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The aims of this study were: (i) to determine kinematic, kinetic, and electromyographic characteristics of Junzuki karate punch in professional karate athletes; (ii) to identify biomechanical parameters that correlate with punch force and lead to a higher punching performance; (iii) to verify the presence of muscle co-activation in the upper limb, trunk, and lower limb muscles. Data were collected from nine experienced karatekas from the Accademia Italiana Karate e Arti Marziali during the execution of the specific punch. Mean punch forces (181.2 N) delivered to the target, the range of motion of both right and left knees (1.13 and 0.82 rad) and right elbow (1.49 rad) joints, and the angles at impact (knee: 0.81 and 0.91 rad; elbow: 1.19 rad) in the sagittal plane were computed. Furthermore, the trunk rotational angular acceleration (63.1 rad s-2), force related to the lower limbs (550.2 and 425.1 N), and co-activation index for the upper limb (36.1% and 34.7%), trunk (24.5% and 16%), and lower limbs (16.0% and 16.1%) muscles were evaluated bilaterally. Significant positive correlations were found between the punch force and both right and left knee flexion at the instant of impact and right and left leg force. Significant negative correlation was found between the punch force and maximum trunk angular acceleration. Significant differences (p = .03) in the co-activation index among the upper limb, trunk, and lower limbs muscles highlighted a rostro-caudal gradient on both body sides. This research could be of use to performers and coaches when considering training preparations. [ABSTRACT FROM AUTHOR]

Objective To search for differences in prevalence of a CACNA1E variant between migraine without aura, various phenotypes of migraine with aura, and healthy controls. Background Familial hemiplegic migraine type 1 (FHM1) is associated with mutations in the CACNA1A gene coding for the alpha 1A (Cav2.1) pore-forming subunit of P/Q voltage-dependent Ca2+ channels. These mutations are not found in the common forms of migraine with or without aura. The alpha 1E subunit (Cav2.3) is the counterpart of Cav2.1 in R-type Ca2+ channels, has different functional properties, and is encoded by the CACNA1E gene. Methods First, we performed a total exon sequencing of the CACNA1E gene in three probands selected because they had no abnormalities in the three FHM genes. In a patient suffering from basilar-type migraine, we identified a single nucleotide polymorphism (SNP) in exon 20 of the CACNA1E gene (Asp859Glu - rs35737760; Minor Allele Frequency 0.2241) hitherto not studied in migraine. In a second step, we determined its occurrence in four groups by direct sequencing on blood genomic DNA: migraine patients without aura ( N = 24), with typical aura ( N = 55), complex neurological auras ( N = 19; hemiplegic aura: N = 15; brain stem aura: N = 4), and healthy controls ( N = 102). Results The Asp859Glu - rs35737760 SNP of the CACNA1E gene was present in 12.7% of control subjects and in 20.4% of the total migraine group. In the migraine group it was significantly over-represented in patients with complex neurological auras (42.1%), OR 4.98 (95% CI: 1.69-14.67, uncorrected P = .005, Bonferroni P = .030, 2-tailed Fisher's exact test). There was no significant difference between migraine with typical aura (10.9%) and controls. Conclusions We identified a polymorphism in exon 20 of the CACNA1E gene (Asp859Glu - rs35737760) that is more prevalent in hemiplegic and brain stem aura migraine. This missense variant causes a change from aspartate to glutamate at position 859 of the Cav2.3 protein and might modulate the function of R-type Ca2+ channels. It could thus be relevant for migraine with complex neurological aura, although this remains to be proven. [ABSTRACT FROM AUTHOR]

