Delay in simple reaction time after focal transcranial magnetic stimulation of the human brain occurs at the final motor output stage

It is known that the execution of the motor response in a simple reaction time (RT) task can be delayed by transcranial magnetic stimulation (TMS). This paper is aimed at determining the site of action where the delay in RT occurs. A delay in RT was obtained only at those TMS sites over the motor cortex contralateral to the responding hand, which produced also a muscle twitch in the responding hand. The delay in RT covaried with the TMS intensity and increased the closer the time of TMS approached the expected time of reaction onset. Visual and auditory go-signals yielded similar delays in RT, but only when TMS was applied about 40 ms later for the visual go-signal, corresponding to the modality specific difference in RT control values. TMS of the supplementary motor area (SMA) immediately prior to the expected time of reaction onset produced no delay in RT. Spinal excitability as tested by F waves showed a pre-movement facilitation in the control trials which continued seemingly undisturbed during the period of RT delay after TMS. It can be concluded that the delay in RT is not due to SMA stimulation or spinal inhibition but depends on effective stimulation of neural elements in the motor cortex which are active very late in the process of movement release from the final motor output stage.     

Silent brain infarctions in patients with coronary heart diseases. A Spanish population survey

Coronary artery disease is a recognized risk factor for symptomatic ischaemic stroke but the influence on asymptomatic stroke has not been clearly determined. The purpose of this work was to determine the relationship between coronary heart disease and silent brain infarcts and the influence of vascular risk factors and carotid atherosclerosis in a representative sample of Spanish patients with symptomatic coronary artery disease. A consecutive sample of 100 subjects with myocardial infarction, angina or both were included in the survey. Patients with a potential source of emboli from the heart were excluded. As main baseline variables, we considered vascular risk factors; complete cardiological study, including coronary angiography; brain computed tomography (CT) to detect infarcts; echo-Doppler of supra-aortic vessels to detect stenosis; and carotid angiography, when appropriate. As the outcome variable, we observed the incidence of symptomatic stroke after an 18 month mean follow-up. We found silent brain infarction in 30 patients (93% were of lacunar type). None of the vascular risk factors was related to brain infarcts either in univariate or multivariate analysis. Carotid atherosclerosis was the only significant predictor in a model of logistic regression (P < 0.0005), although the lesions were bilateral in the majority of cases. We observed a very low incidence of symptomatic stroke after a mean follow-up of 18 months. Silent brain infarcts are a frequent finding on brain CT in patients with coronary heart disease and are associated with carotid atherosclerosis; however, it does not seem to have important prognostic significance. Received: 28 May 1997 Received in revised form: 9 September 1997 Accepted: 1 October 1997     

西宁地区老年人无症状性心肌缺血与HOLTER监测的临床研究

本文迈过对西宁地区（海拔２２６０ｍ）４７２例老年患者的ＨＯＬＴＥＲ监测，探讨ＳＭＩ的发生与年龄、时间、心率等的关系及其规律，结果表明：该地区老年患者ＳＭＩ及缺血性ＳＴ段总的发生率均高于平原地区，ＳＭＩ多发生于上午及午休后的２～４小时内，静息状态时，ＳＭＩ与有症状性心肌缺血的发生率有显著性差异（Ｐ＜０．０１），缺血性ＳＴ段发生与年龄分布有一定关系，同时还发现，ＳＭＩ患者心肌梗塞的发病率高于有症状性心肌缺血患者的发病率。     

Cerebral neoplasms initially presenting with massive intracerebral hemorrhage

In three patients, clinically silent brain tumors led to massive intracerebral hemorrhage. These patients represented 0.6% of 497 consecutive patients with primary or secondary brain tumors and 2.5% of 119 patients with hypertensive or spontaneous intracerebral hemorrhage. Examination by computed tomography and angiography provided no evidence suggestive of the presence of neoplasms. All three patients were surgically treated and the lesions were histologically confirmed to be metastatic bronchogenic carcinoma, metastatic clear-cell carcinoma and low-grade astrocytoma, respectively.     

Concurrent bilateral projection and activation of motor cortices in a patient with congenital mirror movements: A TMS study

Objectives

Mirror movements (MMs) are unintended and unnecessary movements accompanying voluntary activity in homologous muscles on the opposite side of the body, particularly in distal arm muscles. Congenital MMs may be sporadic or familial. Several mechanisms have been proposed to explain persistent congenital MMs. Hypothesis 1 assumes the existence of an ipsilateral corticospinal pathway, and Hypothesis 2 the activation of both motor cortices. We report a new case of congenital mirror movements in a healthy woman.

Methods

Electromyographic recordings and focal transcranial magnetic stimulation (TMS) were used for neurophysiological evaluation.

Results

Voluntary contraction of either abductor pollicis brevis (APB) elicited mirror activation of the other APB. Focal TMS of either M1 elicited motor evoked potential (MEP) of normal latency and amplitude in both resting APB. TMS of the left cortex upon maximal contraction of the right APB and mirror contraction of the left APB produced interhemispheric inhibition (IHI) in the former and silent period (SP) in the later.

Conclusions

The electrophysiological evaluation using transcranial magnetic stimulation provides evidence of the concurrent action of both mechanisms in this patient.

Significance

The combination of more than one hypothesis could be more appropriate for understanding the underlying mechanism in some MM cases.     

