955 resultados para 2-hydroxypropyl-beta-cyclodextrin
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Evidence demonstrates that sympathetic nervous system (SNS) activation causes osteopenia via beta(2)-adrenoceptor (beta(2)-AR) signaling. Here we show that female mice with chronic sympathetic hyperactivity owing to double knockout of adrenoceptors that negatively regulate norepinephrine release, alpha(2A)-AR and alpha(2C)-AR(alpha(2A)/alpha(2C)-ARKO), present an unexpected and generalized phenotype of high bone mass with decreased bone resorption and increased formation. In alpha(2A)/alpha(2C)-ARKO versus wild-type (WT) mice, micro-computed tomographic (mu CT) analysis showed increased, better connected, and more plate-shaped trabeculae in the femur and vertebra and increased cortical thickness in the vertebra, whereas biomechanical analysis showed increased tibial and femoral strength. Tibial mRNA expression of tartrate-resistant acid phosphatase (TRACP) and receptor activator of NF-kappa B (RANK), which are osteoclast-related factors, was lower in knockout (KO) mice. Plasma leptin and brain mRNA levels of cocaine amphetamine-regulated transcript (CART), which are factors that centrally affect bone turnover, and serum levels of estradiol were similar between mice strains. Tibial beta(2)-AR mRNA expression also was similar in KO and WT littermates, whereas alpha(2A)-, alpha(2B)- and alpha(2C)-AR mRNAs were detected in the tibia of WT mice and in osteoblast-like MC3T3-E1 cells. By immunohistochemistry, we detected alpha(2A)-, alpha(2B)-, alpha(2C)- and beta(2)-ARs in osteoblasts, osteoclasts, and chondrocytes of 18.5-day-old mouse fetuses and 35-day-old mice. Finally, we showed that isolated osteoclasts in culture are responsive to the selective alpha(2)-AR agonist clonidine and to the nonspecific alpha-AR antagonist phentolamine. These findings suggest that beta(2)-AR is not the single adrenoceptor involved in bone turnover regulation and show that alpha(2)-AR signaling also may mediate the SNS actions in the skeleton. (c) 2011 American Society for Bone and Mineral Research.
Resumo:
DO CARMO, E. C., T. FERNANDES, D. KOIKE, N. D. DA SILVA JR., K. C. MATTOS, K. T. ROSA, D. BARRETTI, S. F. S. MELO, R. B. WICHI, M. C. C. IRIGOYEN, and E. M. DE OLIVEIRA. Anabolic Steroid Associated to Physical Training Induces Deleterious Cardiac Effects. Med. Sci. Sports Exerc., Vol. 43, No. 10, pp. 1836-1848, 2011. Purpose: Cardiac aldosterone might be involved in the deleterious effects of nandrolone decanoate (ND) on the heart. Therefore, we investigated the involvement of cardiac aldosterone, by the pharmacological block of AT1 or mineralocorticoid receptors, on cardiac hypertrophy and fibrosis. Methods: Male Wistar rats were randomized into eight groups (n = 14 per group): Control (C), nandrolone decanoate (ND), trained (T), trained ND (TND), ND + losartan (ND + L), trained ND + losartan (TND + L), ND + spironolactone (ND + S), and trained ND + spironolactone (TND + S). ND (10 mg.kg(-1).wk(-1)) was administered during 10 wk of swimming training (five times per week). Losartan (20 mg.kg(-1).d(-1)) and spironolactone (10 mg.kg(-1).d(-1)) were administered in drinking water. Results: Cardiac hypertrophy was increased 10% by using ND and 17% by ND plus training (P < 0.05). In both groups, there was an increase in the collagen volumetric fraction (CVF) and cardiac collagen type III expression (P < 0.05). The ND treatment increased left ventricle-angiotensin-converting enzyme I activity, AT1 receptor expression, aldosterone synthase (CYP11B2), and 11-beta hydroxysteroid dehydrogenase 2 (11 beta-HSD2) gene expression and inflammatory markers, TGF beta and osteopontin. Both losartan and spironolactone inhibited the increase of CVF and collagen type III. In addition, both treatments inhibited the increase in left ventricle-angiotensin-converting enzyme I activity, CYP11B2, 11 beta-HSD2, TGF beta, and osteopontin induced by the ND treatment. Conclusions: We believe this is the first study to show the effects of ND on cardiac aldosterone. Our results suggest that these effects may be associated to TGF beta and osteopontin. Thus, we conclude that the cardiac aldosterone has an important role on the deleterious effects on the heart induced by ND.
