Aggrecan catabolism during mesenchymal stromal cell in vitro chondrogenesis

María Lucía Gutiérrez,Johana María Guevara,Olga Yaneth Echeverri,Diego Garzón-Alvarado,Luis Alejandro Barrera 한국통합생물학회 2013 Animal cells and systems Vol.17 No.4

During skeleton formation, mesenchymal cells condense and differentiate into chondrocytes in a process known as chondrogenesis. Glycosaminoglycans (GAGs), main components of aggrecan in the extracellular matrix (ECM),have an important role in this process. An in vitro simplified system has been devised to study chondrogenesis using mesenchymal progenitor cells. Although the capacity of mesenchymal stromal cells to differentiate into the chondrogenic lineage is well established, there is a lack of knowledge with respect to lysosomal enzyme activity during the chondrogenic process. To further understand GAG’s catabolic activities during in vitro chondrogenesis, we evaluated three lysosomal enzymes. Chondrogenic differentiation was demonstrated by Alcian blue positive stain quantified by a grading system using ImageJ. Enzyme activity for N-acetylgalactosamine-6-sulfate-sulfatase during chondrogenic induction decreased significantly with time of culture; b-galactosidase enzyme activity had a similar tendency of temporal activity. On the contrary, b-glucuronidase enzyme activity decreased from the first to second week of induction, but remained the same during the third week of culture. Aggrecan’s immunohistochemistry values for aggregates under chondrogenic induction revealed a similar temporal pattern to that of N-acetylgalactosamine-6-sulfate-sulfatase and b-galactosidase enzyme activity. This work has contributed to the evaluation of enzyme activities associated with GAG degradation, critical component of cartilage ECM. These findings are relevant in understanding the role of enzymes responsible for degradation of molecules predominantly synthesized in the chondrogenic differentiation process. A better understanding of the roles of these enzymes during development could help elucidate further association of deficiencies of these enzymes in skeletal pathologies, primarily chondrodysplasias.

Endodontic micro-resurgery and guided tissue regeneration of a periapical cyst associated to recurrent root perforation: a case report

Córdova-Malca Fernando,Coaguila-Llerena Hernán,Garré-Arnillas Lucía,Rayo-Iparraguirre Jorge,Faria Gisele 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.4

Although the success rates of microsurgery and micro-resurgery are very high, the influence of a recurrent perforation combined with radicular cyst remains unclear. A 21-year-old white female patient had a history of root perforation in a previously treated right maxillary lateral incisor. Analysis using cone-beam computed tomography (CBCT) revealed an extensive and well-defined periapical radiolucency, involving the buccal and palatal bone plate. The perforation was sealed with bioceramic material (Biodentine) in the pre-surgical phase. In the surgical phase, guided tissue regeneration (GTR) was performed by combining xenograft (lyophilized bovine bone) and autologous platelet-rich fibrin applied to the bone defect. The root-end preparation was done using an ultrasonic tip. The retrograde filling was performed using a bioceramic material (Biodentine). Histopathological analysis confirmed a radicular cyst. The patient returned to her referring practitioner to continue the restorative procedures. CBCT analysis after 1-year recall revealed another perforation in the same place as the first intervention, ultimately treated by micro-resurgery using the same protocol with GTR, and a bioceramic material (MTA Angelus). The 2-year recall showed healing and bone neoformation. In conclusion, endodontic micro-resurgery with GTR showed long-term favorable results when a radicular cyst and a recurrent perforation compromised the success.

Bio-nano interactions: Binding proteins, polysaccharides, lipids and nucleic acids onto magnetic nanoparticles

Lucía Abarca-Cabrera,Paula Fraga-García,Sonja Berensmeier 한국생체재료학회 2021 생체재료학회지 Vol.25 No.2

The major interest in nanoparticles as an application platform for biotechnology arises from their high surface-tovolume ratio. Iron oxide nanoparticles (IONPs) are particularly appealing due to their superparamagnetic behavior, which enables bioseparation using external magnetic fields. In order to design advanced biomaterials, improve binding capacities and develop innovative processing solutions, a thorough understanding of the factors governing organic-inorganic binding in solution is critical but has not yet been achieved, given the wide variety of chemical and physical influences. This paper offers a critical review of experimental studies of the interactions between low cost IONPs (bare iron oxides, silica-coated or easily-functionalized surfaces) and the main groups of biomolecules: proteins, lipids, nucleic acids and carbohydrates. Special attention is devoted to the driving forces and interdependencies responsible of interactions at the solid-liquid interface, to the unique structural characteristics of each biomolecular class, and to environmental conditions influencing adsorption. Furthermore, studies focusing on mixtures, which are still rare, but absolutely necessary to understand the biocorona, are also included. This review concludes with a discussion of future work needed to fill the gaps in knowledge of bio-nano interactions, seeking to improve nanoparticles’ targeting capabilities in complex systems, and to open the door for multipurpose recognition and bioseparation processes.

