Altered Neuromagnetic Activity in Persistent Postural-Perceptual Dizziness: A Multifrequency Magnetoencephalography Study.

Objective: The aim of our study was to investigate abnormal changes in brain activity in patients with persistent postural-perceptual dizziness (PPPD) using magnetoencephalography (MEG). Methods: Magnetoencephalography recordings from 18 PPPD patients and 18 healthy controls were analyzed to determine the source of brain activity in seven frequency ranges using accumulated source imaging (ASI). Results: Our study showed that significant changes in the patterns of localization in the temporal-parietal junction (TPJ) were observed at 1-4, 4-8, and 12-30 Hz in PPPD patients compared with healthy controls, and changes in the frontal cortex were found at 1-4, 80-250, and 250-500 Hz in PPPD patients compared with controls. The neuromagnetic activity in TPJ was observed increased significantly in 1-4 and 4-8 Hz, while the neuromagnetic activity in frontal cortex was found increased significantly in 1-4 Hz. In addition, the localized source strength in TPJ in 1-4 Hz was positively correlated with DHI score (r = 0.7085, p < 0.05), while the localized source strength in frontal cortex in 1-4 Hz was positively correlated with HAMA score (r = 0.5542, p < 0.05). Conclusion: Our results demonstrated that alterations in the TPJ and frontal cortex may play a critical role in the pathophysiological mechanism of PPPD. The neuromagnetic activity in TPJ may be related to dizziness symptom of PPPD patients, while the neuromagnetic activity in frontal lobe may be related to emotional symptoms of PPPD patients. In addition, frequency-dependent changes in neuromagnetic activity, especially neuromagnetic activity in low frequency bands, were involved in the pathophysiology of PPPD.

Impact of Antiepileptic Drugs on Cognition and Neuromagnetic Activity in Childhood Epilepsy With Centrotemporal Spikes: A Magnetoencephalography Study.

Objective: Childhood epilepsy with centrotemporal spikes (CECTS), the most common childhood epilepsy, still lacks longitudinal imaging studies involving antiepileptic drugs (AEDs). In order to examine the effect of AEDs on cognition and brain activity. We investigated the neuromagnetic activities and cognitive profile in children with CECTS before and after 1 year of treatment. Methods: Fifteen children with CECTS aged 6-12 years underwent high-sampling magnetoencephalography (MEG) recordings before treatment and at 1 year after treatment, and 12 completed the cognitive assessment (The Wechsler Intelligence Scale for Children). Next, magnetic source location and functional connectivity (FC) were investigated in order to characterize interictal neuromagnetic activity in the seven frequency sub-bands, including: delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), gamma (30-80 Hz), ripple (80-250 Hz), and fast ripple (250-500 Hz). Results: After 1 year of treatment, children with CECTS had increased scores on full-scale intelligence quotient, verbal comprehension index (VCI) and perceptual reasoning index (PRI). Alterations of neural activity occurred in specific frequency bands. Source location, in the 30-80 Hz frequency band, was significantly increased in the posterior cingulate cortex (PCC) after treatment. Moreover, FC analysis demonstrated that after treatment, the connectivity between the PCC and the medial frontal cortex (MFC) was enhanced in the 8-12 Hz frequency band. Additionally, the whole-brain network distribution was more dispersed in the 80-250 Hz frequency band. Conclusion: Intrinsic neural activity has frequency-dependent characteristic. AEDs have impact on regional activity and FC of the default mode network (DMN). Normalization of aberrant DMN in children with CECTS after treatment is likely the reason for improvement of cognitive function.

Pretreatment Source Location and Functional Connectivity Network Correlated With Therapy Response in Childhood Absence Epilepsy: A Magnetoencephalography Study.

Objective: This study aims to investigate the differences between antiepileptic drug (AED) responders and nonresponders among patients with childhood absence epilepsy (CAE) using magnetoencephalography (MEG) and to additionally evaluate whether the neuromagnetic signals of the brain neurons were correlated with the response to therapy. Methods: Twenty-four drug-naïve patients were subjected to MEG under six frequency bandwidths during ictal periods. The source location and functional connectivity were analyzed using accumulated source imaging and correlation analysis, respectively. All patients were treated with appropriate AED, at least 1 year after their MEG recordings, their outcome was assessed, and they were consequently divided into responders and nonresponders. Results: The source location of the nonresponders was mainly in the frontal cortex at a frequency range of 8-12 and 30-80 Hz, especially 8-12 Hz, while the source location of the nonresponders was mostly in the medial frontal cortex, which was chosen as the region of interest. The nonresponders showed strong positive local frontal connections and deficient anterior and posterior connections at 80-250 Hz. Conclusion: The frontal cortex and especially the medial frontal cortex at α band might be relevant to AED-nonresponsive CAE patients. The local frontal positive epileptic network at 80-250 Hz in our study might further reveal underlying cerebral abnormalities even before treatment in CAE patients, which could cause them to be nonresponsive to AED. One single mechanism cannot explain AED resistance; the nonresponders may represent a subgroup of CAE who is refractory to several antiepileptic drugs.

Changes of Ictal-Onset Epileptic Network Synchronicity in Childhood Absence Epilepsy: A Magnetoencephalography Study.

Objective: To further understand the mechanisms underlying epileptic network and the characteristics of individual specific network, we conducted a study on brain network by magnetoencephalography (MEG) focusing on patients with childhood absence epilepsy (CAE). Methods: The network connectivity of 22 patients was investigated with MEG at the source level. Network connectivity of spikes and slow waves was computed with accumulated source imaging (ASI) and correlation analysis. Time-frequency analysis was used to characterize the network changes during the ictal-onset period of each patient and the potential factors. Results: We found that spectral power increased at around 1 s and distributed at 2-4 Hz in all patients. Ictal spikes simultaneously showed elevation of network connectivity, predominantly excitatory connections, when generalized firing activity spread to the overall brain. High-frequency oscillations (HFOs) were prone to detect overexcited neuronal firing in certain focal areas. Conclusions: Personal network changes during ictal onset had unique features in the time range and parallel seizure rhythm uniformly in every patient. There was an important time point for generalized discharges of the epileptic network. Ictal spiking activity played an important role in the epileptic network synchronicity of childhood absence epilepsy. Frequency oscillations provided references for locating abnormal changes in neuromagnetic signals.

The relationship between neuromagnetic activity and cognitive function in benign childhood epilepsy with centrotemporal spikes.

PURPOSE: Our aim was to explore the pathophysiological mechanism of cognitive function changes in early untreated children with benign childhood epilepsy with centrotemporal spikes (BECTS). METHODS: Magnetoencephalography (MEG) was performed in 33 children with BECTS and 18 healthy children. Wechsler Intelligence Scale for Children, fourth edition (WISC-IV) was used to divide children with BECTS into two groups. Normal cognitive function was defined as a full-scale intelligence quotient (FSIQ) of >80, while decreased cognitive function was defined as a FSIQ of <80. Accumulated source imaging was used to evaluate the neuromagnetic source activity in multifrequency bands. RESULTS: Of the 33 patients with early untreated BECTS, a total of 17 had a FSIQ of <80 and 16 had FSIQ of >80. The course of epilepsy and number of seizures in the FSIQ <80 group were higher than that in the FSIQ >80 group. Our MEG results showed that in the 4-8 Hz frequency band, both patient groups had inactivation of the posterior cingulate cortex (PCC) region compared with the healthy control group. In the 30-80 Hz frequency band, the FSIQ <80 group showed inactivation of the PCC region compared with both the healthy control group and the FSIQ >80 group. In the 80-250 Hz frequency band, the FSIQ <80 group had inactivated of the medial frontal cortex (MFC) region compared with the healthy control group. In the 30-80 Hz frequency band, the strength of neuromagnetic source in patients with BECTS with FSIQ <80 was higher than that in the FSIQ >80 group and the healthy control group. CONCLUSIONS: The magnetic source inactivation of the MFC and PCC regions during the interictal time may be the reason for cognitive decline in early untreated children with BECTS. Children with BECTS with cognitive decline had a longer course of epilepsy and more seizures. The magnetic source localization in the 4-8 Hz frequency band may be a new imaging marker for the diagnosis of new BECTS.

