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The blood-testis barrier (BTB) is responsible for providing a protected environment and coordinating the spermatogenesis. Endocrine disruptors (EDs) might lead to infertility, interfering in the BTB structure and modulation. This study aimed to correlate the actions of two EDs, monobutyl phthalate (MBP) and bisphenol A (BPA) in different periods of exposure, in a low toxicity dose to the human Sertoli cells (HSeC) and its effects on the proteins of the BTB and regulatory proteins involved in its modulation. HSeC cells were exposed to MBP (10 μM) and BPA (20 μM) for 6 and 48 h. Western Blot assay indicated that MBP was able to reduce the expression of occludin, ZO-1, N-cadherin and Androgen Receptor (AR), while BPA leads to a reduction of occludin, ZO-1, β-catenin and AR. TGF-β2 and F-actin were not modified. Phalloidin and Hematoxylin and Eosin assay revealed phenotically disruption in Sertoli cells adhesion, without changes in F-actin expression or localization. Our data suggested both EDs present potential for disrupting the structure and maintenance of the human BTB by AR dependent pathway. [ABSTRACT FROM AUTHOR]

Resumo Justificativa e objetivos O efeito profilático do ondansetron sobre prurido provocado pela morfina subaracnoidea é controverso, enquanto evidências sugerem que o droperidol previne o prurido. O objetivo do presente trabalho é comparar o efeito do droperidol com o do ondansetron sobre o prurido provocado pela morfina subaracnoidea. Métodos 180 pacientes ASA I ou II programadas para serem submetidas a cesarianas sob anestesia subaracnoidea à qual foram acrescentados 0,2 mg de morfina foram divididas aleatoriamente para receber, logo após o nascimento da criança, 10 mg de metoclopramida (grupo I – controle), 2,5 mg de droperidol (grupo II ),ou 8 mg de ondansetron (grupo III ). No período pós‐operatório as pacientes foram avaliadas quanto ao prurido (ausente, leve, moderado ou intenso) ou outros efeitos colaterais por observadores que não sabiam a alocação das pacientes. As pacientes também não sabiam da sua alocação. Os grupos foram comparados pela sua tendência a apresentar formas mais severas de prurido. Também determinamos o NNT. Resultados As pacientes alocadas para receber droperidol [ Odds Ratio Proporcional: 0,45 (Intervalo de Confiança de 95% 0,23 – 0,88)] relataram menos prurido do que as que receberam metoclopramida. O efeito do ondansetron foi semelhante ao da metoclopramida [ Odds Ratio Proporcional: 0,95 (Intervalo de Confiança de 95% 0,49 – 1,83)]. O NNT do droperidol foi 4,0 e o do ondansetron foi 14,7. Conclusões O ondansetron não inibiu o prurido provocado pela morfina subaracnoidea. Background and objectives The prophylactic effect of ondansetron on subarachnoid morphine‐induced pruritus is controversial, while evidence suggests that droperidol prevents pruritus. The aim of this study is to compare the effects of droperidol and ondansetron on subarachnoid morphine‐induced pruritus. Methods 180 ASA I or II patients scheduled to undergo cesarean sections under subarachnoid anesthesia combined with morphine 0.2 mg were randomized to receive, after the child's birth, metoclopramide 10 mg (Group I – control), droperidol 2.5 mg (Group II ) or ondansetron 8 mg (Group III ). Postoperatively, the patients were assessed for pruritus (absent, mild, moderate or severe) or other side effects by blinded investigators. Patients were also blinded to their group allocation. The tendency to present more severe forms of pruritus was compared between groups. NNT was also determined. Results Patients assigned to receive droperidol [Proportional odds ratio: 0.45 (95% confidence interval 0.23‐0.88)] reported less pruritus than those who received metoclopramide. Ondansetron effect was similar to metoclopramide [Proportional odds ratio: 0.95 (95% confidence interval 0.49‐1.83)]. The NNT for droperidol and ondansetron was 4.0 and 14.7, respectively. Conclusions Ondansetron does not inhibit subarachnoid morphine‐induced pruritus. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The incorporation of light-curable resins has been proposed for mineral trioxide aggregate (MTA) to improve its properties and reduce its setting time. The aim of the present study was to assess the pH and calcium ion release of an experimental bisphenol A ethoxylate dimethacrylate/MTA-based root-end filling material (E-MTA) in comparison with white MTA Angelus (Angelus, Londrina, PR, Brazil) (W-MTA) and to evaluate the influence of the addition of calcium chloride (CaCl2) on these properties. Methods: Polyethylene tubes filled with the materials were immersed in deionized water for the measurement of pH (digital pH meter) and calcium release (atomic absorption spectrophotometry). The evaluations were performed at 3 and 24 hours and 7, 15, and 30 days. Data were measured using 2-way repeated measures of variance followed by the Holm-Sidak method (P < .05). Results: All materials presented a reduction in the pH and released calcium ions during the 30 days of the study. E-MTA showed a significantly lower calcium ion release capacity when compared with W-MTA (P < .05). The calcium release of E-MTA + 5% CaCl2 was similar to W-MTA (P > .05). Conclusions: The monomer bisphenol A ethoxylate dimethacrylate added to MTA formed a material with a lower capacity of calcium release than W-MTA despite maintaining a similar pH. However, the addition of CaCl2 improved the calcium release of this material. [Copyright &y& Elsevier]

