Skin transcriptome analysis in Brangus cattle under heat stress.

Heat stress is a major factor that negatively affects animal welfare and production systems. Livestock should adapt to tropical and subtropical areas and to meet this, composite breeds have been developed. This work aimed to evaluate gene expression profiles in the skin of Brangus cattle under heat stress using a case-control design, and to correlate this with skin histological characteristics. Two groups of bulls were set using rectal temperature as a criterion to define stress conditions: stressed (N = 5) and non-stressed (N = 5) groups. Skin transcriptomics was performed and correlations between breed composition, phenotypic and skin histological traits were evaluated. Results showed 4309 differentially expressed genes (P < 0.01), 2113 downregulated and 2196 upregulated. Enrichment and ontology analyses revealed 132 GO terms and 67 pathways (P < 0.01), including thermogenesis, glycolysis, gluconeogenesis, mitochondrial activity, antioxidant and immune response, and apoptosis. The identity of the terms and pathways indicated the diversity of mechanisms directed to relieve the animals' suffering, acting from simple passive mechanisms (conduction, convection and radiation) to more complex active ones (behavioural changes, evaporation, vasodilation and wheezing). Furthermore, significant differences between phenotypic and skin histological traits and correlations between pairs of traits suggested a direction towards heat dissipation processes. In this sense, number of vessels was positively correlated with number of sweat glands (P < 0.001) and both were positively correlated with zebuine genetic content (P < 0.05 and P < 0.01, respectively), gland size was positively correlated with epidermal thickness and negatively with hair length (P < 0.05), and epidermal thickness was negatively correlated with gland-epidermis distance (P < 0.0005). These results support the notion that response to heat stress is physiologically complex, producing significant changes in the expression of genes involved in several biological pathways, while the animal's ability to face it depends greatly on their skin features.

Assessment of probiotic properties of lactic acid bacteria isolated from an artisanal Colombian cheese.

Lactic Acid Bacteria play an important role in the milk fermentation processes of traditional cheeses and have become an important target for the development of novel cheese cultures because of their ability to confer health benefits. This study aimed to evaluate the probiotic potential of 12 Lactic Acid Bacteria (LAB) strains previously isolated and molecularly identified from an artisanal Colombian Double-Cream Cheese. Probiotic properties, including safety (hemolysis and sensibility to antibiotics), pH and bile salt tolerance, auto-aggregation, cell surface hydrophobicity, antibacterial activity, and exopolysaccharide production, were examined. None of the strains were hemolytic, and Pediococcus (16, 18) and Lactobacillus (28, 29) were found to be sensitive to all antibiotics. Moreover, all the strains tolerated pH (3.0, 6.5 and 8.0) and bile salt conditions (0.3, 0.6 and 1.0 % w/v). Pediococcus pentosaceus (16), Leuconostoc citreum (17), Pediococcus acidilactici (18), Enterococcus faecium (21,22), Enterococcus faecalis (24) and Limosilactobacillus fermentum (29) exhibited medium autoaggregation and affinity to chloroform. Six of the strains exhibited a ropy exopolysaccharide phenotype. Antibacterial activity against foodborne pathogens, Salmonella Typhimurium ATCC 14028, Listeria monocytogenes ATCC 19111, Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923, was found to be strain dependent, with the strains 16, 18, 21, 26, 28 and 29 presenting a higher inhibition (>4 mm) against all of them. According to Principal Component Analysis, P. pentosaceus (16), Leu. mesenteroides (26), L. casei (28), L. fermentum (29), and E. faecium (21) showed strong probiotic properties. Our findings suggest that five strains out of the 12 sampled strains are potential probiotics that could be used in the processing of traditional dairy products on an industrial scale to improve their quality.

Preliminary transcriptomic analysis of peripheral blood from German Shepherd dogs with degenerative joint disease for the identification of diagnostic biomarkers.

OBJECTIVE: Degenerative joint disease (DJD) includes a group of disorders characterised by the deterioration of the articular cartilage. In this study, we investigated the transcriptomic profile of peripheral blood in German Shepherd dogs with DJD to identify putative diagnostic biomarkers. METHODS: Differential gene expression (DGE) and gene ontology (GO) analyses of the bulk RNA-seq experiment were performed in a cohort of 12 adult dogs (five cases and seven controls, classified by clinical and radiographic analyses). RESULTS: Radiographs of cases revealed severe signs of progressive DJD. Two up-regulated (LOC106559672 and THBS4) and one down-regulated (LOC106559235) differentially expressed genes (adjusted p value < 0.05) were identified. The DGE with log2 fold change < -1.5 and > 1.5 and non-adjusted p < 0.01 were selected for GO analysis. No significant enrichment terms were observed in the selected threshold. CONCLUSION: The gene-encoding protein THBS4 is correlated with DJD severity and long noncoding RNA LOC106559235 is probably involved in the DJD process. The THBS4 gene should be considered a good biomarker for DJD in dogs. Future studies using independent cohorts will be necessary to validate the present results.

