In vivo imaging of glycol chitosan-based nanogel biodistribution

The preclinical development of nanomedicines raises several challenges and requires a comprehensive characterization. Among them is the evaluation of the biodistribution following systemic administration. In previous work, the biocompatibility and in vitro targeting ability of a glycol chitosan (GC) based nanogel have been validated. In the present study, its biodistribution in the mice is assessed, using near-infrared (NIR) fluorescence imaging as a tool to track the nanogel over time, after intravenous administration. Rapid whole body biodistribution of both Cy5.5 labeled GC nanogel and free polymer is found at early times. It remains widespreadly distributed in the body at least up to 6 h postinjection and its concentration then decreases drastically after 24 h. Nanogel blood circulation half-life lies around 2 h with the free linear GC polymer presenting lower blood clearance rate. After 24 h, the blood NIR fluorescence intensity associated with both samples decreases to insignificant values. NIR imaging of the organs shows that the nanogel had a body clearance time of 48 h, because at this time point a weak signal of NIR fluorescence is observed only in the kidneys. Hereupon it can be concluded that the engineered GC nanogel has a fairly long blood circulation time, suitable for biomedical applications, namely, drug delivery, simultaneously allowing efficient and quick body clearance.Acknowledgements: The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), and the Project “BioHealth— Biotechnology and Bioengineering approaches to improve health quality,” Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2-O Novo Norte), QREN, FEDER. The authors also thank António Temudo, Dolores Bonaparte, and Sílvia Santos Pedrosa for the support on in vivo assays. Paula Pereira acknowledges FCT for the PhD grant SFRH/ BD/64977/2009

GSE4‐loaded nanoparticles a potential therapy for lung fibrosis that enhances pneumocyte growth, reduces apoptosis and DNA damage

Idiopathic pulmonary fibrosis is a lethal lung fibrotic disease, associated with aging with a mean survival of 2-5 years and no curative treatment. The GSE4 peptide is able to rescue cells from senescence, DNA and oxidative damage, inflammation, and induces telomerase activity. Here, we investigated the protective effect of GSE4 expression in vitro in rat alveolar epithelial cells (AECs), and in vivo in a bleomycin model of lung fibrosis. Bleomycin-injured rat AECs, expressing GSE4 or treated with GSE4-PLGA/PEI nanoparticles showed an increase of telomerase activity, decreased DNA damage, and decreased expression of IL6 and cleaved-caspase 3. In addition, these cells showed an inhibition in expression of fibrotic markers induced by TGF-β such as collagen-I and III among others. Furthermore, treatment with GSE4-PLGA/PEI nanoparticles in a rat model of bleomycin-induced fibrosis, increased telomerase activity and decreased DNA damage in proSP-C cells. Both in preventive and therapeutic protocols GSE4-PLGA/PEI nanoparticles prevented and attenuated lung damage monitored by SPECT-CT and inhibited collagen deposition. Lungs of rats treated with bleomycin and GSE4-PLGA/PEI nanoparticles showed reduced expression of α-SMA and pro-inflammatory cytokines, increased number of pro-SPC-multicellular structures and increased DNA synthesis in proSP-C cells, indicating therapeutic efficacy of GSE4-nanoparticles in experimental lung fibrosis and a possible curative treatment for lung fibrotic patients

Metodología del lavado, purgado y ventilado de tanques de carga en petrolero, mediante un caso de cálculo práctico

El presente trabajo trata de un estudio de la metodología para el lavado, purgado y ventilado de tanques de carga de un petrolero. El desarrollo del presente se diversifica en dos capítulos importantes, metodología y desarrollo. La idea general que se va a plantear, durante estos dos capítulos, es el estudio del desarrollo de un plan para realizar la operación antes citada. En el primer capítulo se van a plantear los elementos principales para su ejecución y en su segundo capítulo se van a desarrollar en diferentes fases. Es este último capítulo, cuando se plantean las diferentes variantes para la ejecución según el llenado de uno o dos SLOP´s, según el plan de una limpieza total del buque, partiendo del COW total hasta la limpieza con agua final, según el plan de purgado y ventilado y, finalmente, el minimizado del agua usada por el ODME Los diferentes planes relatados, así como, los cálculos realizados se basan en la experiencia y los equipos que se utilizan a bordo de buques petroleros

Metodología del lavado, purgado y ventilado de tanques de carga en petrolero, mediante un caso de cálculo práctico

