EFFECT OF PROPYLTHIOURACIL ON THE IODINATION AND MATURATION OF RAT THYROGLOBULIN

1966 ◽  
Vol 53 (2) ◽  
pp. 271-285 ◽  
Author(s):  
Claude Simon ◽  
Marie Roques ◽  
Janine Torresani ◽  
Serge Lissitzky

ABSTRACT The effect of propylthiouracil on the maturation of rat thyroglobulin in vivo has been investigated. Newly iodinated thyroglobulin dimer is labile to freezing and thawing. This observation has been used to interpret the findings in the present experiments. From experiments using rats in isotopic equilibrium with 125I, and treated with propylthiouracil or propylthiouracil and tri-iodothyronine and also given a single injection of 131I, the following conclusions were formulated 1) the appearance of iodinated S12 thyroglobulin monomer is due to the dissociation of labile iodinated thyroglobulin dimer and appears more readily if the dimer is poorly iodinated, 2) uniodinated thyroglobulin dimer is the most probable substrate for iodination in vivo, 3) maturation of thyroglobulin dimer (as shown by increasing sedimentation constant from 16—17 to 19) is accompanied by increasing amounts of iodine in the molecule, 4) it is not possible to say at present if iodination and iodothyronine formation is the cause or the consequence of thyroglobulin dimer maturation, 5) propylthiouracil might inhibit thyroglobulin maturation by decreasing iodine organification.

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S649-S649
Author(s):  
Laurent Besret ◽  
Jean-Dominique Gallezot ◽  
Frédéric Dollé ◽  
Philippe Hantraye ◽  
Marie-Claude Grégoire

1979 ◽  
Vol 92 (4) ◽  
pp. 731-745
Author(s):  
Jørgen Jørgensen

ABSTRACT The marked renin inactivation seen during in vitro incubation of post-partum uterine slices which mimics the in vivo condition, is not accompanied by a similar general proteolysis. The inactivating mechanism is so far non-specific with respect to organ or species as added hog renal renin is inactivated at a similar rate as endogenous renin. Endogenous alkaline phosphatase is not significantly inactivated and added alkaline phosphatase is completely stable. A marked inactivation of endogenous renin also takes place during incubation of a mixed mitochondrial-lysosomal suspension prepared from post-partum uterus. The process is more pronounced at pH 7.4 than at 6.8. Freezing and thawing and addition of Triton X-100 prior to incubation inhibits the inactivation. ATP and α-ketoglutarate slightly stimulates the process while CoA and chloroquine have no effect. Both iodoacetate and phenylmethylsulphonylfluoride inhibit the inactivation, suggesting that more than one enzyme is involved in the inactivation.


1985 ◽  
Vol 231 (1) ◽  
pp. 165-169 ◽  
Author(s):  
E Karvonen ◽  
L Kauppinen ◽  
T Partanen ◽  
H Pösö

The putrescine-stimulated S-adenosyl-L-methionine decarboxylases from rat liver and yeast were strongly inhibited by Berenil and to a lesser extent by Pentamidine. Ten times greater drug concentrations were needed to achieve a similar level of inhibition of a Mg2+-stimulated bacterial enzyme. The inhibition was irreversible in that extensive dialyses or precipitation with (NH4)2SO4 did not restore enzyme activity. Putrescine did not protect the enzyme against Berenil, but adenosylmethionine either alone or with putrescine partially protected the irreversible action of Berenil. The compound 4,4′-diamidinodiphenylamine, which differs from Berenil only in lacking the azo group between benzene rings, was a weaker inhibitor than Berenil, and its inhibition was reversible. Berenil also inhibited the activity of adenosylmethionine decarboxylase in vivo, by depressing the activity of the enzyme in normal rat liver, for at least 24 h after a single injection (50 mg/kg body wt.) of the drug.


2000 ◽  
Vol 113 (5) ◽  
pp. 767-778 ◽  
Author(s):  
A. Delplanque ◽  
C. Coraux ◽  
R. Tirouvanziam ◽  
I. Khazaal ◽  
E. Puchelle ◽  
...  

We have developed an in vivo assay for progenitor cells of the human tracheobronchial epithelium relying on the transplantation of human prenatal respiratory tissues into severe combined immunodeficiency mice. Engrafted embryonic or fetal open tracheobronchial rudiments are rapidly closed at each end by a neoformed membrane that we named the operculum. After 2–4 weeks, differentiated human respiratory epithelium covers both the native airway matrix and the new operculum. Human epithelial cells dissociated from either emerging embryonic lung primordia or mature xenografts were seeded in host human airway grafts, of which native epithelium had been eliminated by several cycles of freezing and thawing. All grafts seeded with donor epithelial cells and implanted back into SCID mice recovered a surface mucociliary epithelium expressing expected markers and secreting mucus. Spontaneous epithelium regrowth was never observed in control unseeded, denuded grafts. In some experiments, donor epithelial cells and host denuded airway were sex-mismatched and the donor origin of newly formed epithelial structures was confirmed by sex chromosome detection. After two rounds of seeding and reimplantation, a normal epithelium was observed to line the 3rd generation operculum. These observations substantiate a functional assay for human candidate airway epithelium stem cells.


