971 resultados para 1-HEXYL-4-ETHYLOCTYL ISOPROPYLPHOSPHONIC ACID
Resumo:
The physiological and molecular processes controlling zygotic and somatic embryo development in angiosperms are mediated by a hierarchically organized program of gene expression. Despite the overwhelming information available about the molecular control of the embryogenic processes in angiosperms, little is known about these processes in gymnosperms. Here we describe the cloning and characterization of the expression pattern of the Araucaria angustifolia putative homolog of a SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) gene family member, designated as AaSERK1. The Araucaria AaSERK1 gene encodes a leucine-rich repeat receptor-like kinase showing significant similarity to angiosperm homologs of SERK1, known to be involved in early somatic and zygotic embryogenesis. Accordingly, RT-PCR results showed that AaSERK1 is preferentially expressed in Araucaria embryogenic cell cultures. Additionally, in situ hybridization results showed that AaSERK1 transcripts initially accumulate in groups of cells at the periphery of the embryogenic calli and then are restricted to the developing embryo proper. Our results indicate that AaSERK1 might have a role during somatic embryogenesis in Araucaria, suggesting a potentially conserved mechanism, involving SERK-related leucine-rich repeat receptor-like kinases, in the embryogenic processes among all seed plants.
Resumo:
We investigated whether interleukin-4 (IL-4) is present and capable of reducing inflammatory changes seen in ifosfamide-induced hemorrhagic cystitis. Male Swiss mice were treated with saline or ifosfamide alone or ifosfamide with the classical protocol with mesna and analyzed by changes in bladder wet weight (BWW), macroscopic and microscopic parameters, exudate, and hemoglobin quantification. In other groups, IL-4 was administered intraperitoneally 1 h before ifosfamide. In other experimental groups, C57BL/6 WT (wild type) and C57BL/6 WT IL-4 (-/-) knockout animals were treated with ifosfamide and analyzed for changes in BWW. Quantification of bladder IL-4 protein by ELISA in control, ifosfamide-, and mesna-treated groups was performed. Immunohistochemistry to tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) as well as protein identification by Western blot assay for inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was carried out on ifosfamide- and IL-4-treated animals. In other experimental groups, antiserum against IL-4 was given 30 min before ifosfamide. In IL-4-treated animals, the severity of hemorrhagic cystitis was significantly milder than in animals treated with ifosfamide only, an effect that was reverted with serum anti-IL-4. Moreover, knockout animals for IL-4 (-/-) exhibit a worse degree of inflammation when compared to C57BL/6 wild type. Exogenous IL-4 also attenuated TNF-alpha, IL-1 beta, iNOS, and COX-2 expressions in ifosfamide-treated bladders. IL-4, an anti-inflammatory cytokine, attenuates the inflammation seen in ifosfamide-induced hemorrhagic cystitis.
Resumo:
Brazilian pine (Araucaria angustifolia (Bert) O. Ktze) is the only native conifer species with economic importance in Brazil. Recently, due to intensive exploitation Brazilian pine was included in the official list of endangered Brazilian plants, under the "vulnerable" category. Biotechnology tools like somatic embryogenesis (SE) are potentially useful for mass clonal propagation and ex situ conservation strategies of commercial and endangered plant species. In spite of that, numerous obstacles still hamper the full application of SE technology for a wider range of species, including Brazilian pine. To enhance somatic embryogenesis in Brazilian pine and to gain a better understanding of the molecular events associated with somatic embryo development, we analyzed the steady-state transcript levels of genes known to regulate somatic embryogenesis using semiquantitative reverse transcription polymerase chain reaction (sqRT-PCR). These genes included Argonaute (AaAGO), Cup-shaped cotyledon1 (AaCUC), wushel-related WOX (AaWOX), a S-locus lectin protein kinase (AaLecK), Scarecrow- like (AaSCR), Vicilin 7S (AaVIC), Leafy Cotyledon 1 (AaLEC), and a Reversible glycosylated polypeptide (AaRGP). Expression patterns of these selected genes were investigated in embryogenic cultures undergoing different stages of embryogenesis, and all the way to maturation. Up-regulation of AaAGO, AaCUC, AaWOX, AaLecK, and AaVIC was observed during transition of somatic embryos from stage I to stage II. During the maintenance phase of somatic embryogenesis, expression of AaAGO and AaSCR, but not AaRPG and AaLEC genes was influenced by presence/ absence of plant growth regulators, both auxins and cytokinins. The results presented here provide new insights on the molecular mechanisms responsible for somatic embryo formation, and how selected genes may be used as molecular markers for Brazilian pine embryogenesis.
