Climate change negative effects on the Neotropical fishery resources may be exacerbated by hydroelectric dams

Climate change is now recognized as a reality and along with human pressures such as river fragmentation by dams, amplifies the threats to freshwater ecosystems and their biodiversity. In the Brazilian portion of the Upper Paraguay River Basin (UPRB) that encompasses the Pantanal, one of the largest tropical wetlands in the world, in addition to the high biodiversity found there, fisheries are an important ecosystem service mostly supported by migratory fishes. We estimated the current range of migratory fish of commercial interest, also assessing the climate change effects predicted on the distribution patterns. Then, we assessed the effects of future climate on fish richness, and combining species ranges with routes blocked by artificial dams investigated possible impacts on fishery and food security in the UPRB. Climate change will induce range contraction between 47% and 100% for the species analyzed, and only four migratory fish may have suitable habitat until the end-of-century. The local richness will reduce about 85% in the basin. River fragmentation by dams acting together with climate change will prevent upstream shifts for most fish species. About 4% of present range and up to 45% of future range of migratory fish should be blocked by dams in UPRB. Consequently, this will also negatively affect fishery yield and food security in the future.

NEOTROPICAL FRESHWATER FISHES: A dataset of occurrence and abundance of freshwater fishes in the Neotropics

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications.

Coupling environment and physiology to predict effects of climate change on the taxonomic and functional diversity of fish assemblages in the Murray-Darling Basin, Australia

This study uses species distribution modeling and physiological and functional traits to predict the impacts of climate change on native freshwater fish in the Murray-Darling Basin, Australia. We modelled future changes in taxonomic and functional diversity in 2050 and 2080 for two scenarios of carbon emissions, identifying areas of great interest for conservation. Climatic-environmental variables were used to model the range of 23 species of native fish under each scenario. The consensus model, followed by the physiological filter of lethal temperature was retained for interpretation. Our study predicts a severe negative impact of climate change on both taxonomic and functional components of ichthyofauna of the Murray-Darling Basin. There was a predicted marked contraction of species ranges under both scenarios. The predictions showed loss of climatically suitable areas, species and functional characters. There was a decrease in areas with high values of functional richness, dispersion and uniqueness. Some traits are predicted to be extirpated, especially in the most pessimistic scenario. The climatic refuges for fish fauna are predicted to be in the southern portion of the basin, in the upper Murray catchment. Incorporating future predictions about the distribution of ichthyofauna in conservation management planning will enhance resilience to climate change.

Ichthyofauna from three streams of the lower Iguatemi River in the upper Paraná river basin, Brazil

The ichthyofauna from 3 streams (Água Boa, Perobão, and Santa Maria) to the lower Iguatemi River were inventoried, which is located in the upper Paraná river basin, in Mato Grosso do Sul state, Brazil. Sites in the upper, intermediate, and lower portions of each stream were quarterly electrofished from March to December 2008. All sampled fish (n = 6,816 individuals) represented 43 species of 5 orders, and 16 families. The most abundant species was Phalloceros harpagos (63.5%), followed by Astyanax aff. paranae (10.6%), Hypostomus ancistroides (5.9%), Gymnotus inaequilabiatus (3.4%), and Knodus moenkhausii (2.7%). Despite the high ichthyofauna richness in the lower portion of Iguatemi River, the need to implement and/or expand soil conservation practices and riparian forest restoration is of utmost importance to maintain these populations in the long term. 

Two sides of a coin: Effects of climate change on the native and non-native distribution of Colossoma macropomum in South America

Climate change and species invasions interact in nature, disrupting biological communities. Based on this knowledge, we simultaneously assessed the effects of climate change on the native distribution of the Amazonian fish Colossoma macropomum as well as on its invasiveness across river basins of South America, using ecological niche modeling. We used six niche models within the ensemble forecast context to predict the geographical distribution of C. macropomum for the present time, 2050 and 2080. Given that this species has been continuously introduced into non-native South American basins by fish farming activities, we added the locations of C. macropomum farms into the modeling process to obtain a more realistic scenario of its invasive potential. Based on modelling outputs we mapped climate refuge areas at different times. Our results showed that a plenty of climatically suitable areas for the occurrence of C. macropomum occurrence are located outside the original basins at the present time and that its invasive potential is greatly amplified by fish farms. Simulations of future geographic ranges revealed drastic range contraction in the native region, implying concerns not only with respect to the species conservation but also from a socio-economic perspective since the species is a cornerstone of artisanal and commercial fisheries in the Amazon. Although the invasive potential is projected to decrease in the face of climate change, climate refugia will concentrate in Paraná River, Southeast Atlantic and East Atlantic basins, putting intense, negative pressures on the native fish fauna these regions. Our findings show that short and long-term management actions are required for: i) the conservation of natural stocks of C. macropomum in the Amazon, and ii) protecting native fish fauna in the climate refuges of the invaded regions.

[The adolescent abstainers: A risk group?]

OBJECTIVE

If abstinence from substance in adolescents may nowadays be regarded statistically as a deviant behavior, what is its significance from a developmental point of view? The aim of this article is to examine the mental health characteristics and the social integration of adolescent abstainers.

METHODS

A comprehensive literature review of epidemiological studies including data on adolescent abstainers was conducted.

RESULTS

Compared to the abundant literature devoted to adolescent substance abusers, few studies report data on adolescent abstainers. In addition, many methodological problems limit their interpretability and their comparison. However that may be, this body of work suggests that if abstinence may be due to something intrinsic about the individual (such as psychosocial adjustment difficulties, personality traits or gender), many other environmental factors (such as family background of temperance, cultural practices, upbringing or religion) may determine abstaining behavior. By this way, from a psychopathological angle, adolescent abstainers certainly constitute a more heterogeneous group than the adolescent substance abusers. Some of them are quite psychologically healthy, whereas others are more socially withdrawn and may suffer from emotional disorders.

CONCLUSION

In terms of prevention, these data highlight the need for longitudinal prospective studies examining the psychosocial status of adolescent abstainers, their antecedents, their outcome and their motivations.

[Pharmacological treatment of bipolar disorder in children and adolescents]

OBJECTIVE

To review the options for acute and maintenance pharmacological treatment of bipolar disorder in children and adolescents.

METHODS

A comprehensive literature review of randomized clinical trials and open-label studies was conducted.

RESULTS

Published data from randomized controlled trials show that antipsychotics are significantly more effective than mood stabilizers in the treatment of manic or mixed episodes. Few data are available related to the treatment of depressive episodes. No trials of selective serotonin reuptake inhibitors have been conducted. Only open trials suggest that lithium and lamotrigine may be effective, whereas quetiapine did not demonstrate efficacy relative to placebo in two studies. Studies regarding the effectiveness of antipsychotics and mood stabilizers for the comorbid disorders are also few and inconclusive. Although long-term treatment is a core aspect of the management of children and adolescents with bipolar disorder, there is a lack of consistent efficacy data. If non-controlled trials suggest that lithium, lamotrigine, quetiapine, ziprazidone, and the combination of risperidone and divalproex or lithium may be useful in some conditions, only aripiprazole has shown efficacy relative to placebo for long-term symptom reduction and relapse prevention. Safety data show that the most frequently reported adverse events in children and adolescents treated with mood stabilizers are gastrointestinal and neurological, whereas use of antipsychotics is mainly related to weight gain and sedation. Lastly, while results from studies having evaluated the impact of pharmacological treatment on neuropsychological functioning are inconsistent, some of them nevertheless suggest that treatment with mood stabilizers may be associated with specific impairments.

