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Journal Article 2008; 29(4): 405-409 PubMed PMID: 18766157 Citation  Keywords:  Autistic Disorder:physiopathology, Electroencephalography, Epilepsy:physiopathology, Humans,.   

: Autism is associated with a high frequency of epileptiform EEG abnormalities (prevalence range 10.3-72.4%) and epilepsy (prevalence range 0-44.5%). A significant subgroup of autistic children (20-49%) experience autistic regression. The relationship among EEG abnormalities, epilepsy, and regression in autistic patients is not yet well understood. In this review, the current knowledge of the relationship is summarized. The evidence from clinical studies does not support the view that EEG abnormalities play a role in autistic regression. The majority of studies also failed to find any significant relationship between epilepsy and autistic regression. However, some results indicated that the higher the prevalence of epilepsy in the sample, the greater the probability of there being a significant association between epilepsy and autistic regression. Further research on the topic is needed....

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Journal Article 2008; 29(4): 552-557 PubMed PMID: 18766156 Citation  Keywords:  Analgesics, Opioid:agonists, Animals, Hyperalgesia:chemically induced, Male, Pain:chemically induced, Pain Threshold:drug effects, Rats, Rats, Wistar, Selenium Compounds:metabolism, Vincristine:adverse effects,.   

PURPOSE: Effect of organoselenium compound (selol), on antinociceptive action of opioid agonists in vincristine neuropathic pain model was investigated.

METHODS: The changes in pain thresholds were determined using mechanical stimuli--the modification of the classic paw withdrawal test described by Randall-Selitto.

RESULTS: Daily administration of VIN (70 microg/kg, iv) resulted in progressive decrease of pain threshold. Neither morphine, fentanyl nor buprenorphine administered alone in 5 consecutive days modified the vincristine-induced hyperalgesia, whereas selol slightly increased the nociceptive threshold. Co-administration of selol with opioids markedly enhanced the analgesic activity of all three investigated compounds.

CONCLUSIONS: Therefore, concomitant administration of selenium and opioids may be beneficial in terminal neoplastic states....

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Journal Article 2008; 29(4): 438-442 PubMed PMID: 18766153 Citation  Keywords:  Animals, Antibodies, Monoclonal:metabolism, Cerebral Ventricles:anatomy & histology, Choroid Plexus:cytology, Epithelial Cells:cytology, Female, Flow Cytometry, P-Glycoprotein:metabolism, Sheep,.   

OBJECTIVES: Previous studies in the female sheep have shown that photoperiod modulates the passage of sex steroids between the blood and the cerebrospinal fluid (CSF) and have suggested the involvement of efflux transport. The objective of the present work was to assess the presence of P-glycoprotein (Pgp), which could be responsible for this transport at the level of the choroid plexuses (CP).

METHODS: We used flow cytometry and the UIC2 monoclonal antibody against Pgp, to demonstrate the presence of Pgp in the epithelial cell fraction isolated from the sheep choroid plexuses (CPEC). Thanks to the size of the brain structures in sheep, we analyse separately the CP from 4th ventricle (4V) and the CP from the lateral ventricle (LV).

RESULTS: In the whole population isolated from the CP, the 4V contained a higher percentage of living, epithelial cells than the LV. The immunoreactive cells to the UIC2 antibody i.e. bearing activated form of Pgp, represented 26.8% of the CPEC in the 4V, and 39.3% in the LV (P<0.05).

CONCLUSION: Pgp is expressed in the CPEC from the sheep. Differences in the expression of Pgp between CPEC from LV and 4V might suggest in vivo functional differences between LV and 4V CP in sheep....

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Journal Article 2008; 29(4): 467-474 PubMed PMID: 18766152 Citation  Keywords:  Affect:physiology, Aged, Amygdala:anatomy & histology, Cerebral Cortex:anatomy & histology, Cognition:physiology, Estrogens:blood, Female, Fluorodeoxyglucose F18:metabolism, Humans, Menopause:physiology, Middle Aged, Nerve Net:physiology, Positron-Emissio.   

