Etoposide is one of the most successful chemotherapeutic agents used for the treatment of human cancers. The drug kills cells by inhibiting the ability of topoisomerase II to ligate nucleic acids that it cleaves during the double-stranded DNA passage reaction. Etoposide is composed of a polycyclic ring system (rings A-D), a glycosidic moiety at the C4 position, and a pendant ring (E-ring) at the C1 position. Although drug-enzyme contacts, as opposed to drug-DNA interactions, mediate the entry of etoposide into the topoisomerase II-drug-DNA complex, the substituents on etoposide that interact with the enzyme have not been identified. Therefore, saturation transfer difference [ 1 H]-nuclear magnetic resonance spectroscopy and protein-drug competition binding assays were employed to define the groups on etoposide that associate with yeast topoisomerase II and human topoisomerase IIα. Results indicate that the geminal protons of the A-ring, the H5 and H8 protons of the B-ring, as well as the H2' and H6' protons and the 3'-and 5'-methoxyl protons of the pendent E-ring interact with both enzymes in the binary protein-ligand complexes. In contrast, no significant nuclear Overhauser enhancement signals arising from the C-ring, the D-ring, or the C4 glycosidic moiety were observed with either enzyme, suggesting that there is limited or no contact between these portions of etoposide and topoisomerase II in the binary complex. The functional importance of E-ring substituents was confirmed by topoisomerase II-mediated DNA cleavage assays.Etoposide is one of the most successful chemotherapeutic agents used for the treatment of human cancers (1-4). The drug currently is in its third decade of clinical use and is front line

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Continuing our previous studies analyzing drugs of abuse in municipal wastewater, a method was developed for the analysis of opiates in wastewater samples using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). Eight opiate drugs and metabolites were analyzed including codeine, hydrocodone, hydromorphone, 6-monoacetylmorphine (6-MAM, the primary urinary metabolite of heroin), morphine, norhydrocodone (the primary urinary metabolite of hydrocodone), oxycodone and oxymorphone. These drugs were chosen because of their widespread abuse. Wastewater samples were collected at both the Oxford Waste Water Treatment Plant in Oxford, Mississippi (MS) and the University Wastewater Treatment Plant in University, MS. These wastewater samples were collected on weekends in which the Ole Miss Rebel football team held home games (Vaught-Hemingway Stadium, University, MS 38677). The collected samples were analyzed using a validated method and found to contain codeine, hydrocodone, hydromorphone, morphine, norhydrocodone, oxycodone and oxymorphone. None of the samples contained 6-MAM.

Background: Phytocannabinoids naturally occur in the cannabis plant ( Cannabis sativa ), and Δ 9 -tetrahydrocannabinol (THC) and cannabidiol (CBD) predominate. There is a need for rapid inexpensive methods to quantify total THC (for statutory definition) and THC–CBD ratio (for classification into three chemotypes). This study explores the capabilities of a spectroscopic technique that combines ultraviolet-visible and fluorescence, absorbance-transmittance excitation emission matrix (A-TEEM). Methods: The A-TEEM technique classifies 49 dry flower extracts into three C. sativa chemotypes, and quantifies the total THC–CBD ratio, using validated gas chromatography (GC)-flame ionization (FID) and High-Performance Liquid Chromatography (HPLC) methods for reference. Multivariate methods used are principal components analysis for a chemotype classification, extreme gradient boost (XGB) discriminant analysis (DA) to classify unknown samples by chemotype, and XGB regression to quantify total THC and CBD content using GC-FID and HPLC data on the same samples. Results: The A-TEEM technique provides robust classification of C. sativa samples, predicting chemotype classification, defined by THC–CBD content, of unknown samples with 100% accuracy. In addition, A-TEEM can quantify total THC and CBD levels relevant to statutory determination, with limit of quantifications (LOQs) of 0.061% (THC) and 0.059% (CBD), and high cross-validation (>0.99) and prediction (>0.99), using a GC-FID method for reference data; and LOQs of 0.026% (THC) and 0.080% (CBD) with high cross-validation (>0.98) and prediction (>0.98), using an HPLC method for reference data. A-TEEM is highly predictive in separately quantifying acid and neutral forms of THC and CBD with HPLC reference data. Conclusions: The A-TEEM technique provides a sensitive method for the qualitative and quantitative characterization of the major cannabinoids in solution, with LOQs comparable with GC-FID and HPLC, and high values of cross-validation and prediction. As a spectroscopic technique, it is rapid, with data acquisition <45 sec per measurement; sample preparation is simple, requiring only solvent extraction. A-TEEM has the sensitivity to resolve and quantify cannabinoids in solution based on their unique spectral characteristics. Discrimination of legal and illegal chemotypes can be rapidly verified using XGB DA, and quantitation of statutory levels of total THC and total CBD comparable with GC-FID and HPLC can be obtained using XBD regression.

