Importance of salt fingering for new nitrogen supply in the oligotrophic ocean.

The input of new nitrogen into the euphotic zone constrains the export of organic carbon to the deep ocean and thereby the biologically mediated long-term CO2 exchange between the ocean and atmosphere. In low-latitude open-ocean regions, turbulence-driven nitrate diffusion from the ocean’s interior and biological fixation of atmospheric N2 are the main sources of new nitrogen for phytoplankton productivity. With measurements across the tropical and subtropical Atlantic, Pacific and Indian oceans, we show that nitrate diffusion (171±190 mmolm 2 d 1) dominates over N2 fixation (9.0±9.4 mmolm 2 d 1) at the time of sampling. Nitrate diffusion mediated by salt fingers is responsible for ca. 20% of the new nitrogen supply in several provinces of the Atlantic and Indian Oceans. Our results indicate that salt finger diffusion should be considered in present and future ocean nitrogen budgets, as it could supply globally 0.23–1.00 TmolNyr 1 to the euphotic zone.MALASPINA (CSD2008-00077)Versión del editor10,015

Control of Visceral Leishmaniasis in Latin America—A Systematic Review

Visceral leishmaniasis is a vector-borne disease characterized by fever, spleen and liver enlargement, and low blood cell counts. In the Americas VL is zoonotic, with domestic dogs as main animal reservoirs, and is caused by the intracellular parasite Leishmania infantum (syn. Leishmania chagasi). Humans acquire the infection through the bite of an infected sand fly. The disease is potentially lethal if untreated. VL is reported from Mexico to Argentina, with recent trends showing a rapid spread in Brazil. Control measures directed against the canine reservoir and insect vectors have been unsuccessful, and early detection and treatment of human cases remains as the most important strategy to reduce case fatality. Well-designed studies evaluating diagnosis, treatment, and prevention/control interventions are scarce. The available scientific evidence reasonably supports the use of rapid diagnostic tests for the diagnosis of human disease. Properly designed randomized controlled trials following good clinical practices are needed to inform drug policy. Routine control strategies against the canine reservoirs and insect vectors are based on weak and conflicting evidence, and vector control strategies and vaccine development should constitute research priorities

Transgenic Potatoes for Potato Cyst Nematode Control Can Replace Pesticide Use without Impact on Soil Quality

Current and future global crop yields depend upon soil quality to which soil organisms make an important contribution. The European Union seeks to protect European soils and their biodiversity for instance by amending its Directive on pesticide usage. This poses a challenge for control of Globodera pallida (a potato cyst nematode) for which both natural resistance and rotational control are inadequate. One approach of high potential is transgenically based resistance. This work demonstrates the potential in the field of a new transgenic trait for control of G. pallida that suppresses root invasion. It also investigates its impact and that of a second transgenic trait on the non-target soil nematode community. We establish that a peptide that disrupts chemoreception of nematodes without a lethal effect provides resistance to G. pallida in both a containment and a field trial when precisely targeted under control of a root tip-specific promoter. In addition we combine DNA barcoding and quantitative PCR to recognise nematode genera from soil samples without microscope-based observation and use the method for nematode faunal analysis. This approach establishes that the peptide and a cysteine proteinase inhibitor that offer distinct bases for transgenic plant resistance to G. pallida do so without impact on the non-target nematode soil community

Avaliação do sistema de pontuação para o diagnóstico da tuberculose na infância preconizado pelo Ministério da Saúde, Brasil Evaluation of a scoring system recommended by the Brazilian Ministry of Health for the diagnosis of childhood tuberculosis

A tuberculose é conhecida como uma das mais importantes causas de mortalidade no mundo. O diagnóstico da tuberculose na infância tem entre suas muitas dificuldades o achado bacteriológico do Mycobacterium tuberculosis. Este foi um estudo de caso-controle aninhado em uma coorte prospectiva com crianças que coletaram lavado gástrico em nível ambulatorial e hospitalar, com o objetivo de identificar se o sistema de pontuação para o diagnóstico de tuberculose em crianças negativas à baciloscopia, proposto pelo Ministério da Saúde, poderia ser utilizado como instrumento inicial de identificação do diagnóstico da tuberculose na infância. Um total de 108 crianças foi submetido ao lavado gástrico, sendo que 53 tiveram diagnóstico de tuberculose e 55 com diagnóstico descartado. O sistema de pontuação proposto pelo Ministério da Saúde para o diagnóstico de tuberculose em crianças com baciloscopia negativa apresentou uma boa sensibilidade em ambos os grupos estudados, sendo o melhor ponto de corte o critério 1 (possível diagnóstico de tuberculose) com sensibilidade de 92% podendo, então, ser usado como um auxiliar na investigação diagnóstica de crianças que se submeterão ao lavado gástrico. Nossa recomendação é que o sistema de pontuação do Ministério da Saúde seja utilizado nos serviços de saúde para auxiliar o médico a decidir sobre continuar ou não a investigação da tuberculose infantil, e não somente em crianças que já foram submetidas ao procedimento e tiveram suas amostras com resultado negativo.<br>Tuberculosis is currently one of the main causes of death in the world. One of the difficulties for tuberculosis diagnosis in childhood is the bacteriological identification of Mycobacterium tuberculosis. This nested case-control study aimed to compare the diagnostic values of a scoring system proposed by the Brazilian Ministry of Heath for diagnosis of childhood tuberculosis using gastric washing samples taken in the outpatient and hospital settings. A total of 108 children underwent gastric washing (53 with and 55 without tuberculosis). The scoring system proposed by the Brazilian Ministry of Heath for diagnosis of tuberculosis in children with negative sputum smears showed good sensitivity in both groups, and the best cutoff point was "1" (possible tuberculosis), with 92% sensitivity, thus feasible for use as an ancillary diagnostic test in children submitted to gastric washing. Our recommendation is that the Ministry of Health scoring system be used by health services to assist the physician in deciding on whether to continue the investigation of childhood tuberculosis, and not only in children who have already undergone the procedure and who have shown negative results