991 resultados para 4-5 µm


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O aumento do uso de agrotóxicos no Brasil tem causado muitas preocupações, tanto em relação à questão ambiental quanto a saúde pública. Muitos desses compostos não são eficientemente removidos das águas por tratamento convencional, sendo necessárias alternativas que os removam das águas de abastecimento. Dentre as tecnologias existentes, a adsorção em CAP é considerada uma das mais efetivas e confiáveis, cujas vantagens incluem alta eficiência de remoção e facilidade de operação. O objetivo desta pesquisa é avaliar a remoção, em escala piloto, do agrotóxico 2,4-D e o seu principal metabólito 2,4-DCP em amostras de águas tratadas por adsorção em CAP associado ao tratamento convencional. Os testes foram realizados em instalação piloto na áreada ETA Carapina/CESAN. A água bruta foi a proveniente do rio Santa Maria da Vitória contaminadaatravés da adição de agrotóxico em sua fórmula comercial. Foram realizados quatro ensaios, dois sem adição de CAP e dois com adição de CAP junto à unidade de mistura rápida. Os agrotóxicos foram detectados e quantificados através da cromatografia líquida de alta eficiência, em metodologia validada. As amostras coletadas foram caracterizadas de acordo com os parâmetros: temperatura, turbidez, condutividade elétrica, absorbância em 254 nm, cor real, cor aparente, alcalinidade, carbono orgânico total, além e concentração dos agrotóxicos 2,4-D e ácido 2,4,5-T e do metabólito 2,4-DCP. Os diferentes ensaios foram avaliados em termos da taxa de remoção destes parâmetros. Como resultado no TCVcom adição de CAP o composto de interesse foi removido abaixo de 30 μg. L-1,Valor Máximo Permitido, estabelecido pela Portaria do MS n° 2.914/2011 para dosagem de 100μg.L-1e mostrou-se eficiente, também, na remoção de matéria orgânica. Em nenhum dos testes foi detectado o composto 2,4-DCP e 2,4,5-T.

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The new potentially N-4-multidentate pyridyl-functionalized scorpionates 4-((tris-2,2,2-(pyrazol-1-ypethoxy)methyl)pyridine (TpmPy, (1)) and 4-((tris-2,2,2-(3-phenylpyrazol-1-yl)ethoxy)methyl)pyridine (TpmPy(Ph), (2)) have been synthesized and their coordination behavior toward Fe-II, Ni-II, Zn-II, Cu-II, Pd-II, and V-III centers has been studied. Reaction of (1) with Fe(BF4)(2)center dot 6H(2)O yields [Fe(TpmPy)(2)](BF4)(2) (3), that, in the solid state, shows the sandwich structure with trihapto ligand coordination via the pyrazolyl arms, and is completely low spin (LS) until 400 K. Reactions of 2 equiv of (1) or (2) with Zn-II or Ni-II chlorides give the corresponding metal complexes with general formula [MCl2(TpmPy*)(2)] (M = Zn, Ni; TpmPy* = TpmPy, TpmPy(Ph)) (4-7) where the ligand is able to coordinate through either the pyrazolyl rings (in case of [Ni(TpmPy)(2)Cl-2 (5)) or the pyridyl-side (for [ZnCl2(TpmPy)(2)] (4), [ZnCl2(TpmPy(Ph))(2)] (6) and [NiCl2(TpmPy(Ph))(2)] (7)). The reaction of (1) with VCl3 gives [VOCl2(TpmPy)] (8) that shows the N-3-pyrazolyl coordination-mode. Moreover, (1) and react with cis-[PdCl2(CH3CN)(2)] to give the disubstituted complexes [PdCl2(TprnPy)(2)] (9) and [PdCl2(TpmPy(Ph))(2)] (10), respectively, bearing the scorpionate coordinated via the pyridyl group. Compounds (9) and (10) react with Fe(BF4)(2) to give the heterobimetallic Pd/Fe systems [PdCl2(mu-TpmPy)(2)-Fe](BF4)(2) (11) and [PdCl2(mu-TpmPy(Ph))(2)Fe-2(H2O)(6)]BF4)(4) (13), respectively. Compound (11) can also be formed from reaction of (3) with cis-[PdCl2(CH3CN)(2)], while reaction of (3) with Cu(NO3)(2).2.5H(2)O generates [Fe(mu-TpmPy)(2)-Cu(NO3)(2)](BF4)(2) (12), confirming the multidentate ability of the new chelating ligands. The X-ray diffraction analyses of compounds (1), (3), (4), (5), and (9) are also reported.

