourhood of the transcription start sites and were often found in genes predominantly expressed in the human central nervous system., (Copyright © 2021 Elsevier Ltd. All rights reserved.) more...

The vertebrate piggyBac derived transposase 5 (PGBD5) encodes a domesticated transposase, which is active and able to transpose its distantly related piggyBac-like element (pble), Ifp2. This raised the question whether PGBD5 would be more effective at mobilizing a phylogenetically closely related pble element. We aimed to identify the pble most closely related to the pgbd5 gene. We updated the landscape of vertebrate pgbd genes to develop efficient filters and identify the most closely related pble to each of these genes. We found that Tcr-pble is phylogenetically the closest pble to the pgbd5 gene. Furthermore, we evaluated the capacity of two murine and human PGBD5 isoforms, Mm523 and Hs524, to transpose both Tcr-pble and Ifp2 elements. We found that both pbles could be transposed by Mm523 with similar efficiency. However, integrations of both pbles occurred through both proper transposition and improper PGBD5-dependent recombination. This suggested that the ability of PGBD5 to bind both pbles may not be based on the primary sequence of element ends, but may involve recognition of inner DNA motifs, possibly related to palindromic repeats. In agreement with this hypothesis, we identified internal palindromic repeats near the end of 24 pble sequences, which display distinct sequences., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.) more...

Efforts to elucidate the causes of biological differences between wild fowls and their domesticated relatives, the chicken, have to date mainly focused on the identification of single nucleotide mutations. Other types of genomic variations have however been demonstrated to be important in avian evolution and associated to variations in phenotype. They include several types of sequences duplicated in tandem that can vary in their repetition number. Here we report on genome size differences between the red jungle fowl and several domestic chicken breeds and selected lines. Sequences duplicated in tandem such as rDNA, telomere repeats, satellite DNA and segmental duplications were found to have been significantly re-shaped during domestication and subsequently by human-mediated selection. We discuss the extent to which changes in genome organization that occurred during domestication agree with the hypothesis that domesticated animal genomes have been shaped by evolutionary forces aiming to adapt them to anthropized environments., (Copyright © 2019 Elsevier Inc. All rights reserved.) more...

Background: More and more eukaryotic genomes are sequenced and assembled, most of them presented as a complete model in which missing chromosomal regions are filled by Ns and where a few chromosomes may be lacking. Avian genomes often contain sequences with high GC content, which has been hypothesized to be at the origin of many missing sequences in these genomes. We investigated features of these missing sequences to discover why some may not have been integrated into genomic libraries and/or sequenced., Results: The sequences of five red jungle fowl cDNA models with high GC content were used as queries to search publicly available datasets of Illumina and Pacbio sequencing reads. These were used to reconstruct the leptin, TNFα, MRPL52, PCP2 and PET100 genes, all of which are absent from the red jungle fowl genome model. These gene sequences displayed elevated GC contents, had intron sizes that were sometimes larger than non-avian orthologues, and had non-coding regions that contained numerous tandem and inverted repeat sequences with motifs able to assemble into stable G-quadruplexes and intrastrand dyadic structures. Our results suggest that Illumina technology was unable to sequence the non-coding regions of these genes. On the other hand, PacBio technology was able to sequence these regions, but with dramatically lower efficiency than would typically be expected., Conclusions: High GC content was not the principal reason why numerous GC-rich regions of avian genomes are missing from genome assembly models. Instead, it is the presence of tandem repeats containing motifs capable of assembling into very stable secondary structures that is likely responsible. more...

Transposable elements are driving forces for establishing genetic innovations such as transcriptional regulatory networks in eukaryotic genomes. Here, we describe a silencer situated in the last 300 bp of the Mos1 transposase open reading frame (ORF) which functions in vertebrate and arthropod cells. Functional silencers are also found at similar locations within three other animal mariner elements, i.e. IS630-Tc1-mariner (ITm) DD34D elements, Himar1, Hsmar1 and Mcmar1. These silencers are able to impact eukaryotic promoters monitoring strong, moderate or low expression as well as those of mariner elements located upstream of the transposase ORF. We report that the silencing involves at least two transcription factors (TFs) that are conserved within animal species, NFAT-5 and Alx1. These cooperatively act with YY1 to trigger the silencing activity. Four other housekeeping transcription factors (TFs), neuron restrictive silencer factor (NRSF), GAGA factor (GAF) and GTGT factor (GTF), were also found to have binding sites within mariner silencers but their impact in modulating the silencer activity remains to be further specified. Interestingly, an NRSF binding site was found to overlap a 30 bp motif coding a highly conserved PHxxYSPDLAPxD peptide in mariner transposases. We also present experimental evidence that silencing is mainly achieved by co-opting the host Polycomb Repressive Complex 2 pathway. However, we observe that when PRC2 is impaired another host silencing pathway potentially takes over to maintain weak silencer activity. Mariner silencers harbour features of Polycomb Response Elements, which are probably a way for mariner elements to self-repress their transcription and mobility in somatic and germinal cells when the required TFs are expressed. At the evolutionary scale, mariner elements, through their exaptation, might have been a source of silencers playing a role in the chromatin configuration in eukaryotic genomes. more...