Identification and sequence analysis of discordant phenotypes between AmpFlSTR SGM Plus™ and PowerPlex® 16

During duplicate analysis of buccal swabs from 1,377 individuals with 2 commercial short tandem repeat (STR) kits, we observed 8 discordant phenotypes with SGM Plus (SGM, second generation multiplex) for the STRs THO1 (2), vWA (4) and D18S51 (2), and 1 discrepancy with PowerPlex 16 for D18S51. One individual even showed two discrepancies (vWA and THO1) for SGM Plus. In each case, the difference observed was due to the non-amplification or allele dropout of the second allele in a heterozygous genotype. Sequence analysis revealed each time the presence of a mutation that probably coincided with the primer-binding site. Primer-binding site mutations for vWA and D18S51 have been reported previously, while the mutation for THO1 (C-to-T substitution at position 1286 of GenBank sequence D00269) is reported here for the first time. While the frequency of these silent alleles remains low (0.58% in our study), it is suggested that appropriate measures should be taken for database comparisons and that allelic dropout should be further investigated by sequence analysis and be reported to the forensic community.     

动态心电图对无症状性心肌缺血的诊断价值

目的 探讨动态心电图对无症状性心肌缺血的诊断价值.方法 选取150例诊断为冠心病患者为研究对象,进行24 h动态心电图监测.结果 150例患者监测出心肌缺血发作共1420阵次,其中128例出现980阵次无症状性心肌缺血,平均每例发作（7.66±4.23）阵次,每次发作平均持续时间为（11.2±3.5）min.无症状性心肌缺血白天发作频率为夜间的1.92倍（645阵次vs 335阵次）,且发作时心率较发作前明显上升,差异有统计学意义[（89.4±8.9）/min vs（72.8±8.4）/min,P＜0.05].结论 动态心电图诊断无症状性心肌缺血的敏感性和准确性高,对于防治冠心病有重要临床意义.     

无症状心肌缺血患者动态心电图与冠状动脉CT血管造影的对比分析

目的:比较不同程度无症状性心肌缺血(SMI)患者,冠状动脉CT血管造影(CTA)改变是否存在差异,探讨SMI患者动态心电图改变与冠状动脉CTA改变的关系。方法:利用12导联动态心电图筛选出SMI患者进行冠状动脉CTA检查,同时对无SMI但存在多重冠心病危险因素的患者进行冠状动脉CTA检查,作为对照组,对二者的结果进行对比分析。结果:随着心肌缺血负荷值的增加,冠状动脉CTA改变程度加重,无SMI患者冠状动脉CTA阳性率较SMI患者明显较低。结论:SMI患者动态心电图改变与冠状动脉CTA改变有显著的相关性。     

Silent diabetic nephropathy

AIM: To examine the risk of renal events in patients with biopsy-proven diabetic nephropathy (DN) and its possible associated factors.METHODS: Clinical and histological data of 60 patients diagnosed with diabetic nephropathy were retrospectively collected. Patients with evidence or suspicion of other nephropathies were excluded from the study. The final event was defined as renal replacement therapy (RRT) initiation or progression of chronic kidney disease (CKD), according to the KDIGO 2012 definition of a decrease in CKD category and a decrease in GFR of 25% or more.RESULTS: A total of 45 patients with a follow-up of at least 3 mo were included. Most of the patients presented type 2 DM, with a mean age of 58.3 years old. The time of evolution of DM was 9.6 ± 7.8 years, although in 13 patients, it was less than 5 years. A total of 62% of patients reached the final event in a median period of 3.4 years (95%CI: 2.1-4.7), with 21 of them requiring dialysis. The factors that were independently associated with renal survival were estimated glomerular filtration rate (eGFR) at the time of biopsy, cardiovascular disease (CVD) history and HbA1c less than 7%. Therefore, for each 10 mL/min per 1.73 m² reduction in eGFR, we obtained a DN progression risk of HR = 2 (1.3-3.0) (P = 0.001); patients with CVD were at greater risk for DN progression (HR = 2.8, 1.1-7.1, P = 0.032), and CKD patients with HbA1c < 7% demonstrated greater renal risk than patients with HbA1c ≥ 7%, with an HR of 2.9 (1.0-8.4) (P = 0.054).CONCLUSION: A past history of CVD is a risk factor for DN progression. Levels of HbA1c less than 7% could favor an eGFR decrease in these patients.     

动态心电图评价无症状性心肌缺血的价值

目的 探讨动态心电图（DCG）评价无症状性心肌缺血（SMI）的临床意义.方法 采用12导联DCG对2009年1月-2010年1月间在我院诊疗的冠心病患者60例进行检测,分析检测结果.结果 60例冠心病者检出缺血型ST-T变化者53例（88.33%）,共155阵次.属SMI者115阵次（74.19%）,有症状40阵次（25.81%）.115阵次SMI中66阵次（57.39%）与轻微的体力劳动或脑力活动因素有关,49阵次在安静时出现（42.61%）.115阵次SMI中在6：00～12：00发生者占42.61%,0：00～6：00发生者占12.17%,两者比较,差异具有统计学意义（P〈0.05）. SMI患者的ST段压低幅度、缺血持续时间与有症状心肌缺血患者比较差异无统计学意义（P〉0.05）.结论 动态心电图评价无症状性心肌缺血的临床意义重大,值得应用.