Hyponatremia with Loss of High Signal Intensity in the Posterior Pituitary Lobe on T1-weighted Magnetic Resonance Imaging.

Herein, we report on an 82-year-old woman who presented with anorexia. The patient had hyponatremia with preserved urinary osmotic pressure. T1-weighted magnetic resonance imaging (MRI) showed a lack of high signal intensity (SI) in the posterior pituitary lobe. Based on the patient's high levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP), heart failure was suspected. The heart failure may have caused arginine vasopressin (AVP) secretion. The depletion of AVP secretory granules may therefore cause the posterior pituitary gland to disappear on T1-weighted MRI.

Diabetic Hemichorea-hemiballism after Prompt Improvement in Hyperglycemia.

We herein report a case of hemichorea-hemiballism in an 85-year-old man diagnosed with diabetes at 76 years of age. After a one-year interruption in treatment, he was treated with a low-calorie diet, linagliptin, and nateglinide. Over 51 days, his HbA1c level decreased from 15.8% to 7.7%. After a prompt improvement in his hyperglycemia, he began experiencing involuntary movements in the right upper and lower extremities. T1-weighted magnetic resonance imaging showed a high signal intensity in the left lens nucleus. The patient was diagnosed with diabetic hemichorea-hemiballism and received haloperidol (1 mg/day) as treatment.

Segmental copy-number gain within the region of isopentenyl diphosphate isomerase genes in sporadic amyotrophic lateral sclerosis.

AIMS: Sporadic amyotrophic lateral sclerosis (SALS) seems to be a multifactorial disease, the pathogenesis of which may involve both genetic and environmental factors. The present study aims at identifying a possible genetic change that confers risk for SALS. METHODS: We performed whole-genome screening of a copy-number variation (CNV) using a CNV beadchip, followed by real-time quantitative polymerase chain reaction (qPCR) and region-targeted high-density oligonucleotide tiling microarray. RESULTS: Within the 40-kb region on 10p15.3 subtelomere, which harbours two genes encoding isopentenyl diphosphate isomerase 1 (IDI1) and IDI2, we found a segmental copy-number gain in a large proportion of SALS patients. qPCR analysis demonstrated the copy-number gain in 46 out of 83 SALS patients, as compared with 10 out of 99 controls (p=4.86×10(-11), Odds Ratio 10.8); subsequent tiling microarray validated qPCR results and elucidated the fine structure of segmental gains. CONCLUSIONS: A segmental copy-number gain in the IDI1/IDI2 gene region may play a significant role in the pathogenesis of SALS.

A case of reversible encephalopathy accompanied by demyelination occurring after ingestion of Sugihiratake mushrooms.

Recently, an outbreak of acute encephalopathy associated with Sugihiratake mushroom ingestion has been reported in northern Japan. Patients with chronic kidney diseases are thought to be at risk for severe encephalopathy following Sugihiratake mushroom ingestion. We report a case of encephalopathy associated with Sugihiratake mushroom ingestion in a patient with diabetic nephropathy. Brain magnetic resonance imaging showed discriminative intensity in the medial temporal lobe, claustrum, and insula cortex bilaterally. Cerebrospinal fluid examination revealed mildly elevated protein and marked elevation of myelin basic protein without pleocytosis. Twenty-five days after admission, these signal-intensity changes had markedly improved, and the patient was discharged without sequelae. Although the exact mechanism of this acute encephalopathy remains undetermined, demyelination is believed to be a possible associated pathological change. In cases of encephalopathy of undetermined cause with distinct magnetic resonance findings, Sugihiratake mushroom intoxication should be considered in areas where ingestion of this mushroom is common.

The role of G-protein-coupled receptor kinase 5 in pathogenesis of sporadic Parkinson's disease.

Sporadic Parkinson's disease (sPD) is a common neurodegenerative disorder, characterized by selective degeneration of dopaminergic neurons in the substantia nigra. Although the pathogenesis of the disease remains undetermined, phosphorylation of alpha-synuclein and its oligomer formation seem to play a key role. However, the protein kinase(s) involved in the phosphorylation in the pathogenesis of sPD has not been identified. Here, we found that G-protein-coupled receptor kinase 5 (GRK5) accumulated in Lewy bodies and colocalized with alpha-synuclein in the pathological structures of the brains of sPD patients. In cotransfected cells, GRK5 phosphorylated Ser-129 of alpha-synuclein at the plasma membrane and induced translocation of phosphorylated alpha-synuclein to the perikaryal area. GRK5-catalyzed phosphorylation also promoted the formation of soluble oligomers and aggregates of alpha-synuclein. Genetic association study revealed haplotypic association of the GRK5 gene with susceptibility to sPD. The haplotype contained two functional single-nucleotide polymorphisms, m22.1 and m24, in introns of the GRK5 gene, which bound to YY1 (Yin Yang-1) and CREB-1 (cAMP response element-binding protein 1), respectively, and increased transcriptional activity of the reporter gene. The results suggest that phosphorylation of alpha-synuclein by GRK5 plays a crucial role in the pathogenesis of sPD.

[A case of non-herpetic acute limbic encephalitis associated with a type-2 adenovirus infection].

This is a report of a 31-year-old woman with non-herpetic acute limbic encephalitis following a type-2 adenovirus infection. The patient was admitted to a hospital with high fever, severe liver dysfunction, and thrombocytopenia. Six days after admission, she became afebrile, and her liver dysfunction was normalized by conservative therapy. However, the patient started to experience generalized seizures that developed into status epileptics. The patient was then transferred to a referred hospital. Brain MR images revealed faint high-signal intensity in the bilateral limbic systems on FLAIR images. A CSF examination indicated mild pleocytosis. These findings suggested acute limbic encephalitis, which may have been mediated by an autoimmune reaction following some viral infection. Thus, steroid pulse therapy was started on the day of admission. The patient's condition, including the seizures and disturbances involving consciousness, improved gradually. The patient was discharged from the hospital in one month while still experiencing mild memory disturbances. Three months after onset of the illness, a T1-weighted MR image showed a linear high-signal intensity in the hippocampi, which indicated focal necrosis. Six months after onset, the patient's memory disturbance had been improved (her MMSE score was 28/30 points). We investigated the titers of many viruses that are known to cause liver dysfunction and found that a titer of the type-2 adenovirus was significantly elevated within three weeks. Although the anti-voltage-gated potassium channel (VGKC) antibody was not detected in the patient's serum, it seems that the autoimmune reaction after the type-2 adenovirus infection may have caused the acute limbic encephalitis.