Background: Physicians have prescribed anticholinergic agents such as benztropine, procyclidine, biperiden and trihexyphenidyl for treatment and prophylaxis of antipsychotic-induced extrapyramidal symptoms (EPS) for decades. Anticholinergic agents can however worsen tardive dyskinesia and cause many adverse effects, including cognitive impairment. Previous studies of anticholinergic discontinuation in patients with schizophrenia receiving antipsychotics have yielded a wide range of EPS relapse rates. Improvement in cognition after anticholinergic withdrawal was observed in some studies., Objective: This study evaluated the effect of anticholinergic discontinuation on movement disorders, cognition and general psychopathology after a 4-week taper in 20 outpatients with schizophrenia or schizoaffective disorder treated with antipsychotics., Results: Eighteen of twenty patients successfully discontinued their anticholinergic medication; two did not because of akathisia. Repeated measures analysis of variance did not show a significant effect of anticholinergic discontinuation on total Extrapyramidal Symptoms Rating Scale score or on the Parkinsonism, Akathisia, Dystonia or Tardive Dyskinesia subscales. However, significant improvement was found on the Brief Assessment of Cognition in Schizophrenia composite z score at weeks 6, 8 and 12 compared with baseline. Significant improvements were seen on the motor and the symbol-coding tasks. No significant effects were observed on the Positive and Negative Syndrome Scale, Clinical Global Impression - Severity and Clinical Global Impression - Improvement scales., Conclusion: In this 12-week study of anticholinergic discontinuation in 20 outpatients with schizophrenia or schizoaffective disorder, gradual decrease and discontinuation of anticholinergics led to a positive effect on cognition. There were no adverse consequences on general psychopathology and no significant differences for 18 of 20 subjects on movement disorders. more...

Plant microRNAs (miRNAs) typically form near-perfect duplexes with their targets and mediate mRNA cleavage. Here, we describe an unconventional miRNA target of miR398 in Arabidopsis, an mRNA encoding the blue copper-binding protein (BCBP). BCBP mRNA carries an miR398 complementary site in its 5'-untranslated region (UTR) with a bulge of six nucleotides opposite to the 5' region of the miRNA. Despite the disruption of a target site region thought to be especially critical for function, BCBP mRNAs are cleaved by ARGONAUTE1 between nucleotides 10th and 11th, opposite to the miRNA, like conventional plant target sites. Levels of BCBP mRNAs are inversely correlated to levels of miR398 in mutants lacking the miRNA, or transgenic plants overexpressing it. Introducing two mutations that disrupt the miRNA complementarity around the cleavage site renders the target cleavage-resistant. The BCBP site functions outside of the context of the BCBP mRNA and does not depend on 5'-UTR location. Reducing the bulge does not interfere with miR398-mediated regulation and completely removing it increases the efficiency of the slicing. Analysis of degradome data and target predictions revealed that the miR398-BCBP interaction seems to be rather unique. Nevertheless, our results imply that functional target sites with non-perfect pairings in the 5' region of an ancient conserved miRNA exist in plants. more...

