Determinação de ph e potássio em solos do meio norte de mato grosso utilizando eletrodos seletivos de íons

Amostragens de solo em grades regulares na agricultura de precisão são comumente utilizadas comercialmente em campos na região meio norte de Mato Grosso com sucesso. Porém, a confiabilidade dos mapas depende muito da densidade amostral, sendo mais confiáveis quando são mais intensivamente amostrados. Além da limitação técnica da utilização da krigagem com poucos pontos, existe uma necessidade de baratear o custo laboratorial de amostragens intensas. Neste sentido, o objetivo desde trabalho foi determinar o teor de pH e potássio em solos utilizando eletrodos seletivos de íons e também realizar uma comparação de mapas gerados por amostras laboratoriais convencionais comparadas com amostras medidas com eletrodos seletivos de íons. Foram realizadas amostragens em grades regulares de 4 ha em talhões no meio norte de Mato Grosso tentando cobrir uma amplitude de solos representativos da região, sendo realizadas 9 subamostras em cada 4 ha. As amostras foram enviadas para laboratório comercial e também realizadas medidas diretas com eletrodos de íons seletivos em bancada. Resultados preliminares mostram boas correlações entre os métodos, sendo r=0.56 e 0.61, para pH e potássio, respectivamente. Comparações espaciais mostram que além da similaridade entre os mapas houve uma tendência de suavização dos valores para medições feitas com os eletrodos, mostrando mais coerência das manchas dos teores no solo

Structural Analysis of Fungal Cerebrosides

Of the ceramide monohexosides (CMHs), gluco- and galactosyl-ceramides are the main neutral glycosphingolipids expressed in fungal cells. Their structural determination is greatly dependent on the use of mass spectrometric techniques, including fast atom bombardment-mass spectrometry, electrospray ionization, and energy collision-induced dissociation mass spectrometry. Nuclear magnetic resonance has also been used successfully. Such a combination of techniques, combined with classical analytical separation, such as high-performance thin layer chromatography and column chromatography, has led to the structural elucidation of a great number of fungal CMHs. The structure of fungal CMH is conserved among fungal species and consists of a glucose or galactose residue attached to a ceramide moiety containing 9-methyl-4,8-sphingadienine with an amidic linkage to hydroxylated fatty acids, most commonly having 16 or 18 carbon atoms and unsaturation between C-3 and C-4. Along with their unique structural characteristics, fungal CMHs have a peculiar subcellular distribution and striking biological properties. Fungal cerebrosides were also characterized as antigenic molecules directly or indirectly involved in cell growth or differentiation in Schizophyllum commune, Cryptococcus neoformans, Pseudallescheria boydii, Candida albicans, Aspergillus nidulans, Aspergillus fumigatus, and Colletotrichum gloeosporioides. Besides classical techniques for cerebroside (CMH) analysis, we now describe new approaches, combining conventional thin layer chromatography and mass spectrometry, as well as emerging technologies for subcellular localization and distribution of glycosphingolipids by secondary ion mass spectrometry and imaging matrix-assisted laser desorption ionization time-of-flight

Structural Characterization and Anti-HSV-1 and HSV-2 Activity of Glycolipids from the Marine Algae Osmundaria obtusiloba Isolated from Southeastern Brazilian Coast

Glycolipids were extracted from the red alga Osmundaria obtusiloba from Southeastern Brazilian coast. The acetone insoluble material was extracted with chloroform/methanol and the lipids, enriched in glycolipids, were fractionated on a silica gel column eluted with chloroform, acetone and then methanol. Three major orcinol-positive bands were found in the acetone and methanol fractions, being detected by thin layer chromatography. The structures of the corresponding glycolipids were elucidated by ESI-MS and 1H/13C NMR analysis, on the basis of their tandem-MS behavior and HSQC, TOCSY fingerprints. For the first time, the structure of sulfoquinovosyldiacylglycerol from the red alga Osmundaria obtusiloba was characterized. This molecule exhibited potent antiviral activity against HSV-1 and HSV-2 with EC50 values of 42 µg/mL to HSV-1 and 12 µg/mL to HSV-2, respectively. Two other glycolipids, mono- and digalactosyldiacylglycerol, were also found in the alga, being characterized by ESI-MS/MS. The structural elucidation of algae glycolipids is a first step for a better understanding of the relation between these structures and their biological activities

Rhamnogalacturonan from Ilex paraguariensis: A potential adjuvant in sepsis treatment

