325 results on '"Pedraz J"'
Search Results
102. Long-term immune response in mice following subcutaneous administration of BSA-PLGA microspheres
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Pedraz, J. L., MANUELA IGARTUA, Hernandez, R. M., Esquisabel, A., Gascon, A. R., and Calvo, B.
103. Emerging therapeutic approaches based on nanotechnology for the treatment of diseases associated with telomere dysfunction
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Egusquiaguirre, S. P., Pedraz, J. L., Hernández, R. M., and MANUELA IGARTUA
104. Novel drug delivery systems for releasing growth factors to the CNS: Focus on Alzheimer's and Parkinson's diseases
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Herran, E., MANUELA IGARTUA, Pedraz, J. L., and Hernandez, R. M.
105. Preliminary assesment of the immune reponse to Olea europaea pollen extracts encapsulated into PLGA microspheres
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Pedraz, J. L., MANUELA IGARTUA, Hernandez, R. M., Gutierro, I., Gascon, A. R., and Calvo, B.
106. Purification of alginate encapsulated cells in a 3D printed microfluidic magnetic sorting device
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Etxebarria-Elezgarai, J., Espona-Noguera, A., Saez, J., Cañibano-Hernández, A., Orive, G., Rosa Maria Hernandez, Saenz Del Burgo, L., Benito-Lopez, F., Ciriza, J., Pedraz, J. L., and Basabe-Desmonts, L.
107. Mass transfer ranking of polylysine, poly-ornithine and poly-methylene-co-guanidine microcapsule membranes using a single low molecular mass marker
- Author
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Rosinski Stefan, Lewinska Dorota, Orive Gorka, and Pedraz Jose Luis
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Overall mass transfer coefficient ,Alginate microcapsules ,Poly-L-lysine ,Poly-L-ornithine ,Poly-methylene-co-guanidine ,Cell encapsulation ,Chemical technology ,TP1-1185 - Abstract
On the long way to clinical transplantable hybrid systems, comprising of cells, acting as immuno-protected bioreactors microencapsulated in a polymeric matrix and delivering desired factors (proteins, hormones, enzymes etc) to the patient's body, an important step is the optimization of the microcapsule. This topic includes the selection of a proper coating membrane which could fulfil, first of all, the mass transfer as well as biocompatibility, stability and durability requirements. Three different membranes from polymerised aminoacids, formed around exactly identical alginate gel cores, were considered, concerning their mass transport properties, as potential candidates in this task. The results of the evaluation of the mass ingress and mass transfer coefficient h for the selected low molecular mass marker, vitamin B12, in poly-L-lysine (HPLL) poly-L-ornithine (HPLO) and poly-methylene-co-guanidine hydrochloride (HPMCG) membrane alginate microcapsules demonstrate the advantage of using the mass transfer approach to a preliminary screening of various microcapsule formulations. Applying a single marker and evaluating mass transfer coefficients can help to quickly rank the investigated membranes and microcapsules according to their permeability. It has been demonstrated that HPLL, HPLO and HPMCG microcapsules differ from each other by a factor of two concerning the rate of low molecular mass marker transport. Interesting differences in mass transfer through the membrane in both directions in-out was also found, which could possibly be related to the membrane asymmetry.
- Published
- 2003
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108. Bioavailability of intramuscular vitamin E acetate in rabbits
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Pedraz, J L, primary, Calvo, B, additional, Bortolotti, A, additional, Celardo, A, additional, and Bonati, M, additional
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- 1989
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109. On the employment of lambda-carrageenan in a matrix system. II. lambda-Carrageenan and hydroxypropylmethylcellulose mixtures
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Bonferoni, M. C., Rossi, S., Tamayo, M., and Pedraz, J. L.
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- 1994
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110. On the employment of lambda-carrageenan in a matrix system. I. Sensitivity to dissolution medium and comparison with Na carboxymethylcellulose and xanthan gum
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Bonferoni, M. C., Rossi, S., Tamayo, M., and Pedraz, J. L.
- Published
- 1993
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111. PHARMACOKINETICS AND DISTRIBUTION OF KETAMINE AFTER EXTRADURAL ADMINISTRATION TO DOGS
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PEDRAZ, J. L., CALVO, M. B., GASCON, A. R., HERNANDEZ, R., MURIEL, C., TORRES, L. M., and DOMINGUEZ-GIL, A.
- Abstract
We have studied the pharmacokinetics and distribution of ketamine and its biotransformation products in dogs after extradural administration of ketamine at L4–5. The mean apparent uptake rate constants of ketamine for plasma and CSF were 4.17 (SD 1.84) and 5.15 (2.50) h−1 respectively. The concentrations of ketamine in CSF were greater than those found in plasma. The elimination half-life values of the parent drug for both biological fluids were similar (4.3 (2.96) h and 4.6 (3.31) h for plasma and CSF, respectively). The apparent formation rate constant of norketamine was greater than that of dehydronorketamine. However, the concentrations of the biotransformation products in CSF were smaller than those of the parent drug. These results are similar to the distribution of ketamine and its metabolites in different cerebral structures and tissues. The concentrations decreased in concert with the increase in polarity of the metabolites. A specific distribution for all compounds was observed. Ketamine showed eater affinity for brainstem, while norketamine and dehydronorketamine were distributed mostly in cerebellum and kidney, respectively.
- Published
- 1991
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112. PHARMACOKINETICS OF RECTAL KETAMINE IN CHILDREN
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PEDRAZ, J. L., CALVO, M. B., LANAO, J. M., MURIEL, C., LAMAS, J. SANTOS, and DOMINGUEZ-GIL, A.
- Abstract
We have studied the pharmacokinetics of ketamine administered rectally in a dose of 10 mg kg−1 to five children aged 6–9 yr and mean weight 28.80 (SD 6.55) kg. An acceptable level of anaesthesia was not obtained in any patient. Despite this, the degree of analgesia obtained was good and no child required further administration of analgesics during the postoperative period. Tolerance to the suppositories was excellent. The absorption of ketamine was found to be relatively fast, with a median peak concentration of 160 ng ml−1 (range 96–250 ng ml−1) at 0.75 h (range 0.50–1.00 h) after administration. The plasma concentrations of norketamine were greater than those of the parent drug, with a maximum of 510 ng ml−1 (range 450–810 ng ml−1) at 0.81 h (range 0.50–1.00 h) after administration. The medians of the half-lives of ketamine and norketamine were 3.15 h and 2.56 h, respectively (range 1.57–4.95 h and 1.47–5.30 h, respectively).
- Published
- 1989
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113. [Neonatal seizures and progression to epilepsy in a tertiary hospital].
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Hernández-Prieto A, Garrido-Martín M, Gómez-Martín H, Pablos-López A, Alonso-Díez C, Hernández-Fabián A, Justel-Rodríguez M, Garrido-Pedraz JM, and Prieto-Matos P
- Subjects
- Infant, Newborn, Humans, Tertiary Care Centers, Seizures etiology, Affect, Hospitalization, Epilepsy etiology, Hypoxia-Ischemia, Brain complications
- Abstract
Introduction: Given the immaturity of the newborn, neonatal seizures are a diagnostic challenge. Most of them are secondary to an acute event. A small percentage constitute the onset of epilepsy., Aims: The aim was to analyse neonates with a diagnosis of seizures admitted to a tertiary hospital between November 2009 and May 2021, and their subsequent progression to epilepsy., Material and Methods: A retrospective observational study was carried out using the hospital database. Information was collected on neonates with a discharge diagnosis of 'seizures' or 'moderate or severe hypoxic-ischaemic encephalopathy'. Different variables were analysed: aetiology of the seizures, type, persistence over time, treatment and electroclinical correlates., Results: Of 165 patients, 55 presented neonatal seizures. As regards aetiology, 43 patients (78%) had seizures secondary to an acute event, of which 19 (34%) were hypoxic-ischaemic encephalopathies, and 22 (40%) had other acute disorders. Genetic alteration was found in six of them (11%). Thirteen patients (24%) progressed to subsequent epilepsy, of whom seven had symptomatic epilepsy, with a period of latency after the acute event in two patients. Six patients had neonatal epilepsy with unprovoked seizures. Twenty-two (62%) showed electroclinical correlates. All of the confirmed crises (100%) were focal. All the seizures were treated. The drug of choice was phenobarbital., Conclusions: Diagnosis of neonatal seizures requires high clinical suspicion and electroclinical confirmation. Most of them progress favourably, but a percentage constitute the onset of epilepsy, the identification of which will determine their therapeutic management.
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- 2023
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114. Co-delivering of oleuropein and lentisk oil in phospholipid vesicles as an effective approach to modulate oxidative stress, cytokine secretion and promote skin regeneration.
