106 research outputs found

    Acumulación estacional de una deshidrina de 47-kDa en hojas y cambios en su actividad crioprotectora en Nothofagus dombeyi (Mirb.) Blume

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    Nothofagus dombeyi (Mirb.) Blume is an evergreen tree, pioneer in habitats subject to unfavorable environmental conditionsas nighttime freezing temperatures and low water content. It inhabits zones characterized by cold Winter with freezingtemperature and Spring frosts reaching to -5ºC. Furthermore, it has the capacity to maintain a functional photosyntheticapparatus at low temperatures. We postulated that N. dombeyi is capable to accumulate dehydrins in leaves in response tocold. Seasonal variation in dehydrins, soluble total proteins, and cryoprotective activity in vitro of protein extracts of N.dombeyi leaves were analyzed during the years 2004 and 2005. A dehydrin-like protein of 47-kDa was immunologicallyidentified; this protein was present only in Winter and Spring. The highest accumulation of this protein and the maximalin vitro cryoprotective activity was found during Spring. The leaf total protein extract of this season preserved the 100%of lactate dehydrogenase (LDH) enzyme activity after 5 freeze/thaw cycles in liquid nitrogen adding 10 ?g/ml of totalproteins extract. The soluble protein concentration increased from 1.8 mg/g in Summer to 4.8 mg/g in Fall on base offresh weight, and declined through Winter and Spring. The 47-kDa dehydrin may be related to cold hardiness of leaftissue in overwintering N. dombeyi. We conclude that cell dehydration caused by freezing is the main factor involved inthe triggering of 47-kDa dehydrin accumulation in leaves of N. dombeyi. The accumulation of reactive oxygen species(ROS) by oxidative stress product of high irradiance and frosts during Spring, and their role in the triggering of the 47-kDadehydrin accumulation in leaves of N. dombeyi is discussed.Nothofagus dombeyi (Mirb.) Blume es un árbol siempreverde, pionero en sitios con condiciones ambientales desfavorablescomo baja temperatura nocturna y baja disponibilidad hídrica. Habita en zonas caracterizadas por inviernos fríos contemperaturas congelantes y heladas de primavera que pueden llegar a los -5ºC. Además tiene la capacidad de mantenersu aparato fotosintético funcional en condiciones de baja temperatura. Postulamos que N. dombeyi es capaz de acumulardeshidrinas en sus hojas en respuesta a baja temperatura. Se analizó la variación estacional de deshidrinas, proteínas solublestotales y la actividad crioprotectora in vitro de extractos proteicos de hojas de N. dombeyi durante los años 2004 y 2005. Unaproteína con características de deshidrina de 47 kDa de peso molecular fue identificada inmunológicamente en hojas, la queestuvo presente sólo en invierno y primavera. La mayor acumulación de esta proteína en las hoja y la máxima crioprotecciónin vitro fue encontrada durante la estación de primavera. El extracto total de proteínas de esta estación conservó el 100% dela actividad de la enzima lactato deshidrogenasa (LDH) después de 5 ciclos de congelamiento/descongelamiento en nitrógenolíquido agregando 10 ?g/ml de extracto total de proteínas. La concentración de proteínas solubles totales aumentó de 1,8 mgpor gramo de peso fresco en verano a 4,8 mg en otoño, y disminuyó durante el invierno y la primavera. La deshidrina de 47kDa podría estar relacionada al endurecimiento por frío del tejido foliar en individuos de N. dombeyi durante el invierno,aumentando su resistencia al congelamiento. Concluimos que la deshidratación celular producida por congelamiento sería elprincipal factor en estimular la acumulación de esta deshidrina de 47kDa en hojas de N. dombeyi. La acumulación de especiesreactivas de oxígeno (ROS) por estrés oxidativo producto de la alta irradiancia y heladas durante la primavera y su papel en elgatillamiento de la acumulación de esta deshidrina de 47 kDa en las hojas es discutida

    Seasonal induction of cluster roots in Embothrium coccineum J.R. Forst. & G. Forst. in the field: factors that regulate their development

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    Embothrium coccineum J.R. Forst. & G. Forst. (Proteaceae) is a tree that grows successfully in nutrient poor soils of southern Chile at full sunlight. Under these conditions it develops cluster roots (CR). However, the induction of CR on this species has not been studied completely. The aim of this work was to study the effect of seasonality, soil and weeds in the development of CR in E. coccineum . The present study was performed in Los Lagos Region (41º72’ S lat), Chile. Plants of E. coccineum were grown in sandy soils in presence or absence of weeds, using two concentrations of organic matter. The number of CR per plant, CR mass and P concentration in leaves was measured during the four seasons in E. coccineum plants. The CR development in the soil with high organic matter concentration and without weeds was observed in autumn, spring and summer, and in the soil with low organic matter concentration was observed in autumn, winter and spring. Not found related of this result with the foliar P concentration in E. coccineum. The results suggest a strong seasonal and weeds effect on CR development in E. coccineum under field conditions

    Inhibition of ATPase from chloroplasts by a hydroxamic acid from Gramineae.

