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Ca؉2 /calmodulin-dependent protein kinases (CaMKs) are activated upon binding of Ca ؉2 /calmodulin. To gain maximal activity, CaMK I and CaMK IV can be further phosphorylated by an upstream kinase, CaMK kinase (CaMKK). We previously isolated cDNA clones encoding human CaMKK ␤ isoforms that are heterogeneous in their 3-sequences (Hsu, L.-S., Tsou, A.-P., Chi, C.-W., Lee, C.-H., and Chen, J.-Y. (1998) J. Biomed. Sci. 5, 141-149). In the present study, we examined the genomic organization and transcription of the human CaMKK ␤ gene. The human CaMKK ␤ locus spans more than 40 kilobase pairs and maps to chromosome 12q24.2. It is organized into 18 exons and 17 introns that are flanked by typical splice donor and acceptor sequences. Two major species of transcripts, namely the ␤1 (5.6 kilobase pairs) and ␤2 (2.9 kilobase pairs), are generated through differential usage of polyadenylation sites located in the last and penultimate exons. Additional forms of CaMKK ␤ transcripts were also identified that resulted from alternative splicing of the internal exons 14 and/or 16. These isoforms display differential expression patterns in human tissues and tumor-derived cell lines. They also exhibit a distinct ability to undergo autophosphorylation and to phosphorylate the downstream kinases CaMK I and CaMK IV. The differential expression of CaMKK ␤ isoforms with distinct activity further suggests the complexity of the regulation of the CaMKK/CaMK cascade and an important role for CaMKK in the action of Ca ؉2 -mediated cellular responses.

GKS is an effective and safe treatment modality for CS hemangiomas with long-term treatment effect. Considering the high risks involved in microsurgery, GKS may serve as the primary treatment choice for CS hemangiomas.

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The operative findings and results of microvascular decompression (MVD) on 310 Chinese patients with hemifacial spasm are analyzed in this report. The operations were performed at the Neurological Institute of the Veterans General Hospital-Taipei between January 1983 and June 1990. The length of follow-up ranged from 6 months to 8 years (mean, 4.3 years); 273 patients (88%) had complete relief of spasm within 3 days after one MVD, and the remaining 37 patients (12%) showed no immediate postoperative improvement. Sixteen (5.2%) of these 37 initially unresponsive patients subsequently experienced complete relief, which occurred from 4 days to 22 months (median, 21 days) after one MVD; 13 others (4.2%) had complete relief immediately after the second MVD; another 3 (1%) had delayed complete relief 6, 9, and 11 months after the second MVD, respectively; and the remaining 5 (1.6%) only had delayed partial relief, which occurred 2 to 9 weeks after one MVD. Late recurrence occurred in three patients (1%). These immediate and long-term results lend support to the conclusion that the timing of reoperation can be postponed for a period of 3 to 4 weeks in the event of an initial failure to get improvement, and that a second MVD may be of value.

Hemangiopericytoma (HPC) is a rare tumor of the central nervous system and is usually found intracranially. Intraspinal HPCs are very rare and mostly involve the extradural bony structures. Primary intradural HPC has only been reported in 10 cases, all of which occurred in the extramedullary region. Intramedullary invasion has never been reported. Here, we describe a case of primary intradural HPC of the thoracic spine that presented initially with paresthesia and paraplegia of both legs. Magnetic resonance imaging of the thoracic spine showed an intradural dumbbell-shaped tumor at the T10 level. The initial impression was neurogenic tumor, meningioma, or metastasis. During operation, the tumor was found to have obvious intramedullary invasion. Gross-total removal was done, and the patient's neurological function improved; there was no recurrence at the 3-year follow-up. There is no consensus as to what constitutes the optimal treatment of HPC, but most neurosurgeons will advocate gross-total resection. A comparative analysis between intradural and extradural HPCs showed a higher chance of gross-total resection for intradural HPCs, while the recurrence rates showed no difference. The role of adjuvant radiotherapy remains uncertain. Due to the high risk of recurrence and metastasis of HPCs, close follow-up for a long period is mandatory.

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