Abstract: Two procedures for the determination of Co in biological samples by graphite furnace atomic absorption spectrometry (GF AAS) were compared: solid sampling (SS) and alkaline treatment with tetramethylammonium hydroxide (TMAH) using two different instruments for the investigation: a conventional line-source (LS) atomic absorption spectrometer and a prototype high-resolution continuum source atomic absorption spectrometer. For the direct introduction of the solid samples, certified reference materials (CRM) were ground to a particle size ≤50 μm. Alkaline treatment was carried out by placing about 250 mg of the sample in polypropylene flasks, adding 2 mL of 25% m/v tetramethylammonium hydroxide and de-ionized water. Due to its unique capacity of providing a 3-D spectral plot, a high-resolution continuum source (HR-CS) graphite furnace atomic absorption spectrometry was used as a tool to evaluate potential spectral interferences, including background absorption for both sample introduction procedures, revealing that a continuous background preceded the atomic signal for pyrolysis temperatures lower than 700 °C. Molecular absorption bands with pronounced rotational fine structure appeared for atomization temperatures >1800 °C probably as a consequence of the formation of PO. After optimization had been carried out using high resolution continuum source atomic absorption spectrometry, the optimized conditions were adopted also for line-source atomic absorption spectrometry. Six biological certified reference materials were analyzed, with calibration against aqueous standards, resulting in agreement with the certified values (according to the t-test for a 95% confidence level) and in detection limits as low as 5 ng g−1. [Copyright &y& Elsevier]

Abstract: A method for the determination of Cd, Hg, Pb and Se in sediments reference materials by slurry sampling chemical vapor generation (CVG) using isotopic dilution (ID) calibration and detection by inductively coupled plasma mass spectrometry (ICP-MS) is proposed. Two different systems were used for the investigation: an on-line flow injection system (FI-CVG-ICP-MS) and an off-line system with in situ trapping electrothermal vaporization (CVG-ETV-ICP-MS). About 100 mg of the reference material, ground to a particle size ≤50 μm, was mixed with acid solutions (aqua regia, HF and HCl) in an ultrasonic bath. The enriched isotopes 111Cd, 198Hg, 206Pb and 77Se were then added to the slurry in an adequate amount in order to produce an altered isotopic ratio close to 1. For the on-line system, a standing time for the slurry of 12 h before measurement was required, while for the batch system, no standing time is needed to obtain accurate results. The conditions for the formation of the analyte vapor were optimized for the evaluated systems. The following altered isotope ratios were measured: 111Cd/114Cd, 198Hg/199Hg, 206Pb/208Pb e 77Se/82Se. The obtained detection limits in the on-line system, in μg g−1, were: Cd: 0.15; Hg: 0.09; Pb: 6.0 and Se: 0.03. Similar detection limits were obtained with the system that uses the ETV: 0.21 for Hg, 6.0 for Pb and 0.06 μg g−1 for Se. No signal for Cd was obtained in this system. One estuarine, two marine and two river certified sediments were analyzed to check the accuracy. The obtained values by both systems were generally in agreement with the certified concentrations, according to the t-test for a confidence level of 95%, demonstrating that isotope equilibration was attained in the slurries submitted to a chemical vapor generation procedure and detection by ICP-MS. The relative standard deviations were lower than 10%, adequate for slurry analysis. The almost quantitative analytes extractions to the aqueous phase of the slurry must favor equilibration of the added enriched isotope with the isotope in the sample, allowing the use of isotopic dilution calibration for slurry analysis. [Copyright &y& Elsevier]

