Upregulation of EphA4 deteriorate brain damage by shifting microglia M1-polarization via NF-κB signaling after focal cerebral ischemia in rats.

Ischemic stroke is the main reason of disability and mortality in many countries, and currently has limited treatments. The post-stroke inflammation characterized with microglia activation and polarization has been regarded as a promising therapeutic target for ischemic stroke. After ischemia, the activated microglia polarize to classical (M1) phenotype or alternative (M2) phenotype and exhibit biphasic function. Promoting microglia phenotype shift from deleterious M1 phenotype to neuroprotective M2 phenotype will be promising in stroke treatment. Increasing evidence indicates that the erythropoietin-producing human hepatocellular (Eph) receptor A4 (EphA4), a kind of abundant Eph receptor, distributes mainly in neuron and participates in multiple links of pathological changes after ischemia. This paper discussed the hypothesis that EphA4 receptor could affect ischemic brain injury through EphA4/ephrin bidirectional signaling between neuron and microglia, and then explored its underlying mechanisms. We manipulated EphA4/ephrin signaling with either EphA4 overexpression lentiviral vectors or the short hairpin RNA (shRNA) to upregulate or knock down neuronal EphA4 expression. NF-κB inhibitor pyrrolidine dithiocarbamate ammonium salt (PDTC) was applied to block NF-κB pathway. According to the experimental results, upregulated neuronal EphA4 induced by ischemia deteriorated neurological function as well as brain damage by shifting microglia M1-polarization via promoting NF-κB signaling.

Ataxic Severity Is Positively Correlated With Fatigue in Spinocerebellar Ataxia Type 3 Patients.

Background: Spinocerebellar ataxia type 3 (SCA3) is an inherited form of ataxia that leads to progressive neurodegeneration. Fatigue is a common non-motor symptom in SCA3 and other neurodegenerative diseases, such as Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). Although risk factors to fatigue in these diseases have been thoroughly studied, whether or not fatigue can affect clinical phenotypes has yet to be investigated. Methods: Ninety-one molecularly confirmed SCA3 patients and 85 age- and sex-matched controls were recruited for this study. The level of fatigue was measured using the 14-item Fatigue Scale (FS-14), and the risk factors to fatigue and how fatigue correlates with clinical phenotypes were studied using multivariable linear regression models. Results: We found that the severity was significantly higher in the SCA3 group than in the control group (9.30 ± 3.04% vs. 3.94 ± 2.66, P = 0.000). Daytime somnolence (ß = 0.209, P = 0.002), severity of ataxia (ß = 0.081, P = 0.006), and poor sleep quality (ß = 0.187, P = 0.037) were found to have a positive relationship with fatigue. Although fatigue had no relationship with age at onset or ataxic progression, we found that it did have a positive relationship with the severity of ataxia (ß = 7.009, P = 0.014). Conclusions: The high level of fatigue and the impact of fatigue on the clinical manifestation of SCA3 patients suggest that fatigue plays a large role in the pathogenesis of SCA3, thus demonstrating the need for intervention and treatment options in this patient cohort.

Neuronal EphA4 Regulates OGD/R-Induced Apoptosis by Promoting Alternative Activation of Microglia.

Accumulating evidence indicates that post-injury inflammation characterized by activated microglia contributes much to the neuropathology of ischemic injury. Several studies have demonstrated that microglia exhibit two entirely different functional activation states, referred to as classically activated (M1) and alternatively activated (M2) phenotype. Promoting microglial phenotype to switch from M1 dominant to M2 dominant might be a promising approach for handling ischemic injury. However, the comprehensive mechanism that underlines microglia polarization in ischemic brain remains unclear. Neuronal erythropoietin-producing human hepatocellular carcinoma cell receptor 4 (EphA4), the richest Eph receptor in the central nervous system (CNS), upregulate after ischemia and may have the potential to regulate microglia activation. We hypothesized that modulating EphA4/ephrin signaling could affect ischemic injury through controlling microglia polarization. We therefore knocked down neuronal EphA4 with short hairpin RNA (shRNA) and determined the role of EphA4/ephrin signaling in oxygen-glucose deprivation and reperfusion (OGD/R)-induced injury. We found that EphA4 shRNA treatment attenuated OGD/R-induced apoptosis and microglia proliferation. Neuronal EphA4 knockdown also promoted microglial M2 polarization, which reduced pro-inflammatory mediators and released anti-inflammatory cytokines as well as neurotrophic factors. We further revealed that EphA4 shRNA treatment functioned through RhoA/Rho-associated kinase 2 (ROCK2) signaling, a key mediator of microglia alternative activation. Together, these data suggested that blockage of EphA4/ephrin signaling between neuron and microglia decreased OGD/R-induced injury by promoting alternative activation of microglia via RhoA/ROCK2 signaling.

