91 research outputs found
Differences in early and late pattern-onset visual-evoked potentials between self-reported migraineurs and controls
Striped patterns have been shown to induce strong visual illusions and discomforts to migraineurs in previous literature. Previous research has suggested that these unusual visual symptoms to be linked with the hyperactivity on the visual cortex of migraine sufferers. The present study searched for evidence supporting this hypothesis by comparing the visual evoked potentials (VEPs) elicited by striped patterns of specific spatial frequencies (0.5, 3, and 13 cycles-per-degree) between a group of 29 migraineurs (17 with aura/12 without) and 31 non-migraineurs. In addition, VEPs to the same stripped patterns were compared between non-migraineurs who were classified as hyperexcitable versus non-hyperexcitable using a previously established behavioural pattern glare task. We found that the migraineurs had a significantly increased N2 amplitude for stimuli with 13 cpd gratings but an attenuated late negativity (LN: 400 - 500 ms after the stimuli onset) for all the spatial frequencies. Interestingly, non-migraineurs who scored as hyperexcitable appeared to have similar response patterns to the migraineurs, albeit in an attenuated form. We propose that the enhanced N2 could reflect disruption of the balance between parvocellular and magnocellular pathway, which is in support of the cortical hyperexcitation hypothesis in migraineurs. In addition, the attenuation of the late negativity could reflect a top-down feedback mechanism to suppress visual processing of an aversive stimulus
Attenuated alpha oscillation and hyperresponsiveness reveals impaired perceptual learning in migraineurs.
Background: Anomalous phantom visual perceptions coupled to an aversion and discomfort to some visual patterns (especially grating in mid-range spatial frequency) have been associated with the hyperresponsiveness in migraine patients. Previous literature has found fluctuations of alpha oscillation (8-14 Hz) over the visual cortex to be associated with the gating of the visual stream. In the current study, we examined whether alpha activity was differentially modulated in migraineurs in anticipation of an upcoming stimulus as well as post-stimulus periods. Methods: We used EEG to examine the brain activity in a group of 28 migraineurs (17 with aura/11 without) and 29 non-migraineurs and compared their alpha power in the pre/post-stimulus period relative to the onset of stripped gratings. Results: Overall, we found that migraineurs had significantly less alpha power prior to the onset of the stimulus relative to controls. Moreover, migraineurs had significantly greater post-stimulus alpha suppression (i.e event-related desynchronization) induced by the grating in 3 cycles per degree at the 2nd half of the experiment. Conclusions: These findings taken together provide strong support for the presence of the hyperresponsiveness of the visual cortex of migraine sufferers. We speculate that it could be the consequence of impaired perceptual learning driven by the dysfunction of GABAergic inhibitory mechanism
Methods for Assessing the Impact of Fog Oil Smoke on Availability, Palatability, & Food Quality of Relevant Life Stages of Insects for Threatened and Endangered Species
A methodology for quantifying population dynamics and food source value of insect fauna in areas subjected to fog oil smoke was developed. Our approach employed an environmentally controlled re-circulating wind tunnel outfitted with a high-heat vaporization and re-condensation fog oil generator that has been shown to produce aerosols of comparable chemistry and droplet-size distribution as those of field releases of the smoke. This method provides reproducible exposures of insects under realistic climatic and environmental conditions to fog oil aerosols that duplicate chemical and droplet-size characteristics of field releases of the smoke. The responses measured take into account reduction in food sources due to death and to changes in availability of relevant life stages of insects that form the prey base for the listed Threatened and Endangered Species. The influence of key environmental factors, wind speed and canopy structure on these responses were characterized. Data generated using this method was used to develop response functions related to particle size, concentration, wind speed, and canopy structure that will allow military personnel to assess and manage impacts to endangered species from fog oil smoke used in military training
Sequence-Signature Optimization Enables Improved Identification of Human HV6-1-Derived Class Antibodies That Neutralize Diverse Influenza A Viruses
