Determination of sulfur dioxide in wine using a quartz crystal microbalance

A new method for the analysis of both total and bound SO2 in wine is proposed, based on a quartz crystal microbalance (QCM), and it is compared with the widely used Ripper method. The proposed method is faster than the Ripper's, and the instrumentation is either homemade or widely available. When both methods are applied to the same sample, the results obtained using the QCM method are bracketed in an interval less than one-tenth the size of that obtained using the Ripper method. Although the SO2 concentrations found using the QCM method correlate well with the ones obtained with the Ripper method, the results are systematically higher, which can be explained as due to the absence of interferences known to affect the Ripper method

Attainment of hydrogel-thickened nanoemulsions with tea tree oil (Melaleuca alternifolia) and retinyl palmitate

We propose the development of hydrogel-thickned nanoemulsions (HTNs) with tea tree essential oil (Melaleuca alternifolia) and vitamin A palmitate (retinyl palmitate). Nanoemulsions and HTNs were produced by the use of phase inversion method, employing non-ionic surfactants. As surfactant phase were used sorbitan esters and hydrogenated/ethoxylated castor oil. HTNs with drops size ranging between 86 to 96 nm were obtained, depending on the polymer used, with increased viscosity. Rheological profile of developed HTNs was determined, showing the influence of the kind of polymer used, here all presented pseudo-plastic behaviour, with different viscosity measurement.Key words: Nanoemulsion, hydrogel-thickened nanoemulsion, essential oil, phase inversion, vitamin A, retinyl palmitate, tea tree oil

Drying of enzyme immobilized on eco-friendly supports

Endophytic fungus Cercospora kikuchii lipase was immobilized on agroindustrial by-products and dried by oven, freeze and spray drying. Spray drying showed the best performance regarding the drying technologies evaluated. Microcrystalline cellulose and rice husk showed the best result since they retained almost 100% of lipase activity after drying. Immobilized derivatives obtained had decreased enzyme activity (≈ 30.0%) during a storage period of six months; and retained an average of 50.0% of the initial activity after five reuse cycles. Water content in immobilized derivatives varied between 4.2 and 6.1% and the water activities ranged from 0.14 to 0.30.Key words: Enzyme immobilization, drying, Cercospora kikuchii, agricultural by-products

Reconstruction of the yeast Snf1 kinase regulatory network reveals its role as a global energy regulator

Highly conserved among eukaryotic cells, the AMP-activated kinase (AMPK) is a central regulator of carbon metabolism. To map the complete network of interactions around AMPK in yeast (Snf1) and to evaluate the role of its regulatory subunit Snf4, we measured global mRNA, protein and metabolite levels in wild type, Δsnf1, Δsnf4, and Δsnf1Δsnf4 knockout strains. Using four newly developed computational tools, including novel DOGMA sub-network analysis, we showed the benefits of three-level ome-data integration to uncover the global Snf1 kinase role in yeast. We for the first time identified Snf1's global regulation on gene and protein expression levels, and showed that yeast Snf1 has a far more extensive function in controlling energy metabolism than reported earlier. Additionally, we identified complementary roles of Snf1 and Snf4. Similar to the function of AMPK in humans, our findings showed that Snf1 is a low-energy checkpoint and that yeast can be used more extensively as a model system for studying the molecular mechanisms underlying the global regulation of AMPK in mammals, failure of which leads to metabolic diseases

Enhancement of affective processing induced by bifrontal transcranial direct current stimulation in patients with major depression

ObjectiveOur aim was to evaluate whether one single section of transcranial direct current stimulation (tDCS), a neuromodulatory technique that noninvasively modifies cortical excitability, could induce acute changes in the negative attentional bias in patients with major depression. Subjects and MethodsRandomized, double-blind, sham-controlled, parallel design enrolling 24 age-, gender-matched, drug-free, depressed subjects. Anode and cathode were placed over the left and right dorsolateral prefrontal cortex. We performed a word Emotional Stroop Task collecting the response times (RTs) for positive-, negative-, and neutral-related words. The emotional Stroop effect for negative vs. neutral and vs. positive words was used as the measure of attentional bias. ResultsAt baseline, RTs were significantly slower for negative vs. positive words. We found that active but not sham tDCS significantly modified the negative attentional bias, abolishing slower RT for negative words. ConclusionActive but not sham tDCS significantly modified the negative attentional bias. These findings add evidence that a single tDCS session transiently induces potent changes in affective processing, which might be one of the mechanisms of tDCS underlying mood changes

