Soluble inflammatory markers as predictors of virological response in patients with chronic hepatitis C virus infection treated with interferon-α plus ribavirin

The host immune response plays an important role in viral clearance in patients who are chronically infected with hepatitis C virus (HCV) and are treated with interferon and ribavirin. Activation of the immune system involves the release of pro and anti-inflammatory molecules that can be measured in plasma samples. The present study aimed to evaluate the association between pretreatment plasma levels of chemokines and soluble tumor necrosis factor receptors (sTNF-R) and the virological response in treated patients with chronic hepatitis C infection. Forty-one chronically-infected HCV patients that were being treated with interferon-α (IFN-α) plus ribavirin were included in the study. Socio-demographic, clinical and laboratory data were collected and pretreatment plasma levels of chemokine CCL2, CCL3, CCL11, CCL24, chemokine CXCL9, CXCL10, sTNF-R1 and sTNF-R2 were measured. The virological response was assessed at treatment week 12, at the end of treatment and 24 weeks after treatment. Pretreatment CXCL10 levels were significantly higher in patients without an early virological response (EVR) or sustained virological response (SVR) compared to responders [512.9 pg/mL vs. 179.1 pg/mL (p = 0.011) and 289.9 pg/mL vs. 142.7 pg/mL (p = 0.045), respectively]. The accuracy of CXCL10 as a predictor of the absence of EVR and SVR was 0.79 [confidence interval (CI) 95%: 0.59-0.99] and 0.69 (CI 95%: 0.51-0.87), respectively. Pretreatment plasma levels of the other soluble inflammatory markers evaluated were not associated with a treatment response. Pretreatment CXCL10 levels were predictive of both EVR and SVR to IFN-α and ribavirin and may be useful in the evaluation of candidates for therapy.

Immunostimulatory property of a synthetic peptide belonging to the soluble ATP diphosphohydro-lase isoform (SmATPDase 2) and immunolocalisation of this protein in the Schistosoma mansoni egg

A peptide (SmB2LJ; r175-194) that belongs to a conserved domain from Schistosoma mansoni SmATPDase 2 and is shared with potato apyrase, as predicted by in silico analysis as antigenic, was synthesised and its immunostimulatory property was analysed. When inoculated in BALB/c mice, this peptide induced high levels of SmB2LJ-specific IgG1 and IgG2a subtypes, as detected by enzyme linked immunosorbent assay. In addition, dot blots were found to be positive for immune sera against potato apyrase and SmB2LJ. These results suggest that the conserved domain r175-194 from the S. mansoni SmATPDase 2 is antigenic. Western blots were performed and the anti-SmB2LJ antibody recognised in adult worm (soluble worm antigen preparation) or soluble egg antigen antigenic preparations two bands of approximately 63 and 55 kDa, molecular masses similar to those predicted for adult worm SmATPDase 2. This finding strongly suggests the expression of this same isoform in S. mansoni eggs. To assess localisation of SmATPDase 2, confocal fluorescence microscopy was performed using cryostat sections of infected mouse liver and polyclonal antiserum against SmB2LJ. Positive reactions were identified on the external surface from the miracidium in von Lichtenberg's envelope and, in the outer side of the egg-shell, showing that this soluble isoform is secreted from the S. mansoni eggs.

Serial measurement of the circulating levels of tumour necrosis factor and its soluble receptors 1 and 2 for monitoring leprosy patients during multidrug treatment

Leprosy is an infectious and contagious spectral disease accompanied by a series of immunological events triggered by the host response to the aetiologic agent, Mycobacterium leprae . The induction and maintenance of the immune/inflammatory response in leprosy are linked to multiple cell interactions and soluble factors, primarily through the action of cytokines. The purpose of the present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages of multidrug treatment (MDT) in comparison with non-infected individuals and to determine their role as putative biomarkers of the severity of leprosy or the treatment response. ELISA was used to measure the levels of these molecules in 30 healthy controls and 37 leprosy patients at the time of diagnosis and during and after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in infected individuals in comparison with controls. The levels of TNF-α, but not sTNF-R2, decreased with treatment. The current results corroborate previous reports of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the control of this cytokine during MDT.

