692 research outputs found

    Maize (Zea mays L) cultivars nutrients concentration in leaves and stalks

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    There is pressure for crop residue removal for use as biofuel, animal feed, animal bedding and many other func¬tions which may increase nutrient export. However, there is little information about nutritional composition of maize stover considering the wide variability of cultivars used. The aim of this study was to evaluate the influence of maize cultivar on macronutrient (P, K, Ca, and Mg), micronutrient (Fe, Mn, Zn, and Cu) and Na concentration in leaves and stalks. We selected five pairs of cultivars, ranging from creole to high potential hybrid (creole, commer¬cial variety, single, double and triple cross hybrid). The cultivars were cropped under field conditions in high fertile Rhodic Ferralsol Eutric during two growing seasons. The first was characterized by severe drought (2005/2006) while the second with an abundant water supply (2006/2007). The leaf and stalk concentrations of P, K, Ca, Mg, Fe, Mn, Na, Zn, Cu, and C/P ratio were quantified at maturation stage. The results indicated that the P concen¬tration in leaves and stalks was inversely related to the technological level when simple hybrid was compared to creole cultivars. Similar behavior was observed for K in the leaf and stalk tissues. For Ca, Mg, Fe, Mn, Zn, Cu, and Na, it was not possible to establish the influence of maize selection. The C/P ratio of leaves and stalks underwent influence of the technological level with high values for simple hybrids. Maize selection seems to decrease P and K concentration for two major residue fractions, leaves and stalks

    Purification, characterization and application of laccase from Trametes versicolor for colour and phenolic removal of olive mill wastewater in the presence of 1- hydroxybenzotriazole

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    Laccase forms (L1 and L2) from Trametes versicolor CCT 4521 showed a molecular mass of 66 kDa and optimum temperature around 40oC. The optimum pH (4.0 and 5.0) and Km (28.6 and 5 ìM) values usingsyringaldazine as substrate were found for L1 and L2, respectively. The enzymes were able to oxidize several compounds and were strongly inhibited by sodium azide, L-cysteine and dithiothreitol. The 75%of the N-terminal sequences were identical in both forms and similarities around 40 - 60% of laccases from wood-degrading fungi were observed. The use of 1-hydroxybenzotriazole as a mediator increased the compounds oxidized by laccases in olive mill wastewater

    Carbon stable isotope record in the coral species Siderastrea stellata: A link to the Suess Effect in the tropical South Atlantic Ocean

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    This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Coral skeletons are natural archives whose geochemical signatures provide insights into the tropical ocean history beyond the instrumental record. Carbon stable isotopes from coral skeletons (δ13Ccoral) have been used as a proxy for multiple variables on a seasonal basis. Long-term changes in coral δ13C could be related to the changing isotopic composition of the dissolved inorganic carbon (δ13CDIC). δ13CDIC in turn reflects changes in the δ13C of atmospheric CO2, which in the modern Earth system is governed primarily by anthropogenic injection of CO2 into the atmosphere – a process known as the Suess Effect. Here we report three δ13C coral-based records of Siderastrea stellata from the tropical South Atlantic. U-series dating for the colonies 12SFB-1, 13SS-1 and 13SS-2 suggests these corals lived 13, 57 and 65 years, respectively. Short-term δ13C variations in their skeletal aragonite are dominated by interannual variation. All three δ13C records additionally exhibit an overall decreasing trend, with a depletion of about −0.0243 ± 0.0057‰·yr−1 (12SFB-1), −0.0208 ± 0.0007‰·yr−1 (13SS-1) and −0.0214 ± 0.0013‰·yr−1 (13SS-2). These rates of the coral records from Rocas Atoll are similar to the reported trend for the δ13C of atmospheric CO2 over the years 1960–1990 (−0.023 to −0.029‰·yr−1), and to the decreasing rates of global δ13CDIC. Our findings suggest that multiple δ13C coral-based records are required for confidently identifying local changes in the δ13CDIC of the ocean. This information, in turn, can be used to infer changes in the δ13C of the atmospheric CO2 composition and provide valuable information about recent changes on the carbon biogeochemical cycle during the Anthropocene epoch.NSP acknowledges the National Counsel of Technological and Scientific Development (CNPq) for a Post-Doctoral Scholarship Proc. no 150405/2015-4. We thank the chief of the Biological Reserve of Rocas Atoll, Maurizélia de Brito Silva and the field team Tiago Albuquerque, Miguel Miranda, Mirella B. Costa and Eduardo Macêdo, for the great assistance in this study. We thank Gilsa Santana, Vilma Sobral (NEG-LABISE, Brazil) and Bo Petersen (University of Copenhagen) for assisting in stable isotope measurements. We are thankful for the critical and constructive comments of the anonymous reviewers. The 2013 field work was partially supported by National Geographic Waitt Foundation grant W21-12 to K.H.K. and R.K.P.K. U-Th dating was supported by grants from Ministry of Science and Technology (MOST) (105-2119-M-002-001, 106-2628-M-002-013 to C.-C.S.) and the National Taiwan University (105R7625 to C.-C.S.). This manuscript is the scientific contribution no 288 of the NEG-LABISE, UFPE, a contribution of the Reef Ecosystems Working Group of the INCT Ambientes Marinhos Tropicais (InctAmbTropic – CNPq #565.054/2010-4) and represents contribution 5470 of the University of Maryland Center for Environmental Science

