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Introduction: Complement factor H (FH) is a major regulator of the complement alternative pathway, its mutations predispose to an uncontrolled activation in the kidney and on blood cells and to secondary C3 deficiency. Plasma exchange has been used to correct for FH deficiency and although the therapeutic potential of purified FH has been suggested by in vivo experiments in animal models, a clinical approved FH concentrate is not yet available. We aimed to develop a purification process of FH from a waste fraction rather than whole plasma allowing a more efficient and ethical use of blood and plasma donations. Methods: Waste fractions from industrial plasma fractionation (pooled human plasma) were analyzed for FH content by ELISA. FH was purified from unused fraction III and its decay acceleration, cofactor, and C3 binding capacity were characterized in vitro. Biodistribution was assessed by high-resolution dynamic PET imaging. Finally, the efficacy of the purified FH preparation was tested in the mouse model of C3 glomerulopathy (Cfh-/- mice). Results: Our purification method resulted in a high yield of highly purified (92,07%), pathogen-safe FH. FH concentrate is intact and fully functional as demonstrated by in vitro functional assays. The biodistribution revealed lower renal and liver clearance of human FH in Cfh-/- mice than in wt mice. Treatment of Cfh-/- mice documented its efficacy in limiting C3 activation and promoting the clearance of C3 glomerular deposits. Conclusion: We developed an efficient and economical system for purifying intact and functional FH, starting from waste material of industrial plasma fractionation. The FH concentrate could therefore constitute possible treatments options of patients with C3 glomerulopathy, particularly for those with FH deficiency, but also for patients with other diseases associated with alternative pathway activation.
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Complemento C3 , Fator H do Complemento , Camundongos Knockout , Fator H do Complemento/metabolismo , Fator H do Complemento/genética , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Estudo de Prova de Conceito , Camundongos Endogâmicos C57BLRESUMO
The study of fossils and mummies has largely benefited from the use of modern noninvasive and nondestructive imaging technologies and represents a fast developing area. In this review, we describe the emerging role of imaging based on Magnetic Resonance (MR) and Computer Tomography (CT) employed for the study of ancient remains and mummies. For each methodology, the state of the art in paleoradiology applications is described, by emphasizing new technologies developed in the field of both CT, such as micro- and nano-CT, dual-energy and multi-energy CT, and MR, with the description of novel dedicated sequences, radiofrequency coils and gradients. The complementarity of CT and MR in paleoradiology is also discussed, by pointing out what MR provides in addition to CT, with an overview on the state of the art of emerging strategies in the use of CT/MR combination for the study of a sample following a multimodal integrated approach.
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Múmias , Múmias/diagnóstico por imagem , Fósseis , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Computadores , Imagem MultimodalRESUMO
The healing process of the tooth extraction socket often leads to significant resorption of the alveolar bone, eventually causing clinical difficulties for future implant-supported rehabilitations. The aim of the present animal study was to evaluate alveolar bone remodeling after tooth extraction in a rabbit model, either with or without the use of a plain collagen plug inside the socket, by means of micro-computed tomography. The study included the micro-tomography analysis of 36 rabbits' incisor extraction sockets, either left empty or filled with a collagen plug. All animals were euthanized in a staggered manner, in order to address molecular, histologic, and radiographic analyses at different time-points, up to 90 days after surgery. The three-dimensional evaluation was carried out using micro-computed tomography technology on excised bone blocks including the alveolus and the contralateral bone. Both linear and volumetric measures were recorded: the percentage of bone volume change (ΔBV) within the region of interest was considered the primary endpoint of the study. The micro-CT analysis revealed mean volumetric changes of -58.1% ± from baseline to 3 months for the control group, and almost no bone loss for the test group, -4.6%. The sockets treated with the collagen plug showed significantly less dimensional resorption, while the natural-healing group showed an evident collapse of the alveolar bone three months after extraction surgery.
