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Objective: To investigate the correlation between the diffusion anisotropy of the white matter fibers and the cognitive function in patients with leukoaraiosis (LA)., Methods: Thirty-one LA patients were enrolled in this study, including 13 with grade LA-1 (mild), 12 with grade LA-2 (moderate) and 6 with grade LA-3 (severe) condition. The control group consisted of 18 subjects who were free of obvious clinical symptoms or had only mild dizziness and headache but with negative history for neural system diseases and in the absence of cognitive dysfunction, brain trauma, positive signs in neurological examinations, or abnormities in MRI examination. The Mini-mental State Examination (MMSE) was applied to evaluate the patients' cognitive function. The LA patients underwent examination with diffusion tensor MR imaging (DTI), and the FA and MD values in the normal-appearing white matter (NAWM) were measured., Results: The cognitive function of the LA patients tended to decline with the decrease of the MMSE scores, and their scores for time orientation, place orientation and calculation were significantly lower than those of the control group (P<0.05). No significant difference was found in memory, language and comprehensive abilities between the LA and control groups. In LA-1, LA-2 and total LA cases, the FA value in the NAWM was positively, and the MD value inversely, correlated to the cognitive function with correlation coefficients ranging from 0.5 to 0.8 (P<0.05)., Conclusion: The DTI parameters of NAWM region are correlated to the cognitive function of LA patients. DTI is far more sensitive than MRI in evaluating cognitive dysfunction in LA patients.

Objective: To explore the value of lower-limb short latency somatosensory evoked potentials (SLSEP) in predicting early death in patients with massive cerebral infarction., Methods: Forty-eight patients of massive cerebral infarction were admitted in the Neurological Intensive Care Unit (NICU) between March 2008 and March 2009, and Glasgow-Pittsburgh coma scale (GPCS) and SLSEP were recorded and graded within 24 h after admission. The patients were divided into survival and death groups (including brain death) according to their short-term prognosis. The correlations of SLSEP and GPCS to the mortality were assessed., Results: A significant correlation was found between SLSEP and the mortality in patients with massive cerebral infarction (r=0.484, P<0.001). The positive predictive value of the SLSEP grade 3 to death was 100%, and the patients with malignant middle cerebral artery infarction (mMCAI) appeared to have a 100% mortality., Conclusion: SLSEP grade 3 can be a highly specificity in predicting early death in patients with massive cerebral infarction, and it is also of value in determining the timing of surgical intervention of mMCAI.

Objective: To study the relationship between cystatin C and cerebral infarction and explore the role of cystatin C in the protection against cerebral infarction., Method: Eighty-three patients with cerebral infarction and 71 randomly selected age- and gender-matched patients in the Department of Neurology (control group) were enrolled in this study. Fasting whole blood (3 ml) was obtained from the patients in both groups and the sera were separated to determine the levels of cystatin C using particle reinforced immunoturbidimetric assay., Results: The serum cystatin C level was significantly lower in the cerebral infarction group than in the control group (1.62-/+0.31 vs 2.23-/+0.22 mg/L, P<0.01)., Conclusions: Cystatin C is closely related to cerebral infarction probably as a protective factor against cerebral infarction.

Objective: To investigate the association of IL-1beta+3953, TNFbeta+252 and IL-10-592 polymorphisms with serum lipoprotein levels in Chinese Han population in Guangdong Province., Methods: A total of 428 individuals of Han nationality from Guangdong Province were enrolled in this study. The genotypes of IL-1beta+3953, TNFbeta+252 and IL-10-592 sites were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The serum concentrations of total cholesterol (TC), TG, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and very low density lipoprotein (VLDL) were determined using an automatic biochemistry analyzer., Results: The concentrations of TC and LDL in individuals of TNFbeta+252GA genotype was significantly higher than that in TNFbeta+252AA genotype (t=-2.406, P=0.017; t=-2.516, P=0.012). The concentration of LDL in IL-10+3953CT genotype was significantly higher than that in IL-10+3953CC genotype (2.743-/+0.723 vs 2.502-/+0.699 mmol/L, t=-2.639, P=0.009). No significant differences were found in TG, TC, HDL, LDL and VLDL between the 3 genotypes (P>0.05)., Conclusion: The polymorphisms of proinflammatory cytokines are related to the serum lipoprotein level in these subjects. The T allele in IL-1beta+3953 and the G allele in TNFbeta+252 are positively correlated to dyslipidemia.

