Certain HIV-encoded proteins modify host-cell gene expression in a manner that facilitates viral replication. These activities may contribute to low-level viral replication in nonproliferating cells. Through the use of oligonucleotide microarrays and high-throughput Western blotting we demonstrate that one of these proteins, gp120, induces the expression of cytokines, chemokines, kinases, and transcription factors associated with antigen-specific T cell activation in the absence of cellular proliferation. Examination of transcriptional changes induced by gp120 in freshly isolated peripheral blood mononuclear cells and monocyte-derivedmacrophages reveals a broad and complex transcriptional program conducive to productive infection with HIV. Observations include the induction of nuclear factor of activated T cells, components of the RNA polymerase II complex including TFII D, proteins localized to the plasma membrane, including several syntaxins, and members of the Rho protein family, including Cdc 42. These observations provide evidence that envelope-mediated signaling contributes to the productive infection of HIV in suboptimally activated T cells.H IV preferentially replicates in proliferating CD4 ϩ T cells(1). However recent evidence suggests that, in vivo, resting and suboptimally activated T cells may serve as targets for low-level productive infection in the absence of cellular proliferation (2-5). Infection in this manner may contribute to the establishment and͞or maintenance of persistent viral reservoirs that currently prevent the eradication of virus. To productively infect suboptimally activated CD4 ϩ T cells, HIV must overcome post-entry barriers to replication (6-8).DNA microarrays have been used to characterize the effect of HIV on target cell transcription (9, 10); in one microarray-based study, HIV Nef was shown to diminish barriers to viral replication by mimicking antigen-specific T cell proliferation signals (11,12). It has been suggested that HIV gp120 also facilitates replication in suboptimally activated cells (12-15). Gp120 transduces near-simultaneous signals through CD4 (16), a component of the T cell receptor complex, and CCR5, a chemokine receptor (17)(18)(19). In vivo concentrations of gp120 (20, 21) fall within the range required to induce signaling in vitro (17)(18)(19)22). To provide a more complete picture of the complex cascade of signals induced by gp120, we treated freshly isolated peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages (MDMs) with an envelope derived from a CCR5-using virus and measured temporal changes in the levels of mRNA by using Affymetrix (Santa Clara, CA) U95A oligonucleotide microarrays that include probes encompassing Ϸ12,600 genes. In addition, we used a high-throughput Western blot analysis that allowed us to screen protein lysates with 800 monoclonal antibodies. The gp120 used was derived from JR-FL, a CCR5-tropic molecular clone obtained from a minimally passaged viral isolate (23). We used concentrations of envelope near or bel...

In this small data set, FFDM appears to be slightly more sensitive than digital breast tomosynthesis for the detection of calcification. However, diagnostic performance as measured by area under the curve using BI-RADS was not significantly different. With improvements in processing algorithms and display, digital breast tomosynthesis could potentially be improved for this purpose.

Purpose:To assess interpretation performance and radiation dose when two-dimensional synthesized mammography (SM) images versus standard full-field digital mammography (FFDM) images are used alone or in combination with digital breast tomosynthesis images. Materials and Methods:A fully crossed, mode-balanced multicase (n = 123), multireader (n = 8), retrospective observer performance study was performed by using deidentified images acquired between 2008 and 2011 with institutional review board approved, HIPAA-compliant protocols, during which each patient signed informed consent. The cohort included 36 cases of biopsy-proven cancer, 35 cases of biopsy-proven benign lesions, and 52 normal or benign cases (Breast Imaging Reporting and Data System [BI-RADS] score of 1 or 2) with negative 1-year follow-up results. Accuracy of sequentially reported probability of malignancy ratings and seven-category forced BI-RADS ratings was evaluated by using areas under the receiver operating characteristic curve (AUCs) in the random-reader analysis. Results:Probability of malignancy-based mean AUCs for SM and FFDM images alone was 0.894 and 0.889, respectively (difference, 20.005; 95% confidence interval [CI]: 20.062, 0.054; P = .85). Mean AUC for SM with tomosynthesis and FFDM with tomosynthesis was 0.916 and 0.939, respectively (difference, 0.023; 95% CI: 20.011, 0.057; P = .19). In terms of the reader-specific AUCs, five readers performed better with SM alone versus FFDM alone, and all eight readers performed better with combined FFDM and tomosynthesis (absolute differences from 0.003 to 0.052). Similar results were obtained by using a nonparametric analysis of forced BI-RADS ratings.

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Rationale and Objective To assess the interaction between the availability of prior examinations and digital breast tomosynthesis (DBT) in decisions to recall a woman during interpretation of mammograms. Materials and Methods Eight radiologists independently interpreted twice 36 mammography examinations, each of which had current and prior full field digital mammography images (FFDM) and DBT under a HIPPA compliant IRB approved protocol (written consent waived). During the first reading three sequential ratings were provided using FFDM only followed by FFDM+ DBT followed by FFDM+DBT+priors. The second reading included FFDM only, then FFDM+priors, then FFDM+priors+DBT. Twenty two benign cases clinically recalled, 12 negative/benign examinations (not recalled) and two verified cancer cases were included. Recall recommendations and interaction between the effect of priors and DBT on decisions were assessed (p=0.05 significance level) using generalized linear model (proc glimmix, SAS. V.9.3., Cary, NC) accounting for case and reader variability. Results Average recall rates in non-cancer cases were significantly reduced (51%; p<0.001) with the addition of DBT and with addition of priors (23%; p=0.01). In absolute terms, the addition of DBT to FFDM reduced the recall rates from 0.67 to 0.42 and from 0.54 to 0.27 when DBT was available before and after priors, respectively. Recall reductions were from 0.64 to 0.54 and from 0.42 to 0.33 when priors were available before and after DBT, respectively. Regardless of the sequence in presentation, there were no statistically significant interactions between the effect of availability of DBT and priors (p=0.80). Conclusion Availability of both priors and DBT are independent, primary factors in reducing recall recommendations during mammographic interpretations.