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Microcystins (MC), a family of heptapeptide toxins produced by some genera of Cyanobacteria, have potent hepatotoxicity and tumor-promoting activity. Leukocyte infiltration in the liver was observed in MC-induced acute intoxication. Although the mechanisms of hepatotoxicity are still unclear, neutrophil infiltration in the liver may play an important role in triggering toxic injury and tumor development. The present study reports the effects of MC-LA, MC-YR and MC-LR (1 and 1000 nM) on human and rat neutrophils functions in vitro. Cell viability, DNA fragmentation, mitochondrial membrane depolarization and intracellular reactive oxygen species (ROS) levels were measured by flow cytometry. Extracellular ROS content was measured by lucigenin-amplified chemiluminescence, and cytokines were determined by ELISA. We found that these MC increased interleukin-8 (IL-8), cytokine-induced neutrophil chemoattractant-2 alpha beta (CINC-2 alpha beta) and extracellular ROS levels in human and rat neutrophils. Apart from neutrophil presence during the inflammatory process of MC-induced injury, our results suggest that hepatic neutrophil accumulation is further increased by MC-induced neutrophil-derived chemokine. (c) 2008 Elsevier Ltd. All rights reserved.
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Rare HFE variants have been shown to be associated with hereditary hemochromatosis (HH), an iron overload disease. The low frequency of the HFE p.C282Y mutation in HH-affected Brazilian patients may suggest that other HFE-related mutations may also be implicated in the pathogenesis of HH in this population. The main aim was to screen for new HFE mutations in Brazilian individuals with primary iron overload and to investigate their relationship with HH. Fifty Brazilian patients with primary iron overload (transferrin saturation >50% in females and 60% in males) were selected. Subsequent bidirectional sequencing for each HFE exon was performed. The effect of HFE mutations on protein structure were analyzed by molecular dynamics simulation and free binding energy calculations. p.C282Y in homozygosis or in heterozygosis with p.H63D were the most frequent genotypic combinations associated with HH in our sample population (present in 17 individuals, 34%). Thirty-six (72.0%) out of the 50 individuals presented at least one HFE mutation. The most frequent genotype associated with HH was the homozygous p.C282Y mutation (n = 11, 22.0%). One novel mutation (p.V256I) was indentified in heterozygosis with the p.H63D mutation. In silico modeling analysis of protein behavior indicated that the p.V256I mutation does not reduce the binding affinity between HFE and beta 2-microglobulin ((beta 2M) in the same way the p.C282Y mutation does compared with the native HFE protein. In conclusion, screening of HFE through direct sequencing, as compared to p.C282Y/p.H63D genotyping, was not able to increase the molecular diagnosis yield of HH. The novel p.V256I mutation could not be implicated in the molecular basis of the HH phenotype, although its role cannot be completely excluded in HH-phenotype development. Our molecular modeling analysis can help in the analysis of novel, previously undescribed, HFE mutations. (C) 2010 Elsevier Inc. All rights reserved.
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An enantioselective metal-mediated addition of allylic bromides to carbonyl compounds was achieved in the presence of the inexpensive and easily accessible carbohydrates saccharose and beta-cyclodextrin. The desired products were obtained in moderate to excellent yields and with up to 93% enantiomeric excess. (C) 2008 Elsevier Ltd. All rights reserved.
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A CE method is described for the enantioselective analysis of propranolol (Prop) and 4-hydroxypropranolol (4-OH-Prop) in liquid Czapek medium with application in the study of the enantioselective biotransformation of Prop by endophytic fungi. The electrophoretic conditions previously optimized were as follows: an uncoated fused-silica capillary, 4%w/v carboxymethyl-beta-CD in 25 mmol/L triethylamine/phosphoric acid (H(3)PO(4)) buffer at pH 9 as running electrolyte and 17 kV of voltage. UV detection was carried out at 208 nm. Liquid-liquid extraction using diethyl ether: ethyl acetate (1:1 v/v) as extractor solvent was employed for sample preparation. The calibration curves were linear over the concentration range of 0.25-10.0 mu g/mL for each 4-OH-Prop enantiomer and 0.10-10.0 mu g/mL for each Prop enantiomer (r >= 0.995). Within-day and between-day relative standard deviations and relative errors for precision and accuracy were lower than 15% for all the enantiomers. Finally, the validated method was used to evaluate Prop biotransformation in its mammalian metabolite 4-OH-Prop by some selected endophytic fungi. The screening of five strains of endophytic fungi was performed and all of them could biotransform Prop to some extent. Specifically, Glomerella cingulata (VA1) biotransformed 47.8% of (-)-(S)-Prop to (-)-(S)-4-OH-Prop with no formation of (+)-(R)4-OH-Prop in 72 h of incubation.
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An experimental design optimization (Box-Behnken design, BBD) was used to develop a CE method for the simultaneous resolution of propranolol (Prop) and 4-hydroxypropranolol enantiomers and acetaminophen (internal standard). The method was optimized using an uncoated fused silica capillary, carboxymethyl-beta-cyclodextrin (CM-beta-CD) as chiral selector and triethylamine/phosphoric acid buffer in alkaline conditions. A BBD for four factors was selected to observe the effects of buffer electrolyte concentration, pH, CM-beta-CD concentration and voltage on separation responses. Each factor was studied at three levels: high, central and low, and three center points were added. The buffer electrolyte concentration ranged from 25 to 75 mM, the pH ranged from 8 to 9, the CM-beta-CD concentration ranged from 3.5 to 4.5%w/v, and the applied run voltage ranged from 14 to 20 W. The responses evaluated were resolution and migration time for the last peak. The obtained responses were processed by Minitab (R) to evaluate the significance of the effects and to find the optimum analysis conditions. The best results were obtained using 4%w/v CM-beta-CD in 25 mM triethylamine/H(3)PO(4) buffer at pH 9 as running electrolyte and 17 kV of voltage. Resolution values of 1.98 and 1.95 were obtained for Prop and 4-hydroxypropranolol enantiomers, respectively. The total analysis time was around of 15 min. The BBD showed to be an adequate design for the development of a CE method, resulting in a rapid and efficient optimization of the pH and concentration of the buffer, cyclodextrin concentration and applied voltage.
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Inclusion complexes of Lippia sidoides essential oil and beta-cyclodextrin were obtained by slurry method and its solid powdered form was prepared using spray drying. The influence of the spray drying, as well as the different essential oil:beta-cyclodextrin ratio on the characteristics of the final product was investigated. With regard to the total oil retention 1:10 mass/mass ratio as optimal was found between the essential oil and beta-cyclodextrin. Thermoanalytical techniques (TG, EGD, TG-MS) were used to support the formation of inclusion complex and to examine their physicochemical properties after accelerated storage conditions. It may be assumed that the thermal properties of the complexes were influenced not only by the different essential oil/beta-cyclodextrin ratio but also by the storage conditions. In the aspect of their thermal stabilities, complex prepared with 1:10 m/m ratio (essential oil: beta-cyclodextrin) was the most stable one.
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Reaction of bis(ethane-1,2-diamine)copper(II) with acetaldehyde and nitromethane in methanol leads, stereoselectively, to the new macrocyclic complex (trans-5(R),7(R),12(S),14(S))-tetramethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecane)copper(II) perchlorate alpha-[CuL1](ClO4)(2) in good yield. Reduction of the nitro groups affords the hexaamine (L-2), which was crystallized as [H4L2](ClO4)(4) . 2H(2)O and characterized by an X-ray crystal structure study (monoclinic P2(1)/n, a = 9.763(2) Angstrom, b = 12.1988(7) Angstrom, c = 13.036(2) Angstrom, beta = 105.668(7)degrees, Z = 2) and complexed with Cu-II to produce the complex beta-[Cu(H2L2)](ClO4)(4) . 2H(2)O, which has also been characterized by X-ray crystallography (monoclinic P2(1)/n, a = 9.717(4) Angstrom, b = 12.174(2) Angstrom, c = 13.036(5) Angstrom, beta = 106.51(2)degrees, Z = 2). Reaction of alpha-[CuL1](2+) with either basic hydrogen peroxide or dilute nitrous acid leads to mild reduction of the nitro groups to afford the ketoxime L-3 as its N-based isomeric Cu-II complexes, trans-I [CuL3](ClO4)(2) and trans-II [Cu(L-3)Cl]Cl . 7H(2)O, the latter of which has been characterized structurally: triclinic, <P(1)over bar> a = 10.8441(5) Angstrom, b = 11.6632(9) Angstrom, c = 11.8723(9) Angstrom, alpha = 113.634(7)degrees, beta = 95.744(5), gamma = 94.851(5)degrees Z = 2. Variations in the configurations of the coordinated amines in [CuL1](2+), [CuL2](2+), and [CuL3](2+) have a profound effect on the spectroscopy and electrochemistry of their complexes.
