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PubMed1991

[Treatment of focal dystonia with botulinum toxin].

We have studied the effect of botulinum toxin in patients with focal dystonia, not responding sufficiently to medical therapy. Injection of 5-100 units to the muscles, selected by EMG and clinical examination, invariably resulted in reduction of muscle tonus, although to a different degree depending on the dosage. The outcome after the first trial was best when dealing with small muscles in patients with blephalospasm or Meige's syndrome. In contrast, several attempts were required for the treatment of a large muscle as in torticollis, or multiple muscles as in writers' cramps. The effect lasted 1-3 months. With precise selection of the affected muscles and careful regulation of necessary dosages, this type of therapy may contribute to the treatment of focal dystonia.

Adult↗
PubMed2000

Ultrastructural observations of fibroblast-like cells forming gap junctions in the W/W(nu) mouse small intestine.

The ultrastructure of the wild-type (+/+) mice small intestine was compared with c-kit mutant (W/W(nu)) mice which only have few interstitial cells of Cajal (ICC) associated with Auerbach's plexus, in order to elucidate whether the specialized membrane contacts are general features of so-called fibroblast-like cells that are widely distributed in the tunica muscularis of the alimentary tract. Fibroblast-like cells in the Auerbach region were found in approximately equal number in W/W(nu) mice as in +/+ mice, while ICC associated with Auerbach's plexus (ICC-AP) could not be demonstrated in W/W(nu) mice in the present investigation. Fibroblast-like cells were characterized by cytoplasm of moderate to high electron density, well developed rough endoplasmic reticulum and nuclei with thick peripheral accumulations of heterochromatin. There were no basal lamina and caveolae along the cell membrane. It was observed that single fibroblast-like cells formed probable small gap junctions with muscle cells of both circular and longitudinal layers. Fibroblast-like cells with the same features were also observed in the region of the deep muscular plexus in both +/+ and W/W(nu) mice. The present observation, together with our previous studies on rats and guinea-pigs, suggest the common presence of gap junctions or gap junction-like structures on fibroblast-like cells in the gastrointestinal musculature and their involvement in the regulatory system of gastrointestinal motility by passing electrical or molecular signals to influence the state of muscle tonus.

Animals↗
PubMed1983

Encephalopathic effect of phenol in rats.

The coma-inducing effect of phenol was studied in normal 300 +/- 50 gm Sprague-Dawley rats. Dose-response curves were developed which showed that one-half the animals became deeply comatose with 540 mumol of intraperitoneal phenol and 100% with 600 mumol. Five stages of encephalopathy were readily distinguished. In stage I, spontaneous activity was noticeably decreased, posture was upright, back-leg control normal, muscle tonus slightly increased, and response to stimuli normal. In Stage V, activity was gone, the rats were deeply unconscious, righting reflex and back-leg control were gone, muscles were completely relaxed, and there was no response to stimuli. With a coma-inducing dose of phenol, spontaneous activity decreased. After 1 min a body tremor developed interspersed with unpredictable jumping, and all four limbs began to shake. Leg control and then the righting reflex were lost by 2 min. Within 5 min rats were deeply unconscious and muscles completely relaxed while shaking of limbs continued until recovery 20 to 60 min later or death. With 480 mumol or less, none of the rats became comatose, but the shaking of limbs was present. The coma-inducing dose of phenol was reduced by 10% to 20% with simultaneous injection of subcoma doses of NH4+ or OA and by 20% to 30% with simultaneous DMDS leads to 2 methanethiol. Conversely, a subcoma dose of phenol reduced the coma-inducing doses of NH4+, OA, and DMDS by approximately 20% to 25%. Thus phenol, which accumulates in human hepatic failure, induces coma by itself in rats and acts synergistically with other hepatic failure toxins.

Animals↗
PubMed2005

Evaluation of varicocele frequency of patients with spinal cord injury by color Doppler ultrasonography: a new etiological factor for varicocele?

