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1.
Sonia Coni Silvia Maria Serrao Zuleyha Nihan Yurtsever Laura Di Magno Rosa Bordone Camilla Bertani Valerio Licursi Zaira Ianniello Paola Infante Marta Moretti Marialaura Petroni Francesca Guerrieri Alessandro Fatica Alberto Macone Enrico De Smaele Lucia Di Marcotullio Giuseppe Giannini Marella Maroder Enzo Agostinelli Gianluca Canettieri 《Cell death & disease》2020,11(12)
2.
Valerio Vidotto Giuseppe Picerno Stefano Caramello Giovanna Paniate 《Mycopathologia》1988,104(3):129-135
The passage between the yeast and mycelial forms of Candida albicans B 311-10 was studied by using the minimal syntehtic medium of Shepherd et al. [19] modified without biotin and with low glucose concentrations. It was observed that biotin, aminoacids and particularly pH are not important factors in the dimorphism of C. albicans. The only factor of notable importance in the passage of yeast form to mycelial form in C. albicans was glucose concentration. 相似文献
3.
D Valerio H van der Putten F M Botteri P M Hoogerbrugge 《Nucleic acids research》1988,16(21):10083-10097
The promoter of the human gene for adenosine deaminase (ADA) is extremely G/C-rich, contains several G/C-box motifs (GGGCGGG) and lacks any apparent TATA or CAAT boxes. These features are commonly found in promoters of genes that lack a strong tissue specificity, and are referred to as "housekeeping genes". Like other housekeeping genes, the ADA gene is expressed in all tissues. However, there is a considerable variation in the levels of expression of the ADA protein in different tissues. In order to study the activity of the ADA promoter, transgenic mice were generated that harbor a chimeric gene composed of the ADA promoter linked to a reporter gene encoding the bacterial enzyme Chloramphenicol Acetyl Transferase (CAT). These mice reproducibly showed CAT expression in all tissues examined, including the hemopoietic organs (spleen, thymus and bone marrow). However, examination of the actual cell types expressing the CAT gene revealed the ADA promoter to be inactive in the hemopoietic cells. This was substantiated by a transplantation experiment in which bone marrow from ADA-CAT transgenic mice was used to reconstitute the hemopoietic compartment of lethally irradiated mice. The engrafted recipients revealed strongly reduced CAT activity in their hemopoietic organs. The lack of expression in hemopoietic cells was further shown to be correlated with a hypermethylated state of the transgene. Combined, our data suggest that the ADA promoter sequences tested can direct expression in a wide variety of tissues as expected for a regular housekeeping gene promoter. However, the activity of the ADA promoter fragment did not reflect the tissue-specific variations in expression levels of the endogenous ADA gene. Additionally, regulatory elements are needed for expression in the hemopoietic cells. 相似文献
4.
Summary Kidney cells from primary cultures of 15-day old mouse embryos were incubated for 2, 5 or 10 min with H3-uridine, then either fixed immediately or incubated again for various periods in a chase medium containing an excess of unlabeled uridine and cytidine. The number of grains over the non-nucleolar part of the nucleus (chromatin), the nucleolus and the cytoplasm were counted on the autoradiograms.The grain count showed that both chromatin and nucleolus incorporate very rapidly H3-uridine from the medium, whereas a time lag elapses before any H3-radioactivity above background is detected in the cytoplasm. Incorporation of H3-uridine into the RNA of the nucleus and the nucleolus is not immediately blocked after chase, suggesting that the labeled precursor pool is not completely washed out from the living cell, or diluted by the excess of unlabeled uridine present in the medium. The grain count over the nucleus and the nucleolus rises for a certain time after chase and then gradually declines; H3-radioactivity appears in the cytoplasm 10 min after chase and keeps rising through a 110-min interval. The experiment, then — even though it suggests that the bulk of cellular RNA is synthesized in the chromatin and the nucleolus and then continuously released into the cytoplasm — does not rule out the possibility that some RNA fraction, characterized by a low turnover rate, is synthesized independently in the cytoplasm.Synthesis of RNA is a continuous process throughout the cell cycle, except during metaphase and anaphase. It ceases at prometaphase after the disappearance of the nucleolus and disintegration of the nuclear membrane, and resumes in early telophase. Part of the chromosomal RNA does not remain associated with the chromosomes through division, but is suddenly released into the cytoplasm when the cell enters metaphase. 相似文献
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7.
Gloria Giacomini Santo V. Nicosia Beatriz O. Saunders Caroline Fultz X. Sun Valerio M. Jasonni 《In vitro cellular & developmental biology. Animal》1995,31(4):300-309
Summary The ovarian mesothelium (OM) represents the tissue of origin of ovarian epithelial cancer. To gain insight into the regulation
of this tissue, OM organoids and submesothelial ovarian stromal cells (SC) were isolated from New Zealand White rabbits by
a stepwise tissue dispersal technique, while granulosa cells (GC) were aspirated from mature follicles (14±4 groups/animal).
