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Find video protocols related to scientific articles indexed in Pubmed.
[Valproate can induce reversible encephalopathy.]
Ugeskr. Laeg.
PUBLISHED: 11-15-2014
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Valproate (VPA) is a widely used antiepileptic drug - also in the elderly. A female patient was diagnosed with epilepsy at the age of 60 years and treated with VPA for 16 years before developing tremor, rigidity, cognitive impairment and descending consciousness progressing to coma. After discontinuation of VPA she regained full consciousness, could talk and feed herself. The extrapyramidal and cognitive symptoms completely subsided during the following months. VPA-induced encephalopathy is an uncommon but serious adverse effect that should be considered in patients with cognitive decline during VPA treatment.
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Biophysics of directional hearing in the American alligator (Alligator mississippiensis).
J. Exp. Biol.
PUBLISHED: 03-28-2014
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Physiological and anatomical studies have suggested that alligators have unique adaptations for spatial hearing. Sound localization cues are primarily generated by the filtering of sound waves by the head. Different vertebrate lineages have evolved external and/or internal anatomical adaptations to enhance these cues, such as pinnae and interaural canals. It has been hypothesized that in alligators, directionality may be enhanced via the acoustic coupling of middle ear cavities, resulting in a pressure difference receiver (PDR) mechanism. The experiments reported here support a role for a PDR mechanism in alligator sound localization by demonstrating that (1) acoustic space cues generated by the external morphology of the animal are not sufficient to generate location cues that match physiological sensitivity, (2) continuous pathways between the middle ears are present to provide an anatomical basis for coupling, (3) the auditory brainstem response shows some directionality, and (4) eardrum movement is directionally sensitive. Together, these data support the role of a PDR mechanism in crocodilians and further suggest this mechanism is a shared archosaur trait, most likely found also in the extinct dinosaurs.
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Hearing loss in relation to sound exposure of professional symphony orchestra musicians.
Ear Hear
PUBLISHED: 03-08-2014
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The objectives of this study were to: (1) estimate the hearing status of classical symphony orchestra musicians and (2) investigate the hypothesis that occupational sound exposure of symphony orchestra musicians leads to elevated hearing thresholds.
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A user-operated audiometry method based on the maximum likelihood principle and the two-alternative forced-choice paradigm.
Int J Audiol
PUBLISHED: 02-10-2014
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To create a user-operated pure-tone audiometry method based on the method of maximum likelihood (MML) and the two-alternative forced-choice (2AFC) paradigm with high test-retest reliability without the need of an external operator and with minimal influence of subjects' fluctuating response criteria. User-operated audiometry was developed as an alternative to traditional audiometry for research purposes among musicians.
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Spatial hearing in Cope's gray treefrog: II. Frequency-dependent directionality in the amplitude and phase of tympanum vibrations.
J. Comp. Physiol. A Neuroethol. Sens. Neural. Behav. Physiol.
PUBLISHED: 01-22-2014
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Anuran ears function as pressure difference receivers, and the amplitude and phase of tympanum vibrations are inherently directional, varying with sound incident angle. We quantified the nature of this directionality for Cope's gray treefrog, Hyla chrysoscelis. We presented subjects with pure tones, advertisement calls, and frequency-modulated sweeps to examine the influence of frequency, signal level, lung inflation, and sex on ear directionality. Interaural differences in the amplitude of tympanum vibrations were 1-4 dB greater than sound pressure differences adjacent to the two tympana, while interaural differences in the phase of tympanum vibration were similar to or smaller than those in sound phase. Directionality in the amplitude and phase of tympanum vibration were highly dependent on sound frequency, and directionality in amplitude varied slightly with signal level. Directionality in the amplitude and phase of tone- and call-evoked responses did not differ between sexes. Lung inflation strongly affected tympanum directionality over a narrow frequency range that, in females, included call frequencies. This study provides a foundation for further work on the biomechanics and neural mechanisms of spatial hearing in H. chrysoscelis, and lends valuable perspective to behavioral studies on the use of spatial information by this species and other frogs.
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Post-stroke mortality, stroke severity, and preadmission antipsychotic medicine use--a population-based cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
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It has been suggested that antipsychotic medication may be neuroprotective and may reduce post-stroke mortality, but studies are few and ambiguous. We aimed to investigate the post-stroke effects of preadmission antipsychotic use.
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Compression of head-related transfer function using autoregressive-moving-average models and Legendre polynomials.