PURPOSE: To evaluate the varicocele frequency of patients with spinal cord injury by color Doppler ultrasonography. MATERIALS AND METHODS: Sixty patients {48 patients with upper motor neuron injury (U-MNI) and 12 patients with lower-MNI} with traumatic spinal cord injury and age matched 48 healthy volunteers were enrolled in this prospective study. Testis volumes and varicocele grades were determined. Presence of varicocele was also classified according to clinical significance. RESULTS: Testis volumes of U-MNI sub-group (14.81 +/- 4.74 ml) were significantly smaller than the control group (18.20 +/- 4.52 ml, p = 0.000) and L-MNI sub-group (17.88 +/- 3.23 ml, p = 0.008). No left-sided clinical varicocele was found in L-MNI sub-group (0/12, 0%), whereas there were 14 patients in control group (14/48, 29%) and 7 patients in U-MNI sub-group (7/47, 15%), and the difference was statistically significant (p = 0.000, 0.007, respectively). CONCLUSION: Clinical varicocele frequency of U-MNI patients, who have spastic paralysis of abdominal and lower extremity muscles, is similar to the control group. This finding inspires that increased intra-abdominal pressure via normal to increased abdominal muscle tonus may have a role in the varicocele etiology, beside the classical factors. Absence of clinical varicocele in L-MNI patients, who have flaccid paralysis of the same muscle groups, supports this observation.

Adult↗
PubMed1983

[Vesicourethral physiology during continence and urination in cats. In vivo and in vitro studies].

The mechanisms implicated in the opening of the bladder neck during voiding are still controversial. We present a study of the reflexes of bladder, urethra and periurethral striated muscles in the cat. The study in vivo shows that a passive muscle tonus of the urethra is able to maintain the continence. During voiding, opening of the bladder outlet is done actively: contraction of the longitudinal and relaxation of the circular muscle layers of the urethra associated with detrusor contraction. There is a local reflex between the urethra, bladder and periurethral striated muscles that completes emptying of the bladder with an interrupted stream. The study in vitro confirms that the 2 muscle layers of the urethra have different innervation: the parasympathomimetic agents act on the longitudinal layer and very weakly on the circular. Both layers react to adrenergic stimulation.

Animals↗
PubMed1994

[Motor organization in children with encopresis].

The paper reviews the degree of fecal retention in regard to organization of certain functions of central nervous system (motoric, vegetative and psychic), as well as to certain qualities of motoric organization by means of correlation analysis. Gathered results point to connection between poor tonic organization, especially of the axial muscle tonus and neuromuscular binds and the degree of fecal retention; correlations are positive, linear, so that poor motoric organization can be considered basic for the disorder of the pelvic floor muscles function and consequent encopresis.

Adolescent↗
PubMed2001

Electrophysiological, histological, and behavioral studies in a cat with acute compression of the spinal cord.

We made an animal model of cervical spinal cord injury in a cat and performed electrophysiological, histological, and bechavioral studies. The cervical spinal cord injury model was made by inserting a screw through the fourth cervical vertebral body of the cat. After the injury, muscle tonus of the limbs and trunk diminished. The cat was able to walk and to perform target reaching after the injury, although the trunk was unstable and the movement of the forelimb was ataxic. Atrophy of the back muscle remained. The cat was unable to stand bipedally. These behavioral disturbances suggested dysfunction of the ventral funiculus. After behavioral analysis for 3 months, an electrophysiological study was performed. Action potentials of the ventral funiculus evoked by stimulation of the lateral vestibular nucleus or the medial longitudinal fasciculus were recorded at several levels of the cervical cord. They were diminished at levels caudal to the compression site. After the recording, the cervical cord was studied histologically. There was demyelination and gliosis in the ventral funiculus and in part of the ventrolateral funiculus at or near the injured site. Electrophysiological and histological findings were in good agreement with the behavioral ones. Behavioral studies seem useful for evaluating the function of the spinal cord, especially for assessing the injured system in the spinal cord.

Animals↗
PubMed2005

Postural sway during single and repeated cold exposures.

INTRODUCTION: Tissue cooling changes sensory and neuromuscular functions that are also involved in postural control. The purpose of the study was to determine how acute and repeated exposures to cold affect whole body postural control. METHODS: Postural sway was measured from 10 subjects during standing with eyes open (EO) and closed (EC) using an inclinometer-based method. Sway was assessed at at 10 degrees C on 10 consecutive days and at 25 degrees C on days 1, 5, and 10. Sway path length, area, velocity, side-to-side and forward-backward movement were assessed. At the same time, rectal and skin temperatures, muscle tonus/ shivering, thermal sensations, and comfort were recorded. RESULTS: Acute exposure to 10 degrees C caused thermal discomfort, significantly lowered (26.1-26.5 degrees C) mean skin temperatures, slightly lowered rectal temperature (36.7 degrees C) and increased (140-260%) muscle tone, increased sway path length (67-87%, p < 0.05), velocity (63-71%, p < 0.05), total sway area (42-67%, p < 0.05), and forward-backward movement (35-57%, p < 0.05) compared with 25 degrees C. Side-to-side movements were not altered in the cold. Postural sway increased with EC, and further when exposed to cold, but the effect of cold was smaller compared with EO. Repeated exposures over the 10-d period decreased sway 10-40% both at 25 degrees C and at 10 degrees C (p < 0.05-0.01), suggesting motor learning. The difference in sway between 25 degrees C and 10 micro C remained the same throughout the 10-d period, suggesting that the observed cold habituation responses do not affect sway. CONCLUSIONS: The results demonstrate that postural control is impaired in cold, which may affect physical performance in cold environmental conditions.