OM and SC dispersal were sequentially accomplished by: a) 1-h incubation in collagenase type I (300 U/ml), gentle scraping
of the ovarian surface, and 1 g sedimentation of OM organoids (equivalent to 0.93±0.40 × 106 cells/animal) on 5% bovine serum albumin (BSA); b) 2-h incubation in pronase-collagenase (0.5%–300 U/ml) under periodical
resuspension and gentle scraping of SC (1.40±0.25 × 106/animal) from OM-denuded ovaries. After a week-long in vitro expansion, OM cells (OMC) were cultured alone and with SC or
GC within monocameral vessels or bicameral transfilter vessels in serumless, fibronectinrich (4μg/ml) HL-1 medium. After 7
d of contact cell-cell interaction, cytokeratin-positive OMC became surrounded by fibroblastoid, vimentin-positive SC or by
cytokeratin and vimentin-weakly positive GC. Filter-bound OMC humorally interacting with underlying SC or GC displayed a biphasic,
epithelioid and spindle, morphology with universal cytokeratin expression. Bromo-2′-deoxyuridine (BrdU) immunoperoxidase revealed
mean cell proliferation indices of 14.88% for OMC cultured alone, 11.21% and 19.39% for OMC cultured with GC or SC in monocameral
dishes, and 15.25% or 22.47% for OMC cultured in bicameral vessels over GC or SC, respectively. This model provides an experimental
tool for investigating the unexplored role of stromal-mesothelial interaction in OM pathobiology. 相似文献
8.
R. M. Valerio A. M. Bray N. J. Maeji P. O. Morgan J. W. Perich 《Letters in Peptide Science》1995,2(1):33-40
Summary The synthesis of two model Tyr(P)-containing peptides using Fmoc-Tyr(PO3
tBu2)-OH, Fmoc-Tyr(PO3Bzl2)-OH and Fmoc-Tyr(PO3H2)-OH established that the t-butylphosphate-protected derivative was the preferred derivative for use in Fmoc solid-phase peptide synthesis, since it afforded phosphopeptides in high purity and with the lowest amount of Tyr-peptide contamination. In addition, this study confirmed that commercially available Fmoc-Tyr(PO3H2)-OH is also suitable for use in Fmoc solid-phase synthesis but gives less pure phosphopeptides, along with the generation of 1–4% of the tyrosine-containing peptide for the model sequences studied. In view of the good performance of Fmoc-Tyr(PO3
tBu2)-OH, a large-scale three-step synthetic procedure was developed which involved phenacyl protection of the carboxyl group, phosphite-triester phosphorylation of the tyrosyl hydroxyl using di-t-butyl N,N-diethylphosphoramidite, and final removal of the phenacyl group by zinc reduction in acetic acid.Abbreviations BOP
benzotriazol-1-yl-oxy-tris(dimethylamino)phosphonium hexafluorophosphate
-
tBu
t-butyl
- Bzl
benzyl
- DBU
1,8-diazabicyclo[5,4,0]undec-7-ene
- DMF
N,N-dimethylformamide
- EDT
ethanedithiol
- Fmoc
9-fluorenylmethoxycarbonyl
- HOBt
N-hydroxybenzotriazole
- HPLC
high performance liquid chromatography
- NMM
N-methylmorpholine
- Pac
phenacyl
- TFA
trifluoroacetic acid
- THF
tetrahydrofuran
- Tyr(P)
O-phosphotyrosine 相似文献
9.
Isolation ofYersinia enterocolitica andYersinia enterocolitica-like organisms from raw milk in Italy
Thirty samples of raw milk, originating from individual producers in the Turin area, were examined for the presence ofYersinia enterocolitica. A cold enrichment method with phosphate-buffered saline (PBS) 1/15M, pH 7.6, and sorbitol-bile-salts broth (SB) was used. After 7, 14, or 21 days at 4°–5°C, plating was performed on selective agar media directly (MacConkey agar andSalmonella-Shigella agar) after the alkali method was used. Six strains ofY. enterocolitica (biotype 1) and 32 strainsY. enterocolitica-like (threeY. fredericksenii; nineYersinia rhamnose-, melibiose+, -methyl-d-glucoside+, raffinose+, probablyYersinia intermedia biotype rhamnose-; and 20Y. intermedia) were isolated.Yersinia strains were found in 11 samples of raw milk, andY. enterocolitica in four samples. 相似文献
10.
Cloning of human adenosine deaminase cDNA and expression in mouse cells 总被引:10,自引:0,他引:10
D Valerio R S McIvor S R Williams M G Duyvesteyn H van Ormondt A J van der Eb D W Martin 《Gene》1984,31(1-3):147-153