EMT and EGFR in CTCs cytokeratin negative non-metastatic breast cancer.

Circulating tumor cells (CTCs) are frequently associated with epithelial-mesenchymal transition (EMT).The objective of this study was to detect EMT phenotype through Vimentin (VIM) and Slug expression in cytokeratin (CK)-negative CTCs in non-metastatic breast cancer patients and to determine the importance of EGFR in the EMT phenomenon. In CK-negative CTCs samples, both VIM and Slug markers were co-expressed in the most of patients. Among patients EGFR+, half of them were positive for these EMT markers. Furthermore, after a systemic treatment 68% of patients switched from CK- to CK+ CTCs. In our experimental model we found that activation of EGFR signaling by its ligand on MCF-7 cells is sufficient to increase EMT phenotypes, to inhibit apoptotic events and to induce the loss of CK expression. The simultaneous detection of both EGFR and EMT markers in CTCs may improve prognostic or predictive information in patients with operable breast cancer.

Osteoarticular Expression of Musashi-1 in an Experimental Model of Arthritis.

Background. Collagen-induced arthritis (CIA), a murine experimental disease model induced by immunization with type II collagen (CII), is used to evaluate novel therapeutic strategies for rheumatoid arthritis. Adult stem cell marker Musashi-1 (Msi1) plays an important role in regulating the maintenance and differentiation of stem/precursor cells. The objectives of this investigation were to perform a morphological study of the experimental CIA model, evaluate the effect of TNFα-blocker (etanercept) treatment, and determine the immunohistochemical expression of Msi1 protein. Methods. CIA was induced in 50 male DBA1/J mice for analyses of tissue and serum cytokine; clinical and morphological lesions in limbs; and immunohistochemical expression of Msi1. Results. Clinically, TNFα-blocker treatment attenuated CIA on day 32 after immunization (P < 0.001). Msi1 protein expression was significantly higher in joints damaged by CIA than in those with no lesions (P < 0.0001) and was related to the severity of the lesions (Spearman's rho = 0.775, P = 0.0001). Conclusions. Treatment with etanercept attenuates osteoarticular lesions in the murine CIA model. Osteoarticular expression of Msi1 protein is increased in joints with CIA-induced lesion and absent in nonlesioned joints, suggesting that this protein is expressed when the lesion is produced in order to favor tissue repair.

Edge vascular response after polymer-free vs. polymer-based paclitaxel-eluting stent implantation.

BACKGROUND It is unknown if lack of polymer can provoke a different edge response in drug-eluting stents. The aim of this study was to compare edge vascular response between polymer-free paclitaxel-eluting stent (PF-PES) and polymer-based paclitaxel-eluting stents (PB-PES). METHODS AND RESULTS: A total of 165 eligible patients undergoing percutaneous coronary intervention were prospectively randomized 1:1 to receive either PF-PES or PB-PES. Those patients with paired intravascular ultrasound (IVUS) after procedure and at 9-month follow-up were included in this analysis.Seventy-six patients with 84 lesions, divided into PB-PES (38 patients, 41 lesions) and PF-PES groups (38 patients, 43 lesions) had paired post-procedure and 9-month follow-up IVUS and were therefore included in this substudy. There was a significant lumen decrease at the proximal edge of PF-PES (from 9.02±3.06 mm(2)to 8.47±3.05 mm(2); P=0.040), and a significant plaque increase at the distal edges of PF-PES (from 4.39±2.73 mm(2)to 4.78±2.63 mm(2); P=0.004). At the distal edge there was a significant plaque increase in the PF-PES compared to PB-PES (+8.0% vs. -0.6%, respectively; P=0.015) with subsequent lumen reduction (-5.2% vs. +6.0%, respectively; P=0.024). CONCLUSIONS PF-PES had significant plaque increase and lumen reduction at the distal edge as compared to PB-PES, probably due to difference in polymer-based drug-release kinetics between the 2 platforms.

