974 resultados para diethyl phthalate (DEP)


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The migration of diethylhexyl phthalate (DEHP) from PVC bags into LVPS (0.9% NaCl) and LVPS with cyclosporine at concentrations of 2.5 and 0.5 mg/ml was studied. PVC bags were placed in contact with these solutions and stored at 25 1 degrees C. They were taken for analysis each 30 min during 6 h and after this period at each 1 h until 12 h of contact. Water was used as reference, and exposed and analyzed under the same conditions. After contact, the solutions were submitted to extraction with hexane and analyzed by GC-FID. The results showed that DEHP did not migrate into water and LVPS during all the time. Also, no measurable amount of DEHP was detected during the first 3 h of contact between the PVC bag and the diluted cyclosporine solution. However, the amount of released DEHP reached a detectable level after 4 It of contact, increased until 6 h, stabilized, and increased again after 9-10 h. The 12 h of contact showed the highest DEHP levels for both cyclosporine concentrations. The DEHP migrated was 0.02-0.08% of that present in the bag. (c) 2005 Elsevier B.V. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The potential adverse reproductive effects, with emphasis on the epididymis, of in utero and lactational exposure to 100 mg/kg/d di-n-butyl phthalate (DBP) in adult male rat offspring were investigated. The fetal testis histopathology was also determined. The selected endpoints included reproductive organ weights, sperm motility and morphology, sperm epididymal transit time, sperm quantity in the testis and epididymis, hormonal status, fetal testis and epididymal histopathology and stereology, and androgen receptor (AR), aquaporin 9 (AQP9), and Ki-67 immunoreactivities. Pregnant females were divided into two groups: control (C) and treated (T). The treated females received DBP (100 mg/kg/d, by gavage) from gestation day (GD) 12 to postnatal day (PND) 21, while control dams received the vehicle. Some pregnant dams were killed by decapitation on GD20, and testes from male fetuses were collected for histopathogy. Male rats from other dams were killed at PND 90. Fetal testes from treated group showed Leydig-cell clusters, presence of multinucleated germinative cells, and increase of the interstitial component. Testosterone levels and reproductive organ weights were similar between the treated and control adult groups. DBP treatment did not markedly affect relative proportions of epithelial, stromal, or luminal compartments in the epididymis; sperm counts in the testis and epididymis; sperm transit time; or sperm morphology and motility in adult rats. The AR and AQP9 immunoreactivities and proliferation index were similar for the two groups. These results showed that fetal testes were affected by DBP as evidenced by testicular histopathologic alterations, but reproductive parameters and epididymal structure/function were not significantly altered in the adult animals exposed to 100 mg/kg DBP in utero and during lactation.

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Protetores ou safeners protegem culturas contra a injúria de herbicidas. O propósito deste estudo foi investigar a suscetibilidade diferencial de cinco variedades de trigo (Triticum aestivum) ao herbicida fenoxaprop-p-ethyl e o efeito do protetor mefenpyr-diethyl na minimização da injúria do herbicida e sobre o conteúdo de lipídios. As variedades BRS 49, CD 104, CEP 24, IAPAR 78 e Rubi foram pulverizadas com fenoxaprop-p-ethyl (69 g ha-1), fenoxaprop-p-ethyl + mefenpyr‑diethyl (69 g + 18,75 g ha¹) ou mefenpyr-diethyl (18,75 g ha¹). A injúria das plantas foi avaliada visualmente aos 7 e 14 dias após o tratamento (DAT). A atividade da glutationa S-transferase (GST) foi analisada na parte aérea aos 7 DAT, e o conteúdo de lipídios, aos 14 DAT. As variedades CEP 24, IAPAR 78 e Rubi foram mais tolerantes ao fenoxaprop-p-ethyl do que a BRS 49, e a variedade CD 104 rapidamente se recuperou dos sintomas de intoxicação produzidos pelo herbicida. Mefenpyr-diethyl preveniu a injúria da cultura pelo herbicida. A atividade da GST não foi correlacionada diretamente com a desintoxicação do fenoxaprop-p-ethyl. Contudo, o conteúdo de lipídios esteve relacionado à suscetibilidade de trigo ao tratamento de fenoxaprop-p-ethyl.

