1,701 research outputs found
Neurophysiological and behavioural investigation of the auditory cortico-collicular pathway
One of the key objectives in neuroscience is to understand how the brain processes sensory information to generate perception and guide decisions. Sensory processing has been studied extensively, primarily from a hierarchical perspective with a focus on the processing along ascending pathways. However, ascending sensory pathways are accompanied by descending connections at various levels of processing, yet their contributions to sensory processing remain unclear. In this thesis, I studied one of the major descending circuits in the central auditory system, the cortico-collicular pathway, which connects the auditory cortex (AC) to the auditory midbrain (i.e. the inferior colliculus, IC). To understand the role of this pathway during sound-guided behaviour, I used two-photon calcium imaging to measure the activity of neurons in the IC that receive projections from the AC while manipulating the AC inputs during a sound detection task. I found that individual cortico-recipient inferior colliculus (CRIC) neurons exhibited heterogeneous patterns of activity, and that the AC appears to be involved in influencing some of these patterns. Further, I showed that the CRIC trial-by-trial network activity contained behaviourally-relevant information, and that this information was more unreliable when the AC input was removed. Overall, this work offers novel insights into the neural and behavioural function of the auditory cortico-collicular pathway, which contributes to our understanding of the role of descending sensory pathways in perception and behaviour
Characteristics of virtual unipolar electrograms for detecting isthmus block during radiofrequency ablation of typical atrial flutter
AbstractObjectivesThe purpose of this study was to investigate the characteristics of the second component of local virtual unipolar electrograms recorded at the ablation line during coronary sinus (CS) pacing after radiofrequency ablation (RFA) of the cavotricuspid isthmus (CTI) for typical atrial flutter (AFL).BackgroundRadiofrequency ablation of the CTI can produce local double potentials at the ablation line. The second component of unipolar electrograms represents the approaching wavefront in the right atrium opposite the pacing site. We hypothesized that the morphologic characteristics of the second component of double potentials would be useful in detecting complete CTI block.MethodsRadiofrequency ablation of the CTI was performed in 52 patients (males = 37, females = 15, 62 ± 12 years) with typical AFL. The noncontact mapping system (Ensite 3000, Endocardial Solutions, St. Paul, Minnesota) was used to guide RFA. Virtual unipolar electrograms along the ablation line during CS pacing after RFA were analyzed. Complete or incomplete CTI block was confirmed by the activation sequence on the halo catheter and noncontact mapping.ResultsThree groups were classified after ablation. Group I (n = 37) had complete bidirectional CTI block. During CS pacing, the second component of unipolar electrograms showed an R or Rs pattern. Group II (n = 12) had incomplete CTI block. The second component of unipolar electrograms showed an rS pattern. Group III (n = 3) had complete CTI block with transcristal conduction. The second component of unipolar electrograms showed an rSR pattern.ConclusionsA predominant R-wave pattern in the second component of unipolar double potentials at the ablation line indicates complete CTI block, even in the presence of transcristal conduction
Learning Styles of Undergraduate and Graduate Physical Therapy Students in Taiwan
AbstractThe research was conducted to identify the learning styles of undergraduate and graduate physical therapy students in Taiwan and to examine the associations between learning style and academic performance. Basic data and Kolb's Learning Style Inventory were obtained from 52 participants from one university. The most commonly occurring style of learner was assimilator (44%), followed by diverger (23%), accommodator (15%), and converger (17%). There was no significant difference in academic performance among the four different styles of learners. Qualitative analyses provided further understanding of the preferred learning and teaching strategies. The different strategies are recommended to meet studentsâ learning preferences
Cortico-cortical feedback engages active dendrites in visual cortex
