Perfusion imaging by a flow-sensitive alternating inversion recovery (Fair) technique: Application to functional brain imaging

Perfusion is a crucial physiological parameter for tissue function. To obtain perfusion-weighted images and consequently to measure cerebral blood flow (CBF), a newly developed flow-sensitive alternating inversion recovery (FAIR) technique was used. Dependency of FAIR signal on inversion times (TI) was examined; signal is predominantly located in large vessels at short TI, whereas it is diffused into gray matter areas at longer TI. CBF of gray matter areas in the human brain is 71 ± 15 SD ml/100 g/min (n = 6). In fMRI studies, micro- and macrovessel inflow contributions can be obtained by adjusting TIs. Signal changes in large vessel areas including the scalp were seen during finger opposition at a TI of 0.4 s; however, these were not observed at a longer TI of 1.4 s. To compare with commonly used BOLD and slice selective inversion recovery techniques, FAIR and BOLD images were acquired at the same time during unilateral finger opposition. Generally, activation sites determined by three techniques are consistent. However, activation of some areas can be detected only by FAIR, not by BOLD, suggesting that the oxygen consumption increase couples with the CBF change completely. Relative and absolute CBF changes in the contralateral motor cortex are 53 ± 17% SD (n = 9) and 27 ± 11 SD ml/100 g/min (n = 9), respectively.     

大剂量地塞米松及SOD在实验性脑损伤中的治疗作用

大剂量地塞米松和ＳＯＤ是外伤性脑继发性损害药物治疗的新方案。本实验在豚鼠局灶性脑损伤模型上试用该两种药物，通过脑含水量、灶周伊文斯兰渗出、血ＣＫ、Ｃａ和ＬＤＨ含室及光镜和电镜病理检查等指标。     

国人脑内某些解剖结构定位研究与临床应用

本文通过对４５个正常成人脑标本进行三维连续２ｍｍ切片，对Ｆｏｒｅｌ－Ｈ，隔区等九个脑内重要结构的解剖坐标及毗邻关系进行观测，为立体定向手术提供解剖学依据。５５例临床实践证明手术疗效比较满意。     

Manic episode with psychotic symptoms induced by subthalamic nucleus stimulation in a patient with Parkinson's disease.

Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established therapy for Parkinson's disease (PD). A manic episode with psychotic symptoms induced by STN-DBS occurred in a previously psychiatrically healthy patient, focusing on the role of STN-DBS in influencing not only motor but also emotional behaviour.     

立体导向下脑肿瘤后装治疗及疗效观察

本文总结１５例经后装治疗后肿瘤疗效观察，认为要显示后装治疗特点和效果，应选择直径在３０ｍｍ左右，脑深部不宜外种切除肿瘤。另外，要合理制订放射治疗计划；施源管要与肿瘤主轴方位保持一致，这样病灶才可达到完全覆盖，发挥后装治疗作用。     

金尔伦治疗急性颅脑损伤的剂量效应研究

目的探讨金尔伦(盐酸纳洛酮)在治疗大鼠液压脑损伤后神经功能恢复和病理损害程度的剂量效应.方法将104只SD大鼠随机分为4组,伤后早期分别腹腔注射0.03 mg/Kg(小剂量组)、0.3 mg/Kg(中剂量组)、3 mg/Kg(大剂量组)金尔伦和等量生理盐水(对照组),连续7 d.结果中、大剂量组动物伤后脑神经功能恢复、脑水肿减轻程度及光、电镜检查显著优于对照组及小剂量组.结论伤后早期使用中剂量和大剂量金尔伦(盐酸纳洛酮)对大鼠液压颅脑损伤有明显的治疗效果.     

Long-term benefit to pallidal deep brain stimulation in a case of dystonia secondary to pantothenate kinase-associated neurodegeneration.

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN.     

Neurosteroid modulation of allopregnanolone and GABA effect on the GABA-A receptor

The neurosteroid allopregnanolone (ALLO) or 3α-OH-5α-pregnane-20-one interacts with the GABA type A receptor chloride ion channel complex and enhances the effect of GABA. Animal and human studies suggest that ALLO plays an important role in several disorders including premenstrual syndrome, anxiety, and memory impairment. In contrast to ALLO, steroids with a hydroxy group in the 3β position usually exert a reducing effect and have recently attracted interest due to their suggested role in counteracting the negative action of ALLO. In this study, five different 3β-steroids were tested for their ability to modulate GABA-mediated chloride ion uptake in the absence and presence of ALLO in rat brain microsacs preparations. In addition, the effects of the 3β-steroids and their interaction with ALLO were investigated by patch-clamp recordings of spontaneous inhibitory postsynaptic currents (sIPSCs) in rat hypothalamic neurons from the medial preoptic nucleus (MPN). All tested 3β-steroids reduced the ALLO-enhanced GABA response in cerebral cortex, in hippocampus and in MPN. In cerebellum, only one had this effect. However, in the absence of ALLO, two of the 3β-steroids potentiated GABA-evoked chloride ion uptake and prolonged the sIPSCs decay time, whereas the others had little or no effect. Therefore, it is possible that at least some 3β-steroids can act as positive GABA_A receptor modulators as well as negative modulators depending on whether or not ALLO is present. Finally, these results suggest that the 3β-steroids could be of interest as pharmacological agents that could counteract the negative effects of ALLO.     

Age-related changes in the turnover rates of D1-dopamine receptors in the retina and in distinct areas of the rat brain

The steady-state density and the turnover rates of D₁-dopamine receptors were investigated in the striatum, nucleus accumbens, substantia nigra, and retina of adult (3-month-old) and aged (23-month-old) rats. The turnover rates were measured by monitoring the repopulation kinetics of D₁-dopamine receptors labeled with [³H]-SCH 23390 after the irreversible inactivation induced by a single dose of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 mg/kg, s.c.). In all the neural tissues examined, the repopulation of D₁ dopamine receptors could be adequately described by a theoretical model that assumes a constant rate of receptor production (i.e. zero order) and a rate of degradation that is dependent on the receptor density at any time (i.e. first order). The results obtained indicate that the reduction in the density of D₁-dopamine receptors in the striatum, nucleus accumbens and substantia nigra of aged rats is the result of a larger decrease in the receptor production rate (−44 to −60%) than in the receptor degradation rate (−21 to −46%). By contrast, the production rate of D₁-dopamine receptors in the retina of aged rats remains unchanged, whilst the degradation rate is reduced by 25%. This results in an age-related increase in the density of D₁-dopamine receptors in the rat retina.