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Background: Auditory steady-state response (ASSR) induced by repetitive auditory stimulus is commonly used for audiometric testing. ASSR can be measured using electro-encephalography (EEG) and magnetoencephalography (MEG), referred to as steady-state auditory evoked potential (SSAEP) and steady-state auditory evoked field (SSAEF), respectively. However, the signal level of SSAEP and SSAEF are weak so that signal processing technique is required to increase its signal-to-noise ratio. In this study, a complementary ensemble empirical mode decomposition (CEEMD)-based approach is proposed in MEG study and the extraction of SSAEF has been demonstrated in normal subjects and tinnitus patients. Methods: The CEEMD utilizes noise assisted data analysis (NADA) approach by adding positive and negative noise to decompose MEG signals into complementary intrinsic mode functions (IMF). Ten subjects (five normal and five tinnitus patients) were studied. The auditory stimulus was designed as 1 kHz carrier frequency with 37 Hz modulation frequency. Two channels in the vicinities of right and left temporal areas were chosen as channel-of-interests (COI) and decomposed into IMFs. The spatial distribution of each IMF was correlated with a pair of left- and right-hemisphere spatial templates, designed from each subject's N100m responses in pure-tone auditory stimulation. IMFs with spatial distributions highly correlated with spatial templates were identified using K-means and those SSAEF-related IMFs were used to reconstruct noise-suppressed SSAEFs. Results: The current strengths estimated from CEEMD processed SSAEF showed neural activities greater or comparable to those processed by conventional filtering method. Both the normal and tinnitus groups showed the phenomenon of right-hemisphere dominance. The mean current strengths of auditory-induced neural activities in tinnitus group were larger than the normal group. Conclusions: The present study proposes an effective method for SSAEF extraction. The enhanced SSAEF in tinnitus group echoes the decreased inhibition in tinnitus's central auditory structures as reported in previous studies. [ABSTRACT FROM AUTHOR]

Background: Auditory steady-state response (ASSR) induced by repetitive auditory stimulus is commonly used for audiometric testing. ASSR can be measured using electro-encephalography (EEG) and magnetoencephalography (MEG), referred to as steady-state auditory evoked potential (SSAEP) and steady-state auditory evoked field (SSAEF), respectively. However, the signal level of SSAEP and SSAEF are weak so that signal processing technique is required to increase its signal-to-noise ratio. In this study, a complementary ensemble empirical mode decomposition (CEEMD)-based approach is proposed in MEG study and the extraction of SSAEF has been demonstrated in normal subjects and tinnitus patients. Methods: The CEEMD utilizes noise assisted data analysis (NADA) approach by adding positive and negative noise to decompose MEG signals into complementary intrinsic mode functions (IMF). Ten subjects (five normal and five tinnitus patients) were studied. The auditory stimulus was designed as 1 kHz carrier frequency with 37 Hz modulation frequency. Two channels in the vicinities of right and left temporal areas were chosen as channel-of-interests (COI) and decomposed into IMFs. The spatial distribution of each IMF was correlated with a pair of left- and right-hemisphere spatial templates, designed from each subject's N100m responses in pure-tone auditory stimulation. IMFs with spatial distributions highly correlated with spatial templates were identified using K-means and those SSAEF-related IMFs were used to reconstruct noise-suppressed SSAEFs. Results: The current strengths estimated from CEEMD processed SSAEF showed neural activities greater or comparable to those processed by conventional filtering method. Both the normal and tinnitus groups showed the phenomenon of right-hemisphere dominance. The mean current strengths of auditory-induced neural activities in tinnitus group were larger than the normal group. Conclusions: The present study proposes an effective method for SSAEF extraction. The enhanced SSAEF in tinnitus group echoes the decreased inhibition in tinnitus's central auditory structures as reported in previous studies. [ABSTRACT FROM AUTHOR]

