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1.
Int J Mol Sci ; 24(23)2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38069441

RESUMEN

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.


Asunto(s)
Bacteriocinas , Tomografía Computarizada de Emisión de Fotón Único , Ratones , Humanos , Animales , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único/métodos , Péptidos/metabolismo , Bacteriocinas/metabolismo
2.
Int J Mol Sci ; 24(22)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-38003394

RESUMEN

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.


Asunto(s)
Medios de Contraste , Nanopartículas , Ratones , Animales , Polímeros , Aminas , Zinc , Distribución Tisular , Imagen por Resonancia Magnética/métodos , Compuestos Férricos , Preparaciones Farmacéuticas
3.
Cell Mol Life Sci ; 78(23): 7589-7604, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34665280

RESUMEN

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.


Asunto(s)
Modelos Animales de Enfermedad , Vesículas Extracelulares/metabolismo , Hepatocitos/metabolismo , Hiperlipidemias/fisiopatología , Hígado/metabolismo , Animales , Dieta Alta en Grasa , Masculino , Ratones , Ratones Endogámicos C57BL
4.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36232467

RESUMEN

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.


Asunto(s)
Catequina , Dendrímeros , Vitis , Antioxidantes/farmacología , Antivirales/análisis , Flavonoides/farmacología , Humanos , Hipoglucemiantes/análisis , Polifenoles/análisis , Polifenoles/farmacología , Polifenoles/uso terapéutico , Quercetina/análisis , Resveratrol , Semillas/química , Vitis/química
5.
Int J Mol Sci ; 22(19)2021 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-34638688

RESUMEN

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.


Asunto(s)
Doxorrubicina , Ácido Fólico , Nanopartículas , Neoplasias de la Mama Triple Negativas , Animales , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacología , Femenino , Citometría de Flujo , Ácido Fólico/química , Ácido Fólico/farmacología , Humanos , Masculino , Ratones , Ratones Desnudos , Nanopartículas/química , Nanopartículas/uso terapéutico , Neoplasias de la Mama Triple Negativas/diagnóstico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Int J Mol Sci ; 22(9)2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33922728

RESUMEN

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.


Asunto(s)
Modelos Animales de Enfermedad , Glucosa/metabolismo , Linfoma/patología , Imagen Multimodal/métodos , Animales , Fluorodesoxiglucosa F18/metabolismo , Inyecciones Intraperitoneales , Metástasis Linfática , Linfoma/diagnóstico por imagen , Ratones , Ratones Endogámicos BALB C , Micrometástasis de Neoplasia , Tomografía de Emisión de Positrones/métodos , Radiofármacos/metabolismo , Tomografía Computarizada por Rayos X/métodos
7.
Chemistry ; 26(9): 1989-2001, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-31755596

RESUMEN

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.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/química , Quelantes/química , Cobre/química , Radiofármacos/química , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/síntesis química , Línea Celular Tumoral , Cetuximab/química , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Reacción de Cicloadición , Humanos , Ratones , Microscopía Fluorescente , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos/síntesis química , Trasplante Heterólogo
8.
Int J Mol Sci ; 21(17)2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32867390

RESUMEN

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.


Asunto(s)
Neoplasias Asociadas a Colitis/genética , Interleucina-6/genética , Trombocitosis/genética , Animales , Azoximetano/efectos adversos , Neoplasias Asociadas a Colitis/inducido químicamente , Neoplasias Asociadas a Colitis/complicaciones , Neoplasias Asociadas a Colitis/diagnóstico por imagen , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Imagen por Resonancia Magnética , Masculino , Ratones , Recuento de Plaquetas , Tomografía de Emisión de Positrones , Trombocitosis/sangre , Trombocitosis/etiología , Trombocitosis/metabolismo , Trombopoyetina/metabolismo
9.
Am J Physiol Heart Circ Physiol ; 311(4): H927-H943, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27521417

RESUMEN

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.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Hipertrofia Ventricular Izquierda/metabolismo , Mitocondrias Cardíacas/metabolismo , Estrés Oxidativo , Estado Prediabético/metabolismo , Disfunción Ventricular Izquierda/metabolismo , Adipoquinas/metabolismo , Tejido Adiposo , Animales , Apoptosis , Autofagia , Composición Corporal , Proteínas de Unión al Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatología , Diabetes Mellitus Experimental/fisiopatología , Neuropatías Diabéticas , Diástole , Dieta Alta en Grasa , Ecocardiografía , GTP Fosfohidrolasas , Proteínas de Choque Térmico/metabolismo , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Proteínas de la Membrana/metabolismo , Microscopía Electrónica , Mitocondrias Cardíacas/ultraestructura , Proteínas Mitocondriales/metabolismo , Mitofagia , Miocardio/metabolismo , Miocardio/ultraestructura , Fosforilación , Estado Prediabético/fisiopatología , Ratas , Ratas Long-Evans , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Sarcolema , Serina-Treonina Quinasas TOR/metabolismo , Disfunción Ventricular Izquierda/fisiopatología , Presión Ventricular
10.
Bioconjug Chem ; 27(2): 319-28, 2016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26172432

RESUMEN

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.


