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1.
J Alzheimers Dis ; 98(2): 699-713, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38427490

RESUMEN

Background: Alzheimer's disease (AD) is a progressive neurodegenerative disease and symptoms develop gradually over many years. The current direction for medication development in AD is focused on neuro-inflammation and oxidative stress. Amyloid-ß (Aß) deposition activates microglia leading to neuro-inflammation and neurodegeneration induced by activation of COX-2 via NFκB p50 in glioblastoma cells. Objective: The study aimed to evaluate the concentration of COX-2 and NFκB p50 in serum of AD, mild cognitive impairment (MCI), and geriatric control (GC) and to establish a blood-based biomarker for early diagnosis and its therapeutic implications. Methods: Proteins and their mRNA level in blood of study groups were measured by surface plasmon resonance (SPR) and quantitative polymerase chain reaction (qPCR), respectively. The level of protein was further validated by western blot. The binding study of designed peptide against COX-2 by molecular docking was verified by SPR. The rescue of neurotoxicity by peptide was also checked by MTT assay on SH-SY5Y cells (neuroblastoma cell line). Results: Proteins and mRNA were highly expressed in AD and MCI compared to GC. However, COX-2 decreases with disease duration. The peptide showed binding affinity with COX-2 with low dissociation constant in SPR and rescued the neurotoxicity of SH-SY5Y cells by decreasing the level of Aß, tau, and pTau proteins. Conclusions: It can be concluded that COX-2 protein can serve as a potential blood-based biomarker for early detection and can be a good platform for therapeutic intervention for AD.


Asunto(s)
Enfermedad de Alzheimer , Neuroblastoma , Enfermedades Neurodegenerativas , Humanos , Anciano , Enfermedad de Alzheimer/genética , Ciclooxigenasa 2 , Simulación del Acoplamiento Molecular , Péptidos beta-Amiloides/metabolismo , Inflamación/metabolismo , Biomarcadores , Diagnóstico Precoz , ARN Mensajero , Proteínas tau/metabolismo , Fragmentos de Péptidos/uso terapéutico
2.
Neuro Oncol ; 26(1): 127-136, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-37603323

RESUMEN

BACKGROUND: Endovascular selective intra-arterial (ESIA) infusion of cellular oncotherapeutics is a rapidly evolving strategy for treating glioblastoma. Evaluation of ESIA infusion requires a unique animal model. Our goal was to create a rabbit human GBM model to test IA infusions of cellular therapies and to test its usefulness by employing clinical-grade microcatheters and infusion methods to deliver mesenchymal stem cells loaded with an oncolytic adenovirus, Delta-24-RGD (MSC-D24). METHODS: Rabbits were immunosuppressed with mycophenolate mofetil, dexamethasone, and tacrolimus. They underwent stereotactic xenoimplantation of human GBM cell lines (U87, MDA-GSC-17, and MDA-GSC-8-11) into the right frontal lobe. Tumor formation was confirmed on magnetic resonance imaging, histologic, and immunohistochemistry analysis. Selective microcatheter infusion of MSC-D24 was performed via the ipsilateral internal carotid artery to assess model utility and the efficacy and safety of this approach. RESULTS: Twenty-five rabbits were implanted (18 with U87, 2 MDA-GSC-17, and 5 MDA-GSC-8-11). Tumors formed in 68% of rabbits (77.8% for U87, 50.0% for MDA-GSC-17, and 40.0% for MDA-GSC-8-11). On MRI, the tumors were hyperintense on T2-weighted image with variable enhancement (evidence of blood brain barrier breakdown). Histologically, tumors showed phenotypic traits of human GBM including varying levels of vascularity. ESIA infusion into the distal internal carotid artery of 2 ml of MSCs-D24 (107 cells) was safe in the model. Examination of post infusion specimens documented that MSCs-D24 homed to the implanted tumor at 24 hours. CONCLUSIONS: The intracranial immunosuppressed rabbit human GBM model allows testing of ESIA infusion of novel therapeutics (eg, MSC-D24) in a clinically relevant fashion.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Animales , Humanos , Conejos , Glioblastoma/patología , Infusiones Intraarteriales , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Células Madre/patología
3.
J Neurosurg ; 139(4): 1002-1009, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36883646

RESUMEN

OBJECTIVE: Machine learning algorithms have shown groundbreaking results in neuroimaging. The authors herein evaluated the performance of a newly developed convolutional neural network (CNN) to detect and analyze intracranial aneurysms (IAs) on CTA. METHODS: Consecutive patients with CTA studies between January 2015 and July 2021 at a single center were identified. The ground truth determination of cerebral aneurysm presence or absence was made from the neuroradiology report. The primary outcome was the performance of the CNN in detecting IAs in an external validation set, measured using area under the receiver operating characteristic curve statistics. Secondary outcomes included accuracy for location and size measurement. RESULTS: The independent validation imaging data set consisted of 400 patients with CTA studies, median age 40 years (IQR 34 years) and 141 (35.3%) of whom were male; 193 patients (48.3%) had a diagnosis of IA on neuroradiologist evaluation. The median maximum IA diameter was 3.7 mm (IQR 2.5 mm). In the independent validation imaging data set, the CNN performed well with 93.8% sensitivity (95% CI 0.87-0.98), 94.2% specificity (95% CI 0.90-0.97), and a positive predictive value of 88.2% (95% CI 0.80-0.94) in the subgroup with an IA diameter ≥ 4 mm. CONCLUSIONS: The described Viz.ai Aneurysm CNN performed well in identifying the presence or absence of IAs in an independent validation imaging set. Further studies are necessary to investigate the impact of the software on detection rates in a real-world setting.


