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41.
Marc Haumont Jacques Magdalou Jean-Claude Ziegler Roselyne Bidault Jean-Pascal Siest Gérard Siest 《Applied microbiology and biotechnology》1991,35(4):440-446
Summary The production of glucuronides from drugs by immobilized microsomal uridine diphosphate (UDP)-glucuronosyltransferase has been investigated. Of all the immobilization methods used (covalent binding, adsorption by ionic or hydrophobic interactions), only entrapment of microsomes into alginate beads in the presence of polyethyleneimine was effective in producing high glucuronidation rates, thus leading to the formation of large amounts of metabolites. The performance of the bioreactor was optimized with the drug 3-azido-3-deoxythymidine (AZT), active against the human immunodeficiency virus, as a model substrate of UDP-glucuronosyltransferase. Calcium (12 mm) could optimally improve the stability of microsomes entrapped in alginate beads. Upon immobilization, enzyme activation occurred, leading to a fivefold increase in specific activity. The determination of apparent K
m and V
max revealed that AZT was a better substrate for the immobilized enzyme than free microsomes. The AZT-glucuronide production obtained after 6 h was threefold higher than that observed with free microsomes. This bioreactor was also efficient in production of glucuronides from structurally different compounds such as bilirubin, 4-nitrophenol, clofibric acid, pirprofen, dextrorphan or morphine, the corresponding glucuronide of which possesses pharmacological or toxicological interest.
Offprint requests to: J. Magdalou 相似文献
42.
Albert Faradji Alain Bohbot Marion Schmitt-Goguel Norbert Roeslin Serge Dumont Marie-Louise Wiesel Christian Lallot Michel Eber Jacques Bartholeyns Philippe Poindron Georges Morand Jean-Paul Witz Francis Oberling 《Cancer immunology, immunotherapy : CII》1991,33(5):319-326
Summary The purpose of this phase I study was to evaluate the toxicity and biological activity of autologous blood-derived macrophages activated ex-vivo with recombinant human interferon (rhuIFN) [monokine-activated killer (MAK) cells] and administered intravenously to 11 lung cancer patients once a week for 6 consecutive weeks. Peripheral blood monocytes were collected by leukapheresis and then purified by counterflow elutriation. The MAK cells were generated by culturing the purified monocytes in Teflon bags for 7 days and adding rhuIFN to the cultured cells for the last 18 h. These MAK cells expressed differentiation-associated surface antigen MAX1, and were cytotoxic in vitro against tumour cell line U937. The MAK cells were infused at dose levels from 1 × 107 to 5 × 108 on an intrapatient dose-escalating schedule. No severe adverse side-effects occurred. Toxicity was mild to moderate [primarly fever (75%) and chills (32%)], non-dose-dependent, and non-cumulative. No consistent change in haemostatic function, or liver or renal function was observed. Dose-limiting toxicity was not reached at 5 × 108 cells (optimal dose reproduced for each patient). The maximum tolerated dose was not determined. The immunomodulatory activity of i.v. infused MAK cells was demonstrated both in vivo by significant increases in granulocyte count and neopterin level in the patients' peripheral blood postinfusion and in vitro by secretory products (IL-1. TNF, neopterin, and thromboplastin-like substance) in the culture supernatants. The in vivo traffic patterns of autologous MAK cells labelled ex-vivo with111In oxine were studied in 7 patients. Gamma imaging showed an immediate but transient lung uptake (<24 h), and a progressive uptake of radioactivity in the liver and spleen was seen from 6 h to 72 h post-infusion. Our results indicate that the preparation of high numbers of autologous, blood-derived MAK cells is a feasible procedure, and their transfusion is safe for patients. This immunotherapeutic approach seems to be encouraging from the point of view of establishing an adjuvant therapeutic modality in cancer patients with minimal residual disease.This work was supported in part by a grant 6911 from the Association pour la Recherche contre le Cancer (ARC), grants from the Ligue Nationale contre le cancer and the Ligues Regionales (Bas-Rhin, Haut-Rhin) contre le cancer, and contract 891013 from the Institut National pour la Santé et la Recherche Médicale (INSERM), France 相似文献
43.