OBJECTIVES: 1.) Expand the scope of neuroendocrine applications of functional neuroimaging techniques. 2.) Compare the covariance of amygdalar activity with that of the rest of the brain during pre- and post-menopausal levels of estrogen (E2). Based on the distribution of cortical E2 receptors and the neocortical regions where E2 has been shown to preferentially accumulate, we predict that E2 infusion will increase covariance of amygdalar activity with that of the temporal and frontal cortices.

DESIGN: This basic physiology study employed a within-subject design. All participants were post-menopausal women (n =7). Analysis of covariance between whole brain and amygdalar regional cerebral glucose consumption (CMRglc) was conducted in a voxel-wise manner by means of the basic regression option in SPM2 and was applied to FDG-PET scans acquired at baseline and after a 24 hour graded E2 infusion.

SETTING: An academic medical center; Massachusetts General Hospital, Boston, Massachusetts.

RESULTS: E2 levels (mean +/- sem) were significantly greater at 24 hours (257.9 pg/mL +/- 29.7) than at 0 hours (28.1 pg/mL +/- 3.4). Right amygdalar CMRglc showed a significant covariance with activity of three different regions of the temporal cortex during E2 infusion, but none at baseline. In addition, right amygdalar CMRglc covaried with that of the right medial and superior frontal gyri only during E2 infusion.

CONCLUSIONS: In addition to suggesting changes in amygdalar-cortical network connectivity as a result of short-term E2 exposure, these analyses provide evidence that basic neuroendocrine research may benefit from further use of FDG-PET and other functional neuroimaging modalities for network level analyses....

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Journal Article 2008; 29(4): 410-420 PubMed PMID: 18766151 Citation  Keywords:  Alzheimer Disease:drug therapy, Amyloid beta-Peptides:metabolism, Animals, Anti-Inflammatory Agents:therapeutic use, Anti-Inflammatory Agents, Non-Steroidal:therapeutic use, Antioxidants:therapeutic use, Cannabinoids:therapeutic use, Glucocorticoids:thera.   

: Alzheimer's disease (AD) is a serious neurodegenerative disease of aging. Recent projections of the dramatic increase in AD incidence worldwide by 2050 reveal its magnitude as a world-wide health crisis and underscore the urgent need to understand the etiology of AD in order to develop therapeutic interventions. A popular debate among scientists has traditionally pitted those in support of Beta amyloid protein as a causative factor ("Baptists") against others who implicate tau hyperphosphorylation ("Tauists"). Considering the significance of Beta amyloid protein and hyperphosphorlyated tau protein aggregates in AD pathology, this article delves into the nature of inflammation associated with these aggregates. Aspects of inflammation focus on microglia, resident immune cells of the CNS that are activated during AD inflammation and are known to play a significant role in pathogenesis. This article discusses the role of microglia, inflammation, and the immune response as a middle ground in the debate between the "Tauists" and the "Baptists" respective positions. It explores recent advances in immunotherapy and supports continued research in and use of immunosuppressive regimens as potential therapeutic interventions for AD....

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Journal Article 2008; 29(4): 507-511 PubMed PMID: 18766150 Citation  Keywords:  Animals, Behavior, Animal:physiology, Chickens, Female, Learning:physiology, Mothers, Neuropsychological Tests, Odorants, Placebos, Social Isolation, Stress, Psychological,.   

: A synthetic analogue of a mother-hen odour named MHUSA (Mother Hen Uropygial Secretion Analogue) reduces stress-related behaviour in the chicken. We hypothesize that MHUSA may have an attractant effect on chicks. In order to test this, 30 chicks were individually exposed to MHUSA, placebo or neutral when self isolated in a straight shuttle box. The location of the chicks within the test chamber was recorded with 360 consecutive scan-sampled images. During the first three minutes immediately after introduction to the test area chicks spent more time in the neutral zone (p<0.05). However, taking the results from the total observation period, chicks spent more time in the MHUSA and placebo zones combined than in the neutral zone (p=0.07). They were more often observed in the MHUSA zone compared to the placebo zone (p<0.05). These results suggest that during the first three minutes in the shuttle, individuals were adapting to their new environment. After this period, chicks directed themselves towards specific local stimuli, as they tried to reach their group or something that resembled it. After a stressor was introduced, we observed a return to the same situation as during the first three minutes of the test, with chicks returning to the neutral zone, suggesting that the chick had its confidence in the environment. Three main conclusions may be drawn. Firstly, MHUSA has an attractant effect on naïve chicks. Secondly, it appears to play a role in the reaction of chicks faced with a stressful event, and finally, the reaction to MHUSA seems innate and does not require previous experience....