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    Abstract-DIMBOA (2,4-dihydroxy-7-methoxy-l,4-benzoxazin-3-one), a hydroxamic acid from the Gramineae involved in the resistance of cereals to aphids, inhibits energy transfer reactions. In this paper the effect of DIMBOA on the ATPase activity of chloroplast coupling factor 1 (CF,) was studied. A rapid inactivation of the enzyme was observed which increased with the concentration of DIMBOA. This inactivation was reversed by dilution and by filtration of the inhibitor. The inactivation was partially prevented by pre-treatment of the enzyme with iodoacetamide. A slower simultaneous inactivation was observed which followed pseudo-first order kinetics. It is suggested that part of the rapid inhibition of CF, ATPase caused by DIMBOA is due to its reaction with sulthydryl groups on the enzyme. These reactions of DIMBOA may explain some of the inhibitory properties of DIMBOA on a wide range of organisms

    Differential Expression of Inflammation-Related Genes in Down Syndrome Patients with or without Periodontal Disease

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    Aim. Aware that Down Syndrome patients present among their clinical characteristics impaired immunity, the aim of this study is to identify the statistically significant differences in inflammation-related gene expression by comparing Down Syndrome patients with Periodontal Disease (DS+PD+) with Down Syndrome patients without Periodontal Disease (DS+PD-), and their relationship with periodontitis as a chronic oral inflammatory clinical feature. Materials and Methods. Case study and controls on eleven Down Syndrome patients (DS+PD+ vs. DS+PD-). RNA was extracted from peripheral blood using a Qiagen PAXgene Blood miRNA Kit when performing an oral examination. A search for candidate genes (92 selected) was undertaken on the total genes obtained using a Scientific GeneChip® Scanner 3000 (Thermo Fisher Scientific) and Clariom S solutions for human, mouse, and rat chips, with more than 20,000 genes annotated for measuring expression levels. Results. Of the 92 inflammation-related genes taken initially, four genes showed a differential expression across both groups with a p value of <0.05 from the data obtained using RNA processing of the patient sample. Said genes were TNFSF13B (p = 0:0448), ITGB2 (p = 0:0033), ANXA3 (p = 0:0479), and ANXA5 (p = 0:016). Conclusions. There are differences in inflammation-related gene expression in Down Syndrome patients when comparing patients who present a state of chronic oral inflammation with patients with negative rates of periodontal disease

    Bycatch of franciscana dolphins Pontoporia blainvillei and the dynamic of artisanal fisheries in the species' southernmost area of distribution

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    Na Argentina, a toninha é um dos cetáceos mais vulneráveis devido às capturas por rede de pesca artesanal. O presente estudo teve como objetivo estimar as capturas acidentais no sul da província de Buenos Aires, através de entrevistas aos capitães de barcos de pesca artesanal, entre os anos 2006-2009. As capturas foram reportadas para redes de emalhe e de camarão; com as mais altas frequências entre outubro e fevereiro, a 5 km da costa e 10-20 m de profundidade. A mortalidade acidental média anual estimada foi de 107 golfinhos (IC 95% = 87-129), 92 em redes de emalhe (IC 95% = 73-112) e 15 em redes de camarão (IC 95% = 8-25), com uma captura de 0,029 golfinhos/km de rede de emalhe (IC 95% = 0,023-0,036) e 0,024/rede de camarão (IC 95% = 0,012-0,035). As flutuações anuais responderam principalmente às diferenças nos dias de pesca. Considerando o último levantamento estimativo feito para o norte costeiro da província, estima-se uma mortalidade entre 360-539 golfinhos/ano em toda a província de Buenos Aires. Esses valores correspondem de 2,5-3,7% da abundância populacional da Argentina; o que traria como consequência um declínio populacional da espécie, tornando-se fundamental encontrar alternativas de pesca para a área.In Argentina, the franciscana dolphin is one of the most vulnerable cetaceans regularly entangled in coastal artisanal fishery nets. The aim of this paper is to estimate the species' incidental mortality on the Southern coast of Buenos Aires province through interviews with the captains of artisanal fishing vessels, in the period 2006-2009. Franciscana bycatch was reported for gillnets and shrimper gear all year round but it occurred more frequently between October and February, at 5 km offshore and 10-20 m depth. The estimated mean annual incidental mortality was 107 dolphins (CI 95% = 87-129), 92 caught in gillnets (CI 95% = 73-112) and 15 in shrimpers' gear (CI 95% = 8-25) with a capture per unit effort of 0.029 dolphins per km of gillnet (CI 95% = 0.023-0.036) and 0.022 per shrimpe r's net (CI 95% = 0.012-0.035). Annual fluctuations were due to differences in the number of gillnetting fishing days. If mortality estimates for the Northern coast are also taken into account, values attain a maximum of 360-539 dolphins bycaught in the entire Buenos Aires province, representing 2.5-3.7% of the species' abundance in Argentina. This will inevitably lead to the decline of franciscana dolphin populations in the near future unless alternative fishing grounds are identified and alternative gearadopted

