986 resultados para meglumine acridone acetate (MAA)


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The oxidation potential of pulsed corona discharge concerning aqueous impurities is limited in respect to certain refractory compounds. This may be enhanced in combination of the discharge with catalysis/photocatalysis as developed in homogeneous gas-phase reactions. The objective of the work consists of testing the hypothesis of oxidation potential enhancement in combination of the discharge with TiO2 photocatalysis applied to aqueous solutions of refractory oxalate. Meglumine acridone acetate was included for meeting the practical needs. The experimental research was undertaken into oxidation of aqueous solutions under conditions of various target pollutant concentrations, pH and the pulse repetition rate with plain electrodes and the electrodes with TiO2 attached to their surface. The results showed no positive influence of the photocatalyst, the pollutants were oxidized with the rate identical within the accuracy of measurements. The possible explanation for the observed inefficiency may include low UV irradiance, screening effect of water and generally low oxidation rate in photocatalytic reactions. Further studies might include combination of electric discharge with ozone decomposition/radical formation catalysts.

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Tässä kandidaatintyössä selvitettiin, onko 28 vuorokautta riittävä aika sinkillä pilaantuneen maaperän massastabilointiin, ja kuinka sinkin esiintymismuoto vaikuttaa sen stabilointiaikaan. Kokeellisessa osassa jäljiteltiin malmijätteessä, orgaanisessa aineksessa sekä liuenneena maaperässä esiintyvän sinkin stabiloitumista lisäämällä maanäytteeseen sinkkiä eri yhdisteinä; sinkkirakeina, -kloridina ja -asetaattina. Näytteet stabiloitiin sementti-lentotuhkaseoksella 1–28 vuorokauden pituisia ajanjaksoja, minkä jälkeen ne kuvattiin pyyhkäisyelektronimikroskoopilla (SEM) ja niille tehtiin liukoisuustestit. Liukoisuustestien tuloksista voidaan huomata sinkkikloridin stabiloituvan jo ensimmäisen vuorokauden aikana ja pysyvän samalla tasolla koko tarkasteluajan. Sinkkirakeiden ja -asetaatin stabiloituminen ei ole yhtä tasaista; alun sitoutumisen jälkeen niiden liukoisuuksissa on havaittavissa selkeät piikit 21 vuorokauden kohdalla. Tämän jälkeen ne alkavat sitoutua uudelleen. Tulosten perusteella sinkin esiintymismuoto vaikuttaa sen stabilointiaikaan, eikä 28:aa vuorokautta voida pitää riittävänä aikana sinkillä pilaantuneen maa-aineksen stabilointiin. Vaikka liukoinen sinkki stabiloituu jo yhdessä vuorokaudessa, ei malmijätteessä tai orgaanisessa aineksessa esiintyvä sinkki ehdi stabiloitua vakaalle tasolle vielä 28 vuorokaudenkaan aikana. Tämä tulisi ottaa huomioon suunniteltaessa ja toteutettaessa sinkkiä sisältävien maiden kunnostushankkeita.

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To compare variations in bone mineral density (BMD) and body composition (BC) in depot-medroxyprogesterone acetate (DMPA) users and nonusers after providing counselling on healthy lifestyle habits. An exploratory study in which women aged 18 to 40 years participated: 29 new DMPA users and 25 new non-hormonal contraceptive users. All participants were advised on healthy lifestyle habits: sun exposure, walking and calcium intake. BMD and BC were assessed at baseline and 12 months later. Statistical analysis included the Mann-Whitney test or Student's t-test followed by multiple linear regression analysis. Compared to the controls, DMPA users had lower BMD at vertebrae L1 and L4 after 12 months of use. They also had a mean increase of 2 kg in total fat mass and an increase of 2.2% in body fat compared to the non-hormonal contraceptive users. BMD loss at L1 was less pronounced in DMPA users with a calcium intake ≥ 1 g/day compared to DMPA users with a lower calcium intake. DMPA use was apparently associated with lower BMD and an increase in fat mass at 12 months of use. Calcium intake ≥ 1 g/day attenuates BMD loss in DMPA users. Counselling on healthy lifestyle habits failed to achieve its aims.

