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991.
Bruna Comparsi Daiane F. Meinerz Jeferson L. Franco Thaís Posser Alessandro de Souza Prestes Sílvio Terra Stefanello Danúbia B. dos Santos Caroline Wagner Marcelo Farina Michael Aschner Alcir L. Dafre Jo?o B. T. Rocha 《Molecular and cellular biochemistry》2012,370(1-2):173-182
In this study, we investigated the effect of diphenyl ditelluride (PhTe)2 administration (10 and 50?μmol/kg) on adult mouse behavioral performance as well as several parameters of oxidative stress in the brain and liver. Adult mice were injected with (PhTe)2 or canola oil subcutaneously (s.c.) daily for 7?days. Results demonstrated that (PhTe)2 induced prominent signs of toxicity (body weight loss), behavioral alterations and increased in lipid peroxidation in brain. 50?μmol/kg (PhTe)2 inhibited blood δ-aminolevulinic acid dehydratase (δ-ALA-D), a redox sensitive enzyme. (PhTe)2 caused an increase in cerebral non-protein thiol (NPSH) and protein thiol (PSH) groups. In the liver, 50?μmol/kg (PhTe)2 decreased NPSH, but did not alter the content of protein thiol groups. (PhTe)2 decreased cerebral antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), and thioredoxin reductase (TrxR). In liver, (PhTe)2 increase SOD and GR and decreased GPx activity. Results obtained herein suggest that the brain was more susceptible to oxidative stress induced by (PhTe)2 than the liver. Furthermore, we have demonstrated for the first time that TrxR is an in vivo target for (PhTe)2. Combined, these results highlight a novel molecular mechanism involved in the toxicity of (PhTe)2. In particular the inhibition of important selenoenzymes (TrxR and GPx) seems to be involved in the neurotoxicity associated with (PhTe)2 exposure in adult mice. 相似文献
992.
dos Reis SP Tavares Lde S Costa Cde N Brígida AB de Souza CR 《Molecular biology reports》2012,39(6):6513-6519
Cassava (Manihot esculenta Crantz) is one of the world’s most important food crops. It is cultivated mainly in developing countries of tropics, since
its root is a major source of calories for low-income people due to its high productivity and resistance to many abiotic and
biotic factors. A previous study has identified a partial cDNA sequence coding for a putative RING zinc finger in cassava
storage root. The RING zinc finger protein is a specialized type of zinc finger protein found in many organisms. Here, we
isolated the full-length cDNA sequence coding for M. esculenta RZF (MeRZF) protein by a combination of 5′ and 3′ RACE assays. BLAST analysis showed that its deduced amino acid sequence
has a high level of similarity to plant proteins of RZF family. MeRZF protein contains a signature sequence motif for a RING
zinc finger at its C-terminal region. In addition, this protein showed a histidine residue at the fifth coordination site,
likely belonging to the RING-H2 subgroup, as confirmed by our phylogenetic analysis. There is also a transmembrane domain
in its N-terminal region. Finally, semi-quantitative RT-PCR assays showed that MeRZF expression is increased in detached leaves
treated with sodium chloride. Here, we report the first evidence of a RING zinc finger gene of cassava showing potential role
in response to salt stress. 相似文献
993.
Hugo Sousa Alexandra M. Santos Raquel Catarino Daniela Pinto José Moutinho Paulo Canedo José Carlos Machado Rui Medeiros 《Molecular biology reports》2012,39(12):10837-10842
Human Papillomavirus infection is considered as the main etiological factor of cervical cancer (ICC), although, the role of host genetic factors in ICC susceptibility has been increasing. Immunological response is crucial for the prevention of viral associated diseases. Interleukin 1 receptor antagonist (IL-1RN) is considered to be an important regulator of host immunity and several studies have shown a potential role of a 86?bp VNTR polymorphism within intron 2 of the IL-1RN gene in host immune response variability. We investigated the role of this polymorphism in cervical cancer development in Portugal with a case–control study developed with peripheral blood samples from 196 healthy women and 340 women with cervical lesions from the Northern Region of Portugal. We observed that IL-1RN Allele 2 homozygosis was significantly higher in cases than in controls. In fact, IL-1RN A2*A2 homozygous revealed to be associated with an increased risk of HSIL?+?ICC (OR?=?1.90; 95?% IC 1.13–3.21; p?=?0.015). Furthermore, we also observed that median age of onset of HSIL?+?ICC was significantly different (46.0 vs 52.0) in IL-1RN A2*A2 homozygous comparing to non-A2*A2 (p?=?0.028). Our results indicated that IL-1RN A2 allele is associated with an increased susceptibility to cervical cancer development, probably by increasing predisposition to shorter immune responses. 相似文献
994.