Frecuencia de infección tuberculosa latente en estudiantes de Medicina en una universidad privada de Paraguay

Introducción: la infección tuberculosa latente es un estado de respuesta inmune tipo hipersensibilidad celular retardada del organismo a la estimulación por antígenos de Mycobacterium tuberculosis sin evidencia clínica y radiológica de tuberculosis. Puede ser diagnosticada mediante la prueba de tuberculina o derivado proteico purificado de tuberculina. Objetivos: determinar la frecuencia de infección tuberculosa latente en estudiantes de Medicina y las variables asociadas a una reacción positiva en la prueba de tuberculina. Metodología: se realizó un estudio descriptivo de corte transversal, en el cual se procedió a realizar la prueba de tuberculina por el método de Mantoux utilizando 0,1 ml de derivado proteico purificado de tuberculina Tubersol, en estudiantes de la carrera de Medicina de una universidad. Resultados: participaron 290 estudiantes. La frecuencia de infección tuberculosa latente fue 19,3%. Al relacionar las variables demográficas con la reacción positiva en la prueba de tuberculina, los hombres presentaron 1,895 veces mayor probabilidad de dar positivo a la prueba de tuberculina que las mujeres. Conclusiones: la frecuencia de infección tuberculosa latente en estudiantes de la carrera de Medicina fue 19,3% y la variable que presentó asociación estadística a la prueba de tuberculina positiva fue el sexo masculino.

Introduction: Latent tuberculosis infection is a state of delayed cellular hypersensitivity immune response of the organism to stimulation by Mycobacterium tuberculosis antigens without clinical and radiological evidence of tuberculosis. It can be diagnosed by tuberculin test or tuberculin purified protein derivative. Objectives: To determine the frequency of latent tuberculosis infection in medical students and the variables associated with a positive reaction in the tuberculin test. Methodology: A descriptive cross-sectional study was carried out, in which the tuberculin test was made by the Mantoux method using 0.1 ml of purified protein derivative of Tubersol tuberculin in students of the medicine career of a university. Results: Two hundred ninety students participated. The frequency of latent tuberculosis infection was 19.3%. When relating the demographic variables to the positive reaction in the tuberculin test, men were 1,895 times more likely to test positive for the tuberculin test than women. Conclusions: The frequency of latent tuberculosis infection in medical students was 19.3% and the variable that presented a statistical association with the positive tuberculin test was male sex.

Use of near-infrared spectroscopy to estimate physical, anatomical and hydraulic properties of Eucalyptus wood.

Tree breeding programs and wood industries require simple, time- and cost-effective techniques to process large volumes of samples. In recent decades, near-infrared spectroscopy (NIRS) has been acknowledged as one of the most powerful techniques for wood analysis, making it the most used tool for high-throughput phenotyping. Previous studies have shown that a significant number of anatomical, physical, chemical and mechanical wood properties can be estimated through NIRS, both for angiosperm and gymnosperm species. However, the ability of this technique to predict functional traits related to drought resistance has been poorly explored, especially in angiosperm species. This is particularly relevant since determining xylem hydraulic properties by conventional techniques is complex and time-consuming, clearly limiting its use in studies and applications that demand large amounts of samples. In this study, we measured several wood anatomical and hydraulic traits and collected NIR spectra in branches of two Eucalyptus L'Hér species. We developed NIRS calibration models and discussed their ability to accurately predict the studied traits. The models generated allowed us to adequately calibrate the reference traits, with high R2 (≥0.75) for traits such as P12, P88, the slope of the vulnerability curves to xylem embolism or the fiber wall fraction, and with lower R2 (0.39-0.52) for P50, maximum hydraulic conductivity or frequency of ray parenchyma. We found that certain wavenumbers improve models' calibration, with those in the range of 4000-5500 cm-1 predicting the highest number of both anatomical and functional traits. We concluded that the use of NIRS allows calibrating models with potential predictive value not only for wood structural and chemical variables but also for anatomical and functional traits related to drought resistance in wood types with complex structure as eucalypts. These results are promising in light of the required knowledge about species and genotypes adaptability to global climatic change.

Coat score. A possible explanation for the zebuine selective sweep located on bovine chromosome 5: 47,670,001-48,100,000 bp.