    Caracterización epidemiológica del dengue en la Unidad de Terapia Intensiva Adultos. Hospital Central “Dr. Emilio Cubas” del Instituto de Previsión Social, Paraguay

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    El dengue es una infección viral sistémica, autolimitada y transmitida por mosquitos. En los últimos 50 años, a nivel mundial, aumentó la incidencia 30 veces, con circulación de los cuatro serotipos virales. Paraguay presenta condiciones socio-ambientales favorables para su transmisión, lo cual puede afectar la disponibilidad de recursos para el manejo de los casos graves. El objetivo del estudio fue determinar la frecuencia de dengue en la Unidad de Terapia Intensiva Adultos (UTIA) del Hospital Central del Instituto de Previsión Social, de junio del 2.011 a junio del 2.013. El estudio es observacional descriptivo, de corte transversal. De 1.991 pacientes admitidos en UTIA, en 103 (5,2%) se confirmó dengue tanto por clínica como por hallazgos laboratoriales. El 72,7% era del sexo femenino, la mediana de edad fue de 47 años, y 53,4% residía en Asunción. La mediana del tiempo hasta la primera consulta fue 2 días. El 87,4% presentó fiebre; el 65,05% sangrado y de estos el 52,2% requirió transfusión de hemoderivados. Las medianas de las puntuaciones APACHE II y SOFA fueron de 10 y 5, respectivamente. La mitad presentaba al menos una condición clínica coexistente. En promedio, la solicitud de la prueba NS1 fue a los 3±1 días y la IgG/IgM a 6±2 días. El 64,1% fue grave, complicándose el 73,8%. La internación en cuidados intensivos fue en promedio 4 días. A pesar de la relativa baja frecuencia de esta enfermedad en la unidad, su relevancia radica en la gran morbimortalidad observada en estos pacientes

    Modulation of Src Activity by Low Molecular Weight Protein Tyrosine Phosphatase During Osteoblast Differentiation

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Background: Src kinase plays a critical role in bone metabolism, particularly in osteoclasts. However, the ability of Src kinase to modulate the activity of other bone cells is less well understood. In this work, we examined the expression and activity of Src and low molecular weight protein tyrosine phosphatase (LMWPTP) during osteoblast differentiation and assessed the modulation of Src kinase by LMWPTP. Methods: Differentiation of MC3T3-E1 pre-osteoblasts was induced by incubation with ascorbic acid and beta-glycerophosphate for up to 28 days. Src phosphorylation and LMWPTP expression were analyzed by immunoblotting. Src dephosphorylation in vitro was assessed by incubating immunoprecipitated Src with LMWPTP followed by assay of the residual Src activity using Sam68 as substrate. The importance of LMWPTP in Src dephosphorylation was confirmed by silencing pre-osteoblasts with siRNA-LMWPTP and then assessing Src phosphorylation. Results: Pre-osteoblast differentiation was accompanied by a decrease in phosphorylation of the activator site of Src and an increase in phosphorylation of the inhibitory site. The expression of total Src was unaltered, indicating that post-translational modifications play a pivotal role in Src function. LMWPTP expression was higher in periods when the activator site of Src was dephosphorylated. LMWPTP dephosphorylated pY(527)-Src and pY(416)-Src in vitro, with greater specificity for pY(527) Src. Activation of LMWPTP produced strong activation of Src mediated by fast dephosphorylation of pY(527)-Src, followed by slower deactivation of this kinase via dephosphorylation of pY(416) Src. Conclusion: These results provide new insight into the mechanisms governing the dynamics of Src activity during osteoblast differentiation. A fuller understanding of these mechanisms will improve our knowledge of bone metabolism and of the regulation of Src in other types of cells. Copyright (c) 2008 S. Karger AG, Basel2241795497506Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [04/14906-2