Sensory processing in the neocortex requires both feedforward and feedback information flow between cortical areas 1. In feedback processing, higher-level representations provide contextual information to lower levels, and facilitate perceptual functions such as contour integration and figureâground segmentation 2,3. However, we have limited understanding of the circuit and cellular mechanisms that mediate feedback influence. Here we use long-range all-optical connectivity mapping in mice to show that feedback influence from the lateromedial higher visual area (LM) to the primary visual cortex (V1) is spatially organized. When the source and target of feedback represent the same area of visual space, feedback is relatively suppressive. By contrast, when the source is offset from the target in visual space, feedback is relatively facilitating. Two-photon calcium imaging data show that this facilitating feedback is nonlinearly integrated in the apical tuft dendrites of V1 pyramidal neurons: retinotopically offset (surround) visual stimuli drive local dendritic calcium signals indicative of regenerative events, and two-photon optogenetic activation of LM neurons projecting to identified feedback-recipient spines in V1 can drive similar branch-specific local calcium signals. Our results show how neocortical feedback connectivity and nonlinear dendritic integration can together form a substrate to support both predictive and cooperative contextual interactions
Seizure After Local Anesthesia for Nasopharyngeal Angiofibroma
We report a young male patient who experienced seizure after local injection of 3 mL 2% lidocaine with epinephrine 1:200,000 around a recurrent nasal angiofibroma. After receiving 100% oxygen via mask and thiamylal sodium, the patient had no residual neurologic sequelae. Seizure immediately following the injection of local anesthetics in the nasal cavity is probably due to injection into venous or arterial circulation with retrograde flow to the brain circulation. Further imaging study or angiography should be done before head and neck surgeries, especially in such highly vascular neoplasm
Using the computer-based feedback (CBF) system to investigate the juniorphysiciansâs and clinical-instructors perceptions for the benefits of general medicine clinical-instructors training program
Background: The purpose of this study is to examine the clinical-instructors and junior-physicians (residents and interns) perceptions for the general-medicine training program by using bi-directional interactive and self-assessments computer-based feedback (CBF) and paper-based multisource feedback assessment (PBMFA) systems for the efficiency and benefit evaluation.Methods: Between 2011 January to 2013 December, junior-physicians and their clinical-instructors in the same medical team were enrolled consecutively for monitoring the CBF scores gave by each other after each clinical course. A total of 321 residents, 298 interns and 110 clinical-instructors who participated in the core competency general-medicine training program in 6-months period were included in the study. The CBF and PBMFA evaluations are undergone paralleled to gather the suggested information in different levels of Kirkpatrick evolutional theory.Results: The results showed that lecturers, being 5-10 years as attending physicians, internal medicine sub-specialty clinical-instructors are most benefit from the general medicine training program. Accordingly, the CBF scores of junior-physicians was positively correlated with the times (> 3-times) of exposure to the medical teams that leaded by qualified clinical-instructors. Both clinical-instructors and junior-physicians have positive attitude to the value of the general-medicine training program. Interestingly, a good consistency was existed between residents CBF scores and PBMFA grades for their core-competency performance. Comparatively, the overall perception of clinical-instructors and junior-physicians for the general-medicine training was very positive.Conclusions: Clinical-instructors and junior-physicians had positive perception of CBF and PBMFA systems which could give us different information to improve and strength the further core-competency general-medicine training program by appropriate utilization
Bevacizumab Dose Affects the Severity of Adverse Events in Gynecologic Malignancies