    Multi-ancestry genome-wide association study of asthma exacerbations

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    Altres ajuts: European Regional Development Fund "ERDF A way of making Europe"; Allergopharma-EAACI award 2021; SysPharmPedia grant from the ERACoSysMed 1st Joint Transnational Call from the European Union under the Horizon 2020; Sandler Family Foundation; American Asthma Foundation; RWJF Amos Medical Faculty Development Program; National Heart, Lung, and Blood Institute of the National Institutes of Health (R01HL117004, R01HL128439, R01HL135156, X01HL134589, R01HL141992, R01HL141845); National Institute of Health and Environmental Health Sciences (R01ES015794, R21ES24844); National Institute on Minority Health and Health Disparities (NIMHD) (P60MD006902, R01MD010443, R56MD013312); National Institute of General Medical Sciences (NIGMS) (RL5GM118984); Tobacco-Related Disease Research Program (24RT-0025, 27IR-0030); National Human Genome Research Institute (NHGRI) (U01HG009080); GlaxoSmithKline and Utrecht Institute for Pharmaceutical Sciences; Slovenian Research Agency (P3-0067); SysPharmPediA grant, co-financed by the Ministry of Education, Science and Sport Slovenia (MIZS) (C3330-16-500106); NHS Research Scotland; Wellcome Trust Biomedical Resource (099177/Z/12/Z); Genotyping National Centre (CeGEN) CeGen-PRB3-ISCIII (AC15/00015); UK Medical Research Council and Wellcome (102215/2/13/2); University of Bristol; Swedish Heart-Lung Foundation, Swedish Research Council; Region Stockholm (ALF project and database maintenance); NHS Chair of Pharmacogenetics via the UK Department of Health; Innovative Medicines Initiative (IMI) (115010); European Federation of Pharmaceutical Industries and Associations (EFPIA); Spanish National Cancer Research Centre; Fundación Canaria Instituto de Investigación Sanitaria de Canarias (PIFIISC19/17); Erasmus Medical Center; Erasmus University Rotterdam; Netherlands Organization for the Health Research and Development (ZonMw); the Research Institute for Diseases in the Elderly (RIDE); Ministry of Education, Culture and Science; Ministry for Health, Welfare and Sports; European Commission (DG XII); Municipality of Rotterdam; German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, BMBF); U.S. National Institutes of Health (HL07966); European Social Fund "ESF Investing in your future"; Ministerio de Ciencia, Innovación y Universidades; Universidad de La Laguna (ULL); European Academy of Allergy and Clinical Immunology (EAACI); European Respiratory Society (ERS) (LTRF202101-00861); Ministry of Education, Science and Sport of the Republic of Slovenia (C3330-19-252012); Singapore Ministry of Education Academic Research Fund; Singapore Immunology Network (SIgN); National Medical Research Council (NMRC Singapore); Biomedical Research Council (BMRC Singapore); Agency for Science Technology and Research (A*STAR Singapore, N-154-000-038-001, R-154-000-191-112, R-154-000-404-112, R-154-000-553-112, R-154-000-565-112, R-154-000-630-112, R-154-000-A08-592, R-154-000-A27-597, R-154-000-A91-592, R-154-000-A95-592, R-154-000-B99-114, BMRC/01/1/21/18/077, BMRC/04/1/21/19/315, SIgN-06-006, SIgN-08-020, NMRC/1150/2008, H17/01/a0/008); Sime Darby Technology Centre; First Resources Ltd; Genting Plantation; Olam International; U.S. National Institutes of Health (HL138098).Background: Asthma exacerbations are a serious public health concern due to high healthcare resource utilization, work/school productivity loss, impact on quality of life, and risk of mortality. The genetic basis of asthma exacerbations has been studied in several populations, but no prior study has performed a multi-ancestry meta-analysis of genome-wide association studies (meta-GWAS) for this trait. We aimed to identify common genetic loci associated with asthma exacerbations across diverse populations and to assess their functional role in regulating DNA methylation and gene expression. Methods: A meta-GWAS of asthma exacerbations in 4989 Europeans, 2181 Hispanics/Latinos, 1250 Singaporean Chinese, and 972 African Americans analyzed 9.6 million genetic variants. Suggestively associated variants (p ≤ 5 × 10) were assessed for replication in 36,477 European and 1078 non-European asthma patients. Functional effects on DNA methylation were assessed in 595 Hispanic/Latino and African American asthma patients and in publicly available databases. The effect on gene expression was evaluated in silico. Results: One hundred and twenty-six independent variants were suggestively associated with asthma exacerbations in the discovery phase. Two variants independently replicated: rs12091010 located at vascular cell adhesion molecule-1/exostosin like glycosyltransferase-2 (VCAM1/EXTL2) (discovery: odds ratio (OR) = 0.82, p = 9.05 × 10 and replication: OR = 0.89, p = 5.35 × 10) and rs943126 from pantothenate kinase 1 (PANK1) (discovery: OR = 0.85, p = 3.10 × 10 and replication: OR = 0.89, p = 1.30 × 10). Both variants regulate gene expression of genes where they locate and DNA methylation levels of nearby genes in whole blood. Conclusions: This multi-ancestry study revealed novel suggestive regulatory loci for asthma exacerbations located in genomic regions participating in inflammation and host defense