Objective: To assess outcomes over 24 months in Canadian patients with schizophrenia initiated on risperidone long-acting injection (RLAI) and participating in the electronic Schizophrenia Treatment Adherence Registry (e-STAR)., Materials and Methods: Patients with schizophrenia or schizoaffective disorder were enrolled from 24 sites after an independent decision to initiate RLAI. Subsequent patient management was based on usual clinical practice at each site and was not protocol-driven. Relevant data were collected retrospectively by chart review for 12 months prior to RLAI and prospectively for 24 months following RLAI initiation., Results: Patients (n=188) had a mean age of 39.2 years, were 66.3% male, and 27.7% were inpatients at baseline. Twenty-four months after initiating therapy (initial dose =28.7 mg), 34.1% (95% confidence interval 27.2%-42.2%) of patients had discontinued RLAI with a mean time to discontinuation of 273.4±196 days. Over the treatment period, there were significant (P<0.001) changes from baseline in Clinical Global Impression-Severity (CGI-S; 3.48 versus [vs] 4.31 at baseline), Global Assessment of Functioning (GAF; 56.1 vs 48.1), and Personal and Social Performance (PSP; 59.1 vs 46.9) scale scores. In addition, after 12 months, there were significant (P<0.001) decreases in the percentage of patients hospitalized (23.9% vs 58.5% pre-RLAI), mean length of stay (11.4 vs 30.4 days), and number of hospitalizations (0.32 vs 0.87) compared to the 12-month pre-RLAI period. Reductions in hospitalization continued into the second 12 months of therapy, when only 9% of patients were hospitalized and mean length of stay was 2.0 days., Conclusion: In a routine clinical practice setting, patients switched to RLAI showed significant improvements in clinical outcomes and in global and social functioning, and hospitalization was significantly reduced. The data confirm that RLAI provides effective long-term management of schizophrenia in Canada. more...

Anticholinergic agents are usually prescribed to prevent or treat antipsychotic-induced extrapyramidal symptoms. Their long-term benefits are questionable and they carry diverse adverse effects, including cognitive impairment and worsening of tardive dyskinesia. This literature review explores the impact of anticholinergic medication discontinuation on movement disorders, cognition and psychopathology in patients receiving antipsychotics. Medline, Embase and PsycInfo were searched from 1950 to July 2011 using "cessation /withdrawal /discontinuation /stopping" with "anticholinergic*" or "antiparkinson*" and "neuroleptic*" or "antipsychotic*". Additional articles were obtained by searching the bibliographies of relevant references. Earlier studies of anticholinergic agent discontinuation in patients receiving first-generation antipsychotics reported relapse rates of extrapyramidal symptoms between 4% and 80%, reflecting the heterogeneity of the studies. Two recent studies of patients prescribed second-generation antipsychotics obtained relapse rates of 4% and 33%. Some studies suggest improvement in tardive dyskinesia with cessation of anticholinergics. Four studies examined the effects of anticholinergic agent discontinuation on cognition and all observed an improvement post-discontinuation. Changes in symptoms of schizophrenia with anticholinergic discontinuation are conflicting, with more recent studies suggesting an improvement. Given their questionable benefit with continued use, clinicians should consider a gradual withdrawal of anticholinergic agents in stable patients receiving antipsychotics. more...

Generic medications do not undergo the rigorous approval process required of original medications. Their effectiveness and safety is expected to be equal to that of their more expensive counterparts. However, several case reports and studies describe clinical deterioration and decreased tolerability with generic substitution. Pubmed was searched from January 1, 1974 to March 1, 2010. The MeSH term "generic, drugs" was combined with "anticonvulsants," "mood stabilizers," "lithium," "antidepressants," "antipsychotics," "anxiolytics," and "benzodiazepines." Additional articles were obtained by searching the bibliographies of relevant references. Articles in English, French, or Spanish were considered if they discussed clinical equivalence of generic and brand-name medications, generic substitution, or issues about effectiveness, tolerability, compliance, or economics encountered with generics. Clinical deterioration, adverse effects, and changes in pharmacokinetics are described with generic substitution of several anticonvulsants/mood stabilizers (carbamazepine, valproate, lamotrigine, gabapentin, topiramate, lithium), antidepressants (amitriptyline, nortriptyline, desipramine, fluoxetine, paroxetine, citalopram, sertraline, venlafaxine, mirtazapine, bupropion), antipsychotics (risperidone, clozapine), and anxiolytics (clonazepam, alprazolam). Generics do not always lead to the anticipated monetary savings and also raise compliance issues. Although the review is limited by publication bias and heterogeneity of the studies in the literature, we believe there is enough concern to advise generic switching on an individual basis with close monitoring throughout the transition. Health professionals should be aware of the stakes around generic substitution especially when health economics promote universal use of generics., (© 2010 Blackwell Publishing Ltd.) more...

