The purpose of this study was to explore the stability and toxicity of the herbicides and their d... more The purpose of this study was to explore the stability and toxicity of the herbicides and their degradation byproduct after exposure to different environmental factors. Triazines (atrazine, propazine, simazine) and chloroacetanilides (acetochlor, alachlor, metolachlor) which are commonly used herbicides were evaluated for cytotoxicity in different UV (254 nm and 365 nm) and temperature (4 C, 23 C, and 40 C) conditions as well as degradation rates. Atrazine with the highest LD 50 (4.23 μg mL À1) was less toxic than the other tested triazine herbicides Chloroacetanilides tested were more toxic than tested triazines, with LD 50 0.08-1.42 μg mL À1 vs 1.44-4.23 μg mL À1 , respectively. Alachlor with LD 50 0.08 μg mL À1 showed the strongest toxic response as compared with other tested herbicides. Temperatures only did not alter cytotoxicity of the tested herbicides, except for acetochlor and alachlor showing about 45 % more cell death after exposure to 40 C for 2 h. At all 3 tested temperatures, 2 h of UV treatments did not affect cytotoxic effects of the tested herbicides, except for acetochlor and alachlor. At 4 C, acetochlor toxicity was attenuated about 63 % after UV 365 nm exposure; but alachlor toxicity was enhanced after either UV 254 or 365 nm exposure for about 40 % and 24 %, respectively. At 23 C, acetochlor toxicity was enhanced about 35 % after UV 254 nm exposure, but attenuated about 48 % after UV 365 nm exposure. Alachlor toxicity was enhanced about 34 % after UV 254 nm and 23 C exposure. In combination of UV 254 nm and 40 C, acetochlor toxicity was lowered by 63 % and alachlor toxicity was no change as compared with 4 C, no UV group. After co-treatment with UV 365 nm and 40 C both acetochlor and alachlor toxicity was enhanced 55 % and 80 %, respectively. Through degradation analysis by LC-MS/MS, alachlor showed the most dramatic degradation (only 0.58 %-10.58 % remaining) after heat and UV treatments.
This study aimed to examine the effect of body image and self-esteem on selfie addiction among fr... more This study aimed to examine the effect of body image and self-esteem on selfie addiction among fresh female students at Ahfad University(Sudan), as well as to investigate the correlation between body image and self-esteem. To achieve those objectives, the researcher adopted the descriptive research method. The sample included (400) female students whose average age was (22.5) years, selected by using a simple random sample. The study was conducted by administering three scales. The results of the study indicated that (50%) of the sample suffered from the selfie addiction between moderate to severe levels. There was a significant correlation between selfie addiction, self-esteem and body image. Moreover, it was found that both body image and self-esteem had a predictive ability to increase likelihood of selfie addiction among females. The study recommended that professionals should consider preparing prevention programs for those who have traits of a selfie addiction behavior.
Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C... more Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C10 - are DNA alkylating agents. Their cytotoxicity is attributed to their ability to generate DNA monoadducts as well as intrastrand and interstrand cross-links (ICLs). The major monoadducts generated by MC and DMC in tumor cells have opposite stereochemistry at carbon one of the guanine-mitosene bond: trans (or alpha) for MC and cis (or beta) for DMC. We hypothesize that local disruptions of DNA structure from trans or cis adducts are responsible for the different biochemical responses produced by MC and DMC. Access to DNA substrates bearing cis and trans MC/DMC lesions is essential to verify this hypothesis. Synthetic oligonucleotides bearing trans lesions can be obtained by bio-mimetic methods. However, this approach does not yield cis adducts. This report presents the first chemical synthesis of a cis mitosene DNA adduct. We also examined the stereopreference exhibited by the two drugs at the mononucleotide level by analyzing the formation of cis and trans adducts in the reaction of deoxyguanosine with MC or DMC using a variety of activation conditions. In addition, we performed Density Functional Theory calculations to evaluate the energies of these reactions. Direct alkylation under autocatalytic or bifunctional conditions yielded preferentially alpha adducts with both MC and DMC. DFT calculations showed that under bifunctional activation, the thermodynamically favored adducts are alpha, trans, for MC and beta, cis, for DMC. This suggests that the duplex DNA structure may stabilize/oriente the activated pro-drugs so that, with DMC, formation of the thermodynamically favored beta products are possible in a cellular environment.