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Sklenarova R, Allaw M, Perra M, Castangia I, Frankova J, Luis Pedraz J, Letizia Manca M, and Manconi M
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- Humans, Skin metabolism, Oxidative Stress, Wound Healing, Cytokines metabolism, Phospholipids metabolism, Liposomes metabolism
- Abstract
In this work oleuropein and lentisk oil have been co-loaded in different phospholipid vesicles (i.e., liposomes, transfersomes, hyalurosomes and hyalutransfersomes), to obtain a formulation capable of both inhibiting the production of different markers connected with inflammation and oxidative stress and promoting the skin repair. Liposomes were prepared using a mixture of phospholipids, oleuropein and lentisk oil. Tween 80, sodium hyaluronate or their combination have been added to the mixture to obtain transfersomes, hyalurosomes and hyalutransfersomes. Size, polydispersity index, surface charge and stability on storage was evaluated. The biocompatibility, anti-inflammatory activity and wound healing effect were tested using normal human dermal fibroblasts. Vesicles were small (mean diameter ∼ 130 nm) and homogeneously dispersed (polydispersity index ∼ 0.14), highly negatively charged (zeta potential 02053-64 mV) and capable of loading 20 mg/mL of oleuropein and 75 mg/mL of lentisk oil. The freeze-drying of dispersions with a cryoprotectant permitted to improve their stability on storage. The co-loading of oleuropein and lentisk oil in vesicles inhibited the overproduction of inflammatory markers, especially MMP-1 and IL-6, counteracted the oxidative stress induced in cells using hydrogen peroxide, and promoted the healing of a wounded area performed in vitro in a cell monolayer of fibroblasts. The proposed co-loading of oleuropein and lentisk oil in natural-based phospholipid vesicles may hold promising therapeutic value especially for the treatment of a wide variety of skin disorders., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
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115. First report of canine morbillivirus infection of adipose tissue-derived stem cells from dogs with distemper.
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Altamirano-Samaniego F, Enciso-Benavides J, Rojas N, Manuel Iglesias-Pedraz J, Enciso N, Fossatti M, and Enciso J
- Abstract
Background and Aim: Ribonucleic acid viruses remain latent in different cell types, including mesenchymal stem cells; however, the distemper virus remains undetected in these cells. This study aimed to determine whether adipose stem cells (ASCs) from dogs with distemper disease are infected with the canine morbillivirus (CM)., Materials and Methods: Twelve dogs with the neurological phase of the disease and who were positive for CM by reverse transcription polymerase chain reaction (RT-PCR), were studied. ASCs from adipose tissue of the lesser omentum of these infected dogs were isolated and characterized. Direct fluorescence was used to detect the viral antigen in cell cultures. Flow cytometry and RT-PCR identified detectable quantities of the virus in two cultures, while electron microscopy confirmed the CM particles within ASCs., Results: This study revealed that ASCs of the omentum of dogs with distemper disease can be infected with CM, indicating their possible involvement in this virus latency and persistence. This suggests that its detection should be considered within the quality control process of stem cells intended for regenerative medicine., Conclusion: To the best of our knowledge, this is the first study that demonstrates that omentum ASCs from dogs with distemper disease can be infected with CM and may be involved in viral latency or persistence. Our study also suggests that the detection of CM should be considered within the quality control process of stem cells intended for regenerative medicine., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Altamirano-Samaniego, et al.)
- Published
- 2022
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116. Bioinspired gelatin/bioceramic composites loaded with bone morphogenetic protein-2 (BMP-2) promote osteoporotic bone repair.
- Author
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Echave MC, Erezuma I, Golafshan N, Castilho M, Kadumudi FB, Pimenta-Lopes C, Ventura F, Pujol A, Jimenez JJ, Camara JA, Hernáez-Moya R, Iturriaga L, Sáenz Del Burgo L, Iloro I, Azkargorta M, Elortza F, Lakshminarayanan R, Al-Tel TH, García-García P, Reyes R, Delgado A, Évora C, Pedraz JL, Dolatshahi-Pirouz A, and Orive G
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- Animals, Ceramics chemistry, Gelatin chemistry, Humans, Mice, Tissue Scaffolds, Bone Morphogenetic Protein 2 pharmacology, Drug Carriers chemistry, Osteogenesis, Osteoporosis drug therapy
- Abstract
There are currently several commercialized products approved by the Food and Drug Administration and the European Medicines Agency based on the use of recombinant human BMP-2 for the treatment of non-unions long fractures and spinal fusion. However, the adverse effects recorded with the use of BMPs suggest the need for drug delivery carriers that allow reducing the required doses and improve their cost-effectiveness. Herein, we have developed a new osteoconductive scaffold that reduces the required doses of BMP-2 for promoting bone regeneration in an osteoporotic defect model. The composite is, in brief, a gelatin-based 3D scaffold reinforced with either calcium sulfate or hydroxyapatite as an inorganic osteoconductive biomaterial. To this end, the organic/inorganic composite systems showed high hydration capacity and good in vitro degradability. The incorporation of 7.5% (m/v) ceramic compounds resulted in scaffolds with stiffer Young modulus (179 and 75 kPa for CaSO
4 _7 and HA_7, respectively) than bare gelatin hydrogels (48 kPa). Studies with human bone-marrow derived mesenchymal stem cells (hBM-MSCs) revealed that the 3D scaffolds promote cell adhesion and proliferation along with osteogenic differentiation capabilities. Specifically, downregulation of stemness (Nanog, Oct4) genes and upregulation of osteogenic markers (ALP, Col1a1, Fmod) by two fold were observed over 10 days under basal culture conditions. Promisingly, the sustained in vitro release of BMP-2 observed from the porous reinforced scaffolds allowed us to address the critical-sized osteoporotic mice calvarial defects with a relatively low growth factor doses (600 ng BMP-2/scaffold) compared to conventional doses at 2-15 micrograms. Overall, this study demonstrates the promising potential of osteoconductive gelatin/calcium bioceramics composites as osteogenic growth factors delivery carriers for bone-regeneration via ultra-low growth factor doses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2022
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117. Development, characterization and sterilisation of Nanocellulose-alginate-(hyaluronic acid)- bioinks and 3D bioprinted scaffolds for tissue engineering.
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Lafuente-Merchan M, Ruiz-Alonso S, Espona-Noguera A, Galvez-Martin P, López-Ruiz E, Marchal JA, López-Donaire ML, Zabala A, Ciriza J, Saenz-Del-Burgo L, and Pedraz JL
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- Alginates, Hyaluronic Acid, Printing, Three-Dimensional, Sterilization, Tissue Scaffolds, Bioprinting, Tissue Engineering
- Abstract
3D-bioprinting is an emerging technology of high potential in tissue engineering (TE), since it shows effective control over scaffold fabrication and cell distribution. Biopolymers such as alginate (Alg), nanofibrillated cellulose (NC) and hyaluronic acid (HA) offer excellent characteristics for use as bioinks due to their excellent biocompatibility and rheological properties. Cell incorporation into the bioink requires sterilisation assurance, and autoclave, β-radiation and γ-radiation are widely used sterilisation techniques in biomedicine; however, their use in 3D-bioprinting for bioinks sterilisation is still in their early stages. In this study, different sterilisation procedures were applied on NC-Alg and NC-Alg-HA bioinks and their effect on several parameters was evaluated. Results demonstrated that NC-Alg and NC-Alg-HA bioinks suffered relevant rheological and physicochemical modifications after sterilisation; yet, it can be concluded that the short cycle autoclave is the best option to sterilise both NC-Alg based cell-free bioinks, and that the incorporation of HA to the NC-Alg bioink improves its characteristics. Additionally, 3D scaffolds were bioprinted and specifically characterized as well as the D1 mesenchymal stromal cells (D1-MSCs) embedded for cell viability analysis. Notably, the addition of HA demonstrates better scaffold properties, together with higher biocompatibility and cell viability in comparison with the NC-Alg scaffolds. Thus, the use of MSCs containing NC-Alg based scaffolds may become a feasible tissue engineering approach for regenerative medicine., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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118. GSE4-loaded nanoparticles a potential therapy for lung fibrosis that enhances pneumocyte growth, reduces apoptosis and DNA damage.
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Pintado-Berninches L, Montes-Worboys A, Manguan-García C, Arias-Salgado EG, Serrano A, Fernandez-Varas B, Guerrero-López R, Iarriccio L, Planas L, Guenechea G, Egusquiaguirre SP, Hernandez RM, Igartua M, Luis Pedraz J, Cortijo J, Sastre L, Molina-Molina M, and Perona R
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- Alveolar Epithelial Cells drug effects, Alveolar Epithelial Cells metabolism, Collagen drug effects, Collagen metabolism, Humans, Lung metabolism, Oxidative Stress drug effects, Peptides pharmacology, Apoptosis drug effects, Bleomycin pharmacology, DNA Damage drug effects, Lung drug effects, Nanoparticles therapeutic use
- Abstract
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., (© 2021 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)
- Published
- 2021
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119. Type 1 Diabetes Mellitus reversal via implantation of magnetically purified microencapsulated pseudoislets.
