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1.
Patterns of Sleeping Site and Sleeping Tree Selection by Black-and-Gold Howler Monkeys (Alouatta caraya) in Northern Argentina 总被引:1,自引:0,他引:1
Brividoro Melina V. Kowalewski Martin M. Scarry Clara J. Oklander Luciana I. 《International journal of primatology》2019,40(3):374-392
International Journal of Primatology - The selection of sleeping sites and sleeping trees in nonhuman primates is related to social and ecological factors. We investigate the role of body... 相似文献
2.
Synthetic peptides including acidic clusters as substrates and inhibitors of rat liver casein kinase TS (type-2) 总被引:10,自引:0,他引:10
F Meggio F Marchiori G Borin G Chessa L A Pinna 《The Journal of biological chemistry》1984,259(23):14576-14579
The hexapeptides AcSer-Glu-Glu-Glu-Val-Glu and Ser-Glu-Glu-Glu-Glu-Glu, reminiscent of the sites phosphorylated by type-2 casein kinase TS in troponin T and glycogen synthase, respectively, have been synthesized and tested as phosphorylatable substrates for casein kinase TS as well as for other protein kinases. Both peptides are readily phosphorylated by casein kinase TS but not, to any detectable extent, by either cAMP-dependent protein kinase or phosphorylase kinase. Phosphorylation by type-1 casein kinase S was almost negligible. On the other hand the hexapeptide Ser-Glu-Glu-Glu-Ala-Ala is phosphorylated much more slowly and the hexapeptide Ser-Glu-Glu-Ala-Ala-Ala is almost unaffected by casein kinase TS. While the Vmax values of casein kinase TS with the acidic hexapeptides are comparable to those obtained with the corresponding protein substrates, the apparent Km values for the peptides are about two orders of magnitude higher than those for the protein substrates. The heptapeptide Arg-Ser-Glu-Glu-Glu-Val-Glu is a very poor substrate of casein kinase TS in comparison with the corresponding hexapeptide lacking the N-terminal Arg; it is, however, a competitive inhibitor toward the protein substrates, exhibiting a Ki similar to those of Ser-Glu-Glu-Glu-Glu-Glu and (Glu)5 which, in turn, are one order of magnitude higher than that of (Glu)10. It is concluded that the minimum structural requirement of type-2 casein kinases consists of a phosphorylatable residue followed by an acidic cluster, whose length is critical for the binding to the enzyme. Additional residues on the N-terminal side are not required, but their nature can influence the transphosphorylation reaction considerably. 相似文献
3.
Michelle de C. S. Azevedo Patricia S. Rosa Cleverson T. Soares Luciana R. V. Fachin Ida Maria F. D. Baptista William J. Woods Gustavo P. Garlet Ana Paula F. Trombone Andrea de F. F. Belone 《PloS one》2015,10(12)
Jorge Lobo’s disease (JLD) is a chronic infection that affects the skin and subcutaneous tissues. Its etiologic agent is the fungus Lacazia loboi. Lesions are classified as localized, multifocal, or disseminated, depending on their location. Early diagnosis and the surgical removal of lesions are the best therapeutic options currently available for JLD. The few studies that evaluate the immunological response of JLD patients show a predominance of Th2 response, as well as a high frequency of TGF-β and IL-10 positive cells in the lesions; however, the overall immunological status of the lesions in terms of their T cell phenotype has yet to be determined. Therefore, the objective of this study was to evaluate the pattern of Th1, Th2, Th17 and regulatory T cell (Treg) markers mRNA in JLD patients by means of real-time PCR. Biopsies of JLD lesions (N = 102) were classified according to their clinical and histopathological features and then analyzed using real-time PCR in order to determine the expression levels of TGF-β1, FoxP3, CTLA4, IKZF2, IL-10, T-bet, IFN-γ, GATA3, IL-4, IL-5, IL-13, IL-33, RORC, IL-17A, IL-17F, and IL-22 and to compare these levels to those of healthy control skin (N = 12). The results showed an increased expression of FoxP3, CTLA4, TGF-β1, IL-10, T-bet, IL-17F, and IL-17A in lesions, while GATA3 and IL-4 levels were found to be lower in diseased skin than in the control group. When the clinical forms were compared, TGF-β1 was found to be highly expressed in patients with a single localized lesion while IL-5 and IL-17A levels were higher in patients with multiple/disseminated lesions. These results demonstrate the occurrence of mixed T helper responses and suggest the dominance of regulatory T cell activity, which could inhibit Th-dependent protective responses to intracellular fungi such as L. loboi. Therefore, Tregs may play a key role in JLD pathogenesis. 相似文献
4.
Luciana Mastrantuono 《Aquatic Ecology》1988,22(2):195-198
The analysis of gut contents ofAmphichaeta leydigii, found for the first time in Italy in sandy shores of Lake Vico (Central Italy), proved grazing of the species on diatoms (Centrales and Pennales). Detritus and organic particles, abundant in the substratum, were observed only in small amounts. 相似文献
5.
