Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 330
Filtrar
2.
Artigo em Inglês | MEDLINE | ID: mdl-39350506

RESUMO

Sex differences in patterns of cortical thickness and neuropsychiatric symptom (NPS) burden were examined among individuals with Alzheimer's disease (AD) and two copies (homozygote carriers) of the e4 allele of the apolipoprotein gene (APOE). A total of 752 participants with a clinical etiologic diagnosis of AD were selected from the National Alzheimer's Coordinating Center (NACC) database. Bayesian multilevel regression was used to examine both the within- and between-sex differences in gray-matter cortical thickness and total NPS burden associated with APOE homozygosity. Female homozygote carriers displayed a high probability of having reduced cortical thickness primarily in medial-lateral temporal regions and a greater burden of NPS, relative to both non-homozygous females and homozygous males. These findings support the notion that APOE4 status affects cortical thickness and symptom burden in men and women with AD differentially, with females showing more pronounced effects in brain areas known to be vulnerable in early AD. Future investigations should attempt to elucidate the proposed pattern of decline longitudinally.

3.
Eur Neuropsychopharmacol ; 89: 41-46, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39332148

RESUMO

This prospective observational study aimed to evaluate the rate of change in forced expiratory volume in the first second (FEV1) and to explore the factors associated with changes in FEV1 in people with serious mental illness (SMI). Sixty subjects diagnosed with schizophrenia or bipolar disorder who were smokers and without history of respiratory illness agreed to participate. The mean (range) follow-up period was 3.54 (3.00-4.98) years. The mean (standard deviation) annual rate of change in FEV1 decreased by 39.1 (105.2) mL/year. Thirty-one (51.7 %) patients experienced a decrease in the FEV1 ≥40 mL/year (i.e. a rapid decline). The factors associated with the absolute change in FEV1 were the baseline International Physical Activity Questionnaire activity score in metabolic equivalents of tasks (ß 0.145, 95 % confidence interval [CI] 0.043 to 0.246; p = 0.005), baseline FEV1 (ß -0.025, 95 % CI -0.076 to 0.027; p = 0.352), and the interaction term of both variables (ß -3.172e-05, 95 % CI -6.025e-05 to -0.319e-05; p = 0.029). The factors associated with rapid FEV1 decline were income (odds ratio [OR] 0.999, 95 % CI 0.995 to 1.003; p = 0.572), the rate of change in abdominal circumference (OR 0.000, 95 % CI 0.000 to 0.890; p = 0.081), and the interaction term of both variables (OR 1.038, 95 % CI 1.010 to 1.082; p = 0.026). In conclusion, a substantial proportion of people with SMI experienced a rapid decrease in FEV1. If our results are confirmed in larger samples, the routine evaluation of lung function in people with SMI would be an opportunity to identify individuals at greater risk of morbidity and mortality.

4.
Biol Lett ; 20(8): 20240033, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39140203

RESUMO

Characterizing the population density of species is a central interest in ecology. Eastern North America is the global hotspot for biodiversity of plethodontid salamanders, an inconspicuous component of terrestrial vertebrate communities, and among the most widespread is the eastern red-backed salamander, Plethodon cinereus. Previous work suggests population densities are high with significant geographic variation, but comparisons among locations are challenged by lack of standardization of methods and failure to accommodate imperfect detection. We present results from a large-scale research network that accounts for detection uncertainty using systematic survey protocols and robust statistical models. We analysed mark-recapture data from 18 study areas across much of the species range. Estimated salamander densities ranged from 1950 to 34 300 salamanders ha-1, with a median of 9965 salamanders ha-1. We compared these results to previous estimates for P. cinereus and other abundant terrestrial vertebrates. We demonstrate that overall the biomass of P. cinereus, a secondary consumer, is of similar or greater magnitude to widespread primary consumers such as white-tailed deer (Odocoileus virginianus) and Peromyscus mice, and two to three orders of magnitude greater than common secondary consumer species. Our results add empirical evidence that P. cinereus, and amphibians in general, are an outsized component of terrestrial vertebrate communities in temperate ecosystems.


