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61.
62.
In the lizard Podarcis sicula, the major vitellogenin (VTG)-derived yolk proteins, lipovitellins and phosvitins, were extracted from the yolk globules of laid and fertilized eggs at different periods of incubation up to 44 days close to hatching. Embryonic development was almost over at this time. Yolk proteins were isolated by precipitation in saturated (NH(4))(2)SO(4), separated on SDS-PAGE and detected by Western blotting with homologous polyclonal anti/VTG antibody. Two lipovitellins of 110 and 116 kDa were always present in the yolk of laid eggs after 1, 10, 18, and 44 days from oviposition. Both these proteins were glycosylated and were recognized by the anti/VTG antibody; their N-terminal sequences were analyzed. Four phosvitins were detected in freshly laid eggs, but their number decreased during incubation, and after 44 days only a single protein of approximately 6.5 kDa was present. The results indicated that, in this lizard, during embryonic development, lipovitellins remain unchanged, whereas the phosphorylated components of yolk undergo continuous degradation. 相似文献
63.
Raffaella Ponassi Barbara Biasotti Valeria Tomati Silvia Bruno Alessandro Poggi Davide Malacarne Guido Cimoli Annalisa Salis Sarah Pozzi Maurizio Miglino Gianluca Damonte Pietro Cozzini Francesca Spyrakis Barbara Campanini Luca Bagnasco Nicoletta Castagnino Lorenzo Tortolina Anna Mumot Francesco Frassoni Antonio Daga Michele Cilli Federica Piccardi Ilaria Monfardini Miriam Perugini Gabriele Zoppoli Cristina D’Arrigo Raffaele Pesenti Silvio Parodi 《Cell cycle (Georgetown, Tex.)》2012,11(19):3703
64.
Giovanna Poce Robert H. Bates Salvatore Alfonso Martina Cocozza Giulio Cesare Porretta Lluís Ballell Joaquin Rullas Fátima Ortega Alessandro De Logu Emanuela Agus Valentina La Rosa Maria Rosalia Pasca Edda De Rossi Baojie Wae Scott G. Franzblau Fabrizio Manetti Maurizio Botta Mariangela Biava 《PloS one》2013,8(2)
1,5-Diphenyl pyrroles were previously identified as a class of compounds endowed with high in vitro efficacy against M. tuberculosis. To improve the physical chemical properties and drug-like parameters of this class of compounds, a medicinal chemistry effort was undertaken. By selecting the optimal substitution patterns for the phenyl rings at N1 and C5 and by replacing the thiomorpholine moiety with a morpholine one, a new series of compounds was produced. The replacement of the sulfur with oxygen gave compounds with lower lipophilicity and improved in
vitro microsomal stability. Moreover, since the parent compound of this family has been shown to target MmpL3, mycobacterial mutants resistant to two compounds have been isolated and characterized by sequencing the mmpL3 gene; all the mutants showed point mutations in this gene. The best compound identified to date was progressed to dose-response studies in an acute murine TB infection model. The resulting ED99 of 49 mg/Kg is within the range of commonly employed tuberculosis drugs, demonstrating the potential of this chemical series. The in vitro and in vivo target validation evidence presented here adds further weight to MmpL3 as a druggable target of interest for anti-tubercular drug discovery. 相似文献
65.
