Nonlinear coupling between cerebral blood flow,oxygen consumption,and ATP production in human visual cortex

The purpose of this study was to investigate activation-induced hypermetabolism and hyperemia by using a multifrequency (4, 8, and 16 Hz) reversing-checkerboard visual stimulation paradigm. Specifically, we sought to (i) quantify the relative contributions of the oxidative and nonoxidative metabolic pathways in meeting the increased energy demands [i.e., ATP production (J_ATP)] of task-induced neuronal activation and (ii) determine whether task-induced cerebral blood flow (CBF) augmentation was driven by oxidative or nonoxidative metabolic pathways. Focal increases in CBF, cerebral metabolic rate of oxygen (CMRO₂; i.e., index of aerobic metabolism), and lactate production (J_Lac; i.e., index of anaerobic metabolism) were measured by using physiologically quantitative MRI and spectroscopy methods. Task-induced increases in J_ATP were small (12.2–16.7%) at all stimulation frequencies and were generated by aerobic metabolism (approximately 98%), with %ΔJ_ATP being linearly correlated with the percentage change in CMRO₂ (r = 1.00, P < 0.001). In contrast, task-induced increases in CBF were large (51.7–65.1%) and negatively correlated with the percentage change in CMRO₂ (r = −0.64, P = 0.024), but positively correlated with %ΔJ_Lac (r = 0.91, P < 0.001). These results indicate that (i) the energy demand of task-induced brain activation is small (approximately 15%) relative to the hyperemic response (approximately 60%), (ii) this energy demand is met through oxidative metabolism, and (iii) the CBF response is mediated by factors other than oxygen demand.     

头面部望诊积分与脑梗死患病率的相关性研究

目的探索头面部望诊在预测及诊断脑梗死中的价值。方法。。200例头面部望诊有异常的患者,根据其异常的轻重程度制定相应量化积分值,并行头颅磁共振成像（MRI）检查。发现有脑梗死者视为观察终点,记录为阳性。头颅MRI检查结果阴性者,追踪其6个月～18个月的病情变化和MRI检查结果,再次计算其量化积分值,进行统计分析,探讨不同积分值与脑梗死患病率的相关性,观察不同观察期脑梗死患病率的变化。结果积分阶梯I级～V级不同积分值与脑梗死患病率之间相关系数r=0．971,P=0．006,P〈0．01,二者显著正相关。随着望诊积分值的增加,脑梗死患病率显著增加。0～18个月不同观察期脑梗死例数与脑梗死患病率之间相关系数r=1．000,P=0．000,P〈0．001,二者显著正相关。随着时间的延长,脑梗死患病率显著增加。结论头面部望诊积分与脑梗死患病率呈显著正相关。     

心脑血管疾病患者脂蛋白(a)与ApoA_1、B的关系

测定150例急性脑血管病（其中脑出血51例．多发性脑梗塞56例，腔隙性梗塞43例），冠心病42例和高血压63例患者血清脂蛋白（a）及其血脂（AplA1、B、HDLc、TC和TG）含量。结果表明：多发性脑梗塞、脑出血和冠心病患者脂蛋白（a）水平与正常对照组比较明显升高（P＜0．01），其变化与其他血脂成分无相关性，支持Lp（a）为心脑血管疾病的独立危险因素。腔隙性梗塞和高血压Lp（a）升高不明显，脑出血患者血清ApoB和TC水平明显低于多发性脑梗塞（P＜0.01）。     

血液流变学指标对动脉硬化和脑梗死发生的预测分析

目的　探讨血液流变学指标的变化 ,预防和减少动脉硬化及脑梗死的发生和发展 ,以指导临床治疗。方法　选取 2 4 6例门诊患者的血液流变学结果加以分析 ,分为脑梗死组与脑动脉硬化组及有临床症状组 3组 ,并选择 73例同年龄健康人做对照。结果　各病例组的血液流变学指标均比对照组明显增高 ,差异有显著性意义 ;同时有 3组患者在全血黏度的高切变率和中切变率、血浆黏度、红细胞聚集指数和血小板聚集率上差异有显著性意义。结论　血液流变学的异常出现在疾病发生之前 ,故定期监测血液流变学指标可预防动脉硬化和脑梗死的发生 ,同时还对治疗有指导意义     

The combined effects of hypertension,hemodilution, and osmotherapy on the metabolic sequelae of acute experimental cerebral ischemia

The effects of induced hypertension, hemodilution, and osmotherapy (mannitol) have been assessed singly and in combination on the metabolic sequelae 2 hr after middle cerebral artery (MCA) occlusion in the anesthetized rat. All regimes that included hypertension and monotherapy with mannitol significantly reduced the rise in hemispheric lactate produced by vessel occlusion. No treatment caused increased cerebral edema, and mannitol produced a slight reduction in the hemisphere water content. The significance of the results is discussed.     