Preparació d'un ciment ossi acrílic modificat amb hidroxiapatita d'origen natural

El ciment ossi es prepara barrejant dos components, un sòlid (en format de pols) i l'altre líquid. En general, en la major part de productes comercials el constituent en pols conté polimetacrilat de metil (PMMA), un agent radioopac i peròxid de benzoïl (BPO) com a iniciador, mentre que el component líquid conté metacrilat de metil (MMA) com a monòmer i com activador la (N,Ndimetil- p-toluidina). Els continguts de cada constituent poden variar lleugerament d'una marca comercial a una altra. En barrejar els dos components es produeix la polimerització i té lloc l'enduriment del ciment. Es planteja la modificació de la formulació convencional del ciment ossi acrílic amb el component inorgànic majoritari dels ossos, és a dir, la hidroxiapatita (HA) (fosfat doble de sodi i calci) amb una relació molar (Ca/P) de 1,67. La HA i particularment la d’origen mineral o de síntesi, no és un component innovador en aquesta disciplina científica, però l’ús de la HA d’origen natural (procedent d’ossos de porc) introdueix la possibilitat d’incorporar un material molt econòmic que pot millorar la resistència mecànica del material sense perjudici de millorar la biocompatibilitat amb teixit ossi viu. Es planteja un treball de cerca d’un material que permeti la fixació de pròtesis articulades o bé pugui ser considerat com a sistema de farciment de cavitat òssies derivades de procesos osteoporòtics. Per arribar a trobar aquest material amb les propietats desitjades es preparen ciments amb diferents continguts en HA natural. Posteriorment es caracteritzen diferents propietats fisico-químiques dels materials les quals permetran prendre decisions a l’hora de determinar la viabilitat tècnica dels materials (tèrmic, mecànic i morfològic). Finalment, es realitza un estudi “in vitro” amb cultius cel•lulars per tal de determinar la biocompatibilitat del material

Transformació d'una màquina de tecnologia additiva per a la fabricació d'scaffolds

Grup de Recerca en Enginyeria de Producte, Procés i Producció de la Universitat de Girona té en les seves instal•lacions una RepRap model Prusa Mendel. Un dels seus àmbits d’investigació és el sector mèdic. Una de les aplicacions més innovadores de les tecnologies additives, emmarcada dins del camp mèdic, és la fabricació de scaffolds. En la medicina regenerativa, els scaffolds s’utilitzen com estructures biodegradables implantables que serveixen de base per a la correcte reproducció de teixit a partir de cèl•lules no diferenciades. L’objecte del projecte és aconseguir fabricar scaffolds amb la Reprap. Per tald’assolir aquest objectiu final caldran molts passos previs. En el moment que s’inicia elpresent projecte la RepRap té tots els seus components muntats, el cablejat instal•lat i el firmware inicial a la placa. Així, en primer lloc cal obtenir una correcta comunicació entre la màquina i l’ordinador a través del qual es podrà accedir a la placa per tal de realizar ajustaments. Una vegada la màquina obeeixi les ordres de moviment en la magnitud i la direcció desitjada serà el moment d’ajustar els paràmetres propis de la impressió. Aquests varien en funció de l’extrusor i el material a utilitzar. En aquest punt es passarà a dissenyar i fabricar diferents tipus de scaffolds variant les estratègies i les geometries. Aquests dissenys seran testats mecànicament a compressió. També seran analitzats geomètricament i se’n determinarà la porositat. Finalment, a partir de l’anàlisi dels resultats s’intentarà trobar una relació entre les diferents formes geomètriques, les porositats i la resistència

Pathways for the synthesis of polyesters in plants; cutin, suberin, and polyhydroxyalkanoates

Plants naturally produce the lipid-derived polyester cutin, which is found in the plant cuticle that is deposited at the outermost extracellular matrix of the epidermis covering nearly all aboveground tissues. Being at the interface between the cell and the external environment, cutin and the cuticle play important roles in the protection of plants from several stresses. A number of enzymes involved in the synthesis of cutin monomers have recently been identified, including several P450s and one acyl-CoA synthetase, thus representing the first steps toward the understanding of polyester formation and, potentially, polyester engineering to improve the tolerance of plants to stresses, such as drought, and for industrial applications. However, numerous processes underlying cutin synthesis, such as a controlled polymerization, still remain elusive. Suberin is a second polyester found in the extracellular matrix, most often synthesized in root tissues and during secondary growth. Similar to cutin, the function of suberin is to seal off the respective tissue to inhibit water loss and contribute to resistance to pathogen attack. Being the main constituent of cork, suberin is a plant polyester that has already been industrially exploited. Genetic engineering may be worth exploring in order to change the polyester properties for either different applications or to increase cork production in other species. Polyhydroxyalkanoates (PHAs) are attractive polyesters of 3-hydroxyacids because of their properties as bioplastics and elastomers. Although PHAs are naturally found in a wide variety of bacteria, biotechnology has aimed at producing these polymers in plants as a source of cheap and renewable biodegradable plastics. Synthesis of PHA containing various monomers has been demonstrated in the cytosol, plastids, and peroxisomes of plants. Several biochemical pathways have been modified in order to achieve this, including the isoprenoid pathway, the fatty acid biosynthetic pathway, and the fatty acid β-oxidation pathway. PHA synthesis has been demonstrated in a number of plants, including monocots and dicots, and up to 40% PHA per gram dry weight has been demonstrated in Arabidopsis thaliana. Despite some successes, production of PHA in crop plants remains a challenging project. PHA synthesis at high level in vegetative tissues, such as leaves, is associated with chlorosis and reduced growth. The challenge for the future is to succeed in synthesis of PHA copolymers with a narrow range of monomer compositions, at levels that do not compromise plant productivity. This goal will undoubtedly require a deeper understanding of plant biochemical pathways and how carbon fluxes through these pathways can be manipulated, areas where plant "omics" can bring very valuable contributions.

