Palomares Teodoro

• University of the Basque Country

Human skin exposure to ultraviolet B (UVB) radiation can result in acute photodamage through oxidative modifications of cellular components and biomolecules involved in the metabolism of dermal cells. Recently, the therapeutic potential of human adipose-derived stem cells (hASCs) has been investigated as a novel strategy for photoprotection due to...

Oxidative stress associated with neuroinflammation is a key process involved in the pathophysiology of neurodegenerative diseases, and therefore, has been proposed as a crucial target for new therapies. Recently, the therapeutic potential of human adipose-derived stem cells (hASCs) has been investigated as a novel strategy for neuroprotection. Thes...

Background: Mesenchymal stem cells, including those derived from human adipose tissue (hASCs), are currently being widely investigated for cell therapy. However, when transplanted at the site of injury, the survival and engraftment rates of hASCs are low, mainly due to the harsh microenvironment they encounter, characterized by inflammation and ox...

Nanometric gel particles (CsSH/PEGBCOOH) were successfully synthesized through water in oil (W/O) emulsion by the covalent cross–linking between the primary amines of thiolated chitosan (CsSH) and the dicarboxylic poly(ethylene glycol) (PEG) derivative as cross–linker (PEGBCOOH). Thus, the amidation reaction led to the formation of stable nanosized...

Thermo- and magneto-responsive shape-memory bionanocomposites based on a fully bio-based polyurethane (PU) matrix, cellulose nanocrystals (CNCs), and magnetite nanoparticles (MNPs) were prepared. The integration of the two nanoparticle types resulted in tough materials that display a higher stiffness and storage modulus in the glassy and rubbery st...

Starch-based nanocomposite hydrogels were successfully prepared by the Diels-Alder click cross-linking reaction between furan-functionalized starch derivative and a water-soluble tetrafunctional maleimide compound, adding cellulose nanocrystals (CNC) as nanoreinforcement. The effect of increasing the CNC content on rheological and swelling properti...

Water-activated shape memory bacterial cellulose/polyurethane nanocomposites were prepared by the immersion of bacterial cellulose (BC) wet membranes into waterborne polyurethane (WBPU) dispersions for different times. The high affinity between the hydrophilic BC and water stable polyurethane led to the coating and embedding of the BC membrane into...

Human adipose‐derived stem cells (ASCs), despite being one of the most attractive cell populations for tissue engineering and regenerative medicine, currently have certain limitations that reduce their therapeutic efficacy. One of the most serious problems is the poor engraftment of cryopreserved ASCs at injured tissue, attributed to the diminished...

In this work, different thermoresponsive biobased polyurethane (PU) bionanocomposites with chitin nanocrystals (CHNCs) are prepared. The behavior of the biobased PU used as matrix differs from common polyurethanes, since hard segment is constituted by the macrodiol and soft segment by a biobased diisocyanate and chain extender. The effect of CHNC c...

The precise role and value of incorporating nanoforms in biologically active matrices for medical applications is not known. In our current work, we incorporate two chitin nanoforms (i.e., nanocrystals or nanofibers) into Genipin-chitosan crosslinked matrices. These materials were studied as 2D films and 3D porous scaffolds to assess their potentia...

Oxidative stress is a common feature in neurodegenerative diseases associated with neuroinflammation, and therefore, has been proposed as a key target for novel therapies for these diseases. Recently, adipose-derived stem cell (ASC)-based cell therapy has emerged as a novel strategy for neuroprotection. In this study, we evaluate the therapeutic ro...

In the present study, the relationship between molecular structure and mechanical properties for a medium chain length polyhydroxyalkanoate (mcl-PHA) composed of 3-hydroxyoctanoate and 3-hydroxyhexanoate was elucidated. The mcl-PHA was crystallized from the melt at four different temperatures between its glass transition and melting point (37, 21,...

Background: To date, lactate dehydrogenase (LDH) and S100B remain the most useful biomarkers for follow-up of melanoma patients. In recent years, indoleamine 2,3-dioxygenase (IDO), an immunosuppressive enzyme, has been proposed as a new potential tumour biomarker for melanoma. However, further studies are needed to confirm the usefulness of IDO ex...

Biobased crosslinked polyurethanes were synthesized and characterized as shape-memory polymers. Both the macrodiol and the diisocyanate were derived from renewable sources; the first one from castor oil, and the second one from l-lysine amino acid. The influence of component molar ratios, crosslink density and maximum elongation on the shape-memory...

