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1.
Cell Mol Biol Lett ; 29(1): 105, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030477

RESUMO

BACKGROUND: The organism-wide effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral infection are well studied, but little is known about the dynamics of how the infection spreads in time among or within cells due to the scarcity of suitable high-resolution experimental systems. It has been reported that SARS-CoV-2 infection pathways converge at calcium influx and subcellular calcium distribution changes. Imaging combined with a proper staining technique is an effective tool for studying subcellular calcium-related infection and replication mechanisms at such resolutions. METHODS: Using two-photon (2P) fluorescence imaging with our novel Ca-selective dye, automated image analysis and clustering analysis were applied to reveal titer and variant effects on SARS-CoV-2-infected Vero E6 cells. RESULTS: The application of a new calcium sensor molecule is shown, combined with a high-end 2P technique for imaging and identifying the patterns associated with cellular infection damage within cells. Vero E6 cells infected with SARS-CoV-2 variants, D614G or B.1.1.7, exhibit elevated cytosolic calcium levels, allowing infection monitoring by tracking the cellular changes in calcium level by the internalized calcium sensor. The imaging provides valuable information on how the level and intracellular distribution of calcium are perturbed during the infection. Moreover, two-photon calcium sensing allowed the distinction of infections by two studied viral variants via cluster analysis of the image parameters. This approach will facilitate the study of cellular correlates of infection and their quantification depending on viral variants and viral load. CONCLUSIONS: We propose a new two-photon microscopy-based method combined with a cell-internalized sensor to quantify the level of SARS-CoV-2 infection. We optimized the applied dye concentrations to not interfere with viral fusion and viral replication events. The presented method ensured the proper monitoring of viral infection, replication, and cell fate. It also enabled distinguishing intracellular details of cell damage, such as vacuole and apoptotic body formation. Using clustering analysis, 2P microscopy calcium fluorescence images were suitable to distinguish two different viral variants in cell cultures. Cellular harm levels read out by calcium imaging were quantitatively related to the initial viral multiplicity of infection numbers. Thus, 2P quantitative calcium imaging might be used as a correlate of infection or a correlate of activity in cellular antiviral studies.


Assuntos
COVID-19 , Cálcio , Corantes Fluorescentes , SARS-CoV-2 , Chlorocebus aethiops , Células Vero , Cálcio/metabolismo , Cálcio/análise , Animais , COVID-19/virologia , COVID-19/metabolismo , Corantes Fluorescentes/química , Humanos , Fótons
2.
Int J Mol Sci ; 24(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38069441

RESUMO

Following the in vivo biodistribution of platelets can contribute to a better understanding of their physiological and pathological roles, and nuclear imaging methods, such as single photon emission tomography (SPECT), provide an excellent method for that. SPECT imaging needs stable labeling of the platelets with a radioisotope. In this study, we report a new method to label platelets with 99mTc, the most frequently used isotope for SPECT in clinical applications. The proposed radiolabeling procedure uses a membrane-binding peptide, duramycin. Our results show that duramycin does not cause significant platelet activation, and radiolabeling can be carried out with a procedure utilizing a simple labeling step followed by a size-exclusion chromatography-based purification step. The in vivo application of the radiolabeled human platelets in mice yielded quantitative biodistribution images of the spleen and liver and no accumulation in the lungs. The performed small-animal SPECT/CT in vivo imaging investigations revealed good in vivo stability of the labeling, which paves the way for further applications of 99mTc-labeled-Duramycin in platelet imaging.


Assuntos
Bacteriocinas , Tomografia Computadorizada de Emissão de Fóton Único , Camundongos , Humanos , Animais , Distribuição Tecidual , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Peptídeos/metabolismo , Bacteriocinas/metabolismo
3.
Int J Mol Sci ; 24(22)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-38003394