Duplication of HRAS1, INS, and IGF2 is not a common event in Beckwith-Wiedemann syndrome 总被引:1,自引:0,他引:1
I Henry M Jeanpierre F Barichard J L Serre J Mallet C Turleau J de Grouchy C Junien 《Annales de génétique》1988,31(4):216-220
A few cases of Beckwith-Wiedemann syndrome (BWS) have in common a duplication of 11p15. Among the genes located in 11p15, c-Ha-ras 1 (HRAS1), insulin (INS), and insulin-like growth factor II (IGF2) may account for the clinical features and the increased risk for malignancy. Using eight 11p15 markers including HRAS1, INS and IGF2 we have studied eight sporadic and hereditary cases of BWS whether or not associated with a nephroblastoma. By gene dosage determination and family studies, we have shown the following: the eight patients examined had an apparent diploid representation of all of the eight markers studied, thus indicating that a microduplication of these markers or of the region characterized by these markers is not a common event in BWS; in a family with three affected sibs the genes for HRAS1 and INS/IGF2 did not cosegregate with BWS and therefore may not participate in the pathogenic processes here observed. 相似文献
44.
Jacques Beaulaton 《The Histochemical journal》1988,20(3):131-138
Summary Calcium stores were cytochemically demonstrated using a combined oxalate—pyroantimonate method in the neuromuscular junctions of the degenerating intersegmental muscles in the giant silkmothAntheraea polyphemus. The elemental composition of punctate precipitates of the reaction product was determined by electron probe X-ray microanalysis of unstained thin sections by energy-dispersive spectrometry and wavelength-dispersive spectrometry. The wavelength-dispersive spectra collected over terminal axons demonstrate a significant calcium signal and a trace of antimony.During the rapid lytic phase of spontaneous muscle degeneration, the calcium punctate deposits were detected in presynaptic terminals in the following sites: the synaptic vesicles and the mitochondria. Calcium precipitates were also found in the dense bodies and the mitochondria encountered in the glial convolutions. No calcium deposit was seen in the synaptic clefts and intercellular spaces of the subsynaptic reticulum of type I and type II. A comparison of calcium to antimony ratios between the terminal axons and the sarcoplasmic lysosomes revealed highly significant differences (P<0.001). Such a variability of the calcium to antimony ratio may be related to different conditions of precipitation or antimony diffusion in the different cell compartments. It was concluded that such synaptic terminals do not appear damaged in spite of the muscle degeneration and presumably continue to perform vital functions while the muscles are no longer contractile 20 h after adult ecdysis. 相似文献
45.
Bioluminescence Assay for Measuring the Number of Bacteria Adhering to the Hydrocarbon Phase in the BATH Test 总被引:2,自引:2,他引:0
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A thorough validation of the bacterial adherence to hydrocarbons (BATH) test was performed by means of a bioluminescence assay. Ten different gram-negative strains were subjected to the BATH test. For the calculation of the adhesion index, several factors had to be taken into account: ATP leakage, the action of ATP-hydrolyzing enzymes, the change in the extraction efficiency of Nucleotide-Releasing Reagent for Microbial Cells (NRB; Lumac bv) after vortexing and the difference in light production after the addition of NRB. When the adhesion index values obtained by bioluminescence measurement were used as reference, the total plate count technique appeared to be unreliable in estimating the number of bacteria adhering to the hydrocarbon phase. A highly significant correlation was established, however, between those reference values and the adhesion index values obtained by the optical density reading for octane and especially for hexadecane. With xylene, no correlation was found between the optical density reading values and the total plate count or bioluminescence values. 相似文献
46.
Monique Breton Eliane Berrou M. -Christine Brahimi-Horn Elisabeth Deudon Jacques Picard 《Experimental cell research》1986,166(2)
Cultured smooth muscle cells from pig aorta arrested in G0 phase by serum deprivation were stimulated to proliferate by replacing the medium with one containing 10% serum. Studies in DNA replication and proliferation of cells showed a relatively good synchrony: 90% of the cells were in G1 phase for 16 h after addition of serum; they entered S phase between 18 and 24 h, completed S phase and traversed G2 phase between 24 and 30–32 h; 75% of these cells multiplied after 30–32 h and the remainder were blocked at the end of G2 phase. The synthesis and secretion of sulfated proteoglycans were examined throughout a full cell cycle using metabolic labelling with [35S]sulfate. Smooth muscle cells in G1 or G2 phase synthesized and secreted sulfated proteoglycans with a possible pause at the end of the G2 phase but at the beginning of the S phase and during mitosis the incorporation of [35S]sulfate into these macromolecules stopped entirely. Structural characteristics of sulfated proteoglycans secreted into the medium during G1 phase and an entire cell cycle were investigated. The proportion of proteoglycan complexes and the relative hydrodynamic size of monomers and of constituent subunits of complexes were determined after chromatography on Sepharose CL-2B and CL-6B columns run under both associative and dissociative conditions. No significant differences were observed for the periods of the cell cycle that were studied:
- 1. 1. [35S]Proteoglycan complexes represented at the end of G1 phase and of the cell cycle respectively 19 and 16% of the total [35S]proteoglycans secreted into the medium.
