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1.
Int J Pharm ; 660: 124335, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-38897488

RESUMO

Nanoparticle-mediated thermotherapeutic research strives innovative, multifunctional, efficient, and safe treatments. Our study introduces a novel nanoplatform: the hollow magnetic vortex nanorings within a polydopamine layer (HMVNp), which exhibit dual functionality as magnetic and photothermal agents. Utilizing a "Dual-mode" approach, combining an alternating magnetic field (AMF) with near-infrared (NIR) laser irradiation, HMVNp demonstrated a significant enhancement in heating efficacy (58 ± 8 %, SAR = 1441 vs 1032 W/g) over traditional solid magnetite nanoparticles coated with polydopamine (SMNp). The unique geometry larger surface area to volume ratio facilitates efficient magnetic vortex dynamics and enhanced heat transfer. Addressing the challenge of heat resistant heat shock protein (Hsp) expression, encapsulated quercetin (Q) within HMVNp leverages tumor acidity and dual-mode thermal therapy to enhance release, showing a 28.8 ± 6.81 % increase in Q loading capacity compared to traditional SMNp. Moreover, HMVNp significantly improves contrast for both magnetic resonance imaging (MRI) and photoacoustic imaging (PAI), with an approximately 62 % transverse relaxation (R2 = 81.5 vs 31.6 mM-1s-1 [Fe]). In vivo studies showed that while single treatments slowed tumor growth, dual-mode therapy with quercetin significantly reduced tumors and effectively prevented metastases. Our study highlights the potential of HMVNp/Q as a versatile agent in thermotherapeutic interventions, offering improved diagnostic imaging capabilities.


Assuntos
Hipertermia Induzida , Indóis , Imageamento por Ressonância Magnética , Polímeros , Quercetina , Quercetina/administração & dosagem , Quercetina/química , Quercetina/farmacologia , Indóis/química , Indóis/administração & dosagem , Polímeros/química , Animais , Imageamento por Ressonância Magnética/métodos , Hipertermia Induzida/métodos , Camundongos , Nanomedicina Teranóstica/métodos , Linhagem Celular Tumoral , Técnicas Fotoacústicas/métodos , Nanopartículas de Magnetita/química , Humanos , Feminino , Camundongos Nus , Camundongos Endogâmicos BALB C , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/diagnóstico por imagem , Terapia Fototérmica/métodos , Nanopartículas/química
3.
Radiol Case Rep ; 18(1): 368-376, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36411846

RESUMO

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a rare chronic central-nervous-system inflammatory disorder that became known only recently, and the pathogenesis of CLIPPERS remains poorly understood. This report presents clinical and radiological features of a rare case: a young female patient who rapidly died of suspected CLIPPERS. Helpful multiparametric MRI diagnostic criteria are proposed that can help discriminate CLIPPERS from non-CLIPPERS pathologies. We reviewed clinical history, symptoms, quantitative data from brain multiparametric MRI before and after treatment, and histopathological data. Perfusion-weighted imaging revealed a decrease in regional cerebral blood flow by 31% and in cerebral blood volume by 64%, with a moderate increase in transit time and in time to peak by up to 23% in affected pontine and cerebral white matter. As estimated by diffusion tensor imaging, there was elevated density of tracts (n/mm2) and a decrease of fraction anisotropy (×10-3 mm/s2) in the patient's pons as compared to a healthy control: density of tracts = 13.5 vs 12.4 and fraction anisotropy = 0.32 vs 0.45, respectively. Macromolecular proton fraction values proved to be reduced (15.8% and 14.5% in the control, respectively) in the patient's cerebral peduncles by 3% and in the pons by 4.1% and in a periventricular white matter lesion by 6.4% (11.3% in the normal-looking contralateral hemisphere). Based on our findings, we argue that quantitative MRI techniques may be a valuable source of biomarkers and reliable diagnostic criteria and can shed light on the pathogenesis and exact nosological position of this disorder.

4.
PLoS One ; 17(2): e0264395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35226657

RESUMO

This paper describes the effects of the interaction of cerebral fluids (arterial, capillary and venous blood, cerebrospinal fluid) on ventricular wall displacement and periventricular pressure using a mathematical multiphase poroelasticity model for the cerebral parenchyma. The interaction of cerebral fluids is given by a set of four numerical coefficients. A multiple linear regression with interaction is constructed that allows us to quantify the effect of these coefficients on the average ventricular wall displacement. The prevailing influence of an arterial-liquor component was observed. The sets of coefficients associated with such pathological conditions were found: normal pressure hydrocephalus, intracranial hypertension, and replacement ventriculomegaly under a prolonged hypoperfusion.


Assuntos
Ventrículos Cerebrais , Hidrocefalia de Pressão Normal , Modelos Neurológicos , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/fisiopatologia , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/fisiopatologia
5.
Rev Neurosci ; 32(7): 693-705, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33618444

RESUMO

The glymphatic system and meningeal lymphatics have recently been characterized. Glymphatic system is a glia-dependent system of perivascular channels, and it plays an important role in the removal of interstitial metabolic waste products. The meningeal lymphatics may be a key drainage route for cerebrospinal fluid into the peripheral blood, may contribute to inflammatory reaction and central nervous system (CNS) immune surveillance. Breakdowns and dysfunction of the glymphatic system and meningeal lymphatics play a crucial role in age-related brain changes, the pathogenesis of neurovascular and neurodegenerative diseases, as well as in brain injuries and tumors. This review discusses the relationship recently characterized meningeal lymphatic vessels with the glymphatic system, which provides perfusion of the CNS with cerebrospinal and interstitial fluids. The review also presents the results of human studies concerning both the presence of meningeal lymphatics and the glymphatic system. A new understanding of how aging, medications, sleep and wake cycles, genetic predisposition, and even body posture affect the brain drainage system has not only changed the idea of brain fluid circulation but has also contributed to an understanding of the pathology and mechanisms of neurodegenerative diseases.


Assuntos
Sistema Glinfático , Vasos Linfáticos , Doenças Neurodegenerativas , Encéfalo , Sistema Nervoso Central , Humanos
6.
Mol Syndromol ; 8(2): 110-114, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28611553

RESUMO

In this report, we describe a molecular cytogenetic study of a family burdened with intellectual disability (ID) and suicide. Our study revealed that the mother has a heterozygous premutation in the FMR1 gene and supernumerary X chromosomes as well as X-derived marker chromosomes. Both of her sons have ID and a normal chromosome number. One of the sons has fragile X syndrome, and the other has ID of an unclear nature.

7.
J Med Ultrason (2001) ; 42(4): 559-63, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26576982

RESUMO

Using a specific clinical example, we demonstrate the ability of prenatal magnetic resonance imaging (MRI) to diagnose associated spine and spinal cord malformations in the group of spinal dysraphisms. Thus, the original ultrasound (US) and MRI results for the affected fetus at week 21 are illustrated and described in detail. The paucity of reports of prenatal MR-semiotic findings of split cord malformation comparing US and pathomorphological findings at a relatively early gestational age makes the present case unique and instructive. The outstanding capability of MRI to diagnose spinal pathologies indicates the necessity of including prenatal MRI in the diagnostic algorithm to determine the severity of the lesions and the appropriate management during pregnancy, childbirth, and the early postnatal period.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/patologia , Imageamento por Ressonância Magnética , Defeitos do Tubo Neural/diagnóstico por imagem , Defeitos do Tubo Neural/patologia , Diagnóstico Pré-Natal , Coluna Vertebral/anormalidades , Feminino , Morte Fetal , Humanos , Gravidez , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Ultrassonografia , Adulto Jovem
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