Nitric oxide (NO) is the most important known endogenous vasodilator factor. The competitive inhibitor asymmetric dimethylarginine (ADMA) of endothelial nitric oxide synthase (NOS) inhibits NO synthesis, which makes NO/NOS pathway to be obstructed and the reduction of NO synthesis. The studies in recent years have suggested that ADMA is as-sociated with the occurrence and development of diabetes with cerebrovascular disease. It has provided new insights into further clarifying the mechanism of the disease.

Diabetes associated large vascular disease is a major threat to type 2 diabetes mellitus,its main pathological mechanism is atherosclerosis.Carotid intima-media thickness (CIMT) detected using high resolution ultrasound technique can be used as an alternative indicator of subclinical atherosclerosis.It has been confirmed that it is a strong predictor of cardio-cerebrovascular diseases.This article focuses on the latest research progress of the CIMT-associated risk factors in patients with type 2 diabetes mellitus.

AIM: To investigate the chemical constituents of the plant drug Cornus officinalis Sieb et Zucc. which is widely used in Chinese traditional medicine, having actions of invigorating the liver and kidney, strengthening the body, and of an astringent, etc. METHODS: A sedoheptulose gallate was isolated from the water extracts of fruits of C.officinalis using various chromatographies. The structure determination was based on spectral (UV, IR, 1H & 13CNMR and MS) and chemical evidence. RESULTS: Its structure was characterized to be 7-O-galloyl-D-sedoheptulose (I). The proportion of its three major conformation forms of β-F, α-F and α-P in aqueous solution was estimated to be 57:24:19 according to their C-1 peak heights in the 13CNMR spectrum. CONCLUSION: I was found in natural world for the first time and its β-D-heptufuranosyl form was the predominant existing tautomer in its equilibrated aqueous solution according to NMR determination.

OBJECTIVE: To evaluate the safety and efficacy of Wuling Capsule combined with Deanxit in treating post-stroke depression (PSD). METHODS: One hundred and fourteen patients with PSD were randomly divided into Wuling Capsule-treated group (n=39), Deanxit-treated group (n=37) and Wuling Capsule plus Deanxit-treated group (n=38). Patients in Wuling Capsule-treated group were administered with three Wuling Capsules three times a day, and patients in Deanxit-treated group were administered with Deanxit 10.5 mg twice daily, while patients in the Wuling Capsule plus Deanxit-treated group were administered with both Wuling Capsule and Deanxit. Patients in the three groups were all treated for six weeks. Treatment efficacy was evaluated with Hamilton Depression Scale (HAMD) and the side effects were evaluated with Treatment Emergent Symptom Scale (TESS) before treatment and after 2-, 4-, and 6-week treatment. The blood and urine routine examinations were performed, and the hepatorenal functions and electrocardiogram were examined as well. RESULTS: There was no statistical difference in the total efficacy rate between Wuling Capsule-treated group and Deanxit-treated group (64.1% vs 64.9%, P>0.05), but the total efficacy rate of Wuling Capsule plus Deanxit-treated group was higher than that of the monotherapy (89.5% vs 64.1%, 89.5% vs 64.9%, P<0.05). There were no significant side effects in Wuling Capsule-treated group, while the incidence of side effects was 9% in both groups administered with Deanxit. CONCLUSION: The efficacy of Wuling Capsule plus Deanxit is better than that of the monotherapy in treating PSD.

Objective To construct pEGFP-C2-AQP4-M23 plasmid and to detect its expression in CTX-TNA2 cells in order to study the effect of AQP4 on astrocytes in hypoglycemia. Methods AQP4 gene obtained from SD rats by RT-PCR was cloned into pEGFP-C2 plasmid. The recombinant plasmid was transfected into CTX-TNA2 cells, then treated with low glucose. The expression and effect of AQP4 on CTX-TNA2 cells were examed with confocol. Results PCR and enzyme digestion showed AQP4 size was right; confocol demonstrated that AQP4 was expressed on the membrane of CTX-TNA2 cells, and the surfacial area of CTX-TNA2 cells with AQP4was larger than those without AQP4 in hypoglycemia. Conclusion pEGFP-C2-AQP4-M23 plasmid was successfully constructed and expressed in the CTX-TNA2 cell membrane and AQP4 plays an important role in cell edema in hypoglycemia.

Objective To analyse the mutation of pathogenic gene TSC2 in tuberous sclerosis complex (TSC). Methods Using polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP), all the 41 exons of TSC2 gene were analyzed in 4 TSC cases(include 1 suspect case) from one family and 1 sporadic TSC case ,and compared with the kin familial controls and kinless normal controls. Results Missense mutation on exon33 1346S→P (4037T→C) of TSC2 was found in 4 familial cases, and no mutation of TSC2 gene was found in the sporadic case and all the health controls. Conclusion Missense mutation on exon33 (1346S→P,4037T→C)is a new discovery in TSC2 gene of patients with TSC.

