Vascular cognitive impairment refers to the learning and memory impairments caused by cerebrovascular lesions.Studies in recent years have shown that oxidative stress plays an important role in vascular cognitive impairment.This article reviews the mechanisms and the prevention and treatment of oxidative stress in vascular cognitive impairment.

Objective To develop a sandwich enzyme-linked immunosorbent assay ( ELISA) for the determination of a humanized antibody MIL50.Methods RiVax, a mutant of RTA (a chain of ricin) expressed in E.coli, was used as the coating protein.Horseradish peroxidase (HRP) labeled IgG of goats against humans was used to determine MIL 50 captured by RiVax coated on the plate.Results Compared with ricin, RiVax could bind well with MIL50,indicating it could be used as a coating protein to determine MIL50 instead of holotoxin.Using this method, the detective limit of MIL50 in PBST (PBS containing 0.1%Tween 20) could be as low as 0.030 mg/L.The absorbance value of ELISA for MIL50 in the ser-um and homogenate of the liver , spleen, lung, kidney, muscle of rats was lower than that in PBST .Conclusion The sandwich ELISA is a sensitive method for the analysis of distribution of MIL 50 in rat tissues.

Objective To explore the correlation between executive function and white matter lesions (WML) and the diagnostic value by clock drawing test(CDT) in patients with vascular dementia (VaD). Methods Twenty-seven VaD patients and twenty-five normal control subjects were evaluated with CDT to assess the executive function. CDT was scored according the four point method. Age-related white matter change rating scale (ARWMCrs) was used qualitatively to measure and locate the WML by cranial MRI scanning. Results 1. The scores of CDT in normal cognition health and VaD were ( 3.88 ± 0. 33 ) and ( 1.74 ± 0. 98 ). The difference between two groups was statistically significant (P＜0. 01 ). The humerous part and the point part were the earliest to decline in the VaD Patients. The scores of WML were (5.12 ± 4. 19) and ( 11.19± 3.09), respectively. There was significant difference between two groups(P ＜ 0. 01 ). The scores of CDT had significant positive correlation with MMSE scores and negative correlation with WML scores (P ＜ 0. 01 ). Conclusion The executive functional impairment in patients with VaD could be associated with the degree of WML.

Objective To compare the applicability of the Beijing Version of the Montreal Cognitive Assessment (MoCA) and the Mini Mental State Examination (MMSE) in screening for cognitive impairment in patients with acute ischemic stroke for 2-3 weeks.Methods MoCA and MMSE were conducted in 201 patients with acute ischemic stroke within 2 to 3 weeks after the onset of stroke.With MoCA＜23 and MMSE ＜26 as the cut off value,we assessed the clinic effect of the MoCA and MMSE and explored the correlation between two instruments.Results The average scores of MoCA and MMSE scale were (20.5±4.3) and (25.4±3.5) points.The prevalence of cognitive impairment evaluated with MoCA and MMSE were 57.2％and 43.3％,respectively.MoCA showed significant correlation with MMSE score (Pearson's correlation coefficient=0.833,P＜0.001),and an agreement with Kappa values of 0.532 (P＜0.01) in screening for cognitive impairment.Conclusions The prevalence of cognitive impairment assessed with MoCA is higher than that of with MMSE when using MoCA＜23 and MMSE＜26 as the cut off values.Both instruments show a good agreement for screening cognitive impairment in acute ischemic stroke within 2 to 3 weeks following the disease onset.

Halohydrin dehalogenase is of great significance for biodegradation of the chlorinated pollutants, and also serves as an important biocatalyst in the synthesis of chiral pharmaceutical intermediates. A putative halohydrin dehalogenase (HheTM) gene from Tistrella mobilis KA081020-065 was cloned and over-expressed in Escherichia coli BL21 (DE3). The recombinant enzyme was purified by Ni-NTA column and characterized. Gel filtration and SDS-PAGE analysis showed that the native form of HheTM was a tetramer. It exhibited the highest activity at 50 degrees C. The nature and pH of the buffer had a great effect on its activity. The enzyme maintained high stability under the alkaline conditions and below 30 degrees C. HheTM catalyzed the transformation of ethyl(S)-4-chloro-3-hydroxybutyrate in the presence of cyanide, to give ethyl (R)-4-cyano-3-hydroxybutyrate, a key intermediate for the synthesis of atorvastatin.
3-Hydroxybutyric Acid ; chemistry ; Bacterial Proteins ; genetics ; metabolism ; Cloning, Molecular ; Escherichia coli ; Hydrolases ; genetics ; metabolism ; Hydroxybutyrates ; chemistry ; Recombinant Proteins ; genetics ; metabolism ; Rhodospirillaceae ; enzymology ; genetics