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Deposits formed on the surface of. paper were analysed in order to identify the sources of the defects, as well as to solve the problems associated with performance and adjustments at the wet end of the paper forming process. Standard paper samples containing deposits were collected and analysed by comparing the microstructure and composition of the deposit with paper regions adjacent to it. Optical microscopy (OM). energy dispersive X-ray microanalysis (EDX) X-ray powder diffraction (XRD). thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were the techniques used in this study. The results obtained from the EDX, XRD. and TG techniques allowed concluding that the calcium carbonate content in the farm of calcite is 1.6 times higher in the formed deposit them the quantity expected in the standard paper composition. The paper sample microstructure revealed by the SEM images indicates the presence of irregular spherical aggregates up to 20μm in diameter in the deposit region. containing larger amount of calcium carbonate as well as in the regions adjacent to the deposit. These spherical aggregates seem to be absorbed and integrated into the pulp fibres and present characteristics similar to those of partially cooked cationic starch. The analysed deposits are characterised by a dense and thick substance, forming a plate with highly adhesive property. This adhesive substance has a characteristic similar to glue with a large amount of organic matter due to the high weight loss shown by the TG curve. The results are consistent with the interaction ofparticles of negatively charged calcium carbonate and cationic starch, forming sterically stabilized deposits, which firmly adhere to the paper microstructure.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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In the present study, it was evaluated the susceptibility of prostatic lesions in male adult rats exposed to Di-N-butyl-phthalate during fetal and lactational periods and submitted to MNU plus testosterone carcinogenesis protocol. Pregnant females were distributed into four experimental groups: CN (negative control); CMNU (MNU control); TDBP100 (100 mg/kg of DBP); TDBP500 (500 mg/kg of DBP). Females from the TDBP groups received DBP, by gavage, from gestation day 15 (GD15) to postnatal day 21 (DPN21), while C animals received the vehicle (corn oil). CMNU, TDBP100, and TDBP500 groups received a single intraperitoneal injection of MNU (50 mg/kg) on the sixth postnatal week. After that, testosterone cypionate was administered subcutaneously two times a week (2 mg/kg) for 24 weeks. The animals were euthanized on PND220. Distal segment fragments of the ventral (VP) and dorsolateral prostate (DLP) were fixed and processed for histopathological analysis. Protein extracts from ventral prostate were obtained, and western blotting was performed to AR, ERα, MAPK (ERK1/2), and pan-AKT. Stereological analysis showed an increase in the epithelial compartment in TDBP100 and TDBP500 compared to CN. In general, there was increase in the incidence of inflammation and metaplasia/dysplasia in the DBP-treated groups, mainly in DLP, compared to CN and CMNU. Proliferation index was significant higher in TDBP500 and PIN (prostatic intraepithelial neoplasia) was more frequent in this group compared to CMNU. Western blot assays showed an increase in the expressions of AR and MAPK (ERK1/2) in the TDBP100 compared to CN, and ERα and AKT expressions were higher in the TDBP500 group compared do CN. These results showed that different doses of DBP during prostate organogenesis in Wistar rats could increase the incidence of premalignant lesions in initiated rats inducing distinct biological responses in the adulthood. © 2015 Wiley Periodicals, Inc. Environ Toxicol, 2015.

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Nowadays the medical field is struggling to decrease bacteria biofilm formation which leads to infection. Biomedical devices sterilization has not changed over a long period of time. This results in high costs for hospitals healthcare managements. The objective of this project is to investigate electric field effects and surface energy manipulation as solutions for preventing bacteria biofilm for future devices. Based on electrokinectic environments 2 different methods were tested: feasibility of electric gradient through mediums (DEP) reinforced by numerical simulations; and EWOD by the fabrication of golden interdigitated electrodes on silicon glass substrates, standard ~480 nm Teflon (PTFE) layer and polymeric gasket to contain the bacteria medium. In the first experiment quantitative analysis was carried out to achieve forces required to reject bacteria without considering dielectric environment limitations as bacteria and medium frequency dependence. In the second experiment applied voltages was characterized by droplets contact angle measurements and put to the live bacteria tests. The project resulted on promising results for DEP application due to its wide range of frequency that can be used to make a “general” bacteria rejecting; but in terms of practicality, EWOD probably have higher potential for success but more experiments are needed to verify if can prevent biofilm adhesion besides the Teflon non-adhesive properties (including limitations as Teflon breakthrough, layer sensitivity) at incubation times larger than 24 hours.

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Benzodifuran-functionalised pyrene and anthracene fluorophores 1 and 2 were obtained in reasonable yields. Their single crystal structures, electrochemical, optical absorption, and fluorescence characteristics have been described. They show strong luminescence with high quantum yields of 0.53 for 1 and 0.48 for 2. Magnetic measurements for the 2D coordination polymer [Mn(Pht(Pyz(H2O)2]n (1), in which metal centres are linked together by pyrazine (Pyz) and 1,6-bridging o-phthalate ligand (Pht2-), revealed antiferromagnetic interactions between Mn(II) ions.

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New coordination polymers [M(Pht)(4-MeIm)2(H2O)]n (M=Co (1), Cu (2); Pht2−=dianion of o-phthalic acid; 4-MeIm=4-methylimidazole) have been synthesized and characterized by IR spectroscopy, X-ray crystallography, thermogravimetric analysis and magnetic measurements. The crystal structures of 1 and 2 are isostructural and consist of [M(4-MeIm)2(H2O)] building units linked in infinite 1D helical chains by 1,6-bridging phthalate ions which also act as chelating ligands through two O atoms from one carboxylate group in the case of 1. In complex 1, each Co(II) atom adopts a distorted octahedral N2O4 geometry being coordinated by two N atoms from two 4-MeIm, three O atoms of two phthalate residues and one O atom of a water molecule, whereas the square-pyramidal N2O3 coordination of the Cu(II) atom in 2 includes two N atoms of N-containing ligands, two O atoms of two carboxylate groups from different Pht, and a water molecule. An additional strong O–H⋯O hydrogen bond between a carboxylate group of the phthalate ligand and a coordinated water molecule join the 1D helical chains to form a 2D network in both compounds. The thermal dependences of the magnetic susceptibilities of the polymeric helical Co(II) chain compound 1 were simulated within the temperature range 20–300 K as a single ion case, whereas for the Cu(II) compound 2, the simulations between 25 and 300 K, were made for a linear chain using the Bonner–Fisher approximation. Modelling the experimental data of compound 1 with MAGPACK resulted in: g=2.6, |D|=62 cm−1. Calculations using the Bonner–Fisher approximation gave the following result for compound 2: g=2.18, J=–0.4 cm−1.