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681.
AIM: To investigate whether pretreatment with 3-n-butylphthalide (NBP) ameliorates blood brain barrier (BBB) dysfunction in a rat model of focal cerebral ischemia-reperfusion injury (CIRI). METHODS: Male SD rats (n=120, 24 rats in each group) were randomly divided into sham operation group (sham group), model group (IR group), low dose group of NBP pretreatment (NBP I group), medium dose group of NBP pretreatment (NBP II group) and high dose group of NBP pretreatment (NBP III group). The model of CIRI was established by a suture method. After ischemia for 2 h and reperfusion for 24 h, the contents of water and Evans blue (EB) were detected. The pathological changes of the BBB ultrastructure were observed under transmission electron microscope. The protein level of matrix metalloproteinases 9 (MMP-9) was measured by immunohistochemical technique. The mRNA expression of MMP-9 was determined by real-time PCR. RESULTS: After CIRI, the content of water and EB was progressively increased, the BBB was damaged seriously, and the expression of MMP-9 was significantly up-regulated compared with sham group (all P<0.01). Pretreatment with NBP significantly decreased the contents of water and EB, relieved morphological damage of the BBB, and reduced the expression of MMP-9 obviously (all P<0.01). Compared with NBP I group, the changes in NBP II and III group were remarkable (P<0.05), but the difference between NBP II group and NBP III group was not obvious (P>0.05). CONCLUSION: Pretreatment of 3-n-butylphthalide has preventive effect against cerebral ischemia reperfusion injury in the rats, which may be related to decrease the expression of MMP-9 and reduce the permeability of blood brain barrier.  相似文献   
682.
BackgroundThe blood‐brain barrier (BBB), which separates the intravascular and neuropil compartments, characterizes the vascular bed of the brain and is essential for its proper function. Recent advances in imaging techniques have driven the development of methods for quantitative assessment of BBB permeability.Hypothesis/ObjectivesPermeability of the BBB can be assessed quantitatively in dogs with meningoencephalitis of unknown origin (MUO) and its status is associated with the occurrence of seizures.AnimalsForty dogs with MUO and 12 dogs without MUO.MethodsRetrospective, prospective cohort study. Both dynamic contrast enhancement (DCE) and subtraction enhancement analysis (SEA) methods were used to evaluate of BBB permeability in affected (DCE, n = 8; SEA, n = 32) and control dogs (DCE, n = 6; SEA, n = 6). Association between BBB dysfunction (BBBD) score and clinical characteristics was examined. In brain regions where BBBD was identified by DCE or SEA magnetic resonance imaging (MRI) analysis, immunofluorescent staining for albumin, glial fibrillary acidic protein, ionized calcium binding adaptor molecule, and phosphorylated mothers against decapentaplegic homolog 2 were performed to detect albumin extravasation, reactive astrocytes, activated microglia, and transforming growth factor beta signaling, respectively.ResultsDogs with BBBD had significantly higher seizure prevalence (72% vs 19%; P = .01) when compared to MUO dogs with no BBBD. The addition of SEA to routine MRI evaluation increased the identification rate of brain pathology in dogs with MUO from 50% to 72%.Conclusions and Clinical ImportanceImaging‐based assessment of BBB integrity has the potential to predict risk of seizures in dogs with MUO.  相似文献   
683.