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Espona-Noguera A, Etxebarria-Elezgarai J, Saenz Del Burgo L, Cañibano-Hernández A, Gurruchaga H, Blanco FJ, Orive G, Hernández RM, Benito-Lopez F, Ciriza J, Basabe-Desmonts L, and Pedraz JL
- Subjects
- Alginates chemistry, Animals, Blood Glucose metabolism, Capsules, Drug Compounding, Magnetics, Male, Polylysine analogs & derivatives, Polylysine chemistry, Rats, Rats, Wistar, Treatment Outcome, Diabetes Mellitus, Experimental therapy, Diabetes Mellitus, Type 1 therapy, Islets of Langerhans Transplantation methods, Lab-On-A-Chip Devices
- Abstract
Microencapsulation of pancreatic islets for the treatment of Type I Diabetes Mellitus (T1DM) generates a high quantity of empty microcapsules, resulting in high therapeutic graft volumes that can enhance the host's immune response. We report a 3D printed microfluidic magnetic sorting device for microcapsules purification with the objective to reduce the number of empty microcapsules prior transplantation. In this study, INS1E pseudoislets were microencapsulated within alginate (A) and alginate-poly-L-lysine-alginate (APA) microcapsules and purified through the microfluidic device. APA microcapsules demonstrated higher mechanical integrity and stability than A microcapsules, showing better pseudoislets viability and biological function. Importantly, we obtained a reduction of the graft volume of 77.5% for A microcapsules and 78.6% for APA microcapsules. After subcutaneous implantation of induced diabetic Wistar rats with magnetically purified APA microencapsulated pseudoislets, blood glucose levels were restored into normoglycemia (<200 mg/dL) for almost 17 weeks. In conclusion, our described microfluidic magnetic sorting device represents a great alternative approach for the graft volume reduction of microencapsulated pseudoislets and its application in T1DM disease., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2019
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120. Low molecular-weight hyaluronan as a cryoprotectant for the storage of microencapsulated cells.
- Author
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Gurruchaga H, Saenz Del Burgo L, Orive G, Hernandez RM, Ciriza J, and Pedraz JL
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- Apoptosis drug effects, Cell Line, Cell Survival drug effects, Drug Compounding, Humans, Hyaluronan Receptors metabolism, Molecular Weight, Cryopreservation, Cryoprotective Agents pharmacology, Hyaluronic Acid pharmacology
- Abstract
The low-temperature storage of therapeutic cell-based products plays a crucial role in their clinical translation for the treatment of diverse diseases. Although dimethylsulfoxide (DMSO) is the most successful cryoprotectant in slow freezing of microencapsulated cells, it has shown adverse effects after cryopreserved cell-based products implantation. Therefore, the search of alternative non-toxic cryoprotectants for encapsulated cells is continuously investigated to move from bench to the clinic. In this work, we investigated the low molecular-weight hyaluronan (low MW-HA), a natural non-toxic and non-sulfated glycosaminoglycan, as an alternative non-permeant cryoprotectant for the slow freezing cryopreservation of encapsulated cells. Cryopreservation with low MW-HA provided similar metabolic activity, cell dead and early apoptotic cell percentage and membrane integrity after thawing, than encapsulated cells stored with either DMSO 10% or Cryostor 10. However, the beneficial outcomes with low MW-HA were not comparable to DMSO with some encapsulated cell types, such as the human insulin secreting cell line, 1.1B4, maybe explained by the different expression of the CD44 surface receptor. Altogether, we can conclude that low MW-HA represents a non-toxic natural alternative cryoprotectant to DMSO for the cryopreservation of encapsulated cells., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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121. Advances in the slow freezing cryopreservation of microencapsulated cells.
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Gurruchaga H, Saenz Del Burgo L, Hernandez RM, Orive G, Selden C, Fuller B, Ciriza J, and Pedraz JL
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- Alginates chemistry, Animals, Cold Temperature, Drug Delivery Systems methods, Freezing, Humans, Regenerative Medicine methods, Cryopreservation methods, Drug Compounding methods
- Abstract
Over the past few decades, the use of cell microencapsulation technology has been promoted for a wide range of applications as sustained drug delivery systems or as cells containing biosystems for regenerative medicine. However, difficulty in their preservation and storage has limited their availability to healthcare centers. Because the preservation in cryogenic temperatures poses many biological and biophysical challenges and that the technology has not been well understood, the slow cooling cryopreservation, which is the most used technique worldwide, has not given full measure of its full potential application yet. This review will discuss the different steps that should be understood and taken into account to preserve microencapsulated cells by slow freezing in a successful and simple manner. Moreover, it will review the slow freezing preservation of alginate-based microencapsulated cells and discuss some recommendations that the research community may pursue to optimize the preservation of microencapsulated cells, enabling the therapy translate from bench to the clinic., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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122. Engineering a Clinically Translatable Bioartificial Pancreas to Treat Type I Diabetes.
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Orive G, Emerich D, Khademhosseini A, Matsumoto S, Hernández RM, Pedraz JL, Desai T, Calafiore R, and de Vos P
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- Animals, Clinical Trials as Topic, Humans, Insulin-Secreting Cells chemistry, Insulin-Secreting Cells transplantation, Materials Testing, Membranes, Artificial, Models, Animal, Bioartificial Organs, Diabetes Mellitus, Experimental therapy, Diabetes Mellitus, Type 1 therapy, Pancreas, Artificial, Tissue Engineering
- Abstract
Encapsulating, or immunoisolating, insulin-secreting cells within implantable, semipermeable membranes is an emerging treatment for type 1 diabetes. This approach can eliminate the need for immunosuppressive drug treatments to prevent transplant rejection and overcome the shortage of donor tissues by utilizing cells derived from allogeneic or xenogeneic sources. Encapsulation device designs are being optimized alongside the development of clinically viable, replenishable, insulin-producing stem cells, for the first time creating the possibility of widespread therapeutic use of this technology. Here, we highlight the status of the most advanced and widely explored implementations of cell encapsulation with an eye toward translating the potential of this technological approach to medical reality., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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123. Biologically active and biomimetic dual gelatin scaffolds for tissue engineering.
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Sánchez P, Pedraz JL, and Orive G
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- Animals, Biomimetic Materials pharmacology, Cell Adhesion drug effects, Cell Line, Gelatin pharmacology, Hedgehog Proteins metabolism, Materials Testing, Mechanical Phenomena, Mesenchymal Stem Cells cytology, Mesenchymal Stem Cells drug effects, Mesenchymal Stem Cells metabolism, Mice, Vascular Endothelial Growth Factor A metabolism, Biomimetic Materials chemistry, Gelatin chemistry, Tissue Engineering, Tissue Scaffolds chemistry
- Abstract
We have designed, developed and optimized Genipin cross-linked 3D gelatin scaffolds that were biologically active and biomimetic, show a dual activity both for growth factor and cell delivery. Type B gelatin powder was dissolved in DI water. 100mg of genipin was dissolved in 10ml of DI water. Three genipin concentrations were prepared: 0.1%, 0.2% and 0.3% (w/v). Solutions were mixed at 40°C and under stirring and then left crosslinking for 72h. Scaffolds were obtained by punching 8 mm-cylinders into ethanol 70% solution for 10min and then freeze-drying. Scaffolds were biologically, biomechanically and morphologically evaluated. Cell adhesion and morphology of D1-Mesenchymal stem cells (MSCs) and L-929 fibroblast was studied. Vascular endothelial grwoth factor (VEGF) and Sonic hedgehog (SHH) were used as model proteins. Swelling ratio increased and younǵs module decreased along with the concentration of genipin. All scaffolds were biocompatible according to the toxicity test. MSC and L-929 cell adhesion improved in 0.2% of genipin, obtaining better results with MSCs. VEGF and SHH were released from the gels. This preliminary study suggest that the biologically active and dual gelatin scaffolds may be used for tissue engineering approaches like bone regeneration., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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124. Use of Flow Focusing Technique for Microencapsulation of Myoblasts.
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Ciriza J, Saenz del Burgo L, Hernández RM, Orive G, and Pedraz JL
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- Animals, Capsules chemistry, Cell Survival, Drug Compounding methods, Drug Delivery Systems, Equipment Design, Erythropoietin administration & dosage, Glucuronic Acid chemistry, Hexuronic Acids chemistry, Humans, Pressure, Alginates chemistry, Cells, Immobilized cytology, Drug Compounding instrumentation, Myoblasts cytology
- Abstract
Alginate cell microencapsulation implies the immobilization of cells within a polymeric membrane that allows the bidirectional diffusion of nutrients and oxygen inside the microcapsules and the release of waste and therapeutic molecules outside them. This technology has been applied to several cell types and it has been extensively described with pancreatic islets. However, other cells such as myoblasts are being currently studied and showing high interest. Moreover, different systems and approaches have been developed for cell encapsulation such as electrostatic extrusion and Flow focusing technology. When Flow focusing technology is applied for myoblast encapsulation, several factors should be considered, such as the pressure, the flow of the system, or the diameter size of the nebulizer, which will determine the final diameter size and shape of the microcapsules containing the myoblasts. Finally, viability of encapsulated myoblasts needs to be assessed before further studies are performed.
- Published
- 2017
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125. Microencapsulated Cells for Cancer Therapy.
