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1.
Methods Mol Biol ; 2246: 225-236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33576992

RESUMO

Microautoradiography (MAR) is a technique by which assimilated radioactive tracers incorporated into the biomass can be detected by a film emulsion. This allows for the testing of cellular preferences in electron donors and acceptors of individual cells in complex microbial assemblages, as well as the ability to take up substrates under diverse environmental exposures.Combination with staining techniques such as fluorescence in situ hybridization (FISH) can be used to identify the involved cells. Here, the practical aspects of a combined microautoradiography and fluorescence in situ hybridization (MAR-FISH) approach are described.


Assuntos
Autorradiografia/métodos , Hibridização in Situ Fluorescente/métodos , Biomassa , Elétrons , Microbiota/genética , Filogenia
2.
J Environ Radioact ; 228: 106514, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33360423

RESUMO

Understanding the movement of radionuclides (RNs) between different mineral hosts during processing of base metal ores is critical for accurate modelling of RN deportment and optimisation of processes designed to reduce or eliminate RNs. Here, we demonstrate that spatially resolving quantitative alpha particle autoradiography combined with backscatter electron imaging and energy dispersive X-ray spectroscopy (EDS) can establish the correlation between alpha-emitting RNs (notably 226Ra and 210Po, daughters of the abundant 238U decay series) and certain minerals, in different stages of processing. This is achieved by locating the RNs to a specific mineral grain, the species of which can subsequently be identified using EDS. The mineralogy of RN-associated grains can then be compared with the mineral suite and relative abundances of the species within the sample, by relating how often each mineral is associated with alpha decay-events. In the processing of uranium-bearing copper ores, migration of alpha-emitting RN daughters of the 238U series were observed, and these RNs were demonstrated to correlate strongly with barite, bornite and covellite over other coexisting minerals.


Assuntos
Partículas alfa , Monitoramento de Radiação , Radioisótopos , Autorradiografia , Minerais/análise , Sulfetos
3.
Methods Mol Biol ; 2201: 109-116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32975793

RESUMO

The opioid receptors have been an interesting target for the drug industry for decades. These receptors were pharmacologically characterized in the 1970s and several drugs and peptides have emerged over the years. In 2012, the crystal structures were also demonstrated, with new data on the receptor sites, and thus new possibilities will appear. The role of opioids in the brain has attracted considerable interest in several diseases, especially pain and drug dependence. The opioid receptors are G-protein-coupled receptors (GPCR ) that are Gi coupled which make them suitable for studying the receptor functionality. The [35S]GTP γS autoradiography assay is a good option that has the benefit of generating both anatomical and functional data in the area of interest. It is based on the first step of the signaling mechanism of GPCRs. When a ligand binds to the receptor GTP will replace GDP on the a-subunit of the G-protein, leading to a dissociation of the ßγ-subunit. These subunits will start a cascade of second messengers and subsequently a physiological response.


Assuntos
Autorradiografia/métodos , Guanosina 5'-O-(3-Tiotrifosfato)/química , Receptores Opioides mu/metabolismo , Analgésicos Opioides/metabolismo , Animais , Proteínas de Ligação ao GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Humanos , Receptores Opioides/metabolismo , Transdução de Sinais , Radioisótopos de Enxofre/química , Radioisótopos de Enxofre/metabolismo
4.
Int J Nanomedicine ; 15: 6137-6152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32884268

RESUMO

Background: Beyond clinical atherosclerosis imaging of vessel stenosis and plaque morphology, early detection of inflamed atherosclerotic lesions by molecular imaging could improve risk assessment and clinical management in high-risk patients. To identify inflamed atherosclerotic lesions by molecular imaging in vivo, we studied the specificity of our radiotracer based on maleylated (Mal) human serum albumin (HSA), which targets key features of unstable atherosclerotic lesions. Materials and Methods: Mal-HSA was radiolabeled with a positron-emitting metal ion, zirconium-89 (89Zr4+). The targeting potential of this probe was compared with unspecific 89Zr-HSA and 18F-FDG in an experimental model of atherosclerosis (Apoe-/- mice, n=22), and compared with wild-type (WT) mice (C57BL/6J, n=21) as controls. Results: PET/MRI, gamma counter measurements, and autoradiography showed the accumulation of 89Zr-Mal-HSA in the atherosclerotic lesions of Apoe-/- mice. The maximum standardized uptake values (SUVmax) for 89Zr-Mal-HSA at 16 and 20 weeks were 26% and 20% higher (P<0.05) in Apoe-/- mice than in control WT mice, whereas no difference in SUVmax was observed for 18F-FDG in the same animals. 89Zr-Mal-HSA uptake in the aorta, as evaluated by a gamma counter 48 h postinjection, was 32% higher (P<0.01) for Apoe-/- mice than in WT mice, and the aorta-to-blood ratio was 8-fold higher (P<0.001) for 89Zr-Mal-HSA compared with unspecific 89Zr-HSA. HSA-based probes were mainly distributed to the liver, spleen, kidneys, bone, and lymph nodes. The phosphor imaging autoradiography (PI-ARG) results corroborated the PET and gamma counter measurements, showing higher accumulation of 89Zr-Mal-HSA in the aortas of Apoe-/- mice than in WT mice (9.4±1.4 vs 0.8±0.3%; P<0.001). Conclusion: 89Zr radiolabeling of Mal-HSA probes resulted in detectable activity in atherosclerotic lesions in aortas of Apoe-/- mice, as demonstrated by quantitative in vivo PET/MRI. 89Zr-Mal-HSA appears to be a promising diagnostic tool for the early identification of macrophage-rich areas of inflammation in atherosclerosis.


Assuntos
Aterosclerose/diagnóstico por imagem , Maleatos/química , Imagem Molecular/métodos , Radioisótopos , Albumina Sérica Humana/química , Zircônio , Animais , Aorta/diagnóstico por imagem , Aorta/patologia , Aterosclerose/patologia , Autorradiografia , Modelos Animais de Doenças , Feminino , Fluordesoxiglucose F18 , Humanos , Marcação por Isótopo , Macrófagos/patologia , Imagem por Ressonância Magnética , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/patologia , Tomografia por Emissão de Pósitrons , Radioisótopos/química , Radioisótopos/farmacocinética , Compostos Radiofarmacêuticos/química , Distribuição Tecidual , Zircônio/química , Zircônio/farmacocinética
5.
J Environ Radioact ; 220-221: 106274, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32560879

RESUMO

In highly permeable sedimentary rock formations, U extraction by in-situ leaching techniques (ISR - In-Situ Recovery) is generally considered to have a limited environmental impact at ground level. Significantly, this method of extraction produces neither mill tailings nor waste rocks. Underground, however, the outcome for 238U daughter elements in aquifers is not well known because of their trace concentrations in the host rocks. Thus, understanding the in-situ mobility of these elements remains a challenge. Two samples collected before and after six months of ISR experiments (Dulaan Uul, Mongolia) were studied with the help of a digital autoradiography technique (DA) of alpha particles, bulk alpha spectrometry, and complementary petrographic observation methods. These techniques demonstrate that before and after leaching, the radioactivity is concentrated in altered and microporous Fe-Ti oxides. Most of the daughter elements of U remain trapped in the rock after the leaching process. DA confirms that the alpha activity of the Fe-Ti oxides remains high after uranium leaching, and the initial secular equilibrium of the 238U series for 230Th to 210Po daughter elements (including 226Ra) of the fresh rocks is maintained after leaching. While these findings should be confirmed by more systematic studies, they already identify potential mechanisms explaining why the U-daughter concentrations in leaching water are low.


Assuntos
Autorradiografia , Mongólia , Urânio
6.
J Environ Radioact ; 217: 106211, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32217244

RESUMO

The ability of the autoradiographic device BeaQuant™ is evaluated herein to quantitatively map the ultratrace element 226Ra distributed spatially in celestine (SrSO4) grains/crystals. 226Ra doped celestines have been obtained from coprecipitation and recrystallization experiments, and have been characterized with high purity germanium gamma detector (HPGe), giving specific activities ranging from 3251 to 32523 Bq.g-1. Alpha autoradiographs of polished sections from doped celestines have been obtained using BeaQuant™. These alpha maps have been compared to the celestine grains/crystals arrangement observed with a scanning electron microscope (SEM). At the sample scale, celestine grains are responsible of an alpha signal, indicating that 226Ra is detectable in celestine from its alpha emissions. 226Ra distribution has also been investigated at the celestine grains/crystals scale: the crystal/grain properties do not allow to decide if the distribution process is homogeneous or not, i.e. if there is a chemical zoning into the crystal/grain. The counting of alpha particles by autoradiography has been compared with the total activity of the 226Ra doped celestines by gamma counting (HPGe technique). This comparison was performed by standardizing the measured activities to the same celestine volume, which has been determined by performing a threshold on SEM grey level images to assess to the celestine surface and using Geant4 Monte Carlo simulation toolkit to assess to the emission depth of the particles in celestine. A very good linear correlation between gamma activity and alpha counting from autoradiographs is obtained for all the samples, demonstrating the ability of BeaQuant™ to quantify 226Ra in any points of the millimetric section samples, at a resolution of 20 µm.


Assuntos
Autorradiografia , Partículas alfa , Raios gama , Método de Monte Carlo , Monitoramento de Radiação , Rádio (Elemento)
7.
Ann Neurol ; 87(3): 329-338, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31953875

RESUMO

OBJECTIVE: Parkinson disease is characterized by motor and nonmotor symptoms, reduced striatal dopamine signaling, and loss of dopamine neurons in the substantia nigra. It is now known that the pathological process in Parkinson disease may begin decades before the clinical diagnosis and include a variety of neuronal alterations in addition to the dopamine system. METHODS: This study examined the density of all synapses with synaptic vesicle glycoprotein 2A (SV2A) in Parkinson disease subjects with mild bilateral disease (n = 12) and matched normal controls (n = 12) using in vivo high-resolution positron emission tomographic imaging as well as postmortem autoradiography in an independent sample with Parkinson disease (n = 15) and normal controls (n = 13) in the substantia nigra and putamen. RESULTS: A group-by-brain region interaction effect (F10, 22 = 3.52, p = 0.007) was observed in the primary brain areas with in vivo SV2A binding. Post hoc analyses revealed that the Parkinson disease group exhibited lower SV2A in the substantia nigra (-45%; p < 0.001), red nucleus (-31%; p = 0.03), and locus coeruleus (-17%; p = 0.03). Exploratory analyses also revealed lower SV2A binding in clinically relevant cortical areas. Using autoradiography, we confirmed lower SV2A in the substantia nigra (-17%; p < 0.005) and nonsignificant findings in the putamen (-4%; p = 0.06). INTERPRETATION: This work provides the first evidence of synaptic loss in brainstem nuclei involved in the pathogenesis of Parkinson disease in living patients. SV2A imaging holds promise for understanding synaptic changes central to the disease. Ann Neurol 2020;87:329-338.


Assuntos
Diagnóstico Precoce , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Putamen/patologia , Substância Negra/patologia , Sinapses/patologia , Autorradiografia , Estudos de Casos e Controles , Feminino , Neuroimagem Funcional , Humanos , Locus Cerúleo/patologia , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Tomografia por Emissão de Pósitrons , Putamen/metabolismo , Piridinas , Pirrolidinas , Núcleo Rubro/patologia , Substância Negra/metabolismo
8.
Health Phys ; 118(2): 149-161, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31517652

RESUMO

INTRODUCTION: A study of Pb contamination caused by the outgassing of Rn from Ra in dry, liquid, and murine tissues samples has been made to help design proper handling procedures for Ra in preclinical biodistribution work. MATERIALS AND METHODS: Pb activity levels were measured from Ra in dry, liquid, and tissue samples using aspiration and autoradiography techniques. RESULTS: Using aspiration techniques on dry samples of Ra, an average Rn outgassing rate of 51% ± 21% was measured with one measurement reaching as high as 81%. 31% ± 4% Pb contamination was measured within a 4.3 cm radius of a dry Ra source placed inside a 10-cm-diameter petri dish where the lip of the petri dish contained the Rn dissemination. Without the containment of the petri dish, Rn can reach as far as 7.8 cm from the source with trace levels spreading further. Using aspiration techniques on liquid samples of Ra, outgassing rates of Rn were 0.9% ± 0.3%. The outgassing levels in harvested organs from a biodistribution were as high as 10.1% ± 0.4% for an intraperitoneally injected mouse and 0.204% ± 0.006% for an intravenously injected mouse. The outgassing of the intravenously injected mouse carcass was less than 0.1%. CONCLUSION: In dry form, the high levels of Rn outgassing from a Ra source necessitate the use of ventilated biohoods when handling or preparing dry Ra from source vials. The very low levels of Rn outgassing from Ra liquid sources reduces exposure to Rn by a factor of 50. Rn exposure from murine organ tissue reaches levels of 10% when handling organs from an intraperitoneal injection and less than 0.2% for an intravenous injection.


Assuntos
Radioisótopos de Chumbo/análise , Rádio (Elemento)/análise , Radônio/análise , Animais , Autorradiografia , Feminino , Camundongos , Distribuição Tecidual
9.
Environ Sci Pollut Res Int ; 27(4): 3756-3767, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31300987