Assuntos
Biomassa , Florestas , Densidade Demográfica , Urodelos , Animais , Urodelos/fisiologia , Biodiversidade , América do Norte
5.
Sensors (Basel) ; 24(15)2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39123938

RESUMO

High-intensity activities are related to success in football. We looked at whether high-intensity activity differed between home and away matches and its impact on the final score. Thirty football players (20.3 ± 0.8 years) were recruited from a Spanish semi-professional team. Footballers wore a GPS device to monitor high-intensity parameters from competition matches. The final score of every match was also recorded. Playing at home showed greater total distance (TD) > 24 km/h, >27 km/h, >85% Vmax, and the number of sprints > 24 km/h (all p < 0.05) than playing away. Positive correlations were also found between the match score and high-speed running (HSR) distance covered by the team per minute (r = 0.401), TD > 21 km/h (r = 0.417), TD > 24 km/h (r = 0.343), number of sprints > 24 km/h (r = 0.337), and HSR per minute (r = 0.459) (all p < 0.05). The results suggest that playing at home is associated with greater high-intensity effort than playing away. Moreover, the volume of high-intensity effort influences the final score.


Assuntos
Desempenho Atlético , Sistemas de Informação Geográfica , Corrida , Futebol , Humanos , Futebol/fisiologia , Corrida/fisiologia , Masculino , Desempenho Atlético/fisiologia , Adulto Jovem , Adulto
6.
Sensors (Basel) ; 24(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39123978

RESUMO

Monitoring a deep geological repository for radioactive waste during the operational phases relies on a combination of fit-for-purpose numerical simulations and online sensor measurements, both producing complementary massive data, which can then be compared to predict reliable and integrated information (e.g., in a digital twin) reflecting the actual physical evolution of the installation over the long term (i.e., a century), the ultimate objective being to assess that the repository components/processes are effectively following the expected trajectory towards the closure phase. Data prediction involves using historical data and statistical methods to forecast future outcomes, but it faces challenges such as data quality issues, the complexity of real-world data, and the difficulty in balancing model complexity. Feature selection, overfitting, and the interpretability of complex models further contribute to the complexity. Data reconciliation involves aligning model with in situ data, but a major challenge is to create models capturing all the complexity of the real world, encompassing dynamic variables, as well as the residual and complex near-field effects on measurements (e.g., sensors coupling). This difficulty can result in residual discrepancies between simulated and real data, highlighting the challenge of accurately estimating real-world intricacies within predictive models during the reconciliation process. The paper delves into these challenges for complex and instrumented systems (multi-scale, multi-physics, and multi-media), discussing practical applications of machine and deep learning methods in the case study of thermal loading monitoring of a high-level waste (HLW) cell demonstrator (called ALC1605) implemented at Andra's underground research laboratory.

7.
J Comp Neurol ; 532(8): e25662, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39136357

RESUMO

Despite myriad technological advances in neuroscience, the nervous system harbors morphological phenomena that continue to defy explanation. First described by the classical microscopists, including Santiago Ramon y Cajal, at the end of the 19th century, the neuronal intranuclear rodlet (INR) has mystified neurohistologists and microscopists for centuries. In this review article, we will provide an overview of the discovery of the INR as well as the subsequent attempts to elucidate its nature and functional significance. We outline our own studies of this structure over the past three decades, focusing on its elusive nature, its interactions with other nuclear organelles, and on disease-related quantitative changes in Alzheimer's disease. We then describe our somewhat serendipitous discovery that these structures are filamentous aggregates of the nucleotide-synthesizing metabolic enzyme inosine monophosphate dehydrogenase. The filamentation of metabolic enzymes to form mesoscale cellular structures called "rods and rings" or "cytoophidia" (Greek for "cellular snakes") is a recently described phenomenon that remains to be systematically investigated in the nervous system. Thus, this review provides an intriguing historical juxtaposition in neuroscience, inculcating the neuronal INR, once a mere morphological curiosity, into one of the most rapidly evolving fields in contemporary cell biology.


Assuntos
Neurônios , Humanos , Animais , Corpos de Inclusão Intranuclear/metabolismo , Doença de Alzheimer/história , Doença de Alzheimer/patologia , História do Século XX
8.
medRxiv ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38978643

RESUMO

Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) is a fatal neurodegenerative disorder with only a limited number of risk loci identified. We report our comprehensive genome-wide association study as part of the International FTLD-TDP Whole-Genome Sequencing Consortium, including 985 cases and 3,153 controls, and meta-analysis with the Dementia-seq cohort, compiled from 26 institutions/brain banks in the United States, Europe and Australia. We confirm UNC13A as the strongest overall FTLD-TDP risk factor and identify TNIP1 as a novel FTLD-TDP risk factor. In subgroup analyses, we further identify for the first time genome-wide significant loci specific to each of the three main FTLD-TDP pathological subtypes (A, B and C), as well as enrichment of risk loci in distinct tissues, brain regions, and neuronal subtypes, suggesting distinct disease aetiologies in each of the subtypes. Rare variant analysis confirmed TBK1 and identified VIPR1 , RBPJL , and L3MBTL1 as novel subtype specific FTLD-TDP risk genes, further highlighting the role of innate and adaptive immunity and notch signalling pathway in FTLD-TDP, with potential diagnostic and novel therapeutic implications.