Here it is addressed the results on the preparation of a novel set of biocompatible thermoplastic polyurethane (PU) elastomers. The main purpose of this work was to study the nano/microstructure obtained when substituting commonly used aromatic diisocyanates, such as 4,4′-methylene diphenyl diisocyanate (MDI) by the more biocompatible and also more...

Ultraviolet radiations have many detrimental effects in living organisms that challenge the stability and function of cellular structures. UV exposure also alters the properties and durability of materials and affects their lifetime. It is becoming increasingly important to develop new biocompatible and environmentally friendly materials to address...

We describe a novel wound dressing (HR006) with two components: a lyophilized matrix of the galactomannan from locust bean gum (LBG) and an antioxidant hydration solution (AHsol) containing curcumin and N-acetyl-L-cysteine (NAC). Physico-structural analyses of the LBG matrix revealed homogeneous interconnected pores with high absorbing capacity sho...

Incorporation of bioactive glass (BG) particles to synthetic polymer scaffolds is a promising strategy to improve the bioactivity of bioinert materials and to stimulate specific cell responses. In this study the influence of incorporating BG particles to lactide and caprolactone based porous scaffolds on osteogenic differentiation of adipose-derive...

Bionanocomposite materials, combining the properties of bio-polymers and nanostructured materials are attracting interest of the wider scientific community due to their potential application in design of novel implants, drug delivery systems and tissue design platforms. Herein, we report on the use of maleimide-coated silver nanoparticles (Ag NPs)...

Most new advances in tissue engineering (TE) focus on the creation of adequate microenvironments that may accelerate the repair processes of damaged tissues. Extracellular matrix (ECM) of Wharton's jelly (WJ) from umbilical cords is very rich in sulphated GAGs (sGAGs) and hyaluronic acid (HA), components which have special properties that could pos...

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Introduction: The repair process in tissue engineering needs an adequate environment, which can be provided by biomaterials that may function as temporary extracellular matrix (ECM). In this sense, Wharton Jelly (WJ) present in umbilical cord (UC) contains two essential components of the ECM: sulfated GAGs (sGAGs) and hyaluronic acid (HA). In a pre...

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The present invention relates to a biomaterial, specifically a hydrogel, formed from the extracellular matrix of the umbilical cord for its application in regenerative medicine. The invention particularly relates to a biomaterial made up of glycosaminoglycans isolated exclusively from the Wharton's jelly of the umbilical cord which can optionally c...

Colorectal cancer (CRC) is the second most common cause of cancer death worldwide [1]. The liver is the most frequent site of metastasis in CRC, both at the time of diagnosis (15-20% of cases) and after apparently radical surgery on the primary tumour (nearly 40% of cases). If patients with colorectal liver metastasis (CRC-LM) are not treated, prog...

Biomaterials and, especially, scaffolds may function as temporary extracellular matrix (ECM), mimicking in vivo environmental structures and facilitating cell growth and tissue regeneration. ECM is composed mostly of glycosaminoglycans (GAGs) and proteins, the ratio of GAGs, hyaluronic acid (HA):sulphated GAGs (sGAGs) being characteristic of each t...

We previously demonstrated a stimulating effect of hepatectomy on residual tumor cells after resection of liver metastases. The aim of this study was to analyze the effect of all-trans-retinoic acid (ATRA) on the protumor effect of hepatectomy and survival of hepatectomized rats bearing liver metastases. We also explored whether ATRA interfered wit...

Shape-memory bionanocomposites based on a naturally sourced segmented thermoplastic polyurethane and chitin nanocrystals were synthesized and their mechanical properties and thermally-activated shape-memory behavior were studied. The chitin nanocrystals were incorporated during the synthesis of the prepolymer made from a castor oil-based difunction...

In the field of tissue engineering, the repair of tissue defects needs an appropriate scaffold that provides a favorable microenvironment for the regeneration process. Sulfated GAGs (sGAGs) and hyaluronic acid (HA) are important extracellular matrix (ECM) components. In this sense, the extracellular matrix of Wharton jelly (WJ) present in umbilical...

There has been a great deal of interest in the use of nanostructured bacterial cellulose membranes for biomedical applications, including tissue implants, wound healing and drug delivery. However, as bacterial cellulose does not intrinsically present antimicrobial properties, in the present study, antimicrobial bacterial cellulose membranes were ob...

