Pulmonary valve replacement for treatment of severe pulmonary regurgitation in patients with previous tetralogy of Fallot repair surgery.

Tetralogy of Fallot was classically described as the combination of pulmonary stenosis, right ventricle hypertrophy, perimembranous ventricular septal defect and an aortic root that overrides the ventricular septal defect. Full surgical repair, which is usually indicated in toddlers, comprises closure of the ventricular septal defect and alleviation of the pulmonary stenosis. Because there is a wide anatomical spectrum, the cause and severity of the pulmonary stenosis are variable. However, when the pulmonary valve is stenotic and not well-developed, it has to be removed, and one has to accept severe pulmonary regurgitation as a sequela. In the ensuing years, when signs of damage to the right ventricle are proven, pulmonary valve replacement is indicated. We present the case of a 16-year-old patient with tetralogy of Fallot that was corrected during the first year of life. Follow-up demonstrated progressive exercise intolerance and moderate-to-severe right ventricle dilatation. Thus, surgical pulmonary valve replacement was indicated. The surgical approach was through a full median redo sternotomy. Central cardiopulmonary bypass was established with bicaval drainage. The operation was performed under assisted non-clamped circulatory support. The calcified previous pericardial patch was removed, and a 25-mm bioprosthetic valve was implanted in the pulmonary annulus. A new pericardial heterologous patch was used for the transannular pulmonary plasty.

Modeling injury rates as a function of industrialized versus on-site construction techniques.

It is often predicted that the industrialization of building activities will lead to a reduction of accident rates in the construction sector, particularly as a result of switching activities from building sites to factories. However, to date no scientific research has provided objective quantitative results to back up this claim. The aim of this paper is to evaluate how industrialization affects the accident rate in different industrialized building systems in Spain. Our results revealed that the industrialized steel modular system presents the lowest accident rate, while the highest accident rate was recorded in the construction method with cast-in-place concrete. The lightweight construction system also presents a high accident rate. Accordingly, industrialized building systems cannot claim to be safer than traditional ones. The different types of "on-site work" seem to be the main variable which would explain the accident rates recorded in industrialized construction systems.

Resistance to Tomato yellow leaf curl virus accumulation in the tomato wild relative Solanum habrochaites associated with the C4 viral protein.

Tomato yellow leaf curl disease (TYLCD) is a severe threat to tomato crops worldwide and is caused by Tomato yellow leaf curl virus (TYLCV) and several other begomoviruses (genus Begomovirus, family Geminiviridae). Host plant resistance is the best TYLCD control method but limited sources of resistance are available. In this study, two Solanum habrochaites TYLCD-resistance sources, EELM-388 and EELM-889, were found after a wide germplasm screening and were further characterized. A consistent resistance to the widely distributed strain TYLCV-IL was observed when plants were inoculated by Bemisia tabaci or by agroinoculation using an infectious clone, with no symptoms or virus accumulation observed in inoculated plants. Moreover, the resistance was effective under field conditions with high TYLCD pressure. Two independent loci, one dominant and one recessive, were associated with EELM-889 resistance. The study shows these loci to be distinct from that of the resistance gene (Ty-1 gene) commonly deployed in commercial tomato cultivars. Therefore, both kinds of resistance could be combined to provide improved resistance to TYLCD. Four additional TYLCD-associated viruses were challenged, showing that the resistance always prevented symptom expression, although systemic infection could occur in some cases. By using chimeric and mutant expression constructs, the C4 protein was shown to be associated with the ability to result in effective systemic infection.

Resistance to Cucurbit yellow stunting disorder virus in Cucumber.

Three hundred accessions of Cucumis sativus, including wild cucumbers, land races, traditional cultivars, and breeding lines, were evaluated under natural-infection conditions in order to identify potential sources of resistance to Cucurbit yellow stunting disorder virus (CYSDV). Although 100% of the susceptible control plants showed typical yellowing symptoms induced by CYSDV, another 24 C. sativus accessions showed partial or total absence of yellowing symptoms. In contrast, when CYSDV inoculation was carried out under controlled conditions, only two (A1 and A2) of these 24 accessions showed resistance to the virus. The nature of the resistance found in A1 and A2 plants was characterized by studying the pattern of virus accumulation and symptom development under controlled infection conditions, and by analyzing the possible nonpreference of Bemisia tabaci for these accessions under free-choice conditions. There was a delay in the establishment of the CYSDV infection in A1 and A2 plants which was evident shortly after inoculation and in apical leaves of the plants at long times after inoculation. Symptom severity was also less for A1 and A2 than for a susceptible control at 8 and 12 weeks postinoculation. Thus, delayed viral infection appeared to be associated with decreased symptom severity in A1 and A2 plants. Our results also showed nonpreference for plants of the A2 accession by B. tabaci, the CYSDV vector.

Melon Resistance to Cucurbit yellow stunting disorder virus Is Characterized by Reduced Virus Accumulation.

ABSTRACT The pattern of accumulation of Cucurbit yellow stunting disorder virus (CYSDV; genus Crinivirus, family Closteroviridae) RNA has been analyzed in several cucurbit accessions. In susceptible accessions of melon (Cucumis melo), cucumber (Cucumis sativus), marrow (Cucurbita maxima), and squash (Cucurbita pepo), CYSDV RNA accumulation peaked during the first to second week postinoculation in the first to third leaf above the inoculated one; younger leaves showed very low or undetectable levels of CYSDV. Three melon accessions previously shown to remain asymptomatic after CYSDV inoculation under natural conditions were also assayed for their susceptibility to CYSDV. Hybridization and reverse transcription-polymerase chain reaction (RT-PCR) analysis of noninoculated leaves showed that only one of these, C-105, remained virus-free for up to 6 weeks after whitefly inoculation. In this accession, very low CYSDV levels were detected by RT-PCR in whitefly-inoculated leaves, and therefore, multiplication or spread of CYSDV in C-105 plants appeared to remain restricted to the inoculated leaves. When C-105 plants were graft inoculated, CYSDV RNA could be detected in phloem tissues, but the systemic colonization of C-105 by CYSDV upon graft inoculation seemed to be seriously impeded. Additionally, in situ hybridization experiments showed that, after C-105 graft inoculation, only a portion of the vascular bundles in petioles and stems were colonized by CYSDV and virus could not be found in leaf veins. RT-PCR experiments using primers to specifically detect negative-sense CYSDV RNA were carried out and showed that CYSDV replication took place in graft-inoculated C-105 scions. Therefore, the resistance mechanism may involve a restriction of the virus movement in the vascular system of the plants and/or prevention of high levels of virus accumulation.

Towards an international standard on occupational health and safety management.

As a result of the need for companies to manage occupational health and safety, as well as the absence of a globally accepted international standard, numerous organisations have developed their own models in the shape of guides, standards, or guidelines. However, the resultant dispersion is creating confusion among companies, rather than making life easier for them. In this article, we look at the current situation as far as available European management systems are concerned, and the emergent trends in the development of an international standard. Moreover, we present the special case of Spain, whose broad legislation on occupational health and safety might hinder the adoption of an international model by Spanish companies.