Prospective randomized study of D-Trp6-LHRH versus buserelin in long desensitization protocols for medically assisted conception cycles

In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.     

Behavioral dissociation of anterodorsal and posteroventral hippocampus by subseizure stimulation in mice

BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility.     

Comparison between laser and electrical ablation of ventricle in dogs: Hemodynamic,pathologic and electrocardiographic observations

Summary To characterize and compare the pathologic, hemodynamic and electrocardiographic changes of both transeatheter laser and electrical energy on ventricle, 33 subendocardial myocardium lesions were induced at energy 60, 120 and 240 Joules by either transcatheter laser irradiation or electrical shock in 7 anesthetized dogs. The following results were observed: 1) Both laser and electrical ablation on myocardium created nonhomogeneous myocardium injury, but laser ablation caused mainly focal tissue vaporization and necrosis, while electrical shock induced widespread tissue degenerations; 2) Both laser and electrical induced-lesion dimensions increased parallel to the total dosage of energy; 3) Laser ablation caused mainly (90%) single ventricular premature beats and 86 % of them occurred within the first minute after energy discharged, while ventricular tachycardias were found in any electrical energy groups; ventricular fibrillations occurring during laser and electrical ablation were 5 % and 13 % respectively (P< 0.01): 4) A decrease in aortic blood pressure and an increase in central verous pressure induced by laser ablation were significantly less than that produced by the same amount of electrical energy (P<0.0l). Our preliminary results have shown that transeatheter laser ablation has great potential for becoming a practical method in the management of refractory tachycardias.     

阈下刺激定位慢径消融靶点的临床应用研究

目的 :探讨利用阈下刺激 (STS)定位房室结折返性心动过速 (AVNRT)的慢径消融靶点的临床应用价值。方法 :选择AVNRT患者 6例 ,经常规电生理检查明确诊断后 ,将大头电极放在冠状窦口下缘与希氏束之间的中下区域进行标测 ,测定该点的起搏阈值后 ,诱发AVNRT ,然后发放STS终止AVNRT ,在终止位点处试消融 ,观察STS标测消融的有效性 ;在非终止位点处 ,结合局部心内电图判断是否进行试消融 ,如在非终止位点处试消融 ,观察STS标测的可靠性。同时观察STS标测定位的安全性。结果 :在 6例患者中 ,有 3例STS终止了持续性AVNRT ,且在终止位点处试消融并获得成功 ;有 5例共在 10个位点处发放了STS ,其中在 9个位点未终止心动过速 ,在这些非终止位点处试消融均未获得成功 ,非 1个位点出现了心房夺获。所有患者在STS标测过程中 ,未出现心房颤动、心动过速的加速或心室颤动等现象。结论 :STS终止AVNRT的位点是判断消融靶点的一个良好的电生理学指标。STS标测定位是安全、有效和可靠的一种方法 ,值得进一步地深入研究     

Elevated threshold for intracortical inhibition in focal hand dystonia.

Differences between control and focal hand dystonia (FHD) subject groups in short interval intracortical inhibition (SICI) as determined by paired transcranial magnetic stimulation (TMS) can be difficult to demonstrate, due to interindividual differences. The purpose of this study was to compare two TMS methods for assessing SICI in 8 control and 7 FHD subjects. Electromyographic (EMG) data were recorded from the first dorsal interosseous (FDI) muscle of the dominant hands of the control subjects and affected hands of the FHD subjects. The first method used a conventional approach of setting conditioning stimulus intensity to 80% of rest threshold (RTh) and test stimulus intensity to 120% RTh. Three interstimulus intervals (ISIs) were used: 2 msec, 3 msec, and the ISI between 2 and 3 msec that produced optimal SICI. The second method was novel in that test stimulus intensity was set to 150% active threshold (ATh), and conditioning stimulus intensity was varied between 50% and 100% ATh. The latter was determined at the threshold for SICI and expressed as a ratio of ATh. There was no difference between the subject groups in the degree of SICI produced using the first method, at the three ISIs studied. However, using the second method, the SICI threshold:ATh ratio was found to be significantly higher for FHD subjects. This finding suggests that determining the SICI threshold:ATh ratio may be a more sensitive measure of intracortical inhibitory function than more conventional methods.     