A series of bacterial cellulose-poly(2-hydroxyethyl methacrylate) nanocomposite films was prepared by in situ radical polymerization of 2-hydroxyethyl methacrylate (HEMA), using variable amounts of poly(ethylene glycol) diacrylate (PEGDA) as cross-linker. Thin films were obtained, and their physical, chemical, thermal, and mechanical properties wer...

Bioresorbable polylactides are one of the most important materials for tissue engineering applications. In this work we have prepared scaffolds based on the two optically pure stereoisomers: poly(L: -lactide) (PLLA) and poly(D: -lactide) (PDLA). The crystalline structure and morphology were evaluated by DSC, AFM and X-ray diffraction. PLLA and PDLA...

Precursors of polyurethane chains have been reacted by means of in situ polymerization with organically modified montmorillonite clay to obtain polyurethane nanocomposites containing from 1 to 4 wt % of nanoreinforcement. The effective final dispersion of inorganic component at nanometric scale was investigated by X-ray diffraction, atomic force mi...

Glutathione has been implicated in growth factor-mediated chemoresistance of colon cancer cells. We evaluated the influence of hepatocyte growth factor, vascular endothelial growth factor and epidermal growth factor on the effect of 5-fluorouracil, oxaliplatin and SN-38 (the active metabolite of irinotecan) on WiDr cells. We also analysed the effec...

Una de las señas de identidad de una universidad es su modelo de educativo. Dicho modelo resulta fundamental para entender su estilo de enseñanza – aprendizaje, conocer los elementos que impulsan su desarrollo curricular, garantizar la calidad continua de sus enseñanzas y establecer un proyecto social a futuro. Ahora mas que nunca las universidades...

A common cause of treatment failure in colorectal cancer is chemoresistance, which may be related to the redox state of cancer cells and the tumour microenvironment, where growth factors (GFs) play an important role. Glutathione (GSH), a key regulator of the redox balance, is involved in GF signalling systems and may also protect against drug-induc...

Biodegradable and biocompatible polyether-polyester urethanes with different hard segment contents and their nanocomposites were synthesized using different amounts of modified montmorillonite, Cloisite ® 30B (C30B). Analysis of thermal and mechanical properties as well as morphological characterization was carried out by means of different experim...

Background/aims: To analyze the effect of liver resection on the progression of liver metastases in a rhabdomyosarcoma rat model. Methods: Liver metastases were induced by intrasplenic injection of S4MH rhabdomyosarcoma cells in WAG/RijCrl rats. In a first experiment, rats were sequentially sacrificed until day 30 following tumor cell inoculatio...

This work analyzes the opinion of students, attending different degrees, on the didactic utility of information and communication technologies (ICTs) at the university. Web Pages and e-mail were used to facilitate different educational tools (educational scripts, articles, web pages, practical classwork and references). The univariate and multivari...

This work analyzes the opinion of students. attending, different degrees, on the didactic utility of information and communication technologies (ICTs) at the university. Web pages and e-mail were used to facilitate different educational tools (educational scripts, articles, web pages. practical classworks and references). The univariate and multiva...

Differentiation therapy with retinoic acid has been considered a potential approach for treating rhabdomyosarcoma. Analysis of retinoids as differentiating agents for rhabdomyosarcoma is, however, rendered incomplete by the fact that some rhabdomyosarcoma cell lines are retinoic acid resistant. Therefore, the aim of the present work was to study th...

Glutathione (GSH), the most prevalent intracellular non-protein thiol, plays an important role in the interleukin-2 (IL-2)-induced proliferative activity of normal and tumour cells expressing IL-2 receptor (IL-2R). In the present study, we investigate the effect of IL-2 on proliferation of the human melanoma A375 cell line, and the possible selecti...

El objetivo fundamental del presente estudio es analizar el impacto de la aplicaci�n de las Tecnolog�as de la Informaci�n y Comunicaci�n (TIC's) como elemento did�ctico de autoaprendizaje y facilitador motivacional en la docencia universitaria presencial. El trabajo emp�rico realizado consiste en la aplicaci�n de distintas herramientas acad�micas e...

All-trans-retinoic acid (ATRA) promotes cell differentiation. We have studied its effect on the local recurrence and metastatic spreading of an experimental rhabdomyosarcoma in rats. syngenic rhabdomyosarcoma cells (S4MH) were inoculated s.c. in male WAG/RijCrl rats. After 25 days tumors were excised and a 40% hepatectomy was performed for all anim...

