Behavioural alterations are independent of sickness behaviour in chronic experimental Chagas disease

The existence of the nervous form of Chagas disease is a matter of discussion since Carlos Chagas described neurological disorders, learning and behavioural alterations in Trypanosoma cruzi-infected individuals. In most patients, the clinical manifestations of the acute phase, including neurological abnormalities, resolve spontaneously without apparent consequence in the chronic phase of infection. However, chronic Chagas disease patients have behavioural changes such as psychomotor alterations, attention and memory deficits, and depression. In the present study, we tested whether or not behavioural alterations are reproducible in experimental models. We show that C57BL/6 mice chronically infected with the Colombian strain of T. cruzi (150 days post-infection) exhibit behavioural changes as (i) depression in the tail suspension and forced swim tests, (ii) anxiety analysed by elevated plus maze and open field test sand and (iii) motor coordination in the rotarod test. These alterations are neither associated with neuromuscular disorders assessed by the grip strength test nor with sickness behaviour analysed by temperature variation sand weight loss. Therefore, chronically T. cruzi-infected mice replicate behavioural alterations (depression and anxiety) detected in Chagas disease patients opening an opportunity to study the interconnection and the physiopathology of these two biological processes in an infectious scenario.

Direct cost of connecting, maintaining and disconnecting patient-controlled analgesia pump

Quantitative research that aimed to identify the mean total cost (MTC) of connecting, maintaining and disconnecting patient-controlled analgesia pump (PCA) in the management of pain. The non-probabilistic sample corresponded to the observation of 81 procedures in 17 units of the Central Institute of the Clinics Hospital, Faculty of Medicine, University of Sao Paulo. We calculated the MTC multiplying by the time spent by nurses at a unit cost of direct labor, adding the cost of materials and medications/solutions. The MTC of connecting was R$ 107.91; maintenance R$ 110.55 and disconnecting R$ 4.94. The results found will subsidize discussions about the need to transfer money from the Unified Health System to hospitals units that perform this technique of analgesic therapy and it will contribute to the cost management aimed at making efficient and effective decision-making in the allocation of available resources.

Direct Cost of Reprocessing Cotton-woven Surgical Drapes: a Case Study

OBJECTIVE Identify the direct cost of reprocessing double and single cotton-woven drapes of the surgical LAP package. METHOD A quantitative, exploratory and descriptive case study, performed at a teaching hospital. The direct cost of reprocessing cotton-woven surgical drapes was calculated by multiplying the time spent by professionals involved in reprocessing the unit with the direct cost of labor, adding to the cost of materials. The Brazilian currency (R$) originally used for the calculations was converted to US currency at the rate of US$0.42/R$. RESULTS The average total cost for surgical LAP package was US$9.72, with the predominance being in the cost of materials (US$8.70 or 89.65%). It is noteworthy that the average total cost of materials was mostly impacted by the cost of the cotton-woven drapes (US$7.99 or 91.90%). CONCLUSION The knowledge gained will subsidize discussions about replacing reusable cotton-woven surgical drapes for disposable ones, favoring arguments regarding the advantages and disadvantages of this possibility considering human resources, materials, as well as structural, environmental and financial resources.

Elephant grass genotypes for bioenergy production by direct biomass combustion

The objective of this work was to evaluate elephant grass (Pennisetum purpureum Schum.) genotypes for bioenergy production by direct biomass combustion. Five elephant grass genotypes grown in two different soil types, both of low fertility, were evaluated. The experiment was carried out at Embrapa Agrobiologia field station in Seropédica, RJ, Brazil. The design was in randomized complete blocks, with split plots and four replicates. The genotypes studied were Cameroon, Bag 02, Gramafante, Roxo and CNPGL F06-3. Evaluations were made for biomass production, total biomass nitrogen, biomass nitrogen from biological fixation, carbon/nitrogen and stem/leaf ratios, and contents of fiber, lignin, cellulose and ash. The dry matter yields ranged from 45 to 67 Mg ha-1. Genotype Roxo had the lowest yield and genotypes Bag 02 and Cameroon had the highest ones. The biomass nitrogen accumulation varied from 240 to 343 kg ha-1. The plant nitrogen from biological fixation was 51% in average. The carbon/nitrogen and stem/leaf ratios and the contents of fiber, lignin, cellulose and ash did not vary among the genotypes. The five genotypes are suitable for energy production through combustion.