9.
Cells Dev ; 179: 203924, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38692409

RESUMO

While understanding the genetic underpinnings of osteogenesis has far-reaching implications for skeletal diseases and evolution, a comprehensive characterization of the osteoblastic regulatory landscape in non-mammalian vertebrates is still lacking. Here, we compared the ATAC-Seq profile of Xenopus tropicalis (Xt) osteoblasts to a variety of non mineralizing control tissues, and identified osteoblast-specific nucleosome free regions (NFRs) at 527 promoters and 6747 distal regions. Sequence analyses, Gene Ontology, RNA-Seq and ChIP-Seq against four key histone marks confirmed that the distal regions correspond to bona fide osteogenic transcriptional enhancers exhibiting a shared regulatory logic with mammals. We report 425 regulatory regions conserved with human and globally associated to skeletogenic genes. Of these, 35 regions have been shown to impact human skeletal phenotypes by GWAS, including one trps1 enhancer and the runx2 promoter, two genes which are respectively involved in trichorhinophalangeal syndrome type I and cleidocranial dysplasia. Intriguingly, 60 osteoblastic NFRs also align to the genome of the elephant shark, a species lacking osteoblasts and bone tissue. To tackle this paradox, we chose to focus on dlx5 because its conserved promoter, known to integrate regulatory inputs during mammalian osteogenesis, harbours an osteoblast-specific NFR in both frog and human. Hence, we show that dlx5 is expressed in Xt and elephant shark odontoblasts, supporting a common cellular and genetic origin of bone and dentine. Taken together, our work (i) unravels the Xt osteogenic regulatory landscape, (ii) illustrates how cross-species comparisons harvest data relevant to human biology and (iii) reveals that a set of genes including bnc2, dlx5, ebf3, mir199a, nfia, runx2 and zfhx4 drove the development of a primitive form of mineralized skeletal tissue deep in the vertebrate lineage.


Assuntos
Cromatina , Elementos Facilitadores Genéticos , Osteoblastos , Fenótipo , Regiões Promotoras Genéticas , Xenopus , Animais , Humanos , Osteoblastos/metabolismo , Regiões Promotoras Genéticas/genética , Xenopus/genética , Elementos Facilitadores Genéticos/genética , Cromatina/metabolismo , Cromatina/genética , Evolução Biológica , Vertebrados/genética , Osso e Ossos/metabolismo , Osteogênese/genética
10.
AJNR Am J Neuroradiol ; 45(7): 850-854, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38724198

RESUMO

Epstein-Barr virus, a herpesvirus, has been associated with a variety of cancers, including Burkitt, Hodgkin, and non-Hodgkin lymphomas; posttransplant lymphoproliferative disorders; gastric carcinoma; and nasopharyngeal carcinoma, in both immunocompetent and immunocompromised individuals. Previous studies have established a connection between Epstein-Barr virus and the development of smooth-muscle tumors. Smooth-muscle tumors of the brain are very rare and are often misdiagnosed as meningiomas on imaging. To our knowledge, advanced imaging findings such as MR perfusion of smooth-muscle tumors of the brain have never been reported. We describe the radiologic and pathologic features of the Epstein-Barr virus-associated smooth-muscle tumors of the brain in a person with newly diagnosed advanced HIV.