RESUMO

The need for stable and well-defined magnetic nanoparticles is constantly increasing in biomedical applications; however, their preparation remains challenging. We used two different solvothermal methods (12 h reflux and a 4 min microwave, MW) to synthesize amine-functionalized zinc ferrite (ZnFe2O4-NH2) superparamagnetic nanoparticles. The morphological features of the two ferrite samples were the same, but the average particle size was slightly larger in the case of MW activation: 47 ± 14 nm (Refl.) vs. 63 ± 20 nm (MW). Phase identification measurements confirmed the exclusive presence of zinc ferrite with virtually the same magnetic properties. The Refl. samples had a zeta potential of -23.8 ± 4.4 mV, in contrast to the +7.6 ± 6.8 mV measured for the MW sample. To overcome stability problems in the colloidal phase, the ferrite nanoparticles were embedded in polyvinylpyrrolidone and could be easily redispersed in water. Two PVP-coated zinc ferrite samples were administered (1 mg/mL ZnFe2O4) in X BalbC mice and were compared as contrast agents in magnetic resonance imaging (MRI). After determining the r1/r2 ratio, the samples were compared to other commercially available contrast agents. Consistent with other SPION nanoparticles, our sample exhibits a concentrated presence in the hepatic region of the animals, with comparable biodistribution and pharmacokinetics suspected. Moreover, a small dose of 1.3 mg/body weight kg was found to be sufficient for effective imaging. It should also be noted that no toxic side effects were observed, making ZnFe2O4-NH2 advantageous for pharmaceutical formulations.


Assuntos
Meios de Contraste , Nanopartículas , Camundongos , Animais , Polímeros , Aminas , Zinco , Distribuição Tecidual , Imageamento por Ressonância Magnética/métodos , Compostos Férricos , Preparações Farmacêuticas
4.
Cell Mol Life Sci ; 78(23): 7589-7604, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34665280

RESUMO

Liver plays a central role in elimination of circulating extracellular vesicles (EVs), and it also significantly contributes to EV release. However, the involvement of the different liver cell populations remains unknown. Here, we investigated EV uptake and release both in normolipemia and hyperlipidemia. C57BL/6 mice were kept on high fat diet for 20-30 weeks before circulating EV profiles were determined. In addition, control mice were intravenously injected with 99mTc-HYNIC-Duramycin labeled EVs, and an hour later, biodistribution was analyzed by SPECT/CT. In vitro, isolated liver cell types were tested for EV release and uptake with/without prior fatty acid treatment. We detected an elevated circulating EV number after the high fat diet. To clarify the differential involvement of liver cell types, we carried out in vitro experiments. We found an increased release of EVs by primary hepatocytes at concentrations of fatty acids comparable to what is characteristic for hyperlipidemia. When investigating EV biodistribution with 99mTc-labeled EVs, we detected EV accumulation primarily in the liver upon intravenous injection of mice with medium (326.3 ± 19.8 nm) and small EVs (130.5 ± 5.8 nm). In vitro, we found that medium and small EVs were preferentially taken up by Kupffer cells, and liver sinusoidal endothelial cells, respectively. Finally, we demonstrated that in hyperlipidemia, there was a decreased EV uptake both by Kupffer cells and liver sinusoidal endothelial cells. Our data suggest that hyperlipidema increases the release and reduces the uptake of EVs by liver cells. We also provide evidence for a size-dependent differential EV uptake by the different cell types of the liver. The EV radiolabeling protocol using 99mTc-Duramycin may provide a fast and simple labeling approach for SPECT/CT imaging of EVs biodistribution.


Assuntos
Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Hepatócitos/metabolismo , Hiperlipidemias/fisiopatologia , Fígado/metabolismo , Animais , Dieta Hiperlipídica , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36232467

RESUMO

Nutritional interventions may highly contribute to the maintenance or restoration of human health. Grapes (Vitis vinifera) are one of the oldest known beneficial nutritional components of the human diet. Their high polyphenol content has been proven to enhance human health beyond doubt in statistics-based public health studies, especially in the prevention of cardiovascular disease and cancer. The current review concentrates on presenting and classifying polyphenol bioactive molecules (resveratrol, quercetin, catechin/epicatechin, etc.) available in high quantities in Vitis vinifera grapes or their byproducts. The molecular pathways and cellular signaling cascades involved in the effects of these polyphenol molecules are also presented in this review, which summarizes currently available in vitro and in vivo experimental literature data on their biological activities mostly in easily accessible tabular form. New molecules for different therapeutic purposes can also be synthesized based on existing polyphenol compound classes available in high quantities in grape, wine, and grape marc. Therefore an overview of these molecular structures is provided. Novel possibilities as dendrimer nanobioconjugates are reviewed, too. Currently available in vitro and in vivo experimental literature data on polyphenol biological activities are presented in easily accessible tabular form. The scope of the review details the antidiabetic, anticarcinogenic, antiviral, vasoprotective, and neuroprotective roles of grape-origin flavonoids. The novelty of the study lies in the description of the processing of agricultural by-products (grape seeds and skins) of industrial relevance, and the detailed description of the molecular mechanisms of action. In addition, the review of the clinical therapeutic applications of polyphenols is unique as no summary study has yet been done.


