A Comparative Analysis of the Interactions of the E6 Proteins from Cutaneous and Genital Papillomaviruses with p53 and E6AP in Correlation to Their Transforming Potential

AbstractA common necessity for all papillomaviruses is to induce DNA synthesis in quiescent cells. This is commonly achieved by the E7 gene product, which interferes with the function of members of the retinoblastoma family controlling transition from the G1-phase to the S-phase of the cell cycle. Uncontrolled entry into S-phase activates, however, negative growth control signals which have to be bypassed to achieve production of progeny viruses. In addition to inherent activities of the E7 protein, high risk genital types encode an E6 protein that overcomes p53-mediated G1-arrest and apoptosis in concert with the cellular factor E6AP by targeting p53 for the enhanced ubiquitin-dependent degradation. The key question, which of these functions of genital E6 and E7 proteins is responsible for the carcinogenic phenotype, is still not completely answered. In contrast to high risk genital types no immortalizing or transforming activities have been found for the E7 proteins of the high risk cutaneous HPV8 and 47. On the other hand the ability of the E6 protein to transform established rodent fibroblasts seems to be a property shared by high risk genital and cutaneous types. To examine the existence of a common E6-mediated transforming pathway for both virus groups we compared the properties of the cutaneous E6 proteins with already known functions of E6 proteins of genital viruses. For this we analyzed the E6 proteins of low risk and high risk cutaneous and genital papillomaviruses with respect to cell transformation, to their abilities to bind, degradate, and influence the activity of human p53, and to bind E6AP. The results of our study demonstrate a clear lack of interaction between the transforming E6 proteins of HPV1 and HPV8 and both cellular proteins p53 and E6AP. In contrast, we found E6AP-independent binding of HPV16 E6 and HPV6 E6 to p53, although both proteins were different in their transforming potential. Of all four proteins investigated, only HPV16 E6 was able to bind to p53 and E6AP and to induce degradation of the p53 protein in the reticulocyte system. When we investigated in frame deletion mutants of the E6 protein of HPV16 for their abilities to bind to p53 or E6AP, degradate, and inhibit the transactivation function of p53 and to transform rodent fibroblasts, no correlation between the different activities could be found. Mutants still able to bind p53 and E6AP lacked transforming ability and other mutants that were transformation-competent were deficient in p53 and E6AP binding

Solvation-guided design of fluorescent probes for discrimination of amyloids

The deposition of insoluble protein aggregates in the brain is a hallmark of many neurodegenerative diseases. While their exact role in neurodegeneration remains unclear, the presence of these amyloid deposits often precedes clinical symptoms. As a result, recent progress in imaging methods that utilize amyloid-specific small molecule probes have become a promising avenue for antemortem disease diagnosis. Here, we present a series of amino-aryl cyanoacrylate (AACA) fluorophores that show a turn-on fluorescence signal upon binding to amyloids in solution and in tissue. Using a theoretical model for environmental sensitivity of fluorescence together with ab initio computational modeling of the effects of polar environment on electron density distribution and conformational dynamics, we designed, synthesized, and evaluated a set of fluorophores that (1) bind to aggregated forms of Alzheimer's-related beta-amyloid peptides with low micromolar to high nanomolar affinities and (2) have the capability to fluorescently discriminate different amyloids based on differences in amino acid composition within the binding pocket through exploitation of their solvatochromic properties. These studies showcase the rational design of a family of amyloid-binding imaging agents that could be integrated with new optical approaches for the clinical diagnosis of amyloidoses, where accurate identification of the specific neurodegenerative disease could aid in the selection of a proper course for treatment

Giant Coulomb broadening and Raman lasing on ionic transitions

CW generation of anti-Stokes Raman laser on a number of blue-green argon-ion lines (4p-4s, 4p-3d) has been demonstrated with optical pumping from metastable levels 3d'^2G, 3d^4F. It is found, that the population transfer rate is increased by a factor of 3-5 (and hence, the output power of such Raman laser) owing to Coulomb diffusion in the velocity space. Measured are the excitation and relaxation rates for the metastable level. The Bennett hole on the metastable level has been recorded using the probe field technique. It has been shown that the Coulomb diffusion changes shape of the contour to exponential cusp profile while its width becomes 100 times the Lorentzian one and reaches values close to the Doppler width. Such a giant broadening is also confirmed by the shape of the absorption saturation curve.Comment: RevTex 18 pages, 5 figure

An intervention to improve care and reduce costs for high-risk patients with frequent hospital admissions: a pilot study

