Influence of ascorbic acid on bonding of peroxide-affected dentin and 4-META/MMA-TBB resin

The purpose of this study was to evaluate the tensile bond strength (TBS) to peroxide-exposed dentin. Furthermore, the effect of ascorbic acid (AA) on the bond strength of peroxide-exposed dentin was investigated. Extracted bovine dentin was exposed to 10% carbamide peroxide, 30% hydrogen peroxide, or distilled water for 30 min, then treated with 10% AA (0, 30, 90, and 180 min), and conditioned with 10% citric acid/3% ferric chloride. The polymethyl-methacrylate (PMMA) rod was bonded to the treated bovine dentin with 4-META/MMA-TBB resin. A minidumbbell-shaped bonded specimen was prepared from these bonded assemblies and the TBS was tested. The fractured surfaces were also observed with a scanning electron microscope. Exposure to peroxide before bonding significantly reduced bond strength. The application of AA to the peroxide-exposed dentin increased bond strength. On the other hand, an adverse effect of AA was found in distilled water-affected dentin. Extended resin fibers were partially seen in the peroxide-exposed dentin. In conclusion, peroxide reduced the bond strength, and the stronger the oxidation, the weaker the obtained bond. Antioxidation with AA recovered the bond strength, and this effect increased the longer the AA was applied.K. Yazaki was formerly affiliated with Department of Pharmacology, Tokyo Dental College, 1-2-2, Masago, Mihama-ku, Chiba 261-8502, Japan. He is now in private practice.     

Familial cases of atypical clinical features genetically diagnosed as LEOPARD syndrome (multiple lentigines syndrome)

Five familial cases exhibited ephelides-like multiple lentigines, and we examined three of them, a mother and two sons. All three patients presented with small dark-brown maculae on the face and neck and electrocardiographic abnormalities. These findings sufficed to fulfill the criteria for LEOPARD syndrome (multiple lentigines syndrome), although they lacked five of seven major clinical features. However, the family members presented with a webbed neck and pectus excavatum, which are more frequently seen in Turner or Noonan syndrome. Histological examination of the lentigines revealed slightly elongated rete ridges, a hyperpigmented basal layer, and melanophages in the papillary dermis. Direct sequencing of the patients' genomic DNA revealed that all three had a consistent missense mutation [c.1403C > T (p.T468M)] in the PTPN11 gene, confirming LEOPARD syndrome with an atypical phenotype. It was suggested that LEOPARD syndrome shows a diverse phenotype but its diagnosis can be verified by mutation analysis.     

Extrapancreatic solid pseudopapillary tumor: case report and review of the literature

A 22-year-old woman complained of abdominal discomfort. Ultrasonography, computed tomography, and an endocrinologic work-up revealed a 7-cm nonfunctional tumor at the left adrenal lesion. A transumbilical laparo-endoscopic single-site adrenalectomy was successfully completed in 166?min. The postoperative period was uneventful. The pathologic examination confirmed the solid pseudopapillary tumor occurred in the retroperitoneum. There are only five previous reports of extrapancreatic solid pseudopapillary tumors. In this case, the tumor was separated from the pancreas and no ectopic pancreas was histologically observed. To the best of our knowledge, this case is the first report of a solid pseudopapillary tumor of the retroperitoneum.     

Extragonadal seminoma presenting as a large mass in the pelvic cavity without c-kit-activating mutations

Extragonadal germ cell tumors are relatively rare tumors, which usually occur in the mediastinum or retroperitoneum. In this report, we present a case of primary seminoma arising in the pelvic cavity. A 58-year-old man with urinary retention and abdominal distension was admitted to our hospital. Computed tomography and magnetic resonance imaging demonstrated a large mass in the pelvic cavity. Histological examination of the specimens obtained by open biopsy revealed seminomatous malignant cells. Immunohistochemical studies detected vimentin, placental alkaline phosphatase and c-kit. Taking these results together with the patient's other clinical manifestations, this case was diagnosed as extragonadal seminoma without c-kit-activating mutations, and chemotherapy followed by radiation therapy was successful. Primary seminoma in the pelvic cavity is extremely rare, but should be considered a cause of pelvic mass formation.     

Single and multiple clusters of magnetoencephalographic dipoles in neocortical epilepsy: significance in characterizing the epileptogenic zone

PURPOSE: To characterize the epileptogenic zone in neocortical epilepsy (NE) by using magnetoencephalography (MEG). METHODS: We defined and compared locations of single and multiple clusters of equivalent current dipoles (ECDs) for interictal spikes with MRI findings, ictal-onset zones (IOZs) from subdural electroencephalography (SDEEG), resected areas, and postsurgical outcomes of 20 patients who underwent cortical resection for medically intractable NE. RESULTS: Fourteen patients had single clusters; six had multiple clusters. Overlap of clusters and IOZs defined group A (nine patients), in which a single cluster coincided with the IOZ; group B1 (four patients), in which a single cluster was within or partially overlapped the IOZ; group B2 (five patients), in which multiple-cluster sections overlapped IOZs; group C (two patients; one single; one multiple), in which no overlap was seen. More single clusters (nine of 14) than multiple clusters (none of six) coincided with the IOZ (p = 0.014). More patients with single clusters (10 of 14) than patients with multiple clusters (one of six) had seizure-free outcomes (p = 0.049). Eight of nine patients in group A, versus three of 11 in groups B1, B2, and C, achieved seizure-free outcomes (p = 0.0098). Correlations between MRI findings and postsurgical outcomes were not statistically significant; eight of 13 patients with single lesions, one of four with no lesions, and two of three with multifocal lesions had seizure-free outcomes. CONCLUSIONS: In neocortical epilepsy, MEG ECD clusters correlated with SDEEG IOZs. Single clusters indicated discrete epileptogenic zones that required complete resection for seizure-free outcome. Multiple clusters necessitated that the multiple or extensive epileptogenic zones be completely identified and delineated by SDEEG.     

Magnetoencephalography in patients with tuberous sclerosis and localization-related epilepsy

PURPOSE: To clarify the usefulness of magnetoencephalography (MEG) for diagnosis of the spatial relations between spike foci and suspicious epileptogenic tubers on MRI in patients with tuberous sclerosis (TS) and to compare MEG spike foci with single-photon emission computed tomography (SPECT) findings. METHODS: We analyzed magnetic fields of epileptic spike discharges in 15 patients with TS and localization-related epilepsy (LRE) by using MEG (a whole-head 204-channel magnetometer system). We investigated the spatial relation between the equivalent current dipoles (ECDs) of interictal spike discharges and visible cortical tubers on MRI. We also compared results of MEG and MRI with SPECT findings. RESULTS: MEG detected a cluster of ECDs around one cortical tuber in six of 15 patients and clusters of ECDs around two cortical tubers in five patients. Interictal SPECT was disappointing in detection of epileptic foci in TS. However, MEG spike foci showed spatial consistency with ictal hyperperfusion areas in two patients. Three patients with single ECD clusters underwent surgical treatment: two have been seizure free, and one has obtained seizure reduction of >90%. CONCLUSIONS: ECDs were located around visible tuber nodules. MEG enabled precise localization of the epileptic foci and provided crucial information for surgical treatment in patients with TS and partial epilepsy. TS patients showing a single ECD cluster on MEG may be appropriate candidates for surgical treatment.