目的 探讨益气活血温心汤联合西药对慢性心力衰竭(chronic heart failure,CHF)患者心功能、血浆脑钠肽(brain natriuretic peptide,BNP)、超敏C-反应蛋白(hypersensitive c-reactive protein,hs-CRP)等的影响。方法 将2017年10月至2018年10月本院门诊部收治的92例CHF患者随机分为观察组和对照组,每组46例。对照组采用西药常规治疗,观察组在对照组的基础上采用益气活血温心汤治疗。观察治疗后两组CHF患者的临床疗效,对比治疗前后两组CHF患者心功能[左心室射血分数(left ventricular ejection fractions,LVEF)及左心室舒张末期内径(left ventricular end diastolic diameter,LVEDD)]、血浆BNP浓度、hs-CRP水平及6 min步行距离。结果 (1)治疗后观察组患者的总有效率高于对照组,差异有统计学意义(P<0.05);(2)治疗后,两组患者的6 min步行距离较治疗前升高,血浆BNP浓度、hs-CRP水平较治疗前比较有所下降,差异均有统计学意义(P<0.05),且观察组的6 min步行距离高于对照组(P<0.05),血浆BNP浓度、hs-CRP水平低于对照组(P<0.05);(3)治疗后,两组患者的LVEF较治疗前升高,LVEDD较治疗前下降,差异均有统计学意义(P<0.05),且观察组的LVEF高于对照组,LVEDD低于对照组(P<0.05)。结论 益气活血温心汤联合西药治疗CHF患者疗效明显,可通过提高6 min步行距离、LVEF并且降低血浆BNP浓度、hs-CRP水平、LVEDD来实现,且优于单纯西药治疗。  相似文献   
684.
李谣  杨智茹  程景颢  李杰  宁先会  王涛  张凯  暨杰  张国松  尹绍武 《水产学报》2023,34(1):019611-1-019611-13
为了解长吻鮠脑组织应对低氧胁迫的调控机制,实验运用酶活性测定、H.E染色、qRT-PCR和TUNEL检测等方法,分析比较了低氧胁迫[(0.8±0.1) mg/L] 0、2、4、6 h(标示为H0、H2、H4和H6)和恢复[(7.3±0.5) mg/L]2、4、6 h (标示为R2、R4和R6)下长吻鮠脑组织低氧应答基因、生理生化指标和食欲基因的变化。结果显示,在低氧胁迫和恢复下,长吻鮠脑组织氧传感蛋白相关基因(HIFsPHDsVhl)表达量整体呈现出先上升后下降趋势;呼吸代谢酶(HK、PK和LDH)活性在H0时显著升高,SDH和MDH活性在H6时显著降低,恢复溶解氧后,代谢模式由无氧呼吸逐渐转变为有氧呼吸;抗氧化酶(GSH-Px、CAT和SOD)和应激指标(MDA和LPO)在低氧2 h后逐渐升高,恢复溶解氧后氧化应激现象仍然存在。观察脑组织形态发现,在低氧胁迫下长吻鮠脑组织出现了神经细胞肿胀、空泡等受损现象,恢复溶解氧6 h后脑组织受损并未得到有效改善。随着低氧时间延长,脑组织细胞凋亡程度不断增加,凋亡相关基因(BaxCaspase-3和p53)表达量显著升高,而Bcl-2基因表达量降低,恢复溶解氧后较对照组仍有显著差异。另外,在低氧胁迫0 h和2 h时,长吻鮠摄食率分别下降54%和98%,检测到低氧胁迫能显著抑制促食基因(NPY)和诱导抑食基因(PYY、CCKNUCB2)表达。研究表明,低氧胁迫和恢复对长吻鮠脑组织氧传感蛋白、呼吸代谢、氧化应激、结构形态、细胞凋亡以及食欲等指标均具有显著影响。本研究结果为阐明低氧胁迫和恢复下长吻鮠脑组织分子调控机制提供一定的理论依据,对今后开展该鱼集约化健康养殖和耐低氧新品种选育工作具有指导意义。  相似文献   
685.
AIM: To study the effect of moderate hypothermia on immature rats with hypoxic-ischimic brain damage (HIBD). METHODS: The rats with HIBD were divided into normothermic recovered group (IN) and moderate-hypothermic recovered group (IH). Sham-operated rat pups were normothermic control group (NC) and moderate-hypothermic control group (HC). 0, 2, 6, 24, 48, 72 h after the end of hypoxic-ischemic (HI) insult, the brain was homogenized for measuring glucose and ATP, brain mitochondria was extracted for SDH activity, complex II activity and the capacity of ATP synthesization. RESULTS: In IN group, the brain glucose was significantly lower at 0 h, and recovered as normal at 2 h. The brain ATP and brain-mitochondrial SDH activities were firstly decreased at 2 h, 6 h and then recovered gradually, it was at it's peak value at 72 h. Brain-mitochondrial complex II activity and the capacity of ATP synthesis were recovered at 2 h, but they decreased again at 6 h and came to normal level at 72 h. In moderate-hypothermic group, all the indexes were significantly higher at all the time point than that in IN groups. CONCLUSION: Moderate hypothermia inhibits the decrease in the mitochondrial SDH activity, mitochondrial complex II activity and the capacity of ATP synthesis, increases the brain ATP concentration, improves the energy metabolism, and then protects the brain tissue.  相似文献   
686.