Assuntos
Neoplasias Encefálicas , Infecções por Vírus Epstein-Barr , Tumor de Músculo Liso , Humanos , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico por imagem , Tumor de Músculo Liso/virologia , Tumor de Músculo Liso/diagnóstico por imagem , Tumor de Músculo Liso/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Masculino , Imageamento por Ressonância Magnética/métodos , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , Adulto
13.
Nat Commun ; 15(1): 4251, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762487

RESUMO

Sea level rise (SLR) affects coastal flood regimes and poses serious challenges to flood risk management, particularly on ungauged coasts. To address the challenge of monitoring SLR at local scales, we propose a high tide flood (HTF) thresholding system that leverages machine learning (ML) techniques to estimate SLR and HTF thresholds at a relatively fine spatial resolution (10 km) along the United States' coastlines. The proposed system, complementing conventional linear- and point-based estimations of HTF thresholds and SLR rates, can estimate these values at ungauged stretches of the coast. Trained and validated against National Oceanic and Atmospheric Administration (NOAA) gauge data, our system demonstrates promising skills with an average Kling-Gupta Efficiency (KGE) of 0.77. The results can raise community awareness about SLR impacts by documenting the chronic signal of HTF and providing useful information for adaptation planning. The findings encourage further application of ML in achieving spatially distributed thresholds.

14.
J Neurol ; 271(7): 4540-4550, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38717612

RESUMO

OBJECTIVES: To investigate whether a history of traumatic brain injury (TBI) is associated with greater long-term grey-matter loss in patients with mild cognitive impairment (MCI). METHODS: 85 patients with MCI were identified, including 26 with a previous history of traumatic brain injury (MCI[TBI-]) and 59 without (MCI[TBI+]). Cortical thickness was evaluated by segmenting T1-weighted MRI scans acquired longitudinally over a 2-year period. Bayesian multilevel modelling was used to evaluate group differences in baseline cortical thickness and longitudinal change, as well as group differences in neuropsychological measures of executive function. RESULTS: At baseline, the MCI[TBI+] group had less grey matter within right entorhinal, left medial orbitofrontal and inferior temporal cortex areas bilaterally. Longitudinally, the MCI[TBI+] group also exhibited greater longitudinal declines in left rostral middle frontal, the left caudal middle frontal and left lateral orbitofrontal areas sover the span of 2 years (median = 1-2%, 90%HDI [-0.01%: -0.001%], probability of direction (PD) = 90-99%). The MCI[TBI+] group also displayed greater longitudinal declines in Trail-Making-Test (TMT)-derived ratio (median: 0.737%, 90%HDI: [0.229%: 1.31%], PD = 98.8%) and differences scores (median: 20.6%, 90%HDI: [-5.17%: 43.2%], PD = 91.7%). CONCLUSIONS: Our findings support the notion that patients with MCI and a history of TBI are at risk of accelerated neurodegeneration, displaying greatest evidence for cortical atrophy within the left middle frontal and lateral orbitofrontal frontal cortex. Importantly, these results suggest that long-term TBI-mediated atrophy is more pronounced in areas vulnerable to TBI-related mechanical injury, highlighting their potential relevance for diagnostic forms of intervention in TBI.


Assuntos
Lesões Encefálicas Traumáticas , Disfunção Cognitiva , Substância Cinzenta , Imageamento por Ressonância Magnética , Humanos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/diagnóstico por imagem , Masculino , Feminino , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/complicações , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Idoso , Pessoa de Meia-Idade , Estudos Longitudinais , Testes Neuropsicológicos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Teorema de Bayes
15.
Neuroradiology ; 66(6): 947-953, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38625616

RESUMO

PURPOSE: Basal duct-like recess (DR) sign serves as a specific marker of papillary craniopharyngiomas (PCPs) of the strictly third-ventricular (3 V) topography. Origins of this sign are poorly understood with limited validation in external cohorts. METHODS: In this retrospective study, MRIs of pathologically proven PCPs were reviewed and evaluated for tumor topography, DR sign prevalence, and morphological subtypes. RESULTS: Twenty-three cases with 24 MRIs satisfied our inclusion criteria. Median age was 44.5 years with a predominant male distribution (M/F ratio 4.7:1). Overall, strictly 3 V was the commonest tumor topography (8/24, 33.3%), and tumors were most commonly solid-cystic (10/24, 41.7%). The prevalence of DR sign was 21.7% (5/23 cases), all with strictly 3 V topography and with a predominantly solid consistency. The sensitivity, specificity and positive and negative predictive value of the DR sign for strict 3 V topography was 62.5%, 100%, 100% and 84.2% respectively. New pertinent findings associated with the DR sign were observed in our cohort. This included development of the cleft-like variant of DR sign after a 9-year follow-up initially absent at baseline imaging. Additionally, cystic dilatation of the basal tumor cleft at the pituitary stalk-tumor junction and presence of a vascular structure overlapping the DR sign were noted. Relevant mechanisms, hypotheses, and implications were explored. CONCLUSION: We confirm the DR sign as a highly specific marker of the strictly 3 V topography in PCPs. While embryological and molecular factors remain pertinent in understanding origins of the DR sign, non-embryological mechanisms may play a role in development of the cleft-like variant.