<p>Abstract</p> <p>Background</p> <p>A small percentage of high-risk patients accounts for a large proportion of Medicaid spending in the United States, which has become an urgent policy issue. Our objective was to pilot a novel patient-centered intervention for high-risk patients with frequent hospital admissions to determine its potential to improve care and reduce costs.</p> <p>Methods</p> <p>Community and hospital-based care management and coordination intervention with pre-post analysis of health care utilization. We enrolled Medicaid fee-for-service patients aged 18-64 who were admitted to an urban public hospital and identified as being at high risk for hospital readmission by a validated predictive algorithm. Enrolled patients were evaluated using qualitative and quantitative interview techniques to identify needs such as transportation to/advocacy during medical appointments, mental health/substance use treatment, and home visits. A community housing partner initiated housing applications in-hospital for homeless patients. Care managers facilitated appropriate discharge plans then worked closely with patients in the community using a harm reduction approach.</p> <p>Results</p> <p>Nineteen patients were enrolled; all were male, 18/19 were substance users, and 17/19 were homeless. Patients had a total of 64 inpatient admissions in the 12 months before the intervention, versus 40 in the following 12 months, a 37.5% reduction. Most patients (73.3%) had fewer inpatient admissions in the year after the intervention compared to the prior year. Overall ED visits also decreased after study enrollment, while outpatient clinic visits increased. Yearly study hospital Medicaid reimbursements fell an average of $16,383 per patient.</p> <p>Conclusions</p> <p>A pilot intervention for high-cost patients shows promising results for health services usage. We are currently expanding our model to serve more patients at additional hospitals to see if the pilot's success can be replicated.</p> <p>Trial registration</p> <p>Clinicaltrials.gov Identifier: <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1292096">NCT01292096</a></p

Repair of UV-induced thymine dimers is compromised in cells expressing the E6 protein from human papillomaviruses types 5 and 18

Ultraviolet (UV) irradiation is a major mutagenic environmental agent, causing the appearance of DNA adducts that, if unrepaired, may give rise to mutations. Ultraviolet radiation has been indicated as a major risk factor in the development of nonmelanoma skin cancers; however, recent reports have suggested that infections with human papillomaviruses, a widespread family of epitheliotropic DNA viruses, may also contribute to the tumorigeneic process. Here, we investigated whether expression of the E6 protein from different HPV types interfere with the repair of thymine dimers caused by UV-B radiation. Results show that unrepaired DNA damage can be observed in UV-B-irradiated cells expressing the E6 protein of HPV types found in cervical and epithelial cancers. Moreover, such cells have the ability to overcome the G(1) cell cycle checkpoint induced as a result of unrepaired DNA. (C) 2004 Cancer Research UK

Active Mg Estimation Using Thermal Analysis: A Rapid Method to Control Nodularity in Ductile Cast Iron Production

Appropriate nodularity in ductile iron castings is strongly associated with the presence of high enough not combined Mg dissolved in the melt to cast. However, the residual Mg which is commonly measured for production control accounts for both dissolved Mg and Mg combined as oxides and sulfides. To account for the uncertainties associated with such a control, it is quite usual to over treat the melt with the risk of porosity appearance. A new methodology based on thermal analysis has been developed in the present work so as to estimate the amount of free Mg dissolved in the melt ready for pouring. A combination of Te mixture and a new “reactive mixture” composed of sulfur plus a commercial inoculant has been prepared for this purpose. This reactive mixture is able to transform the magnesium remaining dissolved in the melt to combined forms of this element. Experiments performed both during start of production (when Mg overtreatment is usual) and during normal mass production indicate that important variations of free Mg occur without relevant changes in residual Mg content as determined by spectrometry. The method developed in the present work has shown to be highly effective to detect those melt batches where active Mg content is not high enough for guaranteeing a correct nodularity of castings. Selection of proper active Mg thresholds and a correct inoculation process are critical to avoid “false”-negative results when using this new method

Deceleration during 'real life' motor vehicle collisions – a sensitive predictor for the risk of sustaining a cervical spine injury?

