Neurofilament heavy-chain NfH(SMI35) in cerebrospinal fluid supports the differential diagnosis of Parkinsonian syndromes.

We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes.     

INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA

1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain.     

人体液中喷布洛尔及其代谢物的GC/MS分析

用气相色谱一质谱联用(GC-MSD)系统分析方法检出了人尿中喷布洛尔的6个羟化代谢物,用Scp-Pak柱提取的方法检出了人血浆中的原型药物。并从分子结构上对此药物的代谢途径进行了研究。尿中提取和血中提取的回收率分别为90.83.%和85.88%,Gc-MSD的检测限为5pg。本方法适用于运动员兴奋剂的系统检查。     

多复指数模型及其在EEG数据分析中的应用

由头皮上电极所记录下的EEG信号是大脑中各种电活动,尤其是神经元电活动,互相耦合而产生的电位变化的整体反映。有一种看法认为,表面看来随机、无规则的EEG信号,实际上它的变化只是由少量几个动力学参量控制着的非线性过程。根据这个假定,我们提出使用多复指数(MCE)模型来描述EEG信号的想法。文中首先简要地介绍了用来估计时序信号MCE模型参数的非调和Fourier展开算法(NHFE)的基本思想。然后,对一个叠加有白噪声、具有4个频率成分的模拟信号,用NHFE算法估计出其MCE模型参数,并把所得的结果与用经典的周期图谱分析方法、AR模型谱分析方法所得到的信号频谱作了比较。结果表明,在SNR高的条件下,NHFE算法所估计出的模型参数能更客观地反映信号的固有特性。基于目前的有关EEG形成的假设,应用MCE模型来描述EEG将更能反映出其特征。因此,我们对MCE模型及其参数在EEG数据分析中的几种可能应用作了初步尝试。这些应用包括:EEG信号段(或一段诱发电位,或一段事件关联电位)的特征参数的提取,这些特征参数包括优势频率值、独立的频率成分个数、幅度值、正负衰减指数的个数、频带宽度与幅度乘积(能量);EEG的频率调制特性的粗略描述等。从而看到了用通常信号分析方法所看不到的EEG信号中所反映的大脑活动的变化。由于用MCE模型及其参数来描述EEG的方法更符合目前关于大脑非线性动力学行为的假设,所以这一方法将是表示EEG信号的有效途径之一。另外,MCE模型方法在EEG信号的模拟研究与数据压缩等方面也将是有用的。文中还讨论了NHFE算法应用中的一些问题。     

Superoxide production by human eosinophils can be inhibited in an agonist-selective manner.

This paper focuses on eosinophil activation and its selective inhibition. Superoxide anion (O2-) production by human eosinophils, an indicator of their activation, was induced by a variety of activators. Several compounds which are known to inhibit protein kinase C (staurosporine, K252a, sphingosine) inhibited O2- production induced by phorbol ester (PMA) but failed to inhibit O2- production induced by IgG coupled to Sepharose beads. Inhibition of O2- production by other agents (plasma-activated zymosan, fMLP, and leukotriene B4 (LTB4), was intermediate. By contrast, wortmannin, a compound which has been previously reported to inhibit O2- production in neutrophils via a protein kinase-independent pathway, potently inhibited O2- production in eosinophils which had been activated by IgG and by Platelet-Activating Factor but was virtually inactive against PMA-induced O2- production. Taken together, the results indicate that, as a minimum, there must be two pathways of induction of O2- production in eosinophils. Moreover, the intermediate levels of inhibition in cells which had been activated with serum-activated zymosan, FMLP, and LTB4 suggest that these agents may either be acting via both of these pathways or that yet other pathways may exist.     

Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance

Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.