999 research outputs found

    Oxocarbons, pseudo-oxocarbons and squaraines

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    Oxocarbons ions are cyclic compounds presenting unusual electronic and vibrational properties. These molecules anions possess a high symmetry and degree of electronic delocalization, characteristics that have been discussed in several structural and spectroscopic investigations. Compounds in which one or more of the carbonyl oxygen atoms are replaced by other atoms or groups are called pseudo-oxocarbons. Compounds formed by substitution of the carbonyl groups by nitrogen groups former a new class named squaraines. Specificity the dicyanomethylene groups are interesting because of the possibility of further extension of the electronic delocalization and a new coordination site. These molecules also present interesting coordination properties which make these systems potentially useful in crystal engineering research.

    N′-[3-(Hy­droxy­imino)­butan-2-yl­idene]-4-methyl­benzene-1-sulfono­hydrazide

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    In the title compound, C11H15N3O3S, the C—S—N(H)—N linkage is nonplanar, the torsion angle being 75.70 (12)°. The compound has two almost planar fragments linked to the S atom: the hydrazone-derivative fragment [(HONC4H6)N—N(H)–] and the tolyl fragment (C7H7–) have maximum deviations from the mean plane through the non-H atoms of 0.0260 (10) and 0.0148 (14) Å, respectively. The two planar fragments make an inter­planar angle of 79.47 (5)°. In the crystal, mol­ecules are connected through inversion centers via pairs of N—H⋯O and O—H⋯N hydrogen bonds

    1-(2,4,6-Trioxo-1,3-diazinan-5-yl­idene)thio­semicarbazide

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    The title mol­ecule, C5H5N5O3S, is approximately planar, with a maximum deviation from the mean plane through the non-H atoms of 0.182 (3) Å for the amine N atom. In the crystal, mol­ecules are connected via N—H⋯O and N—H⋯S inter­actions, building a three-dimensional hydrogen-bonded network. Additionally, a weak intra­molecular N—H⋯O hydrogen bond is observed

    Effects of ovariectomy on the secretory apparatus in the right atrial cardiomyocytes of middle-aged mice

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    OBJECTIVE : the aim of the present study was to evaluate the effects of ovariectomy on the secretory apparatus of natriuretic peptides in right atrial cardiomyocytes.METHODS: Nine-month-old mice underwent bilateral ovariectomy or sham surgery. the blood exam of the ovariectomized mice showed results consistent with castrated females. Systolic blood pressure was measured after ovariectomy (9 mo of age) and at the moment of sacrifice (12 mo of age). Fragments of the right atrium were collected and prepared for electron microscopy examination. the following variables were quantified: the quantitative density and area of the natriuretic peptide granules, the relative volume of euchromatin in the nucleus, the number of pores per 10 mu m of the nuclear membrane and the relative volumes of the mitochondria and Golgi complex.RESULTS: the cardiomyocytes obtained from ovariectomized mice indicated that the quantitative density and the area of secretory granules of natriuretic peptides were significantly lower compared with the shamoperated mice. Furthermore, there was a decrease in the relative volume of euchromatin, a lower density of nuclear pores, and lower relative volumes of the mitochondria and Golgi complex in the ovariectomized mice compared with the sham-operated mice. These findings suggest a pool with a low turnover rate, i.e., low synthesis and elimination of natriuretic peptides.CONCLUSION: A lack of estrogen caused hypotrophy of the secretory apparatus in right atrial cardiomyocytes that could explain the weak synthesis of natriuretic peptides in mice. Furthermore, one of the mechanisms of blood pressure control was lost, which may explain, in part, the elevated blood pressure in ovariectomized mice.Univ Sao Judas Tadeu, Dept Anat, ICB USP, São Paulo, BrazilUniv Sao Judas Tadeu, Dept Biol, São Paulo, BrazilUniv Sao Judas Tadeu, Dept Anat, São Paulo, BrazilUniv Cruzeiro Sul, Inst Phys Act Sci & Sports, Grad Program Human Movement Sci, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, São Paulo, BrazilNove Julho Univ, Dept Anat, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Morphol & Genet, São Paulo, BrazilWeb of Scienc

    Correlation between LTR point mutations and proviral load levels among Human T cell Lymphotropic Virus type 1 (HTLV-1) asymptomatic carriers

