Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “TREMOR”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources
PubMed1998

Trimethoprim/sulfamethoxazole-induced tremor in a patient with AIDS.

OBJECTIVE: To report a case of trimethoprim/sulfamethoxazole (TMP/SMX)-induced tremor responsive to a reduction in dosage. CASE SUMMARY: A 55-year-old white man with AIDS and Pneumocystis carinii pneumonia (PCP) developed a tremor after receiving 5 days of therapy with TMP/SMX 19.4 mg/kg/d (TMP). The tremor resolved completely 3 days after a dosage reduction to TMP/SMX 15.1 mg/kg/d. DISCUSSION: Central nervous system adverse reactions to TMP/SMX have been reported in both the AIDS and non-AIDS populations. To our knowledge, this is the first reported case of TMP/SMX-induced tremor responsive to a reduction in dosage. Pharmacokinetic and clinical data suggest a concentration-dependent etiology for various adverse effects, including tremor. The mechanism of the tremor is unknown; however, toxic metabolites of SMX and disruptions of biogenic amine neurotransmission by TMP have been hypothesized. CONCLUSIONS: TMP/SMX remains the drug of first choice for treating PCP, but it is clearly not well tolerated by patients with AIDS. Concentration-dependent toxicities such as tremor may lead to premature discontinuation of proven, effective TMP/SMX therapy. Using the lower end of the recommended dosing range for TMP/SMX (TMP 15 mg/kg/d) may reduce the incidence of these toxicities while still achieving acceptable TMP concentrations and antimicrobial efficacy.

AIDS-Related Opportunistic Infections↗
PubMed1994

The influence of drinking on physiological tremor and reaction time.

Tremor is an invisible mechanical vibration observed on parts of the body. It is classified into physiological and pathological tremors. It was reported that an oral dose of alcohol could decrease the amplitude of pathological tremor. Usually, drunken level is estimated by the alcohol concentration in expiration. But, physiological tremor can be used to estimate drunken level easily. In this paper, power spectrum of the physiological tremor of index finger and some reaction time of the pedal operations of imitated car driving were measured every 15 minutes for 3 hours under drinking and non-drinking conditions. Subjects were 10 males aged 20 to 25 years. Under drinking condition, the total power values of tremor from 15 to 180 minutes after drinking were smaller than that of before drinking. It is clear that the influence of drinking could be estimated by the total power of the physiological tremor, even when the significant difference of the influence of drinking on reaction time was not found.

Adult↗
PubMed2000

Physiological tremor: does handedness make a difference?

The purpose of this study was to quantify with precision the characteristics of normal physiological tremor in the dominant and nondominant hand of a group of right-handed females. Twenty-two right-handed females (aged 20 to 40) gave informed consent to participate. Manual dominance determined with a questionnaire had to be equal to, or above 90%, for subjects to be accepted in the study. While the subjects kept their eyes closed, tremor was recorded simultaneously in the two extended index fingers during 40 s. Preceding the recording of postural tremor there was a period during which the subjects were asked to relax (control condition); to exert a pressure with the two index fingers on two strain gauges (static condition); or to press on and off with both index fingers on two strain gauges (dynamic condition). Each condition was recorded twice with two helium neon velocity lasers. This procedure was repeated after permutation of the lasers, thus a total of twelve sweeps of data were recorded. Seven parameters were used to analyze the tremor signal including measures of harmonicity, median frequency, proportional power in the 7-12 Hz range, amplitude, waveform morphology, entropy, and nonlinearity. Significant differences between hands were found in three parameters (median frequency, power in 7-12 Hz and entropy) but not in tremor amplitude (RMS). In addition, significant differences were found in five out of seven characteristics between conditions. These results suggest that neuromotor activity preceding the recording of tremor has a significant influence on tremor characteristics and that some of these characteristics are significantly different between the right and left hand in right-handed females.

Adult↗
PubMedDate not supplied

A new method for the measurement of tremor at rest.

This paper establishes a standard method for measuring human tremor. The electronic instrument described is an application of this method. It solves the need for an effective and simple tremor-measuring instrument fit for wide distribution. This instrument consists of a piezoelectric accelerometer connected to an electronic circuit and to an LCD display. The signal is also analysed by a computer after accelerometer analogic/digital conversion in order to test the method. The tremor of 1079 healthy subjects was studied. Spectral analysis showed frequency peaks between 5.85 and 8.80 Hz. Chronic cigarette-smoking and coffee drinking did not modify the tremor as compared with controls. Relaxation session decreased tremor significantly in healthy subjects (P less than 0.01). This new tremor-measuring method opens new horizons in the understanding of physiological and pathological tremor, stress, anxiety and in the means to avoid or compensate them.

