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

Da caridade à solidariedade. As controvérsias públicas na construção do espaço comum – Configurações da mobilização política.

Partindo da análise das lógicas de acção caritativa, para as lógicas de acção solidária, propõem-se com esta comunicação reflectir em torno dos princípios que poderão ter contribuído para uma alteração das sensibilidades e compaixões dos cidadãos relativamente aos quadros sociais do sofrimento humano, dando lugar a diferentes quadrantes de operações criticas na prossecução de um bem comum. O sentimento de vulnerabilidade, associado às vítimas, poderá ser um dos factores promotores de diferentes interpretações críticas e manifestações colectivas de indignação que é denunciada publicamente pelos novos movimentos sociais, originando controvérsias, disputas e conflitos. As controvérsias públicas, que diferentes vocabulários de motivação conduzem os actores a associar-se, em consequência do cruzamento das intenções individuais e colectivas, perseguem um fim comum sujeito a um acordo (umas vezes mais precário, outras vezes menos precário). O tipo de acordo e as modalidades de cooperação da acção, são ingredientes fundamentais para perceber, por um lado qual a gramática política em que se baseiam na generalidade os movimentos associativos, que emergem actualmente apresentando novas práticas sociais enformadas pelos princípios da solidariedade e participação Apresenta-se pois pertinente analisar o papel das organizações da sociedade civil em contraponto com a intervenção do Estado e do Poder Político, em que as primeiras na sua acção de disputa na arena pública estão sujeitas, directa ou indirectamente, a novas formas de regulação no jogo das controvérsias, inerente ao próprio espaço público no âmbito do enquadramento da qualificação do exercício democrático

Characterization of cold-induced changes in the fatty acids profile of rice seedlings.

Rice, a staple food for more than one half of the world?s population, is one of the most cold-sensitive cereals. Breeding programs aimed at increasing rice production are expected to reduce cold-imposed grain losses. Several reports have demonstrated that cold induce differential effects on the fatty acids profile of membranes in chilling-sensitive and chilling-tolerant plants. In this work, we evaluated changes in fatty acid (FA) composition as a potential screening tool to evaluate chilling sensitivity of rice accessions. Cold exposure led to the preferential accumulation of the polyunsaturated linolenic and linoleic FAs and reduction of palmitic and stearic FAs, besides showing increased lignoceric acid content in roots of the variety. Similarly, roots of cold-exposed line Quila 66304 also presented preferential accumulation of linolenic and linoleic FAs and reduction of palmitic and stearic FAs. Cold exposure also led to enhanced levels of palmitic acid in shoots of Amaroo and, in a smaller extent, in shoots of Quila 66304. Linolenic acid was reduced in the shoots of both Amaroo and Quila 66304, while oleic acid content was reduced in shoots of Amaroo and slightly increased in shoots of Quila 66304. Double-bond index analysis indicated that 18 carbons FAs DBI for roots might be a good screening tool for cold response in rice. Results in this report demonstrate that cold-induced changes in FA profile represent a useful screening tool for early identification of differences in cold acclimation potential among rice accessions

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

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