A method for the determination of As, Hg, Sb, Se and Sn in environmental and in geological reference materials, as acidified slurries, by flow injection (FI) coupled to a hydride generation system (HG) and detection by inductively coupled plasma mass spectrometry (ICP-MS) is proposed. The HG unit has a gas liquid separator and a drying unit for the generated vapor. The slurries were prepared by two procedures. Approximately 50 mg of the reference material, ground to a particle size ≤50 μm, was mixed with acid solutions in an ultrasonic bath. In Procedure A, the medium was a hydrochloric acid solution while in Procedure B, the medium was aqua regia plus a hydrochloric acid solution. The conditions for the slurry formation and the instrumental parameters were optimized. Harsh conditions were used in the slurry preparation in order to reduce the hydride forming analytes to their lower oxidation states, As (III), Se(IV), Sb(III) and Sn(II), before reacting with sodium tetrahydroborate. To test the accuracy, 10 certified reference materials were analyzed (four sediments, three coals, one coal fly ash and two sewage sludges), with the analyte concentrations mostly in the μg g−1 level. Good agreements with the certified values were obtained for Hg, Sb and Sn in the sediments using Procedure A and calibration against aqueous standard solutions. Using Procedure B, good results were obtained for Hg, Se and Sn in the sediment samples, for Se in the coal and coal fly ash samples and for Hg in the sewage sludge samples, also using external calibration with aqueous standard solutions. For As in sediments, coals and coal fly ash, Procedure B and the analyte addition calibration was required, indicating matrix effects. The relative standard deviations were lower than 5%, demonstrating a good precision for slurry analysis. The limits of quantification (10 times the standard deviation; n=10), in the samples, in ng g−1, were: 20 for As, 60 for Hg, 80 for Sb, 200 for Se and 90 for Sn. The method requires small amounts of reagents and reduces contamination and losses. [Copyright &y& Elsevier]

A simple and reliable method for the determination of arsenic in sediment and in coal without sample digestion, based on hydride generation from slurry samples is proposed. After grinding the samples to a particle size of &les;50 μm, the sample powder was mixed with aqua regia and hydrofluoric acid in an ultrasonic bath for 30 min. After diluting the mixture with hydrochloric acid, the slurry was allowed to stand for 48 h, and an aliquot was used for hydride generation with sodium borohydride. More than 80% of the arsenic was leached to the aqueous phase under these conditions, except for one sediment sample with very high silica content. The generated arsine was collected in a graphite tube, treated with 0.5 mg of iridium as a permanent modifier, and the arsenic determination was carried out by electrothermal atomic absorption spectrometry. The same tube could be used for at least 160 cycles without any re-treatment. The greatest advantage of the method was that only a minimum of reagents and sample handling were required, reducing the risks of contamination and/or analyte loss. However, the addition calibration technique had to be used in order to obtain results within the 95% confidence level for 11 certified reference materials, 5 sediments, 5 coals and one coal fly ash. One certified sediment slurry was spiked with the analyte and the resulting addition calibration curve was used for the analysis of the certified sediments. Similarly, one certified coal was used to obtain the addition calibration curve for the coal and coal fly ash samples. The recoveries of the certified values, except for one sediment, were between 91 and 115%. The limits of detection in the samples were 0.54 and 0.7 μg g−1 for the coal and sediment samples, respectively, obtained for 1 ml of slurry containing 1 mg of sample. [Copyright &y& Elsevier]