CONCLUSION

Despite recent developments in identifying effective pharmacological interventions, numerous critical gaps remain.

First cytogenetic record for a species of Otothyropsis Ribeiro, Carvalho & Melo, 2005 (Loricariidae, Hypoptopomatinae)

ABTRACT Hypoptopomatinae is a monophyletic subfamily that includes 147 species, distributed in 20 genera. Otothyropsis is a genus of Hypoptopomatinae, recently described. Here, we provided the first cytogenetic information of Otothyropsis . The specimens were collected from córrego Dourado, a small tributary of rio Iguatemi, which flows into rio Paraná. The specimens of Otothyropsis cf. polyodon were analyzed with respect to diploid number, C-Band and Ag-NOR patterns. The diploid number was 54 chromosomes, distributed in 18 metacentric, 28 submetacentric, and 8 subtelocentric chromosomes, with single Ag-NOR and conspicuous heterochromatic blocks on the short and long arms of the 24th pair of chromosomes. Our study highlights the conservation trend of the diploid number (2n=54) and fundamental number (FN = 108) among the species of Hypoptopomatinae. However, the karyotype formula (18m+28sm+8st) seems to be specific to O. cf. polyodon , considering the other Hypoptopomatinae species already analyzed.

Assemblage of immature Odonata (Insecta, Anisoptera) in streams of the Mato Grosso do Sul State: spatial implications

ABSTRACT This study investigated the assemblages attributes (composition, abundance, richness, diversity and evenness) and the most representative genera of Odonata, Anisoptera at Água Boa and Perobão Streams, Iguatemi River basin, Brazil. Both are first order streams with similar length that are impacted by riparian forest removal and silting. Quarterly samplings were conducted from March to December 2008 in the upper, intermediate and lower stretch of each stream. The Mantel test was used to check the influence of spatial autocorrelation on the Odonata composition. Spatial variations in the composition were summarized by the Principal Coordinates Analysis (PCoA) using Mantel test residuals. The effects of spatial correlation on richness and abundance were investigated by the spatial correlogram of Moranʼs I coefficients. The most representative genera in each stream were identified by the Indicator Value Method. The spatial variations in the attributes of the assemblages were assessed using analysis of variance of null models. We collected 500 immature individuals of 23 genera and three families. Among the attributes analyzed only the composition and abundance showed significant spatial differences, with the highest mean abundance found in the Perobão Stream. Miathyria and Zenithoptera were the indicator genera of the Água Boa Stream and Erythrodiplax, Libellula, Macrothemis, Progomphus and Tramea were the indicator genera of the Perobão Stream.

Relative abundance and reproductive tactics of a Loricariidae species at Saraiva Lagoon, Ilha Grande National Park, MS-PR, Brazil

This study aimed to evaluate population abundance patterns and the main events in the reproductive cycle of Loricariichthys platymetopon at Saraiva Lagoon, Ilha Grande National Park, MS-PR, Brazil. Monthly samplings were conducted from October 2004 to September 2005 in three sections of the lagoon: entrance, middle and end, which resulted in the capture of 175 individuals. Spatial and temporal variation in abundance was obtained through CPUE (number of captured individuals/1000 m² of gillnets in 12 hours). The reproductive tactics considered were: duration, time and location of spawning, oocyte diameter and fecundity. The highest relative abundance was recorded in February, in the middle section of the lagoon, and the reproductive period lasted from September to February. The prevalence of females with spent ovaries and at rest in the following months indicated that reproductive activity ceased during autumn and winter. We observed that reproduction was high at the end section of the lagoon. The recorded mean oocyte diameter was 1.67 (SD ± 0.76) mm, mean absolute fecundity was 962.1 (SD ± 382.48) oocytes, and relative fecundity was 7.60 (SD ± 2.25) oocytes/g and 5.13 (SD ± 0.75) oocytes/cm. These tactics, probably are related to the settlement of L. platymetopom in Saraiva Lagoon, as well as in the different biotopes of the Upper Paraná River floodplain.

[Issues related to consent to healthcare decisions in children and adolescents]

The process of consent to healthcare decisions in children and adolescents often set physicians difficult problems. From what age is a child able to understand the information given to him or her about illness and treatment? Is an ill child indeed in the capacity to give his or her voluntary consent to treatment? How to define and to assess the capacity of an ill child to take part in treatment decisions? More than the age of the child, it is his or her level of cognitive, emotional and social development and its interactions with illness that will determine his or her degree of involvement in the decision-making process. There is a moral and ethical need to respect the rights and autonomy of every individual, regardless of age. This does not mean viewing children and adolescents as rational and autonomous decision-makers. This implies that we must promote their developmentally appropriate participation in shared decision-making with parents and physicians. Therefore, instead of asking, "should children and adolescents be granted absolute autonomy in decision making?" we ought to ask, "should we treat children and adolescents like people?"

[Antidepressant use in children and adolescents]

Relative to placebo, selective serotonin reuptake inhibitors (SSRI) are efficacious for paediatric affective disorders, although their clinical effects appear relatively modest in major depressive disorder, intermediate in obsessive-compulsive disorder, and stronger in anxiety disorders. If SSRIs modestly increase the risk of occurrence of suicidal ideation and behavior, several studies show that their use is associated with a significant decrease in the suicide rates in children and adolescents, probably because of their efficacy, compliance, and low toxicity in overdose.

Inter-annual variations in the abundance of young-of-the-year of migratory fishes in the Upper Paraná River floodplain: relations with hydrographic attributes

In this study, we identified and characterized the hydrographic attributes related to the success of recruitment of migratory fishes in the Upper Paraná River floodplain. To achieve our objectives, we analyzed inter-annual variations in the abundance of young-of-the-year (YOY; index of recruitment) of six migratory species and their relations with hydrographic attributes. Recruitment was related to the intensity, duration (in different fluviometrical levels), elasticity, number of pulses, greater uninterrupted overflow and delay of the floods (all obtained using the PULSO software). Collections of fish were conducted in the period between January 1987 and November 2007 in distinct environments (river channels, secondary channels and connected and disconnected floodplain lakes) distributed along three subsystems (Paraná, Baía and Ivinheima). Relations between recruitment and the attributes of interest were determined through analysis of covariance. In the studied period, the highest abundances of YOY were registered in 2007, followed by 1992, 1993, 2005 and 1988. The abundance of YOY was positively correlated with an intensity of high water levels (potamophase) and the duration of potamophase 1 and negatively with the duration of low water levels (limnophase) and a delay of flood. Higher hydrometric levels (540 and 610 cm for Paraná and 325 and 450 cm for Ivinheima) and greatest uninterrupted overflow presented different relations (significant interactions) among subsystems, but all with positive effects on recruitment. Results evidenced that recruitment responded better when floods started in January with potamophase intensities above 610 cm and water levels above 450 cm over a period of 50 days and repeated every two years (or > 610 cm for 38 days and repeated every two or three years). Therefore, artificial control of the floods at intervals of two or three years by manipulating the discharge of dams located upstream from the floodplain in a way that promotes potamophases with the potential to ensure recruitment of migratory species may become an important tool for conservation of migratory fish species in the floodplain.

Improved laboratory values of the H2 Lyman and Werner lines for constraining time variation of the proton-to-electron mass ratio

Two distinct high-accuracy laboratory spectroscopic investigations of the H2 molecule are reported. Anchor lines in the EF1Sigmag+-X1Sigmag+ system are calibrated by two-photon deep-UV Doppler-free spectroscopy, while independent Fourier-transform spectroscopic measurements are performed that yield accurate spacings in the B1Sigmau+-EF1Sigmag+ and I1Pig-C1Piu systems. From combination differences accurate transition wavelengths for the B-X Lyman and the C-X Werner lines can be determined with accuracies better than approximately 5 x 10(-9), representing a major improvement over existing values. This metrology provides a practically exact database to extract a possible variation of the proton-to-electron mass ratio based on H2 lines in high-redshift objects. Moreover, it forms a rationale for equipping a future class of telescopes, carrying 30-40 m dishes, with novel spectrometers of higher resolving powers.

