Right orbitofrontal tumor with pedophilia symptom and constructional apraxia sign

BACKGROUND: Orbitofrontal abnormalities are associated with poor impulse control, altered sexual behavior, and sociopathy. OBJECTIVE: To describe a patient with acquired pedophilia and a right orbitofrontal tumor who was unable to inhibit sexual urges despite preserved moral knowledge. DESIGN: Case report. RESULTS: The patient displayed impulsive sexual behavior with pedophilia, marked constructional apraxia, and agraphia. The behavioral symptoms and constructional deficits, including agraphia, resolved following tumor resection. CONCLUSIONS: For patients with acquired sociopathy and paraphilia, an orbitofrontal localization requires consideration. This case further illustrates that constructional apraxia can arise from right prefrontal lobe dysfunction. Agraphia may represent a manifestation of constructional apraxia in the absence of aphasia and ideomotor apraxia.     

Comparison of electrodiagnostic abnormalities and criteria in a cohort of patients with chronic inflammatory demyelinating polyneuropathy

BACKGROUND: Current electrodiagnostic criteria for chronic inflammatory demyelinating polyneuropathy (CIDP) are research oriented favoring specificity over sensitivity. Application of such criteria in clinical practice may miss the diagnosis in potentially treatable patients. OBJECTIVES: To analyze the electrophysiologic abnormalities in a cohort of patients with clinically defined CIDP, to compare these data with published electrodiagnostic criteria, and to identify a set of abnormalities that is shared by all patients with CIDP. DESIGN: Retrospective medical record review. SETTING: Academically based neuromuscular clinic.Patients Fifteen patients with clinically diagnosed relapsing sensorimotor CIDP. INTERVENTIONS: Administration of intravenous immunoglobulin or prednisone. MAIN OUTCOME MEASURES: Electrodiagnostic studies. RESULTS: All patients had electrodiagnostic abnormalities in at least 3 nerves with possible partial conduction block or demyelinating range abnormalities in at least 1 nerve. The diagnostic sensitivities of 5 published CIDP criteria were as follows: the Ad Hoc Subcommittee of the American Academy of Neurology AIDS Task Force (40%), Saperstein et al (47%), Nicolas et al (53%), Hughes et al for the Inflammatory Neuropathy Cause and Treatment Group (60%), and Thaisetthawatkul et al (70%). CONCLUSIONS: Current electrodiagnostic criteria for CIDP are insensitive and may fail to diagnose the condition in a substantial number of patients. More inclusive criteria that allow identification of patients in routine clinical practice are needed.     

Metabotropic glutamate receptor regulation of neuronal cell death

The metabotropic glutamate receptors (mGluRs) are a family of glutamate-sensitive receptors that regulate neuronal function separately from the ionotropic glutamate receptors. By coupling to guanosine nucleotide-binding proteins (G proteins), mGluRs are able to regulate neuronal injury and survival, likely through a series of downstream protein kinase and cysteine protease signaling pathways that affect mitochondrial regulated programmed cell death (PCD). The physiological relevance of this system is supported by evidence that mGluRs are associated with cell survival in several central nervous system neurodegenerative diseases. Evidence is presented that mGluRs are also able to prevent PCD in the peripheral nervous system, and that this may provide a novel mechanism for treatment of diabetic neuropathy. In dorsal root ganglion (DRG) neurons, a high glucose load increases generation of reactive oxygen species (ROS), destabilizes the inner mitochondrial membrane potential (Deltapsi(M)), induces cytochrome c release from the mitochondrial intermembrane space, and induces downstream activation of caspases. In high-glucose conditions, the group II metabotropic glutamate agonist N-acetylaspartylglutamate (NAAG) blocks caspase activation and is completely reversed by the mGluR3 antagonist (S)-alpha-ethylglutamic acid (EGLU). Furthermore, the direct mGluR3 agonist (2R,4R)-4-aminopyrrolidine-2, 4-dicarboxylate (APDC) prevents induction of ROS. Together these findings are consistent with an emerging concept that mGluRs may protect against cellular injury by regulating oxidative stress in the neuron. More complete understanding of the complex PCD regulatory pathways mediated by mGluRs will provide new therapeutic approaches for the treatment of a wide variety of neurodegenerative diseases.