Over 65% of the world's cattle population resides in warm areas where heat stress conditions limit the breed of European taurine cattle. Composite breeds were developed to retain the main traits of both parental breeds. The skin plays a central role in animal response to heat stress. Research on the genetic architecture of skin traits has identified genes and regions related to warm resistance skin features. The aim of this study was to determine whether the indicine proportion accounted for coat type or whether there were genes of large effect segregating in Brangus. Bulls (n = 108) were genotyped using microarrays and their coat score and hair length were evaluated. Indicine-taurine genome-wide composition was estimated and GWAS was performed. Although significant correlations between indicine proportion and traits were not observed, four windows of SNPs on BTA4 and BTA5 explained more than 2% of the trait variance. The GWAS for coat score in summer showed the main peak on BTA5:46,941,446-48,030,219 bp, accounting for 4.65% of the variance. Our results suggest that the variation in coat score and undercoat hair length in Argentinian Brangus bulls is associated with the presence of some particular gene variants, rather than with the whole indicine genetic content.

Prevalence of psychopathy in a community sample of Spanish adults: Definitions and measurements matter.

The main objective of this work is to examine the prevalence of psychopathy in the general adult population from the main currently existing theoretical perspectives of psychopathy, using for this purpose the five-factor or Big Five model as a common language that allows the comparison and integration of the personality traits considered as defining psychopathy by these different perspectives. The NEO Personality Inventory-Revised (NEO PI-R) was applied to a sample of 682 adults of the general Spanish population. The prevalence of clinical and subclinical psychopathy was calculated according to six different definitions of these two constructs based on Hare's, Lilienfeld's, triarchic, and DSM-5-hybrid models, and the simultaneous presence of a minimum number of personality traits that differed from the sample mean by one standard deviation. Prevalence rates for the different definitions were consistently low, indicating that the prevalence of clinical psychopathy in the general Spanish population is around 0.55%, and that of subclinical psychopathy is around 1.65%. There were no significant sex differences in the prevalence of psychopathy. These results question the alarmist claims that warn about the existence in society of a very high number of people with psychopathy who can cause many social, economic, physical, and psychological damage to others.

Risk Prediction and Assessment of Intervention, Re-education and Reintegration of Juvenile Offenders: Development and Psychometric Properties of the PREVI-A.

This paper proposes and analyzes the psychometric properties of the PREVI-A scale (Predicción del Riesgo y Valoración de la Intervención en la ARRMI--Risk Prediction and Intervention Assessment in the ARRMI). It describes the process of item development, the factorial structure of the scale, reliability, evidence of validity and diagnostic performance with regard to recidivism risk in juvenile offenders. The sample was made up of 212 juvenile offenders held at detention centers run by the Madrid Agency for Reeducation and Reintegration of Juvenile Offenders, a regional government body. Statistical analyses were used to corroborate the theoretical factorial structure of the PREVI-A, which consists of six risk/protection dimensions (64 items) based on the Risk-Needs-Responsivity Model, and to obtain empirical support for the reliability and validity of PREVI-A as a tool to assess the risk of recidivism by juvenile offenders in Spain.

Genome-wide scan for signatures of selection in the Brangus cattle genome.

Brangus is a composite cattle breed developed with the objective of combining the advantages of Angus and Zebuine breeds (Brahman, mainly) in tropical climates. The aim of this work was to estimate breed composition both genome-wide and locally, at the chromosome level, and to uncover genomic regions evidencing positive selection in the Argentinean Brangus population/nucleus. To do so, we analysed marker data from 478 animals, including Brangus, Angus and Brahman. Average breed composition was 35.0% ± 9.6% of Brahman, lower than expected according to the theoretical fractions deduced by the usual cross-breeding practice in this breed. Local ancestry analysis evidenced that breed composition varies between chromosomes, ranging from 19.6% for BTA26 to 56.1% for BTA5. Using approaches based on allelic frequencies and linkage disequilibrium, genomic regions with putative selection signatures were identified in several chromosomes (BTA1, BTA5, BTA6 and BTA14). These regions harbour genes involved in horn development, growth, lipid metabolism, reproduction and immune response. We argue that the overlapping of a chromosome segment originated in one of the parental breeds and over-represented in the sample with the location of a signature of selection constitutes evidence of a selection process that has occurred in the breed since its take off in the 1950s. In this regard, our results could contribute to the understanding of the genetic mechanisms involved in cross-bred cattle adaptation and productivity in tropical environments.

Production of Cellulose Nano-Fibers and Its Application in Poly-Lactic-Acid: Property Improvement by New Types of Coupling Agents.