Blockage of migration routes by dam construction: can migratory fish find alternative routes?

The present study explored the interaction between the upriver migration of fish and the blockage of their migration routes by dam construction. Specifically, we studied (i) the capacity of migratory fish to locate alternative routes in the presence of an obstacle, and (ii) the behavior of the fish after they were artificially transferred to the reservoir. With the use of the mark-recapture technique (tagging), the study was carried out near Porto Primavera Dam (UHE Engenheiro Sérgio Motta) between 1994 and 1999, a period prior to the closure of the floodgates and the installation and operation of the fish pass facilities. The fish were caught in the dam forebay downstream, marked with LEA type tags, and released upstream (5113 individuals; 14 species) and downstream (1491; 12) from the dam. The recaptures were carried out by local professional and amateur fishermen. A total of 188 individuals (2.8%) were recaptured, mostly the curimba Prochilodus lineatus. Nearly half of the recaptures downstream occurred in tributaries, especially in the Paranapanema River, indicating that in the presence of an obstacle the fish are able to locate alternative migration routes. The remainder stayed in the main channel of the Paraná River, at a mean distance of less than 50 km from the release point. Of the fish released upriver from the dam, approximately half were recaptured downriver. Although the river was only partly dammed, the movement of the fish downriver suggests that they became disoriented after being transferred. Those that remained upriver avoided the reservoir and moved, rather rapidly, toward the lotic stretches farther upstream. From these results it is clear that, in the course of the decision process in installing fish passes, it is necessary to take into account the existence of spawning and nursery areas downriver and upriver from the reservoir.

[Sleep in adolescents and its disorders. A survey in schools]

OBJECTIVES

Numerous studies emphasized the high prevalence of sleep problems in adolescents. However, it remains to be seen whether these problems are developmental or if they are related to pathological conditions. In order to try to answer this question, we conducted an epidemiological study investigating the prevalence and correlates of sleep disorders in a population of high school adolescents.

METHOD

The sample for this investigation consisted of 652 high school students (344 males and 308 females), aged 13 to 19 years (mean age: 15.1 1.2 years), attending colleges in the North of France. Data for the study were obtained by means of revised versions of the INSERM self-report questionnaires for adolescents. One questionnaire included 113 response choice items investigating the sleep parameters and the sociodemographic, behavioural, health, and environmental condition of the subject. This questionnaire was completed by a self-portrait questionnaire including 27 response choice items about mood, anxiety, instability and the quality of relations with others. In addition, a clinical examination was performed by the clinicians of the school health department in order to investigate the medical history of the subject and his (her) pubertal development.

RESULTS

In a first step, statistical analysis showed some significant differences in sleep rates and troubles between males and females. If the total sleep time was found similar in males and females, females were found exhibiting significantly earlier bedtime (p<0.01) and waking time (p<0.005) than males. In addition, trouble falling asleep (p<0.0001), nightmares (p<0.001), need for daytime sleep (p<0.05), and stimulant pill intake (p<0.05) were found significantly more frequent in females. Then, the adolescents were classified into two subgroups. "Insomnia group" included the students who answered "often" or "always" to one of the five questions about: having trouble falling asleep, the occurrence of early awakenings, their need for daytime sleep, sleeping pill intake, and bad sleep quality. "Non insomnia group" included those who answered "never" or "sometimes" in response to the five questions. Results showed that 233 adolescents (35.7%) exhibited persistent sleep disorders, insomnia type. 40.2% of females and 31.6% of males were included in the "insomnia group" (p<0.05). Pubertal development was found significantly more advanced in the "insomnia group" adolescents, more particularly in females. In the same way, concerns about body weight (46.7% vs 38.8%; p<0.005), size and shape (15% vs 8%; p<0.01) were found significantly more frequent in the "insomnia group"; 32.3% of the "insomnia group" adolescents vs 17.9% in the "non insomnia group" reported health problems (p<0.0001). School difficulties were found significantly more frequent in the "insomnia group" compared to the "non insomnia group". The proportion of subjects who have previously repeated at least one school year (p<0.01), who reported bad school performances (p<0.01), and who reported to be "sometimes" or "often" away from school (p<0.01) was significantly higher in the "insomnia group" than in the "non insomnia group". In the same way, data showed that school investing was also significantly weaker in the "insomnia group" adolescents (p<0.01). The proportion of subjects who believed that their relations with parents (12.4% vs 6%; p<0.05), teachers (21.4% vs 10.5%; p<0.0001), or peers (10.2% vs 4.1%; p<0.002) was found significantly higher in the "insomnia group". Risk behaviours were also significantly more frequent in the "insomnia group" adolescents: suicidal ideation (25.1% vs 11.7%; p<0.001), suicide attempt (7.3% vs 3.6%; p<0.05), psychotropic drug use (11% vs 4.9%; p<0.02), regular stimulant drug use (10% vs 5.1%; p<0.005), regular tobacco use (7.8% vs 2.2%; p<0.001), regular alcohol use (13.3% vs 8.3%; p<0.05), and illicit drug use (5.2% vs 1%; p<0.001). Lastly, all the dimensions of the self-portrait were found significantly more affected or negative in the "insomnia group" than in the "non insomnia group". For example, the proportion of subjects who described themself usually sad (10.2% vs 3.4%; p<0.001), anxious (54.9% vs 40.5%; p<0.0001), downcast (41.1% vs 32.6%; p<0.05), or instable (56.9% vs 41.7%; p<0.0001) was significantly higher in the "insomnia group".

CONCLUSION

In this descriptive study, if some data suggest that pubertal development may be involved in the sleep rates or troubles observed in adolescents, the results also show that persistent sleep disorders are significantly associated with physical, psychological or social difficulties. In summary, this study shows that it is essential to take an interest in the quality of sleep in adolescents, which may be a way to approach their psychosocial difficulties.

[Role of the implicit theories of intelligence in learning situations]