Background: Auditory steady-state response (ASSR) induced by repetitive auditory stimulus is commonly used for audiometric testing. ASSR can be measured using electro-encephalography (EEG) and magnetoencephalography (MEG), referred to as steady-state auditory evoked potential (SSAEP) and steady-state auditory evoked field (SSAEF), respectively. However, the signal level of SSAEP and SSAEF are weak so that signal processing technique is required to increase its signal-to-noise ratio. In this study, a complementary ensemble empirical mode decomposition (CEEMD)-based approach is proposed in MEG study and the extraction of SSAEF has been demonstrated in normal subjects and tinnitus patients. Methods: The CEEMD utilizes noise assisted data analysis (NADA) approach by adding positive and negative noise to decompose MEG signals into complementary intrinsic mode functions (IMF). Ten subjects (five normal and five tinnitus patients) were studied. The auditory stimulus was designed as 1 kHz carrier frequency with 37 Hz modulation frequency. Two channels in the vicinities of right and left temporal areas were chosen as channel-of-interests (COI) and decomposed into IMFs. The spatial distribution of each IMF was correlated with a pair of left- and right-hemisphere spatial templates, designed from each subject’s N100m responses in pure-tone auditory stimulation. IMFs with spatial distributions highly correlated with spatial templates were identified using K-means and those SSAEF-related IMFs were used to reconstruct noise-suppressed SSAEFs. Results: The current strengths estimated from CEEMD processed SSAEF showed neural activities greater or comparable to those processed by conventional filtering method. Both the normal and tinnitus groups showed the phenomenon of right-hemisphere dominance. The mean current strengths of auditory-induced neural activities in tinnitus group were larger than the normal group. Conclusions: The present study proposes an effective method for SSAEF extraction. The enhanced SSAEF in tinnitus group echoes the decreased inhibition in tinnitus’s central auditory structures as reported in previous studies. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) leads to important and deleterious neuroinflammation, as evidenced by indicators such as edema, cytokine production, induction of nitric oxide synthase, and leukocyte infiltration. After TBI, cerebral vascular endothelial cells play a crucial role in the pathogenesis of inflammation. In our previous study, we proved that simvastatin could attenuate cerebral vascular endothelial inflammatory response in a rat traumatic brain injury. This purpose of this study was to determine whether simvastatin combined with an antioxidant could produce the same effect or greater and to examine affected surrogate biomarkers for the neuroinflammation after traumatic brain injury in rat. In our study, cortical contusions were induced, and the effect of acute and continuous treatment of simvastatin and vitamin C on behavior and inflammation in adult rats following experimental TBI was evaluated. The results demonstrated that simvastatin combined with an antioxidant could provide neuroprotection and it may be attributed to a dampening of cerebral vascular endothelial inflammatory response. [ABSTRACT FROM AUTHOR]

Background: Duroplasty has been widely used in cranial surgery when primary closure is not possible. The goal is to protect the cerebrum and thereby ensure that complications were as few as possible. We reviewed a single-institution experience with a variety of dural substitutes in craniotomy and analyzed the risk factors for duroplasty-associated hemorrhagic complications. Patients and Methods: Patients who received dural replacement after craniotomy or craniectomy between July 2004 and June 2009 were enrolled into this study. Medical records were reviewed for diagnosis, procedure, and type of dural replacement. Clinical courses were reviewed for hemorrhagic complications, including subdural hematoma, extradural hematoma, and subarachnoid hemorrhage. Logistic regression models were used to analyzed the risk factors of duroplasty-associated hemorrhagic complications. Results: Two hundred and twelve patients were included in the study. Overall, the hemorrhagic complication rate was 4.7% (10 patients). Complications were seen for microporous polyester urethane, expanded polytetrafluoroethylene monolayer, polyester silicone, and Biomesh in 4.1%, 0%, and 38.5% of patients, respectively. Patients who received duroplasty with Biomesh had a higher hemorrhagic complication rate with the odds ratio of 24.75 (95% confidence interval, 4.33-141.41) in comparison of those with microporous polyester urethane group after adjusting for individual confounders. Conclusion: The increased risk of hemorrhagic complications associated with craniotomy is modified by choice of dural replacement. Our results could assist clinicians in their decision-making with respect to the optimal timing for synthetic dural substitutes in patients with tumor infiltration of the patient's dura, severe brain swelling in traumatic brain injury, or a result of shrinkage from exposure and electrocautery. [ABSTRACT FROM AUTHOR]

Pluchea indica (L.) Less. is a perennial plant known for its versatile uses in traditional medicine. Previous findings have shown that the extracts of Pluchea indica possess significant anti-inflammatory, anti-ulcer and anti-tuberculosis activity. The aim of this study was to demonstrate the anticancer activity of the hexane fraction of P. indica root extract (H-PIRE) in human glioblastoma cells using flow cytometric and western blot analysis. The results shoewd that, H-PIRE suppressed the growth of glioblastoma cells in a dose-dependent manner. H-PIRE treatment markedly decreased the population of cells in S and G2/M phases. The significant upregulation of acidic vesicular organelle (AVO) was detected during H-PIRE treatment. The expression levels of microtubule-associated light chain 3-II (LC3-II) protein, phosphorylated JNK and phosphorylated p38 were significantly increased, confirming the occurrence of autophagy during the process. Finally, the combination treatment of H-PIRE and LY294002, a pan PI3K inhibitor, further decreased cell viability, suggesting an additive anticancer effect. Taken together, our results suggest that H-PIRE suppresses the proliferation of glioblastoma cells by inducing cell cycle arrest and autophagy. [ABSTRACT FROM AUTHOR]

