Objective To study the changes of learning-memory ability and synapse of hippocampus after radiation injuries. Methods Sprague-Dawley rats were grouped according to radiation dose to 20Gy group,30Gy group radiated by linear accelerator and control group were used before radiation and 120 days after radiation. Morris maze test were taken to study the learning and memory ability of rats in each group. Average escape latency and search strategy were scaled and analyzed in each group. The parameters of synapse in CA3 area of hippocampus were studied by using electron microscope and image analyzer. Results AEL of 20Gy group was (41. 17 ±10.76 ) s and score of SS was 27.13 ± 2.34 after 120 days' radiation but AEL of 30 Gy group was (78.49 ± 9.32)s and the score of SS was (23.19 ± 7.65 ) nm. There were significant statistic differences Compared with control group and before radiation (P ＜ 0.05 ). The thickness of PSD of 20 Gy group was ( 22.03 ± 6.84 ) nm after 120days' radiation and (23.19 ± 7.65 )nm in 30 Gy group. There were significant statistic differences compared with control group and before radiation. It was observed that both in 20 Gy and 30 Gy group' s the length of synaptic activity area was shorter,the curvature of synaptic interface was smaller,the width of synaptic cleft and the thickness of PSD was narrower than that of control group. Conclusion There was close relation between the changes of learning-memory ability and synapse of hippocampus after radiation injuries.

Objective To discuss the relationship between carotid atherosclerosis and the ischemic cerebrovascular disease(ICVD).Methods 1583 subjects with acute ICVD enrolled from June 2001 to December 2004 underwent carotid artery duplex ultrasonography.Logistic regression was performed to analyze the relationship between carotid atherosclerosis and ICVD.Results 86.5%(1369/1583)of all the patients had a varying degree of carotid atherosclerosis,in which the occurrence of the atherosclerotic plaques(1286/1583,81.2%)higher than that of stenosis of the extracranial carotid(214/1583,13.5%).There was a significant difference in the incidence of carotid atherosclerosis between patients from the TIA group(198/317,62.5%)and from the cerebral infarction group(1087/1266,85.9%).Carotid atherosclerotic plaques were most commonly seen in the bifurcations of the common carotid artery(665/1286,51.7%).The severity of stenosis of the extracranial carotid and the formation of the atherosclerotic plaques were significantly correlated to the risk factors of cerebrovascular disease.Conclusions Atherosclerotic plaques are dominant characteristics of carotid atherosclerosis in the patients with ICVD in Foshan.There is a positive correlation between carotid atherosclerosis and ICVD.

BACKGROUND:Severe acute respiratory syndrome (SARS),an acute infection with a mutant coronavirus,is characterized by acute pulmonary inflammatory injury accompanied by possible multiple organ injuries. Besides somatic symptoms,affective disorder constitutes an obvious neuropsychiatric symptom in SARS patients.OBJECTIVE:To analyze the clinical features of SARS with neuropsychiatric involvement.DESIGN:A retrospective case analysis.SETTING:Department of Neurology,Department of Respiratory Diseases and Department of Radiology of Affiliated Hospital of Sun Yat-sen University.PARTICIPANTS:Totally 325 SARS patients treated in the Second Affiliated Hospital of Sun Yat-sen University and the 8th People's Hospital of Guangzhou from February 2003 to May 2003 were involved,including 173cases who developed neuropsychiatric symptoms.METHODS:The clinical data of 325 of SARS including 173 cases with neuropsychiatric symptoms were retrospectively analyzed.MAIN OUTCOME MEASURES:Clinical neuropsychiatric symptoms,ophthalmoscopic examination,and pathological findings in autopsy.RESULTS: ①The incidence of neuropsychiatric involvement was about 53.2% in SARS patients. The manifestations consisted mostly of headache (67.1%),dizziness(28.9%),conscious-ness disturbance(10.4%),mental disorder(4.6%), local orientational disorder(0.6%),seizures(1.2%),and affective disorders (30.6%);anxiety occurred in 20.2%,depression in 6.4%,suicidal tendency in 1.2%,and phobia in 7.5% of the patients with neuropsychiatric involvement. ②Among the 325 patients,56 were in critical condition of whom 47 had accompanying neuropsychiatric impairment,with significantly greater incidence than that in mild cases (P＜0.01). ③Ophthalmoscopic examination performed in 4 patients showed blurred margin of the optic disc with retinal venous congestion. ④Autopsy in 2 cases identified edema of the perivascular tissue and vascular wall of the small veins with mononuclear cell and lymphocyte infiltration,neuron degeneration and demyelination in focal brain tissues.CONCLUSION:The manifestations of neuropsychiatric involement can vary in association with the severity of SARS,and the typical pathological changes include edema,neuronal demyelination etc.in the brain.