Bruna Tadolini Diana Fiorentini Laura Landi Luciana Cabrini 《Free radical research》1989,5(4):245-252
To find experimental conditions to selectively study the propagation phase of lipoperoxidation we studied the lipoperoxidation, catalyzed by FeCl2, of liposomes in a buffering condition where Fe2+ autoxidation and oxygen active species generation does not occur. Liposomes from egg yolk phosphatidylcholine. prepared by vortex mixing, do not oxidize Fe2+: on the contrary they oxidize Fe2+ when prepared by ultrasonic irradiation. Dimyristoyl phosphatidylcholine liposomes prepared by ultrasonic irradiation do not oxidize Fe2+. During sonication polyunsaturated fatty acid residues autoxidize and lipid hydroperoxides (LOOH) are generated. Only when LOOH are present in the liposimes Fe2+ oxidizes and its rate of oxidation depends on the amount of LOOH in the assay. The reaction results in the generation of both LOOH and thiobarbituric acid reactive material (TBAR): it is inhibited by butylated hydroxytoluene and has a acidic pH optimum; it is not inhibited by catalase and OH' scavengers. The reaction studied. thus, appears to be the chain branching and propagation phase of lipoperoxidation. When we studied the dependence of Fe2+ oxidation, LOOH and TBAR generation on FeCl2 concentration, we observed that at high FeCl2 concentrations the termination phase of lipoperoxidation was prevalent. Thus. by selecting the appropriate FeCl2 concentration the proposed experimental system allows study of either the propagation or the termination phase of lipoperoxidation. 相似文献
6.
Luciana A. Haddad Regina C. Mingroni-Netto Angela M. Vianna-Morgante Sérgio D. J. Pena 《Human genetics》1996,97(6):808-812
Ever since the identification of the genetic cause of fragile X syndrome as the expansion of an unstable trinucleotide sequence,
several diagnostic strategies have evolved from molecular studies. However, we still lack a simple test suitable for population
screening. We have therefore developed a nonisotopic polymerase chain reaction (PCR)-based technique for the identification
of fragile X full mutations among men, with easy visualization of the PCR products on silver-stained polyacrylamide gels.
The technique consists of PCR amplification with primers that flank the trinucleotide repeats, with a product of 557 bp for
the (CGG)29 allele. Conditions were established such that full mutations failed to amplify and were thus identified with 98% sensitivity
compared with Southern blot analysis. To produce an indispensable internal control we added to the reaction a third primer,
internal to this fragment, allowing the multiplex amplification of a monomorphic band corresponding to a CG-rich stretch 147
bp upstream of the polymorphic region. In trials involving 41 patients and 74 controls, the PCR-based test here described
showed specificity of more than 98.6%, accuracy of 99% and a sensitivity of 98%. Thus, although not suitable for medical diagnosis,
it constitutes a useful tool for screening for the fragile X syndrome in populations of mentally retarded males.
Received: 31 May 1995 / Revised: 4 October 1995 相似文献
7.
8.
Enrico Crivellato Luciana Travan Luigi Candussio Fiora Bartoli Klugmann Giuliana Decorti 《The Histochemical journal》1997,29(3):193-198
The presence of P-glycoprotein has been investigated in rat peritoneal mast cells by means of immunofluorescence and immunogold
electron microscopy, using the specific monoclonal antibody JSB-1. Immunofluorescence studi es showed that the glycoprotein
is primarily concentrated in mast cell granules, and little is localized at the plasma membrane. Electron microscope observations
revealed a marked accumulation of colloidal gold particles at the granule-coating membranes, whereas decoration of the plasma
membrane is much less intense. When mast cells are stimulated to exocytate with compound 48/80, both immunofluorescence and
electron microscopy showed concentration of P-glycoprotein reactivity at the plasma membrane level. Indeed, fusion of the
granule with the plasma membrane allowed transfer of immunoreactive P-glycoprotein material from the granule-coating membrane
to the cell surface membrane. These findings confirmed the presence of P-glycoprotein in mast cells; it is predominantly localized
in the granules and is exposed on the cell surface only after exocytosis, suggesting, therefore, a possible physiological
role for P-glycoprotein in the secretion of certain mediators.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
9.
10.
Summary A male patient with mental retardation and typical clinical features of 10p trisomy syndrome was found to have a duplication of the short arm of chromosome 10 attached to the short arm of the Y chromosome.Quantitative evaluation of nine red cell enzymes showed significantly increased activity levels of HK1 and, to a lesser extent, of PK, PGI, 6PGD, and G6PD. It is suggested that the HK1 locus may be in the 10pterp12 region. The increased levels of HK1 could affect other erythrocyte metabolic pathways slowing down the physiological rate of cellular senescence and result in increased activity levels of other cell-age-dependent enzymes. 相似文献