Drugs used for ovarian stimulation Clomiphene citrate, aromatase inhibitors, metformin, gonadotropins, gonadotropinreleasing hormone analogs, and recombinant gonadotropins
David K. Gardner, Ariel Weissman, Colin M. Howles, Zeev Shoham in Textbook of Assisted Reproductive Techniques, 2017
CC is a triphenylchloroethylene derivative in which the four hydrogen atoms of the ethylene core have been substituted with three phenyl rings and a chloride anion. One of the three phenyl rings bears an aminoalkoxy (OCH2– CH2–N[C2K2]2) side chain, but the importance of its action on CC remains uncertain. The dihydrogen citrate moiety (C6H8O7) accounts for the fact that commercially available preparations represent the dihydrogen citrate salt form of CC. CC is a white or pale yellow odorless powder, unstable in air and light, with a melting point of 116–118°C. It is a triarylethylene compound (1-p-diethyl aminoethoxyphenyl-1,2-diphenyl-2-chloroethylene citrate, with a molecular weight of 598.09) that is chemically related to chlorotrianisene, which is a weak estrogen. Structurally, CC is related to diethylstilbestrol, a potent synthetic estrogen. Although this compound is not a steroid, but a triphenylchloroethylene, its steroic configuration bears a remarkable structural similarity to estradiol, and consequently facilitates binding to estrogen receptors (ERs).
Natural Preservatives
Philip A. Geis in Cosmetic Microbiology, 2020
Citric acid can be found in citrus extracts. Citric acid is widely used as an acidulent in creams and gels. It also has chelating activity, which may contribute some portion of its antimicrobial activity. Benzoic acid occurs naturally in many plants and is found in many berries, particularly cranberries. Benzoic acid and its salts and esters find usage in the formulation of oral products, including toothpastes, mouthwashes and dentifrices. It is also used in creams and lotions when these products are formulated with a sufficiently low pH to elicit antimicrobial activity. Sorbic acid was first isolated from the berries of Sorbus aucuparia (the Rowan tree), from which it derives its common name. Salicylic acid is found in a number of plant materials. Its most prominent natural source is willow bark extract.
Acetazolamide
Stanley R. Resor, Henn Kutt in The Medical Treatment of Epilepsy, 2020
Six (43%) of the 14 patients with JME whom we treated with AZM monotherapy developed renal calculi (34). This finding is difficult to explain. There was no correlation between dose and the development of stones (34). Lombroso and Fbrxythe (5), who primarily treated children, reported only one stone (in a 20-year-old man) in a group of 277 patients. Griggs et al. (55) did not report any stones in 12 patients (average age, 29) with hypokalemic periodic paralysis who were treated with an average daily dose of 615 mg of AZM for about a year and a half. Kass et al. reported an incidence as high as 12% in patients with glaucoma (67). Chronic AZM therapy decreases urinary citrate, a factor that may be part of the mechanism of stone formation (67). Citrate supplementation appears to help prevent stone formation (68).
L445P mutation on heavy chain stabilizes IgG4 under acidic conditions
Published in mAbs, 2019
Chang-Ai Xu, Andrew Z. Feng, Charan K. Ramineni, Matthew R. Wallace, Elizabeth K. Culyba, Kevin P. Guay, Kinjal Mehta, Robert Mabry, Stephen Farrand, Jin Xu, Jianwen Feng
We also evaluated both acetate and citrate buffers at pH 3.5 for the low pH hold, and the data showed that citrate induces significantly more IgG4_CDR-X HC C-terminal fragmentation and aggregation than acetate. These results are consistent with other studies regarding the potential effects of citrate and acetate buffer on IgG aggregation.20 Citrate is a trivalent chemical containing three carboxylic acids with pKas of 3.1, 4.8, and 6.4, which results in high ionic strength. Acetate has only one carboxyl group with a pKa of about 4.8, which results in weaker ionic strength. Both citrate and acetate19 interact with proteins through their negative charge, thus the effect of their specific ion on protein stability is due to differences in ion strength. It was proposed20 that citrate ions preferentially accumulate near the surface of an antibody more than acetate ions, decreasing apparent conformational stability and increasing aggregation rates. Alternatively, accumulation of citrate ions is causing weaker electrostatic repulsions between proteins under low ionic strength environment, resulting in increased aggregation. Therefore, we promote use of acetate buffer rather than citrate in ProA purification processes.
Recent advances in the metabolomic study of bladder cancer
Published in Expert Review of Proteomics, 2019
Chandra Sekhar Amara, Venkatrao Vantaku, Yair Lotan, Nagireddy Putluri
One possible lipid alteration is a change in citrate concentrations, which is found to be downregulated in urine and serum of BLCA patients [58,60,61,65]. Tumor cells were observed to actively uptake nutrients from extracellular medium to synthesize citrate. The synthesized citrate is actively converted to acetyl-CoA that is utilized for fatty acid synthesis [80]. Similar to quantification and measurement of metabolites, lipids can also be measured using the mass spectrometry platform. Piyarathna et al. performed the first ever lipidomics study on pathologically confirmed BLCA tissues and identified alterations in different classes of lipids such as phosphocholines (PCs), phosphatidylethanolamines, plasmenyls PEs and triglycerides (TGs) between benign and BLCA [81]. Mapping of these altered lipids to corresponding genes and integrating with transcriptomics from TCGA resulted in a gene signature which is significantly associated with BLCA patient survival [81]. Two recent studies performed lipid profiling on BLCA cell lines and reported distinct cisplatin resistant alterations in lipidome [82,83]. One of the studies used UPLC-MS platform and reported increased lipid production in a cisplatin-resistant cell line, indicating altered lipid metabolism can be taken into account for analyzing drug resistance [82].
Clot activators and anticoagulant additives for blood collection. A critical review on behalf of COLABIOCLI WG-PRE-LATAM
Published in Critical Reviews in Clinical Laboratory Sciences, 2021
G. Lima-Oliveira, L. M. Brennan-Bourdon, B. Varela, M. E. Arredondo, E. Aranda, S. Flores, P. Ochoa
Sodium citrate is commonly used as a solution of dihydrate trisodium citrate. It is a nontoxic anticoagulant that converts Ca++ ions to the non-ionized form and prevents coagulation (Figure 4) [92]. In the clinical laboratory, it is employed mainly for preventing blood coagulation for hemostasis testing, platelet studies, and erythrocyte sedimentation rate. While additives may be liquid or dry, the latter form is preferable because the water of the liquid additives can diffuse out the plastic and jeopardize the blood/additive ratio. However, buffered sodium citrate is available only in liquid form. Therefore, manufacturers of evacuated tubes have developed a “double wall” tube system to avoid water loss and to maintain the quality of their product. Briefly the sodium citrate used in evacuated tubes has a pH ∼ 5.8 that requires approximately −40 °C in the crystallization phase of lyophilization, making the process of lyophilization of this additive in evacuated tubes impractical [93].
Related Knowledge Centers
- Acidifier
- Biochemistry
- Organic Acid
- Organic Compound
- Metabolism
- Citric Acid Cycle
- Chemical Formula
- Acid Strength
- Aerobic Organism
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