Asunto(s)
Aneurisma Intracraneal , Humanos , Masculino , Adulto , Femenino , Aneurisma Intracraneal/diagnóstico por imagen , Aprendizaje Automático , Algoritmos , Valor Predictivo de las Pruebas , Estudios Retrospectivos
4.
J Neurosurg ; 138(4): 1077-1084, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36461839

RESUMEN

OBJECTIVE: Machine learning algorithms have shown groundbreaking results in neuroimaging. Herein, the authors evaluate the performance of a newly developed convolutional neural network (CNN) to detect and quantify the thickness, volume, and midline shift (MLS) of subdural hematoma (SDH) from noncontrast head CT (NCHCT). METHODS: NCHCT studies performed for the evaluation of head trauma in consecutive patients between July 2018 and April 2021 at a single institution were retrospectively identified. Ground truth determination of SDH, thickness, and MLS was established by the neuroradiology report. The primary outcome was performance of the CNN in detecting SDH in an external validation set, as measured using area under the receiver operating characteristic curve analysis. Secondary outcomes included accuracy for thickness, volume, and MLS. RESULTS: Among 263 cases with valid NCHCT according to the study criteria, 135 patients (51%) were male, the mean (± standard deviation) age was 61 ± 23 years, and 70 patients were diagnosed with SDH on neuroradiologist evaluation. The median SDH thickness was 11 mm (IQR 6 mm), and 16 patients had a median MLS of 5 mm (IQR 2.25 mm). In the independent data set, the CNN performed well, with sensitivity of 91.4% (95% CI 82.3%-96.8%), specificity of 96.4% (95% CI 92.7%-98.5%), and accuracy of 95.1% (95% CI 91.7%-97.3%); sensitivity for the subgroup with an SDH thickness above 10 mm was 100%. The maximum thickness mean absolute error was 2.75 mm (95% CI 2.14-3.37 mm), whereas the MLS mean absolute error was 0.93 mm (95% CI 0.55-1.31 mm). The Pearson correlation coefficient computed to determine agreement between automated and manual segmentation measurements was 0.97 (95% CI 0.96-0.98). CONCLUSIONS: The described Viz.ai SDH CNN performed exceptionally well at identifying and quantifying key features of SDHs in an independent validation imaging data set.


Asunto(s)
Traumatismos Craneocerebrales , Hematoma Subdural , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Femenino , Estudios Retrospectivos , Hematoma Subdural/diagnóstico por imagen , Aprendizaje Automático , Algoritmos
5.
Front Mol Neurosci ; 15: 1055295, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36533127

RESUMEN

Introduction: Pathologic remodeling of the brain following ischemic stroke results in neuronal loss, increased inflammation, oxidative stress, astrogliosis, and a progressive decrease in brain function. We recently demonstrated that stimulation of steroid receptor coactivator 3 with the small-molecule stimulator MCB-613 improves cardiac function in a mouse model of myocardial ischemia. Since steroid receptor coactivators are ubiquitously expressed in the brain, we reasoned that an MCB-613 derivative (MCB-10-1), could protect the brain following ischemic injury. To test this, we administered MCB-10-1 to rats following middle cerebral artery occlusion and reperfusion. Methods: Neurologic impairment and tissue damage responses were evaluated on day 1 and day 4 following injury in rats treated with control or 10-1. Results: We show that 10-1 attenuates injury post-stroke. 10-1 decreases infarct size and mitigates neurologic impairment. When given within 30 min post middle cerebral artery occlusion and reperfusion, 10-1 induces lasting protection from tissue damage in the ischemic penumbra concomitant with: (1) promotion of reparative microglia; (2) an increase in astrocyte NRF2 and GLT-1 expression; (3) early microglia activation; and (4) attenuation of astrogliosis. Discussion: Steroid receptor coactivator stimulation with MCB-10-1 is a potential therapeutic strategy for reducing inflammation and oxidative damage that cause neurologic impairment following an acute ischemic stroke.