Gemini lipopeptides as vaccine adjuvants: a new role for these versatile carriers

Lucía Daniela Grippo,Ivana Gabriela Reidel,María Inés García,Alexis Streu,Diana María Müller,Carolina Melania Veaute 대한백신학회 2020 Clinical and Experimental Vaccine Research Vol.9 No.2

The design of subunit vaccines requires new adjuvant systems. We designed and synthesized new lipopeptides (cysteine-based) of low molecular weight with different hydrophobic chains that dimerize becoming gemini lipopeptides. They were characterized and their adjuvant capacity was tested in mice by the inoculation of a protein antigen formulated with the lipopeptides, with and without the addition of CpG-oligodeoxynucleotides. Formulations were able to induce an immune response and produced no adverse effects. An adjuvant ability is described for the first time for this type of molecules.

Livres, Textes et Manuscrits de Ferdinand de Saussure

Claudia Lucía Mejía Quijano,Miguel Ángel Mahecha 고려대학교 응용문화연구소 2020 에피스테메 Vol.0 No.23

Based on the criteria required for reading a book, two general notions, the “text” and the “manuscript”, are defined and explained at the beginning of this article from a semiological point of view. On this basis, several editions of Ferdinand de Saussure's manuscripts are then analysed, highlighting the deficiencies, which are often due to the disorder created in archive collections by superimposing manuscripts. A better classification of a primordial manuscript and the dating of another published manuscript are thus brought to light. Finally, it is proposed that this distinction between “text” and “manuscript” must be adopted and that Saussure's texts be favored in the reading and study of Saussure's manuscripts. A partir des variables nécessaires à la lecture d’un livre, deux notions générales, le « texte » et le « manuscrit », sont définies et expliquées au début de cet article d’un point de vue sémiologique. Sur cette base, plusieurs éditions de manuscrits de Ferdinand de Saussure sont ensuite analysées, en mettant en évidence des défauts, qui sont souvent dus au désordre créé dans les fonds d’archives par les superpositions de manuscrits. Un meilleur classement d’un manuscrit primordial et la datation d’un autre manuscrit publié sont ainsi mis en lumière. Pour finir, on propose de retenir cette distinction entre « texte » et « manuscrit », et de privilégier les textes de Saussure dans la lecture et l’étude des manuscrits saussuriens.

Protective effects of D-005, a lipid extract from Acrocomia crispa fruits, against ischemia/reperfusion-induced acute kidney injury in rats

Ambar Oyarzábal-Yera,Sandra Rodríguez-Salgueiro,Nelson Merino-García,Leyanis Ocaña-Nápoles,Lucía González-Núñez,Licet Mena-Valdés,Zullyt Zamora-Rodríguez,José A. Medina-Pírez,Sonia Jiménez-Despaigne,V 대한신장학회 2019 Kidney Research and Clinical Practice Vol.38 No.4

Background: Acute kidney injury (AKI) induced by renal ischemia/reperfusion (IR) is associated with enhanced production of reactive oxygen species in renal tissues. D-005, a lipid extract obtained from Acrocomia crispa fruit, has previously shown antioxidant effects. The aim of this work was to evaluate the effects of D-005 on renal IR-induced AKI in rats. Methods: Rats were randomized into seven groups including a negative control group (vehicle) without AKI and six groups with renal IR-induced AKI as follows: a positive control (vehicle); D-005 treatment at 25, 100, 200, or 400 mg/kg; and dexamethasone at 3 mg/kg. All treatments were orally administered as single doses 1 hour before AKI induction. Biomarkers (serum creatinine, urea, and uric acid concentrations), oxidative variables, and histopathological AKI changes were evaluated in blood and kidney tissues. Results: All D-005 doses protected against IR-induced AKI in rats by significantly decreasing biomarkers and histopathological AKI changes as assessed by reduced serum concentrations of creatinine, urea, and uric acid. In addition, all D-005 doses decreased tubular damage, as shown by fewer detached cells and casts in the tubular lumen. D-005 reversed oxidation disturbance markers by decreasing malondialdehyde and sulfhydryl group concentrations in plasma and in kidney homogenates and by increasing kidney catalase activity. Dexamethasone, the reference substance, protected against IR-induced AKI in rats by reducing biochemical and histological variables of renal damage in a similar manner. Conclusion: Administration of single oral doses of D-005 markedly and significantly protected against renal IR-induced AKI, possibly due to its known antioxidant effects.

Hydrogels for Biomedicine Based on Semi-Interpenetrating Polymeric Networks of Collagen/Guar Gum: Applications in Biomedical Field and Biocompatibility

Edith E. Lopéz-Martínez,Jesús A. Claudio-Rizo,Martín Caldera-Villalobos,Juan J. Becerra-Rodríguez,Denis A. Cabrera-Munguía,Lucía F. Cano-Salazar,Rebeca Betancourt-Galindo 한국고분자학회 2022 Macromolecular Research Vol.30 No.6

Determining the controlled release capacity of drugs with therapeutic interest as well as the biocompatibility of hydrogels based on natural and synthetic polymers is of the utmost importance to evaluate their potential performance in regenerative medicine strategies. Novel hydrogels were synthesized by semi-interpenetration of guar gum (GG) in a matrix of crosslinked collagen with hydrophilic polyurethane. GG concentrations of 10, 20, 30 and 40 wt% on the semi-IPN matrices were tested. These hydrogels have excellent in vitro biocompatibility, not demonstrating cytotoxic character for cells important in the healing process such as monocytes and fibroblasts, stimulating their proliferation, as well as evidencing hemocompatibility and antibacterial capacity. Also these matrices can encapsulate and release methylene blue in a controlled manner. The results of the evaluation of human monocyte signaling indicate that the semi-IPN matrix containing 30 wt% of GG allows higher segregation of beta-1 transforming growth factor (β1-TGF), a determinant cytokine in the construction of new tissue, showing that these hydrogels have potential application in biomedicine as dressings for chronic wound healing.

Hydrogels for Biomedicine Based on Semi-Interpenetrating Polymeric Networks of Collagen/Guar Gum: Synthesis and Physicochemical Characterization

Edith E. Lopéz-Martínez,Jesús A. Claudio-Rizo,Martín Caldera-Villalobos,Juan J. Becerra-Rodríguez,Denis A. Cabrera-Munguía,Lucía F. Cano-Salazar,Rebeca Betancourt-Galindo 한국고분자학회 2022 Macromolecular Research Vol.30 No.6

Novel synthetic strategies to produce biopolymer based hydrogels for biomedical applications are required currently. Collagen hydrogels for wound healing can improve their structural and physicochemical properties by incorporating polysaccharides within the fibrillar matrix. Novel hydrogels were synthesized by semi-interpenetration of guar gum (GG) in a matrix of crosslinked collagen with hydrophilic polyurethane. GG concentrations of 10, 20, 30, and 40 wt% on the semi- IPN matrices were tested. The addition of the polysaccharide accelerates the gelling time of the hydrogels; 30 wt% of GG allows a 68 ± 5% of physicochemical crosslinking, exhibiting a maximum swelling of 3496 ± 89% and both improved mechanical and thermal resistance. The short-range interactions established in these matrices, mainly of the hydrogen bond type, make it possible to delay their hydrolytic and proteolytic degradation. The structure and properties of these hydrogels could have potential application in biomedicine as dressings for chronic wound healing, tailoring the controlled release of drugs with therapeutic interest, cell viability and proliferation, cell signaling, hemocompatibility and antibacterial character.

THE <i>SPITZER</i> INFRARED SPECTROGRAPH SURVEY OF PROTOPLANETARY DISKS IN ORION A. I. DISK PROPERTIES

Kim, K. H.,Watson, Dan M.,Manoj, P.,Forrest, W. J.,Furlan, Elise,Najita, Joan,Sargent, Benjamin,Herná,ndez, Jesú,s,Calvet, Nuria,Adame, Lucí,a,Espaillat, Catherine,Megeath, S. T.,Muz American Astronomical Society 2016 The Astrophysical journal Supplement series Vol.226 No.1

<P>We present our investigation of 319 Class II objects in Orion A observed by Spitzer/IRS. We also present the follow-up observations of 120 of these Class II objects in Orion A from the Infrared Telescope Facility/SpeX. We measure continuum spectral indices, equivalent widths, and integrated fluxes that pertain to disk structure and dust composition from IRS spectra of Class II objects in Orion A. We estimate mass accretion rates using hydrogen recombination lines in the SpeX spectra of our targets. Utilizing these properties, we compare the distributions of the disk and dust properties of Orion A disks with those of Taurus disks with respect to position within Orion A (Orion Nebular Cluster [ONC] and L1641) and with the subgroups by the inferred radial structures, such as transitional disks (TDs) versus radially continuous full disks (FDs). Our main findings are as follows. (1) Inner disks evolve faster than the outer disks. (2) The mass accretion rates of TDs and those of radially continuous FDs are statistically significantly displaced from each other. The median mass accretion rate of radially continuous disks in the ONC and L1641 is not very different from that in Taurus. (3) Less grain processing has occurred in the disks in the ONC compared to those in Taurus, based on analysis of the shape index of the 10 mu m silicate feature (F-11.3/F-9.8). (4) The 20-31 mu m continuum spectral index tracks the projected distance from the most luminous Trapezium star, theta(1) Ori C. A possible explanation is UV ablation of the outer parts of disks.</P>

Influence of the actions observed on cervical motion in patients with chronic neck pain : a pilot study

Lucía de-la-Puente-Ranea,Beatriz García-Calvo,Roy La Touche,Josué Fernández-Carnero,Alfonso Gil-Martínez 한국운동재활학회 2016 JER Vol.12 No.4