Adult↗
PubMed1980

[Neck muscular tension due to repetitive work].

In our laboratory study 19 students effected 4 repetitive tasks of 70 min each. All four conditions had a motor task at the base and in addition two had to deal with discrimination. In the 2 tasks with discrimination, the electromyography of the neck muscles was distinctly higher than in the 2 other conditions. The tasks with discrimination were accompanied by a higher subjective tension, a lower heart rate variability and a slightly increased urinary excretion. The main cause for an augmentation in the muscle tonus might be the immobilisation of the neck.

Electromyography↗
PubMed1989

Seemingly paradoxical jumping in cataleptic haloperidol-treated rats is triggered by postural instability.

Paradoxically, animals exhibiting haloperidol-induced cataleptic immobility can be induced to leap vigorously, by pushing them forward from behind. It is shown here that such jumping can also be produced by placing them on a board and tilting it tail-end upward until about 50 degrees above horizontal. In both situations, jumps only occurred when the animal's hindlegs began to slip forward, as they lost their postural stability. As alternatives to jumping from the slope, rats turned to face upwards (negative geotaxis), or adopted a spread-eagled posture during head-first downward sliding, with the body and head flattened against the substrate. All 3 responses to the sloping board were present in some undrugged rats. Such rats, and those given low doses of haloperidol (0.5, 1.0 mg/kg), were more likely to turn upwards than to jump or slide. At high doses (7.5, 10.0 mg/kg), they were more likely to slide downward than to turn or jump. Jumping was most likely to occur at an intermediate dose (5 mg/kg), approximately 60 min after injection. We suggest that in the absence of haloperidol, and at low doses, locomotion is dominant over reflexes defending static equilibrium, and hence rats are more likely to turn upwards (which involves stepping). In contrast, at higher doses, locomotion is more fully suppressed, reducing the likelihood of turning. At very high doses of haloperidol and later in the action of the drug, muscle tonus appears to be weakened, reducing the likelihood of jumping. This possibility was supported by the finding that combined injection of the optimal dose of haloperidol and 2 mg/kg diazepam reduced the ability to cling vertically (suggesting weakness of muscle tone). In such rats, jumping from the sloping board was decreased, and active downward sliding was increased. Thus, different factors influence the occurrence of jumping at different doses of haloperidol. However, these are all active defensive responses to postural instability, and hence are similar to the other reflexes used by haloperidol-treated rats to defend against displacement from static stable equilibrium, such as standing immobile, bracing, clinging, and righting. Jumping in response to loss of stability on the sloping board also occasionally occurred in undrugged rats. Unlike jumps by haloperidol-treated rats, those by undrugged animals only occurred when they could be directed to a safe landing place. Thus, if the board faced the edge of the table, so that the jump would carry the animal into space over the edge, undrugged rats either did not jump or jumped off the side of the board onto the table.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMedDate not supplied

[Neuroleptic malignant syndrome in a patient with polyneuropathy: mechanism of muscle rigidity and elevated serum creatine kinase levels].

A 49-year-old man was admitted with the chief complaints of muscle weakness and gait disturbance. His neurological examination was compatible with peripheral neuropathy, and laboratory tests revealed IgA monoclonal gammopathy, increased protein content in the cerebrospinal fluid (CSF) without pleocytosis, and slow motor and sensory nerve conduction velocity. He was diagnosed as having chronic inflammatory demyelinating polyneuropathy with IgA monoclonal gammopathy of undetermined significance. The patient was treated with steroid, and plasmapheresis. He became so restless that antidepressant and haloperidol were administered. Then, he became unresponsive, and developed high fever, sweating, tachycardia, and tremor. Examination of CSF showed increased 3-methoxy-4-hydroxy-phenylglycol and decreased homovanillic acid. He was diagnosed as having neuroleptic malignant syndrome (NMS). However, his muscle tonus was still flaccid in his lower extremities that had been suffered from chronic polyneuropathy. Interestingly, his serum creatine kinase (CK) content was only slightly elevated. We suppose that the pathophysiological location of NMS might be primarily central, and that muscle rigidity and elevation of serum CK might not occur, if the peripheral nerves were completely impaired.