Assuntos
Catequina , Dendrímeros , Vitis , Antioxidantes/farmacologia , Antivirais/análise , Flavonoides/farmacologia , Humanos , Hipoglicemiantes/análise , Polifenóis/análise , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Quercetina/análise , Resveratrol , Sementes/química , Vitis/química
6.
Int J Mol Sci ; 22(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922728

RESUMO

Bc-DLFL.1 is a novel spontaneous, high-grade transplantable mouse B-cell lymphoma model for selective serosal propagation. These cells attach to the omentum and mesentery and show dissemination in mesenteric lymph nodes. We aimed to investigate its early stage spread at one day post-intraperitoneal inoculation of lymphoma cells (n = 18 mice), and its advanced stage at seven days post-inoculation with in vivo [18F]FDG-PET and [18F]PET/MRI, and ex vivo by autoradiography and Cherenkov luminescence imaging (CLI). Of the early stage group, nine animals received intraperitoneal injections, and nine received intravenous [18F]FDG injections. The advanced stage group (n = 3) received intravenous FDG injections. In the early stage, using autoradiography we observed a marked accumulation in the mesentery after intraperitoneal FDG injection. Using other imaging methods and autoradiography, following the intravenous injection of FDG no accumulations were detected. At the advanced stage, tracer accumulation was clearly detected in mesenteric lymph nodes and in the peritoneum after intravenous administration using PET. We confirmed the results with immunohistochemistry. Our results in this model highlight the importance of local FDG administration during diagnostic imaging to precisely assess early peritoneal manifestations of other malignancies (colon, stomach, ovary). These findings also support the importance of applying topical therapies, in addition to systemic treatments in peritoneal cancer spread.


Assuntos
Modelos Animais de Doenças , Glucose/metabolismo , Linfoma/patologia , Imagem Multimodal/métodos , Animais , Fluordesoxiglucose F18/metabolismo , Injeções Intraperitoneais , Metástase Linfática , Linfoma/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos BALB C , Micrometástase de Neoplasia , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/metabolismo , Tomografia Computadorizada por Raios X/métodos
7.
Int J Mol Sci ; 22(19)2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34638688

RESUMO

This paper focuses on preliminary in vitro and in vivo testing of new bivalent folate-targeted PEGylated doxorubicin (DOX) made by modular chemo-enzymatic processes (FA2-dPEG-DOX2). A unique feature is the use of monodisperse PEG (dPEG). The modular approach with enzyme catalysis ensures exclusive γ-conjugation of folic acid, full conversion and selectivity, and no metal catalyst residues. Flow cytometry analysis showed that at 10 µM concentration, both free DOX and FA2-dPEG-DOX2 would be taken up by 99.9% of triple-negative breast cancer cells in 2 h. Intratumoral injection to mice seemed to delay tumor growth more than intravenous delivery. The mouse health status, food, water consumption, and behavior remained unchanged during the observation.


Assuntos
Doxorrubicina , Ácido Fólico , Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Feminino , Citometria de Fluxo , Ácido Fólico/química , Ácido Fólico/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Chemistry ; 26(9): 1989-2001, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31755596

RESUMO

Bifunctional chelators as parts of modular metal-based radiopharmaceuticals are responsible for stable complexation of the radiometal ion and for covalent linkage between the complex and the targeting vector. To avoid loss of complex stability, the bioconjugation strategy should not interfere with the radiometal chelation by occupying coordinating groups. The C9 position of the very stable CuII chelator 3,7-diazabicyclo[3.3.1]nonane (bispidine) is virtually predestined to introduce functional groups for facile bioconjugation as this functionalisation does not disturb the metal binding centre. We describe the preparation and characterisation of a set of novel bispidine derivatives equipped with suitable functional groups for diverse bioconjugation reactions, including common amine coupling strategies (bispidine-isothiocyanate) and the Cu-free strain-promoted alkyne-azide cycloaddition. We demonstrate their functionality and versatility in an exemplary way by conjugation to an antibody-based biomolecule and validate the obtained conjugate in vitro and in vivo.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Quelantes/química , Cobre/química , Compostos Radiofarmacêuticos/química , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Linhagem Celular Tumoral , Cetuximab/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Reação de Cicloadição , Humanos , Camundongos , Microscopia de Fluorescência , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/síntese química , Transplante Heterólogo
9.
Int J Mol Sci ; 21(17)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867390