Objective To study the influence of the migraine aura on the trigeminal nociception, we investigated the habituation of the nociceptive blink reflex (nBR) R2 responses in aura with migraine headache (AwMH) and comparatively in migraine without aura (MWoA) and healthy subjects (HS). Background A clear deficit of habituation in trigeminal nociceptive responses has been documented in MWoA; however, similar data in MWA are lacking. Methods Seventeen AwMH, 29 MWoA, and 30 HS were enrolled and a nonrandomized clinical neurophysiological study examining nBR habituation by clinical diagnosis was devised. We delivered a series of 26 electrical stimuli, at different stimulation frequencies (SF) (0.05, 0.1, 0.2, 0.3, 0.5, and 1 Hz), subsequently subdivided in five blocks of five responses for each SF. The mean area values of the second to the fifth block expressed as the percentage of the mean area value of the first block were taken as an index of habituation for each SF. Results A significant lower mean percentage decrease of the R2 area across all blocks was found at 1, 0.5, 0.3, and 0.2 Hz SF in MWoA and at 0.3 and 0.2 Hz SF in AwMH, when compared to HS. In the most representative fifth block of responses, we found in MWoA vs HS at 1 Hz, 57.0 ± 27.8 vs 30.6 ± 12.0; at 0.5 Hz, 54.8 ± 26.1 vs 32.51 ± 17.7; at 0.3 Hz, 44.7 ± 21.6 vs 27.6 ± 13.2; at 0.2 Hz, 61.3 ± 29.5 vs 32.6 ± 18.0, and in AwMH vs HS at 0.3 Hz, 52.7 ± 24.7 vs 27.6 ± 13.2; at 0.2 Hz, 69.3 ± 38.6 vs 32.6 ± 18.0 as mean ± SD of the R2 area percentage of the first block, respectively. Interestingly, AwMH subjects did not show differences in mean percentage decrease of the R2 area at 1 and 0.5 Hz SF when compared to HS. No differences between groups were found at 0.1 and 0.05 Hz SF. Conclusions We demonstrated in AwMH a deficit of habituation of the nBR R2 responses after repeated stimulations, although less pronounced than that observed in MWoA of comparable clinical severity. We hypothesize that AwMH and MWoA share some pathogenetic aspects, and also that migraine aura physiopathology may play a modulating role on the excitability of the nociceptive trigeminal pathways. [ABSTRACT FROM AUTHOR]

Monoamines have an important role in neural plasticity, a key factor in cortical pain processing that promotes changes in neuronal network connectivity. Monoamine oxidase type A ( MAOA) is an enzyme that, due to its modulating role in monoaminergic activity, could play a role in cortical pain processing. The X-linked MAOA gene is characterized by an allelic variant of length, the MAOA upstream Variable Number Tandem Repeat ( MAOA-u VNTR) region polymorphism. Two allelic variants of this gene are known, the high-activity MAOA ( HAM) and low-activity MAOA ( LAM). We investigated the role of MAOA-u VNTR in cortical pain processing in a group of healthy individuals measured by the trigeminal electric pain-related evoked potential (t PREP) elicited by repeated painful stimulation. A group of healthy volunteers was genotyped to detect MAOA-u VNTR polymorphism. Electrical t PREPs were recorded by stimulating the right supraorbital nerve with a concentric electrode. The N2 and P2 component amplitude and latency as well as the N2- P2 inter-peak amplitude were measured. The recording was divided into three blocks, each containing 10 consecutive stimuli and the N2- P2 amplitude was compared between blocks. Of the 67 volunteers, 37 were HAM and 30 were LAM. HAM subjects differed from LAM subjects in terms of amplitude of the grand-averaged and first-block N2- P2 responses ( HAM> LAM). The N2- P2 amplitude decreased between the first and third block in HAM subjects but not LAM subjects. The MAOA-u VNTR polymorphism seemed to influence the brain response in a repeated t PREP paradigm and suggested a role of the MAOA as a modulator of neural plasticity related to cortical pain processing. [ABSTRACT FROM AUTHOR]

Objectives.- We investigated (1) a possible relationship between the functional activity of the endocannabinoid system and the facilitation of pain processing in migraineurs with medication-overuse headache, and (2) the effect of withdrawal treatment on both. Background.- The endocannabinoid system antinociception effect includes prevention of nociceptive pathways sensitization. The sensitization of the pain pathways has been demonstrated to be pivotal in the development and maintenance of chronic form of migraine, including medication-overuse headache. Methods.- We used the temporal summation threshold of the nociceptive withdrawal reflex to explore the spinal cord pain processing, and the platelet activity of the enzyme fatty acid amide hydrolase to detect the functional state of the endocannabinoid system in 27 medication-overuse headache subjects before and 10 and 60 days after a standard withdrawal treatment and compared results with those of 14 controls. Results.- A significantly reduced temporal summation threshold and increased related pain sensation was found in subjects before withdrawal treatment when compared with controls. A significant fatty acid amide hydrolase activity reduction coupled with a significant improvement (reduction) in facilitation of spinal cord pain processing (increase in temporal summation threshold and reduction in related pain sensation) was found in medication-overuse headache subjects at both 10 and 60 days after withdrawal treatment when compared with medication-overuse headache subjects before withdrawal treatment. Conclusions.- We demonstrated a marked facilitation in spinal cord pain processing in medication-overuse headache before withdrawal treatment when compared with controls. Furthermore, the acute reduction of the fatty acid amide hydrolase activity coupled with a reduction of the facilitation in pain processing immediately (10 days) after withdrawal treatment and its persistence 60 days after withdrawal treatment could represent the consequence of a mechanism devoted to acutely reduce the degradation of endocannabinoids and aimed to increase the activity of the endocannabinoid system that results in an antinociceptive effect. [ABSTRACT FROM AUTHOR]

