John Roman - Academia.edu (original) (raw)
Papers by John Roman
Cancer research, 1987
In an attempt to elucidate the molecular basis for the decrease in rat liver carcinogenicity and ... more In an attempt to elucidate the molecular basis for the decrease in rat liver carcinogenicity and DNA-alkylating ability that accompanies deuteration of N-nitrosodimethylamine (NDMA), NDMA and its fully deuterated analogue ([2H6]NDMA) were incubated with acetone-induced rat liver microsomes. Rates for the competing metabolic routes, denitrosation and demethylation, were determined from colorimetric data on nitrite and formaldehyde generation, respectively. The Vmax calculated for demethylation of NDMA was 7.9 nmol/min/mg, while that for denitrosation was 0.83 nmol/min/mg. Deuteration of NDMA did not significantly change the Vmax for either pathway, but it did increase the Km for demethylation from 0.06 to 0.3 mM. The Km for denitrosation was also increased from 0.06 to 0.3 mM on deuteration, as determined by incubating an equimolar mixture of amino-15N-labeled NDMA with [2H6]NDMA and measuring the methyl[15N]amine:[2H3]methylamine ratio by derivatization-gas chromatography-mass spect...
PsycEXTRA Dataset, 2000
Abstract While a large body of empirical research indicates that marriage is associated with crim... more Abstract While a large body of empirical research indicates that marriage is associated with criminal activity, to date little research exists on the effects of relationship status on a population of offenders returning to their communities. This study uses data on over 650 ...
Noise pollution and industrial pollution are well-known phenomena. The more technical term for su... more Noise pollution and industrial pollution are well-known phenomena. The more technical term for such pollution is 'externalities'. In both instances, the producer of the pollution creates a social cost that is borne by others. Unwilling recipients, such as residents on a noisy airport flight- path or downstream recipients of water pollution, bear the cost. For some types of pollution, such
This study evaluates the impact of the Maryland Reentry Partnership Initiative (REP) on crime in ... more This study evaluates the impact of the Maryland Reentry Partnership Initiative (REP) on crime in Baltimore between 2001 and 2005. It compares 229 REP clients to a contemporaneous cohort of 370 prisoners released to non-REP neighborhoods in Baltimore City. The quasi-experimental ...
Research on cost-benefit analysis of situational crime pre- vention is examined and found wanting... more Research on cost-benefit analysis of situational crime pre- vention is examined and found wanting. The few existing studies do not accurately represent the likely benefits of the situational approach. While measures of non-monetary crime costs are improving, at least four other key areas warrant more attention: First, "routine savings" derive from routine precautions. Second, models of victim (producer) and offender
all current or past members of the ACTION team, were extremely helpful throughout the study and u... more all current or past members of the ACTION team, were extremely helpful throughout the study and uniformly accommodated our many requests for assistance. Ed Zedlewski and Maggie Heisler, with the National Institute of Justice, provided guidance and insights that greatly improved the project's design and execution, and Sandy Woerle helped guide us through the final stages of the project. Joe Donnermeyer offered many helpful ideas for improving the research design. We give special thanks to the many farmers who participated in the study, without whom there would not have been to report.
Gastroenterology, 2006
Abbreviations used in this paper: ELISA, enzyme-linked immunosorbent assay; IMAC3, immobilized me... more Abbreviations used in this paper: ELISA, enzyme-linked immunosorbent assay; IMAC3, immobilized metal affinity capture; SELDI-TOF MS, surface-enhanced laser desorption/ionization time-of-flight mass spectrometry; UICC, International Union Against Cancer; WCX2, weak cationic exchange.
Children and Youth Services Review, 2011
... United States. c Temple University, Department of Criminal Justice, Gladfelter Hall, 5th Floo... more ... United States. c Temple University, Department of Criminal Justice, Gladfelter Hall, 5th Floor, 1115 Polett Walk, Philadelphia, PA 19122, United States. Available online 14 June 2011. Abstract. Evaluating comprehensive, interagency ...
