Functional Consequences of Mutations in Postsynaptic Scaffolding Proteins and Relevance to Psychiatric Disorders

The Prader–Willi syndrome (PWS), a rare multisystem genetic disease, leads to severe disabilities, such as morbid obesity, endocrine dysfunctions, psychiatric disorders, and social disturbances. We explored the whole brain of patients with PWS to detect abnormalities that might explain the behavioral and social disturbances, as well as the psychiatric disorders of these patients. Nine patients with PWS (six males, three females; mean age 16.4 years) underwent a positron emission tomography (PET) scan with H215O as a tracer to measure regional cerebral blood flow (rCBF). The images were compared with those acquired from nine controls (six males, three females; mean age 21.2 years). A morphologic magnetic resonance imaging (MRI) was also performed in PWS patients, and their cognitive and behavioral skills were assessed with Wechsler Intelligence Scale for Children III and the Child Behavior Check List (CBCL). The MRI images showed no evident anatomic abnormalities, whereas PET scans revealed hypoperfused brain regions in PWS patients compared with controls, particularly in the anterior cingulum and superior temporal regions. We observed a significant relationship ( P<0.05) between rCBF in the hypoperfused regions and CBCL scores. The functional consequences of these perfusion abnormalities in specific brain regions might explain the behavioral and social problems observed in these individuals.

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Distribution of Extrasynaptic NMDA Receptors on Neurons

The Scientific World JOURNAL ◽

10.1100/2012/267120 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 59

Author(s):

Ronald S. Petralia

Keyword(s):

Nervous System ◽

Nmda Receptor ◽

Nmda Receptors ◽

Cell Damage ◽

Receptor Activation ◽

Negative Influence ◽

Scaffolding Proteins ◽

Functional Consequences ◽

Receptor Clusters ◽

Nmda Receptor Activation

NMDA receptors are found in both synaptic and extrasynaptic locations on neurons. NMDA receptors also can be found on neurons in early stages prior to synaptogenesis, where they may be involved in migration and differentiation. Extrasynaptic NMDA receptors typically are associated with contacts with adjacent processes such as axons and glia. Extrasynaptic NMDA receptor clusters vary in size and may form associations with scaffolding proteins such as PSD-95 and SAP102. The best-characterized extrasynaptic NMDA receptors contain NR1 and NR2B subunits. Extrasynaptic NMDA receptors may be activated by glutamate spillover from synapses or from ectopic release of glutamate. Consequently, extrasynaptic NMDA receptor activation may occur under different circumstances than that for synaptic NMDA receptors, indicating different functional consequences for the neuron. In some cases, activation of extrasynaptic NMDA receptors may have a negative influence on the neuron, leading to cell damage and death, as may occur in some major diseases of the nervous system.

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What's in a model? Network models as tools instead of representations of what psychiatric disorders really are

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001206 ◽

2019 ◽

Vol 42 ◽

Cited By ~ 2

Author(s):

Hanna M. van Loo ◽

Jan-Willem Romeijn

Keyword(s):

Psychiatric Disorders ◽

Network Models ◽

Model Network

AbstractNetwork models block reductionism about psychiatric disorders only if models are interpreted in a realist manner – that is, taken to represent “what psychiatric disorders really are.” A flexible and more instrumentalist view of models is needed to improve our understanding of the heterogeneity and multifactorial character of psychiatric disorders.

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Applications of RTMS in psychiatric disorders

Electroencephalography and Clinical Neurophysiology ◽

10.1016/s0013-4694(97)88126-x ◽

1997 ◽

Vol 103 (1) ◽

pp. 49

Author(s):

E Wassermann

Keyword(s):

Psychiatric Disorders

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Psychiatric Disorders Inherited Separately From Atopy

Skin & Allergy News ◽

10.1016/s0037-6337(05)70608-2 ◽

2005 ◽

Vol 36 (2) ◽

pp. 63

Author(s):

DAMIAN MCNAMARA

Keyword(s):

Psychiatric Disorders

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Suicide in Nógrád County, Hungary, 1970-1994

Crisis ◽

10.1027//0227-5910.20.2.64 ◽

1999 ◽

Vol 20 (2) ◽

pp. 64-70 ◽

Cited By ~ 5

Author(s):

Tamás Zonda

Keyword(s):

High Risk ◽

Psychiatric Disorders ◽

Suicide Rate ◽

Risk Groups ◽

The Elderly ◽

Female Ratio ◽

Suicide Notes ◽

Suicidal Intention ◽

Male Female Ratio

The author examined completed suicides occurring over a period of 25 years in a county of Hungary with a traditionally low (relatively speaking) suicide rate of 25.8. The rates are clearly higher in villages than in the towns. The male/female ratio was close to 4:1, among elderly though only 1.5:1. The high risk groups are the elderly, divorced, and widowed. Violent methods are chosen in 66.4% of the cases. The rates are particularly high in the period April-July. Prior communication of suicidal intention was revealed in 16.3% of all cases. Previous attempts had been undertaken by 17%, which in turn means that 83% of suicides were first attempts. In our material 10% the victims left suicide notes. Psychiatric disorders were present in 60.1% of the cases, and severe, multiple somatic illnesses (including malignomas) were present in 8.8%. The majority of the data resemble those found in the literature.

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Sati

Crisis ◽

10.1027/0227-5910.26.2.73 ◽

2005 ◽

Vol 26 (2) ◽

pp. 73-77 ◽

Cited By ~ 15

Author(s):

Dinesh Bhugra

Keyword(s):

Mental Illness ◽

Psychiatric Disorders ◽

Indian Subcontinent ◽

Cultural Factors ◽

Role Expectations ◽

Prevention Strategies ◽

Social Causation ◽

Gender Role Expectations ◽

Good Wife ◽

And Gender

Abstract. Sati as an act of ritual suicide has been reported from the Indian subcontinent, especially among the Hindus, for several centuries. Although legally proscribed, these acts occur even now in modern India. The principle behind such acts has been put forward as the principle of good wife. There is little evidence to suggest that women who commit this act suffer from a formal mental illness. Cultural factors and gender role expectations play a significant role in the act and its consequences. Using recent examples, this paper illustrates the cultural factors, which may be seen as contributing to the act of suicide. Other factors embedded in the act also emphasize that not all suicides have underlying psychiatric disorders and clinicians must take social causation into account while preparing any prevention strategies.

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