A primitive neoplasm composed predominantly of nonhost cells was detected in the thoracic spinal cord and thecal sac of a 66-year-old man who had received experimental stem-cell treatment from ...commercial clinics.
To the Editor:
Commercial stem-cell clinics have been highly publicized in the lay press and operate worldwide with limited or no regulation.
1
We report the case of a 66-year-old man who underwent intrathecal infusions for the treatment of residual deficits from an ischemic stroke at commercial stem-cell clinics in China, Argentina, and Mexico. He was not taking any immunosuppressive medications. In reports provided to him by the clinics, the infusions were described as consisting of mesenchymal, embryonic, and fetal neural stem cells. Progressive lower back pain, paraplegia, and urinary incontinence subsequently developed. Magnetic resonance imaging (MRI) revealed a lesion of . . .
Musical training has been associated with structural changes in the brain as well as functional differences in brain activity when musicians are compared to nonmusicians on both perceptual and motor ...tasks. Previous neuroimaging comparisons of musicians and nonmusicians in the motor domain have used tasks involving prelearned motor sequences or synchronization with an auditorily presented sequence during the experiment. Here we use functional magnetic resonance imaging (fMRI) to examine expertise-related differences in brain activity between musicians and nonmusicians during improvisation – the generation of novel musical–motor sequences – using a paradigm that we previously used in musicians alone. Despite behaviorally matched performance, the two groups showed significant differences in functional brain activity during improvisation. Specifically, musicians deactivated the right temporoparietal junction (rTPJ) during melodic improvisation, while nonmusicians showed no change in activity in this region. The rTPJ is thought to be part of a ventral attentional network for bottom-up stimulus-driven processing, and it has been postulated that deactivation of this region occurs in order to inhibit attentional shifts toward task-irrelevant stimuli during top-down, goal-driven behavior. We propose that the musicians' deactivation of the rTPJ during melodic improvisation may represent a training-induced shift toward inhibition of stimulus-driven attention, allowing for a more goal-directed performance state that aids in creative thought.
While some motor behavior is instinctive and stereotyped or learned and re-executed, much action is a spontaneous response to a novel set of environmental conditions. The neural correlates of both ...pre-learned and cued motor sequences have been previously studied, but novel motor behavior has thus far not been examined through brain imaging. In this paper, we report a study of musical improvisation in trained pianists with functional magnetic resonance imaging (fMRI), using improvisation as a case study of novel action generation. We demonstrate that both rhythmic (temporal) and melodic (ordinal) motor sequence creation modulate activity in a network of brain regions comprised of the dorsal premotor cortex, the rostral cingulate zone of the anterior cingulate cortex, and the inferior frontal gyrus. These findings are consistent with a role for the dorsal premotor cortex in movement coordination, the rostral cingulate zone in voluntary selection, and the inferior frontal gyrus in sequence generation. Thus, the invention of novel motor sequences in musical improvisation recruits a network of brain regions coordinated to generate possible sequences, select among them, and execute the decided-upon sequence.
Delirium is a common and costly complication of hospitalization. Although medications are a known cause of delirium, antibiotics are an underrecognized class of medications associated with delirium. ...In this article, we comprehensively review the clinical, radiologic, and electrophysiologic features of antibiotic-associated encephalopathy (AAE). AAE can be divided into 3 unique clinical phenotypesencephalopathy commonly accompanied by seizures or myoclonus arising within days after antibiotic administration (caused by cephalosporins and penicillin); encephalopathy characterized by psychosis arising within days of antibiotic administration (caused by quinolones, macrolides, and procaine penicillin); and encephalopathy accompanied by cerebellar signs and MRI abnormalities emerging weeks after initiation of antibiotics (caused by metronidazole). We correlate these 3 clinical phenotypes with underlying pathophysiologic mechanisms of antibiotic neurotoxicity. Familiarity with these types of antibiotic toxicity can improve timely diagnosis of AAE and prompt antibiotic discontinuation, reducing the time patients spend in the delirious state.
...many practitioners in settings without access to CT do not administer aspirin to any patients with acute stroke of unknown etiology due to concern that acute intracerebral haemorrhage, if present, ...could worsen.
Global health electives in neurology residencies provide opportunities for high-income country trainees, but have limited benefits–and may create burdens–for lower-income country hosts. Current ...suspension of global health electives for U.S. neurology residents due to the COVID-19 pandemic provides an opportunity to reflect on ways to reimagine global health education during this period and beyond. The framework proposed in this article underscores the need for equitable, bidirectional international partnerships and highlights global health educational innovations developed during the pandemic.
A Clinical Approach to Diagnosing Encephalopathy Erkkinen, Michael G.; Berkowitz, Aaron L.
The American journal of medicine,
October 2019, 2019-10-00, 20191001, Letnik:
132, Številka:
10
Journal Article
Recenzirano
Encephalopathy refers to dysfunction of the level or contents of consciousness due to brain dysfunction and can result from global brain insults or focal lesions. The underlying causes of ...encephalopathy include both primary neurologic and systemic conditions. This article discusses the differential diagnosis of encephalopathy, with a focus on primary neurologic causes. A practical schema for organizing the differential diagnosis is to group etiologies by their pace of onset and evolution (eg, sudden, acute, subacute, chronic).
Neurologic symptoms have been reported in over 30% of hospitalized patients with coronavirus disease 2019 (COVID-19), but the pathogenesis of these symptoms remains under investigation. Here, we ...place the neurologic complications of COVID-19 within the context of three historical viral pandemics that have been associated with neurologic diseases: (1) the 1918 influenza pandemic, subsequent spread of encephalitis lethargica, and lessons for the study of COVID-19-related neuroinflammation; (2) the controversial link between the 1976 influenza vaccination campaign and Guillain-Barré Syndrome and its implications for the post- and parainfectious complications of COVID-19 and COVID-19 vaccination; and (3) potential applications of scientific techniques developed in the wake of the human immunodeficiency virus pandemic to the study of postacute sequelae of COVID-19.
This paper describes the development, content, structure, and implementation of a case-based collaborative learning, flipped classroom, integrated preclinical neurology, neuroanatomy, and ...neuroscience course for first year medical students at Harvard Medical School. We report the methods for pre-class preparation, in-class instruction, and evaluation; student feedback with respect to content, teaching method, and learning environment; and several lessons learned regarding how to optimize preparatory and in-class learning in a case-based flipped classroom course.
•Active learning models include problem-based learning and team-based learning.•In the flipped classroom approach, students study material prior to class, and classroom time is used to apply what they have learned.•We describe a case-based, team-based, flipped classroom course integrating neuroanatomy/neuroscience and clinical neurology.
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