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Saenz del Burgo L, Ciriza J, Hernández RM, Orive G, and Pedraz JL
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- Animals, Cell Count, Cell Line, Cell Survival, Cell- and Tissue-Based Therapy methods, Cells, Immobilized metabolism, Cells, Immobilized transplantation, Drug Compounding instrumentation, Drug Compounding methods, Drug Delivery Systems, Equipment Design, Humans, Hybridomas metabolism, Hybridomas transplantation, Polylysine chemistry, Static Electricity, Alginates chemistry, Capsules chemistry, Cells, Immobilized cytology, Hybridomas cytology, Neoplasms therapy, Polylysine analogs & derivatives
- Abstract
The microencapsulation of different types of cells that are able to produce therapeutic factors is being investigated for the treatment of several human diseases. Most efforts are focused on chronic and degenerative diseases as this strategy could become an alternative to some commonly used parenteral treatments that need to be repeatedly administered. But, this approach has also been investigated in the field of oncology with the aim of providing immunomodulatory antibodies that are able to enhance the patient's inherent immune response against the tumor. These kind of treatments would provide the patient with the therapeutic drug produced in situ, de novo, and in a sustained way, making the therapy more comfortable.Although different devices are nowadays available to produce cell-enclosing alginate-microcapsules, here, we describe the most important steps and advices in order to fabricate alginate-poly-L-lysine-alginate microcapsules containing hybridoma cells for cancer management using an electrostatic bead generator, and how to evaluate the viability of those cells over the time.
- Published
- 2017
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126. Killing effect of nanoencapsulated colistin sulfate on Pseudomonas aeruginosa from cystic fibrosis patients.
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Sans-Serramitjana E, Fusté E, Martínez-Garriga B, Merlos A, Pastor M, Pedraz JL, Esquisabel A, Bachiller D, Vinuesa T, and Viñas M
- Subjects
- Adult, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents pharmacokinetics, Child, Drug Delivery Systems methods, Drug Monitoring methods, Drug Resistance, Bacterial drug effects, Female, Humans, Male, Middle Aged, Nanoparticles administration & dosage, Outcome Assessment, Health Care, Respiratory System microbiology, Spain epidemiology, Biofilms drug effects, Colistin administration & dosage, Colistin pharmacokinetics, Cystic Fibrosis diagnosis, Cystic Fibrosis epidemiology, Cystic Fibrosis microbiology, Cystic Fibrosis therapy, Pseudomonas Infections diagnosis, Pseudomonas Infections drug therapy, Pseudomonas aeruginosa drug effects, Pseudomonas aeruginosa isolation & purification, Pseudomonas aeruginosa physiology, Respiratory Tract Infections diagnosis, Respiratory Tract Infections drug therapy, Respiratory Tract Infections microbiology
- Abstract
Pseudomonas aeruginosa frequently infects the respiratory tract of cystic fibrosis (CF) patients. Multidrug-resistant phenotypes and high capacity to form stable biofilms are common. Recent studies have described the emergence of colistin-resistant isolates in CF patients treated with long-term inhaled colistin. The use of nanoparticles containing antimicrobials can contribute to overcome drug resistance mechanisms. The aim of this study was to explore antimicrobial activity of nanoencapsulated colistin (SLN-NLC) versus free colistin against P. aeruginosa clinical isolates from CF patients and to investigate their efficacy in biofilm eradication. Susceptibility of planktonic bacteria to antimicrobials was examined by using the broth microdilution method and growth curve assay. Minimal biofilm eradication concentration (MBEC) and biofilm prevention concentration (BPC) were determined to assess antimicrobial susceptibility of sessile bacteria. We used atomic force microscopy (AFM) to visualize treated and untreated biofilms and to determine surface roughness and other relevant parameters. Colistin nanoparticles had the same antimicrobial activity as free drug against planktonic bacteria. However, nanoencapsulated colistin was much more efficient in the eradication of biofilms than free colistin. Thus, these formulations have to be considered as a good alternative therapeutic option to treat P. aeruginosa infections., (Copyright © 2015 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
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127. Potent anticholinesterasic and neuroprotective pyranotacrines as inhibitors of beta-amyloid aggregation, oxidative stress and tau-phosphorylation for Alzheimer's disease.
- Author
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García-Font N, Hayour H, Belfaitah A, Pedraz J, Moraleda I, Iriepa I, Bouraiou A, Chioua M, Marco-Contelles J, and Oset-Gasque MJ
- Subjects
- Alzheimer Disease drug therapy, Animals, Cholinesterase Inhibitors chemistry, Cholinesterase Inhibitors therapeutic use, Drug Design, Electrophorus, Hep G2 Cells, Humans, Neuroprotective Agents chemistry, Neuroprotective Agents therapeutic use, Oligomycins toxicity, Phosphorylation drug effects, Protein Aggregates drug effects, Rotenone toxicity, Tacrine chemistry, Tacrine therapeutic use, Alzheimer Disease metabolism, Amyloid beta-Peptides chemistry, Cholinesterase Inhibitors pharmacology, Neuroprotective Agents pharmacology, Oxidative Stress drug effects, Peptide Fragments chemistry, Tacrine pharmacology, tau Proteins chemistry
- Abstract
Herein we describe the synthesis and in vitro biological evaluation of thirteen new, racemic, diversely functionalized 2-chloroquinolin-3-yl substituted PyranoTacrines (PTs) as multipotent tacrine analogues for Alzheimer's disease (AD) therapy. Among these compounds, 1-(5-amino-4-(2-chloro-7-methoxyquinolin-3-yl)-2-methyl-6,7,8,9-tetrahydro-4H-pyrano [2,3-b]quinolin-3-yl)éthanone (9) and ethyl 5-amino-4-(2-chloroquinolin-3-yl)-2-methyl-6,7,8,9-tetrahydro-4H-pyrano[2,3-b]quinoline-3-carboxylate (4) were found to be non-neurotoxic agents in human neuroblastoma SHSY5Y cells. Compounds 9 (IC50 = 0.47 ± 0.13 μM) and 4 (IC50 = 0.48 ± 0.05 μM) are potent, mixed-type (9: Ki = 0.0142 ± 0.003 μM), and selective EeAChE inhibitors, binding at the both catalytic and peripheral anionic site of the enzyme. Compounds 9 and 4 are neuroprotective agents at low μM concentrations upon decreased viability of SHSY5Y cells induced by oxidative stress, and stimulators of GSK3β-dependent tau phosphorylation. In addition, molecules 9 and 4 effectively counteract Aβ-aggregation on exposure to Aβ1-40, as well as Aβ1-40 aggregation-dependent tau-oligomerization and phosphorylation in (396)Ser, which could be ascribed to the anti-aggregating properties shown in vitro. Thus, a new family of tacrine analogues, whose potent AChEI activity is linked to both their Aβ-aggregating and tau-phosphorylation inhibitory capacities, has been discovered for the potential treatment of AD., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)
- Published
- 2016
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128. The influence of the polar head-group of synthetic cationic lipids on the transfection efficiency mediated by niosomes in rat retina and brain.
- Author
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Ojeda E, Puras G, Agirre M, Zarate J, Grijalvo S, Eritja R, Martinez-Navarrete G, Soto-Sánchez C, Diaz-Tahoces A, Aviles-Trigueros M, Fernández E, and Pedraz JL
- Subjects
- Animals, Cations, Cell Line, Cells, Cultured, DNA administration & dosage, DNA genetics, Drug Stability, Genes, Reporter, Genetic Vectors administration & dosage, Green Fluorescent Proteins biosynthesis, Green Fluorescent Proteins genetics, HEK293 Cells, Hippocampus cytology, Hippocampus embryology, Humans, Hydrophobic and Hydrophilic Interactions, Injections, Intraocular, Intravitreal Injections, Liposomes administration & dosage, Male, Neurons cytology, Propanolamines administration & dosage, Propanolamines chemical synthesis, Rats, Rats, Sprague-Dawley, Retinal Pigment Epithelium cytology, Urea administration & dosage, Urea chemical synthesis, Urea pharmacology, Cerebral Cortex metabolism, Genetic Vectors chemistry, Liposomes chemistry, Propanolamines pharmacology, Retina metabolism, Transfection methods, Urea analogs & derivatives
- Abstract
The development of novel non-viral delivery vehicles is essential in the search of more efficient strategies for retina and brain diseases. Herein, optimized niosome formulations prepared by oil-in water (o/w) and film-hydration techniques were characterized in terms of size, PDI, zeta potential, morphology and stability. Three ionizable glycerol-based cationic lipids containing a primary amine group (lipid 1), a triglycine group (lipid 2) and a dimethylamino ethyl pendent group (lipid 3) as polar head-groups were part of such niosomes. Upon the addition of pCMS-EGFP plasmid, nioplexes were obtained at different cationic lipid/DNA ratios (w/w). The resultant nioplexes were further physicochemically characterized and evaluated to condense, release and protect the DNA against enzymatic digestion. In vitro experiments were performed to evaluate transfection efficiency and cell viability in HEK-293, ARPE-19 and PECC cells. Interestingly, niosome formulations based on lipid 3 showed better transfection efficiencies in ARPE-19 and PECC cells than the rest of cationic lipids showed in this study. In vivo experiments in rat retina after intravitreal and subretinal injections together with in rat brain after cerebral cortex administration showed promising transfection efficiencies when niosome formulations based on lipid 3 were used. These results provide new insights for the development of non-viral vectors based on cationic lipids and their applications for efficient delivery of genetic material to the retina and brain., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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129. Graphene oxide increases the viability of C2C12 myoblasts microencapsulated in alginate.