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Data on record regarding weight variation in depot-medroxyprogesterone acetate (DMPA) and levonorgestrel-releasing intrauterine system (LNG-IUS) users are controversial. To date, no studies have yet evaluated weight variation in DMPA and LNG-IUS users in up to ten years of use compared to non-hormonal contraceptive users. A retrospective study analysed weight variations in 2138 women using uninterruptedly DMPA (150 mg intramuscularly, three-monthly; n = 714), the LNG-IUS (n = 701) or a copper-intrauterine device (Cu-IUD; n = 723). At the end of the first year of use, there was a mean weight increase of 1.3 kg, 0.7 kg and 0.2 kg among the DMPA-, LNG-IUS- and Cu-IUD users, respectively, compared to weight at baseline (p < 0.0001). After ten years of use, the mean weight had risen by 6.6 kg, 4.0 and 4.9 kg among the DMPA-, LNG-IUS- and Cu-IUD users, respectively. DMPA-users had gained more weight than LNG-IUS- (p = 0.0197) and than Cu-IUD users (p = 0.0294), with the latter two groups not differing significantly from each other in this respect (p = 0.5532). Users of hormonal and non-hormonal contraceptive methods gained a significant amount of weight over the years. DMPA users gained more weight over the treatment period of up to ten years than women fitted with either a LNG-IUS or a Cu-IUD.

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This work presents a mathematical model for the vinyl acetate and n-butyl acrylate emulsion copolymerization process in batch reactors. The model is able to explain the effects of simultaneous changes in emulsifier concentration, initiator concentration, monomer-to-water ratio, and monomer feed composition on monomer conversion, copolymer composition and, to lesser extent, average particle size evolution histories. The main features of the system, such as the increase in the rate of polymerization as temperature, emulsifier, and initiator concentrations increase are correctly represented by the model. The model accounts for the basic features of the process and may be useful for practical applications, despite its simplicity and a reduced number of adjustable parameters.

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All textile uses of cellulose acetate involve acetone recovery, which, because of safety issues, results in large installations, in order to work with dilute streams. This compromises the efficiency of all of the involved unit operations, in this case, acetone absorption in cold water, acetone distillation, and water chilling, making them more expensive. The present article proposes the improvement of the absorption of acetone in water, traditionally performed with sieve trays, by using structured packing instead. The advantageous implementation was enabled through the utilization of a calculation methodology based on concepts of thermodynamic equilibrium of the binary acetone/water system and empirical relations that allow the evaluation of the hydrodynamics of the proposed modification.

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The extent of mixing in blends of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) (27% HV) and poly(vinyl acetate) (PVAc) has been measured using a number of different techniques, principally solid-state NMR. Differential scanning calorimetry DSC measurements indicated effective mixing of the polymer chains on a scale of several nanometres. The results of H-1 T-1 and H-1 T-1rho. measurements confirm intimate mixing of the chains. A change on blending in the H-1 T-1rho, and the H-1 NMR line width of the signal from the protons of PVAc was consistent with an increase in the amplitude and frequency of motion of this component. The PVAc chains reside within the inter-lamellar space, as confirmed by spin diffusion measurements after H-1 T-1rho preparation. (C) 2003 Society of Chemical Industry.

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In the title compound, C13H14N2O7, steric crowding around the aromatic ring results in significant out-of-plane twisting of the nitro, methoxy, acetoxy and 2-nitropropenyl functional groups. These distortions are explained by comparison with less congested substituted benzene analogues.

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Leishmaniasis is a parasitic disease caused by the intramacrophage protozoa Leishmania spp. and may be fatal if left untreated. Although pentavalent antimonials are toxic and their mechanism of action is unclear, they remain the first-line drugs for treatment of leishmaniasis. An effective therapy could be achieved by delivering antileishmanial drugs to the site of infection. Compared with free drugs, antileishmanial agent-containing liposomes are more effective, less toxic and have fewer adverse side effects. The aim of this study was to develop novel meglumine antimoniate (MA)-containing liposome formulations and to analyse their antileishmanial activity and uptake by macrophages. Determination of the 50% inhibitory concentration (IC(50)) values showed that MA-containing liposomes were >= 10-fold more effective than the free drug, with a 5-fold increase in selectivity index, higher activity and reduced macrophage toxicity. The concentration required to kill 100% of intracellular amastigotes was >= 40-fold lower when MA was encapsulated in liposomes containing phosphatidylserine compared with the free drug. Fluorescence microscopy analysis revealed increased uptake of fluorescent liposomes in infected macrophages after short incubation times compared with non-infected macrophages. In conclusion, these data suggest that MA encapsulated in liposome formulations is more effective against Leishmania-infected macrophages than the non-liposomal drug. Development of liposome formulations is a valuable approach to the treatment of infectious diseases involving the mononuclear phagocyte system. (C) 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