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Intracellular amastigotes of the protozoan parasite Leishmania mexicana secrete a macromolecular proteophosphoglycan (aPPG) into the phagolysosome of their host cell, the mammalian macrophage. The structures of aPPG glycans were analyzed by a combination of high pH anion exchange high pressure liquid chromatography, gas chromatography-mass spectrometry, enzymatic digestions, electrospray-mass spectrometry as well as H-1 and P-31 NMR spectroscopy. Some glycans are identical to oligosaccharides known from Leishmania mexicana promastigote lipophosphoglycan and secreted acid phosphatase, However, the majority of the aPPG glycans represent amastigote stage-specific and novel structures. These include neutral glycans ([Glc beta(1-3)](1-2)Gal beta 1-4Man, Gal beta 1-3Gal beta 1-4Man, Gal beta 1-3Glc beta 1-3Gal beta 1-4Man), several monophosphorylated glycans containing the conserved phosphodisaccharide backbone (R-3-[PO4-6-Gal]beta 1-4Man) but carrying stage-specific modifications (R = Gal beta 1-, [Glc beta 1-3](1-2)Glc beta 1-), and monophosphorylated aPPG tri- and tetrasaccharides that are uniquely phosphorylated on the terminal hexose (PO4-6-Glc beta 1-3Gal beta 1-4Man, PO4-6-Glc beta 1-3Glc beta 1-3Gal beta 1-4Man, PO4-6-Gal beta 1-3Glc beta 1-3Gal beta 1-4Man), In addition aPPG contains highly unusual di- and triphosphorylated glycans whose major species are PO4-6-Glc beta 1-3Glc beta 1-3[PO4-6-Gal]beta 1-4Man, PO4-6-Gal beta 1-3Glc beta 1-3 [PO4-6-Gal]beta 1-4Man, PO4-6-GaL beta 1-3Glc beta 1-3Glc beta 1-3[PO4-6-Gal]beta 1-4Man, PO4-6-Glc beta 1-3[PO4-6-Glc]beta 1-3[PO4-6-Gal]beta 1-4Man, PO4-6Gal beta 1-3[PO4-6-Glc]beta 1-3Glc beta 1-3[PO4-6-Gal]beta 1-4Man, and PO4-6-Glc beta 1-3[PO4-6-Glc]beta 1-3Glc beta 1-3[PO4-6-Gal]beta 1-4Man. These glycans are linked together by the conserved phosphodiester R-Man alpha 1-PO4-6-Gal-R or the novel phosphodiester R-Man alpha 1-PO4-6-Glc-R and are connected to Ser(P) of the protein backbone most likely via the linkage R-Man alpha 1-PO4-Ser. The variety of stage-specific glycan structures in Leishmania mexicana aPPG suggests the presence of developmentally regulated amastigote glycosyltransferases which may be potential anti-parasite drug targets.
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To identify novel cytokine-related genes, we searched the set of 60,770 annotated RIKEN mouse cDNA clones (FANTOM2 clones), using keywords such as cytokine itself or cytokine names (such as interferon, interleukin, epidermal growth factor, fibroblast growth factor, and transforming growth factor). This search produced 108 known cytokines and cytokine-related products such as cytokine receptors, cytokine-associated genes, or their products (enhancers, accessory proteins, cytokine-induced genes). We found 15 clusters of FANTOM2 clones that are candidates for novel cytokine-related genes. These encoded products with strong sequence similarity to guanylate-binding protein (GBP-5), interleukin-1 receptor-associated kinase 2 (IRAK-2), interleukin 20 receptor alpha isoform 3, a member of the interferon-inducible proteins of the Ifi 200 cluster, four members of the membrane-associated family 1-8 of interferon-inducible proteins, one p27-like protein, and a hypothetical protein containing a Toll/Interleukin receptor domain. All four clones representing novel candidates of gene products from the family contain a novel highly conserved cross-species domain. Clones similar to growth factor-related products included transforming growth factor beta-inducible early growth response protein 2 (TIEG-2), TGFbeta-induced factor 2, integrin beta-like 1, latent TGF-binding protein 4S, and FGF receptor 4B. We performed a detailed sequence analysis of the candidate novel genes to elucidate their likely functional properties.