OBJECTIVE To investigate the immunogenicities of Poria cocos polysaccharides, PCP-Ⅰand PCP-Ⅱ, as a vaccine adjuvant. METHODS ①Keyhole limpet hemocyanin (KLH) was linked to PCP-Ⅰor PCP-Ⅱrespectively to prepare immuno-antigen KLH-PCP-Ⅰor KLH-PCP-Ⅱ. Bovine serum albumin (BSA) was also linked to PCP-Ⅰor PCP-Ⅱrespectively to prepare screening-antigen. Rabbits were immunized with KLH-PCP-Ⅰor KLH-PCP-Ⅱplus Freund adjuvant by intradermal injection twice, and serum specific antibody titers were determined by ELISA. ②BALB/c mice were immunized with PCP-Ⅰ or PCP-Ⅱ alone intramuscularly twice, and serum polysaccharide antibody titers were determined by ELISA.③BALB/c mice were co-immunized intramuscularly or subcutaneously with PCP-Ⅰor PCP-Ⅱplus hepatitis B surface antigen (HBsAg) or porcine reproductive and respiratory syndrome virus inactivated vaccine (PRRSV) twice, and serum polysaccharide-antibody titers were determined by ELISA. RESULTS ①Serum anti-KLH and anti-polysaccharides (PCP-Ⅰor PCP-Ⅱ) antibodies were pro?duced after rabbits were immunized with KLH-PCP-Ⅰor KLH-PCP-Ⅱplus Freund adjuvant twice.②Serum anti-PCP-Ⅰor anti-PCP-Ⅱantibodies were not found after mice were immunized with PCP-Ⅰand PCP-Ⅱalone twice.③After mice were immunized with HBsAg or PRRSV plus PCP-Ⅰor PCP-Ⅱtwice, serum anti-PCP-Ⅰor anti-PCP-Ⅱantibodies were not found. CONCLUSION PCP-Ⅰand PCP-Ⅱshow weak immunogenicity, which may be quite safe as a vaccine adjuvant.

Objective To investigate the lesionsin theleft thalamus and to explore their correlation with executive functionin patients with subcortical ischemic vascular disease(SIVD)by using 1H magnetic resonance spectroscopy (1H-MRS) and diffusion tensor imaging (DTI). Methods Fourteen patients with vascular dementia (VaD), 14 patients with vas-cular cognitive impairment without dementia(VCIND)and 14 normal controls (NC) were recruited. The quantitative analy-sis of N-acetylaspartate (NAA), Choline (Cho), myoinositol (MI) and Creatine (Cr) resonance signals in region of interests (ROI) in the left thalamus were measured. Fractional anisotropy (FA) and mean diffusivity (MD) values in the same region were examined by using DTI. The relationship were analyzedamong the MRS, DTI ratios and cognitive impairment reflect-ed in MMSE and trail making test(TMT). Results The NAA/Cr ratio showed a gradual decrease in the left thalamus of VaD andVCIND patients compared with controls(F=3.656, P=0.038). There was no significant difference in NAA/Cr ra- tiobetween VaD and VCIND patients.Compared with controls, patients with VaD and VCIND demonstrated increased MD value in the left thalamus(F=3.882, P=0.030).There was no significant difference in MD value between VaD and VCIND patients (P>0.05). There were no correlations between NAA/Cr, MI/Cr, Cho/Cr value and DTI parameters in the ROI (P>0.05). TMTb time was positively associated with Cho/Cr(r=0.520,P=0.001 ) and with MD value in the left thalamus (r=0.305, P=0.044). Conclusions Combination of 1H-MRS with DTI can provide the valuable informationon the potential lesions in the thalamus in patients with SIVD. The Cho/Cr and MD values in the leftthalamus may be correlated with ex-ecutive function.