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Accurate dynamic three-dimensional (4D) imaging of the heart of small rodents is required for the preclinical study of cardiac biomechanics and their modification under pathological conditions, but technological challenges are met in laboratory practice due to the very small size and high pulse rate of the heart of mice and rats as compared to humans. In 4D X-ray microtomography (4D µCT), the achievable spatio-temporal resolution is hampered by limitations in conventional X-ray sources and detectors. Here, we propose a proof-of-principle 4D µCT platform, exploiting the unique spatial and temporal features of novel concept, all-optical X-ray sources based on Thomson scattering (TS). The main spatial and spectral properties of the photon source are investigated using a TS simulation code. The entire data acquisition workflow has been also simulated, using a novel 4D numerical phantom of a mouse chest with realistic intra- and inter-cycle motion. The image quality of a typical single 3D time frame has been studied using Monte Carlo simulations, taking into account the effects of the typical structure of the TS X-ray beam. Finally, we discuss the perspectives and shortcomings of the proposed platform.
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Tomografia Computadorizada Quadridimensional/métodos , Coração/diagnóstico por imagem , Microtomografia por Raio-X/métodos , Animais , Simulação por Computador , Humanos , Camundongos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Ratos , Roedores , Razão Sinal-RuídoRESUMO
Obesity and cognitive decline can occur in association. Brain dysmetabolism and insulin resistance might be common underlying traits. We aimed to examine the effect of high-fat diet (HFD) on cognitive decline, and of cognitive impairment on food intake and body-weight, and explore efficacy of chronic intranasal insulin (INI) therapy. We used control (C) and triple transgenic mice (3×Tg, a model of Alzheimer's pathology) to measure cerebral mass, glucose metabolism, and the metabolic response to acute INI administration (cerebral insulin sensitivity). Y-Maze, positron emission-computed tomography, and histology were employed in 8 and 14-month-old mice, receiving normal diet (ND) or HFD. Chronic INI therapy was tested in an additional 3×Tg-HFD group. The 3×Tg groups overate, and had lower body-weight, but similar BMI, than diet-matched controls. Cognitive decline was progressive from HFD to 3×Tg-ND to 3×Tg-HFD. At 8 months, brain fasting glucose uptake (GU) was increased by C-HFD, and this effect was blunted in 3×Tg-HFD mice, also showing brain insulin resistance. Brain mass was reduced in 3×Tg mice at 14 months. Dentate gyrus dimensions paralleled cognitive findings. Chronic INI preserved cognition, dentate gyrus and metabolism, reducing food intake, and body weight in 3×Tg-HFD mice. Peripherally, leptin was suppressed and PAI-1 elevated in 3×Tg mice, correlating inversely with cerebral GU. In conclusion, 3×Tg background and HFD exert additive (genes*lifestyle) detriment to the brain, and cognitive dysfunction is accompanied by increased food intake in 3×Tg mice. PAI-1 levels and leptin deficiency were identified as potential peripheral contributors. Chronic INI improved peripheral and central outcomes.
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The external auditory canal (EAC) is an osseocartilaginous structure extending from the auricle to the eardrum, which can be affected by congenital, inflammatory, and neoplastic diseases, thus reconstructive materials are needed. Current biomaterial-based approaches for the surgical reconstruction of EAC posterior wall still suffer from resorption (biological) and extrusion (synthetic). In this study, 3D fiber deposited scaffolds based on poly(ethylene oxide terephthalate)/poly(butylene terephthalate) were designed and fabricated to replace the EAC wall. Fiber diameter and scaffold porosity were optimized, leading to 200 ± 33 µm and 55% ± 5%, respectively. The mechanical properties were evaluated, resulting in a Young's modulus of 25.1 ± 7.0 MPa. Finally, the EAC scaffolds were tested in vitro with osteo-differentiated human mesenchymal stromal cells (hMSCs) with different seeding methods to produce homogeneously colonized replacements of interest for otologic surgery. This study demonstrated the fabrication feasibility of EAC wall scaffolds aimed to match several important requirements for biomaterial application to the ear under the Tissue Engineering paradigm, including shape, porosity, surface area, mechanical properties and favorable in vitro interaction with osteoinduced hMSCs. This study demonstrated the fabrication feasibility of outer ear canal wall scaffolds via additive manufacturing. Aimed to match several important requirements for biomaterial application to ear replacements under the Tissue Engineering paradigm, including shape, porosity and pore size, surface area, mechanical properties and favorable in vitro interaction with osteo-differentiated mesenchymal stromal cells.
