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[Juvenile Parkinson's disease initially presenting as bulbar incoordination: a case report].

We report a case of juvenile Parkinson's disease which initially presented as bulbar incoordination at the age 12. The condition was characterized by dystonia of the upper extremities. The patient was a 14-year-old female. The patient's main symptoms were bulbar dysfunction. Resting and action tremor, akinesia, stooped posture, distortion of the trunk, dystonia of the upper extremities, oculogyric crisis, and impairment of the postural reflex were seen. The bulbar symptoms were considered to be attributable to circumoral uncoordination. Although L-dopa decarboxylase inhibitors were markedly effective in alleviating these symptoms, an adverse reaction due to the agent was observed as the form of oral dyskinesia. Since the changes in blood concentration of L-dopa after administration of the agent was clearly reflected in the surface electromyogram, we concluded that this diagnostic procedure is useful in evaluating the therapeutic efficacy of L-dopa.

Adolescent↗

[Hereditary Parkinson disease: report of 3 families with dominant autosomal inheritance].

We have studied three families who ancestors immigrated to North America from contiguous regions of northern Germany and southern Denmark. The pedigrees contain 77,206 and 376 individuals spanning 6, 7 and 8 generations with 7,7 and 11 affected members, respectively. Autosomal dominant inheritance pattern is present in two families and probable in the third. Typical L-dopa-responsive parkinsonism with bradykinesia, rigidity, resting tremor, and impaired postural reflexes uniformly develop in affected individuals from all three families. Further research on these three families, including genetic, pathologic and clinical examinations is planned.

Adult↗

[The influence of experimental hemispherectomy and hemicerebellectomy on the acquisition and retention of habituation in pigeon].

The subject of investigation was the analysis of the acquisition and retention of the vestibular habituation in pigeons after hemispherectomy or hemicerebellectomy. The habituation training was performed using rotatory test. The frequency of head nystagmus and postural reflexes were examined before and after acquisition of habituation and some days later, for evaluation of retention. Our results suggests that hemispherectomy does not inhibit acquisition of habituation but retention of this phenomenon is shorter at that time. The hemicerebellectomy makes impossible the vestibular habituation.

Animals↗

Clinical analysis of Parkinson's disease treated by integration of traditional Chinese and western medicine.

Parkinson's discase is an extrapyramidal disease characterized by tremor, hypokinesis and postural reflex disturbance. It often occurs in the middle and the old-aged. People usually use synthetic drugs such as atropine, levodopa or medopa to gain temporary relief, but the side effects are serious. Along with prolongation of medication, the effective rate reduces step by step. Hence, seeking for a new therapy via the approach of integrating traditional Chinese and western medicine becomes a pressing issue. Since the early 1970's, the author has made use of Chinese herbal drugs, acupuncture and moxibustion as the main measures to treat this affection, and definite therapeutic effects have been obtained. Owing to the scarceness of data regarding syndrome differentiation and treatment of such illness in traditional Chinese medicine (TCM), the author puts forward some of her personal views in this aspect for colleagues' further discussion.

Adult↗

Pergolide mesylate in Parkinson's disease treatment.

In the past 15 years, clinical data of over 1,500 patients treated with pergolide mesylate have been published. Pergolide is a dopamine agonist with a potent stimulating effect on D2 and also on D1 receptors. This pharmacodynamic characteristic seems the most effective in increasing the motility in Parkinson's disease. Pergolide has been used almost exclusively as an adjunct to levodopa treatment. Its positive effects seems to be related to its long plasma half life, about 27 hours, and 5-6 hours of clinical activity; it has shown to be effective on all parkinsonian symptoms except for the reduction of postural reflexes, it reduces off periods and compared to bromocriptine, it considerably improves the activities of daily living. Adverse reactions are, for the most part, mild and reversible, they mostly include nausea and gastroenteric disturbances.

Antiparkinson Agents↗

[Concept and diagnostic criteria of Parkinson's disease and parkinsonism].

