Angiovision: Aortic stent-graft placement by augmented angionavigation

The endovascular treatment of abdominal aortic aneurysm (EVAR - EndoVascular Aneurism Repair) has become an alternative therapy to conventional open surgery. The objective of Angiovision project was to contribute to the improvement of EVAR procedures in terms of accuracy and customization of the interventional strategy. Our approach was mainly based on the use of patient-specific data, computer-aided endovascular navigation and numerical simulation. We proposed a new FEM-based patient-specific simulation solution to estimate the deformations caused by the introduction of stiff endovascular devices. We developed and implemented an original endovascular navigation system to augment the intraoperative fluoroscopy with the visualization of deformed preoperative aorto-iliac structure, and related information concerning vessel wall (calcifications), as well as stent-graft virtual deployment. The proposed solution, that requires only lightweight computer equipment, can be used in a standard operating room in order to optimize device placement (from a single angle of incidence). Evaluation is currently under way.     

Enzymatic synthesis of biodiesel from palm oil assisted by microwave irradiation

Optimal conditions for enzymatic synthesis of biodiesel from palm oil and ethanol were determined with lipase from Pseudomonas fluorescens immobilized on epoxy polysiloxane–polyvinyl alcohol hybrid composite under a microwave heating system. The main goal was to reduce the reaction time preliminarily established by a process of conventional heating. A full factorial design assessed the influence of ethanol-to-palm oil (8:1–16:1) molar ratio and temperature (43–57 °C) on the transesterification yield. Microwave irradiations varying from 8 to 15 W were set up according to reaction temperature. Under optimal conditions (8:1 ethanol-to-oil molar ratio at 43 °C), 97.56 % of the fatty acids present in the palm oil were converted into ethyl esters in a 12-h reaction, corresponding to a productivity of 64.2 mg ethyl esters g^?1 h^?1. This represents a sixfold increase from the process carried out under conventional heating, thus proving to be a potential tool for enhancing biochemical modification of oils and fats. In general, advantages of the new process include: (1) microwaves speed up the enzyme-catalyzed reactions; (2) there are no destructive effects on the enzyme properties, such as stability and substrate specificity, and (3) the microwave assistance allows the entire reaction volume to be heated uniformly. These bring benefits of a low energy demand and a faster conversion of palm oil into biodiesel.     

Distribution of Recombination Hotspots in the Human Genome – A Comparison of Computer Simulations with Real Data

Recombination is the main cause of genetic diversity. Thus, errors in this process can lead to chromosomal abnormalities. Recombination events are confined to narrow chromosome regions called hotspots in which characteristic DNA motifs are found. Genomic analyses have shown that both recombination hotspots and DNA motifs are distributed unevenly along human chromosomes and are much more frequent in the subtelomeric regions of chromosomes than in their central parts. Clusters of motifs roughly follow the distribution of recombination hotspots whereas single motifs show a negative correlation with the hotspot distribution. To model the phenomena related to recombination, we carried out computer Monte Carlo simulations of genome evolution. Computer simulations generated uneven distribution of hotspots with their domination in the subtelomeric regions of chromosomes. They also revealed that purifying selection eliminating defective alleles is strong enough to cause such hotspot distribution. After sufficiently long time of simulations, the structure of chromosomes reached a dynamic equilibrium, in which number and global distribution of both hotspots and defective alleles remained statistically unchanged, while their precise positions were shifted. This resembles the dynamic structure of human and chimpanzee genomes, where hotspots change their exact locations but the global distributions of recombination events are very similar.     

Facial Morphogenesis of the Earliest Europeans

The modern human face differs from that of our early ancestors in that the facial profile is relatively retracted (orthognathic). This change in facial profile is associated with a characteristic spatial distribution of bone deposition and resorption: growth remodeling. For humans, surface resorption commonly dominates on anteriorly-facing areas of the subnasal region of the maxilla and mandible during development. We mapped the distribution of facial growth remodeling activities on the 900–800 ky maxilla ATD6-69 assigned to H. antecessor, and on the 1.5 My cranium KNM-WT 15000, part of an associated skeleton assigned to African H. erectus. We show that, as in H. sapiens, H. antecessor shows bone resorption over most of the subnasal region. This pattern contrasts with that seen in KNM-WT 15000 where evidence of bone deposition, not resorption, was identified. KNM-WT 15000 is similar to Australopithecus and the extant African apes in this localized area of bone deposition. These new data point to diversity of patterns of facial growth in fossil Homo. The similarities in facial growth in H. antecessor and H. sapiens suggest that one key developmental change responsible for the characteristic facial morphology of modern humans can be traced back at least to H. antecessor.     

Cooperation in Health: Mapping Collaborative Networks on the Web

Objective

To map and investigate the relationships established on the web between leading health-research institutions around the world.