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Materiais Biocompatíveis/química , Meato Acústico Externo/citologia , Nanofibras/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Materiais Biocompatíveis/farmacologia , Células Sanguíneas/citologia , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/fisiologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Modelos Anatômicos , Polímeros/síntese química , Polímeros/química , Polímeros/farmacologia , Impressão Tridimensional , Engenharia Tecidual/instrumentaçãoRESUMO
The rapidly growing field of functional, molecular and structural bio-imaging is providing an extraordinary new opportunity to overcome the limits of invasive liver biopsy and introduce a "digital biopsy" for in vivo study of liver pathophysiology. To foster the application of bio-imaging in clinical and translational research, there is a need to standardize the methods of both acquisition and the storage of the bio-images of the liver. It can be hoped that the combination of digital, liquid and histologic liver biopsies will provide an innovative synergistic tri-dimensional approach to identifying new aetiologies, diagnostic and prognostic biomarkers and therapeutic targets for the optimization of personalized therapy of liver diseases and liver cancer. A group of experts of different disciplines (Special Interest Group for Personalized Hepatology of the Italian Association for the Study of the Liver, Institute for Biostructures and Bio-imaging of the National Research Council and Bio-banking and Biomolecular Resources Research Infrastructure) discussed criteria, methods and guidelines for facilitating the requisite application of data collection. This manuscript provides a multi-Author review of the issue with special focus on fatty liver.
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Obesity and diabetes associate with neurodegeneration. Brain glucose and BDNF are fundamental in perinatal development. BDNF is related to brain health, food intake and glucose metabolism. We characterized the relationship between glycemia and/or brain glucose utilization (by 18FDG-PET during fasting and glucose loading), obesity and BDNF in 4-weeks old (pre-obese) and 12-weeks old (obese) Zucker fa/fa rats, and their age-matched fa/+ controls. In 75 human infants, we assessed cord blood BDNF and glucose levels, appetite regulating hormones, body weight and maternal factors. Young and adult fa/fa rats showed glucose intolerance and brain hyper-utilization compared to controls. Glycemia and age were positively related to brain glucose utilization, and were negative predictors of BDNF levels. In humans, fetal glycemia was dependent on maternal glycemia at term, and negatively predicted BDNF levels. Leptin levels were associated with higher body weight and lower BDNF levels. Glucose intolerance and elevated brain glucose utilization already occur in young, pre-obese rats, suggesting that they precede obesity onset in Zucker fatty rats. Glycemic elevation and brain glucose overexposure predict circulating BDNF deficiency since perinatal and early life. Future studies should evaluate whether the control of maternal and fetal glycemia during late intrauterine development can prevent these unfavorable interactions.
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Glicemia/análise , Química Encefálica , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Glucose/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/diagnóstico por imagem , Fator Neurotrófico Derivado do Encéfalo/genética , Feminino , Feto/metabolismo , Fluordesoxiglucose F18 , Genótipo , Glucose/análise , Intolerância à Glucose/metabolismo , Humanos , Hiperglicemia/genética , Hiperglicemia/metabolismo , Lactente , Recém-Nascido , Leptina/sangue , Masculino , Obesidade/metabolismo , Obesidade/fisiopatologia , Tomografia por Emissão de Pósitrons , Ratos , Ratos ZuckerRESUMO
OBJECTIVES: The aim of this study was to investigate the consequences of maternal overweight on cardiac development in offspring in infants (short term) and minipigs (short and longer term). BACKGROUND: The epidemic of overweight involves pregnant women. The uterine environment affects organ development, modulating disease susceptibility. Offspring of obese mothers have higher rates of cardiovascular events and mortality. METHODS: Echocardiography was performed in infants born to lean and overweight mothers at birth and at 3, 6, and 12 months of age. In minipigs born to mothers fed a high-fat diet or a normal diet, cardiac development (echocardiography, histology), glucose metabolism and perfusion (positron emission tomography), triglyceride and glycogen content, and myocardial enzymes regulating metabolism (mass spectrometry) were determined from birth to adulthood. RESULTS: In neonates, maternal overweight, especially in the last trimester, predicted a thicker left ventricular posterior wall at birth (4.1 ± 0.3 vs. 3.3 ± 0.2 mm; p < 0.05) and larger end-diastolic and stroke volumes at 1 year. Minipigs born to mothers fed a high-fat diet showed greater left ventricular mass (p = 0.0001), chambers (+100%; p < 0.001), stroke volume (+75%; p = 0.001), cardiomyocyte nuclei (+28%; p = 0.02), glucose uptake, and glycogen accumulation at birth (+100%; p < 0.005), with lower levels of oxidative enzymes, compared with those born to mothers fed a normal diet. Subsequently, they developed myocardial insulin resistance and glycogen depletion. Late adulthood showed elevated heart rate (111 ± 5 vs. 84 ± 8 beats/min; p < 0.05) and ejection fraction and deficient fatty acid oxidative enzymes. CONCLUSIONS: Neonatal changes in cardiac morphology were explained by late-trimester maternal body mass index; myocardial glucose overexposure seen in minipigs can justify early human findings. Longer term effects in minipigs consisted of myocardial insulin resistance, enzymatic alterations, and hyperdynamic systolic function.