Assuntos
Craniofaringioma , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias , Sensibilidade e Especificidade , Humanos , Masculino , Craniofaringioma/diagnóstico por imagem , Feminino , Neoplasias Hipofisárias/diagnóstico por imagem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Idoso , Prevalência , Adolescente , Terceiro Ventrículo/diagnóstico por imagem , Terceiro Ventrículo/patologia
16.
Int J Geriatr Psychiatry ; 39(3): e6074, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38491809

RESUMO

OBJECTIVES: Neuropsychiatric symptoms (NPS) increase risk of developing dementia and are linked to various neurodegenerative conditions, including mild cognitive impairment (MCI due to Alzheimer's disease [AD]), cerebrovascular disease (CVD), and Parkinson's disease (PD). We explored the structural neural correlates of NPS cross-sectionally and longitudinally across various neurodegenerative diagnoses. METHODS: The study included individuals with MCI due to AD, (n = 74), CVD (n = 143), and PD (n = 137) at baseline, and at 2-years follow-up (MCI due to AD, n = 37, CVD n = 103, and PD n = 84). We assessed the severity of NPS using the Neuropsychiatric Inventory Questionnaire. For brain structure we included cortical thickness and subcortical volume of predefined regions of interest associated with corticolimbic and frontal-executive circuits. RESULTS: Cross-sectional analysis revealed significant negative correlations between appetite with both circuits in the MCI and CVD groups, while apathy was associated with these circuits in both the MCI and PD groups. Longitudinally, changes in apathy scores in the MCI group were negatively linked to the changes of the frontal-executive circuit. In the CVD group, changes in agitation and nighttime behavior were negatively associated with the corticolimbic and frontal-executive circuits, respectively. In the PD group, changes in disinhibition and apathy were positively associated with the corticolimbic and frontal-executive circuits, respectively. CONCLUSIONS: The observed correlations suggest that underlying pathological changes in the brain may contribute to alterations in neural activity associated with MBI. Notably, the difference between cross-sectional and longitudinal results indicates the necessity of conducting longitudinal studies for reproducible findings and drawing robust inferences.


Assuntos
Doença de Alzheimer , Transtornos Cerebrovasculares , Disfunção Cognitiva , Doença de Parkinson , Humanos , Estudos Transversais , Doença de Parkinson/psicologia , Estudos Longitudinais , Disfunção Cognitiva/psicologia , Doença de Alzheimer/psicologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos Cerebrovasculares/complicações , Testes Neuropsicológicos
17.
Cogn Behav Neurol ; 37(1): 3-12, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38498721

RESUMO

We present a review of the definition, classification, and epidemiology of primary progressive aphasia (PPA); an update of the taxonomy of the clinical syndrome of PPA; and recent advances in the neuroanatomy, pathology, and genetics of PPA, as well as the search for biomarkers and treatment. PPA studies that have contributed to concepts of language organization and disease propagation in neurodegeneration are also reviewed. In addition, the issues of heterogeneity versus the relationships of the clinical phenotypes and their relationship to biological, pathological, and genetic advances are discussed, as is PPA's relationship to other conditions such as frontotemporal dementia, corticobasal degeneration, progressive supranuclear palsy, Pick disease, and amyotrophic lateral sclerosis. Arguments are presented in favor of considering these conditions as one entity versus many.


Assuntos
Afasia Primária Progressiva , Demência Frontotemporal , Paralisia Supranuclear Progressiva , Humanos , Demência Frontotemporal/diagnóstico , Demência Frontotemporal/genética , Paralisia Supranuclear Progressiva/genética , Paralisia Supranuclear Progressiva/patologia , Síndrome
18.
Neurooncol Adv ; 6(1): vdae001, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38312227