Stranges S Rafalson LB Dmochowski J Rejman K Tracy RP Trevisan M Donahue RP 《Obesity (Silver Spring, Md.)》2008,16(6):1370-1376
Objective: To examine whether several biomarkers of endothelial function and inflammation improve prediction of type 2 diabetes over 5.9 years of follow‐up, independent of traditional risk factors. Methods and Procedures: A total of 1,455 participants from the Western New York Study, free of type 2 diabetes at baseline, were selected. Incident type 2 diabetes was defined as fasting glucose exceeding 125 mg/dl or on antidiabetic medication at the follow‐up visit. Sixty‐one people who met the case definition (8/1,000 person years) were identified and individually matched with up to three controls on gender, race, year of study enrollment, and baseline fasting glucose (<110 or 110–125 mg/dl). Biomarkers were measured from frozen baseline samples. Results: In conditional logistic regression analyses accounting for traditional risk factors (age, family history of diabetes, smoking, drinking status, and BMI), E‐selectin was positively related (3rd vs. 1st tertile: odds ratio 2.77, 95% confidence interval (CI) 1.13–6.79, P for linear trend = 0.023) and serum albumin was inversely related (3rd vs. 1st tertile: odds ratio 0.36, 95% CI 0.14–0.93, P for linear trend = 0.032) to type 2 diabetes incidence. The addition of E‐selectin, serum albumin, and leukocyte count to a basic risk factor model including only traditional risk factors significantly increased the area under the receiver operating characteristic curve (AUC) (from 0.646 to 0.726, P value = 0.04). Discussion: These results support the role of endothelial dysfunction and subclinical inflammation as important mechanisms in the etiopathogenesis of type 2 diabetes; moreover, they indicate that novel biomarkers may improve the prediction of type 2 diabetes beyond the use of traditional risk factors alone. 相似文献
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Functional heterogeneity of vaccine-induced CD8(+) T cells 总被引:5,自引:0,他引:5
Monsurrò V Nagorsen D Wang E Provenzano M Dudley ME Rosenberg SA Marincola FM 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(11):5933-5942
The functional status of circulating vaccine-induced, tumor-specific T cells has been questioned to explain their paradoxical inability to inhibit tumor growth. We enumerated with HLA-A*0201/peptide tetramers (tHLA) vaccine-elicited CD8(+) T cell precursor frequency among PBMC in 13 patients with melanoma undergoing vaccination with the HLA-A*0201-associated gp100:209-217(210 M) epitope. T cell precursor frequency increased from undetectable to 12,400 +/- 3,600 x 10(6) CD8(+) T cells after vaccination and appeared heterogeneous according to previously described functional subtypes: CD45RA(+)CD27(+) (14 +/- 2.6% of tHLA-staining T cells), naive; CD45RA(-)CD27(+) (14 +/- 3.2%), memory; CD45RA(+)CD27(-) (43 +/- 6%), effector; and CD45RA(-)CD27(-) (30 +/- 4.1%), memory/effector. The majority of tHLA(+)CD8(+) T cells displayed an effector, CD27(-) phenotype (73%). However, few expressed perforin (17%). Epitope-specific in vitro stimulation (IVS) followed by 10-day expansion in IL-2 reversed this phenotype by increasing the number of perforin(+) (84 +/- 3.6%; by paired t test, p < 0.001) and CD27(+) (from 28 to 67%; by paired t test, p = 0.01) tHLA(+) T cells. This conversion probably represented a change in the functional status of tHLA(+) T cells rather than a preferential expansion of a CD27(+) (naive and/or memory) PBMC, because it was reproduced after IVS of a T cell clone bearing a classic effector phenotype (CD45RA(+)CD27(-)). These findings suggest that circulating vaccine-elicited T cells are not as functionally active as inferred by characterization of IVS-induced CTL. In addition, CD45RA/CD27 expression may be more informative about the status of activation of circulating T cells than their status of differentiation. 相似文献
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70.
Fiorenza Lagona M. Smid Nadia Papasergio Augusto Ferrari Maurizio Ferrari Laura Cremonesi 《Human genetics》1998,102(6):687-690
Fetal male DNA can be identified in maternal blood by polymerase chain reaction (PCR) amplification of Y-specific sequences.
This technology has not reached a satisfactory accuracy and reproducibility in fetal gender determination because of the very
low concentration of fetal cells. Our purpose was to evaluate the possibility of improving the reliability of this test by
setting up a repeated amplification system. We amplified, by nested PCR of the Y-specific sequence DYS14, 137 DNA samples
extracted from maternal peripheral blood (93 from male-bearing and 44 from female-bearing pregnancies ranging from the 6th
to the 36th gestational week). Each maternal DNA sample was tested doubly, in two different PCR sessions, with a total of
four amplifications. We obtained discordant results in the four amplifications in 82/137 (60%) samples. The best interpretation
of these discordant results was obtained by applying a positivity cutoff of at least two positive amplifications for considering
a DNA sample as belonging to a male-bearing pregnancy. We obtained a sensitivity of 83%, a specificity of 93%, a positive
predictive value of 96% and a negative predictive value of 72% in fetal male gender diagnosis. By applying this quadruple
testing system, we significantly improved PCR accuracy and predictive values compared with single and double testing of the
same samples. We conclude that, for future investigations of fetal DNA retrieved from maternal blood, the application of a
quadruple testing system is better than the single PCR test.
Received: 18 August 1997 / Accepted: 12 January 1998 相似文献