In the early stages of metastasis, development of the disease is dependent on growth factors produced by the host. There are clinical situations associated with an increase in these factors, such as partial resection of metastasized liver. Given the important role of hepatotrophic factors in liver regeneration, we have studied the effect of partial...

Glutathione (GSH) is involved in many cellular functions, including cell growth and differentiation. GSH also plays an important role in the protection of cells against oxidative damage and hence in determining the sensitivity of cells to the cytotoxicity of anticancer agents. Because of this, induction of GSH depletion has been proposed as a good...

The efficacy of sequential chemoimmunotherapy involving interleukin-2 (IL2) in metastatic melanoma is limited, in part, by the severe toxicity associated with most therapeutic regimens. Glutathione (GSH), the most prevalent intracellular non-protein thiol, plays an important role in protecting against cellular injury caused by various anticancer ag...

Expression of determined Asn-bound glycans (N-glycans) in cell surface glycoproteins regulates different processes in tumour cell biology. Specific patterns of N-glycosylation are displayed by highly metastatic cells and it has been shown that inhibition of N-glycan processing restrains cell proliferation and induces cell death via apoptosis. Howev...

Highly metastatic cells are known to overexpress certain Asn-linked oligosaccharides in the plasmatic membrane. Another phenotypic characteristic of malignant cells consists in the expression of high levels of intracellular glutathione (GSH). The aim of the present work was to demonstrate that the inhibition of N-glycosylation induces changes in in...

Glutathione (GSH) is the major non-protein thiol in cells that plays a critical role against damage from electrophilic agents such as alkylating drugs. Selective therapeutic GSH elevation in normal but not in tumour cells has been suggested as a means of protecting host tissues against more intense doses of chemotherapy. The present study investiga...

In this study we compare the effects of treatment with external sodium adenosine 5'-triphosphate (ATP) with the effects of L-buthionine-SR-sulfoximine (BSO) on B16 melanoma growth and on the modulation of the cytotoxic antimelanoma activity of cyclophosphamide (CY). We evaluated the in vitro effects of treatment with ATP or BSO on intracellular glu...

Glutathione (GSH) plays an essential role in the metabolism of melanoma. As changes in intracellular GSH content can modify the processes of cell proliferation and detoxification, this could determine the therapeutic response to some cancer treatment strategies. The purpose of this study was to test the effects of treatment with interleukin-2 (IL-2...

In the clinical evolution of malign tumors, prognosis depends on whether metastasis develops or not. Biologically speaking, the formation of metastasis implies the existence of tumor cells capable of successfully performing all the steps in the metastatic process: local invasion, lymphatic or hematogenous dissemination, arrest in the microvascular...

Depletion of glutathione (GSH) has been proposed as a useful antitumour approach, increasing cellular sensitivity to other anticancer. GSH is a ubiquitous tripeptyde thiol that has a critical role in protection of cells against the cytotoxic effects of a wide variety of drugs, such as activated cyclophosphamide (CY). It has been demonstrated that G...

The role of interleukin-2 (IL-2) on tumor growth of B16F10 melanoma cells was assessed in two sets of mice with different immune status: normal (immunocompetent) mice and immunodeficient mice. The two sets of animals were treated with cyclophosphamide (CY) or IL-2 alone or with a combined therapy of CY+IL-2. On days 6 and 10 after tumor cell inject...

We designed a protocol for cell labeling with the lectin wheat germ agglutinin (WGA) linked to the fluorochrome tetramethyl-rhodamine isothiocyanate (TRITC) for effective detection of the B16F10 melanoma and Lewis lung carcinoma (LLc) cells on pulmonary histological sections from C57BL/6 mice. We have also determined a suitable concentration of WGA...

We compare the survival of four sets of mice bearing hepatic metastases from B16F10 melanoma: control non-treated mice; mice treated with cyclosphosphamide; mice treated with interleukin-2 (IL-2) and mice undergoing a therapy by combination of cyclophosphamide plus IL-2. The three sets of treated mice showed a higher survival (p < 0.05) with respec...

El objetivo fundamental del presente estudio es analizar el impacto de la aplicación de las Tecnologías de la Información y Comunicación (TIC¿s) como elemento didáctico de autoaprendizaje y facilitador motivacional en la docencia universitaria presencial. El trabajo empírico realizado consiste en la aplicación de distintas herramientas académicas e...