microRNA398 (miR398) is a conserved miRNA of plants that targets two of the three copper/zinc superoxide dismutases (SOD) of Arabidopsis (CSD1 and CSD2) by triggering cleavage or inhibiting translation of their mRNAs. We analysed the transcriptomes of mutants impaired in miR398 production, and found that the mRNAs encoding the copper chaperone for superoxide dismutase (CCS1), which delivers copper to CSD1 and CSD2 apoproteins in different cellular compartments, are undiscovered targets of miR398. We identified the cleavage site in CCS1 mRNAs by 5'-RACE PCR. We further show that both CCS1 protein and mRNA levels are tightly linked to the quantities of miR398, which are themselves dependent on the copper content in the medium. We generated transgenic plants carrying a CCS1 mRNA version resistant to cleavage by miR398, and demonstrated that both CCS1 mRNAs and proteins accumulate in these plants when miR398 is abundant and copper limiting. Moreover, we show that one of the ten ARGONAUTE proteins of Arabidopsis (AGO10) is involved in miR398-directed translational inhibition of CCS1 mRNAs, as CCS1 protein, but not CCS1 mRNAs accumulates in ago10 (zll) mutants. Thus, miR398 mediates the cleavage and translational inhibition of mRNAs encoding CCS1, the chaperone protein that is essential for generating the mature copper/zinc SODs of Arabidopsis. Our results also imply that new targets that have not been identified by computing analyses have yet to be discovered, even for an extensively studied miRNA such as miR398. more...

Generic formulations of medications are marketed as therapeutically equivalent and less expensive than branded ones. Multiple studies and case reports have described relapses and worsening clinical outcome in patients after a switch from a brand name to a generic medication. Recent studies have shown that generics do not always lead to the expected costs savings, reducing the impetus to proceed with compulsory generic switching. We report on three patients who experienced clinical deterioration after commencing the generic formulation of their previous brand name psychotropic medication. We discuss key clinical differences between original and generic formulations of the same medication. The use of bioequivalence as an indicator of therapeutic and clinical equivalence, the lack of appropriate studies comparing generic and brand name medications and differences in excipients are some of the factors that could explain variation in clinical response between generic and brand name medications. Generic switching should be decided on a case-by-case basis with disclosure of potential consequences to the patient. more...

Long terminal repeat (LTR) retrotransposons are generally silent in plant genomes. However, they often constitute a large proportion of repeated sequences in plants. This suggests that their silencing is set up after a certain copy number is reached and/or that it can be released in some circumstances. We introduced the tobacco (Nicotiana tabacum) LTR retrotransposon Tnt1 into Arabidopsis (Arabidopsis thaliana), thus mimicking the horizontal transfer of a retrotransposon into a new host species and allowing us to study the regulatory mechanisms controlling its amplification. Tnt1 is transcriptionally silenced in Arabidopsis in a copy number-dependent manner. This silencing is associated with 24-nucleotide short-interfering RNAs targeting the promoter localized in the LTR region and with the non-CG site methylation of these sequences. Consequently, the silencing of Tnt1 is not released in methyltransferase1 mutants, in contrast to decrease in DNA methylation1 or polymerase IVa mutants. Stable reversion of Tnt1 silencing is obtained when the number of Tnt1 elements is reduced to two by genetic segregation. Our results support a model in which Tnt1 silencing in Arabidopsis occurs via an RNA-directed DNA methylation process. We further show that silencing can be partially overcome by some stresses. more...

Background: The gamma-aminubutyrate (GABA) shunt bypasses two steps of the tricarboxylic acid cycle, and is present in both prokaryotes and eukaryotes. In plants, the pathway is composed of the calcium/calmodulin-regulated cytosolic enzyme glutamate decarboxylase (GAD), the mitochondrial enzymes GABA transaminase (GABA-T; POP2) and succinic semialdehyde dehydrogenase (SSADH). We have previously shown that compromising the function of the GABA-shunt, by disrupting the SSADH gene of Arabidopsis, causes enhanced accumulation of reactive oxygen intermediates (ROIs) and cell death in response to light and heat stress. However, to date, genetic investigations of the relationships between enzymes of the GABA shunt have not been reported., Principal Findings: To elucidate the role of succinic semialdehyde (SSA), gamma-hydroxybutyrate (GHB) and GABA in the accumulation of ROIs, we combined two genetic approaches to suppress the severe phenotype of ssadh mutants. Analysis of double pop2 ssadh mutants revealed that pop2 is epistatic to ssadh. Moreover, we isolated EMS-generated mutants suppressing the phenotype of ssadh revealing two new pop2 alleles. By measuring thermoluminescence at high temperature, the peroxide contents of ssadh and pop2 mutants were evaluated, showing that only ssadh plants accumulate peroxides. In addition, pop2 ssadh seedlings are more sensitive to exogenous SSA or GHB relative to wild type, because GHB and/or SSA accumulate in these plants., Significance: We conclude that the lack of supply of succinate and NADH to the TCA cycle is not responsible for the oxidative stress and growth retardations of ssadh mutants. Rather, we suggest that the accumulation of SSA, GHB, or both, produced downstream of the GABA-T transamination step, is toxic to the plants, resulting in high ROI levels and impaired development. more...

