External oxidation pathway in nerve tissue

Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Val'dman.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 431–433, April, 1989.     

Correlation Between Regional Specificity of Antisperm Antibodies to the Spermatozoan Surface and Complement-Mediated Sperm Immobilization

ABSTRACT: Sera from men at risk for immunity to spermatozoa were screened for antisperm antibodies by immunobead binding following passive antibody transfer to antibody-free sperm of fertile donors. The percent motile sperm after incubation in diluted antibody positive serum in the presence of complement was compared with the regional distribution of immunoglobulins bound to the sperm surface. The extent of complement-mediated sperm immobilization varied with immunoglobulin class and with the location of antibody bound to the sperm surface. Tests utilizing complement-mediated immobilization of sperm are insensitive to the presence of antibodies of IgG and IgA classes that are directed against the head, the distal one-fifth of the sperm tail principal piece, or the tail end piece. A high degree of immobilization was found only when IgG binding occurred on the distal two-fifths to three-fifths of the principal piece of the tail or when IgM bound to the sperm tail end piece.     

Covalent immobilization of proteins onto photoactivated polystyrene microtiter plates for enzyme-linked immunosorbent assay procedures

Enhancement of the speed and sensitivity of an ELISA technique was achieved by doing it on a polystyrene microtiter plate preactivated by a simple photochemical reaction. Immobilization of Epicoccum nigrum antigen (allergenic antigen) or goat anti-rabbit IgG onto the photoactivated plates was found to occur in only 45 min with higher binding than that obtained through adsorption during the same period onto the untreated surface. Nearly 1.5-2-folds higher readings were obtained when the ELISA was carried out with the solid phase prepared on the photoactivated surface rather than on the untreated surface. Moreover, solid phases prepared on the activated surface could detect IgE (E. nigrum antibody) even at 1/50 (v/v) dilutions, whereas a solid phase prepared on the untreated surface failed to do so. Around three times higher ELISA values were obtained in the activated plate than the untreated plate when IgE was diluted to 1/5 (v/v). Such photoactivated surface could be of great importance in diagnostic tests involving the ELISA technique particularly to confirm false negative cases and for other immunoassays such as radioimmunoassay procedures.     

长程体外反搏对高胆固醇血症猪高级氧化蛋白产物和高敏C反应蛋白的影响

目的探讨长程体外反搏对高胆固醇血症猪血清中高级氧化蛋白产物(AOPP)和高敏C反应蛋白(hs-CRP)的影响.方法 18头雄性乳猪随机分为正常饲养组(n=6)、高脂饲养组(n=6)及高脂饲养+体外反搏组(n=6).后2组通过高脂饲养复制高胆固醇血症猪模型并对高脂饲养+体外反搏组进行36 d共36 h的长程增强型体外反搏.分别于分组饲养前、反搏前、反搏中期和反搏结束时留取3组动物静脉血,采用分光光度法检测血清AOPP浓度,采用乳胶凝集反应法检测血清hs-CRP浓度.结果高脂饲养组和高脂饲养+体外反搏组经高脂饲养后血清总胆固醇和低密度脂蛋白明显升高(P<0.05).血清AOPP和hs-CRP浓度在分组饲养前组差异无统计学意义(P>0.05).反搏前、反搏中期和反搏结束时,高脂饲养组与高脂饲养+体外反搏组血清AOPP和hs-CRP浓度较正常饲养组同时期均有显著增高(P<0.05);而反搏中期和反搏结束时高脂饲养+体外反搏组血清AOPP浓度较高脂饲养组显著降低[(95.38±12.66)μmol/L比(128.46±12.55)μmol/L;(85.78±10.33)μmol/L比(158.22±16.32)μmoL/L,P<0.05];且反搏中期和反搏结束时高脂饲养+体外反搏组血清hs-CRP浓度较高脂饲养组也有显著降低[(0.47±0.14)mg/L比(0.62±0.32)mg/L;(0.47±0.16)mg/L比(0.59±0.43)mg/L,P<0.05].结论 AOPP和hs-CRP参与了高胆固醇血症猪的发病过程.长程体外反搏可能通过减轻机体体内氧化应激和微炎性反应过程,从而阻止高胆固醇血症的病理生理进程.     

