Objective To examine the values of Regional Homogeneity (ReHo) in first-episode, treatment-naive patients with major depressive disorder before and after antidepressant treatment in order to explore the neural mechanism of antidepressants. Methods Twenty-five first-episode, treatment-naive patients with major depressive disorder, which met with DSM-IV diagnosis criteria underwent fMRI resting-state scans before and after 8-week antidepressant treat-ment. Paired Samples T-test was used to analysis the differences between two groups. Results The ReHo in the patient group after treatment were significantly decreased in the right medial frontal gyrus, left inferior parietal lobule, left middle temporal gyrus, left insula, right precuneus, left cingulate gyrus and posterior lobe of the cerebellum , while significantly in-creased in the right medial frontal gyrus, left medial frontal gyrus, right inferior parietal lobule, left postcentral gyrus and right middle temporal gyrus compared with before treatment. Conclusions E xtensive abnormal activity within the default mode network in the resting-state may be involved in the neuropathophylogical substrate of depression and the abnormal activity can be partly reversed by antidepressant treatment, suggesting that regional homogeneity can be used to dynamical-ly evaluate the effect of antidepressant treatment.

Objective To explore the role of white matter injuries in the schizophrenia induced by the NMDA re-ceptor antagonist. Methods Adult male C57BL/6J mice (8 week old) were equally divided into four groups. One group was sub-chronically treated with saline solution, and the other three groups were intraperitoneally treated with MK-801 at dose of 0.025 mg/mL (M1), 0.050 mg/mL (M2) and 0.100 mg/mL (M3) in a volume 10 ml per kilogram body weight. All ani-mals were tested using Morris water maze at the 9th-15th day and using the Hole Board exploration as well as Rota Rod performance tests on the 16th day. The myelin basic protein (MBP) and the ultrastructure of the myelin sheaths in the cor-pus callosum were then examined using immunohistochemical methods, transmission electron microscope technique and stereological methods. Results The repeated sub-chronic MK-801 treatment did not induce impairment of spatial learning and memory in Morris water maze. The MK-801 treatment at 0.25 mg/kg and 1.00 mg/kg but not at 0.50 mg/kg resulted in less exploration to a new environment. The myelin staining with anti-MBP antibody was less intense in all three schizo-phrenic groups when compared to saline control group (P<0.01). Furthermore, MK-801 treatment caused pathological al-terations of the myelin sheaths including segmental demyelination of myelinated fibers and splitting of myelin sheath lamel- lae in schizophrenic groups. The ratio of the injured myelinated nerve fibers in the corpus callosum of MK-801 treated mice [M3 group, (22.42 ± 4.24)%] was significantly higher when compared to the control mice [(3.84 ± 1.35)%,P<0.01)]. Conclusions The present study demonstrated the white matter damages, mainly low MBP expression and segmental demye-lization in the corpus callosum in the mice sub-chronic treated with MK-801, indicating that the white matter changes might be involved in the schizophrenia induced by NMDA antagonist.

Objective To explore the characteristics of selective attention function in patients with silent cerebral in-farction (SCI) and depression, the relationship between depression, selective attention and cognitive dysfunction. Methods Eighty-two patients with SCI and 82 normal subjects were selected and evaluated by using Hamilton Depression Rating Scale (HAMD), Montreal cognitive assessment (MoCA) and Stroop color-word test (CWT). Patients with SCI were further classified into depression subgroup and no-depression subgroup based on the score of HAMD. Results The score of MoCA was lower in SCI group (23.11 ± 5.41) and was much lower in depression subgroup (20.31 ± 5.44) compared with control group (28.70 ± 2.18) (all P<0.01). Compared with control group, the reaction times of card A, B, C and Stroop interference effects (SIE) were prolonged in SCI group. The reaction time of card A, B, C and SIE were (33.25±14.10);(42.45±15.18);(104.68 ± 25.08) and (62.24 ± 21.53) in depression subgroup, respectively. The error counts of card B, C and SIE were in-creased (P<0.05) in SCI group. The error counts of card B,C and SIE were (3.59±2.14), (15.67±7.20) and (12.08±6.46) in depression subgroup, respectively. The scores of MoCA were negatively correlated with the reaction time and error counts of SIE (r=-0.429,r=-0.500,all P<0.01).The location of infarction was correlated with the score of HAMD and error counts of SIE to some degree: both of the scores were higher in patients with left infarction compared with right infarction and were higher in patients with cortex infarction compared with subcortex infarction. Conclusion The present study revealed that patients with SCI and depression have selective attention deficit which is closely correlated with the level of cognitive function.

