Enhanced production of human epidermal growth factor by a recombinant Escherichia coli integrated with in situ exchange of acetic acid by macroporous ion-exchange resin

2005 ◽  
Vol 100 (5) ◽  
pp. 579-581 ◽  
Author(s):  
Xin'ai Chen ◽  
Peilin Cen ◽  
Jishuang Chen
Keyword(s):  
Escherichia Coli ◽  
Acetic Acid ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Ion Exchange ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Enhanced Production ◽  
Epidermal Growth

scholarly journals Enhanced production of periplasmic interferon alpha-2b by Escherichia coli using ion-exchange resin for in situ removal of acetate in the culture

2011 ◽  
Vol 58-59 ◽  
pp. 124-132 ◽  
Author(s):  
Joo Shun Tan ◽  
Ramakrishnan Nagasundara Ramanan ◽  
Tau Chuan Ling ◽  
Mustafa Shuhaimi ◽  
Arbakariya B. Ariff
Keyword(s):  
Escherichia Coli ◽  
Ion Exchange ◽  
Interferon Alpha ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Interferon Alpha 2B ◽  
Enhanced Production

scholarly journals Kinetics of soybean oil epoxidation with peracetic acid formed in situ in the presence of an ion exchange resin: Pseudo-homogeneous model

2017 ◽  
Vol 23 (1) ◽  
pp. 97-111 ◽  
Author(s):  
Milovan Jankovic ◽  
Snezana Sinadinovic-Fiser ◽  
Olga Govedarica ◽  
Jelena Pavlicevic ◽  
Jaroslava Budinski-Simendic
Keyword(s):  
Acetic Acid ◽  
Ion Exchange ◽  
Soybean Oil ◽  
Peracetic Acid ◽  
Exchange Resin ◽  
Homogeneous Model ◽  
Ion Exchange Resin ◽  
Rate Coefficients ◽  
Epoxy Ring

A kinetic model was proposed for the epoxidation of vegetable oils with peracetic acid formed in situ from acetic acid and hydrogen peroxide in the presence of an acidic ion exchange resin as a catalyst. The model is pseudo-homogeneous with respect to the catalyst. Besides the main reactions of peracetic acid and epoxy ring formation, the model takes into account the side reaction of epoxy ring opening with acetic acid. The partitioning of acetic acid and peracetic acid between the aqueous and organic phases and the change in the phases? volumes during the process were considered. The temperature dependency of the apparent reaction rate coefficients is described by a reparameterized Arrhenius equation. The constants in the proposed model were estimated by fitting the experimental data obtained for the epoxidations of soybean oil conducted under defined reaction conditions. The highest epoxy yield of 87.73% was obtained at 338 K when the mole ratio of oil unsaturation:acetic acid:hydrogen peroxide was 1:0.5:1.35 and when the amount of the catalyst Amberlite IR-120H was 4.04 wt.% of oil. Compared to the other reported pseudo-homogeneous models, the model proposed in this study better correlates the change of double bond and epoxy group contents during the epoxidation process.

Apoptosis in human cultured trophoblasts is enhanced by hypoxia and diminished by epidermal growth factor

2000 ◽  
Vol 278 (5) ◽  
pp. C982-C988 ◽  
Author(s):  
Roni Levy ◽  
Steven D. Smith ◽  
Kala Chandler ◽  
Yoel Sadovsky ◽  
D. Michael Nelson
Keyword(s):  
Cell Differentiation ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Fetal Growth ◽  
Fetal Growth Restriction ◽  
Caspase Inhibitor ◽  
Trophoblast Differentiation ◽  
Epidermal Growth ◽  
Induced Apoptosis

Preeclampsia and fetal growth restriction are associated with placental hypoperfusion and villous hypoxia. The villous response to this environment includes diminished trophoblast differentiation and enhanced apoptosis. We tested the hypothesis that hypoxia induces apoptosis in cultured trophoblasts, and that epidermal growth factor (EGF), an enhancer of trophoblast differentiation, diminishes hypoxia-induced apoptosis. Trophoblasts isolated from placentas of term-uncomplicated human pregnancies were cultured up to 72 h in standard ([Formula: see text]= 120 mmHg) or hypoxic ([Formula: see text] < 15 mmHg) conditions. Exposure to hypoxia for 24 h markedly enhanced trophoblast apoptosis as determined by DNA laddering, internucleosomal in situ DNA fragmentation, and histomorphology, as well as by the reversibility of the apoptotic process with a caspase inhibitor. Apoptosis was accompanied by increased expression of p53 and Bax and decreased expression of Bcl-2. Addition of EGF to cultured trophoblasts or exposure of more differentiated trophoblasts to hypoxia significantly lowered the level of apoptosis. We conclude that hypoxia enhances apoptosis in cultured trophoblasts by a mechanism that involves an increase in p53 and Bax expression. EGF and enhancement of cell differentiation protect against hypoxic-induced apoptosis.

