Update on Bone Grafting Materials Used in Dentistry in the Bone Healing Process: Our Experience from Translational Studies to Their Clinical Use

The use of bone grafts is important to preserve the alveolar bone ridge height and volume indispensable for dental implant placement. Despite the highly successful outcomes for the implant-supported overdentures, it seems that a majority of edentulous individuals have not pursued implant-based rehabilitation. Among the reasons cited for this, discrepancy between highly successful therapy and its acceptance is the cost of the treatment. Therefore, the development of biomaterials for bone grafting with comparable characteristics and biological effects than those renowned internationally is necessary. In addition, domestic manufacture would reduce the high costs in public health arising from the application of these biomaterials in the dental field. The aim of the following chapter is to offer an update on one bone grafting material frequently used in dentistry through an assessment of anorganic bovine bone graft in small and medium experimental models as well as its clinical use

Effect of deforestation and subsequent land use management on soil carbon stocks in the South American Chaco

The subhumid Chaco region of Argentina, originally covered by dry sclerophyll forest, has been subjected to clearing since the end of the 1970s and replacement of the forest by no-till farming. Land use changes produced a decrease in aboveground carbon (C) stored in forests, but little is known about the impact on soil organic C stocks. The aim of this study was to evaluate soil C stocks and C fractions up to 1&thinsp;m depth in soils under different land use:  &lt; 10-year continuous cropping,  &gt; 20-year continuous cropping, warm-season grass pasture and native forest in 32 sites distributed over the Chaco region. The organic C stock content up to 1&thinsp;m depth expressed as equivalent mass varied as follows: forest (119.3&thinsp;Mg&thinsp;ha−1)&thinsp; &gt; &thinsp;pasture (87.9&thinsp;Mg&thinsp;ha−1)&thinsp; &gt; &thinsp;continuous cropping (71.9 and 77.3&thinsp;Mg&thinsp;ha−1), with no impact of the number of years under cropping. The coarse particle fraction (2000–212&thinsp;µm) at 0–5 and 5–20&thinsp;cm depth layers was the most sensitive organic carbon fraction to land use change. Resistant carbon ( &lt; 53&thinsp;µm) was the main organic matter fraction in all sample categories except in the forest. Organic C stock, its quality and its distribution in the profile were responsive to land use change. The conversion of the Chaco forest to crops was associated with a decrease of organic C stock up to 1&thinsp;m depth and with the decrease of the labile fraction. The permanent pastures of warm-season grasses allowed higher C stocks to be sustained than cropping systems and so could be considered a sustainable land use system in terms of soil C preservation. As soil organic C losses were not restricted to the first few centimetres of the soil, the development of models that would allow the estimation of soil organic C changes in depth would be useful to evaluate the impact of land use change on C stocks with greater precision.</p

Large-scale patterns of turnover and basal area change in Andean forests

General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century

In-site interaction evaluation of Tn density by inhibition/competition assays

The tumor-associated structure N-acetyl-galactosamine-O-Ser/Thr (Tn antigen), which is overexpressed in various tumor cell types, notably of the breast, ovary and colon, is an interesting determinant that is useful for cancer diagnosis and follow-up. The aim of this research was to study different assay strategies in order to determine the most sensitive system for further application in epitope characterization and binding assessment. The tetrameric isolectin obtained from Vicia villosa seeds (VVLB4) shows high affinity for the tumor-associated structure. A monoclonal antibody against VVLB4, MabVV(34), was generated, and the interaction between MabVV(34) and VVLB4 was studied by means of binding and inhibition assays. Several synthetic peptides (10 amino acid sequences) designed from the amino acid sequence of VVLB4 and obtained from trypsin digestion were tested to determine which amino acids were involved in the interaction between MabVV(34) and VVLB4. The further unraveling of this epitope was investigated by inhibition using designed synthetic peptides as well as mixtures mimicking variable density effect. Under the experimental circumstances, MabVV(34) was able to inhibit the binding of VVLB4 to Tn. Two of the four peptide sequences assayed showed better inhibition properties. Finally, mixtures containing these selected sequences allowed the evaluation of binding and inhibition as a function of Tn density. We conclude that the present study facilitates the further development of a specific Tn marker and may contribute to the development of Tn-like radiolabelled peptides or Tn-specific radiolabelled fragments providing a highly selective tool for cancer diagnosis and treatment. This strategy may contribute to characterize the new generation of radiopharmaceuticals for diagnosis and therapy based on biomolecules like antibodies, fragments or peptides, whose application is directly guided by their specific molecular recognition. (C) 2010 Published by Elsevier Inc.Radiolog

Un nuevo método para la evaluación de la sustentabilidad agropecuaria en la provincia de Salta, Argentina