OBJECTIVE To study the characteristic of nosocomial pulmonary infection to find out the measures for prevention and control.METHODS The patients with radiation brain injuries(RIB) from Oct 2004 to Jun 2007 underwent retrospective investigation.The reasons and sites of pulmoary infection were analyzed.RESULTS The incidence of pulmonary infection of patients with RIB after radiotherapy was 68.5%.Major factors of infection were bulb palsy,invasive treatment and hormone usage.The Gram-negative bacteria were the predominant pathogens.CONCLUSIONS The nosocomial pulmonary infection is related to many factors.Antibiotic usage according to drug susceptibility results and controlling of the risk factors are important measures to reduce the rate of infection.

Objective To study the roles of AADC gene therapy for Parkinson’s disease and its action by coadministrating exogenous L dopa and discuss the effectiveness by way of cationic liposome mediated gene transferring into the brain Methods Injecting either the pCDNA3 AADC Liposome or pCDNA3 Liposome complexes into the striatum of Parkinsonian SD rats in experimental and control groups respectively, observing their improvements of rotational behavior, and furthermore, observing the improvement after combining with administration of exogenous L dopa were carried out The expression of AADC were assayed by using immunohistochemical staining Results (1) Intracerebral transplantation of pCDNA3 AADC Liposome complex improved the rotational behavior of Parkinsonian rats in some degree when its being observed at 3,7,14,21 and 28 days( P 0 05), the maximum improvement was at the time of 1 week (2) After coadministration of exogenous L dopa (10 mg/kg weight) per days, the experimental groups reached much more obvious improvement than that in the controls at the same time described above( P 0 05) (3) Immunohistochemical staining showed that the AADC were expressed stably in the striatum Conclusions Increase of AADC gene expression in the brain may improve the rotational behavior of Parkinsonian rats as well as elevate the curative effect of exogenous L dopa therapy, suggesting that it should be helpful to maintain a long term L dopa theraputic effect at a much lower level and avoid all kinds of side effects The technic of intracerebral gene transfer mediated by cationic liposome might be a new method for gene therapy of PD

BACKGROUND: Memory loss is the main presentation during the earlier stage of radiative eneephalopathy, and it was reported that ganglioside (GM1) played important role in neural rehabilitation, particular in the improvement of memory.OBJECTIVE: To study the improving effect of GM1 on spatial learning and memory retardation in rats following radiative encepholopathy. DESIGN: Randomized control and comparative observing study based on the experimental animals.SETTING: Department of Neurology and Department of Radiation of Second Affiliated Hospital of Sun Yat-sen University.MATERIALS: This study was carried out at the Laboratory of the Second Hospital Affiliated to Sun Yat-sen University between March 2001 and May 2002. Tctally 80 SD rats were randomly selected and divided into control group, GM1 treatment group, physiological saline group and non-intervention group with 20 rats in each group.INTERVENTIONS: Rats in GM1 group, physiological saline group and non-intervention group subjected to head 60Coγ irradiation of 7Gy each time after anesthesia, once a day for consecutive 6 days, and the total dosage was 42Gy while rats in control group did not receive irradiation after anesthesia. Rats in GM1 and physiological saline(PS) group were given intraperitoneal injection of GM1 and physiological saline of 30 mg/kg respectively at 1 hour after each time of radiation, once a day for consecutive 6 days but not in control group and non-intervention group. Evaluation: ①After irradiation, morris water labyrinth navigation test was used to assess the capability of learning and memory of rats by the time for reaching platform (latency); ② Spatial searching test was used to detect their spatial memory after learning how to reach the platform by recording the way of rats searching the platform in 120 s and calculating the percentage of swimming distance in platform quadrant in the total distance; ③ After labyrinth test, brains were taken out of the rats in GM1 group, PS group and non-intervention group for observing the histological and pathological changes in rat brains.RESULTS: ① The latency become stable form onset of the 4th day in each group. On the 5th day, the searching platform latency in GM1 group was(13.6±1.4) s, shorter than(17.1±2.9) s of PS group and [(15.8±2.2) s, (P＜0.05)] of non-intervention group; ② Rats in GM 1 and control group were found capable of searching platform according to their spatial memory, presented by swimming trail most located in platform quadrant while rats in PS and non-intervention groups were found mostly swimming around the pool with moving trails distributed randomly. The percentage of swimming distance in platform quadrant was found higher in GM 1 treatment group than in the PS group and non-intervention group, but lower than that in the control group; ③ Histological examination revealed slight neuronal degeneration in PS group, part of which was changes of vacuolar degeneration with cell shrank, chromosome concentrated and nuclei gathered aside, and the number of astrocytes also decreased; the pathological changes in non-intervention group and PS group were similar; in GM1 group, part neurons became smaller with peripalsm turning red but the pathological changes, such as the number of cells,neuclei shrank and gathered aside, and vacuolar changes were less than those of the former two groups.ONCLUSION: Radiative encephalopathy would result in obvious learning nd memory impairments in rats but histological and pathological changes due o brain radiation injury can be attenuated with the treatment of GM1, implying that GM1 may play important role in the improvement of radiation-induced spatial learning and memory loss.

BACKGROUND: At present, the researches on murine model of acute radiation encephalopathy are still in investigation, and mature model making method is not clear.OBJECTIVE: To establish a murine model of acute radiation encephalopathy in order to provide a good foundation for further researches of radiation encephalopathy(REP) mechanism and therapy.DESIGN: Randomized controlled study based on the experimental animals.SETTING: Animal laboratory in a university hospital. The Second Affiliated Hospital of Sun Yat-sen University.MATERIALS: The experiment was completed in the Laboratory of the Second Affiliated Hospital of Sun Yat-sen University from June 2001 to August 2002. Totally 30 female and 30 male SD rats, weighted(300 ± 30) g, were selected from the Animal Experiment Center of Sun Yat-sen University, and randomly divided into blank control group with 20 rats and experimental group with 40 rats.METHODS: Fourty rats' brain received 60Co γ-ray irradiation with the dosage of 7 Gy/time per day for 6 consecutive days with the total dosage of 42 Gy. The amount of ingestion and drinking, general activities, central nervous system(CNS) symptoms and signs were recorded every day. The hairs and skin of irradiated field and weight were checked and recorded weekly. On the 3rd, 7th, 14th, 30th days after radiation, the brain tissue was collected and the histopathologic changes were examined.Histopathologic changes after radiation.RESULTS: Since the third day, the ingestion and drinking amount of irradiated rats were decreased. The general activities were increased for the first two days, but decreased without abnormal nervous signs on the 3rd day. The rats in experimental group had a slower weight gain than those of control group, and the difference between them was of no statistical significance. All rats had slight alopecia and neuronal necrosis 2 weeks after irradiation.CONCLUSION: The irradiation method is reliable, practical and good for modeling REP process, which can be used in preventing or reducing the harm effect of radiation therapy on brain tissue.

[ ABSTRACT] AIM:To investigate the effects of sinapic acid ( SA) on the proliferation and apoptosis of rat vas-cular smooth muscle cells (VSMCs) induced by high glucose (HG).METHODS:Cultured A7r5 cells were randomly di-vided and treated as indicated.The cell viability was determined by MTT assay.DNA synthesis was measured by BrdU as-say.Cell cycle progression and cell apoptotic rate were determined by flow cytometry analysis.The levels of reactive oxygen species (ROS) were detected by ELISA.The protein levels of cyclin D1, P21, P27, phosphorylated protein kinase C (p-PKC), p-P38 andβ-actin were evaluated by Western blot.RESULTS:Compared with control group, the viability of A7r5 cells was significantly enhanced, the DNA synthesis was increased, the cell cycle progression was promoted, the levels of ROS were elevated, the cell apoptotic rate was reduced, the protein expression of P21 and P27 was decreased, and the pro-tein levels of cyclin D1, p-PKC and p-P38 were increased in HG group (all P<0.05).These effects were reversed by SA (0.1, 1 and 10 μmol/L) treatment in a dose-dependent manner (all P<0.05).Both P38 inhibitor SB203580 and PKC inhibitor chelerythrine significantly inhibit HG-induced PKC/P38 activation and cell viability ( P <0.05).CONCLU-SION:SA inhibits HG-induced VSMCs proliferation and promotes cell apoptosis via reducing PKC/P38 activation.