Poly-lactic-acid is a biopolymer that can be an attractive alternative to replace petroleum-based polymers. It has advanced mechanical properties, melts easily with less energy consumption, and can be used to produce biodegradable plastics using renewable sources. However, some of the properties of poly-lactic-acid are inferior to those of traditional polymers: e.g., intensive farming is necessary for high agricultural yield, the composting needs special conditions, it is difficult to blend with other commonly used plastics, expensive, high permeability, etc. Therefore, the present work seeks to improve the structure and mechanical properties of the poly-lactic-acid incorporated by cellulose nano-fibers obtained from rice straw by a chemical acidic treatment. The fibers were incorporated into the poly-lactic-acid polymer matrix in a concentration of 1% by two-roll mill. To improve the incorporation of the fibers in the matrix, different coupling agents were used: PE-g-MA, vinyl trimethoxy silane, polyethylene-glycol with different molecular weight, and two types of experimentally synthetized α-olefin-maleic anhydride-based copolymers. The properties of the final composite could be improved, however those depend on the coupling agent to be used. The improving effect of the tested chemicals had been depended on the temperature. Based on structure analysis, both chemical and physical interactions were proposed between the cellulose nanofiber and polymer matrix. The thermogravimetric and viscosity results well represented the softener effect of the used chemical agents.

Factores psicosociales asociados a la credibilidad del testimonio en Abuso Sexual Infantil / Psychosocial factors associated with the assessment of testimony credibility in Child Sexual Abuse

Antecedentes: La credibilidad del testimonio en Abuso Sexual Infantil (ASI) es un reto para la psicología forense por falta de otras pruebas que ayuden a determinar judicialmente la ocurrencia del abuso. Existen diferentes enfoques para valorar la credibilidad del testimonio, aunque la mayoría presenta limitaciones. El propósito de esta investigación es explorar la existencia de indicadores psicosociales asociados a la credibilidad del testimonio en ASI para complementar las valoraciones periciales. Método: La muestra se compone de 99 casos de ASI evaluados como Creíbles (C) o No Creíbles (NC) con una edad que osciló entre los 4-17 años (M = 11.31, DT = 3.92) y de los que 87 (85.9%) fueron niñas. El grupo C contenía 68 casos y el NC 31. Se examinó la relación entre el dictamen pericial (C/NC) y factores psicosociales mediante tablas de contingencia y análisis de chi-cuadrado. Resultados: Encontramos diferencias significativas en variables como la presencia de desajustes sexuales y emocionales, una dinámica familiar disfuncional, el litigio entre progenitores o la denuncia contra un familiar. Conclusiones: Se identifican variables presentes de forma habitual en el grupo NC como la presencia de sintomatología de índole sexual, dinámicas disfuncionales, padres divorciados, presencia de litigio entre los progenitores o la denuncia contra el padre biológico.(AU)

Background:Credibility assessment in Child Sexual Abuse (CSA) poses a major challenge for forensic psychology. The lack of evidence sup-porting the determination of the real occurrence of the abuse requires ad-ditional approaches to assess credibility. The purpose of this research is to explore the existence of psychosocial factors associated with testimony credibility in CSA. Method:Ninety-nine CSA cases characterized as Credible (C) or Not Credible (NC) were evaluated. The age range of the group spanned 4 to 17 years (M= 11.31, SD= 3.92) with 87 (85.9%) cases corre-sponding to females. Group C incuded 68 cases and NC group the remain-ing 31. The relationship between the expert opinion (C/NC) and psycho-social factors was evaluated using contingency tables and chi-square analy-sis. Results:Significant differences in variables such as the presence of sexu-al and emotional imbalances, dysfunctional family dynamics, parent litiga-tion, or legal actions against a relative were found. Conclusions:Certain vari-ables were commonly present in the NC group, such as symptoms of a sexual nature, dysfunctional familiar dynamics, divorced parents, presence of litigation between parents, or legal actions against the biological father.(AU)

Narrow vessels cavitate first during a simulated drought in Eucalyptus camaldulensis.

