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1.
Artigo em Russo | MEDLINE | ID: mdl-34283534

RESUMO

Toxoplasmosis is a widespread parasitic disease. It is caused by an intracellular parasite Toxoplasma gondii. It can affect various tissues and organs, forming cysts and continuing to replicate within them. In people with intact immune system, tissue cysts remain in latent state throughout their whole life. However, in cases of cellular immunodeficiency the infection can be reactivated, which leads to secondary generalization of the process. People with HIV most commonly present with cerebral toxoplasmosis. Non-specific neuroimaging signs, as well as absence of pathognomonic symptoms and specific laboratory data lead to difficulties of cerebral toxoplasmosis diagnosis, particularly in the cases with a history of multiple sclerosis that has similar clinical symptoms and brain MRI data suggesting of tumefactive multiple sclerosis image. A clinical case of cerebral toxoplasmosis in a female patient with multiple sclerosis and HIV infection is described.


Assuntos
Infecções por HIV , Esclerose Múltipla , Toxoplasma , Toxoplasmose Cerebral , Feminino , Infecções por HIV/complicações , Humanos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/diagnóstico por imagem , Neuroimagem , Toxoplasmose Cerebral/complicações , Toxoplasmose Cerebral/diagnóstico
2.
Artigo em Inglês | MEDLINE | ID: mdl-34207432

RESUMO

The optic nerve sheath diameter (ONSD) can help predict the neurologic outcomes of patients with post-cardiac arrest (CA) return of spontaneous circulation (ROSC). We aimed to investigate the effect of ONSD changes before and after CA on neurologic outcomes in patients with ROSC after CA using brain computed tomography (CT). The study included patients hospitalized after CA, who had undergone pre- and post-CA brain CT between January 2001 and September 2020. The patients were divided into good and poor neurologic outcome (GNO and PNO, respectively) groups based on their neurologic outcome at hospital discharge. We performed between-group comparisons of the amount and rate of ONSD changes in brain CT and calculated the area under the curve (AUC) to determine their predictive value for neurologic outcomes. Among the 96 enrolled patients, 25 had GNO. Compared with the GNO group, the PNO group showed a significantly higher amount (0.30 vs. 0.63 mm; p = 0.030) and rate (5.26 vs. 12.29%; p = 0.041) of change. The AUC for predicting PNO was 0.64 (95% confidence interval = 0.53-0.73; p = 0.04), and patients with a rate of ONSD change >27.2% had PNO with 100% specificity and positive predictive value. Hence, ONSD changes may predict neurologic outcomes in patients with post-CA ROSC.


Assuntos
Parada Cardíaca , Nervo Óptico , Humanos , Neuroimagem , Nervo Óptico/diagnóstico por imagem , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X
3.
BMJ Case Rep ; 14(7)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290004

RESUMO

A 63-year-old woman presented with headache, progressive somnolence, neurocognitive decline and urinary incontinence through a year. Medical history was unremarkable except for hypertension and hypercholesterolaemia. Neurological examination was normal. Brain MRI showed findings typical for spontaneous intracranial hypotension (subdural fluid collection, pachymeningeal enhancement, brain sagging) and pituitary tumour. The patient's complaints improved dramatically but temporarily after treatment with each of repeated targeted as well as non-targeted blood patches and a trial with continuous intrathecal saline infusion. Extensive work up including repeated MRI-scans, radioisotope cisternographies, CT and T2-weighted MR myelography could not localise the leakage, but showed minor root-cysts at three levels. Finally, lateral decubitus digital subtraction dynamic myelography with subsequent CT myelography identified a tiny dural venous fistula at the fourth thoracic level. After surgical venous ligation, the patient fully recovered. Awareness of spontaneous dural leaks and their heterogeneous clinical picture are important and demands an extensive workup.