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We present a new model of the lepton sector that uses a family symmetry A(4) to make predictions for lepton mixing which are invariant under any permutation of the three flavours. We show that those predictions broadly agree with the experimental data, leading to a largish sin(2)theta(12) greater than or similar to 0.34, to vertical bar cos delta vertical bar greater than or similar to 0.7, and to vertical bar 0.5 - sin(2)theta(23)vertical bar greater than or similar to 0.08; cos delta and 0.5 - sin(2)theta(23) are predicted to have identical signs. (C) 2013 Elsevier B.V. All rights reserved.

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Dissertação de mestrado em Educação Especial (área de especialização em Dificuldades de Aprendizagem Específicas)

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In order to study the action of herbicides - sodium salt, amine salt and ester of 2,4-D, TCA and 2,4,5-T a preliminary experiment for pre-emergence weed control was corried out, and the corresponding results are given in table I and II. The corn used in the experiments was of the flint type 1A 3531. The loam soil on which the experiment has been carried out is called "terra roxa". All treatments were highly significant when compared with the check plots, except the 2B one in the control of broad leaf weeds, and 4B in the control of grass weeds. Among these treatments there are no significant differences. But we note the following: (table I). a) treatments of higher concentrations were superior to lower ones. b) the treatments which gave the best control for broad leaf weeds were in the following decreasing order: 1A, 5A and 3A. For grass weeds, they were 5A, 1A and 3A. c) the amine 2,4-D (600 grs. per hectare) supplied very good control when we get into consideration that on the acid basis, it was in very low concentration. d) TCA in high concentration affected the germination, growth and yield, in the lower one it did not show good control of weeds, especially of grasses. It is not suitable for pre-emergence control in corn. e) 2,4,5-T was not better than the 2,4-D products. As it is much more expensive than the others, economically its use in pre-emergence weed control in corn is not praticable. f) all the products used controled grass weeds as well as broad leaf ones; this show the superiority of the pre-emergence treatment method over that of post-emergence. g) Even a dose as strong as the treatment 1A (3.400g. of 2,4-D acid per hectare) did not damage corn production (table II). h) the superiority noted in the production of all the treatments with the exception of 2A, which damaged the plants, we atribute to the lack of competion between corn and weeds; all chek-plots suffered this competition, because they were not Probably, there was, also, hormonial effect of 2,4-D on the corn plant. Not withstanding the fact that the present experiment has been successful, we think that new researches are necessary, especially with the purpose of studying factors as climate and soil which in other countries, interferred with the success of the pre-emergence weed control.

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Cytotoxicity assays of 24 new 3,5-disubstituted-tetrahydro-2H-1,3,5-thiadiazin-2-thione derivatives were performed. The 17 compounds with higher anti-epimastigote activity and lower cytotoxicity were, thereafter, screened against amastigote of Trypanosoma cruzi. Out of these 17 derivatives S-2d was selected to be assayed in vivo, because of its remarkable trypanocidal properties. To determine toxicity against J774 macrophages, a method based on quantification of cell damage, after 24 h, was used. Cell respiration, an indicator of cell viability, was assessed by the reduction of MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] to formazan. Anti-amastigote activity was estimated after 48 h by microscopic counts of May Grünwald-Giemsa-stained monolayers. Nifurtimox and benznidazole were used as reference drugs. For the in vivo experiences, mice were infected with 10(4) blood trypomastigotes and then treated during 15 days with S-2d or nifurtimox by oral route. All of the compounds were highly toxic at 100 µg/ml for macrophages and a few of them maintained this cytotoxicity even at 10 µg/ml. Of the derivatives assayed against amastigotes 3k and S-2d showed an interesting activity, that was held even at 1µg/ml. It is demonstrated that the high anti-epimastigote activity previously reported is mainly due to the non-specific toxicity of these compounds. In vivo assays assessed a reduction of parasitemia after administration of S-2d to infected mice.

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A series of ring substituted 3-phenyl-1-(1,4-di-N-oxide quinoxalin-2-yl)-2-propen-1-one derivatives were synthesized and tested for in vitro leishmanicidal activity against amastigotes of Leishmania amazonensis in axenical cultures and murine infected macrophages. Structure-activity relationships demonstrated the importance of a radical methoxy at position R3', R4' and R5'. (2E)-3-(3,4,5-trimethoxy-phenyl)-1-(3,6,7-trimethyl-1,4-dioxy-quinoxalin-2-yl)-propenone was the most active. Cytotoxicity on macrophages revealed that this product was almost six times more active than toxic.