Establishing drying-limits for mortality of different tree species and understanding the anatomical and physiological traits involved is crucial to predict forests' responses to climate change. The xylem of Eucalyptus camaldulensis presents a complex of solitary vessels surrounded by different imperforate tracheary elements and parenchyma that influence, in a poorly known way, its hydraulic functioning. We aimed at describing the dynamics of embolism propagation in this type of xylem, seeking any vessel-size pattern, and unraveling the threshold of xylem embolism leading to nonrecovery after drought in E. camaldulensis. We assigned potted saplings to a protracted water-stress for 70 days. We relied on colorimetric and hydraulic methods to test for links between xylem anatomy and embolism propagation in the main stem. On average, the occurrence of embolism was randomly distributed in the stem xylem, but the probability of embolized vessels was higher than predicted by chance in the narrowest vessels of individuals that experienced low to moderate water-stress. The saplings could recover from severe water-stress if their percentage loss of conductance (PLC) was <77%, but not when the PLC was ˃ 85%. We concluded that, contrary to results reported for most species, the narrowest vessels are the most vulnerable to cavitation in E. camaldulensis, suggesting a lack of tradeoff between xylem efficiency and safety (in response to drought) at the tissue level. These results challenge the well-established paradigm of the effect of vessel size on cavitation, which states that the widest conduits are the most vulnerable to both freeze-thaw and drought-induced cavitation.

Actividad citotóxica y genotóxica de ácidos grasos omega en células de cáncer de próstata PC-3 / Cytotoxic and Genotoxic Activity of Omega Fatty Acids in Prostate Cancer Cells PC-3

RESUMEN Introducción: en el mundo, el cáncer de próstata es la principal causa de muerte en hombres. Algunas evidencias sugieren que los ácidos grasos omega-3 reducen la viabilidad de las células tumorales mientras que los ácidos omega-6 promueven su proliferación; al respecto, otros estudios han mostrado resultados controvertidos. Objetivo: evaluar los efectos citotóxicos, genotóxicos y anticlonogénicos de ácidos omega-3: α-linolénico (ALA), eicosapentaenoico (EPA) y docosahexaenoico (DHA), omega-6: linoleico (LA), araquidónico (AA) y omega-9: oleico (OA) en células de cáncer de próstata (PC-3). Metodología: se evaluó el efecto sobre la viabilidad celular relativa mediante las pruebas de MTT y Azul de Tripano, el efecto genotóxico mediante intercambios de cromátidas hermanas (ICHs) y ensayo cometa, y el efecto anticlonogénico in vitro, en diferentes concentraciones (25, 50, 100 y 150 µM) de seis ácidos grasos omega en células de cáncer de próstata (PC-3). Resultados: la viabilidad relativa por MTT mostró valores ≤ IC50 con las concentraciones mayores (100 y 150 µM) para los ácidos grasos omega-3 EPA y DHA y omega-6 AA (150 µM), mientras que la viabilidad relativa, evaluada con Azul de Tripano, con estos mismos ácidos, redujeron la viabilidad a 0 %. DHA y EPA mostraron efecto genotóxico y la disminución de la clonogenicidad celular (p < 0,01). Por otro lado, LA y AA disminuyeron la viabilidad relativa observada con Azul de Tripano, sugiriendo diferentes mecanismos de acción de los ácidos grasos en la membrana celular. Conclusión: los resultados mostraron que los ácidos grasos omega-3, EPA, DHA, y omega-6, AA, disminuyen la formación de colonias, reducen la viabilidad celular y aumentan el efecto genotóxico respecto al control no tratado, en el modelo in vitro de células tumorales de próstata PC-3.

SUMMARY Introduction: Prostate cancer is the main cause of cancer related deaths in men worldwide. Previous studies have suggested that omega-3 fatty acids reduce cell viability in tumour cells, whereas omega-6 fatty acids increase clonogenicity. Nevertheless, other reports have shown controversial results. Objective: Evaluate cytotoxicity, genotoxicity and clonogenicity in a prostate cancer derived human cell line (PC-3), treated with fatty acids omega-3: α-linolenic acid (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); omega-6: linoleic acid (LA) and arachidonic acid (AA); omega-9: oleic acid (OA). Methods: The tests included (a) cytotoxicity assays by MTT and Trypan Blue; (b) genotoxicity evaluation by the sister-chromatid exchanges technique (SCE) and the DNA-comet assay; and (c) in vitro clonogenic assay of six fatty acids in prostate cancer cell (PC-3) at different concentrations (25 µM, 50 µM, 100 µM and 150 µM). Results: The cell viability by MTT data showed ≤ IC50 values for the omega-3 EPA and DHA and omega-6 AA fatty acids at the two major concentrations (100 µM and 150 µM). Moreover, the same fatty acids viability values dropped to 0 % with Trypan Blue test. EPA and DHA showed genotoxic effect and a clonogenic cell decrease (p<0,01). The latter test also revealed a viability diminishment for LA and AA, suggesting different mechanisms of action of fatty acids on cell membrane. Conclusion: The in vitro evaluation revealed that EPA, DHA and AA reduce the clonogenicity and cell viability of prostate tumour cells and cause genotoxicity in prostate tumour derived PC-3 cells.