    Riboflavin:A multifunctional vitamin.

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    Riboflavin, a component of the B-2 vitaminic complex, plays important roles in biochemistry, especially in redox reactions, due to the ability to participate in both one- and two-electron transfers as well as acting as a photosensitizer. Accordingly, low intakes of this vitamin have been associated with different diseases, including cancer and cardiovascular diseases. Riboflavin is thought to contribute to oxidative stress through its capacity to produce superoxide but, interestingly, it can also promote the reduction of hydroperoxides. This peculiar and multifunctional behavior allows riboflavin to take part in various biochemical pathways as a nucleophile and an electrophile, turning it into a versatile and important biological compound

    Purification, characterization and application of laccase from Trametes versicolor for colour and phenolic removal of olive mill wastewater in the presence of 1-hydroxybenzotriazole

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    Laccase forms ( L1 and L2) from Trametes versicolor CCT 4521 showed a molecular mass of 66 kDa and optimum temperature around 40 degrees C. The optimum pH ( 4.0 and 5.0) and K-m ( 28.6 and 5 mu M) values using syringaldazine as substrate were found for L1 and L2, respectively. The enzymes were able to oxidize several compounds and were strongly inhibited by sodium azide, L-cysteine and dithiothreitol. The 75% of the N-terminal sequences were identical in both forms and similarities around 40-60% of laccases from wood-degrading fungi were observed. The use of 1-hydroxybenzotriazole as a mediator increased the compounds oxidized by laccases in olive mill wastewater.6101248125

    Complete blood count parameters as biomarkers of retinopathy of prematurity: a Portuguese multicenter study

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    Purpose: To evaluate complete blood count (CBC) parameters in the first week of life as predictive biomarkers for the development of retinopathy of prematurity (ROP). Methods: Multicenter, prospective, observational study of a cohort of preterm infants born with gestational age (GA) < 32 weeks or birth weight < 1500 g in eight Portuguese neonatal intensive care units. All demographic, clinical, and laboratory data from the first week of life were collected. Univariate logistic regression was used to assess risk factors for ROP and then multivariate regression was performed. Results: A total of 455 infants were included in the study. The median GA was 29.6 weeks, and the median birth weight was 1295 g. One hundred and seventy-two infants (37.8%) developed ROP. Median values of erythrocytes (p < 0.001), hemoglobin (p < 0.001), hematocrit (p < 0.001), mean corpuscular hemoglobin concentration (p < 0.001), lymphocytes (p = 0.035), and platelets (p = 0.003) of the group of infants diagnosed with ROP any stage were lower than those without ROP. Mean corpuscular volume (MCV) (p = 0.044), red blood cell distribution width (RDW) (p < 0.001), erythroblasts (p < 0.001), neutrophils (p = 0.030), neutrophils-lymphocytes ratio (p = 0.028), and basophils (p = 0.003) were higher in the ROP group. Higher values of MCV, erythroblasts, and basophils remained significantly associated with ROP after multivariate regression. Conclusion: In our cohort, the increase in erythroblasts, MCV, and basophils in the first week of life was significantly and independently associated with the development of ROP. These CBC parameters may be early predictive biomarkers for ROP.info:eu-repo/semantics/publishedVersio
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