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1.
Pediatr Rep ; 15(1): 58-68, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36810338

RESUMO

BACKGROUND: The pandemic of coronavirus disease 2019 (COVID-19) was undoubtedly a stressful experience for everyone. General opinion believed that children with acute or chronic illness could experience additional burden, but this is not confirmed. The aim of this study is to understand how children and adolescents already suffering from acute or chronic illness (e.g., cancer, cystic fibrosis, neuropsychiatric disorders) feel about the COVID-19 pandemic, and if the experience is significantly different between these children and children without illness. METHODS: Children and adolescents affected by acute or chronic illness (named the "fragile group") treated at the Regina Margherita Children Hospital in Italy, were enrolled in the study by filling a questionnaire about their pandemic experiences. Also, a group of children and adolescents without acute or chronic illness (named the "low-risk group") recruited in the emergency department of the hospital, participated in the study in order to compare experiences. RESULTS: The study group was composed of 166 children and adolescents (Median age = 12 yrs; 78% fragile group, 22% low-risk group). Participants experienced a general state of fear of the virus and of a potential infection for both themselves and their families, while feelings and thoughts that interfere with daily functioning were less frequent. The fragile group seems to be more resilient towards the pandemic situation than low-risk group and some differences on the basis of the type of illness were found in the fragile group. CONCLUSIONS: Dedicated psychosocial intervention must be proposed in order to support fragile children and adolescents' well-being during the pandemic, also on the basis of their clinical and mental history.

2.
Int J Mol Sci ; 24(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36834956

RESUMO

An improved understanding of an ovary's structures is highly desirable to support advances in folliculogenesis knowledge and reproductive medicine, with particular attention to fertility preservation options for prepubertal girls with malignant tumors. Although currently the golden standard for structural analysis is provided by combining histological sections, staining, and visible 2D microscopic inspection, synchrotron radiation phase-contrast microtomography is becoming a new challenge for three-dimensional studies at micrometric resolution. To this aim, the proper use of contrast agents can improve the visualization of internal structures in ovary tissues, which normally present a low radiopacity. In this study, we report a comparison of four staining protocols, based on iodine or tungsten containing agents, applied to bovine ovarian tissues fixed in Bouin's solution. The microtomography (microCT) analyses at two synchrotron facilities under different set-ups were performed at different energies in order to maximize the image contrast. While tungsten-based agents allow large structures to be well identified, Iodine ones better highlight smaller features, especially when acquired above the K-edge energy of the specific metal. Further scans performed at lower energy where the setup was optimized for overall quality and sensitivity from phase-contrast still provided highly resolved visualization of follicular and intrafollicular structures at different maturation stages, independent of the staining protocol. The analyses were complemented by X-ray Fluorescence mapping on 2D sections, showing that the tungsten-based agent has a higher penetration in this type of tissues.


Assuntos
Imageamento Tridimensional , Iodo , Humanos , Feminino , Animais , Bovinos , Imageamento Tridimensional/métodos , Microscopia , Raios X , Microtomografia por Raio-X/métodos , Ovário , Tungstênio , Meios de Contraste/química
3.
Med Phys ; 50(3): 1601-1613, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36309985

RESUMO

BACKGROUND: The formation of concrements in human pineal gland (PG) is a physiological process and, according to many researchers, is associated with the involution of PG structures. The majority of scientific publications concern progressive calcification of PG, leaving out studies on the destruction of already formed calcified concrements. Our study fills the gap in knowledge about calcified zones destruction in PG in normal aging and neuropathological conditions, which has not been addressed until now. PURPOSE: Our objective is to gain insight into human PG tissue impairment in both normal aging and neurodegenerative conditions. X-ray phase-contrast tomography (XPCT) allowed us to study PG tissue degeneration at high spatial resolution and, for the first time, to examine the damaged PG concrements in detail. Our research finding could potentially enhance the understanding of the PG involvement in the process of aging as well as in Alzheimer's disease (AD) and vascular dementia (VD). METHODS: The research was carried out on human PG autopsy material in normal aging, VD, and AD conditions. Laboratory-based micro-computed tomography (micro-CT) was used to collect and evaluate samples of native, uncut, and unstained PG with different degrees of pineal calcification. The detailed high-resolution 3D images of the selected PGs were produced using synchrotron-based XPCT. Histology and immunohistochemistry of soft PG tissue confirmed XPCT results. RESULTS: We performed via micro-CT the evaluation of the morphometric parameters of PG such as total sample volume, calcified concrements volume, and percentage of concrements in the total volume of the sample. XPCT imaging revealed high-resolution details of age-related PG alteration. In particular, we noted signs of moderate degradation of concrements in some PGs from elderly donors. In addition, our analysis revealed noticeable degenerative change in both concrements and soft tissue of PGs with neuropathology. In particular, we observed a hollow core and separated layers as well as deep ragged cracks in PG concrements of AD and VD samples. In parenchyma of some samples, we detected wide pinealocyte-free fluid-filled areas adjacent to the calcified zones. CONCLUSION: The present work provides the basis for future scientific research focused on the dynamic nature of PG calcium deposits and PG soft tissue in normal aging and neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Calcinose , Doenças Neurodegenerativas , Glândula Pineal , Humanos , Idoso , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/metabolismo , Glândula Pineal/patologia , Microtomografia por Raio-X , Doenças Neurodegenerativas/diagnóstico por imagem , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Calcinose/diagnóstico por imagem , Calcinose/patologia
4.
Front Oncol ; 11: 554668, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113554