In this retrospective study, we investigated adverse events and outcomes in patients treated with bevacizumab for ovarian, fallopian tube, or primary peritoneal cancers at a single hospital. We determined the cumulative incidences of various bevacizumab-related adverse events and the correlation between dose and adverse event incidences. We analyzed data from 154 patients that received 251 rounds of bevacizumab as first-line, first salvage, >2 salvage treatments. Adverse events of any grade were observed in 121 (78.6%) patients; at least one grade 3 or 4 adverse event occurred in 32 (20.8%) patients. The two most common events were proteinuria (38.3%) and hypertension (33.8%). The first-line treatment group displayed significantly higher frequencies of hypertension (52.7% vs. 18.9% vs. 15.5%, p < 0.001), wound complications (9.1% vs. 0% vs. 1.2%, p = 0.010), arthralgia (29.1% vs. 11.3% vs. 8.3%, p = 0.003), and reduced range of joint motion (14.5% vs. 5.7% vs. 3.6%, p = 0.046), compared to those in the first and >2 lines salvage groups, respectively (KruskalâWallis test). The cumulative incidences of all grades and grades 3/4 of hypertension cumulative incidence plateaued at around 30% for all grades and 10% for grades 3 and 4, at bevacizumab doses above 8080 and 3510 mg, respectively. The proteinuria cumulative incidence plateaued at around 35% for all grades and 3% for grades 3 and 4, at bevacizumab doses above 11,190 and 4530 mg, respectively. We concluded that, in this realistic clinical population, different kinds and higher cumulative incidences of adverse events were observed compared to those reported in previous clinical trials. Moreover, bevacizumab doses showed cumulative toxicity and plateau effects on hypertension and proteinuria
Towards inclusive funding practices for early career researchers
Securing research funding is a challenge faced by most scientists in academic institutions worldwide. Funding success rates for all career stages are low, but the burden falls most heavily on early career researchers (ECRs). These are young investigators in training and new principal investigators who have a shorter track record. ECRs are dependent on funding to establish their academic careers. The low number of career development awards and the lack of sustained research funding result in the loss of ECR talent in academia. Several steps in the current funding process, from grant conditions to review, play significant roles in the distribution of funds. Furthermore, there is an imbalance where certain research disciplines and labs of influential researchers receive more funding. As a group of ECRs with global representation, we examined funding practices, barriers, and facilitators to the current funding systems. We also identified alternatives to the most common funding distribution practices, such as diversifying risk or awarding grants on a partly random basis. Here, we detail recommendations for funding agencies and grant reviewers to improve ECR funding prospects worldwide and promote a fairer and more inclusive funding landscape for ECRs.Instituto de VirologĂaFil: de Winde, Charlotte M. University College London. MRC Laboratory for Molecular Cell Biology; Reino UnidoFil: de Winde, Charlotte M. Amsterdam University Medical Center. Department of Molecular Cell Biology & Immunology; PaĂses BajosFil: Sarabipour, Sarvenaz. Johns Hopkins University. Department of Biomedical Engineering. Institute for Computational Medicine; Estados UnidosFil: Carignano, Hugo Adrian. Instituto Nacional de TecnologĂa Agropecuaria (INTA). Instituto de VirologĂa e Innovaciones TecnolĂłgicas; ArgentinaFil: Davla, Sejal. City University of New York. Advanced Science Research Center; Estados UnidosFil: Eccles, David. Malaghan Institute of Medical Research; Nueva ZelandaFil: Hainer, Sarah J. University of Pittsburgh. Department of Biological Sciences; Estados UnidosFil: Haidar, Mansour. Hasselt University; BĂ©lgicaFil: Ilangovan, Vinodh. Aarhus University; DinamarcaFil: Jadavji, Nafisa M. Midwestern University. Department of Biomedical Sciences; Estados UnidosFil: Jadavji, Nafisa M. Carleton University. Department of Neuroscience; CanadĂĄFil: Kritsiligkou, Paraskevi. German Cancer Research Center; AlemaniaFil: Lee, Tai-Ying. University of Oxford; Reino UnidoFil: ĂlafsdĂłttir, H. Freyja. Radboud University. Donders Institute for Brain, Cognition and Behaviour; PaĂses Bajo
The Radiological Manifestations of the Aberrant Air Surrounding the Pleura: In the Embryological View
The radiological manifestations of the aberrant air surrounding the pleura are varied because of the air outlining the organs in and out of the visceral space. The continuity of the visceral space from the neck, mediastinum to the retroperitoneum is originated from embryological development, which is compatible with the findings through laboratory experiments, cadaveric anatomy, and thoracic computer tomography image. We reviewed the embryo development to understand the anatomy of body cavity, which can determine the radiological findings of pneumomediastinum and pneumothorax
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