Creatine Kinase↗
PubMed2003

5-HT7 receptor-mediated relaxation of the oviduct in nonpregnant proestrus pigs.

The effects of 5-hydroxytryptamine (5-HT) on the muscle tonus of the ampulla and isthmus of the oviduct isolated from nonpregnant proestrus pigs were investigated, and the 5-HT receptor subtype and mechanisms of the responses were analyzed. 5-HT (1 nM-10 microM) caused a relaxation of longitudinal and circular muscles of the isthmus in a concentration-dependent manner. Tetrodotoxin did not change the relaxation, indicating a direct action of 5-HT on smooth muscle cells. The EC(50) value in the longitudinal muscle was significantly lower than that in the circular muscle but the maximum relaxations were similar. 5-HT also caused a relaxation of both muscle layers in the ampulla but the maximum relaxation of both muscles was smaller than that of the isthmus. 5-Carboxamidotryptamine (5-CT), 5-methoxytryptamine (5-MeOT) and (+/-)-8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) mimicked the relaxation of the isthmic longitudinal muscle by 5-HT, and the ranking order was 5-CT>5-HT>5-MeOT>8-OH-DPAT. On the other hand, oxymethazoline, 2-methyl-5-hydroxytryptamine (2-methyl-5-HT), alpha-methyl-5-hydroxytryptamine (alpha-methyl-5-HT), [endo-N-8-methyl-8-azabicyclo-(3,2,1) oct-3-yl]-2,3-dihydro-3-ethyl-2-oxo-1H-benzimidazol-1-carboxamide (BIMU-1), ergotamine and dihydroergotamine were less effective. The relaxation by 5-HT was not decreased by ketanserin, 2-methoxy-4-amino-5-chlorobenzoic acid 2-(diethylamino)ethyl ester (tropisetron) or [1[2-(methylsulphonyl) amino ethyl]-4-piperidinyl]methyl-1-methyl-1H-indole-3-carboxylate (GR113808) but was antagonized by the following compounds in a competitive manner (with pK(b) values in parentheses): 2a-[4-(4-phenyl-1,2,3,6-tetrahydropyridyl)butyl]-2a,3,4,5-tetrahydro-benzo[cd]indol-2(1H)-one (DR4004, 9.31), methiothepin (8.91), methysergide (7.95), metergoline (7.98), mianserin (7.69), mesulergine (8.4), spiperone (6.86) and clozapine (7.4). The correlation of these pK(b) values with pK(i) values of cloned 5-HT(7) receptor or pA(2) values of porcine uterus was high and significant. 4-(3-Butoxy-4-methoxybenzyl)-imidazolidin-2-one (Ro20-1724) significantly enhanced the relaxation by 5-HT but zaprinast, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and L-nitroarginine methylester (L-NAME) did not change the responses to 5-HT. 5-HT increased cyclic AMP in the isthmic oviduct. Ampulla and isthmus contained a single class of [3H]5-CT binding sites with a similar K(d) value (0.4 nM), but the density of the receptors in the isthmus was 2.4 times higher than that in the ampulla. A significant correlation was found between the pK(i) values in the oviduct and those of the cloned 5-HT(7) receptors. Isoprenaline, sodium nitroprusside, vasoactive intestinal peptide and pituitary adenylate cyclase activating peptide were less effective in causing the relaxation of the oviduct. In conclusion, the 5-HT receptor, functionally correlated to the 5-HT(7) type, mediates the relaxation of the porcine oviduct by 5-HT through an increase in intracellular cyclic AMP. The degrees of 5-HT-induced relaxation in the isthmus and ampulla of the oviduct were different due to the heterogeneous distribution of 5-HT(7) receptors. The strongest relaxation through 5-HT(7) receptor activation suggests that 5-HT plays an important physiological role in the regulation of porcine oviduct contractility.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMedDate not supplied

Postural control responses sitting on unstable board during visual stimulation.

Concerning with the relation of vection induced by the optokinetic stimulation and the body movement, especially we attended to the neck joint movement, which counteracted to the shoulder movement. Then, we analyzed the mechanisms of the sitting postural control by using the seesaw board. By the optokinetic stimulation through the head mounted display (H.M.D.), the vection was leaded, and it affected to the sway of the body on the seesaw board. In this experiment, we found that the movement of upper part of body except for the head was the same direction to the seesaw board but the head moved out of phase to the seesaw board. This phenomenon will be suggested that the unstable condition of sway is balanced by the counter swing of head and the neck muscle tonus is controlled by acting of the vestibulo-collic reflex.

