Magnetic resonance-guided focused ultrasound for essential tremor:a prospective,single center,single-arm study

The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor.In 2018,the first magnetic resonance-guided focused ultrasound system in Chinese mainland was installed at the First Medical Center of the PLA General Hospital.This prospective,single center,open-label,single-arm study was part of a worldwide prospective multicenter clinical trial(ClinicalTrials.gov Identifier:NCT03253991)conducted to confirm the safety and efficacy of magnetic resonance-guided focused ultrasound for treating essential tremor in the local population.From 2019 to 2020,10 patients with medication refractory essential tremor were recruited into this open-label,single arm study.The treatment efficacy was determined using the Clinical Rating Scale for Tremor.Safety was evaluated according to the incidence and severity of adverse events.All of the subjects underwent a unilateral thalamotomy targeting the ventral intermediate nucleus.At the baseline assessment,the estimated marginal mean of the Clinical Rating Scale for Tremor total score was 58.3±3.6,and this improved after treatment to 23.1±6.4 at a 12-month follow-up assessment.A total of 50 adverse events were recorded,and 2 were defined as serious.The most common intraoperative adverse events were nausea and headache.The most frequent postoperative adverse events were paresthesia and equilibrium disorder.Most of the adverse events were mild and usually disappeared within a few days.Our findings suggest that magnetic resonance-guided focused ultrasound for the treatment of essential tremor is effective,with a good safety profile,for patients in Chinese mainland.

Assistive techniques and their added value for tremor classification in multiple sclerosis

Tremor occurs in about half of multiple sclerosis(MS)patients.MS tremor has a broad frequency range of 2.5-7 Hz,with a higher prevalence of postural tremor(44%)compared to intentional tremor(6%)(Alusi et al.,2001).Tremor may affect the upper and lower extremities,head,and trunk,and may even affect the vocal cords in isolated cases of palatal tremor.MS tremor is classically attributed to lesions of the brain stem,cerebellum,or cerebellar peduncles,and tremor intensity has been shown to correlate with the number of lesions or their functional connections.However,recent work has demonstrated that inflammatory damage to the cerebello-thalamic and cortico-thalamic pathways might also play an important role in causing tremor,as it co-occurs with other signs and symptoms of MS such as dysarthria,dysmetria,dysdiadochokinesia,and dystonia(Alusi et al.,2001).

Quantifying Kinematic Tremor in an NGLY1-Deficient Individual: A Case Study

NGLY1 Deficiency is an autosomal recessive congenital disorder that has been identified in less than 100 individuals. Most individuals with NGLY1 Deficiency display hyperkinetic movement disorders, including choreiform, athetoid, dystonic myoclonic, dyskinetic, and dysmetric movements. Developing a consistent and concise consensus on the classification and evaluation of tremors is essential to forward the research and treatment of tremors. It has also been reported that some individuals with NGLY1 Deficiency demonstrate tremor, but such tremor has never been formally investigated. The primary objective of this study is to determine if an individual with NGLY1 Deficiency demonstrates an identifiable tremor during a series of arm movements and, if so, describe the frequency and power characteristics of that tremor. Arm movement kinematics were obtained using a 16-camera Vicon system, and time series trajectory waveforms for three planes of a marker placed on the hand were developed. Custom MATLAB scripts were utilized to compute Fast Fourier Transformations of the data within the identified waveform segments. A mean frequency of 2.30 Hz (SD = 1.05) with a mean power of 5.02 |P1(f)| (SD = 4.63) suggests that our participant’s kinematic data did display a persistent tremor in both hands across all tasks and movement planes. Analyses of the reaching hand and the non-reaching hand suggest the participant displayed an action tremor in both postural and intention (kinetic) tremors. Future directions should include assessing additional individuals with NGLY1 Deficiency to determine if the tremor is a distinguishable disorder behavior. Additionally, evaluating other anatomical sites, such as the elbow, head, and lower limbs, would provide further insights into the characteristics of this tremor.