Immune cell impact of three differently coated lipid nanocapsules: pluronic, chitosan and polyethylene glycol.

Lipid nanocapsules (NCs) represent promising tools in clinical practice for diagnosis and therapy applications. However, the NC appropriate functionalization is essential to guarantee high biocompatibility and molecule loading ability. In any medical application, the immune system-impact of differently functionalized NCs still remains to be fully understood. A comprehensive study on the action exerted on human peripheral blood mononuclear cells (PBMCs) and major immune subpopulations by three different NC coatings: pluronic, chitosan and polyethylene glycol-polylactic acid (PEG) is reported. After a deep particle characterization, the uptake was assessed by flow-cytometry and confocal microscopy, focusing then on apoptosis, necrosis and proliferation impact in T cells and monocytes. Cell functionality by cell diameter variations, different activation marker analysis and cytokine assays were performed. We demonstrated that the NCs impact on the immune cell response is strongly correlated to their coating. Pluronic-NCs were able to induce immunomodulation of innate immunity inducing monocyte activations. Immunomodulation was observed in monocytes and T lymphocytes treated with Chitosan-NCs. Conversely, PEG-NCs were completely inert. These findings are of particular value towards a pre-selection of specific NC coatings depending on biomedical purposes for pre-clinical investigations; i.e. the immune-specific action of particular NC coating can be excellent for immunotherapy applications.

Tightness of random knotting.

Long polymers in solution frequently adopt knotted configurations. To understand the physical properties of knotted polymers, it is important to find out whether the knots formed at thermodynamic equilibrium are spread over the whole polymer chain or rather are localized as tight knots. We present here a method to analyze the knottedness of short linear portions of simulated random chains. Using this method, we observe that knot-determining domains are usually very tight, so that, for example, the preferred size of the trefoil-determining portions of knotted polymer chains corresponds to just seven freely jointed segments.

Predicting optimal lengths of random knots

In a thermally fluctuating long linear polymeric chain in a solution, the ends, from time to time, approach each other. At such an instance, the chain can be regarded as closed and thus will form a knot or rather a virtual knot. Several earlier studies of random knotting demonstrated that simpler knots show a higher occurrence for shorter random walks than do more complex knots. However, up to now there have been no rules that could be used to predict the optimal length of a random walk, i.e. the length for which a given knot reaches its highest occurrence. Using numerical simulations, we show here that a power law accurately describes the relation between the optimal lengths of random walks leading to the formation of different knots and the previously characterized lengths of ideal knots of a corresponding type.

Biopolymers

Plants naturally synthesize a variety of polymers that have been used by mankind as a source of useful biomaterials. For example, cellulose, the main constituent of plant cell wall and the most abundant polymer on earth, has been used for several thousand years as a source of fibers for various fabrics. Similarly, rubber extracted from the bark of the tree Hevea brasiliensis, has been a major source of elastomers until the development of similar synthetic polymers. In the last century, the usefulness of plant polymers as biomaterials has been expanded through the chemical modification of the natural polymers. For example, a number of plastics have been made by substituting the hydroxyl groups present on the glucose moiety of cellulose with larger groups, such as nitrate or acetate, giving rise to materials such as cellulose acetate, a clear plastic used in consumer products such as toothbrush handles and combs. Similarly, starch has been used in the manufacture of plastics by either using it in blends with synthetic polymers or as the main constituent in biodegradable plastics. The advent of transformation and expres- sion of foreign genes in plants has created the possibility of expanding the usefulness of plants to include the synthesis of a range of biomolecules. In view of the capacity of certain crops to produce a large quantity of organic raw material at low cost, such as oils and starch, it is of interest to explore the possibility of using transgenic plants as efficient vectors for the synthesis of biopolymers. Such plant based biopolymers could replace, in part, the synthetic plastics and elastomers produced from petroleum, offering the advantage of renewability and sustainability. Furthermore, being natural pro- ducts, biopolymers are usually biodegradable and can thus contribute to alleviate problems associated with the management of plastic waste. In this article, the emphasis will be on the use of transgenic plants for the synthesis of two novel classes of industrially useful polymers, namely protein based polymers made from natural or artificial genes, and polyhydroxyalkanoates, a family of bacterial poly- esters having the properties of biodegradable plastics and elastomers.

