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81.
Rodolfo Iuliano Francesco Trapasso Antonella Stella Ilaria Le Pera Rosa Marina Melillo Paola Bruni Gustavo Baldassarre Lorenzo Chiariotti Massimo Santoro Giuseppe Viglietto Alfredo Fusco 《Experimental cell research》2000,260(2):257
Rat thyroid differentiated cells (PC Cl 3) are an excellent model system with which to study the interaction between differentiation and cell transformation. We previously demonstrated that PC Cl 3 cells expressing the adenovirus E1A gene no longer depend on thyrotropin for growth and do not express thyroid differentiation markers. Here we show that an E1A mutant unable to bind the RB protein failed to transform the PC Cl 3 cells. Conversely, mutations in the E1A p300 interacting region did not affect its transforming ability. The pivotal role of RB family proteins in the thyroid cell transformation is supported by the thyrotropin independence induced by the E7 gene of human papilloma virus type 16, but not by a mutated form in the RB-binding region. 相似文献
82.
83.
Teresa Teruel Angela M. Valverde Manuel Benito Margarita Lorenzo 《Journal of cellular physiology》1996,166(3):577-584
The presence of transforming growth factor β1 (TGF-β1) for 24 or 48 h stimulated DNA synthesis, the percentage of cells in the S + G2/M phases of the cell cycle, and cell number, as compared to quiescent cells. The mitogenic capacity of TGF-β1 (1 pM) was similar to that shown by 10% fetal calf serum (FCS). TGF-β1 for 48 h increased by 5-fold the percentage of cells containing (3H)thymidine-labeled nuclei as compared to quiescent cells. In addition, single fetal brown adipocytes, showing their typical multilocular fat droplets phenotype, become positive for (3H)thymidine-labeled nuclei in response to TGF-β1. Moreover, TGF-β1 induced the mRNA expression of a complete set of proliferation-related genes, such as c-fos (30 min), c-myc and β-actin (2 h), and H-ras, cdc2 kinase, and glucose 6-phosphate dehydrogenase (G6PD) at 4 and 8 h, as compared to quiescent cells. Concurrently, TGF-β1 for 12 h increased the protein content of proliferating cellular nuclear antigen (PCNA) by 6-fold and p21-ras by 2-fold. Although our results demonstrate that TGF-β1 induces the expression of very early genes related to cell proliferation, TGF-β1 could be acting either as a mitogen or as a survival factor to induce proliferation in fetal brown adipocytes. © 1996 Wiley-Liss, Inc. 相似文献
84.
Biotransformation of Natural and Synthetic Isoflavonoids by Two Recombinant Microbial Enzymes 总被引:1,自引:1,他引:1 下载免费PDF全文
Michael Seeger Myriam Gonzlez Beatriz Cmara Liliana Muoz Emilio Ponce Lorenzo Mejías Carolina Mascayano Yesseny Vsquez Silvia Sepúlveda-Boza 《Applied microbiology》2003,69(9):5045-5050
Isolation and synthesis of isoflavonoids has become a frequent endeavor, due to their interesting biological activities. The introduction of hydroxyl groups into isoflavonoids by the use of enzymes represents an attractive alternative to conventional chemical synthesis. In this study, the capabilities of biphenyl-2,3-dioxygenase (BphA) and biphenyl-2,3-dihydrodiol 2,3-dehydrogenase (BphB) of Burkholderia sp. strain LB400 to biotransform 14 isoflavonoids synthesized in the laboratory were investigated by using recombinant Escherichia coli strains containing plasmid vectors expressing the bphA1A2A3A4 or bphA1A2A3A4B genes of strain LB400. The use of BphA and BphB allowed us to biotransform 7-hydroxy-8-methylisoflavone and 7-hydroxyisoflavone into 7,2′,3′-trihydroxy-8-methylisoflavone and 7,3′,4′-trihydroxyisoflavone, respectively. The compound 2′-fluoro-7-hydroxy-8-methylisoflavone was dihydroxylated by BphA at ortho-fluorinated and meta positions of ring B, with concomitant dehalogenation leading to 7,2′,3′,-trihydroxy-8-methylisoflavone. Daidzein (7,4′-dihydroxyisoflavone) was biotransformed by BphA, generating 7,2′,4′-trihydroxyisoflavone after dehydration. Biotransformation products were analyzed by gas chromatography-mass spectrometry and nuclear magnetic resonance techniques. 相似文献
85.