Objective.- To study the prevalence of cephalalgia in male divers. Background.- Scuba divers work in stressing environments and have a high cerebrovascular risk, both conditions which are supposed to contribute to the genesis of cephalalgia. However, no study assessed expressly the prevalence of cephalalgia in divers, to date. Methods.- We enrolled 201 professional male scuba divers (41.0 ± 7.2 years) and controls (41.1 ± 7.2 years), and the risk ratio and its corresponding 95% confidence of suffering from cephalalgia was calculated. Results.- We found that 16% of divers and 22% of matched controls were affected by cephalalgia ( P > .05), accounting for a risk ratio of 0.71 (95% CI 0.47-1.07). Divers reported fewer attacks per month (1.8 ± 0.7, n = 32) with regard to controls (2.5 ± 1.8, n = 45) ( P = .02), but no differences concerning age at onset and severity were detected ( P > .05). Divers suffered from migraine, migraine with aura and tension headache as much as controls. Conclusion.- Scuba diving, an intense physical activity characterized by cerebral micro-vascular distress, is not associated with cephalalgia, as a whole, or migraine, tension headache or migraine with aura, more commonly than in a matched, non-diving, population. A longitudinal study may disclose if diving may act as a protective factor in the occurrence of crises of cephalalgia. ( Headache 2012;52:385-392) [ABSTRACT FROM AUTHOR]

Abstract: Nitric-oxide donor glyceryl-trinitrate (GTN) modulates cerebral and spinal regions that are involved in migraine and pain processing. We hypothesized that in migraineurs, the susceptibility to develop a migraine attack after GTN administration should parallel with an high sensitivity to GTN-induced change in the pain processing at spinal level. We used the temporal summation threshold (TST) of the lower limb nociceptive withdrawal reflex (NWR) and the related pain sensation to study in parallel the time-course of the effect of the GTN administration on the pain processing at spinal level in migraine and healthy subjects. Twenty-eight (21 F; 7M; mean age 34.2±8.2) migraine and 15 (11 F; 4M; mean age 35.9±8.9) healthy subjects were recruited in a double-blind, placebo-controlled, cross-over trial. Neurophysiological examinations were carried out before (baseline) and 30′, 60′, 120′, 180′ and 240′ after GTN (0.9mg sublingual) or placebo administration during two different sessions. In migraineurs, GTN administration was associated to a significant facilitation in temporal summation of pain (reduced TST and increased painful sensation) 60′, 120′ and 180′ after drug intake when compared to baseline, to placebo condition and to controls after GTN intake. Furthermore, in migraineurs who developed migraine after GTN, a significant facilitation in temporal summation of pain was detected 60′, 120′ and 180′ after drug intake when compared to patients without clinical response. In migraineurs the susceptibility to develop migraine attack after GTN administration seems to be a specific trait of a subgroup of patients linked to a supersensitivity of the pain system to GTN. [Copyright &y& Elsevier]

People with Parkinson's disease (PD) often have a posture characterized by lateral trunk flexion poorly responsive to antiparkinsonian drugs. To examine the effects of a rehabilitation programme (daily individual 90-minute-sessions, 5-days-a-week for 4-consecutive weeks) on lateral trunk flexion and mobility, 22 PD patients with mild to severe lateral trunk flexion, and 22 PD patients without trunk flexion were studied. Patients were evaluated using the Unified Parkinson's Disease Rating Scale motor subscale (UPDRS-III) score, and the kinematic behavior of the trunk was recorded by means of an optoelectronic system to determine: a) trunk flexion, inclination and rotation values in the erect standing posture; b) ranges of trunk flexion and inclination during trunk movements. After the treatment, significant decreases in trunk flexion [24°(4) vs. 14°(3), P < 0.001] and inclination in the static condition [23°(5) vs. 12°(4), P < 0.001)] were observed, both of which were maintained at the 6-month follow up. During the trunk flexion task, a significantly increased range of trunk flexion [64°(15) vs. 83°(15), P < 0.001] was observed; similarly, during the lateral bending task, the range of trunk inclination was found to be significantly increased, both toward the side of the trunk deviation [29°(8) vs. 42°(13), P < 0.01] and toward the contralateral side [14°(6) vs 29°(11), P < 0.01]. No further significant changes were observed at the 6-month follow-up. Trunk flexion and inclination values in the upright standing posture correlated slightly with the UPDRS-III score. Our findings show that significant improvements in axial posture and trunk mobility can be obtained through the 4-week rehabilitation programme described, with a parallel improvement in clinical status. © 2010 Movement Disorder Society [ABSTRACT FROM AUTHOR]

