148 resultados para G gamma 13
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The study evaluated, in early post-partum anoestrous Nelore cows, if the increase in plasma oestradiol (E2) concentrations in the pre-ovulatory period and/or progesterone priming (P4 priming) preceding ovulation, induced by hormonal treatment, reduces the endogenous release of prostaglandin PGF(2)alpha and prevents premature lysis of the corpus luteum (CL). Nelore cows were subjected to temporary calf removal for 48 h and divided into two groups: GPE/eCG group (n = 10) and GPG/eCG group (n = 10). Animals of the GPE/eCG group were treated with a GnRH agonist. Seven days later, they received 400 ID of eCG, immediately after PGF(2)alpha treatment, and on day 0, 1.0 mg of oestradiol benzoate (EB). Cows of the GPG/eCG group were similarly treated as those of the GPE/eCG group, except that EB was replaced with a second dose of GnRH. All animals were challenged with oxytocin (OT) 9, 12, 15 and 18 days after EB or GnRH administration and blood samples were collected before and 30 min after OT. Irrespective of the treatments, a decline in P4 concentration on day 18 was observed for cows without P4 priming. However, animals exposed to P4 priming, treated with EB maintained high P4 concentrations (8.8 +/- 1.2 ng/ml), whereas there was a decline in P4 on day 18 (2.1 +/- 1.0 ng/ml) for cows that received GnRH to induce ovulation (p < 0.01). Production of 13,14-dihydro-15-keto prostaglandin F-2 alpha (PGFM) in response to OT increased between days 9 and 18 (p < 0.01), and this increase tended to be more evident in animals not exposed to P4 priming (p < 0.06). In conclusion, the increase in E2 during the pre-ovulatory period was not effective in inhibiting PGFM release, which was lower in P4-primed than in non-primed animals. Treatment with EB promoted the maintenance of elevated P4 concentrations 18 days after ovulation in P4-primed animals, indicating a possible beneficial effect of hormone protocols containing EB in animals with P4 priming.
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The influence of silver additions on the structure and phase transformation of the Cu-13 wt % Al alloy was studied by differential thermal analysis, X-ray diffraction, scanning electron microscopy and energy dispersive analysis of X-rays. The results indicate that the presence of silver modifies the phase-stability field, the transition temperature and the structure of the alloy. These effects are more pronounced for silver concentrations up to 8 wt %.
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The WWγ triple gauge boson coupling parameters are studied using pp̄rarr; νγ+X(=e,μ) events at s=1.96 TeV. The data were collected with the D0 detector from an integrated luminosity of 162pb-1 delivered by the Fermilab Tevatron Collider. The cross section times branching fraction for pp̄→W(γ)+X→ νγ+X with ETγ>8 GeV and ΔR γ> 0.7 is 14.8±1.6(stat)±1.0(syst) ±1.0(lum)pb. The one-dimensional 95% confidence level limits on anomalous couplings are -0.88<Δκγ<0.96 and -0. 20<λγ<0.20. © 2005 The American Physical Society.
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We present a study of eeγ and μμγ events using 1109 (1009) pb-1 of data in the electron (muon) channel, respectively. These data were collected with the DØ detector at the Fermilab Tevatron p over(p, ̄) collider at sqrt(s) = 1.96 TeV. Having observed 453 (515) candidates in the eeγ (μμγ) final state, we measure the Zγ production cross section for a photon with transverse energy ET > 7 GeV, separation between the photon and leptons Δ Rℓ γ > 0.7, and invariant mass of the di-lepton pair Mℓ ℓ > 30 GeV / c2, to be 4.96 ± 0.30 (stat . + syst .) ± 0.30 (lumi .) pb, in agreement with the Standard Model prediction of 4.74 ± 0.22 pb. This is the most precise Zγ cross section measurement at a hadron collider. We set limits on anomalous trilinear Zγγ and ZZγ gauge boson couplings of - 0.085 < h30 γ < 0.084, - 0.0053 < h40 γ < 0.0054 and - 0.083 < h30 Z < 0.082, - 0.0053 < h40 Z < 0.0054 at the 95% C.L. for the form-factor scale Λ = 1.2 TeV.