J. Acoust. Soc. Am.
PUBLISHED: 11-05-2013
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Head-related transfer functions (HRTFs) are generally large datasets, which can be an important constraint for embedded real-time applications. A method is proposed here to reduce redundancy and compress the datasets. In this method, HRTFs are first compressed by conversion into autoregressive-moving-average (ARMA) filters whose coefficients are calculated using Pronys method. Such filters are specified by a few coefficients which can generate the full head-related impulse responses (HRIRs). Next, Legendre polynomials (LPs) are used to compress the ARMA filter coefficients. LPs are derived on the sphere and form an orthonormal basis set for spherical functions. Higher-order LPs capture increasingly fine spatial details. The number of LPs needed to represent an HRTF, therefore, is indicative of its spatial complexity. The results indicate that compression ratios can exceed 98% while maintaining a spectral error of less than 4?dB in the recovered HRTFs.
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Prenatal valproate exposure and risk of autism spectrum disorders and childhood autism.
JAMA
PUBLISHED: 04-25-2013
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Valproate is used for the treatment of epilepsy and other neuropsychological disorders and may be the only treatment option for women of childbearing potential. However, prenatal exposure to valproate may increase the risk of autism.
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Childhood epilepsy and maternal antibodies to microbial and tissue antigens during pregnancy.
Epilepsy Res.
PUBLISHED: 01-17-2013
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Several epidemiologic studies show associations between mothers infections during pregnancy and an increased risk of mental and neurological disorders in the offspring. Such associations could be due to the direct or indirect effects of infectious agents, including immune responses to infectious agents that display molecular mimicry with host antigens. We measured a range of antigen-specific maternal IgG antibodies to examine if any were associated with risk for childhood epilepsy in offspring.
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Middle ear cavity morphology is consistent with an aquatic origin for testudines.
PLoS ONE
PUBLISHED: 01-14-2013
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The position of testudines in vertebrate phylogeny is being re-evaluated. At present, testudine morphological and molecular data conflict when reconstructing phylogenetic relationships. Complicating matters, the ecological niche of stem testudines is ambiguous. To understand how turtles have evolved to hear in different environments, we examined middle ear morphology and scaling in most extant families, as well as some extinct species, using 3-dimensional reconstructions from micro magnetic resonance (MR) and submillimeter computed tomography (CT) scans. All families of testudines exhibited a similar shape of the bony structure of the middle ear cavity, with the tympanic disk located on the rostrolateral edge of the cavity. Sea Turtles have additional soft tissue that fills the middle ear cavity to varying degrees. When the middle ear cavity is modeled as an air-filled sphere of the same volume resonating in an underwater sound field, the calculated resonances for the volumes of the middle ear cavities largely fell within testudine hearing ranges. Although there were some differences in morphology, there were no statistically significant differences in the scaling of the volume of the bony middle ear cavity with head size among groups when categorized by phylogeny and ecology. Because the cavity is predicted to resonate underwater within the testudine hearing range, the data support the hypothesis of an aquatic origin for testudines, and function of the middle ear cavity in underwater sound detection.
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Antidepressant exposure in pregnancy and risk of autism spectrum disorders.
Clin Epidemiol
PUBLISHED: 01-01-2013
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Both the use of antidepressant medication during pregnancy and the prevalence of autism spectrum disorder have increased during recent years. A causal link has recently been suggested, but the association may be confounded by the underlying indication for antidepressant use. We investigated the association between maternal use of antidepressant medication in pregnancy and autism, controlling for potential confounding factors.
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Sound exposure of symphony orchestra musicians.
Ann Occup Hyg
PUBLISHED: 08-12-2011
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Assessment of sound exposure by noise dosimetry can be challenging especially when measuring the exposure of classical orchestra musicians where sound originate from many different instruments. A new measurement method of bilateral sound exposure of classical musicians was developed and used to characterize sound exposure of the left and right ear simultaneously in two different symphony orchestras.
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Prenatal exposure to elevated maternal body temperature and risk of epilepsy in childhood: a population-based pregnancy cohort study.
