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Journal of Neurology, Neurosurgery, and... Jan 2024Biallelic expansion of AAGGG in the replication factor complex subunit 1 () was identified as a major cause of cerebellar ataxia, neuropathy (sensory ganglionopathy, or...
BACKGROUND
Biallelic expansion of AAGGG in the replication factor complex subunit 1 () was identified as a major cause of cerebellar ataxia, neuropathy (sensory ganglionopathy, or SG) and vestibular areflexia syndrome (CANVAS). We wanted to clarify if expansions can present with pure ataxia and if such expansions could be responsible for some cases where an alternative diagnosis had been made.
METHODS
We identified patients with a combination of ataxia and SG and no other cause found, patients where an alternative diagnosis had been made, and patients with pure ataxia. Testing for expansions was done using established methodology.
RESULTS
Among 54 patients with otherwise idiopathic sporadic ataxia without SG, none was found to have expansions. Among 38 patients with cerebellar ataxia and SG in which all other causes were excluded, 71% had expansions. Among 27 patients with cerebellar ataxia and SG diagnosed with coeliac disease or gluten sensitivity, 15% had expansions.
CONCLUSIONS
Isolated cerebellar ataxia without SG makes the diagnosis of CANVAS due to expansions highly improbable, but CANVAS is frequently the cause of the combination of idiopathic cerebellar ataxia with SG. It is important to screen patients diagnosed with other causes of acquired ataxia and SG as a small percentage were found to have expansions.
Topics: Humans; Ataxia; Bilateral Vestibulopathy; Cerebellar Ataxia; Reflex, Abnormal; Syndrome
PubMed: 37414537
DOI: 10.1136/jnnp-2023-331381 -
Anales Del Sistema Sanitario de Navarra 2011
Topics: Accidental Falls; Adult; Arthritis, Rheumatoid; Humans; Hypothyroidism; Male; Muscular Diseases; Reflex, Abnormal
PubMed: 21532650
DOI: 10.4321/s1137-66272011000100010 -
The New England Journal of Medicine Oct 2018
Topics: Humans; Hypothyroidism; Male; Middle Aged; Reflex, Abnormal; Thyrotropin
PubMed: 30281985
DOI: 10.1056/NEJMicm1713796 -
Journal of Neurology, Neurosurgery, and... Jun 1971Seven patients are presented in whom a prominent corneomandibular reflex was observed. These patients all had severe cerebral and/or brain-stem disease with altered...
Seven patients are presented in whom a prominent corneomandibular reflex was observed. These patients all had severe cerebral and/or brain-stem disease with altered states of consciousness. Two additional patients with less prominent and inconsistent corneomandibular reflexes were seen; one had bulbar amyotrophic lateral sclerosis and one had no evidence of brain disease. The corneomandibular reflex, when found to be prominent, reflects an exaggeration of the normal. Therefore one may consider the corneomandibular hyper-reflexia as possibly due to disease of the corticobulbar system.
Topics: Adult; Amyotrophic Lateral Sclerosis; Brain Diseases; Cognition Disorders; Coma; Consciousness; Cornea; Female; Functional Laterality; Humans; Male; Mandible; Middle Aged; Movement Disorders; Reflex; Reflex, Abnormal
PubMed: 5571310
DOI: 10.1136/jnnp.34.3.236 -
Journal of Applied Physiology... May 2010
Topics: Cognition; Cough; Exercise; Feedback, Sensory; Heart Rate; Humans; Hyperventilation; Reflex, Abnormal; Respiratory Mechanics; Sensory Thresholds; Volition
PubMed: 20185634
DOI: 10.1152/japplphysiol.00177.2010 -
Arquivos de Neuro-psiquiatria Sep 2005Data on the prevalence of primitive reflexes (PR) in adulthood, their pathological significance and relationship to age and cognition are controversial.
BACKGROUND
Data on the prevalence of primitive reflexes (PR) in adulthood, their pathological significance and relationship to age and cognition are controversial.
OBJECTIVE
To study the relationship between PR and cognition in 30 patients with probable Alzheimer's disease (AD) and 154 control subjects.
METHOD
Diagnosis of probable AD was based on DSM-IV, NINCDS-ADRDA, and CAMDEX criteria. Primitive reflexes were quantified from zero (absent) to 1 (mild) or 2 (markedly present). The Cognitive Abilities Screening Instrument-Short Form (CASI-S) was used to evaluate registration, temporal orientation, verbal fluency and recall. A drawing test was added.
RESULTS
Most frequent PR among demented and controls were suck (77% and 62%, respectively) and snout (60% and 27%), followed by glabellar (30% and 19%), paratonia (37% and 5%), and palmomental (23% and 5%). None of controls had more than three PR. Frequency of PR tended to increase with age and cognitive deterioration. Grasp and Babinski responses were found only in dementia patients. Primitive reflexes were not correlated with each other, except snout with suck, and snout with glabellar reflex.
CONCLUSION
The finding of grasp and Babinski sign, or the presence of more than three primitive signs, particularly the combination of paratonia, snout, suck, and palmomental reflexes strongly suggests brain dysfunction, especially when these signs are marked and accompanied by deficits in orientation, recall, verbal fluency, and constructional praxis.
Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Case-Control Studies; Cognition Disorders; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Prevalence; Psychiatric Status Rating Scales; Reflex, Abnormal; Severity of Illness Index
PubMed: 16172703
DOI: 10.1590/s0004-282x2005000400004 -
Physiological Reports Oct 2019Obesity is associated with balance and motor control deficits. We have recently shown that Group Ia muscle spindle afferents, the sensory arm of the muscle stretch...
Obesity is associated with balance and motor control deficits. We have recently shown that Group Ia muscle spindle afferents, the sensory arm of the muscle stretch reflex, are less responsive in mice fed a high-fat diet. Here we test the hypothesis that reflex excitability to sensory information from Group Ia muscle spindle afferents is altered in a mouse model of diet-induced obesity. We measured the anesthetized Hoffmann's or H-reflex, the electrical analog of the muscle stretch reflex. Adult mice of both sexes were fed a control diet (CD; 10% kcal from fat) or a high-fat diet (HFD; 60% kcal from fat) for 5, 10, or 15 weeks. We used three quantitative measures of H-reflex excitability: (1) H-reflex latency; (2) the percentage of motor neurons recruited from electrical stimulation of Group Ia muscle spindle afferents (H /M ); and (3) rate-dependent depression (RDD), the decrease in H-reflex amplitude to high frequency stimulation (20 stimuli at 5 Hz). A HFD did not significantly alter H latency (P = 0.16) or H /M ratios (P = 0.06), but RDD was significantly lower in HFD compared to CD groups (P < 0.001). Interestingly, HFD males exhibited decreased RDD compared to controls only after 5 and 10 weeks of feeding, but females showed progressive decreases in RDD that were only significant at 10 and 15 weeks on the HFD. These results suggest that high-fat feeding increases H-reflex excitability. Future studies are needed to determine whether these changes alter muscle stretch reflex strength and/or balance and to determine the underlying mechanism(s).
Topics: Animals; Diet, High-Fat; Electric Stimulation; Female; H-Reflex; Male; Mice; Motor Neurons; Muscle Contraction; Muscle Spindles; Muscle, Skeletal; Obesity; Reflex, Abnormal
PubMed: 31660698
DOI: 10.14814/phy2.14271 -
Journal of Neurology, Neurosurgery, and... Sep 2004Hyperekplexia and the stiff-man syndrome (SMS) are both conditions with exaggerated startle suggesting abnormal brainstem function. Investigation of brainstem reflexes...
BACKGROUND AND OBJECTIVES
Hyperekplexia and the stiff-man syndrome (SMS) are both conditions with exaggerated startle suggesting abnormal brainstem function. Investigation of brainstem reflexes may provide insight into disturbed reflex excitation and inhibition underlying these movement disorders.
PATIENTS AND METHODS
Using four-channel EMG, we examined four trigeminal brainstem reflexes (monosynaptic masseter, masseter inhibitory, glabella, and orbicularis oculi blink reflexes) and their spread into pericranial muscles in five patients with familial hyperekplexia (FH), two with acquired hyperekplexia (AH), 10 with SMS, and 15 healthy control subjects.
RESULTS
Both FH/AH and SMS patients had abnormal propagation of brainstem reflexes into pericranial muscles. All patients with hyperekplexia showed an abnormal short-latency (15-20 ms) reflex in the trapezius muscle with a characteristic clinical appearance ("head retraction jerk") evoked by tactile or electrical stimulation of the trigeminal nerve, but normal monosynaptic masseter reflexes. Inhibitory brainstem reflexes were attenuated in some FH/AH patients. Four of 10 patients with SMS had similar short-latency reflexes in the neck muscles and frequently showed widespread enhancement of other excitatory reflexes, reflex spasms, and attenuation of inhibitory brainstem reflexes.