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Ganho de Peso na Gestação , Cardiopatias/etiologia , Obesidade/complicações , Efeitos Tardios da Exposição Pré-Natal , Animais , Modelos Animais de Doenças , Metabolismo Energético , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/metabolismo , Cardiopatias/fisiopatologia , Humanos , Lactente , Recém-Nascido , Resistência à Insulina , Masculino , Miócitos Cardíacos/metabolismo , Obesidade/fisiopatologia , Gravidez , Suínos , Porco Miniatura , Fatores de Tempo , Função Ventricular Esquerda , Remodelação VentricularRESUMO
Enamel thickness figures prominently in studies of human evolution, particularly for taxonomy, phylogeny, and paleodietary reconstruction. Attention has focused on molar teeth, through the use of advanced imaging technologies and novel protocols. Despite the important results achieved thus far, further work is needed to investigate all tooth classes. We apply a recent approach developed for anterior teeth to investigate the 3D enamel thickness of Neandertal and modern human (MH) canines. In terms of crown size, the values obtained for both upper and lower unworn/slightly worn canines are significantly greater in Neandertals than in Upper Paleolithic and recent MH. The 3D relative enamel thickness (RET) is significantly lower in Neandertals than in MH. Moreover, differences in 3D RET values between the two groups appear to decrease in worn canines beginning from wear stage 3, suggesting that both the pattern and the stage of wear may have important effects on the 3D RET value. Nevertheless, the 3D average enamel thickness (AET) does not differ between the two groups. In both groups, 3D AET and 3D RET indices are greater in upper canines than in lower canines, and overall the enamel is thicker on the occlusal half of the labial aspect of the crown, particularly in MH. By contrast, the few early modern humans investigated show the highest volumes of enamel while for all other components of 3D enamel, thickness this group holds an intermediate position between Neandertals and recent MH. Overall, our study supports the general findings that Neandertals have relatively thinner enamel than MH (as also observed in molars), indicating that unworn/slightly worn canines can be successfully used to discriminate between the two groups. Further studies, however, are needed to understand whether these differences are functionally related or are the result of pleiotropic or genetic drift effects.
