A survey on Triatoma dimidiata in an urban area of the province of Heredia, Costa Rica

Triatoma dimidiata has been found in several cities and towns of those countries where the insect is a domestic or peridomestic pest. In Central America, urban infestations occur in the capitals of at least five countries. During 2001 and 2002 a survey was carried out in the county of San Rafael, Heredia province, located 15 km northwest of San José, capital of Costa Rica, in order to determine the degree of infestation by T. dimidiata in an entire city block. Six peridomestic colonies of the insect were detected in the backyards of eight households. The ecotopes occupied by the insects consisted of store rooms with old objects, wood piles or firewood, and chicken coops. A total of 1917 insects were found in the six foci, during two sampling periods, and a mean infection rate by Trypanosoma cruzi of 28.4% was found in 1718 insects examined. The largest colony found in one of the households yielded 872 insects that were thriving mainly at the expenses of two dogs. Opossums and adult insects were common visitors of the houses and it became evident that this marsupial is closely related to the peridomestic cycle of the Chagas disease agent. Lack of colonization of the insect inside the human dwellings is explained by the type of construction and good sanitary conditions of the houses, in contrast to the situation in most peridomiciliary areas. Stomach blood samples from the insects showed that the main hosts were, in order of decreasing frequency: rodents, dogs, fowl, humans, opossums, and cats. The fact that no indication of infection with Chagas disease could be detected in the human occupants of the infested houses, vis a vis the high infection rate in dogs, is discussed.

Athletic injuries of the extensor carpi ulnaris subsheath: MRI findings and utility of gadolinium-enhanced fat-saturated T1-weighted sequences with wrist pronation and supination

Purpose: To report the magnetic resonance imaging (MRI) findings in athletic injuries of the extensor carpi ulnaris (ECU) subsheath, assessing the utility of gadolinium-enhanced (Gd) fat-saturated (FS) T1-weighted sequences with wrist pronation and supination. Methods and Materials: Sixteen patients (13 males, 3 females; mean age 30.3 years) with athletic injuries of the ECU subsheath sustained between January 2003 and June 2009 were included in this retrospective study. Initial and follow‑up 1.5-T wrist MRIs were performed with transverse T1-weighted and STIR sequences in pronation, and Gd FS T1-weighted sequences with wrist pronation and supination. Two radiologists assessed the type of injury (A to C), ECU tendon stability, associated lesions and rated pulse sequences using a three-point scale: 1 = poor, 2 = good and 3 = excellent. Results: Gd-enhanced FS T1-weighted transverse sequences in supination (2.63) and pronation (2.56) were most valuable, compared with STIR (2.19) and T1 weighted (1.94). Nine type A, one type B and six type C injuries were found. There were trends towards diminution in size, signal intensity and enhancement of associated pouches on follow‑up MRI and tendon stabilisation within the ulnar groove. Conclusion: Gd-enhanced FS T1-weighted sequences with wrist pronation and supination are most valuable in assessing and follow‑up athletic injuries of the ECU subsheath on 1.5-T MRI.

Protease-activated receptors and inflammatory hyperalgesia

Recent advances in basic science pointed to a role for proteinases, through the activation of proteinase-activated receptors (PARs) in nociceptive mechanisms. Activation of PAR1, PAR2 and PAR4 either by proteinases or by selective agonists causes inflammation inducing most of the cardinal signs of inflammation: swelling, redness, and pain. Sub-inflammatory doses of PAR2 agonist still induced hyperalgesia and allodynia while PAR2 has been shown to be implicated in the generation of hyperalgesia in different inflammatory models. In contrast, sub-inflammatory doses of PAR1 increases nociceptive threshold, inhibiting inflammatory hyperalgesia, thereby acting as an analgesic agent. PARs are present and functional on sensory neurons, where they participate either directly or indirectly to the transmission and/or inhibition of nociceptive messages. Taken together, the results discussed in this review highlight proteinases as signaling molecules to sensory nerves. We need to consider proteinases and the receptors that are activated by proteinases as important potential targets for the development of analgesic drugs in the treatment of inflammatory pain.

Smart Schools = Smart Economy

Ireland’s national recovery will be rooted in further developing our outstanding education system. Schools and colleges are key contributors to economic growth and national competitiveness, providing successive generations with the skills and abilities necessary for a vibrant economy and inclusive society. Within the educational system, teachers play a central role in developing the potential of our children and young people. Our education system must continue to be responsive to and supportive of the economic life of this country.

Freshwater sponge spicules: a new agent of ocular pathology

In a recent outbreak of human ocular injuries that occurred in the town of Araguatins, at the right bank of Araguaia river, state of Tocantins, Brazil, along the low water period of 2005, two patients (8 and 12-year-old boys) presented inferior adherent leukoma in the left eye (OS), and peripherical uveites, with snowbanking in the inferior pars plana. The third one (13-year-old girl) showed posterior uveites in OS, also with snowbanking. Histopathological analysis of lensectomy material from the three patients and vitrectomy from the last one revealed several silicious spicules (gemmoscleres) of the freshwater sponges Drulia uruguayensis and D. ctenosclera. This work brings material evidences, for the first time in the literature, that freshwater sponge spicules may be a surprising new etiological agent of ocular pathology.