心电图在急性脑梗死与脑出血临床检测与预后分析中的应用

目的：探讨心电图在急性脑梗死与脑出血临床检测与预后分析中的应用。方法对我院收治的105例患有急性脑梗死和脑出血的急性脑血管疾病患者的临床资料进行回顾性分析,所有患者经磁共振成像和头颅 CT 确诊,并同心电图检查结果进行对比分析。结果105例患者中出现心电图异常者69例,异常率为65．7％。其中,急性脑梗死患者57例,心电图异常36例（63．2％）;脑出血患者48例,心电图异常33例（68．8％）。患者的心电图异常主要表现为 T 波改变、ST-T 改变、心律失常、QT 间期延长、明显 U 波、异常 Q 波等,且与病变部位有关。丘脑发生病变的患者心电图异常率明显高于其他部位发生病变的患者。在36例心电图正常患者中,死亡2例（5．6％）;在69例心电图异常患者中,死亡9例（13．0％）,差异有统计学意义（P ＜0．05）。无意识障碍患者68例,心电图异常33例（48．5％）;存在意识障碍患者37例,心电图异常31例（83．8％）,差异也有统计学意义（P ＜0．05）。结论急性脑梗死和脑出血患者具有较高的心电图异常率,并且异常类型较多。心电图变化可作为初步判断病情和预后的指标。     

Regional depletion of adenosine triphosphate,phosphocreatine, and glucose in ischemic hippocampus

The selective vulnerability of pyramidal neurons in the CA1 hippocampal region in ischemic rat brain may be preceded by regional alterations of energy metabolism during early reperfusion. We measured ATP, phosphocreatine (PCr), and glucose in paramedian and lateral CA1 and in an area showing little postischemic cell loss, CA2. ATP levels in paramedian CA1 were depressed immediately after 30 min of ischemia (P 0.02) and remained abnormal after 2 hr of reperfusion (P 0.05). PCr was reduced substantially in both subdivisions of CA1 immediately after ischemia (P 0.04) but returned to normal levels after 2 hr. Glucose levels were depressed in paramedian CA1 and CA2 after ischemia (P 0.02) but corrected with reperfusion. We determined P, the sum of ATP and PCr, in separate experiments investigating regional differences in consumption of high-energy phosphate metabolites during complete ischemia. The P levels of rats subjected to 30 min of reversible ischemia followed by 2 hr of reperfusion showed a different pattern of regional differences from those seen in sham-ischemic animals (P 0.01), indicating a persistent depression of metabolic rate in CA1 during reperfusion. We conclude that regional depletion of high-energy phosphates and alteration of metabolic rate may contribute to the selective vulnerability of the CA1 region during brain ischemia.     

载脂蛋白E基因多态性与血脂代谢和脑梗死的关系

载脂蛋白E（ApoE）在血浆脂质代谢中起重要作用。人apoE基因具有多态性，3种等位基因（ε2、ε3和ε4）编码3种异构体（E2、E3和E4）。与ε3等位基因相比，ε2等位基因与较低的ε4等位基因和较高的血浆总胆固醇、低密度脂蛋白胆固醇相关。     

大脑中动脉闭塞部位和机制对脑梗死病灶分布模式和NIHSS评分的影响

目的:分析大脑中动脉(MCA)闭塞部位和机制对脑梗死病灶分布模式和国立卫生研究院卒中量表(NIHSS)评分的独立和综合影响,探讨可能的相关机制及其对溶栓病例选择的潜在价值.方法:共纳入66例MCA闭塞所致新发脑梗死患者.闭塞部位分为MCA起始处(Ⅰ型)、主干远端(Ⅱ型)和分支(Ⅲ型),MCA闭塞机制分为栓塞性和血栓性闭塞,脑梗死病灶分布模式根据弥散加权成像(DWI)确定;NIHSS评分于发病24 h内完成.分析MCA闭塞部位和机制对脑梗死病灶分布模式和NIHSS评分的独立和综合影响.结果:MCA起始部闭塞和主干远端栓塞性闭塞患者脑梗死累及范围较大、NIHSS评分较高.与单因素分析相比,综合分析闭塞部位和机制可对MCA闭塞脑梗死患者进行更细致的分层.结论:综合分析MCA闭塞的部位和机制,可对MCA闭塞脑梗死患者进行很好的分层,可能有助于溶栓治疗病例的选择.     

缺血性脑血管病患者血脂、凝血及纤溶指标的变化

目的　观察缺血性脑血管病 (ICVD)患者血脂、凝血及纤溶指标的变化。方法　对缺血性脑血管病 113例 [包括脑梗死 (CI)急性期 2 5例 ,恢复期 30例 ;短暂性脑缺血发作 (TIA) 5 8例 ]和正常对照组 77名进行血脂、血浆组织型纤溶酶原激活物 (t PA)、纤溶酶原激活物抑制物 (PAI)和D 二聚体浓度进行测定。结果　CI组甘油三酯 (TG)、总胆固醇 (TC)、载脂蛋白B10 0 (ApoB10 0 )、氧化型低密度脂蛋白 (ox LDL)水平显著高于对照组 ;CI急性期、恢复期和TIA组PAI高于对照组 ,而t PA活性均低于对照组 ;TIA伴有梗死灶者血浆D 二聚体和PAI含量明显高于无梗死灶者 ,t PA含量低于无梗死灶者。结论　ICVD患者不仅存在血脂代谢紊乱 ,且体内凝血活性增强 ,纤溶功能下降。     