Most studies have tried to explain the school difficulties by analysing the intellectual factors that lead to school failure. However in addition to the instrumental capacities, authors also recognize the role played by other factors such as motivation. More specifically, the theory of achievement motivation aims to determine motivational factors involved in achievement situations when the students have to demonstrate their competencies. This paradigm attributes a central place to beliefs in order to explain children's behavior in academic situations. According to Dweck, it seems that beliefs about the nature of intelligence have a very powerful impact on behavior. These implicit theories of intelligence create a meaning system or conceptual framework that influences the individual interpretation of school situations. Thus, an entity theory of intelligence is the belief that intelligence is a fixed trait, a personal quality that cannot be changed. Students who subscribe to this theory believe that although people can learn new things, their underlying intelligence remains the same. In contrast, an incremental theory of intelligence is the belief that intelligence is a malleable quality that can increase through efforts. The identification of these two theories allows us to understand the cognition and behavior of individuals in achievement situations. Many studies carried out in the academic area show that students who hold an entity theory of intelligence (ie they consider intelligence like a stable quality) have a strong tendency to attribute their failures to a fixed trait. They are more likely to blame their intelligence for ne-gative outcomes and to attribute failures to their bad intellectual ability. In contrast, students who hold an incremental theory of intelligence (ie they consider intelligence as a malleable quality) are more likely to understand the same ne-gative outcomes in terms of specific factors: they attribute them to a lack of effort. This differential emphasis on traits versus specific mediators in turn fosters different reactions to negative events. Several studies have shown that entity theorists of intelligence are more likely than incremental theorists to react helplessly in the face of failure. They are not only more likely to make negative judgments about their intelligence from the failures, but also more likely to show negative affect and behaviors. This helpless response pattern is cha-racterized by a lack of persistence, and performance decrements. In contrast, incremental theorists, who focus more on behavioral factors (eg effort, problem-solving strategies) as causes of negative achievement outcomes, tend to act on these mediators. They try harder and develop better strategies and continue to work. Some authors have tendency to consider implicit theories of intelligence as a disposition or a stable dimension. But in the last few years, several studies showed that people's theories are not fixed traits; they are beliefs that may be influenced. These studies also suggested that students use the two types of beliefs and that the context determines the choice between the two types of theories. According to these authors, the psychological state of the student depends on dispositional factors but also on situational factors. Thus, several studies have tried to demonstrate that it is possible to modify experimentally implicit theories of intelligence and subsequent cognitions and behaviors by modifying situational factors. Several studies have demonstrated that it was possible to induce students to adopt one of the two theories of intelligence by presenting them a scientific article that compelling argued for either an entity or an incremental view of intelligence. The results showed that participants who had received the entity theory induction exhibited more evidence of a helpless reaction to failure. These studies show that some of the judgments and reactions associated with implicit theories can be experimentally induced by manipulating participant theories. However in the context of school difficulties, only few works have been conducted. We think that the model of the motivation of achievement would allow us to better understand maladjusted behaviors that engender failure and scholastic exclusion. In one study, reseachers have demonstrated that children with mental disorders are less likely than other children to hold an incremental theory of their intellectual abilities. Other studies have demonstrated that entity theorists interpret their bad results according to their global intelligence level by negatively judging their global abilities ("I think I am stupid"). It is interesting to note that these students make the same attributions as depressive students. These results reveal the need to determine systems of beliefs within populations with anxiety or depressive symptoms in order to characterise their motivational profiles. Indeed, we think that these symptoms contribute to modify implicit theories of intelligence and the nature of the subsequent scholastic achievement. Finally, we think that it is inte-resting to demonstrate the positive motivational effects of the experimental induction of the incremental theory. A series of studies showed that children's theories of intelligence expe-rimentally induced will influence their tendency to persevere in the face of failure. Like normally developing children, children with mental disorders were more likely to prefer challenging activities and report high levels of interest-enjoyment when the task was presented as one which is improvable. It suggests that although children with difficulties are pessimistic about improving their intellectual capacities, if a new task is introduced in a way that highlights the possibility of self-improvement (incremental theory), then they will pursue the challenge in an adaptive manner (strong perseverance, enjoy, and important interest). These results are very inte-resting. Indeed, highlighting an incremental theory had a po-sitive motivational effect on behavior in achievement situations. In addition, all these results also may open up several interesting perspectives for the treatment of learning disabi-lities. The results should lead to plan programmes of cognitive therapy in order to modify beliefs that underlie maladjusted achievement behaviors of children and adolescents in scholastic failure.

[An assessment of stress in adolescent inpatients]

Hospitalisation often remains stressful for adolescents. Therefore the improvement of life conditions and management of poorly adolescents during their hospital stay grows into an important concern in the medical staff. However, there is a lack of standardized instruments for an objective and reproducible assessment of problems related to this subject. The Hospital Stress Rating Scale (HSRS), validated in hospitalized adult patients, seems to be an interesting tool allowing an assessment of the level of stress and to specify the stressful factors.

SUBJECTS AND METHODS

During ten months, 107 adolescent inpatients, 39 males and 68 females, aged on average 13.5 +/-1.5 years, were included in the study. In addition to the HSRS, in a version adapted for adolescents, two other self-report questionnaires were used: the Toulouse Stress Rating Scale (TSRS), which is a rating scale validated to assess the level of stress and to identify the clinical manifestations of stress in adolescents, and the Toulouse Coping Rating Scale (TCRS), which is a rating scale validated to assess the coping style of adolescents in stressful situations. The sociodemographic and clinical characteristics of the studied subjects were collected by a standardized questionnaire.

RESULTS

A significant correlation was found between the HSRS mean total score and the TSRS mean total score. The HSRS item by item analysis showed that the nature of the stressors varied according to the clinical characteristics of the subjects. Lastly, the coping style was found having a significant influence on the level of stress reported by the subjects.

CONCLUSION

Even if they were obtained in a relatively small sample, these results show that the HSRS is a useful tool to assess the stress reported by the hospitalized adolescents. Such an instrument may be useful to plan aid and preventive strategies and to assess their impact in hospitalized adolescents.

Un trouble rare et peu étudié : la schizophrénie chez l’enfant. À propos d’une observation

Childhood-onset schizophrenia is rare: its prevalence is about 50 times lower than the one observed in adulthood. It is also frequently unrecognized, notably because its clinical aspect varies with age. The authors report the case of a prepubertal girl who developed a typical clinical picture of schizophrenia (paranoid subtype) by age 9.

CASE REPORT

The patient was 10 years old when she was hospitalized for a relapse of a suspected childhood-onset schizophrenia. Several significant mental disorders were found in her family history: her mother was treated for mood disorders (including dysthymia and major depression with postpartum onset), while her father and a aunt exhibited schizophrenic disorders. In addition, prenatal and perinatal events (including probable prenatal maternal infection and obstetric complications) were reported by her mother. Demonstrable impairments were already present in her premorbid development: from the age of 3.5, she showed significant manifestations of behavioural inhibition and separation anxiety, severe difficulties in social adaptation, and language abnormalities (qualified by her general practitioner as selective mutism). At the age of 9, when her mother was hospitalized for a diabetes mellitus, she suddenly showed auditory and visual hallucinations associated with delusions. Their content included filiation, somatic, and persecutory themes. Grossly disorganized behaviour (and more particularly catatonic motor behaviours including catatonic rigidity and negativism and bizarre postures) was also observed. Negative symptoms (eg anhedonia, affective flattening, and alogia) were noted. Her IQ scores were 74 in the verbal subtests and 53 in the performance subtests. Because the diagnostic of childhood-onset schizophrenia was suspected, a neuroleptic treatment, haloperidol 3 mg/day, was tried. After a partial remission during a few months period (characterized by a decrease in delusions, anxiety and sleep difficulties), she showed a relapse leading to her hospitalization. At the time of her admission, she showed severe manifestations of separation anxiety including agitation, anger, crying, and insomnia, for which she received a short-lived treatment by lorazepam. When sedation was obtained, the clinical picture proved similar to the one previously observed: hallucinations, delusions, grossly disorganized behaviour, and thought disorder were noted. As soon as the diagnostic of childhood-onset schizophrenia was confirmed, she was administered a new antipsychotic agent, amisulpride, at dose of 600 mg/day. This treatment was going on during several weeks with no significant clinical effect. Because the early onset of the disorder, the family history of schizophrenia, and the lack of effectiveness of the two previously administered antipsychotic agents, a treatment with clozapine was started at the dose of 12,5 mg/day. From the outset of this treatment, clinically significant reductions in hallucinations and disorganized behaviours were noted. Dose was then progressively increased until 200 mg/day, resulting in significant improvement in cognitive and motor functioning. The patient is now in an educational institute. Her adaptation is considered satisfactory, in spite of regular exacerbations of delusions in response to stressful life events. Treatment with clozapine is going on, without any significant undesirable clinical effects.