Availability of a soluble phosphorus source applied to soil samples with different acidicity levels

Considerations on the interactions of P in the soil-plant system have a long history, but are still topical and not yet satisfactorily understood. One concern is the effect of liming before or after application of soluble sources on the crop yield and efficiency of available P under these conditions. The aim of this study was to evaluate the effect of soil acidity on availability of P from a soluble source, based on plant growth and chemical extractants. Nine soil samples were incubated with a dose of 200 mg kg-1 P in soil with different levels of previously adjusted acidity (pH H2O 4.5; 5.0; 5.5; 6.0 and 6.5) and compared to soils without P application. After 40 days of soil incubation with a P source, each treatment was limed again so that all pH values were adjusted to 6.5 and then sorghum was planted. After the first and second liming the P levels were determined by the extractants Mehlich-1, Bray-1 and Resin, and the fractionated inorganic P forms. In general, the different acidity levels did not influence the P availability measured by plant growth and P uptake at the studied P dose. For some soils however these values increased or decreased according to the initial soil pH (from 4.5 to 6.5). Plant growth, P uptake and P extractable by Mehlich-1 and Bray-1 were significantly correlated, unlike resin-extractable P, at pH values raised to 6.5. These latter correlations were however significant before the second liming. The P contents extracted by Mehlich-1 and Bray-1 were significantly correlated with each other in the entire test range of soil acidity, even after adjusting pH to 6.5, besides depending on the soil buffering capacity for P. Resin was also sensitive to the properties that express the soil buffering capacity for P, but less clearly than Mehlich-1 and Bray-1. The application of triple superphosphate tended to increase the levels of P-Al, P-Fe and P-Ca and the highest P levels extracted by Bray-1 were due to a higher occurrence of P-Al and P-Fe in the soils.

Water-soluble nutrients in aerial plant parts of peanut and white oat as affected by lime and gypsum application

Lime and gypsum influence nutrient availability and uptake, as well as the content of organic acids in the aerial plant parts. These changes, quantified by plant analysis of soluble nutrients, may potentiate the effect of soil amendment, ensuring the sustainability of the no-tillage system. In this sense the effect of lime and gypsum surface application on the content of water-soluble nutrients in peanut and oat residues was evaluated. The experiment was conducted on an Oxisol in Botucatu (SP) in the growing seasons 2004/2005 and 2005/2006. It was arranged in a randomized block design in split plots with four replications, where lime rates represented the plots and presence or absence of gypsum application the subplots. Peanut was grown in summer and white oat in the winter in the entire experimental area. Gypsum applied to peanut increased soluble Ca only in the first season, due to the short period between product application and determination of soluble nutrient contents in the plant extract. Liming of peanut and oat increased soluble Ca, Mg, K contents, did not alter Cu content and reduced Zn, Mn and Fe contents in both years of cultivation. Gypsum on the other hand reduced the electrical conductivity of peanut (2004/2005 and 2005/2006) and white oat (2004/2005).

Soluble carbon in oxisol under the effect of organic residue rates

The application of organic residues to the soil can increase soluble organic carbon (SOC) and affect the pH and electrolytic conductivity (EC) of the soil. However, the magnitude of these changes depends on the type of residue and the applied dose. This study aimed to evaluate the effect of increasing C rates contained in organic residue on the pH, EC, water-extractable total carbon (WETC), water-extractable organic carbon (WEOC), and water-extractable inorganic carbon (WEIC) in soil treated with manure (chicken, swine, and quail), sawdust, coffee husk, and sewage sludge. The levels of total C (TC- KH2PO4), organic carbon (OC- KH2PO4), and inorganic C (IC- KH2PO4) extractable by a 0.1 mol L-1 KH2PO4 solution were also quantified in soil under the effect of increasing rates of chicken and quail manures. The following rates of organic residue C were applied to a dystrophic Red Latosol (Oxisol) sample: 0, 2,000, 5,000, 10,000, and 20,000 mg kg-1. The addition of organic residues to the soil increased pH, except in the case of sewage sludge, which acidified the soil. The acidity correction potential of chicken and quail manure was highest, dependent on the manure rate applied; regardless of the dose used, sawdust barely alters the soil pH. At all tested rates, the EC of the soil treated with swine manure, coffee husk, and sawdust remained below 2.0 dS m-1, which is a critical level for salinity-sensitive crops. However, the application of chicken or quail manure and sewage sludge at certain rates increased the EC to values above this threshold level. Highest levels of WETC, WEOC, and WEIC were obtained when chicken and quail manure and coffee husk were applied to the Oxisol. The quantities of SOC extracted by KH2PO4 were higher than the quantities extracted by water, demonstrating the ability of soil to adsorb C into its colloids.