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Esmalte Dentário/anatomia & histologia , Fósseis/anatomia & histologia , Dente Molar/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Paleodontologia , Dente/anatomia & histologia , Microtomografia por Raio-X/métodos , Animais , Humanos , Imageamento TridimensionalRESUMO
OBJECTIVES: Early evidence for the treatment of dental pathology is found primarily among food-producing societies associated with high levels of oral pathology. However, some Late Pleistocene hunter-gatherers show extensive oral pathology, suggesting that experimentation with therapeutic dental interventions may have greater antiquity. Here, we report the second earliest probable evidence for dentistry in a Late Upper Paleolithic hunter-gatherer recovered from Riparo Fredian (Tuscany, Italy). MATERIALS AND METHODS: The Fredian 5 human consists of an associated maxillary anterior dentition with antemortem exposure of both upper first incisor (I1 ) pulp chambers. The pulp chambers present probable antemortem modifications that warrant in-depth analyses and direct dating. Scanning electron microscopy, microCT and residue analyses were used to investigate the purported modifications of external and internal surfaces of each I1 . RESULTS: The direct date places Fredian 5 between 13,000 and 12,740 calendar years ago. Both pulp chambers were circumferentially enlarged prior to the death of this individual. Occlusal dentine flaking on the margin of the cavities and striations on their internal aspects suggest anthropic manipulation. Residue analyses revealed a conglomerate of bitumen, vegetal fibers, and probable hairs adherent to the internal walls of the cavities. DISCUSSION: The results are consistent with tool-assisted manipulation to remove necrotic or infected pulp in vivo and the subsequent use of a composite, organic filling. Fredian 5 confirms the practice of dentistry-specifically, a pathology-induced intervention-among Late Pleistocene hunter-gatherers. As such, it appears that fundamental perceptions of biomedical knowledge and practice were in place long before the socioeconomic changes associated with the transition to food production in the Neolithic.
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Cárie Dentária/terapia , Restauração Dentária Permanente/história , Cárie Dentária/história , Cárie Dentária/patologia , História da Odontologia , História Antiga , Humanos , Incisivo/patologia , Itália , PaleopatologiaRESUMO
OBJECTIVES: The aim of the study is the assessment of Nadale 1, a Neanderthal deciduous tooth recently discovered in Northeastern Italy in the De Nadale cave (Middle Palaeolithic). Together with the clear archaeological context of the site, this study brings new insight on Neanderthal behavior and dental morphological variability. MATERIALS AND METHODS: We used microCT data to provide a morphological description and morphometric analysis (diameter measurements and dental tissue volumes) of the Nadale 1 human tooth. Microwear analysis, taphonomical investigation and caries identification were performed using a stereomicroscope and Scanning Electron Microscope. RESULTS: In terms of morphology (i.e., incipient tuberculum molare, marked mesial marginal ridge and well-developed mid-trigonid crest connecting the protoconid and the metaconid, deep anterior fovea) and size, Nadale 1 presents features frequently observed in Neanderthal lower first deciduous molars. Microscope investigations reveal the presence of a small pit which could be correlated to an incipient caries. CONCLUSION: Nadale 1 expands the Italian Middle Palaeolithic fossil record and provides further information on Neanderthal dm1s in terms of dimensional and morphological variability. Furthermore, the presence of an incipient caries brings further data on Neanderthal diet.
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Cárie Dentária/patologia , Dente Molar/patologia , Homem de Neandertal , Dente Decíduo/patologia , Animais , Arqueologia , Cavernas , Fósseis , Itália , PaleodontologiaRESUMO
OBJECTIVES: In this contribution, we present a morphological description and comparative morphometric analysis of Cavallo D, a human tooth unearthed from the Mousterian FIII sublayer of Grotta del Cavallo (Apulia, Italy). MATERIALS AND METHODS: We used microCT data to provide a detailed morphological description and morphometric analysis of the Cavallo D human tooth based on traditional diameter measurements and 3D enamel thickness. Moreover, new AMS radiocarbon dating of charcoals from layers FII was carried out. RESULTS: Morphological features observed in Cavallo D align the tooth to Neandertals. Similarly, the large size of the tooth (e.g., BL diameter) and the relatively thinner enamel thickness are typical Neandertal traits. 14 C datings of layer FII attribute the tooth to a time range of 45,600-42,900 cal BP (at 68% level of probability). DISCUSSION: Up to now, the Rdi1 Cavallo D represents the most recent Neandertal human remain in southern Italy related to a radiocarbon dated stratigraphy. Moreover, since deciduous teeth have been less investigated than the permanent ones, this contribution brings new data to increase our knowledge on the variability of the Neandertal deciduous dentition.
