Redox Reactions of the Pyranopterin System of the Molybdenum Cofactor

This work provides the first extensive study of the redox reactivity of the pyranopterin system that is a component of the catalytic site of all molybdenum and tungsten enzymes possessing molybdopterin. The pyranopterin system possesses certain characteristics typical of tetrahydropterins, such as a reduced pyrazine ring; however, it behaves as a dihydropterin in redox reactions with oxidants. Titrations using ferricyanide and dichloroindophenol (DCIP) prove a 2e(-)/2H(+) stoichiometry for pyranopterin oxidations. Oxidations of pyranopterin by Fe(CN)(6)(3-) or DCIP are slower than tetrahydropterin oxidation under a variety of conditions, but are considerably faster than observed for oxidations of dihydropterin. The rate of pyranopterin oxidation by DCIP was studied in a variety of media. In aqueous buffered solution the pyranopterin oxidation rate has minimal pH dependence, whereas the rate of tetrahydropterin oxidation decreases 100-fold over the pH range 7.4-8.5. Although pyranopterin reacts as a dihydropterin with oxidants, it resists further reduction to a tetrahydropterin. No reduction was achieved by catalytic hydrogenation, even after several days. The reducing ability of the commonly used biological reductants dithionite and methyl viologen radical cation was investigated, but experiments showed no evidence of pyranopterin reduction by any of these reducing agents. This study illustrates the dual personalities of pyranopterin and underscores the unique place that the pyranopterin system holds in the spectrum of pterin redox reactions. The work presented here has important implications for understanding the biosynthesis and reaction chemistry of the pyranopterin cofactor in molybdenum and tungsten enzymes

The Association Between Multiple Domains of Discriminations and Self-Assessed Health: A Multilevel Analysis of Latinos and Blacks in Four Low-Income New York City Neighborhoods

Objective. This study examines the association between discrimination due to race and other attributes (e.g., sex, age) and self-assessed mental and physical health among Latinos and blacks. Data Source. Latino and black adult participants (n5873) identified by randomdigit dialing were interviewed by telephone in four low-income neighborhoods in New York City: the South Bronx, East Harlem, Central Harlem, and Bedford-Stuyvesant. Study Design. In this cross-sectional study, generalized estimating equations were used to fit multilevelmultivariablemodels to test the association between discrimination and poor mental and physical health while controlling for socioeconomic status, access to health care, social support, smoking, and the racial and ethnic composition of each neighborhood. Principal Findings. Discrimination due to race and discrimination due to other attributes were associated with poor self-assessed mental but not physical health in separate multivariable models. Persons who experienced multiple domains of discrimination had a greater probability of reporting poor mental health than persons who experienced no discrimination. Conclusions. Discrimination due to race and other attributes was a significant correlate of mental health among Latinos and blacks independent of other accepted determinants of health.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40298/2/Stuber_The Association Between Multiple Domains_2003.pd

Project VIVA: A multi-level community-based intervention to increase influenza vaccination rates among hard-to-reach populations in New York City

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/60340/1/coady_project viva_2008.pd

Preliminary Evidence of Health Care Provider Support for Naloxone Prescription as Overdose Fatality Prevention Strategy in New York City

Preliminary research suggests that naloxone (Narcan), a short-acting opiate antagonist, could be provided by prescription or distribution to heroin users to reduce the likelihood of fatality from overdose. We conducted a random postal survey of 1,100 prescription-authorized health care providers in New York City to determine willingness to prescribe naloxone to patients at risk of an opiate overdose. Among 363 nurse practitioners, physicians, and physician assistants responding, 33.4% would consider prescribing naloxone, and 29.4% were unsure. This preliminary study suggests that a substantial number of New York City health care providers would prescribe naloxone for opiate overdose prevention.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40255/2/Coffin_Preliminary Evidence of Health Care Provider_2003.pd

Gender differences in sexual behaviors, sexual partnerships, and HIV among drug users in New York City

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48789/1/absalon_gender differences in sexual behaviors_2006.pd

Neighborhood-Level Correlates of Consistent Condom Use among Men Who have Sex with Men: A Multi-Level Analysis

http://deepblue.lib.umich.edu/bitstream/2027.42/61277/1/Frye.et.al.Neighborhood-LevelCorrelatesofConsistantCondomUse.pd

A Comparison of HIV Seropositive and Seronegative Young Adult Heroin- and Cocaine- Using Men Who Have Sex with Men in New York City, 2000-2003

The purpose of this analysis was to determine the prevalence and correlates of HIV infection among a street-recruited sample of heroin- and cocaine-using men who have sex with men (MSM). Injection (injecting â¤3 years) and non-injection drug users (heroin, crack, and/or cocaine use <10 years) between 18 and 40 years of age were simultaneously street-recruited into two cohort studies in New York City, 2000â2003, by using identical recruitment techniques. Baseline data collected among young adult men who either identified as gay/bisexual or reported ever having sex with a man were used for this analysis. Nonparametric statistics guided interpretation. Of 95 heroin/ cocaine-using MSM, 25.3% tested HIV seropositive with 75% reporting a previous HIV diagnosis. The majority was black (46%) or Hispanic (44%), and the median age was 28 years (range 18â40). HIV-seropositive MSM were more likely than seronegatives to be older and to have an HIV-seropositive partner but less likely to report current homelessness, illegal income, heterosexual identity, multiple sex partners, female partners, and sex for money/drug partners than seronegatives. These data indicate high HIV prevalence among street-recruited, drug-using MSM compared with other injection drug use (IDU) subgroups and drug-using MSM; however, lower risk behaviors were found among HIV seropositives compared with seronegatives. Large-scale studies among illicit drug-using MSM from more marginalized neighborhoods are warranted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40372/2/Fuller_A Comparison of HIV Seropositive and Seronegative_2005.pd

Determinants of influenza vaccination in hard-to-reach urban populations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/40392/1/bryant_determinants of influenza vaccination_2006.pd

Predictors of influenza vaccination in an urban community during a national shortage

http://deepblue.lib.umich.edu/bitstream/2027.42/61292/1/phillips caesar e, coady mh, blaney s, ompad dc, galea s, predictors of influenza vaccination in an urban community during a national shortage.pd

Explaining racial disparities in incidence of and survival from out-of-hospital cardiac arrest

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55494/1/galea_explaining racial disparities_2007.pd