Search

Glycogen synthase kinase-3 (GSK-3) mediates epidermal growth factor, insulin and Wnt signals to various downstream events such as glycogen metabolism, gene expression, proliferation and differentiation. We have isolated here a GSK-3β-interacting protein from a rat brain cDNA library using a yeast twohybrid method. This protein consists of 832 amino acids and possesses Regulators of G protein Signaling (RGS) and dishevelled (Dsh) homologous domains in its N- and C-terminal regions, respectively. The predicted amino acid sequence of this GSK-3β-interacting protein shows 94% identity with mouse Axin, which recently has been identified as a negative regulator of the Wnt signaling pathway; therefore, we termed this protein rAxin (rat Axin). rAxin interacted directly with, and was phosphorylated by, GSK-3β. rAxin also interacted directly with the armadillo repeats of β-catenin. The binding site of rAxin for GSK-3β was distinct from the β-catenin-binding site, and these three proteins formed a ternary complex. Furthermore, rAxin promoted GSK-3β-dependent phosphorylation of β-catenin. These results suggest that rAxin negatively regulates the Wnt signaling pathway by interacting with GSK-3β and β-catenin and mediating the signal from GSK-3β to β-catenin. [ABSTRACT FROM AUTHOR]

Snowboarding-related head injuries have become less common as the number of snowboarders has decreased;however, severe head injuries, such as acute subdural hematomas, occur every snowboarding season. We investigated the characteristics of cases of snowboarding-related acute subdural hematoma treated at our hospital. A total of 3,632 patients with snowboarding-related head injuries seen at our hospital between the 1995/96 and 2012/13 snowboarding seasons were enrolled in this study. Seventy-nine(2.2%)patients were diagnosed with acute subdural hematomas using computed tomography. We statistically analyzed the patient questionnaire responses, clinical records, and radiological findings. We compared the findings of the acute subdural hematoma(ASDH)group with those of the non-ASDH group. Among beginners, falling on a slope, incidents involving gentle slopes, and injuries of unknown origin were significantly more common in the ASDH group. On the other hand, among the intermediate snowboarders, incidents involving jumps, jump failure, and collisions with other snowboarders were more common in the non-ASDH group. Secondly, in an analysis involving subjects who had an ASDH, we compared the beginner group with the intermediate/advanced group. Falling on a slope, incidents involving gentle slopes, pure ASDH, diffuse brain swelling, and death were more common in the beginner group, and ASDH combined with contusions or subarachnoid hemorrhaging and incidents involving a jump were more common in the intermediate/advanced group. Finally, we summarized the cases of 10 subjects with an ASDH as well as diffuse brain swelling. Nine of the 10 patients died, 8 were first-timers or beginners, 6 had incidents involving flat or gentle slopes, and 5 had fallen on a slope. Snowboarding is a recreational sport;therefore, snowboarders must take responsibility for their actions. However, snowboarders, especially beginners, could decrease their risk of ASDH if they are informed about ASDH and take precautions to reduce their risk of falling on gentle slopes. Educational activities related to this topic should continue.

Object: To elucidate clinical aspects of ruptured aneurysms, we retrospectively investigated associations between risk factors and ruptured and unruptured cases during conservative management., Methods: Two hundred and twenty-nine patients with 291 unruptured cerebral aneurysms treated between 2000 and 2012 were analyzed. Mean duration of observation was 62 months (1183.4 person-years). We investigated the following six risk factors: history of subarachnoid hemorrhage;multiplicity;location of aneurysms;aneurysm size ≤5mm;bleb or irregular forms;and follow-up period <1 year., Results: Twenty-two aneurysms in 22 patients (19 women;86.4%) ruptured during this study. The annual rate of rupture was 1.86%. In ruptured cases, mean age was 66.7 years. According to univariate analysis, aneurysm size≥5mm(p=0.000), bleb or irregular form(p=0.006)and duration of observation<1 year (p =0.000) were significantly associated with aneurysmal rupture. In multivariate analysis of these factors, aneurysm size≥5mm(p =0.0188;odds ratio(OR), 3.4;95% confidence interval (CI), 1.2-9.7) and duration of observation<1 year (p=0.006;OR, 5.0;95% CI, 1.6-14.9) represented independent risk factors for aneurysm rupture., Conclusions: The results of this study were almost the same as those of the UCAS Japan study. In addition, duration of observation <1 year was a risk factor for aneurysm rupture. When we decide on surgical treatment after considering factors such as aneurysm size, form, and surgical risk, surgery should be performed as soon as possible.

A decreased intake of brightly colored vegetables results in increased levels of serum homocysteine, and homocysteinemia is associated with the progression of arteriosclerosis. Moreover, homocysteinemia is a known risk factor for cerebral infarction. Here, we report three cases wherein multiple simultaneous intracranial hemorrhages developed in the presence of homocysteinemia. The dietary habits of the patients involved indicated that decreased intake of brightly colored vegetables and the consequent progression of arteriosclerosis caused intracranial hemorrhage. Thus, in daily medical care, the measurement of serum homocysteine levels is useful for managing dietary habits and progression of arteriosclerosis.

We report a rare case of a meningioma causing acute hematoma. A 67-year-old woman presented with sudden headache. No evidence of trauma was seen. CT demonstrated a subdural hematoma in the convexity of the fronto-temporal lobe. Magnetic resonance imaging showed marked signal heterogeneity in the convexity of the frontal lobe. One week later, the patient underwent hematoma evacuation and tumor resection including the attached dura mater. The histological diagnosis was meningothelial meningioma. The clot was connected directly to the tumor and the origin of the subdural hematoma was identified as the meningioma. Postoperative course was uneventful, and the headache improved. Meningiomas have a relatively benign course but rarely present with hemorrhage. Surgical exploration is the effective and recommended treatment.

Infantile dural arteriovenous fistula is a rare cerebrovascular malformation carrying a poor prognosis with an anatomic cure of only 9%. Endovascular embolization is mainly selected to treat this entity, aiming to obtain normal development of the patients. We present a case of a 20-month-old girl with epilepsy. Digital subtraction angiography revealed a dural arteriovenous fistula involving the right transverse sinus. The arteriovenous fistula was fed by multiple dural branches from the middle meningeal, occipital, meningohypophyseal, and anteroinferior cerebellar arteries. The right transverse sinus was transvenously embolized with platinum coils. Although the shunt flow remained, the patient was liberated from epilepsy. Nine months later, the patient suffered from a recurrence of epilepsy. Digital subtraction angiography demonstrated some increase in shunt flow. Right middle meningeal, occipital, posterior deep temporal, and tentorial arteries were transarterially embolized using N-butyl cyanoacrylate, followed by complete surgical resection of the right transverse sinus. The shunt flow disappeared after surgery, and her epilepsy improved significantly. Our experience suggests that the combination of endovascular and surgical treatment is effective for recurrent infantile dural arteriovenous fistula.

We report a case of Bickerstaff's brainstem encephalitis (BBE) with positive findings on head MRI. Abnormal lesions on head MRI were detected in approximately 30% cases of BBE. An 81-year-old female presented with disturbance of consciousness (Japan Coma Scale 200), ophthalmoplegia (downward deviation) and tetraplegia. Cerebrospinal fluid examination revealed mild pleocytosis 244 cells in 3 microl of CSF with normal glycorrhachia. Head MRI showed high-intensity abnormalities extending over the brain stem. The patient was diagnosed with BBE. It was thought that her symptoms were believed to arise from the lesion in reticular formation, rostral interstitial nucleus of the medial longitudinal fasciculus, and the pyramidal tract. At discharged after 1 month, she had no sequela.