From the structure of DNA, [1] to computer science, [2] and space-station batteries, [3] several key scientific discoveries that enhance our lives today,w ere made by marginalized scientists.T hese three scientists,R osalind E. Franklin, Alan M. Turing and Olga D. Gonzµlez-Sanabria, did not conform to the cultural expectations of how scientists should look and behave.U nfortunately,m arginalized scientists are often viewed as just aresource rather than the lifeblood that constitutes science itself.W eneed to embrace scientists from all walks of life and corners of the globe;t his will also mean that nobody is excluded from tackling the life-threatening societal challenges that lie ahead. An awareness of science policy is essential to safeguarding our future.

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A method was developed for the analysis of stimulant drugs, opiates, synthetic opiates, PCP, and benzodiazepines in wastewater samples using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). A total of 33 compounds (stimulant-type drugs and metabolites of opiates, synthetic opiates, PCP, and benzodiazepines) were analyzed. These drugs included amphetamine (Amp) (1), methamphetamine (Meth) (2), methylenedioxyamphetamine (MDA) (3), methylenedioxymethamphetamine (MDMA) (4), methylenedioxyethylamphetamine (MDEA) (5), benzoylecgonine (BE, the major metabolite of Coc) (6), cocaine (Coc) (7), 6-monoacetylmorphine (6-MAM, the primary urinary metabolite of heroin) (8), codeine (9), hydrocodone (10), hydromorphone (11), morphine (12), norhydrocodone (the primary urinary metabolite of hydrocodone) (13), oxycodone (14), oxymorphone (15), 2-ethylidine-1,5-dimethyl-3,3-diphenylpyrolidine (EDDP, the primary urinary metabolite of methadone) (16), fentanyl (17), meperidine (18), methadone (19), norfentanyl (the primary urinary metabolite of fentanyl) (20), normeperidine (the primary urinary metabolite of meperidine) (21), phencyclidine (PCP) (22), tramadol (23), alprazolam (24), temazepam (25), nordiazepam (26), chlordiazepoxide (27), flurazepam (28), oxazepam (29), α-OH-alprazolam (the primary urinary metabolite of alprazolam) (30), α-OH-triazolam (the primary urinary metabolite of triazolam) (31), 2-OH-ethylflurazepam (the primary urinary metabolite of flurazepam) (32), and 7-NH-flunitrazepam (the primary urinary metabolite of flunitrazepam) (33). These drugs were chosen because of their widespread abuse. Wastewater samples were collected at both the Oxford Wastewater Treatment Plant in Oxford, Mississippi (MS), and the University Wastewater Treatment Plant in University, MS. Samples were collected on weekends on which the Ole Miss Rebel football team held home games (Vaught-Hemingway Stadium, University, MS 38677). The collected samples were analyzed using a validated method and found to contain Amp, Meth, MDMA, MDA, Coc, BE, codeine, hydrocodone, hydromorphone, morphine, norhydrocodone, oxycodone, oxymorphone, tramadol, EDDP, meperidine, normeperidine, methadone, alprazolam, α-OH-alprazolam, nordiazepam, oxazepam, and temazepam. None of the samples contained MDEA, 6-MAM, fentanyl, norfentanyl, PCP, chlordiazepoxide, flurazepam, 2-OH-ethylflurazepam, 7-NH-flunitrazepam, and α-OH-triazolam.

Continuing our studies for the analyses of drugs of abuse in municipal wastewater, a method was developed for the analysis of benzodiazepines in wastewater samples using liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS). Ten benzodiazepines and metabolites were analyzed (structures were found), including alprazolam, α-OH-alprazolam (the primary urinary metabolite of alprazolam), chlordiazepoxide, flurazepam, 2-OH-ethylflurazepam (the primary urinary metabolite of flurazepam), 7-NH2-flunitrazepam, nordiazepam, oxazepam, temazepam and α-OH-triazolam (the primary urinary metabolite of triazolam) (representative chromatograms were found). These drugs were chosen because of their widespread abuse. Wastewater samples were collected at both the Oxford Wastewater Treatment Plant (WWTP) in Oxford, Mississippi (MS) and the University WWTP in University, MS. These wastewater samples were collected on weekends in which the Ole Miss Rebel football team held home games at the Vaught-Hemingway Stadium, University, and one weekend on which there was no game. The collected samples were analyzed using a validated method and found to contain alprazolam, α-OH-alprazolam, nordiazepam, oxazepam and temazepam. None of the samples contained chlordiazepoxide, flurazepam, 2-hydroxyethyl-flurazepam, 7-NH2-flunitrazepam and α-OH-triazolam.