Viability and Adhesion of Periodontal Ligament Fibroblasts on a Hydroxyapatite Scaffold Combined with Collagen, Polylactic Acid-Polyglycolic Acid Copolymer and Platelet-Rich Fibrin: A Preclinical Pilot Study.

Background: Conventional periodontal therapy relies on bone regeneration strategies utilizing scaffolds made of diverse materials, among which collagen, to promote cell adhesion and growth. Objective: To evaluate periodontal ligament fibroblast (HPdLF) cell adhesion and viability for periodontal regeneration purposes on hydroxyapatite scaffolds containing collagen (HAp-egg shell) combined with polylactic acid−polyglycolic acid copolymer (PLGA) and Platelet-Rich Fibrin (PRF). Methods: Four variations of the HAp-egg shell were used to seed HPdLF for 24 h and evaluate cell viability through a live/dead assay: (1) (HAp-egg shell/PLGA), (2) (HAp-egg shell/PLGA + collagen), (3) (HAp-egg shell/PLGA + PRF) and (4) (HAp-egg shell/PLGA + PRF + collagen). Cell adhesion and viability were determined using confocal microscopy and quantified using central tendency and dispersion measurements; significant differences were determined using ANOVA (p < 0.05). Results: Group 1 presented low cell viability and adhesion (3.70−10.17%); groups 2 and 3 presented high cell viability and low cell adhesion (group 2, 59.2−11.1%, group 3, 58−4.6%); group 4 presented the highest cell viability (82.8%) and moderate cell adhesion (45%) (p = 0.474). Conclusions: The effect of collagen on the HAp-egg shell/PLGA scaffold combined with PRF favored HPdLF cell adhesion and viability and could clinically have a positive effect on bone defect resolution and the regeneration of periodontal ligament tissue.

Oxidative Stress in ICU Patients: ROS as Mortality Long-Term Predictor.

Lipid peroxidation, protein oxidation, and mutations in mitochondrial DNA generate reactive oxygen species (ROS) that are involved in cell death and inflammatory response syndrome. ROS can also act as a signal in the intracellular pathways involved in normal cell growth and homeostasis, as well as in response to metabolic adaptations, autophagy, immunity, differentiation and cell aging, the latter of which is an important characteristic in acute and chronic pathologies. Thus, the measurement of ROS levels of critically ill patients, upon admission, enables a prediction not only of the severity of the inflammatory response, but also of its subsequent potential outcome. The aim of this study was to measure the levels of mitochondrial ROS (superoxide anion) in the peripheral blood lymphocytes within 24 h of admission and correlate them with survival at one year after ICU and hospital discharge. We designed an observational prospective study in 51 critical care patients, in which clinical variables and ROS production were identified and correlated with mortality at 12 months post-ICU hospitalization. Oxidative stress levels, measured as DHE fluorescence, show a positive correlation with increased long-term mortality. In ICU patients the major determinant of survival is oxidative stress, which determines inflammation and outlines the cellular response to inflammatory stimuli.

Elaboration and Biocompatibility of an Eggshell-Derived Hydroxyapatite Material Modified with Si/PLGA for Bone Regeneration in Dentistry.

Hydroxyapatite (HAp) is the most commonly used biomaterial in modern bone regeneration studies because of its chemical similarity to bone, biocompatibility with different polymers, osteoconductivity, low cost, and lack of immune response. However, to overcome the disadvantages of HAp, which include fragility and low mechanical strength, current studies typically focus on property modification through the addition of other materials. Objective. To develop and evaluate the biocompatibility of a HAp material extracted from eggshells and modified with silicon (Si) and poly(lactic-co-glycolic) acid (PLGA). Materials and Methods. An in vitro experimental study in which a HAp material prepared from eggshells was synthesized by wet chemical and conventional chemical precipitation. Subsequently, this material was reinforced with Si/PLGA using the freezing/lyophilization method, and then osteoblast cells were seeded on the experimental material (HAp/Si/PLGA). To analyse the biocompatibility of this composite material, scanning electron microscopy (SEM) and fluorescence confocal microscopy (FCM) techniques were used. PLGA, bovine bone/PLGA (BB/PLGA), and HAp/PLGA were used as controls. Results. A cellular viability of 96% was observed for the experimental HAp/Si/PLGA material as well as for the PLGA. The viability for the BB/PLGA material was 90%, and the viability for the HAp/PLGA was 86%. Cell adhesion was observed on the exterior surface of all materials. However, a continuous monolayer and the presence of filopodia were observed over both external and internal surface of the experimental materials. Conclusions. The HAp/Si/PLGA material is highly biocompatible with osteoblastic cells and can be considered promising for the construction of three-dimensional scaffolds for bone regeneration in dentistry.