The present study was performed to ascertain whether sacroiliac joint (SIJ) pain represents a potential source of pain in patients who have undergone lumbar or lumbosacral fusions. Prospective cohort study. Between June 2007 and June 2009, 130 patients who underwent lumbar or lumbosacral fusions were evaluated for SIJ pain. Fifty-two patients for whom positive findings were obtained on at least three of the provocating tests for SIJ pain were selected to receive dual diagnostic blocks. A positive response was defined as characteristic pain reduction of 75% for 1-4 hours following the SIJ blocks. Predictive factors for a positive response to the SIJ blocks were also investigated. Among the 52 patients, 21 were considered to have SIJ pain on the basis of two positive responses to diagnostic blocks. Univariate analysis revealed that the predictive factors related to positive responses were unilateral pain ( P = 0.002), more than three positive responses to provocating maneuvers ( P = 0.02), and postoperative pain with characteristics different from those of preoperative pain ( P = 0.04). SIJ pain is a potential source of pain after lumbar and lumbosacral fusion surgeries. Provocating SIJ maneuvers represent reliable tests for SIJ pain. The characteristics of postoperative SIJ pain frequently differ from those of preoperative pain. [ABSTRACT FROM AUTHOR]

To compare the efficacy of percutaneous vertebroplasty (PV) with conservative therapy for patients with acute vertebral compression fractures. Prospective, nonrandomized, comparison study. The efficacy of PV has not been well established because there have been few comparative studies with conservatively treated control groups. Fifty-five consecutive patients (8 men and 47 women, age 47-94) with osteoporosis and symptomatic acute vertebral compression fractures were enrolled. Thirty-two patients received PV, whereas 23 received conservative therapy. Changes in pain intensity, physical functioning, and pain medication requirement were evaluated. Both PV and conservative therapy provided pain reduction ( P < 0.001), improvements in physical functioning ( P < 0.001), and decreased medication ( P < 0.001). Reductions in visual analogue pain scores were more significant in the vertebroplasty group at 1 ( P < 0.001) and 4 weeks ( P < 0.001) but not at 12 months. Improvements in physical functioning were significant at 1 ( P < 0.001) and 4 weeks ( P < 0.001). Medication requirements were lower in the vertebroplasty group at all three time points. Pain relief, physical functioning improvement, and medication requirement after vertebroplasty are immediately and significantly better when compared with conservative therapy. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2010) 114, 237–246. Previously we demonstrated benefits of inhibiting the extracellular signal-regulated kinases 1/2 (ERK1/2) signaling pathway in spinal cord ischemia/reperfusion (I/R) injury. To further identify the underlying mechanisms, we investigated the impact of ERK inhibition on apoptosis and cellular protective mechanisms against cell death. Spinal cord I/R injury induced ERK1/2 phosphorylation, followed by neuronal loss through caspase 3-mediated apoptosis. Pre-treatment with U0126, a specific inhibitor of MAPK/ERK kinases 1/2 (MEK1/2), inhibited ERK1/2 phosphorylation, and significantly attenuated apoptosis and increased neuronal survival. MEK/ERK inhibition also induced I-κB phosphorylation and enhanced nuclear factor (NF)-κB/DNA binding activity, leading to expression of cellular inhibitors of apoptosis protein 2 (c-IAP2), a known nuclear factor-κB (NF-κB)-regulated endogenous anti-apoptotic molecule. Pyrrolidine dithiocarbamate, an NF-κB inhibitor, by blocking I-κB phosphorylation, NF-κB activation, and c-IAP2 synthesis, abolished the protective effects of U0126. The MEK/ERK pathway appears to mediate cellular death following I/R injury. The U0126 neuroprotection appears related to NF-κB-regulated transcriptional control of c-IAP2. MEK/ERK inhibition at the initial stage of I/R injury may cause changes in c-IAP2 gene expression or c-IAP2/caspase 3 interactions, resulting in long lasting therapeutic effects. Future research should focus on the possible cross-talk between the MEK/ERK pathway and the NF-κB transcriptional cascade. [ABSTRACT FROM AUTHOR]