Depletion of brain norepinephrine: differential influence on anxiolyic treatment effects

Rationale: Previous studies have demonstrated that anxiolytic-like anticonflict effects can be produced by either (1) acute administration of traditional anti-anxiety compounds (benzodiazepines or barbiturates) or (2) chronic administration of tricyclic (TCA) or monoamine oxidase inhibitor (MAOI) antidepressants. Objective: The present study determined the effects of noradrenergic neuronal depletion on these distinct anticonflict treatments. Methods: After 3 weeks of training in a repeated measures drink suppression conflict paradigm, water-restricted rats consumed 11–14 ml water/session (unpunished responding) and accepted 25–40 shocks/session (punished responding) during control (i.e., non-drug) 10-min test sessions. The noradrenergic neurotoxin DSP4 [N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride; 65 mg/kg, IP] or its vehicle (saline; 1 ml/kg) was administered after 3 weeks of conflict testing. Conflict behavior was then evaluated for 8 weeks post-treatment. In separate groups of DSP4- and vehicle-pretreated subjects, the effects of acute administration (10-min pretreatment) of phenobarbital (5–40 mg/kg) or alprazolam (0.3–2.5 mg/kg) were determined. In a third experiment, the effects of chronic treatment with the TCA desipramine (DMI; 5 mg/kg, twice daily for 8 weeks) or the non-selective MAOI phenelzine (4.0 mg/kg, twice daily for 8 weeks) on conflict behavior were determined in additional groups of DSP4- or vehicle-pretreated subjects. Results: DSP4 treatment produced a modest yet statistically significant decrease in punished responding (i.e., anxiogenic-like effect) relative to vehicle controls. DSP4 pretreatment did not alter the anticonflict effects of acute alprazolam or phenobarbital treatment. In contrast, DSP4 treatment completely abolished the anticonflict effects produced by chronic DMI or chronic phenelzine treatment. Conclusions: Thus, noradrenergic neuronal integrity appears to be required for the anxiolytic-like effects of chronic antidepressant treatment, but not for the anxiolytic-like effects of acute treatment with barbiturates and benzodiazepines. Received: 6 August 1998/Final version: 16 October 1998     

T-maze learning, spontaneous activity and food intake recovery following systemic administration of the noradrenaline neurotoxin, DSP4

Following systemic administration of the noradrenaline (NA) neurotoxin, DSP4 (50 mg/kg), rats were found to be retarded in the rate at which they acquired the "right-turn" running response in a modified T-maze choice situation, as measured by the total number of errors per session and median latency to reach the goal box. Desipramine (DMI, 20 mg/kg), injected 30 min before DSP4 blocked the acquisition retardation. DSP4 was found to have a short-lasting effect upon spontaneous motor activity, while food and water intake recovery was complete within 7 days of the injection. Both the NA-accumulation data and endogenous NA concentrations indicated profound NA, but not 5-hydroxytryptamine (5-HT) and dopamine (DA), depletions in the cortex, hippocampus and cerebellum. These data seem to confirm the role of the locus coeruleus-noradrenaline (LC-NA) system in an instrumental learning situation.     

基于DSP的人工电子耳语音信号处理的研究

介绍人工电子耳的基本原理和ClS语音信号处理方案,提出基于DSP芯片TMS320LF2407的硬件电路设计和软件编程流程,最后通过计算机对经过DSP处理后的语音数据进行了仿真和合成,实验结果表明合成语音与原始语音在频谱包络特征上非常相似.     

消化道无线内窥镜便携式图像接收装置的硬件设计

消化道无线内窥镜便携式图像接收装置是在TMS320C6211DSP的基础上进行开发的。先对摄像胶囊发出的调制信号进行接收和解调，然后利用视频解码芯片SAA7114H的同步信号，经过时序逻辑变换，控制对断续视频信号的采集，并将其存储到CF卡中。此外．还利用高速DSP对图像信号进行预处理和压缩．可大大节约数据的存储空间和处理时间。     

Diarrhetic Shellfish Poisoning,Washington, USA, 2011

Diarrhetic shellfish poisoning is a gastrointestinal illness caused by consumption of bivalves contaminated with dinophysistoxins. We report an illness cluster in the United States in which toxins were confirmed in shellfish from a commercial harvest area, leading to product recall. Ongoing surveillance is needed to prevent similar illness outbreaks.     