DISCUSSION

If an abrupt onset is rarely observed in prepubertal children, all the authors report that patients with very early onset schizophrenia show to have demonstrable impairments in their premorbid language as well as in their motor and social development. In addition, several studies suggest that more pronounced early developmental abnormalities are usually associated with a poor outcome in schizophrenia. The clinical picture also agrees with recent studies showing that in children paranoid subtype is as frequent as seen in adult disorders. If genetic factors play a significant role in the pathogenesis of schizophrenia, the notion that such factors may be more salient in very early onset and more severe cases is now usually accepted. However, a number of environmental factors, including prenatal maternal infections and perinatal complications, may also be implicated in the pathogenesis of schizophrenia, in addition to genetic factors. Because a significant relationship between stressful life events and exacerbations in positive symptoms was found in the case reported, the authors examine the role of such stress factors in the pathogenesis of schizophrenia and in the course of illness. A brief review of studies that have examined the effects of antipsychotic agents in children with schizophrenia underscores the paucity of data available to guide clinicians in this area. However, these data suggest that children who receive conventional neuroleptics experience significant adverse effects, primarily sedation and extrapyramidal symptoms. In addition, they suggest that new antipsychotic agents, such as clozapine, may be more effective than conventional neuroleptics, particularly in negative symptoms. Lastly, the authors emphasize the poor outcome usually reported in childhood-onset schizophrenia, highlighting the need of a long-term pharmacological and behavioural treatment.

CONCLUSION

This case report, such as others, supports the hypo-thesis that there is a clinical continuity between early and later onset schizophrenia. It also suggests that very early onset schizophrenia is a more severe form of the disorder and may be secondary to greater familial vulnerability. Consequently, systematic studies of these patients may be particularly informative and may provide important informations for understanding the etiologic processes involved in the pathogenesis of schizophrenia.

[Hearing impairment and psychopathological disorders in children and adolescents. Review of the recent literature]

OBJECTIVE

Hearing impairment is a multifaceted condition with medical and social aspects. If the neuropsychiatric impact of deafness on children has been investigated by researchers from a variety of fields and backgrounds, their conclusion is that children with hearing impairment follow many different developmental pathways. The aim of this paper is to examine the relationships between hearing impairment and mental health and the effect of impaired communication on family development.

METHOD

From a review of the literature, the authors examine the relationships between hearing impairment and mental disorders in children and adolescents in terms of prevalence, clinical features and etiological factors. The fami-ly dynamics and the parents-child interactions were also explored.

RESULTS

The assessment of psychiatric disorders in hearing-impaired children sets some methodological pro-blems. Accurate evaluation is hampered by the immature language exhi-bited by many hearing-impaired children and by the difficulties that may be encountered in establishing rapport if the child does not understand the examiner's verbal exchanges. Several authors point out the lack of communication skills and experiences with hearing-impaired children on the part of many examiners. In addition, delays have been observed for the development of social maturity in hearing-impaired children and the parents' descriptions may reflect their own worries, rather than the emotional-behavioral functioning of the child. The measurement of psychiatric symptoms is then compromised insofar as many of the assessment procedures are highly verbal and were standardized for normal-hearing children. These difficulties may explain that the pre-valence rates of mental disorders in hearing-impaired children and adolescents found in the literature vary from 15% to 60%. If autism and deafness may both confound each others' dia-gnosis, several studies also point out the high comorbidity observed between these 2 conditions. The significance of this association remains unclear. Many of the authors conclude that hearing impairment is unlikely to be an etiological factor in autism. However, auditory impairment may be a marker for brain damage in autism. Although some studies showed high rates of depression and anxiety disorders, particularly social phobias, in deaf and hard-of-hearing children and adolescents, most of the studies conclude that the prevalence of affective disorders in hearing-impaired children and adolescents is comparable with estimates of prevalence for hearing young people. A number of studies have suggested that deaf children show greater degrees of impulsivity than hearing children. However, it seems that this background of greater impulsivity does not lead to higher rates of attention-deficit/hyperactivity disorder (ADHD) among deaf children. Using standardized instruments to estimate the prevalence of ADHD in this population, recent studies conclude that deaf children with hereditary deafness are not at greater risk of developing ADHD but that children with acquired deafness are, and that this difference is probably related to the medical conditions and family climates distinguishing these two groups. Psychotic disorders are no more common among hearing-impaired young people than among young people with normal hearing. However, some recent studies showed that the presentation of schizophrenia can differ in deaf people because of the high frequency of visual hallucinations observed in them. Lastly, if primitive personality has been described as being more prevalent among hearing-impaired children and adolescents, most of the studies found a normal range of emotional-behavioral functioning in them. In summary, if varying incidences of emotional disturbances and behavioral problems have been reported for hearing-impaired children and adolescents, except autism, it seems that children with hearing impairment experience the same range of mental health problems as hearing children. A variety of demographic, medical and educational factors were investigated as possible etiological factors for the psychiatric disorders observed in hearing-impaired children. Factors such as medical conditions, degree of deafness, communication ability and social deprivation may play a role. However, many studies also emphasize that a number of other variables, including educational methods, parental adaptation and parental support, may have an impact, positive or negative, on the development of the hearing-impaired child. By this way, numerous investigations have shown that deaf children of deaf parents attain better emotional and cognitive development than do deaf children of hearing parents.

CONCLUSION

A number of questions remain about the neuropsychiatric and psychosocial aspects of hearing-impairment in children. For instance, few studies have been conducted to examine the impact of the different methods of communication and education on the psychosocial adjustment of deaf children. However, this review clearly show that appropriate and effective management can occur only when the mental health professionals are know-ledgeable and sensitive to the unique characteristics and experiences of hearing-impaired children and adolescents.

[Hearing impairment and cognitive development]

The study of the cognitive abilities of hearing-impaired children is important for both practical (e.g. to determine appropriate teaching strategies) and theoretical reasons (e.g. to examine the role of language in thought processes). The aim of this paper is to examine the cognitive function of hearing-impaired children from a review of the literature. If most studies show that deaf children are similar to normal children in virtually all aspects of cognitive function, many studies also emphasize pronounced differences in their academic achievement. Besides the degree of hearing loss and the age at onset of deafness, environmental factors (such as parental support and educational methods) seem to play an important role in the cognitive development and academic success of these children. This underlines the importance of the measures adopted for the deaf children as they may have a positive or negative impact on their development.

[Obsessive-compulsive disorder in children induced by streptococcal infection]

FROM OBSESSIVE-COMPULSIVE DISORDER TO PANDAS: Obsessive-compulsive disorder (OCD) represents a potentially severe and handicapping disorder that affects several hundreds of thousands of children in France. OCD has, for many years, been considered as a neurosis resulting from mental conflicts. It is currently seen as a neurobiological disorder, the etiological substratum of which is more organic than mental. Recently a sub-type of OCD was isolated in children following infection by Group A b-hemolytic streptococci. This sub-type has been described as Paediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infections (PANDAS). A NEW PHYSIOPATHOLOGICAL APPROACH: The putative dysimmune relationship between bacterial infection and neurotic disorder has led to the development of an original etiopathogenic model that may lead to new therapeutic strategies. The clinical case report of an adolescent presenting with trichotillomania associated with recurrent pharyngitis is a good illustration of this. PUBLISHED DATA: Data published in medical literature over the last 10 years indicates a 10% prevalence in the young suffering from OCD, i.e. 0.1 to 0.3% of the young population.

