225 research outputs found

    The Clinical Differentiation of Cerebellar Infarction from Common Vertigo Syndromes

    Get PDF
    This article summarizes the emergency department approach to diagnosing cerebellar infarction in the patient presenting with vertigo. Vertigo is defined and identification of a vertigo syndrome is discussed. The differentiation of common vertigo syndromes such as benign paroxysmal positional vertigo, Meniere’s disease, migrainous vertigo, and vestibular neuritis is summarized. Confirmation of a peripheral vertigo syndrome substantially lowers the likelihood of cerebellar infarction, as do indicators of a peripheral disorder such as an abnormal head impulse test. Approximately 10% of patients with cerebellar infarction present with vertigo and no localizing neurologic deficits. The majority of these may have other signs of central vertigo, specifically direction-changing nystagmus and severe ataxia

    Migraines Are Correlated with Higher Levels of Nitrate-, Nitrite-, and Nitric Oxide-Reducing Oral Microbes in the American Gut Project Cohort.

    Get PDF
    Nitrates, such as cardiac therapeutics and food additives, are common headache triggers, with nitric oxide playing an important role. Facultative anaerobic bacteria in the oral cavity may contribute migraine-triggering levels of nitric oxide through the salivary nitrate-nitrite-nitric oxide pathway. Using high-throughput sequencing technologies, we detected observable and significantly higher abundances of nitrate, nitrite, and nitric oxide reductase genes in migraineurs versus nonmigraineurs in samples collected from the oral cavity and a slight but significant difference in fecal samples. IMPORTANCE Recent work has demonstrated a potentially symbiotic relationship between oral commensal bacteria and humans through the salivary nitrate-nitrite-nitric oxide pathway (C. Duncan et al., Nat Med 1:546-551, 1995, http://dx.doi.org/10.1038/nm0695-546). Oral nitrate-reducing bacteria contribute physiologically relevant levels of nitrite and nitric oxide to the human host that may have positive downstream effects on cardiovascular health (V. Kapil et al., Free Radic Biol Med 55:93-100, 2013, http://dx.doi.org/10.1016/j.freeradbiomed.2012.11.013). In the work presented here, we used 16S rRNA Illumina sequencing to determine whether a connection exists between oral nitrate-reducing bacteria, nitrates for cardiovascular disease, and migraines, which are a common side effect of nitrate medications (U. Thadani and T. Rodgers, Expert Opin Drug Saf 5:667-674, 2006, http://dx.doi.org/10.1517/14740338.5.5.667)

    meso-4,5-Diphenyl­imidazolidin-2-one

    Get PDF
    The crystal structure determination of the title compound, C15H14N2O, confirms the cis relationship between the phenyl groups at the 4- and 5-positions on the imidazolidine ring. The dihedral angle between the two phenyl rings is 48.14 (6)°. In the crystal structure, inter­molecular N—H⋯O hydrogen bonds link mol­ecules into centrosymmetric dimers. These dimers are, in turn, linked into a two-dimensional network via weak N—Hâ‹ŻÏ€(arene) inter­actions and π–π stacking inter­actions with centroid–centroid distances of 3.6937 (11) Å

    Dynamic Assessment of Binocular Eye Movement Coordination: Norms and Functional Implications

    Get PDF
    Alignment of the two eyes is controlled by a finely tuned, fast acting system with components within the brain. Assessment of binocular alignment has classically been done statically. Eye positions are assessed in primary position and at eccentric angles to interpret the functional status of the oculomotor nerves and muscles. However, assessment of dynamic eye alignment, the coordination of the eyes during eye movements, has been less commonly carried out and has not been formalized with population norms. Clinicians are aware of slow eye movement dynamic alignment changes, such as that clinically observed in Intranuclear Ophthalmoplegia. But assessment of eye alignment during rapid eye movements, such as saccade or pursuit has not been part of neuro-ophthalmologic assessment. With the advent of inexpensive, high resolution recording systems, both eyes can be simultaneously recorded and their coordination during movement compared. Thus, we now have an opportunity to provide a laboratory based objective measurement of a gamut of binocular coordination systems. Recent research in humans has demonstrated increased variability of binocular coordination during divided attention. Variability is an interesting statistic that can be sensitively assessed in the velocity domain without extensive gaze position recalibration procedures during recording over long intervals. Variability can thus be used as a robust, long-term eye movement parameter with minimal intrusiveness to the subject. It is proposed that population studies of binocular coordination during eye movements be carried out to determine neurologic norms so that conditions such as brain injury and others can be assessed with a functional tool with objective parameters