Assuntos
Disfunção Cognitiva , Hipotensão Intracraniana , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Feminino , Humanos , Hipotensão Intracraniana/diagnóstico , Hipotensão Intracraniana/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Mielografia , Neuroimagem
4.
Am J Case Rep ; 22: e932123, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34224551

RESUMO

BACKGROUND Diagnosing cerebral venous thrombosis (CVT) poses significant challenges owing to a nonspecific clinical presentation, poorly correlated laboratory biomarkers, and low sensitivity of non-contrast head computed tomography (CT). We describe a case of missed CVT diagnosis, due to low clinical suspicion and nonrecognition of anemia as a prothrombotic factor, especially during an ulcerative colitis (UC) flare. A recently proposed CVT clinical probability score can guide clinicians in pursuing further neurovascular imaging. CASE REPORT A 35-year-old man, with treatment-naive UC, presented to the Emergency Department (ED) with new-onset diffuse headache, 4 weeks of bloody diarrhea, and weight loss. Initial ED laboratory studies revealed severe anemia and unremarkable non-contrast head CT. Two days later, the patient returned to the ED for worsening headache. Non-contrast head CT revealed a left temporal hypodensity. This was later confirmed as acute ischemia on magnetic resonance imaging (MRI). MR venogram revealed thrombosis of the left transverse and sigmoid sinuses, leading to initiation of therapeutic subcutaneous anticoagulation. Repeat MRI, secondary to worsening headache, revealed the development of petechial hemorrhages within the core of venous ischemia in the left temporal lobe. Therapeutic anticoagulation, along with symptomatic management of UC, led to clinical stabilization. CONCLUSIONS CVT should be suspected in patients with UC, especially in the context of anemia, presenting with new-onset or worsening headaches. Recognizing anemia as a thrombogenic factor is crucial. Diagnosis of CVT is challenging due to non-focal symptoms and poorly correlating diagnostic tests. We endorse implementing the CVT clinical probability score into AHA/ASA CVT guidelines to enhance diagnostic accuracy.


Assuntos
Trombose Intracraniana , Trombose Venosa , Adulto , Cefaleia/etiologia , Humanos , Trombose Intracraniana/diagnóstico , Masculino , Neuroimagem , Flebografia , Trombose Venosa/diagnóstico
5.
Curr Neurol Neurosci Rep ; 21(9): 49, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34268621

RESUMO

PURPOSE OF REVIEW: Traumatic spinal cord injury (SCI) is a life-changing event with drastic implications for patients due to sensorimotor impairment and autonomous dysfunction. Current clinical evaluations focus on the assessment of injury level and severity using standardized neurological examinations. However, they fail to predict individual trajectories of recovery, which highlights the need for the development of advanced diagnostics. This narrative review identifies recent advances in the search of clinically relevant biomarkers in the field of SCI. RECENT FINDINGS: Advanced neuroimaging and molecular biomarkers sensitive to the disease processes initiated by the SCI have been identified. These biomarkers range from advanced neuroimaging techniques, neurophysiological readouts, and molecular biomarkers identifying the concentrations of several proteins in blood and CSF samples. Some of these biomarkers improve current prediction models based on clinical readouts. Validation with larger patient cohorts is warranted. Several biomarkers have been identified-ranging from imaging to molecular markers-that could serve as advanced diagnostic and hence supplement current clinical assessments.


Assuntos
Traumatismos da Medula Espinal , Biomarcadores , Humanos , Neuroimagem , Medula Espinal , Traumatismos da Medula Espinal/diagnóstico
6.
Handb Clin Neurol ; 181: 207-237, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34238459

RESUMO

Central diabetes insipidus (CDI) occurs secondary to deficient synthesis or secretion of arginine vasopressin peptide from the hypothalamo-neurohypophyseal system (HNS). It is characterized by polydipsia and polyuria (urine output >30mL/kg/day in adults and >2l/m2/24h in children) of dilute urine (<250mOsm/L). It can result from any pathology affecting one or more components of the HNS including the hypothalamic osmoreceptors, supraoptic or paraventricular nuclei, and median eminence of the hypothalamus, infundibulum, stalk or the posterior pituitary gland. MRI is the imaging modality of choice for evaluation of the hypothalamic-pituitary axis (HPA), and a dedicated pituitary or sella protocol is essential. CT can provide complimentary diagnostic information and is also of value when MRI is contraindicated. The most common causes are benign or malignant neoplasia of the HPA (25%), surgery (20%), and head trauma (16%). No cause is identified in up to 30% of cases, classified as idiopathic CDI. Knowledge of the anatomy and physiology of the HNS is crucial when evaluating a patient with CDI. Establishing the etiology of CDI with MRI in combination with clinical and biochemical assessment facilitates appropriate targeted treatment. This chapter illustrates the wide variety of causes and imaging correlates of CDI on neuroimaging, discusses the optimal imaging protocols, and revises the detailed neuroanatomy required to interpret these studies.


