Background-Diacylglycerol (DAG) is a lipid second messenger that transiently accumulates in cells stimulated by endothelin-1 (ET-1) and other G␣q protein-coupled receptor agonists. Diacylglycerol kinase (DGK) is thought to be an enzyme that controls the cellular levels of DAG by converting it to phosphatidic acid; however, the functional role of DGK has not been examined in cardiomyocytes. Because DGK inactivates DAG, a strong activator of protein kinase C (PKC), we hypothesized that DGK inhibited ET-1-induced activation of a DAG-PKC signaling cascade and subsequent cardiomyocyte hypertrophy. Methods and Results-Real-time reverse transcription-polymerase chain reaction demonstrated a significant increase of DGK-mRNA by ET-1 in cardiomyocytes. To determine the functional role of DGK-, we overexpressed DGK-in cardiomyocytes using a recombinant adenovirus encoding rat DGK-(Ad-DGK). ET-1-induced translocation of PKC-⑀ was blocked by Ad-DGK (PϽ0.01). Ad-DGK also inhibited ET-1-induced activation of extracellular signal-regulated kinase (PϽ0.01). Luciferase reporter assay revealed that ET-1-mediated increase of activator protein-1 (AP1) DNA-binding activity was significantly inhibited by DGK-(PϽ0.01). In cardiomyocytes transfected with DGK-, ET-1 failed to cause gene induction of atrial natriuretic factor, increases in [
Intracranial capillary hemangiomas are very rare, though several spinal capillary hemangiomas have recently been reported. We report here a case of intracranial capillary hemangioma with multiple cysts and review the current literature of similar cases. A 4-month-old girl was referred to our hospital for treatment of hydrocephalus and a cerebellar mass lesion. She presented with hemangiomas distributed widely over the body, as well as disseminated hemangiomas in the pleura, liver, spleen, pancreas, kidneys and vagina. Pathological examination of the specimen from the vagina confirmed the diagnosis of a capillary hemangioma made at another hospital. Radiological examination of the brain revealed a cystic mass lesion in the left cerebellar hemisphere with subsequent obstructive hydrocephalus. The cysts extended upward into the bilateral ventricle. Following neuroendoscopic fenestration of the cysts, resection of the left cerebellar mass was performed. Histological examination of the lesion demonstrated similarly sized capillaries, and the pathological diagnosis was confirmed as capillary hemangioma. There was no recurrence postoperatively. Our patient was treated successfully by surgical resection and neuroendoscopic procedures. Surgical intervention may therefore be indicated in intracranial capillary hemangiomas.
Biliary atresia (BA) is a rare disease, characterized by progressive and obliterative cholangiopathy, and is one of the major causes of secondary vitamin K deficiency in infancy. We describe 15 infants (10 female, 5 male) with BA, presenting with intracranial hemorrhage (ICH), including 10 subdural hemorrhages, 4 subarachnoid hemorrhages, 2 intraventricular hemorrhages, and 1 intraparenchymal hemorrhage. The age at onset of ICH ranged from 26 to 79 (mean 54.2) days. Eight patients underwent successful surgical evacuation of ICH, following administration of vitamin K. All 15 patients underwent Kasai portoenterostomy for BA 8–30 days after onset. During a mean follow-up period of 86.8 (range 2–352) months, 4 patients died of liver failure despite lack of neurological sequelae. Two patients underwent living-related donor and 1 patient living-unrelated donor liver transplantation. Only 2 patients suffered neurological signs and symptoms, including mental retardation and epilepsy, whereas 3 were noted to have temporary hemiparesis which recovered completely during the follow-up period. The possibility of BA should be considered in the treatment of ICH due to vitamin K deficiency, since it is reported to be one of the major causes of secondary vitamin K deficiency. Urgent surgical intervention for ICH can be performed successfully following sufficient administration of vitamin K or fresh frozen human plasma. Moreover, early performance of Kasai portoenterostomy is possible even for patients who have undergone craniotomy.
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