髂前下棘的解剖及其在骨盆骨折外固定中的应用

目的:对髂前下棘进行应用解剖学研究,为骨盆外固定钉直径的选择和微创置钉技术提供参考依据.方法:对22例44侧骨盆的髂前下棘进行观察测量,获取髂前下棘横、矢径,以及体表投影等数据,按性别分组进行统计学处理.所得数据应用于26例骨盆骨折外同定手术.结果:男性髂前下棘横、矢径分别为(12.23±1.91)mm和(20.09±2.43)mm;女性分别为(11.05±1.56)mm和(19.25±1.85)mm.男性髂前下棘在髂前上棘下方(29.49±7.66)mm,内侧(21.79±6.48)mm;在耻骨结节上方(51.70±9.31)mm,外侧(67.74±5.36)mm.女性髂前下棘在髂前上棘下方(23.74±8.89)mm,内侧(16.86±8.92)mm;在耻骨结节上方(43.93±9.04)mm,外侧(70.16±6.39)mm.依据本研究数据对26例骨盆骨折髋臼上方行外固定手术.有效的减少术中放射学暴露和手术时间.结论:根据解剖学测量数据进行固定钉选择和术中定位,使得髋臼上置钉外固定支架可迅速准确实施,适应骨盆骨折急诊处理的需要.     

聚醚砜表面光固定脲酶的研究

我们利用含芳香叠氮基的光活性酯将脲酶光固定在聚醚砚（Polyether sulfone,PES）膜的表面。同时研究了紫外光辐照时间对固定化脲酶密度、固定化脲酶活性的影响，温度、PH值对自由脲酶、固定化脲酶相对活性的影响；并考察了固定化脲酶的相对活性随光活性酶浓度的变化、固定化脲酶的重复使用次数及储存稳定性等性质。结果表明，PES膜表面固定化脲酶的浓度为0.33mg/cm^2；当紫外光辐照时间为5分钟时，固定化脲酶的相对活性最高；固定化脲酶的最适Ph值和最适温度分别为7℃和50 ℃；在50℃时，连续使用12次后，固定化脲酶仍具有50%的催化活性；在4℃保存储存一个多月仍可保持80%的催化活性。     

Three-dimensional pseudospectral modelling of cardiac propagation in an inhomogeneous anisotropic tissue

Various investigators have used the monodomain model to study cardiac propagation behaviour. In many cases, the governing non-linear parabolic equation is solved using the finite-difference method. An adequate discretisation of cardiac tissue with realistic dimensions, however, often leads to a large model size that is computationally demanding. Recently, it has been demonstrated, for a two-dimensional homogeneous monodomain, that the Chebyshev pseudospectral method can offer higher computational efficiency than the finite-difference technique. Here, an extension of the pseudospectral approach to a three-dimensional inhomogeneous case with fibre rotation is presented. The unknown transmembrane potential is expanded in terms of Chebyshev polynomial trial functions, and the monodomain equation is enforced at the Gauss-Lobatto node points. The forward Euler technique is used to advance the solution in time. Numerical results are presented that demonstrate that the Chebyshev pseudospectral method offered an even larger improvement in computational performance over the finite-difference method in the three-dimensional case. Specifically, the pseudospectral method allowed the number of nodes to be reduced by ≈85 times, while the same solution accuracy was maintained. Depending on the model size, simulations were performed with ≈18–41 times less memory and ≈99–169 times less CPU time.     

Quaternion-based strap-down integration method for applications of inertial sensing to gait analysis

The proposed strap-down integration method exploits the cyclical nature of human gait: during the gait swing phase, the quaternion-based attitude representation is integrated using a gyroscope from initial conditions that are determined during stance by an accelerometer. Positioning requires double time integration of the gravity-compensated accelerometer signals during swing. An interpolation technique applied to attitude quaternions was developed to improve the accuracy of orientation and positioning estimates by accounting for the effect of sensor bias and scale factor drifts. A simulation environment was developed for the analysis and testing of the proposed algorithm on a synthetic movement trajectory. The aim was to define the true attitude and positioning used in the computation of estimation errors. By thermal modelling, the changes of bias and scale factor of the inertial sensors, calibrated at a single reference temperature, were analysed over a range of ±10°C, for measurement noise standard deviations up to σ_g = 2.5° s⁻¹ (gyroscope) and σ_a = 0.05 m s⁻¹ (accelerometer). The compensation technique reduced the maximum root mean square errors (RMSEs) to: RMSE_θ=14.6° (orientation) and RMSE_d=17.7 cm (positioning) for an integration interval of one gait cycle (an improvement of 3° and 7 cm); RMSE_θ=14.8° and RMSE_d=30.0 cm for an integration interval of two gait cycles (an improvement of 11° and 262 cm).     

Laterality of 40 Hz EEG and EMG During Cognitive Performance

Task-dependent lateralization of the 40 Hz EEG rhythm was investigated in 15 right-handed male adults during the performance of verbal analogy and geometric figure rotation tasks. Forty Hz EMG recorded from the temporal and splenius muscles was similarly examined. Results indicate that 40 Hz EEG is asymmetrically distributed during cognitive performance, varying as a function of cognitive processsing. The range of laterality scores also varied by condition, with the largest variation present during baseline conditions and smallest recorded during the presentation of the verbal analogies task, suggesting that individual cognitive styles tend to vary more during less structured situations. No relationship between 40 Hz EMG and task was obtained.