According to current surveys and overdoses data, there is a drug crisis in the USA. Wastewater-ba... more According to current surveys and overdoses data, there is a drug crisis in the USA. Wastewater-based epidemiology (WBE) is an evolving discipline that analyses wastewater samples to detect drugs and metabolites to estimate drug consumption in a certain community. This study demonstrates how drug relative presence could be tracked by testing wastewater, providing real-time results, in different boroughs in New York City throughout 1 year. We developed and fully validated two analytical methods, one for 21 drugs and metabolites, including nicotine, cocaine, amphetamines, opioids and cannabis markers; and another for the normalization factor creatinine. Both methods were performed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using positive electrospray ionization, achieving a limit of quantification of 5-10 ng/L for drugs and metabolites, and 0.01 mg/L for creatinine. These methods were applied to 48 one-time grab wastewater samples collected from six wastewater treatment plants in New York City (Manhattan, The Bronx, Queens and Brooklyn), eight different times throughout 2016, before and after major holidays, including Memorial Day, 4th of July, Labour Day and New Year's. In this study, the drug group normalized concentrations present in the wastewater samples, in decreasing order, were cocaine, nicotine, opioids, cannabis and amphetamines. When looking at individual compounds, the one with the highest normalized concentration was benzoylecgonine (BE), followed by cotinine, morphine and 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH). To estimate community use, these concentrations were multiplied by the corresponding correction factor, and the most present were THCCOOH, followed by BE, cotinine and morphine. When comparing the treatment plants by drug group (nicotine, cocaine, amphetamines, opioids and cannabis), samples collected from The Bronx had the highest normalized concentrations for nicotine, cocaine and opioids; The Bronx and Manhattan for cannabis; and Manhattan and Queens for amphetamines. In most of the cases, no effect due to holiday was observed. This study provides the first snapshot of drug use in New York City and how that changes between key calendar dates employing wastewater analysis.
Pokeweed antiviral protein (PAP) is a ribosome inactivating protein (RIP) that depurinates the sa... more Pokeweed antiviral protein (PAP) is a ribosome inactivating protein (RIP) that depurinates the sarcin/ricin loop (SRL) of rRNA, inhibiting protein synthesis. PAP depurinates viral RNA, and in doing so, lowers the infectivity of many plant viruses. The mechanism by which PAP accesses uncapped viral RNA is not known, impeding scientists from developing effective antiviral agents for the prevention of the diseases caused by uncapped RNA viruses. Kinetic rates of PAP interacting with tobacco etch virus (TEV) RNA, in the presence and absence of eIFiso4F, were examined, addressing how the eIF affects selective PAP targeting and depurination of the uncapped viral RNA. PAP-eIFs copurification assay and fluorescence resonance energy transfer demonstrate that PAP forms a ternary complex with the eIFiso4G and eIFiso4E, directing the depurination of uncapped viral RNA. eIFiso4F selectively targets PAP to depurinate TEV RNA by increasing PAP's specificity constant for uncapped viral RNA 12-fold, when compared to the depurination of an oligonucleotide RNA that mimics the SRL of large rRNA, and cellular capped luciferase mRNA. This explains how PAP is able to lower infectivity of pokeweed viruses, while preserving its own ribosomes and cellular RNA from depurination: PAP utilizes cellular eIFiso4F in a novel strategy to target uncapped viral RNA. It may be possible to modulate and utilize these PAP-eIFs interactions for their public health benefit; by repurposing them to selectively target PAP to depurinate uncapped viral RNA, many plant and animal diseases caused by these viruses could be alleviated.
Mitomycin C (MC) is a well-known DNA alkylating agent. MC analog, 10-decarbamoyl mitomycin C (DMC... more Mitomycin C (MC) is a well-known DNA alkylating agent. MC analog, 10-decarbamoyl mitomycin C (DMC), unlike MC, has stronger effects on cancer with p53 mutation. We previously demonstrated that MC/DMC could activate p21 in MCF-7 (p53-proficient) and K562 (p53-deficient) cells in a p53-independent mode. This study aimed to elucidate the upstream signaling pathway of p21 activation triggered by MC/DMC. Besides p53, Akt plays an important role on deactivating p21 . The results showed that MC/DMC inhibited Akt in MCF-7 cells, but not in K562 cells. By knocking down p53, the Akt inhibition in MCF-7 cells was alleviated. This implied that the deactivated Akt caused by MC/DMC was p53-dependent. With Akt activator (SC79), p21 activation triggered by MC/DMC in MCF-7 cells was not reduced. This indicated that Akt inhibition triggered by MC/DMC was not associated with MC/DMC-induced p21 activation. Label-free quantitative proteomic profiling analysis revealed that DMC has a stronger effect on d...
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 5, 2018
Mitomycin C (MC), a potent antitumor drug, and decarbamoylmitomycin C (DMC), a derivative lacking... more Mitomycin C (MC), a potent antitumor drug, and decarbamoylmitomycin C (DMC), a derivative lacking the carbamoyl group, form highly cytotoxic DNA interstrand crosslinks. The major interstrand crosslink formed by DMC is the C1'' epimer of the major crosslink formed by MC. The molecular basis for the stereochemical configuration exhibited by DMC was investigated using biomimetic synthesis. The formation of DNA-DNA crosslinks by DMC is diastereospecific and diastereodivergent: Only the 1''S-diastereomer of the initially formed monoadduct can form crosslinks at GpC sequences, and only the 1''R-diastereomer of the monoadduct can form crosslinks at CpG sequences. We also show that CpG and GpC sequences react with divergent diastereoselectivity in the first alkylation step: 1"S stereochemistry is favored at GpC sequences and 1''R stereochemistry is favored at CpG sequences. Therefore, the first alkylation step results, at each sequence, in the selective ...
