Cytocompatibility, cytotoxicity and genotoxicity analysis of dental implants

Several types of materials are frequently used for dental prostheses in dental medicine. Different treatments with titanium are the most used. The aim of the present study was to analyze by means of cytotoxicity and cytocompatibility techniques the capacity of dental implants to integrate to the bone tissue. Cultures of UMR 106 cell line derived from an osteosarcoma were used for bioassays mainly because they show many of the properties of osteoblasts. Dental implant samples provided by B&W company were compared with others of recognized trademarks. The first ones contain ASTM titanium (8348 GR2) with acid printing. Cytotoxicity was analyzed by means of lysosome activity, using the neutral red technique and alkaline phosphatase enzyme activity. Cell variability was determined by means of the acridine ethidium-orange bromide technique. One-way ANOVA and Bonferroni and Duncan post-ANOVA tests were used for the statistical analysis. The assays did not show significant differences among the dental implants analyzed. Our findings show that the dental prostheses studied present high biocompatibility, quantified by the bioassays performed. The techniques employed revealed that they can be a useful tool for the analysis of other materials for dental medicine use.Instituto Multidisciplinario de Biología Celula

Can we validate a clinical score to predict the risk of severe infection in patients with systemic lupus erythematosus? A longitudinal retrospective study in a British Cohort

OBJECTIVE: Severe infections are a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Our primary objective was to use data from a large Spanish cohort to develop a risk score for severe infection in SLE, the SLE Severe Infection Score (SLESIS) and to validate SLESIS in a separate cohort of 699 British patients. DESIGN AND SETTING: Retrospective longitudinal study in a specialist tertiary care clinic in London, UK. PARTICIPANTS: Patients fulfilling international classification criteria for SLE (n=209). This included 98 patients who had suffered severe infections (defined as infection leading to hospitalisation and/or death) and 111 randomly selected patients who had never suffered severe infections. OUTCOMES: We retrospectively calculated SLESIS at diagnosis for all 209 patients. For the infection cases we also calculated SLESIS just prior to infection and compared it to SLESIS in 98 controls matched for disease duration. We carried out receiver operator characteristic (ROC) analysis to quantify predictive value of SLESIS for severe infection. RESULTS: Median SLESIS (IQR) at diagnosis was higher in the infection group than in the control group (4.27 (3.18) vs 2.55 (3.79), p=0.0008). Median SLESIS prior to infection was higher than at diagnosis (6.64 vs 4.27, p<0.001). In ROC analysis, predictive value of SLESIS just before the infection (area under the curve (AUC)=0.79) was higher than that of SLESIS at diagnosis (AUC=0.63). CONCLUSIONS: We validated the association of SLESIS with severe infection in an independent cohort. Calculation of SLESIS at each clinic visit may help in management of infection risk in patients with SLE. Prospective studies are needed to confirm these findings

Atividades iniciais para validação de método analítico para quantificação de betacaroteno no colostro de vacas.

Os carotenoides, mais especificamente o betacaroteno, são de suma importância para todos os animais. Isso porque, esses compostos são precursores da vitamina A ou apenas provitamina A, ou seja, será originada vitamina A partir da síntese desses carotenoides, vitamina esta, que possui grande relevância. Tomando por base o que foi citado, a quantificação dos carotenoides se torna uma importante avaliação, para poder identificar a concentração dos mesmos, de modo a aferir se o indivíduo está sofrendo um déficit ou não, e casa haja baixas concentrações, adotar as devidas estratégias de correção, para que não ocorre nenhum tipo de prejuízo em longo prazo ao animal. Contudo, o principal meio para coleta de amostra para quantificação dos carotenoides ainda é por meio da coleta de sangue, o que gera estresse e desconforto ao animal e, com isso, novas alternativas para a coleta vem sendo pesquisadas com o intuito de prover bem estar ao animal

The grapevine uncharacterized intrinsic protein 1 (VvXIP1) is regulated by drought stress and transports glycerol, hydrogen peroxide, heavy metals but not water