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Incisivo/anatomia & histologia , Homem de Neandertal/anatomia & histologia , Dente Decíduo/anatomia & histologia , Animais , Humanos , Itália , Odontometria , PaleodontologiaRESUMO
INTRODUCTION: A2B adenosine receptors (ARs) are commonly defined as "danger" sensors because they are triggered during cell injury when the endogenous molecule, adenosine, increases rapidly. These receptors, together with the other receptor subtypes (A1, A2A and A3), exert a wide variety of immunomodulating and (cyto)protective effects, thus representing a pivotal therapeutic target for different pathologies including diabetes, tumors, cardiovascular diseases, pulmonary fibrosis and others. The limited availability of potent and selective ligands for A2B ARs has prevented this receptor to emerge both as therapeutic and diagnostic target. METHODS: Recently, a new class of potent A2B ARs antagonists was developed featuring the triazinobenzimidazole scaffold. Starting from this chemotype, we synthesized a new radiotracer, [(11)C]-4 (1-[(11)C]methyl-3-phenyl triazino[4,3-a]benzimidazol-4(1H)-one), and investigated the pharmacokinetics of this compound in vivo to define its potential use in the imaging of A2B AR with positron emission tomography. RESULTS: [(11)C]-4 showed a very high chemical and blood stability. Results of in vivo and ex vivo experiments underlined the ability of this molecule to bind the A2B AR and correlated with the A2B AR protein and gene expression data. CONCLUSIONS: Although further studies are necessary, these data suggest that [(11)C]-4 may represent a good lead compound for the development of novel selective and potent A2B AR radiotracers, and a new option for the clinical investigation of several pathophysiological processes and chronic diseases.
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Benzimidazóis/síntese química , Isótopos de Carbono , Tomografia por Emissão de Pósitrons/métodos , Receptor A2B de Adenosina/metabolismo , Triazinas/síntese química , Animais , Benzimidazóis/química , Benzimidazóis/metabolismo , Benzimidazóis/farmacocinética , Células CHO , Cricetinae , Cricetulus , Regulação da Expressão Gênica , Humanos , Marcação por Isótopo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Radioquímica , Ratos , Receptor A2B de Adenosina/genética , Relação Estrutura-Atividade , Distribuição Tecidual , Triazinas/química , Triazinas/metabolismo , Triazinas/farmacocinéticaRESUMO
PURPOSE: The plasma membrane P-glycoprotein (Pgp) is an efflux transporter involved in multidrug resistance and in the onset of neurodegenerative disease. Its function and most mechanisms of action are still under investigation. We developed a C-11-labeled 2-arylethylphenylamine-([11C]AEPH) derivative for positron emission tomography (PET), as a novel probe to better understand the activity and the function of Pgp in vivo. PROCEDURES: The synthetic procedure and the quality control of the selected lead compound, [11C]AEPH-1, were set up and optimized. The biodistribution and the dynamic extraction in target organs of [11C]AEPH-1 were studied in vivo by PET in healthy rats at baseline and after pre-treatment with a Pgp inhibitor (tariquidar). RESULTS: In vivo dynamic imaging was consistent with the results of ex vivo extraction on explanted organs. An adequate stability for in vivo studies, as well as a high activity of [11C]AEPH-1 in intestine and barrier tissues, has been demonstrated. Results of the blockade study showed a decrease of uptake after the pre-treatment, indicating a behavior attributable to a Pgp ligand. CONCLUSIONS: The suitable pharmacokinetics and the specificity tested in the pre-treated animals have indicated the potentiality of this AEPH derivative to act as Pgp ligand, providing new opportunities for further studies on expression and function of this important efflux transporter in the fields of neurology and oncology.
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Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Compostos de Anilina/química , Compostos de Anilina/síntese química , Tomografia por Emissão de Pósitrons/métodos , Animais , Humanos , Masculino , Ratos Wistar , Distribuição TecidualRESUMO
Computed tomography (CT) has long been used for investigating palaeontological specimens, as it is a nondestructive technique which avoids the need to dissolve or ionize the fossil sample. However, magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) have recently gained ground as analytical tools for examination of palaeontological samples, by nondestructively providing information about the structure and composition of fossils. While MRI techniques are able to reveal the three-dimensional geometry of the trace fossil, MRS can provide information on the chemical composition of the samples. The multidimensional nature of MR (magnetic resonance) signals has potential to provide rich three-dimensional data on the palaeontological specimens and also to help in elucidating paleopathological and paleoecological questions. In this work the verified applications and the emerging uses of MRI and MRS in paleontology are reviewed, with particular attention to fossil spores, fossil plants, ambers, fossil invertebrates, and fossil vertebrate studies.
