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21.
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 q358/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> (rhuIFNq358/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0">) [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 rhuIFNq358/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"> 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. TNFq358/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">, 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
22.
Summary With the aim of comparing the primary structures of gene products coded for by T-even bacteriophages we constructed clone libraries of the DNAs of bacteriophages T2 and T6. Using hybrid M13 phages carrying the gene for the T4-coded q45/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-glucosyl transferase (q45/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">gt) we isolated corresponding T2 and T6 clones. The nucleotide sequences of the three q45/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">gt genes and the amino acid sequences derived were compared. The differences between the genes and their products are discussed in terms of structure, function and evolutionary aspects.Abbreviations bp
base pair
- gt
glucosyl transferase
- HMC
5-hydroxymethyl cytosine
- orf
open reading frame
- Xgal
5-bromo-4-chloro-3-indolyl-q45/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-d-galactoside 相似文献
23.
Substrate and inhibitor specificity of anion exchangers on the brush border membrane of rabbit ileum
Roy G. Knickelbein Peter S. Aronson John W. Dobbins 《The Journal of membrane biology》1985,88(2):199-204
Summary In previous studies we have found that several anions can be transported by an exchange process in rabbit ileal brush border membranes. We demonstrated exchanges of Cl for OH or HCO3, SO4 for OH, oxalate for OH, and oxalate for Cl. The purpose of these studies was to determine the number of distinct carriers mediating these exchanges. We utilized substrate and inhibitor specificity studies to distinguish between different anion exchange transporters. We conclude that SO4q0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">OH and oxalate: OH exchange occur on the same carrier because: (i) pH-gradient stimulated transport of both14C-oxalate and35SO4 were equally sensitive tocis-inhibition by unlabeled SO4 or oxalate; and (ii) both were inhibited equally by K. We conclude that oxalate: OH and oxalate: Cl exchanges occur on different carriers because: (i) Cl or SO4 caused unequalcis-inhibition of these two exchanges; and (ii) as compared to oxalate: Cl exchange, oxalate: OH exchange was more sensitive to inhibition by probenecid and K and less sensitive to inhibition by bumetanide. Finally, we conclude that oxalate: Cl exchange and Clq0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">HCO3 exchange occur on different carriers because: (i) Clq0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">HCO3 exchange was almost completely insensitive tocis-inhibition by oxalate; and (ii) oxalate: Cl exchange was more sensitive to inhibition by DIDS and bumetanide than Clq0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">HCO3 exchange. Thus we have found that there are at least three separate anion exchangers on rabbit ileal brush border: (i) a Clq0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">HCO3 exchanger; (ii) a SO4q0q6371156827424/xxlarge8758.gif" alt="ratio" align="BASELINE" BORDER="0">OH exchanger, which also transports oxalate; and (iii) an oxalate: Cl exchanger. 相似文献
24.
J. Wiegel 《Archives of microbiology》1985,142(2):194-199
The q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-isopropylmalate synthase of the chemolithoautotrophic Alcaligenes eutrophus H16 is apparently a soluble enzyme but is strongly adsorbed to cell particles in ruptured cell suspensions. This was not observed with q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-acetohydroxy acid synthase or threonine deaminase. The formation of these regulatory enzymes of the branched chain amino acid biosynthesis pathway generally decreased with decreased growth rates. The addition of 5 mM valine plus isoleucine with and without 5 mM threonine caused a 6.6- and a 4-fold increase, respectively, in the formation of active q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-isopropylmalate synthase, but caused a strong decrease in the q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-actohydroxy acid synthase. The level of active q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-isopropylmalate synthase is apparently regulated by the level of leucine; whereas, the level of the q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-acetohydroxy acid synthase and threonine deaminase is influenced by the presence of several amino acids. A catabolic threonine deaminase was not encountered.Abbreviations IRS
q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-Isopropylamalate
- AHA
q12706322u146/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-acetohydroxy acid
- TDA
throninedeaminase
This paper is dedicated to Professor H. G. Schlegel, University Göttingen, on the occasion of his 60th birthday. I am grateful to a great teacher and scientist, who in his unique way stimulated enthusiasm and fascination in microbiology in his students throughout the years 相似文献
25.
Summary A brief review is presented of the Vester-Ulbricht q23/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-decay Bremsstrahlen hypothesis for the origin of optical activity, and of subsequent experiments designed to test it. Certain of our experiments along these lines, begun in 1974 and involving the irradiation of racemic and optically active amino acids in a 61.7 KCi90Sr–90Y Bremsstrahlen source, have now been completed and are described. After 10.89 years of irradiation with a total Bremsstrahlen dose of 2.5×109 rads, crystallinedl-leucine, norleucine, and norvaline suffered 47.2, 33.6, and 27.4% radiolysis, respectively, but showed no evidence whatsoever of asymmetric degradation.d- andl-Leucine underwent about 48% radiolysis and showed 2.4–2.9% radioracemization. Other samples in solution were too severely degraded to analyze. Probable intrinsic reasons for the failure of the Vester-Ulbricht mechanism to afford asymmetric radiolysis in the present and related experiments involving q23/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-decay Bremsstrahlen are enumerated.A portion of this material was presented at the 7th International Conference on the Origins of Life, Mainz, FRG, July 10–15, 1983 相似文献
26.