Analysis of In Vitro Osteoblast Culture on Scaffolds for Future Bone Regeneration Purposes in Dentistry.

One of the main focuses of tissue engineering is to search for tridimensional scaffold materials, complying with nature's properties for tissue regeneration. Determining material biocompatibility is a fundamental step in considering its use. Therefore, the purpose of this study was to analyze osteoblast cell adhesion and viability on different materials to determine which was more compatible for future bone regeneration. Tridimensional structures were fabricated with hydroxyapatite, collagen, and porous silica. The bovine bone was used as material control. Biocompatibility was determined by seeding primary osteoblasts on each tridimensional structure. Cellular morphology was assessed by SEM and viability through confocal microscopy. Osteoblast colonization was observed on all evaluated materials' surface, revealing they did not elicit osteoblast cytotoxicity. Analyses of four different materials studied with diverse compositions and characteristics showed that adhesiveness was best seen for HA and viability for collagen. In general, the results of this investigation suggest these materials can be used in combination, as scaffolds intended for bone regeneration in dental and medical fields.

Antimicrobial Activity of Piper marginatum Jacq and Ilex guayusa Loes on Microorganisms Associated with Periodontal Disease.

BACKGROUND: Chronic periodontitis is a multifactorial infectious disease, where multiple bacteria, such as Porphyromonas gingivalis, Prevotella intermedia, and Fusobacterium nucleatum are implicated. The main purpose of researching natural products is to find substances or compounds with antimicrobial activity. AIM: The objective of this work was to determine antimicrobial activity from extracts and obtained fractions from Piper marginatum Jacq and Ilex guayusa Loes on P. gingivalis ATCC 33277, F. nucleatum ATCC 25586, and P. intermedia ATCC 25611. METHODS: Total ethanol extracts were obtained from both plants. Fractions were obtained from total ethanol extracts with amberlite as a stationary phase employing hexane, acetone, and ethanol-water as solvents. Qualitative and quantitative phytochemical characterization was performed on total ethanol extracts from both plants. Antimicrobial activity from total ethanol extracts and fractions from both plants were evaluated on P. gingivalis ATCC 33277, F. nucleatum ATCC 25586, and P. intermedia ATCC by the well diffusion method with Wilkins-Chalgren agar. RESULTS: Piper marginatum Jacq total ethanol extract presented antimicrobial activity against all three bacteria, whereas Ilex guayusa Loes was only efficient against P. gingivalis ATCC 33277 and P. intermedia ATCC 25611, with inhibition halos from 9.3 to 30 mm. Ilex guayusa Loes obtained fractions presented antimicrobial activity against all three microorganisms evaluated, with inhibition halos ranging from 9.7 to 18.7 mm. In regards to Piper marginatum Jacq fractions, inhibition halos were between 8.3 and 19 mm, against all three microorganisms evaluated; only hexane fraction did not present antimicrobial activity against F. nucleatum ATCC 25586. CONCLUSION: Piper marginatum Jacq and Ilex guayusa Loes total ethanol extracts and fractions presented outstanding antimicrobial activity against P. gingivalis ATCC 33277, P. intermedia ATCC 25611, and F. nucleatum ATCC 25586.