Objective To explore the relationship between collateral circulation and clinical manifestation after se-vere stenosis or occlusion of internal carotid artery. Methods According to the clinical manifestation, 78 cases of ICA ste-nosis or occlusion confirmed by digital subtraction angiography (DSA) were divided into two groups:asymptomatic group (n=31) and symptomatic group (n=47). Collateral circulation pathway in circle of Willis and the mean flow velocity of the middle cerebral arteries (MVMCA) were measured by Transcranial Doppler Ultrasonography (TCD). The correlation of the types of intracranial collateral circulation and clinical manifestation was analyzed. Results ① The collateral circulation opening rate of severe stenosis or occlusion of internal carotid artery in 78 cases of patients was 70.5%(55/78). The collat-eral patency rate (27/31, 87.1% of patients) was higher in asymptomatic group than in the symptomatic group (28/47, 59.6%of patients)(P<0.01).②Collateral patency of anterior communicating artery (ACoA)in asymptomatic group (24/31, 77.4%of patients) was higher than that in symptomatic group (20/47, 42.6%of patients) (P<0.01). Collateral patency of ophthalmic artery (OA) in symptomatic group (21/47, 44.7%of patients) was higher than that in asymptomatic group(6/31, 19.4%of patients)(P<0.05). The opening rate of ACoA was significantly higher than that of either the posterior commu-nicating artery (PCoA) or OA collateral circulation in asymptomatic group (P<0.05).③The mean flow velocity of the af- fected side middle cerebral arteries (MVMCA) in asymptomatic group (51.58±12.36cm/s) was significantly higher than that in symptomatic group (32.23±10.31cm/s) (P<0.01). Conclusion The clinical manifestation is closely related to arterial circle of Willis collateral circulation opening after severe stenosis or occlusion of internal carotid artery and collateral patency of anterior communicating artery is the major collateral supply vessel.

Objective To investigate the difference of spatial working memory among first-episode patients with deficit and nondeficit schizophrenia. Methods The study recruited 116 first-episode treatment-naive patients with schizo-phrenia, and 60 normal controls. Positive and Negative Syndrome Scale (PANSS) was used to assess symptoms of patients and Schedule for the Deficit Syndrome (SDS) was used to divide schizophrenia patients into deficit group (28 patients) and nondeficit group (88 patients). Spatial Working Memory (SWM) test from the Cambridge Neuropsychological Test Automat-ed Battery (CANTAB) was used to test the spatial working memory function. Results Adjusted for age, gender and years of education, there were significant differences in the performance of between errors of 4 boxes (P=0.03), between errors of 6 boxes (P=0.01), between errors of 8 boxes (P=0.03), total errors (P=0.01) and strategy (P<0.01) between deficit and nondef-icit patients, and both groups were poorer than the control group. The SWM of deficit and nondeficit patients has no corre-lation with the negative symptoms (P>0.05). Conclusion The impairment of SWM was more severe in deficit schizophrenia patients than in nondeficit patients at early stage of the disease, suggesting they are different subtypes of schizophrenia.

Objective To explore the feature of functional connectivity of default mode network (DMN) and salience network (SN) in unmedicated schizophrenia patients during a resting state by functional magnetic resonance imaging (fM-RI). Methods The SPM8 and DPARSFA softwares combined with independent component analysis (ICA) were used to in-vestigate functional connectivity (FC) of the DMN and SN in 27 unmedicated patients with schizophrenia and 27 age-and gender-matched healthy controls. Results Concerning the DMN, patients with schizophrenia showed decreased FC in right inferior frontal gyrus , right precuneus(unadjusted P<0.05)and increased FC in right middle cingulate gyrus, left middle frontal gyrus(unadjusted P<0.05). With regard to the SN, patients showed reduced connectivity in left inferior frontal gyrus, right inferior frontal gyrus, left anterior cingulate, left postcentral gyrus(unadjusted P<0.05)and increased connectivity in left superior temporal gyrus(unadjusted P<0.05). Correlation analyses showed that the increased FC of left superior temporal gyrus significantly correlated with PANSS-positive symptoms(r=0.568,P=0.002)and decreased FC of right precuneus significantly negatively correlated with delusion symptom(r=-0.458,P=0.016). Conclusion This study provides evidence for resting state functional abnormalities of DMN and SN in unmedicated schizophrenia patients. These aberrant function connectivities in some brain regions of the two networks could be a source of abnormal introspectively-oriented mental actives.