<p>Abstract</p> <p>Background</p> <p>The predictive value of trauma impact for the severity of whiplash injuries has mainly been investigated in sled- and crash-test studies. However, very little data exist for real-life accidents. Therefore, the predictive value of the trauma impact as assessed by the change in velocity of the car due to the collision (ΔV) for the resulting cervical spine injuries were investigated in 57 cases after real-life car accidents.</p> <p>Methods</p> <p>ΔV was determined for every car and clinical findings related to the cervical spine were assessed and classified according to the Quebec Task Force (QTF).</p> <p>Results</p> <p>In our study, 32 (56%) subjects did not complain about symptoms and were therefore classified as QTF grade 0; 25 (44%) patients complained of neck pain: 8 (14%) were classified as QTF grade I, 6 (10%) as QTF grade II, and 11 (19%) as QTF grade IV. Only a slight correlation (r = 0.55) was found between the reported pain and ΔV. No relevant correlation was found between ΔV and the neck disability index (r = 0.46) and between ΔV and the QTF grade (r = 0.45) for any of the collision types. There was no ΔV threshold associated with acceptable sensitivity and specificity for the prognosis of a cervical spine injury.</p> <p>Conclusion</p> <p>The results of this study indicate that ΔV is not a conclusive predictor for cervical spine injury in real-life motor vehicle accidents. This is of importance for surgeons involved in medicolegal expertise jobs as well as patients who suffer from whiplash-associated disorders (WADs) after motor vehicle accidents.</p> <p>Trial registration</p> <p>The study complied with applicable German law and with the principles of the Helsinki Declaration and was approved by the institutional ethics commission.</p

The publics' understanding of daily caloric recommendations and their perceptions of calorie posting in chain restaurants

<p>Abstract</p> <p>Background</p> <p>Calorie posting in chain restaurants has received increasing attention as a policy lever to reduce energy intake. Little research has assessed consumer understanding of overall daily energy requirements or perceived effectiveness of calorie posting.</p> <p>Methods</p> <p>A phone survey was conducted from May 1 through 17, 2009 with 663 randomly selected, nationally-representative adults aged 18 and older, including an oversample of Blacks and Hispanics in the United States. To examine differences in responses by race and ethnicity (White, Black, and Hispanic) and gender, we compared responses by conducting chi-squared tests for differences in proportions.</p> <p>Results</p> <p>We found that most Americans were knowledgeable about energy requirements for moderately active men (78%) and women (69%), but underestimated energy requirements for inactive adults (60%). Whites had significantly higher caloric literacy and confidence about their caloric knowledge than Blacks and Hispanics (p < 0.05). As compared to their counterparts, Blacks, Hispanics and women reported a significantly higher likelihood of eating at a chain restaurant and of selecting lower calorie foods where caloric information was posted. Most Americans favored the government requiring chain restaurants to post calorie information on menus at the point of purchase (68%). Support for government mandated calorie posting in chain restaurants was significantly higher among Blacks, Hispanics and women as compared to their counterparts. The public was divided about the mode of caloric information that would best help them make a lower calorie decision; a third favored number of calories (35%) which is the current standard mode of presenting caloric information in chain restaurants, a third favored a physical activity equivalent (26%), and a third favored percentage of total energy intake (39%).</p> <p>Conclusion</p> <p>Mandating calorie posting in chain restaurants may be a useful policy tool for promoting energy balance, particularly among Blacks, Hispanics and women who have higher obesity risk.</p

Gene expression profile of cervical and skin tissues from human papillomavirus type 16 E6 transgenic mice

<p>Abstract</p> <p>Background</p> <p>Although K14E6 transgenic mice develop spontaneous tumors of the skin epithelium, no spontaneous reproductive tract malignancies arise, unless the transgenic mice were treated chronically with 17β-estradiol. These findings suggest that E6 performs critical functions in normal adult cervix and skin, highlighting the need to define E6-controlled transcriptional programs in these tissues.</p> <p>Methods</p> <p>We evaluated the expression profile of 14,000 genes in skin or cervix from young K14E6 transgenic mice compared with nontransgenic. To identify differentially expressed genes a linear model was implemented using R and the LIMMA package. Two criteria were used to select the set of relevant genes. First a set of genes with a Log-odds ≥ 3 were selected. Then, a hierarchical search of genes was based on Log Fold Changes.</p> <p>Results</p> <p>Microarray analysis identified a total of 676 and 1154 genes that were significantly up and down-regulated, respectively, in skin from K14E6 transgenic mice. On the other hand, in the cervix from K14E6 transgenic mice we found that only 97 and 252 genes were significantly up and down-regulated, respectively. One of the most affected processes in the skin from K14E6 transgenic mice was the cell cycle. We also found that skin from transgenic mice showed down-regulation of pro-apoptotic genes and genes related to the immune response. In the cervix of K14E6 transgenic mice, we could not find affected any gene related to the cell cycle and apoptosis pathways but did observe alterations in the expression of immune response genes. Pathways such as angiogenesis, cell junction and epidermis development, also were altered in their gene expression profiles in both tissues.</p> <p>Conclusion</p> <p>Expression of the HPV16 E6 oncoprotein in our model alters expression of genes that fell into several functional groups providing insights into pathways by which E6 deregulate cell cycle progression, apoptosis, the host resistance to infection and immune function, providing new opportunities for early diagnostic markers and therapeutic drug targets.</p