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Journal Article 2008; 29(4): 512-517 PubMed PMID: 18766147 Citation  Keywords:  Autistic Disorder:physiopathology, Child, Child, Preschool, Electroencephalography, Humans, Intellectual Disability:physiopathology, Polysomnography, Sleep:physiology,.   

OBJECTIVES: Autism is a severe neurodevelopmental disorder with a high rate of epilepsy and subclinical epileptiform activity. High physical connectivity on a microcolumnar level leading to epileptiform activity and low functional informational connectivity are assumed in autism. The aim of this study was to investigate nonlinear EEG brain dynamics in terms of synchronization in a group of children with autism spectrum disorders compared to a control group. We expected a lower degree of synchronization in autistic subjects.

METHODS: The autistic group consisted of 27 patients with autism spectrum disorders diagnosed according to ICD-10. The mean age of the sample was 7.1 (SD 3.6) years, 14 of them were mentally retarded. Normal EEG was found in 9 patients, epileptiform EEG in 18 autistic patients. Four patients had a history of epileptic seizures, fully compensated in long term. The control group consisted of 20 children (mean age of 8.4, SD 2.3 years) with normal intelligence, without an epileptic history, investigated within the frame of the research program for cochlear implantation. They had normal neurological examination and suffered from perceptive deafness. Normal EEG was found in 17 of the control subjects, epileptiform EEG was in 3 control subjects. We analyzed night sleep EEG recordings from 10 channels (F3, F4, F7, F8, C3, C4, T3, T4, P3 and P4) with the inclusion of sleep stages NREM 2, 3 and 4 in the subsequent analyses. Coarse-grained entropy information rates between neighbouring electrodes were computed, expressing the synchronization between 11 selected electrode couples.

RESULTS: Synchronization was significantly lower in the autistic group in all three examined NREM stages even when age and intelligence were taken into account as covariates.

CONCLUSIONS: The results of the study confirmed the validity of the underconnectivity model in autism....

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Journal Article 2008; 29(4): 547-551 PubMed PMID: 18766146 Citation  Keywords:  Animals, Female, Male, Neuronal Plasticity:physiology, Neurons:cytology, Oxytocin:metabolism, Paraventricular Hypothalamic Nucleus:cytology, Rats, Restraint, Physical, Rodentia, Stress, Psychological,.   

OBJECTIVES AND METHODS: The presence of oxytocin (OT) and its putative participation to the phenotypic plasticity of CRH neurones in the stressed jerboa was investigated. We analysed by immunocytochemistry the OT expression within the hypothalamic parvicellular paraventricular nucleus (pPVN) of male jerboas submitted to an acute immobilization (30 min).

RESULTS: OT presence was clearly demonstrated in the pPVN of the jerboa and no significant difference in the number of OT immunolabeled cells was observed whatever the experimental conditions. Interestingly, CRH-immunoreactive neurons coexpressed OT within cell bodies and terminals in a similar way both in control and stressed animals. The level of coexpression was regionally heterogeneous and was not sensitive to the stress immobilization.

CONCLUSION: The present data reveal for the first time the occurrence of OT in hypothalamic pPVN neurons of the jerboa. Moreover, this OT expression level does not change upon an acute immobilization stress. These new data, coupled together with our previous work in the jerboa, incontestably establish a clear dichotomy between a stress-responsive CRH/CCK system and a stress non-responsive OT/VP system in the pPVN....

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