- Author
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Ciriza J, Saenz del Burgo L, Virumbrales-Muñoz M, Ochoa I, Fernandez LJ, Orive G, Hernandez RM, and Pedraz JL
- Subjects
- Alginates chemistry, Alginates pharmacology, Animals, Apoptosis, Cell Line, Cell Survival drug effects, Drug Compounding, Erythropoietin metabolism, Glucuronic Acid chemistry, Glucuronic Acid pharmacology, Graphite pharmacology, Hexuronic Acids chemistry, Hexuronic Acids pharmacology, L-Lactate Dehydrogenase metabolism, Mice, Myoblasts drug effects, Myoblasts metabolism, Oxides pharmacology, Drug Delivery Systems, Graphite chemistry, Oxides chemistry
- Abstract
Cell microencapsulation represents a great promise for long-term drug delivery, but still several challenges need to be overcome before its translation into the clinic, such as the long term cell survival inside the capsules. On this regard, graphene oxide has shown to promote proliferation of different cell types either in two or three dimensions. Therefore, we planned to combine graphene oxide with the cell microencapsulation technology. We first studied the effect of this material on the stability of the capsules and next we analyzed the biocompatibility of this chemical compound with erythropoietin secreting C2C12 myoblasts within the microcapsule matrix. We produced 160 μm-diameter alginate microcapsules with increasing concentrations of graphene oxide and did not find modifications on the physicochemical parameters of traditional alginate microcapsules. Moreover, we observed that the viability of encapsulated cells within alginate microcapsules containing specific graphene oxide concentrations was enhanced. These results provide a relevant step for the future clinical application of graphene oxide on cell microencapsulation., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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130. Development and in vitro evaluation of lipid nanoparticle-based dressings for topical treatment of chronic wounds.
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Gainza G, Chu WS, Guy RH, Pedraz JL, Hernandez RM, Delgado-Charro B, and Igartua M
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- Administration, Topical, Animals, Bandages, Chemistry, Pharmaceutical methods, Delayed-Action Preparations administration & dosage, Delayed-Action Preparations chemistry, Epidermal Growth Factor administration & dosage, Epidermal Growth Factor chemistry, Female, Fibrin metabolism, Hydrogels administration & dosage, Hydrogels chemistry, Lipids administration & dosage, Nanoparticles administration & dosage, Nanostructures administration & dosage, Nanostructures chemistry, Skin Absorption, Swine, Wounds and Injuries metabolism, Lipids chemistry, Nanoparticles chemistry, Skin metabolism, Wounds and Injuries drug therapy
- Abstract
This research addresses the development and in vitro evaluation of lipid nanoparticle (NP)-based dressings to optimize the delivery of human recombinant epidermal growth factor (rhEGF) for the topical treatment of chronic wounds. The systems investigated were rhEGF-loaded solid lipid nanoparticles (rhEGF-SLN) and rhEGF-loaded nanostructured lipid carriers (rhEGF-NLC) formulated in wound dressings comprising either semi-solid hydrogels or fibrin-based solid scaffolds. Following detailed characterisation of the NP, in vitro diffusion cell experiments (coupled with dermatopharmacokinetic measurements), together with confocal microscopic imaging, conducted on both intact skin samples, and those from which the barrier (the stratum corneum) had been removed, revealed that (a) the particles remained essentially superficially located for at least up to 48h post-application, (b) rhEGF released on the surface of intact skin was unable to penetrate to the deeper, viable layers, and (c) sustained release of growth factor from the NP "drug reservoirs" into barrier-compromised skin was observed. There were no significant differences between the in vitro performance of rhEGF-SLN and rhEGF-NLC, irrespective of the formulation employed. It is concluded that, because of their potentially longer-term stability, the fibrin-based scaffolds may be the most suitable approach to formulate rhEGF-loaded lipid nanoparticles., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2015
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131. Enhanced Hippocampal Neurogenesis in APP/Ps1 Mouse Model of Alzheimer's Disease After Implantation of VEGF-loaded PLGA Nanospheres.
- Author
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Herran E, Perez-Gonzalez R, Igartua M, Pedraz JL, Carro E, and Hernandez RM
- Subjects
- Alzheimer Disease pathology, Alzheimer Disease physiopathology, Alzheimer Disease surgery, Amyloid beta-Protein Precursor genetics, Amyloid beta-Protein Precursor metabolism, Animals, Biodegradable Plastics chemistry, Cell Proliferation drug effects, Cell Proliferation physiology, Cells, Cultured, Cerebral Cortex pathology, Cerebral Cortex physiopathology, Cerebral Cortex surgery, Disease Models, Animal, Doublecortin Protein, Drug Carriers chemistry, Drug Implants chemistry, Female, Hippocampus drug effects, Hippocampus pathology, Hippocampus physiopathology, Humans, Lactic Acid chemistry, Mice, Transgenic, Nanospheres chemistry, Neurogenesis physiology, Polyglycolic Acid chemistry, Polylactic Acid-Polyglycolic Acid Copolymer, Presenilin-1 genetics, Presenilin-1 metabolism, Rats, Wistar, Alzheimer Disease drug therapy, Cerebral Cortex drug effects, Neurogenesis drug effects, Neuroprotective Agents administration & dosage, Vascular Endothelial Growth Factor A administration & dosage
- Abstract
During adult life, hippocampus is an important brain region involved in neurogenesis. The generation and cell death of newly generated neuronal cells in this region have critical roles in brain maintenance and alterations in these processes are seen in Alzheimer's disease (AD). For the purpose of carrying out a neuroregenerative strategy, we propose a novel approach based on the encapsulation of vascular endothelial growth factor (VEGF) in poly (lactic co-glycolic acid) (PLGA) biodegradable nanospheres (NS) administered by craniotomy to stimulate the proliferation of neuronal precursors in a transgenic mouse model of AD. VEGF loaded nanospheres were prepared by double emulsion solvent evaporation technique, obtaining 200 nm nanospheres with a biphasic release profile. After demonstrating their efficacy in the proliferation and differentiation of neuronal cell cultures, in vivo studies were carried out. 3 months after VEGF-NS were implanted directly into the cerebral cortex of APP/Ps1 mice, the determination of BrdU(+) cells in the whole hippocampal region and specifically in the dentate gyrus, demonstrated a significantly enhanced cellular proliferation in VEGF-NS treated group. These results were also confirmed showing an increased number of DCX(+) and NeuN(+) cells. Hence, PLGA-VEGF nanospheres may be a potential strategy to modulate proliferative neuronal progenitors in the hippocampal region, and therefore, provide new insight for future therapeutic approaches in AD.
- Published
- 2015
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132. Advanced nanovehicles for cancer management.
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Saenz del Burgo L, Pedraz JL, and Orive G
- Subjects
- Animals, Humans, Immunotherapy, Magnetic Phenomena, Neoplasms drug therapy, Nucleic Acids administration & dosage, Photochemotherapy, Antineoplastic Agents administration & dosage, Drug Carriers administration & dosage, Nanoparticles administration & dosage, Neoplasms therapy
- Abstract
Over the past decade, together with the improvement of traditional cancer treatments, conveniently designed (with respect to their size, shape, main material, and coating) and specifically targeted nanovehicles have been developed. Nano-sized carriers can be functionalized to recognize key structures expressed in cancer cells and/or their surrounding tissues. Recently, some more complex systems have been developed that exploit the human body's own communication systems to enhance their efficacy. Some of the newest nanoparticles have the capacity to not only serve as drug delivery systems for a myriad of molecules, but also operate as direct cancer treatment agents themselves, such as in thermal therapies. In this review, we highlight the most recent advances in nanotechnology for treating cancer and address some of the challenges and opportunities in the field., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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133. Novel drug delivery systems for releasing growth factors to the CNS: focus on Alzheimer's and Parkinson's diseases.
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Herran E, Igartua M, Pedraz JL, and Hernandez RM
- Subjects
- Alzheimer Disease therapy, Animals, Humans, Intercellular Signaling Peptides and Proteins therapeutic use, Parkinson Disease therapy, Alzheimer Disease metabolism, Central Nervous System metabolism, Drug Delivery Systems, Intercellular Signaling Peptides and Proteins administration & dosage, Intercellular Signaling Peptides and Proteins pharmacokinetics, Parkinson Disease metabolism
- Abstract
Alzheimer's disease (AD) and Parkinson's disease (PD) represent the most common neurodegenerative disorders and affect more than 35 million people. Due to the limited effectiveness of available treatments in halting the neurodegenerative process, new therapies, such therapies based on growth factors (GFs), have been investigated. Nevertheless, the efficacies of these new treatments depend not only on the application of neurotrophins but also on the approaches used to deliver these proteins such that they can reach the brain. This review summarises the most widely used drug delivery systems (DDSs) for releasing GFs as possible treatments for AD and PD.
- Published
- 2014
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134. The state-of-the-art of approved and under-development cholera vaccines.