Multifrequency Dynamics of Cortical Neuromagnetic Activity Underlying Seizure Termination in Absence Epilepsy.

PURPOSE: This study aimed to investigate the spectral and spatial signatures of neuromagnetic activity underlying the termination of absence seizures. METHODS: Magnetoencephalography (MEG) data were recorded from 18 drug-naive patients with childhood absence epilepsy (CAE). Accumulated source imaging (ASI) was used to analyze MEG data at the source level in seven frequency ranges: delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), gamma (30-80 Hz), ripple (80-250 Hz), and fast ripple (250-500 Hz). RESULT: In the 1-4, 4-8, and 8-12 Hz ranges, the magnetic source during seizure termination appeared to be consistent over the ictal period and was mainly localized in the frontal cortex (FC) and parieto-occipito-temporal junction (POT). In the 12-30 and 30-80 Hz ranges, a significant reduction in source activity was observed in the frontal lobe during seizure termination as well as a decrease in peak source strength. The ictal peak source strength in the 1-4 Hz range was negatively correlated with the ictal duration of the seizure, whereas in the 30-80 Hz range, it was positively correlated with the course of epilepsy. CONCLUSION: The termination of absence seizures is associated with a dynamic neuromagnetic process. Frequency-dependent changes in the FC were observed during seizure termination, which may be involved in the process of neural network interaction. Neuromagnetic activity in different frequency bands may play different roles in the pathophysiological mechanism during absence seizures.

[Comparison of Cookgas and Fastrach intubating laryngeal mask airway with fiberoptic bronchoscope in anticipated difficult airway management].

OBJECTIVE: To compare the clinical effectiveness of fiberoptic bronchoscope (FOB)-guided intubation through the Cookgas intubating laryngeal airway(CILA)and the Fastrach intubating laryngeal mask airway (FT-LMA) in the management of anticipated difficult airways. METHODS: Sixty patients with all three difficult intubation criterion (thyromental distance<60 mm, interincisor distance<35 mm, and Mallampati class 3 or 4) undergoing elective plastic surgery under general anesthesia were randomly allocated into CILA group (n=30) and FT-LMA group (n=30). After anesthesia being induced and CILA or FT-LMA being inserted, the patients were treated with FOB-guided intubation through CILA or FT-LMA. The success of the intubating laryngeal airway(ILA)insertion and FOB-guided intubation, the number of attempts, and the duration of the successful attempt were recorded. RESULTS: The ILA was inserted successfully in 30 patients from CILA group and 27 patients from FT-LMA group. Three failed cases in FT-LMA group were inserted successfully with CILA. In CILA group, the first FOB-guided intubation attempt succeeded in 26 patients, and 4 cases were intubated at the second attempt. In 27 patients of FT-LMA group, 20 cases were intubated successfully at the first attempt, 4 cases at the second attempt, and 3 cases failed; of these three failed patients, two patients were intubated smoothly with FOB through CILA at the first attempt, one was intubated by FOB via CILA at the second attempt. The duration of FT-LMA insertion [(35.3±12.8)s] was significantly longer when compared with CILA [(23.9±17.5)s] (P<0.05). However, the duration of FOB-guided intubation through CILA and FT-LMA [(48.6±13.5)s vs.(53.2±14.2)s] and the time of ILA removal [(40.4±10.2)s vs. (38.5±11.3)s] were not significantly different between these two groups (P>0.05). The adverse events during and after intubtion were not significantly different between these two groups. CONCLUSIONS: FOB-guided intubation through CILA and FT-LMA is safe and feasible for the management of anticipated difficult airways. However, in patients with severe scar contracture of face and neck and those with huge expander in neck, the CILA insertion and FOB-guided intubation via CILA is superior to FT-LMA.

CD105/Ki67 coexpression correlates with tumor progression and poor prognosis in epithelial ovarian cancer.

