~(18)氟标记脱氧葡萄糖正电子发射断层脑显像对癫痫患者致痫灶的定位和手术疗效的预测价值

目的　探讨18氟标记脱氧葡萄糖 (18F FDG)正电子发射断层 (PET)脑显像皮质代谢改变与癫痫患者致痫灶的关系 ,及其对手术方式选择和疗效预测的价值。方法　经手术治疗的 72例癫痫患者 (男 49例 ,女 2 3例 ,平均年龄 2 4岁 )术前行18F FDGPET脑显像并与同期磁共振 (MRI)、视频脑电图 (VEEG)结果进行比较 ,全部进行了疗效随访 (3～ 2 4个月 ,平均 15个月 ) ,其中 2 0例术后复查了18F FDGPET脑显像。结果　 72例患者术前PET显像均有皮质代谢改变 ,1例表现发作期高代谢 ,71例表现发作间期低代谢。18F FDG代谢改变检出率高于MRI,其定位定侧准确性高于VEEG ,但多发低代谢灶不一定全是致痫灶。术后FDG显像有助于判断低代谢灶性质。皮质低代谢灶合并同侧丘脑和 /或对侧小脑代谢减低 ,术前术后显像对比表明系功能性变化。术前FDGPET图像分型与手术方式和术后疗效相关。结论　手术前后FDGPET图像对比有助于评价代谢改变与癫痫灶的关系 ,代谢改变图型可帮助临床医生选择手术方式和预测疗效     

利用磁共振定量测定海马结构体积

目的：应用磁共振（ＭＲＩ）测定颞叶癫痫（ＴＬＥ）患者,非ＴＬＥ患者及正常人的海马结构（ＨＦ）体积。讨论该方法在确定ＴＬＥ致痫灶中的价值。方法：用ＭＲＩ对１３例ＴＬＥ患者,１７例非ＴＬＥ患者及３７例正常人作为脑干长轴平行的倾斜冠状位扫描,ＳＥ序列Ｔ１加权像,测量ＨＦ的体积。采用正常人ＨＦ体积的正常范围及左右两侧ＨＦ体积的差值的正常范围对ＴＬＥ患者可能存在的海马硬化进行定位定侧。结果：正常人ＨＦ的体积范围：右侧为１．９５～３．６８ｃｍ＾３,左侧为１．９３～３．６１ｃｍ＾３。ＴＬＥ组有７例患者的ＨＦ体积缩小,其中２例为双侧萎缩,而非ＴＬＥ组无一例ＨＦ体积缩小。结论：利用ＭＲＩ定量测定ＨＦ技术对ＴＬＥ患者可能存在的海马萎缩（ＨＡ）的定位定侧有较高的敏感性,比目测读片敏感,能提高ＴＬＥ患者ＨＡ的检出率。     

癫痫大鼠脑组织内免疫反应特点研究

目的研究脑“免疫特免性”与癫痫发病的关系。方法用免疫细胞化学法观察IgG免疫反应阳性(IgG-IR)细胞在两种不同处理程序的正常成年、癫痫及尼莫地平作用下癫痫大鼠脑组织内分布情况。结果灌注大鼠,除癫痫组个别脑片散在弱IgG-IR细胞外,其余均阴性;未灌注大鼠,各组脑片均散布IgG-IR细胞;癫痫大鼠脑组织IgG-IR细胞分布较正常组增多(p<0.01);尼莫地平作用下癫痫大鼠脑组织内IgG-IR细胞分布与正常组比较无显著差异。结论脑“免疫特免性”在癫痫发病中具有一定意义。     

癫痫患者P50听觉诱发电位的研究

目的 探讨Ｐ５０在癫痫患者检测中的临床价值。方法 对２５例癫痫患者进行Ｐ５０测试,分析Ｐ５０波的潜伏明和波幅以及在不同刺激频率时Ｐ５０波幅的比率。选择年龄、性别２与患者组相匹配的２５名健康受试者对照组,结果 癫痫患者组Ｐ５３波的潜伏期较长,波幅则显著减低,其中以１８例颞叶癫痫２表现显著,７例额叶癫痫２不明显。刺激频率稍加快时,患者组Ｐ５０的波幅比率明显减小。结论Ｐ５０波的潜伏期和以应异常与颞叶功能     

Antiepileptic drug treatment in the nineties in The Netherlands.

In this review the state of the art of treating patients with epilepsy in the nineties in the Netherlands is presented. It describes general strategies for treatment with antiepileptic drugs and the history of development of the classical anticonvulsant drugs. Eight new drugs, including vigabatrin, lamotrigine, felbamate, oxcarbazepine, gabapentin, tiagabine, levetiracetam and topiramate are discussed. A review of their pharmacological and clinical properties is presented. Dutch experience with these drugs is included.     

