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1.
Aquat Toxicol ; 179: 8-17, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27541482

ABSTRACT

Endocrine active compounds (EACs) remain an important group of chemicals that require additional evaluation to determine their environmental impacts. While estrogens and androgens were previously demonstrated to impact organisms during environmental exposures, progestagens have recently been shown to have strong impacts on aquatic organisms. To gain an understanding of the impacts of these types of chemicals on aquatic species, experiments evaluating the mechanisms of action of progestagen exposure were conducted with the Eastern Mosquitofish (Gambusia holbrooki). The objective of this study was to conduct hepatic microarray analysis of male and female G. holbrooki exposed to progestins and anti-progestagens. In addition, we evaluated the ability of levonorgestrel, a synthetic progesterone (progestin), to induce anal fin elongation and to determine how anal fin growth is modulated during co-exposures with progesterone and androgen receptor antagonists. Gene expression analyses were conducted on male and female G. holbrooki exposed for 48h to the agonist levonorgestrel, the antagonist mifepristone, or a mixture of the two chemicals. Microarray analysis revealed that mifepristone does not act as an anti-progestagen in G. holbrooki in liver tissues, and that levonorgestrel elicits strong effects on the processes of embryo development and lipid transport. Levonorgestrel was also demonstrated to induce male secondary sexual characteristic formation in females, and co-exposure of either an androgen or levonorgestrel in the presence of the anti-androgen flutamide prevented anal fin elongation. These results provide indications as to the potential impacts of progestins, including non-target effects such as secondary sexual characteristic formation, and demonstrate the importance of this class of chemicals on aquatic organisms.


Subject(s)
Androgen Receptor Antagonists/toxicity , Progestins/toxicity , Transcriptome/drug effects , Water Pollutants, Chemical/toxicity , Androgen Antagonists/toxicity , Animal Fins/drug effects , Animal Fins/growth & development , Animals , Cyprinodontiformes/genetics , Cyprinodontiformes/metabolism , Cyprinodontiformes/physiology , Female , Fish Proteins/genetics , Fish Proteins/metabolism , Gas Chromatography-Mass Spectrometry , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , In Situ Hybridization , Levonorgestrel/analysis , Levonorgestrel/isolation & purification , Male , Microarray Analysis , Mifepristone/analysis , Mifepristone/isolation & purification , Solid Phase Extraction , Water Pollutants, Chemical/chemistry
2.
Environ Monit Assess ; 187(10): 619, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26353967

ABSTRACT

Pharmaceuticals are emerging contaminants and it must be noted that approximately 70 % of them are excreted via urine. Therefore, urine usage implies the risk of transfer of pharmaceutical residues to agricultural fields and environment contamination. Thus, this study aimed on the development and validation of a LC-MS/MS method for D-norgestrel (D-NOR) and progesterone (PRO) determination in human urine, as well as the evaluation of the removal efficiency of two methods (storage and evaporation), and the effects of acidification with sulfuric acid. The storage process was evaluated for 6 weeks, while the evaporation was assessed at three different temperatures (50, 75, and 100 °C). All experiments were done with normal urine (pH = 6.0) and acidified urine (pH = 2.0, with sulfuric acid). The results of validation showed good method efficiency. In the second week of storage, higher hormone degradation was observed. In the evaporation method, both D-NOR and PRO were almost completely degraded when the volume was reduced to the lowermost level. Results also indicate that acidification did not affect degradation. Overall, the results showed that combination of two methods can be employed for more efficient hormone removal in urine.