- 2. 2. More than 90% of the subunits, obtained after dissociation of complexes, were characterized by a similar kav after chromatography on Sepharose CL-2B columns eluted under dissociative conditions (kav 0.68 at the end of G1 phase and 0.65 at the end of full cell cycle).
- 3. 3. About 95% of monomers synthesized at the two stages of the cell cycle were eluted at kav 0.25 after chromatography on Sepharose CL-6B column run under associative conditions and were characterized by a similar glycosaminoglycan distribution. These results suggest that smooth muscle cells in culture liberate similar populations of proteoglycans into the medium during the G1 and G2 phases.
47.
Identification of Tn4430, a transposon of Bacillus thuringiensis functional in Escherichia coli 总被引:3,自引:0,他引:3
Didier Lereclus Jacques Mahillon Ghislaine Menou Marguerite-M. Lecadet 《Molecular & general genetics : MGG》1986,204(1):52-57
Summary The mobile genetic element Tn4430, originating from the gram-positive bacterium, Bacillus thuringiensis, and previously described as the Th-sequence, is the first transposon isolated from the genus Bacillus. In the present work a gene (APH-III) conferring resistance to kanamycin was inserted into this 4.2 kb transposon. Transposition experiments showed that Tn4430APH-III could transpose in the gram-negative host Escherichia coli when its insertion functions were supplied by an intact copy of Tn4430. By transposing Tn4430APH-III directly onto pBR322, it was possible to determine the nucleotide sequence of the terminal inverted repeats of Tn4430 and of the target DNA site. Identical 38 bp in inverted orientation are situated at each end of the transposon and there is a direct duplication of 5 bp at the insertion site. Thus, it is clear that Tn4430 is closely related to the transposons belonging to the Tn3 family (class II elements). 相似文献
48.
Summary Inoculation of carrot discs and Lotus corniculatus plantlets with mixtures of different Agrobacterium rhizogenes or of A. rhizogenes and A. tumefaciens or with Agrobacterium strains harboring both an Ri and a modified Ti plasmid resulted in frequent multiple (pluribacterial) transformation of cells, as revealed by the mixed opine-type of hairy roots arising from them. Multiple transformation may account for the presence of dispersed T-DNA inserts in crown gall and hairy root lines. A plant genetic engineering strategy based on segregation of T-DNA inserts in the progeny of multiple transformants is proposed. 相似文献
49.
50.
Mariann Thymann Bernadette Hoste Wolfgang Scheffrahn Jacques Constans Hartwig Cleve 《Human genetics》1985,69(3):224-227
Summary The proteins of three anodal Gc1 variants, Gc 1A16, 1A11, and 1A17, are characterized by the most acidic isoelectric points observed so far among the different Gc mutants. Stepwise removal of N-acetylneuraminic acid (NANA) by treatment with neuraminidase was performed to estimate the degree of sialilation of these Gc variants. The results indicate that both proteins, the anodal and the cathodal component of these Gc 1 mutants, carry sialic acid residues. This observation is remarkable in so far as usually only the anodal component of the Gc 1 protein contains NANA and only a single residue. From the experiments carried out it can be deduced that Gc 1A16 has two NANA residues in the anodal and one NANA residue in the cathodal component. Gc 1A16 was found in four members of three generations in a Danish family; the variant segregated as a Mendelian trait. More difficult to interprete are the results obtained with the variants Gc 1A11 and Gc 1A17. Gc 1A11 probably has three NANA residues in the anodal and two NANA residues in the cathodal component. Gc 1A11 has been observed in two mother-child pairs and is presumably also a simple genetic trait. Gc 1A17 has also several NANA residues in both Gc proteins; it is suggested that the anodal component has either three or four NANA residues and the cathodal component either two or three NANA residues. Family information on this variant is not yet available. 相似文献