Essential tremor:A three-dimensional neurosphere in vitro model to assess the neurotoxicity of harmane

Objectives: To use a novel in vitro model of three-dimensional(3D) neurosphere cultures to assess neurotoxic or neuroprotective effects with harmane as a model compound.Methods: A reproducible model of 3D spheroids was developed from embryonic mouse cortical neurons,using molded agarose micro-wells;this method seems particularly practical as it is customizable and widely available and does not require specific cell treatments or assay components different from 2D cultures, allowing for the easy transposition of routine protocols. To assess the neurotoxic effects of harmane, a resazurin assay was performed to measure cell viability, and a highly sensitive fluorometric method, based on the oxidation of dichlorodihydrofluorescein, was applied to measure eventually induced reactive oxygen species(ROS) after exposure to harmane at increasing concentrations of 50 100,and 250 μm.Results: Hydrogel microwells facilitated the assembly of spheroids containing neurons and glial cells into a complex 3D structure and prevented the agglomeration of spheroids. Exposure to harmane induced cytotoxicity in 3D neural spheroids, which was correlated with harmane concentrations, with a 27%reduction in viability at 250 μm. Harmane that did not induce significant levels of oxidative stress was detected for all tested concentrations.Conclusion: This 3D neurosphere model mimics a neuronal microenvironment, allowing a fine study of neurodegenerative disorders and the effects of chemicals on the brain. This model opens novel opportunities, not only from a pathogenetic point of view but also from a therapeutic perspective.

HPLC法测定tremor大鼠脑组织中谷氨酸和GABA含量

目的建立测定tremor大鼠(tm)脑内海马组织中GLU及GABA浓度的高效液相色谱(HPLC)方法。方法冰上剥离13wk的tm/Wistar大鼠海马组织,低温匀浆处理,利用邻苯二甲醛(OPA)柱前衍生HPLC法结合荧光检测器测定GLU和GABA的含量。0.1mol·L-1醋酸钾和甲醇进行二元梯度洗脱,峰面积定量。结果GLU的线性方程为Y^=1E+06X(r2=0.9937),线性范围为0.15～5.88mg·L-1,具有良好的线性关系,在0.74、1.47、3.68mg.L-13个浓度下样本回收率分别为97.7%、98.9%、100.5%;样品中GLU日内变异系数为3.8%,隔日测定后,日间变异系数为5.9%;GABA的线性方程为Y^=4E+06X(r2=0.998),线性范围为0.10～2.15mg·L-1,具有良好的线性关系,在0.2、0.5、1.0mg·L-13个浓度下样本回收率分别为98.3%、101.0%、102.7%;样品GABA日内变异系数为2.3%,隔日测定后,日间变异系数为3.9%。结论该方法较简便、快速且干扰相对较小,满足测定要求,可用于氨基酸的含量测定研究。

4D printing of soft orthoses for tremor suppression

Tremor is an involuntary and oscillatory movement disorder that makes daily activities difficult for affected patients. Hand tremor-suppression orthoses are noninvasive, wearable devices designed to mitigate tremors. Various studies have shown that these devices are effective, economical, and safe;however, they have drawbacks such as large weight, awkward shape, and rigid parts. This study investigates different types of tremor-suppression orthoses and discusses their efficiency, mechanism,benefits, and disadvantages. First, various orthoses(with passive, semi-active, and active mechanisms) are described in detail.Next, we look at how additive manufacturing(AM) has progressed recently in making sensors and actuators for application in tremor orthoses. Then, the materials used in AM are further analyzed. It is found that traditional manufacturing problems can be solved with the help of AM techniques, like making orthoses that are affordable, lighter, and more customizable. Another concept being discussed is using smart materials and AM methods, such as four-dimensional(4D) printing, to make orthoses that are more comfortable and efficient.

Joint observation of long period tremor signals with broadband seismometer,tiltmeter and gravimeter

We report here the observation result of joint observation of long period tremor signals with broadband seismome-ter,tiltmeter and gravimeter at the HUST(Huazhong University of Science and Technology)station.The observed data were compared and analyzed.Since 2005,the several tens of abnormal tremor signals which are weak,com-plex and duration of 2 to 3 days have been synchronously recorded by the different instruments.The tremor signals have the periodic domain in the range of 3 to 5 minutes,20 to 30 minutes and even more than 1 hour.The observa-tion shows such tremors are a physical existence.The analysis indicates that a part of the tremors caused by the typhoon from the western Pacific Ocean.These tremors have a close relationship with wind velocity of typhoon and distance between the typhoon center and the station.Except these,the cause of others is still unclear.

Tremor大鼠皮质内ERK信号通路相关蛋白表达的变化

目的研究ERK!信号通路相关蛋白在癫痫状态下的改变,以探讨ERK信号转导通路在癫痫发病机制中的作用。方法实验分为两组,分别为Tremor大鼠组和Wistar大鼠组。通过Western Blot方法检测两组大脑皮质内ERK蛋白和p-ERK蛋白含量的异常变化。结果通过PCR鉴定了Tremor大鼠,试验分为Tremor组(实验组)和Wistar组(对照组)。利用western Blot方法测定ERK1/2和p-ERK1/2蛋白在Tremor大鼠和Wistar大鼠的皮质中均有表达,Tremor大鼠的ERK1/2和p-ERK的蛋白含量分别为0.140 3和0.734 4,Wistar组大鼠的ERK1/2和p-ERK的蛋白含量分别为0.170 9和0.975 4。结论 ERK1/2和p-ERK蛋白在癫痫大鼠皮质内的表达显著减少,说明ERK信号通路在癫痫状态下被抑制。

Gas-dynamic phenomena caused by rock mass tremors and rock bursts

Similar to coal, rock and gas ejections, rock mass tremors and rock bursts are among the most serious natural hazards accompanying the underground extraction of coal. Gas-dynamic phenomena caused by rock mass tremors and rock bursts observed as transient states of air parameters in mining headings,are usually generated as a result of a change in the geometry of headings and the release of considerable amounts of gases. Particular significance is attributed to transient states caused by disasters, which are often accompanied by rapid incidents, presenting threats to the life and health of the underground crew.In Polish mining there are known examples of transient states of air parameters recorded during gasdynamic phenomena, e.g. tremors and rock bursts. The paper presents the case studies of rapid seismic incidents to show how records in mine monitoring systems broaden the knowledge about the transient states of air parameters in mining headings generated because of them.

Neural computational modeling reveals a major role of corticospinal gating of central oscillations in the generation of essential tremor

Essential tremor, also referred to as familial tremor, is an autosomal dominant genetic disease and the most common movement disorder. It typically involves a postural and motor tremor of the hands, head or other part of the body. Essential tremor is driven by a central oscillation signal in the brain. However, the corticospinal mechanisms involved in the generation of essential tremor are unclear. Therefore, in this study, we used a neural computational model that includes both monosynaptic and multisynaptic corticospinal pathways interacting with a propriospinal neuronal network. A virtual arm model is driven by the central oscillation signal to simulate tremor activity behavior. Cortical descending commands are classified as alpha or gamma through monosynaptic or multisynaptic corticospinal pathways, which converge respectively on alpha or gamma motoneurons in the spinal cord. Several scenarios are evaluated based on the central oscillation signal passing down to the spinal motoneurons via each descending pathway. The simulated behaviors are compared with clinical essential tremor characteristics to identify the corticospinal pathways responsible for transmitting the central oscillation signal. A propriospinal neuron with strong cortical inhibition performs a gating function in the generation of essential tremor. Our results indicate that the propriospinal neuronal network is essential for relaying the central oscillation signal and the production of essential tremor.

Anomalous tremor before 2008 Ms8.0 Wenchuan earthquake: a review

In this paper we give a review of several previously published papers on anomalous tremors observed before the 2008 Ms8.0 Weuchuan earthquake. Based on the observed time and frequency shifts between coastal and inland stations, we discussed some methods to distinguish different kinds of microseisms, and speculated that a pre-earthquake typhoon might have caused a ＂mainland-originated microseism＂ which in turn trig- gered the earthquake.

Wireless accelerometer configuration for monitoring Parkinson’s disease hand tremor

Parkinson’s disease is neurodegenerative in nature and associated with characteristic movement disorders, such as hand tremor. Wireless accelerometer applications may advance the quality of care for Parkinson’s disease patients. The acceleration waveform of the respective hand tremor can be recorded and stored for post-processing and progressive status tracking. A wireless accelerometer configuration for monitoring Parkinson’s disease hand tremor is presented. The proposed configuration is envisioned to be conducted with the assistance of a caregiver. For initial engineering proof of concept simulated Parkinson’s disease tremor is recorded through a wireless accelerometer node and contrasted to a statically positioned and tandem activated wireless accelerometer node. Statistical significance is acquired regarding the quantification of the simulated Parkinson’s disease tremor acceleration waveform and statically positioned acceleration waveform, while demonstrating a considerable degree of accuracy, consistency, and reliability.

Understanding Tremor in Rapid Upper Limb Movements Using 3D Accelerometers Data

Tremor is a manifestation of a variety of human neurodegenerative diseases, notably Parkinson’s disease (PD) and Essential Tremor (ET), both affecting millions worldwide. PD is primarily caused by a progressive loss of dopamine neurons in the nigrostriatal system that leads to widespread motor symptoms such as bradykinesia, rigidity, tremor and postural instability. ET typically involves a tremor of the arms, hands or fingers. No definitive test or biomarker is yet available for PD or ET, so the rate of misdiagnosis is relatively high. As tremor is a very common feature at the onset of both diseases, it is crucial to be able to characterize it. This is made possible using acce?lerometers to quantify the tremor amplitude and frequency. In this work we aim to find tasks involving upper limb movements that are suitable to modulate both types of tremor. Four tasks were tested, differing on whether the arms moved together or alternatingly and whether loads were added. Significant differences in tremor measures were found when patients were asked to perform simultaneous rapid arms movements with loads placed on their wrists. These results may allow the design of an efficient fMRI protocol for identifying the cortical circuits responsible for the modulation of tremor.

A Smart Wearable Ring Device for Sensing Hand Tremor of Parkinson’s Patients

Parkinson’s disease(PD)is a very common neurodegenerative disease that occurs mostly in the elderly.There are many main clinical manifestations of PD,such as tremor,bradykinesia,muscle rigidity,etc.Based on the current research on PD,the accurate and convenient detection of early symptoms is the key to detect PD.With the development of microelectronic and sensor technology,it is much easier to measure the barely noticeable tremor in just one hand for the early detection of Parkinson’s disease.In this paper,we present a smart wearable device for detecting hand tremor,in which MPU6050(MIDI Processing Unit)consisting of a 3-axis gyroscope and a 3-axis accelerometer is used to collect acceleration and angular velocity of fingers.By analyzing the time of specific finger movements,we successfully recognized the tremor signals with high accuracy.Meanwhile,with Bluetooth 4.0(Bluetooth Low Energy,BLE)and networking terminal ability,tremor data can be transferred to a monitoring device in real time with extremely lowenergy consumption.The experimental results have shown that the proposed device(smart ring)is convenient for long-term tremor detection which is vital for early detection and treatment for Parkinson’s disease.

Voltage adjustment improves rigidity and tremor in Parkinson's disease patients receiving deep brain stimulation

Deep brain stimulation of the subthalamic nucleus is recognized as the most effective treatment for moderate and advanced Parkinson＇s disease. Programming of the stimulation parameters is important for maintaining the efficacy of deep brain stimulation. Voltage is consid- ered to be the most effective programming parameter. The present study is a retrospective analysis of six patients with Parkinson＇s disease （four men and two women, aged 37-65 years）, who underwent bilateral deep brain stimulation of the subthalamic nucleus at the First Affiliated Hospital of Sun Yat-sen University, China, and who subsequently adjusted only the stimulation voltage. We evaluated motor symptom severity using the Unified Parkinson＇s Disease Rating Scale Part III, symptom progression using the Hoehn and Yahr scale, and the levodopa equivalent daily dose, before surgery and 1 and 2 years after surgery. The 2-year follow-up results show that rigidity and tremor improved, and clinical symptoms were reduced, while pulse width was maintained at 60 ps and frequency at 130 Hz. Voltage adjust- ment alone is particularly suitable for patients who cannot tolerate multiparameter program adjustment. Levodopa equivalent daily dose was markedly reduced 1 and 2 years after surgery compared with baseline. Our results confirm that rigidity, tremor and bradykinesia can be best alleviated by voltage adjustment. The trial was registered at ClinicalTrials.gov （identifier： NCT01934881）.