Sequence signatures of multidonor broadly neutralizing influenza antibodies can be used to quantify the prevalence of B cells with virus-neutralizing potential to accelerate development of broadly protective vaccine strategies. Antibodies of the same class share similar recognition modes and developmental pathways, and several antibody classes have been identified that neutralize diverse group 1- and group 2-influenza A viruses and have been observed in multiple human donors. One such multidonor antibody class, the HV6-1-derived class, targets the stem region of hemagglutinin with extraordinary neutralization breadth. Here, we use an iterative process to combine informatics, biochemical, and structural analyses to delineate an improved sequence signature for HV6-1-class antibodies. Based on sequence and structure analyses of known HV6-1 class antibodies, we derived a more inclusive signature (version 1), which we used to search for matching B-cell transcripts from published next-generation sequencing datasets of influenza vaccination studies. We expressed selected antibodies, evaluated their function, and identified amino acid-level requirements from which to refine the sequence signature (version 2). The cryo-electron microscopy structure for one of the signature-identified antibodies in complex with hemagglutinin confirmed motif recognition to be similar to known HV6-1-class members, MEDI8852 and 56.a.09, despite differences in recognition-loop length. Threading indicated the refined signature to have increased accuracy, and signature-identified heavy chains, when paired with the light chain of MEDI8852, showed neutralization comparable to the most potent members of the class. Incorporating sequences of additional class members thus enables an improved sequence signature for HV6-1-class antibodies, which can identify class members with increased accuracy
Paediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2: a case report
Factors associated with nursing home placement of all patients admitted for inpatient rehabilitation in Singapore community hospitals from 1996 to 2005: A disease stratified analysis
10.1371/journal.pone.0082697PLoS ONE812-POLN
TESS discovery of a super-Earth and two sub-Neptunes orbiting the bright, nearby, Sun-like star HD 22946
We report the Transiting Exoplanet Survey Satellite (TESS) discovery of a
three-planet system around the bright Sun-like star HD~22946(V=8.3 mag),also
known as TIC~100990000, located 63 parsecs away.The system was observed by TESS
in Sectors 3, 4, 30 and 31 and two planet candidates, labelled TESS Objects of
Interest (TOIs) 411.01 (planet ) and 411.02 (planet ), were identified on
orbits of 9.57 and 4.04 days, respectively. In this work, we validate the two
planets and recover an additional single transit-like signal in the light
curve, which suggests the presence of a third transiting planet with a longer
period of about 46 days.We assess the veracity of the TESS transit signals and
use follow-up imaging and time series photometry to rule out false positive
scenarios, including unresolved binary systems, nearby eclipsing binaries or
background/foreground stars contaminating the light curves. Parallax
measurements from Gaia EDR3, together with broad-band photometry and
spectroscopic follow-up by TFOP allowed us to constrain the stellar parameters
of TOI-411, including its radius of. Adopting this value,
we determined the radii for the three exoplanet candidates and found that
planet is a super-Earth, with a radius of , while
planet and are sub-Neptunian planets, with radii
of and respectively. By using
dynamical simulations, we assessed the stability of the system and evaluated
the possibility of the presence of other undetected, non-transiting planets by
investigating its dynamical packing. We find that the system is dynamically
stable and potentially unpacked, with enough space to host at least one more
planet between and .(Abridged)Comment: 21 pages, 12 figures. Accepted for publication on A&
A systematic scoping review of approaches to teaching and assessing empathy in medicine
10.1186/s12909-021-02697-6BMC Medical Education21129
Gene Therapy: Charting a Future Course—Summary of a National Institutes of Health Workshop, April 12, 2013
Recently, the gene therapy field has begun to experience clinical successes in a number of different diseases using various approaches and vectors. The workshop Gene Therapy: Charting a Future Course, sponsored by the National Institutes of Health (NIH) Office of Biotechnology Activities, brought together early and mid-career researchers to discuss the key scientific challenges and opportunities, ethical and communication issues, and NIH and foundation resources available to facilitate further clinical advances
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
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