Using the Pneumatic method to estimate embolism resistance in species with long vessels: A commentary on the article “A comparison of five methods to assess embolism resistance in trees”

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordComparisons among methods are essential to validate plant traits measured across studies. However, a rigorous analysis is a complex task that needs to take into account not only the principle of the method and its correct use, but also inherent intraspecific trait variability, something we feel is not fully considered by Sergent et al. (2020). They compared the Bench dehydration, MicroCT, and Pneumatic methods using three long-vesseled species and found divergence among these methods. As a key finding, Sergent and colleagues reported unreliable estimates of Ψ50 for Olea europaea when using the Pneumatic method in a such long-vesseled species. Here, we tested this finding by measuring independently vulnerability curves for O. europaea. Our results reinforce the viability of the Pneumatic method to estimate embolism vulnerability in long-vesseled species, as already found by others. Briefly, we also discuss important procedures when using the Pneumatic method and encourage further experiments, as the only way to know better the limitations of available methods and improve our understanding about plant water relations.São Paulo Research Foundation (FAPESP)Royal SocietyNational Council for Scientific and Technological Development (CNPq, Brazil

Dietary supplementation with hydrolyzed yeast and its effect on the performance, intestinal microbiota, and immune response of weaned piglets.

The objective of this study was to evaluate the effects of autolyzed yeast on performance, cecal microbiota, and leukogram of weaned piglets. A total of 96 piglets of commercial line weaned at 21-day-old were used. The experimental design was a randomized block design with four treatments (diets containing 0.0%, 0.3%, 0.6%, and 0.9% autolyzed yeast), eight replicates, and three animals per pen in order to evaluate daily weight gain, daily feed intake, and feed conversion in periods of 0 to 15, 0 to 26, and 0 to 36 days. Quadratic effects of autolyzed yeast inclusion were observed on the feed conversion from 0 to 15 days, on daily weight gain from 0 to 15 days, 0 to 26 days and, 0 to 36 days, indicating an autolyzed yeast optimal inclusion level between 0.4% and 0.5%. No effect from autolyzed yeast addition was observed on piglet daily feed intake, cecal microbiota, and leukogram; however, i.m. application of E. coli lipopolysaccharide reduced the values of total leukocytes and their fractions (neutrophils, eosinophils, lymphocytes, monocytes, and rods). Therefore, autolyzed yeast when provided at levels between 0.4% and 0.5% improved weaned piglets’ performance.info:eu-repo/semantics/publishedVersio

The Pneumatron: An automated pneumatic apparatus for estimating xylem vulnerability to embolism at high temporal resolution

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordXylem vulnerability to embolism represents an important trait to determine species distribution patterns and drought resistance. However, estimating embolism resistance frequently requires time-consuming and ambiguous hydraulic lab measurements. Based on a recently developed pneumatic method, we present and test the “Pneumatron”, a device that generates high time-resolution and fully automated vulnerability curves. Embolism resistance is estimated by applying a partial vacuum to extract air from an excised xylem sample, while monitoring the pressure change over time. Although the amount of gas extracted is strongly correlated with the percentage loss of xylem conductivity, validation of the Pneumatron was performed by comparison with the optical method for Eucalyptus camaldulensis leaves. The Pneumatron improved the precision of the pneumatic method considerably, facilitating the detection of small differences in the (percentage of air discharged [PAD] < 0.47%). Hence, the Pneumatron can directly measure the 50% PAD without any fitting of vulnerability curves. PAD and embolism frequency based on the optical method were strongly correlated (r2 = 0.93) for E. camaldulensis. By providing an open source platform, the Pneumatron represents an easy, low-cost, and powerful tool for field measurements, which can significantly improve our understanding of plant–water relations and the mechanisms behind embolism.Natural Environment Research Council (NERC)Royal SocietyNational Council for Scientific and Technological Development (CNPq, Brazil)São Paulo Research Foundation (FAPESP, Brazil

IFN-γ Production to Leishmania Antigen Supplements the Leishmania Skin Test in Identifying Exposure to L. braziliensis Infection

