Frontotemporal dementia and parkinsonism linked to chromosome 17 with the N279K tau mutation

We present a case of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) harboring the N279K mutation in the MAPT gene from the family known as pallido‐ponto‐nigral degeneration (PPND). This 49‐year‐old man was followed for 17 years. He presented at age 41 years with left leg stiffness and en‐bloc turning. During the course of his illness he developed a constellation of symptoms including parkinsonism, pyramidal signs, vertical gaze palsy, dysphagia, dystonia, personality and cognitive dysfunction, weight loss and mutism. Gross neuropathological examination showed mild atrophy of the cerebral cortex, hippocampal formation, amygdala, thalamus, subthalamic nucleus and depigmentation of the substantia nigra. Microscopy revealed neuronal loss and gliosis in the same regions. Tau immunohistochemistry showed pretangles, numerous threads, grain‐like structures and oligodendroglial tau‐positive inclusions (“coiled bodies”). In the spinal cord the tau pathology was more abundant in gray than white matter. Pretangles and threads were present in the anterior and, to a lesser extent, in the posterior horns. FTDP‐17 should be suspected in patients with a history of familial parkinsonism combined with behavioral and cognitive changes, onset before age 65 years and an aggressive clinical course.     

Single unit activity in the auditory cortex of a monkey performing a short term memory task

Summary Short term memory to tones (STMT) was investigated by recording single unit activity in the auditory cortex of a behaving monkey. The activity of each unit was studied in two behavioral conditions: a) During task performance, the monkey had to compare two tones separated by one second of silence (inter-stimulus interval), b) During a nonperforming period; the monkey heard the two tones but did not respond behaviorally. It was noted that the firing rate of many units during the inter-stimulus interval (ISI) was dependent on the frequency of the first tone. Such dependency was observed even towards the end of the ISI, both during task performance trials (50% of the units) and during the nonperforming period (32% of the units). The activity of these units could be the basis of STMT in both of these behavioral states. In 65% of all the units tested, the responses during the ISI were of a higher magnitude in the performance period than were the responses in the non-performance period. The activity of these units may be related either to general processes such as attention and expectation or to short-term memory processes. During task performance, the responses of 23% of the units to the second tone were dependent on whether its frequency was identical to that of the first tone. Such dependency was never observed during the non-performing period. These units may detect similarity or non similarity between two tones presented one second apart. Periodic patterns of firing were not found in the study, thus suggesting that the ISI responses were not generated by reverberatory activity in simple closed loops. On the basis of these results, several alternative mechanisms of STMT are suggested.     

后装机出源阻力大故障分析及维修

从机械和电路两方面分析了 KLHZ-001型后装机出源阻力大的原因 ,并分别阐述了维修办法.     

膜生化反应器处理垃圾焚烧厂渗沥液的试验研究

采用成套膜生化反应器(MBR)小试设备对垃圾焚烧厂的渗沥液处理进行了可行性试验研究,并选取了COD、NH3-N的去除率作为主要考察指标.试验表明:膜生化反应器(MBR)工艺技术可行,COD、NH3-N的去除率分别可达99%和98%以上,其出水指标分别达到GB 16889-1997生活垃圾填埋污染控制标准中的三级和二级标准.     

基层医院组建卒中小组的初步探讨

目的总结探索在基层医院组建卒中小组，治疗急性脑卒中的模式。方法组建包括社区网络在内的院内卒中小组，对脑卒中患者进行动态的全面评估和系统的个体化治疗。结果规范了急性脑卒中的临床治疗行为，改善了患者预后。结论在基层医院建立卒中小组是一种可行的治疗模式。     