Double valve replacement for acute spontaneous left chordal rupture secondary to chronic aortic incompetence

A 54 years old male with undiagnosed chronic calcific degenerative aortic valve incompetence presented with acute left anterior chordae tendinae rupture resulting in severe left heart failure and cardiogenic shock. He was successfully treated with emergency double valve replacement using mechanical valves. The pathogenesis of acute rupture of the anterior chordae tendinae, without any evidence of infective endocarditis or ischemic heart disease seems to have been attrition of the subvalvular mitral apparatus by the chronic regurgitant jet of aortic incompetence with chronic volume overload. We review the literature with specific focus on the occurrence of this unusual event

An evaluation of enteral nutrition practices and nutritional provision in children during the entire length of stay in critical care

<b>Background</b> Provision of optimal nutrition in children in critical care is often challenging. This study evaluated exclusive enteral nutrition (EN) provision practices and explored predictors of energy intake and delay of EN advancement in critically ill children.<p></p> <b>Methods</b> Data on intake and EN practices were collected on a daily basis and compared against predefined targets and dietary reference values in a paediatric intensive care unit. Factors associated with intake and advancement of EN were explored.<p></p> <b>Results</b> Data were collected from 130 patients and 887 nutritional support days (NSDs). Delay to initiate EN was longer in patients from both the General Surgical and congenital heart defect (CHD) Surgical groups [Median (IQR); CHD Surgical group: 20.3 (16.4) vs General Surgical group: 11.4 (53.5) vs Medical group: 6.5 (10.9) hours; p <= 0.001]. Daily fasting time per patient was significantly longer in patients from the General Surgical and CHD Surgical groups than those from the Medical group [% of 24 h, Median (IQR); CHD Surgical group: 24.0 (29.2) vs General Surgical group: 41.7 (66.7) vs Medical group: 9.4 (21.9); p <= 0.001]. A lower proportion of fluids was delivered as EN per patient (45% vs 73%) or per NSD (56% vs 73%) in those from the CHD Surgical group compared with those with medical conditions. Protein and energy requirements were achieved in 38% and 33% of the NSDs. In a substantial proportion of NSDs, minimum micronutrient recommendations were not met particularly in those patients from the CHD Surgical group. A higher delivery of fluid requirements (p < 0.05) and a greater proportion of these delivered as EN (p < 0.001) were associated with median energy intake during stay and delay of EN advancement. Fasting (31%), fluid restriction (39%) for clinical reasons, procedures requiring feed cessation and establishing EN (22%) were the most common reasons why target energy requirements were not met.<p></p> <b>Conclusions</b> Provision of optimal EN support remains challenging and varies during hospitalisation and among patients. Delivery of EN should be prioritized over other "non-nutritional" fluids whenever this is possible.<p></p&gt

The Dynamics of Transmission and Spatial Distribution of Malaria in Riverside Areas of Porto Velho, Rondônia, in the Amazon Region of Brazil

The study area in Rondônia was the site of extensive malaria epidemic outbreaks in the 19th and 20th centuries related to environmental impacts, with large immigration flows. The present work analyzes the transmission dynamics of malaria in these areas to propose measures for avoiding epidemic outbreaks due to the construction of two Hydroelectric Power Plants. A population based baseline demographic census and a malaria prevalence follow up were performed in two river side localities in the suburbs of Porto Velho city and in its rural vicinity. The quantification and nature of malaria parasites in clinical patients and asymptomatic parasite carriers were performed using microscopic and Real Time PCR methodologies. Anopheles densities and their seasonal variation were done by monthly captures for defining HBR (hourly biting rate) values. Main results: (i) malaria among residents show the riverside profile, with population at risk represented by children and young adults; (ii) asymptomatic vivax and falciparum malaria parasite carriers correspond to around 15% of adults living in the area; (iii) vivax malaria relapses were responsible for 30% of clinical cases; (iv) malaria risk for the residents was evaluated as 20–25% for vivax and 5–7% for falciparum malaria; (v) anopheline densities shown outdoors HBR values 5 to 10 fold higher than indoors and reach 10.000 bites/person/year; (vi) very high incidence observed in one of the surveyed localities was explained by a micro epidemic outbreak affecting visitors and temporary residents. Temporary residents living in tents or shacks are accessible to outdoors transmission. Seasonal fishermen were the main group at risk in the study and were responsible for a 2.6 fold increase in the malaria incidence in the locality. This situation illustrates the danger of extensive epidemic outbreaks when thousands of workers and secondary immigrant population will arrive attracted by opportunities opened by the Hydroelectric Power Plants constructions