Resumo:
An extracellular glucoamylase produced by Paecilomyces variotii was purified using DEAE-cellulose ion exchange chromatography and Sephadex G-100 gel filtration. The purified protein migrated as a single band in 7% PAGE and 8% SDS-PAGE. The estimated molecular mass was 86.5 kDa (SDS-PAGE). Optima of temperature and pH were 55 degrees C and 5.0, respectively. In the absence of substrate the purified glucoamylase was stable for 1 h at 50 and 55 degrees C, with a t(50) of 45 min at 60 degrees C. The substrate contributed to protect the enzyme against thermal denaturation. The enzyme was mainly activated by manganese metal ions. The glucoamylase produced by P. variotii preferentially hydrolyzed amylopectin, glycogen and starch, and to a lesser extent malto-oligossacarides and amylose. Sucrose, p-nitrophenyl alpha-D-maltoside, methyl-alpha-D-glucopyranoside, pullulan, alpha- and beta-cyclodextrin, and trehalose were not hydrolyzed. After 24 h, the products of starch hydrolysis, analyzed by thin layer chromatography, showed only glucose. The circular dichroism spectrum showed a protein rich in alpha-helix. The sequence of amino acids of the purified enzyme VVTDSFR appears similar to glucoamylases purified from Talaromyces emersonii and with the precursor of the glucoamylase from Aspergillus oryzae. These results suggested the character of the enzyme studied as a glucoamylase (1,4-alpha-D-glucan glucohydrolase).
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Two N-based isomeric copper(II) complexes of the macrocycle trans-6,13-dimethyl-6,13-bis(dimethylamino)1,4,8,11-tetraazacyclotetradecane (L(3)) have been synthesized and characterised spectroscopically and structurally: alpha-[CuL(3)(OH2)(2)]Cl-2, monoclinic, space group C2/m, a = 12.908(4), b = 12.433(2), c = 7.330(2) Angstrom, beta = 105.87(2)degrees, Z = 2; beta-[CuL(3)(OClO3)(2)]. 2H(2)O, monoclinic, space group P2(1)/c, a = 9.708(3), b = 9.686(3), c = 14.202(4) Angstrom, beta = 106.17(1)degrees, Z = 2. The two isomers exhibit very similar co-ordination spheres but significantly different visible electronic maxima. This difference is attributed to an intramolecular N ... H contact between the pendant dimethylamino group and an adjacent secondary amine H atom.
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Background and purpose: We investigated the effect of nitric oxide synthase (NOS) inhibition on polymorphonuclear cell (PMN) influx in zymosan or lipopolysaccharide (LPS)-induced arthritis and peritonitis. Experimental approach: Wistar rats received intra-articular (i.art.) zymosan (30-1000 mu g) or LPS (1-10 mu g). Swiss C57/Bl6 mice genetically deficient in intercellular adhesion molecule-1 (ICAM-1(-/-)) or in beta(2)-integrin (beta(2)-integrin(-/-)) received zymosan either i.art. or i.p. PMN counts, leukotriene B(4) (LTB(4)), tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) levels were measured in joint and peritoneal exudates. Groups received the NOS inhibitors N(G)-nitro-L-arginine methyl ester (LN), nitro-L-arginine, N-[3-(aminomemethyl) benzyl] acetamide or aminoguanidine, prior to zymosan or LPS, given i.p. or s.c. in the arthritis and peritonitis experiments respectively. A group of rats received LN locally (i.art. or i.p.), 30 min prior to 1 mg zymosan i.art. Key results: Systemic or local NOS inhibition significantly prevented PMN migration in arthritis while increasing it in peritonitis, regardless of stimuli, concentration of NOS inhibitors and species. NOS inhibition did not alter TNF-alpha and IL-10 but decreased LTB(4) in zymosan-induced arthritis. LN administration significantly inhibited PMN influx into the joints of ICAM-1(-/-) and beta(2)-integrin(-/-) mice with zymosan-arthritis, while not altering PMN influx into the peritoneum of mice with zymosan-peritonitis. Conclusions and implications: Nitric oxide has a dual modulatory role on PMN influx into joint and peritoneal cavities that is stimulus-and species-independent. Differences in local release of LTB(4) and in expression of ICAM-1 and beta(2)-integrin account for this dual role of NO on PMN migration.