Assuntos
Diabetes Insípido Neurogênico , Diabetes Insípido , Diabetes Mellitus , Neuro-Hipófise , Adulto , Criança , Diabetes Insípido Neurogênico/diagnóstico por imagem , Diabetes Insípido Neurogênico/etiologia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Hipófise
7.
Artigo em Inglês | MEDLINE | ID: mdl-34199339

RESUMO

Most people recover within months after a mild traumatic brain injury (TBI) or concussion, but some will suffer from long-term fatigue with a reduced quality of life and the inability to maintain their employment status or education. For many people, mental fatigue is one of the most distressing and long-lasting symptoms following an mTBI. No efficient treatment options can be offered. The best method for measuring fatigue today is with fatigue self-assessment scales, there being no objective clinical tests available for mental fatigue. The aim here is to provide a narrative review and identify fatigue in relation to cognitive tests and brain imaging methods. Suggestions for future research are presented.


Assuntos
Concussão Encefálica , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico , Humanos , Fadiga Mental/diagnóstico , Fadiga Mental/etiologia , Neuroimagem , Testes Neuropsicológicos , Qualidade de Vida
8.
Sensors (Basel) ; 21(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207145

RESUMO

The early diagnosis of Alzheimer's disease (AD) can allow patients to take preventive measures before irreversible brain damage occurs. It can be seen from cross-sectional imaging studies of AD that the features of the lesion areas in AD patients, as observed by magnetic resonance imaging (MRI), show significant variation, and these features are distributed throughout the image space. Since the convolutional layer of the general convolutional neural network (CNN) cannot satisfactorily extract long-distance correlation in the feature space, a deep residual network (ResNet) model, based on spatial transformer networks (STN) and the non-local attention mechanism, is proposed in this study for the early diagnosis of AD. In this ResNet model, a new Mish activation function is selected in the ResNet-50 backbone to replace the Relu function, STN is introduced between the input layer and the improved ResNet-50 backbone, and a non-local attention mechanism is introduced between the fourth and the fifth stages of the improved ResNet-50 backbone. This ResNet model can extract more information from the layers by deepening the network structure through deep ResNet. The introduced STN can transform the spatial information in MRI images of Alzheimer's patients into another space and retain the key information. The introduced non-local attention mechanism can find the relationship between the lesion areas and normal areas in the feature space. This model can solve the problem of local information loss in traditional CNN and can extract the long-distance correlation in feature space. The proposed method was validated using the ADNI (Alzheimer's disease neuroimaging initiative) experimental dataset, and compared with several models. The experimental results show that the classification accuracy of the algorithm proposed in this study can reach 97.1%, the macro precision can reach 95.5%, the macro recall can reach 95.3%, and the macro F1 value can reach 95.4%. The proposed model is more effective than other algorithms.


Assuntos
Doença de Alzheimer , Diagnóstico Precoce , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Neuroimagem
9.
Sheng Li Xue Bao ; 73(3): 423-432, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34230944

RESUMO

Chronic pain of knee osteoarthritis (KOA) greatly affects the quality of life and functional activities of patients. It is important to clarify the underlying mechanisms of KOA pain and the analgesic effect of different therapies. Neuroimaging technology has been widely used in the basic and clinical research of pain. In the recent years, neuroimaging technology has played an important role in the basic and clinical research of KOA pain. Increasing evidence demonstrates that chronic pain in KOA includes both nociceptive and neuropathic pain. The neuropathic mechanism involved in KOA pain is complex, which may be caused by peripheral or central sensitization. In this paper, we review the regional changes of brain pathophysiology caused by KOA pain based on magnetic resonance imaging (MRI), electroencephalogram (EEG), magnetoencephalogram (MEG), near-infrared spectroscopy (NIRS) and other neuroimaging techniques. We also discuss the central analgesic mechanism of different KOA therapies, with a focus on the latest achievements in the evaluation and prediction of pain. We hope to provide new thoughts for the treatment of KOA pain, especially in the early and middle stages of KOA.