AbstractThe present study evaluated the anti-inflammatory activity of a polysaccharide from maté, using a clinically relevant model of sepsis induced by cecal ligation and puncture (CLP). A polysaccharide from maté (SPI) was obtained from aqueous extraction followed by fractionation, being identified as a rhamnogalacturonan with a main chain of →4)-6-OMe-α-d-GalpA-(1→ groups, interrupted by α-l-Rhap units, substituted by a type I arabinogalactan. SPI was tested against induced-polymicrobial sepsis, at doses of 3, 7 and 10mg/kg. Via oral administration, SPI prevented the late mortality of infected mice by a rate of 60% at 10mg/kg, in comparison with untreated mice Dexamethasone, used as positive control, was slightly less effective, with an overall survival rate of 16.7% of mice at the end of the observation period. SPI also affected neutrophil influx, avoiding its accumulation in lungs, and significantly decreased tissue expression of iNOS and COX-2. In this context, maté is a potential nutraceutical, and its polysaccharide a promising adjuvant for sepsis treatment, being consumed as tea-like beverages with no related adverse effects

Human (α2→6) and Avian (α2→3) Sialylated Receptors of Influenza A Virus Show Distinct Conformations and Dynamics in Solution

Differential interactions between influenza A virus protein hemagglutinin (HA) and α2→3 (avian) or α2→6 (human) sialylated glycan receptors play an important role in governing host specificity and adaptation of the virus. Previous analysis of HA–glycan interactions with trisaccharides showed that, in addition to the terminal sialic acid linkage, the conformation and topology of the glycans, while they are bound to HA, are key factors in regulating these interactions. Here, the solution conformation and dynamics of two representative avian and human glycan pentasaccharide receptors [LSTa, Neu5Ac-α(2→3)-Gal-β(1→3)-GlcNAc-β(1→3)-Gal-β(1→4)-Glc; LSTc, (Neu5Ac-α(2→6)-Gal-β(1→4)-GlcNAc-β(1→3)-Gal-β(1→4)-Glc] have been explored using nuclear magnetic resonance and molecular dynamics simulation. Analyses demonstrate that, in solution, human and avian receptors sample distinct conformations, topologies, and dynamics. These unique features of avian and human receptors in solution could represent distinct molecular characteristics for recognition by HA, thereby providing the HA–glycan interaction specificity in influenza.Finlombardia SPAConselho Nacional de Pesquisas (Brazil)National Institutes of Health (U.S.) (R37 GM057073-13)Singapore. National Research Foundation (Singapore-MIT Alliance for Research and Technology

Ilex paraguariensis extract as drugs alternative for pain

Pain is a common and distressing symptom of many diseases and its clinical treatment generally involves analgesics and anti-inflammatory drugs. This study evaluated the toxicity of Ilex paraguariensis A. St.-Hil. (Aquifoliaceae) aqueous extract (leaves, petioles and branches) and its performance in nociceptive response. Hepatotoxicity, psychostimulant test and evaluation of enzyme markers for liver damage were also tested. Chromatographic analysis by UPLC-MS demonstrated a series of isomeric monocaffeoylquinic acids, isomers of dicaffeoylquinic acids, flavonol glycosides, and saponins. Phase I and II of nociception were obtained for meloxicam, dexamethasone and aqueous Ilex paraguariensis extract. Ilex paraguariensis extract concentration was negatively correlated (R = –0.887) with alanine aminotransferase (p < 0.05) in acetaminophen-induced hepatotoxicity test, indicating an hepatoprotective activity of this extract. Ilex paraguariensis extract also presented analgesic properties equivalent to drugs that already have proven efficacy. Notably, administration of multiple doses of Ilex paraguariensis extract was considered safe from the therapeutic point of view

Low molecular weight heparins: Structural differentiation by spectroscopic and multivariate approaches

Various branded low molecular weight heparins (LMWHs) have been used for the treatment and prevention of thrombotic for over 20 years. With the introduction of generic LMWHs and the recent events involving heparin contamination, a great deal of effort is being expended in investigating ways of monitoring and regulating this class of complex drugs. in this paper, we present the characterization of different forms of LMWHs, as well as the comparison of 5 enoxaparin copies from different manufactures. the data suggests that, while some of these drugs are structurally comparable, specific analytical methods as well as biological and pharmacological tests may be used to address their similarity, quality and potential interchangeability. the proposed approach may also be useful in comparing biosimilar and branded LMWHs. (C) 2011 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, SP, BrazilUniv Liverpool, Sch Biol Sci, Liverpool L69 7ZB, Merseyside, EnglandLoyola Univ, Med Ctr, Dept Pathol, Maywood, IL 60153 USAUniv Fed Parana, Lab Quim Carboidratos, Dept Bioquim & Biol Mol, BR-81531980 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, Dept Bioquim, BR-04044020 São Paulo, SP, BrazilWeb of Scienc