Subject(s)
Environmental Monitoring/methods , Levonorgestrel/isolation & purification , Progesterone/isolation & purification , Urine/chemistry , Adult , Chromatography, Liquid , Healthy Volunteers , Humans , Levonorgestrel/urine , Limit of Detection , Male , Progesterone/urine , Reproducibility of Results , Specimen Handling , Tandem Mass Spectrometry/methods , Temperature , Volatilization , Young Adult
3.
Anal Chim Acta ; 665(2): 176-84, 2010 Apr 30.
Article in English | MEDLINE | ID: mdl-20417328

ABSTRACT

A polyclonal antibody (Ab) for the progestin levonorgestrel (LNG) was generated, and immunochemical assays for its detection, clean-up and concentration were developed. A highly specific microplate diagnostic assay for the detection of LNG was developed that used the enzyme linked immunosorbent assay (ELISA) method. The LNG ELISA developed was sensitive and reproducible; it exhibited I(50) and I(20) values of 3.3+/-1.8 ng mL(-1) and 0.6+/-0.4 ng mL(-1), respectively, and the Abs did not cross react with any of the tested steroid hormones. The above Abs were used to develop a sol-gel-based immunoaffinity purification (IAP) method for concentration and clean-up of LNG that is compatible with subsequent immunochemical or instrumental chemical analytical procedures, such as liquid chromatography followed by mass spectrometry (LC-MS/MS). Development of the columns included successful entrapment of Abs within a tetramethoxysilane (TMOS)-based SiO(2) polymer network. The Abs could bind the free analyte from solution, and the bound analyte could be easily eluted from the sol-gel matrix at high recoveries. The Ab selectivity towards the antigen was high, in both ELISA and the sol-gel columns, but the entrapped Abs cross-reacted with two other steroid hormones--ethynylestradiol (EE2) and nortestosterone (NT) - which share similar epitopes with LNG, despite the lack of cross reactivity in the ELISA. The validity of the method was investigated by LC-MS/MS and a good analytical correlation was obtained.


Subject(s)
Contraceptives, Oral, Synthetic/analysis , Enzyme-Linked Immunosorbent Assay/methods , Levonorgestrel/analysis , Antibodies/immunology , Chromatography, Affinity , Chromatography, High Pressure Liquid , Contraceptives, Oral, Synthetic/isolation & purification , Cross Reactions , Levonorgestrel/isolation & purification , Silanes/chemistry , Silicon Dioxide/chemistry , Solid Phase Extraction , Spectrometry, Mass, Electrospray Ionization
4.
Talanta ; 80(1): 98-103, 2009 Nov 15.
Article in English | MEDLINE | ID: mdl-19782197

ABSTRACT

The preparation and characterization of an immunoaffinity chromatography (IAC) column for the specific extraction and enrichment of trace contraceptive drug levonorgestrel (LNG) from water samples were described. The IAC column was constructed by covalently coupling specific polyclonal antibody against LNG to CNBr-activated Sepharose 4B and packed into a common solid phase extraction (SPE) cartridge. The extraction conditions including loading, washing and eluting solutions, as well as the effect of flow rate on the extraction were carefully optimized. Pure water, 5% of methanol and 50% of methanol were respectively selected as loading, washing and eluting solutions, while the flow rates in the loading, washing and eluting steps were selected to be 1.0, 2.0 and 0.5 mL min(-1), respectively. Under optimal conditions, the IAC column was characterized in terms of maximum capacity, extraction recovery and stability. It was found that, for IAC column packed with 0.2g of solid support immobilized with antibody, the maximum capacity for LNG was about 260 ng. The extraction recoveries of the column for LNG at three different spiked concentrations were within 95.3-106.9%. After more than 35 times repeated usage, there was not significant loss of specific recognition. Using high performance liquid chromatography (HPLC) as an analytical tool, trace amount of LNG in the range of ng L(-1) was found in river water and wastewater samples after 600-fold enrichment, demonstrated the feasibility of the prepared IAC column for LNG extraction.


