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

Bioassay-guided fractionation in Anacardium excelsum (bert. & balb. ex kunth) skeels (anacardiaceae)

Anacardium excelsum is a tree between 15 and 50 meters high, with a thick trunk and is present in some departments of Colombia. Its nut-shaped fruits were used in the old Upar Valley by natives (Valledupar) to make Caracolí bread. Most research has been done at the forest level, but there are few phytochemical and biological activity studies. This bioguided work shows the application of antioxidant methods (ABTS+•, DPPH• and DMPD+•) in the search for active compounds present in the fraction and subfractions of greater activity. The antioxidant capacity was measured to the crude extract in ethanol and the antioxidant activity of the fractions in petroleum ether, dichloromethane, and ethanol-butanol of testa, tegument, flower, fruit, seed, bark, and leaf. Column Chromatography, Thin Layer Chromatography and Gas Chromatography coupled to Mass Spectrometry were performed on the petroleum ether fraction of testa with greater antioxidant capacity, finding the following compounds: 3- pentadec(en)il-phenol, 3-pentadecyl-phenol, 3-heptadeca(dien)il-phenol, 3-heptadec(en)ilphenol, 3-heptadecyl-phenol, 3-nonadec(en)il-phenol, ethyl ester of hexadecanoic acid, ethyl ester of heptadecanoic acid , ethyl ester of linolenic acid, hexadecanoic acid butyl ester, ethyl ether of octadecanoic acid, ethyl ester of (Z)-9-octadecenoic acid, ethyl ester of 9,12- octadecadienoic acid and ethyl ester of eicosanoic acid. The results indicate that Anacardium excelsum is a potential source of bioactive compounds.Incluye referencias bibliográfica

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

null

Se compararon química y microbiológicamente morteros en Bogotá, Villa de Leyva y Barichara. Las muestras se analizaron por espectrometría de absorción y emisión atómica, espectroscopia infrarroja con transformada de Fourier, difracción de Rayos X, microscopía electrónica de barrido y espectroscopia por dispersión de energía. Se realizó el conteo de UFC por el método de diluciones, para luego identificar los microorganismos fúngicos. Se encontraron óxidos de silicio, aluminio, calcio, hierro, magnesio, yeso, weddellita, despuljosita, cuarzo, berlinita, carbonatos, mica, feldespatos, silicatos, sales de nitratos, sulfitos y compuestos orgánicos. Se encontraron partículas irregulares entre 10, 50 y 100 µm y fibras de tipo orgánico de 20 µm. Se identificaron los géneros fúngicos Aspergillus, Penicillium, Alternaria, Fusarium, Mucor y Syncephalastrum. La muestra de Bogotá presentó el mayor número de UFC/mL y humedad relativa a diferencia de Villa de Leyva y Barichara. La mayor presencia de hongos en Bogotá se evidenció por la degradación de la mayoría de los metales identificados. Esta comparación química y microbiológica puede sugerir un plan eficaz de intervención para la eliminación y prevención del biodeterioro y así conservar obras patrimoniales.nul

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

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 Rhizopus 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.

Determining the effectiveness of Candida guilliermondii in the biological control of Rhizopus stolonifer in postharvest tomatoes

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 Rhizopus 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.