老年高血压并发脑梗死患者凝血、抗凝、纤溶系统功能改变及意义

目的分析老年高血压并发脑梗死患者凝血、抗凝、纤溶系统分子标志物指标的变化及意义，为临床早期诊断治疗提供客观依据。方法检测100例老年高血压患者、100例老年高血压合并脑梗死患者及100例健康老年对照者血管性血友病因子抗原（vWF：Ag）、血小板α-颗粒膜蛋白-140（GMP-140）、纤维蛋白原（FIB）的含量及抗凝血酶（AT）、蛋白S（PS）、蛋白C（PC）、组织型纤溶酶原激活剂（t-PA）、纤溶酶原激活剂抑制物-1（PAI-1）的活性，并进行分析与评价。结果与对照组相比，老年高血压患者、老年高血压合并脑梗死患者血浆vWF：Ag、GMP-140、FIB含量、PAI-1活性均明显升高，而AT、PS、PC、t-PA活性明显降低，差异具有统计学意义（P〈0．01）。结论老年高血压患者存在明显的凝血、抗凝及纤溶功能失衡，这与其病情进展及脑梗死的发生密切相关，早期防治具有重要的临床意义。     

Stroke Registration in Göteborg,Sweden, 1971-75

ABSTRACT Strokes occurring in persons 15–65 years of age (population 300 000) have been registered since 1970 in Göteborg, Sweden. From 1971 to 1974, 640 patients were registered and followed for at least one year. Coexisting cardio-cerebrovascular diseases were more frequent in the stroke patients than in random samples of the population of Göteborg of similar ages for each sex. At three weeks the degree of neurological deficit and type of stroke were decisive for prognosis, while the presence of cardio-cerebrovascular diseases influenced fatality rates negatively at one year.     

Morphine-Induced Changes of Adenylate and Guanylate Cyclase in Locus Ceruleus,Periaqueductal Gray,and Substantia Nigra in Rats

Objectives: To observe the changes of adenylate cyclase (AC) and guanylate cyclase (GC) in the cerebral regions including the locus ceruleus, periaqueductal gray, and substantia nigra in rats that were physiologically dependent on morphine. We also investigated the relationship of enzymatic changes in these cerebral regions to the mechanism of morphine dependence. Methods: A morphine-dependent rat model was established and withdrawal symptoms evaluated. Enzyme histochemistry was used to detect the variations of AC and GC in cerebral regions. Results: Compared to controls, AC and GC significantly increased in morphine-dependent groups. Comparisons of four different morphine-dependent groups also showed AC and GC significantly differed at weeks 1, 2, 4, and 8. Conclusions: Results found that the content of AC and GC increased in these cerebral regions in rats that demonstrated morphine dependence and appeared to be closely linked to increases in AC and GC activity.     

Clinical,neuroimaging, and behavioural risk factors for neurocognitive impairment in Chinese patients with haemophilia: A multicentre study

Background

Few studies have evaluated the impact of subclinical microstructural changes and psychosocial factors on cognitive function in patients with haemophilia.

Objectives

To determine the prevalence and characteristics of cognitive impairment in patients with haemophilia, and identify associated risk factors.

Methods

We recruited haemophilia A or B patients who were aged ≥10 years old from three public hospitals in Hong Kong. A neurocognitive battery was administered to evaluate their attention, memory, processing speed and cognitive flexibility performances. They also underwent magnetic resonance imaging to identify cerebral microbleeds. Validated self-reported questionnaires were administered to assess their mental health status and adherence to prophylactic treatment. General linear modelling was used to investigate the association of neurocognitive outcomes with risks factors, adjusting for age and education attainment.

Results

Forty-two patients were recruited (median age 32.0 years; 78.6% haemophilia A; 80.9% moderate-to-severe disease). Six patients (14.3%) had developed cerebral microbleeds. A subgroup of patients demonstrated impairments in cognitive flexibility (30.9%) and motor processing speed (26.2%). Hemarthrosis in the previous year was associated with worse attention (Estimate = 7.62, 95% CI: 1.92–15.33; p = .049) and cognitive flexibility (Estimate = 8.64, 95% CI: 2.52–13.29; p = .043). Depressive (Estimate = 0.22, 95% CI: 0.10–0.55; p = .023) and anxiety (Estimate = 0.26, 95% CI: 0.19–0.41; p = .0069) symptoms were associated with inattentiveness. Among patients receiving prophylactic treatment (71.4%), medication adherence was positively correlated with cognitive flexibility (p = .037).

Conclusion

A substantial proportion of patients with haemophilia demonstrated cognitive impairment, particularly higher-order thinking skills. Screening for cognitive deficits should be incorporated into routine care. Future studies should evaluate the association of neurocognitive outcomes with occupational/vocational outcomes.