- Author
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Pastor M, Pedraz JL, and Esquisabel A
- Subjects
- Cholera therapy, Cholera transmission, Drug Delivery Systems, Humans, Vaccines, Attenuated pharmacology, Vaccines, Inactivated pharmacology, Vibrio cholerae pathogenicity, Cholera Vaccines administration & dosage, Cholera Vaccines pharmacology
- Abstract
Cholera remains a huge public health problem. Although in 1894, the first cholera vaccination was reported, an ideal vaccine that meets all the requirements of the WHO has not yet been produced. Among the different approaches used for cholera vaccination, attenuated vaccines represent a major category; these vaccines are beneficial in being able to induce a strong protective response after a single administration. However, they have possible negative effects on immunocompromised patient populations. Both the licensed CVD103-HgR and other vaccine approaches under development are detailed in this article, such as the Vibrio cholerae 638 vaccine candidate, Peru-15 or CholeraGarde(®) and the VA1.3, VA1.4, IEM 108 VCUSM2 and CVD 112 vaccine candidates. In another strategy, killed V. cholerae vaccines have been developed, including Dukoral(®), mORCAX(®) and Sanchol™. The killed vaccines are already sold, and they have successfully demonstrated their potential to protect populations in endemic areas or after natural disasters. However, these vaccines do not fulfill all the requirements of the WHO because they fail to confer long-term protection, are not suitable for children under two years, require more than a single dose and require a distribution chain with cold storage. Lastly, other vaccine strategies under development are summarized in this review. Among these strategies, vaccine candidates based on alternative drug delivery systems that have been reported lately in the literature are discussed, such as microparticles, proteoliposomes, LPS subunits, DNA vaccines and rice seeds containing toxin subunits. Preliminary results reported by many groups working on alternative delivery systems for cholera vaccines demonstrate the importance of new technologies in addressing old problems such as cholera. Although a fully ideal vaccine has not yet been designed, promising steps have been reported in the literature resulting in hope for the fight against cholera., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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135. An approach to a cold chain free oral cholera vaccine: in vitro and in vivo characterization of Vibrio cholerae gastro-resistant microparticles.
- Author
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Pastor M, Esquisabel A, Talavera A, Año G, Fernández S, Cedré B, Infante JF, Callicó A, and Pedraz JL
- Subjects
- Acrylic Resins, Administration, Oral, Alginates administration & dosage, Animals, Antibodies, Bacterial blood, Drug Stability, Drug Storage, Female, Glucuronic Acid administration & dosage, Glucuronic Acid chemistry, Hexuronic Acids administration & dosage, Hexuronic Acids chemistry, Methacrylates administration & dosage, Particle Size, Polymers administration & dosage, Polyvinyls administration & dosage, Polyvinyls chemistry, Rats, Rats, Sprague-Dawley, Refrigeration, Alginates chemistry, Cholera Vaccines, Methacrylates chemistry, Polymers chemistry, Vaccines, Inactivated, Vibrio cholerae
- Abstract
The present work describes the formulation of Eudragit(®) L30 D-55 microparticles (MP) alone or with mucoadhesive agents, alginate or Carbopol(®), as an approach for the development of an oral cholera vaccine. In the first part, a spray drying technique was optimized for microparticle elaboration, obtaining a microparticle size ranging from 7 to 9 μm with high encapsulation efficiencies. Moreover, gastro resistant properties and Vibrio cholerae (VC) antigenicity were maintained, but for Eudragit(®)-Carbopol(®) microparticles which showed low antigenicity values, ≈25%. Next, a stability study was performed following ICH Q1 A (R2) guidelines, i.e. 25°C-60% relative humidity (RH) for 12 months, and 30°C-65% RH and 40°C-75% RH for 6 months. Upon storage, microparticle size changed slightly, 1 μm for Eudragit(®)-alginate MPs and 0.36 μm for Eudragit(®)MP. However, gastro resistance and antigenicity values were kept in an acceptance range. In the third stage of this work, in vivo experiments were performed. The immune response evoked was measured by means of vibriocidal titer quantification, observing that Eudragit(®)-alginate MPs were able to induce stronger immune responses, comparable to the free VC. Therefore, microencapsulation of VC by spray drying could be proposed as an approach to a cold chain free and effective oral cholera vaccine., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
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136. Low molecular weight oligochitosans for non-viral retinal gene therapy.
- Author
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Puras G, Zarate J, Aceves M, Murua A, Díaz AR, Avilés-Triguero M, Fernández E, and Pedraz JL
- Subjects
- Animals, Cell Line, Chitin administration & dosage, Chitosan, Gene Transfer Techniques, Genetic Therapy methods, HEK293 Cells, Humans, Male, Molecular Weight, Oligosaccharides, Particle Size, Polymers metabolism, Rats, Rats, Sprague-Dawley, Transfection methods, Chitin analogs & derivatives, DNA administration & dosage, Retina metabolism
- Abstract
Ultrapure oligochitosans have recently been evaluated as a promising tool for corneal gene therapy; however, there are no reports regarding the potential use of this polymer in other ocular tissues. We have prepared and characterized at pH 7.1 oligochitosan/pCMS-EGFP polyplexes to evaluate the transfection efficiency in rat retinas after subretinal and intravitreal administration. Polyplexes were characterized in terms of shape, size, surface charge, DNA condensation, and transfection efficiency in HEK-293 and ARPE-19 culture cells. Polyplexes were positively charged, around 10 mV, and size oscillated between 256.5 ± 56 and 67.3 ± 0.44 nm, depending on the nitrogenous/phosphate ratio. Polyplexes efficiently protected the plasmid against enzymatic digestion. A drastic increase in transfection efficiency was observed when pH slightly decreased from 7.4 to 7.1 in both HEK-293 (from 19.1% to 51.5%) and ARPE-19 (from 2.0% to 36.5%) cells (data normalized to Lipofectamine™ 2000). In rat retinas, subretinal administrations transfected cells mainly in the RPE layer, whereas intravitreal injections transfected cells in the inner nuclear and plexiform layers of the retina and mainly in the ganglion cell layer. This study establishes the base for future treatments of genetic retinal disorders with low molecular weight oligochitosan polyplexes., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2013
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137. Oligochitosan polyplexes as carriers for retinal gene delivery.
- Author
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Puras G, Zarate J, Díaz-Tahoces A, Avilés-Trigueros M, Fernández E, and Pedraz JL
- Subjects
- Animals, Cell Line, Chitin administration & dosage, Chitin chemistry, Chitosan, DNA chemistry, Genetic Therapy methods, Genetic Vectors, Green Fluorescent Proteins chemistry, HEK293 Cells, Humans, Male, Oligosaccharides, Plasmids, Rats, Rats, Sprague-Dawley, Chitin analogs & derivatives, DNA administration & dosage, Green Fluorescent Proteins genetics, Retina metabolism
- Abstract
Non-viral gene therapy represents a promising approach for the treatment of retinal diseases. However, the lack of an efficient carrier hampers the implementation of this therapy. In this study, we evaluated low molecular weight ultrapure oligochitosans for the delivery of the pCMS-EGFP plasmid into the rat retina cells after subretinal and intravitreal administrations. Polyplexes were technologically characterized. Resulting polyplexes based on ultrapure oligochitosans were slightly spherical, protected the plasmid against enzymatic digestion, and their charge and size values ranged from 8 to 14 millivolts and from 150 to 69 nm respectively depending on the N/P ratio. In HEK-293 cultured cells, transfection efficiency significantly increased from 12% to 30% when pH decreased from 7.4 to 7.1 (data normalized to Lipofectamine™ 2000). However, no significant transfection was detected in ARPE-19 cultured cells. Subretinal administrations transfected mainly the pigmented cells of the retinal pigment epithelium and the light sensitive photoreceptor cells, whereas intravitreal injections transfected cells in the ganglion cell layer, blood vessels in the inner layers of the retina and photoreceptors. These results support the potential use of oligochitosans for delivering genetic material into retinal cells in vivo., (Copyright © 2012. Published by Elsevier B.V.)
- Published
- 2013
- Full Text
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138. Optimization of 100 μm alginate-poly-L-lysine-alginate capsules for intravitreous administration.
- Author
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Santos E, Orive G, Calvo A, Catena R, Fernández-Robredo P, Layana AG, Hernández RM, and Pedraz JL
- Subjects
- Animals, Cell Line, Genes, Reporter genetics, Green Fluorescent Proteins genetics, Intravitreal Injections, Luciferases genetics, Mice, Mice, Inbred C3H, Polylysine administration & dosage, Rats, Rats, Wistar, Thymidine Kinase genetics, Transfection, Vascular Endothelial Growth Factor Receptor-2 genetics, Vascular Endothelial Growth Factor Receptor-2 metabolism, Alginates administration & dosage, Capsules administration & dosage, Polylysine analogs & derivatives
- Abstract
The field of cell microencapsulation is advancing rapidly. Particle size plays a critical role in terms of biocompatibility and limits decisively its applicability. Producing reduced size microcapsules involves broadening the possibilities to employ this technology in the treatment of many disorders. Nervous system diseases (NSD) represent a clear example of that. This work describes the feasibility of reducing the size of alginate-poly-L-lysine-alginate (APA) microcapsules up to 100 μm in a highly monodisperse way using the novel Flow Focusing technique. C(2)C(12) myoblasts genetically engineered to express the triple reporter gene thymidine kinase-green fluorescent protein-luciferase (TGL) and secrete vascular endothelial growth factor soluble receptor 2 (VEGFR2, also known as KDR) were encapsulated for further characterization. Resulting new particles were assayed in vitro to explore whether their functionality might be affected due to the physicochemical changes arising from such dramatic size reduction. Not only were negative effects at this level not noticed in terms of cell viability, cell proliferation and KDR secretion, but once again the suitability of APA microcapsules was also reinforced against other microcapsule designs. Furthermore, the fully viable and functional biosystems were successfully administered in the intravitreous space of rats, where the activity of encapsulated cells was monitoring over 3 weeks., (Copyright © 2011. Published by Elsevier B.V.)