de Lima AP Pereira Fde C Vilanova-Costa CA Soares JR Pereira LC Porto HK Pavanin LA Dos Santos WB Silveira-Lacerda Ede P 《Biological trace element research》2012,147(1-3):8-15
Lung cancer is one of the leading causes of death in the world, and non-small cell lung carcinoma (NSCLC) accounts for approximately 75-85% of all lung cancers. In the present work, we studied the cytotoxic activity, cell cycle arrest and induction apoptosis of the compound cis-(dichloro)tetramineruthenium(III) chloride {cis-[RuCl(2)(NH(3))(4)]Cl} in human lung carcinoma tumor cell line A549. The results of MTT and trypan blue assays showed that cis-[RuCl(2)(NH(3))(4)]Cl causes reduction in the viability of A549 cells when treating with 95 and 383 μM of the compound for 48 and 72 h. Lower concentrations of the compound (19, 3.8 and 0.38 μM), however, only slightly affected cell viability. The IC(50) value for the compound was about 383 μM. Survival analysis of the A549 cells after treatment with ruthenium(III) compound using long term clonogenic assay showed that it reduced colony formation ability at concentrations of 0.38 and 3.8 μM, and at concentrations of 95 and 383 μM no colonies were observed. Cell cycle analysis showed that compound ruthenium led to an accumulation of A549 cells in S phase and increased in the sub-G1 peak. In addition, cis-(dichloro)tetramineruthenium(III) chloride treatment induced apoptosis, as observed by the increased numbers of annexin V-positive cells and increased messenger RNA expression of caspase-3. 相似文献
995.
996.
Acosta-Avalos D Dos Santos Azevedo LM Salama Andrade T Lins de Barros H 《European biophysics journal : EBJ》2012,41(5):405-413
Candidatus Magnetoglobus multicellularis (CMm) is a multicellular organism in which each constituent cell is a magnetotactic bacterium.
It has been observed that disaggregation of this organism provokes the death of the individual cells. The observed flagellar
movement of the CMm indicates that the constituent cells move in a coordinated way, indicating a strong correlation between
them and showing that this aggregate could be considered as an individual. As every constituent cell is a magnetotactic bacterium,
every cell contributes with a magnetic moment vector to the resultant magnetic moment of the CMm organism that can be calculated
through the vectorial sum of all the constituent magnetic moments. Scanning electron microscopy images of CMm organisms have
shown that the constituent cells are distributed on a helix convoluted on a spherical surface. To analyze the magnetic properties
of the distribution of magnetic moments on this curve, we calculated the magnetic energy numerically as well as the vectorial
sum of the magnetic moment distribution as a function of the number of cells, the sphere radius and the number of spiral loops.
This distribution proposes a magnetic organization not seen in any other living organism and shows that minimum energy configurations
of magnetic moments are in spherical meridian chains, perpendicular to the helix turns. We observed that CMm has a high theoretical
degree of magnetic optimization, showing that its geometrical structure is important to the magnetic response. Our results
indicate that the helical structure must have magnetic significance. 相似文献
997.
Santos CR Paiva JH Sforça ML Neves JL Navarro RZ Cota J Akao PK Hoffmam ZB Meza AN Smetana JH Nogueira ML Polikarpov I Xavier-Neto J Squina FM Ward RJ Ruller R Zeri AC Murakami MT 《The Biochemical journal》2012,441(1):95-104
Cellulases participate in a number of biological events, such as plant cell wall remodelling, nematode parasitism and microbial carbon uptake. Their ability to depolymerize crystalline cellulose is of great biotechnological interest for environmentally compatible production of fuels from lignocellulosic biomass. However, industrial use of cellulases is somewhat limited by both their low catalytic efficiency and stability. In the present study, we conducted a detailed functional and structural characterization of the thermostable BsCel5A (Bacillus subtilis cellulase 5A), which consists of a GH5 (glycoside hydrolase 5) catalytic domain fused to a CBM3 (family 3 carbohydrate-binding module). NMR structural analysis revealed that the Bacillus CBM3 represents a new subfamily, which lacks the classical calcium-binding motif, and variations in NMR frequencies in the presence of cellopentaose showed the importance of polar residues in the carbohydrate interaction. Together with the catalytic domain, the CBM3 forms a large planar surface for cellulose recognition, which conducts the substrate in a proper conformation to the active site and increases enzymatic efficiency. Notably, the manganese ion was demonstrated to have a hyper-stabilizing effect on BsCel5A, and by using deletion constructs and X-ray crystallography we determined that this effect maps to a negatively charged motif located at the opposite face of the catalytic site. 相似文献
998.
M. Quara de Carvalho Santos J. R. Gonzaga Lemos C. do Nascimento Pereira A. Teixeira de Oliveira M. Tavares‐Dias J. L. Marcon 《Zeitschrift fur angewandte Ichthyologie》2012,28(1):148-149
The present work reports the length–weight relationships (LWR) for four ornamental fish species from the middle Negro River basin, Amazonas, Brazil. The r2 value ranged from 0.810 to 0.941 and values of b varied from 2.346 to 3.442. These results represent the first reference on LWR for all four species, based on FishBase. 相似文献
999.
Vinolo MA Rodrigues HG Festuccia WT Crisma AR Alves VS Martins AR Amaral CL Fiamoncini J Hirabara SM Sato FT Fock RA Malheiros G dos Santos MF Curi R 《American journal of physiology. Endocrinology and metabolism》2012,303(2):E272-E282
The aim of this study was to investigate whether treatment with tributyrin (Tb; a butyrate prodrug) results in protection against diet-induced obesity and associated insulin resistance. C57BL/6 male mice fed a standard chow or high-fat diet were treated with Tb (2 g/kg body wt, 10 wk) and evaluated for glucose homeostasis, plasma lipid profile, and inflammatory status. Tb protected mice against obesity and obesity-associated insulin resistance and dyslipidemia without food consumption being affected. Tb attenuated the production of TNFα and IL-1β by peritoneal macrophages and their expression in adipose tissue. Furthermore, in the adipose tissue, Tb reduced the expression of MCP-1 and infiltration by leukocytes and restored the production of adiponectin. These effects were associated with a partial reversion of hepatic steatosis, reduction in liver and skeletal muscle content of phosphorylated JNK, and an improvement in muscle insulin-stimulated glucose uptake and Akt signaling. Although part of the beneficial effects of Tb are likely to be secondary to the reduction in body weight, we also found direct protective actions of butyrate reducing TNFα production after LPS injection and in vitro by LPS- or palmitic acid-stimulated macrophages and attenuating lipolysis in vitro and in vivo. The results, reported herein, suggest that Tb may be useful for the treatment and prevention of obesity-related metabolic disorders. 相似文献
1000.
Ramírez-Carreto S Quintero-Hernández V Jiménez-Vargas JM Corzo G Possani LD Becerril B Ortiz E 《Peptides》2012,34(2):290-295
From the cDNA libraries made from the venom glands of two scorpions belonging to the Vaejovidae family, four different putative non disulfide-bridged antimicrobial peptides were identified: VmCT1 and VmCT2 from Vaejovis mexicanus smithi plus VsCT1 and VsCT2 from Vaejovis subcristatus. These short peptides (with only 13 amino acid residues each) share important amino acid sequence similarities among themselves and with other reported antimicrobial peptides, but their biological activities vary dramatically. This communication reports the cloning, chemical synthesis and characterization of these peptides. Two peptides, VmCT1 and VmCT2 showed broad-spectrum antibacterial activity with minimum inhibitory concentrations MICs in the range of 5-25 μM and 10-20 μM respectively, whereas their hemolytic activity at these concentrations was low. Structure-function relationships that might determine the differences in activities are discussed. 相似文献