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BACKGROUND This study assesses the validity and reliability of the Spanish version of DN4 questionnaire as a tool for differential diagnosis of pain syndromes associated to a neuropathic (NP) or somatic component (non-neuropathic pain, NNP). METHODS A study was conducted consisting of two phases: cultural adaptation into the Spanish language by means of conceptual equivalence, including forward and backward translations in duplicate and cognitive debriefing, and testing of psychometric properties in patients with NP (peripheral, central and mixed) and NNP. The analysis of psychometric properties included reliability (internal consistency, inter-rater agreement and test-retest reliability) and validity (ROC curve analysis, agreement with the reference diagnosis and determination of sensitivity, specificity, and positive and negative predictive values in different subsamples according to type of NP). RESULTS A sample of 164 subjects (99 women, 60.4%; age: 60.4 +/- 16.0 years), 94 (57.3%) with NP (36 with peripheral, 32 with central, and 26 with mixed pain) and 70 with NNP was enrolled. The questionnaire was reliable [Cronbach's alpha coefficient: 0.71, inter-rater agreement coefficient: 0.80 (0.71-0.89), and test-retest intra-class correlation coefficient: 0.95 (0.92-0.97)] and valid for a cut-off value > or = 4 points, which was the best value to discriminate between NP and NNP subjects. DISCUSSION This study, representing the first validation of the DN4 questionnaire into another language different than the original, not only supported its high discriminatory value for identification of neuropathic pain, but also provided supplemental psychometric validation (i.e. test-retest reliability, influence of educational level and pain intensity) and showed its validity in mixed pain syndromes.

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BACKGROUND: Laser photocoagulation and cryotherapy to completely destroy telangiectatic vessels and ischemic retina in Coats disease is barely applicable in advanced cases with total retinal detachment, and globe survival is notoriously poor in Stages 3B and 4. Anti-vascular endothelial growth factor intravitreal injections may offer new prospects for these patients. METHODS: This study is a retrospective review of all consecutive patients with Coats disease treated with neoadjuvant or adjuvant intravitreal ranibizumab plus conventional and amblyopia treatment as appropriate. RESULTS: Nine patients (median age, 13 months) presenting Coats Stages 3B and 4 (5 and 4 eyes, respectively) were included. Iris neovascularization resolved within 2 weeks and retinal reapplication within 4 months in all patients. At last follow-up, globe survival was 100% with anatomical success in 8 of the 9 eyes. With a median follow-up of 50 months, fibrotic vitreoretinopathy was developed in 5 of the 9 cases, one leading to tractional retinal detachment and ultimately phthisis bulbi. The remaining 4 of the 9 eyes achieved some vision (range, 0.02-0.063). CONCLUSION: To the best of the authors' knowledge, this is the largest reported series of late-stage Coats undergoing anti-vascular endothelial growth factor therapy, a homogenous cohort of patients treated with a single agent and with the longest follow-up. This study supports the role of ranibizumab in advanced disease by transient restoration of the hemato-retinal barrier and suppression of neovascularization to facilitate classic treatment. At the last follow-up, the authors report unprecedented anatomical success and functional outcome.

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The antidepressant selective serotonin transporter inhibitors (SSRIs) are clinically active after a delay of several weeks. Indeed, the rapid increase of serotonin (5-HT) caused by SSRIs, stimulates the 5-HT1A autoreceptors, which exert a negative feedback on the 5-HT neurotransmission. Only when autoreceptors are desensitized, can SSRIs exert their therapeutic activity. The 5-HT1A receptor antagonist pindolol has been used to accelerate the clinical effects of antidepressant by preventing the negative feedback. Using the a-[11C]methyl-L-tryptophan/positron emission tomography (PET), the goal of the present double-blind, randomized study was to compare the changes in a-[11C]methyl-L-tryptophan trapping, an index of serotonin synthesis, in patients suffering from unipolar depression treated with the SSRI citalopram (20 mg/day) plus placebo versus patients treated with citalopram plus pindol (7.5 mg/day). PET and Hamilton depression rating scale (HDRS-17) were performed at baseline, and after 10 and 24 days of antidepressant treatment. Results show that the combination citalopram plus pindol, compared to citalopram alone shows a more rapid and greater increase of an index of 5-HT synthesis in prefrontal cortex (BA 9). This research is the first human PET study demonstrating that, after 24 days, the combination SSRIs plus pindolol produces a greater increase of the metabolism of serotonin in the prefrontal cortex, an area associated to depressive symptoms.

