Publications

Low-income women are at high risk of developing cervical cancer attributable not only to the higher prevalence of risk factors in this population but also to the lack of timely follow-up of abnormal Pap smears. This study evaluates the efficacy of an aggressive follow-up strategy. Women with abnormal Pap smear results after screening in a public hospital emergency department were randomly assigned to follow-up either by a case-managed approach using computerized tracking and universal colposcopy or by traditional care. The main outcome was the proportion of women receiving follow-up in 6 months. A secondary outcome was the proportion of women receiving follow-up by 6 months and diagnostic resolution in 18 months. Of 54 women in the intervention group, 65% kept at least one follow-up appointment in 6 months compared with 41% of the 54 women in the control group (P = 0.012). Half the women in the intervention group versus 19% of women in the control group had follow-up in 6 months and diagnostic resolution in 18 months (P = 0.001). After adjusting for age, initial Pap smear result, and race/ethnicity, the odds of having follow-up in 6 months were four times greater for women in the intervention group (odds ratio = 4.0; 95% confidence interval, 1.6-9.7), and the odds of having both follow-up in 6 months and diagnostic resolution in 18 months were more than six times greater (odds ratio = 6.5; 95% confidence interval, 2.4-17.8). This study demonstrates that an aggressive follow-up strategy significantly improves the rate of both initial follow-up and diagnostic resolution of abnormal Pap smears among low-income women with atypical squamous cells of undetermined significance and atypical glandular cells of undetermined significance when compared with traditional care.

The contamination of blood products by HIV in the early 1980s resulted in thousands of deaths among people with hemophilia in the United States and elsewhere. In the US, industry, government, physicians, and advocacy groups were implicated in this tragedy. In response to pleas from members of the US hemophilia community, the Institute of Medicine (IOM) of the National Academy of Science convened a public hearing to identify the institutional determinants of the HIV/AIDS epidemic among US hemophilia patients. The resulting IOM Report (1995) established a narrative of the crisis and indicated necessary improvements to the management of the US blood supply. The Report, however, failed to address the hemophilia community's demands for accountability and retribution. In this paper we explore the moral and social dimensions of this tragedy through narrative analysis of the original testimonies of hemophilia sufferers, interviews with some patients and their families, and a re-examination of the text of the IOM Report itself. We examine the process by which this crisis was addressed--through the discourses of science and law--and how it was ultimately framed as a failure of management and oversight rather than a moral failure of the for-profit health-care system. Thus, while the Report and its aftermath demonstrate powerfully how testimonials of suffering can influence public policy, by not addressing what is at stake for the victims--failure to protect patients in an era of increasingly commodified health care--it led to an exculpatory solution that obfuscated the moral dimensions of suffering.

The integrin alpha9 subunit forms a single heterodimer, alpha9beta1. The alpha9 subunit is most closely related to the alpha4 subunit, and like alpha4 integrins, alpha9beta1 plays an important role in leukocyte migration. The alpha4 cytoplasmic domain preferentially enhances cell migration and inhibits cell spreading, effects that depend on interaction with the adaptor protein, paxillin. To determine whether the alpha9 cytoplasmic domain has similar effects, a series of chimeric and deleted alpha9 constructs were expressed in Chinese hamster ovary cells and tested for their effects on migration and spreading on an alpha9beta1-specific ligand. Like alpha4, the alpha9 cytoplasmic domain enhanced cell migration and inhibited cell spreading. Paxillin also specifically bound the alpha9 cytoplasmic domain and to a similar level as alpha4. In paxillin(-/-) cells, alpha9 failed to inhibit cell spreading as expected but surprisingly still enhanced cell migration. Further, mutations that abolished the alpha9-paxillin interaction prevented alpha9 from inhibiting cell spreading but had no effect on alpha9-dependent cell migration. These findings suggest that the mechanisms by which the cytoplasmic domains of integrin alpha subunits enhance migration and inhibit cell spreading are distinct and that the alpha9 and alpha4 cytoplasmic domains, despite sequence and functional similarities, enhance cell migration by different intracellular signaling pathways.

Interleukin (IL)-13, a cytokine released by T lymphocytes during immediate hypersensitivity responses, is a central mediator of asthma. Because IL-13 induces phenotypic features of asthma in mice deficient in T and B lymphocytes, it is likely that this cytokine contributes to the development of asthma by acting directly on resident airway cells. To analyze the global effects of IL-13 on gene expression in airway cells that could contribute to the phenotypic features of asthma, we used Genechip HuGene FL arrays (Affymetrix, Santa Clara, CA) that contain probes for approximately 6,500 human genes. Despite activating a common signaling pathway, IL-13 induced dramatically different patterns of gene expression in primary cultures of airway epithelial cells, airway smooth muscle cells, and lung fibroblasts, with little overlap among cell types. The most prominent effects of IL-13 were on airway smooth muscle, but several genes induced in airway epithelial cells and fibroblasts are also candidates that may contribute to phenotypic features of asthma. These results suggest that the in vivo response to IL-13 in the airways likely results from a combination of distinct effects on each of several resident airway cell types.

As an initial approach toward the characterization of the phosphorylation of cumene hydroperoxide (CuOOH)-inactivated cytochrome P450 (CYP3A4, the major human liver drug-metabolizing enzyme) and its role in the degradation of the inactivated protein, we have identified one of the major participating cytosolic kinase(s) as rat liver cytosolic protein kinase C (PKC) with the use of specific and general kinase inhibitors. Accordingly, we employed a model phosphorylation system consisting of purified PKC, gamma-S-[(32)P]ATP, and either native or CuOOH-inactivated purified recombinant His(6)-tagged CYP3A4. Lysylendoprotease (Lys)-C digestion of the phosphorylated CuOOH-inactivated CYP3A4(His)(6) followed by HPLC-peptide mapping and mass spectrometric (LC/MS/MS) analyses led to the isolation and the unambiguous identification of two PKC-phosphorylated CYP3A4 peptides: E(258)SRLEDT(p)QK(266) and F(414)LPERFS(p)K(421). Similar analyses of the PKC-phosphorylated native enzyme predominantly yielded E(258)SRLEDT(p)QK(266) as the phosphorylated peptide. Studies are currently in progress to determine whether phosphorylation of any or both of these peptides is required for the Ub-dependent 26S proteasomal degradation of CuOOH-inactivated CYP3A4.