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Acta Otorrinolaringologica Espanola 2020There is debate as to whether olfactory dysfunction should be considered a symptom of COVID-19 infection, given the implications for managing the symptom itself, for...
There is debate as to whether olfactory dysfunction should be considered a symptom of COVID-19 infection, given the implications for managing the symptom itself, for diagnostic testing, and for implementing isolation measures. We undertook a systematic literature review of the articles indexed in PubMed on olfactory disorders in viral respiratory tract conditions, with special emphasis on COVID-19. The main objective was to find evidence of clinical interest to support the relationship between anosmia and COVID-19. Olfactory disorders in upper respiratory tract infections are frequent, most caused by obstruction due to oedema of the nasal mucosa. Occasionally, post-viral sensorineural olfactory dysfunction occurs, with a variable prognosis. The evidence on anosmia in COVID-19 patients is extremely limited, corresponding to a level 5 or D of the Centre for Evidence-Based Medicine. According to the various medical societies that have issued reports on the subject, it seems reasonable to apply isolation, hygiene and social distancing measures in patients with recent olfactory disorders as the only symptom, although the usefulness of diagnostic tests for this type of patient should be studied.
Topics: Betacoronavirus; COVID-19; COVID-19 Testing; Clinical Laboratory Techniques; Coronavirus Infections; Humans; Hygiene; Olfaction Disorders; Olfactory Mucosa; Pandemics; Patient Isolation; Pneumonia, Viral; Practice Guidelines as Topic; Prognosis; Quarantine; Respiratory Tract Infections; SARS-CoV-2; Virus Diseases
PubMed: 32466862
DOI: 10.1016/j.otorri.2020.04.003 -
PLoS Biology May 2016Olfactory ensheathing cell (OEC) transplantation is a candidate cellular treatment approach for human spinal cord injury (SCI) due to their unique regenerative potential... (Meta-Analysis)
Meta-Analysis
Olfactory Ensheathing Cell Transplantation in Experimental Spinal Cord Injury: Effect size and Reporting Bias of 62 Experimental Treatments: A Systematic Review and Meta-Analysis.
Olfactory ensheathing cell (OEC) transplantation is a candidate cellular treatment approach for human spinal cord injury (SCI) due to their unique regenerative potential and autologous origin. The objective of this study was, through a meta-epidemiologic approach, (i) to assess the efficacy of OEC transplantation on locomotor recovery after traumatic experimental SCI and (ii) to estimate the likelihood of reporting bias and/or missing data. A study protocol was finalized before data collection. Embedded into a systematic review and meta-analysis, we conducted a literature research of databases including PubMed, EMBASE, and ISI Web of Science from 1949/01 to 2014/10 with no language restrictions, screened by two independent investigators. Studies were included if they assessed neurobehavioral improvement after traumatic experimental SCI, administrated no combined interventions, and reported the number of animals in the treatment and control group. Individual effect sizes were pooled using a random effects model. Details regarding the study design were extracted and impact of these on locomotor outcome was assessed by meta-regression. Missing data (reporting bias) was determined by Egger regression and Funnel-plotting. The primary study outcome assessed was improvement in locomotor function at the final time point of measurement. We included 49 studies (62 experiments, 1,164 animals) in the final analysis. The overall improvement in locomotor function after OEC transplantation, measured using the Basso, Beattie, and Bresnahan (BBB) score, was 20.3% (95% CI 17.8-29.5). One missing study was imputed by trim and fill analysis, suggesting only slight publication bias and reducing the overall effect to a 19.2% improvement of locomotor activity. Dose-response ratio supports neurobiological plausibility. Studies were assessed using a 9-point item quality score, resulting in a median score of 5 (interquartile range [IQR] 3-5). In conclusion, OEC transplantation exerts considerable beneficial effects on neurobehavioral recovery after traumatic experimental SCI. Publication bias was minimal and affirms the translational potential of efficacy, but safety cannot be adequately assessed. The data justify OECs as a cellular substrate to develop and optimize minimally invasive and safe cellular transplantation paradigms for the lesioned spinal cord embedded into state-of-the-art Phase I/II clinical trial design studies for human SCI.
Topics: Animals; Cell Transplantation; Disease Models, Animal; Olfactory Bulb; Publication Bias; Spinal Cord Injuries; Treatment Outcome
PubMed: 27244556
DOI: 10.1371/journal.pbio.1002468 -
Regenerative Therapy Dec 2024Spinal cord injury is a lesion with high mortality and significant morbidities. After the primary injury, during six months, a cascade of secondary cellular and... (Review)
Review
Spinal cord injury is a lesion with high mortality and significant morbidities. After the primary injury, during six months, a cascade of secondary cellular and molecular events makes the lesion chronic. Recently, cell-based clinical trials as a new procedure have been gradually tested to improve the symptoms of patients. Each treatment method is associated with different adverse events. Based on the PRISMA flow diagram of the identified records, and after multistep screening, finally in 76 reviewed studies with 1633 cases and 189 controls, 64 types of adverse events in 12 categories were recorded in 45 studies. The most common adverse events were transient backache and meningism (90%) and cord malacia (80%). The cell therapy method in which the treatment was associated with more adverse events was Olfactory ensheathing cell and bone marrow mesenchymal stem cell combination therapy in 55%, and the adverse events were less with the embryonic stem cell in 2.33% of patients. In a meta-analysis, the total prevalence of adverse events in cell therapy was 19% and the highest pulled effect size belonged to urinary tract and localized adverse events. Also, the total prevalence of adverse events in 14 cell therapy methods was 18% and four cell types (neural stem cell, bone marrow hematopoietic stem cell, embryonic stem cell, and umbilical cord mesenchymal stem cell) had the most effect. None of the adverse events were reported on the 4 (life-threatening consequences) and 5 (death) grading scales. We concluded that the frequency of life-threatening adverse events following cell therapy clinical trials in chronic spinal cord injury patients is very scarce and can be ignored.