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Background: The study was conducted to determine whether the use of a combined oral contraceptive (COC) or depot medroxyprogesterone acetate (DMPA) interferes with endothelial function. Study Design: The study was conducted on 100 women between the ages of 18 and 30 years. Fifty women had not used hormonal contraception (control group) for at least 12 months, 25 were current users of a COC (ethinylestradiol 30 mcg+levonorgestrel 150 mcg) and 25 were current users of DMPA (150 mg) for at least a 6-month period. All women were evaluated for brachial flow-mediated dilation (FMD), intima-media thickness, carotid distensibility and stiffness index, arterial pressure, body mass index, waist circumference, heart rate and lipid profile. Results: A significant difference in FMD was observed between the COC and control groups (6.4 +/- 2.2% vs. 8,7 +/- 3.4%, p<.01) and between the DMPA and control groups (6.2 +/- 2.1% vs. 8.7 +/- 3.4%, p<.01). The DMPA group had lower values of total cholesterol (TC) and low-density lipoprotein (LDL-C) than COC users and the control group (TC: DMPA=139.9 +/- 21.5 mg/dL vs. controls=167.1 +/- 29.2 mg/dL vs. COC=168.2 +/- 37.5. p=.001; LDL-C: DMPA-85.3 +/- 20.1 mg/dL vs. controls=102 +/- 24.5 mg/dL vs. COC=106.7 +/- 33.3 mg/dL, p=.01). The control group had higher levels of high-density lipoprotein (HDL-C) than the DMPA and COC groups (controls=52.4 +/- 14.1 mg/dL vs. DMPA=42.2 +/- 7.2 mg/dL vs. COC=45.4 +/- 9.1 mg/dL, p=.001). No significant differences were observed regarding the other variables. Conclusions: FMD was lower among COC and DMPA users, Suggesting that these hormonal contraceptives may promote endothelial dysfunction. (C) 2009 Elsevier Inc. All rights reserved.

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Despite the probable inhibitory effects of GnRH analogues on ovarian steroidogenesis in vitro, their association with assisted reproduction protocols shows favorable results. This suggests that there are important differences in the behaviors of these drugs when administered in vivo versus in vitro. To clarify these differences, this study was designed to analyze the effect of leuprolide acetate (LA) on ovarian steroidogenesis in women undergoing In Vitro Fertilization (IVF). A prospective, randomized open label study was conducted on 14 women (26-35 years): seven receiving only gonadotrophins (Group 1) and seven receiving gonadotrophin plus LA at 1mg/day (Group 2). The LA in vivo effect was determined with serum and follicular fluid (FF) samples and via luteinized granulosa cell cultivation (GCC), where cells were obtained during oocyte retrieval after ovarian hyperstimulation. In vitro analysis was performed via addition of LA to GCC only for Group 1 (without LA) at progressively higher concentrations (0, 10(-12), 10(-9) and 10(-6) M). In vivo, the main observation was a reduction in androgen production in Group 2, represented by lower androstenedione production in FF (G1 = 6479 +/- 3458; G2 = 3021 +/- 1119 ng/ml; p = 0.04) and a lower testosterone peak in GC at 96 h (G1 = 0.64 +/- 0.12 ng/ml; G2 = 0.50 +/- 0.19ng/ml; P = 0.02), but a higher fertilization rate (G1 = 67%; G2 = 83%; p = 0.009). in vitro, testosterone, estradiol and progesterone were also reduced by LA, even though this reduction occurred for progesterone only at the highest LA dosage (10(-6) M; 606.0 +/- 114.3 ng/ml versus 1524.0 +/- 246.5 ng/ml; p=0.02). Results show that LA reduces ovarian steroidogenesis in vivo by essentially inhibiting androgen synthesis; whereas, in vitro, ovarian steroidogenesis is reduced overall. (C) 2008 Elsevier Inc. All rights reserved.

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Background Familial male-limited precocious puberty (FMPP) or testotoxicosis is a rare gonadotrophin-independent form of sexual precocity caused by constitutively activating mutations of the LH receptor. Several clinical therapeutic approaches have been reported for this disorder, but with a paucity of long-term outcome data. Objective To evaluate the long-term treatment of testotoxicosis with cyproterone acetate or ketoconazole. Design A multicentric retrospective clinical study. Patients Ten boys from eight unrelated Brazilian families who carried known LH-receptor activating mutations were treated with 70 mg/m(2) cyproterone acetate (n = 5) or 10 mg/kg ketoconazole (n = 5) for a mean period of 5 and 8 years, respectively. Measurements Chronological and bone ages, bone age/chronological age ratio, target height (TH) range, adult height, basal and GnRH-stimulated gonadotrophin levels and basal testosterone levels were assessed. Results Growth velocity decreased significantly during treatment with cyproterone acetate or ketoconazole when compared to pretreatment value in each group (P < 0.05). Bone age/chronological age ratio decreased significantly after cyproterone acetate or ketoconazole therapy. Basal testosterone levels were significantly lower in patients undergoing ketoconazole compared to cyproterone acetate treatment [0.6 +/- 0.3 nmol/l (42 +/- 21 ng/dl) vs. 5.6 +/- 4.0 nmol/l (392 +/- 280 ng/dl); P < 0.05], as expected. Secondary gonadotrophin-dependent precocious puberty occurred at a similar frequency (40%) in both groups. Five patients have attained adult height and two patients have already reached 90% of their adult height. Two of them achieved their TH range and one patient, for whom TH was not available, had an adult height of 0.3 SDS. Four boys (two in each group) did not attain their TH range. Conclusion Long-term treatment with cyproterone acetate or ketoconazole resulted in similar outcomes without important side-effects in boys with testotoxicosis. However, both therapies showed limited efficacy in attaining normal adult height.