Roles of Eph/ephrin bidirectional signaling during injury and recovery of the central nervous system.

Multiple cellular components, including neuronal, glial and endothelial cells, are involved in the sophisticated pathological processes following central nervous system injury. The pathological process cannot reduce damage or improve functional recovery by merely targeting the molecular mechanisms of neuronal cell death after central nerve system injuries. Eph receptors and ephrin ligands have drawn wide attention since the discovery of their extensive distribution and unique bidirectional signaling between astrocytes and neurons. The roles of Eph/ephrin bidirectional signaling in the developmental processes have been reported in previous research. Recent observations suggest that Eph/ephrin bidirectional signaling continues to be expressed in most regions and cell types in the adult central nervous system, playing diverse roles. The Eph/ephrin complex mediates neurogenesis and angiogenesis, promotes glial scar formation, regulates endocrine levels, inhibits myelin formation and aggravates inflammation and nerve pain caused by injury. The interaction between Eph and ephrin is also considered to be the key to angiogenesis. This review focuses on the roles of Eph/ephrin bidirectional signaling in the repair of central nervous system injuries.

Bidirectional Connections between Depression and Ataxia Severity in Spinocerebellar Ataxia Type 3 Patients.

BACKGROUND: Spinocerebellar ataxia type 3 (SCA3), which is the most common subtype of SCA worldwide, exhibits common neuropsychological symptoms such as depression. However, the contribution of depression to the severity of SCA3 has not yet been thoroughly investigated. METHODS: The present study investigated the prevalence of depression using Beck depression inventory in 104 molecularly confirmed SCA3 patients from China. The putative risk factors for depression and whether the depression could affect the severity of ataxia were established by multivariable linear regression models. RESULTS: The frequency of depression in the study subjects was 57.69% (60/104), which was higher than that in SCA3 patients from a subset of other populations. The gender (p = 0.03) and severity (p < 0.01) of ataxia were those risk factors that could affect depression. Conversely, depression (p < 0.01) together with the duration (p < 0.01) of SCA3 could also play a positive role in the severity of ataxia. CONCLUSIONS: The extremely common depression results from motor disability caused by ataxia; it also affects the disease severity of SCA3. These findings suggested that depression was a part of neurodegeneration in SCA3 and necessitated intensive focus and interventions while caring for SCA3 patients.

Homozygote of spinocerebellar Ataxia type 3 correlating with severe phenotype based on analyses of clinical features.

BACKGROUND: Spinocerebellar ataxia type 3 (SCA3) is the most common subtype of SCAs worldwide. SCA3 homozygote is defined as expanded CAG repeats in both alleles that might exhibit severe phenotype due to gene dosage effect. However, a study on the systematic comparison of clinical phenotypes between homozygotes and heterozygotes to indicate these verity of phenotypes of homozygotes is still lacking. METHODS: A total of 14 SCA3 homozygotes (3 Chinese participants and 11 participants from various ethnicity in different published studies) and 143 Chinese heterozygotes of SCA3 were recruited for this study. The 95% confidence intervals (CIs) of age at onset and disease severity expected from heterozygous patients were analyzed to detect the phenotypic differences between homozygotes and heterozygotes. RESULTS: Almost all the homozygotes (13 of 14) were found to present a significant earlier age at onset compared with heterozygotes, because age at onset of most homozygotes was lower than the 95% CIs of age at onset of heterozygotes. Also, the clinical severity in most of the homozygotes (3 of 4) with identified clinical phenotypes was higher than the 95% CIs of severity in heterozygotes, indicating more severe clinical phenotypes in SCA3 homozygotes. CONCLUSIONS: The homozygosity for SCA3 could lead to an earlier age of onset and putative severe clinical features. The findings of the present study suggested an influence of gene dosage on SCA3 phenotypes.

Association Between Body Mass Index and Disease Severity in Chinese Spinocerebellar Ataxia Type 3 Patients.