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A major challenge in cancer radiotherapy is to deliver a lethal dose of radiation to the target volume while minimizing damage to the surrounding normal tissue. We have proposed a model on how treatment efficacy might be improved by interfering with biological responses to DNA damage using exogenous electric fields as a strategy to drastically reduce radiation doses in cancer therapy. This approach is demonstrated at this Laboratory through case studies with prokaryotes (bacteria) and eukaryotes (yeast) cells, in which cellkilling rates induced by both gamma radiation and exogenous electric fields were measured. It was found that when cells exposed to gamma radiation are immediately submitted to a weak electric field, cell death increases more than an order of magnitude compared to the effect of radiation alone. This finding suggests, although does not prove, that DNA damage sites are reached and recognized by means of long-range electric DNA-protein interaction, and that exogenous electric fields could destructively interfere with this process. As a consequence, DNA repair is avoided leading to massive cell death. Here we are proposing the use this new technique for the design and construction of novel radiotherapy facilities associated with linac generated gamma beams under controlled conditions of dose and beam intensity.
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This study's objective is to evaluate the photosynthates partitioning and source-sink relationships, in vegetative and reproductive twigs of sweet passion fruit, using the carbon-13, stable isotope of carbon. The leaves of vegetative and reproductive twigs were placed in a sealed chamber and 13CO 2 were injected for 30 minutes. After six hours, the different organs of the twig were collected and immersed in liquid nitrogen (-196°C). All plant samples were oven-dried, powdered and combusted in an elemental analyzer. The results showed that the methodology was efficient to evaluate the partitioning of photosynthates. In the vegetative twigs, the new open leaves, the closed leaves and growth meristem were the principal sink for the source leaves enriched with 13CO 2. In the reproductive twigs with only flowers buds, the source-sink relationship was changed and the flowers buds turn to be the principal sink and the growing leaves were secondary sinks. The presence of young fruits changed again the source-sink relationship of the twig, and they were the principal sinks. The apical leaves, with 60% of final leaf area were also a sink for photosynthates.
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Background: To investigate the effect of lisinopril on cardiac remodeling induced by smoking. Material/Methods: Rats were allocated into 3 groups: group CON (n=8): control; group CSE (n=8): cigarette smoke exposure; group CSE-LIS (n=8): exposed to tobacco smoke and treated with lisinopril. Results: After 2 months, the tail systolic pressure was lower in CSE-LIS (CON=116 ±27 mm Hg, CSE=126±16, CSE-LIS=89±12; P<.001). CSE animals showed higher left ventricular systolic diameter (CON=8.25±2.16 mm/kg, CSE=11.5±1.3, CSE-LIS=9.27±2.00; P=.009) and myocyte cross-sectional area (CON=245±8 μm2, CSE=260±17, CSE-LIS=238±12; P=.01) than CON and CSE-LIS. The ejection fraction (CON =0.91±0.02, CSE=0.86±0.02, CSE-LIS=0.92±0.03; P=.002) and fractional shortening (CON=55.7±4.41%, CSE=48.7±3.43, CSE-LI=58.2±7.63; P=.006) were lower in CSE group than CON and CSE-LIS. CSE and CSE-LIS animals showed higher collagen amounts (CON=3.49±0.95%, CSE= 5.01±1.58, CSE-LIS=5.27±0.62; P=.009) than CON. CON group showed a higher connexin 43 amount in the intercalated disc (CON=3.70±0.38, CSE=2.13±0.53; CSE-LIS=2.17±0.73; P=.004) than CSE and CSE-LIS. There were no differences in IFN-g or TNF-a cardiac levels among the groups. Conclusions: Lisinopril attenuated both morphologic and functional abnormalities induced by exposure to tobacco smoke. In addition, this effect was associated with diminished blood pressure, but not alterations in connexin 43 distribution, cytokine production or collagen amount. © Med Sci Monit, 2010.
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Calcium phosphate-based bioactive ceramics in various physical and chemical formulations have been extensively utilized as biomaterials for bone regeneration/conduction. However, the determination of their in vivo temporal behavior from the short to long term in humans has been a challenge due to the lack of physical reference for morphologic and morphometric evaluation. The present study evaluated bone morphology and morphometry (bone-to-implant contact [BIC]) around plasma-sprayed hydroxyapatite (PSHA)-coated endosseous implants that were retrieved due to prosthetic reasons while successfully in function at the posterior region of the jaws from as early as 2 months to ~13 years after a 6-month healing period after placement. Bone morphology was evaluated by light microscopy, and BIC was determined using computer software. Irrespective of the time in vivo, lamellar bone was observed in close contact with the implant PSHA-coated surface and between plateaus. BIC ranged from ~35-95%, was highly directional, and Haversian-like osteonic morphology between plateaus was observed for most implants. The PSHA coating was present with little variation in thickness between the samples retrieved regardless of time in vivo. © 2010 by Begell House, Inc.