[Alpha-interferon and mental disorders]

The interferon alpha stands as a reference both in oncology and virology. But its efficiency is limited by frequent somatic as well as neuropsychic side effects. As a matter of fact, the reduction or the ending of a chemotherapy treatment come chiefly from the psychiatric complications caused by the use of interferon. For about 30% of patients, various psychic disorders are noticed: personality disorders, mood disorders, anxiety states, suicidal tendencies, manic and psychotic symptoms. We thus propose a review which shall be completed by a discussion on wether the interferon is responsible or not of the appearance of the described mental disorders. We shall conclude with a synthesis of the proposed practical management when confronted with such disorders. Psychiatric complications under interferon-Alpha. The appearance of psychiatric complications caused by interferon has been the subject of many publications. They have also raised the question of the toxicity mechanism which is still misunderstood today. This toxicity appears to be dose-dependent with variations depending on the daily dose given, the mode of administration, the combination with other chemotherapy treatments, the concomitance with a cerebral radiotherapy or a medical history of psychiatric disorders. Most of these effects occur after three weeks of treatment but non specific neuropsychic symptoms can be observed earlier. Non specific symptoms. They appear early but are difficult to detect, though they bring together a whole lot of clinical signs: asthenia, irritability, psychomotor slowdown, depressive mood or even a real "subsyndromic" depressive syndrome, anorexia, decline of the libido, concentration and attention problems, dizzy spells and headaches. Some authors have described intense and fluctuating of personality, mixing anxiety, irritability and disorder of drive control. Depression. Depression is the most frequently found psychiatric pathology in studies but the real frequency of clear cases of depressive problems is difficult to determine through lack of serious studies. So the incidence of depressive disorders usually varies from 5 to 15%. The depressive syndrome can settle as soon as the first week treatment, with a peak in the frequency during the first and third months. The seriousness and the incidence of this syndrome seem to be dose-dependent. The gravity of this complication lies in the suicidal risk, a risk all the more dreadful since there is not any identified risk factor. Suicides and suicidal behaviours. Serious complications, because they act directly on the vital prognosis. However fortunately, suicidal behaviours only represent a minority within all the side effects attributed to the interferon-alpha. These actions fit into three main clinical dimensions: complication of a severe depressive syndrome, confusional context and disorder of the impulses control. In practical terms, prevention proves to be difficult without identified predictive factors. Nevertheless, some authors point out the importance of aggravating comorbid disorders like alcoholism or the coinfection by the HIV. Manic syndrome. The appearance of a manic state under a chemotherapy treatment seems to be rare, given that there have been only a dozen cases published around the world. But these observations are interesting as far as both the study of imputability and the understanding of the toxicity mechanisms are concerned. Most of the cases deal with patients without a family or personal history of psychiatric disorders, and whose symptomatology disappears with the end of the treatment, which is an argument in favour of the imputation of the interferon in the appearance of manic disorders. In addition, some authors introduce the notion of tertiary mania: the appearance of an autoimmune hypothyroidism in relation with interferon and leading to athymic elation. Eventually, the appearance of manic problems at the end of the treatment makes it possible to speculate about the physiopathological mechanisms that are at issue. Anxiety disorders. These disorders are not much described: they generally are already existing disorders (like phobic or obsessive compulsive disorders), reactivated or aggravated by the interferon-alpha molecule. Adaptation disorders. It deals with adaptation disorders along with anxious temper coming at the beginning of the treatment. These problems are more concerned with the announcement of the diagnosis and its seriousness than with the toxicity of the interferon-alpha molecule. Psychotic states. There are less papers on the prevalence of psychotic disorders during the treatment, or at the end of it. But they can be found in both viral and malignant pathologies. A large retrospective study has shown ten cases of psychotic disorders and that in the absence of history of psychiatry or of a HIV co-infection. In every case the psychiatric aspect is stopped by the ending of the treatment or by an appropriated treatment. Usually, the few cases of paranoïd delusion described in papers seem to appear between one and three months of treatment, with patients having a history of psychiatric disorders. Aggravation of pre-existing mental disorders. Numerous authors have reported the recurrence of addictive behaviours (alcohol or other psychoactive matter) by weaned patients. Imputability to interferon-alpha in psychiatric disorders. It is difficult to draw the relationship between the chemotherapy with the interferon-alpha treatment and neuropsychiatric complications because there is a lack in specific studies. Nevertheless, it seems to be causal relations between the prescription of interferon and the appearance of psychic disorders. As a matter of fact, even if there is neither predictive criterion nor diagnosis of clinical type (set apart a dose effect), it is clear that there are diagnostic criteria of chronological kind: delay of appearance and disappearance of side effects compatible with the kinetics of the molecule and test of positive reintroduction. The imputability is thus most likely towards, given the reported clinical observations and signs of direct cerebral toxicity described for interferon: induction of neurophysiological changes among healthy volunteers, reversible EEG impairments the second week of treatment, direct vascular and neurological toxicity. Eventually, authors have shown that the psychiatric morbidity could be more important among patients under treatment than in a control group. In conclusion, the imputability of interferon appears to be very likely, more particularly in the appearance of mood disorders, mainly depressive ones, of manic syndromes and of certain psychotic episodes.

MANAGEMENT

The most numerous therapeutic propositions naturally concern the depressive syndromes, because of their high frequency. In a recent article, the authors have detailed the pharmacological criteria of the ideal molecule: limited hepatic metabolism, low rate of proteinic fixation, long half-life and absence of active metabolite. So they advise not to prescribe imipraminic molecules and recommend the use of some SRI in first intention: citalopram and sertraline mainly, paroxetine to avoid given its pharmacological features that do not seem adapted. Only the minalcipram seems to show all the theoretical advantages described above. If there is an indication in the introduction of an anxiolytic medication, we shall prefer a benzodiazepine with short half-life like loxazepam and alprazolam. Besides, all the publications point out the importance of a specific clinical observation during the treatment as well as in the six months following its end. The agreement must bear full medical costs, above all including psychotherapic and social aspects. The proposed treatments for the other disorders are conventional: haloperidol and lithium for bipolar disorders, fluvoxamine for obsessive compulsive disorders and neuroleptics for psychotic disorders.

CONCLUSION

The appearance of neuropsychiatric side effects during a chemotherapy using the interferon-alpha molecule is a frequent complication, the consequences of which can prove tragic: involvement of the vital prognosis, family and professional relation disturbances, compliance problems, risks of psychiatric morbidity at short and middle terms.... In spite of the absence of rigorous controlled studies, the imputability to the interferon of the appearance of psychological disorders appears very likely. So the role of the psychiatrist seems to be determining in the follow-up care of these patients who must be considered at high risk to develop a psychiatric pathology. The agreement to bear medical costs has to be made in narrow collaboration with clinical practitioners and must be part of a clinical continuity, from the pre-therapeutical evaluation to the remote follow-up care. Finally, it seems important to implement controlled studies, resting on a great diagnostic and methodological rigour, in order to clarify the toxicity mechanisms of interferon and to optimise the agreement to bear medical cost for the patients.