Resumo:
Evidences have suggested that the endocannabinoid system is overactive in obesity, resulting in enhanced endocannabinoid levels in both circulation and visceral adipose tissue. The blockade of cannabinoid receptor type 1 (CB1) has been proposed for the treatment of obesity. Besides loss of body weight, CB1 antagonism improves insulin sensitivity, in which the glucose transporter type 4 (GLUT4) plays a key role. The aim of this study was to investigate the modulation of GLUT4-encoded gene (Slc2a4 gene) expression by CB1 receptor. For this, 3T3-L1 adipocytes were incubated in the presence of a highly selective CB1 receptor agonist (1 mu M arachidonyl-2'-chloroethylamide) and/or a CB1 receptor antagonist/inverse agonist (0.1, 0.5, or 1 mu M AM251, 1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide). After acute (2 and 4 h) and chronic (24 h) treatments, cells were harvested to evaluate: i) Slc2a4, Cnr1 (CB1 receptor-encoded gene), and Srebf1 type a (SREBP-1a type-encoded gene) mRNAs (real-time PCR); ii) GLUT4 protein (western blotting); and iii) binding activity of nuclear factor (NF)-kappa B and sterol regulatory element-binding protein (SREBP)-1 specifically in the promoter of Slc2a4 gene (electrophoretic mobility shift assay). Results revealed that both acute and chronic CB1 receptor antagonism greatly increased (similar to 2.5-fold) Slc2a4 mRNA and protein content. Additionally, CB1-induced upregulation of Slc2a4 was accompanied by decreased binding activity of NF-kappa B at 2 and 24 h, and by increased binding activity of the SREBP-1 at 24 h. In conclusion, these findings reveal that the blockade of CB1 receptor markedly increases Slc2a4/GLUT4 expression in adipocytes, a feature that involves NF-kappa B and SREBP-1 transcriptional regulation. Journal of Molecular Endocrinology (2012) 49, 97-106
Resumo:
There is growing interest in cellulose nanofibres from renewable sources for several industrial applications. However, there is a lack of information about one of the most abundant cellulose pulps: bleached Eucalyptus kraft pulp. The objective of the present work was to obtain Eucalyptus cellulose micro/nanofibres by three different processes, namely: refining, sonication and acid hydrolysis of the cellulose pulp. The refining was limited by the low efficiency of isolated nanofibrils, while sonication was more effective for this purpose. However, the latter process occurred at the expense of considerable damage to the cellulose structure. The whiskers obtained by acid hydrolysis resulted in nanostructures with lower diameter and length, and high crystallinity. Increasing hydrolysis reaction time led to narrower and shorter whiskers, but increased the crystallinity index. The present work contributes to the different widespread methods used for the production of micro/nanofibres for different applications. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
The studies of niobium after electrochemical polishing EP in sulfuric-methanesulfonic acid mixture were performed. The NbOx/Nb surface was studied by SEM/EDX and XPS methods to find out the chemical composition of the oxygen-induced structures. Specifically the XPS results obtained after EP treatment indicate prevailing part of oxygen with niobium oxides on the sample surface. In order to correctly interpret these structures the photoelectron spectra of main niobium oxides were analyzed, and the spectra of internal Nb 3d and O 1s electronic states and valence band spectra were measured for them. (C) 2012 Elsevier B. V. All rights reserved.