Production of Epidermal Growth Factor in Escherichia Coli from a Synthetic Gene

1985 ◽  
Vol 1985 (Supplement 3) ◽  
pp. 29-38 ◽  
Author(s):  
G. ALLEN ◽  
C. A. PAYNTER ◽  
M. D. WINTHER
Keyword(s):  
Escherichia Coli ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Synthetic Gene ◽  
Epidermal Growth

scholarly journals Epidermal Growth Factor Inhibits Campylobacter jejuni-Induced Claudin-4 Disruption, Loss of Epithelial Barrier Function, and Escherichia coli Translocation

2008 ◽  
Vol 76 (8) ◽  
pp. 3390-3398 ◽  
Author(s):  
Jennifer M. Lamb-Rosteski ◽  
Lisa D. Kalischuk ◽  
G. Douglas Inglis ◽  
Andre G. Buret
Keyword(s):  
Escherichia Coli ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Campylobacter Jejuni ◽  
Egf Receptor ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Epithelial Barrier Function ◽  
Epidermal Growth

ABSTRACT Campylobacter jejuni is a leading cause of acute bacterial enteritis in humans. Poultry serves as a major reservoir of C. jejuni and is thought to act as a principal vehicle of transmission to humans. Epidermal growth factor (EGF) is a small amino acid peptide that exerts a broad range of activities on the intestinal epithelium. The aims of this study were to determine the effect of EGF on C. jejuni intestinal colonization in newly hatched chicks and to characterize its effects on C. jejuni-induced intestinal epithelial barrier disruption. White Leghorn chicks were treated with EGF daily, starting 1 day prior to C. jejuni infection, and were compared to control and C. jejuni-infected, EGF-treated chicks. Infected chicks shed C. jejuni in their feces throughout the study period. C. jejuni colonized the small intestine and cecum, disseminated to extraintestinal organs, and caused jejunal villus atrophy. EGF reduced jejunal colonization and dissemination of C. jejuni to the liver and spleen. In EGF-treated C. jejuni-infected chicks, villus height was not significantly different from that in untreated C. jejuni-infected chicks or controls. In vitro, C. jejuni attached to and invaded intestinal epithelial cells, disrupted tight junctional claudin-4, and increased transepithelial permeability. C. jejuni also promoted the translocation of noninvasive Escherichia coli C25. These C. jejuni-induced epithelial abnormalities were abolished by pretreatment with EGF, and the effect was dependent upon activation of the EGF receptor. These findings highlight EGF's ability to alter colonization of C. jejuni in the intestinal tract and to protect against pathogen-induced barrier defects.

scholarly journals Ion-exchange-resin-catalyzed adamantylation of phenol derivatives with adamantanols: Developing a clean process for synthesis of 2-(1-adamantyl)-4-bromophenol, a key intermediate of adapalene

2012 ◽  
Vol 8 ◽  
pp. 227-233 ◽  
Author(s):  
Nan Wang ◽  
Ronghua Wang ◽  
Xia Shi ◽  
Gang Zou
Keyword(s):  
Acetic Acid ◽  
Ion Exchange ◽  
Sulfonic Acid ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Phenol Derivatives ◽  
Resin Catalyst ◽  
Acid Resin ◽  
Free Process ◽  
Sulfonic Acid Resin

A clean process has been developed for the synthesis of 2-adamantylphenol derivatives through adamantylation of substituted phenols with adamantanols catalyzed by commercially available and recyclable ion-exchange sulfonic acid resin in acetic acid. The sole byproduct of the adamantylation reaction, namely water, could be converted into the solvent acetic acid by addition of a slight excess of acetic anhydride during the work-up procedure, making the process waste-free except for regeneration of the ion-exchange resin, and facilitating the recycling of the resin catalyst. The ion-exchange sulfonic acid resin catalyst could be readily recycled by filtration and directly reused at least ten times without a significant loss of activity. The key intermediate of adapalene, 2-(1-adamantyl)-4-bromophenol, could be produced by means of this waste-free process.

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