RESUMO

There is an increasing number of studies showing that thrombocytosis-accompanying a variety of solid tumors including colorectal cancer (CRC)-is associated with shorter survival and earlier development of metastases. The mechanisms of cancer-associated thrombocytosis are not completely understood yet. The aim of our study was to evaluate the role of IL-6 in tumor development and thrombocytosis in mice with inflammation-induced CRC, using a CRISPR/cas9 IL-6 knockout (KO) strain. Adult male FB/Ant mice (n = 39) were divided into four groups: (1) IL-6 KO controls (n = 5); (2) IL-6 KO CRC model group (n = 18); (3) Wild-type (WT) controls (n = 6); and (4) WT CRC model group (n = 10). CRC model animals in (2) and (4) received azoxymethane (AOM)/dextran sodium sulfate (DSS) treatment to induce inflammation-related CRC. Plasma and liver tissues were obtained to determine platelet counts, IL-6 and thrombopoietin-1 (TPO) levels. In 1 WT and 2 IL-6 KO mice in vivo confocal endomicroscopy and 18F-fluorodeoxyglucose (FDG) PET/MRI examinations were performed to evaluate the inflammatory burden and neoplastic transformation. At the end of the study, tumorous foci could be observed macroscopically in both CRC model groups. Platelet counts were significantly elevated in the WT CRC group compared to the IL-6 KO CRC group. TPO levels moved parallelly with platelet counts. In vivo fluorescent microscopy showed signs of disordered and multi-nuclear crypt morphology with increased mucus production in a WT animal, while regular mucosal structure was prominent in the IL-6 KO animals. The WT animal presented more intense and larger colonic FDG uptake than IL-6 KO animals. Our study confirmed thrombocytosis accompanying inflammation-related CRC and the crucial role of IL-6 in this process. Significantly higher platelet counts were found in the WT CRC group compared to both the control group and the IL-6 KO group. Concomitantly, the tumor burden of WT mice was also greater than that of IL-6 KO mice. Our findings are in line with earlier paraneoplastic IL-6 effect suggestions.


Assuntos
Neoplasias Associadas a Colite/genética , Interleucina-6/genética , Trombocitose/genética , Animais , Azoximetano/efeitos adversos , Neoplasias Associadas a Colite/induzido quimicamente , Neoplasias Associadas a Colite/complicações , Neoplasias Associadas a Colite/diagnóstico por imagem , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Imageamento por Ressonância Magnética , Masculino , Camundongos , Contagem de Plaquetas , Tomografia por Emissão de Pósitrons , Trombocitose/sangue , Trombocitose/etiologia , Trombocitose/metabolismo , Trombopoetina/metabolismo
10.
Am J Physiol Heart Circ Physiol ; 311(4): H927-H943, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27521417

