Biomedical subjects

Fernando Perez-Diaz

Publications and source records attributed to Fernando Perez-Diaz.

13 recordsLinked to original sources

PubMed2006

Spontaneous appetence for wheel-running: a model of dependency on physical activity in rat.

According to human observations of a syndrome of physical activity dependence and its consequences, we tried to examine if running activity in a free activity paradigm, where rats had a free access to activity wheel, may present a valuable animal model for physical activity dependence and most generally to behavioral dependence. The pertinence of reactivity to novelty, a well-known pharmacological dependence predictor was also tested. Given the close linkage observed in human between physical activity and drugs use and abuse, the influence of free activity in activity wheels on reactivity to amphetamine injection and reactivity to novelty were also assessed. It appeared that (1) free access to wheel may be used as a valuable model for physical activity addiction, (2) two populations differing in activity amount also differed in dependence to wheel-running. (3) Reactivity to novelty did not appeared as a predictive factor for physical activity dependence (4) activity modified novelty reactivity and (5) subjects who exhibited a high appetence to wheel-running, presented a strong reactivity to amphetamine. These results propose a model of dependency on physical activity without any pharmacological intervention, and demonstrate the existence of individual differences in the development of this addiction. In addition, these data highlight the development of a likely vulnerability to pharmacological addiction after intense and sustained physical activity, as also described in man. This model could therefore prove pertinent for studying behavioral dependencies and the underlying neurobiological mechanisms. These results may influence the way psychiatrists view behavioral dependencies and phenomena such as doping in sport or addiction to sport itself.

Amphetamine↗

PubMed2005

Dependency and suicidality in addictive disorders.

Excessive interpersonal dependency has been described in depression and addictive disorders. Moreover, excessive dependency and suicidality are linked in psychiatric subjects, but their relationships have not been studied in specific addictions. Separate samples of female anorectic patients (n=150), female bulimic patients (n=95), male (n=150) or female (n=68) alcoholics, male (n=94) or female (n=54) drug abusers and non-psychiatric control subjects (n=683) were included in the study. On the basis of a structured interview, suicidal ideations, number of previous suicide attempts and diagnoses of dependent personality disorder (DSM-IV) were collected, and the subjects completed the Interpersonal Dependency Inventory and the Beck Depression Inventory. Logistic regression analysis revealed that excessive dependency and notably dependent personality disorder increased the likelihood of suicidal ideation or suicide attempts with a range of 2.65 to 9.42 in bulimic patients, female alcoholics and male drug abusers. Excessive dependency in specific addictive disorders as well as in male non-psychiatric subjects could constitute a risk factor for suicide. This hypothesis must be confirmed using prospective studies.

Adolescent↗

PubMed2005

Individual cognitive training of reading disability improves word identification and sentence comprehension in adults with mild mental retardation.

Reading therapy has been shown to be effective in treating reading disabilities (RD) in dyslexic children, but little is known of its use in subjects with mild mental retardation (MR). Twenty adult volunteers, with both RD and mild MR, underwent 60 consecutive weeks in a cognitive remediation program, and were compared with 32 untreated control subjects. The experimental group showed a significant improvement in word identification, as measured by oral production (p=0.0004) or silent reading (p=0.023), and sentence comprehension (p=0.0002). Adults with MR appear to benefit from new approaches in the field of RD.

Adult↗

PubMed2005

Depressive personality dimensions and alexithymia in eating disorders.

An association has been reported between high levels of alexithymia and depression in patients with eating disorders. This study has examined alexithymic features and depressive experiences in patients with DSM-IV eating disorder (restricting anorexia, n=105; purging anorexia, n=49; bulimia, n=98) and matched controls (n=279). The subjects were assessed with the Toronto Alexithymia Scale (TAS-20); the Beck Depression Inventory; and the Depressive Experiences Questionnaire, which defines two types of depressive personality style (dependent and self-critical). The patients had high levels of alexithymic features and depressive symptoms. Comparisons of alexithymic features between patients and controls after adjustment for depression showed a significant difference between bulimic patients and controls for the TAS Difficulty Identifying Feelings factor, and between restricting anorexic patients and controls for the TAS Difficulty Describing Feelings factor. With regard to depressive personality styles, only scores on the self-critical dimension were significantly higher in bulimic patients than in restricting anorexic patients and controls. In the entire group of eating disorders, dependency was associated with the TAS Difficulty Identifying Feelings factor only in anorexic patients. Self-criticism, on the other hand, was associated with the TAS Difficulty Identifying Feelings factor in all subtypes of eating disorders, although the relationship was significantly stronger in restricting anorexic than in bulimic patients. The results of this study suggest that people with restricting anorexia and bulimia show specific clinical profiles associating alexithymic features and depressive dimensions.

