Lactide一glycolide copolymerization with stannous octanoate as an initiator and dedecanolas regulator was carried out.The effect of reaction condition such as reaction time,temperature, initiatorconcentration, regulator and monomer ratbonpolymerization conversion,molecular weight and its distrbu-tion were investigated.The obtained results show that the finest reaction condition are initiator 0. 075%,ternperature 170℃ and reaction time 6hr.At this reaction condition,both molecular weight and polymer-ization conversion obtained are vecy high.

Doxorubicin loaded micelles were prepared by film-hydration method using stearyl sulfadiazine (SA-SD) which is pH sensitive, methoxy (polyethylene glycol)-2000-1, 2-dioleoyl-sn-glycero-3-phosphoethanolamine (mPEG-DOPE) and transactivator of transcription (TAT) peptide conjugated PEG-DOPE. Mean diameter of the pH-sensitive micelles was about 20 nm with a (99.1 +/- 2.1) % drug entrapment efficiency at pH 7.4. Flow cytometry studies revealed that the simple TAT micelles was taken up rapidly at the same level at pH 6.8 and pH 7.4. However, the pH-sensitive micelles entered the tumor cell less at pH 7.4 and significantly increase at pH 6.8. After 1 h incubation at pH 6.8, the amount of the pH-sensitive micelles taken up by cancer cell 4T1 was almost similar to simple TAT micelles. The confocal microscopy indicated that the pH-sensitive micelles entered the 4T1 cells at pH 6.8 more than at pH 7.4. It was indicated that the pH-sensitive micelles could shield TAT peptide at normal pH 7.4 and deshield it at pH 6.8. Hence, TAT peptides lead the drug-loaded micelles into the tumor cells and killed them selectively. The pH-sensitive micelle may provide a novel strategy for design of cancer targeting drug delivery system.

Objective To investigate the changes of the electrocardiograms (ECG) and the cardiac markers in patients with acute insular infarction,and analyze the relationship between them and the prognosis.Methods A total of 202 patients with acute middle cerebral artery territory infarction (patients group) and 150 control subjects (control group) was selected in this study.Patients included insular infarction (insular infarction group,136 cases),non-insular infarction (non-insular infarction group,66 cases),left-side insular infarction(71 cases) and right-side insular infarction(65 cases).ECG recordings and plasma cardiac troponin I (cTnI),creatine kinase-MB (CK-MB) were measured and compared.Death in 6 months was followed-up.Results There was significant difference in the incidence of abnormal changes of ECG and plasma cTnI,CK-MB increasing between patients group and control group (P ＜0.01).The incidence of abnormal changes of ECG and fatality rate were higher in insular infarction group than those in non-insular infarction group [80.88％(110/136) vs.46.97％(31/66) and 11.76％ (16/136) vs.3.03％ (2/66),P ＜ 0.05 or ＜ 0.01].The incidences of ectopy and prolonged QT were higher in right-side insular infarction patients than those in left-side insular infarction patients [44.62％(29/65) vs.11.27％ (8/71),P ＜0.01 ; 55.38％ (36/65) vs.35.21％ (25/71),P ＜ 0.05].The incidences of sinus bradycardia and ST segment deviation were higher in left-side insular infarction patients than those in right-side insular infarction patients [22.54％(16/71) vs.7.69％(5/65),P ＜ 0.05 ;47.89％(34/71) vs.13.85％ (9/65),P ＜ 0.05].The increased rates plasma cTnI and CK-MB level were mainly seen in insular infarction [insular infarction group:47.79％ (65/136),34.56％ (47/136); non-insular infarction group:4.55％ (3/66),1.52％ (1/66),P ＜ 0.01].The incidence of plasma cTnI increasing in right-side insular infarction patients was higher than that in left-side insular infarction patients [67.69％(44/65) vs.29.58％(21/71),P＜ 0.05].There was no significant difference in the incidence of plasma CK-MB increasing between left-side insular infarction patients and right-side insular infarction patients(P ＞ 0.05).The fatality rates in plasma cTnI,CK-MB increasing patients were higher than those in normal plasma cTnI,CK-MB patients [16.18％ (11/68) vs.5.22％ (7/134),P ＜0.05;29.17％ (14/48) vs.2.60％ (4/154),P ＜0.01].Conclusions The effects of acute hemispheric cerebral infarction on heart are mainly associated with destruction of insula.Patients with insular infarction have more abnormal changes of cardiac markers and ECG,which is correlated with poor prognosis.