RESUMO

Commercial and medicinal applications of functionalized carbon nanotubes (f-CNTs) such as amidated f-CNTs are expanding rapidly with a potential risk exposure to living organisms. The effects of amidated f-CNTs on aquatic species have received a limited attention. In this work, an easy wet method to prepare [14C]-label amide multi-walled carbon nanotubes (MWNTs) is reported. Labeled carbon nanotubes were prepared by successive reactions of carboxylation, chloroacylation, and final amidation using [14C]-labeled ethanolamine. The f-CNTs were characterized using elemental analysis, electron dispersive X-ray, transmission electron microscopy, thermogravimetric analysis, and Raman and FTIR spectroscopy. An uptake experiment was carried out with juvenile Arctic char (Salvelinus alpinus) using water dispersed amidated [14C]-f-CNTs to assess their biodistribution in fish tissues using whole body autoradiography. The radioactivity pattern observed in fish head suggests that f-CNTs were accumulated in head bone canals, possibly involving an interaction with mineral or organic phases of bones such as calcium and collagen. This f-CNTs distribution illustrates how important is to consider the surface charges of functionalized carbon nanotubes in ecotoxicological studies.


Assuntos
Amidas/química , Autorradiografia/métodos , Nanotubos de Carbono , Animais , Bioacumulação , Nanotubos de Carbono/química , Distribuição Tecidual
10.
Cold Spring Harb Protoc ; 2019(12)2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792140

RESUMO

In some cases, a native protein can be isolated in its pure form from cell lysates or tissue preparation using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Antigens purified this way often induce good antibody responses. After electrophoresis, the band of protein of interest must be located in the gel. A variety of identification methods can be used, all of which are designed to avoid excessive fixation of the protein in the gel matrix. The choice of method depends partly on the abundance of the polypeptide. Three methods are commonly used: (1) staining side strips cut from the edge of the gel, (2) light staining of the gel itself, and (3) locating the band by radioactive labeling of the antigen. Staining strips of the gel cut from its sides avoids the need to fix the gel. When isolating abundant proteins that are well separated from other bands, staining side strips is a useful method. If the protein is not abundant or is located close to a contaminating band making a clean excision difficult, use one of the other staining methods. If the protein is reasonably abundant, then a light staining of the proteins in the gel with Coomassie Blue G will permit localization without fixing. Alternatively, the bands in the gel can be visualized by immersing the gel in sodium acetate or copper chloride. If the protein is radiolabeled with 125I, 32P, or 35S, then use an autoradiogram as a template to excise the band of interest.


Assuntos
Antígenos/análise , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/análise , Autorradiografia , Coloração e Rotulagem
11.
Sci Rep ; 9(1): 19560, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31863037

RESUMO

There is a need for new targets to specifically localize inflammatory foci, usable in a wide range of organs. Here, we hypothesized that the cleaved molecular form of CD31 is a suitable target for molecular imaging of inflammation. We evaluated a bioconjugate of D-P8RI, a synthetic peptide that binds all cells with cleaved CD31, in an experimental rat model of sterile acute inflammation. Male Wistar rats were injected with turpentine oil into the gastrocnemius muscle two days before 99mTc-HYNIC-D-P8RI (or its analogue with L-Proline) SPECT/CT or [18F]FDG PET/MRI. Biodistribution, stability study, histology, imaging and autoradiography of 99mTc-HYNIC-D-P8RI were further performed. Biodistribution studies revealed rapid elimination of 99mTc-HYNIC-D-P8RI through renal excretion with almost no uptake from most organs and excellent in vitro and in vivo stability were observed. SPECT/CT imaging showed a significant higher 99mTc-HYNIC-D-P8RI uptake compared with its analogue with L-Proline (negative control) and no significant difference compared with [18F]FDG (positive control). Moreover, autoradiography and histology revealed a co-localization between 99mTc-HYNIC-D-P8RI uptake and inflammatory cell infiltration. 99mTc-HYNIC-D-P8RI constitutes a new tool for the detection and localization of inflammatory sites. Our work suggests that targeting cleaved CD31 is an attractive strategy for the specific in vivo imaging of inflammatory processes.


Assuntos
Inflamação/diagnóstico por imagem , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Animais , Autorradiografia , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Imagem por Ressonância Magnética , Masculino , Microscopia de Fluorescência , Tomografia por Emissão de Pósitrons , Ligação Proteica , Ratos , Ratos Wistar , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único
12.
Nucl Med Biol ; 76-77: 28-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31678899

