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The water supply for human consumption in the Chaco-Pampean region in Argentina is restricted by the low quality of groundwater due to elevated concentrations of arsenic and other trace elements. Previous studies indicated a complex concurrence of factors and processes that are believed responsible to control the distribution of arsenic in groundwater. For a better understanding of the origin of trace elements in the Pampean aquifer, flow-through experiments with loess and calcrete samples representative of the sediments that constitute the aquifer were carried out in continuous flow reactors. The aqueous solutions were collected and the concentrations of SiO2(aq), Ca2+, SO42-, Na+, Cl-, F- and trace elements (Ba, Sr, V, and As) were measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES), high performance liquid chromatography (HPLC) and capillary electrophoresis. The experiments showed differences in the release rate of elements to the solution according to the type of sediment. The highest concentrations of V, Ba, and As were measured in experiments conducted with loess, and these elements were released quickly to the solution in the first minute of the test. In the case of loess, V and As are suggested to be adsorbed on the solid particles surface. Conversely, the experiments conducted with calcrete showed a lower but continuous release of those elements. This last result may indicate that the trace elements were coprecipitated in the calcite. In addition, it was demonstrated that F did not come from the dissolution of minerals such as fluorapatite, but both desorption from solid surface and dissolution from calcite minerals account for the release of F. This study support that both dissolution and adsorption-desorption processes can control the mobility of trace elements, with an emphasis on the role of calcrete in the retention and the mobilization of trace elements in the Pampean aquifer.

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Aquaculture is anticipated to be a critical element in future solutions to global food shortage. However, diseases can impede industry efficiency and sustainability. Consequently, diseases can and have led to dramatic re-structuring in industry or regulatory practices. The emergence of infectious salmon anemia (ISA) in Chile is one such example. As in other countries, many mitigations were instituted universally, and many incurred considerable costs as they introduced a new layer of coordination of farming activities of marine sites within common geographic areas (termed 'neighborhoods' or 'barrios'). The aggregate response led to a strong reduction in ISA incidence and impact. However, the relative value of individual mitigations is less clear, especially where response policies were universally applied and retrospective analyses are missing 'controls' (i.e., areas where a mitigation was not applied). Further, re-focusing policies around disease prevention following resolution of an outbreak is important to renew sustainable production; though, again, field data to guide this shift in purpose are often lacking. Expert panels can offer timely decision support in the absence of empirical data. We convened a panel of fish health experts to weight risk factors predictive of ISA virus (ISAV) introduction or spread between Atlantic salmon barrios in Chile. Barrios, rather than sites, were the unit of interest because many of the new mitigations operate at this level and few available studies examine their efficacy. Panelists identified barrio processing plant biosecurity, fallowing strategies, adult live fish transfers, fish and site density, smolt quality, hydrographic connection with other neighborhoods, presence of sea lice (Caligus rogercresseyi), and harvest vessel biosecurity as factors with the greatest predictive strength for ISAV virulent genotype ('HPR-deleted') occurrence. Fewer factors were considered predictive of ISAV HPR0 genotype ('HPR0') occurrence, with greatest strengths assigned to fish and site density, adult live fish transfers, and smolt facility HPR0 status. Field validation based on ISAV and risk factor occurrence after panel completion generally supports expert estimates, and highlights a few factors (e.g., broodstock HPR0 status) less conclusive in the original study. Results inform legislation, industry best management practices and surveillance design.

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In 2006 a report on the analysis for lead in 80 new residential paints from four countries in Asia revealed high levels in three of the countries (China, India and Malaysia) and low levels in a fourth country (Singapore) where a lead in paint regulation was enforced. The authors warned of the possible export of lead-painted consumer products to the United States and other countries and the dangers the lead paint represented to children in the countries where it was available for purchase. The need for a worldwide ban on the use of lead in paints was emphasized to prevent an increase in exposure and disease from this very preventable environmental source. Since the earlier paper almost 300 additional new paint samples have been collected from the four initial countries plus 8 additional countries, three from Asia, three from Africa and two from South America. During the intervening time period two million toys and other items imported into the United States were recalled because the lead content exceeded the United States standard. High lead paints were detected in all 12 countries. The average lead concentration by country ranged from 6988 (Singapore) to 31,960ppm (Ecuador). One multinational company sold high lead paint in one country through January 2007 but sold low lead paint later in 2007 indicating that a major change to cease adding lead to their paints had occurred. However, the finding that almost one-third of the samples would meet the new United States standard for new paint of 90ppm, suggests that the technology is already available in at least 11 of the 12 countries to produce low lead enamel paints for domestic use. The need remains urgent to establish effective worldwide controls to prevent the needless poisoning of millions of children from this preventable exposure.

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Ethylene, used as a stimulant of latex production in Hevea brasiliensis, significantly activates the regenerating metabolism within the laticiferous cells. In this context, attention was focused on glutamine synthetase (GS; EC 6.3.1.2), a key enzyme in nitrogen metabolism. A specific and significant activation of the cytosolic glutamine synthetase (GScyt) in the laticiferous cells after ethylene treatment parallels the increase of latex yield. A marked accumulation of the corresponding mRNA was found, but in contrast, a slight and variable increase of the polypeptide level is at the limit of detection by western blotting. The GS response to ethylene might be mediated by ammonia that increases in latex cytosol following ethylene treatment. The physiological significance for such a regulation by ethylene of the GScyt is discussed in terms of the nitrogen requirement for protein synthesis associated with latex regeneration.

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A primeira ressecçäo para carcinoma do esôfago em humanos foi feita por Czerni em 1877 para um tumor da regiäo cervical e näo foi feita a reconstruçäo. Frank Rorek em 1913 foi o primeiro a realizar com sucesso uma esofagectomia de um tumor do terço médio, restabelecendo a continuidade através de um tubo de borracha. A incidencia varia entre 1.6 para 100.000 mulheres brancas norte-americanas até 19.5 para cada 100.000 negros. A maior incidencia é entre os Iranianos, Chineses, Russos e Sul do Brasil. Carcinoma do esôfago é 97% das vezes de variedade epidermóide e grosseiramente é classificado como protuberante, ulcerativo ou intramural. A doença se dissemina através dos linfáticos da submucosa e extraesofageano com metastatizaçäo precoce. A disfagia e perda de peso significa câncer do esôfago, até prova em contrário. O exame radiológico e a endoscopia fazem o diagnóstico em quase 100% dos casos. O tratamento é paliativo em 80-85% das vezes, levando em conta o restabelecimento da deglutiçäo e eliminaçäo da aspiraçäo, da fome e produzindo o menor trauma possível. Os cuidados pré operatórios incluem uma dieta alta em calorias, vitaminas e proteinas para os pacientes que podem se alimentar e se impossível, atraves de nutriçäo parenteral total. Deve ser feita sempre uma tentativa de retirada total do órgäo e substituí-lo seja com o estômago ou intestino grosso. A anastomose deve preferencialmente ser realizada no pescoço. A mortalidade operatória varia entre 6 e 25% ou mais. A sobrevida em cinco anos é em torno de 5-30%

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Descreve-se o caso de uma paciente de 34 anos de idade que, após ingestäo de soda cáustica, apresentou estenose do esôfago torácico e antro gástrico. Após dilataçäo instrumental desenvolveu perfuraçäo esofageana a qual foi tratada por esofagostomia cervical, drenagem pleural fechada bilateral, cerclagem da junçäo esofagogástrica e gastrostomia. Em tempos sucessivos foi submetida a coloplastia direita, que falhou, ressecçäo do antro gástrico com anastomose tipo Bilroth I, ressecçäo do jejuno e anastomose término-terminal. Em seguida, foi tentada a esofagogastroplastia com o tubo gástrico invertido, que também foi um insucesso, em virtude da exigüidade do tamanho do estômago remanescente pós-gastrectomia. Em seguida, foi realizada uma coloplastia esquerda, que redundou no pós-operatório imediato em insuficiência de múltiplos órgäos e fístula cervical. Após cuidados intensivos e suporte dos órgäos vitais, foi possível a recuperaçäo completa da paciente, que, 10 meses depois, se alimenta normalmente e está assintomática

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