RESUMO

Although incidence and prevalence of prediabetes are increasing, little is known about its cardiac effects. Therefore, our aim was to investigate the effect of prediabetes on cardiac function and to characterize parameters and pathways associated with deteriorated cardiac performance. Long-Evans rats were fed with either control or high-fat chow for 21 wk and treated with a single low dose (20 mg/kg) of streptozotocin at week 4 High-fat and streptozotocin treatment induced prediabetes as characterized by slightly elevated fasting blood glucose, impaired glucose and insulin tolerance, increased visceral adipose tissue and plasma leptin levels, as well as sensory neuropathy. In prediabetic animals, a mild diastolic dysfunction was observed, the number of myocardial lipid droplets increased, and left ventricular mass and wall thickness were elevated; however, no molecular sign of fibrosis or cardiac hypertrophy was shown. In prediabetes, production of reactive oxygen species was elevated in subsarcolemmal mitochondria. Expression of mitofusin-2 was increased, while the phosphorylation of phospholamban and expression of Bcl-2/adenovirus E1B 19-kDa protein-interacting protein 3 (BNIP3, a marker of mitophagy) decreased. However, expression of other markers of cardiac auto- and mitophagy, mitochondrial dynamics, inflammation, heat shock proteins, Ca2+/calmodulin-dependent protein kinase II, mammalian target of rapamycin, or apoptotic pathways were unchanged in prediabetes. This is the first comprehensive analysis of cardiac effects of prediabetes indicating that mild diastolic dysfunction and cardiac hypertrophy are multifactorial phenomena that are associated with early changes in mitophagy, cardiac lipid accumulation, and elevated oxidative stress and that prediabetes-induced oxidative stress originates from the subsarcolemmal mitochondria.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Hipertrofia Ventricular Esquerda/metabolismo , Mitocôndrias Cardíacas/metabolismo , Estresse Oxidativo , Estado Pré-Diabético/metabolismo , Disfunção Ventricular Esquerda/metabolismo , Adipocinas/metabolismo , Tecido Adiposo , Animais , Apoptose , Autofagia , Composição Corporal , Proteínas de Ligação ao Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas , Diástole , Dieta Hiperlipídica , Ecocardiografia , GTP Fosfo-Hidrolases , Proteínas de Choque Térmico/metabolismo , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Mitocôndrias Cardíacas/ultraestrutura , Proteínas Mitocondriais/metabolismo , Mitofagia , Miocárdio/metabolismo , Miocárdio/ultraestrutura , Fosforilação , Estado Pré-Diabético/fisiopatologia , Ratos , Ratos Long-Evans , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Sarcolema , Serina-Treonina Quinases TOR/metabolismo , Disfunção Ventricular Esquerda/fisiopatologia , Pressão Ventricular
11.
Bioconjug Chem ; 27(2): 319-28, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26172432

RESUMO

Multimodal nanoparticulate materials are described, offering magnetic, radionuclide, and fluorescent imaging capabilities to exploit the complementary advantages of magnetic resonance imaging (MRI), positron emission tomography/single-photon emission commuted tomography (PET/SPECT), and optical imaging. They comprise Fe3O4@NaYF4 core/shell nanoparticles (NPs) with different cation dopants in the shell or core, including Co0.16Fe2.84O4@NaYF4(Yb, Er) and Fe3O4@NaYF4(Yb, Tm). These NPs are stabilized by bisphosphonate polyethylene glycol conjugates (BP-PEG), and then show a high transverse relaxivity (r2) up to 326 mM(-1) s(-1) at 3T, a high affinity to [(18)F]-fluoride or radiometal-bisphosphonate conjugates (e.g., (64)Cu and (99m)Tc), and fluorescent emissions from 500 to 800 nm under excitation at 980 nm. The biodistribution of intravenously administered particles determined by PET/MR imaging suggests that negatively charged Co0.16Fe2.84O4@NaYF4(Yb, Er)-BP-PEG (10K) NPs cleared from the blood pool more slowly than positively charged NPs Fe3O4@NaYF4(Yb, Tm)-BP-PEG (2K). Preliminary results in sentinel lymph node imaging in mice indicate the advantages of multimodal imaging.


Assuntos
Óxido Ferroso-Férrico/química , Fluoretos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Imagem Óptica/métodos , Tomografia por Emissão de Pósitrons/métodos , Ítrio/química , Animais , Difosfonatos/química , Difosfonatos/farmacocinética , Óxido Ferroso-Férrico/farmacocinética , Fluoretos/farmacocinética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Nus , Imagem Multimodal/métodos , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Ítrio/farmacocinética
12.
BMC Med Imaging ; 16: 14, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26864653

RESUMO

BACKGROUND: Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. METHODS: To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann-Whitney post hoc (MWph) tests were used. RESULTS: Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. CONCLUSIONS: A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Interpretação de Imagem Assistida por Computador/métodos , Pneumopatias/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Animais , Modelos Animais de Doenças , Feminino , Fractais , Humanos , Pneumopatias/induzido quimicamente , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Normal
13.
ACS Omega ; 9(42): 42808-42813, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39464435

