[A study of reduction of NF 2 protein, mRNA and loss of 22 q in sporadic meningiomas].

Neurofibromatosis 2(NF 2) is one of the tumor suppressor genes, and its disorder has been reported in sporadic meningiomas. We investigated some reduction of expression of NF 2 protein and mRNA in 33 sporadic meningiomas, using immunohistochemistry and in situ hybridization, respectively. Seventeen of 33 (51.5%) meningiomas demonstrated significantly reduced or absent NF 2 protein expression. Its mRNA was also reduced or absent in 11 of 24(45.8%) meningiomas, and some statistically significant correlation was shown between reductions of NF 2 protein and its mRNA. Furthermore, we studied about loss of 22 q in 5 meningiomas with fluorescence in situ hybridization. In the cases with reduction of NF 2 protein and/or mRNA, 22 q telomere signals were observed as loss of heterozygosity. On the other hand, in the cases with expression of NF 2 protein and mRNA, 22 q telomere signals were normal. In conclusion, reduction or absence of NF 2 protein and mRNA may play an important role in the tumorigenesis of about half number of sporadic meningiomas.

[Anesthetic management of a patient with osteogenesis imperfecta congenita].

We experienced anesthetic management of three cases of osteogenesis imperfecta. Case 1: A 2-year-old boy weighing 8.6 kg was premedicated with chloral hydrate 250 mg intrarectally, but he was very excited on arrival at the operating room. Induction of anesthesia was performed by intramuscular injection of ketamine 40 mg. Case 2: A 4-year-old girl underwent three surgeries (2 osteomies and 1 intramedullary nailing of the tibias) during the past two years. On the second and third procedures, marked hyperthermia (over 39.2 degrees C as rectal temperature) developed during halothane (1-2%) and enflurane (1.5-2.5%) anesthesia. However, on the first surgery, hyperthermia did not occur under combined light halothane (0.3-0.5%) anesthesia with caudal epidural block. Case 3: A 14-year-old female underwent osteotomy of the radius under brachial plexus block without any anesthetic complications. In conclusion, anesthetic considerations for children with this disease are as follows; 1) It is necessary to premedicate to provide good preoperative sedation. 2) Care should be taken to use inhaled anesthetic agents (halothane and enflurane) because of tendency to develop abnormal hyperthermia. 3) It is desirable to use regional anesthesia.