[Obesity, alexithymia, psychopathology and binge eating: a comparative study of 40 obese patients and 32 controls]

Alexithymia may be considered as a personality feature characterized by poorness of imaginary life, speech focused on actual facts and physical sensations, general inaccuracy in or paucity of the words used to express emotions, and recourse to acting out to avoid intrapsychic conflicts. The possible link between alexithymia and psychosomatic or psychopathological disorders is now well documented. In particular, studies suggested that alexithymia may be frequently observed in obese or bulimic patients. This study was designed to investigate the link between obesity and alexithymia according to the presence or not of binge eating problems; 40 obese female patients (BMI > or = 27.3) seeking obesity treatment and 32 normal weight women used as controls were included in the study. In the obese group, 11 patients (27.5%) exhibited binge-eating disorder according to the DSM IV criteria. Alexithymia was assessed using the Toronto Alexithymia Scale (TAS), and past and current mental disorders were assessed by means of the Structured Clinical Interview for DSM III-R (SCID). In addition, current depression was assessed using the Beck Depression Inventory (BDI). The mean TAS score was found significantly higher in obese patients than in controls (72.6 +/- 11.8 vs 65.2 +/- 9.3, respectively; p < 0.005). In the same way, alexithymia (defined by TAS score > or = 74) was found significantly more frequent in obese patients than in controls (52.5% vs 21.8%, respectively; p < 0.03). However, among obese patients no significant difference was found between patients with and without binge-eating disorder. Current major depression was also found significantly more frequent in obese patients than in controls (15% vs 0%, respectively; p < 0.03), and the mean BDI score was very significantly higher in obese patients (12.2 +/- 8.7 vs 4.6 +/- 4.6, respectively; p < 0.0001). Comparisons between obese patients with and without binge-eating disorder showed that only past major depression was found significantly more frequent in those with binge-eating disorder (81.8% vs 10.3%, respectively; p < 0.0001), although the mean BDI score was significantly higher in patients with binge-eating disorder (18.5 +/- 11.7 vs 9.8 +/- 5.9, respectively; p < 0.02). Group by group comparisons suggested that two factors may play a role in the correlation found between obesity and alexithymia. First, the mean TAS score was found significantly higher in subjects with low educational level (p < 0.05), obese patients exhibiting significantly lower educational level when compared to controls (p < 0.002). Then, a significant positive correlation was found between TAS scores and BDI scores (Spearman's test: p < 0.01), obese patients showing significantly higher BDI scores than controls (p < 0.0001). In order to confirm these results, a logistic regression procedure was performed in the total sample (obese patients + controls). Three factors were found significantly increasing the risk to get a TAS score > or = 74: low educational level (odds ratio: 3.56), past and/or current major depression (odds ratio: 2.77), and BDI score > or = 8 (odds ratio: 2.18). Obesity in itself had no significant effect on TAS scores. Our results confirm that alexithymia is a psychological feature frequently observed in obese patients. In our study, the correlation found between obesity and alexithymia appears to be irrespective of binge-eating disorder, and seems to be mediated by the educational level and the frequency of associated depression. However, further investigations need to be done in order to specify the relationships between obesity, alexithymia, low educational level, and depression.

[A case of acute psychotic episode after a single dose of ecstasy]

Over the last 10 years or so in Europe, there has been a development of the "ecstasy" phenomenon, which is the symbol of "recreational" drugs in general. Users, either alone or in private parties, are on the increase. The phenomenon is most frequent in England and in the Netherlands, with an estimated incidence of 13-18% amongst the 18-25 years old, which may reach 52% in "exposed populations", such as individuals who go to "techno" night clubs. In France, the prevalence is uncertain, but estimated at least 5% of males between 18 and 23 years old. Several substance, with more or less the same effects, are grouped together by the term "ecstasy", the best-known one being 3,4-methylenedioxymethamphetamine (MDMA), but there are also an N-demethylated derivative (MDA), methylenedioxyethylamphetamine (MDEA), N-methyl-benzodioxazolylbutanamine (MBDB) and 4-bromo-2,5-dimethoxyphenylethylamine (2-CB or Nexus). The psychopathological consequences of MDMA in man are relatively poorly understood. On the basis of series of cases reported in the literature, acute psychosis, chronic psychosis similar to paranoid delusions, flash-back phenomena similar to with LSD, anxiety/panic states and depressive mood disorders may occur. The case which we report is therefore that of an acute psychotic episode, with residual symptomatology 6 months later, which occurred suddenly following absorption of toxic substances (alcohol and ecstasy), at least 12 hours after taking the ecstasy tablet without his knowing it, in an individual without any previous psychopathology, other than moderate social phobia. Twelve cases of acute psychotic episodes after ecstasy have been reported in the literature. Two of them occurred after a single dose and one after 2 doses. No author was able to examined the previous history of the individuals accurately, nor any possible psychopathological history. Our patient did not have any previous history of psychosis, using a standardized validated interview, which his peers and family confirmed. He did however fulfil the criteria of "social phobia". Retrospectively, we noted the extent of his psychomotor disinhibition with ecstasy, which seemed to be proportional to the intensity of his previous social inhibition. This point does not explain the psychotic episode. From a neurobiologic point of view, acute psychotic disorders are often related to dysfunction of the mesolimbic dopaminergic system. During the first 3 hours, the effect of absorption of MDMA is a massive release of the serotonin, dopamine and noradrenaline stocks. Later, an acute hyposerotoninergic state is present. In our observation, the psychotic disorder appeared at least 12 hours after taking ecstasy, during the reduction phase of the intoxication. Toxicological analysis of the blood was negative (this detection is only positive for 24 hours). Like other authors, our hypothesis is that serotoninergic dysregulation affects the dopaminergic system. Sudden disappearance of serotoninergic feedback on the dopaminergic pathways, may contribute to an increase in the mesolimbic hyperdopaminergic state. In animals, it has been shown that serotonin depletion induced by MDMA, unmasks the effects of a hyperdopaminergic state. In addition, although it has not been mentioned much in the literature, MDMA disturbs dopaminergic function either directly, or through the peptidergic systems (neurotensin, substance P, dynorphines). A consistent series of arguments therefore suggest that there is a sudden central hyperdopaminergic state, which may be related to the appearance, sometimes de novo, of an acute psychotic disorder. From the published cases, psychotic disorders following absorption of ecstasy, appear to become chronic. Most of the cases occurred in individuals, who either abused multiple substances or were chronic ecstasy users. In a case like the one we report, in an individual with good general health, who is not a drug user and who has an acute episode following a single dose, the prognosis should be good. Similarly, a team from Milan has described the experience of 3 friends who had a brief psychotic episode, following ingestion of substances containing ecstasy. These episodes resolved completely, after rehydration and anxiolytic treatment. However, after 6 months' follow-up, our patient still has psychotic symptoms, albeit mild, but which were not present before the intoxication. The patient and his psychiatrist do not envisage changing or stopping his antipsychotic treatment. Other authors have described a lesion in the serotoninergic neurons, by making a parallel with toxic effects described in animals, in particular in primates, with MDMA. Degradation of the serotoninergic cell bodies and nerve endings has been suggested to occur with high doses and/or repeated doses of MDMA. Other authors show the large variations in MDMA and MDA metabolism. (ABSTRACT TRUNCATED)

[Post-traumatic stress, post-traumatic depression and major depressive episode: literature]