Objective: To investigate the feasibility of continuous intraspinal ceftazidime administration for treatment of purulent meningitis due to Achromobacter infection., Methods: A patient with established diagnosis of purulent meningitis due to Achromobacter infection was admitted, who failed to respond favorably to a 3-day ceftazidime treatment administered intravenously. Continuous intraspinal ceftazidime administration at the dose of 0.2 g/d was then attempted through a catheter placed in the cisterna magna in addition to intravenous ceftazidime for 3 days, which resulted in obvious relief of the symptoms. The catheter was subsequently withdrawn, and the patient received further treatment with additional intravenous ceftazidime for a week., Results: The symptoms of purulent meningitis was significantly improved after a 3-day continuous intraspinal ceftazidime administration, and the patient was eventually cured after completion of the treatment course. Intrathecal ceftazidime was also attempted previously but failed due to intolerance of pains in the legs. No relapse was observed in this case 3 months after the discharge., Conclusion: Continuous intraspinal ceftazidime administration can be effective and safe for treatment of purulent meningitis.

Objective: To investigate the pathological characteristics of heroin spongiform leukoencephalopathy (HSLE)., Methods: Cerebral tissue specimens were obtained from 15 patients with HSLE and the histological observations under optical and electron microscopes were carried out by HE, Bielschowsky's, and chromotrope 2R-brilliant green staining., Results: HSLE was characterized primarily by spongiform vacuolar degeneration of the cerebral white matter. Neurons in the gray matter, Purkinje and granular cells in the cerebella remain intact in all the cases. Numerous vacuoles, which merged to form larger cavities, appeared in the damaged white matter, and the axons survived in the deep white matter. The myelin sheath in the cerebellar white matter sustained more severe damages than those in the cerebral white matter. No vacuoles or lymphocyte infiltration occurred in the small peripheral vessels., Conclusion: HSLE is pathologically characterized by vacuolar degeneration due to primary damage of the myelin, and the spongiform vacuolar degeneration is closely associated with the severity of demyelination in the white matter.

Objective: To study the relationship between polymorphisms of interleukin 10 (IL10QX) promoter and serum levels of lipoprotein in the healthy Chinese Han population., Methods: PCR restriction fragment length polymorphism assay was used to detect the distribution of genotypes of IL10 -592,-819,-1082 in 200 healthy Chinese Han subjects. Serum levels of total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein (VLDL) in all subjects were measured to analyze the relationship with the polymorphisms of IL10 promoter., Results: Comparing with AA genotype, the group with GA genotype at IL10 promoter -1082 position had a significant elevation of serum HDL-C level [(1.514+/-0.501) mmol/L vs. (1.261+/-0.346) mmol/L, t=-2.225, P=0.028] and a lower serum TG level[(1.701+/-1.836) mmol/L vs. (0.981+/-0.314) mmol/L,Z=-2.096,P=0.036]. The TG, TC, HDL-C, LDL-C and VLDL levels did not show any statistically significant differences among different genotypes (CC, AA, CA) of the IL10 -592, as well as the genotypes (TT, TA, AA) ofIL10 -819 (P>0.05)., Conclusion: The results suggest that in the Chinese Han population, the polymorphism at position -1082 in the promoter region of IL10 gene may be associated with the serum HDL-C level and TG level.