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The objective was to compare pharmacological strategies aiming to inhibit prostaglandin F2 alpha (PGF(2 alpha)) synthesis (flunixin meglumine; FM), stimulate growth of the conceptus (recombinant bovine somatotropin; bST) and progesterone (P(4)) synthesis (human chorionic gonadotropin; hCG), as well as their combinations, regarding their ability to improve pregnancy rates in beef cattle. Lactating Nelore cows (N = 975), 35 to 70 days postpartum, were synchronized and inseminated by timed artificial insemination (TAT) on Day 0. On Day 7, cattle were allocated into eight groups and received one of the following treatments: saline (S) on Days 7 and 16 (Group Control); S on Day 7 and FM on Day 16 (Group FM); bST on Day 7 and S on Day 16 (Group bST); bST on Day 7 and FM on Day 16 (Group bST + FM); hCG on Day 7 and S on Day 16 (Group hCG); hCG on Day 7 and FM on Day 16 (Group hCG + FM); bST and hCG on Day 7 and S on Day 16 (Group bST + hCG), or bST and hCG on Day 7 and FM on Day 16 (Group bST + hCG + FM). The aforementioned treatments were administered at the following doses: 2.2 mg/kg FM (Banamine (R); Intervet Schering-Plough, Cotia, SP, Brazil), 500 mg bST (Boostin (R); Intervet Schering-Plough), and 2500 IU hCG (Chorulon (R); Intervet Schering-Plough). Pregnancy diagnosis was performed 40 days after TAI by transrectal ultrasonography. Pregnancy rates were not significantly different among treatments. However, there was a main effect of hCG treatment to increase pregnancy rates (63.0 vs. 55.4%; P = 0.001). Concentrations of P(4) did not differ significantly among groups on Day 7 or on Day 16. However, consistent with the higher pregnancy rates, hCG increased P(4) concentrations on Day 16 (10.6 vs. 9.6 ng/mL, respectively; P = 0.05). We concluded that hCG treatment 7 days after TAI improved pregnancy rates of lactating Nelore cows, possibly via a mechanism leading to induction of higher P(4) concentrations, or by reducing the luteolytic stimulus during maternal recognition of pregnancy. (C) 2011 Elsevier Inc. All rights reserved.

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The structure of the product from the free radical bulk copolymerization of methyl methacrylate (MMA) and allyl acetate (AAc) was investigated. The mole fraction of AAc plays an important role in the copolymerization of these two monomers. Molecular weight (MW) and molecular weight distribution (MWD) are completely altered when the feed composition is dominantly AAc. NMR spectroscopy confirmed the incorporation of AAc into the polymer. However, no allyl-allyl linkages were observed at low conversions. T-g was found to be affected by the incorporation of AAc into the polymer. (C) 2001 Society of Chemical Industry.

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Free radical bulk copolymerization of methyl methacrylate (MMA) and allyl acetate (AAc) has been investigated using electron spin resonance (ESR) and FT-near infrared (FTNIR) spectroscopy. Data are used to evaluate the rate constants. The mole fraction of AAc plays an important role in the copolymerization of these two monomers. AAc not only delays the Trommsdorff effect but also increases the onset of percentage total conversion at which the Trommsdorff region begins. With AAc fraction 0.5 and higher, no Trommsdorff effect was observed. Inclusion of AAc into copolymer structure mainly occurs in the Trommsdorf region or when the AAc fraction in the comonomer feed is dominant. This is associated with a drop in the concentration of propagating radicals. However, ESR spectra indicate that the MMA propagating radical is predominant during the reaction. In the comonomer mixtures where a Trommsdorff region can be observed, the addition of AAc does not produce any significant change in k(p) and k(t) in the steady state region. Major changes in k(p) and k(t) are observed after the gel point and glassy state, respectively. (C) 2001 Society of Chemical Industry.