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91.
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R Selvatici M Rubini P Orlando A Balboni S Balugani E Gandini 《Biochemistry international》1991,25(1):151-158
HLA class I antigens seem to be involved in the proliferative response of PHA-activated human T-lymphocytes. We have previously reported that the treatment of PHA-activated peripheral blood mononuclear cells (PBMC) with an anti-HLA class I monoclonal antibody, 01.65, (i) inhibits the tritiated thymidine incorporation, (ii) inactivates cytosolic protein kinase C (PKC) and (iii) causes an increase in the duration of the cell cycle. Northern Blot kinetic analysis of c-fos, c-myc, cdc2, IL-2R, c-myb, ODC, TK and H3, from 10 minutes to 120 hours, was performed in MAb 01.65 treated cultures. We found that the expression of four genes (c-myc, IL-2R, cdc2 and TK) was depressed 24 hours after PHA stimulation. 相似文献
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95.
Marcelo De Franco Patrícia dos Santos Carneiro Luciana Carla Peters Francisca Vorraro Andrea Borrego Orlando Garcia Ribeiro Nancy Starobinas Wafa Koury Cabrera Olga Martinez Ibañez 《Mammalian genome》2007,18(4):263-269
Lines of mice were obtained by selective breeding for maximum (AIRmax) or minimum (AIRmin) acute inflammation. They present
distinct neutrophil influx and show frequency disequilibrium of the solute carrier family 11a member 1
(Slc11a1) alleles. This gene is involved in ion transport at the endosomes within macrophages and neutrophils, interfering in their
activation. Homozygous AIRmax and AIRmin sublines for the Slc11a1 gene were produced to examine the interaction of this gene with the acute inflammatory loci. The present work investigated
wound-healing traits in AIRmax and AIRmin mice, in F1 and F2 intercrosses, and in Slc11a1 sublines. Two-millimeter ear punches were made in the mice and hole closure was measured during 40 days. AIRmax mice demonstrated
significant tissue repair while AIRmin mice did not. Significant differences between the responses of male and female mice
were also observed. Wound-healing traits demonstrated a correlation with neutrophil influx in F2 populations. AIRmax
SS
showed higher ear-wound closure than AIRmax
RR
mice, suggesting that the Slc11a1
S allele favored ear tissue repair. QTL analysis has detected two inflammatory loci modulating ear wound healing on chromosomes
1 and 14. These results suggest the involvement of the acute inflammation modifier QTL in the wound-healing phenotype. 相似文献
96.
Levasseur A Orlando L Bailly X Milinkovitch MC Danchin EG Pontarotti P 《Biological reviews of the Cambridge Philosophical Society》2007,82(4):551-572
To demonstrate that a given change in the environment has contributed to the emergence of a given genotypic and phenotypic shift during the course of evolution, one should ask to what extent such shifts would have occurred without environmental change. Of course, such tests are rarely practical but phenotypic novelties can still be correlated to genomic shifts in response to environmental changes if enough information is available. We surveyed and re-evaluated the published data in order to estimate the role of environmental changes on the course of species and genomic evolution. Only a few published examples clearly demonstrate a causal link between a given environmental change and the fixation of a genomic variant resulting in functional modification (gain, loss or alteration of function). Many others suggested a link between a given phenotypic shift and a given environmental change but failed to identify the underlying genomic determinant(s) and/or the associated functional consequence(s). The proportion of genotypic and phenotypic variation that is fixed concomitantly with environmental changes is often considered adaptive and hence, the result of positive selection, even though alternative causes, such as genetic drift, are rarely investigated. Therefore, the second aim herein is to review evidence for the mechanisms leading to fixation. 相似文献
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98.
Fernanda S. Freitas Orlando C. De‐Paula Jimi N. Nakajima Juliana Marzinek 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(2):255-265
Heterocoma is a Brazilian endemic genus resulting from the dismemberment of Sipolisiinae, in which only representatives with fruit containing phytomelanin were included in the genus. As the fruits of Asteraceae are known to be systematically important at various taxonomic levels and Heterocoma fruit has not been described previously, we studied the morphology and anatomy of the cypselas of all species of the genus, comparing them with other fruits in the family containing phytomelanin and evaluating the systematic potential at the specific and tribal levels. The fruits were analysed by scanning electron microscopy (SEM) and light microscopy. The morphological features of the fruit, including the carpopodium, ribs and pappi, varied in the genus and demonstrated potential for species discrimination. The anatomy showed a pattern for the genus with a uniseriate exocarp, the outer mesocarp composed of fibres arranged in several layers, the inner mesocarp composed of several layers of parenchyma, the endocarp, and phytomelanin deposited between the inner and outer mesocarp. This anatomical pattern of phytomelanin deposition differs from that of other Asteraceae with phytomelanin in their fruit. Heterocoma is also the only genus in Vernonieae that has phytomelanin deposition in the cypselas. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 255–265. 相似文献
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100.
Spadoni G Bedini A Orlando P Lucarini S Tarzia G Mor M Rivara S Lucini V Pannacci M Scaglione F 《Bioorganic & medicinal chemistry》2011,19(16):4910-4916
We report the synthesis, binding properties and intrinsic activity at MT(1) and MT(2) melatonin receptors of new dimeric melatonin receptor ligands in which two units of the monomeric agonist N-{2-[(3-methoxyphenyl)methylamino]ethyl}acetamide (1) are linked together through different anchor points. Dimerization of compound 1 through the methoxy substituent leads to a substantial improvement in selectivity for the MT(1) receptor, and to a partial agonist behavior. Compound 3a, with a trimethylene linker, was the most selective for the MT(1) subtype (112-fold selectivity) and compound 3d, characterized by a hexamethylene spacer, had the highest MT(1) binding affinity (pK(iMT1)=8.47) and 54-fold MT(1)-selectivity. Dimerization through the aniline nitrogen of 1 abolished MT(1) selectivity, leading to compounds with either a full agonist or an antagonist behavior depending on the nature of the linker. 相似文献