We propose a novel electroencephalographic application of a recently developed cerebral source extraction method (Functional Source Separation, FSS), which starts from extracranial signals and adds a functional constraint to the cost function of a basic independent component analysis model without requiring solutions to be independent. Five ad-hoc functional constraints were used to extract the activity reflecting the temporal sequence of sensory information processing along the somatosensory pathway in response to the separate left and right median nerve galvanic stimulation. Constraints required only the maximization of the responsiveness at specific latencies following sensory stimulation, without taking into account that any frequency or spatial information. After source extraction, the reliability of identified FS was assessed based on the position of single dipoles fitted on its retroprojected signals and on a discrepancy measure. The FS positions were consistent with previously reported data (two early subcortical sources localized in the brain stem and thalamus, the three later sources in cortical areas), leaving negligible residual activity at the corresponding latencies. The high-frequency component of the oscillatory activity (HFO) of the extracted component was analyzed. The integrity of the low amplitude HFOs was preserved for each FS. On the basis of our data, we suggest that FSS can be an effective tool to investigate the HFO behavior of the different neuronal pools, recruited at successive times after median nerve galvanic stimulation. As FSs are reconstructed along the entire experimental session, directional and dynamic HFO synchronization phenomena can be studied. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

In the present study we investigated the probability, latency and duration of the inhibitory component of the withdrawal reflex elicited by painful electrical stimulation of the index finger in humans. The stimulus consisted of a train of high-intensity pulses. The investigation was carried out in several upper limb muscles during isometric contractions of different strengths and during a motor sequence consisting of reaching, picking up and transporting an object. We used a new algorithm to detect and characterize the inhibitory reflex. The reflex was found in all muscles except the brachioradialis at all the isometric contraction strengths, and showed a distal-to-proximal gradient of latency and duration. Conversely, during movement the reflex probability was high (> 80%) in the anterior deltoid and triceps muscles during reaching, in the extensor carpi radialis muscle during transporting of the object, and in the first interosseous muscle during both picking up and transporting of the object. This modulation of inhibitory reflex transmission in the upper limb muscles suggests that the motor response is organized in such a way as to inhibit the overall ongoing motor task by interrupting motion during reaching and by releasing the object during transporting. This pattern of modulation appears to differ markedly from that previously reported for the excitatory component of the withdrawal reflex. Study of the nociceptive inhibitory reflexes during movement offers new and more profound insights into the functional anatomical organization of the spinal interneuronal network mediating sensory–motor integration. [ABSTRACT FROM AUTHOR]

Trigemino-cervical reflexes (TCRs) are multisynaptic neck muscle withdrawal responses that are clearly identifiable in humans. Mediated by neural circuits at brainstem level, these reflex responses have been found to be significantly impaired in patients with Parkinson's disease (PD), and it has been hypothesized that a degeneration of brainstem neural structures could play a role in these abnormalities. Because extensive neuronal degeneration at brainstem level has been demonstrated in progressive supranuclear palsy (PSP), in this pilot study we evaluated the TCR responses in 12 subjects with PSP, and in 16 healthy controls. The TCRs were absent in 11 out of the 12 PSP patients while clear responses were evoked in all the healthy subjects. These findings indicate that PSP patients are unable to react to the painful stimuli to the face, suggesting a generalized impairment of the brainstem circuits mediating TCRs. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

We describe a patient who presented myoclonus in the left scapula 3 months after a traumatic lesion of the left long thoracic nerve. Myoclonic activity was recorded as pseudorhythmic electromyographic bursts repeated at a frequency of 2 to 4 Hz, each lasting between 100 and 200 msec, in the left serratus-dorsalis muscle region, trapezius, and deltoid muscles. A combination of peripheral and central mechanisms may have induced the myoclonus in this case. © 2005 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Objective.—To evaluate trigemino-cervical-spinal reflexes (TCSRs) in a group of migraine patients during the pain-free period. Background.—TCRSs are part of a complex nocifensive response involving the cervical and the upper limb muscles, and are modulated by supraspinal inhibitory pathways; it may, thus, be possible to use TCRSs to explore the trigeminal system in migraineurs. Methods.—A total of 43 migraine patients without aura (MWoA, 32 patients) or with typical aura (MWA, 11 patients) and 30 age- and sex-matched healthy subjects took part in the study. TCRSs were obtained by stimulating the supraorbital nerve and recorded from the semispinalis capitis muscle and the biceps brachii. The latency (L, msec), area (A, mVms) and recovery cycle of the reflexes were recorded. The effects of heterotopic painful stimulation on the neurophysiological parameters were studied by a validated cold pressor test (CPT). Results.—No significant changes were found between either migraine patients and controls or MWoA and MWA patients in the mean values in the L and A of TCRSs ( t-test, P > .05). The recovery curve of the trigemino-cervical reflexes (TCRs) was significantly faster in migraine patients than in controls, while no differences were found in the trigemino-spinal reflexes (TSRs) ( t-test, P < .01). Activation of the diffuse inhibitory controls through the CPT induced a significant reduction in the TCRs and TSRs area in both migraine patients and controls (paired t-test, P < .01), though the extent of this reduction did not differ significantly between migraineurs and controls ( t-test, P > .05). Comments.—Our data suggest that the pain-free period in migraine patients is characterized by a hyperexcitability of the trigeminal pathways and of their anatomical and functional connections with the upper cervical cord neurons, and that this abnormal hyperexcitability does not appear to be due to a lack of a supraspinal inhibitory modulation. ( Headache 2005;45:1061-1068) [ABSTRACT FROM AUTHOR]

