Growth and differentiation of Tubularia cells in a chemically defined physiological medium

Development ◽  
1968 ◽  
Vol 20 (1) ◽  
pp. 73-80
Author(s):  
Allison L. Burnett ◽  
Faith E. Ruffing ◽  
June Zongker ◽  
Anna Necco
Keyword(s):  
Defined Medium ◽  
Control Mechanisms ◽  
Mucous Cells ◽  
Chemically Defined Medium ◽  
Experimental Animals ◽  
Molecular Weights ◽  
Large Numbers ◽  
High Degree ◽  
I Cells

Although hydroids have proven valuable experimental animals for studies involving polarity and regeneration, they have not been extensively used by chemical embryologists studying control mechanisms in differentiation. Ideally, hydroids should be valuable tools for such a study. Their morpohology is relatively simple since they are diploblastic; their cells achieve a high degree of specialization (cnidoblasts, nerve cells, gland and mucous cells); cell differentiation (and morphogenesis) from a reserve stock of interstitial or i-cells is rapid; and many species can be cultured in large numbers under controlled environmental conditions. Probably one of the reasons for this lack of attention is that no one has succeeded in cloning cells of a particular type in a chemically defined medium. In vivo systems, mainly because of their impermeability to most exogenous materials with molecular weights over 200, have not proven to be especially reliable.

RNA, PROTEIN AND DNA SYNTHESIS STIMULATED BY TESTOSTERONE, INSULIN AND PROLACTIN IN THE RAT VENTRAL PROSTATE CULTURED IN CHEMICALLY DEFINED MEDIUM

1975 ◽  
Vol 80 (4) ◽  
pp. 761-774 ◽  
Author(s):  
Risto Johansson
Keyword(s):  
Response Times ◽  
Defined Medium ◽  
Ventral Prostate ◽  
Chemically Defined Medium ◽  
Physiological Concentration ◽  
Rat Ventral Prostate ◽  
Organ Type ◽  
High Concentrations ◽  
H Protein

ABSTRACT In an organ type tissue culture of the rat ventral prostate in a chemically defined medium insulin (0.08 IU/ml) stimulated the synthesis of RNA within 6–12 h, the synthesis of protein within 6–12 h and the synthesis of DNA within 2–4 days. Testosterone (10−8 m) stimulated these synthetic processes somewhat more slowly: the synthesis of RNA within 12–24 h, protein within 12–24 h and DNA at 4 days. Rather high concentrations of insulin were needed while testosterone was effective at a physiological concentration. Prolactin (1000 ng/ml) stimulated the synthesis of RNA and protein, but not DNA, when added together with either testosterone or insulin, but was completely ineffective when added alone. The response times resembled those of insulin. The lower concentrations of prolactin were ineffective. Growth hormone, luteinizing hormone and follicle stimulating hormone did not stimulate the synthesis of RNA, protein or DNA even when added with testosterone. The results confirm the findings of the numerous in vivo experiments that the hypophyseal hormone prolactin has a direct effect on the ventral prostate.

Effects of PGF2α and indomethacin on ovulation and steroid production in the isolated perfused rabbit ovary

1983 ◽  
Vol 104 (2) ◽  
pp. 233-239 ◽  
Author(s):  
Paul V. Holmes ◽  
Per O. Janson ◽  
Jan Sogn ◽  
Björn Källfelt ◽  
William J. LeMaire ◽  
...  
Keyword(s):  
Ovulation Induction ◽  
Defined Medium ◽  
The Other ◽  
Chemically Defined Medium ◽  
Perfusion Medium ◽  
Steroid Production ◽  
Experimental Side ◽  
Series Of Experiments

Abstract. Both ovaries of 31 rabbits were perfused with a chemically defined medium in vitro in a recirculation system. In one series of experiments, hCG (100 IU) was injected iv 5–6 h prior to anaesthesia and surgery. Approximately 1 h later the perfusion was started. One ovary was perfused as control while the other ovary was perfused with 5 μg/ml indomethacin or with indomethacin and 1 μg/ml PGF2α. In another series of experiments the rabbits received no pretreatment prior to operation. Instead, bovine LH was added to the perfusion medium of both control and experimental ovaries. The experimental side also received either indomethacin or indomethacin and PGF2α. Finally, the effect of PGF2α in the absence of LH was compared to the control ovary receiving only LH. After injection of hCG in vivo, ovulations occurred in 4 of 5 control ovaries. Indomethacin completely blocked ovulation in 4 of the 5 ovaries treated, while PGF2α restored ovulations in all the experimental ovaries. In the group of experiments where LH was added in vitro, ovulations were induced in all ovaries treated with varying LH doses. Furthermore, indomethacin blocked ovulation in 5 out of 7 ovaries, and PGF2α restored ovulation in all ovaries. Fifty per cent of the ovaries treated only with PGF2α (in the absence of LH) also ovulated. The pattern of steroid release did not differ between control ovaries, indomethacin treated ovaries, and indomethacin + PGF2α treated ovaries. Ovaries treated in perfusion with PGF2α alone had very low steroid levels compared to the ovaries treated with LH. This study confirms that indomethacin blocks ovulation in the perfused rabbit ovary and that this blockade can be overcome by exogenous PGF2α. Indomethacin and PG-treatments after ovulation induction did not affect ovarian steroidogenesis. Furthermore, while PGF2α was able to induce ovulations in these perfused oestrous ovaries in the absence of LH, it did not stimulate steroidogenesis.

scholarly journals Unique Host Iron Utilization Mechanisms of Helicobacter pylori Revealed with Iron-Deficient Chemically Defined Media

2010 ◽  
Vol 78 (5) ◽  
pp. 1841-1849 ◽  
Author(s):  
Olga Senkovich ◽  
Shantelle Ceaser ◽  
David J. McGee ◽  
Traci L. Testerman
Keyword(s):  
Helicobacter Pylori ◽  
Defined Medium ◽  
Normal Serum ◽  
Chemically Defined Medium ◽  
Limited Growth ◽  
Defined Media ◽  
Iron Deficient ◽  
Novel Strategy ◽  
H Pylori

ABSTRACT Helicobacter pylori chronically infects the gastric mucosa, where it can be found free in mucus, attached to cells, and intracellularly. H. pylori requires iron for growth, but the sources of iron used in vivo are unclear. In previous studies, the inability to culture H. pylori without serum made it difficult to determine which host iron sources might be used by H. pylori. Using iron-deficient, chemically defined medium, we determined that H. pylori can bind and extract iron from hemoglobin, transferrin, and lactoferrin. H. pylori can use both bovine and human versions of both lactoferrin and transferrin, contrary to previous reports. Unlike other pathogens, H. pylori preferentially binds the iron-free forms of transferrin and lactoferrin, which limits its ability to extract iron from normal serum, which is not iron saturated. This novel strategy may have evolved to permit limited growth in host tissue during persistent colonization while excessive injury or iron depletion is prevented.

Vitrification and warming of in vivo–derived porcine embryos in a chemically defined medium

2010 ◽  
Vol 73 (3) ◽  
pp. 300-308 ◽  
Author(s):  
J. Sanchez-Osorio ◽  
C. Cuello ◽  
M.A. Gil ◽  
I. Parrilla ◽  
C. Maside ◽  
...  
Keyword(s):  
Defined Medium ◽  
Chemically Defined Medium

scholarly journals Precocious development of uridine diphosphate glucuronosyltransferase activity during organ culture of foetal rat liver in the presence of glucocorticoids

1977 ◽  
Vol 166 (2) ◽  
pp. 249-253 ◽  
Author(s):  
G J Wishart ◽  
M A Goheer ◽  
J E A Leakey ◽  
G J Dutton
Keyword(s):  
Rat Liver ◽  
Defined Medium ◽  
Transferase Activity ◽  
Uridine Diphosphate ◽  
Chemically Defined Medium ◽  
Foetal Rat ◽  
First Time ◽  
Precocious Development ◽  
Stimulation Of

1. Precocious development of mammalian UDP-glucuronosyltransferase (EC 2.4.1.1.7) induced by endogenous compounds of known chemical composition is reported for the first time. 2. This development occurs in cultured explants of foetal rat liver when exposed to corticosteroids possessing a pregn-4′-ene structure and a hydroxy or an oxo group at C-11. 3. Explants from 14-day foetuses cultured for 3 days in a chemically defined medium containing dexamethasone exhibited transferase activities towards o-aminophenol within adult male values. Those liver transferase activities attained in utero by 17 days were still negligible. 4. Evidence from several approaches indicated that the explants required glucocorticoids for expression of the transferase, not for maintenance of viability. 5. Glucocorticoid-dependent stimulation of transferase activity required incorporation of L-[14C]leucine into protein, as judged from the pulsing of cultures with cycloheximide. 6. The relevance of these culture experiments to the situation in vivo is discussed.

scholarly journals Thyroxine is the serum factor that regulates morphogenesis of columnar cartilage from isolated chondrocytes in chemically defined medium.