Anharmonicity contributions to the vibrational second hyperpolarizability of conjugated oligomers

Restricted Hartree-Fock 6-31G calculations of electrical and mechanical anharmonicity contributions to the longitudinal vibrational second hyperpolarizability have been carried out for eight homologous series of conjugated oligomers - polyacetylene, polyyne, polydiacetylene, polybutatriene, polycumulene, polysilane, polymethineimine, and polypyrrole. To draw conclusions about the limiting infinite polymer behavior, chains containing up to 12 heavy atoms along the conjugated backbone were considered. In general, the vibrational hyperpolarizabilities are substantial in comparison with their static electronic counterparts for the dc-Kerr and degenerate four-wave mixing processes (as well as for static fields) but not for electric field-induced second harmonic generation or third harmonic generation. Anharmonicity terms due to nuclear relaxation are important for the dc-Kerr effect (and for the static hyperpolarizability) in the σ-conjugated polymer, polysilane, as well as the nonplanar π systems polymethineimine and polypyrrole. Restricting polypyrrole to be planar, as it is in the crystal phase, causes these anharmonic terms to become negligible. When the same restriction is applied to polymethineimine the effect is reduced but remains quantitatively significant due to the first-order contribution. We conclude that anharmonicity associated with nuclear relaxation can be ignored, for semiquantitative purposes, in planar π-conjugated polymers. The role of zero-point vibrational averaging remains to be evaluated

Effective Structural Concrete Repair, Volume 1 of 3, Repair of Impact Damaged Prestressed Concrete Beams with CFRP, March 2004

Structural concrete is one of the most commonly used construction materials in the United States. However, due to changes in design specifications, aging, vehicle impact, etc. – there is a need for new procedures for repairing concrete (reinforced or pretressed) superstructures and substructures. Thus, the overall objective of this investigation was to develop innovative cost effective repair methods for various concrete elements. In consultation with the project advisory committee, it was decided to evaluate the following three repair methods: • Carbon fiber reinforced polymers (CFRPs) for use in repairing damaged prestressed concrete bridges • Fiber reinforced polymers (FRPs) for preventing chloride penetration of bridge columns • Various patch materials The initial results of these evaluations are presented in this three volume final report. Each evaluation is briefly described in the following paragraphs. A more detailed abstract of each evaluation accompanies the volume on that particular investigation.

Effective Structural Concrete Repair, Volume 2 of 3, Use of FRP to Prevent Chloride Penetration in Bridge Columns, March 2004

Structural concrete is one of the most commonly used construction materials in the United States. However, due to changes in design specifications, aging, vehicle impact, etc. – there is a need for new procedures for repairing concrete (reinforced or pretressed) superstructures and substructures. Thus, the overall objective of this investigation was to develop innovative cost effective repair methods for various concrete elements. In consultation with the project advisory committee, it was decided to evaluate the following three repair methods: • Carbon fiber reinforced polymers (CFRPs) for use in repairing damaged prestressed concrete bridges • Fiber reinforced polymers (FRPs) for preventing chloride penetration of bridge columns • Various patch materials The initial results of these evaluations are presented in this three volume final report. Each evaluation is briefly described in the following paragraphs. A more detailed abstract of each evaluation accompanies the volume on that particular investigation.

Effective Structural Concrete Repair, Volume 3 of 3, Evaluation of Repair Materials for Use in Patching Damaged Concrete, March 2004

Structural concrete is one of the most commonly used construction materials in the United States. However, due to changes in design specifications, aging, vehicle impact, etc. – there is a need for new procedures for repairing concrete (reinforced or pretressed) superstructures and substructures. Thus, the overall objective of this investigation was to develop innovative cost effective repair methods for various concrete elements. In consultation with the project advisory committee, it was decided to evaluate the following three repair methods: • Carbon fiber reinforced polymers (CFRPs) for use in repairing damaged prestressed concrete bridges • Fiber reinforced polymers (FRPs) for preventing chloride penetration of bridge columns • Various patch materials The initial results of these evaluations are presented in this three volume final report. Each evaluation is briefly described in the following paragraphs. A more detailed abstract of each evaluation accompanies the volume on that particular investigation.