1. Acrylamide (ACR) is a potent neurotoxicant, although information on its toxic influence on the developing neural system is still limited. The effects of in-ovo-injected ACR on the antioxidant system activity in the brain of newly hatched chickens was examined. This model eliminated the mother’s contribution to embryonic development. It was also recognised as an adequate model for animal embryonic development.

2. ACR was injected on d 4 of embryogenesis – in doses of 1.25 and 2.50 mg/egg (n = 40 eggs/group/120 eggs). The doses corresponded well with ACR doses used in other animal studies and their concentrations in certain animal feeds.

3. Mortality and incidences of malformations were not found to increase significantly. Significant depletion of glutathione was detected in the cerebellum, cerebrum and medulla oblongata of specimens exposed to the highest doses of ACR. Enzymatic activity was affected by the highest ACR doses. Glutathione peroxidase (GPx) activity increased significantly in the cerebrum, medulla oblongata and the hypothalamus. Superoxide dismutase (SOD) activity increased significantly in hypothalamus and decreased in cerebellum and cerebrum. A significant depletion of catalase (CAT) activity was detected in cerebellum. In the hypothalamus, the increased SOD/GPx and SOD/CAT ratios suggest the risk of H2O2.

4. It was concluded that ACR significantly influences the antioxidative defence in the chicken brain at doses of 1.25 and 2.50 mg/egg.  相似文献   

687.
针对重组子中100bp左右的小插入片段与载体不能同时在普通琼脂糖胶上呈现而无法用内切酶图谱鉴定此类重组子的问题,提出了小插入片间接内切酶图谱,并用普通琼脂糖凝胶电泳研究分析了此类图谱。  相似文献   
688.
李谣  杨智茹  程景颢  李杰  宁先会  王涛  张凯  暨杰  张国松  尹绍武 《水产学报》2023,47(1):019611-019611
为了解长吻鮠脑组织应对低氧胁迫的调控机制,实验运用酶活性测定、H.E染色、qRT-PCR和TUNEL检测等方法,分析比较了低氧胁迫[(0.8±0.1) mg/L] 0、2、4、6 h(标示为H0、H2、H4和H6)和恢复[(7.3±0.5) mg/L]2、4、6 h (标示为R2、R4和R6)下长吻鮠脑组织低氧应答基因、生理生化指标和食欲基因的变化。结果显示,在低氧胁迫和恢复下,长吻鮠脑组织氧传感蛋白相关基因(HIFs、PHDs和Vhl)表达量整体呈现出先上升后下降趋势;呼吸代谢酶(HK、PK和LDH)活性在H0时显著升高,SDH和MDH活性在H6时显著降低,恢复溶解氧后,代谢模式由无氧呼吸逐渐转变为有氧呼吸;抗氧化酶(GSH-Px、CAT和SOD)和应激指标(MDA和LPO)在低氧2 h后逐渐升高,恢复溶解氧后氧化应激现象仍然存在。观察脑组织形态发现,在低氧胁迫下长吻鮠脑组织出现了神经细胞肿胀、空泡等受损现象,恢复溶解氧6 h后脑组织受损并未得到有效改善。随着低氧时间延长,脑组织细胞凋亡程度不断增加,凋亡相关基因(Bax、Caspase-3和p53)表达量显著升高,而Bcl-2基因表...  相似文献   
689.
为切实做好大豆—玉米带状复合种植区鼠害防控工作,减少粮食损失,本文结合贵州省鼠害防治研究成果,总结了大豆—玉米带状复合种植区鼠害防控技术,提出了下步鼠害防控工作建议,旨在进一步普及鼠害防控技术,有效控制鼠类危害,确保粮食生产安全。  相似文献   
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