Objective To investigate immunological mechanism underlying leflunomide ( LEF ) against experimental allergic encephalomyelitis ( EAE) by studying the effects of LEF on peripheral blood CD28/CTLA-4 costimulatory molecules expression in guinea pig with EAE.Methods 50 adult female guinea pigs were randomly divided into normal control group,low dose group,EAE control group,middle dose group,and high dose group, 10 guinea pigs in each group respectively.Low, medium and high dose group were treated with LEF 10 mg/kg· D, 20 mg/kg· D and 40 mg/kg· D orally, 1 times/day, to the termination of the experiment.The expression of CD28, CTLA-4 were detected by flow cytometry, incidence was recorded at the same time.Results Compared with EAE control group,high dose and middle dose group incubation period were prolonged, progress period were shorten and neurological dysfunction score decreased(P<0.05).Compared with normal control group, the expression of CD28 of EAE control group increased and the decreased expression of CTLA-4 (P<0.05).High, middle dose treatment group compared with EAE control group CD28 down regulated expression (P<0.05), but the expression of CTLA-4 increased(P<0.05).Among the treatment groups, of CD28 molecules with high dose group decreased significantly(P<0.05), the expression of CTLA-4 molecules with high dose treatment groups upregulated significantly (P<0.05).Correlation analysis showed that the EAE control group, the treatment group the CD28/CTLA-4 ratio in peripheral blood and nerve dysfunction score is proportional ( r=0.85, P=0.002; r=0.77, P=0.000).Conclusion LEF can reduce EAE guinea pig neurological symptoms, the better and the higher dose effect.Its mechanism may be through down-regulation of CD28 molecules in peripheral blood, upregulation of the expression of CTLA-4 molecule.so as to reduce the inflammatory response, relieve the clinical symptoms.

Objective To investigate the etiological, clinical and neuroimaging features of symmetric corpus callosum lesions. Methods The clinical data of 27 patients with symmetric corpus callosum lesions were analyzed including the etiological, clinical and neuroimaging data retrospectively. Results In 27 patients, 16 patients suffered from chronic alcoholic encephalopathy, 5 patients suffered from viral encephalitis, 2 patients suffered from disturbance of water and electrolyte, 1 patient suffered from acute disseminated encephalomyelitis(ADEM), 2 patients suffered from brain trauma, and the etiology of 1 patient was unknown. Clinical manifestation: 8 patients had conscious disturbance, 5 patients had psychological and behavior disorder, 5 patients had epileptic seizure, 4 patients had ataxia, 3 patients had dysarthria and 2 patients had headache. There were abnormalities in CT scans and MRI. Manifestations in CT scans were symmetric low-density focus with clear boundary in corpus callosum. The performance in MRI was low-signals on T1WI but high signals on T2WI and DWI images, and there might be other intracranial lesions. In the follow-up period, foci disappeared in 15 patients, and foci persisted in 7 patients. Four patients lost in follow-up periods, and 1 patient was not followed up because of death. Conclusions The causes of symmetric corpus callosum lesions include chronic alcoholic encephalopathy, infections, disturbance of water and electrolyte and demyelination. And in some patients the cause is unknown up to now. The etiological treatment and symptomatic treatment are the common treating ways in clinic.

Objective To investigate the etiology and risk factors of stroke in young adults from Southern Sichuan, China to provide a basis for prevention and treatment of stroke. Methods The data of 398 young patients with first-ever stroke (aged 18 to 44) admitted to department of Neurology, the Affiliated Hospital of Luzhou Medical College from 2009 to 2013 was retrospectively analyzed. Four hundred twenty-five cases of stroke (aged greater than or equal to 45) were re?cruited by stratified random sampling to analyze its causes and risk factors in the same period. Results ① Young stroke accounted for 6.09% of all hospitalized stroke patients in which 78.39% of young stroke was ischemic, 64.57%was male and 58.04% aged from 40 to 44. ② According to TOAST etiology classification group, the percentage of large-artery atherosclerosis, small-vessel, cardioembolism, other determined and undetermined reasons were 56.09%, 17.95%, 9.93%, 10.90% and 5.13% in young stroke, respectively. Compared with the elderly group, other determined and undetermined reasons were higher, and the small-vessel was lower in young stroke (P<0.05). Hypertensive cerebral hemorrhage accounted for 50%of Hemorrhage in young group, and the type of Hemorrhage between two groups was no statistically significant.(P>0.05).③ Risk factors analysis revealed that the constituent ratio of smoking (34.92%), hyper?lipidemia (31.41%), alcohol (20.10%), obesity (13.07%), rheumatic heart disease (6.03%) in youth group were higher whereas hypertension(66.12%), diabetes(20.47%)and coronary heart disease(10.82%)were lower in young stroke com?pared with the elderly group (P<0.05). Conclusion ①Large-artery atherosclerosis is the most common etiology of youth ischemic stroke. ② Hypertensive cerebral hemorrhage is the most frequent type in Hemorrhagic stroke. ③ Hyperten?sion, smoking and hyperlipidemia are the most common risk factors to stroke.