Choroid Plexus Neoplasms ; pathology ; Female ; Humans ; Infant ; Lateral Ventricles ; pathology

Objective To investigate the clinicopathologic features of the brain tissue from multilobar resection or hemispherectomy for refractory epilepsy. Methods The clinical and pathologic findings of 46 cases seen at Xuanwu hospital from 2005 to 2009 were reviewed retrospectively. Results The mean age of seizure onset and disease duration were 3.9 years and 10.2 years, respectively. There were 33 cases of hemispherectomy and 13 cases of multilobar resection. Temporal lobe abnormality was seen in all cases. The pathologic subgroups were as follows: ulegyria (31/46), malformation of cortical development (MCD, 7/46 ) and infection (8/46). Microscopic examination of ulegyria showed cortical architectural disturbances, neuronal loss, reactive gliosis and appearance of corpora amylacea. We also noted deposition of hemosiderin (13 cases), calcification (9 cases) and island-like neurons (5 cases). All ulegyria cases were accompanied by varying degree of cortical dysplasia, and hippocampus sclerosis were identified in 7 cases. MCD comprised of 5 cases of focal cortical dysplasia ( FCD), including 3 cases of FCDⅠB, 1 case of FCDⅡA and 1 case of FCDⅠA, 1 case of polymicrogyria and 1 case of porencephaly. Among 8 infection eases, there were 5 cases of Rasmussen encephalitis ( RE), l case of cysticercosis, 1 case of tuberculous meningitis and l case of Cytomegalovirus encephalitis. Conclusions The most common pathological category of specimens from hemispherectomy or multilobar resection is ulegyria with obvious temporal lobe abnormality. This is followed by MCD ( with FCDⅠB as the main type) and central nervous system infection (RE as the most frequent abnormality).

Objective To investigate the elinieopathologie features of refractory epilepsy. Methods The clinical and pathologic features of refractory epilepsy of 273 cases undergoing surgical treatment in Xuanwu Hospital from January 2005 to December 2007 were reviewed retrospectively. Results The mean age of seizure onset and disease duration were 11.0 years and 11.2 years respectively. The following pathologic subgroups were identified: malformation of cortical development (MCD, 158/273) including focal cortical dysplasia (FCD) type Ⅰ (104, the mean age of seizure onset and disease duration were 11.1 years and 11.2 years respectively), FCD type Ⅱ (30, the mean age of seizure onset and disease duration were 7. 9 years and 12. 7 years respectively) , mild MCD (6) , tuberous sclerosis complex (6) and other types (9) , brain turnouts (26/273, the mean age of seizure onset and disease duration were 14. 5 years and 6. 3 years respectively), ulegyria (63/273), brain infections (13/273), vascular malformation (3/273), cyst (3/273), cholesteatoma (1/273) and other unknown types (6/273). Dual pathology was identified in 31 of 158 MCD cases. Eighty-six of 134 (64. 2%) FCD cases were type Ⅰ B predominantly seen in temporal lobe. Twenty of 26 (76. 9%) brain tumours were mixed neuronal-glial tumours predominantly located in temporal lobe. Cortical dysplasia was often seen in these cases. Conclusions The 3 most common causes of refractory epilepsy are MCD, ulegyria and brain tumours. The predominant subtype of FCD is type Ⅰ B often located in temporal lobe, in which associated hippoeampal sclerosis is often seen. Brain tumors in patients with refractory epilepsy are almost benign neoplasms located in temporal lobe, in which the most frequent type is mixed neuronal-glial tumour.