Functional complementation of a yeast knockout strain by Schistosoma mansoni Rho1 GTPase in the presence of caffeine, an agent that affects mutants defective in the protein kinase C signal transduction pathway

In a previous study, the Schistosoma mansoni Rho1 protein was able to complement Rho1 null mutant Saccharomyces cerevisiae cells at restrictive temperatures and under osmotic stress (low calcium concentration) better than the human homologue (RhoA). It is known that under osmotic stress, the S. cerevisiae Rho1 triggers two distinct pathways: activation of the membrane 1,3-beta-glucan synthase enzymatic complex and activation of the protein kinase C1 signal transduction pathway, promoting the transcription of response genes. In the present work the SmRho1 protein and its mutants smrho1E97P, smrho1L101T, and smrho1E97P, L101T were used to try to clarify the basis for the differential complementation of Rho1 knockout yeast strain by the human and S. mansoni genes. Experiments of functional complementation in the presence of caffeine and in the presence of the osmotic regulator sorbitol were conducted. SmRho1 and its mutants showed a differential complementation of the yeast cells in the presence of caffeine, since smrho1E97P and smrho1E97P, L101T mutants showed a delay in the growth when compared to the yeast complemented with the wild type SmRho1. However, in the presence of sorbitol and caffeine the wild type SmRho1 and mutants showed a similar complementation phenotype, as they allowed yeast growth in all caffeine concentrations tested.

Representing diffusion MRI in 5D for segmentation of white matter tracts with a level set method.

We present a method for segmenting white matter tracts from high angular resolution diffusion MR. images by representing the data in a 5 dimensional space of position and orientation. Whereas crossing fiber tracts cannot be separated in 3D position space, they clearly disentangle in 5D position-orientation space. The segmentation is done using a 5D level set method applied to hyper-surfaces evolving in 5D position-orientation space. In this paper we present a methodology for constructing the position-orientation space. We then show how to implement the standard level set method in such a non-Euclidean high dimensional space. The level set theory is basically defined for N-dimensions but there are several practical implementation details to consider, such as mean curvature. Finally, we will show results from a synthetic model and a few preliminary results on real data of a human brain acquired by high angular resolution diffusion MRI.

OER in Portugal as agent of curriculum innovation and technological change. Inducing practices of "new" teaching standards

This research project aimed the following goal: promote the creation, use and disclosure of OER in a Group of Schools, involving schools and teachers from different learning levels, expecting to test and validate the use of OER, in a learning-teaching model towards curricular innovation. Defining as a starting point different subjects and teachers from distinct academic areas, we have implemented a set of activities leading to the creation of OER supported, when possible, in FLOSS tools. We adopted an action research methodology with a dual purpose: to act within a community of teachers and students, while increasing at the same time their knowledge, as well as the researcher's. The activity was developed cooperatively in order to process a certain reality of the teaching-learning process, through practical/reflective action towards it and inducing its implementation by others in the Portuguese School System, based on the production and sharing OER.

Experimental infection of dogs with a Brazilian strain of Rickettsia rickettsii: clinical and laboratory findings

The bacterium Rickettsia rickettsii is the etiological agent of an acute, severe disease called Rocky Mountain spotted fever in the United States or Brazilian spotted fever (BSF) in Brazil. In addition to these two countries, the disease has also been reported to affect humans in Mexico, Costa Rica, Panama, Colombia and Argentina. Like humans, dogs are also susceptible to R. rickettsii infection. However, despite the wide distribution of R. rickettsii in the Western Hemisphere, reports of R. rickettsii-induced illness in dogs has been restricted to the United States. The present study evaluated the pathogenicity for dogs of a South American strain of R. rickettsii. Three groups of dogs were evaluated: group 1 (G1) was inoculated ip with R. rickettsii; group 2 (G2) was infested by R. rickettsii-infected ticks; and the control group (G3) was infested by uninfected ticks. During the study, no clinical abnormalities, Rickettsia DNA or R. rickettsii-reactive antibodies were detected in G3. In contrast, all G1 and G2 dogs developed signs of rickettsial infection, i.e., fever, lethargy, anorexia, ocular lesions, thrombocytopenia, anemia and detectable levels of Rickettsia DNA and R. rickettsii-reactive antibodies in their blood. Rickettsemia started 3-8 days after inoculation or tick infestation and lasted for 3-13 days. Our results indicate that a Brazilian strain of R. rickettsii is pathogenic for dogs, suggesting that canine clinical illness due to R. rickettsii has been unreported in Brazil and possibly in the other South American countries where BSF has been reported among humans.