Objective: Tardive dyskinesia (TD), the principal adverse effect of long-term conventional antipsychotic treatment, can be debilitating and, in many cases, persistent. We sought to explore the incidence and management of TD in the era of atypical antipsychotics because it remains an important iatrogenic adverse effect., Methods: We conducted a review of TD incidence and management literature from January 1, 1965, to January 31, 2004, using the terms tardive dyskinesia, management, therapy, neuroleptics, antipsychotics, clozapine, olanzapine, risperidone, quetiapine, ziprasidone, and aripiprazole. Additional articles were obtained by searching the bibliographies of relevant references. We considered articles that contributed to the current understanding of both the incidence of TD with atypical antipsychotics and management strategies for TD., Results: The incidence of TD is significantly lower with atypical, compared with typical, antipsychotics, but cases of de novo TD have been identified. Evidence suggests that atypical antipsychotic therapy ameliorates long-standing TD. This paper outlines management strategies for TD in patients with schizophrenia., Conclusion: The literature supports the recommendation that atypical antipsychotics should be the first antipsychotics used in patients who have experienced TD as a result of treatment with conventional antipsychotic agents. The other management strategies discussed may prove useful in certain patients. more...

Objective: Tardive dyskinesia (TD) is the principal adverse effect of long-term treatment with conventional antipsychotic agents. Several mechanisms may exist for this phenomenon. Mechanisms for the lower incidence of TD with atypical antipsychotics also remain to be fully understood. We undertook to explore and better understand these mechanisms., Methods: We conducted a comprehensive review of TD pathophysiology literature from January 1, 1965, to January 31, 2004, using the terms tardive dyskinesia, neuroleptics, antipsychotics, pathophysiology, and mechanisms. Additional articles were obtained by searching the bibliographies of relevant references. Articles were considered if they contributed to the current understanding of the pathophysiology of TD., Results: Current TD vulnerability models include genetic vulnerability, disease-related vulnerability, and decreased functional reserve. Mechanisms of TD induction include prolonged blockade of postsynaptic dopamine receptors, postsynaptic dopamine hypersensitivity, damage to striatal GABA interneurons, and damage of striatal cholinergic interneurons. Atypical antipsychotics may cause less TD because they have less impact on the basal ganglia and are less likely to cause postsynaptic dopamine hypersensitivity., Conclusion: Although the ultimate model for TD is not yet understood, it is plausible that several of these vulnerabilities and mechanisms act together to produce TD. The lower incidence of TD with atypical antipsychotics has helped to elucidate the,mechanisms of TD. more...

A 3-year open-label study was conducted to determine the long-term safety and efficacy of quetiapine monotherapy in schizophrenia and schizoaffective disorder.Twenty-three male outpatients previously stable but with inter-episode residual symptoms on classical antipsychotics and/or risperidone and who had complained of side effects were selected. To initiate quetiapine, patients were hospitalized for 13 days and then treated as outpatients. Quetiapine dosage was adjusted according to therapeutic effects. Only five patients (21.7%) completed 77 to 96 weeks of the study. Initial dose was 261 +/- 65.6 mg/day (mean +/- S.D.) administered in divided doses, with an ending dose of 487 +/- 209.6 mg/day, corresponding with an 86.6% dose increase over the course of the study. For those completing 12 weeks or less (n = 11), mean ending dose was 362 +/- 184.8 mg/day a 38.7% dose increase over baseline. For those completing 25 weeks or more (n = 12), mean ending dose was 592 +/- 178.2 mg/day, a 126.8% dose increase over baseline. Six of the seven patients who relapsed after being stabilized on quetiapine for at least three months met criteria for supersensitivity psychosis (SSP).Therapeutic tolerance and rebound psychosis were found to develop with quetiapine in male patients with a history of chronic treatment with classical antipsychotics. Seeman and Tallerico3 have proposed pharmacologic explanations for quetiapine and clozapine drug-induced rebound phenomena. more...

