Simultaneous EEG,fMRI, and behavior in typical childhood absence seizures

Purpose: Absence seizures cause transient impairment of consciousness. Typical absence seizures occur in children, and are accompanied by 3–4‐Hz spike–wave discharges (SWDs) on electroencephalography (EEG). Prior EEG–functional magnetic resonance imaging (fMRI) studies of SWDs have shown a network of cortical and subcortical changes during these electrical events. However, fMRI during typical childhood absence seizures with confirmed impaired consciousness has not been previously investigated. Methods: We performed EEG‐fMRI with simultaneous behavioral testing in 37 children with typical childhood absence epilepsy (CAE). Attentional vigilance was evaluated by a continuous performance task (CPT), and simpler motor performance was evaluated by a repetitive tapping task (RTT). Results: SWD episodes were obtained during fMRI scanning from 9 patients among the 37 studied. fMRI signal increases during SWDs were observed in the thalamus, frontal cortex, primary visual, auditory, somatosensory, and motor cortex, and fMRI decreases were seen in the lateral and medial parietal cortex, cingulate gyrus, and basal ganglia. Omission error rate (missed targets) with SWDs during fMRI was 81% on CPT and 39% on RTT. For those seizure epochs during which CPT performance was impaired, fMRI changes were seen in cortical and subcortical structures typically involved in SWDs, whereas minimal changes were observed for the few epochs during which performance was spared. Discussion: These findings suggest that typical absence seizures involve a network of cortical–subcortical areas necessary for normal attention and primary information processing. Identification of this network may improve understanding of cognitive impairments in CAE, and may help guide development of new therapies for this disorder.     

A clinicopathological study of giant cell tumor of small bones

Background and purpose

Giant cell tumor (GCT) of the small bones (small-bone GCT) is usually rare and considered somewhat different from conventional GCT. The purpose of this study was to investigate and report the clinicopathological features of 11 cases with small-bone GCT.

Materials and methods

Patient information was obtained with the help of questionnaires. X-rays and paraffin blocks obtained from several institutions were clinically, radiographically, and histologically evaluated.

Results

Small-bone GCT was observed in younger patients compared to conventional GCT; 5 of the 11 (45%) patients were below 20 years of age, whereas the corresponding figure for all GCT patients is 16% in Japan. Excessive cortical bone expansion is a special feature. There were two cases of recurrence and one case of lung metastasis; the primary lesion was in the hand for all three cases. In contrast, no primary lesion of the foot recurred or metastasized. Varying degrees of positive p63 immunostaining were observed in all examined cases (n = 9) of small-bone GCT but were negative in case of giant cell reparative granuloma (GCRG) and solid variant of aneurysmal bone cyst (ABC). One case that demonstrated high-intensity positive staining had two episodes of recurrence.

Conclusion

Small-bone GCT tends to develop in younger patients than does conventional GCT. Primary GCTs of the hand may be biologically more aggressive than those of the feet. The p63 immunostaining may be useful not only for differential diagnosis but also for prognostication of small-bone GCT.     

PolyU tail of rho-independent terminator of bacterial small RNAs is essential for Hfq action

Major bacterial small RNAs (sRNAs) regulate the translation and stability of target mRNAs through base pairing with the help of the RNA chaperone Hfq. The Hfq-dependent sRNAs consist of three basic elements, mRNA base-pairing region, Hfq-binding site, and rho-independent terminator. Although the base-pairing region and the terminator are well documented in many sRNAs, the Hfq-binding site is less well-defined except that Hfq binds RNA with a preference for AU-rich sequences. Here, we performed mutational and biochemical studies to define the sRNA site required for Hfq action using SgrS as a model sRNA. We found that shortening terminator polyU tail eliminates the ability of SgrS to bind to Hfq and to silence ptsG mRNA. We also demonstrate that the SgrS terminator can be replaced with any foreign rho-independent terminators possessing a polyU tail longer than 8 without losing the ability to silence ptsG mRNA in an Hfq-dependent manner. Moreover, we found that shortening the terminator polyU tail of several other sRNAs also eliminates the ability to bind to Hfq and to regulate target mRNAs. We conclude that the polyU tail of sRNAs is essential for Hfq action in general. The data also indicate that the terminator polyU tail plays a role in Hfq-dependent stabilization of sRNAs.     

Small intestinal follicular lymphoma with multiple tumor formations diagnosed by double-balloon enteroscopy

Follicular lymphoma of the small intestine remains relatively rare, especially in its early stage. Recently, double-balloon endoscopy has enabled observation of the entire small intestine. We describe a case of follicular lymphoma with multiple lesions in the small intestine detected by double-balloon endoscopy. The patient showed multiple whitish granules in descending portion of the duodenum on screening esophagogastroduodenoscopy, which were subsequently diagnosed as follicular lymphoma by immunohistochemistry. Endoscopic examination of the entire small intestine revealed multiple follicular lymphoma tumors in inferior portion of the duodenum and in the proximal jejunum. Double-balloon endoscopy is useful for evaluating tumor distribution of follicular lymphoma.     

An EEG (electroencephalogram) recording system with carbon wire electrodes for simultaneous EEG-fMRI (functional magnetic resonance imaging) recording

Simultaneous EEG-fMRI (Electroencephalography-functional Magnetic Resonance Imaging) recording provides a means for acquiring high temporal resolution electrophysiological data and high spatial resolution metabolic data of the brain in the same experimental runs. Carbon wire electrodes (not metallic EEG electrodes with carbon wire leads) are suitable for simultaneous EEG-fMRI recording, because they cause less RF (radio-frequency) heating and susceptibility artifacts than metallic electrodes. These characteristics are especially desirable for recording the EEG in high field MRI scanners. Carbon wire electrodes are also comfortable to wear during long recording sessions. However, carbon electrodes have high electrode-electrolyte potentials compared to widely used Ag/AgCl (silver/silver chloride) electrodes, which may cause slow voltage drifts. This paper introduces a prototype EEG recording system with carbon wire electrodes and a circuit that suppresses the slow voltage drift. The system was tested for the voltage drift, RF heating, susceptibility artifact, and impedance, and was also evaluated in a simultaneous ERP (event-related potential)-fMRI experiment.     

A new surgical technique for management of conjunctivochalasis

PURPOSE: To present a new surgical technique for severe, symptomatic conjunctivochalasis and our hypothesis of the pathogenesis of this condition. METHODS: Six eyes of three patients with conjunctivochalasis (average age +/-SD, 70.0 +/- 9.6 years; range, 56-78 years) were treated with a conjunctival fixation to sclera with three 6-0 Vicryl (Johnson & Johnson, New Brunswick, New Jersey) stitches. RESULTS: With a mean follow-up period of 209.5 days (range, 181-219 days), we achieved successful treatment in all eyes, with no recurrence of conjunctival folds. CONCLUSION: We successfully treated conjunctivochalasis with conjunctival fixation to sclera, which strongly suggests that conjuctival folds are caused by the folding and the elevating of loosely adherent bulbar conjunctiva of the lower eyelid.