El presente trabajo trata de un estudio de la metodología para el lavado, purgado y ventilado de tanques de carga de un petrolero. El desarrollo del presente se diversifica en dos capítulos importantes, metodología y desarrollo. La idea general que se va a plantear, durante estos dos capítulos, es el estudio del desarrollo de un plan para realizar la operación antes citada. En el primer capítulo se van a plantear los elementos principales para su ejecución y en su segundo capítulo se van a desarrollar en diferentes fases. Es este último capítulo, cuando se plantean las diferentes variantes para la ejecución según el llenado de uno o dos SLOP´s, según el plan de una limpieza total del buque, partiendo del COW total hasta la limpieza con agua final, según el plan de purgado y ventilado y, finalmente, el minimizado del agua usada por el ODME Los diferentes planes relatados, así como, los cálculos realizados se basan en la experiencia y los equipos que se utilizan a bordo de buques petroleros

Metodología del lavado, purgado y ventilado de tanques de carga en petrolero, mediante un caso de cálculo práctico

El presente trabajo trata de un estudio de la metodología para el lavado, purgado y ventilado de tanques de carga de un petrolero. El desarrollo del presente se diversifica en dos capítulos importantes, metodología y desarrollo. La idea general que se va a plantear, durante estos dos capítulos, es el estudio del desarrollo de un plan para realizar la operación antes citada. En el primer capítulo se van a plantear los elementos principales para su ejecución y en su segundo capítulo se van a desarrollar en diferentes fases. Es este último capítulo, cuando se plantean las diferentes variantes para la ejecución según el llenado de uno o dos SLOP´s, según el plan de una limpieza total del buque, partiendo del COW total hasta la limpieza con agua final, según el plan de purgado y ventilado y, finalmente, el minimizado del agua usada por el ODME Los diferentes planes relatados, así como, los cálculos realizados se basan en la experiencia y los equipos que se utilizan a bordo de buques petroleros

Bionanopartículas biodegradables para liberación del péptido GSE24-2, procedimiento de obtención y utilización

[EN] The invention relates to biodegradable PLGA bionanoparticles encapsulating the GSE24-2 peptide with telomerase activity, and to pharmaceutical, cosmetic and biotechnological compositions comprising same. The pharmaceutical compositions are useful for treating diseases presenting a telomerase deficiency, such as dyskeratosis congenita, and diseases presenting ageing characteristics, such as Werner syndrome, Rothmund Thompson syndrome, and other diseases where there is DNA damage such as ataxia telangiectasia. The relation also relates to the method for producing said bionanoparticles by means of a w/o/w double emulsion technique.[FR] L'objet de l'invention concerne des bionanoparticules biodégradables de PLGA, dans lesquelles est encapsulé le peptide GSE24-2 à activité télomérase, et des compositions pharmaceutiques, cosmétiques, et biotechnologiques qui les contiennent. Les compositions pharmaceutiques sont utiles pour le traitement de maladies qui présentent un déficit en télomérase, comme la dyskératose congénitale, ainsi que des maladies qui se traduisent par un vieillissement, tel que le syndrome de Werner, de Rothmund Thompson, et d'autres maladies présentant des dommages de l'ADN comme l'ataxie télangiectasie. L'invention concerne également un procédé d'obtention desdites bionanoparticules au moyen d'une technique d'émulsion double w/o/w.[ES] El objeto de la invención se refiere a bionanopartículas biodegradables de PLGA en las cuales se ha encapsuladoel péptido GSE24-2con actividad telomerasa y composiciones farmacéuticas, cosméticas y biotecnológicas que las comprendan. Las composiciones farmacéuticas son útiles para el tratamiento de enfermedades que cursan con déficit telomerasa, como la disqueratosis congénita, así como enfermedades que cursen con envejecimiento, como el síndrome de Werner, de Rothmund Thompson, y de otras enfermedades donde haya un daño en el ADN como la ataxia telangiectasia. Igualmente, se describe el procedimiento de obtención de dichas bionanopartículas mediante una técnica de doble emulsión w/o/w.Peer reviewedConsejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Universidad del País Vasco, Centro de Investigaciones Biomédicas en Red de Enfermedades RarasA1 Solicitud de patente con informe sobre el estado de la técnic