Parkinson's disease (PD) is defined as a neurodegenerative disorder characterized pathologically by degeneration of substantia nigra and locus coeruleus with Lewy bodies in the remaining neurons and clinically by resting tremor, cogwheel rigidity, bradykinesia and loss of postural reflex. Parkinsonism may be defined as those who show at lest two of the major four features characterizing PD. We propose the following diagnostic criteria for PD, i.e., clinical criteria (resting tremor or at least two of the remaining cardinal features of PD), treatment criteria (good response to anti-parkinson drugs), image criteria (essentially normal cerebral MRI), and exclusion criteria (no history of encephalitis or exposure to parkinsonism-inducing substances or drugs). Patients must fulfil all four criteria for the diagnosis.

Humans↗

[Central motor conduction time using magnetic and vibratory stimulation in Parkinson's disease, especially in patients with rigidity].

Rigidity, tremor, akinesia and disorder of postural reflex are the main clinical features of Parkinson's disease. We presented the mechanism underlying rigidity and assessed central motor conduction time (CMCT) using magnetic, with or without vibratory, stimulations. Basal ganglia, especially, the internal pallidum, and the thalamus play major roles in the mechanism of rigidity in Parkinson's disease. Hyperexcitability of the spinal motor nucleus due to low threshold has been recognized. Magnetic stimulation is painless and is simpler than electric stimulation. Therefore, this method is used clinically for evaluating conduction disturbance of the upper motor neurons in multiple sclerosis, cerebrovascular disease and so on. CMCT measured by magnetic and/or electric stimulation may be abbreviated or normal in Parkinson's disease, according to the literature, though controversy persists in this regard. In our study, CMCT was normal in Parkinson patients. However, CMCT was reduced in patients with rigidity and tremor. Furthermore, in a portion of the patients, CMCT was further abbreviated by also applying vibratory stimulation. These observations support the hypothesis that cells in the thalamus, cortex and spinal cord and/or pathways in these portions of the central nervous system are excitable or activated in Parkinson patients with rigidity and tremor. However, elucidation of the mechanisms underlying rigidity and tremor awaits further investigation.

Humans↗

Brain death.

Brain death occurs whenever there is involvement of higher centers such as Cerebral Cortex and Thalamus (unresponsiveness and deep coma) and Brainstem and Basal ganglionic structures (loss of spontaneous respiration all cranial nerve, and postural reflexes). Involvement of Spinal Cord is less constant. Drug intoxication should be excluded. An electroencephalogram may be done but what is paramount is the physician's clinical judgment. The medico-legal implications of brain death is less complicated than it is generally presumed to be. It is extablishment of the legality of brain death concept that is crucial. This allows the physician to use his judgment to implement the law.

Brain Death↗

[A 85-year-old woman with the onset of progressive gait disturbance at 80 years of the age].

We report a 85-year-old woman who had an onset of gait disturbance at 80 years of the age. She had a dizzy spell when she was 80-year-old. She was evaluated at another hospital where paroxysmal tachycardia and sinus arrest lasting as long as 5.8 seconds were found. She was diagnosed as having sick sinus syndrome and a pace maker was inserted. She had a gradual onset of disturbance of gait shortly after the above dizzy spell. She became unable to walk fast and her steps became small. Neurologic examination at age 83 revealed small step gait with freezing episodes. Retropulsion was present. No motor weakness or origidity was noted. She had no tremor. Mentally she was alert and sound. Cranial nerves were essentially normal. Cranial CT scan revealed slight diffuse low density change in the bilateral cerebral white matter. She was treated with amantadine HCI and levodopa with carbidopa. Her gait and balance showed some improvement. She developed pneumonia and worsening of her gait when she was 85 years of the age, and she was admitted again to our hospital. She was mentally alert and sound but she showed marked freezing of gait with loss of postural reflex; she would have fallen down unless supported upon standing. Cranial nerves were again essentially normal. Her hospital course was complicated by pneumonia, DIC, and renal failure. She expired suddenly on the 10th day of her last admission. She was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had vascular parkinsonism due to lacunar state. However, paucity of vascular changes in her CT scan remained as a question. Other participants thought that she had nigral cell loss secondary to her aging and circulatory disturbance which would have been caused by her sick sinus syndrome. Post-mortem examination revealed marked loss of nigral pigmented cells; the cell loss was diffusely seen in the substantia nigra. Neurofibrillary tangles were seen in the remaining neurons. In addition, gliosis was noted in the globus pallidus and the subthalamic nucleus, however, neuronal loss was very mild in those nuclei. In the superior colliculus, neuronal loss was mild, however, gliosis was seen. No clear neuronal loss was observed in the locus coeruleus, however, Lewy bodies were seen in the remaining neurons. Furthermore, Lewy bodies were also found in the substantia sigra. It was thought that she had progressive supranuclear play (PSP). Question was whether or not she was complicated by Parkinson's disease. Clinically, she had no rigidity or tremor. Pathologically, locus coeruleus did not show neuronal loss. Therefore, incidental Lewy body disease was raised as a possibility. Finally, it should be pointed out that she had no oculomotor disturbance or dementia, yet she had PSP. Her clinical features were those of pure akinesia. Pathologic changes were also relatively mild except for those in the substantia nigra. Possibility of post-encephalitic parkinsonism without encephalitis was also discussed, however, over all distribution of her pathologic changes was more consistent with PSP.