Chemical Research in Toxicology, 1996
triazenes have been shown to be effective cancer chemotherapeutic agents in a number of biologica... more triazenes have been shown to be effective cancer chemotherapeutic agents in a number of biological systems. Because of their chemical stability, it is likely that their activity in vivo is the result of a metabolic activation process. Previous studies have shown that 1-(2-chloroethyl)-3-methyl-3-(methylcarbamoyl)triazene (CMM) and 1-(2-chloroethyl)-3benzyl-3-(methylcarbamoyl)triazene (CBzM) are metabolized by rat liver microsomes in the presence of NADPH to yield the ((hydroxymethyl)carbamoyl)triazene analogs of the parent compounds. The present studies show that both compounds are also oxidized at the chloroethyl substituent to yield chloroacetaldehyde and a substituted urea. In the case of CBzM metabolism, 47% of the metabolized parent compound was recovered as benzylmethylurea, 8% was recovered as benzylurea, and 26% was recovered as the ((hydroxymethyl)carbamoyl)triazene and carbamoyltriazene metabolites. These results suggest that the chloroethyl group is the favored initial site of metabolism. In reaction mixtures containing intitial concentrations of 300 µM CBzM, 78 µM chloroacetaldehyde was produced, as compared to 58 µM chloroacetaldehyde produced from the metabolism of 300 µM CMM. The formation of chloroacetaldehyde, a known mutagenic DNA alkylating agent, may explain the biological activity of these compounds.
Chemical Research in Toxicology, 1989
The characterization of eight benzo[a]pyrene-deoxyribonucleoside adducts derived from reaction of... more The characterization of eight benzo[a]pyrene-deoxyribonucleoside adducts derived from reaction of the anti-dihydrodiol epoxide and deoxyguanylic and deoxyadenylic acids is described. It is reported that the epoxide ring is opened by the purine amino groups to yield similar amounts of both cis and trans products. NMR data show that the 7- and 8-hydroxyl groups are pseudodiaxial in the cis products and pseudodiequatorial in the trans products, and we suggest that these products arise from reaction with the diaxial and diequatorial conformers of the dihydrodiol epoxides, respectively. The chiral nature of the interactions of these metabolites with DNA restricts the range of products formed with this macromolecule, and a trans product with deoxyguanosine is the major product formed with either enantiomer of the anti-dihydrodiol epoxide.
Analytical Chemistry, 2007
Endogenous estrogen plays a key role in the development of human breast cancer, yet the contribut... more Endogenous estrogen plays a key role in the development of human breast cancer, yet the contribution of specific estrogen metabolites and patterns of estrogen metabolism remains unclear. To determine their individual and joint roles in breast carcinogenesis, it is necessary to be able to measure quantitatively each estrogen metabolite in epidemiologic and clinical biospecimens. In this report, we detail a sensitive, specific, accurate, and precise high-performance liquid chromatography-tandem mass spectrometry method utilizing selected reaction monitoring for measuring the absolute quantities of free (unconjugated) and total (conjugated + unconjugated) endogenous estrogens and estrogen metabolites in human serum from premenopausal and postmenopausal women. The method requires a simple sample preparation and only 0.5 mL of serum, yet is capable of quantifying simultaneously 15 estrogens and estrogen metabolites (EM): estrone and its 2-, 4-, and 16alpha-hydroxy and 2- and 4-methoxy derivatives; 2-hydroxyestrone-3-methyl ether; 17beta-estradiol and its 2-hydroxy and 2- and 4-methoxy derivatives; and estriol, 17-epiestriol, 16-ketoestradiol, and 16-epiestriol. The lower limit of quantitation for each EM was 0.4 pg on-column, equivalent to 8 pg/mL (26.5-29.6 fmol/mL) in the original serum sample. Calibration curves were linear over a 10(3)-fold concentration range. For a stripped serum sample containing 8 pg/mL of each EM, accuracy (percent recovery of a known added amount) ranged from 91 to 113%. Intrabatch precision (including hydrolysis, extraction, and derivatization steps) ranged from 7 to 30% relative standard deviation (RSD), and interbatch precision ranged from 8 to 29% RSD. Since distinct roles have been proposed for many of these estrogen metabolites, an accurate, precise, sensitive, and specific method for measuring their levels in circulation should suggest new approaches to breast cancer prevention, screening, and treatment.
Analytical Chemistry, 2005
A sensitive, specific, accurate, and precise high-performance liquid chromatography-electrospray ... more A sensitive, specific, accurate, and precise high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for measuring the absolute quantities of 15 endogenous estrogens and their metabolites in human urine has been developed and validated. The method requires a single hydrolysis/extraction/derivatization step and only 0.5 mL of urine, yet is capable of simultaneously quantifying estrone and its 2-, 4-methoxy and 2-, 4-, and 16alpha-hydroxy derivatives, and 2-hydroxyestrone-3-methyl ether; estradiol and its 2-, 4-methoxy and 2-, 16alpha-hydroxy derivatives, 16-epiestriol, 17-epiestriol, and 16-ketoestradiol in pre- and postmenopausal women as well as men. Standard curves are linear over a 10(3)-fold concentration range with the standard error of the estimate (SEE) and the relative standard error of the estimate (RSEE) for the linear regression line ranging from 0.0131 to 0.1760 and 1.2 to 7.3%, respectively. The lower limit of quantitation for each estrogen is 0.02 ng/0.5 mL urine sample (2 pg on column), with the percent recovery of a known added amount of compound (accuracy) of 96-107% and an overall precision, including the hydrolysis, extraction, and derivatization steps, of 1-5% relative standard deviation (RSD) for samples prepared concurrently and 1-12% RSD for samples prepared in separate batches. Since individual patterns of estrogen metabolism may influence the risk of breast cancer, accurate, precise, and specific measurement of endogenous estrogen metabolites in biological matrixes will facilitate future research on breast cancer prevention, screening, and treatment.
This publication was prepared under the leadership of an editorial group including the following:... more This publication was prepared under the leadership of an editorial group including the following: Kristin B. Schubert ROBERT WOOD JOHNSON FOUNDATION, PRINCETON, NJ Laura Nissen RECLAIMING FUTURES, PORTLAND, OR Dan Merrigan BOSTON UNIVERSITY ...
Cancer research, 1987
In an attempt to elucidate the molecular basis for the decrease in rat liver carcinogenicity and ... more In an attempt to elucidate the molecular basis for the decrease in rat liver carcinogenicity and DNA-alkylating ability that accompanies deuteration of N-nitrosodimethylamine (NDMA), NDMA and its fully deuterated analogue ([2H6]NDMA) were incubated with acetone-induced rat liver microsomes. Rates for the competing metabolic routes, denitrosation and demethylation, were determined from colorimetric data on nitrite and formaldehyde generation, respectively. The Vmax calculated for demethylation of NDMA was 7.9 nmol/min/mg, while that for denitrosation was 0.83 nmol/min/mg. Deuteration of NDMA did not significantly change the Vmax for either pathway, but it did increase the Km for demethylation from 0.06 to 0.3 mM. The Km for denitrosation was also increased from 0.06 to 0.3 mM on deuteration, as determined by incubating an equimolar mixture of amino-15N-labeled NDMA with [2H6]NDMA and measuring the methyl[15N]amine:[2H3]methylamine ratio by derivatization-gas chromatography-mass spect...
PsycEXTRA Dataset, 2000
Abstract While a large body of empirical research indicates that marriage is associated with crim... more Abstract While a large body of empirical research indicates that marriage is associated with criminal activity, to date little research exists on the effects of relationship status on a population of offenders returning to their communities. This study uses data on over 650 ...
Noise pollution and industrial pollution are well-known phenomena. The more technical term for su... more Noise pollution and industrial pollution are well-known phenomena. The more technical term for such pollution is 'externalities'. In both instances, the producer of the pollution creates a social cost that is borne by others. Unwilling recipients, such as residents on a noisy airport flight- path or downstream recipients of water pollution, bear the cost. For some types of pollution, such
This study evaluates the impact of the Maryland Reentry Partnership Initiative (REP) on crime in ... more This study evaluates the impact of the Maryland Reentry Partnership Initiative (REP) on crime in Baltimore between 2001 and 2005. It compares 229 REP clients to a contemporaneous cohort of 370 prisoners released to non-REP neighborhoods in Baltimore City. The quasi-experimental ...
Research on cost-benefit analysis of situational crime pre- vention is examined and found wanting... more Research on cost-benefit analysis of situational crime pre- vention is examined and found wanting. The few existing studies do not accurately represent the likely benefits of the situational approach. While measures of non-monetary crime costs are improving, at least four other key areas warrant more attention: First, "routine savings" derive from routine precautions. Second, models of victim (producer) and offender
all current or past members of the ACTION team, were extremely helpful throughout the study and u... more all current or past members of the ACTION team, were extremely helpful throughout the study and uniformly accommodated our many requests for assistance. Ed Zedlewski and Maggie Heisler, with the National Institute of Justice, provided guidance and insights that greatly improved the project's design and execution, and Sandy Woerle helped guide us through the final stages of the project. Joe Donnermeyer offered many helpful ideas for improving the research design. We give special thanks to the many farmers who participated in the study, without whom there would not have been to report.
Gastroenterology, 2006
Abbreviations used in this paper: ELISA, enzyme-linked immunosorbent assay; IMAC3, immobilized me... more Abbreviations used in this paper: ELISA, enzyme-linked immunosorbent assay; IMAC3, immobilized metal affinity capture; SELDI-TOF MS, surface-enhanced laser desorption/ionization time-of-flight mass spectrometry; UICC, International Union Against Cancer; WCX2, weak cationic exchange.
Children and Youth Services Review, 2011
... United States. c Temple University, Department of Criminal Justice, Gladfelter Hall, 5th Floo... more ... United States. c Temple University, Department of Criminal Justice, Gladfelter Hall, 5th Floor, 1115 Polett Walk, Philadelphia, PA 19122, United States. Available online 14 June 2011. Abstract. Evaluating comprehensive, interagency ...
Chemical Research in Toxicology, 1996
triazenes have been shown to be effective cancer chemotherapeutic agents in a number of biologica... more triazenes have been shown to be effective cancer chemotherapeutic agents in a number of biological systems. Because of their chemical stability, it is likely that their activity in vivo is the result of a metabolic activation process. Previous studies have shown that 1-(2-chloroethyl)-3-methyl-3-(methylcarbamoyl)triazene (CMM) and 1-(2-chloroethyl)-3benzyl-3-(methylcarbamoyl)triazene (CBzM) are metabolized by rat liver microsomes in the presence of NADPH to yield the ((hydroxymethyl)carbamoyl)triazene analogs of the parent compounds. The present studies show that both compounds are also oxidized at the chloroethyl substituent to yield chloroacetaldehyde and a substituted urea. In the case of CBzM metabolism, 47% of the metabolized parent compound was recovered as benzylmethylurea, 8% was recovered as benzylurea, and 26% was recovered as the ((hydroxymethyl)carbamoyl)triazene and carbamoyltriazene metabolites. These results suggest that the chloroethyl group is the favored initial site of metabolism. In reaction mixtures containing intitial concentrations of 300 µM CBzM, 78 µM chloroacetaldehyde was produced, as compared to 58 µM chloroacetaldehyde produced from the metabolism of 300 µM CMM. The formation of chloroacetaldehyde, a known mutagenic DNA alkylating agent, may explain the biological activity of these compounds.
Chemical Research in Toxicology, 1989
The characterization of eight benzo[a]pyrene-deoxyribonucleoside adducts derived from reaction of... more The characterization of eight benzo[a]pyrene-deoxyribonucleoside adducts derived from reaction of the anti-dihydrodiol epoxide and deoxyguanylic and deoxyadenylic acids is described. It is reported that the epoxide ring is opened by the purine amino groups to yield similar amounts of both cis and trans products. NMR data show that the 7- and 8-hydroxyl groups are pseudodiaxial in the cis products and pseudodiequatorial in the trans products, and we suggest that these products arise from reaction with the diaxial and diequatorial conformers of the dihydrodiol epoxides, respectively. The chiral nature of the interactions of these metabolites with DNA restricts the range of products formed with this macromolecule, and a trans product with deoxyguanosine is the major product formed with either enantiomer of the anti-dihydrodiol epoxide.
Analytical Chemistry, 2007
Endogenous estrogen plays a key role in the development of human breast cancer, yet the contribut... more Endogenous estrogen plays a key role in the development of human breast cancer, yet the contribution of specific estrogen metabolites and patterns of estrogen metabolism remains unclear. To determine their individual and joint roles in breast carcinogenesis, it is necessary to be able to measure quantitatively each estrogen metabolite in epidemiologic and clinical biospecimens. In this report, we detail a sensitive, specific, accurate, and precise high-performance liquid chromatography-tandem mass spectrometry method utilizing selected reaction monitoring for measuring the absolute quantities of free (unconjugated) and total (conjugated + unconjugated) endogenous estrogens and estrogen metabolites in human serum from premenopausal and postmenopausal women. The method requires a simple sample preparation and only 0.5 mL of serum, yet is capable of quantifying simultaneously 15 estrogens and estrogen metabolites (EM): estrone and its 2-, 4-, and 16alpha-hydroxy and 2- and 4-methoxy derivatives; 2-hydroxyestrone-3-methyl ether; 17beta-estradiol and its 2-hydroxy and 2- and 4-methoxy derivatives; and estriol, 17-epiestriol, 16-ketoestradiol, and 16-epiestriol. The lower limit of quantitation for each EM was 0.4 pg on-column, equivalent to 8 pg/mL (26.5-29.6 fmol/mL) in the original serum sample. Calibration curves were linear over a 10(3)-fold concentration range. For a stripped serum sample containing 8 pg/mL of each EM, accuracy (percent recovery of a known added amount) ranged from 91 to 113%. Intrabatch precision (including hydrolysis, extraction, and derivatization steps) ranged from 7 to 30% relative standard deviation (RSD), and interbatch precision ranged from 8 to 29% RSD. Since distinct roles have been proposed for many of these estrogen metabolites, an accurate, precise, sensitive, and specific method for measuring their levels in circulation should suggest new approaches to breast cancer prevention, screening, and treatment.
Analytical Chemistry, 2005
A sensitive, specific, accurate, and precise high-performance liquid chromatography-electrospray ... more A sensitive, specific, accurate, and precise high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for measuring the absolute quantities of 15 endogenous estrogens and their metabolites in human urine has been developed and validated. The method requires a single hydrolysis/extraction/derivatization step and only 0.5 mL of urine, yet is capable of simultaneously quantifying estrone and its 2-, 4-methoxy and 2-, 4-, and 16alpha-hydroxy derivatives, and 2-hydroxyestrone-3-methyl ether; estradiol and its 2-, 4-methoxy and 2-, 16alpha-hydroxy derivatives, 16-epiestriol, 17-epiestriol, and 16-ketoestradiol in pre- and postmenopausal women as well as men. Standard curves are linear over a 10(3)-fold concentration range with the standard error of the estimate (SEE) and the relative standard error of the estimate (RSEE) for the linear regression line ranging from 0.0131 to 0.1760 and 1.2 to 7.3%, respectively. The lower limit of quantitation for each estrogen is 0.02 ng/0.5 mL urine sample (2 pg on column), with the percent recovery of a known added amount of compound (accuracy) of 96-107% and an overall precision, including the hydrolysis, extraction, and derivatization steps, of 1-5% relative standard deviation (RSD) for samples prepared concurrently and 1-12% RSD for samples prepared in separate batches. Since individual patterns of estrogen metabolism may influence the risk of breast cancer, accurate, precise, and specific measurement of endogenous estrogen metabolites in biological matrixes will facilitate future research on breast cancer prevention, screening, and treatment.
This publication was prepared under the leadership of an editorial group including the following:... more This publication was prepared under the leadership of an editorial group including the following: Kristin B. Schubert ROBERT WOOD JOHNSON FOUNDATION, PRINCETON, NJ Laura Nissen RECLAIMING FUTURES, PORTLAND, OR Dan Merrigan BOSTON UNIVERSITY ...