En este trabajo se describe una experiencia de diseño, desarrollo y cálculo de un índice de evaluación de la sustentabilidad agropecuaria. Este índice, que se denominó ISAP (Índice de Sustentabilidad Agropecuaria), se estimó en siete establecimientos agropecuarios del departamento de Anta de la provincia de Salta, en el noroeste de Argentina. El ISAP se construyó mediante la estimación de indicadores previamente seleccionados de manera conjunta con los productores agropecuarios locales durante tres series de encuestas estructuradas y semiestructuradas realizadas entre los años 2012 y 2014. El ISAP se construyó sobre el concepto de “sistema socioecológico”, entendido como el ámbito geográfico y cultural en el cual se producen los procesos de cambio social, ambiental y productivo. Este enfoque permitió incluir en la evaluación indicadores que describen los procesos de gobernanza y toma de decisiones de gestión. El cálculo del ISAP se realizó con la participación activa de los productores agropecuarios, quienes fueron los responsables de la evaluación de sus propios establecimientos. Los establecimientos evaluados presentaron un nivel aceptable de sustentabilidad, superando el umbral de aceptabilidad establecido para este estudio. Un análisis detallado de cada caso permitió identificar aspectos que requieren intervenciones y sugerir algunas estrategias de mejora. La versión actual del ISAP será discutida con productores y expertos locales para evaluar su aplicabilidad en otros sistemas productivos y en otras regiones de la provincia de Salta o del resto del noroeste argentino. El ISAP no pretende reemplazar otras metodologías de evaluación, sino que puede ser una herramienta de análisis complementaria para evaluar y optimizar el nivel de sustentabilidad de los establecimientos agropecuarios de la región.This paper describes the design, development, and calculation of an index to assess agricultural sustainability. This index was called ISAP (a Spanish acronym meaning Agricultural Sustainability Index) and was estimated for seven farms in the Anta Department, province of Salta, Northwestern Argentina. The construction of the ISAP involved the estimation of indicators that where previously selected together with agricultural producers during three series or structured and semi-structured interviews performed between 2012 and 2014. The ISAP was built on the concept of “social-ecological system”, understood as the geographical and cultural arena where processes of social, environmental, and productive change can take place. This approach allowed the inclusion of governance and decision-making processes in the assessment. The calculation of the ISAP was made with the active participation of farmers, who where in charge of assessing their own establishments. The farms assessed present an acceptable level of sustainability, all above the acceptability threshold adopted for this study. A detailed analysis of the cases studied allowed the identification of aspects that need interventions and improvement strategies. The current version of the ISAP will be discussed with local experts and producers to assess its potential applicability to other production systems, and for different areas in the province of Salta or in other parts of Northwestern Argentina. The ISAP is not meant to replace other assessment methods but aims to be a complementary tool to assess and optimize the level of agricultural sustainability in the region.Fil: Vega, M. L.. Universidad Nacional de Salta; ArgentinaFil: Iribarnegaray, Martín Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Hernandez, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Arzeno, José Luis. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Osinaga, R.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Zelarayán, A. L.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Fernández, D. R.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Mónico Serrano, F. H.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Volante, J. N.. Instituto Nacional de Tecnología Agropecuaria; ArgentinaFil: Seghezzo, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta. Instituto de Investigaciones en Energía no Convencional; Argentin

An Echinococcus multilocularis coproantigen is a surface glycoprotein with unique O-gycosylation

A major surface constituent of Echinococcus multilocularis adult worms, referred to as EmA9 antigen, was immunoaffinity purified and identified as a high molecular weight glycoconjugate. Labelling studies using the monoclonal antibody MAbEmA9 indicated that this antigen undergoes a regulated expression during the development from the larval to the adult parasite. Chemical modification of carbohydrate by periodate oxidation resulted in a reduced reactivity with antigen specific antibodies. Non-reductive beta-elimination of the purified molecule indicated the presence of O-linked glycans attached to threonine residues. Carbohydrate compositional analyses indicated the presence of N- and O-glycans with the ratio of carbohydrate to protein being 1.5:1 (w/w). N- and O-linked glycans were released by hydrazinolysis and analysed as 2-aminobenzamide derivatised glycans by mass spectrometry together with HPLC and enzymatic sequencing. Novel linear O-linked saccharides with multiple beta-HexNAc extensions of reducing end Gal were identified. N-linked glycans were also detected with oligomannose and mono-, bi-, tri- and tetra-antennary type structures, most of which were found to be core-fucosylated. Taken together, the results indicate that the EmA9 antigen is a glycoprotein located at the outer surface of the adult E. multilocularis. The observation that the EmA9 antigen expression is developmentally regulated suggests an involvement of this glycoprotein in the establishment of the parasite in its canine host

Sleep Duration is Inversely Associated with Serum Uric Acid Concentrations and Uric Acid to Creatinine Ratio in an Elderly Mediterranean Population at High Cardiovascular Risk

The aim of the study was to evaluate sleep duration and sleep variability in relation to serum uric acid (SUA) concentrations and SUA to creatinine ratio. This is a cross-sectional analysis of baseline data from 1842 elderly participants with overweight/obesity and metabolic syndromein the (Prevención con Dieta Mediterránea) PREDIMED-Plus trial. Accelerometry-derived sleep duration and sleep variability were measured. Linear regression models were fitted to examine the aforementioned associations. A 1 hour/night increment in sleep duration was inversely associated with SUA concentrations (β = 0.07, p = 0.047). Further adjustment for leukocytes attenuated this association (p = 0.050). Each 1-hour increment in sleep duration was inversely associated with SUA to creatinine ratio (β = 0.15, p = 0.001). The findings of this study suggest that longer sleep duration is associated with lower SUA concentrations and lower SUA to creatinine ratio