A MIP (Major Intrinsic Protein) subfamily called Uncharacterized Intrinsic Proteins (XIP) was recently described in several fungi and eudicot plants. In this work, we cloned a XIP from grapevine, VvXIP1, and agrobacterium-mediated transformation studies in Nicotiana benthamiana revealed that the encoded aquaporin shows a preferential localization at the endoplasmic reticulum membrane. Stopped-flow spectrometry in vesicles from the aqy-null yeast strain YSH1172 overexpressing VvXIP1 showed that VvXIP1 is unable to transport water but is permeable to glycerol. Functional studies with the ROS sensitive probe CM-H(2)DCFDA in intact transformed yeasts showed that VvXIP1 is also able to permeate hydrogen peroxide (H2O2). Drop test growth assays showed that besides glycerol and H2O2, VvXIP1 also transports boric acid, copper, arsenic and nickel. Furthermore, we found that VvXIP1 transcripts were abundant in grapevine leaves from field grown plants and strongly repressed after the imposition of severe water-deficit conditions in potted vines. The observed downregulation of VvXIP1 expression in cultured grape cells in response to ABA and salt, together with the increased sensitivity to osmotic stress displayed by the aqy-null yeast overexpressing VvXIP1, corroborates the role of VvXIP1 in osmotic regulation besides its involvement in H2O2 transport and metal homeostasis.This work was supported by European Union Funds (FEDER/COMPETE Operational Competitiveness Programme) and Portuguese national Funds (FCT-Portuguese Foundation for Science and Technology): KBBE-2012-6-3117 "Inovinne", FCOMP-01-0124-FEDER-022692 and PTDC/AGR-ALI/100636/2008. HN (SFRH/BD/74257/2010) and APM (SFRH/BD/65046/2009) were supported by PhD grants from FCT. The Interuniversity Attraction Poles Programme-Belgian Science Policy (IAP7/29) and the Belgian French community ARC11/16-036 project.info:eu-repo/semantics/publishedVersio

Evidence for an Allelopathic Interaction Between Rye and Wild Oats

Allelopathy is a biological phenomenon in which an organism produces one or more biochemicals that influence the growth, survival, and reproduction of other organisms. Allelopathy has been the subject of a great deal of research in chemical ecology since the 1930s. The characterization of the factors that influence this phenomenon has barely been explored, mainly due to the complexity of this area. The main aim of the research carried out to date has been to shed light on the importance of these interactions in agroecosystems, especially in relation to the interactions between crops and weeds. Herein we report the characterization of a complete allelochemical pathway involving benzoxazinones, which are known to participate in allelopathic plant defense interactions of several plants of high agronomic interest. The production of the defense chemicals by a donor plant (crop), the route and transformations of the chemicals released into the environment, and the uptake and phytotoxic effects on a target plant (weed) were all monitored. The results of this study, which is the first of its kind, allowed a complete dynamic characterization of the allelopathic phenomenon for benzoxazinones

Germination response of common annual and perennial forbs to heat shock and smoke treatments in the Chaco Serrano, central Argentina

Fire is a key ecological factor affecting plant dynamics. In the last few decades, fire occurrence in the Chaco region has increased noticeably, challenging the adaptive capacity of plants to regenerate after a fire. Broad-leaved forb species have been much less studied than woody and graminoids, although they are an important component of fire dynamics. Here we analysed the germination response to heat shock of 70 and 110°C, smoke and their combination in 10 broad-leaved herbaceous species frequently occurring in the Chaco Serrano of Córdoba province, central Argentina, including five annual (Bidens subalternans, Conyza bonariensis, Schkuhria pinnata, Tagetes minuta and Zinnia peruviana) and five perennial species (Borreria eryngioides, Sida rhombifolia, Solidago chilensis, Taraxacum officinale and Verbena litoralis). We also compared the response of annual versus perennial species. Six species had highest germination when treated with heat and smoke combined, whereas two had lowest germination under this treatment, indicating synergistic and antagonistic interaction of these factors respectively. Most of the species tolerated heat shock (i.e. germination was similar to that in control treatment), whereas others had higher germination in response to heat shock, especially under the moderate 70°C treatment. Germination was higher than control (i.e. no heat and no smoke) after smoke treatment in four species. Perennial species showed higher average germination than annuals in both heat treatments and in the control. Annual species had higher average germination for all treatments involving smoke. The high variability observed at the species level, and the limited number of species studied calls for precaution in interpreting and extrapolating results. Nevertheless, our study shows a general positive response of both perennial and annual species to fire cues, suggesting an advantage of these species for colonizing post-fire environments, and being favoured under scenarios of increasingly frequent low-to-medium intensity fires.Fil: Arcamone, Julieta Rocío. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Diversidad Biológica y Ecológica. Cátedra de Ecología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Jaureguiberry, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin