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211.
Paulo A.S. Mourão Suely Rozenfeld J. Laredo Carl P. Dietrich 《Biochimica et Biophysica Acta (BBA)/General Subjects》1976,428(1):19-26
The relative contents of chondroitin 4- and 6-sulfates in cartilages of different human bones are reported. Articular and vertebral body cartilages contain almost exclusively chondroitin 6-sulfate, whereas growth and subarticular cartilages contain nearly equal amounts of chondroitin 4-sulfate and chondroitin 6-sulfate. Adult cartilages, where the calcification process is complete, contain only chondroitin 6-sulfate. These results suggest that chondroitin 4-sulfate may be an important component for the calcification process, whereas chondroitin 6-sulfate seems to be related to the integrity of the articular surfaces. A chemical defect of chondroitin 6-sulfate in a new mucopolysaccharidosis, characterized by platyspondyly and irregularities of articular surfaces, is in agreement with these results. 相似文献
212.
Naiara Stefanello Roberta Schmatz Luciane Belmonte Pereira Maribel A. Rubin João Batista Teixeira da Rocha Graziela Facco Maria Ester Pereira Cinthia Melazzo de Andrade Mazzanti Sabina Passamonti Marília Valvassori Rodrigues Fabiano Barbosa Carvalho Michelle Melgarejo da Rosa Jessie Martins Gutierres Andréia Machado Cardoso Vera Maria Morsch Maria Rosa Chitolina Schetinger 《Molecular and cellular biochemistry》2014,385(1-2):277-286
Mesenchymal stem cells (MSCs) represent a potential therapeutic target for glioma. We determined the molecular mechanism of inhibitory effect of human umbilical cord-derived MSCs (hUC-MSCs) on the growth of C6 glioma cells. We demonstrated that hUC-MSCs inhibited C6 cell growth and modulated the cell cycle to G0/G1 phase. The expression of β-catenin and c-Myc was downregulated in C6 cells by conditioned media from hUC-MSCs, and the levels of secreted DKK1 were positively correlated with concentrations of hUCMSCs-CM. The inhibitory effect of hUC-MSCs on C6 cell proliferation was enhanced as the concentration of DKK1 in hUCMSCs-CM increased. When DKK1 was neutralized by anti-DKK1 antibody, the inhibitory effect of hUC-MSCs on C6 cells was attenuated. Furthermore, we found that conditioned media from hUC-MSCs transfection with siRNA targeting DKK1 mRNA or pEGFPN1-DKK1 plasmid lost or enhanced the abilities to regulate the Wnt signaling in C6 cells. Therefore, hUC-MSCs inhibited C6 glioma cell growth via secreting DKK1, an inhibitor of Wnt pathway, may represent a novel therapeutic strategy for malignant glioma. 相似文献
213.
Heloisa Einloft Palma Patrícia Wolkmer Miguel Gallio Marcos M. B. Corrêa Roberta Schmatz Gustavo R. Thomé Luciane B. Pereira Verônica S. P. Castro Andréia B. Pereira Andressa Bueno Lizielle S. de Oliveira Debora Rosolen Thaís R. Mann Bianca S. de Cecco Dominguita L. Graça Sonia T. A. Lopes Cinthia M. A. Mazzanti 《Molecular and cellular biochemistry》2014,386(1-2):199-210
This study evaluated the effects of curcumin and/or insulin on antioxidant enzyme activity in blood, liver, and kidney, as well as on lipid peroxidation and delta aminolevulinic dehydratase (δ-ALA-D) activity, and a histopathological analysis of streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 6): control/saline (C); control/curcumin (CCur); diabetic/saline (D); diabetic/insulin (DIns); diabetic/curcumin (DCur); and diabetic/insulin/curcumin (DInsCur). After 30 days of treatment with curcumin and/or insulin, the animals were sacrificed and the liver, kidney, and serum were used for experimental determinations. Results of histopathological analysis showed that the treatment with insulin ameliorate renal and hepatic lesions from both DIns and DInsCur groups. TBARS levels were significantly increased in serum, liver, and kidney in D group and the administration of curcumin and insulin prevented this increase in DIns and DCur groups. The activities of catalase (CAT), superoxide dismutase, and δ-ALA-D presented a significant decrease in the liver and kidney D group when compared to C group (P < 0.05). The animals treated with curcumin and insulin presented an increase of CAT activity, revealing a positive interaction between both substances. The treatments with curcumin or insulin prevented oxidative stress in blood, through modulation of enzymatic antioxidant defenses. These findings contributed to the comprehension that antioxidants from medicinal plants could be used as adjuvant in the treatment of this endocrinopathy and not as single therapy. 相似文献
214.
Fátima Husein Abdalla Andréia Machado Cardoso Roberta Schmatz Jamile Fabbrin Gonçalves Jucimara Baldissarelli Caroline Curry Martins Daniela Zanini Lizielle Souza de Oliveira Pauline da Costa Victor Camera Pimentel Luciane Belmonte Pereira Cibele Lima Lhamas Maria Rosa Chitolina Schetinger Vera Maria Morsch Cinthia Melazzo Andrade Mazzanti 《Molecular and cellular biochemistry》2014,396(1-2):201-211
The ex vivo and in vitro effects of quercetin on NTPDase, adenosine deaminase (ADA), and acetycholinesterase (AChE) activities in lymphocytes, as well as the effects of quercetin on butyrylcholinesterase (BChE) activity in serum and myeloperoxidase (MPO) activity in plasma were determined in rats. For the ex vivo experiment, animals were orally exposed to Cadmium (Cd) for 45 days. Animals were divided into eight groups: saline/ethanol, saline/Querc 5 mg/kg, saline/Querc 25 mg/kg, saline/Querc 50 mg/kg, Cd/ethanol, Cd/Querc 5 mg/kg, Cd/Querc 25 mg/kg, and Cd/Querc 50 mg/kg. The ex vivo data showed an increase in the ATP and ADP hydrolysis and ADA activity in Cd-exposed rats when compared to the control group. The treatment with quercetin 25 and 50 mg/kg prevented this increase in the ATP and ADP hydrolysis, while the treatment with quercetin 5, 25, and 50 mg/kg prevented the increase in the ADA activity. AChE, BChE, and MPO activities ex vivo presented an increase in the Cd-exposed group when compared to the control group, and the treatment with quercetin 5, 25, and 50 mg/kg prevented this increase caused by Cd exposure. The in vitro experiment showed that quercetin 5, 10, 25, or 50 µM decreased the ADA activity proportionally to the increase of the concentrations of quercetin when compared to the control group. Thus, we can suggest that the quercetin is able to modulate NTPDase, ADA, AChE, and MPO activities and contribute to maintain the levels of ATP, adenosine, and acetylcholine normal, respectively, exhibiting potent pro-inflammatory and anti-inflammatory actions. 相似文献
215.
Ana Paula B. Moreira Gwen Duytschaever Luciane A. Chimetto Tonon Graciela M. Dias Milene Mesquita Margo Cnockaert Ronaldo B. Francini-Filho Paul De Vos Cristiane C. Thompson Fabiano L. Thompson 《Current microbiology》2014,69(4):405-411
Three novel isolates (A-354T, A-328, and A-384) were retrieved from apparently healthy scleractinian Madracis decactis in the remote St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil. The novel isolates formed a distinct lineage based on the phylogenetic reconstruction using the 16S rRNA and pyrH gene sequences. They fell into the Mediterranei clade and their closest phylogenetic neighbour was V. mediterranei species, sharing upto 98.1 % 16S rRNA gene sequence similarity. Genomic analysis including in silico DDH, MLSA, AAI and genomic signature distinguished A-354T from V. mediterranei LMG 19703 (=AK1) with values of 33.3, 94.2, 92 %, and 11.3, respectively. Phenotypically, the novel isolates can be differentiated from V. mediterranei based on the four following features. They do not grow at 8 % NaCl; use d-gluconic acid but not l-galactonic acid lactone as carbon source; and do not have the fatty acid C18:0. Differentiation from both the other Mediterranei clade species (V. maritimus and V. variabilis) is supported by fifteen features. The novel species show lysine decarboxylase and tryptophan deaminase, but not gelatinase and arginine dihydrolase activity; produce acetoin; use α-d-lactose, N-acetyl-d-galactosamine, myo-Inositol, d-gluconic acid, and β-hydroxy-d,l-butyric acid; and present the fatty acids C14:0 iso, C15:0 anteiso, C16:0 iso, C17:0 anteiso, and C17:1x8c . Whole-cell protein profiles, based on MALDI-TOF, showed that the isolates are not clonal and also distinguished them from the closes phylogenetic neighbors. The name Vibrio madracius sp. nov. is proposed to encompass these novel isolates. The G+C content of the type strain A-354T (=LMG 28124T=CBAS 482T) is 44.5 mol%. 相似文献
216.
217.
Luciane Viater Turek Neiva Leite Ricardo Lehtonen Rodrigues Souza Jovana Karoline Lima Gerusa Eisfeld Milano Luciana da Silva Timossi Ana Claudia Vecchi Osiecki Raul Osiecki Lupe Furtado Alle 《Genetics and molecular biology》2014,37(3):490-495
In this study, we investigated the influence of two SNPs (rs846910 and rs12086634) of the HSD11B1 gene that encodes 11β-hydroxysteroid dehydrogenase type 1(11β-HSD1), the enzyme that catalyzes the conversion of cortisol to cortisone, on variables associated with obesity and metabolic syndrome in 215 individuals of both sexes from southern Brazil. The HSD11B1 gene variants were genotyped using the TaqMan SNP genotyping assay. Glucose, triglycerides, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured by standard automated methods. Significant results were found in women, with carriers of the G allele of SNP rs12086634 having higher glucose levels than non-carriers. Carriers of the A allele of SNP rs846910 had higher levels of HDL-cholesterol. The involvement of both polymorphisms as independent factors in determining the levels of glucose and HDL-cholesterol was confirmed by multiple regression analysis (β = 0.19 ±0.09, p = 0.03 and β= 0.22 ± 0.10, p = 0.03, respectively). Our findings suggest that the HSD11B1SNPs studied may indirectly influence glucose and HDL-cholesterol metabolism in women, possibly through down-regulation of the HSD11B1 gene by estrogen. 相似文献
218.
219.
Constança de Sampaio e Paiva Camilo-Alves Guilherme de Miranda Mourão 《Biotropica》2010,42(2):167-173
The goal of this study was to ascertain why the production of variable seediness is advantageous for Attalea phalerata palms. Our hypothesis was that variation reduces seed predation by the spiny rats Thrichomys pachyurus and Clyomys laticeps. Although there is a positive correlation between endocarp size and number of seeds, endocarps sometimes contain more or fewer seeds than expected; palms bluff about the number of seed per endocarp. Therefore, rats do not know how many seeds an endocarp contains. To model rats' predating behavior, we applied Charnov's Marginal Value Theorem. The model shows that rats attack endocarps only when the energy gain is higher than the energy available in the habitat. Hence, it is not advantageous to eat all the seeds inside an endocarp. This explains why 45 percent of forest endocarps and 35 percent of savanna endocarps were still viable after predation. We then applied the model to two simulated endocarp populations with less variability in the number of seeds per endocarp size and determined that viable diaspores after predation were reduced to 15 percent. With less variability, palms cannot bluff about the number of seeds inside endocarps and predators can predict accurately how many seeds they should try to eat. Uncertainty about the number of seeds diminished predation but gave selective advantage to multiseeded fruits. Therefore, the bluffing strategy would be evolutionarily stable only if it were counterbalanced by other forces. Otherwise, predators would win the bluffing game. Abstract in Portuguese is available at http://www.blackwell-synergy.com/loi/btp . 相似文献
220.