6.
Am J Psychiatry ; 179(11): 853-861, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36000218

RESUMEN

OBJECTIVE: Copy number variants (CNVs) are strongly associated with neurodevelopmental and psychotic disorders. Early-onset psychosis (EOP), where symptoms appear before 18 years of age, is thought to be more strongly influenced by genetic factors than adult-onset psychotic disorders. However, the prevalence and effect of CNVs in EOP is unclear. METHODS: The authors documented the prevalence of recurrent CNVs and the functional impact of deletions and duplications genome-wide in 137 children and adolescents with EOP compared with 5,540 individuals with autism spectrum disorder (ASD) and 16,504 population control subjects. Specifically, the frequency of 47 recurrent CNVs previously associated with neurodevelopmental and neuropsychiatric illnesses in each cohort were compared. Next, CNV risk scores (CRSs), indices reflecting the dosage sensitivity for any gene across the genome that is encapsulated in a deletion or duplication separately, were compared between groups. RESULTS: The prevalence of recurrent CNVs was significantly higher in the EOP group than in the ASD (odds ratio=2.30) and control (odds ratio=5.06) groups. However, the difference between the EOP and ASD groups was attenuated when EOP participants with co-occurring ASD were excluded. CRS was significantly higher in the EOP group compared with the control group for both deletions (odds ratio=1.30) and duplications (odds ratio=1.09). In contrast, the EOP and ASD groups did not differ significantly in terms of CRS. CONCLUSIONS: Given the high frequency of recurrent CNVs in the EOP group and comparable CRSs in the EOP and ASD groups, the findings suggest that all children and adolescents with a psychotic diagnosis should undergo genetic screening, as is recommended in ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastornos Psicóticos , Niño , Adolescente , Adulto , Humanos , Variaciones en el Número de Copia de ADN/genética , Trastorno del Espectro Autista/epidemiología , Trastorno del Espectro Autista/genética , Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/genética , Estudios de Cohortes , Oportunidad Relativa
7.
PeerJ Comput Sci ; 8: e980, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35634100

RESUMEN

When modelling epidemics, the outputs and techniques used may be hard for the general public to understand. This can cause fear mongering and confusion on how to interpret the predictions provided by these models. This article proposes a solution for such a model that was created by a Canadian institute for COVID-19 in their region; namely, the NorthCOVID-19 model. In taking these ethical concerns into consideration, first the web interface of this model is analyzed to see how it may be difficult for a user without a strong mathematical background to understand how to use it. Second, a system is developed that takes this model's outputs as an input and produces a video summarization with an auto-generated audio to address the complexity of the interface, while ensuring that the end user is able to understand the important information produced by this model. A survey conducted on this proposed output asked participants, on a scale of 1 to 5, whether they strongly disagreed (1) or strongly agreed (5) with statements regarding the output of the proposed method. The results showed that the audio in the output was helpful in understanding the results (80% responded with 4 or 5) and that it helped improve overallcomprehension of the model (85% responded with 4 or 5). For the analysis of the NorthCOVID-19 interface, a System Usability Scale (SUS) survey was performed where itreceived a scoring of 70.94 which is slightly above the average of 68.

8.
Anal Chem ; 94(22): 7731-7737, 2022 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-35420426

RESUMEN

Aptamers have been the subject of more than 144 000 papers to date. However, there has been a growing concern that discrepancies in the reporting of aptamer research limit the reliability of these reagents for research and other applications. These observations noting inconsistencies in the use of our RNA antilysozyme aptamer served as an impetus for our systematic review of the reporting of aptamer sequences in the literature. Our detailed examination of the literature citing the RNA antilysozyme aptamer revealed that 93% of the 61 publications reviewed reported unexplained altered sequences with 96% of those using DNA variants. The 10 most cited aptamers were examined using a standardized methodology in order to categorize the extent to which the sequences themselves and altered sequences were adequately described in the literature. Our review of 780 aptamer publications spanned decades, multiple journals, and research groups and revealed that 41% of the papers reported unexplained sequence alterations or omitted sequences. We identified 10 common categories of sequence alterations including deletions, substitutions, and additions, among others. Overall, our findings can be used as a starting point for building better practices in author submissions and publication standards, elevating the rigor and reproducibility of aptamer research.


Asunto(s)
Aptámeros de Nucleótidos , Aptámeros de Nucleótidos/genética , ARN , Reproducibilidad de los Resultados , Técnica SELEX de Producción de Aptámeros/métodos
9.
Mol Psychiatry ; 26(5): 1706-1718, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33597717

RESUMEN

Mendelian and early-onset severe psychiatric phenotypes often involve genetic variants having a large effect, offering opportunities for genetic discoveries and early therapeutic interventions. Here, the index case is an 18-year-old boy, who at 14 years of age had a decline in cognitive functioning over the course of a year and subsequently presented with catatonia, auditory and visual hallucinations, paranoia, aggression, mood dysregulation, and disorganized thoughts. Exome sequencing revealed a stop-gain mutation in RCL1 (NM_005772.4:c.370 C > T, p.Gln124Ter), encoding an RNA 3'-terminal phosphate cyclase-like protein that is highly conserved across eukaryotic species. Subsequent investigations across two academic medical centers identified eleven additional cases of RCL1 copy number variations (CNVs) with varying neurodevelopmental or psychiatric phenotypes. These findings suggest that dosage variation of RCL1 contributes to a range of neurological and clinical phenotypes.


Asunto(s)
Variaciones en el Número de Copia de ADN , Adolescente , Variaciones en el Número de Copia de ADN/genética , Humanos , Masculino , Mutación/genética , Fenotipo , Secuenciación del Exoma
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