RESUMO

INTRODUCTION: Hydrogen sulfide (H2S) defined as the third gasotransmitter after nitric oxide (NO) and carbon monoxide (CO) is an important mediator of various physiological functions. Although various H2S-imaging techniques using fluorescence and luminescence have been developed, only one radionuclide imaging using 64Cu-labeled cyclen complex was reported. Thus, we tried to develop 99mTc-labeled H2S imaging agents. METHODS: Various α-hydroxy acids such as glycolate, L-lactate, D-lactate, D-gluconate, D-glucoheptonate, D-glucuronate, D-glucarate, and citrate were labeled with 99mTc in the presence of stannous chloride. The labeled compounds were incubated with 0.2 mM of NaHS, and reactive sulfur species and then analyzed by ITLC/normal saline to detect the formation of insoluble complex. Matrigels containing various concentrations of NaHS were xenografted on the shoulder of normal mice, and an imaging study was performed after intravenous injection of [99mTc]Tc-gluconate. We also obtained autoradiography image of a rat brain with a temporary brain ischemia after intravenous injection of [99mTc]Tc-gluconate. RESULTS: [99mTc]Tc-gluconate showed the highest formation of insoluble complex (87.8 ±â€¯3.6%) after incubation with 0.2 mM NaHS. The other reactive species such as glutathione, cysteine, sulfite, sulfate, thiosulfate, and NO did not form insoluble complex representing the reaction being specific to H2S. The Matrigel containing 2 µmol NaHS showed uptake of [99mTc]Tc-gluconate, which proved the feasibility as the specific H2S imaging agent in vivo. Temporary ischemic lesion of rat brain showed high radioactivity accumulation representing the feasibility as endogenous H2S imaging agents. CONCLUSION: We proved that 99mTc-labeled α-hydroxy acid especially [99mTc]Tc-gluconate is a novel endogenous H2S imaging agent, which might contribute to study and diagnosis of various diseases related with inflammation and hypoxia.


Assuntos
Gasotransmissores/metabolismo , Sulfeto de Hidrogênio/metabolismo , Hidroxiácidos/química , Compostos de Organotecnécio/química , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Animais , Autorradiografia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Linhagem Celular Tumoral , Humanos , Ratos
13.
Sci Rep ; 9(1): 17026, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745188

RESUMO

We aimed to determine a detailed regional ventricular distribution pattern of the novel cardiac nerve PET radiotracer 18F-LMI1195 in healthy rabbits. Ex-vivo high resolution autoradiographic imaging was conducted to identify accurate ventricular distribution of 18F-LMI1195. In healthy rabbits, 18F-LMI1195 was administered followed by the reference perfusion marker 201Tl for a dual-radiotracer analysis. After 20 min of 18F-LMI1195 distribution time, the rabbits were euthanized, the hearts were extracted, frozen, and cut into 20-µm short axis slices. Subsequently, the short axis sections were exposed to a phosphor imaging plate to determine 18F-LMI1195 distribution (exposure for 3 h). After complete 18F decay, sections were re-exposed to determine 201Tl distribution (exposure for 7 days). For quantitative analysis, segmental regions of Interest (ROIs) were divided into four left ventricular (LV) and a right ventricular (RV) segment on mid-ventricular short axis sections. Subendocardial, mid-portion, and subepicardial ROIs were placed on the LV lateral wall. 18F-LMI1195 distribution was almost homogeneous throughout the LV wall without any significant differences in all four LV ROIs (anterior, posterior, septal and lateral wall, 99 ± 2, 94 ± 5, 94 ± 4 and 97 ± 3%LV, respectively, n.s.). Subepicardial 201Tl uptake was significantly lower compared to the subendocardial portion (subendocardial, mid-portion, and subepicardial activity: 90 ± 3, 96 ± 2 and *80 ± 5%LV, respectively, *p < 0.01 vs. mid-portion). This was in contradistinction to the transmural wall profile of 18F-LMI1195 (90 ± 4, 96 ± 5 and 84 ± 4%LV, n.s.). A slight but significant discrepant transmural radiotracer distribution pattern of 201Tl in comparison to 18F-LMI1195 may be a reflection of physiological sympathetic innervation and perfusion in rabbit hearts.


Assuntos
Radioisótopos de Flúor/farmacocinética , Fluorbenzenos/farmacocinética , Guanidinas/farmacocinética , Ventrículos do Coração/química , Miocárdio/metabolismo , Animais , Autorradiografia/métodos , Ventrículos do Coração/metabolismo , Masculino , Coelhos , Compostos Radiofarmacêuticos/farmacocinética , Sistema Nervoso Simpático/fisiologia
14.
Circ J ; 83(12): 2520-2526, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31619593

RESUMO

BACKGROUND: Methionine uptake after myocardial infarction has been proven to reflect myocardial inflammation. The effect of postconditioning on the post-infarction inflammatory process, however, remains to be elucidated.Methods and Results:In control (n=22) and postconditioning rats (n=23), the left coronary artery was occluded for 30 min, followed by reperfusion for 1, 3, 7, and 14 days. Postconditioning was performed immediately following the reperfusion. 14C-methinine (0.74 MBq) and 201Tl (14.8 MBq) were injected 20 and 10 min prior to sacrifice, respectively. One minute before sacrifice, 150-180 MBq of 99 mTc-MIBI was injected immediately following the re-occlusion of the left coronary artery to verify the area at risk, and left ventricular triple-tracer autoradiography was performed. To examine the ventricular remodeling, echocardiography was performed 2 months after reperfusion in both groups (n=6 each). In the control rats, the methionine uptake ratios on days 1, 3, 7, and 14 were 0.74±0.12, 1.85±0.16, 1.48±0.10, 1.25±0.04, respectively. With postconditioning, methionine uptake was similar on day 3 (1.90±0.21), but was lower on day 7 (1.23±0.22, P<0.05) and day 14 (1.08±0.09, P<0.005). Echocardiography revealed that postconditioning reduced the ventricular end-diastolic (0.97±0.16 to 0.78±0.12 cm, P<0.05) and systolic (0.85±0.21 to 0.55±0.23 cm, P<0.05) dimensions and improved ventricular percentage fractional shortening (12±6.2 to 29±12 %, P=0.01). CONCLUSIONS: 14C-methinine imaging revealed that postconditioning accelerated resolution of inflammation and attenuated ventricular remodeling.


Assuntos
Radioisótopos de Carbono/administração & dosagem , Pós-Condicionamento Isquêmico , Metionina/administração & dosagem , Imagem Molecular , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocardite/prevenção & controle , Compostos Radiofarmacêuticos/administração & dosagem , Animais , Autorradiografia , Modelos Animais de Doenças , Estudos de Viabilidade , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocardite/diagnóstico por imagem , Miocardite/fisiopatologia , Ratos Wistar , Tecnécio Tc 99m Sestamibi/administração & dosagem , Radioisótopos de Tálio/administração & dosagem , Fatores de Tempo , Função Ventricular Esquerda , Remodelação Ventricular
15.
J Cell Mol Med ; 23(12): 8305-8313, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31576678

RESUMO

Triple-negative breast cancer (TNBC) is a highly aggressive tumour that lacks marker for targeted diagnosis. Recently, it was reported that toll-like receptor 5 (TLR5) was associated with some kind of tumours, especially in TNBC, but whether it could be used as a non-invasive monitoring target is not fully understood. Here, we established TLR5- 4T1 cell line with lentivirus-shRNA-TLR5 knock-down transfection (with tag GFP, green fluorescent protein, TLR5- 4T1) and control TLR5+ 4T1 cell line with negative control lentivirus transfection. The effect of TLR5 down-regulation was detected with qPCR and Western blot. 125 I-anti-TLR5 mAb and control isotype 125 I-IgG were prepared and injected to TLR5+/- 4T1-bearing mice models, respectively. Whole-body phosphor-autoradiography, fluorescence imaging and biodistribution were performed. Furthermore, ex vivo tumour TLR5 expression was proved through immunohistochemistry staining. We found that 125 I-anti-TLR5 mAb could bind to TLR5+ 4T1 with high affinity and specificity. Whole-body phosphor-autoradiography after 125 I-anti-TLR5 mAb injection showed TLR5+ 4T1 tumour images in 24 hours, more clearly in 48 hours. Radioactivities in tumour tissues were positively related with TLR5 expression. Biodistribution assay showed that 125 I-anti-TLR5 mAb was mainly metabolized through the liver and kidney, and 125 I-anti-TLR5 mAb was much more accumulated in TLR5+ 4T1 tumour than TLR5- 4T1. In vivo fluorescence imaging successfully showed tumour tissues clearly both in TLR5+ and TLR5- 4T1 mice compared with lentivirus untreated 4T1 tumour. Immunohistochemistry staining showed that TLR5 expression in tumours was indeed down-regulated in TLR5- 4T1 mice. Our results indicated that 125 I-antiTLR5 mAb was an ideal agent for non-invasive imaging of TLR5+ tumours; TLR5 may be as a novel molecular target for TNBC non-invasive diagnosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Radioimunodetecção/métodos , Receptor 5 Toll-Like/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/imunologia , Autorradiografia/métodos , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica/métodos , Radioisótopos do Iodo/metabolismo , Radioisótopos do Iodo/farmacocinética , Masculino , Neoplasias Mamárias Experimentais/diagnóstico , Neoplasias Mamárias Experimentais/genética , Camundongos Nus , Interferência de RNA , Coloração e Rotulagem/métodos , Distribuição Tecidual , Receptor 5 Toll-Like/genética , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/genética
16.
Microsc Microanal ; 25(6): 1331-1340, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31648656