Accuracy of forecast of mine tremors location

The Upper Silesian Coal Basin is one of the most active mining areas in the world in respect of seismicity. Underground mining in this area takes place in a special environment with a high degree of risk of unpredictable event occurrence. Especially dangerous are phenomena that occur during the extraction of deposits at great depths in the environment of compact rocks. Deep underground mining violates the balance of these rocks and induces dynamic phenomena at the longwall life （in terms of distance） referred to as mine tremors. The sources of these tremors are located in layers characterised by high strength, especially in thick sandstone strata occurring in the roof of the mined seam. In the paper a discussion is presented about the influence of mining intensity （longwall face speed） on the location of mine tremor sources, both in the direction of longwall life （in terms of distance） and towards the surface. The presented material has been prepared basing on the results of tests and measurements carded out at the Central Mining Institute.

Statistics of Seismic Tremors with Harmonic Overtones Recorded at Syowa Station, Antarctica: October 2014-March 2015

During the period from October 2014 to March 2015, a total number of 82 seismic tremors and 66 ice-quakes were identified in both three-component short-period seismographs (HES) and broadband seismographs (STS-1) at Syowa Station (SYO), Antarctica. Statistics of the number of these tremors indicated that many tremors were likely to occur when large increases in temperature and/or wind speed during the period. This implied that the rapid increase in temperature enhanced a melting speed of cryosphere environment with generating seismic energy;the tremors were also excited by stormy conditions, associated with interactive resonance between sea-ices and oceanic swells. The characteristic tremors of harmonic overtones with strong amplitudes were explained by repetitive sources, suggesting inter-glacial asperities such as the collision of icebergs and fast sea-ice, calving of glaciers/ice-streams at the coastal environment of Antarctica. These high amplitude tremors occurred independently from other majority types of events, characterized by non-linear, small amplitude and weak signals at the stormy condition and rapid increase in temperature.

Seismic Tremors and Their Relation to Cryosphere Dynamics in April 2015 around the Lützow-Holm Bay, East Antarctica

Characteristics and statistics of seismic tremors occurring during April 2015 were investigated by using short-period and broadband seismographs deployed at Syowa Station (SYO), in the Lützow-Holm Bay (LHB), East Antarctica. In order to examine a relationship between surface environments in particular cryosphere variation, the MODIS satellite images were utilized for comparison with the detected tremor events. Since a large volume of sea-ice was discharged during the April, together with several large icebergs passed through from the west to the east at northern edge of the fast sea-ice of LHB, it was expected to detect seismic tremors involving cryospehre dynamics. During the month, a total number of 49 tremor events including short duration ice shocks were identified. Majority of the events (N = 39) had their duration times more than 15 minutes, which were divided into both tremors and ice shocks on the basis of experienced definition at SYO. Cryospheric sources recorded by seismic tremors were classified into several origins (collision, calving, crevassing, crashing, etc.): “crevassing events” along the large cracks inside the fast sea-ice in LHB (04 April), “discharge events” of fast sea-ice from the Bay (07 April), “collision events” between iceberg and the edge of fast sea-ice (14 April), “crashing movement” between fragmentation of fast sea-ice and packed sea-ice (18 April), and other origins. In particular, strong amplitude tremors with harmonic overtones were assumed to be occurred independently from whether condition, because these overtone tremors were identified at less stormy days by comparison with infrasound data at SYO.

Functional magnetic resonance imaging of regional homogeneity changes in parkinsonian resting tremor

Regional homogeneity analysis of low-frequency blood oxygenation level-dependent signals from neighboring voxels enables the analysis of local neuronal synchrony. Both structural magnetic resonance imaging and resting-state functional magnetic resonance imaging scans were collected from nine Parkinson＇s disease patients with right resting tremor, and from eight age-matched normal controls. Regional homogeneity was compared between Parkinson＇s disease patients and controls. The results revealed that regional homogeneity was increased in several brain regions, including the right precuneus, right superior parietal gyrus, left anterior cingulate cortex, right middle frontal gyrus and right inferior frontal gyrus. Conversely, regional homogeneity was decreased in the cerebellar vermis in Parkinson＇s disease patients compared with healthy controls.

Tremor suppression in master-slave robot remote welding system

Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted of a master manipulator with six degree of freedom （ DOF ） , an industrial computer control system and a slave Motoman HP3 J robot, and human hand tremor and digital filtering were discussed. An optimal digital filter was designed to clean human tremor signal for improving the welding seam tracking precision. The experimental results show that the digital filter suppresses the operator＇ s tremor signal.