- Published
- 2012
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139. Encapsulation of Aβ(1-15) in PLGA microparticles enhances serum antibody response in mice immunized by subcutaneous and intranasal routes.
- Author
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Puras G, Salvador A, Igartua M, Hernández RM, and Pedraz JL
- Subjects
- Administration, Intranasal, Alzheimer Disease immunology, Alzheimer Vaccines administration & dosage, Alzheimer Vaccines therapeutic use, Amyloid beta-Peptides administration & dosage, Amyloid beta-Peptides therapeutic use, Animals, Drug Administration Schedule, Drug Compounding, Enzyme-Linked Immunosorbent Assay, Epitopes, B-Lymphocyte immunology, Epitopes, T-Lymphocyte immunology, Injections, Subcutaneous, Mice, Mice, Inbred BALB C, Microscopy, Electron, Scanning, Particle Size, Peptide Fragments administration & dosage, Peptide Fragments therapeutic use, Polylactic Acid-Polyglycolic Acid Copolymer, Surface Properties, Alzheimer Disease therapy, Alzheimer Vaccines immunology, Amyloid beta-Peptides immunology, Drug Carriers chemistry, Immunoglobulin G blood, Lactic Acid chemistry, Peptide Fragments immunology, Polyglycolic Acid chemistry
- Abstract
The aim of the present work was to develop an easy, safe and effective vaccine in Balb/c mice using the Aβ(1-15) peptide as immunogen entrapped in PLGA microparticles to reduce the risk of an adverse T cell-mediated response. Aβ(1-15,) which contains the N-terminal antibody epitope of the full Aβ(1-42) peptide was encapsulated in PLGA by a modified solvent evaporation/extraction technique using a double emulsion system. Microparticles were characterized in terms of size distribution (1.22±0.28 μm), encapsulation efficiency (75.05±4.17%), surface associated peptide (59.81±0.96%) and "in vitro" release profile. Balb/c mice were immunized by subcutaneous and intranasal routes with three 30 μg doses of the peptide microencapsulated in PLGA. A solution of the peptide alone and an emulsion in the Freund's adjuvant were administered subcutaneously as control groups. Antibody levels elicited against the toxic Aβ(1-40) fraction in the serum of PLGA microparticles treated groups were higher than that of the peptide alone groups. Our initial results indicate that immunotherapy with Aβ(1-15) loaded PLGA microparticles could be a promising approach for the future development of a safe vaccine against Alzheimer's disease., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
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140. Novel extended-release formulation of lovastatin by one-step melt granulation: in vitro and in vivo evaluation.
- Author
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Ochoa L, Igartua M, Hernández RM, Gascón AR, Solinis MA, and Pedraz JL
- Subjects
- Animals, Anticholesteremic Agents blood, Anticholesteremic Agents chemistry, Anticholesteremic Agents pharmacokinetics, Area Under Curve, Delayed-Action Preparations, Dogs, Excipients, Hot Temperature, Hydrophobic and Hydrophilic Interactions, Lovastatin blood, Lovastatin chemistry, Lovastatin pharmacokinetics, Polyethylene Glycols, Solubility, Anticholesteremic Agents administration & dosage, Drug Compounding methods, Lovastatin administration & dosage
- Abstract
The objective of this study was to apply a one-step melt granulation method to develop an extended-release formulation of lovastatin (LOV-ER). We prepared a formulation using PEG 6000 as binder agent in a laboratory scale high-shear mixer. In vitro dissolution studies showed that the release of the drug from the new formulation followed a zero-order kinetic with no differences in the release profile with either the pH media or the agitation rate. The pharmacokinetic of lovastatin and its metabolite lovastatin acid was evaluated after the administration of the new formulation to Beagle dogs in fasted conditions and after a high-fat meal, and compared to the marketed formulation Altoprev®. After the administration of LOV-ER, extended plasma profiles of lovastatin and its active metabolite were achieved in both fasted conditions and after the high-fat meal. Plasma levels of lovastatin and lovastatin acid were always higher when the LOV-ER formulation was administered with the high-fat meal. A high variability in plasma levels and pharmacokinetic parameters was obtained, being this variability higher when the formulation was administered under fasting conditions. Our results suggest that there is an increase in lovastatin bioavailability when the formulation is administered after the high-fat meal. When we compare LOV-ER and Altoprev®, both administered after the high-fat meal, we found significant differences (p<0.05) in C(max) of lovastatin and in AUC(0-∞) and MRT of lovastatin acid. No differences were detected between both formulations in fasting conditions. In this regard, the high-fat meal seems to increase the absorption extent of lovastatin from LOV-ER formulation and to delay the absorption rate of the drug from Altoprev®. In conclusion, we developed a lovastatin formulation that provided extended plasma levels that confirm that one-step melt granulation in high-shear mixer could be an easy and cost-effective technique for extended-release formulation development., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
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141. Design and characterization of calcium alginate microparticles coated with polycations as protein delivery system.
- Author
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Zarate J, Virdis L, Orive G, Igartua M, Hernández RM, and Pedraz JL
- Subjects
- Alginates chemistry, Alginates pharmacology, Chitosan administration & dosage, Chitosan chemistry, Chitosan pharmacology, Coated Materials, Biocompatible chemistry, Coated Materials, Biocompatible pharmacology, DEAE-Dextran administration & dosage, DEAE-Dextran chemistry, DEAE-Dextran pharmacology, Drug Design, Emulsions chemistry, Gels chemistry, Glucuronic Acid administration & dosage, Glucuronic Acid chemistry, Glucuronic Acid pharmacology, Hexuronic Acids administration & dosage, Hexuronic Acids chemistry, Hexuronic Acids pharmacology, Humans, Nanoparticles administration & dosage, Nanoparticles chemistry, Particle Size, Polyamines chemistry, Polyamines pharmacology, Polyelectrolytes, Polylysine administration & dosage, Polylysine analogs & derivatives, Polylysine chemistry, Polylysine pharmacology, Serum Albumin, Bovine chemistry, Serum Albumin, Bovine pharmacology, Alginates administration & dosage, Chemistry, Pharmaceutical methods, Coated Materials, Biocompatible administration & dosage, Drug Delivery Systems methods, Polyamines administration & dosage, Serum Albumin, Bovine administration & dosage
- Abstract
Bovine serum albumin (BSA) loaded calcium alginate microparticles (MPs) produced in this study by a w/o emulsification and external gelation method exhibited spherical and fairly smooth and porous morphology with 1.052 ± 0.057 µm modal particle size. The high permeability of the calcium alginate hydrogel lead to a potent burst effect and too fast protein release. To overcome these problems, MPs were coated with polycations, such as chitosan, poly-L-lysine and DEAE-dextran. Our results demonstrated that coated MPs showed slower release and were able to significantly reduce the release of BSA in the first hour. Therefore, this method can be applied to prepare coated alginate MPs which could be an optimal system for the controlled release of biotherapeutic molecules. Nevertheless, further studies are needed to optimize delivery properties which could provide a sustained release of proteins.
- Published
- 2011
- Full Text
- View/download PDF
142. Familial eruptive generalized lichen planus in a pediatric patient.
- Author
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Pedraz J, Campos-Muñoz L, Conde-Taboada A, Pérez-Álvarez J, and López-Bran E
- Subjects
- Child, Humans, Male, Skin pathology, Lichen Planus genetics, Lichen Planus pathology
- Published
- 2010
- Full Text
- View/download PDF
143. Biomaterial-based technologies for brain anti-cancer therapeutics and imaging.
- Author
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Orive G, Ali OA, Anitua E, Pedraz JL, and Emerich DF
- Subjects
- Animals, Biological Availability, Humans, Immunotherapy, Magnetic Resonance Imaging, Nanoparticles administration & dosage, Biocompatible Materials administration & dosage, Brain Neoplasms diagnosis, Brain Neoplasms drug therapy, Drug Delivery Systems
- Abstract
Treating malignant brain tumors represents one of the most formidable challenges in oncology. Contemporary treatment of brain tumors has been hampered by limited drug delivery across the blood-brain barrier (BBB) to the tumor bed. Biomaterials are playing an increasingly important role in developing more effective brain tumor treatments. In particular, polymer (nano)particles can provide prolonged drug delivery directly to the tumor following direct intracerebral injection, by making them physiochemically able to cross the BBB to the tumor, or by functionalizing the material surface with peptides and ligands allowing the drug-loaded material to be systemically administered but still specifically target the tumor endothelium or tumor cells themselves. Biomaterials can also serve as targeted delivery devices for novel therapies including gene therapy, photodynamic therapy, anti-angiogenic and thermotherapy. Nanoparticles also have the potential to play key roles in the diagnosis and imaging of brain tumors by revolutionizing both preoperative and intraoperative brain tumor detection, allowing early detection of pre-cancerous cells, and providing real-time, longitudinal, non-invasive monitoring/imaging of the effects of treatment. Additional efforts are focused on developing biomaterial systems that are uniquely capable of delivering tumor-associated antigens, immunotherapeutic agents or programming immune cells in situ to identify and facilitate immune-mediated tumor cell killing. The continued translation of current research into clinical practice will rely on solving challenges relating to the pharmacology of nanoparticles but it is envisioned that novel biomaterials will ultimately allow clinicians to target tumors and introduce multiple, pharmaceutically relevant entities for simultaneous targeting, imaging, and therapy in a unique and unprecedented manner., (Copyright 2010 Elsevier B.V. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