Subject(s)
Chromatography, Affinity/instrumentation , Contraceptives, Oral, Synthetic/isolation & purification , Levonorgestrel/isolation & purification , Water Pollutants, Chemical/isolation & purification , Chromatography, Affinity/methods , Chromatography, High Pressure Liquid/instrumentation , Chromatography, High Pressure Liquid/methods , Contraceptives, Oral, Synthetic/analysis , Contraceptives, Oral, Synthetic/chemistry , Feasibility Studies , Immunologic Techniques , Levonorgestrel/analysis , Levonorgestrel/chemistry , Molecular Structure , Solid Phase Extraction/instrumentation , Solid Phase Extraction/methods , Water Pollutants, Chemical/analysis
5.
Water Res ; 43(18): 4707-17, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19695660

ABSTRACT

This study investigates the oxidation of pharmaceuticals, endocrine disrupting compounds and pesticides during ozonation applied in drinking water treatment. In the first step, second-order rate constants for the reactions of selected compounds with molecular ozone (k(O3)) were determined in bench-scale experiments at pH 8.10: caffeine (650+/-22M(-1)s(-1)), progesterone (601+/-9M(-1)s(-1)), medroxyprogesterone (558+/-9M(-1)s(-1)), norethindrone (2215+/-76M(-1)s(-1)) and levonorgestrel (1427+/-62M(-1)s(-1)). Compared to phenolic estrogens (estrone, 17beta-estradiol, estriol and 17alpha-ethinylestradiol), the selected progestogen endocrine disruptors reacted far slower with ozone. In the second part of the study, bench-scale experiments were conducted with surface waters spiked with 16 target compounds to assess their oxidative removal using ozone and determine if bench-scale results would accurately predict full-scale removal data. Overall, the data provided evidence that ozone is effective for removing trace organic contaminants from water with ozone doses typically applied in drinking water treatment. Ozonation removed over 80% of caffeine, pharmaceuticals and endocrine disruptors within the CT value of about 2 mg min L(-1). As expected, pesticides were found to be the most recalcitrant compounds to oxidize. Caffeine can be used as an indicator compound to gauge the efficacy of ozone treatment.


Subject(s)
Endocrine Disruptors/chemistry , Ozone/chemistry , Pesticides/chemistry , Pharmaceutical Preparations/chemistry , Water Purification/methods , Water Supply/analysis , Caffeine/chemistry , Caffeine/isolation & purification , Endocrine Disruptors/isolation & purification , Estradiol/chemistry , Estradiol/isolation & purification , Estriol/chemistry , Estriol/isolation & purification , Estrogens/chemistry , Estrogens/isolation & purification , Estrone/chemistry , Estrone/isolation & purification , Hydrogen-Ion Concentration , Levonorgestrel/chemistry , Levonorgestrel/isolation & purification , Medroxyprogesterone/chemistry , Medroxyprogesterone/isolation & purification , Molecular Structure , Norethindrone/chemistry , Norethindrone/isolation & purification , Oxidation-Reduction , Pesticides/isolation & purification , Pharmaceutical Preparations/isolation & purification , Progesterone/chemistry , Progesterone/isolation & purification , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Supply/standards
6.
J Chromatogr A ; 1119(1-2): 51-7, 2006 Jun 30.
Article in English | MEDLINE | ID: mdl-16487534

ABSTRACT

We investigated a thermo-sensitive polymer, poly(N-isopropylacrylamide) (PNIPAAm), which is the basis of an HPLC stationary phase. We prepared a PNIPAAm terminally-modified surface. In this study, we investigated the effect of PNIPAAm on the surface of a stationary phase on separation based on changes of the retention time with the temperature step gradient. As the temperature changed the surface property of the stationary phase switched from hydrophilic to hydrophobic. The retention on the polymer-modified stationary phase remarkably changed upon changing the temperature. Using a column packed with PNIPAAm-modified silica, the separation of steroids was carried out by changing the temperature. With increasing temperature, an increased interaction between solutes and PNIPAAm-grafted surfaces of the stationary phases was observed. A temperature-dependent resolution of steroids was achieved using only water as a mobile phase. The PNIPAAm-modified surface of the stationary phase exhibited temperature-controlled hydrophilic-hydrophobic changes. The drastic and reversible surface hydrophilic-hydrophobic property alteration for PNIPAAm terminally-grafted surfaces should be due to rapid changes in the polymer hydration state around the polymer's transition temperature. A solvent gradient elution-like effect could be achieved with a single mobile phase by programmed temperature changes during chromatographic runs. This system should be highly useful to control the function and property of the stationary phase for HPLC only by changing the temperature with an aqueous solvent.