AIM: To analyze the expression patterns of CD105 and Ki67 in human epithelial ovarian cancer (EOC) and to evaluate the clinical significance of these two markers in the progression and prognosis in EOC. MATERIALS AND METHODS: The CD105 and Ki67 protein expression patterns in paraffin-embedded specimens gathered from 166 patients with EOC were detected by immunohistochemistry analysis. The association of CD105 and Ki67 protein expression with the prognosis in EOC was subsequently assessed. RESULTS: The CD105 and Ki67 proteins were positively expressed in 101/166 (60.8%) and 129/166 (77.7%) of EOC patients, respectively. The CD105 tumors are more likely to have higher tumor grade (P = 0.02). Patients with positive Ki67 staining are more likely to be at the advanced stage of the disease (P = 0.008). Marker CD105 was positively correlated with Ki67 (r = 0.66, P = 0.01). In addition, Ki67 (hazards ratio [HR], 4.8; confidence interval [CI], 1.2-16.6; P = 0.008) and CD105⁺ (HR, 4.1; CI, 1.0-15.2; P = 0.01) were both independent prognostic factors for poor overall survival in EOC patients. Furthermore, combined CD105/Ki67 expression was significantly related to unfavorable overall survival (HR, 16.6; CI, 1.2-128.9; P < 0.001). CONCLUSIONS: Our results suggest that the CD105 and Ki67 expressions might be involved in the progression of EOC and patient prognosis. A combined detection of CD105/Ki67 coexpression may benefit us in predicting the prognosis in EOC.

Expression level of wild-type survivin in gastric cancer is an independent predictor of survival.

AIM: Survivin is a novel antiapoptotic gene in which three splicing variants have been recently cloned and characterized. Survivin has been found to be abundantly expressed in a wide variety of human malignancies, whereas it is undetectable in normal adult tissues. We aimed to study the expression of three survivin splicing variants in gastric cancer, and to evaluate the prognostic significance of the expression of survivin variants in gastric cancer. METHODS: Real time quantitative RT-PCR was performed to analyze the expression of survivin variants in 79 paired tumors and normal gastric mucosa samples at the mRNA level. Proliferative and apoptotic activity was measured using Ki-67 immunohistochemical analysis and the TUNEL method, respectively. RESULTS: All the cases tested expressed wild-type survivin mRNA, which was not only the dominant transcript, but also a poor prognostic biomarker (P = 0.003). Non-antiapoptostic survivin-2B mRNA was correlated with tumor stage (P = 0.001), histological type (P = 0.004), and depth of tumor invasion (P = 0.041), while survivin-DeltaEx3 mRNA showed a significant association with apoptosis (P = 0.02). CONCLUSION: Wild-type survivin mRNA expression levels are of important prognostic value and significant participation of survivin-2B and survivin-DeltaEx3 is suggested in gastric cancer development.

[Elevated expression level of wild-type survivin in gastric cancer promotes in vitro docetaxel-resistance].

OBJECTIVE: To study the expression of three survivin splicing variants in gastric cancer and to evaluate the significant correlation between survivin variants' expression and chemoresistance in gastric cancer. METHODS: Real time quantitative RT-PCR was used to analyze the mRNA expression of survivin variants in 39 gastric tumor specimens resected during operation. The clinical resistance to anticancer agents [CDDP, MMC, 5-Fu, docetaxel (Taxotere TXT), and GEM] was analyzed by histoculture drug-response assay (HDRA). RESULTS: Among the 39 tumor samples, survivin expression was detected in all tumor samples (39/39); 79.5% (31/39) of the samples demonstrated survivin-2B expression and 66.7% (26/39) of the samples had survivin-Delta Ex3 expression. HDRA showed that the in vitro efficacy rates of CDDP, MMC, 5Fu, TXT, and GEM were 36.8% (14/38), 31.2% (10/32), 23.1% (9/39), 20.5% (8/39), and 12.5% (4/32) respectively, equivalent to the previous HDRA studies and historical clinical studies in gastric cancer patients. The expression rate of wild-type survivin was significantly higher in the group of chemoresistance to TXT than in the group sensitive to docetaxel (P = 0.021). CONCLUSION: Elevated expression level of wild-type survivin promotes docetaxel-resistance in patients with gastric cancer.