Paediatr Perinat Epidemiol
PUBLISHED: 04-28-2011
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Elevated maternal body temperature during pregnancy is of clinical concern as side effects have been reported. We estimated the association between maternal fever and sauna bathing during pregnancy and risk of epilepsy in the offspring. We identified 86,810 liveborn singletons from the Danish National Birth Cohort (DNBC) and followed them for up to 9 years of age. Information on fever including number, timing, level, duration, and symptoms of each fever episodes was collected in two computer-assisted telephone interviews around 17 and 32 gestational weeks; information on maternal use of a sauna was collected in the latter interview, and information on epilepsy was obtained from the Danish National Hospital Register. We applied Cox regression models to estimate the incidence rate ratios (IRR) of epilepsy for children exposed to maternal fever and sauna bathing during pregnancy. Maternal sauna bathing during pregnancy was not associated with an increased risk of epilepsy. Maternal fever during pregnancy in general was not associated with an increased risk of epilepsy in the offspring [IRR = 1.01, 95% confidence interval (CI) 0.85, 1.19], and no dose-response pattern was found according to number, level and duration of fever. However we did find an increased risk of epilepsy among children exposed to at least 3 fever episodes (IRR = 1.88, 95% CI 1.19, 2.98), to maternal fever with symptoms in the urinary system (IRR = 4.86, 95% CI 1.56, 15.17), and to one-day maternal fever of 39.0-39.4°C (IRR = 2.79, 95% CI 1.60, 4.84). Our findings do not support a strong association between hyperthermia and epilepsy but the associations between underlying causes of fever, especially prenatal infections, call for more research.
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Binaural processing by the gecko auditory periphery.
J. Neurophysiol.
PUBLISHED: 02-16-2011
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Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion in the Tokay gecko with neurophysiological recordings from the auditory nerve. Laser vibrometry shows that their ear is a two-input system with approximately unity interaural transmission gain at the peak frequency (? 1.6 kHz). Median interaural delays are 260 ?s, almost three times larger than predicted from gecko head size, suggesting interaural transmission may be boosted by resonances in the large, open mouth cavity (Vossen et al. 2010). Auditory nerve recordings are sensitive to both interaural time differences (ITD) and interaural level differences (ILD), reflecting the acoustical interactions of direct and indirect sound components at the eardrum. Best ITD and click delays match interaural transmission delays, with a range of 200-500 ?s. Inserting a mold in the mouth cavity blocks ITD and ILD sensitivity. Thus the neural response accurately reflects tympanic directionality, and most neurons in the auditory pathway should be directional.
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Temporally selective processing of communication signals by auditory midbrain neurons.
J. Neurophysiol.
PUBLISHED: 02-02-2011
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Perception of the temporal structure of acoustic signals contributes critically to vocal signaling. In the aquatic clawed frog Xenopus laevis, calls differ primarily in the temporal parameter of click rate, which conveys sexual identity and reproductive state. We show here that an ensemble of auditory neurons in the laminar nucleus of the torus semicircularis (TS) of X. laevis specializes in encoding vocalization click rates. We recorded single TS units while pure tones, natural calls, and synthetic clicks were presented directly to the tympanum via a vibration-stimulation probe. Synthesized click rates ranged from 4 to 50 Hz, the rate at which the clicks begin to overlap. Frequency selectivity and temporal processing were characterized using response-intensity curves, temporal-discharge patterns, and autocorrelations of reduplicated responses to click trains. Characteristic frequencies ranged from 140 to 3,250 Hz, with minimum thresholds of -90 dB re 1 mm/s at 500 Hz and -76 dB at 1,100 Hz near the dominant frequency of female clicks. Unlike units in the auditory nerve and dorsal medullary nucleus, most toral units respond selectively to the behaviorally relevant temporal feature of the rate of clicks in calls. The majority of neurons (85%) were selective for click rates, and this selectivity remained unchanged over sound levels 10 to 20 dB above threshold. Selective neurons give phasic, tonic, or adapting responses to tone bursts and click trains. Some algorithms that could compute temporally selective receptive fields are described.
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Breastfeeding and risk of epilepsy in childhood: a birth cohort study.
J. Pediatr.
PUBLISHED: 01-13-2011
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We asked whether breastfeeding reduces the risk of epilepsy in childhood.
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Sound detection by the longfin squid (Loligo pealeii) studied with auditory evoked potentials: sensitivity to low-frequency particle motion and not pressure.