    Tiimin yhteisöohjautuvuutta haastavat tekijÀt yksityisessÀ organisaatiossa

    Get PDF
    TĂ€mĂ€ tutkimus kĂ€sittelee tiimin yhteisöohjautuvuutta ja sen toteutumista haastavia tekijöitĂ€ yksityisessĂ€ organisaatiossa. TyöelĂ€mĂ€n jatkuvan ja nopeutuvan muutoksen takia, organisaatiot ovat alkaneet kĂ€yttĂ€mÀÀn erilaisia joustavuutta tukevia toimintatapoja kuten tiimien yhteisöohjautuvuutta. TĂ€ssĂ€ tutkimuksessa tiimin yhteisöohjautuvuus mÀÀritellÀÀn tiimin yhteiseksi toiminnaksi, jossa tiimi toimii itsenĂ€isesti ilman esihenkilön kontrollointia tai ohjausta. Hierarkian madaltaminen ja yhteisöohjautuvuuden lisÀÀminen on iso ja aikaa vievĂ€ muutos varsinkin isossa organisaatiossa eikĂ€ tiimien yhteisöohjautuvuuden toteuttaminen ole yksinkertaista. Tutkimuksessa pyritÀÀn vastaamaan kysymykseen ”MinkĂ€laiset asiat haastavat tai estĂ€vĂ€t tiimin yhteisöohjautuvuuden toteutumista?” Tutkimus toteutettiin laadullisena tutkimuksena, sillĂ€ tutkimuksen tavoitteena on pyrkiĂ€ ymmĂ€rtĂ€mÀÀn yhteisöohjautuvuutta ilmiönĂ€ ja siihen liittyviĂ€ kokemuksia. Tutkimuksen aineisto kerĂ€ttiin haastattelemalla yksityisen organisaation kolmea työntekijÀÀ kolmesta eri tiimistĂ€. Haastattelut toteutettiin teemahaastatteluina. Haastatteluaineisto analysoitiin kĂ€yttĂ€mĂ€llĂ€ teoriaohjaavaa sisĂ€llönanalyysia, sillĂ€ teoria ohjasi muun muassa teemahaastattelurungon laadintaa. Tutkimuksessa saatiin selville, ettĂ€ organisaatiossa tiimin yhteisöohjautuvuuden toteutumista haastaa tukitoimintojen riittĂ€mĂ€ttömyys, heikko palautteenantokulttuuri, tiimin sisĂ€iset ongelmat sekĂ€ tehokkaan viestintĂ€jĂ€rjestelmĂ€n puuttuminen. Aineiston mukaan organisaation epĂ€selkeĂ€ viestintĂ€ sekĂ€ viestinnĂ€n toimimattomuus tekevĂ€t ajan tasalla pysymisestĂ€ haastavaa. Tukitoimintojen riittĂ€mĂ€ttömyys ilmenee resurssien puutteena ja esihenkilön tuen riittĂ€mĂ€ttömyytenĂ€. LisĂ€ksi palautteenantokulttuuriin heikkous vaikuttaa tiimin ja yksilön oppimiseen. Tiimin sisĂ€isiĂ€ ongelmia aiheuttavat puolestaan yksilötason erot itseohjautuvuudessa, yhteisöllisyyden puute ja pelisÀÀntöjen puuttuminen. Tutkimustulosten perusteella tiimin yhteisöohjautuvuutta haastavia tekijöitĂ€ ilmenee yksilö-, tiimi- sekĂ€ organisaatiotasolla. LisĂ€ksi haastavat tekijĂ€t vaikuttavat jossain mÀÀrin toisiinsa. Tiimin yhteisöohjautuvuutta haastaviin tekijöihin on siis kiinnitettĂ€vĂ€ laajasti huomiota jokaisella organisaation tasolla. Tulosten perusteella voidaan myös pÀÀtellĂ€, ettĂ€ muutos on organisaatiossa vielĂ€ osittain kesken. Mahdollisena jatkotutkimusaiheena voisi olla laajempi tutkimus tiimin yhteisöohjautuvuutta haastavista tekijöistĂ€ kohdeorganisaatiossa, jolloin saataisiin laajemman joukon kokemuksia ilmiöistĂ€. LisĂ€ksi olisi kiinnostavaa tutkia esihenkilöiden kokemuksia yhteisöohjautuvuudesta, sillĂ€ muutos on vaikuttanut keskeisesti myös esihenkilöiden rooliin