RESUMO

Our group has reported the imprint formation of biological material on polycarbonate nuclear track detectors by UV-C exposure, which is used as an approach to simultaneously visualize cell imprints and nuclear tracks coming from the boron neutron capture reaction. Considering that the cell nucleus has a higher UV-C absorption than the cytoplasm and that hematoxylin preferentially stains the nucleus, we proposed to enhance the contrast between these two main cell structures by hematoxylin staining before UV-C sensitization. In this study, several experiments were performed in order to optimize UV-C exposure parameters and chemical etching conditions for cell imprint formation using the SK-BR-3 breast cancer cell line. The proposed method improves significantly the resolution of the cell imprints. It allows clear differentiation of the nucleus from the rest of the cell, together with nuclear tracks pits. Moreover, it reduces considerably the UV-C exposure time, an important experimental issue. The proposed methodology can be applied to study the boron distribution independently from the chosen cell line and/or boron compounds.


Assuntos
Autorradiografia/métodos , Análise de Ativação de Nêutrons/métodos , Coloração e Rotulagem/métodos , Raios Ultravioleta , Boro/efeitos da radiação , Linhagem Celular Tumoral , Hematoxilina/metabolismo , Humanos , Oligoelementos/efeitos da radiação
17.
Sci Rep ; 9(1): 13672, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31541162

RESUMO

It is well settled that the amyloidogenic properties of the plasma protein transporter transthyretin (TTR) can be modulated by compounds that stabilize its native tetrameric conformation. TTR is also present in cerebrospinal fluid where it can bind to Aß-peptides and prevent Aß aggregation. We have previously shown that treatment of Alzheimer's Disease (AD) model mice with iododiflunisal (IDIF), a TTR tetramer stabilizing compound, prevents AD pathologies. This evidence positioned IDIF as a new lead drug for AD. In dissecting the mechanism of action of IDIF, we disclose here different labeling strategies for the preparation of 131I-labeled IDIF and 131I- and 124I-labeled TTR, which have been further used for the preparation of IDIF-TTR complexes labeled either on the compound or the protein. The biodistribution of all labeled species after intravenous administration has been investigated in mice using ex vivo and in vivo techniques. Our results confirm the capacity of TTR to cross the blood brain barrier (BBB) and suggest that the formation of TTR-IDIF complexes enhances BBB permeability of both IDIF and TTR. The increased TTR and IDIF brain concentrations may result in higher Aß-peptide sequestration capacity with the subsequent inhibition of AD symptoms as we have previously observed in mice.


Assuntos
Encéfalo/diagnóstico por imagem , Diflunisal/análogos & derivados , Radioisótopos do Iodo/química , Pré-Albumina/química , Pré-Albumina/farmacocinética , Administração Intravenosa , Peptídeos beta-Amiloides/metabolismo , Animais , Autorradiografia , Barreira Hematoencefálica/química , Encéfalo/metabolismo , Diflunisal/administração & dosagem , Diflunisal/química , Diflunisal/farmacocinética , Camundongos , Tomografia por Emissão de Pósitrons , Pré-Albumina/administração & dosagem , Distribuição Tecidual
18.
Pharmacol Rep ; 71(6): 994-1000, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546158

RESUMO

BACKGROUND: There is a strong support for the role of serotonin (5-HT) neurotransmission in depression and in the mechanism of action of antidepressants. Among 5-HT receptors, 5-HT2A receptor subtype seems to be an important target implicated in the above disorder. METHODS: The aim of the study was to investigate the effects of antidepressants, such as imipramine (15 mg/kg), escitalopram (10 mg/kg) and tianeptine (10 mg/kg) as well as drugs with antidepressant activity, including N-acetylcysteine (100 mg/kg) and URB597 (a fatty acid amide hydrolase inhibitor, 0.3 mg/kg) on the 5-HT2A receptor labeling pattern in selected rat brain regions. Following acute or chronic (14 days) drug administration, rat brains were analyzed by using autoradiography with the 5-HT2A receptor antagonist [3H]ketanserin. RESULTS: Single dose or chronic administration of imipramine decreased the radioligand binding in the claustrum and cortical subregions. The [3H]ketanserin binding either increased or decreased in cortical areas after acute N-acetylcysteine and URB597 administration, respectively. A similar shift towards reduction of the [3H]ketanserin binding was detected in the nucleus accumbens shell following either acute treatment with imipramine, escitalopram, N-acetylcysteine and URB597 or repeated administration of imipramine, tianeptine and URB597. CONCLUSIONS: In conclusion, the present result indicate different sensitivity of brain 5-HT2A receptors to antidepressant drugs depending on schedule of drug administration and rat brain regions. The decrease of accumbal shell 5-HT2A receptor labeling by antidepressant drugs exhibiting different primary mechanism of action seems to be a common targeting mechanism associated with the outcome of depression treatment.