RESUMO

Introduction: Bacterial outer membrane vesicles (OMVs) are emerging as important players in the host-microbiome interaction, while also proving to be a promising platform for vaccine development and targeted drug delivery. The available methods for measuring their biodistribution, however, are limited. We aimed to establish a high-efficiency radiolabeling method for the treatment of OMVs. Methods: 99mTc-HYNIC-duramycin was incubated with OMVs isolated from E. coli BL21(DE3) ΔnlpI ΔlpxM. Radiolabeling efficiency (RLE) and radiochemical purity (RCP) were measured with size-exclusion high-performance liquid chromatography. The biodistribution was quantitatively measured in mice using SPECT/CT imaging. Results: RLE was 81.84 ± 2.03% for undiluted OMV suspension and 56.17 ± 2.29% for 100× dilution. Postlabeling purification with a spin-desalting column results in 100% radioactivity in the OMV fraction according to HPLC, indicating 100% RCP of the final product. The biodistribution was found to be in line with previous data reported in the literature using other OMV tracking attempts. Conclusions: Our findings illustrate that using HYNIC-duramycin for labeling of the OMVs enhances efficiency and is easily implementable for in vivo imaging studies, significantly improving upon earlier methods.

15.
Geroscience ; 45(4): 2179-2193, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36879183

RESUMO

Ivermectin, an antiparasitic drug, has been repurposed for COVID-19 treatment during the SARS-CoV-2 pandemic. Although its antiviral efficacy was confirmed early in vitro and in preclinical studies, its clinical efficacy remained ambiguous. Our purpose was to assess the efficacy of ivermectin in terms of time to viral clearance based on the meta-analysis of available clinical trials at the closing date of the data search period, one year after the start of the pandemic. This meta-analysis was reported by following the PRISMA guidelines and by using the PICO format for formulating the question. The study protocol was registered on PROSPERO. Embase, MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), bioRvix, and medRvix were searched for human studies of patients receiving ivermectin therapy with control groups. No language or publication status restrictions were applied. The search ended on 1/31/2021 exactly one year after WHO declared the public health emergency on novel coronavirus. The meta-analysis of three trials involving 382 patients revealed that the mean time to viral clearance was 5.74 days shorter in case of ivermectin treatment compared to the control groups [WMD = -5.74, 95% CI (-11.1, -0.39), p = 0.036]. Ivermectin has significantly reduced the time to viral clearance in mild to moderate COVID-19 diseases compared to control groups. However, more eligible studies are needed for analysis to increase the quality of evidence of ivermectin use in COVID-19.


Assuntos
COVID-19 , Humanos , Ivermectina/uso terapêutico , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Resultado do Tratamento
16.
Int J Nanomedicine ; 18: 2071-2086, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113796

RESUMO

Introduction: One of the major challenges in the clinical translation of nanoparticles is the development of formulations combining favorable efficacy and optimal safety. In the past, iron oxide nanoparticles have been introduced as an alternative for gadolinium-containing contrast agents; however, candidates available at the time were not free from adverse effects. Methods: Following the development of a potent iron oxide-based contrast agent SPIONDex, we now performed a systematic comparison of this formulation with the conventional contrast agent ferucarbotran and with ferumoxytol, taking into consideration their physicochemical characteristics, bio- and hemocompatibility in vitro and in vivo, as well as their liver imaging properties in rats. Results: The results demonstrated superior in vitro cyto-, hemo- and immunocompatibility of SPIONDex in comparison to the other two formulations. Intravenous administration of ferucarbotran or ferumoxytol induced strong complement activation-related pseudoallergy in pigs. In contrast, SPIONDex did not elicit any hypersensitivity reactions in the experimental animals. In a rat model, comparable liver imaging properties, but a faster clearance was demonstrated for SPIONDex. Conclusion: The results indicate that SPIONDex possess an exceptional safety compared to the other two formulations, making them a promising candidate for further clinical translation.