Hippocampal loss of the GABAA receptor α1 subunit in patients with chronic pharmacoresistant epilepsies

Alterations of gamma aminobutyric acid (GABA)-mediated neurotransmission have been implicated in the pathogenesis of epilepsies. Here we examine the distribution of the GABA_A receptor in the hippocampus of 78 surgical specimens from patients with chronic pharmacoresistant focal epilepsies. The receptor was localized immunohistochemically with the monoclonal antibody bd-24 which selectively recognizes the ₁ subunit of the GABA_A receptor. The results were compared with the receptor distribution of 28 normal hippocampal specimens obtained at autopsy. In the great majority of the surgical specimens a loss of GABA_A receptor immunoreactivity was present in CA1 (92.3%), CA4 (78.2%), the dentate granular cell layer (70.5%) and the molecular layer of the dentate gyrus (65.4%). The subiculum revealed a normal staining pattern in all but 4 cases. In no instance did we observe an increase of immunoreactivity in any region or cell population. The decrease of GABA_A receptor immunoreactivity was closely related to neuronal loss in the respective specimen and to Ammon's horn sclerosis. There was no correlation between GABA_A receptor loss and the patient's age at surgery, duration of seizures, age at onset of seizures and to the presence or absence of secondary generalized tonic clonic seizures. The data suggest that the observed loss of GABA_A receptor immunoreactivity is a secondary phenomenon rather than an event that is relevant for the pathogenesis of epileptic seizures.     

Drug effects on response duration differentiation I: differential effects of drugs of abuse

Rats were trained to respond under a response duration differentiation schedule in which responses on a lever were reinforced if lever press durations were greater than or equal to 1.00 s but were also less than 1.30 s. Dose-effect curves were generated for cocaine, methamphetamine, pentobarbital, phencyclidine, delta-9-tetrahydrocanninabol (⁹-THC), and morphine. All drugs produced dose-dependent decreases in accuracy (the percentage of total response durations that were reinforced); however, the degree to which changes in accuracy were accompanied by changes in response rates varied among drugs. Pentobarbital and morphine affected primarily longer (> 1.3 s) response durations, phencyclidine and ⁹-THC affected primarily shorter response durations, whereas cocaine and methamphetamine affected both shorter and longer response durations. High doses of methamphetamine and cocaine increased the dispersion of response duration distributions with increasing dose, whereas higher doses of pentobarbital, ⁹-THC and morphine did not increase dispersion of response duration distributions as much. These data show that behavior under this novel schedule is differentially sensitive to a number of pharmacologic manipulations, and that the schedule can provide a useful addition to the analysis of drug effects upon behavior.     

Modulation of action potential duration by inhibition of the transient outward current in sheep cardiac Purkinje fibers

In sheep cardiac Purkinje fibers concentration-dependent inhibition of transient outward current (i_to) by 4-aminopyridine (4-AP, 3-1000 mol/l) was recorded with the two-microelectrode voltage-clamp technique, and correlated effects on action potential duration measured at — 70 mV (APD-70) were investigatigated.Half-maximal inhibition of i_to-amplitude occurred at 15 mol/l 4-AP. The drug exhibited no major effect on voltage-dependent control of inactivation but reduced the maximally available i_to-current. At different activation frequencies (0.05 Hz, 0.25 Hz, 1 Hz) an equal amount of i_to-current, measured as percentage of the respective control, was inhibited by 4-AP. The APD-70 was on the average increased by 4-AP (3–500 mol/l) in a concentration-dependont manner up to 151 % of control. The drug-induced prolongation, measured as percentage of the respective control, was independent of stimulation frequency (0.05 Hz, 0.25 Hz, 1 Hz). Prolongation of APD-70 was on the average more pronounced for short action potentials (APD-70<150 ms: 169 % of reference) than for longer ones (APD-70 150–300 ms: prolongation to 117 % of reference; 500 mol/l 4-AP; 0.25 Hz stimulation rate). Few long control signals (APD-70 >300 ms) were shortened by 4-AP. These results indicate that inhibition of i_to-current by appropriate drugs will result in a reduction of inhomogeneity of action potential duration.     

Effect of age and disease duration on parkinsonian motor scores under levodopa therapy

Summary One hundred and fifty patients suffering from Parkinson's disease were analysed for the expression of the motor symptoms during optimum response to levodopa therapy (subscale III of the Unified Parkinson's Disease Rating Scale). Patients were grouped according to age (64, 65–74, 75 years). Disease duration and daily levodopa dosage were similar in the three groups. Pooled residual scores for posture and gait impairment (PGI), tremor (T), rigidity (R) and distal motor impairment (DMI; hand and foot movements) increased with age (Kruskal-Wallis ANOVA). The parkinsonian scores were significantly higher than the scores of 150 age-matched normal controls (Mann-Whitney U test). The differences between the patients' scores and the scores of the age-matched controls increased with age. In spite of a significant increase in the daily levodopa dosage with disease duration (linear regression), PGI aggravated age-dependently, and DMI age-independently with symptom duration (Spearman rank correlation). In contrast, T and R did not increase with disease duration.