Spinocerebellar ataxia type 3 (SCA3), the most common subtype of SCA worldwide, is caused by mutation of CAG repeats expansion in ATXN3. Body mass index (BMI) is an important modulatory factor in the progression of neurodegenerative disorders such as Huntington disease and amyotrophic lateral sclerosis. However, its relevance in SCA3 is not well understood. In this study, BMI was investigated in 134 molecularly confirmed SCA3 patients and 136 healthy controls from China. The multivariable linear regression models were performed to establish the putative risk factors for BMI, and whether BMI could affect the severity of ataxia. We found that BMI was significantly lower in the case group than that in the control group. The age at onset (positive correlation) and severity of ataxia (negative correlation) were the risk factors affecting BMI. Conversely, BMI along with the disease duration, the age at onset, and the numbers of CAG repeats could also have influence on the severity of ataxia. In conclusion, SCA3 patients had lower BMI than matched controls and BMI is a predictor of disease progression in SCA3. Nutritional intervention to promote weight gain could be a promising strategy to impede SCA3 progression.

Roles of Eph/ephrin bidirectional signaling in central nervous system injury and recovery.

Multiple cellular components are involved in the complex pathological process following central nervous system (CNS) injury, including neurons, glial cells and endothelial cells. Previous studies and neurotherapeutic clinical trials have assessed the molecular mechanisms that underlie neuronal cell death following CNS injury. However, this approach has largely failed to reduce CNS damage or improve the functional recovery of patients. Erythropoietin-producing human hepatocellular (Eph) receptors and ephrin ligands have attracted considerable attention since their discovery, due to their extensive distribution and unique bidirectional signaling between astrocytes and neurons. Previous studies have investigated the roles of Eph/ephrin bidirectional signaling in the developing central nervous system. It was determined that Eph/ephrin bidirectional signaling is expressed in various CNS regions and cell types, and that it serves diverse roles in the adult CNS. In the present review, the roles of Eph/ephrin bidirectional signaling in CNS injuries are assessed.

Voice Therapy Effect on Mutational Falsetto Patients: A Vocal Aerodynamic Study.

OBJECTIVE: The study aims to evaluate the effectiveness of voice therapy (VT) and analyze the vocal aerodynamic characteristics in mutational falsetto (MF) patients. METHODS: From October 2010 through May 2014, 26 patients with MF at Sun Yat-sen Memorial Hospital were studied retrospectively. Vocal assessment, including the 10-item Voice Handicap Index (VHI-10), fundamental frequency (F0), and vocal aerodynamic parameters (subglottic pressure [SGP]), aerodynamic power [AP], mean expiratory airflow, and maximum phonation time [MPT]), was proceeded before and after VT. RESULTS: Before VT, the mean F0, AP, and SGP of MF patients were significantly higher than Control Group, whereas mean MPT was significantly shorter. After a 4-week VT, the mean F0, AP, and SGP were decreased, and the mean MPT was significantly increased compared with the measurements obtained before VT. After the 4-week VT, the VHI-10 scores in 21 patients reverted to normal Control Group's level (Effective Subgroup), whereas the VHI-10 scores in the other 5 patients remained higher than the normal Control Group (Ineffective Subgroup). Subgroup analysis showed the mean AP and SGP of the Ineffective Subgroup were similar to the Control Group, whereas the Effective Subgroup showed higher AP and SGP. After the 4-week VT, MPT in both the Effective Subgroup and Ineffective Subgroup increased significantly, but AP and SGP in the Ineffective Subgroup did not change significantly. CONCLUSION: VT is an effective treatment for MF patients with laryngeal hyperfunction. Most MF patients can return to normal voice in 4 weeks. Vocal aerodynamic examination can help in predicting the VT effect and deciding the treatment plan. MF patients without laryngeal hyperfunction may need longer VT period or other adjuvant treatment.

Downregulation of AATK mediates microRNA-558-induced resistance of A549 cells to radiotherapy.

The deregulation of microRNAs (miRNAs) is often implicated in the control of sensitivity to radiotherapy. The objective of the present study was to identify the association between miR­558 and apoptosis­associated tyrosine kinase (AATK), and their importance in regulating the development of resistance to radiotherapy. The current study demonstrated that AATK, a radiosensitization-associated gene, is a target of miR­558 in lung cancer cells, using in silico analysis and a luciferase reporter system. Furthermore, it was determined that transfection of 30 or 50 nM miR­558 mimics and AATK specific siRNA markedly suppressed the mRNA and protein expression of AATK. To determine whether miR­558 was required for lung cancer cell radioresistance, A549 cells were treated with different doses of ionizing radiation, from 0 to 10 Gy, following transfection with miR­558 mimics or AATK specific siRNA. It was determined that the administration of miR­558 mimics or AATK specific siRNA alone did not significantly alter the survival rate of the cells. By contrast, in the cells exposed to 4, 6 or 8 Gy, the administration of miR­558 mimics or AATK specific siRNA significantly promoted cell survival rate and overexpression of AATK reversed this effect. In conclusion, these data demonstrate that the miR­558/AATK cascade is important for the radiosensitization of lung cancer cells and may be a potential radiotherapy target.