Aged↗

[A management for severe acquired stuttering in a case of pure akinesia syndrome].

We reported a 73-year-old man with pure akinesia syndrome who showed severe acquired stuttering and paradoxical kinesia on speech. He was evaluated in another hospital for bradykinesia and frozen gait at age of 67 when his cranial MRI disclosed ischemic changes in bilateral basal ganglia and periventricular deep white matter. The treatment with L-dopa and L-threo DOPS was not effective. His symptoms were slowly progressive and got worse gradually. At age of 72, he began to have difficulty in speech due to severe acquired stuttering, and one year later, he visited our hospital. The diagnosis of pure akinesia syndrome was made because of akinesia, micrographia, marked frozen gait with paradoxical kinesia and disturbance of postural reflex without tremor and rigidity. His speech showed severe acquired stuttering with marked blocking and repetition of initial phonemes at the beginning of speech. But intelligible speech recurred with pointing the characters by his finger or with writing an initial letter of word, although his speech was small and monotonous. Surface EMG findings of muscles participating speech in acquired stuttering showed the similar tonic discharge to those of muscles of lower extremity in frozen gait. These results implied that freezing phenomenon and festination of muscles participating speech in our patient may result in acquired stuttering.

Aged↗

[Tool for the quantitative evaluation of symptoms in defined idiopathic Parkinson's disease].

OBJECTIVE: To determine the reliability of a clinical quantitative instrument for assessing the symptoms of Defined Idiopathic Parkinson Disease (DIPD). PATIENTS AND METHODS: From 148 patients with parkinsonism syndrome, the best 62 EPID cases, according to Calne et al (1992), and Larsen et al (1994) criteria--37 males and 25 females--were selected. RESULTS: The age mean was 68.4 (7.4) year-old, the age of onset was 64 (7.2) years, the time of evolution was 4.3 (2.9) years. 98.4% of the sample was in 1 to 3 Hoehn and Yahr clinical state. Right parkinsonism score (RPS) was 8.2 (4.2), and left (LPS) was 6.7 (4.8). Significant differences between right and left tremor, rigidity and dyskinesia scores were found (ji-squared, p < 0.05). Total parkinsonism score (TPS) was 14 (6.9). Several significant and high correlated coefficients were found between most of the scale's components and Hoehn and Yahr clinical state, TPS, and time of evolution (r > 0.40, p < 0.0001). Total 21 items scale Cronbach's alpha coefficient was 0.92. A stepwise multiple regression model showed that rigidity, postural reflex disorder, and micrography were able to predict the Hoehn and Yahr clinical state (81.4%, p < 0.0001). A principal component analysis showed that akinesia explained more than 59% of the instrument variance, while micrography only explained 0.57% of the variance (100 time lesser). CONCLUSION: A reliability structure of the instrument was demonstrated for assessing parkinsonism symptoms in DIPD subjects.

Aged↗

Assessment of cardiovascular reflexes: influence of posture and period of preceding rest.