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In this work, is presented an alternative and non conventional technique for evaluate the water amount present in the hydrated ethanol used as automotive fuel. The standard technique used in this kind of measure is the use of densimeter. The proposal of this work is based on the measure of the linear attenuation coefficient of hydrated ethanol, using the gamma-ray attenuation technique. The water amount, in volume, can be determined knowing the linear attenuation coefficient of hydrated ethanol. Samples of hydrated ethanol, collected at fuel stations, located in Sorocaba, SP, Brazil, were analyzed and the results showed the feasibility of the technique. © 2011 American Institute of Physics.
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Fetal hemoglobin (Hb F), formed by two alpha globin chains (α) and two gamma chains (γ) (α2 γ2), has reduced expression in adults, ranging from 0 to 1% of total hemoglobin. Increased levels of Hb F are due to mutations in the β-globin family, which cause hereditary persistence of fetal hemoglobin (HPFH) and delta-beta thalassemia (δβ-thalassemia).The control of the production takes place by the regulatory region and regions outside the β-globin family, among them 2q16, 6q23, 8q, and Xp22.2.The aims of this study were to determine the presence and frequency of two mutations for δβ-thalassemia, the XmnI polymorphism and β-globin haplotypes in healthy individuals with increased Hb F in the State of São Paulo. We analyzed 60 samples of peripheral blood of healthy adults, without complaints of anemia. The samples were separated into two groups according to Hb F level: group I - 34 samples with Hb F ranging from 2 to 15% and group II - 26 samples with Hb F over 15%. In relation to the polymorphisms examined, we found three heterozygous individuals (5%) for Spanish δβ-thalassemia, belonging to group I, whose Hb F levels were within the normal range.The Sicilian δβ-thalassemia mutation was not found, indicating the need to study other polymorphisms related to the increase of Hb F in adult life.The frequency of XmnI polymorphism was 33.3% and the mean Hb F levels were 15.48 ± 11.69%.The frequency observed in our study for this polymorphic site is higher than that found in the literature for healthy subjects.This polymorphism was more prevalent in individuals with Hb F levels below 15%. For four samples positive for this polymorphism, the Hb F levels were explained by the presence of HPFH and Spanish δβ-thalassemia mutations, so that the presence of the XmnI polymorphic site was not a determinant in the overexpression of γ-globin genes. Regarding β-globin haplotypes, 18 alleles and 27 distinct genotypic patterns were found.The pattern Atp1/Atp2 was the mostfrequent genotype (13.72%).Of the 18 alleles, 13 showed atypical patterns.The results show that the haplotype V was the most frequent (27.45%), followed by atypical Atp2 (13.72%) and Atp1 (11.76%), and that there was a higher correlation with the presence of HPFH and XmnI polymorphism.The high frequency of haplotype V in our samples and high frequency of atypical haplotypes may reflect a high rate of miscegenation in this population, suggesting an ethnic characteristic for the Brazilian population, requiring the evaluation of population genetic markers to corroborate this hypothesis. © FUNPEC-RP.
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Ganoderma lucidum is an edible medicinal mushroom with immunomodulatory and antitumor properties, which are mainly attributed to polysaccharides and triterpenes that can be isolated from mycelia, fruiting bodies and spores. G. lucidum has been us d in a powdered form, as a medicinal beverage and a nutraceutical food (usually dried). In the present review we report some historical facts and the experimental evidence that polysaccharides and triterpenes obtained from this mushroom present potential antitumor activity. Direct effects on tumor cells include induction of apoptosis and interference in the cell cycle, whereas indirect effects are based on the modulation of immune response, usually impaired by cancer cells. Data indicate that G. lucidum can be used as a complementary tool for treatment of cancer patients. © by São Paulo State University.
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This work describes the efficiency of photoelectrocatalysis based on Ti/TiO2 nanotubes in the degradation of the azo dyes Disperse Red 1, Disperse Red 13 and Disperse Orange 1 and to remove their toxic properties, as an alternative method for the treatment of effluents and water. For this purpose, the discoloration rate, total organic carbon (TOC) removal, and genotoxic, cytotoxic and mutagenic responses were determined, using the comet, micronucleus and cytotoxicity assays in HepG2 cells and the Salmonella mutagenicity assay. In a previous study it was found that the surfactant Emulsogen could contribute to the low mineralization of the dyes (60% after 4h of treatment), which, in turn, seems to account for the mutagenicity of the products generated. Thus this surfactant was not added to the chloride medium in order to avoid this interference. The photoelectrocatalytic method presented rapid discoloration and the TOC reduction was ≥87% after 240min of treatment, showing that photoelectrocatalysis is able to mineralize the dyes tested. The method was also efficient in removing the mutagenic activity and cytotoxic effects of these three dyes. Thus it was concluded that photoelectrocatalysis was a promising method for the treatment of aqueous samples. © 2013 Elsevier Ltd.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Ciência da Computação - IBILCE