1994 ◽  
Vol 126 (5) ◽  
pp. 1311-1318 ◽  
Author(s):  
R T Ballock ◽  
A H Reddi
Keyword(s):  
Alkaline Phosphatase ◽  
Serum Concentration ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Critical Role ◽  
Three Dimensional ◽  
Defined Medium ◽  
Chemically Defined Medium ◽  
Type X Collagen

Epiphyseal chondrocytes cultured in a medium containing 10% serum may be maintained as three dimensional aggregates and differentiate terminally into hypertrophic cells. There is an attendant expression of genes encoding type X collagen and high levels of alkaline phosphatase activity. Manipulation of the serum concentration to optimal levels of 0.1 or 0.01% in this chondrocyte pellet culture system results in formation of features of developing cartilage architecture which have been observed exclusively in growth cartilage in vivo. Cells are arranged in columns radiating out from the center of the tissue, and can be divided into distinct zones corresponding to the recognized stages of chondrocyte differentiation. Elimination of the optimal serum concentration in a chemically defined medium containing insulin eliminates the events of terminal differentiation of defined cartilage architecture. Chondrocytes continue to enlarge into hypertrophic cells and synthesize type X collagen mRNA and protein, but in the absence of the optimal serum concentration, alkaline phosphatase activity does not increase and the cells retain a random orientation. Addition of thyroxine to the chemically defined medium containing insulin and growth hormone results in dose-dependent increases in both type X collagen synthesis and alkaline phosphatase activity, and reproduces the optimal serum-induced morphogenesis of chondrocytes into a columnar pattern. These experiments demonstrate the critical role of thyroxine in cartilage morphogenesis.

The preovulatory decline in follicular oestradiol is not required for ovulation in the rabbit

1982 ◽  
Vol 101 (3) ◽  
pp. 452-457 ◽  
Author(s):  
William J. LeMaire ◽  
Per O. Janson ◽  
Björn J. Källfelt ◽  
Paul V. Holmes ◽  
Stefan Cajander ◽  
...  
Keyword(s):  
Follicular Fluid ◽  
Defined Medium ◽  
Chemically Defined Medium ◽  
In Vitro Perfusion ◽  
Control Side ◽  
Recirculation System

Abstract. Using a method of in vitro perfusion of the rabbit ovary with a chemically defined medium in a recirculation system, normal appearing follicular ruptures occurred following exposure of the ovaries to hCG in vivo (100 IU) or following addition of LH (0.25 μg/ml of NIH B9) to the perfusate. The addition of oestradiol17β (10 μg/ml) to the perfusate did not inhibit these follicular ruptures, although the follicular fluid oestradiol contents were increased more than 100-fold as compared to the control side not receiving the addition of oestradiol. These data suggest that the physiological decline of follicular oestrogen, normally observed in vivo prior to ovulation in the rabbit, is not required as part of the mechanism of ovulation and that normal appearing ovulations can occur even though follicular oestrogen levels are kept artificially elevated.

The synthesis of a variant-specific antigen by Trypanosoma brucei in vitro

Parasitology ◽  
1977 ◽  
Vol 74 (1) ◽  
pp. 47-60 ◽  
Author(s):  
D. W. Taylor ◽  
G. A. M. Cross
Keyword(s):  
Protein Synthesis ◽  
Specific Surface ◽  
Trypanosoma Brucei ◽  
Specific Antigen ◽  
Defined Medium ◽  
Surface Coat ◽  
Chemically Defined Medium ◽  
Inhibit Protein Synthesis

A variant-specific surface antigen from a cloned population of Trypanosoma brucei S 42 has been isolated and partically characterized. [35S]L-methionine was found to be incorporated into this material by cells incubated in vitro in a chemically defined medium. Incorporation of [35S]L-methionine was inhibited by cycloheximide and puromycin at concentrations which are known to specifically inhibit protein synthesis in other systems. The rate of synthesis of the variant-specific antigen in vitro has been estimated to be about 8% of the rate in vivo. Newly synthesized [35S]L-methionine-labelled variant-specific antigen was incorporated into the surface coat.

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