Serum miR-152, miR-148a, miR-148b, and miR-21 as novel biomarkers in non-small cell lung cancer screening.

Lung cancer, predominantly by non-small cell lung cancer (NSCLC), is the leading cause of cancer-related deaths over the world. Late diagnosis is one of important reasons for high mortality rate in lung cancer. Current diagnostic approaches have disadvantages such as low accuracy, high cost, invasive procedure, etc. MicroRNAs were previously proposed as promising novel biomarkers in cancer screening. In this study, we evaluated the predictive power of four candidate miRNAs in NSCLC detection. Our study involved 152 NSCLC patients and 300 healthy controls. Blood samples were obtained from the total 452 subjects. After miRNA extraction from serum, the expression of miRNAs in cases and controls were quantified by qRT-PCR and normalized to the level of U6 small RNA. Statistical analyses were performed to compare miRNA levels between cases and controls. Stratified analyses were employed to compare miRNA levels in NSCLC patients with different clinical characteristics. Serum miR-148a, miR-148b, and miR-152 were significantly downregulated in NSCLC patients. However, overexpression of serum miR-21 was observed in NSCLC patients. The combination of four candidate miRNAs exhibited the highest predictive accuracy in NSCLC screening compared with individual miRNAs (AUC = 0.97). Low level of miRNA-148/152 members may associate with advanced stage, large tumor size, malignant cell differentiation, and metastasis. High expression of miR-21 was possibly correlated with large size tumor and advanced cancer stage. Our results showed the dysregulation of miR-148/152 family and miR-21 in NSCLC patients. Hence, the four candidate miRNAs have great potential to serve as promising novel biomarkers in NSCLC screening. Further large-scale studies are needed to validate our results.

A prospective multicenter clinical study of extralevator abdominoperineal resection for locally advanced low rectal cancer.

BACKGROUND: Recent studies have shown that extralevator abdominoperineal resection has the potential for reduced circumferential resection margin involvement, intraoperative bowl perforation, and local recurrence rates; however, it has been suggested that extended resection may be associated with increased morbidity because of the formation of a larger perineal defect. OBJECTIVE: This study was undertaken to demonstrate the feasibility and complications of extralevator abdominoperineal resection for locally advanced low rectal cancer in China. DESIGN: This was a prospective cohort study. SETTING: The study was conducted at 7 university hospitals throughout China. PATIENTS: A total of 102 patients underwent this procedure for primary locally advanced low rectal cancer between August 2008 and October 2011. MAIN OUTCOME MEASURES: The main outcome measures comprised circumferential resection margin involvement, intraoperative perforation, postoperative complications, and local recurrence. RESULTS: The most common complications included sexual dysfunction (40.5%), perineal complications (23.5%), urinary retention (18.6%), and chronic perineal pain (13.7%). Chronic perineal pain was associated with coccygectomy (p < 0.001), and the pain gradually eased over time. Reconstruction of the pelvic floor with biological mesh was associated with a lower rate of perineal dehiscence (p = 0.006) and overall perineal wound complications (p = 0.02) in comparison with primary closure. A positive circumferential margin was demonstrated in 6 (5.9%) patients, and intraoperative perforations occurred in 4 (3.9%) patients. All circumferential margin involvements and intraoperative perforations were located anteriorly. The local recurrence was 4.9% at a median follow-up of 44 months (range, 18-68 months). LIMITATIONS: This was a nonrandomized, uncontrolled study. CONCLUSIONS: Extralevator abdominoperineal resection performed in the prone position for low rectal cancer is a relatively safe approach with acceptable circumferential resection margin involvement, intraoperative perforations, and local recurrences. Reconstruction of the pelvic floor with biological mesh might lower the rate of perineal wound complications (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A161).

The vocal aerodynamic change in female patients with muscular tension dysphonia after voice training.