Adolescent↗

PubMed2004

Executive dysfunctions as potential markers of familial vulnerability to bipolar disorder and schizophrenia.

Attentional and executive impairments have been found both in patients with schizophrenia and in their unaffected first-degree relatives, suggesting that they might be considered as familial vulnerability markers. Several studies have shown that the performance of bipolar patients does not significantly differ from that of schizophrenic patients, so that executive and attentional deficits might not be specific to schizophrenia. In the present study, we aimed to identify executive dysfunctions in schizophrenia and bipolar disorder that might be vulnerability trait markers specific to one or common to both of these diseases. We assessed cognitive performance of euthymic bipolar and schizophrenic patients, their unaffected first-degree relatives and a healthy control group, using neuropsychological tasks to test different components of executive function: the Verbal Fluency Test, the Stroop Word Colour Test, the Wisconsin Card Sorting Test and the Trail Making Test. The two groups of patients and their unaffected relatives demonstrated disproportionately increased slowness on the Stroop test in comparison to the normal healthy group. Patients with schizophrenia performed poorly on all the tests in comparison to the normal healthy subjects, while no other impairment was observed in the bipolar patients and in the relatives of schizophrenic and bipolar patients. Enhanced susceptibility to interference and reduced inhibition could be transnosographical markers for a shared familial vulnerability common to schizophrenia and bipolar disorders.

Adult↗

PubMed2003

Posture and balance responses to a sensory challenge are related to anxiety in mice.

Anxiety disorders and balance disorders share common clinical features related to perception such as spatial disorientation or dizziness. The search for the mechanism underlying this core of symptoms led us to investigate impairments in multisensory integration. In mice, the 'rotating beam test' allows analysis of changes in balance control and posture in response to a multisensory challenge. We used the BALB/c and C57BL/6 inbred strains of mice, known for their contrasted anxiety-related behavior. The level of anxiety was also manipulated using anxiolytic and anxiogenic pharmacological compounds. Despite equal sensori-motor abilities, anxious mice were more prone to fall off the rotating beam and showed more imbalance than non-anxious mice. Striking inter-strain differences in posture were also observed. Diazepam and beta-CCM reversed these strain-specific responses in opposite directions. We demonstrated that balance and postural strategies developed in response to a multisensory challenge vary as a function of the level of anxiety in mice.

Animals↗

PubMed2003

Depressive psychopathology and adverse childhood experiences in eating disorders.

PURPOSE: The aim of this paper was to investigate the diagnostic specificity of the self-critical and dependent depressive experiences in a clinical sample of eating disorder patients and to explore the impact of adverse childhood experiences on these dimensions of personality. METHOD: A sample of 94 anorexic and 61 bulimic patients meeting DSM-IV criteria and 236 matched controls were assessed with the Depressive Experience Questionnaire (DEQ), the abridged version of the Beck Depression Inventory (BDI) and the AMDP Life Events Inventory. Subjects presenting a major depression or a comorbid addictive disorder were excluded from the sample using the Mini International Neuropsychiatric Interview (MINI). RESULTS: Anorexic and bulimic patients showed higher scores than controls on both self-criticism and dependency sub-scales of the DEQ. Bulimic patients scored significantly higher than anorexic patients on self-criticism and reported more adverse childhood experiences. Finally, negative life events correlated only with self-criticism in the whole sample. DISCUSSION: Differences in the DEQ Self-Criticism between anorexics and bulimics could not be accounted for by depression since bulimic patients did not show higher BDI levels compared to anorexic patients and depressive symptoms measured with the BDI were not found to be significant predictors of diagnostic grouping in a logistic multiple regression. CONCLUSION: This study supports the diagnostic specificity of the dependent and self-critical depressive dimensions in eating disorders and strengthens previous research on the role of early experiences in the development of these disorders.

Adolescent↗

PubMed2003

Aggression and the three opioid families (endorphins, enkephalins, and dynorphins) in mice.

Previous studies suggest that brain opioid activity decreases aggression in animal models. The main objective of the current study was to examine the possible genetic relationship between intermale aggression and brain levels of enkephalins, endorphins, and dynorphins in 11 inbred strains of mice. Pursuit, rattling, and attack behaviors were observed in a dyadic encounter with a standard opponent. It appeared that, as expected, enkephalins and endorphins were always negatively correlated with aggression scores. The findings indicate that brain Met5-enkephalin levels were significantly and highly positively correlated with attack latency. Brain adrenocorticotrophic hormone (ACTH) and beta-endorphin levels were significantly and negatively correlated with the number of rattlings, which is consistent with the hypothesis that rattling is a stress-related behavior. In contrast with Met5-enkephalin, ACTH and beta-endorphin, the correlations between dynorphin A and aggression scores were nonsignificant and very low. These preliminary results suggest that common genetic sources of variation contribute to differences between the 11 inbred strains in both endogenous opioidergic systems and intermale aggression. Further studies are required to confirm the genetic relationship between offensive aggression and brain enkephalins and endorphins and to better understand the mechanisms underlying the role of endogenous opioids in offensive aggression with regard to opioid receptor activity.