Effect of isoespintanol isolated from Oxandra cf. xylopioides against DNA damage of human lymphocytes.

Synthetic antioxidants are used in the food and pharmaceutical industry, however, there is concern about their safety; this has prompted the search for new antioxidants that are effective, safe and act at low concentrations. The objective of this study is to evaluate the oxygen radical scavenging capacity and clastogenic effect of the Isoespintanol /2-isopropyl-3,6-dimethyl-5-methylphenol) in DNA of human lymphocyte compared with the BHA (Butylated hydroxyanisole). The oxygen radical scavenging ability was evaluated by methods ORACFL and ORACPGR, genotoxicity was determined by comet assay and data analysis was performed using ANOVA and Duncan test. The results show that the oxygen radical scavenging capacity of the BHA is higher than Isoespintanol, however according to the reactivity concept proposed by Lopez-Alarcon and Lissi, the Isoespintanol it is more reactive than BHA. Furthermore, according to some studies, BHA presented adverse effects on the health of consumers. Comet assay results revealed that at concentrations between 3 and 1620 µM the Isoespintanol don't show clastogenic effects on DNA. In conclusion, the antioxidant capacity for the BHA is higher than Isoespintanol, but considering reactivity concepts proposed by López-Alarcon and Lissi, the Isoespintanol is faster to neutralize radicals that the BHA, furthermore, according to the National Institute of Health "BHA" is a human carcinogen.

Functional relationships between wood structure and vulnerability to xylem cavitation in races of Eucalyptus globulus differing in wood density.

Wood density can be considered as a measure of the internal wood structure, and it is usually used as a proxy measure of other mechanical and functional traits. Eucalyptus is one of the most important commercial forestry genera worldwide, but the relationship between wood density and vulnerability to cavitation in this genus has been little studied. The analysis is hampered by, among other things, its anatomical complexity, so it becomes necessary to address more complex techniques and analyses to elucidate the way in which the different anatomical elements are functionally integrated. In this study, vulnerability to cavitation in two races of Eucalyptus globulus Labill. with different wood density was evaluated through Path analysis, a multivariate method that allows evaluation of descriptive models of causal relationship between variables. A model relating anatomical variables with wood properties and functional parameters was proposed and tested. We found significant differences in wood basic density and vulnerability to cavitation between races. The main exogenous variables predicting vulnerability to cavitation were vessel hydraulic diameter and fibre wall fraction. Fibre wall fraction showed a direct impact on wood basic density and the slope of vulnerability curve, and an indirect and negative effect over the pressure imposing 50% of conductivity loss (P50) through them. Hydraulic diameter showed a direct negative effect on P50, but an indirect and positive influence over this variable through wood density on one hand, and through maximum hydraulic conductivity (ks max) and slope on the other. Our results highlight the complexity of the relationship between xylem efficiency and safety in species with solitary vessels such as Eucalyptus spp., with no evident compromise at the intraspecific level.

Curso Electivo sobre Medio Ambiente y Salud / Elective course on Environment and Health

Introducción: los efectos negativos de la globalización y el neoliberalismo conducen a que la situación ambiental a nivel global, regional, territorial e incluso local se agrave cada día más, lo que hace necesaria la modificación de la conducta humana en relación con los problemas de la naturaleza, del ser humano y de la sociedad. En el caso de los médicos lo anterior adquiere mayor relevancia dada la relación entre los problemas ambientales y los problemas de salud, por esto es importante introducir la Dimensión Ambiental en los planes de estudio, vinculándola al objeto de trabajo y objetivos de la profesión, tanto desde lo curricular como de lo extracurricular. Objetivos: diseñar un programa de un curso electivo sobre Medio Ambiente y Salud como otra forma de educación ambiental desde lo extracurricular que contribuya a la formación ambiental del médico. Evaluar el nivel de conocimientos de los estudiantes sobre la Dimensión Ambiental al comienzo del curso. Métodos: se diseñó el curso electivo para estudiantes de 4to año de Medicina, con el sistema de tareas y actividades que lo conforman. Se aplicó una prueba diagnóstica inicial a dichos estudiantes. Resultados: la prueba diagnóstica fue desaprobada por el 60 por ciento de los estudiantes obteniéndose estos menos de 21 puntos de un total de 30. El 100 por ciento de los estudiantes aprobaron el curso, alcanzando la máxima calificación el 80 por ciento de ellos. Conclusiones: el curso, desde lo extracurricular puede contribuir al desarrollo de la Educación Ambiental en estudiantes de Medicina(AU)