The aim of the present study was to investigate the effects of a pretest redistribution of blood volume and of a change in the neurohumoral condition on the blood pressure (BP) and heart rate (HR) responses to three commonly used cardiovascular reflex tests: standing up, forced breathing, and the Valsalva maneuver in 10 healthy male subjects. Base-line conditions were altered by changing posture and the duration of rest preceding the test stimulus. A continuous recording of finger BP was obtained noninvasively by a Finapres. The main observations from this study are with respect to standing up: lengthening the period of preceding rest from 1 to 20 min enlarges the initial BP (systolic/diastolic) decrease (from 8 +/- 10/9 +/- 4 to 27 +/- 8/19 +/- 4 mmHg, P less than 0.01) and the subsequent BP overshoot (from 17 +/- 10/12 +/- 7 to 31 +/- 10/18 +/- 7 mmHg, P less than 0.05); to forced breathing: inspiratory-expiratory changes in BP but not in HR are larger in the upright posture (P less than 0.05); and to the Valsalva maneuver: change in posture from supine to standing increases the phase II BP decrease (from 18 +/- 12/8 +/- 6 to 45 +/- 16/21 +/- 9 mmHg), phase IV systolic BP overshoot (from 26 +/- 16 to 71 +/- 17 mmHg), delta HRmax (from 30 +/- 10 to 47 +/- 12 beats/min), and the Valsalva ratio (HRmax/HRmin), from 2.0 +/- 0.3 to 2.6 +/- 0.7, all significant at P less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Effect of the cervical reflex on the posture of normal subjects. Balance measurement study].

The little we know about the existence and the meaning of the cervical component on the vestibulo-spinal reflex, led us to carry out a study on normal subjects examined by computerized stabilometry with the head turned 75 degrees left and right, in order to check the postural alterations during the stimulation of the neck proprioceptors. The results show a significant increase of the values of the LTT, SE and Vm with the head turned to the left; the increases were not significant with the head turned to the right. The difference is difficult to explain. The results show that in man too the posture is affected by reflex of cervical origin.

Adult↗

Adapting reflexes controlling the human posture.

Doubt about the role of stretch reflexes in movement and posture control has remained in part because the questions of reflex "usefulness" and the postural "set" have not been adequately considered in the design of experimental paradigms. The intent of this study was to discover the stabilizing role of stretch reflexes acting upon the ankle musculature while human subjects performed stance tasks requiring several different postural "sets". Task specific differences of reflex function were investigated by experiments in which the role of stretch reflexes to stabilize sway doing stance could be altered to be useful, of no use, or inappropriate. Because the system has available a number of alternate inputs to posture (e.g., vestibular and visual), stretch reflex responses were in themselves not necessary to prevent a loss of balance. Nevertheless, 5 out of 12 subjects in this study used long-latency (120 msec) stretch reflexes to help reduce postural sway. Following an unexpected change in the usefulness of stretch reflexes, the 5 subjects progressively altered reflex gain during the succeeding 3-5 trials. Adaptive changes in gain were always in the sense to reduce sway, and therefore could be attenuating or facilitating the reflex response. Comparing subjects using the reflex with those not during so, stretch reflex control resulted in less swaying when the task conditions were unchanging. However, the 5 subjects using reflex controls oftentimes swayed more during the first 3-5 trials after a change, when inappropriate responses were elicited. Four patients with clinically diagnosed cerebellar deficits were studied briefly. Among the stance tasks, their performance was similar to normal in some and significantly poorer in others. Their most significant deficit appeared to be the inability to adapt long-latency reflex gain following changes in the stance task. The study concludes with a discussion of the role of stretch reflexes within a hierarchy of controls ranging from muscle stiffness up to centrally initiated responses.

Adaptation, Physiological↗

Effects of pressure stimulation of the body surface on posture and vestibulospinal reflexes.

The effects of pressure stimulation of the body surface on postural activities as well as on the response gain of limb extensors to natural stimulation of labyrinth receptors were investigated in intact, as well as in decerebrate cats. In intact, unanesthetized cats, slight pressure applied symmetrically to the body surface at the chest level decreased the tonic activity of the axial (neck) and limb extensor musculature, as well as the proprioceptive reflexes induced by passive flexion of the limbs. The positive supporting reaction caused by pressure applied to the pad of the foot was also depressed. If the cats were suspended in the air by their nape, slight pressure applied to the upper part of the body greatly reduced the tonic contraction of the forelimb extensors to linear acceleration after downward movement of the animal, a response which can be attributed to stimulation of macular receptors located in the sacculus. Moreover, the prominent myotatic reflexes which occurred in all four limbs as soon as the animal touched the floor were greatly depressed, as shown by the fact that the forelimbs displayed only a slight tonic contraction of the extensor musculature during landing, while the hindlimbs collapsed under the weight of the body. In precollicular decerebrate cats there was a good postural activity in all four limbs. Moreover, the multiunit EMG activity of the medial head of the triceps brachii responded to roll tilt of the animal (at 0.15 Hz, +/- 10 degrees) leading to selective stimulation of labyrinth receptors. These responses, characterized by an increased EMG activity during side-down tilt and a decreased activity during side-up tilt, were related to animal position and not to velocity of animal displacement, and are thus attributable to stimulation of macular, utricular receptors. Slight pressure applied to the chest greatly decreased not only the postural activity of the limbs, but also the amplitude of EMG modulation and then the gain in the first harmonic component of the multiunit EMG responses of the triceps brachii to animal tilt. This reduced gain was due, in particular, to a reduced number of motor units being recruited during labyrinth stimulation, although a reduced modulation of firing rate of the active motor units should not be ruled out. However, no changes in the phase angle of the responses were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Influence of posture on cardiorespiratory reflexes in normal subjects and patients with diabetes mellitus.

This study was designed to assess the effect of patient posture, either sitting or supine, on the results and diagnostic yield of tests of cardiorespiratory reflexes on 25 normal subject controls and 128 patients with diabetes mellitus. The heart rate changes during slow breathing at 6 per minute (delta R6) and during a Valsalva manoeuvre (highest heart rate during manoeuvre divided by lowest heart rate within 30 s after manoeuvre; Valsalva ratio) were measured from the electrocardiographic signal and tachometry. In control subjects, heart rate changes during slow breathing averaged 25.0 when sitting and 21.3 when supine (p < 0.01); Valsalva ratio averaged 1.90 and 1.83 (p > 0.2) respectively. In diabetic patients, mean values for heart rate changes during slow breathing were 6.1 and 5.1, and mean values for Valsalva ratio were 1.23 and 1.28 in sitting and supine postures respectively. According to our normal limits, heart rate changes during slow breathing was below normal in 109 patients tested when sitting and in 113 tested when supine, and Valsalva ratio was abnormal in 103 and 95 respectively. These results indicate that subject posture is an important variable of cardio-respiratory reflex testing, and should be standardized to allow comparisons of individual results.

Adult↗

Indicators of the influence a peripheral vestibular deficit has on vestibulo-spinal reflex responses controlling postural stability.

For a controlled sway stabilization task, the areas underlying EMG responses in ankle and neck muscles, as well as amplitudes of ankle torque responses, were shown to be significantly correlated with the clinically defined extent of a patient's peripheral vestibular deficit. The responses, elicited by ankle dorsiflexion of the support surface on which the subject stood, were statistically examined in order to select those measurements which would best indicate differences between a normal, a patient with a unilateral deficit, or one with a bilateral deficit. For this purpose, a stepwise discriminant analysis was performed on measurements of head and trunk angular accelerations in addition to muscle EMG and ankle torque signals. The primary measurements selected to optimally assign a subject to a population were the periods of ankle torque and neck extensor activity associated with correcting for the imposed body displacement backwards and maintaining upright head position respectively. The resulting division into populations was 100% correct. However, within the population of unilateral deficit patients, the technique failed to correctly identify those with acute from those with compensated deficit. This technique of investigating vestibulo-spinal reflex responses is more specific and sensitive than Romberg tests, because it will quantify and specify the underlying cause of the patient's balance and ambulatory disorder.

Adult↗