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dbMDEGA: a database for meta-analysis of differentially expressed genes in autism spectrum disorder.BMC Bioinformatics Nov 2017Autism spectrum disorders (ASD) are hereditary, heterogeneous and biologically complex neurodevelopmental disorders. Individual studies on gene expression in ASD cannot... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Autism spectrum disorders (ASD) are hereditary, heterogeneous and biologically complex neurodevelopmental disorders. Individual studies on gene expression in ASD cannot provide clear consensus conclusions. Therefore, a systematic review to synthesize the current findings from brain tissues and a search tool to share the meta-analysis results are urgently needed.
METHODS
Here, we conducted a meta-analysis of brain gene expression profiles in the current reported human ASD expression datasets (with 84 frozen male cortex samples, 17 female cortex samples, 32 cerebellum samples and 4 formalin fixed samples) and knock-out mouse ASD model expression datasets (with 80 collective brain samples). Then, we applied R language software and developed an interactive shared and updated database (dbMDEGA) displaying the results of meta-analysis of data from ASD studies regarding differentially expressed genes (DEGs) in the brain.
RESULTS
This database, dbMDEGA ( https://dbmdega.shinyapps.io/dbMDEGA/ ), is a publicly available web-portal for manual annotation and visualization of DEGs in the brain from data from ASD studies. This database uniquely presents meta-analysis values and homologous forest plots of DEGs in brain tissues. Gene entries are annotated with meta-values, statistical values and forest plots of DEGs in brain samples. This database aims to provide searchable meta-analysis results based on the current reported brain gene expression datasets of ASD to help detect candidate genes underlying this disorder.
CONCLUSION
This new analytical tool may provide valuable assistance in the discovery of DEGs and the elucidation of the molecular pathogenicity of ASD. This database model may be replicated to study other disorders.
Topics: Animals; Autism Spectrum Disorder; Cerebellum; Cerebral Cortex; Databases, Genetic; Female; Humans; Male; Mice; Transcriptome
PubMed: 29145823
DOI: 10.1186/s12859-017-1915-2 -
BMC Neurology Feb 2022Intra-cranial schwannomas account for less than 8% of brain tumors, among which more than 80% arise from the vestibular nerve. Intra-cerebellar schwannomas are extremely...
BACKGROUND
Intra-cranial schwannomas account for less than 8% of brain tumors, among which more than 80% arise from the vestibular nerve. Intra-cerebellar schwannomas are extremely rare. Several cases have been previously reported but without remarkable degenerative changes on histology.
CASE PRESENTATION
A 61-year-old man presented with worsening disorientation, and an imaging study revealed a cystic lesion (6.5 cm in the largest diameter) in the left hemisphere of the cerebellum accompanied by a mural nodule (2.5 cm) located just inside the skull with enhancement and focal calcification, in addition to hydrocephalus. The lesion was more than 5 mm from the left acoustic nerve. The patient underwent gross total resection. Pathological examination revealed remarkable degenerative changes with various morphological features. Tumor cells were pleomorphic with rich cytoplasm containing numerous eosinophilic granules. Blood vessels and extracellular matrix showed remarkable hyalinization. Immunohistochemical staining revealed that the tumor cells were positive for S-100 protein and negative for Olig2. The tumor was diagnosed as a schwannoma with marked degenerative changes.
CONCLUSIONS
The present case is discussed with reference to a systematic review of previous reports of intra-cerebellar schwannoma. Intra-cerebellar schwannoma should be included in the differential diagnosis of cystic lesions with heterogeneous histopathological morphology in the cerebellum.
Topics: Brain Neoplasms; Calcinosis; Cerebellum; Diagnosis, Differential; Humans; Male; Middle Aged; Neurilemmoma
PubMed: 35209854
DOI: 10.1186/s12883-022-02596-3 -
Systematic Reviews Jun 2020Vestibular compensation is a homeostatic process that occurs in the central nervous system in response to peripheral vestibular dysfunction. Experimental studies in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Vestibular compensation is a homeostatic process that occurs in the central nervous system in response to peripheral vestibular dysfunction. Experimental studies in rodent models have suggested that unilateral peripheral vestibular lesions are correlated with an increase in the intrinsic excitability of central vestibular neurons. This process may be dependent on the intrinsic properties of the neurons themselves. We aimed to conduct a systematic review of the literature to survey the evidence for changes in intrinsic plasticity observed during the acute phase of vestibular compensation.
METHODS
We systematically reviewed the literature regarding the electrophysiological effect of experimentally induced unilateral vestibular deafferentation (UVD) on the intrinsic membrane properties of medial vestibular nucleus neurons in animal models. We developed tools to assess the methodological quality (precision, validity and bias) of studies that met pre-determined inclusion and exclusion criteria. We extracted numerical data and performed a meta-analysis of specific quantitative data pooled from these studies.
RESULTS
We identified 17 studies that satisfied the inclusion criteria. There is moderate quality evidence to suggest a statistically significant increase in the intrinsic excitability of medial vestibular nucleus neurons following unilateral vestibular deafferentation. Specifically, the spontaneous discharge rate increases by 4 spikes/s on average and the sensitivity to current stimuli increases.
CONCLUSION
Using this novel approach, we demonstrate that the methodology of systematic review and meta-analysis is a useful tool in the summation of data across experimental animal studies with similar aims.
Topics: Animals; Denervation; Neuronal Plasticity; Neurons; Vestibular Nuclei
PubMed: 32552855
DOI: 10.1186/s13643-020-01399-2 -
International Clinical... Jul 2024Cerebellar alterations, including both volumetric changes in the cerebellar vermis and dysfunctions of the corticocerebellar connections, have been documented in...