Determining the effectiveness of Candida guilliermondii in the biological control of Rhizopus stolonifer in postharvest tomatoes / Determinación de la efectividad del control biológico de Rhizopus stolonifer en tomates poscosecha utilizando candida guilliermondii / Determinação da efetividade do controlo biológico de Rhizopus stolonifer em tomates poscosecha utilizando candida guilliermondii

Las alteraciones de frutos de tomate poscosecha por causas microbiológicas conllevan a su deterioro fisiológico produciendo su descomposición. En este estudio, Candida guilliermondii fue examinada en ensayos in vitro e in vivo para determinar su eficacia en el control biológico contra Rhizopus stolonifer en tomates (Lycopersicon esculentum). El efecto antagónico se llevo a cabo usando biomasa de la levadura y sus metabolitos los cuales se identificados en un cromatógrafo gases-masas. Los ensayos in vitro mostraron que la única fase con respuesta antagónica al patógeno fue la fase acuosa sin filtrar. En los ensayos in vivo, la biomasa de Candida guilliermondii presento el mayor porcentaje de protección contra el patógeno (87 %) en comparación con la fase acuosa sin filtrar y la fase orgánica sin concentrar que presentaron el 77 y 80 % de protección respectivamente. Estos resultados son de gran importancia para evitar las perdidas económicas además de garantizar un tiempo de vida mas largo del tomate asegurando una mejor distribución del producto y evitando sus perdidas en estos tiempos de crisis alimentaria en especial en países en desarrollo.

Post-harvest losses in tomato crops can be accredited to a number of causes, which include biological causes that produce physiological deterioration; infection caused by diseases and pests that cause rotting. In this study, we assayed, in vitro and in vivo, the yeast Candida guilliermondii to determine its effectiveness as a biocontrol to reduce the rotting produced by Rhizopus stolonifer on tomatoes (Lycopersicon esculentum). The antagonistic effect was tested using a yeast biomass suspension; gas chromatography and a mass selective detector were used to identify its metabolites. According to the in vitro test, the only phase with an antagonistic response against Rhi%opus stolonifer was the unfiltered water phase. In the in vivo tests, the biomass of Candida guilliermondii presented the highest percentage of protection of the tomato (87 %) compared with the unfiltered aqueous phase and the unconcentrated organic phase, which reached only 77 and 80 % respectively. These results are essential to avoid economic losses caused by fungi and to increase the shelf life of tomatoes improving the distribution of the product and preventing postharvest losses in this time of food crises, especially in developing countries.

As perdas pós-colheita de frutos de tomate são creditadas em várias fontes, incluindo causas biológicas que levam ao deterioro fisiológico e infecção por doenças e pragas que podem levar à sua decomposição. Neste estudo, a levedura Candidaguilliermondii foi examinada in vitro e in vivo para determinar a sua eficácia no controlo biológico de Rhizopus stolonifer em tomates (Lycopersicon esculentum). O efeito antagonista realizou-se utilizando biomassa de levedura e os seus metabolitos, os quais foram identificados por cromatografia gasosa acoplada a um detector selectivo de massa. Os ensaios in vitro mostraram que a única fase com resposta antagonista a Rhizopus stolonifer foi a fase aquosa não filtrada. Nos ensaios in vivo, a biomassa Candida guilliermondii teve a maior percentagem de protecção contra o patógeno (87%) em comparação com a fase aquosa não filtrada e a fase orgânica não concentrada apresentando 77 e 80 % de protecção, respectivamente. Estes resultados são muito importantes para evitar perdas económicas causadas por fungos, além de garantir ao tomate uma vida útil mais longa, o que assegura uma melhor distribuição do produto e evita perdas pós-colheita neste momento de crise alimentar, especialmente nos países em desenvolvimento.

Chemical and microbiological comparison of biodeterioration inColombian heritage constructions / Comparación química y microbiológica del biodeterioro en construcciones patrimoniales en Colombia

Se compararon química y microbiológicamente morterosde Bogotá, Villa de Leyva y Barichara. Las muestras seanalizaron por espectrometría de absorción y emisión atómica,espectroscopia infrarroja con transformada de Fourier,difracción de Rayos X, microscopía electrónica de barrido yespectroscopia por dispersión de energía. Se encontraron óxidosde silicio, aluminio, calcio, hierro, magnesio, yeso, weddellita,despuljosita, cuarzo, berlinita, carbonatos, mica, feldespatos,silicatos, sales de nitratos, sulfitos y compuestos orgánicos.A su vez, se hallaron partículas irregulares entre 10, 50 y 100µm y fibras de tipo orgánico de 20 µm. Se realizó el conteo deunidades formadoras de colonias por el método de dilucionespara identificar microorganismos fúngicos. Se identificaron lossiguientes géneros Aspergillus, Penicillium, Alternaria, Fusarium,Mucor y Syncephalastrum. La muestra de Bogotá presentó el mayornúmero de UFC/mL y el mayor porcentaje de humedad relativa.La concentración de hongos en esta muestra, a diferencia delas de Villa de Leyva y de Barichara, causó la degradación de lamayoría de los metales identificados. Esta comparación químicay microbiológica propone un plan eficaz de intervención paraeliminar y prevenir el biodeterioro en apoyo a la conservación deobras patrimoniales...

Mortars from Bogotá, Villa de Leyvaand Barichara were compared chemically andmicrobiologically. We analyzed the samples using atomicabsorption and emission spectrometry, Fourier-transforminfrared spectroscopy, X-ray diffraction, scanningelectron microscopy and energy dispersive spectroscopy.Oxides of silicon, aluminum, calcium, iron, magnesium,gypsum, weddellite, despujolsite, quartz, berlinite,carbonate, mica, feldspars, silicates, nitrate salts, sulfites,and organic compounds were identified. In addition,irregular particles between 10, 50 an 100 µm werefound, as well organic fibers of 20 µm. Was performeda CFU count using a dilution method to identify fungalmicroorganisms and found following genera Aspergillus,Penicillium, Alternaria, Fusarium, Mucor and Syncephalastrum.The mortar sample taken in Bogotá presented thehighest number of CFU/mL and the highest percentageof relative humidity. The concentration of fungi in thissample, unlike those from Villa de Leyva and Barichara,caused degradation in most of the metals identified.This chemical and microbiological comparison proposesan effective plan of action to eliminate and preventbiodeterioration in support of the conservation ofheritage constructions...

As amostras foram analisadas por espectrometria deemissão e espectroscopia de absorção atômica, infravermelhocom transformada de Fourier, difração de raios X, microscopiaeletrônica de varredura e espectroscopia de energia dispersiva.Foram identificados óxidos de silício, alumínio, cálcio, ferro,magnésio, gesso, weddellita, despuljosita, quartzo, berlinita,carbonato, mica, feldspato, silicatos, sais de nitratos, sulfitos, ecompostos orgânicos. Partículas irregulares entre os 10, 50 e 100µm foram encontradas bem como fibras de tipo orgânico de20 µm. Realizou-se uma contagem CFU usando um método dediluição para identificar microorganismos fúngicos e encontrousefungos dos gêneros Aspergillus, Penicillium, Alternaria, Fusarium,Mucor e Syncephalastrum. A amostra de Bogotá apresentou o maiornúmero de UFC/mL e umidade relativa do ar. A maior presençade fungos desta amostra, ao contrário das amostras da Villa deLeyva e Barichara, causou degradação na maioria dos metaisidentificados. Esta comparação química e microbiológica podesugerir um plano de ação eficaz para a eliminação e prevenção dabiodegradação e assim preservar obras patrimoniais.Departamento de Química, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Microbiología, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Biología, Facultad de Ciencias. PontificiaUniversidad Javeriana. Bogotá, D.C., Colombia.Departamento de Arquitectura, Facultad de Arquitectura y Diseño.Pontificia Javeriana. Bogotá, D.C., Colombia.Received: 15-12-2012 Accepted: 02-02-2013 Published on line: 28-02-2013 Edited by Alberto Acosta mUniversitas Scientiarum, Journal of the Faculty of Sciences, Pontificia Universidad Javeriana, is licensed under the Creative Commons 2.5 of Colombia: Attribution - Noncommercial - No Derivative...