CHARACTERIZATION OF BULK SOIL HUMIN AND ITS ALKALINE-SOLUBLE AND ALKALINE-INSOLUBLE FRACTIONS

Humic substances are the major components of soil organic matter. Among the three humic substance components (humic acid, fulvic acid, and humin), humin is the most insoluble in aqueous solution at any pH value and, in turn, the least understood. Humin has poor solubility mainly because it is tightly bonded to inorganic soil colloids. By breaking the linkage between humin and inorganic soil colloids using inorganic or organic solvents, bulk humin can be partially soluble in alkali, enabling a better understanding of the structure and properties of humin. However, the structural relationship between bulk humin and its alkaline-soluble (AS) and alkaline-insoluble (AIS) fractions is still unknown. In this study, we isolated bulk humin from two soils of Northeast China by exhaustive extraction (25 to 28 times) with 0.1 mol L-1 NaOH + 0.1 mol L-1 Na4P2O7, followed by the traditional treatment with 10 % HF-HCl. The isolated bulk humin was then fractionated into AS-humin and AIS-humin by exhaustive extraction (12 to 15 times) with 0.1 mol L-1 NaOH. Elemental analysis and solid-state 13C cross-polarization magic angle spinning nuclear magnetic resonance (13C CPMAS NMR) spectroscopy were used to characterize and compare the chemical structures of bulk humin and its corresponding fractions. The results showed that, regardless of soil types, bulk humin was the most aliphatic and most hydrophobic, AS-humin was the least aliphatic, and AIS-humin was the least alkylated among the three humic components. The results showed that bulk humin and its corresponding AS-humin and AIS-humin fractions are structurally differed from one another, implying that the functions of these humic components in the soil environment differed.

ORGANIC CARBON CONTENTS AND STOCKS IN PARTICLE SIZE FRACTIONS OF A TYPIC HAPLUDOX FERTILIZED WITH PIG SLURRY AND SOLUBLE FERTILIZER

The use of pig slurry (PS) as fertilizer can affect the soil quality and increase total stocks of soil organic carbon (TOC). However, the effects of PS on TOC amount and forms in the soil are not fully understood, particularly in areas under no-tillage (NT). The purpose of this study was to determine TOC contents and stocks in the particulate (POC) and mineral-associated C fractions (MAC) of an Oxisol after nine years of maize-oat rotation under NT, with annual applications of PS, soluble fertilizer and combined fertilization (pig slurry + soluble fertilizer). The experiment was initiated in 2001 in Campos Novos, Santa Catarina, with the following treatments: PS at rates of 0 (without fertilization - PS0); 25 (PS25); 50 (PS50); 100 (PS100); and 200 m3 ha-1yr-1 (PS200); fertilization with soluble fertilizer (SF); and mixed fertilization (PS + SF). The TOC content was determined in samples of six soil layers to a depth of 40 cm, and the POC and MAC contents in four layers to a depth of 20 cm. From the rate of 50 m3 ha-1yr-1 and upwards, the soil TOC content and stock increased according to the PS rates in the layers to a depth of 10 cm. The POC and MAC contents and stocks were higher in the surface layers, with a clear predominance of the second fraction, but a greater relative amplitude in the contents of the first fraction.

Soluble sugars and germination of Annona emarginata (Schltdl.) H. Rainer seeds submitted to immersion in GA3 up to different water contents

The objective of this study was to evaluate the effect of different water contents achieved by Annona emarginata (Schltdl.) H. Rainer seeds during immersion in GA3 solutions, in variation of soluble sugars levels and germination. Seeds with 10% of initial water content were submitted to imbibition in GA3 solutions with concentrations of 0; 250; 500; 750 and 1000 mg L-1 and when they reached the water content of 15%, 20%, 25%, 30% and 35%, the quantification of soluble sugars levels and germination test were performed. Seeds immersed up to they reach 15% of water with GA3 and immersed up to the water acquisition of 20% without GA3, presented higher soluble sugars levels and germination percentage, which were decreased when the seeds reached 30% and 35% of water, independently of the presence of the plant growth regulator. It was conclude that different water contents reached by the seeds in immersion treatments with GA3 affect the soluble sugars levels and germination percentage of Annona emarginata seeds. Thus, in treatments with Annona emarginata, the seeds must remain immersed in water without GA3 up to they reach 20% of water, as higher water contents (35%) reduce the soluble sugars levels and the seed germination percentage.