1994 ◽  
Vol 267 (6) ◽  
pp. G1128-G1134 ◽  
Author(s):  
M. A. Dudley ◽  
F. Jahoor ◽  
D. G. Burrin ◽  
P. J. Reeds

Conscious unrestrained piglets were fasted overnight and infused intravenously with [2H3]leucine for 6 h. Sucrase isomaltase and lactase phlorizin hydrolase were immunoprecipitated from jejunal mucosal membranes, and the immunoprecipitates were electrophoresed on polyacrylamide gels. Bands corresponding to the pro and mature isoforms of both enzymes were acid hydrolyzed. [2H3]leucine isotopic enrichment was measured by gas chromatography-mass spectrometry using negative chemical ionization. Plasma leucine reached isotopic steady state within 90 min. The isotopic enrichment of mucosal leucine was 73% of that of plasma leucine. The high mannose and complex glycosylated forms of prolactase were in isotopic equilibrium, and their isotopic enrichment was 94% of mucosal leucine. The fractional synthesis rates of total and membrane protein were 0.45 and 0.65 days-1, whereas the processing rates of mature lactase, sucrase, and isomaltase were 0.90, 0.23, and 0.21 days-1, respectively. Approximately 65% of the label in the sucrase isomaltase immunoprecipitate was in the complex glycosylated precursor, whereas 73% of the label in lactase phlorizin hydrolase was in the mature (160 kDa) form. We conclude that the low rate of brush-border sucrase synthesis reflects a slow rate at which the complex glycosylated precursor is processed to the brush-border form.


2016 ◽  
Vol 28 (2) ◽  
pp. 227
Author(s):  
M. Nõmm ◽  
E. Mark ◽  
O. Sarv ◽  
S. Kõks ◽  
Ü. Jaakma

Over a few decades the bovine in vitro embryo production (IVP) systems have been improving rapidly. Still, the goal to produce the same quality embryos in vitro as in vivo has not yet been reached. The FCS is usually added to media during IVP to provide growth factors and energy sources. Currently, serum-free culture systems are often preferred due to the lower risk of contamination and prevention of the development of large offspring syndrome. The aim of this study was to establish whether complete elimination of FCS from the bovine IVP system has an effect on blastocyst rates, embryo quality, and embryo survival rates after slow freezing. We replaced our conventional in vitro maturation (IVM) medium [tissue culture medium-199, 10% (v/v) FCS, 10 µg mL–1 epidermal growth factor (EGF), 1500 U mL–1 serum gonadotropin and chorionic gonadotropin (PG600), Na-pyruvate 0.5 mM, gentamycin sulfate 50 µg mL–1 and l-glutamine 1 mM] with SOF (SOFaaci) supplemented with 0.4% fatty acid-free BSA fraction V, 10 µg mL–1 EGF, and 1500 U mL–1 PG600. Matured cumulus-oocyte complexes (COC) from both experimental groups (total of 1145 from serum-free IVP and 687 from our conventional IVP system) were used for in vitro fertilisation and culture. Blastocyst rates were similar in the serum-free and our usual IVP protocol, 18 and 22%, respectively. Seventy-seven Grade 1 (according to IETS) Day 7 blastocysts from the serum-free IVP system and 80 Grade 1 Day 7 blastocysts from our conventional IVP system were frozen in 1.5 M ethylene glycol and 0.1 M sucrose containing cryopreservation medium. The post-thaw survival rates after 24 h of culture and evaluated as percentages of re-expanded embryos were 63.6% for the serum-free IVP and 46.3% for the conventional IVP system (P < 0.05, Z Test for 2 population proportions). These results indicate that it is possible to have a completely serum-free bovine IVP system and based on the slow freezing and thawing results the quality of serum-free IVP embryos might be better than of the embryos matured in our conventional maturation media. However, more experiments and increased sample sizes are needed to confirm the results. This study was supported by Project 3.2.0701.12–0036 of Archimedes Foundation, AP 2.4 of CCRMB, and institutional research funding (IUT 08–01) of the Estonian Ministry of Education and Research.


1962 ◽  
Vol 40 (12) ◽  
pp. 1819-1838 ◽  
Author(s):  
Walter H. E. Roschlau ◽  
Robert H. Painter

The lytic effects of heat-treated, sterile solutions of spontaneously activated and urokinase-activated fibrinolysin on occlusive experimental arterial clots have been studied. For this purpose methods for the preparation of urokinase and activation of profibrinolysin, the production of traumatic arterial thrombi in dogs, and the recording of clot lysis are described. Single injection as a means of administration was compared with the traditional method of infusion. When used in conjunction with a prompt assay of the in vivo fibrinolytic activity, which was developed for this purpose, the injection method was preferred. The results indicated that spontaneous fibrinolysin, given by single injection, was as effective in lysing clots as were preparations of fibrinolysin that contained activator. The approximate therapeutic dose for both types of fibrinolysin under the conditions described was found to be 225–325 Michigan Department of Health caseinolytic units per kg body weight. Lysis of occluding arterial thrombi was achieved within a few hours after administration of fibrinolysin by injection, and arteries remained patent during the week of posttreatment observation. No toxic effects due to the fibrinolysin or the glycerol present as stabilizer could be demonstrated after the therapeutic dose. The only undesirable side effect of overdose of fibrinolysin was a transient incoagulability of the blood.


2019 ◽  
Vol 64 (2) ◽  
Author(s):  
S. Albac ◽  
M. Medina ◽  
D. Labrousse ◽  
D. Hayez ◽  
D. Bonnot ◽  
...  

ABSTRACT This study investigated the in vivo efficacy of three bacteriophages combined compared with linezolid in two mouse models (nondiabetic and diabetic) of Staphylococcus aureus foot infection. In both models, a single injection of bacteriophages in the hindpaw showed significant antibacterial efficacy. Linezolid was as effective as bacteriophages in nondiabetic animals but ineffective in diabetic animals. These findings further support preclinical and clinical studies for the development of phage therapy.


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