Objective: To study the mechanisms of dystrophin gene deletion by cloning and sequencing the junction fragment of dystrophin gene with exons 3 to 5 deletion., Methods: PCR was performed to verify dystrophin gene exons 3 to 5 deletion in a patient with Duchenne muscular dystrophy. A PCR-based genome-walking method was used to localize the breakpoint in introns 2 and 5, and the deletion-junction fragment was directly amplified by PCR approach with forward and reverse primers annealing to a DNA sequence as close as possible to the breakpoint in the introns 2 and 5. The sequencing result of the deletion-junction fragment was compared with the normal intron sequences., Results: A sequence of 2113 bp containing the junction fragment was obtained. The 5' breakpoint was located in SINE/Alu element of intron 2, and the 3' breakpoint was located in the unique sequence near the sequence TTTAAA. The breakpoints were associated with a strong topoisomerase II cleavage site. A 26-bp fragment was inserted into the breakpoint and formed 3 duplications (GGCTTATATTTAA) of 13 bp around the deletion-junction fragment., Conclusion: Repeat sequence and strong topoisomerase II cleavage site around the breakpoint may predispose double-strand DNA breaks and recombination, which, in addition to the nonhomologous end-joining mechanism, may contribute as important factors to the gene deletion.

Objective: To study the mechanisms of dystrophin gene deletion, the junction fragment with exons 45-54 deletion were cloned and sequenced., Methods: A Duchenne muscular dystrophy (DMD) patient with exons 45-54 deletion has been substantiated by PCR amplification of the exons. Then we used a PCR-based genome-walking method for localizing the breakpoints in introns 44 and 54. At last, the deletion-junction fragment was directly amplified by PCR approach with forward and reverse primers annealing to a DNA sequence as close as possible to the breakpoints in introns 45 and 54. The sequencing result of the deletion-junction fragment was compared with the normal intronic sequences., Results: A total of 2716 bp sequence containing the junction fragment was obtained. The 5' breakpoint was located in LINE/L1 element of intron 44 and close to a matrix attachment region (MAR). The 3' breakpoint was located in the minor potential MAR with topoisomerase II cleavage sites around. Beside the 3' breakpoint there was a 6 bp palindromic sequence. A 4 bp microhomologous sequence (AGAG) was in the joint of the deletion-junction fragment., Conclusion: The nonhomologous recombination caused by L1 repeated element, topoisomerase II cleavage sites, MARs and the nonhomologous end joining of microhomologous sequence may be the important factors in this huge gene fragment deletion.

Aim: To observe the therapeutic effect of intrasplenic transplantation with embryonic hepatocytes on amelioration of hereditary copper accumulation in toxic milk (TX) mouse modeling Wilson disease., Methods: Donor hepatocytes were harvested from 14-d fetal liver of a pregnant homogeneous DL mouse. These cells were successively cultured, labeled with fluorescein dye Hoechst 33342 for 24 h, and sequentially infused into the spleen parenchyma of the recipient TX mice. No host immunosuppression measures were taken. Two and four weeks after transplantation, the recipients were killed for routine histologic investigation and immunohistochemistry study up to 4 wk after transplantation. The serum copper and ceruloplasmin concentrations of the recipient mice were determined by graphite furnace atomic absorption spectroscopy., Results: In the following 2nd and 4th wk after transplantation, the donor hepatocytes could be visualized in the livers of 47.3% recipients. The serum ceruloplasmin and copper concentrations increased by 1.6-fold after 2 wk and 2.0-fold times after 4 wk respectively, which ultimately rose from about 30% of the normal level to nearly 60% (P<0.01). The hepatic copper concentration decreased 7.2%, 4 wk after transplantation. Pathologic examination showed that there were many actively proliferative hepatocyte precursor cells with specific embryonic hepatocyte marker AFP migrated into hepatic sinusoids of the recipients. A large number of cells carrying hepatocytes marker and albumin were observed in the recipient spleen tissues., Conclusion: Embryonic hepatocytes are capable of differentiating into mature hepatocytes in vivo. After transplantation, the hereditary abnormalities of copper metabolism in TX mice could be corrected partially by intrasplenic transplantation of homogeneous embryonic hepatocytes.