J. Exp. Biol.
PUBLISHED: 10-19-2010
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Although hearing has been described for many underwater species, there is much debate regarding if and how cephalopods detect sound. Here we quantify the acoustic sensitivity of the longfin squid (Loligo pealeii) using near-field acoustic and shaker-generated acceleration stimuli. Sound field pressure and particle motion components were measured from 30 to 10,000 Hz and acceleration stimuli were measured from 20 to 1000 Hz. Responses were determined using auditory evoked potentials (AEPs) with electrodes placed near the statocysts. Evoked potentials were generated by both stimuli and consisted of two wave types: (1) rapid stimulus-following waves, and (2) slower, high-amplitude waves, similar to some fish AEPs. Responses were obtained between 30 and 500 Hz with lowest thresholds between 100 and 200 Hz. At the best frequencies, AEP amplitudes were often >20 ?V. Evoked potentials were extinguished at all frequencies if (1) water temperatures were less than 8°C, (2) statocysts were ablated, or (3) recording electrodes were placed in locations other than near the statocysts. Both the AEP response characteristics and the range of responses suggest that squid detect sound similarly to most fish, with the statocyst acting as an accelerometer through which squid detect the particle motion component of a sound field. The modality and frequency range indicate that squid probably detect acoustic particle motion stimuli from both predators and prey as well as low-frequency environmental sound signatures that may aid navigation.
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Hearing in the African lungfish (Protopterus annectens): pre-adaptation to pressure hearing in tetrapods?
Biol. Lett.
PUBLISHED: 09-08-2010
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Lungfishes are the closest living relatives of the tetrapods, and the ear of recent lungfishes resembles the tetrapod ear more than the ear of ray-finned fishes and is therefore of interest for understanding the evolution of hearing in the early tetrapods. The water-to-land transition resulted in major changes in the tetrapod ear associated with the detection of air-borne sound pressure, as evidenced by the late and independent origins of tympanic ears in all of the major tetrapod groups. To investigate lungfish pressure and vibration detection, we measured the sensitivity and frequency responses of five West African lungfish (Protopterus annectens) using brainstem potentials evoked by calibrated sound and vibration stimuli in air and water. We find that the lungfish ear has good low-frequency vibration sensitivity, like recent amphibians, but poor sensitivity to air-borne sound. The skull shows measurable vibrations above 100 Hz when stimulated by air-borne sound, but the ear is apparently insensitive at these frequencies, suggesting that the lungfish ear is neither adapted nor pre-adapted for aerial hearing. Thus, if the lungfish ear is a model of the ear of early tetrapods, their auditory sensitivity was limited to very low frequencies on land, mostly mediated by substrate-borne vibrations.
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Analytical model of internally coupled ears.
J. Acoust. Soc. Am.
PUBLISHED: 08-17-2010
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Lizards and many birds possess a specialized hearing mechanism: internally coupled ears where the tympanic membranes connect through a large mouth cavity so that the vibrations of the tympanic membranes influence each other. This coupling enhances the phase differences and creates amplitude differences in the tympanic membrane vibrations. Both cues show strong directionality. The work presented herein sets out the derivation of a three dimensional analytical model of internally coupled ears that allows for calculation of a complete vibration profile of the membranes. The analytical model additionally provides the opportunity to incorporate the effect of the asymmetrically attached columella, which leads to the activation of higher membrane vibration modes. Incorporating this effect, the analytical model can explain measurements taken from the tympanic membrane of a living lizard, for example, data demonstrating an asymmetrical spatial pattern of membrane vibration. As the analytical calculations show, the internally coupled ears increase the directional response, appearing in large directional internal amplitude differences (iAD) and in large internal time differences (iTD). Numerical simulations of the eigenfunctions in an exemplary, realistically reconstructed mouth cavity further estimate the effects of its complex geometry.
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The auditory brainstem response in two lizard species.
J. Acoust. Soc. Am.
PUBLISHED: 08-17-2010
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Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform in response to click stimulation showed one prominent and several smaller peaks occurring within 10 ms of the stimulus onset. ABRs to brief tone bursts revealed that geckos and anoles were most sensitive between 1.6-2 kHz and had similar hearing sensitivity up to about 5 kHz (thresholds typically 20-50 dB SPL). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than in most bird species.
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Vertebrate pressure-gradient receivers.
Hear. Res.
PUBLISHED: 08-10-2010
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The eardrums of all terrestrial vertebrates (tetrapods) are connected through Eustachian tubes or interaural canals. In some of the animals, these connections create pressure-gradient directionality, an enhanced directionality by interaction of sound arriving at both sides of the eardrum and strongly dependent on interaural transmission attenuation. Even though the tympanic middle ear has originated independently in the major tetrapod groups, in each group the ancestral condition probably was that the two middle ears were exposed in the mouth cavity with relatively high interaural transmission. Recent vertebrates form a continuum from perfect interaural transmission (0 dB in a certain frequency band) and pronounced eardrum directionality (30-40 dB) in the lizards, over somewhat attenuated transmission and limited directionality in birds and frogs, to the strongly attenuated interaural transmission and functionally isolated pressure receiver ears in the mammals. Since some of the binaural interaction already takes place at the eardrum in animals with strongly coupled ears, producing enhanced interaural time and level differences, the subsequent neural processing may be simpler. In robotic simulations of lizards, simple binaural subtraction (EI cells, found in brainstem nuclei of both frogs and lizards) produces strongly lateralized responses that are sufficient for steering the animal robustly to sound sources.