Síntese do butirato de n-butila empregando lipase microbiana imobilizada em copolímero de estireno-divinilbenzeno

This work investigates the reaction parameters of an immobilized lipase in the esterification reaction of n-butanol and butyric acid. Microbial lipase from Candida rugosa was immobilized onto styrene-divinylbenzene copolymer (STY-DVB) and subsequently introduced in an organic medium containing substrates in appropriate concentrations. Heptane was selected as solvent on the basis of its compatibility with the resin and the enzyme. The influence of molar ratio of acid to alcohol, amount of immobilized lipase and temperature on the butyl butyrate formation was determined. The results were compared with those achieved with free lipase and Lipozyme (commercially immobilized lipase) under the same operational conditions.

Efeito do polietilenoglicol e da albumina na imobilização de lipase microbiana e na catálise em meio orgânico

Poly (ethylene) glycol (PEG) and bovine serum albumin (BSA), as additive agents, were used to enhance the activity of immobilized microbial lipase in organic solvent. Controlled pore silica (CPS) was selected as matrix and different immobilization procedures were evaluated: directly lipase binding on CPS and simultaneous addition of lipase and additive agent on the same support. The highest coupling yield (59.6%) was attained when the immobilization procedure was performed at lipase loading of 150 U/g support in the presence of PEG-1.500. This immobilized system was used in esterification reactions under repeated batch cycles and the biocatalyst half-life was found to increase 2.7 times when compared with the control.

Optimisation of the lipase-catalysed preparation of a nucleoside prodrug model using an experimental design methodology

The preparation of 2', 3'-di-O-hexanoyluridine (2) by a Candida antarctica B lipase-catalysed alcoholysis of 2', 3', 5'-tri-O-hexanoyluridine (1) was optimised using an experimental design. At 25 ºC better experimental conditions allowed an increase in the yield of 2 from 80% to 96%. In addition to the yield improvement, the volume reaction could be diminished in a factor of 5 and the reaction time significantly shortened.

Determinação das propriedades catalíticas em meio aquoso e orgânico da lipase de Candida rugosa imobilizada em celulignina quimicamente modificada por carbonildiimidazol

Microbial lipase from Candida rugosa was immobilized by covalent binding on wood cellulignin (Eucaliptus grandis) chemically modified with carbonyldiimidazole. The immobilized system was fully evaluated in aqueous (olive oil hydrolysis) and organic (ester synthesis) media. A comparative study between free and immobilized lipase was carried out in terms of pH, temperature and thermal stability. A higher pH value (8.0) was found optimal for the immobilized lipase. The optimal reaction temperature shifted from 37 °C for the free lipase to 45 °C for the immobilized lipase. The pattern of heat stability indicated that the immobilization process tends to stabilize the enzyme. Kinetics tests at 37 °C following the hydrolysis of olive oil obeyed the Michaelis-Menten rate equation. Values for Km = 924.9 mM and Vmax = 198.3 U/mg were lower than for free lipase, suggesting that the affinity towards the substrate changed and the activity of the immobilized lipase decreased during the course of immobilization. The immobilized derivative was also tested in the ester synthesis from several alcohols and carboxylic acids.

Comparação do desempenho da lipase de candida rugosa imobilizada em suporte híbrido de polissiloxano-polivinilálcool empregando diferentes metodologias

The efficiency for immobilizing microbial Candida rugosa lipase on a hybrid matrix of polysiloxane polyvinyl alcohol, by adsorption, covalent coupling and encapsulation was compared. The activities of immobilized derivatives were evaluated using p-nitrophenylpalmitate (hydrolysis) and butyric acid and butanol (esterification) as substrates. Operational stability and storage tests were also performed. Among the procedures tested, the proposed matrix was efficient for immobilizing C. rugosa lipase by adsorption and covalent coupling techniques and unsuitable for encapsulation purposes. The results reveal that better catalytic properties in both aqueous and organic media were demonstrated by the covalent coupling POS-PVA immobilized lipase, including also satisfactory half-life and good storage stability.

Co-produção de lipase e biossurfactante em estado sólido para utilização em biorremediação de óleos vegetais e hidrocarbonetos

Recently lipases have been increasing in prominence due to its wide industrial application. The lipase production can be influenced by different variables such as the producing microorganism, carbon sources, aeration and agitation conditions, inductor type and the geometry of the reactor. Biosurfactants are composites of surface active produced by microbial cells which reduce superficial and interfacial tensions. The objective of this study was to verify the influence of different process variables in the lipase production during a fermentative process. The results showed that the concomitant production of lipases and biosurfactant was possible in different cultivation conditions.