Assuntos
Dor Crônica , Osteoartrite do Joelho , Dor Crônica/diagnóstico por imagem , Humanos , Neuroimagem , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/diagnóstico por imagem , Qualidade de Vida , Tecnologia
10.
Sheng Li Xue Bao ; 73(3): 433-445, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34230945

RESUMO

Migraine is a neurological disorder characterized by attacks of moderate or severe headache and various neurological symptoms. Acupuncture, as a commonly used non-pharmacological therapy, has the advantage of obvious therapeutic effect and few side effects in the prevention and treatment of migraine. But the underlying mechanism of acupuncture on migraine remains unclear. Recently, advances in neuroimaging technology have helped to objectively assess the effect of acupuncture on treating migraine and offered new opportunities to explore the central mechanism of acupuncture on treating migraine. In order to better understand the current status of neuroimaging studies on the therapeutic mechanism of acupuncture on migraine and shed light on future research, this review aims to overview the neuroimaging studies in recent 10 years from two aspects: (1) Central mechanism of acupuncture on treating acute migraine attack; (2) Central mechanism of acupuncture on preventing migraine attack.


Assuntos
Terapia por Acupuntura , Transtornos de Enxaqueca , Humanos , Transtornos de Enxaqueca/terapia , Neuroimagem
12.
Neuroimage Clin ; 30: 102623, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34215138

RESUMO

Functional neurological disorder (FND) was of great interest to early clinical neuroscience leaders. During the 20th century, neurology and psychiatry grew apart - leaving FND a borderland condition. Fortunately, a renaissance has occurred in the last two decades, fostered by increased recognition that FND is prevalent and diagnosed using "rule-in" examination signs. The parallel use of scientific tools to bridge brain structure - function relationships has helped refine an integrated biopsychosocial framework through which to conceptualize FND. In particular, a growing number of quality neuroimaging studies using a variety of methodologies have shed light on the emerging pathophysiology of FND. This renewed scientific interest has occurred in parallel with enhanced interdisciplinary collaborations, as illustrated by new care models combining psychological and physical therapies and the creation of a new multidisciplinary FND society supporting knowledge dissemination in the field. Within this context, this article summarizes the output of the first International FND Neuroimaging Workgroup meeting, held virtually, on June 17th, 2020 to appraise the state of neuroimaging research in the field and to catalyze large-scale collaborations. We first briefly summarize neural circuit models of FND, and then detail the research approaches used to date in FND within core content areas: cohort characterization; control group considerations; task-based functional neuroimaging; resting-state networks; structural neuroimaging; biomarkers of symptom severity and risk of illness; and predictors of treatment response and prognosis. Lastly, we outline a neuroimaging-focused research agenda to elucidate the pathophysiology of FND and aid the development of novel biologically and psychologically-informed treatments.


Assuntos
Transtorno Conversivo , Doenças do Sistema Nervoso , Humanos , Doenças do Sistema Nervoso/diagnóstico por imagem , Neuroimagem
13.
BMJ Case Rep ; 14(7)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34266817

RESUMO

A 71-year-old woman presented to the emergency room with dysphonia, diplopia, dysphagia and generalised weakness since that day. Neurological examination revealed eye adduction limitation, ptosis, hypoactive reflexes and gait ataxia. Blood and cerebrospinal fluid analysis and brain CT were normal. Electromyography revealed a sensory axonal polyneuropathy. She was diagnosed with Miller-Fisher syndrome (MFS) and started on intravenous immunoglobulin. Two days after intravenous immunoglobulin treatment was completed, she developed a sustained hypertensive profile and presented a generalised tonic-clonic seizure. Brain MRI was suggestive of posterior reversible encephalopathy syndrome (PRES) and supportive treatment was implemented with progressive improvement. PRES may be a possible complication of MFS not only due to autonomic and inflammatory dysfunctions, but also as a consequence of its treatment. Patients with MFS should be maintained under close surveillance, especially in the first days and preferably in intermediate care units.