Adrenocorticotropic Hormone↗

PubMed2003

[Relationships between alexithymia, depression and interpersonal dependency in addictive subjects].

In the scientific literature, the term of addiction is currently used to describe a whole range of phenomena characterized by an irresistible urge to engage in a series of behaviors carried out in a repetitive and persistent manner despite accruing adverse somatic, psychological and social consequences for the individual. It has been suggested that subjects presenting such behaviors would share specific features of personality which support the appearance or are associated with these addictive behaviors. Dimensions such as alexithymia and depression have been particularly well investigated. The aim of this study was to explore the hypothesis of a specific psychopathological model relating alexithymia and depression in different addictive disorders such as alcoholism, drug addiction or eating disorders. Alexithymic and depressive dimensions were explored and analyzed through the statistical tool of path analysis in a large clinical sample of addicted patients and controls. The results of this statistical method, which tests unidirectional causal relationships between a certain number of observed variables, showed a good adjustment between the observed data and the ideal model, and support the hypothesis that a depressive dimension can facilitate the development of dependence in vulnerable alexithymic subjects. These results can have clinical implications in the treatment of addictive disorders.

Adolescent↗

PubMed2002

Role of TNF-alpha receptors in mice intoxicated with the parkinsonian toxin MPTP.

The loss of dopaminergic neurons in Parkinson's disease is associated with a glial reaction and the overproduction of proinflammatory cytokines such as tumor necrosis factor alpha (TNF-alpha). TNF-alpha acts via two different receptors, TNFR1 and TNFR2, and is believed to have both a neuroprotective and a deleterious role for neurons. In order to analyze the putative role of TNF-alpha in parkinsonism, we compared the effect of the parkinsonian drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice lacking TNFR1, TNFR2, or both receptors and in wild-type littermates. We show that MPTP does not affect spontaneous activity or anxiety in any of the groups and that it reduces motor activity on a rotarod in double knock out mice but not in mice lacking only one receptor. Postmortem analysis revealed no differences in the number of nigral dopaminergic neurons whatever the group. In contrast, striatal dopamine level was slightly decreased in double knock-out mice and more reduced by MPTP in this group than in the other groups of mice. In addition, dopamine turnover was significantly more increased in double knock out mice after MPTP injection. These data suggest that TNF-alpha does not participate in the death of dopaminergic neurons in parkinsonism but that it slightly alters dopamine metabolism or the survival of dopaminergic terminals by a mechanism involving both receptors.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

PubMed2002

Criterion validity of the interpersonal dependency inventory: a preliminary study on 621 addictive subjects.

The interpersonal dependency inventory comprised three subscales called Emotional reliance of another person (ER), lack of social self confidence (LSS) and Assertion of autonomy (AUT). Several formula have been developed for deriving whole-scale scores. The aim of the study on 621 addictive subjects was to determine the best formula using the DSM-IV dependent personality disorder as gold standard. The formula 3 ER + LSS - AUT yielded the best values of sensitivity and specificity.

Adult↗

PubMed2002

[Alexithymia and alcohol dependence].

Alexithymia is a term introduced by Sifneos in 1973 to describe, initially in psychosomatic patients, the inability to recognize and to express emotions. Since 1973, alexithymia has been also described in alcohol dependence. A review of these studies is proposed with the results of our study from the INSERM network "Dependence". Prevalence of alexithymia is high in alcoholic patients, between 40 and 60%. Some authors have found that alexithymia predicted poor outcome in these patients. The distinction between primary and secondary alexithymia and the relationships between depression and alexithymia are complex. The psychodynamic hypothesis that alexithymia could hold a central position secondary to early dysfunction in the construction of the psychic and somatic self can be put forward. In some circumstances, regression to this position, even after transient addictive filling-in, could lead to essential depression and to psychosomatic disease.

Affective Symptoms↗

PubMedDate not supplied

Comorbidity of dependent personality disorder and separation anxiety disorder in addictive disorders and in healthy subjects.

The aim of the study was to determine the comorbidity of dependent personality disorder (DPD) and separation anxiety disorder (SAD) in large nonclinical and clinical samples. Using a cross-sectional method, the relationship between these disorders was studied in 784 healthy subjects and in 708 subjects presenting with various addictive behaviors. DPD was significantly associated with SAD in healthy subjects, alcoholics, drug abusers and anorectic and bulimic patients. The comorbidities of SAD and DPD suggest that specific therapeutic strategies could be discussed. Moreover, longitudinal studies are required to determine if SAD constitutes a risk factor for DPD.

Adolescent↗