RESUMO

Background: Patients with glioblastoma (GBM) have a median overall survival (OS) of approximately 16 months. However, approximately 5% of patients survive >5 years. This study examines the differences in methylation profiles between long-term survivors (>5 years, LTS) and short-term survivors (<1 year, STS) with isocitrate dehydrogenase (IDH)-wild-type GBMs. Methods: In a multicenter retrospective analysis, we identified 25 LTS with a histologically confirmed GBM. They were age- and sex-matched to an STS. The methylation profiles of all 50 samples were analyzed with EPIC 850k, classified according to the DKFZ methylation classifier, and the methylation profiles of LTS versus STS were compared. Results: After methylation profiling, 16/25 LTS and 23/25 STS were confirmed to be IDH-wild-type GBMs, all with +7/-10 signature. LTS had significantly increased O6-methylguanine methyltransferase (MGMT) promoter methylation and higher prevalence of FGFR3-TACC3 fusion (P = .03). STS were more likely to exhibit CDKN2A/B loss (P = .01) and higher frequency of NF1 (P = .02) mutation. There were no significant CpGs identified between LTS versus STS at an adjusted P-value of .05. Unadjusted analyses identified key pathways involved in both LTS and STS. The most common pathways were the Hippo signaling pathway and the Wnt pathway in LTS, and GPCR ligand binding and cell-cell signaling in STS. Conclusions: A small group of patients with IDH-wild-type GBM survive more than 5 years. While there are few differences in the global methylation profiles of LTS compared to STS, our study highlights potential pathways involved in GBMs with a good or poor prognosis.

19.
Neuroradiology ; 66(4): 521-530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38347151

RESUMO

PURPOSE: T2-FLAIR mismatch serves as a highly specific but insensitive marker for IDH-mutant (IDHm) astrocytoma with potential limitations in real-world application. We aimed to assess the utility of a broader definition of T2-FLAIR discordance across a cohort of adult-type diffuse lower-grade gliomas (LrGG) to see if specific patterns emerge and additionally examine factors determining deviation from the classic T2-FLAIR mismatch sign. METHODS: Preoperative MRIs of non-enhancing adult-type diffuse LrGGs were reviewed. Relevant demographic, molecular, and MRI data were compared across tumor subgroups. RESULTS: Eighty cases satisfied the inclusion criteria. Highest discordance prevalence and > 50% T2-FLAIR discordance volume were noted with IDHm astrocytomas (P < 0.001), while < 25% discordance volume was associated with oligodendrogliomas (P = 0.03) and IDH-wildtype (IDHw) LrGG (P = 0.004). "T2-FLAIR matched pattern" was associated with IDHw LrGG (P < 0.001) and small or minimal areas of discordance with oligodendrogliomas (P = 0.03). Sensitivity and specificity of classic mismatch sign for IDHm astrocytoma were 25.7% and 100%, respectively (P = 0.06). Retained ATRX expression and/or non-canonical IDH mutation (n = 10) emerged as a significant factor associated with absence of classic T2-FLAIR mismatch sign in IDHm astrocytomas (100%, P = 0.02) and instead had minimal discordance or matched pattern (40%, P = 0.04). CONCLUSION: T2-FLAIR discordance patterns in adult-type diffuse LrGGs exist on a diverging but distinct spectrum of classic mismatch to T2-FLAIR matched patterns. Specific molecular markers may play a role in deviations from classic mismatch sign.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioma , Oligodendroglioma , Adulto , Humanos , Neoplasias Encefálicas/patologia , Estudos Retrospectivos , Isocitrato Desidrogenase/genética , Glioma/patologia , Imageamento por Ressonância Magnética , Astrocitoma/genética , Mutação
20.
Nat Rev Genet ; 25(4): 237-254, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38291236

RESUMO

To contend with the diversity and ubiquity of bacteriophages and other mobile genetic elements, bacteria have developed an arsenal of immune defence mechanisms. Bacterial defences include CRISPR-Cas, restriction-modification and a growing list of mechanistically diverse systems, which constitute the bacterial 'immune system'. As a response, bacteriophages and mobile genetic elements have evolved direct and indirect mechanisms to circumvent or block bacterial defence pathways and ensure successful infection. Recent advances in methodological and computational approaches, as well as the increasing availability of genome sequences, have boosted the discovery of direct inhibitors of bacterial defence systems. In this Review, we discuss methods for the discovery of direct inhibitors, their diverse mechanisms of action and perspectives on their emerging applications in biotechnology and beyond.


Assuntos
Bacteriófagos , Sistemas CRISPR-Cas , Bactérias/genética , Bacteriófagos/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA