BACKGROUND: It is well known that central noradrenergic system takes part in learning and memory, but there are a few researches focused on the effects of impairing the central noradrenergic system on rat' s P3-like cognitive potential.OBJECTIVE: To study the effects of impairing the central noradrenergic system on rat's P3-like cognitive potential.DESIGN: Randomized controlled study based on the experimental animals.SETTING: Department of physiology in a medical college of a university.MATERIALS: Totally 30 male SD rats, clean degree, weighing from 500 to 600 g, were selected from the Experimental Animal Center of Sun Yat-sen Medical University(certificate: 26-99A018), drank freely and fed timely under the normal condition. After Y-maze test of all the rats, 24 rats with normal learning and memory function, which met the criteria specified in the description of Y-maze test, were randomly divided into three groups(8 rats in each group): control group, 6-oxidopamine (6-OHDA) injection group and saline control group.INTERVENTIONS: The models of central norndrenergic system impairment were made by injecting 6-hydroxysopamine(6-OHDA) into the bilateral dorsal noradrenergic bundle in dentate granule(DG). Then Y-type maze test and elicitation of P3-likewere carried out respectively before and after the models were built.MAIN OUTCOME MEASURES: Main outcome: P3-like latency, total reaction time(TRT) and error number(EN). Secondary outcome: Results of P3-like test recorded in the 12 days after the models were built.RESULTS: As compared with the controls, the model rats' P3-like latency and total reaction time(TRT) prolonged and error number(EN) increased statistically ( P ＜ 0.05 ).CONCLUSION: Central NE takes part in the activities of learning and memory and plays a certain role in the production and integration of P3 -like.

AIM: To separate and identify the mesenchymal stem cells (MSCs) from human fetal bone and to study their differentiation to hepatocyte like cells under the action of chemical induction.METHODS: The MSCs from human fetal bone were isolated and purified according to the different growth characteristic of attaching to the wall of cell culture flask. The cell cycle and surface markers of MSCs were identified using flow cytometry. The MSCs were pre-induced by adding DMSO, ?-Me and 5-aza for 24 h, then adding the inductive medium of H-DMEM and rh-HGF to induce their differentiation to hepatocyte like cells (HLCs). HLCs were identified by the typical morphological change and the expression of special protein with the method of immunocytochemistry. RESULTS: The MSCs derived from human fetal bone expressed adhesion molecules CD29+, CD44+, but not antigens of hematopoietic CD34, CD45, and not antigens related to GVHD, such as HLA-DR, CD80 and CD86. Exposure of these cells to above-mentioned inductive agents resulted in obvious morphological change and an increase in expression of AFP and ALB. CONCLUSION: The results suggest the existence of plentiful MSCs in human fetal bone. MSCs derived from human fetal bone can easily differentiate to HLCs, and they have a lower immunogenic nature, which may provide the ideal source for tissue engineering (bioartificial liver) for cellular therapeutics.

So far, the method of detection of patent foramen ovale (PFO) by transcranial Doppler (TCD) has had two decades of history. Standardization in contrast-enhanced transcranial Doppler US procedures for cardiac right-to-left shunt detection was proposed in the Venice Consensus Paper in 1999, and some questions were raised at the same time. Over the past 10 years, the researchers have conducted a more in depth study on the method. This article reviews the related research progress.

Aortic arch atheroma is one of the causes of embolic stroke. With the deepening of research on aortic arch atheroma, its relationship with stroke is more and more clear, particularly the aortic arch plaque thickness ≥4 mm, is associated with cryptogenic stroke, stroke recurrence, and other vascular events. Although aortic arch atheroma and clinical features of stroke have been further understood, there are still many doubts.

Adiponectin is one of the cytokines secreted by fat cells.It has a variety of physiological functions,including anti-inflammation,anti-atherosclerosis,anti-diabetes,and anti-obesity,etc.Studies in recent years have demonstrated that there are certain correlations of adiponectin with vascular risk factors and cerebrovascular disease.

According to the traditional point of view,CT and lumabar puncture are the main means in the diagnosis of subarachnoid hemorrhage(SAH).The values of conventional MRI T1-weighted imaging(T1WI)and T2 weighted imaging(T2WI)are very little in the diagnosis of SAH.With the development of MRI technique and the research and application of novel MRI sequences,the value of MRI are gradually recognized and affirmed in the diagnosis of SAH.and has shown its superiority.MRI isn't inferior to CT in the diagnosis of acute SAH.evidently superior to CT in the diagnosis of subacute,chronic and atypical SAHs and superior to CT in the diagnosis of the complications of SAH.MRI is valuable in screening for intraeranial aneurysms and postoperative follow-up.

AIM: To study the change in cognitive function in derogative state of different neurotransmitter by mensurating P300 amplitude and latency. METHODS: Acetylcholine (ACh) system was disfunctioned by severing fimbrial-fornix(FF) transaction and Norepinephrine (NE) system impaired by injection of 6-hydroxysopamine into the bilateral dorsal noradrenergic bundle in DG. Then Y-type maze test and elicitation of P3-like latency were carried out separately before and after the all models were built. RESULTS: In both experimental groups, P3-like latency was prolonged significantly compared with the control and had positive correlation with indices of Y-maze test(EN,TRT). CONCLUSION: ACh and NE are important in the production and conformity of P300.

Oxidative stress is 811 important risk factor for premature athcrosclcrosis.Itis involved in a variety of pathophysiological processes,including mitochondrial damage,freeradical release,lipid peroxidation,phospholipase activation,and infl~niatory modiator release.A growing body of research suggests that oxidative stress,oxidized low density hpoprotein,andlipoprotein-associated phospholipase A2 Play important roles in the occurrence and developmentof athcrosclcrosis.Therefore,investigating their relationship contributes to deepen theunderstanding of athcrosclerosis and take appropriate preventive measures.

A growing body of evidence demonstrates that vascular factors have involved in the occurrence and development of Alzheimer's disease.This article reviews the research progress of the AD-associated vascular factors from the aspects of AD epidemiology,pathology,clinical research,imaging,and genetics,expecting to investigate the nature of AD from all aspects through vascular factors and finding a new entry point for prevention,diagnosis and treatment of AD.

Objective To compare the efficacy of suprainguinal approach and pubic tubercle approach to obturator nerve block (ONB) in patients undergoing transurethral resection of bladder tumor.Methods Sixty ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 41-80 yr,with body mass index of 17.5-31.0 kg/m2,scheduled for elective transurethral resection of bladder tumor,were randomly divided into 2 groups (n =30 each) using a random number table:pubic tubercle approach group (group P) and suprainguinal approach group (group S).Nerve blocks were performed using a 100-mm insulated needle for ONB (21-gauge) under the guidance of a nerve stimulator.In group P,the insertion point of the needle was 1.5 cm lateral and 1.5 cm inferior to the pubic tubercle.In S group,the insertion point of the needle was at the midpoint of the line drawn in the inguinal crease between the femoral artery and the inner border of the adductor longus tendon and the needle was advanced 3 cm cephalad in the major axis of thigh.The number of puncture eliciting contraction of adductor muscle,time taken to elicit contraction of adductor muscle starting from onset of puncture,depth of puncture,and highest visual analog scale (VAS) pain scores during application of the block were recorded.The myodynamia of adductor muscle was evaluated.The development of complications was also recorded.Results Compared with group P,the number of puncture,highest VAS scores,and myodynamia of adductor muscle at 4 and 6 min of blockade were significantly decreased,the time taken to elicit contraction of adductor muscle was shortened,and the success rate of puncture at first attempt was increased in group S (P ＜ 0.05 or 0.01).There was no significant difference in the incidence of puncture point bleedings between the two groups (P ＞ 0.05).Conclusion The suprainguinal approach for ONB offers more accurate location,faster onset,lighter degree of noxious stimulation and better safety than the pubic tubercle approach in patients undergoing transurethral resection of bladder tumor.