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Fósseis/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , PaleontologiaRESUMO
Nondestructive diagnostic imaging for mummies study has a long tradition and high-resolution images of the samples morphology have been extensively acquired by using computed tomography (CT). However, although in early reports no signal or image was obtained because of the low water content, mummy magnetic resonance imaging (MRI) was demonstrated able to generate images of such ancient specimens by using fast imaging techniques. Literature demonstrated the general feasibility of nonclinical MRI for visualizing historic human tissues, which is particularly interesting for archeology. More recently, multinuclear magnetic resonance spectroscopy (MRS) was demonstrated able to detect numerous organic biochemicals from such remains. Although the quality of these images is not yet comparable to that of clinical magnetic resonance (MR) images, and further research will be needed for determining the full capacity of MR in this topic, the information obtained with MR can be viewed as complementary to the one provided by CT and useful for paleoradiological studies of mummies. This work contains an overview of the state of art of the emerging uses of MRI in paleoradiology.
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Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Múmias/diagnóstico por imagem , Humanos , PaleontologiaRESUMO
AIMS/HYPOTHESIS: Maternal obesity negatively affects fetal development. Abnormalities in brain glucose metabolism are predictive of metabolic-cognitive disorders. METHODS: We studied the offspring (aged 0, 1, 6, 12 months) of minipigs fed a normal vs high-fat diet (HFD), by positron emission tomography (PET) to measure brain glucose metabolism, and ex vivo assessments of brain insulin receptors (IRß) and GLUT4. RESULTS: At birth, brain glucose metabolism and IRß were twice as high in the offspring of HFD-fed than control mothers. During infancy and youth, brain glucose uptake, GLUT4 and IRß increased in the offspring of control mothers and decreased in those of HFD-fed mothers, leading to a 40-85% difference (p < 0.05), and severe glycogen depletion, lasting until adulthood. CONCLUSIONS/INTERPRETATION: Maternal high-fat feeding leads to brain glucose overexposure during fetal development, followed by long-lasting depression in brain glucose metabolism in minipigs. These features may predispose the offspring to develop metabolic-neurodegenerative diseases.
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Encéfalo/embriologia , Encéfalo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Animais , Animais Recém-Nascidos , Feminino , Desenvolvimento Fetal/fisiologia , Insulina/metabolismo , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Receptor de Insulina/metabolismo , SuínosRESUMO
Superparamagnetic iron oxide nanoparticles (SPIONs) have received increasing interest as contrast media in biomedical imaging and innovative therapeutic tools, in particular for loco-regional ablative treatments and drug delivery. The future of therapeutic applications would strongly benefit from improving the capability of the nanostructured constructs to reach the selected target, in particular beyond the intravascular space. Besides the decoration of SPIONs surface with ad hoc bioactive molecules, external magnetic fields are in principle able to remotely influence SPIONs' physiological biodistribution and concentrate them to a specific anatomical region or portion of a tissue. The reduction of SPIONs administered to the body and the need for defining the effective SPIONs local concentration suggest that PET/CT may be a method to quantitatively detect the nanoparticles accumulation in vivo at low concentration and assess their tridimensional distribution in response to an external magnetic field and in relation to the local anatomy highlighted by CT imaging. Here, we report on the possibility to assess the spatial distribution of magnetically-driven radiolabelled SPIONs in a peripheral tissue (mouse thigh) with microPET/CT imaging. To this aim we labelled SPIONs using 18 F-2-fluoro-2-deoxyglucose as a synthon, by chemoselective oxime formation between its open-chain tautomer and nanoparticle amino-groups, and employed microPET/CT imaging to measure the radiolabelled construct biodistribution in a small animal model, following intravenous administration, with and without the application of a permanent magnet onto the skin. The in vivo and ex vivo results showed that micro-PET/CT was able to demonstrate the localizing action of the magnet on SPIONs and provide information, in a multimodal 3D data set, about SPIONs biodistribution taking into account the local anatomy. Copyright © 2017 John Wiley & Sons, Ltd.