Assuntos
Síndrome de Miller Fisher , Síndrome da Leucoencefalopatia Posterior , Idoso , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imageamento por Ressonância Magnética , Síndrome de Miller Fisher/complicações , Síndrome de Miller Fisher/diagnóstico , Neuroimagem , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/etiologia
14.
Arq Neuropsiquiatr ; 79(4): 334-342, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-34133514

RESUMO

BACKGROUND: Anosognosia, i.e. lack of awareness of one's own symptoms, is a very common finding in patients with dementia and is related to neuropsychiatric symptoms and worse prognosis. Although dementia with Lewy bodies (DLB) is the second most common form of degenerative dementia, literature on anosognosia in this disease is scarce. OBJECTIVES: This paper aimed to review the current evidence on anosognosia in patients with DLB, including its prevalence in comparison with other neurological conditions, its severity and anatomical correlations. METHODS: Database searches were performed in PubMed, Web of Knowledge and PsycINFO for articles assessing anosognosia in DLB. A total of 243 studies were retrieved, but only six were included in the review. RESULTS: Potential risk of selection, comparison or outcome biases were detected in relation to all the studies selected. Most of the studies used self-report memory questionnaires to assess cognitive complaints and compared their results to scores from informant-based instruments or to participants' cognitive performance in neuropsychological tasks. Subjects with DLB had worse awareness regarding memory than healthy older controls, but the results concerning differences in anosognosia between DLB and Alzheimer's disease (AD) patients were inconsistent across studies. Presence of AD pathology and neuroimaging biomarkers appeared to increase the prevalence of anosognosia in individuals with DLB. CONCLUSION: Anosognosia is a common manifestation of DLB, but it is not clear how its prevalence and severity compare with AD. Co-existence of AD pathology seems to play a role in memory deficit awareness in DLB.


Assuntos
Agnosia , Doença de Alzheimer , Doença por Corpos de Lewy , Biomarcadores , Humanos , Neuroimagem , Testes Neuropsicológicos
15.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 594-601, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34180206

RESUMO

UK Biobank (UKB) is a forward-looking epidemiological project with over 500, 000 people aged 40 to 69, whose image extension project plans to re-invite 100, 000 participants from UKB to perform multimodal brain magnetic resonance imaging. Large-scale multimodal neuroimaging combined with large amounts of phenotypic and genetic data provides great resources to conduct brain health-related research. This article provides an in-depth overview of UKB in the field of neuroimaging. Firstly, neuroimage collection and imaging-derived phenotypes are summarized. Secondly, typical studies of UKB in neuroimaging areas are introduced, which include cardiovascular risk factors, regulatory factors, brain age prediction, normality, successful and morbid brain aging, environmental and genetic factors, cognitive ability and gender. Lastly, the open challenges and future directions of UKB are discussed. This article has the potential to open up a new research field for the prevention and treatment of neurological diseases.


Assuntos
Bancos de Espécimes Biológicos , Neuroimagem , Encéfalo , Reino Unido
16.
Nat Commun ; 12(1): 3452, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103532

RESUMO

Progressive apraxia of speech is a neurodegenerative syndrome affecting spoken communication. Molecular pathology, biochemistry, genetics, and longitudinal imaging were investigated in 32 autopsy-confirmed patients with progressive apraxia of speech who were followed over 10 years. Corticobasal degeneration and progressive supranuclear palsy (4R-tauopathies) were the most common underlying pathologies. Perceptually distinct speech characteristics, combined with age-at-onset, predicted specific 4R-tauopathy; phonetic subtype and younger age predicted corticobasal degeneration, and prosodic subtype and older age predicted progressive supranuclear palsy. Phonetic and prosodic subtypes showed differing relationships within the cortico-striato-pallido-nigro-luysial network. Biochemical analysis revealed no distinct differences in aggregated 4R-tau while tau H1 haplotype frequency (69%) was lower compared to 1000+ autopsy-confirmed 4R-tauopathies. Corticobasal degeneration patients had faster rates of decline, greater cortical degeneration, and shorter illness duration than progressive supranuclear palsy. These findings help define the pathobiology of progressive apraxia of speech and may have consequences for development of 4R-tau targeting treatment.