Subject(s)
Acrylic Resins/chemistry , Chromatography, High Pressure Liquid/methods , Contraceptives, Oral, Combined/urine , Dexamethasone/isolation & purification , Ethinyl Estradiol/isolation & purification , Humans , Hydrocortisone/analogs & derivatives , Hydrocortisone/isolation & purification , Levonorgestrel/isolation & purification , Molecular Conformation , Prednisolone/isolation & purification , Steroids/isolation & purification , Surface Properties , Temperature , Testosterone/isolation & purification
7.
J Pediatr Adolesc Gynecol ; 13(4): 163-6, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11173017

ABSTRACT

A modified mammography technique for localization of concealed Norplant implants and Norplant fragments was applied to four patients, ages 18, 35, 22, and 25. A dedicated mammography unit and mammography film screen system affording high resolution and high contrast was applied under the same conditions to each patient. 26 kilovoltage peak (KVp) was used, ranging from 60 to 150 milliamperes. Using both the automatic exposure control and manual techniques, specific milliampere range depended on the specific case. The technique proved successful, as concealed Norplant capsules were exquisitely visualized by films obtained with a Siemens Mammomat 3000. Applying the same modified technique, precise location of the Norplant implants was determined using a fenestrated compression plate with an alphanumeric grid in a manner similar to hookwire localization of breast lesions under mammographic guidance. The capsules were then safely retrieved. We conclude that this modified technique may provide practitioners with valuable assistance in the exact localization of the Norplant capsule(s) or fragments, thereby facilitating their removal. Application of a modified mammography technique reveals precise localization of concealed Norplant capsules facilitating their removal.


Subject(s)
Contraceptive Agents, Female/isolation & purification , Foreign-Body Migration/diagnostic imaging , Levonorgestrel/isolation & purification , Mammography/methods , Adolescent , Adult , Capsules , Drug Implants , Female , Humans , Mammography/instrumentation
8.
Se Pu ; 17(2): 187-9, 1999 Mar.
Article in Chinese | MEDLINE | ID: mdl-12549165

ABSTRACT

Separation of levonorgestrel, progesterone and testosterone was achieved by using micellar electrokinetic capillary chromatography (MECC). A column of 53 cm (to the detector) x 50 microns i.d. uncoated fused-silica capillary (totally 68 cm in length) and an ultra-violet detector with fixed wavelength at 254 nm were used throughout all the experiments. MECC analysis was optimized by evaluating three different micelle-forming agents, the concentration of SDS and several of organic additives in a 10 mmol/L borate running buffer (pH 9.2). Complete separations were obtained with either 10%-20% acetonitrile or 20 mmol/L 2,6-dimethyl-beta-cyclodextrin (DM-beta-CD) as the modifier in buffer. When the acetonitrile volume fraction was in the range of 0-15%, the migration times of the three steroids increased with the acetonitrile volume fraction, but in the range of 15%-20% acetonitrile concentrations, the situation was opposite. This behavior of the steroids was attributed to the interaction of two opposite effects, an increased mobility due to decreased partition coefficient and a decreased electroosmotic flow (EOF). Both beta-cyclodextrin (beta-CD) and gamma-cyclodextrin (gamma-CD) were found to be inadequate for a satisfactory separation.


Subject(s)
Chromatography, Micellar Electrokinetic Capillary , Levonorgestrel/isolation & purification , Progesterone/isolation & purification , Testosterone/isolation & purification , beta-Cyclodextrins , gamma-Cyclodextrins , Cyclodextrins
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