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Creutzfeldt-Jakob disease in a man surviving COVID-19. Disentangling a casual or causal association by neuropathology
No full textAbstract
Background Literature reporting the onset of Creutzfeldt-Jakob disease (CJD) immediately after COVID-19 infection has
strengthened a possible causal link between infection and neurodegeneration. Here, we report a novel case undergoing
detailed neuropathological assessment.
Case report Two months after he had contracted SARS-CoV-2 infection, a 54-year-old man manifested a subacute onset of ataxia, headache, anosmia, and hallucinations, followed by rapidly progressive cognitive decline.
Electroencephalography documented unspecific slowing with periodic polyphasic delta waves. Brain MRI showed
hyperintensities of basal ganglia and thalami on DWI/FLAIR. CSF tested positive for the 14-3-3 protein, and prion
seeding activity was demonstrated by the real-time quaking-induced conversion assay. The patient died 2 months
after the neurologic onset. The neuropathological examination confirmed the diagnosis of CJD and ruled out COVID19-related encephalitis.
Discussion To disentangle the link between COVID-19 infection and CJD, neuropathology is essential determining the
extent of changes related to both conditions. In our patient, we did not fnd any specifc abnormality related to COVID-19.
Our conclusion is in line with the current worldwide epidemiological data that do not show an increase in CJD cases since
the beginning of the COVID-19 pandemi
Creutzfeldt–Jakob Disease Associated with E200K Mutation and SARS-CoV-2 Infection: Pure Coincidence or Neurodegenerative Acceleration?
No full textSeveral recent studies reported on some patients developing Creutzfeldt–Jakob disease (CJD) following coronavirus disease 2019, but, to the best of our knowledge, this case is the first reported in Italy on an onset of a CJD genetic form (gCJD) immediately after COVID-19 infection. We present a 51-year-old woman with a positive family history for CJD, who, two months after a mild SARS-CoV-2 infection, presented a rapidly progressing dementia diagnosed as CJD through clinical features, imaging, electroencephalography, and cerebrospinal fluid analysis. Genetic testing revealed the E200K mutation (p.Glu200Lys) c.598G>A, with homozygosity for methionine (MET) at codon 129, thus confirming the diagnosis of Creutzfeldt–Jakob disease. She passed away two months later. Interestingly, our case confirms that homozygous E200K gCJD patients are characterized by a relatively younger age of onset; moreover, it also sheds light on the neurodegeneration underlying both prion diseases and COVID-19 infection. In our opinion, the rising global prevalence of neurodegenerative complications following COVID-19 disease adds urgency to the study of this potential relationship, mostly in elderly patients who may experience worse long-lasting outcomes systemically and within the nervous system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Creutzfeldt-Jakob disease masked by head trauma and features of Wilson's disease
No full textCreutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disorder typically characterized by progressive dementia associated with myoclonus, cerebellar and other focal neurological signs. Electroencephalogram, brain MRI and cerebrospinal fluid (CSF) analyses are helpful diagnostic tools, but diagnosis in patients with atypical presenting neurological signs is often difficult to make. A 55-year-old woman developed disorientation, drowsiness and focal motor signs after a traumatic brain injury due to an accidental fall. In two weeks, her symptoms worsened in spite of a brain MRI showed an improvement of traumatic lesions, but the presence of bilateral hyperintensity in the basal nuclei was suggestive of a metabolic or prion encephalopathy. The high 24-h urinary copper level and reduction of ceruloplasmin initially supported the diagnosis of Wilson's disease, but the absence of Kayser-Fleischer rings, and the positivity of 14-3-3 protein test and elevated tau concentrations in the CSF oriented toward a diagnosis of CJD. She died 5 months after the onset, and the postmortem examination of the brain revealed immunochemical features of CJD. This case exemplifies the difficulty of a timely diagnosis when rapid progressive dementia is masked by concomitant factors (i.e., head trauma) and neurological signs are associated with unclear laboratory findings
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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