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551.
552.
Ariane Plet Yoheved Berwald-Netter 《Biochemical and biophysical research communications》1980,94(3):744-754
Culture conditions were defined allowing to demonstrate a stimulatory effect of both serum-contained and purified Somatomedin activity on incorporation of [3H]thymidine and replication of cultured normal human fibroblasts. The use of dialyzed human serum in MEM medium supplemented by 0.2 mM serine offered the necessary and sufficient culture conditions. A significant difference between normal and hypopituitary patients sera was found in their effect on the rate of [3H]thymidine incorporation (p < 0.0001) and on cell replication (p < 0.01). Purified Somatomedin-C, in MEM without serum, is a poor mitogen. Its activity was strongly enhanced by the addition of 0.1 % dialyzed serum and 0.2 mM serine without, however, exceeding the stimulatory level of 1 % whole normal serum. The requirement of concomitant presence, for optimal cell growth, of different low and high MW serum components is discussed. 相似文献
553.
G. Sauret-Ignazi Jean Gagnon Claude Béguin Michel Barrelle Yves Markowicz Jean Pelmont Ariane Toussaint 《Archives of microbiology》1996,166(1):42-50
Alcaligenes eutrophus CH34 used benzoate as a sole source of carbon and energy, degrading it through the 3-oxoadipate pathway. All the enzymes
required for this degradation were shown to be encoded by chromosomal genes. Catechol 1,2-dioxygenase activity was induced
by benzoate, catechol, 4-chlorocatechol, and muconate. The enzyme is most likely a homodimer, with an apparent molecular weight
of 76,000 ± 500. According to several criteria, its properties are intermediate between those of catechol 1,2-dioxygenases
(CatA) and chlorocatechol 1,2-dioxygenases (ClcA). The determined K
m for catechol is the lowest among known catechol and chlorocatechol dioxygenases. Similar K
m values were found for para-substituted catechols, although the catalytic constants were much lower. The catechol 1,2-dioxygenase from strain CH34 is
unique in its property to transform tetrachlorocatechol; however, excess substrate led to a marked reversible inhibition.
Some meta- and multi-substituted catechols behaved similarly. The determined K
m (or K
i) values for para- or meta-substituted catechols suggest that the presence of an electron-withdrawing substituent at one of these positions results
in a higher affinity of the enzyme for the ligand. Results of studies of recognition by the enzyme of various nonmetabolised
aromatic compounds are also discussed.
Received: 20 November 1996 / Accepted: 11 April 1996 相似文献
554.
Francesca Rocchi Hiroyuki Oya Fabien Balezeau Alexander J. Billig Zsuzsanna Kocsis Rick L. Jenison Kirill V. Nourski Christopher K. Kovach Mitchell Steinschneider Yukiko Kikuchi Ariane E. Rhone Brian J. Dlouhy Hiroto Kawasaki Ralph Adolphs Jeremy D.W. Greenlee Timothy D. Griffiths Matthew A. Howard Christopher I. Petkov 《Neuron》2021,109(5):852-868.e8
Download : Download video (20MB) 相似文献
555.
556.
557.
Ariane Plet Pascale Gerbaud Wayne B. Anderson Danièle Evain Brion 《Differentiation; research in biological diversity》1985,30(2):159-164
We investigated changes in the activity and subcellular distribution of cyclic-AMP-dependent protein kinases (cAMP-PKs) in response to treatment with retinoic acid in three different embryonal carcinoma cell lines derived from the same teratoma 6050. After retinoic-acid treatment, F9 and PCC4 cells gave rise to parietal-like endoderm, while PC13 cells differentiated into visceral endoderm. Retinoid treatment of F9 and PCC4 cells caused an increase in cAMP-PK activity as measured by histone phosphorylation, as well as increases in the amount of the RI and RII regulatory subunits of the cAMP-PKs, as quantitated by photoaffinity labeling with 8-azido-cyclic-32P-AMP, in both the soluble and plasma-membrane fractions. The increases in membrane cAMP-PK activity and RI and RII levels reached their maximum within 18 h of retinoid treatment, and then dropped to intermediate levels after 3 days of treatment. The cytosolic activity and the levels of the regulatory subunits exhibited a progressive increase during the 3 days of exposure to retinoic acid. The relative RI/RII ratios in the cytosol and membrane fractions of the treated cells were comparable to those found in established PYS-2 parietal-endoderm cells. PC13 stem cells had high levels of cAMP-PK activity and cAMP binding to the regulatory subunits in both the cytosol and plasma membranes, while also exhibiting very low levels of type-II cAMP-PK. Retinoid treatment induced a progressive increase in cAMP-PK activity in the cytosol, and a decrease in activity at the membrane level.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
558.
Summary Chromosome analysis of the amnion from a spontaneous abortus revealed a 47,XX,D+karyotype. Giemsa banding pattern technique identified the extra chromosome as a No. 14.
This study was supported by the Ford Foundation Population Program, Grant No. 640-0411B and by the World Health Organisation. 相似文献
Zusammenfassung Die Chromosomenanalyse der Amnionzellen eines Spontanaborts zeigte einen Karyotyp 47,XX,D+. Mit der Giemsamusterfärbung wurde das Extrachromosom als Nr. 14 identifiziert.
This study was supported by the Ford Foundation Population Program, Grant No. 640-0411B and by the World Health Organisation. 相似文献
559.
560.
Céline Mayet Ariane Deniset-BesseauRui Prazeres Jean-Michel OrtegaAlexandre Dazzi 《Biotechnology advances》2013
In this paper, we will employ two microscopy techniques, transmission electron microscopy and infrared nanospectromicroscopy, to study the production of polyhydroxybutyrate in Rhodobacter capsulatus and to evaluate the influence of glucose and acetone on the production yield. The results overlap which leads us to a consistent conclusion, highlighting that each technique brings specific and complementary information. By using electron microscopy and infrared nanospectromicroscopy we have proved that both glucose and acetone had a positive effect on the biopolymer production, although the first study done by Fourier transform infrared spectroscopy only identified the effect of acetone. In conclusion, we have now established a method to be able to perform fast diagnostic for PHB production. 相似文献