INTRODUCTION
Cerebellar alterations, including both volumetric changes in the cerebellar vermis and dysfunctions of the corticocerebellar connections, have been documented in psychotic disorders. Starting from the clinical observation of a bipolar patient with cerebellar hypoplasia, the purpose of this review is to summarize the data in the literature about the association between hypoplasia of the cerebellar vermis and psychotic disorders [schizophrenia (SCZ) and bipolar disorder (BD)].
METHODS
A bibliographic search on PubMed has been conducted, and 18 articles were finally included in the review: five used patients with BD, 12 patients with SCZ and one subject at psychotic risk.
RESULTS
For SCZ patients and subjects at psychotic risk, the results of most of the reviewed studies seem to suggest a gray matter volume reduction coupled with an increase in white matter volumes in the cerebellar vermis, compared to healthy controls. Instead, the results of the studies on BD patients are more heterogeneous with evidence showing a reduction, no difference or even an increase in cerebellar vermis volume compared to healthy controls.
CONCLUSIONS
From the results of the reviewed studies, a possible correlation emerged between cerebellar vermis hypoplasia and psychotic disorders, especially SCZ, ultimately supporting the hypothesis of psychotic disorders as neurodevelopmental disorders.
Topics: Adult; Female; Humans; Bipolar Disorder; Cerebellar Vermis; Cerebellum; Developmental Disabilities; Magnetic Resonance Imaging; Nervous System Malformations; Psychotic Disorders; Schizophrenia
PubMed: 38266159
DOI: 10.1097/YIC.0000000000000535 -
Revista Da Associacao Medica Brasileira... Mar 2020Symptomatic Chiari Type I Malformation (CM) is treated with posterior fossa decompression with or without duroplasty. We have noticed some cases with concomitant severe...
BACKGROUND
Symptomatic Chiari Type I Malformation (CM) is treated with posterior fossa decompression with or without duroplasty. We have noticed some cases with concomitant severe cerebellar ataxia due to cerebellar atrophy. The aim of this study is to review the literature of CM associated with severe cerebellar atrophy and discuss its potential physiopathology.
METHODS
A systematic literature review in the Pubmed Database was performed using the following key-terms: "cerebellar atrophy Chiari", and "cerebellar degeneration Chiari". Articles reporting the presence of cerebellar degeneration/atrophy associated with CM were included.
RESULTS
We found only six studies directly discussing the association of cerebellar atrophy with CM, with a total of seven cases. We added one case of our own practice for additional discussion. Only speculative causes were described to justify cerebellar atrophy. The potential causes of cerebellar atrophy were diffuse cerebellar ischemia from chronic compression of small vessels (the most mentioned speculative cause), chronic raised intracranial pressure due to CSF block, chronic venous hypertension, and association with platybasia with ventral compression of the brainstem resulting in injury of the inferior olivary nuclei leading to mutual trophic effects in the cerebellum. Additionally, it is not impossible to rule out a degenerative cause for cerebellar atrophy without a causative reason.
CONCLUSIONS
Severe cerebellar atrophy is found in some patients with CM. Although chronic ischemia due to compression is the most presumed cause, other etiologies were proposed. The real reasons for cerebellar degeneration are not known. Further studies are necessary.
Topics: Arnold-Chiari Malformation; Atrophy; Cerebellar Diseases; Cerebellum; Decompression, Surgical; Female; Humans; Magnetic Resonance Imaging; Male
PubMed: 32520161
DOI: 10.1590/1806-9282.66.3.375 -
Journal of Clinical Neuroscience :... Aug 2019We studied patients with chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma and...
Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma: Comparison of clinical features and risk factors suggestive of underlying lymphomas.
BACKGROUND
We studied patients with chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) associated with or without lymphoma and measured risk factors suggestive of an underlying lymphoma and follow-up outcomes.
METHODS
CLIPPERS patients associated with or without lymphoma were included into this study. Clinical presentations were documented, risk factors suggestive of an underlying lymphoma were tested, and prognostic differences in terms of death were compared.
RESULTS
Ten patients had a diagnosis of CLIPPERS associated with lymphoma, with 6 B-cell non-Hodgkin lymphoma, 2 T-cell non-Hodgkin lymphoma and 2 Hodgkin lymphoma. Using multivariate logistic analysis, the following 3 independent risk factors were found to be related to a final diagnosis of lymphoma: hyperreflexia (HR 16.56; 95% CI 1.03-265.29; p = 0.032), elevated protein in CSF (HR 11.59; 95% CI 1.24-108.39; p = 0.047), and recurrences between 2 months and 1 year after treatment (HR 29.27; 95% CI 2.09-409.58; p = 0.012). The model calibration was satisfactory (p = 0.392 with the Hosmer-Lemeshow test), and the discrimination power was good (area under the receiver operating characteristic curve 0.921; p < 0.001, 95% CI 0.826-1.000). Patients with CLIPPERS associated with lymphoma had higher mortality rate and lymphoma was a significant predictor of total mortality (HR 0.040; 95% CI 0.006-0.262; p = 0.001).
CONCLUSIONS
Hyperreflexia, elevated protein in CSF and recurrences between 2 months and 1 year after treatment are risk factors suggesting an underlying lymphoma. Relapses during high-dose steroids maintenance therapy can be indicative of lymphoma, too. Patients having CLIPPERS associated with lymphoma have a worse prognosis than those without lymphoma.
Topics: Adult; Brain Diseases; Female; Humans; Inflammation; Lymphoma; Magnetic Resonance Imaging; Male; Middle Aged; Pons; Steroids
PubMed: 31088767
DOI: 10.1016/j.jocn.2019.04.022