Assuntos
Antidepressivos/farmacologia , Núcleo Accumbens/metabolismo , Receptor 5-HT2A de Serotonina/metabolismo , Acetilcisteína/farmacologia , Animais , Autorradiografia , Benzamidas/farmacologia , Encéfalo/metabolismo , Carbamatos/farmacologia , Citalopram/farmacologia , Imipramina/farmacologia , Ketanserina , Masculino , Ratos , Ratos Wistar , Tiazepinas/farmacologia
19.
Brain Struct Funct ; 224(8): 2733-2756, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31392403

RESUMO

The macaque monkey superior parietal lobule (SPL) is part of a neuronal network involved in the integration of information from visual and somatosensory cortical areas for execution of reaching and grasping movements. We applied quantitative in vitro receptor autoradiography to analyse the distribution patterns of 15 different receptors for glutamate, GABA, acetylcholine, serotonin, dopamine, and adenosine in the SPL of three adult male Macaca fascicularis monkeys. For each area, mean (averaged over all cortical layers) receptor densities were visualized as a receptor fingerprint of that area. Multivariate analyses were conducted to detect clusters of areas according to the degree of (dis)similarity of their receptor organization. Differences in regional and laminar receptor distributions confirm the location and extent of areas V6, V6Av, V6Ad, PEc, PEci, and PGm as found in cytoarchitectonic and functional studies, but also enable the definition of three subdivisions within area PE. Receptor densities are higher in supra- than in infragranular layers, with the exception of kainate, M2, and adenosine receptors. Glutamate and GABAergic receptors are the most expressed in all areas analysed. Hierarchical cluster analyses demonstrate that SPL areas are organized in two groups, an organization that corresponds to the visual or sensory-motor characteristics of those areas. Finally, based on present results and in the framework of our current understanding of the structural and functional organization of the primate SPL, we propose a novel pattern of homologies between human and macaque SPL areas.


Assuntos
Neurônios/citologia , Neurônios/metabolismo , Lobo Parietal/citologia , Lobo Parietal/metabolismo , Receptores de Neurotransmissores/metabolismo , Animais , Autorradiografia , Macaca fascicularis , Masculino , Receptores Colinérgicos/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores de GABA/metabolismo , Receptores de Glutamato/metabolismo , Receptores Purinérgicos P1/metabolismo , Receptores de Serotonina/metabolismo
20.
Behav Brain Res ; 375: 112116, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31377254

RESUMO

Studies of brain functional activation during spatial navigation using electrophysiology and immediate-early gene responses have typically targeted a limited number of brain regions. Our study provides the first whole brain analysis of cerebral activation during retrieval of spatial memory in the freely-moving rat. Rats (LEARNERS) were trained in the Barnes maze, an allocentric spatial navigation task, while CONTROLS received passive exposure. After 19 days, functional brain mapping was performed during recall by bolus intravenous injection of [14C]-iodoantipyrine using a novel subcutaneous minipump triggered by remote activation. Regional cerebral blood flow (rCBF)-related tissue radioactivity was analyzed by statistical parametric mapping from autoradiographic images of the three-dimensionally reconstructed brains. Functional connectivity was examined between regions of the spatial navigation circuit through interregional correlation analysis. Significant rCBF increases were noted in LEARNERS compared to CONTROLS broadly across the spatial navigation circuit, including the hippocampus (anterior dorsal CA1, posterior ventral CA1-3), subiculum, thalamus, striatum, medial septum, cerebral cortex, with decreases noted in the mammillary nucleus, amygdala and insula. LEARNERS showed a significantly greater positive correlation of rCBF of the ventral hippocampus with retrosplenial, lateral orbital, parietal and primary visual cortex, and a significantly more negative correlation with the mammillary nucleus, amygdala, posterior entorhinal cortex, and anterior thalamic nucleus. The complex sensory component of the spatial navigation task was underscored by broad activation across visual, somatosensory, olfactory, auditory and vestibular circuits which was enhanced in LEARNERS. Brain mapping facilitated by an implantable minipump represents a powerful tool for evaluation of mammalian behaviors dependent on locomotion.


Assuntos
Mapeamento Encefálico/métodos , Circulação Cerebrovascular/fisiologia , Memória Espacial/fisiologia , Animais , Antipirina/análogos & derivados , Antipirina/farmacologia , Autorradiografia , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Aprendizagem em Labirinto , Rememoração Mental , Ratos , Ratos Sprague-Dawley , Memória Espacial/efeitos dos fármacos
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