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BACKGROUND: In 2004, a randomised phase III trial by the European Organisation for Research and Treatment of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trials Group (NCIC) reported improved median and 2-year survival for patients with glioblastoma treated with concomitant and adjuvant temozolomide and radiotherapy. We report the final results with a median follow-up of more than 5 years. METHODS: Adult patients with newly diagnosed glioblastoma were randomly assigned to receive either standard radiotherapy or identical radiotherapy with concomitant temozolomide followed by up to six cycles of adjuvant temozolomide. The methylation status of the methyl-guanine methyl transferase gene, MGMT, was determined retrospectively from the tumour tissue of 206 patients. The primary endpoint was overall survival. Analyses were by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT00006353. FINDINGS: Between Aug 17, 2000, and March 22, 2002, 573 patients were assigned to treatment. 278 (97%) of 286 patients in the radiotherapy alone group and 254 (89%) of 287 in the combined-treatment group died during 5 years of follow-up. Overall survival was 27.2% (95% CI 22.2-32.5) at 2 years, 16.0% (12.0-20.6) at 3 years, 12.1% (8.5-16.4) at 4 years, and 9.8% (6.4-14.0) at 5 years with temozolomide, versus 10.9% (7.6-14.8), 4.4% (2.4-7.2), 3.0% (1.4-5.7), and 1.9% (0.6-4.4) with radiotherapy alone (hazard ratio 0.6, 95% CI 0.5-0.7; p<0.0001). A benefit of combined therapy was recorded in all clinical prognostic subgroups, including patients aged 60-70 years. Methylation of the MGMT promoter was the strongest predictor for outcome and benefit from temozolomide chemotherapy. INTERPRETATION: Benefits of adjuvant temozolomide with radiotherapy lasted throughout 5 years of follow-up. A few patients in favourable prognostic categories survive longer than 5 years. MGMT methylation status identifies patients most likely to benefit from the addition of temozolomide. FUNDING: EORTC, NCIC, Nélia and Amadeo Barletta Foundation, Schering-Plough.

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Tyrosine kinase receptors lead to rapid activation of phosphatidylinositol 3-kinase (PI3 kinase) and the subsequent formation of phosphatidylinositides (PtdIns) 3,4-P2 and PtdIns 3,4, 5-P3, which are thought to be involved in signaling for glucose transporter GLUT4 translocation, cytoskeletal rearrangement, and DNA synthesis. However, the specific role of each of these PtdIns in insulin and growth factor signaling is still mainly unknown. Therefore, we assessed, in the current study, the effect of SH2-containing inositol phosphatase (SHIP) expression on these biological effects. SHIP is a 5' phosphatase that decreases the intracellular levels of PtdIns 3,4,5-P3. Expression of SHIP after nuclear microinjection in 3T3-L1 adipocytes inhibited insulin-induced GLUT4 translocation by 100 +/- 21% (mean +/- the standard error) at submaximal (3 ng/ml) and 64 +/- 5% at maximal (10 ng/ml) insulin concentrations (P < 0.05 and P < 0.001, respectively). A catalytically inactive mutant of SHIP had no effect on insulin-induced GLUT4 translocation. Furthermore, SHIP also abolished GLUT4 translocation induced by a membrane-targeted catalytic subunit of PI3 kinase. In addition, insulin-, insulin-like growth factor I (IGF-I)-, and platelet-derived growth factor-induced cytoskeletal rearrangement, i.e., membrane ruffling, was significantly inhibited (78 +/- 10, 64 +/- 3, and 62 +/- 5%, respectively; P < 0.05 for all) in 3T3-L1 adipocytes. In a rat fibroblast cell line overexpressing the human insulin receptor (HIRc-B), SHIP inhibited membrane ruffling induced by insulin and IGF-I by 76 +/- 3% (P < 0.001) and 68 +/- 5% (P < 0.005), respectively. However, growth factor-induced stress fiber breakdown was not affected by SHIP expression. Finally, SHIP decreased significantly growth factor-induced mitogen-activated protein kinase activation and DNA synthesis. Expression of the catalytically inactive mutant had no effect on these cellular responses. In summary, our results show that expression of SHIP inhibits insulin-induced GLUT4 translocation, growth factor-induced membrane ruffling, and DNA synthesis, indicating that PtdIns 3,4,5-P3 is the key phospholipid product mediating these biological actions.