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Gestational age, birth weight, and risk for injuries in childhood.
Epidemiology
PUBLISHED: 06-30-2010
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Some children experience more injuries than others due to personal or environmental risk factors, or to chance. Most injury studies have focused on proximal causes; few have examined the role of neonatal characteristics such as birth weight and gestational age.
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Intake of marine n-3 fatty acids during pregnancy and risk for epilepsy in the offspring: a population-based cohort study.
Epilepsy Res.
PUBLISHED: 03-25-2010
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To estimate if maternal intake of n-3 long-chain polyunsaturated fatty acids (LCPUFA) during pregnancy is related to the risk of epilepsy in the offspring.
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Prenatal stress and cerebral palsy: a nationwide cohort study in Denmark.
Psychosom Med
PUBLISHED: 05-29-2009
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Exposure to prenatal stress may affect neurodevelopment of the fetus, but whether this exposure increases the risk of cerebral palsy (CP) later in life is unknown. We aimed to examine the association between maternal bereavement during the prenatal time period and CP in childhood.
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A nationwide study on the risk of autism after prenatal stress exposure to maternal bereavement.
Pediatrics
PUBLISHED: 04-02-2009
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Prenatal stress has been linked to several adverse neurobehavioral outcomes, which may share a common pathophysiology with autism. We aimed to examine whether prenatal stress exposure after maternal bereavement is associated with an increased risk of autism later in life.
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Long-term risk of epilepsy after traumatic brain injury in children and young adults: a population-based cohort study.
Lancet
PUBLISHED: 02-21-2009
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The risk of epilepsy shortly after traumatic brain injury is high, but how long this high risk lasts is unknown. We aimed to assess the risk of epilepsy up to 10 years or longer after traumatic brain injury, taking into account sex, age, severity, and family history.
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Prenatal stress and risk of febrile seizures in children: a nationwide longitudinal study in Denmark.
J Autism Dev Disord
PUBLISHED: 02-20-2009
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We aimed to examine whether exposure to prenatal stress following maternal bereavement is associated with an increased risk of febrile seizures. In a longitudinal population-based cohort study, we followed 1,431,175 children born in Denmark. A total of 34,777 children were born to women who lost a close relative during pregnancy or within 1 year before the pregnancy and they were included in the exposed group. The exposed children had a risk of febrile seizures similar to that of the unexposed children (hazard ratio (HR) 1.00, 95% CI 0.94-1.06). The HRs did not differ according to the nature or timing of bereavement. Our data do not suggest any causal link between exposure to prenatal stress and febrile seizures in childhood.
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Binge drinking during pregnancy and risk of seizures in childhood: a study based on the Danish National Birth Cohort.
Am. J. Epidemiol.
PUBLISHED: 02-10-2009
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Seizures are often found in children with fetal alcohol syndrome, but it is not known whether binge drinking during pregnancy by nonalcoholic women is associated with an increased risk of seizure disorders in children. The authors conducted a population-based cohort study of 80,526 liveborn singletons in the Danish National Birth Cohort (1996-2002). Information on maternal binge drinking (intake of > or = 5 drinks on a single occasion) was collected in 2 computer-assisted telephone interviews during pregnancy. Children were followed for up to 8 years. Information on neonatal seizures, epilepsy, and febrile seizures was retrieved from the Danish National Hospital Register. Results showed that exposure to binge drinking episodes during pregnancy was not associated with an increased risk of seizure disorders in children, except for those exposed at 11-16 gestational weeks. These children had a 3.15-fold increased risk of neonatal seizures (95% confidence interval: 1.37, 7.25) and a 1.81-fold increased risk of epilepsy (95% confidence interval: 1.13, 2.90). These findings suggest that maternal binge drinking during a specific time period of pregnancy may be associated with an increased risk of specific seizure disorders in the offspring. The results are exploratory, however, and need to be replicated.
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Register-based studies on febrile seizures in Denmark.
Brain Dev.