Introduction: The negative effects of neoliberalism and globalization lead to the environment's global, regional, territorial, and even local situation worsening day by day, which makes necessary the modification of the human conduct regarding the problems of nature, the human being and the society. In the case of physicians, the latter becomes more relevant given the relation between the environmental and health problems; therefore, it is important to present the environmental dimension into the curricula, relating it with the object of work and objectives of the profession, from both the curricular and the extra-curricular approaches. Objective: Design an elective course program about Environment and Health as a way for environmental education, from the extracurricular approach, which contributes to the physician's environmental training. Assess, at the beginning of the course, the students' level of knowledge about the environmental dimension. Methods: The elective course with the system of tasks and activities was designed for four year medical students. These students were applied an initial diagnostic test. Results: 60 percent of the students did not pass the diagnostic test; they obtained less than 21/30 points. 100 percent of the students passed the course; 80 percent of them obtained the highest qualification. Conclusions: The course, from the extra-curricular approach, may contribute to the development of environmental education on medical students(AU)

Synthesis and cytotoxic activity of tri-acyl ester derivatives of uridine in breast cancer cells / Síntesis y actividad citotóxica de derivados triesterificados de la uridina en células de cáncer de mama

Aims: Synthesize tri-acyl ester derivatives of uridine, and evaluate its cytotoxicity against breast cancer cells line. Methods: The tri-esterified uridine derivatives were obtained through Steglich esterification reaction by fatty and aromatic acids, and with acetic anhydride. An acetonide derivative from uridine was prepared with acid catalysis. Compounds were characterized by NMR spectroscopy (1H NMR and 13C NMR), and mass spectrometry. Derivatives were assessed in chinese hamster ovary (CHO-K1) and human breast cancer (MCF-7) cell lines. Results: Five tri-acyl ester derivatives of uridine were obtained one acetic acid, three fatty acids (myristic acid, stearic acid and oleic acid) with an aromatic acid. The uridine per-acetylated and uridine acetonide were obtained in high yields, however, the tri-acyl ester derivatives of uridine with fatty and aromatic acids were obtained in moderate and low yields, respectively. The acetonide and compounds 2 and 3 exhibited a cell viability inhibition significant on both cell lines to the higher concentration. Conclusions: Esterification method with coupling agents allowed obtained tri-acyl ester uridine derivatives with aliphatic and aromatic acids. However, significant cytotoxic activity (p<0.05) for uridine and its derivatives was not observed

Objetivos: Sintetizar derivados triesterificados de la uridina y evaluar su citotóxicidad sobre una línea celular de cáncer de mama. Métodos: Se prepararon derivados triesterificados de la uridina mediante la esterificación de Steglich para los ácidos grasos y aromáticos, y con anhídrido acético. Además se preparó el derivado acetonido mediante catálisis ácida. Los compuestos se caracterizaron por espectroscopia de RMN (RMN 1H y RMN 13C), y espectrometría de masas. Los derivados se evaluaron sobre líneas celulares de tumor de ovario de hámster chino (CHO) y de cáncer de mamá (MCF-7). Resultados: Se obtuvieron cinco derivados triesterificados de la uridina, uno con ácido acético, tres con ácidos grasos (ácido mirístico, ácido esteárico y ácido oleico) y uno con ácido aromático. Los derivados de uridina per-acetilada y acetonido se obtuvieron con rendimientos altos, sin embargo los derivados con ácidos grasos y aromático, se obtuvieron con rendimientos moderados y bajo, respectivamente. El acetonido y los compuestos 2 y 3, exhibieron inhibición significativa de la viabilidad celular sobre ambas líneas a la concentración más alta evaluada. Conclusiones: El método de esterificación con agentes de acoplamiento utilizado, permitió obtener derivados triesterificados de la uridina con ácidos grasos y aromáticos. No se observó actividad citotóxica significativa (p<0,05) para la uridina y sus derivados

Curso Electivo sobre Medio Ambiente y Salud / Elective course on Environment and Health

