scholarly journals Endogenous production of specific flavonoids and verbascoside in agar and agitated microshoot cultures of Scutellaria lateriflora L. and biotransformation potential

2020 ◽  
Vol 142 (3) ◽  
pp. 471-482 ◽  
Author(s):  
Beata Kawka ◽  
Inga Kwiecień ◽  
Halina Ekiert
Keyword(s):  
Endogenous Production ◽  
Scutellaria Lateriflora

scholarly journals Hormones in international meat production: biological, sociological and consumer issues

2002 ◽  
Vol 15 (2) ◽  
pp. 293-314 ◽  
Author(s):  
Hugh Galbraith
Keyword(s):  
Biological Activity ◽  
Adverse Effects ◽  
Good Practice ◽  
Current Status ◽  
Current Evidence ◽  
Meat Production ◽  
International Consensus ◽  
Free Radical Damage ◽  
Endogenous Production ◽  
Human Pathology

AbstractBeef and its products are an important source of nutrition in many human societies. Methods of production vary and include the use of hormonal compounds (‘hormones’) to increase growth and lean tissue with reduced fat deposition in cattle. The hormonal compounds are naturally occurring in animals or are synthetically produced xenobiotics and have oestrogenic (oestradiol-17β and its esters; zeranol), androgenic (testosterone and esters; trenbolone acetate) or progestogenic (progesterone; melengestrol acetate) activity. The use of hormones as production aids is permitted in North American countries but is no longer allowed in the European Union (EU), which also prohibits the importation of beef and its products derived from hormone-treated cattle. These actions have resulted in a trade dispute between the two trading blocs. The major concern for EU authorities is the possibility of adverse effects on human consumers of residues of hormones and metabolites. Methods used to assess possible adverse effects are typical of those used by international agencies to assess acceptability of chemicals in human food. These include analysis of quantities present in the context of known biological activity and digestive, absorptive, post-absorptive and excretory processes. Particular considerations include the low quantities of hormonal compounds consumed in meat products and their relationships to endogenous production particularly in prepubertal children, enterohepatic inactivation, cellular receptor- and non-receptor-mediated effects and potential for interference with growth, development and physiological function in consumers. There is particular concern about the role of oestradiol-17β as a carcinogen in certain tissues. Now subject to a ‘permanent’ EU ban, current evidence suggests that certain catechol metabolites may induce free-radical damage of DNA in cell and laboratory animal test systems. Classical oestrogen-receptor mediation is considered to stimulate proliferation in cells maintaining receptivity. Mathematical models describing quantitative relationships between consumption of small amounts of oestrogens in meat in addition to greater concentrations from endogenous production, chemical stoichiometry at cellular level and human pathology have not been developed. Such an approach will be necessary to establish ‘molecular materiality’ of the additional hormone intake as a component of relative risk assessment. The other hormones, although generally less well researched, are similarly subject to a range of tests to determine potentially adverse effects. The resulting limited international consensus relates to the application of the ‘precautionary principle’ and non-acceptance by the European Commission of the recommendations of the Codex Alimentarius Commission, which determined that meat from cattle, hormone-treated according to good practice, was safe for human consumers. The present review considers the hormone issue in the context of current international social methodology and regulation, recent advances in knowledge of biological activity of hormones and current status of science-based evaluation of food safety and risk for human consumers.

scholarly journals B cell stimulatory factor 1 (interleukin 4) is sufficient for the proliferation and differentiation of lectin-stimulated cytolytic T lymphocyte precursors.

1987 ◽  
Vol 166 (5) ◽  
pp. 1464-1470 ◽  
Author(s):  
J D Pfeifer ◽  
D T McKenzie ◽  
S L Swain ◽  
R W Dutton
Keyword(s):  
T Lymphocyte ◽  
Proliferative Response ◽  
Inhibitory Effect ◽  
Interleukin 4 ◽  
Con A ◽  
Endogenous Production ◽  
Proliferation And Differentiation ◽  
Cytolytic T Lymphocyte ◽  
Stimulatory Factor ◽  
Mitogenic Lectin

In this report, we demonstrate that IL-4 is sufficient to stimulate both the proliferation and differentiation of Lyt-2+, Ia- splenic CTL precursors stimulated with the mitogenic lectin Con A. The response to IL-4 and Con A was not dependent on a putative endogenous production of IL-2 within the cultures, as demonstrated by an absence of an inhibitory effect by an anti-IL-2-R blocking mAb. Our results indicate that IL-2 and IL-4 can support an equivalent proliferative response by lectin-stimulated Lyt-2+ T lymphocytes, while IL-4 is more efficacious in stimulating their differentiation into mature cytolytically active cells.