Although they are likely to add their effects, physical and psychic traumata (or traumas) can provoke in different ways the appearance of depressive symptoms sometimes common. Post-traumatic depression, reactional depression, major depressive disorder and post-traumatic stress disorder represent different clinical and nosographic disorders in despite of their occasionally common symptomatic core. Historically, it is interesting to note during the XXth century the true semantic change of the terms of trauma from the somatic field to the psychic sphere. Physical traumatism is often represented by a material shock for the subject and by its organic consequences. It is defined as an event that leaves its mark which itself inflicts and handicaps the vital trajectory of the subject. It primarily comprises brain and rachis injuries, whose evolution is frequently characterized by the occurrence/appearance of a depressive disorder, whose genesis rests on psychological but also neurobiologic and physical arguments. Thus major depressive disorders are often present in the course of various physical traumatisms mainly related to nervous system. In accordance with several studies, the prevalence of major depressive disorders ranges from 25% to 50%. These mood disorders occur in the year which follows the accidental event. Their average time of revelation is estimated at four months and their average duration lies between three and six months. Lastly, although these depressive illnesses present clinical symptoms comparable with those observed in other contexts, some nuances can be raised. Nonetheless, they confine sometimes with true clinical forms depending on the intensity, the form, the circumstances or the consequences of the trauma. Psychic traumatism doesn't have the same profile and rests for much dedicated with the reexperiencing. Thus for some authors, depression illness represents a disorder that occurs after a traumatic event whereas others see a differential diagnosis which exludes or which represents a comorbidity with post-traumatic stress disorder. The review of the literature allows us to emphasize the complexity of the links as well as the clinical and epidemiologic differences between stress disorder and major depressive disorder. From the clinical point of view, the major features of PTSD are articulated around a triad of symptoms. They include the reexperiencing symptoms of the traumatic event such as intrusive memories and recurrent nightmares, the protective reactions such as avoidance of the stimuli associated with the trauma and emotional numbing, and the arousal symptoms such as the startled response and hypervigilance. The complexity of this syndrom is due to the frequent combination of these symptoms with other nonspecific ones. As far as the mood is concerned (the mood symptoms are concerned), the regrouping of some of these symptoms allows the clinician to sometimes releave a depressive symptomatology without being able to assess the DSM diagnosis of major depressive disorder. Epidemiologic studies dealing with the risk of installation of a PTSD after a traumatic event reveal differences in the prevalence depending on the nature of the traumatic events: ranging from 1% in general population to 80% following some situations of extreme and durable psychic suffering. Between both poles, one finds a prevalence ranging between 20 and 50% following other events such as serious accidents, natural disasters or criminal assaults. The clinical features of depressive episodes comorbid or associated with PTSD have some characteristics making it possible to individualize various clinical forms as a function of traumatic event type: asthenic, characterial or with somatic symptoms. According to the majority of authors, the co-occurrence of post-traumatic stress disorder and major depressive disorder is high although differential diagnosis is sometimes difficult. However, conceptual differences remain and two conceptions are distinguished. For some authors, like Bleich and Shalev, there would not be true chronological evolution from PTSD to MDD. Moreover the presence of symptoms considered as pertaining to the mood register within the criteria of PTSD would be clearly predictive of the occurrence and the severity of the diagnosis but not of the chronicity. For others, there would be a continuity between post-traumatic stress disorder and major depressive disorder. It is the case in many studies of veterans but also for civilian traumatic events. It is also the case for the American national study of comorbidity in which Kessler concludes that for 78% of the subjects who present a comorbidity PTSD/MDD (comorbidity raised for 48% of the 5,877 subjects included), the mood disorder is secondary to PTSD. (ABSTRACT TRUNCATED)

An "accidental" acute psychosis with ecstasy use

Over the last 10 years, Europe has witnessed the development of the ecstasy phenomenon; this term is used to describe several products sharing more or less the same effects. The most widely used and hence the most well known is 3,4 MDMA, but MDA, MDEA, MBDB and even 2CB or nexus are available. The psychopathological consequences of MDMA use in man are relatively poorly understood. The case reported here involves an acute psychotic episode with residual symptoms after six months, with a sudden onset at least 12 hours after taking alcohol and ecstasy without realising it, in an individual with no previous psychopathology other than a moderate anxiety disorder. Twelve cases of acute psychotic episodes after taking ecstasy have been reported in the literature; two after taking the drug on two occasions and one after a single use. No authors have examined the previous mental state or possible previous psychopathology with any precision. The present subject had not displayed any previous psychotic behavior when tested with a proven standardized interview technique; this was confirmed by his peers and his family. He did, however, show signs of social phobia. Although the personality of an individual is a factor in taking a drug, and probably in the quality of the psychotropic effects experienced, a host of arguments favor the appearance of psychotic symptoms de novo, which were probably related to direct toxicity by MDMA and/or its metabolites on the serotoninergic neurons.

Hydrodynamic theory of density relaxation in near-critical fluids

This paper gives a complete hydrodynamic theory of density relaxation after a temperature step at the boundary of a cell filled with a nearly supercritical pure fluid in microgravity conditions. It uses the matched asymptotic expansion technique to solve the one-dimensional Navier-Stokes equations written for a viscous, low-heat-diffusing, near-critical van der Waals gas. The continuous description obtained for density relaxation in space and time confirms that it is governed by two fundamental mechanisms, the piston effect and heat diffusion. It gives a space-resolved description of density inside the cell during the divergently long heat diffusion time, which is shown to be the ultimate one to achieve complete thermodynamic equilibrium. On that very long time scale, the still measurable density inhomogeneities are shown to follow the diffusion of the vanishingly small temperature perturbations left by the piston effect. Temperature, which relaxes first to nonmeasurable values, and density, which relaxes on a much longer time scale, may thus appear to be uncoupled. The relaxation of density on the diffusion time scale is shown to be driven by a bulk expansion-compression process slowly moving at the heat diffusion speed, which is generated by heat diffusion coupled with the large compressibility of the near-critical fluid. The process is shown to be the signature of the thermoacoustic events that occur during the very short piston effect time period. The generalization of the theory to real critical behavior opens the present results to future experimental investigation.

13C(16)O(2): Global Treatment of Vibrational-Rotational Spectra and First Observation of the 2nu(1) + 5nu(3) and nu(1) + 2nu(2) + 5nu(3) Absorption Bands

The effective operator approach is applied to the calculation of both line positions and line intensities of the (13)C(16)O(2) molecule. About 11 000 observed line positions of (13)C(16)O(2) selected from the literature have been used to derive 84 parameters of a reduced effective Hamiltonian globally describing all known vibrational-rotational energy levels in the ground electronic state. The standard deviation of the fit is 0.0015 cm(-1). The eigenfunctions of this effective Hamiltonian have then been used in fittings of parameters of an effective dipole-moment operator to more than 600 observed line intensities of the cold and hot bands covering the nu(2) and 3nu(2) regions. The standard deviations of the fits are 3.2 and 12.0% for these regions, respectively. The quality of the fittings and the extrapolation properties of the fitted parameters are discussed. A comparison of calculated line parameters with those provided by the HITRAN database is given. Finally, the first observations of the 2nu(1) + 5nu(3) and nu(1) + 2nu(2) + 5nu(3) absorption bands by means of photoacoustic spectroscopy (PAS) is presented. The deviations of predicted line positions from observed ones is found to be less than 0.1 cm(-1), and most of them lie within the experimental accuracy (0.007 cm(-1)) once the observed line positions are included in the global fit. Copyright 2000 Academic Press.

[Neuropsychiatric disorders induced by MDMA ("Ecstasy")]

If neurotoxicity of MDMA (ecstasy) is now well documented in animals, it is not the same in humans. MDMA intoxication puts the problem of its possible link with the serotonin syndrome and the neuroleptic malignant syndrome. Neuropathological consequences following MDMA intake have been reported, including hemorrhaging and cerebral infarction, cerebral venous sinus thrombosis, and acute inflammatory CNS disease. However, the physiopathology of these complications remains unclear. In the same way, there have been various reports that have attributed MDMA to precipitating the onset of a wide range of psychiatric disorders including sleep disorders, cognitive disorders, panic attacks, depression, flashbacks, psychosis and severe paranoia. Findings suggest that these psychiatric manifestations might be consequences of MDMA induced brain serotonin neurotoxic lesions. All these data are examined from a critical review of the literature.