The effectiveness of selective serotonin reuptake inhibitors for depression in remitted schizophrenia has not been clearly demonstrated. A randomized, double-blind, prospective placebo-controlled study was performed of 48 subjects meeting DSM-IV criteria for both schizophrenia in remission and for a major depressive episode. Twenty-seven patients were randomized to placebo and 21 to sertraline. All subjects had a 1-week anticholinergic phase before randomization. The treatment duration was 6 weeks. Sertraline was started at 50 mg/day; this could be increased to 100 mg after 4 weeks for an inadequate response. There were no statistically significant differences in symptoms between the two groups at randomization. There were no differences in outcome between treatment groups. In both groups, between 40% and 50% of subjects showed a 50% reduction in depression score. This study does not provide support for the efficacy of sertraline in the treatment of depression in remitted schizophrenia. The small sample size limits the strength of the conclusions that can be drawn from this study. The study design called for a sample size of 96 on the basis of an expected placebo response rate of 30%. Recruitment for the study was difficult because of the placebo design. The placebo response was 50%. Clinicians and patients underestimate the strength of the placebo response and may overestimate the risk of participating in such a study. Testing the efficacy of widely accepted but poorly evaluated treatments should be a research priority. Future studies require a larger sample size and longer duration of treatment. more...

The objective of the present study was to compare the safety and efficacy of moclobemide versus fluoxetine in adult patients with major depressive disorder. The design of the study was a multicenter, double-blind, comparative, and randomized trial. A 1- to 2-week single-blind placebo washout phase was followed by 6 weeks of double-blind treatment with moclobemide or fluoxetine. A total of 150 patients were enrolled in the study. There were 128 patients eligible to be randomized, with 66 patients receiving moclobemide and 62 patients receiving fluoxetine. At the termination of the study, patients in the moclobemide group were receiving a mean dose of 440 mg +/- 123 mg, while the mean dose in the fluoxetine group was 35 mg +/- 8 mg. No significant treatment differences were found for any of the efficacy parameters. Headache and nausea were the most frequently reported adverse events in both treatment groups. Headache and blurred vision were reported significantly more often (P < 0.05) in the fluoxetine group, whereas significantly more dry mouth was reported (P < 0.05) in the moclobemide group. These results provide supporting evidence of the comparable efficacy of moclobemide and fluoxetine and the better tolerability of moclobemide when used in the treatment of major depressive disorder. more...

We carried out a 9-day double-blind clinical trial comparing intramuscular zuclopenthixol acetate with liquid oral haloperidol in the treatment of 40 newly admitted schizophrenic patients with acute exacerbation. A parallel-group design was used with stratification by sex. Zuclopenthixol acetate (50 to 150 mg) was given intramuscularly every 3 days, whereas liquid haloperidol (10 to 30 mg daily) was given orally three times a day, with supplementary doses of each medication given under double-blind conditions when needed for agitation. No other sedative drugs, including benzodiazepines, were administered. The mean daily dose was 18.9 mg for haloperidol as compared with a mean dose per 3 days of 117.6 mg for zuclopenthixol. The two treatments were found to be equally efficacious on the Brief Psychiatric Rating Scale and Clinical Global Impression Scale. Both drugs induced similar extrapyramidal side effects. However, more tremors were associated with zuclopenthixol as was a tendency for tardive dyskinesia to be unmasked at the end of the injection interval. Sedation was higher with zuclopenthixol acetate than with haloperidol. Serum creatinine phosphokinase levels were not significantly increased after zuclopenthixol injections. The results of this trial suggest that zuclopenthixol acetate given intramuscularly every second to third day offers an alternative to conventional liquid oral haloperidol in the management of acute schizophrenia. more...

Thirty-two outpatients with a DSM-III diagnosis of panic disorder or agoraphobia with panic attacks were randomly assigned to 4 weeks of treatment with clonazepam or placebo, after a 1-week placebo washout period. Twenty-nine patients entered the double-blind phase of the study and were eligible for intent-to-treat analysis. Clonazepam-treated patients experienced significantly fewer panic attacks, and these were of lesser intensity and short duration than those in placebo-treated patients (p < 0.001). Clonazepam was also superior to placebo with respect to symptoms of anxiety and depression (p < 0.001). The mean dose of clonazepam at week 4 was 2.2 mg (standard deviation, 0.7 mg). There was significant (p < 0.05) correlation between drug concentration in plasma and decrease in the global measure of the severity of panic disorder (r = 0.68); similar trends were seen for the decreases in frequency (r = 0.60) and severity (r = 0.55) of panic attacks, but not between concentration in plasma and decline in generalized anxiety. The most common adverse event was drowsiness, which occurred in 9 of 13 clonazepam-treated patients. more...