Many studies have addressed practice effects in motor sequences in Parkinson's disease (PD). Most studied short-term practice and showed that treated patients with mild-to-moderate disease achieve normal or slightly abnormal improvement. Less attention has focused on practice effects after prolonged training (days), and the results are inconclusive. Here, we studied the kinematic changes induced by prolonged practice in a group of medicated patients with mild-to-moderate PD and a healthy control group. We did so by analyzing an internally determined sequential arm movement performed as fast and accurately as possible before and after a 2-week training period. After 1-day's practice, movement duration, pause duration, and movement accuracy improved similarly in patients and controls, indicating that patients benefitted normally from short-term practice. After 1-week's practice, movement and pause duration improved further in both groups, whereas movement accuracy remained unchanged. After 2-weeks' practice, healthy controls continued to improve but patients did not, indicating reduced prolonged practice benefit in PD. Because short-term practice benefit on motor performance is thought to be mediated predominantly by cerebellar activation, whereas long-term practice benefit relies predominantly on the basal ganglia, we attribute our findings to the underlying basal ganglia dysfunction in PD. Our study may be relevant for planning and executing rehabilitation programs in these patients. © 2004 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Benign exertional headache is coded as a separate entity within the International Headache Society's classification system, but the pathophysiological mechanisms underlying this clinical headache subtype are unknown and possibly are similar to those generating migraine. Coexistence of migraine and benign exertional headache in the same patient is not unusual, and antimigraine pharmacologic treatments are often effective in both headache types. Regardless, optimal management mandates that the clinician exclude any intracranial or systemic disease that could mimic “primary” exertional headache. The same holds for primary headaches induced by coughing or sneezing; congenital malformations or neoplasms, particularly within the posterior fossa, are not rare in these patients. The neurologic examination may not be sufficiently sensitive to detect the offending lesion. We describe a patient with migraine without aura and exertional secondary headache due to Chiari malformation type I whose headaches responded to treatment with propranolol and indomethacin. [ABSTRACT FROM AUTHOR]

We analyzed a population of juvenile Huntington disease (HD) subjects of Italian origin (n = 57). The main aim of this study was to analyze the gender effect of the affected parent on age at onset and clinical presentation of offspring with juvenile HD. We also analyzed molecular features of the disease, including CAG mutation length and GluR6 gene polymorphism, according to the affected parent's gender. The mutation length was longer in paternally than in maternally transmitted HD juvenile patients (P = 0.025), nevertheless a similar mean early onset in the two groups (P > 0.05). This data was even enforced by that obtained from the whole cohort of patients included in the databank (n = 600) where, in the presence of increased mean parent-child CAG repeat change in paternal vs. maternal meiotic transmissions (+7.3 vs. +0.7 CAG, P = 0.0002), the mean parent-child year-of-onset change was similar in the two groups (-10.4 and -7.0 years, P > 0.05). A lower TAA-triplet in GluR6 was associated with an earlier age at onset in juvenile patients (P = 0.031, R2 = 0.10). When we added the GluR6 effect on age at onset to the CAG expanded number effect (P = 0.0001, R2 = 0.68) by multiple regression approach, the coefficient of determination R2 increased to 0.81. This effect in addition to the expanded CAG repeat number, found in juvenile and not in adult patients, was slightly enforced by paternal compared to maternal transmissions (R2=0.82). Our findings suggest the occurrence of a weaker effect of the paternal mutation on juvenile age at onset in our population, possibly amplified by other genetic factors, such as the TAA-triplet length in the GluR6 gene., (Copyright 2003 Wiley-Liss, Inc.)