    Epigenome-Wide Association Studies of the Fractional Exhaled Nitric Oxide and Bronchodilator Drug Response in Moderate-to-Severe Pediatric Asthma

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    Asthma is the most prevalent pediatric chronic disease. Bronchodilator drug response (BDR) and fractional exhaled nitric oxide (FeNO) are clinical biomarkers of asthma. Although DNA methylation (DNAm) contributes to asthma pathogenesis, the influence of DNAm on BDR and FeNO is scarcely investigated. This study aims to identify DNAm markers in whole blood associated either with BDR or FeNO in pediatric asthma. We analyzed 121 samples from children with moderate-to-severe asthma. The association of genome-wide DNAm with BDR and FeNO has been assessed using regression models, adjusting for age, sex, ancestry, and tissue heterogeneity. Cross-tissue validation was assessed in 50 nasal samples. Differentially methylated regions (DMRs) and enrichment in traits and biological pathways were assessed. A false discovery rate (FDR) < 0.1 and a genome-wide significance threshold of p < 9 × 10−8 were used to control for false-positive results. The CpG cg12835256 (PLA2G12A) was genome-wide associated with FeNO in blood samples (coefficient= −0.015, p = 2.53 × 10−9) and nominally associated in nasal samples (coefficient = −0.015, p = 0.045). Additionally, three CpGs were suggestively associated with BDR (FDR < 0.1). We identified 12 and four DMRs associated with FeNO and BDR (FDR < 0.05), respectively. An enrichment in allergic and inflammatory processes, smoking, and aging was observed. We reported novel associations of DNAm markers associated with BDR and FeNO enriched in asthma-related processes

    Comparación de dos métodos para generar curvas presión-volumen en especies del género Quercus

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    Effects of indole alkaloids from gramineae on aphids

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    The indole bases N∞-methyltryptamine, 5-methoxy-N, N-dimethyltryptamine, 3-N,N-dimethylaminomethylindole (gramine) and 5-methoxytryptamine decreased survival of nymphs of Rhopalosiphum maidis with LD50 of 3.8, 3.5, 2.9 and 2.3 mM, respectively, after 48 hr of feeding with a synthetic diet. Gramine also decreased survival of Schizaphis graminum with an LD50 of 0.7 mM after 48 hr of feeding. The four compounds tested showed feeding deterrent activity on the aphids at concentrations as low as 0.5 mM. In addition, gramine showed toxic effects on S. graminum. Since the deleterious effects of gramine and related compounds in synthetic diets are observed at concentrations similar to those found in plants, it is possible that these molecules may have a role in protecting the plant against aphids. © 1984
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