Adult↗
PubMed2006

Unilateral Holmes tremor, clearly responsive to cerebrospinal fluid release, in a patient with an ischemic midbrain lesion and associated chronic hydrocephalic ventricle enlargement. Case report.

The authors describe a 58-year-old man with sudden onset of a unilateral tremor caused by a midbrain lesion that affected the substantia nigra and the cerebellothalamic pathway. There were also clinical and neuroimaging signs of a communicating chronic hydrocephalus. The patient was severely handicapped by this tremor, which was a typical Holmes tremor with rest, posture, and intention components. Parkinson disease or multiple-system atrophy as causes for the tremor could be ruled out by DaTSCAN and 123I iodobenzamide and single-photon emission computerized tomography (SPECT), respectively. The tremor was completely supressed by temporary and permanent cerebrospinal fluid release after ventriculoperitoneal shunt placement, without any additional medication, for a period of 6 months. Afterward, the tremor returned, and the patient had to be treated by a stereotactic electrode implantation in the contralateral ventralis intermedius nucleus, which led to complete tremor suppression during the 1.5-year follow-up period. In this case report, the authors present the clinical description and the electrophysiological, SPECT, and magnetic resonance imaging data of a rare combination of symptoms and their surgical treatment.

Brain Ischemia↗
PubMed2000

[Pharmacological treatment of parkinsonian tremor].

Tremor is the most common initial symptom and one of the cardinal features of Parkinson's disease. Mild tremor causes only minimal disability, but severe tremor causes more significant disability and distress for the patient than rigidity and/or bradykinesia. Anticholinergic agents, levodopa/DCI and dopamine agonists are most common and beneficial in parkinsonian tremor, but efficacies of these medications are variable among patients. Rigidity and bradykinesia are more responsive to levodopa/DCI therapy than tremor. Clozapine is an atypical neuroleptic agent, not on the market in Japan, and has been reported to decrease or ameliorate parkinsonian tremor through the studies of open label and double blind crossover as a new drug for parkinsonian tremor.

Adrenergic beta-Antagonists↗
PubMed1975

Nicotine induced tremor and antidiuresis and brain nicotine levels in the rat.

Injection of rats with 14C-labelled nicotine (3 mg/kg sc) resulted in tremor measured by an electronic device during the first minutes after the injection. The animals were decapitated immediately afterwards and tissue was removed for the measurement of nicotine and cotinine. In another set of experiments nicotine (2 mg/kg sc) was injected into alcohol anaesthetized rats, their urinary excretion was measured up to 40 min, and they were decapitated as above. Pretreatment with mecamylamine prevented nicotine-induced tremor and antidiuresis. It also lowered the brain and blood nicotine levels in tremor experiments but not in antidiuresis experiments. Restoration of tremor by arecoline did not modify the mecamylamine effects on the nicotine levels. The 2 mg/kg sc nicotine dose did not produce tremor although the brain nicotine levels at 10 min exceeded those measured at 2 min after 3 mg/kg of nicotine. It is concluded that the rate of receptor occupation is important in the nicotine tremor. Both tremor and antidiuresis correlate fairly well with brain nicotine levels whereas mecamylamine-nicotine antagonism is less clearly reflected in brain nicotine levels.

Animals↗
PubMed1975

Evaluation of skeletal muscle tremor due to bronchodilator agents.

Two methods of measuring skeletal muscle tremor when evaluating this side-effect of treatment with bronchodilator agents are described. The first method, involving drawing a line between two sinus curves, is simple and requires no special equipment. Each time that the line crosses one of the sinus curves this is registered as an error. The large variation in results is a disadvantage but this drawing method can be used when more sophisticated devices are not available. Skeletal muscle tremor recorded with a Grass accelerometer gives accurate results provided the method is carefully standardized and the resting period adequate. The dose-response curves obtained during infusions of beta-adrenergic-stimulating drugs are linearly related to the dose given and are highly reproducible. The tremor ratio has the advantage over absolute values of smaller variations. The first of three 30-s periods registered gives the lowest tremor value and least variation, so this is the period used for analysis. Subjective experience of tremor is related to the Grass recording. In some cases, however, there is marked discrepancy between subjective and objective evaluation of tremor, which may be explained by the masking effect of concomitant heart stimulation. When tremor is related to heart rate in a single experiment a regression line is obtained. Another drug may give a different slope. The two slopes demonstrate the different selectivity of the drugs for the beta-receptors in the heart and skeletal muscle.

Adult↗
PubMed2001

Motoneuron activity in patients with different types of tremor.

The aim of this work was to examine the segmental motoneuron activity as a possible mechanism of tremor generation. Eighty-three patients with different types of tremor (25 with Parkinsonian, 29 with essential, and 30 with enhanced physiological tremor due to anxiety), 25 Parkinsonian patients without tremor and 30 healthy volunteers were examined. The tremor was studied clinically and by electromyography in all limb positions. The F wave was examined for assessment of motoneuron activity. The wave was recorded after stimulation of the ulnar, median, tibial and fibular nerves. The maximal and mean F wave amplitudes, frequency of occurrence and number of phases were increased, and the duration was prolonged in all group of patients as compared to the healthy persons. The maximal and the mean F/M amplitude ratios, as well as the Fmean./Fmax amplitude ratio were increased in all groups of patients. All F wave parameters were most altered in Parkinsonian tremor patients followed by patients with rigidity. In conclusion increased motoneuron activity participates in generation of different types of tremor and in Parkinsonian rigidity.

Aged↗
PubMed1975

[Tremor following intracerebral carbachol injection. 1.Carbachol sensitivity of various brain structures].

Tremor produced by intracerebral injection of carbachol. I. Susceptibility of different brain areas to carbachol Microinjections of carbachol into the lateral ventricle of rats caused tremor depending on dose. Intensity and duration of motor effects after injection of carbachol (30 mug/3 mul bilateral) into different brain areas were found to depend on localization: strongest tremor was elicited by injections into the nucleus caudatoputamen and cortex cerebri, moderate tremor by administration into the substantia nigra reticularis, globus pallidus and thalamic brain regions. Target areas of mean sensitivity were demonstrated in more rostral and caudal parts of the formatio reticularis. The injection of carbachol into the nucleus ruber, nucleus linearis and substantia nigra compacta brought about lowest tremor values. Ablation of the site of injection from the remaining brain abolished tremor induced by carbachol contrary to the tremor induced by oxotremorine.

Animals↗
PubMed2002

[Characterization and discrimination of kinetic tremor in Parkinson's disease].

Kinetic tremor recorded with a laser system during a compensatory tracking task of the index finger was analyzed in 21 patients with PD whose tremor amplitude was between low and moderate, and 30 control subjects. Nine characteristics quantifying the tracking task and tremor including mean tracking error, reaction time, peakedness, harmonicity, median frequency, proportional power in the 3-4 Hz, 4-6 Hz and 7-12 Hz ranges, and power at 0.25 Hz, were applied to the processed signal. The discriminating power of each characteristic was evaluated using differences between group means (p values), maximum percentage discrimination, and number of outliers in the patient group using z-score and 96.7(th) percentile of the control group. All nine characteristics showed significant differences between means of the two groups using Welch-modified t-tests for unequal variances. The most discriminating characteristics reflected differences in the frequency distribution of the movement and did not correlate highly with postural tremor amplitude nor with clinical ratings of tremor. Discrimination methods classified correctly up to 66.7 p.cent of the patients. Combining representative information about proportional power during posture and tracking gave a much higher discrimination (90 p.cent) with respect to the 96.7th percentile of the control group. These results suggest that by combining information coming from postural and kinetic tremors it is possible to isolate a specific aspect of PD symptomatology which could be used to reevaluate the classic distinction made between the akineto-rigid and tremulous forms of PD independently of tremor amplitude.

Female↗
PubMed2003

[Effect of zonisamide on resting tremor resistant to antiparkinsonian medication].

The antiparkinsonian effect of zonisamide (ZNS), an antiepileptic agent, has been reported. Generally, resting tremor of patients with Parkinson's disease is not the main therapeutic target in this disease. However, depending on the social situation of the patient, the amelioration of the tremor may be necessary. In this study, we examined the effect of ZNS on tremor in nine patients who desired amelioration of their tremor. Except for tremor, they seemed to be under optimal therapeutic condition based on their daily activities. By the add-on administration of ZNS, the degree of tremor was reduced in seven out of nine patients (p < 0.0017). Although one patient felt sleepiness and two patients had a transient loss of appetite, all the patients tolerated the eight-week ZNS administration period. The final dose of ZNS was 100 mg/day in the majority of the patients. Although the mechanism of the antitremulous effect of ZNS is not yet clear, other than the enhancement of dopaminergic transmission, some specific action of the drug on tremor may exist. A more detailed random examination should be carried out.

Aged↗
PubMed2003

Dystonic tremor.