PUBLISHED: 02-08-2009
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During a short period of brain development, one out of 25 children experience seizures when exposed to fever. The risk and consequences of these febrile seizures remain incompletely understood. We have conducted a number of studies within a population-based cohort of 1.6 million children born in Denmark (1977-2004). We constructed the cohort by linking registers on civil service, health, and cause of death. We followed the cohort for up to 28 years with virtually no loss to follow-up. The aetiology of febrile seizures depends on a genetic susceptibility that can be transmitted through both parents. The risk of febrile seizures increases with decreasing birth weight and gestational age at birth indicating that pre- and perinatal risk factors play a causal role. Measles, mumps, and rubella vaccination increases the risk of febrile seizures for two weeks, but the absolute risk is small even in high-risk children. Febrile seizure is associated with an increased risk of epilepsy and the risk remained high well into adulthood. The risk of epilepsy is particular high for persons with cerebral palsy, low Apgar scores, or a family history of epilepsy. The risk of schizophrenia is slightly increased among persons with a history of febrile seizures even in persons without epilepsy, but the association need not be causal and more studies are needed. Febrile seizure is a common condition with a benign outcome for the vast majority of children. Genes and environmental factors operating in early life seem to play a causal role.
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Traumatic brain injury: risks of epilepsy and implications for medicolegal assessment.
Epilepsia
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Traumatic brain injury (TBI) is a potentially preventable cause of epilepsy. Increasing incidence among army personnel and the high incidence among children and young people raise concern. This article presents a review of selected studies dealing with the risks of TBI and the risk of posttraumatic epilepsy in humans. The incidence of persons admitted to hospital with TBI has decreased in developed countries in recent years. However, there is little change in TBI-associated deaths, and the decrease in hospitalization may merely reflect that more people with head injury are cared for on an outpatient basis. It is clear that epilepsy is a frequent consequence of brain injury, even many years after the injury. However, several well-controlled studies have been unable to identify therapies that prevent the development of epilepsy after TBI. Posttraumatic epilepsy has significant implications for the affected individuals, family, and society. Despite several interventions used to prevent posttraumatic epilepsy, the only proven "intervention" to date is to prevent TBI from occurring.
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Epidemiology of epilepsy in adults: implementing the ILAE classification and terminology into population-based epidemiologic studies.
Epilepsia
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The new proposal for Revised Terminology for Organization of Seizures and Epilepsies published in 2010 poses challenges to all fields of epilepsy including epidemiology. We describe efforts to incorporate the new terminology and classification into population-based health registers in Denmark in order to provide the background for assessment of the quality of epilepsy care, epidemiologic studies of epilepsy, and clinical trials in adults.
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Specialization for underwater hearing by the tympanic middle ear of the turtle, Trachemys scripta elegans.
Proc. Biol. Sci.
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Turtles, like other amphibious animals, face a trade-off between terrestrial and aquatic hearing. We used laser vibrometry and auditory brainstem responses to measure their sensitivity to vibration stimuli and to airborne versus underwater sound. Turtles are most sensitive to sound underwater, and their sensitivity depends on the large middle ear, which has a compliant tympanic disc attached to the columella. Behind the disc, the middle ear is a large air-filled cavity with a volume of approximately 0.5 ml and a resonance frequency of approximately 500 Hz underwater. Laser vibrometry measurements underwater showed peak vibrations at 500-600 Hz with a maximum of 300 µm s(-1) Pa(-1), approximately 100 times more than the surrounding water. In air, the auditory brainstem response audiogram showed a best sensitivity to sound of 300-500 Hz. Audiograms before and after removing the skin covering reveal that the cartilaginous tympanic disc shows unchanged sensitivity, indicating that the tympanic disc, and not the overlying skin, is the key sound receiver. If air and water thresholds are compared in terms of sound intensity, thresholds in water are approximately 20-30 dB lower than in air. Therefore, this tympanic ear is specialized for underwater hearing, most probably because sound-induced pulsations of the air in the middle ear cavity drive the tympanic disc.
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Risk of febrile seizures and epilepsy after vaccination with diphtheria, tetanus, acellular pertussis, inactivated poliovirus, and Haemophilus influenzae type B.
JAMA
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Vaccination with whole-cell pertussis vaccine carries an increased risk of febrile seizures, but whether this risk applies to the acellular pertussis vaccine is not known. In Denmark, acellular pertussis vaccine has been included in the combined diphtheria-tetanus toxoids-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b (DTaP-IPV-Hib) vaccine since September 2002.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.