A 2-protected cis-amino mitosene undergoes an irreversible acetone promoted isomerization and con... more A 2-protected cis-amino mitosene undergoes an irreversible acetone promoted isomerization and converts to the 1-isomer. Kinetic studies and DFT calculations of the reaction are reported. An organocatalytic mechanism is proposed, involving a covalent intermediate formed by reaction of the mitosene and acetone.
Background: Cathinones better known as bath salts have been listed as illicit drugs since 2011. F... more Background: Cathinones better known as bath salts have been listed as illicit drugs since 2011. Few studies have focused on the analytical extraction techniques and the matrix effect affecting their detection and quantification in biological samples. Matrix suppression of the signal of cathinones has been previously observed in urine sample by LC-MS/MS. This study is aimed to use the standard addition method to overcome the plasma matrix effect on the quantification of cathinone and mephedrone by LC-MS/MS. Findings: The results showed the matrix effect for cathinone at lowest tested concentration (10 ng/ml) was significantly reduced from 210.9 to 133.7%, but not for mephedrone (from 196.8 to 191.9%) by using standard addition method. At the higher tested concentrations of samples, the matrix effects were significantly reduced for both cathinone and mephedrone by using standard addition technique. Conclusions: Standard addition quantitative technique can serve as an alternative quantitative method for LC-MS/MS when suitable internal standards are not available.
Existing drug discovery process follows a reductionist model of ″one-drug-one-gene-one-disease,″ ... more Existing drug discovery process follows a reductionist model of ″one-drug-one-gene-one-disease,″ which is not adequate to tackle complex diseases that involve multiple malfunctioned genes. The availability of big omics data offers new opportunities to transform the drug discovery process into a new paradigm of systems pharmacology that focuses on designing drugs to target molecular interaction networks instead of a single gene. Here, we develop a reliable multi-rank, multi-layered recommender system ANTENNA to mine large-scale chemical genomics and disease association data for the prediction of novel drug-gene-disease associations. ANTENNA integrates a novel tri-factorization based dual-regularized weighted and imputed One Class Collaborative Filtering (OCCF) algorithm tREMAP with a statistical framework that is based on Random Walk with Restart and can assess the reliability of a specific prediction. In the benchmark study, tREMAP clearly outperforms the single rank OCCF. We apply ...
Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion... more Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion products in wastewater to obtain information about exposure to drugs in defined population groups. We developed and validated an analytical method for the simultaneous determination of opioids (morphine, oxycodone, hydrocodone, oxymorphone and hydromorphone), and cannabinoids (D 9-tetrahydrocannabinol, 11-nor-9-carboxytetrahydrocannabinol (THCCOOH) and THCCOOH-glucuronide) in raw-influent wastewater samples by ultra-high performance liquid chromatography-tandem mass spectrometry. Method validation included linearity (5-1 000 ng/L for opioids, 10-1 000 ng/L for cannabinoids), imprecision (<21.2%), accuracy (83%-131%), matrix effect (from-35.1% to-14.7%) and extraction efficiency (25%-84%), limit of detection (1-5 ng/L) and quantification (5-10 ng/L) and auto-sampler stability (no loss detected). River and wastewater samples were collected in triplicate from different locations in New York City and stored at ¡20 C until analysis. Water from sewage overflow location tested positive for morphine (10.7 ng/L), oxycodone (4.2-23.5 ng/L), oxymorphone (4.8 ng/L) and hydromorphone (4.2 ng/L). Raw influent wastewater samples tested positive for morphine (133.0-258.3 ng/L), oxycodone (31.1-63.6 ng/L), oxymorphone (16.0-56.8 ng/L), hydromorphone (6.8-18.0 ng/L), hydrocodone (4.0-12.8 ng/L) and THCCOOH (168.2-772.0 ng/L). This method is sensitive and specific for opioids and marijuana determination in wastewater samples.
Mitomycin C (MC), a commonly used anticancer drug, induces DNA damage via DNA alkylation. Decarba... more Mitomycin C (MC), a commonly used anticancer drug, induces DNA damage via DNA alkylation. Decarbamoyl mitomycin C (DMC), another mitomycin lacking the carbamate at C10, generates similar lesions as MC. Interstrand cross-links (ICLs) are believed to be the lesions primarily responsible for the cytotoxicity of MC and DMC. The major ICL generated by MC (α-ICL) has a trans stereochemistry at the guanine-drug linkage whereas the major ICL from DMC (β-ICL) has the opposite, cis, stereochemistry. In addition, DMC can provoke strong p53-independent cell death. Our hypothesis is that the stereochemistry of the major unique β-ICL generated by DMC is responsible for this p53-independent cell death signaling. p53 gene is inactively mutated in more than half of human cancers. p21 WAF1/CIP1 known as a major effector of p53 is involved in p53-dependent and-independent control of cell proliferation and death. This study revealed the role of p21 WAF1/CIP1 on MC and DMC triggered cell damage. MCF-7 (p53-proficient) and K562 (p53-deficient) cells were used. Cell cycle distributions were shifted to the G1/S phase in MCF-7 treated with MC and DMC, but were shifted to the S phase in K562. p21 WAF1/CIP1 activation was observed in both cells treated with MC and DMC, and DMC triggered more significant activation. Knocking down p53 in MCF-7 did not attenuate MC and DMC induced p21 WAF1/CIP1 activation. The α-ICL itself was enough to cause p21 WAF1/CIP1 activation.
Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C... more Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C10 - are DNA alkylating agents. Their cytotoxicity is attributed to their ability to generate DNA monoadducts as well as intrastrand and interstrand cross-links (ICLs). The major monoadducts generated by MC and DMC in tumor cells have opposite stereochemistry at carbon one of the guanine-mitosene bond: trans (or alpha) for MC and cis (or beta) for DMC. We hypothesize that local disruptions of DNA structure from trans or cis adducts are responsible for the different biochemical responses produced by MC and DMC. Access to DNA substrates bearing cis and trans MC/DMC lesions is essential to verify this hypothesis. Synthetic oligonucleotides bearing trans lesions can be obtained by bio-mimetic methods. However, this approach does not yield cis adducts. This report presents the first chemical synthesis of a cis mitosene DNA adduct. We also examined the stereopreference exhibited by the two drugs at the mononucleotide level by analyzing the formation of cis and trans adducts in the reaction of deoxyguanosine with MC or DMC using a variety of activation conditions. In addition, we performed Density Functional Theory calculations to evaluate the energies of these reactions. Direct alkylation under autocatalytic or bifunctional conditions yielded preferentially alpha adducts with both MC and DMC. DFT calculations showed that under bifunctional activation, the thermodynamically favored adducts are alpha, trans, for MC and beta, cis, for DMC. This suggests that the duplex DNA structure may stabilize/oriente the activated pro-drugs so that, with DMC, formation of the thermodynamically favored beta products are possible in a cellular environment.
Three cobalt(II) complexes based on 4'-chloro-2,2':6',2''-terpyridine (4'-Cltpy) have been synthe... more Three cobalt(II) complexes based on 4'-chloro-2,2':6',2''-terpyridine (4'-Cltpy) have been synthesized and structurally characterized by X-ray crystallography. The reaction with a 1:1 metal-to-ligand ratio in a mixed CH 2 Cl 2-MeOH solvent afforded the mononuclear complex Co(4'-Cltpy)Cl 2 (1) that mimicks the previously reported Cu(4'-Cltpy)Cl 2 , while altering the metal-to-ligand ratio to 2:1 under the same reaction conditions resulted in the formation of a different complex with a component of [Co(4'-Cltpy)Cl 2 ][Co 2 (4'-Cltpy) 2 Cl 4 ] (2), based on single crystal X-ray structural analysis. The presence of both a mononuclear molecule Co(4'-Cltpy)Cl 2 and dinuclear Cl-bridging Co 2 (4'-Cltpy) 2 Cl 4 in 2 was revealed. The replacement of CoCl 2 with Co(SCN) 2 under the same reaction conditions as for 1 gave a similar mononuclear Co(4'-Cltpy)(SCN) 2 (3). The cobalt(II) complexes along with the known copper analogue 4 were investigated for their in-vitro cytotoxic activity towards two human cancer cell lines, the human breast cancer (MCF-7) and leukemia (K562) cells, and distinct cytotoxicity was observed.
Previous studies point to quaternary assembly of dopamine transporters (DATs) in oligomers. Howev... more Previous studies point to quaternary assembly of dopamine transporters (DATs) in oligomers. However, it is not clear whether the protomers function independently in the oligomer. Is each protomer an entirely separate unit that takes up dopamine and is inhibited by drugs known to block DAT function? In this work, human embryonic kidney 293 cells were co-transfected with DAT constructs possessing differential binding affinities for the phenyltropane cocaine analog, [(3) H]WIN35,428. It was assessed whether the binding properties in co-expressing cells capable of forming hetero-oligomers differ from those in preparations obtained from mixed singly transfected cells where such oligomers cannot occur. A method is described that replaces laborious 'mixing' experiments with an in silico method predicting binding parameters from those observed for the singly expressed constructs. Among five pairs of constructs tested, statistically significant interactions were found between protome...
ABSTRACT A thiourea moiety has been introduced into a salen-type ligand scaffold to give a new un... more ABSTRACT A thiourea moiety has been introduced into a salen-type ligand scaffold to give a new unsymmetric ligand by CLICK chemistry. The cobalt(II) and nickel(II) complexes were prepared by a one-pot procedure and structurally characterized by X-ray crystallography. Both complexes are isomorphic and exhibit a tetra-coordinate metal center in a near square planar N2OS coordination environment. Intermolecular hydrogen bonds mediated by solvated methanol assemble the complexes into one-dimensional helical chains with P- and M-chirality. Cytotoxic activities of both complexes against the PC12 and HEK293 cells were studied.
The purpose of this study was to explore the stability and toxicity of the herbicides and their d... more The purpose of this study was to explore the stability and toxicity of the herbicides and their degradation byproduct after exposure to different environmental factors. Triazines (atrazine, propazine, simazine) and chloroacetanilides (acetochlor, alachlor, metolachlor) which are commonly used herbicides were evaluated for cytotoxicity in different UV (254 nm and 365 nm) and temperature (4 C, 23 C, and 40 C) conditions as well as degradation rates. Atrazine with the highest LD 50 (4.23 μg mL À1) was less toxic than the other tested triazine herbicides Chloroacetanilides tested were more toxic than tested triazines, with LD 50 0.08-1.42 μg mL À1 vs 1.44-4.23 μg mL À1 , respectively. Alachlor with LD 50 0.08 μg mL À1 showed the strongest toxic response as compared with other tested herbicides. Temperatures only did not alter cytotoxicity of the tested herbicides, except for acetochlor and alachlor showing about 45 % more cell death after exposure to 40 C for 2 h. At all 3 tested temperatures, 2 h of UV treatments did not affect cytotoxic effects of the tested herbicides, except for acetochlor and alachlor. At 4 C, acetochlor toxicity was attenuated about 63 % after UV 365 nm exposure; but alachlor toxicity was enhanced after either UV 254 or 365 nm exposure for about 40 % and 24 %, respectively. At 23 C, acetochlor toxicity was enhanced about 35 % after UV 254 nm exposure, but attenuated about 48 % after UV 365 nm exposure. Alachlor toxicity was enhanced about 34 % after UV 254 nm and 23 C exposure. In combination of UV 254 nm and 40 C, acetochlor toxicity was lowered by 63 % and alachlor toxicity was no change as compared with 4 C, no UV group. After co-treatment with UV 365 nm and 40 C both acetochlor and alachlor toxicity was enhanced 55 % and 80 %, respectively. Through degradation analysis by LC-MS/MS, alachlor showed the most dramatic degradation (only 0.58 %-10.58 % remaining) after heat and UV treatments.
This study aimed to examine the effect of body image and self-esteem on selfie addiction among fr... more This study aimed to examine the effect of body image and self-esteem on selfie addiction among fresh female students at Ahfad University(Sudan), as well as to investigate the correlation between body image and self-esteem. To achieve those objectives, the researcher adopted the descriptive research method. The sample included (400) female students whose average age was (22.5) years, selected by using a simple random sample. The study was conducted by administering three scales. The results of the study indicated that (50%) of the sample suffered from the selfie addiction between moderate to severe levels. There was a significant correlation between selfie addiction, self-esteem and body image. Moreover, it was found that both body image and self-esteem had a predictive ability to increase likelihood of selfie addiction among females. The study recommended that professionals should consider preparing prevention programs for those who have traits of a selfie addiction behavior.
Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C... more Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C10 - are DNA alkylating agents. Their cytotoxicity is attributed to their ability to generate DNA monoadducts as well as intrastrand and interstrand cross-links (ICLs). The major monoadducts generated by MC and DMC in tumor cells have opposite stereochemistry at carbon one of the guanine-mitosene bond: trans (or alpha) for MC and cis (or beta) for DMC. We hypothesize that local disruptions of DNA structure from trans or cis adducts are responsible for the different biochemical responses produced by MC and DMC. Access to DNA substrates bearing cis and trans MC/DMC lesions is essential to verify this hypothesis. Synthetic oligonucleotides bearing trans lesions can be obtained by bio-mimetic methods. However, this approach does not yield cis adducts. This report presents the first chemical synthesis of a cis mitosene DNA adduct. We also examined the stereopreference exhibited by the two drugs at the mononucleotide level by analyzing the formation of cis and trans adducts in the reaction of deoxyguanosine with MC or DMC using a variety of activation conditions. In addition, we performed Density Functional Theory calculations to evaluate the energies of these reactions. Direct alkylation under autocatalytic or bifunctional conditions yielded preferentially alpha adducts with both MC and DMC. DFT calculations showed that under bifunctional activation, the thermodynamically favored adducts are alpha, trans, for MC and beta, cis, for DMC. This suggests that the duplex DNA structure may stabilize/oriente the activated pro-drugs so that, with DMC, formation of the thermodynamically favored beta products are possible in a cellular environment.
According to current surveys and overdoses data, there is a drug crisis in the USA. Wastewater-ba... more According to current surveys and overdoses data, there is a drug crisis in the USA. Wastewater-based epidemiology (WBE) is an evolving discipline that analyses wastewater samples to detect drugs and metabolites to estimate drug consumption in a certain community. This study demonstrates how drug relative presence could be tracked by testing wastewater, providing real-time results, in different boroughs in New York City throughout 1 year. We developed and fully validated two analytical methods, one for 21 drugs and metabolites, including nicotine, cocaine, amphetamines, opioids and cannabis markers; and another for the normalization factor creatinine. Both methods were performed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using positive electrospray ionization, achieving a limit of quantification of 5-10 ng/L for drugs and metabolites, and 0.01 mg/L for creatinine. These methods were applied to 48 one-time grab wastewater samples collected from six wastewater treatment plants in New York City (Manhattan, The Bronx, Queens and Brooklyn), eight different times throughout 2016, before and after major holidays, including Memorial Day, 4th of July, Labour Day and New Year's. In this study, the drug group normalized concentrations present in the wastewater samples, in decreasing order, were cocaine, nicotine, opioids, cannabis and amphetamines. When looking at individual compounds, the one with the highest normalized concentration was benzoylecgonine (BE), followed by cotinine, morphine and 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH). To estimate community use, these concentrations were multiplied by the corresponding correction factor, and the most present were THCCOOH, followed by BE, cotinine and morphine. When comparing the treatment plants by drug group (nicotine, cocaine, amphetamines, opioids and cannabis), samples collected from The Bronx had the highest normalized concentrations for nicotine, cocaine and opioids; The Bronx and Manhattan for cannabis; and Manhattan and Queens for amphetamines. In most of the cases, no effect due to holiday was observed. This study provides the first snapshot of drug use in New York City and how that changes between key calendar dates employing wastewater analysis.
Pokeweed antiviral protein (PAP) is a ribosome inactivating protein (RIP) that depurinates the sa... more Pokeweed antiviral protein (PAP) is a ribosome inactivating protein (RIP) that depurinates the sarcin/ricin loop (SRL) of rRNA, inhibiting protein synthesis. PAP depurinates viral RNA, and in doing so, lowers the infectivity of many plant viruses. The mechanism by which PAP accesses uncapped viral RNA is not known, impeding scientists from developing effective antiviral agents for the prevention of the diseases caused by uncapped RNA viruses. Kinetic rates of PAP interacting with tobacco etch virus (TEV) RNA, in the presence and absence of eIFiso4F, were examined, addressing how the eIF affects selective PAP targeting and depurination of the uncapped viral RNA. PAP-eIFs copurification assay and fluorescence resonance energy transfer demonstrate that PAP forms a ternary complex with the eIFiso4G and eIFiso4E, directing the depurination of uncapped viral RNA. eIFiso4F selectively targets PAP to depurinate TEV RNA by increasing PAP's specificity constant for uncapped viral RNA 12-fold, when compared to the depurination of an oligonucleotide RNA that mimics the SRL of large rRNA, and cellular capped luciferase mRNA. This explains how PAP is able to lower infectivity of pokeweed viruses, while preserving its own ribosomes and cellular RNA from depurination: PAP utilizes cellular eIFiso4F in a novel strategy to target uncapped viral RNA. It may be possible to modulate and utilize these PAP-eIFs interactions for their public health benefit; by repurposing them to selectively target PAP to depurinate uncapped viral RNA, many plant and animal diseases caused by these viruses could be alleviated.
Mitomycin C (MC) is a well-known DNA alkylating agent. MC analog, 10-decarbamoyl mitomycin C (DMC... more Mitomycin C (MC) is a well-known DNA alkylating agent. MC analog, 10-decarbamoyl mitomycin C (DMC), unlike MC, has stronger effects on cancer with p53 mutation. We previously demonstrated that MC/DMC could activate p21 in MCF-7 (p53-proficient) and K562 (p53-deficient) cells in a p53-independent mode. This study aimed to elucidate the upstream signaling pathway of p21 activation triggered by MC/DMC. Besides p53, Akt plays an important role on deactivating p21 . The results showed that MC/DMC inhibited Akt in MCF-7 cells, but not in K562 cells. By knocking down p53, the Akt inhibition in MCF-7 cells was alleviated. This implied that the deactivated Akt caused by MC/DMC was p53-dependent. With Akt activator (SC79), p21 activation triggered by MC/DMC in MCF-7 cells was not reduced. This indicated that Akt inhibition triggered by MC/DMC was not associated with MC/DMC-induced p21 activation. Label-free quantitative proteomic profiling analysis revealed that DMC has a stronger effect on d...
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 5, 2018
Mitomycin C (MC), a potent antitumor drug, and decarbamoylmitomycin C (DMC), a derivative lacking... more Mitomycin C (MC), a potent antitumor drug, and decarbamoylmitomycin C (DMC), a derivative lacking the carbamoyl group, form highly cytotoxic DNA interstrand crosslinks. The major interstrand crosslink formed by DMC is the C1'' epimer of the major crosslink formed by MC. The molecular basis for the stereochemical configuration exhibited by DMC was investigated using biomimetic synthesis. The formation of DNA-DNA crosslinks by DMC is diastereospecific and diastereodivergent: Only the 1''S-diastereomer of the initially formed monoadduct can form crosslinks at GpC sequences, and only the 1''R-diastereomer of the monoadduct can form crosslinks at CpG sequences. We also show that CpG and GpC sequences react with divergent diastereoselectivity in the first alkylation step: 1"S stereochemistry is favored at GpC sequences and 1''R stereochemistry is favored at CpG sequences. Therefore, the first alkylation step results, at each sequence, in the selective ...
A 2-protected cis-amino mitosene undergoes an irreversible acetone promoted isomerization and con... more A 2-protected cis-amino mitosene undergoes an irreversible acetone promoted isomerization and converts to the 1-isomer. Kinetic studies and DFT calculations of the reaction are reported. An organocatalytic mechanism is proposed, involving a covalent intermediate formed by reaction of the mitosene and acetone.
Background: Cathinones better known as bath salts have been listed as illicit drugs since 2011. F... more Background: Cathinones better known as bath salts have been listed as illicit drugs since 2011. Few studies have focused on the analytical extraction techniques and the matrix effect affecting their detection and quantification in biological samples. Matrix suppression of the signal of cathinones has been previously observed in urine sample by LC-MS/MS. This study is aimed to use the standard addition method to overcome the plasma matrix effect on the quantification of cathinone and mephedrone by LC-MS/MS. Findings: The results showed the matrix effect for cathinone at lowest tested concentration (10 ng/ml) was significantly reduced from 210.9 to 133.7%, but not for mephedrone (from 196.8 to 191.9%) by using standard addition method. At the higher tested concentrations of samples, the matrix effects were significantly reduced for both cathinone and mephedrone by using standard addition technique. Conclusions: Standard addition quantitative technique can serve as an alternative quantitative method for LC-MS/MS when suitable internal standards are not available.
Existing drug discovery process follows a reductionist model of ″one-drug-one-gene-one-disease,″ ... more Existing drug discovery process follows a reductionist model of ″one-drug-one-gene-one-disease,″ which is not adequate to tackle complex diseases that involve multiple malfunctioned genes. The availability of big omics data offers new opportunities to transform the drug discovery process into a new paradigm of systems pharmacology that focuses on designing drugs to target molecular interaction networks instead of a single gene. Here, we develop a reliable multi-rank, multi-layered recommender system ANTENNA to mine large-scale chemical genomics and disease association data for the prediction of novel drug-gene-disease associations. ANTENNA integrates a novel tri-factorization based dual-regularized weighted and imputed One Class Collaborative Filtering (OCCF) algorithm tREMAP with a statistical framework that is based on Random Walk with Restart and can assess the reliability of a specific prediction. In the benchmark study, tREMAP clearly outperforms the single rank OCCF. We apply ...
Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion... more Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion products in wastewater to obtain information about exposure to drugs in defined population groups. We developed and validated an analytical method for the simultaneous determination of opioids (morphine, oxycodone, hydrocodone, oxymorphone and hydromorphone), and cannabinoids (D 9-tetrahydrocannabinol, 11-nor-9-carboxytetrahydrocannabinol (THCCOOH) and THCCOOH-glucuronide) in raw-influent wastewater samples by ultra-high performance liquid chromatography-tandem mass spectrometry. Method validation included linearity (5-1 000 ng/L for opioids, 10-1 000 ng/L for cannabinoids), imprecision (<21.2%), accuracy (83%-131%), matrix effect (from-35.1% to-14.7%) and extraction efficiency (25%-84%), limit of detection (1-5 ng/L) and quantification (5-10 ng/L) and auto-sampler stability (no loss detected). River and wastewater samples were collected in triplicate from different locations in New York City and stored at ¡20 C until analysis. Water from sewage overflow location tested positive for morphine (10.7 ng/L), oxycodone (4.2-23.5 ng/L), oxymorphone (4.8 ng/L) and hydromorphone (4.2 ng/L). Raw influent wastewater samples tested positive for morphine (133.0-258.3 ng/L), oxycodone (31.1-63.6 ng/L), oxymorphone (16.0-56.8 ng/L), hydromorphone (6.8-18.0 ng/L), hydrocodone (4.0-12.8 ng/L) and THCCOOH (168.2-772.0 ng/L). This method is sensitive and specific for opioids and marijuana determination in wastewater samples.
Mitomycin C (MC), a commonly used anticancer drug, induces DNA damage via DNA alkylation. Decarba... more Mitomycin C (MC), a commonly used anticancer drug, induces DNA damage via DNA alkylation. Decarbamoyl mitomycin C (DMC), another mitomycin lacking the carbamate at C10, generates similar lesions as MC. Interstrand cross-links (ICLs) are believed to be the lesions primarily responsible for the cytotoxicity of MC and DMC. The major ICL generated by MC (α-ICL) has a trans stereochemistry at the guanine-drug linkage whereas the major ICL from DMC (β-ICL) has the opposite, cis, stereochemistry. In addition, DMC can provoke strong p53-independent cell death. Our hypothesis is that the stereochemistry of the major unique β-ICL generated by DMC is responsible for this p53-independent cell death signaling. p53 gene is inactively mutated in more than half of human cancers. p21 WAF1/CIP1 known as a major effector of p53 is involved in p53-dependent and-independent control of cell proliferation and death. This study revealed the role of p21 WAF1/CIP1 on MC and DMC triggered cell damage. MCF-7 (p53-proficient) and K562 (p53-deficient) cells were used. Cell cycle distributions were shifted to the G1/S phase in MCF-7 treated with MC and DMC, but were shifted to the S phase in K562. p21 WAF1/CIP1 activation was observed in both cells treated with MC and DMC, and DMC triggered more significant activation. Knocking down p53 in MCF-7 did not attenuate MC and DMC induced p21 WAF1/CIP1 activation. The α-ICL itself was enough to cause p21 WAF1/CIP1 activation.
Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C... more Mitomycin C (MC) and Decarbamoylmitomycin C (DMC) - a derivative of MC lacking the carbamate on C10 - are DNA alkylating agents. Their cytotoxicity is attributed to their ability to generate DNA monoadducts as well as intrastrand and interstrand cross-links (ICLs). The major monoadducts generated by MC and DMC in tumor cells have opposite stereochemistry at carbon one of the guanine-mitosene bond: trans (or alpha) for MC and cis (or beta) for DMC. We hypothesize that local disruptions of DNA structure from trans or cis adducts are responsible for the different biochemical responses produced by MC and DMC. Access to DNA substrates bearing cis and trans MC/DMC lesions is essential to verify this hypothesis. Synthetic oligonucleotides bearing trans lesions can be obtained by bio-mimetic methods. However, this approach does not yield cis adducts. This report presents the first chemical synthesis of a cis mitosene DNA adduct. We also examined the stereopreference exhibited by the two drugs at the mononucleotide level by analyzing the formation of cis and trans adducts in the reaction of deoxyguanosine with MC or DMC using a variety of activation conditions. In addition, we performed Density Functional Theory calculations to evaluate the energies of these reactions. Direct alkylation under autocatalytic or bifunctional conditions yielded preferentially alpha adducts with both MC and DMC. DFT calculations showed that under bifunctional activation, the thermodynamically favored adducts are alpha, trans, for MC and beta, cis, for DMC. This suggests that the duplex DNA structure may stabilize/oriente the activated pro-drugs so that, with DMC, formation of the thermodynamically favored beta products are possible in a cellular environment.
Three cobalt(II) complexes based on 4'-chloro-2,2':6',2''-terpyridine (4'-Cltpy) have been synthe... more Three cobalt(II) complexes based on 4'-chloro-2,2':6',2''-terpyridine (4'-Cltpy) have been synthesized and structurally characterized by X-ray crystallography. The reaction with a 1:1 metal-to-ligand ratio in a mixed CH 2 Cl 2-MeOH solvent afforded the mononuclear complex Co(4'-Cltpy)Cl 2 (1) that mimicks the previously reported Cu(4'-Cltpy)Cl 2 , while altering the metal-to-ligand ratio to 2:1 under the same reaction conditions resulted in the formation of a different complex with a component of [Co(4'-Cltpy)Cl 2 ][Co 2 (4'-Cltpy) 2 Cl 4 ] (2), based on single crystal X-ray structural analysis. The presence of both a mononuclear molecule Co(4'-Cltpy)Cl 2 and dinuclear Cl-bridging Co 2 (4'-Cltpy) 2 Cl 4 in 2 was revealed. The replacement of CoCl 2 with Co(SCN) 2 under the same reaction conditions as for 1 gave a similar mononuclear Co(4'-Cltpy)(SCN) 2 (3). The cobalt(II) complexes along with the known copper analogue 4 were investigated for their in-vitro cytotoxic activity towards two human cancer cell lines, the human breast cancer (MCF-7) and leukemia (K562) cells, and distinct cytotoxicity was observed.
Previous studies point to quaternary assembly of dopamine transporters (DATs) in oligomers. Howev... more Previous studies point to quaternary assembly of dopamine transporters (DATs) in oligomers. However, it is not clear whether the protomers function independently in the oligomer. Is each protomer an entirely separate unit that takes up dopamine and is inhibited by drugs known to block DAT function? In this work, human embryonic kidney 293 cells were co-transfected with DAT constructs possessing differential binding affinities for the phenyltropane cocaine analog, [(3) H]WIN35,428. It was assessed whether the binding properties in co-expressing cells capable of forming hetero-oligomers differ from those in preparations obtained from mixed singly transfected cells where such oligomers cannot occur. A method is described that replaces laborious 'mixing' experiments with an in silico method predicting binding parameters from those observed for the singly expressed constructs. Among five pairs of constructs tested, statistically significant interactions were found between protome...
ABSTRACT A thiourea moiety has been introduced into a salen-type ligand scaffold to give a new un... more ABSTRACT A thiourea moiety has been introduced into a salen-type ligand scaffold to give a new unsymmetric ligand by CLICK chemistry. The cobalt(II) and nickel(II) complexes were prepared by a one-pot procedure and structurally characterized by X-ray crystallography. Both complexes are isomorphic and exhibit a tetra-coordinate metal center in a near square planar N2OS coordination environment. Intermolecular hydrogen bonds mediated by solvated methanol assemble the complexes into one-dimensional helical chains with P- and M-chirality. Cytotoxic activities of both complexes against the PC12 and HEK293 cells were studied.
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Papers by Shu-Yuan Cheng