OBJECTIVE: To investigate the changes of vocal aerodynamics indicators after voice training in female patients with muscular tension dysphonia (MTD). METHODS: Twenty-one female MTD patients (before voice training and 12 weeks after voice training) and 20 female volunteers with normal voices (the control group) received vocal aerodynamic analysis. Parameters included subglottal pressure (SGP), aerodynamic power (AP), mean expiratory airflow (MEA), and maximum phonation time (MPT) were recorded and analyzed by phonatory aerodynamic system. RESULTS: Before voice training, the median SGP and mean AP were higher than control group, whereas median MPT was shorter, and these differences were statistically significant. After 12 weeks of voice training, the median SGP and mean AP were decreased and the median MPT was increased compared with the measurements obtained before training, and these differences were statistically significant. The differences of median SGP, mean AP, mean MEA, and median MPT between MTD after 12 weeks of training and control group were not statistically significant. CONCLUSION: Voice training is an effective treatment for MTD patients. Aerodynamic analysis can effectively evaluate the vocal functional status of MTD patients before and after training, which is beneficial for the treatment efficacy evaluation.

Correlation among the dysphonia severity index (DSI), the RBH voice perceptual evaluation, and minimum glottal area in female patients with vocal fold nodules.

OBJECTIVES: To investigate the clinical significance and correlation of the dysphonia severity index (DSI), the RBH (roughness [R]; breathiness [B]; hoarseness [H]) perceptual voice quality evaluation, and minimum glottal area (MGA) in patients with vocal fold nodules and validate the practicality of the DSI further. METHODS: The DSI evaluation, the voice RBH perceptual evaluation, and the MGA were performed on 30 female patients with vocal fold nodules (the patient group) and 30 female volunteers with normal voices (the control group). The DSI determination was calculated using the following formula: DSI = 0.13 × MPT + 0.0053 × F(0)-High - 0.26 × I-Low - 1.18 × Jitter(%) + 12.4. The RBH evaluation was graded according to four scales. The MGA was measured by KayPENTAX Kips (7105) software. The differences among the DSI, the RBH grade, and MGA of the patients were compared. RESULTS: The median DSI values of the patient group and the control group were -0.81 and 3.79, respectively, and the difference was statistically significant (P < 0.01). The median MGA of the patient group and the control group were 355.5 and 121, respectively, and the difference was statistically significant (P < 0.01). DSI exhibited moderate negative correlation with R (rP = -0.686, P < 0.01), B (rP = -0.609, P < 0.01), and H (rP = -0.487, P < 0.01). MGA demonstrated moderate positive correlation with R (rP = 0.667, P < 0.01), B (rP = 0.545, P < 0.01), and H (rP = 0.449, P < 0.01), whereas MGA showed strong negative correlation with DSI (rP = -0.888, P < 0.01). CONCLUSIONS: The application of the DSI as an objective parameter to evaluate dysphonia in female patients with vocal nodules has significant clinical application and good correlation with MGA measurement.

[Analysis of the clinical manifestations and electrophysiological changes in 32 patients with atypical myasthenia gravis].

OBJECTIVE: To study the clinical characteristics and electrophysiological changes in patients with atypical myasthenia gravis (MG). METHODS: The characteristics of the clinical symptoms and electrophysiological changes were investigated in 32 patients with atypical MG diagnosed in our hospital from January 2004 to December 2008. RESULTS: The ages of the patients ranged from 7 to 70 years. Five patients were diagnosed to have ocular MG (OMG), among whom 2 patient only complained of eye discomfort and blurred vision. Twenty-seven patients had generalized MG, and 6 of them showed muscle weakness of the limbs with or without mild difficulty in swallowing or respiratory muscles, but free of muscle dysfunctions in muscles of eyes, head, neck or face. Another 2 patients manifested muscular atrophy. Twenty-three patients (71.9%) displayed both fluctuating symptoms and positive results of fatigue test. Twenty-nine patients (90.6%) have positive results in the neostigmine test. Two patients in the OMG group (40.0%) showed positive results in the low frequency repetitive nerve stimulation (LFRNS), as compared with the 21 patients in the generalized MG group (71.9%) showing positive results. The total positivity rate of LFRNS was 71.9% in the total patients, consistent with the published data. CONCLUSIONS: In MG patients with atypical clinical symptoms, negative results of neostigmine test and fatigue test, LFRNS test can be an indispensable method to increase detection rate of MG and reduce erroneous or missed diagnosis.