Objective To study the locations of P-glycoprotein(P-gp),multi-drug resistanceassociated protein (MRP) and lung resistance.related protein(LRP)in brain tissue of focal cortical dysplasia (FCD) and to compare the quantity of these proteins in different brain tissues in an effort to study the mechanism of refractory epilepsy and to provide theoretical basis for medical treatment in patients with epilepsy.Methods The brain tissues of 16 cases with refractory epilepsy were collected during surgery,including 8 cases of focal cortical dysplasia type Ⅰ(FCD Ⅰ)and 8 cases of focal cortical dysplasia type Ⅱ (FCD Ⅱ) Five cases of glioma without history of epilepsy were included as the control group.Envision method was used to observe the location and intensity of expression of these three proteins.Western-Blot was used to analyze these proteins quantitatively.Results In brain tissue,the locations of P-glycoprotein,multi-drug resistance-associated protein and lung resistance-related protein were difierent.P-gp located mainly in capillary endothelial cells;MRP in neurons components;the location of LRP included capillary endothelial cells,balloon cells and the matrix of lesions.The expressions of three proteins in brain tissue of FCD were significantly higher than in control group(P-gp:0.520 ±0.121,MRP:0.132±0.018,LRP:0.092.±0.018,U=0.000,P<0.01).The expressions of P-gp and LRP in lesions of FCD Ⅱ(3.809 ±0.842 and 0.655±0.303,respectively)were higher than that in surrounding regions(2.636 ±0.622 and 0.290±0.096,U value were 6.000 and 4.500,both P<0.01).Conclusions P-gp,MRP and LRP expressed at different position of focal cortical dysplasia,suggesting that their roles were distinctive.

Objective To compare the expression and distribution of drug resistance proteins Pglycoprotein (P-gp) and lung resistance protein (LRP) in brain tissues of patients with refractory epilepsy and to investigate the relationship between expression of drug resistance proteins and concentration of antiepileptic drug carbamazepine (CBZ).Methods We included the brain tissues of 26 cases with refractory epilepsy who had in the experiment.They had following pathologic diagnosis: focal cortical dysplasia (FCD) Ⅰb (n =10),FCD Ⅱ a (n =4),FCD Ⅱb (n =2) and brain tumorsincluding ganglioglioma (n =6) and dysembryoplastic neuroepithelial tumor(n =4).Immunohistochemistry staining using EnVision system was used to reveal the expression location of P-gp and LRP,and Western blot in SDS-polyacrylamide gel was used to quantitatively analyze the expression of P-gp and LRP.Fluorescence polarization immunoassay was used to determine concentration of CBZ.Results Both P-gp and LRP performed(μg/ml) prominent overexpression in brain tissues of patients with refractory epilepsy,especially in the lesions of both FCD type Ⅱ (P-gp: 2.593 ±0.829 vs 1.711 ±0.292,t =-2.201,P=0.028;LRP:1.352 ±0.445 vs 1.179 ±0.593, t =-2.516,P =0.028, respectively)and tumor(P-gp:1.567 ±0.092 vs 0.775 ± 0.101, t =2.698, P =0.024; LRP: 1.091 ± 0.239 vs 0.825 ± 0.297, t =3.997, P =0.003respectively).The concentration of CBZ in lesions of brain tumors were lower than which in surrounding regions(0.848 ±0.726 vs 0.948 ±0.785, t =-3.056,P =0.014), while P-gp and LRP were higher than which in surrounding regions in 80％ cases.There was no relationship between expression of drug resistance proteins and concentration of CBZ.Conclusions In processing of drug resistance, P-gp and LRP play important roles.However, there is no correlation between expression of drug resistance proteins and concentration of CBZ, suggesting epilepsy drug resistance to be a complicated mechanism.

Aim To establish the methods for exosomes isolation from the cell culture medium based on the principle of polyethy-lene glycol (PEG) precipitation combined with ultra-high speed centrifugation. Methods Exosomes were extracted by different centrifugation, PEG6000 precipitation combined with ultra-high speed centrifugation and EXO Quick kit,respectively. The mor-phology and particle size of exosomes were analyzed by transmis-sion electron microscopy,NanoSight ZS and Nano-particle track-er(NTA). Western blot assay was used to identify if the extrac-tion were exosomes. Results According to PEG6000 precipita-tion combined with ultra-high speed centrifugation method, the exosomes were successfully isolated from the culture medium. The morphology and particle size of exosomes,the exosomes iso-lated from PEG6000 precipitation combined with ultra-high speed centrifugation were equal to those of the ultra-high speed centrifugation but smaller to EXO Quick kit. What's more, the results of transmission electron microscopy showed that the three methods had typical discoid vesicles. Conclusion The im-provement of the exosome isolation from cell culture medium is convenient,easy and cheap.