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    <p>Abstract</p> <p>Background</p> <p>In vitro studies have demonstrated that deletions and point mutations introduced into each 21 bp imperfect repeat of <it>Tax</it>-responsive element (TRE) of the genuine human T-cell leukemia virus type I (HTLV-1) viral promoter abolishes <it>Tax </it>induction. Given these data, we hypothesized that similar mutations may affect the proliferation of HTLV-1i</p> <p>nfected cells and alter the proviral load (PvL). To test this hypothesis, we conducted a cross-sectional genetic analysis to compare the near-complete LTR nucleotide sequences that cover the TRE1 region in a sample of HTLV-1 asymptomatic carriers with different PvL burden.</p> <p>Methods</p> <p>A total of 94 asymptomatic HTLV-1 carriers with both sequence from the 5' long terminal repeat (LTR) and a PvL for <it>Tax </it>DNA measured using a sensitive SYBR Green real-time PCR were studied. The 94 subjects were divided into three groups based on PvL measurement: 31 low, 29 intermediate, and 34 high. In addition, each group was compared based on sex, age, and viral genotypes. In another analysis, the median PvLs between individuals infected with mutant and wild-type viruses were compared.</p> <p>Results</p> <p>Using a categorical analysis, a G232A substitution, located in domain A of the TRE-1 motif, was detected in 38.7% (12/31), 27.5% (8/29), and 61.8% (21/34) of subjects with low, intermediate, or high PvLs, respectively. A significant difference in the detection of this mutation was found between subjects with a high or low PvL and between those with a high or intermediate PvL (both <it>p </it>< 0.05), but not between subjects with a low or intermediate PvL (<it>p </it>> 0.05). This result was confirmed by a non-parametric analysis that showed strong evidence for higher PvLs among HTLV-1 positive individuals with the G232A mutation than those without this mutation (<it>p </it>< 0.03). No significant difference was found between the groups in relation to age, sex or viral subtypes (<it>p</it> > 0. 05).</p> <p>Conclusions</p> <p>The data described here show that changes in domain A of the HTLV-1 TRE-1 motif resulting in the G232A mutation may increase HTLV-1 replication in a majority of infected subjects.</p

    Differences and similarities of postprandial lipemia in rodents and humans

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    The rat has been a mainstay of physiological and metabolic research, and more recently mice. This study aimed at characterizing the postprandial triglyceride profile of two members of the Muridae family: the Wistar rats (Rattus norvegicus albinus) and C57BL/6 mice (Mus musculus) plus comparing them to the profile obtained in humans. Thirty-one male and twelve female Wistar rats, ten C57BL/6 male and nine female mice received a liquid meal containing fat (17%), protein (4%) and carbohydrates (4%), providing 2 g fat/Kg. Thirty-one men and twenty-nine women received a standardized liquid meal containing fat (25%), dextromaltose (55%), protein (14%), and vitamins and minerals (6%), and providing 40 g of fat per square meter of body surface. Serial blood samples were collected at 2, 4, 6, 8 and 10 h after the ingestion in rats, at 1, 2, 3, 4, 5 and 6 h in mice and in humans at 2, 4, 6 and 8 h. Wilcoxon and Mann-Whitney tests were used. The triglyceride responses were evaluated after the oral fat loads. Fasting and postprandial triglyceridemia were determined sequentially in blood sample. AUC, AUIC, AR, RR and late peaks were determined. Rats are prone to respond in a pro-atherogenic manner. The responses in mice were closer to the ones in healthy men. This study presents striking differences in postprandial triglycerides patterns between rats and mice not correlated to baseline triglycerides, the animal baseline body weight or fat load in all animal groups.101CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão te

    Biosorbents in the Metallic Ions Determination

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    This chapter provides an overview and discusses analytical strategies for metallic ions determination using solid phase extraction. Solid phase extraction (SPE) is a much-used technique for extraction and/or concentration of complex samples, so that the analytes present in low concentration were detected mainly using chromatographic methods. However, in recent years, this technique has been widely used in the development of methodologies for metallic ions determination in the deferential samples. This technique shows simplicity and rapidity comparing with other conventional techniques, liquid–liquid extraction, cloud point extraction and others. Solid phase extraction procedures become even more interesting when commercial adsorbents are exchanged for others with higher adsorptive capacity, selectivity, flexibility, economy and low environmental impacts. For this purpose, some inorganic, organic and several natural adsorbents are used. New approaches to obtain adsorbent materials from natural sources such as fungi, bacteria, industrial residues and composting materials have received attention. These materials have been used in the development of analytical methods with varied proposals, such as preconcentration or speciation of metal ions

    Application of Nanofiltration to the Treatment of Acid mine Drainage Waters

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    This study investigated the separation of uranium and other elements in high concentrations from acid mine waters at Caldas Uranium Mining, in the southeast of Brazil, using nanofiltration membranes. Nanofiltrarion is widely used in water treatment due to the lower energy requirements and higher yields than reverse osmosis. Separation characteristics are dependent on both the molecular size and charge of the dissolved species in the feed solution as well as membrane properties. In this investigation the potential of nanofiltration to removed dissolved species like uranium from acid mine water drainage was measured. Two composite aromatic polyamide commercially membranes of FilmTec/Dow were tested and it found that uranium rejections of greater than 90% and also showed potential for the separation of aluminum and manganese

    Os Açores e os impérios : séculos XV a XX

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    [...]. Os Açores não constituem simplesmente um elo da correspondência transatlântica. Aliás, possuem uma identidade bem complexa. Com efeito, se a História evidencia muito a mundividência, apresentando as ilhas como o centro do Mundo, já a literatura ressalta muito o isolamento, resultante do afastamento dos continentes e da descontinuidade territorial, apresentando as ilhas como o fim do Mundo. Curiosamente, a política e os políticos, talvez com maior sentido do pragmatismo e da oportunidade, agem em função das circunstâncias. De facto, proclamam a projecção da universalidade, quando reivindicam mais capacidade de auto-governo, mas insistem na pobreza da ultraperifericidade, quando exigem mais contrapartidas financeiras. Apesar da divergência das perspectivas, atentemos mais na universalidade dos Açores, que historicamente influi na definição das dinâmicas do Atlântico, conferindo maior projecção à Europa
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