Methods

Sample selection was based on the World Health Organization (WHO) Collaborating Centres (CCs). Data on the 768 active CCs in 89 countries were retrieved from the WHO''s database. The final sample consisted of 190 institutions devoted to health sciences in 42 countries. Data on each institution''s website were retrieved using webometric techniques (interlinking), and an asymmetric matrix was generated for social network analysis.

Findings

The results showed that American and European institutions, such as the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH) and the National Institute of Health and Medical Research (INSERM), are the most highly connected on the web and have a higher capacity to attract hyperlinks. The Karolinska Institute (KI-SE) in Sweden is well placed as an articulation point between several integrants of the network and the component''s core but lacks general recognition on the web by hyperlinks. Regarding the north-south divide, Mexico and Brazil appear to be key southern players on the web. The results showed that the hyperlinks exchanged between northern and southern countries present an abysmal gap: 99.49% of the hyperlinks provided by the North are directed toward the North itself, in contrast to 0.51% that are directed toward the South. Regarding the South, its institutions are more connected to its northern partners, with 98.46% of its hyperlinks directed toward the North, and mainly toward the United States, compared with 1.54% toward southern neighbors.

Conclusion

It is advisable to strengthen integration policies on the web and to increase web networking through hyperlink exchange. In this way, the web could actually reflect international cooperation in health and help to legitimize and enhance the visibility of the many existing south-south collaboration networks.     

Sustained Reduction of the Dengue Vector Population Resulting from an Integrated Control Strategy Applied in Two Brazilian Cities

Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program.     

2-Hydroxy Arachidonic Acid: A New Non-Steroidal Anti-Inflammatory Drug

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a family of COX1 and COX2 inhibitors used to reduce the synthesis of pro-inflammatory mediators. In addition, inflammation often leads to a harmful generation of nitric oxide. Efforts are being done in discovering safer NSAIDs molecules capable of inhibiting the synthesis of pro-inflammatory lipid mediators and nitric oxide to reduce the side effects associated with long term therapies.

Methodology/Principal Findings

The analogue of arachidonic acid (AA), 2-hydroxy-arachidonic acid (2OAA), was designed to inhibit the activities of COX1 and COX2 and it was predicted to have similar binding energies as AA for the catalytic sites of COX1 and COX2. The interaction of AA and 2OAA with COX1 and COX2 was investigated calculating the free energy of binding and the Fukui function. Toxicity was determined in mouse microglial BV-2 cells. COX1 and COX2 (PGH2 production) activities were measured in vitro. COX1 and COX2 expression in human macrophage-like U937 cells were carried out by Western blot, immunocytochemistry and RT-PCR analysis. NO production (Griess method) and iNOS (Western blot) were determined in mouse microglial BV-2 cells. The comparative efficacy of 2OAA, ibuprofen and cortisone in lowering TNF-α serum levels was determined in C57BL6/J mice challenged with LPS. We show that the presence of the –OH group reduces the likelihood of 2OAA being subjected to H* abstraction in COX, without altering significantly the free energy of binding. The 2OAA inhibited COX1 and COX2 activities and the expression of COX2 in human U937 derived macrophages challenged with LPS. In addition, 2OAA inhibited iNOS expression and the production of NO in BV-2 microglial cells. Finally, oral administration of 2OAA decreased the plasma TNF-α levels in vivo.

Conclusion/Significance

These findings demonstrate the potential of 2OAA as a NSAID.     

Letter to the Editor—the Use of Micronucleus Assay on Buccal Mucosa Cells for Risk Assessment: Relevance of Cigarette Smoke and Cytogenotoxicity

Biological Trace Element Research -     

Water deficit modulates growth,morphology, and the essential oil profile in Lippia alba L. (Verbenaceae) grown in vitro

Lippia alba (Miller) N.E. Brown is an aromatic plant species of great economic importance due to the medicinal properties of its essential oils, which provide stress relief, respiratory and gastrointestinal disease control, and anti-inflammatory and natural sedative effects. The plant is also effective in biological control against various pathogens and in food preservation. Water deficit is the most critical abiotic factor limiting plant growth and morpho-physiological development, as well as production of secondary metabolism compounds. The objective of this work was to evaluate the effect of water deficit on growth, photosynthesis, essential oil profile, and the expression of genes related to the biosynthesis of these compounds in L. alba grown in vitro. Nodal segments were cultured on medium supplemented with 0, 1, 2, and 3% (w/v) polyethylene glycol for 45 days. Water stress had a negative effect on primary metabolism indicators, such as growth, leaf area, and photosynthetic rate; but a positive effect on amino acid and total protein content. Similarly, secondary metabolism exhibited an increase in linalool but a reduction in germacrene levels under water deficit. These findings provide a deeper understanding of how water deficit affects primary and secondary metabolism in L. alba, showing the potential of this medicinal species to adapt to soils with low water availability, while still being able to grow and synthesize essential oils.