Dystonic tremor is a new and still poorly defined clinical entity. It seems to be generally accepted that tremor in the setting of obvious dystonia should be classified in this category. It may occur in generalized, segmental, and focal dystonias as well as in primary and secondary dystonias. In primary dystonia dystonic tremor may precede the occurrence of clear signs of dystonia which hence causes uncertainty about the classification of this condition. Secondary criteria like persistently focal tremor in one extremity, jerky and irregular tremors, gestes antagonistes, or selective responsiveness to antidystonic therapeutic agents may be helpful to distinguish this entity. The occurrence of dystonic tremor in symptomatic cases is often seen following thalamic lesions, peripheral injuries or in dystonia associated with sympathetic reflex dystrophy. The pathophysiology is unknown. Reciprocal inhibition and other inhibitory reflex pathways at various levels seem to be reduced at least in some cases with dystonic tremors.

Dystonia↗
PubMed1992

The effect of arm exercise and ocular massage on postural hand tremor.

In this pilot study, the effect of exertion on hand tremor was investigated. Postural head tremor was measured in eight ophthalmology residents before and after lifting a barbell and before and after massaging a phantom eye. All subjects showed an increase in postural hand tremor after lifting a barbell for five minutes (mean, 79% +/- 59%). Postural hand tremor increased 38% +/- 79% after ocular massage, which was not statistically significant (P greater than .5). The peak pressures generated during ocular massage ranged from 25 to 265 mmHg (mean, 134 +/- 80.4 mmHg). There was also no correlation between change in postural hand tremor and the pressure generated by ocular massage (P greater than .2). The authors conclude that strenuous arm exercise, such as lifting a barbell, increases postural hand tremor and should be avoided before doing microsurgery; ocular massage is not sufficient exercise to affect postural hand tremor adversely.

Arm↗
PubMed1978

Modifications of ongoing tremors and locomotion by sensory feedback.

In principle tremors can be produced by (1) mechanical oscillators (combination of masses and springs), (2) reflex oscillators arising from sensory feedback pathways, or (3) central oscillators generated by single "pacemaker" neurones or interconnected networks. Recent studies supporting each of these mechanisms under certain conditions are discussed. Differences between these mechanisms are clarified by recent studies in Edmonton on the premammillary cat. This preparation shows a prominent reflexly-induced tremor which can be modified by mechanical loading and electrical stimulation. It also shows spontaneous stepping on a treadmill which is known to be produced by a spinal "stepping generator", but can be modified in interesting ways by sensory perturbations. The applicability of these animal studies to human tremors is considered in relation to preliminary studies in Calgary on patients with Parkinson's disease or essential tremor. We have attempted to modify these tremors by application of torque pulses applied to the wrist. The results are described in terms of a normalized "resetting" index which has a high value (greater than 0.6) for all essential tremor patients studied, and a wide range of values for different parkinsonian patients. The resetting index may be useful in determining the relative importance of peripheral and central factors in producing tremor in a variety of patients.

Animals↗
PubMed1986

Tremor: a clinical and pharmacological survey.

Tremor may be defined as a rhythmic oscillation of a body part. In several neurologic disorders tremor appears as one of the symptoms, and may also be the main semeiological feature. No single structure involvement can be proven to be associated with tremor: it may be observed, in fact, in central as well as in peripheral diseases and in genetic or acquired disorders. The most useful semeiological classification divides the tremors in resting, postural and kinetic tremor, but only a complete anamnestic, clinical and electrophysiological evaluation permits to define the tremor and to achieve the correct diagnosis of a disease in which the symptom tremor is present.

Brain Neoplasms↗
PubMed1973

The nature of essential tremor.

The literature concerning essential tremor is confusing. Some accounts describe tremor of a resting type and its accompaniment by other neurological abnormalities. Critical analysis of the pertinent literature leaves some question as to the validity of these observations.Clinical analysis of 34 patients with essential tremor, personally observed during a four-year period, reveals this to be a monosymptomatic condition. The tremor was usually of both a postural and action type and resting tremor was not observed. There were no other neurological abnormalities. Serious disability was infrequent and, when present, was related to upper limb tremor. Essential tremor should be readily distinguishable from other central nervous system diseases but it may be confused with Parkinson's disease or cerebellar ataxia.

Adolescent↗
PubMed1983

Beta 1 versus nonselective blockade in therapy of essential tremor.

The beta 1-selective blocker metoprolol was compared to propranolol and a placebo in a double-blind crossover trial in 24 patients with essential tremor. Both beta blockers suppressed the essential tremor, but metoprolol, which caused a mean reduction of 32.0% in tremor intensity from the base-line value, was less effective than propranolol, which reduced mean tremor intensity by 41.3%. Subjective benefit for their tremor was found by 15 of the patients taking propranolol and by one taking metoprolol. The tremor frequency was not affected. No serious side effects were observed. Metoprolol may offer an alternative for those essential tremor patients who cannot tolerate propranolol.

Adult↗