Polymer chains of (1q41w4219/xxlarge8594.gif" alt="rarr" align="BASELINE" BORDER="0">3)-q41w4219/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-d-glucan were dissolved with 1 M NaOH at 4° C from native microfibrillar protoplast nets. The chains associated into microfibrils during NaOH neutralization or dialysis. In contrast to the native microfibrils which are of uniform width individually (10 to 20 nm) and arranged in flat bundles, the microfibrils formed in vitro showed no band formation and consisted of fibrous spindle-shaped subunits of variable width or loose elementary fibrils about 1.7 nm wide. X-ray diagrams of native nets indicated a fairly high crystallinity and were different for wet and dry specimens. They corresponded to those of paramylon. Precipitated glucans produced diagrams different from the former and revealing a lower crystallinity especially with the dry samples.The X-ray pattern, combined with other data, allowed the precipitated microfibrils to be identified as aggregates of molecular strands composed each of three intertwined helical glucan chains. Since these triple helical chains are about 1.7 nm wide the elementary fibrils of this width can represent only single triple-helical strands. These helices have 7 glucose residues per turn and therefore a low symmetry which explains the poor crystallizing properties. The 7 membered helix represents a basic difference with the well crystallized native glucan which is built of highly symmetrical triple helices with 6 glucose residues per turn. Since 61 helical conformation is not formed in vitro at normal temperatures its generation in vivo must be due to the action of synthesizing enzymes at the protoplast membrane. The intertwining of these helices and crystallization of the strands are determined by their symmetry and physical properties of the chains. This characterizes the native microfibrils as products of self-assembly of enzymegenerated 61 helices. 相似文献
27.
K. Manning 《Planta》1986,168(1):61-66
The relationship between ethylene production and the CN--assimilating enzyme q6x70716677865n3/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyanoalanine synthase (CAS; EC 4.4.1.9) was examined in the carnation (Dianthus caryophyllus L.) flower. In petals from cut flowers aged naturally or treated with ethylene to accelerate senescence the several hundred-fold increase in ethylene production which occurred during irreversible wilting was accompanied by a one- to twofold increase in CAS activity. The basal parts of the petal, which produced the most ethylene, had the highest CAS activity. Studies of flower parts (styles, ovaries, receptacles, petals) showed that the styles had a high level of CAS together with the ethylene-forming enzyme (EFE) system for converting 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene. The close association between CAS and EFE found in styles could also be observed in detached petals after induction by ACC or ethylene. Treatment of the cut flowers with cycloheximide reduced synthesis of CAS and EFE. The data indicate that CAS and ethylene production are associated, and are discussed in relation to the hypothesis that CN- is formed during the conversion of ACC to ethylene.Abbreviations ACC
1-aminocyclopropane-1-carboxylic acid
- AVG
aminoethoxyvinylglyoine
- CAS
q6x70716677865n3/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyanoalanine synthase
- CHI
cycloheximide
- EFE
ethylene-forming enzyme 相似文献
28.
Factors affecting invertase activity in soils 总被引:7,自引:0,他引:7
Summary The rate of reducing sugars released through invertase activity exhibited a buffer pH optimum of 5.0. Generally, the decline in invertase activity in its pH-profile near the optimal pH range was due to a reversible reaction that involved ionization or deionization of the functional groups in the active centre of the protein, but under highly acidic or alkaline conditions (pH<4 to >9) the reduced activity appears to be due to irreversible inactivation of the enzyme. The dependence of the reaction on the amount of enzyme present was linear up to 3 g of soil. By varying the substrate concentration, it was found that the reaction rate of this enzyme approached zero-order kinetics when 145mM of sucrose solution was added to soils. Application of three linear transformations of the Michaelis-Menten equation indicated that the apparent Km constants varied among the soils studied, but the results obtained by the three plots were similar. By using the Lineweaver-Burk plot, the Km values in five soils ranged from 16.3 to 42.1 (avg.=24.5) mM and Vmax values ranged from 1.98 to 7.37 mg of reducing sugars released/g of soil/24 h. The optimum temperature for invertase activity in soils was observed at 50°C and denaturation of the enzyme began at 55°C. The activation energy (Ea) and enthalpy of activation (q70/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0">H*) values for invertase activity, expressed in kJ/mole, ranged from 6.1 to 43.1 and 3.5 to 40.5, respectively. The Q10 values for the invertase reaction in soils with a temperature range to 10 to 50°C ranged from 1.08 to 1.96. Under standerd conditions, the accumulation of reducing sugars was linear with time up to 48 h. Among the various pretreatments that affected invertase activity in soils, toluene, TCA, and PMA inhibited the enzyme by an average of 19, 54, and 11%, respectively. Steam-sterilization essentially destroyed soil invertase. 相似文献
29.
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