Assuntos
Meios de Contraste , Nanopartículas de Magnetita , Ratos , Animais , Suínos , Óxido Ferroso-Férrico , Segurança do Paciente , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/toxicidade
17.
Sci Rep ; 13(1): 18752, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907509

RESUMO

The important roles of bacterial outer membrane vesicles (OMVs) in various diseases and their emergence as a promising platform for vaccine development and targeted drug delivery necessitates the development of imaging techniques suitable for quantifying their biodistribution with high precision. To address this requirement, we aimed to develop an OMV specific radiolabeling technique for positron emission tomography (PET). A novel bacterial strain (E. coli BL21(DE3) ΔnlpI, ΔlpxM) was created for efficient OMV production, and OMVs were characterized using various methods. SpyCatcher was anchored to the OMV outer membrane using autotransporter-based surface display systems. Synthetic SpyTag-NODAGA conjugates were tested for OMV surface binding and 64Cu labeling efficiency. The final labeling protocol shows a radiochemical purity of 100% with a ~ 29% radiolabeling efficiency and excellent serum stability. The in vivo biodistribution of OMVs labeled with 64Cu was determined in mice using PET/MRI imaging which revealed that the biodistribution of radiolabeled OMVs in mice is characteristic of previously reported data with the highest organ uptakes corresponding to the liver and spleen 3, 6, and 12 h following intravenous administration. This novel method can serve as a basis for a general OMV radiolabeling scheme and could be used in vaccine- and drug-carrier development based on bioengineered OMVs.


Assuntos
Escherichia coli , Vesículas Extracelulares , Animais , Camundongos , Escherichia coli/metabolismo , Membrana Externa Bacteriana/metabolismo , Distribuição Tecidual , Vesículas Extracelulares/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Imagem Molecular
18.
Front Immunol ; 14: 1204543, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37383226

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) led to millions of infections and deaths worldwide. As this virus evolves rapidly, there is a high need for treatment options that can win the race against new emerging variants of concern. Here, we describe a novel immunotherapeutic drug based on the SARS-CoV-2 entry receptor ACE2 and provide experimental evidence that it cannot only be used for (i) neutralization of SARS-CoV-2 in vitro and in SARS-CoV-2-infected animal models but also for (ii) clearance of virus-infected cells. For the latter purpose, we equipped the ACE2 decoy with an epitope tag. Thereby, we converted it to an adapter molecule, which we successfully applied in the modular platforms UniMAB and UniCAR for retargeting of either unmodified or universal chimeric antigen receptor-modified immune effector cells. Our results pave the way for a clinical application of this novel ACE2 decoy, which will clearly improve COVID-19 treatment.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Humanos , Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19
19.
Sci Rep ; 12(1): 19441, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376345

RESUMO

Aiming to improve the postoperative outcome of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), the effect of physical prehabilitation (PP) was investigated in experimental model. Male Wistar rats (n = 106) divided to PP and sedentary (S) groups underwent ALPPS. Changes in liver weight, Ki67 index and liver volume by magnetic resonance imaging (MRI) were evaluated. Liver function was assessed by laboratory parameters and 99mTc-mebrofenin single-photon emission computed tomography (SPECT) hepatobiliary scintigraphy (HBS). Utilizing endotoxemia model mortality and septic parameters were investigated. Liver mass (p < 0.001), Ki67 index (p < 0.001) and MRI liver volume (p < 0.05) increased in the PP group compared to the S group. Both standard laboratory parameters (p < 0.001) and HBS (p < 0.05) showed enhanced liver function in the PP group compared to the S group. The vulnerability of animals improved in the PP group, as mortality decreased (p < 0.001), while septic laboratory parameters improved (p < 0.05) compared to the S group in the endotoxemia model. Our study demonstrated for the first time the beneficial role of PP on not only volumetric but also functional liver regeneration and postoperative vulnerability after ALLPS.


Assuntos
Endotoxemia , Neoplasias Hepáticas , Humanos , Ratos , Animais , Masculino , Hepatectomia/métodos , Veia Porta/cirurgia , Antígeno Ki-67 , Exercício Pré-Operatório , Resultado do Tratamento , Ratos Wistar , Fígado/cirurgia , Regeneração Hepática , Ligadura , Modelos Teóricos
20.
Front Nucl Med ; 2: 870910, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-39354958

RESUMO

Bisphosponates are an interesting molecular class and in recent years their application has found its way into radiopharmaceutical research and thus into molecular imaging. In addition to great imaging of bone metastases, bisphospnate-based tracers for imaging also have some significant drawbacks. For example, their synthesis is often difficult. Additionally, this can lead to complex and almost impossible purification and quality control. This has limited the production and labeling of suitable molecular and their widespread use to a few facilities. Our squaric acid-based approach provides a way to overcome these problems and makes the synthesis as well as the purification of the compounds much easier. In addition, we were able to demonstrate that labeling with 68Ga is possible under the typical conditions.

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