Objective To explore the influence of genetic and environmental factors on emotional and behavioral problems in children and adolescents using twins quantitative method. Methods One hundred fifty-six twins pairs, aged from 6 to 18, were included in the present study. The parental version of the strengths and difficulties questionnaire (SDQ)was used to evaluate their emotional and behavioral problems. The DNA test of twin zygosity was conducted using DNA extracted from buccal mucosa or venous blood samples. The influence of genetic and environmental factors on emo-tional and behavioral problems was analyzed using structural equation modeling(SEM). Results Shared environment and special environment had impact on emotional symptoms and their contribution to the total variance of emotional symp- tom was 0.42 and 0.58, respectively. Prosocial behavior was mainly affected by shared environment and the contribution of shared environment to the total variance of prosocial behavior was 0.89. Genetic factors had greater influence on hyperac-tivity/attention deficit and the contribution of genetic factors to the total variance was 0.62. Shared environment had more influence on conduct disorder and the contribution of shared environment to total variance was 0.56. Heredity, shared envi-ronment and special environment had impact on peer problems and their contribution to the total variance was 0.24, 0.33 and 0.43, respectively. Conclusion In child and adolescent period, emotional symptoms are only affected by environ-ment, while behavior problems are affected by the combination of heredity and environment. Different behavior problems are affected by different genetic and environmental factors.

Objective To investigate the effects of repeated neonatal administration of dizocipline maleate (MK-801), the N-methyl-D-aspartate (NMDA) receptor antagonist, on the expression of NMDA receptor subunits NMDAR 1 (NR1), NMDAR2A (NR2A), NMDAR2B (NR2B) and the protein levels of nerve growth factor (NGF) in neonatal rats. Methods Neonatal Sprague-Dawley (SD) rats were randomly divided into research group and control group, with 15 ani-mals in each group. Rats were administrated subcutaneously with MK-801 or normal saline from postnatal day (PND) 5 to PND14 (0.25 mg/kg, twice a day). The expression levels of NR1, NR2A, NR2B and NGF were examined on PND15, PND42 and PND70 in the prefrontal cortex and hippocampus. Results At PND15 (neonatal period), there were no signifi-cant differences in the expression levels of NR1, NR2A, NR2B and NGF in the prefrontal cortex and hippocampus be- tween the two groups (P>0.05). At PND42 (adolescence), NGF protein levels in the prefrontal cortex was significantly low-er in research group than in control group [(56.19±37.87) vs. (152.54±53.92), P<0.01]. At PND70 (adulthood), the expres-sion of NR1, NR2A in the hippocampus was significantly higher in research group than in control group [NR1:(149.55%± 27.00%) vs. (100.00%±32.08%);NR2A:(171.54%±19.85%) vs. (100.00%±51.04%). P<0.05]. Conclusion Neonatal re-peated treatment of MK-801 increases the expression of NMDA receptor subunits NR1, NR2A in the hippocampus in adulthood while decreases the expression of NGF in the prefrontal cortex in adolescence, suggesting that neonatal block-ade of the NMDA receptor may influence the growth and development of the nervous system.

Objective To evaluate whether ABCD2 score can discriminate dizziness patients with and without stroke. Methods This retrospective case-control observational study was conducted in 403 hospitalized patients. According to the final discharge diagnosis, the patients were divided into two groups:the stroke group and non-stroke group. The areas un-der the receiver-operator curves and 95%confidence intervals were then generated to estimate the diagnostic value. Re-sults ABCD2 score was higher in stroke group than in non-stroke group. Conclusions ABCD2 score can be used to quickly identify dizziness patients with cerebrovascular diseases.

Objective To investigate the current status of secondary prevention of cerebral infarction in Longquanyi District of Chengdu. Methods Prospective Investigation on the secondary prevention was conducted in 94 pa-tients with cerebral infarction at 3, 12 and 24 months following stroke. Results The percentages of patients receiving anti-platelet therapy, antihypertensive treatment, antidiabetic drug treatment and statin therapy were 96.8%, 92.1%, 91.7%and 63.8%at hospital discharge, 79.8%, 88.9%, 91.7%and 55.3%at 3 months, 76.1%, 75.0%and 41.4%, 63.8%at 12 months and 33.0%, 71.4%;58.3%and 22.3%at 24 months, respectively. None of stroke patients with atrial fibrillation re-ceived anticoagulation therapy. Conclusion There is a large gap between the current practice of secondary prevention and guideline in patients with cerebral infarction in Longquanyi District of Chengdu.