The world's declining plant biodiversity depends on the efficacy of many policy tools, including Environmental Impact Assessment (EIA). While scholars have long been trying to understand how biodiversity information affects EIA decision-making, very few studies have addressed the specific challenges associated with threatened plant species. Based on content analysis of 83 EIA processes that proposed vegetation removals in the southeastern Brazilian state of Minas Gerais, this study evaluated the extent to which threatened plant species were considered in decision-making. The study found that the developers of 31 projects (37% of the 83 analyzed EIA projects) disclosed the occurrence of threatened plant species in the potentially affected areas. The detailed content analysis of their respective Environmental Impact Statement (EIS) review reports revealed that the majority of the identified impacts and respective compensation programs targeted tree habits, and under a variety of rationales. Developers' proposed compensation rates of impacted tree species varied from 1:1 to 50:1. The reviewing process reported issues related mostly to the baseline conditions. Overall, the study found that EIA, in Minas Gerais state, has been functioning mainly as a diagnostic and compensation tool for the removal of tree species. The study calls for improvements in existing legislation and the development of technical guidance and capacity-building programs for EIA stakeholders. • The extent to which threatened plant species are considered in EIA is unclear. • In the sample, developers tended to communicate impacts in connection with tree habits. • Identified compensation rates of removed tree species varied from 1:1 to 50:1. • EIA, in the study area, was essentially helping to identify and compensate impacts on tree species. [ABSTRACT FROM AUTHOR]

Bovine leukemia virus (BLV) is a major cause of lymphoma in cattle and has been recently correlated to breast cancer in humans. How and whether BLV might reach humans remains unknown but it could be through cattle-derived milk and meat. Here our aim was to investigate whether BLV DNA could be found in fresh milk and raw meat destined to human consumption and whether anti-BLV antibodies could be detected in human blood at the same geographical region. Milk (n = 36) and meat (n = 54) samples were collected from cows knowingly seropositive or negative to BLV and evaluated by nested PCR targeting BLV tax gene. Human serum samples (n = 900) were tested by ELISA to detect anti-BLV antibodies. BLV DNA was detected in 39 % of the milk samples and in 32 % of meat samples from BLV positive cows. Anti-BLV antibodies were found in 4.1 % of the human serum samples. Our data further supports the hypothesis that BLV might cause a zoonotic infection and indicate that milk and meat from BLV-infected cattle might be considered a potential source of infection to humans. • BLV is widely distributed in dairy cattle. • BLV DNA was found on cow's milk and meat. • Humans have antibodies to BLV. [ABSTRACT FROM AUTHOR]

Abstract: Five different slurry preparation procedures were tested, after grinding the solid samples to a particle size ≤53 μm: (1) using aqua regia plus HF, 30 min of sonication, standing time of 24 h followed by another 30 min of sonication; (2) same as the previous one, except that the standing time and the second ultrasound treatment were omitted; (3) same as the previous one, except that HF was not used; (4) same as the previous one, except that the aqua regia was replaced by nitric acid; (5) same as the previous one, except that the acid nitric was replaced by tetramethylammonium hydroxide (TMAH). The Hg vapor was generated on-line, and the emission signal intensity measured at 253.652 nm by axial view inductively coupled plasma optical emission spectrometry. Initially, four experimental conditions were optimized using a multivariate factorial analysis: the concentrations of HCl and of the reducing agent, NaBH4, used in the cold vapor generation, and two instrumental parameters, the plasma radiofrequency power and the carrier gas flow rate. The radiofrequency power was statistically significant, but limited to 1.2 kW for practical reasons. The procedures were applied to 11 biological and environmental materials. Both, the slurries and the filtrates were analyzed, using calibration solutions in the same medium as in the slurries. The first three procedures produced results in agreement with the certified values. The two last procedures, using nitric acid or TMHA could not be used for quantitative analysis. For practical reasons, Procedure 3, with a detection limit (3s, n=10) of 0.06 μg g−1 for a sample mass of 20 mg in a final volume of 15 mL is recommended. The relative standard deviations for mercury in the investigated materials, using the recommended procedure, were lower than 12.5%, indicating a good precision for slurry sampling. The recommended procedure is simple, rapid and robust. [Copyright &y& Elsevier]