Background Cutaneous leishmaniasis due to L. braziliensis (CL) is characterized by a positive delayed type hypersensitivity test (DTH) leishmania skin test (LST) and high IFN-γ production to soluble leishmania antigen (SLA). The LST is used for diagnosis of CL and for identification of individuals exposed to leishmania infection but without disease. The main aim of the present study was to identify markers of exposure to L. braziliensis infection. Methodolgy/Principal Findings This cohort study enrolled 308 household contacts (HC) of 76 CL index cases. HC had no active or past history of leishmaniasis. For the present cross-sectional study cytokines and chemokines were determined in supernatants of whole blood culture stimulated with SLA. Of the 308 HC, 36 (11.7%) had a positive LST but in these IFN-γ was only detected in 22 (61.1%). Moreover of the 40 HC with evidence of IFN-γ production only 22 (55%) had a positive LST. A total of 54 (17.5%) of 308 HC had specific immune response to SLA. Only a moderate agreement (Kappa = 0.52; 95% CI: 0.36–0.66) was found between LST and IFN-γ production. Moreover while enhancement of CXCL10 in cultures stimulated with SLA was observed in HC with DTH+ and IFN-γ+ and in patients with IFN-γ+ and DTH−, no enhancement of this chemokine was observed in supernatants of cells of HC with DTH+ and IFN-γ−. Conclusions/Significance This study shows that in addition of LST, the evaluation of antigen specific IFN-γ production should be performed to determine evidence of exposure to leishmania infection. Moreover it suggests that in some HC production of IFN-γ and CXCL10 are performed by cells not involved with DTH reaction

Acidentes de trabalho no Brasil entre 1994 e 2004: uma revisão Work-related accidents in Brazil from 1994 to 2004: an overview

Neste estudo sintetizam-se achados epidemiológicos sobre acidentes de trabalho fatais e não-fatais para populações brasileiras, entre 1994 e 2004, período pós II Conferência Nacional de Saúde do Trabalhador. Os estudos foram identificados em pesquisa nas bases Scielo e Medline, limitando-se a trabalhos completos disponíveis. Verificou-se que embora o coeficiente de mortalidade por acidentes de trabalho seja elevado, entre 1990 e 2003 caiu 56,5%. Todavia, a letalidade aumentou (0,18% em 1970 para 1,07%) até 1999, quando passou a declinar (0,70% em 2003). A incidência cumulativa anual de acidentes de trabalho não-fatais também vem reduzindo, mas discretamente, em especial, para os menos graves. Não houve alteração para os acidentes incapacitantes. Pesquisas populacionais mostram que a incidência cumulativa anual varia entre 3% e 6%. Trabalhadores rurais têm o dobro do risco do que os de área urbana. A construção civil, indústria da celulose, serviços domésticos estão entre os grupos de maior risco para acidentes não-fatais. A subnotificação de óbitos se concentrou entre 70% e 90%. Indica-se a necessidade de uma redefinição das políticas de proteção ao trabalhador tomando como base o conhecimento produzido sobre este evitável problema de saúde.<br>This study summarizes epidemiological findings about fatal and nonfatal occupational accidents in Brazilian populations, from 1994 to 2004, period after the 2nd National Conference of Workers’ Health. The studies were identified in the Scielo and Medline, limited to full-text publications. The occupational accidents mortality is high, but from 1990 to 2003 it decreased 56.5%. However, the letality elevated from 0.18% in 1970 to 1.07% in 1999, when started to decline (0.70% in 2003). The annual cumulative incidence of nonfatal work-related accidents, CI, is also decreasing in this period, although less dramatically, particularly for those of minor severity. No temporal changes were observed for disabling occupational accidents. Community-based studies show that the CI varies from 3% to 6%. Rural workers have twice the estimated risk for those living in urban areas. Construction, paper industry, and housemaids were at increased risk for nonfatal occupational accidents. The authors pointed to the need to redefine the current policies that address workers’ protection, using the knowledge accumulated about this preventable health problem