Resumo:
We present STAR measurements of azimuthal anisotropy by means of the two- and four-particle cumulants nu(2) (nu(2){2} and nu(2){4}) for Au + Au and Cu + Cu collisions at center-of-mass energies root S-NN = 62.4 and 200 GeV. The difference between nu(2){2}(2) and nu(2){4}(2) is related to nu(2) fluctuations (sigma(nu 2)) and nonflow (delta(2)). We present an upper limit to sigma(nu 2)/nu 2. Following the assumption that eccentricity fluctuations sigma(epsilon) dominate nu(2) fluctuations nu(2)/sigma nu(2) approximate to epsilon/sigma epsilon we deduce the nonflow implied for several models of eccentricity fluctuations that would be required for consistency with nu(2){2} and nu(2){4}. We also present results on the ratio of nu(2) to eccentricity.
Resumo:
N-4-Phenyl 2-acetylpyridine thiosemicarbazone (H2Ac4Ph; N-(phenyl)-2-(1-(pyridin-2-yl)ethylidene) hydrazinecarbothioamide) and its N-4-ortho-, -meta- and -para-fluorophenyl (H2Ac4oFPh, H2Ac4mFPh, H2Ac4pFPh), N-4-ortho-, -meta- and -para-chlorophenyl (H2Ac4oClPh, H2Ac4mClPh, H2Ac4pClPh), N-4-ortho-, -meta- and -para-iodophenyl (H2Ac4oIPh, H2Ac4mIPh, H2Ac4pIPh) and N-4-ortho-, -meta- and -para-nitrophenyl (H2Ac4oNO(2)Ph, H2Ac4mNO(2)Ph, H2Ac4pNO(2)Ph) derivatives were assayed for their cytotoxicity against human malignant breast (MCF-7) and glioma (T98G and U87) cells. The compounds were highly cytotoxic against the three cell lineages (IC50: MCF-7, 52-0.16 nM; T98G, 140-1.0 nM; U87, 160-1.4 nM). All tested thiosemicarbazones were more cytotoxic than etoposide and did not present any haemolytic activity at up to 10(-5) M. The compounds were able to induce programmed cell death. H2Ac4pClPh partially inhibited tubulin assembly at high concentrations and induced cellular microtubule disorganization. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
BACKGROUND: Ghrelin is a gastrointestinal peptide hormone (a 28-amino acid peptide) produced primarily by X/A cells in the oxyntic glands of the stomach fundus and cells lining the duodenum cavern. It suppresses insulin secretion and action and commands a significant role in regulating food intake. The aim of the present study was to show that modified laparoscopic sleeve gastrectomy (MLSG), in which a significant part of the gastric fundus and body of the stomach is removed up to 1 inch from the pylorus vein, may contribute to decreasing circulating ghrelin levels. METHODS: A study population consisting of 150 individuals was monitored after undergoing a MLSG, with individuals chosen based on a documented history of diabetes mellitus type 2 and metabolic syndrome, clinical results determining a body mass index (BMI) of 35 to 60 kg/m(2), peptide C level greater than 1, negative anti-glutamic acid decarboxylase, negative anti-insulin, and confirmed stability of drug/insulin treatment and glycosylated hemoglobin greater than 6.5% for at least 24 and 3 months, respectively, before enrollment. RESULTS: Twenty-four months after surgery, 150 patients (86.6%) presented with normal glycemic levels between 77 and 99 mg/dL. All patients improved average serum insulin levels by 9 mU/L and average glycosylated hemoglobin levels by 5.1% (normal range, 4%-6%). All patients tested negative for Helicobacter pylori and stopped using insulin, with 3 patients prescribed twice-daily use of an oral hypoglycemiant. In 14% of cases, patients experienced partial hair loss with low serum zinc levels and were prescribed oral zinc reposition and topical hair stimulants. The average weight loss recorded was 44.6% for patients with a BMI less than 45 kg/m(2) and 58% for patients with a BMI greater than 50 kg/m(2). CONCLUSIONS: The MLSG is a safe procedure with a low morbidity rate (2.7%) (4 cases of fistula and 2 of bleeding) and no surgical mortality in this study. This surgery can promote control of diabetes mellitus type 2 and aid the treatment of exogenous overweight and morbidly obese individuals. The results of this study show that only through resection of the ghrelin-producing gastric area can most obesity cases and diabetes type II conditions be reverted to nonobese and controlled diabetes. (c) 2012 Elsevier Inc. All rights reserved.