Introducción: los efectos negativos de la globalización y el neoliberalismo conducen a que la situación ambiental a nivel global, regional, territorial e incluso local se agrave cada día más, lo que hace necesaria la modificación de la conducta humana en relación con los problemas de la naturaleza, del ser humano y de la sociedad. En el caso de los médicos lo anterior adquiere mayor relevancia dada la relación entre los problemas ambientales y los problemas de salud, por esto es importante introducir la Dimensión Ambiental en los planes de estudio, vinculándola al objeto de trabajo y objetivos de la profesión, tanto desde lo curricular como de lo extracurricular.Objetivos: diseñar un programa de un curso electivo sobre Medio Ambiente y Salud como otra forma de educación ambiental desde lo extracurricular que contribuya a la formación ambiental del médico. Evaluar el nivel de conocimientos de los estudiantes sobre la Dimensión Ambiental al comienzo del curso.Métodos: se diseñó el curso electivo para estudiantes de 4to año de Medicina, con el sistema de tareas y actividades que lo conforman. Se aplicó una prueba diagnóstica inicial a dichos estudiantes.Resultados: la prueba diagnóstica fue desaprobada por el 60 por ciento de los estudiantes obteniéndose estos menos de 21 puntos de un total de 30. El 100 por ciento de los estudiantes aprobaron el curso, alcanzando la máxima calificación el 80 por ciento de ellos.Conclusiones: el curso, desde lo extracurricular puede contribuir al desarrollo de la Educación Ambiental en estudiantes de Medicina(AU)

Introduction: The negative effects of neoliberalism and globalization lead to the environment's global, regional, territorial, and even local situation worsening day by day, which makes necessary the modification of the human conduct regarding the problems of nature, the human being and the society. In the case of physicians, the latter becomes more relevant given the relation between the environmental and health problems; therefore, it is important to present the environmental dimension into the curricula, relating it with the object of work and objectives of the profession, from both the curricular and the extra-curricular approaches.Objective: Design an elective course program about Environment and Health as a way for environmental education, from the extracurricular approach, which contributes to the physician's environmental training. Assess, at the beginning of the course, the students' level of knowledge about the environmental dimension.Methods: The elective course with the system of tasks and activities was designed for four year medical students. These students were applied an initial diagnostic test.Results: 60 percent of the students did not pass the diagnostic test; they obtained less than 21/30 points. 100 percent of the students passed the course; 80 percent of them obtained the highest qualification.Conclusions: The course, from the extra-curricular approach, may contribute to the development of environmental education on medical students(AU)

Curso Electivo sobre Medio Ambiente y Salud / Elective course on Environment and Health

Introducción: los efectos negativos de la globalización y el neoliberalismo conducen a que la situación ambiental a nivel global, regional, territorial e incluso local se agrave cada día más, lo que hace necesaria la modificación de la conducta humana en relación con los problemas de la naturaleza, del ser humano y de la sociedad. En el caso de los médicos lo anterior adquiere mayor relevancia dada la relación entre los problemas ambientales y los problemas de salud, por esto es importante introducir la Dimensión Ambiental en los planes de estudio, vinculándola al objeto de trabajo y objetivos de la profesión, tanto desde lo curricular como de lo extracurricular. Objetivos: diseñar un programa de un curso electivo sobre Medio Ambiente y Salud como otra forma de educación ambiental desde lo extracurricular que contribuya a la formación ambiental del médico. Evaluar el nivel de conocimientos de los estudiantes sobre la Dimensión Ambiental al comienzo del curso. Métodos: se diseñó el curso electivo para estudiantes de 4to año de Medicina, con el sistema de tareas y actividades que lo conforman. Se aplicó una prueba diagnóstica inicial a dichos estudiantes. Resultados: la prueba diagnóstica fue desaprobada por el 60 por ciento de los estudiantes obteniéndose estos menos de 21 puntos de un total de 30. El 100 por ciento de los estudiantes aprobaron el curso, alcanzando la máxima calificación el 80 por ciento de ellos. Conclusiones: el curso, desde lo extracurricular puede contribuir al desarrollo de la Educación Ambiental en estudiantes de Medicina(AU)

Introduction: The negative effects of neoliberalism and globalization lead to the environment's global, regional, territorial, and even local situation worsening day by day, which makes necessary the modification of the human conduct regarding the problems of nature, the human being and the society. In the case of physicians, the latter becomes more relevant given the relation between the environmental and health problems; therefore, it is important to present the environmental dimension into the curricula, relating it with the object of work and objectives of the profession, from both the curricular and the extra-curricular approaches. Objective: Design an elective course program about Environment and Health as a way for environmental education, from the extracurricular approach, which contributes to the physician's environmental training. Assess, at the beginning of the course, the students' level of knowledge about the environmental dimension. Methods: The elective course with the system of tasks and activities was designed for four year medical students. These students were applied an initial diagnostic test. Results: 60 percent of the students did not pass the diagnostic test; they obtained less than 21/30 points. 100 percent of the students passed the course; 80 percent of them obtained the highest qualification. Conclusions: The course, from the extra-curricular approach, may contribute to the development of environmental education on medical students(AU)