小鼠持续性脑缺血后NMDA受体亚单位表达的变化

目的：研究小鼠持续性脑缺血后不同脑区NMDA受体亚单位表达的变化及其与病理损伤之间的联系。方法：采用大脑中动脉阻断法制作小鼠持续性脑缺血模型，取缺血后不同时间的皮层、海马、皮层下脑组织，用免疫印迹技术测定NMDA受体亚单位ζ1和ε1及ε2蛋白的含量。同时作冰冻切片和苏木素伊红染色，计算相应脑区神经元密度。结果：NMDA受体ζ1和ε1及ε2亚单位表达的改变发生于缺血后5h内，皮层下3个亚单位表达均明显增加，海马则各亚单位表达变化不一。脑梗塞灶和相关脑区神经元密度显著减小均出现于缺血后5h，相关脑区神经元死亡严重程度依次为皮层下组织和海马CA1区及大脑颞叶皮层Ⅲ－Ⅳ层。结论：小鼠持续性脑缺血，缺血侧脑组织NMDA受体亚单位ζ1和ε1及ε2表达的变化发生在明显的病理损害之前，表达变化程度因脑区不同，与相关脑区神经元损害的程度相应。     

Heparin effect on ionised calcium concentration

The effect of heparin on plasma ionised calcium was studied by adding it in increasing amounts to whole blood from 10 normal subjects. There was no significant change in ionised calcium from the addition of 1 U/ml but a significant fall of 0.02 mmol/1 when 2 U/ml were added and a progressive further fall with increasing concentrations. Heparin from three different manufacturers produced similar results. The effect of heparinisation in vivo was studied during regular haemodialysis on 10 patients with chronic renal failure. Following intravenous injection of 10000 U of heparin there was a consistent and significant fall averaging 0.03 mmol/l.     

Neuromuscular transmission as a function of motor unit size in patients with prior poliomyelitis.

We studied neuromuscular transmission in 16 patients with prior poliomyelitis by measuring single fiber electromyographic (SFEMG) jitter. This was compared with 3 indirect methods of assessing reinnervation: SFEMG fiber density, macro EMG, and the presence of fiber type grouping on muscle biopsy. In patients with acute poliomyelitis before the age of 10, there was a positive correlation between the extent of neuromuscular transmission impairment, demonstrated by increased SFEMG jitter, and the enlargement of the motor unit, as indicated by increased fiber density, increased macro EMG signals, and fiber type grouping on muscle biopsy. However, there was no correlation between any of these parameters and the presence or absence of new symptoms of weakness. These findings suggest that impaired neuromuscular transmission is most common in patients with prior poliomyelitis whose motor units have been maximally enlarged by axonal sprouting, but is independent of the presence or absence of new symptoms of weakness.     

Spermidine/Spermine N-Acetyltransferase, a New Biochemical Marker for Epithelial Proliferation in Rat Bladder

We examined the activity of spermidine/spermine N ¹-acetyltransferase (SAT), a rate-limiting enzyme of the biodegradation of polyamines, in N -butyl- N -(4–hydroxybutyI)nitrosamine-induced transitional cell carcinoma (TCC) and melamine-induced papillomatosis of rat bladder, and compared the activity to that of ornithine decarboxylase (ODC). Both activities were higher in both lesions than in control rats. The difference between SAT and ODC activities in cancerous tissue and papillomatosis was not significant. Cells stained for proliferating cell nuclear antigen (PCNA) were abundant in papillomatosis. TCC had areas with much PCNA. The results indicated that an elevation of SAT activity occurs in both reversible and irreversible proliferation of bladder epithelium and could be important in bladder carcinogenesis.     

Stressors in ICU: patients’ evaluation

Objective: To study the physical and psychological stressors in the intensive care unit (ICU) and to correlate stressors with different demographic variables. Design: Cross-sectional analytical survey. Setting: Intensive care unit of a private hospital. Patients and participants: 50 randomly selected ICU patients during the first week of their ICU stay. Measurements and results: The Intensive Care Unit Environmental Stressor Scale was administered to 50 patients. Pain and the impossibility of sleeping due to noise and having tubes in the nose and mouth were considered the most important physical stressors. Loss of self control and lack of understanding about the attitudes and procedures were the main psychological stressors. Conclusions: Interventions should be aimed at relieving the patient's pain and at controlling the level of noise to make sleep possible. From the psychological standpoint, the independence of the patient should be encouraged, thus stimulating the recovery of self-control. The team should also inform the patient about the procedures which will be carried out. Received: 1 April 1997 Accepted: 24 September 1997