Routine HIV testing program in the University Infectious Diseases Centre in Lithuania: a four-year analysis.

BACKGROUND: HIV transmission remains a major concern in Eastern Europe, and too many people are diagnosed late. Expanded testing strategies and early and appropriate access to care are required. Infectious disease departments might be targets for expanded HIV testing owing to the intense passage of key patient populations that carry indicators of HIV disease. Our objective was to evaluate the feasibility and clinical effectiveness of a fully integrated, opt-out routine, rapid HIV testing program. METHODS: A retrospective four-year study of a screening program was conducted from 2010 through 2014. The program was divided into two periods: from 2010 to 2012 (pilot study) and from 2013 to 2014. The pilot study consisted of routine HIV testing of patients aged 18-55 that were hospitalized in one department. In the second period, all inpatients aged 18-65 were eligible. Targeted testing was conducted in the other inpatient department during the pilot study and the outpatient department during both periods. RESULTS: During the pilot study, 2203 patients were hospitalized, 1314 (59.6%) were eligible, 954 (72.6%) were tested, and 3 (0.31%) were newly diagnosed HIV-positive. In the second period, 4911 patients were hospitalized, 3727 (75.9%) were eligible, 3303 (88.6%) were tested, and 7 (0.21%) were HIV-positive. In total, 2800 targeted tests were performed, and 4 (0.14%) patients tested positive with newly discovered HIV. All 14 newly diagnosed patients were provided with care. Comparing cumulative groups of routine and targeted testing, the HIV prevalence was 0.23% vs. 0.14% (p = 0.40) and was above the reported cost-effectiveness threshold of 0.1% (p = 0.012). A lower proportion of advanced disease and a higher proportion of heterosexually transmitted infection were found in the routine testing group. CONCLUSION: Routine HIV testing in admissions of infectious diseases is acceptable, feasible, sustainable and clinically effective. Compared to targeted testing, routine testing helped to discover more patients in earlier stages and those with heterosexually transmitted HIV infection.

Pocket protein complexes are recruited to distinct targets in quiescent and proliferating cells.

Biochemical and genetic studies have determined that retinoblastoma protein (pRB) tumor suppressor family members have overlapping functions. However, these studies have largely failed to distinguish functional differences between the highly related p107 and p130 proteins. Moreover, most studies pertaining to the pRB family and its principal target, the E2F transcription factor, have focused on cells that have reinitiated a cell cycle from quiescence, although recent studies suggest that cycling cells exhibit layers of regulation distinct from mitogenically stimulated cells. Using genome-wide chromatin immunoprecipitation, we show that there are distinct classes of genes directly regulated by unique combinations of E2F4, p107, and p130, including a group of genes specifically regulated in cycling cells. These groups exhibit both distinct histone acetylation signatures and patterns of mammalian Sin3B corepressor recruitment. Our findings suggest that cell cycle-dependent repression results from recruitment of an unexpected array of diverse complexes and reveals specific differences between transcriptional regulation in cycling and quiescent cells. In addition, factor location analyses have, for the first time, allowed the identification of novel and specific targets of the highly related transcriptional regulators p107 and p130, suggesting new and distinct regulatory networks engaged by each protein in continuously cycling cells.

The timing and extent of activation of diacylglycerol-responsive protein kinase-cs determines their ability to inhibit or promote platelet-derived growth factor-dependent DNA synthesis.

In response to natural agonists, such as platelet-derived growth factor (PDGF), diacylglycerol-responsive protein kinase Cs (PKCs) are activated at two distinct times, early and mid G1, and only the late activity is required for the transition into S phase. Surprisingly, the potent PKC activator phorbol 12-myristate 13-acetate (PMA) inhibits DNA synthesis when it is added in mid G1. Here we investigated why different PKC agonists had opposing effects on cell proliferation. We found that the magnitude and timing of PKC activation determined their ability to suppress DNA synthesis. Furthermore, potent activation of PKCs resulted in robust Erk activation and elevation of p21(CIP1). Finally, PMA was unable to block PDGF-dependent cell cycle progression in cells that lack p21(CIP1). These findings indicate that only potent activators of PKC were capable of blocking cell cycle progression, and the mechanism appears to involve an elevation of p21(CIP1).

A common set of gene regulatory networks links metabolism and growth inhibition.

Using genome-wide analysis of transcription factor occupancy, we investigated the mechanisms underlying three mammalian growth arrest pathways that require the pRB tumor suppressor family. We found that p130 and E2F4 cooperatively repress a common set of genes under each growth arrest condition and showed that growth arrest is achieved through repression of a core set of genes involved not only in cell cycle control but also mitochondrial biogenesis and metabolism. Motif-finding algorithms predicted the existence of nuclear respiratory factor-1 (NRF1) binding sites in E2F target promoters, and genome-wide factor binding analysis confirmed our predictions. We showed that NRF1, a factor known to regulate expression of genes involved in mitochondrial function, is a coregulator of a large number of E2F target genes. Our studies provide insights into E2F regulatory circuitry, suggest how factor occupancy can predict the expression signature of a given target gene, and reveal pathways deregulated in human tumors.

Wnt glycoproteins regulate the expression of FoxN1, the gene defective in nude mice.

T cell development and selection require the fully mature and diverse epithelial microenvironment of the thymus. Acquisition of these characteristics is dependent on expression of the forkhead (also known as winged-helix) transcription factor FoxN1, as a lack of functional FoxN1 results in aberrant epithelial morphogenesis and an inability to attract lymphoid precursors to the thymus primordium. However, the transcriptional control of Foxn1 expression has not been elucidated. Here we report that secreted Wnt glycoproteins, expressed by thymic epithelial cells and thymocytes, regulate epithelial Foxn1 expression in both autocrine and paracrine fashions. Wnt molecules therefore provide regulatory signals critical for thymic function.