Objective:To study the effect of Mg 2+ on glutamate and energy metabolites during focal cerebral ischemia and reperfusion in rats. Methods: Twelve male Wistar rats were divided into 2 groups(n=6):magnesium sulfate(100 mg/kg, i.p.) group and saline group.Cerebral ischemia was produced by occlusion of middle cerebral artery with a nylon thread for 60 min and followed by 60 min reperfusion.Microdialysis probes were stereotaxically implanted into the cortex; dialysates were collected every 15 min to determine the concentrations of glucose, lactic acid and glutamate. Results: There was a dynamic decrease of glucose and an increase of lactic acid and glutamate during ischemia and reperfusion in saline group.Glucose decreased slightly in magnesium sulfate group during ischemia and recovered to normal rapidly during reperfusion. The lactic acid levels in magnesium sulfate group were lower than that in saline group during early stage of ischemia(0-15 min) and reperfusion.There were significant attenuation in the elevation of glutamate during ischemia and reperfusion when magnesium sulfate was administered and recovered to normal after 30 min of reperfusion. Conclusion: The preservation of cellular energy metabolism,the decrease of lactacidosis and attenuation of glutamate level during ischemia and reperfusion may contribute to the neuroprotective effects of Mg 2+ .

AIM: To study factors affecting the stability of nylon monofilament for intraluminal middle cerebral artery occlusion in rats.METHODS:Successful rates and infarct volume of ischemic model were compared by polyvinyl alcohol (PVA) coated and silicon coated nylon monofilament intraluminal occlusion of middle cerebral artery under condition of ligation and without ligation of peterygopalatine artery.RESULTS:The successful rates were 60% and 53% in two groups under condition of ligation of peterygopalatine artery, and 20% and 27% in other two groups under condition of without ligation of peterygopalatine artery respectively. The intracranial length of nylon monofilament were about 7 mm in successful model and 4 mm in failure model. Animals in the PVA coated nylon monofilament group showed neurological dificit signs earlier, and had a significantly larger infarct volume at 12 hours of ischemia than those in the silicon coated group.CONCLUSIONS:The ligation of peterygopalatine artery is critical in the success of making this kind of ischemic model. The appropriate position of nylon monofilament entering crania and the good expansibility of PVA play an important role in occlusion of blood flow. Because of the relatively lower successful rate, a new substitute with unique quality, proper hardness and better elasticity needs to be explored in the future.

AIM: To study the difference in glucose and lactate levels between brain extracellular fluid (ECF) and plasma in rabbits in the different blood glucose levels. METHODS: Using intracerebral microdialysis technology, brain ECF levels of glucose and lactate were measured in every 10 min under basal conditions and during a hyperglycemia-hypoglycemia clamp study. RESULTS: Under basal condition, brain ECF glucose levels were markedly lower than ambient plasma levels (30% of plasma), whereas ECF lactate levels were substantially higher (165% of plasma). During the hyperglycemia-hypoglycemia clamps, the relationship between plasma and ECF levels of glucose remained similar, but changes in ECF glucose lagged about 30 min. There were no substantially changes in ECF levels of lactate during dynamical study. CONCLUSION: There are striking differences in glucose and lactate levels between brain ECF and plasma. Lactate may involve in the metabolic process of central nervous system.

Objective To investigate the feasibility of establishing aneurysm model at the carotid artery bifurcation in experimental dogs. Methods New aneurysm model at the common carotid artery (CCA) bifurcation was established in 18 experimental dogs, which were randomly and equally divided into study group (n =9) and control group (n=9). In the dogs of the study group, the bifurcation top was treated with elastase, while in the dogs of the control group the bifurcation top was treated with saline. Angiography was separately performed immediately after, and at 12 and 24 weeks after the operation to observe the changes of the aneurysm top. Pathological examination was separately carried out at 12 and 24 weeks after the operation. Results Angiography showed that nascent aneurysm formation (mean diameter of 3.2 ± 0.4 mm) was demonstrated at the arterial bifurcation top in 5 dogs of the study group; while no nascent aneurysm at the arterial bifurcation top was observed in the control group. During the follow-up period, no rupture of the nascent aneurysm occurred in the study group. Pathological examination revealed that discontinued internal elastic membrane, elastic fiber fracture, thinning muscle layer and reduction of smooth muscle cells were detected in the aneurysm at bifurcation top in the study group; when compared with those in the control group, the difference was statistically significant (P< 0.001). Conclusion The elastase-induced digestive degeneration of artery wall can cause new aneurysm formation in the newly-established aneurysm located at carotid artery bifurcation in experimental dogs.