Impact of direct seeding mulch-based cropping systems on soil nematodes in a long-term experiment in Madagascar

The objective of this work was to assess the effects of conventional tillage and of different direct seeding mulch-based cropping systems (DMC) on soil nematofauna characteristics. The long-term field experiment was carried out in the highlands of Madagascar on an andic Dystrustept soil. Soil samples were taken once a year during three successive years (14 to 16 years after installation of the treatments) from a 0-5-cm soil layer of a conventional tillage system and of three kinds of DMC: direct seeding on mulch from rotation soybean-maize residues; direct seeding of maize-maize rotation on living mulch of silverleaf (Desmodium uncinatum); direct seeding of bean (Phaseolus vulgaris)-soybean rotation on living mulch of kikuyu grass (Pennisetum clandestinum). The samples were compared with samples from natural fallows. The soil nematofauna, characterized by the abundance of different trophic groups and indices (MI, maturity index; EI and SI, enrichment and structure indices), allowed the discrimination of the different cropping systems. The different DMC treatments had a more complex soil food web than the tillage treatment: SI and MI were significantly greater in DMC systems. Moreover, DMC with dead mulch had a lower density of free-living nematodes than DMC with living mulch, which suggested a lower microbial activity.

Prediction of direct and indirect genetic gains and genotypic correlations in rubber tree progenies

The objective of this work was to estimate the genetic parameters, genotypic and phenotypic correlations, and direct and indirect genetic gains among and within rubber tree (Hevea brasiliensis) progenies. The experiment was set up at the Municipality of Jaú, SP, Brazil. A randomized complete block design was used, with 22 treatments (progenies), 6 replicates, and 10 plants per plot at a spacing of 3x3 m. Three‑year‑old progenies were assessed for girth, rubber yield, and bark thickness by direct and indirect gains and genotypic correlations. The number of latex vessel rings showed the best correlations, correlating positively and significantly with girth and bark thickness. Selection gains among progenies were greater than within progeny for all the variables analyzed. Total gains obtained were high, especially for girth increase and rubber yield, which were 93.38 and 105.95%, respectively. Young progeny selection can maximize the expected genetic gains, reducing the rubber tree selection cycle.

Efeitos dos parâmetros operacionais na fotodegradação do azo corante direct red 23 na interface dióxido de titânio/água

The decolorization and degradation of direct red 23 azo dye have been investigated in aqueous suspension of titanium dioxide under artificial irradiation. The effects of some operational parameters such as azo dye concentration, catalyst loading, and solution pH were investigated at 30.0 ºC and optimized values were obtained. The first-order kinetic model was used to discuss the results. The UV-Vis spectra changes showed that the azo dye sample, collected after 6 h irradiation, was 98% decolorized while the residual total carbon was 97.9% degraded, indicating simultaneous photodecolorization and degradation.

An easy and direct method for the synthesis of 1,2,4-triazole derivatives through carboxylic acids and hydrazinophthalazine

We have developed an easy method for the synthesis of thirteen compounds derived from 1,2,4-triazoles through a carboxylic acid and hydrazinophthalazine reaction, with a 75-85% yield mediated by the use of agents such as 1-ethyl-3-(3'-dimethylaminopropyl)-carbodiimide hydrochloride and 1-hydroxybenzotriazole. The operational simplicity of this method and the good yield of products make it valuable for the synthesis of new compounds with pharmacological activity.

A comparison of electrodeposited Ti/β-PbO2 and Ti-Pt/β-PbO2 anodes in the electrochemical degradation of the direct yellow 86 dye

The electrochemical performance of electrodeposited Ti/β-PbO2 and Ti-Pt/β-PbO2 anodes was galvanostatically evaluated (batch mode, 50 mA cm-2) to degrade the Direct Yellow 86 dye (100 or 200 mg L-1 in 0.1 mol L-1 Na2SO4 + 1.5 g L-1 NaCl), investigating the effect of pH and temperature. Similar results were obtained for both electrodes and the best conditions for removal of color and chemical oxygen demand are pH 7 and 40 °C, when 90% decolorization is attained by passing a charge of only ~0.13 A h L-1 and total mineralization is achieved with expenditure of ~5 kW h m-3.