Development and validation of a rapid HPLC method for the quantification of GSE4 peptide in biodegradable PEI-PLGA nanoparticles

et al.In this work a high performance liquid chromatographic (HPLC) method has been developed and validated for the content determination of GSE4 peptide in PEI-PLGA nanoparticles. Chromatographic separation was performed on a C18 column, and a gradient elution with a mobile phase composed of methanol and 0.1% aqueous trifluoroacetic acid (TFA) solution, at a flow rate of 1ml/min, was used. GSE4 peptide identification was made by fluorescence detection at 290nm. The elution of methanol:TFA was initially maintained at (20:80, v/v) for one min and the gradient changed to (80:20, v/v) in 6min. This ratio was then followed by isocratic elution at (80:20, v/v) during another min and for further 3min it was linearly modified to (20:80, v/v). The developed method was validated according to the ICH guidelines, being specific, linear in the range 10-100μg/ml (R2=0.9996), precise, exhibiting good inter-day and intra-day precision reflected by the relative standard deviation values (less than 3.88%), accurate, with a recovery rate of 100.18±0.95%, and stable for 48h at 5°C or at RT when encapsulated in nanoparticles. The method was simple, fast, and successfully used to determine the peptide content in GSE4-loaded PEI-PLGA nanoparticles.S.P. Egusquiaguirre thanks the Basque Government (Departamento de Educación, Universidades e Investigación) for the fellowship research grant. We also acknowledge financial support from the Spanish Government (Ministerio de Economia y Competitividad) for the Subprogram INNPACTO (IPT-2012-0674-090000) and FEDER funds.Peer Reviewe

Optoacoustic imaging enabled biodistribution study of cationic polymeric biodegradable nanoparticles.

Nanosized contrast agents for molecular imaging have attracted widespread interest for diagnostic applications with high resolution in medicine. However, many solid nanoparticles exhibit a great potential to induce toxicity, hindering their use for clinical applications. On the other hand, near-infrared (NIR) dyes have also been used for extensive biological applications, but show some limitations due to their poor aqueous stability, tendency to aggregation and rapid elimination from the body. An alternative proposed in this work to overcome these limitations is the use of NIR dye-loaded nanoparticles. Here we introduce nanoparticles constructed with poly(D,L-lactide-co-glycolic acid) (PLGA), a biodegradable and biocompatible polymer widely used for biomedical applications, attached to the polycation polyethyleneimine (PEI) to obtain positively charged nanoparticles. The in vivo biodistribution of the cationic PEI-PLGA nanoparticles was investigated after administration through three different routes (intravenous, intraperitoneal and subcutaneous) using multispectral optoacoustic tomography (MSOT). The prepared nanoparticles exhibited good colloidal stability and adequate optical properties for optoacoustic imaging. The in vivo biodistribution assays indicated a strong accumulation of the particles in the liver and spleen, and retention in these organs for at least 24 h. Therefore, these nanoparticles could find promising applications in MSOT due to a sharp and characteristic optoacoustic spectrum and high optoacoustic signal generation, and become a promising building block for theranostic strategies

Development of surface modified biodegradable polymeric nanoparticles to deliver GSE24.2 peptide to cells: A promising approach for the treatment of defective telomerase disorders

et al.The aim of the present study was to develop a novel strategy to deliver intracellularly the peptide GSE24.2 for the treatment of Dyskeratosis congenita (DC) and other defective telomerase disorders. For this purpose, biodegradable polymeric nanoparticles using poly(lactic-co-glycolic acid) (PLGA NPs) or poly(lactic-co-glycolic acid)-poly ethylene glycol (PLGA-PEG NPs) attached to either polycations or cell-penetrating peptides (CPPs) were prepared in order to increase their cellular uptake. The particles exhibited an adequate size and zeta potential, with good peptide loading and a biphasic pattern obtained in the in vitro release assay, showing an initial burst release and a later sustained release. GSE24.2 structural integrity after encapsulation was assessed using SDS-PAGE, revealing an unaltered peptide after the NPs elaboration. According to the cytotoxicity results, cell viability was not affected by uncoated polymeric NPs, but the incorporation of surface modifiers slightly decreased the viability of cells. The intracellular uptake exhibited a remarkable improvement of the internalization, when the NPs were conjugated to the CPPs. Finally, the bioactivity, addressed by measuring DNA damage rescue and telomerase reactivation, showed that some formulations had the lowest cytotoxicity and highest biological activity. These results proved that GSE24.2-loaded NPs could be delivered to cells, and therefore, become an effective approach for the treatment of DC and other defective telomerase syndromes.Susana P. Egusquiaguirre thanks the Basque Government (Gobierno Vasco, Departamento de Educación, Universidades e Investigación) for the fellowship research grant. C. Manguan-García is supported by CIBER de Enfermedades Raras. This project was partially supported by the Basque Government (Consolidated Groups, IT-407-07), MINECO from the Spanish Government (INNPACTO, IPT-2012-0674-090000). The authors gratefully acknowledge the support of University of the Basque Country UPV/EHU (UFI11/32). Besides, this work was also supported by grant PI11-00949 (supported by FEDER funds) from Instituto Carlos III.Peer Reviewe