In a double-blind study, 135 inpatients with a diagnosis of chronic schizophrenia were randomly assigned to 8 weeks of treatment with one of six parallel treatments: risperidone (a new central 5-hydroxytryptamine2 and dopamine D2 antagonist), 2, 6, 10, 16 mg/day; haloperidol, 20 mg/day; or placebo, after a single-blind placebo washout period. Doses were increased in fixed increments up to a fixed maintenance dose reached after 1 week. On the Clinical Global Impression-Severity of Illness and Improvement, all active medications were superior to placebo except for risperidone (2 mg) on the Clinical Global Impression-Improvement. On the total Positive and Negative Syndrome Scale (PANSS) score and positive subscale, superiority to placebo was observed for all treatment groups except for haloperidol and risperidone (2 mg), which tended to be superior to placebo on total PANSS and the positive subscale, respectively. On the PANSS negative subscale, only risperidone (6 mg/day) was significantly better than placebo. Risperidone (6 mg) was superior to haloperidol on the total PANSS, General Psychopathology, and Brief Psychiatric Rating Scale subscales. Although there was a linear increase in parkinsonism with increasing risperidone dosage, there were no statistically significant differences between risperidone (2, 6, and 16 mg/day) and placebo. At doses of 6 to 16 mg, risperidone displayed a marked antidyskinetic effect compared with placebo. This effect was more pronounced in patients with severe dyskinesia. By contrast, haloperidol produced significantly more parkinsonism than placebo and risperidone (2, 6 and 16 mg), with no effect on tardive dyskinesia. These data suggest that risperidone, at the optimal therapeutic dose of 6 mg/day, produced significant improvement in both positive and negative symptoms without an increase in drug-induced parkinsonian symptoms and with a significant beneficial effect on tardive dyskinesia. more...

In a double-blind placebo-controlled study, following a 1 week washout, 75 outpatients suffering from generalized anxiety disorder with severe insomnia as the target symptom were randomly assigned to 4 weeks of treatment with zopiclone 7.5 mg, triazolam 0.5 mg or placebo at bedtime. Zopiclone was significantly better than placebo on most sleep parameters. Triazolam tended to be superior to placebo, but its superiority was significant only on the sleep induction factor. Triazolam-treated patients presented significantly more day-time-interdose anxiety than zopiclone as assessed by the weekly HARS and Clinical Global Assessment of Anxiety. Although daytime-interdose anxiety was observed with both drugs, this treatment emergent symptom was more frequent and severe with triazolam. Side-effects were of a mild to moderate intensity for both zopiclone and triazolam; however, taste perversion frequently appeared with zopiclone. Although both drugs share similar pharmacological properties and bind to benzodiazepine receptors, they differ significantly with respect to side-effects and daytime anxiety. more...

Valproic acid (VA), an anticonvulsant which increases GABAergic transmission was given to patients suffering from recurrent panic attacks. Ten consecutive outpatients were included in this study. After a seven day placebo washout period, patients were given a dose of 500 mg/day, which was gradually increased to a maximum of 2250 mg/day. A significant improvement was found in the symptomatology of patients as measured on the Clinical Global Impression Scale for panic severity (p less than 0.001), the Hamilton Psychiatric Rating Scale for Anxiety (p less than 0.001) and the panic factor of the SCL-90 (p less than 0.05). These findings support the hypothesis that VA is useful in the treatment of panic disorders. Further research should be carried out to assess its efficacy and safety. more...

1. Nine severe rapid cycling manic-depressive patients were treated with a magnesium preparation, Magnesiocard 40 mEq/day in an open label study for a period up to 32 weeks. 2. Magnesiocard was found to have clinical results at least equivalent to those of lithium in about 50% of these patients. These results were obtained in an exploratory study and should be interpreted with caution. 3. The possibility that Magnesiocard could replace or improve the efficacy of lithium as a preventive treatment of manic-depressive illness merits further clinical investigation. more...