The acid decomposition method was applied for the sample preparation of processed fruit juice. The decomposition of 15 mL of juice sample using HNO 3 and H 2 O 2 was performed in a digester block with reflux system and heated at 200 °C for 150 min. The limits of detection were 0.03; 0.24; 0.8; 0.008; 0.026 and 0.056 mg L −1 for Cr, Cu, K, Mg, Na and Zn, respectively and for Pb was 0.99 μg L −1 . The accuracy was evaluated by spiked experiments (80 to 119%). Four processed fruit juice samples commercialized in Brazil (strawberry, mango, peach, and orange) were analyzed and indicated the absence of Cr, Zn and Cu in the samples, except for Cu in strawberry juice. Pb was found in the mango juice sample (17.8 ± 0.9 μg L −1 ) and the concentration is below the maximum values recommended by Brazilian legislation for juices of citric fruits (0.3 mg kg −1 ). [ABSTRACT FROM AUTHOR]

• K was the macroelement with higher values for total concentration. • Al, B, Ba, Cu, Fe, Mn and Zn presented bioaccessible concentrations. • Mn presented the highest percentage of bioaccessible fraction (46–84%). • Bioacessible fractions of Al, B and Ba did not represent health risks. • Phenolic compounds showed a negative influence on the bioaccessible fractions of Al, B, Fe and Zn. This paper describes studies for the determination of total concentration and bioaccessible fraction of minerals in peaches by MIP OES. The PCA analysis identified 3 distinct groups of elements concerning the total concentration, which was attributed to the origin of each cultivar. Among the macroelements, K presented higher values for total concentration, while B and Fe predominated among the microelements. Regarding the bioaccessible fraction, Mn presented the highest percentage (46–84%), followed by Zn and B (10–63% and 33–57%, respectively). Pearson's correlation coefficient revealed that reducing sugars and titratable acidity can influence the mineral bioaccessibility, highlighting the strong positive correlations between reducing sugars with Mn and total acidity with Fe. Peach cultivars have satisfactory nutritional value, but the total and bioaccessible concentrations of minerals obtained do not meet the recommended daily needs, requiring the consumption of other fruits and vegetables to complement the diet. [ABSTRACT FROM AUTHOR]

The present work describes a sample preparation method using acid decomposition in reflux system for the determination of Hg on xanthan gum samples by cold vapor atomic absorption spectrometry (CV AAS). The best conditions of sample preparation method were optimized. This procedure proved to be safe for the quantification of this analyte, because no significant losses of Hg by volatilization, which is due to the efficient reflux system. The limits of detection and quantification were 0.0049 and 0.0163 μg g−1, respectively. The accuracy was evaluated through recovery tests performed with different species of Hg and CRM analysis, obtaining excellent recoveries. The values of Hg were below the LOD (m) for xanthan gum samples A and B. However, the other samples showed concentrations in the range of 0.027–0.325 μg g−1. The method proves suitable for the quantification of Hg, which is important due to the wide applicability of xanthan gum. [Display omitted] • Hg was determined in xanthan gum samples by CV AAS. • The samples were efficiently prepared using acid decomposition in reflux system. • Hg values found are below the established for tolerable daily intake in relation to body weight. [ABSTRACT FROM AUTHOR]