RESUMO

Characterizing nanoparticles (NPs) distribution in multiple and complex metastases is of fundamental relevance for the development of radiological protocols based on NPs administration. In the literature, there have been advances in monitoring NPs in tissues. However, the lack of 3D information is still an issue. X-ray phase-contrast tomography (XPCT) is a 3D label-free, non-invasive and multi-scale approach allowing imaging anatomical details with high spatial and contrast resolutions. Here an XPCT qualitative study on NPs distribution in a mouse brain model of melanoma metastases injected with gadolinium-based NPs for theranostics is presented. For the first time, XPCT images show the NPs uptake at micrometer resolution over the full brain. Our results revealed a heterogeneous distribution of the NPs inside the melanoma metastases, bridging the gap in spatial resolution between magnetic resonance imaging and histology. Our findings demonstrated that XPCT is a reliable technique for NPs detection and can be considered as an emerging method for the study of NPs distribution in organs.

5.
Nanoscale ; 10(39): 18657-18664, 2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30264838

RESUMO

We report in this study the in vivo biodistribution of ultra-small luminescent gold (Au) particles (∼1.5 nm core size; 17 kDa), so-called nanoclusters (NCs), stabilized by bidentate zwitterionic molecules in subcutaneous (s.c.) and orthotopic glioblastoma mice models. Particular investigations on renal clearance and tumor uptake were performed using highly sensitive advanced imaging techniques such as multi-elemental Laser-Induced Breakdown Spectroscopy (LIBS) imaging and in-line X-ray Synchrotron Phase Contrast Tomography (XSPCT). Results show a blood circulation time of 6.5 ± 1.3 min accompanied by an efficient and fast renal clearance through the cortex of the kidney with a 66% drop between 1 h and 5 h. With a similar size range, these Au NCs are 5 times more fluorescent than the well-described Au25GSH18 NCs in the near-infrared (NIR) region and present significantly stronger tumor uptake and retention illustrated by an in vivo s.c. tumor-to-skin ratio of 1.8 measured by non-invasive optical imaging and an ex vivo tumor-to-muscle of 6.1. This work highlights the pivotal role of surface coating in designing optimum Au NC candidates for cancer treatment.


Assuntos
Meios de Contraste , Glioblastoma/diagnóstico por imagem , Ouro , Nanopartículas Metálicas , Neoplasias Experimentais/diagnóstico por imagem , Tomografia Óptica , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacologia , Feminino , Ouro/química , Ouro/farmacologia , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos , Camundongos Nus , Tomografia por Raios X
6.
Colloids Surf B Biointerfaces ; 148: 615-621, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27694051

RESUMO

Resveratrol is a natural polyphenol found in various plants with potential therapeutic activity as anti-oxidant, anti-inflammatory, cardioprotective and anti-tumoral. Lipid membranes are among cellular components that are targets of its action. In this work ESR of chain labeled lipids, calorimetry, X-ray diffraction and molecular docking are used to study the interaction of resveratrol with membrane model systems of dipalmitoylphosphatidylcholine (DPPC) as a function of resveratrol concentration (0-30 mol% of the lipid) and temperature (10-50°C). Resveratrol incorporated in DPPC bilayers induces considerable motional restriction at the lipid tail termini, removing the gradient of increasing mobility along the chain found in DPPC bilayers in the gel phase. In contrast, it leaves unperturbed the DPPC chain flexibility profile in the liquid-crystalline phase. At low concentration, resveratrol progressively reduces the pre-transition temperature and eliminates the pre-transition for content ≥5mol%. A reduced cooperativity and a downshift of the main transition temperature are observed, especially at high content. The typical diffraction pattern of DPPC multibilayers in the Lß' phase is converted to a lamellar pattern with reduced d-spacing of untilted lipid chain in a hexagonal packing at 30 mol% of resveratrol. Molecular docking indicates that the energetically favoured anchoring site is the polar headgroup region, where resveratrol acts as a spacer. The overall results are consistent with the formation in DPPC of an interdigitated Lßi gel phase induced by 30 mol% resveratrol.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Lipídeos de Membrana/química , Estilbenos/química , 1,2-Dipalmitoilfosfatidilcolina/metabolismo , Fenômenos Biofísicos , Varredura Diferencial de Calorimetria , Membrana Celular/química , Membrana Celular/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Géis/química , Bicamadas Lipídicas/metabolismo , Cristais Líquidos/química , Lipídeos de Membrana/metabolismo , Simulação de Acoplamento Molecular , Transição de Fase , Resveratrol , Estilbenos/metabolismo , Temperatura de Transição , Difração de Raios X
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