Cross talk in surface electromyograms of human hamstring muscles.

Signals generated from muscles other than the muscle(s) of interest (cross talk) can confound the interpretation of surface electromyograms (EMGs). In this study, the amount of cross talk in surface EMGs of human hamstring muscles was estimated using a protocol in which the quadriceps femoris was electrically stimulated via the femoral nerve. EMGs were recorded from the vastus lateralis and the medial and lateral hamstring muscle groups. The amplitude of the EMG response of the vastus lateralis to electrical stimulation was adjusted to match that of its maximum voluntary effort (MVE) under isometric conditions. Subsequent power density spectrum analysis showed that the median frequencies of the signals generated by electrical stimulation and MVE were not significantly different. In conventional bipolar recordings, cross talk in lateral hamstring EMGs averaged 17.1% MVE and in medial hamstring EMGs 11.3% MVE (average-rectified values). The double differential technique significantly reduced cross talk to 7.6% MVE for the lateral hamstrings, and to 4.2% MVE for the medial hamstrings. The double differential technique appears to be more selective than the bipolar technique when recording EMGs from muscles with highly active neighbors and thus should be used in such situations. Software simulations of the double differential technique also appear to be more selective than the bipolar technique and may be used when the number of amplifiers available is limited.     

Anticonvulsant properties of the cerebrospinal fluid due to antiepileptic system activation

Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Department of Pathological Physiology, N. I. Pirogov Odessa Medical Institute. Translated from Byulleten' Éksprimental'noi Biologii i Meditsiny, Vol. 106, No. 8, pp. 146–149, August, 1988.     

不同时辰刺激大鼠的交叉上核对血浆中皮质酮含量的影响

应用拉丁方设计，在不同体重组的大鼠，于不同时辰，对交叉上核采取不同强度的刺激，用放射免疫法测定外周血中皮质酮的含量。其结果显示：各体重组间无显著性差异，不同时辰血浆皮质酮的平均含量各组呈现基本相同的节律性变化，无论何时辰刺激交叉上核使之兴奋，均可显著提高血浆皮质酮的含量。完全损毁交叉上核后７２小时血浆皮质酮含量和正常对照组无显著性差异，且其节律性也没有出现明显变化。     

Neurokinin A with K channel blockade potentiates contraction to electrical stimulation in human bronchus

This study investigated the effects of neurokinin A (NKA) on cholinergic neural responses in human bronchus. NKA (0.1 nM) did not alter the contractile response to submaximal electrical field stimulation. However, K⁺ channel blockade with 4-aminopyridine (4-AP) (0.1 mM) potentiated the response to electrical field stimulation (to 182 ± 25% of control, n = 4, P < 0.05) and subsequent addition of NKA in the presence of 4-AP produced further potentiation (to 123 ± 6% of the response to 4-AP n = 4, P < 0.05). Neither 4-AP (0.01 or 0.1 mM) nor NKA in the presence of 4-AP potentiated the actions of exogenous acetylcholine but in these experiments 4-AP itself produced a marked direct contractile response. Thus NKA in the presence of K⁺ channel blockade potentiates cholinergic neural response in human bronchus and this occurs at a prejunctional site.     

THE INFLUENCE OF MULTIPLE FACTORS ON GALL BLADDER PRESSURE AFTER AURICULAR POINT STIMULATION

The study has explored 11 correlative variables which might affect the gallblad-der pressure GBP of patients with gall stone after auricular electrical stimulation by means of multiplestepwise regression. It was found that the size of gallbladder stone (X9), cholecystolithiasis (X4),sex (X1), and the baseline of GBP (X10) could affect the GBP change range (Y1) depressingly orreinforcingly. Also the baseline of GBP (Y1) could be affected by the variables X1 (sex), X2 (age),and X6 (long diameter of the gallbladder, LDGB), etc.. The result shows that the change in GBPafter auricular electrical stimulation is comprehensively influenced by multiple factors. And it providessome useful information for predicting the curative effect of auricular therapy on gallbladder stone inclinic.