ABSTRACT
Objective To explore the value of multimodal magnetic resonance myocardial perfusion imaging (MR-MPI)in detecting myocardial viability of coronary heart disease.Methods 52 patients suspected or diagnosed coronary heart disease confirmed with SPECT myocardial perfusion and had MR-MPI examination were collected.MR-MPI protocol included double inversion T2WI fat suppressed imaging,diffusion weighted imaging(DWI),resting perfusion and dipyridamole myocardial perfusion.Results In 52 patients,the sensitivity,specificity,positive predictive value and negative predictive value of MR-MPI were 89.13%,66.67%,95.35% and 44.44% respectively.Conclusion MR-MPI can effectively detect myocardial viability in coronary heart disease.MR-MPI exhibits high clinical value for qualitative evaluation of degree of the myocardial ischemic coronary heart disease.
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Objective To explore the effect of neural stem cells (NSCs) transplantation on neurogenesis in an alzheimer' disease mouse model and its related mechanism.Methods A total of 16 12-month old aPP/PS1 double transgenic aD mice were randomly divided into two groups:NSC group (receiving NSCs transplantation in the bilateral hippocampi,n=8) and PBS group as the negative control group (receiving an equal quantity of 0.01M/L phosphate buffer saline,n=8).another 8 wild type mice without any treatment were selected as the positive control group (Wt group).at five weeks after transplantation,the expressions of doublecortin (DCX) and nestin in the hippocampal dentate gyrus (DG) and subgranular zone (SGZ) were analyzed by immunofluorescence staining,the number of positive cells in these regions were counted by confocal microscopy,and Morris water maze (MWM) test was used to assess cognitive function in all mice.Results NSC group showed the enhanced spatial learning and memory ability in Morris water maze (MWM) as compared to PBS group,but it was still lower than that in Wt mice (both P＜0.05).Immunofluorescence staining showed NSCs induced the increased positive cells expressing DCX and nestin in the NSC group as compared with PBS group (F＝85.400 and 55.687,both P＜0.001).However,the number of DCX positive cells was still lower in NSC group than in Wt group (P＜0.05).There was no significant difference in the number of Nestin-positive cells between the NSC group and the Wt group (P＞ 0.05).Conclusions NSCs transplantation can promote endogenous neurogenesis via the increased expression of DCX-and Nestin positive cells in the hippocampal DG/SGZ in aD mice,which improves the cognitive abilities in aD mice in some extent.
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Objective To observe the effect of silencing P2X7 receptor (P2X7R) by RNA interference on microglial releasing interleukin 1β (IL-1β),tumor necrosis factor-α (TNF-α) and nitric oxide (NO).Methods The small interfering RNA (siRNA) targeting P2X7R gene was observed.The primary microglial cells activated by amyloid-β (Aβ-42) were infected with the lipofectaminesiRNA.The groups were designated as Aβ-1-42,Aβ1-42/siNC,Aβ1-42/siP2X7R and blank control groups according to the different stimulus.After RNA interference for 48 hours,the microglial cells were collected.The survival rate of microglia was detected by CCK-8.The levels of P2X7R mRNA and protein were detected by Real-time PCR and Western blotting respectively.The microglial morphology and the P2X7R immune response were observed by immunocytochemistry staining.Then levels of IL-1β,TNF-α and NO in the supernatantwere measured.Results The Aβ1-42 and siRNA had no effects on the survival rate of microglia.After RNA interference silencing P2X7R,the expression levels of P2X7R mRNA and protein in Aβ1-42/siP2X7R group were decreased significantly,and in this group,the microglial activity and P2X7R immune response were all reduced.In Aβ1-42,Aβ1-42/siNC,Aβ1-42 /siP2X7R and blank control groups,the supernatant levels of IL-1β were (52.54±3.21) μg L,(54.94±2.54) μg/L,(28.70±3.58) μg/L,(24.55±4.34) μg/L,respectively and the supernatant levels of TNF-α were (64.40±4.80) μg/L,(60.94±1.63) μg/L,(25.69±3.13) μg/l,(19.21±1.97)μg/L,respectively.As compared with Aβ1-42 and Aβ-42/siNC groups,the levels of IL 1β and TNF-α in Aβ1-42 /siP2X7R group was decreased significantly (P＜ 0.05),and IL-1β level had no significant difference between Aβ1-42/siP2X7R and blank control groups.The same result was observed in the level of NOin the supernatant.The levels of NO were (1.33±0.19) μmol/L,(4.49±0.28) μmol/L,(4.78±0.33) μmol/L and (1.07±0.36) μmol/L in Aβ1-42/siP2X7R,Aβ1-42,Aβ1-42 /siNC and blank control groups respectively.Conclusions The silencing expression of P2X7 R by RNA interference effectively decreases the levels of IL-1β,TNF-α and NO released by microglia.P2X7 R can be used as an effective therapeutic target for RNA interference treatment of Alzheimer's disease.