Unsaturated lipids and intestinal bacteria as sources of endogenous production of ethene and ethylene oxide

1989 ◽  
Vol 10 (1) ◽  
pp. 39-41 ◽  
Author(s):  
Margareta Törnqvist ◽  
B. Gustafsson ◽  
A. Kautiainen ◽  
M. Harms-Ringdahl ◽  
F. Granath ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Intestinal Bacteria ◽  
Unsaturated Lipids ◽  
Endogenous Production

Endogenous Production Networks under Uncertainty

2021 ◽  
Author(s):  
Alexandr Kopytov ◽  
Bineet Mishra ◽  
Kristoffer Nimark ◽  
Mathieu Taschereau-Dumouchel
Keyword(s):  
Production Networks ◽  
Endogenous Production

Abstract 3030: Differential Regulation of Valvular Interstitial Cell Dysfunction by Extracellular Matrix Components

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Karien J Rodriguez ◽  
Kristyn S Masters
Keyword(s):  
Extracellular Matrix ◽  
Transforming Growth Factor ◽  
Neutralizing Antibody ◽  
Lower Amount ◽  
Valvular Interstitial Cells ◽  
Cell Dysfunction ◽  
Endogenous Production ◽  
Extracellular Matrix Components ◽  
Culture Surface

Calcification is the leading cause of bioprosthetic and native aortic valve failure, but relatively little is known regarding the factors that contribute to the progression of valvular calcification. Because extracellular matrix (ECM) disarray is often observed in explanted diseased valves, we have investigated the role of individual ECM components in the in vitro calcification of valvular interstitial cells (VICs). The transformation of VICs to an osteoblast-like phenotype was quantified in VICs cultured on different types of ECM coatings. The results show that the number and size of calcific nodules formed in VIC cultures, as well as the expression of mineralization markers alkaline phosphatase (ALP) and CBFa1, were highly dependent upon the composition of the culture surface. In fact, VICs cultured on certain ECM components, namely collagen (Coll) and fibronectin (FN), were resistant to calcification, even upon treatment with potent mineralization-inducing growth factors, such as transforming growth factor beta1 (TGFb1). Meanwhile, VIC cultures on fibrin (FB), laminin, and heparin not only had a high number of calcified nodules (p<0.001 vs. Coll, FN), but also elevated levels of ALP and CBFa1 (p<0.02), and the number of nodules on these ‘pro-calcific’ coatings significantly increased upon treatment with exogenous TGFb1 (p<0.05). To explain the ECM-dependence of calcification, the endogenous production of a pro-mineralization factor (TGFb1) was assessed in VICs on anti-calcific (Coll) and pro-calcific (FB) substrates. Quantification of TGFb1 mRNA revealed that VICs on Coll surfaces expressed a significantly lower amount of TGFb1 mRNA than VICs on FB (p<0.01). Furthermore, treatment with a neutralizing antibody to TGFb1 decreased TGFb1 mRNA expression by VICs on Coll in comparison to VICs on FB or polystyrene controls (p<0.02). Thus, we have discovered a strong correlation between VIC calcification and ECM composition. Our findings show that the ECM plays an important role in controlling TGFb1 expression and subsequent calcification of VICs, which may significantly impact the design of biomaterials for valve tissue engineering, understanding of valvular disease, and the development of preventative treatments for valve calcification.

Studies on the Endogenous Production of Oxalate in Man

1985 ◽  
pp. 219-222
Author(s):  
B. Nordenvall ◽  
L. Backman ◽  
L. Larsson
Keyword(s):  
Endogenous Production
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