    Stabilized NADH as a Countermeasure for Jet Lag

    Get PDF
    Current remedies for jet lag (phototherapy, melatonin, stimulant, and sedative medications) are limited in efficacy and practicality. The efficacy of a stabilized, sublingual form of reduced nicotin amide adenine dinucleotide (NADH, ENADAlert, Menuco Corp.) as a countermeasure for jet lag was examined. Because NADH increases cellular production of ATP and facilitates dopamine synthesis, it may counteract the effects of jet lag on cognitive functioning and sleepiness. Thirty-five healthy, employed subjects participated in this double-blind, placebo-controlled study. Training and baseline testing were conducted on the West Coast before subjects flew overnight to the East Coast, where they would experience a 3-hour time difference. Upon arrival, individuals were randomly assigned to receive either 20 mg of sublingual stabilized ADH (n=18) or identical placebo tablets (n=17). All participants completed computer-administered tests (including CogScreen7) to assess changes in cognitive functioning, mood, and sleepiness in the morning and afternoon. Jet lag resulted in increased sleepiness for over half the participants and deterioration of cognitive functioning for approximately one third. The morning following the flight, subjects experienced lapses of attention in addition to disruptions in working memory, divided attention, and visual perceptual speed. Individuals who received NADH performed significantly better on 5 of 8 cognitive and psychomotor test measures (P less than or equal to 0.5) and showed a trend for better performance on the other three measures (P less than or equal to .l0). Subjects also reported less sleepiness compared with those who received placebo. No adverse effects were observed with NADH treatment. Stabilized NADH significantly reduced jet lag-induced disruptions of cognitive functioning, was easily administered, and was found to have no adverse side effects

    Novice Driver Training Results and Experience with a PC Based Simulator

    Get PDF
    This paper reports on work accomplished subsequent to a pilot study that was presented at the 2001 conference. This current study will eventually involve the training of over 500 novice drivers, and subsequent comparison of real-world accident and violation rates of the simulator trained group with a traditionally trained control group of demographically matched novice drivers. This paper describes the simulator training system and presents some training data for 111 student subjects collected at three sites involving different simulator configurations. These configurations include a desktop system with a single monitor narrow field of view display, a desktop system with wide field of view display and a cab with wide field of view display. The results include performance measures, a measure of simulator sickness and experience involved in implementing driver-training simulators in the high school environment

    The effect of prolonged monocular occlusion on latent nystagmus in the treatment of amblyopia

    Get PDF
    We recorded eye movements in 5 patients with latent nystagmus (LN) before and after 2 days of occlusion of the better eye. The slow-phase speed of the nystagmus (SPS) was in general, before occlusion, lower when the better eye fixated but, after occlusion, lower when the worse eye fixated. However, the sum of SPS during right fixation and SPS during left fixation remained constant. Oscillopsia complaints gradually disappeared during the period of occlusion. These findings indicate that the difference between the SPS during fixation with the right eye and the SPS during fixation with the left eye in LN patients is caused by a compensatory drift that decreases LN during fixation with the better eye but increases LN during fixation with the worse eye. During occlusion, this compensatory drift changes its direction and magnitude slowly over days. Hence, occlusion of the better eye in children with amblyopia and LN should be prescribed only in days per week, not in hours per day

    Automatic mental processes, automatic actions and behaviours in game transfer phenomena: an empirical self-report study using online forum data

    Get PDF
    Previous studies have demonstrated that the playing of videogames can have both intended and unintended effects. The purpose of this study was to investigate the influence of videogames on players’ mental processes and behaviours in day-to-day settings. A total of 1,023 self-reports from 762 gamers collected from online videogame forums were classified, quantified, described and explained. The data include automatic thoughts, sensations and impulses, automatic mental replays of the game in real life, and voluntary/involuntary behaviours with videogame content. Many gamers reported that they had responded – at least sometimes – to real life stimuli as if they were still playing videogames. This included overreactions, avoidances, and involuntary movements of limbs. These experiences lasted relatively short periods of time but in a minority of players were recurrent. The gamers' experiences appeared to be enhanced by virtual embodiment, repetitive manipulation of game controls, and their gaming habits. However, similar phenomena may also occur when doing other non-gaming activities. The implications of these game transfer experiences are discussed
    • 

    corecore