144. Therapeutic drug monitoring of mycophenolic acid in patients with psoriasis.
- Author
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Daudén E, Pedraz J, Alvarez-Ruiz S, García-Río I, Sánchez-Peinado C, Oñate MJ, and García-Diez A
- Subjects
- Adult, Aged, Dose-Response Relationship, Drug, Enzyme Inhibitors administration & dosage, Female, Follow-Up Studies, Humans, Male, Middle Aged, Mycophenolic Acid administration & dosage, Psoriasis blood, Psoriasis pathology, Severity of Illness Index, Treatment Outcome, Drug Monitoring methods, Enzyme Inhibitors pharmacokinetics, Mycophenolic Acid pharmacokinetics, Psoriasis drug therapy
- Abstract
Mycophenolate mofetil (MMF) has been shown to be effective in the treatment of psoriasis. MMF is the morpholinoethyl ester of mycophenolic acid (MPA), the active compound. Our objective was to characterize the pharmacokinetic profile of MPA in patients with psoriasis treated with MMF and to examine its correlation with effectiveness and toxicity. Eleven patients with moderate-to-severe chronic plaque psoriasis were treated with oral MMF 30 mg kg-1 daily over a period of 16 weeks. Patients were reviewed at 3, 8 and 16 weeks, checking the Psoriasis Area and Severity Index (PASI) and possible adverse events, and performing MPA C0 (trough) and C1 (1-hour post-dose) plasma levels. The reduction in PASI was statistically significant in all our patients. The drug was well tolerated. There was no significant correlation between C0 and C1 MPA levels and the reduction of PASI, improvement rates of PASI from baseline, weight of the patients and total dosage of MMF. Nevertheless, the highest detected mean levels of MPA C1 were observed in two of the patients with the highest improvement rate of PASI at the end of the study. Although C1 levels do not seem to strongly correlate with the effectiveness of the drug, the finding that the highest detected mean levels of MPA C1 were observed in two of the patients with the highest improvement rate of PASI suggests that the monitoring of C1 could be useful in some individual cases.
- Published
- 2010
- Full Text
- View/download PDF
145. [Psoriatic arthritis and etanercept].
- Author
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Pedraz J and Daudén E
- Subjects
- Controlled Clinical Trials as Topic, Etanercept, Humans, Male, Middle Aged, Arthritis, Psoriatic drug therapy, Immunoglobulin G therapeutic use, Receptors, Tumor Necrosis Factor therapeutic use, Tumor Necrosis Factor-alpha antagonists & inhibitors
- Abstract
Psoriatic arthritis (PA) is a chronic inflammatory condition whose symptoms generally appear after the skin symptoms. Making an early diagnosis and treatment of the disease is of vital importance because of the potential development of mutilating and deforming arthritis. Classical treatments of PA include the use of non-steroid anti-inflammatory drugs, disease-modifying antirheumatic drugs (DMARD) such as methotrexate, sulfasalazine, or gold, and finally, leflunomide. Research on the pathophysiology of psoriasis and of the PA has led to the incorporation of biological treatments, specifically anti-TNF drugs. The three treatments used most in PA are etanercept, infliximab and adalimumab. Of all these, we are going to make a systematic review of the principal studies available on etanercept for the treatment of PA.
- Published
- 2010
- Full Text
- View/download PDF
146. Effect of mycophenolate mofetil therapy on the phenotypic profile of peripheral blood leukocyte populations in psoriatic patients.
- Author
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Daudén E, Pedraz J, Pérez-Gala S, Muñoz C, Vitón M, Onate MJ, and García-Díez A
- Subjects
- Adult, Aged, Antigens analysis, Dermatologic Agents therapeutic use, Female, Humans, Leukocytes immunology, Male, Middle Aged, Mycophenolic Acid pharmacology, Mycophenolic Acid therapeutic use, Severity of Illness Index, Dermatologic Agents pharmacology, Leukocyte Count, Mycophenolic Acid analogs & derivatives, Psoriasis drug therapy
- Published
- 2010
- Full Text
- View/download PDF
147. Polymeric materials and formulation technologies for modified-release tablet development.
- Author
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Zarate J, Igartua M, Hernández RM, and Pedraz JL
- Subjects
- Delayed-Action Preparations, Polymers, Tablets
- Abstract
Over the last years significant advances have been made in the area of drug delivery with the development of modified-release (MR) dosage forms. The present review is divided into two parts, one dealing with technologies for the design of modified-release drug delivery tablets and the other with the use of synthetic and natural polymers that are capable of controlling drug release.
- Published
- 2009
- Full Text
- View/download PDF
148. Peripheral symmetrical gangrene.
- Author
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Pedraz J, Delgado-Jiménez Y, González-De Arriba A, Ríos-Buceta L, Fernández-Herrera J, and García-Diez A
- Subjects
- Extremities, Fatal Outcome, Gangrene etiology, Gangrene pathology, Humans, Male, Middle Aged, Purpura etiology, Disseminated Intravascular Coagulation complications, Escherichia coli Infections complications, Purpura pathology, Sepsis complications
- Published
- 2009
- Full Text
- View/download PDF
149. Short- and long-term stability study of lyophilized solid lipid nanoparticles for gene therapy.
- Author
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del Pozo-Rodríguez A, Solinís MA, Gascón AR, and Pedraz JL
- Subjects
- Cell Line, Cell Survival drug effects, Drug Stability, Drug Storage, Freeze Drying, Humans, Humidity, Particle Size, Plasmids, Temperature, Time Factors, Transfection, Trehalose chemistry, Genetic Therapy methods, Genetic Vectors chemistry, Lipids administration & dosage, Nanoparticles chemistry
- Abstract
Most studies in gene therapy are focused on developing more efficient non-viral vectors, ignoring their stability, even though physically and chemically stable vectors are necessary to achieve large easily shipped and stored batches. In the present work, the effect of lyophilization on the morphological characteristics and transfection capacity of solid lipid nanoparticles (LyoSLN) and SLN-DNA vectors (Lyo(SLN-DNA)) has been evaluated. The lyophilized preparations were stored under three different sets of temperature and humidity ICH conditions: 25 degrees C/60%RH, 30 degrees C/65%RH and 40 degrees C/75%RH. After lyophilization we found an increase in particle size which did not imply a reduction of "in vitro" transfection capacity. Stability studies of formulations lyophilized with trehalose showed that SLNs were physically stable during 9 months at 25 degrees C/60%RH and 6 months at 30 degrees C/65%RH. This stability was lost when harder conditions were employed (40 degrees C/75%RH). LyoSLNs maintained or increased the transfection efficacy (from 19% to approximately 40% EGFP positive cells) over time only at 25 degrees C/60%RH and 30 degrees C/65%RH. Lyo(SLN-DNA) resulted in almost no transfection under all conditions. LyoSLNs showed less DNA condensation capacity, whereas in Lyo(SLN-DNA) the plasmid became strongly bound, hampering the transfection. Furthermore, the storage of lyophilized lipoplexes stabilized with the disaccharide trehalose did not affect cell viability.
- Published
- 2009
- Full Text
- View/download PDF
150. A proline-rich peptide improves cell transfection of solid lipid nanoparticle-based non-viral vectors.
- Author
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del Pozo-Rodríguez A, Pujals S, Delgado D, Solinís MA, Gascón AR, Giralt E, and Pedraz JL
- Subjects
- Cell Line, Cell Survival, Chlorpromazine pharmacology, DNA chemistry, DNA genetics, DNA metabolism, Endocytosis drug effects, Filipin pharmacology, Gene Expression, Green Fluorescent Proteins genetics, Green Fluorescent Proteins metabolism, Humans, Peptides metabolism, Plasmids chemistry, Plasmids genetics, Proline chemistry, Protein Binding, Lipids chemistry, Nanoparticles chemistry, Peptides chemistry, Transfection methods
- Abstract
The aim of this work was to improve the transfection efficacy of solid lipid nanoparticle (SLN)-based non-viral vectors into ARPE-19 cells through the addition of Sweet Arrow Peptide (SAP). First, we prepared SAP-DNA complexes at ratios of at least 50:1, and then incorporated them into the SLNs. All formulations were able to protect DNA, and the peptide favoured the most bioactive form (supercoiled) of open circular DNA turns. In vitro transfection studies of the vectors containing the pCMS-EGFP plasmid in HEK293 and ARPE-19 cell lines revealed that incorporation of SAP led to greater transfection in both cell lines, although via different mechanisms. The presence of SAP in the formulations did not affect the viability of HEK293 or ARPE-19 cells. In HEK293 cells, SAP enabled greater uptake of the vectors, and an SAP to DNA ratio of 50:1 was sufficient for enhancing transfection. In contrast, in ARPE-19 cells, SAP induced a change in the dominant entrance mechanism, from clathrin endocytosis to caveolae/raft-dependent endocytosis, thereby decreasing use of the lysosomal pathway and consequently, reducing vector degradation. The extent to which SAP uses one mechanism or the other largely depends on its concentration in the formulation.
- Published
- 2009
- Full Text
- View/download PDF
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