Objective To investigate the value of electronic bronchoscopy in the diagnosis of children respiratory diseases. Methods The electronic bronchoscopy results in 400 children with respiratory disease were retrospectively analyzed. Results In 400 children, there were 246 cases with simple endobronchial inflammation, 67 cases with bronchial malacia, 38 cases with bronchial stenosis, 23 cases with bronchial foreign , 4 cases with tracheal bronchus, 4 cases with epiglottic cyst, 3 cases with bronchiectasis, 3 cases with endobronchial granulation, 3 cases with laryngomalacia, 2 cases with vascular ring compression of the trachea, 2 cases with laryngeal web, 1 case with subglottic cyst, 1 case with subglottic neoplasm, 1 case with tracheoesophageal fistula, 1 case with bronchial atresia (left) and 1 case with trachea cyst. All the children had no serious complications. Conclusions Electronic bronchoscopy can effectively improve the level of diagnosis and treatment of children' s respiratory system disease, and it is worth of clinical promotion.

Objective:To explore the correlation between middle cerebral artery (MCA) pulsatility index (PI) and total magnetic resonance imaging (MRI) burden in elderly patients with cerebral small vessel diseases (CSVD).Methods:A total of 203 CSVD inpatients aged 60 years and above who were hospitalized in the Department of Neurology of Hebei General Hospital from March 2017 to December 2020 were enrolled. The clinical data, transcranial Doppler ultrasound parameters and brain MRI data were collected. According to the total burden score, the patients were divided into low burden group (0-1 point) and high burden group (2-4 points). Univariate and multivariate Logistic regression analysis was used to analyze the correlation between MCA PI and total MRI burden in the elderly patients with CSVD. Subsequently, the receiver operating characteristic curve was used to evaluate the value of MCA PI for predicting the high MRI burden of CSVD in the elderly.Results:Hypertension ( OR=2.569, 95% CI 1.068-6.182, P=0.035), systolic blood pressure ( OR=1.033, 95% CI 1.006-1.061, P=0.016), creatinine ( OR=1.044, 95% CI 1.009-1.079, P=0.013) and MCA PI ( OR=1.125, 95% CI 1.087-1.166, P<0.001) were independently correlated with the increasing total MRI burden in the elderly patients with CSVD. Spearman rank correlation analysis revealed that there was strong and positive correlation between MCA PI and high MRI burden in the elderly patients with CSVD ( r=0.65, P<0.001). The analysis showed that when the cut-off for MCA PI was 1.11, it could identify high MRI burden of CSVD in the elderly. The area under the curve was 0.908 (95% CI 0.864-0.953, P<0.001). The sensitivity and specificity were 0.852 and 0.880, respectively. The positive predictive value was 92.38%, and the negative predictive value was 77.70%. Conclusion:The MCA PI is positively correlated with total MRI burden in the elderly patients with CSVD, and has a higher value in predicting the total MRI burden in the elderly CSVD patients, which probably bring brighter prospects for its clinical application.

Objective To investigate the effect of electroacupuncture (EA) at Shenting (DU24) and Baihui (DU20) acupoints on hippocampal synaptic plasticity and learning and memory function, and its possible mechanism in rats with cerebral ischemia-reperfusion. Methods Thirty-two male adult Sprague-Dawley rats were randomly divided into sham group (n=8), model group (n=8), electroacupuncture (EA) group (n=8) and non-acupoint group (n=8). The model group, EA group and non-acupoint group were performed with left middle cerebral artery occlusion (MCAO). The EA group received electroacupuncture at Shenting and Baihui, while the non-acupoint group received electroacupuncture at two fixed non-acupoints from bilateral ribs, for fourteen days. Then they were tested with Morris Water Maze test, and their synaptic structure of hippocampal neurons was observed with transmission electron microscope. The level of total LIM-domain containing protein kinase 1 (T-LIMK1) and LIM-domain containing protein kinase 1 phosphorylation (p-LIMK1) were detected with Western blotting. Results Compared with the sham group, the latency increased (t>6.789, P<0.01) and the frequence crossing platform decreased (t= 8.695, P<0.001) in the model group, while the number of synapse in hippocampal neurons decreased, and the level of T-LIMK1 (t=7.568, P< 0.01) and p-LIMK1 (t=8.874, P<0.001) decreased. Compared with the model group, the latency decreased (t>4.938, P<0.01) and the frequence crossing platform increased (t=- 7.891, P<0.001) in the EA group, while the number of synapses increased, and the level of T-LIMK1 (t=-6.473, P<0.01) and p-LIMK1 (t=-6.579, P<0.01) increased. There was no significant difference between the the non-acupoint group and the model group in all the indices (P>0.05). Conclusion Electroacupuncture at Shenting and Baihui can improve the ability of learning and memory in rats with cerebral ischemia-reperfusion, which may relate with the increase of LIMK1 phosphorylation and hippo-campal synaptic plasticity.