Resumo:
Industrial production of semi-synthetic cephalosporins by Penicillium chrysogenum requires supplementation of the growth media with the side-chain precursor adipic acid. In glucose-limited chemostat cultures of P. chrysogenum, up to 88% of the consumed adipic acid was not recovered in cephalosporinrelated products, but used as an additional carbon and energy source for growth. This low efficiency of side-chain precursor incorporation provides an economic incentive for studying and engineering the metabolism of adipic acid in P. cluysogenum. Chemostat-based transcriptome analysis in the presence and absence of adipic acid confirmed that adipic acid metabolism in this fungus occurs via beta-oxidation. A set of 52 adipate-responsive genes included six putative genes for acyl-CoA oxidases and dehydrogenases, enzymes responsible for the first step of beta-oxidation. Subcellular localization of the differentially expressed acyl-CoA oxidases and dehydrogenases revealed that the oxidases were exclusively targeted to peroxisomes, while the dehydrogenases were found either in peroxisomes or in mitochondria. Deletion of the genes encoding the peroxisomal acyl-CoA oxidase Pc20g01800 and the mitochondrial acyl-CoA dehydrogenase Pc20g07920 resulted in a 1.6- and 3.7-fold increase in the production of the semi-synthetic cephalosporin intermediate adipoyl-6-APA, respectively. The deletion strains also showed reduced adipate consumption compared to the reference strain, indicating that engineering of the first step of beta-oxidation successfully redirected a larger fraction of adipic acid towards cephalosporin biosynthesis. (C) 2012 Elsevier Inc. All rights reserved.
Resumo:
A dihydrate pseudopolymorph of bis(2,4-dihydroxyphenyl)methanone, C13H10O5 center dot 2H2O, (I), was obtained during polymorphism screening of hydroxybenzophenone derivatives. This structure, in which the molecule sits on a twofold axis, was compared with the known anhydrous form of (I) [Schlemper (1982). Acta Cryst. B38, 554559]. The role of water in the crystal assembly was established on the basis of the known monohydrate pseudopolymorph of 3,4-dihydroxybenzophenone [Landre, Souza, Correa, Martins & Doriguetto (2010). Acta Cryst. C66, o463o465].
Resumo:
Emerging resistance to chloroquine (CQ) poses a major challenge for Plasmodium vivax malaria control, and nucleotide substitutions and copy number variation in the P. vivax multidrug resistance 1 (pvmdr-1) locus, which encodes a digestive vacuole membrane transporter, may modulate this phenotype. We describe patterns of genetic variation in pvmdr-1 alleles from Acre and Amazonas in northwestern Brazil, and compare then with those reported in other malaria-endemic regions. The pvmdr-1 mutation Y976F, which is associated with CQ resistance in Southeast Asia and Oceania, remains rare in northwestern Brazil (1.8%) and its prevalence mirrors that of CO resistance worldwide. Gene amplification of pvmdr-1, which is associated with mefloquine resistance but increased susceptibility to CO, remains relatively rare in northwestern Brazil (0.9%) and globally (< 4%), but became common (> 10%) in Tak Province, Thailand, possibly because of drug-mediated selection. The global database we have assembled provides a baseline for further studies of genetic variation in pvmdr-1 and drug resistance in P. vivax malaria.
Resumo:
This study correlated the composition of the spoilage bacterial flora with the main gaseous and volatile organic compounds (VOCs) found in the package headspace of spoiled, chilled, vacuum-packed meat. Fifteen chilled, vacuum-packed beef samples, suffering from blown pack spoilage, were studied using 16S rRNA clone sequencing. More than 50% of the bacteria were identified as lactic acid bacteria (LAB), followed by clostridia and enterobacteria. Fifty-one volatile compounds were detected in the spoiled samples. Although the major spoilage compounds were identified as alcohols and aldehydes, CO2 was identified as the major gas in the spoiled samples by headspace technique. Different species of bacteria contribute to different volatile compounds during meat spoilage. LAB played an important role in blown pack deterioration of the Brazilian beef studied.
Resumo:
Conflicting findings about the association between leprosy and TLR1 variants N248S and I602S have been reported. Here, we performed case-control and family based studies, followed by replication in 2 case-control populations from Brazil, involving 3162 individuals. Results indicated an association between TLR1 248S and leprosy in the case-control study (SS genotype odds ratio [OR], 1.81; P = .004) and the family based study (z = 2.02; P = .05). This association was consistently replicated in other populations (combined OR, 1.51; P < .001), corroborating the finding that 248S is a susceptibility factor for leprosy. Additionally, we demonstrated that peripheral blood mononuclear cells (PBMCs) carrying 248S produce a lower tumor necrosis factor/interleukin-10 ratio when stimulated with Mycobacterium leprae but not with lipopolysaccharide or PAM3cysK4. The same effect was observed after infection of PBMCs with the Moreau strain of bacillus Calmette-Guerin but not after infection with other strains. Finally, molecular dynamics simulations indicated that the Toll-like receptor 1 structure containing 248S amino acid is different from the structure containing 248N. Our results suggest that TLR1 248S is associated with an increased risk for leprosy, consistent with its hypoimmune regulatory function.
Resumo:
Background Oxidative stress is recognized as a major pathogenic factor of cellular damage caused by hyperglycemia. NOX/NADPH oxidases generate reactive oxygen species and NOX1, NOX2 and NOX4 isoforms are expressed in kidney and require association with subunit p22phox (encoded by the CYBA gene). Increased expression of p22phox was described in animal models of diabetic nephropathy. In the opposite direction, glutathione is one of the main endogenous antioxidants whose plasmatic concentrations were reported to be reduced in diabetes patients. The aim of the present investigation was to test whether functional single nucleotide polymorphisms (SNPs) in genes involved in the generation of NADPH-dependent O2•- (-675 T → A in CYBA, unregistered) and in glutathione metabolism (-129 C → T in GCLC [rs17883901] and -65 T → C in GPX3 [rs8177412]) confer susceptibility to renal disease in type 1 diabetes patients. Methods 401 patients were sorted into two groups according to the presence (n = 104) or absence (n = 196) of overt diabetic nephropathy or according to glomerular filtration rate (GFR) estimated by Modification of Diet in Renal Disease (MDRD) equation: ≥ 60 mL (n = 265) or < 60 mL/min/1.73 m2 (n = 136) and were genotyped. Results No differences were found in the frequency of genotypes between diabetic and non-diabetic subjects. The frequency of GFR < 60 mL/min was significantly lower in the group of patients carrying CYBA genotypes T/A+A/A (18.7%) than in the group carrying the T/T genotype (35.3%) (P = 0.0143) and the frequency of GFR < 60 mL/min was significantly higher in the group of patients carrying GCLC genotypes C/T+T/T (47.1%) than in the group carrying the C/C genotype (31.1%) (p = 0.0082). Logistic regression analysis identified the presence of at least one A allele of the CYBA SNP as an independent protection factor against decreased GFR (OR = 0.38, CI95% 0.14-0.88, p = 0.0354) and the presence of at least one T allele of the GCLC rs17883901 SNP as an independent risk factor for decreased GFR (OR = 2.40, CI95% 1.27-4.56, p = 0.0068). Conclusions The functional SNPs CYBA -675 T → A and GCLC rs17883901, probably associated with cellular redox imbalances, modulate the risk for renal disease in the studied population of type 1 diabetes patients and require validation in additional cohorts.