Objective: To study the exons deletion mechanisms for dystrophin gene, the molecular characters of breakpoints of junction fragments for deletion-type Duchenne muscular dystrophy (DMD) patients with 46 and 51 exons deletion were compared and analyzed., Methods: Deletion-type DMD patients were detected by multiplex polymerase chain reaction(mPCR). The breakpoints of junction fragments with 46 and 51 exons deletions were cloned and sequenced respectively., Results: Analysis of sequences of deletion-junction fragment of exon 46 showed that the 5'breakpoint was located in AT-rich region of intron 45 and the 3' breakpoint was in medium reiteration repeats (MER1) sequence. There existed 2 bp(ta) junction homology between two breakages. No small insertion, small deletion or point mutation was located near the junction point. Similarly, analysis of sequences of deletion-junction fragment of exon 51 showed that the 5 breakpoint was located in transposon-like human elements (THE1) of intron 50 and the 3' breakpoint was in L2 sequence. There existed 3 bp(cta) junction homology between two breakages. No small insertion, small deletion or point mutation was located near the junction point. By analyzing the secondary structure of junction fragments with 46 and 51 exons deletions, it was demonstrated that all breakpoints of junction fragments were located at the non-matching regions of single-strand hairpin., Conclusion: By comparing the junction fragments with 46 or 51 exons deletion, it was found that all of breakpoints were located in repeat sequences and the repeat sequences formed the single-strand hairpin which could make the introns instable and result in exon deletion.

Objective: To investigate the association between the C311S polymorphism of paraoxonase 2 (PON2) gene and ischemic stroke in Chinese type 2 diabetes mellitus (T2DM) patients., Methods: A case-control study of 279 Chinese subjects (including 162 T2DM with or without ischemic stroke and 117 non-diabetic control) was performed. Genotype frequencies of C311S polymorphism were studied by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) analysis with DdeI digestion., Results: C311S polymorphism of PON2 gene was detected in Chinese with the C/S allele frequencies 0.145 and 0.855. The frequency distribution showed significant difference between Chinese and Asian Indian. Furthermore, the genotype distribution (SS, CS and CC) of the PON2 C311S gene polymorphism exhibited a significant difference between T2DM patients complicated with ischemic stroke and T2DM without ischemic stroke, the former had a significantly higher C allele frequency(P<0.05)., Conclusion: The above data indicate that the polymorphism at codon 311(Cys --> Ser)in the PON2 gene is associated with ischemic morbidity in Chinese T2DM patients and C allele might be a risk factor.

This study aimed to investigate the gene polymorphism of the C242T p22phox in the population of Han nationality in Guangdong Province by randomly selecting 122 unrelated healthy candidates examined by means of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). It was found that the C and T allele frequencies were 0.934 and 0.066, and CC and CT+TT genotype frequencies were 0.877 and 0.123, respectively, in the population of Han nationality in Guangdong Province, suggesting the presence of C242T p22phox gene polymorphism with significant racial differences.

To study the mechanism of Dystrophin gene deletion, we obtained the deletion junction fragment of exon 51 by inverse PCR and analyzed the sequence characteristic of breakpoints and deletion junction fragment. After the full sequence of intron 51 was finished, the rough site of breakpoint in intron 51 of a DMD patient with exon 51 deletion was detected by PCR with 9 pairs of primers spaced every 3-5 kb in intron 51. Then the junction fragment was amplified by nested inverse PCR. After sequencing the junction fragment, the 3' breakpoint and partial sequences of intron 50 were determined by comparing with the normal sequences in intron 51. The primer was designated to sequence intron 50 according to the sequence of junction fragment, and then the 5' breakpoint was determined. A total of 1,614 bp in intron 50 was sequenced. The 5' and 3' breakpoints were located in the THE-1 internal sequence (Transposon-like Human Element, THE) and L2 sequence respectively. There are 3 bp junctional homology and no errors near the junction point. This is the second report that the deletion breakpoint located directly in THE-1 sequence studied at the DNA level. We here firstly reported that there is a THE-1 sequence in intron 50. THE-1 and non-homologue end joining repair mechanism may be associated with the Dystrophin gene deletion.