Asunto(s)
Óxido Ferrosoférrico/química , Fluoruros/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Imagen Óptica/métodos , Tomografía de Emisión de Positrones/métodos , Itrio/química , Animales , Difosfonatos/química , Difosfonatos/farmacocinética , Óxido Ferrosoférrico/farmacocinética , Fluoruros/farmacocinética , Masculino , Ratones Endogámicos C57BL , Ratones Desnudos , Imagen Multimodal/métodos , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Tomografía Computarizada de Emisión de Fotón Único/métodos , Itrio/farmacocinética
11.
BMC Med Imaging ; 16: 14, 2016 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-26864653

RESUMEN

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.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Interpretación de Imagen Asistida por Computador/métodos , Enfermedades Pulmonares/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Animales , Modelos Animales de Enfermedad , Femenino , Fractales , Humanos , Enfermedades Pulmonares/inducido químicamente , Ratones , Ratones Endogámicos BALB C , Distribución Normal
13.
Geroscience ; 45(4): 2179-2193, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36879183

RESUMEN

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.


Asunto(s)
COVID-19 , Humanos , Ivermectina/uso terapéutico , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19 , Resultado del Tratamiento
14.
Int J Nanomedicine ; 18: 2071-2086, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37113796

RESUMEN

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.


Asunto(s)
Medios de Contraste , Nanopartículas de Magnetita , Ratas , Animales , Porcinos , Óxido Ferrosoférrico , Seguridad del Paciente , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/toxicidad
15.
Front Immunol ; 14: 1204543, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37383226

RESUMEN

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.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Humanos , Enzima Convertidora de Angiotensina 2 , Tratamiento Farmacológico de COVID-19
16.
Sci Rep ; 13(1): 18752, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37907509

RESUMEN

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.


Asunto(s)
Escherichia coli , Vesículas Extracelulares , Animales , Ratones , Escherichia coli/metabolismo , Membrana Externa Bacteriana/metabolismo , Distribución Tisular , Vesículas Extracelulares/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Imagen Molecular
17.
Sci Rep ; 12(1): 19441, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36376345

RESUMEN

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.


Asunto(s)
Endotoxemia , Neoplasias Hepáticas , Humanos , Ratas , Animales , Masculino , Hepatectomía/métodos , Vena Porta/cirugía , Antígeno Ki-67 , Ejercicio Preoperatorio , Resultado del Tratamiento , Ratas Wistar , Hígado/cirugía , Regeneración Hepática , Ligadura , Modelos Teóricos
18.
Res Rep Urol ; 14: 193-202, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35572814

RESUMEN

Purpose: A number of studies have confirmed that elevated platelet count accompanying various solid tumours is associated with worse survival. However, only meagre data are available on the relationship between thrombocytosis and survival in prostate cancer. Methods: We conducted a retrospective analysis on clinical-pathological data accumulated from 316 patients during on average 51 months of follow-up after laparoscopic prostatectomy performed for prostate cancer. We analyzed the relationship between platelet count, risk factors, prostate-specific antigen (PSA) and cancer stage with use the Tumor, Node, Metastase system (TNM), as well as surgical margin, and prognosis. Results: Thrombocytosis occurred in only one out of the 316 patients. The multivariate Cox proportional hazard model showed that preoperative PSA, risk group, preoperative haemoglobin level, and surgical margin status were significant, independent predictors of biochemical progression-free survival. By contrast, age at diagnosis and thrombocytosis had no such predictive value. Conclusion: We could not demonstrate an association between elevated platelet count and worse survival in our study population of patients with prostate cancer.

19.
Foods ; 11(5)2022 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-35267328

RESUMEN

(1) Background: Humic substances are well-known human nutritional supplement materials and they play an important performance-enhancing role as animal feed additives. For decades, ingredients of humic substances have been proven to carry potent antiviral effects against different viruses. (2) Methods: Here, the antiviral activity of a humic substance containing ascorbic acid, Se- and Zn2+ ions intended as a nutritional supplement material was investigated against SARS-CoV-2 virus B1.1.7 Variant of Concern ("Alpha Variant") in a VeroE6 cell line. (3) Results: This combination has a significant in vitro antiviral effect at a very low concentration range of its intended active ingredients. (4) Conclusions: Even picomolar concentration ranges of humic substances, Vitamin C and Zn/Se ions in the given composition, were enough to achieve 50% viral replication inhibition in the applied SARS-CoV-2 virus inhibition test.

20.
Front Oncol ; 12: 820136, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35756658

RESUMEN

Purpose: For the identification of high-risk patients in diffuse large B-cell lymphoma (DLBCL), we investigated the prognostic significance of in vivo radiomics derived from baseline [18F]FDG PET/CT and clinical parameters. Methods: Pre-treatment [18F]FDG PET/CT scans of 85 patients diagnosed with DLBCL were assessed. The scans were carried out in two clinical centers. Two-year event-free survival (EFS) was defined. After delineation of lymphoma lesions, conventional PET parameters and in vivo radiomics were extracted. For 2-year EFS prognosis assessment, the Center 1 dataset was utilized as the training set and underwent automated machine learning analysis. The dataset of Center 2 was utilized as an independent test set to validate the established predictive model built by the dataset of Center 1. Results: The automated machine learning analysis of the Center 1 dataset revealed that the most important features for building 2-year EFS are as follows: max diameter, neighbor gray tone difference matrix (NGTDM) busyness, total lesion glycolysis, total metabolic tumor volume, and NGTDM coarseness. The predictive model built on the Center 1 dataset yielded 79% sensitivity, 83% specificity, 69% positive predictive value, 89% negative predictive value, and 0.85 AUC by evaluating the Center 2 dataset. Conclusion: Based on our dual-center retrospective analysis, predicting 2-year EFS built on imaging features is feasible by utilizing high-performance automated machine learning.

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