Tundis R Loizzo MR Statti GA Passalacqua NG Peruzzi L Menichini F 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(7-8):467-472
Alkaloid profiles of five Senecio species (Asteraceae), including S. ambiguus subsp. ambiguus, S. ambiguus subsp. nebrodensis, S. gibbosus subsp. bicolor, S. gibbosus subsp. gibbosus, and S. gibbosus subsp. cineraria, were studied. Eleven pyrrolizidine alkaloids were identified and their content was evaluated by GLC-MS and GLC analysis. Otosenine and florosenine were found to be the major alkaloids in all studied species. It is interesting that only S. ambiguus subsp. nebrodensis was characterized by a high content of the alkaloids jacobine, jacoline, jaconine, and jacozine. 相似文献
86.
Lorenzo GD Mansueto P Melluso M Morici G Norrito F Cigna D Candore G Caruso C 《Mediators of inflammation》1995,4(4):270-272
The aim of the present study was to compare serum levels of soluble forms of interleukin-2 receptor, CD4 and CD8, released by lymphocytes during activation of the immune system, in patients with allergic bronchial asthma, with those in healthy subjects. Significantly higher levels of soluble IL-2R and soluble CD4 were found in patients with asthma compared with the control group. In contrast, lower levels of soluble CD8 values were found in patients with asthma compared to the control group. Significant correlations were found for both sIL-2R and sCD4 and these two molecules, with lung function measured as bronchial responsiveness to inhaled methacholine. These results strengthen previous suggestions that in allergic bronchial asthma, activation of T cells plays a significant role in the disease pathogenesis. 相似文献
87.
Kotaro Yamamoto Dagny Grzech Konstantinos Koudounas Emily Amor Stander Lorenzo Caputi Tetsuro Mimura Vincent Courdavault Sarah E. OConnor 《Plant physiology》2021,187(2):846
Specialized metabolites are chemically complex small molecules with a myriad of biological functions. To investigate plant-specialized metabolite biosynthesis more effectively, we developed an improved method for virus-induced gene silencing (VIGS). We designed a plasmid that incorporates fragments of both the target gene and knockdown marker gene (phytoene desaturase, PDS), which identifies tissues that have been successfully silenced in planta. To demonstrate the utility of this method, we used the terpenoid indole alkaloid (TIA) pathway in Madagascar periwinkle (Catharanthus roseus) as a model system. Catharanthus roseus is a medicinal plant well known for producing many bioactive compounds, such as vinblastine and vincristine. Our VIGS method enabled the discovery of a previously unknown biosynthetic enzyme, serpentine synthase (SS). This enzyme is a cytochrome P450 (CYP) that produces the β-carboline alkaloids serpentine and alstonine, compounds with strong blue autofluorescence and potential pharmacological activity. The discovery of this enzyme highlights the complexity of TIA biosynthesis and demonstrates the utility of this improved VIGS method for discovering unidentified metabolic enzymes in plants.An improved virus-induced gene silencing approach led to the discovery of the alkaloid biosynthetic enzyme serpentine synthase. 相似文献
88.
Hanene Cherif Hadda Ouzari Massimo Marzorati Lorenzo Brusetti Naceur Jedidi Abdennaceur Hassen Daniele Daffonchio 《World journal of microbiology & biotechnology》2008,24(7):1159-1167
Bacterial community structure and diversity of Tunisian agricultural soil treated with different amounts of municipal solid
waste compost (MSWC) and other fertilizers were studied using DGGE and ARISA fingerprinting methods. Sequence analysis of
dominant DGGE bands revealed the presence of three major clusters, Cytophaga/Flexibacter/Bacteroides (CFB) group, Proteobacteria and Acidobacteria group. Using ARISA profiles, dominant populations were assigned to low and high GC Gram positive bacteria, Cyanobacteria, Spirochetes and Cytophagales. The two methods revealed the absence of significant bacterial community shifts related to the different MSWC applications.
Moreover, indigenous bacterial population of the used loam-clayey soil was observed to limit proliferation and survival of
Proteobacteria, initially dominant in MSWC and farmyard manure. Effectiveness of the two methods for soil bacterial community studying was
shown. While DGGE was more accurate for bacterial identification, ARISA was more practical for handling and rapid estimation
of dominant bacteria. 相似文献
89.
90.
Laura?Quotti Tubi Carmela?GurrieriEmail author Alessandra?Brancalion Laura?Bonaldi Roberta?Bertorelle Sabrina?Manni Laura?Pavan Federica?Lessi Renato?Zambello Livio?Trentin Fausto?Adami Maria?Ruzzene Lorenzo?A?Pinna Gianpietro?SemenzatoEmail author Francesco?Piazza 《Journal of hematology & oncology》2013,6(1):78