Adult↗
PubMed1989

[Respiratory pattern and activity of the abdominal muscles after upper abdominal surgery].

Because only few data is as yet available concerning abdominal muscle activity following upper abdominal surgery, the present study aimed to investigate the pattern of abdominal muscle activity before and after upper abdominal surgery and to relate any changes to differences in abdominal respiratory movements. Eight ASA I patients (5 women, 3 men), mean age 44 +/- 12 yr, undergoing elective cholecystectomy (midline incision) were investigated. The following parameters were measured, with the patients supine and at rest, on the eve of surgery, and 2, 4, 24 and 72 h afterwards: tidal volume (VT), breathing rate (f), inspiratory time (TI), total cycle time (TT), changes in abdominal (Dab) and thoracic (Drc) circumferences, surface electromyograms of the rectus abdominis and obliquus externus abdominis muscles. The ratio (Dab/Dab + Drc) was used as an index of relative abdominal movement. Anaesthetic management was similar for all patients (thiopentone, fentanyl, vecuronium, halothane and N2O). A significant reduction in VT was found between 2 and 24 h postoperatively, with a significant increase in f between 4 and 24 h after surgery. Both these parameters returned to normal values at the 72nd h. Relative abdominal movement was reduced in the immediate postoperative period (2 and 4 h), slowly improving, but remaining lower than normal at 72 h. Muscle tonus was increased at 2 h and returned to normal at the 4th h. This transient increase suggested a residual effect of fentanyl.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗
PubMed2002

Treatment of condylar hypoplasia with distraction osteogenesis: a case report.

This report describes the surgical-orthodontic treatment procedures of a patient with condylar hypoplasia. Condylar hypoplasia is a major factor in any facial abnormality in a growing child. This case report describes a patient with a facial anomaly with an acquired unilateral condylar hypoplasia. His asymmetry was corrected by using functional therapy for the correction of muscle tonus and distraction osteogenesis for lengthening the mandibular ramal height. Fixed orthodontic appliances were used for conventional orthodontic therapy and final occlusal adjustment.

Bite Force↗
PubMed1993

[Neurologic semiology in a population of hearing impaired children].

A random sample of 42 sensorineural hearing impaired children (severe and bilateral) was studied, from special classes in Campinas, with chronological ages varying between 4 and 7 years old. The children of this sample were compared with two control groups of 42 children of the same chronological age, from regular classes of private and public schools. All of them were submitted to the traditional neurological examination. Hearing impaired children showed differences as to head circumference and muscle tonus. In the other examined items we found motor hyperactivity, cerebellar and ocular syndromes although there were no significant differences between the groups.

Age Factors↗
PubMed1992

Inhibitory actions of dopamine on Limulus visceral muscle involve a cyclic AMP-dependent mechanism.

1. The catecholamines dopamine, epinephrine and norepinephrine were detected in alumina extracts of Limulus midgut tissue using high performance liquid chromatography with electrochemical detection. Moderate levels of norepinephrine (28.2 +/- 2.1 ng/g) and dopamine (24.0 +/- 5.2 ng/g) were detected in the midgut, while epinephrine levels (7.4 +/- 0.9 ng/g) were less. Catecholamines were present in all regions along the longitudinal axis of the midgut, and norepinephrine and dopamine levels were highest in posterior regions. 2. Catecholamines decreased muscle tonus and inhibited spontaneous contractions of the Limulus midgut. Dopamine typically decreased spontaneous midgut activity at doses of 10(-8) M or greater, and produced inhibitory actions on all regions of the Limulus midgut. In some preparations epinephrine and norepinephrine elicited a secondary rhythmicity. The actions of dopamine opposed the excitatory effects produced by either proctolin or octopamine. 3. Catecholamines significantly elevated levels of cyclic AMP in Limulus midgut muscle rings. Dopamine (10(-5) M) increased cyclic AMP with a time course consistent with its physiological effects. Forskolin and several methyl xanthines increased Limulus midgut cyclic AMP levels and mimicked the inhibitory effects of dopamine on the isolated midgut preparation. Cyclic nucleotide analogues also produced dopamine-like effects on the isolated midgut preparation. Inhibition of cyclic nucleotide phosphodiesterase prior to addition of dopamine enhanced the effect of this amine to decrease baseline muscle tension. 4. The inhibitory effects of 10(-5) M dopamine on the midgut persisted in solutions of zero sodium and in the presence of tetrodotoxin. Zero calcium solutions gradually reduced spontaneous midgut activity and the effects of dopamine. Calcium channel blockers did not prohibit dopamine-induced relaxation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