Assuntos
Apraxias/diagnóstico por imagem , Apraxias/genética , Progressão da Doença , Neuroimagem , Fala , Idoso , Idoso de 80 Anos ou mais , Anisotropia , Apraxias/complicações , Apraxias/patologia , Disfunção Cognitiva/complicações , Imagem de Tensor de Difusão , Feminino , Fluordesoxiglucose F18/química , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neurobiologia , Neurônios/metabolismo , Neurônios/patologia , Patologia Molecular , Tomografia por Emissão de Pósitrons , Proteínas tau/metabolismo
17.
Viruses ; 13(5)2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066524

RESUMO

Patients with COVID-19 can require radiological examination, with chest CT being more frequent than neuro-imaging. The objective is to identify epidemiological, clinical and radiological factors considered as predictors of neurological involvement in patients with COVID-19 assessed by neuroimaging and to describe the neuroimaging findings. This retrospective study was performed with 232 consecutive confirmed COVID-19 patients, from two radiological units, which were divided into two groups: (1) those who underwent a brain CT/MRI scan (n = 35) versus (2) those who did not undergo the brain CT/MRI scan, but underwent only chest CT (n = 197). There was a statistically significant difference with associations regarding the COVID-19 brain scan group for: admission to ICU, greater severity of lung injuries, the use of a mechanical ventilator and sepsis. Statistical tendency was found for chronic renal failure and systemic arterial hypertension. Forty-percent of COVID-19 patients from the brain scan group were abnormal on brain CT and/or brain MRI (22.9% of the cases with bleeding or microbleeding, 8.6% with restricted diffusion lesions). One ischemic stroke case was associated with irregularity at the M1 segment of the right middle cerebral artery. There was a case of left facial nerve palsy with enhancement of the left geniculate ganglia. An analysis of the olfactory bulbs was possible in 12 brain MRIs and 100% had enhancement and/or microbleeding. In conclusion, a more severe COVID-19 disease from ICU, a more severe form of lung disease, the use of mechanical ventilator and sepsis were associated to the COVID-19 patients with neurological involvement who had undergone brain scans. Microvascular phenomenon was a frequent finding in the brain and olfactory bulbs evaluated by neuroimaging.


Assuntos
COVID-19/diagnóstico por imagem , Neuroimagem/métodos , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Brasil/epidemiologia , COVID-19/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Tomografia Computadorizada por Raios X/métodos
18.
Transl Psychiatry ; 11(1): 349, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-34091591

RESUMO

Attention-deficit hyperactivity disorder (ADHD) is a neurological and neurodevelopmental childhood-onset disorder characterized by a persistent pattern of inattentiveness, impulsiveness, restlessness, and hyperactivity. These symptoms may continue in 55-66% of cases from childhood into adulthood. Even though the precise etiology of ADHD is not fully understood, it is considered as a multifactorial and heterogeneous disorder with several contributing factors such as heritability, auxiliary to neurodevelopmental issues, severe brain injuries, neuroinflammation, consanguineous marriages, premature birth, and exposure to environmental toxins. Neuroimaging and neurodevelopmental assessments may help to explore the possible role of genetic variations on ADHD neuropsychobiology. Multiple genetic studies have observed a strong genetic association with various aspects of neuropsychobiological functions, including neural abnormalities and delayed neurodevelopment in ADHD. The advancement in neuroimaging and molecular genomics offers the opportunity to analyze the impact of genetic variations alongside its dysregulated pathways on structural and functional derived brain imaging phenotypes in various neurological and psychiatric disorders, including ADHD. Recently, neuroimaging genomic studies observed a significant association of brain imaging phenotypes with genetic susceptibility in ADHD. Integrating the neuroimaging-derived phenotypes with genomics deciphers various neurobiological pathways that can be leveraged for the development of novel clinical biomarkers, new treatment modalities as well as therapeutic interventions for ADHD patients. In this review, we discuss the neurobiology of ADHD with particular emphasis on structural and functional changes in the ADHD brain and their interactions with complex genomic variations utilizing imaging genetics methodologies. We also highlight the genetic variants supposedly allied with the development of ADHD and how these, in turn, may affect the brain circuit function and related behaviors. In addition to reviewing imaging genetic studies, we also examine the need for complementary approaches at various levels of biological complexity and emphasize the importance of combining and integrating results to explore biological pathways involved in ADHD disorder. These approaches include animal models, computational biology, bioinformatics analyses, and multimodal imaging genetics studies.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Animais , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , Criança , Predisposição Genética para Doença , Variação Genética , Humanos , Neuroimagem
19.
Hum Genet ; 140(8): 1183-1200, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34076780