PubMed: 38694447
DOI: 10.1016/j.reth.2024.03.012 -
International Journal of Environmental... Sep 2020The Coronavirus Disease 2019 (COVID-19) outbreak has shocked the whole world with its unexpected rapid spread. The virus responsible for the disease, the Severe Acute...
The Coronavirus Disease 2019 (COVID-19) outbreak has shocked the whole world with its unexpected rapid spread. The virus responsible for the disease, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), enters host cells by means of the envelope spike protein, which binds to angiotensin-converting enzyme 2 receptors. These receptors are highly expressed in heart, lungs, respiratory tract epithelium, endothelial cells and brain. Since an increasing body of significant evidence is highlighting a possible neuroinvasion related to SARS-CoV-2, a state of the art on the neurological complications is needed. To identify suitable publications, our systematic review was carried out by searching relevant studies on PubMed and Scopus databases. We included studies investigating neurologic manifestations of SARS-CoV-2 in patients over 18. According to the analyzed studies, the most frequent disorders affecting central nervous system (CNS) seem to be the following: olfactory and taste disorders, ischemic/hemorrhagic stroke, meningoencephalitis and encephalopathy, including acute necrotizing encephalopathy, a rare type of encephalopathy. As regards the peripheral nervous system (PNS), Guillain-Barré and Miller Fisher syndromes are the most frequent manifestations reported in the literature. Important clinical information on the neurological manifestations of SARS-CoV-2 would help clinicians raise awareness and simultaneously improve the prognosis of critically ill patients.
Topics: Betacoronavirus; COVID-19; Central Nervous System Diseases; Coronavirus Infections; Guillain-Barre Syndrome; Humans; Miller Fisher Syndrome; Pandemics; Pneumonia, Viral; SARS-CoV-2
PubMed: 32937949
DOI: 10.3390/ijerph17186688 -
Clinical Neurology and Neurosurgery Jul 2020Increasing research reports neurological manifestations of COVID-19 patients. SARS-CoV-2 shares homology with other human coronaviruses that have also had nervous system...
BACKGROUND
Increasing research reports neurological manifestations of COVID-19 patients. SARS-CoV-2 shares homology with other human coronaviruses that have also had nervous system involvement.
OBJECTIVE
To review the neurological aspects of SARS-cov2 and other coronavirus, including transmission pathways, mechanisms of invasion into the nervous system, and mechanisms of neurological disease.
METHODS
We conducted a systematic review of articles in PubMed, SCOPUS and EMBASE data bases. Reviewed evidence is presented in sections of this manuscript which includes pathogenesis, neuro-invasion, encephalitis, Guillain-Barré, ADEM, multiple sclerosis, polyneuropathy, and cerebrovascular disease.
RESULTS
A total 67 studies were included in the final analysis of experimental studies, case reports, series of cases, cohort studies, and systematic reviews related to neurological manifestations of SARS- CoV-2 and other human coronavirus infections. The SARS-CoV-2 receptor is expressed in the nervous system. Common reported symptoms included hyposmia, headaches, weakness, altered consciousness. Encephalitis, demyelination, neuropathy, and stroke have been associated with COVID-19. Infection through the cribriform plate and olfactory bulb and dissemination through trans-synaptic transfer are some of the mechanisms proposed. Invasion of the medullary cardiorespiratory center by SARS-CoV-2 may contribute to the refractory respiratory failure observed in critically-ill COVID-19 patients.
CONCLUSION
An increasing number of reports of COVID-19 patients with neurological disorders add to emergent experimental models with neuro-invasion as a reasonable concern that SARS-CoV-2 is a new neuropathogen. How it may cause acute and chronic neurologic disorders needs to be clarified in future research.
Topics: Betacoronavirus; Brain; COVID-19; Coronavirus Infections; Humans; Nervous System Diseases; Observational Studies as Topic; Pandemics; Pneumonia, Viral; SARS-CoV-2
PubMed: 32422545
DOI: 10.1016/j.clineuro.2020.105921 -
Frontiers in Neurology 2020There is emerging evidence that Guillain-Barré syndrome (GBS) may be associated with coronavirus disease 2019 (COVID-19) infection. The aim of this review was to...
There is emerging evidence that Guillain-Barré syndrome (GBS) may be associated with coronavirus disease 2019 (COVID-19) infection. The aim of this review was to investigate the strength of the evidence. The review was registered in PROSPERO (CDR42020184822). Three electronic databases, MEDLINE, PubMed, and Web of Science, and three preprint servers, MedRvix, ChemRvix, and BioRvix, were searched from December 2019 to 24th September 2020. Studies were included if they were on COVID-19 and of any design. Articles that are reviews or opinion were excluded. The selection process was carried out using EndNote and Rayyan software. The main outcomes in the study were study design, sample size, sex, age, overall GBS symptoms, other COVID-19 symptoms, comorbidity, timing between infection and the onset of neurological symptoms, CT, MRI, and EMG results. Methodological quality of the studies was assessed using the McMaster Critical Review Form. The collected data was analyzed using qualitative synthesis. Fifty-one high-quality studies (mostly) consisting of 83 patients were included in the study. All of the patients (except in a very few) in the included studies had confirmed diagnosis of COVID-19. Similarly, the diagnosis of GBS was based on standard clinical, electrophysiological, and cerebrospinal fluid (CSF) criteria. GBS may be associated with COVID-19, and therefore, testing for COVID-19 is recommended in patients presenting with GBS during this pandemic.
PubMed: 33519663
DOI: 10.3389/fneur.2020.566308