Influence of chloride-mediated oxidation on the electrochemical degradation of the direct black 22 dye using boron-doped diamond and β-PbO2 anodes

The Direct Black 22 dye was electrooxidized at 30 mA cm-2 in a flow cell using a BDD or β-PbO2 anode, varying pH (3, 7, 11), temperature (10, 25, 45 °C), and [NaCl] (0 or 1.5 g L-1). In the presence of NaCl, decolorization rates were similar for all conditions investigated, but much higher than predicted through a theoretical model assuming mass-transport control; similar behavior was observed for COD removal (at pH 7, 25 °C), independently of the anode. With no NaCl, COD removals were also higher than predicted with a theoretical model, which suggests the existence of distinct dye degradation pathways.

APARATO ELETROQUÍMICO PARA SISTEMA DE AQUISIÇÃO DE DADOS MULTICANAL COM RESOLUÇÃO ESPAÇO-TEMPORAL

Spatiotemporal pattern formation in reaction-transport systems takes place spontaneously when the system is kept far from thermodynamic equilibrium. Targets, reaction fronts, waves, spirals, spots and stripes are some typical examples of selforganized structuring. In electrochemical systems, monitoring spatiotemporal patterns of potential in the solid/liquid interface can be done by the use of equally distributed microprobes located close to the working electrode. However, the physical size of each probe can limit the spatial resolution and alter mass transport properties. In contrast, the direct measurement of discrete electrodes does not suffer from this limitation and allows the accurate manipulation of the spatial coupling through changes in resistors connected to the electric circuit. In this paper, the development of an electrochemical setup for multichannel data acquisition with spatiotemporal resolution is described, especially to monitor low levels of currents usually observed in the electro-oxidation of small organic molecules.

DIRECT INFUSION ESI-MS APPLIED IN THE DETECTION OF BYPRODUCTS DUE TO REDUCTIVE DEGRADATION OF ACETAMIPRID BY ZERO-VALENT IRON

This study investigated the reductive degradation of acetamiprid (5 mg L-1) in aqueous medium (at pH 2.0) induced by zero-valent iron (50 mg). The process was monitored using high-performance liquid chromatography (HPLC) to determine the degradation rate as a function of reaction time, and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) to search for (and potentially characterize) any possible byproducts formed during degradation. The results obtained via HPLC showed that after 60 min, the degradation of the substrate reached nearly 100% in an acidic medium, whereas the mineralization rate (as determined by total organic carbon measurements) was as low as 3%. Data obtained by DI-ESI-MS showed that byproducts were formed mainly by insertions of hydrogen atoms into the nitrile, imine, and pyridine ring moieties, in addition to the observation of chlorine substitution by hydrogen replacement (hydrodechlorination) reactions.

Print-capture PCR for detection of tomato begomoviruses from plants and whiteflies

Print-capture (PC) Polymerase chain reaction (PCR) was evaluated as a novel detection method of plant viruses. Tomato (Lycopersicon esculentum) plants infected with begomovirus (fam. Geminiviridae, gen. Begomovirus) and viruliferous whiteflies were used to study the efficiency of the method. Print-capturing steps were carried out using non-charged nylon membrane or filter paper as the solid support for DNA printings. Amplified DNA fragments of expected size were consistently obtained by PCR from infected plants grown in a greenhouse, after direct application of printed materials to the PCR mix. However, virus detection from a single whitefly and from field-grown tomato samples required a high temperature treatment of printed material prior to PCR amplification. Comparison of nylon membrane and filter paper as the solid support revealed the higher efficiency of the nylon membrane. The application of print-capture PCR reduces the chances of false-positive amplification by reducing manipulation steps during preparation of the target DNA. This method maintains all the advantages of PCR diagnosis, such as the high sensitivity and no requirement of radioactive reagents.

A direct potentiometric titration study of the dissociation of humic acid with selectively blocked functional groups

A direct potentiometric titration method was applied to commercial and soil humic acids in order to determine their carboxyl and phenol group concentrations and apparent and intrinsic pK. In that context, acid-base properties of humic acids are interpreted by selective blocking of carboxylic and phenolic groups by esterification and acetylation. Differences in underivatized and derivatized HA's acid-base properties are ascribed to carboxyl and phenol groups influence on total humic acidity. Potentiometric data were treated with the modified Henderson-Hasselbalch equation. Infra red results, the acidic group contents and the average values of apparent and intrinsic pK for underivatized and derivatized HAs confirmed the selectivity of esterification derivatization method. After blocking of the functional groups, the values of acidic group contents decreased, while the value of apparent pK increased after derivatization. Phenol groups cannot be specifically identified by the acetylation method, due to low selectivity of the acetylation method.