RESUMO

Dyslexia is a common heritable developmental disorder involving impaired reading abilities. Its genetic underpinnings are thought to be complex and heterogeneous, involving common and rare genetic variation. Multigenerational families segregating apparent monogenic forms of language-related disorders can provide useful entrypoints into biological pathways. In the present study, we performed a genome-wide linkage scan in a three-generational family in which dyslexia affects 14 of its 30 members and seems to be transmitted with an autosomal dominant pattern of inheritance. We identified a locus on chromosome 7q21.11 which cosegregated with dyslexia status, with the exception of two cases of phenocopy (LOD = 2.83). Whole-genome sequencing of key individuals enabled the assessment of coding and noncoding variation in the family. Two rare single-nucleotide variants (rs144517871 and rs143835534) within the first intron of the SEMA3C gene cosegregated with the 7q21.11 risk haplotype. In silico characterization of these two variants predicted effects on gene regulation, which we functionally validated for rs144517871 in human cell lines using luciferase reporter assays. SEMA3C encodes a secreted protein that acts as a guidance cue in several processes, including cortical neuronal migration and cellular polarization. We hypothesize that these intronic variants could have a cis-regulatory effect on SEMA3C expression, making a contribution to dyslexia susceptibility in this family.


Assuntos
Dislexia/genética , Predisposição Genética para Doença , Padrões de Herança , Polimorfismo de Nucleotídeo Único , Semaforinas/genética , Sequência de Bases , Movimento Celular , Cromossomos Humanos Par 7 , Dislexia/diagnóstico por imagem , Dislexia/metabolismo , Dislexia/fisiopatologia , Família , Feminino , Expressão Gênica , Genes Dominantes , Ligação Genética , Loci Gênicos , Estudo de Associação Genômica Ampla , Haplótipos , Humanos , Íntrons , Escore Lod , Masculino , Neuroimagem , Neurônios/metabolismo , Neurônios/patologia , Linhagem , Fenótipo , Semaforinas/deficiência , Sequenciamento Completo do Genoma
20.
J Biomed Nanotechnol ; 17(5): 846-858, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082871

RESUMO

The blood-retina barrier (BRB), analogous to the blood-brain barrier, is a major hurdle for the passage of drugs from the blood to the central nervous system. Here, we designed polymeric nanoparticles from amphiphilic poly-/V-vinylpyrrolidone (Amph-PVP NPs) as a new carrier-system and investigated their ability to pass the BRB using a live In-Vivo neuroimaging system for the retina in rats and ex-vivo wholemounted retinae preparation. Amph-PVP NPs were loaded with hydrophobic fluorescent markers as a surrogate for hydrophobic drugs. Linking these NPs with the hydrophobic fluorescence marker Carboxyfluorescein-succinimidyl-ester (CFSE) to the surface, induced the passage of the cargo into the retina tissue. In particular, we observed a substantial internalization of the CFSE-linked NPs into blood cells. We propose surface- modified Amph-PVP NPs as a potential new nano-carrier platform to target posterior eye and potentially brain diseases while camouflaged by blood cells.


Assuntos
Nanopartículas , Animais , Barreira Hematoencefálica , Neuroimagem , Pirrolidinonas , Ratos , Retina
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