CONCLUSION
Reflex excitation is exaggerated and inhibition is attenuated in both stiff-man syndrome and familial or acquired hyperekplexia, indicating a physiological relationship. Reflex transmission in the brainstem appears biased towards excitation which may imply dysfunction of inhibitory glycinergic or GABAergic interneurons, or both.
Topics: Adolescent; Adult; Aged; Brain Stem; Case-Control Studies; Child; Child, Preschool; Electromyography; Female; Humans; Infant; Male; Middle Aged; Reaction Time; Reflex, Abnormal; Reflex, Startle; Stiff-Person Syndrome; Trigeminal Nerve
PubMed: 15314112
DOI: 10.1136/jnnp.2003.018135 -
American Journal of Physiology. Heart... Apr 2013Static muscle contraction activates the exercise pressor reflex, which in turn increases sympathetic nerve activity (SNA) and blood pressure (BP). Bradykinin (BK) is...
Static muscle contraction activates the exercise pressor reflex, which in turn increases sympathetic nerve activity (SNA) and blood pressure (BP). Bradykinin (BK) is considered as a muscle metabolite responsible for modulation of the sympathetic and cardiovascular responses to muscle contraction. Prior studies have suggested that kinin B2 receptor mediates the effects of BK on the reflex SNA and BP responses during stimulation of skeletal muscle afferents. In patients with peripheral artery disease and a rat model with femoral artery ligation, amplified SNA and BP responses to static exercise were observed. This dysfunction of the exercise pressor reflex has previously been shown to be mediated, in part, by muscle mechanoreflex overactivity. Thus, in this report, we determined whether kinin B2 receptor contributes to the augmented mechanoreflex activity in rats with 24 h of femoral artery occlusion. First, Western blot analysis was used to examine protein expression of B2 receptors in dorsal root ganglion tissues of control limbs and ligated limbs. Our data show that B2 receptor displays significant overexpression in ligated limbs as compared with control limbs (optical density: 0.94 ± 0.02 in control and 1.87 ± 0.08 after ligation, P < 0.05 vs. control; n = 6 in each group). Second, mechanoreflex was evoked by muscle stretch and the reflex renal SNA (RSNA) and mean arterial pressure (MAP) responses to muscle stretch were examined after HOE-140, a B2 receptors blocker, was injected into the arterial blood supply of the hindlimb muscles. The results demonstrate that the stretch-evoked reflex responses were attenuated by administration of HOE-140 in control rats and ligated rats; however, the attenuating effects of HOE-140 were significantly greater in ligated rats, i.e., after 5 μg/kg of HOE-140 RSNA and MAP responses evoked by 0.5 kg of muscle tension were attenuated by 43% and 25% in control vs. 54% and 34% in ligation (P < 0.05 vs. control group; n = 11 in each group). In contrast, there was no significant difference in B1 receptor expression in both experimental groups, and arterial injection of R-715, a B1 receptors blocker, had no significant effects on RSNA and MAP responses evoked by muscle stretch. Accordingly, results obtained from this study support our hypothesis that heightened kinin B2 receptor expression in the sensory nerves contributes to the exaggerated muscle mechanoreflex in rats with femoral artery occlusion.
Topics: Animals; Arterial Pressure; Baroreflex; Bradykinin; Bradykinin B1 Receptor Antagonists; Bradykinin B2 Receptor Antagonists; Disease Models, Animal; Femoral Artery; Ganglia, Spinal; Ligation; Male; Muscle Contraction; Muscle Spindles; Muscle, Skeletal; Peripheral Arterial Disease; Rats; Rats, Sprague-Dawley; Receptor, Bradykinin B1; Receptor, Bradykinin B2; Reflex, Abnormal; Sympathetic Nervous System
PubMed: 23417862
DOI: 10.1152/ajpheart.00926.2012 -
Neurologia Oct 2020
Topics: Cerebellar Ataxia; Foot Deformities, Congenital; Hearing Loss, Sensorineural; Humans; Optic Atrophy; Reflex, Abnormal
PubMed: 31780320
DOI: 10.1016/j.nrl.2019.09.002