基于FPGA的神经突触的硬件实现及放电性能比较

目前专门对化学突触硬件实现的研究较少,采用FPGA芯片技术硬件实现化学突触,对神经元网络的硬件实现具有重要价值。运用DSP Builder软件,对以Hodgkin-Huxley神经元为突触前神经元和突触后神经元的化学突触数学模型进行建模。在DSP Builder模型的基础上,将化学突触的DSP Builder模型进行合理的拆分,然后分别将各个模块在FPGA所对应的软件环境下进行编译运行,最后下载到FPGA核心芯片中,硬件实现5种基于不同机理的化学突触模型。采用相关系数法,对仿真结果和硬件结果在同一个周期内的突触前神经元动作电位、突触后神经元动作电位以及突触电流的幅值进行对比,验证硬件实现的准确性。5种硬件实现的化学突触均可以较好地传递动作电位,但是各个模型消耗资源不同,模型3所消耗的内部乘法器资源(69%),约为模型5资源(31%)的2倍,表明突触模型数学复杂度越高,其消耗的乘法器资源越多。相关系数法的对比结果显示,模型3相关度最高,为0.791 3,模型4相关度最低,为0.693 5。虽然模型3数学复杂度高、硬件资源消耗多,但是其表现的生物性最好。硬件实现的5种突触模型均能较好地呈现化学突触的单向传递性,其中模型5硬件资源消耗少、相关度高,建议以其作为化学突触硬件实现的首选。     

基于DSP的生物医学信号处理实验平台设计

目的：设计一个实验平台,使生物医学工程专业的学生可以学习在数字信号处理器（DSP）上处理生物医学信号的方法。方法：采用数字化心电信号作为实验平台的数据源,在现有的DSP实验平台上设计完成各种生物医学信号处理算法。结果：在实验平台上开发了心电发生器、滤波、压缩、频谱分析、心率检测等实验．同时将此实验平台作为学习生物医学信号处理仪器设计的原型,取得了良好的教学效果。结论：学生使用基于DSP的生物医学信号处理实验平台既能够学习和深刻理解生物医学信号处理的算法,还能够学习如何使用DSP来实现这些算法,教学效果显著,但仍有待于进一步完善。     

Reliability and validity of measurements of facial swelling with a stereophotogrammetry optical three-dimensional scanner

Volume changes in facial morphology can be assessed using the 3dMD DSP400® stereo-optical 3-dimensional scanner, which uses visible light and has a short scanning time. Its reliability and validity have not to our knowledge been investigated for the assessment of facial swelling. Our aim therefore was to assess them for measuring changes in facial contour, in vivo and in vitro. Twenty-four healthy volunteers with and without an artificial swelling of the cheek were scanned, twice in the morning and twice in the afternoon (in vivo measurements). A mannequin head was scanned 4 times with and without various externally applied artificial swellings (in vitro measurements). The changes in facial contour caused by the artificial swelling were measured as the change in volume of the cheek (with and without artificial swelling in place) using 3dMD Vultus® software. In vivo and in vitro reliability expressed in intraclass correlations were 0.89 and 0.99, respectively. In vivo and in vitro repeatability coefficients were 5.9 and 1.3 ml, respectively. The scanner underestimated the volume by 1.2 ml (95% CI -0.9 to 3.4) in vivo and 0.2 ml (95% CI 0.02 to 0.4) in vitro.     

复心片与复方丹参滴丸治疗稳定型心绞痛的对照研究

目的观察复心片与复方丹参滴丸治疗冠心病稳定型心绞痛的临床疗效,并对其安全性作出评价。方法采用随机对照,治疗组100例给予复心片(2片/次,3次/日)口服,对照组60例给予复方丹参滴丸(10丸/次,3次/日)口服,8周后进行心绞痛,主要症状总疗效及毒副作用评估。结果治疗组对轻、中、重度心绞痛均有很好疗效,总有效率97%,对照组95%,两组比较无明显差异(P>0.05);治疗组心电图总有效率77%,对照组70%(P>0.05)。结论复心片是治疗稳定型心绞痛的有效药物。     

基于DSP Builder的EIT正交序列解调方法与电路设计

目的 设计一种用于电阻抗断层成像技术(EIT)测量的正交序列解调电路用以检测被测信号的模量和相位.方法 利用DSP Builder,在matlab/simulink中搭建模型文件(.mdl),并利用仿真激励验证方法与设计的正确性和合理性;再用Signal Compiler模块读取建模文件,生成VHDL文件和工具命令语言脚本,在Quartus Ⅱ中进行综合、适配、仿真和硬件实现.结果 仿真和测试结果均表明,所设计的正交序列解调电路能够有效提取被测信号的实部信息和虚部信息,在实验误差允许的范围内能很好满足EIT测量的要求.结论 基于DSP Builder的正交序列解调方法与电路设计能够给出EIT实部和虚部信息,为全信息复阻抗测量提供有力的技术支持. Abstract： Objective To design and develop a quadrature demodulation circuit for detection of ampli-tude and phase information in EIT measurement. Methods A model structure file was built in matlab/simulink using the elements in Ahera DSP Builder and verified by simulated stimulation. Then the model file was convert-ed to VHDL file via Signal Compiler, and the synthesis, adaptation, simulation and hardware implementation were accomplished. Results The simulation and testing results show that the circuit can extract the real and imagi-nary information of the measured signal and it also meets the EIT measuring requirement, with acceptable mea-sure error. Conclusion The demodulation circuit based on DSP Builder can precisely give real and imaginary information of EIT and provides technological support for full-information complex impedance measurement.